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Sample records for haiged mandlid minema

  1. Meltwater runoff from Haig Glacier, Canadian Rocky Mountains, 2002-2013

    NASA Astrophysics Data System (ADS)

    Marshall, S. J.

    2014-07-01

    Observations of high-elevation meteorological conditions, glacier mass balance, and glacier runoff are sparse in western Canada and the Canadian Rocky Mountains, leading to uncertainty about the importance of glaciers to regional water resources. This needs to be quantified so that the impacts of ongoing glacier recession can be evaluated with respect to alpine ecology, hydroelectric operations, and water resource management. I assess the seasonal evolution of glacier runoff in an alpine watershed on the continental divide in the Canadian Rocky Mountains. Analysis is based on meteorological, snowpack and surface energy balance data collected at Haig Glacier from 2002-2013. The study area is one of several glacierized headwaters catchments of the Bow River, which flows eastward to provide an important supply of water to the Canadian prairies. Annual specific discharge from snow- and ice-melt on Haig Glacier averaged 2350 mm water equivalent (w.e.) from 2002-2013, with 42% of the runoff derived from melting of glacier ice and firn, i.e. water stored in the glacier reservoir. This is an order of magnitude greater than the annual specific discharge from non-glacierized parts of the Bow River basin. From 2002-2013, meltwater derived from the glacier storage was equivalent to 5-6% of the flow of the Bow River in Calgary in late summer and 2-3% of annual discharge. The basin is typical of most glacier-fed mountains rivers, where the modest and declining extent of glacierized area in the catchment limits the glacier contribution to annual runoff.

  2. Meltwater run-off from Haig Glacier, Canadian Rocky Mountains, 2002-2013

    NASA Astrophysics Data System (ADS)

    Marshall, S. J.

    2014-12-01

    Observations of high-elevation meteorological conditions, glacier mass balance, and glacier run-off are sparse in western Canada and the Canadian Rocky Mountains, leading to uncertainty about the importance of glaciers to regional water resources. This needs to be quantified so that the impacts of ongoing glacier recession can be evaluated with respect to alpine ecology, hydroelectric operations, and water resource management. In this manuscript the seasonal evolution of glacier run-off is assessed for an alpine watershed on the continental divide in the Canadian Rocky Mountains. The study area is a headwaters catchment of the Bow River, which flows eastward to provide an important supply of water to the Canadian prairies. Meteorological, snowpack, and surface energy balance data collected at Haig Glacier from 2002 to 2013 were analysed to evaluate glacier mass balance and run-off. Annual specific discharge from snow- and ice-melt on Haig Glacier averaged 2350 mm water equivalent from 2002 to 2013, with 42% of the run-off derived from melting of glacier ice and firn, i.e. water stored in the glacier reservoir. This is an order of magnitude greater than the annual specific discharge from non-glacierized parts of the Bow River basin. From 2002 to 2013, meltwater derived from the glacier storage was equivalent to 5-6% of the flow of the Bow River in Calgary in late summer and 2-3% of annual discharge. The basin is typical of most glacier-fed mountain rivers, where the modest and declining extent of glacierized area in the catchment limits the glacier contribution to annual run-off.

  3. Review of "Taking Control: Power and Contradiction in First Nations Adult Education," by Celia Haig-Brown.

    ERIC Educational Resources Information Center

    Fee, Margery

    1996-01-01

    Reviews an ethnography of the Native Education Centre (NEC) in Vancouver (British Columbia) that focuses on the degree to which NEC's programs demonstrate "Indian control of Indian education." Discusses the book's central questions and contradictions concerning who is native, use of nonnative teachers, and the role of native education--cultural…

  4. Putting Concepts and Constructs into Practice: A Reply to Cervone and Caldwell, Haig, Kane, Mislevy, and Rupp

    ERIC Educational Resources Information Center

    Markus, Keith A.

    2008-01-01

    The commentary has greatly enriched the discussion initiated by the three target articles. The distinction between constructs and concepts contributes to both the top-down and bottom-up aspects of the dialectic between measurement theory and practice. The distinction also illuminates the abstraction from observation to manifest variables. However,…

  5. Revision of Lissoporcellana streptochiroides (Johnson, 1970) (Crustacea: Decapoda: Anomura: Porcellanidae), with description of a new species of Lissoporcellana Haig, 1978 from Beibu Bay, South China Sea.

