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Sample records for allan hills ice

  1. Uranium series dating of Allan Hills ice

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.

    1986-01-01

    Uranium-238 decay series nuclides dissolved in Antarctic ice samples were measured in areas of both high and low concentrations of volcanic glass shards. Ice from the Allan Hills site (high shard content) had high Ra-226, Th-230 and U-234 activities but similarly low U-238 activities in comparison with Antarctic ice samples without shards. The Ra-226, Th-230 and U-234 excesses were found to be proportional to the shard content, while the U-238 decay series results were consistent with the assumption that alpha decay products recoiled into the ice from the shards. Through this method of uranium series dating, it was learned that the Allen Hills Cul de Sac ice is approximately 325,000 years old.

  2. Carbon-14 ages of Allan Hills meteorites and ice

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.; Norris, T.

    1982-01-01

    Allan Hills is a blue ice region of approximately 100 sq km area in Antarctica where many meteorites have been found exposed on the ice. The terrestrial ages of the Allan Hills meteorites, which are obtained from their cosmogenic nuclide abundances are important time markers which can reflect the history of ice movement to the site. The principal purpose in studying the terrestrial ages of ALHA meteorites is to locate samples of ancient ice and analyze their trapped gas contents. Attention is given to the C-14 and Ar-39 terrestrial ages of ALHA meteorites, and C-14 ages and trapped gas compositions in ice samples. On the basis of the obtained C-14 terrestrial ages, and Cl-36 and Al-26 results reported by others, it is concluded that most ALHA meteorites fell between 20,000 and 200,000 years ago.

  3. The natural thermoluminescence of meteorites. V - Ordinary chondrites at the Allan Hills ice fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Hazel; Sears, Derek W. G.

    1993-01-01

    Natural thermoluminescence (TL) data have been obtained for 167 ordinary chondrites from the ice fields in the vicinity of the Allan Hills in Victoria Land, Antarctica, in order to investigate their thermal and radiation history, pairing, terrestrial age, and concentration mechanisms. Natural TL values for meteorites from the Main ice field are fairly low, while the Farwestern field shows a spread with many values 30-80 krad, suggestive of less than 150-ka terrestrial ages. There appear to be trends in TL levels within individual ice fields which are suggestive of directions of ice movement at these sites during the period of meteorite concentration. These directions seem to be confirmed by the orientations of elongation preserved in meteorite pairing groups. The proportion of meteorites with very low natural TL levels at each field is comparable to that observed at the Lewis Cliff site and for modern non-Antarctic falls and is also similar to the fraction of small perihelia orbits calculated from fireball and fall observations. Induced TL data for meteorites from the Allan Hills confirm trends which show that a select group of H chondrites from the Antarctic experienced a different extraterrestrial thermal history to that of non-Antarctic H chondrites.

  4. Atmospheric composition 1 million years ago from blue ice in the Allan Hills, Antarctica.

    PubMed

    Higgins, John A; Kurbatov, Andrei V; Spaulding, Nicole E; Brook, Ed; Introne, Douglas S; Chimiak, Laura M; Yan, Yuzhen; Mayewski, Paul A; Bender, Michael L

    2015-06-02

    Here, we present direct measurements of atmospheric composition and Antarctic climate from the mid-Pleistocene (∼1 Ma) from ice cores drilled in the Allan Hills blue ice area, Antarctica. The 1-Ma ice is dated from the deficit in (40)Ar relative to the modern atmosphere and is present as a stratigraphically disturbed 12-m section at the base of a 126-m ice core. The 1-Ma ice appears to represent most of the amplitude of contemporaneous climate cycles and CO2 and CH4 concentrations in the ice range from 221 to 277 ppm and 411 to 569 parts per billion (ppb), respectively. These concentrations, together with measured δD of the ice, are at the warm end of the field for glacial-interglacial cycles of the last 800 ky and span only about one-half of the range. The highest CO2 values in the 1-Ma ice fall within the range of interglacial values of the last 400 ka but are up to 7 ppm higher than any interglacial values between 450 and 800 ka. The lowest CO2 values are 30 ppm higher than during any glacial period between 450 and 800 ka. This study shows that the coupling of Antarctic temperature and atmospheric CO2 extended into the mid-Pleistocene and demonstrates the feasibility of discontinuously extending the current ice core record beyond 800 ka by shallow coring in Antarctic blue ice areas.

  5. Atmospheric composition 1 million years ago from blue ice in the Allan Hills, Antarctica

    PubMed Central

    Higgins, John A.; Kurbatov, Andrei V.; Spaulding, Nicole E.; Brook, Ed; Introne, Douglas S.; Chimiak, Laura M.; Yan, Yuzhen; Mayewski, Paul A.; Bender, Michael L.

    2015-01-01

    Here, we present direct measurements of atmospheric composition and Antarctic climate from the mid-Pleistocene (∼1 Ma) from ice cores drilled in the Allan Hills blue ice area, Antarctica. The 1-Ma ice is dated from the deficit in 40Ar relative to the modern atmosphere and is present as a stratigraphically disturbed 12-m section at the base of a 126-m ice core. The 1-Ma ice appears to represent most of the amplitude of contemporaneous climate cycles and CO2 and CH4 concentrations in the ice range from 221 to 277 ppm and 411 to 569 parts per billion (ppb), respectively. These concentrations, together with measured δD of the ice, are at the warm end of the field for glacial–interglacial cycles of the last 800 ky and span only about one-half of the range. The highest CO2 values in the 1-Ma ice fall within the range of interglacial values of the last 400 ka but are up to 7 ppm higher than any interglacial values between 450 and 800 ka. The lowest CO2 values are 30 ppm higher than during any glacial period between 450 and 800 ka. This study shows that the coupling of Antarctic temperature and atmospheric CO2 extended into the mid-Pleistocene and demonstrates the feasibility of discontinuously extending the current ice core record beyond 800 ka by shallow coring in Antarctic blue ice areas. PMID:25964367

  6. The Natural Thermoluminescence of Meteorites. Part 5; Ordinary Chondrites at the Allan Hills Ice Fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Hazel; Sears, Derek W. G.

    1993-01-01

    Natural thermoluminescence (TL) data have been obtained for 167 ordinary chondrites from the ice fields in the vicinity of the Allan Hills in Victoria Land, Antarctica, in order to investigate their thermal and radiation history, pairing, terrestrial age, and concentration mechanisms. Using fairly conservative criteria (including natural and induced TL, find location, and petrographic data), the 167 meteorite fragments are thought to represent a maximum of 129 separate meteorites. Natural TL values for meteorites from the Main ice field are fairly low (typically 5-30 krad, indicative of terrestrial ages of approx. 400 ka), while the Far western field shows a spread with many values 30-80 krad, suggestive of less then 150-ka terrestrial ages. There appear to be trends in TL levels within individual ice fields which are suggestive of directions of ice movement at these sites during the period of meteorite concentration. These directions seem to be confirmed by the orientations of elongation preserved in meteorite pairing groups. The proportion of meteorites with very low natural TL levels (less then 5 krad) at each field is comparable to that observed at the Lewis Cliff site and for modern non-Antarctic falls and is also similar to the fraction of small perihelia (less then 0.85 AU) orbits calculated from fireball and fall observations. Induced TL data for meteorites from the Allan Hills confirm trends observed for meteorites collected during the 1977/1978 and 1978/1979 field seasons which show that a select group of H chondrites from the Antarctic experienced a different extraterrestrial thermal history to that of non-Antarctic H chondrites.

  7. Proposed Ice Flow, Given 200m and 400m Additional Ice in the Allan Hills Region, Antarctica: Implications for Meteorite Concentration

    NASA Astrophysics Data System (ADS)

    Traub-Metlay, S.; Cassidy, W. A.

    1992-07-01

    The Allan Hills-David Glacier region contains some of the most highly populated meteorite stranding surfaces in Antarctica. Nearly 2000 meteorites have to date been collected from the icefields associated with the Allan Hills, and nearly 1500 from areas around Elephant Moraine. While much attention has been focused on the current geological and glaciological conditions of these stranding surfaces, less work has been done concerning what they may have looked like in the past, when ice thicknesses may have been greater. In this study, conjectural maps of the current Allan Hills area with 200 meters and 400 meters of additional ice cover each are analyzed for probable regional and local ice flow patterns. A dramatic decrease in ice thickness over a relatively brief period of time could result either from climatic change or a geologically rapid regional uplift. Delisle and Sievers (1991) noted that the valley between the Allan Hills Main Icefield and the Allan Hills resembles a half-graben resulting from east-west extensional tectonics, and that the mesa-like bedrock features associated with the Near Western and Mid Western Icefields resemble fault blocks. They concluded that the Allan Hills area icefields may have become active stranding surfaces as a result of a regional uplift within the past 1-2 million years, assuming a current rate of uplift in the Allan Hills region of ~100 meters/million years. Whether the cause was climatic or tectonic, generalized maps of current ice contours plus 400 and 200 meters ice may provide views of what the Allan Hills region looked like just before activation of the modern meteorite stranding surfaces (Figs. 1 and 2). At an ice thickness greater by 400 meters, ice could flow smoothly over the Allan Hills and would drain down to the Mawson Glacier via the Odell Glacier, east of the Allan Hills; down the Manhaul Bay depression between the east and west arms of Allan Hills; and down the half-graben discovered by Delisle and Sievers

  8. Age of Allan Hills 82102, a meteorite found inside the ice

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Jull, A. J. T.; Bonani, G.; Suter, M.; Woelfli, W.

    1989-01-01

    The terrestrial age of a meteorite that was recovered from below the surface of Antarctic ice is reported, and it is argued that this represents a measurement of the age of the ice itself. The cosmogenic radionuclides Be-10, C-14, Al-26, Cl-36, and Mn-53 are measured in the meteorite and Be-10 and Cl-36 in the ice. A terrestrial age of 11,000 yr is obtained for the meteorite, which suggests that the snow accumulation area where it fell was only a few tens of km away.

  9. The Allan Hills icefield and its relationship to meteorite concentration

    NASA Technical Reports Server (NTRS)

    Annexstad, J. O.

    1982-01-01

    The Allan Hills icefield is described by as a limited icefield that has large concentrations of meteorites. The meteorites appear to be concentrated on the lower limb of an ice monocline with other finds scattered throughout the field. In an attempt to understand the mechanisms of meteorite concentration, a triangulation chain was established across the icefield. This chain is composed of 20 stations, two of which are on bedrock, and extends westward from the Allan Hills a distance of 15 kilometers. The triangulation chain and its relationship to the meteorite concentrations is shown.

  10. Exposure of Allan Hills 84001 and other achondrites on the Antarctic ice.

    PubMed

    Krahenbuhl, U; Noll, K; Dobeli, M; Grambole, D; Herrmann, F; Tobler, L

    1998-07-01

    The enrichment of F on Antarctic meteorites is the result of their exposure to the atmosphere, and its measurement allows a subdivision of the terrestrial age into a duration of exposure on the ice and the time a meteorite was enclosed by the ice. In many cases, the periods of surface exposure are only small fractions of the terrestrial ages of meteorites collected in Antarctica. The enrichment of F on the surfaces of Antarctic achondrites was investigated by means of nuclear reaction analysis (NRA): scanning proton beams with an energy of 2.7 and 3.4 MeV were used to induce the reactions 19F(p, alpha gamma)16O and 19F(p,p gamma)19F, respectively. Gamma signals proportional to the F content were measured. The following Antarctic achondrites were investigated: Martian meteorite ALH 84001; diogenite ALHA77256; the eucrites ALHA81011 and ALHA78132; and in addition, the H5 chondrite ALHA79025. For ALH 84001, our data indicate a period of exposure on the ice of <500 years. Thus, this specimen was enclosed in the ice >95% of its terrestrial age of 13 000 years.

  11. Exposure and terrestrial ages of four Allan Hills Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Kirsten, T.; Ries, D.; Fireman, E. L.

    1978-01-01

    Terrestrial ages of meteorites are based on the amount of cosmic-ray-produced radioactivity in the sample and the number of observed falls that have similar cosmic-ray exposure histories. The cosmic-ray exposures are obtained from the stable noble gas isotopes. Noble gas isotopes are measured by high-sensitivity mass spectrometry. In the present study, the noble gas contents were measured in four Allan Hill meteorites (No. 5, No. 6, No. 7, and No. 8), whose C-14, Al-26, and Mn-53 radioactivities are known. These meteorites are of particular interest because they belong to a large assemblage of distinct meteorites that lie exposed on a small (110 sq km) area of ice near the Allan Hills.

  12. Modal comparison of Yamato and Allan Hills polymict eucrites

    NASA Technical Reports Server (NTRS)

    Delaney, J. S.; Prinz, M.; Takeda, H.

    1983-01-01

    Seven Yamato and six Allan Hills polymict eucrite specimens were compared by modal analysis. The analyses reveal differences of plagioclase and pyroxene content between the two groups. The Yamato suite has more 'pigeonitic' pyroxene and less plagioclase and low-calcium pyroxene than the Allan Hills suite. Variations within each suite are small and three sections of Allan Hills A78040 are more variable than the Allen Hills suite considered as a group. Modal data provides a basis for pairing polymict eucrite specimens when used together with mineralogical and petrographic criteria. Modal data furthermore confirms the presence of several rock types previously identified using pyroxene crystallography and hints at the presence of an augite-rich component.

  13. Allan Hills 77005 - A new meteorite type found in Antarctica

    NASA Technical Reports Server (NTRS)

    Mcsween, H. Y., Jr.; Taylor, L. A.; Stolper, E. M.

    1979-01-01

    A unique 482.5 g meteorite found in Antarctica appears to be related by igneous differentiation to shergottite achondrites, which have close similarities with terrestrial basaltic rocks. Zoned maskelynite with similar compositional ranges and plagioclase of such intermediate compositions as are unknown in other achondrites occur in both shergottites and the Allan Hills meteorite. The degree of silica saturation, however, strongly distinguishes the two meteorite types. It is suggested that the Allan Hills meteorite may represent a cumulate rock formed earlier than the shergottites from the same or a similar parent magma.

  14. Radio-Echo Sounding in the Allan Hills, Antarctica, in Support of the Meteorite Field Program.

    DTIC Science & Technology

    1980-05-01

    ice. The results also revealed internal layering within the snow on Ross Island and in the snow filling an ice depres- sion west of Allan Nunatak ...Radio-echo sounding also gave the depth to bedrock near the west side of Allan Nunatak . The greatest ice depth measured was 310 m. • . 9Q3...Institute of Polar Research had installed across the blue ice surface extending westward from the Allan Nunatak . Allan Nunatak is located in the Allan

  15. Noble gases in twenty Yamato H-chondrites: Comparison with Allan Hills chondrites and modern falls

    NASA Technical Reports Server (NTRS)

    Loeken, TH.; Scherer, P.; Schultz, L.

    1993-01-01

    Concentration and isotopic composition of noble gases have been measured in 20 H-chrondrites found on the Yamato Mountains ice fields in Antarctica. The distribution of exposure ages as well as of radiogenic He-4 contents is similar to that of H-chrondrites collected at the Allan Hills site. Furthermore, a comparison of the noble gas record of Antarctic H-chrondrites and finds or falls from non-Antarctic areas gives no support to the suggestion that Antarctic H-chrondrites and modern falls derive from differing interplanetary meteorite populations.

  16. Chemical characterization of a unique chondrite - Allan Hills 85085

    NASA Technical Reports Server (NTRS)

    Gosselin, David C.; Laul, J. C.

    1990-01-01

    Allan Hills 85085 is a new and very important addition to the growing list of unique carbonaceous chondrites because of its unique chemical and mineralogical properties. This chemical study provides more precise data on the major, minor, and trace element characteristics of ALH85085. ALH85085 has compositional, petrological, and isotopic affinities to AL Rais and Renazzo, and to Bencubbin-Weatherford. The similarities to Al Rais and Renazzo suggest similar formation locations and thermal processing, possibly in the vicinity of CI chondrites. Petrologic, compositional and isotopic studies indicate that the components that control the abundance of the various refractory and volatile elements were not allowed to equilibrate with the nebula as conditions changed, explaining the inconsistencies in the classification of these meteorites using known taxonomic parameters.

  17. A new kind of primitive chondrite, Allan Hills 85085

    NASA Technical Reports Server (NTRS)

    Scott, Edward R. D.

    1988-01-01

    Allan Hills (ALH) 85085, a chemically and mineralogically unique chondrite whose components have suffered little metamorphism or alteration, is discussed. It is found that ALH 85085 has 4 wt pct chondrules (mean diameter 16 microns), 36 wt pct Fe, Ni, 56 wt pct lithic and mineral silicate fragments, and 2 wt pct trolite. It is suggested that, with the exception of matrix lumps, the components of ALH 85085 formed and accreted in the solar nebula. It is shown that ALH 85085 does not belong to any of the nine chondrite groups and is very different from Kakangari. Similarities between ALH 85085 and Bencubbin and Weatherford suggest that the latter two primitive meteorites may be chondrites with high metal abundances and very large, partly fragmented chondrules.

  18. Petrogenetic relationship between Allan Hills 77005 and other achondrites

    NASA Technical Reports Server (NTRS)

    Mcsween, H. Y., Jr.; Taylor, L. A.; Stolper, E. M.; Muntean, R. A.; Okelley, G. D.; Eldridge, J. S.; Biswas, S.; Ngo, H. T.; Lipschutz, M. E.

    1979-01-01

    The paper presents chemical and petrologic data relating the Allan Hills (ALHA) 77005 achondrite from Antarctica and explores their petrogenetic relationship with the shergottites. Petrologic similarities with the latter in terms of mineralogy, oxidation state, inferred source region composition, and shock ages suggest a genetic relationship, also indicated by volatile to involatile element ratios and abundances of other trace elements. ALHA 77005 may be a cumulate crystallized from a liquid parental to materials from which the shergottites crystallized or a sample of peridotite from which shergottite parent liquids were derived. Chemical similarities with terrestrial ultramafic rocks suggest that it provides an additional sample of the only other solar system body with basalt source origins chemically similar to the upper earth mantle.

  19. The History of Allan Hills 84001 Revised: Multiple Shock Events

    NASA Technical Reports Server (NTRS)

    Treiman, Allan H.

    1998-01-01

    The geologic history of Martian meteorite Allan Hills (ALH) 84001 is more complex than previously recognized, with evidence for four or five crater-forming impacts onto Mars. This history of repeated deformation and shock metamorphism appears to weaken some arguments that have been offered for and against the hypothesis of ancient Martian life in ALH 84001. Allan Hills 84001 formed originally from basaltic magma. Its first impact event (I1) is inferred from the deformation (D1) that produced the granular-textured bands ("crush zones") that transect the original igneous fabric. Deformation D1 is characterized by intense shear and may represent excavation or rebound flow of rock beneath a large impact crater. An intense thermal metamorphism followed D1 and may be related to it. The next impact (I2) produced fractures, (Fr2) in which carbonate "pancakes" were deposited and produced feldspathic glass from some of the igneous feldspars and silica. After I2, carbonate pancakes and globules were deposited in Fr2 fractures and replaced feldspathic glass and possibly crystalline silicates. Next, feldspars, feldspathic glass, and possibly some carbonates were mobilized and melted in the third impact (I3). Microfaulting, intense fracturing, and shear are also associated with 13. In the fourth impact (I4), the rock was fractured and deformed without significant heating, which permitted remnant magnetization directions to vary across fracture surfaces. Finally, ALH 84001 was ejected from Mars in event I5, which could be identical to I4. This history of multiple impacts is consistent with the photogeology of the Martian highlands and may help resolve some apparent contradictions among recent results on ALH 84001. For example, the submicron rounded magnetite grains in the carbonate globules could be contemporaneous with carbonate deposition, whereas the elongate magnetite grains, epitaxial on carbonates, could be ascribed to vapor-phase deposition during I3.

  20. Exploring Thermal Signatures in the Experimentally Heated CM Carbonaceous Chondrite Allan Hills 83100

    NASA Astrophysics Data System (ADS)

    Lindgren, P.; Andreassen, A. M.; Lee, M. R.; Sparkes, R.; Greenwood, R. C.; Franchi, I. A.

    2016-08-01

    We have examined the effect of experimental heating on water/hydroxyl content, carbon structure, O-isotope signature, and sulphide and carbonate microstructure in the highly aqueously altered meteorite Allan Hills 83100.

  1. Classification of the Allan Hills A77307 meteorite

    NASA Technical Reports Server (NTRS)

    Sears, D. W. G.; Ross, M.

    1983-01-01

    Thermoluminescence (TL) measurements on Allan Hills A77307 (AH), a carbonaceous chondrite found in Antarctica, are compared with those on other chondrite and applied to its classification. Two lithologically different 250-mg samples were ground, freed of magnetic material, and ground again to pass a 100-micron sieve. Aliquots of 4 mg were heated to 500 C, exposed to beta radiation from a Sr-90 source, and heated at a rate of 7.3 C/sec in N2. TL was measured with a photomultiplier tube fitted with thermal and blue filters. Glow curves for AH and for seven other, established CO-type chondrites area presented, all exhibiting two major peaks of TL sensitivity. The peaks for the seven CO-type chondrites are found at 91 + or - 7 C and at 203 + or - 11 C; those for AH at 170 + or - 17 C and at approximately 250 C. This difference is considered significant and not due to random fluctuation or a typical sampling. From this comparison and from consideration of the weathering, preterrestrial-alteration, petrological and compositional evidence on AH, it is concluded that AH is a unique chondrite, possessing both similarities to and differences from the CO class.

  2. Investigations into an unknown organism on the martian meteorite Allan Hills 84001.

    PubMed

    Steele, A; Goddard, D T; Stapleton, D; Toporski, J K; Peters, V; Bassinger, V; Sharples, G; Wynn-Williams, D D; McKay, D S

    2000-03-01

    Examination of fracture surfaces near the fusion crust of the martian meteorite Allan Hills (ALH) 84001 have been conducted using scanning electron microscopy (SEM) and atomic force microscopy (AFM) and has revealed structures strongly resembling mycelium. These structures were compared with similar structures found in Antarctic cryptoendolithic communities. On morphology alone, we conclude that these features are not only terrestrial in origin but probably belong to a member of the Actinomycetales, which we consider was introduced during the Antarctic residency of this meteorite. If true, this is the first documented account of terrestrial microbial activity within a meteorite from the Antarctic blue ice fields. These structures, however, do not bear any resemblance to those postulated to be martian biota, although they are a probable source of the organic contaminants previously reported in this meteorite.

  3. Investigations into an unknown organism on the martian meteorite Allan Hills 84001

    NASA Technical Reports Server (NTRS)

    Steele, A.; Goddard, D. T.; Stapleton, D.; Toporski, J. K.; Peters, V.; Bassinger, V.; Sharples, G.; Wynn-Williams, D. D.; McKay, D. S.

    2000-01-01

    Examination of fracture surfaces near the fusion crust of the martian meteorite Allan Hills (ALH) 84001 have been conducted using scanning electron microscopy (SEM) and atomic force microscopy (AFM) and has revealed structures strongly resembling mycelium. These structures were compared with similar structures found in Antarctic cryptoendolithic communities. On morphology alone, we conclude that these features are not only terrestrial in origin but probably belong to a member of the Actinomycetales, which we consider was introduced during the Antarctic residency of this meteorite. If true, this is the first documented account of terrestrial microbial activity within a meteorite from the Antarctic blue ice fields. These structures, however, do not bear any resemblance to those postulated to be martian biota, although they are a probable source of the organic contaminants previously reported in this meteorite.

  4. A new LL3 chondrite, Allan Hills A79003, and observations on matrices in ordinary chondrites

    NASA Technical Reports Server (NTRS)

    Scott, E. R. D.; Taylor, G. J.; Maggiore, P.

    1982-01-01

    Allan Hills A79003 is an LL3 chondrite with a petrologic subtype of 3.4 + or - 0.2. Contrary to previous suggestions, it is not paired with other Allan Hills specimens. It contains haxonite, (Fe,Ni)23C6; shock-melted, 'fizzed' metal-troilite intergrowths; and translucent, glassy-looking Huss matrix (fine-grained, Fe-rich silicate matrix), in addition to the normal opaque and recrystallized varieties of Huss matrix. Some chondrules are partly coated with opaque matrix, others with translucent matrix. Translucent matrix is more uniform in composition and contains less S, CaO and FeO and more MgO than the opaque variety. Both kinds of matrix rimmed chondrules before consolidation of the meteorite.

  5. Cosmic-ray-produced Cl-36 and Mn-53 in Allan Hills-77 meteorites

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Murrell, M. T.; Arnold, J. R.; Finkel, R. C.; Elmore, D.; Ferraro, R. D.; Gove, H. E.

    1981-01-01

    Cosmic-ray-produced Mn-53 has been determined by neutron activation in nine Allan Hills-77 meteorites. Additionally, Cl-36 has been measured in seven of these objects using tandem accelerator mass spectrometry. These results, along with C-14 and Al-26 concentrations determined elsewhere, yield terrestrial ages ranging from 10,000 to 700,000 years. Weathering was not found to result in Mn-53 loss.

  6. The discovery and initial characterization of Allan Hills 81005 - The first lunar meteorite

    NASA Technical Reports Server (NTRS)

    Marvin, U. B.

    1983-01-01

    Antarctic meteorite ALHA81005, discovered in the Allan Hills region of Victoria Land, is a polymict anorthositic breccia which differs from other meteorites in mineralogical and chemical composition but is strikingly similar to lunar highlands soil breccias. The petrologic character and several independent lines of evidence identify ALHA81005 as a meteorite from the moon. Two small clasts of probable mare basalt occur among the highlands lithologies in Thin Section 81005,22. This lunar specimen, which shows relatively minor shock effects, has generated new ideas on the types of planetary samples found on the earth.

  7. A unique type 3 ordinary chondrite containing graphite-magnetite aggregates - Allan Hills A77011

    NASA Technical Reports Server (NTRS)

    Mckinley, S. G.; Scott, E. R. D.; Taylor, G. J.; Keil, K.

    1982-01-01

    ALHA 77011, which is the object of study in the present investigation, is a chondrite of the 1977 meteorite collection from Allan Hills, Antarctica. It contains an opaque and recrystallized silicate matrix (Huss matrix) and numerous aggregates consisting of micron- and submicron-sized graphite and magnetite. It is pointed out that no abundant graphite-magnetite aggregates could be observed in other type 3 ordinary chondrites, except for Sharps. Attention is given to the results of a modal analysis, relations between ALHA 77011 and other type 3 ordinary chondrites, and the association of graphite-magnetite and metallic Fe, Ni. The discovery of graphite-magnetite aggregates in type 3 ordinary chondrites is found to suggest that this material may have been an important component in the formation of ordinary chondrites.

  8. Composition of bulk samples and a possible pristine clast from Allan Hills A81005

    NASA Technical Reports Server (NTRS)

    Boynton, W. V.; Hill, D. H.

    1983-01-01

    Abundances of thirty-five elements were determined in two bulk samples and a white clast in the Allan Hills A81005 meteorite. High siderophile element content indicates that the sample is a regolith breccia. An Fe/Mn ratio of 77 in this meteorite eliminates parent bodies of known differentiated meteorites as the source of ALHA 81005. The incompatible elements are very similar to those found in most lunar highlands rocks, and provide very strong evidence that the sample is lunar in origin. The clast sample has the trace element pattern of a lunar anorthosite and is very low in KREEP and siderophile elements. It may be a fragment of a pristine lunar rock.

  9. Element distribution and noble gas isotopic abundances in lunar meteorite Allan Hills A81005

    NASA Technical Reports Server (NTRS)

    Kraehenbuehl, U.; Eugster, O.; Niedermann, S.

    1986-01-01

    Antarctic meteorite ALLAN HILLS A81005, an anorthositic breccia, is recognized to be of lunar origin. The noble gases in this meteorite were analyzed and found to be solar-wind implanted gases, whose absolute and relative concentrations are quite similar to those in lunar regolith samples. A sample of this meteorite was obtained for the analysis of the noble gas isotopes, including Kr(81), and for the determination of the elemental abundances. In order to better determine the volume derived from the surface correlated gases, grain size fractions were prepared. The results of the instrumental measurements of the gamma radiation are listed. From the amounts of cosmic ray produced noble gases and respective production rates, the lunar surface residence times were calculated. It was concluded that the lunar surface time is about half a billion years.

  10. Allan Hills 76005 Polymict Eucrite Pairing Group: Curatorial and Scientific Update on a Jointly Curated Meteorite

    NASA Technical Reports Server (NTRS)

    Righter, K.

    2011-01-01

    Allan Hills 76005 (or 765) was collected by the joint US-Japan field search for meteorites in 1976-77. It was described in detail as "pale gray in color and consists of finely divided macrocrystalline pyroxene-rich matrix that contains abundant clastic fragments: (1) Clasts of white, plagioclase-rich rocks. (2) Medium-gray, partly devitrified, cryptocrystalline. (3) Monomineralic fragments and grains of pyroxene, plagioclases, oxide minerals, sulfides, and metal. In overall appearance it is very similar to some lunar breccias." Subsequent studies found a great diversity of basaltic clast textures and compositions, and therefore it is best classified as a polymict eucrite. Samples from the 1976-77, 77-78, and 78-79 field seasons (76, 77, and 78 prefixes) were split between US and Japan (NIPR). The US specimens are currently at NASA-JSC, Smithsonian Institution, or the Field Museum in Chicago. After this initial finding of ALH 76005, the next year s team recovered one additional mass ALH 77302, and then four additional masses were found during the third season ALH 78040 and ALH 78132, 78158 and 78165. The joint US-Japan collection effort ended after three years and the US began collecting in the Trans-Antarctic Mountains with the 1979-80 and subsequent field seasons. ALH 79017 and ALH 80102 were recovered in these first two years, and then in 1981-82 field season, 6 additional masses were recovered from the Allan Hills. Of course it took some time to establish pairing of all of these specimens, but altogether the samples comprise 4292.4 g of material. Here will be summarized the scientific findings as well as some curatorial details of how specimens have been subdivided and allocated for study. A detailed summary is also presented on the NASA-JSC curation webpage for the HED meteorite compendium.

  11. Metal with anomalously low Ni and Ge concentrations in the Allan Hills A77081 winonaite

    NASA Technical Reports Server (NTRS)

    Kracher, Alfred

    1988-01-01

    The Ge content of metal in the Allan Hills A77081 winonaite was determined by high-sensitivity electron microprobe analysis. By optimizing analytical conditions for Ge determination, a detection limit of about 75 ppm could be achieved. In A77081 some small kamacite grains contain less Ni and Ge and more Co than coarse-grained metal. These small grains are always associated with sulfide, raising the possibility that anomalous metal is related to eutectic melting. However, when published partition coefficients for Ni and Ge in the Fe-Ni-S system are used to model fractionation of these elements during eutectic melting, one finds that secondary metal should be enriched in Ni and depleted in Ge. Thus, the positive Ni-Ge correlation found in this study is the opposite of the expected trend. No explanation for this discrepancy has yet been found. Nonetheless, the existence of anomalous metal is an indication that A77081, and probably other winonaites as well, have undergone some fractionation. This supports the notion that the high-temperature history of winonaites is related to the formation of IAB iron meteorites, whose silicate inclusions are very similar to winonaites.

  12. Extreme metamorphism in a firn core from the Allan Hills, Antarctica, as an analogue for glacial conditions

    NASA Astrophysics Data System (ADS)

    Dadic, Ruzica; Schneebeli, Martin; Bertler, Nancy; Schwikowski, Margit; Matzl, Margret

    2015-04-01

    Understanding processes in near-zero accumulation areas can help to better understand the ranges of isotopic composition in ice cores, particularly during ice ages, when accumulation rates were lower than today. Snow metamorphism is a primary driver of the transition from snow to ice and can be accompanied by altered isotopic compositions and chemical species concentration. High degree snow metamorphism, which results in major structural changes, is little-studied but has been identified in certain places in Antarctica. Here we report on a 5-m firn core collected adjacent to a blue-ice field in the Allan Hills, Antarctica. We determined the physical properties of the snow using computer tomography (microCT) and measured the isotopic composition of δD and δ18O, as well as 210Pb activity. The core shows a high degree of snow metamorphism and an exponential decrease in specific surface area (SSA), but no clear densification, with depth. The micro-CT measurements show a homogenous and stable structure throughout the entire core, with obvious erosion features in the near-surface, where high-resolution data is available. The observed firn structure is likely caused by a combination of unique depositional and post-depositional processes. The defining depositional process is the impact deposition under high winds and with a high initial density. The defining post-depositional processes are a) increased moisture transport due to forced ventilation and high winds and b) decades of temperature-gradient driven metamorphic growth in the near surface due to prolonged exposure to seasonal temperature cycling. Both post-processes are enhanced in low accumulation regions where snow stays close to surface for a long time. We observe an irregular signal in δD and δ18O that does not follow the stratigraphic sequence. The isotopic signal is likely caused by the same post-depositional processes that are responsible for the firn structure, and that are driven by local climate

  13. Carbonates in fractures of Martian meteorite Allan Hills 84001: petrologic evidence for impact origin

    NASA Technical Reports Server (NTRS)

    Scott, E. R.; Krot, A. N.; Yamaguchi, A.

    1998-01-01

    Carbonates in Martian meteorite Allan Hills 84001 occur as grains on pyroxene grain boundaries, in crushed zones, and as disks, veins, and irregularly shaped grains in healed pyroxene fractures. Some carbonate disks have tapered Mg-rich edges and are accompanied by smaller, thinner and relatively homogeneous, magnesite microdisks. Except for the microdisks, all types of carbonate grains show the same unique chemical zoning pattern on MgCO3-FeCO3-CaCO3 plots. This chemical characteristic and the close spatial association of diverse carbonate types show that all carbonates formed by a similar process. The heterogeneous distribution of carbonates in fractures, tapered shapes of some disks, and the localized occurrence of Mg-rich microdisks appear to be incompatible with growth from an externally derived CO2-rich fluid that changed in composition over time. These features suggest instead that the fractures were closed as carbonates grew from an internally derived fluid and that the microdisks formed from a residual Mg-rich fluid that was squeezed along fractures. Carbonate in pyroxene fractures is most abundant near grains of plagioclase glass that are located on pyroxene grain boundaries and commonly contain major or minor amounts of carbonate. We infer that carbonates in fractures formed from grain boundary carbonates associated with plagiociase that were melted by impact and dispersed into the surrounding fractured pyroxene. Carbonates in fractures, which include those studied by McKay et al. (1996), could not have formed at low temperatures and preserved mineralogical evidence for Martian organisms.

  14. Bulk and Stable Isotopic Compositions of Carbonate Minerals in Martian Meteorite Allan Hills 84001: No Proof of High Formation Temperature

    NASA Technical Reports Server (NTRS)

    Treiman, Allan H.; Romanek, Christopher S.

    1998-01-01

    Understanding the origin of carbonate minerals in the Martian meteorite Allan Hills (ALH) 84001 is crucial to evaluating the hypothesis that they contain traces of ancient Martian life. Using arguments based on chemical equilibria among carbonates and fluids, an origin at greater than 650 C (inimical to life) has been proposed. However, the bulk and stable isotopic compositions of the carbonate minerals are open to multiple interpretations and so lend no particular support to a high-temperature origin. Other methods (possibly less direct) will have to be used to determine the formation temperature of the carbonates in ALH 84001.

  15. Regolith breccia Allan Hills A81005 - Evidence of lunar origin, and petrography of pristine and nonpristine clasts

    NASA Technical Reports Server (NTRS)

    Warren, P. H.; Taylor, G. J.; Keil, K.

    1983-01-01

    It is shown that the ratios of MnO/FeO in pyroxene, texture (abundant brown and swirly glass, which are typical of lunar regolith breccias) and overall composition (approximately 75 percent plagioclase) indicate a lunar origin for the regolith breccia Allan Hills A81005, presumably from an unsampled region of the moon. The rock is found to differ in detail from other regolith samples; for example, it has exceptionally low contents of Na and KREEP. In addition, a pristine clast is found to contain exceptionally coarse augite in comparison with similar Apollo samples. It is found that ALHA81005 is not perceptibly more shocked than typical Apollo regolith breccias. It is concluded that the discovery of this rock on earth strengthens the suggestion that SNC achondrites were derived by impact ejection from Mars.

  16. Geological evolution of the Coombs Allan Hills area, Ferrar large igneous province, Antarctica: Debris avalanches, mafic pyroclastic density currents, phreatocauldrons

    NASA Astrophysics Data System (ADS)

    Ross, Pierre-Simon; White, James D. L.; McClintock, Murray

    2008-05-01

    The Jurassic Ferrar large igneous province of Antarctica comprises igneous intrusions, flood lavas, and mafic volcaniclastic deposits (now lithified). The latter rocks are particularly diverse and well-exposed in the Coombs-Allan Hills area of South Victoria Land, where they are assigned to the Mawson Formation. In this paper we use these rocks in conjunction with the pre-Ferrar sedimentary rocks (Beacon Supergroup) and the lavas themselves (Kirkpatrick Basalt) to reconstruct the geomorphological and geological evolution of the landscape. In the Early Jurassic, the surface of the region was an alluvial plain, with perhaps 1 km of mostly continental siliciclastic sediments underlying it. After the fall of silicic ash from an unknown but probably distal source, mafic magmatism of the Ferrar province began. The oldest record of this event at Allan Hills is a ≤ 180 m-thick debris-avalanche deposit (member m1 of the Mawson Formation) which contains globular domains of mafic igneous rock. These domains are inferred to represent dismembered Ferrar intrusions emplaced in the source area of the debris avalanche; shallow emplacement of Ferrar magmas caused a slope failure that mobilized the uppermost Beacon Supergroup, and the silicic ash deposits, into a pre-existing valley or basin. The period which followed ('Mawson time') was the main stage for explosive eruptions in the Ferrar province, and several cubic kilometres of both new magma and sedimentary rock were fragmented over many years. Phreatomagmatic explosions were the dominant fragmentation mechanism, with magma-water interaction taking place in both sedimentary aquifers and existing vents filled by volcaniclastic debris. At Coombs Hills, a vent complex or 'phreatocauldron' was formed by coalescence of diatreme-like structures; at Allan Hills, member m2 of the Mawson Formation consists mostly of thick, coarse-grained, poorly sorted layers inferred to represent the lithified deposits of pyroclastic density currents

  17. Fine-Grained Rims in the Allan Hills 81002 and Lewis Cliff 90500 CM2 Meteorites: Their Origin and Modification

    NASA Technical Reports Server (NTRS)

    Hua, X.; Wang, J.; Buseck, P. R.

    2002-01-01

    Antarctic CM meteorites Allan Hills (ALH) 8 1002 and Lewis Cliff (LEW) 90500 contain abundant fine-grained rims (FGRs) that surround a variety of coarse-grained objects. FGRs from both meteorites have similar compositions and petrographic features, independent of their enclosed objects. The FGRs are chemically homogeneous at the 10 m scale for major and minor elements and at the 25 m scale for trace elements. They display accretionary features and contain large amounts of volatiles, presumably water. They are depleted in Ca, Mn, and S but enriched in P. All FGRs show a slightly fractionated rare earth element (REE) pattern, with enrichments of Gd and Yb and depletion of Er. Gd is twice as abundant as Er. Our results indicate that those FGRs are not genetically related to their enclosed cores. They were sampled from a reservoir of homogeneously mixed dust, prior to accretion to their parent body. The rim materials subsequently experienced aqueous alteration under identical conditions. Based on their mineral, textural, and especially chemical similarities, we conclude that ALH 8 1002 and LEW 90500 likely have a similar or identical source.

  18. Olivine in Martian Meteorite Allan Hills 84001: Evidence for a High-Temperature Origin and Implications for Signs of Life

    NASA Technical Reports Server (NTRS)

    Shearer, C. K.; Leshin, L. A.; Adcock, C. T.

    1999-01-01

    Olivine from Martian meteorite Allan Hills (ALH) 84001 occurs as clusters within orthopyroxene adjacent to fractures containing disrupted carbonate globules and feldspathic shock glass. The inclusions are irregular in shape and range in size from approx. 40 microns to submicrometer. Some of the inclusions are elongate and boudinage-like. The olivine grains are in sharp contact with the enclosing orthopyroxene and often contain small inclusions of chromite The olivine exhibits a very limited range of composition from Fo(sub 65) to Fo(sub 66) (n = 25). The delta(sup 18)O values of the olivine and orthopyroxene analyzed by ion microprobe range from +4.3 to +5.3% and are indistinguishable from each other within analytical uncertainty. The mineral chemistries, O-isotopic data, and textural relationships indicate that the olivine inclusions were produced at a temperature greater than 800 C. It is unlikely that the olivines formed during the same event that gave rise to the carbonates in ALH 84001, which have more elevated and variable delta(sup 18)O values, and were probably formed from fluids that were not in isotopic equilibrium with the orthopyroxene or olivine The reactions most likely instrumental in the formation of olivine could be either the dehydration of hydrous silicates that formed during carbonate precipitation or the reduction of orthopyroxene and spinel If the olivine was formed by either reaction during a postcarbonate beating event, the implications are profound with regards to the interpretations of McKay et al. Due to the low diffusion rates in carbonates, this rapid, high-temperature event would have resulted in the preservation of the fine-scale carbonate zoning' while partially devolatilizing select carbonate compositions on a submicrometer scale. This may have resulted in the formation of the minute magnetite grains that McKay et al attributed to biogenic activity.

  19. Thermoluminescence survey of 12 meteorites collected by the European 1988 Antarctic meteorite expedition to Allan Hills and the importance of acid washing for thermoluminescence sensitivity measurements

    NASA Technical Reports Server (NTRS)

    Benoit, P. H.; Sears, H.; Sears, D. W. G.

    1991-01-01

    Natural and induced thermoluminescence (TL) data are reported for 12 meteorites recovered from the Allan Hills region of Antarctica by the European field party during the 1988/1989 field season. The samples include one with extremely high natural TL, ALH88035, suggestive of exposure to unusually high radiation doses (i.e., low degrees of shielding), and one, ALH88034, whose low natural TL suggests reheating within the last 100,000 years. The remainder have natural TL values suggestive of terrestrial ages similar to those of other meteorites from Allan Hills. ALH88015 (L6) has induced TL data suggestive of intense shock. TL sensitivities of these meteorites are generally lower than observed falls of their petrologic types, as is also observed for Antarctic meteorites in general. Acid-washing experiments indicate that this is solely the result of terrestrial weathering rather than a nonterrestrial Antarctic-non-Antarctic difference. However, other TL parameters, such as natural TL and induced peak temperature-width, are unchanged by acid washing and are sensitive indicators of a meteorite's metamorphic and recent radiation history.

  20. The 'Ice Hill': An example of 'retarded deglaciation' in siberia

    NASA Astrophysics Data System (ADS)

    Astakhov, Valery I.; Isayeva, Lia L.

    the Pleistocene and Holocene diamictons with driftwood at the 'Ice Hill'. Such 'warm' diamictons may account for some Early Holocene and similar puzzling interglacial 'ice advances'.

  1. Carbonates in the Martian meteorite Allan Hills 84001 formed at 18 ± 4 °C in a near-surface aqueous environment

    PubMed Central

    Halevy, Itay; Fischer, Woodward W.; Eiler, John M.

    2011-01-01

    Despite evidence for liquid water at the surface of Mars during the Noachian epoch, the temperature of early aqueous environments has been impossible to establish, raising questions of whether the surface of Mars was ever warmer than today. We address this problem by determining the precipitation temperature of secondary carbonate minerals preserved in the oldest known sample of Mars’ crust—the approximately 4.1 billion-year-old meteorite Allan Hills 84001 (ALH84001). The formation environment of these carbonates, which are constrained to be slightly younger than the crystallization age of the rock (i.e., 3.9 to 4.0 billion years), has been poorly understood, hindering insight into the hydrologic and carbon cycles of earliest Mars. Using “clumped” isotope thermometry we find that the carbonates in ALH84001 precipitated at a temperature of approximately 18 °C, with water and carbon dioxide derived from the ancient Martian atmosphere. Furthermore, covarying carbonate carbon and oxygen isotope ratios are constrained to have formed at constant, low temperatures, pointing to deposition from a gradually evaporating, subsurface water body—likely a shallow aquifer (meters to tens of meters below the surface). Despite the mild temperatures, the apparently ephemeral nature of water in this environment leaves open the question of its habitability. PMID:21969543

  2. An abiotic origin for hydrocarbons in the Allan Hills 84001 martian meteorite through cooling of magmatic and impact-generated gases.

    PubMed

    Zolotov MYu; Shock, E L

    2000-05-01

    Thermodynamic calculations of metastable equilibria were used to evaluate the potential for abiotic synthesis of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in the martian meteorite Allan Hills (ALH) 84001. The calculations show that PAHs and normal alkanes could form metastably from CO, CO2, and H2 below approximately 250-300 degrees C during rapid cooling of trapped magmatic or impact-generated gases. Depending on temperature, bulk composition, and oxidation-reduction conditions, PAHs and normal alkanes can form simultaneously or separately. Moreover, PAHs can form at lower H/C ratios, higher CO/CO2 ratios, and higher temperatures than normal alkanes. Dry conditions with H/C ratios less than approximately 0.01-0.001 together with high CO/CO2 ratios also favor the formation of unalkylated PAHs. The observed abundance of PAHs, their low alkylation, and a variable but high aromatic to aliphatic ratio in ALH 84001 all correspond to low H/C and high CO/CO2 ratios in magmatic and impact gases and can be used to deduce spatial variations of these ratios. Some hydrocarbons could have been formed from trapped magmatic gases, especially if the cooling was fast enough to prevent reequilibration. We propose that subsequent impact heating(s) in ALH 84001 could have led to dissociation of ferrous carbonates to yield fine-grain magnetite, formation of a CO-rich local gas phase, reduction of water vapor to H2, reequilibration of the trapped magmatic gases, aromatization of hydrocarbons formed previously, and overprinting of the synthesis from magmatic gases, if any. Rapid cooling and high-temperature quenching of CO-, H2-rich impact gases could have led to magnetite-catalyzed hydrocarbon synthesis.

  3. An abiotic origin for hydrocarbons in the Allan Hills 84001 martian meteorite through cooling of magmatic and impact-generated gases

    NASA Technical Reports Server (NTRS)

    Shock, E. L.

    2000-01-01

    Thermodynamic calculations of metastable equilibria were used to evaluate the potential for abiotic synthesis of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in the martian meteorite Allan Hills (ALH) 84001. The calculations show that PAHs and normal alkanes could form metastably from CO, CO2, and H2 below approximately 250-300 degrees C during rapid cooling of trapped magmatic or impact-generated gases. Depending on temperature, bulk composition, and oxidation-reduction conditions, PAHs and normal alkanes can form simultaneously or separately. Moreover, PAHs can form at lower H/C ratios, higher CO/CO2 ratios, and higher temperatures than normal alkanes. Dry conditions with H/C ratios less than approximately 0.01-0.001 together with high CO/CO2 ratios also favor the formation of unalkylated PAHs. The observed abundance of PAHs, their low alkylation, and a variable but high aromatic to aliphatic ratio in ALH 84001 all correspond to low H/C and high CO/CO2 ratios in magmatic and impact gases and can be used to deduce spatial variations of these ratios. Some hydrocarbons could have been formed from trapped magmatic gases, especially if the cooling was fast enough to prevent reequilibration. We propose that subsequent impact heating(s) in ALH 84001 could have led to dissociation of ferrous carbonates to yield fine-grain magnetite, formation of a CO-rich local gas phase, reduction of water vapor to H2, reequilibration of the trapped magmatic gases, aromatization of hydrocarbons formed previously, and overprinting of the synthesis from magmatic gases, if any. Rapid cooling and high-temperature quenching of CO-, H2-rich impact gases could have led to magnetite-catalyzed hydrocarbon synthesis.

