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Sample records for extra terrestrial bodies

  1. 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

  2. Energy use, entropy and extra-terrestrial civilizations

    NASA Astrophysics Data System (ADS)

    Hetesi, Zsolt

    2010-03-01

    The possible number of extra-terrestrial civilizations is estimated by the Drake-equation. Many articles pointed out that there are missing factors and over-estimations in the original equation. In this article we will point out that assuming some axioms there might be several limits for a technical civilization. The key role of the energy use and the problem of the centres and periphery strongly influence the value of the Llifetime of a civilization. Our development have several edifications of the investigations of the growth of an alien civilization.

  3. 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.

  4. 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.

  5. 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.

  6. 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

    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.

  7. 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.

  8. 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.

  9. Beyond Earth: How extra-terrestrial volcanism stretches our definition of a volcano

    NASA Astrophysics Data System (ADS)

    Lopes, R.

    2007-05-01

    Volcanism is a fundamental geologic process that has affected every solid body in the solar system and, presumably, in other solar systems as well. As we explore other worlds, we come across signs of active and past volcanism, some in unexpected places. Volcanism in extraterrestrial worlds can be much different from the examples we see on Earth, but the similarities are also striking. Understanding the eruption mechanisms on other planets is important for better constraining how eruptions behave on Earth under present and past conditions. The discovery of numerous extra-terrestrial volcanoes, including active ones, has stretched our traditional definition of what is a volcano. Prior to the Voyager 1 and 2 spacecraft observations during the late 1970s and early 1980s, the Earth was the only planet known to have active volcanism. When Voyager 1 found active volcanism on Jupiter's moon Io, our understanding of active volcanism, and what causes it, dramatically changed. Io's volcanism is driven by tidal dissipation, fundamentally different from what causes volcanism on Earth. To date, no planet outside the Earth shows evidence of plate tectonics. Despite these differences, the eruption styles and products on other planets show great similarity to Earth's. Voyager went on to observe geysers on Neptune's moon Triton, showing the first evidence of cryovolcanism, a process that has no terrestrial analogue but which appears to be widespread in the outer solar system. The Galileo spacecraft showed that relatively recent cryovolcanic activity may have occurred on Europa and Ganymede. In the last few years, the Cassini spacecraft showed dramatic active plumes on Saturn's moon Enceladus. Features thought to be volcanic have been shown to exist on Titan's very young surface, raising the possibility that active or recently active cryovolcanism may have been present there. As we continue our exploration of the solar system, we need to redefine the fundamental geologic processes

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

    PubMed

    Almár, Iván; 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 δ 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 δ 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.

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

    PubMed

    Almár, Iván; 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 δ 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 δ 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

  12. Extra-terrestrial igneous granites and related rocks: A review of their occurrence and petrogenesis

    NASA Astrophysics Data System (ADS)

    Bonin, Bernard

    2012-11-01

    vast majority of granitic materials recognised so far in the extra-terrestrial record are characterised by ferroan A-type compositions, characterised by high to very high K2O and medium CaO contents, sodic varieties being exceedingly rare. Textural evidence of graphic quartz-alkali feldspar intergrowths within crystallised products suggests that they are igneous in origin and crystallised quickly from a liquid. In water-depleted to water-free environments, fluorine and chlorine can play significant roles, as their effects on liquidus temperatures and crystallising assemblages are nearly identical to those of water. The distribution of alkalis and alkaline earths cannot be related only to extensive crystal fractionation, but is likely induced by supplementary silicate liquid immiscibility. Medium-temperature silicate liquid immiscibility is well known as a mode of differentiation in experimental petrology studies at very low pressures on systems dominated by Fe, Ti, K, and P as major elements. The ultimate question is, therefore, not whether granite (s.l.) occurs in any given planetary body, but if sufficient volumes of granitic materials could have been produced to constitute stable continental nuclei.

  13. 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.

  14. 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.

  15. 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

  16. 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?

  17. 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

  18. 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 μm 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.

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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

  5. Chemical heterogeneities in the interior of terrestrial bodies

    NASA Astrophysics Data System (ADS)

    Plesa, Ana-Catalina; Maurice, Maxime; Tosi, Nicola; Breuer, Doris

    2016-04-01

    Mantle chemical heterogeneities that can strongly influence the interior dynamics have been inferred for all terrestrial bodies of the Solar System and range from local to global scale. Seismic data for the Earth, differences in surface mineral compositions observed in data sets from space missions, and isotopic variations identified in laboratory analyses of meteorites or samples indicate chemically heterogeneous systems. One way to generate large scale geochemical heterogeneities is through the fractional crystallization of a liquid magma ocean. The large amount of energy available in the early stages of planetary evolution can cause melting of a significant part or perhaps even the entire mantle of a terrestrial body resulting in a liquid magma ocean. Assuming fractional crystallization, magma ocean solidification proceeds from the core-mantle boundary to the surface where dense cumulates tend to form due to iron enrichment in the evolving liquid. This process leads to a gravitationally unstable mantle, which is prone to overturn. Following cumulate overturn, a stable stratification may be reached that prevents efficient material transport. As a consequence, mantle reservoirs may be kept separate, possibly for the entire thermo-chemical evolution of a terrestrial body. Scenarios assuming fractional crystallization of a liquid magma ocean have been suggested to explain lavas with distinct composition on Mercury's surface [1], the generation of the Moon's mare basalts by sampling a reservoir consisting of overturned ilmenite-bearing cumulates [2], and the preservation of Mars' geochemical reservoirs as inferred by isotopic analysis of the SNC meteorites [3]. However, recent studies have shown that the style of the overturn as well as the subsequent density stratification are of extreme importance for the subsequent thermo-chemical evolution of a planetary body and may have a major impact on the later surface tectonics and volcanic history. The rapid formation of a

  6. 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

  7. 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.

  8. 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.

  9. Earthsickness: circumnavigation and the terrestrial human body, 1520-1800.

    PubMed

    Chaplin, Joyce E

    2012-01-01

    From their distinctive experience of going around the world, maritime circumnavigators concluded that their characteristic disease, sea scurvy, must result from their being away from land too long, much longer than any other sailors. They offered their scorbutic bodies as proof that humans were terrestrial creatures, physically suited to the earthly parts of a terraqueous globe. That arresting claim is at odds with the current literature on the cultural implications of European expansion, which has emphasized early modern colonists' and travelers' fear of alien places, and has concluded that they had a small and restricted geographic imagination that fell short of the planetary consciousness associated with the nineteenth and twentieth centuries. But circumnavigators did conceive of themselves as actors on a planetary scale, as creatures adapted to all of the land on Earth, not just their places of origin.

  10. Estimating terrestrial amphibian pesticide body burden through dermal exposure.

    PubMed

    Van Meter, Robin J; Glinski, Donna A; Hong, Tao; Cyterski, Mike; Henderson, W Matthew; Purucker, S Thomas

    2014-10-01

    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 ingredients through contact with contaminated soil: imidacloprid (logKow = 0.57), atrazine (logKow = 2.5), triadimefon (logKow = 3.0), fipronil (logKow = 4.11) or pendimethalin (logKow = 5.18). All amphibians had measurable body burdens at the end of the exposure in concentrations ranging from 0.019 to 14.562 μg/g across the pesticides tested. Atrazine produced the greatest body burdens and bioconcentration factors, but fipronil was more permeable to amphibian skin when application rate was considered. Soil partition coefficient and water solubility were much better predictors of pesticide body burden, bioconcentration factor, and skin permeability than logKow. Dermal uptake data can be used to improve risk estimates of pesticide exposure among amphibians as non-target organisms.

  11. Estimation of Fe3+/Fetot. ratio in natural silicate glasses and analogues for extra-terrestrial basalt using Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Di Genova, D.; Hess, K. U.; Chevrel, M. O.; Dingwell, D. B.

    2015-12-01

    The effect of iron oxidation state (Fe3+/Fetot.) on the Raman spectra of pantelleritic (from Pantelleria island) and basaltic glasses (from Etna) and synthetic analogues for extra-terrestrial basaltic glasses (iron-rich martian basalt analogues; Chevrel et al. 2014) has been investigated. The Raman spectra of pantellerite glasses show dramatic changes in the high wavelength region of the spectrum (800-1200cm-1) as iron oxidation state changes. In particular the 970 cm-1 band intensity increases with increasing oxidation state of the glass (Fe3+/Fetot. ratio from 0.24 to 0.83). In contrast, Raman spectra of the basaltic glasses (natural and synthetic) do not show the same oxidation state sensitivity as the pantelleritic samples (Fe3+/Fetot. ratio from 0.15 to 0.79). A shift, however, of the 950 cm-1 band to high wavenumber with decreasing iron oxidation state can be observed. To help develop Raman spectroscopy as a quantitative tool in both geosciences and planetary science we present here an empirical, compositionally-independent model, based on an ideal mixing equation applied to the acquired Raman spectra. This model yields estimates of the iron oxidation state of anhydrous and hydrous silicate glasses of basaltic and pantelleritic composition for Fe3+/Fetot. ranging between 0.15 and 0.83 and water contents up to 2.4 wt.%. The model has been validated using independently characterized natural and synthetic silicate glasses (both anhydrous and hydrous) with a FeO content varying from ~8 to ~22 wt%. The results of this study contribute to increase the compositionally-dependent database previously presented by Di Genova et al. (2015) for Raman spectra of complex silicate glasses. The applications of this model range from microanalysis of silicate glasses (e.g. melt inclusions) to handheld in situ terrestrial field studies and under extreme conditions (e.g. extraterrestrial, volcanic and submarine environments).

  12. 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...

  13. Studies on different geophysical and extra-terrestrial events within the Earth-ionosphere cavity in terms of ULF/ELF/VLF radio waves

    NASA Astrophysics Data System (ADS)

    Sanfui, Minu; Haldar, D. K.; Biswas, Debasish

    2016-10-01

    The space between the two spherical conducting shells, Earth surface and the lower boundary of the ionosphere, behaves as a spherical cavity in which some electromagnetic signals can propagate a long distance and is called Earth-ionosphere waveguide. Through this waveguide ultra low frequency (ULF), extremely low frequency (ELF) and very low frequency (VLF) signals can propagate efficiently with low attenuation. Resonances which occur for ELF waves due to round-the-world propagation interfering with 2n π phase difference are called Schumann resonances. Lightnings are the main sources of energy continuously producing these electromagnetic radiations from the troposphere. Some fixed frequency signals are also transmitted through the waveguide from different stations for navigation purposes. The intensity and phase of these signals at a particular position depend on the waveguide characteristics which are highly influenced by different natural events. Thus the signatures of different geophysical and extra-terrestrial events may be investigated by studying these signals through proper monitoring of the time series data using suitable techniques. In this article, we provide a review on ULF, ELF and VLF signals within the waveguide in terms of different geophysical and extra-terrestrial events like lightning, earthquakes, Leonid meteor shower, solar flares, solar eclipse, geomagnetic storms, and TLEs etc.

  14. 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

  15. Warming-induced reductions in body size are greater in aquatic than terrestrial species

    PubMed Central

    Forster, Jack; Hirst, Andrew G.; Atkinson, David

    2012-01-01

    Most ectothermic organisms mature at smaller body sizes when reared in warmer conditions. This phenotypically plastic response, known as the “temperature-size rule” (TSR), is one of the most taxonomically widespread patterns in biology. However, the TSR remains a longstanding life-history puzzle for which no dominant driver has been found. We propose that oxygen supply plays a central role in explaining the magnitude of ectothermic temperature-size responses. Given the much lower oxygen availability and greater effort required to increase uptake in water vs. air, we predict that the TSR in aquatic organisms, especially larger species with lower surface area–body mass ratios, will be stronger than in terrestrial organisms. We performed a meta-analysis of 1,890 body mass responses to temperature in controlled experiments on 169 terrestrial, freshwater, and marine species. This reveals that the strength of the temperature-size response is greater in aquatic than terrestrial species. In animal species of ∼100 mg dry mass, the temperature-size response of aquatic organisms is 10 times greater than in terrestrial organisms (−5.0% °C−1 vs. −0.5% °C−1). Moreover, although the size response of small (<0.1 mg dry mass) aquatic and terrestrial species is similar, increases in species size cause the response to become increasingly negative in aquatic species, as predicted, but on average less negative in terrestrial species. These results support oxygen as a major driver of temperature-size responses in aquatic organisms. Further, the environment-dependent differences parallel latitudinal body size clines, and will influence predicted impacts of climate warming on food production, community structure, and food-web dynamics. PMID:23129645

  16. Is sexual body shape dimorphism consistent in aquatic and terrestrial chelonians?

    PubMed

    Bonnet, Xavier; Delmas, Virginie; El-Mouden, Hassan; Slimani, Tahar; Sterijovski, Bogoljub; Kuchling, Gerald

    2010-08-01

    Comparisons between aquatic and terrestrial species provide an opportunity to examine how sex-specific adaptations interact with the environment to influence body shape. In terrestrial female tortoises, selection for fecundity favors the development of a large internal abdominal cavity to accommodate the clutch; in conspecific males, sexual selection favors mobility with large openings in the shell. To examine to what extent such trends apply in aquatic chelonians we compared the body shape of males and females of two aquatic turtles (Chelodina colliei and Mauremys leprosa). In both species, females were larger than males. When controlled for body size, females exhibited a greater relative internal volume and a higher body condition index than males; both traits potentially correlate positively with fecundity. Males were more streamlined (hydrodynamic), and exhibited larger openings in the shell providing more space to move their longer limbs; such traits probably improve mobility and copulation ability (the males chase and grab the female for copulation). Overall, although the specific constraints imposed by terrestrial and aquatic locomotion shape the morphology of chelonians differently (aquatic turtles were flatter, hence more hydrodynamic than terrestrial tortoises), the direction for sexual shape dimorphism remained unaffected. Our main conclusion is that the direction of sexual shape dimorphism is probably more consistent than sexual size dimorphism in the animal kingdom.

  17. Is sexual body shape dimorphism consistent in aquatic and terrestrial chelonians?

    PubMed

    Bonnet, Xavier; Delmas, Virginie; El-Mouden, Hassan; Slimani, Tahar; Sterijovski, Bogoljub; Kuchling, Gerald

    2010-08-01

    Comparisons between aquatic and terrestrial species provide an opportunity to examine how sex-specific adaptations interact with the environment to influence body shape. In terrestrial female tortoises, selection for fecundity favors the development of a large internal abdominal cavity to accommodate the clutch; in conspecific males, sexual selection favors mobility with large openings in the shell. To examine to what extent such trends apply in aquatic chelonians we compared the body shape of males and females of two aquatic turtles (Chelodina colliei and Mauremys leprosa). In both species, females were larger than males. When controlled for body size, females exhibited a greater relative internal volume and a higher body condition index than males; both traits potentially correlate positively with fecundity. Males were more streamlined (hydrodynamic), and exhibited larger openings in the shell providing more space to move their longer limbs; such traits probably improve mobility and copulation ability (the males chase and grab the female for copulation). Overall, although the specific constraints imposed by terrestrial and aquatic locomotion shape the morphology of chelonians differently (aquatic turtles were flatter, hence more hydrodynamic than terrestrial tortoises), the direction for sexual shape dimorphism remained unaffected. Our main conclusion is that the direction of sexual shape dimorphism is probably more consistent than sexual size dimorphism in the animal kingdom. PMID:20832271

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. Elucidating differences in metal absorption efficiencies between terrestrial soft-bodied and aquatic species.

    PubMed

    Owsianiak, Mikołaj; Veltman, Karin; Hauschild, Michael Z; Hendriks, A Jan; Steinmann, Zoran J N; Huijbregts, Mark A J

    2014-10-01

    It is unknown whether metal absorption efficiencies in terrestrial soft-bodied species can be predicted with the same metal properties as for aquatic species. Here, we developed models for metal absorption efficiency from the dissolved phase for terrestrial worms and several aquatic species, based on 23 metal physicochemical properties. For the worms, the absorption efficiency was successfully related to 7 properties, and is best predicted with the ionic potential. Different properties (8 in total) were found to be statistically significant in regressions predicting metal absorption in aquatic species, with the covalent index being the best predictor. It is hypothesized that metal absorption by soft-bodied species in soil systems is influenced by the rate of metal supply to the membrane, while in aquatic systems accumulation is solely determined by metal affinity to membrane bound transport proteins. Our results imply that developing predictive terrestrial bioaccumulation and toxicity models for metals must consider metal interactions with soil solids. This may include desorption of a cation bound to soil solids through ion exchange, or metal release from soil surfaces involving breaking of metal-oxygen bonds.

  3. Myeloma bone and extra-medullary disease: Role of PET/CT and other whole-body imaging techniques.

    PubMed

    Rubini, Giuseppe; Niccoli-Asabella, Artor; Ferrari, Cristina; Racanelli, Vito; Maggialetti, Nicola; Dammacco, Francesco

    2016-05-01

    Multiple myeloma (MM) is the second most common hematological malignancy. Although it can affect different organs, the bone compartment stands out both in terms of prevalence and clinical impact. Despite the striking advances in MM therapy, bone disease can remarkably affect the patient's quality of life. The occurrence and extension of bone marrow and extra-medullary involvement should be carefully assessed to confirm the diagnosis, to locate and whenever possible prevent dreadful complications such as pathological fractures and spinal cord compression, and to establish suitable therapeutic measures. Many imaging techniques have been proposed for the detection of MM skeletal involvement. With the development of more sophisticated imaging tools, it is time to use the right technique at the right time. Based on the review of the literature and our own experience, this article discusses advantages and disadvantages of the different imaging methods in the work-up of MM patients, with particular emphasis on the role that PET/CT can play. It is emphasized that whole body low-dose computed tomography should be the preferred imaging technique at baseline. However, bone marrow infiltration and extra-medullary manifestations are better detected by whole body magnetic resonance imaging. Positron emission tomography/computed tomography, on the other hand, combines the benefits of the two mentioned imaging procedures and is particularly useful not only for the detection of osteolytic lesions unrevealed by conventional X-ray, but also in the assessment of prognosis and therapeutic response. PMID:26997302

  4. Phase diagram of the alternating-spin Heisenberg chain with extra isotropic three-body exchange interactions

    NASA Astrophysics Data System (ADS)

    Ivanov, Nedko B.; Ummethum, Jörg; Schnack, Jürgen

    2014-10-01

    For the time being isotropic three-body exchange interactions are scarcely explored and mostly used as a tool for constructing various exactly solvable one-dimensional models, although, generally speaking, such competing terms in generic Heisenberg spin systems can be expected to support specific quantum effects and phases. The Heisenberg chain constructed from alternating S = 1 and σ = 1/2 site spins defines a realistic prototype model admitting extra three-body exchange terms. Based on numerical density-matrix renormalization group (DMRG) and exact diagonalization (ED) calculations, we demonstrate that the additional isotropic three-body terms stabilize a variety of partially-polarized states as well as two specific non-magnetic states including a critical spin-liquid phase controlled by two Gaussinal conformal theories as well as a critical nematic-like phase characterized by dominant quadrupolar S-spin fluctuations. Most of the established effects are related to some specific features of the three-body interaction such as the promotion of local collinear spin configurations and the enhanced tendency towards nearest-neighbor clustering of the spins. It may be expected that most of the predicted effects of the isotropic three-body interaction persist in higher space dimensions.

  5. 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.

  6. 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

  7. Body plan innovation in treehoppers through the evolution of an extra wing-like appendage.

    PubMed

    Prud'homme, Benjamin; Minervino, Caroline; Hocine, Mélanie; Cande, Jessica D; Aouane, Aïcha; Dufour, Héloïse D; Kassner, Victoria A; Gompel, Nicolas

    2011-05-01

    Body plans, which characterize the anatomical organization of animal groups of high taxonomic rank, often evolve by the reduction or loss of appendages (limbs in vertebrates and legs and wings in insects, for example). In contrast, the addition of new features is extremely rare and is thought to be heavily constrained, although the nature of the constraints remains elusive. Here we show that the treehopper (Membracidae) 'helmet' is actually an appendage, a wing serial homologue on the first thoracic segment. This innovation in the insect body plan is an unprecedented situation in 250 Myr of insect evolution. We provide evidence suggesting that the helmet arose by escaping the ancestral repression of wing formation imparted by a member of the Hox gene family, which sculpts the number and pattern of appendages along the body axis. Moreover, we propose that the exceptional morphological diversification of the helmet was possible because, in contrast to the wings, it escaped the stringent functional requirements imposed by flight. This example illustrates how complex morphological structures can arise by the expression of ancestral developmental potentials and fuel the morphological diversification of an evolutionary lineage.

  8. For Researchers on Obesity: Historical Review of Extra Body Weight Definitions.

    PubMed

    Komaroff, Marina

    2016-01-01

    Rationale. The concept of obesity has been known since ancient world; however, the current standard definition of obesity was endorsed only about a decade ago. There is a need for researches to understand multiple approaches to defining obesity and how and why the standard definition was developed. The review will help to grasp the complexity of the problem and can lead to novel hypotheses in obesity research. Objective. This paper focuses on the objective to understand historical background on the development of "reference and standard tables" of weight as a platform for normal versus abnormal body weight definition. Methods. A systematic literature review was performed to chronologically summarize the definition of body weight from time of Hippocrates till the year of 2010. Conclusion. This paper presents the historical background on the development of "reference and standard tables" of weight as a platform for normal versus abnormal body weight definition. Knowledge of historical approaches to the concept of obesity can motivate researchers to find new hypotheses and utilize the appropriate obesity assessments to address their objectives. PMID:27313875

  9. For Researchers on Obesity: Historical Review of Extra Body Weight Definitions

    PubMed Central

    Komaroff, Marina

    2016-01-01

    Rationale. The concept of obesity has been known since ancient world; however, the current standard definition of obesity was endorsed only about a decade ago. There is a need for researches to understand multiple approaches to defining obesity and how and why the standard definition was developed. The review will help to grasp the complexity of the problem and can lead to novel hypotheses in obesity research. Objective. This paper focuses on the objective to understand historical background on the development of “reference and standard tables” of weight as a platform for normal versus abnormal body weight definition. Methods. A systematic literature review was performed to chronologically summarize the definition of body weight from time of Hippocrates till the year of 2010. Conclusion. This paper presents the historical background on the development of “reference and standard tables” of weight as a platform for normal versus abnormal body weight definition. Knowledge of historical approaches to the concept of obesity can motivate researchers to find new hypotheses and utilize the appropriate obesity assessments to address their objectives. PMID:27313875

  10. Body mass estimation in xenarthra: a predictive equation suitable for all quadrupedal terrestrial placentals?

    PubMed

    De Esteban-Trivigno, Soledad; Mendoza, Manuel; De Renzi, Miquel

    2008-10-01

    The Magnorder Xenarthra includes strange extinct groups, like glyptodonts, similar to large armadillos, and ground sloths, terrestrial relatives of the extant tree sloths. They have created considerable paleobiological interest in the last decades; however, the ecology of most of these species is still controversial or unknown. The body mass estimation of extinct species has great importance for paleobiological reconstructions. The commonest way to estimate body mass from fossils is through linear regression. However, if the studied species does not have similar extant relatives, the allometric pattern described by the regression could differ from those shown by the extinct group. That is the case for glyptodonts and ground sloths. Thus, stepwise multiple regression were developed including extant xenarthrans (their taxonomic relatives) and ungulates (their size and ecological relatives). Cases were weighted to maximize the taxonomic evenness. Twenty-eight equations were obtained. The distribution of the percent of prediction error (%PE) was analyzed between taxonomic groups (Perissodactyla, Artiodactyla, and Xenarthra) and size groups (0-20 kg, 20-300 kg, and more than 300 kg). To assess the predictive power of the functions, equations were applied to species not included in the regression development [test set cross validation, (TSCV)]. Only five equations had a homogeneous %PE between the aforementioned groups. These were applied to five extinct species. A mean body mass of 80 kg was estimated for Propalaehoplophorus australis (Cingulata: Glyptodontidae), 594 kg for Scelidotherium leptocephalum (Phyllophaga: Mylodontidae), and 3,550.7 kg for Lestodon armatus (Phyllophaga: Mylodontidae). The high scatter of the body mass estimations obtained for Catonyx tarijensis (Phyllophaga: Mylodontidae) and Thalassocnus natans (Phyllophaga: Megatheriidae), probably due to different specializations, prevented us from predicting its body mass. Surprisingly, although obtained

  11. Body mass estimation in xenarthra: a predictive equation suitable for all quadrupedal terrestrial placentals?

    PubMed

    De Esteban-Trivigno, Soledad; Mendoza, Manuel; De Renzi, Miquel

    2008-10-01

    The Magnorder Xenarthra includes strange extinct groups, like glyptodonts, similar to large armadillos, and ground sloths, terrestrial relatives of the extant tree sloths. They have created considerable paleobiological interest in the last decades; however, the ecology of most of these species is still controversial or unknown. The body mass estimation of extinct species has great importance for paleobiological reconstructions. The commonest way to estimate body mass from fossils is through linear regression. However, if the studied species does not have similar extant relatives, the allometric pattern described by the regression could differ from those shown by the extinct group. That is the case for glyptodonts and ground sloths. Thus, stepwise multiple regression were developed including extant xenarthrans (their taxonomic relatives) and ungulates (their size and ecological relatives). Cases were weighted to maximize the taxonomic evenness. Twenty-eight equations were obtained. The distribution of the percent of prediction error (%PE) was analyzed between taxonomic groups (Perissodactyla, Artiodactyla, and Xenarthra) and size groups (0-20 kg, 20-300 kg, and more than 300 kg). To assess the predictive power of the functions, equations were applied to species not included in the regression development [test set cross validation, (TSCV)]. Only five equations had a homogeneous %PE between the aforementioned groups. These were applied to five extinct species. A mean body mass of 80 kg was estimated for Propalaehoplophorus australis (Cingulata: Glyptodontidae), 594 kg for Scelidotherium leptocephalum (Phyllophaga: Mylodontidae), and 3,550.7 kg for Lestodon armatus (Phyllophaga: Mylodontidae). The high scatter of the body mass estimations obtained for Catonyx tarijensis (Phyllophaga: Mylodontidae) and Thalassocnus natans (Phyllophaga: Megatheriidae), probably due to different specializations, prevented us from predicting its body mass. Surprisingly, although obtained

  12. 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

  13. Speed of Sound in Aqueous Solutions at sub-GPa Pressures: a New Experiment to Unveil the Properties of Extra-Terrestrial Oceans

    NASA Astrophysics Data System (ADS)

    Bollengier, O.; Brown, J. M.; Vance, S.; Shaw, G. H.

