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1

ExtraTerrestrial Radio Transmissions  

Microsoft Academic Search

WE are witness again to a surge of interest in, and speculation about, extra-terrestrial radio transmissions which had an earlier flare in the late twenties1. The favourable change in climate for the expression of such ideas since the turn of the century has been of particular interest to me. In 1899, Nikola Tesla established an experimental station at Colorado Springs,

Leland I. Anderson

1961-01-01

2

Messaging to Extra-Terrestrial Intelligence  

E-print Network

Throughout the entire history of terrestrial civilization, only four projects involving transmitting of interstellar radio messages (IRMs) have yet been fully developed and realized. Nevertheless, we should understand a simple thing -- if all civilizations in the Universe are only recipients, and not message-sending civilizations, than no SETI searches make any sense. We present the theory and methodology of composing and transmitting of future IRMs.

Alexander Zaitsev

2006-10-05

3

Search for Extra-terrestrial Intelligence Donna M. Jurdy  

E-print Network

NASA/JPL SETI - Search for Extra-terrestrial Intelligence Donna M. Jurdy Northwestern University #12;#12;H.G. Wells The War of the Worlds (1898) #12;Viking composite of Mars mid 1970's #12 Equation How many civilizations are out there? #12;Page 1 of 1 #12;#12;#12;Arecibo Message Broadcast

Jurdy, Donna M.

4

Black-body radiation in extra dimensions  

E-print Network

The general form of the Stefan-Boltzmann law for the energy density of black-body radiation is generalized to a spacetime with extra dimensions using standard kinetic and thermodynamic arguments. From statistical mechanics one obtains an exact formula. In a field-theoretic derivation, the Maxwell field must be quantized. The notion of electric and magnetic fields is different in spacetimes with more than four dimensions. While the energy-momentum tensor for the Maxwell field is traceless in four dimensions, it is not so when there are extra dimensions. But it is shown that its thermal average is traceless and in agreement with the thermodynamic results.

H. Alnes; F. Ravndal; I. K. Wehus

2005-06-16

5

Migration & Extra-solar Terrestrial Planets: Watering the Planets  

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

6

A Review of Extra-Terrestrial Mining Concepts  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

7

The Terrestrial Planets Large Bodies  

E-print Network

[MESSENGER] Hot Spot Shield Volcanoes on Mars [NASA MGS] Evidence of past volcanism on Mercury and Mars #12, extinct shield volcanoes. #12;Solid inner core Liquid outer core The large terrestrial planets cool more) on the Moon Lava plains and volcanic vents on Mercury Hot-spot volcanoes on Mars Crustal Shaping: Primary

Gaudi, B. Scott

8

Reducing Extra-Terrestrial Excavation Forces with Percussion  

NASA Technical Reports Server (NTRS)

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

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

2012-01-01

9

HYDROTHERMAL VENT COMPLEXES AND THE SEARCH FOR EXTRA-TERRESTRIAL WATER. H. Svensen1  

E-print Network

HYDROTHERMAL VENT COMPLEXES AND THE SEARCH FOR EXTRA-TERRESTRIAL WATER. H. Svensen1 , G. Gisler1-terrestrial implications of a recently discovered type of geological structures: Hydrothermal vent com- plexes (HVC satellite images (Karoo Basin) as ridges and as saucer-shaped features up to 60 km in di- ameter (Fig. 2). 2

Mazzini, Adriano

10

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

NASA Astrophysics Data System (ADS)

The telluric planets and the asteroid belt display the same internal structure with a metallic inner core and a silicate outer shell. Experimental data and petrological evidence in silicate systems show that granite can be produced by extreme igneous differentiation through various types of igneous processes. On Moon, 4.4-3.9 Ga granite clasts display dry mineral assemblages. They correspond to at least 8 discrete intrusive events. Large K/Ca enrichment and low REE abundances in granite relative to KREEP are consistent with silicate liquid immiscibility, a process observed in melt inclusions within olivine of lunar basalts and in lunar meteorites. Steep-sided domes identified by remote sensing can represent intrusive or extrusive felsic formations. On Mars, black-and-white rhythmic layers observed on the Tharsis rise along the flanks of the peripheral scarps of the Tharsis Montes giant volcanoes suggest the possible eruption of felsic pyroclastites. Though no true granites were found so far in the Martian SNC meteorites, felsic glasses and mesostases were identified and a component close to terrestrial continental (granitic) crust is inferred from trace element and isotope systematics. Venus has suffered extensive volcanic resurfacing, whereas folded and faulted areas resemble terrestrial continents. Near large shield volcanoes, with dominant basaltic compositions, steep-sided domes have been interpreted as non-degassed silicic extrusions. The hypothesis of a granitic component is "tantalising". Extra-terrestrial granite is frequently found as clasts and mesostases in asteroidal meteorites. Porphyritic textures, with alkali feldspar crystals up to several centimetres in size, were observed in silicate enclaves within iron meteorites. In the chondrite clan, polymict breccias can contain granitic clasts, whose provenance is debated. One clast from the Adzhi-Bogdo meteorite yields a 4.53 ± 0.03 Ga Pb-Pb age, making it the oldest known granite in the solar system. The 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.

Bonin, Bernard

2012-11-01

11

Techniques for the measurement of extra-terrestrial soft x-radiation  

Microsoft Academic Search

The electromagnetic spectrum has no clearly defined boundaries separating one part from another. Rather has each region become associated with a name which has arisen historically. It is therefore necessary to make some fairly arbitrary decision on the region to be included in the term soft X-radiation. The study of extra-terrestrial X-radiation grew historically from photometer type measurements using metal

R. L. F. Boyd; R. L. F

1965-01-01

12

Power optimization of an extra-terrestrial, solar-radiant stirling heat engine  

Microsoft Academic Search

The power output and thermal efficiency of a finite-time, optimized, extra-terrestrial, solar-radiant Stirling heat engine have been studied. The thermodynamic model adopted is a regenerative gas Stirling cycle coupled to a heat source and heat sink by radiant heat transfer. Both the heat source and sink are assumed to have infinite heat-capacity rates. Expressions are obtained for optimum power and

David A. Blank; Chih Wu

1995-01-01

13

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

NASA Astrophysics Data System (ADS)

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

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

2008-05-01

14

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

PubMed

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

Dominik, Martin; Zarnecki, John C

2011-02-13

15

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

PubMed

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

Leighton, T G

2012-03-01

16

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

NASA Astrophysics Data System (ADS)

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

de Vladar, Harold P.

2013-01-01

17

The New Worlds Observer: a mission for high-resolution spectroscopy of extra-solar terrestrial planets  

NASA Astrophysics Data System (ADS)

The New Worlds Observer (NWO) is a proposed space mission to provide high resolution spectroscopy from the far UV to the near IR of extra-solar terrestrial sized planets. The design of NWO is based on the concept of a large, space-based, pinhole camera made up of two spacecraft flying in formation. The first spacecraft is a large, thin occulting shield (perhaps hundreds of meters in diameter) with a shaped "pinhole" aperture about 10m in diameter. The second spacecraft is a conventional-quality space telescope (possibly with a 10m primary mirror) which "flies" through the pinhole image of the planetary system to observe the extra-solar planets free from stellar background. In this paper we describe the design of the two spacecraft system. In particular, the shaped-pinhole design utilizes the shaped-pupil coronagraph pioneered for the Terrestrial Planet Finder. In this paper we describe some of the NWO's technology challenges and science opportunities. Additionally, we describe an extension of the design to provide 100km resolution images of extra-solar planets.

Simmons, Willard L.; Cash, Webster C.; Seager, Sara; Wilkinson, Erik; Kasdin, N. Jeremy; Vanderbei, Robert J.; Chow, Naomi; Gralla, Erica; Kleingeld, Johanna

2004-10-01

18

Geochemical studies of the cores of terrestrial planetary bodies  

NASA Astrophysics Data System (ADS)

From the Earth to asteroids, numerous rocky bodies in our solar system are believed to have a metallic core at their center. However, due to the inaccessibility of these cores, fundamental issues, such as the composition of the cores or the processes of core formation and core evolution, are not well known. I have conducted both theoretical and experimental geochemical studies which have improved our understanding of the cores of terrestrial planetary bodies. The radioactive decay of K is an important planetary heat source, but the distribution of K in terrestrial planetary bodies has been debated. My experimental work, which examined the solubility of K in metal, shows no evidence for K to be an important heat source in metallic cores. The element pairs of Ag, Pd and Re, Os have been used to date core formation and core evolution events in our solar system. My experimental determination of the partitioning behavior of these important elements can be used to better understand their distribution in iron meteorites, our only samples of planetary cores. Simple fractional crystallization of a metallic core cannot explain the elemental trends observed within iron meteorite groups. I have developed a crystallization model which suggests slight inhomogeneities and mixing in the molten core were important during core evolution. As a metallic core crystallizes, liquid immiscibility may be encountered, which could significantly affect the subsequent evolution of the core. My experimental work suggests the role of liquid immiscibility during the crystallization of a metallic core is significantly smaller than the published phase diagram implies. These four topics, though each an independent project, together provide insight into the nature of the cores of terrestrial planetary bodies and the processes which affect those cores.

Chabot, Nancy Lynne

1999-11-01

19

Predicting Planets in Known ExtraSolar Planetary Systems III: Forming Terrestrial Planets  

Microsoft Academic Search

Recent results have shown that many of the known extrasolar planetary systems\\u000acontain regions which are stable for both Earth-mass and Saturn-mass planets.\\u000aHere we simulate the formation of terrestrial planets in four planetary systems\\u000a-- 55 Cancri, HD 38529, HD 37124, and HD 74156 -- under the assumption that\\u000athese systems of giant planets are complete and that their

Sean N. Raymond; Rory Barnes; Nathan A. Kaib

2004-01-01

20

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

PubMed

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

Fridlund, Malcolm

2011-02-13

21

Imagined tool-use in near and far space modulates the extra-striate body area.  

PubMed

Active tool-use can result in the incorporation of the tool into the body schema, e.g., the representation of the arm is enlarged according to tool length. This modification even influences the processing of space: using a long tool leads to a remapping of far space as near space. We here further investigate the interaction of the neural representations of the human body, tool use, and spatial domain. Functional magnetic resonance imaging (fMRI) was performed in twelve right-handed healthy individuals while they imagined moving a cylinder towards a target position in far or near space by mentally using either pliers or a joystick. The fMRI data revealed that already the imagined use of preferred tools in near and far space (i.e., pliers in far space, joystick in near space) modulated the neural activity in the extra-striate body area (EBA) located in the occipito-temporal cortex. Moreover, psycho-physical interaction analysis showed that during imagined tool-use the functional connectivity of left EBA to a network representing the near-personal space around the hand was strengthened. This increased functional connectivity is likely to reflect the neural processes underlying the incorporation of the tool into the body schema. Thus, the current data suggest that simulating tool-use modulates the representation of the human body in extra-striate cortex. PMID:22749971

Tomasino, Barbara; Weiss, Peter H; Fink, Gereon R

2012-08-01

22

Estimates of Evaporation From Terrestrial Surface Water Bodies Using the Global Lakes and Wetlands Database  

NASA Astrophysics Data System (ADS)

Land surface modeling has led to significant advances in the understanding the role of the terrestrial hydrologic cycle in the Earth system. However, the representation of land surface of in these modeling approaches suffers from drawbacks such as lack of representation of terrestrial surface water bodies. These water bodies play an important role in the hydrological and biogeochemical cycles and thus should be included in the computation of the hydrologic budget. To emphasize the contribution of surface water bodies towards the total terrestrial evaporative flux, we present global estimates of monthly evaporation rates from lakes, rivers and reservoirs. The identification of lakes, river and reservoirs follows from the Global Lakes and Wetlands Database (Lehner and Doll [2004]). Evaporation is estimated using the Penman formulation, using observed global net radiation and temperature data from Langley Surface Radiation Budget data. We compare our estimates with those from other studies for different hydrologic regions of the world (such as the Mississippi and the Congo basins).

Ortiz, V.; Goteti, G.; Famiglietti, J.

2005-12-01

23

Planning An Efficient Search For ExtraSolar Terrestrial Planets: How To Find Exo-Earths With NWO  

Microsoft Academic Search

The search for exoplanets is an important goal for the Astronomy community in the next decade. We discuss the feasibility of finding terrestrial planets around nearby stars using direct-detection methods. The probability of finding a planet in the habitable zone around a given star depends on its brightness and distance from Earth, the fraction of stellar systems that contain terrestrial

Tiffany M. Glassman; L. Newhart; G. Barber; M. Turnbull

2009-01-01

24

Wet tropospheric delay spatial variability over terrestrial water bodies  

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

25

Planning An Efficient Search For Extra-Solar Terrestrial Planets: How To Find Exo-Earths With NWO  

NASA Astrophysics Data System (ADS)

The search for exoplanets is an important goal for the Astronomy community in the next decade. We discuss the feasibility of finding terrestrial planets around nearby stars using direct-detection methods. The probability of finding a planet in the habitable zone around a given star depends on its brightness and distance from Earth, the fraction of stellar systems that contain terrestrial planets (?Earth), and the characteristics of the observatory. We discuss the available target stars and the completeness of a search for terrestrial exoplanets given different mission constraints. New Worlds Observer (NWO) is a two-spacecraft mission that consists of an external starshade and an UV-optical space telescope, flying in tandem. In this paper, we focus on NWO's ability to complete a feasible observing schedule designed to find and characterize 30 Exo-Earths around nearby stars (if ?Earth = 1). NWO offers the ability to create flexible, adaptable observing schedules to meet a variety of observing goals.

Glassman, Tiffany M.; Newhart, L.; Barber, G.; Turnbull, M.; NWO Study Team

2009-01-01

26

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

PubMed Central

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

2012-01-01

27

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

PubMed

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. PMID:25048944

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

2014-10-01

28

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

NASA Astrophysics Data System (ADS)

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 ? = 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.

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

2014-10-01

29

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

NASA Astrophysics Data System (ADS)

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

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

30

Body mass explains characteristic scales of habitat selection in terrestrial mammals  

PubMed Central

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

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

2011-01-01

31

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

NASA Astrophysics Data System (ADS)

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

Knapmeyer, M.

2003-04-01

32

BODY HYDRATION AND HAEMOLYMPH OSMOLALITY AFFECT FEEDING AND ITS NEURAL CORRELATE IN THE TERRESTRIAL GASTROPOD, UMAX MAXIMUS  

Microsoft Academic Search

SUMMARY 1. When terrestrial slugs (Limax maximus) are dehydrated to 65—70 % of their initial body weight (IBW) their feeding responsiveness is greatly decreased. 2. There is a 90 % decrease in feeding responsiveness when slugs are injected with hyperosmotic mannitol solution that raises the haemolymph osmolality to that of slugs dehydrated to 65-70 % IBW (i.e. 200 mosmolkg\\

CURTIS B. PHIFER; DAVID J. PRIOR

33

TERRESTRIAL LASER SCANNING AND DIGITAL PHOTOGRAMMETRY TECHNIQUES TO MONITOR LANDSLIDE BODIES  

Microsoft Academic Search

Photogrammetry and laser scanning, thanks to significant development in last years, are comparable surveying techniques to generate - without object contact and with a precision commensurate with scale - Digital Terrain Models (DTMs), a fundamental tool to detect, classify and monitoring landslides. The traditional way to survey the territory for landslide detection purposes is aerial or, in some cases, terrestrial

G. Bitelli; M. Dubbini; A. Zanutta

2004-01-01

34

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

NASA Technical Reports Server (NTRS)

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.

Matsui, T.; Mizutani, H.

1978-01-01

35

Effect of metal mixtures (Cd and Zn) on body weight in terrestrial isopods.  

PubMed

The aim of this study was to determine the effect of exposure to cadmium and zinc mixtures on the weight of terrestrial isopods. Experiments were conducted using uncontaminated specimens of P. laevis. The isopods were exposed to various concentrations of cadmium and zinc sulfate in single- and mixed-metal experiments. The mean weight of the unexposed isopods in the control group increased over the 6 weeks of observation. It was concluded that cadmium and zinc, administered separately, had a negative effect on the weight of P. laevis. The weight change (gain or loss) of P. laevis in the exposures to mixtures of cadmium and zinc sulfate were different from those of woodlice where Cd and Zn were administered separately. Combination of the lowest concentrations of Cd and Zn (20 and 1000 mg x kg(-1)) produced a stimulating effect compared to the control. Weight changes of the other two combinations of Cd and Zn (80/4000 and 160/8000 mg x kg(-1)) showed no differences from those of the control, and weight changes of woodlice exposed to Cd and Zn mixtures were mostly the same as those of the control over the 6-week exposure period. It can thus be concluded that mixtures of Cd and Zn have an antagonistic effect on each other in terms of weight of P. laevis. PMID:15195810

Odendaal, J P; Reinecke, A J

2004-04-01

36

Extra Deimensions  

SciTech Connect

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

Chris Hill

2009-10-03

37

Hydrometric Area Local Authority Associated surface water bodies Associated terrestrial ecosystem(s) Area  

Microsoft Academic Search

The major part of the groundwater body is roughly rectangular, with the longer axis oriented E-W. There is a spur leading northwards to about 3 km north of Lorrha. Elevation within the GWB ranges from 30 mAOD along the shore of Lough Derg to 489 mAOD in the Silvermine Mountains in the south of the GWB. Overall, elevation decreases westwards

North Tipperary

38

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

PubMed

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. PMID:15093314

Jones, D T; Hopkin, S P

1998-01-01

39

Body hydration and haemolymph osmolality affect feeding and its neural correlate in the terrestrial gastropod, Limax maximus.  

PubMed

When terrestrial slugs (Limax maximus) are dehydrated to 65-70% of their initial body weight (IBW) their feeding responsiveness is greatly decreased. There is a 90% decrease in feeding responsiveness when slugs are injected with hyperosmotic mannitol solution that raises the haemolymph osmolality to that of slugs dehydrated to 65-70% IBW (i.e. 200 mosmol kg-1 H2O). The duration of the Feeding Motor Programme (FMP) that can be recorded from an isolated CNS-lip preparation is reduced by increasing the osmolality of the saline bathing the preparation. The osmolality of the saline that can modify the FMP corresponds to that of the haemolymph of a slug dehydrated to 65-70% IBW. The pattern of the motor programme is not affected. A gradual increase in saline osmolality which temporally mimics the progressive increase in haemolymph osmolality of a dehydrating slug also causes a decrease in the duration of the FMP. The neural network underlying the FMP appears to adapt to hyperosmotic saline since the duration of FMP bouts gradually returns to normal levels after long-term exposure (6-8 h). PMID:3937884

Phifer, C B; Prior, D J

1985-09-01

40

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

PubMed

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. PMID:24662223

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

2014-09-01

41

Extra Dimensions  

SciTech Connect

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

Hewett, J.

2004-10-05

42

Searching for extra-terrestrial civilizations  

NASA Technical Reports Server (NTRS)

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.

Gindilis, L. M.

1974-01-01

43

Terrestrial Impact Craters: What Can We Learn About the Earth and Other Bodies of Our Solar System? Didactic Activities  

NASA Astrophysics Data System (ADS)

Using the multidisciplinarity character of the planetary sciences, secondary education students can extract information of the terrestrial impact craters with the aid of some mathematic equations and some simple physical concepts.

Uceda, E. R.; de Pablo, M. A.; Castilla, G.

2003-03-01

44

Dynamical Shakeup of Planetary Systems II. N-body simulations of Solar System terrestrial planet formation induced by secular resonance sweeping  

E-print Network

We revisit the "dynamical shakeup" model of Solar System terrestrial planet formation, wherein the whole process is driven by the sweeping of Jupiter's secular resonance as the gas disk is removed. Using a large number of 0.5 Gyr-long N-body simulations, we investigate the different outcomes produced by such a scenario. We confirm that in contrast to existing models, secular resonance sweeping combined with tidal damping by the disk gas can reproduce the low eccentricities and inclinations, and high radial mass concentration, of the Solar System terrestrial planets. At the same time, this also drives the final assemblage of the planets on a timescale of several tens of millions of years, an order of magnitude faster than inferred from previous numerical simulations which neglected these effects, but possibly in better agreement with timescales inferred from cosmochemical data. In addition, we find that significant delivery of water-rich material from the outer Asteroid Belt is a natural byproduct.

E. W. Thommes; M. Nagasawa; D. N. C. Lin

2008-02-05

45

Quantifying The Impact of Extra-Nasal Testing Body Sites for MRSA Colonization at the Time of Hospital or Intensive Care Unit Admission  

PubMed Central

Objective Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of healthcare-associated infections. Recent legislative mandates require nares screening for MRSA at hospital and ICU admission in many states. However, MRSA colonization at extra-nasal sites is increasingly recognized. We conducted a systematic review of the literature to identify the yield of extra-nasal testing for MRSA. Design We searched MEDLINE from January 1966 through January 2012 for articles comparing nasal and extra-nasal screening for MRSA colonization. Studies were categorized by population tested, specifically those admitted to ICUs, and those admitted to hospitals with a high prevalence (?6%) or low prevalence (<6%) of MRSA carriers. Data were extracted using a standardized instrument. Results We reviewed 4,381 abstracts and 735 manuscripts. Twenty-three manuscripts met criteria for analysis (n=39,479 patients). Extra-nasal MRSA screening increased yield by approximately one-third over nares alone. The yield was similar upon ICU admission (weighted average 33%, range 9%–69%), and hospital admission in high (weighted average 37%, range 9–86%) and low prevalence (weighted average 50%, range 0–150%) populations. Comparing individual extra nasal sites, testing the oropharynx increased MRSA detection by 21% over nares alone; rectum by 20%; wounds by 17%; and axilla by 7%. Conclusions Extra-nasal MRSA screening at hospital or ICU admission in adults will increase MRSA detection by one-third compared to nares screening alone. Findings were consistent among subpopulations examined. Extra-nasal testing may be a valuable strategy for outbreak control or in settings of persistent disease, particularly when combined with decolonization or enhanced infection prevention protocols. PMID:23295562

McKinnell, James A.; Huang, Susan S.; Eells, Samantha J.; Cui, Eric; Miller, Loren G.

2013-01-01

46

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

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

47

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

NASA Astrophysics Data System (ADS)

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.

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

2006-01-01

48

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)

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.

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

49

Limitations of terrestrial life.  

NASA Technical Reports Server (NTRS)

Questions of the suitability of other planets in the solar system for terrestrial organisms are discussed. It is found that life forms similar to terrestrial organisms but modified to fit the prevailing conditions could exist on Venus, Mars, and Jupiter. Of these, only in the case of Jupiter is there any evidence that life would have been able to evolve. Life on Jupiter would be restricted to the clouds. It is pointed out that life may have developed on other celestial bodies in forms which are quite dissimilar to terrestrial organisms with regard to their biochemistry.

Molton, P.

1973-01-01

50

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

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

51

Terrestrial sequestration  

ScienceCinema

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.

Charlie Byrer

2010-01-08

52

Terrestrial sequestration  

SciTech Connect

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.

Charlie Byrer

2008-03-10

53

Introduction to Extra Dimensions  

SciTech Connect

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

Rizzo, Thomas G.; /SLAC

2010-04-29

54

Astronomers Reveal Extinct Extra-Terrestrial Fusion Reactor  

NASA Astrophysics Data System (ADS)

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

2004-06-01

55

Reducing Extra-Terrestrial Excavation Forces with Percussion  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

56

Satellite Radiotomography of Ionospheric Responces to Extra-Terrestrial Forcing  

NASA Astrophysics Data System (ADS)

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

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

57

Problem of searching for extra-terrestrial civilizations  

NASA Technical Reports Server (NTRS)

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

Ambartsumyan, V. A.

1974-01-01

58

Extra-terrestrial nuclear power stations : transportation and operation  

E-print Network

Many challenges exist when considering nuclear power to provide electricity for bases on the Moon or Mars, including launch safety, landing safety, deployment, control, and protecting the astronauts from radiation. Examples ...

Kane, Susan Christine

2005-01-01

59

Reducing extra-terrestrial excavation forces with percussion  

NASA Astrophysics Data System (ADS)

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 to a test stand 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 to 700 beats per minute (BPM) were investigated. A reduction in excavation force of as much as 50% was achieved in this experimental investigation.

Mueller, R.; Smith, J. D.; Lippitt, T.; Schuler, J.; Nick, A.

60

A SETI experiment. [Search for Extra Terrestrial Intelligence  

NASA Technical Reports Server (NTRS)

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.

Mclaughlin, W. I.

1986-01-01

61

Terrestrial Planet Finder Coronagraph Observatory summary  

NASA Technical Reports Server (NTRS)

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

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

2005-01-01

62

Phenomenology of Extra Dimensions  

SciTech Connect

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.

Hewett, J.L.; /SLAC

2006-11-07

63

Graviton production from extra dimensions  

E-print Network

Graviton production due to collapsing extra dimensions is studied. The momenta lying in the extra dimensions are taken into account. A $D$-dimensional background is matched to an effectively four-dimensional standard radiation dominated universe. Using observational constraints on the present gravitational wave spectrum, a bound on the maximal temperature at the beginning of the radiation era is derived. This expression depends on the number of extra dimensions, as well as on the $D$-dimensional Planck mass. Furthermore, it is found that the extra dimensions have to be large.

Kerstin E. Kunze; Mairi Sakellariadou

2002-06-21

64

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  

Microsoft Academic Search

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

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

2006-01-01

65

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

E-print Network

In order to test planetary accretion and differentiation scenarios, we integrated a multistage core-mantle differentiation model with N-body accretion simulations. Impacts between embryos and planetesimals 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. The primary constraint on the combined model is the composition of the Earth's primitive mantle, 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 equilibrium pressure and 1-4 parameters that define the starting compositions of primitive bodies. This integrated model has been applied to 6 Grand Tack simulations. Investigations of a broad parameter space indicate that: accretion of Earth was heterogeneous, metal-silicate equilibration pressures increase as accretio...

Rubie, David C; Morbidelli, Alessandro; O'Brien, Dave P; Young, Ed D; de Vries, Jellie; Palme, Herbert; Frost, Daniel J

2014-01-01

66

The Search for other Earths: limits on the giant planet orbits that allow habitable terrestrial planets to form  

E-print Network

Gas giant planets are far easier than terrestrial planets to detect around other stars, and are thought to form much more quickly than terrestrial planets. Thus, in systems with giant planets, the late stages of terrestrial planet formation are strongly affected by the giant planets' dynamical presence. Observations of giant planet orbits may therefore constrain the systems that can harbor potentially habitable, Earth-like planets. We present results of 460 N-body simulations of terrestrial accretion from a disk of Moon- to Mars-sized planetary embryos. We systematically vary the orbital semimajor axis of a Jupiter-mass giant planet between 1.6 and 6 AU, and eccentricity between 0 and 0.4. We find that for Sun-like stars, giant planets inside roughly 2.5 AU inhibit the growth of 0.3 Earth-mass planets in the habitable zone. If planets accrete water from volatile-rich embryos past 2-2.5 AU, then water-rich habitable planets can only form in systems with giant planets beyond 3.5 AU. Giant planets with significant orbital eccentricities inhibit both accretion and water delivery. The majority of the current sample of extra-solar giant planets appears unlikely to form habitable planets.

Sean N. Raymond

2006-05-04

67

Hidden Photons in Extra Dimensions  

E-print Network

Additional U(1) gauge symmetries and corresponding vector bosons, called hidden photons, interacting with the regular photon via kinetic mixing are well motivated in extensions of the Standard Model. Such extensions often exhibit extra spatial dimensions. In this note we investigate the effects of hidden photons living in extra dimensions. In four dimensions such a hidden photon is only detectable if it has a mass or if there exists additional matter charged under it. We note that in extra dimensions suitable masses for hidden photons are automatically present in form of the Kaluza-Klein tower.

Chris J. Wallace; Joerg Jaeckel; Sabyasachi Roy

2013-11-25

68

Terrestrial Ecosystem Adaptation  

E-print Network

Terrestrial Ecosystem Adaptation Steven W. Running and L. Scott Mills RFF REPORT ............................... 16 Expected Future Ecosystem Trends ................................................................................................................................................................ 27 #12; RUNNING AND MILLS 1 Terrestrial Ecosystem Adaptation Steven W. Running and L. Scott

Mills, L. Scott

69

Preliminary Estimate of Production Rates for Terrestrial Cosmogenic 38Ar from Calcium  

Microsoft Academic Search

Cosmogenic 38Ar, dominantly produced from targets of Ca and K (and to a lesser extent from Fe and Ti), has been used in extra-terrestrial studies for decades. Recent measurement of terrestrial cosmogenic 38Ar (Renne et al., 2001) primarily produced by high-energy spallation on calcium has shown potential as a useful addition to stable noble gas cosmogenic geochronology. Terrestrial cosmogenic production

K. B. Knight; P. R. Renne; K. A. Farley

2003-01-01

70

Provenance of the terrestrial planets.  

PubMed

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

Wetherill, G W

1994-01-01

71

Collider searches for extra dimensions  

SciTech Connect

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.

Landsberg, Greg; /Brown U.

2004-12-01

72

In Search of Extra Dimensions  

NASA Astrophysics Data System (ADS)

Quotidian physics problems are solved in a 3-space- plus 1-time-dimensional structure. The seemingly bizzare suggestion that our universe has more physical dimensions is in reality thoroughly plausible. For string theories to make sense, extra dimensions are actually required. Recent developments offer a variety of observables that encode information from a dimensionally richer space-time. An extended experimental program, from table-top to collider and astrophysics, is being developed to explore the intriguing possibility of an extra dimensional world.

Spiropulu, Maria

2001-04-01

73

Origin of the 'Extra Entropy'  

NASA Technical Reports Server (NTRS)

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.

Mushotzky, R.

2008-01-01

74

Particle escape into extra space  

E-print Network

We focus on escape of a spin integer particle the challenge for which is of course that the corresponding field equation contains the second order time derivative and, in general, may be problematic for interpreting the extra-dimensional part of the field as a wave function for the KK modes as it is usually regarded.

Michael Maziashvili

2005-12-29

75

Collider Phenomenology of Extra Dimensions  

SciTech Connect

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

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

2006-03-10

76

Impact erosion of terrestrial planetary atmospheres  

NASA Technical Reports Server (NTRS)

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.

Ahrens, Thomas J.

1992-01-01

77

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...

78

Perirenal extra-adrenal myelolipoma  

PubMed Central

Myelolipomas are rare tumors consisting of both adipose and hematopoietic tissue and are typically found within the adrenal gland. Extra-adrenal involvement is rare, especially those tumors involving the perirenal space and collecting system. We report a case of a patient with an incidentally discovered perirenal mass that was initially concerning for a retroperitoneal liposarcoma. Following surgical resection and pathological analysis, the lesion was found to be an extra-adrenal myelolipoma. This case report and review of the literature demonstrates the importance of the proper work-up and management of perirenal lipoma variants while addressing the issues of tissue biopsy, surgical intervention, and pre- and post-operative surveillance. PMID:25032203

Hajiran, Ali; Morley, Chad; Jansen, Robert; Kandzari, Stanley; Bacaj, Patrick; Zaslau, Stanley; Cardinal, Jon

2014-01-01

79

Perirenal extra-adrenal myelolipoma.  