  4. Heterogeneous Ice Nucleation by Soufriere Hills Volcanic Ash Immersed in Water Droplets.

    PubMed

    Mangan, T P; Atkinson, J D; Neuberg, J W; O'Sullivan, D; Wilson, T W; Whale, T F; Neve, L; Umo, N S; Malkin, T L; Murray, B J

    2017-01-01

    Fine particles of ash emitted during volcanic eruptions may sporadically influence cloud properties on a regional or global scale as well as influencing the dynamics of volcanic clouds and the subsequent dispersion of volcanic aerosol and gases. It has been shown that volcanic ash can trigger ice nucleation, but ash from relatively few volcanoes has been studied for its ice nucleating ability. In this study we quantify the efficiency with which ash from the Soufriere Hills volcano on Montserrat nucleates ice when immersed in supercooled water droplets. Using an ash sample from the 11th February 2010 eruption, we report ice nucleating efficiencies from 246 to 265 K. This wide range of temperatures was achieved using two separate droplet freezing instruments, one employing nanolitre droplets, the other using microlitre droplets. Soufriere Hills volcanic ash was significantly more efficient than all other ash samples that have been previously examined. At present the reasons for these differences are not understood, but may be related to mineralogy, amorphous content and surface chemistry.

  5. Heterogeneous Ice Nucleation by Soufriere Hills Volcanic Ash Immersed in Water Droplets

    PubMed Central

    Atkinson, J. D.; Neuberg, J. W.; O’Sullivan, D.; Wilson, T. W.; Whale, T. F.; Neve, L.; Umo, N. S.; Malkin, T. L.; Murray, B. J.

    2017-01-01

    Fine particles of ash emitted during volcanic eruptions may sporadically influence cloud properties on a regional or global scale as well as influencing the dynamics of volcanic clouds and the subsequent dispersion of volcanic aerosol and gases. It has been shown that volcanic ash can trigger ice nucleation, but ash from relatively few volcanoes has been studied for its ice nucleating ability. In this study we quantify the efficiency with which ash from the Soufriere Hills volcano on Montserrat nucleates ice when immersed in supercooled water droplets. Using an ash sample from the 11th February 2010 eruption, we report ice nucleating efficiencies from 246 to 265 K. This wide range of temperatures was achieved using two separate droplet freezing instruments, one employing nanolitre droplets, the other using microlitre droplets. Soufriere Hills volcanic ash was significantly more efficient than all other ash samples that have been previously examined. At present the reasons for these differences are not understood, but may be related to mineralogy, amorphous content and surface chemistry. PMID:28056077

  6. Assessing the continuity of the blue ice climate record at Patriot Hills, Horseshoe Valley, West Antarctica

    NASA Astrophysics Data System (ADS)

    Winter, Kate; Woodward, John; Dunning, Stuart A.; Turney, Chris S. M.; Fogwill, Christopher J.; Hein, Andrew S.; Golledge, Nicholas R.; Bingham, Robert G.; Marrero, Shasta M.; Sugden, David E.; Ross, Neil

    2016-03-01

    We use high-resolution ground-penetrating radar (GPR) to assess the continuity of the Blue Ice Area (BIA) horizontal climate record at Patriot Hills, Horseshoe Valley, West Antarctica. The sequence contains three pronounced changes in deuterium isotopic values at ~18 cal ka, ~12 cal ka, and ~8 cal ka. GPR surveys along the climate sequence reveal continuous, conformable dipping isochrones, separated by two unconformities in the isochrone layers, which correlate with the two older deuterium shifts. We interpret these unconformities as discontinuities in the sequence, rather than direct measures of climate change. Ice sheet models and Internal Layer Continuity Index plots suggest that the unconformities represent periods of erosion occurring, as the former ice surface was scoured by katabatic winds in front of mountains at the head of Horseshoe Valley. This study demonstrates the importance of high-resolution GPR surveys for investigating both paleoflow dynamics and interpreting BIA climate records.

  7. Meteorites and Microbes: Meteorite Collection and Ice Sampling at Patriot Hills, Thiel Mountains, and South Pole, Antarctica

    NASA Technical Reports Server (NTRS)

    Sipiera, Paul P.; Hoover, Richard B.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    During the Antarctica 2000 Expedition, sponsored by the Planetary Studies Foundation, meteorites and ice microbiota were collected from the Patriot Hills, and Thiel Mountains of Antarctica and snow samples were at the South Pole. Psychrophilic and psychrotrophic microbiota were obtained from blue ice, cryoconite and ice-bubble systems. Twenty frozen meteorites were collected using aseptic techniques from the blue ice fields near the Moulton Escarpment of the Thiel Mountains (85 S, 94 W) and from the Morris Moraine of the Patriot Hills (80 S, 81 W) Ellsworth Mountains. These ice and meteorite samples are of potential significance to Astrobiology. They may help refine chemical and morphological biomarkers and refine characteristics of microbial life in one of the harshest environments on Earth. We discuss the Antarctica 2000 Expedition and provide preliminary results of the investigation of the meteorites and ice microbiota recovered.

  8. The Natural Thermoluminescence Survey of Antarctic Meteorites: Ordinary Chondrites at the Grosvenor Mountains, Macalpine Hills, Pecora Escarpment and Queen Alexandra Range, and New Data for the Elephant Moraine, Ice Fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Derek W. G.

    1999-01-01

    The natural TL (Thermoluminescence) survey of Antarctic meteorites was started in 1987 at the request of the Antarctic Meteorite Working Group in order to provide an initial description of radiation and thermal histories. It was intended to be a complement to the mineralogical and petrographic surveys performed at the Johnson Space Center and the Smithsonian Institution. All ANSMET (Antarctic Search for Meteorites) samples recovered since then, besides those that were heated throughout by atmospheric passage, have been measured. To date this amounts to about 1200 samples. As the data for each ice field reaches a significant level, we have been conducting a thorough examination of the data for that field with a view to identifying pairing, providing an estimate of terrestrial age and residence time on the ice surface, looking for differences in natural TL between ice fields, looking for variations in natural TL level with location on the ice, looking for meteorites with natural TL levels outside the normal range. Pairing is a necessary first step in ensuring the most productive use of the collection, while geographical variations could perhaps provide clues to concentration mechanisms. Samples with natural TL values outside the normal range are usually inferred to have had either small perihelia or recent changes in orbital elements. In addition, induced TL data have enabled us to look for evidence for secular variation in the nature of the flux of meteorites to Earth, and look for petrologically unusual meteorites, such as particularly primitive ordinary chondrites, heavily shocked meteorites, or otherwise anomalous meteorites. To date we have published studies of the TL properties of 167 ordinary chondrites from Allan Hills, 107 from Elephant Moraine and 302 from Lewis Cliff and we have discussed the TL properties of fifteen H chondrites collected at the Allan Hills by Euromet after a storm during the 1988 season. We now have additional databases for a reasonable

  9. The Natural Thermoluminescence Survey of Antarctic Meteorites: Ordinary Chondrites at the Grosvenor Mountains, MacAlpine Hills, Pecora Escarpment and Queen Alexandra Range, and New Data New Data for the Elephant Moraine, Ice Fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Derek W. G.

    2000-01-01

    The natural TL survey of Antarctic meteorites was started in 1987 at the request of the Antarctic Meteorite Working Group in order to provide an initial description of radiation and thermal histories. It was intended to be a complement to the mineralogical and petrographic surveys performed at the Johnson Space Center and the Smithsonian Institution. All ANSMET samples recovered since then, besides those that were heated throughout by atmospheric passage, have been measured. To date this amounts to about 1200 samples. As the data for each ice field reaches a significant level, we have been conducting a thorough examination of the data for that field with a view to (1) identifying pairing, (2) providing an estimate of terrestrial age and residence time on the ice surface, (3) looking for differences in natural TL between ice fields, (4) looking for variations in natural TL level with location on the ice, (5) looking for meteorites with natural TL levels outside the normal range. Pairing is a necessary first step in ensuring the @ost productive use of the collection, while geographical variations could perhaps provide clues to concentration mechanisms. Samples with natural TL values outside the normal range are usually inferred to have had either small perihelia or recent changes in orbital elements. In addition, induced TL data have enabled us to (5) look for evidence for secular variation in the nature of the flux of meteorites to Earth, and (6) look for petrologically unusual meteorites, such as particularly primitive ordinary chondrites, heavily shocked meteorites, or otherwise anomalous meteorites. To date we have published studies of the TL properties of 167 ordinary chondrites from Allan Hills, 107 from Elephant Moraine and 302 from Lewis Cliff and we have discussed the TL properties of fifteen H chondrites collected at the Allan Hills by Euromet after a storm during the 1988 season. We now have additional databases for a reasonable number of ordinary

  10. Sedimentology and geochemistry of a perennially ice-covered epishelf lake in Bunger Hills Oasis, East Antarctica

    NASA Technical Reports Server (NTRS)

    Doran, P. T.; Wharton, R. A. Jr; Lyons, W. B.; Des Marais, D. J.; Andersen, D. T.; Wharton RA, J. r. (Principal Investigator)

    2000-01-01

    A process-oriented study was carried out in White Smoke lake, Bunger Hills, East Antarctica, a perennially ice-covered (1.8 to 2.8 m thick) epishelf (tidally-forced) lake. The lake water has a low conductivity and is relatively well mixed. Sediments are transferred from the adjacent glacier to the lake when glacier ice surrounding the sediment is sublimated at the surface and replaced by accumulating ice from below. The lake bottom at the west end of the lake is mostly rocky with a scant sediment cover. The east end contains a thick sediment profile. Grain size and delta 13C increase with sediment depth, indicating a more proximal glacier in the past. Sedimentary 210Pb and 137Cs signals are exceptionally strong, probably a result of the focusing effect of the large glacial catchment area. The post-bomb and pre-bomb radiocarbon reservoirs are c. 725 14C yr and c. 1950 14C yr, respectively. Radiocarbon dating indicates that the east end of the lake is >3 ka BP, while photographic evidence and the absence of sediment cover indicate that the west end has formed only over the last century. Our results indicate that the southern ice edge of Bunger Hills has been relatively stable with only minor fluctuations (on the scale of hundreds of metres) over the last 3000 years.

  11. Sedimentology and geochemistry of a perennially ice-covered epishelf lake in Bunger Hills Oasis, East Antarctica.

    PubMed

    Doran, P T; Wharton, R A; Lyons, W B; Des Marais, D J; Andersen, D T

    2000-01-01

    A process-oriented study was carried out in White Smoke lake, Bunger Hills, East Antarctica, a perennially ice-covered (1.8 to 2.8 m thick) epishelf (tidally-forced) lake. The lake water has a low conductivity and is relatively well mixed. Sediments are transferred from the adjacent glacier to the lake when glacier ice surrounding the sediment is sublimated at the surface and replaced by accumulating ice from below. The lake bottom at the west end of the lake is mostly rocky with a scant sediment cover. The east end contains a thick sediment profile. Grain size and delta 13C increase with sediment depth, indicating a more proximal glacier in the past. Sedimentary 210Pb and 137Cs signals are exceptionally strong, probably a result of the focusing effect of the large glacial catchment area. The post-bomb and pre-bomb radiocarbon reservoirs are c. 725 14C yr and c. 1950 14C yr, respectively. Radiocarbon dating indicates that the east end of the lake is >3 ka BP, while photographic evidence and the absence of sediment cover indicate that the west end has formed only over the last century. Our results indicate that the southern ice edge of Bunger Hills has been relatively stable with only minor fluctuations (on the scale of hundreds of metres) over the last 3000 years.

  12. Measurements of Cl-36 in Antarctic meteorites and Antarctic ice using a Van de Graaff accelerator

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Arnold, J. R.; Finkel, R. C.; Elmore, D.; Ferraro, R. D.; Gove, H. E.; Beukens, R. P.; Chang, K. H.; Kilius, L. R.

    1979-01-01

    The paper presents measurements of cosmic-ray produced (Cl-36) in Antarctic meteorites and ice using a Van de Graaff accelerator as an ultrasensitive mass spectrometer. Results from this ion counting technique are used to support a two-stage irradiation model for the Yamato-7301 and Allan Hills-76008 meteorites and to show a long terrestrial age for Allan Hills-77002. Yamato-7304 has a terrestrial age of less than 0.1 m.y., and the (Cl-36) content of the Antarctic ice sample from the Yamato mountain is consistent with levels expected in currently depositing snow implying that the age of the ice cap at this site is less than on (Cl-36) half-life.

  13. Meteorite infall as a function of mass - Implications for the accumulation of meteorites on Antarctic ice

    NASA Technical Reports Server (NTRS)

    Huss, Gary R.

    1990-01-01

    Antarctic meteorites are considerably smaller, on average, than those recovered elsewhere in the world, and seem to represent a different portion of the mass distribution of infalling meteorites. When an infall rate appropriate to the size of Antarctic meteorites is used (1000 meteorites 10 grams or larger/sq km/1 million years), it is found that direct infall can produce the meteorite accumulations found on eight ice fields in the Allan Hills region in times ranging from a few thousand to nearly 200,000 years, with all but the Allan Hills Main and Near Western ice fields requiring less than 30,000 years. Meteorites incorporated into the ice over time are concentrated on the surface when the ice flows into a local area of rapid ablation. The calculated accumulation times, which can be considered the average age of the exposed ice, agree well with terrestrial ages for the meteorites and measured ages of exposed ice. Since vertical concentration of meteorites through removal of ice by ablation is sufficient to explain the observed meteorite accumulations, there is no need to invoke mechanisms to bring meteorites from large areas to the relatively small blue-ice patches where they are found. Once a meteorite is on a bare ice surface, freeze-thaw cycling and wind break down the meteorite and remove it from the ice. The weathering lifetime of a 100-gram meteorite on Antarctic ice is on the order of 10,000 + or - 5,000 years.

  14. The quantum Allan variance

    NASA Astrophysics Data System (ADS)

    Chabuda, Krzysztof; Leroux, Ian D.; Demkowicz-Dobrzański, Rafał

    2016-08-01

    The instability of an atomic clock is characterized by the Allan variance, a measure widely used to describe the noise of frequency standards. We provide an explicit method to find the ultimate bound on the Allan variance of an atomic clock in the most general scenario where N atoms are prepared in an arbitrarily entangled state and arbitrary measurement and feedback are allowed, including those exploiting coherences between succeeding interrogation steps. While the method is rigorous and general, it becomes numerically challenging for large N and long averaging times.

  15. The Stability of the West Antarctic Ice Sheet During the Last Interglacial (127-110 ka): A New Record From the Patriot Hills

    NASA Astrophysics Data System (ADS)

    Turney, C. S.; Fogwill, C. J.; Etheridge, D. M.; Bird, M. I.; Rubino, M.; Thornton, D.; Munksgaard, N.; Cooper, A.; Millman, H.; Rootes, C.; Rivera, A.; Baker, A.; Weyrich, L.

    2015-12-01

    The Last Interglacial (LIG; ca. 127 - 110 ka) is increasingly being investigated as a possible analogue for future climate change. Quantified estimates of LIG temperatures suggest global mean temperatures were approximately 2˚C warmer than the pre-industrial period, similar to the RCP2.6 scenario for the end of the twenty-first century. Importantly this period is associated with a global sea level between 6.6 and 9.4 m higher than present day, of which a significant component most probably derived from Antarctica. However, the contribution from the marine-based West Antarctic Ice Sheet (WAIS) remains highly uncertain. To investigate the stability of the WAIS we report new results from the Patriot Hills blue ice area, located close to the modern day grounding line of the Institute Ice Stream in the Weddell Sea Embayment. A multi proxy study of the ice (including water stable isotopes and atmospheric gas concentrations) provides a unique record of changing WAIS extent over the last glacial-interglacial cycle. We present evidence for the presence of LIG ice at Patriot Hills and discuss the implications for Antarctic ice sheet stability and global sea level rise during super-interglacials.

  16. Spectral Ambiguity of Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, C. A.

    1996-01-01

    We study the extent to which knowledge of Allan variance and other finite-difference variances determines the spectrum of a random process. The variance of first differences is known to determine the spectrum. We show that, in general, the Allan variance does not. A complete description of the ambiguity is given.

  17. Autonomy Software Architecture for LORAX (Life On ice Robotic Antarctic eXplorer)

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari; McGann, Conor; Pedersen, Liam; Iatauro, Michael; Rajagopalan, Srikanth

    2005-01-01

    LORAX is a robotic astrobiological study of the ice field surrounding the Carapace Nunatak near the Allan Hills in Antarctica. The study culminates in a l00km traverse, sampling the ice at various depths (from surface to 10cm) at over 100 sites to survey microbial ecology and to record environmental parameters. The autonomy requirements from LORAX are shared by many robotic exploration tasks. Consequently, the LORAX autonomy architecture is a general architecture for on-board planning and execution in environments where science return is to be maximized against resource limitations and other constraints.

  18. Meteoritic event recorded in Antarctic ice

    SciTech Connect

    Harvey, R.P.; Dunbar, N.W.; McIntosh, W.C.; Esser, R.P.; Nishiizumi, Kuni; Taylor, S.; Caffee, M.W.

    1998-07-01

    During systematic sampling of volcanic ash (tephra) layers at a well-known Antarctic meteorite collection site (the Allan Hills main ice field), a band of unusually dark and rounded (many spheroidal) particles was discovered. This debris layer (BIT-58) extends parallel to the stratigraphy of the ice established from the tephra bands, apparently marking a single depositional event. The shapes, internal texture, major element composition, and levels of cosmogenic nuclides of particles from within BIT-58 all strongly suggest that this material represents ablation debris from the passage of a large H-group ordinary chondrite. Preliminary cosmogenic isotope dating suggests an age of 2.8 Ma, implying that the East Antarctic ice sheet has been stable since that time. The relationship of the Bit-58 layer to known impact events is not clear.

  19. Cosmogenic 10Be ages from the Meirs and Garwood Valleys, Denton Hills, West Antarctica, suggest an absence in LGM Ice Sheet expansion.

    NASA Astrophysics Data System (ADS)

    Fink, David; Joy, Kurt; Storey, Bryan

    2014-05-01

    It has been hypothesised that during interglacials, thinning of the Ross Ice Shelf allowed a more open water environment with increased local precipitation. This resulted in outlet glaciers, which drain the Transantarctic Mountains and fed by the East Antarctic Ice Sheet, advancing during moist warmer periods, apparently out of phase with colder arid dry periods. Significantly the ice core record during these warm periods also shows increased accumulation continent wide The geomorphology of the Denton Hills in the Royal Society Range, West Antarctica, is a result of Miocene fluvial incision reworked by subsequent glacial advances throughout the Quaternary. The Garwood and Miers glacial valleys drain ice across the Denton Hills into the Shelf, and should thus show maximum extent during interstadials. To understand the chronology of late Quaternary glaciations, 15 granitic boulders from terminal moraines were sampled for 10Be and 26Al cosmogenic dating. Obtaining reliable exposure ages of erratics within moraines that represent timing of deposition (i.e. glacial advances) is problematic in polar regions, where glacial activity is principally controlled by ice sheet dynamics. Recycling of previously exposed debris, uncertainty in provenance of glacially transported boulders and a lack of a post-depositional hydrologic process to remove previously exposed material from a valley system, leads to ambiguities in multiple exposure ages from a single coeval glacial landform. More importantly, cold-based ice advance can leave a landform unmodified resulting in young erratics deposited on bedrock that shows weathering and/or inconsistent age-altitude relationships. Primarily, inheritance becomes a difficulty in qualifying exposure ages from polar regions. Preliminary results from the Garwood and Miers Valleys indicate that glaciers in the Denton Hills had begun to retreat from their last maximum positions no later than 23-37 ka, and thus the local last glacial maximum

  20. From IDs to Ice Cream to "I, Claudius": Security Is in the Cards at Cleveland Hill Union Free School District.

    ERIC Educational Resources Information Center

    Passmore, Cheryl

    2002-01-01

    Describes the use of plastic identity badges with photographs and barcodes issued to all administrators, teachers, staff members, and students in grades 6-12 at the Cleveland Hill Union Free School District in Cheektowaga, New York. (PKP)

  1. Allan Cox 1926”1987

    NASA Astrophysics Data System (ADS)

    Coe, Rob; Dalrymple, Brent

    More than 1000 friends, students, and colleagues from all over the country filled Stanford Memorial Chapel (Stanford, Calif.) on February 3, 1987, to join in “A Celebration of the Life of Allan Cox.” Allan died early on the morning of January 27 while bicycling, the sport he had come to love the most. Between pieces of his favorite music by Bach and Mozart, Stanford administrators and colleagues spoke in tribute of Allan's unique qualities as friend, scientist, teacher, and dean of the School of Earth Sciences. James Rosse, Vice President and Provost of Stanford University, struck a particularly resonant chord with his personal remarks: "Allan reached out to each person he knew with the warmth and attention that can only come from deep respect and affection for others. I never heard him speak ill of others, and I do not believe he was capable of doing anything that would harm another being. He cared too much to intrude where he was not wanted, but his curiosity about people and the loving care with which he approached them broke down reserve to create remarkable friendships. His enthusiasm and good humor made him a welcome guest in the hearts of the hundreds of students and colleagues who shared the opportunity of knowing Allan Cox as a person."

  2. Edgar Allan Poe and neurology.

    PubMed

    Teive, Hélio Afonso Ghizoni; Paola, Luciano de; Munhoz, Renato Puppi

    2014-06-01

    Edgar Allan Poe was one of the most celebrated writers of all time. He published several masterpieces, some of which include references to neurological diseases. Poe suffered from recurrent depression, suggesting a bipolar disorder, as well as alcohol and drug abuse, which in fact led to his death from complications related to alcoholism. Various hypotheses were put forward, including Wernicke's encephalopathy.

  3. Allan Bloom, America, and Education.

    ERIC Educational Resources Information Center

    West, Thomas

    2000-01-01

    Refutes the claims of Allan Bloom that the source of the problem with today's universities is modern philosophy, that the writings and ideas of Hobbes and Locke planted the seeds of relativism in American culture, and that the cure is Great Books education. Suggests instead that America's founding principles are the only solution to the failure of…

  4. Allan Bloom's Quarrel with History.

    ERIC Educational Resources Information Center

    Thompson, James

    1988-01-01

    Responds to Allan Bloom's "The Closing of the American Mind." Concludes that despite cranky comments about bourgeois culture, the focus of Bloom's attack is on historicism, which undercuts his nostalgic vision of a prosperous and just America. Condemns Bloom's exclusion of Blacks, Hispanics, and women from America's cultural heritage.…

  5. Allan Hills 12073: A Metal-Rich Eucrite

    NASA Astrophysics Data System (ADS)

    Di Rocco, T.; Nava, J.; Gemelli, M.; D'Orazio, M.; Domeneghetti, M. C.; Alvaro, M.; Pack, A.; Folco, L.

    2016-08-01

    We report on the petrology and geochemistry of the metal rich eucrite ALH 12073. The high metal and bulk siderophile element content are anomalous for eucrites and needs explanations. Several hypothesis will be discussed.

  6. Mineral Biomarkers in Martian Meteorite Allan Hills 84001?

    NASA Technical Reports Server (NTRS)

    Thomas-Keprta, K. L.; Bazylinski, D. A.; Wentworth, S. J.; McKay, D. S.; Golden, D. C.; Gibson, E. K., Jr.; Romanek, C. S.

    1998-01-01

    The occurrence of fine-grained magnetite in the Fe-rich rims surrounding carbonate globules in the martian meteorite ALH84001, originally described in , have been proposed as fossil remains of primitive martian organisms. Here we report observations on size and shape distributions of magnetites from ALH84001 and compare them to biogenic and inorganic magnetite crystals of terrestrial origin. While some magnetite morphology is not unequivocally diagnostic for its biogenicity, such as cubodial forms of magnetite, which are common in inorganically formed magnetites, other morphologies of magnetite (parallel-epiped or elongated prismatic and arrowhead forms) are more likely signatures of biogenic activity. Some ALH 84001 magnetite particles described below have unique morphology and length-to-width ratios that are indistinguishable from a variety of terrestrial biogenic magnetite and distinct from all known inorganic forms of magnetite.

  7. Allan Hills A77219 - The first Antarctic mesosiderite

    NASA Technical Reports Server (NTRS)

    Agosto, W. N.; Hewins, R. H.; Clarke, R. S., Jr.

    1980-01-01

    The abundance of orthopyroxene, inverted pigeonite, plagioclase, tridymite, kamacite, and tetrataenite, plus the whole rock analysis, indicates that ALHA 77219 is a mesosiderite. The presence of inverted pigeonite rims on orthopyroxene clasts plus the range of Fe/Mg and Fe/Mn ratios for pyroxene and olivine are characteristic of mesosiderites. All the petrographic and chemical data are consistent with classification of ALHA 77219 as a mesosiderite and, because the matrix is fine-grained and little recrystallized, as a subgroup I mesosiderite. The Fe/Mn trends in pyroxenes of mesosiderites such as ALHA 77219 can be explained by igneous fractionation of pyroxene along with metal and subsequent subsolidus reduction in the breccia.

  8. Rubidium-Strontium Formation Age of Allan Hills 84001 Carbonates

    NASA Technical Reports Server (NTRS)

    Borg, L. E.; Nyquist, L. E.; Shih, C.-Y.; Weismann, H.; Reese, Y.; Connelly, J. N.

    1998-01-01

    Our preferred age for the formation of carbonates in the martian meteorite ALH 84001 is 3.90 plus or minus 0.04 Ga for Lambda (Rubidium 87) equals 0.01402 Ga (exp -1), or 3.85 plus or minus 0.04 Ga for Lambda (Rubidium 87) = 0.0142 Ga(exponent -1). This age is determined by a three-point Rb-Sr isochron defined by leachates of high-graded carbonate-rich material. Major cation and especially phosphorous analyses of the leachates permit contributions from igneous whitlockite to be recognized for low-acidity leachates, and the corresponding data are omitted from the isochron. Data for the two highest acidity leachates plot close to the preferred isochron, but are omitted because we believe they contain contributions leached from the pyroxene substrate on which most of the carbonates are found. Nevertheless, the isochron age for all five highest-acidity leachates is 3.94 plus or minus 0.04 Ga, and is within error of the age obtained for the more restricted data set. All leachates used to define the isochron have major cation compositions that are singular to those obtained by microprobe analyses of the carbonate rosettes and are consistent with progressive digestion of the carbonates according to their composition. The age thus obtained for the carbonates is about 600 m.y. younger than the crystalization age of ALH 84001 determined by Sm-Nd analyses but is within error limits of the age of impact metamorphism inferred from the Rb-Sr and Ar-Ar systematics of silicates. which yield ages of 3.85 plus or minus 0.05 Ga and 4.05- 3.80 Ga to 4.3-3.8 Ga, respectively. Similarities between the carbonate crystallization age and the age of impact metamorphism as determined by Ar-Ar and Rb-Sr suggest that the carbonate formation is impact-related. Nevertheless, both high and low- temperature scenarios for the origin of the carbonates are possible.

  9. Estimating the Modified Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, Charles

    1995-01-01

    The third-difference approach to modified Allan variance (MVAR) leads to a tractable formula for a measure of MVAR estimator confidence, the equivalent degrees of freedom (edf), in the presence of power-law phase noise. The effect of estimation stride on edf is tabulated. A simple approximation for edf is given, and its errors are tabulated. A theorem allowing conservative estimates of edf in the presence of compound noise processes is given.

  10. A Wavelet Perspective on the Allan Variance.

    PubMed

    Percival, Donald B

    2016-04-01

    The origins of the Allan variance trace back 50 years ago to two seminal papers, one by Allan (1966) and the other by Barnes (1966). Since then, the Allan variance has played a leading role in the characterization of high-performance time and frequency standards. Wavelets first arose in the early 1980s in the geophysical literature, and the discrete wavelet transform (DWT) became prominent in the late 1980s in the signal processing literature. Flandrin (1992) briefly documented a connection between the Allan variance and a wavelet transform based upon the Haar wavelet. Percival and Guttorp (1994) noted that one popular estimator of the Allan variance-the maximal overlap estimator-can be interpreted in terms of a version of the DWT now widely referred to as the maximal overlap DWT (MODWT). In particular, when the MODWT is based on the Haar wavelet, the variance of the resulting wavelet coefficients-the wavelet variance-is identical to the Allan variance when the latter is multiplied by one-half. The theory behind the wavelet variance can thus deepen our understanding of the Allan variance. In this paper, we review basic wavelet variance theory with an emphasis on the Haar-based wavelet variance and its connection to the Allan variance. We then note that estimation theory for the wavelet variance offers a means of constructing asymptotically correct confidence intervals (CIs) for the Allan variance without reverting to the common practice of specifying a power-law noise type a priori. We also review recent work on specialized estimators of the wavelet variance that are of interest when some observations are missing (gappy data) or in the presence of contamination (rogue observations or outliers). It is a simple matter to adapt these estimators to become estimators of the Allan variance. Finally we note that wavelet variances based upon wavelets other than the Haar offer interesting generalizations of the Allan variance.

  11. Sublimation: A Mechanism for the Enrichment of Organics in Antarctic Ice

    NASA Technical Reports Server (NTRS)

    Becker, Luann; McDonald, Gene D.; Glavin, Daniel P.; Bada, Jeffrey L.; Bunch, Theodore E.; Chang, Sherwood (Technical Monitor)

    1997-01-01

    Recent analyses of the carbonate globules present in the Martian meteorite ALH84001 have detected polycyclic aromatic hydrocarbons (PAHs) at the ppm level. The distribution of PAHs observed in ALH84001 was interpreted as being inconsistent with a terrestrial origin and were claimed to be indigenous to the meteorite, perhaps derived from an ancient Martian biota. However, Becker et al., have examined PAHs in the Martian meteorite EETA79001, in several Antarctic carbonaceous chondrites and Antarctic Allan Hills Ice and detected many of the same PAHs found in ALH84001. The reported presence of L-amino acids of apparent terrestrial origin in the EETA79001 druse material, suggests that this meteorite is contaminated with terrestrial/extraterrestrial organics probably derived from Antarctic ice meltwater that had percolated through the meteorite. The detection of PAHs and L-amino acids in these Martian meteorites suggests that despite storage in the Antarctic ice, selective changes of certain chemical and mineralogical phases has occurred.

  12. Estimating the Modified Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, Charles

    1995-01-01

    A paper at the 1992 FCS showed how to express the modified Allan variance (mvar) in terms of the third difference of the cumulative sum of time residuals. Although this reformulated definition was presented merely as a computational trick for simplifying the calculation of mvar estimates, it has since turned out to be a powerful theoretical tool for deriving the statistical quality of those estimates in terms of their equivalent degrees of freedom (edf), defined for an estimator V by edf V = 2(EV)2/(var V). Confidence intervals for mvar can then be constructed from levels of the appropriate 2 distribution.

  13. Hill In Deuteronilus

    NASA Technical Reports Server (NTRS)

    2004-01-01

    28 December 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an eroded, rounded hill in the Deuteronilus Colles region of Mars, near 40.3oN, 338.8oW. The plains surrounding the hill have been pitted and modified by erosion. Similar pitting is common throughout the middle latitude regions of Mars. Some Mars science investigators have proposed that the pitted materials were ice-rich, and that sublimation of ice has created these textures. However, no similar landforms are found on Earth, thus there is no clear analog that would help scientists better understand the origin of these features. The picture covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the left/lower left.

  14. Edgar Allan Poe's Physical Cosmology

    NASA Astrophysics Data System (ADS)

    Cappi, Alberto

    1994-06-01

    In this paper I describe the scientific content of Eureka, the prose poem written by Edgar Allan Poe in 1848. In that work, starting from metaphysical assumptions, Poe claims that the Universe is finite in an infinite Space, and that it was originated from a primordial Particle, whose fragmentation under the action of a repulsive force caused a diffusion of atoms in space. I will show that his subsequently collapsing universe represents a scientifically acceptable Newtonian model. In the framework of his evolving universe, Poe makes use of contemporary astronomical knowledge, deriving modern concepts such as a primordial atomic state of the universe and a common epoch of galaxy formation. Harrison found in Eureka the first, qualitative solution of the Olbers' paradox; I show that Poe also applies in a modern way the anthropic principle, trying to explain why the Universe is so large.

  15. Possible Meteorites in the Martian Hills

    NASA Technical Reports Server (NTRS)

    2006-01-01

    From its winter outpost at 'Low Ridge' inside Gusev Crater, NASA's Mars Exploration Rover Spirit took this spectacular, color mosaic of hilly, sandy terrain and two potential iron meteorites. The two light-colored, smooth rocks about two-thirds of the way up from the bottom of the frame have been labeled 'Zhong Shan' and 'Allan Hills.'

    The two rocks' informal names are in keeping with the rover science team's campaign to nickname rocks and soils in the area after locations in Antarctica. Zhong Shang is an Antarctic base that the People's Republic of China opened on Feb. 26, 1989, at the Larsemann Hills in Prydz Bay in East Antarctica. Allan Hills is a location where researchers have found many Martian meteorites, including the controversial ALH84001, which achieved fame in 1996 when NASA scientists suggested that it might contain evidence for fossilized extraterrestrial life. Zhong Shan was the given name of Dr. Sun Yat-sen (1866-1925), known as the 'Father of Modern China.' Born to a peasant family in Guangdong, Sun moved to live with his brother in Honolulu at age 13 and later became a medical doctor. He led a series of uprisings against the Qing dynasty that began in 1894 and eventually succeeded in 1911. Sun served as the first provisional president when the Republic of China was founded in 1912.

    The Zhong Shan and Allan Hills rocks, at the left and right, respectively, have unusual morphologies and miniature thermal emission spectrometer signatures that resemble those of a rock known as 'Heat Shield' at the Meridiani site explored by Spirit's twin, Opportunity. Opportunity's analyses revealed Heat Shield to be an iron meteorite.

    Spirit acquired this approximately true-color image on the rover's 872nd Martian day, or sol (June 16, 2006), using exposures taken through three of the panoramic camera's filters, centered on wavelengths of 600 nanometers, 530 nanometers, and 480 nanometers.

  16. Red Hill

    EPA Pesticide Factsheets

    Information about the Red Hill Bulk Fuel Storage Facility in Hawaii Administrative Order on Consent (AOC), an enforceable agreement of the Hawaii Department of Health, the Environmental Protection Agency, and the U.S. Navy -- Defense Logistics Agency.

  17. Friis Hills Drilling Project - Coring an Early to mid-Miocene terrestrial sequence in the Transantarctic Mountains to examine climate gradients and ice sheet variability along an inland-to-offshore transect

    NASA Astrophysics Data System (ADS)

    Lewis, A. R.; Levy, R. H.; Naish, T.; Gorman, A. R.; Golledge, N.; Dickinson, W. W.; Kraus, C.; Florindo, F.; Ashworth, A. C.; Pyne, A.; Kingan, T.

    2015-12-01

    The Early to mid-Miocene is a compelling interval to study Antarctic ice sheet (AIS) sensitivity. Circulation patterns in the southern hemisphere were broadly similar to present and reconstructed atmospheric CO2 concentrations were analogous to those projected for the next several decades. Geologic records from locations proximal to the AIS are required to examine ice sheet response to climate variability during this time. Coastal and offshore drill core records recovered by ANDRILL and IODP provide information regarding ice sheet variability along and beyond the coastal margin but they cannot constrain the extent of inland retreat. Additional environmental data from the continental interior is required to constrain the magnitude of ice sheet variability and inform numerical ice sheet models. The only well-dated terrestrial deposits that register early to mid-Miocene interior ice extent and climate are in the Friis Hills, 80 km inland. The deposits record multiple glacial-interglacial cycles and fossiliferous non-glacial beds show that interglacial climate was warm enough for a diverse biota. Drifts are preserved in a shallow valley with the oldest beds exposed along the edges where they terminate at sharp erosional margins. These margins reveal drifts in short stratigraphic sections but none is more than 13 m thick. A 34 m-thick composite stratigraphic sequence has been produced from exposed drift sequences but correlating beds in scattered exposures is problematic. Moreover, much of the sequence is buried and inaccessible in the basin center. New seismic data collected during 2014 reveal a sequence of sediments at least 50 m thick. This stratigraphic package likely preserves a detailed and more complete sedimentary sequence for the Friis Hills that can be used to refine and augment the outcrop-based composite stratigraphy. We aim to drill through this sequence using a helicopter-transportable diamond coring system. These new cores will allow us to obtain

  18. John A. Scigliano Interviews Allan B. Ellis.

    ERIC Educational Resources Information Center

    Scigliano, John A.

    2000-01-01

    This interview with Allan Ellis focuses on a history of computer applications in education. Highlights include work at the Harvard Graduate School of Education; the New England Education Data System; and efforts to create a computer-based distance learning and development program called ISVD (Information System for Vocational Decisions). (LRW)

  19. [The medical history of Edgar Allan Poe].

    PubMed

    Miranda C, Marcelo

    2007-09-01

    Edgar Allan Poe, one of the best American storytellers and poets, suffered an episodic behaviour disorder partially triggered by alcohol and opiate use. Much confusion still exists about the last days of his turbulent life and the cause of his death at an early age. Different etiologies have been proposed to explain his main medical problem, however, complex partial seizures triggered by alcohol, poorly recognized at the time when Poe lived, seems to be one of the most acceptable hypothesis, among others discussed.

  20. The Cosmology of Edgar Allan Poe

    NASA Astrophysics Data System (ADS)

    Cappi, Alberto

    2011-06-01

    Eureka is a ``prose poem'' published in 1848, where Edgar Allan Poe presents his original cosmology. While starting from metaphysical assumptions, Poe develops an evolving Newtonian model of the Universe which has many and non casual analogies with modern cosmology. Poe was well informed about astronomical and physical discoveries, and he was influenced by both contemporary science and ancient ideas. For these reasons, Eureka is a unique synthesis of metaphysics, art and science.

  1. Thermoluminescence Measurements on Meteorites from the Elephant Moraine Region: L6 Showers and Regional Ice Movements

    NASA Astrophysics Data System (ADS)

    Benoit, P. H.; Sears, D. W. G.

    1992-07-01

    As part of their initial characterization, we have completed natural and induced thermoluminescence (TL) measurements for over 800 Antarctic meteorites. We have previously discussed the implications of these data for pairing, terrestrial age, and meteorite concentration mechanism at the Lewis Cliff and Allan Hills sites (Benoit et al., 1992a,b). Here we report data for meteorites from the Elephant Moraine region (designated EET, see Huss, 1990, for description of region). Our present discussion is limited to meteorites collected in the 1986/87 and 1987/88 field seasons; measurement of samples from the 1990/91 field season are underway. The Elephant Moraine region encompasses at least five meteorite-bearing blue icefields, including Elephant Moraine proper (EM), Meteorite City (MC), Upper Meteorite City (UMC), Texas Bowl (TB), and the Northern Ice Patch (NIP). While MC, UMC, and TB are physically adjacent to each other, EM and NIP are separated from the others, the latter being approximately 40 km distant from UMC. We have previously identified numerous pairing groups within the EET database without regard for field location. While most pairing groups are found to be restricted to single fields, there are a significant number that span several fields. The howardite group EET87503 covers both TB and EM and several L6 groups either span TB and EM or span the physically adjacent TB, UMC, and MC icefields. Even the isolated NIP apparently shares a few pairing groups with UMC and TB, although the small number of samples from this field make comparison difficult. This result seems to indicate that, unlike the Allan Hills sites, the individual ice fields at EET are sampling the same meteorite population. Natural TL levels for EET meteorites (Fig. 1) are generally high, with a significant fraction having TL levels greater than 50 krad. This would suggest that, in general, these meteorites have small terrestrial ages, probably <100,000 years for most meteorites. In this

  2. Refining LA-ICP-MS techniques for the exploration of ultra-thin layers in Alpine and Polar ice

    NASA Astrophysics Data System (ADS)

    Spaulding, Nicole; Bohleber, Pascal; Mayewski, Paul; Wagenbach, Dietmar; Kurbatov, Andrei; Sneed, Sharon; Handley, Mike; Erhardt, Tobias

    2015-04-01

    origin, archived in the CG ice core. Considering more broadly our findings from the CG ice and the refined characterization of our LA system, this technique promises to be of great benefit to the analysis of ultra-thin ice core layers. This may be especially relevant for members of the ice core community pursuing million year old ice kilometers below the surface. As such we also provide examples of LA analysis of deep polar ice from Greenland (GISP2) and shallow, yet ancient (up to 1 Mya), ice from the Allan Hills Blue Ice Area, Antarctica, which demonstrate how the insight gained from our study could be applied by the polar ice coring community.

  3. 32. SCIENTISTS ALLAN COX (SEATED), RICHARD DOELL, AND BRENT DALRYMPLE ...

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

    32. SCIENTISTS ALLAN COX (SEATED), RICHARD DOELL, AND BRENT DALRYMPLE AT CONTROL PANEL, ABOUT 1965. - U.S. Geological Survey, Rock Magnetics Laboratory, 345 Middlefield Road, Menlo Park, San Mateo County, CA

  4. Possible Meteorites in the Martian Hills (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    From its winter outpost at 'Low Ridge' inside Gusev Crater, NASA's Mars Exploration Rover Spirit took this spectacular, color mosaic of hilly, sandy terrain and two potential iron meteorites. The two light-colored, smooth rocks about two-thirds of the way up from the bottom of the frame have been labeled 'Zhong Shan' and 'Allan Hills.'

    The two rocks' informal names are in keeping with the rover science team's campaign to nickname rocks and soils in the area after locations in Antarctica. Zhong Shang is an Antarctic base that the People's Republic of China opened on Feb. 26, 1989, at the Larsemann Hills in Prydz Bay in East Antarctica. Allan Hills is a location where researchers have found many Martian meteorites, including the controversial ALH84001, which achieved fame in 1996 when NASA scientists suggested that it might contain evidence for fossilized extraterrestrial life. Zhong Shan was the given name of Dr. Sun Yat-sen (1866-1925), known as the 'Father of Modern China.' Born to a peasant family in Guangdong, Sun moved to live with his brother in Honolulu at age 13 and later became a medical doctor. He led a series of uprisings against the Qing dynasty that began in 1894 and eventually succeeded in 1911. Sun served as the first provisional president when the Republic of China was founded in 1912.

    The Zhong Shan and Allan Hills rocks, at the left and right, respectively, have unusual morphologies and miniature thermal emission spectrometer signatures that resemble those of a rock known as 'Heat Shield' at the Meridiani site explored by Spirit's twin, Opportunity. Opportunity's analyses revealed Heat Shield to be an iron meteorite.

    Spirit acquired this false-color image on the rover's 872nd Martian day, or sol (June 16, 2006), using exposures taken through three of the panoramic camera's filters, centered on wavelengths of 750 nanometers, 530 nanometers, and 430 nanometers. The image is presented in false color to emphasize differences among

  5. Rare Potassium-Bearing Mica in Allan Hills 84001: Additional Constraints on Carbonate Formation

    NASA Technical Reports Server (NTRS)

    Brearley, A. J.

    1998-01-01

    There have been presented several intriguing observations suggesting evidence of fossil life in martian orthopyroxenite ALH 84001. These exciting and controversial observations have stimulated extensive debate over the origin and history of ALH 84001, but many issues still remain unresolved. Among the most important is the question of the temperature at which the carbonates, which host the putative microfossils, formed. Oxygen- isotopic data, while showing that the carbonates are generally out of isotopic equilibria with the host rock, cannot constrain their temperature of formation. Both low- and high-temperature scenarios are plausible depending on whether carbonate growth occurred in an open or closed system. Petrographic arguments have generally been used to support a high-temperature origin but these appear to be suspect because they assume equilibrium between carbonate compositions that are not in contact. Some observations appear to be consistent with shock mobilization and growth from immiscible silicate-carbonate melts at high temperatures. Proponents of a low-temperature origin for the carbonates are hampered by the fact that there is currently no evidence of hydrous phases that would indicate low temperatures and the presence of a hydrous fluid during the formation of the carbonates. However, the absence of hydrous phases does not rule out carbonate formation at low temperatures, because the carbonate forming fluids may have been extremely CO2 rich, such that hydrous phases would not have been stabilized. In this study, I have carried out additional Transmission electron microscopy (TEM) studies of ALH-84001 and have found evidence of very rare phyllosilicates, which appear to be convincingly of pre-terrestrial origin. At present these observations are limited to one occurrence: further studies are in progress to determine if the phyllosilicates are more widespread.

  6. A note on the Allan Hills A77278 unequilibrated ordinary chondrite

    NASA Technical Reports Server (NTRS)

    Mcsween, H. Y., Jr.; Wilkening, L. L.

    1980-01-01

    Petrographic measures of disequilibrium in the ALHA 77278 chondrite indicate that this meteorite is more equilibrated than its exceptionally high volatile element contents suggest. Based on its metal compositions, this meteorite should be classified as an LL3 rather than an L3 chondrite.

  7. Siderophile, lithophile and mobile trace elements in the lunar meteorite Allan Hills 81005

    NASA Technical Reports Server (NTRS)

    Verkouteren, R. M.; Dennison, J. E.; Lipschutz, M. E.

    1983-01-01

    The content of trace elements (siderophile Co, Au, As, Sb, Ga; chalcophile/mobile Se, Te, Bi, In, Ag, Zn, Tl, Cd; lithophile Rb, Cs, U) is investigated to ascertain whether the meteorite is of lunar origin. Five elements reflect lunar crustal processes, whereas the remaining 11 siderophile and mobile elements suggest 1.4 + or - 0.5 percent micrometeorite admixture or enrichment by thermal redistribution on the moon. It is found that the impact launching of ALH A81005 to the earth was not attended by substantial shock loading. A Martian origin for severely shocked SNC meteorites is therefore considered plausible.

  8. Mineralogical aspects of terrestrial weathering effects in chondrites from Allan Hills, Antarctica

    NASA Technical Reports Server (NTRS)

    Gooding, J. L.

    1982-01-01

    The work reported here represents a first attempt at comparing the mineralogical aspects of weathering effects in selected Antarctic chondrites with those present in a petrologically similar chondrite which was weathered in the Arizona desert. The methods of analysis employed include X-ray diffractometry, differential thermal analysis, and reflectance spectrophotometry. It is found that the dominant weathering products in the rocks are complex, multiple-phase, hydrous ferric oxides which formed by alteration of Ni-Fe metal and sulfide particles under the influence of liquid water. The Fe-oxide weathering products may comprise approximately 15-20 wt % of the most intensely weathered samples although the same samples contain not more than 5% goethite as the only well-crystallized hydrous ferric oxide.