    2015-12-01

    Geophysical data from the Galileo and Cassini-Huygens missions are consistent with the presence of aqueous subsurface oceans in Ganymede, Callisto and Titan, the largest icy satellites of the solar system. To understand the history and present state of these moons, the next generation of evolution models will require an accurate description of the properties of these liquid layers to predict the phase boundaries, heat transports and chemical exchanges within them. Sound speed measurements in pressure and temperature allow for the reconstruction of the Gibbs free energy surface of a phase, which in turn gives access to the desired properties (chemical potential, density, heat capacity...). However, such data are still scarce for aqueous solutions bearing Na+, Mg2+, Cl- and SO42- ions (major ions expected in extra-terrestrial oceans) at the high pressures and low temperatures expected for water inside these moons (up to 1.5 GPa for Ganymede, down to freezing temperatures). For pure water, IAPWS accuracy for sound speeds is given to 0.3% above 0.4 GPa. MgSO4aqueous solutions have been explored to 0.7 GPa with a precision limited to about 0.5%. Most other aqueous solutions bearing any combination of these four ions have not been explored at all above a few hundreds MPa. To acquire new high-precision sound speeds in aqueous solutions of various compositions, we set up a new experimental system working in the 0 - 0.7 GPa pressure range and 240 - 350 K temperature range. The device consists in an oil-pressurized steel vessel enclosing a titanium alloy rod supporting the sample and a sealing bellows. A transducer at the top end of the titanium rod generates ultrasonic waves and collects the series of subsequent reflections. Preliminary tests with pure water illustrate a precision of 0.02% and an accuracy within 0.1% of IAPWS on our whole pressure range. Revision of the properties of pure water and H2O-MgSO4 solutions up to 0.7 GPa along with the first data in the H2O-MgCl2

  14. Dynamics of the terrestrial planets from a large number of N-body simulations

    NASA Astrophysics Data System (ADS)

    Fischer, Rebecca A.; Ciesla, Fred J.

    2014-04-01

    The agglomeration of planetary embryos and planetesimals was the final stage of terrestrial planet formation. This process is modeled using N-body accretion simulations, whose outcomes are tested by comparing to observed physical and chemical Solar System properties. The outcomes of these simulations are stochastic, leading to a wide range of results, which makes it difficult at times to identify the full range of possible outcomes for a given dynamic environment. We ran fifty high-resolution simulations each with Jupiter and Saturn on circular or eccentric orbits, whereas most previous studies ran an order of magnitude fewer. This allows us to better quantify the probabilities of matching various observables, including low probability events such as Mars formation, and to search for correlations between properties. We produce many good Earth analogues, which provide information about the mass evolution and provenance of the building blocks of the Earth. Most observables are weakly correlated or uncorrelated, implying that individual evolutionary stages may reflect how the system evolved even if models do not reproduce all of the Solar System's properties at the end. Thus individual N-body simulations may be used to study the chemistry of planetary accretion as particular accretion pathways may be representative of a given dynamic scenario even if that simulation fails to reproduce many of the other observed traits of the Solar System.

  15. 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.

  16. Recent spatial and temporal changes in body size of terrestrial vertebrates: probable causes and pitfalls.

    PubMed

    Yom-Tov, Yoram; Geffen, Eli

    2011-05-01

    Geographical and temporal variations in body size are common phenomena among organisms and may evolve within a few years. We argue that body size acts much like a barometer, fluctuating in parallel with changes in the relevant key predictor(s), and that geographical and temporal changes in body size are actually manifestations of the same drivers. Frequently, the principal predictors of body size are food availability during the period of growth and ambient temperature, which often affects food availability. Food availability depends on net primary productivity that, in turn, is determined by climate and weather (mainly temperature and precipitation), and these depend mainly on solar radiation and other solar activities. When the above predictors are related to latitude the changes have often been interpreted as conforming to Bergmann's rule, but in many cases such interpretations should be viewed with caution due to the interrelationships among various environmental predictors. Recent temporal changes in body size have often been related to global warming. However, in many cases the above key predictors are not related to either latitude and/or year, and it is the task of the researcher to determine which particular environmental predictor is the one that determines food availability and, in turn, body size. The chance of discerning a significant change in body size depends to a large extent on sample size (specimens/year). The most recent changes in body size are probably phenotypic, but there are some cases in which they are partly genetic.

  17. Gravitational N-body problem on the accretion process of terrestrial planets

    NASA Technical Reports Server (NTRS)

    Matsui, T.; Mizutani, H.

    1978-01-01

    Numerical integration of the gravitational N-body problem has been carried out for a variety of protoplanetary clusters in the range N = 100 to 200. Particles are assumed to coagulate at collisions irrespective of relative velocity and mass ratio of the particles. It is shown graphically how the dispersed N-bodies accumulate to a single planet through mutual collisions. The velocity distribution and size distribution of bodies are also investigated as functions of time in the accretion process. Accretion rates of planets are found to be dependent strongly on the initial number density distribution, the initial size distribution, and the initial velocity distribution of bodies. Formation of satellites of about 10% in the planet mass is common to most cases in the present study. A substantial mass of bodies also escapes from the cluster. Many satellites and escapers formed during the accretion process of planets may be source materials of heavy bombardment in the early history of planets.

  18. From planetesimals to terrestrial planets: N-body simulations including the effects of nebular gas and giant planets

    NASA Astrophysics Data System (ADS)

    Morishima, Ryuji; Stadel, Joachim; Moore, Ben

    2010-06-01

    We present results from a suite of N-body simulations that follow the formation and accretion history of the terrestrial planets using a new parallel treecode that we have developed. We initially place 2000 equal size planetesimals between 0.5 and 4.0 AU and the collisional growth is followed until the completion of planetary accretion (>100 Myr). A total of 64 simulations were carried out to explore sensitivity to the key parameters and initial conditions. All the important effect of gas in laminar disks are taken into account: the aerodynamic gas drag, the disk-planet interaction including Type I migration, and the global disk potential which causes inward migration of secular resonances as the gas dissipates. We vary the initial total mass and spatial distribution of the planetesimals, the time scale of dissipation of nebular gas (which dissipates uniformly in space and exponentially in time), and orbits of Jupiter and Saturn. We end up with 1-5 planets in the terrestrial region. In order to maintain sufficient mass in this region in the presence of Type I migration, the time scale of gas dissipation needs to be 1-2 Myr. The final configurations and collisional histories strongly depend on the orbital eccentricity of Jupiter. If today's eccentricity of Jupiter is used, then most of bodies in the asteroidal region are swept up within the terrestrial region owing to the inward migration of the secular resonance, and giant impacts between protoplanets occur most commonly around 10 Myr. If the orbital eccentricity of Jupiter is close to zero, as suggested in the Nice model, the effect of the secular resonance is negligible and a large amount of mass stays for a long period of time in the asteroidal region. With a circular orbit for Jupiter, giant impacts usually occur around 100 Myr, consistent with the accretion time scale indicated from isotope records. However, we inevitably have an Earth size planet at around 2 AU in this case. It is very difficult to obtain

  19. Miniature excitatory synaptic ion currents in the earthworm Lumbricus terrestris body wall muscles.

    PubMed

    Volkov, E M; Nurullin, L F; Nikolsky, E; Vyskocil, F

    2007-01-01

    The miniature excitatory postsynaptic currents (MEPCs) of the muscle cells of the earthworm Lumbricus terrestris were recorded by glass microelectrodes. In a single synaptic zone, three types of MEPC were recorded: a fast single-exponential type that decayed with tau =0.9 ms, a slow single-exponential with tau = 9.2 ms and a two-exponential MEPC with tau = 1.3 and 8.5 ms, respectively. The muscle cells of earthworms contain populations of yet-unidentified ionic channels that might be different from the common nicotinic and muscarinic groups of acetylcholine receptors, since these MEPCs are not sensitive to d-tubocurarine, atropine, benzohexonium or proserine. Alternatively, besides ACh receptors, the membrane may contain receptors for another yet-unidentified excitatory transmitter. PMID:17973597

  20. 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

  1. 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

  2. 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

  3. High-temperature fractionation of stable iron isotopes in terrestrial and extra-terrestrial samples determined by ultra-precise measurements with a 57Fe-58Fe double spike and MC-ICPMS

    NASA Astrophysics Data System (ADS)

    Millet, M.; Baker, J.

    2010-12-01

    We have developed techniques for precise stable Fe isotope measurement utilising a 57Fe-58Fe double spike and pseudo-high-resolution MC-ICPMS. Instrumental mass bias is corrected using a 57Fe-58Fe double spike with a spike 58Fe/57Fe ratio of 1.012. Fe isotope analyses are carried out on a Nu Plasma MC-ICPMS with a DSN-100 desolvating nebuliser system. The MC-ICPMS is operated in pseudo-high-resolution mode with a mass resolution of ca. 3000 on all Fe isotopes permitting resolution of Fe isotope peaks from argide interferences. Residual interferences in the form of tails from these Ar-based interferences are corrected for by normalizing data to analyses of bracketing standards of the IRMM-014 standard. Repeated measurement of IRMM-014 yields an external reproducibility of 0.02‰ (2sd, n=26) on δ56Fe. Fe is separated from samples using conventional anion-exchange techniques. Replicate digestions of the JF-2 alkali feldspar standard yield an external reproducibility of 0.025‰ (2sd, n=5). Based on those results, error models predict that precisions of ≤ 0.01‰ (2sd) are attainable for standards and samples by combining multiple measurements of several sample digestions. We will present ultra-precise measurements of an array of international rock standards utilizing these techniques. We have obtained precise stable Fe isotope results on silicate minerals from a range of terrestrial magmatic rocks (basalt to rhyolite) and basaltic meteorites (angrites and eucrites). These results indicate that substantial stable Fe isotope fractionations (δ56Fe = -1.0 to 0.85‰) exist in high-temperature magmatic systems on Earth, which appear to be redox-controlled. Fe2+-dominated minerals like olivine display marked enrichment in light isotopes of Fe (δ56Fe = -0.35 to -0.30‰) compared to the host basaltic melt (δ56Fe = 0.05 to 0.22‰). Conversely, clinopyroxene typically has a stable Fe isotope composition only slightly lower or similar to the host melt. Notably

  4. Reduced survival and body size in the terrestrial isopod Porcellio scaber from a metal-polluted environment.

    PubMed

    Jones, D T; Hopkin, S P

    1998-01-01

    Terrestrial isopods (woodlice) may show trade-offs in life history parameters when exposed to toxins. We have shown previously [Jones and Hopkin (1996) Functional Ecology 10, 741-750] that woodlice which survive to reproduce in sites heavily polluted with metals from an industrial smelting works do not alter their reproductive allocation. This study investigates whether there are differences in the survival and body size of Porcellio scaber from these same populations. Specimens were collected from eight sites at different distances from the Avonmouth smelter, UK. The sites represented a gradient of concentrations of Zn, Cd, Pb and Cu in the woodlice, from background levels to a grossly contaminated sites close to the smelter. In laboratory trials, the number of days survived by starved males showed a significant decline with increased concentrations of Zn in those animals. The maximum size of both sexes declined significantly from the least to the most polluted sites. The most polluted sites had significantly fewer large animals. The cost of detoxifying assimilated metals appears to be reduced energy reserves and smaller body size.

  5. The effects of temperature, desiccation, and body mass on the locomotion of the terrestrial isopod, Porcellio laevis.

    PubMed

    Dailey, Tara M; Claussen, Dennis L; Ladd, Gregory B; Buckner, Shizuka T

    2009-06-01

    Locomotion in terrestrial isopods is strongly influenced by body size and by abiotic factors. We determined the speeds of isopods of differing masses within a linear racetrack at temperatures ranging from 15 to 35 degrees C. We also predicted maximum speeds based on the Froude number concept as originally applied to vertebrates. In addition we used a circular thermal gradient to examine the temperature preferences of isopods, and we measured the effects of desiccation on locomotion. Measured speeds of the isopods progressively increased with temperature with an overall Q(10) of 1.64 and scaling exponents ranging from 0.38 to 0.63. The predicted maximum speeds were remarkably close to the measured speeds at the highest test temperature although the scaling exponents were closer to 0.15. The isopods did not exhibit a strong thermal preference within the gradient; however, they did generally avoid temperatures above 25 degrees C. Moderate desiccation had no apparent effect on locomotor performance, but there was a progressive decrease in speed once animals had lost more than 10% of their initial body mass. Though largely restricted to moist habitats, P. laevis can easily withstand short exposures to desiccating conditions, and they are capable of effective locomotion over a wide range of temperatures. Since they are nonconglobating, active escape appears to be their primary defense when threatened under exposed conditions. Although their maximum speeds may be limited both by temperature and by their inability to change gait, these speeds are clearly adequate for survival.

  6. Whole-body vibration combined with extra-load training for enhancing the strength and speed of track and field athletes.

    PubMed

    Wang, Hsiang-Hsin; Chen, Wei-Han; Liu, Chiang; Yang, Wen-Wen; Huang, Mao-Ying; Shiang, Tzyy-Yuang

    2014-09-01

    The purpose of this study was to investigate whether whole-body vibration (WBV) combined with extra-load training can enhance the strength and speed of trained athletes compared with isolated WBV training or loaded training (LT) only. Twenty-one elite male track and field athletes were randomly assigned to a loaded vibration (LV) training group (n = 7), an unloaded vibration (ULV) training group (n = 7), and a LT group (n = 7). During 4 weeks of training, the LV group received the vibration stimulus (30 Hz and 4 mm) accompanied by a load comprising 75% of the maximum voluntary contraction (MVC), the ULV group received the same vibration stimulus without any load, and the LT group received only a load of 75% MVC without any vibration stimulus. The knee extensor isometric strength, and the concentric and eccentric strength were measured using an isokinetic dynamometer at 300°·s at a 30-m sprint speed before and after the training period. A 2-way mixed analysis of variance (time × group) was used to analyze the differences. Significant time × group interactions were observed for all the dependent variables (p ≤ 0.05). Regarding the post hoc analysis results, the LV group exhibited significant improvements for all the dependent variables after training (p ≤ 0.05), whereas the ULV group exhibited significantly reduced sprint speeds (p ≤ 0.05). The LV group demonstrated significantly superior eccentric strength compared with the ULV and LT groups after training (p ≤ 0.05), and the LV group also produced significantly superior sprint speeds compared with the ULV group after training (p ≤ 0.05). Vibration combined with extra-load training for 4 weeks significantly increased the muscle strength and speed of the elite male track and field athletes.

  7. 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].

  8. 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.

  9. The effect of five weeks of Tribulus terrestris supplementation on muscle strength and body composition during preseason training in elite rugby league players.

    PubMed

    Rogerson, Shane; Riches, Christopher J; Jennings, Carl; Weatherby, Robert P; Meir, Rudi A; Marshall-Gradisnik, Sonya M

    2007-05-01

    Tribulus terrestris is an herbal nutritional supplement that is promoted to produce large gains in strength and lean muscle mass in 5-28 days (15, 18). Although some manufacturers claim T. terrestris will not lead to a positive drug test, others have suggested that T. terrestris may increase the urinary testosterone/epitestosterone (T/E) ratio, which may place athletes at risk of a positive drug test. The purpose of the study was to determine the effect of T. terrestris on strength, fat free mass, and the urinary T/E ratio during 5 weeks of preseason training in elite rugby league players. Twenty-two Australian elite male rugby league players (mean +/- SD; age = 19.8 +/- 2.9 years; weight = 88.0 +/- 9.5 kg) were match-paired and randomly assigned in a double-blind manner to either a T. terrestris (n = 11) or placebo (n = 11) group. All subjects performed structured heavy resistance training as part of the club's preseason preparations. A T. terrestris extract (450 mg.d(-1)) or placebo capsules were consumed once daily for 5 weeks. Muscular strength, body composition, and the urinary T/E ratio were monitored prior to and after supplementation. After 5 weeks of training, strength and fat free mass increased significantly without any between-group differences. No between-group differences were noted in the urinary T/E ratio. It was concluded that T. terrestris did not produce the large gains in strength or lean muscle mass that many manufacturers claim can be experienced within 5-28 days. Furthermore, T. terrestris did not alter the urinary T/E ratio and would not place an athlete at risk of testing positive based on the World Anti-Doping Agency's urinary T/E ratio limit of 4:1.

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. A COCONUT EXTRA VIRGIN OIL-RICH DIET INCREASES HDL CHOLESTEROL AND DECREASES WAIST CIRCUMFERENCE AND BODY MASS IN CORONARY ARTERY DISEASE PATIENTS.

    PubMed

    Cardoso, Diuli A; Moreira, Annie S B; de Oliveira, Glaucia M M; Raggio Luiz, Ronir; Rosa, Glorimar

    2015-11-01

    Introducción: el aceite de coco (Cocos nucifera L.) virgen extra contiene una alta proporción de ácidos grasos de cadena media que parecen contribuir a la reducción del peso y podría ayudar en la prevención secundaria de la enfermedad arterial coronaria (EAC). Objetivo: evaluar el efecto del tratamiento nutricional asociado con el consumo de aceite de coco virgen extra en los parámetros antropométricos y el perfil lipídico. Métodos: se realizó un estudio longitudinal de 116 adultos de ambos sexos que presentan CAD. Los pacientes fueron seguidos en dos etapas: en la primera etapa (basal-3 meses), se llevo a cabo un tratamiento nutricional intensivo. En la segunda etapa (3-6 días), los sujetos fueron divididos en dos grupos: grupo asociado con el consumo de aceite extra virgen de coco (GDOC) y el grupo de dieta (GD). Se realizaron mediciones mensuales antropométricas: peso, circunferencia de la cintura (CC), circunferencia del cuello (PP) e índice de masa corporal (IMC). Se tomó la presión arterial y muestras de sangre recogidas en ayunas durante 12 horas para el análisis de colesterol total y lipoproteínas, apoproteínas (Apo A-1 y B), glucosa, hemoglobina glucosilada (HbA1c) e insulina (I). Se compararon los promedios al principio y al final del estudio mediante el test t de Student-independiente. Se ajustó la presión arterial diastólica por el IMC mediante ANOVA. Los análisis se realizaron con el paquete estadístico SPSS, siendo significativa p < 0.05. Resultados: la edad media de la población fue de 62,4 ± 7,7 años, el 63,2% hombres, 70% mayores, el 77,6% con infarto de miocardio, el 52,6% con angina de pecho y el 100% con hipertensión arterial y dislipidemia. En la primera etapa del tratamiento nutricional se redujeron las concentraciones de insulina, peso, WC, IMC y PP, HbA1C, HOMA-IR y rápido, sin cambiar otros parámetros. En la segunda etapa del estudio se observó que la GDOC mantiene la reducción del peso, BMI, WC, con una

  18. Magnetic factor in solar-terrestrial relations and its impact on the human body: physical problems and prospects for research

    NASA Astrophysics Data System (ADS)

    Breus, T. K.; Binhi, V. N.; Petrukovich, A. A.

    2016-05-01

    The body of current heliobiological evidence suggests that very weak variable magnetic fields due to solar- and geomagnetic-activities do have a biological effect. Geomagnetic disturbances can cause a nonspecific reaction in the human body - a kind of general adaptation syndrome which occurs due to any external stress factor. Also, specific reactions can develop. One of the reasons discussed for the similarity between biological and heliogeophysical rhythms is that geomagnetic variations have a direct influence on organisms, although exact magnetoreception mechanisms are not yet clear. The paper briefly reviews the current state of empirical and theoretical work on this fundamental multidisciplinary problem.

  19. 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.

  20. 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

    Phua, Dominic C Y; Xu, Jianliang; 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.

  1. 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

  2. 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.

  3. Olive oil's extra benefits.

    PubMed

    2016-08-17

    Could a Mediterranean diet including extra virgin olive oil reduce the risk of breast cancer? Niki Mourouti and Demosthenes Panagiotakos' study in Evidence Based Nursing examined the effects on cancer risks of a Mediterranean diet supplemented with extra virgin olive oil. PMID:27533420

  4. 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.

  5. Terrestrial sequestration

    ScienceCinema

    Charlie Byrer

    2016-07-12

    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.

  6. Energetics and mechanics of terrestrial locomotion. IV. Total mechanical energy changes as a function of speed and body size in birds and mammals.

    PubMed

    Heglund, N C; Fedak, M A; Taylor, C R; Cavagna, G A

    1982-04-01

    This is the final paper in or series examining the link between the energetics and mechanics of terrestrial locomotion. In this paper the kinetic energy of the limbs and body relative to the centre of mass (EKE, tot of paper two) is combined with the potential plus kinetic energy of the centre of mass (ECM, tot of paper three) to obtain the total mechanical energy (excluding elastic energy) of an animal during constant average-speed locomotion. The minimum mass-specific power required of the muscles and tendons to maintain the observed oscillations in total energy, Etot/Mb, can be described by one equation: Etot/Mb = 0.478 . vg 1.53 + 0.685 . vg + 0.072 where Etot/Mb is in W kg-1 and vg is in m s-1. This equation is independent of body size, applying equally as well to a chipmunk or a quail as to a horse or an ostrich. In marked contrast, the metabolic energy consumed by each gram of an animal as it moves along the ground at a constant speed increases linearly with speed and is proportional to Mb-0.3. Thus, we have found that each gram of tissue of a 30 g quail or chipmunk running at 3 m s-1 consumes metabolic energy at a rate about 15 times that of a 100 kg ostrich, horse or human running at the same speed while their muscles are performing work at the same rate. Our measurements demonstrate the importance of storage and recovery of elastic energy in larger animals, but they cannot confirm or exclude the possibility of elastic storage of energy in small animals. It seems clear that the rate at which animals consume energy during locomotion cannot be explained by assuming a constant efficiency between the energy consumed and the mechanical work performed by the muscles. It is suggested that the intrinsic velocity of shortening of the active muscle motor units (which is related to the rate of cycling of the cross bridges between actin and myosin) and the rate at which the muscles are turned on and off are the most important factors in determining the metabolic cost

  7. Repeatability of baseline corticosterone and short-term corticosterone stress responses, and their correlation with testosterone and body condition in a terrestrial breeding anuran (Platymantis vitiana).

    PubMed

    Narayan, Edward J; Cockrem, John F; Hero, Jean-Marc

    2013-06-01

    Repeatability of physiological response variables, such as the stress hormone corticosterone, across numerous sampling occasions is an important assumption for their use as predictors of behaviour, reproduction and fitness in animals. Very few studies have actually tested this assumption in free-living animals under uncontrolled natural conditions. Non-invasive urine sampling and standard capture handling protocol have enabled the rapid quantification of baseline corticosterone and short-term corticosterone stress responses in anuran amphibians. In this study, established non-invasive methods were used to monitor physiological stress and urinary testosterone levels in male individuals of the terrestrial breeding Fijian ground frog (Platymantis vitiana). Adult male frogs (n = 20) were sampled at nighttime on three repeated occasions at intervals of 14 days during their annual breeding season on Viwa Island, Fiji. All frogs expressed urinary corticosterone metabolite responses to the capture and handling stressor, with some frogs showing consistently higher urinary corticosterone responses than others. Ranks of corticosterone values at 0, 4 and 8 h, and the corrected rank were highly significant (r = 0.75-0.99) between the three repeated sampling occasions. Statistical repeatabilities were high for baseline corticosterone (r = 0.973) and for corticosterone values at 2 h (r = 0.862), 4 h (r = 0.861), 6 h (r = 0.820) and 8 h (r = 0.926), and also for the total (inclusive of baseline corticosterone values) and the corrected integrated responses (index of the acute response) [r = 0.867 and r = 0.870]. Urinary testosterone levels also showed high statistical repeatability (r = 0.78). Furthermore, variation in baseline and short-term corticosterone stress responses was greater between individuals than within individuals. Baseline urinary corticosterone was significantly negatively correlated with the corrected integrated corticosterone response (r = -0.3, p < 0.001) but

  8. 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...

  9. 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.

  10. 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.

  11. 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 Tübingen) 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

  12. 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.

  13. Extra- and intrathoracic access.

    PubMed

    Lazarides, Miltos K; Georgakarakos, Efstratios I; Schoretsanitis, Nikolaos

    2014-01-01

    The most complex patients requiring vascular access are those with bilateral central vein occlusions. Endovascular repair of the central lesions when feasible allow upper extremity use for access. When endovascular repair is not feasible, femoral vein transposition should be the next choice. When lower limb access sites have been exhausted or are contraindicated as in obese patients and in patients with peripheral arterial obstructive disease, a range of extrathoracic "exotic" extra-anatomic access procedures as the necklace cross-chest arteriovenous (AV) grafts, the ipsilateral axillo-axillary loops, the brachial-jugular AV grafts, the axillo-femoral AV grafts or even intra-thoracic ones as the right atrial AV bypasses represent the vascular surgeon's last resort. The selection among those extra-anatomical chest-wall procedures should be based upon each patient's anatomy or patient-specific factors. PMID:24817469

  14. 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.

  15. 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

  16. One universal extra dimension in PYTHIA

    NASA Astrophysics Data System (ADS)

    ElKacimi, M.; Goujdami, D.; Przysiezniak, H.; Skands, P.

    2010-01-01

    The Universal Extra Dimensions model has been implemented in the PYTHIA generator from version 6.4.18 onwards, in its minimal formulation with one TeV -1-sized extra dimension. The additional possibility of gravity-mediated decays, through a variable number of eV -1-sized extra dimensions into which only gravity extends, is also available. The implementation covers the lowest lying Kaluza-Klein (KK) excitations of Standard Model particles, except for the excitations of the Higgs fields, with the mass spectrum calculated at one loop. 2→2 tree-level production cross sections and unpolarized KK number conserving 2-body decays are included. Mixing between iso-doublet and -singlet KK excitations is neglected thus far, and is expected to be negligible for all but the top sector. New version summaryProgram title: PYTHIA Version number: 6.420 Catalogue identifier: ACTU_v2_1 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ACTU_v2_1.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 79 362 No. of bytes in distributed program, including test data, etc.: 590 900 Distribution format: tar.gz Programming language: Fortran 77 Computer: CERN lxplus and any other machine with a Fortran 77 compiler Operating system: Linux Red Hat RAM: about 800 K words Word size: 32 bits Classification: 11.2 Catalogue identifier of previous version: ACTU_v2_0 Journal reference of previous version: Comput. Phys. Comm. 135 (2001) 238 Does the new version supersede the previous version?: Yes Nature of problem: At high energy collisions between elementary particles, physics beyond the Standard Model is searched for. Many models are being investigated, namely extra-dimensional models. Solution method: The Universal Extra Dimension model is implemented in the PYTHIA event generator. Reasons for new version

  17. Modelling meteor phenomena in the atmospheres of the Terrestrial planets.

    NASA Astrophysics Data System (ADS)

    McAuliffe, J.

    showers and approach velocities were assigned according to their likely parent bodies. For both ground-based and orbital observations the atmospheric encounter velocity of a particular shower proved to be the most important factor in determining a shower's relative detectability. Leonid- and Orionid-type high velocity showers will provide the best opportunities for future in-situ detection campaigns at Mars and Venus, and with two triple-planet approachers having already been identified a real possibility exists for comparative studies of extra-terrestrial meteor phenomena with that at the Earth. 2

  18. 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.