    PubMed

    Dong, Dong; Li, Xinzheng

    2014-01-01

    A new porcellanid crab, Lissoporcellana demani n. sp. is described based on material from the Beibu Bay in the northern South China Sea. The new species can be distinguished from other congeners by the shape of rostrum, form of fixed finger of smaller cheliped and armature of lateral margins of carapace. The poorly known species L. streptochiroides (Johnson, 1970), which resembles L. demani n. sp. in carapace shape, is redescribed on the basis of examination of the syntypes from Singapore and transferred to Pisidia Leach, 1820. 

  6. 78 FR 65977 - Board of Visitors, United States Military Academy (USMA)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... of Visitors. 2. Date: Wednesday, October 16, 2013. 3. Time: 2:00 p.m.-5:30 p.m. 4. Location: Haig... Point of Contact: Ms. Deadra Ghostlaw, (845) 938-4200, Deadra.Ghostlaw@us.army.mil . 7. Due to the...

  7. Petrogenesis of Augite-bearing Ureilites: A LA-ICP-MS Approach

    NASA Astrophysics Data System (ADS)

    Huang, S.; Humayun, M.; Downes, H.; Singletary, S.; van Orman, J. A.; Jacobsen, S. B.

    2009-03-01

    Major, minor and trace elements have been determined on silicate minerals from ureilites LAR 04315, North Haig and FRO 93008 using LA-ICP-MS. The element compositions in ureilite minerals are consistent with ureilites being melting/smelting restites from a spinel peridotite.

  8. 75 FR 65006 - Board of Visitors, United States Military Academy (USMA)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ....m.-3 p.m. ADDRESSES: Jefferson Hall Library, Haig Room, West Point, NY. FOR FURTHER INFORMATION... meeting location. All participants are subject to security screening. 4. Location: Jefferson Hall Library... Academy leadership will provide the Board updates on the following: Education and Academic...

  9. Treating the Pathology of Psychometrics: An Example from the Comprehension of Continuous Prose Text

    ERIC Educational Resources Information Center

    Kyngdon, Andrew

    2008-01-01

    Few would argue that psychology has been as successful as the natural sciences in constructing measurement systems, yet this has not tempered the near universal claim of psychological measurement. As Haig and Denny Borsboom note, the sustained nature of conceptual attacks from a small group of quantitative psychologists suggests a deep-seated…

  10. On Prototypes and Paradigm Shifts

    ERIC Educational Resources Information Center

    McGrath, Robert E.

    2009-01-01

    The author agrees with the editors of this informative series of articles (Haig & Borsboom, 2008) that the number of articles appearing in recent years questioning basic assumptions about psychosocial measurement instruments, such as their mathematical qualities and their potential as valid indicators, augurs well for serious reconsideration of…

  11. Scientific Symbiosis Represents the Mutual Benefit of Iteratively Adopting the Perspective of Realism and Instrumentalism

    ERIC Educational Resources Information Center

    Cacioppo, John T.; Berntson, Gary G.; Semin, Gu R.

    2005-01-01

    This article presents comments on "Psychology Needs Realism not Instrumentalism" by B. Haig, "Ontological and Epistemic Claims of Realism and Instrumentalism" by Lau and "The Scientific Denial of the Real and the Dialectic of Scientism and Humanism" by Ramey and Chrysikou which were all comments on the original article "Realism, Instrumentalism,…

  12. Physiological responses in potato plants under continuous irradiation

    NASA Technical Reports Server (NTRS)

    Cao, W.; Tibbitts, T. W.

