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Sample records for extra terrestrial bodies

  1. Extra Terrestrial Lava Flows

    NASA Technical Reports Server (NTRS)

    Lopes-Gautier, R.

    1993-01-01

    Volcanism has been one of the major processes shaping the surfaces of the terrestrial planets. Lava flows have been identified on the Moon, Mars, Venus, and on Juptier's moon Io. The study of extra-terrestrial lavas has largely relied on the interpretation of remotely acquired imaging, topographic and spectroscopic data. Models relating the final flow morpohology to eruption characteristics and magma chemistry have been important tools in the interpretation of these data.

  2. The search for extra-terrestrial intelligence.

    PubMed

    Drake, Frank

    2011-02-13

    Modern history of the search for extra-terrestrial intelligence is reviewed. The history of radio searches is discussed, as well as the major advances that have occurred in radio searches and prospects for new instruments and search strategies. Recent recognition that searches for optical and infrared signals make sense, and the reasons for this are described, as well as the equipment and special detection methods used in optical searches. The long-range future of the search for extra-terrestrial intelligence (SETI) is discussed in the context of the history of rapid change, on the cosmic and even the human time scale, of the paradigms guiding SETI searches. This suggests that SETI searches be conducted with a very open mind. PMID:21220287

  3. Radio communications with extra-terrestrial civilizations

    NASA Technical Reports Server (NTRS)

    Kotelnikov, V. A.

    1974-01-01

    Communications between civilizations within our galaxy at the present level of radio engineering is possible, although civilizations must begin to search for each other to achieve this. If an extra-terrestrial civilization possessing a technology at our level wishes to make itself known and will transmit special radio signals to do this, then it can be picked up by us at a distance of several hundreds of light years using already existing radio telescopes and specially built radio receivers. If it wishes, this civilization can also send us information without awaiting our answer.

  4. Quarantine provisions for unmanned extra-terrestrial missions

    NASA Technical Reports Server (NTRS)

    1976-01-01

    This document sets forth requirements applicable to unmanned planetary flight programs which are necessary to enable the Associate Administrator for Space Science to fulfill those responsibilities pertaining to planetary quarantine as stated in NPD 8020.7 and NPD 8020.10A. This document is specifically directed to the control of terrestrial microbial contamination associated with unmanned space vehicles intended to encounter, orbit, flyby, or otherwise be in the vicinity of extra-terrestrial solar system bodies. The requirements of this document apply to all unmanned planetary flight programs. This includes solar system exploratory missions to the major planets as well as missions to planet satellites, or to other solar system objects that may be of scientific interest. This document is not applicable to terrestrial (including lunar) missions and manned missions. NASA officials having cognizance of applicable flight programs will invoke these requirements in such directives or contractual instruments as may be necessary to assure their implementation.

  5. Migration & Extra-solar Terrestrial Planets: Watering the Planets

    NASA Astrophysics Data System (ADS)

    Carter-Bond, Jade C.; O'Brien, David P.; Raymond, Sean N.

    2014-04-01

    A diverse range of terrestrial planet compositions is believed to exist within known extrasolar planetary systems, ranging from those that are relatively Earth-like to those that are highly unusual, dominated by species such as refractory elements (Al and Ca) or C (as pure C, TiC and SiC)(Bond et al. 2010b). However, all prior simulations have ignored the impact that giant planet migration during planetary accretion may have on the final terrestrial planetary composition. Here, we combined chemical equilibrium models of the disk around five known planetary host stars (Solar, HD4203, HD19994, HD213240 and Gl777) with dynamical models of terrestrial planet formation incorporating various degrees of giant planet migration. Giant planet migration is found to drastically impact terrestrial planet composition by 1) increasing the amount of Mg-silicate species present in the final body; and 2) dramatically increasing the efficiency and amount of water delivered to the terrestrial bodies during their formation process.

  6. A Review of Extra-Terrestrial Mining Concepts

    NASA Technical Reports Server (NTRS)

    Mueller, R. P.; van Susante, P. J.

    2012-01-01

    Outer space contains a vast amount of resources that offer virtually unlimited wealth to the humans that can access and use them for commercial purposes. One of the key technologies for harvesting these resources is robotic mining of regolith, minerals, ices and metals. The harsh environment and vast distances create challenges that are handled best by robotic machines working in collaboration with human explorers. Humans will benefit from the resources that will be mined by robots. They will visit outposts and mining camps as required for exploration, commerce and scientific research, but a continuous presence is most likely to be provided by robotic mining machines that are remotely controlled by humans. There have been a variety of extra-terrestrial robotic mining concepts proposed over the last 40 years and this paper will attempt to summarize and review concepts in the public domain (government, industry and academia) to serve as an informational resource for future mining robot developers and operators. The challenges associated with these concepts will be discussed and feasibility will be assessed. Future needs associated with commercial efforts will also be investigated.

  7. A Review of Extra-Terrestrial Mining Robot Concepts

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Van Susante, Paul J.

    2011-01-01

    Outer space contains a vast amount of resources that offer virtually unlimited wealth to the humans that can access and use them for commercial purposes. One of the key technologies for harvesting these resources is robotic mining of regolith, minerals, ices and metals. The harsh environment and vast distances create challenges that are handled best by robotic machines working in collaboration with human explorers. Humans will benefit from the resources that will be mined by robots. They will visit outposts and mining camps as required for exploration, commerce and scientific research, but a continuous presence is most likely to be provided by robotic mining machines that are remotely controlled by humans. There have been a variety of extra-terrestrial robotic mining concepts proposed over the last 100 years and this paper will attempt to summarize and review concepts in the public domain (government, industry and academia) to serve as an informational resource for future mining robot developers and operators. The challenges associated with these concepts will be discussed and feasibility will be assessed. Future needs associated with commercial efforts will also be investigated.

  8. Applying Biomimetic Algorithms for Extra-Terrestrial Habitat Generation

    NASA Technical Reports Server (NTRS)

    Birge, Brian

    2012-01-01

    The objective is to simulate and optimize distributed cooperation among a network of robots tasked with cooperative excavation on an extra-terrestrial surface. Additionally to examine the concept of directed Emergence among a group of limited artificially intelligent agents. Emergence is the concept of achieving complex results from very simple rules or interactions. For example, in a termite mound each individual termite does not carry a blueprint of how to make their home in a global sense, but their interactions based strictly on local desires create a complex superstructure. Leveraging this Emergence concept applied to a simulation of cooperative agents (robots) will allow an examination of the success of non-directed group strategy achieving specific results. Specifically the simulation will be a testbed to evaluate population based robotic exploration and cooperative strategies while leveraging the evolutionary teamwork approach in the face of uncertainty about the environment and partial loss of sensors. Checking against a cost function and 'social' constraints will optimize cooperation when excavating a simulated tunnel. Agents will act locally with non-local results. The rules by which the simulated robots interact will be optimized to the simplest possible for the desired result, leveraging Emergence. Sensor malfunction and line of sight issues will be incorporated into the simulation. This approach falls under Swarm Robotics, a subset of robot control concerned with finding ways to control large groups of robots. Swarm Robotics often contains biologically inspired approaches, research comes from social insect observation but also data from among groups of herding, schooling, and flocking animals. Biomimetic algorithms applied to manned space exploration is the method under consideration for further study.

  9. Towards polarimetry as a tool for the detection of extra-terrestrial life

    NASA Astrophysics Data System (ADS)

    Bagnulo, Stefano; Sterzik, Michael F.; Cellino, Alberto

    2015-10-01

    Linear broadband polarimetry is used to characterize the objects of our solar system, and has also been proposed as a diagnostic tool for the atmospheres of exo-solar planets. Homochirality characterizes life as we know it and induces circular polarization in the diffuse reflectance spectra of biotic material. Hence it has been suggested that circular polarimetry may be used as a remote sensing tool for the search of extra-terrestrial life. With this motivation in mind we have decided to explore the potential of both linear and circular spectropolarimetry as a diagnostic tool for remote sensing of biotic material. We have used the calibration unit of the EFOSC2 instrument of the La Silla Observatory to obtain low resolution, but high signal to noise circular and linear spectropolarimetric measurements of a number of inorganic and organic materials. We then compare our "laboratory data" with spectropolarimetric observations of atmosphere-less bodies of our solar system and of Earthshine obtained with instruments very similar to that one used for our laboratory samples. We conclude that linear polarization measurements are more suitable than circular polarization measurements for the characterization of planetary surfaces and atmospheres, and for the search of extra-terrestrial life.

  10. Reducing Extra-Terrestrial Excavation Forces with Percussion

    NASA Technical Reports Server (NTRS)

    Schuler, Jason; Mueller, Robert; Smith, Drew; Nick, Andrew; Lippitt, Thomas

    2012-01-01

    High launch costs and mission requirements drive the need for low mass excavators with mobility platforms, which in turn have little traction and excavation reaction capacity in low gravity environments. This presents the need for precursor and long term future missions with low mass robotic mining technology to perform In-Situ Resource Utilization (ISRU) tasks. This paper discusses a series of experiments that investigate the effectiveness of a percussive digging device to reduce excavation loads and thereby the mass of the excavator itself. The goal of percussive excavation is to fluidize dry regolith in front of the leading edge of the tool by mechanically separating the microscopic interlocking grains resulting in a reduced force needed to shear the soil. There are several variables involved with this technique; this experiment varied: Impact energy, frequency, and excavation speed and held constant: impact direction, depth of cut, angle of tool, and soil bulk density. The test apparatus consisted of an aluminum truss bridge with a central pivoting arm. Attached to the arm was a winch with a load cell in line that recorded the tension in the cable and therefore the excavation load. The arm could be adjusted for excavation depth which was recorded along with the arm angle relative to the bridge. A percussive mechanism and 30" wide pivoting bucket were attached at the end of the arm simulating a basic backhoe with a percussion direction tangent to the direction of . movement. Internally the mechanism used a set of die springs and barrel cam to produce the percussive blow. By changing the springs and the speed of the motor the impact energy and frequency of percussion could be varied independently. Impact energies from 11.2J to 30.5J and frequencies from 0 BPM to 700 BPM were investigated. A reduction in excavation force of as much as 51% was achieved in this experimental investigation. Smaller percussive digging implements, tested by others, have achieved a reduction of as much as 72%. This paper will examine the effects of impact energy, frequency, scaling and their effect on excavation forces in a dry granular material such as lunar regolith. The past several years have shown an increasing interest in mining space resources both for exploration and commercial enterprises. This work studied the benefits and risks of percussive excavation and preliminry results indicate that this technique may become an enabling technology for extra-terrestrial excavation of regolith and ice.

  11. Possible Existence of Extra-Terrestrial Technology in the Solar System

    NASA Astrophysics Data System (ADS)

    Burke-Ward, R.

    Potential features of the design and function of extra-terrestrial probes are discussed with the aim of establishing criteria for search, detection and contact. Probes are categorised according to three primary areas of function - data-gathering, direct action, and sentient entities. Conclusions are drawn about possible probe technologies and modes of behaviour.

  12. The implications of the discovery of extra-terrestrial life for religion.

    PubMed

    Peters, Ted

    2011-02-13

    This paper asks about the future of religion: (i) Will confirmation of extra-terrestrial intelligence (ETI) cause terrestrial religion to collapse? 'No' is the answer based upon a summary of the 'Peters ETI Religious Crisis Survey'. Then the paper examines four specific challenges to traditional doctrinal belief likely to be raised at the detection of ETI: (ii) What is the scope of God's creation? (iii) What can we expect regarding the moral character of ETI? (iv) Is one earthly incarnation in Jesus Christ enough for the entire cosmos, or should we expect multiple incarnations on multiple planets? (v) Will contact with more advanced ETI diminish human dignity? More than probable contact with extra-terrestrial intelligence will expand the Bible's vision so that all of creation--including the 13.7 billion year history of the universe replete with all of God's creatures--will be seen as the gift of a loving and gracious God. PMID:21220288

  13. Discovery of extra-terrestrial life: assessment by scales of its importance and associated risks.

    PubMed

    Almr, Ivn; Race, Margaret S

    2011-02-13

    The Rio Scale accepted by the SETI Committee of the International Academy of Astronautics in 2002 is intended for use in evaluating the impact on society of any announcement regarding the discovery of evidence of extra-terrestrial (ET) intelligence. The Rio Scale is mathematically defined using three parameters (class of phenomenon, type of discovery and distance) and a ? factor, the assumed credibility of a claim. This paper proposes a new scale applicable to announcements alleging evidence of ET life within or outside our Solar System. The London Scale for astrobiology has mathematical structure and logic similar to the Rio Scale, and uses four parameters (life form, nature of phenomenon, type of discovery and distance) as well as a credibility factor ? to calculate a London Scale index (LSI) with values ranging from 0 to 10. The level of risk or biohazard associated with a purported discovery is evaluated independently of the LSI value and may be ranked in four categories. The combined information is intended to provide a scalar assessment of the scientific importance, validity and potential risks associated with putative evidence of ET life discovered on Earth, on nearby bodies in the Solar System or in our Galaxy. PMID:21220291

  14. The search for extra-terrestrial intelligence: current status and future prospects

    NASA Astrophysics Data System (ADS)

    Bowyer, Stuart

    2015-09-01

    The idea that credible searches for Extra-Terrestrial Intelligence (ETI) could be carried out were laid out in detail in a classic paper by Morrison and Cocconi (1959).1 They suggested using the radio band for these searches. Since then radio searches have been carried out by over sixty different groups. No signals from ETIs have been identified. In this paper I will discuss the argument for the existence of extra-terrestrial intelligence. I will provide a method to estimate the number of extragalactic civilizations that are capable of signaling us and consider the uncertainties inherent in this estimate. I will provide the rationale for searching for these signals in the radio band. Finally I will discuss the future prospects for this endeavor.

  15. The weak force and SETH: The search for Extra-Terrestrial Homochirality

    SciTech Connect

    MacDermott, A.J.

    1996-07-01

    We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality{emdash}SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the {ital Z}{sup 0} boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that further crystal counts should be carried out to establish whether reported excesses of L quartz are real. Finding extra-terrestrial molecules of the same hand as on Earth would lend support to the universal chiral influence of the weak force. We describe a novel miniaturized space polarimeter, called the SETH Cigar, which we hope to use to detect optical rotation on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. Even if we do not find the same hand as on Earth, finding extra-terrestrial optical rotation would be of enormous importance as it would still be the homochiral signature of life. {copyright} {ital 1996 American Institute of Physics.}

  16. The weak force and SETH: The search for Extra-Terrestrial Homochirality

    NASA Astrophysics Data System (ADS)

    MacDermott, Alexandra J.

    1996-07-01

    We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality-SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the Z0 boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that further crystal counts should be carried out to establish whether reported excesses of L quartz are real. Finding extra-terrestrial molecules of the same hand as on Earth would lend support to the universal chiral influence of the weak force. We describe a novel miniaturized space polarimeter, called the SETH Cigar, which we hope to use to detect optical rotation on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. Even if we do not find the same hand as on Earth, finding extra-terrestrial optical rotation would be of enormous importance as it would still be the homochiral signature of life.

  17. Fear, pandemonium, equanimity and delight: human responses to extra-terrestrial life.

    PubMed

    Harrison, Albert A

    2011-02-13

    How will people respond to the discovery of extra-terrestrial life? Potentially useful resources for addressing this question include historical prototypes, disaster studies and survey research. Reactions will depend on the interplay of the characteristics of the newly found life, the unfolding of the discovery, the context and content of the message and human information processing as shaped by biology, culture and psychology. Pre-existing images of extra-terrestrials as god-like, demonic, or artificial will influence first impressions that may prove highly resistant to change. Most probably people will develop comprehensive images based on minimal information and assess extra-terrestrials in the same ways that they assess one another. Although it is easy to develop frightening scenarios, finding microbial life in our Solar System or intercepting a microwave transmission from many light years away are less likely to be met with adverse reactions such as fear and pandemonium than with positive reactions such as equanimity and delight. PMID:21220289

  18. Predicting what extra-terrestrials will be like: and preparing for the worst.

    PubMed

    Morris, Simon Conway

    2011-02-13

    It is difficult to imagine evolution in alien biospheres operating in any manner other than Darwinian. Yet, it is also widely assumed that alien life-forms will be just that: strange, un-nerving and probably repulsive. There are two reasons for this view. First, it is assumed that the range of habitable environments available to extra-terrestrial life is far wider than on Earth. I suggest, however, that terrestrial life is close to the physical and chemical limits of life anywhere. Second, it is a neo-Darwinian orthodoxy that evolution lacks predictability; imagining what extra-terrestrial life would look like in any detail is a futile exercise. To the contrary, I suggest that the outcomes of evolution are remarkably predictable. This, however, leads us to consider two opposites, both of which should make our blood run cold. The first, and actually extremely unlikely, is that alien biospheres will be strikingly similar to our terrestrial equivalent and that in such biospheres intelligence will inevitably emerge. The reasons for this revolve around the ubiquity of evolutionary convergence, the determinate structure of the Tree of Life and molecular inherency. But if something like a human is an inevitability, why do I also claim that the first possibility is 'extremely unlikely'? Simply because the other possibility is actually the correct answer. Paradoxically, we and our biosphere are completely alone. So which is worse? Meeting ourselves or meeting nobody? PMID:21220280

  19. Montana Evidence for Extra-Terrestrial Impact Event That Caused Ice-Age Mammal Die- Off

    NASA Astrophysics Data System (ADS)

    Baker, D. W.; Miranda, P. J.; Gibbs, K. E.

    2008-05-01

    Evidence has been found in Montana for an extra-terrestrial impact event previously documented in the States of AZ, NM, NC, and SC and in Alberta and Manitoba. A mammoth fossil site dated at 11.5 ka (C14) before present (BP) was described in 1969 as the last mammoth occurrence in Montana. The mammoth remains were found in an organic-rich layer--a black mat. The black mat contains abundant charcoal (evidence for forest fire), black carbon glass foam, plant material deposited in a pond, and unrusted iron micro-meteorites. SEM photos of iron micro-meteorites reveal fusion crusts, flow lines, and micro-impact craters--direct evidence for an extra- terrestrial origin. One 140 ?m long micro-meteorite is 96 wt.% Fe and 4% Mn. Another is 71% Fe and 29% Ti. Mammoth tusks contain rusty pits, consistent with iron micro-meteorites that were embedded and then rusted out. A sample of carbon glass in the black mat contains 62% C, 22% O, 6% Fe, 4% Ca, 4% Si, and 2% Al. At the Indian Creek Archeological Site near Townsend, MT below the cultural layers and below a 11.2 ka (C14) volcanic ash layer there are individual glass bubbles about 1 mm in diameter with micro-impact craters. The size distribution of these micro-craters resembles the size distribution of lunar craters, but at a vastly different scale. The glass contains 53% C, 33% O, 6% Ca, 4% Si, 2% Al, 1% Mg, and 0.6% K. The carbon glass and micro-meteorites suggest a comet rather a meteorite origin for the extra-terrestrial material.

  20. The detection of extra-terrestrial life and the consequences for science and society.

    PubMed

    Dominik, Martin; Zarnecki, John C

    2011-02-13

    Astronomers are now able to detect planets orbiting stars other than the Sun where life may exist, and living generations could see the signatures of extra-terrestrial life being detected. Should it turn out that we are not alone in the Universe, it will fundamentally affect how humanity understands itself--and we need to be prepared for the consequences. A Discussion Meeting held at the Royal Society in London, 6-9 Carlton House Terrace, on 25-26 January 2010, addressed not only the scientific but also the societal agenda, with presentations covering a large diversity of topics. PMID:21220276

  1. Chemical methods for searching for evidence of extra-terrestrial life.

    PubMed

    Pillinger, Colin

    2011-02-13

    This paper describes the chemical concepts used for the purpose of detecting life in extra-terrestrial situations. These methods, developed initially within the oil industry, have been used to determine when life began on Earth and for investigating the Moon and Mars via space missions. In the case of Mars, the Viking missions led to the realization that we had meteorites from Mars on Earth. The study of Martian meteorites in the laboratory provides tantalizing clues for life on Mars in both the ancient and recent past. Meteorite analyses led to the launch of the Beagle 2 spacecraft, which was designed to prove that life-detection results obtained on Earth were authentic and not confused by terrestrial contamination. Some suggestions are made for future work. PMID:21220284

  2. Topographic-driven instabilities in terrestrial bodies

    NASA Astrophysics Data System (ADS)

    Vantieghem, S.; Cebron, D.; Herreman, W.; Lacaze, L.

    2013-12-01

    Models of internal planetary fluid layers (core flows, subsurface oceans) commonly assume that these fluid envelopes have a spherical shape. This approximation however entails a serious restriction from the fluid dynamics point of view. Indeed, in the presence of mechanical forcings (precession, libration, nutation or tides) due to gravitational interaction with orbiting partners, boundary topography (e.g. of the core-mantle boundary) may excite flow instabilities and space-filling turbulence. These phenomena may affect heat transport and dissipation at the main order. Here, we focus on instabilities driven by longitudinal libration. Using a suite of theoretical tools and numerical simulations, we are able to discern a parameter range for which instability may be excited. We thereby consider deformations of different azimuthal order. This study gives the first numerical evidence of the tripolar instability. Furthermore, we explore the non-linear regime and investigate the amplitude as well as the dissipation of the saturated instability. Indeed, these two quantities control the torques on the solid layers and the thermal transport. Furthermore, based on this results, we address the issue of magnetic field generation associated with these flows (by induction or by dynamo process). This instability mechanism applies to both synchronized as non-synchronized bodies. As such, our results show that a tripolar instability might be present in various terrestrial bodies (Early Moon, Gallilean moons, asteroids, etc.), where it could participate in dynamo action. Simulation of a libration-driven tripolar instability in a deformed spherical fluid layer: snapshot of the velocity magnitude, where a complex 3D flow pattern is established.

  3. The use of extra-terrestrial oceans to test ocean acoustics students.

    PubMed

    Leighton, T G

    2012-03-01

    The existence of extra-terrestrial oceans offers the opportunities to set examination questions for which students in underwater acoustics do not already know the answers. The limited set of scenarios in Earth's oceans that can be presented to students as tractable examination questions means that, rather than properly assessing the individual scenario, students can rely on knowledge from previous examples in assessing, for example, which terms in equations are large and small, and what numerical values the answers are likely to take. The habit of adapting previous solutions with which the student is comfortable, to new scenarios, is not a safe approach to learn, as it ill equips the future scientist or engineer to identify and tackle problems which contain serious departures from their experience. PMID:22423807

  4. ORIGINS OF NON-MASS-DEPENDENT FRACTIONATION OF EXTRA-TERRESTRIAL OXYGEN

    SciTech Connect

    Barcena, Homar; Connolly, Harold C.

    2012-08-01

    The distribution of oxygen isotopes in meteorites and within the earliest solids that formed in the solar system hints that the precursors of these materials must have undergone a mass-independent process. The mass-independent process is specifically one that fractionates {sup 16}O from {sup 17}O and {sup 18}O. This chemical signature is indicative of non-equilibrium processing, which bear resemblance to some unusual terrestrial phenomenon such as fractionation of ozone in the upper Earth atmosphere. That the mass-independent fractionation of oxygen isotopes is preserved within petrological records presents planetary scientists interesting clues to the events that may have occurred during the formation of the solar system. Currently, there are several hypotheses on the origins of the oxygen isotope distribution within primitive planetary materials, which include both thermal and photochemical models. We present a new model based on a physico-chemical hypothesis for the origin of non-mass-dependent O-isotope distribution in oxygen-bearing extra-terrestrial materials, which originated from the disproportionation of CO in dark molecular clouds to create CO{sub 2} reservoirs. The disproportionation created a reservoir of heavy oxygen isotopes and could have occurred throughout the evolution of the disk. The CO{sub 2} was a carrier of the isotope anomaly in the solar nebula and we propose that non-steady-state mixing of these reservoirs with the early rock-forming materials during their formation corresponds with the birth and evolution of the solar system.

  5. The forthcoming EISCAT_3D as an extra-terrestrial matter monitor

    NASA Astrophysics Data System (ADS)

    Pellinen-Wannberg, Asta; Kero, Johan; Häggström, Ingemar; Mann, Ingrid; Tjulin, Anders

    2016-04-01

    It is important to monitor the extra-terrestrial dust flux in the Earth's environment and into the atmosphere. Meteoroids threaten the infrastructure in space as hypervelocity hits by micron-sized granules continuously degrade the solar panels and other satellite surfaces. Through their orbital elements meteoroids can be associated to the interplanetary dust cloud, comets, asteroids or the interstellar space. The ablation products of meteoroids participate in many physical and chemical processes at different layers in the atmosphere, many of them occurring in the polar regions. High-power large-aperture (HPLA) radars, such as the tristatic EISCAT UHF together with the EISCAT VHF, have been versatile instruments for studying many properties of the meteoroid population, even though they were not initially designed for this purpose. The future EISCAT_3D will comprise a phased-array transmitter and several phased-array receivers distributed in northern Scandinavia. These will work at 233 MHz centre frequency with power up to 10 MW and run advanced signal processing systems. The facility will in many aspects be superior to its predecessors as the first radar to combine volumetric-, aperture synthesis- and multistatic imaging as well as adaptive experiments. The technical design goals of the radar respond to the scientific requests from the user community. The VHF frequency and the volumetric imaging capacity will increase the collecting volume compared to the earlier UHF, the high transmitter power will increase the sensitivity of the radar, and the interferometry will improve the spatial resolution of the orbit estimates. The facility will be able to observe and define orbits to about 10% of the meteors from the established mass flux distribution that are large or fast enough to produce an ionization mantle around the impacting meteoroid within the collecting volume. The estimated annual mean of about 190 000 orbits per day with EISCAT_3D gives many orders of magnitude higher detected orbit rates than the earlier tristatic UHF radar.

  6. The game of active search for extra-terrestrial intelligence: breaking the `Great Silence'

    NASA Astrophysics Data System (ADS)

    de Vladar, Harold P.

    2013-01-01

    The search for extra-terrestrial intelligence (SETI) has been performed principally as a one-way survey, listening of radio frequencies across the Milky Way and other galaxies. However, scientists have engaged in an active messaging only rarely. This suggests the simple rationale that if other civilizations exist and take a similar approach to ours, namely listening but not broadcasting, the result is a silent universe. A simple game theoretical model, the prisoner's dilemma, explains this situation: each player (civilization) can passively search (defect), or actively search and broadcast (cooperate). In order to maximize the payoff (or, equivalently, minimize the risks) the best strategy is not to broadcast. In fact, the active search has been opposed on the basis that it might be dangerous to expose ourselves. However, most of these ideas have not been based on objective arguments, and ignore accounting of the possible gains and losses. Thus, the question stands: should we perform an active search? I develop a game-theoretical framework where civilizations can be of different types, and explicitly apply it to a situation where societies are either interested in establishing a two-way communication or belligerent and in urge to exploit ours. The framework gives a quantitative solution (a mixed-strategy), which is how frequent we should perform the active SETI. This frequency is roughly proportional to the inverse of the risk, and can be extremely small. However, given the immense amount of stars being scanned, it supports active SETI. The model is compared with simulations, and the possible actions are evaluated through the San Marino scale, measuring the risks of messaging.

  7. Molecular Physiology of an Extra-renal Cl(-) Uptake Mechanism for Body Fluid Cl(-) Homeostasis.

    PubMed

    Wang, Yi-Fang; Yan, Jia-Jiun; Tseng, Yung-Che; Chen, Ruo-Dong; Hwang, Pung-Pung

    2015-01-01

    The development of an ion regulatory mechanism for body fluid homeostasis was an important trait for vertebrates during the evolution from aquatic to terrestrial life. The homeostatic mechanism of Cl(-) in aquatic fish appears to be similar to that of terrestrial vertebrates; however, the mechanism in non-mammalian vertebrates is poorly understood. Unlike in mammals, in which the kidney plays a central role, in most fish species, the gill is responsible for the maintenance of Cl(-) homeostasis via Cl(-) transport uptake mechanisms. Previous studies in zebrafish identified Na(+)-Cl(-) cotransporter (NCC) 2b-expressing cells in the gills and skin as the major ionocytes responsible for Cl(-) uptake, similar to distal convoluted tubular cells in mammalian kidney. However, the mechanism by which basolateral ions exit from NCC cells is still unclear. Of the in situ hybridization signals of twelve members of the clc Cl(-) channel family, only that of clc-2c exhibited an ionocyte pattern in the gill and embryonic skin. Double in situ hybridization/immunocytochemistry confirmed colocalization of apical NCC2b with basolateral CLC-2c. Acclimation to a low Cl(-) environment increased mRNA expression of both clc-2c and ncc2b, and also the protein expression of CLC-2c in embryos and adult gills. Loss-of-function of clc-2c resulted in a significant decrease in whole body Cl(-) content in zebrafish embryos, a phenotype similar to that of ncc2b mutants; this finding suggests a role for CLC-2c in Cl(-) uptake. Translational knockdown of clc-2c stimulated ncc2b mRNA expression and vice versa, revealing cooperation between these two transporters in the context of zebrafish Cl(-) homeostasis. Further comparative genomic and phylogenetic analyses revealed that zebrafish CLC-2c is a fish-specific isoform that diverged from a kidney-predominant homologue, in the same manner as NCC2b and its counterparts (NCCs). Several lines of molecular and cellular physiological evidences demonstrated the cofunctional role of apical NCC2b and basolateral CLC-2c in the gill/skin Cl(-) uptake pathway. Taking the phylogenetic evidence into consideration, fish-specific NCC2b and CLC-2c may have coevolved to perform extra-renal Cl(-) uptake during the evolution of vertebrates in an aquatic environment. PMID:26327813

  8. Molecular Physiology of an Extra-renal Cl- Uptake Mechanism for Body Fluid Cl- Homeostasis

    PubMed Central

    Wang, Yi-Fang; Yan, Jia-Jiun; Tseng, Yung-Che; Chen, Ruo-Dong; Hwang, Pung-Pung

    2015-01-01

    The development of an ion regulatory mechanism for body fluid homeostasis was an important trait for vertebrates during the evolution from aquatic to terrestrial life. The homeostatic mechanism of Cl- in aquatic fish appears to be similar to that of terrestrial vertebrates; however, the mechanism in non-mammalian vertebrates is poorly understood. Unlike in mammals, in which the kidney plays a central role, in most fish species, the gill is responsible for the maintenance of Cl- homeostasis via Cl- transport uptake mechanisms. Previous studies in zebrafish identified Na+-Cl- cotransporter (NCC) 2b-expressing cells in the gills and skin as the major ionocytes responsible for Cl- uptake, similar to distal convoluted tubular cells in mammalian kidney. However, the mechanism by which basolateral ions exit from NCC cells is still unclear. Of the in situ hybridization signals of twelve members of the clc Cl- channel family, only that of clc-2c exhibited an ionocyte pattern in the gill and embryonic skin. Double in situ hybridization/immunocytochemistry confirmed colocalization of apical NCC2b with basolateral CLC-2c. Acclimation to a low Cl- environment increased mRNA expression of both clc-2c and ncc2b, and also the protein expression of CLC-2c in embryos and adult gills. Loss-of-function of clc-2c resulted in a significant decrease in whole body Cl- content in zebrafish embryos, a phenotype similar to that of ncc2b mutants; this finding suggests a role for CLC-2c in Cl- uptake. Translational knockdown of clc-2c stimulated ncc2b mRNA expression and vice versa, revealing cooperation between these two transporters in the context of zebrafish Cl- homeostasis. Further comparative genomic and phylogenetic analyses revealed that zebrafish CLC-2c is a fish-specific isoform that diverged from a kidney-predominant homologue, in the same manner as NCC2b and its counterparts (NCCs). Several lines of molecular and cellular physiological evidences demonstrated the cofunctional role of apical NCC2b and basolateral CLC-2c in the gill/skin Cl- uptake pathway. Taking the phylogenetic evidence into consideration, fish-specific NCC2b and CLC-2c may have coevolved to perform extra-renal Cl- uptake during the evolution of vertebrates in an aquatic environment. PMID:26327813

  9. Exoskeletal chitin scales isometrically with body size in terrestrial insects.

    PubMed

    Lease, Hilary M; Wolf, Blair O

    2010-06-01

    The skeletal system of animals provides the support for a variety of activities and functions. For animals such as mammals, which have endoskeletons, research has shown that skeletal investment (mass) scales with body mass to the 1.1 power. In this study, we ask how exoskeletal investment in insects scales with body mass. We measured the body mass and mass of exoskeletal chitin of 551 adult terrestrial insects of 245 species, with dry masses ranging from 0.0001 to 2.41 g (0.0002-6.13 g wet mass) to assess the allometry of exoskeletal investment. Our results showed that exoskeletal chitin mass scales isometrically with dry body mass across the Insecta as M(chitin) = a M(dry) (b), where b = 1.03 +/- 0.04, indicating that both large and small terrestrial insects allocate a similar fraction of their body mass to chitin. This isometric chitin-scaling relationship was also evident at the taxonomic level of order, for all insect orders except Coleoptera. We additionally found that the relative exoskeletal chitin investment, indexed by the coefficient, a, varies with insect life history and phylogeny. Exoskeletal chitin mass tends to be proportionally less and to increase at a lower rate with mass in flying than in nonflying insects (M(flying insect chitin) = -0.56 x M(dry) (0.97); M(nonflying insect chitin) = -0.55 x M(dry) (1.03)), and to vary with insect order. Isometric scaling (b = 1) of insect exoskeletal chitin suggests that the exoskeleton in insects scales differently than support structures of most other organisms, which have a positive allometry (b > 1) (e.g., vertebrate endoskeleton, tree secondary tissue). The isometric pattern that we document here additionally suggests that exoskeletal investment may not be the primary limit on insect body size. PMID:20235123

  10. Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

    PubMed Central

    Tucker, Marlee A.; Rogers, Tracey L.

    2014-01-01

    Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. PMID:25377460

  11. Examining predator-prey body size, trophic level and body mass across marine and terrestrial mammals.

    PubMed

    Tucker, Marlee A; Rogers, Tracey L

    2014-12-22

    Predator-prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator-prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator-prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator-prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. PMID:25377460

  12. The evolution of maximum body size of terrestrial mammals.

    PubMed

    Smith, Felisa A; Boyer, Alison G; Brown, James H; Costa, Daniel P; Dayan, Tamar; Ernest, S K Morgan; Evans, Alistair R; Fortelius, Mikael; Gittleman, John L; Hamilton, Marcus J; Harding, Larisa E; Lintulaakso, Kari; Lyons, S Kathleen; McCain, Christy; Okie, Jordan G; Saarinen, Juha J; Sibly, Richard M; Stephens, Patrick R; Theodor, Jessica; Uhen, Mark D

    2010-11-26

    The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved. PMID:21109666

  13. Strategic considerations in SETI, and a microwave approach. [Search for ExtraTerrestrial Intelligence

    NASA Technical Reports Server (NTRS)

    Seeger, C. L.

    1977-01-01

    Plausible options in the search for extraterrestrial intelligence (SETI), and the need to reserve a suitable portion of the EM (microwave) spectrum for SETI research, are discussed. Reasons for selection of a portion of the spectrum, specifically the 'water hole' near 1.5 GHz in the terrestrial microwave window (1-25 GHz), are presented, and competition with various emitters for that band (existing satellite downlink transmissions) is discussed. SETI search policies and options are summarized in a table. Speculative considerations guiding initial phases of the SETI pursuit are discussed.

  14. Extra-terrestrial life in the European Space Agency's Cosmic Vision plan and beyond.

    PubMed

    Fridlund, Malcolm

    2011-02-13

    Our exciting time allows us to contemplate the moment in the not-too-distant future when we can detect the presence of life on worlds orbiting stars other than our Sun. It will not be easy and will require the development and use of the very latest technologies. It also very probably demands deployment in space of relevant instrumentation in order to carry out these investigations. The European Space Agency has been involved in the studies and development of the required technologies for more than a decade and is currently formulating a roadmap for how to achieve the ultimate detection of signs of life as we know it on terrestrial exoplanets. The major elements of the roadmap consist of the following. First, the search for and detection of terrestrial exoplanets. Here, some progress has been made recently and is reported in this paper. Second, the more and more detailed study of the physical characteristics of such exoplanets. Finally, the search for biomarkers--indicators of biological activity--that can be observed at interstellar distances. The last is probably one of the most difficult problems ever contemplated by observational astronomy. PMID:21220282

  15. First stage identification of syntactic elements in an extra-terrestrial signal

    NASA Astrophysics Data System (ADS)

    Elliott, John

    2011-02-01

    By investigating the generic attributes of a representative set of terrestrial languages at varying levels of abstraction, it is our endeavour to try and isolate elements of the signal universe, which are computationally tractable for its detection and structural decipherment. Ultimately, our aim is to contribute in some way to the understanding of what 'languageness' actually is. This paper describes algorithms and software developed to characterise and detect generic intelligent language-like features in an input signal, using natural language learning techniques: looking for characteristic statistical "language-signatures" in test corpora. As a first step towards such species-independent language-detection, we present a suite of programs to analyse digital representations of a range of data, and use the results to extrapolate whether or not there are language-like structures which distinguish this data from other sources, such as music, images, and white noise.

  16. Estimating terrestrial amphibian pesticide body burden through dermal exposure

    EPA Science Inventory

    Dermal exposure presents a potentially significant but understudied route for pesticide uptake in terrestrial amphibians. Our study measured dermal uptake of pesticides of varying hydrophobicity (logKow) in frogs. Amphibians were indirectly exposed to one of five pesticide active...

  17. Migration of Icy Bodies to the Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Sergei, I. I.; Mather, J. C.; Marov, M. Y.

    2006-05-01

    In our opinion [1-2], some trans-Neptunian objects (TNOs) and planetesimals in the feeding zone of the giant planets with diameters up to 1000 km could be formed directly by the compression of large rarefied dust condensations, but not by the accretion of smaller solid planetesimals. Migration processes of small bodies from the outer regions of the solar system, including the Edgeworth-Kuiper belt, could be responsible for the delivery of the original matter (mainly volatiles) to the terrestrial planets and thus to give rise to the life origin. As migration of TNOs to Jupiter's orbit was studied by several authors, we integrated the orbital evolution of 30,000 Jupiter-crossing objects under the gravitational influence of planets [3]. A few considered objects got Earth-crossing orbits with aphelion distances Q<4.2 AU and moved in such orbits for more than 1 Myr (up to tens or even hundreds of Myrs). Collisions of cometary objects with the terrestrial planets from the Encke- type orbits with aphelia located inside the orbit of Jupiter are assumed to play a greater role than direct impacts from the Jupiter-crossing orbits. It may be possible that the fraction of 1-km former TNOs among near- Earth objects (NEOs) can exceed several tens of percents or most of former TNOs that had got NEO orbits disintegrated into mini-comets and dust during a smaller part of their dynamical lifetimes if these lifetimes are not small. Our estimates show that the amount of icy planetesimals impacted on the Earth during formation of the giant planets is of the order of mass of water in the Earth oceans if the total mass of these planetesimals was about 100 Earth masses. Mars acquired more water per unit of mass of a planet than Earth. During the following 4 Gyr the effectiveness of transport was much less. We integrated [4-5] the orbital evolution of 12,000 dust particles. Probabilites of collisions of particles started from Jupiter-family comets were maximum at diameter d about 100 microns and can be smaller by several orders of magnitude for other d. These maximum probabilities can be 1-2 orders of magnitude greater than the probabilities for comets which produced these particles. The dust particles could be most efficient in the delivery of organic or even biogenic matter to the Earth, because they experience substantially weaker heating when passing through the atmosphere [6]. References: [1] Ipatov S.I. (2001) LPSC, #1165. [2] Ipatov S.I. (2004) "The Search for Other Worlds", ed. by S.S. Holt and D. Deming, AIP Conference Proceedings, 713, 277-280. [3] Ipatov S.I. and Mather J.C. (2004) Annals of the New York Acad. of Sciences, 1017, 46-65. [4] Ipatov S.I., Mather J.C., and Taylor P. (2004) Annals of the New York Acad. of Sciences, 1017, 66-80. [5] Ipatov S.I. and Mather J.C. (2006) Advances in Space Research, in press. [6] Marov M.Ya. and Ipatov S.I. (2005) Solar System Research, 39, 374-380.

  18. Imprinted expression in cystic embryoid bodies shows an embryonic and not an extra-embryonic pattern.

    PubMed

    Kulinski, Tomasz M; Casari, M Rita T; Guenzl, Philipp M; Wenzel, Daniel; Andergassen, Daniel; Hladik, Anastasiya; Datlinger, Paul; Farlik, Matthias; Theussl, H-Christian; Penninger, Josef M; Knapp, Sylvia; Bock, Christoph; Barlow, Denise P; Hudson, Quanah J

    2015-06-15

    A large subset of mammalian imprinted genes show extra-embryonic lineage (EXEL) specific imprinted expression that is restricted to placental trophectoderm lineages and to visceral yolk sac endoderm (ysE). Isolated ysE provides a homogenous in vivo model of a mid-gestation extra-embryonic tissue to examine the mechanism of EXEL-specific imprinted gene silencing, but an in vitro model of ysE to facilitate more rapid and cost-effective experiments is not available. Reports indicate that ES cells differentiated into cystic embryoid bodies (EBs) contain ysE, so here we investigate if cystic EBs model ysE imprinted expression. The imprinted expression pattern of cystic EBs is shown to resemble fetal liver and not ysE. To investigate the reason for this we characterized the methylome and transcriptome of cystic EBs in comparison to fetal liver and ysE, by whole genome bisulphite sequencing and RNA-seq. Cystic EBs show a fetal liver pattern of global hypermethylation and low expression of repeats, while ysE shows global hypomethylation and high expression of IAPEz retroviral repeats, as reported for placenta. Transcriptome analysis confirmed that cystic EBs are more similar to fetal liver than ysE and express markers of early embryonic endoderm. Genome-wide analysis shows that ysE shares epigenetic and repeat expression features with placenta. Contrary to previous reports, we show that cystic EBs do not contain ysE, but are more similar to the embryonic endoderm of fetal liver. This explains why cystic EBs reproduce the imprinted expression seen in the embryo but not that seen in the ysE. PMID:25912690

  19. Imprinted expression in cystic embryoid bodies shows an embryonic and not an extra-embryonic pattern

    PubMed Central

    Kulinski, Tomasz M.; Casari, M. Rita T.; Guenzl, Philipp M.; Wenzel, Daniel; Andergassen, Daniel; Hladik, Anastasiya; Datlinger, Paul; Farlik, Matthias; Theussl, H. -Christian; Penninger, Josef M.; Knapp, Sylvia; Bock, Christoph; Barlow, Denise P.; Hudson, Quanah J.

    2015-01-01

    A large subset of mammalian imprinted genes show extra-embryonic lineage (EXEL) specific imprinted expression that is restricted to placental trophectoderm lineages and to visceral yolk sac endoderm (ysE). Isolated ysE provides a homogenous in vivo model of a mid-gestation extra-embryonic tissue to examine the mechanism of EXEL-specific imprinted gene silencing, but an in vitro model of ysE to facilitate more rapid and cost-effective experiments is not available. Reports indicate that ES cells differentiated into cystic embryoid bodies (EBs) contain ysE, so here we investigate if cystic EBs model ysE imprinted expression. The imprinted expression pattern of cystic EBs is shown to resemble fetal liver and not ysE. To investigate the reason for this we characterized the methylome and transcriptome of cystic EBs in comparison to fetal liver and ysE, by whole genome bisulphite sequencing and RNA-seq. Cystic EBs show a fetal liver pattern of global hypermethylation and low expression of repeats, while ysE shows global hypomethylation and high expression of IAPEz retroviral repeats, as reported for placenta. Transcriptome analysis confirmed that cystic EBs are more similar to fetal liver than ysE and express markers of early embryonic endoderm. Genome-wide analysis shows that ysE shares epigenetic and repeat expression features with placenta. Contrary to previous reports, we show that cystic EBs do not contain ysE, but are more similar to the embryonic endoderm of fetal liver. This explains why cystic EBs reproduce the imprinted expression seen in the embryo but not that seen in the ysE. PMID:25912690

  20. Wet tropospheric delay spatial variability over terrestrial water bodies

    NASA Astrophysics Data System (ADS)

    Clark, E.; Moller, D.; Andreadis, K.; Lettenmaier, D. P.

    2013-12-01

    Among the sources of uncertainty in radar altimetry measurements of inland water bodies is the signal delay associated with space-time variations in water vapor in the atmosphere. Over the ocean, zenith wet tropospheric path delays (PD) can be measured by satellite microwave radiometry; however, the high brightness temperature of land prevents the use of these techniques over inland waters. SAR-based Atmospheric Phase Screens can be estimated over land, but not over water bodies. Radiosonde- and GPS-based estimates of PD over land are available, yet these measurements occur at specific, sparse locations. Atmospheric models are therefore the best source of information about space-time variations in PD, where observations (e.g., from radiosonde and GPS) are incorporated via data assimilation. The upcoming Surface Water and Ocean Topography mission (SWOT) will use Interferometric Synthetic Aperture Radar (InSAR) in Ka-band, at a high incidence angle, to measure temporal variations in water elevation, slope, and extent in rivers, lakes, and reservoirs. Images will be collected over a 120-km wide swath with <100 m spatial resolution and ~1 cm height precision when averaged over a 1 km2 area, with a 21-day repeat cycle. At present, the spatial and temporal variability of PD at spatial scales relevant to the mission's inland water objectives (e.g., measurement of variations in the storage of reservoirs and lakes with spatial extent order 1 sq. km and larger) is an open question. We report the results of simulations of PD based on simulations from the Weather Research and Forecasting (WRF) numerical weather prediction model. We consider two domains within the continental U.S.: 1) the Pacific Northwest (at 4-km and 4/3-km spatial resolutions, via WRF results provided by the Northwest Modeling Consortium), and 2) sections of New Mexico, Oklahoma, and Texas (at 2.33-km spatial resolution, via simulations performed for this study). We then investigate the spatial and temporal variability of these PD values over inland water bodies, with a focus on manmade reservoirs in the Western U.S., including Anderson Ranch, Ray Hubbard, Elephant Butte, Lake Mead, and Sam Rayburn. We also assess the degree of temporal correlation between PD and water level variations and spatial correlations between PD and water extent variations.

  1. Crater size estimates for large-body terrestrial impact

    NASA Technical Reports Server (NTRS)

    Schmidt, Robert M.; Housen, Kevin R.

    1988-01-01

    Calculating the effects of impacts leading to global catastrophes requires knowledge of the impact process at very large size scales. This information cannot be obtained directly but must be inferred from subscale physical simulations, numerical simulations, and scaling laws. Schmidt and Holsapple presented scaling laws based upon laboratory-scale impact experiments performed on a centrifuge (Schmidt, 1980 and Schmidt and Holsapple, 1980). These experiments were used to develop scaling laws which were among the first to include gravity dependence associated with increasing event size. At that time using the results of experiments in dry sand and in water to provide bounds on crater size, they recognized that more precise bounds on large-body impact crater formation could be obtained with additional centrifuge experiments conducted in other geological media. In that previous work, simple power-law formulae were developed to relate final crater diameter to impactor size and velocity. In addition, Schmidt (1980) and Holsapple and Schmidt (1982) recognized that the energy scaling exponent is not a universal constant but depends upon the target media. Recently, Holsapple and Schmidt (1987) includes results for non-porous materials and provides a basis for estimating crater formation kinematics and final crater size. A revised set of scaling relationships for all crater parameters of interest are presented. These include results for various target media and include the kinematics of formation. Particular attention is given to possible limits brought about by very large impactors.

  2. A universal scaling relationship between body mass and proximal limb bone dimensions in quadrupedal terrestrial tetrapods

    PubMed Central

    2012-01-01

    Background Body size is intimately related to the physiology and ecology of an organism. Therefore, accurate and consistent body mass estimates are essential for inferring numerous aspects of paleobiology in extinct taxa, and investigating large-scale evolutionary and ecological patterns in the history of life. Scaling relationships between skeletal measurements and body mass in birds and mammals are commonly used to predict body mass in extinct members of these crown clades, but the applicability of these models for predicting mass in more distantly related stem taxa, such as non-avian dinosaurs and non-mammalian synapsids, has been criticized on biomechanical grounds. Here we test the major criticisms of scaling methods for estimating body mass using an extensive dataset of mammalian and non-avian reptilian species derived from individual skeletons with live weights. Results Significant differences in the limb scaling of mammals and reptiles are noted in comparisons of limb proportions and limb length to body mass. Remarkably, however, the relationship between proximal (stylopodial) limb bone circumference and body mass is highly conserved in extant terrestrial mammals and reptiles, in spite of their disparate limb postures, gaits, and phylogenetic histories. As a result, we are able to conclusively reject the main criticisms of scaling methods that question the applicability of a universal scaling equation for estimating body mass in distantly related taxa. Conclusions The conserved nature of the relationship between stylopodial circumference and body mass suggests that the minimum diaphyseal circumference of the major weight-bearing bones is only weakly influenced by the varied forces exerted on the limbs (that is, compression or torsion) and most strongly related to the mass of the animal. Our results, therefore, provide a much-needed, robust, phylogenetically corrected framework for accurate and consistent estimation of body mass in extinct terrestrial quadrupeds, which is important for a wide range of paleobiological studies (including growth rates, metabolism, and energetics) and meta-analyses of body size evolution. PMID:22781121

  3. Terrestrial soft-bodied protists and other microorganisms in triassic amber.

    PubMed

    Poinar, G O; Waggoner, B M; Bauer, U C

    1993-01-01

    Protozoa, cyanobacteria, sheathed algae, sheathed fungi, germinating pollen or spores, and fungal spores have been found in amber 220 to 230 million years old. Many of these microorganisms can be assigned to present-day groups. This discovery of terrestrial, soft-bodied protists that can be referred to modern groups indicates that morphological evolution is very gradual in many protists and that both structural and probably functional stasis extend back at least to the Upper Triassic period. PMID:17790989

  4. Body shape in terrestrial isopods: A morphological mechanism to resist desiccation?

    PubMed

    Broly, Pierre; Devigne, Cédric; Deneubourg, Jean-Louis

    2015-11-01

    Woodlice are fully terrestrial crustaceans and are known to be sensitive to water loss. Their half-ellipsoidal shapes represent simple models in which to investigate theoretical assumptions about organism morphology and rates of exchange with the environment. We examine the influence of surface area and mass on the desiccation rates in three eco-morphologically different species of woodlice: Oniscus asellus, Porcellio scaber, and Armadillidium vulgare. Our analysis indicates that the rate of water loss of an individual depends on both the initial weight and the body surface area. Interspecific and intraspecific analyses show that the mass-specific water loss rate of a species decreases along with the ratio of surface area to volume. In particular, we show that body shape explains the difference in mass-specific water loss rates between A. vulgare and P. scaber. This observation also explains several known ecological patterns, for example, the distribution and survivorship of individuals. However, in addition to body size and shape, water loss in terrestrial isopods depends also on the coefficient of permeability (i.e., a measure of water loss rate per surface unit), which is high in O. asellus and lower (and at similar levels) in P. scaber and A. vulgare. We discuss morphological, physiological, and behavioral aspects of water loss avoidance in terrestrial isopods. PMID:26289755

  5. The Combined Strength of Thermodynamics and Comparative Planetology: Application of Activity Models to Core Formation in Terrestrial Bodies

    NASA Astrophysics Data System (ADS)

    Righter, K.; Pando, K. M.; Danielson, L. R.

    2015-07-01

    We combine our new data on the effect of Si and C on metal-silicate partitioning of volatile elements Ge, In, As, and Sb with previous results to produce a model that can be applied to any terrestrial body.

  6. Application of an axisymmetric implicit blunt body procedure - Computation of solar wind flows past terrestrial planets

    NASA Technical Reports Server (NTRS)

    Chaussee, D. S.; Stahara, S. S.; Spreiter, J. R.

    1977-01-01

    A recently developed axisymmetric implicit unsteady Euler equation solver has been applied to the calculation of solar wind flows past terrestrial planets. The primary emphasis of this paper is on the application of that computational technique to the calculation of the flow field properties of steady, axisymmetric, supersonic/hypersonic flows past blunt-nosed shapes characteristic of interplanetary solar wind flows past both magnetic and nonmagnetic planets. The purpose is to demonstrate both the accuracy and flexibility of this new technique as well as to present a novel application of such supersonic blunt-body procedures.

  7. Quantitative Trait Loci for Light Sensitivity, Body Weight, Body Size, and Morphological Eye Parameters in the Bumblebee, Bombus terrestris.

    PubMed

    Maebe, Kevin; Meeus, Ivan; De Riek, Jan; Smagghe, Guy

    2015-01-01

    Bumblebees such as Bombus terrestris are essential pollinators in natural and managed ecosystems. In addition, this species is intensively used in agriculture for its pollination services, for instance in tomato and pepper greenhouses. Here we performed a quantitative trait loci (QTL) analysis on B. terrestris using 136 microsatellite DNA markers to identify genes linked with 20 traits including light sensitivity, body size and mass, and eye and hind leg measures. By composite interval mapping (IM), we found 83 and 34 suggestive QTLs for 19 of the 20 traits at the linkage group wide significance levels of p = 0.05 and 0.01, respectively. Furthermore, we also found five significant QTLs at the genome wide significant level of p = 0.05. Individual QTLs accounted for 7.5-53.3% of the phenotypic variation. For 15 traits, at least one QTL was confirmed with multiple QTL model mapping. Multivariate principal components analysis confirmed 11 univariate suggestive QTLs but revealed three suggestive QTLs not identified by the individual traits. We also identified several candidate genes linked with light sensitivity, in particular the Phosrestin-1-like gene is a primary candidate for its phototransduction function. In conclusion, we believe that the suggestive and significant QTLs, and markers identified here, can be of use in marker-assisted breeding to improve selection towards light sensitive bumblebees, and thus also the pollination service of bumblebees. PMID:25928544

  8. Quantitative Trait Loci for Light Sensitivity, Body Weight, Body Size, and Morphological Eye Parameters in the Bumblebee, Bombus terrestris

    PubMed Central

    Maebe, Kevin; Meeus, Ivan; De Riek, Jan; Smagghe, Guy

    2015-01-01

    Bumblebees such as Bombus terrestris are essential pollinators in natural and managed ecosystems. In addition, this species is intensively used in agriculture for its pollination services, for instance in tomato and pepper greenhouses. Here we performed a quantitative trait loci (QTL) analysis on B. terrestris using 136 microsatellite DNA markers to identify genes linked with 20 traits including light sensitivity, body size and mass, and eye and hind leg measures. By composite interval mapping (IM), we found 83 and 34 suggestive QTLs for 19 of the 20 traits at the linkage group wide significance levels of p = 0.05 and 0.01, respectively. Furthermore, we also found five significant QTLs at the genome wide significant level of p = 0.05. Individual QTLs accounted for 7.5-53.3% of the phenotypic variation. For 15 traits, at least one QTL was confirmed with multiple QTL model mapping. Multivariate principal components analysis confirmed 11 univariate suggestive QTLs but revealed three suggestive QTLs not identified by the individual traits. We also identified several candidate genes linked with light sensitivity, in particular the Phosrestin-1-like gene is a primary candidate for its phototransduction function. In conclusion, we believe that the suggestive and significant QTLs, and markers identified here, can be of use in marker-assisted breeding to improve selection towards light sensitive bumblebees, and thus also the pollination service of bumblebees. PMID:25928544

  9. Extra Terrestrial Environmental Chamber Design

    NASA Technical Reports Server (NTRS)

    Hughes, David W.

    2008-01-01

    A vacuum chamber designed to simulate the dusty environment on the Moon or Mars has been built for Goddard Space Flight Center. The path from concept to delivery is reviewed, with lessons learned and pitfalls highlighted along the way.

  10. Terrestrial models for development of methods to search for life on Mars and other planetary bodies

    NASA Astrophysics Data System (ADS)

    Abyzov, S. S.; Duxbury, N. S.; Fukuchi, M.; Hoover, R. B.; Kanda, H.; Mitskevich, I. N.; Mulyukin, A. L.; Naganuma, T.; Poglazova, M. N.; Ivanov, M. V.

    Successful missions to Mars, Europa and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost habitats as terrestrial analogues. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the most ancient and deepest strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radiolabeling and other techniques made it possible for us to obtain a convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future search for microbial life and/or its biosignatures on extraterrestrial objects.

  11. Body mass explains characteristic scales of habitat selection in terrestrial mammals

    PubMed Central

    Fisher, Jason T; Anholt, Brad; Volpe, John P

    2011-01-01

    Niche theory in its various forms is based on those environmental factors that permit species persistence, but less work has focused on defining the extent, or size, of a species environment: the area that explains a species presence at a point in space. We proposed that this habitat extent is identifiable from a characteristic scale of habitat selection, the spatial scale at which habitat best explains species occurrence. We hypothesized that this scale is predicted by body size. We tested this hypothesis on 12 sympatric terrestrial mammal species in the Canadian Rocky Mountains. For each species, habitat models varied across the 20 spatial scales tested. For six species, we found a characteristic scale; this scale was explained by species body mass in a quadratic relationship. Habitat measured at large scales best-predicted habitat selection in both large and small species, and small scales predict habitat extent in medium-sized species. The relationship between body size and habitat selection scale implies evolutionary adaptation to landscape heterogeneity as the driver of scale-dependent habitat selection. PMID:22393519

  12. Syntax diagrams for body wave nomenclature, with generalizations for terrestrial planets

    NASA Astrophysics Data System (ADS)

    Knapmeyer, M.

    2003-04-01

    The Apollo network on the Moon constitutes the beginning of planetary seismology. In the next few decades, we may see seismometers deployed on the Moon again, on Mars, and perhaps on other terrestrial planets or satellites. Any seismological software for computation of body wave travel times on other planets should be highly versatile and be prepared for a huge variety of velocity distributions and internal structures. A suite of trial models for a planet might, for example, contain models with and without solid inner cores. It would then be useful if the software could detect physically meaningless phase names automatically without actually carrying out any computation. It would also be useful if the program were prepared to deal with features like fully solid cores, internal oceans, and varying depths of mineralogical phase changes like the olivine-spinel transition. Syntax diagrams are a standard method to describe the syntax of programming languages. They represent a graphical way to define which letter or phrase is allowed to follow a given sequence of letters. Syntax diagrams may be stored in data structures that allow automatic evaluation of a given letter sequence. Such diagrams are presented here for a generalized body wave nomenclature. Generalizations are made to overcome earth-specific notations which incorporate discontinuity depths into phase names or to distinguish olivine transitions from ice-ice transitions (as expected on the Galilean Satellites).

  13. N-body simulations of terrestrial planet formation under the influence of a hot Jupiter

    SciTech Connect

    Ogihara, Masahiro; Kobayashi, Hiroshi; Inutsuka, Shu-ichiro E-mail: ogihara@nagoya-u.jp

    2014-06-01

    We investigate the formation of multiple-planet systems in the presence of a hot Jupiter (HJ) using extended N-body simulations that are performed simultaneously with semianalytic calculations. Our primary aims are to describe the planet formation process starting from planetesimals using high-resolution simulations, and to examine the dependences of the architecture of planetary systems on input parameters (e.g., disk mass, disk viscosity). We observe that protoplanets that arise from oligarchic growth and undergo type I migration stop migrating when they join a chain of resonant planets outside the orbit of an HJ. The formation of a resonant chain is almost independent of our model parameters, and is thus a robust process. At the end of our simulations, several terrestrial planets remain at around 0.1 AU. The formed planets are not equal mass; the largest planet constitutes more than 50% of the total mass in the close-in region, which is also less dependent on parameters. In the previous work of this paper, we have found a new physical mechanism of induced migration of the HJ, which is called a crowding-out. If the HJ opens up a wide gap in the disk (e.g., owing to low disk viscosity), crowding-out becomes less efficient and the HJ remains. We also discuss angular momentum transfer between the planets and disk.

  14. Extra Deimensions

    SciTech Connect

    Hill, Chris

    2009-10-03

    We describe recent ideas involving latticizing or "deconstructing" extra space time dimensions. Particles and geometry meld into the same thing. Intriguing topological beasts arise. Above all, new organizing principles for physics beyond the Standard Model come into view.

  15. The microbiome: the forgotten organ of the astronaut's body--probiotics beyond terrestrial limits.

    PubMed

    Saei, Amir Ata; Barzegari, Abolfazl

    2012-09-01

    Space medicine research has drawn immense attention toward provision of efficient life support systems during long-term missions into space. However, in extended missions, a wide range of diseases may affect astronauts. In space medicine research, the gastrointestinal microbiome and its role in maintaining astronauts' health has received little attention. We would like to draw researchers' attention to the significant role of microbiota. Because of the high number of microorganisms in the human body, man has been called a 'supra-organism' and gastrointestinal flora has been referred to as 'a virtual organ of the human body'. In space, the lifestyle, sterility of spaceship and environmental stresses can result in alterations in intestinal microbiota, which can lead to an impaired immunity and predispose astronauts to illness. This concern is heightened by increase in virulence of pathogens in microgravity. Thus, design of a personal probiotic kit is recommended to improve the health status of astronauts. PMID:22953705

  16. Influences of limb proportions and body size on locomotor kinematics in terrestrial primates and fossil hominins.

    PubMed

    Polk, J D

    2004-10-01

    During locomotion, mammalian limb postures are influenced by many factors including the animal's limb length and body mass. Polk (2002) compared the gait of similar-sized cercopithecine monkeys that differed limb proportions and found that longer-limbed monkeys usually adopt more extended joint postures than shorter-limbed monkeys in order to moderate their joint moments. Studies of primates as well as non-primate mammals that vary in body mass have demonstrated that larger animals use more extended limb postures than smaller animals. Such extended postures in larger animals increase the extensor muscle mechanical advantage and allow postures to be maintained with relatively less muscular effort (Polk, 2002; Biewener 1989). The results of these previous studies are used here to address two anthropological questions. The first concerns the postural effects of body mass and limb proportion differences between australopithecines and members of the genus Homo. That is, H. erectus and later hominins all have larger body mass and longer legs than australopithecines, and these anatomical differences suggest that Homo probably used more extended postures and probably required relatively less muscular force to resist gravity than the smaller and shorter-limbed australopithecines. The second question investigates how animals with similar size but different limb proportions differ in locomotor performance. The effects of limb proportions on gait are relevant to inferring postural and locomotor differences between Neanderthals and modern Homo sapiens which differ in their crural indices and relative limb length. This study demonstrates that primates with relatively long limbs achieve higher walking speeds while using lower stride frequencies and lower angular excursions than shorter-limbed monkeys, and these kinematic differences may allow longer-limbed taxa to locomote more efficiently than shorter-limbed species of similar mass. Such differences may also have characterized the gait of Homo sapiens in comparison to Neanderthals, but more experimental data on humans that vary in limb proportions are necessary in order to evaluate this question more thoroughly. PMID:15454335

  17. Combining N-body accretion simulations with partitioning experiments in a statistical model of terrestrial planet accretion and core formation

    NASA Astrophysics Data System (ADS)

    Fischer, R. A.; Ciesla, F.; Campbell, A. J.

    2014-12-01

    The terrestrial planets accreted in a series of increasingly large and violent collisions. Simultaneously, metallic cores segregated from their silicate mantles, acquiring their modern compositions through high pressure (P), high temperature (T) partitioning reactions. Here we present a model that couples these aspects of early planetary evolution, building on recent accretion simulations and experimental results. We have run 100 N-body simulations of terrestrial planet accretion, with Jupiter and Saturn on either circular (CJS) or eccentric (EJS) orbits, to gain insight into the statistics of this highly stochastic process (Fischer and Ciesla, 2014). An Earth (Mars) analogue forms in 84-92% (2-10%) of our simulations. We draw on our recent high P-T metal-silicate partitioning experiments of Ni, Co, V, Cr, Si, and O in a diamond anvil cell to 100 GPa and 5500 K. In our model, N-body simulations describe the delivery, masses, and original locations of planetary building blocks. As planets accrete, their core and mantle compositions are modified by high P-T reactions with each collision (Rubie et al., 2011). By utilizing a large number of N-body simulations, we obtain a statistical view and observe a wide range of outcomes. We use this model to predict the core compositions of Earth-like planets. For partial equilibration of the mantle at 50% of the core-mantle boundary (CMB) pressure, we find that their cores contain 6.9 ± 1.8 wt% Si and 4.8 ± 2.3 wt% O (Figure), with this uncertainty due entirely to variations in accretion history in our 100 simulations. This composition is consistent with the seismologically-inferred density of Earth's core, based on comparisons to high P-T equations of state (Fischer et al., 2011, 2014). Earth analogues experience 0.7 ± 0.1 or 0.9 ± 0.2 log units of oxidation during accretion in EJS or CJS simulations respectively, which is due to both the effects of high P-T partitioning and the temporal evolution of the Earth analogue's feeding zone. The model can reveal the relative importance of various accretionary processes, highlighting targets for future experimental and numerical studies. For example, changing the depth of partitioning to 70% of the CMB pressure leads to an increase of 1.7 ± 2.8 wt% Si and 2.2 ± 3.5 wt% O in Earth analogue cores, comparable to variations due to accretion history.

  18. Extra Dimensions

    SciTech Connect

    Hewett, J.