PubMed

Myelolipomas are rare tumors consisting of both adipose and hematopoietic tissue and are typically found within the adrenal gland. Extra-adrenal involvement is rare, especially those tumors involving the perirenal space and collecting system. We report a case of a patient with an incidentally discovered perirenal mass that was initially concerning for a retroperitoneal liposarcoma. Following surgical resection and pathological analysis, the lesion was found to be an extra-adrenal myelolipoma. This case report and review of the literature demonstrates the importance of the proper work-up and management of perirenal lipoma variants while addressing the issues of tissue biopsy, surgical intervention, and pre- and post-operative surveillance. PMID:25032203

Hajiran, Ali; Morley, Chad; Jansen, Robert; Kandzari, Stanley; Bacaj, Patrick; Zaslau, Stanley; Cardinal, Jon

2014-07-16

80

Extra-ampullary Duodenal Adenocarcinoma.  

PubMed

Extra-ampullary duodenal adenocarcinomas are rare, and when studied, frequently have been grouped with jejunoileal adenocarcinomas. Nevertheless, anecdotal experiences suggest that these neoplasms may present 2 or more distinct phenotypes. To better characterize these neoplasms, we performed a retrospective review of 38 cases with a special focus on the morphologic and immunophenotypic characteristics and their clinicopathologic significance. Our cohort of extra-ampullary duodenal adenocarcinomas was classified on the basis of the morphologic features into gastric type (n=19, 50%), intestinal type (n=14, 37%), pancreaticobiliary type (n=2, 5%), and others (n=3, 8%). Most gastric-type adenocarcinomas (n=18, 95%) developed in the proximal duodenum, whereas the other types were located equally in the proximal and distal duodenum. Intestinal-type dysplasia was present at the periphery of 8 (57%) intestinal-type adenocarcinomas, and 8 (42%) gastric-type adenocarcinoma were associated with gastric-type dysplasia. Gastric foveolar metaplasia (n=12) and Brunner gland hyperplasia (n=10) were exclusively recognized adjacent to gastric-type adenocarcinomas. Notably, intestinal-type histology and the absence of lymph node metastasis were significantly associated with favorable disease-free survival in univariate and multivariate analyses. In summary, this study demonstrated that 2 major subsets of extra-ampullary duodenal adenocarcinoma, intestinal type and gastric type, are associated with distinct histopathologic features and clinical behavior. PMID:25310836

Ushiku, Tetsuo; Arnason, Thomas; Fukayama, Masashi; Lauwers, Gregory Y

2014-11-01

81

New Worlds Observer: system architecture for terrestrial planet finding  

NASA Astrophysics Data System (ADS)

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

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

2007-09-01

82

Terrestrial Impact Structures  

NASA Astrophysics Data System (ADS)

Emphasis is placed on the nature of terrestrial impact structures, the criteria for their identification, and their contribution to constraining formational processes and cratering rate estimates. The relationship of large-scale impact to Earth history is also considered.

Grieve, R. A. F.

83

Terrestrial photovoltaic measurements, 2  

NASA Technical Reports Server (NTRS)

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.

1976-01-01

84

PBS Newshour Extra: AIDS Today  

NSDL National Science Digital Library

AIDS Today, a lesson plan for grades 9-12 form PBS Newshour Extra, "engages students in learning about the AIDS epidemic and focuses them on the importance of HIV prevention, at home and abroad." The lesson plan requires two 90-minute periods to complete and calls for nothing fancier than Internet access for materials. Links to PBS Newshour story transcripts are provided for use with the lesson plan, which consists primarily of questions for class discussion as well as small group and individual learning activities.

2002-01-01

85

Comparative Climatology of Terrestrial Planets  

NASA Astrophysics Data System (ADS)

Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons to a future volume. Our authors have taken on the task to look at climate on the terrestrial planets in the broadest sense possible — by comparing the atmospheric processes at work on the four terrestrial bodies, Earth, Venus, Mars, and Titan (Titan is included because it hosts many of the common processes), and on terrestrial planets around other stars. These processes include the interactions of shortwave and thermal radiation with the atmosphere, condensation and vaporization of volatiles, atmospheric dynamics, chemistry and aerosol formation, and the role of the surface and interior in the long-term evolution of climate. Chapters herein compare the scientific questions, analysis methods, numerical models, and spacecraft remote sensing experiments of Earth and the other terrestrial planets, emphasizing the underlying commonality of physical processes. We look to the future by identifying objectives for ongoing research and new missions. Through these pages we challenge practicing planetary scientists, and most importantly new students of any age, to find pathways and synergies for advancing the field. In Part I, Foundations, we introduce the fundamental physics of climate on terrestrial planets. Starting with the best studied planet by far, Earth, the first chapters discuss what is known and what is not known about the atmospheres and climates of the terrestrial planets of the solar system and beyond. In Part II, Greenhouse Effect and Atmospheric Dynamics, we focus on the processes that govern atmospheric motion and the role that general circulation models play in our current understanding. In Part III, Clouds and Hazes, we provide an in-depth look at the many effects of clouds and aerosols on planetary climate. Although this is a vigorous area of research in the Earth sciences, and very strongly influences climate modeling, the important role that aerosols and clouds play in the climate of all planets is not yet well constrained. This section is intended to stimulate further research on this critical subject. The study of climate involves much more than

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

86

Extra-Axial Cavernous Hemangioma  

PubMed Central

Two patients with extra-axial cavernous hemangioma who presented with headache and oculovisual disturbances were investigated with computed tomography and magnetic resonance imaging. The lesions masqueraded as basal meningioma, but this diagnosis was not supported by magnetic resonance spectroscopy in one patient. Cerebral angiography with embolization was indicated in one patient, but embolization was not justified in the other. Both patients underwent a pterional craniotomy. The lesions were extradural and highly vascular, necessitating excessive transfusion in one patient in whom gross total resection was achieved, and precluding satisfactory removal in the other. There was no mortality. Transient ophthalmoplegia, the only complication in one patient, was due to surgical manipulation of the cavernous sinus; it resolved progressively over 3 months. Extra-axial skull base cavernous hemangiomas are distinct entities with clinical and radiological characteristics that differ from those of intraparenchymal cavernous malformations. They can mimic meningiomas or pituitary tumors. In some cases, magnetic resonance spectroscopy may narrow the differential diagnoses. Surgical resection remains the treatment of choice, facilitated by preoperative embolization to reduce intraoperative bleeding and by the application of the principles of skull base surgery. Fractionated radiotherapy is an alternative in partial or difficult resections and in high-risk and elderly patients. ImagesFigure 1Figure 2Figure 3Figure 4 PMID:17167631

Kanaan, Imad; Jallu, Ashraf; Alwatban, Jehad; Patay, Zoltan; Hessler, Richard

2001-01-01

87

Consumer Control of Terrestrial Ecosystems  

NASA Astrophysics Data System (ADS)

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

Frank, D.

2012-12-01

88

Coreless Terrestrial Exoplanets  

E-print Network

Differentiation in terrestrial planets is expected to include the formation of a metallic iron core. We predict the existence of terrestrial planets that have differentiated but have no metallic core--planets that are effectively a giant silicate mantle. We discuss two paths to forming a coreless terrestrial planet, whereby the oxidation state during planetary accretion and solidification will determine the size or existence of any metallic core. Under this hypothesis, any metallic iron in the bulk accreting material is oxidized by water, binding the iron in the form of iron oxide into the silicate minerals of the planetary mantle. The existence of such silicate planets has consequences for interpreting the compositions and interior density structures of exoplanets based on their mass and radius measurements.

L. Elkins-Tanton; S. Seager

2008-08-13

89

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

ERIC Educational Resources Information Center

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…

Smith, Courtney Michelle

2010-01-01

90

Can Extra Updates Delay Mixing?  

NASA Astrophysics Data System (ADS)

We consider Glauber dynamics (starting from an extremal configuration) in a monotone spin system, and show that interjecting extra updates cannot increase the expected Hamming distance or the total variation distance to the stationary distribution. We deduce that for monotone Markov random fields, when block dynamics contracts a Hamming metric, single-site dynamics mixes in O( n log n) steps on an n-vertex graph. In particular, our result completes work of Kenyon, Mossel and Peres concerning Glauber dynamics for the Ising model on trees. Our approach also shows that on bipartite graphs, alternating updates systematically between odd and even vertices cannot improve the mixing time by more than a factor of log n compared to updates at uniform random locations on an n-vertex graph. Our result is especially effective in comparing block and single-site dynamics; it has already been used in works of Martinelli, Toninelli, Sinclair, Mossel, Sly, Ding, Lubetzky, and Peres in various combinations.

Peres, Yuval; Winkler, Peter

2013-11-01

91

Batteries for terrestrial applications  

SciTech Connect

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

Kulin, T.M.

1998-07-01

92

Terrestrial cosmic rays  

Microsoft Academic Search

This paper reviews the basic physics of those cosmic rays which can affect terrestrial electronics. Cosmic rays at sea level consist mostly of neutrons, protons, pions, muons, electrons, and photons. The particles which cause significant soft fails in electronics are those particles with the strong interaction: neutrons, protons, and pions. At sea level, about 95% of these particles are neutrons.

James F. Ziegler

1996-01-01

93

The terrestrial silica pump.  

PubMed

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. PMID:23300825

Carey, Joanna C; Fulweiler, Robinson W

2012-01-01

94

Terrestrials Dwarf Planets  

E-print Network

Terrestrials Gas Giants Ice Giants Dwarf Planets The Solar System #12;Neptune Uranus Saturn Jupiter & Helium atmospheres. #12;The Dwarf Planets are a new class of Solar System objects defined by the IAU Dwarf planets can have eccentric and highly inclined orbits. #12;The Solar System has 7 Giant Moons

Gaudi, B. Scott

95

GLOBAL TERRESTRIAL CARBON CYCLE  

EPA Science Inventory

There is great uncertainty with regard to the future role of the terrestrial biosphere in the global carbon cycle, arising from both an inadequate understanding of current pools and fluxes as well as the potential effects of rising atmospheric concentrations of CO, on natural eco...

96

INTRODUCED TERRESTRIAL SPECIES (FUTURE)  

EPA Science Inventory

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

97

The Terrestrial Silica Pump  

PubMed Central

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

Carey, Joanna C.; Fulweiler, Robinson W.

2012-01-01

98

NAAP ExtraSolar Planets 1/10 ExtraSolar Planets Student Guide  

E-print Network

Name: NAAP ­ ExtraSolar Planets 1/10 ExtraSolar Planets ­ Student Guide Background Material, Center of Mass, and ExtraSolar Planet Detection. Question 1: Label the positions on the star's orbit is positive when the star is moving away from the earth and negative when the star is moving towards the earth

Farritor, Shane

99

Arsenic Speciation of Terrestrial Invertebrates  

Microsoft Academic Search

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

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

2009-01-01

100

Volcanic ash - Terrestrial versus extraterrestrial  

NASA Technical Reports Server (NTRS)

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.

Okeefe, J. A.

1976-01-01

101

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

NASA Technical Reports Server (NTRS)

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.

Saunders, R. J. F.

1972-01-01

102

Explaining LSND using extra-dimensional shortcuts  

SciTech Connect

We explore the possibility to explain the LSND result in the context of extra-dimensional theories. If sterile neutrinos take shortcuts through extra dimensions, this results in altered neutrino dispersion relations. Active-sterile neutrino oscillations thus are modified and new types of resonances occur.

Hollenberg, Sebastian; Micu, Octavian; Paes, Heinrich [Fakultaet fuer Physik, Technische Universitaet Dortmund, D-44221 Dortmund (Germany); Weiler, Thomas J. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)

2010-02-10

103

Physics of Extra Dimensions Final Report  

SciTech Connect

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.

Csaba Csaki

2007-12-19

104

Cambridge Lectures on Supersymmetry and Extra Dimensions  

Microsoft Academic Search

These lectures on supersymmetry and extra dimensions are aimed at finishing undergraduate and beginning postgraduate students with a background in quantum field theory and group theory. Basic knowledge in general relativity might be advantageous for the discussion of extra dimensions. This course was taught as a 24+1 lecture course in Part III of the Mathematical Tripos in recent years. The

Sven Krippendorf; Fernando Quevedo; Oliver Schlotterer

2010-01-01

105

The Effect of a Planet in the Asteroid Belt on the Orbital Stability of the Terrestrial Planets  

Microsoft Academic Search

If a planetary-mass body were present in the asteroid belt, the orbits of the terrestrial planets and those of the giant planets would be more closely coupled. A greater exchange of angular momentum could affect the stability of the terrestrial planets. Moreover, the planet in the asteroid belt could itself excite terrestrial planet eccentricities. To study these effects, we have

Jack J. Lissauer; Elisa V. Quintana; Eugenio J. Rivera; Martin J. Duncan

2001-01-01

106

Satellite-Terrestrial Network Interoperability  

NASA Technical Reports Server (NTRS)

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

vonDeak, Thomas C.

1998-01-01

107

Collisional Evolution of Terrestrial Planets  

NASA Astrophysics Data System (ADS)

The terrestrial planets are generally thought to have formed via the collisional accumulation of rocky bodies. The characteristics of the planets produced by this process are, to a large degree, determined by their collisional evolution, and their associated differentiation and thermal evolution. Studies of planet formation and planetary collisional evolution have typically been conducted separately. Most works of late-stage planet formation use perfectly inelastic mergers to model collisions (e.g. Agnor, Canup & Levison 1999, Chambers 2001, Levison & Agnor 2003), with certain recognized inadequacies, notably prohibitively large spin angular momentum acquired as a planet grows. To date, studies of the collisional evolution of terrestrial planets has focused on determining the efficacy of single impacts to account for particular planetary characteristics and the formation of satellites (e.g. Benz et al. 1988, Canup & Asphaug 2001, Canup 2004). It has been recognized for some time (Wetherill 1985) that the final characteristics (e.g. spin state, bulk composition, isotopic age) of an accreting planet are determined not by the last or single largest collision but by all of the major collisional encounters in a planet's history (Agnor, Canup & Levison 1999). As demonstrated by our impact models, each major impact changes the silicate to metal ratio, the thermal state, and the spin state, and sets the stage for the subsequent collision. We are studying collisional dynamics and outcomes common to the late stage of terrestrial planet formation. We use smooth particle hydrodynamics model collisions in an effort to identify the range of impact dynamics that allow for accretion (i.e. mass growth instead of mass loss). In our initial study we found that for dynamical environments typical of most late stage accretion models, about half of all collisions between equal mass planetary embryos do not result in accumulation into a larger embryo (Agnor & Asphaug 2004). We will present new results of collisions for a variety of mass ratios and will discuss the cumulative affect of giant impacts and non-accretionary collisions on planetary characteristics (e.g. Mercury's collisional mantle loss and bulk composition, planetary spin states) and the extent to which collisional processes may account for planetary heterogeneity.

Agnor, C.; Asphaug, E.

2004-12-01

108

Terrestrial Exoplanet Light Curves  

E-print Network

The phase or orbital light curves of extrasolar terrestrial planets in reflected or emitted light will contain information about their atmospheres and surfaces complementary to data obtained by other techniques such as spectrosopy. We show calculated light curves at optical and thermal infrared wavelengths for a variety of Earth-like and Earth-unlike planets. We also show that large satellites of Earth-sized planets are detectable, but may cause aliasing effects if the lightcurve is insufficiently sampled.

Eric Gaidos; Nicholas Moskovitz; Darren M. Williams

2005-11-23

109

Immune defence, extra-pair paternity, and sexual selection in birds  

PubMed Central

Secondary sexual characters have been suggested to reliably reflect the ability of individuals to resist debilitating parasites, and females may gain direct or indirect fitness benefits from preferring the most extravagantly ornamented males. Extra-pair paternity provides an estimate of an important component of sexual selection in birds. Species with a high frequency of extra-pair paternity have a variance in realized reproductive success that is greater than the variance in apparent reproductive success, and extra-pair copulations and hence extra-pair paternity by females are often directly associated with the expression of male secondary sexual characters. If sexually dichromatic species have experienced a long period of antagonistic coevolution with their parasites, such species should have evolved larger immune defence organs than sexually monochromatic species. Bird species with sexual dichromatism had larger spleens for their body size than monochromatic species in a comparative analysis. Furthermore, species with a high frequency of extra-pair paternity were sexually dichromatic and had large spleens for their body size. These results are consistent with the hypothesis that females of dichromatic bird species seek extra-pair copulations to obtain indirect fitness benefits in terms of superior resistance of their offspring to virulent parasites.

M?ller, A. P.

1997-01-01

110

Terrestrial Planet Formation in Binary Star Systems  

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

111

Metabolic assessments during extra-vehicular activity  

NASA Astrophysics Data System (ADS)

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.

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

112

Elliptical instability in terrestrial planets and moons  

E-print Network

The presence of celestial companions means that any planet may be subject to three kinds of harmonic mechanical forcing: tides, precession/nutation, and libration. These forcings can generate flows in internal fluid layers, such as fluid cores and subsurface oceans, whose dynamics then significantly differ from solid body rotation. In particular, tides in non-synchronized bodies and libration in synchronized ones are known to be capable of exciting the so-called elliptical instability, i.e. a generic instability corresponding to the destabilization of two-dimensional flows with elliptical streamlines, leading to three-dimensional turbulence. We aim here at confirming the relevance of such an elliptical instability in terrestrial bodies by determining its growth rate, as well as its consequences on energy dissipation, on magnetic field induction, and on heat flux fluctuations on planetary scales. Previous studies and theoretical results for the elliptical instability are re-evaluated and extended to cope with ...

Cébron, David; Moutou, Claire; Gal, Patrice Le; 10.1051/0004-6361/201117741

2012-01-01

113

Job Burnout, Absenteeism, and Extra Role Behaviors  

Microsoft Academic Search

The study aimed to assess absenteeism and extra role behaviors as correlates of job burnout. Employees from a nuclear physics institute (N = 142) completed a survey that included the Maslach Burnout Inventory–General Survey (MBI-GS), self-efficacy, support by colleagues, and workload. Levels of absenteeism and extra role behaviors were provided by company records. Structural Equation Modeling (SEM) analyses were applied to a

Laura Petitta; Michele Vecchione

2011-01-01

114

Terrestrial Planet Growth in Circumbinary Disks  

NASA Technical Reports Server (NTRS)

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

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

2006-01-01

115

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

SciTech Connect

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

Iorio, L., E-mail: lorenzo.iorio@libero.it [Ministero dell'Istruzione, dell'Università e della Ricerca (M.I.U.R.), Fellow of the Royal Astronomical Society (F.R.A.S.), viale Unità d'Italia 68, 70125 Bari (Italy)

2011-05-01

116

Formation of terrestrial planets in a dissipating gas disk with Jupiter and Saturn  

Microsoft Academic Search

We have performed N-body simulations on final accretion stage of terrestrial planets, including the eccentricity and inclination damping effect due to tidal interaction with a gas disk. We investigated the dependence on a depletion time scale of the disk, and the effect of secular perturbations by Jupiter and Saturn. In the final stage, terrestrial planets are formed through coagulation of

Junko Kominami; Shigeru Ida

2004-01-01

117

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

NASA Technical Reports Server (NTRS)

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.

Woon, David E.

2003-01-01

118

TimeBounded Kolmogorov Complexity May Help in Search for Extra Terrestrial Intelligence (SETI)  

E-print Network

, there is a (seeming) problem with this ap­ proach: advanced civilizations, most probably, save communication expenses, the rates with which different civilizations appear and progress are expected to be drastically different. Hence, we can expect both civi­ lizations which are largely behind us in technological and scientific

Ward, Karen

119

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

ERIC Educational Resources Information Center

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…

National Science Teachers Association, Washington, DC.

120

ELF and VLF observations of ionospheric disturbances caused by extra-terrestrial origin  

NASA Astrophysics Data System (ADS)

Very Low Frequency (VLF) radio wave propagates within the Earth-ionosphere waveguide, and hence measurement of the VLF amplitude and phase can be utilized to study physics of phenomena taking place in the lower ionosphere below about 100 km. Observation of Extremely Low Frequency (ELF) radio wave is also a powerful tool to investigate ionospheric phenomena such as lightning. Here we present ELF and VLF observations of ionospheric disturbances caused by extraterrestrial phenomena. Cosmological Gamma-ray bursts has already been known as the origin of ionospheric disturbances. In addition to this, "magnetar" flares has also been recognized to affect the Earth's ionosphere. Ordinary neutron stars possess magnetic fields of about 10^12 Gauss, while magnetars are considered to have extremely strong magnetic fields of about 10^15 G. Some of the magnetars emit short-duration (~0.1 s) gamma-ray bursts repeatedly in active phases, thereby they are named as "Soft Gamma-ray Repeaters (SGRs)". As rare events, SGRs emit exceptionally bright gamma-ray flares "giant flares", whose peak fluxes exceed those of X-class large solar flares by several order of magnitudes. Recent sensitive measurement of ELF and VLF radio waves can observe ionospheric disturbances caused by these short-repeated and giant flares. Namely, we have found that transient ELF radio wave and Schumann resonance were caused by SGR giant flares in 2004. The emission mechanism is still unclear, but similarity of nuclear detonation in 1960's might give some hints to unveil the emission mechanism. Interesting application of VLF measurement of magnetar flare is that we can deduce the gamma-ray spectrum from VLF data. Intensive astronomical X-ray and gamma-ray observations have been performed by satellites in space using very sensitive detectors. Since SGR giant flare emits huge X-ray/gamma-ray flux, such sensitive detectors are affected by severe saturation problems and precise measurement is very difficult. In my presentation, we present how we deduce the photon spectrum from the VLF data. Using Monte Carlo method, we modeled ionization of lower ionosphere, and obtained altitude profile of electron number density. We then utilized Finite-Difference Time Domain (FDTD) method to simulate VLF propagation. The altitude profile and simulated amplitude change differs depending on the energy spectrum. Therefore, by comparing simulation results with the observation, we can infer the source spectrum as an inverse problem.

Tanaka, Y.; Hayakawa, M.; Hobara, Y.; Raulin, J.; Takahashi, Y.; Sato, M.; Terasawa, T.

2013-05-01

121

Comets and Terrestrial Magnetic Storms  

Microsoft Academic Search

A recent theory of the authors attributed terrestrial magnetic storms and auroral displays to the effect of unusual flares of ultra-violet light from the sun falling upon the terrestrial atmosphere. Such flares would be expected to cause changes in comets, and therefore comet changes should be closely connected with magnetic storms. This connection is supported by the evidence brought out

H. B. Maris; E. O. Hulburt

1929-01-01

122

Chapter 8 Terrestrial Biological Resources  

E-print Network

This chapter describes the environmental setting for terrestrial biological resources and the regulatory setting associated with these resources. It also evaluates environmental impacts on terrestrial biological resources that could result from the Lower San Joaquin River (LSJR) and southern Delta water quality (SDWQ) alternatives and, if applicable, offers mitigation measures that

unknown authors

123

Terrestrial Planet Geophysics  

NASA Astrophysics Data System (ADS)

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

Phillips, R. J.

2008-12-01

124

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

NASA Astrophysics Data System (ADS)

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

Datta, Anindya; Patra, Ayon; Raychaudhuri, Sreerup

2014-05-01

125

Cambridge Lectures on Supersymmetry and Extra Dimensions  

E-print Network

These lectures on supersymmetry and extra dimensions are aimed at finishing undergraduate and beginning postgraduate students with a background in quantum field theory and group theory. Basic knowledge in general relativity might be advantageous for the discussion of extra dimensions. This course was taught as a 24+1 lecture course in Part III of the Mathematical Tripos in recent years. The first six chapters give an introduction to supersymmetry in four spacetime dimensions, they fill about two thirds of the lecture notes and are in principle self-contained. The remaining two chapters are devoted to extra spacetime dimensions which are in the end combined with the concept of supersymmetry. Videos from the course lectured in 2006 can be found online at http://www.sms.cam.ac.uk/collection/659537 .

Sven Krippendorf; Fernando Quevedo; Oliver Schlotterer

2010-11-05

126

Universal extra dimensions : life with BLKTs  

NASA Astrophysics Data System (ADS)

In universal extra dimension (UED) models with one compactified extra dimension, a Z2 symmetry, termed KK-parity, ensures the stability of the lightest Kaluza-Klein particle (LKP) which could be a viable dark matter candidate. This symmetry leads to two fixed points in the extra space like direction. In non-minimal versions of UED boundary-localized kinetic terms (BLKT) of same strength at both fixed points induce a new Z2 symmetry which ensures the stability of LKP. The precision of the dark matter measurements severely correlates and restricts the BLKT parameters of gauge bosons and fermions. Furthermore, BLKT parameters of different strengths at the fixed would induce a non-consevation of KK-parity. We examine, in the presence of such terms, single production and decay of Kaluza-Klein excitations of the neutral electroweak gauge bosons in the context of LHC.

Datta, Anindya; Dey, Ujjal Kumar; Raychaudhuri, Amitava; Shaw, Avirup

2014-03-01

127

Cambridge Lectures on Supersymmetry and Extra Dimensions  

E-print Network

These lectures on supersymmetry and extra dimensions are aimed at finishing undergraduate and beginning postgraduate students with a background in quantum field theory and group theory. Basic knowledge in general relativity might be advantageous for the discussion of extra dimensions. This course was taught as a 24+1 lecture course in Part III of the Mathematical Tripos in recent years. The first six chapters give an introduction to supersymmetry in four spacetime dimensions, they fill about two thirds of the lecture notes and are in principle self-contained. The remaining two chapters are devoted to extra spacetime dimensions which are in the end combined with the concept of supersymmetry. Videos from the course lectured in 2006 can be found online at http://www.sms.cam.ac.uk/collection/659537 .

Krippendorf, Sven; Schlotterer, Oliver

2010-01-01

128

Statistical analysis for extra galactic exoplanets  

NASA Astrophysics Data System (ADS)

We present the first statistical analysis on extra galactic stars that could host an exoplanet. We analyze the photometric data of the Ursa Minor Dwarf Spheroidal galaxy, taken by the Isaac Newton Group of Telescopes (INT) and we calculate the probability to detect a planetary transit , based on the stellar characteristics of the statistical sample and the transit detection probability distribution. Our goal is to determine how many possible planets could be detected in the galaxy and therefore create the first catalogue of extra galactic exoplanet host star candidates for future space missions.

Karpouzas, K.

2013-09-01

129

Signatures of extra dimensional sterile neutrinos  

NASA Astrophysics Data System (ADS)

We study a large extra dimension model with active and sterile Dirac neutrinos. The sterile neutrino masses stem from compactification of an extra dimension with radius R and are chosen to have masses around eV or keV, in order to explain short-baseline anomalies or act as warm dark matter candidates. We study the effect of the sterile neutrino Kaluza-Klein tower in short-baseline oscillation experiments and in the beta spectrum as measurable by KATRIN-like experiments.

Rodejohann, Werner; Zhang, He

2014-10-01

130

A Thermal Graviton Background from Extra Dimensions  

E-print Network

Inflationary cosmology predicts a low-amplitude graviton background across a wide range of frequencies. This Letter shows that if one or more extra dimensions exist, the graviton background may have a thermal spectrum instead, dependent on the fundamental scale of the extra dimensions. The energy density is shown to be significant enough that it can affect nucleosynthesis in a substantial way. The possibility of direct detection of a thermal graviton background using the 21-cm hydrogen line is discussed. Alternative explanations for the creation of a thermal graviton background are also examined.

E. R. Siegel; J. N. Fry

2005-03-07

131

NewsHour Extra: Addressing Health Mysteries  

NSDL National Science Digital Library

In this PBS NewsHour Extra lesson plan, students take an in-depth look at the SARS epidemic, with a particular focus on pan-national public health administration. A NewsHour interview with Dr. David Heyman, Director for Communicable Diseases at the World Health Organization (WHO), forms the basis of the exercise (video, audio, and transcript available). A NewsHour Extra story on SARS provides additional material. The site also offers ideas for homework and extension activities, each designed to help students explore and understand the process by which organizations like WHO tackle new disease outbreaks.

Dufour, Joanne.

132

Supersymmetry and Vector-like Extra Generation  

E-print Network

Within the framework of supersymmetry, the particle content is extended in a way that each Higgs doublet is in a full generation. Namely in addition to ordinary three generations, there is an extra vector-like generation, and it is the extra slepton SU(2)_L doublets that are taken to be the two Higgs doublets. R-parity violating interactions contain ordinary Yukawa interactions. Breaking of supersymmetry and gauge symmetry are analyzed. Fermion and boson spectra are calculated. Phenomenological constraints and relevant new physics at Large Hadron Collider are discussed.

Chun Liu

2009-07-17

133

Microscopic Primordial Black Holes and Extra Dimensions  

SciTech Connect

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.

Conley, John A.; Wizansky, Tommer

2006-11-15

134

Particle physics probes of extra spacetime dimensions  

Microsoft Academic Search

The possibility that spacetime extends beyond the familiar 3 + 1 dimensions has intrigued physicists for a century. The consequences of a dimensionally richer spacetime would be profound. Recently, new theories with higher-dimensional spacetimes have been developed to resolve the hierarchy problem in particle physics. The distinct predictions of these scenarios allow experiment to probe the existence of extra dimensions

Joanne Hewett; Maria Spiropulu

2002-01-01

135

Finance Division EXTRA MILE AWARD PROGRAM  

E-print Network

Finance Division EXTRA MILE AWARD PROGRAM Nomination Form Instructions Any fulltime or parttime permanent or temporary SPA employee within the Finance Division who works 20 or more provided. The seven major departments within the Finance Division to choose from are described below

Crews, Stephen

136

Probing Extra Dimensions with Neutrino Oscillations  

NASA Astrophysics Data System (ADS)

We consider a model where sterile neutrinos can propagate in a large compactified extra dimension ( a) giving rise to Kaluza-Klein (KK) modes and the Standard Model left-handed neutrinos are confined to a 4-dimensional spacetime brane. The KK modes mix with the standard neutrinos modifying their oscillation pattern. We examine current experiments in this framework obtaining stringent limits on a.

Machado, P. A. N.; Nunokawa, H.; Zukanovich Funchal, R.