  19. 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

  20. 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.

  1. Extra osseous primary Ewing's sarcoma.

    PubMed

    Ali, Syed Asad; Muhammad, Agha Taj; Soomro, Abdul Ghani; Siddiqui, Akmal Jamal

    2010-01-01

    The case of 20 years old boy with an extra osseous Ewing's sarcoma is described. He was initially diagnosed as a case of infiltrative malignant tumour of left suprarenal gland on the basis of preoperative workup but postoperative biopsy of surgically excised specimen confirmed Extra-osseous Ewing's Sarcoma (EES) suprarenal gland with no evidence of malignancy on skeletal scintiscan, bone marrow aspirate and histopathology Suprarenal location of primary EES is unknown and probably has not been reported in literature. We report a unique case of EES.

  2. Extra Molting and Selection on Nymphal Growth in the Desert Locust.

    PubMed

    Pélissié, Benjamin; Piou, Cyril; Jourdan-Pineau, Hélène; Pagès, Christine; Blondin, Laurence; Chapuis, Marie-Pierre

    2016-01-01

    In insects, extra-molting has been viewed as a compensatory mechanism for nymphal growth that contributes to optimize body weight for successful reproduction. However, little is known on the capacity of extra-molting to evolve in natural populations, which limits our understanding of how selection acts on nymphal growth. We used a multi-generational pedigree, individual monitoring and quantitative genetics models to investigate the evolution of extra-molting and its impact on nymphal growth in a solitarious population of the desert locust, Schistocerca gregaria. Growth compensation via extra-molting was observed for 46% of the females, whose adult weight exceeded by 4% that of other females, at a cost of a 22% longer development time. We found a null heritability for body weight threshold only, and the highest and a strongly female-biased heritability for extra molting. Our genetic estimates show that (1) directional selection can act on growth rate, development time and extra-molting to optimize body weight threshold, the target of stabilizing selection, (2) extra-molting can evolve in natural populations, and (3) a genetic conflict, due to sexually antagonistic selection on extra-molting, might prevent its fixation. Finally, we discuss how antagonistic selection between solitarious and gregarious environments and/or genetic correlations between growth and phase traits might also impact the evolution of extra-molting in locusts.

  3. Extra Molting and Selection on Nymphal Growth in the Desert Locust

    PubMed Central

    Piou, Cyril; Jourdan-Pineau, Hélène; Pagès, Christine; Blondin, Laurence; Chapuis, Marie-Pierre

    2016-01-01

    In insects, extra-molting has been viewed as a compensatory mechanism for nymphal growth that contributes to optimize body weight for successful reproduction. However, little is known on the capacity of extra-molting to evolve in natural populations, which limits our understanding of how selection acts on nymphal growth. We used a multi-generational pedigree, individual monitoring and quantitative genetics models to investigate the evolution of extra-molting and its impact on nymphal growth in a solitarious population of the desert locust, Schistocerca gregaria. Growth compensation via extra-molting was observed for 46% of the females, whose adult weight exceeded by 4% that of other females, at a cost of a 22% longer development time. We found a null heritability for body weight threshold only, and the highest and a strongly female-biased heritability for extra molting. Our genetic estimates show that (1) directional selection can act on growth rate, development time and extra-molting to optimize body weight threshold, the target of stabilizing selection, (2) extra-molting can evolve in natural populations, and (3) a genetic conflict, due to sexually antagonistic selection on extra-molting, might prevent its fixation. Finally, we discuss how antagonistic selection between solitarious and gregarious environments and/or genetic correlations between growth and phase traits might also impact the evolution of extra-molting in locusts. PMID:27227885

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. Extra-articular Snapping Hip

    PubMed Central

    2010-01-01

    Context: Snapping hip, or coxa saltans, is a vague term used to describe palpable or auditory snapping with hip movements. As increasing attention is paid to intra-articular hip pathologies such as acetabular labral tears, it is important to be able to identify and understand the extra-articular causes of snapping hip. Evidence Acquisition: The search terms snapping hip and coxa sultans were used in PubMed to locate suitable studies of any publication date (ending date, November 2008). Results: Extra-articular snapping may be caused laterally by the iliotibial band or anteriorly by the iliopsoas tendon. Snapping of the iliopsoas tendon usually requires contraction of the hip flexors and may be difficult to differentiate from intra-articular causes of snapping. Dynamic ultrasound can help detect abrupt tendon translation during movement, noninvasively supporting the diagnosis of extra-articular snapping hip. The majority of cases of snapping hip resolve with conservative treatment, which includes avoidance of aggravating activities, stretching, and anti-inflammatory medication. In recalcitrant cases, surgery to lengthen the iliotibial band or the iliopsoas tendon has produced symptom relief but may result in prolonged weakness. Conclusions: In treating active patients with snapping soft tissues around the hip, clinicians should recognize that the majority of cases resolve without surgical intervention, while being mindful of the potential for concomitant intra-articular and internal snapping hips. PMID:23015936

  9. 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

  10. 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

  11. A molecular palaeobiological exploration of arthropod terrestrialization.

    PubMed

    Lozano-Fernandez, Jesus; Carton, Robert; Tanner, Alastair R; Puttick, Mark N; Blaxter, Mark; Vinther, Jakob; Olesen, Jørgen; Giribet, Gonzalo; Edgecombe, Gregory D; Pisani, Davide

    2016-07-19

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems.This article is part of the themed issue 'Dating species divergences using rocks and clocks'. PMID:27325830

  12. Does terrestrial epidemiology apply to marine systems?

    USGS Publications Warehouse

    McCallum, Hamish I.; Kuris, Armand M.; Harvell, C. Drew; Lafferty, Kevin D.; Smith, Garriet W.; Porter, James

    2004-01-01

    Most of epidemiological theory has been developed for terrestrial systems, but the significance of disease in the ocean is now being recognized. However, the extent to which terrestrial epidemiology can be directly transferred to marine systems is uncertain. Many broad types of disease-causing organism occur both on land and in the sea, and it is clear that some emergent disease problems in marine environments are caused by pathogens moving from terrestrial to marine systems. However, marine systems are qualitatively different from terrestrial environments, and these differences affect the application of modelling and management approaches that have been developed for terrestrial systems. Phyla and body plans are more diverse in marine environments and marine organisms have different life histories and probably different disease transmission modes than many of their terrestrial counterparts. Marine populations are typically more open than terrestrial ones, with the potential for long-distance dispersal of larvae. Potentially, this might enable unusually rapid propagation of epidemics in marine systems, and there are several examples of this. Taken together, these differences will require the development of new approaches to modelling and control of infectious disease in the ocean.

  13. A molecular palaeobiological exploration of arthropod terrestrialization

    PubMed Central

    Carton, Robert; Edgecombe, Gregory D.

    2016-01-01

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’. PMID:27325830

  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. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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…

  2. 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.

  3. Extra-Territorial Siting of Nuclear Installations

    SciTech Connect

    Shea, Thomas E.; Morris, Frederic A.

    2009-10-07

    Arrangements might be created for siting nuclear installations on land ceded by a host State for administration by an international or multinational organization. Such arrangements might prove useful in terms of resolving suspicions of proliferation in troubled areas of the world, or as a means to introduce nuclear activities into areas where political, financial or technical capabilities might otherwise make such activities unsound, or as a means to enable global solutions to be instituted for major nuclear concerns (e.g., spent fuel management). The paper examines practical matters associated with the legal and programmatic aspects of siting nuclear installations, including diplomatic/political frameworks, engaging competent industrial bodies, protection against seizure, regulation to ensure safety and security, waste management, and conditions related to the dissolution of the extra-territorial provisions as may be agreed as the host State(s) achieve the capabilities to own and operate the installations. The paper considers the potential for using such a mechanism across the spectrum of nuclear power activities, from mining to geological repositories for nuclear waste. The paper considers the non-proliferation dimensions associated with such arrangements, and the pros and cons affecting potential host States, technology vendor States, regional neighbors and the international community. It considers in brief potential applications in several locations today.

  4. Comparative Climatology of Terrestrial Planets

    NASA Astrophysics Data System (ADS)

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

    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

  5. 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.

  6. Extra Y chromosome in chronic lymphoproliferative disorders.

    PubMed

    Xiao, H; Dadey, B; Block, A W; Han, T; Sandberg, A A

    1991-02-01

    Using separated lymphocytes from 95 male patients with B-cell lymphoproliferative disorders, we have established both Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines and short-term cultures with polyclonal B-cell mitogens. Cytogenetic studies of these patients revealed an extra Y chromosome in 4 of 71 male cell lines examined. An extra Y chromosome appeared to be the sole karyotype change (47,XY, + Y) in 2 of these 4 patients. The extra Y chromosome was accompanied by extra copies of chromosomes 12 and 21 (48,XY, + Y, + 12 and 48,XY, + Y, + 21) in the other 2 patients, respectively. The possible oncological role of the extra Y chromosome in the initiation of leukemia is discussed. PMID:1847090

  7. 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

  8. 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.

  9. 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

  10. Traumatic insemination in terrestrial arthropods.

    PubMed

    Tatarnic, Nikolai J; Cassis, Gerasimos; Siva-Jothy, Michael T

    2014-01-01

    Traumatic insemination is a bizarre form of mating practiced by some invertebrates in which males use hypodermic genitalia to penetrate their partner's body wall during copulation, frequently bypassing the female genital tract and ejaculating into their blood system. The requirements for traumatic insemination to evolve are stringent, yet surprisingly it has arisen multiple times within invertebrates. In terrestrial arthropods traumatic insemination is most prevalent in the true bug infraorder Cimicomorpha, where it has evolved independently at least three times. Traumatic insemination is thought to occur in the Strepsiptera and has recently been recorded in fruit fly and spider lineages. We review the putative selective pressures that may have led to the evolution of traumatic insemination across these lineages, as well as the pressures that continue to drive divergence in male and female reproductive morphology and behavior. Traumatic insemination mechanisms and attributes are compared across independent lineages. PMID:24160423

  11. Traumatic insemination in terrestrial arthropods.

    PubMed

    Tatarnic, Nikolai J; Cassis, Gerasimos; Siva-Jothy, Michael T

    2014-01-01

    Traumatic insemination is a bizarre form of mating practiced by some invertebrates in which males use hypodermic genitalia to penetrate their partner's body wall during copulation, frequently bypassing the female genital tract and ejaculating into their blood system. The requirements for traumatic insemination to evolve are stringent, yet surprisingly it has arisen multiple times within invertebrates. In terrestrial arthropods traumatic insemination is most prevalent in the true bug infraorder Cimicomorpha, where it has evolved independently at least three times. Traumatic insemination is thought to occur in the Strepsiptera and has recently been recorded in fruit fly and spider lineages. We review the putative selective pressures that may have led to the evolution of traumatic insemination across these lineages, as well as the pressures that continue to drive divergence in male and female reproductive morphology and behavior. Traumatic insemination mechanisms and attributes are compared across independent lineages.

  12. 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

  13. 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, Sjögren'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. Sjögren'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

  14. 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.

  15. 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

  16. 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

  17. The terrestrial silica pump.

    PubMed

    Carey, Joanna C; Fulweiler, Robinson W

    2012-01-01

    Silicon (Si) cycling controls atmospheric CO(2) 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 CO(2) 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.

  18. Terrestrial photovoltaic measurement procedures

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Procedures for obtaining cell and array current-voltage measurements both outdoors in natural sunlight and indoors in simulated sunlight are presented. A description of the necessary apparatus and equipment is given for the calibration and use of reference solar cells. Some comments relating to concentration cell measurements, and a revised terrestrial solar spectrum for use in theoretical calculations, are included.

  19. 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

  20. 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.

  1. 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.

  2. Extra-cavity feedback into unstable resonators.

    PubMed

    Corkum, P B; Baldis, H A

    1979-05-01

    Unstable resonators constructed of totally reflecting optics are particularly sensitive to extra-cavity feedback. This is demonstrated experimentally by reflecting the attenuated output of an injection mode-locked TEA CO(2) laser, fitted with a confocal unstable resonator, back into the laser resonator. Even after attenuation by ~10(6), significant perturbation ( greater, similar10%) could be observed in the temporal characteristics of the output train. A theory of extra-cavity feedback in the geometric limit is presented. PMID:20212847

  3. 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.

  4. Trackways Produced by Lungfish During Terrestrial Locomotion

    PubMed Central

    Falkingham, Peter L.; Horner, Angela M.

    2016-01-01

    Some primarily aquatic vertebrates make brief forays onto land, creating traces as they do. A lack of studies on aquatic trackmakers raises the possibility that such traces may be ignored or misidentified in the fossil record. Several terrestrial Actinopterygian and Sarcopterygian species have previously been proposed as possible models for ancestral tetrapod locomotion, despite extant fishes being quite distinct from Devonian fishes, both morphologically and phylogenetically. Although locomotion has been well-studied in some of these taxa, trackway production has not. We recorded terrestrial locomotion of a 35 cm African lungfish (Protopterus annectens; Dipnoi: Sarcopterygii) on compliant sediment. Terrestrial movement in the lungfish is accomplished by planting the head and then pivoting the trunk. Impressions are formed where the head impacts the substrate, while the body and fins produce few traces. The head leaves a series of alternating left-right impressions, where each impact can appear as two separate semi-circular impressions created by the upper and lower jaws, bearing some similarity to fossil traces interpreted as footprints. Further studies of trackways of extant terrestrial fishes are necessary to understand the behavioural repertoire that may be represented in the fossil track record. PMID:27670758

  5. Comparative Climatology of Terrestrial Planets

    NASA Astrophysics Data System (ADS)

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

    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

  6. 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.

  7. 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.

  8. 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.

  9. A summary of extremes of isotopic variations in extra-terrestrial materials

    NASA Astrophysics Data System (ADS)

    Shima, M.

    1986-04-01

    In this comprehensive review of current research on isotopic variations of elements in extraterrestrial materials, the variations were classified in terms of the major process involved in the modification of the iostopic composition of the element concerned. Maximum isotopic variations of each element were retrieved from publications which were available in Tokyo up to December 1985, and are presented in tabular form.

  10. 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…

  11. 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…

  12. Long-term total ozone response caused by extra-terrestrial factors

    NASA Astrophysics Data System (ADS)

    Krivolutsky, A.; Knyazeva, N.; Perejaslova, G.; Bazilevskaya, G.; Nazarova, M.

    The observations of solar proton fluxes from boards of "Meteor", GOES satellites, galactic cosmic ray fluxes measured in the stratosphere by balloons, solar radio irradiance and total ozone records (ground based and TOMS data) for 1960-2000 period, has been used to investigate spatial and temporal structure of total ozone response to cosmic influence. Linear simple and multiply regression analysis has been used in our study. Yearly averaged data were used for analysis to e timates long-t erm effects in ozone response. Ozone data were grouped in different latitudinal belts of 100 width for Northern Hemisphere from equator to 800 N. Simple linear regression analysis for individual cosmic factors revealed negative total ozone response (in accordance to the conception of ozone destruction by additional amount of NOx produced by solar protons in the atmosphere of the Earth)0 for the years of strong solar proton events for latitudes which were higher than 45 N However, positive response for lower latitudes was found, when the same regression method was used. In the case of GCR influence on ozone the decadal response of ozone was revealed at high latitudes, which was in phase with galactic cosmic ray flux and in contract to the mentioned conception of ozone destruction by the NOx . Multiply regression analysis gave the long-term ozone variation of cosmic nature similar to real variations of total ozone.

  13. Extra and Intra-articular Synovial Chondromatosis.

    PubMed

    Chaudhary, R K; Banskota, B; Rijal, S; Banskota, A K

    2015-01-01

    Synovial chondromatosis is not so rare intra-articular condition secondary to synovial metaplasia, that affects the knee joint. Extra-articular synovial chondromatosis however is an extremely rare condition that usually involves the synovial sheath or bursa of the foot or hand. We present two cases of synovial chondromatosis, one intra and one extra-articular. The first case was a 25 year old lady who presented with pain, swelling and restricted range of motion of left knee and was found to have an intra-articular synovial chondromatosis which was treated successfully by joint debridement. The second case was that of a 22 year old man who presented with right knee pain and was diagnosed to have an extra-articular synovial chondromatosis of his right medial hamstring tendon sheath, excision of which resulted in complete relief of symptoms. PMID:27549506

  14. Extra-dimensional models on the lattice

    DOE PAGES

    Knechtli, Francesco; Rinaldi, Enrico

    2016-08-05

    In this paper we summarize the ongoing effort to study extra-dimensional gauge theories with lattice simulations. In these models the Higgs field is identified with extra-dimensional components of the gauge field. The Higgs potential is generated by quantum corrections and is protected from divergences by the higher dimensional gauge symmetry. Dimensional reduction to four dimensions can occur through compactification or localization. Gauge-Higgs unification models are often studied using perturbation theory. Numerical lattice simulations are used to go beyond these perturbative expectations and to include nonperturbative effects. We describe the known perturbative predictions and their fate in the strongly-coupled regime formore » various extra-dimensional models.« less

  15. Method for identifying anomalous terrestrial heat flows

    DOEpatents

    Del Grande, Nancy Kerr

    1977-01-25

    A method for locating and mapping the magnitude and extent of terrestrial heat-flow anomalies from 5 to 50 times average with a tenfold improved sensitivity over orthodox applications of aerial temperature-sensing surveys as used for geothermal reconnaissance. The method remotely senses surface temperature anomalies such as occur from geothermal resources or oxidizing ore bodies by: measuring the spectral, spatial, statistical, thermal, and temporal features characterizing infrared radiation emitted by natural terrestrial surfaces; deriving from these measurements the true surface temperature with uncertainties as small as 0.05 to 0.5 K; removing effects related to natural temperature variations of topographic, hydrologic, or meteoric origin, the surface composition, detector noise, and atmospheric conditions; factoring out the ambient normal-surface temperature for non-thermally enhanced areas surveyed under otherwise identical environmental conditions; distinguishing significant residual temperature enhancements characteristic of anomalous heat flows and mapping the extent and magnitude of anomalous heat flows where they occur.

  16. 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.

  17. 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.

  18. Synchronous extra-parotid Warthin's tumour.

    PubMed

    Nishikawa, H; Kirkham, N; Hogbin, B M

    1989-08-01

    Warthin's tumour (also known as adenolymphoma or papillary cystadenoma lymphomatosum) is benign and accounts for 12 per cent of all neoplasms of the parotid gland. A case of extra-parotid Warthin's tumour occurring synchronously in a peri-parotid lymph node is described. This is not a metastatic phenomenon and occurs as a result of salivary gland inclusions of local lymph nodes during the embryological development of the parotid. Extra-parotid Warthin's tumour should be regarded as a benign incidental finding and the prognosis is excellent.

  19. 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.

  20. 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.

  1. Exploring Warped Compactifications of Extra Dimensions

    NASA Astrophysics Data System (ADS)

    Dabholkar, Sujan

    In 1920s, the concept of extra dimensions was considered for the first time to unify gravity and electromagnetism. Since then there have been many developments to understand the unification of fundamental forces using extra dimensions. In this thesis, we study this idea of extra dimensions in higher dimensional gravity theories such as String Theory or Supergravity to make connections with cosmology. We construct a family of non-singular time-dependent solutions of a six-dimensional gravity with a warped geometry. The warp factor is time-dependent and breaks the translation invariance along one of the extra directions. Our solutions have the desired property of homogeneity and isotropy along the non-compact space. These geometries are supported by matter that does not violate the null energy condition. These 6D solutions do not have a closed trapped surface and hence the Hawking-Penrose singularity theorems do not apply to these solutions. These solutions are constructed from 7D locally flat solution by performing Kaluza-Klein reduction. We also study warped compactifications of string/M theory with the help of effective potentials for the construction of de Sitter vacua. The dynamics of the conformal factor of the internal metric is explored to investigate instabilities. The results works the best mainly in the case of a slowly varying warp factor. We also present interesting ideas to find AdS vacua of N=1 flux compactifications using smooth, compact toric manifolds as internal space.

  2. Extra virgin olive oil's polyphenols: biological activities.

    PubMed

    Visioli, Francesco; Bernardini, Elena

    2011-01-01

    In addition to its high proportion of oleic acid (which is considered as "neutral" in terms of cardioprotection), extra virgin olive oil is rich in phenolic compounds, which other vegetable oils do not contain. This review critically appraises the current scientific evidence of a healthful role of olive phenols, with particular emphasis on hydroxytyrosol and related molecules.

  3. 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.

  4. Precision Constraints on Extra Fermion Generations

    SciTech Connect

    Erler, Jens; Langacker, Paul

    2010-07-16

    There has been recent renewed interest in the possibility of additional fermion generations. At the same time there have been significant changes in the relevant electroweak precision constraints, in particular, in the interpretation of several of the low energy experiments. We summarize the various motivations for extra families and analyze them in view of the latest electroweak precision data.

  5. 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.

  6. Therapy for spondyloarthritis: the role of extra-articular manifestations (eye, skin).

    PubMed

    Carron, Philippe; Van Praet, Liesbet; Jacques, Peggy; Elewaut, Dirk; Van den Bosch, Filip

    2012-08-01

    Spondyloarthritis can be considered one of the prototypes (besides rheumatoid arthritis) of an inflammatory rheumatic disease. The locomotor system is prominently involved with arthritis, enthesitis, dactylitis, sacroiliitis, and/or axial disease; but besides the rheumatologic component, other body systems are frequently affected. Extra-articular manifestations are all the medical conditions and symptoms that are not directly related to the locomotor system. Besides inflammatory bowel diseases, the major concept-related extra-articular manifestations are located in the eye (acute anterior uveitis) and the skin (psoriasis). This review focuses on the possible implications of these nonrheumatologic manifestations regarding the treatment of spondyloarthritis.

  7. Terrestrial planet formation from a truncated disk -- The 'Grand Tack'

    NASA Astrophysics Data System (ADS)

    Walsh, K. J.; Morbidelli, A.; Raymond, S.; O'Brien, D. P.; Mandell, A. M.

    2012-12-01

    A new terrestrial planet formation model (Walsh et al., 2011) explores the effects of a two-stage, inward-then-outward migration of Jupiter and Saturn, as found in numerous hydrodynamical simulations of giant planet formation (Masset & Snellgrove 2001, Morbidelli & Crida 2007, Pierens & Nelson 2008, Pierens & Raymond 2011). The inward migration of Jupiter truncates the disk of planetesimals and embryos in the terrestrial planet region. Subsequent accretion in that region then forms the terrestrial planets, in particular it produces the correct Earth/Mars mass ratio, which has been difficult to reproduce in simulations with a self-consistent set of initial conditions (see, eg. Raymond et al. 2009, Hansen 2009). Additionally, the outward migration of the giant planets populates the asteroid belt with distinct populations of bodies, with the inner belt filled by bodies originating inside of 3 AU, and the outer belt filled with bodies originating from beyond the giant planets. This differs from previous models of terrestrial planet formation due to the early radial mixing of material due to the giant planet's substantial migration. Specifically, the assumption that the current radial distribution of material in the inner Solar System is reflective of the primordial distribution of material in that region is no longer necessary. We will discuss the implications of this model in relation to previous models of terrestrial planet formation as well as available chemical and isotopic constraints.

  8. Terrestrial Carbon Cycle Variability

    PubMed Central

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2, temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1), and

  9. 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

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

    NASA Astrophysics Data System (ADS)

    De Luca, A.; Tiengo, A.; D'Agostino, D.; Watson, M.; Haberl, F.; Wilms, J.

    2016-06-01

    The EXTraS project is extracting the hitherto unexplored temporal domain information buried in the serendipitous data collected by XMM-Newton/EPIC since its launch. This includes a search for fast transients, missed by standard image analysis, as well as 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 and six orders of magnitude in flux. Phenomenological classification of variable sources will also be performed. All our results, together with new analysis tools, will be made available to the community in an easy-to-use form at the end of 2016, with prospects of extending the analysis to future data. EXTraS products will have a very broad range of applications, from the search for rare events to population studies, with a large impact in almost all fields of astrophysics. This will boost the scientific exploitation of XMM data and make EPIC the reference for time-domain astronomy in the soft X-rays. The EXTraS project (2014-2016), funded within the EU/FP7 framework, is carried out by a collaboration including INAF (Italy), IUSS (Italy), CNR/IMATI (Italy), University of Leicester (UK), MPE (Germany) and ECAP (Germany).

  11. Unveiling long-term variability in XMM-Newton surveys within the EXTraS project

    NASA Astrophysics Data System (ADS)

    Rosen, S.; Read, A.; Law-Green, D.; Watson, M.; Pye, J.; O'Brien, P.

    2016-06-01

    The EXTraS project (Exploring the X-ray transient and variable sky) is an EU/FP7-Cooperation Space framework programme that aims to bring together a diverse set of time-domain analyses of XMM-Newton X-ray data and make them available to the public in a coherent manner. Through a combination of pointed observations and slew scans, XMM-Newton has repeatedly observed many regions of the sky, in a few cases up to ˜50 times, ˜70000 sources being observed more than once. While non-uniformly spaced and often sparse, these snapshots provide scientifically valuable information on the photometric behaviour of sources on longer term (hours to ˜ a decade) timescales. Here we describe the collation of XMM-Newton data for long-term variability from the 3XMM-DR5 catalogue, the slew survey and upper-limit information from the associated XMM-Newton products, and the analysis being performed on the ensuing light curves. We also present emerging examples of some newly identified long-term variable sources to highlight the value of this element of the EXTraS project. These longer baseline light curves can (i) unveil variable sources that appear stable in individual observations, (ii) reveal exotic and transient sources and (iii) complement short-term variability information from elsewhere in the EXTraS project by probing slower physical phenomena.

  12. Terrestrial planet formation with strong dynamical friction

    NASA Astrophysics Data System (ADS)

    O'Brien, David P.; Morbidelli, Alessandro; Levison, Harold F.