    2004-10-05

    The large separation between the weak scale {approx} 10{sup 3} GeV and the traditional scale of gravity--the Planck scale with M{sub PI} {approx} 10{sup 19} GeV--is one of the most puzzling aspects of nature. The origin of this large ratio, as well as its stability under radiative corrections, demands explanation. This is known as the hierarchy problem. One theoretical means of solving this problem is to introduce Supersymmetry. Alternatively one may hope to address the hierarchy by exploiting the geometry of space time. Specifically, recent theories involve the idea that the 3-spatial dimensions in which we live could be a 3-spatial-dimensional ''membrane'' embedded in a much larger extra dimensional space, and that the hierarchy is generated by the geometry of the additional dimensions. Such ideas have led to extra dimensional theories which have verifiable consequences at the TeV scale. Our knowledge of the weak and strong forces extends down to scales of {approx} (100 GeV){sup -1} (or of order 10{sup -15} mm). On the other hand, we have almost no knowledge of gravity at distances less than roughly a millimeter, as direct tests of the gravitational force at the smallest distances are based on torsion-balance experiments, which are mechanically limited. It is thus conceivable that gravity may behave quite differently from the 3-dimensional Newtonian theory at small distances. This leads to the possibility that matter and non-gravitational forces are confined to our 3-dimensional subspace, whereas gravity may propagate throughout a higher dimensional volume. In this case, the gauge forces are trapped within our 3-dimensional space, unaware of the extra dimensions, and maintain their usual behavior. Gravity, on the other hand, would no longer follow the inverse-square force law at distances smaller than the size of the extra dimensions, as the gravitational equivalent of Gauss' Law mandates that the gravitational field spreads out into the full spatial volume. Since Newton's Law must be reproduced at large distances, gravity must behave as if there were only three spatial dimensions for r&1 mm. This is achievable either by compactifying all the extra dimensions on circles, where the geometry of these dimensions is thus flat and the topology is that of a torus, or by using strong curvature effects in the extra dimensions. In the first case, Arkani-Hamed, Dimopoulos, and Dvali (ADD) [1,2] used this picture to generate the hierarchy by postulating a large volume for the extra dimensional space, building on earlier ideas in Refs. 3,4. In the latter case, the hierarchy can be established by a large curvature of the extra dimensions as demonstrated by Randall and Sundrum (RS) [5,6]. It is the relation of these models to the hierarchy which yields testable predictions at the TeV scale.

  19. Highest volcanoes on terrestrial planets and dwarf-planets adorn the deepest depressions of their respective bodies

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2015-10-01

    Four highest volcanoes of the inner solar system tower above four largest and deepest hemispheric depressions of the Earth, Moon, Mars, and Vesta. Of course, this is not a mere coincidence; behind of this fundamental fact stays an equally fundamental planetary regulation. The wave planetology based on elliptical keplerian orbits of cosmic bodies evoking their wave warping shows that the fundamental wave 1 inevitably produces hemispheric tectonic dichotomy. One hemisphere rises, the opposite falls. The uprising half increases its planetary radius and space and thus is intensively cut by numerous faults and rifts. The antipodean subsiding half decreases its radius and space and thus is intensively compacted and affected by folds and faults. Forming extra material finds its way out in form of volcanic ridges and volcanoes. The strongest compaction caused by the wave 1 subsidence produces most voluminous eruptions. That is why the relation exists between the largest and deepest hemispheric basins and the highest basic volcanoes having mantle roots [1-4]. On the Earth's Pacific Ocean floor stay the Hawaiian volcanoes; on the lunar Procellarum Ocean occurs Crater Copernicus (erroneously taken as an impact feature); Martian Vastitas Borealis is adorned with Olympus Mons; Vestan Reasilvia Basin (obviously tectonic not impact feature) has the central mountain -the highest volcanic peak in the Solar system (Fig. 1-4). A regular row of increasing heights of these largest volcanoes extends in the outward direction. A study of the dwarf-planet Ceres only begins(DAWN project). Already the first distant images of this globe about 950 km in diameter have shown that it is, as was predicted [5], tectonically two-faced or dichotomous body (Fig. 5, 6). It seems that on its relatively even subsided hemisphere there are some elevated locations often bright white in color (Fig. 6). They could represent prominent "edifices" covered with frozen ices -degassing traces [6].

  20. A Postulated Planetary Collision, the Terrestrial Planets, the Moon and Smaller Solar-System Bodies

    NASA Astrophysics Data System (ADS)

    Woolfson, M. M.

    2013-11-01

    In a scenario produced by the Capture Theory of planetary formation, a collision between erstwhile solar-system giant planets, of masses 798.75 and 598.37 M ?, is simulated using smoothed-particle hydrodynamics. Due to grain-surface chemistry that takes place in star-forming clouds, molecular species containing hydrogen, with a high D/H ratio taken as 0.01, form a layer around each planetary core. Temperatures generated by the collision initiate D-D reactions in these layers that, in their turn, trigger a reaction chain involving heavier elements. The nuclear explosion shatters and disperses both planets, leaving iron-plus-silicate stable residues identified as a proto-Venus and proto-Earth. A satellite of one of the colliding planets, captured or retained by the proto-Earth core, gave the Moon; two massive satellites released into heliocentric orbits became Mercury and Mars. For the Moon and Mars, abrasion of their surfaces exposed to collision debris results in hemispherical asymmetry. Mercury, having lost a large part of its mantle due to massive abrasion, reformed to give the present high-density body. Debris from the collision gave rise to asteroids and comets, much of the latter forming an inner reservoir stretching outwards from the inner Kuiper Belt that replenishes the Oort Cloud when it is depleted by a severe perturbation. Other features resulting from the outcome of the planetary collision are the relationship of Pluto and Triton to Neptune, the presence of dwarf planets and light-atom isotopic anomalies in meteorites.

  1. Searching for extra-terrestrial civilizations

    NASA Technical Reports Server (NTRS)

    Gindilis, L. M.

    1974-01-01

    The probability of radio interchange with extraterrestrial civilizations is discussed. Difficulties constitute absorption, scattering, and dispersion of signals by the rarified interstellar medium as well as the deciphering of received signals and convergence of semantic concept. A cybernetic approach considers searching for signals that develop from astroengineering activities of extraterrestrial civilizations.

  2. The Search for Extra-Terrestrial Intelligence

    NASA Astrophysics Data System (ADS)

    Tarter, J.

    1998-12-01

    Aliens abound on the movie screens, but in reality we are still trying to find out if we share our universe with other sentient creatures. Intelligence is very difficult to define, and impossible to directly detect over interstellar distances. Therefore, SETI, the search for extraterrestrial intelligence, is actually an attempt to detect evidence of another distant technology. If we find such evidence, we will infer the existence of intelligent technologists. For the past 36 years, the SETI community has had a very pragmatic definition of intelligence - the ability to build radio telescopes! Radio signals are not the only possible way to detect a technology across the vast distances that separate the stars, but given our own current technological state, it remains the best way.

  3. The Combined Strength of Thermodynamics and Comparative Planetology: Application of Activity Models to Core Formation in Terrestrial Bodies

    NASA Technical Reports Server (NTRS)

    Righter, K.; Pando, K. M.; Danielson, L. R.

    2015-01-01

    Recent models for accretion of terrestrial bodies involve metal-silicate equilibrium as the metallic core formed during growth. Most elements considered are either refractory or well studied elements for which effects of pressure, temperature, oxygen fugacity, and metallic liquid composition are well known. There are a large number of elements that are both siderophile and volatile, whose fate in such models is unknown, largely due to a lack of data at comparable conditions and com-positions (FeNi core with light elements such as S, C, Si, and O). We have focused on Ge, In, As, Sb and determined the effect of Si and C on metal-silicate partitioning, and developed a thermo-dynamic model that allows application of these new data to a wide range of planetary bodies. New experiments: We have previously carried out experiments with FeSi metallic liquid at C-saturated conditions at 1600 and 1800 C [4]. In a new series of experiments we investigate the effect of Si in carbon-free systems at 1600 C for comparison. Experiments were carried out at 1 GPa in MgO capsules using the same basaltic starting composition as in previous studies. The MgO capsule reacts with the silicate melt to form more MgO-rich liquids that have 22-26 wt% MgO. Experimental met-als and silicates were analyzed using a combination of electron microprobe analysis and laser ablation ICP-MS. Results: The new results can be interpreted by considering Ge as an example, in the simple exchange equilibrium Fe + GeO = FeO + Ge, where the equilibrium constant Kd can be examined as a function of Si content of the metal. The slope of lnKd vs. (1-XSi) for this new series allows derivation of the epsilon interaction parameter for each of these four elements and Si (both C-saturated and C-free).All four elements have positive epsilon values, indicating that Si causes a decrease in the partition coefficients; values are 6.6, 6.5, 27.8 and 25.2 for In, Ge, As, and Sb, respectively, at 1 GPa and 1600 C. As an example of how large the effect of Si can be, these epsilon values correspond to activity coefficients (gamma) for As of 0.01 when XSi = 0, and up to gamma = 23 when XSi = 0.2. Combining these new results with previous determinations [5,6] of epsilon parameters for S and C for these elements allows us calculate activity of Ge, In, As, and Sb in Fe-Ni-Si-S-C-O metallic liquids. We apply this new model to sever-al terrestrial bodies such as Earth (Si-rich core), Mars (S-rich core), Moon (S-, C-, and Si-poor core), and Vesta, and examine the resulting core and mantle concentrations of these elements. Mantle concentrations of these four elements are well explained for Earth and Mars in models that call for mid-mantle equilibration between Si-bearing and S-bearing FeNi cores, respectively. Modeling results for the Moon and Vesta will also be presented.

  4. Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Barlow, Nadine G.

    The four terrestrial planets (Mercury, Venus, Earth, and Mars) and Earth's Moon display similar compositions, interior structures, and geologic histories. The terrestrial planets formed by accretion 4.5 Ga ago out of the solar nebula, whereas the Moon formed through accretion of material ejected off Earth during a giant impact event shortly after Earth formed. Geophysical investigations (gravity anomalies, seismic analysis, heat flow measurements, and magnetic field studies) reveal that all five bodies have differentiated into a low-density silicate crust, an intermediate density silicate mantle, and an iron-rich core. Seismic and heat flow measurements are only available for Earth and its Moon, and only Earth and Mercury currently exhibit actively produced magnetic fields (although Mars and the Moon retain remanent fields). Surface evolutions of all five bodies have been influenced by impact cratering, volcanism, tectonism, and mass wasting. Aeolian activity only occurs on bodies with a substantial atmosphere (Venus, Earth, and Mars) and only Earth and Mars display evidence of fluvial and glacial processes. Earth's volcanic and tectonic activity is largely driven by plate tectonics, whereas those processes on Venus result from vertical motions associated with hotspots and mantle upwellings. Mercury displays a unique tectonic regime of global contraction caused by gradual solidification of its large iron core. Early large impact events stripped away much of Mercury's crust and mantle, produced Venus' slow retrograde rotation, ejected material off Earth that became the Moon, and may have created the Martian hemispheric dichotomy. The similarities and differences between the interiors and surfaces of these five bodies provide scientists with a better understanding of terrestrial planet evolutionary paths.

  5. U-Pb Composition and Shock Microstructures of In-Situ Accessory Phases Across the Vredefort Impact Structure, South Africa: A Terrestrial Analogue for Dating the Lunar Surface and Other Planetary Bodies

    NASA Astrophysics Data System (ADS)

    Davis, C. L.; Moser, D. E.

    2015-02-01

    Accessory phases (i.e. zircon, monazite) co-exist within individual samples of the Vredefort dome, with a dichotomy of U-Pb ages and microstructural evolution. Vredefort is a terrestrial analogue for complex craters on other planetary bodies.

  6. Late-stage accretion and habitability of terrestrial planets

    NASA Astrophysics Data System (ADS)

    Raymond, Sean Neylon

    The final stage in the formation of terrestrial planets consists of the accumulation of ~1000 km "planetary embryos" and ~1 km planetesimals via collisional accretion., under the mutual gravity of other solid bodies and the gas giant planets (if any). Water is delivered to planets via collisions with volatile-rich bodies that condensed past the snow line, beyond about 2.5 AU. We present results of a large number of relatively low-resolution simulations, designed to assess the predictability of systems of terrestrial planets as a function of "observables" such as the orbit of gas giant planets. These show that a variety of terrestrial planets can form, from small, dry, Mars-like worlds to planets with similar properties to Earth, to >3 Earth mass "water worlds" with >=30 times as much water as the Earth. The terrestrial planets are largely shaped by the influence of the giant planets and the surface density of material. We have uncovered trends between the terrestrial planets and (i) the mass, (ii) the orbital distance and (iii) the orbital eccentricity of a giant planet, (iv) the surface density of the disk, and (v) the disk's density profile. Five simulations with 1000-2000 particles reveal new aspects of the accretion process Water is delivered to the terrestrial planets as a few large planetesimals in a "hit or miss" process, and as billions of planetesimals in a robust way. The water delivery process is therefore more robust than previously thought, implying that the range of water contents of extra-solar Earths is less stochastic than indicated in previous studies; most planets accrete water- rich bodies. We simulate terrestrial accretion in the presence of close-in giant planets (e.g., "hot jupiters"), assuming these form and migrate quickly. Potentially habitable planets can form in these systems, but are likely to be iron-poor. Asteroid belts may exist between the terrestrial planets and hot jupiters in these systems. We have also tested the accretion process in four known extra- solar planetary systems. In 55 Cancri, terrestrial planets form relatively easily, and may have orbits in the habitable zone and significant water contents.

  7. Enrichment of Non-Terrestrial L-Proteinogenic Amino Acids by Aqueous Alteration on the Tagish Lake Meteorite Parent Body

    NASA Technical Reports Server (NTRS)

    Glavin, Daniel P.; Elsila, Jamie E.; Burton, Aaron S.; Callahan, Michael P.; Dworkin, Jason P.; Herd, Christopher D. K.

    2012-01-01

    The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography fluorescence detection time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approx. 43 to 59%) of the a-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha-hydrogen protein amino acid, was found to be nearly racemic (D approx. L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and D- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the meteorite. Alternate explanations for the Lexcesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals.

  8. ON THE EFFECT OF GIANT PLANETS ON THE SCATTERING OF PARENT BODIES OF IRON METEORITE FROM THE TERRESTRIAL PLANET REGION INTO THE ASTEROID BELT: A CONCEPT STUDY

    SciTech Connect

    Haghighipour, Nader; Scott, Edward R. D.

    2012-04-20

    In their model for the origin of the parent bodies of iron meteorites, Bottke et al. proposed differentiated planetesimals, formed in 1-2 AU during the first 1.5 Myr, as the parent bodies, and suggested that these objects and their fragments were scattered into the asteroid belt as a result of interactions with planetary embryos. Although viable, this model does not include the effect of a giant planet that might have existed or been growing in the outer regions. We present the results of a concept study where we have examined the effect of a planetary body in the orbit of Jupiter on the early scattering of planetesimals from the terrestrial region into the asteroid belt. We integrated the orbits of a large battery of planetesimals in a disk of planetary embryos and studied their evolutions for different values of the mass of the planet. Results indicate that when the mass of the planet is smaller than 10 M{sub Circled-Plus }, its effects on the interactions among planetesimals and planetary embryos are negligible. However, when the planet mass is between 10 and 50 M{sub Circled-Plus }, simulations point to a transitional regime with {approx}50 M{sub Circled-Plus} being the value for which the perturbing effect of the planet can no longer be ignored. Simulations also show that further increase of the mass of the planet strongly reduces the efficiency of the scattering of planetesimals from the terrestrial planet region into the asteroid belt. We present the results of our simulations and discuss their possible implications for the time of giant planet formation.

  9. Super-long Anabiosis of Ancient Microorganisms in Ice and Terrestrial Models for Development of Methods to Search for Life on Mars, Europa and other Planetary Bodies

    NASA Technical Reports Server (NTRS)

    Abyzov, S. S.; Duxbury, N. S.; Bobin, N. E.; Fukuchi, M.; Hoover, R. B.; Kanda, H.; Mitskevich, I. N.; Mulyukin, A. L.; Naganuma, T.; Poglazova, M. N.; Ivanov, M. V.

    2007-01-01

    Successful missions to Mars, Europe and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost as terrestrial analogues of Martian habitats. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the deepest and thus most ancient strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radioisotope labeling and other techniques made it possible for us to obtain convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication, we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future searches for microbial life and/or its biological signatures on extraterrestrial objects.

  10. Super-long anabiosis of ancient microorganisms in ice and terrestrial models for development of methods to search for life on Mars, Europa and other planetary bodies

    NASA Astrophysics Data System (ADS)

    Abyzov, S. S.; Duxbury, N. S.; Bobin, N. E.; Fukuchi, M.; Hoover, R. B.; Kanda, H.; Mitskevich, I. N.; Mulyukin, A. L.; Naganuma, T.; Poglazova, M. N.; Ivanov, M. V.

    2006-01-01

    Successful missions to Mars, Europe and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost as terrestrial analogues of Martian habitats. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the deepest and thus most ancient strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radioisotope labeling and other techniques made it possible for us to obtain convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication, we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future searches for microbial life and/or its biological signatures on extraterrestrial objects.

  11. Siderophile-element Anomalies in CK Carbonaceous Chondrites: Implications for Parent-body Aqueous Alteration and Terrestrial Weathering of Sulfides

    NASA Technical Reports Server (NTRS)

    Huber, Heinz; Rubin, Alan E.; Kallemeyn, Gregory W.; Wasson, John T.

    2006-01-01

    CK chondrites constitute the most oxidized anhydrous carbonaceous chondrite group; most of the Fe occurs in magnetite and in FeO-rich mafic silicates. The two observed CK falls (Karoonda and Kobe), along with thirteen relatively unweathered CK finds, have unfractionated siderophile-element abundance patterns. In contrast, a sizable fraction of CK finds (9 of 24 investigated) shows fractionated siderophile abundance patterns including low abundances of Ni, Co, Se and Au; the most extreme depletions are in Ni (0.24 of normal CK) and Au (0.14 of normal CK). This depletion pattern has not been found in other chondrite groups. Out of the 74 CK chondrites listed in the Meteoritical Bulletin Database (2006; excluded considerably paired specimens; see http://tin.er.usgs.gov/meteor/ metbull.php) we analyzed 24 and subclassified the CK chondrites in terms of their chemical composition and sulfide mineralogy: sL (siderophiles low; six samples) for large depletions in Ni, Co, Se and Au (>50% of sulfides lost); sM (siderophiles medium; two CKs) for moderately low Ni and Co abundances (sulfides are highly altered or partly lost); sH (siderophiles high; one specimen) for enrichments in Ni, Co, Se and Au; 'normal' for unfractionated samples (13 samples). The sole sH sample may have obtained additional sulfide from impact redistribution in the parent asteroid. We infer that these elements became incorporated into sulfides after asteroidal aqueous processes oxidized nebular metal; thermal metamorphism probably also played a role in their mineral siting. The siderophile losses in the SL and sM samples are mainly the result of oxidation of pentlandite, pyrite and violarite by terrestrial alteration followed by leaching of the resulting phases. Some Antarctic CK chondrites have lost most of their sulfides but retained Ni, Co, Se and Au, presumably as insoluble weathering products.

  12. ZO-1 and ZO-2 Are Required for Extra-Embryonic Endoderm Integrity, Primitive Ectoderm Survival and Normal Cavitation in Embryoid Bodies Derived from Mouse Embryonic Stem Cells

    PubMed Central

    Ali, Safiah Mohamed; Boey, Adrian; Gounko, Natalia V.; Hunziker, Walter

    2014-01-01

    The Zonula Occludens proteins ZO-1 and ZO-2 are cell-cell junction-associated adaptor proteins that are essential for the structural and regulatory functions of tight junctions in epithelial cells and their absence leads to early embryonic lethality in mouse models. Here, we use the embryoid body, an in vitro peri-implantation mouse embryogenesis model, to elucidate and dissect the roles ZO-1 and ZO-2 play in epithelial morphogenesis and de novo tight junction assembly. Through the generation of individual or combined ZO-1 and ZO-2 null embryoid bodies, we show that their dual deletion prevents tight junction formation, resulting in the disorganization and compromised barrier function of embryoid body epithelial layers. The disorganization is associated with poor microvilli development, fragmented basement membrane deposition and impaired cavity formation, all of which are key epithelial tissue morphogenetic processes. Expression of Podocalyxin, which positively regulates the formation of microvilli and the apical membrane, is repressed in embryoid bodies lacking both ZO-1 and ZO-2 and this correlates with an aberrant submembranous localization of Ezrin. The null embryoid bodies thus give an insight into how the two ZO proteins influence early mouse embryogenesis and possible mechanisms underlying the embryonic lethal phenotype. PMID:24905925

  13. Measuring feeding traits of a range of litter-consuming terrestrial snails: leaf litter consumption, faeces production and scaling with body size.

    PubMed

    Astor, Tina; Lenoir, Lisette; Berg, Matty P

    2015-07-01

    Plant litter decomposition is an essential ecosystem function that contributes to energy and nutrient cycling above- and belowground. Terrestrial gastropods can affect this process in various ways: they consume and fragment leaf litter and create suitable habitats for microorganisms through the production of faeces and mucus. We assessed the contributions of ten litter-feeding terrestrial snail species to leaf litter mass loss and checked whether consumption rate and faeces production scale with body size (i.e. shell size and shape), which may indicate that morphological traits can serve as proxies for consumption rate. Additionally, we compared the consumption rates of a subset of these species among litter types of two plant species which differ in resource quality (Fraxinus excelsior and Betula pendula). These snail species differed in their litter consumption rates. Consumption rates differed between the two litter types, whereas the rank order of litter consumption by the different species was independent of litter quality. Consumption rate and faeces production were positively related to shell size, whereas relative consumption rate and faeces production were related to shell shape, with more elongated snail species having lower relative consumption rates and faeces production rates. Our results show that easily measurable morphological traits scale with the feeding traits of snails, and represent useful proxies for consumption rate and faeces production, which are laborious to measure. Thus, estimated potential total consumption rates of snail communities along environmental gradients may be inferred from shell-size distributions. Our study contributes to a systematic trait-based evaluation of the importance of gastropods to litter decomposition. PMID:25698139

  14. The combination of conjugated linoleic acid (CLA) and extra virgin olive oil increases mitochondrial and body metabolism and prevents CLA-associated insulin resistance and liver hypertrophy in C57Bl/6 mice.

    PubMed

    Baraldi, Flávia G; Vicentini, Tatiane M; Teodoro, Bruno G; Dalalio, Felipe M; Dechandt, Carlos R P; Prado, Ieda M R; Curti, Carlos; Cardoso, Fernanda C; Uyemura, Sergio A; Alberici, Luciane C

    2016-02-01

    Clinical conditions associated with obesity can be improved by daily intake of conjugated linoleic acid (CLA) or extra virgin olive oil (EVOO). Here we investigated whether dietary supplementation with CLA and EVOO, either alone or in combination, changes body metabolism associated with mitochondrial energetics. Male C57Bl/6 mice were divided into one of four groups: CLA (1:1 cis-9, trans-11:trans-10, cis-12; 18:2 isomers), EVOO, CLA plus EVOO or control (linoleic acid). Each mouse received 3 g/kg body weight of the stated oil by gavage on alternating days for 60 days. Dietary supplementation with CLA, alone or in combination with EVOO: (a) reduced the white adipose tissue gain; (b) increased body VO2 consumption, VCO2 production and energy expenditure; (c) elevated uncoupling protein (UCP)-2 expression and UCP activity in isolated liver mitochondria. This organelle, when energized with NAD(+)-linked substrates, produced high amounts of H2O2 without inducing oxidative damage. Dietary supplementation with EVOO alone did not change any metabolic parameter, but supplementation with CLA itself promoted insulin resistance and elevated weight, lipid content and acetyl-CoA carboxylase-1 expression in liver. Interestingly, the in vivo antioxidant therapy with N-acetylcysteine abolished the CLA-induced rise of body metabolism and liver UCP expression and activity, while the in vitro antioxidant treatment with catalase mitigated the CLA-dependent UCP-2 expression in hepatocytes; these findings suggest the participation of an oxidative-dependent pathway. Therefore, this study clarifies the mechanisms by which CLA induces liver UCP expression and activity, and demonstrates for the first time the beneficial effects of combined CLA and EVOO supplementation. PMID:26878792

  15. Terrestrial sequestration

    SciTech Connect

    Charlie Byrer

    2008-03-10

    Terrestrial sequestration is the enhancement of CO2 uptake by plants that grow on land and in freshwater and, importantly, the enhancement of carbon storage in soils where it may remain more permanently stored. Terrestrial sequestration provides an opportunity for low-cost CO2 emissions offsets.

  16. Terrestrial sequestration

    ScienceCinema

    Charlie Byrer

    2010-01-08

    Terrestrial sequestration is the enhancement of CO2 uptake by plants that grow on land and in freshwater and, importantly, the enhancement of carbon storage in soils where it may remain more permanently stored. Terrestrial sequestration provides an opportunity for low-cost CO2 emissions offsets.

  17. Introduction to Extra Dimensions

    SciTech Connect

    Rizzo, Thomas G.; /SLAC

    2010-04-29

    Extra dimensions provide a very useful tool in addressing a number of the fundamental problems faced by the Standard Model. The following provides a very basic introduction to this very broad subject area as given at the VIII School of the Gravitational and Mathematical Physics Division of the Mexican Physical Society in December 2009. Some prospects for extra dimensional searches at the 7 TeV LHC with {approx}1 fb{sup -1} of integrated luminosity are provided.

  18. Debris disks as signposts of terrestrial planet formation

    NASA Astrophysics Data System (ADS)

    Raymond, S. N.; Armitage, P. J.; Moro-Martn, A.; Booth, M.; Wyatt, M. C.; Armstrong, J. C.; Mandell, A. M.; Selsis, F.; West, A. A.

    2011-06-01

    There exists strong circumstantial evidence from their eccentric orbits that most of the known extra-solar planetary systems are the survivors of violent dynamical instabilities. Here we explore the effect of giant planet instabilities on the formation and survival of terrestrial planets. We numerically simulate the evolution of planetary systems around Sun-like stars that include three components: (i) an inner disk of planetesimals and planetary embryos; (ii) three giant planets at Jupiter-Saturn distances; and (iii) an outer disk of planetesimals comparable to estimates of the primitive Kuiper belt. We calculate the dust production and spectral energy distribution of each system by assuming that each planetesimal particle represents an ensemble of smaller bodies in collisional equilibrium. Our main result is a strong correlation between the evolution of the inner and outer parts of planetary systems, i.e. between the presence of terrestrial planets and debris disks. Strong giant planet instabilities - that produce very eccentric surviving planets - destroy all rocky material in the system, including fully-formed terrestrial planets if the instabilities occur late, and also destroy the icy planetesimal population. Stable or weakly unstable systems allow terrestrial planets to accrete in their inner regions and significant dust to be produced in their outer regions, detectable at mid-infrared wavelengths as debris disks. Stars older than ~100 Myr with bright cold dust emission (in particular at ? ~ 70 ?m) signpost dynamically calm environments that were conducive to efficient terrestrial accretion. Such emission is present around ~16% of billion-year old Solar-type stars. Our simulations yield numerous secondary results: 1) the typical eccentricities of as-yet undetected terrestrial planets are ~0.1 but there exists a novel class of terrestrial planet system whose single planet undergoes large amplitude oscillations in orbital eccentricity and inclination; 2) by scaling our systems to match the observed semimajor axis distribution of giant exoplanets, we predict that terrestrial exoplanets in the same systems should be a few times more abundant at ~0.5 AU than giant or terrestrial exoplanets at 1 AU; 3) the Solar System appears to be unusual in terms of its combination of a rich terrestrial planet system and a low dust content. This may be explained by the weak, outward-directed instability that is thought to have caused the late heavy bombardment. The movie associated to Fig. 2 is available in electronic form at http://www.aanda.org

  19. ExTrA

    NASA Astrophysics Data System (ADS)

    Bonfils, X.; Almenara, J.-M.; ExTrA Team

    2014-04-01

    ExTrA is an ERC-funded project offering a novel method to dramatically improve on the precision of ground based photometry and more efficiently search for exo-Earths orbiting cool stars. The method makes use of a multi-object spectrograph to add the spectroscopic resolution to the traditional differential photometry method. We will discuss how this shall enable the fine correction of color-dependent systematics (atmospheric variations, instrument and detector errors) that would otherwise hinder ground-based observations. ExTrA aims to develop this method with a new facility composed of small telescopes (60cm in diameter) and a near-infrared spectrograph (R<500, lbda=0.8-1.6?m). Near-infrared observations will boost the efficiency of its cool-star observations, such that ExTrA might become the most sensitive survey for Earthsize planets transiting nearby planets. It shall yield dozens exo-Earths amenable to atmospheric characterization, including several habitable exo-Earths, which may provide our first peek into an exolife laboratory. In this talk, we shall discuss all aspects of ExTrA from its initial concept to the expected exoplanet yield, passing by its design and implementation.

  20. TERRESTRIAL ECOTOXICOLOGY

    EPA Science Inventory

    Terrestrial ecotoxicology is the study of how environmental pollutants affect land-dependent organisms and their environment. It requires three elements: (1) a source, (2) a receptor, and (3) an exposure pathway. This article reviews the basic principles of each of each element...

  1. Raman spectroscopic studies of carbon in extra-terrestrial materials

    NASA Astrophysics Data System (ADS)

    Macklin, John; Brownlee, Donald; Chang, Sherwood; Bunch, Ted

    1990-04-01

    The measurements obtained here indicate ways in which micro-Raman spectroscopy can be used to elucidate structural characteristics and distribution of carbon in meteorites and interplanetary dust particles (IDPs). Existing information about structurally significant aspects of Raman measurements of graphite is combined with structurally relevant findings from the present micro-Raman studies of carbons prepared by carbonization of polyvinylidine chloride (PVDC) at various temperatures and natural material, as well as several acid residues from the Allende and Murchison meteorites in order to establish new spectra-structure relationships. Structural features of many of the materials in this study have been measured by x ray analysis and electron microscopy: thus, their structural differences can be directly correlated with differences in the Raman spectra. The spectral parameters consequently affirmed as indicators of structure are used as a measure of structure in materials that have unknown carbon structure, especially IDPs. The unique applicability of micro-Raman spectroscopy is realized not only in the ability to conveniently measure spectra of micron-size IDPs, but also micro-sized parts of an inhomogeneous material. Microcrystalline graphite is known to give Raman spectra that differ dependent on crystallite size (see e.g., Lespade, et. al., 1984, or Nemanich and Solin, 1979). The spectral changes that accompany decreasing particle size include increase in the ratio (R) of the intensity of the band near 1350 cm(-1) (D band) to that of the band near 1600 cm(-1) (G band) increase in the half width of the D band (wD) increase in the frequency maximum of the G band and increase in the half-width (wG) of the 2nd order band near 2700 cm(-1) (G) band.

  2. Raman spectroscopic studies of carbon in extra-terrestrial materials

    NASA Technical Reports Server (NTRS)

    Macklin, John; Brownlee, Donald; Chang, Sherwood; Bunch, Ted

    1990-01-01

    The measurements obtained here indicate ways in which micro-Raman spectroscopy can be used to elucidate structural characteristics and distribution of carbon in meteorites and interplanetary dust particles (IDPs). Existing information about structurally significant aspects of Raman measurements of graphite is combined with structurally relevant findings from the present micro-Raman studies of carbons prepared by carbonization of polyvinylidine chloride (PVDC) at various temperatures and natural material, as well as several acid residues from the Allende and Murchison meteorites in order to establish new spectra-structure relationships. Structural features of many of the materials in this study have been measured by x ray analysis and electron microscopy: thus, their structural differences can be directly correlated with differences in the Raman spectra. The spectral parameters consequently affirmed as indicators of structure are used as a measure of structure in materials that have unknown carbon structure, especially IDPs. The unique applicability of micro-Raman spectroscopy is realized not only in the ability to conveniently measure spectra of micron-size IDPs, but also micro-sized parts of an inhomogeneous material. Microcrystalline graphite is known to give Raman spectra that differ dependent on crystallite size (see e.g., Lespade, et. al., 1984, or Nemanich and Solin, 1979). The spectral changes that accompany decreasing particle size include increase in the ratio (R) of the intensity of the band near 1350 cm(-1) (D band) to that of the band near 1600 cm(-1) (G band) increase in the half width of the D band (wD) increase in the frequency maximum of the G band and increase in the half-width (wG) of the 2nd order band near 2700 cm(-1) (G) band.

  3. Reducing Extra-Terrestrial Excavation Forces with Percussion

    NASA Technical Reports Server (NTRS)

    Mueller, Robert; Schuler, Jason M.; Smith, Jonathan Drew; Nick, Andrew J.; Lippitt, Thomas

    2012-01-01

    High launch costs and mission requirements drive the need for low mass excavators with mobility platforms, which in turn have little traction and excavation reaction capacity in low gravity environments. This presents the need for precursor and long term future missions with low mass robotic mining technology to perform In-Situ Resource Utilization (ISRU) tasks. This paper discusses a series of experiments that investigate the effectiveness of a percussive digging device to reduce excavation loads and thereby the mass of the excavator itself. A percussive mechanism and 30" wide pivoting bucket were attached at the end of the arm simulating a basic backhoe with a percussion direction tangent to the direction of movement. Impact energies from 13.6J to 30.5J and frequencies from 0 BPM to 700 BPM were investigated. A reduction in excavation force of as much as 50% was achieved in this experimental investigation.

  4. Satellite Radiotomography of Ionospheric Responces to Extra-Terrestrial Forcing

    NASA Astrophysics Data System (ADS)

    Kunitsyn, Viacheslav; Padokhin, Artem; Andreeva, Elena; Tereshchenko, Evgeny; Nesterov, Ivan; Vorontsov, Artem

    Our work addresses the study of the response of the atmosphere and ionosphere to a variety of external forcing such as solar flares and particle precipitation. Particle precipitation plays important role in the system of magnetosphere-ionosphere- atmosphere coupling during geomagnetic storms. Using radio tomographic imaging of the ionosphere based on navigational satellite systems (Parus/Transit and GPS/GLONASS) we present and discuss the examples illustrating ionospheric effects caused by particle precipitations detected by DMSP satellites. It is shown that the spatial structure of corpuscular ionization in the tomographic images is qualitatively close to latitudinal distribution of the precipitating particles. The distributions of ionospheric plasma observed during strong geomagnetic disturbances and particle precipitations have multiple extrema and wave-like structures with a spatial scale ranging from a few dozens to a few hundreds of kilometers; the characteristic sizes of latitudinal variations in the corresponding corpuscular flows widely vary from a few degrees to a few dozens degrees latitude. The obtained experimental results are in good agreement with the results of the numeric modelling of the AGW generation by volumetric sources. We also present the comparison of the effects of ionization of the ionosphere by a series of intense X-class solar flares during the 23rd and 24th solar cycles based on the data of satellite navigation and augumentation systems (GPS/GLONASS and SBAS). The analysis shows that the intensity of the ionospheric effects estimated from the variations in total electron content is barely related to the intensity of the X-ray flare for the X-class events. The amplitude of variations in the ionization of the upper atmosphere is mainly controlled by the intensity of variations in solar EUV radiation, which is not always correlated to the X-Ray radiation during flares. The authors acknowledge the support of the Russian Foundation for Basic Research (grants ? 13-05-01122, 14-05-31445, 14-05-00855, 14-05-10069), grants of the President of Russian Federation (MK-2670.2014.5) and Lomonosov Moscow State University Program of Development.

  5. Astronomers Reveal Extinct Extra-Terrestrial Fusion Reactor

    NASA Astrophysics Data System (ADS)

    2004-06-01

    An international team of astronomers, studying the left-over remnants of stars like our own Sun, have found a remarkable object where the nuclear reactor that once powered it has only just shut down. This star, the hottest known white dwarf, H1504+65, seems to have been stripped of its entire outer regions during its death throes leaving behind the core that formed its power plant. Scientists from the United Kingdom, Germany and the USA focused two of NASA's space telescopes, the Chandra X-ray Observatory and the Far Ultraviolet Spectroscopic Explorer (FUSE), onto H1504+65 to probe its composition and measure its temperature. The data revealed that the stellar surface is extremely hot, 200,000 degrees, and is virtually free of hydrogen and helium, something never before observed in any star. Instead, the surface is composed mainly of carbon and oxygen, the 'ashes' of the fusion of helium in a nuclear reactor. An important question we must answer is why has this unique star lost the hydrogen and helium, which usually hide the stellar interior from our view? Professor Martin Barstow (University of Leicester) said. 'Studying the nature of the ashes of dead stars give us important clues as to how stars like the Sun live their lives and eventually die. The nuclear waste of carbon and oxygen produced in the process are essential elements for life and are eventually recycled into interstellar space to form new stars, planets and, possibly, living beings.' Professor Klaus Werner (University of Tbingen) said. 'We realized that this star has, on astronomical time scales, only very recently shut down nuclear fusion (about a hundred years ago). We clearly see the bare, now extinct reactor that once powered a bright giant star.' Dr Jeffrey Kruk (Johns Hopkins University) said: 'Astronomers have long predicted that many stars would have carbon-oxygen cores near the end of their lives, but I never expected we would actually be able to see one. This is a wonderful opportunity to improve our understanding of the life-cycle of stars.' The Chandra X-ray data also reveal the signatures of neon, an expected by-product of helium fusion. However, a big surprise was the presence of magnesium in similar quantities. This result may provide a key to the unique composition of H1504+65 and validate theoretical predictions that, if massive enough, some stars can extend their lives by tapping yet another energy source: the fusion of carbon into magnesium. However, as magnesium can also be produced by helium fusion, proof of the theory is not yet ironclad. The final link in the puzzle would be the detection of sodium, which will require data from yet another observatory: the Hubble Space Telescope. The team has already been awarded time on the Hubble Space Telescope to search for sodium in H1504+65 next year, and will, hopefully, discover the final answer as to the origin of this unique star. This work will be published in July in the 'Astronomy & Astrophysics' journal. The Chandra X-ray Observatory and the Far Ultraviolet Spectroscopic Explorer (FUSE) were both launched into orbit by NASA in 1999. Their instruments make use of a technique called spectroscopy, which spreads the light obtained from astronomical objects into its constituent X-ray and ultraviolet 'colours', in the same way visible light is dispersed into a rainbow naturally, by water droplets in the atmosphere, or artificially, by a prism. When studied in fine detail each spectrum is a unique 'fingerprint' which tells us what elements are present and reveals the physical conditions in the object being studied. Related Internet Address http://www.ras.org.uk/index.php?option=com_content&task=view&id=673&Itemid=2

  6. Problem of searching for extra-terrestrial civilizations

    NASA Technical Reports Server (NTRS)

    Ambartsumyan, V. A.

    1974-01-01

    Possible criteria characterizing extraterrestrial civilizations and their detection are: (1) deduction of their existence by evaluating astronomical prerequisites for the development of life in remote planetary systems; (2) detection and communication with extraterrestrial civilizations; and (3) the problem of language and content of information in transmitted signals.

  7. A SETI experiment. [Search for Extra Terrestrial Intelligence

    NASA Technical Reports Server (NTRS)

    Mclaughlin, W. I.

    1986-01-01

    In order to increase the probability of contact in the search for extraterrestrial intelligence (SETI), it has been proposed to search more intensively in certain regions of the electromagnetic spectrum ('the water hole'). The present paper describes a similar narrowing of the search in the time domain. Application of this strategy results in the SETI experiments searching for signals from the Tau Ceti system late in 1986 and early in 1987, and from the Epsilon Eridani system in mid 1988.

  8. Extra-terrestrial Life in the Milky Way Galaxy?

    NASA Astrophysics Data System (ADS)

    Evans, Neal J.

    2014-09-01

    Are we alone? Along with questions about black holes, this is one of the questions most commonly asked of astrophysicists. While the simple answer is that we don't know, logical and rational exploration of the question can be illuminating and a very good way to introduce non-scientists to the "scientific worldview." This short essay is based on a class for students not majoring in science, which I have taught for nearly forty years at the University of Texas at Austin.

  9. Phenomenology of Extra Dimensions

    SciTech Connect

    Hewett, J.L.; /SLAC

    2006-11-07

    If the structure of spacetime is different than that readily observed, gravitational physics, particle physics and cosmology are all immediately affected. The physics of extra dimensions offers new insights and solutions to fundamental questions arising in these fields. Novel ideas and frameworks are continuously born and evolved. They make use of string theoretical features and tools and they may reveal if and how the 11-dimensional string theory is relevant to our four-dimensional world. We have outlined some of the experimental observations in particle and gravitational physics as well as astrophysical and cosmological considerations that can constrain or confirm these scenarios. These developing ideas and the wide interdisciplinary experimental program that is charted out to investigate them mark a renewed effort to describe the dynamics behind spacetime. We look forward to the discovery of a higher dimensional spacetime.

  10. Extra-Articular Endoscopy.

    PubMed

    Doral, Mahmut N; Huri, Gazi; Bohacek, Ivan; Turhan, Egemen; Bojanic, Ivan

    2016-03-01

    With the advent of endoscopy in the last 2 decades, a number of procedures, and modifications to them, have been developed and have advanced exponentially. The list of indications was extended over time because of several reasons: better understanding of the pathophysiology, better diagnostics, and advances in endoscopic technology. In this review article, we summarize the most frequently performed extra-articular endoscopic procedures on the extremities. As there are several methods, some have been described briefly, whereas others have been described in greater detail, such as suprascapular nerve entrapment syndrome and Achilles tendon disorders, as they present our area of interest and subspecialty domain. Recent advances in the treatment of versatile pathologic entities have been described, together with new methods, which currently lack sufficient clinical data but still represent promising techniques for the future. PMID:26752776

  11. Terrestrial Planet Finder Coronagraph Observatory summary

    NASA Technical Reports Server (NTRS)

    Ford, Virginia; Levine-Westa, Marie; Kissila, Andy; Kwacka, Eug; Hoa, Tim; Dumonta, Phil; Lismana, Doug; Fehera, Peter; Cafferty, Terry

    2005-01-01

    Creating an optical space telescope observatory capable of detecting and characterizing light from extra-solar terrestrial planets poses technical challenges related to extreme wavefront stability. The Terrestrial Planet Finder Coronagraph design team has been developing an observatory based on trade studies, modeling and analysis that has guided us towards design choices to enable this challenging mission. This paper will describe the current flight baseline design of the observatory and the trade studies that have been performed. The modeling and analysis of this design will be described including predicted performance and the tasks yet to be done.

  12. Measurements of H2O in the terrestrial mesosphere and implications for extra-terrestrial sources

    NASA Technical Reports Server (NTRS)

    Olivero, John J.

    1988-01-01

    Recent measurements of mesospheric water vapor and their implications for the existence of extraterrestrial sources of water are discussed. This study was prompted by the work of L. Frank and others who, based on their interpretation of transient dark spots visible in ultraviolet images of the Earth's dayglow emission, have proposed that a large flux of small comets enters the Earth's upper atmosphere each day. To date, however, analysis does not conclusively refute or support the idea of an external source.

  13. A theoretical investigation of isotopic anomalies of xenon in terrestrial and extra-terrestrial samples

    NASA Technical Reports Server (NTRS)

    Sabu, D. D.

    1977-01-01

    The abundance and isotopic composition of noble gases in meteorites is discussed in relation to the composition of the early solar system. Carbonaceous chondrites contain a unique Xenon-X, which is rich in heavy and light isotopes. Variations in the occurrence of type-X and type-Y (the normal component) noble gases are of such magnitude that neither the injection of material from a nearby supernova nor presence of presolar grains can account for the anomalies in meteorites. Therefore, it is suggested that the entire solar system may have condensed from the debris of a single local supernova.

  14. The terrestrial impact cratering record.

    NASA Astrophysics Data System (ADS)

    Grieve, R. A. F.; Pesonen, L. J.

    1992-12-01

    Approximately 130 terrestrial hypervelocity impact craters are currently known. The rate of discovery of new craters is 3 - 5 craters per year. Although modified by erosion, terrestrial impact craters exhibit the range of morphologies observed for craters on other terrestrial planetary bodies. Due to erosion and its effects on form, terrestrial craters are recognized primarily by the occurrence of shock metamorphic effects. Terrestrial craters have a set of geophysical characteristics which are largely the result of the passage of a shock wave and impact-induced fracturing. Much current work is focused on the effects of impact on Earth evolution. Previous work on shock metamorphism and the contamination of impact melt rocks by meteoritic siderophile elements provides a basis for the interpretation of the physical and chemical evidence from Cretaceous-Tertiary boundary sites as resulting from a major impact. By analogy with the lunar record and modelling of the effects of very large impacts, it has been proposed that biological and atmospheric evolution of the Earth could not stabilize before the end of the late heavy bombardment ?3.8 Ga ago. The present terrestrial cratering rate is 5.42.710-15 km-2a-1 for a diameter ?20 km. On a gobal scale, a major impact sufficient to cripple human civilization severely will occur on time scales of ?106a.

  15. Extra large telescope actuator

    NASA Astrophysics Data System (ADS)

    Nalbandian, Ruben; Hatheway, Alson E.

    2003-02-01

    The goal of the Extra Large Telescope Actuator (ELTA) development project was to demonstrate operation of a relatively high stiffness, single stage optical positioning actuator capable of achieving diffraction-limited performance (<10 nm) in the visible optical band for weeks at a time while consuming no electrical power and dissipating no heat. The design challenge was to develop a linear positioning mechanism exhibiting high stiffness, low power, zero backlash, and thermal stability over extended time periods. The key to achieving high resolution, and stability with low power is to eliminate the closed-loop control system that is normally employed to overcome the nonlinearities and hysteresis inherent in some technologies, such as piezoelectric and magnetostrictive transducers. This was accomplished by using the patented elastic transducer developed by Alson E. Hatheway (AEH Inc.) This device consists of two elastic elements; a soft spring and a stiff flexural member. Deflection of the soft spring applies a force input to the stiff flexure, which responds with a proportionally reduced output deflection. To maintain linearity, the displacements, and hence the stresses, developed in both elastic members are kept below the micro-yield strength of the material. The AEH transducer is inherently linear and hysteresis free. The unique design features of this actuator which contribute to its extremely precise motion capability include an electric motor driving a leadscrew through a zero backlash harmonic drive gear reduction. The already fine incremental motion of the leadscrew nut is further attenuated by the elastic action of the AEH transducer, to provide output motion with resolution <10 nm.

  16. The range of validity of the two-body approximation in models of terrestrial planet accumulation. II - Gravitational cross sections and runaway accretion

    NASA Technical Reports Server (NTRS)

    Wetherill, G. W.; Cox, L. P.

    1985-01-01

    The validity of the two-body approximation in calculating encounters between planetesimals has been evaluated as a function of the ratio of unperturbed planetesimal velocity (with respect to a circular orbit) to mutual escape velocity when their surfaces are in contact (V/V-sub-e). Impact rates as a function of this ratio are calculated to within about 20 percent by numerical integration of the equations of motion. It is found that when the ratio is greater than 0.4 the two-body approximation is a good one. Consequences of reducing the ratio to less than 0.02 are examined. Factors leading to an optimal size for growth of planetesimals from a swarm of given eccentricity and placing a limit on the extent of runaway accretion are derived.

  17. Accretion and differentiation of the terrestrial planets with implications for the compositions of early-formed Solar System bodies and accretion of water

    NASA Astrophysics Data System (ADS)

    Rubie, D. C.; Jacobson, S. A.; Morbidelli, A.; O'Brien, D. P.; Young, E. D.; de Vries, J.; Nimmo, F.; Palme, H.; Frost, D. J.

    2015-03-01

    In order to test accretion simulations as well as planetary differentiation scenarios, we have integrated a multistage core-mantle differentiation model with N-body accretion simulations. Impacts between embryos and planetesimals are considered to result in magma ocean formation and episodes of core formation. The core formation model combines rigorous chemical mass balance with metal-silicate element partitioning data and requires that the bulk compositions of all starting embryos and planetesimals are defined as a function of their heliocentric distances of origin. To do this, we assume that non-volatile elements are present in Solar System (CI) relative abundances in all bodies and that oxygen and H2O contents are the main compositional variables. The primary constraint on the combined model is the composition of the Earth's primitive mantle. In addition, we aim to reproduce the composition of the martian mantle and the mass fractions of the metallic cores of Earth and Mars. The model is refined by least squares minimization with up to five fitting parameters that consist of the metal-silicate equilibration pressure and 1-4 parameters that define the starting compositions of primitive bodies. This integrated model has been applied to six Grand Tack N-body accretion simulations. Investigations of a broad parameter space indicate that: (1) accretion of Earth was heterogeneous, (2) metal-silicate equilibration pressures increase as accretion progresses and are, on average, 60-70% of core-mantle boundary pressures at the time of each impact, and (3) a large fraction (70-100%) of the metal of impactor cores equilibrates with a small fraction of the silicate mantles of proto-planets during each core formation event. Results are highly sensitive to the compositional model for the primitive starting bodies and several accretion/core-formation models can thus be excluded. Acceptable fits to the Earth's mantle composition are obtained only when bodies that originated close to the Sun, at <0.9-1.2 AU, are highly reduced and those from beyond this distance are increasingly oxidized. Reasonable concentrations of H2O in Earth's mantle are obtained when bodies originating from beyond 6-7 AU contain 20 wt% water ice (icy bodies that originated between the snow line and this distance did not contribute to Earth's accretion because they were swept up by Jupiter and Saturn). In the six models examined, water is added to the Earth mainly after 60-80% of its final mass has accreted. The compositional evolution of the mantles of Venus and Mars are also constrained by the model. The FeO content of the martian mantle depends critically on the heliocentric distance at which the Mars-forming embryo originated. Finally, the Earth's core is predicted to contain 8-9 wt% silicon, 2-4 wt% oxygen and 10-60 ppm hydrogen, whereas the martian core is predicted to contain low concentrations (<1 wt%) of Si and O.

  18. Phenomenology of universal extra dimensions

    SciTech Connect

    Kong, Kyoungchul; Matchev, Konstantin T.; /Florida U.

    2006-10-01

    In this proceeding, the phenomenology of Universal Extra Dimensions (UED), in which all the Standard Model fields propagate, is explored. We focus on models with one universal extra dimension, compactified on an S{sub 1}/Z{sub 2} orbifold. We revisit calculations of Kaluza-Klein (KK) dark matter without an assumption of the KK mass degeneracy including all possible coannihilations. We then contrast the experimental signatures of low energy supersymmetry and UED.

  19. A numerical treatment of melt/solid segregation - Size of the eucrite parent body and stability of the terrestrial low-velocity zone

    NASA Technical Reports Server (NTRS)

    Walker, D.; Stolper, E. M.; Hays, J. F.

    1978-01-01

    Crystal sinking to form cumulates and melt percolation toward segregation in magma pools can be treated with modifications of Stokes' and Darcy's laws, respectively. The velocity of crystals and melt depends, among other things, on the force of gravity (g) driving the separations and the cooling time of the environment. The increase of g promotes more efficient differentiation, whereas the increase of cooling rate limits the extent to which crystals and liquid can separate. The rate at which separation occurs is strongly dependent on the proportion of liquid that is present. The observation of cumulates and segregated melts among the eucrite meteorites is used as a basis for calculating the g (and planet size) required to perform these differentiations. The eucrite parent body was probably at least 10-100 km in radius. The earth's low velocity zone (LVZ) is shown to be unstable with respect to draining itself of excess melt if the melt forms an interconnecting network. A geologically persistent LVZ with a homogeneous distribution of melt can be maintained with melt fractions only on the order of 0.1% or less.

  20. Sex differences in gait utilization and energy metabolism during terrestrial locomotion in two varieties of chicken (Gallus gallus domesticus) selected for different body size

    PubMed Central

    Rose, Kayleigh A.; Nudds, Robert L.; Butler, Patrick J.; Codd, Jonathan R.

    2015-01-01

    ABSTRACT In leghorn chickens (Gallus gallus domesticus) of standard breed (large) and bantam (small) varieties, artificial selection has led to females being permanently gravid and sexual selection has led to male-biased size dimorphism. Using respirometry, videography and morphological measurements, sex and variety differences in metabolic cost of locomotion, gait utilisation and maximum sustainable speed (Umax) were investigated during treadmill locomotion. Males were capable of greater Umax than females and used a grounded running gait at high speeds, which was only observed in a few bantam females and no standard breed females. Body mass accounted for variation in the incremental increase in metabolic power with speed between the varieties, but not the sexes. For the first time in an avian species, a greater mass-specific incremental cost of locomotion, and minimum measured cost of transport (CoTmin) were found in males than in females. Furthermore, in both varieties, the female CoTmin was lower than predicted from interspecific allometry. Even when compared at equivalent speeds (using Froude number), CoT decreased more rapidly in females than in males. These trends were common to both varieties despite a more upright limb in females than in males in the standard breed, and a lack of dimorphism in posture in the bantam variety. Females may possess compensatory adaptations for metabolic efficiency during gravidity (e.g. in muscle specialization/posture/kinematics). Furthermore, the elevated power at faster speeds in males may be linked to their muscle properties being suited to inter-male aggressive combat. PMID:26405047

  1. Extra Stimulation in Intermediate Grade Reading.

    ERIC Educational Resources Information Center

    Mason, George E.

    Three types of extra stimulation in reading are discussed: extra teacher time devoted to teaching reading, extra student time devoted to practice in reading, and extra motivation and reinforcement leading to greater amounts of student reading outside the school. Problems are created (1) when teaching time spent on reading is increased in the

  2. Scientific Visualization of Extra Dimensions

    NASA Astrophysics Data System (ADS)

    Black, Don V.

    2010-10-01

    In the 21st Century, many theoretical physicists claim that higher dimensions may indeed exist. Arkani-Hamed, Dimopoulos, & Dvali (ADD) and Randall-Sundrum (RS), in addition to Kaluza-Klein (KK) and M-string theorists, have introduced reasonable explanations for the existence of heretofore ``invisible'' higher dimensions. Whether or not these extra dimensions actually exist is irrelevant to their contributions to the visionary conceptualization associated with novel and improved mathematical and physical analysis. Envisioning extra dimensions beyond the three of common experience is a daunting challenge for three dimensional observers. Intuition relies on experience gained in a three dimensional environment. Gaining experience with virtual four dimensional objects and virtual three manifolds in four-space on a personal computer may provide the basis for an intuitive grasp of four dimensions. This presentation is a video ``outtake'' of the author's research into ``Visualizing Extra Spatial Dimensions'' at the University of California at Irvine.

  3. Collider searches for extra dimensions

    SciTech Connect

    Landsberg, Greg; /Brown U.

    2004-12-01

    Searches for extra spatial dimensions remain among the most popular new directions in our quest for physics beyond the Standard Model. High-energy collider experiments of the current decade should be able to find an ultimate answer to the question of their existence in a variety of models. Until the start of the LHC in a few years, the Tevatron will remain the key player in this quest. In this paper, we review the most recent results from the Tevatron on searches for large, TeV{sup -1}-size, and Randall-Sundrum extra spatial dimensions, which have reached a new level of sensitivity and currently probe the parameter space beyond the existing constraints. While no evidence for the existence of extra dimensions has been found so far, an exciting discovery might be just steps away.

  4. Provenance of the terrestrial planets.

    PubMed

    Wetherill, G W

    1994-01-01

    Earlier work on the simultaneous accumulation of the asteroid belt and the terrestrial planets is extended to investigate the relative contribution to the final planets made by material from different heliocentric distances. As before, stochastic variations intrinsic to the accumulation processes lead to a variety of final planetary configurations, but include systems having a number of features similar to our solar system. Fifty-nine new simulations are presented, from which thirteen are selected as more similar to our solar system than the others. It is found that the concept of "local feeding zones" for each final terrestrial planet has no validity for this model. Instead, the final terrestrial planets receive major contributions from bodies ranging from 0.5 to at least 2.5 AU, and often to greater distances. Nevertheless, there is a correlation between the final heliocentric distance of a planet and its average provenance. Together with the effect of stochastic fluctuations, this permits variation in the composition of the terrestrial planets, such as the difference in the decompressed density of Earth and Mars. Biologically important light elements, derived from the asteroidal region, are likely to have been significant constituents of the Earth during its formation. PMID:11539576

  5. Origin of the 'Extra Entropy'

    NASA Technical Reports Server (NTRS)

    Mushotzky, R.

    2008-01-01

    I will discuss how one can determine the origin of the 'extra entropy' in groups and clusters and the feedback needed in models of galaxy formation. I will stress the use of x-ray spectroscopy and imaging and the critical value that Con-X has in this regard.

  6. Collider Phenomenology of Extra Dimensions

    SciTech Connect

    Lillie, Benjamin Huntington; /Stanford U., Phys. Dept. /SLAC

    2006-03-10

    In recent years there has been much interest in the possibility that there exist more spacetime dimensions than the usual four. Models of particle physics beyond the Standard Model that incorporate these extra dimensions can solve the gauge hierarchy problem and explain why the fermion masses a spread over many orders of magnitude. In this thesis we explore several possibilities for models with extra dimensions. First we examine constraints on the proposal of Arkani-Hamed and Schmaltz that the Standard Model fermions are localized to different positions in an extra dimension, thereby generating the hierarchy in fermion masses. We find strong constraints on the compactification scale of such models arising from flavor-changing neutral currents. Next we investigate the phenomenology of the Randall-Sundrum model, where the hierarchy between the electroweak and Planck scales is generated by the warping in a five-dimensional anti-de Sitter space. In particular, we investigate the ''Higgsless'' model of electroweak symmetry breaking due to Csaki et. al., where the Higgs has been decoupled from the spectrum by taking its vacuum expectation value to infinity. We find that this model produces many distinctive features at the LHC. However, we also find that it is strongly constrained by precision electroweak observables and the requirement that gauge-boson scattering be perturbative. We then examine the model with a finite vacuum expectation value, and find that there are observable shifts to the Higgs scalar properties. Finally, in the original large extra dimension scenario of Arkani-Hamed, Dimopoulos, and Dvali, the hierarchy problem is solved by allowing gravity to propagate in a large extra dimensional volume, while the Standard Model fields are confined to 4 dimensions. We consider the case where there are a large number of extra dimensions (n {approx} 20). This model can solve the hierarchy problem without introducing a exponentially large radii for the extra dimensions, and represents a scenario that is difficult to obtain in string theory. We show that, if this scenario holds, the number of dimensions can be constrained to be larger than the number predicted by critical string theory. Searching for signals of many dimensions is then an important test of whether string theory is a good description of quantum gravity.

  7. Late Stage Accretion of the Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Agnor, C.; Canup, R. M.; Levison, H. F.

    1998-09-01

    We have performed direct N-body integrations of the final stages of terrestrial planet formation, following the evolution of 50 initial bodies for approximately 200 million years. We utilize a newly developed algorithm, "SYMBA" (Duncan et al. 1998, in press), which is capable of handling close encounters in a completely symplectic manner. Our starting conditions are motivated by recent results of mid-stage accretion simulations (Weidenshilling et al. 1997), which show that most of the mass in the terrestrial region is contained in the largest few tens of bodies after approximately a million years. In particular, our study has been directed towards the analysis of the type and frequency of giant impact events that occur during the final stage of terrestrial planet formation.

  8. Formation of the terrestrial planets

    NASA Technical Reports Server (NTRS)

    Wetherill, G. W.

    1980-01-01

    Two growth mechanisms are identified for the development of the terrestrial planets: (1) gravitational instability leading to a collapse, and (2) gravitational accumulation caused by two-body collisions and coherence. The presence of a dynamically-significant gas phase would not affect either mechanism. Theoretical expressions are presented for the production of giant gaseous protoplanets by gravitational instability within a central dust layer. Gravitational accumulation is discussed with reference to the accumulation of planetesimals from a gas-free circumsolar swarm of bodies. Numerical simulations are given for the early stages of accumulation. The Safronov steady-state velocity is considered, noting that the competition between mutual collisional damping and gravitational acceleration by the members of a solar swarm yields a steady-state velocity distribution where the mean velocity is comparable to the escape velocity of the largest body. A time scale for accumulation is postulated on the basis of the radial distribution of a swarm of non-accreting bodies of equal size. The simultaneous gas-free accumulation of several terrestrial planets is noted. Attention is also given to growth mechanisms in gas-rich interplanetary media.

  9. Tidally Heated Terrestrial Exoplanets

    NASA Astrophysics Data System (ADS)

    Henning, Wade Garrett

    This work models the surface and internal temperatures for hypothetical terrestrial planets in situations involving extreme tidal heating. The feasibility of such planets is evaluated in terms of the orbital perturbations that may give rise to them, their required proximity to a hoststar, and the potential for the input tidal heating to cause significant partial melting of the mantle. Trapping terrestrial planets into 2:1 resonances with migrating Hot Jupiters is considered as a reasonable way for Earth-like worlds to both maintain high eccentricities and to move to short enough orbital periods (1-20 days) for extreme tidal heating to occur. Secular resonance and secular orbital perturbations may support moderate tidal heating at a low equilibrium eccentricity. At orbital periods below 10-30 days, with eccentricities from 0.01 to 0.1, tidal heat may greatly exceed radiogenic heat production. It is unlikely to exceed insolation, except when orbiting very low luminosity hosts, and thus will have limited surface temperature expression. Observations of such bodies many not be able to detect tidal surface enhancements given a few percent uncertainty in albedo, except on the nightside of spin synchronous airless objects. Otherwise detection may occur via spectral detection of hotspots or high volcanic gas concentrations including sulfur dioxide and hydrogen sulfide. The most extreme cases may be able to produce magma oceans, or magma slush mantles with up to 40-60% melt fractions. Tides may alter the habitable zones for smaller red dwarf stars, but are generally detrimental. Multiple viscoelastic models, including the Maxwell, Voigt-Kelvin, Standard Anelastic Solid, and Burgers rheologies are explored and applied to objects such as Io and the super-Earth planet GJ 876d. The complex valued Love number for the Burgers rheology is derived and found to be a useful improvement when modeling the low temperature behavior of tidal bodies, particularly during low eccentricity excursions. Viscoelastic solutions for GJ 876d are typical of extreme short period high eccentricity objects with tidal-convectiveequilibrium heat rates between 10,000 to 500,000 terawatts.

  10. Continuously recording body temperature in terrestrial chelonians

    USGS Publications Warehouse

    Nussear, K.E.; Esque, T.C.; Tracy, C.R.

    2002-01-01

    The degree of interaction between mercury and cholinesterase inhibiting pesticides was determined by comparing enzyme responses to sublethal dosages of parathion or carbofuran in quail fed 0.05, 0.5, or 5.0 ppm morsodren for 18 weeks. A statistically significant interaction was defined as greater brain cholinesterase inhibition in morsodren-fed than in clean-fed birds following pesticide dosage. The tissue residues of mercury that accumulated before significant mercury-parathion interactions occurred were higher than levels that might be expected in natural populations, but significant mercury-carbofuran interactions occurred in birds that had only accumulated 1.0 ppm liver mercury. The results indicate that indiscriminate usage of cholinesterase inhibiting pesticides are dangerous, since natural populations of fish-eating birds oftentimes contain this magnitude of mercury.

  11. Extra-articular Synovial Chondromatosis Eroding and Penetrating the Acromion

    PubMed Central

    El Rassi, George; Matta, Jihad; Hijjawi, Ayman; Khair, Ousama Abou; Fahs, Sara

    2015-01-01

    Synovial chondromatosis of the shoulder is an uncommon disorder. It usually affects the glenohumeral joint and is characterized by metaplasia of the synovium leading to the formation of osteochondral loose bodies. Few cases of extra-articular subacromial synovial chondromatosis involving the rotator cuff tendon have been reported in the literature. The treatment of previously reported cases consisted of open bursectomy and removal of loose bodies. We report a case of subacromial synovial chondromatosis without rotator cuff involvement but with severe erosion and fracture of the acromion. Treatment consisted of shoulder arthroscopy to remove all loose bodies, total bursectomy, and debridement of the acromion. Potential benefits of arthroscopy were also evaluated. PMID:26697302

  12. Extra-articular Synovial Chondromatosis Eroding and Penetrating the Acromion.

    PubMed

    El Rassi, George; Matta, Jihad; Hijjawi, Ayman; Khair, Ousama Abou; Fahs, Sara

    2015-10-01

    Synovial chondromatosis of the shoulder is an uncommon disorder. It usually affects the glenohumeral joint and is characterized by metaplasia of the synovium leading to the formation of osteochondral loose bodies. Few cases of extra-articular subacromial synovial chondromatosis involving the rotator cuff tendon have been reported in the literature. The treatment of previously reported cases consisted of open bursectomy and removal of loose bodies. We report a case of subacromial synovial chondromatosis without rotator cuff involvement but with severe erosion and fracture of the acromion. Treatment consisted of shoulder arthroscopy to remove all loose bodies, total bursectomy, and debridement of the acromion. Potential benefits of arthroscopy were also evaluated. PMID:26697302

  13. Warping the universal extra dimensions

    NASA Astrophysics Data System (ADS)

    McDonald, Kristian L.

    2009-07-01

    We develop the necessary ingredients for the construction of realistic models with warped universal extra dimensions. Our investigations are based on the seven-dimensional (7D) spacetime AdS5T2/Z2 and we derive the Kaluza-Klein (KK) spectra for gravitons, bulk vectors, and the TeV brane localized Higgs boson. We show that, starting with a massive 7D fermion, one may obtain a single chiral massless mode whose profile is readily localized towards the Planck or TeV brane. This allows one to place the standard model fermions in the bulk and construct models of flavor as in Randall-Sundrum models. Our solution also admits the familiar KK parity of models with universal extra dimensions so that the lightest odd KK state is stable and may be a dark matter candidate. As an additional feature the AdS5 warping ensures that the excited modes on the torus, including the dark matter candidate, appear at TeV energies (as is usually assumed in models with universal extra dimensions) even though the Planck scale sets the dimensions for the torus.

  14. Screening and validation of EXTraS data products

    NASA Astrophysics Data System (ADS)

    Carpano, Stefania; Haberl, F.; De Luca, A.; Tiengo, A.: Israel, G.; Rodriguez, G.; Belfiore, A.; Rosen, S.; Read, A.; Wilms, J.; Kreikenbohm, A.; Law-Green, D.