    1991-01-01

    The physiological responses of four potato (Solanum tuberosum L.) cultivars to continuous irradiation were determined in a controlled environment. Under a constant 18C and a constant photoperiod of 470 micromoles s-1 m-2 of photosynthetic photon flux, 'Denali' and 'Haig' grew well and produced large plant and tuber dry weights when harvested 56 days after transplanting. 'Kennebec' and 'Superior' were severely stunted, producing only 10% of the plant dry matter produced by 'Denali' and 'Haig'. The differences in leaf chlorophyll concentration and stomatal conductance were not consistent between these two groups of cultivars. The leaf net CO2 assimilation rates in 'Kennebec' and 'Superior' were lower, and intercellular CO2 partial pressures were higher than in 'Denali' and 'Haig'. These results indicate that inhibition of net CO2 assimilation in 'Kennebec' and 'Superior' was not due to a limiting amount of chlorophyll or to CO2 in the leaf tissues. Concentrations of starch in leaflets of 'Kennebec' and 'Superior' plants were only 10% of those in 'Denali' and 'Haig' plants, although soluble sugar concentrations were similar in the four cultivars. Therefore, the lower net CO2 assimilation rates in stunted 'Kennebec' and 'Superior' plants were not associated with an excess carbohydrate accumulation in the leaves.

  13. Utilization of potatoes for life support in space. V. Evaluation of cultivars in response to continuous light and high temperature

    NASA Technical Reports Server (NTRS)

    Tibbitts, T. W.; Cao, W.; Bennett, S. M.

    1992-01-01

    Twenty-four potato (Solanum tuberosum L.) cultivars from different regions of the world were evaluated in terms of their responses to continuous light (24 h photoperiod) and to high temperature (30 C) in two separate experiments under controlled environments. In each experiment, a first evaluation of the cultivars was made at day 35 after transplanting, at which time 12 cultivars exhibiting best growth and tuber initiation were selected. A final evaluation of the 12 cultivars was made after an additional 21 days of growth, at which time plant height, total dry weight, tuber dry weight, and tuber number were determined. In the continuous light evaluation, the 12 selected cultivars were Alaska 114, Atlantic, Bintje, Denali, Desiree, Haig, New York 81, Ottar, Rutt, Snogg, Snowchip, and Troll. In the high temperature evaluation, the 12 selected cultivars were Alpha, Atlantic, Bake King, Denali, Desiree, Haig, Kennebec, Norland, Russet Burbank, Rutt, Superior, and Troll. Among the cultivars selected under continuous irradiation, Desiree, Ottar, Haig, Rutt, Denali and Alaska showed the best potential for high productivity whereas New York 81 and Bintje showed the least production capability. Among the cultivars selected under high temperature, Rutt, Haig, Troll and Bake King had best performance whereas Atlantic, Alpha, Kennebec and Russet Burbank exhibited the least production potential. Thus, Haig and Rutt were the two cultivars that performed well under continuous irradiation and high temperature conditions, and could have maximum potential for adaptation to varying stress environments. These two cultivars may have the best potential for use in future space farming in which continuous light and/or high temperature conditions may exist. However, cultivar responses under combined conditions of continuous light and high temperature remains for further validation.

  14. Thermomagnetic analysis of meterorites. 4: Ureilites

    NASA Technical Reports Server (NTRS)

    Rowe, M. W.; Herndon, J. M.; Larson, E. E.; Watson, D. E.

    1974-01-01

    Samples of all available ureilites have been analyzed thermomagnetically. For three of the six (Dyalpur, Goalpara and Havero) evidence was found for only low-nickel metallic-iron as the magnetic component and the (saturation magnetization vs, temperature) curves were reversible. In the Novo Urei ureilite, magnetite in addition to low-nickel metallic-iron was indicated and again the Js-T curve was reversible. For the two badly weathered ureilites, Dingo Pup Donga and North Haig, indication was also found that both initial magnetite and low-nickel metallic-iron were present. However, the Js-T curves were somewhat irreversible and the final saturation magnetization was 20% and 50% greater than initially for North Haig and Dingo Pup Donga, respectively. This behavior is interpreted to be the result of magnetite production from a secondary iron oxide during the experiment.

  15. Resisting biology. The unpopularity of a gene's-eye view.

    PubMed

    Terleph, T A

    2000-04-01

    David Haig's intragenomic conflict theory concerning the possible evolutionary origins of genomic imprinting is discussed. It is suggested that a useful way in which one might represent Haig's theory to a popular audience would be by emphasizing a gene's eye viewpoint. In doing so, an author may help to dispel common misconceptions about evolution and natural selection, misconceptions which arise in part from an overemphasis on the individual, rather than the gene, when discussing natural selection. Although it is possible to view either the gene or the individual as a unit of natural selection, our own proclivity towards overemphasizing the role of individuals in evolution is seen as a common impediment to a more complete understanding of both natural selection, as well as the philosophical implications arising from a gene's eye view of evolutionary theory.