  9. Cumberland Falls chondritic inclusions. III - Consortium study of relationship to inclusions in Allan Hills 78113 aubrite

    NASA Technical Reports Server (NTRS)

    Lipschutz, Michael E.; Verkouteren, R. Michael; Sears, Derek W. G.; Hasan, Fouad A.; Prinz, Martin

    1988-01-01

    The contents of Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, Tl, U, and Zn in large chondritic clasts from the Cumbersand Falls aubrite were determined by radiochemical neutron activation analysis, and the results, together with the results of a mineralogical investigation, were compared with respective data obtained for three primitive inclusions from the ALH A78113 aubrite. The results indicated that the clasts from both aubrite sources constitute a single chondritic suite. The analyses data, together with the results of thermoluminescence data for Cumberland Falls chondritic inclusions and achondritic host, indicate that inclusions in Cumberland Falls and in ALH A78113 aubrite represent a primitive chondrite sample suite whose properties were established during primary nebular accretion and condensation over a broad redox range.

  10. Alteration Products and Secondary Minerals in Martian Meteorite Allan Hills 84001

    NASA Technical Reports Server (NTRS)

    Wentworth, S. J.; Thomas-Keprta, K. L.; McKay, D. S.

    1998-01-01

    The martian meteorites contain alteration products and secondary minerals that are a critical part of understanding their near-surface histories on both Mars and Earth. In some martian meteorites, suspected martian preterrestrial alteration products can be distinguished from terrestrial weathering effects Using scanning electron microscopy (SEM), field emission SEM (FE-SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray analysis (EDS), we are studying natural fracture surfaces of ALH 84001 chips, including samples from both the interior and the exterior of the meteorite. Exterior samples include fusion crust surfaces, which are important in determining the extent of terrestrial weathering of meteorites. The focus of this study is weathering features and secondary minerals other than the distinctive carbonate globules that continue to be studied by many researchers.

  11. Evidence for a Second Generation of Magnesite in Martian Meteorite Allan Hills 84001

    NASA Technical Reports Server (NTRS)

    Corrigan, C. M.; Harvey, R. P.

    2003-01-01

    Single-stage formation mechanisms for carbonate and other secondary minerals in ALH84001 are rapidly being revised to include multiple stages of carbonate growth and later thermal and mechanical events including alteration. In an effort to confirm some of these more complex histories we have been studying carbonate-bearing regions within this meteorite. Magnesitic carbonates found in contact with unique 'slab' carbonates in two thin sections of ALH84001 show indications of being of a later generation. The results of our observations help clarify the origins of the carbonate and related minerals in ALH84001, and how these minerals can be used to understand the history of interactions between the martian crust and its volatile inventory.

  12. Polycyclic aromatic hydrocarbons (PAHs) in Antarctic Martian meteorites, carbonaceous chondrites, and polar ice

    SciTech Connect

    Becker, L. |; Glavin, D.P.; Bada, J.L.

    1997-01-01

    Recent analyses of the carbonate globules present in the Martian meteorite ALH84001 have detected polycyclic aromatic hydrocarbons (PAHs) at the ppm level. The distribution of PAHs observed in ALH84001 was interpreted as being inconsistent with a terrestrial origin and were claimed to be indigenous to the meteorite, perhaps derived from an ancient martian biota. We have examined PAHs in the Antarctic shergottite EETA79001, which is also considered to be from Mars, as well as several Antarctic carbonaceous chondrites. We have found that many of the same PAHs detected in the ALH84001 carbonate globules are present in Antarctic carbonaceous chondrites and in both the matrix and carbonate (druse) component of EETA79001. We also investigated PAHs in polar ice and found that carbonate is an effective scavenger of PAHs in ice meltwater. Moreover, the distribution of PAHs in the carbonate extract of Antarctic Allan Hills ice is remarkably similar to that found in both EETA79001 and ALH84001. The reported presence of L-amino acids of apparent terrestrial origin in the EETA79001 druse material suggests that this meteorite is contaminated with terrestrial organics probably derived from Antarctic ice meltwater that had percolated through the meteorite. Our data suggests that the PAHs observed in both ALH84001 and EETA79001 are derived from either the exogenous delivery of organics to Mars or extraterrestrial and terrestrial PAHs present in the ice meltwater or, more likely, from a mixture of these sources. It would appear that PAHs are not useful biomarkers in the search for extinct or extant life on Mars. 33 refs., 3 figs., 1 tab.

  13. Obituary: Allan R. Sandage (1926-2010)

    NASA Astrophysics Data System (ADS)

    Devorkin, David

    2011-12-01

    Allan Rex Sandage died of pancreatic cancer at his home in San Gabriel, California, in the shadow of Mount Wilson, on November 13, 2010. Born in Iowa City, Iowa, on June 18, 1926, he was 84 years old at his death, leaving his wife, former astronomer Mary Connelly Sandage, and two sons, David and John. He also left a legacy to the world of astronomical knowledge that has long been universally admired and appreciated, making his name synonymous with late 20th-Century observational cosmology. The only child of Charles Harold Sandage, a professor of advertising who helped establish that academic specialty after obtaining a PhD in business administration, and Dorothy Briggs Sandage, whose father was president of Graceland College in Iowa, Allan Sandage grew up in a thoroughly intellectual, university oriented atmosphere but also a peripatetic one taking him to Philadelphia and later to Illinois as his father rose in his career. During his 2 years in Philadelphia, at about age eleven, Allan developed a curiosity about astronomy stimulated by a friend's interest. His father bought him a telescope and he used it to systematically record sunspots, and later attempted to make a larger 6-inch reflector, a project left uncompleted. As a teenager Allan read widely, especially astronomy books of all kinds, recalling in particular The Glass Giant of Palomar as well as popular works by Eddington and Hubble (The Realm of the Nebulae) in the early 1940s. Although his family was Mormon, of the Reorganized Church, he was not practicing, though he later sporadically attended a Methodist church in Oxford, Iowa during his college years. Sandage knew by his high school years that he would engage in some form of intellectual life related to astronomy. He particularly recalls an influential science teacher at Miami University in Oxford, Ohio named Ray Edwards, who inspired him to think critically and "not settle for any hand-waving of any kind." [Interview of Allan Rex Sandage by Spencer

  14. Glacial History of the Pirrit Hills, West Antarctica

    NASA Astrophysics Data System (ADS)

    Spector, P. E.; Stone, J. O.

    2014-12-01

    We present new ice-thickness constraints from the Pirrit Hills, a small, far-flung group of nunataks located in the Weddell Sector. At the Pirrit Hills, fresh glacial erratics indicate ice levels ~350-450 m above present during the last ice age. The highest erratics have preliminary 10Be exposure ages of ~16 ka, and the ages generally decrease with decreasing elevation, recording the thinning of the ice in the region. Despite the evidence of thicker ice, weathered bedrock extends down to the present ice level, implying prolonged subaerial weathering prior to the last ice age. These features, and the lack of evidence for wet-based glacial erosion, indicate cold-based and non-erosive ice cover. Over the elevation range in which we found glacial erratics, bedrock 10Be, 26Al, and 21Ne concentrations are consistent with modest ice cover, and have exposure ages ranging from ~0.3-1.5 Myr. Around 450 m above the present ice level, bedrock 10Be, 26Al, and 21Ne concentrations increase by a factor of ~4-5 and do not indicate past ice cover. This height coincides with a break in the otherwise steep slopes of the Pirrit Hills, and the bedrock above is more weathered than the bedrock below. This transition marks the height above which ice cover, if it has occurred in the past few million years, has been very rare, brief, and cold-based. This feature may relate to the trimline imprinted on ridges in the Ellsworth Mountains. In both cases, alpine landscapes have been preserved by a polar climate and glacial highstands rising only partway up the mountain flanks.

  15. Allan Variance Calculation for Nonuniformly Spaced Input Data

    DTIC Science & Technology

    2015-01-01

    Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT The Allan Variance ( AV ) characterizes the...temporal randomness in sensor output data streams at various times scales. The conventional formula for calculating the AV assumes that the data...presents a modified approach to AV calculation, which accommodates nonuniformly spaced time samples. The basic concept of the modified approach is

  16. Allan Sandage : L'architecte de l'expansion

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    1998-07-01

    Il fut de cette poignee de pionniers qui ouvrirent le monde extragalactique. Depuis pres de 50 ans, Allan Sandage poursuit la quete amorcee par le "maitre" Edwin Hubble : mesurer le taux d'expansion de l'Univers. Rencontre avec une legende vivante de la cosmologie...

  17. Numbers Of Degrees Of Freedom Of Allan-Variance Estimators

    NASA Technical Reports Server (NTRS)

    Greenhall, Charles A.

    1992-01-01

    Report discusses formulas for estimation of Allan variances. Presents algorithms for closed-form approximations of numbers of degrees of freedom characterizing results obtained when various estimators applied to five power-law components of classical mathematical model of clock noise.

  18. Biotechnology Symposium - In Memoriam, the Late Dr. Allan Zipf

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A one-day biotechnology symposium was held at Alabama A&M University (AAMU), Normal, AL on June 4, 2004 in memory of the late Dr. Allan Zipf (Sept 1953-Jan 2004). Dr. Zipf was a Research Associate Professor at the Department of Plant and Soil Sciences, AAMU, who collaborated extensively with ARS/MS...

  19. Red Hill Updates

    EPA Pesticide Factsheets

    This and other periodic updates are intended to keep the public informed on major progress being made to protect public health and the environment at the Red Hill Underground Fuel Storage Facility in Hawaii.

  20. David Keynes Hill.

    PubMed

    Huxley, Andrew

    2003-01-01

    David Hill followed his father, A.V. Hill FRS, into the study of muscular contraction. Using a wide range of experimental techniques, he made several important advances of which the most important was the discovery of the 'short-range elastic component', a phenomenon which implied that even in the resting state there was an interaction between the thick (myosin) and thin (actin) filaments. He also studied physical changes in nerve when stimulated.

  1. The Third-Difference Approach to Modified Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, C. A.

    1995-01-01

    This study gives strategies for estimating the modified Allan variance (mvar) and formulas for computing the equivalent degrees of freedom (edf) of the estimators. A third-difference formulation of mvar leads to a tractable formula for edf in the presence of power-law phase noise. The effect of estimation stride on edf is tabulated. First-degree rational-function approximations for edf are derived.

  2. Bacon Hill Substation. Bacon Hill, Cecil Co., MD. Sec. 1201, ...

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

    Bacon Hill Substation. Bacon Hill, Cecil Co., MD. Sec. 1201, MP 48.50. - Northeast Railroad Corridor, Amtrak route between District of Columbia/Maryland state line & Maryland/Delaware state line, Baltimore, Independent City, MD

  3. Allan variance of time series models for measurement data

    NASA Astrophysics Data System (ADS)

    Zhang, Nien Fan

    2008-10-01

    The uncertainty of the mean of autocorrelated measurements from a stationary process has been discussed in the literature. However, when the measurements are from a non-stationary process, how to assess their uncertainty remains unresolved. Allan variance or two-sample variance has been used in time and frequency metrology for more than three decades as a substitute for the classical variance to characterize the stability of clocks or frequency standards when the underlying process is a 1/f noise process. However, its applications are related only to the noise models characterized by the power law of the spectral density. In this paper, from the viewpoint of the time domain, we provide a statistical underpinning of the Allan variance for discrete stationary processes, random walk and long-memory processes such as the fractional difference processes including the noise models usually considered in time and frequency metrology. Results show that the Allan variance is a better measure of the process variation than the classical variance of the random walk and the non-stationary fractional difference processes including the 1/f noise.

  4. Relationship between Allan variances and Kalman Filter parameters

    NASA Technical Reports Server (NTRS)

    Vandierendonck, A. J.; Mcgraw, J. B.; Brown, R. G.

    1984-01-01

    A relationship was constructed between the Allan variance parameters (H sub z, H sub 1, H sub 0, H sub -1 and H sub -2) and a Kalman Filter model that would be used to estimate and predict clock phase, frequency and frequency drift. To start with the meaning of those Allan Variance parameters and how they are arrived at for a given frequency source is reviewed. Although a subset of these parameters is arrived at by measuring phase as a function of time rather than as a spectral density, they all represent phase noise spectral density coefficients, though not necessarily that of a rational spectral density. The phase noise spectral density is then transformed into a time domain covariance model which can then be used to derive the Kalman Filter model parameters. Simulation results of that covariance model are presented and compared to clock uncertainties predicted by Allan variance parameters. A two state Kalman Filter model is then derived and the significance of each state is explained.

  5. Measurement of Allan variance and phase noise at fractions of a millihertz

    NASA Technical Reports Server (NTRS)

    Conroy, Bruce L.; Le, Duc

    1990-01-01

    Although the measurement of Allan variance of oscillators is well documented, there is a need for a simplified system for finding the degradation of phase noise and Allan variance step-by-step through a system. This article describes an instrumentation system for simultaneous measurement of additive phase noise and degradation in Allan variance through a transmitter system. Also included are measurements of a 20-kW X-band transmitter showing the effect of adding a pass tube regulator.

  6. Black Hills hydrology study

    USGS Publications Warehouse

    Driscoll, D.G.

    1994-01-01

    The Black Hills area of western South Dakota is a valuable resource center. The area has attracted numerous residents and industries because of the availability of mineral, timber, agricultural, recreational, and water resources. The water resources of the area have been stressed locally by increasing population, periodic drought, and development of other resources. In response to residents' concerns about these stresses on the water resources, the Black Hills Hydrology Study was initiated in 1990 as a cooperative effort among the U.S. Geological Survey, the South Dakota Department of Environment and Natural Resources, and the West Dakota Water Development District. West Dakota represents the various local and county cooperators. This report describes the purpose, scope, approach, and status of the study and presents highlights from the first project data report produced for the study.

  7. A Simple Algorithm for Approximating Confidence on the Modified Allan Variance and the Time Variance

    NASA Technical Reports Server (NTRS)

    Weiss, Marc A.; Greenhall, Charles A.

    1996-01-01

    An approximating algorithm for computing equvalent degrees of freedom of the Modified Allan Variance and its square root, the Modified Allan Deviation (MVAR and MDEV), and the Time Variance and Time Deviation (TVAR and TDEV) is presented, along with an algorithm for approximating the inverse chi-square distribution.

  8. Pragmatics: The State of the Art: An Online Interview with Keith Allan

    ERIC Educational Resources Information Center

    Allan, Keith; Salmani Nodoushan, Mohammad Ali

    2015-01-01

    This interview was conducted with Professor Keith Allan with the aim of providing a brief but informative summary of the state of the art of pragmatics. In providing answers to the interview questions, Professor Allan begins with a definition of pragmatics as it is practiced today, i.e., the study of the meanings of utterances with attention to…

  9. Nose Hill Artifacts

    ERIC Educational Resources Information Center

    Hansen, Vivian

    2008-01-01

    A Blackfoot woman, caught in the act of adultery, was condemned at this site to have her nose cut off as a penalty for her actions. People do not know her story. The tribe cast it on the ground. And so She, Nose Hill, was named. John Laurie Boulevard holds her mound in a circlet of asphalt, defining the map of her "terra incognita." She…

  10. The dynamic Allan Variance IV: characterization of atomic clock anomalies.

    PubMed

    Galleani, Lorenzo; Tavella, Patrizia

    2015-05-01

    The number of applications where precise clocks play a key role is steadily increasing, satellite navigation being the main example. Precise clock anomalies are hence critical events, and their characterization is a fundamental problem. When an anomaly occurs, the clock stability changes with time, and this variation can be characterized with the dynamic Allan variance (DAVAR). We obtain the DAVAR for a series of common clock anomalies, namely, a sinusoidal term, a phase jump, a frequency jump, and a sudden change in the clock noise variance. These anomalies are particularly common in space clocks. Our analytic results clarify how the clock stability changes during these anomalies.

  11. 'Columbia Hills' from Orbit

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This view of the 'Columbia Hills' in Gusev Crater was made by draping an image from the Mars Orbiter Camera on NASA's Mars Global Surveyor orbiter (image E0300012 from that camera) over a digital elevation model that was derived from two Mars Orbiter Camera images (E0300012 and R0200357).

    This unique view is helpful to the rover team members as they plan the journey of NASA's Mars Exploration Rover Spirit to the base of the Columbia Hills and beyond. Spirit successfully completed a three-month primary mission, and so far remains healthy in an extended mission of bonus exploration. As of sol 135 (on May 21, 2004), Spirit sits approximately 680 meters (0.4 miles) away from its first target at the western base of the hills, a spot informally called 'West Spur.' The team estimates that Spirit will reach West Spur by sol 146 (June 1, 2004). Spirit will most likely remain there for about a week to study the outcrops and rocks associated with this location.

    When done there, Spirit will head approximately 620 meters (0.38 miles) to a higher-elevation location informally called 'Lookout Point.' Spirit might reach Lookout Point by around sol 165 (June 20, 2004). On the way, the rover will pass by and study ripple-shaped wind deposits that may reveal more information about wind processes on Mars.

    Lookout Point will provide a great vantage point for scientists to remotely study the inner basin area of the Columbia Hills. This basin contains a broad range of interesting geological targets including the informally named 'Home Plate' and other possible layered outcrops. These features suggest that the hills contain rock layers. Spirit might investigate the layers to determine whether they are water-deposited sedimentary rock.

    Once at Lookout Point, Spirit will acquire 360-degree panoramic images of the entire area to help define the rover's next steps. Assuming the rover stays healthy, Spirit will eventually drive down into the basin to get an up

  12. Princess Marie Bonaparte, Edgar Allan Poe, and psychobiography.

    PubMed

    Warner, S L

    1991-01-01

    Princess Marie Bonaparte was a colorful yet mysterious member of Freud's inner circle of psychoanalysis. In analysis with Freud beginning in 1925 (she was then 45 years old), she became a lay analyst and writer of many papers and books. Her most ambitious task was a 700-page psychobiography of Edgar Allan Poe that was first published in French in 1933. She was fascinated by Poe's gothic stories--with the return to life of dead persons and the eerie, unexpected turns of events. Her fascination with Poe can be traced to the similarity of their early traumatic life experiences. Bonaparte had lost her mother a month after her birth. Poe's father deserted the family when Edgar was two years old, and his mother died of tuberculosis when he was three. Poe's stories helped him to accommodate to these early traumatic losses. Bonaparte vicariously shared in Poe's loss and the fantasies of the return of the deceased parent in his stories. She was sensitive and empathetic to Poe's inner world because her inner world was similar. The result of this psychological fit between Poe and Bonaparte was her psychobiography, The Life and Works of Edgar Allan Poe. It was a milestone in psychobiography but limited in its psychological scope by its strong emphasis on early childhood trauma. Nevertheless it proved Bonaparte a bona fide creative psychoanalyst and not a dilettante propped up by her friendship with Freud.

  13. Radioactivities in returned lunar materials and in meteorites

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.

    1984-01-01

    Carbon 14 terrestial ages were determined with low level minicomputers and accelerator mass spectrometry on 1 Yamato and 18 Allan Hills and nearby sited meteorites. Techniques for an accelerator mass spectrometer which make C(14) measurements on small samples were developed. Also Be(10) concentrations were measured in Byrd core and Allan Hills ice samples.

  14. KISATCHIE HILLS WILDERNESS, LOUISIANA.

    USGS Publications Warehouse

    Haley, Boyd R.; Ryan, George S.

    1984-01-01

    A mineral-resource survey of the Kisatchie Hills Wilderness, Louisiana indicated little promise for the occurrence of mineral resources. There is insufficient data on oil and gas producing formations that underlie the area to evaluate the oil and gas resource potential. All the oil fields of Wilcox age are less than 40 acres in extent; therefore, closer spaced deeper wells might find additional fields in sediments of Wilcox age. Oil and natural gas have been produced from older reservoirs (Cretaceous age) to the northwest of the wilderness, and deeper wells might find oil and natural gas in sediments of Cretaceous and older age in the vicinity of the wilderness.

  15. Allan Deviation Plot as a Tool for Quartz-Enhanced Photoacoustic Sensors Noise Analysis.

    PubMed

    Giglio, Marilena; Patimisco, Pietro; Sampaolo, Angelo; Scamarcio, Gaetano; Tittel, Frank K; Spagnolo, Vincenzo

    2016-04-01

    We report here on the use of the Allan deviation plot to analyze the long-term stability of a quartz-enhanced photoacoustic (QEPAS) gas sensor. The Allan plot provides information about the optimum averaging time for the QEPAS signal and allows the prediction of its ultimate detection limit. The Allan deviation can also be used to determine the main sources of noise coming from the individual components of the sensor. Quartz tuning fork thermal noise dominates for integration times up to 275 s, whereas at longer averaging times, the main contribution to the sensor noise originates from laser power instabilities.

  16. Seeds of a Soldier: The True Story of Edgar Allan Poe - The Sergeant Major

    DTIC Science & Technology

    2003-01-01

    2003 2. REPORT TYPE 3. DATES COVERED 00-00-2003 to 00-00-2003 4. TITLE AND SUBTITLE Seeds of a Soldier. The true story of Edgar Allan Poe - the...Std Z39-18 Army Space Journal Fall 200360 By Michael L. Howard Seeds of a Soldier The true story of Edgar Allan Poe — the Sergeant Major...the Managing Editor via email to richard.burks@arspace.army.mil dgar Allan Poe wore U.S. Army sergeant major stripes. Using the name Edgar A. Perry

  17. Seizures in the life and works of Edgar Allan Poe.

    PubMed

    Bazil, C W

    1999-06-01

    Edgar Allan Poe, one of the most celebrated of American storytellers, lived through and wrote descriptions of episodic unconsciousness, confusion, and paranoia. These symptoms have been attributed to alcohol or drug abuse but also could represent complex partial seizures, prolonged postictal states, or postictal psychosis. Complex partial seizures were not well described in Poe's time, which could explain a misdiagnosis. Alternatively, he may have suffered from complex partial epilepsy that was complicated or caused by substance abuse. Even today, persons who have epilepsy are mistaken for substance abusers and occasionally are arrested during postictal confusional states. Poe was able to use creative genius and experiences from illness to create memorable tales and poignant poems.

  18. Toilets in the hills.

    PubMed

    Rosenfield, P; Holcombe, S J

    1990-04-01

    Population and Community Development Association (PDA) in Chieng Rai province in northern Thailand implemented its Environmental Sanitation for the Hill Tribes Project in March 1988 to reduce parasite infection and generate interest in self help development projects. As of early 1990, the hill tribes population growth rate stood at 4.5% compared to 1.5% in lowland Thailand. Other problems included villagers defecating around dwellings, not drinking safe water (since none was available), and not wearing shoes all of which contributed to a high rate of parasite infection. In fact, an analysis of stool samples revealed that parasites infected a mean of almost 70% of the villagers. PDA staff informed villagers about basic environmental health information which influenced them to improve sanitation conditions. They also demonstrated how to build the 1st model latrine. After that, each villager designed and constructed his own latrine. Each villager took out a Baht 150 (US$6) loan to pay for the construction materials (squat casings and cement) provided by PDA. Over the following 10 months, the staff returned to the villages to collect payments and to provide technical assistance. Those villagers that constructed a latrine persuaded others to also construct a latrine. In fact, villagers, not always PDA staff, have even transferred the knowledge to other villages. As of early 1990, villagers and staff have built 1000 squats and 993 latrines. With the health education and latrine use, PDA hoped to see a subsequent reduction in parasite infections. With the help of volunteer contraceptive distributors, PDA has also been able to expand its family planning program to 250 villages. It has also initiated a parasite control pilot project in the area in which infection rates have steadily decreased.

  19. Allan-Herndon-Dudley syndrome with unusual profound sensorineural hearing loss.

    PubMed

    Gagliardi, Lucia; Nataren, Nathalie; Feng, Jinghua; Schreiber, Andreas W; Hahn, Christopher N; Conwell, Louise S; Coman, David; Scott, Hamish S

    2015-08-01

    The Allan-Herndon-Dudley syndrome is caused by mutations in the thyroid hormone transporter, Monocarboxylate transporter 8 (MCT8). It is characterized by profound intellectual disability and abnormal thyroid function. We report on a patient with Allan-Herndon-Dudley syndrome (AHDS) with profound sensorineural hearing loss which is not usually a feature of AHDS and which may have been due to a coexisting nonsense mutation in Microphthalmia-associated transcription factor (MITF).

  20. On the application of Allan variance method for Ring Laser Gyro performance characterization

    SciTech Connect

    Ng, L.C.

    1993-10-15

    This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and recursive implementation approaches, validates the Allan variance computation with a simulation model, and illustrates the Allan variance method using data collected from several Honeywell LIMU units.

  1. 3. View of Cherry Hill lettuce shed looking southeast; parking ...

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

    3. View of Cherry Hill lettuce shed looking southeast; parking lot in foreground - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  2. 16. Interior view of Cherry Hill lettuce shed looking up ...

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

    16. Interior view of Cherry Hill lettuce shed looking up at the trusses of the second floor - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  3. 22. View of second floor of the Cherry Hill lettuce ...

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

    22. View of second floor of the Cherry Hill lettuce shed looking at double doors - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  4. 18. View of the second floor of the Cherry Hill ...

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

    18. View of the second floor of the Cherry Hill lettuce shed looking at door - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  5. 20. View of second floor to the Cherry Hill lettuce ...

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

    20. View of second floor to the Cherry Hill lettuce shed looking at floor area - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  6. 12. Partial view of Cherry Hill lettuce shed looking northwest ...

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

    12. Partial view of Cherry Hill lettuce shed looking northwest showing office - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  7. 2. Oblique view of Cherry Hill lettuce shed looking south; ...

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

    2. Oblique view of Cherry Hill lettuce shed looking south; chute building is in background - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  8. 15. Interior view of Cherry Hill lettuce shed showing posts ...

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

    15. Interior view of Cherry Hill lettuce shed showing posts looking towards the chute building - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  9. 21. View of second floor of the Cherry Hill lettuce ...

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

    21. View of second floor of the Cherry Hill lettuce shed looking towards window - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  10. 14. Interior view of Cherry Hill lettuce shed looking towards ...

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

    14. Interior view of Cherry Hill lettuce shed looking towards chute building - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  11. 6. Oblique view of Cherry Hill lettuce shed looking northeast, ...

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

    6. Oblique view of Cherry Hill lettuce shed looking northeast, with chute building to the right - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  12. 19. View of second floor of the Cherry Hill lettuce ...

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

    19. View of second floor of the Cherry Hill lettuce shed looking at door to stairwell - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  13. 9. View of Cherry Hill lettuce shed looking north, with ...

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

    9. View of Cherry Hill lettuce shed looking north, with chute building on the left - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  14. 40Ar-39Ar Studies of the Shocked L6 Chondrites Allan Hills 78003, Yamato 74445, and Yamato 791384

    NASA Astrophysics Data System (ADS)

    Swindle, T. D.; Isachsen, C. E.; Weirich, J. R.; Kimura, M.

    2011-03-01

    Three heavily shocked L6 chondrites clearly record resetting of their K-Ar systems in the last ~1000 Ma. However, their Ar systematics are complicated enough that it is not obvious whether they were involved in the 475 Ma L-chondrite event.

  15. How do the Properties of Allan Hills 84001 Compare With Accepted Criteria for Evidence of Ancient Life?

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.; McKay, D. S.; Thomas-Keprta, K.; Westall, F.; Romanek, C. A.

    1998-01-01

    Criteria for Past Life: To be confident that any sample contains evidence of past life or biogenic activity, one must determine beyond a shadow of a doubt that certain well-established features or biomarker signatures are present in the sample. In the case of martian samples, the criteria for past life have not been established because if life existed on the planet, we have no way of knowing its detailed characteristics. Lacking independent evidence about the nature of possible past life on Mars, the scientific community must use, for the time being, the criteria established for ancient samples from the Earth: (1) Do we know the geologic context of the sample? Is it compatible with past life? (2) Do we know the age of the sample and its stratigraphic location? Are they understood enough to relate possible life to geologic history? (3) Does the sample contain evidence of cellular morphology? (4) What structural remains of colonies or communities exist within the samples? (5) Is there any evidence of biominerals showing chemical or mineral disequilibria? (6) Is there any evidence of stable isotope patterns unique to biology? (7) Are there any organic biomarkers present? (8) Are the features indigenous to the sample? For acceptance of past life in a geologic sample, essentially all of these criteria must he met.

  16. Size-distributions of chondrule types in the Inman and Allan Hills A77011 L3 chondrites

    NASA Technical Reports Server (NTRS)

    Rubin, A. E.; Keil, K.

    1984-01-01

    The size distributions of barred-olivine (BO) and radial-pyroxene/cryptocrystalline (RPC) chondrules are investigated in a petrographic study of nine and 18 thin sections (respectively) of the L3 chondrites Inman and ALHA77011. It is found that the Inman chondrules are significantly larger than the ALHA77011 chondrules and that RPC chondrules in Inman and BO chondrules in ALHA77011 are relatively more numerous, but no significant difference in the BO and RPC size distributions is observed. A formation mechanism involving size sorting of dustball chondrule precursors by aerodynamic particle-gas interactions in a large region of the solar nebula, melting of sorted dustballs in relatively small regions, and chondrule mixing and agglomeration (from subreservoirs containing uniformly large or uniformly small chondrules of a particular compositional type) to form chondrites is proposed.

  17. Mineralization of Bacteria in Terrestrial Basaltic Rocks: Comparison With Possible Biogenic Features in Martian Meteorite Allan Hills 84001

    NASA Technical Reports Server (NTRS)

    Thomas-Keprta, K. L.; McKay, D. S.; Wentworth, S. J.; Stevens, T. O.; Taunton, A. E.; Allen, C. C.; Gibson, E. K., Jr.; Romanek, C. S.

    1998-01-01

    The identification of biogenic features altered by diagenesis or mineralization is important in determining whether specific features in terrestrial rocks and in meteorites may have a biogenic origin. Unfortunately, few studies have addressed the formation of biogenic features in igneous rocks, which may be important to these phenomena, including the controversy over possible biogenic features in basaltic martian meteorite ALH84001. To explore the presence of biogenic features in igneous rocks, we examined microcosms growing in basaltic small-scale experimental growth chambers or microcosms. Microbial communities were harvested from aquifers of the Columbia River Basalt (CRB) group and grown in a microcosm containing unweathered basalt chips and groundwater (technique described in. These microcosms simulated natural growth conditions in the deep subsurface of the CRB, which should be a good terrestrial analog for any putative martian subsurface ecosystem that may have once included ALH84001. Here we present new size measurements and photomicrographs comparing the putative martian fossils to biogenic material in the CRB microcosms. The range of size and shapes of the biogenic features on the CRB microcosm chips overlaps with and is similar to those on ALH84001 chips. Although this present work does not provide evidence for the biogenicity of ALH84001 features, we believe that, based on criteria of size, shape, and general morphology, a biogenic interpretation for the ALH84001 features remains plausible.

  18. Antigravity hills are visual illusions.

    PubMed

    Bressan, Paola; Garlaschelli, Luigi; Barracano, Monica

    2003-09-01

    Antigravity hills, also known as spook hills or magnetic hills, are natural places where cars put into neutral are seen to move uphill on a slightly sloping road, apparently defying the law of gravity. We show that these effects, popularly attributed to gravitational anomalies, are in fact visual illusions. We re-created all the known types of antigravity spots in our laboratory using tabletop models; the number of visible stretches of road, their slant, and the height of the visible horizon were systematically varied in four experiments. We conclude that antigravity-hill effects follow from a misperception of the eye level relative to gravity, caused by the presence of either contextual inclines or a false horizon line.

  19. Radial forcing and Edgar Allan Poe's lengthening pendulum

    NASA Astrophysics Data System (ADS)

    McMillan, Matthew; Blasing, David; Whitney, Heather M.

    2013-09-01

    Inspired by Edgar Allan Poe's The Pit and the Pendulum, we investigate a radially driven, lengthening pendulum. We first show that increasing the length of an undriven pendulum at a uniform rate does not amplify the oscillations in a manner consistent with the behavior of the scythe in Poe's story. We discuss parametric amplification and the transfer of energy (through the parameter of the pendulum's length) to the oscillating part of the system. In this manner, radial driving can easily and intuitively be understood, and the fundamental concept applied in many other areas. We propose and show by a numerical model that appropriately timed radial forcing can increase the oscillation amplitude in a manner consistent with Poe's story. Our analysis contributes a computational exploration of the complex harmonic motion that can result from radially driving a pendulum and sheds light on a mechanism by which oscillations can be amplified parametrically. These insights should prove especially valuable in the undergraduate physics classroom, where investigations into pendulums and oscillations are commonplace.

  20. Allan V. Cox: AGU President 1978”1980

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    When Allan V. Cox was presented AGU's John Adam Fleming Medal in 1969, John Verhoogen described Cox's work as “characterized by painstaking care, proper attention to and use of statistics, and great insight.” Those same thoughts were echoed on February 3, 1987, during the memorial service for Cox, who died in a bicycling accident on January 27. The Stanford Memorial Church was crowded with colleagues, students, and friends.The Fleming Medal was presented to Cox in recognition of his studies on the fluctuation of the geomagnetic field. These studies helped to confirm theories of continental drift and seafloor spreading. The medal is awarded annually by AGU for original research and technical leadership in geomagnetism, atmospheric electricity, aeronomy, and related sciences. In addition to the Fleming Medal, Cox received the Antarctic Service Medal in 1970, the Vetlesen Prize in 1971, and the Arthur L. Day Prize of the National Academy of Sciences in 1984. He was a Fellow of AGU and a member of the National Academy of Sciences.

  1. Online estimation of Allan variance coefficients based on a neural-extended Kalman filter.

    PubMed

    Miao, Zhiyong; Shen, Feng; Xu, Dingjie; He, Kunpeng; Tian, Chunmiao

    2015-01-23

    As a noise analysis method for inertial sensors, the traditional Allan variance method requires the storage of a large amount of data and manual analysis for an Allan variance graph. Although the existing online estimation methods avoid the storage of data and the painful procedure of drawing slope lines for estimation, they require complex transformations and even cause errors during the modeling of dynamic Allan variance. To solve these problems, first, a new state-space model that directly models the stochastic errors to obtain a nonlinear state-space model was established for inertial sensors. Then, a neural-extended Kalman filter algorithm was used to estimate the Allan variance coefficients. The real noises of an ADIS16405 IMU and fiber optic gyro-sensors were analyzed by the proposed method and traditional methods. The experimental results show that the proposed method is more suitable to estimate the Allan variance coefficients than the traditional methods. Moreover, the proposed method effectively avoids the storage of data and can be easily implemented using an online processor.

  2. Ice, Ice, Baby!

    NASA Astrophysics Data System (ADS)

    Hamilton, C.

    2008-12-01

    The Center for Remote Sensing of Ice Sheets (CReSIS) has developed an outreach program based on hands-on activities called "Ice, Ice, Baby". These lessons are designed to teach the science principles of displacement, forces of motion, density, and states of matter. These properties are easily taught through the interesting topics of glaciers, icebergs, and sea level rise in K-8 classrooms. The activities are fun, engaging, and simple enough to be used at science fairs and family science nights. Students who have participated in "Ice, Ice, Baby" have successfully taught these to adults and students at informal events. The lessons are based on education standards which are available on our website www.cresis.ku.edu. This presentation will provide information on the activities, survey results from teachers who have used the material, and other suggested material that can be used before and after the activities.

  3. Application of Allan Deviation to Assessing Uncertainties of Continuous-measurement Instruments, and Optimizing Calibration Schemes

    NASA Astrophysics Data System (ADS)

    Jacobson, Gloria; Rella, Chris; Farinas, Alejandro

    2014-05-01

    Technological advancement of instrumentation in atmospheric and other geoscience disciplines over the past decade has lead to a shift from discrete sample analysis to continuous, in-situ monitoring. Standard error analysis used for discrete measurements is not sufficient to assess and compare the error contribution of noise and drift from continuous-measurement instruments, and a different statistical analysis approach should be applied. The Allan standard deviation analysis technique developed for atomic clock stability assessment by David W. Allan [1] can be effectively and gainfully applied to continuous measurement instruments. As an example, P. Werle et al has applied these techniques to look at signal averaging for atmospheric monitoring by Tunable Diode-Laser Absorption Spectroscopy (TDLAS) [2]. This presentation will build on, and translate prior foundational publications to provide contextual definitions and guidelines for the practical application of this analysis technique to continuous scientific measurements. The specific example of a Picarro G2401 Cavity Ringdown Spectroscopy (CRDS) analyzer used for continuous, atmospheric monitoring of CO2, CH4 and CO will be used to define the basics features the Allan deviation, assess factors affecting the analysis, and explore the time-series to Allan deviation plot translation for different types of instrument noise (white noise, linear drift, and interpolated data). In addition, the useful application of using an Allan deviation to optimize and predict the performance of different calibration schemes will be presented. Even though this presentation will use the specific example of the Picarro G2401 CRDS Analyzer for atmospheric monitoring, the objective is to present the information such that it can be successfully applied to other instrument sets and disciplines. [1] D.W. Allan, "Statistics of Atomic Frequency Standards," Proc, IEEE, vol. 54, pp 221-230, Feb 1966 [2] P. Werle, R. Miicke, F. Slemr, "The Limits

  4. Clarks Hill Lake Water Quality Study.

    DTIC Science & Technology

    1982-06-01

    MACROINVERTEBRATE TAXONOMIC LIST CLARKS HILL LAKE 1981 Phylum Platyhelminthes Order Diptera Class Turbellaria Ablabesmyia parajanta unidentified Planariidae A...HILL LAKE 1981 Phylum Platyhelminthes Order Diptera (continued) Planaria sp.,’ Bezzia sp. 2 unidentified Planariidae Chaoborus punctipennis unidentified

  5. Hill & Knowlton's Two Ethical Dilemmas.

    ERIC Educational Resources Information Center

    Pratt, Cornelius B.

    1994-01-01

    Presents arguments for and against the acceptance, in 1990, of two controversial client accounts by the public relations agency Hill & Knowlton. Examines the ethical implications of both accounts and concludes that whatever ethical infractions may have occurred reflect the agency's dominant public relations practices, not necessarily the "greedy…

  6. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Chalk Hill. 9.52 Section 9... TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  7. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Chalk Hill. 9.52 Section 9... TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  8. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Chalk Hill. 9.52 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  9. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Chalk Hill. 9.52 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  10. On the origin of Hill's causal criteria.

    PubMed

    Morabia, A

    1991-09-01

    The rules to assess causation formulated by the eighteenth century Scottish philosopher David Hume are compared to Sir Austin Bradford Hill's causal criteria. The strength of the analogy between Hume's rules and Hill's causal criteria suggests that, irrespective of whether Hume's work was known to Hill or Hill's predecessors, Hume's thinking expresses a point of view still widely shared by contemporary epidemiologists. The lack of systematic experimental proof to causal inferences in epidemiology may explain the analogy of Hume's and Hill's, as opposed to Popper's, logic.

  11. Allan deviation computations of a linear frequency synthesizer system using frequency domain techniques

    NASA Technical Reports Server (NTRS)

    Wu, Andy

    1995-01-01

    Allan Deviation computations of linear frequency synthesizer systems have been reported previously using real-time simulations. Even though it takes less time compared with the actual measurement, it is still very time consuming to compute the Allan Deviation for long sample times with the desired confidence level. Also noises, such as flicker phase noise and flicker frequency noise, can not be simulated precisely. The use of frequency domain techniques can overcome these drawbacks. In this paper the system error model of a fictitious linear frequency synthesizer is developed and its performance using a Cesium (Cs) atomic frequency standard (AFS) as a reference is evaluated using frequency domain techniques. For a linear timing system, the power spectral density at the system output can be computed with known system transfer functions and known power spectral densities from the input noise sources. The resulting power spectral density can then be used to compute the Allan Variance at the system output. Sensitivities of the Allan Variance at the system output to each of its independent input noises are obtained, and they are valuable for design trade-off and trouble-shooting.

  12. Where Were the Whistleblowers? The Case of Allan McDonald and Roger Boisjoly.

    ERIC Educational Resources Information Center

    Stewart, Lea P.

    Employees who "blow the whistle" on their company because they believe it is engaged in practices that are illegal, immoral, or harmful to the public, often face grave consequences for their actions, including demotion, harassment, forced resignation, or termination. The case of Allan McDonald and Roger Boisjoly, engineers who blew the…

  13. European Studies as Answer to Allan Bloom's "The Closing of the American Mind."

    ERIC Educational Resources Information Center

    Macdonald, Michael H.

    European studies can provide a solution to several of the issues raised in Allan Bloom's "The Closing of the American Mind." European studies pursue the academic quest for what is truth, what is goodness, and what is beauty. In seeking to answer these questions, the Greeks were among the first to explore many of humanity's problems and…

  14. The Allan variance in the presence of a compound Poisson process modelling clock frequency jumps

    NASA Astrophysics Data System (ADS)

    Formichella, Valerio

    2016-12-01

    Atomic clocks can be affected by frequency jumps occurring at random times and with a random amplitude. The frequency jumps degrade the clock stability and this is captured by the Allan variance. In this work we assume that the random jumps can be modelled by a compound Poisson process, independent of the other stochastic and deterministic processes affecting the clock stability. Then, we derive the analytical expression of the Allan variance of a jumping clock. We find that the analytical Allan variance does not depend on the actual shape of the jumps amplitude distribution, but only on its first and second moments, and its final form is the same as for a clock with a random walk of frequency and a frequency drift. We conclude that the Allan variance cannot distinguish between a compound Poisson process and a Wiener process, hence it may not be sufficient to correctly identify the fundamental noise processes affecting a clock. The result is general and applicable to any oscillator, whose frequency is affected by a jump process with the described statistics.

  15. Horror from the Soul--Gothic Style in Allan Poe's Horror Fictions

    ERIC Educational Resources Information Center

    Sun, Chunyan

    2015-01-01

    Edgar Allan Poe made tremendous contribution to horror fiction. Poe's inheritance of gothic fiction and American literature tradition combined with his living experience forms the background of his horror fictions. He inherited the tradition of the gothic fictions and made innovations on it, so as to penetrate to subconsciousness. Poe's horror…

  16. Observation, Inference, and Imagination: Elements of Edgar Allan Poe's Philosophy of Science

    ERIC Educational Resources Information Center

    Gelfert, Axel

    2014-01-01

    Edgar Allan Poe's standing as a literary figure, who drew on (and sometimes dabbled in) the scientific debates of his time, makes him an intriguing character for any exploration of the historical interrelationship between science, literature and philosophy. His sprawling "prose-poem" "Eureka" (1848), in particular, has…

  17. The Art of George Morrison and Allan Houser: The Development and Impact of Native Modernism

    ERIC Educational Resources Information Center

    Montiel, Anya

    2005-01-01

    The idea for a retrospective on George Morrison and Allan Houser as one of the inaugural exhibitions at the National Museum of the American Indian (NMAI) came from the NMAI curator of contemporary art, Truman Lowe. An artist and sculptor himself, Lowe knew both artists personally and saw them as mentors and visionaries. Lowe advised an exhibition…

  18. An Interview with Allan Wigfield: A Giant on Research on Expectancy Value, Motivation, and Reading Achievement

    ERIC Educational Resources Information Center

    Bembenutty, Hefer

    2012-01-01

    This article presents an interview with Allan Wigfield, professor and chair of the Department of Human Development and distinguished scholar-teacher at the University of Maryland. He has authored more than 100 peer-reviewed journal articles and book chapters on children's motivation and other topics. He is a fellow of Division 15 (Educational…

  19. Allan M. Freedman, LLB: a lawyer’s gift to Canadian chiropractors

    PubMed Central

    Brown, Douglas M.

    2007-01-01

    This paper reviews the leadership role, contributions, accolades, and impact of Professor Allan Freedman through a 30 year history of service to CMCC and the chiropractic profession in Canada. Professor Freedman has served as an educator, philanthropist and also as legal counsel. His influence on chiropractic organizations and chiropractors during this significant period in the profession is discussed. PMID:18060008

  20. GEOCHEMISTRY OF MAJUBA HILL, NEVADA.

    USGS Publications Warehouse

    Wenrich, Karen J.; Mascarenas, Joseph F.; Silberman, Miles L.

    1984-01-01

    Majuba Hill is the erosional remnant of a mineralized volcanic complex of rhyolite porphyry stocks, dikes, sills and irregular masses of breccia intruded into Triassic(? ) argillites. Majuba Hill is best known for its Cu and Sn ore; in addition, it was mineralized with other metals of possible economic significance, most notably, Mo, Ag, and U. Although this is an intrusive complex with no evidence of any extrusive phases, it was intruded sufficiently near the surface to develop a porphyritic texture. Intense sericitic and argillic alteration affected all stages of intrusion. Fresh rocks were not available for K-Ar analyses. Several samples of feldspars and sericite from altered zones yielded K-Ar ages for the alteration of 24. 7 to 25. 5 m. y. The tight clustering of ages suggests that all stages of the complex were altered within less than 1 m. y.

  1. Rolling Mill Hill, Nashville, TN

    EPA Pesticide Factsheets

    Rolling Mill Hill was the home to Nashville General Hospital from 1890 to the 1990s and encompassed several buildings and structures. These existing buildings of historical significance were re-used in the form of apartments. The original Trolley Barns on the site are now artists’ lofts and are home to several companies and non-profit offices. Nance Place, which entails additional buildings built on-site, is a Tax Credit Workforce Housing Development and is Platinum LEED certified.

  2. Rocks of the Columbia Hills

    USGS Publications Warehouse

    Squyres, S. W.; Arvidson, R. E.; Blaney, D.L.; Clark, B. C.; Crumpler, L.; Farrand, W. H.; Gorevan, S.; Herkenhoff, K. E.; Hurowitz, J.; Kusack, A.; McSween, H.Y.; Ming, D. W.; Morris, R.V.; Ruff, S.W.; Wang, A.; Yen, A.

    2006-01-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present. Copyright 2006 by the American Geophysical Union.

  3. Rocks of the Columbia Hills

    NASA Astrophysics Data System (ADS)

    Squyres, Steven W.; Arvidson, Raymond E.; Blaney, Diana L.; Clark, Benton C.; Crumpler, Larry; Farrand, William H.; Gorevan, Stephen; Herkenhoff, Kenneth E.; Hurowitz, Joel; Kusack, Alastair; McSween, Harry Y.; Ming, Douglas W.; Morris, Richard V.; Ruff, Steven W.; Wang, Alian; Yen, Albert

    2006-02-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present.

  4. The man and the hill

    USGS Publications Warehouse

    Leopold, Luna Bergere

    1962-01-01

    He was sitting on a large slab of rock. As he looked at the cloud of dust hanging hazily on the horizon, the piece of antler and the block of flint he held in his hand hung as if they were suspended from their previous rapid motion. The man gazed intently across the swaying grass which rose in wave-like billows across the distant hills. What was that dust - a herd of buffalo, a band of hunters, or were coyotes chasing the antelope again? After watching for a while he started again to chip the flint with a rapid twisting motion of the bone in his right hand. The little chips of flint fell in the grass before him. It is the same hill but the scene has changed. Seated on the same rock, holding the reins of a saddle horse, a man dressed in buckskin took the fur cap off his head and wiped his brow. He was looking intently across a brown and desolate landscape at a cloud of dust on the far horizon. Was it the hostile tribe of Indians? It could be buffalo. Nervously he kicked at the ground with the deerhide moccasin, pushing the flint chips out of the way. He wiped the dust from his long rifle. What a terrible place - no water, practically no grass, everything bare and brown. Now at sunset, slanting across the hills green with springtime, a cowman sits on a big rock, pushes his sombrero back on his head, and looks across the valley at a large but quiet herd of stock, moving slowly as each steer walks from one lush patch of grass to another, nibbling. Suddenly he stood up. Far on the horizon some dark objects were moving. Is it the sheepmen? Could it be the stage coach from Baggs to the Sweetwater Crossing?Same hill - a gray truck was grinding slowly toward the summit. It pulled up near a small fenced enclosure where there were some instruments painted a bright silver color. A man stepped out of the truck and turned to his younger companion, "You've never found an arrowhead? Maybe you have never thought about it correctly. If you want to find where an Indian camped long

  5. Terrestrial ice streams-a view from the lobe

    USGS Publications Warehouse

    Jennings, C.E.