    2015-09-01

    The EXTraS project (Exploring the X-ray Transient and variable Sky) is aimed at fullyexploring the serendipitous content of the XMM-Newton EPIC database in the timedomain. The project is funded within the EU/FP7-Cooperation Space framework and is carried out by a collaboration including INAF (Italy), IUSS (Italy), CNR/IMATI (Italy), University of Leicester (UK), MPE (Germany) and ECAP (Germany). The several tasks consist in characterise aperiodicvariability for all 3XMM sources, search for short-term periodic variability on hundreds of thousands sources, detect new transient sources that are missed by standard source detection and hence not belonging to the 3XMM catalogue, search for long term variability by measuring fluxes or upper limits for both pointed and slew observations, and finally perform multiwavelength characterisation andclassification. Screening and validation of the different products is essentially in order to reject flawed results, generated by the automatic pipelines. We present here the screening tool we developed in the form of a Graphical User Interface and our plans for a systematic screening of the different catalogues.

  15. Terrestrial Planets: Comparative Planetology

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Papers were presented at the 47th Annual Meteoritical Society Meeting on the Comparative planetology of Terrestrial Planets. Subject matter explored concerning terrestrial planets includes: interrelationships among planets; plaentary evolution; planetary structure; planetary composition; planetary Atmospheres; noble gases in meteorites; and planetary magnetic fields.

  16. TERRESTRIAL ECOSYSTEM SIMULATOR

    EPA Science Inventory

    The Terrestrial Habitats Project at the Western Ecology Division (Corvallis, OR) is developing tools and databases to meet the needs of Program Office clients for assessing risks to wildlife and terrestrial ecosystems. Because habitat is a dynamic condition in real-world environm...

  17. Large hierarchy from extra dimensions

    NASA Astrophysics Data System (ADS)

    Chaichian, M.; Kobakhidze, A. B.

    2000-04-01

    We argue that the familiar gauge hierarchy between the fundamental Planck scale MPl and the electroweak scale MW, can be naturally explained in higher dimensional theories with relatively large radii (Rc1/MPl) extra dimensions. In particular, we show that it is possible that the electroweak Higgs mass at high energies is of the order of MPl, but radiative corrections drive it to an infrared stable fixed-point ~MW at low energies thus inducing a large hierarchy without any fine tuning of parameters.

  18. Magnetic fields of the terrestrial planets

    NASA Technical Reports Server (NTRS)

    Russell, C. T.

    1993-01-01

    The four terrestrial planets, together with the Earth's Moon, provide a significant range of conditions under which dynamo action could occur. All five bodies have been visited by spacecraft, and from three of the five bodies (Earth, Moon and Mars) we have samples of planetary material upon which paleomagnetic studies have been undertaken. At the present time, only the Earth and Mercury appear to have a significant dipole magnetic field. However, the Moon, and possibly Mars, appear to have had ancient planetary dynamos. Venus does not now have a significant planetary magnetic field, and the high surface temperatures should have prevented the recording of evidence of any ancient magnetic field. Since the solidification of the solid inner core is thought to be the energy source for the terrestrial magnetic field, and since smaller bodies evolve thermally more rapidly than larger bodies, we conjecture that the terrestrial planets are today in three different phases of magnetic activity. Venus is in a predynamo phase, not having cooled to the point of core solidification. Mercury and the Earth are in the middle of their dynamo phase, with Mercury perhaps near the end of its activity. Mars and the Moon seem to be well past their dynamo phase. Much needs to be done in the study of the magnetism of the terrestrial planets. We need to characterize the multipole harmonic structure of the Mercury magnetic field plus its secular variation, and we need to analyze returned samples to attempt to unfold the long-term history of Mercury's dynamo. We need to more thoroughly map the magnetism of the lunar surface and to analyze samples obtained from a wider area of the lunar surface. We need a more complete survey of the present Martian magnetic field and samples from a range of different ages of Martian surface material. Finally, a better characterization of the secular variation of the terrestrial magnetic field is needed in order to unfold the workings of the terrestrial dynamo.

  19. Impact erosion of terrestrial planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Ahrens, Thomas J.

    1992-01-01

    I review current ideas about the nature of the planetesimals - composition, size distribution, and the planetary encounter velocity. Previous papers on accretion and erosion of planetary atmospheres as a result of multiple impacts are reviewed. Finally, the effects of blowing off a substantial fraction of the atmosphere from a terrestrial planet due to a single giant body impact are discussed.

  20. Higgs bosons in extra dimensions

    NASA Astrophysics Data System (ADS)

    Quiros, Mariano

    2015-04-01

    In this paper, motivated by the recent discovery of a Higgs-like boson at the Large Hadron Collider (LHC) with a mass mH?125 GeV, we review different models where the hierarchy problem is solved by means of a warped extra dimension. In the Randall-Sundrum (RS) model electroweak observables provide very strong bounds on the mass of KK modes which motivates extensions to overcome this problem. Two extensions are briefly discussed. One particular extension is based on the deformation of the metric such that it strongly departs from the AdS5 structure in the IR region while it goes asymptotically to AdS5 in the UV brane. This model has the IR brane close to a naked metric singularity (which is outside the physical interval) characteristic of soft-walls constructions. The proximity of the singularity provides a strong wave function renormalization for the Higgs field which suppresses the T and S parameters. The second class of considered extensions are based on the introduction of an extra gauge group in the bulk such that the custodial SU(2)R symmetry is gauged and protects the T parameter. By further enlarging the bulk gauge symmetry one can find models where the Higgs is identified with the fifth component of gauge fields and for which the Higgs potential along with the Higgs mass can be dynamically determined by the Coleman-Weinberg mechanism.

  1. Welfarism vs. extra-welfarism.

    PubMed

    Brouwer, Werner B F; Culyer, Anthony J; van Exel, N Job A; Rutten, Frans F H

    2008-03-01

    'Extra-welfarism' has received some attention in health economics, yet there is little consensus on what distinguishes it from more conventional 'welfarist economics'. In this paper, we seek to identify the characteristics of each in order to make a systematic comparison of the ways in which they evaluate alternative social states. The focus, though this is not intended to be exclusive, is on health. Specifically, we highlight four areas in which the two schools differ: (i) the outcomes considered relevant in an evaluation; (ii) the sources of valuation of the relevant outcomes; (iii) the basis of weighting of relevant outcomes and (iv) interpersonal comparisons. We conclude that these differences are substantive. PMID:18179835

  2. New Worlds Observer: system architecture for terrestrial planet finding

    NASA Astrophysics Data System (ADS)

    Arenberg, Jonathan W.; Polidan, Ronald S.; Glassman, Tiffany; Lo, Amy S.; Lillie, Charles F.

    2007-09-01

    The New Worlds Observer (NWO) is a mission concept for the detection and characterization of extra-solar planets. It employs an external starshade and a space telescope. The starshade suppressed the parent star's light making detection of the extrasolar planet possible. This paper reviews the proposed requirements for the Terrestrial Planet Finding (TPF) mission. Using current understanding of the performance and trades inherent in the NWO architecture it is shown how to construct the allowed design space for a NWO mission.

  3. Terrestrial photovoltaic measurements, 2

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The following major topics are discussed; (1) Terrestrial solar irradiance; (2) Solar simulation and reference cell calibration; and (3) Cell and array measurement procedures. Numerous related subtopics are also discussed within each major topic area.

  4. Origin of a peculiar extra U(1)

    SciTech Connect

    Barr, S.M.; Dorsner, I.

    2005-07-01

    The origin of a family-independent ''extra U(1)'', discovered by Barr, Bednarz, and Benesh and independently by Ma, and whose phenomenology has recently been studied by Ma and Roy, is discussed. Even though it satisfies anomaly constraints in a highly economical way, with just a single extra triplet of leptons per family, this extra U(1) cannot come from four-dimensional grand unification. However, it is shown here that it can come from a Pati-Salam scheme with an extra U(1), which explains the otherwise surprising cancellation of anomalies.

  5. The solar terrestrial observatory

    NASA Technical Reports Server (NTRS)

    Chappell, C. R.

    1978-01-01

    The larger system of the earth environment is controlled externally by electromagnetic and particle energy from the sun. Recent studies have shown that the sun is a variable star with changes in its radiation which produce significant effects in the earth's climate and weather. The study of the solar-terrestrial system requires simultaneous, long-duration observations of the different elements or 'links' in the solar-terrestrial chain. Many investigations must be conducted in space from a vantage point above the earth's atmosphere where all of the sun's emissions can be observed free from atmospheric distortion, where the magnetospheric particles and fields can be measured directly, and where the atmosphere can be observed on a global scale. The extension of the Shuttle on-orbit capability in connection with the development of the power module will offer an important near-term step in an evolutionary process leading toward a permanent manned Solar Terrestrial Observatory capability in low-earth orbit. Attention is given to the required solar-terrestrial measurements, the operation of the Solar Terrestrial Observatory, and an evolutionary approach to the Solar Terrestrial Observatory.

  6. How Do I Get Rid of Extra Skin After Weight Loss?

    MedlinePLUS

    ... Weight Loss? KidsHealth > Teens > Q&A > Body Image & Self-Esteem > How Do I Get Rid of Extra Skin ... Is Wise Nutrition & Fitness Center Body Image and Self-Esteem Strength Training Stretch Marks Contact Us Print Additional ...

  7. A Delicate Balance: An Examination of Lehigh University's Athletic Culture and Athletic Extra-Curriculum, 1866-1998

    ERIC Educational Resources Information Center

    Smith, Courtney Michelle

    2010-01-01

    This dissertation examines the history of Lehigh University's athletic culture and extra-curriculum from 1866 to 1998 and argues that both of those institutions served as the basis for identity within the undergraduate student body. Additionally, this dissertation argues that the athletic culture and extra-curriculum established Lehigh's identity

  8. Extra-solar Oort cloud encounters and planetary impact rates

    SciTech Connect

    Stern, A.

    1987-01-01

    Upper limits are estimated to the number density of extra-solar Oort clouds (ESOC) through which the solar system might pass and to the probable number of attendant planetary impacts by comets. All stars are assumed to have Oort clouds. The model is based on the observed stellar spatial density and the ratio of the total number density to the observed number density. It is estimated that 486 close stellar passages and 12,160 ESOC encounters may have occurred. Each encounter would have produced a shower of hyperbolic comets, with the results of 1-3 ESOC impacts with the earth. It is concluded that the great majority of terrestrial cratering events by comets have and will come from solar Oort cloud comets. 19 references.

  9. Fibered nulling telescope for extra-solar coronagraphy.

    PubMed

    Hnault, Franois

    2009-04-01

    A family of fibered nulling telescopes is described, based on the joint use of several recent suggested or demonstrated techniques, namely, pupil densification, multiaxial recombination and single-mode fiber modal filtering, and the use of a fully symmetric beam splitter arrangement. The concept seems appropriate for the realization of a spaceborne nulling telescope, searching for Jupiter-like extra-solar planets and a precursor of future missions, such as Darwin or terrestrial planet finder interferometer (TPF-I). However, it is generally not possible to satisfy at the same time two major requirements, being the depth and size of the central nulling area, and the global throughput for the observed planet. PMID:19340231

  10. Physics of Extra Dimensions Final Report

    SciTech Connect

    Csaba Csaki

    2007-12-19

    We provide the final report for Csaba Csaki's OJI project on "Physics of extra dimensions". It includes the summary of results of higgsless electroweak symmetry breaking, gauge-higgs unification, AdS/QCD and holographic technicolor, and chiral lattice theories from warped extra dimensions.

  11. Large Extra Dimensions and Quantum Black Holes

    NASA Astrophysics Data System (ADS)

    Loureiro, Karina Flavia

    2007-08-01

    Searches for large extra dimensions (LED) at various experiments, ranging from table-top to ultra-high energy cosmic ray experiments, are investigated within the confines of the ADD (Arkani-Hamed, Dimopoulos, Dvali) and RS (Randall-Sandrum) models. Black hole production as a probe into extra dimensions is discussed in the context of the Pierre Auger and ATLAS experiments.

  12. Earth and Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Jacobson, Seth A.; Walsh, Kevin J.

    2015-09-01

    The growth and composition of Earth is a direct consequence of planet formation throughout the Solar System. We discuss the known history of the Solar System, the proposed stages of growth and how the early stages of planet formation may be dominated by pebble growth processes. Pebbles are small bodies whose strong interactions with the nebula gas lead to remarkable new accretion mechanisms for the formation of planetesimals and the growth of planetary embryos. Many of the popular models for the later stages of planet formation are presented. The classical models with the giant planets on fixed orbits are not consistent with the known history of the Solar System, fail to create a high Earth/Mars mass ratio, and, in many cases, are also internally inconsistent. The successful Grand Tack model creates a small Mars, a wet Earth, a realistic asteroid belt and the mass-orbit structure of the terrestrial planets. In the Grand Tack scenario, growth curves for Earth most closely match a Weibull model. The feeding zones, which determine the compositions of Earth and Venus follow a particular pattern determined by Jupiter, while the feeding zones of Mars and Theia, the last giant impactor on Earth, appear to randomly sample the terrestrial disk. The late accreted mass samples the disk nearly evenly.

  13. Terrestrial Gravity Fluctuations

    NASA Astrophysics Data System (ADS)

    Harms, Jan

    2015-12-01

    Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10^-23 Hz^-1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of terrestrial gravity fluctuations will have great impact on the future development of GW detectors and high-precision gravimetry in general, and many open questions need to be answered still as emphasized in this article.

  14. Contrasting coloration in terrestrial mammals

    PubMed Central

    Caro, Tim

    2008-01-01

    Here I survey, collate and synthesize contrasting coloration in 5000 species of terrestrial mammals focusing on black and white pelage. After briefly reviewing alternative functional hypotheses for coloration in mammals, I examine nine colour patterns and combinations on different areas of the body and for each mammalian taxon to try to identify the most likely evolutionary drivers of contrasting coloration. Aposematism and perhaps conspecific signalling are the most consistent explanations for black and white pelage in mammals; background matching may explain white pelage. Evidence for contrasting coloration is being involved in crypsis through pattern blending, disruptive coloration or serving other functions, such as signalling dominance, lures, reducing eye glare or in temperature regulation has barely moved beyond anecdotal stages of investigation. Sexual dichromatism is limited in this taxon and its basis is unclear. Astonishingly, the functional significance of pelage coloration in most large charismatic black and white mammals that were new to science 150 years ago still remains a mystery. PMID:18990666

  15. Consumer Control of Terrestrial Ecosystems

    NASA Astrophysics Data System (ADS)

    Frank, D.

    2012-12-01

    More than half of the earth's terrestrial surface is grazed by large herbivores and their effects on plant and soil carbon and nitrogen processes are large and widespread. Yet the large effects of these animals on terrestrial processes have largely been ignored in global change models. This presentation will explore the many pathways that consumers affect short and long time-scale terrestrial nitrogen and carbon processes. Large herbivores influence the quality of soil organic matter and the size of the active (i.e., labile) pool of soil carbon and nitrogen in several ways. Herbivory leads to greater abundance of species producing low quality material in forest and dry grassland, via feeding preferentially on high quality forage, and high quality material in mesic grassland habitat, via the high quality of material that regrows after a plant is grazed. Defoliation stimulates the rate of root exudation that enhances rhizospheric processes and the availability of nitrogen in the plant rhizosphere. Herbivores also change the species composition of mycorrhizae fungal associates that influence plant growth and affect soil structure and the turnover rate of soil carbon. Recent radiocarbon measurements have revealed that herbivores also markedly affect the turnover dynamics of the large pool of old soil carbon. In Yellowstone Park, ungulates slow the mean turnover of the relatively old (i.e., slow and passive) 0 - 20 cm deep soil organic carbon by 350 years in upland, dry grassland and speed up that rate in slope-bottom, mesic grassland by 300 years. This represents a 650 year swing in the turnover period of old soil carbon across the Yellowstone landscape. By comparison, mean turnover time for the old pool of 0 - 10 cm deep soil organic carbon shifts by about 300 years across the steep climatic gradient that includes tropical, temperate, and northern hardwood forest, and tallgrass, shortgrass and desert grassland. This large body of evidence suggests consumers play a major role in global carbon cycling and likely are important regulators of the terrestrial response to climate change.

  16. Theoretical investigation of isotopic anomaly of xenon in carbonaceous chondrites and other terrestrial and extra-terrestrial samples

    NASA Technical Reports Server (NTRS)

    Sabu, D. D.

    1974-01-01

    The composition of Xe released from carbonaceous chondrites between 600 and 1000 C, particularly its isotopic trapped forms, is analyzed. Data show trapped Xe to have the following forms: Xe-124, 126, 130, 131, 132, 134, and 136. Attempts were also made to explain the Xe anomaly by mass fractionation as well as determine the relationship between metoritic trapped Xe and solar Xe.

  17. Effects of geophysical extra-terrestrial and terrestrial physical stimuli on living organisms - Effects of gravity fields on living organisms

    NASA Technical Reports Server (NTRS)

    Saunders, R. J. F.

    1972-01-01

    The biologic effects of greatly reduced gravity resulting from space flight are examined. Aspects of U.S. space biology during the period from 1960 to 1972 are discussed, giving attention to the Discoverer satellites, the Gemini series, the OV1-4 satellite, the biosatellite project, the orbiting frog otolith experiment, and the Apollo program. Other studies considered are related to the effects of galactic particles on nonproliferating cells, a recoverable tissue culture experiment, cell cycle maintenance in human lung cells, and effects of space flight on circadian rhythms. Viking will land on the planet Mars in 1975 in search for life forms.

  18. Non-mass-dependent Isotopic Fractionation Processes: Mechanisms and Recent Observations in Terrestrial and Extra-terrestrial Environments

    NASA Astrophysics Data System (ADS)

    Thiemens, M. H.

    2003-12-01

    There were several key observations, which were made almost around the same time, that led to studies in the fields of stable isotope geochemistry and cosmochemistry. First, it was the physicochemical formalism for isotope effects, particularly the determination of the position of equilibrium in isotopic exchange reactions. Urey (1947) and Bigeleisen and Mayer (1947) demonstrated that the position of isotope exchange in a chemical reaction may be calculated with high precision. The difference in chemical behavior for isotopically substituted molecules in this specific instance arises from quantum mechanical effects. The vibrating molecule is energetically represented as a harmonic oscillator. Thus, in the case of isotopic substituted molecules, the quantized energy levels vary with the heavier species possessing lower vibrational frequencies. As a result, the isotopically substituted molecules possess slightly stronger bond strengths, which can be calculated with high precision. These can also be measured spectroscopically. Furthermore, since vibrational frequencies are temperature dependent, the partitioning of isotopes between two molecules is temperature dependent and the observed isotopic differences may be used as a temperature index for the equilibrium process of interest.This phenomenon forms the basis for the formulations of Urey (1947) and Bigeleisen and Mayer (1947) for the temperature dependence of isotopic exchange between two molecules. With the nearly simultaneous development of the isotope-ratio mass spectrometer by Nier et al. (1947), the potential for application of stable isotopes was created. Other isotopic fractionation processes are observed in kinetics, diffusion, evaporation-condensation, crystallization, and biology (e.g., photosynthesis, respiration, nitrogen fixation, sulfate reduction, and transpiration). The concomitant isotopic fractionations can also be used to provide details of the relevant process.Although, the conventional isotope effects vary widely in the physicochemical basis for their origin, they all are dependent upon relative isotopic mass differences. The first quantitative discussion of the mass dependence of isotope effects was given by Hulston andThode (1965), who showed that conventional isotope effects alter the isotope ratios in a manner strictly dependent upon relative mass differences. Specifically, the changes in ?33S and ?34S are shown to be highly correlated such that the change in ?33S is half that of ?34S. The mass range in the ?33S is 1 amu (33-32 amu) and for ?34S is 2 amu (34-32 amu). Thus,?33S?0.5?34Sis observed and arises due to the magnitude of the relative isotopic mass differences. The focus of the paper of Hulston and Thode was to utilize meteoritic stable-isotope-ratio measurements as a mechanism to resolve nuclear (nucleosynthetic or spallogenic) processes from non-nuclear processes. The fundamental assumption in this work was, based upon the assumption that all conventional physicochemical processes produce correlated mass-dependent arrays, that any deviation from this relation must reflect a nuclear process. The core assumption for this assertion was that any physical or chemical process may not lead to a variance in stable isotope ratio that does not depend upon mass differences.Clayton et al. (1973) observed that the high-temperature calcium-aluminum inclusions (CAIs) present in the carbonaceous chondrite Allende possess an oxygen isotope composition of ?17O??18O, rather than the expected mass-dependent ?17O?0.5?18O. It was suggested that this anomalous isotopic composition must derive from a nuclear, rather than chemical process. In general, an equality ?17O=?18O may arise in two ways, either by alteration of 17O and 18O by equal amounts or, by addition/subtraction of pure 16O. Models for supernova processes had shown that for certain conditions, essentially pure 16O is produced. Clayton et al. argued that it is unlikely that 17O and 18O would be equally altered, thus the supernova event was deemed the most plausible mechanism to a

  19. Body Fluids Monitor

    NASA Technical Reports Server (NTRS)

    Siconolfi, Steven F. (Inventor)

    2000-01-01

    Method and apparatus are described for determining volumes of body fluids in a subject using bioelectrical response spectroscopy. The human body is represented using an electrical circuit. Intra-cellular water is represented by a resistor in series with a capacitor; extra-cellular water is represented by a resistor in series with two parallel inductors. The parallel inductors represent the resistance due to vascular fluids. An alternating, low amperage, multifrequency signal is applied to determine a subject's impedance and resistance. From these data, statistical regression is used to determine a 1% impedance where the subject's impedance changes by no more than 1% over a 25 kHz interval. Circuit component, of the human body circuit are determined based on the 1% impedance. Equations for calculating total body water, extra-cellular water, total blood volume, and plasma volume are developed based on the circuit components.

  20. Extra-articular Manifestations in Rheumatoid Arthritis

    PubMed Central

    Cojocaru, Manole; Cojocaru, Inimioara Mihaela; Silosi, Isabela; Vrabie, Camelia Doina; Tanasescu, R

    2010-01-01

    ABSTRACT Rheumatoid arthritis (RA) is a systemic autoimmune disease whose main characteristic is persistent joint inflammation that results in joint damage and loss of function. Although RA is more common in females, extra-articular manifestations of the disease are more common in males. The extra-articular manifestations of RA can occur at any age after onset. It is characterised by destructive polyarthritis and extra-articular organ involvement, including the skin, eye, heart, lung, renal, nervous and gastrointestinal systems. The frequence of extra-articular manifestations in RA differs from one country to another. Extra-articular organ involvement in RA is more frequently seen in patients with severe, active disease and is associated with increased mortality. Incidence and frequence figures for extra-articular RA vary according to study design. Extra-articular involvement is more likely in those who have RF and/or are HLA-DR4 positive. Occasionally, there are also systemic manifestations such as vasculitis, visceral nodules, Sjgren's syndrome, or pulmonary fibrosis present. Nodules are the most common extra-articular feature, and are present in up to 30%; many of the other classic features occur in 1% or less in normal clinic settings. Sjgren's syndrome, anaemia of chronic disease and pulmonary manifestations are relatively common in 6-10%, are frequently present in early disease and are all related to worse outcomes measures of rheumatoid disease in particular functional impairment and mortality. The occurrence of these systemic manifestations is a major predictor of mortality in patients with RA. This paper focuses on extra-articular manifestations, defined as diseases and symptoms not directly related to the locomotor system. PMID:21977172

  1. Searching for extra-dimensions at CMS

    NASA Astrophysics Data System (ADS)

    Benucci, Leonardo

    2009-06-01

    A possible solution to the hierarchy problem is the presence of extra space dimensions beyond the three ones which are known from our everyday experience. The phenomenological ADD model of large extra-dimensions predicts a ETmiss +jet signature. Randall-Sundrum-type extra-dimensions predict di-lepton and di-jet resonances. This contribution addresses an overview of experimental issues and discovery potential for these new particles at the LHC, focusing on perspectives with the CMS detector during early data taking.

  2. Terrestrial planet formation.

    PubMed

    Righter, K; O'Brien, D P

    2011-11-29

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids. PMID:21709256

  3. The Terrestrial Silica Pump

    PubMed Central

    Carey, Joanna C.; Fulweiler, Robinson W.

    2012-01-01

    Silicon (Si) cycling controls atmospheric CO2 concentrations and thus, the global climate, through three well-recognized means: chemical weathering of mineral silicates, occlusion of carbon (C) to soil phytoliths, and the oceanic biological Si pump. In the latter, oceanic diatoms directly sequester 25.8 Gton C yr?1, accounting for 43% of the total oceanic net primary production (NPP). However, another important link between C and Si cycling remains largely ignored, specifically the role of Si in terrestrial NPP. Here we show that 55% of terrestrial NPP (33 Gton C yr?1) is due to active Si-accumulating vegetation, on par with the amount of C sequestered annually via marine diatoms. Our results suggest that similar to oceanic diatoms, the biological Si cycle of land plants also controls atmospheric CO2 levels. In addition, we provide the first estimates of Si fixed in terrestrial vegetation by major global biome type, highlighting the ecosystems of most dynamic Si fixation. Projected global land use change will convert forests to agricultural lands, increasing the fixation of Si by land plants, and the magnitude of the terrestrial Si pump. PMID:23300825

  4. Batteries for terrestrial applications

    SciTech Connect

    Kulin, T.M.

    1998-07-01

    Extensive research has been conducted in the design and manufacture of very long life vented and sealed maintenance free nickel-cadmium aircraft batteries. These batteries have also been used in a number of terrestrial applications with good success. This study presents an overview of the Ni-Cd chemistry and technology as well as detailed analysis of the advantages and disadvantages of the Ni-Cd couple for terrestrial applications. The performance characteristics of both sealed and vented Ni-Cd's are presented. Various charge algorithms are examined and evaluated for effectiveness and ease of implementation. Hardware requirements for charging are also presented and evaluated. The discharge characteristics of vented and sealed Ni-Cd's are presented and compared to other battery chemistries. The performance of Ni-Cd's under extreme environmental conditions is also compared to other battery chemistries. The history of various terrestrial applications is reviewed and some of the lessons learned are presented. Applications discussed include the NASA Middeck Payload Battery, Raytheon Aegis Missile System Battery, THAAD Launcher battery, and the Titan IV battery. The suitability of the Ni-Cd chemistry for other terrestrial applications such as electric vehicles and Uninterruptible Power Supply is discussed.

  5. Terrestrial planet formation

    PubMed Central

    Righter, K.; O’Brien, D. P.

    2011-01-01

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (∼106 y), followed by planetesimals to embryos (lunar to Mars-sized objects; few × 106 y), and finally embryos to planets (107–108 y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids. PMID:21709256

  6. Terrestrial analogs to Mars

    NASA Technical Reports Server (NTRS)

    Farr, T. G.; Arcone, S.; Arvidson, R.; Baker, V.; Barlow, N.; Beaty, D.; Bell, M.; Blankenship, D.; Bridges, N.; Briggs, G.; Bulmer, M.; Carsey, F.; Clifford, S.; Craddock, R.; Dickerson, P.; Duxbury, N.

    2002-01-01

    It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing.

  7. INTRODUCED TERRESTRIAL SPECIES (FUTURE)

    EPA Science Inventory

    These data represent predicted future potential distributions of terrestrial plants, animals, and pathogens non-native to the Middle-Atlantic region. These data are available for 8-digit HUCs. The data are a weighted proportion of appropriate habitat overlapped by the potential...

  8. Mars: destructive and constructive processes in its crust reflecting tendencies of leveling angular momenta of tropics and extra-tropics

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2009-04-01

    Mars: destructive and constructive processes in its crust reflecting tendencies of leveling angular momenta of tropics and extra-tropics. G. Kochemasov IGEM of the Russian Academy of Sciences A globular shape of rotating celestial bodies means that their tropical and extra-tropical belts have significantly different angular momenta. But such unevenness in a single body is disturbing because it increases level of tectonic stresses and energetic state what is against natural trends for minimizing these characteristics. To level partly this inequality bodies tend to diminish radius and mass in tropics and increase them in extra-tropics. Traces of these destructive and constructive actions are fixed in planetary geospheres of different classes of celestial bodies: Sun, planets, satellites, and asteroids. The remote geologic mapping of Mars reveals these traces rather obviously. "Mysterious" contact zone of the martian lowlands and highlands with obvious traces of destruction expressed in widespread development of chaotic and fretted terrains is a good evidence that could be considered in comparison with the equatorial and tropical belts of some other planetary bodies [1]. At Earth the wide planetary long tropical zone is marked by its destruction. It is demonstrated by development of numerous islands of the Archipelago between the South-East Asia and Australia. In Africa and South America huge depressions of the Congo and Amazon Rivers develops where the Archean crust is subsided to depths of more than 2 km. In the Pacific along the equator numerous islands of Micronesia occur. Subsidence of the basaltic oceanic crust is followed by an intensive folding and faulting of basalt and sedimentary layers as a larger mass must be held by a smaller space (a planetary radius is diminished). Seismicity of the tropical zone is significantly higher than outside of it that means more intensive destruction in the crust and the upper mantle of tropics. Mantle derived diamonds are more nitrogen rich (thus, heavier) in extra-tropical zones than in Africa where even unique diamonds with boron (it makes the carbon crystal less dense). Changes in the atmosphere follow the same trend. Its heavier components like carbon dioxide, methane, and ozone are less abundant in tropics and enrich the higher and lower latitudes. The oceanic level at the higher latitudes is 2 to 2.5 meters higher than at the equator that is usually explained by varying water temperature and salinity. In the anthroposphere the observed geospheric trend is visible very clearly. People with small mass and stature develop in the equatorial (in a wide sense) region of Earth. Not depending on a main morphological type (great race or geographical branch) people of this belt is significantly smaller in mass and stature than their counterparts of more northern and southern latitudes). This observation is supported by the dendrosphere where the mean timber density in the equatorial regions is somewhat less than in the extra-equatorial regions of tropics: for folia trees 693 kg/m3 against 757 kg/m3 [2]. On Iapetus the wide equatorial zone of the bright trailing hemisphere is distinguished by relatively numerous craters with darkened floors. The Sun's photosphere is "perforated" by darker colder spots deep up to 300 (maybe more?) km - famous solar spots long to 200000 km and smaller pores. In the chromosphere there is a remarkable loss of "heavy" Ca ion from this region (compare with a loss of methane from the equatorial region of Saturn)[3]. Though Mars' geospheres are studied not so fully as the Earth's ones, its surface mapping allowed to show that a special kind of craters - so called pedestal craters - are broadly developed polarward of 40? N and S latitudes [4, 5]. Usually they are considered as impact craters but more correctly they should be assigned to normal volcanic features expulsing volatile-rich silicate material (a kind of mud, thus "mud volcanoes'). Usually they are less than 10 km in diameter, morphologically fresh and surrounded by wide pedestals several times wider than crater bowls (what is one of indicators against an impact origin). Normally they occur on Amazonian and Hesperian formations. An intensive volcanism through pedestal craters in extra-tropic belts should be compared with intensive plume-driven basaltic terrestrial volcanism also in extra-tropics - both are constructive events. References: [1] Kochemasov G.G. Destruction of the martian tropical belt as means of the angular momentum equilibration between the tropical and extra-tropical regions // Geophys. Res. Abstr., V. 10, 2008, EGU2008-A-01270; [2] Timbers of the world, v.1,TRADA/The construction press Ltd.,1979; Timbers of the world, v.2,TRADA/The construction press Ltd, 1980; [3] Kochemasov G.G. Tectonics of rotating celestial globes // Vernadsky-Brown microsymposium 48, 20-22 Oct. 2008, Moscow, Abstr. m48_20; [4] Kadish S.J., Head J.W., Barlow N.G. Pedestal craters on Mars: distribution, characteristics, and implications for Amazonian climate change // LPS XXXIX, 2008, Abstract 1766.pdf.; [5] Kadish S.J., Head J.W., and Barlow N.G. Determining the ages of mid-latitude pedestal craters // Vernadsky-Brown microsymposium 48, 20-22 Oct. 2008, Moscow, Abstr. m48_17.

  9. Metabolic assessments during extra-vehicular activity.

    PubMed

    Osipov YuYu; Spichkov, A N; Filipenkov, S N

    1998-01-01

    Extra-vehicular activity (EVA) has a significant role during extended space flights. It demonstrates that humans can survive and perform useful work outside the Orbital Space Stations (OSS) while wearing protective space suits (SS). When the International Space Station 'Alpha' (ISSA) is fully operational, EVA assembly, installation, maintenance and repair operations will become an everyday repetitive work activity in space. It needs new ergonomic evaluation of the work/rest schedule for an increasing of the labor amount per EVA hour. The metabolism assessment is a helpful method to control the productivity of the EVA astronaut and to optimize the work/rest regime. Three following methods were used in Russia to estimate real-time metabolic rates during EVA: 1. Oxygen consumption, computed from the pressure drop in a high pressure bottle per unit time (with actual thermodynamic oxygen properties under high pressure and oxygen leakage taken into account). 2. Carbon dioxide production, computed from CO2 concentration at the contaminant control cartridge and gas flow rate in the life support subsystem closed loop (nominal mode) or gas leakage in the SS open loop (emergency mode). 3. Heat removal, computed from the difference between the temperatures of coolant water or gas and its flow rate in a unit of time (with assumed humidity and wet oxygen state taken into account). Comparison of heat removal values with metabolic rates enables us to determine the thermal balance during an operative medical control of EVA at "Salyut-6", "Salyut-7" and "Mir" OSS. Complex analysis of metabolism, body temperature and heat rate supports a differential diagnosis between emotional and thermal components of stress during EVA. It gives a prognosis of human homeostasis during EVA. Available information has been acquired into an EVA data base which is an effective tool for ergonomical optimization. PMID:11541598

  10. Metabolic assessments during extra-vehicular activity

    NASA Astrophysics Data System (ADS)

    Osipov, Yu. Yu.; Spichkov, A. N.; Filipenkov, S. N.

    Extra-vehicular activity (EVA) has a significant role during extended space flights. It demonstrates that humans can survive and perform useful work outside the Orbital Space Stations (OSS) while wearing protective space suits (SS). When the International Space Station 'Alpha'(ISSA) is fully operational, EVA assembly, installation, maintenance and repair operations will become an everyday repetitive work activity in space. It needs new ergonomic evaluation of the work/rest schedule for an increasing of the labor amount per EVA hour. The metabolism assessment is a helpful method to control the productivity of the EVA astronaut and to optimize the work/rest regime. Three following methods were used in Russia to estimate real-time metabolic rates during EVA: 1. Oxygen consumption, computed from the pressure drop in a high pressure bottle per unit time (with actual thermodynamic oxygen properties under high pressure and oxygen leakage taken into account). 2. Carbon dioxide production, computed from CO 2 concentration at the contaminant control cartridge and gas flow rate in the life support subsystem closed loop (nominal mode) or gas leakage in the SS open loop (emergency mode). 3. Heat removal, computed from the difference between the temperatures of coolant water or gas and its flow rate in a unit of time (with assumed humidity and wet oxygen state taken into account). Comparison of heat removal values with metabolic rates enables us to determine the thermal balance during an operative medical control of EVA at "Salyut-6", "Salyut-7" and "Mir" OSS. Complex analysis of metabolism, body temperature and heat rate supports a differential diagnosis between emotional and thermal components of stress during EVA. It gives a prognosis of human homeostasis during EVA. Available information has been acquired into an EVA data base which is an effective tool for ergonomical optimization.

  11. Feeling Extra Forgetful May Signal Dementia Ahead

    MedlinePLUS

    ... fullstory_155394.html Feeling Extra Forgetful May Signal Dementia Ahead Older women who thought their memory was ... feeling unusually forgetful may be a sign that dementia will develop later on, a new study suggests. " ...

  12. Radiology and Children: Extra Care Required

    MedlinePLUS

    ... gov/ consumer/ update s/ radiolog y_ k ids062308. html Radiology & Children: Extra Care Required M ost everyone knows ... Image Gently campaign include the Society for Pediatric Radiology, the American College of Radiology, the Ameri- can ...

  13. Volcanic ash - Terrestrial versus extraterrestrial

    NASA Technical Reports Server (NTRS)

    Okeefe, J. A.

    1976-01-01

    A principal difference between terrestrial and extraterrestrial lavas may consist in the greater ability of terrestrial lavas to form thin films (like those of soap bubbles) and hence foams. It would follow that, in place of the pumice and spiny shards found in terrestrial volcanic ash, an extraterrestrial ash should contain minute spherules. This hypothesis may help to explain lunar microspherules.

  14. The Terrestrial Planet Finder and Darwin Missions

    NASA Technical Reports Server (NTRS)

    Danchi, William C.

    2004-01-01

    Both in the United States and in Europe, teams of scientists and engineers are exploring the feasibility of the Terrestrial Planet Finder (TPF) and Darwin missions, which are designed to search for Earth-like planets in the habitable zone of nearby stars. In the US, the TPF Science Working Group is studying four options - small (4m by 6 m primary mirror) and large (4m by 10 m primary mirror) coronagraphs for planet detection at visible wavelengths, and structurally connected and free-flyer interferometers at thermal infrared wavelengths. The US TPF-SWG is charged with selecting an option for NASA by the end of 2006. In Europe the Darwin Terrestrial Exo-planet Advisory Team (TE- SAT) is exploring the free-flyer interferometer option only at this time. I will discuss the vurtures and difficulties of detecting and characterizing extra-solar planets in both wavelength regions as well as some of the technical challenges and progress in the past year.

  15. Investigation of the extra-extra-push by pre-scission neutron measurements with DEMON

    SciTech Connect

    Rudolf, Gerard

    1998-02-15

    The objective of this talk is to present a simple method to calculate pre- and post-scission neutron multiplicities in the frame of the Bass model. This method is of particular interest for very heavy systems for which an extra-extra-push is supposed to hinder fusion. The multiplicities calculated by the model are compared to published data covering a broad range of projectile and target masses, and to more recent ones obtained with the help of the Demon detector and addressing specifically the existence of the extra-extra-push.

  16. Forming Terrestrial Planets and Delivering Their Water

    NASA Astrophysics Data System (ADS)

    Walsh, Kevin John

    2015-08-01

    Building models capable of successfully matching the Terrestrial Planet's basic physical and orbital properties has proven difficult. Meanwhile, improved estimates of the nature of water-rich material accreted by the Earth, along with the timing of its delivery, have added even more constraints to match. While the outer Asteroid Belt seemingly provides a source for water-rich planetesimals, models that delivered enough of them to the still-forming Terrestrial Planets typically failed on other basic constraints - such as the mass of Mars.Recent models of Terrestrial Planet Formation have explored how the gas-driven migration of the Giant Planets can solve long-standing issues with the Earth/Mars size ratio. This model is forced to reproduce the orbital and taxonomic distribution of bodies in the Asteroid Belt from a much wider range of semimajor axis then previously considered. In doing so, it also provides a mechanism to feed planetesimals from between and beyond the Giant Planet formation region to the still-forming Terrestrial Planets.

  17. Satellite-Terrestrial Network Interoperability

    NASA Technical Reports Server (NTRS)

    vonDeak, Thomas C.

    1998-01-01

    The developing national and global information infrastructures (NII/GII) are being built upon the asynchronous transfer mode (ATM) telecommunications protocol and associated protocol standards. These protocols are themselves under development through the telecommunications standards process defined by the International Telecommunications Union (ITU), which as a body is sanctioned by the United Nations. All telecommunications manufacturers use these standards to create products that can interoperate. The ITU has recognized the ATM Forum as the instrument for the development of ATM protocols. This forum is a consortium of industry, academia, and government entities formed to quickly develop standards for the ATM infrastructure. However, because the participants represent a predominately terrestrial network viewpoint, the use of satellites in the national and global information infrastructures could be severely compromised. Consequently, through an ongoing task order, the NASA Lewis Research Center asked Sterling Software, Inc., to communicate with the ATM Forum in support of the interoperability of satellite-terrestrial networks. This year, Dr. Raj Jain of the Ohio State University, under contract to Sterling, authored or coauthored 32 explanatory documents delivered to the ATM Forum in the areas of Guaranteed Frame Rate for Transmission Control Protocol/Internet Protocol (TCP/IP), Available Bit Rate, performance testing, Variable Bit Rate voice over ATM, TCP over Unspecified Bit Rate+, Virtual Source/Virtual Destination, and network management. These contributions have had a significant impact on the content of the standards that the ATM Forum is developing. Some of the more significant accomplishments have been: (1) The adoption by the ATM Forum of a new definition for Message-In, Message-Out latency; and (2) Improved text (clearer wording and newly defined terms) for measurement procedures, foreground and background traffic, and scalable configuration in the latency and throughput sections of the Performance Testing Baseline Text.

  18. Comparative Climatology of Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Mackwell, Stephen J.; Simon-Miller, Amy A.; Harder, Jerald W.; Bullock, Mark A.

    Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons to a future volume. Our authors have taken on the task to look at climate on the terrestrial planets in the broadest sense possible — by comparing the atmospheric processes at work on the four terrestrial bodies, Earth, Venus, Mars, and Titan (Titan is included because it hosts many of the common processes), and on terrestrial planets around other stars. These processes include the interactions of shortwave and thermal radiation with the atmosphere, condensation and vaporization of volatiles, atmospheric dynamics, chemistry and aerosol formation, and the role of the surface and interior in the long-term evolution of climate. Chapters herein compare the scientific questions, analysis methods, numerical models, and spacecraft remote sensing experiments of Earth and the other terrestrial planets, emphasizing the underlying commonality of physical processes. We look to the future by identifying objectives for ongoing research and new missions. Through these pages we challenge practicing planetary scientists, and most importantly new students of any age, to find pathways and synergies for advancing the field. In Part I, Foundations, we introduce the fundamental physics of climate on terrestrial planets. Starting with the best studied planet by far, Earth, the first chapters discuss what is known and what is not known about the atmospheres and climates of the terrestrial planets of the solar system and beyond. In Part II, Greenhouse Effect and Atmospheric Dynamics, we focus on the processes that govern atmospheric motion and the role that general circulation models play in our current understanding. In Part III, Clouds and Hazes, we provide an in-depth look at the many effects of clouds and aerosols on planetary climate. Although this is a vigorous area of research in the Earth sciences, and very strongly influences climate modeling, the important role that aerosols and clouds play in the climate of all planets is not yet well constrained. This section is intended to stimulate further research on this critical subject. The study of climate involves much more than understanding atmospheric processes. This subtlety is particularly appreciated for Earth, where chemical cycles, geology, ocean influences, and biology are considered in most climate models. In Part IV, Surface and Interior, we look at the role that geochemical cycles, volcanism, and interior mantle processes play in the stability and evolution of terrestrial planetary climates. There is one vital commonality between the climates of all the planets of the solar system: Regardless of the different processes that dominate each of the climates of Earth, Mars, Venus, and Titan, they are all ultimately forced by radiation from the same star, albeit at variable distances. In Part V, Solar Influences, we discuss how the Sun's early evolution affected the climates of the terrestrial planets, and how it continues to control the temperatures and compositions of planetary atmospheres. This will be of particular interest as models of exoplanets, and the influences of much different stellar types and distances, are advanced by further observations. Comparisons of atmospheric and climate processes between the planets in our solar system has been a focus of numerous conferences over the past decade, including the Exoclimes conference series. In particular, this book project was closely tied to a conference on Comparative Climatology of Terrestrial Planets that was held in Boulder, Colorado, on June 25-28, 2012. This book benefited from the opportunity for the author teams to interact and obtain feedback from the broader community, but the chapters do not in general tie directly to presentations at the conference. The conference, which was organized by a diverse group of atmospheric and climate scientists led by Mark Bullock and Lori Glaze, sought to build connections between the various communities, focusing on synergies and complementary capabilities. Discussion panels at the end of most sessions served to build connections between planetary, solar, astrophysics, and Earth climate scientists. These presentations and discussions allowed broadening of the author teams and tuning of the material in each chapter. Comparative Climatology of Terrestrial Planets is the 38th book in the University of Arizona Press Space Sciences Series. The support and guidance from General Editor Richard Binzel has been critical in timely production of a quality volume. Renée Dotson of the Lunar and Planetary Institute, with support from Elizabeth Cunningham and Katy Buckaloo, provided outstanding help in the management of the book project and especially in the preparation of the chapters for publication. Her quiet reminders and attention to detail are critical in making the Space Science Series such an asset for the planetary science community. As for so many other books in this series, William Hartmann used his artistic skills to masterfully capture the book's theme. Much gratitude is owed to Adriana Ocampo of NASA Headquarters for her support of both the conference and book projects and her shepherding of the NASA contributions from the diverse groups within the Science Mission Directorate. Equally, James Green and Jonathan Rall of NASA Headquarters provided the financial resources and corporate oversight that helped make this book project such a success.

  19. Sliding GAIT Algorithm for the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE)

    NASA Technical Reports Server (NTRS)

    Townsend, Julie; Biesiadecki, Jeffrey

    2012-01-01

    The design of a surface robotic system typically involves a trade between the traverse speed of a wheeled rover and the terrain-negotiating capabilities of a multi-legged walker. The ATHLETE mobility system, with both articulated limbs and wheels, is uniquely capable of both driving and walking, and has the flexibility to employ additional hybrid mobility modes. This paper introduces the Sliding Gait, an intermediate mobility algorithm faster than walking with better terrain-handling capabilities than wheeled mobility.

  20. An instrument for elemental and isotopic abundance characterization of extra-terrestrial materials

    NASA Astrophysics Data System (ADS)

    Veryovkin, I. V.; Calaway, W. F.; Moore, J. F.; Pellin, M. J.; Savina, M. R.; King, B. V.; Petravi?, M.; Burnett, D. S.

    2002-12-01

    Samples returned from the Genesis and Stardust missions of NASA's Discovery Program require quantitative analysis at sensitivities unobtainable with present instruments. This has driven development of a new generation of instruments for laser-post-ionization secondary neutral mass spectrometry (laser-SNMS). Construction of a prototype time-of-flight (TOF) SNMS instrument has been completed recently at Argonne National Laboratory (ANL) and testing began in August 2002. This instrument is optimized for laser post-ionization of sputtered neutrals and is capable of locating and analyzing individual sub-micrometer interstellar particles on a sample stage for Stardust or determining elemental concentrations in shallow implants at ultra-trace levels for Genesis. Post-ionization can be accomplished with a variety of laser sources. These include high repetition rate tunable Ti-sapphire lasers for ultra-trace analysis of a single element and two vacuum ultraviolet (VUV) light sources for simultaneous ionization of most atomic and molecular species in the sample. The two VUV lasers are an F2 laser with a fixed wavelength of 157 nm and the self-amplified spontaneous emission free-electron laser (SASE FEL) capable of generating tunable VUV at wavelengths down to 60 nm. Fundamental physical theory of ion sputtering forms the scientific basis of the approach used to design the instrument. An ion optics design for the instrument was perfected through extensive three-dimensional computer simulations using SIMION software. Realistic sets of photo-ions were calculated using formalisms derived from sputtering theory. Their trajectories in various instrument designs were then traced by SIMION. Finally, results of the simulations were processed to estimate instrument capabilities including resolution and useful yield. This same approach proved accurate and quantitative during tests of an existing TOF SNMS instrument demonstrating the reliability of the simulation method. The completed prototype instrument and results of recent tests will be presented. This work is supported by the U. S. Department of Energy, BES-Materials Sciences, under Contract W-31-109-ENG-38 and in part by a contract from NASA's Office of Space Science's Cosmochemistry Program.

  1. Two systems analyses of SETI. [microwave Search for Extra-Terrestrial Intelligence

    NASA Technical Reports Server (NTRS)

    Machol, R. E.

    1976-01-01

    The problem of receiving and identifying a single microwave signal transmitted by extraterrestrial intelligent beings is analyzed in the cases where the signal is designed to catch our attention and the signal is designed for internal purposes of another civilization. Six variables which yield uncertainty as to the exact signal which should be searched for are described: polarization, modulation, flux level, direction, frequency (including bandwidth and drift rate), and time. It is shown that if all reasonable variations of these parameters are to be examined sequentially for 1000 seconds, the search would take over a million times longer than the age of the Universe. Ways to simplify the search are considered, including widening the frequency bin, selecting specific targets, cutting the observation time, using a Fourier transform device for data processing, and building larger antennas as well as better low-noise receivers.

  2. Energy Systems - Present, Future: Extra Terrestrials, Grades 7, 8, 9,/Science.

    ERIC Educational Resources Information Center

    National Science Teachers Association, Washington, DC.

    The 12 lessons presented in this guide are structured so that they may be integrated into science lessons in 7th-, 8th-, or 9th-grades. Suggestions are made for extension of study. Lessons are approached through classroom role-playing of outer space visitors who seek to understand energy conversion principles used on Earth. Major emphasis is

  3. Making Friends with an Extra-Terrestrial: Conversation Skills and Friendship Formation in Young Children.

    ERIC Educational Resources Information Center

    Parker, Jeffrey G.; Gottman, John M.

    A novel paradigm was developed and two studies conducted to test the contribution of six conversational skills to children's friendship formation. In study 1, 4- and 5-year-olds individually played for 30 minutes with a 2-foot-tall talking doll. The doll contained a wireless hidden receiver/speaker enabling a concealed female assistant to converse…

  4. Search for Extra-Terrestrial planets: The DARWIN mission - Target Stars and Array Architectures

    NASA Astrophysics Data System (ADS)

    Kaltenegger, Lisa

    2005-04-01

    The DARWIN mission is an Infrared free flying interferometer mission based on the new technique of nulling interferometry. Its main objective is to detect and characterize other Earth-like planets, analyze the composition of their atmospheres and their capability to sustain life, as we know it. DARWIN is currently in definition phase. This PhD work that has been undertaken within the DARWIN team at the European Space Agency (ESA) addresses two crucial aspects of the mission. Firstly, a DARWIN target star list has been established that includes characteristics of the target star sample that will be critical for final mission design, such as, luminosity, distance, spectral classification, stellar variability, multiplicity, location and radius of the star. Constrains were applied as set by planet evolution theory and mission architecture. Secondly, a number of alternative mission architectures have been evaluated on the basis of interferometer response as a function of wavelength, achievable modulation efficiency, number of telescopes and starlight rejection capabilities. The study has shown that the core mission goals should be achievable with a lower level of complexity as compared to the current baseline configuration.

  5. Combustion of Metals in Reduced-Gravity and Extra Terrestrial Environments

    NASA Technical Reports Server (NTRS)

    Branch, M.C.; Abbud-Madrid, A.; Daily, J. W.

    1999-01-01

    The combustion of metals is a field with important practical applications in rocket propellants, high-temperature flames, and material synthesis. Also, the safe operation of metal containers in high-pressure oxygen systems and with cryogenic fuels and oxidizers remains an important concern in industry. The increasing use of metallic components in spacecraft and space structures has also raised concerns about their flammability properties and fire suppression mechanisms. In addition, recent efforts to embark on unmanned and manned planetary exploration, such as on Mars, have also renewed the interest in metal/carbon-dioxide combustion as an effective in situ resource utilization technology. In spite of these practical applications, the understanding of the combustion properties of metals remains far behind that of the most commonly used fuels such as hydrocarbons. The lack of understanding is due to the many problems unique to metal- oxidizer reactions such as: low-temperature surface oxidation prior to ignition, heterogeneous reactions, very high combustion temperatures, product condensation, high emissivity of products, and multi-phase interactions. Very few analytical models (all neglecting the influence of gravity) have been developed to predict the burning characteristics and the flame structure details. Several experimental studies attempting to validate these models have used small metal particles to recreate gravity-free conditions. The high emissivity of the flames, rapid reaction, and intermittent explosions experienced by these particles have made the gathering of any useful information on burning rates and flame structure very difficult. The use of a reduced gravity environment is needed to clarify some of the complex interactions among the phenomena described above. First, the elimination of the intrusive buoyant flows that plague all combustion phenomena is of paramount importance in metal reactions due to the much higher temperatures reached during combustion. Second, a low-gravity environment is absolutely essential to remove the destructive effect of gravity on the shape of a molten metal droplet in order to study a spherically symmetric condition with large bulk samples. The larger size of the spherical metal droplet and the longer burning times available in reduced gravity extend the spatial and temporal dimensions to permit careful probing of the flame structure and dynamics. Third, the influence of the radiative heat transfer from the solid oxides can be studied more carefully by generating a stagnant spherical shell of condensed products undisturbed by buoyancy.

  6. Making Friends with an Extra-Terrestrial: Conversation Skills and Friendship Formation in Young Children.

    ERIC Educational Resources Information Center

    Parker, Jeffrey G.; Gottman, John M.

    A novel paradigm was developed and two studies conducted to test the contribution of six conversational skills to children's friendship formation. In study 1, 4- and 5-year-olds individually played for 30 minutes with a 2-foot-tall talking doll. The doll contained a wireless hidden receiver/speaker enabling a concealed female assistant to converse

  7. Theoretical Studies of the Extra-terrestrial Chemistry of Biogenic Elements and Compounds

    NASA Technical Reports Server (NTRS)

    Woon, David E.

    2003-01-01

    Results are presented on the following:(A) Ab initio quantum chemical studies of reactions in astrophysical ices.Theoretical electronic structure calculations were used to investigate reactions between formaldehyde (H2CO) and both hydrogen cyanide (HCN) and isocyanide (HNC) in search of other favorable reactions such as ammonia-formaldehyde addition, which was found in a recent theoretical study to be strongly enhanced when it occurs within cold ices.The present study examines further reactions between this product and H2CO in ices.(B) Heterogeneous hydrogenation of CO and H2CO on icy grain mantles.Formaldehyde (H2CO) and methanol (CH30H) are thought to be produced in the interstellar medium by the successive hydrogenation of carbon monoxide (CO) on grain surfaces. In the gas phase, the steps in which H adds to CO and H2CO possess modest barriers and are too inefficient to account for the observed abundances. Recent laboratory work has confirmed that formaldehyde and methanol are formed when H atoms are deposited on CO ice at 12 K. The present study employed ab initio quantum chemical calculations to investigate the impact of water ice on the sequential hydrogenation of CO.(C) Ice-bound condensed-phase reactions involving formic acid (HCOOH), methylenimine (CH2NH), hydrogen cyanide (HCN), hydrogen isocyanide (HNC), and ammonia ( 3) were investigated in order to characterize possible pathways to larger organic species that are efficient at the cold temperatures prevalent in cometary nuclei and the interstellar medium. (D) Pathways to glycine and other amino acids in ultraviolet-irradiated ices determined via quantum chemical modeling.(E) Photoionization in ultraviolet processing of astrophysical ice analogs at cryogenic temperatures.

  8. Genetics Indicates Extra-terrestrial Origins for Life: The First Gene

    NASA Astrophysics Data System (ADS)

    Joseph, Rhawn; Wickramasinghe, N. Chandra

    2011-10-01

    Some of the defining characteristics of life include its ability to replicate and reproduce itself and its genome whilst maintaining a capacity for evolution. Life, as we know it, requires genetic information and no fewer than 382 genes. Thus, the origins of life can be estimated by determining duplication rates beginning with the first gene. Conversely, an approximate date for the origin of the first gene can be estimated based on the time frame in which life appeared on Earth and then evolved. Data from genomics and molecular biology indicate that all modern organisms originated from an ensemble of prokaryotic genes dating back to the first appearance of life on Earth over 4.2 billion years ago (bya), which means life was present on Earth from almost the beginning. There are two main models for the origins of eukaryotes on Earth, "genetic merger" which postulates that eukaryotes evolved between 3 bya to 2 bya following the merger of two species of prokaryote, and "deep roots" which posits that eukaryotes and prokaryotes appeared on Earth at the same time. However, neither model can explain how or when the first genes evolved. To arrive at an estimate for the time frame in which the first gene was fashioned, genetic analysis based on the genetic merger and deep roots models and at different ages for the establishment of life on Earth, were carried out. The correspondence between total gene numbers of various organisms and time of their putative origin over the course of evolutionary history was analysed. Be it the merger or deep roots model, and within the experimental uncertainties in the relevant data, four separate analyses indicates that the origins of the first gene extends backwards in time by an estimated 10 to 14 billion years (10.5<14.5 bya) and thus during a time frame which overlaps and is consistent with estimated ages offered in support of the Big Bang model of the origin of this universe. This does not mean that life began 10-14 billion years ago, but rather that the first gene was fashioned billions of years before the creation of Earth.

  9. Terrestrial Planet Formation in Binary Star Systems

    NASA Technical Reports Server (NTRS)

    Lissauer, J. J.; Quintana, E. V.; Adams, F. C.; Chambers, J. E.

    2006-01-01

    Most stars reside in binary/multiple star systems; however, previous models of planet formation have studied growth of bodies orbiting an isolated single star. Disk material has been observed around one or both components of various young close binary star systems. If planets form at the right places within such disks, they can remain dynamically stable for very long times. We have simulated the late stages of growth of terrestrial planets in both circumbinary disks around 'close' binary star systems with stellar separations ($a_B$) in the range 0.05 AU $\\le a_B \\le$ 0.4 AU and binary eccentricities in the range $0 \\le e \\le 0.8$ and circumstellar disks around individual stars with binary separations of tens of AU. The initial disk of planetary embryos is the same as that used for simulating the late stages of terrestrial planet growth within our Solar System and around individual stars in the Alpha Centauri system (Quintana et al. 2002, A.J., 576, 982); giant planets analogous to Jupiter and Saturn are included if their orbits are stable. The planetary systems formed around close binaries with stellar apastron distances less than or equal to 0.2 AU with small stellar eccentricities are very similar to those formed in the Sun-Jupiter-Saturn, whereas planetary systems formed around binaries with larger maximum separations tend to be sparser, with fewer planets, especially interior to 1 AU. Likewise, when the binary periastron exceeds 10 AU, terrestrial planets can form over essentially the entire range of orbits allowed for single stars with Jupiter-like planets, although fewer terrestrial planets tend to form within high eccentricity binary systems. As the binary periastron decreases, the radial extent of the terrestrial planet systems is reduced accordingly. When the periastron is 5 AU, the formation of Earth-like planets near 1 AU is compromised.

  10. Tidal evolution of extra-solar planets

    NASA Astrophysics Data System (ADS)

    Jackson, Brian Kendall

    In both our solar system and extra-solar planetary systems, tides may have a variety of effects, driving complex orbital evolution and geophysical processes. For extra-solar planets with orbits that pass very close to their host stars, tides have reduced orbital eccentricities and semi-major axes, and the rates of tidal evolution may change dramatically as orbits evolve. Understanding how the orbits have evolved and, ultimately, discerning the origins of close-in extra-solar planets require accounting for all the complexity of tidal evolution. The accompanying dissipation of tidal energy within the planets has probably also affected their internal structures. In some cases, tidal dissipation may account the apparent discrepancy between predictions and observations of the radii of extra-solar planets that transit their host stars. Evolutionary models for these planets that allow determinations of their internal structures and composition must include highly variable tidal heating rates. The same tidal evolution and heating probably also affects the orbital and geophysical properties of rocky extra-solar planets and may play a key role in determining whether such a planet can harbor life. As tides reduce a planet's semi-major axis, the planet may eventually pass so close to its host star that the star's gravity completely disrupts the planet, leading to the destruction of many planets. Tidal destruction has left a discernible signature on the distribution of extra-solar planetary orbits, and so interpretations of the distribution in terms of the origins of planets must include consideration of the effects of tidal destruction.

  11. Solar terrestrial observatory

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Eight basic solar-terrestrial scientific objectives that benefit from the Shuttle/Platform approach and a program of measurements for each are discussed. The objectives are to understand: (1) solar variability, (2) wave-particle processes, (3) magnetosphere-ionosphere mass transport, (4) the global electric circuit, (5) upper atmospheric dynamics, (6) middle atmospheric chemistry and energetics, (7) lower atmospheric turbidity, and (8) planetary atmospheric waves. A two stage approach to a multidisciplinary payload is developed: an initial STO, that uses a single platform in a low-Earth orbit, and an advanced STO that uses two platforms in differing orbits.

  12. Antarctic terrestrial ecosystems

    SciTech Connect

    Walton, D.W.H.

    1987-01-01

    The Maritime and Continental Antarctic terrestrial ecosystems are considered in the context of environmental impacts - habitat destruction, alien introductions, and pollution. Four types of pollution are considered: nutrients, radionuclides, inert materials, and noxious chemicals. Their ability to recover from perturbation is discussed in the light of present scientific knowledge, and the methods used to control impacts are reviewed. It is concluded that techniques of waste disposal are still inadequate, adequate training in environmental and conservation principles for Antarctic personnel in many countries is lacking, and scientific investigations may be a much more serious threat than tourism to the integrity of these ecosystems. Some priorities crucial to future management are suggested.

  13. Solar system constraints on a Rindler-type extra-acceleration from modified gravity at large distances

    SciTech Connect

    Iorio, L.

    2011-05-01

    We analytically work out the orbital effects caused by a Rindler-type extra-acceleration A{sub Rin} which naturally arises in some recent models of modified gravity at large distances. In particular, we focus on the perturbations induced by it on the two-body range ? and range-rate ?-dot which are commonly used in satellite and planetary investigations as primary observable quantities. The constraints obtained for A{sub Rin} by comparing our calculations with the currently available range and range-rate residuals for some of the major bodies of the solar system, obtained without explicitly modeling A{sub Rin}, are 12 10{sup ?13} m s{sup ?2} (Mercury and Venus), 1 10{sup ?14} m s{sup ?2} (Saturn), 1 10{sup ?15} m s{sup ?2} (Mars), while for a terrestrial Rindler acceleration we have an upper bound of 5 10{sup ?16} m s{sup ?2} (Moon). The constraints inferred from the planets' range and range-rate residuals are confirmed also by the latest empirical determinations of the corrections ?dot varpi to the usual Newtonian/Einsteinian secular precessions of the planetary longitudes of perihelia varpi: moreover, the Earth yields A{sub Rin} ? 7 10{sup ?16} m s{sup ?2}. Another approach which could be followed consists of taking into account A{sub Rin} in re-processing all the available data sets with accordingly modified dynamical models, and estimating a dedicated solve-for parameter explicitly accounting for it. Anyway, such a method is time-consuming. A preliminary analysis likely performed in such a way by a different author yields A ? 8 10{sup ?14} m s{sup ?2} at Mars' distance and A ? 1 10{sup ?14} m s{sup ?2} at Saturn's distance. The method adopted here can be easily and straightforwardly extended to other long-range modified models of gravity as well.

  14. Microscopic Primordial Black Holes and Extra Dimensions

    SciTech Connect

    Conley, John A.; Wizansky, Tommer

    2006-11-15

    We examine the production and evolution of microscopic black holes in the early universe in the large extra dimensions scenario. We demonstrate that, unlike in the standard four-dimensional cosmology, in large extra dimensions absorption of matter from the primordial plasma by the black holes is significant and can lead to rapid growth of the black hole mass density. This effect can be used to constrain the conditions present in the very early universe. We demonstrate that this constraint is applicable in regions of parameter space not excluded by existing bounds.

  15. Higgs boson decay constraints on a model with a universal extra dimension

    NASA Astrophysics Data System (ADS)

    Datta, Anindya; Patra, Ayon; Raychaudhuri, Sreerup

    2014-05-01

    We investigate the impact of the latest data on Higgs boson branching ratios on the minimal model with a universal extra dimension. Combining constraints from vacuum stability requirements with these branching ratio measurements we are able to make realistic predictions for the signal strengths in this model. We use these to find a lower bound of 1.3 TeV on the size parameter R-1 of the model at 95% confidence level, which is far more stringent than any other terrestrial bound obtained till now and is compatible with the dark matter constraints from the Wilkinson Microwave Anisotropy Probe data.

  16. Solar structure and terrestrial weather

    NASA Technical Reports Server (NTRS)

    Wilcox, J. M.

    1976-01-01

    The possibility that solar activity has discernible effects on terrestrial weather is considered. Research involving correlation of weather conditions with solar and geomagnetic activity is discussed.

  17. Progress in extra-solar planet detection

    NASA Technical Reports Server (NTRS)

    Brown, Robert A.

    1991-01-01

    Progress in extra-solar planet detection is reviewed. The following subject areas are covered: (1) the definition of a planet; (2) the weakness of planet signals; (3) direct techniques - imaging and spectral detection; and (4) indirect techniques - reflex motion and occultations.

  18. Terrestrial Planet Growth in Circumbinary Disks

    NASA Technical Reports Server (NTRS)

    Lissauer, J. J.; Quintana, E. V.

    2006-01-01

    We examine the accuulation of terrestrial from circumbinary disks surrounding pairs of stars with masses of either 0.5 solar masses each or 0.8 and 0.2 solar masses and orbital separations of 0.05 AU to 0.4 AU by performing numerical simulations of the late stages of planetary growth. Initial disks contain about 2.6 Earth masses of lunar to Mars-sized bodies orbiting within 2 AU of the center of mass of the system, plus giant planets with masses and orbits analogous to those of Jupiter and Saturn. We also performed simulations using analogous disks orbiting single 1 solar mass stars. The dynamics of planetary growth is quite chaotic because the gravitational perturbations resulting from close approaches greatly amplify differences in orbits. Thus, several simulations of each configuration were run with very slightly different initial conditions to enable us to distinguish systematic effects resulting from differences in the binary orbit (or differences of the initial orbits of the bodies within the disk) from pseudo-random variability in outcomes resulting from chaos. Most runs simulated 200 million years of evolution. At least one terrestrial planet remained at the end of each run; one simulation produced 6 terrestrial planets in a configuration that appears to be quite stable. The systems that formed around stars with binary apastron separations of less than 0.2 AU contained on average slightly more planets than those that formed around single stars, with the outermost planet typically orbiting at a greater distance from the system barycenter. Greater stellar separations tended to result in fewer planets, with the inner planet orbiting farther from the stars. More eccentric binaries have a more pronounced effect for the same apastron distance. The statistical distribution of final systems is not sensitive to moderate differences in the initial eccentricities of the bodies in the disk.