    2006-09-01

    We have performed 8 numerical simulations of the final stages of accretion of the terrestrial planets, each starting with over 5× more gravitationally interacting bodies than in any previous simulations. We use a bimodal initial population spanning the region from 0.3 to 4 AU with 25 roughly Mars-mass embryos and an equal mass of material in a population of ˜1000 smaller planetesimals, consistent with models of the oligarchic growth of protoplanetary embryos. Given the large number of small planetesimals in our simulations, we are able to more accurately treat the effects of dynamical friction during the accretion process. We find that dynamical friction can significantly lower the timescales for accretion of the terrestrial planets and leads to systems of terrestrial planets that are much less dynamically excited than in previous simulations with fewer initial bodies. In addition, we study the effects of the orbits of Jupiter and Saturn on the final planetary systems by running 4 of our simulations with the present, eccentric orbits of Jupiter and Saturn (the EJS simulations) and the other 4 using a nearly circular and co-planar Jupiter and Saturn as predicted in the Nice Model of the evolution of the outer Solar System [Gomes, R., Levison, H.F., Tsiganis, K., Morbidelli, A., 2005. Nature 435, 466-469; Tsiganis, K., Gomes, R., Morbidelli, A., Levison, H.F., 2005. Nature 435, 459-461; Morbidelli, A., Levison, H.F., Tsiganis, K., Gomes, R., 2005. Nature 435, 462-465] (the CJS simulations). Our EJS simulations provide a better match to our Solar System in terms of the number and average mass of the final planets and the mass-weighted mean semi-major axis of the final planetary systems, although increased dynamical friction can potentially improve the fit of the CJS simulations as well. However, we find that in our EJS simulations, essentially no water-bearing material from the outer asteroid belt ends up in the final terrestrial planets, while a large amount is

  13. 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...

  14. Extra-oral Appliances in Orthodontic Treatment.

    PubMed

    Almuzian, Mohammed; Alharbi, Fahad; McIntyre, Grant

    2016-01-01

    Extra-oral appliances are used in orthodontics to apply forces to the jaws, dentition or both and the popularity of these appliances is cyclical. Although the use of retraction headgear for the management of Class II malocclusion has declined over the last 20 years with the refinement of non-compliance approaches, including temporary anchorage devices, headgear still has a useful role in orthodontics. The use of protraction headgear has increased as more evidence of its effectiveness for the treatment of Class lIl malocclusion has become available. This paper describes the mechanics and contemporary uses of headgear in orthodontics for primary care dentists and specialist orthodontists. CPD/CLINICAL RELEVANCE: Extra-oral appliances have specific uses in orthodontic biomechanics. Clinicians using retraction headgear and protraction headgear should be familiar with their clinical indications, the potential problems and how these can be avoided.

  15. Intra-Extra Vehicular Activity Apollo Spacesuits

    NASA Technical Reports Server (NTRS)

    Thomas, Kenneth S.

    2016-01-01

    Kenneth Thomas will discuss the Apollo Intra-Extra Vehicular Activity (IEVA) spacesuits, which supported launch and reentry and extra-vehicular activity. This program was NASA's first attempt to develop a new suit design from requirements and concepts. Mr. Thomas will chronicle the challenges, developments, struggles, and solutions that culminated in the system that allowed the first human exploration of the Moon and deep space (outside low-Earth orbit). Apollo pressure suit designs allowed the heroic repair of the Skylab space station and supported the first U.S. and Russian spacecraft docking during the Apollo Soyuz Test Project. Mr. Thomas will also discuss the IEVA suits' successes and challenges associated with the IEVA developments of the 1960s.

  16. 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 ...

  17. Signals for Extra Dimensions at CLIC

    SciTech Connect

    Rizzo, Thomas G.

    2001-08-28

    A brief overview is presented of the signatures for several different models with extra dimensions at CLIC, an e{sup +}e{sup -} linear collider with a center of mass energy of 3-5 TeV and an integrated luminosity of order 1 ab{sup -1}. In all cases the search reach for the resulting new physic signatures is found to be in the range of {approx} 15-80 TeV.

  18. Extra-corporeal shock wave lithotripsy.

    PubMed Central

    Pemberton, J.

    1987-01-01

    Extra-corporeal shock wave lithotripsy (ESWL) has proved to be a revolutionary advance in the treatment of renal stone disease. It, itself, is non-invasive but may necessitate or be used as an adjunct to more invasive auxiliary procedures. The basic principles of lithotripsy, the clinical experience thus far and probable future applications are discussed. Images Figure 2 Figure 4 Figure 5 Figure 7 Figure 8 PMID:3330235

  19. 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.

  20. 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.

  1. 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

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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.

  8. Determination of Meteoroids Dynamical Properties for Terrestrial Strewn Fields by Numerical Modeling

    NASA Astrophysics Data System (ADS)

    Bronikowska, M.; Artemieva, N. A.; Wünnemann, K.; Szczuciński, W.

    2016-08-01

    Strewn fields resulting from the disruption of cosmic bodies are common on planetary surfaces. Existing physical models of meteoroid interaction with the atmosphere enable to determine entry parameters of such events for terrestrial strewn fields.

  9. 46 CFR Sec. 8 - Extra work and changes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Extra work and changes. Sec. 8 Section 8 Shipping... Sec. 8 Extra work and changes. (a) At any time after the award of an original job order and during the time the work thereunder is being performed, additional or extra work or changes in the work covered...

  10. 46 CFR Sec. 8 - Extra work and changes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Extra work and changes. Sec. 8 Section 8 Shipping... Sec. 8 Extra work and changes. (a) At any time after the award of an original job order and during the time the work thereunder is being performed, additional or extra work or changes in the work covered...

  11. 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 ...

  12. The Cosmochemistry of Terrestrial Xenon

    NASA Astrophysics Data System (ADS)

    Gilmour, J. D.; Parai, R.

    2016-08-01

    As an alternative to seeking specific meteoritic xenon signatures in the Earth, we investigate how the processes that relate meteoritic xenon to the solar composition can account for the variation observed among terrestrial xenon signatures.

  13. Radiocarbon dating of terrestrial carbonates

    USGS Publications Warehouse

    Pigati, Jeffrey S.; Rink, W. Jack; Thompson, Jeroen

    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.

  14. 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

  15. 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

  16. Laryngeal Leishmaniasis with Extra-pulmonary Tuberculosis.

    PubMed

    Tayal, Swati; Khatiwada, Saurav; Sehrawat, Priyanka; Nischal, Neeraj; Jorwal, Pankaj; Soneja, Manish; Sharma, M C; Sharma, S K; Verma, Pankaj; Singh, Anup

    2015-09-01

    Clinical presentations of Leishmania infection include visceral (most common form), cutaneous, mucocutaneous, mucosal and post-kala-azar dermal leishmaniasis. Mucosal form of leishmaniasis mostly involves oral and nasal mucosa. Rarely, laryngeal and pharyngeal mucosa may also be involved. Its concomitant presence with tuberculosis (TB), a disease rampant in India, is uncommon. Here we are reporting a case of isolated laryngeal leishmaniasis associated with extra-pulmonary tuberculosis (EPTB), with approach to diagnosis and treatment in a tropical resource-limited setting. PMID:27608871

  17. Split universal extra dimension and dark matter

    SciTech Connect

    Park, Seong Chan; Shu Jing

    2009-05-01

    Motivated by the recent observation of the high energy electron and positron excesses in cosmic ray by PAMELA and ATIC/PPB-BETS, we suggest an anomaly-free scenario for the universal extra dimension that localizes the standard model quarks and splits the spectrum of Kaluza-Klein (KK) quarks from KK leptons. When the SM quarks are 'well localized' at the boundaries, the most stringent bound of the model (1/R>510 GeV) comes from the resonance search for the Tevatron dijet channels. Even at the early stage of LHC, one can discover the second KK gluon for masses up to 4 TeV.

  18. Multigravity from a discrete extra dimension

    NASA Astrophysics Data System (ADS)

    Deffayet, C.; Mourad, J.

    2004-06-01

    Multigravity theories are constructed from the discretization of the extra dimension of five-dimensional gravity. Using an ADM decomposition, the discretization is performed while maintaining the four-dimensional diffeomorphism invariance on each site. We relate the Goldstone bosons used to realize nonlinearly general covariance in discretized gravity to the shift fields of the higher-dimensional metric. We investigate the scalar excitations of the resulting theory and show the absence of ghosts and massive modes; this is due to a local symmetry inherited from the reparametrization invariance along the fifth dimension.

  19. 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.

  20. 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

  1. Practicality of Using Oxygen Atom Emissions to Evaluate the Habitability of Extra-Solar Planets

    NASA Astrophysics Data System (ADS)

    Slanger, T. G.

    2005-12-01

    It has previously been proposed [Akasofu, 1999] that observation of the O(1S - 1D) green line from the atmospheres of extra-solar planets might be a marker for habitability. Guidance on this question is available within our own solar system. The green line is a dominant feature in the visible terrestrial nightglow, and the ultimate origin of its mesospheric emission is the three-body recombination of oxygen atoms. Until recently, it was believed that the green line was not a feature of the nightglows of the CO2 planets, Venus and Mars. It is now known that Venus at times shows green line emission with an intensity equal to terrestrial values [Slanger et al., 2001]. Furthermore, the intensity is quite variable, as is true for the much stronger O2( a-X) 1.27 μ emission. Recent observations of the Mars nightglow [Bertaux et al., 2005] give ambiguous results in the region of the O(1S-3P) line at 297.2 nm, but the same line in the dayglow is very strong, as evidenced in earlier Mariner results [Barth et al., 1971], and from the recent Mars Express data [F. Leblanc, private communication]. The O(1D-3P) 630 nm red line is a feature associated with Io, where dissociation of SO2 is a presumed source [Scherb et al., 1998]. Thus, observation of the oxygen green/red lines in the atmospheres of extrasolar planets provides insufficient information to reach conclusions about a habitable environment. Such detection would only indicate that there are oxygen-containing molecules present. Determination of an O2 column depth, by Fraunhofer A-band absorption, would be much more conclusive. Akasofu, S.-I., EOS, Transactions of the American Geophysical Union, 80, 397, 1999. Barth, C.A., C.W. Hord, J.B. Pearce, K.K. Kelly, G.P. Anderson, and A.I. Stewart, Mariner 6 and 7 Ultraviolet Spectrometer Experiment: Upper Atmosphere Data, Journal of Geophysical Research, 76, 2213-2227, 1971. Bertaux, J.-L., F. Leblanc, S. Perrier, E. Quemerais, O. Korablev, E. Dimarellis, A. Reberac, F. Forget, P

  2. 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.

  3. Flavor structure of warped extra dimension models

    SciTech Connect

    Agashe, Kaustubh; Perez, Gilad; Soni, Amarjit

    2005-01-01

    We recently showed that warped extra-dimensional models with bulk custodial symmetry and few TeV Kaluza-Klein (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 new physics 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.

  4. 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.

  5. Extra Pay for Extra Duties of Teachers, 1974-75. ERS Report.

    ERIC Educational Resources Information Center

    Stieber, Gertrude N.

    This report presents a system-by-system listing of extra pay for athletic and nonathletic extracurricular teacher activities. The data is drawn from the information supplied in connection with the Educational Research Service "National Survey of Salaries and Wages in Public Schools, 1974-75." Table 1 shows the number of school systems reporting…

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

    NASA Astrophysics Data System (ADS)

    Tiengo, Andrea

    Modern soft X-ray observatories can yield unique insights into time domain astrophysics. Indeed, a huge amount of information is stored - and largely unexploited - in data archives. The EXTraS project will harvest 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 in more than 13 yr of observations. This will include a search for fast transients, missed by standard image analysis, as well as a search and characterization of variability (both periodical and aperiodical) in hundreds of thousands of sources spanning more than nine orders of magnitude in time scale (from <1 s to >10 yr) and six orders of magnitude in flux (from 10(-9) to 10(-15) erg cm(-2) s(-1) in 0.2-12 keV). X-ray results will be complemented by multiwavelength characterization of all previously undetected sources. Phenomenological classification of variable sources will also be performed. All our results will be made available to the community in a public catalogue, together with new analysis tools. The EXTraS project, funded within the EU/FP7-Cooperation Space framework, is carried out by a collaboration including INAF (Italy), IUSS (Italy), CNR/IMATI (Italy), University of Leicester (UK), MPE (Germany) and ECAP (Germany).

  7. Unveiling long-term variability in XMM-Newton surveys: the EXTraS project

    NASA Astrophysics Data System (ADS)

    Rosen, S.; Read, A.; De Luca, A.; EXTraS Collaboration

    2014-07-01

    The 3XMM-DR4 catalogue, the XMM-Newton Slew Survey (XSS) and the associated XMM-Newton EPIC data, are extensive resources for exploring high energy, time-domain astrophysics. Amongst these data are potential, hitherto unidentified variable sources, ranging from short duration (~seconds) transients through to objects varying on timescales of years. Variability signatures can be key to understanding the energetics and physical processes in a diverse range of astrophysical settings. The EU/FP7-Cooperation Space framework project, `Exploring the X-ray transient and variable sky' (EXTraS), aims to exploit these XMM-Newton resources to explore, as fully as possible, the range of X-ray variability present and provide the results to the community through a public database. Here we outline one of the project's core aims, i.e. identifying and characterising long-term (days to years) variability. The 3XMM-DR4 catalogue contains ˜67000 sources with multiple detections. 3XMM, in conjunction with the XSS, which has now covered almost 70% of the sky, often with multiple slews, offers excellent scope for identifying new variable objects by tracking their flux between XMM-Newton observations. We discuss the plans for the EXTraS long-term variability catalogue and highlight some examples of the detection of long-term variability in 3XMM-DR4/XSS data.

  8. Mercury cycling in terrestrial watersheds

    USGS Publications Warehouse

    Shanley, James B.; Bishop, Kevin; Banks, Michael S.

    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.

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. Perfect-fluid cosmologies with extra dimensions

    NASA Astrophysics Data System (ADS)

    Gleiser, Reinaldo J.; Diaz, Mario C.

    1988-06-01

    We give an analysis of the solutions of the n-dimensional vacuum Einstein equations with a metric in the form of a direct sum of a Friedmann-Robertson-Walker (FRW) metric and a Kasner-type Euclidean metric. The solutions are interpreted as four-dimensional perfect-fluid cosmological FRW models, using the simple ansatz proposed by Ibán~ez and Verdaguer. We first obtain the general solution for flat models. These are perfect-fluid solutions that can be made compatible with contraction of all the extra dimensions. The general compatibility of the field equations is then discussed. It is found that for n>5 both open and closed models admit a range of perfect-fluid solutions whose qualitative behavior is analyzed.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. Extra echo spaces: ultrasonography and computerised tomography correlations.

    PubMed Central

    Wada, T; Honda, M; Matsuyama, S

    1982-01-01

    Among the echocardiograms of 844 patients of the International Goodwill Hospital from January 1980 to April 1981, 700 showed clinically inexplicable extra echo spaces. Fifty of the 700 had computerised tomography of their hearts which showed the extra echo spaces to be caused either by anterior or posterior subepicardial fat. Six of the 50 cases had both fat and pericardial effusions, which are difficult to differentiate echocardiographically unless follow-up clinical observations are performed. Subepicardial fat deposits are reasonable explanations for the extra echo spaces frequently observed by echocardiography: they correlate well with clinical findings. Subepicardial fat should be recognised as the cause of such extra echo spaces. Images PMID:7073903

  20. In situ observations of the atmospheres of terrestrial planetary bodies

    NASA Astrophysics Data System (ADS)

    Harri, Ari-Matti

    2005-11-01

    Direct observations of planetary atmospheres are scarce and significantly more data are needed for the understanding of their behavior. The principal theme of this dissertation is the exploration of planetary atmospheres by means of in situ observations, focusing on investigations performed by payloads operating on the planetary surface. The contextual frame includes the whole palette of planetary exploration including definition of scientific objectives, observational strategies, scientific payload and data analysis, as well as development of technological solutions and simulation models for planetary missions. Thus approach also led to the initiation of the planetary missions MetNet and NetLander to Mars. This work contributes to both in situ atmospheric observations and atmospheric modeling, which are strongly intertwined. Modeling efforts require observations to give solid background and foundation for the simulations, and on the other hand, definition of observational strategies and instrumentation gets guidance from modeling efforts to optimize the use of mission resources, as is successfully demonstrated in this dissertation. The dissertation consists of Summary and nine original scientific publications. Publications 1 to 7 and Summary address the development of new atmospheric science payloads for exploration missions to Mars and Titan, a Saturnian moon. Actual and planned missions included are the Mars-96 Program and its Small Surface Stations and Penetrators during the years 1988-1996, PPI/HASI onboard the Cassini/Huygens spacecraft to Saturn and its moon Titan in 1989-2005, the MET-P payload onboard the Mars Polar Lander in 1997-1999, the BAROBIT instrument for the Beagle 2 lander in 2001-2003, the NetLander Mars Mission in 1997-2001 and the ongoing Mars MetNet Mission, started in 2000. Specifically, Publication 4 reviews the sensor qualification process that facilitated the use of new type of atmospheric sensors at Mars, while Publications 2 and 7, as well as Summary, address the highly successful determination of the Titan atmospheric pressure profile. Publication 8 combines in situ observations and simulations by analyzing Mars Pathfinder measurements with the help of a Martian mesoscale atmospheric model. Finally, in Publication 9 the effect of airborne dust and CO 2 on the radiative transfer in the Martian atmosphere is assessed and a new radiative transfer paramerization scheme for the mesoscale model is introduced.

  1. Magnetic field generation in the cores of terrestrial bodies

    NASA Technical Reports Server (NTRS)

    Runcorn, S. K.

    1985-01-01

    Efforts to find some scaling law for the dipole moments of planets seem illusory for, although dynamo theory is still in a rudimentary state, once the critical magnetic Reynolds Number is exceeded it appears that the field strength is determined by the energy source, it it is permissible to treat the core as a heat engine. For this reason the lunar magnetic field is of special significance as the paleomagnetic evidence strongly suggests that the surface field was about 1 G 3.9 by diminishing exponentially to about .02 G 3.2 by ago and completely disappearing some time later.

  2. 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 ρ and range-rate ρ-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 1–2 × 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 Δdot 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.

  3. Science with the EXTraS Project: Exploring the X-Ray Transient and Variable Sky

    NASA Astrophysics Data System (ADS)

    De Luca, A.; Salvaterra, R.; Tiengo, A.; D'Agostino, D.; Watson, M. G.; Haberl, F.; Wilms, J.

    The EXTraS project ("Exploring the X-ray Transient and variable Sky") will characterise the temporal behaviour of the largest ever sample of objects in the soft X-ray range (0.1-12 keV) with a complex, systematic and consistent analysis of all data collected by the European Photon Imaging Camera (EPIC) instrument onboard the ESA XMM-Newton X-ray observatory since its launch. We will search for, and characterize variability (both periodic and aperiodic) in hundreds of thousands of sources spanning more than nine orders of magnitude in time scale and six orders of magnitude in flux. We will also search for fast transients, missed by standard image analysis. Our analysis will be completed by multiwavelength characterization of new discoveries and phenomenological classification of variable sources. All results and products will be made available to the community in a public archive, serving as a reference for a broad range of astrophysical investigations.

  4. 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

  5. Wolbachia in Neotropical terrestrial isopods.

    PubMed

    Zimmermann, Bianca L; Bouchon, Didier; Almerão, Maurício 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.

  6. 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.

  7. 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

  8. 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

  9. [Extra-thoracic solitary fibrous tumor. Report of 2 cases].

    PubMed

    Trabelsi, Amel; Mestiri, Sarra; Mokni, Moncef; Stita, Wided; Ikram, Bellara; Sriha, Badreddine; Korbi, Sadok

    2006-09-01

    The solitary fibrous tumor (SFT), is an unusual entity, first described in the pleura, but can involve other serosal surfaces and viscera. We report two cases of extra-thoracic SFT involving the retro-peritoneum and the upper arm. Extra-thoracic TFS is a rarily wide morphologic and evolutive spectrum.

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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... CONSTRUCTION AND MAINTENANCE Contract Procedures § 635.120 Changes and extra work. (a) Following authorization... work shall have formal approval by the Division Administrator in advance of their effective...

  15. 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... CONSTRUCTION AND MAINTENANCE Contract Procedures § 635.120 Changes and extra work. (a) Following authorization... work shall have formal approval by the Division Administrator in advance of their effective...

  16. Quantifying inbreeding avoidance through extra-pair reproduction.

    PubMed

    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.

  17. Extra cellular matrix features in human meninges.

    PubMed

    Montagnani, S; Castaldo, C; Di Meglio, F; Sciorio, S; Giordano-Lanza, G

    2000-01-01

    We collected human fetal and adult normal meninges to relate the age of the tissue with the presence of collagenous and non-collagenous components of Extra Cellular Matrix (ECM). Immunohistochemistry led us to observe some differences in the amount and in the distribution of these proteins between the two sets of specimens. In particular, laminin and tenascin seem to be expressed more intensely in fetal meninges when compared to adult ones. In order to investigate whether the morphofunctional characteristics of fetal meninges may be represented in pathological conditions we also studied meningeal specimens from human meningiomas. Our attention was particularly focused on the expression of those non-collagenous proteins involved in nervous cell migration and neuronal morphogenesis as laminin and tenascin, which were present in lesser amount in normal adult specimens. Microscopical evidences led us to hipothesize that these proteins which are synthesized in a good amount during the fetal development of meninges can be newly produced in tumors. On the contrary, the role of tenascin and laminin in adult meninges is probably only interesting for their biophysical characteristics.

  18. 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.

  19. Diphoton resonance from a warped extra dimension

    NASA Astrophysics Data System (ADS)

    Bauer, Martin; Hörner, Clara; Neubert, Matthias

    2016-07-01

    We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with {O} (1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the Sto γ γ, W W,ZZ,Zγ, toverline{t} and dijet decay rates. We find that the S → Zγ decay mode is strongly suppressed, such that Br( S → Zγ) /Br( S → γγ) < 0 .1. The hierarchy problem for the new scalar boson is solved in analogy with the Higgs boson by localizing it near the infrared brane. The infinite sums over the Kaluza-Klein towers of fermion states converge and can be calculated in closed form with a remarkably simple result. Reproducing the observed pp → S → γγ signal requires Kaluza-Klein masses in the multi-TeV range, consistent with bounds from flavor physics and electroweak precision observables.

  20. 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.

  1. Body Hair

    MedlinePlus

    ... girlshealth.gov/ Home Body Puberty Body hair Body hair Even before you get your first period , you ... removing pubic hair Ways to get rid of hair top Removing body hair can cause skin irritation, ...

  2. Terrestrial photovoltaic collector technology trends

    NASA Technical Reports Server (NTRS)

    Shimada, K.; Costogue, E.

    1984-01-01

    Following the path of space PV collector development in its early stages, terrestrial PV technologies based upon single-crystal silicon have matured rapidly. Currently, terrestrial PV cells with efficiencies approaching space cell efficiencies are being fabricated into modules at a fraction of the space PV module cost. New materials, including CuInSe2 and amorphous silicon, are being developed for lowering the cost, and multijunction materials for achieving higher efficiency. Large grid-interactive, tracking flat-plate power systems and concentrator PV systems totaling about 10 MW, are already in operation. Collector technology development both flat-plate and concentrator, will continue under an extensive government and private industry partnership.

  3. Beyond Earth: Using Google Earth to Visualize Other Planetary Bodies

    NASA Astrophysics Data System (ADS)

    Hancher, M.; Beyer, R.; Broxton, M.; Gorelick, N.; Kolb, E.; Weiss-Malik, M.

    2008-12-01

    Virtual globes have revolutionized the way we visualize and understand the Earth, but there are other planetary bodies that can be visualized as well. We will demonstrate the use of Google Earth, KML, and other modern mapping tools for visualizing data that's literally out of this world. Extra-terrestrial virtual globes are poised to revolutionize planetary science, bring an exciting new dimension to science education, and allow users to explore the increasingly breathtaking imagery being sent back to Earth by modern planetary science satellites. We will demonstrate several uses of the latest Google Earth and KML features to visualize planetary data. Global maps of planetary bodies---not just visible imagery maps, but also terrain maps, infra-red maps, minerological maps, and more---can be overlaid on the Google Earth globe using KML, and a number of sources are already making many such maps available. Coverage maps show the polygons that have been imaged by various satellite sensors, with links to the imagery and science data. High-resolution regionated ground overlays allow you to explore the most breathtaking imagery at full resolution, in its geological context, just as we have become accustomed to doing with Earth imagery. Panoramas from landed missions to the Moon and Mars can even be embedded, giving users a first-hand experience of other worlds. We will take you on a guided tour of how these features can best be used to visualize places other than the Earth, and provide pointers to KML from many sources---ourselves and others---that users can build on in constructing their own KML content of other planetary bodies. Using this paradigm for sharing geospatial data will not only enable planetary scientists to more easily build and share data within the scientific community, but will also provide an easy platform for public outreach and education efforts, and will easily allow anyone to layer geospatial information on top of planetary data.

  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. 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

  6. 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.

  7. Extra-cellular volume estimation by electrical impedance--phase measurement or curve fitting: a comparative study.

    PubMed

    Goovaerts, H G; Faes, T J; de Valk-de Roo, G W; ten Bolscher, M; Netelenbosch, J C; van der Vijgh, W J; Heethaar, R M

    1998-11-01

    In order to determine body fluid shifts between the intra- and extra-cellular spaces, multifrequency impedance measurement is performed. According to the Cole-Cole extrapolation, lumped values of intra- and extra-cellular conduction can be estimated which are commonly expressed in resistances Ri and Re respectively. For this purpose the magnitude and phase of the impedance under study are determined at a number of frequencies in the range between 5 kHz and 1 MHz. An approach to determine intra- and extra-cellular conduction on the basis of Bode analysis is presented in this article. On this basis, estimation of the ratio between intra- and extra-cellular conduction could be performed by phase measurement only, midrange in the bandwidth of interest. An important feature is that the relation between intra- and extra-cellular conduction can be continuously monitored by phase measurement and no curve fitting whatsoever is required. Based on a two frequency measurement determining Re at 4 kHz and phi(max) at 64 kHz it proved possible to estimate extra-cellular volume (ECV) more accurately compared with the estimation based on extrapolation according to the Cole-Cole model in 26 patients. Reference values of ECV were determined by sodium bromide. The results show a correlation of 0.90 with the reference method. The average error of ECV estimation was -3.6% (SD 8.4), whereas the Cole-Cole extrapolation showed an error of 13.2% (SD 9.5). An important feature of the proposed approach is that the relation between intra- and extra-cellular conduction can be continuously monitored by phase measurement and no curve fitting whatsoever is required.