  16. Advances in Modelling of Valley Glaciers

    NASA Astrophysics Data System (ADS)

    Adhikari, Surendra

    For glaciological conditions typical of valley glaciers, the central idea of this research lies in understanding the effects of high-order mechanics and parameterizing these for simpler dynamical and statistical methods in glaciology. As an effective tool for this, I formulate a new brand of dynamical models that describes distinct physical processes of deformational flow. Through numerical simulations of idealized glacier domains, I calculate empirical correction factors to capture the effects of longitudinal stress gradients and lateral drag for simplified dynamical models in the plane-strain regime. To get some insights into real glacier dynamics, I simulate Haig Glacier in the Canadian Rocky Mountains. As geometric effects overshadow dynamical effects in glacier retreat scenarios, it appears that high-order physics are not very important for Haig Glacier, particularly for evaluating its fate. Indeed, high-order and reduced models all predict that Haig Glacier ceases to exist by about AD2080 under ongoing climate warming. This finding regarding the minimal role of high-order physics may not be broadly valid, as it is not true in advance scenarios at Haig Glacier and it may not be representative of other glaciological settings. Through a 'bulk' parameterization of high-order physics, geometric and climatic settings, sliding conditions, and transient effects, I also provide new insights into the volume-area relation, a widely used statistical method for estimating glacier volume. I find a steady-state power-law exponent of 1:46, which declines systematically to 1:38 after 100 years of sustained retreat, in good accord with the observations. I recommend more accurate scaling relations through characterization of individual glacier morphology and degree of climatic disequilibrium. This motivates a revision of global glacier volume estimates, of some urgency in sea level rise assessments.

  17. [Morphology of the first zoea of the marine crabs Petrolisthes haigae and P. nobilii (Decapoda: Porcellanidae)].

    PubMed

    Hernández, Gonzalo; Bolaños, Juan; Magán, Isabel; Graterol, Karen

    2007-01-01

    The porcellanid crabs Petrolisthes haigae Chace 1962, and P nobilii Haig 1960, are shallow-water species distributed along the tropical Eastern Pacific shores. Larvae of both species from eight and four females, collected at Taboga and Naos Islands, respectively, were hatched in the laboratory. First zoeal stages of these species are described and illustrated for the first time and compared to previously first zoeae of other congeneric species from western Panama. Characters of the first zoeae of both species most closely agree with those Osawa's (2002) Group 4 of larvae. PMID:19086392

  18. Fluorescent accessory phases in the carbonaceous matrix of ureilites

    NASA Technical Reports Server (NTRS)

    Berkley, J. L.; Taylor, G. J.; Keil, K.; Healey, J. T.

    1978-01-01

    The carbonaceous matrix of ureilite meteorites (C-bearing olivine-pigeonite achondrites) contain abundant minute phases that emit a multicolored fluorescence under electron bombardment. These include NaCl and KCl, found in all seven ureilites studied, high-Si glass with pyroxene and chlorapatite quench crystals in North Haig, an unidentified high-Ca-Al-Cl phase in Novo Urei, and possibly free SiO2 in Novo Urei and Dingo Pup Donga. The origin of these phases is uncertain but some, especially chlorides and glass, may represent residual postcumulus materials precipitated from a late-stage interstitial liquid during the igneous phase of ureilite history.

  19. Genetic Applications in Avian Conservation

    USGS Publications Warehouse

    Haig, Susan M.; Bronaugh, Whitcomb M.; Crowhurst, Rachel S.; D'Elia, Jesse; Eagles-Smith, Collin A.; Epps, Clinton W.; Knaus, Brian; Miller, Mark P.; Moses, Michael L.; Oyler-McCance, Sara; Robinson, W. Douglas; Sidlauskas, Brian