    2006-01-01

    The glacial landforms of Minnesota are interpreted as the products of the lobate extensions of ice streams that issued from various ice sheds within the Laurentide Ice Sheet. Low-relief till plains, trough-shaped lowlands, boulder pavements, and streamlined forms make up the subglacial landsystem in Minnesota that is interpreted as having been formed by streaming ice. Extremely uniform tills are created subglacially in a way that remains somewhat mysterious. At the ice margins, thrust moraines and hummocky stagnation topography are more common than single-crested, simple moraines if the ice lobes had repeated advances. Subglacial drainage features are obscure up-ice but are present down-ice in the form of tunnel valleys, eskers, Spooner hills, and associated ice-marginal fans. Ice streaming may occur when basal shear stress is lowered as a result of high subglacial water pressure. Subglacial conditions that allow the retention of water will allow an ice lobe to extend far beyond the ice sheet as long as the ice shed also supports the advance by supplying adequate ice. Even with adequate ice flux, however, the advance of an ice lobe may be terminated, at least temporarily, if the subglacial water is drained, through tunnel valleys or perhaps a permeable substrate. Thrust moraines, and ice stagnation topography will result from sudden drainage. Although climate change is ultimately responsible for the accumulation of ice in the Laurentide Ice Sheet, the asynchronous advances and retreats of the ice lobes in the mid-continent are strongly overprinted by the internal dynamics of individual ice streams as well as the interaction of ice sheds, which obscure the climate signal. ?? 2005 Elsevier B.V. All rights reserved.

  6. Keeping pace with Capitol Hill

    USGS Publications Warehouse

    Cooper, C.

    2007-01-01

    At the Capitol Hill, the legislative branch of the United States government, the work is always at pace. Working with Congress is a tough job yet, rewarding. The Congress worked hard together to serve the public interest but many big issues are one small part of what Congress does. However, many US news media do not report what the government does instead, the media report what the government argues about. The media reports the conflicts but story is always incomplete. In order for the people know what is happening to the government, contact the congressional representative to know the complete story.

  7. Allan C. Gotlib, DC, CM: A worthy Member of the Order of Canada.

    PubMed

    Brown, Douglas M

    2016-03-01

    On June 29, 2012, His Excellency the Right Honourable David Johnston, Governor General of Canada, announced 70 new appointments to the Order of Canada. Among them was Dr. Allan Gotlib, who was subsequently installed as a Member of the Order of Canada, in recognition of his contributions to advancing research in the chiropractic profession and its inter-professional integration. This paper attempts an objective view of his career, to substantiate the accomplishments that led to Dr. Gotlib receiving Canada's highest civilian honour.

  8. Spirit Rover on 'Husband Hill'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1: Location of Spirit

    Two Earth years ago, NASA's Mars Exploration Rover Spirit touched down in Gusev Crater. The rover marked its first Mars-year (687 Earth days) anniversary in November 2005. Shortly before Spirit's Martian anniversary, the Mars Orbiter Camera on NASA's Mars Global Surveyor acquired an image covering approximately 3 kilometers by 3 kilometers (1.9 miles by 1.9 miles) centered on the rover's location at that time in the 'Columbia Hills.'

    'Husband Hill,' the tallest in the range, is just below the center of the image. The image has a resolution of about 50 centimeters (1.6 feet) per pixel. North is up; illumination is from the left. The location is near 14.8 degrees south latitude, 184.6 degrees west longitude.

    The image was acquired on Nov. 2, 2005. A white box (see Figure 1) indicates the location of an excerpted portion on which the location of Spirit on that date is marked. Dr. Timothy J. Parker of the Mars Exploration Rover team at the NASA's Jet Propulsion Laboratory, Pasadena, Calif., confirmed the location of the rover in the image. The region toward the bottom of the image shows the area where the rover is currently headed. The large dark patch and other similar dark patches are accumulations of windblown sand and granules.

  9. Sea Ice

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.; Cavalieri, Donald J.

    2005-01-01

    Sea ice covers vast areas of the polar oceans, with ice extent in the Northern Hemisphere ranging from approximately 7 x 10(exp 6) sq km in September to approximately 15 x 10(exp 6) sq km in March and ice extent in the Southern Hemisphere ranging from approximately 3 x 10(exp 6) sq km in February to approximately 18 x 10(exp 6) sq km in September. These ice covers have major impacts on the atmosphere, oceans, and ecosystems of the polar regions, and so as changes occur in them there are potential widespread consequences. Satellite data reveal considerable interannual variability in both polar sea ice covers, and many studies suggest possible connections between the ice and various oscillations within the climate system, such as the Arctic Oscillation, North Atlantic Oscillation, and Antarctic Oscillation, or Southern Annular Mode. Nonetheless, statistically significant long-term trends are also apparent, including overall trends of decreased ice coverage in the Arctic and increased ice coverage in the Antarctic from late 1978 through the end of 2003, with the Antarctic ice increases following marked decreases in the Antarctic ice during the 1970s. For a detailed picture of the seasonally varying ice cover at the start of the 21st century, this chapter includes ice concentration maps for each month of 2001 for both the Arctic and the Antarctic, as well as an overview of what the satellite record has revealed about the two polar ice covers from the 1970s through 2003.

  10. Measurements of Ultra-Stable Oscillator (USO) Allan Deviations in Space

    NASA Technical Reports Server (NTRS)

    Enzer, Daphna G.; Klipstein, William M.; Wang, Rabi T.; Dunn, Charles E.

    2013-01-01

    Researchers have used data from the GRAIL mission to the Moon to make the first in-flight verification of ultra-stable oscillators (USOs) with Allan deviation below 10 13 for 1-to-100-second averaging times. USOs are flown in space to provide stable timing and/or navigation signals for a variety of different science and programmatic missions. The Gravity Recovery and Interior Laboratory (GRAIL) mission is flying twin spacecraft, each with its own USO and with a Ka-band crosslink used to measure range fluctuations. Data from this crosslink can be combined in such a way as to give the relative time offsets of the two spacecrafts USOs and to calculate the Allan deviation to describe the USOs combined performance while orbiting the Moon. Researchers find the first direct in-space Allan deviations below 10(exp -13) for 1-to-100-second averaging times comparable to pre-launch data, and better than measurements from ground tracking of an X-band carrier coherent with the USO. Fluctuations in Earth s atmosphere limit measurement performance in direct-to-Earth links. Inflight USO performance verification was also performed for GRAIL s parent mission, the Gravity Recovery and Climate Experiment (GRACE), using both Kband and Ka-band crosslinks.

  11. On the Design of Attitude-Heading Reference Systems Using the Allan Variance.

    PubMed

    Hidalgo-Carrió, Javier; Arnold, Sascha; Poulakis, Pantelis

    2016-04-01

    The Allan variance is a method to characterize stochastic random processes. The technique was originally developed to characterize the stability of atomic clocks and has also been successfully applied to the characterization of inertial sensors. Inertial navigation systems (INS) can provide accurate results in a short time, which tend to rapidly degrade in longer time intervals. During the last decade, the performance of inertial sensors has significantly improved, particularly in terms of signal stability, mechanical robustness, and power consumption. The mass and volume of inertial sensors have also been significantly reduced, offering system-level design and accommodation advantages. This paper presents a complete methodology for the characterization and modeling of inertial sensors using the Allan variance, with direct application to navigation systems. Although the concept of sensor fusion is relatively straightforward, accurate characterization and sensor-information filtering is not a trivial task, yet they are essential for good performance. A complete and reproducible methodology utilizing the Allan variance, including all the intermediate steps, is described. An end-to-end (E2E) process for sensor-error characterization and modeling up to the final integration in the sensor-fusion scheme is explained in detail. The strength of this approach is demonstrated with representative tests on novel, high-grade inertial sensors. Experimental navigation results are presented from two distinct robotic applications: a planetary exploration rover prototype and an autonomous underwater vehicle (AUV).

  12. Estimating the Allan variance in the presence of long periods of missing data and outliers

    NASA Astrophysics Data System (ADS)

    Sesia, Ilaria; Tavella, Patrizia

    2008-12-01

    The ability of the Allan variance (AVAR) to identify and estimate the typical clock noise is widely accepted, and its use is recommended by international standards. Recently, a time-varying version called Dynamic Allan variance (DAVAR) was suggested and exploited. Currently, the AVAR is commonly used in applications to space and satellite systems, in particular in monitoring the clocks of the Global Positioning System, and also in the framework of the European project Galileo. In these applications stability estimation, either AVAR or DAVAR (or other similar variances), presents some peculiar aspects which are not commonly encountered when the clock data are measured in a laboratory. In particular, data from space clocks may typically present outliers and missing values. Hence, special attention has to be paid when dealing with such experimental measurements. In this work we propose an estimation algorithm and its implementation in a robust software code (in MATLAB® language) able to estimate the AVAR in the case of missing data, unequally spaced data, outliers, and with long periods of missing observation, so that the Allan variance estimates turn out unbiased and with the maximum use of all the available data.

  13. Over Ice

    NASA Video Gallery

    All about NASA's IceBridge P-3B plane and its IceBridge retrofit. Upgraded with 21st century "special modifications", the aircraft is less a cold war relic and more like the Space Agency's Millenni...

  14. 7. Detail of balcony rail. August 1936. Joseph Hill, photographer, ...

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

    7. Detail of balcony rail. August 1936. Joseph Hill, photographer, copied from small photo taken by survey member. - Jansonist Colony, Steeple Building, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  15. 1. Historic American Buildings Survey Joseph Hill, Photographer August 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer August 1936 FIRST ORIGINAL STORE AND POSTOFFICE, COPY OF AN EARLY PHOTOGRAPH. LENT BY EVELYN S. CRAIG - Jansonist Colony, Colony Store & Post Office, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  16. 6. Detail of pilaster cap. Aug. 10, 1936. Joseph Hill, ...

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

    6. Detail of pilaster cap. Aug. 10, 1936. Joseph Hill, photographer, copied from small photo taken by survey member. - Jansonist Colony, Steeple Building, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  17. 3. West and south elevations. Joseph Hill, photographer, copied from ...

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

    3. West and south elevations. Joseph Hill, photographer, copied from photo lent by Evelyn S. Craig. August 1936. - Jansonist Colony, Steeple Building, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  18. Glaciated appalachian plateau: till shadows on hills.

    PubMed

    Coates, D R

    1966-06-17

    North slopes are twice as steep as south slopes on the hills of central New York. This asymmetry is caused by unequal till thickness-3.6 meters on north slopes and 27.6 meters on south slopes. Previous workers interpreted the hills as being of bedrock sculptured by glacial erosion, with till 0.9 to 3 meters thick.

  19. Report on the Black Hills Alliance.

    ERIC Educational Resources Information Center

    Ryan, Joe

    1979-01-01

    A rally to save the Black Hills from coal- and uranium-greedy energy companies was held on July 6 and over 2,000 joined in a 15-mile walk on July 7 in Rapid City, South Dakota. The Black Hills Alliance, an Indian coalition concerned about energy development proposals in the Great Plains, sponsored the gathering. (NQ)

  20. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake Hills”. For purposes of part 4 of this chapter, “Rattlesnake Hills” is a term of viticultural significance....

  1. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake Hills”. For purposes of part 4 of this chapter, “Rattlesnake Hills” is a term of viticultural significance....

  2. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake Hills”. For purposes of part 4 of this chapter, “Rattlesnake Hills” is a term of viticultural significance....

  3. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake Hills”. For purposes of part 4 of this chapter, “Rattlesnake Hills” is a term of viticultural significance....

  4. Colleges as Shining Cities on a Hill

    ERIC Educational Resources Information Center

    Townsend, Kathleen Kennedy

    2012-01-01

    In this article, the author proposes that the notion of America be reintroduced as the "shining city on a hill," that abiding image from American history. The image of the shining city on a hill captures the imagination because it reflects the abiding truth that people become fully human in society, not outside of it. People need one…

  5. Impact craters as biospheric microenvironments, Lawn Hill Structure, Northern Australia.

    PubMed

    Lindsay, John; Brasier, Martin

    2006-04-01

    Impact craters on Mars act as traps for eolian sediment and in the past may have provided suitable microenvironments that could have supported and preserved a stressed biosphere. If this is so, terrestrial impact structures such as the 18-km-diameter Lawn Hill Structure, in northern Australia, may prove useful as martian analogs. We sampled outcrop and drill core from the carbonate fill of the Lawn Hill Structure and recorded its gamma-log signature. Facies data along with whole rock geochemistry and stable isotope signatures show that the crater fill is an outlier of the Georgina Basin and was formed by impact at, or shortly before, approximately 509-506 million years ago. Subsequently, it was rapidly engulfed by the Middle Cambrian marine transgression, which filled it with shallow marine carbonates and evaporites. The crater formed a protected but restricted microenvironment in which sediments four times the thickness of the nearby basinal succession accumulated. Similar structures, common on the martian surface, may well have acted as biospheric refuges as the planet's water resources declined. Low-pH aqueous environments on Earth similar to those on Mars, while extreme, support diverse ecologies. The architecture of the eolian crater fill would have been defined by long-term ground water cycles resulting from intermittent precipitation in an extremely arid climate. Nutrient recycling, critical to a closed lacustrine sub-ice biosphere, could be provided by eolian transport onto the frozen water surface.

  6. Late-glacial and postglacial history of the hill'', Norwich University campus, Northfield, Vermont

    SciTech Connect

    Larsen, F.D. . Dept. of Geology)

    1993-03-01

    The central part of the Norwich University campus at Northfield is built on a kame about 60 ft high on the side of the Dog River valley. Significant excavations made between 1979 and 1991 in the flank of the hill provide details about its glacial origin. Collapsed ice-contact lake deposits on the northwestern flank of the kame are overlain by undisturbed lake sediments formed by turbidity currents that moved southward in glacial Lake Roxbury. Lake Roxbury formed when the retreating ice margin blocked the north-draining Dog River valley and caused melt water to drain south over a 1,010-foot threshold at Roxbury. The lowest deposits exposed on the southeast flank of the kame are highly deformed and include a chaotic slide breccia overlain by progressively less deformed lake-bottom sediments. Northward retreat of the ice margin permitted Lake Roxbury to drop 80 ft to the level of glacial Lake Winooski, which still left 80 ft of lake water over the top of the hill''. Following the lowering of Lake Winooski, stream terraces were cut on the west flank of the hill''. The terraces are underlain by imbricated pebble gravel deposited by the north-flowing Dog River that probably was graded to a lower glacial lake in the Winooski River valley to the north. Downcutting by the Dog River and subsequent lateral migration of its meanders produced the topography the authors see today. The late-glacial and postglacial history can be summarized as follows: (1) deposition of lake sediments in contact with buried ice, (2) collapse and continued deposition of lake sediments during melting of buried ice, (3) deposition of undeformed lake sediments, (4) drainage of glacial lakes, and (5) development of stream terraces and the modern flood plain.

  7. Allan Variance Computed in Space Domain: Definition and Application to InSAR Data to Characterize Noise and Geophysical Signal.

    PubMed

    Cavalié, Olivier; Vernotte, François

    2016-04-01

    The Allan variance was introduced 50 years ago for analyzing the stability of frequency standards. In addition to its metrological interest, it may be also considered as an estimator of the large trends of the power spectral density (PSD) of frequency deviation. For instance, the Allan variance is able to discriminate different types of noise characterized by different power laws in the PSD. The Allan variance was also used in other fields than time and frequency metrology: for more than 20 years, it has been used in accelerometry, geophysics, geodesy, astrophysics, and even finances. However, it seems that up to now, it has been exclusively applied for time series analysis. We propose here to use the Allan variance on spatial data. Interferometric synthetic aperture radar (InSAR) is used in geophysics to image ground displacements in space [over the synthetic aperture radar (SAR) image spatial coverage] and in time thanks to the regular SAR image acquisitions by dedicated satellites. The main limitation of the technique is the atmospheric disturbances that affect the radar signal while traveling from the sensor to the ground and back. In this paper, we propose to use the Allan variance for analyzing spatial data from InSAR measurements. The Allan variance was computed in XY mode as well as in radial mode for detecting different types of behavior for different space-scales, in the same way as the different types of noise versus the integration time in the classical time and frequency application. We found that radial Allan variance is the more appropriate way to have an estimator insensitive to the spatial axis and we applied it on SAR data acquired over eastern Turkey for the period 2003-2011. Spatial Allan variance allowed us to well characterize noise features, classically found in InSAR such as phase decorrelation producing white noise or atmospheric delays, behaving like a random walk signal. We finally applied the spatial Allan variance to an InSAR time

  8. Myelination Delay and Allan-Herndon-Dudley Syndrome Caused by a Novel Mutation in the SLC16A2 Gene.

    PubMed

    La Piana, Roberta; Vanasse, Michel; Brais, Bernard; Bernard, Genevieve

    2015-09-01

    Allan-Herndon-Dudley syndrome is an X-linked disease caused by mutations in the solute carrier family 16 member 2 (SLC16A2) gene. As SLC16A2 encodes the monocarboxylate transporter 8 (MCT8), a thyroid hormone transporter, patients with Allan-Herndon-Dudley syndrome present a specific altered thyroid hormone profile. Allan-Herndon-Dudley syndrome has been associated with myelination delay on the brain magnetic resonance imaging (MRI) of affected subjects. We report a patient with Allan-Herndon-Dudley syndrome characterized by developmental delay, hypotonia, and delayed myelination caused by a novel SLC16A2 mutation (p.L291R). The thyroid hormones profile in our patient was atypical for Allan-Herndon-Dudley syndrome. The follow-up examinations showed that the progression of the myelination was not accompanied by a clinical improvement. Our paper suggests that SLC16A2 mutations should be investigated in patients with myelination delay even when the thyroid function is not conclusively altered.

  9. Descent from the Summit of 'Husband Hill'

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for Descent from the Summit of 'Husband Hill' (QTVR)

    In late November 2005 while descending 'Husband Hill,' NASA's Mars Exploration Rover Spirit took the most detailed panorama so far of the 'Inner Basin,' the rover's next target destination. Spirit acquired the 405 individual images that make up this 360-degree view of the surrounding terrain using five different filters on the panoramic camera. The rover took the images on Martian days, or sols, 672 to 677 (Nov. 23 to 28, 2005 -- the Thanksgiving holiday weekend).

    This image is an approximately true-color rendering using camera's 750-, 530-, and 430-nanometer filters. Seams between individual frames have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see.

    'Home Plate,' a bright, semi-circular feature scientists hope to investigate, is harder to discern in this image than in earlier views taken from higher up the hill. Spirit acquired this more oblique view, known as the 'Seminole panorama,' from about halfway down the south flank of Husband Hill, 50 meters (164 feet) or so below the summit. Near the center of the panorama, on the horizon, are 'McCool Hill' and 'Ramon Hill,' named, like Husband Hill, in honor of the fallen astronauts of the space shuttle Columbia. Husband Hill is visible behind the rover, on the right and left sides of the panorama. An arc of rover tracks made while avoiding obstacles and getting into position to examine rock outcrops can be traced over a long distance by zooming in to explore the panorama in greater detail.

    Spirit is now significantly farther downhill toward the center of this panorama, en route to Home Plate and other enigmatic soils and outcrop rocks in the quest to uncover the history of Gusev Crater and the 'Columbia Hills.'

  10. A SYMPLECTIC INTEGRATOR FOR HILL'S EQUATIONS

    SciTech Connect

    Quinn, Thomas; Barnes, Rory; Perrine, Randall P.; Richardson, Derek C.

    2010-02-15

    Hill's equations are an approximation that is useful in a number of areas of astrophysics including planetary rings and planetesimal disks. We derive a symplectic method for integrating Hill's equations based on a generalized leapfrog. This method is implemented in the parallel N-body code, PKDGRAV, and tested on some simple orbits. The method demonstrates a lack of secular changes in orbital elements, making it a very useful technique for integrating Hill's equations over many dynamical times. Furthermore, the method allows for efficient collision searching using linear extrapolation of particle positions.

  11. Exploring Hill Ciphers with Graphing Calculators.

    ERIC Educational Resources Information Center

    St. John, Dennis

    1998-01-01

    Explains how to code and decode messages using Hill ciphers which combine matrix multiplication and modular arithmetic. Discusses how a graphing calculator can facilitate the matrix and modular arithmetic used in the coding and decoding procedures. (ASK)

  12. Streamlined Hills of Maja Vallis

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 16 May 2003

    Classic catastrophic flood morphology (streamlined hills and longitudinal grooves) is captured in this image of Lunae Planum. Similar features (although much smaller in size) are seen in terrestrial catastrophic flood regions such as Channeled Scabland of Washington state and in Iceland.

    Image information: VIS instrument. Latitude 14.8, Longitude 301.8East (58.2). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  13. The Igwisi Hills extrusive 'kimberlites'

    NASA Technical Reports Server (NTRS)

    Reid, A. M.; Donaldson, C. H.; Dawson, J. B.; Brown, R. W.; Ridley, W. I.

    1975-01-01

    The petrography and mineral chemistry of volcanic rocks from the Igwisi Hills in Tanzania are discussed. There is considerable evidence to suggest that the Igwisi rocks are extrusive kimberlites: a two-component nature with high P-T minerals in a low P-T matrix; the presence of chrome pyrope, Al enstatite, chrome diopside, chromite and olivine; a highly oxidized, volatile-rich matrix with serpentine, calcite, magnetite, perovskite; high Sr, Zr, and Nb contents; occurrence in a narrow isolated vent within a stable shield area. The Igwisi rocks differ from kimberlite in the lack of magnesian ilmenite, the scarcity of matrix phlogopite, and the overall low alkali content. They apparently contain material from phlogopite-bearing garnet peridotites with a primary mineral assemblage indicative of equilibrium at upper mantle temperatures and pressures. This primary assemblage was brought rapidly to the surface in a gas-charged, carbonate-rich fluid. Rapid upward transport, extrusion, and rapid cooling have tended to prevent reaction between inclusions and the carbonate-rich matrix that might otherwise have yielded a more typical kimberlite.

  14. A perspective on Capitol Hill

    NASA Astrophysics Data System (ADS)

    Hodges, Carroll Ann

    As the AGU Congressional Science Fellow for 1980-1981, I had a unique opportunity to witness the federal engine in action—a remarkable piece of machinery. The American Association for the Advancement of Science organized an excellent orientation program, introducing our class of science fellows (about 30) to the kinds of options available for a year's tenure on Capitol Hill. These include affiliation with a congressman's or senator's staff or with one of the hundred or so standing, select, or joint committees and subcommittees. I arranged to join the personal staff of Congressman Jim Santini (D, Nev.), largely because of his demonstrated interest in Department of Interior affairs in general and the minerals industry in particular. The position of fellow provides no guarantee of work in one's areas of expertise or inclination, however, and I found that my staff assignments included topics ranging from wild horses to peanut subsidies. My principal task involved evaluation of the Air Force proposal to deploy the MX missile in Nevada and the consequent impact of that incredible scheme on the physical and economic environments of the state and the nation, including effects on minerals exploration. I had not expected to become conversant with missile technology, but the exercise provided quite an education.

  15. Allan C. Gotlib, DC, CM: A worthy Member of the Order of Canada

    PubMed Central

    Brown, Douglas M.

    2016-01-01

    On June 29, 2012, His Excellency the Right Honourable David Johnston, Governor General of Canada, announced 70 new appointments to the Order of Canada. Among them was Dr. Allan Gotlib, who was subsequently installed as a Member of the Order of Canada, in recognition of his contributions to advancing research in the chiropractic profession and its inter-professional integration. This paper attempts an objective view of his career, to substantiate the accomplishments that led to Dr. Gotlib receiving Canada’s highest civilian honour. PMID:27069273

  16. Investigation of Allan variance for determining noise spectral forms with application to microwave radiometry

    NASA Technical Reports Server (NTRS)

    Stanley, William D.

    1994-01-01

    An investigation of the Allan variance method as a possible means for characterizing fluctuations in radiometric noise diodes has been performed. The goal is to separate fluctuation components into white noise, flicker noise, and random-walk noise. The primary means is by discrete-time processing, and the study focused primarily on the digital processes involved. Noise satisfying the requirements was generated by direct convolution, fast Fourier transformation (FFT) processing in the time domain, and FFT processing in the frequency domain. Some of the numerous results obtained are presented along with the programs used in the study.

  17. Sea Ice

    NASA Technical Reports Server (NTRS)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.

    2013-01-01

    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  18. Unravelling Younger Dryas glaciation in the Tweedsmuir Hills, Southern Uplands, Scotland.

    NASA Astrophysics Data System (ADS)

    Pearce, Danni; Rea, Brice; Barr, Iesytn; Everest, Jeremy; Primmer, Nick; Langdon, Pete; Edwards, Mary; McDougall, Des

    2013-04-01

    In Britain, the glacial geomorphological record has been widely utilised to infer palaeo-glacier geometries and ice dynamics with much of this work focussing on the Scottish Highlands during the Last Glacial Interglacial Transition (LGIT), in particular the Younger Dryas (YD; c. 12.9 - 11.7 ka BP). The Southern Uplands represents the largest upland area south of the Highlands but have received limited research attention over the last century. The Tweedsmuir Hills are located in the central Southern Uplands, which form an area of dissected plateau approximately 320 km2. Early research in the 1800s identified a range of glacial landforms thought to be associated with the YD. The majority of previous work has focussed on isolated valleys and ignored the potential for plateau icefield glaciation, which has significant implications for understanding of the dynamics and geometries of the YD ice masses. Recent numerical modelling experiments covering the period 38 - 10.4 ka BP (Hubbard et al., 2008 cf. E109B8 and E102b2) have predicted a significant body of ice for the Southern Uplands at the onset of and throughout the YD, which cannot be verified at present due to a lack of empirical data. This research aims to provide the first systematic mapping and climate reconstruction for the Tweedsmuir Hills. The results of air-photo interpretation and field mapping, which utilised a morphostratigraphic approach, has demonstrated a more extensive glaciation than previously mapped. This consists of two separate icefields over the southern and northern Tweedsmuir Hills which cover an area c. 45 km2 and 25 km2 respectively with Equilibrium Line Altitudes (ELAs) calculated to have ranged from c. 419 m to 634 m. For both icefields ELAs of individual outlets reflect topographic controls rather than steep precipitation gradients like those derived for other icefields in Scotland (e.g., the Monadhliath Mountains and Beinn Dearg). New radiocarbon dating of basal stratigraphies and

  19. Multifrequency Retrieval of Cloud Ice Particle Size Distributions

    DTIC Science & Technology

    2005-01-01

    calculate the scattering by nonspherical particles. The T - matrix code was obtained from Barber and Hill (1990) for axi-symmetric oblate spheroids...wave, the T - matrix code calculates the scattering characteristics for a nonspherical particle. The T-matrix nonspherical ice particles are oblate

  20. Drought in the Black Hills

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Annotated Color-Coded Map

    Despite good rainfall and record-setting snowstorms in the spring of 2005, most of northeastern Wyoming, the Black Hills, and western South Dakota remain in the midst of a severe drought. This set of images and maps from NASA's Multi-angle Imaging SpectroRadiometer (MISR) contrast the appearance of the Black Hills region of northwestern South Dakota on July 12, 2000 (left column), with views acquired four years later, on July 14, 2004 (right column). The natural-color images along the top are from MISR's nadir (downward-looking) camera. The browning that appears in 2004 compared with 2000 indicates that the vigor of green vegetation was significantly diminished in 2004.

    The color-coded maps (along the bottom) provide a quantitative measurement of the sunlight reflected from these surfaces, and the loss of sunlight-absorbing vegetation between the 2000 and 2004 dates. As the vegetation faded with the drought, the albedo at the surface increased. Albedo measures the fraction of incident sunlight that is reflected by a surface, and can vary between zero (if all the incident sunlight is absorbed and none is reflected) and one (if all sunlight is reflected and none is absorbed). Dense forest has a low albedo; bright desert, snow and clouds, have a high albedo. Here, albedo is provided for the wavelengths of sunlight that plants use for photosynthesis (400 - 700 nanometers). This measurement is known as the albedo for Photosynthetically Active Radiation (PAR). Surfaces with greater absorption of PAR appear here in blue hues, whereas surfaces with lower absorption appear as green, yellow, orange or red. Black pixels indicate areas where albedo could not be derived, usually due to the presence of clouds. In July 2004, low albedo areas (blue pixels) are notably reduced in extent, and higher albedo areas (yellow, orange and red pixels) have increased.

    Because incoming sunlight is

  1. Evidence for Repeated Early Miocene Glaciation and the Cutting of Upper Taylor Valley from the Friis Hills, Antarctica

    NASA Astrophysics Data System (ADS)

    Lewis, A.; Ashworth, A. C.; Marchant, D. R.; Hemming, S. R.

    2009-12-01

    The Friis Hills, located at the head of Taylor Valley in the the McMurdo Dry Valleys, hold a sequence of stacked tills at least Early Miocene in age. Sedimentology, clast lithology and bedrock striations indicate these tills were deposited from wet-based glaciers that flowed southeastward down a shallow paleovalley toward the Ferrar trough. Interbedded paleosols, fluvial, and glaciolacustrine deposits register ice-free periods when the valley held small streams and ponds. Exceptionally well-preserved fossil biota suggests mild conditions during at least two of these interglacial episodes. Proglacial lacustrine deposits that include dropstones and debris flows mark the return of glacial conditions but fossil leaves and wood of Nothofagus suggest conditions during the initial phase of ice advance were also relatively mild. Geomorphic relationships show that major valley incision must have taken place after deposition of these sediments as the Friis Hills is today a flat-topped inselberg, about 5 km across, isolated from nearby topography by the deep glacial troughs of the Taylor Valley drainage. A second suite of tills, directly overlying the first, registers a reorganized glacial system with ice streaming eastward, roughly parallel to Taylor Valley. Like the first, these tills were deposited during repeated ice advances but glaciers never fully inundated the Friis Hills and ice-free periods are marked by only weak weathering surfaces and thin glaciolacustrine deposits. We interpret the changing glacial pattern to reflect headward cutting in upper Taylor Valley and the capture of ice from the Ferrar drainage. A volcanic ash interbed dated by Ar-Ar at 19.76 (±0.11) Ma occurs in a Taylor Valley-oriented drift near the eastern edge of the Friis Hills plateau. Based on its stratigraphic position, the older suite of tills and fossil-bearing interbeds are >19.76 Ma. Underlying bedrock striations show that ice flow had been redirected into Taylor Valley by this time. The

  2. Bunker Hill Sediment Characterization Study

    SciTech Connect

    Neal A. Yancey; Debby F. Bruhn

    2009-12-01

    The long history of mineral extraction in the Coeur d’Alene Basin has left a legacy of heavy metal laden mine tailings that have accumulated along the Coeur d’Alene River and its tributaries (U.S. Environmental Protection Agency, 2001; Barton, 2002). Silver, lead and zinc were the primary metals of economic interest in the area, but the ores contained other elements that have become environmental hazards including zinc, cadmium, lead, arsenic, nickel, and copper. The metals have contaminated the water and sediments of Lake Coeur d’Alene, and continue to be transported downstream to Spokane Washington via the Spokane River. In 1983, the EPA listed the Bunker Hill Mining and Metallurgical Complex on the National Priorities List. Since that time, many of the most contaminated areas have been stabilized or isolated, however metal contaminants continue to migrate through the basin. Designation as a Superfund site causes significant problems for the economically depressed communities in the area. Identification of primary sources of contamination can help set priorities for cleanup and cleanup options, which can include source removal, water treatment or no action depending on knowledge about the mobility of contaminants relative to water flow. The mobility of contaminant mobility under natural or engineered conditions depends on multiple factors including the physical and chemical state (or speciation) of metals and the range of processes, some of which can be seasonal, that cause mobilization of metals. As a result, it is particularly important to understand metal speciation (National Research Council, 2005) and the link between speciation and the rates of metal migration and the impact of natural or engineered variations in flow, biological activity or water chemistry.

  3. Cryoconite and Ice-bubble Microbial Ecosystems in Antarctica

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    During the Antarctica 2000 Expedition samples of rocks and ice bubbles entrained in ice were collected from the blue ice fields near the Moulton Escarpment of the Thiel Mountains (85S, 94W) and the Morris Moraine of the Patriot Hills (80S, 8 1 W) Ellsworth Mountains of Antarctica. Investigation of the microbiota of these cryoconite and ice bubble ecosystems are now being conducted to help refine chemical and morphological biomarkers of potential significance to Astrobiology. The Antarctica 2000 Expedition will be discussed and the preliminary results of the studies of the ice bubble and cryoconite microbial ecosystems discussed. Recent ESEM images of the Antarctic microbiota will be presented a the relevance of ice ecosystems to Astrobiology will be discussed.

  4. Laboratory Studies of Ice Nucleation on Volcanic Ash

    NASA Astrophysics Data System (ADS)

    Tolbert, M. A.; Schill, G. P.; Genareau, K. D.

    2014-12-01

    Ice nucleation on volcanic ash controls both ash aggregation and cloud glaciation, which affect human respiratory health, atmospheric transport, and global climate. We have performed laboratory studies of the depositional and immersion freezing efficiency of three distinct samples of volcanic ash using Raman Microscopy coupled to an environmental cell. Ash from the Fuego (Basaltic Ash, Guatemala), Soufriere Hills (Andesetic Ash, Montserrat), and Taupo (Rhyolitic Ash, New Zealand) volcanoes were chosen to represent different geographical locations and silica content. All ash samples were quantitatively analyzed for both percent crystallinity and mineralogy using X-ray diffraction. We find that all three samples of volcanic ash are excellent depositional ice nuclei, nucleating ice at ice saturation ratios of 1.05 ± 0.1. For immersion freezing, however, only the Taupo ash exhibited efficient heterogeneous ice nucleation activity. Similar to recent studies on mineral dust, we suggest that the mineralogy of volcanic ash may dictate its ice nucleation activity in the immersion mode.

  5. Engaging Hill-Sachs Defects

    PubMed Central

    Burns, David; Chahal, Jaskarndip; Shahrokhi, Shahram; Henry, Patrick; Wasserstein, David; Whyne, Cari; Theodoropoulos, John S.; Ogilvie-Harris, Darrell; Dwyer, Tim

    2016-01-01

    Objectives: Anatomic studies have demonstrated that bipolar glenoid and humeral bone loss have a cumulative impact on shoulder instability, and that these defects may engage in functional positions depending on their size, location, and orientation, potentially resulting in failure of stabilization procedures. Determining which lesions pose a risk for engagement remains a challenge, with arthroscopic assessment and Itoi’s 3DCT based glenoid track method being the accepted approaches at this time. The purpose of this study was to investigate the interaction of humeral and glenoid bone defects on shoulder engagement in a cadaveric model. Two alternative approaches to predicting engagement were evaluated; 1) CT scanning the shoulder in abduction and external rotation 2) measurement of Bankart lesion width and a novel parameter, the intact anterior articular angle (IAAA), on conventional 2D multi-plane reformats. The results of these two approaches were compared to the results obtained using Itoi’s glenoid track method for predicting engagement. Methods: Hill-Sachs and Bony Bankart defects of varying size were created in 12 cadaveric upper limbs, producing 45 bipolar defect combinations. The shoulders were assessed for engagement using cone beam CT in various positions of function, from 30 to 90 degrees of both abduction and external rotation. The humeral and glenoid defects were characterized by measurement of their size, location, and orientation. Diagnostic performance measures for predicting engagement were calculated for both the abduction external rotation scan and 2D IAAA approaches using the glenoid track method as reference standard. Results: Engagement was predicted by Itoi’s glenoid track method in 24 of 45 specimens (53%). The abduction external rotation CT scan performed at 60 degrees of glenohumeral abduction (corresponding to 90 degrees of abduction relative to the trunk) and 90 degrees of external rotation predicted engagement accurately in 43 of

  6. Onomastic Mirroring: "The Closing of the American Mind" by Allan Bloom and "Lives on the Boundary" by Mike Rose.

    ERIC Educational Resources Information Center

    Heit, Karl

    Although Allan Bloom in "The Closing of the American Mind" and Mike Rose in "Lives on the Boundary" reveal an almost endless list of obvious differences of perspective on literacy and higher education in America, both take divergent yet similar routes to create a permanent place for liberal education. Both Bloom and Rose use…

  7. Allan Hills 84025 - The second brachinite, far more differentiated than brachina, and an ultramafic achondritic clast from L chondrite Yamato 75097

    NASA Technical Reports Server (NTRS)

    Warren, P. H.; Kallemeyn, G. W.

    1989-01-01

    New bulk-compositional and petrographic data tend to confirm that dunitic-wehrlitic meteorite ALH84025 is a second brachinite. It is suggested here that ALH84025 originated as an olivine heteradcumulate, whereas Brachina, or ALH84025, originated as an olivine orthocumulate. The tendency for pyroxenes among brachinites to be high-Ca may be a consequence of a relatively low MgO/FeO ratio, and/or high Na/Ca and K/Ca ratios in the bulk parent body. New data for a 2.5-cm dunite-melatroctolite clast from L6 chondrite Y75097 are reported. This clast has experience depletion of middle REE, except for a large (+) Eu anomaly. The clast as a whole is enriched in phosphates, but almost exclusively in its least-metamorphosed 'core' portion, whereas the analyzed samples represent phosphate-poor portions. It is suggested that this bizarre assemblage probably originated as an achondrite containing cumulus olivine, plagioclase, and phosphate, not necessarily all from a single igneous source rock.

  8. A Shocked Presolar Crystalline Olivine Within the Fine Grained Rim of an Allan Hills A77307 Chondrule: A Tracer for Parent Body Processes?

    NASA Astrophysics Data System (ADS)

    Stojic, A. N.; Leitner, J.; Hoppe, P.; Brenker, F. E.

    2016-08-01

    We report on a presolar crystalline olivine grain characterised by ATEM in its hosting fine grained rim, a large surrounding electron transparent area enables insights into alteration processes linked to parent body and terrestrial processing.

  9. Pesticides, Neurodevelopmental Disagreement, and Bradford Hill's Guidelines.

    PubMed

    Shrader-Frechette, Kristin; ChoGlueck, Christopher

    2016-06-27

    Neurodevelopmental disorders such as autism affect one-eighth of all U.S. newborns. Yet scientists, accessing the same data and using Bradford-Hill guidelines, draw different conclusions about the causes of these disorders. They disagree about the pesticide-harm hypothesis, that typical United States prenatal pesticide exposure can cause neurodevelopmental damage. This article aims to discover whether apparent scientific disagreement about this hypothesis might be partly attributable to questionable interpretations of the Bradford-Hill causal guidelines. Key scientists, who claim to employ Bradford-Hill causal guidelines, yet fail to accept the pesticide-harm hypothesis, fall into errors of trimming the guidelines, requiring statistically-significant data, and ignoring semi-experimental evidence. However, the main scientists who accept the hypothesis appear to commit none of these errors. Although settling disagreement over the pesticide-harm hypothesis requires extensive analysis, this article suggests that at least some conflicts may arise because of questionable interpretations of the guidelines.

  10. Elk Hills: still out in front

    SciTech Connect

    Rintoul, B.

    1982-07-01

    The producing history and capacity of the Elk Hills Oil and Gas Fields in California are described. Developments in the field are discussed, including waterflooding. The field presently produces ca. 160,000 bpd of oil and 350 mmcfd of natural gas. Gas liquids production totals ca. 683,000 gal/day. Waterflooding is expected to pay an increasingly important role in the production of crude oil. Steaming techniques also are viewed with favor after analysis of results of pilot projects. Exploratory develoment in Elk Hills also continues.

  11. The MCT8 thyroid hormone transporter and Allan--Herndon--Dudley syndrome

    PubMed Central

    Schwartz, Charles E.; Stevenson, Roger E.

    2007-01-01

    Thyroid hormone is essential for the proper development and function of the brain. The active form of thyroid hormone is T3, which binds to nuclear receptors. Recently, a transporter specific for T3, MCT8 (monocarboxylate transporter 8) was identified. MCT8 is highly expressed in liver and brain. The gene is located in Xq13 and mutations in MCT8 are responsible for an X-linked condition, Allan--Herndon--Dudley syndrome (AHDS). This syndrome is characterized by congenital hypotonia that progresses to spasticity with severe psychomotor delays. Affected males also present with muscle hypoplasia, generalized muscle weakness, and limited speech. Importantly, these patients have elevated serum levels of free T3, low to below normal serum levels of free T4, and levels of thyroid stimulating hormone that are within the normal range. This constellation of measurements of thyroid function enables quick screening for AHDS in males presenting with mental retardation, congenital hypotonia, and generalized muscle weakness. PMID:17574010

  12. The MCT8 thyroid hormone transporter and Allan-Herndon-Dudley syndrome.

    PubMed

    Schwartz, Charles E; Stevenson, Roger E

    2007-06-01

    Thyroid hormone is essential for the proper development and function of the brain. The active form of thyroid hormone is T(3), which binds to nuclear receptors. Recently, a transporter specific for T(3), MCT8 (monocarboxylate transporter 8) was identified. MCT8 is highly expressed in liver and brain. The gene is located in Xq13 and mutations in MCT8 are responsible for an X-linked condition, Allan-Herndon-Dudley syndrome (AHDS). This syndrome is characterized by congenital hypotonia that progresses to spasticity with severe psychomotor delays. Affected males also present with muscle hypoplasia, generalized muscle weakness, and limited speech. Importantly, these patients have elevated serum levels of free T(3), low to below normal serum levels of free T(4), and levels of thyroid stimulating hormone that are within the normal range. This constellation of measurements of thyroid function enables quick screening for AHDS in males presenting with cognitive impairment, congenital hypotonia, and generalized muscle weakness.

  13. Application of Fast Dynamic Allan Variance for the Characterization of FOGs-Based Measurement While Drilling.

    PubMed

    Wang, Lu; Zhang, Chunxi; Gao, Shuang; Wang, Tao; Lin, Tie; Li, Xianmu

    2016-12-07

    The stability of a fiber optic gyroscope (FOG) in measurement while drilling (MWD) could vary with time because of changing temperature, high vibration, and sudden power failure. The dynamic Allan variance (DAVAR) is a sliding version of the Allan variance. It is a practical tool that could represent the non-stationary behavior of the gyroscope signal. Since the normal DAVAR takes too long to deal with long time series, a fast DAVAR algorithm has been developed to accelerate the computation speed. However, both the normal DAVAR algorithm and the fast algorithm become invalid for discontinuous time series. What is worse, the FOG-based MWD underground often keeps working for several days; the gyro data collected aboveground is not only very time-consuming, but also sometimes discontinuous in the timeline. In this article, on the basis of the fast algorithm for DAVAR, we make a further advance in the fast algorithm (improved fast DAVAR) to extend the fast DAVAR to discontinuous time series. The improved fast DAVAR and the normal DAVAR are used to responsively characterize two sets of simulation data. The simulation results show that when the length of the time series is short, the improved fast DAVAR saves 78.93% of calculation time. When the length of the time series is long ( 6 × 10 5 samples), the improved fast DAVAR reduces calculation time by 97.09%. Another set of simulation data with missing data is characterized by the improved fast DAVAR. Its simulation results prove that the improved fast DAVAR could successfully deal with discontinuous data. In the end, a vibration experiment with FOGs-based MWD has been implemented to validate the good performance of the improved fast DAVAR. The results of the experience testify that the improved fast DAVAR not only shortens computation time, but could also analyze discontinuous time series.

  14. Application of Fast Dynamic Allan Variance for the Characterization of FOGs-Based Measurement While Drilling

    PubMed Central

    Wang, Lu; Zhang, Chunxi; Gao, Shuang; Wang, Tao; Lin, Tie; Li, Xianmu

    2016-01-01

    The stability of a fiber optic gyroscope (FOG) in measurement while drilling (MWD) could vary with time because of changing temperature, high vibration, and sudden power failure. The dynamic Allan variance (DAVAR) is a sliding version of the Allan variance. It is a practical tool that could represent the non-stationary behavior of the gyroscope signal. Since the normal DAVAR takes too long to deal with long time series, a fast DAVAR algorithm has been developed to accelerate the computation speed. However, both the normal DAVAR algorithm and the fast algorithm become invalid for discontinuous time series. What is worse, the FOG-based MWD underground often keeps working for several days; the gyro data collected aboveground is not only very time-consuming, but also sometimes discontinuous in the timeline. In this article, on the basis of the fast algorithm for DAVAR, we make a further advance in the fast algorithm (improved fast DAVAR) to extend the fast DAVAR to discontinuous time series. The improved fast DAVAR and the normal DAVAR are used to responsively characterize two sets of simulation data. The simulation results show that when the length of the time series is short, the improved fast DAVAR saves 78.93% of calculation time. When the length of the time series is long (6×105 samples), the improved fast DAVAR reduces calculation time by 97.09%. Another set of simulation data with missing data is characterized by the improved fast DAVAR. Its simulation results prove that the improved fast DAVAR could successfully deal with discontinuous data. In the end, a vibration experiment with FOGs-based MWD has been implemented to validate the good performance of the improved fast DAVAR. The results of the experience testify that the improved fast DAVAR not only shortens computation time, but could also analyze discontinuous time series. PMID:27941600

  15. Allan-Herndon-Dudley Syndrome and the Monocarboxylate Transporter 8 (MCT8) Gene

    PubMed Central

    Schwartz, Charles E. ; May, Melanie M. ; Carpenter, Nancy J. ; Rogers, R. Curtis ; Martin, Judith ; Bialer, Martin G. ; Ward, Jewell ; Sanabria, Javier ; Marsa, Silvana ; Lewis, James A. ; Echeverri, Roberto ; Lubs, Herbert A. ; Voeller, Kytja ; Simensen, Richard J. ; Stevenson, Roger E. 