  19. Terrestrial Planet Geophysics

    NASA Astrophysics Data System (ADS)

    Phillips, R. J.

    2008-12-01

    Terrestrial planet geophysics beyond our home sphere had its start arguably in the early 1960s, with Keith Runcorn contending that the second-degree shape of the Moon is due to convection and Mariner 2 flying past Venus and detecting no planetary magnetic field. Within a decade, in situ surface geophysical measurements were carried out on the Moon with the Apollo program, portions of the lunar magnetic and gravity fields were mapped, and Jack Lorell and his colleagues at JPL were producing spherical harmonic gravity field models for Mars using tracking data from Mariner 9, the first spacecraft to orbit another planet. Moreover, Mariner 10 discovered a planetary magnetic field at Mercury, and a young Sean Solomon was using geological evidence of surface contraction to constrain the thermal evolution of the innermost planet. In situ geophysical experiments (such as seismic networks) were essentially never carried out after Apollo, although they were sometimes planned just beyond the believability horizon in planetary mission queues. Over the last three decades, the discipline of terrestrial planet geophysics has matured, making the most out of orbital magnetic and gravity field data, altimetric measurements of surface topography, and the integration of geochemical information. Powerful constraints are provided by tectonic and volcanic information gleaned from surface images, and the engagement of geologists in geophysical exercises is actually quite useful. Accompanying these endeavors, modeling techniques, largely adopted from the Earth Science community, have become increasingly sophisticated and have been greatly enhanced by the dramatic increase in computing power over the last two decades. The future looks bright with exciting new data sets emerging from the MESSENGER mission to Mercury, the promise of the GRAIL gravity mission to the Moon, and the re-emergence of Venus as a worthy target for exploration. Who knows? With the unflagging optimism and persistence of a few diehards, we may eventually have a seismic and heat flow network on Mars.

  20. Terrestrial Impack Cratering Chronology : A Preliminary Analysis

    NASA Astrophysics Data System (ADS)

    Moon, Hong-Kyu; Min, Byung-Hee; Fletcher, Andr B.; Kim, Bong-Gyu; Han, Won-Yong; Chun, Moo-Young; Jeon, Young-Beom; Lee, Woo-Baik

    2001-12-01

    We have recently compiled a database of the properties of 192 impact craters, which supercedes previous compilations. Using our database, the impact structures found in North America, Europe and Australia have been examined; these cratonic areas have been relatively stable for considerably long geological periods, and thus have been best preserved. It is confirmed that there is a close correlation between the geological epoch boundaries, the epochs of mass extinctions, and the ``timing'' of impacts. In addition, the terrestrial cumulative flux of objects >20km is found to be 1.7710-15km-2yr-1, over the last 120 Myr, which is much smaller than the published values in McEwen et al. (1997) and Shoemaker (1998) (5.62.810-15km-2yr-1). For terrestrial impact structures with D>50 km, the apparent cumulative flux over the last 2450 Myr is ~50 times smaller than the corresponding value for the Moon. If we assume that the Earth and the Moon suffered the same level of bombardment over this time, this would mean that the actual flux of impacting bodies, capable of making craters with D>50 km, was ~ 50 times larger than the apparent flux estimated from the currently known terrestrial records.

  1. Terrestrialization, miniaturization and rates of diversification in African frogs (Anura: Phrynobatrachidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Terrestrialization, the evolution of non-aquatic oviposition, and miniaturization, the evolution of tiny adult body size, have been identified as a key features in the evolution of modern amphibians. This study examines anuran terrestrialization and miniaturization in a phylogenetic context to deter...

  2. Numerical simulation of the final stages of terrestrial planet formation

    NASA Technical Reports Server (NTRS)

    Cox, L. P.; Lewis, J. S.

    1980-01-01

    Three representative numerical simulations of the growth of the terrestrial planets by accretion of large protoplanets are considered. The mass and relative-velocity distributions of the bodies are free to evolve simultaneously in response to close gravitational encounters and occasional collisions between bodies. The collisions between bodies arise therefore in a natural way and the assumption of expressions for the relative-velocity distribution and the gravitational collision cross section is unnecessary. These simulations indicate that the growth of bodies with final masses approaching those of Venus and earth is possible, at least for the case of a two-dimensional system

  3. Thermoacoustic dosimetry of electron beam in extra field

    SciTech Connect

    Kalinichenko, A.I.; Kresnin, Yu.A.; Popov, G.F.

    1996-12-31

    The theoretical basis is elaborated for thermoacoustic dosimetry of electron beam by one-dimensional (1-D) thin target TT in extra thermal and electromagnetic fields. The basic equation joining the deposited energy distribution to the stress wave amplitude in the case when the generation coefficient is function of temperature and coordinate in material permits realizing nonlinear thermoacoustic dosimetry with regulated sensitivity. Some variants of joint employment of the thermoacoustic dosimeter and electromagnetic scanner/splitter are considered. The first variant consists in beam scanning along 1-D dosimeter body to create the moving thermoacoustic source. This regime may be used for dosimetry of long beams. The second variant consists in spectral decomposition of the beam in electromagnetic field before its directing to the dosimeter. Principle of operation for some termoelastic dosimeters on the base of 1-D TTs is considered.

  4. Does Terrestrial Carbon Subsidize Production of Estuarine Fish Larvae?

    EPA Science Inventory

    The study shows important connections between terrestrial, riverine and marine energy sources in supporting larval fish production across an estuarine ecosystem in Chesapeake Bay, VA. It adds to a growing body of evidence that across ecosystem energy-exchanges play an important ...

  5. Brane modeling in warped extra-dimension

    NASA Astrophysics Data System (ADS)

    Ahmed, Aqeel; Grzadkowski, Bohdan

    2013-01-01

    Five-dimensional scenarios with infinitesimally thin branes replaced by appropriate configurations of a scalar field were considered. A possibility of periodic extra dimension was discussed in the presence on non-minimal scalar-gravity coupling and a generalized Gibbons-Kallosh-Linde sum rule was found. In order to avoid constraints imposed by periodicity, a non-compact spacial extra dimension was introduced. A five dimensional model with warped geometry and two thin branes mimicked by a scalar profile was constructed and discussed. In the thin brane limit the model corresponds to a set-up with two positive-tension branes. The presence of two branes allows to address the issue of the hierarchy problem which could be solved by the standard warping of the four dimensional metric provided the Higgs field is properly localized. Stability of the background solution was discussed and verified in the presence of the most general perturbations of the metric and the scalar field.

  6. Dimensional reduction without continuous extra dimensions

    SciTech Connect

    Chamseddine, Ali H.; Froehlich, J.; Schubnel, B.; Wyler, D.

    2013-01-15

    We describe a novel approach to dimensional reduction in classical field theory. Inspired by ideas from noncommutative geometry, we introduce extended algebras of differential forms over space-time, generalized exterior derivatives, and generalized connections associated with the 'geometry' of space-times with discrete extra dimensions. We apply our formalism to theories of gauge- and gravitational fields and find natural geometrical origins for an axion- and a dilaton field, as well as a Higgs field.

  7. Kinks, extra dimensions, and gravitational waves

    SciTech Connect

    O'Callaghan, Eimear; Gregory, Ruth

    2011-03-01

    We investigate in detail the gravitational wave signal from kinks on cosmic (super)strings, including the kinematical effects from the internal extra dimensions. We find that the signal is suppressed, however, the effect is less significant that that for cusps. Combined with the greater incidence of kinks on (super)strings, it is likely that the kink signal offers the better chance for detection of cosmic (super)strings.

  8. Primitive Terrestrial Atmospheres

    NASA Astrophysics Data System (ADS)

    Zahnle, Kevin John

    1985-12-01

    A 23.3 year periodicity preserved in a 2500 million year old banded iron-formation is interpreted as reflecting the climatic influence of the lunar nodal tide, the signature of which has been detected in the modern climate. The lunar distance is deduced to have been 52 Earth radii. The influence of the lunar nodal tide is also detected in varves dating to 680 million years B.P. The implied history of Precambrian tidal friction is in excellent agreement with both more recent paleontological evidence and the long -term stability of the lunar orbit. The solar semidiurnal thermal tide was resonant with the natural period of the atmosphere when the day was (TURN)21.3 hours. This took place at the end of the Precambrian. The resonant atmospheric tide would have been large enough (.01 bar at the surface) to have influenced the weather. In contrast to lunar oceanic tides, the gravitational torque on the thermal tide accelerates the Earth's rotation rate; near resonance the opposing torques were comparable, so that the day may have been stabilized near 21.3 hours for much of the Precambrian. A sustained resonance does not conflict with the available evidence. Methane photochemistry in the primitive terrestrial atmosphere is studied using a detailed numerical model. Methane is oxidized cleanly and efficiently provided CO(,2) is more abundant than CH(,4). If CH(,4) and CO(,2) abundances are comparable, a large fraction of the methane present is polymerized, forming alkanes in the troposphere and polyacetylenes and nitriles in the upper atmosphere. Production of HCN from CH(,4) and N(,2) in the anaerobic atmosphere and its subsequent removal in rainwater could have been efficient; net production varying from .01% to 10% of the methane consumed. In the absence of a magnetic field, high ancient solar EUV and X-ray fluxes would have permitted an ocean of hydrogen to escape as a transsonic wind from a primordial accretionary greenhouse atmosphere in as little as 25 million years. The terrestrial magnetic field would have been strong enough to have prevented a freely flowing wind, reducing escape by one or two orders of magnitude with respect to an otherwise identical Venus.

  9. Noncommutative Inspired Black Holes in Extra Dimensions

    SciTech Connect

    Rizzo, Thomas G.

    2006-06-07

    In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS assumed that this smearing was essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from {approx} 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the TeV-scale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We also demonstrate that the essential features of this approach are not particularly sensitive to the Gaussian nature of the smearing assumed by NSS.

  10. Elliptical instability in terrestrial planets and moons

    NASA Astrophysics Data System (ADS)

    Cebron, D.; Le Bars, M.; Moutou, C.; Le Gal, P.; Maubert, P.

    2011-10-01

    Any planet may be subject to three kinds of harmonic mechanical forcing, driven respectively by libration, precession and tides. These forcings can generate flows in internal fluid layers such as fluid cores and subsurface oceans, whose dynamics then significantly differ from solid body rotation. In particular, tides and librations are known to be capable of exciting the so-called elliptical instability, corresponding to the destabilization of two-dimensional flows with elliptical streamlines, leading to three-dimensional turbulence. The presence of such an elliptical instability driven by tides and librations is investigated in terrestrial bodies. Its consequences on energy dissipation, on magnetic field induction and on heat flux fluctuations at the planetary scale are considered.

  11. 19 CFR 151.64 - Extra copy of entry summary.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Wool and Hair § 151.64 Extra copy of entry summary. One extra copy of the entry summary covering wool or hair subject to duty at a rate...

  12. 19 CFR 151.64 - Extra copy of entry summary.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Wool and Hair § 151.64 Extra copy of entry summary. One extra copy of the entry summary covering wool or hair subject to duty at a rate...

  13. 19 CFR 151.64 - Extra copy of entry summary.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Wool and Hair § 151.64 Extra copy of entry summary. One extra copy of the entry summary covering wool or hair subject to duty at a rate...

  14. 19 CFR 151.64 - Extra copy of entry summary.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Wool and Hair § 151.64 Extra copy of entry summary. One extra copy of the entry summary covering wool or hair subject to duty at a rate...

  15. 19 CFR 151.64 - Extra copy of entry summary.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Wool and Hair § 151.64 Extra copy of entry summary. One extra copy of the entry summary covering wool or hair subject to duty at a rate...

  16. Utility terrestrial biodiversity issues

    SciTech Connect

    Breece, G.A.; Ward, B.J.

    1996-11-01

    Results from a survey of power utility biologists indicate that terrestrial biodiversity is considered a major issued by only a few utilities; however, a majority believe it may be a future issue. Over half of the respondents indicated that their company is involved in some management for biodiversity, and nearly all feel that it should be a goal for resource management. Only a few utilities are funding biodiversity research, but a majority felt more research was needed. Generally, larger utilities with extensive land holdings had greater opportunities and resources for biodiversity management. Biodiversity will most likely be a concern with transmission rights-of-way construction and maintenance, endangered species issues and general land resource management, including mining reclamation and hydro relicensing commitments. Over half of the companies surveyed have established voluntary partnerships with management groups, and biodiversity is a goal in nearly all the joint projects. Endangered species management and protection, prevention of forest fragmentation, wetland protection, and habitat creation and protection are the most common partnerships involving utility companies. Common management practices and unique approaches are presented, along with details of the survey. 4 refs.

  17. Space or terrestrial energy?

    NASA Astrophysics Data System (ADS)

    Boulet, L.

    Consideration is given to the possibility of generating sufficient energy at acceptable costs on earth to offset the need to build solar power satellite systems (SPS). Electricity usage, one of the basic driving forces of developed nations, grows with the population. Currently comprising 33 pct of the total world energy used, electricity is projected to grow to a 50-55 pct share in the 21st century. Future terrestrial electrical energy sources include carbon-based fuels, nuclear (fusion or fission), and the renewable solar technologies. Carbon-based fuel supplies can last until 2030 AD, about the same as fission plants with recycled fuel. Breeder reactors would stretch the nuclear fuels to the year 3000. Solar technologies offer more immediate solutions than fusion reactors and can produce 50 pct of the power available from the construction of the maximum number of nuclear power plants. The addition of SPS would further augment the total. Combinations of all the technologies are recommended, with local research for the most appropriate technology for each nation.

  18. 7 CFR 51.300 - U.S. Extra Fancy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. Extra Fancy. 51.300 Section 51.300 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Apples Grades § 51.300 U.S. Extra Fancy. “U.S. Extra Fancy” consists of apples...

  19. Coupling Between Terrestrial and Giant Planets During Migration

    NASA Astrophysics Data System (ADS)

    Agnor, C.

    2005-08-01

    The timescales for the formation of Uranus and Neptune (106-10^9 yr) and the subsequent migration of all the outer planets (a few 107- 108 yr) overlap with the the formation timescale of the terrestrial planets (20-200 Myr based on isotopic data and accretion simulations). It has also been suggested that the late formation and/or migration of the giant planets may have triggered the Late Heavy Bombardment of the Moon 700 Myr after the terrestrial planets formed (e.g. Levison et al. 2001, Gomes et al. 2005). How would the gross changes in the dynamical structure of the migrating giant planets affect the inner terrestrial planets? Changes in the orbital elements of the outer planets alter the amplitudes and characteristic frequencies of their perturbations on the rest of the planetary system. Thus, the migration of the giant planets after terrestrial planet formation could result in strong external forcing of the inner solar system. The emphasis of this study is two-fold: 1) to use the dynamical state of the terrestrial planets to constrain the timing and/or conditions of giant planet migration, and 2) to explore the specific effects of giant planet migration on the inner solar system. I have performed numerical N-body integrations that address how the late migration of the giant planets alters the dynamical state of the inner solar system. These integrations include the four migrating giant planets, the fully formed terrestrial planets and are performed using the Symba integrator (Duncan et al. 1998). The initial results indicate that the migration of Jupiter, Saturn, Uranus and Neptune can result in strong dynamical coupling with the terrestrial planets. The gross effects of this coupling include destabilization of the terrestrial system, additional planetary collisions, and the excitation of Mercury and Mars to more eccentric orbits.

  20. Radiocarbon dating of terrestrial carbonates

    USGS Publications Warehouse

    Pigati, Jeffrey S.

    2014-01-01

    Terrestrial carbonates encompass a wide range of materials that potentially could be used for radiocarbon (14C) dating. Biogenic carbonates, including shells and tests of terrestrial and aquatic gastropods, bivalves, ostracodes, and foraminifera, are preserved in a variety of late Quaternary deposits and may be suitable for 14C dating. Primary calcareous deposits (marls, tufa, speleothems) and secondary carbonates (rhizoliths, fracture fill, soil carbonate) may also be targeted for dating when conditions are favorable. This chapter discusses issues that are commonly encountered in 14C dating of terrestrial carbonates, including isotopic disequilibrium and open-system behavior, as well as methods used to determine the reliability of ages derived from these materials. Recent methodological advancements that may improve the accuracy and precision of 14C ages of terrestrial carbonates are also highlighted.

  1. Contaminant Exposure in Terrestrial Vertebrates

    EPA Science Inventory

    Manuscript is a critical review of the state of the science for quantifying exposures of terrestrial wildlife species to chemical contamination. It describes the unique aspects of birds, mammals, reptiles, amphibians and threatened and endangered species. Fate and transport of ...

  2. USING TERRESTRIAL PLANTS IN BIOMONITORING

    EPA Science Inventory

    Terrestrial plants have been used as monitors of environmental pollutants since at least the beginning of this century & have recently received attention in response to the need for ecological assessments at hazardous waste sites & monitoring pesticide damage to nontarget plants....

  3. Planetary habitability: lessons learned from terrestrial analogues

    NASA Astrophysics Data System (ADS)

    Preston, Louisa J.; Dartnell, Lewis R.

    2014-01-01

    Terrestrial analogue studies underpin almost all planetary missions and their use is essential in the exploration of our Solar system and in assessing the habitability of other worlds. Their value relies on the similarity of the analogue to its target, either in terms of their mineralogical or geochemical context, or current physical or chemical environmental conditions. Such analogue sites offer critical ground-truthing for astrobiological studies on the habitability of different environmental parameter sets, the biological mechanisms for survival in extreme environments and the preservation potential and detectability of biosignatures. The 33 analogue sites discussed in this review have been selected on the basis of their congruence to particular extraterrestrial locations. Terrestrial field sites that have been used most often in the literature, as well as some lesser known ones which require greater study, are incorporated to inform on the astrobiological potential of Venus, Mars, Europa, Enceladus and Titan. For example, the possibility of an aerial habitable zone on Venus has been hypothesized based on studies of life at high-altitudes in the terrestrial atmosphere. We also demonstrate why many different terrestrial analogue sites are required to satisfactorily assess the habitability of the changing environmental conditions throughout Martian history, and recommend particular sites for different epochs or potential niches. Finally, habitable zones within the aqueous environments of the icy moons of Europa and Enceladus and potentially in the hydrocarbon lakes of Titan are discussed and suitable analogue sites proposed. It is clear from this review that a number of terrestrial analogue sites can be applied to multiple planetary bodies, thereby increasing their value for astrobiological exploration. For each analogue site considered here, we summarize the pertinent physiochemical environmental features they offer and critically assess the fidelity with which they emulate their intended target locale. We also outline key issues associated with the existing documentation of analogue research and the constraints this has on the efficiency of discoveries in this field. This review thus highlights the need for a global open access database for planetary analogues.

  4. Unraveling the chemical space of terrestrial and meteoritic organic matter

    NASA Astrophysics Data System (ADS)

    Schmitt-Kopplin, Philippe; Harir, Mourad; Hertkorn, Norbert; Kanawati, Basem; Ruf, Alexander; Quirico, Eric; Bonal, Lydie; Beck, Pierre; Gabelica, Zelimir

    2015-04-01

    In terrestrial environments natural organic matter (NOM) occurs in soils, freshwater and marine environments, in the atmosphere and represents an exceedingly complex mixture of organic compounds that collectively exhibits a nearly continuous range of properties (size-reactivity continuum). In these materials, the "classical" biogeosignatures of the (biogenic and geogenic) precursor molecules, like lipids, lignins, proteins and natural products have been attenuated, often beyond recognition, during a succession of biotic and abiotic (e.g. photo- and redox chemistry) reactions. Because of this loss of biochemical signature, these materials can be designated non-repetitive complex systems. The access to extra-terrestrial organic matter is given i.e. in the analysis of meteoritic materials. Numerous descriptions of organic molecules present in organic chondrites have improved our understanding of the early interstellar chemistry that operated at or just before the birth of our solar system. However, many molecular analyses are so far targeted toward selected classes of compounds with a particular emphasis on biologically active components in the context of prebiotic chemistry. Here we demonstrate that a non-targeted ultrahigh-resolution molecular analysis of the solvent-accessible organic fraction of meteorite extracted under mild conditions allows one to extend its indigenous chemical diversity to tens of thousands of different molecular compositions and likely millions of diverse structures. The description of the molecular complexity provides hints on heteroatoms chronological assembly, shock and thermal events and revealed recently new classes of thousands of novel organic, organometallic compounds uniquely found in extra-terrestrial materials and never described in terrestrial systems. This high polymolecularity suggests that the extraterrestrial chemodiversity is high compared to terrestrial relevant biological and biogeochemical-driven chemical space. (ultra)High resolution analytical approaches will be presented in their application to unravel the chemical nature and organic signatures in bio-geosystems and especially in selected chondritic (organic and ordinary) and achondritic meteorites. We will focus on thermal effects in CM types of materials and describe the effect of shock events on the changes in chemodiversity and the formation of unique novel organic compounds using high magnetic field ultrahigh resolution mass spectrometry (12 Tesla ion cyclotron resonance Fourier transform mass spectrometry - ICR-FT/MS) and nuclear magnetic resonance spectroscopy (Cryo 800MHz NMR).

  5. Sustained periodic terrestrial locomotion in air-breathing fishes.

    PubMed

    Pace, C M; Gibb, A C

    2014-03-01

    While emergent behaviours have long been reported for air-breathing osteichthyians, only recently have researchers undertaken quantitative analyses of terrestrial locomotion. This review summarizes studies of sustained periodic terrestrial movements by air-breathing fishes and quantifies the contributions of the paired appendages and the axial body to forward propulsion. Elongate fishes with axial-based locomotion, e.g. the ropefish Erpetoichthys calabaricus, generate an anterior-to-posterior wave of undulation that travels down the axial musculoskeletal system and pushes the body against the substratum at multiple points. In contrast, appendage-based locomotors, e.g. the barred mudskipper Periophthalmus argentilineatus, produce no axial bending during sustained locomotion, but instead use repeated protraction-retraction cycles of the pectoral fins to elevate the centre of mass and propel the entire body anteriorly. Fishes that use an axial-appendage-based mechanism, e.g. walking catfishes Clarias spp., produce side-to-side, whole-body bending in co-ordination with protraction-retraction cycles of the pectoral fins. Once the body is maximally bent to one side, the tail is pressed against the substratum and drawn back through the mid-sagittal plane, which elevates the centre of mass and rotates it about a fulcrum formed by the pectoral fin and the ground. Although appendage-based terrestrial locomotion appears to be rare in osteichthyians, many different species appear to have converged upon functionally similar axial-based and axial-appendage-based movements. Based on common forms observed across divergent taxa, it appears that dorsoventral compression of the body, elongation of the axial skeleton or the presence of robust pectoral fins can facilitate effective terrestrial movement by air-breathing fishes. PMID:24502775

  6. Large Extra Dimension and Dark Matter Detection

    NASA Astrophysics Data System (ADS)

    Qin, Bo; Starkman, Glenn D.; Silk, Joseph

    2008-01-01

    If our space has the large extra dimensions as proposed by Arkani-Hamed, Dimopoulos and Dvali (ADD), then gravity would start to deviate from Newtonian gravity and be greatly enhanced in sub-millimeter scales. Here we show that in the ADD scenario, gravity could play an important role (compared to the weak interaction) in the interactions between dark matter particles and the electron. We find that for typical WIMP dark matter, such dark matter-electron ``gravitational'' scattering cross section may be much larger than the dark matter-nucleon cross section constrained by current dark matter experiments.

  7. Direct imaging of extra-solar planets

    SciTech Connect

    Olivier, S.S.; Max, V.E.; Brase, J.M.; Caffano, C.J.; Gavel, D.T.; Macintosh, B.A.

    1997-03-01

    Direct imaging of extra-solar planets may be possible with the new generation of large ground-based telescopes equipped with state- of- the-art adaptive optics (AO) systems to compensate for the blurring effect of the Earth`s atmosphere. The first of these systems is scheduled to begin operation in 1998 on the 10 in Keck II telescope. In this paper, general formulas for high-contrast imaging with AO systems are presented and used to calculate the sensitivity of the Keck AO system. The results of these calculations show that the Keck AO system should achieve the sensitivity necessary to detect giant planets around several nearby bright stars.

  8. The EXTraS project: Exploring the X-ray Transient and variable Sky

    NASA Astrophysics Data System (ADS)

    De Luca, Andrea; EXTraS Collaboration

    2015-09-01

    EXTraS (EU-FP7 framework) is the first systematic search for (and characterization of) all variable soft X-ray sources at all time scales in the whole archive of observations collected by the EPIC instrument on-board XMM-Newton since its launch in 1999, looking for transients, aperiodic, periodic and long-term variability. The project includes the phenomenological classification of all detected variable sources, extending and improving the 3XMM catalalogue. All results will be released in a public archive, together with new software tools.

  9. Extra-pancreatic effects of incretin-based therapies.

    PubMed

    Gallwitz, Baptist

    2014-11-01

    Glucagon-like peptide-1 (GLP-1) stimulates insulin secretion and inhibits glucagon secretion in the pancreatic islets of Langerhans under hyperglycaemia. In type 2 diabetes (T2DM), GLP-1 improves glycaemic control without a hypoglycaemia risk. GLP-1 receptors have also been found in extra-pancreatic tissues, e.g., the cardiovascular system, the gastrointestinal system, and the central nervous system. Since cardiovascular comorbidities and degenerative neurological changes are associated with T2DM, the interest in the extrapancreatic effects of GLP-1 has increased. GLP-1-based therapies with either GLP-1 receptor agonists (GLP-1 RA) or DPP-4 inhibitors (that delay the degradation of endogenous GLP-1) have become widely used therapeutic options in T2DM. In clinical studies, GLP-1 RA have demonstrated a significant lowering of blood pressure that is independent of body weight changes. Preclinical data and small short-term studies with GLP-1 and GLP-1 RA have shown cardioprotective effects in ischaemia models. GLP-1 as well as a treatment with GLP-1 RA also induces a stable body weight loss by affecting GLP-1 signaling in the hypothalamus and by slowing gastric emptying. Regarding neuroprotective actions in degenerative neurological disease models for Parkinson's- or Alzheimer's disease or neurovascular complications like stroke, animal studies have shown positive results. In this article, a summary of the extrapancreatic effects of GLP-1 and GLP-1-based therapies is presented. PMID:24604239

  10. Robust frameless stereotactic localization in extra-cranial radiotherapy

    SciTech Connect

    Riboldi, Marco; Baroni, Guido; Spadea, Maria Francesca; Bassanini, Fabio; Tagaste, Barbara; Garibaldi, Cristina; Orecchia, Roberto; Pedotti, Antonio

    2006-04-15

    In the field of extra-cranial radiotherapy, several inaccuracies can make the application of frameless stereotactic localization techniques error-prone. When optical tracking systems based on surface fiducials are used, inter- and intra-fractional uncertainties in marker three-dimensional (3D) detection may lead to inexact tumor position estimation, resulting in erroneous patient setup. This is due to the fact that external fiducials misdetection results in deformation effects that are poorly handled in a rigid-body approach. In this work, the performance of two frameless stereotactic localization algorithms for 3D tumor position reconstruction in extra-cranial radiotherapy has been specifically tested. Two strategies, unweighted versus weighted, for stereotactic tumor localization were examined by exploiting data coming from 46 patients treated for extra-cranial lesions. Measured isocenter displacements and rotations were combined to define isocentric procedures, featuring 6 degrees of freedom, for correcting patient alignment (isocentric positioning correction). The sensitivity of the algorithms to uncertainties in the 3D localization of fiducials was investigated by means of 184 numerical simulations. The performance of the implemented isocentric positioning correction was compared to conventional point-based registration. The isocentric positioning correction algorithm was tested on a clinical dataset of inter-fractional and intra-fractional setup errors, which was collected by means of an optical tracker on the same group of patients. The weighted strategy exhibited a lower sensitivity to fiducial localization errors in simulated misalignments than those of the unweighted strategy. Isocenter 3D displacements provided by the weighted strategy were consistently smaller than those featured by the unweighted strategy. The peak decrease in median and quartile values of isocenter 3D displacements were 1.4 and 2.7 mm, respectively. Concerning clinical data, the weighted strategy isocentric positioning correction provided the reduction of fiducial registration errors, featuring up to 61.7% decrease in median values (versus 46.8% for the unweighted strategy) of initial displacements. The weighted strategy proved high performance in minimizing the effects of fiducial localization errors, showing a great potential in improving patient setup. The clinical data analysis revealed that the application of a robust reconstruction algorithm may provide high-quality results in patient setup verification, by properly managing external fiducials localization errors.

  11. Flavor Structure of Warped Extra Dimension Models

    SciTech Connect

    Agashe, Kaustubh; Perez, Gilad; Soni, Amarjit

    2004-08-10

    We recently showed, in hep-ph/0406101, that warped extra dimensional models with bulk custodial symmetry and few TeV KK masses lead to striking signals at B-factories. In this paper, using a spurion analysis, we systematically study the flavor structure of models that belong to the above class. In particular we find that the profiles of the zero modes, which are similar in all these models, essentially control the underlying flavor structure. This implies that our results are robust and model independent in this class of models. We discuss in detail the origin of the signals in B-physics. We also briefly study other NP signatures that arise in rare K decays (K {yields} {pi}{nu}{nu}), in rare top decays [t {yields} c{gamma}(Z, gluon)] and the possibility of CP asymmetries in D{sup 0} decays to CP eigenstates such as K{sub s}{pi}{sup 0} and others. Finally we demonstrate that with light KK masses, {approx} 3 TeV, the above class of models with anarchic 5D Yukawas has a ''CP problem'' since contributions to the neutron electric dipole moment are roughly 20 times larger than the current experimental bound. Using AdS/CFT correspondence, these extra-dimensional models are dual to a purely 4D strongly coupled conformal Higgs sector thus enhancing their appeal.

  12. Search for extra-solar planets

    NASA Astrophysics Data System (ADS)

    Skuljan, J.

    2003-10-01

    A number of different observational techniques are used today for the detection of planets beyond our solar system. Most of them are indirect methods, based on dynamical or photometric effects induced by the planet and measured on the parent star. The most successful technique so far has been the Doppler (radial-velocity) method, based on precise measurements of small variations in the radial velocity of the parent star. About one hundred extra-solar planets have been discovered by this technique. Other methods are based on astrometric measurements, direct imaging, photometry, interferometry and gravitational microlensing. Some of these techniques are already able to produce positive results, but many of them are future projects needing more advanced instrumentation. In this paper the most important techniques for extra-solar planet detection will be reviewed and their results summarized. In the second part, two different projects carried out at Mt John University Observatory, Lake Tekapo, New Zealand will be presented, both involved in planet hunting. One is the HERCULES radial-velocity programme and the other is the MOA microlensing project.

  13. The Extra-Zodiacal Explorer (EZE)

    NASA Astrophysics Data System (ADS)

    Greenhouse, Matthew A.; Benson, S. W.; Fixsen, D. J.; Gardner, J. P.; Kruk, J. W.; Thronson, H. A.

    2012-01-01

    We describe a mission architecture study designed to substantially increase the potential science performance of the NASA SMD Astrophysics Explorer Program for all AO offerors working within the near-UV to far-infrared spectrum. We have demonstrated that augmentation of Falcon 9 Explorer launch services with a Solar Electric Propulsion (SEP) stage can deliver a 700 kg science observatory payload to an extra-Zodiacal orbit. This new capability enables up to 10X increased photometric sensitivity and 150X increased observing speed relative to a Sun-Earth L2 or Earth-trailing orbit with no increase in telescope aperture. All enabling SEP stage technologies for this launch service augmentation have reached sufficient readiness (TRL-6) for Explorer Program application in conjunction with the Falcon 9. We demonstrate that enabling Astrophysics Explorers to reach extra-zodiacal orbit will allow this small payload program to rival the science performance of much larger long development time systems; thus, providing a means to realize major science objectives while increasing the SMD Astrophysics portfolio diversity and resiliency to external budget pressure. The SEP technology employed in this study has applicability to SMD Planetary competed missions and aligns with NASA in-space propulsion technology road map objectives and associated flight demonstration planning.

  14. Fish out of water: terrestrial jumping by fully aquatic fishes.

    PubMed

    Gibb, Alice C; Ashley-Ross, Miriam A; Pace, Cinnamon M; Long, John H

    2011-12-01

    Many teleosts that live at the water's edge will voluntarily strand themselves to evade predators or escape poor conditions-this behavior has been repeatedly observed in the field for killifishes (Cyprinodontiformes). Although most killifishes are considered fully aquatic and possess no obvious morphological specializations to facilitate terrestrial locomotion, individuals from several different species have been observed moving across land via a "tail flip" behavior that generates a terrestrial jump. Like aquatic fast starts, terrestrial jumps are produced by high-curvature lateral flexion of the body (stage one), followed by contralateral flexion of the posterior body (stage two). Here, terrestrial jumps and aquatic fast starts are quantified for two littoral teleosts: Gambusia affinis (a killifish, Cyprinodontiformes) and Danio rerio (a small carp, Cypriniformes) to determine if the tail flip is produced by other (non-killifish) teleosts and to test the null hypothesis that the tail flip is a fast start behavior, performed on land. Both Danio and Gambusia produce tail flip-driven terrestrial jumps, which are kinematically distinct from aquatic escapes and characterized by (1) a prolonged stage one, during which the fish bends, lifting and rolling the center of mass over the caudal peduncle, and (2) a relatively brief stage two, wherein the caudal peduncle pushes against the substrate to launch the fish into the aerial phase. The ability of these fully aquatic fishes to employ the same structure to produce distinct kinematic patterns in disparate environments suggests that a new behavior has evolved to facilitate movement on land and that anatomical novelty is not a prerequisite for effective terrestrial locomotion. PMID:21972177

  15. The EXTraS project: Exploring the X-ray Transient and variable Sky

    NASA Astrophysics Data System (ADS)

    Kreikenbohm, A.; Oertel, M.; Wilms, J.; DeLuca, A.; Haberl, F.; Greiner, J.; Delvaux, C.; Carpano, S.; Law-Green, D.; Rosen, S.

    2015-07-01

    Modern X-ray observatories can yield unique insights into time domain astrophysics. Indeed, a huge amount of information is already stored - and largely unexploited - in data archives. The EXTraS project harvests the hitherto unexplored temporal domain information buried in the serendipitous data collected by the European Photon Imaging Camera (EPIC) instrument onboard the ESA XMM-Newton mission since its launch. This includes a search for fast transients, missed by standard image analysis, and a search and characterization of variability (both periodic and aperiodic) in hundreds of thousands of sources spanning more than nine orders of magnitude in time scale (from less than 1 s to 10 yr) and six orders of magnitude in flux (from 10(-9) to more than 10(-15) erg cm(-2) s(-1) in 0.2-12 keV). X-ray results are to be complemented by multiwavelength characterization of new discoveries. Phenomenological classification of variable sources will also be performed. Our final catalogue and results will be made available to the community, together with new analysis tools, at the end of the project (late 2016). EXTraS is funded within the EU/FP7-Cooperation Space framework and is carried out by a collaboration including INAF (Italy), IUSS (Italy), CNR/IMATI (Italy), University of Leicester (UK), MPE (Germany) and ECAP (Germany).

  16. Mercury cycling in terrestrial watersheds

    USGS Publications Warehouse

    Shanley, James B.; Bishop, Kevin

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  17. Terrestrial tidal variations in the selenopotential coefficients

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.; Ferrndiz, J. M.; Navarro, Juan F.

    2005-06-01

    The variations in the coefficients of the harmonics of second degree of the selenopotential caused by the terrestrial tides have been studied. In the paper we use analytical expressions for the tidal variations in the Stokes coefficients obtained for a model of the elastic celestial body with a concentric distribution of mass using the fundamental elastic parameter k2 of the Moon. Taking into account the resonant properties of the Moons motion, the variations in the selenopotential coefficients are presented in the form of Fourier series in the arguments of the theory of lunar orbital motion: lM, lS, F and D. The variations in the polar moment of inertia of the Moon due to the terrestrial tides lead to marked variations in the Moons axial rotation, which also have been determined and tabulated. From the results obtained, it follows that the tide periodic variations in the gravitational coefficients of the Moon are an order larger than the corresponding tide variations in the geopotential coefficients.

  18. Grazers: biocatalysts of terrestrial silica cycling

    PubMed Central

    Vandevenne, Floor Ina; Barão, Ana Lúcia; Schoelynck, Jonas; Smis, Adriaan; Ryken, Nick; Van Damme, Stefan; Meire, Patrick; Struyf, Eric

    2013-01-01

    Silica is well known for its role as inducible defence mechanism countering herbivore attack, mainly through precipitation of opaline, biogenic silica (BSi) bodies (phytoliths) in plant epidermal tissues. Even though grazing strongly interacts with other element cycles, its impact on terrestrial silica cycling has never been thoroughly considered. Here, BSi content of ingested grass, hay and faeces of large herbivores was quantified by performing multiple chemical extraction procedures for BSi, allowing the assessment of chemical reactivity. Dissolution experiments with grass and faeces were carried out to measure direct availability of BSi for dissolution. Average BSi and readily soluble silica numbers were higher in faeces as compared with grass or hay, and differences between herbivores could be related to distinct digestive strategies. Reactivity and dissolvability of BSi increases after digestion, mainly due to degradation of organic matrices, resulting in higher silica turnover rates and mobilization potential from terrestrial to aquatic ecosystems in non-grazed versus grazed pasture systems (2 versus 20 kg Si ha−1 y−1). Our results suggest a crucial yet currently unexplored role of herbivores in determining silica export from land to ocean, where its availability is linked to eutrophication events and carbon sequestration through C–Si diatom interactions. PMID:24107532

  19. Grazers: biocatalysts of terrestrial silica cycling.

    PubMed

    Vandevenne, Floor Ina; Baro, Ana Lcia; Schoelynck, Jonas; Smis, Adriaan; Ryken, Nick; Van Damme, Stefan; Meire, Patrick; Struyf, Eric

    2013-12-01

    Silica is well known for its role as inducible defence mechanism countering herbivore attack, mainly through precipitation of opaline, biogenic silica (BSi) bodies (phytoliths) in plant epidermal tissues. Even though grazing strongly interacts with other element cycles, its impact on terrestrial silica cycling has never been thoroughly considered. Here, BSi content of ingested grass, hay and faeces of large herbivores was quantified by performing multiple chemical extraction procedures for BSi, allowing the assessment of chemical reactivity. Dissolution experiments with grass and faeces were carried out to measure direct availability of BSi for dissolution. Average BSi and readily soluble silica numbers were higher in faeces as compared with grass or hay, and differences between herbivores could be related to distinct digestive strategies. Reactivity and dissolvability of BSi increases after digestion, mainly due to degradation of organic matrices, resulting in higher silica turnover rates and mobilization potential from terrestrial to aquatic ecosystems in non-grazed versus grazed pasture systems (2 versus 20 kg Si ha(-1) y(-1)). Our results suggest a crucial yet currently unexplored role of herbivores in determining silica export from land to ocean, where its availability is linked to eutrophication events and carbon sequestration through C-Si diatom interactions. PMID:24107532

  20. Higher in vitro resistance to oxidative stress in extra-pair offspring.

    PubMed

    Losdat, S; Helfenstein, F; Saladin, V; Richner, H

    2011-11-01

    Oxidative stress is considered to act as a universal physiological constraint in life-history evolution of animals. This should be of interest for extra-pair paternity behaviour, and we tested here the prediction that offspring arising from extra-pair matings of female great tits show higher resistance to oxidative stress than within-pair offspring. Resistance to oxidative stress, measured as the whole blood resistance to a controlled free-radical attack, was significantly higher for extra-pair offspring as predicted although these were not heavier or in better body condition than within-pair offspring. Since resistance to oxidative stress has been suggested to enhance survival and reproductive rates, extra-pair offspring with superior resistance to oxidative stress, be it through maternal effects or paternal inheritance, may achieve higher fitness and thus provide significant indirect fitness benefits to their mothers. In addition, because oxidative stress affects colour signals and sperm traits, females may also gain fitness benefits by producing sons that are more attractive (sexy-sons hypothesis) and have sperm of superior quality (sexy-sperm hypothesis). Heritability of resistance to oxidative stress as well as maternal effects may both act as proximate mechanisms for the observed result. Disentangling these two mechanisms would require an experimental approach. Future long-term studies should also aim at experimentally testing whether higher resistance to oxidative stress of EP nestlings indeed translates into fitness benefits to females. PMID:21899636

  1. Utilization of the terrestrial cyanobacteria

    NASA Astrophysics Data System (ADS)

    Katoh, Hiroshi; Tomita-Yokotani, Kaori; Furukawa, Jun; Kimura, Shunta; Yokoshima, Mika; Yamaguchi, Yuji; Takenaka, Hiroyuki

    The terrestrial, N _{2}-fixing cyanobacterium, Nostoc commune has expected to utilize for agriculture, food and terraforming cause of its extracellular polysaccharide, desiccation tolerance and nitrogen fixation. Previously, the first author indicated that desiccation related genes were analyzed and the suggested that the genes were related to nitrogen fixation and metabolisms. In this report, we suggest possibility of agriculture, using the cyanobacterium. Further, we also found radioactive compounds accumulated N. commune (cyanobacterium) in Fukushima, Japan after nuclear accident. Thus, it is investigated to decontaminate radioactive compounds from the surface soil by the cyanobacterium and showed to accumulate radioactive compounds using the cyanobacterium. We will discuss utilization of terrestrial cyanobacteria under closed environment. Keyword: Desiccation, terrestrial cyanobacteria, bioremediation, agriculture

  2. Terrestrial ecosystems and climatic change

    SciTech Connect

    Emanuel, W.R. ); Schimel, D.S. . Natural Resources Ecology Lab.)

    1990-01-01

    The structure and function of terrestrial ecosystems depend on climate, and in turn, ecosystems influence atmospheric composition and climate. A comprehensive, global model of terrestrial ecosystem dynamics is needed. A hierarchical approach appears advisable given currently available concepts, data, and formalisms. The organization of models can be based on the temporal scales involved. A rapidly responding model describes the processes associated with photosynthesis, including carbon, moisture, and heat exchange with the atmosphere. An intermediate model handles subannual variations that are closely associated with allocation and seasonal changes in productivity and decomposition. A slow response model describes plant growth and succession with associated element cycling over decades and centuries. These three levels of terrestrial models are linked through common specifications of environmental conditions and constrain each other. 58 refs.

  3. Planetary beat and solar-terrestrial responses

    NASA Astrophysics Data System (ADS)

    Mörner, N.-A.

    2013-11-01

    Solar activity changes with time in a cyclic pattern. The origin of those changes may be caused by planetary motion around the Sun, affecting the position of the Sun's motion with respect to the centre of mass and subjecting the Sun to changes in angular momentum and gravitational tidal forces. With modern achievements, this multi-body problem can now be addressed in a constructive way. Indeed, there are multiple criteria suggesting that the solar variability is driven by a planetary beat also affecting a number of terrestrial variables: 14C and 10Be production, Earth's rotation, ocean circulation, paleoclimate, geomagnetism, etc. The centennial changes between grand solar maxima and minima imply that we will soon be in a new solar minimum and, in analogy with past events, probably also in Little Ice Age climatic conditions.

  4. Lepton flavor violation in extra dimension models

    SciTech Connect

    Chang, W.-F.; Ng, John N.

    2005-03-01

    Models involving large extra spatial dimension(s) have interesting predictions on lepton flavor violating processes. We consider some five-dimensional (5D) models which are related to neutrino mass generation or address the fermion masses hierarchy problem. We study the signatures in low energy experiments that can discriminate the different models. The focus is on muon-electron conversion in nuclei {mu}{yields}e{gamma} and {mu}{yields}3e processes and their {tau} counterparts. Their links with the active neutrino mass matrix are investigated. We show that in the models we discussed the branching ratio of {mu}{yields}e{gamma} like rare process is much smaller than the ones of {mu}{yields}3e like processes. This is in sharp contrast to most of the traditional wisdom based on four-dimensional (4D) gauge models. Moreover, some rare tau decays are more promising than the rare muon decays.

  5. [Extra-digestive manifestations of food allergy].

    PubMed

    Vandenplas, Y; Loeb, H

    1994-01-01

    Intestinal manifestations are the predominant symptoms of food allergy. Nevertheless, it is generally accepted that dietary proteins can also induce intestinal manifestations such as systemic reactions or symptoms related to the skin, the respiratory tract, the central nervous system, the urinary tract, the vascular system, the joints. The cause-effect relationships between the contact with the dietary protein (e.g. it is unclear if direct skin contact is more relevant in patients with cutaneous manifestations than ingestion) and the symptoms if often difficult to prove. As a consequence, the number of "extra-intestinal" manifestations that are suggested to be related to food proteins is probably greater than the number of manifestations that are generally accepted as such. PMID:8087223

  6. Terrestrial planet composition: simulation and observation

    NASA Astrophysics Data System (ADS)

    Carter-Bond, J.; Bolmont, E.; Raymond, S.

    2014-03-01

    As direct detection and examination of terrestrial exoplanets is not yet possible, we must persue alternative methods to constarin the types of planets likely to be found within extrasolar planetary systems and thus guide future missions. Such studies cannot be undertaken by transit surveys. Instead, secondary sources must be utilized. In addition to simultions of terrestrial planet formation, based on spectroscopic observations of known stars, observations of polluted white dwarfs (e.g. Jura, M., & Xu, S. (2012); Gaensicke et al., (2013)) and simulations of the pollution of migrating gas giants may be utilized to determine the composition of solid bodies withn extrasolar planetary systems. Observations of polluted white dwarfs (e.g. Jura, M., & Xu, S. (2012); Gaensicke et al., (2013)) will be compared to simulations of the bulk composition of terrestrial planets (Carter-Bond et al. (2012)). Combining dynamical simulations of Carter-Bond et al. (2012) and Raymond et al. (2006) with spectrally-derived abundances for 15 planet-forming elements (H, C, N, O, Na, Mg, Al, Si, P, S, Ca, Ti, Cr, Fe and Ni), bulk compositions for simulated terrestrial planets have been obtained. This is the first time that compositional simulations can be compared with observations (albeit of a proxy for solid composition) and will be crucial for placing constraints on both the true diversity of planetary compositions expected to exist in extrasolar planetary systems and the simulations currently utilized. Simulations of the change in composition resulting from pollution of a gas giant as it migrates through a planetary system will also be presented. These simulations represent an as-yet untested approach to determining the solid composition within a planetary system. By simulating the amount and composition of material accreted by the gas giant (following Carter-Bond et al. (2012)), we will be able to determine what effect, if any, the accretion of solid material during migration has on giant planet composition. This study represents the first attempt at untangling what fraction of the observed composition is primordial and what fraction has been accreted and may, ultimately, provide further limitation on the composition of solids within extrasolar planetary systems. Such a study is especially timely, given the rising number of spectral observations of transiting giant planets and their unusual implications (e.g. Madhusudhan et al. (2011)).

  7. Priapism caused by 'Tribulus terrestris'.

    PubMed

    Campanelli, M; De Thomasis, R; Tenaglia, R L

    2016-01-01

    A 36-year-old Caucasian man was diagnosed with a 72-h-lasting priapism that occurred after the assumption of a Herbal supplement based on Tribulus terrestris, which is becoming increasingly popular for the treatment of sexual dysfunction. The patient underwent a cavernoglandular shunt (Ebbehoj shunt) in order to obtain complete detumescence, from which derived negative post-episode outcomes on sexual function. All patients consuming non-FDA-approved alternative supplements such as Tribulus terrestris should be warned about the possible serious side effects. PMID:26631925

  8. Groundwater and Terrestrial Water Storage

    NASA Technical Reports Server (NTRS)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2012-01-01

    Groundwater is a vital resource and also a dynamic component of the water cycle. Unconfined aquifer storage is less responsive to short term weather conditions than the near surface terrestrial water storage (TWS) components (soil moisture, surface water, and snow). However, save for the permanently frozen regions, it typically exhibits a larger range of variability over multi-annual periods than the other components. Groundwater is poorly monitored at the global scale, but terrestrial water storage (TWS) change data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are a reasonable proxy for unconfined groundwater at climatic scales.

  9. Chemical impurity produces extra compound eyes and heads in crickets

    SciTech Connect

    Walton, B.T.

    1981-04-03

    A chemical impurity isolated from commercially purchased acridine causes cricket embryos to develop extra compound eyes, branched antennae, extra antennae, and extra heads. Purified acridine does not produce similar duplications of cricket heads or head structures nor do the substituted acridines proflavine, acriflavine, or acridine orange. A dose-response relation exists such that the number and severity of abnormalities increase with increasing concentration of the teratogen.

  10. Cosmologically safe QCD axion as a present from extra dimension

    NASA Astrophysics Data System (ADS)

    Kawasaki, Masahiro; Yamada, Masaki; Yanagida, Tsutomu T.

    2015-11-01

    We propose a QCD axion model where the origin of PQ symmetry and suppression of axion isocurvature perturbations are explained by introducing an extra dimension. Each extra quark-antiquark pair lives on branes separately to suppress PQ breaking operators. The size of the extra dimension changes after inflation due to an interaction between inflaton and a bulk scalar field, which implies that the PQ symmetry can be drastically broken during inflation to suppress undesirable axion isocurvature fluctuations.

  11. Testing Extra Dimensions with Boundaries Using Newton's Law Modifications

    NASA Astrophysics Data System (ADS)

    Oikonomou, V. K.; Kleidis, K.

    Extra dimensions with boundaries are often used in the literature to provide phenomenological models that mimic the standard model. In this context, we explore possible modifications to Newton's law due to the existence of an extra-dimensional space, at the boundary of which the gravitational field obeys Dirichlet, Neumann or mixed boundary conditions. We focus on two types of extra space, namely, the disk and the interval. As we prove, in order to have a consistent Newton's law modification (i.e. of the Yukawa-type), some of the extra-dimensional spaces that have been used in the literature, must be ruled out.

  12. Behavioral correlates of extra-pair copulation in Indri indri.

    PubMed

    Bonadonna, Giovanna; Torti, Valeria; Randrianarison, Rose Marie; Martinet, Nicole; Gamba, Marco; Giacoma, Cristina

    2014-01-01

    Active pursuit of extra-pair mating has been reported for Indri indri, the socially monogamous largest living lemur. This study, conducted in a mountain rainforest in eastern Madagascar, presents the first evidence for extra-pair mating of indri and discusses the alternative mating strategy and alteration of the social, territorial, spatial, and vocal behavior of the adult female of a group of wild indris. Further studies may investigate whether extra-pair copulation is an attempt to breed with a partner of superior quality and thus lead to extra-pair paternity. If so, it could potentially play a role in maintaining genetic variability within a population. PMID:23921557

  13. Impact ejecta emplacement on terrestrial planets

    NASA Astrophysics Data System (ADS)

    Osinski, Gordon R.; Tornabene, Livio L.; Grieve, Richard A. F.

    2011-10-01

    Impact cratering is one of the most fundamental processes responsible for shaping the surfaces of solid planetary bodies. One of the principal characteristics of impact events is the formation and emplacement of ejecta deposits, an understanding of which is critical for planetary exploration. Current models of ejecta emplacement, however, do not account for several important observations of ejecta deposits on the terrestrial planets, in particular, the presence of more than one layer of ejecta. Furthermore, there is also no universal model for the origin and emplacement of ejecta on different planetary bodies. We present a unifying working hypothesis for the origin and emplacement of ejecta on the terrestrial planets, in which the ejecta are emplaced in a multi-stage process. The generation of the continuous ejecta blanket occurs during the excavation stage of cratering, via the conventional ballistic sedimentation and radial flow model. This is followed by the emplacement of more melt-rich, ground-hugging flows - the "surface melt flow" phase - during the terminal stages of crater excavation and the modification stage of crater formation. Minor fallback occurs during the final stages of crater formation. Several factors will affect the final morphology and character of ejecta deposits. The volatile content and cohesiveness of the uppermost target rocks will significantly affect the runout distance of the ballistically emplaced continuous ejecta blanket, with impact angle also influencing the overall geometry of the deposits (e.g., the production of the characteristic butterfly pattern seen in very oblique impacts). Ejecta deposited during the surface melt flow stage is influenced by several factors, most importantly planetary gravity, surface temperature, and the physical properties of the target rocks. Topography and angle of impact play important roles in determining the final distribution of surface melt flow ejecta deposits with respect to the source crater. This working hypothesis of ballistic sedimentation and surface melt flow provides a framework in which observations of ejecta at impact craters can be compared and placed in the context of the respective terrestrial planets.

  14. Scientist Using Terrestrial Lidar Equipment

    USGS Multimedia Gallery

    Chris Soulard using the Terrestrial Lidar to scan study area in the Grand Canyon-Parashant National Monument, AZ.  Note the bag of ice on the equipment.  High temperates can cause equipment to overheat, requiring scientists to be creative in protecting equipment....

  15. Wolbachia in Neotropical terrestrial isopods.

    PubMed

    Zimmermann, Bianca L; Bouchon, Didier; Almero, Maurcio P; Araujo, Paula B

    2015-04-01

    Despite Wolbachia being widespread among terrestrial isopods, studies on this symbiotic relationship are still incipient in the Neotropical region. The aims of the present study were to investigate the presence and prevalence of Wolbachia in natural populations of terrestrial isopod species in South America, and to analyze the diversity and phylogenetic relationships of Wolbachia strains. A total of 1172 individuals representing 11 families and 35 species were analyzed. We observed distinct evolutionary scenarios according to the geographical origins of the species: strains harbored by most of the introduced species belong to the Oniclade in supergroup B and are identical to those found in their original ecozone (i.e. Palearctic). On the other hand, the strains found in native Neotropical terrestrial isopods showed low prevalence, high diversity and none of them belonged to the Oniclade, although most belonged to supergroup B. The dynamics of infection in Neotropical species seems to be the result of several events of loss and acquisition of the bacteria, which refutes the hypothesis of an ancestral acquisition of Wolbachia in Oniscidea. The presence of strains from supergroups A and F was also detected for the first time in terrestrial isopods, revealing a Wolbachia diversity previously unknown for this group of host. PMID:25764472

  16. Application of bleach method in diagnosis of extra-pulmonary tuberculosis.

    PubMed

    Khubnani, Harish; Munjal, Kavita

    2005-10-01

    Extra pulmonary tuberculosis (TB) comprises 15% of the total tuberculosis cases. Bleach concentration method for demonstration of Acid fast bacilli (AFB) has been recently described for sputum. The aim of this study is to apply this method for demonstration of AFB in material obtained from extra-pulmonary sites and to correlate with cytology and conventional Ziehl Neelsen (Z N) staining. A total of 55 samples were studied from clinically suspected cases of extrapulmonary TB which included, FNA lymph nodes (17), abscesses drained from various body parts (18), body fluids (18) and skin scrapping (2). All the samples were processed for routine cytology, conventional ZN staining and bleach method followed by ZN staining. Out of 55 samples, 24(43.40%) were indicative of tuberculosis on cytology, 12(21.8%) were positive for AFB on conventional ZN staining, while the positivity increased to 39(70.90%) by Bleach method. Bleach solution is inexpensive and readily available in hospitals and its application has been proved in pulmonary tuberculosis. However to the best of our knowledge this is a pioneer study applied to the extra-pulmonary samples and the results of the present study shows improved detection of AFB. PMID:16366123

  17. Amino acid compositional shifts during streptophyte transitions to terrestrial habitats.

    PubMed

    Jobson, Richard W; Qiu, Yin-Long

    2011-02-01

    Across the streptophyte lineage, which includes charophycean algae and embryophytic plants, there have been at least four independent transitions to the terrestrial habitat. One of these involved the evolution of embryophytes (bryophytes and tracheophytes) from a charophycean ancestor, while others involved the earliest branching lineages, containing the monotypic genera Mesostigma and Chlorokybus, and within the Klebsormidiales and Zygnematales lineages. To overcome heat, water stress, and increased exposure to ultraviolet radiation, which must have accompanied these transitions, adaptive mechanisms would have been required. During periods of dehydration and/or desiccation, proteomes struggle to maintain adequate cytoplasmic solute concentrations. The increased usage of charged amino acids (DEHKR) may be one way of maintaining protein hydration, while increased use of aromatic residues (FHWY) protects proteins and nucleic acids by absorbing damaging UV, with both groups of residues thought to be important for the stabilization of protein structures. To test these hypotheses we examined amino acid sequences of orthologous proteins representing both mitochondrion- and plastid-encoded proteomes across streptophytic lineages. We compared relative differences within categories of amino acid residues and found consistent patterns of amino acid compositional fluxuation in extra-membranous regions that correspond with episodes of terrestrialization: positive change in usage frequency for residues with charged side-chains, and aromatic residues of the light-capturing chloroplast proteomes. We also found a general decrease in the usage frequency of hydrophobic, aliphatic, and small residues. These results suggest that amino acid compositional shifts in extra-membrane regions of plastid and mitochondrial proteins may represent biochemical adaptations that allowed green plants to colonize the land. PMID:21153633

  18. Economics and ethics of paediatric respiratory extra corporeal life support.

    PubMed

    Callaghan, M; Doyle, Y; O'Hare, B; Healy, M; Nlke, L

    2013-09-01

    Extra corporeal membrane oxygenation (ECMO) is a form of life support, which facilitates gas exchange outside the body via an oxygenator and a centrifugal pumping system. A paediatric cardiac ECMO programme was established in 2005 at Our Lady's Children's Hospital, Crumlin (OLCHC) and to date 75 patients have received ECMO, the majority being post operative cardiac patients. The outcome data compares favourably with international figures. ECMO has been most successful in the treatment of newborn infants with life threatening respiratory failure from conditions such as meconium aspiration, respiratory distress syndrome and respiratory infections. There is no formal paediatric respiratory ECMO programme at OLCHC, or anywhere else in Ireland. Currently, neonates requiring respiratory ECMO are transferred to centres in Sweden or the UK at an average cost of 133,000 Euros/infant, funded by the Health Service Executive E112 treatment abroad scheme. There is considerable morbidity associated with the transfer of critically ill infants, as well as significant psycho-social impact on families. OLCHC is not funded to provide respiratory ECMO, although the equipment and expertise required are similar to cardiac ECMO and are currently in place. The average cost of an ECMO run at OLCHC is 65,000 Euros. There is now a strong argument for a fully funded single national cardiac and respiratory paediatric ECMO centre, similar to that for adult patients. PMID:24282901

  19. Gamma ray lines from a universal extra dimension

    SciTech Connect

    Bertone, G.; Jackson, C. B.; Shaughnessy, G.; Tait, T. M.P.; Vallinotto, A.

    2012-03-01

    Indirect Dark Matter searches are based on the observation of secondary particles produced by the annihilation or decay of Dark Matter. Among them, gamma-rays are perhaps the most promising messengers, as they do not suffer deflection or absorption on Galactic scales, so their observation would directly reveal the position and the energy spectrum of the emitting source. Here, we study the detailed gamma-ray energy spectrum of Kaluza--Klein Dark Matter in a theory with 5 Universal Extra Dimensions. We focus in particular on the two body annihilation of Dark Matter particles into a photon and another particle, which produces monochromatic photons, resulting in a line in the energy spectrum of gamma rays. Previous calculations in the context of the five dimensional UED model have computed the line signal from annihilations into \\gamma \\gamma, but we extend these results to include \\gamma Z and \\gamma H final states. We find that these spectral lines are subdominant compared to the predicted \\gamma \\gamma signal, but they would be important as follow-up signals in the event of the observation of the \\gamma \\gamma line, in order to distinguish the 5d UED model from other theoretical scenarios.

  20. Providing robotic assistance during extra-vehicular activity

    NASA Astrophysics Data System (ADS)

    Burridge, Robert; Graham, Jeffrey

    2002-02-01

    Manned missions to other planetary bodies will rely heavily on robotics and automation to enhance the operational safety and capabilities of the crew. In particular, the movement and sensing capabilities of humans in spacesuits are severely constrained. Thus, an important class of robot will be those that accompany humans during extra-vehicular activity (EVA) and provide assistance -- tool transport, video documentation, sample collection, etc. In 1999, NASA engaged in a set of field tests in California called ASRO (AStronaut-ROver), in which a space-suited test subject collaborated with the tele-operated Marsokhod mobile robot, controlled by scientist at a remote location. From the lessons learned in the ASRO tests, the EVA Robotic Assistant project was started at NASA's Johnson Space Center to provide a testbed for continued research in astronaut-robot interaction and cooperation. In September 2000, NASA conducted two weeks of field tests in Arizona at three planetary surface analog sites. Three scenarios were tested requiring cooperation between a space-suited astronaut and the autonomous EVA Robotic Assistant: Power Cable Deployment, Solar Panel Deployment, and Geologist's Assistant. In this paper, we describe the ERA project in detail, and report on results from the Arizona field tests.

  1. Mars: destruction of the tropical belt and building up extra tropics is a physical requirement of angular momentum equilibration between zones with different distances to the rotation axis

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2012-09-01

    Often observed a sensible difference in appearance and structure between tropical and extra-t ropical zones of various heavenly bodies including rocky and gas planets, satellites and Sun (Fig. 6) compels to look for a common reason of such phenomenon [1-3]. All bodies rotate and their spherical shape makes zones at different lat itudes to have differing angular momenta as a distance to the rotation axis diminishes gradually from the equator to the poles (Fig. 1) (this is felt particularly when one launches rockets into space -preferable cheaper launches are from the equatorial regions - Kourou in the French Guyana is better than Baikonur in Kazakhstan). One of remarkable changes occurs at tropics. As a total rotating planetary body tends to have angular momenta of its tectonic blocks equilibrated it starts mechanisms leveling this basic physical property. At tropical zones (bulged also due to the rotation ellipsoid) the outer shell - crust as a consequence tends to be destroyed, sunk, subsided and shrunk; a density of crust material changes; the atmosphere reacts changing chemistry and structure; in terrestrial anthroposphere man looses its mass and stature (well known pygmioidness process). Ext ratropical belts, on the contrary, tend to add material and increase radius. Thus, a body tends to be like a cucumber but mighty gravity always makes it globular. According to the Le Chatelier rule mechanisms with opposing tendencies also begin to act. However, traces of this cosmic "struggle" very often are seen on surfaces of heavenly bodies as structurally distinguished tropical and extra-t ropical zones (Fig. 1, 6) [1-3]. At Mars the widespread "enigmatic" chaotic and fretted terrains at the highland-lowland boundary could be considered as traces of the crust destruction along the wide tropical belt (Fig. 2-4). A system of hillocks and their relics, mesas, ridges, cliffs and separating them depressions or plains (deep up to 1-2 km) is controlled by a crosscutting tectonics or makes a complicated mix (Fig. 3, 4). Prevailing subsidence here is characteristic. The depressions were used and additionally sculptured by moving ices and flowing waters in the past of martian geologic history. On the contrary, wide extra -tropical belts of pedestal craters with broad effusions of fluid-rich material (Fig. 5) obviously help to mend defective momentum. A comparison with Earth is to the point. There also the wide planetary long tropical zone is marked by destruction of the crust. It is demonstrated by development of numerous islands of the Malay Archipelago (the Sunda Isls., Maluku Isls., Philippines) between the Southeastern Asia and Australia. In Africa and South America huge depressions of the Congo and Amazon Rivers develop where the Archean crust is subsided to depths of more than 2 km. In the Pacific along the equator numerous islands of Micronesia occur (massive corals mark subsiding basaltic summits). Subsidence of the basaltic oceanic crust is followed by an intensive folding and faulting of basalt and sedimentary layers as a larger mass must be held by a smaller space (a planetary radius is diminishing). The central Atlantic is very demonstrative in this sense suffering huge transform fault zones being replaced by more quite tectonics to the north and south where basaltic effusions (plateau-basalts) form large provinces. This addition of dense basalts to the upper crust level helps to increase angular momentum of the extra-t ropical blocks. Recent results from the DAWN mission show that the mini-planet Vesta also has the same structurally deformed equatorial belt. But at Vesta the equatorial belt is subsided and faulted (broken by tight series of parallel grabens) having been squeezed into smaller space because of diminishing planetary radius (Fig. 6) Thus, Mars, as other planetary bodies, suffers a fundamental re-building of its wide topical zone (supertectonics) as a necessary natural response to the angular momentum adjustment (equilibrat ion) of its different latitude belts (tropics and extra-tropics). This re-building started at the very earlier stages of its geologic history and, certainly, influenced other planetary wide processes. Fig. 1.Differing angular momenta (M) of the equatorial and ext ra-equatorial zones of a rotating globular body.

  2. Malignant extra-renal rhabdoid tumor with unusual presentation: A report of two cases.

    PubMed

    Gupta, Rakesh Kumar; Batra, Vineeta V; Das, Mridul Chandra; Sharma, Ajay; Narang, Poonam

    2015-01-01

    Malignant extra-renal rhabdoid tumor (MERT) is a rare highly aggressive tumor that occurs in young children with the very poor clinical outcome. The tumor is characterized by a diffuse proliferation of "rhabdoid cells," which are round or polygonal with eccentric nuclei, prominent nucleoli, and glassy eosinophilic cytoplasm containing hyaline-like inclusion bodies. However, rhabdoid cells are also seen in certain other soft tissue sarcomas such as proximal-type epithelioid sarcoma, rarely synovial sarcoma, and extra-skeletal myxoid chondrosarcoma. Because of its poor prognosis and histomorphological similarities with other soft tissue tumors, an accurate diagnosis is required using a wide immunohistochemical panel. Very few cases of MERT have been reported in the literature and to our knowledge none in the supra-glottis area. Due to the rarity and poor outcome of this tumor, we are reporting two cases of MERT. PMID:26881557

  3. Formation of the terrestrial planets from planetesimals

    NASA Technical Reports Server (NTRS)

    Wetherill, George W.