    2011-01-01

    A fundamental need in conserving species and their habitats is defining distinct entities that range from individuals to species to ecosystems and beyond (Table 1; Ryder 1986, Moritz 1994, Mayden and Wood 1995, Haig and Avise 1996, Hazevoet 1996, Palumbi and Cipriano 1998, Hebert et al. 2004, Mace 2004, Wheeler et al. 2004, Armstrong and Ball 2005, Baker 2008, Ellis et al. 2010, Winker and Haig 2010). Rapid progression in this interdisciplinary field continues at an exponential rate; thus, periodic updates on theory, techniques, and applications are important for informing practitioners and consumers of genetic information. Here, we outline conservation topics for which genetic information can be helpful, provide examples of where genetic techniques have been used best in avian conservation, and point to current technical bottlenecks that prevent better use of genomics to resolve conservation issues related to birds. We hope this review will provide geneticists and avian ecologists with a mutually beneficial dialogue on how this integrated field can solve current and future problems.

  20. Co/Ni ratios at taenite/kamacite interfaces and relative cooling rates in iron meteorites

    NASA Astrophysics Data System (ADS)

    Wasson, John T.; Hoppe, Peter

    2012-05-01

    We report a pilot study of a new technique to use the distribution of Co between kamacite and taenite to infer relative cooling rates of iron meteorites; data of Widge and Goldstein (1977) showed that the distribution is temperature dependent. A plot of the logarithm of the double ratio [(Co/Ni)kamacite/(Co/Ni)taenite] (abbreviated Rαγ) against inverse temperature yields a linear equation showing that the ratio ranges from ˜2.5 at 1080 K to ˜30 at 710 K. Thus, a measurement of Rαγ in the kamacite and taenite near the interface offers information about relative cooling rates; the higher Rαγ, the lower the cooling rate. A major advantage of this technique is that it is mainly affected by the final (low-temperature) cooling rate, just before the sample cooled to the blocking temperature where diffusion became insignificant. To test this method we used the NanoSIMS ion probe to measure Rαγ in two IVA and two IIIAB irons; members of each pair differ by large factors in elemental composition and in published metallographic cooling rates (Yang and Goldstein, 2006; Yang et al., 2008). Despite differing by a factor of 25 in estimated metallographic cooling rate, the two IVA irons showed similar Rαγ values of ˜22. If experimental uncertainties are considered this implies that, at low temperatures, their cooling rates differ by less than a factor of 5 with 95% confidence, i.e., significantly less than the range in metallographic cooling rates. In contrast, the IIIAB irons have different ratios; Rαγ in Haig is 29 whereas that in Cumpas, with a reported cooling rate 4.5 times lower, is 22, the opposite of that expected from the published cooling rates. A reevaluation of the Yang-Goldstein IIIAB data set shows that Haig has anomalous metallographic properties. We suggest that both the high Rαγ in Haig and the systematically low taenite central Ni contents are the result of impact-produced fractures in the taenite that allowed equilibration with kamacite down to

  1. Oil diplomacy: the Atlantic nations in the oil crisis of 1978-79

    SciTech Connect

    Not Available

    1980-01-01

    Six essays examine how the US, Western Europe, and Japan have handled their common energy problems and to what extent their traditional cooperation has been enhanced or diminished by the OPEC actions. They explore the interdependencies of the developed countries, along with the strains that the energy crisis has placed on the search for common solutions. An introduction by Alexander Haig is followed by essays titled: The Permanent Crisis: Change in the World Oil System; The American Response: On-the-Job Training; Western Europe: A Fragmented Response to a Fragmenting Order; The West in Concert: A Very Complex Score; Politics of Dependence: Western Europe and the Arab-Israeli Conflict; Oil on Troubled Waters: The Industrial World and the OPEC; Oil and Money: A Note on the Western Financial Community; and Getting Out of the Crisis: excerpt of interviews. 2 tables. (DCK)

  2. Aluminum-26 in meteorites. VII - Ureilites, their unique radiation history.

    NASA Technical Reports Server (NTRS)

    Wilkening, L. L.; Herman, G. F.; Anders, E.