    2005-01-01

    Allan-Herndon-Dudley syndrome was among the first of the X-linked mental retardation syndromes to be described (in 1944) and among the first to be regionally mapped on the X chromosome (in 1990). Six large families with the syndrome have been identified, and linkage studies have placed the gene locus in Xq13.2. Mutations in the monocarboxylate transporter 8 gene (MCT8) have been found in each of the six families. One essential function of the protein encoded by this gene appears to be the transport of triiodothyronine into neurons. Abnormal transporter function is reflected in elevated free triiodothyronine and lowered free thyroxine levels in the blood. Infancy and childhood in the Allan-Herndon-Dudley syndrome are marked by hypotonia, weakness, reduced muscle mass, and delay of developmental milestones. Facial manifestations are not distinctive, but the face tends to be elongated with bifrontal narrowing, and the ears are often simply formed or cupped. Some patients have myopathic facies. Generalized weakness is manifested by excessive drooling, forward positioning of the head and neck, failure to ambulate independently, or ataxia in those who do ambulate. Speech is dysarthric or absent altogether. Hypotonia gives way in adult life to spasticity. The hands exhibit dystonic and athetoid posturing and fisting. Cognitive development is severely impaired. No major malformations occur, intrauterine growth is not impaired, and head circumference and genital development are usually normal. Behavior tends to be passive, with little evidence of aggressive or disruptive behavior. Although clinical signs of thyroid dysfunction are usually absent in affected males, the disturbances in blood levels of thyroid hormones suggest the possibility of systematic detection through screening of high-risk populations. PMID:15889350

  16. Allan-Herndon-Dudley syndrome and the monocarboxylate transporter 8 (MCT8) gene.

    PubMed

    Schwartz, Charles E; May, Melanie M; Carpenter, Nancy J; Rogers, R Curtis; Martin, Judith; Bialer, Martin G; Ward, Jewell; Sanabria, Javier; Marsa, Silvana; Lewis, James A; Echeverri, Roberto; Lubs, Herbert A; Voeller, Kytja; Simensen, Richard J; Stevenson, Roger E

    2005-07-01

    Allan-Herndon-Dudley syndrome was among the first of the X-linked mental retardation syndromes to be described (in 1944) and among the first to be regionally mapped on the X chromosome (in 1990). Six large families with the syndrome have been identified, and linkage studies have placed the gene locus in Xq13.2. Mutations in the monocarboxylate transporter 8 gene (MCT8) have been found in each of the six families. One essential function of the protein encoded by this gene appears to be the transport of triiodothyronine into neurons. Abnormal transporter function is reflected in elevated free triiodothyronine and lowered free thyroxine levels in the blood. Infancy and childhood in the Allan-Herndon-Dudley syndrome are marked by hypotonia, weakness, reduced muscle mass, and delay of developmental milestones. Facial manifestations are not distinctive, but the face tends to be elongated with bifrontal narrowing, and the ears are often simply formed or cupped. Some patients have myopathic facies. Generalized weakness is manifested by excessive drooling, forward positioning of the head and neck, failure to ambulate independently, or ataxia in those who do ambulate. Speech is dysarthric or absent altogether. Hypotonia gives way in adult life to spasticity. The hands exhibit dystonic and athetoid posturing and fisting. Cognitive development is severely impaired. No major malformations occur, intrauterine growth is not impaired, and head circumference and genital development are usually normal. Behavior tends to be passive, with little evidence of aggressive or disruptive behavior. Although clinical signs of thyroid dysfunction are usually absent in affected males, the disturbances in blood levels of thyroid hormones suggest the possibility of systematic detection through screening of high-risk populations.

  17. 3. GENERAL VIEW DOWN EAST HILLS DRIVE, BUILDING 20 (ONE ...

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

    3. GENERAL VIEW DOWN EAST HILLS DRIVE, BUILDING 20 (ONE BEDROOM) AND BUILDING 21 (TWO/THREE BEDROOM); ACTIVITY CENTER IN REAR, FACING NORTHEAST. - Aluminum City Terrace, East Hill Drive, New Kensington, Westmoreland County, PA

  18. OVERVIEW OF GOLD HILL MILL, ROAD, AND WARM SPRINGS CAMP ...

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

    OVERVIEW OF GOLD HILL MILL, ROAD, AND WARM SPRINGS CAMP BUILDINGS, LOOKING SOUTH SOUTHEAST. THE FUNCTION OF THE FLAT AREA AT CENTER RIGHT IS UNKNOWN. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  19. Bursting money bins, the ice and water structure

    NASA Astrophysics Data System (ADS)

    Bagnoli, Franco

    2015-05-01

    In the classic comics by Carl Barks, "The Big Bin on Killmotor Hill" [1], Uncle Scrooge, trying to defend his money bin from the Beagle Boys, follows a suggestion by Donald Duck, and fills the bin with water. Unfortunately, that night is going be the coldest one in the history of Ducksburg. The water freezes, bursting the "ten-foot walls'' of the money bin, and finally the gigantic cube of ice and dollars slips down the hill up to the Beagle Boys lot.

  20. Segment lengths influence hill walking strategies.

    PubMed

    Sheehan, Riley C; Gottschall, Jinger S

    2014-08-22

    Segment lengths are known to influence walking kinematics and muscle activity patterns. During level walking at the same speed, taller individuals take longer, slower strides than shorter individuals. Based on this, we sought to determine if segment lengths also influenced hill walking strategies. We hypothesized that individuals with longer segments would display more joint flexion going uphill and more extension going downhill as well as greater lateral gastrocnemius and vastus lateralis activity in both directions. Twenty young adults of varying heights (below 155 cm to above 188 cm) walked at 1.25 m/s on a level treadmill as well as 6° and 12° up and downhill slopes while we collected kinematic and muscle activity data. Subsequently, we ran linear regressions for each of the variables with height, leg, thigh, and shank length. Despite our population having twice the anthropometric variability, the level and hill walking patterns matched closely with previous studies. While there were significant differences between level and hill walking, there were few hill walking variables that were correlated with segment length. In support of our hypothesis, taller individuals had greater knee and ankle flexion during uphill walking. However, the majority of the correlations were between tibialis anterior and lateral gastrocnemius activities and shank length. Contrary to our hypothesis, relative step length and muscle activity decreased with segment length, specifically shank length. In summary, it appears that individuals with shorter segments require greater propulsion and toe clearance during uphill walking as well as greater braking and stability during downhill walking.

  1. General Education at UNC-Chapel Hill

    ERIC Educational Resources Information Center

    Schalin, Jay; Robinson, Jenna Ashley

    2013-01-01

    The general education program at UNC-Chapel Hill has abandoned the concept of a core curriculum. Instead, students choose their "required" classes from lists of thousands of courses that may be as narrow and idiosyncratic as Love, Sex and Marriage in Soviet Culture (RUSS 277) or The Gardens, Shrines and Temples of Japan (ASIA 586).…

  2. ENHANCED REMEDIATION DEMONSTRATIONS AT HILL AFB: INTRODUCTION

    EPA Science Inventory

    Nine enhanced aquifer remediation technologies were demonstrated side-by-side at a Hill Air Force Base Chemical Disposal Pit/Fire Training Area site. The demonstrations were performed inside 3 x 5 m cells isolated from the surrounding shallow aquifer by steel piling. The site w...

  3. The House on the Hill Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2011-01-01

    In this article, the author suggests a classroom challenge that will engage students in designing a house on the hill. He suggests teachers ask a local builder to come to the school to discuss the kinds of concerns that must be dealt with when building homes in cold environments. The use of dioramas and cardboard scale models would be very useful…

  4. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Approved Maps. The appropriate maps for determining the boundaries of the Rattlesnake Hills viticultural area are eight United States Geological Survey 1:24,000 scale topographic maps. They are titled: (1.... The area's boundary is defined as follows: (1) The beginning point is on the Yakima East map at...

  5. Andoyer construction for Hill and Delaunay variables

    NASA Astrophysics Data System (ADS)

    Laskar, Jacques

    2017-03-01

    Andoyer variables are well known for the study of rotational dynamics. These variables were derived by Andoyer through a procedure that can be also used to obtain the Hill variables of the Kepler problem. Andoyer construction can also forecast the Delaunay variables which canonicity is then obtained without the use of a generating function.

  6. Ocean Hill-Brownsville, 40 Years Later

    ERIC Educational Resources Information Center

    Kahlenberg, Richard D.

    2008-01-01

    Forty years ago--on May 9, 1968--the local school board in Brooklyn's black ghetto of Ocean Hill-Brownsville sent telegrams to 19 unionized educators, informing them that their employment in the district was terminated. Eighteen were white. One black teacher was mistakenly included on the list, but reinstated almost immediately after the error was…

  7. An Unlikely Student Hits Capitol Hill

    ERIC Educational Resources Information Center

    Hoover, Eric

    2009-01-01

    Todd Sollar, a laid-off autoworker from Ohio who is studying for an associate degree in engineering at Sinclair Community College, in Dayton, OH, went to Capitol Hill to help educate lawmakers about the importance of including support for community colleges in the economic-stimulus bill. Mr. Sollar came to Washington with Sinclair's president, and…

  8. The hill forts and castle mounds in Lithuania: interaction between geodiversity and human-shaped landscape

    NASA Astrophysics Data System (ADS)

    Skridlaite, Grazina; Guobyte, Rimante; Satkunas, Jonas

    2015-04-01

    Lithuania is famous for its abundant, picturesque hill forts and castle mounds of natural origin. In Lithuania as well as in whole Europe the fortified hills were used as the society dwelling place since the beginning of the Late Bronze Age. Their importance increased when Livonian and Teutonic Orders directed a series of military campaigns against Lithuania with the aim of expansion of Christianity in the region at the end of 1st millennium AD, and they were intensively used till the beginning of the 15th c. when most of them were burned down during fights with the Orders or just abandoned due to the changing political and economical situation. What types of the geodiversity were used for fortified dwellings? The choice in a particular area depended on a variety of geomorphology left behind the retreating ice sheets. High spots dominating their surroundings were of prime interest. In E and SE Lithuania, the Baltic Upland hills marking the eastern margin of the last Weichselian glacier hosted numerous fortified settlements from the end of 2nd millennium BC to the Medieval Ages (Narkunai, Velikuskes etc). In W Lithuania, plateau-like hills of the insular Samogitian Upland had been repeatedly fortified from the beginning of 1st millennium AD to the 14th century (Satrija, Medvegalis etc). Chains of hill forts and castle mounds feature the slopes of glaciofluvial valleys of Nemunas, Neris and other rivers where the slopes were dissected by affluent rivulets and ravines and transformed into isolated, well protected hills (Kernave, Punia, Veliuona etc). Peninsulas and headlands formed by the erosion of fluvial and lacustrine deposits were used in the lowlands, e.g. in central and N Lithuania (Paberze, Mezotne etc). How much the landscape was modified for defense purposes? Long-term erosion and overgrowing vegetation damaged the former fortified sites, however some remains and the archeological excavations allowed their reconstruction. The fortified Bronze Age settlements

  9. 3. HYDE STREET HILL: View to north looking down the ...

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

    3. HYDE STREET HILL: View to north looking down the Hyde Street hill from Lombard Street. The steepest hill on the present cable railway system, this grade exceeds 20%. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

  10. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...). (3) “Los Alamos, Calif.,” edition of 1959. (4) “Santa Rosa Hills, Calif.,” edition of 1959... Hills viticultural area is located in Santa Barbara County, California. The boundary is as follows: (1... the heart of the Santa Rosa Land Grant, T.7N., R. 32W, on the Santa Rosa Hills, Calif., Quadrangle...

  11. View of south boundary of Easter Hill project site, former ...

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

    View of south boundary of Easter Hill project site, former right of way for Hoffman Boulevard. Note reconstructed Easter Hill Building No. 6 at rear. Looking east - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  12. 78 FR 65962 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of cancellation of meeting of the Black Hills National Forest Advisory Board. SUMMARY: The U. S. Department of Agriculture, Forest Service, Black Hills National Forest cancelled the October 16, 2013 meeting of the...

  13. 77 FR 22755 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Black Hills National Forest Advisory Board AGENCY: USDA Forest Service. ACTION: Notice of cancellation of meetings of the Black Hills National Forest Advisory Board. SUMMARY: The U. S. Department of Agriculture, Forest Service, Black Hills National Forest was required...

  14. Paleotopography of Husband Hill and the West Spur of the Columbia Hills, Gusev Crater, Mars

    NASA Astrophysics Data System (ADS)

    Cole, S. B.; Watters, W. A.; Aron, F. A.; Squyres, S.

    2012-12-01

    From June 2004 through March 2010, Spirit conducted a detailed campaign examining the Columbia Hills of Gusev Crater. The Hills are an irregular, nearly-triangular edifice of uncertain origin, spanning ~8.4 km in the northerly direction by ~4.5 km in the easterly direction, and are embayed by the basaltic plains that fill the floor of Gusev Crater. The topography is as irregular as the perimeter, cut by numerous valleys of varying lengths, widths, and directional trends. Along its traverse, Spirit examined several rock classes as defined by elemental abundances from the Alpha Particle X-ray Spectrometer (APXS). Unlike the Gusev Plains, the rocks of the Columbia Hills show extensive evidence of aqueous alteration. In addition to mineralogical and chemical investigations, Spirit's stereo panoramic (Pancam) and navigation (Navcam) cameras obtained over 7,000 images of the West Spur of the Columbia Hills and Husband Hill, the highest peak. This dataset includes stereo coverage of several outcrop exposures with apparent bedding. In this analysis, we reconstruct a paleo-Digital Elevation Model (paleo-DEM) of the West Spur and Husband Hill based on stereo image data from the Mars Exploration Rover Spirit. We have performed detailed structural and stratigraphic measurements of the outcrops Spirit observed on its traverse across the West Spur and Husband Hill, using digital terrain models derived from Pancam and Navcam data. We compare outcrop bedding orientations to local topography as determined by the HiRISE DEM. While bedding orientations do not conform to the current topography, outcrops within local geographic regions exhibit conformable bedding orientations both within and across the rock classes defined by composition. Assuming that the bedding planes are in-place and were conformable to the local topography at the time of deposition, we reconstruct the ancient topography of the West Spur and Husband Hill.

  15. Operation IceBridge: Sea Ice Interlude

    NASA Video Gallery

    Sea ice comes in an array of shapes and sizes and has its own ephemeral beauty. Operation IceBridge studies sea ice at both poles, and also runs across interesting formations en route to other targ...

  16. Structure, stratigraphy, and origin of Husband Hill, Columbia Hills, Gusev Crater, Mars

    USGS Publications Warehouse

    McCoy, T.J.; Sims, M.; Schmidt, M.E.; Edwards, L.; Tornabene, L.L.; Crumpler, L.S.; Cohen, B. A.; Soderblom, L.A.; Blaney, D.L.; Squyres, S. W.; Arvidson, R. E.; Rica, J.W.; Treguier, E.; d'Uston, C.; Grant, J. A.; McSween, H.Y.; Golombek, M.P.; Haldemann, A.F.C.; de Souza, P.A.

    2008-01-01

    The strike and dip of lithologic units imaged in stereo by the Spirit rover in the Columbia Hills using three-dimensional imaging software shows that measured dips (15-32??) for bedding on the main edifice of the Columbia Hill are steeper than local topography (???8-10??). Outcrops measured on West Spur are conformable in strike with shallower dips (7-15??) than observed on Husband Hill. Dips are consistent with observed strata draping the Columbia Hills. Initial uplift was likely related either to the formation of the Gusev Crater central peak or ring or through mutual interference of overlapping crater rims. Uplift was followed by subsequent draping by a series of impact and volcaniclastic materials that experienced temporally and spatially variable aqueous infiltration, cementation, and alteration episodically during or after deposition. West Spur likely represents a spatially isolated depositional event. Erosion by a variety of processes, including mass wasting, removed tens of meters of materials and formed the Tennessee Valley primarily after deposition. This was followed by eruption of the Adirondack-class plains basalt lava flows which embayed the Columbia Hills. Minor erosion, impact, and aeolian processes have subsequently modified the Columbia Hills. Copyright 2008 by the American Geophysical Union.

  17. Lateglacial geomorphology in the Tweedsmuir Hills, Scotland - Implications for retreat patterns, glacier reconstruction and chronology.

    NASA Astrophysics Data System (ADS)

    Pearce, D.; Rea, B.; McDougall, D.

    2012-04-01

    The Tweedsmuir Hills, Southern Uplands, Scotland, contain excellent assemblages of glacial landforms, including hummocky moraine, classically associated with a Lateglacial deglaciation (c. 14.7 - 11.7 cal. ka BP) in the UK. Although initially documented in 1855, a detailed systematic geomorphological investigation has never been undertaken in the region, meaning reconstructions are patchy, outdated and lacking chronological control. This has resulted in conflicting styles of glaciation being inferred, with both plateau icefield and valley glaciers reconstructed in the Tweedsmuir Hills. Importantly, comprehensive numerical modelling experiments for the period, c. 38 -10.4 ka BP, predict a significant body of ice for the Tweedsmuir Hills at the onset and throughout the Younger Dryas (c. 12.9 - 11.7 cal. ka. BP). Field data, which at present, are missing means that the numerical modelling remains untested. Given the emerging evidence that ice-masses survived, during or throughout the Lateglacial in a number of regions in Scotland, the glacial geomorphology and reconstructions for this area will provide a key input of palaeo-glacier data for subsequent investigation of wider patterns of Lateglacial ice-mass distribution and climate gradients across the UK and NW Europe. Geomorphological mapping followed a morphostratigraphic approach using a combination of aerial photos, NEXTMapTM and mapping in the field using a ruggedized tablet PC, with built in GPS and ArcGIS 9.3. The glacial landforms indicate two separate landsystems. The first is characterised by elongate subglacial bedforms overriding the topography, trending SW to NE, suggested to be attributable to the Devensian glaciation. The second landsystem is characterised by closely spaced sharp crested moraines, oblique to the valley axis and confined by the topography, meltwater channels and single terrace systems, which are likely to have formed in a subsequent period of renewed glaciation i.e. Lateglacial. The

  18. Morgan Hill, California Earthquake, April 1984

    USGS Publications Warehouse

    Spall, Henry

    1987-01-01

    The Morgan Hill earthquake, a moderate-size (Mg=6.1, ML =6.2, M=6.2) event, was felt throughout central California on April 24, 1984. The epicenter of the earthquake was located near Halls Valley southwest of Mount Hamilton, and the event is presumed to have occurred on the Calaveras fault. Damage, however, was concentrated near the south end of the Anderson Reservoir and in the town of Morgan Hill. A preliminary assessment by the California Office of Emergency Services estimated damage to private property at \\$7.0 million and to local-government facilities at \\$0.5 million, for a total of \\$7.5 million in damage. 

  19. Gossan Hill, Victoria Island, Northwest Territories: An analogue for mine waste reactions within permafrost and implication for the subsurface mineralogy of Mars

    NASA Astrophysics Data System (ADS)

    Peterson, Ronald C.; Williamson, Marie-Claude; Rainbird, Robert H.

    2014-08-01

    Gossan Hill is located within the Minto Inlier in central Victoria Island, Northwest Territories (N 71.36697°, W 114.95155°). A study of the mineralogical associations and geological setting of this deposit indicates that it is an arrested hydrothermal system frozen in permafrost. From above, the hill stands out because of the topographic relief of 75 m and the orange-brown color of the surficial material. The surface of the hill is marked by areas of concentric color zonation up to 3 m across, with light gray centers surrounded by a yellow-orange ring that is surrounded by an orange-brown color that covers the rest of the surface of the hill. Trenches dug into these areas reveal that the central zone contains quartz and pyrite +/- native sulfur in a loose aggregate of sand-sized grains. This central area is surrounded by a zone dominated by gypsum and quartz with some jarosite. Beyond this, the surrounding surface consists of quartz, hematite, and amorphous iron oxides. The radial arrangement of the mineral assemblage indicates an increase in oxidation of sulfur from the center outward. Analysis of isotopic composition of the sulfur indicates the source of sulfur could be the underlying strata. The hill is underlain by inter-bedded carbonate and sulfate-evaporite sedimentary rocks of the Kilian formation in the upper part of the Neoproterozoic Shaler Super group. The sedimentary rocks were intruded by diabase sills of the 720 Ma Franklin igneous event, which crop out 2 km to the south of Gossan Hill. The soft friable nature of the deposit and the topographic relief of the hill indicate a post-glacial (Pleistocene) age of formation. Permafrost has maintained the disequilibrium mineral assemblage since the cessation of fluid flow. Extraction of the permafrost ice from the central zone yields a liquid with a pH of 2.3. The observed long-term persistence of pyrite encased within the acidic permafrost indicates that oxidation and dissolution reactions common in mine

  20. Hill Ciphers over Near-Fields

    ERIC Educational Resources Information Center

    Farag, Mark

    2007-01-01

    Hill ciphers are linear codes that use as input a "plaintext" vector [p-right arrow above] of size n, which is encrypted with an invertible n x n matrix E to produce a "ciphertext" vector [c-right arrow above] = E [middle dot] [p-right arrow above]. Informally, a near-field is a triple [left angle bracket]N; +, *[right angle bracket] that…

  1. Autonomous Legged Hill and Stairwell Ascent

    DTIC Science & Technology

    2011-11-01

    environments with little burden to a human operator. Keywords: autonomous robot, hill climbing, stair climbing, sequential composition, hexapod, self...simulation studies [11], with almost all empirical work confined to the traversal of a single flight and yaw control on the stairs (summarized in [4]). The...only prior report we have found documenting empirical work over multiple flights of stairs assumed a very specific, simple landing geometry [12]; we

  2. The Rocks of the Columbia Hills

    NASA Technical Reports Server (NTRS)

    Squyres, Steven W.; Arvidson, Raymond E.; Blaney, Diana L.; Clark, Benton C.; Crumpler, Larry; Farrand, William H.; Gorevan, Stephen; Herkenhoff, Kenneth; Hurowitz, Joel; Kusack, Alastair; McSween, Harry Y.; Ming, Douglas W.; Morris, Richard V.; Ruff, Steven W.; Wang, Alian; Yen, Albert

    2006-01-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly-sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously-altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly-sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands, and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks, and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present.

  3. Miocene cercopithecoidea from the Tugen Hills, Kenya.

    PubMed

    Gilbert, Christopher C; Goble, Emily D; Hill, Andrew

    2010-11-01

    Miocene to Pleistocene fossiliferous sediments in the Tugen Hills span the time period from at least 15.5 Ma to 0.25 Ma, including time periods unknown or little known elsewhere in Africa. Consequently, the Tugen Hills deposits hold the potential to inform us about crucial phylogenetic events in African faunal evolution and about long-term environmental change. Among the specimens collected from this region are a number of discoveries already important to the understanding of primate evolution. Here, we describe additional cercopithecoid material from the Miocene deposits in the Tugen Hills sequence, including those from securely dated sites in the Muruyur Beds (16-13.4 Ma), the Mpesida Beds (7-6.2 Ma) and the Lukeino Formation (∼ 6.2-5.7 Ma). We also evaluate previously described material from the Ngorora Formation (13-8.8 Ma). Identified taxa include Victoriapithecidae gen. et sp. indet., cf. Parapapio lothagamensis, and at least two colobines. Specimens attributed to cf. Pp. lothagamensis would extend the species' geographic range beyond its type locality. In addition, we describe specimens sharing derived characters with modern African colobines (Tribe: Colobina), a finding that is congruent with previous molecular estimates of colobine divergence dates. These colobine specimens represent some of the earliest known members of the modern African colobine radiation and, in contrast to previous hypotheses, suggest that early African colobines were mainly arboreal and that semi-terrestrial Late Miocene and Plio-Pleistocene colobine taxa were secondarily derived in their locomotor adaptations.

  4. Airborne laser swath mapping of the Denton Hills, Transantarctic Mountains, Antarctica: Applications for structural and glacial geomorphic mapping

    USGS Publications Warehouse

    Wilson, Terry; Csathó, Beata

    2007-01-01

    High-resolution digital elevation data acquired by airborne laser scanning (ALS) for the Denton Hills, along the coastal foothills of the Royal Society Range, Transantarctic Mountains, are examined for applications to bedrock and glacial geomorphic mapping. Digital elevation models (DEMs), displayed as shaded-relief images and slope maps, portray geomorphic landscape features in unprecedented detail across the region. Structures of both ductile and brittle origin, ranging in age from the Paleozoic to the Quaternary, can be mapped from the DEMs. Glacial features, providing a record of the limits of grounded ice, of lake paleoshorelines, and of proglacial lake-ice conveyor deposits, are also prominent on the DEMs. The ALS-derived topographic data have great potential for a range of mapping applications in regions of ice-free terrain in Antarctica

  5. Confidence Hills Mineralogy and Chemin Results from Base of Mt. Sharp, Pahrump Hills, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Cavanagh, P. D.; Bish, D. L.; Blake, D. F.; Vaniman, D. T.; Morris, R. V.; Ming, D. W.; Rampe, E. B.; Achilles, C. N.; Chipera, S. J.; Treiman, A. H.; Downs, R. T.; Morrison, S. M.; Fendrich, K. V.; Yen, A. S.; Grotzinger, J.; Crisp, J. A.; Bristow, T. F.; Sarrazin, P. C.; Farmer, J. D.; Des Marais, D. J.; Stolper, E. M.; Morookian, J. M.; Wilson, M. A.; Spanovich, N.; Anderson, R. C.

    2015-01-01

    The Mars Science Laboratory (MSL) rover Curiosity recently completed its fourth drill sampling of sediments on Mars. The Confidence Hills (CH) sample was drilled from a rock located in the Pahrump Hills region at the base of Mt. Sharp in Gale Crater. The CheMin X-ray diffractometer completed five nights of analysis on the sample, more than previously executed for a drill sample, and the data have been analyzed using Rietveld refinement and full-pattern fitting to determine quantitative mineralogy. Confidence Hills mineralogy has several important characteristics: 1) abundant hematite and lesser magnetite; 2) a 10 angstrom phyllosilicate; 3) multiple feldspars including plagioclase and alkali feldspar; 4) mafic silicates including forsterite, orthopyroxene, and two types of clinopyroxene (Ca-rich and Ca-poor), consistent with a basaltic source; and 5) minor contributions from sulfur-bearing species including jarosite.

  6. Application of the Allan Variance to Time Series Analysis in Astrometry and Geodesy: A Review.

    PubMed

    Malkin, Zinovy

    2016-04-01

    The Allan variance (AVAR) was introduced 50 years ago as a statistical tool for assessing the frequency standards deviations. For the past decades, AVAR has increasingly been used in geodesy and astrometry to assess the noise characteristics in geodetic and astrometric time series. A specific feature of astrometric and geodetic measurements, as compared with clock measurements, is that they are generally associated with uncertainties; thus, an appropriate weighting should be applied during data analysis. In addition, some physically connected scalar time series naturally form series of multidimensional vectors. For example, three station coordinates time series X, Y, and Z can be combined to analyze 3-D station position variations. The classical AVAR is not intended for processing unevenly weighted and/or multidimensional data. Therefore, AVAR modifications, namely weighted AVAR (WAVAR), multidimensional AVAR (MAVAR), and weighted multidimensional AVAR (WMAVAR), were introduced to overcome these deficiencies. In this paper, a brief review is given of the experience of using AVAR and its modifications in processing astrogeodetic time series.

  7. Twenty-Five Years of Applications of the Modified Allan Variance in Telecommunications.

    PubMed

    Bregni, Stefano

    2016-04-01

    The Modified Allan Variance (MAVAR) was originally defined in 1981 for measuring frequency stability in precision oscillators. Due to its outstanding accuracy in discriminating power-law noise, it attracted significant interest among telecommunications engineers since the early 1990s, when it was approved as a standard measure in international standards, redressed as Time Variance (TVAR), for specifying the time stability of network synchronization signals and of equipment clocks. A dozen years later, the usage of MAVAR was also introduced for Internet traffic analysis to estimate self-similarity and long-range dependence. Further, in this field, it demonstrated superior accuracy and sensitivity, better than most popular tools already in use. This paper surveys the last 25 years of progress in extending the field of application of the MAVAR in telecommunications. First, the rationale and principles of the MAVAR are briefly summarized. Its adaptation as TVAR for specification of timing stability is presented. The usage of MAVAR/TVAR in telecommunications standards is reviewed. Examples of measurements on real telecommunications equipment clocks are presented, providing an overview on their actual performance in terms of MAVAR. Moreover, applications of MAVAR to network traffic analysis are surveyed. The superior accuracy of MAVAR in estimating long-range dependence is emphasized by highlighting some remarkable practical examples of real network traffic analysis.

  8. THE DEAD-LIVING-MOTHER: MARIE BONAPARTE'S INTERPRETATION OF EDGAR ALLAN POE'S SHORT STORIES.

    PubMed

    Obaid, Francisco Pizarro

    2016-06-01

    Princess Marie Bonaparte is an important figure in the history of psychoanalysis, remembered for her crucial role in arranging Freud's escape to safety in London from Nazi Vienna, in 1938. This paper connects us to Bonaparte's work on Poe's short stories. Founded on concepts of Freudian theory and an exhaustive review of the biographical facts, Marie Bonaparte concluded that the works of Edgar Allan Poe drew their most powerful inspirational force from the psychological consequences of the early death of the poet's mother. In Bonaparte's approach, which was powerfully influenced by her recognition of the impact of the death of her own mother when she was born-an understanding she gained in her analysis with Freud-the thesis of the dead-living-mother achieved the status of a paradigmatic key to analyze and understand Poe's literary legacy. This paper explores the background and support of this hypothesis and reviews Bonaparte's interpretation of Poe's most notable short stories, in which extraordinary female figures feature in the narrative.

  9. Observation, Inference, and Imagination: Elements of Edgar Allan Poe's Philosophy of Science

    NASA Astrophysics Data System (ADS)

    Gelfert, Axel

    2014-03-01

    Edgar Allan Poe's standing as a literary figure, who drew on (and sometimes dabbled in) the scientific debates of his time, makes him an intriguing character for any exploration of the historical interrelationship between science, literature and philosophy. His sprawling `prose-poem' Eureka (1848), in particular, has sometimes been scrutinized for anticipations of later scientific developments. By contrast, the present paper argues that it should be understood as a contribution to the raging debates about scientific methodology at the time. This methodological interest, which is echoed in Poe's `tales of ratiocination', gives rise to a proposed new mode of—broadly abductive—inference, which Poe attributes to the hybrid figure of the `poet-mathematician'. Without creative imagination and intuition, Science would necessarily remain incomplete, even by its own standards. This concern with imaginative (abductive) inference ties in nicely with his coherentism, which grants pride of place to the twin virtues of Simplicity and Consistency, which must constrain imagination lest it degenerate into mere fancy.

  10. Novel SLC16A2 mutations in patients with Allan-Herndon-Dudley syndrome

    PubMed Central

    Shimojima, Keiko; Maruyama, Koichi; Kikuchi, Masahiro; Imai, Ayako; Inoue, Ken; Yamamoto, Toshiyuki

    2016-01-01

    Summary Allan-Herndon-Dudley syndrome (AHDS) is an X-linked disorder caused by impaired thyroid hormone transporter. Patients with AHDS usually exhibit severe motor developmental delay, delayed myelination of the brain white matter, and elevated T3 levels in thyroid tests. Neurological examination of two patients with neurodevelopmental delay revealed generalized hypotonia, and not paresis, as the main neurological finding. Nystagmus and dyskinesia were not observed. Brain magnetic resonance imaging demonstrated delayed myelination in early childhood in both patients. Nevertheless, matured myelination was observed at 6 years of age in one patient. Although the key finding for AHDS is elevated free T3, one of the patients showed a normal T3 level in childhood, misleading the diagnosis of AHDS. Genetic analysis revealed two novel SLC16A2 mutations, p.(Gly122Val) and p.(Gly221Ser), confirming the AHDS diagnosis. These results indicate that AHDS diagnosis is sometimes challenging owing to clinical variability among patients. PMID:27672545

  11. A legacy in 20th-century medicine: Robert Allan Phillips and the taming of cholera.

    PubMed

    Savarino, Stephen J

    2002-09-15

    The legacy of Captain Robert Allan Phillips (1906-1976) was to establish effective, evidence-based rehydration methods for the treatment of cholera. As a Navy Lieutenant at the Rockefeller Institute for Medical Research (New York, New York) during World War II, Phillips developed a field method for the rapid assessment of fluid loss in wounded servicemen. After the war, he championed the establishment of United States Naval Medical Research Unit (NAMRU)-3 (Cairo; 1946) and NAMRU-2 (Taipei; 1955), serving at the helm of both units. Phillips embarked on cholera studies during the 1947 Egyptian cholera epidemic and brought them to maturity at NAMRU-2 (1958-1965), elucidating the pathophysiologic derangements induced by cholera and developing highly efficacious methods of intravenous rehydration. His conception of a simpler cholera treatment was realized in the late 1960s with the development of glucose-based oral rehydration therapy, a monumental breakthrough to which many other investigators made vital contributions. Today, these simple advances have been integrated into everyday medical practice across the globe, saving millions of lives annually.

  12. Oxygen, carbon and U-series isotopes of aragonites from Vestfold Hills, Antarctica: Clues to geochemical processes in subglacial environments

    SciTech Connect

    Aharon, P. )

    1988-09-01

    Aragonites occurring in situ on the gneissic bedrock at Vestfold Hills, an ice-free coastal Antarctic oasis possess morphologic and petrographic characteristics typical of subglacial carbonate precipitates. The {sup 14}C chronology of the samples is invalidated by modern carbon contamination and a {sup 14}C/{sup 12}C reservoir correction of unknown magnitude. In contrast, U and Th isotope analyses suggest that the subglacial deposits can be treated as closed, datable, systems, if allowance is made for the excess {sup 230}Th derived from the small and variable detrital silicate fraction coexisting with the aragonites. The mean {sup 230}Th depositional age of 35,000 {plus minus} 2,000 yrs correlates with late isotope stage 3 of deep sea glacial chronology and represents the time when the Vestfold Hills were partially or completely buried under the advancing East Antarctic ice sheet. The survival of the aragonites following the ice sheet retreat during the Holocene is attributed to the extreme arid climate of the area. The aragonites are anomalously depleted in {sup 18}O and slightly depleted in {sup 13}C relative to SMOW and PDB standards, respectively ({delta}{sup 18}O = 15.7 {plus minus} 0.9{per thousand}; {delta}{sup 13}C = {minus}3.6 {plus minus} 0.4{per thousand}). The melt water with which the aragonites would have equilibrated at 0{degree}C is about 7 to 9{per thousand} more depleted in {sup 18}O relative to the extant basal ice source ({delta}{sup 18}O = {minus}41{per thousand}). Part of this enhanced {sup 18}O deficiency (i.e. 4 to 6{per thousand}) is ascribed to temporal shifts in {delta}{sup 18}O of the Antarctic ice, the rest to isotope effects of the subglacial hydrology. A model of subglacial aragonite precipitation is proposed on the basis of water flow between warm melting zones and cold freezing zones at the ice sheet sole.

  13. Cl-36 in polar ice, rainwater and seawater

    NASA Technical Reports Server (NTRS)

    Finkel, R. C.; Nishiizumi, K.; Elmore, D.; Ferraro, R. D.; Gove, H. E.

    1980-01-01

    Concentrations of the cosmogenic radioisotope Cl-36 in Antarctic ice, rain, and an upper limit of the seawater value are determined using van de Graaff accelerator high energy mass spectrometry. Cl-36 concentrations in Antarctic ice range between 2.5 to 8.7 x 10 to the 6th atoms Cl-36/kg, while those concentrations in samples collected at the Alan Hills ice field locations where meteorites have been brought to the surface by glacial flow and ablation are found to vary by more than a factor of three. This variation is attributed either to the effects of atmospheric mixing and scavenging or to radioactive decay in old ice. The Cl-36 concentration found in a present sample of rainwater is much lower than that reported in samples collected in the early 1960's, suggesting the occurrence of a decrease in the concentration of atmospheric Cl-36 derived from nuclear weapons tests over this time period.

  14. Three-dimensional potential flow over hills and oval mounds

    NASA Technical Reports Server (NTRS)

    Siegel, R.

    1976-01-01

    An analysis was made of the potential flow behavior for an initially uniform flow passing over a single axisymmetric hill, an oval mound, and a combination of two hills. Small perturbation theory was used, and the resulting Laplace equation for the perturbation velocity potential was solved by using either a product solution or a Green's function. The three dimensional solution is of interest in calculating the pressure distribution around obstacles, the flow of pollutants carried by the wind, and the augmentation of wind velocity for windmill siting. The augmentation in velocity at the top of a hill was found to be proportional to the hill height relative to a characteristic width dimension of the hill. An axisymmetric hill produced about 20 percent less velocity increase than a two dimensional ridge having the same cross-sectional profile.

  15. PLANS AND SECTIONS. WEIR SPILLWAY. TEXAS HILL CANAL STA. ...

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

    PLANS AND SECTIONS. WEIR SPILLWAY. TEXAS HILL CANAL - STA. 132+82.15. TEXAS HILL CANAL AND DISTRIBUTION SYSTEM. United States Department of Interior, Bureau of Reclamation; Gila Project, Arizona, Wellton-Mohawk Division. Drawing No. 50-D-3200, dated February 7, 1955, Denver, Colorado - Wellton-Mohawk Irrigation System, Relift Station, Texas Hill Canal 2.5, Northern Terminus of Avenue 51 East, approximately .5 mile south of Union Pacific Railroad, Wellton, Yuma County, AZ

  16. Correlates of simulated hill climb cycling performance.

    PubMed

    Davison, R C; Swan, D; Coleman, D; Bird, S

    2000-02-01

    The aim of this study was to assess the relationship between several commonly used aerobic and anaerobic cycle ergometer tests and performance during a treadmill cycling hill climb. Eight competitive cyclists (age 27+/-7 years; body mass 73.2+/-5.2 kg; height 177+/-6 cm; mean +/- s) completed six tests in random order: a lactate minimum test; a Wingate anaerobic power test; and two 6-km climbs at 6% and two 1-km climbs at 12% gradient performed on a motorized treadmill. The mean times and power outputs for the 6-km and 1-km climbs were 16:30+/-1:08 min: s and 330+/-17.8 W, and 4:19+/-0:27 min: s and 411+/-24.4 W, respectively. The best individual predictor of 6-km and 1-km performance times was the time for the corresponding climb at the other distance (r = 0.97). The next strongest predictor of both hill climb performances was the average power produced during the Wingate test divided by body mass. Stepwise regression analysis showed that the two variables contributing most to the prediction equation for both climbs were the Wingate average power per unit of body mass and maximal aerobic power divided by total mass (rider + bike), which together accounted for 92 and 96% of the variability in the 6-km and 1-km climbs. In conclusion, among competitive cyclists, the Wingate average power per unit of body mass was the best single predictor of simulated cycling hill climb performance at the distance and gradient used.

  17. Disappearing Ice

    NASA Technical Reports Server (NTRS)

    2008-01-01

    These images were acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on the 21st and 25th days of the mission, or Sols 20 and 24 (June 15 and 18, 2008).

    These images show sublimation of ice in the trench informally called 'Dodo-Goldilocks' over the course of four days.

    In the lower left corner, lumps disappear, similar to the process of evaporation.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  18. Mutations in MCT8 in patients with Allan-Herndon-Dudley-syndrome affecting its cellular distribution.

    PubMed

    Kersseboom, Simone; Kremers, Gert-Jan; Friesema, Edith C H; Visser, W Edward; Klootwijk, Wim; Peeters, Robin P; Visser, Theo J

    2013-05-01

    Monocarboxylate transporter 8 (MCT8) is a thyroid hormone (TH)-specific transporter. Mutations in the MCT8 gene are associated with Allan-Herndon-Dudley Syndrome (AHDS), consisting of severe psychomotor retardation and disturbed TH parameters. To study the functional consequences of different MCT8 mutations in detail, we combined functional analysis in different cell types with live-cell imaging of the cellular distribution of seven mutations that we identified in patients with AHDS. We used two cell models to study the mutations in vitro: 1) transiently transfected COS1 and JEG3 cells, and 2) stably transfected Flp-in 293 cells expressing a MCT8-cyan fluorescent protein construct. All seven mutants were expressed at the protein level and showed a defect in T3 and T4 transport in uptake and metabolism studies. Three mutants (G282C, P537L, and G558D) had residual uptake activity in Flp-in 293 and COS1 cells, but not in JEG3 cells. Four mutants (G221R, P321L, D453V, P537L) were expressed at the plasma membrane. The mobility in the plasma membrane of P537L was similar to WT, but the mobility of P321L was altered. The other mutants studied (insV236, G282C, G558D) were predominantly localized in the endoplasmic reticulum. In essence, loss of function by MCT8 mutations can be divided in two groups: mutations that result in partial or complete loss of transport activity (G221R, P321L, D453V, P537L) and mutations that mainly disturb protein expression and trafficking (insV236, G282C, G558D). The cell type-dependent results suggest that MCT8 mutations in AHDS patients may have tissue-specific effects on TH transport probably caused by tissue-specific expression of yet unknown MCT8-interacting proteins.

  19. New type of hill-top inflation

    NASA Astrophysics Data System (ADS)

    Barvinsky, A. O.; Kamenshchik, A. Yu.; Nesterov, D. V.

    2016-01-01

    We suggest a new type of hill-top inflation originating from the initial conditions in the form of the microcanonical density matrix for the cosmological model with a large number of quantum fields conformally coupled to gravity. Initial conditions for inflation are set up by cosmological instantons describing underbarrier oscillations in the vicinity of the inflaton potential maximum. These periodic oscillations of the inflaton field and cosmological scale factor are obtained within the approximation of two coupled oscillators subject to the slow roll regime in the Euclidean time. This regime is characterized by rapid oscillations of the scale factor on the background of a slowly varying inflaton, which guarantees smallness of slow roll parameters epsilon and η of the following inflation stage. A hill-like shape of the inflaton potential is shown to be generated by logarithmic loop corrections to the tree-level asymptotically shift-invariant potential in the non-minimal Higgs inflation model and R2-gravity. The solution to the problem of hierarchy between the Planckian scale and the inflation scale is discussed within the concept of conformal higher spin fields, which also suggests the mechanism bringing the model below the gravitational cutoff and, thus, protecting it from large graviton loop corrections.

  20. The Goodwin model: behind the Hill function.

    PubMed

    Gonze, Didier; Abou-Jaoudé, Wassim

    2013-01-01

    The Goodwin model is a 3-variable model demonstrating the emergence of oscillations in a delayed negative feedback-based system at the molecular level. This prototypical model and its variants have been commonly used to model circadian and other genetic oscillators in biology. The only source of non-linearity in this model is a Hill function, characterizing the repression process. It was mathematically shown that to obtain limit-cycle oscillations, the Hill coefficient must be larger than 8, a value often considered unrealistic. It is indeed difficult to explain such a high coefficient with simple cooperative dynamics. We present here molecular models of the standard Goodwin model, based on single or multisite phosphorylation/dephosphorylation processes of a transcription factor, which have been previously shown to generate switch-like responses. We show that when the phosphorylation/dephosphorylation processes are fast enough, the limit-cycle obtained with a multisite phosphorylation-based mechanism is in very good quantitative agreement with the oscillations observed in the Goodwin model. Conditions in which the detailed mechanism is well approximated by the Goodwin model are given. A variant of the Goodwin model which displays sharp thresholds and relaxation oscillations is also explained by a double phosphorylation/dephosphorylation-based mechanism through a bistable behavior. These results not only provide rational support for the Goodwin model but also highlight the crucial role of the speed of post-translational processes, whose response curve are usually established at a steady state, in biochemical oscillators.

  1. Spirit's Express Route to 'Columbia Hills'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This map illustrates the Mars Exploration Rover Spirit's position as of sol 112 (April 26, 2004), near the crater called 'Missoula.' Like a train on a tight schedule, Spirit will make regular stops along the way to its ultimate destination, the 'Columbia Hills.' At each stop, or 'station,' the rover will briefly analyze the area's rocks and soils. Each tick mark on the rover's route represents one sol's worth of travel, or about 60 to 70 meters (200 to 230 feet). Rover planners estimate that Spirit will reach the hills around mid-June. Presently, the rover is stopped at a site called 'Plains Station.'

    The color thermal data show how well different surface features hold onto heat. Red indicates warmth; blue indicates coolness. Areas with higher temperatures are more likely to be rocky, as rocks absorb heat. Lower temperatures denote small particles and fewer rocks. During its traverse, Spirit will document the causes of these temperature variations.

    The map comprises data from the camera on NASA's Mars Global Surveyor orbiter and the thermal emission imaging system on NASA's Mars Odyssey orbiter.

  2. Spirit's Express Route to 'Columbia Hills'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This map illustrates the Mars Exploration Rover Spirit's position as of sol 112 (April 26, 2004), near the crater called 'Missoula.' Like a train on a tight schedule, Spirit will make regular stops along the way to its ultimate destination, the 'Columbia Hills.' At each stop, or 'station,' the rover will briefly analyze the area's rocks and soils. Each tick mark on the rover's route represents one sol's worth of travel, or about 60 to 70 meters (200 to 230 feet). Rover planners estimate that Spirit will reach the hills around mid-June. Presently, the rover is stopped at a site called 'Plains Station.'

    The color thermal data show how well different surface features hold onto heat. Red indicates a higher thermal inertia associated with rocky terrain (cooler in the day, warmer at night); blue indicates a lower thermal inertia associated with smaller particles and fewer rocks (warmer at night, cooler in the day). During its traverse, Spirit will document the causes of these thermal variations.

    The map comprises data from the camera on NASA's Mars Global Surveyor orbiter and the thermal emission imaging system on NASA's Mars Odyssey orbiter.

  3. New type of hill-top inflation

    SciTech Connect

    Barvinsky, A.O.; Kamenshchik, A.Yu.; Nesterov, D.V.

    2016-01-20

    We suggest a new type of hill-top inflation originating from the initial conditions in the form of the microcanonical density matrix for the cosmological model with a large number of quantum fields conformally coupled to gravity. Initial conditions for inflation are set up by cosmological instantons describing underbarrier oscillations in the vicinity of the inflaton potential maximum. These periodic oscillations of the inflaton field and cosmological scale factor are obtained within the approximation of two coupled oscillators subject to the slow roll regime in the Euclidean time. This regime is characterized by rapid oscillations of the scale factor on the background of a slowly varying inflaton, which guarantees smallness of slow roll parameters ϵ and η of the following inflation stage. A hill-like shape of the inflaton potential is shown to be generated by logarithmic loop corrections to the tree-level asymptotically shift-invariant potential in the non-minimal Higgs inflation model and R{sup 2}-gravity. The solution to the problem of hierarchy between the Planckian scale and the inflation scale is discussed within the concept of conformal higher spin fields, which also suggests the mechanism bringing the model below the gravitational cutoff and, thus, protecting it from large graviton loop corrections.

  4. New type of hill-top inflation

    SciTech Connect

    Barvinsky, A.O.; Nesterov, D.V.; Kamenshchik, A.Yu. E-mail: Alexander.Kamenshchik@bo.infn.it

    2016-01-01

    We suggest a new type of hill-top inflation originating from the initial conditions in the form of the microcanonical density matrix for the cosmological model with a large number of quantum fields conformally coupled to gravity. Initial conditions for inflation are set up by cosmological instantons describing underbarrier oscillations in the vicinity of the inflaton potential maximum. These periodic oscillations of the inflaton field and cosmological scale factor are obtained within the approximation of two coupled oscillators subject to the slow roll regime in the Euclidean time. This regime is characterized by rapid oscillations of the scale factor on the background of a slowly varying inflaton, which guarantees smallness of slow roll parameters ε and η of the following inflation stage. A hill-like shape of the inflaton potential is shown to be generated by logarithmic loop corrections to the tree-level asymptotically shift-invariant potential in the non-minimal Higgs inflation model and R{sup 2}-gravity. The solution to the problem of hierarchy between the Planckian scale and the inflation scale is discussed within the concept of conformal higher spin fields, which also suggests the mechanism bringing the model below the gravitational cutoff and, thus, protecting it from large graviton loop corrections.

  5. Spirit on 'Husband Hill,' with 2004 Comparison

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Two Earth years ago, NASA's Mars Exploration Rover Spirit touched down in Gusev Crater. The rover marked its first Mars-year (687 Earth days) anniversary in November 2005. On Nov. 2, 2005, shortly before Spirit's Martian anniversary, the Mars Orbiter Camera on NASA's Mars Global Surveyor acquired an image centered on the rover's location in the 'Columbia Hills.' The location of Spirit on that date is circled on the image on the right. On the left, for comparison, is an image from Jan. 10, 2004, when few dreamed that the Spirit would ever reach the hills from its landing site about three kilometers (two miles) away.