2011-08-01

137

Graviton Cosmology in Universal Extra Dimensions  

E-print Network

In models of universal extra dimensions, gravity and all standard model fields propagate in the extra dimensions. Previous studies of such models have concentrated on the Kaluza-Klein (KK) partners of standard model particles. Here we determine the properties of the KK gravitons and explore their cosmological implications. We find the lifetimes of decays to KK gravitons, of relevance for the viability of KK gravitons as dark matter. We then discuss the primordial production of KK gravitons after reheating. The existence of a tower of KK graviton states makes such production extremely efficient: for reheat temperature T_RH and d extra dimensions, the energy density stored in gravitons scales as T_RH^{2+3d/2}. Overclosure and Big Bang nucleosynthesis therefore stringently constrain T_RH in all universal extra dimension scenarios. At the same time, there is a window of reheat temperatures low enough to avoid these constraints and high enough to generate the desired thermal relic density for KK WIMP and superWIMP dark matter.

Jonathan L. Feng; Arvind Rajaraman; Fumihiro Takayama

2003-07-31

138

Massive Neutrinos in a Warped Extra Dimension  

Microsoft Academic Search

The Randall-Sundrum I (RS1) model of a warped extra dimension provides a natural candidate solution to the hierarchy problem between the Planck and weak scales. Coincidentally, the theoretical development of such 'braneworld' models in the late 1990s coincided with the experimental veriflcation of nonzero neutrino masses. This presents another hierarchy problem: why are neutrino masses vanishingly small compared to the

Philip Tanedo

2007-01-01

139

Adapting the GISS Climate GCM to Model Extra-Solar Climate Regimes  

NASA Astrophysics Data System (ADS)

Hundreds of extra-solar planets have been discovered by NASA's Kepler mission, some potentially habitable, most exhibiting extremes in climate beyond current modeling experience. Zero-order assessment of the stellar type and the planet's distance from the star serves to identify the ballpark of whether silicon dioxide is likely to be in gaseous or liquid phase in the planet's atmosphere, or a part of the solid planetary ground surface. A lot of first-order modeling would involve assessing the chemical limitations to establish the likely chemical composition of the planetary atmosphere. For a more detailed analysis of the prevailing climate on an extra-solar planet a 3-D global climate model would be required. We begin the Extra-Solar Climate Model development by starting the with GISS Climate GCM by having key model parameters be expressed in physics based terms rather than Earth specific parameters. Examples of such key parameters are: the Planet's mass and radius, mass and composition of the atmosphere, Star-Planet distance, rotation rate and orbital parameters, stellar spectral distribution, land topography, and land-ocean distribution. These are parameters that are more or less straight forward to redefine for extra-solar conditions that are not greatly different for what may be considered as the ';habitable' zone. We present extreme climate simulations ranging from snowball Earth conditions to near-runaway greenhouse conditions. The objective of this modeling study is the development of a more physically based climate model that will be adaptable for assessing habitable climate regimes on newly discovered extra-solar planets, and will also facilitate the study terrestrial climate system analysis in paleoclimate applications.

Lacis, A. A.

2013-12-01

140

The rise and fall of extra dimensions  

NASA Astrophysics Data System (ADS)

The Standard Model, as an effective theory, provides an extremely good description of particle physics. It is however plagued with various naturalness problems. The most serious one is the extreme sensitivity of the Higgs mass to high energy physics. This is seen as a very strong indication that new physics is needed at TeV energies to stabilize the weak scale. For a long time, the options for this new physics have been limited to supersymmetry and technicolor. In the last few years, extra dimensions and branes, previously used mainly by string theorists, became a common tool in beyond the Standard Model model building. In the second chapter of this dissertation, we present a formalism for writing supersymmetric extra-dimensional theories in term of 4D superfields. This helps in the construction of supersymmetric brane world models. More recently, it has been discovered that extra dimensions can be "deconstructed", and extra-dimensional models can be turned into four dimensional ones using locality in "theory space", an abstract space of gauge group factors. This was used to provide UV completions of extra dimensional theories and led to the discovery of new four dimensional model building possibilities. In particular, it led to the development of little Higgs theories, a new approach to the hierarchy problem where the Higgs is a pseudo-Goldstone boson. These models are the only fully realistic and natural alternative to supersymmetry that stabilizes the weak scale using weakly coupled physics. In the third chapter of the dissertation, we study little Higgs models based on the deconstruction of a torus. In the fourth chapter, we generalize and present the rules for building little Higgs theories using topological properties of general theory spaces. Finally in the fifth chapter, we discuss the UV completion of six dimensional gauge theories using a strongly coupled deconstructed torus.

Gregoire, Thomas

141

USING TERRESTRIAL PLANTS IN BIOMONITORING  

EPA Science Inventory

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

142

Radiocarbon dating of terrestrial carbonates  

USGS Publications Warehouse

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.

Pigati, Jeffrey S.

2014-01-01

143

GEOLogic: Terrestrial and Jovian Planets  

NSDL National Science Digital Library

In this two-part example, students are given clues about properties about the terrestrial and Jovian planets respectively and asked to match up the planet with the correct equatorial radius, mean orbital velocity, and period of rotation.

Guertin, Laura

144

On the early global melting of the terrestrial planets  

NASA Technical Reports Server (NTRS)

Attention is given to all the mechanisms currently known which might have been responsible for the melting of the moon. A comparison is conducted of the terrestrial planets and the moon, taking into account the conditions in the early solar system as a function of time. The assumption is made that the terrestrial planets and the moon all reached sizes comparable to their present sizes at the same time, so that the same heating mechanisms were operating on all of the bodies when their early crusts were formed. A chronology of the early solar system is established in order to evaluate the time periods during which each of the mechanisms might have been active. If the moon and planets formed within 2,000,000 years after the formation of the protosun, the conclusion appears inescapable that all of the terrestrial planets melted.

Hostetler, C. J.; Drake, M. J.

1980-01-01

145

Structure and evolution of the terrestrial planets  

NASA Astrophysics Data System (ADS)

Geo-scientific planetary research of the last 25 years has revealed the global structure and evolution of the terrestrial planets Moon, Mercury, Venus and Mars. The evolution of the terrestrial bodies involves a differentiation into heavy metallic cores, Fe-and Mg-rich silicate mantles and light Ca, Al-rich silicate crusts early in the history of the solar system. Magnetic measurements yield a weak dipole field for Mercury, a very weak field (and local anomalies) for the Moon and no measurable field for Venus and mars. Seismic studies of the Moon show a crust-mantle boundary at an average depth of 60 km for the front side, P- and S-wave velocities around 8 respectively 4.5 km s-1 in the mantle and a considerable S-wave attenuation below a depth of 1000 km. Satellite gravity permits the study of lateral density variations in the lithosphere. Additional contributions come from photogeology, orbital particle, x-and ?-ray measurements, radar and petrology. The cratered surfaces of the smaller bodies Moon and Mercury have been mainly shaped by meteorite impacts followed by a period of volcanic flows into the impact basins until about 3×109 yr before present. Mars in addition shows a more developed surface. Its northern half is dominated by subsidence and younger volcanic flows. It even shows a graben system (rift) in the equatorial region. Large channels and relics of permafrost attest the role of water for the erosional history. Venus, the most developed body except Earth, shows many indications of volcanism, grabens (rifts) and at least at northern latitudes collisional belts, i.e. mountain ranges, suggesting a limited plate tectonic process with a possible shallow subduction.

Janle, P.; Meissner, R.

1986-06-01

146

Workshop on Oxygen in the Terrestrial Planets  

NASA Technical Reports Server (NTRS)

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

2004-01-01

147

Out-of-body experience and autoscopy of neurological origin  

Microsoft Academic Search

Summary During an out-of-body experience (OBE), the experient seems to be awake and to see his body and the world from a location outside the physical body. A closely related experience is autoscopy (AS), which is charac- terized by the experience of seeing one's body in extra- personal space. Yet, despite great public interest and many case studies, systematic neurological

Olaf Blanke; Theodor Landis; Laurent Spinelli; Margitta Seeck

2004-01-01

148

Majorana dark matter in warped extra dimensions  

NASA Astrophysics Data System (ADS)

Generic extensions of the Standard Model that respect baryon and lepton numbers have accidentally stable particles. Typical examples are the lightest exotic neutral fermion, or "neutralino," and fields with nontrivial lepton and baryon charges. In this paper we identify the accidentally stable neutralino with the dark matter, and discuss its phenomenology in the framework of warped extra dimensions. We find that annihilation into other Kaluza-Klein resonances is often allowed and very efficient. The observed dark matter abundance may then be obtained with couplings of order unity and a compactification scale above the TeV. Light dark matter is also possible in the presence of unsuppressed couplings to the Higgs boson. In this latter case dark matter direct detection experiments will soon be able to probe a significant portion of the parameter space. This analysis suggests that dark matter is a natural feature of realistic models with warped extra dimensions.

Vecchi, Luca

2014-07-01

149

Deformed brane with finite extra dimension  

NASA Astrophysics Data System (ADS)

We construct a deformed brane solution generated by a double-kink scalar field and a dilaton scalar field. In this brane scenario the extra dimension is finite, which is due to the introduction of the dilaton field with a special form. The finity of the extra dimension will result in the localization of the zero mode for the vector fields, while the localization of the Kalb-Ramond fields depends on the coupling to the dilaton. For the fermion fields, with different values of the dilaton-fermion coupling constant, there are three types of the effective potential for the fermion Kaluza-Klein modes. Moreover, we investigate the effect of the deformation of the brane on the localization, and find that the number of the resonances will increase with the distances of the two sub-branes.

Liu, Yu-Xiao; Fu, Chun-E.; Guo, Heng; Li, Hai-Tao

2012-04-01

150

Stellar evolution and large extra dimensions  

E-print Network

We discuss in detail the information on large extra dimensions which can be derived in the framework of stellar evolution theory and observation. The main effect of large extra dimensions arises from the production of the Kaluza-Klein (KK) excitations of the graviton. The KK-graviton and matter interactions are of gravitational strength, so the KK states never become thermalized and always freely escape. In this paper we first pay attention to the sun. Production of KK gravitons is incompatible with helioseismic constraints unless the 4+n dimensional Planck mass M_s exceeds 300 Gev/c^2. Next we show that stellar structures in their advanced phase of H burning evolution put much more severe constraints, M_s > 3-4 TeV/c^2, improving on current laboratory lower limits.

S. Cassisi; V. Castellani; S. Degl'Innocenti G. Fiorentini; B. Ricci

2000-02-08

151

Extra-corporeal shock wave lithotripsy.  

PubMed Central

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

Pemberton, J.

1987-01-01

152

Extra gauge symmetries in BHT gravity  

E-print Network

We study the canonical structure of the Bergshoeff-Hohm-Townsend massive gravity, linearized around a maximally symmetric background. At the critical point in the space of parameters, defined by $\\Lambda_0/m^2=-1$, we discover an extra gauge symmetry, which reflects the existence of the partially massless mode. The number of the Lagrangian degrees of freedom is found to be 1. We show that the canonical structure of the theory at the critical point is unstable under linearization.

M. Blagojevi?; B. Cvetkovi?

2011-03-11

153

Extra gauge symmetries in BHT gravity  

NASA Astrophysics Data System (ADS)

We study the canonical structure of the Bergshoeff-Hohm-Townsend massive gravity, linearized around a maximally symmetric background. At the critical point in the space of parameters, defined by ? 0/ m 2 = -1, we discover an extra gauge symmetry, which reflects the existence of the partially massless mode. The number of the Lagrangian degrees of freedom is found to be 1. We show that the canonical structure of the theory at the critical point is unstable under linearization.

Blagojevi?, M.; Cvetkovi?, B.

2011-03-01

154

Extra gauge symmetries in BHT gravity  

E-print Network

We study the canonical structure of the Bergshoeff-Hohm-Townsend massive gravity, linearized around a maximally symmetric background. At the critical point in the space of parameters, defined by $\\Lambda_0/m^2=-1$, we discover an extra gauge symmetry, which reflects the existence of the partially massless mode. The number of the Lagrangian degrees of freedom is found to be 1. We show that the canonical structure of the theory at the critical point is unstable under linearization.

Blagojevi?, M

2011-01-01

155

Metastable gravitons and infinite volume extra dimensions  

Microsoft Academic Search

We address the issue of whether extra dimensions could have an infinite volume and yet reproduce the effects of observable four-dimensional gravity on a brane. There is no normalizable zero-mode graviton in this case, nevertheless correct Newton's law can be obtained by exchanging bulk gravitons. This can be interpreted as an exchange of a single metastable 4D graviton. Such theories

G. Dvali; G. Gabadadze; M. Porrati

2000-01-01

156

Relaxing Cosmological Constraints on Large Extra Dimensions  

E-print Network

We reconsider cosmological constraints on extra dimension theories from the excess production of Kaluza-Klein gravitons. We point out that, if the normalcy temperature is above 1 GeV, then graviton states produced at this temperature will decay early enough that they do not affect the present day dark matter density, or the diffuse gamma ray background. We rederive the relevant cosmological constraints for this scenario.

Cosmin Macesanu; Mark Trodden

2004-07-20

157

Dimensional reduction without continuous extra dimensions  

SciTech Connect

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.

Chamseddine, Ali H. [American University of Beirut, Physics Department, Beirut, Lebanon and I.H.E.S. F-91440 Bures-sur-Yvette (France)] [American University of Beirut, Physics Department, Beirut, Lebanon and I.H.E.S. F-91440 Bures-sur-Yvette (France); Froehlich, J.; Schubnel, B. [ETHZ, Mathematics and Physics Departments, Zuerich (Switzerland)] [ETHZ, Mathematics and Physics Departments, Zuerich (Switzerland); Wyler, D. [Institute of Theoretical Physics, University of Zuerich (Switzerland)] [Institute of Theoretical Physics, University of Zuerich (Switzerland)

2013-01-15

158

Extra Large Temporal Tunnel Cataract Extraction [ETCE  

PubMed Central

Purpose: To determine the outcomes of extra large temporal sclero-corneal tunnel incision Cataract Surgery. Materials and Methods: This consecutive case series of eyes undergoing temporal tunnel cataract extraction with tunnel length of 8 to 10 mm was identified retrospectively. Surgical procedure details, follow up, complications, visual and astigmatic outcomes at 6wks were recorded and analysed. Results: Ninety six eyes with extra large tunnel incision were identified for analysis from a dataset of 670 manual small incision cataract surgery cases. 58% eyes had NO5 or denser cataracts. Intraoperative complications included, tunnel related problems (1 eye, 1.04%), bleeding into Anterior Chamber (10 eyes, 10.4%), Posterior Capsular Rent (2 eyes, 2.1%). Early postoperative complications included striate keratopathy (7 eyes, 7.3%). The mean Best Corrected Visual Acuity was 6/7.5 (0.1 logMAR) and 98% cases had Best Corrected Visual Acuity of 6/12 (0.3 logMAR) or better at 6wk. The aggregate Surgically Induced Astigmatism was 0.32D at 850. Conclusion: Extra Large Tunnel of length 8 to 10 mm can be self sealing with low SIA. The complication rates and visual outcomes of ETCE are comparable to those of conventional MSICS. This method can be valuable in complicated cases and during learning period. PMID:25386505

U., Vivekanand

2014-01-01

159

Noncommutative Inspired Black Holes in Extra Dimensions  

SciTech Connect

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

Rizzo, Thomas G.

2006-06-07

160

Who Does Extra-Credit Work in Introductory Science Courses?  

ERIC Educational Resources Information Center

On the first day of classes, 81% of students in an introductory biology course claimed that they would submit extra-credit work if given the opportunity. When given two chances for extra-credit work, fewer than one-fourth of students submitted one or both assignments. Students who submitted extra-credit work were more likely to attend class,…

Moore, Randy

2005-01-01

161

Utilization of the terrestrial cyanobacteria  

NASA Astrophysics Data System (ADS)

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

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

162

Groundwater and Terrestrial Water Storage  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

163

Basaltic volcanism in terrestrial planets  

NASA Technical Reports Server (NTRS)

A prescription is presented of a 3-year experimental project designed to encourage a selected group of earth scientists to think on a Solar System scale rather than a terrestrial, lunar, or martian scale. Basaltic volcanism was the process selected because it manifests itself widely in the inner Solar System and because it seemed more cleanly separable from other geological problems than other processes considered. Studies in ten areas are to illuminate all aspects of the mechanics and chronology of the generation and eruption of basaltic lavas in the terrestrial planets. Attention is given to individual team reports related to the various areas.

Wood, J. A.

1977-01-01

164

Space Physics and Terrestrial Effects  

NSDL National Science Digital Library

This curriculum guide is intended for high school teachers who are teaching solar physics, especially the effects of solar activity on terrestrial planets. The chapters discuss stellar evolution, the structure of the sun, studying the sun, and solar and terrestrial interactions. Lab activities provided include: building a spectroscope, energy transport within the sun, measuring the solar constant, luminosity of the sun and stars, seeing different wavelengths, the Earth-Sun orientation, the effect of the solar wind on the geomagnetic field, determining the rotation period of the sun, and radiation hazards in space.

2005-05-23

165

Terrestrial adaptations in the hands of Equatorius africanus revisited  

Microsoft Academic Search

Interpretations of the postcranial anatomy of East African early and middle Miocene large-bodied hominoids (e.g., Proconsul, Afropithecus, Turkanapithecus, Nacholapithecus) have suggested that these diverse primates utilized positional behaviors dominated by arboreal quadrupedalism. Preliminary descriptions of the Equatorius africanus partial skeleton (KNM-TH 28860) and other forelimb specimens, however, have argued that this animal relied more on terrestrial locomotion compared to its

Biren A. Patel; Randall L. Susman; James B. Rossie; Andrew Hill

2009-01-01

166

Extra-pancreatic effects of incretin-based therapies.  

PubMed

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

Gallwitz, Baptist

2014-11-01

167

Robust frameless stereotactic localization in extra-cranial radiotherapy  

SciTech Connect

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

Riboldi, Marco; Baroni, Guido; Spadea, Maria Francesca; Bassanini, Fabio; Tagaste, Barbara; Garibaldi, Cristina; Orecchia, Roberto; Pedotti, Antonio [TBMLab, Department of Bioengineering, Politecnico di Milano University, P.za Leonardo da Vinci 32, Milan 20133 (Italy); Medical Physics, European Institute of Oncology, Via Ripamonti 435, Milan 20141 (Italy); Radiotherapy Division, European Institute of Oncology, Via Ripamonti 435, Milan 20141 (Italy) and Instituto di Scienze Radiologiche, Polo Universitario H S. Paolo, Via Rudini 8, Milan 20142 (Italy); TBMLab, Department of Bioengineering, Politecnico di Milano University, P.za Leonardo da Vinci 32, Milan 20133 (Italy)

2006-04-15

168

LHC bounds on large extra dimensions  

NASA Astrophysics Data System (ADS)

We derive new dominant bounds on the coefficient of the effective operator generated by tree-level graviton exchange in large extra dimensions from pp ? jj data at LHC: M T > 2.1 TeV (ATLAS after 3.1/pb of integrated luminosity), M T > 3.4 TeV (CMS after 36/pb), M T > 3.2 TeV (ATLAS after 36/pb). We clarify the role of on-shell graviton exchange and compare the full graviton amplitude to data, setting bounds on the fundamental quantum-gravity scale.

Franceschini, Roberto; Paolo Giardino, Pier; Giudice, Gian F.; Lodone, Paolo; Strumia, Alessandro

2011-05-01

169

Direct imaging of extra-solar planets  

SciTech Connect

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.

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

1997-03-01

170

About Mass, CP and Extra Dimensions  

E-print Network

We discuss the notion of mass, mostly for fermions, and its relation to the breaking of CP invariance, the natural symmetry of gauge interactions. In a first model, we show how compactification on a Vortex in 2 extra dimensions leads to a replication of generations in 3+1, with challenging mass patterns, and testable consequences in flavour-changing neutral currents (family-number conserving), both at low energies and at future colliders. In different model, we show how CP violation can result from compactification from 4+1 to 3+1 dimensions.

J. -M. Frère

2006-09-05

171

Terrestrial Behavior of Ateles spp  

Microsoft Academic Search

Spider monkeys (Ateles spp.) are well known for their highly arboreal lifestyle, spending much of their time in the highest levels of the canopy and rarely venturing to the ground. To investigate terrestriality by Ateles and to illuminate the conditions under which spider monkeys venture to the ground, we analyzed ad libitum data from 5 study sites, covering 2 species

Christina J. Campbell; Filippo Aureli; Colin A. Chapman; Gabriel Ramos-Fernández; Kim Matthews; Sabrina E. Russo; Scott Suarez; Laura Vick

2005-01-01

172

Ionospheres of the terrestrial planets  

Microsoft Academic Search

The theory and observations relating to the ionospheres of the terrestrial planets Venus, the earth and Mars are reviewed. Emphasis is placed on comparing the basic differences and similarities between the planetary ionospheres. The review covers the plasma and electric-magnetic field environments that surround the planets, the theory leading to the creation and transport of ionization in the ionspheres, the

R. W. Schunk; A. F. Nagy

1980-01-01

173

Formation of the terrestrial planets from planetesimals  

NASA Technical Reports Server (NTRS)

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

Wetherill, George W.

1991-01-01

174

A village known for extra births.  

PubMed

This article identifies Baimiao village in Baimiao Town, Linquan County, Anhui Province, China, as a administrative unit without a strong family planning program and with extra births. Baimiao village is comprised of 5 sub-villages and 2471 persons, of whom 414 are women of childbearing age. During 1992-97 there were 321 newborns, of which 124 were 1st-parity births and 137 were 2nd-parity births. 47 were unplanned 3rd-parity births, 9 were 4th-parity births, 3 were 5th-parity births, and 1 was a 6th-parity birth. About 50% of the newborns were unplanned pregnancies. After the only village family planning worker left, the village did not have a replacement, and data recording became inaccurate. People concealed births and underreported unplanned births. Higher fertility was encouraged by the poor example set by Party members and cadres in the village who had out-of-quota births. Among the 39 Party members and cadres in the village, 23 had unplanned births and some had third parity births. After the mass media exposed the extra births occurring in the village among Party members and the community, penalties and discipline were given to Party members and cadres. Penalties included loss of their jobs or banishment from the Communist party. PMID:12293905

Zhu, H

1998-06-01

175

Tidal Heating of Extra-Solar Planets  

E-print Network

Extra-solar planets close to their host stars have likely undergone significant tidal evolution since the time of their formation. Tides probably dominated their orbital evolution once the dust and gas had cleared away, and as the orbits evolved there was substantial tidal heating within the planets. The tidal heating history of each planet may have contributed significantly to the thermal budget that governed the planet's physical properties, including its radius, which in many cases may be measured by observing transit events. Typically, tidal heating increases as a planet moves inward toward its star and then decreases as its orbit circularizes. Here we compute the plausible heating histories for several planets with measured radii, using the same tidal parameters for the star and planet that had been shown to reconcile the eccentricity distribution of close-in planets with other extra-solar planets. Several planets are discussed, including for example HD 209458 b, which may have undergone substantial tidal heating during the past billion years, perhaps enough to explain its large measured radius. Our models also show that GJ 876 d may have experienced tremendous heating and is probably not a solid, rocky planet. Theoretical models should include the role of tidal heating, which is large, but time-varying.

Brian Jackson; Richard Greenberg; Rory Barnes

2008-02-29

176

The Extra-Zodiacal Explorer (EZE)  

NASA Astrophysics Data System (ADS)

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.

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

2012-01-01

177

Long-term solar-terrestrial observations  

NASA Technical Reports Server (NTRS)

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.

1988-01-01

178

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

NASA Astrophysics Data System (ADS)

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).

Tiengo, Andrea

179

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

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

180

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

PubMed

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

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

2011-11-01

181

Jan 23 Terrestrial Forest Biomes of the World Terrestrial Forest Biomes of the World  

E-print Network

Jan 23 Terrestrial Forest Biomes of the World #12;Terrestrial Forest Biomes of the World Chapin et al. 2011. Fig 2.24 #12;Terrestrial Forest Biomes of the World Chapin et al. 2011. Fig 2.24 Biome Wildlife Fund Terrestrial Biomes and Biogeographic Realms of the World #12;Climate Controls on Biomes

Hansen, Andrew J.

182

Body Weight  

MedlinePLUS

... to medicines, thyroid problems, heart failure, and kidney disease. Good nutrition and exercise can help in losing weight. Eating extra calories within a well-balanced diet and treating any underlying medical problems can help to add ...

183

Error analysis of penetrator impacts on bodies without atmospheres  

NASA Technical Reports Server (NTRS)

Penetrators are missile shaped objects designed to implant electronic instrumentation in various of surface materials with a nominal impact speed around 150 m/sec. An interest in the application of this concept to in situ subsurface studies of extra terrestrial bodies and planetary satellites exists. Since many of these objects do not have atmospheres, the feasibility of successfully guiding penetrators to the required near-zero angle-of-attack impact conditions in the absence of an atmosphere was analyzed. Two potential targets were included, i.e., the moon and Mercury and several different penetrator deployment modes were involved. Impact errors arising from open-loop and closed-loop deployment control systems were given particular attention. Successful penetrator implacement requires: (1) that the impact speed be controlled, nominally to 150 m/sec, (2) that the angle of attack be in range 0 deg - 11 deg at impact, and (3) that the impact flight path angle be with 15 deg of vertical.

Davis, D. R.

1975-01-01

184

Terrestrial photovoltaic collector technology trends  

NASA Technical Reports Server (NTRS)

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.

Shimada, K.; Costogue, E.

1984-01-01

185

Global Climate Models of the Terrestrial Planets  

NASA Astrophysics Data System (ADS)

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

Forget, F.; Lebonnois, S.

186

Lepton Flavor Violation in Extra Dimension Models  

E-print Network

Models involving large extra spatial dimension(s) have interesting predictions on lepton flavor violating processes. We consider some 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, $\\mu\\ra e \\gamma$ and $\\mu\\ra 3e$ 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 $\\mu\\ra e \\gamma$ like rare process is much smaller than the ones of $\\mu\\ra 3e$ like processes. This is in sharp contrast to most of the traditional wisdom based on four dimensional gauge models. Moreover, some rare tau decays are more promising than the rare muon decays.

We-Fu Chang; John N. Ng

2005-01-18

187

MATE GUARDING AND EXTRA-PAIR PATERNITY IN NORTHERN CARDINALS  

Microsoft Academic Search

We studied patterns of mate guarding and paternity in 21 pairs of Northern Cardinals (Cardinalis cardinalis) nesting in~central_Kentucky. DbJA fingerprinting revealed that five of 37 nestlinas (13.5%) resulted from extra-pair fertilizations (EPFs). Of 19 broods sampled, three (16%)-bad at least one extra-pair young. Although our observations of male cardinals making extra-territorial movements suggest that some males in the population may

DAVID F. WESTNEAT

188

Compact extra dimensions in cosmologies with f(T) structure  

NASA Astrophysics Data System (ADS)

The presence of compact extra dimensions in cosmological scenarios in the context of f(T)-like gravities is discussed. For the case of toroidal compactifications, the analysis is performed in an arbitrary number of extra dimensions. Spherical topologies for the extra dimensions are then carefully studied in six and seven spacetime dimensions, where the proper vielbein fields responsible for the parallelization process are found.

Fiorini, Franco; González, P. A.; Vásquez, Yerko

2014-01-01

189

Chemical impurity produces extra compound eyes and heads in crickets  

SciTech Connect

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

Walton, B.T.

1981-04-03

190

Alien Terrestrial Invertebrates of Europe  

Microsoft Academic Search

Unlike other groups of animals and plants, no checklist of alien terrestrial invertebrates was available in any of the European\\u000a countries until recently. Since 2002, such checklists were successively provided by Austria (Essl and Rabitsch 2002), Germany\\u000a (Geiter et al. 2002), the Czech Republic (Šefrová and Lašt? vka 2005), Scandinavia (NOBANIS 2007), the United Kingdom (Hill\\u000a et al. 2005), Switzerland

Alain Roques; Wolfgang Rabitsch; Jean-Yves Rasplus; Carlos Lopez-Vaamonde; Wolfgang Nentwig; Marc Kenis

191

Brane Stabilization and Regionality of Extra Dimensions  

E-print Network

Extra dimensions are a common feature of beyond the Standard Model physics. In a braneworld scenario, local physics on the brane can depend strongly on the brane's location within the bulk. Generically, the relevant properties of the bulk manifold for the physics on/of the brane are neither local nor global, but depend on the structure of finite regions of the bulk, even for locally homogeneous and isotropic bulk geometries. In a recent work, various mechanisms (in a braneworld context) were considered to stabilize the location of a brane within bulk spaces of non-trivial topology. In this work we elaborate on and generalize that work by considering additional bulk and brane dimensionalities as well as different boundary conditions on the bulk scalar field that provides a Casimir force on the brane, providing further insight on this effect. In D=2+1 (D=5+1) we consider both local and global contributions to the effective potential of a 1-brane (4-brane) wrapped around both the 2-dimensional hyperbolic horn and Euclidean cone, which are used as toy models of an extra-dimensional manifold. We calculate the total energy due to brane tension and elastic energy (extrinsic curvature) as well as that due to the Casimir energy of a bulk scalar satisfying both Dirchlet and Neumann boundary conditions on the brane. In some cases stable minima of the potential are found that result from the competition of at least two of the contributions. Generically, any one of these effects may be sufficient when the bulk space has less symmetry than the manifolds considered here. We highlight the importance of the Casimir effect for the purpose of brane stabilization.

David M. Jacobs; Glenn D. Starkman; Andrew J. Tolley

2012-10-09

192

Testing extra dimensions with boundaries using Newton's law modifications  

E-print Network

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

V. K. Oikonomou; K. Kleidis

2011-01-16

193

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

PubMed

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

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

194

Astronomers Report Discovery of New Extra-solar Planets: Four Reports  

NSDL National Science Digital Library

If you are feeling alone in the universe, this news from 2000 of the search for new planets might inspire you. This account is from the popular space science Website, Space.com. It chronicles the latest detection of at least nine possible planetary bodies orbiting stars outside of our solar system. The text includes a discussion of how detection of wobble behavior is used in the search for extra-solar planets and plans for future planet hunts. This site also features links to Websites of the observatories involved in extra-solar planet detection, related Space.com stories, a diagram of Doppler shift due to stellar wobble and a table of the nine planet candidates's size and distance from Earth.

Weinstock, Maia.