    1973-01-01

    Cosmogenic Al-26 activities have been measured by gamma-gamma coincidence counting in the three ureilites which had not previously been studied. The values in dpm/kg are: Dingo Pup Donga, 38.4 plus or minus 2.4; North Haig, 39.3 plus or minus 4.8; Dyalpur, 55.8 plus or minus 4.8. Five of the six known ureilites thus have lower Al-26 contents, 63 per cent to 77 per cent, than the calculated saturation values, in marked contrast to most other stony meteorites. This cannot be attributed to short cosmic ray exposure ages. The most likely explanation is that the ureilites had much smaller or much larger orbits than all other stony meteorites.

  3. Nature of the carbon and sulfur phases and inorganic gases in the Kenna ureilite

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.

    1976-01-01

    Abundances of carbon and sulfur in the Kenna ureilite are 2.219 plus or minus 0.060 wt. % C and 0.179 plus or minus 0.008 wt. % S. Secondary carbonates resulting from terrestrial weathering account for 0.25 plus or minus 0.02 wt. % C. No hydrocarbons were detected during gas release measurements. Most of the carbon is in graphite, diamond, or lonsdaleite. The sample of Kenna contained 0.95 plus or minus 0.05 wt.% H2O. Total carbon and sulfur measurements were made on three additional ureilites: Havero, Dingo Pup Donga, and North Haig. Ureilite carbon abundances are similar to those of C-2 chondrites, whereas sulfur abundances are a factor of 10 less than C-2 chondrites and ordinary chondrites. The elemental abundances, ratios, and phases present in the ureilites rule out a direct genetic relationship between the ureilites and the carbonaceous chondrites.

  4. Psychometrically appropriate assessment of afocal optics by measurement of the Strehl intensity ratio

    NASA Astrophysics Data System (ADS)

    Haig, Nigel D.; Williams, T. L.

    1995-04-01

    Several different performance criteria have been proposed for assessing the quality of visual afocal sights. Earlier research by one of the authors (Haig) has shown that a high degree of correlation exists between a subjective assessment of performance and the Strehl intensity ratio of the optical system. We discuss some of the problems in choosing an objective performance criterion for visual sights and describe equipment that has been developed for measuring the line Strehl ratio of binoculars, both on and off axes. The equipment can be modified for testing other types of visual sight. It can also be used for measuring several additional performance parameters such as the modulation transfer function, transmission, and field curvature.

  5. Future climate-driven glacier energy balance change in the Canadian Rockies using the CMIP5

    NASA Astrophysics Data System (ADS)

    Ebrahimi, Samaneh

    2016-04-01

    A fundamental understanding of the climate and the Earth's system is necessary to interpret the short- and long-term impacts of climate change. The interaction between glaciers and climate is a sensitive relationship and and calculating variations in glacier energy is key to estimating future change. It is difficult, however, to accurately project future glacier change due to the complexity in the dynamics controlling glacier response to climate. The primary goal of this paper is to illustrate the future climate-driven glacier change on Haig Glacier, located in the Canadian Rockies. Therefore, the CM3 physical model of the GFDL center for the CMIP5 set of experiments was used to examine the future surface energy balance change. Daily meteorological variables from the historical and future projections under four radiative forcing pathways of RCP2.6, RCP4.5, RCP6.0 and RCP8.6 were used to conduct the full energy balance modeling for Haig Glacier. These scenarios range in complexity and reflect long-term trends (decades to centuries). Hence, changes in the different incoming and outgoing energy from the glacier surface were examined during different decades for different pathways. The data used for these calculations was limited to the summer melt season, May through September (MJJAS), in both the historical and future experiments, from 1975-2100. The results shows that, relative to the control baseline period (1975 to 2005), the glacier's mass balance will be in a moderately stable condition with only a slight increase in melt energy until about mid-century. This relatively stable period will be followed by a sudden acceleration in melt energy around 2050 which increases more than 100% of the baseline amount by the end of 21st century, depending on different pathways.

  6. Paleomagnetism of Silver Island, Keweenaw Peninsula, Michigan: Additional Support (?) for the Primary Curvature of the MCR

    NASA Astrophysics Data System (ADS)

    Diehl, J. F.; Durant, A. J.; Schepke, C.