    The newer image has a resolution of about 50 centimeters (1.6 feet) per pixel. North is up; illumination is from the left. The location is near 14.8 degrees south latitude, 184.6 degrees west longitude. Dr. Timothy J. Parker of the Mars Exploration Rover team at NASA's Jet Propulsion Laboratory, Pasadena, Calif., confirmed the location of the rover in the 2005 image. The scale bar is 50 meters (164 feet).

  6. Spirit's Neighborhood in 'Columbia Hills,' in Stereo

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Two Earth years ago, NASA's Mars Exploration Rover Spirit touched down in Gusev Crater. The rover marked its first Mars-year (687 Earth days) anniversary in November 2005. On Nov. 2, 2005, shortly before Spirit's Martian anniversary, the Mars Orbiter Camera on NASA's Mars Global Surveyor acquired an image covering approximately 3 kilometers by 3 kilometers (1.9 miles by 1.9 miles) centered on the rover's location in the 'Columbia Hills.'

    The tinted portion of this image gives a stereo, three-dimensional view when observed through 3-D glasses with a red left eye and blue right eye. The tallest peak is 'Husband Hill,' which was climbed by Spirit during much of 2005. The region south (toward the bottom) of these images shows the area where the rover is currently headed. The large dark patch and other similar dark patches in these images are accumulations of windblown sand and granules. North is up; illumination is from the left. The location is near 14.8 degrees south latitude, 184.6 degrees west longitude.

  7. The periodogram and Allan variance reveal fractal exponents greater than unity in auditory-nerve spike trains.

    PubMed

    Lowen, S B; Teich, M C

    1996-06-01

    Auditory-nerve spike trains exhibit fractal behavior, and therefore traditional renewal-point-process models fail to describe them adequately. Previous measures of the fractal exponent of these spike trains are based on the Fano factor and consequently cannot exceed unity. Two estimates of the fractal exponent are considered which do not suffer from this limit: one derived from the Allan variance, which was developed by the authors, and one based on the periodogram. These measures indicate that fractal exponents do indeed exceed unity for some nerve-spike recordings from stimulated primary afferent cat auditory-nerve fibers.

  8. Scrambled Ice

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This complex area on the side of Europa which faces away from Jupiter shows several types of features which are formed by disruptions of Europa's icy crust. North is to the top of the image, taken by NASA's Galileo spacecraft, and the Sun illuminates the surface from the left. The prominent wide, dark bands are up to 20 kilometers (12 miles) wide and over 50 kilometers (30 miles) long. They are believed to have formed when Europa's icy crust fractured, separated and filled in with darker, 'dirtier' ice or slush from below. A relatively rare type of feature on Europa is the 15-kilometer-diameter (9.3-mile) impact crater in the lower left corner. The small number of impact craters on Europa's surface is an indication of its relatively young age. A region of chaotic terrain south of this impact crater contains crustal plates which have broken apart and rafted into new positions. Some of these 'ice rafts' are nearly 1 kilometer (about half a mile) across. Other regions of chaotic terrain are visible and indicate heating and disruption of Europa's icy crust from below. The youngest features in this scene are the long, narrow cracks in the ice which cut across all other features. One of these cracks is about 30 kilometers (18 miles) to the right of the impact crater and extends for hundreds of miles from the top to the bottom of the image.

    The image, centered near 23 degrees south latitude and 179 degrees longitude, covers an area about 240 by 215 kilometers (150 by 130 miles) across. The finest details that can be discerned in this picture are about 460 meters (500 yards) across. The image was taken as Galileo flew by Europa on March 29, 1998. The image was taken by the onboard solid state imaging system camera from an altitude of 23,000 kilometers (14,000 miles).

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech

  9. 83. GENERAL VIEW FROM NORTH END OF GUN HILL PLATFORM ...

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

    83. GENERAL VIEW FROM NORTH END OF GUN HILL PLATFORM OF 3RD AVENUE EL SHOWING THE SOUTHBOUND TRACK APPROACH INTO GUN HILL STATION. 7TH AVENUE EXPRESS EL ABOVE. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY

  10. Abyssal hills: Influence of topography on benthic foraminiferal assemblages

    NASA Astrophysics Data System (ADS)

    Stefanoudis, Paris V.; Bett, Brian J.; Gooday, Andrew J.

    2016-11-01

    Abyssal plains, often thought of as vast flat areas, encompass a variety of terrains including abyssal hills, features that constitute the single largest landscape type on Earth. The potential influence on deep-sea benthic faunas of mesoscale habitat complexity arising from the presence of abyssal hills is still poorly understood. To address this issue we focus on benthic foraminifera (testate protists) in the >150-μm fraction of Megacorer samples (0-1 cm layer) collected at five different sites in the area of the Porcupine Abyssal Plain Sustained Observatory (NE Atlantic, 4850 m water depth). Three sites are located on the tops of small abyssal hills (200-500 m elevation) and two on the adjacent abyssal plain. We examined benthic foraminiferal assemblage characteristics (standing stock, diversity, composition) in relation to seafloor topography (hills vs. plain). Density and rarefied diversity were not significantly different between the hills and the plain. Nevertheless, hills do support a higher species density (i.e. species per unit area), a distinct fauna, and act to increase the regional species pool. Topographically enhanced bottom-water flows that influence food availability and sediment type are suggested as the most likely mechanisms responsible for these differences. Our findings highlight the potential importance of mesoscale heterogeneity introduced by relatively modest topography in regulating abyssal foraminiferal diversity. Given the predominance of abyssal hill terrain in the global ocean, we suggest the need to include faunal data from abyssal hills in assessments of abyssal ecology.

  11. Accounting for imperfect detection in Hill numbers for biodiversity studies

    USGS Publications Warehouse

    Broms, Kristin M.; Hooten, Mevin B.; Fitzpatrick, Ryan M.

    2015-01-01

    The occupancy-based Hill number estimators are always at their asymptotic values (i.e. as if an infinite number of samples have been taken for the study region), therefore making it easy to compare biodiversity between different assemblages. In addition, the Hill numbers are computed as derived quantities within a Bayesian hierarchical model, allowing for straightforward inference.

  12. "This Delightfull Garden": "Rabbit Hill" and the Pastoral Tradition.

    ERIC Educational Resources Information Center

    Jordan, Anne Devereaux

    1997-01-01

    Contends that Robert Lawson's children's book "Rabbit Hill" (1944) falls within the genre of pastoral literature, in the tradition of Edmund Spenser's "Faerie Queen." Examines the history of the genre and finds reasons for classifying Lawson's book as pastoral. Cites classic elements in "Rabbit Hill." Gives five…

  13. View of sports field and Easter Hill at west side ...

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

    View of sports field and Easter Hill at west side of project site. Looking southwest - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  14. View of sports field from Easter Hill looking at intersection ...

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

    View of sports field from Easter Hill looking at intersection of South Twenty-Sixth Street and Foothill Avenue at left center rear. Buildings No. 36, 35, 25, 27, and 29, from left to right. Looking northeast - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  15. View of sports field and Easter Hill at west side ...

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

    View of sports field and Easter Hill at west side of project site. Looking west - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  16. VIEW TO SOUTHEAST TOWARD QUARTERMASTER BUILDINGS GROUP AND RESERVOIR HILL, ...

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

    VIEW TO SOUTHEAST TOWARD QUARTERMASTER BUILDINGS GROUP AND RESERVOIR HILL, FROM AMMUNITION (IGLOO) HILL. (Part 2 of a 3 view panorama; see also CA-2398-J-1 and CA-2398-16.) - Hamilton Field, East of Nave Drive, Novato, Marin County, CA

  17. 1. BUNKER HILL LEAD SMELTER. VIEW IS FROM CENTRAL IMPOUNDMENT ...

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

    1. BUNKER HILL LEAD SMELTER. VIEW IS FROM CENTRAL IMPOUNDMENT AREA LOOKING SOUTH. PLANT DRY IS IN CENTER FOREGROUND, SLAG FUMING PLANT IS IN RIGHT FOREGROUND, AND BAG HOUSE IS IN RIGHT BACKGROUND. VARIOUS PLANT STACKS ARE ALSO VISIBLE. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  18. Spectral parameter power series representation for Hill's discriminant

    SciTech Connect

    Khmelnytskaya, K.V.; Rosu, H.C.

    2010-11-15

    We establish a series representation of the Hill discriminant based on the spectral parameter power series (SPPS) recently introduced by Kravchenko. We also show the invariance of the Hill discriminant under a Darboux transformation and employing the Mathieu case the feasibility of this type of series for numerical calculations of the eigenspectrum.

  19. View of south boundary of Easter Hill project site for ...

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

    View of south boundary of Easter Hill project site for right of way for Hoffman Boulevard. Buildings No. 11 and 14 at right in trees. Looking west - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  20. VIEW LOOKING WEST TOWARD RESERVOIR HILL. THE SPRR HOTEL WAS ...

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

    VIEW LOOKING WEST TOWARD RESERVOIR HILL. THE SPRR HOTEL WAS LOCATED IN THE STRIPED AREA AT THE BOTTOM OF THE IMAGE, AND THE TRACK RAN BETWEEN THE HILL AND THE HOTEL. - Southern Pacific Railroad Water Settling Reservoir, Yuma Crossing, south bank of Colorado River at foot of Madison Avenue, Yuma, Yuma County, AZ

  1. 78 FR 21098 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-09

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Black Hills National Forest Advisory Board (Board) will... Committee Act of 1972 (5 U.S.C. App. II) (FACA); and the Forest and Rangeland Renewable Resources...

  2. Drawing entitled "Sketch of proposed site for Pine Hills Patrol ...

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

    Drawing entitled "Sketch of proposed site for Pine Hills Patrol Station, Cleveland National Forest, San Diego County, California. Surveyed by Norman McClean, U.S.F.S., January, 1934. - Pine Hills Station, Barracks, West Side of Boulder Creek Road at Engineers Road, Julian, San Diego County, CA

  3. 3. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO ...

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

    3. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO THE SOUTHWEST. BUILDINGS NOTED IN ID-29-2 APPEAR, IN ADDITION TO DRY ORE PLANT AND BONNOT COAL PULVERIZING EQUIPMENT BUILDING ON THE RIGHT. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  4. 2. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO ...

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

    2. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO THE SOUTH. IN FOREGROUND, PLANT DRY, SLAG FUMING PLANT, BLAST FURNACE, SMELTER OFFICE, LEAD AND SILVER REFINERIES ARE VISIBLE, L. TO R. HIGH VELOCITY FLUE LEADS FROM LOWER PLANT TO BAG HOUSE AND STACKS AT TOP OF SMELTING FACILITY. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  5. Axillary shoulder with exaggerated rotation: the Hill-Sachs defect.

    PubMed

    Rafert, J A; Long, B W; Hernandez, E M; Kreipke, D L

    1990-01-01

    One of the most common fractures of the humeral head resulting from an anterior dislocation is the Hill-Sachs defect. Other special radiographic positions to demonstrate this injury may prove difficult for the patient to assume and maintain. An axillary shoulder projection with exaggerated external rotation is easy to position and clearly demonstrates the Hill-Sachs defect.

  6. AmeriFlux US-Blk Black Hills

    DOE Data Explorer

    Meyers, Tilden [NOAA/ARL

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Blk Black Hills. Site Description - The Black Hills tower was established by the Institute for Atmospheric Studies of the South Dakota School of Mines and Technology.

  7. OVERVIEW OF GOLD HILL MILL, ROAD, AND WHITE PINE TALC ...

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

    OVERVIEW OF GOLD HILL MILL, ROAD, AND WHITE PINE TALC MINE LOOKING EAST. THE OPENING TO THE TALC MINE IS IN THE DARK AREA AT CENTER LEFT EDGE. WARM SPRINGS CAMP IS OUT OF FRAME TO THE RIGHT. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  8. Decay of isolated hills and saddles on Si(001)

    NASA Astrophysics Data System (ADS)

    Kirschbaum, Pierre; Brendel, Lothar; Roos, Kelly R.; Horn-von Hoegen, Michael; Heringdorf, Frank-J. Meyer zu

    2016-08-01

    We discuss the high temperature decay of isolated hills and saddle points on Si(001). Using in situ dark-field imaging in low energy electron microscopy, we track the movement of individual steps during high temperature annealing. We find different temperature dependent decay rates for the top of the hill compared to a saddle point with low step density that is present in the vicinity of the hill. The decay rate of the hill is always higher than the decay rate at the saddle. The two rates converge with increasing temperature and become equal at temperatures above 1060 °C. We also report an alternating fast and low decay rate for the layer-by-layer decay of the hills. This surprising finding is independent of temperature and is explained by macroscopic strain in the sample.

  9. Comparisons of calculated and measured helicopter noise near instrument hill

    NASA Technical Reports Server (NTRS)

    Bass, Henry E.; You, Chulsoo

    1993-01-01

    The polar parabolic equation (POPE) method solves for the diffraction of sound by a curved surface including a realistic sound speed profile. POPE is outlined briefly to describe diffraction which propagates the field over a hill. Experimental data are compared with POPE predictions using the measured sound speed profile and ground impedance. Two trial cases are considered for the comparisons: the helicopter located at the base of the hill and far away from the base of the hill, respectively. The physical mechanisms for sound propagation over a hill are examined with and of POPE calculations and experimental data. The shedding of rays from the hillside gives an interference effect with a wave along the flat surface beyond the base of a hill.

  10. Modern Airfoil Ice Accretions

    NASA Technical Reports Server (NTRS)

    Addy, Harold E., Jr.; Potapczuk, Mark G.; Sheldon, David W.

    1997-01-01

    This report presents results from the first icing tests performed in the Modem Airfoils program. Two airfoils have been subjected to icing tests in the NASA Lewis Icing Research Tunnel (IRT). Both airfoils were two dimensional airfoils; one was representative of a commercial transport airfoil while the other was representative of a business jet airfoil. The icing test conditions were selected from the FAR Appendix C envelopes. Effects on aerodynamic performance are presented including the effects of varying amounts of glaze ice as well as the effects of approximately the same amounts of glaze, mixed, and rime ice. Actual ice shapes obtained in these tests are also presented for these cases. In addition, comparisons are shown between ice shapes from the tests and ice shapes predicted by the computer code, LEWICE for similar conditions. Significant results from the tests are that relatively small amounts of ice can have nearly as much effect on airfoil lift coefficient as much greater amounts of ice and that glaze ice usually has a more detrimental effect than either rime or mixed ice. LEWICE predictions of ice shapes, in general, compared reasonably well with ice shapes obtained in the IRT, although differences in details of the ice shapes were observed.

  11. Antarctic lakes (above and beneath the ice sheet): Analogues for Mars

    NASA Technical Reports Server (NTRS)

    Rice, J. W., Jr.

    1992-01-01

    The perennial ice covered lakes of the Antarctic are considered to be excellent analogues to lakes that once existed on Mars. Field studies of ice covered lakes, paleolakes, and polar beaches were conducted in the Bunger Hills Oasis, Eastern Antarctica. These studies are extended to the Dry Valleys, Western Antarctica, and the Arctic. Important distinctions were made between ice covered and non-ice covered bodies of water in terms of the geomorphic signatures produced. The most notable landforms produced by ice covered lakes are ice shoved ridges. These features form discrete segmented ramparts of boulders and sediments pushed up along the shores of lakes and/or seas. Sub-ice lakes have been discovered under the Antarctic ice sheet using radio echo sounding. These lakes occur in regions of low surface slope, low surface accumulations, and low ice velocity, and occupy bedrock hollows. The presence of sub-ice lakes below the Martian polar caps is possible. The discovery of the Antarctic sub-ice lakes raises possibilities concerning Martian lakes and exobiology.

  12. Operational teledermatology in Broken Hill, rural Australia.

    PubMed

    See, Adrian; Lim, Adrian C; Le, Katie; See, Jo-Ann; Shumack, Stephen P

    2005-08-01

    From January 2001 to January 2002, Broken Hill, New South Wales, served as a trial site for teledermatology as one method of access to dermatologists. Fourteen participating general practitioners referred 46 patients making up 48 teledermatology cases. The mean diagnostic agreement between general practitioners and dermatologists was 35% and 50% for primary and differential diagnoses, respectively. Teledermatology patients formed 12% of the collectively referred dermatology patients (outpatients and teledermatology). In this project, high patient and general practitioner acceptability and positive medical outcomes confirm the value of rural teledermatology. However, this project also revealed unexpected barriers and pitfalls in the effective operation of rural teledermatology. Lack of education of participants, inertia among potential users and patient inconvenience are issues that may adversely affect the effective implementation of rural teledermatology.

  13. Seeing sodomy: Fanny Hill's blinding vision.

    PubMed

    Kopelson, K

    1992-01-01

    One of the oddest and most erotic moments in Cleland's Fanny Hill occurs when Fanny is knocked "senseless" by a voyeuristic vision of two young men having anal intercourse. This sodomitical passage demonstrates a dominant culture's strong phobic attraction to a socially peripheral Other against which it defines itself. The passage also represents two types of transgression. On one level, it records an inversion of sex, gender, and class paradigms that structure bourgeois subjectivity. On another level, the passage also transgresses signification itself, exploding as well as inverting those paradigms, in a movement that recalls Barthes's distinction between the coded "studium" of the pornographic and the uncoded "punctum" of the erotic. This transgressive exemption from meaning might well be read, in a Barthesian sense, as true sexual enfranchisement in that, for Barthes, the liberation of sexuality requires the release of sexuality from meaning, and from transgression as meaning.

  14. The 1984 Morgan Hill, California, earthquake

    USGS Publications Warehouse

    Bakun, W.H.; Clark, M.M.; Cockerham, R.S.; Ellsworth, W.L.; Lindh, A.G.; Prescott, W.H.; Shakal, A.F.; Spudich, P.

    1984-01-01

    The Morgan Hill, California, earthquake (magnitude 6.1) of 24 April 1984 ruptured a 30-kilometer-long segment of the Calaveras fault zone to the east of San Jose. Although it was recognized in 1980 that an earthquake of magnitude 6 occurred on this segment in 1911 and that a repeat of this event might reasonably be expected, no short-term precursors were noted and so the time of the 1984 earthquake was not predicted. Unilateral rupture propagation toward the south-southeast and an energetic late source of seismic radiation located near the southeast end of the rupture zone contributed to the highly focused pattern of strong motion, including an exceptionally large horizontal acceleration of 1.29g at a site on a dam abutment near the southeast end of the rupture zone.

  15. Motivations of female Black Hills deer hunters

    USGS Publications Warehouse

    Gigliotti, Larry M.; Covelli Metcalf, Elizabeth

    2016-01-01

    State fish and wildlife agencies are particularly interested in attracting female participation because of the potential to offset declining participation in hunting. Understanding female hunters’ motivations will be critical for designing effective recruitment and retention programs for women hunters. Although female participation in hunting is increasing, males still outnumber females by about tenfold. Gender differences in deer hunters were explored by comparing ratings of eight motivations (social, nature, excitement, meat, challenge, trophy, extra hunting opportunity, and solitude). Hunter types were defined by hunters’ selection of the most important motivation for why they like Black Hills deer hunting. Overall, females and males were relatively similar in their ratings of the eight motivations, and we found 85% gender similarity in the selection of the most important motivation. Women were slightly more motivated by the food aspect of the hunt while men placed slightly more value on the hunt as a sporting activity.

  16. AGU climate scientists visit Capitol Hill

    NASA Astrophysics Data System (ADS)

    Hankin, Erik

    2012-02-01

    On 1 February 2012, AGU teamed with 11 other scientific societies to bring 29 scientists researching various aspects of climate change to Washington, D. C., for the second annual Climate Science Day on Capitol Hill. The participants represented a wide range of expertise, from meteorology to agriculture, paleoclimatology to statistics, but all spoke to the reality of climate change as demonstrated in their scientific research. With Congress debating environmental regulations and energy policy amid tight fiscal pressures, it is critical that lawmakers have access to the best climate science to help guide policy decisions. The scientists met with legislators and their staff to discuss the importance of climate science for their districts and the nation and offered their expertise as an ongoing resource to the legislators.

  17. After Conquering 'Husband Hill,' Spirit Moves On

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The first explorer ever to scale a summit on another planet, NASA's Mars Exploration Rover Spirit has begun a long trek downward from the top of 'Husband Hill' to new destinations. As shown in this 180-degree panorama from east of the summit, Spirit's earlier tracks are no longer visible. They are off to the west (to the left in this view). Spirit's next destination is 'Haskin Ridge,' straight ahead along the edge of the steep cliff on the right side of this panorama.

    The scene is a mosaic of images that Spirit took with the navigation camera on the rover's 635th Martian day, or sol, (Oct. 16, 2005) of exploration of Gusev Crater on Mars. This view is presented in a cylindrical projection with geometric seam correction.

  18. Icing: Accretion, Detection, Protection

    NASA Technical Reports Server (NTRS)

    Reinmann, John J.

    1994-01-01

    The global aircraft industry and its regulatory agencies are currently involved in three major icing efforts: ground icing; advanced technologies for in-flight icing; and tailplane icing. These three major icing topics correspondingly support the three major segments of any aircraft flight profile: takeoff; cruise and hold; and approach and land. This lecture addressess these three topics in the same sequence as they appear in flight, starting with ground deicing, followed by advanced technologies for in-flight ice protection, and ending with tailplane icing.

  19. Ash and Steam, Soufriere Hills Volcano, Monserrat

    NASA Technical Reports Server (NTRS)

    2002-01-01

    International Space Station crew members are regularly alerted to dynamic events on the Earth's surface. On request from scientists on the ground, the ISS crew observed and recorded activity from the summit of Soufriere Hills on March 20, 2002. These two images provide a context view of the island (bottom) and a detailed view of the summit plume (top). When the images were taken, the eastern side of the summit region experienced continued lava growth, and reports posted on the Smithsonian Institution's Weekly Volcanic Activity Report indicate that 'large (50-70 m high), fast-growing, spines developed on the dome's summit. These spines periodically collapsed, producing pyroclastic flows down the volcano's east flank that sometimes reached the Tar River fan. Small ash clouds produced from these events reached roughly 1 km above the volcano and drifted westward over Plymouth and Richmond Hill. Ash predominately fell into the sea. Sulfur dioxide emission rates remained high. Theodolite measurements of the dome taken on March 20 yielded a dome height of 1,039 m.' Other photographs by astronauts of Montserrat have been posted on the Earth Observatory: digital photograph number ISS002-E-9309, taken on July 9, 2001; and a recolored and reprojected version of the same image. Digital photograph numbers ISS004-E-8972 and 8973 were taken 20 March, 2002 from Space Station Alpha and were provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  20. A preliminary comparison of two perennially ice-covered lakes in Antarctica: analogs of past Martian lacustrine environments.

    PubMed

    Andersen, D T; Doran, P; Bolshiyanov, D; Rice, J; Galchenko, V; Cherych, N; Wharton, R A; McKay, C P; Meyer, M; Garshnek, V

    1995-03-01

    Perennially ice-covered lakes in the Antarctic have been suggested as analogs to lakes which may have existed on the surface of Mars 3.5 billion years ago. During the 1991-1992 austral summer, a joint Russian/American research effort was directed at studies of ice-covered lakes in the Bunger Hills Oasis, Antarctica (66 degrees S, 100 degrees E). The primary objective of the expedition was to investigate this ice-free area for features analogous to ancient martian environments that may have been capable of supporting life and to compare the ice-covered lakes of the Bunger Hills with those in the McMurdo Dry Valleys of southern Victoria Land (77 degrees S, 166 degrees E) as part of the continuing studies of Antarctic-Mars analogs.

  1. Magnetotelluric investigation of the Vestfold Hills and Rauer Group, East Antarctica

    NASA Astrophysics Data System (ADS)

    Peacock, J. R.; Selway, K.

    2016-04-01

    The Vestfold Hills and Rauer Group in East Antarctica have contrasting Archean to Neoproterozoic geological histories and are believed to be juxtaposed along a suture zone that now lies beneath the Sørsdal Glacier. Exact location and age of this suture zone are unknown, as is its relationship to regional deformation associated with the amalgamation of East Gondwana. To image the suture zone, magnetotelluric (MT) data were collected in Prydz Bay, East Antarctica, mainly along a profile crossing the Sørsdal Glacier and regions inland of the Vestfold Hills and Rauer Group islands. Time-frequency analysis of the MT time series yielded three important observations: (1) Wind speeds in excess of ˜8 m/s reduce coherence between electric and magnetic fields due to charged wind-blown particles of ice and snow. (2) Estimation of the MT transfer function is best between 1000 and 1400 UT when ionospheric Hall currents enhance the magnetic source field. (3) Nonplanar source field effects were minimal but detectable and removed from estimation of the MT transfer function. Inversions of MT data in 2-D and 3-D produce similar resistivity models, where structures in the preferred 3-D resistivity model correlate strongly with regional magnetic data. The electrically conductive Rauer Group is separated from the less conductive Vestfold Hills by a resistive zone under the Sørsdal Glacier, which is interpreted to be caused by oxidation during suturing. Though a suture zone has been imaged, no time constrains on suturing can be made from the MT data.

  2. Magnetotelluric investigation of the Vestfold Hills and Rauer Group, East Antarctica

    USGS Publications Warehouse

    Peacock, Jared R.; Selway, Katherine

    2016-01-01

    The Vestfold Hills and Rauer Group in East Antarctica have contrasting Archean to Neoproterozoic geological histories and are believed to be juxtaposed along a suture zone that now lies beneath the Sørsdal Glacier. Exact location and age of this suture zone are unknown, as is its relationship to regional deformation associated with the amalgamation of East Gondwana. To image the suture zone, magnetotelluric (MT) data were collected in Prydz Bay, East Antarctica, mainly along a profile crossing the Sørsdal Glacier and regions inland of the Vestfold Hills and Rauer Group islands. Time-frequency analysis of the MT time series yielded three important observations: (1) Wind speeds in excess of ∼8 m/s reduce coherence between electric and magnetic fields due to charged wind-blown particles of ice and snow. (2) Estimation of the MT transfer function is best between 1000 and 1400 UT when ionospheric Hall currents enhance the magnetic source field. (3) Nonplanar source field effects were minimal but detectable and removed from estimation of the MT transfer function. Inversions of MT data in 2-D and 3-D produce similar resistivity models, where structures in the preferred 3-D resistivity model correlate strongly with regional magnetic data. The electrically conductive Rauer Group is separated from the less conductive Vestfold Hills by a resistive zone under the Sørsdal Glacier, which is interpreted to be caused by oxidation during suturing. Though a suture zone has been imaged, no time constrains on suturing can be made from the MT data.

  3. High-resolution continuous-flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

    2015-07-01

    Here we present an experimental setup for water stable isotope (δ18O and δD) continuous-flow measurements and provide metrics defining the performance of the setup during a major ice core measurement campaign (Roosevelt Island Climate Evolution; RICE). We also use the metrics to compare alternate systems. Our setup is the first continuous-flow laser spectroscopy system that is using off-axis integrated cavity output spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research, LGR) in combination with an evaporation unit to continuously analyze water samples from an ice core. A Water Vapor Isotope Standard Source (WVISS) calibration unit, manufactured by LGR, was modified to (1) enable measurements on several water standards, (2) increase the temporal resolution by reducing the response time and (3) reduce the influence from memory effects. While this setup was designed for the continuous-flow analysis (CFA) of ice cores, it can also continuously analyze other liquid or vapor sources. The custom setups provide a shorter response time (~ 54 and 18 s for 2013 and 2014 setup, respectively) compared to the original WVISS unit (~ 62 s), which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the custom setups have a reduced memory effect. Stability tests comparing the custom and WVISS setups were performed and Allan deviations (σAllan) were calculated to determine precision at different averaging times. For the custom 2013 setup the precision after integration times of 103 s is 0.060 and 0.070 ‰ for δ18O and δD, respectively. The corresponding σAllan values for the custom 2014 setup are 0.030, 0.060 and 0.043 ‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042 ‰ after 103 s for δ18O, δD and δ17O, respectively. Both the custom setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan

  4. High-resolution continuous flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

    2014-12-01

    Here we present an experimental setup for water stable isotopes (δ18O and δD) continuous flow measurements. It is the first continuous flow laser spectroscopy system that is using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research - LGR) in combination with an evaporation unit to continuously analyze sample from an ice core. A Water Vapor Isotopic Standard Source (WVISS) calibration unit, manufactured by LGR, was modified to: (1) increase the temporal resolution by reducing the response time (2) enable measurements on several water standards, and (3) to reduce the influence from memory effects. While this setup was designed for the Continuous Flow Analysis (CFA) of ice cores, it can also continuously analyze other liquid or vapor sources. The modified setup provides a shorter response time (~54 and 18 s for 2013 and 2014 setup, respectively) compared to the original WVISS unit (~62 s), which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the modified setup has a reduced memory effect. Stability tests comparing the modified WVISS and WVISS setups were performed and Allan deviations (σAllan) were calculated to determine precision at different averaging times. For the 2013 modified setup the precision after integration times of 103 s are 0.060 and 0.070‰ for δ18O and δD, respectively. For the WVISS setup the corresponding σAllan values are 0.030, 0.060 and 0.043‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042‰ after 103 s for δ18O, δD and δ17O, respectively. Both the modified setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan values for δ18O of 0.30 and 0.18‰ for the modified (2013) and WVISS setup, respectively after averaging times of 104 s (2.78 h). The Isotopic Water Analyzer (IWA)-modified WVISS setup used during the

  5. Beacon Hill end moraine, Boston: new explanation of an important urban feature

    USGS Publications Warehouse

    Kaye, Clifford A.; Coates, Donald R.

    1976-01-01

    The usefulness of geology to engineers is in direct proportion to how well it helps us predict the subsurface; these predictions, in turn, depend on our knowledge of the geomorphic processes that molded the terrain. The uncertainties of interpretation are particularly great in glaciated terrain because our understanding of both glacial processes and history is so incomplete, a fact well illustrated in Beacon Hill. Recent construction activities in the eastern part of the hill, until now classified as a drumlin, have shown that it is better interpreted as an end moraine formed by a Wisconsonian glacial readvance. Instead of the firm till that was anticipated as foundation material, excavations exposed a complex of sand, gravel, and clay, with only minor zones of till. The structure of these deposits strongly suggests that originally they were plates of the glacial bed that froze to the glacier and were transported englacially. Thrust faulting and other deformations are glacial structures formed within the ice in the glacier's terminal zone. In spite of the complex englacial history, these deposits lost little of their original appearance and intergranular relationships. Upon deglaciation, the frozen moraine thawed, and slumping formed complex secondary structures on the ridge's lower flanks.

  6. Evaluation of Meterorite Amono Acid Analysis Data Using Multivariate Techniques

    NASA Technical Reports Server (NTRS)

    McDonald, G.; Storrie-Lombardi, M.; Nealson, K.

    1999-01-01

    The amino acid distributions in the Murchison carbonaceous chondrite, Mars meteorite ALH84001, and ice from the Allan Hills region of Antarctica are shown, using a multivariate technique known as Principal Component Analysis (PCA), to be statistically distinct from the average amino acid compostion of 101 terrestrial protein superfamilies.

  7. Ice Clouds

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Heavy water ice clouds almost completely obscure the surface in Vastitas Borealis.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

    Image information: VIS instrument. Latitude 69.5, Longitude 283.6 East (76.4 West). 19 meter/pixel resolution.

  8. Arctic ice islands

    SciTech Connect

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  9. Descent from the Summit of 'Husband Hill' (False Color)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    In late November 2005 while descending 'Husband Hill,' NASA's Mars Exploration Rover Spirit took the most detailed panorama so far of the 'Inner Basin,' the rover's next target destination. Spirit acquired the 405 individual images that make up this 360-degree view of the surrounding terrain using five different filters on the panoramic camera. The rover took the images on Martian days, or sols, 672 to 677 (Nov. 23 to 28, 2005 -- the Thanksgiving holiday weekend).

    This image is a false-color rendering using camera's 750-, 530-, and 430-nanometer filters, emphasizing some colors more than others to enhance striking but subtle color differences among rocks, soils, hills, and plains.

    'Home Plate,' a bright, semi-circular feature scientists hope to investigate, is harder to discern in this image than in earlier views taken from higher up the hill. Spirit acquired this more oblique view, known as the 'Seminole panorama,' from about halfway down the south flank of Husband Hill, 50 meters (164 feet) or so below the summit. Near the center of the panorama, on the horizon, are 'McCool Hill' and 'Ramon Hill,' named, like Husband Hill, in honor of the fallen astronauts of the space shuttle Columbia. Husband Hill is visible behind the rover, on the right and left sides of the panorama. An arc of rover tracks made while avoiding obstacles and getting into position to examine rock outcrops can be traced over a long distance by zooming in to explore the panorama in greater detail.

    Spirit is now significantly farther downhill toward the center of this panorama, en route to Home Plate and other enigmatic soils and outcrop rocks in the quest to uncover the history of Gusev Crater and the 'Columbia Hills.'

  10. Utilizing "The William Allan Kritsonis Balanced Teeter-Totter Model" as a Means to Cultivate a Legacy of Transformational Leaders in Schools: A National Focus

    ERIC Educational Resources Information Center

    Jacobs, Karen Dupre

    2007-01-01

    The Kritsonis Teeter-Totter Model, developed by Dr. William Allan Kritsonis, is utilized to cultivate a legacy of transformational leaders in schools throughout the United States. In a time when change in schools is inevitable, the model aides school leaders in better defining their individual role in schools and that of their stakeholders in…

  11. Sea ice ecosystems.

    PubMed

    Arrigo, Kevin R

    2014-01-01

    Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.

  12. Iced-airfoil aerodynamics

    NASA Astrophysics Data System (ADS)

    Bragg, M. B.; Broeren, A. P.; Blumenthal, L. A.

    2005-07-01

    Past research on airfoil aerodynamics in icing are reviewed. This review emphasizes the time period after the 1978 NASA Lewis workshop that initiated the modern icing research program at NASA and the current period after the 1994 ATR accident where aerodynamics research has been more aircraft safety focused. Research pre-1978 is also briefly reviewed. Following this review, our current knowledge of iced airfoil aerodynamics is presented from a flowfield-physics perspective. This article identifies four classes of ice accretions: roughness, horn ice, streamwise ice, and spanwise-ridge ice. For each class, the key flowfield features such as flowfield separation and reattachment are discussed and how these contribute to the known aerodynamic effects of these ice shapes. Finally Reynolds number and Mach number effects on iced-airfoil aerodynamics are summarized.

  13. Stochastic ice stream dynamics

    NASA Astrophysics Data System (ADS)

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-01

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution.

  14. Sea Ice Ecosystems

    NASA Astrophysics Data System (ADS)

    Arrigo, Kevin R.

    2014-01-01

    Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.

  15. Stochastic ice stream dynamics

    PubMed Central

    Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-01-01

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution. PMID:27457960

  16. Top Sounder Ice Penetration

    NASA Astrophysics Data System (ADS)

    Porter, D. L.; Goemmer, S. A.; Sweeney, J. H.

    2014-12-01

    Ice draft measurements are made as part of normal operations for all US Navy submarines operating in the Arctic Ocean. The submarine ice draft data are unique in providing high resolution measurements over long transects of the ice covered ocean. The data has been used to document a multidecadal drop in ice thickness, and for validating and improving numerical sea-ice models. A submarine upward-looking sonar draft measurement is made by a sonar transducer mounted in the sail or deck of the submarine. An acoustic beam is transmitted upward through the water column, reflecting off the bottom of the sea ice and returning to the transducer. Ice thickness is estimated as the difference between the ship's depth (measured by pressure) and the acoustic range to the bottom of the ice estimated from the travel time of the sonar pulse. Digital recording systems can provide the return off the water-ice interface as well as returns that have penetrated the ice. Typically, only the first return from the ice hull is analyzed. Information regarding ice flow interstitial layers provides ice age information and may possibly be derived with the entire return signal. The approach being investigated is similar to that used in measuring bottom sediment layers and will involve measuring the echo level from the first interface, solving the reflection loss from that transmission, and employing reflection loss versus impedance mismatch to ascertain ice structure information.

  17. Ross Ice Shelf, Antarctic Ice and Clouds

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In this view of Antarctic ice and clouds, (56.5S, 152.0W), the Ross Ice Shelf of Antarctica is almost totally clear, showing stress cracks in the ice surface caused by wind and tidal drift. Clouds on the eastern edge of the picture are associated with an Antarctic cyclone. Winds stirred up these storms have been known to reach hurricane force.

  18. Evolution of the Puente Hills Thrust Fault

    NASA Astrophysics Data System (ADS)

    Bergen, K. J.; Shaw, J. H.; Dolan, J. F.

    2013-12-01

    This study aims to assess the evolution of the blind Puente Hills thrust fault system (PHT) by determining its age of initiation, lateral propagation history, and changes in slip rate over time. The PHT presents one of the largest seismic hazards in the United States, given its location beneath downtown Los Angeles. The PHT is comprised of three fault segments: the Los Angeles (LA), Santa Fe Springs (SFS), and Coyote Hills (CH). The LA and SFS segments are characterized by growth stratigraphy where folds formed by uplift on the fault segments have been continually buried by sediment from the Los Angeles and San Gabriel rivers. The CH segment has developed topography and is characterized by onlapping growth stratigraphy. This depositional setting gives us the unique opportunity to measure uplift on the LA and SFS fault segments, and minimum uplift on the CH fault segment, as the difference in sediment thicknesses across the buried folds. We utilize depth converted oil industry seismic reflection data to image the fold geometries. Identifying time-correlative stratigraphic markers for slip rate determination in the basin has been a problem for researchers in the past, however, as the faunal assemblages observed in wells are time-transgressive by nature. To overcome this, we utilize the sequence stratigraphic model and well picks of Ponti et al. (2007) as a basis for mapping time-correlative sequence boundaries throughout our industry seismic reflection data from the present to the Pleistocene. From the Pleistocene to Miocene we identify additional sequence boundaries in our seismic reflection data from imaged sequence geometries and by correlating industry well formation tops. The sequence and formation top picks are then used to build 3-dimensional surfaces in the modeling program Gocad. From these surfaces we measure the change in thicknesses across the folds to obtain uplift rates between each sequence boundary. Our results show three distinct phases of

  19. 18. Historic American Buildings Survey Joseph Hill, Photographer May 26, ...

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

    18. Historic American Buildings Survey Joseph Hill, Photographer May 26, 1936 FIREPLACE IN DINING ROOM, The Davenport House, Rock Island Arsenal - Rock Island Arsenal, Building No. 346, Davenport Drive, Arsenal Grounds, Rock Island, Rock Island County, IL

  20. 258. Dennis Hill, Photographer April 1998 VIEW OF CANTILEVER TRUSS ...

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

    258. Dennis Hill, Photographer April 1998 VIEW OF CANTILEVER TRUSS ANCHOR ARM AT PIERS E- AND E-2, SOUTH SIDE, FACING NORTH. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  1. 81. VIEW NORTH ON WEST SIDE OF GUN HILL PLATFORM ...

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

    81. VIEW NORTH ON WEST SIDE OF GUN HILL PLATFORM SHOWING LAMP STANDARDS FOR NIGHT LIGHTNING. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY

  2. 28. VIEW OF BRIDGE, LOOKING WEST FROM CREST OF HILL ...

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

    28. VIEW OF BRIDGE, LOOKING WEST FROM CREST OF HILL ABOVE EAST TOWER. NOTE SWAY CABLES ON EACH SIDE OF THE WALKWAY. March 1987 - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  3. 184. Dennis Hill, Photographer June 1998 DETAIL VIEW OF UPPER ...

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

    184. Dennis Hill, Photographer June 1998 DETAIL VIEW OF UPPER DECK EXPANSION JOINT AT PIER W-2, FACING WEST-SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  4. 2. Historic American Buildings Survey Joseph Hill, Photographer May 10, ...

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

    2. Historic American Buildings Survey Joseph Hill, Photographer May 10, 1936 CAST IRON GATE AT 1352 W. Washington Blvd., Chicago - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  5. 1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 FENCE RAILING 1133 WEST WASHINGTON BLVD. - Chicago Ironwork, 1133 West Washington Boulevard (Cast Iron Fence & Railing), 1133 West Washington Boulevard, Chicago, Cook County, IL

  6. 1. Historic American Buildings Survey Joseph Hill, Photographer July, 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer July, 1936 PORCH RAILING, 1149 W. WASHINGTON Blvd. - Chicago Ironwork, 1149 West Washington Boulevard (Cast Iron Stair Railing), 1149 West Washington Boulevard, Chicago, Cook County, IL

  7. 6. Historic American Buildings Survey Joseph Hill, Photographer April 1, ...

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

    6. Historic American Buildings Survey Joseph Hill, Photographer April 1, 1936 MANTEL 1352 W. Washington Blvd., Chicago - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  8. Context view looking west from hill with tree in foreground. ...

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

    Context view looking west from hill with tree in foreground. Entist Mountains are in distance. - Badger Mountain Lookout, .125 mile northwest of Badger Mountain summit, East Wenatchee, Douglas County, WA

  9. 12. ARROYO SECO PARKWAY SEEN FROM RADIO TOWER HILL. NOTE ...

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

    12. ARROYO SECO PARKWAY SEEN FROM RADIO TOWER HILL. NOTE PARALLEL SURFACE STREET AT LEFT AND AVENUE 43 BRIDGE AT RIGHT. LOOKING 342° NNW. - Arroyo Seco Parkway, Los Angeles to Pasadena, Los Angeles, Los Angeles County, CA

  10. View looking east over coal tipple toward Friendship Hill, home ...

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

    View looking east over coal tipple toward Friendship Hill, home of Albert Gallatin, in right background behine bridge. - Monongahela Railroad, New Geneva Bridge, Spanning Monongahela River, South of Lock & Dam No. 7, New Geneva, Fayette County, PA

  11. 117. Dennis Hill, Photographer April 1998 VIEW UP ESSEX STREET ...

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

    117. Dennis Hill, Photographer April 1998 VIEW UP ESSEX STREET AT UPPER DECK OFF-RAMP, FACING NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  12. 132. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL ...

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

    132. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP FROM NATOMA STREET BETWEEN FIRST AND SECOND STREETS, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  13. 122. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK ...

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

    122. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK OFF-RAMP AND TRANSBAY TERMINAL BUS LOOP, SOUTHWEST OF FIRST STREET, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  14. 139. Dennis Hill, Photographer January 1998 ELEVATION VIEW OF TRANSBAY ...

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

    139. Dennis Hill, Photographer January 1998 ELEVATION VIEW OF TRANSBAY TERMINAL BUS LOOP CROSSING OVER HARRISON STREET, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  15. 127. Dennis Hill, Photographer April 1998 DETAIL VIEW OF TRANSBAY ...

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

    127. Dennis Hill, Photographer April 1998 DETAIL VIEW OF TRANSBAY TERMINAL BUS LOOP CROSSING OVER HOWARD STREET NORTHEAST OF BEALE STREET, FACING WEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  16. 124. Dennis Hill, Photographer April 1998 VIEW OF TRANSBAY TERMINAL ...

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

    124. Dennis Hill, Photographer April 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP CROSSING OVER FREMONT STREET, FACING NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  17. 137. Dennis Hill, Photographer April 1998 VIEW OF TRANSBAY TERMINAL ...

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

    137. Dennis Hill, Photographer April 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP AT SPLIT, FACING NORTH. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  18. 129. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL ...

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

    129. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP FROM HOWARD STREET NORTHEAST OF BEALE STREET, FACING NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  19. 136. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL ...

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

    136. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP AT SPLIT (FROM GROUND LEVEL), FACING SOUTH-SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  20. 135. Dennis Hill, Photographer December 1997 VIEW OF TRANSBAY TERMINAL ...

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

    135. Dennis Hill, Photographer December 1997 VIEW OF TRANSBAY TERMINAL BUS LOOP AT SPLIT, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  1. 134. Dennis Hill, Photographer April 1998 VIEW OF TRANSBAY TERMINAL ...

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

    134. Dennis Hill, Photographer April 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP NEAR SPLIT, WITH SUSPENSION BRIDGE IN DISTANT BACKGROUND, FACING EAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  2. 234. Dennis Hill, Photographer July 1998 VIEW OF BUS STOP, ...

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

    234. Dennis Hill, Photographer July 1998 VIEW OF BUS STOP, UPPER DECK OF YERBA BUENA EAST VIADUCT, FACING WEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  3. 125. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL ...

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

    125. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP CROSSING OVER BEALE STREET BETWEEN FOLSOM AND HOWARD STREETS, FACING NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  4. 119. Dennis Hill, Photographer January 1998 VIEW OF UNDERSIDE OF ...

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

    119. Dennis Hill, Photographer January 1998 VIEW OF UNDERSIDE OF UPPER DECK OFF-RAMP AND TRANSBAY TERMINAL BUS LOOP NEAR FOLSOM STREET, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  5. 123. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK ...

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

    123. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK OFF-RAMP DESCENDING TO FREMONT STREET, WITH TRANSBAY TERMINAL BUS LOOP BEHIND, FACING NORTH. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  6. 133. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL ...

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

    133. Dennis Hill, Photographer January 1998 VIEW OF TRANSBAY TERMINAL BUS LOOP FROM HOWARD STREET BETWEEN FIRST AND SECOND STREETS, FACING EAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  7. 128. Dennis Hill, Photographer January 1998 VIEW OF UNDERSIDE OF ...

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

    128. Dennis Hill, Photographer January 1998 VIEW OF UNDERSIDE OF TRANSBAY TERMINAL BUS LOOP CROSSING OVER HOWARD STREET NORTHEAST OF BEALE STREET, FACING NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  8. EXTERIOR, A view looking northwest from far hill toward the ...

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

    EXTERIOR, A view looking northwest from far hill toward the Mounds complex and the HH Building - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  9. 233. Dennis Hill, Photographer April 1998 VIEW OF LOWER DECK ...

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

    233. Dennis Hill, Photographer April 1998 VIEW OF LOWER DECK AND KEY SYSTEM STATION CANOPY, YERBA BUENA EAST VIADUCT, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  10. 215. Dennis Hill, Photographer May 1998 DETAIL VIEW OF STRAND ...

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

    215. Dennis Hill, Photographer May 1998 DETAIL VIEW OF STRAND SHOES AND STORM CABLE EYE BARS IN YERBA BUENA ANCHORAGE, FACING EAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  11. 266. Dennis Hill, Photographer June 1998 DETAIL VIEW OF TENSION ...

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

    266. Dennis Hill, Photographer June 1998 DETAIL VIEW OF TENSION EYE BARS AND COMPRESSION MEMBERS ABOVE UPPER DECK, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  12. 265. Dennis Hill, Photographer April 1998 DETAIL VIEW OF TENSION ...

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

    265. Dennis Hill, Photographer April 1998 DETAIL VIEW OF TENSION EYE BARS AT CANTILEVER TRUSS, FACING SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  13. 22. TRANSMISSION MAIN, PLAN AND PROFILE, INDEX SHEET. Leeds, Hill, ...

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

    22. TRANSMISSION MAIN, PLAN AND PROFILE, INDEX SHEET. Leeds, Hill, Barnard & Jewett drawing, no date, no number. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  14. 23. CUESTA TUNNEL, PORTAL STRUCTURES. Leeds, Hill, Barnard & Jewett ...