2000-01-01

195

Elliptical instability in terrestrial planets and moons  

NASA Astrophysics Data System (ADS)

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

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

2012-03-01

196

Moon and Terrestrial Planets: Unresolved Questions  

NASA Astrophysics Data System (ADS)

Human exploration during Apollo began the documentation of the evolution of the Moon and of its importance in understanding the origin and evolution of the terrestrial planets. This revolution in planetary geology continues as a vigorous and vibrant arena for discovery and debate for new generations of geoscientists. Although much has been learned and, indeed, resolved in lunar science, we are left with major questions unresolved. One fundamental question is that of the origin of the Moon. A large consensus has developed in the planetary science community that the Moon was created by the "giant impact" of a Mars-sized asteroid on the Earth after the accretion of the Earth was largely complete and differentiation had begun. A minority, however, questions this consensus hypothesis because of increasing indications that the lower mantle of the Moon may be largely undifferentiated. If the issue of the high angular momentum of the Earth-Moon system can be resolved through new modeling studies, then capture of a co-orbiting planetesimal may be an important alternative to a "giant impact". Another important question, particularly in consideration of the terrestrial and Martian surface environments during the first 0.8 billion years of Earth history, is the impact record of that period as recorded on the Moon. Again, a large consensus has developed that the 50 or so large and very large impact basins identified on the Moon were created over a very short "cataclysm" between about 3.9 and 3.8 billion years ago. Here also, a minority suggests that this period of large basin formation, although distinct in lunar history, took place over several hundred million years and that the apparent cataclysm is an artifact of sampling the effects of the last few basin-forming impacts. Either way, a previously unavailable source of impactors appeared somewhere in the solar system and greatly affected terrestrial environments at the time the precursors to life were appearing on Earth. 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.

Schmitt, H. H.

2002-12-01

197

DEPARTMENT OF PHYSICS AND ASTRONOMY Extra-solar planets  

E-print Network

Burleigh Spitzer 4.5micron image GJ3483 (LTT3059 / WD0806-661) I am the white dwarf I maybe a planet... 130DEPARTMENT OF PHYSICS AND ASTRONOMY Extra-solar planets iscience seminar Dr. Matt Burleigh #12;Dr. Matt Burleigh A brief history of extra-solar planets · In the 16th century the Italian philosopher

Burleigh, Matt

198

Repeatability of extra-pair mating in tree swallows.  

PubMed

Models of sexual selection assume that female mating preferences are heritable and, thus, repeatable for individual females across multiple mating episodes. Previous studies of the repeatability of female preference have examined individuals in captivity and focused presumably on social mate choice. However, extra-pair mating is widespread and can also influence sexual selection. We examined the repeatability of extra-pair mating in a wild population of tree swallows (Tachycineta bicolor) by experimentally inducing females to lay two clutches in rapid succession within the same season. We found that the proportion of extra-pair young and the number of extra-pair sires were highly repeatable for individual females. However, the repeatability of specific extra-pair sires was low. We suggest that this unusual pattern of mating may be due to females maximizing the heterozygosity of their offspring. PMID:16499706

Whittingham, Linda A; Dunn, Peter O; Stapleton, Mary K

2006-03-01

199

The distal forelimb musculature in aquatic and terrestrial turtles: phylogeny or environmental constraints?  

PubMed Central

We compared the muscular anatomy of the distal front limb in terrestrial and aquatic chelonians to test whether observed differences between the two groups are associated with their divergent lifestyles and locomotor modes. Given the different use of the forelimb in the two environments (body support and propulsion on land vs. mainly propulsion in water) we expected that: (1) aquatic and terrestrial turtles would show differences in their muscular anatomy, with aquatic species having more individualized muscle bundles to allow for the complex forearm movements observed during swimming, and (2) that terrestrial turtles would have more robust muscles to support their body weight against gravity. To address these questions, we examined the forelimb myology and associated tissues in six aquatic or semi-aquatic turtles (Phyrnops hilarii, Podocnemis unifilis, Trachemys scripta, Sacalia bealei, Cuora amboinensis and Mauremys caspica) and six terrestrial or semi-terrestrial turtles (Geochelone chilensis, Testudo graeca, Cuora galbinifrons, Glyptemys insculpta, Terrapene carolina and Rhinoclemmys pulcherrima). This paper describes the general structure of the forelimb musculature in all species, and quantifies muscle masses in those species with more than five specimens available (Ph. hilarii, Po. unifilis and Ge. chilensis). The general structure of the forelimb muscles in the strictly terrestrial species Ge. chilensis and Tes. graeca was found to be notably different from the pattern of the aquatic and semi-aquatic species examined, showing a distinct fusion of the different muscular bodies. Ter. carolina also show a distinctly terrestrial pattern, but a less extensive tendon development. R. pulcherrima and Gl. insculpta were found to be morphologically intermediate; in the geoemydids the strictly terrestrial bauplan never appears. Quantitative differences in the robustness or mass of the distal forelimb muscles were also observed for the species investigated, supporting our prediction that the extensor muscles are more robust in terrestrial turtles. However, in contrast to our expectations, not only the extensor muscles of the distal forelimb (which are crucial in providing both body support and propulsion), but all muscles acting around the wrist were found to be heavier in terrestrial turtles. PMID:19172731

Abdala, Virginia; Manzano, Adriana S; Herrel, Anthony

2008-01-01

200

Higgs production in a warped extra dimension  

NASA Astrophysics Data System (ADS)

Measurements of the Higgs-boson production cross section at the LHC are an important tool for studying electroweak symmetry breaking at the quantum level, since the main production mechanism gg ? h is loop-suppressed in the Standard Model (SM). Higgs production in extra-dimensional extensions of the SM is sensitive to the Kaluza-Klein (KK) excitations of the quarks, which can be exchanged as virtual particles in the loop. In the context of the minimal Randall-Sundrum (RS) model with bulk fields and a brane-localized Higgs sector, we derive closed analytical expressions for the gluon-gluon fusion process, finding that the effect of the infinite tower of virtual KK states can be described in terms of a simple function of the fundamental (5D) Yukawa matrices. Given a specific RS model, this will allow one to easily constrain the parameter space, once a Higgs signal has been established. We explain that discrepancies between existing calculations of Higgs production in RS models are related to the non-commutativity of two limits: taking the number of KK states to infinity and removing the regulator on the Higgs-boson profile, which is required in an intermediate step to make the relevant overlap integrals well defined. Even though the one-loop gg ? h amplitude is finite in RS scenarios with a brane-localized Higgs sector, it is important to introduce a consistent ultraviolet regulator in order to obtain the correct result.

Carena, Marcela; Casagrande, Sandro; Goertz, Florian; Haisch, Ulrich; Neubert, Matthias

2012-08-01

201

MODIS-Derived Terrestrial Primary Production  

Microsoft Academic Search

\\u000a Temporal and spatial changes in terrestrial biological productivity have a large impact on humankind because terrestrial ecosystems\\u000a not only create environments suitable for human habitation, but also provide materials essential for survival, such as food,\\u000a fiber and fuel. A recent study estimated that consumption of terrestrial net primary production (NPP; a list of all the acronyms\\u000a is available in the

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

202

Components of mucus of terrestrial slugs (Gastropoda).  

PubMed

Mucous secretion by the body wall of the terrestrial slugs (Ariolimax columbianus, Arionidae; and other species) was found to involve at least three distinct stages--release of vesicles, formation of granules, and organization of strands. Mucus is stored intracellularly in membrane-bound vesicles, and these are shed intact from the mucous cells. Disruption of the vesicle membrane, with release of contents, can be effected by endogenous lytic agent(s), as well as by exogenous surfactants, lipid solvents, or hypotonic media. Thereupon 1-micron granules are released. These may be stable, or they may change to material that is finely granular or in the form of strands; the transition to strands is facilitated by shear stress exerted through the fluid containing the mucous components. Lectins organize, or are organized with, the strands, as evidenced by agglutination of erythrocytes on them. Mucous formation, as seen in the living slug, differs markedly from the one-step process of exocytosis of fluid mucus inferred from studies of mucous membranes fixed for ultrastructural investigation. PMID:6614215

Deyrup-Olsen, I; Luchtel, D L; Martin, A W

1983-09-01

203

Dietary characterization of terrestrial mammals  

PubMed Central

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

Pineda-Munoz, Silvia; Alroy, John

2014-01-01

204

The Laboratory for Terrestrial Physics  

NASA Technical Reports Server (NTRS)

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.

2003-01-01

205

Dietary characterization of terrestrial mammals.  

PubMed

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

Pineda-Munoz, Silvia; Alroy, John

2014-08-22

206

Evidence for Terrestrial Planetary System Remnants at White Dwarfs  

NASA Astrophysics Data System (ADS)

The last several years has brought about a dynamic shift in the view of exoplanetary systems in the post-main sequence, perhaps epitomized by the evidence for surviving rocky planetary bodies at white dwarfs. Coinciding with the launch of the Spitzer Space Telescope, both space- and ground-based data have supported a picture whereby asteroid analogs persist at a significant fraction of cool white dwarfs, and are prone to tidal disruption when passing close to the compact stellar remnant. The ensuing debris can produce a detectable infrared excess, and the material gradually falls onto the star, polluting the atmosphere with heavy elements that can be used to determine the bulk composition of the destroyed planetary body. Based on the observations to date, the parent bodies inferred at white dwarfs are best described as asteroids, and have a distinctly rocky composition similar to material found in the inner Solar System. Their minimum masses are typical of large asteroids, and can approach or exceed the mass of Vesta and Ceres, the two largest asteroids in the Solar System. From the number of stars surveyed in various studies, the fraction of white dwarfs that host terrestrial planetary system remnants is at least a few percent, but likely to be in the range 20-30%. Therefore, A- and F-type stars form terrestrial planets efficiently, with a frequency at least as high as the remnants detected at their white dwarf descendants.

Farihi, Jay

2011-03-01

207

Girls and war: an extra vulnerability.  

PubMed

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

Black, M

1998-01-01

208

Lorentz Violation in Warped Extra Dimensions  

SciTech Connect

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

Rizzo, Thomas G.; /SLAC

2011-08-11

209

Pathology of extra-nodal non Hodgkin lymphomas.  

PubMed

In the management of extra-nodal lymphomas it is important to determine whether the tumour has disseminated and whether lymph nodes are involved. Some extra-nodal lymphomas may be the result of random spread of nodal lymphoma. Specific homing, however, determines the site of many extra-nodal lymphomas, as exemplified by cutaneous T-cell lymphomas, which seem to be derived from skin-homing T-cells and mucosa-associated lymphoid tissue lymphomas that show features of the mucosal immune system. Enteropathy-associated T-cell lymphoma is derived from mucosal T-cells in patients with coeliac disease. Immunological sanctuary accounts for the localisation of primary brain, eye and testicular lymphoma. Mantle cell lymphoma frequently causes tumours in the gastrointestinal tract. Random biopsies have shown that a high proportion of patients with this lymphoma have extensive occult involvement of the gastrointestinal tract at the time of first diagnosis. Follicular lymphoma occurs at both nodal and extra-nodal sites, but uncommonly at both sites at the same time. Extra-nodal follicular lymphomas frequently lack t(14;18)(q32;q21) and do not express bcl-2, which are characteristics of the nodal disease. At extra-nodal sites, follicular lymphoma is more likely to be curable than nodal follicular lymphoma. The behaviour of extra-nodal lymphomas cannot be assumed to follow that of their nodal counterparts. PMID:22480571

Wright, D H

2012-06-01

210

Widespread Wolbachia infection in terrestrial isopods and other crustaceans 123 Widespread Wolbachia infection in terrestrial isopods  

E-print Network

Widespread Wolbachia infection in terrestrial isopods and other crustaceans 123 Widespread Wolbachia infection in terrestrial isopods and other crustaceans Richard Cordaux1 , Samuel Pichon1,3 , Houda Wolbachia infection in terrestrial isopods and other crustaceans. In: Strus J, Taiti S, Sfenthourakis S (Eds

Richard, Cordaux,

211

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

Microsoft Academic Search

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

Damjana Drobne

1997-01-01

212

Lunar and Terrestrial Planet Formation in the Grand Tack Scenario  

E-print Network

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) ...

Jacobson, Seth A

2014-01-01

213

Peatland geoengineering: an alternative approach to terrestrial carbon sequestration.  

PubMed

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

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

2012-09-13

214

Collisional Evolution of Terrestrial Planets  

NASA Astrophysics Data System (ADS)

The currently accepted model for the formation of terrestrial planets describes their growth as the collisional accumulation of rocky or sometimes molten planetesimals. The characteristics of the planets produced by this process are, to a large degree, determined by their collisional evolution, and their associated differentiation and thermal evolution. Studies of planet formation and planetary collisional evolution have typically been conducted separately. Most works of late-stage planet formation use perfectly inelastic mergers to model collisions (e.g. Agnor, Canup & Levison 1999, Chambers 2001, Levison & Agnor 2003), with certain recognized inadequacies, notably rotationally unstable spin rates acquired as a planet grows. Do planets really accrete in this manner? On the other hand, most of the work studying the collisional evolution of terrestrial planets has focused on determining the efficacy of single impacts to account for particular planetary characteristics and the formation of satellites (e.g. Benz et al. 1988, Canup & Asphaug 2001). It has been recognized for some time (Wetherill 1985) that the final characteristics (e.g. spin state, bulk composition, isotopic age) of an accreting planet are determined not by the last or single largest collision (Agnor, Canup & Levison 1999) but by all of the major collisional encounters in a planet's history. As demonstrated in our impact models, each major impact changes the silicate to metal ratio, the thermal state, and the spin state, and sets the stage for subsequent collisions. We have commenced a detailed study of collision dynamics and outcomes common to the late stage of terrestrial planet accretion. We are modeling collisions using smooth particle hydrodynamics to examine, primarily, the regimes of impact that truly allow for accretion (i.e. mass accumulation instead of mass loss). We are also studying the cumulative affect of giant impacts on major planetary characteristics (such as composition and spin) and the extent to which collisional processes may account for planetary heterogeneity. One initial outcome of this study, to be presented, is whether, and under which circumstances, the use of perfectly inelastic collisions in late stage accretion studies is appropriate.

Agnor, C. B.; Asphaug, E. I.

2003-05-01

215

Updated limits on extra dimensions through torsion and LHC data  

NASA Astrophysics Data System (ADS)

It is well known that the inclusion of torsion in the gravitational formalism, leads to four-fermion interactions. Although the coupling constant of this interaction is strongly suppressed in four dimensions, its value is enhanced in models with n extra dimensions. In this context, we reinterpret the recent limits established by LHC experiments to four-fermion contact interactions, to set bounds on the size of the extra dimensions. For n = 2, the limits are comparable to those in the literature, while for n ? 3, the volume of the extra dimensions is strongly constrained.

Castillo-Felisola, Oscar; Corral, Cristobal; Schmidt, Iván; Zerwekh, Alfonso R.

2014-05-01

216

Search for large extra dimensions in dielectron and diphoton production.  

PubMed

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

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

2001-02-12

217

Wrapped Branes and Compact Extra Dimensions in Cosmology  

E-print Network

We present a cosmological model in 1+m+p dimensions, where in m-dimensional space there are uniformly distributed p-branes wrapping over the extra p-dimensions. We find that during cosmological evolution m-dimensional space expands with the exact power-law corresponding to pressureless matter while the extra p-dimensions contract. Adding matter, we also obtain solutions having the same property. We show that this might explain in a natural way why the extra dimensions are small compared to the observed three spatial directions.

Ali Kaya; Tonguc Rador

2003-01-07

218

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

NASA Astrophysics Data System (ADS)

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 the remaining planets would be located in the Habitable Zone, suggesting that planetary systems with close-in giant planets are viable targets for searches for Earth-like habitable planets around other stars. I then present more realistic dynamical simulations of the effects of a migrating giant planet on a disk of protoplanetary material embedded in a gaseous disk, and the subsequent post-scattering evolution of the planetary system. I numerically investigate the dynamics of several types of post-migration planetary systems over 200 million years: a model with a single migrating giant planet, a model with one migrating and one nonmigrating giant planet, and a model excluding the effects of the gas disk. Material that is shepherded in front of the migrating giant planet by moving mean motion resonances accretes into "hot Earths", but survival of these bodies is strongly dependent on dynamical damping. Furthermore, a significant amount of material scattered outward by the giant planet survives in highly excited orbits; the orbits of these scattered bodies are then damped by gas drag and dynamical friction over the remaining accretion time. In all simulations Earth-mass planets accrete on approximately 100 Myr timescales, often with orbits in the Habitable Zone. These planets range in mass and water content, with both quantities increasing with the presence of a gas disk and decreasing with the presence of an outer giant planet. I use scaling arguments and previous results to derive a simple recipe that constrains which giant planet systems are able to form and harbor Earth-like planets in the Habitable Zone, demonstrating that roughly one third of the known planetary systems are potentially habitable. Finally, I present results from a search for new molecular tracers of warm gas in circumstellar disks using the NIRSPEC instrument on the Keck II telescope. I have detected emission from multiple ro-vibrational transitions in the v = 1--0 band of hydroxyl (OH) located in the inner circumstellar regions of two Herbig Ae stars, AB Aurigae and MWC 7

Mandell, Avram M.

219

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

ERIC Educational Resources Information Center

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…

Sekiguchi, Tatsuhiko; Furudate, Hiroyuki; Kimura, Tetsuya

2010-01-01

220

A New Iridovirus of Two Species of Terrestrial Isopods, Armadillidium vulgare and Porcellioscaber  

Microsoft Academic Search

Summary A new iridovirus, herein named isopod iridescent virus (IIV), was isolated from two species of terrestrial isopods in Berkeley, Calif. Infected individuals of Armadillidium vulgare and Porcellio scaber (Crustacea:Isopoda) appeared purple in color; in thin sections, hemocytes, nerve cells, and fat body cells contained cytoplasmic aggregations of virions. Isolated particles, 135 nm in diameter in negative stain, contained DNA

Anabel Cole; Jack Morris

1980-01-01

221

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

ERIC Educational Resources Information Center

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)

Wild, John F.

1973-01-01

222

Chromium stress induced alterations in biochemical and enzyme metabolism in aquatic and terrestrial plants  

Microsoft Academic Search

Water is seriously polluted by the discharge of various industrial wastewater containing heavy metals. Among them, chromium is considered to be toxic to living organisms and it is released mostly from tanneries. The chromium-contaminated water is discharged into nearby water bodies and it affects both aquatic and terrestrial plants. So the present experiment was conducted with an aquatic plant, water

K. Sankar Ganesh; L. Baskaran; S. Rajasekaran; K. Sumathi; A. L. A. Chidambaram; P. Sundaramoorthy

2008-01-01

223

Terrestrial versus giant planet formation  

NASA Technical Reports Server (NTRS)

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

Boss, Alan P.

1988-01-01

224

Methane production in terrestrial arthropods.  

PubMed Central

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

Hackstein, J H; Stumm, C K

1994-01-01

225

Line following terrestrial insect biobots.  

PubMed

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

Latif, Tahmid; Bozkurt, Alper

2012-01-01

226

Phytopharmacological overview of Tribulus terrestris  

PubMed Central

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

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

2014-01-01

227

Aerospace Power Technology for Potential Terrestrial Applications  

NASA Technical Reports Server (NTRS)

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.

Lyons, Valerie J.

2012-01-01

228

Does terrestrial epidemiology apply to marine systems?  

Microsoft Academic Search

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 trans- ferred 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

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

2004-01-01

229

Energetic Strategies of Terrestrial Vertebrates  

NSDL National Science Digital Library

This laboratory exercise investigates the difference in metabolic response of representative endotherms (mice) and ectotherms (green anoles) to temperature changes and ecological consequences are studied through behavior and preferred body temperature in a temperature gradient.

Kathy Winnett-Murray (Hope College;); K. Greg Murray (Hope College;); Lori Hertel (Hope College;); Christopher C. Barney (Hope College;)

2000-01-01

230

Solar Terrestrial Relations Observatory (STEREO)  

NASA Technical Reports Server (NTRS)

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

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

2003-01-01

231

Effects of pentachlorophenol on survival of earthworms (Lumbricus terrestris) and phagocytosis by their immunoactive coelomocytes  

Microsoft Academic Search

Earthworms, Lumbricus terrestris, exposed for 96 h to filter paper saturated with five nominal concentrations of pentachlorophenol, exhibited a 50% lethal concentration (LC50) of 25.0 μg PCP\\/cm² and corresponding whole worm body burden-based 50% lethal dose (LD50) of 877.7 μg PCP\\/g dry mass. Linear regression modeling showed that worms increased body concentrations (BC = μg PCP\\/g dry tissue mass) with

Marina A. Giggleman; Lloyd C. Fitzpatrick; Arthur J. Goven; Barney J. Venables

1998-01-01

232

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

PubMed

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

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

2013-01-01

233

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

PubMed Central

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

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

2013-01-01

234

Insignificant solar-terrestrial triggering of earthquakes  

USGS Publications Warehouse

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 ?2 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.

Love, Jeffrey J.; Thomas, Jeremy N.

2013-01-01

235

Various approaches for vegetation filtering of terrestrial laser scans  

NASA Astrophysics Data System (ADS)

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

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

2012-04-01

236

Probing Large Extra Dimensions With IceCube  

E-print Network

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.

Esmaili, Arman; Tabrizi, Zahra

2014-01-01

237

TASI 2004 Lectures on the Phenomenology of Extra Dimensions  

E-print Network

The phenomenology of large, warped, and universal extra dimensions is reviewed. Characteristic signals are emphasized rather than an extensive survey. This is the writeup of lectures given at the Theoretical Advanced Study Institute in 2004.

Graham D. Kribs

2006-05-30

238

29 CFR 541.604 - Minimum guarantee plus extras.  

...DEPARTMENT OF LABOR REGULATIONS DEFINING AND DELIMITING THE EXEMPTIONS FOR EXECUTIVE, ADMINISTRATIVE, PROFESSIONAL, COMPUTER AND OUTSIDE SALES EMPLOYEES Salary Requirements § 541.604 Minimum guarantee plus extras. (a) An...

2014-07-01

239

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

240

Physical Mechanisms of Extra Area Effects from Weather Modification.  

National Technical Information Service (NTIS)

The physical mechanisms which could have produced extra area effects downwind of the Climax I and II wintertime orographic cloud seeding experiments were investigated. The two most probable mechanisms identified, namely, artificial nuclei transport and ic...

G. J. Mulvey

1977-01-01

241

Adrenal and extra-adrenal myelolipomas - a comparative case report.  

PubMed

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

Hakim, Arsany; Rozeik, Christoph

2014-01-01

242

Adrenal and Extra-adrenal Myelolipomas - A Comparative Case Report  

PubMed Central

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

Hakim, Arsany; Rozeik, Christoph

2014-01-01

243

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

NASA Technical Reports Server (NTRS)

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.

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

1988-01-01

244

Niche Habitats for ExtraTerrestrial Life: The Potential for Astrobiology on the Moons of Saturn and Jupiter  

Microsoft Academic Search

Astrobiology today has a strong anticipatory focus, and efforts are concentrated on determining the factors behind the potential presence, type, and distribution of life in our solar system and beyond. The critical requirements for life: a liquid solvent, and electron acceptors and donors for metabolism, guide the search, and is a central concept to the location and extent of circumstellar

Leila Battison

2011-01-01

245

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

NASA Astrophysics Data System (ADS)

In the talk, a new approach to the analysis of spatial-angular characteristics of cosmic ray muon flux variations detected by muon hodoscope is considered. Various parameters of local angular anisotropy and the technique of their evaluation are discussed. It is shown that the most sensitive parameter to different disturbances in the Heliosphere (and the Magnetosphere) is the projection of the vector of relative anisotropy of muon flux on the horizontal plane. This value characterizes the lateral shift of the angular distribution of muon flux. Some examples of the application of this parameter for description of muon flux changes during various heliospheric processes are considered.

Barbashina, Natalia; Astapov, Ivan; Petrukhin, Anatoly; Yashin, Igor; Yakovleva, Elena; Kokoulin, Rostislav; Shutenko, Victor; Dmitrieva, Anna

246

New Developments in Extra-dimensional Dark Matter  

E-print Network

We summarize the main features of several dark matter candidates in extra-dimensional theories. In particular, we review Kaluza-Klein (KK) gravitons in universal extra dimensions and branons in brane-world models. KK gravitons are superWIMP (superweakly-interacting massive particle) dark matter, and branons are WIMP (weakly-interacting massive particle) dark matter. Both dark matter candidates are naturally produced in the correct amount to form much or all of dark matter.

Jose A. R. Cembranos; Antonio Dobado; Jonathan L. Feng; Antonio L. Maroto; Arvind Rajaraman; Fumihiro Takayama

2005-12-22

247

Low Scale Unification, Newton's Law and Extra Dimensions  

E-print Network

Motivated by recent work on low energy unification, in this short note we derive corrections on Newton's inverse square law due to the existence of extra decompactified dimensions. In the four-dimensional macroscopic limit we find that the corrections are of Yukawa type. Inside the compactified space of n-extra dimensions the sub-leading term is proportional to the (n+1)- power of the distance over the compactification radius ratio. Some physical implications of these modifications are briefly discussed.

E. G. Floratos; G. K. Leontaris

1999-06-03

248

Low scale unification, Newton's law and extra dimensions  

Microsoft Academic Search

Motivated by recent work on low energy unification, in this short note we derive corrections on Newton's inverse square law due to the existence of extra decompactified dimensions. In the four-dimensional macroscopic limit we find that the corrections are of Yukawa type. Inside the compactified space of n-extra dimensions the sub-leading term is proportional to the (n+1)-power of the distance

Emmanuel G Floratos; George K Leontaris

1999-01-01

249

Extra EPR Spectra of Iron-Doped Rutile  

Microsoft Academic Search

We have discovered that besides the well-known EPR spectrum of Fe3+ substitutional ions in iron-doped rutile there are several other EPR spectra related to Fe3+ ions. The interpretation of these extra spectra was made considering the intensity variation with heat treatment and the orientation of the magnetic axes of the extra spectra. Isofrequency diagrams were recorded at 9.2 GHz and

Per-Olof Andersson; Erik L. Kollberg; Andrzej Jelenski

1973-01-01

250

Multiple extra macular branch retinal vein occlusions in hyperhomocysteinemia  

PubMed Central

Hyperhomocysteinemia is a well-known modifiable risk factor for thromboembolism. Retinal vascular occlusion in patients having hyperhomocysteinemia is a known entity, particularly in young patients. However, multiple extra macular branch retinal vein occlusion (BRVO) is a rare condition, which can be a presentation of this disease. We present a patient who had multiple extra macular BRVO; on complete systemic workup, he was found to have raised homocysteine levels. PMID:24817751

Gore, Abhijit Diwakar; Rao, Girish Shiva; Gore, Mansi Abhijit; Desai, Abhishek R

2014-01-01

251

Radiologic-pathologic correlation in extra-adrenal myelolipoma.  

PubMed

Myelolipoma is an uncommon benign tumor that classically arises in the adrenal glands. Most cases are asymptomatic, with incidental detection of this tumor on cross-sectional imaging performed for other causes. Extra-adrenal occurrence of myelolipoma has been infrequently reported, with scarce radiology literature on the topic. We present radiologic and pathologic correlation in two cases of image-guided biopsy proven extra-adrenal myelolipoma in the presacral and paraaortic location, with review of literature. PMID:24370965

Itani, Malak; Wasnik, Ashish P; Platt, Joel F

2014-04-01

252

Extra-Pair Mating and Evolution of Cooperative Neighbourhoods  

PubMed Central

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

Eliassen, Sigrunn; J?rgensen, Christian

2014-01-01

253

Scaling of the hydrostatic skeleton in the earthworm Lumbricus terrestris.  

PubMed

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

Kurth, Jessica A; Kier, William M

2014-06-01

254

Background exposure rates of terrestrial wildlife in England and Wales.  

PubMed

It has been suggested that, when assessing radiation impacts on non-human biota, estimated dose rates due to anthropogenically released radionuclides should be put in context by comparison to dose rates from natural background radiation. In order to make these comparisons, we need data on the activity concentrations of naturally occurring radionuclides in environmental media and organisms of interest. This paper presents the results of a study to determine the exposure of terrestrial organisms in England and Wales to naturally occurring radionuclides, specifically (40)K, (238)U series and (232)Th series radionuclides. Whole-body activity concentrations for the reference animals and plants (RAPs) as proposed by the ICRP have been collated from literature review, data archives and a targeted sampling campaign. Data specifically for the proposed RAP are sparse. Soil activity concentrations have been derived from an extensive geochemical survey of the UK. Unweighted and weighted absorbed dose rates were estimated using the ERICA Tool. Mean total weighted whole-body absorbed dose rates estimated for the selected terrestrial organisms was in the range 6.9 x 10(-2) to 6.1 x 10(-1) microGy h(-1). PMID:18440107

Beresford, N A; Barnett, C L; Jones, D G; Wood, M D; Appleton, J D; Breward, N; Copplestone, D

2008-09-01

255

Long-term solar-terrestrial observations  

NASA Astrophysics Data System (ADS)

In the fall of 1985, the Committee on Solar-Terrestrial Research (CSTR) created a panel to study the requirements for long-term monitoring and archiving of solar-terrestrial data. The panel comprised specialists in all four areas that constitute solar-terrestrial science: the sun, interplanetary medium, magnetosphere-thermosphere-ionosphere, and upper atmosphere. It interviewed many individuals from the solar-terrestrial monitoring and data archiving communities, along with administrators and directors from appropriate government agencies. It circulated nearly 500 questionnaires to obtain information and opinions from the broader community to learn which observational data should be considered essential over the long term to support the operational and research needs of solar-terrestrial science. This report summarizes the panel's principal findings, and the panel's recommendations follow. A separate section listing the critical observational needs by area is presented together with the scientific rationale for each area. The recommendations are defended in terms of this explicit scientific rationale and the multifold uses of current and long-term solar-terrestrial observations for continued operational solar-terrestrial forecasts and services.

256

Radiological outcomes of distal radius extra-articular fragility fractures treated with extra-focal kirschner wires  

Microsoft Academic Search

IntroductionThe classical colles fracture (extra-articular, dorsally angulated distal radius fracture) in patients with osteoporotic bone is becoming increasingly more frequent. There still appears to be no clear consensus on the most appropriate surgical management of these injuries. The purpose of this study is to appraise the use of percutaneous extra-focal pinning, in the management of the classical colles fracture.

C. Kennedy; M. T. Kennedy; D. Niall; A. Devitt

2010-01-01

257

The role of Clouds in Emitted, Reflected and Transmitted Spectra of Terrestrial Exoplanets  

NASA Astrophysics Data System (ADS)

Two objectives of the NASA-Terrestrial Planet Finder and ESA-Darwin missions are to characterize the environments of terrestrial planets outside of our solar system and to search for life on these planets. These objectives will be met by measuring the disk-averaged spectra of the radiation reflected or emitted from these planets. Clouds play a significant role in determining these spectra. For Earth, water clouds can reduce the infrared emission by up to 50 and increase the visible reflectance by up to 400%. The disk-averaged spectra of a cloudy planet are also very sensitive to the observed planetary phase. For Earth, we see up to 40% increases of the solar albedo from the gibbous phase to the fully illuminated phase. Moreover, clouds strongly modify the strength of absorption features due to tropospheric trace gases and may impact the detectability of surface biosignatures in the visible (Tinetti et al.,2005). Stellar occultation might provide another effective method for probing the atmospheres of Earth-size extrasolar planets in the not too distant future. In the transmission spectra of terrestrial planets in transit, clouds act, to a first order approximation, as an optically thick layer at a given altitude. A uniform cloud layer will effectively increase the apparent radius of the planet and yield information only about atmospheric components existing above the clouds. The altitude where the cloud deck occurs, changes for Venus-like, Earth-like or highly-condensable-volatile rich planets (Ehrenreich et al.,2005). The radiative properties of clouds are strongly dependent on the chemical species that condense or freeze (e.g. water for present-day Earth, methane for Titan etc.), the particle size distributions present and particle shapes. Therefore, an understanding of aerosol and cloud microphysics on extra-solar terrestrial planets is necessary to properly interpret the spectra of terrestrial planets, emitted, reflected or transmitted. This work was supported by NASA-Astrobiology Institute/Caltech/CNRS.