    2009-05-01

    Silver Island lies between Eagle Harbor and Copper Harbor on the NW coastline of the Keweenaw Peninsula, Michigan. The island consists of a series of basaltic lava flows which dip to the north-northwest (356°) at an angle of approximately 38°. These flows constitute part of the Lake Shore Traps (LST), a series of interbedded lava flows within the Copper Harbor Conglomerate (CHC). The LST represent the youngest eruptive material associated with the 1.1 Ga Mid-Continent Rift (MCR). The most recent paleomagnetic study (now 15 years old) on the Lakeshore Traps (LST) defined three distinct directional clusters. Each cluster of directions corresponded to a different stratigraphic package of the LST within the CHC and all have extremely low between-site dispersion (s ˜ 4°) suggesting rather rapid emplacement of the LST packages. Consequently, each cluster has its own unique direction of magnetization. Since the lower two LST packages crop out along the coast line of the Peninsula with different structural trends, an opportunity was presented to test the conclusions of Hnat et al. (2006) that the curvature of the MCR was primary. To that end nine lava flows were sampled on Silver Island and their mean direction compared to the equivalent mean from lava flows sampled by Diehl and Haig (1994) from the tip of the Keweenaw Peninsula (upper lava flows of the Middle LST) which have an entirely different structural trend. Characteristic directions of magnetization of the Silver Island lava flows were isolated either using alternating field, thermal or a combination of both. The mean direction of magnetization for the nine sites is: D = 277.7°, I = 46.9°, α95 = 3.0°, k = 292.5. The mean direction recalculated from the Diehl and Haig study is: D = 277.8°, I = 40.6°, α95 = 2.9°, k = 315.7. Although the declinations of the two means are identical, interestingly the two means are statistically distinct at the 95% confidence level. Fold tests were inconclusive. Nevertheless

  7. The evolution of genomic imprinting: theories, predictions and empirical tests.

    PubMed

    Patten, M M; Ross, L; Curley, J P; Queller, D C; Bonduriansky, R; Wolf, J B

    2014-08-01

    The epigenetic phenomenon of genomic imprinting has motivated the development of numerous theories for its evolutionary origins and genomic distribution. In this review, we examine the three theories that have best withstood theoretical and empirical scrutiny. These are: Haig and colleagues' kinship theory; Day and Bonduriansky's sexual antagonism theory; and Wolf and Hager's maternal-offspring coadaptation theory. These theories have fundamentally different perspectives on the adaptive significance of imprinting. The kinship theory views imprinting as a mechanism to change gene dosage, with imprinting evolving because of the differential effect that gene dosage has on the fitness of matrilineal and patrilineal relatives. The sexual antagonism and maternal-offspring coadaptation theories view genomic imprinting as a mechanism to modify the resemblance of an individual to its two parents, with imprinting evolving to increase the probability of expressing the fitter of the two alleles at a locus. In an effort to stimulate further empirical work on the topic, we carefully detail the logic and assumptions of all three theories, clarify the specific predictions of each and suggest tests to discriminate between these alternative theories for why particular genes are imprinted. PMID:24755983

  8. The evolution of genomic imprinting: theories, predictions and empirical tests

    PubMed Central

    Patten, M M; Ross, L; Curley, J P; Queller, D C; Bonduriansky, R; Wolf, J B

    2014-01-01

    The epigenetic phenomenon of genomic imprinting has motivated the development of numerous theories for its evolutionary origins and genomic distribution. In this review, we examine the three theories that have best withstood theoretical and empirical scrutiny. These are: Haig and colleagues' kinship theory; Day and Bonduriansky's sexual antagonism theory; and Wolf and Hager's maternal–offspring coadaptation theory. These theories have fundamentally different perspectives on the adaptive significance of imprinting. The kinship theory views imprinting as a mechanism to change gene dosage, with imprinting evolving because of the differential effect that gene dosage has on the fitness of matrilineal and patrilineal relatives. The sexual antagonism and maternal–offspring coadaptation theories view genomic imprinting as a mechanism to modify the resemblance of an individual to its two parents, with imprinting evolving to increase the probability of expressing the fitter of the two alleles at a locus. In an effort to stimulate further empirical work on the topic, we carefully detail the logic and assumptions of all three theories, clarify the specific predictions of each and suggest tests to discriminate between these alternative theories for why particular genes are imprinted. PMID:24755983