  8. Estimation of focal and extra-focal radiation profiles based on Gaussian modeling in medical linear accelerators.

    PubMed

    Anai, Shigeo; Arimura, Hidetaka; Nakamura, Katsumasa; Araki, Fujio; Matsuki, Takaomi; Yoshikawa, Hideki; Yoshidome, Satoshi; Shioyama, Yoshiyuki; Honda, Hiroshi; Ikeda, Nobuo

    2011-07-01

    The X-ray source or focal radiation is one of the factors that can degrade the conformal field edge in stereotactic body radiotherapy. For that reason, it is very important to estimate the total focal radiation profiles of linear accelerators, which consists of X-ray focal-spot radiation and extra-focal radiation profiles. Our purpose in this study was to propose an experimental method for estimating the focal-spot and extra-focal radiation profiles of linear accelerators based on triple Gaussian functions. We measured the total X-ray focal radiation profiles of the accelerators by moving a slit in conjunction with a photon field p-type silicon diode. The slit width was changed so that the extra-focal radiation could be optimally included in the total focal radiation. The total focal radiation profiles of an accelerator at 4-MV and 10-MV energies were approximated with a combination of triple Gaussian functions, which correspond to the focal-spot radiation, extra-focal radiation, and radiation transmitted through the slit assembly. As a result, the ratios of the Gaussian peak value of the extra-focal radiation to that of the focal spot for 4 and 10 MV were 0.077 and 0.159, respectively. The peak widths of the focal-spot and extra-focal radiation profiles were 0.57 and 25.0 mm for 4 MV, respectively, and 0.60 and 22.0 mm for 10 MV, respectively. We concluded that the proposed focal radiation profile model based on the triple Gaussian functions may be feasible for estimating the X-ray focal-spot and extra-focal radiation profiles.

  9. Comparison of Titan's north polar lakes with terrestrial analogs

    NASA Astrophysics Data System (ADS)

    Sharma, Priyanka; Byrne, Shane

    2011-12-01

    The discovery of hydrocarbon lakes in the polar regions of Titan offers a unique opportunity to compare terrestrial lakes with those in an extraterrestrial setting. We selected 114 terrestrial lakes formed by different processes as analogs for comparison with the 190 Titanian lakes that we had mapped in our previous study. Using the Shuttle Radar Topography Mission (SRTM) C-band backscatter data and the SRTM Water Body Data (SWBD), we carried out an assessment of manual mapping versus existing automated mapping techniques, and found the automated techniques to produce as good representations of the lake shorelines as the manual mapping in the terrestrial dataset. We then calculated and compared terrestrial and Titanian shoreline statistical parameters including fractal dimension, shoreline development index and an elongation index. We found different lake generation mechanisms on Earth produce “statistically different” shorelines. However, we cannot identify any one mechanism or set of mechanisms to be responsible for forming the depressions enclosing the lakes on Titan, on the basis of our statistical analyses.

  10. 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.

  11. 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.

  12. 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

  13. Natural organobromine in terrestrial ecosystems

    NASA Astrophysics Data System (ADS)

    Leri, Alessandra C.; Myneni, Satish C. B.

    2012-01-01

    Recent studies have shown that bromine undergoes biogeochemical cycling involving natural formation and degradation of organobromine compounds in marine systems. In the terrestrial environment, where background bromine levels tend to be low, the biogeochemistry of this element remains largely unexamined. We traced the path of bromine through plant growth, senescence, and decay of leaf litter on the forest floor. Using sensitive X-ray spectroscopic techniques, we show that all bromine in humified plant material, organic-rich surface soils, and isolated humic substances is bonded to carbon. Analysis of bromide-enriched plants suggests that bromide absorbed by the growing plants ultimately converts to organobromine when the plant litter decays. Application of isolated chloroperoxidase, a halogenating enzyme, to healthy plant material results in extensive bromination, with organobromine formed preferentially over organochlorine. The relative ease of bromide oxidation appears to promote biogeochemical transformations of Br from inorganic to organic forms, leading to its incorporation into soil organic matter through enzymatic processes related to plant litter decomposition. In combination with low concentration and susceptibility to leaching and plant uptake, natural bromination processes lead to the exhaustion of inorganic bromide in surface soils, making organic matter a reservoir of bromine in the terrestrial environment. This study provides the first detailed look into the terrestrial bromine cycle and lays the foundation for future studies of natural organobromine degradation, which may shed light on the fate of anthropogenic organobromine pollutants in the soil environment.

  14. 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.

  15. 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

  16. 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).

  17. Workshop on Oxygen in the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    2004-01-01

    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

  18. 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

  19. 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

  20. 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.

  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. Extra-mammary findings on breast MRI: a pictorial review.

    PubMed

    Karp, Norna L; Price, Elissa R; Wisner, Dorota J; Chang, C Belinda; Hylton, Nola M; Joe, Bonnie N

    2015-01-01

    Recent improvements in breast coil performance have made detection of extra-mammary findings increasingly common. Some of these findings have important clinical implications. The radiologist should be aware of the spectrum of extra-mammary pathologies found on breast magnetic resonance imaging (MRI) and be able to distinguish clinically significant findings from those that are inconsequential. The purpose of this essay is to demonstrate various common and uncommon extra-mammary findings encountered while interpreting breast MRI and to detail appropriate management recommendations.

  3. Effects of reference objects and extra-retinal information about pursuit eye movements on curvilinear path perception from retinal flow.

    PubMed

    Cheng, Joseph C K; Li, Li

    2012-03-12

    We have previously shown that when traveling on a circular path, observers use the rotation in the retinal velocity field for path curvature estimation and recover their path of forward travel relative to their perceived instantaneous heading (L. Li, & J. C. K. Cheng, 2011). Here, we examined the contribution of reference objects and extra-retinal information about pursuit eye movements to curvilinear path perception. In Experiment 1, the display simulated an observer traveling on a circular path over a textured ground with and without tall posts while looking at a fixed target on the future path, along heading, or along a fixed axis in the world. We found that reference objects did not help path perception. In Experiment 2, extra-retinal signals about pursuit eye movements were introduced in two viewing conditions: one that corresponded to the natural case of traveling on a circular path when the body orientation is aligned with the instantaneous heading and one that corresponded to the unnatural case of traveling when the body orientation is fixed relative to the world. We found that extra-retinal signals support accurate path perception only for the natural case of self-motion when the body orientation is aligned with heading such that pursuit compensation helps stabilize the heading in the body-centric coordinate system.

  4. Cosmological constraints on theories with large extra dimensions

    SciTech Connect

    Hall, Lawrence J.; Smith, David

    1999-04-23

    In theories with large extra dimensions, constraints from cosmology lead to non-trivial lower bounds on the gravitational scale M, corresponding to upper bounds on the radii of the compact extra dimensions. These constraints are especially relevant to the case of two extra dimensions, since only if M is 10 TeV or less do deviations from the standard gravitational force law become evident at distances accessible to planned sub-mm gravity experiments. By examining the graviton decay contribution to the cosmic diffuse gamma radiation, we derive, for the case of two extra dimensions, a conservative bound M > 110TeV, corresponding to r{sub 2} < 5.1 x 10{sup -5} mm, well beyond the reach of these experiments. We also consider the constraint coming from graviton overclosure of the universe and derive an independent bound M > 6.5/{radical}h TeV, or r{sub 2} < .015hmm.

  5. Extra Dimensions and New Vector Bosons Searches in CMS

    SciTech Connect

    Emam, W.

    2008-04-21

    This paper addresses a series of searches for signals from extra dimensions and new vector bosons in the CMS experiment. A brief review of the CMS discovery potential of these signatures in different luminosity scenarios is presented.

  6. 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.

  7. 20 CFR 332.4 - Restrictions in extra service.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... gang service when there is in effect an arrangement between the employer and its employees for.... When the arrangement is such that an employee in extra board, pool, or chain gang service gets...

  8. 20 CFR 332.4 - Restrictions in extra service.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... gang service when there is in effect an arrangement between the employer and its employees for.... When the arrangement is such that an employee in extra board, pool, or chain gang service gets...

  9. 20 CFR 332.4 - Restrictions in extra service.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... gang service when there is in effect an arrangement between the employer and its employees for.... When the arrangement is such that an employee in extra board, pool, or chain gang service gets...

  10. 20 CFR 332.4 - Restrictions in extra service.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... gang service when there is in effect an arrangement between the employer and its employees for.... When the arrangement is such that an employee in extra board, pool, or chain gang service gets...

  11. 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

  12. Determing the Possible Building Blocks of the Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Burbine, T. H.

    2004-12-01

    One of the pioneers in the study of chondrites and planetary formation is John Wood. John has worked on a wide variety of subjects such as the condensation of chondritic material in the solar nebula and the heating sources that formed differentiated bodies. One unsolved question concerning planetary formation is exactly what material did the planets and asteroids form from. All the bodies in our solar system are believed to have formed out of material from the solar nebula. Chondritic meteorites appear to sample this primitive material. Detailed studies of the possible building blocks of the terrestrial planets and asteroids require samples that can be used to estimate the bulk chemistry of these planetary bodies. It appears very difficult to impossible to build the terrestrial planets out of a single type of chondritic meteorite. To try to determine possible building blocks of the terrestrial planets and asteroids, a computer program has been developed that inputs average oxygen isotopic values as well as average bulk chemical data for each chondritic group. Aggregate oxygen isotopic and bulk chemical compositions for every possible combination of these meteorites at mass increments of 5 percent were computed. Elements and compounds were combined linearly except for the oxygen isotopic values, which were weighted by the oxygen content of each meteorite. Redox reactions were used to determine the FeO content of each matching combination. Over 225 million combinations of the thirteen meteorite groups are produced. The bulk oxygen isotopic and chemical chemistries of the combinations can then be compared to those of any planet or asteroid. This modeling shows that it is extremely difficult to form the Earth out of known chondrites, but much easier to form Mars. This method will be used to determine possible chondritic precursors of differentiated asteroids such as the angrite and the basaltic achondrite parent bodies. Samples from Mercury and Venus are needed to

  13. 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.

  14. 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.

  15. Long Term Evolution of the Terrestrial Planets' Spin Axes

    NASA Astrophysics Data System (ADS)

    Laskar, J.

    2004-05-01

    The long term evolution of the spin axis of the terrestrial planets strongly depends on the gravitational perturbations from all the planets of the Solar System that create a large chaotic zone for their obliquity. Over the age of the Solar System, it is also necessary to take into account various dissipative effects that are usually not very well known (body and atmospheric tides, core-mantle friction), and that can change in a large amount the spin rate and orientation of the planet. In this talk, I will review the recent studies that we conducted on all Terrestrial planets (Mercury, Venus, Earth, and Mars), in order to better understand their spin evolution over the age of the Solar System. Acknowledgement: This study benefited from support from PNP-CNRS, IDRIS-CNRS, and CS, Paris Observatory.

  16. 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.

  17. Extra-abdominal desmoid tumors associated with familial adenomatous polyposis.

    PubMed

    Calvert, George T; Monument, Michael J; Burt, Randall W; Jones, Kevin B; Randall, R Lor

    2012-01-01

    Extra-abdominal desmoid tumors are a significant cause of morbidity in patients with familial adenomatous polyposis syndrome. Understanding of the basic biology and natural history of these tumors has increased substantially over the past decade. Accordingly, medical and surgical management of desmoid tumors has also evolved. This paper analyzes recent evidence pertaining to the epidemiology, molecular biology, histopathology, screening, and treatment of extra-abdominal desmoid tumors associated with familial adenomatous polyposis syndrome.

  18. Treatment of ankylosing spondylitis and extra-articular manifestations in everyday rheumatology practice.

    PubMed

    Elewaut, Dirk; Matucci-Cerinic, Marco

    2009-09-01

    The SpAs are a group of overlapping, chronic, inflammatory rheumatic diseases including AS, a chronic inflammatory disease primarily affecting the SI joints. In addition to inflammatory back pain, AS patients are also more likely to experience extra-articular manifestations belonging to the SpA concept which can affect the eyes, the gastrointestinal tract and the skin and other related inflammatory conditions. This review focuses on current progress in treatment options in SpA with special emphasis on extra-articular features. TNF inhibition has demonstrated effectiveness in the treatment of AS symptoms and all currently available anti-TNF agents appear to have similar efficacy. However, the efficacy of anti-TNF agents varies in the treatment of extra-articular manifestations and comorbidities. Analyses of trials of anti-TNF agents in patients with AS have revealed significant reductions in the incidence of flares of uveitis and IBD with infliximab and adalimumab (uveitis only) treatment but not with etanercept. All three anti-TNF agents (infliximab, adalimumab, etanercept) have demonstrated efficacy in psoriasis (not associated with AS). When evaluating as to which agent to use in the treatment of AS, an important consideration is the overall well-being of the patient. This should include any additional inflammatory burden that manifests in other parts of the body, which may currently be subclinical. Based on current evidence, among TNF inhibitors, the monoclonal antibodies (infliximab and adalimumab) are more appropriate than etanercept if extra-articular manifestations or comorbid conditions are present or suspected. To date, infliximab appears to be the best studied agent with a wide spectrum of proven efficacy.

  19. Moon and Terrestrial Planets: Unresolved Questions

    NASA Astrophysics Data System (ADS)

    Schmitt, H. H.

    2002-12-01

    . Additional unresolved questions raised by lunar exploration and study include 1) the effect of chondritic proto-cores on the timing of core formation in the terrestrial planets, 2) the number of extremely large basin-forming events (lunar diameters >2000 km) and the potential for proto-continents being formed by the differentiation of their melt sheets on water-rich planets, 3) effect of clays produced by the weathering of the debris and glass produced by pervasive asteroid and cometary impacts, 4) the many details of the differentiation of magma oceans, and 5) the processes governing the evolution of the lunar regolith. Finally, there is the question of when humans shall return to the Moon. On the one hand, the use of this unique and accessible planetary body as a scientific resource has barely begun. On the other hand, the Helium-3 fusion energy resources and deep space travel consumables that remain untapped in the lunar regolith hardly can be ignored in the face of human and environmental challenges on Earth and the species' desire to go to Mars. On both hands, it is time we took another walk on the Moon. 30 years going on 40 is long enough to think about what once was possible.

  20. Extra-Pair Mating and Evolution of Cooperative Neighbourhoods

    PubMed Central

    Eliassen, Sigrunn; Jørgensen, 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

  1. Factors influencing aquatic-to-terrestrial contaminant transport to terrestrial arthropod consumers in a multiuse river system.

    PubMed

    Alberts, Jeremy M; Sullivan, S Mažeika P

    2016-06-01

    Emerging aquatic insects are important vectors of contaminant transfer from aquatic to terrestrial food webs. However, the environmental factors that regulate contaminant body burdens in nearshore terrestrial consumers remain largely unexplored. We investigated the relative influences of riparian landscape composition (i.e., land use and nearshore vegetation structure) and contaminant flux via the emergent aquatic insect subsidy on selenium (Se) and mercury (Hg) body burdens of riparian ants (Formica subsericea) and spiders of the family Tetragnathidae along 11 river reaches spanning an urban-rural land-use gradient in Ohio, USA. Model-selection results indicated that fine-scale land cover (e.g., riparian zone width, shrub cover) in the riparian zone was positively associated with reach-wide body burdens of Se and Hg in both riparian F. subsericea and tetragnathid spiders (i.e., total magnitude of Hg and Se concentrations in ant and spider populations, respectively, for each reach). River distance downstream of Columbus, Ohio - where study reaches were impounded and flow through a large urban center - was also implicated as an important factor. Although stable-isotope analysis suggested that emergent aquatic insects were likely vectors of Se and Hg to tetragnathid spiders (but not to F. subsericea), emergent insect contaminant flux did not emerge as a significant predictor for either reach-wide body burdens of spider Hg or Se. Improved understanding of the pathways and influences that control aquatic-to-terrestrial contaminant transport will be critical for effective risk management and remediation. PMID:26874875

  2. 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.

  3. 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.

  4. Dietary characterization of terrestrial mammals.

    PubMed

    Pineda-Munoz, Silvia; Alroy, John

    2014-08-22

    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.

  5. 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.

  6. 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.

  7. 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

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

    PubMed

    Reid, Jane M; Duthie, A Bradley; Wolak, Matthew E; Arcese, Peter

    2015-07-01

    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

  9. 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...

  10. Bird terrestrial locomotion as revealed by 3D kinematics.

    PubMed

    Abourachid, Anick; Hackert, Remi; Herbin, Marc; Libourel, Paul A; Lambert, François; Gioanni, Henri; Provini, Pauline; Blazevic, Pierre; Hugel, Vincent

    2011-12-01

    Most birds use at least two modes of locomotion: flying and walking (terrestrial locomotion). Whereas the wings and tail are used for flying, the legs are mainly used for walking. The role of other body segments remains, however, poorly understood. In this study, we examine the kinematics of the head, the trunk, and the legs during terrestrial locomotion in the quail (Coturnix coturnix). Despite the trunk representing about 70% of the total body mass, its function in locomotion has received little scientific interest to date. This prompted us to focus on its role in terrestrial locomotion. We used high-speed video fluoroscopic recordings of quails walking at voluntary speeds on a trackway. Dorso-ventral and lateral views of the motion of the skeletal elements were recorded successively and reconstructed in three dimensions using a novel method based on the temporal synchronisation of both views. An analysis of the trajectories of the body parts and their coordination showed that the trunk plays an important role during walking. Moreover, two sub-systems participate in the gait kinematics: (i) the integrated 3D motion of the trunk and thighs allows for the adjustment of the path of the centre of mass; (ii) the motion of distal limbs transforms the alternating forward motion of the feet into a continuous forward motion at the knee and thus assures propulsion. Finally, head bobbing appears qualitatively synchronised to the movements of the trunk. An important role for the thigh muscles in generating the 3D motion of the trunk is suggested by an analysis of the pelvic anatomy. PMID:21982408

  11. 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.

  12. CT -- Body

    MedlinePlus

    ... News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Body Computed tomography (CT) of the body uses special x-ray ... Body? What is CT Scanning of the Body? Computed tomography, more commonly known as a CT or CAT ...

  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. 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.

  15. Phytopharmacological overview of Tribulus terrestris.

    PubMed

    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

  16. 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

  17. Methane production in terrestrial arthropods.

    PubMed

    Hackstein, J H; Stumm, C K

    1994-06-01

    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.

  18. 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

  19. 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.

  20. Toxic effects of acid rain on aquatic and terrestrial ecosystems.

    PubMed

    Rutherford, G K

    1984-08-01

    The historical perspective as well as the nature and causes of acid precipitation are presented. The toxicological effects of acid precipitation on lakes, other water bodies, fish, and invertebrate fauna are reviewed. In addition, the effects of this phenomenon on soil productivity and forest growth are examined. It appears that grave toxic effects have been and are being experienced by aquatic systems, but there is little reliable evidence of economic damage to crops, natural vegetation, and soil and biological processes. There may be insidious long-term effects on terrestrial ecosystems, particularly in the more susceptible areas.

  1. Oxygen Isotopes in the Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Clayton, R. N.

    2004-12-01

    Mechanisms that may account for oxygen isotope heterogeneity in meteorites on the microscopic scale do not seem adequate for explaining the similarities and differences in isotopic composition on a planetary scale. In chondrites, most of the isotopic variability can be attributed to photochemical enrichment of the two rare heavy isotopes with respect to the 16O-rich solar composition In the CO, CM, CI, and CR chondrites, an additional low-temperature aqueous alteration leads to mass-dependent further enrichment of the heavy isotopes. If the photochemical origin of the isotopic variation in chondrites is correct, then only a small fraction, represented primarily in CAIs, has the solar oxygen isotopic composition, and all other meteoritic components must have undergone photochemical processing. In addition, since the bulk isotopic compositions of the terrestrial planets and of the achondrite parent bodies are similar to those of chondrites, they too must be made of photochemically enriched matter. The photochemical reactions produce a non-equilibrium assemblage of gases, probably leading to a non-equilibrium assemblage of solids, particularly with respect to their oxidation state. These issues emphasize the importance of the measurement of oxygen isotopes in the Genesis solar wind mission. Within the Earth, oxygen isotope variations are due almost entirely to mass-dependent fractionation effects, giving a line of slope 0.52 on the three-isotope plot. The average crustal composition is 3 to 4 permil higher in delta-18O than the upper mantle. This difference is too large to be due to igneous fractionation effects alone, and reflects the larger, low-temperature isotope fractionation associated with aqueous weathering reactions at the Earth's surface. Similar effects are not observed in the intraplanetary isotopic variations in the Moon or in the parent bodies of the HED and SNC meteorites. The bulk oxygen isotopic compositions of Earth and Mars (assumed to be the SNC

  2. 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.

  3. Probing Terrestrial Planet Formation with Extreme Disk Variability

    NASA Astrophysics Data System (ADS)

    Su, Kate; Rieke, George; Gaspar, Andras; Jackson, Alan

    2016-08-01

    Spitzer has advanced our knowledge about the critical stages of terrestrial planet formation (and in some cases destruction) by discovering young stars orbited by 1.) silica dust emission close to their terrestrial zones indicative of the violent collisions, and 2.) variable disk emission arising from the aftermath of asteroid-size impacts. The variable emission provides a unique opportunity to learn about asteroid-sized bodies in young exoplanetary systems and to explore planetesimal collisions and their aftermaths during the era of terrestrial-planet-building. We propose continued study of debris disk variability, focused in two areas: (1) to provide continuous monitoring of systems where our existing program has discovered substantial variations indicative of major ongoing episodes of planetesimal impacts; and (2) to investigate intensively possible variations in the dust content of systems that show prominent crystalline emission features to establish a link between the two indicators of planet building. Together these objectives will prepare us for the JWST era, when we will again obtain mid-infrared spectra of these systems, and of both higher spectral resolution and signal to noise than has been possible previously. This program will extend the time-domain study of extreme debris disks as an important heritage of the Spitzer warm mission.

  4. The effects of circumstellar gas on terrestrial planet formation: Theory and observation

    NASA Astrophysics Data System (ADS)

    Mandell, Avram M.

    Our understanding of the evolution of circumstellar material from dust and gas to fully-formed planets has taken dramatic steps forward in the last decade, driven by rapid improvements in our ability to study gas- and dust-rich disks around young stars and the discovery of more than 200 extra-solar planetary systems around other stars. In addition, our ability to model the formation of both terrestrial and giant planets has improved significantly due to new computing techniques and the continued exponential increase in computing power. In this dissertation I expand on existing theories of terrestrial planet formation to include systems similar to those currently being detected around nearby stars, and I develop new observational techniques to probe the chemistry of gas-rich circumstellar disks where such planetary systems may be forming. One of the most significant characteristics of observed extrasolar planetary systems is the presence of giant planets located much closer to their parent star than was thought to be possible. The presence of "Hot Jupiters", Jovian-mass planets with very short orbital periods detected around nearby main sequence stars, has been proposed to be primarily due to the inward migration of planets formed in orbits initially much further from the parent star. Close-in giant planets are thought to have formed in the cold outer regions of planetary systems and migrated inward, passing through the orbital parameter space occupied by the terrestrial planets in our own Solar System; the migration of these planets would have profound effects on the evolution of inner terrestrial planets in these systems. I first explore this scenario with numerical simulations showing that a significant fraction of terrestrial planets could survive the migration process; damping forces could then eventually re-circularize the orbits at distances relatively close to their original positions. Calculations suggest that the final orbits of a significant fraction of

  5. 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.

  6. Terrestrial ecosystems in a changing environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transpiration—the movement of water from the soil, through plants, and into the atmosphere—is the dominant water flux from the earth’s terrestrial surface. The evolution of vascular plants, while increasing terrestrial primary productivity, led to higher transpiration rates and widespread alteration...

  7. Use of ICS/LABA (extra-fine and non-extra-fine) in elderly asthmatics

    PubMed Central

    Benfante, Alida; Basile, Marco; Battaglia, Salvatore; Spatafora, Mario; Scichilone, Nicola

    2016-01-01

    Age represents an exclusion criterion in randomized clinical trials designed to test the efficacy and safety of inhaled drugs in asthma. As a consequence, data on efficacy and safety of inhaled corticosteroid (ICS) and long-acting β2 agonist (LABA) combinations in elderly asthmatics are scanty. Older age is associated with an increased proportion of comorbid conditions; in addition, all organ functions undergo a process of senescence, thus reducing their ability to metabolize the agents. Overall, these age-associated conditions may variably, and often unpredictably, affect the metabolism and excretion of respiratory drugs. However, pharmacological treatment of asthma does not follow specific recommendations in the elderly. In the elderly, the ICS/LABA combinations may carry an increased risk of local indesiderable effects, primarily due to the lack of coordination between activation of the device and inhalation, and systemic adverse events, mainly due to the greater amount of active drug that is available because of the age-associated changes in organ functions as well as drug-to-drug and drug-to-concomitant disease interactions. The extra-fine formulations of ICSs/LABAs, which allow for a more favorable drug deposition in the lungs at a reduced dose, may contribute to overcome this issue. This review revises the efficacy and safety of treatment with ICSs/LABAs, focusing on the main pharmacodynamic and pharmacokinetic properties of the drugs and highlighting the potential risks in the elderly asthmatic population. PMID:27789954

  8. 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.…

  9. 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

  10. 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

  11. 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.

  12. Nonminimal universal extra dimensional model confronts Bs→μ+μ-

    NASA Astrophysics Data System (ADS)

    Datta, Anindya; Shaw, Avirup

    2016-03-01

    The addition of boundary localized kinetic and Yukawa terms to the action of a five-dimensional Standard Model would nontrivially modify the Kaluza-Klein spectra and some of the interactions among the Kaluza-Klein excitations compared to the minimal version of this model, in which these boundary terms are not present. In the minimal version of this framework, known as the universal extra dimensional model, special assumptions are made about these unknown, beyond the cutoff contributions to restrict the number of unknown parameters of the theory to be minimum. We estimate the contribution of Kaluza-Klein modes to the branching ratios of Bs (d )→μ+μ- in the framework of the nonminimal universal extra dimensional model, at one-loop level. The results have been compared to the experimental data to constrain the parameters of this model. From the measured decay branching ratio of Bs→μ+μ- (depending on the values of boundary localized parameters), the lower limit on R-1 can be as high as 800 GeV. We have briefly reviewed the bounds on nonminimal universal extra dimensional parameter space coming from electroweak precision observables. The present analysis (Bs→μ+μ-) has ruled out new regions of parameter space in comparison to the analysis of electroweak data. We have revisited the bound on R-1 in the universal extra dimensional model, which came out to be 454 GeV. This limit on R-1 in the universal extra dimensional framework is not as competitive as the limits derived from the consideration of relic density or Standard Model Higgs boson production and decay to W+W-. Unfortunately, the Bd→μ+μ- decay branching ratio would not set any significant limit on R-1 in a minimal or nonminimal universal extra dimensional model.