    1991-01-01

    Formation of the terrestrial planets from planetesimals is discussed. The following subject areas are covered: (1) formation of the original planetesimals; (2) growth of planetesimals into planetary embryos; and (3) growth of runaway planetary embryos into terrestrial planets.

  4. CARBON DIOXIDE SEQUESTRATION IN TERRESTRIAL ECOSYSTEMS

    EPA Science Inventory

    The terrestrial biosphere plays a prominent role in the global carbon (C) cycle. errestrial ecosystems are currently accumulating C and it appears feasible to manage existing terrestrial (forest, agronomic, desert) ecosystems to maintain or increase C storage. orest ecosystems ca...

  5. Body Image

    MedlinePLUS

    ... About Us Contact Us Text size | Print | Body Image Developing a positive body image and a healthy mental attitude is crucial to ... on for tips to have a healthy body image. Topics About body image When you look in ...

  6. Spatial patterns of extra-pair paternity: beyond paternity gains and losses.

    PubMed

    Schlicht, Lotte; Valcu, Mihai; Kempenaers, Bart

    2015-03-01

    Most studies on extra-pair paternity (EPP) focus either on a specific male's extra-pair gains or his extra-pair losses. For an individual bird however, mate choice or mate availability may underlie strong spatial restrictions. Disregarding this spatial aspect may underestimate or mask effects of parameters influencing observed EPP patterns. Here, we propose a spatially explicit model for investigating the probability of having extra-pair offspring (EPO) within local networks of breeding pairs. The data set includes all realized and unrealized potential extra-pair matings. This method is biologically meaningful because it allows (a) considering both members of an extra-pair mating and their social mates, and (b) direct modelling of the spatial context in which extra-pair behaviour occurs. The method has the advantage that it can provide inference about the relative contribution of spatial and non-spatial parameters, and about the relative importance of male and female neighbourhoods. We apply this method to parentage data from 1025 broods collected over 12 breeding seasons in two independent study populations of blue tits (Cyanistes caeruleus). We investigate a set of predictions based on the EPP literature, namely that EPP depends on male age and body size, breeding density and breeding synchrony. In all analyses, we control for breeding distance, a parameter that is expected to influence EPP even under random mating. The results show that older and larger males were more likely to sire EPO, but both effects decreased with increasing breeding distance. Local breeding density but not synchrony predicted whether a particular male-female combination had EPO, at least in one of the study areas. Apart from breeding distance, male age had the strongest effect on EPP, followed by a measure of breeding density. The method thus allows a comprehensive assessment of the relative importance of different types of spatial and non-spatial parameters to explain variation in the occurrence of EPP, while controlling for the fact that individuals that breed further apart are less likely to have EPO. The proposed approach is not limited to investigate EPP, but can be applied to other behavioural interactions between two individuals, such as dominance, competition and (social) mating. PMID:25266005

  7. A Mechanism for Charge Creation from Extra Dimensions

    NASA Astrophysics Data System (ADS)

    Duc, Dao Vong; Giao, Nguyen Mong

    2016-02-01

    We propose a mechanism for explaining the originality of charge creation based on some specific assumptions related to space - time extra dimensions. It holds that the existence and the compactification of extra dimensions are the origin for creating the interaction charge in ordinary 4 - dimensional space - time.

  8. 23 CFR 635.120 - Changes and extra work.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Changes and extra work. 635.120 Section 635.120 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CONSTRUCTION AND MAINTENANCE Contract Procedures 635.120 Changes and extra work. (a) Following...

  9. 23 CFR 635.120 - Changes and extra work.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 23 Highways 1 2014-04-01 2014-04-01 false Changes and extra work. 635.120 Section 635.120 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CONSTRUCTION AND MAINTENANCE Contract Procedures 635.120 Changes and extra work. (a) Following...

  10. 7 CFR 51.300 - U.S. Extra Fancy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Grades § 51.300 U.S. Extra Fancy. “U.S. Extra Fancy” consists of apples of one variety (except when more than one variety is printed on... apples are also free from injury caused by bruises, brown surface discoloration, smooth...

  11. 7 CFR 51.300 - U.S. Extra Fancy.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Apples Grades § 51.300 U.S. Extra Fancy. “U.S. Extra Fancy” consists of apples of..., scab, freezing injury, visible water core, and broken skins. The apples are also free from injury... rubs, hail, drought spots, scars, disease, insects, or other means. The apples are free from...

  12. 7 CFR 51.300 - U.S. Extra Fancy.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Apples Grades § 51.300 U.S. Extra Fancy. “U.S. Extra Fancy” consists of apples of..., scab, freezing injury, visible water core, and broken skins. The apples are also free from injury... rubs, hail, drought spots, scars, disease, insects, or other means. The apples are free from...

  13. 7 CFR 51.300 - U.S. Extra Fancy.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Grades § 51.300 U.S. Extra Fancy. “U.S. Extra Fancy” consists of apples of one variety (except when more than one variety is printed on... apples are also free from injury caused by bruises, brown surface discoloration, smooth...

  14. Quantifying inbreeding avoidance through extra-pair reproduction

    PubMed Central

    Reid, Jane M; Arcese, Peter; Keller, Lukas F; Germain, Ryan R; Duthie, A Bradley; Losdat, Sylvain; Wolak, Matthew E; Nietlisbach, Pirmin

    2015-01-01

    Extra-pair reproduction is widely hypothesized to allow females to avoid inbreeding with related socially paired males. Consequently, numerous field studies have tested the key predictions that extra-pair offspring are less inbred than females alternative within-pair offspring, and that the probability of extra-pair reproduction increases with a female's relatedness to her socially paired male. However, such studies rarely measure inbreeding or relatedness sufficiently precisely to detect subtle effects, or consider biases stemming from failure to observe inbred offspring that die during early development. Analyses of multigenerational song sparrow (Melospiza melodia) pedigree data showed that most females had opportunity to increase or decrease the coefficient of inbreeding of their offspring through extra-pair reproduction with neighboring males. In practice, observed extra-pair offspring had lower inbreeding coefficients than females within-pair offspring on average, while the probability of extra-pair reproduction increased substantially with the coefficient of kinship between a female and her socially paired male. However, simulations showed that such effects could simply reflect bias stemming from inbreeding depression in early offspring survival. The null hypothesis that extra-pair reproduction is random with respect to kinship therefore cannot be definitively rejected in song sparrows, and existing general evidence that females avoid inbreeding through extra-pair reproduction requires reevaluation given such biases. PMID:25346331

  15. Long-term solar-terrestrial observations

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The results of an 18-month study of the requirements for long-term monitoring and archiving of solar-terrestrial data is presented. The value of long-term solar-terrestrial observations is discussed together with parameters, associated measurements, and observational problem areas in each of the solar-terrestrial links (the sun, the interplanetary medium, the magnetosphere, and the thermosphere-ionosphere). Some recommendations are offered for coordinated planning for long-term solar-terrestrial observations.

  16. STS-109 Extra Vehicular Activity (EVA)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Inside the Space Shuttle Columbia's cabin, astronaut Nancy J. Currie, mission specialist, controlled the Remote Manipulator System (RMS) on the crew cabin's aft flight deck to assist fellow astronauts during the STS-109 mission Extra Vehicular Activities (EVA). The RMS was used to capture the telescope and secure it into Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

  17. Top Yukawa deviation in extra dimension

    NASA Astrophysics Data System (ADS)

    Haba, Naoyuki; Oda, Kin-ya; Takahashi, Ryo

    2009-11-01

    We suggest a simple one-Higgs-doublet model living in the bulk of five-dimensional spacetime compactified on S/Z, in which the top Yukawa coupling can be smaller than the naive standard-model expectation, i.e. the top quark mass divided by the Higgs vacuum expectation value. If we find only single Higgs particle at the LHC and also observe the top Yukawa deviation, our scenario becomes a realistic candidate beyond the standard model. The Yukawa deviation comes from the fact that the wave function profile of the free physical Higgs field can become different from that of the vacuum expectation value, due to the presence of the brane-localized Higgs potentials. In the Brane-Localized Fermion scenario, we find sizable top Yukawa deviation, which could be checked at the LHC experiment, with a dominant Higgs production channel being the WW fusion. We also study the Bulk Fermion scenario with brane-localized Higgs potential, which resembles the Universal Extra Dimension model with a stable dark matter candidate. We show that both scenarios are consistent with the current electroweak precision measurements.

  18. Extra-glycaemic properties of empagliflozin.

    PubMed

    Solini, Anna

    2016-03-01

    Type 2 diabetes is a complex and multifaceted disease requiring an individualized approach. A special attention, in treating the patients, should be devoted to the presence of comorbidities like overweight or obesity and arterial hypertension. Among the available anti-hyperglycaemic agents, several are associated with side effects like hypoglycaemia and weight gain. An increasing interest is reported in sodium-glucose co-transporter-2 inhibitors, a relatively novel class of glucose-lowering drugs that act independently of insulin, provide benefits beyond glucose-lowering actions and show a better tolerability compared with traditional medications for type 2 diabetes. This review tries to offer a balanced view on the main extra-glycaemic effects of empagliflozin, also mentioning clinical data obtained with other sodium-glucose co-transporter-2 inhibitors; the role of the proximal tubule in the pathophysiology of diabetic nephropathy and the potential nehroprotection exerted by this compound are also briefly discussed. Copyright 2015 John Wiley & Sons, Ltd. PMID:25994513

  19. LHC Signals from Warped Extra Dimensions

    SciTech Connect

    Agashe, K.; Belyaev, A.; Krupovnickas, T.; Perez, G.; Virzi, J.

    2006-12-06

    We study production of Kaluza-Klein gluons (KKG) at the Large Hadron Collider (LHC) in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. We show that the detection of KK gluon is challenging since its production is suppressed by small couplings to the proton's constituents. Moreover, the KK gluon decaysmostly to top pairs due to an enhanced coupling and hence is broad. Nevertheless, we demonstrate that for MKKG<~;; 4 TeV, 100 fb-1 of data at the LHC can provide discovery of the KK gluon. We utilize a sizeable left-right polarization asymmetry from the KK gluon resonance to maximize the signal significance, and we explore the novel feature of extremely highly energetic"top-jets." We briefly discuss how the detection of electroweak gauge KK states (Z/W) faces a similar challenge since their leptonic decays ("golden" modes) are suppressed. Our analysis suggests that other frameworks, for example little Higgs, which rely on UV completion via strong dynamics might face similar challenges, namely (1) Suppressed production rates for the new particles (such as Z'), due to their"lightfermion-phobic" nature, and (2) Difficulties in detection since the new particles are broad and decay predominantly to third generation quarks and longitudinal gauge bosons.

  20. Photometric Searches for Extra-Solar Planets

    NASA Astrophysics Data System (ADS)

    Bally, J.

    1998-05-01

    Three indirect search strategies for extra-Solar planets share the common element of requiring precision photometry of randomly placed targets spread over a wide field of view. The three methods are: [1] Infrared (2 to 20 mu m) gravitational ``nano''-lensing of background Galactic Center stars (the richest star field in the Galaxy) by planets in orbit around foreground Galactic disk stars at wavelengths where most of the Galactic disk and bulge can be seen. [2] Transits of giant planets in 51 Peg type orbits that produce of order 1% amplitude occultations lasting a few hours and separated in time by days to months (0.5 to 2mu m). [3] The detection of the infrared (2 to 20 mu m) flare or ``lava lake'' produced by proto-planet collisions in evolving debris disks around young stars in regions of recent star formation. Though ultimately these experiments are best performed in space, observations from Antarctica, and from long duration balloons provide a viable stepping stone to develop the required technology and to obtain preliminary results. I will review the site and instrumentation requirements for these photometric search methods and discuss ``flexible feed array'' multiplex strategies which permit the efficient targeting a sparse population of randomly distributed objects over a large field of view.

  1. The Effect of Giant Planets on Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Barclay, Thomas; Quintana, Elisa

    2015-12-01

    The giant planets in the Solar System likely played a defining role in shaping the properties of the Earth and other terrestrial planets during their formation. Observations from the Kepler spacecraft indicate that terrestrial planets are highly abundant. However, there are hints that giant planets a few AU from their stars are relatively uncommon based on long baseline radial velocity searches. It therefore seems reasonable to assume that many terrestrial planets lack a Jupiter-like companion. We use a recently developed, state-of-the-art N-body model that allows for collisional fragmentation to perform hundreds of numerical simulations of the final stages of terrestrial planet formation around a Sun-like star -- with and without giant outer planets. We quantify the effects that outer giant planet companions have on collisions and the planet accretion process. We focus on Earth-analogs that form in each system and explore how giant planets influence the relative frequency of giant impacts occurring at late times.

  2. How Giant Planets Shape the Characteristics of Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Barclay, Thomas; Quintana, Elisa V.

    2016-01-01

    The giant planets in the Solar System likely played a defining role in shaping the properties of the Earth and other terrestrial planets during their formation. Observations from the Kepler spacecraft indicate that terrestrial planets are highly abundant. However, there are hints that giant planets a few AU from their stars are not ubiquitous. It therefore seems reasonable to assume that many terrestrial planets lack a Jupiter-like companion. We use a recently developed, state-of-the-art N-body model that allows for collisional fragmentation to perform hundreds of numerical simulations of the final stages of terrestrial planet formation around a Sun-like star -- with and without giant outer planets. We quantify the effects that outer giant planet companions have on collisions and the planet accretion process. We focus on Earth-analogs that form in each system and explore how giant planets influence the relative frequency of giant impacts occurring at late times and the delivery of volitiles. This work has important implications for determining the frequency of habitable planets.

  3. The terrestrial cratering record. II - The crater production rate

    NASA Technical Reports Server (NTRS)

    Grieve, R. A. F.; Dence, M. R.

    1979-01-01

    The terrestrial crater production rate is estimated from a compilation of the locations and ages of proven and probable terrestrial impact craters and compared with that calculated from astronomical observations and for other planets. The estimated size-frequency distribution of craters greater than 20 km in diameter formed during the Phanerozoic, a -2 power law, is similar to the distributions of lunar and Martian craters. The North American and East European cratons are estimated to have cratering rates of craters greater than 20 km of 0.36 x 10 to the -14/sq km yr and 0.33 x 10 to the -14/sq km yr, respectively, in good agreement with previous estimates and observations of Apollo bodies. Comparisons with the lunar rate indicate that the lunar and terrestrial rates overlap if the cratering flux had been constant over the last 3.4 billion years, however if a constant rate was not reached until 3.0 to 2.5 billion years ago, the lunar rate would have been half that of the terrestrial rate.

  4. Photochemistry of Terrestrial Exoplanet Atmospheres

    NASA Astrophysics Data System (ADS)

    Hu, Renyu; Seager, S.

    2013-01-01

    Terrestrial exoplanet atmospheres require photochemistry for their study. This is because the steady state composition depends critically on the component gas sources (surface emission) and sinks (chemical reactions initiated by UV photolysis). For my Ph.D. research I have developed a comprehensive photochemistry model for terrestrial exoplanet atmospheres from the ground up, which includes 111 molecules and aerosols made of C, H, O, N, S elements, and more than 800 chemical reactions linking them. With updated numerical algorithms, the photochemistry model has desirable features for exoplanet exploration, notably the capacity of treating both reduced and oxidized atmospheres, the elimination of the need of fine-tuned initial conditions, and the flexibility of choosing a subset of chemical species and chemical reactions for the computation. Using the photochemistry model, I provided benchmark atmospheric composition models for reducing, weakly oxidizing, and highly oxidizing atmospheres on terrestrial exoplanets; I systemized the short-lived nature of sulfur gases on virtually all types of terrestrial exoplanet atmospheres; I revisited O2 as the remote-sensing probe of biotic photosynthesis and found a potential false positive in high CO2 atmospheres without surface emission of reducing gases (e.g., H2 and CH4); and I provided atmosphere models to propose NH3 as a new biosignature gas in hydrogen-rich atmospheres. I have also extended the photochemistry model to the regime of thick atmospheres (at depths of which thermochemical equilibrium can be effectively achieved), and summarized a zoo of super-Earths including water planets, hydrocarbon planets, and even oxygen planets depending on the C-H-O elemental abundances of their atmospheres.

  5. Workshop on Oxygen in the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This volume contains abstracts that have been accepted for presentation at the Workshop on Oxygen in the Terrestrial Planets, July 20-23,2004, Santa Fe, New Mexico. The contents include: 1) Experimental Constraints on Oxygen and Other Light Element Partitioning During Planetary Core Formation; 2) In Situ Determination of Fe(3+)/SigmaFe of Spinels by Electron Microprobe: An Evaluation of the Flank Method; 3) The Effect of Oxygen Fugacity on Large-Strain Deformation and Recrystallization of Olivine; 4) Plagioclase-Liquid Trace Element Oxygen Barometry and Oxygen Behaviour in Closed and Open System Magmatic Processes; 5) Core Formation in the Earth: Constraints from Ni and Co; 6) Oxygen Isotopic Compositions of the Terrestrial Planets; 7) The Effect of Oxygen Fugacity on Electrical Conduction of Olivine and Implications for Earth s Mantle; 8) Redox Chemical Diffusion in Silicate Melts: The Impact of the Semiconductor Condition; 9) Ultra-High Temperature Effects in Earth s Magma Ocean: Pt and W Partitioning; 10) Terrestrial Oxygen and Hydrogen Isotope Variations: Primordial Values, Systematics, Subsolidus Effects, Planetary Comparisons, and the Role of Water; 11) Redox State of the Moon s Interior; 12) How did the Terrestrial Planets Acquire Their Water?; 13) Molecular Oxygen Mixing Ratio and Its Seasonal Variability in the Martian Atmosphere; 14) Exchange Between the Atmosphere and the Regolith of Mars: Discussion of Oxygen and Sulfur Isotope Evidence; 15) Oxygen and Hydrogen Isotope Systematics of Atmospheric Water Vapor and Meteoric Waters: Evidence from North Texas; 16) Implications of Isotopic and Redox Heterogeneities in Silicate Reservoirs on Mars; 17) Oxygen Isotopic Variation of the Terrestrial Planets; 18) Redox Exchanges in Hydrous Magma; 19) Hydrothermal Systems on Terrestrial Planets: Lessons from Earth; 20) Oxygen in Martian Meteorites: A Review of Results from Mineral Equilibria Oxybarometers; 21) Non-Linear Fractionation of Oxygen Isotopes Implanted in Lunar Metal Grains: Solar, Lunar or Terrestrial Origin? 22) Isotopic Zoning in the Inner Solar System; 23) Redox Conditions on Small Bodies; 24) Determining the Oxygen Fugacity of Lunar Pyroclastic Glasses Using Vanadium Valence - An Update; 25) Mantle Redox Evolution and the Rise of Atmospheric O2; 26) Variation of Kd for Fe-Mg Exchange Between Olivine and Melt for Compositions Ranging from Alkaline Basalt to Rhyolite; 27) Determining the Partial Pressure of Oxygen (PO,) in Solutions on Mars; 28) The Influence of Oxygen Environment on Kinetic Properties of Silicate Rocks and Minerals; 29) Redox Evolution of Magmatic Systems; 30) The Constancy of Upper Mantlefo, Through Time Inferred from V/Sc Ratios in Basalts: Implications for the Rise in Atmospheric 0 2; 31) Nitrogen Solubility in Basaltic Melt. Effects of Oxygen Fugacity, Melt Composition and Gas Speciation; 32) Oxygen Isotope Anomalies in the Atmospheres of Earth and Mars; 33) The Effect of Oxygen Fugacity on Interdiffusion of Iron and Magnesium in Magnesiowiistite 34) The Calibration of the Pyroxene Eu-Oxybarometer for the Martian Meteorites; 35) The Europium Oxybarometer: Power and Pitfalls; 36) Oxygen Fugacity of the Martian Mantle from PigeoniteMelt Partitioning of Samarium, Europium and Gadolinium; 37) Oxidation-Reduction Processes on the Moon: Experimental Verification of Graphite Oxidation in the Apollo 17 Orange Glasses; 38) Oxygen and Core Formation in the Earth; 39) Geologic Record of the Atmospheric Sulfur Chemistry Before the Oxygenation of the Early Earth s Atmosphere; 40) Comparative Planetary Mineralogy: V/(CrCAl) Systematics in Chromite as an Indicator of Relative Oxygen Fugacity; 41) How Well do Sulfur Isotopes Constrain Oxygen Abundance in the Ancient Atmospheres? 42) Experimental Constraints on the Oxygen Isotope (O-18/ O-16) Fractionation in the Ice vapor and Adsorbant vapor Systems of CO2 at Conditions Relevant to the Surface of Mars; 43) Micro-XANES Measurements on Experimental Spinels andhe Oxidation State of Vanadium in Spinel-Melt Pairs; 44) Testing the Magma Ocean Hypothesis Using Metal-Silicate Partitioning of Te, Se and S; 45) Solubility of Oxygen in Liquid Iron at High Pressure and Consequences for the Early Differentiation of Earth and Mars Metallic Liquid Segregation in Planetesimals; 46) Oxygen Fugacity of Lunar Basalts and the Lunar Mantle. Range of fo2 and the Effectiveness of Oxybarometers; 47) Thermodynamic Study of Dissociation Processes of Molecular Oxygen in Vapor over Oxide Compounds; 48) Oxygen Profile of a Thermo-Haliophilic Community in the Badwater Salt Flat; 49) Oxygen Barometry Using Synchrotron MicroXANES of Vanadium; 50) Mass-Independent Isotopic Fractionation of Sulfur from Sulfides in the Huronian Supergroup, Canada; 51) Mass Independent Isotopes and Applications to Planetary Atmospheres; 52) Electrical Conductivity, Oxygen Fugacity, and Mantle Materials; 53) Crustal Evolution and Maturation on Earth: Oxygen Isotope Evidence; 54) The Oxygen Isotope Composition of the Moon: Implications for Planet Formation; 55) Oxygen Isotope Composition of Eucrites and Implications for the Formation of Crust on the HED Parent Body; and 56) The Role of Water in Determining the Oxygen Isotopic Composition of Planets.

  6. Spatial Vision in Bombus terrestris.

    PubMed

    Chakravarthi, Aravin; Baird, Emily; Dacke, Marie; Kelber, Almut

    2016-01-01

    Bombus terrestris is one of the most commonly used insect models to investigate visually guided behavior and spatial vision in particular. Two fundamental measures of spatial vision are spatial resolution and contrast sensitivity. In this study, we report the threshold of spatial resolution in B. terrestris and characterize the contrast sensitivity function of the bumblebee visual system for a dual choice discrimination task. We trained bumblebees in a Y-maze experimental set-up to associate a vertical sinusoidal grating with a sucrose reward, and a horizontal grating with absence of a reward. Using a logistic psychometric function, we estimated a resolution threshold of 0.21 cycles deg(-1) of visual angle. This resolution is in the same range but slightly lower than that found in honeybees (Apis mellifera and A. cerana) and another bumblebee species (B. impatiens). We also found that the contrast sensitivity of B. terrestris was 1.57 for the spatial frequency 0.090 cycles deg(-1) and 1.26 for 0.18 cycles deg(-1). PMID:26912998

  7. Arsenic speciation of terrestrial invertebrates.

    PubMed

    Moriarty, Maeve M; Koch, Iris; Gordon, Robert A; Reimer, Kenneth J

    2009-07-01

    The distribution and chemical form (speciation) of arsenic in terrestrial food chains determines both the amount of arsenic available to higher organisms, and the toxicity of this metalloid in affected ecosystems. Invertebrates are part of complex terrestrial food webs. This paper provides arsenic concentrations and arsenic speciation profiles for eight orders of terrestrial invertebrates collected at three historical gold mine sites and one background site in Nova Scotia, Canada. Total arsenic concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS), were dependent upon the classification of invertebrate. Arsenic species were determined by high-performance liquid chromatography (HPLC) ICP-MS and X-ray absorption spectroscopy (XAS). Invertebrates were found by HPLC ICP-MS to contain predominantly arsenite and arsenate in methanol/water extracts, while XAS revealed that most arsenic is bound to sulfur in vivo. Examination of the spatial distribution of arsenic within an ant tissue highlighted the differences between exogenous and endogenous arsenic, as well as the extent to which arsenic is transformed upon ingestion. Similar arsenic speciation patterns for invertebrate groups were observed across sites. Trace amounts of arsenobetaine and arsenocholine were identified in slugs, ants, and spiders. PMID:19673270

  8. Spatial Vision in Bombus terrestris

    PubMed Central

    Chakravarthi, Aravin; Baird, Emily; Dacke, Marie; Kelber, Almut

    2016-01-01

    Bombus terrestris is one of the most commonly used insect models to investigate visually guided behavior and spatial vision in particular. Two fundamental measures of spatial vision are spatial resolution and contrast sensitivity. In this study, we report the threshold of spatial resolution in B. terrestris and characterize the contrast sensitivity function of the bumblebee visual system for a dual choice discrimination task. We trained bumblebees in a Y-maze experimental set-up to associate a vertical sinusoidal grating with a sucrose reward, and a horizontal grating with absence of a reward. Using a logistic psychometric function, we estimated a resolution threshold of 0.21 cycles deg−1 of visual angle. This resolution is in the same range but slightly lower than that found in honeybees (Apis mellifera and A. cerana) and another bumblebee species (B. impatiens). We also found that the contrast sensitivity of B. terrestris was 1.57 for the spatial frequency 0.090 cycles deg−1 and 1.26 for 0.18 cycles deg−1. PMID:26912998

  9. Arsenic Speciation of Terrestrial Invertebrates

    SciTech Connect

    Moriarty, M.M.; Koch, I.; Gordon, R.A.; Reimer, K.J. ); )

    2009-07-01

    The distribution and chemical form (speciation) of arsenic in terrestrial food chains determines both the amount of arsenic available to higher organisms, and the toxicity of this metalloid in affected ecosystems. Invertebrates are part of complex terrestrial food webs. This paper provides arsenic concentrations and arsenic speciation profiles for eight orders of terrestrial invertebrates collected at three historical gold mine sites and one background site in Nova Scotia, Canada. Total arsenic concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS), were dependent upon the classification of invertebrate. Arsenic species were determined by high-performance liquid chromatography (HPLC) ICP-MS and X-ray absorption spectroscopy (XAS). Invertebrates were found by HPLC ICP-MS to contain predominantly arsenite and arsenate in methanol/water extracts, while XAS revealed that most arsenic is bound to sulfur in vivo. Examination of the spatial distribution of arsenic within an ant tissue highlighted the differences between exogenous and endogenous arsenic, as well as the extent to which arsenic is transformed upon ingestion. Similar arsenic speciation patterns for invertebrate groups were observed across sites. Trace amounts of arsenobetaine and arsenocholine were identified in slugs, ants, and spiders.

  10. Global Climate Models of the Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Forget, F.; Lebonnois, S.

    On the basis of the global climate models (GCMs) originally developed for Earth, several teams around the world have been able to develop GCMs for the atmospheres of the other terrestrial bodies in our solar system: Venus, Mars, Titan, Triton, and Pluto. In spite of the apparent complexity of climate systems and meteorology, GCMs are based on a limited number of equations. In practice, relatively complete climate simulators can be developed by combining a few components such as a dynamical core, a radiative transfer solver, a parameterization of turbulence and convection, a thermal ground model, and a volatile phase change code, possibly completed by a few specific schemes. It can be shown that many of these GCM components are "universal" so that we can envisage building realistic climate models for any kind of terrestrial planets and atmospheres that we can imagine. Such a tool is useful for conducting scientific investigations on the possible climates of terrestrial extrasolar planets, or to study past environments in the solar system. The ambition behind the development of GCMs is high: The ultimate goal is to build numerical simulators based only on universal physical or chemical equations, yet able to reproduce or predict all the available observations on a given planet, without any ad hoc forcing. In other words, we aim to virtually create in our computers planets that "behave" exactly like the actual planets themselves. In reality, of course, nature is always more complex than expected, but we learn a lot in the process. In this chapter we detail some lessons learned in the solar system: In many cases, GCMs work. They have been able to simulate many aspects of planetary climates without difficulty. In some cases, however, problems have been encountered, sometimes simply because a key process has been forgotten in the model or is not yet correctly parameterized, but also because sometimes the climate regime seems to be result of a subtle balance between processes that remain highly model sensitive, or are the subject of positive feedback and unstability. In any case, building virtual planets with GCMs, in light of the observations obtained by spacecraft or from Earth, is a true scientific endeavor that can teach us a lot about the complex nature of climate systems.

  11. BOOK REVIEW: Black Holes, Cosmology and Extra Dimensions Black Holes, Cosmology and Extra Dimensions

    NASA Astrophysics Data System (ADS)

    Frolov, Valeri P.

    2013-10-01

    The book Black holes, Cosmology and Extra Dimensions written by Kirill A Bronnikov and Sergey G Rubin has been published recently by World Scientific Publishing Company. The authors are well known experts in gravity and cosmology. The book is a monograph, a considerable part of which is based on the original work of the authors. Their original point of view on some of the problems makes the book quite interesting, covering a variety of important topics of the modern theory of gravity, astrophysics and cosmology. It consists of 11 chapters which are organized in three parts. The book starts with an introduction, where the authors briefly discuss the main ideas of General Relativity, giving some historical remarks on its development and application to cosmology, and mentioning some more recent subjects such as brane worlds, f(R)-theories and gravity in higher dimensions. Part I of the book is called 'Gravity'. Chapters two and three are devoted to the Einstein equations and their spherical symmetric black hole solutions. This material is quite standard and can be found in practically any book on General Relativity. A brief summary of the Kerr metric and black hole thermodynamics are given in chapter four. The main part of this chapter is devoted to spherically symmetric black holes in non-Einstein gravity (with scalar and phantom fields), black holes with regular interior, and black holes in brane worlds. Chapters five and six are mainly dedicated to wormholes and the problem of their stability. Part II (Cosmology) starts with discussion of the Friedmann-Robertson-Walker and de Sitter solutions of the Einstein equations and their properties. It follows by describing a `big picture' of the modern cosmology (inflation, post-inflationary reheating, the radiation-dominated and matter-dominated states, and modern stage of the (secondary) inflation). The authors explain how the inflation models allow one to solve many of the long-standing problems of cosmology, such as flatness of the Universe, the horizon problem and isotropy of cosmological microwave background. All this material is covered in chapter seven. Chapter eight contains brief discussion of several popular inflation models. Chapter nine is devoted to the problem of the large-scale structure formation from initial quantum vacuum fluctuation during the inflation and the spectrum of the density fluctuations. It also contains remarks on the baryonic asymmetry of the Universe, baryogenesis and primordial black holes. Part III covers the material on extra dimensions. It describes how Einstein gravity is modified in the presence of one or more additional spatial dimensions and how these extra dimensions are compactified in the Kaluza-Klein scheme. The authors also discuss how extra dimensions may affect low energy physics. They present examples of higher-dimensional generalizations of the gravity with higher-in-curvature corrections and discuss a possible mechanism of self-stabilization of an extra space. A considerable part of the chapter 10 is devoted to cosmological models with extra dimensions. In particular, the authors discuss how extra dimensions can modify 'standard' inflation models. At the end of this chapter they make several remarks on a possible relation of the value of fundamental constants in our universe with the existence of extra dimensions. Finally, in chapter 11 they demonstrate that several observable properties of the Universe are closely related with the special value of the fundamental physical constants and their fine tuning. They give interesting examples of such fine tuning and summarize many other cases. The book ends with discussion of a so-called 'cascade birth of universes in multidimensional spaces' model, proposed by one of the authors. As is evident from this brief summary of topics presented in the book, many interesting areas of modern gravity and cosmology are covered. However, since the subject is so wide, this inevitably implies that the selection of the topics and level of their presentation in many cases reflects the authors' own preferences. As a result, several important subjects on black holes, cosmology and extra dimensions, widely discussed in the modern literature, are not covered by the book. For example, a reader will not find discussion of non-spherically symmetric higher dimensional black holes which are either non-trivial generalization of the Kerr black holes, or even have a non-spherical topology of the horizon (black rings, black strings and so on). The book does not contain any information on supersymmetric black holes, black branes solutions and their properties. This list can easily be continued (black hole perturbations, gravitational radiation from binary black hole coalescence, cosmology in massive gravity and Hořava-Lifshitz models, etc). However the number of publications connected with the title of the book is so huge now, that it is practically impossible to cover all of them in a single book. Some selection of topics is inevitable. To summarize, I think that the authors did a great job and the book will find its readers. It might be interesting for researchers working in theoretical physics, astrophysics and cosmology. I do not think that it would be very helpful as a textbook for students, although it contains a lot of interesting material which can be used by students for additional reading connected with the basic university courses on gravity and cosmology. It might be also useful to students for their term paper projects and presentations.

  12. Error bounds from extra precise iterative refinement

    SciTech Connect

    Demmel, James; Hida, Yozo; Kahan, William; Li, Xiaoye S.; Mukherjee, Soni; Riedy, E. Jason

    2005-02-07

    We present the design and testing of an algorithm for iterative refinement of the solution of linear equations, where the residual is computed with extra precision. This algorithm was originally proposed in the 1960s [6, 22] as a means to compute very accurate solutions to all but the most ill-conditioned linear systems of equations. However two obstacles have until now prevented its adoption in standard subroutine libraries like LAPACK: (1) There was no standard way to access the higher precision arithmetic needed to compute residuals, and (2) it was unclear how to compute a reliable error bound for the computed solution. The completion of the new BLAS Technical Forum Standard [5] has recently removed the first obstacle. To overcome the second obstacle, we show how a single application of iterative refinement can be used to compute an error bound in any norm at small cost, and use this to compute both an error bound in the usual infinity norm, and a componentwise relative error bound. We report extensive test results on over 6.2 million matrices of dimension 5, 10, 100, and 1000. As long as a normwise (resp. componentwise) condition number computed by the algorithm is less than 1/max{l_brace}10,{radical}n{r_brace} {var_epsilon}{sub w}, the computed normwise (resp. componentwise) error bound is at most 2 max{l_brace}10,{radical}n{r_brace} {center_dot} {var_epsilon}{sub w}, and indeed bounds the true error. Here, n is the matrix dimension and w is single precision roundoff error. For worse conditioned problems, we get similarly small correct error bounds in over 89.4% of cases.

  13. Lorentz Violation in Warped Extra Dimensions

    SciTech Connect

    Rizzo, Thomas G.; /SLAC

    2011-08-11

    Higher dimensional theories which address some of the problematic issues of the Standard Model(SM) naturally involve some form of D = 4 + n-dimensional Lorentz invariance violation (LIV). In such models the fundamental physics which leads to, e.g., field localization, orbifolding, the existence of brane terms and the compactification process all can introduce LIV in the higher dimensional theory while still preserving 4-d Lorentz invariance. In this paper, attempting to capture some of this physics, we extend our previous analysis of LIV in 5-d UED-type models to those with 5- d warped extra dimensions. To be specific, we employ the 5-d analog of the SM Extension of Kostelecky et al. which incorporates a complete set of operators arising from spontaneous LIV. We show that while the response of the bulk scalar, fermion and gauge fields to the addition of LIV operators in warped models is qualitatively similar to what happens in the flat 5-d UED case, the gravity sector of these models reacts very differently than in flat space. Specifically, we show that LIV in this warped case leads to a non-zero bulk mass for the 5-d graviton and so the would-be zero mode, which we identify as the usual 4-d graviton, must necessarily become massive. The origin of this mass term is the simultaneous existence of the constant non-zero AdS{sub 5} curvature and the loss of general co-ordinate invariance via LIV in the 5-d theory. Thus warped 5-d models with LIV in the gravity sector are not phenomenologically viable.

  14. Girls and war: an extra vulnerability.

    PubMed

    Black, M

    1998-01-01

    It is no longer possible to consider the raping of girls as an isolated atrocity of war. In Uganda, guerrilla forces have kidnapped 6000-10,000 children and have forced the "most desirable" girls to become "wives" of warlords. Girls who manage to escape are deeply traumatized and suffer ill health as well as possible social ostracism. In refugee camps, recognition that adolescent girls face special risks of rape and of engaging in the informal prostitution that may expose them to HIV/AIDS has led to the introduction of new measures to increase female security. Families in refugee camps in Burundi and Somalia protect female honor by submitting their daughters to very early marriage, which also abuses the girls' rights. Girls conscripted to military groups are forced to transport materials, cook, or help loot villages. In conditions of war, even girls who remain at home protected by their families must assume extra responsibilities, especially if men go off to fight leaving women with the agricultural and livestock burdens. Girls will be the first children withdrawn from school to help keep the household afloat. Girls and women are also expected to tend those wounded by the very war that destroys the health care services that are vital to meet women's reproductive needs. Efforts are being made to identify rape as a specific war crime, and these efforts should be extended to the kidnapping and forced recruitment of children into combat roles. Moral codes must be reestablished, even if they are only nominal at present. PMID:12321764

  15. The Oldest Caseid Synapsid from the Late Pennsylvanian of Kansas, and the Evolution of Herbivory in Terrestrial Vertebrates

    PubMed Central

    Reisz, Robert R.; Fröbisch, Jörg

    2014-01-01

    The origin and early evolution of amniotes (fully terrestrial vertebrates) led to major changes in the structure and hierarchy of terrestrial ecosystems. The first appearance of herbivores played a pivotal role in this transformation. After an early bifurcation into Reptilia and Synapsida (including mammals) 315 Ma, synapsids dominated Paleozoic terrestrial vertebrate communities, with the herbivorous caseids representing the largest vertebrates on land. Eocasea martini gen. et sp. nov., a small carnivorous caseid from the Late Carboniferous, extends significantly the fossil record of Caseidae, and permits the first clade-based study of the origin and initial evolution of herbivory in terrestrial tetrapods. Our results demonstrate for the first time that large caseid herbivores evolved from small, non-herbivorous caseids. This pattern is mirrored by three other clades, documenting multiple, independent, but temporally staggered origins of herbivory and increase in body size among early terrestrial tetrapods, leading to patterns consistent with modern terrestrial ecosystem. PMID:24739998

  16. The oldest caseid synapsid from the Late Pennsylvanian of Kansas, and the evolution of herbivory in terrestrial vertebrates.

    PubMed

    Reisz, Robert R; Fröbisch, Jörg

    2014-01-01

    The origin and early evolution of amniotes (fully terrestrial vertebrates) led to major changes in the structure and hierarchy of terrestrial ecosystems. The first appearance of herbivores played a pivotal role in this transformation. After an early bifurcation into Reptilia and Synapsida (including mammals) 315 Ma, synapsids dominated Paleozoic terrestrial vertebrate communities, with the herbivorous caseids representing the largest vertebrates on land. Eocasea martini gen. et sp. nov., a small carnivorous caseid from the Late Carboniferous, extends significantly the fossil record of Caseidae, and permits the first clade-based study of the origin and initial evolution of herbivory in terrestrial tetrapods. Our results demonstrate for the first time that large caseid herbivores evolved from small, non-herbivorous caseids. This pattern is mirrored by three other clades, documenting multiple, independent, but temporally staggered origins of herbivory and increase in body size among early terrestrial tetrapods, leading to patterns consistent with modern terrestrial ecosystem. PMID:24739998

  17. Transcriptome analysis of primary bovine extra-embryonic cultured cells

    PubMed Central

    Degrelle, Sverine A.

    2015-01-01

    The dataset described in this article pertains to the article by Hue et al. (2015) entitled Primary bovine extra-embryonic cultured cells: A new resource for the study of in vivo peri-implanting phenotypes and mesoderm formation [1]. In mammals, extra-embryonic tissues are essential to support not only embryo patterning but also embryo survival, especially in late implanting species. These tissues are composed of three cell types: trophoblast (bTCs), endoderm (bXECs) and mesoderm (bXMCs). Until now, it is unclear how these cells interact. In this study, we have established primary cell cultures of extra-embryonic tissues from bovine embryos collected at day-18 after artificial insemination. We used our homemade bovine 10K array (GPL7417) to analyze the gene expression profiles of these primary extra-embryonic cultured cells compared to the corresponding cells from in vivo micro-dissected embryos. Here, we described the experimental design, the isolation of bovine extra-embryonic cell types as well as the microarray expression analysis. The dataset has been deposited in Gene Expression Omnibus (GEO) (accession number GSE52967). Finally, these primary cell cultures were a powerful tool to start studying their cellular properties, and will further allow in vitro studies on cellular interactions among extra-embryonic tissues, and potentially between extra-embryonic vs embryonic tissues. PMID:26697347

  18. Transcriptome analysis of primary bovine extra-embryonic cultured cells.

    PubMed

    Degrelle, Séverine A

    2015-12-01

    The dataset described in this article pertains to the article by Hue et al. (2015) entitled "Primary bovine extra-embryonic cultured cells: A new resource for the study of in vivo peri-implanting phenotypes and mesoderm formation" [1]. In mammals, extra-embryonic tissues are essential to support not only embryo patterning but also embryo survival, especially in late implanting species. These tissues are composed of three cell types: trophoblast (bTCs), endoderm (bXECs) and mesoderm (bXMCs). Until now, it is unclear how these cells interact. In this study, we have established primary cell cultures of extra-embryonic tissues from bovine embryos collected at day-18 after artificial insemination. We used our homemade bovine 10K array (GPL7417) to analyze the gene expression profiles of these primary extra-embryonic cultured cells compared to the corresponding cells from in vivo micro-dissected embryos. Here, we described the experimental design, the isolation of bovine extra-embryonic cell types as well as the microarray expression analysis. The dataset has been deposited in Gene Expression Omnibus (GEO) (accession number GSE52967). Finally, these primary cell cultures were a powerful tool to start studying their cellular properties, and will further allow in vitro studies on cellular interactions among extra-embryonic tissues, and potentially between extra-embryonic vs embryonic tissues. PMID:26697347

  19. A comparative analysis of dispersal syndromes in terrestrial and semi-terrestrial animals.

    PubMed

    Stevens, Virginie M; Whitmee, Sarah; Le Galliard, Jean-François; Clobert, Jean; Böhning-Gaese, Katrin; Bonte, Dries; Brändle, Martin; Matthias Dehling, D; Hof, Christian; Trochet, Audrey; Baguette, Michel

    2014-08-01

    Dispersal, the behaviour ensuring gene flow, tends to covary with a number of morphological, ecological and behavioural traits. While species-specific dispersal behaviours are the product of each species' unique evolutionary history, there may be distinct interspecific patterns of covariation between dispersal and other traits ('dispersal syndromes') due to their shared evolutionary history or shared environments. Using dispersal, phylogeny and trait data for 15 terrestrial and semi-terrestrial animal Orders (> 700 species), we tested for the existence and consistency of dispersal syndromes across species. At this taxonomic scale, dispersal increased linearly with body size in omnivores, but decreased above a critical length in herbivores and carnivores. Species life history and ecology significantly influenced patterns of covariation, with higher phylogenetic signal of dispersal in aerial dispersers compared with ground dwellers and stronger evidence for dispersal syndromes in aerial dispersers and ectotherms, compared with ground dwellers and endotherms. Our results highlight the complex role of dispersal in the evolution of species life-history strategies: good dispersal ability was consistently associated with high fecundity and survival, and in aerial dispersers it was associated with early maturation. We discuss the consequences of these findings for species evolution and range shifts in response to future climate change. PMID:24915998

  20. Extra Solar Planetary Imaging Coronagraph and Science Requirements for the James Webb Telescope Observatory

    NASA Technical Reports Server (NTRS)

    Clampin, Mark

    2004-01-01

    1) Extra solar planetary imaging coronagraph. Direct detection and characterization of Jovian planets, and other gas giants, in orbit around nearby stars is a necessary precursor to Terrestrial Planet Finder 0 in order to estimate the probability of Terrestrial planets in our stellar neighborhood. Ground based indirect methods are biased towards large close in Jovian planets in solar systems unlikely io harbor Earthlike planets. Thus to estimate the relative abundances of terrestrial planets and to determine optimal observing strategies for TPF a pathfinder mission would be desired. The Extra-Solar Planetary Imaging Coronagraph (EPIC) is such a pathfinder mission. Upto 83 stellar systems are accessible with a 1.5 meter unobscured telescope and coronagraph combination located at the Earth-Sun L2 point. Incorporating radiometric and angular resolution considerations show that Jovians could be directly detected (5 sigma) in the 0.5 - 1.0 micron band outside of an inner working distance of 5/D with integration times of -10 - 100 hours per observation. The primary considerations for a planet imager are optical wavefront quality due to manufacturing, alignment, structural and thermal considerations. pointing stability and control, and manufacturability of coronagraphic masks and stops to increase the planetary-to- stellar contrast and mitigate against straylight. Previously proposed coronagraphic concepts are driven to extreme tolerances. however. we have developed and studied a mission, telescope and coronagraphic detection concept, which is achievable in the time frame of a Discovery class NASA mission. 2) Science requirements for the James Webb Space Telescope observatory. The James Webb Space Observatory (JWST) is an infrared observatory, which will be launched in 201 1 to an orbit at L2. JWST is a segmented, 18 mirror segment telescope with a diameter of 6.5 meters, and a clear aperture of 25 mA2. The telescope is designed to conduct imaging and spectroscopic observations from 0.6-27 microns. The primary mirror find and understand predicted first light objects, observe galaxies back to their earliest precursors so that we can understand their growth and evolution, unravel the birth and early evolution of stars and planetary systems, and study planetary systems and the origins of life. In this paper we discuss the science goals for JWST in the context of the performance requirements they levy on the observatory.

  1. Axion arising from warped extra-dimensional gauge fields

    SciTech Connect

    Burnier, Y.; Kuehnel, F.

    2011-06-01

    We present a connection between two known solutions to the strong-CP problem: the standard introduction of axions and the extra-dimensional one, relying on topological arguments. Using an equivalent lower-dimensional setup with a warped extra dimension but without adding any new fields, it is shown that an additional light degree of freedom appears. Like an axion, it couples to the topological charge density via fermionic loop corrections. Its decay constant is related to the geometry of the extra dimension and is suppressed by the warping scale.

  2. Search for large extra dimensions in dielectron and diphoton production.

    PubMed

    Abbott, B; Abolins, M; Abramov, V; Acharya, B S; Adams, D L; Adams, M; Alves, G A; Amos, N; Anderson, E W; Baarmand, M M; Babintsev, V V; Babukhadia, L; Baden, A; Baldin, B; Balm, P W; Banerjee, S; Bantly, J; Barberis, E; Baringer, P; Bartlett, J F; Bassler, U; Bean, A; Begel, M; Belyaev, A; Beri, S B; Bernardi, G; Bertram, I; Besson, A; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Bhattacharjee, M; Blazey, G; Blessing, S; Boehnlein, A; Bojko, N I; Borcherding, F; Brandt, A; Breedon, R; Briskin, G; Brock, R; Brooijmans, G; Bross, A; Buchholz, D; Buehler, M; Buescher, V; Burtovoi, V S; Butler, J M; Canelli, F; Carvalho, W; Casey, D; Casilum, Z; Castilla-Valdez, H; Chakraborty, D; Chan, K M; Chekulaev, S V; Cho, D K; Choi, S; Chopra, S; Christenson, J H; Chung, M; Claes, D; Clark, A R; Cochran, J; Coney, L; Connolly, B; Cooper, W E; Coppage, D; Cummings, M A; Cutts, D; Dahl, O I; Davis, G A; Davis, K; De, K; Del Signore, K; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Di Loreto, G; Doulas, S; Draper, P; Ducros, Y; Dudko, L V; Duensing, S; Dugad, S R; Dyshkant, A; Edmunds, D; Ellison, J; Elvira, V D; Engelmann, R; Eno, S; Eppley, G; Ermolov, P; Eroshin, O V; Estrada, J; Evans, H; Evdokimov, V N; Fahland, T; Feher, S; Fein, D; Ferbel, T; Fisk, H E; Fisyak, Y; Flattum, E; Fleuret, F; Fortner, M; Frame, K C; Fuess, S; Gallas, E; Galyaev, A N; Gartung, P; Gavrilov, V; Genik, R J; Genser, K; Gerber, C E; Gershtein, Y; Gibbard, B; Gilmartin, R; Ginther, G; Gómez, B; Gómez, G; Goncharov, P I; González Solís, J L; Gordon, H; Goss, L T; Gounder, K; Goussiou, A; Graf, N; Graham, G; Grannis, P D; Green, J A; Greenlee, H; Grinstein, S; Groer, L; Grudberg, P; Grünendahl, S; Gupta, A; Gurzhiev, S N; Gutierrez, G; Gutierrez, P; Hadley, N J; Haggerty, H; Hagopian, S; Hagopian, V; Hahn, K S; Hall, R E; Hanlet, P; Hansen, S; Hauptman, J M; Hays, C; Hebert, C; Hedin, D; Heinson, A P; Heintz, U; Heuring, T; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoftun, J S; Hou, S; Huang, Y; Ito, A S; Jerger, S A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jones, M; Jöstlein, H; Juste, A; Kahn, S; Kajfasz, E; Karmanov, D; Karmgard, D; Kehoe, R; Kim, S K; Klima, B; Klopfenstein, C; Knuteson, B; Ko, W; Kohli, J M; Kostritskiy, A V; Kotcher, J; Kotwal, A V; Kozelov, A V; Kozlovsky, E A; Krane, J; Krishnaswamy, M R; Krzywdzinski, S; Kubantsev, M; Kuleshov, S; Kulik, Y; Kunori, S; Kuznetsov, V E; Landsberg, G; Leflat, A; Lehner, F; Li, J; Li, Q Z; Lima, J G; Lincoln, D; Linn, S L; Linnemann, J; Lipton, R; Lucotte, A; Lueking, L; Lundstedt, C; Maciel, A K; Madaras, R J; Manankov, V; Mao, H S; Marshall, T; Martin, M I; Martin, R D; Mauritz, K M; May, B; Mayorov, A A; McCarthy, R; McDonald, J; McMahon, T; Melanson, H L; Meng, X C; Merkin, M; Merritt, K W; Miao, C; Miettinen, H; Mihalcea, D; Mincer, A; Mishra, C S; Mokhov, N; Mondal, N K; Montgomery, H E; Moore, R W; Mostafa, M; da Motta, H; Nagy, E; Nang, F; Narain, M; Narasimham, V S; Neal, H A; Negret, J P; Negroni, S; Norman, D; Oesch, L; Oguri, V; Olivier, B; Oshima, N; Padley, P; Pan, L J; Para, A; Parashar, N; Partridge, R; Parua, N; Paterno, M; Patwa, A; Pawlik, B; Perkins, J; Peters, M; Peters, O; Piegaia, R; Piekarz, H; Pope, B G; Popkov, E; Prosper, H B; Protopopescu, S; Qian, J; Quintas, P Z; Raja, R; Rajagopalan, S; Ramberg, E; Rapidis, P A; Reay, N W; Reucroft, S; Rha, J; Rijssenbeek, M; Rockwell, T; Roco, M; Rubinov, P; Ruchti, R; Rutherfoord, J; Santoro, A; Sawyer, L; Schamberger, R D; Schellman, H; Schwartzman, A; Sculli, J; Sen, N; Shabalina, E; Shankar, H C; Shivpuri, R K; Shpakov, D; Shupe, M; Sidwell, R A; Simak, V; Singh, H; Singh, J B; Sirotenko, V; Slattery, P; Smith, E; Smith, R P; Snihur, R; Snow, G R; Snow, J; Snyder, S; Solomon, J; Sorín, V; Sosebee, M; Sotnikova, N; Soustruznik, K; Souza, M; Stanton, N R; Steinbrück, G; Stephens, R W; Stevenson, M L; Stichelbaut, F; Stoker, D; Stolin, V; Stoyanova, D A; Strauss, M; Streets, K; Strovink, M; Stutte, L; Sznajder, A; Taylor, W; Tentindo-Repond, S; Thompson, J; Toback, D; Tripathi, S M; Trippe, T G; Turcot, A S; Tuts, P M; van Gemmeren, P; Vaniev, V; Van Kooten, R; Varelas, N; Volkov, A A; Vorobiev, A P; Wahl, H D; Wang, H; Wang, Z; Warchol, J; Watts, G; Wayne, M; Weerts, H; White, A; White, J T; Whiteson, D; Wightman, J A; Wijngaarden, D A; Willis, S; Wimpenny, S J; Wirjawan, J V; Womersley, J; Wood, D R; Yamada, R; Yamin, P; Yasuda, T; Yip, K; Youssef, S; Yu, J; Yu, Z; Zanabria, M; Zheng, H; Zhou, Z; Zhu, Z H; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G; Zylberstejn, A

    2001-02-12

    We report a search for effects of large extra spatial dimensions in pp collisions at a center-of-mass energy of 1.8 TeV with the D0 detector, using events containing a pair of electrons or photons. The data are in good agreement with the expected background and do not exhibit evidence for large extra dimensions. We set the most restrictive lower limits to date, at the 95% C.L. on the effective Planck scale between 1.0 and 1.4 TeV for several formalisms and numbers of extra dimensions. PMID:11178033

  3. Elliptical instability in terrestrial planets and moons

    NASA Astrophysics Data System (ADS)

    Cebron, D.; Le Bars, M.; Moutou, C.; Le Gal, P.

    2012-03-01

    Context. The presence of celestial companions means that any planet may be subject to three kinds of harmonic mechanical forcing: tides, precession/nutation, and libration. These forcings can generate flows in internal fluid layers, such as fluid cores and subsurface oceans, whose dynamics then significantly differ from solid body rotation. In particular, tides in non-synchronized bodies and libration in synchronized ones are known to be capable of exciting the so-called elliptical instability, i.e. a generic instability corresponding to the destabilization of two-dimensional flows with elliptical streamlines, leading to three-dimensional turbulence. Aims: We aim here at confirming the relevance of such an elliptical instability in terrestrial bodies by determining its growth rate, as well as its consequences on energy dissipation, on magnetic field induction, and on heat flux fluctuations on planetary scales. Methods: Previous studies and theoretical results for the elliptical instability are re-evaluated and extended to cope with an astrophysical context. In particular, generic analytical expressions of the elliptical instability growth rate are obtained using a local WKB approach, simultaneously considering for the first time (i) a local temperature gradient due to an imposed temperature contrast across the considered layer or to the presence of a volumic heat source and (ii) an imposed magnetic field along the rotation axis, coming from an external source. Results: The theoretical results are applied to the telluric planets and moons of the solar system as well as to three Super-Earths: 55 CnC e, CoRoT-7b, and GJ 1214b. For the tide-driven elliptical instability in non-synchronized bodies, only the early Earth core is shown to be clearly unstable. For the libration-driven elliptical instability in synchronized bodies, the core of Io is shown to be stable, contrary to previously thoughts, whereas Europa, 55 CnC e, CoRoT-7b, and GJ 1214b cores can be unstable. The subsurface ocean of Europa is slightly unstable. However, these present states do not preclude more unstable situations in the past.

  4. On the Ways That Planetesimals Were Analogs to Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Elkins-Tanton, L. T.

    2014-12-01

    Terrestrial planets are now understood to accrete from smaller bodies - both planetesimals and planetary embryos - that are, at least in many cases, already internally differentiated into a metallic core and a silicate mantle. The final terrestrial planet retains few or no unmodified vestiges of the first bodies from which it formed; each planet is the result of multiple heating, melting, and differentiation events as it grew and also on the bodies from which it grew. Planetesimals and embryos, however, are imperfect miniature physical analogs to today's Earth. The small gravity fields produce different physical processes, as would the potentially higher temperatures, the dominance of internal radiogenic heating, and the possibility of far higher volatile fractions. The meteorite collection contains samples of undifferentiated primitive material from planetesimals along with both silicates and iron-nickel metal from differentiated planetesimals. Conspicuously lacking is olivine-dominated material similar to the Earth's mantle or resulting from magmatic fractionation. Perhaps our collection simply lacks these samples but they did originally exist. Perhaps, however, in the small gravity field of a planetesimal magmas cannot efficiently fractionate, and no olivine-dominated material can be produced; the mantles and crusts of planetesimals may have been significantly different than our Earth, Venus, and Mars examples. Even in the low-gravity environment, however, metal can segregate into a core, and this core can produce a magnetic dynamo. And because each planetary core is the result of combining many smaller, pre-differentiated cores from other bodies, each core (except the very first differentiation event) is a combination of many others that went through multiple melting, solidification, collision, and disruption events. Thus core materials and processes on planetesimals may have been higher-fidelity analogs to the cores of terrestrial planets than are their mantles and crusts.

  5. FORMATION OF THE TERRESTRIAL PLANETS FROM A NARROW ANNULUS

    SciTech Connect

    Hansen, Brad M. S.

    2009-09-20

    We show that the assembly of the solar system terrestrial planets can be successfully modeled with all of the mass initially confined to a narrow annulus between 0.7 and 1.0 AU. With this configuration, analogs of Mercury and Mars often form from the collisional evolution of material diffusing out of the annulus under the scattering of the forming Earth and Venus analogs. The final systems also possess eccentricities and inclinations that match the observations, without recourse to dynamical friction from remnant small body populations. Finally, the characteristic assembly timescale for Earth analogs is rapid in this model and consistent with cosmochemical models based on the {sup 182}Hf-{sup 182}W isotopes. The agreement between this model and the observations suggests that terrestrial planet systems may also be formed in 'planet traps', as has been proposed recently for the cores of giant planets in our solar system and others.

  6. Reduction and identification for hybrid dynamical models of terrestrial locomotion

    NASA Astrophysics Data System (ADS)

    Burden, Samuel A.; Sastry, S. Shankar

    2013-06-01

    The study of terrestrial locomotion has compelling applications ranging from design of legged robots to development of novel prosthetic devices. From a first-principles perspective, the dynamics of legged locomotion seem overwhelmingly complex as nonlinear rigid body dynamics couple to a granular substrate through viscoelastic limbs. However, a surfeit of empirical data demonstrates that animals use a small fraction of their available degrees-of-freedom during locomotion on regular terrain, suggesting that a reduced-order model can accurately describe the dynamical variation observed during steady-state locomotion. Exploiting this emergent phenomena has the potential to dramatically simplify design and control of micro-scale legged robots. We propose a paradigm for studying dynamic terrestrial locomotion using empirically-validated reduced{order models.

  7. 29 CFR 1620.20 - Pay differentials claimed to be based on extra duties.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... extra duties do not in fact exist; (d) The extra task consumes a minimal amount of time and is of... being compared) who do the extra task as their primary job are paid less than the members of the...

  8. 29 CFR 1620.20 - Pay differentials claimed to be based on extra duties.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... extra duties do not in fact exist; (d) The extra task consumes a minimal amount of time and is of... being compared) who do the extra task as their primary job are paid less than the members of the...

  9. Sustainability of Terrestrial Carbon Sinks

    NASA Astrophysics Data System (ADS)

    Field, C. B.

    2001-12-01

    The problem of predicting the future trajectory of terrestrial carbon sinks has five components. These are (1) the attribution of current sinks among causal mechanisms, (2) the intrinsic trajectory of the sink resulting from each mechanism, (3) the future trajectory of environmental conditions, (4) the sensitivity of sinks to future environmental conditions, and (5) the prospect for future sinks due to novel mechanisms. This analysis of sinks must be placed in the broader context of carbon balance, including not only sinks, but also sources. The attribution problem is central to the question of the future of carbon sinks because each of the potential mechanisms has different intrinsic dynamics, responds differently to environmental changes, and is influenced by a different set of human actions. Until recently, most analyses assumed that the past and future trajectory of terrestrial carbon sinks could be understood as a function of climate and atmospheric composition alone, without a major contribution of direct effects of human actions. Increasingly, it is clear that this perspective is too limited. In many settings, current sinks are probably dominated by the history of land management. Interactions among these major regulators may be as important as the single-factor effects. As emphasis on CO2 and climate as the sole or dominant explanation for terrestrial sinks has faded, a number of new potential mechanisms have emerged, including, (1) climate change, (2) CO2 fertilization, (3) nitrogen fertilization, (4) the regrowth of previously harvested forests, (5) the abandonment of agricultural land, (6) changes in agricultural management, (7) increasing woodiness of grassland and savanna vegetation, (8) fire suppression, (9) accumulation in landfalls, and (10) accumulation in durable products. None of these mechanisms produces an indefinite sink. For some mechanisms, the potential is influenced primarily by the interaction between ecosystem processes and the trajectory of climate and atmospheric change. For others, the historical pattern of human actions is the dominant influence. These two classes of regulators interact for all of the mechanisms.

  10. Topological effects in our brane world from extra dimensions

    SciTech Connect

    Dvali, G.; Kogan, Ian I.; Shifman, M.

    2000-11-15

    The theories in which our world presents a domain wall (brane) embedded in large extra dimensions predict new types of topological defects. These defects arise due to the fact that the brane on which we live spontaneously breaks isometries of the extra space giving mass to some graviphotons. In many cases the corresponding vacuum manifold has nontrivial homotopies -- this gives rise to topologically stable defects in four dimensions, such as cosmic strings and monopoles that carry gravimagnetic flux. The core structure of these defects is somewhat peculiar. Because of the fact that the translation invariance in the extra direction(s) is restored in their core, they act as ''windows'' to the extra dimensions. We also discuss the corresponding analogue of the Alice strings. Encircling such an object one would get transported onto a parallel brane.

  11. ExTrA: Exoplanets in transit and their atmospheres

    NASA Astrophysics Data System (ADS)

    Bonfils, X.; Almenara, J. M.; Jocou, L.; Wunsche, A.; Kern, P.; Delboulb, A.; Delfosse, X.; Feautrier, P.; Forveille, T.; Gluck, L.; Lafrasse, S.; Magnard, Y.; Maurel, D.; Moulin, T.; Murgas, F.; Rabou, P.; Rochat, S.; Roux, A.; Stadler, E.

    2015-09-01

    The ExTrA facility, located at La Silla observatory, will consist of a near-infrared multi-object spectrograph fed by three 60-cm telescopes. ExTrA will add the spectroscopic resolution to the traditional differential photometry method. This shall enable the fine correction of color-dependent systematics that would otherwise hinder ground-based observations. With both this novel method and an infrared-enabled efficiency, ExTrA aims to find transiting telluric planets orbiting in the habitable zone of bright nearby M dwarfs. It shall have the versatility to do so by running its own independent survey and also by concurrently following-up on the space candidates unveiled by K2 and TESS. The exoplanets detected by ExTrA will be amenable to atmospheric characterisation with VLTs, JWST, and ELTs and could give our first peek into an exo-life laboratory.

  12. Constraints on large extra dimensions from neutrino oscillation experiments

    NASA Astrophysics Data System (ADS)

    Davoudiasl, H.; Langacker, P.; Perelstein, M.

    2002-05-01

    The existence of bulk sterile neutrinos in theories with large extra dimensions can naturally explain small 4-dimensional Dirac masses for the active neutrinos. We study a model with 3 bulk neutrinos and derive various constraints on the size of the extra dimensions from neutrino oscillation experiments. Our analysis includes recent solar and atmospheric data from SNO and Super-Kamiokande, respectively, as well as various reactor and accelerator experiments. In addition, we comment on possible extensions of the model that could accommodate the LSND results, using natural parameters only. Our most conservative bound, obtained from the atmospheric data in the hierarchical mass scheme, constrains the largest extra dimension to have a radius R<0.82 ?m. Thus, in the context of the model studied here, future gravitational experiments are unlikely to observe the effects of extra dimensions.

  13. 7. LESLIE WICKMAN, EVA (EXTRA VEHICULAR ACTIVITIES) SPECIALIST, IN SPACE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. LESLIE WICKMAN, EVA (EXTRA VEHICULAR ACTIVITIES) SPECIALIST, IN SPACE SUIT AFTER TESTING IN NEUTRAL BUOYANCY TANK. AVERAGE COST OF SUIT IS $1,000,000. - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

  14. Families of Critically Ill Patients Need Extra Support, Too

    MedlinePLUS

    ... medlineplus/news/fullstory_156481.html Families of Critically Ill Patients Need Extra Support, Too Tips for coping ... center at Loyola University Health System in Maywood, Ill. Each year, roughly 2.1 million patients are ...

  15. Probing large extra dimensions with IceCube

    SciTech Connect

    Esmaili, Arman; Peres, O.L.G.; Tabrizi, Zahra E-mail: orlando@ifi.unicamp.br

    2014-12-01

    In models with Large Extra Dimensions the smallness of neutrino masses can be naturally explained by introducing gauge singlet fermions which propagate in the bulk. The Kaluza-Klein modes of these fermions appear as towers of sterile neutrino states on the brane. We study the phenomenological consequences of this picture for the high energy atmospheric neutrinos. For this purpose we construct a detailed equivalence between a model with large extra dimensions and a (3+n) scenario consisting of three active and n extra sterile neutrino states, which provides a clear intuitive understanding of Kaluza-Klein modes. Finally, we analyze the collected data of high energy atmospheric neutrinos by IceCube experiment and obtain bounds on the radius of extra dimensions.

  16. Adrenal and Extra-adrenal Myelolipomas - A Comparative Case Report

    PubMed Central

    Hakim, Arsany; Rozeik, Christoph

    2014-01-01

    Myelolipoma is an uncommon benign tumour composed of mature fat tissue and haematopoietic elements and is most commonly found in the adrenal gland. We report a case, which was discovered incidentally on chest X-ray, of a rare occurrence of multifocal extra-adrenal myelolipoma in the thoracic paravertebral region. This was further investigated with multi-detector computed tomography and magnetic resonance imaging. The presumed diagnosis, of extra-adrenal myelolipoma, was histologically confirmed via tissue sample obtained by computed tomography guided biopsy. We compare the adrenal and extra-adrenal entities from the perspective of published literature and also review the cases, published in Pubmed, of extra-adrenal myelolipomas in order to summarize the different locations of this lesion. PMID:24967008

  17. Solar terrestrial observatory. Final Report

    SciTech Connect

    Not Available

    1981-10-01

    Eight basic solar-terrestrial scientific objectives that benefit from the Shuttle/Platform approach and a program of measurements for each are discussed. The objectives are to understand: (1) solar variability, (2) wave-particle processes, (3) magnetosphere-ionosphere mass transport, (4) the global electric circuit, (5) upper atmospheric dynamics, (6) middle atmospheric chemistry and energetics, (7) lower atmospheric turbidity, and (8) planetary atmospheric waves. A two stage approach to a multidisciplinary payload is developed: an initial STO, that uses a single platform in a low-Earth orbit, and an advanced STO that uses two platforms in differing orbits.