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

    23. CUESTA TUNNEL, PORTAL STRUCTURES. Leeds, Hill, Barnard & Jewett drawing, no number, revised 10/10/41. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  15. 12. Historic American Buildings Survey Joseph Hill, Photographer Spring 1937 ...

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

    12. Historic American Buildings Survey Joseph Hill, Photographer Spring 1937 DETAIL OF CORNICE AND SECOND FLOOR WINDOW TRIM. - Rock Island Arsenal, Building No. 346, Davenport Drive, Arsenal Grounds, Rock Island, Rock Island County, IL

  16. 170. Credit SHS. Northern California Power Company substation, Bully Hill ...

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

    170. Credit SHS. Northern California Power Company substation, Bully Hill Mine area. Note lack of vegetation, caused by nearby copper smelting works. - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  17. 24. VIEW FORM NORTHWEST, WHERE HOUSE RECEDES INTO HILL, SHOWING ...

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

    24. VIEW FORM NORTHWEST, WHERE HOUSE RECEDES INTO HILL, SHOWING ROOF, CHIMNEY AND OCTAGONAL SKYLIGHT TO KITCHEN IN CENTER - Isaac N. Hagan House, Kentuck Knob, U.S. Route 40 vicinity (Stewart Township), Chalkhill, Fayette County, PA

  18. 1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 STAIR RAILING, 66 WEST OAK STREET - Chicago Ironwork, 66 West Oak Street (Cast Iron Stair Railing), 66 West Oak Street, Chicago, Cook County, IL

  19. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #12 EARLY RED BRICK HOUSE, Elk and Prospect Sts., Galena, Illinois - Galena Doorways, Red Brick House, Elk & Prospect Streets, Galena, Jo Daviess County, IL

  20. 46. LINED SECTION OF AQUEDUCT LOOKING NORTH TO ALABAMA HILLS ...

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

    46. LINED SECTION OF AQUEDUCT LOOKING NORTH TO ALABAMA HILLS - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  1. 1. Historic American Buildings Survey Joseph Hill, Photographer May 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer May 1936 COPY OF OLD PHOTOGRAPH LOANED BY THE COMMANDANT, EARLY PHOTO OF HOUSE DATE UNKNOWN. - Rock Island Arsenal, Building No. 346, Davenport Drive, Arsenal Grounds, Rock Island, Rock Island County, IL

  2. 1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 COPIED FROM AN OLD PHOTOGRAPH LOANED BY MRS. NELLY MUNRO - Old Baptist Parsonage, Snyder & Virginia Streets, Sublette, Lee County, IL

  3. 1. Historic American Buildings Survey Copied by Joseph Hill from ...

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

    1. Historic American Buildings Survey Copied by Joseph Hill from an old photograph loaned by Alice Snyder, Galena, Illinois. SOUTH EAST ELEVATION - Grace Episcopal Church, South Prospect Street, Galena, Jo Daviess County, IL

  4. 2. Historic American Buildings Survey Copied by Joseph Hill from ...

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

    2. Historic American Buildings Survey Copied by Joseph Hill from photograph loaned by the Illinois Bell Telephone Co. SOUTH EAST ELEVATION - Grace Episcopal Church, South Prospect Street, Galena, Jo Daviess County, IL

  5. 2. Historic American Buildings Survey Joseph Hill, Photographer May 1936 ...

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

    2. Historic American Buildings Survey Joseph Hill, Photographer May 1936 COPY OF AN OLD PHOTOGRAPH LOANED BY THE COMMANDANT, ARSENAL ISLAND 1870 - Rock Island Arsenal, Rock Island, Rock Island County, IL

  6. 1. Historic American Buildings Survey Joseph Hill, Photographer May 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer May 1936 COPY OF PHOTOGRAPH LOANED BY THE COMMANDANT, FORT ARMSTRONG 1819 FROM A MODEL IN ARSENAL MUSEUM - Fort Armstrong, Rock Island, Rock Island County, IL

  7. 19. Historic American Buildings Survey Joseph Hill, Photographer COL. DAVENPORT ...

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

    19. Historic American Buildings Survey Joseph Hill, Photographer COL. DAVENPORT Copy of an old photograph loaned by the commandant. - Rock Island Arsenal, Building No. 346, Davenport Drive, Arsenal Grounds, Rock Island, Rock Island County, IL

  8. 4. Historic American Buildings Survey Joseph Hill, Photographer May 1936 ...

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

    4. Historic American Buildings Survey Joseph Hill, Photographer May 1936 COPY OF OLD PHOTOGRAPH LOANED BY THE COMMANDANT, FORT ARMSTRONG ARSENAL ISLAND 1819 - Fort Armstrong, Rock Island, Rock Island County, IL

  9. 5. Historic American Buildings Survey Joseph Hill, Photographer May 1936 ...

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

    5. Historic American Buildings Survey Joseph Hill, Photographer May 1936 COPY OF OLD PHOTOGRAPH LOANED BY THE COMMANDANT. DATE UNKNOWN - Rock Island Arsenal, Building No. 346, Davenport Drive, Arsenal Grounds, Rock Island, Rock Island County, IL

  10. 1. Historic American Buildings Survey Joseph Hill, Photographer May 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer May 1936 COPY OF AN OLD PHOTOGRAPH LOANED BY THE COMMANDANT, EARLY BRIDGE ACROSS MISSISSIPPI RIVER, DATE UNKNOWN. - Bridge Spanning Mississippi River, Rock Island, Rock Island County, IL

  11. 12. VIEW FROM PARKWAY MEDIAN TO SPORT HILL ROAD BRIDGE, ...

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

    12. VIEW FROM PARKWAY MEDIAN TO SPORT HILL ROAD BRIDGE, Copy of photograph ca. 1940. Collection Connecticut Department of Transportation. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  12. 3. Historic American Buildings Survey Joseph Hill, Photographer August 1936 ...

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

    3. Historic American Buildings Survey Joseph Hill, Photographer August 1936 BRONZE TABLET HISTORICAL MARKER - Hobson Grist Mill (Monument & Millstones), DuPage County Pioneer Park, Naperville, Du Page County, IL

  13. 2. Historic American Buildings Survey Joseph Hill, Photographer July 1936 ...

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

    2. Historic American Buildings Survey Joseph Hill, Photographer July 1936 BALCONY RAILING, 945 NO. DEARBORN ST. JUDGE CARPENTER'S HOME - Chicago Ironwork, Judge Carpenter House (Cast Iron Balcony Railing), 945 North Dearborn Street, Chicago, Cook County, IL

  14. 3. Historic American Buildings Survey Joseph Hill, Photographer June, 1936 ...

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

    3. Historic American Buildings Survey Joseph Hill, Photographer June, 1936 DETAIL OF BALCONY RAILING, 945 NO. DEARBORN ST. JUDGE CARPENTER'S HOME - Chicago Ironwork, Judge Carpenter House (Cast Iron Balcony Railing), 945 North Dearborn Street, Chicago, Cook County, IL

  15. 12. Historic American Buildings Survey Joseph Hill, Photographer July 10, ...

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

    12. Historic American Buildings Survey Joseph Hill, Photographer July 10, 1936 SOUTH ELEVATION (Copied from student's drawing, Dept. of Architecture, Armour Institute of Technology. Chicago) - Keating House, U.S. Highway 430, Fayville, Alexander County, IL

  16. 126. Dennis Hill, Photographer January 1998 DETAIL VIEW OF SUPPORT ...

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

    126. Dennis Hill, Photographer January 1998 DETAIL VIEW OF SUPPORT STRUCTURE FOR TRANSBAY TERMINAL BUS LOOP CROSSING OVER BEALE STREET, FACING WEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  17. 154. Dennis Hill, Photographer April 1998 DETAIL VIEW OF ENTRY ...

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

    154. Dennis Hill, Photographer April 1998 DETAIL VIEW OF ENTRY DOOR TO SAN FRANCISCO ANCHORAGE AT BEALE STREET, FACING SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  18. 158. Dennis Hill, Photographer June 1998 VIEW DOWN BEALE STREET ...

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

    158. Dennis Hill, Photographer June 1998 VIEW DOWN BEALE STREET TOWARD HARRISON STREET BRIDGE, WITH SAN FRANCISCO ANCHORAGE AND CONTINUOUS SPAN IN BACKGROUND, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  19. 305. Dennis Hill, Photographer June 1998 DETAIL VIEW OF UPPER ...

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

    305. Dennis Hill, Photographer June 1998 DETAIL VIEW OF UPPER DECK GUARDRAIL AT DECK TRUSS SPANS, FACING WEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  20. SRTM Anaglyph: Haro and Kas Hills

    NASA Technical Reports Server (NTRS)

    2001-01-01

    On January 26, 2001 the Kachchh region in western India suffered the most deadly earthquake in India's history. This three-dimensional view of landforms northeast of the city of Bhuj depicts geologic structures that are of interest in the study the tectonic processes that may have led to that earthquake. However, preliminary field studies indicate that these structures are composed of Mesozoic rocks that are overlain by younger rocks showing little deformation. Thus these structures may be old, not actively growing, and not directly related to the recent earthquake.

    The Haro Hills are on the left and the Kas Hills are on the right. The Haro Hills are an 'anticline,' which is an upwardly convex elongated fold of layered rocks. The anticline is distinctly ringed by an erosion resistant layer of sandstone. The east-west orientation of the anticline may relate to the crustal compression that has occurred during India's northward movement toward, and collision with, Asia. In contrast, the largest of the Kas Hills appears to be a tilted (to the south) and faulted (on the north) block of layered rocks. Also seen here, the curvilinear ridge trending toward the southwest from the image center is an erosion resistant 'dike,' which is an igneous intrusion into older 'host' rocks along a fault plane or other crack. The dike also appears to extend northeast from the image center as a dark line having very little topography. Its location between the tilted block and a smaller anticline to the north (directly east of the larger anticline) probably indicates that the dike fills the fault that separates these contrasting geologic structures. These features are simple examples of how digital elevation data can stereoscopically enhance satellite imagery to provide a direct input to geologic studies.

    The stereoscopic effect of this anaglyph was created by first draping a Landsat satellite image (taken just two weeks after the earthquake) over preliminary digital elevation

  1. Steamboat Hills exploratory slimhole: Drilling and testing

    SciTech Connect

    Finger, J.T.; Jacobson, F.D.; Hickox, C.E.; Eaton, R.R.

    1994-10-01

    During July-September, 1993, Sandia National Laboratories, in cooperation with Far West Capital, drilled a 4000 feet exploratory slimhole (3.9 inch diameter) in the Steamboat Hills geothermal field near Reno, Nevada. This well was part of Sandia`s program to evaluate slimholes as a geothermal exploration tool. During and after drilling the authors performed four series of production and injection tests while taking downhole (pressure-temperature-spinner) and surface (wellhead pressure and temperature, flow rate) data. In addition to these measurements, the well`s data set includes: continuous core (with detailed log); borehole televiewer images of the wellbore`s upper 500 feet; daily drilling reports from Sandia and from drilling contractor personnel; daily drilling fluid record; numerous temperature logs; and comparative data from production and injection wells in the same field. This report contains: (1) a narrative account of the drilling and testing, (2) a description of equipment used, (3) a brief geologic description of the formation drilled, (4) a summary and preliminary interpretation of the data, and (5) recommendations for future work.

  2. Bunker Hill Superfund site: Ecological restoration program

    SciTech Connect

    Brown, S.; Chaney, R.; Henry, C.L.; Compton, H.

    1998-12-31

    Bunker Hill ID was the site of mining and smelting activities for many decades. As a result of these activities, soils on the hillsides adjacent to the site became contaminated with Pb, Zn, and Cd. In addition to metal contamination, pH of the soils became highly acidic. Native vegetation has died off and the soils have become highly erosive. An application of municipal biosolids in combination with wood ash and log yard wood waste was made to test the potential of this remediation mixture to reduce erosion, correct soil pH, and support a self sustaining vegetative cover. Biosolids improve soil physical properties and provide macro and micro nutrients. Wood ash serves as a lime substitute and a source of nutrients. Log yard waste improves physical properties and has a high C:N ratio that reduces the potential for N leaching. Initial results are promising. A healthy stand of grasses and legumes has been established. In addition, the application mixture has proven itself to be highly resistant to erosion.

  3. After runaway: The trans-Hill stage of planetesimal growth

    SciTech Connect

    Lithwick, Yoram

    2014-01-01

    When planetesimals begin to grow by coagulation, they first enter an epoch of runaway, during which the biggest bodies grow faster than all the others. The questions of how runaway ends and what comes next have not been answered satisfactorily. We show that runaway is followed by a new stage—the 'trans-Hill stage'—that commences when the bodies that dominate viscous stirring ('big bodies') become trans-Hill, i.e., when their Hill velocity matches the random speed of the small bodies they accrete. Subsequently, the small bodies' random speed grows in lockstep with the big bodies' sizes, such that the system remains in the trans-Hill state. Trans-Hill growth is crucial for determining the efficiency of growing big bodies, as well as their growth timescale and size spectrum. Trans-Hill growth has two sub-stages. In the earlier one, which occurs while the stirring bodies remain sufficiently small, the evolution is collisionless, i.e., collisional cooling among all bodies is irrelevant. The efficiency of forming big bodies in this collisionless sub-stage is very low, ∼10α << 1, where α ∼ 0.005(a/AU){sup –1} is the ratio between the physical size of a body and its Hill radius. Furthermore, the size spectrum is flat (equal mass per size decade, i.e., q = 4). This collisionless trans-Hill solution explains results from previous coagulation simulations for both the Kuiper Belt and the asteroid belt. The second trans-Hill sub-stage commences once the stirring bodies grow big enough (>α{sup –1} × the size of the accreted small bodies). After that time, collisional cooling among small bodies controls the evolution. The efficiency of forming big bodies rises and the size spectrum becomes more top heavy. Trans-Hill growth can terminate in one of two ways, depending on the sizes of the small bodies. First, mutual accretion of big bodies can become significant and conglomeration proceeds until half of the total mass is converted into big bodies. This mode of growth

  4. Stormwater Management Plan for the Arden Hills Army Training Site, Arden Hills, Minnesota

    SciTech Connect

    Carr, Adrianne E.; Wuthrich, Kelsey K.; Ziech, Angela M.; Bowen, Esther E.; Quinn, John

    2013-03-01

    This stormwater management plan focuses on the cantonment and training areas of the Arden Hills Army Training Site (AHATS). The plan relates the site stormwater to the regulatory framework, and it summarizes best management practices to aide site managers in promoting clean site runoff. It includes documentation for a newly developed, detailed model of stormwater flow retention for the entire AHATS property and adjacent upgradient areas. The model relies on established modeling codes integrated in a U.S. Department of Defense-sponsored software tool, the Watershed Modeling System (WMS), and it can be updated with data on changes in land use or with monitoring data.

  5. Reconstructing Younger Dryas plateau icefields in the Tweedsmuir Hills, Southern Uplands, Scotland: Style, dynamics and palaeo-climatic implications

    NASA Astrophysics Data System (ADS)

    Pearce, Danni; Rea, Brice; Bradwell, Tom; Barr, Iestyn; Small, David; McDougall, Des

    2014-05-01

    In Britain, the glacial geomorphological record has been widely utilised to infer palaeo-glacier geometries and ice dynamics, with much of this work focusing on the Scottish Highlands during the Last Glacial Interglacial Transition (LGIT), in particular the Younger Dryas (YD; c. 12.9 - 11.7 ka BP). The Southern Uplands represents the largest upland area south of the Highlands but has received limited research attention over the last century. The Tweedsmuir Hills are located in the central Southern Uplands, which form an area of dissected plateau approximately 320 km2. Early research in the 1800s identified moraines thought to be associated with the YD. However, the majority of previous work has focussed on isolated valleys and ignored the potential for plateau icefield glaciation, which has significant implications for the understanding of ice dynamics and geometries. Recent numerical modelling experiments covering the period 38 - 10.4 ka BP (Hubbard et al., 2008 cf. E109B8 and E102b2) have predicted a significant body of ice for the Southern Uplands at the onset of and throughout the YD, which cannot be verified at present due to a lack of empirical data. This research aims to provide the first systematic geomorphological mapping and Lateglacial climate reconstruction for the Tweedsmuir Hills. The results of air-photo interpretation and field mapping, which utilised a morphostratigraphic approach, have demonstrated a more extensive glaciation than previously mapped, reflecting more closely the Hubbard et al. (2009) modelled extent than earlier research. This consists of two separate icefields over the southern and northern Tweedsmuir Hills covering an area c. 45 km2 and 25 km2 respectively with Equilibrium Line Altitudes (ELAs) calculated to have ranged from c.419 m to 634 m. For both icefields ELAs of individual outlets reflect topographic controls rather than steep precipitation gradients similar to those derived for other icefields in Scotland (e.g., the

  6. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...). (3) “Los Alamos, Calif.,” edition of 1959. (4) “Santa Rosa Hills, Calif.,” edition of 1959... the heart of the Santa Rosa Land Grant, T.7N., R. 32W, on the Santa Rosa Hills, Calif., Quadrangle U.S... the northeastern part of the Santa Rosa Land Grant, T.7N, R. 32W, on the Los Alamos,...

  7. 1. General view of Fort Hill Farm, view looking southsoutheast. ...

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

    1. General view of Fort Hill Farm, view looking south-southeast. From left to right, buildings visible are (B) two-story hall-and-parlor house; (k) small barn; (A) mansion' (G( shed; (H) shed; (I) log tobacco barn; (H and D) shed and center chimney four-room cabin; (E and (A) one-room cabin in front of mansion; (J) hay barn. - Fort Hill Farm, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  8. 2. General view of Fort Hill Farm, view looking north ...

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

    2. General view of Fort Hill Farm, view looking north from (F) two-room cabin. From left to right, buildings visible are (I) log tobacco barn; (H and D) shed and center chimney four-room cabin; (E and (A) one-room cabin in front of mansion; (J) hay barn. - Fort Hill Farm, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  9. 3. General view of Fort Hill Farm, view looking west ...

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

    3. General view of Fort Hill Farm, view looking west from (B) two-story hall-and-parlor house. Buildings visible, from left to right, are (B) parlor house porch; (E) one-room cabin; (D) center chimney four-room cabin; (J) hay barn; (I) log tobacco barn; (A) mansion, obscured by trees; (M) stable; (K) small barn. - Fort Hill Farm, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  10. 4. BUNKER HILL LEAD SMELTER. VIEW IS FROM RIDGE ABOVE ...

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

    4. BUNKER HILL LEAD SMELTER. VIEW IS FROM RIDGE ABOVE GOVERNMENT GULCH LOOKING TO THE EAST. IN THE RIGHT MID GROUND, CARPENTER SHOP BUILDINGS AND FRAMING SHEDS ARE VISIBLE. THE BACKGROUND FACILITIES VISIBLE FROM L. TO R. ARE: SMELTER OFFICE, REFINERIES, SLAG FUMING STACKS, HIGH VELOCITY FLUE, BAG HOUSE, 200-FOOT STACK, AND 715-FOOT STACK. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  11. Water Quality Studies: Richard B. Russell and Clarks Hill Lakes.

    DTIC Science & Technology

    1986-12-01

    studies at Richard B. Russell and Clarks Hill lakes , Georgia and South Carolina. The study objectives were to document water quality conditions in each...Monitoring Program - Richard B. Russell Dam and Lake , Georgia and South Carolina" (Intra-Army Order No. PD-EI-84-07). Portions of these studies were...by the U. S. Army Corps of Engi- neers, is situated between Hartwell and Clarks Hill Lakes . 7. Concerns over the potential environmental and water

  12. SOUTH ELEVATION OF GOLD HILL MILL, LOOKING NORTH. THE PRIMARY ...

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

    SOUTH ELEVATION OF GOLD HILL MILL, LOOKING NORTH. THE PRIMARY ORE BIN IS A CENTER, WITH A JAW CRUSHER JUST TO THE RIGHT. A CONVEYOR (MISSING) WAS USED TO CARRY CRUSHED ORE UP AND INTO THE SECONDARY ORE BIN. THE STONE RAMP TO THE LEFT OF THE ORE BIN WAS USED TO DRIVE TRUCKS UP TO DUMPING LEVEL. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  13. Greenland Ice Flow

    NASA Video Gallery

    Greenland looks like a big pile of snow seen from space using a regular camera. But satellite radar interferometry helps us detect the motion of ice beneath the snow. Ice starts flowing from the fl...

  14. A 7-month-old male with Allan-Herndon-Dudley syndrome and the power of T3.

    PubMed

    Langley, Katherine G; Trau, Steven; Bean, Lora J H; Narravula, Alekhya; Schrier Vergano, Samantha A

    2015-05-01

    Allan-Herndon-Dudley syndrome (AHDS, MIM 300523) is an X-linked neurodegenerative disorder characterized by intellectual disability, severe hypotonia, diminished muscle mass, and progressive spastic paraplegia. All affected males have pathognomonic thyroid profiles with an elevated T3 , low-normal free T4 , and normal TSH. Mutations in the monocarboxylate transporter 8 (MCT8) gene, SLC16A2, have been found to be causative. Here, we describe a proband whose extensive evaluation and ultimate diagnosis of AHDS unmasked three previously undiagnosed generations of affected individuals in one family. This case illustrates the need for clinicians to consider obtaining full thyroid studies on individuals with the non-specific findings of severe hypotonia, failure to thrive, and gross motor delay.

  15. The final days of Edgar Allan Poe: clues to an old mystery using 21st century medical science.

    PubMed

    Francis, Roger A

    This study examines all documented information regarding the final days and death of Edgar Allan Poe (1809-1849), in an attempt to determine the most likely cause of death of the American poet, short story writer, and literary critic. Information was gathered from letters, newspaper accounts, and magazine articles written during the period after Poe's death, and also from biographies and medical journal articles written up until the present. A chronology of Poe's final days was constructed, and this was used to form a differential diagnosis of possible causes of death. Death theories over the last 160 years were analyzed using this information. This analysis, along with a review of Poe's past medical history, would seem to support an alcohol-related cause of death.

  16. Ice electrode electrolytic cell

    DOEpatents

    Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

    1993-04-06

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  17. Ice electrode electrolytic cell

    DOEpatents

    Glenn, David F.; Suciu, Dan F.; Harris, Taryl L.; Ingram, Jani C.

    1993-01-01

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  18. Geologic and paleoecologic studies of the Nebraska Sand Hills

    USGS Publications Warehouse

    Ahlbrandt, Thomas S.; Fryberger, S.G.; Hanley, John H.; Bradbury, J. Platt

    1980-01-01

    PART A: The Nebraska Sand Hills are an inactive, late Quaternary, most probably Holocene, dune field (covering 57,000 km 2 ) that have been eroded along streams and in blowouts, resulting in excellent lateral and vertical exposures of the stratification of dune and interdune sediments. This paper presents new data on the geometry, primary sedimentary structures, modification of sedimentary structures, direction of sand movement, and petrography of these eolian deposits. Eolian deposits of the Sand Hills occur as relatively thin (9-24 m) 'blanket' sands, composed of a complex of dune and discontinuous, diachronous interdune deposits unconformably overlying fluviolacustrine sediments. The internal stratification of large dunes in the Sand Hills (as high as 100 m), is similar to the internal stratification of smaller dunes of the same type in the Sand Hills, differing only in scale. Studies of laminae orientation in the Sand Hills indicate that transverse, barchan, and blowout dunes can be differentiated in rocks of eolian origin using both the mean dip angle of laminae and the mean angular deviation of dip direction. A variety of secondary structures modify or replace primary eolian stratification in the Sand Hills, the more common of which are dissipation structures and bioturbation. Dissipation structures in the Sand Hills may develop when infiltrating water deposits clay adjacent to less permeable layers in the sand, or along the upper margins of frozen layers that form in the sands during winter. Cross-bed measurements from dunes of the Nebraska Sand Hills necessitate a new interpretation of the past sand transport directions. The data from these measurements indicate a general northwest-to-southeast drift of sand, with a more southerly drift in the southeast part of the Sand Hills. A large area of small dunes < 100 m high) described by Smith (1965) as linear or seif in the central part of the Sand Hills was interpreted by him on the basis of morphology only. We

  19. Technology for Ice Rinks

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Ron Urban's International Ice Shows set up portable ice rinks for touring troupes performing on temporary rinks at amusement parks, sports arenas, dinner theaters, shopping malls and civic centers. Key to enhanced rink portability, fast freezing and maintaining ice consistency is a mat of flexible tubing called ICEMAT, an offshoot of a solar heating system developed by Calmac, Mfg. under contract with Marshall.

  20. The Antarctic Ice.

    ERIC Educational Resources Information Center

    Radok, Uwe

    1985-01-01

    The International Antarctic Glaciological Project has collected information on the East Antarctic ice sheet since 1969. Analysis of ice cores revealed climatic history, and radar soundings helped map bedrock of the continent. Computer models of the ice sheet and its changes over time will aid in predicting the future. (DH)

  1. Ice Formation on Wings

    NASA Technical Reports Server (NTRS)

    Ritz, L

    1939-01-01

    This report makes use of the results obtained in the Gottingen ice tunnel in which the atmospheric conditions are simulated and the process of ice formation photographed. The effect of ice formation is threefold: 1) added weight to the airplane; 2) a change in the lift and drag forces; 3) a change in the stability characteristics.

  2. Ice Cream Headaches

    MedlinePlus

    Diseases and Conditions Ice cream headaches By Mayo Clinic Staff Ice cream headaches are brief, stabbing headaches that can happen when you eat, drink or inhale something cold. Digging into an ice cream cone is a common trigger, but eating or ...

  3. Ice Versus Rock

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Olson, Eric A.; Dehm, Janet

    2005-01-01

    During a snow bank exploration, students noticed "ice caves," or pockets, in some of the larger snow banks, usually below darker layers. Most of these caves had many icicles hanging inside. Students offered reasonable explanations of ice cave formation--squirrels, kids, snow blowers--and a few students came close to the true ice cave-formation…

  4. Experiments in Ice Physics.

    ERIC Educational Resources Information Center

    Martin, P. F.; And Others

    1978-01-01

    Describes experiments in ice physics that demonstrate the behavior and properties of ice. Show that ice behaves as an ionic conductor in which charge is transferred by the movement of protons, its electrical conductivity is highly temperature-dependent, and its dielectric properties show dramatic variation in the kilohertz range. (Author/GA)

  5. Stargazing at 'Husband Hill Observatory' on Mars

    NASA Technical Reports Server (NTRS)

    2005-01-01

    NASA's Mars Exploration Rover Spirit continues to take advantage of extra solar energy by occasionally turning its cameras upward for night sky observations. Most recently, Spirit made a series of observations of bright star fields from the summit of 'Husband Hill' in Gusev Crater on Mars. Scientists use the images to assess the cameras' sensitivity and to search for evidence of nighttime clouds or haze. The image on the left is a computer simulation of the stars in the constellation Orion. The next three images are actual views of Orion captured with Spirit's panoramic camera during exposures of 10, 30, and 60 seconds.

    Because Spirit is in the southern hemisphere of Mars, Orion appears upside down compared to how it would appear to viewers in the Northern Hemisphere of Earth. 'Star trails' in the longer exposures are a result of the planet's rotation. The faintest stars visible in the 60-second exposure are about as bright as the faintest stars visible with the naked eye from Earth (about magnitude 6 in astronomical terms). The Orion Nebula, famous as a nursery of newly forming stars, is also visible in these images. Bright streaks in some parts of the images aren't stars or meteors or unidentified flying objects, but are caused by solar and galactic cosmic rays striking the camera's detector. Spirit acquired these images with the panoramic camera on Martian day, or sol, 632 (Oct. 13, 2005) at around 45 minutes past midnight local time, using the camera's broadband filter (wavelengths of 739 nanometers plus or minus 338 nanometers).

  6. Alaska marine ice atlas

    SciTech Connect

    LaBelle, J.C.; Wise, J.L.; Voelker, R.P.; Schulze, R.H.; Wohl, G.M.

    1982-01-01

    A comprehensive Atlas of Alaska marine ice is presented. It includes information on pack and landfast sea ice and calving tidewater glacier ice. It also gives information on ice and related environmental conditions collected over several years time and indicates the normal and extreme conditions that might be expected in Alaska coastal waters. Much of the information on ice conditions in Alaska coastal waters has emanated from research activities in outer continental shelf regions under assessment for oil and gas exploration and development potential. (DMC)

  7. Ice Observation Handbook, 1984

    DTIC Science & Technology

    1984-01-01

    which is navigable by surface vessels. Flaw polynya : A polynya between drift ice and fast ice. Floating ice: Any form of ice found floating in water...10 to 6/10 with many leads and polynyas , and the floes are generally not in contact with one another. Open water: A large area of freely navigable...the surface; its appearance may rapidly cover wide areas of water. 9l 2-9 7-7 Polynya : Any non-linear shaped opening enclosed in ice. Polynyas may

  8. Deposition and immersion-mode nucleation of ice by three distinct samples of volcanic ash

    NASA Astrophysics Data System (ADS)

    Schill, G. P.; Genareau, K.; Tolbert, M. A.

    2015-07-01

    Ice nucleation of volcanic ash controls both ash aggregation and cloud glaciation, which affect atmospheric transport and global climate. Previously, it has been suggested that there is one characteristic ice nucleation efficiency for all volcanic ash, regardless of its composition, when accounting for surface area; however, this claim is derived from data from only two volcanic eruptions. In this work, we have studied the depositional and immersion freezing efficiency of three distinct samples of volcanic ash using Raman microscopy coupled to an environmental cell. Ash from the Fuego (basaltic ash, Guatemala), Soufrière Hills (andesitic ash, Montserrat), and Taupo (Oruanui eruption, rhyolitic ash, New Zealand) volcanoes were chosen to represent different geographical locations and silica content. All ash samples were quantitatively analyzed for both percent crystallinity and mineralogy using X-ray diffraction. In the present study, we find that all three samples of volcanic ash are excellent depositional ice nuclei, nucleating ice from 225 to 235 K at ice saturation ratios of 1.05 ± 0.01, comparable to the mineral dust proxy kaolinite. Since depositional ice nucleation will be more important at colder temperatures, fine volcanic ash may represent a global source of cold-cloud ice nuclei. For immersion freezing relevant to mixed-phase clouds, however, only the Oruanui ash exhibited appreciable heterogeneous ice nucleation activity. Similar to recent studies on mineral dust, we suggest that the mineralogy of volcanic ash may dictate its ice nucleation activity in the immersion mode.

  9. How does the Porosity of Interstellar Ice Affect Chemical Complexity and Deuteration Exchange?

    NASA Astrophysics Data System (ADS)

    Fraser, Helen Jane; Noble, Jennifer; Hill, Catherine Rachel; Bowron, Daniel; Youngs, Tristan; Loerting, Thomas; Mitteldorfer, Christian; Millar, James; Elkind, Pavel; Cousan, Stephane; Lui, Yuan; Ojamae, Lars

    2015-08-01

    The porosity of interstellar water ice, Amorphous Solid Water (ASW), greatly enhances the ability of ice to uptake, then release small gas adsorbates. This provides the strongest evidence that interstellar ices must be porous, accounting for the differences between predicted and observed gas-phase abundances, and provides a mechanism to enhance reagent diversity for complex chemistry in the ice. However, no dangling OH (d-OH) bond features, to-date associated with ice porosity, have been reported in interstellar ice spectra, so some conclude that interstellar ices must be non-porous, given that the d-OH spectra disappear in laboratory studies when ASW is energetically processed. But are d-OH features and gas-uptake reliable experimental measures of ice porosity? Here we combine fundamental studies of ASW with observational data to determine ASW porosity and understand its role in the chemical evolution of interstellar ices.We show upper-limit detections of d-OH in observational spectra towards a handful of sources (Fraser et al (2015)). Laboratory experiments on selective irradiation of d-OH features (Noble et al (2013), (2014)), combined with quantum chemical calculations (Lui et al (2015)), show that the d-OH bonds probe the density of defect sites in the surface and sub-surface structure. Consequently surfaces with d-OH bonds are significantly more reactive and therefore promote chemical complexity across extra-terrestrial regions where they are found, but do not reflect ice porosity.Our neutron scattering data show that ASW ices actually contain cylindrical pores of around 10 Å diameter (Mitteldorfer et al (2014)). The pore collapse process can only be initiated by long range molecular diffusion at T > 121 K, and follows complex kinetics (Hill et al (2015a); such effects can be reproduced by molecular dynamics simulations of ASW ice-heating (Elkind et al (2015): Miller et al (2015)), and are directly linked to deuteration exchange. We explain the implications

  10. Arctic ice management

    NASA Astrophysics Data System (ADS)

    Desch, Steven J.; Smith, Nathan; Groppi, Christopher; Vargas, Perry; Jackson, Rebecca; Kalyaan, Anusha; Nguyen, Peter; Probst, Luke; Rubin, Mark E.; Singleton, Heather; Spacek, Alexander; Truitt, Amanda; Zaw, Pye Pye; Hartnett, Hilairy E.

    2017-01-01

    As the Earth's climate has changed, Arctic sea ice extent has decreased drastically. It is likely that the late-summer Arctic will be ice-free as soon as the 2030s. This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean. It is unlikely that CO2 levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative. Here we investigate a means for enhancing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface, where it will freeze more rapidly. We show that where appropriate devices are employed, it is possible to increase ice thickness above natural levels, by about 1 m over the course of the winter. We examine the effects this has in the Arctic climate, concluding that deployment over 10% of the Arctic, especially where ice survival is marginal, could more than reverse current trends of ice loss in the Arctic, using existing industrial capacity. We propose that winter ice thickening by wind-powered pumps be considered and assessed as part of a multipronged strategy for restoring sea ice and arresting the strongest feedbacks in the climate system.

  11. ICE SLURRY APPLICATIONS

    PubMed Central

    Kauffeld, M.; WANG, M. J.; Goldstein, V.; Kasza, K. E.

    2011-01-01

    The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology. PMID:21528014

  12. Blue-ice moraines in Antarctica: long-term formation and short-term change

    NASA Astrophysics Data System (ADS)

    Woodward, J.; Dunning, S.; Sugden, D.; Hein, A.; Marrero, S.

    2013-12-01

    The Heritage Range at the southern end of the Ellsworth Mountains lies across the main flow of the West Antarctic Ice Sheet (WAIS) just 50 km from the grounding line of the Filchner-Ronne Ice Shelf. If the long-term record of ice sheet change can be understood from the Blue Ice Moraines (BIM) found along the hills it becomes a critical location to understand the past behaviour of the ice sheet, and therefore, to better understand the future behaviour of WAIS in a warming climate. We present integrated geophysical data from Unmanned Aerial Vehicles (UAV), Terrestrial Laser Scanning (TLS) and ground penetrating radar (GPR) that helps us understand the long-term formation, and short-term mophological changes of BIMs. BIMs along the front of Patriot Hills (part of the Heritage Range) are associated with katabatic winds enhancing ablation and sublimation to create depressions that are then compensated for by ice-flow from the main trunk glacier at right angles to the main flow direction. This ice flow brings basal debris from the trunk glacier that can reside for long-periods of time rather than being removed by the dominant mountain parallel ice-flow. Using GPR we have imaged debris bands from the trunk glacier arriving directly into the lowest BIMs, and also emerging at the ice surface as folded debris bands in the moraine-marginal depressions that do not have a dense enough debris cover to prevent ablation. High resolution elevation models derived from TLS, and a UAV quantify the changing topography associated with this debris arriving into the BIM, and the surface change over a summer melt season. This work was funded by NERC Standard Grant NE/I025840/1

  13. Large scale spatial variation of accumulation rate across ice promontory in coastal Dronning Maud Land, Antarctica.

    NASA Astrophysics Data System (ADS)

    Callens, Denis; Matsuoka, Kenichi; Drews, Reinhard; Pattyn, Frank

    2013-04-01

    Ice rises are known to play a key role on ice shelf dynamics. By buttressing the flow, they constrain the flow of ice from the continent toward the ocean. However, since they are small hills surrounded by extremely flat area, they also play a role on atmospheric circulation. However, this impact is relatively unknown. Here, we show evidence that ice rises play a significant role on the wind redistribution of the snow. We report observations of persistent features observed all around the coast of Dronning Maud Land (DML). By analyzing radio-echo sounding data, we identified internal reflection horizons assumed to be isochronous. These layers show a remarkable variability in layer depth at both sides of the ridge, pointing to variability in surface accumulation rates. We show that a strong gradient of accumulation rate exist across, at least, 5 different ice rises in DML : Halvfarryggen Ice Rise nearby Ekstromisen (7°W), 2 ice rises into the Fimbulisen (2°E) and 2 ice rises within the Roi Baudoin Ice Shelf (25°E, Derwael & FranKenny Ice Rise). We used deepness of radar reflector as a proxy of the accumulation rate as long as we removed the influence of ice dynamics. All collected data (both low and high frequency) all show the similar persistent gradient in accumulation rate. Comparison of accumulation rate distribution and meteorological data shows that accumulation rate is twice as high on the wind side of the ridge compared to the lee side, which makes ice rise topography playing a significant role in snow redistribution. This feature is important in term of ice coring and paleoclimatic reconstruction of on time scales of 2 to 20k years.

  14. Landscape formation by past continental ice sheets: insights into the subglacial environment

    NASA Astrophysics Data System (ADS)

    Piotrowski, Jan A.

    2014-05-01

    Glaciers and ice sheets are known as most powerful, climatically driven agents of large-scale sediment redistribution and landscape formation in the Earth system. During the Quaternary, repeated waxing and waning of continental ice sheets contributed to profound reshaping of the Earth surface and set the scene for the development of ecosystems in the post-glacial time. Despite the well-established impact of glaciers on the upper lithosphere the specific processes of glacial erosion, transport and deposition and the formation landforms at the ice-bed interface are contentious. In particular, the relative importance of direct ice impact versus the impact of glacial meltwater is highly controversial. Here, we focus on the southern peripheral area of the Scandinavian Ice Sheet hosting thick successions of soft, deformable sediments and examine some spectacular sediment/landform assemblages found nowadays in both terrestrial and marine settings to illustrate the nature of the subglacial processes. In order to decipher the past ice sheet behavior field, experimental and numerical approaches are combined. It is shown that the strength of the coupling between the ice and the bed that controls the response of the substratum to ice overriding and stress propagation depends primarily on the ability of the glacial system to evacuate meltwater from ice-bed interface. Strong coupling, locally enhanced by subglacial permafrost resulted in deeply rooted (100's of meters) glaciotectonic deformation reflected on the surface as ice-shoved hills whereas weak coupling promoted by water accumulating under the ice triggered the formation of deep (100's of meters) tunnel valley networks. Under the arteries of fast-flowing ice known as palaeo-ice streams, remoulding of soft sediments generated mega-scale glacial lineations and drumlins that hold the key to understanding glacier dynamics. The subglacial environment is envisaged as a four-dimensional mosaic of stable and deforming spots

  15. Of Ice and Microbes

    NASA Astrophysics Data System (ADS)

    Deming, Jody

    2006-12-01

    Inuit hunters of the North have long recognized ice as the natural state of water from which life flows on Earth. Although unaware of the microscopic world, they chart changes in properties of ice and water that derive from a succession of microbial inhabitants. Scientific hunters of the West have largely overlooked all but the warmest of ices as dynamic scenes of microbial life, considering the frozen realm to archive life forms instead. Deeply frozen glacial ice on Earth does appear to preserve microbes effectively, but isn't the ocean beneath the geologically dynamic ice of Europa believed too salty? Aren't the subsurface ices of Mars expected to be rich in all manner of mineralogical impurities? Wherever salt and other mineral impurities are sufficiently abundant in Earth ice, the ice contains interior liquid water that can range from nano-layer films on grain surfaces (glacial ice) to a porous network of brine (Arctic winter sea ice down to 20°C). Other recent studies of saline ices have indicated a world of interacting life forms, with viruses infecting bacteria in brines at -12°C (the lowest temperature tested), the domains of Bacteria and Archaea undergoing succession in winter ices (down to -28°C), and evidence that cellular maintenance may go forward incrementally even below the eutectic of seawater (-55°C). Microbes are also known to alter the physical properties of their icy homes by producing exopolymers that further depress the freezing point, either directly or by entraining more salt into the ice. Even the most inhospitable of ices to human hunters may contain interior oases for microbes, in control to some degree of their own space. In considering the habitability of icy worlds beyond Earth, we'd do well to learn more about the evolutionary prowess of microbes in adapting to conditions beyond our warm-blooded imaginations.

  16. Arctic landfast sea ice

    NASA Astrophysics Data System (ADS)

    Konig, Christof S.

    Landfast ice is sea ice which forms and remains fixed along a coast, where it is attached either to the shore, or held between shoals or grounded icebergs. Landfast ice fundamentally modifies the momentum exchange between atmosphere and ocean, as compared to pack ice. It thus affects the heat and freshwater exchange between air and ocean and impacts on the location of ocean upwelling and downwelling zones. Further, the landfast ice edge is essential for numerous Arctic mammals and Inupiat who depend on them for their subsistence. The current generation of sea ice models is not capable of reproducing certain aspects of landfast ice formation, maintenance, and disintegration even when the spatial resolution would be sufficient to resolve such features. In my work I develop a new ice model that permits the existence of landfast sea ice even in the presence of offshore winds, as is observed in mature. Based on viscous-plastic as well as elastic-viscous-plastic ice dynamics I add tensile strength to the ice rheology and re-derive the equations as well as numerical methods to solve them. Through numerical experiments on simplified domains, the effects of those changes are demonstrated. It is found that the modifications enable landfast ice modeling, as desired. The elastic-viscous-plastic rheology leads to initial velocity fluctuations within the landfast ice that weaken the ice sheet and break it up much faster than theoretically predicted. Solving the viscous-plastic rheology using an implicit numerical method avoids those waves and comes much closer to theoretical predictions. Improvements in landfast ice modeling can only verified in comparison to observed data. I have extracted landfast sea ice data of several decades from several sources to create a landfast sea ice climatology that can be used for that purpose. Statistical analysis of the data shows several factors that significantly influence landfast ice distribution: distance from the coastline, ocean depth, as

  17. Hydrology of the Black Hills area, South Dakota

    USGS Publications Warehouse

    Driscoll, Daniel G.; Carter, Janet; Williamson, Joyce; Putnam, Larry

    2002-01-01

    The Black Hills Hydrology Study was initiated in 1990 to assess the quantity, quality, and distribution of surface water and ground water in the Black Hills area of South Dakota. This report summarizes the hydrology of the Black Hills area and the results of this long-term study.The Black Hills area of South Dakota and Wyoming is an important recharge area for several regional, bedrock aquifer systems and various local aquifers; thus, the study focused on describing the hydrologic significance of selected bedrock aquifers. The major aquifers in the Black Hills area are the Deadwood, Madison, Minnelusa, Minnekahta, and Inyan Kara aquifers. The highest priority was placed on the Madison and Minnelusa aquifers, which are used extensively and heavily influence the surface-water resources of the area.Within this report, the hydrogeologic framework of the area, including climate, geology, ground water, and surface water, is discussed. Hydrologic processes and characteristics for ground water and surface water are presented. For ground water, water-level trends and comparisons and water-quality characteristics are presented. For surface water, streamflow characteristics, responses to precipitation, annual yields and yield efficiencies, and water-quality characteristics are presented. Hydrologic budgets are presented for ground water, surface water, and the combined ground-water/surface-water system. A summary of study findings regarding the complex flow systems within the Madison and Minnelusa aquifers also is presented.

  18. Water quality in the vicinity of Fenton Hill, 1987 and 1988. [Fenton Hill site

    SciTech Connect

    Purtymun, W.D.; Ferenbaugh, R.W.; Maes, M.N.; Williams, M.C.

    1991-03-01

    Water-quality data have been collected since 1974 from established surface- and ground-water stations at, and in the vicinity of, Fenton Hill (site of the Laboratory's Hot Dry Rock Geothermal Project). The site is located on the southwest edge of the Valles Caldera in the Jemez Mountains. To determine the chemical quality of water, data were collected in 1987 and 1988 from 13 surface-water stations and 19 ground-water stations. The classification of the water quality is made on the basis of predominated ions and total dissolved solids. There are four classifications of surface water (sodium and chloride, calcium and bicarbonate, calcium and sulfate, and sodium and bicarbonate) and three classifications of ground water (sodium and chloride, calcium and bicarbonate, and sodium and bicarbonate). Variations in the chemical quality of the surface and ground water in 1987 and 1988 are apparent when data are compared with each other and with previous analyses. These variations are not considered significant, as they are in the range of normal seasonal changes. Cumulative production since 1976 from the supply well at Fenton Hill has been about 63 {times} 10{sup 6} gal, with a decline in the water level of the well of about 14 ft, or about 1.4 ft/yr. The aquifer penetrated by the well is still capable of reliable supply to the site for a number of years, based on past production. The quality of water from the well has deteriorated slightly; however, the water quality is in compliance with drinking water standards. The effects of discharge from the storage ponds into an adjacent canyon have been monitored by trace metal analyses of vegetation and soil. The study indicates minimal effects, which will be undetectable in a few years if there are no further releases of effluents into the canyon. 19 refs., 6 figs., 3 tabs.

  19. Ice flow of the Antarctica Ice Sheet

    NASA Astrophysics Data System (ADS)

    Mouginot, J.; Scheuchl, B.; Rignot, E. J.

    2011-12-01

    Ice velocity is fundamental characteristic of the dynamics of ice sheets and is essential to know for calculating the mass budget of ice sheet and for controlling ice sheet numerical models with realistic boundary conditions. Until recently, data were mostly available on a discrete basis over small areas with variable precision. Here, we report on our results of processing ice velocity from the interferometric synthetic-aperture radar data acquired by ALOS PALSAR in 2006 to 2010 by the Japan Aerospace Exploration Agency (JAXA), by ENVISAT ASAR in 2007 to 2009, by RADARSAT-2 in 2009 and 2011, by RADARSAT-1 in 1997 and 2000 and by ERS-1 & -2 in 1996 in the framework of the International Polar Year 2007-2009. The result is the most comprehensive and precise high-resolution digital map of ice motion ever produced on the Antarctic continent. While important surprises are found along the coastline, it is in the interior that this map is revealing the most interesting features. The data reveal widespread, patterned, enhanced flow with tributary glaciers reaching hundreds to thousands of kilometers inland, over the entire continent. We show that the ice motion along these flow features has a strong basal slip component. This has far reaching implications for the modeling of ice sheet flow and evolution. In addition, our multi-year coverage of the coastal sectors reveal the beginning of an acceleration on Thwaites glacier and a wave of accelerated flow propagating inland rapidly on Pine Island Glacier between 2006 and 2010. This work was conducted at the Department of Earth System Science, University of California Irvine under a contract with the National Aeronautics and Space Administration's MEaSUREs program.

  20. Sunlight, Sea Ice, and the Ice Albedo Feedback in a Changing Arctic Sea Ice Cover

    DTIC Science & Technology

    2013-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Sunlight, Sea Ice, and the Ice Albedo Feedback in a...ice age, and iv) onset dates of melt and freezeup. 4. Assess the magnitude of the contribution from ice- albedo feedback to the observed decrease of...COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Sunlight, Sea Ice, and the Ice Albedo Feedback in a Changing Arctic Sea Ice Cover 5a

  1. Consider an Ice Stream.

    NASA Astrophysics Data System (ADS)

    Bindschadler, R.