  13. Resource subsidies between stream and terrestrial ecosystems under global change

    USGS Publications Warehouse

    Larsen, Stefano; Muehlbauer, Jeffrey D.; Marti Roca, Maria Eugenia

    2016-01-01

    Streams and adjacent terrestrial ecosystems are characterized by permeable boundaries that are crossed by resource subsidies. Although the importance of these subsidies for riverine ecosystems is increasingly recognized, little is known about how they may be influenced by global environmental change. Drawing from available evidence, in this review we propose a conceptual framework to evaluate the effects of global change on the quality and spatiotemporal dynamics of stream–terrestrial subsidies. We illustrate how changes to hydrological and temperature regimes, atmospheric CO2 concentration, land use and the distribution of nonindigenous species can influence subsidy fluxes by affecting the biology and ecology of donor and recipient systems and the physical characteristics of stream–riparian boundaries. Climate-driven changes in the physiology and phenology of organisms with complex life cycles will influence their development time, body size and emergence patterns, with consequences for adjacent terrestrial consumers. Also, novel species interactions can modify subsidy dynamics via complex bottom-up and top-down effects. Given the seasonality and pulsed nature of subsidies, alterations of the temporal and spatial synchrony of resource availability to consumers across ecosystems are likely to result in ecological mismatches that can scale up from individual responses, to communities, to ecosystems. Similarly, altered hydrology, temperature, CO2 concentration and land use will modify the recruitment and quality of riparian vegetation, the timing of leaf abscission and the establishment of invasive riparian species. Along with morphological changes to stream–terrestrial boundaries, these will alter the use and fluxes of allochthonous subsidies associated with stream ecosystems. Future research should aim to understand how subsidy dynamics will be affected by key drivers of global change, including agricultural intensification, increasing water use and biotic

  14. Resource subsidies between stream and terrestrial ecosystems under global change.

    PubMed

    Larsen, Stefano; Muehlbauer, Jeffrey D; Marti, Eugenia

    2016-07-01

    Streams and adjacent terrestrial ecosystems are characterized by permeable boundaries that are crossed by resource subsidies. Although the importance of these subsidies for riverine ecosystems is increasingly recognized, little is known about how they may be influenced by global environmental change. Drawing from available evidence, in this review we propose a conceptual framework to evaluate the effects of global change on the quality and spatiotemporal dynamics of stream-terrestrial subsidies. We illustrate how changes to hydrological and temperature regimes, atmospheric CO2 concentration, land use and the distribution of nonindigenous species can influence subsidy fluxes by affecting the biology and ecology of donor and recipient systems and the physical characteristics of stream-riparian boundaries. Climate-driven changes in the physiology and phenology of organisms with complex life cycles will influence their development time, body size and emergence patterns, with consequences for adjacent terrestrial consumers. Also, novel species interactions can modify subsidy dynamics via complex bottom-up and top-down effects. Given the seasonality and pulsed nature of subsidies, alterations of the temporal and spatial synchrony of resource availability to consumers across ecosystems are likely to result in ecological mismatches that can scale up from individual responses, to communities, to ecosystems. Similarly, altered hydrology, temperature, CO2 concentration and land use will modify the recruitment and quality of riparian vegetation, the timing of leaf abscission and the establishment of invasive riparian species. Along with morphological changes to stream-terrestrial boundaries, these will alter the use and fluxes of allochthonous subsidies associated with stream ecosystems. Future research should aim to understand how subsidy dynamics will be affected by key drivers of global change, including agricultural intensification, increasing water use and biotic

  15. 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…

  16. 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)

  17. Search for Universal Extra Dimensions with the D0 Experiment

    SciTech Connect

    Mansour, Jason D.

    2011-10-01

    A search for signs of universal extra dimensions (UED) has been performed with the D0 experiment, using events with two same-sign muons. The considered minimal UED model includes one extra dimension, and has a stable lightest Kaluza-Klein particle (LKP) which is a dark matter candidate. In the search, 7.3 fb{sup -1} of D0 data, collected in p{bar p} collisions at the Fermilab Tevatron collider at {radical}s = 1.96 TeV, have been used.

  18. Scrotal abscess, a rare case of extra intestinal amoebiasis.

    PubMed

    Prasetyo, R H

    2015-09-01

    The majority of amoeba infection are asymptomatic, but clinically intestinal amoebiasis or extra intestinal amoebiasis may result. Genital amoebiasis is very rare manifestation of extra intestial amoebiasis, but a case of amoebic scrotal abscess, seen in Surabaya. The invasive form of Entamoeba histolytica trophozoite was seen in Giemsa stained aspirate of the abscess. In case of an abscess bacteria are primarly considered, but the case presented here shows that amoeba can be the cause, although very rarely. Thus when bacteriological diagnostics are negative amoeba should be considered, especially in case of brown-reddish colored and foul smelling pus. PMID:26695210

  19. Universal Extra Dimension models with right-handed neutrinos

    SciTech Connect

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

    2008-04-21

    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.

  20. Inheritance contradictions between functional and extra-functional requirements

    SciTech Connect

    Hochmueller, E.

    1996-12-31

    This paper discusses the tension which may arise between functional and extra-functional requirements during the process of object-oriented design. A sketch of some design conflicts in object-oriented development induced by concurrency and security requirements will serve as a basis for rather provocative prospects on an essential distinction between the core requirements for systems dealing with their proper purpose and functionality and the requirements which can be considered to be of extra-functional nature in constraining the systems solution space.

  1. 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.

  2. 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.

  3. Thrash, flip, or jump: the behavioral and functional continuum of terrestrial locomotion in teleost fishes.

    PubMed

    Gibb, Alice C; Ashley-Ross, Miriam A; Hsieh, S Tonia

    2013-08-01

    Moving on land versus in water imposes dramatically different requirements on the musculoskeletal system. Although many limbed vertebrates, such as salamanders and prehistoric tetrapodomorphs, have an axial system specialized for aquatic locomotion and an appendicular system adapted for terrestrial locomotion, diverse extant teleosts use the axial musculoskeletal system (body plus caudal fin) to move in these two physically disparate environments. In fact, teleost fishes living at the water's edge demonstrate diversity in natural history that is reflected in a variety of terrestrial behaviors: (1) species that have only incidental contact with land (such as largemouth bass, Micropterus) will repeatedly thrash, which can roll an individual downhill, but cannot produce effective overland movements, (2) species that have occasional contact with land (like Gambusia, the mosquitofish, which evade predators by stranding themselves) will produce directed terrestrial movement via a tail-flip jump, and (3) species that spend more than half of their lives on land (like the mudskipper, Periopthalmus) will produce a prone-jump, a behavior that allows the fish to anticipate where it will land at the end of the flight phase. Both tail-flip and prone jumps are characterized by a two-phase movement consisting of body flexion followed by extension-a movement pattern that is markedly similar to the aquatic fast-start. Convergence in kinematic pattern between effective terrestrial behaviors and aquatic fast starts suggests that jumps are an exaptation of a neuromuscular system that powers unsteady escape behaviors in the water. Despite such evidence that terrestrial behaviors evolved from an ancestral behavior that is ubiquitous among teleosts, some teleosts are unable to move effectively on land-possibly due to morphological trade-offs, wherein specialization for one environment comes at a cost to performance in the other. Indeed, upon emergence onto land, gravity places an

  4. Thrash, flip, or jump: the behavioral and functional continuum of terrestrial locomotion in teleost fishes.

    PubMed

    Gibb, Alice C; Ashley-Ross, Miriam A; Hsieh, S Tonia

    2013-08-01

    Moving on land versus in water imposes dramatically different requirements on the musculoskeletal system. Although many limbed vertebrates, such as salamanders and prehistoric tetrapodomorphs, have an axial system specialized for aquatic locomotion and an appendicular system adapted for terrestrial locomotion, diverse extant teleosts use the axial musculoskeletal system (body plus caudal fin) to move in these two physically disparate environments. In fact, teleost fishes living at the water's edge demonstrate diversity in natural history that is reflected in a variety of terrestrial behaviors: (1) species that have only incidental contact with land (such as largemouth bass, Micropterus) will repeatedly thrash, which can roll an individual downhill, but cannot produce effective overland movements, (2) species that have occasional contact with land (like Gambusia, the mosquitofish, which evade predators by stranding themselves) will produce directed terrestrial movement via a tail-flip jump, and (3) species that spend more than half of their lives on land (like the mudskipper, Periopthalmus) will produce a prone-jump, a behavior that allows the fish to anticipate where it will land at the end of the flight phase. Both tail-flip and prone jumps are characterized by a two-phase movement consisting of body flexion followed by extension-a movement pattern that is markedly similar to the aquatic fast-start. Convergence in kinematic pattern between effective terrestrial behaviors and aquatic fast starts suggests that jumps are an exaptation of a neuromuscular system that powers unsteady escape behaviors in the water. Despite such evidence that terrestrial behaviors evolved from an ancestral behavior that is ubiquitous among teleosts, some teleosts are unable to move effectively on land-possibly due to morphological trade-offs, wherein specialization for one environment comes at a cost to performance in the other. Indeed, upon emergence onto land, gravity places an

  5. 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

  6. 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.

  7. 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

  8. 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

  9. Confirmation and distribution of tetrodotoxin for the first time in terrestrial invertebrates: two terrestrial flatworm species (Bipalium adventitium and Bipalium kewense).

    PubMed

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

  10. 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.

  11. 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.

  12. Steroidal saponins from Tribulus terrestris.

    PubMed

    Kang, Li-Ping; Wu, Ke-Lei; Yu, He-Shui; Pang, Xu; Liu, Jie; Han, Li-Feng; Zhang, Jie; Zhao, Yang; Xiong, Cheng-Qi; Song, Xin-Bo; Liu, Chao; Cong, Yu-Wen; Ma, Bai-Ping

    2014-11-01

    Sixteen steroidal saponins, including seven previously unreported compounds, were isolated from Tribulus terrestris. The structures of the saponins were established using 1D and 2D NMR spectroscopy, mass spectrometry, and chemical methods. They were identified as: 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-2α,3β,22α,26-tetrol-12-one (terrestrinin C), 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-22α,26-diol-3,12-dione (terrestrinin D), 26-O-β-d-glucopyranosyl-(25S)-furost-4-en-22α,26-diol-3,6,12-trione (terrestrinin E), 26-O-β-d-glucopyranosyl-(25R)-5α-furostan-3β,22α,26-triol-12-one (terrestrinin F), 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-12β,22α,26-triol-3-one (terrestrinin G), 26-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl-(25R)-furost-4-en-22α,26-diol-3,12-dione (terrestrinin H), and 24-O-β-d-glucopyranosyl-(25S)-5α-spirostan-3β,24β-diol-12-one-3-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranoside (terrestrinin I). The isolated compounds were evaluated for their platelet aggregation activities. Three of the known saponins exhibited strong effects on the induction of platelet aggregation.

  13. Steroidal saponins from Tribulus terrestris.

    PubMed

    Su, Lan; Chen, Gang; Feng, Sheng-Guang; Wang, Wei; Li, Zhi-Feng; Chen, Huan; Liu, Ying-Xue; Pei, Yue-Hu

    2009-01-01

    Five new steroidal saponins were isolated from the fruits of Tribulus terrestris. Their structures were fully established by spectroscopic and chemical analysis as (23S,25S)-5alpha-spirostane-24-one-3beta,23-diol-3-O-{alpha-l-rhamnopyranosyl-(1-->2)-O-[beta-d-glucopyranosyl-(1-->4)]-beta-d-galactopyranoside} (1), (24S,25S)-5alpha-spirostane-3beta,24-diol-3-O-{alpha-l-rhamnopyranosyl-(1-->2)-O-[beta-d-glucopyranosyl-(1-->4)]-beta-d-galactopyranoside} (2), 26-O-beta-d-glucopyranosyl-(25R)-5alpha-furostan-2alpha,3beta,22alpha,26-tetraol-3-O-{beta-d-glucopyranosyl-(1-->2)-O-beta-d-glucopyranosyl-(1-->4)-beta-d-galactopyranoside} (3), 26-O-beta-d-glucopyranosyl-(25R)-5alpha-furostan-20(22)-en-2alpha,3beta,26-triol-3-O-{beta-d-glucopyranosyl-(1-->2)-O-beta-d-glucopyranosyl-(1-->4)-beta-d-galactopyranoside} (4), and 26-O-beta-d-glucopyranosyl-(25S)-5alpha-furostan-12-one-22-methoxy-3beta,26-diol-3-O-{alpha-l-rhamnopyranosyl-(1-->2)-O-[beta-d-glucopyranosyl-(1-->4)]-beta-d-galactopyranoside} (5). The isolated compounds were evaluated for cytostatic activity against HL-60 cells.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Energetics of metamorphic climax in the southern toad (Bufo terrestris).

    PubMed

    Beck, Christopher W; Congdon, Justin D

    2003-11-01

    During metamorphic climax, anuran larvae must rely on stored energy because changes in oral and digestive morphology prevent foraging and efficient assimilation. Thus, the time required to store adequate energy for metamorphic climax may set a lower limit on age at which it can occur. Therefore, the amount and type of energy used during metamorphic climax must be determined. To quantify the energetic costs of metamorphic climax in Bufo terrestris, oxygen consumption during climax was measured. Wet mass, dry mass, and lipid mass for a group of individuals at the initiation of climax (forelimb emergence, FL) and for another group at the end of climax (complete tail resorption, TR) were also measured to determine whether lipids were used to fuel metamorphic climax. The total amount of energy used, maintenance costs, and development costs during metamorphic climax varied considerably among individuals. Variation in energy metabolism during climax was not related to differences in energy metabolism during larval development or body mass at initiation of climax. TR individuals were significantly lighter in terms of wet mass and had less body water than FL individuals. However, the two groups did not differ in dry mass or lipid mass. Therefore, lipid catabolism is not a major source of energy during metamorphic climax in B. terrestris. As a result, decreases in age at metamorphosis may not be constrained by the need to store energy in the form of lipids.

  20. 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

  1. 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

  2. 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

  3. Results of extremely low birth weight infants randomized to receive extra enteral calcium supply

    PubMed Central

    Carroll, William F.; Fabres, Jorge; Nagy, Tim R.; Frazier, Marcela; Roane, Claire; Pohlandt, Frank; Carlo, Waldemar A.; Thome, Ulrich H.

    2011-01-01

    Background Bone mineral deficiency continues to occur in extremely low birth weight (ELBW) infants despite formulas enriched in Ca and P. Objective This study tested whether extra enteral Ca supplementation increases bone mineral content (BMC) and prevents dolichocephalic head flattening and myopia in ELBW infants. Study design Infants 401–1000 birth weight receiving enteral feeds were randomized to receive feeds supplemented with Ca-gluconate powder, or pure standard feeds. Main outcome measures were the excretion of Ca and P by weekly spot urine measurements, the degree of dolichocephalic deformation (fronto-occipital to biparietal diameter ratio, FOD/BPD) at 36 weeks postmenstrual age and the BMC (by dual-energy x-ray absorptiometry) at discharge. Cycloplegic refraction was measured at 18–22 months corrected age. Results Ninety-nine ELBW infants with a gestational age of 26 weeks (23–31) [Median (minimum-maximum)] were randomized at a postnatal age of 12 days (5–23) weighing 790g (440–1700). Urinary Ca excretion increased, P excretion decreased in the Ca supplemented group. Total body BMC was 89.9 ± 2.4 g (mean ± SE) in the supplemented group and 85.2 ± 2.6 g in the control group (p= 0.19). The FOD/BPD was 1.50 (1.13–1.69, mean ± SD) and 1.47 (1.18–1.64) in the supplemented and control groups, and the refraction 0.98 ± 1.23 and 1.40 ± 1.33 dpt. (p=0.68), respectively in 64 ELBW infants (79% of survivors) at 2-year-follow-up. Conclusions Extra enteral Ca supplementation did not change BMC, head shape or refraction. The decreased P excretion may reflect P deficiency in infants receiving extra Ca, preventing improved bone mineral accretion. PMID:21865980

  4. 32 CFR 776.45 - Extra-tribunal statements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Extra-tribunal statements. 776.45 Section 776.45 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY MISCELLANEOUS RULES PROFESSIONAL... possibility of a plea of guilty to the offense or the existence or contents of any confession, admission,...

  5. 32 CFR 776.45 - Extra-tribunal statements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 5 2013-07-01 2013-07-01 false Extra-tribunal statements. 776.45 Section 776.45 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY MISCELLANEOUS RULES PROFESSIONAL... possibility of a plea of guilty to the offense or the existence or contents of any confession, admission,...

  6. 32 CFR 776.45 - Extra-tribunal statements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Extra-tribunal statements. 776.45 Section 776.45 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY MISCELLANEOUS RULES PROFESSIONAL... possibility of a plea of guilty to the offense or the existence or contents of any confession, admission,...

  7. 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…

  8. Attitude Strength: An Extra-Content Aspect of Attitude.

    ERIC Educational Resources Information Center

    Alwitt, Linda F.

    Attitude strength is considered as an extra-content aspect of attitude. A model of the relationship of attitude strength to attitude direction and behavior proposes that attitude strength is comprised of three dimensions that moderate the relationship between attitude direction and behavior. The dimensions are parallel to the tripartite dimensions…

  9. 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

  10. 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

  11. Extra-axial isolated cerebral varix misdiagnosed as convexity meningioma

    PubMed Central

    Tan, Zhi-Gang; Zhou, Qian; Cui, Yan; Yi, Lei; Ouyang, Yian; Jiang, Yugang

    2016-01-01

    Abstract Isolated cerebral varix is a rare cerebrovascular anomaly, which is easily misdiagnosed as other brain tumors. A 59-year-old female patient with noncontributory medical history presented with headache and insomnia for the last 2 months. Upon admission, her neurological examination was unremarkable. Magnetic resonance imaging revealed a well-demarcated extra medullary mass, 11 × 11 mm in size, within the subdural space at the right frontal lobe. The lesion was initially interpreted as a convexity meningioma. After conducting a craniotomy on the patient, an extra-axial varix was exposed and resected subsequently. The patient's headache was resolved soon after surgery and charged without neurologic sequelae. Extra-axial isolated cerebral varix is mimicking convexity meningioma on MR images and should be considered as a differential diagnosis. The focal erosion in the inner table of the skull could be an important character of extra-axial isolated cerebral varix. An extremely round shape and smooth contour of the lesion was another important character. Isolated cerebral varix is rare vascular lesion that is treated surgically in the case of rupture or compression of adjacent structures. The information obtained with noninvasive imaging techniques should include CTA to make a clinical decision. PMID:27368037

  12. 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…

  13. 20 CFR 332.4 - Restrictions in extra service.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Restrictions in extra service. 332.4 Section 332.4 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT MILEAGE OR WORK RESTRICTIONS AND STAND-BY OR LAY-OVER RULES § 332.4 Restrictions in...

  14. Extra-articular Mimickers of Lateral Meniscal Tears

    PubMed Central

    Barker, Joseph U.; Strauss, Eric J.; Lodha, Sameer; Bach, Bernard R.

    2011-01-01

    Context: Lateral meniscus tears are a common entity seen in sports medicine. Although lateral-side knee pain is often the result of a meniscus injury, several extra-articular pathologies share signs and symptoms with a meniscus tear. It is critical for the clinician to be able to identify and understand extra-articular pathologies that can present similar to a lateral meniscus tear. Evidence Acquisition: Data were collected through a thorough review of the literature conducted through a MEDLINE search for all relevant articles between 1980 and February 2010. Study Type: Clinical review. Results: Common extra-articular pathologies that can mimic lateral meniscal tears include iliotibial band syndrome, proximal tibiofibular joint instability, snapping biceps femoris or popliteus tendons, and peroneal nerve compression syndrome or neuritis. The patient history, physical examination features, and radiographic findings can be used to separate these entities from the more common intra-articular knee pathologies. Conclusions: In treating patients who present with lateral-sided knee pain, clinicians should be able to recognize and treat extra-articular pathologies that can present in a similar fashion as lateral meniscus tears. PMID:23015995

  15. The use of extra-oral traction with removable appliances.

    PubMed

    Rock, W P

    1990-05-19

    Extra-oral traction has two main applications in orthodontic treatment. It may be used to prevent forward movement of anchor teeth and also to provide a force for distalisation of molars, and/or buccal segments. If correctly applied, EOT can help to ease problems in a difficult treatment and make possible an otherwise impossible treatment plan.

  16. 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…

  17. Estimating the extra cost of living with disability in Vietnam.

    PubMed

    Minh, Hoang Van; Giang, Kim Bao; Liem, Nguyen Thanh; Palmer, Michael; Thao, Nguyen Phuong; Duong, Le Bach

    2015-01-01

    Disability is shown to be both a cause and a consequence of poverty. However, relatively little research has investigated the economic cost of living with a disability. This study reports the results of a study on the extra cost of living with disability in Vietnam in 2011. The study was carried out in eight cities/provinces in Vietnam, including Hanoi and Ho Chi Minh cities (two major metropolitan in Vietnam) and six provinces from each of the six socio-economic regions in Vietnam. Costs are estimated using the standard of living approach whereby the difference in incomes between people with disability and those without disability for a given standard of living serves as a proxy for the cost of living with disability. The extra cost of living with disability in Vietnam accounted for about 8.8-9.5% of annual household income, or valued about US$200-218. Communication difficulty was shown to result in highest additional cost of living with disability and self-care difficulty was shown to lead to the lowest levels of extra of living cost. The extra cost of living with disability increased as people had more severe impairment. Interventions to promote the economic security of livelihood for people with disabilities are needed.

  18. Extra focal convective suppressing solar collector. Final technical progress report

    SciTech Connect

    1996-05-01

    This progress report describes work done on the Extra Focal Convective Suppressing Solar Collector. The topics of the report include sensor refinement for the tracking electronics, tracking controller refinement, system optics evaluation, absorber system material evaluation and performance, tracking hardware evaluation and refinement, and full scale prototype construction and testing.

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

    PubMed

    Gharby, Saïd; 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.

  20. 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…

  1. 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.

  2. Extra-medical stimulant dependence among recent initiates

    PubMed Central

    O’Brien, Megan S.; Anthony, James C.

    2014-01-01

    New estimates for the risk of becoming stimulant dependent within 24 months after first extra-medical (EM) use of a stimulant drug compound are presented, with a focus on subgroup variations in this risk (e.g., alcohol dependence, male–female differences). The study estimates are derived from a representative sample of United States residents ages 12 and older (n = 166,737) obtained from the 2003 to 2005 National Surveys on Drug Use and Health. A total of 1700 respondents were found to have used stimulants extra-medically for the first time within 24 months prior to assessment. Approximately 5% of these recent-onset EM users had become stimulant dependent since onset of EM use. As hypothesized, alcohol dependence cases were found to have experienced an excess risk of becoming stimulant dependent soon after onset of stimulant drug use; there was no robust male–female difference in risk. Independently, initiates who had used multiple types of stimulants extra-medically, and methamphetamine users, were more likely to have become stimulant dependent soon after onset of use; by comparison, EM users of methylphenidate (Ritalin®) were less likely to have developed rapid-onset dependence. These epidemiologic findings help quantify a continuing public health burden associated with new onsets of extra-medical stimulant use in the 21st century. PMID:19515516

  3. Deviations from Newton's law in supersymmetric large extra dimensions

    NASA Astrophysics Data System (ADS)

    Callin, P.; Burgess, C. P.

    2006-09-01

    Deviations from Newton's inverse-squared law at the micron length scale are smoking-gun signals for models containing supersymmetric large extra dimensions (SLEDs), which have been proposed as approaches for resolving the cosmological constant problem. Just like their non-supersymmetric counterparts, SLED models predict gravity to deviate from the inverse-square law because of the advent of new dimensions at sub-millimeter scales. However SLED models differ from their non-supersymmetric counterparts in three important ways: (i) the size of the extra dimensions is fixed by the observed value of the dark energy density, making it impossible to shorten the range over which new deviations from Newton's law must be seen; (ii) supersymmetry predicts there to be more fields in the extra dimensions than just gravity, implying different types of couplings to matter and the possibility of repulsive as well as attractive interactions; and (iii) the same mechanism which is purported to keep the cosmological constant naturally small also keeps the extra-dimensional moduli effectively massless, leading to deviations from general relativity in the far infrared of the scalar-tensor form. We here explore the deviations from Newton's law which are predicted over micron distances, and show the ways in which they differ and resemble those in the non-supersymmetric case.

  4. 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…

  5. 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…

  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. [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.

  8. 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.

  9. 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.

  10. 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.

  11. Search for large extra dimensions in diphoton events at CDF

    NASA Astrophysics Data System (ADS)

    Murgia, Simona

    In spite of its undisputed success, the Standard Model is not a theory of everything as it does not incorporate gravity. Gravity is the weakest of all forces and its strength becomes comparable to the remaining forces at energies of the order of the Planck scale, at approximately 10 19 GeV and the Standard Model is viewed as an effective theory at energies below this scale. Recently, a model of large extra dimensions has been formulated by Arkani-Hamed, Dimopoulous, and Dvali that claims that the electroweak scale (approximately 1 TeV) is the only fundamental scale in nature and the fact that the Planck scale appears so large is an artifact of the existence of extra dimensions in which only gravity propagates. This theory can be tested at existing collider experiments, where energies sufficiently high to probe the extra dimensions can be achieved. In particular, the existence of extra dimensions can manifest itself with production of Standard Model particles through graviton mediated processes and thus it predicts an enhancement of production cross sections at high invariant mass. The goal of this work is to search for an excess in the 100 pb-1 of diphoton data collected with the Collider Detector at Fermilab at s = 1.8 TeV during the 1992--1996 run. No excess is observed and thus we place a 95% confidence level limit on the Planck scale in the bulk extra dimensions MS of 899 GeV for constructive interference and of 797 GeV for destructive interference (Hewett convention).

  12. 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.

  13. 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

  14. Terrestrial analogs of the hellespontus dunes, Mars

    USGS Publications Warehouse

    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. ?? 1977.

  15. 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.

  16. Carbon dioxide sequestration in terrestrial ecosystems

    SciTech Connect

    Wisniewski, J.; Dixon, R.K.; Kinsman, J.D.; Sampson, R.N.; Lugo, A.E.

    1993-01-01

    The terrestrial biosphere plays a prominent role in the global carbon (C) cycle. Terrestrial ecosystems are currently accumulating C and it appears feasible to manage existing terrestrial (forest, agronomic, desert) ecosystems to maintain or increase C storage. Forest ecosystems can be managed to sequester and store globally significant amounts of C. Agroecosystems and arid lands could be managed to conserve existing terrestrial C but CO2 sequestration rates by vegetation in these systems is relatively low. Biomass from forest agroecosystems has the potential to be used as an energy source and trees could be used to conserve energy in urban environments. Some ecosystem management practices that result in C sequestration and conservation provide ancillary benefits.