  18. Groundwater and Terrestrial Water Storage

    NASA Technical Reports Server (NTRS)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2014-01-01

    Terrestrial water storage (TWS) comprises groundwater, soil moisture, surface water, snow,and ice. Groundwater typically varies more slowly than the other TWS components because itis not in direct contact with the atmosphere, but often it has a larger range of variability onmultiannual timescales (Rodell and Famiglietti, 2001; Alley et al., 2002). In situ groundwaterdata are only archived and made available by a few countries. However, monthly TWSvariations observed by the Gravity Recovery and Climate Experiment (GRACE; Tapley et al.,2004) satellite mission, which launched in 2002, are a reasonable proxy for unconfinedgroundwater at climatic scales.

  19. Effects of Type I Migration on Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    McNeil, D. S.; Duncan, M. J.; Levison, H. F.

    2004-11-01

    Planetary embryos embedded in a gas disk suffer a decay in semimajor axis -- type I migration -- due to the asymmetric torques produced by the interior and exterior wakes raised by the body (Goldreich and Tremaine 1980; Ward 1986). This presents a challenge for standard oligarchic approaches to forming the terrestrial planets (Kokubo and Ida 1998) as the timescale to grow the progenitor objects near 1 AU is longer than that for them to decay into the Sun. Using both semianalytic methods (based upon Thommes et al 2003) and large N-body integrations using a parallel implementation of the symplectic integrator SyMBA (Duncan, Levison, and Lee 1998) we investigate this problem by varying gas properties such as dissipation timescale in different models of the protoplanetary disk. We conclude that even for near-nominal migration efficiencies and dissipation timescales of 1 Myr it is possible to maintain sufficient mass in the terrestrial region to form Earth and Venus if the disk mass is substantially enhanced over the minimum mass model. The resulting configurations differ in several ways from the initial conditions used in previous simulations of the final stages of terrestrial accretion (e.g. Chambers 2001), chiefly in (1) larger interembryo spacings, (2) somewhat larger embryo masses, and (3) up to 1 Earth mass of material left in the form of planetesimals when the gas vanishes. The systems we produce are reasonably stable for 100 Myr and therefore require an external source to stir up the embryos sufficiently to produce final systems resembling the terrestrial planets. In an example following Kominami and Ida (2004), we consider the effects on the evolution of our configurations of the formation of Jupiter and Saturn. Recent results and plans for future work are discussed.

  20. [On mistakes in contemporary literatures of extra points in China].

    PubMed

    Huang, Long-Xiang; Huang, You-Min

    2013-06-01

    Contemporary literatures which are taken as the base of literature study of extra points are insufficient and lack of reliability. The foundation of study is very weak. Based on abundant firsthand materials, analyses are made on the major problems of confounded names and locations, unclear quotation and source of reference in the study of contemporary literatures of extra points. Meanwhile, methods and way of thinking for solving the above mentioned problems are discussed in this article as well. PMID:23967640

  1. Extra-Pair Mating and Evolution of Cooperative Neighbourhoods

    PubMed Central

    Eliassen, Sigrunn; Jrgensen, Christian

    2014-01-01

    A striking but unexplained pattern in biology is the promiscuous mating behaviour in socially monogamous species. Although females commonly solicit extra-pair copulations, the adaptive reason has remained elusive. We use evolutionary modelling of breeding ecology to show that females benefit because extra-pair paternity incentivizes males to shift focus from a single brood towards the entire neighbourhood, as they are likely to have offspring there. Male-male cooperation towards public goods and dear enemy effects of reduced territorial aggression evolve from selfish interests, and lead to safer and more productive neighbourhoods. The mechanism provides adaptive explanations for the common empirical observations that females engage in extra-pair copulations, that neighbours dominate as extra-pair sires, and that extra-pair mating correlates with predation mortality and breeding density. The models predict cooperative behaviours at breeding sites where males cooperate more towards public goods than females. Where maternity certainty makes females care for offspring at home, paternity uncertainty and a potential for offspring in several broods make males invest in communal benefits and public goods. The models further predict that benefits of extra-pair mating affect whole nests or neighbourhoods, and that cuckolding males are often cuckolded themselves. Derived from ecological mechanisms, these new perspectives point towards the evolution of sociality in birds, with relevance also for mammals and primates including humans. PMID:24987839

  2. The Laboratory for Terrestrial Physics

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Laboratory for Terrestrial Physics is dedicated to the advancement of knowledge in Earth and planetary science, by conducting innovative research using space technology. The Laboratory's mission and activities support the work and new initiatives at NASA's Goddard Space Flight Center (GSFC). The Laboratory's success contributes to the Earth Science Directorate as a national resource for studies of Earth from Space. The Laboratory is part of the Earth Science Directorate based at the GSFC in Greenbelt, MD. The Directorate itself is comprised of the Global Change Data Center (GCDC), the Space Data and Computing Division (SDCD), and four science Laboratories, including Laboratory for Terrestrial Physics, Laboratory for Atmospheres, and Laboratory for Hydrospheric Processes all in Greenbelt, MD. The fourth research organization, Goddard Institute for Space Studies (GISS), is in New York, NY. Relevant to NASA's Strategic Plan, the Laboratory ensures that all work undertaken and completed is within the vision of GSFC. The philosophy of the Laboratory is to balance the completion of near term goals, while building on the Laboratory's achievements as a foundation for the scientific challenges in the future.

  3. Cadaver decomposition in terrestrial ecosystems

    NASA Astrophysics Data System (ADS)

    Carter, David O.; Yellowlees, David; Tibbett, Mark

    2007-01-01

    A dead mammal (i.e. cadaver) is a high quality resource (narrow carbon:nitrogen ratio, high water content) that releases an intense, localised pulse of carbon and nutrients into the soil upon decomposition. Despite the fact that as much as 5,000 kg of cadaver can be introduced to a square kilometre of terrestrial ecosystem each year, cadaver decomposition remains a neglected microsere. Here we review the processes associated with the introduction of cadaver-derived carbon and nutrients into soil from forensic and ecological settings to show that cadaver decomposition can have a greater, albeit localised, effect on belowground ecology than plant and faecal resources. Cadaveric materials are rapidly introduced to belowground floral and faunal communities, which results in the formation of a highly concentrated island of fertility, or cadaver decomposition island (CDI). CDIs are associated with increased soil microbial biomass, microbial activity (C mineralisation) and nematode abundance. Each CDI is an ephemeral natural disturbance that, in addition to releasing energy and nutrients to the wider ecosystem, acts as a hub by receiving these materials in the form of dead insects, exuvia and puparia, faecal matter (from scavengers, grazers and predators) and feathers (from avian scavengers and predators). As such, CDIs contribute to landscape heterogeneity. Furthermore, CDIs are a specialised habitat for a number of flies, beetles and pioneer vegetation, which enhances biodiversity in terrestrial ecosystems.

  4. The Emergence of Terrestrial Hydrometeorology

    NASA Astrophysics Data System (ADS)

    Shuttleworth, W. J.

    2011-12-01

    In the Encyclopaedia of Atmospheric Sciences and Astrogeology Langbein (1967) defined hydroclimatology as "the study of the influence of climate upon the waters of the land", and hydrometeorology is study of short term processes and phenomena within this climatology. But this definition is now outdated because it implies too passive a role for land surface influences on the overlying atmosphere. Over the subsequent decades research has demonstrated that proper understanding of land surface hydrology requires investigations of the hydrometeorological processes that couple terrestrial surfaces and the atmosphere. These investigations include the development and calibration of land surface models; mesoscale field experiments, that considered heterogeneity in land surface cover and investigated their aggregate representation; studies of how coupling processes relate to the concept of potential evaporation, and how estimates of irrigated crop water requirement can be updated; application of remotely sensed data and the simplifying benefits of in-plant linkages between water vapor and carbon exchange mechanisms; and the potential benefits of now-feasible area-average soil moisture measurement. This lecture reviews such investigations in the area of terrestrial hydrometeorology with some emphasis on those that have involved the speaker's participation, and argues for the creation for a new branch of scientific education focused on the subject area that lies at the interface between hydrology and meteorology.

  5. Dietary characterization of terrestrial mammals

    PubMed Central

    Pineda-Munoz, Silvia; Alroy, John

    2014-01-01

    Understanding the feeding behaviour of the species that make up any ecosystem is essential for designing further research. Mammals have been studied intensively, but the criteria used for classifying their diets are far from being standardized. We built a database summarizing the dietary preferences of terrestrial mammals using published data regarding their stomach contents. We performed multivariate analyses in order to set up a standardized classification scheme.Ideally, food consumption percentages should be used instead of qualitative classifications. However, when highly detailed information is not available we propose classifying animals based on their main feeding resources. They should be classified as generalists when none of the feeding resources constitute over 50% of the diet. The term omnivore should be avoided because it does not communicate all the complexity inherent to food choice. Moreover, the so-called omnivore diets actually involve several distinctive adaptations. Our dataset shows that terrestrial mammals are generally highly specialized and that some degree of food mixing may even be required for most species. PMID:25009067

  6. Tectonic evolution of terrestrial planets

    NASA Technical Reports Server (NTRS)

    Head, J. W.; Solomon, S. C.

    1981-01-01

    The tectonic style of each terrestrial planet, referring to the thickness and division of its lithosphere, can be inferred from surface features and compared to models of planetary thermal history. Factors governing planetary tectonic evolution are planet diameter, chemistry, and external and internal heat sources, all of which determine how a planet generates and rids itself of heat. The earth is distinguished by its distinct, mobile plates, which are recycled into the mantle and show large-scale lateral movements, whereas the moon, Mars, and Mercury are single spherical shells, showing no evidence of destruction and renewal of the lithospheric plates over the latter 80% of their history. Their smaller volume to surface area results in a more rapid cooling, formation, and thickening of the lithosphere. Vertical tectonics, due to lithospheric loading, is controlled by the local thickness and rheology of the lithosphere. Further studies of Venus, which displays both the craterlike surface features of the one-plate planets, and the rifts and plateaus of earth, may indicate which factors are most important in controlling the tectonic evolution of terrestrial planets.

  7. Cadaver decomposition in terrestrial ecosystems.

    PubMed

    Carter, David O; Yellowlees, David; Tibbett, Mark

    2007-01-01

    A dead mammal (i.e. cadaver) is a high quality resource (narrow carbon:nitrogen ratio, high water content) that releases an intense, localised pulse of carbon and nutrients into the soil upon decomposition. Despite the fact that as much as 5,000 kg of cadaver can be introduced to a square kilometre of terrestrial ecosystem each year, cadaver decomposition remains a neglected microsere. Here we review the processes associated with the introduction of cadaver-derived carbon and nutrients into soil from forensic and ecological settings to show that cadaver decomposition can have a greater, albeit localised, effect on belowground ecology than plant and faecal resources. Cadaveric materials are rapidly introduced to belowground floral and faunal communities, which results in the formation of a highly concentrated island of fertility, or cadaver decomposition island (CDI). CDIs are associated with increased soil microbial biomass, microbial activity (C mineralisation) and nematode abundance. Each CDI is an ephemeral natural disturbance that, in addition to releasing energy and nutrients to the wider ecosystem, acts as a hub by receiving these materials in the form of dead insects, exuvia and puparia, faecal matter (from scavengers, grazers and predators) and feathers (from avian scavengers and predators). As such, CDIs contribute to landscape heterogeneity. Furthermore, CDIs are a specialised habitat for a number of flies, beetles and pioneer vegetation, which enhances biodiversity in terrestrial ecosystems. PMID:17091303

  8. The physics and chemistry of terrestrial planet and satellite accretion

    NASA Astrophysics Data System (ADS)

    Wasem, Christina A. Dwyer

    This dissertation examines the influence which a geophysical process (giant impacts) has on a geochemical marker (composition) during terrestrial planet formation. Simultaneously studying all planets maximizes the available constraints and permits examination of controls on the overall composition of the Earth. I also examine the Galilean satellite system to determine the universality of the terrestrial conclusions. The late stages of planetary accretion involve stochastic, large collisions. Impact-related erosion and fragmentation can have profound consequences for the rate and style of accretion and the bulk chemistries of terrestrial planets. However, the previous predominate assumption in computer models of accretion was that all collisions resulted in perfect merging despite the likelihood of these collisions producing a range of outcomes (e.g., hit-and-run, removal of material from target, or production of several post-collision bodies). In this work, I investigate the effects of late-stage accretion with multiple collision types and the consequences on the bulk (mantle/core) and isotopic (Hf--W) composition. My model is composed of two parts: (1) N-body accretion code tracks orbital and collisional evolution of the bodies and (2) geochemical post-processing evolves composition in light of impact-related mixing, partial equilibration and radioactive decay. For terrestrial planets, Part (1) is Chambers (2013, Icarus) and incorporates multiple collisional outcomes. For Galilean satellites, Part (1) is Ogihara & Ida (2012, Icarus) and assumes perfect merging for all collisions thus the model is not self-consistent (it likely overestimates compositional changes). For the terrestrial planets, the results are consistent with observed mantle/core ratios and tungsten isotopic anomalies. A moderate (approx. 0.4) core equilibration factor is preferred due to protracted accretion time. It is important to include multi-modal collisions when modeling planet formation if composition, timescales, or spatial distribution of mass are being investigated. I could not reproduce the observed ice fraction gradient of the Galilean satellites, even with an initial compositional gradient and vaporization of water ice. Some other physical process(es) are needed, perhaps tidally-driven volatile loss at Io and Europa. Extensive inward radial migration smooths out initial compositional gradients.

  9. Volatiles Delivery to the Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Marov, M. Ya.; Ipatov, S. I.

    2006-08-01

    Migration of small bodies and dust particles from the outer regions of the solar system is an important mechanism of the formation and evolution of atmospheres and hydrospheres of the terrestrial planets [1]. It is assumed that these bodies and particles could be responsible for the delivery of the original matter (mainly volatiles) and thus could give rise to the life origin. A fraction of dust particles migrated inward solar system is believed to be of interstellar origin embedded in presolar nebula and preserved for a long time at the fringe of the solar system. Our studies of volatiles delivery were based on results of numerical integration of the migration of small bodies and dust particles in the Solar System [2]. It was shown that the exogenous mechanism of heterogeneous accretion and the endogenous mechanism of the interior degassing may contribute to the formation of planetary atmospheres and hydrospheres at least comparably. If the total mass of planetesimals beyond Jupiter's orbit exceeded a hundred of Earth masses, then of the total mass of volatiles delivered to the Earth exceeded the amount of water in the Earth's oceans. The results of our studies of the migration of dust particles of various genesis lead to the conclusion that a portion of cometary and trans-Neptunian dust particles highly enriched by volatiles can be considerable among particles of other origin. Although it is difficult to obtain exact estimates of the dust influx to the Earth and neighboring planets, it was shown that, in comparison with small bodies, the dust contribution is 3-4 orders of magnitude smaller. However, dust particles could have been most efficient in the delivery of organic prebiogenic and, most likely, biogenic matter, because they are subjected to substantially weaker heating at the altitudes at which they enter the atmosphere and decelerate in it. This conclusion is confirmed by laboratory investigations into the probability of survival of bacteria and phages heated up to 200^o C and allows one to consider dust as a potential carrier of biogenic material from outer space. [1] Marov M. Ya. and Ipatov S.I., Solar System Research, 2005, 39, 374-380. [2] Ipatov S.I. and Mather J.C., Advances in Space Research, 2006, 37, 126-137.

  10. The evolution of terrestrial-type planets.

    PubMed

    Anderson, D L

    1969-07-01

    The present internal state of the earth and the age of various events such as core formation and continental formation can be used to place fairly strong constraints on the early history of the earth and, presumably, the other terrestrial planets. The present internal configuration of the earth shows that it is an extremely differentiated body, and the ages of surface rocks indicate that this differentiation took place early in the history of the earth. The gravitational energy associated with the formation of the earth and the thermal energy of core formation are the primary sources of energy for the melting and subsequent gravitational separation of the earth into a core, a crust, a chemically inhomogeneous mantle, and an atmosphere and hydrosphere. The larger the planet the more likely it is to be extensively differentiaed and outgassed. The earth probably accreted in 10(5) years or less. This causes the initial temperatures to be high and results in core formation to be essentially simultaneous with accretion. Mars can be accreted without differentiation and with minor outgassing. PMID:20072427

  11. Local anisotropy of muon flux - The basis of the method of muon diagnostics of extra-terrestrial space

    NASA Astrophysics Data System (ADS)

    Astapov, I. I.; Barbashina, N. S.; Dmitrieva, A. N.; Kokoulin, R. P.; Petrukhin, A. A.; Shutenko, V. V.; Yakovleva, E. I.; Yashin, I. I.

    2015-12-01

    A new method for the analysis of spatial and angular characteristics of the cosmic ray muon flux registered in the hodoscopic mode using a single setup - the muon hodoscope - is presented. Various parameters of the muon flux anisotropy and methods of calculation of these parameters are discussed. It is shown that the horizontal projection of the muon flux relative anisotropy vector which characterizes lateral (horizontal) displacement of the muon flux angular distribution is the sensitive parameter to a variety of nonstationary processes in the heliosphere. The experimental data on the variation of the muon flux anisotropy during the passage of various irregularities in the solar wind and interplanetary magnetic field in the Earth's vicinity are presented.

  12. Trace element and isotope geochemistry of Cretaceous-Tertiary boundary sediments: identification of extra-terrestrial and volcanic components

    NASA Technical Reports Server (NTRS)

    Margolis, S. V.; Doehne, E. F.

    1988-01-01

    Trace element and stable isotope analyses were performed on a series of sediment samples crossing the Cretaceous-Tertiary (K-T) boundary from critical sections at Aumaya and Sopelano, Spain. The aim is to possibly distinguish extraterrestrial vs. volcanic or authigenic concentration of platinum group and other elements in K-T boundary transitional sediments. These sediments also have been shown to contain evidence for step-wise extinction of several groups of marine invertebrates, associated with negative oxygen and carbon isotope excursions occurring during the last million years of the Cretaceous. These isotope excursions have been interpreted to indicate major changes in ocean thermal regime, circulation, and ecosystems that may be related to multiple events during latest Cretaceous time. Results to date on the petrographic and geochemical analyses of the Late Cretaceous and Early Paleocene sediments indicate that diagenesis has obviously affected the trace element geochemistry and stable isotope compositions at Zumaya. Mineralogical and geochemical analysis of K-T boundary sediments at Zumaya suggest that a substantial fraction of anomalous trace elements in the boundary marl are present in specific mineral phases. Platinum and nickel grains perhaps represent the first direct evidence of siderophile-rich minerals at the boundary. The presence of spinels and Ni-rich particles as inclusions in aluminosilicate spherules from Zumaya suggests an original, non-diagenetic origin for the spherules. Similar spherules from southern Spain (Caravaca), show a strong marine authigenic overprint. This research represents a new approach in trying to directly identify the sedimentary mineral components that are responsible for the trace element concentrations associated with the K-T boundary.

  13. Body Composition.

    ERIC Educational Resources Information Center

    Mayhew, Jerry L.

    1981-01-01

    Body composition refers to the types and amounts of tissues which make up the body. The most acceptable method for assessing body composition is underwater weighing. A subcutaneous skinfold provides a quantitative measurement of fat below the skin. The skinfold technique permits a valid estimate of the body's total fat content. (JN)

  14. Demographic mechanisms of inbreeding adjustment through extra-pair reproduction

    PubMed Central

    Reid, Jane M; Duthie, A Bradley; Wolak, Matthew E; Arcese, Peter; van de Pol, Martijn

    2015-01-01

    One hypothesis explaining extra-pair reproduction is that socially monogamous females mate with extra-pair males to adjust the coefficient of inbreeding (f) of extra-pair offspring (EPO) relative to that of within-pair offspring (WPO) they would produce with their socially paired male. Such adjustment of offspring f requires non-random extra-pair reproduction with respect to relatedness, which is in turn often assumed to require some mechanism of explicit pre-copulatory or post-copulatory kin discrimination. We propose three demographic processes that could potentially cause mean f to differ between individual females’ EPO and WPO given random extra-pair reproduction with available males without necessarily requiring explicit kin discrimination. Specifically, such a difference could arise if social pairings formed non-randomly with respect to relatedness or persisted non-randomly with respect to relatedness, or if the distribution of relatedness between females and their sets of potential mates changed during the period through which social pairings persisted. We used comprehensive pedigree and pairing data from free-living song sparrows (Melospiza melodia) to quantify these three processes and hence investigate how individual females could adjust mean offspring f through instantaneously random extra-pair reproduction. Female song sparrows tended to form social pairings with unrelated or distantly related males slightly less frequently than expected given random pairing within the defined set of available males. Furthermore, social pairings between more closely related mates tended to be more likely to persist across years than social pairings between less closely related mates. However, these effects were small and the mean relatedness between females and their sets of potential extra-pair males did not change substantially across the years through which social pairings persisted. Our framework and analyses illustrate how demographic and social structuring within populations might allow females to adjust mean f of offspring through random extra-pair reproduction without necessarily requiring explicit kin discrimination, implying that adjustment of offspring f might be an inevitable consequence of extra-pair reproduction. New theoretical and empirical studies are required to explore the general magnitude of such effects and quantify the degree to which they could facilitate or constrain long-term evolution of extra-pair reproduction. PMID:25645743

  15. Review of existing terrestrial bioaccumulation models and terrestrial bioaccumulation modeling needs for organic chemicals

    EPA Science Inventory

    Protocols for terrestrial bioaccumulation assessments are far less-developed than for aquatic systems. This manuscript reviews modeling approaches that can be used to assess the terrestrial bioaccumulation potential of commercial organic chemicals. Models exist for plant, inver...

  16. About Tagish Lake as a Potential Parent Body for Polar Micrometeorites; Clues from their Hydrogen Isotopic Compositions

    NASA Technical Reports Server (NTRS)

    Engrand, C.; Gounelle, M.; Zolensky, M. E.; Duprat, J.

    2003-01-01

    The origin of the Antarctic micrometeorites (AMMs) is still a matter of debate. Their closest meteoritic counterparts are the C2 chondrites, but the match is not perfect, and the parent body(ies) of the AMMs is(are) still to be identified. Tagish Lake is a new meteorite fall which bears similarity with CI1 and CM2 chondrites, but is distinct from both. Based on the mineralogy of phyllosilicates, Noguchi et al. proposed that the phyllosilicate-rich AMMs and the Tagish Lake meteorites could derive from similar asteroids. The hydrogen isotopic compositions of extra-terrestrial samples can be used to get some insight on their origin. The D/H ratios of AMMs and of Tagish Lake have been measured, but using different analytical techniques. They are therefore not directly comparable. We performed additional hydrogen isotopic analyses of fragments of Tagish Lake using the same experimental setup previously used for the measurement of the hydrogen isotopic composition of AMMs. In this work, we could also analyze separately both lithologies of Tagish Lake (carbonate-poor and -rich). The distributions of delta D values measured in the two lithologies of Tagish Lake are very similar, indicating that fluids with similar hydrogen isotopic compositions altered the meteorite on the parent body for the two lithologies. Yet, the hydrogen isotopic composition of Tagish Lake is different from that of AMMs, suggesting that they do not derive from the same parent body.

  17. Irreversible evolution of the terrestrial planets (geological and petrological data)

    NASA Astrophysics Data System (ADS)

    Sharkov, E.; Bogatikov, O.

    2008-09-01

    Abstract Comparative studying of tectonomagmatic evolution of the Earth and the Moon shows that cardinal irreversible change in character of tectonomagmatic processes occurred at middle stages of their evolution; very likely such changes took place on other terrestrial planets (Venus, Mars and Mercury). As a result, primordial crusts of the planets were in considerable degree replaced by secondary basaltic ones. The established succession of events on the Earth could be provided by a combination of two independent factors: (1) it was originally heterogeneous and 2) its downward heating was followed by the cooling of its outer shells. As a result the primary iron core material was long time remained untouched and was involved into global tectonomagmatic processes at ca. 2.4-2.3 Ga. We concluded about a similar scenario for the evolution of Moon and other terrestrial planets. Tectonomagmatic evolution of the terrestrial planets (Earth, Venus, Mars, Mercury and Moon) was studied. What did major stages of their irreversible evolution occur before they turned into "dead" stone balls? We discuss these problems on examples of the Earth and the Moon, which evolution studied the best. According to modern views, after accretion of these bodies, magma oceans of some hundreds km deep appeared on their surface. According to Jeffries [1], solidification of large molted bodies, because of the difference between adiabatic gradient in silicate melts (0.3oC/km) and gradient of their melting points (3oC/km), could be going only upwards, from the bottom to the surface. As a result a powerful crystallizing differentiation of the oceans' magmas occurred with accumulation of the most low-melting components to the surface. Due to different deep of the magma oceans on the Earth and the Moon, the primordial crusts on these bodies were rather different: sialic on the Earth and basic (anorthosite) on the Moon.

  18. Perpetual long libration of terrestrial planets in tidal resonances

    NASA Astrophysics Data System (ADS)

    Makarov, Valeri

    2015-11-01

    On the example of Mercury, I show that firm planets of terrestrial composition, locked in the 3:2 or higher spin-orbit resonances, undergo long-period perpetual libration in longitude without any influence of third bodies. This non-damped libration at the natural frequency is driven by a secular tidal torque, which is increasing with frequency within a narrow interval around the resonance. The spectrum of regular forced, eccentricity-driven, libration defines the conditions for the perpetual long libration. The possibility of validating the tidal theory from the observable amplitude of perpetual libration is discussed.

  19. Axial allometry in a neutrally buoyant environment: effects of the terrestrial-aquatic transition on vertebral scaling.

    PubMed

    Jones, K E; Pierce, S E

    2016-03-01

    Ecological diversification into new environments presents new mechanical challenges for locomotion. An extreme example of this is the transition from a terrestrial to an aquatic lifestyle. Here, we examine the implications of life in a neutrally buoyant environment on adaptations of the axial skeleton to evolutionary increases in body size. On land, mammals must use their thoracolumbar vertebral column for body support against gravity and thus exhibit increasing stabilization of the trunk as body size increases. Conversely, in water, the role of the axial skeleton in body support is reduced, and, in aquatic mammals, the vertebral column functions primarily in locomotion. Therefore, we hypothesize that the allometric stabilization associated with increasing body size in terrestrial mammals will be minimized in secondarily aquatic mammals. We test this by comparing the scaling exponent (slope) of vertebral measures from 57 terrestrial species (23 felids, 34 bovids) to 23 semi-aquatic species (pinnipeds), using phylogenetically corrected regressions. Terrestrial taxa meet predictions of allometric stabilization, with posterior vertebral column (lumbar region) shortening, increased vertebral height compared to width, and shorter, more disc-shaped centra. In contrast, pinniped vertebral proportions (e.g. length, width, height) scale with isometry, and in some cases, centra even become more spool-shaped with increasing size, suggesting increased flexibility. Our results demonstrate that evolution of a secondarily aquatic lifestyle has modified the mechanical constraints associated with evolutionary increases in body size, relative to terrestrial taxa. PMID:26679743

  20. Methane production in terrestrial arthropods

    SciTech Connect

    Hackstein, J.H.P.; Stumm, C.K. )

    1994-06-07

    The authors have screened more than 110 representatives of the different taxa of terrestrial arthropods for methane production in order to obtain additional information about the origins of biogenic methane. Methanogenic bacteria occur in the hindguts of nearly all tropical representatives of millipedes (Diplopoda), cockroaches (Blattaria), termites (Isoptera), and scarab beetles (Scarabaeidae), while such methanogens are absent from 66 other arthropod species investigated. Three types of symbiosis were found: in the first type, the arthropod's hindgut is colonized by free methanogenic bacteria; in the second type, methanogens are closely associated with chitinous structures formed by the host's hindgut; the third type is mediated by intestinal anaerobic protists with intracellular methanogens. Such symbiotic associations are likely to be a characteristic property of the particular taxon. Since these taxa represent many families with thousands of species, the world populations of methane-producing arthropods constitute an enormous biomass. The authors show that arthropod symbionts can contribute substantially to atmospheric methane.

  1. Terrestrial versus giant planet formation

    NASA Technical Reports Server (NTRS)

    Boss, Alan P.

    1988-01-01

    Given a solar nebular surrounding the early protosun, containing dust grains that have already undergone growth through collisions to about centimeter-size, the question of the formation of the terrestrial and giant planets is considered. In contrast to the usual approach of emphasizing how well a problem is understood, the uncertainties and areas where more work needs to be done will be accentuated. Also, the emphasis will be on the dynamics of planetary formation, because profound problems still exist in this area, and because it seems most logical to concentrate first on the dynamical questions involved with assembling the planets before putting too much effort into the detailed chemical and geological consequences of certain formation mechanisms.

  2. Methane production in terrestrial arthropods.

    PubMed Central

    Hackstein, J H; Stumm, C K

    1994-01-01

    We have screened more than 110 representatives of the different taxa of terrestrial arthropods for methane production in order to obtain additional information about the origins of biogenic methane. Methanogenic bacteria occur in the hindguts of nearly all tropical representatives of millipedes (Diplopoda), cockroaches (Blattaria), termites (Isoptera), and scarab beetles (Scarabaeidae), while such methanogens are absent from 66 other arthropod species investigated. Three types of symbiosis were found: in the first type, the arthropod's hindgut is colonized by free methanogenic bacteria; in the second type, methanogens are closely associated with chitinous structures formed by the host's hindgut; the third type is mediated by intestinal anaerobic protists with intracellular methanogens. Such symbiotic associations are likely to be a characteristic property of the particular taxon. Since these taxa represent many families with thousands of species, the world populations of methane-producing arthropods constitute an enormous biomass. We show that arthropod symbionts can contribute substantially to atmospheric methane. Images PMID:8202505

  3. Line following terrestrial insect biobots.

    PubMed

    Latif, Tahmid; Bozkurt, Alper

    2012-01-01

    The present day technology falls short in offering centimeter scale mobile robots that can function effectively under unknown and dynamic environmental conditions. Insects, on the other hand, exhibit an unmatched ability to navigate through a wide variety of environments and overcome perturbations by successfully maintaining control and stability. In this study, we use neural stimulation systems to wirelessly navigate cockroaches to follow lines to enable terrestrial insect biobots. We also propose a system-on-chip based ZigBee enabled wireless neurostimulation backpack system with on-board tissue-electrode bioelectrical coupling verification. Such a capability ensures an electrochemically safe stimulation and avoids irreversible damage to the interface which is often misinterpreted as habituation of the insect to the applied stimulation. PMID:23366056

  4. Phytopharmacological overview of Tribulus terrestris

    PubMed Central

    Chhatre, Saurabh; Nesari, Tanuja; Somani, Gauresh; Kanchan, Divya; Sathaye, Sadhana

    2014-01-01

    Tribulus terrestris (family Zygophyllaceae), commonly known as Gokshur or Gokharu or puncture vine, has been used for a long time in both the Indian and Chinese systems of medicine for treatment of various kinds of diseases. Its various parts contain a variety of chemical constituents which are medicinally important, such as flavonoids, flavonol glycosides, steroidal saponins, and alkaloids. It has diuretic, aphrodisiac, antiurolithic, immunomodulatory, antidiabetic, absorption enhancing, hypolipidemic, cardiotonic, central nervous system, hepatoprotective, anti-inflammatory, analgesic, antispasmodic, anticancer, antibacterial, anthelmintic, larvicidal, and anticariogenic activities. For the last few decades or so, extensive research work has been done to prove its biological activities and the pharmacology of its extracts. The aim of this review is to create a database for further investigations of the discovered phytochemical and pharmacological properties of this plant to promote research. This will help in confirmation of its traditional use along with its value-added utility, eventually leading to higher revenues from the plant. PMID:24600195

  5. Global Change and Terrestrial Ecosystems

    NASA Astrophysics Data System (ADS)

    Walker, Brian H.; Steffen, Will

    1996-11-01

    This major new book presents a collection of essays by leading authorities who address the current state of knowledge. The chapters bring together the early results of an international scientific research program designed to address what will happen to our ability to produce food and fiber, and what effects there will be on biological diversity under rapid environmental change. This book addresses how these changes to terrestrial ecosystems will feed back to further environmental change. International in scope, this state-of-the-art assessment will interest policymakers, students and scientists interested in global change, climate change and biodiversity. Special features include descriptions of a dynamic global vegetation model, developing generic crop models and a special section on the emerging discipline of global ecology.

  6. Solar Terrestrial Relations Observatory (STEREO)

    NASA Technical Reports Server (NTRS)

    Davila, Joseph M.; SaintCyr, O. C.

    2003-01-01

    The solar magnetic field is constantly generated beneath the surface of the Sun by the solar dynamo. To balance this flux generation, there is constant dissipation of magnetic flux at and above the solar surface. The largest phenomenon associated with this dissipation is the Coronal Mass Ejection (CME). The Solar and Heliospheric Observatory (SOHO) has provided remarkable views of the corona and CMEs, and served to highlight how these large interplanetary disturbances can have terrestrial consequences. STEREO is the next logical step to study the physics of CME origin, propagation, and terrestrial effects. Two spacecraft with identical instrument complements will be launched on a single launch vehicle in November 2007. One spacecraft will drift ahead and the second behind the Earth at a separation rate of 22 degrees per year. Observation from these two vantage points will for the first time allow the observation of the three-dimensional structure of CMEs and the coronal structures where they originate. Each STEREO spacecraft carries a complement of 10 instruments, which include (for the first time) an extensive set of both remote sensing and in-situ instruments. The remote sensing suite is capable of imaging CMEs from the solar surface out to beyond Earth's orbit (1 AU), and in-situ instruments are able to measure distribution functions for electrons, protons, and ions over a broad energy range, from the normal thermal solar wind plasma to the most energetic solar particles. It is anticipated that these studies will ultimately lead to an increased understanding of the CME process and provide unique observations of the flow of energy from the corona to the near-Earth environment. An international research program, the International Heliophysical Year (IHY) will provide a framework for interpreting STEREO data in the context of global processes in the Sun-Earth system.

  7. A Spherical Aerial Terrestrial Robot

    NASA Astrophysics Data System (ADS)

    Dudley, Christopher J.

    This thesis focuses on the design of a novel, ultra-lightweight spherical aerial terrestrial robot (ATR). The ATR has the ability to fly through the air or roll on the ground, for applications that include search and rescue, mapping, surveillance, environmental sensing, and entertainment. The design centers around a micro-quadcopter encased in a lightweight spherical exoskeleton that can rotate about the quadcopter. The spherical exoskeleton offers agile ground locomotion while maintaining characteristics of a basic aerial robot in flying mode. A model of the system dynamics for both modes of locomotion is presented and utilized in simulations to generate potential trajectories for aerial and terrestrial locomotion. Details of the quadcopter and exoskeleton design and fabrication are discussed, including the robot's turning characteristic over ground and the spring-steel exoskeleton with carbon fiber axle. The capabilities of the ATR are experimentally tested and are in good agreement with model-simulated performance. An energy analysis is presented to validate the overall efficiency of the robot in both modes of locomotion. Experimentally-supported estimates show that the ATR can roll along the ground for over 12 minutes and cover the distance of 1.7 km, or it can fly for 4.82 minutes and travel 469 m, on a single 350 mAh battery. Compared to a traditional flying-only robot, the ATR traveling over the same distance in rolling mode is 2.63-times more efficient, and in flying mode the system is only 39 percent less efficient. Experimental results also demonstrate the ATR's transition from rolling to flying mode.

  8. Peatland geoengineering: an alternative approach to terrestrial carbon sequestration.

    PubMed

    Freeman, Christopher; Fenner, Nathalie; Shirsat, Anil H

    2012-09-13

    Terrestrial and oceanic ecosystems contribute almost equally to the sequestration of ca 50 per cent of anthropogenic CO(2) emissions, and already play a role in minimizing our impact on Earth's climate. On land, the majority of the sequestered carbon enters soil carbon stores. Almost one-third of that soil carbon can be found in peatlands, an area covering just 2-3% of the Earth's landmass. Peatlands are thus well established as powerful agents of carbon capture and storage; the preservation of archaeological artefacts, such as ancient bog bodies, further attest to their exceptional preservative properties. Peatlands have higher carbon storage densities per unit ecosystem area than either the oceans or dry terrestrial systems. However, despite attempts over a number of years at enhancing carbon capture in the oceans or in land-based afforestation schemes, no attempt has yet been made to optimize peatland carbon storage capacity or even to harness peatlands to store externally captured carbon. Recent studies suggest that peatland carbon sequestration is due to the inhibitory effects of phenolic compounds that create an 'enzymic latch' on decomposition. Here, we propose to harness that mechanism in a series of peatland geoengineering strategies whereby molecular, biogeochemical, agronomical and afforestation approaches increase carbon capture and long-term sequestration in peat-forming terrestrial ecosystems. PMID:22869805

  9. Extra area effects of cloud seeding - An updated assessment

    NASA Astrophysics Data System (ADS)

    DeFelice, T. P.; Golden, J.; Griffith, D.; Woodley, W.; Rosenfeld, D.; Breed, D.; Solak, M.; Boe, B.

    2014-01-01

    This paper examines the commonly-held hypothesis that cloud seeding reduces precipitation in regions adjacent to seeding target areas, sometimes referred to as downwind but more correctly referred to as extra area effects (the robbing Peter to pay Paul hypothesis). The overall concept in the potential creation of extra area effects from seeding is illustrated with respect to the hydrologic cycle, which includes both dynamical and microphysical processes. For the first time, results were synthesized from five operational and research weather modification experiments, including winter orographic snowpack enhancement and summer experiments to enhance rainfall. One of the most surprising aspects of these results is that extra area seeding effects on precipitation appear to be uniformly positive (5-15% increases, perhaps greater for some convective systems) for both winter and summer seeding projects examined in this paper. The spatial extent of the positive extra area seeding effects may extend to a couple hundred kilometers for winter orographic seeding projects and summer convective seeding projects (such as North Dakota, Texas, Thailand). Both microphysical and dynamical effects of seeding appear to be contributors to these extra area effects. Future work needs to incorporate larger data sets from some of the larger more sustained projects with advanced cloud models and tracer experiments.

  10. Aerospace Power Technology for Potential Terrestrial Applications

    NASA Technical Reports Server (NTRS)

    Lyons, Valerie J.

    2012-01-01

    Aerospace technology that is being developed for space and aeronautical applications has great potential for providing technical advances for terrestrial power systems. Some recent accomplishments arising from activities being pursued at the National Aeronautics and Space Administration (NASA) Centers is described in this paper. Possible terrestrial applications of the new aerospace technology are also discussed.

  11. The influence of load carrying on the energetics and kinematics of terrestrial locomotion in a diving bird.

    PubMed

    Tickle, Peter G; Lean, Samantha C; Rose, Kayleigh A R; Wadugodapitiya, Avanti P; Codd, Jonathan R

    2013-01-01

    The application of artificial loads to mammals and birds has been used to provide insight into the mechanics and energetic cost of terrestrial locomotion. However, only two species of bird have previously been used in loading experiments, the cursorial guinea fowl (Numida meleagris) and the locomotor-generalist barnacle goose (Branta leucopsis). Here, using respirometry and treadmill locomotion, we investigate the energetic cost of carrying trunk loads in a diving bird, the tufted duck (Aythya fuligula). Attachment of back loads equivalent to 10% and 20% of body mass increased the metabolic rate during locomotion (7.94% and 15.92%, respectively) while sternal loads of 5% and 10% had a greater proportional effect than the back loads (metabolic rate increased by 7.19% and 13.99%, respectively). No effect on locomotor kinematics was detected during any load carrying experiments. These results concur with previous reports of load carrying economy in birds, in that there is a less than proportional relationship between increasing load and metabolic rate (found previously in guinea fowl), while application of sternal loads causes an approximate doubling of metabolic rate compared to back loads (reported in an earlier study of barnacle geese). The increase in cost when carrying sternal loads may result from having to move this extra mass dorso-ventrally during respiration. Disparity in load carrying economy between species may arise from anatomical and physiological adaptations to different forms of locomotion, such as the varying uncinate process morphology and hindlimb tendon development in goose, guinea fowl and duck. PMID:24244861

  12. The influence of load carrying on the energetics and kinematics of terrestrial locomotion in a diving bird

    PubMed Central

    Tickle, Peter G.; Lean, Samantha C.; Rose, Kayleigh A. R.; Wadugodapitiya, Avanti P.; Codd, Jonathan R.

    2013-01-01

    Summary The application of artificial loads to mammals and birds has been used to provide insight into the mechanics and energetic cost of terrestrial locomotion. However, only two species of bird have previously been used in loading experiments, the cursorial guinea fowl (Numida meleagris) and the locomotor-generalist barnacle goose (Branta leucopsis). Here, using respirometry and treadmill locomotion, we investigate the energetic cost of carrying trunk loads in a diving bird, the tufted duck (Aythya fuligula). Attachment of back loads equivalent to 10% and 20% of body mass increased the metabolic rate during locomotion (7.94% and 15.92%, respectively) while sternal loads of 5% and 10% had a greater proportional effect than the back loads (metabolic rate increased by 7.19% and 13.99%, respectively). No effect on locomotor kinematics was detected during any load carrying experiments. These results concur with previous reports of load carrying economy in birds, in that there is a less than proportional relationship between increasing load and metabolic rate (found previously in guinea fowl), while application of sternal loads causes an approximate doubling of metabolic rate compared to back loads (reported in an earlier study of barnacle geese). The increase in cost when carrying sternal loads may result from having to move this extra mass dorso-ventrally during respiration. Disparity in load carrying economy between species may arise from anatomical and physiological adaptations to different forms of locomotion, such as the varying uncinate process morphology and hindlimb tendon development in goose, guinea fowl and duck. PMID:24244861

  13. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size

    PubMed Central

    Kubo, Tai; Kubo, Mugino O.

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope’s rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna. PMID:26790003

  14. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size.

    PubMed

    Kubo, Tai; Kubo, Mugino O

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope's rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna. PMID:26790003

  15. Terrestrial Ages of Antarctic Meteorites- Update 1999

    NASA Technical Reports Server (NTRS)

    Nishiizumi, Kunihiko; Welten, K. C.; Caffee, Marc W.

    1999-01-01

    We are continuing our ongoing study of cosmogenic nuclides in Antarctic meteorites. In addition to the studies of exposure histories of meteorites, we study terrestrial ages and pairing of Antarctic meteorites and desert meteorites. Terrestrial ages of Antarctic meteorites provide information on meteorite accumulation mechanisms, mean weathering lifetimes, and influx rates. The determination of Cl-36(half-life=3.01 x 10(exp 5) y) terrestrial ages is one of our long-term on-going projects, however, in many instances neither Cl-36 or C-14 (5,730 y) yields an accurate terrestrial age. Using Ca-14 (1.04 x 10(exp 5) y) for terrestrial age determinations solves this problem by filling the c,ap in half-life between 14-C and Cl-36 ages. We are now applying the new Ca-41- Cl-36 terrestrial age method as well as the Cl-36-Be-10 method to Antarctic meteorites. Our measurements and C-14 terrestrial age determinations by the University of Arizona group are always complementary. We have measured Cl-36 in over 270 Antarctic meteorites since our previous compilation of terrestrial ages. Since a large number of meteorites have been recovered from many different icefields in Antarctica, we continue to survey the trends of terrestrial ages for different icefields. We have also measured detailed terrestrial ages vs. sample locations for Allan Hills, Elephant Moraine, and Lewis Cliff Icefields, where meteorites have been found with very long ages. The updated histograms of terrestrial ages of meteorites from the Allan Hills Main Icefield and Lewis Cliff Icefield are shown. These figures include C-14 ages obtained by the University of Arizona group. Pairs of meteorites are shown as one object for which the age is the average of all members of the same fall. The width of the bars represents 70,000 years, which was a typical uncertainty for Cl-36 ages. We reduced the uncertainty of terrestrial age determinations to approx. 40,000 years by using pairs of nuclides such as Ca-41-Cl-36 or Cl-36-Be-10. Meteorites found at the Allan Hills Icefields are much older than any other meteorites. The terrestrial ages cover a wide range and are as old as 2 My. Many of the Lewis Cliff meteorites are as old as the Allan Hills meteorites. So far, no clear correlation has been found between the terrestrial ages and the locations of the Lewis Cliff meteorites.

  16. Insignificant solar-terrestrial triggering of earthquakes

    USGS Publications Warehouse

    Love, Jeffrey J.; Thomas, Jeremy N.

    2013-01-01

    We examine the claim that solar-terrestrial interaction, as measured by sunspots, solar wind velocity, and geomagnetic activity, might play a role in triggering earthquakes. We count the number of earthquakes having magnitudes that exceed chosen thresholds in calendar years, months, and days, and we order these counts by the corresponding rank of annual, monthly, and daily averages of the solar-terrestrial variables. We measure the statistical significance of the difference between the earthquake-number distributions below and above the median of the solar-terrestrial averages by χ2 and Student's t tests. Across a range of earthquake magnitude thresholds, we find no consistent and statistically significant distributional differences. We also introduce time lags between the solar-terrestrial variables and the number of earthquakes, but again no statistically significant distributional difference is found. We cannot reject the null hypothesis of no solar-terrestrial triggering of earthquakes.

  17. Various approaches for vegetation filtering of terrestrial laser scans

    NASA Astrophysics Data System (ADS)

    Derron, M.-H.; Metzger, R.; Carrea, D.; Jaboyedoff, M.

    2012-04-01

    Rock cliffs analysis from terrestrial Lidar data requires frequently to merge multiple scans or to compare successive scans to detect cm changes or displacements. This processing step is known by the name of alignment. The presence of vegetation in between the sensor and the rock face may strongly impair the accuracy of alignment. It is then recommended to remove the points backscattered by the vegetation from the original point cloud before to proceed to the alignment. This procedure, also known as scan cleaning, can be very tedious and time consuming (and may stupidly increase the overall processing cost). We propose here to compare preliminary semi-automatic methods to remove vegetation points in terrestrial Lidar dataset. Two types of methods were tested: 1) spatial methods based on the geometrical arrangement of points in the lidar point cloud, 2) spectral methods using information collected by an extra sensor coupled to the Lidar. For the spatial methods, vegetation and non-vegetation points are classified through a curvature index. Points on vegetation show a high curvature index, as the points captured by foliage do not show a clear structure. Curvature is computed by means of eigen values analysis of the local covariance matrix. Segmentation of the dataset based on Gaussian Mixture Modeling of eigenvectors distribution is also investigated. For the spectral methods, various camera were tested. A mixed visible-near infrared (600-900 nm) camera with a three bands sensor appeared to be the most efficient, chlorophyll reflectivity having a very specific signature in this range of wavelength. Moreover a standard SLR camera can be quite easily transformed for this purpose. As the type of vegetation and/or the light condition may vary a lot between datasets, semi-automatic methods (with user defined thresholds) appears to be the most efficient. Further works will include the coupling of both spatial and spectral information.

  18. The Role of Extra-Credit Assignments in the Teaching of World Languages

    ERIC Educational Resources Information Center

    Alley, David

    2011-01-01

    The granting of extra credit is a hotly debated topic in all fields of education. Teachers are reluctant to offer extra credit for fear of inflating grades, but students are persistent in their demands for extra-credit points to which they have become accustomed. This article considers extra-credit assignments in the teaching of world languages.…

  19. The Role of Extra-Credit Assignments in the Teaching of World Languages

    ERIC Educational Resources Information Center

    Alley, David

    2011-01-01

    The granting of extra credit is a hotly debated topic in all fields of education. Teachers are reluctant to offer extra credit for fear of inflating grades, but students are persistent in their demands for extra-credit points to which they have become accustomed. This article considers extra-credit assignments in the teaching of world languages.

  20. 29 CFR 1620.20 - Pay differentials claimed to be based on extra duties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Pay differentials claimed to be based on extra duties. 1620... COMMISSION THE EQUAL PAY ACT 1620.20 Pay differentials claimed to be based on extra duties. Additional... extra duties do not in fact exist; (d) The extra task consumes a minimal amount of time and is...

  1. 29 CFR 1620.20 - Pay differentials claimed to be based on extra duties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Pay differentials claimed to be based on extra duties. 1620... COMMISSION THE EQUAL PAY ACT 1620.20 Pay differentials claimed to be based on extra duties. Additional... extra duties do not in fact exist; (d) The extra task consumes a minimal amount of time and is...

  2. 29 CFR 1620.20 - Pay differentials claimed to be based on extra duties.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 4 2013-07-01 2013-07-01 false Pay differentials claimed to be based on extra duties. 1620... COMMISSION THE EQUAL PAY ACT 1620.20 Pay differentials claimed to be based on extra duties. Additional... extra duties do not in fact exist; (d) The extra task consumes a minimal amount of time and is...

  3. Body Basics

    MedlinePLUS

    ... more about how the body works, what basic human anatomy is, and what happens when parts of the body don't function properly. Blood Bones, Muscles, and Joints Brain and Nervous System Digestive System ...

  4. Body Measurement.

    ERIC Educational Resources Information Center

    Neufeld, K. Allen

    1989-01-01

    Described are activities for measuring the human body. The activities include measurements and calculations, calculating volume and density, problems related to body measurement, and using a nomogram. Several charts, illustrations, and a nomogram are provided. (YP)

  5. Simple Non-Coriolis Treatments for Explaining Terrestrial East-West Deflections

    ERIC Educational Resources Information Center

    Wild, John F.

    1973-01-01

    Presents two simple methods of calculating the respective terrestrial westward and eastward displacements of a vertically projected and a perpendicularly dropped body which give due emphasis to physical principles, including Kepler's law, conservation of angular momentum, and nonrotating coordinate system with origin at the earth's center. (CC)

  6. Internal Representation and Memory Formation of Odor Preference Based on Oscillatory Activities in a Terrestrial Slug

    ERIC Educational Resources Information Center

    Sekiguchi, Tatsuhiko; Furudate, Hiroyuki; Kimura, Tetsuya

    2010-01-01

    The terrestrial slug "Limax" exhibits a highly developed ability to learn odors with a small nervous system. When a fluorescent dye, Lucifer Yellow (LY), is injected into the slug's body cavity after odor-taste associative conditioning, a group of neurons in the procerebral (PC) lobe, an olfactory center of the slug, is labeled by LY. We examined

  7. Internal Representation and Memory Formation of Odor Preference Based on Oscillatory Activities in a Terrestrial Slug

    ERIC Educational Resources Information Center

    Sekiguchi, Tatsuhiko; Furudate, Hiroyuki; Kimura, Tetsuya

    2010-01-01

    The terrestrial slug "Limax" exhibits a highly developed ability to learn odors with a small nervous system. When a fluorescent dye, Lucifer Yellow (LY), is injected into the slug's body cavity after odor-taste associative conditioning, a group of neurons in the procerebral (PC) lobe, an olfactory center of the slug, is labeled by LY. We examined…

  8. On the extra force in brane world scenario

    NASA Astrophysics Data System (ADS)

    Bejancu, Aurel; Farran, Hani Reda

    2014-09-01

    In the study of the dynamics in a 5D bulk from brane world scenario, an extra force with abnormal properties was detected (cf. [D. Youm, Extra force in brane worlds, Phys. Rev. D62 (2000) 084002; D. Youm, Null geodesics in brane world universe, Mod. Phys. Lett. A16 (2001) 2371; L. F. Zhang and Y. Z. Zhang, Null geodesics in brane world scenarios, Commun. Theor. Phys. (Beijing)41 (2004) 48]). In this paper, by using the Riemannian horizontal connection introduced in [A. Bejancu, A new point of view on general Kaluza-Klein theories, Progr. Theor. Phys.128 (2012) 541], we give a new definition for the extra force in a 5D bulk, and show that it does not contradict the 4D physics. In particular, we show that this force appears very rarely along geodesics in a warped 5D bulk.

  9. Confirmation and Distribution of Tetrodotoxin for the First Time in Terrestrial Invertebrates: Two Terrestrial Flatworm Species (Bipalium adventitium and Bipalium kewense)

    PubMed Central

    Stokes, Amber N.; Ducey, Peter K.; Neuman-Lee, Lorin; Hanifin, Charles T.; French, Susannah S.; Pfrender, Michael E.; Brodie, Edmund D.; Brodie Jr, Edmund D.

    2014-01-01

    The potent neurotoxin tetrodotoxin (TTX) is known from a diverse array of taxa, but is unknown in terrestrial invertebrates. Tetrodotoxin is a low molecular weight compound that acts by blocking voltage-gated sodium channels, inducing paralysis. However, the origins and ecological functions of TTX in most taxa remain mysterious. Here, we show that TTX is present in two species of terrestrial flatworm (Bipalium adventitium and Bipalium kewense) using a competitive inhibition enzymatic immunoassay to quantify the toxin and high phase liquid chromatography to confirm the presence. We also investigated the distribution of TTX throughout the bodies of the flatworms and provide evidence suggesting that TTX is used during predation to subdue large prey items. We also show that the egg capsules of B. adventitium have TTX, indicating a further role in defense. These data suggest a potential route for TTX bioaccumulation in terrestrial systems. PMID:24963791

  10. Universal Extra Dimension models with right-handed neutrinos

    NASA Astrophysics Data System (ADS)

    Matsumoto, Shigeki; Sato, Joe; Senami, Masato; Yamanaka, Masato

    2008-04-01

    Relic abundance of dark matter is investigated in the framework of universal extra dimension (UED) models with right-handed neutrinos. These models are free from the KK graviton problem in the minimal UED model. The first KK particle of the right-handed neutrino is a dark matter candidate in this framework. When ordinary neutrino masses are large enough such as the degenerate mass spectrum case, the dark matter relic abundance can increase significantly. The scale of the extra dimension consistent with cosmological observations can be 500 GeV in the minimal setup of UED models with right-handed neutrinos.

  11. FAST TRACK COMMUNICATION: A gravitational wave window on extra dimensions

    NASA Astrophysics Data System (ADS)

    Clarkson, Chris; Seahra, Sanjeev S.

    2007-05-01

    We report on the possibility of detecting a submillimetre-sized extra dimension by observing gravitational waves (GWs) emitted by point-like objects orbiting a braneworld black hole. Matter in the 'visible' universe can generate a discrete spectrum of high frequency GWs with amplitudes moderately weaker than the predictions of general relativity, while GW signals generated by matter on a 'shadow' brane hidden in the bulk are potentially strong enough to be detected using current technology. We know of no other astrophysical phenomena that produce GWs with a similar spectrum, which stresses the need to develop detectors capable of measuring this high-frequency signature of large extra dimensions.

  12. Shape versus volume: making large flat extra dimensions invisible.

    PubMed

    Dienes, Keith R

    2002-01-01

    We show that the shape moduli associated with large extra dimensions can have a dramatic effect on the corresponding Kaluza-Klein spectra. Specifically, shape moduli can change the mass gap, induce level crossings, and even interpolate between theories with different numbers of compactified dimensions. We also show that in certain cases it is possible to maintain the ratio between the higher-dimensional and four-dimensional Planck scales while simultaneously increasing the Kaluza-Klein graviton mass gap by an arbitrarily large factor. These observations can therefore be used to alleviate many of the experimental bounds on theories with large extra spacetime dimensions. PMID:11800932

  13. Minimum length, extra dimensions, modified gravity and black hole remnants

    SciTech Connect

    Maziashvili, Michael

    2013-03-01

    We construct a Hilbert space representation of minimum-length deformed uncertainty relation in presence of extra dimensions. Following this construction, we study corrections to the gravitational potential (back reaction on gravity) with the use of correspondingly modified propagator in presence of two (spatial) extra dimensions. Interestingly enough, for r?0 the gravitational force approaches zero and the horizon for modified Schwarzschild-Tangherlini space-time disappears when the mass approaches quantum-gravity energy scale. This result points out to the existence of zero-temperature black hole remnants in ADD brane-world model.

  14. Minimum length, extra dimensions, modified gravity and black hole remnants

    NASA Astrophysics Data System (ADS)

    Maziashvili, Michael

    2013-03-01

    We construct a Hilbert space representation of minimum-length deformed uncertainty relation in presence of extra dimensions. Following this construction, we study corrections to the gravitational potential (back reaction on gravity) with the use of correspondingly modified propagator in presence of two (spatial) extra dimensions. Interestingly enough, for r→0 the gravitational force approaches zero and the horizon for modified Schwarzschild-Tangherlini space-time disappears when the mass approaches quantum-gravity energy scale. This result points out to the existence of zero-temperature black hole remnants in ADD brane-world model.

  15. What does SN1987A say about extra dimensions?

    NASA Astrophysics Data System (ADS)

    Veerahanumak, Satheeshkumar

    2010-02-01

    There has been a tremendous progress in the last decade in our efforts to confront the String-inspired ideas with experiments or observations. There are two approaches to this problem. One is to use the LHC data and other is to use astronomical data. Among the latter, using SN1987A data for placing the constraints on the models of extra dimensions is very popular. In this poster, we consider all the possible energy loss mechanisms of SN1987A and study the constraints they place on the number and size of extra dimensions and the higher dimensional Planck scale in the ADD scenario. )

  16. Can polar bears use terrestrial foods to offset lost ice-based hunting opportunities?

    USGS Publications Warehouse

    Rode, Karyn D.; Robbins, Charles T.; Nelson, Lynne; Amstrup, Steven C.

    2015-01-01

    Increased land use by polar bears (Ursus maritimus) due to climate-change-induced reduction of their sea-ice habitat illustrates the impact of climate change on species distributions and the difficulty of conserving a large, highly specialized carnivore in the face of this global threat. Some authors have suggested that terrestrial food consumption by polar bears will help them withstand sea-ice loss as they are forced to spend increasing amounts of time on land. Here, we evaluate the nutritional needs of polar bears as well as the physiological and environmental constraints that shape their use of terrestrial ecosystems. Only small numbers of polar bears have been documented consuming terrestrial foods even in modest quantities. Over much of the polar bear's range, limited terrestrial food availability supports only low densities of much smaller, resident brown bears (Ursus arctos), which use low-quality resources more efficiently and may compete with polar bears in these areas. Where consumption of terrestrial foods has been documented, polar bear body condition and survival rates have declined even as land use has increased. Thus far, observed consumption of terrestrial food by polar bears has been insufficient to offset lost ice-based hunting opportunities but can have ecological consequences for other species. Warming-induced loss of sea ice remains the primary threat faced by polar bears.

  17. Pulmonary compliance and lung volume are related to terrestriality in anuran amphibians.

    PubMed

    Withers, Philip C; Hedrick, Michael S; Drewes, Robert C; Hillman, Stanley S

    2014-01-01

    Dehydration tolerance of anuran amphibians is directly related to their ability to mobilize lymphatic reserves, with more terrestrial species having more effective lymph mobilization dependent on specialized skeletal muscles acting directly on the lymph sacs and via pulmonary ventilation. Consequently, we tested the hypothesis that pulmonary compliance, lung volume, and femoral lymphatic sac volume were related to terrestriality-and, hence, lymph mobilization-for 18 species of aquatic, semiaquatic, or terrestrial anuran amphibians. Lung compliance and volume were significantly related to body mass, but there was no significant phylogenetic pattern. There were significant habitat-related patterns for mass-corrected and phylogenetically corrected residuals for these pulmonary variables. Femoral lymph volume was significantly related to body mass, with no significant phylogenetic pattern, and there was only a weak correlation for habitat with mass-corrected and phylogenetically corrected residuals. These results suggest that pulmonary volume and compliance are strongly related to terrestriality in anuran amphibians and are under significant selection pressure to enhance lymph mobilization, but lymph sac volume does not appear to have a major role in adaptation to terrestriality. PMID:24769702

  18. Integrated Estimates of Global Terrestrial Carbon Sequestration

    SciTech Connect

    Thomson, Allison M.; Izaurralde, R Cesar; Smith, Steven J.; Clarke, Leon E.

    2008-02-01

    Assessing the contribution of terrestrial carbon sequestration to international climate change mitigation requires integration across scientific and disciplinary boundaries. As part of a scenario analysis for the US Climate Change Technology Program, measurements and geographic data were used to develop terrestrial carbon sequestration estimates for agricultural soil carbon, reforestation and pasture management. These estimates were then applied in the MiniCAM integrated assessment model to evaluate mitigation strategies within policy and technology scenarios aimed at achieving atmospheric CO2 stabilization by 2100. Adoption of terrestrial sequestration practices is based on competition for land and economic markets for carbon. Terrestrial sequestration reach a peak combined rate of 0.5 to 0.7 Gt carbon yr-1 in mid-century with contributions from agricultural soil (0.21 Gt carbon yr-1), reforestation (0.31 Gt carbon yr-1) and pasture (0.15 Gt carbon yr-1). Sequestration rates vary over time period and with different technology and policy scenarios. The combined contribution of terrestrial sequestration over the next century ranges from 31 to 41 GtC. The contribution of terrestrial sequestration to mitigation is highest early in the century, reaching up to 20% of total carbon mitigation. This analysis provides insight into the behavior of terrestrial carbon mitigation options in the presence and absence of climate change mitigation policies.

  19. The impact of large terrestrial carnivores on Pleistocene ecosystems

    PubMed Central

    Van Valkenburgh, Blaire; Ripple, William J.; Meloro, Carlo; Roth, V. Louise

    2016-01-01

    Large mammalian terrestrial herbivores, such as elephants, have dramatic effects on the ecosystems they inhabit and at high population densities their environmental impacts can be devastating. Pleistocene terrestrial ecosystems included a much greater diversity of megaherbivores (e.g., mammoths, mastodons, giant ground sloths) and thus a greater potential for widespread habitat degradation if population sizes were not limited. Nevertheless, based on modern observations, it is generally believed that populations of megaherbivores (>800 kg) are largely immune to the effects of predation and this perception has been extended into the Pleistocene. However, as shown here, the species richness of big carnivores was greater in the Pleistocene and many of them were significantly larger than their modern counterparts. Fossil evidence suggests that interspecific competition among carnivores was relatively intense and reveals that some individuals specialized in consuming megaherbivores. To estimate the potential impact of Pleistocene large carnivores, we use both historic and modern data on predator–prey body mass relationships to predict size ranges of their typical and maximum prey when hunting as individuals and in groups. These prey size ranges are then compared with estimates of juvenile and subadult proboscidean body sizes derived from extant elephant growth data. Young proboscideans at their most vulnerable age fall within the predicted prey size ranges of many of the Pleistocene carnivores. Predation on juveniles can have a greater impact on megaherbivores because of their long interbirth intervals, and consequently, we argue that Pleistocene carnivores had the capacity to, and likely did, limit megaherbivore population sizes. PMID:26504224

  20. The impact of large terrestrial carnivores on Pleistocene ecosystems.

    PubMed

    Van Valkenburgh, Blaire; Hayward, Matthew W; Ripple, William J; Meloro, Carlo; Roth, V Louise

    2016-01-26

    Large mammalian terrestrial herbivores, such as elephants, have dramatic effects on the ecosystems they inhabit and at high population densities their environmental impacts can be devastating. Pleistocene terrestrial ecosystems included a much greater diversity of megaherbivores (e.g., mammoths, mastodons, giant ground sloths) and thus a greater potential for widespread habitat degradation if population sizes were not limited. Nevertheless, based on modern observations, it is generally believed that populations of megaherbivores (>800 kg) are largely immune to the effects of predation and this perception has been extended into the Pleistocene. However, as shown here, the species richness of big carnivores was greater in the Pleistocene and many of them were significantly larger than their modern counterparts. Fossil evidence suggests that interspecific competition among carnivores was relatively intense and reveals that some individuals specialized in consuming megaherbivores. To estimate the potential impact of Pleistocene large carnivores, we use both historic and modern data on predator-prey body mass relationships to predict size ranges of their typical and maximum prey when hunting as individuals and in groups. These prey size ranges are then compared with estimates of juvenile and subadult proboscidean body sizes derived from extant elephant growth data. Young proboscideans at their most vulnerable age fall within the predicted prey size ranges of many of the Pleistocene carnivores. Predation on juveniles can have a greater impact on megaherbivores because of their long interbirth intervals, and consequently, we argue that Pleistocene carnivores had the capacity to, and likely did, limit megaherbivore population sizes. PMID:26504224

  1. Scaling of the hydrostatic skeleton in the earthworm Lumbricus terrestris.

    PubMed

    Kurth, Jessica A; Kier, William M

    2014-06-01

    The structural and functional consequences of changes in size or scale have been well studied in animals with rigid skeletons, but relatively little is known about scale effects in animals with hydrostatic skeletons. We used glycol methacrylate histology and microscopy to examine the scaling of mechanically important morphological features of the earthworm Lumbricus terrestris over an ontogenetic size range from 0.03 to 12.89 g. We found that L. terrestris becomes disproportionately longer and thinner as it grows. This increase in the length to diameter ratio with size means that, when normalized for mass, adult worms gain ~117% mechanical advantage during radial expansion, compared with hatchling worms. We also found that the cross-sectional area of the longitudinal musculature scales as body mass to the ~0.6 power across segments, which is significantly lower than the 0.66 power predicted by isometry. The cross-sectional area of the circular musculature, however, scales as body mass to the ~0.8 power across segments, which is significantly higher than predicted by isometry. By modeling the interaction of muscle cross-sectional area and mechanical advantage, we calculate that the force output generated during both circular and longitudinal muscle contraction scales near isometry. We hypothesize that the allometric scaling of earthworms may reflect changes in soil properties and burrowing mechanics with size. PMID:24871920

  2. Terrestrial Energy Storage SPS Systems

    NASA Technical Reports Server (NTRS)

    Brandhorst, Henry W., Jr.