    2002-12-01

    Forty years ago, John Nye was one of the leaders who introduced the rigors of classical physics to glaciology. His elegant treatments frequently took advantage of the then recent discovery that ice could be approximated as a plastic material. With this viewpoint, Nye was able to explain the shape of ice sheets and glaciers, to predict the expected pattern of stress and velocity within a glacier, and to derive the advance and retreat of a glacier from the record of accumulation and ablation. These advances have given generations of glaciologists tools to interpret the excellent observational record of glacier behavior and variation. In the 1980s, glaciologist, weaned on these works of Nye and of other similarly adept colleagues, carried their lessons to West Antarctica to study ice streams, the vast conveyor belts of ice that discharged nearly as much Antarctic ice as the much larger East Antarctic ice sheet. Ice streams were a glaciological conundrum. Despite the gently sloping surface, these broad features roared along, moving fastest when the gravitational impetus was least. After two decades of research, ice streams still have not given up all their secrets, yet much is now known. Internal deformation is negligible. Basal friction is frequently nil leaving the shattered margins as the primary means to avoid rapid wastage of the ice sheet. Within the margins, the resistive force results from a delicate balance of heat and evolving ice fabrics. Nevertheless, the bed beneath an ice stream cannot be ignored. It is ultimately the state of the underlying marine sediment that determines whether the ice stream can slide at all. There too, the heat balance is critical with an influx of water required to keep the bed wet enough to let the streams glide along. Ice stream research has been the portal through which glaciologists have seen and identified the complexities of West Antarctic ice sheet dynamics. Remarkably, nearly all time scales seem important. Ice stream

  2. Mars Exploration Rover APXS Results from Matijevic Hill

    NASA Technical Reports Server (NTRS)

    Cohen, B. A.; Clark, B. C.; Gellert, R.; Klingelhoefer, G.; Ming, D. W.; Mittlefehldt, D. W.; Morris, R. V.; Schrader, C. M.; Schroeder, C.; Yen, A. S.; Economou, T.; deSouza, P.; Jolliff, B. L.; Arvidson, R. A.; Squyres, S. W.

    2013-01-01

    Correlation analysis of APXS results on the eastern slope rocks indicate that the Matijevic Hill rocks are overall compositionally distinct from the Shoemaker Formation rocks [6]. Compared to the Shoemaker impactites, Matijevic Hill rocks are higher in Al, Si, and Ni, and lower in Ti, Fe, and Zn. No significant variation is evident in the APXS analyses that indicate the presence of a smectite or other phyllosilicate, as opposed to basaltic rocks. However, APXS data cannot in themselves rule out phyllosilicates. If indeed this material contains smectite, as seen from orbit, it implies that the rock has been isochemically altered to create the phyllosilicate content. The Cl content of the Cape York rocks is relatively high, and whereas the S/Cl ratio in the Burns Formation is 4x higher than in soil, in the Cape York rocks it is lower than in soil. These trends indicate that the alteration processes and types of aqueous salt loads were different between Cape York and Meridiani. In addition, significant deviations from the Martian Mn/Fe ratio are observed in Whitewater Lake coatings and the altered Grasford/Deadwood rocks (Fig. 3). These variations indicate that the redox/pH conditions during alteration of the Shoemaker Formation rocks and the Matijevic Hill rocks were similar, but that the Deadwood/Grasberg unit may have undergone alteration under different conditions, possibly at a later time. The Matijevic Hill outcrops appear to share a common genetic origin. It is not yet clear whether both the Shoemaker impactites and Matijevic Hill rocks are related to the formation of Endeavour Crater, or whether the Matijevic Hill suite represents a prior episode of Martian impact or volcanism. Opportunity continues to investigate both hypotheses.

  3. Sea Ice and Oceanographic Conditions.

    ERIC Educational Resources Information Center

    Oceanus, 1986

    1986-01-01

    The coastal waters of the Beaufort Sea are covered with ice three-fourths of the year. These waters (during winter) are discussed by considering: consolidation of coastal ice; under-ice water; brine circulation; biological energy; life under the ice (including kelp and larger animals); food chains; and ice break-up. (JN)

  4. Producing desired ice faces

    PubMed Central

    Shultz, Mary Jane; Brumberg, Alexandra; Bisson, Patrick J.; Shultz, Ryan

    2015-01-01

    The ability to prepare single-crystal faces has become central to developing and testing models for chemistry at interfaces, spectacularly demonstrated by heterogeneous catalysis and nanoscience. This ability has been hampered for hexagonal ice, Ih––a fundamental hydrogen-bonded surface––due to two characteristics of ice: ice does not readily cleave along a crystal lattice plane and properties of ice grown on a substrate can differ significantly from those of neat ice. This work describes laboratory-based methods both to determine the Ih crystal lattice orientation relative to a surface and to use that orientation to prepare any desired face. The work builds on previous results attaining nearly 100% yield of high-quality, single-crystal boules. With these methods, researchers can prepare authentic, single-crystal ice surfaces for numerous studies including uptake measurements, surface reactivity, and catalytic activity of this ubiquitous, fundamental solid. PMID:26512102

  5. Ice-Nucleating Bacteria

    NASA Astrophysics Data System (ADS)

    Obata, Hitoshi

    Since the discovery of ice-nucleating bacteria in 1974 by Maki et al., a large number of studies on the biological characteristics, ice-nucleating substance, ice nucleation gene and frost damage etc. of the bacteria have been carried out. Ice-nucleating bacteria can cause the freezing of water at relatively warm temperature (-2.3°C). Tween 20 was good substrates for ice-nucleating activity of Pseudomonas fluorescens KUIN-1. Major fatty acids of Isolate (Pseudomonas fluorescens) W-11 grown at 30°C were palmitic, cis-9-hexadecenoic and cis-11-octadecenoic which amounted to 90% of the total fatty acids. Sequence analysis shows that an ice nucleation gene from Pseudomonas fluorescens is related to the gene of Pseudomonas syringae.

  6. Prospecting for Martian Ice

    NASA Technical Reports Server (NTRS)

    McBride, S. A.; Allen, C. C.; Bell, M. S.

    2005-01-01

    During high Martian obliquity, ice is stable to lower latitudes than predicted by models of present conditions and observed by the Gamma Ray Spectrometer (approx. 60 deg N). An ice-rich layer deposited at mid-latitudes could persist to the present day; ablation of the top 1 m of ice leaving a thin insulating cover could account for lack of its detection by GRS. The presence of an ice-layer in the mid-latitudes is suggested by a network of polygons, interpreted as ice-wedge cracks. This study focuses on an exceptional concentration of polygons in Western Utopia (section of Casius quadrangle, roughly 40 deg - 50 deg N, 255 deg - 300 deg W). We attempt to determine the thickness and age of this ice layer through crater-polygons relations.

  7. Subsurface Ice Probe

    NASA Technical Reports Server (NTRS)

    Hecht, Michael; Carsey, Frank

    2005-01-01

    The subsurface ice probe (SIPR) is a proposed apparatus that would bore into ice to depths as great as hundreds of meters by melting the ice and pumping the samples of meltwater to the surface. Originally intended for use in exploration of subsurface ice on Mars and other remote planets, the SIPR could also be used on Earth as an alternative to coring, drilling, and melting apparatuses heretofore used to sample Arctic and Antarctic ice sheets. The SIPR would include an assembly of instrumentation and electronic control equipment at the surface, connected via a tether to a compact assembly of boring, sampling, and sensor equipment in the borehole (see figure). Placing as much equipment as possible at the surface would help to attain primary objectives of minimizing power consumption, sampling with high depth resolution, and unobstructed imaging of the borehole wall. To the degree to which these requirements would be satisfied, the SIPR would offer advantages over the aforementioned ice-probing systems.

  8. Further Insights into the Allan-Herndon-Dudley Syndrome: Clinical and Functional Characterization of a Novel MCT8 Mutation

    PubMed Central

    Yoon, Grace; Visser, Theo J.

    2015-01-01

    Background Mutations in the thyroid hormone (TH) transporter MCT8 have been identified as the cause for Allan-Herndon-Dudley Syndrome (AHDS), characterized by severe psychomotor retardation and altered TH serum levels. Here we report a novel MCT8 mutation identified in 4 generations of one family, and its functional characterization. Methods Proband and family members were screened for 60 genes involved in X-linked cognitive impairment and the MCT8 mutation was confirmed. Functional consequences of MCT8 mutations were studied by analysis of [125I]TH transport in fibroblasts and transiently transfected JEG3 and COS1 cells, and by subcellular localization of the transporter. Results The proband and a male cousin demonstrated clinical findings characteristic of AHDS. Serum analysis showed high T3, low rT3, and normal T4 and TSH levels in the proband. A MCT8 mutation (c.869C>T; p.S290F) was identified in the proband, his cousin, and several female carriers. Functional analysis of the S290F mutant showed decreased TH transport, metabolism and protein expression in the three cell types, whereas the S290A mutation had no effect. Interestingly, both uptake and efflux of T3 and T4 was impaired in fibroblasts of the proband, compared to his healthy brother. However, no effect of the S290F mutation was observed on TH efflux from COS1 and JEG3 cells. Immunocytochemistry showed plasma membrane localization of wild-type MCT8 and the S290A and S290F mutants in JEG3 cells. Conclusions We describe a novel MCT8 mutation (S290F) in 4 generations of a family with Allan-Herndon-Dudley Syndrome. Functional analysis demonstrates loss-of-function of the MCT8 transporter. Furthermore, our results indicate that the function of the S290F mutant is dependent on cell context. Comparison of the S290F and S290A mutants indicates that it is not the loss of Ser but its substitution with Phe, which leads to S290F dysfunction. PMID:26426690

  9. Center Hill Reservoir Fishery Study--Water Level Effects.

    DTIC Science & Technology

    1986-08-01

    The pH and the range of its variations are dependent upon the buffering capacity within a lake . In water containing a bicarbonate in solution, for...WORDS (Continue on reverse aide It noc.esr anidmt ntby block mbi’) Center Hill Lake , TN, Water Levels, Fisheries, Water Quality, Trends. 12A4, C -gvr...water level fluctuation is not a&p~ropriate at Center Hill Lake The graphical analysis of the relationship between the rate of water level change in feet

  10. 2013 strategic petroleum reserve big hill well integrity grading report.

    SciTech Connect

    Lord, David L.; Roberts, Barry L.; Lord, Anna C. Snider; Bettin, Giorgia; Sobolik, Steven Ronald; Park, Byoung Yoon; Rudeen, David Keith; Eldredge, Lisa; Wynn, Karen; Checkai, Dean; Perry, James Thomas

    2014-02-01

    This report summarizes the work performed in developing a framework for the prioritization of cavern access wells for remediation and monitoring at the Big Hill Strategic Petroleum Reserve site. This framework was then applied to all 28 wells at the Big Hill site with each well receiving a grade for remediation and monitoring. Numerous factors affecting well integrity were incorporated into the grading framework including casing survey results, cavern pressure history, results from geomechanical simulations, and site geologic factors. The framework was developed in a way as to be applicable to all four of the Strategic Petroleum Reserve sites.

  11. Analysis of Subsidence Data for the Big Hill Site, Texas

    SciTech Connect

    Bauer, Stephen J.

    1999-06-01

    The elevation change data measured at the Big Hill SPR site over the last 10 years has been studied and a model utilized to project elevation changes into the future. The subsidence rate at Big Hill is low in comparison with other Strategic Petroleum Reserve sites and has decreased with time due to the maintenance of higher operating pressures and the normal decrease in creep closure rate of caverns with time. However, the subsidence at the site is projected to continue. A model was developed to project subsidence values 20 years into the future; no subsidence related issues are apparent from these projections.

  12. NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT ...

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

    NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT EDGE IS THE SINGLE CYLINDER “HOT SHOT” ENGINE THAT PROVIDED POWER FOR THE MILL. JUST IN FRONT OF IT IS AN ARRASTRA. AT CENTER IS THE BALL MILL AND SECONDARY ORE BIN. JUST TO THE RIGHT OF THE BALL MILL IS A RAKE CLASSIFIER, AND TO THE RIGHT ARE THE CONCENTRATION TABLES. WARM SPRINGS CAMP IS IN THE DISTANCE. SEE CA-292-17 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  13. NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT ...

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

    NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT EDGE IS THE SINGLE CYLINDER “HOT SHOT” ENGINE THAT PROVIDED POWER FOR THE MILL. JUST IN FRONT OF IT IS AN ARRASTRA. AT CENTER IS THE BALL MILL AND SECONDARY ORE BIN. JUST TO THE RIGHT OF THE BALL MILL IS A RAKE CLASSIFIER, AND TO THE RIGHT ARE THE CONCENTRATION TABLES. WARM SPRINGS CAMP IS IN THE DISTANCE. SEE CA-292-4 FOR IDENTICAL B&W NEGATIVE. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  14. Ice barrier construction

    SciTech Connect

    Finucane, R. G.; Jahns, H. O.

    1985-06-18

    A method is provided for constructing spray ice barriers to protect offshore structures in a frigid body of water from mobile ice, waves and currents. Water is withdrawn from the body of water and is sprayed through ambient air which is below the freezing temperature of the water so that a substantial amount of the water freezes as it passes through the air. The sprayed water is directed to build up a mass of ice having a size and shape adapted to protect the offshore structure. Spray ice barriers can also be constructed for the containment of pollutant spills.

  15. An ice lithography instrument.

    PubMed

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J A

    2011-06-01

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines.

  16. An ice lithography instrument

    SciTech Connect

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J. A.

    2011-06-15

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines.

  17. Ice age paleotopography

    SciTech Connect

    Peltier, W.R. )

    1994-07-08

    A gravitationally self-consistent theory of postglacial relative sea level change is used to infer the variation of surface ice and water cover since the Last Glacial Maximum (LGM). The results show that LGM ice volume was approximately 35 percent lower than suggested by the CLIMAP reconstruction and the maximum heights of the main Laurentian and Fennoscandian ice complexes are inferred to have been commensurately lower with respect to sea level. Use of these Ice Age boundary conditions in atmospheric general circulation models will yield climates that differ significantly from those previously inferred on the basis of the CLIMAP data set.

  18. Reconstructed Paleo-topography of the Columbia Hills, Mars

    NASA Astrophysics Data System (ADS)

    Cole, S. B.; Watters, W. A.; Aron, F.; Squyres, S. W.

    2013-12-01

    From June 2004 through March 2010, the Mars Exploration Rover Spirit conducted a detailed campaign examining the Columbia Hills of Gusev Crater. In addition to mineralogical and chemical investigations, Spirit's stereo panoramic (Pancam) and navigation (Navcam) cameras obtained over 7,000 images of geologic targets along the West Spur of the Columbia Hills and Husband Hill, the highest peak. We have analyzed the entirety of this dataset, which includes stereo coverage of several outcrop exposures with apparent bedding. We have measured the bedding plane orientations of hundreds of fine-scale (~1-100cm) features on all of the potentially in-place outcrops using Digital Terrain Models (DTMs) derived from the rover's Pancam stereo image data, and mapped these orientations on a regional HiRISE image and DTM. Assuming that the bedding material was deposited conformably on the topography at the time of emplacement, we reconstruct the paleo-topography of the Columbia Hills. Our reconstructed paleo-topography is similar to the modern shape of Husband Hill, but with steeper slopes, consistent with a substantial amount of erosion since deposition. The Columbia Hills are an irregular, nearly-triangular edifice of uncertain origin, situated near the center of the 160km-diameter crater and hypothesized to be either the remnant of a central peak structure, or overlapping crater rims. They span ~6.6 km in the northerly direction by ~3.6 km in the easterly direction, and rise 90m above the basaltic plains that fill the floor of Gusev Crater and embay the Hills. The topography is as irregular as the perimeter, and is cut by numerous valleys of varying lengths, widths, and directional trends. Along the traverse, Spirit examined several rock classes as defined by elemental abundances from the Alpha Particle X-ray Spectrometer (APXS) and identified remotely by the Miniature Thermal Emission Spectrometer (Mini-TES). Unlike the Gusev Plains, the rocks of the Columbia Hills show

  19. Arctic Sea Ice Maximum 2011

    NASA Video Gallery

    AMSR-E Arctic Sea Ice: September 2010 to March 2011: Scientists tracking the annual maximum extent of Arctic sea ice said that 2011 was among the lowest ice extents measured since satellites began ...

  20. Bacterial ice crystal controlling proteins.

    PubMed

    Lorv, Janet S H; Rose, David R; Glick, Bernard R

    2014-01-01

    Across the world, many ice active bacteria utilize ice crystal controlling proteins for aid in freezing tolerance at subzero temperatures. Ice crystal controlling proteins include both antifreeze and ice nucleation proteins. Antifreeze proteins minimize freezing damage by inhibiting growth of large ice crystals, while ice nucleation proteins induce formation of embryonic ice crystals. Although both protein classes have differing functions, these proteins use the same ice binding mechanisms. Rather than direct binding, it is probable that these protein classes create an ice surface prior to ice crystal surface adsorption. Function is differentiated by molecular size of the protein. This paper reviews the similar and different aspects of bacterial antifreeze and ice nucleation proteins, the role of these proteins in freezing tolerance, prevalence of these proteins in psychrophiles, and current mechanisms of protein-ice interactions.

  1. Bacterial Ice Crystal Controlling Proteins

    PubMed Central

    Lorv, Janet S. H.; Rose, David R.; Glick, Bernard R.

    2014-01-01

    Across the world, many ice active bacteria utilize ice crystal controlling proteins for aid in freezing tolerance at subzero temperatures. Ice crystal controlling proteins include both antifreeze and ice nucleation proteins. Antifreeze proteins minimize freezing damage by inhibiting growth of large ice crystals, while ice nucleation proteins induce formation of embryonic ice crystals. Although both protein classes have differing functions, these proteins use the same ice binding mechanisms. Rather than direct binding, it is probable that these protein classes create an ice surface prior to ice crystal surface adsorption. Function is differentiated by molecular size of the protein. This paper reviews the similar and different aspects of bacterial antifreeze and ice nucleation proteins, the role of these proteins in freezing tolerance, prevalence of these proteins in psychrophiles, and current mechanisms of protein-ice interactions. PMID:24579057

  2. Small Airframe Manufacturer's Icing Perspective

    NASA Technical Reports Server (NTRS)

    Hoppins, Jim

    2009-01-01

    This viewgraph presentation describes the icing effects, risk mitigation practices, and icing certifications for various Cessna small aircraft models. NASA's role in the development of simulation tools for icing certifications is also discussed.

  3. Ice-on-ice impact experiments.

    NASA Astrophysics Data System (ADS)

    Kato, Manabu; Iijima, Yu-Ichi; Arakawa, Masahiko; Okimura, Yasuyuki; Fujimura, Akio; Maeno, Norikazu; Mizutani, Hitoshi

    1995-02-01

    Impact experiments, cratering and fragmentation, on water ice were performed in order to test the scaling laws previously constructed on rocks and sands for studying the collision process in the planetary history. The installation of a vertical gas gun in a cold room at -18°C (255 K) made it possible to use a projectile of water ice and to get the detailed mass distribution of ice fragments. Experimental results indicated the necessity for large modification of those scaling laws. Material dependence was investigated by using projectiles of ice, aluminum, and polycarbonate. Differences were observed in the morphology and efficiencies of cratering and in the energies required to initiate the fragmentation. Moreover, an abrupt increase of cratering efficiency, suggesting a change of excavation mechanism, was found at a critical diameter of spalled crater. The mass (size) distribution of small ice fragments obeyed a power law with an exponent significantly larger than that in rocks. The exponent was the same as that in Saturn's ring particles estimated from the data by the microwave occultation, which indicates a collisional disruption ring origin.

  4. 1. Historic American Buildings Survey Joseph Hill, Photographer August 10th, ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer August 10th, 1936 (Copied from small photo taken by survey members) OLD APARTMENT HOUSE - Jansonist Colony, Old Apartment House, Main Street, Bishop Hill, Henry County, IL

  5. GHG PSD Permit: Cheyenne Light, Fuel & Power / Black Hills Power, Inc. – Cheyenne Prairie Generating Station

    EPA Pesticide Factsheets

    This page contains the final PSD permit for the Cheyenne Light, Fuel & Power / Black Hills Power, Inc. Cheyenne Prairie Generating Station, located in Laramie, Wyoming, and operated by Black Hills Service Company.

  6. [Tail Plane Icing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Aviation Safety Program initiated by NASA in 1997 has put greater emphasis in safety related research activities. Ice-contaminated-tailplane stall (ICTS) has been identified by the NASA Lewis Icing Technology Branch as an important activity for aircraft safety related research. The ICTS phenomenon is characterized as a sudden, often uncontrollable aircraft nose- down pitching moment, which occurs due to increased angle-of-attack of the horizontal tailplane resulting in tailplane stall. Typically, this phenomenon occurs when lowering the flaps during final approach while operating in or recently departing from icing conditions. Ice formation on the tailplane leading edge can reduce tailplane angle-of-attack range and cause flow separation resulting in a significant reduction or complete loss of aircraft pitch control. In 1993, the Federal Aviation Authority (FAA) and NASA embarked upon a four-year research program to address the problem of tailplane stall and to quantify the effect of tailplane ice accretion on aircraft performance and handling characteristics. The goals of this program, which was completed in March 1998, were to collect aerodynamic data for an aircraft tail with and without ice contamination and to develop analytical methods for predicting the effects of tailplane ice contamination. Extensive dry air and icing tunnel tests which resulted in a database of the aerodynamic effects associated with tailplane ice contamination. Although the FAA/NASA tailplane icing program generated some answers regarding ice-contaminated-tailplane stall (ICTS) phenomena, NASA researchers have found many open questions that warrant further investigation into ICTS. In addition, several aircraft manufacturers have expressed interest in a second research program to expand the database to other tail configurations and to develop experimental and computational methodologies for evaluating the ICTS phenomenon. In 1998, the icing branch at NASA Lewis initiated a second

  7. Allan Brooks, naturalist and artist (1869-1946): the travails of an early twentieth century wildlife illustrator in North America.

    PubMed

    Winearls, Joan

    2008-01-01

    British by birth Allan Cyril Brooks (1869-1946) emigrated to Canada in the 1880s, and became one of the most important North American bird illustrators during the first half of the twentieth century. Brooks was one of the leading ornithologists and wildlife collectors of the time; he corresponded extensively with other ornithologists and supplied specimens to many major North American museums. From the 1890s on he hoped to support himself by painting birds and mammals, but this was not possible in Canada at that time and he was forced to turn to American sources for illustration commissions. His work can be compared with that of his contemporary, the leading American bird painter Louis Agassiz Fuertes (1874-1927), and there are striking similarities and differences in their careers. This paper discusses the work of a talented, self-taught wildlife artist working in a North American milieu, his difficulties and successes in a newly developing field, and his quest for Canadian recognition.

  8. Commercial aviation icing research requirements

    NASA Technical Reports Server (NTRS)

    Koegeboehn, L. P.

    1981-01-01

    A short range and long range icing research program was proposed. A survey was made to various industry and goverment agencies to obtain their views of needs for commercial aviation ice protection. Through these responsed, other additional data, and Douglas Aircraft icing expertise; an assessment of the state-of-the-art of aircraft icing data and ice protection systems was made. The information was then used to formulate the icing research programs.

  9. Ancient granite gneiss in the Black Hills, South Dakota

    USGS Publications Warehouse

    Zartman, R.E.; Norton, J.J.; Stern, T.W.

    1964-01-01

    Granite gneiss, with an age of approximately 2.5 billion years, in the Black Hills, South Dakota , provides a link betweeen ancient rocks in western Wyoming and Montana and in eastern North and South Dakota and Minnesota. The discovery suggests that early Precambrian rocks covered an extensive area in northcentral United States and were not restricted to several small nuclei.

  10. Lost Hills Field Trial - incorporating new technology for resevoir management

    NASA Technical Reports Server (NTRS)

    Fielding, E. J.; Brink, J. L.; Patzek, T. W.; Silin, D. B.

    2002-01-01

    This paper will discuss how Chevron U.S.A. Production Company is implementing a field trial that will use Supervisory Control and Data Acquisition (SCADA)on injection wells, in conjunction with satellite images to measure ground elevation changes, to perform real-time resevoir management in the Lost Hills Field.

  11. 1. Historic American Buildings Survey Joseph Hill's Photograph Copy of ...

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

    1. Historic American Buildings Survey Joseph Hill's Photograph Copy of Original Photograph May5, 1936 SOUTH ELEVATION 1352 W.WASHINGTON BLVD. -1362 CHICAGO, ILLINOIS. - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  12. Ten Tips for Higher Education Leaders: The Capitol Hill Perspective.

    ERIC Educational Resources Information Center

    Ford, William D.

    1990-01-01

    Suggestions to college administrators include realize that the essential lubricant of politics on Capitol Hill is relations of trust, confidence, and familiarity; bring solutions as well as problems to legislators; talk to members on the committee handling the issue of concern; help friends get reelected. (MLW)

  13. CH2M Hill cleared in tunnel explosion case

    SciTech Connect

    Krizan, W.G.; Bradford, H.; Schriener, J.

    1993-09-06

    One of the most critical issues in industry is whether architects and engineers should be held responsible for construction safety on jobsites. The Occupational Safety and Health Administration says yes under certain conditions. But the Occupational Safety and Health Review Commission has overturned one application of that view on appeal in a controversial case. It involves a unit of Denver-based CH2M Hill Cos.'s role as program manager for the Milwaukee Metropolitan Sewerage District (MMSD) on its $2.2-billion water pollution abatement program. On May 5, 1989, OSHA cited CH2M Hill Central Inc. for 46 willful safety violations in connection with a 1988 methane tunnel explosion that killed three supervisors of contractor S.A. Healy Co., Chicago, Healy was charged with 68 violations. Healy encountered methane while boring CT-7, a two-mile crosstown tunnel. It evacuated the site, but didn't follow the evacuation plan. It failed to shut down all nonessential equipment and the supervisors returned after waiting only 17 minutes instead of the one hour minimum. CH2M Hill's citations and proposed $460,000 fine for violating OSHA's construction standards were for having 45 pieces of unapproved electrical equipment in the tunnel and improper ventilation equipment. CH2M Hill claimed the standards did not apply to it because the firm did not engage in construction work, exercise substantial supervision over the construction work performed by the contractor or create or control the hazardous condition.

  14. Mineralogy of the Pahrump Hills Region, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Rampe, E. B.; Ming, D. W.; Vaniman, D. T.; Blake, D. F.; Chipera, S. J.; Morris, R. V.; Bish, D. L.; Cavanagh, P. D.; Achilles, C. N.; Bristow, T. F.; Morrison, S. M.; Treiman, A. H.; Downs, R. T.; Farmer, J. D.; Crisp, J. A.; Fendrich, K.; Morookian, J. M.

    2015-01-01

    The Pahrump Hills region of Gale crater is a approximately 12 millimeter thick section of sedimentary rocks in the Murray formation, interpreted as the basal geological unit of Mount Sharp. The Mars Science Laboratory, Curiosity, arrived at the Pahrump Hills in September, 2014, and performed a detailed six-month investigation of the sedimentary structures, geochemistry, and mineralogy of the area. During the campaign, Curiosity drilled and delivered three rock samples to its internal instruments, including the CheMin XRD/XRF. The three targets, Confidence Hills, Mojave 2, and Telegraph Peak, contain variable amounts of plagioclase, pyroxene, iron oxides, jarosite, phyllosilicates, and X-ray amorphous material. Hematite was predicted at the base of Mount Sharp from orbital visible/near-IR spectroscopy, and CheMin confirmed this detection. The presence of jarosite throughout Pahrump Hills suggests the sediments experienced acid-sulfate alteration, either in-situ or within the source region of the sediments. This acidic leaching environment is in stark contrast to the environment preserved within the Sheepbed mudstone on the plains of Gale crater. The minerals within Sheepbed, including Fe-saponite, indicate these sediments were deposited in a shallow lake with circumneutral pH that may have been habitable.

  15. Hills for the Head. Art across the Curriculum.

    ERIC Educational Resources Information Center

    Sartorius, Tara Cady

    2000-01-01

    Provides information on Maltby Sykes, the painter, addressing issues such as his assignment during World War II, being an apprentice to Diego Rivera, and his relationship with George C. Miller. Discusses both the painting and the sketch titled "Hills." Includes activities in geography, visual art, history, and mathematics. (CMK)

  16. Dynamics of liquefaction during the 1987 superstition hills, california, earthquake.

    PubMed

    Holzer, T L; Hanks, T C; Youd, T L

    1989-04-07

    Simultaneous measurements of seismically induced pore-water pressure changes and surface and subsurface accelerations at a site undergoing liquefaction caused by the Superstition Hills, California, earthquake (24 November 1987; M = 6.6) reveal that total pore pressures approached lithostatic conditions, but, unexpectedly, after most of the strong motion ceased. Excess pore pressures were generated once horizontal acceleration exceeded a threshold value.

  17. The Lawn Hill Impact Structure: A Unique Terrestrial Crater?

    NASA Astrophysics Data System (ADS)

    Darlington, V. J.; Blenkinsop, T. G.; Orchiston, W.; Tomkins, A.

    2012-09-01

    The Lawn Hill Impact Structure (LHIS) is located 250 km North of Mt Isa in Queensland. The structure consists of a central area ca. 8 km diameter enclosed by a ca. 5 km annulus of Cambrian limestone, a unique structure for terrestrial impacts.

  18. 112. Dennis Hill, Photographer January 1998 VIEW OF SAN FRANCISCO ...

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

    112. Dennis Hill, Photographer January 1998 VIEW OF SAN FRANCISCO VIADUCT (RIGHT), UPPER DECK OFF-RAMP (LEFT), AND LOWER DECK ON-RAMP FROM TRANSBAY TERMINAL BUS LOOP, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  19. 121. Dennis Hill, Photographer April 1998 ELEVATION VIEW OF UPPER ...

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

    121. Dennis Hill, Photographer April 1998 ELEVATION VIEW OF UPPER DECK OFF-RAMP AND TRANSBAY TERMINAL BUS LOOP, CROSSING OVER FOLSOM STREET AT RIGHT, FACING SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  20. 114. Dennis Hill, Photographer April 1998 VIEW OF UPPER DECK ...

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

    114. Dennis Hill, Photographer April 1998 VIEW OF UPPER DECK OFF-RAMP AND LOWER DECK ON-RAMP FROM TRANSBAY TERMINAL BUS LOOP, WITH SAN FRANCISCO VIADUCT IN BACKGROUND AT RIGHT, FACING EAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  1. 113. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK ...

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

    113. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK OFF-RAMP WITH LOWER DECK ON-RAMP FROM TRANSBAY TERMINAL BUS LOOP IN FOREGROUND, FACING WEST-NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  2. 77 FR 17402 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-26

    ..., Black Hills National Forest, in the wake of increasingly severe and intense wild fires and mountain pine... forest issues such as forest plan revisions or amendments, forest health including fire management and... Plan, a priority following the major fires including the 86,000 acre Jasper Fire in 2000; 2. A...

  3. 77 FR 8214 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... increasingly severe and intense wild fires and mountain pine beetle epidemics. The purpose of the Board is to... forest issues such as forest plan revisions or amendments, forest health including fire management and... 2004 report on the Black Hills Fuels Reduction Plan, a priority following the major fires including...

  4. 17. MERRITT PARKWAY UNDER SPORT HILL ROAD, GRADE SEPARATION. Photocopy ...

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

    17. MERRITT PARKWAY UNDER SPORT HILL ROAD, GRADE SEPARATION. Photocopy of drawing (original in Connecticut Department of Transportation, Wethersfield); Connecticut State Highway Department, Approved February 1936. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  5. Possible Late Quaternary faulting in the Benton Hills, southeastern Missouri

    SciTech Connect

    Palmer, J.R.; Hoffman, D. . Dept. of Natural Resources)

    1993-03-01

    Geologic mapping in the 1930's by Dan Stewart and Lyle McManamy identified numerous faults in the Thebes Gap area of the Benton Hills, including two post-late Quaternary faults (max. of 10 m displacement) along the southeastern escarpment. Recent geologic mapping (Richard Harrison, pers. comm.) suggests dextral strike-slip displacement on most of these faults; some deformation post-dates the Pliocene-Pleistocene Mounds gravel. Small historical earthquake epicenters have been recorded in the Benton Hills area. Review of these data and analysis of the geologic and structural relationships to small- and large-scale drainage and alluvial features suggest tectonic control of the southeastern escarpment of the Benton Hills. The authors propose the coincidence of geologic structures and landforms resembles tectonically active alluvial basin margins, with the Benton Hills southeastern margin representing a fault block uplift escarpment. Future seismic reflection, drilling and trenching studies are planned to determine if the escarpment is fault controlled and of recent origin.

  6. Adjusting the Focus: Padua Hills Theatre and Latino History.

    ERIC Educational Resources Information Center

    Garcia, Matt

    1996-01-01

    Reveals an interesting and overlooked chapter in Hispanic cultural history. The Claremont, California, Padua Hills Theater presented Spanish-language, Mexican-theme musicals to a mostly white audience from 1931 to 1974. Although it presented romantic, and occasionally stereotypical views of Mexican American life, the theater deserves recognition.…

  7. SummerHill Homes, San Francisco Bay Area, Fremont, California

    SciTech Connect

    2006-10-01

    Building America fact sheet on SummerHill Homes of Northern California. The Villa Savona Homes in Fremont, California were built using 15% fly ash in concrete, engineered lumber for floors, high efficiency windows with Low-emissivity (Low-E) glass, and fi

  8. SMITH FARM FROM CEMETERY HILL, LOOKING SOUTHWEST. (This image shows ...

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

    SMITH FARM FROM CEMETERY HILL, LOOKING SOUTHWEST. (This image shows the Smith Farm in the center of Ebey’s Prairie. Ebey’s Landing and the Puget Sound can be seen on the right. Farmers from the Sherman-Bishop Dairy are visible at the bottom left, cutting hay.) - Smith Farm, 399 Ebey Road, Coupeville, Island County, WA

  9. Project Hill-Climb: Drafting and Design in Motion

    ERIC Educational Resources Information Center

    Crowl, William F.

    2008-01-01

    This article describes the Hill-Climb project of a second level Computer-Aided Drafting and Design (CADD) class. The author primarily designed the activity to increase student understanding of the assembly drawing process and its components. The emphasis on problem solving adds a dimension that can aid students in their other classes as well. By…

  10. Blue Hills Regional Grad Fulfills Dream, Becomes Astronaut

    ERIC Educational Resources Information Center

    Bass, Judy

    2012-01-01

    This article features Scott D. Tingle, a former career and technical education (CTE) student who always aimed high. November 4, 2011 marked the official culmination of a cherished, virtually lifelong dream of his--becoming an astronaut. It was a goal he had in mind even when he was a high school student in the 1980s at Blue Hills Regional…

  11. Geology of the Limestone Hills, Broadwater County, Montana

    USGS Publications Warehouse

    Ruppel, Edward Thompson

    1950-01-01

    The Limestone Hills, a natural topographic unit having an area of about 16 square miles, are situated a few miles west and southwest of Townsend, Broadwater County, Montana. They are composed of pre-Cambrian, Paleozoic, and Mesozoic sedimentary rocks i

  12. 15. MERRITT PARKWAY UNDER SPORT HILL ROAD, FRAME AND WING ...

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

    15. MERRITT PARKWAY UNDER SPORT HILL ROAD, FRAME AND WING WALL DETAILS. Photocopy of drawing (original in Connecticut Department of Transportation, Wethersfield); Connecticut State Highway Department, Approved February 1936. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  13. 13. MERRITT PARKWAY UNDER SPORT HILL ROAD, GENERAL PLAN. Photocopy ...

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

    13. MERRITT PARKWAY UNDER SPORT HILL ROAD, GENERAL PLAN. Photocopy of drawing (original in Connecticut Department of Transportation, Wethersfield); Connecticut State Highway Department, Approved February 1936. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  14. 14. MERRITT PARKWAY UNDER SPORT HILL ROAD, FOOTING PLAN AND ...

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

    14. MERRITT PARKWAY UNDER SPORT HILL ROAD, FOOTING PLAN AND LEG DETAILS. Photocopy of drawing (original in Connecticut Department of Transportation, Wethersfield); Connecticut State Highway Department, Approved February 1936. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  15. 16. MERRITT PARKWAY UNDER SPORT HILL ROAD, RAILING AND PYLON ...

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

    16. MERRITT PARKWAY UNDER SPORT HILL ROAD, RAILING AND PYLON DETAILS. Photocopy of drawing (original in Connecticut Department of Transportation, Wethersfield); Connecticut State Highway Department, Approved February 1936. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  16. 1. Historic American Buildings Survey Joseph Hill, Photographer March 10, ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer March 10, 1936 CAST IRON BALCONY RAIL AND WROUGHT IRON WINDOW RAILING 945 NORTH DEARBORN STREET, CHICAGO - Chicago Ironwork, Judge Carpenter House (Cast Iron Balcony Railing), 945 North Dearborn Street, Chicago, Cook County, IL

  17. Rock Hill Business, Education, and Community Online Network.

    ERIC Educational Resources Information Center

    Broyles, Alan

    The Business, Education & Community On-line Network (BEACON) is designed to support development and implementation of demonstration applications operating in an asynchronous transfer mode (ATM) fiber optic network environment. Initial origination and destination sites include high schools and universities around Rock Hill (South Carolina). The…

  18. FOLKLORE REMEDIES FOR DANDRUFF FROM TIRUMALA HILLS OF ANDHRA PRADESH

    PubMed Central

    Balaji Rao, N.S; Rajasekhar, D.; Raju, D. Chengal

    1996-01-01

    The report gives an account of the use of 25 plant species by local herbalists of tirumala hills, chittoor district of Andhra Pradesh for dandruff (seborheic). The paper discusses the methods of preparation and dose of administration of curde drugs as suggested by them. PMID:22556761

  19. Environmental Assessment: Proposed Consolidated Warehouse, Hill Air Force Base, Utah

    DTIC Science & Technology

    2011-02-01

    Utah FA8201-09-D-0006 Klein, Randal Johnson, Sam Streamline Consulting, LLC 1713 N. Sweetwater Lane Farmington, Utah 84025 Hill Air Force Base 7274... Air Force Base (AFB) proposes to adequate warehouse facilities in which to store equipment for worldwide United States Air Force (USAF) operations

  20. 222. Dennis Hill, Photographer April 1998 VIEW OF YERBA BUENA ...

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

    222. Dennis Hill, Photographer April 1998 VIEW OF YERBA BUENA LOWER DECK OFF-RAMP WITH UPPER DECK ON-RAMP AND WEST PORTAL IN BACKGROUND, FACING EAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  1. Using the Hill Cipher to Teach Cryptographic Principles

    ERIC Educational Resources Information Center

    McAndrew, Alasdair

    2008-01-01

    The Hill cipher is the simplest example of a "block cipher," which takes a block of plaintext as input, and returns a block of ciphertext as output. Although it is insecure by modern standards, its simplicity means that it is well suited for the teaching of such concepts as encryption modes, and properties of cryptographic hash functions. Although…

  2. EDIBLE FRUIT YIELDING PLANTS OF SHEVAROY HILLS IN TAMIL NADU

    PubMed Central

    Alagesaboopathi, C.; Balu, S.; Dwarakan, P.

    1996-01-01

    The paper deals with the common edible fruit yielding plants, During the course of medicinal plant survey of shevaroy hills of Eastern ghats. Salem district, Tamil Nadu. Thirty species belonging to 23 genera and 21 families yield edible fruits. They are listed in alphabetical order followed by family, common name and Tamil names. PMID:22556784

  3. 27. Photocopy of engineering drawing by Leeds, Hill, Barnard, and ...

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

    27. Photocopy of engineering drawing by Leeds, Hill, Barnard, and Jewitt, Architect-Engineer (original drawing located at County of San Luis Obispo). STRUT LAYOUT -- RIGHT ABUTMENT. - Salinas Dam, Salinas River near Pozo Road, Santa Margarita, San Luis Obispo County, CA

  4. 26. Photocopy of engineering drawing by Leeds, Hill, Barnard, and ...

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

    26. Photocopy of engineering drawing by Leeds, Hill, Barnard, and Jewitt, Architect-Engineer (original drawing located at County of San Luis Obispo) SALINAS DAM ROOFING PLAN. - Salinas Dam, Salinas River near Pozo Road, Santa Margarita, San Luis Obispo County, CA

  5. 25. Photocopy of engineering drawing by Leeds, Hill, Barnard, and ...

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

    25. Photocopy of engineering drawing by Leeds, Hill, Barnard, and Jewitt, Architect-Engineer (original drawing located at County of San Luis Obispo). SALINAS DAM PLAN AND SECTIONS. - Salinas Dam, Salinas River near Pozo Road, Santa Margarita, San Luis Obispo County, CA

  6. Overview of LIMEX'87 ice observations

    NASA Technical Reports Server (NTRS)

    Carsey, Frank D.; Holt, Benjamin; Argus, Susan A. Digby; Collins, Michael J.; Livingstone, Charles E.

    1989-01-01

    Ice observations, results, and conclusions are summarized for the March 1987 Labrador Ice Margin Experiment (LIMEX'87), an international oceanographic study conducted in the pack ice of the Grand Banks area off the coast of Newfoundland. Included are the ice extent, floe size and thickness, ice kinematics and rheology, ice microwave properties, oceanic properties under the ice, and penetration of swell into the ice.

  7. Spectroscopic signature for ferroelectric ice

    NASA Astrophysics Data System (ADS)

    Wójcik, Marek J.; Gług, Maciej; Boczar, Marek; Boda, Łukasz

    2014-09-01

    Various forms of ice exist within our galaxy. Particularly intriguing type of ice - ‘ferroelectric ice' was discovered experimentally and is stable in temperatures below 72 K. This form of ice can generate enormous electric fields and can play an important role in planetary formation. In this letter we present Car-Parrinello simulation of infrared spectra of ferroelectric ice and compare them with spectra of hexagonal ice. Librational region of the spectra can be treated as spectroscopic signature of ice XI and can be of help to identify ferroelectric ice in the Universe.

  8. Artic ice and drilling structures

    SciTech Connect

    Sodhl, D.S.

    1985-04-01

    The sea ice in the southern Beaufort Sea is examined and subdivided into three zones: the fast ice zone, the seasonal pack-ice zone, an the polar pack ice zone. Each zone requires its own type of system. Existing floating drilling systems include ice-strengthened drill ships, conical drilling systems, and floating ice platforms in deep-water land-fast ice. The development of hydrocarbon resources in the Arctic presents great challenges to engineers, since the structures are required to operate safely under various conditions. Significant progress has yet to be made in understanding the behavior of ice.

  9. Making an Ice Core.

    ERIC Educational Resources Information Center

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  10. Rheology of glacier ice

    NASA Technical Reports Server (NTRS)

    Jezek, K. C.; Alley, R. B.; Thomas, R. H.

    1985-01-01

    A new method for calculating the stress field in bounded ice shelves is used to compare strain rate and deviatoric stress on the Ross Ice Shelf, Antarctica. The analysis shows that strain rate (per second) increases as the third power of deviatoric stress (in newtons/sq meter), with a constant of proportionality equal to 2.3 x 10 to the -25th.

  11. Ice Core Investigations

    ERIC Educational Resources Information Center

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  12. Academic Airframe Icing Perspective

    NASA Technical Reports Server (NTRS)

    Bragg, Mike; Rothmayer, Alric; Thompson, David

    2009-01-01

    2-D ice accretion and aerodynamics reasonably well understood for engineering applications To significantly improve our current capabilities we need to understand 3-D: a) Important ice accretion physics and modeling not well understood in 3-D; and b) Aerodynamics unsteady and 3-D especially near stall. Larger systems issues important and require multidisciplinary team approach

  13. Snow and Ice.

    ERIC Educational Resources Information Center

    Minneapolis Independent School District 275, Minn.

    This experimental edition provides a number of activities useful for investigating snow and ice with elementary school children. Commencing with games with ice cubes, the activities lead through studies of snowflakes, snowdrifts, effects of wind and obstacles on the shape and formation of drifts, to a study of animals living under snow. The…

  14. Fire beneath the ice

    SciTech Connect

    Monastersky, R.

    1993-02-13

    A volcano discovered six years ago by researchers Blankenship and Bell under Antarctica poses questions about a potential climatic catastrophe. The researchers claim that the volcano is still active, erupting occasionally and growing. A circular depression on the surface of the ice sheet has ice flowing into it and is used to provide a portrait of the heat source. The volcano is on a critical transition zone within West Antarctica with fast flowing ice streams directly downhill. Work by Blankenship shows that a soft layer of water-logged sediments called till provide the lubricating layer on the underside of the ice streams. Volcanos may provide the source of this till. The ice streams buffer the thick interior ice from the ocean and no one know what will happen if the ice streams continue to shorten. These researchers believe their results indicate that the stability of West Antarctica ultimately depends less on the current climate than on the location of heat and sediments under the ice and the legacy of past climatic changes.

  15. Larsen B Ice Shelf

    Atmospheric Science Data Center

    2013-04-16

    ... ice shelf and the rough crevasses of glaciers appear orange. In contrast to the spectral composite, which provides information on ... surfaces appear brighter on their illuminated faces, the orange color in the multi-angle composite suggests a macroscopically rough ice ...

  16. Turning into Ice

    ERIC Educational Resources Information Center

    Pietsch, Renée B.; Hanlon, Regina; Bohland, Cynthia; Schmale, David G., III

    2016-01-01

    This article describes an interdisciplinary unit in which students explore biological "ice nucleation"--by particles that cause water to freeze at temperatures above -38°C--through the lens of the microbial ice nucleator "Pseudomonas syringae." Such This activity, which aligns with the "Next Generation Science…

  17. 76 FR 28766 - Flint Hills Resources Alaska, LLC; Notice of Petition for Declaratory Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... Energy Regulatory Commission Flint Hills Resources Alaska, LLC; Notice of Petition for Declaratory Order... Procedure of the Federal Energy Regulatory Commission (18 CFR 385.207(a)(2)(2010)), Flint Hills Resources Alaska, LLC (Flint Hills) filed a petition for an order declaring that an as- yet unfiled,...

  18. Teachers Guide to the Shakers at Pleasant Hill. A Resource Unit for Elementary Teachers. Intermediate Level.

    ERIC Educational Resources Information Center

    Shakertown at Pleasant Hill, Kentucky, Inc., Harrodsburg.

    The guide provides activities for use with children in grades four through six before and after a field trip to Shakertown at Pleasant Hill. Established as a Shaker community in 1805, Pleasant Hill now has 27 buildings restored and open for public use. The study of Pleasant Hill can be used as an example of rural or village life in nineteenth…

  19. 75 FR 63465 - Hill-Lake Gas Storage, LLC; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... Energy Regulatory Commission Hill-Lake Gas Storage, LLC; Notice of Filing October 7, 2010. Take notice that on September 30, 2010, Hill-Lake Gas Storage, LLC (Hill-Lake) filed a revised Statement of Operating Conditions (SOC) for its Storage Services, proposing substantive revisions to its tariff...

  20. 78 FR 48466 - Comcast Cable, West Division Customer Care, Morgan Hill, California; Notice of Negative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-08

    ... Employment and Training Administration Comcast Cable, West Division Customer Care, Morgan Hill, California... workers of Comcast Cable, West Division Customer Care, Morgan Hill, California (subject firm). The... eligibility of Comcast Cable, West Division Customer Care, Morgan Hill, California, to apply for...