  17. Transfer of terrestrial technology for lunar mining

    NASA Technical Reports Server (NTRS)

    Hall, Robert A.; Green, Patricia A.

    1992-01-01

    The functions, operational procedures, and major items of equipment that comprise the terrestrial mining process are characterized. These data are used to synthesize a similar activity on the lunar surface. Functions, operations, and types of equipment that can be suitably transferred to lunar operation are identified. Shortfalls, enhancements, and technology development needs are described. The lunar mining process and what is required to adapt terrestrial equipment are highlighted. It is concluded that translation of terrestrial mining equipment and operational processes to perform similar functions on the lunar surface is practical. Adequate attention must be given to the harsh environment and logistical constraints of the lunar setting. By using earth-based equipment as a forcing function, near- and long-term benefits are derived (i.e., improved terrestrial mining in the near term vis-a-vis commercial production of helium-3 in the long term.

  18. 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.

  19. 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.

  20. The influence of terrestrial ecosystems on climate.

    PubMed

    Meir, Patrick; Cox, Peter; Grace, John

    2006-05-01

    Terrestrial ecosystems influence climate by affecting how much solar energy is absorbed by the land surface and by exchanging climatically important gases with the atmosphere. Recent model analyses show widespread qualitative agreement that terrestrial ecological processes will have a net positive feedback effect on 21st-century global warming, and, therefore, cannot be ignored in climate-change projections. However, the quantitative uncertainty in the net feedback is large. The uncertainty in 21st-century carbon dioxide emissions resulting from terrestrial carbon cycle-climate feedbacks is second in magnitude only to the uncertainty in anthropogenic emissions. We estimate that this translates into an uncertainty in global warming owing to the land surface of 1.5 degrees C by 2100. We also emphasise the need to improve our understanding of terrestrial ecological processes that influence land-atmosphere interactions at relatively long timescales (decadal-century) as well as at shorter intervals (e.g. hourly).

  1. 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.

  2. The NASA-Lewis terrestrial photovoltaics program

    NASA Technical Reports Server (NTRS)

    Bernatowicz, D. T.

    1974-01-01

    Those parts of the present NASA-Lewis research and technology effort on solar cells and arrays having relevance to terrestrial uses are outlined. These include raising cell efficiency, developing the FEP-covered module concept, and exploring low-cost cell concepts. Solar cell-battery power systems for remote weather stations have been built to demonstrate the capabilities of solar cells for terrestrial applications.

  3. Terrestrial analogs for space exploration habitation systems

    NASA Technical Reports Server (NTRS)

    Campbell, Paul D.; Brown, Jeri W.

    1992-01-01

    The Space Exploration Initiative (SEI) can use early earth-based analogs to simulate many aspects of space flight missions and system operation. These analogs can thus provide information supporting future missions to the moon and to Mars. A study was performed to investigate the potential of terrestrial analogs in simulating human space exploration missions. The study resulted in preliminary requirements and concepts for analog habitation systems, and further study in this area is necessary for SEI terrestrial analog development.

  4. Solar-Terrestrial Relations and Geomagnetic Variations

    NASA Astrophysics Data System (ADS)

    Ogunade, S. O.

    1995-01-01

    An overview of the solar environment and terrestrial magnetism is presented. The interactions of the solar environment and terrestrial magnetism are then discussed as they result in the creation of the magnetosphere and ionosphere with their corresponding current systems. Geomagnetic variations resulting from these current systems are discussed with regards to the observations made on the Earth's surface. Some useful and disruptive effects of the geomagnetic variations on navigation, shortwave radio communication, space satellite orbits and other technological systems are discussed.

  5. 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.

  6. Utilization of the terrestrial cyanobacterial sheet

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

    The terrestrial nitrogen-fixing cyanobacterium, Nostoc commune, is living ranging from polar to desert. N. commune makes visible colonies composed extracellular polymeric substances. N. commune has expected to utilize for agriculture, food and terraforming cause of its extracellular polysaccharide, desiccation tolerance and nitrogen fixation. To exhibit the potential abilities, the N. commune sheet is made to use convenient and evaluated by plant growth and radioactive accumulation. We will discuss utilization of terrestrial cyanobacteria under closed environment.

  7. FORMATION OF TERRESTRIAL PLANETS FROM PROTOPLANETS UNDER A REALISTIC ACCRETION CONDITION

    SciTech Connect

    Kokubo, Eiichiro; Genda, Hidenori E-mail: genda@geo.titech.ac.jp

    2010-05-01

    The final stage of terrestrial planet formation is known as the giant impact stage where protoplanets collide with one another to form planets. So far this stage has been mainly investigated by N-body simulations with an assumption of perfect accretion in which all collisions lead to accretion. However, this assumption breaks for collisions with high velocity and/or a large impact parameter. We derive an accretion condition for protoplanet collisions in terms of impact velocity and angle and masses of colliding bodies, from the results of numerical collision experiments. For the first time, we adopt this realistic accretion condition in N-body simulations of terrestrial planet formation from protoplanets. We compare the results with those with perfect accretion and show how the accretion condition affects terrestrial planet formation. We find that in the realistic accretion model about half of collisions do not lead to accretion. However, the final number, mass, orbital elements, and even growth timescale of planets are barely affected by the accretion condition. For the standard protoplanetary disk model, typically two Earth-sized planets form in the terrestrial planet region over about 10{sup 8} yr in both realistic and perfect accretion models. We also find that for the realistic accretion model, the spin angular velocity is about 30% smaller than that for the perfect accretion model, which is as large as the critical spin angular velocity for rotational instability. The spin angular velocity and obliquity obey Gaussian and isotropic distributions, respectively, independently of the accretion condition.

  8. Anthropogenic transformation of the terrestrial biosphere.

    PubMed

    Ellis, Erle C

    2011-03-13

    Human populations and their use of land have transformed most of the terrestrial biosphere into anthropogenic biomes (anthromes), causing a variety of novel ecological patterns and processes to emerge. To assess whether human populations and their use of land have directly altered the terrestrial biosphere sufficiently to indicate that the Earth system has entered a new geological epoch, spatially explicit global estimates of human populations and their use of land were analysed across the Holocene for their potential to induce irreversible novel transformation of the terrestrial biosphere. Human alteration of the terrestrial biosphere has been significant for more than 8000 years. However, only in the past century has the majority of the terrestrial biosphere been transformed into intensively used anthromes with predominantly novel anthropogenic ecological processes. At present, even were human populations to decline substantially or use of land become far more efficient, the current global extent, duration, type and intensity of human transformation of ecosystems have already irreversibly altered the terrestrial biosphere at levels sufficient to leave an unambiguous geological record differing substantially from that of the Holocene or any prior epoch. It remains to be seen whether the anthropogenic biosphere will be sustained and continue to evolve.

  9. 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.

  10. Evidence for a Mass Dependent Step-Change in the Scaling of Efficiency in Terrestrial Locomotion

    PubMed Central

    Nudds, Robert L.; Codd, Jonathan R.; Sellers, William I.

    2009-01-01

    A reanalysis of existing data suggests that the established tenet of increasing efficiency of transport with body size in terrestrial locomotion requires re-evaluation. Here, the statistical model that described the data best indicated a dichotomy between the data for small (<1 kg) and large animals (>1 kg). Within and between these two size groups there was no detectable difference in the scaling exponents (slopes) relating metabolic (Emet) and mechanical costs (Emech, CM) of locomotion to body mass (Mb). Therefore, no scaling of efficiency (Emech, CM/Emet) with Mb was evident within each size group. Small animals, however, appeared to be generally less efficient than larger animals (7% and 26% respectively). Consequently, it is possible that the relationship between efficiency and Mb is not continuous, but, rather, involves a step-change. This step-change in the efficiency of locomotion mirrors previous findings suggesting a postural cause for an apparent size dichotomy in the relationship between Emet and Mb. Currently data for Emech, CM is lacking, but the relationship between efficiency in terrestrial locomotion and Mb is likely to be determined by posture and kinematics rather than body size alone. Hence, scaling of efficiency is likely to be more complex than a simple linear relationship across body sizes. A homogenous study of the mechanical cost of terrestrial locomotion across a broad range of species, body sizes, and importantly locomotor postures is a priority for future research. PMID:19738898

  11. Analysis of reference gene stability after Israeli acute paralysis virus infection in bumblebees Bombus terrestris.

    PubMed

    Niu, Jinzhi; Cappelle, Kaat; de Miranda, Joachim R; Smagghe, Guy; Meeus, Ivan

    2014-01-01

    To date, there are no validated internal reference genes for the normalization of RT-qPCR data from virus infection experiments with pollinating insects. In this study we evaluated the stability of five candidate internal reference genes: elongation factor-1-alpha (ELF1α), peptidylprolyl isomerase A (PPIA), 60S ribosomal protein L23 (RPL23), TATA-binding protein (TBP) and polyubiquitin (UBI), in relation to Israeli acute paralysis virus (IAPV) infection of Bombus terrestris. We investigated the stability of these genes: in whole bodies and individual body parts, as well as in whole bodies collected at different time intervals after infection with IAPV. Our data identified PPIA as the single, most-optimal internal reference gene and the combination of PPAI-RPL23-UBI as a fully-sufficient multiple internal reference genes set for IAPV infection experiments in B. terrestris.

  12. 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.

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

    PubMed Central

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

    2015-01-01

    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

  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. 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

  16. DISSIPATION AND EXTRA LIGHT IN GALACTIC NUCLEI. II. 'CUSP' ELLIPTICALS

    SciTech Connect

    Hopkins, Philip F.; Cox, Thomas J.; Dutta, Suvendra N.; Hernquist, Lars; Kormendy, John; Lauer, Tod R.

    2009-03-15

    We study the origin and properties of 'extra' or 'excess' central light in the surface brightness profiles of cusp or power-law elliptical galaxies. Dissipational mergers give rise to two-component profiles: an outer profile established by violent relaxation acting on stars already present in the progenitor galaxies prior to the final stages of the merger, and an inner stellar population comprising the extra light, formed in a compact central starburst. By combining a large set of hydrodynamical simulations with data that span a broad range of profiles at various masses, we show that observed cusp ellipticals appear consistent with the predicted 'extra light' structure, and we use our simulations to motivate a two-component description of the observations that allows us to examine how the properties and mass of this component scale with, e.g., the mass, gas content, and other properties of the galaxies. We show how to robustly separate the physically meaningful extra light and outer, violently relaxed profile, and demonstrate that the observed cusps and 'extra light' are reliable tracers of the degree of dissipation in the spheroid-forming merger. We show that the typical degree of dissipation is a strong function of stellar mass, roughly tracing the observed gas fractions of disks of the same mass over the redshift range z {approx} 0-2. We demonstrate a correlation between the strength of this component and effective radius at fixed mass, in the sense that systems with more dissipation are more compact, sufficient to explain the discrepancy in the maximum phase-space and mass densities of ellipticals and their progenitor spirals. We show that the outer shape of the light profile in simulated and observed systems (when fit to properly account for the central light) does not depend on mass, with a mean outer Sersic index {approx}2.5. We also explore how this relates to, e.g., the shapes, kinematic properties, and stellar population gradients of ellipticals. Extra

  17. Body Piercing

    PubMed Central

    Koenig, Laura M; Carnes, Molly

    1999-01-01

    OBJECTIVE To review the current information on medical complications, psychological implications, and legislative issues related to body piercing, a largely unregulated industry in the United States. METHODS We conducted a MEDLINE search of English language articles from 1966 until May 1998 using the search terms “body piercing” and “ear piercing.” Bibliographies of these references were reviewed for additional citations. We also conducted an Internet search for “body piercing” on the World Wide Web. MAIN RESULTS: In this manuscript, we review the available body piercing literature. We conclude that body piercing is an increasingly common practice in the United States, that this practice carries substantial risk of morbidity, and that most body piercing in the United States is being performed by unlicensed, unregulated individuals. Primary care physicians are seeing growing numbers of patients with body pierces. Practitioners must be able to recognize, treat, and counsel patients on body piercing complications and be alert to associated psychological conditions in patients who undergo body piercing. PMID:10354260

  18. 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

    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.

  19. 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

  20. Tip of nose tuberculosis: A rare presentation of extra pulmonary tuberculosis

    PubMed Central

    Bajaj, Darshan K.; Verma, Ajay K.; Jaiswal, Riddhi; Kant, Surya; Patel, Anand; Asnani, Mona

    2016-01-01

    Summary Tuberculosis is notorious that it affects various sites of the human body and presents in different ways. One of the uncommon or rather rare presentation of extra pulmonary tuberculosis is nasal tuberculosis. The nose apart from its physiological functions also contributes to facial aesthetics and gives a defined appearance and its deformity imparts cosmetic disfigurement and unsightly appearance. Both primary and secondary forms of nasal tuberculosis are rare but should be considered in the differential diagnosis of ulcerative or crusting lesions of the nose. Here we report such a case of nasal tuberculosis, which presented as an ulcerative and crusting lesion over the tip of the nose in a female child. The patient was given antituberculous chemotherapy after establishing the diagnosis and responded well to treatment. PMID:27195200

  1. 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.

  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. [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.

  4. 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.

  5. 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

  6. 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.

  7. Extra Dimensions in Photon or Jet plus Missing Transverse Energy

    SciTech Connect

    Cardaci, Marco

    2010-02-10

    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{sup -1} or less. Projected 95% CL exclusion limits as function of luminosity are presented as well.

  8. Detecting the polarization signatures of extra-solar planets

    NASA Astrophysics Data System (ADS)

    Hough, J. H.; Lucas, P. W.; Bailey, J. A.; Tamura, M.; Hirst, E.

    2006-06-01

    Direct detection of the light scattered from extra-solar planets is important in establishing the planet's mass, radius, albedo and nature of the particles in the planetary atmosphere. We describe, and present results from, a new optical polarimeter (PlanetPol) designed to reach fractional polarizations of 10 -6 or better from ground-based telescopes, necessary to detect the polarization signature of unresolved hot-Jupiters.

  9. 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…

  10. 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.

  11. 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

  12. 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

  13. 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

  14. Regional epinephrine kinetics in human heart failure: evidence for extra-adrenal, nonneural release.

    PubMed

    Kaye, D M; Lefkovits, J; Cox, H; Lambert, G; Jennings, G; Turner, A; Esler, M D

    1995-07-01

    A number of neurohumoral processes are activated in heart failure, including an increase in the plasma concentration of epinephrine. Radiotracer methods were applied in 42 patients with severe heart failure and 31 healthy volunteers to ascertain the rate at which epinephrine is released to plasma and to evaluate the contribution of extra-adrenal sources. The increase in arterial plasma epinephrine observed in the heart failure patients was explained principally by a 34% (P < 0.001) reduction in the whole body clearance rate of epinephrine from plasma. Regional venous sampling from the heart, lungs, and hepatomesenteric beds was performed in a subgroup of the study population, revealing a significant increase in the release rate of epinephrine to plasma from these organs in heart failure which accounted for 26% of the whole body plasma epinephrine appearance rate. To establish whether the cardiac epinephrine release was of neuronal origin, a physical (cycling) or mental (difficult mental arithmetic) stressor was applied as a sympathoexcitatory stimulus, given that a proportional release of norepinephrine and epinephrine could be expected if sympathetic nerves were the source. These interventions caused significant increases in the regional spillover of norepinephrine to plasma but not that of epinephrine. These findings suggest that nonadrenal tissues contribute significantly to the whole body epinephrine release rate in heart failure and that this may arise from a site other than sympathetic neurons. PMID:7631847

  15. 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 Endocrine System Eyes Female Reproductive System ...

  16. 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, Kęstutis

    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

  17. Extra-gonadal sites of estrogen biosynthesis and function.

    PubMed

    Barakat, Radwa; Oakley, Oliver; Kim, Heehyen; Jin, Jooyoung; Ko, CheMyong Jay

    2016-09-01

    Estrogens are the key hormones regulating the development and function of reproductive organs in all vertebrates. Recent evidence indicates that estrogens play important roles in the immune system, cancer development, and other critical biological processes related to human well-being. Obviously, the gonads (ovary and testis) are the primary sites of estrogen synthesis, but estrogens synthesized in extra- gonadal sites play an equally important role in controlling biological activities. Understanding non-gonadal sites of estrogen synthesis and function is crucial and will lead to therapeutic interventions targeting estrogen signaling in disease prevention and treatment. Developing a rationale targeting strategy remains challenging because knowledge of extra-gonadal biosynthesis of estrogens, and the mechanism by which estrogen activity is exerted, is very limited. In this review, we will summarize recent discoveries of extra-gonadal sites of estrogen biosynthesis and their local functions and discuss the significance of the most recent novel discovery of intestinal estrogen biosynthesis. [BMB Reports 2016; 49(9): 488-496]. PMID:27530684

  18. Preoperative Embolization of Extra-axial Hypervascular Tumors with Onyx

    PubMed Central

    Fusco, Matthew R.; Salem, Mohamed M.; Reddy, Arra S.; Ogilvy, Christopher S.; Kasper, Ekkehard M.; Thomas, Ajith J.

    2016-01-01

    Objective Preoperative endovascular embolization of intracranial tumors is performed to mitigate anticipated intraoperative blood loss. Although the usage of a wide array of embolic agents, particularly polyvinyl alcohol (PVA), has been described for a variety of tumors, literature detailing the efficacy, safety and complication rates for the usage of Onyx is relatively sparse. Materials and Methods We reviewed our single institutional experience with pre-surgical Onyx embolization of extra-axial tumors to evaluate its efficacy and safety and highlight nuances of individualized cases. Results Five patients underwent pre-surgical Onyx embolization of large or giant extra-axial tumors within 24 hours of surgical resection. Four patients harbored falcine or convexity meningiomas (grade I in 2 patients, grade II in 1 patient and grade III in one patient), and one patient had a grade II hemangiopericytoma. Embolization proceeded uneventfully in all cases and there were no complications. Conclusion This series augments the expanding literature confirming the safety and efficacy of Onyx in the preoperative embolization of extra-axial tumors, underscoring its advantage of being able to attain extensive devascularization via only one supplying pedicle. PMID:27114961

  19. 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.

  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 chemotherapy—with a median survival of 9–12 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. Survival of scalar zero modes in warped extra dimensions

    SciTech Connect

    George, Damien P.

    2011-05-15

    Models with an extra dimension generally contain background scalar fields in a nontrivial configuration, whose stability must be ensured. With gravity present, the extra dimension is warped by the scalars, and the spin-0 degrees of freedom in the metric mix with the scalar perturbations. Where possible, we formally solve the coupled Schroedinger equations for the zero modes of these spin-0 perturbations. When specializing to the case of two scalars with a potential generated by a superpotential, we are able to fully solve the system. We show how these zero modes can be used to construct a solution matrix, whose eigenvalues tell whether a normalizable zero mode exists, and how many negative mass modes exist. These facts are crucial in determining stability of the corresponding background configuration. We provide examples of the general analysis for domain-wall models of an infinite extra dimension and domain-wall soft-wall models. For five-dimensional models with two scalars constructed using a superpotential, we show that a normalizable zero mode survives, even in the presence of warped gravity. Such models, which are widely used in the literature, are therefore phenomenologically unacceptable.

  2. 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.

  3. Helical cosmological magnetic fields from extra-dimensions

    NASA Astrophysics Data System (ADS)

    Atmjeet, Kumar; Seshadri, T. R.; Subramanian, Kandaswamy

    2015-05-01

    We study the inflationary generation of helical cosmological magnetic fields in a higher-dimensional generalization of the electromagnetic theory. For this purpose, we also include a parity breaking piece to the electromagnetic action. The evolution of an extra-dimensional scale factor allows the breaking of conformal invariance of the effective electromagnetic action in 1 +3 dimensions required for such generation. Analytical solutions for the vector potential can be obtained in terms of Coulomb wave-functions for some special cases. We also present numerical solutions for the vector potential evolution in more general cases. In the presence of a higher-dimensional cosmological constant there exist solutions for the scale factors in which both normal and extra dimensional space either inflate or deflate simultaneously with the same rate. In such a scenario, with the number of extra dimensions D =4 , a scale invariant spectrum of helical magnetic field is obtained. The net helicity arises, as one helical mode comes to dominate over the other at the superhorizon scales. A magnetic field strength of the order of 10-9 G can be obtained for the inflationary scale H ≃1 0-3 Mpl . Weaker fields will be generated for lower scales of inflation. Magnetic fields generated in this model respects the bounds on magnetic fields by Planck and γ -ray observations (i.e., 10-16 G

  4. 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...

  5. 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...

  6. 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

  7. 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.

  8. Lunar and terrestrial planet formation in the Grand Tack scenario

    NASA Astrophysics Data System (ADS)

    Jacobson, S. A.; Morbidelli, A.

    2014-09-01

    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 timescale 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 ˜60 and ˜130 My after the formation of the first solids, and was caused most likely by an object with a mass similar to that of Mars.

  9. 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

  10. Core Shadow Zones of Terrestrial Planets and Icy Moons

    NASA Astrophysics Data System (ADS)

    Sohl, F.; Knapmeyer, M.; Gassner, L.; Lange, C.; Wagner, F. W.

    2011-12-01

    The internal dynamics of a planetary core is strongly dependent on its total radius. The volume/surface ratio of a planetary core is linked directly to the outgoing heat flux, which is also an indicator for the element partition between the surrounding mantle and the core. The determination of the core radius is thus an elementary step to better understand the origin and evolution of a planetary body. An observable that has been shown to serve as indicator for core size is the extent of the seismological (P-wave-) core shadow. It appears that the variation of seismic velocities with depth is dominated by quadratic terms, if not an essentially depth independent velocity can be assumed. The observed and predicted core shadow extents of many terrestrial planet models, computed as function of the relative core radius, thus align closely to the analytically derived function for objects with constant velocity profiles. The heavier solar system terrestrial planets, especially Venus and Earth, show the largest deviation from the relation between core radius and shadow width that holds for small bodies. For terrestrial planets more massive than Earth, as found for several exoplanets, the increasing internal pressure would cause increased curvature of tentative seismic rays and thus a more pronounced excursion from the relation for bodies with depth-independent elastic parameters. For Titan, a geophysical network has been suggested as a follow up to the highly successful Cassini-Huygens mission that is currently orbiting Saturn. Titan belongs to the class of weakly differentiated icy moons, which consist of an icy crust, underlain by a deep internal ocean and a central ice-rock body. Unlike any other moon in the solar system, Titan has a thick atmosphere that gives rise to surface processes resembling those on Earth. The goal of the proposed network is an improved understanding of the interactions between atmosphere, surficial ice and a putative subsurface water ocean. Key

  11. 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

  12. 7 CFR 51.881 - U.S. Extra Fancy Export.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. Extra Fancy Export. 51.881 Section 51.881... Vinifera Type) 1 Grades § 51.881 U.S. Extra Fancy Export. “U.S. Extra Fancy Export” consists of grapes which meet the requirements for U.S. Extra Fancy Table and, in addition, meet the packaging...

  13. 7 CFR 51.881 - U.S. Extra Fancy Export.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. Extra Fancy Export. 51.881 Section 51.881... U.S. Extra Fancy Export. “U.S. Extra Fancy Export” consists of grapes which meet the requirements for U.S. Extra Fancy Table and, in addition, meet the packaging requirements set forth in § 51.911....

  14. 7 CFR 51.881 - U.S. Extra Fancy Export.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. Extra Fancy Export. 51.881 Section 51.881... U.S. Extra Fancy Export. “U.S. Extra Fancy Export” consists of grapes which meet the requirements for U.S. Extra Fancy Table and, in addition, meet the packaging requirements set forth in § 51.911....

  15. 7 CFR 51.881 - U.S. Extra Fancy Export.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. Extra Fancy Export. 51.881 Section 51.881... Vinifera Type) 1 Grades § 51.881 U.S. Extra Fancy Export. “U.S. Extra Fancy Export” consists of grapes which meet the requirements for U.S. Extra Fancy Table and, in addition, meet the packaging...

  16. Predictability of the terrestrial carbon cycle.

    PubMed

    Luo, Yiqi; Keenan, Trevor F; Smith, Matthew

    2015-05-01

    Terrestrial ecosystems sequester roughly 30% of anthropogenic carbon emission. However this estimate has not been directly deduced from studies of terrestrial ecosystems themselves, but inferred from atmospheric and oceanic data. This raises a question: to what extent is the terrestrial carbon cycle intrinsically predictable? In this paper, we investigated fundamental properties of the terrestrial carbon cycle, examined its intrinsic predictability, and proposed a suite of future research directions to improve empirical understanding and model predictive ability. Specifically, we isolated endogenous internal processes of the terrestrial carbon cycle from exogenous forcing variables. The internal processes share five fundamental properties (i.e., compartmentalization, carbon input through photosynthesis, partitioning among pools, donor pool-dominant transfers, and the first-order decay) among all types of ecosystems on the Earth. The five properties together result in an emergent constraint on predictability of various carbon cycle components in response to five classes of exogenous forcing. Future observational and experimental research should be focused on those less predictive components while modeling research needs to improve model predictive ability for those highly predictive components. We argue that an understanding of predictability should provide guidance on future observational, experimental and modeling research.

  17. 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.

  18. 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.

  19. 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...

  20. 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...

  1. 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...

  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, 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...

  4. 7 CFR 51.2750 - U.S. Extra Large Virginia.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. Extra Large Virginia. 51.2750 Section 51.2750... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Shelled Virginia Type Peanuts Grades § 51.2750 U.S. Extra Large Virginia. “U.S. Extra Large Virginia” consists of shelled Virginia...

  5. 7 CFR 51.2750 - U.S. Extra Large Virginia.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. Extra Large Virginia. 51.2750 Section 51.2750... STANDARDS) United States Standards for Shelled Virginia Type Peanuts Grades § 51.2750 U.S. Extra Large Virginia. “U.S. Extra Large Virginia” consists of shelled Virginia type peanut kernels of similar...

  6. 7 CFR 51.2750 - U.S. Extra Large Virginia.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. Extra Large Virginia. 51.2750 Section 51.2750... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Shelled Virginia Type Peanuts Grades § 51.2750 U.S. Extra Large Virginia. “U.S. Extra Large Virginia” consists of shelled Virginia...

  7. 7 CFR 51.880 - U.S. Extra Fancy Table.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. Extra Fancy Table. 51.880 Section 51.880 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... U.S. Extra Fancy Table. “U.S. Extra Fancy Table” consists of bunches of well developed grapes of...