Tinetti, G.; Yung, Y. L.; Ehrenreich, D.; Meadows, V. S.; Crisp, D.; Kahn, B.; Lecavelier des Etangs, A.; Vidal-Madjar, A.

2005-12-01

258

Solar Terrestrial Physics: Present and Future  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

259

Terrestrial Mobile Mapping: photogrammetric simulator  

NASA Astrophysics Data System (ADS)

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

Taglioretti, C.; Manzino, A. M.

2014-08-01

260

Terrestrial cooling and solar variability  

NASA Technical Reports Server (NTRS)

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.

Agee, E. M.

1982-01-01

261

Terrestrial Planet Finder: science overview  

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

262

Bibliography of terrestrial impact structures  

NASA Technical Reports Server (NTRS)

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.

Grolier, M. J.

1985-01-01

263

Steroidal saponins from Tribulus terrestris.  

PubMed

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-?-d-glucopyranosyl-(25R)-furost-4-en-2?,3?,22?,26-tetrol-12-one (terrestrinin C), 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-22?,26-diol-3,12-dione (terrestrinin D), 26-O-?-d-glucopyranosyl-(25S)-furost-4-en-22?,26-diol-3,6,12-trione (terrestrinin E), 26-O-?-d-glucopyranosyl-(25R)-5?-furostan-3?,22?,26-triol-12-one (terrestrinin F), 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-12?,22?,26-triol-3-one (terrestrinin G), 26-O-?-d-glucopyranosyl-(1?6)-?-d-glucopyranosyl-(25R)-furost-4-en-22?,26-diol-3,12-dione (terrestrinin H), and 24-O-?-d-glucopyranosyl-(25S)-5?-spirostan-3?,24?-diol-12-one-3-O-?-d-glucopyranosyl-(1?4)-?-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. PMID:25172515

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

264

Terrestrial Energy Storage SPS Systems  

NASA Technical Reports Server (NTRS)

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.

Brandhorst, Henry W., Jr.

1998-01-01

265

Homogeneous Dynamos and Terrestrial Magnetism  

Microsoft Academic Search

The main object of the paper is to discuss the possibility of a body of homogeneous fluid acting as a self-exciting dynamo. The discussion is for the most part confined to the solution of Maxwell's equations for a sphere of electrically conducting fluid in which there are specified velocities. Solutions are obtained by expanding the velocity and the fields in

Edward Bullard; H. Gellman

1954-01-01

266

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

PubMed Central

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

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

2009-01-01

267

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

SciTech Connect

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.

Drobne, D. [Univ. of Ljubljana (Slovenia). Dept. of Biology

1997-06-01

268

Foreign Bodies  

MedlinePLUS

... sometimes stick things in their mouths, ears, and noses. Some foreign bodies, like a small splinter, do not cause serious harm. Inhaled or swallowed foreign bodies may cause choking or bowel obstruction and may require medical care.

269

Body Measurement.  

ERIC Educational Resources Information Center

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

Neufeld, K. Allen

1989-01-01

270

The Geology of the Terrestrial Planets  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

271

AIR POLLUTION EFFECTS ON TERRESTRIAL ECOSYSTEMS  

EPA Science Inventory

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

272

Terrestrial passage theory of the moon illusion.  

PubMed

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

Reed, C F

1984-12-01

273

Transfer of terrestrial technology for lunar mining  

NASA Technical Reports Server (NTRS)

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.

Hall, Robert A.; Green, Patricia A.

1992-01-01

274

DEVELOPMENT OF SCALING CRITERIA FOR TERRESTRIAL MICROCOSMS  

EPA Science Inventory

Theoretical developments based on heat and moisture transfer in soil lead to dimensionless numbers that describe important processes taking place in a terrestrial microcosm. These numbers provide preliminary scientific criteria for scaling the results from microcosms both as a me...

275

Update on terrestrial ages of Antarctic meteorites  

NASA Astrophysics Data System (ADS)

Cosmic-ray produced Cl-36 (half-life = 3.01 x 10 to the 5th years) has been measured in 90 Antarctic meteorites by accelerator mass spectrometry. The terrestrial ages of the meteorites were calculated from the results. After excluding possible paired objects, 138 terrestrial ages from 18 different locations are available from C-14, Kr-81, and Cl-36 measurements for application to Antarctic meteorite and glaciological studies. The terrestrial ages of Allan Hills meteorites vary from 2000 years to 1 million years and are clearly longer than those of Yamato meteorites and other Antarctic meteorites. The oldest Allan Hills meteorites were found close to the eastern edge and in the southeast of the main icefield. Among all Antarctic meteorites measured to date, only L and LL chondrites have terrestrial ages older than 370,000 years.

Nishiizumi, K.; Elmore, D.; Kubik, P. W.

1989-07-01

276

Data Base of Terrestrial Impact Structures  

NSDL National Science Digital Library

Database of Terrestrial Impact Structures leads to Natural Resources Canada's interactive global database of impact structures, complete with photographs and summary information. For those interested in learning more about Impact Craters, this is a fine starting point.

1997-01-01

277

High Efficiency, Long Life Terrestrial Solar Panel.  

National Technical Information Service (NTIS)

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 evalua...

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

1977-01-01

278

Particle creation in the presence of a warped extra dimension  

SciTech Connect

Particle creation in spacetimes with a warped extra dimension is studied. In particular, we investigate the dynamics of a conformally coupled, massless scalar field in a five-dimensional warped geometry where the induced metric on the 3-branes is that of a spatially flat cosmological model. We look at situations where the scale of the extra dimension is assumed (i) to be time independent or (ii) to have specific functional forms for time dependence. The warp factor is chosen to be that of the Randall-Sundrum model. With particular choices for the functional form of the scale factor (and also the function characterizing the time evolution of the extra dimension) we obtain the |{beta}{sub k}|{sup 2}, the particle number and energy densities after solving (wherever possible, analytically but, otherwise, numerically) the conformal scalar field equations. The behaviours of these quantities for the massless and massive Kaluza-Klein modes are examined. Our results show the effect of a warped extra dimension on particle creation and illustrate how the nature of particle production on the brane depends on the nature of warping, and the type of cosmological evolution as well as the temporal evolution of the extra dimension.

Ghosh, Suman; Kar, Sayan, E-mail: suman@cts.iitkgp.ernet.in, E-mail: sayan@cts.iitkgp.ernet.in [Department of Physics and Centre for Theoretical Studies, Indian Institute of Technology, Kharagpur 721 302 (India)] [Department of Physics and Centre for Theoretical Studies, Indian Institute of Technology, Kharagpur 721 302 (India)

2008-08-15

279

Extra area effects of cloud seeding - An updated assessment  

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

280

Parallel Computing for Terrestrial Ecosystem Carbon Modeling  

SciTech Connect

Terrestrial ecosystems are a primary component of research on global environmental change. Observational and modeling research on terrestrial ecosystems at the global scale, however, has lagged behind their counterparts for oceanic and atmospheric systems, largely because the unique challenges associated with the tremendous diversity and complexity of terrestrial ecosystems. There are 8 major types of terrestrial ecosystem: tropical rain forest, savannas, deserts, temperate grassland, deciduous forest, coniferous forest, tundra, and chaparral. The carbon cycle is an important mechanism in the coupling of terrestrial ecosystems with climate through biological fluxes of CO{sub 2}. The influence of terrestrial ecosystems on atmospheric CO{sub 2} can be modeled via several means at different timescales. Important processes include plant dynamics, change in land use, as well as ecosystem biogeography. Over the past several decades, many terrestrial ecosystem models (see the 'Model developments' section) have been developed to understand the interactions between terrestrial carbon storage and CO{sub 2} concentration in the atmosphere, as well as the consequences of these interactions. Early TECMs generally adapted simple box-flow exchange models, in which photosynthetic CO{sub 2} uptake and respiratory CO{sub 2} release are simulated in an empirical manner with a small number of vegetation and soil carbon pools. Demands on kinds and amount of information required from global TECMs have grown. Recently, along with the rapid development of parallel computing, spatially explicit TECMs with detailed process based representations of carbon dynamics become attractive, because those models can readily incorporate a variety of additional ecosystem processes (such as dispersal, establishment, growth, mortality etc.) and environmental factors (such as landscape position, pest populations, disturbances, resource manipulations, etc.), and provide information to frame policy options for climate change impact analysis.

Wang, Dali [ORNL; Post, Wilfred M [ORNL; Ricciuto, Daniel M [ORNL; Berry, Michael [University of Tennessee, Knoxville (UTK)

2011-01-01

281

Body weight, diet and home range area in primates  

Microsoft Academic Search

Primates show a strong positive relationship between body weight and home range area. Dietary habits also influence home range area. Folivorous primates occupy smaller home range areas for their body weight than do frugivores and omnivores. Primates generally require smaller home range area per individual than solitary terrestrial mammals, but primates living in social groups have much larger total home

Katharine Milton; Michael L. May

1976-01-01

282

CP violation from pure gauge in extra dimensions  

NASA Astrophysics Data System (ADS)

One of the Sakharov's condition for baryogenesis is the violation of both C and CP. In the Standard Model, gauge interactions break maximally C, but CP is only broken through the Yukawa couplings in the poorly understood scalar sector. In extra-dimensional models, extra components of gauge fields behave as scalars in 4D and can acquire effective vev's through (finite) quantum effects (Hosotani mechanism). This mechanism is used to build a toy model with 2 extra-dimensions compactified on a flat torus T 2, where a SU(2) gauge symmetry is broken to U(1) and CP violation (in 4D) is expected. This is verified by computing a non-vanishing electric dipole moment.

Frère, Jean-Marie; Libanov, Maxim; Mollet, Simon

2014-06-01

283

AMS-02 and next-to-minimal universal extra dimensions  

NASA Astrophysics Data System (ADS)

The anomaly detected by AMS-02 and PAMELA in the cosmic-ray positron flux when interpreted as arising from dark matter annihilation suggests that dark matter may interact differently with hadrons and leptons so as to remain compatible with cosmic-ray antiproton data. Such a scenario is readily accommodated in models with extra spatial dimensions. We study indirect detection of Kaluza-Klein (KK) dark matter in universal extra dimensions with brane-localized terms and fermion bulk masses: next-to-minimal universal extra dimensions. So that an excess of antiprotons is not produced in explaining the positron anomaly, it is necessary that the KK bulk masses in the lepton and hadron sectors be distinct. Even so, we find that cosmic-ray data disfavor a heavy KK photon dark matter scenario. Also, we find these scenarios with flavor-universal bulk masses to be in conflict with dijet and dilepton searches at the LHC.

Gao, Yu; Kong, Kyoungchul; Marfatia, Danny

2014-05-01

284

Helical cosmological magnetic fields from extra-dimensions  

E-print Network

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 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...

Atmjeet, Kumar; Subramanian, Kandaswamy

2014-01-01

285

Fermion Generations from "Apple-Shaped" Extra Dimensions  

E-print Network

We examine the behavior of fermions in the presence of an internal compact 2-manifold which in one of the spherical angles exhibits a conical character with an obtuse angle. The extra manifold can be pictured as an apple-like surface i.e. a sphere with an extra "wedge" insert. Such a surface has conical singularities at north and south poles. It is shown that for this setup one can obtain, in four dimensions, three trapped massless fermion modes which differ from each other by having different values of angular momentum with respect to the internal 2-manifold. The extra angular momentum acts as the family label and these three massless modes are interpreted as the three generations of fundamental fermions.

Merab Gogberashvili; Pavle Midodashvili; Douglas Singleton

2007-06-05

286

Dark Energy from Casimir Energy on Noncommutative Extra Dimensions  

E-print Network

We study the possibility that dark energy is a manifestation of the Casimir energy on extra dimensions with the topology of $S^2$. We consider our universe to be $M^4 \\times S^2$ and modify the geometry by introducing noncommutativity on the extra dimensions only, i.e. replacing $S^2$ with the fuzzy version $S_{F}^2$. We find the energy density as a function of the size of the representation $M+1$ of the algebra of $S_{F}^2$, and we calculate its value for the $M+1=2$ case. The value of the energy density turns out to be positive, i.e. provides dark energy, and the size of the extra dimensions agrees with the experimental limit. We also recover the correct commutative limit as the noncommutative parameter goes to zero.

S. Fabi; B. Harms; G. Karatheodoris

2006-07-20

287

No evidence of genetic benefits from extra-pair fertilisations in female sand martins ( Riparia riparia )  

Microsoft Academic Search

Genetic parentage studies of socially monogamous birds reveal a widespread prevalence of extra-pair paternity. Variation in\\u000a extra-pair paternity among individuals may depend on how different individuals benefit from extra-pair fertilisations and\\u000a on the opportunity to pursue extra-pair copulations. A long-term study of sand martins (Riparia riparia) in Hungary allowed us to examine patterns of extra-pair fertilisations in a large colony

Jakob Augustin; Donald Blomqvist; Tibor Szép; Zoltán D. Szabó; Richard H. Wagner

2007-01-01

288

Body Weight and Body Image  

Microsoft Academic Search

HEALTH ISSUE: Body weight is of physical and psychological importance to Canadian women; it is associated with health status, physical activity, body image, and self-esteem. Although the problems associated with overweight and obesity are indeed serious, there are also problems connected to being underweight. Weight prejudice and the dieting industry intensify body image concerns for Canadian women and can have

Marion P. Olmsted; Traci McFarlane

2004-01-01

289

Observations at terrestrial impact structures: Their utility in constraining crater formation  

NASA Astrophysics Data System (ADS)

Hypervelocity impact involves the near instantaneous transfer of considerable energy from the impactor to a spatially limited near-surface volume of the target body. Local geology of the target area tends to be of secondary importance, and the net result is that impacts of similar size on a given planetary body produce similar results. This is the essence of the utility of observations at impact craters, particularly terrestrial craters, in constraining impact processes. Unfortunately, there are few well-documented results from systematic contemporaneous campaigns to characterize specific terrestrial impact structures with the full spectrum of geoscientific tools available at the time. Nevertheless, observations of the terrestrial impact record have contributed substantially to fundamental properties of impact. There is a beginning of convergence and mutual testing of observations at terrestrial impact structures and the results of modeling, in particular from recent hydrocode models. The terrestrial impact record provides few constraints on models of ejecta processes beyond a confirmation of the involvement of the local substrate in ejecta lithologies and shows that Z-models are, at best, first order approximations. Observational evidence to date suggests that the formation of interior rings is an extension of the structural uplift process that occurs at smaller complex impact structures. There are, however, major observational gaps and cases, e.g., Vredefort, where current observations and hydrocode models are apparently inconsistent. It is, perhaps, time that the impact community as a whole considers documenting the existing observational and modeling knowledge gaps that are required to be filled to make the intellectual breakthroughs equivalent to those of the 1970s and 1980s, which were fueled by observations at terrestrial impact structures. Filling these knowledge gaps would likely be centered on the later stages of formation of complex and ring structures and on ejecta.

Grieve, Richard A. F.; Therriault, Ann M.

2004-02-01

290

[Extra-periosteal mask-lift. Technical note].  

PubMed

Based on the work by Caix and Goin, it seemed logical to perform mask-lift by extra-periosteal dissection, as it is the adipose and cutaneous planes which are affected by age, while the periosteum is not distended. It is much more logical to directly displace the planes concerned by the operation rather than operating underneath the periosteum, a relatively poorly extensible barrier. Apart from the dangerous zone of the middle third of the zygoma, the frontal branch of the facial nerve is at no greater risk than during a forehead facelift. Extra-periosteal dissection does not raise any particular problems in the malomaxillary region. PMID:8304736

Trepsat, F

1993-04-01

291

FAST TRACK COMMUNICATION: A gravitational wave window on extra dimensions  

NASA Astrophysics Data System (ADS)

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.

Clarkson, Chris; Seahra, Sanjeev S.

2007-05-01

292

Bulk scalar field in warped extra dimensional models  

NASA Astrophysics Data System (ADS)

This work presents a general formalism to analyze a generic bulk scalar field in a multiple warped extra-dimensional model with arbitrary number of extra dimensions. The Kaluza-Klein mass modes along with the self-interaction couplings are determined and the possibility of having lowest lying KK mode masses near TeV scale are discussed. Also some numerical values for low-lying KK modes has been presented showing explicit localization around TeV scale. It is argued that the appearance of large number of closely spaced KK modes with enhanced coupling may prompt possible new signatures in collider physics.

Chakraborty, Sumanta; SenGupta, Soumitra

2014-06-01

293

Shape versus volume: making large flat extra dimensions invisible.  

PubMed

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

Dienes, Keith R

2002-01-01

294

Early Formation of Terrestrial Crust  

NASA Astrophysics Data System (ADS)

Early (?4.5 Ga) Formation of Terrestrial Crust T.M. Harrison1, A.K. Schmitt1, M.T. McCulloch2, and O.M. Lovera1 1Department of Earth and Space Sciences and IGPP, UCLA, Los Angeles, CA 90095, USA; 2Research School of Earth Sciences, Australian National University, Canberra, A.C.T. 2601 AUSTRALIA Large deviations in ?repsilonHf(T) from bulk silicate Earth seen in >4 Ga detrital zircons from Jack Hills, Western Australia, have been interpreted as reflecting a major differentiation of the silicate Earth at ca. 4.4 to 4.5 Ga. We have expanded the characterization of 176Hf/177Hf (Hf) in Hadean zircons by acquiring a further 116 laser ablation Lu-Hf measurements on 87 grains with ion microprobe 207Pb/206Pb ages up to 4.36 Ga. Most measurements employed concurrent Lu-Hf and 207Pb/206Pb analyses, permitting assessment of the use of ion microprobe data to characterize the age of the volumetrically larger domain sampled by laser drilling. Our new results confirm and extend the earlier observation of significant negative deviations in ?repsilonHf(T) throughout the Hadean, although no positive ?repsilonHf(T) values were documented in this study. These data yields an essentially uniform spectrum of single-stage model ages between 4.54 and 4.20 Ga for extraction of the zircons' protoliths from a chondritic reservoir. We derived the full error propagation expression for a parameter, ?repsilono, which measures the difference of a sample from solar system initial (Hf) (Hfo), and from this conclude that data plotting close to (Hfo), are statistically meaningful and consistent with silicate differentiation at 4.540±0.006 Ga. ?18O and Ti thermometry for these Hadean zircons show little obvious correlation with initial (Hf), consistent with their derivation through fusion of a broad suite of crustal rock types under near water-saturated conditions. Together with the inclusion assemblage and other isotopic and trace element data obtained from these ancient zircons, our results indicate essentially continuous derivation of crust from the mantle from 4.5 to 4.2 Ga, concurrent with recycling into the mantle and internal crustal re-working. These results represent further evidence that by 4.35 Ga, portions of the crust had taken on continental characteristics.

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

2007-12-01

295

Groundwater and Terrestrial Water Storage  

NASA Technical Reports Server (NTRS)

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

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

2011-01-01

296

Lunar and terrestrial planet formation in the Grand Tack scenario.  

PubMed

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

Jacobson, S A; Morbidelli, A

2014-09-13

297

Lunar and terrestrial planet formation in the Grand Tack scenario  

NASA Astrophysics Data System (ADS)

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.

Jacobson, S. A.; Morbidelli, A.

2014-09-01

298

MODIS-Derived Terrestrial Primary Production  

NASA Astrophysics Data System (ADS)

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

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

299

Terrestrial plasma source - a new perspective in solar-terrestrial processes from Dynamics Explorer  

Microsoft Academic Search

The geospace environment has been viewed as a mixing bowl for plasmas of both solar and terrestrial origin. The present perspective on the nature of the supply mechanisms has undergone a radical evolution over the past decade, particularly during the five years of the Dynamics Explorer mission. During this period, the terrestrial source has increased in importance in both magnitude

Charles R. Chappell

1988-01-01

300

The terrestrial plasma source - A new perspective in solar-terrestrial processes from Dynamics Explorer  

Microsoft Academic Search

The geospace environment has been viewed as a mixing bowl for plasmas of both solar and terrestrial origin. The present perspective on the nature of the supply mechanisms has undergone a radical evolution over the past decade, particularly during the five years of the Dynamics Explorer mission. During this period, the terrestrial source has increased in importance in both magnitude

Charles R. Chappell

1988-01-01

301

The terrestrial plasma source: A new perspective in solar-terrestrial processes from Dynamics Explorer  

Microsoft Academic Search

The geospace environment has been viewed as a mixing bowl for plasmas of both solar and terrestrial origin. Our perspective on the nature of the supply mechanisms has undergone a radical evolution over the past decade, particularly during the 5 years of the Dynamics Explorer mission. During this period, the terrestrial source has increased in importance in both magnitude and

Charles R. Chappell

1988-01-01

302

Body Parts  

NSDL National Science Digital Library

In this online game, learners test their knowledge of human anatomy. Learners are presented a mystery image of a body part and use their mouse to select the proper body part from a full size anatomical model (known as "Jerome"). Learners try to match all 10 body parts correctly. Use this activity to review human anatomy and/or introduce learners to the use of anatomical models.

National Museum Of American History, Smithsonian I.

2012-06-26

303

Planetary Protection: Two Relevant Terrestrial Examples  

NASA Astrophysics Data System (ADS)

Concerns about potential pathogens in returned samples from Mars ("Mars Sample Return: Issues and Recommendations", National Research Council, 1997) or planetary satellites ("Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies", National Research Council, 1998) focus on two potential types of pathogenesis, toxic and infectious. The National Research Council reports cited above state that the chances of extraterrestrial organisms proving either toxic or infectious to humans are extremely low, but cannot be entirely ruled out. Here I discuss recently discovered terrestrial examples relevant to each possibility, in order to make these concerns concrete. The first example concerns the production of hepatotoxins (toxins affecting the liver) and neurotoxins by cyanobacteria in glacial lakes on alpine pastures in Switzerland. In this example, mat-forming benthic cyanobacteria are implicated in a hundred cattle poisonings that have been reported from alpine pasteurs in southeastern Switzerland over the past twenty-five years (e.g. K. Mez et al, Hydrobiologia 368, 1-15 (1998)). It is unlikely that these cyanobacteria evolved the toxins in response to dairy cows; rather the susceptibility of cattle to these toxins seems simply to be an unfortunate coincidence of a toxin working across a large evolutionary distance. The second example concerns the recent demonstration that the decimation of shallow-water Caribbean elkhorn coral is due to infection by a common fecal enterobacterium associated with the human gut (K. L. Patterson et al., PNAS 99, 8725-8730 (2002)). The bacterium, Serratia marcenscens, is also a free-living microbe in water and soil, as well as an opportunistic pathogen in a variety of animal species. The distance between humans and corals emphasizes the possibility that certain organisms may prove pathogenic across a wide evolutionary divide. Of course, in neither of these cases are the evolutionary distances crossed as large as those that would likely exist between any martian organisms and human beings. The possibility that life on the two worlds might share a common ancestor suggests that these distances may not be altogether incomparable, but this remains speculation pending further exploration. This work is supported in part by the NASA Exobiology Program and a Presidential Early Career Award for Scientists and Engineers.

Chyba, C.

2002-09-01

304

Body Piercing  

PubMed Central

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

Koenig, Laura M; Carnes, Molly

1999-01-01

305

Supporting tools of solar-terrestrial science  

NASA Technical Reports Server (NTRS)

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.

1989-01-01

306

Terrestrial Planet Formation Around Close Binary Stars  

NASA Technical Reports Server (NTRS)

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.

Lissauer, Jack J.; Quintana, Elisa V.

2003-01-01

307

Extra-team Connections for Knowledge Transfer between Staff Teams  

ERIC Educational Resources Information Center

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…

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

2009-01-01

308

Lesson of the Heart: An Extra-Credit Assignment  

ERIC Educational Resources Information Center

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…

Lehman, Linda L.

2012-01-01

309

Position Paper on Extra-Library Information Service. Final Report.  

ERIC Educational Resources Information Center

Extra-library information services are helping libraries find solutions to the problems created by the changes in the information environment, the demand for current information, and the media by which the knowledge is distributed. There are three types of these services: (1) document handling systems, (2) data handling systems, and (3)…

Myatt, DeWitt O.; Barclay, Donald A.

310

ExtraSolar Planets Finding Extrasolar Planets. I  

E-print Network

close to the star. #12;Orbits Planets do not orbit the Sun - they both orbit the center of mass Planets. III Transits Six planets have been found by transits. This requires an edge-on orbit. JupiterExtraSolar Planets #12;Finding Extrasolar Planets. I Direct Searches Direct searches are difficult

Walter, Frederick M.

311

Sneak in Some Extra Learning by Using Instructive Feedback.  

ERIC Educational Resources Information Center

This article explains how to use instructive feedback (presenting extra information during feedback following students' responses to direct instruction) to intentionally and methodically boost students' learning. The process involves identifying information to be supplied, deciding how to present the information, using the method consistently, and…

Werts, Margaret Gessler; And Others

1996-01-01

312

INTRODUCTION TO ECMO FOR PARENTS (ECMO = "Extra Corporeal Membrane Oxygenation",  

E-print Network

, or certain heart conditions may benefit from ECMO therapy. Your child's doctor will discuss with you/or heart disease is thought to be reversible. « Back to Top What is ECMO? ECMO stands for ExtracorporealINTRODUCTION TO ECMO FOR PARENTS (ECMO = "Extra Corporeal Membrane Oxygenation", meaning heart

Kay, Mark A.

313

Testing for large extra dimensions with neutrino oscillations  

NASA Astrophysics Data System (ADS)

We consider a model where sterile neutrinos can propagate in a large compactified extra dimension giving rise to Kaluza-Klein (KK) modes and the standard model left-handed neutrinos are confined to a 4-dimensional spacetime brane. The KK modes mix with the standard neutrinos modifying their oscillation pattern. We examine former and current experiments such as CHOOZ, KamLAND, and MINOS to estimate the impact of the possible presence of such KK modes on the determination of the neutrino oscillation parameters and simultaneously obtain limits on the size of the largest extra dimension. We found that the presence of the KK modes does not essentially improve the quality of the fit compared to the case of the standard oscillation. By combining the results from CHOOZ, KamLAND, and MINOS, in the limit of a vanishing lightest neutrino mass, we obtain the stronger bound on the size of the extra dimension as ˜1.0(0.6)?m at 99% C.L. for normal (inverted) mass hierarchy. If the lightest neutrino mass turns out to be larger, 0.2 eV, for example, we obtain the bound ˜0.1?m. We also discuss the expected sensitivities on the size of the extra dimension for future experiments such as Double CHOOZ, T2K, and NO?A.

Machado, P. A. N.; Nunokawa, H.; Funchal, R. Zukanovich

2011-07-01

314

Three new extra-neotropical species of Troctopsocidae (Insecta: Psocoptera)  

Microsoft Academic Search

The family Troctopsocidae (suborder: Troctomorpha) is essentially neotropical, the only extra-neotropical species previously known is Chelyopsocus garganicus Lienhard, from southern Italy. The genus Chelyopsocus is redefined and a second European species is described from Greece: Chelyopsocus hauseri sp. nov. Nymphal glandular setae are noted for the first time in the suborder Troctomorpha. Both species of Chelyopsocus are probably parthenogenetic. The

C. Lienhard

1988-01-01

315

Programming in Java, Pizza and Python Extra Credit (not required)  

E-print Network

CS 538 Project #4 Programming in Java, Pizza and Python Extra Credit (not required) Not accepted an infinite LazyList containing val in // every position } static LazyList filter(LazyList control, Lazy (lazy lists and the ``Sieve of Erastosthenes'') in Python. Since Python is dynamically typed, you may

Fischer, Charles N.

316

University Extra-Mural Studies and Extension Outreach: Incompatibilities  

ERIC Educational Resources Information Center

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…

Rogers, Alan

2014-01-01

317

Extra-Curricular Activities and Academic Performance in Secondary Students  

ERIC Educational Resources Information Center

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…

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

2006-01-01

318

Origin of the extra chromosome No. 21 in Down's syndrome  

Microsoft Academic Search

Eighteen of 38 examined families with children with Down's syndrome showed polymorphisms of chromosome 21 elucidating the origin of the extra chromosome 21. Maternal origin was found in 10 cases and paternal origin in 8 cases. In both sexes errors occurred both in the first and in the second meiotic division.

P. Wagenbichler; W. Killian; A. Rett; W. Schnedl

1976-01-01

319

The functional significance of the extra-pyramidal systems  

Microsoft Academic Search

(A review of recent literature.) The extra-pyramidal systems have received by no means the attention given the pyramidal in years past; and the clinical observations and histopathological studies that have been given the former reveal a wealth of extraordinarily complicated and sometimes conflicting findings. The corpus striatum has been studied by different methods. Localized stimulation had led to mainly negative

F. T. Rogers

1927-01-01

320

Deviations from Newton's law in supersymmetric large extra dimensions  

NASA Astrophysics Data System (ADS)

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.

Callin, P.; Burgess, C. P.

2006-09-01

321

Health-Promoting Physical Activity and Extra-Curricular Sport  

ERIC Educational Resources Information Center

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

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

2007-01-01

322

Deviations From Newton's Law in Supersymmetric Large Extra Dimensions  

E-print Network

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.

P. Callin; C. P. Burgess

2005-11-17

323

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

324

Extra-articular Mimickers of Lateral Meniscal Tears  

PubMed Central

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

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

2011-01-01

325

46 CFR Sec. 8 - Extra work and changes.  

Code of Federal Regulations, 2013 CFR

...AUTHORITY MASTER LUMP SUM REPAIR CONTRACT-NSA-LUMPSUMREP Sec. 8 Extra work and...Change Order as provided in Article 6 of the NSA-LUMPSUMREP Contract. (c) A supplemental...completion date as provided in Article 27 of the NSA-LUMPSUMREP...