    1998-01-01

    Terrestrial energy storage systems for the SSP system were evaluated that could maintain the 1.2 GW power level during periods of brief outages from the solar powered satellite (SPS). Short-term outages of ten minutes and long-term outages up to four hours have been identified as "typical" cases where the ground-based energy storage system would be required to supply power to the grid. These brief interruptions in transmission could result from performing maintenance on the solar power satellite or from safety considerations necessitating the power beam be turned off. For example, one situation would be to allow for the safe passage of airplanes through the space occupied by the beam. Under these conditions, the energy storage system needs to be capable of storing 200 MW-hrs and 4.8 GW-hrs, respectively. The types of energy storage systems to be considered include compressed air energy storage, inertial energy storage, electrochemical energy storage, superconducting magnetic energy storage, and pumped hydro energy storage. For each of these technologies, the state-of-the-art in terms of energy and power densities were identified as well as the potential for scaling to the size systems required by the SSP system. Other issues addressed included the performance, life expectancy, cost, and necessary infrastructure and site locations for the various storage technologies.

  3. Terrestrial cooling and solar variability

    NASA Technical Reports Server (NTRS)

    Agee, E. M.

    1982-01-01

    Observational evidence from surface temperature records is presented and discussed which suggests a significant cooling trend over the Northern Hemisphere from 1940 to the present. This cooling trend is associated with an increase of the latitudinal gradient of temperature and the lapse rate, as predicted by climate models with decreased solar input and feedback mechanisms. Evidence suggests that four of these 80- to 100-year cycles of global surface temperature fluctuation may have occurred, and in succession, from 1600 to the present. Interpretation of sunspot activity were used to infer a direct thermal response of terrestrial temperature to solar variability on the time scale of the Gleissberg cycle (90 years, an amplitude of the 11-year cycles). A physical link between the sunspot activity and the solar parameter is hypothesized. Observations of sensible heat flux by stationary planetary waves and transient eddies, as well as general circulation modeling results of these processes, were examined from the viewpoint of the hypothesis of cooling due to reduced insolation.

  4. Carbon stabilization on terrestrial landscapes

    NASA Astrophysics Data System (ADS)

    Harden, Jennifer W.; Lawrence, Corey; Trumbore, Susan; O'Donnell, Jonathan; Vanoost, Kristof

    2010-05-01

    While terrestrial climate models view C budgets through time-slices of environmental reconstructions, yet during climate transitions, pervasive geomorphic response to climate likely dictate the direction and magnitude of C exchange. Geomorphic processes therefore act as disturbance events that have the potential to create large feedbacks to climate regulation through carbon burial or carbon release. Quantifying the rates of carbon accumulation in various types of deposits allows us to assess intensities of C burial, whereas the spatial extent and timing of geomorphic processes allows us to quantify the net impact on atmospheric CO2 budgets. Mechanisms and forms of C that are buried or stored lend insights into the longevity of these geomorphic events that dictate land-atmosphere C exchange. Chronosequences of fluvial, loess, and coastal deposits dated by various chronologic tools were used to calculate carbon intensities, or accumulation rates, into soil and deep sediment. Vertical cores of peat and permafrost provide such rates through direct aging of organic carbon preserved in the cores. Rates of input to soil and surface sediment varied by 4 orders of magnitude, which reflects variations in both plant production and decomposition over various timescales of decades to millennia. In general, shallow and shorterm rates are higher than deep, longterm rates. Based on the soil property that best predicts C storage and turnover, we hypothesize different mechanisms of stabilization for selected soil profiles: For example clay content, free iron oxides, freezing temperatures were key in C stabilization within the upper meter of Alfisols, Ultisols, and Cryosols, respectively.

  5. Terrestrial Planet Finder: science overview

    NASA Technical Reports Server (NTRS)

    Unwin, Stephen C.; Beichman, C. A.

    2004-01-01

    The Terrestrial Planet Finder (TPF) seeks to revolutionize our understanding of humanity's place in the universe - by searching for Earth-like planets using reflected light, or thermal emission in the mid-infrared. Direct detection implies that TPF must separate planet light from glare of the nearby star, a technical challenge which has only in recent years been recognized as surmountable. TPF will obtain a low-resolution spectra of each planets it detects, providing some of its basic physical characteristics and its main atmospheric constituents, thereby allowing us to assess the likelihood that habitable conditions exist there. NASA has decided the scientific importance of this research is so high that TPF will be pursued as two complementary space observatories: a visible-light coronagraph and a mid-infrared formation flying interferometer. The combination of spectra from both wavebands is much more valuable than either taken separately, and it will allow a much fuller understanding of the wide diversity of planetary atmospheres that may be expected to exist. Measurements across a broad wavelength range will yield not only physical properties such as size and albedo, but will also serve as the foundations of a reliable and robust assessment of habitability and the presence of life.

  6. Bibliography of terrestrial impact structures

    NASA Astrophysics Data System (ADS)

    Grolier, M. J.

    1985-09-01

    This bibliography lists 105 terrestrial impact structures, of which 12 are proven structures, that is, structures associated with meteorites, and 93 are probable. Of the 93 probable structures, 18 are known to contain rocks with meteoritic components or to be enriched in meteoritic signature-elements, both of which enhance their probability of having originated by impact. Many of the structures investigated in the USSR to date are subsurface features that are completely or partly buried by sedimentary rocks. At least 16 buried impact structures have already been identified in North America and Europe. No proven nor probable submarine impact structure rising above the ocean floor is presently known; none has been found in Antarctica or Greenland. An attempt has been made to cite for each impact structure all literature published prior to mid-1983. The structures are presented in alphabetical order by continent, and their geographic distribution is indicated on a sketch map of each continent in which they occur. They are also listed tables in: (1) alphabetical order, (2) order of increasing latitude, (3) order of decreasing diameter, and (4) order of increasing geologic age.

  7. Bibliography of terrestrial impact structures

    NASA Technical Reports Server (NTRS)

    Grolier, M. J.

    1985-01-01

    This bibliography lists 105 terrestrial impact structures, of which 12 are proven structures, that is, structures associated with meteorites, and 93 are probable. Of the 93 probable structures, 18 are known to contain rocks with meteoritic components or to be enriched in meteoritic signature-elements, both of which enhance their probability of having originated by impact. Many of the structures investigated in the USSR to date are subsurface features that are completely or partly buried by sedimentary rocks. At least 16 buried impact structures have already been identified in North America and Europe. No proven nor probable submarine impact structure rising above the ocean floor is presently known; none has been found in Antarctica or Greenland. An attempt has been made to cite for each impact structure all literature published prior to mid-1983. The structures are presented in alphabetical order by continent, and their geographic distribution is indicated on a sketch map of each continent in which they occur. They are also listed tables in: (1) alphabetical order, (2) order of increasing latitude, (3) order of decreasing diameter, and (4) order of increasing geologic age.

  8. Terrestrial Mobile Mapping: photogrammetric simulator

    NASA Astrophysics Data System (ADS)

    Taglioretti, C.; Manzino, A. M.

    2014-08-01

    Nowadays many types of sensors are used for terrestrial mobile mapping (TMM): IMU, odometers, GNSS, cameras, etc., and it is essential to understand how these sensors can improve the solution in terms of precision, accuracy and reliability. TMM issues are characterized by many variables: vehicle trajectory, the height of the buildings and the distance between them, traffic conditions, the presence or absence of trees, the level of illumination, etc. The aim of this study is to determine how photogrammetric measurements can improve the quality of TMM solution at least concerning magnitude and error propagation when there is no GNSS signal (for example in an urban canyon). Another purpose of the study was to determine the most suitable design project for a specific relief in order to obtain the best possible photogrammetric results. By analyzing the error propagation in the various components of relative orientation along the trajectory and considering a sequence of images characterized by an overlap varying between 60 to 90% and the same number of tie points, results were obtained which confirmed the reliability of the data produced by the simulator. These results are shown in this paper.

  9. Tightly integrated sensor-based terrestrial LiDAR georeferencing

    NASA Astrophysics Data System (ADS)

    Wilkinson, Benjamin E.

    Georeferencing of terrestrial LiDAR scanning data is typically performed by using scanner target points occupying control points in the project area. This necessitates intensive field labor and extra, often cumbersome equipment. A method for georeferencing scan data using two GPS antennas firmly mounted on the optical head of a LiDAR scanner has been developed. By adding a dual GPS antenna apparatus to the scanner setup, thereby supplanting the use of multiple ground control points scattered throughout the project, we mitigate not only the problems associated with georeferencing but also induce a more efficient set up procedure while maintaining a practical level of precision. This study is an extension of the dual GPS antenna method by creating a process for a simultaneous network adjustment of multiple scanner stations. By exploiting additional sensor information from a scanner-mounted camera and point cloud matching techniques, an integrated adjustment of observations from this sensor suite is developed. Further, the technique is tested on two distinct data sets. The testing consists of comparison with conventional techniques and different combinations of the novel, more autonomous methods. Analysis includes the investigation of precision, accuracy, efficiency, and conditioning under different configurations of the system. The test results indicate that centimeter-level accuracy at a scanner-point distance of 40 meters can be achieved using only imagery and scanner-mounted GPS data, and that under certain circumstances, the autonomous methods were able to approach the same level of precision as the conventional data-driven method.

  10. Solar-terrestrial models and application software

    NASA Technical Reports Server (NTRS)

    Bilitza, Dieter

    1990-01-01

    The empirical models related to solar-terrestrial sciences are listed and described which are available in the form of computer programs. Also included are programs that use one or more of these models for application specific purposes. The entries are grouped according to the region of the solar-terrestrial environment to which they belong and according to the parameter which they describe. Regions considered include the ionosphere, atmosphere, magnetosphere, planets, interplanetary space, and heliosphere. Also provided is the information on the accessibility for solar-terrestrial models to specify the magnetic and solar activity conditions.

  11. [Dark respiration of terrestrial vegetations: a review].

    PubMed

    Sun, Jin-Wei; Yuan, Feng-Hui; Guan, De-Xin; Wu, Jia-Bing

    2013-06-01

    The source and sink effect of terrestrial plants is one of the hotspots in terrestrial ecosystem research under the background of global change. Dark respiration of terrestrial plants accounts for a large fraction of total net carbon balance, playing an important role in the research of carbon cycle under global climate change. However, there is little study on plant dark respiration. This paper summarized the physiological processes of plant dark respiration, measurement methods of the dark respiration, and the effects of plant biology and environmental factors on the dark respiration. The uncertainty of the dark respiration estimation was analyzed, and the future hotspots of related researches were pointed out. PMID:24066565

  12. Solar-terrestrial models and application software

    NASA Technical Reports Server (NTRS)

    Bilitza, D.

    1992-01-01

    The empirical models related to solar-terrestrial sciences are listed and described which are available in the form of computer programs. Also included are programs that use one or more of these models for application specific purposes. The entries are grouped according to the region of their solar-terrestrial environment to which they belong and according to the parameter which they describe. Regions considered include the ionosphere, atmosphere, magnetosphere, planets, interplanetary space, and heliosphere. Also provided is the information on the accessibility for solar-terrestrial models to specify the magnetic and solar activity conditions.

  13. Solar Terrestrial Physics: Present and Future

    NASA Technical Reports Server (NTRS)

    Butler, D. M. (Editor); Papadopoulos, K. (Editor)

    1984-01-01

    The following topics relating to solar-terrestrial interactions are considered: (1) reconnection of magnetic fields; (2) particle acceleration; (3) solar magnetic flux; (4) magnetohydrodynamic waves and turbulence in the Sun and interplanetary medium; (5) coupling of the solar wind to the magnetosphere; (6) coronal transients; (7) the connection between the magnetosphere and ionosphere; (8) substorms in the magnetosphere; (9) solar flares and the solar terrestrial environment; (10) shock waves in the solar terrestrial environment; (11) plasma transport and convection at high latitudes; and (12) high latitude ionospheric structure.

  14. 29 CFR 541.604 - Minimum guarantee plus extras.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Minimum guarantee plus extras. 541.604 Section 541.604 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS DEFINING AND DELIMITING THE EXEMPTIONS FOR EXECUTIVE, ADMINISTRATIVE, PROFESSIONAL, COMPUTER AND...

  15. Achieving more with less: Extra milers' behavioral influences in teams.

    PubMed

    Li, Ning; Zhao, Helen H; Walter, Sheryl L; Zhang, Xin-An; Yu, Jia

    2015-07-01

    Teams are composed of individual members who collectively contribute to team success. As a result, contemporary team research tends to focus on how team overall properties (e.g., the average of team personality and behavior) affect team processes and effectiveness while overlooking the potential unique influences of specific members on team outcomes. Drawing on minority influence theory (Grant & Patil, 2012), we extend previous teams research by demonstrating that an extra miler (i.e., a team member exhibiting the highest frequency of extra-role behaviors in a team) can influence team processes and, ultimately, team effectiveness beyond the influences of all the other members. Specifically, based on a field study, we report that the extra miler's behavioral influences (i.e., helping and voice) on team monitoring and backup processes and team effectiveness are contingent on his or her network position in the team, such that the member tends to have stronger influence on team outcomes when he or she is in a central position. We also find that even a single extra miler in a vital position plays a more important role in driving team processes and outcomes than do all the other members. Therefore, our research offers an important contribution to the team literature by demonstrating the disproportionate influences of specific team members on team overall outcomes. PMID:25664471

  16. Extra-Curricular Inequality. Research Brief. Edition 1

    ERIC Educational Resources Information Center

    Sutton Trust, 2014

    2014-01-01

    This Research Briefing analyses Office for National Statistics data and finds children from the most advantaged households benefit from significantly more spending on extra-curricular activities and private tutoring than their poorer peers. The brief also includes the Trust's annual polling on private tuition and new polling on parents and

  17. University Extra-Mural Studies and Extension Outreach: Incompatibilities

    ERIC Educational Resources Information Center

    Rogers, Alan

    2014-01-01

    The argument of this paper is that--within a wide range of university responses to the challenge of outreach--there grew up in the extra-mural or adult education departments of many UK universities an alternative epistemological paradigm to the older and more traditional extension programmes. This paradigm threatened the extension approach and has

  18. Lesson of the Heart: An Extra-Credit Assignment

    ERIC Educational Resources Information Center

    Lehman, Linda L.

    2012-01-01

    Teacher candidates need to have a passion for teaching and a drive to do whatever is necessary even when it is uncomfortable, uncommon, or hard. Such efforts should not be considered extra, but essential. A purposeful, focused enthusiasm for one's students, a belief in their potential, along with heartfelt compassion and the perseverance to work…

  19. CANAL EMERGES FROM EAST SIDE OF MTR BUILDING. "EXTRA" LENGTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CANAL EMERGES FROM EAST SIDE OF MTR BUILDING. "EXTRA" LENGTH WAS TO STORE SPENT FUEL THAT WOULD ACCUMULATE BEFORE THE CHEMICAL PROCESSING PLANT WAS READY TO PROCESS IT. INL NEGATIVE NO. 1659. Unknown Photographer, 3/9/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  20. Anomaly driven signatures of extra U(1)'s

    SciTech Connect

    Antoniadis, Ignatios; Boyarsky, Alexey; Ruchayskiy, Oleg

    2010-02-10

    Anomaly cancellation between different sectors of a theory may mediate new interactions between gauge bosons. Such interactions lead to observable effects both at precision laboratory experiments and at accelerators. Such experiments may reveal the presence of hidden sectors or hidden extra dimensions.

  1. Extra-Curricular Activities and Academic Performance in Secondary Students

    ERIC Educational Resources Information Center

    Moriana, Juan Antonio; Alos, Francisco; Alcala, Rocio; Pino, Maria-Jose; Herruzo, Javier; Ruiz, Rosario

    2006-01-01

    Introduction: In this paper we study the possible influence of extra-curricular activities (study-related and/or sports) on academic performance of first- and second-year pupils in "Educacion Secundaria Obligatoria (ESO)" [N.T. seventh- and eighth-graders]. Method: We randomly selected 12 schools in the city (9 public and 3 private), and randomly

  2. Health-Promoting Physical Activity and Extra-Curricular Sport

    ERIC Educational Resources Information Center

    Curtner-Smith, Matthew; Sofo, Seidu; Chouinard, Jeremy; Wallace, Sheila

    2007-01-01

    The primary purpose of this exploratory study was to determine the percentage of time in which school pupils coached by teachers were engaged in moderate to vigorous physical activity (MVPA) during extra-curricular sport practices. Three secondary purposes of the study were to determine (a) the percentage of time allocated by teachers for pupils…

  3. Are Extra Classes the Success behind High Performance and Marks?

    ERIC Educational Resources Information Center

    Santhi, N.

    2011-01-01

    Extra classes have been a fixture in the educational system in India. They pre-date all existing educational programmes and examinations. Yet more recently the justification and reasons for the maintenance of these classes have been called into question. There have been unsubstantiated claims that in some cases the classes have been "organized" in…

  4. Extra-team Connections for Knowledge Transfer between Staff Teams

    ERIC Educational Resources Information Center

    Ramanadhan, Shoba; Wiecha, Jean L.; Emmons, Karen M.; Gortmaker, Steven L.; Viswanath, Kasisomayajula

    2009-01-01

    As organizations implement novel health promotion programs across multiple sites, they face great challenges related to knowledge management. Staff social networks may be a useful medium for transferring program-related knowledge in multi-site implementation efforts. To study this potential, we focused on the role of extra-team connections (ties

  5. Deconstructing Dimensions: Adventures in Theory Space (Large Extra Dimension)

    SciTech Connect

    Arkani-Hamed, Nima

    2009-11-28

    Theories of gravity and gauge forces in more than four dimensions offer a new paradigm for physics beyond the standard model. We present some of the most interesting recent ideas, and explain how signals for extra dimensions could appear in experiments at a linear e+e- collider.

  6. The Extra Strand of the Maori Science Curriculum

    ERIC Educational Resources Information Center

    Stewart, Georgina

    2011-01-01

    This paper comments on the process of re-development of the Maori-medium Science (Putaiao) curriculum, as part of overall curriculum development in Aotearoa New Zealand. A significant difference from the English Science curriculum was the addition of an "extra strand" covering the history and philosophy of science. It is recommended that this

  7. Lesson of the Heart: An Extra-Credit Assignment

    ERIC Educational Resources Information Center

    Lehman, Linda L.

    2012-01-01

    Teacher candidates need to have a passion for teaching and a drive to do whatever is necessary even when it is uncomfortable, uncommon, or hard. Such efforts should not be considered extra, but essential. A purposeful, focused enthusiasm for one's students, a belief in their potential, along with heartfelt compassion and the perseverance to work

  8. Chemical changes in extra virgin argan oil after thermal treatment.

    PubMed

    Gharby, Sad; Harhar, Hicham; Kartah, Badr Eddine; Guillaume, Dom; Charrouf, Zoubida

    2013-01-01

    Physicochemical parameters, measured every 6 hours, of extra virgin argan oil heated for 24 h at 180 degrees C were investigated and compared with those of five other edible oils treated in the same thermoxidative condition. Argan oil was found to be particularly stable at high temperature, its level of polar compounds remaining low even after 24 h of heating. PMID:23472453

  9. Extra-lobar Pulmonary Sequestration Requiring Intrauterine Thoracentesis

    PubMed Central

    Kahvecioglu, Dilek; Alan, Serdar; Yildiz, Duran; Akduman, Hasan; Erdeve, Omer; Bahadir, Gulnur Gollu; Kologlu, Meltem; Atasay, Begum; Arsan, Saadet

    2015-01-01

    Congenital lung malformations can result in significant morbidity and mortality in children. Pulmonary sequestration is an uncommon congenital malformation of the lung that can cause complications even in fetal life. We herein present a newborn with extra-lobar sequestration (ELS) that lead to hydrops fetalis necessitating fetal intervention. PMID:25628992

  10. Extra-lobar Pulmonary Sequestration Requiring Intrauterine Thoracentesis.

    PubMed

    Cakir, Ufuk; Kahvecioglu, Dilek; Alan, Serdar; Yildiz, Duran; Akduman, Hasan; Erdeve, Omer; Bahadir, Gulnur Gollu; Kologlu, Meltem; Atasay, Begum; Arsan, Saadet

    2015-01-01

    Congenital lung malformations can result in significant morbidity and mortality in children. Pulmonary sequestration is an uncommon congenital malformation of the lung that can cause complications even in fetal life. We herein present a newborn with extra-lobar sequestration (ELS) that lead to hydrops fetalis necessitating fetal intervention. PMID:25628992

  11. Charged current unitarity and extra neutral gauge bosons

    SciTech Connect

    Marciano, W.J.; Sirling, A.

    1987-03-01

    The experimental status of the Kobayashi-Maskawa-Cabibbo (KMC) matrix is surveyed and shown to provide a precision test of the standard model at the level of its O(..cap alpha..) radiative corrections. Implications for new physics and constraints of extra neutral gauge bosons are described. 12 refs., 1 fig.

  12. Are Extra Classes the Success behind High Performance and Marks?

    ERIC Educational Resources Information Center

    Santhi, N.

    2011-01-01

    Extra classes have been a fixture in the educational system in India. They pre-date all existing educational programmes and examinations. Yet more recently the justification and reasons for the maintenance of these classes have been called into question. There have been unsubstantiated claims that in some cases the classes have been "organized" in

  13. Extra-Curricular Activities and Academic Performance in Secondary Students

    ERIC Educational Resources Information Center

    Moriana, Juan Antonio; Alos, Francisco; Alcala, Rocio; Pino, Maria-Jose; Herruzo, Javier; Ruiz, Rosario

    2006-01-01

    Introduction: In this paper we study the possible influence of extra-curricular activities (study-related and/or sports) on academic performance of first- and second-year pupils in "Educacion Secundaria Obligatoria (ESO)" [N.T. seventh- and eighth-graders]. Method: We randomly selected 12 schools in the city (9 public and 3 private), and randomly…

  14. 8. LESLIE WICKMAN, EVA (EXTRA VEHICULAR ACTIVITIES) SPECIALIST, GETTING OUT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. LESLIE WICKMAN, EVA (EXTRA VEHICULAR ACTIVITIES) SPECIALIST, GETTING OUT OF SPACE SUIT AFTER TESTING IN NEUTRAL BUOYANCY TANK. AVERAGE COST OF SUIT $1,000,000. - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

  15. Textual, Contextual, and Extra-Contextual Knowledge in ESL Composition.

    ERIC Educational Resources Information Center

    Zhao, Heping

    Victor Raskin's taxonomy of knowledge, based on semantics theory, is adapted and applied to composition in English as a Second Language (ESL). Raskin's classification of knowledge as linguistic and encyclopedic is converted to a continuum from textual to extra-contextual, with contextual knowledge situated between the two. Textual knowledge is

  16. Visualization: Is It More than Extra-Attention?

    ERIC Educational Resources Information Center

    Ayres, Joe; Hopf, Theodore S.

    1989-01-01

    Examines how visualization compares with placebo procedures in reducing communication apprehension (CA) in public speaking classes. Finds that visualization is an active treatment procedure that reduces CA above and beyond the reduction that can be attributed to the "extra-attention" involved in any treatment process. (MS)

  17. Extra-Solar Planetary Imager (ESPI) for Space Based Jovian Planetary Detection

    NASA Technical Reports Server (NTRS)

    Lyon, Rick G.; Melnick, Gary J.; Nisenson, Peter; Papaliolios, Costa; Ridgeway, Steve; Friedman, Edward; Gezari, Dan Y.; Harwit, Martin; Graf, Paul

    2002-01-01

    We report on out Extra-Solar Planetary Imager (ESPI) study for a recent Midex (NASA Medium Class Explorer Mission) proposal. Proposed for ESPI was a 1.5 x 1.5 square meter Jacquinot apodized square aperture telescope. The combination of apodization and a square aperture telescope significantly reduces the diffracted light from a bright central source over much of the telescope focal plane. As a result, observations of very faint astronomical objects next to bright sources with angular separations as small as 0.32 arcseconds become possible. This permits a sensitive search for exo-planets in reflected light. The system is capable of detecting a Jupiter-like planet in a relatively long-period orbit around as many as 160 to 175 stars with a signal-to-noise ratio greater than 5 in observations lasting maximally 100 hours per star. We discuss the effects of wavefront error, mirror speckle, pointing error and signal-to-noise issues, as well as the scalability of our ESPI study with respect to NASA's Terrestrial Planet Finder mission.

  18. Extra-solar planetary imager (ESPI) for space-based Jovian planetary detection

    NASA Astrophysics Data System (ADS)

    Lyon, Richard G.; Gezari, Daniel Y.; Melnick, Gary J.; Nisenson, Peter; Papaliolios, Costas D.; Ridgway, Stephen T.; Friedman, Edward J.; Harwit, Martin; Graf, Paul

    2003-02-01

    The Extra-Solar Planetary Imager (ESPI) is envisioned as a space based, high dynamic range, visible imager capable of detecting Jovian like planets. Initially proposed as a NASA Midex (NASA/Medium Class Explorer) mission (PI:Gary Melnick), as a space-based 1.5 x 1.5 m2 Jacquinot apodized square aperture telescope. The combination of apodization and a square aperture telescope reduces the diffracted light from a bright central source increasing the planetary to stellar contrast over much of the telescope focal plane. As a result, observations of very faint astronomical objects next to bright sources with angular separations as small as 0.32 arcseconds become possible. This permits a sensitive search for exo-planets in reflected light. ESPI is capable of detecting a Jupiter-like planet in a relatively long-period orbit around as many as 160 to 175 stars with a signal-to-noise ratio > 5 in observations lasting maximally 100 hours per star out to ~16 parsecs. We discuss the scientific ramifications, an overview of the system design including apodizing a square aperture, signal to noise issues and the effect of wavefront errors and the scalability of ESPI with respect to NASA's Terrestrial Planet Finder mission.

  19. Extra-tropical Cyclones and Windstorms in Seasonal Forecasts

    NASA Astrophysics Data System (ADS)

    Leckebusch, Gregor C.; Befort, Daniel J.; Weisheimer, Antje; Knight, Jeff; Thornton, Hazel; Roberts, Julia; Hermanson, Leon

    2015-04-01

    Severe damages and large insured losses over Europe related to natural phenomena are mostly caused by extra-tropical cyclones and their related windstorm fields. Thus, an adequate representation of these events in seasonal prediction systems and reliable forecasts up to a season in advance would be of high value for society and economy. In this study, state-of-the-art seasonal forecast prediction systems are analysed (ECMWF, UK Met Office) regarding the general climatological representation and the seasonal prediction of extra-tropical cyclones and windstorms during the core winter season (DJF) with a lead time of up to four months. Two different algorithms are used to identify cyclones and windstorm events in these datasets. Firstly, we apply a cyclone identification and tracking algorithm based on the Laplacian of MSLP and secondly, we use an objective wind field tracking algorithm to identify and track continuous areas of extreme high wind speeds (cf. Leckebusch et al., 2008), which can be related to extra-tropical winter cyclones. Thus, for the first time, we can analyse the forecast of severe wind events near to the surface caused by extra-tropical cyclones. First results suggest a successful validation of the spatial climatological distributions of wind storm and cyclone occurrence in the seasonal forecast systems in comparison with reanalysis data (ECMWF-ERA40 & ERAInterim) in general. However, large biases are found for some areas. The skill of the seasonal forecast systems in simulating the year-to-year variability of the frequency of severe windstorm events and cyclones is investigated using the ranked probability skill score. Positive skill is found over large parts of the Northern Hemisphere as well as for the most intense extra-tropical cyclones and its related wind fields.

  20. Evidence for allelism of the recessive insertional mutation add and the dominant mouse mutation extra-toes (Xt).

    PubMed

    Pohl, T M; Mattei, M G; Rther, U

    1990-12-01

    A recessive mutant caused by insertional mutagenesis in transgenic mice has been detected in which the anterior part of the forelimb is disorganized. The morphology of the thumb is always altered and sometimes the adjacent finger has an extra phalanx. This phenotype suggests that a body plan gene is affected. We have named the mutation add (anterior digit-pattern deformity). Using the cloned DNA from the flanking region of the integrated transgene, add has been mapped close to the centromere of chromosome 13. This position links add to a genetically mapped locus called extra-toes (Xt). The phenotype of the double-mutant add/Xt as well as the molecular analysis suggest that add and Xt are allelic. PMID:1983115

  1. Possible climates on terrestrial exoplanets.

    PubMed

    Forget, F; Leconte, J

    2014-04-28

    What kind of environment may exist on terrestrial planets around other stars? In spite of the lack of direct observations, it may not be premature to speculate on exoplanetary climates, for instance, to optimize future telescopic observations or to assess the probability of habitable worlds. To begin with, climate primarily depends on (i) the atmospheric composition and the volatile inventory; (ii) the incident stellar flux; and (iii) the tidal evolution of the planetary spin, which can notably lock a planet with a permanent night side. The atmospheric composition and mass depends on complex processes, which are difficult to model: origins of volatiles, atmospheric escape, geochemistry, photochemistry, etc. We discuss physical constraints, which can help us to speculate on the possible type of atmosphere, depending on the planet size, its final distance for its star and the star type. Assuming that the atmosphere is known, the possible climates can be explored using global climate models analogous to the ones developed to simulate the Earth as well as the other telluric atmospheres in the solar system. Our experience with Mars, Titan and Venus suggests that realistic climate simulators can be developed by combining components, such as a 'dynamical core', a radiative transfer solver, a parametrization of subgrid-scale turbulence and convection, a thermal ground model and a volatile phase change code. On this basis, we can aspire to build reliable climate predictors for exoplanets. However, whatever the accuracy of the models, predicting the actual climate regime on a specific planet will remain challenging because climate systems are affected by strong positive feedbacks. They can drive planets with very similar forcing and volatile inventory to completely different states. For instance, the coupling among temperature, volatile phase changes and radiative properties results in instabilities, such as runaway glaciations and runaway greenhouse effect. PMID:24664919

  2. Terrestrial isopods -- a good choice for toxicity testing of pollutants in the terrestrial environment

    SciTech Connect

    Drobne, D.

    1997-06-01

    Terrestrial isopods are suitable invertebrates for testing the relative toxicities of chemicals present in the terrestrial environment. Terrestrial isopods respond in numerous ways to elevated concentrations of chemicals in their food, but only a few of these responses can be used as toxicological endpoints. The most suitable are changes in reproduction, food consumption, moult cycle duration, and structure of the digestive glands. These responses are able to provide accurate indications of sublethal toxicity. Toxicity tests with terrestrial isopods could be much more reliable through the use of positive controls. A positive control with a reference toxicant could also be supplemented by a reference endpoint. The most suitable reference endpoint is change of food consumption rate. Toxicity testing with terrestrial isopods is a very promising method for fast, routine, and inexpensive laboratory determination of the relative toxicities of chemicals in the terrestrial environment.

  3. Terrestrial analogs of the Hellespontus dunes, Mars

    NASA Technical Reports Server (NTRS)

    Breed, C. S.

    1977-01-01

    Geomorphic features in the Hellespontus region, Mars, were compared with dunes of the crescentic ridge type in numerous terrestrial sand seas quantitatively by dimensional analysis of dune lengths, widths, and wavelengths. Mean values for the Hellespontus dunes are close to mean values derived from measurements of all sampled terrestrial sand seas. Terrestrial analogs of form and areal distribution of the Hellespontus dunes are shown by comparison of scale ratios derived from the measurements. Dunes of similar form occur in South West Africa, in Pakistan, in the southeastern Arabian peninsula, in the Sahara, in eastern USSR and northern China, and in western North America. Terrestrial analogs closest to form and areal distribution of the Hellespontus dunes are in the Kara Kum Desert, Turkmen SSR, and in the Ala Shan (Gobi) Desert, China.

  4. The Geology of the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    Carr, M. H. (Editor); Saunders, R. S.; Strom, R. G.; Wilhelms, D. E.

    1984-01-01

    The geologic history of the terrestrial planets is outlined in light of recent exploration and the revolution in geologic thinking. Among the topics considered are planet formation; planetary craters, basins, and general surface characteristics; tectonics; planetary atmospheres; and volcanism.

  5. Space Vehicle Terrestrial Environment Design Requirements Guidelines

    NASA Technical Reports Server (NTRS)

    Johnson, Dale L.; Keller, Vernon W.; Vaughan, William W.

    2006-01-01

    The terrestrial environment is an important driver of space vehicle structural, control, and thermal system design. NASA is currently in the process of producing an update to an earlier Terrestrial Environment Guidelines for Aerospace Vehicle Design and Development Handbook. This paper addresses the contents of this updated handbook, with special emphasis on new material being included in the areas of atmospheric thermodynamic models, wind dynamics, atmospheric composition, atmospheric electricity, cloud phenomena, atmospheric extremes, and sea state. In addition, the respective engineering design elements are discussed relative to terrestrial environment inputs that require consideration. Specific lessons learned that have contributed to the advancements made in the application and awareness of terrestrial environment inputs for aerospace engineering applications are presented.

  6. Terrestrial passage theory of the moon illusion.

    PubMed

    Reed, C F

    1984-12-01

    Theories of the celestial, or moon, illusion have neglected geometric characteristics of movement along and above the surface of the earth. The illusion occurs because the characteristics of terrestrial passage are attributed to celestial passage. In terrestrial passage, the visual angle subtended by an object changes discriminably as an essentially invariant function of elevation above the horizon. In celestial passage, by contrast, change in visual angle is indiscriminable at all elevations. If a terrestrial object gains altitude, its angular subtense fails to follow the expansion projected for an orbital course: Angular diminution or constancy is equivalent to distancing. On the basis of terrestrial projections, a similar failure of celestial objects in successive elevations is also equivalent to distancing. The illusion occurs because of retinal image constancy, not--as traditionally stated--despite it. PMID:6240520

  7. Recommended architectures for the Terrestrial Planet Finder

    NASA Technical Reports Server (NTRS)

    Beichman, C.

    2004-01-01

    The primary conclusion from an intensive, two year period of study is that with suitable technology investment, starting now, a mission to detect terrestrial planets around nearby stars could be launched within a decade.

  8. AIR POLLUTION EFFECTS ON TERRESTRIAL ECOSYSTEMS

    EPA Science Inventory

    This report presents information on the effects of ozone, nitrogen oxides, sulfur oxides, particulate matter, and acidic disposition on terrestrial ecosystems. A brief explanation of ecosystem dynamics is presented to provide a framework for discussion of air pollutant effects. D...

  9. Thermoluminescence of meteorites and their terrestrial ages

    NASA Astrophysics Data System (ADS)

    Melcher, C. L.

    1981-05-01

    A technique for determining chondritic meteorite terrestrial ages based on the measurement of a normalized thermoluminescence (TL) is presented and applied to samples of 11 recently discovered Antarctic meteorites. Measurements of TL levels normalized to individual meteorite TL sensitivities are presented for 45 chondrites of known terrestrial ages and shown to increase with decreasing terrestrial age. Differences in TL levels in meteorites of the same terrestrial ages are attributed to differences in orbital temperatures. TL levels determined in initial rise experiments for the Antarctic meteorites are found to indicate ages which show a rough correlation with those deduced from C-14, Al-26 and Cl-36 studies. Due to the rapidity and low material requirements of TL measurements, it is proposed that TL determinations be used as screening process to select the most interesting samples for further study by other, more exact, techniques.

  10. Global Change and the Terrestrial Biosphere

    SciTech Connect

    Rogers, Alistair

    2009-04-22

    Terrestrial ecosystems sustain life on Earth through the production of food, fuel, fiber, clean air, and naturally purified water. But how will agriculture and ecosystems be affected by global change? Rogers describes the impact of projected climate change on the terrestrial biosphere and explains why plants are not just passive respondents to global change, but play an important role in determining the rate of change.

  11. The Compositional Diversity of Extrasolar Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Carter-Bond, J. C.; O'Brien, D. P.

    2011-12-01

    The details of the formation of the terrestrial planets are long-standing questions in the geological, planetary and astronomical sciences, with the discovery of extrasolar planetary systems placing even greater emphasis on these questions. Here we present simulations of the bulk compositions of simulated terrestrial planets in extrasolar planetary systems. These simulations incorporate both giant planet migration into the dynamical simulations and a variety of ices, clathrates and hydrates into the chemical modeling, providing us with a more inclusive view of extrasolar terrestrial planet formation. We find that a diverse range of extrasolar terrestrial planets are produced, ranging from bulk elemental compositions similar to that of Earth to those that are enriched in elements such as C and Si, producing planets with compositions unlike anything we have previously observed. Giant planet migration significantly alters the composition of the final terrestrial planet by redistributing material throughout the system. Simulated terrestrial planets produced within the migration simulations are found to contain larger amounts of Mg-silicate species and hydrous material. These variations in composition will greatly influence planetary processes such as plate tectonics, planetary interior structure and the primary atmospheric composition.

  12. Update on terrestrial ages of Antarctic meteorites

    SciTech Connect

    Welten, K C; Nishiizumi, K; Caffee, M W

    2000-01-14

    Terrestrial ages of Antarctic meteorites are one of the few parameters that will help us to understand the meteorite concentration mechanism on blue-ice fields. Traditionally, terrestrial ages were determined on the basis of {sup 36}Cl in the metal phase, which has an uncertainty of about 70 ky. For young meteorites (< 40 ky), the terrestrial age is usually and most accurately determined using {sup 14}C in the stone phase. In recent years two methods have been developed which are independent of shielding effects, the {sup 10}Be-{sup 36}Cl/{sup 10}Be method and the {sup 41}Ca/{sup 36}Cl method. These methods have reduced the typical uncertainties in terrestrial ages by a factor of 2, to about 30 ky. The {sup 10}Be-{sup 36}Cl/{sup 10}Be method is quite dependent on the exposure age, which is unknown for most Antarctic meteorites. The authors therefore also attempt to use the relation between {sup 26}Al and {sup 36}Cl/{sup 26}Al to derive a terrestrial age less dependent on the exposure age. The authors have measured the concentrations of cosmogenic {sup 10}Be, {sup 26}Al and {sup 36}Cl in the metal phase of {approximately} 70 Antarctic meteorites, from more than 10 different ice-fields, including many new ones. They then discuss the trends in terrestrial ages of meteorites from different ice-fields.

  13. The effect of melting and crustal production on plate tectonics on terrestrial planets

    NASA Astrophysics Data System (ADS)

    Lourenço, Diogo; Tackley, Paul

    2013-04-01

    In the Solar System, Earth is the only planet to be in a mobile-lid regime, whilst it is generally accepted that all the other terrestrial planets are currently in a stagnant-lid regime, showing little or no surface motion. A transitional regime between these two, showing episodic overturns of an unstable stagnant lid, is also possible and has been proposed for Venus (e.g. Armann and Tackley, JGR 2012). In recent years a number of studies have focused on the feasibility of plate tectonics on large (1-10 Earth masses) extra-solar terrestrial planets; so-called super-Earths, with some studies concluding that these bodies should be in a mobile-regime mode (Valencia et al., ApJ 2007; van Heck and Tackley, EPSL 2011), but others predicting that they should be in a stagnant-lid regime (O'Neill and Leonardic, GRL 2007; Stein et al., GRL 2011). Using plastic yielding to self-consistently generate plate tectonics on an Earth-like planet with strongly temperature-dependent viscosity is now well-established, but such models typically focus on purely thermal convection, whereas compositional variations in the lithosphere can alter the stress state and greatly influence the likelihood of plate tectonics. For example, Rolf and Tackley (GRL, 2011) showed that the addition of a continent can reduce the critical yield stress for mobile-lid behaviour by a factor of ~2, while Armann and Tackley (JGR, 2012) found that bursts of crustal production caused by partial melting my trigger lithospheric overturn events, suggesting that laterally-heterogeneous crustal production in earlier studies (e.g. papers by Nakagawa and Tackley) may also play an important role in facilitating plate tectonics. Complicating matters is the finding that the final state of the system (stagnant- or mobile-lid) can depend on initial condition (Tackley, G3 2000 - part 2); Weller and Lenardic (GRL, 2012) found that the parameter range in which two solutions are obtained increases with viscosity contrast, leading to Lenardic and Crowley (ApJ, 2012) proposing a bistability of the system, introducing bifurcation theory to predict the tectonic state of a planet. Here we thus test (i) whether melting-induced crustal production changes the critical yield stress needed to obtain mobile-lid behaviour as a function of governing parameters (particularly Rayleigh number and viscosity contrast (Moresi and Solomatov, GJI 1998) as well as internal heating rate), and (ii) whether, under these conditions, there is an initial-condition dependence (bimodality) to the state of the system Weller and Lenardic (GRL, 2012). We study these using StagYY (Tackley, PEPI 2008), which uses a finite-volume scheme for advection of temperature, a multigrid solver to obtain a velocity-pressure solution at each timestep, tracers to track composition, and a treatment of partial melting and crustal formation.

  14. Phosphatidylcholine composition of pulmonary surfactant from terrestrial and marine diving mammals.

    PubMed

    Gutierrez, Danielle B; Fahlman, Andreas; Gardner, Manuela; Kleinhenz, Danielle; Piscitelli, Marina; Raverty, Stephen; Haulena, Martin; Zimba, Paul V

    2015-06-01

    Marine mammals are repeatedly exposed to elevated extra-thoracic pressure and alveolar collapse during diving and readily experience alveolar expansion upon inhalation - a unique capability as compared to terrestrial mammals. How marine mammal lungs overcome the challenges of frequent alveolar collapse and recruitment remains unknown. Recent studies indicate that pinniped lung surfactant has more anti-adhesive components compared to terrestrial mammals, which would aid in alveolar opening. However, pulmonary surfactant composition has not yet been investigated in odontocetes, whose physiology and diving behavior differ from pinnipeds. The aim of this study was to investigate the phosphatidylcholine (PC) composition of lung surfactants from various marine mammals and compare these to a terrestrial mammal. We found an increase in anti-adhesive PC species in harp seal (Pagophilus groenlandicus) and California sea lion (Zalophus californianus) compared to dog (Canus lupus familiaris), as well as an increase in the fluidizing PCs 16:0/14:0 and 16:0/16:1 in pinnipeds compared to odontocetes. The harbor porpoise (a representative of the odontocetes) did not have higher levels of fluidizing PCs compared to dog. Our preliminary results support previous findings that pinnipeds may have adapted unique surfactant compositions that allow them to dive at high pressures for extended periods without adverse effects. Future studies will need to investigate the differences in other surfactant components to fully assess the surfactant composition in odontocetes. PMID:25812797

  15. Terrestrial teleconnections link global rivers

    NASA Astrophysics Data System (ADS)

    O'Loughlin, F.; Howden, N. J.; Woods, R. A.; Bates, P. D.

    2013-12-01

    We present analyses of river discharge data from across the world, which we used to identify links between annual river flow regimes across different continents. Our hypothesis was that, as atmospheric processes are subject to large-scale teleconnection patterns, and because these atmospheric processes are inherently linked to precipitation regimes across the world, there should be identifiable links between river flow regimes driven by these atmospheric processes. We used discharge data from the Global Runoff Data Centre (GRDC) to identify cross-correlations (and accounted for serial dependence) between 23 of the world's largest river basins where overlapping data were available over a period of 12 years or more: two in South America; five in Africa; one in Australasia; five in North America and ten in Eurasia. The selected river basins drain approximately a third of the Earth's landmass at their furthest downstream gauging station. Where significant cross-correlations were found, we compared these to known patterns associated with the ENSO and NAO teleconnections. In total, 85 of the 253 possible correlations were deemed significant at p<0.05, this reduced to 36 at p<0.01 and 21 at p<0.001. Of the significant correlations (p<0.05), 22 were classified as strong (r ? 0.5), 45 as moderate (0.5< r ?0.25) and 18 as weak (0.25< r >0). We compared these significant cross-correlations with known atmospheric teleconnection patterns, and while these were consistent for the majority of cases, we found a number of significant correlations that are inconsistent with the anticipated effects of known atmospheric teleconnections. Our results provide new insight into the inter-continental links between global river systems and the way in which these are controlled by large-scale atmospheric processes. We suggest this may be useful for global industries, such as insurers or aid agencies, who seek to understand correlations between the magnitudes of extreme events across different regions of the world. For the former, this may enable more efficient management of global liabilities, for the latter it may enable better logistical planning of disaster relief requirements. Aside from these practical applications, the results also suggest teleconnections exist between terrestrial, as well as ocean and atmospheric water systems.

  16. Early Formation of Terrestrial Crust

    NASA Astrophysics Data System (ADS)

    Harrison, T. M.; Schmitt, A. K.; McCulloch, M. T.; Lovera, O. M.

    2007-12-01

    Early (≥4.5 Ga) Formation of Terrestrial Crust T.M. Harrison1, A.K. Schmitt1, M.T. McCulloch2, and O.M. Lovera1 1Department of Earth and Space Sciences and IGPP, UCLA, Los Angeles, CA 90095, USA; 2Research School of Earth Sciences, Australian National University, Canberra, A.C.T. 2601 AUSTRALIA Large deviations in ǎrepsilonHf(T) from bulk silicate Earth seen in >4 Ga detrital zircons from Jack Hills, Western Australia, have been interpreted as reflecting a major differentiation of the silicate Earth at ca. 4.4 to 4.5 Ga. We have expanded the characterization of 176Hf/177Hf (Hf) in Hadean zircons by acquiring a further 116 laser ablation Lu-Hf measurements on 87 grains with ion microprobe 207Pb/206Pb ages up to 4.36 Ga. Most measurements employed concurrent Lu-Hf and 207Pb/206Pb analyses, permitting assessment of the use of ion microprobe data to characterize the age of the volumetrically larger domain sampled by laser drilling. Our new results confirm and extend the earlier observation of significant negative deviations in ǎrepsilonHf(T) throughout the Hadean, although no positive ǎrepsilonHf(T) values were documented in this study. These data yields an essentially uniform spectrum of single-stage model ages between 4.54 and 4.20 Ga for extraction of the zircons' protoliths from a chondritic reservoir. We derived the full error propagation expression for a parameter, ǎrepsilono, which measures the difference of a sample from solar system initial (Hf) (Hfo), and from this conclude that data plotting close to (Hfo), are statistically meaningful and consistent with silicate differentiation at 4.540±0.006 Ga. δ18O and Ti thermometry for these Hadean zircons show little obvious correlation with initial (Hf), consistent with their derivation through fusion of a broad suite of crustal rock types under near water-saturated conditions. Together with the inclusion assemblage and other isotopic and trace element data obtained from these ancient zircons, our results indicate essentially continuous derivation of crust from the mantle from 4.5 to 4.2 Ga, concurrent with recycling into the mantle and internal crustal re-working. These results represent further evidence that by 4.35 Ga, portions of the crust had taken on continental characteristics.

  17. Groundwater and Terrestrial Water Storage

    NASA Technical Reports Server (NTRS)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of each month of the year) excluding Greenland and Antarctica. The two figures show that 2010 was the driest year since 2003. The drought in the Amazon was largely responsible, but an excess of water in 2009 seems to have buffered that drought to some extent. The drying trend in the 25-55 deg S zone is a combination of Patagonian glacier melt and drought in parts of Australia.

  18. Extracting Extra-Telomeric Phenotypes from Telomerase Mouse Models

    PubMed Central

    Ali, Muhammad

    2014-01-01

    Telomerase reverse transcriptase (TERT) is the protein component of telomerase and combined with an RNA molecule, telomerase RNA component, forms the telomerase enzyme responsible for telomere elongation. Telomerase is essential for maintaining telomere length from replicative attrition and thus contributes to the preservation of genome integrity. Although diverse mouse models have been developed and studied to prove the physiological roles of telomerase as a telomere-elongating enzyme, recent studies have revealed non-canonical TERT activities beyond telomeres. To gain insights into the physiological impact of extra-telomeric roles, this review revisits the strategies and phenotypes of telomerase mouse models in terms of the extra-telomeric functions of telomerase. PMID:24339280

  19. [The place of extra-corporeal oxygenation in pulmonary diseases].

    PubMed

    Le Guen, M; Parquin, F

    2015-04-01

    Extra-corporeal membrane oxygenation (ECMO) effectively replaces the lung in providing oxygenation and carbon dioxide (CO2) removal. For some years, and in parallel to the H1N1 influenza pandemic, this technique has gained interest in relation to significant technological improvements, leading to new concepts of "awake and mobile ECMO" or rehabilitation with ECMO. Finally, the publication of randomized controlled trials giving encouraging results in the adult respiratory distress syndrome (ARDS) has helped to validate this technique and further studies are warranted. This general review aims to outline the definition, classification and principles of ECMO and to give some current information about the indications and possibilities of the technique to the pulmonologist and intensivist. Further possible uses for this technique include extra-corporeal removal of CO2 during hypercapnic respiratory failure and assistance during lung transplantation from the preoperative to the early postoperative period. PMID:25957015

  20. Extra dimensions and neutrinoless double beta decay experiments

    SciTech Connect

    Gozdz, Marek; Kaminski, Wieslaw A.; Faessler, Amand

    2005-05-01

    The neutrinoless double beta decay is one of the few phenomena, belonging to the nonstandard physics, which is extensively being sought for in experiments. In the present paper the link between the half-life of the neutrinoless double beta decay and theories with large extra dimensions is explored. The use of the sensitivities of currently planned 0{nu}2{beta} experiments: DAMA, CANDLES, COBRA, DCBA, CAMEO, GENIUS, GEM, MAJORANA, MOON, CUORE, EXO, and XMASS, gives the possibility for a nondirect 'experimental' verification of various extra dimensional scenarios. We discuss also the results of the Heidelberg-Moscow Collaboration. The calculations are based on the Majorana neutrino mass generation mechanism in the Arkani-Hamed-Dimopoulos-Dvali model.

  1. Detecting extra dimensions by Hydrogen-like atoms

    NASA Astrophysics Data System (ADS)

    Wan-Ping, Zhou; Peng, Zhou; Hao-Xue, Qiao

    2015-01-01

    We reconsider the idea in spectroscopy of detecting extra dimensions by regarding the nucleus as a homogeneous sphere. In our results, it turns out that the gravitational potential inside the nucleus is much stronger than the potential induced by a particle in the same regime in ref. [16], and thus a more significant correction of the ground state energy of hydrogen-like atoms is obtained, which can be used to determine the existence of ADD's extra dimensions. In order to get a larger order of magnitude for the correction, it is better to apply our theory to high-Z atoms or muonic atoms, where the volume of the nucleus can't be ignored and the relativistic effect is important. Our work is based on the Dirac equation in aweak gravity field, and the result is more precise.

  2. Extra-Renal Manifestations of Complement-Mediated Thrombotic Microangiopathies

    PubMed Central

    Hofer, Johannes; Rosales, Alejandra; Fischer, Caroline; Giner, Thomas

    2014-01-01

    Thrombotic microangiopathies (TMA) are rare but severe disorders, characterized by endothelial cell activation and thrombus formation leading to hemolytic anemia, thrombocytopenia, and organ failure. Complement over activation in combination with defects in its regulation is described in an increasing number of TMA and if primary for the disease denominated as atypical hemolytic-uremic syndrome. Although TMA predominantly affects the renal microvasculature, extra-renal manifestations are observed in 20% of patients including involvement of the central nerve system, cardiovascular system, lungs, skin, skeletal muscle, and gastrointestinal tract. Prompt diagnosis and treatment initiation are therefore crucial for the prognosis of disease acute phase and the long-term outcome. This review summarizes the available evidence on extra-renal TMA manifestations and discusses the role of acute and chronic complement activation by highlighting its complex interaction with inflammation, coagulation, and endothelial homeostasis. PMID:25250305

  3. Dark energy, scalar-tensor gravity, and large extra dimensions

    SciTech Connect

    Kainulainen, Kimmo; Sunhede, Daniel

    2006-04-15

    We explore in detail a dilatonic scalar-tensor theory of gravity inspired by large extra dimensions, where a radion field from compact extra dimensions gives rise to quintessence in our 4-dimensional world. We show that the model can give rise to other types of cosmologies as well, some more akin to k-essence and possibly variants of phantom dark energy. In our model the field (or radius) stabilization arises from quantum corrections to the effective 4D Ricci scalar. We then show that various constraints nearly determine the model parameters, and give an example of a quintessence-type cosmology consistent with observations. We show that the upcoming SNAP-experiment would easily distinguish the present model from a constant {lambda} model with an equal amount of dark energy, but that the SNAP-data alone will not be able distinguish it from a {lambda} model with about 5% less dark energy.

  4. Equivariant Reduction of Gauge Theories over Fuzzy Extra Dimensions

    NASA Astrophysics Data System (ADS)

    Krko?lu, Sekin

    2012-02-01

    In SU(N) Yang-Mills theories on a manifold M, which are suitably coupled to a set of scalars, fuzzy spheres may be generated as extra dimensions by spontaneous symmetry breaking. This process results in gauge theories over the product space of the manifold M and the fuzzy spheres with smaller gauge groups. Here we present the SU(2)- and SU(2) SU(2)-equivariant parametrization of U(2) and U(4) gauge fields on S2F and S2F S2F respectively and outline the dimensional reduction of these theories over the fuzzy extra dimensions. The emerging dimensionally reduced theories are Higgs type models. Some vortex type solutions of these theories are briefly discussed.

  5. MODIS-Derived Terrestrial Primary Production

    NASA Astrophysics Data System (ADS)

    Zhao, Maosheng; Running, Steven; Heinsch, Faith Ann; Nemani, Ramakrishna

    Temporal and spatial changes in terrestrial biological productivity have a large impact on humankind because terrestrial ecosystems not only create environments suitable for human habitation, but also provide materials essential for survival, such as food, fiber and fuel. A recent study estimated that consumption of terrestrial net primary production (NPP; a list of all the acronyms is available in the appendix at the end of the chapter) by the human population accounts for about 14-26% of global NPP (Imhoff et al. 2004). Rapid global climate change is induced by increased atmospheric greenhouse gas concentration, especially CO2, which results from human activities such as fossil fuel combustion and deforestation. This directly impacts terrestrial NPP, which continues to change in both space and time (Melillo et al. 1993; Prentice et al. 2001; Nemani et al. 2003), and ultimately impacts the well-being of human society (Milesi et al. 2005). Additionally, substantial evidence show that the oceans and the biosphere, especially terrestrial ecosystems, currently play a major role in reducing the rate of the atmospheric CO2 increase (Prentice et al. 2001; Schimel et al. 2001). NPP is the first step needed to quantify the amount of atmospheric carbon fixed by plants and accumulated as biomass. Continuous and accurate measurements of terrestrial NPP at the global scale are possible using satellite data. Since early 2000, for the first time, the MODIS sensors onboard the Terra and Aqua satellites, have operationally provided scientists with near real-time global terrestrial gross primary production (GPP) and net photosynthesis (PsnNet) data. These data are provided at 1 km spatial resolution and an 8-day interval, and annual NPP covers 109,782,756 km2 of vegetated land. These GPP, PsnNet and NPP products are collectively known as MOD17 and are part of a larger suite of MODIS land products (Justice et al. 2002), one of the core Earth System or Climate Data Records (ESDR or CDR).

  6. Laparoscopic adjustable gastric banding. A prospective randomized study comparing the Swedish Adjustable Gastric Band and the MiniMizer Extra: one-year results

    PubMed Central

    Brimas, Gintautas; Strupas, K?stutis

    2011-01-01

    Introduction A number of different adjustable gastric bands are available for laparoscopic adjustable gastric banding (LAGB). Few attempts have been made to compare the influence of band design differences for efficiency and complication rate and conflicting results have emerged from comparative studies. Aim To compare SAGB (Swedish Adjustable Gastric Band) and MiniMizer Extra adjustable gastric bands. Material and methods One hundred and three patients were included in the prospective randomized study. All patients underwent LAGB. The SAGB was used in 49 and MiniMizer Extra in 54 patients. The primary endpoint was weight loss, and secondary endpoints were complication rate, correction of co-morbidities and improvement of quality of life. Results There were no early complications. A significant difference in the proportion of patients who have reached good or excellent weight loss results (? 50% of initial excess body mass index loss) was found in favour of the MiniMizer Extra group (29.6% vs. 8.2%, p = 0.006). No difference was found in other weight loss parameters, resolution of co-morbidities and improvement of quality of life. One oesophageal dilatation and one leakage were diagnosed in the MiniMizer Extra group. Five band penetrations (9.3%) were diagnosed in the MiniMizer Extra group and no penetrations in the SAGB group (p = 0.069). Conclusions No major significant differences were found between the compared bands. Further results need to be confirmed by longer follow-up. PMID:23255982

  7. Extra-intestinal coccidiosis in the kiwi (Apteryx spp.).

    PubMed

    Morgan, Kerri J; Alley, Maurice R; Pomroy, William E; Gartrell, Brett D; Castro, Isabel; Howe, Laryssa

    2013-04-01

    Despite significant conservation intervention, the kiwi (Apteryx spp.) is in serious population decline. To increase survival in the wild, conservation management includes rearing of young birds in captivity, safe from introduced mammalian predators. However, an increase in density of immunologically naïve kiwi increases the risk of exposure to disease, including coccidia. Intestinal coccidiosis has recently been described in the kiwi, and although extra-intestinal coccidiosis was first recognized in kiwi in 1978, very little is known about this disease entity. This study used archived histological tissues and reports from routine necropsies to describe the pathology of naturally occurring extra-intestinal coccidiosis. At least 4.5% of all kiwi necropsied during 1991 to 2011 (n=558) were affected by extra-intestinal coccidiosis, and it is estimated that it caused death in 0.9 to 1.2% of kiwi in the study group. Four forms were recognized: renal, hepatic, and, less commonly, splenic and pulmonary. At necropsy, renal coccidiosis was associated with miliary white streaks and foci through the kidneys, renomegaly, and renal pallor or congestion. Renal meronts and gametocytes were confined to the distal convoluted tubules and collecting ducts, and were associated with renal tubular necrosis and tubular obstruction. Hepatic miliary pinpoint foci were present throughout the hepatic parenchyma associated microscopically with macromeronts measuring 304×227 µm. In two cases, clusters of splenic meronts were identified, and a similar lesion was identified in the pulmonary interstitium of another case. Juvenile, captive kiwi were most often affected with extra-intestinal coccidiosis, illustrating an increased expression of disease with population manipulation for conservation purposes. PMID:23581440

  8. Extra-CNS metastasis from glioblastoma: a rare clinical entity.

    PubMed

    Awan, Musaddiq; Liu, Stanley; Sahgal, Arjun; Das, Sunit; Chao, Samuel T; Chang, Eric L; Knisely, Jonathan P S; Redmond, Kristin; Sohn, Jason W; Machtay, Mitchell; Sloan, Andrew E; Mansur, David B; Rogers, Lisa R; Lo, Simon S

    2015-05-01

    Extra-CNS metastasis from glioblastoma (ECMGBM) is an emerging but little known clinical entity. We review pre-clinical and translational publications assessing the ability of GBM to spread locally and outside the CNS. Reported cases demonstrating ECMGBM are reviewed providing a summary of presentations for the entity. Special attention is placed on transmission of GBM through organ transplantation. Finally, predictions are made as to the future significance of ECMGBM, especially in the context of better outcomes in CNS GBM. PMID:25907706

  9. Extra Corporeal Membrane Oxygenation (ECMO) review of a lifesaving technology

    PubMed Central

    Makdisi, George

    2015-01-01

    Extra Corporeal Membrane Oxygenation (ECMO) indications and usage has strikingly progressed over the last 20 years; it has become essential tool in the care of adults and children with severe cardiac and pulmonary dysfunction refractory to conventional management. In this article we will provide a review of ECMO development, clinical indications, patients management, options and cannulations techniques, complications, outcomes, and the appropriate strategy of organ management while on ECMO. PMID:26380745

  10. Auto-concealment of supersymmetry in extra dimensions

    NASA Astrophysics Data System (ADS)

    Dimopoulos, Savas; Howe, Kiel; March-Russell, John; Scoville, James

    2015-06-01

    In supersymmetric (SUSY) theories with extra dimensions the visible energy in sparticle decays can be significantly reduced and its energy distribution broadened, thus significantly weakening the present collider limits on SUSY. The mechanism applies when the lightest supersymmetric particle (LSP) is a bulk state — e.g. a bulk modulino, axino, or gravitino — the size of the extra dimensions ≳ 10-14 cm, and for a broad variety of visible sparticle spectra. In such cases the lightest ordinary supersymmetric particle (LOSP), necessarily a brane-localised state, decays to the Kaluza-Klein (KK) discretuum of the LSP. This dynamically realises the compression mechanism for hiding SUSY as decays into the more numerous heavier KK LSP states are favored. We find LHC limits on right-handed slepton LOSPs evaporate, while LHC limits on stop LOSPs weaken to ˜ 350 ÷ 410 GeV compared to ˜ 700 GeV for a stop decaying to a massless LSP. Similarly, for the searches we consider, present limits on direct production of degenerate first and second generation squarks drop to ˜ 450 GeV compared to ˜ 800 GeV for a squark decaying to a massless LSP. Auto-concealment typically works for a fundamental gravitational scale of M * ˜ 10 ÷ 100 TeV, a scale sufficiently high that traditional searches for signatures of extra dimensions are mostly avoided. If superpartners are discovered, their prompt, displaced, or stopped decays can also provide new search opportunities for extra dimensions with the potential to reach M * ˜ 109 GeV. This mechanism applies more generally than just SUSY theories, pertaining to any theory where there is a discrete quantum number shared by both brane and bulk sectors.

  11. 17. NBS TOOL ROOM. MISCELLANEOUS TOOLS USED DURING EXTRA VEHICULAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. NBS TOOL ROOM. MISCELLANEOUS TOOLS USED DURING EXTRA VEHICULAR ACTIVITY (EVA) MISSIONS AND NBS TRAINING. FROM LEFT TO RIGHT THE TOOLS ARE: SHUTTLE TRANSPORTATION SYSTEM (STS) PORTABLE FOOT RESTRAINT (PFR), ESSEX WRENCH, SOCKET WRENCH, SAFETY TETHER REEL (LEFT REAR), MINI WORKSTATION (CENTER REAR), TETHERS (FRONT CENTER), HUBBLE SPACE TELESCOPE (HST) POWER TOOL (FRONT RIGHT), HUBBLE SPACE TELESCOPE & PORTABLE FOOT RESTRAINT (REAR RIGHT). - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

  12. The Merits of Giving an Extra Credit Quiz

    ERIC Educational Resources Information Center

    Carroll, Ryall

    2014-01-01

    In the past, Ryall Carroll struggled to get students to arrive on time, read the material in advance of the class, and to start class on topic. In an attempt to address these issues, he started implementing an extra-credit two-question quiz at the beginning of every class, hoping it would provide a small incentive for students to at least come on

  13. Exploring the universal extra dimension at the LHC

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Gautam; Datta, Anindya; Majee, Swarup Kumar; Raychaudhuri, Amitava

    2009-11-01

    Besides supersymmetry, the other prime candidate of physics beyond the Standard Model (SM), crying out for verification at the CERN Large Hadron Collider (LHC), is extra-dimension. To hunt for effects of Kaluza-Klein (KK) excitations of known fermions and bosons is very much in the agenda of the LHC. These KK states arise when the SM particles penetrate in the extra space-like dimension(s). In this paper, we consider a 5d scenario, called 'Universal Extra Dimension', where the extra space coordinate, compactified on an orbifold S/Z, is accessed by all the particles. The KK number ( n) is conserved at all tree level vertices. This entails the production of KK states in pairs and renders the lightest KK particle stable, which leaves the detector carrying away missing energy. The splitting between different KK flavors is controlled by the zero mode masses and the bulk- and brane-induced one-loop radiative corrections. We concentrate on the production of an n=1 KK electroweak gauge boson in association with an n=1 KK quark. This leads to a signal consisting of only one jet, one or more leptons and missing p. For definiteness we usually choose the inverse radius of compactification to be R=500 GeV, which sets the scale of the lowest lying KK states. We show on a case-by-case basis (depending on the number of leptons in the final state) that with 10 fb -1 integrated luminosity at the LHC with √{s}=14 TeV this signal can be detected over the SM background by imposing appropriate kinematic cuts. We record some of the expectations for a possible intermediate LHC run at √{s}=10 TeV and also exhibit the integrated luminosity required to obtain a 5 σ signal as a function of R.

  14. Extra Dimensions in Photon or Jet plus Missing Transverse Energy

    NASA Astrophysics Data System (ADS)

    Cardaci, Marco

    2010-02-01

    Recent studies of the CMS collaboration are presented on the sensitivity to searches for large (ADD) extra dimensions in channels with missing transverse energy (MET), i.e. the channels jets plus MET and photon plus MET. These studies are based on detailed detector simulation, including all Standard Model backgrounds. Particular emphasis is given to possible early discoveries, i.e. with 100 pb-1 or less. Projected 95% CL exclusion limits as function of luminosity are presented as well.

  15. Effect of Extra Dimensions on Gravitational Waves from Cosmic Strings

    SciTech Connect

    O'Callaghan, Eimear; Chadburn, Sarah; Geshnizjani, Ghazal; Gregory, Ruth; Zavala, Ivonne

    2010-08-20

    We show how the motion of cosmic superstrings in extra dimensions can modify the gravitational wave signal from cusps. Additional dimensions both round off cusps, as well as reducing the probability of their formation, and thus give a significant dimension dependent damping of the gravitational waves. We look at the implication of this effect for LIGO and LISA, as well as commenting on more general frequency bands.