  8. 7 CFR 51.880 - U.S. Extra Fancy Table.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. Extra Fancy Table. 51.880 Section 51.880 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Vinifera Type) 1 Grades § 51.880 U.S. Extra Fancy Table. “U.S. Extra Fancy Table” consists of bunches...

  9. 7 CFR 51.880 - U.S. Extra Fancy Table.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. Extra Fancy Table. 51.880 Section 51.880 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... U.S. Extra Fancy Table. “U.S. Extra Fancy Table” consists of bunches of well developed grapes of...

  10. Influence of Tribulus terrestris on testicular enzyme in fresh water ornamental fish Poecilia latipinna.

    PubMed

    Kavitha, P; Subramanian, P

    2011-12-01

    The influence of Tribulus terrestris on the activities of testicular enzyme in Poecilia latipinna was assessed in lieu of reproductive manipulation. Different concentrations of (100, 150, 200, 250, and 300 mg) Tribulus terrestris extract and of a control were tested for testicular activity of enzymes in Poecilia latipinna for 2 months. The testis and liver were homogenized separately in 0.1 mol/l potassium phosphate buffer (0.1 mol/l, pH 7.2). The crude homogenate was centrifuged, and supernatant obtained was used as an enzyme extract for determination of activities. The activities of testicular functional enzyme ALP, ACP, SDH, LDH, and G6PDH levels were changed to different extent in treated groups compared with that of the control. The total body weight and testis weight were increased with the Tribulus terrestris-treated fish (Poecilia latipinna). These results suggest that Tribulus terrestris induced the testicular enzyme activity that may aid in the male reproductive functions. It is discernible from the present study that Tribulus terrestris has the inducing effect on reproductive system of Poecilia latipinna.

  11. DNA barcoding reveals cryptic diversity in Lumbricus terrestris L., 1758 (Clitellata): resurrection of L. herculeus (Savigny, 1826).

    PubMed

    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

  12. Solar Variability and Climate Impact on Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Bertaux, J.-L.

    2006-08-01

    Some possible factors of climate changes and of long term climate evolution are discussed with regard of the three terrestrial planets, Earth, Venus and Mars. Two positive feedback mechanisms involving liquid water, i.e., the albedo mechanism and the greenhouse effect of water vapour, are described. These feedback mechanisms respond to small external forcings, such as resulting from solar or astronomical constants variability, which might thus result in large influences on climatic changes on Earth. On Venus, reactions of the atmosphere with surface minerals play an important role in the climate system, but the involved time scales are much larger. On Mars, climate is changing through variations of the polar axis inclination over time scales of ˜105 106 years. Growing evidence also exists that a major climatic change happened on Mars some 3.5 to 3.8 Gigayears ago, leading to the disappearance of liquid water on the planet surface by eliminating most of the CO2 atmosphere greenhouse power. This change might be due to a large surge of the solar wind, or to atmospheric erosion by large bodies impacts. Indeed, except for their thermospheric temperature response, there is currently little evidence for an effect of long-term solar variability on the climate of Venus and Mars. This fact is possibly due to the absence of liquid water on these terrestrial planets.

  13. Bold coloration and the evolution of aposematism in terrestrial carnivores.

    PubMed

    Stankowich, Theodore; Caro, Tim; Cox, Matthew

    2011-11-01

    Several species of terrestrial carnivores (Mammalia: Carnivora) have bold contrasting color patterns that, in some species, apparently signal possession of noxious anal gland secretions, or even physical strength and great ferocity; yet the evolutionary drivers of both placement and patterning of these contrasting pelage colors on the body, and the ecological selection pressures underlying them, have yet to be systematically examined. Here we explore these issues and find not only that both boldly colored and dichromatic species do indeed often use anal gland secretions for defense, but also that such species are stockier, and live in more exposed habitats where other forms of antipredator defense are limited. We also show that white dorsa are found in sprayers that are primarily nocturnal; that horizontal stripes are found in species that have an ability to spray anal secretions accurately; and that facial stripes are found in burrowing species that typically leave only their heads exposed to attack. Our phylogenetic reconstructions suggest that aposematic coloration has evolved more than once in terrestrial carnivores. We finish by outlining five evolutionary routes for patterns of pelage coloration in this taxon.

  14. 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.

  15. 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

  16. 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.

  17. Terrestrial impact - The record in the rocks

    NASA Astrophysics Data System (ADS)

    Grieve, Richard A.

    1991-09-01

    The terrestrial impact craters are mostly recognized not by their morphology but by the occurrence of the characteristic shock metamorphic effects. The recognition of the diagnostic shock metamorphic effects and the signature of the projectile contamination through geochemical anomalies in impact lithologies provide the basis for recognizing the impact signature in K/T boundary samples and for testing hypothesis of periodic cometary showers. It is emphasized, however, that, in evaluating and making interpretations based on the overall cratering record, it is important to realize that one of the basic characteristics of the terrestrial impact record is its bias to geologically young craters on the better known cratonic areas and the fact that the sample of the currently known (about 130) terrestrial craters is deficient in small (D less than 20 km) craters.

  18. Evaluation of five different suture materials in the skin of the earthworm (Lumbricus terrestris).

    PubMed

    Salgado, Melissa A; Lewbart, Gregory A; Christian, Larry S; Griffith, Emily H; Law, Jerry McHugh

    2014-01-01

    The purpose of this study was to determine which suture material is the most appropriate for dermal closure of terrestrial annelids. This paper describes the tissue reactions of the earthworm, Lumbricus terrestris, to five different types of suture materials in order to determine which suture material is the most appropriate for dermal closure. Silk, monofilament nylon, polydiaxonone, polyglactin 910, and chromic gut were studied. There was mild to moderate tissue reaction to all five suture materials. In all of the biopsies wound-healing reaction consisted of aggregates of blastemal cells which appeared in various stages of dedifferentiation from the body wall. Inflammatory cells infiltrated the wound sites, reminiscent of the typical foreign body reaction in vertebrates. The results indicate polyglactin 910 would be the best suture material with regards to tissue security and reaction scores. Chromic gut occupies the next position but there were problems with suture security over time. This appears to be the first suture material performance study on a terrestrial invertebrate. The earthworm, Lumbricus terrestris, was chosen for its wide availability, size, and the extensive species knowledge base. The earthworm may prove to be a good surgical/suture model for economically important invertebrates such as mollusks, tunicates, and insect larval stages. PMID:25143875

  19. Body lice

    MedlinePlus

    ... off the body. Your provider may prescribe a skin cream or a wash that contains permethrin, malathione, or benzyl alcohol. If your case is severe, the provider may prescribe medicine that you take by mouth.

  20. Body Image

    MedlinePlus

    ... spider veins Body dysmorphic disorder (BDD) Eating disorders Anorexia nervosa Binge eating disorder Bulimia nervosa Over-exercising ... conditions? Visit our Mental health section. Fact sheets Anorexia nervosa Binge eating disorder Bulimia nervosa Cosmetics and ...

  1. Some effects of pollutants in terrestrial ecosystems

    USGS Publications Warehouse

    Stickel, W.H.; McIntyre, A.D.; Mills, C.F.

    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

  2. Terrestrial impact melt rocks and glasses

    NASA Astrophysics Data System (ADS)

    Dressler, B. O.; Reimold, W. U.

    2001-12-01

    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

  3. Terrestrial impact melt rocks and glasses

    NASA Astrophysics Data System (ADS)

    Dressler, B. O.; Reimold, W. U.

    2001-12-01

    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

  4. The evolution of acoustic size exaggeration in terrestrial mammals.

    PubMed

    Charlton, Benjamin D; Reby, David

    2016-01-01

    Recent studies have revealed that some mammals possess adaptations that enable them to produce vocal signals with much lower fundamental frequency (F0) and formant frequency spacing (ΔF) than expected for their size. Although these adaptations are assumed to reflect selection pressures for males to lower frequency components and exaggerate body size in reproductive contexts, this hypothesis has not been tested across a broad range of species. Here we show that male terrestrial mammals produce vocal signals with lower ΔF (but not F0) than expected for their size in mating systems with greater sexual size dimorphism. We also reveal that males produce calls with higher than expected F0 and ΔF in species with increased sperm competition. This investigation confirms that sexual selection favours the use of ΔF as an acoustic size exaggerator and supports the notion of an evolutionary trade-off between pre-copulatory signalling displays and sperm production. PMID:27598835

  5. Lunar and terrestrial crusts - A contrast in origin and evolution

    NASA Astrophysics Data System (ADS)

    Taylor, S. R.

    1982-09-01

    Planetary crusts, differing in composition from that of the bulk planet, and containing large concentrations of incompatible elements such as K, U and Th, may arise in two distinctly different ways. The first, exemplified by the moon, involves flotation of a feldspathic crust during an initial melting episode in which much of the planetary body was molten. The second, probably more common type of crust is formed as a consequence of partial melting, in response to radioactive heating, in the planetary interior and the eruption of basaltic lavas. Examples include the lunar maria and the oceanic crust of the earth. Subsequent partial melting epsiodes, involving recycling into the mantle, or lower crustal melting epsiodes produce more acidic crusts, of which the terrestrial continental crust forms the type example. The upper crust requires at least three successive partial melting events.

  6. The evolution of acoustic size exaggeration in terrestrial mammals

    PubMed Central

    Charlton, Benjamin D.; Reby, David

    2016-01-01

    Recent studies have revealed that some mammals possess adaptations that enable them to produce vocal signals with much lower fundamental frequency (F0) and formant frequency spacing (ΔF) than expected for their size. Although these adaptations are assumed to reflect selection pressures for males to lower frequency components and exaggerate body size in reproductive contexts, this hypothesis has not been tested across a broad range of species. Here we show that male terrestrial mammals produce vocal signals with lower ΔF (but not F0) than expected for their size in mating systems with greater sexual size dimorphism. We also reveal that males produce calls with higher than expected F0 and ΔF in species with increased sperm competition. This investigation confirms that sexual selection favours the use of ΔF as an acoustic size exaggerator and supports the notion of an evolutionary trade-off between pre-copulatory signalling displays and sperm production. PMID:27598835

  7. 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

  8. Were early pterosaurs inept terrestrial locomotors?

    PubMed

    Witton, Mark P

    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

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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}.

  15. 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.

  16. Comparison of high resolution terrestrial laser scanning and terrestrial photogrammetry for modeling applications

    NASA Astrophysics Data System (ADS)

    Özdemir, Samed; Bayrak, Temel

    2016-04-01

    3D documentation of cultural heritage and engineering projects is an important matter. These documentation applications, requires highest possible accuracy and detail to represent the actual surface correctly. Terrestrial photogrammetric method which is employed to produce 3D models to day, now can obtain dense point clouds thanks to advancements in computer technology. Terrestrial laser scanners gained popularity in the last decade because of their high capacity and today they are being widely used in many applications. However every application has its own requirements that depend on the type of application, modeling environment, accuracy and budget limitations. This means, for every application highest accuracy instruments are not always best, considering the facts that mentioned before. In this study, laser scanner and terrestrial photogrammetric methods' spatial and model accuracies investigated under various conditions which include measuring targets at different instrument to object distances then investigating the accuracy of these measurements, modeling an irregular shaped surface to compare two surfaces volume and surface areas, at last comparing dimensions of known geometrical shaped small objects. Also terrestrial laser scanners and terrestrial photogrammetric methods most suitable application conditions investigated in terms of cost, time, mobility and accuracy. Terrestrial laser scanner has the ability to, measure distances under cm accuracy and directly measuring 3D world but there is also some drawbacks like sensitive, bulky and expensive equipment. When it comes to terrestrial photogrammetry, it has above cm accuracy, comparatively fast (considering the image acquisition stage), inexpensive but it can be affected by the coarse geometry, surface texture and the environmental lighting. Key Words: Accuracy, Comparison, Model, Terrestrial Photogrammetry, Terrestrial Laser Scanning,.

  17. Vitamin D and extra-skeletal health: causality or consequence.

    PubMed

    Al Nozha, Omar M

    2016-07-01

    Vitamin D deficiency /insufficiency is widely recognized as a global health problem that is likely to be involved in pathogenesis or progression of many acute and chronic health disorders. Its relation to skeletal health has been clearly demonstrated and thoroughly examined. This review aims to highlight the continuous debate about the relation between vitamin D and extra-skeletal health and whether it is a causality or just an association. Overall, the available evidence does not meet the criteria for establishing cause-and-effect relationships because of the limitations of observational studies to corroborate the causality due to many potential confounders. Moreover, the causal relationship couldn't be established in randomized studies or in many meta-analyses. This may reflect the fact that vitamin D level reduction is just a biomarker of ill health. The inflammatory processes involved in the disease occurrence and the functional limitations of the diseases would have a role in reducing serum 25-hydroxy vitamin D "25 (OH) D" level, which would explain why low vitamin D is reported in a wide range of disorders. This may underscore the possibility of harm instead of benefit of vitamin D supplementation when its exact role is not fully established, thus many guidelines and interest groups are still hesitant toward recommending replacement in extra-skeletal disease. Future directions entails the need for a large well-designed randomized control trials (RCTs) to resolve the active debate on the benefits of vitamin D replacement for extra-skeletal disease, and not only that, future studies should establish specific, clinically relevant effects of vitamin D repletion, provide cut-values for optimal serum levels of 25 (OH) D, and appropriate doses for non-skeletal health benefits.

  18. Vitamin D and extra-skeletal health: causality or consequence

    PubMed Central

    Al Nozha, Omar M.

    2016-01-01

    Vitamin D deficiency /insufficiency is widely recognized as a global health problem that is likely to be involved in pathogenesis or progression of many acute and chronic health disorders. Its relation to skeletal health has been clearly demonstrated and thoroughly examined. This review aims to highlight the continuous debate about the relation between vitamin D and extra-skeletal health and whether it is a causality or just an association. Overall, the available evidence does not meet the criteria for establishing cause-and-effect relationships because of the limitations of observational studies to corroborate the causality due to many potential confounders. Moreover, the causal relationship couldn’t be established in randomized studies or in many meta-analyses. This may reflect the fact that vitamin D level reduction is just a biomarker of ill health. The inflammatory processes involved in the disease occurrence and the functional limitations of the diseases would have a role in reducing serum 25-hydroxy vitamin D “25 (OH) D” level, which would explain why low vitamin D is reported in a wide range of disorders. This may underscore the possibility of harm instead of benefit of vitamin D supplementation when its exact role is not fully established, thus many guidelines and interest groups are still hesitant toward recommending replacement in extra-skeletal disease. Future directions entails the need for a large well-designed randomized control trials (RCTs) to resolve the active debate on the benefits of vitamin D replacement for extra-skeletal disease, and not only that, future studies should establish specific, clinically relevant effects of vitamin D repletion, provide cut-values for optimal serum levels of 25 (OH) D, and appropriate doses for non-skeletal health benefits. PMID:27610068

  19. Vitamin D and extra-skeletal health: causality or consequence.

    PubMed

    Al Nozha, Omar M

    2016-07-01

    Vitamin D deficiency /insufficiency is widely recognized as a global health problem that is likely to be involved in pathogenesis or progression of many acute and chronic health disorders. Its relation to skeletal health has been clearly demonstrated and thoroughly examined. This review aims to highlight the continuous debate about the relation between vitamin D and extra-skeletal health and whether it is a causality or just an association. Overall, the available evidence does not meet the criteria for establishing cause-and-effect relationships because of the limitations of observational studies to corroborate the causality due to many potential confounders. Moreover, the causal relationship couldn't be established in randomized studies or in many meta-analyses. This may reflect the fact that vitamin D level reduction is just a biomarker of ill health. The inflammatory processes involved in the disease occurrence and the functional limitations of the diseases would have a role in reducing serum 25-hydroxy vitamin D "25 (OH) D" level, which would explain why low vitamin D is reported in a wide range of disorders. This may underscore the possibility of harm instead of benefit of vitamin D supplementation when its exact role is not fully established, thus many guidelines and interest groups are still hesitant toward recommending replacement in extra-skeletal disease. Future directions entails the need for a large well-designed randomized control trials (RCTs) to resolve the active debate on the benefits of vitamin D replacement for extra-skeletal disease, and not only that, future studies should establish specific, clinically relevant effects of vitamin D repletion, provide cut-values for optimal serum levels of 25 (OH) D, and appropriate doses for non-skeletal health benefits. PMID:27610068

  20. Sturge-Weber syndrome: oral and extra-oral manifestations.

    PubMed

    Tripathi, Amitandra Kumar; Kumar, Vivek; Dwivedi, Rahul; Saimbi, Charanjit Singh

    2015-01-01

    Sturge-Weber syndrome is a rare, congenital, neuro-oculo-cutaneous disorder which is characterised extra-orally by unilateral port wine stains on the face, glaucoma, seizures and mental retardation, and intra-orally by ipsilateral gingival haemangioma which frequently affects the maxilla or mandible. In the present case, a 15-year-old female patient presented with a port wine stain on the right side of the face and glaucoma of the right eye, and intra-orally with gingival haemangioma on the right side of the maxilla. PMID:25766438

  1. 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.

  2. Extra intestinal manifestations and complications in inflammatory bowel disease.

    PubMed

    Marineaţă, Anca; Rezuş, Elena; Mihai, Cătălina; Prelipcean, Cristina Cijevschi

    2014-01-01

    Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), doesn't affect only the intestinal tract, but also involve other organs such as: eyes, skin, joints, liver and biliary tracts, kidneys, lungs, vascular system. It is difficult to differentiate the true extraintestinal manifestations from secondary extraintestinal complications. The pathogenetic autoimmune mechanisms include genetic susceptibility, antigenic display of autoantigen, aberrant self-recognition and immunopathogenetic autoantibodies against organ-specific cellular antigens shared by colon and extra-colonic organs. An important role is owned by microbes due to molecular mimicry. This paper reviews the frequency, clinical presentation and therapeutic implications of extraintestinal symptoms in inflammatory bowel diseases. PMID:25076688

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. Extra-cardiac stimulators: what do cardiologists need to know?

    PubMed

    Guinand, Alexandre; Noble, Stéphane; Frei, Angela; Renard, Julien; Tramer, Martin R; Burri, Haran

    2016-09-01

    For several decades, treating patients with pacemakers has been the privilege of cardiologists. However, in the last 30 years, researchers have found new targets for electrical stimulation in different clinical subspecialities, such as deep brain stimulation (for the treatment of Parkinson's disease, essential tremor, dystonia, and some psychiatric illnesses); spinal cord stimulation (for refractory angina, chronic pain, and peripheral artery disease); and sacral (for diverse urologic and proctologic conditions), vagal (for epilepsy), and phrenic nerve stimulation (for sleep apnoea). The purpose of this article is to familiarize cardiologists with these 'extra-cardiac pacemakers' and to discuss potential issues that must be addressed when these patients undergo cardiac procedures. PMID:27234870

  8. Medicare extra: a comprehensive benefit option for Medicare beneficiaries.

    PubMed

    Davis, Karen; Moon, Marilyn; Cooper, Barbara; Schoen, Cathy

    2005-01-01

    The proposed Part E, Medicare Extra, outlined in this paper adds a comprehensive benefit option to Medicare, eliminating the need for beneficiaries to purchase a private drug plan and Medigap supplemental coverage. Financed by a budget-neutral beneficiary premium, it has the advantages of greater simplicity, efficiency, and value without adding to federal costs. Beneficiaries now enrolled in Medigap plans would save money, as could employers by choosing a lower-cost alternative to current retiree health plans. Eliminating some of the excess payments to Medicare Advantage plans would yield savings that could be used to help finance premium subsidies for low-income beneficiaries.

  9. 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.

  10. 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 Kaluza–Klein 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 Kaluza–Klein zero mode can mix with the SM higgs and further constraints can be applied.

  11. Scalar dark matter in an extra dimension inspired model

    NASA Astrophysics Data System (ADS)

    Lineros, Roberto; Pereira dos Santos, Fabio

    2016-05-01

    In this work we consider a singlet scalar propagating in a flat large extra dimension. The first Kaluza-Klein mode associated to this singlet scalar will be a viable dark matter candidate. The tower of new particles enriches the calculation of the relic density due effect of coannihilation. For large mass splitting, the model converges to the predictions of the singlet dark matter model. For nearly degenerate mass spectrum, coannihilations increase the cross-sections used for direct and indirect dark matter searches. We investigate the impact of the Kaluza-Klein tower associated to singlet scalar for indirect and direct detection of dark matter.

  12. High efficiency, long life terrestrial solar panel

    NASA Technical Reports Server (NTRS)

    Chao, T.; Khemthong, S.; Ling, R.; Olah, S.

    1977-01-01

    The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evaluation of the cell performance was begun. Based on the power output analysis, the goal of a 13% efficiency module was achievable.

  13. Extraterrestrial amino acids and terrestrial life

    NASA Astrophysics Data System (ADS)

    Chyba, Christopher F.

    1996-07-01

    Since the Swedish chemist Baron Jöns Jacob Berzelius first analysed the Alais meteorite for organic molecules' in 1834, attempts to forge a link between extraterrestrial organic materials and terrestrial life have remained alluring, but often deceptive. New studies reported in this and last week's issues hold the promise of important advances in both endeavours. (AIP)

  14. Nucleosynthesis in the terrestrial and solar atmospheres

    NASA Technical Reports Server (NTRS)

    Yu, C.; Zhou, R.; Zhan, S.

    1985-01-01

    Variations of Delta D, delta C-13, Delta C-14 and Delta O-18 with time were measured by a lot of experiments. Many abnormalities of isotope abundances in cosmic rays were found by balloons and satellites. It is suggested that these abnormalities are related to nuclearsynthesis in the terrestrial and solar atmospheres and are closely related to solar activities.

  15. Does extra corticosterone elicit increased begging and submissiveness in subordinate booby (Sula nebouxii) chicks?

    PubMed

    Vallarino, A; Wingfield, J C; Drummond, H

    2006-07-01

    We tested whether in two-chick broods of the blue-footed booby (Sula nebouxii) elevated circulating corticosterone in the socially subordinate broodmate facilitates submissive behavior and/or enhances food solicitation. Implanting corticosterone in 17 subordinate chicks (experimental broods) produced changes in the behavior of chicks and parents over the first two days, relative to 17 matched families (control broods) where subordinate chicks were implanted with empty capsules. Experimental broods showed increased activity/wakefulness of the dominant broodmate and, consequently, increased simultaneous activity of both broodmates, but there was scant evidence that subordinates submitted more readily when attacked. Implanted subordinates increased their rate of spontaneous submission over the total observation time, but this increase was mostly explained by the additional time when both broodmates were simultaneously active. There was little sign that extra corticosterone induced more begging, except possibly by eliciting increased activity. Experimental broods increased their rate of feeding, and most if not all of the increase was due to the increased activity and increased feeding rate of dominant broodmates. On the third and fourth days after implantation all effects of implanted corticosterone disappeared, except for the elevated activity and feeding rates of dominant chicks. At the end of four days, subordinates implanted with corticosterone showed no increase in circulating corticosterone and experimental broods showed no gain in mass or body size, relative to controls. Extra corticosterone, above the high level that normally circulates in subordinate chicks, apparently does not enhance submission to aggression or food solicitation, but provokes a cascade of changes in the behavior of broodmates and parents.

  16. Does extra corticosterone elicit increased begging and submissiveness in subordinate booby (Sula nebouxii) chicks?

    PubMed

    Vallarino, A; Wingfield, J C; Drummond, H

    2006-07-01

    We tested whether in two-chick broods of the blue-footed booby (Sula nebouxii) elevated circulating corticosterone in the socially subordinate broodmate facilitates submissive behavior and/or enhances food solicitation. Implanting corticosterone in 17 subordinate chicks (experimental broods) produced changes in the behavior of chicks and parents over the first two days, relative to 17 matched families (control broods) where subordinate chicks were implanted with empty capsules. Experimental broods showed increased activity/wakefulness of the dominant broodmate and, consequently, increased simultaneous activity of both broodmates, but there was scant evidence that subordinates submitted more readily when attacked. Implanted subordinates increased their rate of spontaneous submission over the total observation time, but this increase was mostly explained by the additional time when both broodmates were simultaneously active. There was little sign that extra corticosterone induced more begging, except possibly by eliciting increased activity. Experimental broods increased their rate of feeding, and most if not all of the increase was due to the increased activity and increased feeding rate of dominant broodmates. On the third and fourth days after implantation all effects of implanted corticosterone disappeared, except for the elevated activity and feeding rates of dominant chicks. At the end of four days, subordinates implanted with corticosterone showed no increase in circulating corticosterone and experimental broods showed no gain in mass or body size, relative to controls. Extra corticosterone, above the high level that normally circulates in subordinate chicks, apparently does not enhance submission to aggression or food solicitation, but provokes a cascade of changes in the behavior of broodmates and parents. PMID:16530762

  17. Mouse early extra-embryonic lineages activate compensatory endocytosis in response to poor maternal nutrition.

    PubMed

    Sun, Congshan; Velazquez, Miguel A; Marfy-Smith, Stephanie; Sheth, Bhavwanti; Cox, Andy; Johnston, David A; Smyth, Neil; Fleming, Tom P

    2014-03-01

    Mammalian extra-embryonic lineages perform the crucial role of nutrient provision during gestation to support embryonic and fetal growth. These lineages derive from outer trophectoderm (TE) and internal primitive endoderm (PE) in the blastocyst and subsequently give rise to chorio-allantoic and visceral yolk sac placentae, respectively. We have shown maternal low protein diet exclusively during mouse preimplantation development (Emb-LPD) is sufficient to cause a compensatory increase in fetal and perinatal growth that correlates positively with increased adult-onset cardiovascular, metabolic and behavioural disease. Here, to investigate early mechanisms of compensatory nutrient provision, we assessed the influence of maternal Emb-LPD on endocytosis within extra-embryonic lineages using quantitative imaging and expression of markers and proteins involved. Blastocysts collected from Emb-LPD mothers within standard culture medium displayed enhanced TE endocytosis compared with embryos from control mothers with respect to the number and collective volume per cell of vesicles with endocytosed ligand and fluid and lysosomes, plus protein expression of megalin (Lrp2) LDL-family receptor. Endocytosis was also stimulated using similar criteria in the outer PE-like lineage of embryoid bodies formed from embryonic stem cell lines generated from Emb-LPD blastocysts. Using an in vitro model replicating the depleted amino acid (AA) composition found within the Emb-LPD uterine luminal fluid, we show TE endocytosis response is activated through reduced branched-chain AAs (leucine, isoleucine, valine). Moreover, activation appears mediated through RhoA GTPase signalling. Our data indicate early embryos regulate and stabilise endocytosis as a mechanism to compensate for poor maternal nutrient provision.

  18. 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.

  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. In this photograph, a patient undergoes an open MRI.

  20. 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.