2013-10-01

326

Extra Processors versus Future Information in Optimal Deadline Scheduling  

E-print Network

Extra Processors versus Future Information in Optimal Deadline Scheduling #3; Chiu-Yuen Koo y Tak results extend the previous work that are primarily based on using a faster proces- sor to obtain be executed on more than one processor at the same time. Thus, a faster processor can speed up a job while

Wallach, Dan

327

Extra Processors versus Future Information in Optimal Deadline Scheduling  

E-print Network

Extra Processors versus Future Information in Optimal Deadline Scheduling Chiu-Yuen Koo Tak which are primarily based of using a faster processor to obtain a performance guarantee. The challenge at the same time. Thus, a faster processor can speed up a job while multiple unit-speed processors cannot help

Wallach, Dan

328

Extra processors versus future information in optimal deadline scheduling  

Microsoft Academic Search

This paper is concerned with the extra-resource analysis of online scheduling algorithms. In particular, it studies how to make use of multiple processors to counteract the lack of future information in online deadline scheduling. Our results extend the previous work that are primarily based on using a faster processor to obtain a performance guarantee. The challenge arises from the fact

Chiu-Yuen Koo; Tak-Wah Lam; Tsuen-Wan Ngan; Kar-Keung To

2002-01-01

329

Extra Credit assignment: the tattooed islanders problem Lewis Bowen  

E-print Network

Extra Credit assignment: the tattooed islanders problem Lewis Bowen Texas A&M University August 26. Not long after a person is born, their forehead is tattooed with a symbol; either a moon or a star. Custom forbids any discussion of the tattoos. Because there are no mirrors or reflective surfaces on the island

Bowen, Lewis

330

The trans-generational phase accumulation in the desert locust: morphometric changes and extra molting.  

PubMed

To understand the underlying trans-generational phase accumulation, a classical morphometric characteristic, the F/C ratio (F, hind femur length; C, maximum head width), of adult desert locusts (Schistocerca gregaria) was monitored over eight consecutive generations. Adult F/C ratios, which are larger in solitarious locusts than in gregarious ones, were negatively correlated to the darkness of body color at hatching. Two successive generations were required for a complete shift from the gregarious (crowd-reared) to the solitarious (isolated-reared) phase and vice versa in the laboratory. That is (1) female adults needed to be exposed to crowded (or isolated) conditions so that their hatchlings would become large (or small) and dark (or green) in color, and (2) the hatchlings then needed to be exposed to crowded (or isolated) conditions for their entire nymphal stage. Solitarious locusts exhibited extra molting that influenced the F/C ratio in the adult stage, but did not exert significant influences on the trans-generational changes in this trait because the incidence was low. The incidence of extra molting was negatively correlated with nymphal survival rates. The morphometric trans-generational changes may be explained without assuming any accumulating internal factor. PMID:19631213

Maeno, Koutaro; Tanaka, Seiji

2009-11-01

331

Deconvolving Terrestrial Alteration Mineral Spectral Signatures from Meteorite Reflectance Measurements  

NASA Technical Reports Server (NTRS)

When a meteorite enters into the earth's atmosphere, it is immediately subjected to various chemical reactions between its minerals and the elements in our thick atmosphere. These reactions alter the mineralogy of the meteorites. Some examples of the altered minerals in some meteorites are summarized. If meteorites can be linked to their corresponding parent body asteroid in space, we can improve our understanding of the solar system. Spectroscopy has been used in determining the links between asteroids and meteorites. However, meteorite weathering in the Earth s atmosphere also has an effect on meteorite spectra, and altered spectra can easily confuse asteroid connections. The goal of this project is to study the mineral and spectral changes due to Earth's environment and to design a computer simulation to correct meteorite spectra for the effects of terrestrial weathering.

Shah, Sweta; Clark, Beth Ellen; Hiroi, Takahiro; Zolensky, Michael

2004-01-01

332

A Possible Aeronomy of Extrasolar Terrestrial Planets  

E-print Network

Terrestrial planetary systems may exist around nearby stars as the Earth-sized counterparts to the many giant planets already discovered within the solar neighborhood. In this chapter we first discuss the numerous techniques which have been suggested to search for extrasolar terrestrial planets. We then focus on the expected results from that technique in which an orbiting telescope or interferometer is used to obtain a visible or infrared spectrum of a planet, without contamination from the parent star. We show examples of such spectra for selected cases: the present Earth, the Neoproterozoic (snowball) Earth, a methane-rich Earth, and the present Mars and Venus. We conclude by discussing the implications of such spectra for the detection of life on an extrasolar terrestrial planet.

W. A. Traub; K. W. Jucks

2002-05-22

333

A Possible Aeronomy of Extrasolar Terrestrial Planets  

E-print Network

Terrestrial planetary systems may exist around nearby stars as the Earth-sized counterparts to the many giant planets already discovered within the solar neighborhood. In this chapter we first discuss the numerous techniques which have been suggested to search for extrasolar terrestrial planets. We then focus on the expected results from that technique in which an orbiting telescope or interferometer is used to obtain a visible or infrared spectrum of a planet, without contamination from the parent star. We show examples of such spectra for selected cases: the present Earth, the Neoproterozoic (snowball) Earth, a methane-rich Earth, and the present Mars and Venus. We conclude by discussing the implications of such spectra for the detection of life on an extrasolar terrestrial planet.

Traub, W A

2002-01-01

334

Responses of terrestrial aridity to global warming  

NASA Astrophysics Data System (ADS)

dryness of terrestrial climate can be measured by the ratio of annual precipitation (P) to potential evapotranspiration (PET), where the latter represents the evaporative demand of the atmosphere, which depends on the surface air temperature, relative humidity, wind speed, and available energy. This study examines how the terrestrial mean aridity responds to global warming in terms of P/PET using the Coupled Model Intercomparison Project phase 5 transient CO2 increase to 2 × CO2 simulations. We show that the (percentage) increase (rate) in P averaged over land is ~1.7%/°C ocean mean surface air temperature increase, while the increase in PET is 5.3%/°C, leading to a decrease in P/PET (i.e., a drier terrestrial climate) by ~3.4%/°C. Noting a similar rate of percentage increase in P over land to that in evaporation (E) over ocean, we propose a framework for examining the change in P/PET, in which we compare the change in PET over land and E over ocean, both expressed using the Penman-Monteith formula. We show that a drier terrestrial climate is caused by (i) enhanced land warming relative to the ocean, (ii) a decrease in relative humidity over land but an increase over ocean, (iii) part of increase in net downward surface radiation going into the deep ocean, and (iv) different responses of PET over land and E over ocean for given changes in atmospheric conditions (largely associated with changes in temperatures). The relative contributions to the change in terrestrial mean aridity from these four factors are about 35%, 35%, 15%, and 15%, respectively. The slight slowdown of the surface wind over both land and ocean has little impact on the terrestrial mean aridity.

Fu, Qiang; Feng, Song

2014-07-01

335

Terrestrial impact melt rocks and glasses  

NASA Astrophysics Data System (ADS)

The effects of meteorite and comet impact on Earth are rock brecciation, the formation of shock metamorphic features, rock melting, and the formation of impact structures, i.e. simple craters, complex craters, and multi-ring basins. Large events, such as the 65-Ma Chicxulub impact, are believed to have had catastrophic environmental effects that profoundly influenced the development of life on Earth. In this review, an attempt is made to summarize some of the voluminous literature on impact melting, one important aspect of planetary impact, provide some comments on this process, and to make suggestions for future research. The products of impact melting are glasses, impact melt rocks, and pseudotachylites. Our treatise deals mainly with the geological setting, petrography, and major-element chemistry of melt rocks and glasses. Impact glasses, in several petrographic aspects, are similar to volcanic glasses, but they are associated with shock metamorphosed mineral and rock fragments and, in places, with siderophile element anomalies suggestive of meteoritic contamination. They are found in allogenic breccia deposits within (fall-back 'suevite') and outside (fall-out 'suevite') impact craters and, as spherules, in distal ejecta. Large events, such as the K/T boundary Chicxulub impact, are responsible for the formation of worldwide ejecta horizons which are associated with siderophile element anomalies and shock metamorphosed mineral and rock debris. Impact glasses have a bulk chemical composition that is homogeneous but exemptions to this rule are common. On a microscopic scale, however, impact glasses are commonly strikingly heterogeneous. Tektites are glasses ejected from craters over large distances. They are characterized by very low water and volatile contents and element abundances and ratios that are evidence that tektites formed by melting of upper crustal, sedimentary rocks. Four tektite strewn-fields are known, three of which can be tied to specific impact craters. Impact melt rocks form sheets, lenses, and dike-like bodies within or beneath allogenic fallback breccia deposits in the impact crater and possibly on crater terraces and flanks. Dikes of impact melt rocks also intrude the rocks of the crater floor. They commonly contain shock metamorphosed target rock and mineral fragments in various stages of assimilation and are glassy or fine- to coarse-grained. Chemically, they are strikingly homogeneous, but as with impact glasses, exemptions to this rule do exist. Large and thick melt bodies, such as the Sudbury Igneous Complex (SIC), are differentiated or may represent a combination of impact melt rocks sensu-strictu and impact-triggered, deep-crustal melts. A concerted, multidisciplinary approach to future research on impact melting and on other aspects of meteorite and comet impact is advocated. Impact models are models only and uncritical reliance on their validity will not lead to a better understanding of impact processes—especially of melting, excavation, and deposition of allogenic breccias and the spatial position of breccias in relation to sheets and lenses of melt rocks within the crater. Impact-triggered pressure-release melting of target rocks beneath the excavation cavity may be responsible for the existence of melt rocks beneath the impact melt rocks sensu-strictu. This controversial idea needs to be tested by a re-evaluation of existing data and models, be they based on field or laboratory research. Only a relatively small number of terrestrial impact structures has been investigated in sufficient detail as it relates to geological and geophysical mapping. In this review, we summarize observations made on impact melt rocks and impact glasses in a number of North American (Brent, Haughton, Manicouagan, New Quebec, Sudbury, Wanapitei, all in Canada), Asian (Popigai, Russia; Zhamanshin, Kazakhstan), two South African structures (Morokweng and Vredefort), the Henbury crater field of Australia, and one European crater (Ries, Germany). Our tables listing major-element chemical compositions of impact

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

2001-12-01

336

Solar-Terrestrial Science Strategy Workshop  

NASA Technical Reports Server (NTRS)

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.

Banks, Peter M. (editor); Roberts, William T. (editor); Kropp, Jack (editor)

1989-01-01

337

Tectonic Evolution of the Terrestrial Planets  

NASA Technical Reports Server (NTRS)

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.

Solomon, Sean C.; Senski, David G. (Technical Monitor)

2002-01-01

338

The development of early terrestrial ecosystems  

E-print Network

of subaerial diagenesis in the 1.2-b.y. Mescal Limestone, central Arizona: implications for the timing and development of a terrestrial plant cover. Geological Society of America, Bulletin 96,737-745. THE DEVELOPMENT OF EARLY TERRESTRIAL ECOSYSTEMS 355 Bell..., P.R. (1989). 'Heterospory' in Sphagnum: fifty years of error. Journal of Bryology 15, 679-682. Berkner, L.V. & Marshall, L.C. (1965). On the origin and rise of oxygen concentration in the Earth's atmosphere. Journal of Atmospheric Science 22...

Selden, Paul A.; Edwards, Dianne

1993-01-01

339

Monogenetic volcanoes of the terrestrial planets  

NASA Technical Reports Server (NTRS)

Monogenetic volcanic activity has produced cinder cones and small shield volcanoes on the earth, moon, and Mars. Extraterrestrial cinder cones have median volumes only 25% as large as average terrestrial cinder cones, implying that their magma chambers are smaller and shallower (1 km depth vs 3 km). Ejection velocities for lunar and Martian cinder cones range from 20 to 70 m/sec, only 1/3 to 1/10 as high as for equal volume terrestrial eruptions. These low velocities imply low volatile contents for both Martian and lunar magmas.

Wood, C. A.

1979-01-01

340

Body Satisfaction  

PubMed Central

Background Melanoma and obesity have both increased in recent years. Given the propensity of body dissatisfaction among the obese, the objectives of this paper were to determine how body satisfaction might influence skin examination and to examine differences in this relationship by gender among the participants of Check-It-Out, a study to increase thorough skin self-examination (TSSE). Methods Through primary care offices, 2126 participants were recruited from April 2000 to November 2001 for the baseline cross-sectional telephone data from the Check-It-Out study. TSSE was defined as the self-reported examination of all seven key areas of the body. Body satisfaction was reported based on the degree of disagreement or agreement with the statement I like the way my body looks. Analyses were conducted in 2005 and 2006. Results Among participants, 18% reported performing TSSE, 34% were normal or underweight, 36% were overweight, and 30% were obese. Overall, 23% strongly agreed, 45% somewhat agreed, 19% somewhat disagreed, and 12% strongly disagreed with the statement I like the way my body looks. Body satisfaction was less common among women than men. The odds of conducting TSSE were 1.6 for the total sample (1.9 for women and 1.2 for men) for those with strong agreement that they like the way their body looks. In multivariate analysis, body satisfaction was associated with TSSE performance for women and both genders together, along with the availability of a partner (both genders together and men), the availability of a wall mirror, the advice of a physician, and the use of glasses or contacts(women only). Conclusions Body satisfaction is an important factor in TSSE performance, especially among women, and should be considered along with other risk factors. PMID:18541179

Risica, Patricia Markham; Weinstock, Martin A.; Rakowski, William; Kirtania, Usree; Martin, Rosemarie A.; Smith, Kevin J.

2008-01-01

341

Cold adaptation of the terrestrial isopod, Porcellio scaber , to subnivean environments  

Microsoft Academic Search

The terrestrial isopod, Porcellio scaber, was susceptible to subzero temperature: both freezing and chilling were injurious. The level of cold hardiness against chilling and freezing showed different patterns in their seasonal variation. The lower lethal temperature causing 50% mortality, an indicator of the tolerance to chilling, ranged from-1.37°C in August to-4.58°C in December. The whole body supercooling point, the absolute

K. Tanaka; T. Udagawa

1993-01-01

342

Elevated Trace Element Concentrations in Southern Toads, Bufo terrestris, Exposed to Coal Combustion Waste  

Microsoft Academic Search

.   A number of recent studies have linked developmental, physiological, and behavioral abnormalities in amphibians to coal\\u000a combustion wastes (coal ash). Few studies, however, have determined trace element concentrations in amphibians exposed to\\u000a coal ash. In the current study we compare total body concentrations of 20 trace elements in adult southern toads, Bufo terrestris, inhabiting coal ash settling basins with

W. A. Hopkins; M. T. Mendonça; C. L. Rowe; J. D. Congdon

1998-01-01

343

Distribution of FMRFamide-like immunoreactivity in the nervous system of Lumbricus terrestris  

Microsoft Academic Search

The distribution of FMRFamide-like immunoreactive cell bodies and fibers in the nervous system of the earthworm Lumbricus terrestris has been studied by means of immunocytochemistry. The cerebral ganglion contains 150-170 immunoreactive nerve cells that are organized into six major groups in the rostral and five major groups in the caudal part of the ganglion; 160-180 immunoreactive nerve cells are present

Dóra Reglödi; S. Slezák; Andrea Lubics; Márta Szelier; K. Elekes; I. Lengvári

1997-01-01

344

Visible Body  

NSDL National Science Digital Library

The human body is an intricate, and often mysterious, place. With today's technology, however, many websites and apps provide entry into this fascinating world. Visible Body is one of the more compelling avenues for exploration. While there are paid products on the site, some of the content is available at no charge. Visitors can look over the Human Anatomy Atlas, which contains a range of visualizations that allow users to explore body systems in exquisite detail. For a small fee, users may access the other specific areas of the site, which include Digestive Anatomy, Respiratory Anatomy, and Reproductive & Urinary Anatomy.

345

In-line digital holographic microscopy for terrestrial and exobiological research  

NASA Astrophysics Data System (ADS)

We describe here a simple digital in-line holographic microscope (DIHM) that was used to investigate the microbial life forms that exist in perennial springs and glacial melt-water pools on Axel Heiberg Island at near 80°N latitude in the Canadian High Arctic. The instrument determined an upper limit of the density of microbial organisms in the springs and also found an abundance of algae and bacteria in the pools formed from glacial run off. The discovery of life in extra-terrestrial regions of our solar system has been the aim of several space missions. DIHM can capture the dynamics of objects throughout an imaging volume with wavelength limited resolution. The simplicity of DIHM technology furthermore allows the construction of very light-weight and rugged instruments that we believe can be easily adapted for space missions and exobiological studies.

Jericho, S. K.; Klages, P.; Nadeau, J.; Dumas, E. M.; Jericho, M. H.; Kreuzer, H. J.

2010-03-01

346

Terrestrial Planet Formation in the ? Centauri System  

Microsoft Academic Search

We examine the late stages of terrestrial planet formation around each star in theCentauri A and ? Centauri B binary system. Each integration begins with a '' bimodal '' mass distribution of 14 large embryos embedded in a disk of smaller planetesimals orbiting one of the stars. These initial conditions were chosen because when they are used in simulations about

Elisa V. Quintana; Jack J. Lissauer; John E. Chambers; Martin J. Duncan

2002-01-01

347

High efficiency, long life terrestrial solar panel  

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

348

Consumer strategies of terrestrial gastropods and isopods  

Microsoft Academic Search

Morphological, physiological and ecological evidence is used to show that terrestrial gastropods and isopods, although both can be considered as “primary consumers”, deal quite differently with the vegetabilic matter they use as food. Gastropods are both efficient digesters and assimilators whereas isopods are efficient digesters but usually inefficient assimilators. This combination may require the isopods to turn to coprophagy as

Wolfgang Wieser

1978-01-01

349

Extraterrestrial amino acids and terrestrial life  

NASA Astrophysics Data System (ADS)

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)

Chyba, Christopher F.

1996-07-01

350

Moon and Terrestrial Planets: Unresolved Questions  

Microsoft Academic Search

Human exploration during Apollo began the documentation of the evolution of the Moon and of its importance in understanding the origin and evolution of the terrestrial planets. This revolution in planetary geology continues as a vigorous and vibrant arena for discovery and debate for new generations of geoscientists. Although much has been learned and, indeed, resolved in lunar science, we

H. H. Schmitt

2002-01-01

351

Oil Pollution in the Antarctic Terrestrial Environment  

Microsoft Academic Search

2 Abstract: Fuel oil has been extensively relied upon as an energy source since the earliest discovery and exploration of Antarctica. During this time oil spills have occurred, particularly around established research stations, which have had a negative impact on the terrestrial environment. Recently developed bioremediative technology, using indigenous Antarctic hydrocarbon-degrad- ing bacteria, may be used to assist in cleaning

Kevin A. Hughes; Bethan Stallwood

352

Hot oxygen coronas at terrestrial planets  

Microsoft Academic Search

Solar forcing via both influx of the solar wind plasma and absorption of ultraviolet radiation forms the hot oxygen coronas at the terrestrial planets (Shizgal and Arcos, 1996). These coronas were observed in the past and recent planetary space missions (Mariner, Pioneer Venus, IMAGE, Mars Express and etc.). We will dicsuss the relative role of the following energetic processes determining

V. I. Shematovich; R. E. Johnson

2006-01-01

353

A concept of digital terrestrial television broadcasting  

Microsoft Academic Search

The future terrestrial television broadcasting system should support the transmission of a digital HDTV signal with a high spectral efficiency. In addition, this system should maintain graceful degradation as the actual analog systems, and should be compatible with the SDTV. The system compatibility can be achieved by using a hierarchical HDTV source-coding scheme that can provide at least two (HDTV,

K. Fazel; S. Kaiser; P. Robertson; M. J. Ruf

1995-01-01

354

Spaceprobe images and the Terrestrial Planets Section  

Microsoft Academic Search

With the formation of a new grouping within the Association - the Terrestrial Planets Section - there is scope for a fresh approach to BAA studies of Mercury, Venus and Mars, incorporating both Earth-based and spacecraft-derived information. Printing Options Send high resolution image to Level 2 Postscript Printer Send low resolution image to Level 2 Postscript Printer Send low resolution

G. J. Day

1981-01-01

355

Thin film solar cells for terrestrial applications  

Microsoft Academic Search

A design has evolved from an earlier space cell which is promising for large scale terrestrial use. This is a front wall cell on zinc plated copper foil substrate with an evaporated grid and an integral glass cover formed by r.f. sputtering. This cell is suitable for low cost mass fabrication. Though it has not been fully proven it combines

F. A. Shirland; W. J. Biter; E. W. Greeneich; A. J. Simon; T. P. Brody

1977-01-01

356

Subsolidus convective cooling histories of terrestrial planets  

Microsoft Academic Search

The subsolidus convective cooling histories of terrestrial planets evolving from hot initial states are investigated quantitatively. A simple analytic model simulating average heat flux from a vigorously convecting mantle and incorporating a mantle viscosity proportional to mantle temperature and a lithosphere which thickens as the planet cools is employed. Heat flux from the convecting mantle is calculated on the basis

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

1979-01-01

357

UV-B EFFECTS ON TERRESTRIAL ECOSYSTEMS  

EPA Science Inventory

Dpeletion of stratospheric O3 layer should result in enhanced levels of ultraviolet-B (UV-B) radiation at the earth's surface compared to present, with potentially damaging effects on biological systems. his paper briefly summarizes some key findings for UV-B effects on terrestri...

358

The geophysical signature of terrestrial impact craters  

Microsoft Academic Search

Terrestrial impact craters are examined in terms of their geophysical characteristics which can be used to identify additional impact craters. The geophysical signatures examined include the circular gravity low which is modeled for the cases of bowl-shaped and complex craters. The size of the gravity anomaly for both types of craters is established and modeled with known morphometric parameters of

M. Pilkington; R. A. F. Grieve

1992-01-01

359

Physics Classroom: Drawing Free-Body Diagrams  

NSDL National Science Digital Library

This tutorial explains how free body diagrams are used in solving problems involving Newton's Second Law. This tutorials demonstrates how to draw free body diagrams, what the diagram means to Physics, and includes practice problems for the student. This tutorial also includes other tutorials, animations, and student activities in other concepts of Physics. The Physics Classroom is a set of resources created for learners and teachers of high school physics. It includes comprehensive tutorials, problem sets with solutions, extra help for struggling students, Shockwave animations, multimedia learning modules, labs, and photo gallery.

Henderson, Tom

2011-10-03

360

Interactive Body  

MedlinePLUS

... Body '); } else { document.write(' You must have atleast Adobe Flash Player 10 installed on your computer to view this application. Please download Adobe Flash Player 10 now. '); } //--> Virtually every organ system is ...

361

Foreign Body  

MedlinePLUS

... could easily become foreign bodies. Young children commonly swallow food (meats, nuts, seeds, candy, fruit pits, and ... check stools for the coin. Usually when children swallow things (even sharp objects such as pins and ...

362

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 ...

363

Body Hygiene  

MedlinePLUS

... Challenges and Resources Hygiene-related Diseases Athlete's Foot (tinea pedis) Body Lice Chronic Diarrhea Dental Caries Head ... Tub Rash Lymphatic Filariasis Pinworms Pubic Lice ("Crabs") Ringworm (Tinea) Swimmer's Ear (otitis externa) Scabies Trachoma Information ...

364

Study on Extra Heavy Oil Gasification Reaction Process  

NASA Astrophysics Data System (ADS)

From the viewpoints of global environment and energy security, raising the thermal efficiency of a thermal power plant and the diversification of fuel are issues that must be resolved as soon as possible. As to resolving these two issues, it is very effective that extra heavy oil is used in a gas-steam combined cycle power generation system. Accordingly, in order to establish technology for supporting to rationally design and operate a gasifier using extra heavy oil, the Central Research Institute of Electric Power Industry (CRIEPI) targeted at clarifying significant phenomena in a gasifier, improving the accuracy of numerical analytical technique under development and verifying the technique. This report describes the major specifications of “Research Gasifier for Liquid Fuel” constructed in 1999 and the results of studies in respect to the reaction process in the gasifier based on OrimulsionTM (Trademark of BITOR) gasification tests in 2000.

Kidoguchi, Kazuhiro; Hara, Saburo; Ashizawa, Masami; Inumaru, Jun

365

Extra thin alginate film: an efficient technique for protoplast culture.  

PubMed

This paper reports an efficient protoplast culture technique, the "extra thin alginate film" technique. The development of this improved method of protoplast culture was an outcome of an assessment of the efficiency and shortcomings of various protoplast culture techniques. The efficiency of this technique was evaluated with two model plant systems, viz., Nicotiana tabacum and Lotus corniculatus, and a comparison was made with the "thin alginate layer" technique, another efficient protoplast culture system. Results indicate that the culture technique with extra thin alginate film is as efficient as the technique with thin alginate layer, with many additional advantages. The present innovation overcomes most of the limitations of protoplast culture techniques described so far and can now be applied to a wide variety of crops to check its general applicability. PMID:16244810

Pati, P K; Sharma, Madhu; Ahuja, Paramvir Singh

2005-12-01

366

QCD parity violation at LHC in warped extra dimension  

NASA Astrophysics Data System (ADS)

An extra dimension is one of the most attractive candidates beyond the Standard Model. In warped extra dimensional space-time, not only the gauge hierarchy problem but also quark-lepton mass hierarchy can be naturally explained. In this setup, a sizable parity violation through a Kaluza-Klein gluon exchange appears in the QCD process such as helicity dependent top pair production. We investigate this QCD parity violating process by use of the SO(5)×U(1) gauge-Higgs unification model. We evaluate LHC observable quantities, i.e., a charge asymmetry and a forward-backward asymmetry of the top pair production, and find that a sizable charge asymmetry can be observed with specific model parameters.

Haba, Naoyuki; Kaneta, Kunio; Tsuno, Soshi

2013-05-01

367

Extra dimensions and neutrinoless double beta decay experiments  

SciTech Connect

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.

Gozdz, Marek; Kaminski, Wieslaw A.; Faessler, Amand [Theoretical Physics Department, Maria Curie-Sklodowska University, Lublin (Poland); Institute fuer Theoretische Physik, Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

2005-05-01

368

Evolution of the terrestrial planets (geological and petrological data)  

NASA Astrophysics Data System (ADS)

How the terrestrial solid planetary bodies were developed? What major stages of their irreversible evolution took place before they turned into "dead" stone balls? We discuss these problems on examples of the Earth and the Moon, which evolution studied the best. According to modern views, after accretion of these bodies, magma oceans of some hundreds km deep appeared on their surface. According to Jeffries (1929), solidification of large molted bodies, because of the difference between adiabatic gradient in silicate melts (0.3oC/km) and gradient of their melting points (3oC/km), could be going only upwards, from the bottom to the surface. As a result a powerful crystallizing differentiation of the oceans' magmas took place with accumulation of the most low-melting components to the surface. Due to different deep of the oceans on the Moon and the Earth, the primordial crusts on these bodies were rather different: mafic on the Moon and sialic on the Earth. Geological evolution of the Earth began 4 Ga ago from appearance of Archean granite-greenstone terranes (GGT) and divided them granulite belts. Mantle-derived magmatism of high-Mg komatiite-basaltic series was located in greenstone belts, which formed irregular network within GGTs and composed 10-15 The sharp change of the magmatic activity with appearance in global scale of geochemical-enriched Fe-Ti picrites and basalts occurred in interval 2.3-2.0 Ga ago. Such melts was typical for Phanerozoic within-plate magmatism and linked with thermochemical mantle plumes of the second generation, which ascended from the liquid core-mantle boundary (CMB). It was followed by plate tectonic appearance 2 Ga ago and from this particular time such tectonic regime has existed till now. From this particular time, ancient Earth's continental crust began to involved in subduction processes and interchange by secondary oceanic crust which forms about 70Where this geochemical-enriched material was conserved and how it was activated? We suggest that such situation could be possible only in case when (1) accretion of the Earth was heterogeneous, and (2) warming of the Earth occurred downwards, from surface to core. It was, probably, a result of moving inwards a wave of deformations, accompanied by emission of heat. At the first stage the wave went through depleted (in result of directed solidification of magma ocean) mantle and led to appearance of mantle superplumes of the first generation. At the second stage it reached iron core, melted it, which led to appearance of mantle supeplumes of the second generation (thermochemical), enriched in fluids, Fe, Ti, alcalies, incompatible elements, etc. Material of such superplumes could rich more shallow levels and led to active interactions of their extended heads with solid lithosphere, which caused changing of tectonic activity character. We suggest that terrestrial planets were developed at the same, but shortened scenario, and more quick. At the Moon the earliest magmatism of highlands were close to terrestrial early Paleoproterozoic SHMS and at the boundary 3.9-3.8 Ga ago was changed by maria magmatism, close in composition to MORB and OIB. By analogy with the Earth, we suggest that maria magmatism was linked with ascending of thermochemical superplumes, generated at the lunar CMB, when it's liquid iron core was yet existed. Ancient planums on Mars and tesseras at the Venus among vast planides, composed by basaltic flows can also evidence about two stages of their development. Judging on absence of magnetic field, their liquid cores ("energetic hearts") are of no consequence and they are dead bodies now. Work was supported by grant RFBR 07-05-00496

Sharkov, Evgenii

369

Universal extra dimensions and the Higgs boson mass  

Microsoft Academic Search

We study the combined constraints on the compactification scale 1\\/R and the Higgs boson mass mH in the standard model with one or two universal extra dimensions. Focusing on precision measurements and employing the Peskin-Takeuchi S and T parameters, we analyze the allowed region in the (mH,1\\/R) parameter space consistent with current experiments. For this purpose, we calculate complete one-loop

Thomas Appelquist; Ho-Ung Yee

2003-01-01

370

Search for Universal Extra Dimensions in pp[over ¯] Collisions  

Microsoft Academic Search

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⁻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

V. M. Abazov; S. J. de Jong; F. Filthaut; M. M. Meijer; L. Zivkovic; Alexeev G. D; Alkhazov G; Alton A; Alverson G; Aoki M; Askew A; Asman B; Atkins S; Atramentov O; Augsten K; Avila C; BackusMayes J; Badaud F; Bagby L; Baldin B; Bandurin D. V; Banerjee S; Barberis E; Baringer P; Barreto J; Bartlett J. F; Bassler U; Bazterra V; Bean A; Begalli M; Belanger-Champagne C; Bellantoni L; Beri S. B; Bernardi G; Bernhard R; Bertram I; Besancon M; Beuselinck R; Bezzubov V. A; Bhat P. C; Bhatia S; Bhatnagar V; Blazey G; Blessing S; Bloom K; Boehnlein A; Boline D; Boos E. E; Borissov G; Bose T; Brandt A; Brandt O; Brock R; Brooijmans G; Bross A; Brown D; Brown J; Bu X. B; Buehler M; Buescher V; Bunichev V; Burdin S; Burnett T. H; Buszello C. P; Calpas B; Camacho-Perez E; Carrasco-Lizarraga M. A; Casey B. C. K; Castilla-Valdez H; Chakrabarti S; Chakraborty D; Chan K. M; Chandra A; Chapon E; Chen G; Chevalier-Thery S; Cho D. K; Cho S. W; Choi S; Choudhary B; Cihangir S; Claes D; Clutter J; Cooke M; Cooper W. E; Corcoran M; Couderc F; Cousinou M-C; Croc A; Cutts D; Das A; Davies G; de Jong S. J; De La Cruz-Burelo E; Deliot F; Demina R; Denisov D; Denisov S. P; Desai S; Deterre C; DeVaughan K; Diehl H. T; Diesburg M; Ding P. F; Dominguez A; Dorland T; Dubey A; Dudko L. V; Duggan D; Duperrin A; Dutt S; Dyshkant A; Eads M; Edmunds D; Ellison J; Elvira V. D; Enari Y; Evans H; Evdokimov A; Evdokimov V. N; Facini G; Ferbel T; Fiedler F; Fisher W; Fisk H. E; Fortner M; Fox H; Fuess S; Garcia-Bellido A; Garcia-Guerra G. A; Gavrilov V; Gay P; Geng W; Gerbaudo D; Gerber C. E; Gershtein Y; Ginther G; Golovanov G; Goryachev V. N; Goussiou A; Grannis P. D; Greder S; Greenlee H; Greenwood Z. D; Gregores E. M; Grenier G; Gris Ph; Grivaz J-F; Grohsjean A; Gruenendahl S; Gruenewald M. W; Guillemin T; Gutierrez G; Gutierrez P; Haas A; Hagopian S; Haley J; Han L; Harder K; Harel A; Hauptman J. M; Hays J; Head T; Hebbeker T; Hedin D; Hegab H; Heinson A. P; Heintz U; Hensel C; Heredia-De La Cruz I; Herner K; Hesketh G; Hildreth M. D; Hirosky R; Hoang T; Hobbs J. D; Hoeneisen B; Hohlfeld M; Hubacek Z; Hynek V; Iashvili I; Ilchenko Y; Illingworth R; Ito A. S; Jabeen S; Jaffre M; Jamin D; Jayasinghe A; Jesik R; Johns K; Johnson M; Jonckheere A; Jonsson P; Joshi J; Jung A. W; Juste A; Kaadze K; Kajfasz E; Karmanov D; Kasper P. A; Katsanos I; Kehoe R; Kermiche S; Khalatyan N; Khanov A; Kharchilava A; Kharzheev Y. N; Kohli J. M; Kozelov A. V; Kraus J; Kulikov S; Kumar A; Kupco A; Kurca T; Kuzmin V. A; Lammers S; Landsberg G; Lebrun P; Lee H. S; Lee S. W; Lee W. M; Lellouch J; Li H; Li L; Li Q. Z; Lietti S. M; Lim J. K; Lincoln D; Linnemann J; Lipaev V. V; Lipton R; Liu Y; Lobodenko A; Lokajicek M; de Sa R. Lopes; Lubatti H. J; Luna-Garcia R; Lyon A. L; Maciel A. K. A; Mackin D; Madar R; Magana-Villalba R; Malik S; Malyshev V. L; Mansour J; Maravin Y; Martinez-Ortega J; McCarthy R; McGivern C. L; Melnitchouk A; Menezes D; Mercadante P. G; Merkin M; Meyer A; Meyer J

2012-01-01

371

The Merits of Giving an Extra Credit Quiz  

ERIC Educational Resources Information Center

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…

Carroll, Ryall

2014-01-01

372

Extra phase noise from thermal fluctuations in nonlinear optical crystals  

E-print Network

We show theoretically and experimentally that scattered light by thermal phonons inside a second-order nonlinear crystal is the source of additional phase noise observed in Optical Parametric Oscillators. This additional phase noise reduces the quantum correlations and has hitherto hindered the direct production of multipartite entanglement in a single nonlinear optical system. We cooled the nonlinear crystal and observed a reduction of the extra noise. Our treatment of this noise can be successfully applied to different systems in the literature.