  16. Effect of extra dimensions on gravitational waves from cosmic strings.

    PubMed

    O'Callaghan, Eimear; Chadburn, Sarah; Geshnizjani, Ghazal; Gregory, Ruth; Zavala, Ivonne

    2010-08-20

    We show how the motion of cosmic superstrings in extra dimensions can modify the gravitational wave signal from cusps. Additional dimensions both round off cusps, as well as reducing the probability of their formation, and thus give a significant dimension dependent damping of the gravitational waves. We look at the implication of this effect for LIGO and LISA, as well as commenting on more general frequency bands. PMID:20868089

  17. Extra phalangeal crease - A trait in forensic identification.

    PubMed

    Singh, Bahadur; Krishan, Kewal; Kanchan, Tanuj

    2015-10-01

    In the past, many biological, anthropological and forensic studies have been conducted on variations in finger and palm ridge patterns, however, finger crease patterns have not received much attention in the literature. The photocase shows an obvious extra phalangeal crease in the little finger as an extremely rarely reported characteristic. Similar unique characteristics need to be reported for their rarity and significance in forensic investigations. PMID:26344449

  18. Lunar and terrestrial planet formation in the Grand Tack scenario.

    PubMed

    Jacobson, S A; Morbidelli, A

    2014-09-13

    We present conclusions from a large number of N-body simulations of the giant impact phase of terrestrial planet formation. We focus on new results obtained from the recently proposed Grand Tack model, which couples the gas-driven migration of giant planets to the accretion of the terrestrial planets. The giant impact phase follows the oligarchic growth phase, which builds a bi-modal mass distribution within the disc of embryos and planetesimals. By varying the ratio of the total mass in the embryo population to the total mass in the planetesimal population and the mass of the individual embryos, we explore how different disc conditions control the final planets. The total mass ratio of embryos to planetesimals controls the timing of the last giant (Moon-forming) impact and its violence. The initial embryo mass sets the size of the lunar impactor and the growth rate of Mars. After comparing our simulated outcomes with the actual orbits of the terrestrial planets (angular momentum deficit, mass concentration) and taking into account independent geochemical constraints on the mass accreted by the Earth after the Moon-forming event and on the time scale for the growth of Mars, we conclude that the protoplanetary disc at the beginning of the giant impact phase must have had most of its mass in Mars-sized embryos and only a small fraction of the total disc mass in the planetesimal population. From this, we infer that the Moon-forming event occurred between approximately 60 and approximately 130 Myr after the formation of the first solids and was caused most likely by an object with a mass similar to that of Mars. PMID:25114304

  19. Lunar and terrestrial planet formation in the Grand Tack scenario

    PubMed Central

    Jacobson, S. A.; Morbidelli, A.

    2014-01-01

    We present conclusions from a large number of N-body simulations of the giant impact phase of terrestrial planet formation. We focus on new results obtained from the recently proposed Grand Tack model, which couples the gas-driven migration of giant planets to the accretion of the terrestrial planets. The giant impact phase follows the oligarchic growth phase, which builds a bi-modal mass distribution within the disc of embryos and planetesimals. By varying the ratio of the total mass in the embryo population to the total mass in the planetesimal population and the mass of the individual embryos, we explore how different disc conditions control the final planets. The total mass ratio of embryos to planetesimals controls the timing of the last giant (Moon-forming) impact and its violence. The initial embryo mass sets the size of the lunar impactor and the growth rate of Mars. After comparing our simulated outcomes with the actual orbits of the terrestrial planets (angular momentum deficit, mass concentration) and taking into account independent geochemical constraints on the mass accreted by the Earth after the Moon-forming event and on the time scale for the growth of Mars, we conclude that the protoplanetary disc at the beginning of the giant impact phase must have had most of its mass in Mars-sized embryos and only a small fraction of the total disc mass in the planetesimal population. From this, we infer that the Moon-forming event occurred between approximately 60 and approximately 130 Myr after the formation of the first solids and was caused most likely by an object with a mass similar to that of Mars. PMID:25114304

  20. Extra-Neural Metastases of Malignant Gliomas: Myth or Reality?

    PubMed Central

    Beauchesne, Patrick

    2011-01-01

    Malignant gliomas account for approximately 60% of all primary brain tumors in adults. Prognosis for these patients has not significantly changed in recent years despite debulking surgery, radiotherapy and cytotoxic chemotherapywith a median survival of 912 months. Virtually no patients are cured of their illness. Malignant gliomas are usually locally invasive tumors, though extra-neural metastases can sometimes occur late in the course of the disease (median of two years). They generally appear after craniotomy although spontaneous metastases have also been reported. The incidence of these metastases from primary intra-cranial malignant gliomas is low; it is estimated at less than 2% of all cases. Extra-neural metastases from gliomas frequently occur late in the course of the disease (median of two years), and generally appear after craniotomy, but spontaneous metastases have also been reported. Malignant glioma metastases usually involve the regional lymph nodes, lungs and pleural cavity, and occasionally the bone and liver. In this review, we present three cases of extra-neural metastasis of malignant gliomas from our department, summarize the main reported cases in literature, and try to understand the mechanisms underlying these systemic metastases. PMID:24212625

  1. Framework for model independent analyses of multiple extra quark scenarios

    NASA Astrophysics Data System (ADS)

    Barducci, Daniele; Belyaev, Alexander; Buchkremer, Mathieu; Cacciapaglia, Giacomo; Deandrea, Aldo; De Curtis, Stefania; Marrouche, Jad; Moretti, Stefano; Panizzi, Luca

    2014-12-01

    In this paper we present an analysis strategy and a dedicated tool to determine the exclusion confidence level for any scenario involving multiple heavy extra quarks with generic decay channels, as predicted in several extensions of the Standard Model. We have created, validated and used a software package, called XQCAT (eXtra Quark Combined Analysis Tool), which is based on publicly available experimental data from direct searches for top partners and from Supersymmetry inspired searches. By means of this code, we recast the limits from CMS on new heavy extra quarks considering a complete set of decay channels. The resulting exclusion confidence levels are presented for some simple scenarios with multiple states and general coupling assumptions. Highlighting the importance of combining multiple topology searches to obtain accurate re-interpretations of the existing searches, we discuss the reach of the SUSY analyses so as to set bounds on new quark resonances. In particular, we report on the re-interpretation of the existing limits on benchmark scenarios with one and multiple pair-produced top partners having non-exclusive couplings to the third Standard Model generation of quarks.

  2. Extra-team connections for knowledge transfer between staff teams

    PubMed Central

    Ramanadhan, Shoba; Wiecha, Jean L.; Emmons, Karen M.; Gortmaker, Steven L.; Viswanath, Kasisomayajula

    2009-01-01

    As organizations implement novel health promotion programs across multiple sites, they face great challenges related to knowledge management. Staff social networks may be a useful medium for transferring program-related knowledge in multi-site implementation efforts. To study this potential, we focused on the role of extra-team connections (ties between staff members based in different site teams) as potential channels for knowledge sharing. Data come from a cross-sectional study of afterschool childcare staff implementing a health promotion program at 20 urban sites of the Young Men's Christian Association of Greater Boston. We conducted a sociometric social network analysis and attempted a census of 91 program staff members. We surveyed 80 individuals, and included 73 coordinators and general staff, who lead and support implementation, respectively, in this study. A multiple linear regression model demonstrated a positive relationship between extra-team connections (? = 3.41, P < 0.0001) and skill receipt, a measure of knowledge transfer. We also found that intra-team connections (within-team ties between staff members) were also positively related to skill receipt. Connections between teams appear to support knowledge transfer in this network, but likely require greater active facilitation, perhaps via organizational changes. Further research on extra-team connections and knowledge transfer in low-resource, high turnover environments is needed. PMID:19528313

  3. Inflation with an extra light scalar field after Planck

    NASA Astrophysics Data System (ADS)

    Vennin, Vincent; Koyama, Kazuya; Wands, David

    2016-03-01

    Bayesian inference techniques are used to investigate situations where an additional light scalar field is present during inflation and reheating. This includes (but is not limited to) curvaton-type models. We design a numerical pipeline where simeq 200 inflaton setups × 10 reheating scenarios = 2000 models are implemented and we present the results for a few prototypical potentials. We find that single-field models are remarkably robust under the introduction of light scalar degrees of freedom. Models that are ruled out at the single-field level are not improved in general, because good values of the spectral index and the tensor-to-scalar ratio can only be obtained for very fine-tuned values of the extra field parameters and/or when large non-Gaussianities are produced. The only exception is quartic large-field inflation, so that the best models after Planck are of two kinds: plateau potentials, regardless of whether an extra field is added or not, and quartic large-field inflation with an extra light scalar field, in some specific reheating scenarios. Using Bayesian complexity, we also find that more parameters are constrained for the models we study than for their single-field versions. This is because the added parameters not only contribute to the reheating kinematics but also to the cosmological perturbations themselves, to which the added field contributes. The interplay between these two effects lead to a suppression of degeneracies that is responsible for having more constrained parameters.

  4. Signatures from an extra-dimensional seesaw model

    SciTech Connect

    Blennow, Mattias; Melbeus, Henrik; Ohlsson, Tommy; Zhang He

    2010-08-15

    We study the generation of small neutrino masses in an extra-dimensional model, where singlet fermions are allowed to propagate in the extra dimension, while the standard model particles are confined to a brane. Motivated by the fact that extra-dimensional models are nonrenormalizable, we truncate the Kaluza-Klein towers at a maximal Kaluza-Klein number. This truncation, together with the structure of the bulk Majorana mass term, motivated by the Sherk-Schwarz mechanism, implies that the Kaluza-Klein modes of the singlet fermions pair to form Dirac fermions, except for a number of unpaired Majorana fermions at the top of each tower. These heavy Majorana fermions are the only sources of lepton number breaking in the model, and similarly to the type-I seesaw mechanism, they naturally generate small masses for the left-handed neutrinos. The lower Kaluza-Klein modes mix with the light neutrinos, and the mixing effects are not suppressed with respect to the light-neutrino masses. Compared to conventional fermionic seesaw models, such mixing can be more significant. We study the signals of this model at the Large Hadron Collider, and find that the current low-energy bounds on the nonunitarity of the leptonic mixing matrix are strong enough to exclude an observation.

  5. An Extra Push from Entrance-Channel Effects

    SciTech Connect

    Grar, Nabila; Rowley, Neil

    2006-08-14

    The fusion probability for heavy symmetric systems is known to show certain very specific features. Apart from the large variance of the fusion barrier distribution, it is found that the energy at which the s-wave transmission is 0.5 is shifted to an energy significantly higher than the nominal (e.g. Bass) Coulomb barrier. This last feature is referred to in the literature as the 'extra push' effect. Many models have been devised to explain the origin of these findings. It is worth noting, however, that despite the extra push, the capture cross section is still greatly enhanced at the very lowest energies. This fact cannot be explained within the framework of macroscopic theories involving conditional saddle points or frictional forces. We have performed full coupled-channel calculations for heavy, symmetric systems treating correctly the long-range Coulomb excitations of the collective quadrupole- and octupole-phonon states in the target and projectile. The results obtained show that the extra push and the overall shape of the fusion probability are simply explained by these entrance-channel effects.

  6. Ovulation and extra-ovarian origin of ovarian cancer.

    PubMed

    Yang-Hartwich, Yang; Gurrea-Soteras, Marta; Sumi, Natalia; Joo, Won Duk; Holmberg, Jennie C; Craveiro, Vinicius; Alvero, Ayesha B; Mor, Gil

    2014-01-01

    The mortality rate of ovarian cancer remains high due to late diagnosis and recurrence. A fundamental step toward improving detection and treatment of this lethal disease is to understand its origin. A growing number of studies have revealed that ovarian cancer can develop from multiple extra-ovarian origins, including fallopian tube, gastrointestinal tract, cervix and endometriosis. However, the mechanism leading to their ovarian localization is not understood. We utilized in vitro, ex vivo, and in vivo models to recapitulate the process of extra-ovarian malignant cells migrating to the ovaries and forming tumors. We provided experimental evidence to support that ovulation, by disrupting the ovarian surface epithelium and releasing chemokines/cytokines, promotes the migration and adhesion of malignant cells to the ovary. We identified the granulosa cell-secreted SDF-1 as a main chemoattractant that recruits malignant cells towards the ovary. Our findings revealed a potential molecular mechanism of how the extra-ovarian cells can be attracted by the ovary, migrate to and form tumors in the ovary. Our data also supports the association between increased ovulation and the risk of ovarian cancer. Understanding this association will lead us to the development of more specific markers for early detection and better prevention strategies. PMID:25135607

  7. Planetary Protection: Two Relevant Terrestrial Examples

    NASA Astrophysics Data System (ADS)

    Chyba, C.

    2002-09-01

    Concerns about potential pathogens in returned samples from Mars ("Mars Sample Return: Issues and Recommendations", National Research Council, 1997) or planetary satellites ("Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies", National Research Council, 1998) focus on two potential types of pathogenesis, toxic and infectious. The National Research Council reports cited above state that the chances of extraterrestrial organisms proving either toxic or infectious to humans are extremely low, but cannot be entirely ruled out. Here I discuss recently discovered terrestrial examples relevant to each possibility, in order to make these concerns concrete. The first example concerns the production of hepatotoxins (toxins affecting the liver) and neurotoxins by cyanobacteria in glacial lakes on alpine pastures in Switzerland. In this example, mat-forming benthic cyanobacteria are implicated in a hundred cattle poisonings that have been reported from alpine pasteurs in southeastern Switzerland over the past twenty-five years (e.g. K. Mez et al, Hydrobiologia 368, 1-15 (1998)). It is unlikely that these cyanobacteria evolved the toxins in response to dairy cows; rather the susceptibility of cattle to these toxins seems simply to be an unfortunate coincidence of a toxin working across a large evolutionary distance. The second example concerns the recent demonstration that the decimation of shallow-water Caribbean elkhorn coral is due to infection by a common fecal enterobacterium associated with the human gut (K. L. Patterson et al., PNAS 99, 8725-8730 (2002)). The bacterium, Serratia marcenscens, is also a free-living microbe in water and soil, as well as an opportunistic pathogen in a variety of animal species. The distance between humans and corals emphasizes the possibility that certain organisms may prove pathogenic across a wide evolutionary divide. Of course, in neither of these cases are the evolutionary distances crossed as large as those that would likely exist between any martian organisms and human beings. The possibility that life on the two worlds might share a common ancestor suggests that these distances may not be altogether incomparable, but this remains speculation pending further exploration. This work is supported in part by the NASA Exobiology Program and a Presidential Early Career Award for Scientists and Engineers.

  8. 7 CFR 51.560 - U.S. Extra No. 1.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Celery Grades 51.560 U.S. Extra No. 1. U.S. Extra No. 1 consists of stalks of celery of similar varietal characteristics which are well...

  9. 7 CFR 51.560 - U.S. Extra No. 1.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Celery Grades 51.560 U.S. Extra No. 1. U.S. Extra No. 1 consists of stalks of celery of similar varietal characteristics which are well...

  10. The coevolution of circumperineal color and terrestriality.

    PubMed

    Pampush, James D; Cramer, Jennifer D

    2015-05-01

    Old World monkeys (Cercopithecoidea) are unusual among primates for the high percentage of species exhibiting circumperineal coloration, as well as the large percentage of highly terrestrial species. Kingdon [1974, 1980] suggested that circumperineal skin coloration is functionally related to terrestriality, but this hypothesis has not been tested. From the literature, we collected data on habitat use (terrestrial/arboreal) and circumperineal coloration (present/absent) for 78 species. Indeed, among the 78 species surveyed here, 75% of them fall into either the category of colored circumperineals with terrestrial lifestyle, or of uncolored circumperineals with arboreal lifestyle (Χ(2)(1) = 19.550, P < 0.001). However, conventional statistical procedures assume all taxa are equally related-which is not usually the case in multispecies analyses-leading to higher rates of both type I and II statistical errors. We performed Bayesian trait coevolution analyses that show that models of dependent trait evolution are not significantly better than models assuming independent evolution of the two traits (log-likelihood ratio test P = 0.396, Bayes Factor = 1). Bayesian nodal reconstructions of the cercopithecoid phylogeny indicate that relatively few trait transitions are needed to account for the distributions of the two traits. Further, chi-squared distributional tests show that sub-family affiliation (i.e., Cercopithecinae, Colobinae) is an accurate predictor of trait status. The discordance of the analyses may represent the results of a few different evolutionary scenarios, but ultimately circumperineal coloration seems weakly linked to terrestrial ecology. PMID:25612177

  11. Supporting tools of solar-terrestrial science

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Solar-terrestrial science is pursued by individuals and teams of workers situated in academia, research institutes, industry, and government laboratories. Progress in the field is made in various ways, but publication of results in scientific journals is the principal means of assuring that the knowledge gained from research is available to the public, now and in the future. In general, much of the research in the field is made via careful evaluation of data viewed in the context of fundamental physical principles as set forth in theoretical and analytical models, and computer simulations of physical processes. In addition, there is accumulation of knowledge expressed in the development of empirical or phenomenological models. Experience gained over the past three decades of solar-terrestrial research indicated that advances in the field require a diversity of resources and that the health of the entire discipline depends upon a balance among these. To maintain the health of the discipline, NASA and other federal funding agencies concerned with solar-terrestrial research must work together to insure that the following resources are available in reasonable measure to support solar-terrestrial research endeavors: ground-based facilities; balloons and rockets; spaceborne experiments; information networks; computational resources; models of solar terrestrial processes; data bases and archives; and research students.

  12. Supporting tools of solar-terrestrial science

    NASA Astrophysics Data System (ADS)

    1989-09-01

    Solar-terrestrial science is pursued by individuals and teams of workers situated in academia, research institutes, industry, and government laboratories. Progress in the field is made in various ways, but publication of results in scientific journals is the principal means of assuring that the knowledge gained from research is available to the public, now and in the future. In general, much of the research in the field is made via careful evaluation of data viewed in the context of fundamental physical principles as set forth in theoretical and analytical models, and computer simulations of physical processes. In addition, there is accumulation of knowledge expressed in the development of empirical or phenomenological models. Experience gained over the past three decades of solar-terrestrial research indicated that advances in the field require a diversity of resources and that the health of the entire discipline depends upon a balance among these. To maintain the health of the discipline, NASA and other federal funding agencies concerned with solar-terrestrial research must work together to insure that the following resources are available in reasonable measure to support solar-terrestrial research endeavors: ground-based facilities; balloons and rockets; spaceborne experiments; information networks; computational resources; models of solar terrestrial processes; data bases and archives; and research students.

  13. Terrestrial Planet Formation Around Close Binary Stars

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Quintana, Elisa V.

    2003-01-01

    Most stars reside in multiple star systems; however, virtually all models of planetary growth have assumed an isolated single star. Numerical simulations of the collapse of molecular cloud cores to form binary stars suggest that disks will form within such systems. Observations indirectly suggest disk material around one or both components within young binary star systems. If planets form at the right places within such circumstellar disks, they can remain in stable orbits within the binary star systems for eons. We are simulating the late stages of growth of terrestrial planets around close binary stars, using a new, ultrafast, symplectic integrator that we have developed for this purpose. The sum of the masses of the two stars is one solar mass, and the initial disk of planetary embryos is the same as that used for simulating the late stages of terrestrial planet growth within our Solar System and in the Alpha Centauri wide binary star system. Giant planets &are included in the simulations, as they are in most simulations of the late stages of terrestrial planet accumulation in our Solar System. When the stars travel on a circular orbit with semimajor axis of up to 0.1 AU about their mutual center of mass, the planetary embryos grow into a system of terrestrial planets that is statistically identical to those formed about single stars, but a larger semimajor axis and/or a significantly eccentric binary orbit can lead to significantly more dynamically hot terrestrial planet systems.

  14. DNA Barcoding Reveals Cryptic Diversity in Lumbricus terrestris L., 1758 (Clitellata): Resurrection of L. herculeus (Savigny, 1826)

    PubMed Central

    James, Samuel W.; Porco, David; Decaëns, Thibaud; Richard, Benoit; Rougerie, Rodolphe; Erséus, Christer

    2010-01-01

    The widely studied and invasive earthworm, Lumbricus terrestris L., 1758 has been the subject of nomenclatural debate for many years. However these disputes were not based on suspicions of heterogeneity, but rather on the descriptions and nomenclatural acts associated with the species name. Large numbers of DNA barcode sequences of the cytochrome oxidase I obtained for nominal L. terrestris and six congeneric species reveal that there are two distinct lineages within nominal L. terrestris. One of those lineages contains the Swedish population from which the name-bearing specimen of L. terrestris was obtained. The other contains the population from which the syntype series of Enterion herculeum Savigny, 1826 was collected. In both cases modern and old representatives yielded barcode sequences allowing us to clearly establish that these are two distinct species, as different from one another as any other pair of congeners in our data set. The two are morphologically indistinguishable, except by overlapping size-related characters. We have designated a new neotype for L. terrestris. The newly designated neotype and a syntype of L. herculeus yielded DNA adequate for sequencing part of the cytochrome oxidase I gene (COI). The sequence data make possible the objective determination of the identities of earthworms morphologically identical to L. terrestris and L. herculeus, regardless of body size and segment number. Past work on nominal L. terrestris could have been on either or both species, although L. herculeus has yet to be found outside of Europe. PMID:21206917

  15. Bog bodies.

    PubMed

    Lynnerup, Niels

    2015-06-01

    In northern Europe during the Iron Age, many corpses were deposited in bogs. The cold, wet and anaerobic environment leads in many cases to the preservation of soft tissues, so that the bodies, when found and excavated several thousand years later, are remarkably intact. Since the 19th century the bog bodies have been studied using medical and natural scientific methods, and recently many bog bodies have been re-examined using especially modern, medical imaging techniques. Because of the preservation of soft tissue, especially the skin, it has been possible to determine lesions and trauma. Conversely, the preservation of bones is less good, as the mineral component has been leached out by the acidic bog. Together with water-logging of collagenous tissue, this means that if the bog body is simply left to dry out when found, as was the case pre-19th century, the bones may literally warp and shrink, leading to potential pitfalls in paleopathological diagnostics. Bog bodies have in several instances been crucial in determining the last meal, as gut contents may be preserved, and thus augment our knowledge on pre-historic diet by adding to, for example, stable isotope analyses. This article presents an overview of our knowledge about the taphomic processes as well as the methods used in bog body research. PMID:25998635

  16. [Cryptococcus where they are not expected: Five case reports of extra-cerebral and extra-pulmonary cryptococcosis].

    PubMed

    Cazorla, Arnault; Alanio, Alexandre; Bretagne, Stphane; Polivka, Marc; Shaar-Chneker, Caroline; Kaci, Rachid; Brouland, Jean-Philippe; Chrtien, Fabrice; Jouvion, Grgory

    2015-12-01

    Cryptococcosis is a serious infection, possibly lethal, of worldwide distribution. It mainly affects immunosuppressed patients resulting with pulmonary and/or meningeal involvements or disseminated infections. Due to the rarity of visceral and osseous infections, and to the absence of specific clinical symptoms, this diagnosis is often deferred. Resulting of diagnostic errors, samples are often directed to the department of pathology and more rarely to the department of mycology. Histopathological examination appears crucial, highlighting encapsulated yeasts with alcian blue staining. Once the diagnosis is performed, an appropriate antifungal therapy must be quickly introduced because these infections are associated with a high mortality rate. The aim of our work was to report five extra-cerebral and extra-pulmonary cryptococcosis cases, to describe their histopathological features, to evoke diagnostic techniques and to discuss the differential diagnoses. PMID:26596691

  17. Atmospheric Escape from Solar System Terrestrial Planets and Exoplanets

    NASA Astrophysics Data System (ADS)

    Tian, Feng

    2015-05-01

    It has been known for decades that atmospheric escape is important for the evolution of terrestrial planets in the Solar System, although exactly how atmospheric escape changes the atmospheres of these bodies is still hotly debated. Rapidly increasing numbers of exoplanet observations provide new targets against which atmospheric escape models are tested. In this review we summarize recent studies related to atmospheric escape from exoplanets. The most important conclusions are that (a) escape can significantly influence the volatile contents of low-mass exoplanets (with mass lower than those of Uranus and Neptune) and the atmosphere and climate evolution histories of Solar System terrestrial planets; (b) models including detailed physics and chemistry in planetary upper atmospheres will be important for the interpretation of existing and future observations of exoplanets; and (c) fluid models considering 2D or 3D planetary upper atmospheres and particle models for planetary exospheres will be important not only for comparisons with observations but also for order of magnitude estimates of atmospheric escape rates. Our understanding of how escape shapes planetary atmospheres and influences the climate of low-mass planets can be expected to advance substantially in the coming decade.

  18. Primary, large extra-axial chordoma in proximal tibia: a rare case report with literature review and diagnostic implications.

    PubMed

    Rekhi, Bharat

    2016-03-01

    Primary extra-axial chordomas have been rarely documented, especially in the appendicular bones. Until now, nine such cases, objectively confirmed with positive brachyury immunostaining, have been reported. A 42-year-old male presented with pain in his right tibial tuberosity (shin) of 2-3 years duration without any associated swelling. He denied complaints related to any other lesion elsewhere in his body. Plain radiograph of his lower limbs revealed a large, eccentric, well-defined, lytic lesion containing internal septae with a narrow zone of transition and a sclerotic medullary border in the upper metaphysis of his right tibia, associated with a pathological fracture. There was no other lesion identified in his spine on radiographic imaging. Biopsy sections revealed a tumour composed of polygonal cells with moderate to abundant eosinophilic to vacuolated/'bubbly' cytoplasm (physaliphorous cells) arranged in lobules within a conspicuous myxoid matrix. By immunohistochemistry, tumour cells were diffusely positive for pan cytokeratin (AE1/AE3), epithelial membrane antigen (EMA), CK19, S100P, meso (HBME1) and Brachyury/T. Diagnosis of an a primary extra-axial chordoma was finally rendered. Subsequently, the patient underwent bone grafting from his iliac crest. The present case constitutes as the 11th documented case of an extra-axial, intraosseous chordoma and the 10th such case occurring in the appendicular bones. Literature review of similar cases; their diagnostic mimics along with diagnostic and therapeutic implications of such cases are discussed herewith. PMID:26522887

  19. Re-Conceptualizing Extra Help for High School Students in a High Standards Era.

    ERIC Educational Resources Information Center

    Balfanz, Robert; McPartland, James; Shaw, Alta

    The push for higher academic standards has resulted in an increase in the numbers of high school students needing extra help. The need for extra help is most pervasive in high-poverty areas and most high school students need extra help not in traditional basic elementary skills but in reading, mathematics, and advanced reasoning skills. Most

  20. 46 CFR 9.1 - Extra compensation; Coast Guard civilian personnel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Extra compensation; Coast Guard civilian personnel. 9.1 Section 9.1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC EXTRA COMPENSATION FOR OVERTIME SERVICES § 9.1 Extra compensation; Coast Guard civilian...

  1. 46 CFR 9.1 - Extra compensation; Coast Guard civilian personnel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Extra compensation; Coast Guard civilian personnel. 9.1 Section 9.1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC EXTRA COMPENSATION FOR OVERTIME SERVICES § 9.1 Extra compensation; Coast Guard civilian...

  2. 46 CFR 9.1 - Extra compensation; Coast Guard civilian personnel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Extra compensation; Coast Guard civilian personnel. 9.1 Section 9.1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC EXTRA COMPENSATION FOR OVERTIME SERVICES § 9.1 Extra compensation; Coast Guard civilian...

  3. 46 CFR 9.1 - Extra compensation; Coast Guard civilian personnel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Extra compensation; Coast Guard civilian personnel. 9.1 Section 9.1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC EXTRA COMPENSATION FOR OVERTIME SERVICES § 9.1 Extra compensation; Coast Guard civilian...

  4. 46 CFR 9.1 - Extra compensation; Coast Guard civilian personnel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Extra compensation; Coast Guard civilian personnel. 9.1 Section 9.1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC EXTRA COMPENSATION FOR OVERTIME SERVICES § 9.1 Extra compensation; Coast Guard civilian...

  5. Terrestrialization, Miniaturization and Rates of Diversification in African Puddle Frogs (Anura: Phrynobatrachidae)

    PubMed Central

    Zimkus, Breda M.; Lawson, Lucinda; Loader, Simon P.; Hanken, James

    2012-01-01

    Terrestrialization, the evolution of non-aquatic oviposition, and miniaturization, the evolution of tiny adult body size, are recurring trends in amphibian evolution, but the relationships among the traits that characterize these phenomena are not well understood. Furthermore, these traits have been identified as possible “key innovations” that are predicted to increase rates of speciation in those lineages in which they evolve. We examine terrestrialization and miniaturization in sub-Saharan puddle frogs (Phrynobatrachidae) in a phylogenetic context to investigate the relationship between adaptation and diversification through time. We use relative dating techniques to ascertain if character trait shifts are associated with increased diversification rates, and we evaluate the likelihood that a single temporal event can explain the evolution of those traits. Results indicate alternate reproductive modes evolved independently in Phrynobatrachus at least seven times, including terrestrial deposition of eggs and terrestrial, non-feeding larvae. These shifts towards alternate reproductive modes are not linked to a common temporal event. Contrary to the “key innovations” hypothesis, clades that exhibit alternate reproductive modes have lower diversification rates than those that deposit eggs aquatically. Adult habitat, pedal webbing and body size have no effect on diversification rates. Though these traits putatively identified as key innovations for Phrynobatrachus do not seem to be associated with increased speciation rates, they may still provide opportunities to extend into new niches, thus increasing overall diversity. PMID:22509392

  6. Comparative planetology: Significance for terrestrial geology

    NASA Technical Reports Server (NTRS)

    Frey, H. V.; Lowman, P. D., R.

    1978-01-01

    The crustal evolution of the terrestrial planets increase in complexity and duration with increasing size and mass of the planet. The lunar and mercurian surfaces are largely the result of intense, post-differentiation impact bombardment and subsequent volcanic filling of major impact basins. Mars, being larger, has evolved further: crustal uplifts, rifting, and shield volcanoes have begun to modify its largely Moon-like surface. The Earth is the large end-number of this sequence, where modern plate tectonic processes have erased the earlier lunar and martian type of surfaces. Fundamental problems of the origin of terrestrial continents, ocean basins, and plate tectonics are now addressed within the context of the evolutionary pattern of the terrestrial planets.

  7. Increased extra-pair paternity in broods of aging males and enhanced recruitment of extra-pair young in a migratory bird.

    PubMed

    Bowers, E Keith; Forsman, Anna M; Masters, Brian S; Johnson, Bonnie G P; Johnson, L Scott; Sakaluk, Scott K; Thompson, Charles F

    2015-09-01

    Despite keen interest in extra-pair mating in birds, its adaptive significance remains unresolved. Here, we use a multi-year dataset to test whether traits of a female's social mate influence her propensity to produce extra-pair offspring in a population of house wrens, and whether producing extra-pair young has consequences for a female's fitness through effects on offspring survival. Females were most likely to produce extra-pair offspring when paired with old males and when paired with males on poor-quality territories, although this latter effect was marginally nonsignificant. Among offspring, the cutaneous immunity of within-pair young decreased as the age of their sires increased, but cutaneous immunity of extra-pair young was not affected by the age of their extra-pair sires or by the age of the males rearing them. Extra-pair offspring were more likely than within-pair offspring to return as breeding adults to the local population, with extra-pair sons being more likely to return as a breeder for multiple years. Our findings support the hypothesis that females produce extra-pair offspring to enhance their inclusive fitness beyond what they are capable of given the male with which they are socially paired. PMID:26258950

  8. Increased extra-pair paternity in broods of aging males and enhanced recruitment of extra-pair young in a migratory bird

    PubMed Central

    Bowers, E. Keith; Forsman, Anna M.; Masters, Brian S.; Johnson, Bonnie G. P.; Johnson, L. Scott; Sakaluk, Scott K.; Thompson, Charles F.

    2015-01-01

    Despite keen interest in extra-pair mating in birds, its adaptive significance remains unresolved. Here, we use a multi-year dataset to test whether traits of a female’s social mate influence her propensity to produce extra-pair offspring in a population of house wrens, and whether producing extra-pair young has consequences for a female’s fitness through effects on offspring survival. Females were most likely to produce extra-pair offspring when paired with old males and when paired with males on poor-quality territories, although this latter effect was marginally non-significant. Among offspring, the cutaneous immunity of within-pair young decreased as the age of their sires increased, but cutaneous immunity of extra-pair young was not affected by the age of their extra-pair sires or by the age of the males rearing them. Extra-pair offspring were more likely than within-pair offspring to return as breeding adults to the local population, with extra-pair sons being more likely to return as a breeder for multiple years. Our findings support the hypothesis that females produce extra-pair offspring to enhance their inclusive fitness beyond what they are capable of given the male with which they are socially paired. PMID:26258950

  9. Some effects of pollutants in terrestrial ecosystems

    USGS Publications Warehouse

    Stickel, W.H.

    1975-01-01

    Summary: Pollutants tend to simplify plant and animal communities by causing a progressive loss of species. At the extreme, this leads to erosion and loss of soil fertility. Weedy, broadly adapted species increase. Among animals, carnivorous species and groups are often the first to suffer. This is partly because of their exposure at the top of the food chain, and partly, it appears, because of physiological differences. Species differences in susceptibility are abundant and are often critical. One result is that when one pest is controlled another is likely to flare up. Resistance appears commonly in insects and is known in other fast-breeding forms, including fishes, frogs, and rodents. Resistant individuals can carry toxicant loads that make them dangerous food for other animals. Some groups, including mollusks and annelids, are naturally resistant to many organohalogens and tend to accumulate them. Animals such as birds may carry lipophilic pollutants in large amounts with apparent safety until forced to draw upon their fat. They may then suffer delayed mortality, and no doubt suffer reproductive or behavioral effects at sublethal levels. Lipophilic pollutants in the brain rise when body lipids decrease and fall when body lipids increase. Mutagenesis can be caused by some common pollutants and the mutagenic properties of most chemicals are far too little known. Fortunately, common pesticides are not likely to be strong mutagens. Mutagenicity may be affecting certain long-lived and slow-breeding species in the wild, but most species have enough population turnover to swamp an occasional mutagenic event. Behavioral changes can be caused by relatively low levels of contaminants, but it is often hard to demonstrate them without using high dosages. Reproduction may or may not be affected adversely by low exposures. At certain exposures that are below the toxic levels of a chemical, a biostimulatory effect is to be expected. Food chain accumulations definitely do occur when persistent chemicals enter organisms that eliminate them poorly. However, loss of chemicals in the food chain must be more common than accumulation. The great concentration from water to aquatic organism is chiefly a physical phenomenon, not a food chain effect, but it affords high starting levels for these chains. Terrestrial food chains often start at a high level with heavily contaminated, struggling prey. Litter feeders are another important base. Vegetation may be contaminated enough to be dangerous to animals that eat it. Dermal and respiratory routes of intoxication occur in the wild, but the oral route is far more important at most times and places. The organisms that govern soil fertility and texture are affected more by cultivation than by pesticides. Above ground, growing knowledge of resistance, species differences, and biological controls is leading to integrated control, in which use of chemicals is limited and specific. We do not know what is happening to most nontarget invertebrates. Amphibians and reptiles may be killed by applications of insecticides, but are not highly sensitive and can carry large residues. Effects of these residues on reproduction are little known. Heavy kills of birds by pesticides still occur in the field. Fish-eating and bird-eating birds also undergo shell thinning and related reproductive troubles in many areas, sometimes to the point of population decline and local or regional extermination. DDE most often correlates with shell thinning in the wild and in experiments. No other known chemical approaches DDE in causing severe and lasting shell thinning. Herbivorous birds seem to be largely immune to this effect. It is uncertain how much dieldrin and PCBs contribute to embryotoxicity in carnivorous birds. Mammals may be killed by the more toxic pesticides, but some of the commonest small rodents are so resistant, and lose their residues so rapidly, that they are of little

  10. Terrestrial impact melt rocks and glasses

    NASA Astrophysics Data System (ADS)

    Dressler, B. O.; Reimold, W. U.

    2001-12-01

    The effects of meteorite and comet impact on Earth are rock brecciation, the formation of shock metamorphic features, rock melting, and the formation of impact structures, i.e. simple craters, complex craters, and multi-ring basins. Large events, such as the 65-Ma Chicxulub impact, are believed to have had catastrophic environmental effects that profoundly influenced the development of life on Earth. In this review, an attempt is made to summarize some of the voluminous literature on impact melting, one important aspect of planetary impact, provide some comments on this process, and to make suggestions for future research. The products of impact melting are glasses, impact melt rocks, and pseudotachylites. Our treatise deals mainly with the geological setting, petrography, and major-element chemistry of melt rocks and glasses. Impact glasses, in several petrographic aspects, are similar to volcanic glasses, but they are associated with shock metamorphosed mineral and rock fragments and, in places, with siderophile element anomalies suggestive of meteoritic contamination. They are found in allogenic breccia deposits within (fall-back 'suevite') and outside (fall-out 'suevite') impact craters and, as spherules, in distal ejecta. Large events, such as the K/T boundary Chicxulub impact, are responsible for the formation of worldwide ejecta horizons which are associated with siderophile element anomalies and shock metamorphosed mineral and rock debris. Impact glasses have a bulk chemical composition that is homogeneous but exemptions to this rule are common. On a microscopic scale, however, impact glasses are commonly strikingly heterogeneous. Tektites are glasses ejected from craters over large distances. They are characterized by very low water and volatile contents and element abundances and ratios that are evidence that tektites formed by melting of upper crustal, sedimentary rocks. Four tektite strewn-fields are known, three of which can be tied to specific impact craters. Impact melt rocks form sheets, lenses, and dike-like bodies within or beneath allogenic fallback breccia deposits in the impact crater and possibly on crater terraces and flanks. Dikes of impact melt rocks also intrude the rocks of the crater floor. They commonly contain shock metamorphosed target rock and mineral fragments in various stages of assimilation and are glassy or fine- to coarse-grained. Chemically, they are strikingly homogeneous, but as with impact glasses, exemptions to this rule do exist. Large and thick melt bodies, such as the Sudbury Igneous Complex (SIC), are differentiated or may represent a combination of impact melt rocks sensu-strictu and impact-triggered, deep-crustal melts. A concerted, multidisciplinary approach to future research on impact melting and on other aspects of meteorite and comet impact is advocated. Impact models are models only and uncritical reliance on their validity will not lead to a better understanding of impact processes—especially of melting, excavation, and deposition of allogenic breccias and the spatial position of breccias in relation to sheets and lenses of melt rocks within the crater. Impact-triggered pressure-release melting of target rocks beneath the excavation cavity may be responsible for the existence of melt rocks beneath the impact melt rocks sensu-strictu. This controversial idea needs to be tested by a re-evaluation of existing data and models, be they based on field or laboratory research. Only a relatively small number of terrestrial impact structures has been investigated in sufficient detail as it relates to geological and geophysical mapping. In this review, we summarize observations made on impact melt rocks and impact glasses in a number of North American (Brent, Haughton, Manicouagan, New Quebec, Sudbury, Wanapitei, all in Canada), Asian (Popigai, Russia; Zhamanshin, Kazakhstan), two South African structures (Morokweng and Vredefort), the Henbury crater field of Australia, and one European crater (Ries, Germany). Our tables listing major-element chemical compositions of impact glasses and melt rocks, however, include also data from structures not dealt with in further detail.

  11. Debris from terrestrial planet formation: the Moon-forming collision

    NASA Astrophysics Data System (ADS)

    Jackson, Alan P.; Wyatt, Mark C.

    2012-09-01

    We study the evolution of debris created in the giant impacts expected during the final stages of terrestrial planet formation. The starting point is the debris created in a simulation of the Moon-forming impact. The dynamical evolution is followed for 10 Myr including the effects of Earth, Venus, Mars and Jupiter. The spatial distribution evolves from a clump in the first few months to an asymmetric ring for the first 10 kyr and finally becoming an axisymmetric ring by about 1 Myr after the impact. By 10 Myr after the impact 20 per cent of the particles have been accreted on to Earth and 17 per cent on to Venus, with 8 per cent ejected by Jupiter and other bodies playing minor roles. However, the fate of the debris also depends strongly on how fast it is collisionally depleted, which depends on the poorly constrained size distribution of the impact debris. Assuming that the debris is made up of 30 per cent by mass mm-cm-sized vapour condensates and 70 per cent boulders up to 500 km, we find that the condensates deplete rapidly on 1000 yr time-scales, whereas the boulders deplete predominantly dynamically. By considering the luminosity of dust produced in collisions within the boulder-debris distribution we find that the Moon-forming impact would have been readily detectable around other stars in Spitzer 24 ?m surveys for around 25 Myr after the impact, with levels of emission comparable to many known hot dust systems. The vapour condensates meanwhile produce a short-lived, optically thick, spike of emission. We use these surveys to make an estimate of the fraction of stars that form terrestrial planets, FTPF. Since current terrestrial planet formation models invoke multiple giant impacts, the low fraction of 10-100 Myr stars found to have warm (>rsim150 K) dust implies that FTPF?10 per cent. For this number to be higher, it would require that either terrestrial planets are largely fully formed when the protoplanetary disc disperses, or that impact generated debris consists purely of sub-km objects such that its signature is short-lived.

  12. Were early pterosaurs inept terrestrial locomotors?

    PubMed Central

    2015-01-01

    Pterodactyloid pterosaurs are widely interpreted as terrestrially competent, erect-limbed quadrupeds, but the terrestrial capabilities of non-pterodactyloids are largely thought to have been poor. This is commonly justified by the absence of a non-pterodactyloid footprint record, suggestions that the expansive uropatagia common to early pterosaurs would restrict hindlimb motion in walking or running, and the presence of sprawling forelimbs in some species. Here, these arguments are re-visited and mostly found problematic. Restriction of limb mobility is not a problem faced by extant animals with extensive fight membranes, including species which routinely utilise terrestrial locomotion. The absence of non-pterodactyloid footprints is not necessarily tied to functional or biomechanical constraints. As with other fully terrestrial clades with poor ichnological records, biases in behaviour, preservation, sampling and interpretation likely contribute to the deficit of early pterosaur ichnites. Suggestions that non-pterodactyloids have slender, mechanically weak limbs are demonstrably countered by the proportionally long and robust limbs of many Triassic and Jurassic species. Novel assessments of pterosaur forelimb anatomies conflict with notions that all non-pterodactyloids were obligated to sprawling forelimb postures. Sprawling forelimbs seem appropriate for species with ventrally-restricted glenoid articulations (seemingly occurring in rhamphorhynchines and campylognathoidids). However, some early pterosaurs, such as Dimorphodon macronyx and wukongopterids, have glenoid arthrologies which are not ventrally restricted, and their distal humeri resemble those of pterodactyloids. It seems fully erect forelimb stances were possible in these pterosaurs, and may be probable given proposed correlation between pterodactyloid-like distal humeral morphology and forces incurred through erect forelimb postures. Further indications of terrestrial habits include antungual sesamoids, which occur in the manus and pes anatomy of many early pterosaur species, and only occur elsewhere in terrestrial reptiles, possibly developing through frequent interactions of large claws with firm substrates. It is argued that characteristics possibly associated with terrestriality are deeply nested within Pterosauria and not restricted to Pterodactyloidea as previously thought, and that pterodactyloid-like levels of terrestrial competency may have been possible in at least some early pterosaurs. PMID:26157605

  13. Solar-Terrestrial Science Strategy Workshop

    NASA Technical Reports Server (NTRS)

    Banks, Peter M. (Editor); Roberts, William T. (Editor); Kropp, Jack (Editor)

    1989-01-01

    The conclusions and recommendations reached at the Solar Terrestrial Science Strategy Workshop are summarized. The charter given to this diverse group was: (1) to establish the level of scientific understanding to be accomplished with the completion of the current and near term worldwide programs; (2) identify the significant scientific questions to be answered by future solar terrestrial programs, and the programs required to answer these questions; and (3) map out a program strategy, taking into consideration currently perceived space capabilities and constraints, to accomplish the identified program.

  14. Solar and Terrestrial Neutrino Results from Borexino

    NASA Astrophysics Data System (ADS)

    Calaprice, Frank; Borexino Collaboration

    2012-08-01

    Borexino is a low background liquid scintillation detector currently acquiring solar and terrestrial neutrino data at the LNGS underground laboratory in Italy. In the three years since the start of operations in 2007, Borexino has produced measurements of 7Be and 8B solar neutrinos, as well as measurements of terrestrial and long-baseline reactor anti-neutrinos. The measurements of sub-MeV neutrinos were possible owing to a breakthrough in low background methods. Current results and prospects for future measurements with lower background and higher accuracy are discussed in the context of exploring the transition from vacuum to matter enhanced neutrino oscillations.

  15. Why Plants Were Terrestrial from the Beginning.

    PubMed

    Harholt, Jesper; Moestrup, Øjvind; Ulvskov, Peter

    2016-02-01

    The current hypothesis is that land plants originated from a charophycean green alga and that a prominent feature for adaptation to land was their development of alternating life cycles. Our work on cell wall evolution and morphological and physiological observations in the charophycean green algae challenged us to reassess how land plants became terrestrial. Our hypothesis is simple in that the charophycean green algae ancestors were already living on land and had been doing so for some time before the emergence of land plants. The evolution of alternate life cycles merely made the ancestral land plants evolutionary successful and had nothing to do with terrestrialization per se. PMID:26706443

  16. Tectonic Evolution of the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    Solomon, Sean C.; Senski, David G. (Technical Monitor)

    2002-01-01

    The NASA Planetary Geology and Geophysics Program supported a wide range of work on the geophysical evolution of the terrestrial planets during the period 1 April 1997 - 30 September 2001. We here provide highlights of the research carried out under this grant over the final year of the award, and we include a full listing of publications and scientific meeting presentations supported by this project. Throughout the grant period, our group consisted of the Principal Investigator and several Postdoctoral Associates, all at the Department of Terrestrial Magnetism (DTM) of the Carnegie Institution of Washington.

  17. Auroral Spectra as a Tool for Detecting Extra-Etrrestrial Life

    NASA Astrophysics Data System (ADS)

    Akasofu, S.; Lummerzheim, D.; Frey, H. U.

    2001-12-01

    One of the most prominent emissions from the aurora is the greenish-white light from oxygen atoms, while the Jovian aurora contains atomic hydrogen emissions. The oxygen emission, the so-called "green line" (557.7 nm), of the terrestrial aurora, arises mostly from the fact that plants release abundant free oxygen into the atmosphere by the photosynthesis process. Thus, the green line shows that plant life exists on Earth. It was recently reported that Upsilon Andromedae, has three planets. This star is a solar-type star. This discovery and many others in recent years are significant because they show the planetary system, like the solar system, is not quite unique. It is expected that a number of stars are accompanied by several planets, and it may not be too long before the aurora on such planets can be discovered. One possible way to detect plant life on such planets is to examine their auroral emissions. If the strong line emission at 557.7 nm and other UV/EUV emissions from oxygen can be detected among other emissions in the planetary aurora, the possibility of the presence of plant life is high. Further, if plant life exists, animal life, whether lower or higher, can also exist there. The Earth-like auroral processes leading to the oxygen emissions require, in addition to plant life, both stellar wind and planetary magnetism. It is highly probable that solar-type stars have stellar wind. If such a planet does not have a strong dipole-like magnetic field, the stellar wind can cause atmospheric glow in which the oxygen emissions may be present. In any case, if the oxygen emissions are detected in the planetary auroral spectra, the possibility of plant life there is high. The dissociation of CO2 can also release oxygen. However, if the condition of the planets is similar to that of the Earth, its contribution is very small. It is expected that auroral science will evolve in a variety of ways in the future. It is suggested that the subject dealt with here is such an example. It is hoped that auroral science could contribute to search for extra-terrestrial life, one of the ultimate human endeavors.

  18. The young adult hip: extra-articular causes of hip pain and how to pick the winners

    PubMed Central

    Bray, Edward D. R.; Sherafati, Milad; Cutts, Charlotte L.

    2015-01-01

    Hip pain in young adults is not always caused by intra-articular pathology, even in the presence of abnormal examination and imaging findings. Therefore, management of young adult hip pain requires processes that identify patients who are likely to benefit from surgical intervention. An important investigation in the diagnostic pathway is the intra-articular injection; a negative response to this should alert the surgeon to the presence of symptomatic extra-articular causes of hip pain. Our aim was to identify the proportion of patients referred with intra-articular pathology whose primary cause of pain was of extra-articular origin. A total of 143 intra-articular hip injections (local anaesthetic + corticosteroid) were performed over a 2-year period. Mean patient age was 41.95 (95% confidence interval: 39.50–44.41) years with a mean body mass index of 27 (95% confidence interval: 25.77–28.23); 26% of patients (n = 37) had no relief of symptoms after intra-articular injection. Of the patients with no relief, 81.1% (n = 30) were found to have extra-articular pathology as the cause of their pain and the remainder are under on-going investigation. Intra-articular hip injection is an important investigation in the diagnostic pathway of young adult hip pain, as it can highlight and differentiate those patients with referred pain from extra-articular pathology. This benefit may be further enhanced if injections are performed in theatres using image intensifier, under sedation, as it allows direct penetration into the joint without any local anaesthetic infiltration of surrounding tissue. The latter allows immediate objective assessment of symptom relief, eliminating the need to rely on retrospective patient recall of symptom change. PMID:27011814

  19. Body Imaging

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images.

  20. Body Imaging

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images. In this photograph, a patient undergoes an open MRI.

  1. Evolution of the structure of iron meteorites under terrestrial climate

    NASA Astrophysics Data System (ADS)

    Yakovlev, G.; Grokhovsky, V.

    2014-07-01

    Introduction: Meteoritic iron is affected by many factors in terrestrial conditions. First of all, abundance of water induces an oxidization process. Despite rather high nickel concentration in meteoritic iron, rust is forming on a surface of extraterrestrial matter. But also transformation processes occur inside meteorites at rather low climatic temperatures (0.15 of the melting temperature). Such reaction has been observed for the first time in the Bilibino meteorite [1]. Experiments: Structural changes in kamacite were investigated in ancient iron meteorite falls (Aliskerovo IIIAB, Bilibino IIAB). All of them demonstrate uncompleted recrystallization. Polished sections were analyzed using inverted optical microscope Axiovert 40 MAT and SEM SIGMA VP with EDS and EBSD units. Results: Different percentage of recrystallization was found in Aliskerovo and Bilibino meteorites. 4 % of the section surface in Aliskerovo is occupied by recrystallization products. This value for Bilibino is equal to 80 %. It was noticed that recrystallization started from the kamacite-rhabdite boundaries in the Bilibino meteorite and from the kamacite-schreibersite boundaries in the Aliskerovo meteorite. There are strongly-etched sites in the recrystallized zones. One can suggest that these sites are traces of former boundaries. It is possible to think that the boundaries were moving with jumps because of the position of these sites in the recrystallized zone. Also it was noticed that there is a net of cracks before the recrystallization reaction front. A possible reason for this phenomenon is a wedge of extra material which generates an elastic stress field in the vicinity of the grain boundary [2]. All these phenomena can be explained using the Kirkendall effect on the grain boundary: the boundary shift is the result of the different concentrations of vacancies between the boundary sides.

  2. Three Extra Mirror or Sequential Families: Case for a Heavy Higgs Boson and Inert Doublet

    SciTech Connect

    Martinez, Homero; Melfo, Alejandra; Nesti, Fabrizio; Senjanovic, Goran

    2011-05-13

    We study the possibility of the existence of extra fermion families and an extra Higgs doublet. We find that requiring the extra Higgs doublet to be inert leaves space for three extra families, allowing for mirror fermion families and a dark matter candidate at the same time. The emerging scenario is very predictive: It consists of a standard model Higgs boson, with a mass above 400 GeV, heavy new quarks between 340 and 500 GeV, light extra neutral leptons, and an inert scalar with a mass below M{sub Z}.

  3. Body Imaging

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Magnetic Resonance Imaging (MRI) and Computer-aided Tomography (CT) images are often complementary. In most cases, MRI is good for viewing soft tissue but not bone, while CT images are good for bone but not always good for soft tissue discrimination. Physicians and engineers in the Department of Radiology at the University of Michigan Hospitals are developing a technique for combining the best features of MRI and CT scans to increase the accuracy of discriminating one type of body tissue from another. One of their research tools is a computer program called HICAP. The program can be used to distinguish between healthy and diseased tissue in body images.

  4. Body parts

    NASA Astrophysics Data System (ADS)

    Ayiter, Elif

    2010-01-01

    In this project, the artist wishes to examine corporeality in the virtual realm, through the usage of the (non)-physical body of the avatar. An art installation created in the virtual world of Second Life, which is meant to be accessed with site specific avatars, will provide the creative platform whereby this investigation is undertaken. Thus, "body parts" seeks to challenge the residents of virtual environments into connecting with the virtual manifestations, i.e., avatars of others in an emotionally expressive/intimate manner.

  5. Extra-Articular Ganglion Cysts around the Knee Joint

    PubMed Central

    Park, Sang-Eun; Panchal, Karnav; Kim, Young-Yul; Ji, Jong-Hun; Park, Sung-Ryeoll; Park, Min-Kyu

    2015-01-01

    Purpose The purpose of this study was to report clinical results of open excision of extra-articular ganglion cysts around the knee joint combined with arthroscopic management of intra-articular pathologies if present. Materials and Methods Of the total 107 cases of cystic lesions around the knee, 23 cases of extra-articular ganglion cysts were reviewed between January 2006 and July 2011. There were 13 males and 10 females with a mean age of 48 years (range, 30 to 73 years). The mean follow-up duration was 40 months (range, 30 to 60 months). Preoperative magnetic resonance imaging (MRI) scan was done in all cases. Open surgical excision of the cyst was performed after arthroscopic management of intra-articular pathologies in all but 1 case. At the last follow-up, Lysholm and International Knee Documentation Committee (IKDC) scores were evaluated and MRI was conducted to detect recurrence. Results The mean Lysholm and IKDC scores showed significant improvement (p=0.005 and 0.013, respectively).The location of the cysts was anterior in 9, lateral in 7, medial in 6, and posterosuperior in 1. Intra-articular pathologies were found in 16/23 cases (69.6%). In 10/23 cases (43%), the cyst was connected to the knee joint. Three months postoperative MRI did not show any recurrence of ganglion cysts except for 1 case. Conclusions In the treatment of extra-articular ganglion cysts, MRI can be useful for detecting intra-articular lesions and connecting orifices, and arthroscopic management of intra-articular pathologies with open excision of the cyst should be considered as a viable treatment option. PMID:26672721

  6. Proposal for periodic verifications of electromedical devices integrated to terrestrial Technical Ambulance Inspection (TAI)

    NASA Astrophysics Data System (ADS)

    Del Aguila Heidenreich, R.; Vanella, O.; Bruni, R.; Taborda, R.

    2011-12-01

    In Argentina, electromedical devices may only be commercialized if they meet safety and performance requirements established by current regulations, ensuring their safety and intended performance when leaving the Factory. However, during usage, natural wearing and overloading may change this condition, especially if used in extra hospital services performed by ambulances, which are likely to be subjected to rough handling conditions and hitting. This proposal explains the chosen methodology to address the periodic verification activities of electro medical devices within the process of terrestrial Technical Ambulance Inspection (TAI). Among the results stand out the set of methods for verification and the lists used to record the outcome of this evaluation. Outstanding conclusions include that the operations meet the conditions of an analogous mechanism to that of a Technical Vehicle Inspection (existing for other vehicles), and that the same working structure can be used as a basis for making a manual of procedures for a TAI.

  7. Dynamically Downscaling Precipitation from Extra-Tropical Cyclones

    NASA Astrophysics Data System (ADS)

    Champion, A.; Hodges, K.; Bengtsson, L.

    2012-04-01

    Recent flooding events experienced by the UK and Western Europe have highlighted the potential disruption caused by precipitation associated with extra-tropical cyclones. The question as to the effect of a warming climate on these events also needs to be addressed to determine whether such events will become more frequent or more intense in the future. The changes in precipitation can be addressed through the use of Global Climate Models (GCMs), however the resolution of GCMs are often too coarse to drive hydrological models, required to investigate any flooding that may be associated with the precipitation. The changes to the precipitation associated with extra-tropical cyclones are investigated by tracking cyclones in two resolutions of the ECHAM5 GCM, T213 and T319 for 20th and 21st century climate simulations. It is shown that the intensity of extreme precipitation associated with extra-tropical cyclones is predicted to increase in a warmer climate at both resolutions. It was also found that the increase in resolution shows an increase in the number of extreme events for several fields, including precipitation; however it is also seen that the magnitude of the response is not uniform across the seasons. The tails of the distributions are investigated using Extreme Value Theory (EVT) using a Generalised Pareto Distribution (GPD) with a Peaks over Threshold (POT) method, calculating return periods for given return levels. From the cyclones identified in the T213 resolution of the GCM a small number of cyclones were selected that pass over the UK, travelling from the South-West to the North-East. These are cyclones that are more likely to have large amounts of moisture associated with them and therefore potentially being associated with large precipitation intensities. Four cyclones from each climate were then selected to drive a Limited Area Model (LAM), to gain a more realistic representation of the precipitation associated with each extra-tropical cyclone. The suitability of the LAM for downscaling was evaluated by running the LAM for the events of June and July 2007 (UK floods) and comparing the output to observations. The results from this comparison provide confidence that the model is able of reproducing realistic intensities for extreme precipitation events. Whilst this method does not allow for a robust comparison between the climates it does for allow for an analysis of the method, and whether dynamically downscaling individual events is suitable. It was found that by nesting the LAM within the GCM, large increases in the precipitation intensities were seen, as well as gaining a greater temporal resolution. Analysis of more events will allow a more robust comparison between climates.

  8. Effective description of brane terms in extra dimensions

    SciTech Connect

    del Aguila, Francisco; Perez-Victoria, Manuel; Santiago, Jose; /Fermilab

    2006-01-01

    We study how theories defined in (extra-dimensional) spaces with localized defects can be described perturbatively by effective field theories in which the width of the defects vanishes. These effective theories must incorporate a ''classical'' renormalization, and we propose a renormalization prescription a la dimensional regularization for codimension 1, which can be easily used in phenomenological applications. As a check of the validity of this setting, we compare some general predictions of the renormalized effective theory with those obtained in a particular ultraviolet completion based on deconstruction.

  9. Inert scalar dark matter in an extra dimension inspired model

    SciTech Connect

    Lineros, R.A.; Santos, F.A. Pereira dos E-mail: fabio.alex@fis.puc-rio.br

    2014-10-01

    In this paper we analyze a dark matter model inspired by theories with extra dimensions. The dark matter candidate corresponds to the first KaluzaKlein mode of an real scalar added to the Standard Model. The tower of new particles enriches the calculation of the relic abundance. For large mass splitting, the model converges to the predictions of the inert singlet dark matter model. For nearly degenerate mass spectrum, coannihilations increase the cross-sections used for direct and indirect dark matter searches. Moreover, the KaluzaKlein zero mode can mix with the SM higgs and further constraints can be applied.

  10. Radion stabilization from the vacuum on flat extra dimensions

    SciTech Connect

    Santos, Eli; Perez-Lorenzana, A.; Pimentel, Luis O.

    2008-01-15

    Volume stabilization in models with flat extra dimensions could follow from vacuum energy residing in the bulk when translational invariance is spontaneously broken. We study a simple toy model that exemplifies this mechanism which considers a massive scalar field with nontrivial boundary conditions at the end points of the compact space, and includes contributions from brane and bulk cosmological constants. We perform our analysis in the conformal frame where the radion field, associated with volume variations, is defined, and present a general strategy for building stabilization potentials out of those ingredients. We also provide working examples for the interval and the T{sup n}/Z{sub 2} orbifold configuration.

  11. Left ventricular thrombus associated with arteriovenous extra corporeal membrane oxygenation

    PubMed Central

    Makdisi, George; Hashmi, Zubair A.; Wozniak, Thomas C.

    2015-01-01

    Extra corporeal membrane oxygenation (ECMO) has remarkably progressed over the recent years. It has become an invaluable tool in the care of adults and pediatric patients with severe cardiogenic shock. At the initiation of ECMO support, the left ventricular contractility is profoundly impaired. Inadequate right ventricular drainage and bronchial circulation can lead to left ventricular distension, with potential deleterious consequences, ranging from inadequate myocardial rest, pulmonary edema, or intracardiac clot formation. Therefore, it is of extreme importance to ensure an adequate left ventricular drainage. Here we present a case of LV thrombus developed while the patient is on central venoarterial (VA) ECMO. PMID:26716054

  12. Applying EFT to Higgs pair production in universal extra dimensions

    NASA Astrophysics Data System (ADS)

    Edelhäuser, Lisa; Knochel, Alexander; Steeger, Thomas

    2015-11-01

    We investigate single Higgs and Higgs pair production at the LHC in models of Universal Extra Dimensions. After calculating the relevant cross sections, we use the UED model as a testing ground for the Effective Field Theory approach to physics beyond the Standard Model. We show how the UED contributions to Higgs production can be matched to a dimension-6 operator. We then discuss the range of validity of this approach, in particular for Higgs pair production, and determine the sensitivity to the number of KK modes in the loop.

  13. Search for universal extra dimensions in ppbar collisions

    SciTech Connect

    Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Alexeev, Guennadi D.; Alkhazov, Georgiy D.; Alton, Andrew K.; Alverson, George O.; Aoki, Masato; Askew, Andrew Warren; /Florida State U. /Stockholm U.

    2011-12-01

    We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb{sup -1}, collected by the D0 detector at a p{bar p} center of mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R{sup -1} > 260 GeV in a minimal UED model.

  14. Leprechaunism with mosaicism 46, XX/47, XX extra ring chromosome.

    PubMed Central

    Ventruto, V; Sebastio, L; Sebastio, G; DeMasi, R V; Vota, U; Farina, L; Festa, B

    1977-01-01

    A case of leprechaunism with a chromosomal abnormality is reported. The patient was a female infant, born to healthy, consanguineous young parents. Her course was one of extreme marasmus, with death at 3 months of age. She presented the classical features of the syndrome and chromosome mosaicism 46, XX/47, XX, +r(?). It was not possible to identify the origin of the extra ring chromosome. It is difficult to establish the role of such a cytogenetic finding in the aetiology of the syndrome. Images PMID:592357

  15. Zero point energy on extra dimensions: Noncommutative torus

    SciTech Connect

    Fabi, S.; Harms, B.; Karatheodoris, G.

    2007-09-15

    In this paper we calculate the zero point energy density experienced by observers on M{sup 4} due to a massless scalar field defined throughout M{sup 4}xT{sub F}{sup 2}, where T{sub F}{sup 2} are fuzzy extra dimensions. Using the Green's function approach we calculate the energy density for the commutative torus and the fuzzy torus. We also calculate the energy density for the fuzzy torus using the Hamiltonian approach. Agreement is shown between the Green's function and Hamiltonian approaches.

  16. Detecting Extra Dimension by Helium-Like Ions

    NASA Astrophysics Data System (ADS)

    Liu, Yu-Xiao; Zhang, Xin-Hui; Duan, Yi-Shi

    Considering that gravitational force might deviate from Newton's inverse-square law and become much stronger in small scale, we present a method to detect the possible existence of extra dimensions in the ADD model. By making use of an effective variational wave function, we obtain the nonrelativistic ground energy of a helium atom and its isoelectronic sequence. Based on these results, we calculate gravity correction of the ADD model. Our calculation may provide a rough estimation about the magnitude of the corresponding frequencies which could be measured in later experiments.

  17. APOLLO 9: Dave scott performs Extra Vehicular Activities

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Dave Scott performs Extra Vehicular Activities around the Command Module 'Gumdrop'. From the film documentary 'APOLLO 9: The Duet of Spider & Gumdrop': part of a documentary series made in the early 70's on the APOLLO missions, and narrated by Burgess Meredith. (Actual date created is not known at this time) Mission: APOLLO 9: Earth orbital flight with James A. McDivitt, David R. Scott, and Russell Schweickart. First flight of the Lunar Module. Performed rendezvous, docking and E.V.A..Mission Duration 241hrs 0m 54s.

  18. Charged seven-dimensional spacetimes with spherically symmetric extra dimensions

    SciTech Connect

    De Felice, Antonio; Ringeval, Christophe

    2009-06-15

    We derive exact solutions of the seven-dimensional Einstein-Maxwell equations for a spacetime exhibiting Poincare invariance along four dimensions and spherical symmetry in the extra dimensions. Such topology generically arises in the context of braneworld models. Our solutions generalize previous results on Ricci-flat spacetimes admitting the two-sphere and are shown to include wormhole configurations. A regular coordinate system suitable to describe the whole spacetime is singled out, and we discuss the physical relevance of the derived solutions.

  19. Left ventricular thrombus associated with arteriovenous extra corporeal membrane oxygenation.

    PubMed

    Makdisi, George; Hashmi, Zubair A; Wozniak, Thomas C; Wang, I-Wen

    2015-11-01

    Extra corporeal membrane oxygenation (ECMO) has remarkably progressed over the recent years. It has become an invaluable tool in the care of adults and pediatric patients with severe cardiogenic shock. At the initiation of ECMO support, the left ventricular contractility is profoundly impaired. Inadequate right ventricular drainage and bronchial circulation can lead to left ventricular distension, with potential deleterious consequences, ranging from inadequate myocardial rest, pulmonary edema, or intracardiac clot formation. Therefore, it is of extreme importance to ensure an adequate left ventricular drainage. Here we present a case of LV thrombus developed while the patient is on central venoarterial (VA) ECMO. PMID:26716054

  20. Global calibration of terrestrial reference cells and errors involved in using different irradiance monitoring techniques

    NASA Technical Reports Server (NTRS)

    Curtis, H. B.

    1980-01-01

    The feasibility of global calibration of terrestrial reference cells is discussed. A simple, accurate 'secondary' calibration technique based on ratios of test to reference cell currents measured in natural sunlight is described. Different techniques for monitoring incident irradiance during solar cell performance measurements are also examined and assessed, including the techniques of black-body detectors, calibrated reference cells, and the convolution of spectral response with solar irradiance.