J. E. S. Cesar; A. S. Coelho; K. N. Cassemiro; A. S. Villar; M. Lassen; P. Nussenzveig; M. Martinelli

2009-06-22

373

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

PubMed

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

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

2013-04-01

374

Experimental investigation of the behavior of extra high strength steel  

Microsoft Academic Search

This paper comprises a study concerning the mechanical behavior of extra high strength steel. This is investigated by means\\u000a of biaxial testing of flat cross-shaped specimens in the full ?1-?2 plane, a concept developed earlier at Steel Structures, Lule University of Technology. Furthermore, new specimen designs\\u000a had to be developed to enable testing of a material with high yield strength

J. Gozzi; A. Olsson; O. Lagerqvist

2005-01-01

375

Newton's law in braneworlds with an infinite extra dimension  

Microsoft Academic Search

We study the behavior of the four-dimensional Newton's law in warped braneworlds. The setup considered here is a (3+n)-brane embedded in 5+n dimensions, where n extra dimensions are compactified and a dimension is infinite. We show that the wave function of gravity is described in terms of the Bessel functions of 2+n\\/2 order and that estimate the correction to Newton's

Masato Ito

2002-01-01

376

Newton's law in braneworlds with an infinite extra dimension  

E-print Network

We study the behavior of the four$-$dimensional Newton's law in warped braneworlds. The setup considered here is a $(3+n)$-brane embedded in $(5+n)$ dimensions, where $n$ extra dimensions are compactified and a dimension is infinite. We show that the wave function of gravity is described in terms of the Bessel functions of $(2+n/2)$-order and that estimate the correction to Newton's law. In particular, the Newton's law for $n=1$ can be exactly obtained.

Masato Ito

2001-12-23

377

Extra-articular hip endoscopy: A review of the literature.  

PubMed

The aim of this review is to evaluate the current available literature evidencing on peri-articular hip endoscopy (the third compartment). A comprehensive approach has been set on reports dealing with endoscopic surgery for recalcitrant trochanteric bursitis, snapping hip (or coxa-saltans; external and internal), gluteus medius and minimus tears and endoscopy (or arthroscopy) after total hip arthroplasty. This information can be used to trigger further research, innovation and education in extra-articular hip endoscopy. PMID:23610664

Verhelst, L; Guevara, V; De Schepper, J; Van Melkebeek, J; Pattyn, C; Audenaert, E A

2012-12-01

378

Rare case of multifocal (adrenal and extra - adrenal ) myelolipoma.  

PubMed

Adrenal myelolipoma is an extremely rare lesion, which is composed of adipose and hematopoetic tissue. The above-mentioned lesion was first described by Gierke in 1905, with the term myelolipoma used for the first time by Oberling in 1929. The Authors of the study presented a case of a 57 year-old female patient diagnosed with a multifocal adrenal and extra- adrenal myelolipoma. PMID:23828417

Bandurski, Roman; Zar?ba, Konrad; K?dra, Bogus?aw

2013-06-01

379

Extra Processors versus Future Information in Optimal Deadline Scheduling  

Microsoft Academic Search

This paper is concerned with the design of online scheduling algorithms that exploit extra resources. In particular, it studies\\u000a how to make use of multiple processors to counteract the lack of future information in online deadline scheduling. Our results\\u000a extend the previous work that are primarily based on using a faster processor to obtain a performance guarantee. The challenge\\u000a arises

Chiu-yuen Koo; Tak-Wah Lam; Tsuen-Wan \\ Ngan; Kar-keung To

2004-01-01

380

76 FR 50274 - Terrestrial Environmental Studies for Nuclear Power Stations  

Federal Register 2010, 2011, 2012, 2013

...Terrestrial Environmental Studies for Nuclear Power Stations AGENCY: Nuclear Regulatory...Terrestrial Environmental Studies for Nuclear Power Stations.'' This guide provides...supporting licensing decisions for nuclear power reactors. DATES: Submit...

2011-08-12

381

77 FR 18271 - Terrestrial Environmental Studies for Nuclear Power Stations  

Federal Register 2010, 2011, 2012, 2013

...Terrestrial Environmental Studies for Nuclear Power Stations AGENCY: Nuclear Regulatory...Terrestrial Environmental Studies for Nuclear Power Stations.'' This guide provides...supporting licensing decisions for nuclear power reactors. ADDRESSES:...

2012-03-27

382

Center for Research on Enhancing Carbon Sequestration in Terrestrial Ecosystems  

E-print Network

#12;Center for Research on Enhancing Carbon Sequestration in Terrestrial Ecosystems Personnel. Blaine Metting #12;vii Abstract The Center for Research on Enhancing Carbon Sequestration in Terrestrial needed to evaluate the feasibility of environmentally sound strategies for enhancing carbon sequestration

383

XQCAT: eXtra Quark Combined Analysis Tool  

E-print Network

XQCAT (eXtra Quark Combined Analysis Tool) is a tool aimed to determine exclusion Confidence Levels (eCLs) for scenarios of new physics characterised by the presence of one or multiple heavy extra quarks (XQ) which interact through Yukawa couplings with any of the Standard Model (SM) quarks. The code uses a database of efficiencies for pre-simulated processes of Quantum Chromo-Dynamics (QCD) pair production and on-shell decays of extra quarks. In the version 1.0 of XQCAT the efficiencies have been computed for a set of seven publicly available search results by the CMS experiment, and the package is subject to future updates to include further searches by both ATLAS and CMS collaborations. The input for the code is a text file in which masses, branching ratios (BRs) and dominant chirality of the couplings of the new quarks are provided. The output of the code is the eCL of the test point for each implemented experimental analysis considered individually and, when possible, in statistical combination.

Barducci, D; Buchkremer, M; Marrouche, J; Moretti, S; Panizzi, L

2014-01-01

384

Cytokeratin expression in adrenal phaeochromocytomas and extra-adrenal paragangliomas.  

PubMed Central

AIM: To examine whether adrenal phaeochromocytomas and extra-adrenal paragangliomas are immunoreactive for commercially available and routinely used cytokeratin antibodies. METHODS: 18 extra-adrenal paragangliomas and seven adrenal phaeochromocytomas were stained with CAM 5.2, AE1/3, and 34 beta E12 following microwave antigen retrieval of formalin fixed tissue. RESULTS: A single case from the cauda equina was positive for both CAM 5.2 and AE1/3. In addition, two other cases--an intravagal and an orbital paraganglioma--also showed strong immunopositivity with CAM 5.2 and AE1/3. All phaeochromocytomas were negative with all epithelial markers. CONCLUSIONS: Cauda equina paragangliomas are known to stain with cytokeratins; however, occasional paragangliomas from other sites may also be immunoreactive with cytokeratins. If the results of immunohistochemistry are not interpreted in the clinical and morphological context, the failure to recognise that extra-adrenal paragangliomas may on occasion react with anticytokeratin antibodies may lead to their being confused with metastatic carcinomas. Images PMID:9771451

Chetty, R; Pillay, P; Jaichand, V

1998-01-01

385

Study of terrestrial ages of the Antarctic meteorites with thermoluminescence  

NASA Astrophysics Data System (ADS)

The terrestrial ages of Antarctic meteorites were estimated from the thermoluminescence (TL) intensity of the fusion crest. It was found that there is a good correlation between the TL intensities and terrestrial ages which were previously measured by cosmogenic-radionuclide abundance. It was also noticed that the LT/HT value gives false terrestrial ages. The basis for establishing the TL dating techniques regarding the terrestrial ages of Antarctic meteorites is presented.

Miono, S.; Nakanishi, A.

1993-04-01

386

Terrestrial Television Broadcasting in China: Technologies and Applications  

Microsoft Academic Search

\\u000a This chapter will discuss the two main terrestrial television broadcasting systems widely used in China. One is the China\\u000a Terrestrial Television Broadcasting (CTTB) standard which is named as “Frame structure, channel coding and modulation for\\u000a digital television terrestrial broadcasting system”. It was issued in August 2006 as a mandatory standard for traditional\\u000a terrestrial broadcasting and had been put into execution

Wenjun Zhang; Yunfeng Guan; Xiaokang Yang; Weiqiang Liang

2010-01-01

387

Abiogenic synthesis on terrestrial orbit  

NASA Astrophysics Data System (ADS)

Meteorites probably played a central role in the evolution of life. Due to the structure, they tend to adsorb organic compounds and catalyze a variety of organic reactions critical to scenarios of life’s origins. We have shown experimentally that extraterrestrial minerals can catalyze the formation of peptides and nucleotides. The present study was performed onboard different Russian space stations (BION, COSMOS, and MIR) with various duration, altitude, and radiation conditions. Irradiation of solid samples, free or admixed with certain minerals, was the major task of future space flight experiments, planned for performing onboard Russian space satellite Bion-M. The «simulated space ice conditions» experiments have shown the synthesis of simple biochemical compounds in the form of amino acid’s precursors and pyrimidine bases (uracil, cyrosine and thymine) of the nucleic acids. Our investigation dealt with further reaction of nucleic acid components to nucleotides - main components of RNA and DNA, and single aminoacids to oligopeptides. We investigated two types of reactions: (1) abiogenic synthesis of nucleotides from mixtures of nucleoside + inorganic phosphate; (2) abiogenic synthesis of dipeptides from mixtures of simple amino acids. The reaction mixture in the form of a solid film contains (1) nucleoside and dihydrogen phosphate; (2) two different amino acids. Seven different nucleosides (thymidine, cytidine, uracil, adenosine or deoxyadenosine, guanosine or deoxyguanosine) and four mixtures of aromatic (tyrosine or triptophan) and aliphatic (glycine or alanine) amino acids were investigated. Mixtures were irradiated as solid films with different sources of energy: (1) VUV-light of 145 nm; (2) high energy protons (2-6 MeV); and (3) were installed on the surface of biosputnik in outstanding container when they were exposed to the action of all spectra of the open space energy sources during the entire time of flight. We have shown experimentally that the solid mixtures of amino acids produce more complex compounds when they are exposed to open space energy sources. Both irradiation and photolysis may destroy molecules as well as allow the synthesis of new and more complex ones. In space flight experiments onboard of «BION»-type satellites the solid films from mixtures of different nucleosides and inorganic phosphate or mixtures of amino acids were exposed to space conditions. The abiogenic synthesis of the full set of the natural nucleotides and oligopeptides is observed. Thus we can suppose the chemical evolution of complex biological compounds would take place on early stage of the star system evolution, inside the protoplanetary nebula and reached the stage of polymerization before the end of planet accretion. The compound synthesized in these conditions could have survived inside comets, the last witnesses of the formation of our Solar system. The aim of our work was also to study the in influence of mineral substrates on the reaction of oligomerization of amino acids under the action of vacuum ultraviolet (VUV) radiation with wavelengths less than 200 nm, one of the main energy sources of the Sun. Simple oligopeptides can be formed on solid material not only by VUV-light but also by proton radiation, heat, and gamma-radiation. Thus, it can be assumed that the chemical evolution would have taken place during the early stage of the Solar system origin and reached the stage of polymerization before the end of planet accretion on the surface of small bodies.

Simakov, Michael B.; Kuzicheva, Evgenia; Gontareva, Natalia

388

Why is it necessary to establish a classification of extra-solar planets?  

NASA Astrophysics Data System (ADS)

While working with extra-solar planet databases, it is very useful to have a taxonomy scale (classification), for example, like the Harvard classification for stars. This new taxonomy has to be comprehensible and present the most relevant information about extra-solar planets. We propose an extra-solar planet taxonomy scale with five parameters. %

Plávalová, E.

2014-03-01

389

Wolbachia Bacteria Effects after Experimental Interspecific Transfers in Terrestrial Isopods  

E-print Network

Wolbachia Bacteria Effects after Experimental Interspecific Transfers in Terrestrial Isopods T of their hosts to increase in frequency in host populations. In terrestrial isopods for example, Wolba- chia in Bandi et al., 2001). In terrestrial isopods particularly, they are responsible for the feminization

390

Global response patterns of terrestrial plant species to nitrogen addition  

Microsoft Academic Search

Summary • Better understanding of the responses of terrestrial plant species under global nitrogen (N) enrichment is critical for projection of changes in structure, functioning, and service of terrestrial ecosystems.  Here, a meta-analysis of data from 304 studies was carried out to reveal the general response patterns of terrestrial plant species to the addition of N.  Across 456

Jianyang Xia; Shiqiang Wan

2008-01-01

391

Atmospheric Circulation of Terrestrial Exoplanets Adam P. Showman  

E-print Network

Atmospheric Circulation of Terrestrial Exoplanets Adam P. Showman University of Arizona Robin D of terrestrial exoplanets, and discuss the interaction of their circulation with the hydrological cycle and global-scale climate feedbacks. Terrestrial exoplanets occupy a wide range of physical and dynamical

392

Terrestrial manganese-53 --A new monitor of Earth surface processes  

E-print Network

Terrestrial manganese-53 -- A new monitor of Earth surface processes Joerg M. Schaefer a,, Thomas of the terrestrial cosmogenic radionuclide manganese-53 (T1/2 =3.7 Ma) measured in thirteen samples from nine dolerite surfaces in the Dry Valleys, Antarctica. The terrestrial manganese-53 concentrations correlate

Winckler, Gisela

393

Terrestrial forest management plan for Palmyra Atoll  

USGS Publications Warehouse

This 'Terrestrial Forest Management Plan for Palmyra Atoll' was developed by the U.S. Geological Survey (USGS) for The Nature Conservancy (TNC) Palmyra Program to refine and expand goals and objectives developed through the Conservation Action Plan process. It is one in a series of adaptive management plans designed to achieve TNC's mission toward the protection and enhancement of native wildlife and habitat. The 'Terrestrial Forest Management Plan for Palmyra Atoll' focuses on ecosystem integrity and specifically identifies and addresses issues related to assessing the status and distribution of resources, as well as the pressures acting upon them, most specifically nonnative and potentially invasive species. The plan, which presents strategies for increasing ecosystem integrity, provides a framework to implement and track the progress of conservation and restoration goals related to terrestrial resources on Palmyra Atoll. The report in its present form is intended to be an overview of what is known about historical and current forest resources; it is not an exhaustive review of all available literature relevant to forest management but an attempt to assemble as much information specific to Palmyra Atoll as possible. Palmyra Atoll is one of the Northern Line Islands in the Pacific Ocean southwest of the Hawai`ian Islands. It consists of many heavily vegetated islets arranged in a horseshoe pattern around four lagoons and surrounded by a coral reef. The terrestrial ecosystem consists of three primary native vegetation types: Pisonia grandis forest, coastal strand forest, and grassland. Among these vegetation types, the health and extent of Pisonia grandis forest is of particular concern. Overall, the three vegetation types support 25 native plant species (two of which may be extirpated), 14 species of sea birds, six shore birds, at least one native reptile, at least seven native insects, and six native land crabs. Green and hawksbill turtles forage at Palmyra Atoll, and though rarely documented, beach nesting could be affected by terrestrial management actions. There are various nonnative or invasive species throughout the terrestrial ecosystem. The most notable examples of terrestrial invasive species include coconut palms (Cocos nucifera) and black rats (Rattus rattus). Although it is unclear whether they are nonnative, coconut palms are currently the most dominant plant across Palmyra Atoll. They compete with native plant species for space and resources and are potentially detrimental to sea birds dependent on native vegetation for roosting and nesting habitat. This competition in turn impacts nutrient resource availability, thereby reshaping energy flow in the ecosystem. Black rats are known to prey on ground-nesting sea birds and are likely responsible for the lack of burrowing sea bird reproduction at Palmyra Atoll. In addition, they may be facilitating the invasion of other nonnative species and negatively impacting other native fauna. Although the extent and impacts of these and other nonnative and (or) invasive species are not fully understood, the extent and impacts are clearly a threat to the native species and one of the most urgent threats to the overall ecosystem integrity of Palmyra Atoll. This 'Terrestrial Forest Management Plan for Palmyra Atoll' addresses issues related to invasive species and other problems. Priority goals are established as are associated objectives and strategies. The overarching goal is to perpetuate and where possible restore terrestrial ecosystem integrity through the following techniques: 1. Habitat management: Maintain and enhance habitat to the extent possible to sustain thriving Pisonia grandis forest, coastal strand forest, endemic grassland, self-sustaining populations of sea birds, shore birds, coconut crabs, native lizards, and native insects. 2. Monitoring and assessment: Acquire information on distribution and abundance as needed for conservation of each resour

Hathaway, Stacie A.; McEachern, Kathryn; Fisher, Robert N.

2011-01-01

394

Body Image  

NSDL National Science Digital Library

Whether you feel flabby or fit depends on your brain as well as your waistline. This according to neurologist Henrik Ehrsson and his colleagues at University College, London. They stimulated the nerves in volunteers' bodies in a way that tricked them into feeling like their waistlines were shrinking. The illusion activated a part of the subjects' brains called the posterior parietal cortex, which integrates sensory signals from all over the body. The nerve stimulation for each person was the same, yet some experienced the shrinking sensation more strongly--and they had more activity in this part of the brain. That suggests that two people who have identical bodies might experience their body image differently. This may lead to a better understanding of anorexia and other body-image disorders. This Science Update also contains in text format details of the research, which leads to these findings presented in the Science Update podcast. It also offers links to the other podcasts topics and resources for further inquiry.

American Association for the Advancement of Science (;)

2006-01-02

395

Bodie, CA  

NSDL National Science Digital Library

Held in a state of arrested decay, the ghost town of Bodie, California is one of the best known ghost towns in the United States. As with many a small town in the western part of the country, the town was part of the boom and bust cycle that was emblematic of the raucous world of mineral extraction, and as the gold in the region came and went, so did most of the residents of Bodie. This whole cycle began for Bodie in 1859, when a substantial quartz ledge was located in the region, along with significant deposits of gold. In 1962, the state of California took over what remained of the town in order to create a state historic park, and today approximately 200 structures remain on the site. At the website, visitors can take a photographic tour throughout many of these buildings (with some lovely interior photos as well), peruse a timeline of the townâÂÂs fortunes, and take a virtual tour of the Bodie cemetery. For persons interested in visiting Bodie, there is some helpful tips on nearby amenities and services.

396

Oligarchic and giant impact growth of terrestrial planets in the presence of gas giant planet migration  

E-print Network

We present the results of N--body simulations which examine the effect that gas giant planet migration has on the formation of terrestrial planets. The models incorporate a 0.5 Jupiter mass planet undergoing type II migration through an inner protoplanet--planetesimal disk, with gas drag included. Each model is initiated with the inner disk being at successively increased levels of maturity, so that it is undergoing either oligarchic or giant impact style growth as the gas giant migrates. In all cases, a large fraction of the disk mass survives the passage of the giant, either by accreting into massive terrestrial planets shepherded inward of the giant, or by being scattered into external orbits. Shepherding is favored in younger disks where there is strong dynamical friction from planetesimals and gas drag is more influential, whereas scattering dominates in more mature disks where dissipation is weaker. In each scenario, sufficient mass is scattered outward to provide for the eventual accretion of a set of terrestrial planets in external orbits, including within the system's habitable zone. An interesting result is the generation of massive, short period, terrestrial planets from compacted material pushed ahead of the giant. These planets are reminiscent of the short period Neptune mass planets discovered recently, suggesting that such `hot Neptunes' could form locally as a by-product of giant planet migration.

Martyn J. Fogg; Richard P. Nelson

2005-07-07

397

Linkages between terrestrial ecosystems and the atmosphere  

NASA Technical Reports Server (NTRS)

The primary research issue in understanding the role of terrestrial ecosystems in global change is analyzing the coupling between processes with vastly differing rates of change, from photosynthesis to community change. Representing this coupling in models is the central challenge to modeling the terrestrial biosphere as part of the earth system. Terrestrial ecosystems participate in climate and in the biogeochemical cycles on several temporal scales. Some of the carbon fixed by photosynthesis is incorporated into plant tissue and is delayed from returning to the atmosphere until it is oxidized by decomposition or fire. This slower (i.e., days to months) carbon loop through the terrestrial component of the carbon cycle, which is matched by cycles of nutrients required by plants and decomposers, affects the increasing trend in atmospheric CO2 concentration and imposes a seasonal cycle on that trend. Moreover, this cycle includes key controls over biogenic trace gas production. The structure of terrestrial ecosystems, which responds on even longer time scales (annual to century), is the integrated response to the biogeochemical and environmental constraints that develop over the intermediate time scale. The loop is closed back to the climate system since it is the structure of ecosystems, including species composition, that sets the terrestrial boundary condition in the climate system through modification of surface roughness, albedo, and, to a great extent, latent heat exchange. These separate temporal scales contain explicit feedback loops which may modify ecosystem dynamics and linkages between ecosystems and the atmosphere. The long-term change in climate, resulting from increased atmospheric concentrations of greenhouse gases (e.g., CO2, CH4, and nitrous oxide (N2O)) will further modify the global environment and potentially induce further ecosystem change. Modeling these interactions requires coupling successional models to biogeochemical models to physiological models that describe the exchange of water, energy, and biogenic trace gases between the vegetation and the atmosphere at fine time scales. There does not appear to be any obvious way to allow direct reciprocal coupling of atmospheric general circulation models (GCM's), which inherently run with fine time steps, to ecosystem or successional models, which have coarse temporal resolution, without the interposition of physiological canopy models. This is equally true for biogeochemical models of the exchange of carbon dioxide and trace gases. This coupling across time scales is nontrivial and sets the focus for the modeling strategy.

Bretherton, Francis; Dickinson, Robert E.; Fung, Inez; Moore, Berrien, III; Prather, Michael; Running, Steven W.; Tiessen, Holm

1992-01-01

398

Planetary System Evolution in the Terrestrial Zone  

NASA Astrophysics Data System (ADS)

We propose to characterize the role of major collisional episodes in the terrestrial zones of other planetary systems, using data from WISE (and Spitzer). We will: 1.) identify old stars whose terrestrial zones have recently been shaken up dynamically (e.g., activity similar to the Late Heavy Bombardment); and 2.) look for young stars where major collisions are occurring, signaling a phase analogous to the one when our Moon was formed. These two phases represent critical periods in the evolution of the Solar System. The Late Heavy Bombardment resulted from a destabilization of the Solar System by a mean-motion resonance between Jupiter and Saturn, leading to ejection of most of the planetesimals and an intense period of impacts onto the terrestrial planets. The formation of the Moon occurred in a younger violent phase, extending roughly from 30 to 130 Myr, when dynamical models predict that giant impacts will still occur even though most of the terrestrial planet formation is complete. Both of these phases would have produced copious dust in the terrestrial zone. Similar activity around other stars is detectable through the mid-infrared excesses emitted by such dust when it is warmed by the star (creating warm debris disks). However, previous infrared surveys have lacked the sensitivity, accuracy, or sky coverage to study this process systematically. For the first time, the WISE all-sky survey at 22 microns combines: 1.) a sufficiently large number of stars that these rare events should be seen in reasonable numbers; and 2.) mid-infrared photometry with sufficient accuracy to detect the excesses, even to within < 10% of the stellar photospheres. After extracting candidates from the WISE data, we will weed out false positives due to chance superpositions of sources or stellar mass loss. This will require acquiring ancillary data through a combination of information from the literature and new targeted observations using groundbased facilities. We will determine ages for the stars that survive this screening, using indicators such as chromospheric activity, spectral type (giant vs. main sequence), and position on a metallicity-adjusted HR diagram. The result will be a listing of stars with well-estimated ages and accurately- measured excesses signaling likely violent collisional episodes, providing a broad perspective on the frequency and intensity of the violent phases of planetary system evolution. We will put this work into context by comparison with the results of our theoretical models of debris disk collisional cascades and evolution. Our proposed work will allow comparison of critical events in the evolution of the Solar System and the Earth with the evolution of other planetary systems in their terrestrial zones.

Rieke, George

399

Outward migration of terrestrial embryos in binary systems  

NASA Astrophysics Data System (ADS)

We consider the formation and migration of protoplanetary embryos in discs around the stars in tight binary systems (separations of ~20au). In such systems, the initial stages of runaway embryo formation are expected to only take place within some critical disc radius acrit, due to the perturbing effect of the binary companions. We perform N-body simulations of the evolution of such a population of inner-disc embryos surrounded by an outer disc of smaller planetesimals. Taking Alpha Centauri-B as our fiducial reference example in which acrit ~ 0.7au, and using a Minimum Mass Nebular Model with ? ~ a-3/2, we find that within 106yr (107yr), systems will on average contain embryos which have migrated out to 0.9au (1.2au), with the average outermost body having a mass of 0.2M?(0.4M?). Changes to increase the surface density of solids or to use a flatter profile both produce increased embryo migration and growth. At a given time, the relative change in the semimajor axis of the outermost embryo in these simulations is found to be essentially independent of acrit, and we note that little further embryo migration takes place beyond 107yr. We conclude that the suppression of runaway growth outside acrit does not mean that the habitable zones in such tight binary systems will be devoid of detectable, terrestrial mass planets, even if acrit lies significantly interior to the inner edge of the habitable zone.

Payne, Matthew J.; Wyatt, Mark C.; Thébault, Philippe

2009-12-01

400

Phenotypic population divergence in terrestrial vertebrates at macro scales.  

PubMed

Phenotypic divergence between populations, i.e. how much phenotypes within a species vary geographically, is critical to many aspects of ecology and evolution, including eco-geographical trends, speciation and coexistence. Yet, the variation of divergence across species with different ecologies and distributions and the relative role of adaptive causes remains little understood. We predict that genetic control vs. phenotypic plasticity of traits, geographical distance and (assuming adaptation) environmental differences should explain much of the phenotypic variability between populations. We tested these predictions with body sizes of 1447 populations in 98 terrestrial vertebrate species. Population phenotypic variability differs strongly across species, and divergence increases with increasing levels of clade-typical phenotypic plasticity, the area covered by populations and body size. Geographical distance and environmental dissimilarity are similarly important predictors of divergence within species, highlighting a potential role for biotic and environmental conditions. Increased availability of phylogeographical and ecological data should facilitate further understanding of population divergence drivers at broad scales. PMID:19708969

Jetz, Walter; Ashton, Kyle G; La Sorte, Frank A

2009-11-01

401

Body Imaging  

NASA Technical Reports Server (NTRS)

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.

2001-01-01

402

Body Imaging  

NASA Technical Reports Server (NTRS)

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.

2001-01-01

403

Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica 29 Ecological Biogeography of theTerrestrial  

E-print Network

and Convey 2007). However, terrestrial ecosystems of Antarctica are not immune to global changes (Adams et alEcological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica 29 Ecological Biogeography of theTerrestrial Nematodes ofVictoria Land,Antarctica Byron J. Adams1 , Diana H. Wall2 , Ross A

Wall, Diana

404

Body parts  

NASA Astrophysics Data System (ADS)

In this project, the artist wishes to examine corporeality in the virtual realm, through the usage of the (non)-physical body of the avatar. An art installation created in the virtual world of Second Life, which is meant to be accessed with site specific avatars, will provide the creative platform whereby this investigation is undertaken. Thus, "body parts" seeks to challenge the residents of virtual environments into connecting with the virtual manifestations, i.e., avatars of others in an emotionally expressive/intimate manner.

Ayiter, Elif

2010-01-01

405

Body Imaging  

NASA Technical Reports Server (NTRS)

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.

1990-01-01

406

Three extra mirror or sequential families: case for a heavy Higgs boson and inert doublet.  

PubMed

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(Z). PMID:21668143

Martínez, Homero; Melfo, Alejandra; Nesti, Fabrizio; Senjanovi?, Goran

2011-05-13

407

Detection of Terrestrial Planets Using Transit Photometry  

NASA Technical Reports Server (NTRS)

Transit photometry detection of planets offers many advantages: an ability to detect terrestrial size planets, direct determination of the planet's size, applicability to all main-sequence stars, and a differential brightness change of the periodic signature being independent of stellar distance or planetary orbital semi-major axis. Ground and space based photometry have already been successful in detecting transits of the giant planet HD209458b. However, photometry 100 times better is required to detect terrestrial planets. We present results of laboratory measurements of an end-to-end photometric system incorporating all of the important confounding noise features of both the sky and a space based photometer including spacecraft jitter. In addition to demonstrating an instrumental noise of less than 10 ppm (an Earth transit of a solar-like star is 80 ppm), the brightnesses of individual stars were dimmed to simulate Earth-size transit signals. These 'transits' were reliably detected as part of the tests.

Koch, David; Witteborn, Fred; Jenkins, Jon; Dunham, Edward; Boruci, William; DeVincenzi, Donald (Technical Monitor)

2001-01-01

408

Terrestrial-passage theory: failing a test.  

PubMed

Terrestrial-passage theory proposes that the 'moon' and 'sky' illusions occur because observers learn to expect an elevation-dependent transformation of visual angle. The transformation accompanies daily movement through ordinary environments of fixed-altitude objects. Celestial objects display the same visual angle at all elevations, and hence are necessarily non-conforming with the ordinary transformation. On hypothesis, observers should target angular sizes to appear greater at elevation than at horizon. However, in a sample of forty-eight observers there was no significant difference between the perceived angular size of a constellation of stars at horizon and that predicted for a specific elevation. Occurrence of the illusion was not restricted to those observers who expected angular expansion. These findings fail to support the terrestrial-passage theory of the illusion. PMID:19662949

Reed, Charles F; Krupinski, Elizabeth A

2009-01-01

409

The precambrian evolution of terrestrial life.  

NASA Astrophysics Data System (ADS)

The early appearance of life on Earth suggests that under appropriate environmental conditions the probability of chemical evolution proceeding to the point of biogenesis may be reasonably high. Most of biological history has been the history of microorganisms, with tissue-grade plants and animals characterizing only the most recent 15% or so of the fossil record. Intelligent life has occupied only the latest instant in geological time. The time table of terrestrial evolution is governed more by the particulars of our planet's physical and biological history than by some universal tempo of evolutionary change. One aspect of terrestrial life that is likely to be universal is the organization of populations into efficient biogeochemical systems.

Knoll, A. H.

410

Building Blocks of the Terrestrial Planets: Mineralogy of Hungaria Asteroids  

NASA Astrophysics Data System (ADS)

Deciphering the mineralogy of the Hungaria asteroids has the potential to place constraints on the material from which the terrestrial planets accreted. Among asteroids with semi-major axes interior to the main-belt (e.g., Hungarias, Mars-crossers, and near-Earth asteroids), only the Hungarias are located in relatively stable orbital space. Hungaria asteroids have likely resided in this orbital space since the planets completed their migration to their current orbits. The accretion and igneous differentiation of primitive asteroids appears to be a function of chronology and heliocentric distance. However, differentiated bodies that originated in the terrestrial planet region were either accreted or scattered out of this region early in solar system history. Thus, the Hungaria asteroids represent the closest reservoir of in situ material to the terrestrial planet region from early in solar system history. We present VISNIR 0.45-2.45 µm) and NIR spectra 0.65-2.45 µm) spectra of 24 Hungaria group (objects in similar orbital space) asteroids. Our NIR data (17 objects) were acquired using the InfraRed Telescope Facility and was supplemented with available visible data. Spectra of seven objects were obtained from the MIT-UH-IRTF survey. We distinguish our sample between Hungaria family (presumed fragments of parent 434 Hungaria; 2 objects) and Hungaria background (group minus family 22 objects) asteroids using proper orbital elements. The classification of each asteroid is determined using the taxonomy of Bus-DeMeo. We find that S- and S-subtypes are prevalent among the Hungaria background population (17/22). Spectral band parameters measurements (i.e., Band I and Band II centers and depths, and Band Area Ratio) indicate that eight of these S-types are analogous with undifferentiated ordinary chondrites (SIV “boot” of S-subtypes plot). Mafic silicate mineral abundances and compositions derived for these SIV asteroids mainly correlate with L chondrites. However, one object is an SIII subtype (possible ureilite analog), while two asteroids are SVI subtypes (possible primitive achondrite analog). Family member 6447 Terrycole is a Xe-type, consistent with the taxonomic classification of the parent 434 Hungaria.

Lucas, Michael; Emery, J. P.

2013-10-01

411

Solar Terrestrial Observatory Space Station Workshop Report  

NASA Technical Reports Server (NTRS)

In response to a need to develop and document requirements of the Solar Terrestrial Observatory at an early time, a mini-workshop was organized and held on June 6, 1985. The participants at this workshop set as their goal the preliminary definition of the following areas: (1) instrument descriptions; (2) placement of instrumentation on the IOC Space Station; (3) servicing and repair assessment; and (4) operational scenarios. This report provides a synopsis of the results of that workshop.

Roberts, W. T. (editor)

1986-01-01

412

Guiding future research on terrestrial ecosystem disturbance  

NASA Astrophysics Data System (ADS)

With North American ecosystems responsible for drawing hundreds of teragrams of carbon from the atmosphere each year, the tenuous balance of the terrestrial carbon budget can be upset for decades by disturbances such as fires, storms, disease outbreaks, insect infestations, and logging. Research cataloging the effects of such disturbances on regional carbon cycling tends to be sporadic or of limited scope. Most research has focused on forests but is less extensive for other important ecosystems such as grasslands or permafrost peatlands.

Schultz, Colin

2013-04-01

413

WATER VAPOUR ABSORPTION IN TERRESTRIAL ISOPODS  

Microsoft Academic Search

Summary Continuous and intermittent gravimetric measurements have identified active water vapour absorption (WVA) in three species of terrestrial Isopoda. Water activity thresholds for uptake lie in the range 0.92-0.95. Above the threshold, WVA shows non-saturated kinetics; the rectum apparently serves as a supplemen- tary avenue for fluid resorption during rapid uptake. Standardized uptake fluxes, corrected for vapour pressure deficit, can

JONATHAN C. WRIGHT; JOHN MACHIN

1990-01-01

414

Terrestrial contamination in Apollo lunar samples.  

NASA Technical Reports Server (NTRS)

The contamination prevention procedures adopted for controlling the collection, processing, and analysis of the Apollo lunar samples in order to keep them free of significant levels of terrestrial organic matter are described. The organic contaminants actually found in the samples by the various investigators are summarized. It is shown that the program succeeded in providing investigators with samples containing less than 0.1 ppm total contamination.

Flory, D. A.; Simoneit, B. R.

1972-01-01

415

The Nitrogen Cycle in Terrestrial Ecosystems  

Microsoft Academic Search

The terrestrial nitrogen (N) cycle comprises soil, plant and animal pools that contain relatively small quantities of biologically\\u000a active N, in comparison to the large pools of relatively inert N in the lithosphere and atmosphere, but that nevertheless\\u000a exert a substantial influence on the dynamics of the global biogeochemical N cycle. After carbon (ca. 400 g kg?1) and oxygen (ca.

Ann McNeill; Murray Unkovich

416

Physiology of exolaccase production by Thelephora terrestris  

Microsoft Academic Search

Thelephora terrestris, an ectomycorrhizal hymenomycete, produces extracellular laccase when grown in minimal liquid medium. The enzyme was characterized as a protein of 66 kDa. The optimal pH varied depending on the substrate utilized, being 5.0 for syringaldazine, 4.8 for guaiacol and 3.4 for ABTS. The Km was 2.52±0.4 ?M for syringaldazine, 16±1.9 ?M for ABTS and 120.6±4.9 ?M for guaiacol.

Carla C Kanunfre; Glaci T Zancan

1998-01-01

417

Alarm pheromone in the earthworm Lumbricus terrestris.  

PubMed

Noxious stimulation of the earthworm Lumbricus terrestris elicits secretion of a mucus that is aversive to other members of the species, as well as to the stimulated animal when it is encountered later. This alarm pheromone is not readily soluble in water and retains its aversive properties for at least several months if not disturbed. Its influence may be responsible for some features of the data on instrumental learning in earthworms. PMID:5663305

Ressler, R H; Cialdini, R B; Ghoca, M L; Kleist, S M

1968-08-01

418

Observed beaming of terrestrial myriametric radiation  

NASA Technical Reports Server (NTRS)

Observations by the Dynamics Explorer 1 satellite are discussed which validate the theory that terrestrial myriametric radiation (TMR) is produced by the linear conversion of electrostatic upper hybrid waves to electromagnetic radiation via a radio window. A remote sensing technique based on the theory is used to investigate the location and characteristics of the source region. Finally, the location of the TMR source region is demonstrated by direct measurement.

Jones, Dyfrig; Calvert, W.; Gurnett, D. A.; Huff, R. L.

1987-01-01

419

Testbed for Satellite and Terrestrial Interoperability (TSTI)  

NASA Technical Reports Server (NTRS)

Various issues associated with the "Testbed for Satellite and Terrestrial Interoperability (TSTI)" are presented in viewgraph form. Specific topics include: 1) General and specific scientific technical objectives; 2) ACTS experiment No. 118: 622 Mbps network tests between ATDNet and MAGIC via ACTS; 3) ATDNet SONET/ATM gigabit network; 4) Testbed infrastructure, collaborations and end sites in TSTI based evaluations; 5) the Trans-Pacific digital library experiment; and 6) ESDCD on-going network projects.

Gary, J. Patrick

1998-01-01

420

Comparison Charts of Geological Processes: Terrestrial Planets  

NSDL National Science Digital Library

This chart presents information on the geological processes (volcanism, impact cratering, tectonics, and gradation) that have affected the Earth, Moon, and the terrestrial planets. Students compare the effects these processes have had on the Moon and planets. There is also a blank chart and a sheet of notes on the geological processes that may be used in conjunction with this chart. This chart is one of the activities for the Exploring Planets in the Classroom's Introduction to the Solar System.

421

Emerging Technological Needs for Terrestrial Biogeochemistry Measurements  

NASA Astrophysics Data System (ADS)

With the Earth's climate, flora, and fauna undergoing rapid change, understanding terrestrial ecosystem processes and their sensitivity to environmental and biotic conditions has become paramount. Many theories and models remain rudimentary due to sensor and environmental data inadequacies that persist despite rapid developments in sensor, computing, and networking technologies. This situation has prompted researchers to focus on the development of novel sensors to vastly improve our capability of capturing the high spatial and temporal variations within biogeochemical processes.

Hamada, Yuki; Graham, Robin L.; Matamala, Roser

2013-12-01

422

Lunar and Planetary Science XXXV: Terrestrial Planets  

NASA Technical Reports Server (NTRS)

The session "Terrestrial Planets: included:Lunar Soils May Tell Us When the Geomagnetic Field First Appeared; Metal-Silicate Segregation in Deforming Dunitic Rocks: Applications to Core Formation in Europa and Ganymede; Diamond Formation in Core Segregation Experiments; The Effect of Pressure on Potassium Partitioning Between Metallic Liquid and Silicate Melt; Reduction of W, Mn, and Fe, During High-Temperature Vaporization; Micrometeoritic Neon in the Earth s Mantle ; and New Analyses of Diverse Hadean Zircon Inclusions from Jack Hills.

2004-01-01

423

Body Circulation  

NSDL National Science Digital Library

Students are introduced to the circulatory system, the heart, and blood flow in the human body. Through guided pre-reading, during-reading and post-reading activities, students learn about the circulatory system's parts, functions and disorders, as well as engineering medical solutions. By cultivating literacy practices as presented in this lesson, students can improve their scientific and technological literacy.

Integrated Teaching And Learning Program

424

Terrestrial water fluxes dominated by transpiration.  

PubMed

Renewable fresh water over continents has input from precipitation and losses to the atmosphere through evaporation and transpiration. Global-scale estimates of transpiration from climate models are poorly constrained owing to large uncertainties in stomatal conductance and the lack of catchment-scale measurements required for model calibration, resulting in a range of predictions spanning 20 to 65 per cent of total terrestrial evapotranspiration (14,000 to 41,000 km(3) per year) (refs 1, 2, 3, 4, 5). Here we use the distinct isotope effects of transpiration and evaporation to show that transpiration is by far the largest water flux from Earth's continents, representing 80 to 90 per cent of terrestrial evapotranspiration. On the basis of our analysis of a global data set of large lakes and rivers, we conclude that transpiration recycles 62,000 ± 8,000 km(3) of water per year to the atmosphere, using half of all solar energy absorbed by land surfaces in the process. We also calculate CO2 uptake by terrestrial vegetation by connecting transpiration losses to carbon assimilation using water-use efficiency ratios of plants, and show the global gross primary productivity to be 129 ± 32 gigatonnes of carbon per year, which agrees, within the uncertainty, with previous estimates. The dominance of transpiration water fluxes in continental evapotranspiration suggests that, from the point of view of water resource forecasting, climate model development should prioritize improvements in simulations of biological fluxes rather than physical (evaporation) fluxes. PMID:23552893

Jasechko, Scott; Sharp, Zachary D; Gibson, John J; Birks, S Jean; Yi, Yi; Fawcett, Peter J

2013-04-18

425

Subthalamic nucleus influences spatial orientation in extra-personal space.  

PubMed

While the role of frontal and parietal cortex in spatial orientation has been studied extensively, the contribution of the basal ganglia and especially the subthalamic nucleus to spatial orientation remains less clear. Here we use subthalamic nucleus (STN) deep brain stimulation (DBS) in Parkinson's disease (PD) as a reversible model of functional lesioning to evaluate the influence of the STN in extra-personal space orientation. To this end, 12 PD patients were examined 1 year after implantation of DBS electrodes in the STN after overnight withdrawal of L-dopa. Patients were tested in a pseudo-randomized order while both stimulators, the right only, the left only, or no stimulator, were switched on. Patients performed line bisection and a reaction time task responding to stimuli of the middle, the left, and the right extra-personal space. A separate assessment of the right and left hand responding to visual stimuli in each hemispace made it possible to distinguish hemi-spatial and hemi-motor impairments. No asymmetries in space orientation were found when both stimulators were switched OFF, when both stimulators were switched ON, and when only the right stimulator was switched ON. When only the left subthalamic stimulation was switched ON, the reaction times of both hands to visual stimuli in the left extra-personal hemispace increased significantly and the line bisection test showed a significant orientation to the right. These results lead to the conclusion that the STN and its cortical projections influence the network involved in visuospatial orientation. These patterns of symptoms of neglect demonstrate the influence of the STN on the attentional system of the nondominant hemisphere. PMID:16211596

Witt, Karsten; Kopper, Florian; Deuschl, Günther; Krack, Paul

2006-03-01

426

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

PubMed

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

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

2006-07-01

427

Search for Universal Extra Dimensions in pp¯ Collisions  

NASA Astrophysics Data System (ADS)

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 7.3fb-1, collected by the D0 detector at a pp¯ 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-1>260GeV in a minimal UED model.

Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Aoki, M.; Askew, A.; Åsman, B.; Atkins, S.; Atramentov, O.; Augsten, K.; Avila, C.; BackusMayes, J.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Belanger-Champagne, C.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brandt, O.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Brown, J.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burnett, T. H.; Buszello, C. P.; Calpas, B.; Camacho-Pérez, E.; Carrasco-Lizarraga, M. A.; Casey, B. C. K.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Chevalier-Théry, S.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Croc, A.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dorland, T.; Dubey, A.; Dudko, L. V.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garcia-Bellido, A.; García-Guerra, G. A.; Gavrilov, V.; Gay, P.; Geng, W.; Gerbaudo, D.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Goryachev, V. N.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hagopian, S.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jamin, D.; Jayasinghe, A.; Jesik, R.; Johns, K.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kaadze, K.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kulikov, S.; Kumar, A.; Kupco, A.; Kur?a, T.; Kuzmin, V. A.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lellouch, J.; Li, H.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Lubatti, H. J.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Mansour, J.; Maravin, Y.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Muanza, G. S.; Mulhearn, M.; Nagy, E.; Naimuddin, M.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Novaes, S. F.; Nunnemann, T.; Obrant, G.; Orduna, J.; Osman, N.; Osta, J.; Otero y Garzón, G. J.; Padilla, M.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Piegaia, R.; Pleier, M.-A.; Podesta-Lerma, P. L. M.; Podstavkov, V. M.; Polozov, P.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Rangel, M. S.; Ranjan, K.; Ratoff, P. N.; Razumov, I.; Renkel, P.; Rijssenbeek, M.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Safronov, G.; Sajot, G.; Salcido, P.; Sánchez-Hernández, A.; Sanders, M. P.; Sanghi, B.; Santos, A. S.; Savage, G.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schliephake, T.; Schlobohm, S.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shchukin, A. A.; Shivpuri, R. K.; Simak, V.; Sirotenko, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Smith, K. J.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.

2012-03-01

428

Supersymmetry Breaking, Extra Dimensions and Neutralino Dark Matter  

E-print Network

We show some phenomenological implications for the dark matter problem of a class of models with deflected anomaly mediated supersymmetry breaking in the context of the MSSM. This scenario can be naturally embedded in a brane world model with one compactified extra dimension. It turns out that in these models the neutralino is still the LSP and so a good candidate as cold dark matter. We found that the neutralino is quite a pure bino in almost all the parameter space. Moreover we computed the thermal relic density and we found wide cosmologically allowed regions for the neutralino.

Andrea M. Lionetto

2005-09-13

429

Efficacious extra U(1) factor for the supersymmetric standard model  

NASA Astrophysics Data System (ADS)

The totality of neutrino-oscillation phenomena appears to require the existence of a light singlet neutrino. As pointed out recently, this can be naturally accommodated with a specific extra U(1) factor contained in the superstring-inspired E6 model and its implied particle spectrum. We analyze this model for other possible consequences. We discuss specifically the oblique corrections from Z-Z' mixing, the phenomenology of the two-Higgs-doublet sector, and the associated neutralino sector, as well as possible scenarios of gauge-coupling unification.

Keith, E.; Ma, Ernest

1996-09-01

430

NRQCD results on the MILC extra coarse ensemble  

E-print Network

We present preliminary results using NRQCD to describe heavy quarks on the MILC 2+1 flavour dynamical extra coarse ensemble. We calculate the spectra of low lying states in bottomonium to complement earlier results on the finer MILC ensembles. We then exploit the coarseness of the lattices to calculate charm propagators using NRQCD. These are used to examine the charmonium spectrum and to calclate the mass of the $B_c$ using NRQCD. Finally we look breifly at the $B_d$ and $B_s$ systems using the imporoved staggered formalism to describe the light valence quarks.

I. F. Allison; C. T. H. Davies; A. Gray

2005-09-30

431

The size of compact extra dimensions from blackbody radiation laws  

NASA Astrophysics Data System (ADS)

In this work we generalize the Stefan-Boltzmann and Wien’s displacement laws for a D-dimensional manifold composed by 4 non-compact dimensions and D-4 compact dimensions, R×T. The electromagnetic field is assumed to pervade all compact and non-compact dimensions. In particular, the total radiated power becomes R(T)=?BT4+?D(a) TD, where a is the size of the compact extra dimensions. For D=10, predicted from String Theory, and D=11, from M-Theory, the outcomes agree with available experimental data for a as high as 2?10-7m.

Ramos, Ramaton; Boschi-Filho, Henrique

2014-01-01

432

Constraints on split universal extra dimensions from electroweak precision tests  

NASA Astrophysics Data System (ADS)

We present strongly improved electroweak precision constraints on the split-UED (universal extra dimension) model. We find that the dominating effect arises from contributions to the muon decay rate by the exchange of even-numbered W boson Kaluza-Klein modes at tree level, which so far have not been discussed in the context of UED models. The constraints on the split-UED parameter space are translated into bounds on the mass difference of the first Kaluza-Klein mode of fermions and the lightest Kaluza-Klein mode, which will be tested at the LHC.

Flacke, Thomas; Pasold, Christian

2012-06-01

433

Search for large extra dimensions in dielectron and diphoton production  

E-print Network

.1156 P The possibility that the universe has more than three spa- tial dimensions has long been discussed [1]. Recent devel- opments in string theory suggest that there could be up to seven additional spatial dimensions, compactified at very small... distances, on the order of 10 232 m. In a new model [2], possibly realizable within string theory [3], several of the compactified extra dimensions (ED) are suggested to be as large as 1 mm. These large ED are introduced to solve the hierarchy problem...

Baringer, Philip S.; Bean, Alice; Coppage, Don; Hebert, C.

2001-02-01

434

Inert scalar dark matter in an extra dimension inspired model  

NASA Astrophysics Data System (ADS)

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.

Lineros, R. A.; Pereira dos Santos, F. A.

2014-10-01

435

APOLLO 9: Dave scott performs Extra Vehicular Activities  

NASA Technical Reports Server (NTRS)

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.

1974-01-01

436

Neutron-antineutron oscillations in a warped extra dimension  

SciTech Connect

We investigate neutron-antineutron oscillations in the Randall-Sundrum warped extra dimensional scenario. The four dimensional effective strengths of the relevant operators that induce the oscillations are calculated up to an arbitrary coupling along with their corresponding enhancements due to QCD 1-loop running effects. We find that the {Delta}B=2 operators can be geometrically suppressed without fine tuning to within current experimental limits with a warped down four dimensional mass scale which can be as low as a fraction of a TeV.

Winslow, Peter T.; Ng, John N. [Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, V6T 1Z1 (Canada); Theory Group, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (Canada)

2010-05-15

437

Gauge and Higgs Boson Masses from an Extra Dimension  

E-print Network

We present novel calculations of the mass hierarchy of the $SU(2)$ pure gauge theory on a space-time lattice with an orbifolded fifth dimension. This theory has three parameters; the gauge coupling $\\beta$, the anisotropy $\\gamma$, which is a measure of the ratio of the lattice spacing in the four dimensions to that in the fifth dimension, and the extent of the extra dimension $N_{5}$. Using a large basis of scalar and vector operators we explore in detail the spectrum along the $\\gamma = 1$ line, and for the first time we investigate the spectrum for $\\gamma \

Moir, Graham; Irges, Nikos; Knechtli, Francesco; Yoneyama, Kyoko

2014-01-01

438

Gauge and Higgs Boson Masses from an Extra Dimension  

E-print Network

We present novel calculations of the mass hierarchy of the $SU(2)$ pure gauge theory on a space-time lattice with an orbifolded fifth dimension. This theory has three parameters; the gauge coupling $\\beta$, the anisotropy $\\gamma$, which is a measure of the ratio of the lattice spacing in the four dimensions to that in the fifth dimension, and the extent of the extra dimension $N_{5}$. Using a large basis of scalar and vector operators we explore in detail the spectrum along the $\\gamma = 1$ line, and for the first time we investigate the spectrum for $\\gamma \

Graham Moir; Peter Dziennik; Nikos Irges; Francesco Knechtli; Kyoko Yoneyama

2014-11-03

439

A new list of extra-galactic radio jets  

E-print Network

A catalogue of extra-galactic jets is very useful both in observational and theoretical studies of active galaxies. With the use of new powerful radio instruments, the detailed structures of very compact or weak radio sources are investigated observationally and many new radio jets are detected. In this paper, we give a list of 661 radio sources with detected radio jets known to us prior to the end of December 2000. All references are collected for the observations of jets in radio, IR, optical, UV and X-ray wave-bands.

F. K. Liu; Y. H. Zhang

2002-12-20

440

Inert scalar dark matter in an extra dimension inspired model  

E-print Network

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 a 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.

R. A. Lineros; F. A. Pereira dos Santos

2014-07-22

441

On the Modeling of Electrical Effects Experienced by Space Explorers During Extra Vehicular Activities: Intracorporal Currents, Resistances, and Electric Fields  

NASA Technical Reports Server (NTRS)

Recent research has shown that space explorers engaged in Extra Vehicular Activities (EVAs) may be exposed, under certain conditions, to undesired electrical currents. This work focuses on determining whether these undesired induced electrical currents could be responsible for involuntary neuromuscular activity in the subjects, possibly caused by either large diameter peripheral nerve activation or reflex activity from cutaneous afferent stimulation. An efficient multiresolution variant of the admittance method along with a millimeter-resolution model of a male human body were used to calculate induced electric fields, resistance between contact electrodes used to simulate the potential exposure condition, and currents induced in the human body model. Results show that, under realistic exposure conditions using a 15V source, current density magnitudes and total current injected are well above previously reported startle reaction thresholds. This indicates that, under the considered conditions, the subjects could experience involuntary motor response.

Cela, Carlos J.; Loizos, Kyle; Lazzi, Gianluca; Hamilton, Douglas; Lee, Raphael C.

2011-01-01

442

Modeling of body mass index by Newton's second law  

Microsoft Academic Search

Since laws of physics exists in nature, their possible relationship to terrestrial growth is introduced. By considering the human body as a dynamic system of variable mass (and volume), growing under a gravity field, it is shown how natural laws may influence the vertical growth of humans. This approach makes sense because the non-linear percentile curves of different aspects of

Enrique Canessa; Abdus Salam

2007-01-01

443

The oxygen isotope composition of earth's oldest rocks and evidence of a terrestrial magma ocean  

NASA Astrophysics Data System (ADS)

Analysis of Hadean and Archean rocks for 16O-17O-18O isotopes demonstrates that the Terrestrial Mass Fractionation Line of oxygen isotopes has had the same slope and intercept for at least the past 4.0 and probably for as long as 4.2 Ga. The homogenization of oxygen isotopes required to produce such long-lived consistency was most easily established by mixing in a terrestrial magma ocean. The measured identical oxygen isotope mass fractionation lines for Earth and Moon suggest that oxygen isotope reservoirs of both bodies were homogenized at the same time during a giant moon-forming impact. But other sources of heat for global melting cannot be excluded such as bolide impacts during early accretion of proto-Earth, the decay of short-lived radioactive isotopes, or the energy released during segregation of core from mantle.

Rumble, D.; Bowring, S.; Iizuka, T.; Komiya, T.; Lepland, A.; Rosing, M. T.; Ueno, Y.

2013-06-01

444

Body Weight and Body Image  

PubMed Central

Health Issue Body weight is of physical and psychological importance to Canadian women; it is associated with health status, physical activity, body image, and self-esteem. Although the problems associated with overweight and obesity are indeed serious, there are also problems connected to being underweight. Weight prejudice and the dieting industry intensify body image concerns for Canadian women and can have a major negative impact on self-esteem. Key Findings Women have lower BMIs than men, a lower incidence of being overweight and a higher incidence of being underweight. However, women across all weight categories are more dissatisfied with their bodies. Sixty percent of women are inactive, and women with a BMI of 27 or higher are more likely to be inactive than women with lower BMIs. The data show that women are aware of the health benefits of exercise, but there is a gap between knowledge and practice. When asked about barriers to health improvement, 39.7% of women cited lack of time and 39.2% lack of willpower. Data Gaps and Recommendations Weight prejudice must be made unacceptable and positive body image should be encouraged and diversity valued. Health policies should encourage healthy eating and healthy activity. Health curricula for young students should include information about healthy eating, active lifestyle, and self-esteem. Physical activities that mothers can participate in with their families should be encouraged. Research should be funded to elucidate the most effective methods of getting women to become and remain physically active without focusing on appearance. PMID:15345068

Olmsted, Marion P; McFarlane, Traci

2004-01-01

445

Body Code  

NSDL National Science Digital Library

This 9-minute animation -- the joint effort of a scientific animator, a time-lapse imaging expert, and a sound artist -- takes the viewer on a wordless journey through the molecular universe of the body's cells, tissues, and organs. One scene captures the signal for a cell to divide while another takes the viewer on a roller-coaster ride through a DNA strand as it is transcribed.

Drew Berry (The Walter and Eliza Hall Institute, Melbourne, Australia;); Jeremy Pickett-Heaps (University of Melbourne;); François Tétaz (The Walter and Eliza Hall Institute, Melbourne, Australia;)

2003-01-01

446

Anomalous gauge couplings from composite Higgs and warped extra dimensions  

NASA Astrophysics Data System (ADS)

We examine trilinear and quartic anomalous gauge couplings (AGCs) generated in composite Higgs models and models with warped extra dimensions. We first revisit the SU(2) L × U(1) Y effective Lagrangian and derive the charged and two-photon neutral AGCs. We derive the general perturbative contributions to the pure field-strength operators from spin 0, , 1 resonances by means of the heat kernel method. In the composite Higgs framework, we derive the pattern of expected deviations from typical SO( N ) embeddings of the light composite top partner. We then study a generic warped extra dimension framework with AdS 5 background, recasting in few parameters the features of models relevant for AGCs. We also present a detailed study of the latest bounds from electroweak and Higgs precision observables, with and without brane kinetic terms. For vanishing brane kinetic terms, we find that the S and T parameters exclude KK gauge modes of the RS custodial [non-custodial] scenario below 7 .7 [14 .7] TeV, for a brane Higgs and below 6 .6 [8 .1] TeV for a Pseudo Nambu-Goldstone Higgs, at 95% CL. These constraints can be relaxed in presence of brane kinetic terms. The leading AGCs are probing the KK gravitons and the KK modes of bulk gauge fields in parts of the parameter space. In these scenarios, the future CMS and ATLAS forward proton detectors could be sensitive to the effect of KK gravitons in the multi-TeV mass range.

Fichet, Sylvain; von Gersdorff, Gero

2014-03-01

447

Cosmological magnetogenesis from extra-dimensional Gauss-Bonnet gravity  

NASA Astrophysics Data System (ADS)

Generation of primordial magnetic fields during inflation typically requires the breaking of conformal invariance of the electromagnetic action. In this paper this has been achieved naturally in a higher-dimensional cosmological model with a Gauss-Bonnet term in the action. The evolution of the scale factor of the extra dimension (whose dynamics is influenced by the Gauss-Bonnet term) acts as the cause for the breaking of conformal invariance. Different cases have been investigated, each of which is characterized by the number of higher dimensions, the value of the Gauss-Bonnet parameter, and the cosmological constant. Many of the scenarios considered are highly constrained by the requirements that the cosmic evolution is stable, that the normal dimensions expand, and that there is no backreaction due to growing electric fields. However, there do exist scenarios which satisfy the above requirements and are well suited for magnetogenesis. In particular, a scenario where the number of extra dimensions D=4 and the cosmological constant is nonzero turns out to be best suited for generating primordial magnetic fields. It is shown that f