  9. An experiment to fly on mission STS-93 is prepared at Life Sciences Building, CCAS

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In the KSC Life Sciences Building, Hangar L, Cape Canaveral Air Station, Dr. Haig Keshishian checks fruit fly larvae in a petri dish. The larvae are part of an experiment that is a secondary payload on mission STS-93. The experiment will examine the effects of microgravity and space flight on the development of neural connections between specific motor neurons and their targets in muscle fibers. Dr. Keshishian, from Yale University, is the principle investigator for the experiment. The larvae will be contained in incubators that are part of a Commercial Generic Bioprocessing Apparatus (CGBA), which can start bioprocessing reactions by mixing or heating a sample and can also initiate multiple-step, sequential reactions in a technique called phased processing. The primary payload of mission STS-93 is the Chandra X-ray Observatory, which will allow scientists from around the world to see previously invisible black holes and high- temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. The target launch date for STS-93 is July 9, aboard Space Shuttle Columbia, from Launch Pad 39B.

  10. Local gain control and focal accommodation in the Self Similar Stack vision model.

    PubMed

    Haig, N D

    1993-01-01

    The aim of this paper is to report an extension to the computationally efficient Self Similar Stack model (Burton et al. Biol., Cybernet. 53, 397-403, 1986) to include the effects of local gain control in the retina. The method employed to do this has been to fit a family of difference-of-Gaussian functions to the human contrast sensitivity function curves of van Nes and Bouman (J. Opt. Soc. Am. 57, 401-406, 1967). The centre frequencies of the DoGs within each family are octave-related, in a simplified manifestation of the DoG channels found by Wilson et al. (Vision Res. 23, 873-882, 1983). The sensitivity of each level, or channel, that formed the original Stack model is modulated individually according to the fitted values, as the local illumination varies within an image. The model was tested against psychometric data obtained by Haig and Burton (Appl. Optics 26, 492-500, 1987) during experiments on visual discrimination. The consistency of the results indicates the validity of the approximations and the robustness of the model, either for machine vision purposes or for predicting human visual performance. A simple algorithm, developed for use with a machine vision application of this model, provides a means by which a TV camera may be focused automatically. The success of this algorithm, using the newly computed channel sensitivities, suggests that human focal accommodation may be regulated by a similar form of mechanism. PMID:8494807

  11. The evolution of genomic imprinting: theories, predictions and empirical tests.

    PubMed

    Patten, M M; Ross, L; Curley, J P; Queller, D C; Bonduriansky, R; Wolf, J B

    2014-08-01

    The epigenetic phenomenon of genomic imprinting has motivated the development of numerous theories for its evolutionary origins and genomic distribution. In this review, we examine the three theories that have best withstood theoretical and empirical scrutiny. These are: Haig and colleagues' kinship theory; Day and Bonduriansky's sexual antagonism theory; and Wolf and Hager's maternal-offspring coadaptation theory. These theories have fundamentally different perspectives on the adaptive significance of imprinting. The kinship theory views imprinting as a mechanism to change gene dosage, with imprinting evolving because of the differential effect that gene dosage has on the fitness of matrilineal and patrilineal relatives. The sexual antagonism and maternal-offspring coadaptation theories view genomic imprinting as a mechanism to modify the resemblance of an individual to its two parents, with imprinting evolving to increase the probability of expressing the fitter of the two alleles at a locus. In an effort to stimulate further empirical work on the topic, we carefully detail the logic and assumptions of all three theories, clarify the specific predictions of each and suggest tests to discriminate between these alternative theories for why particular genes are imprinted.

  12. Summer deposition of sulfate and reactive nitrogen to two alpine valleys in the Canadian Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Wasiuta, Vivian; Lafrenière, Melissa J.; Norman, Ann-Lise; Hastings, Meredith G.

    2015-01-01

    Summer deposition of sulfate and reactive nitrogen (mainly nitrate, and ammonium) to two alpine valleys in the Southern Canadian Rocky Mountains was investigated to constrain their major sources and evaluate physiographic influences on deposition. The effects of elevation, aspect, and air mass trajectory were evaluated using stable isotope composition (δ15N-NO3-, δ18O-NO3-, and δ34S-SO42-) and major ion concentrations for bulk precipitation. Deposition in the two valleys was related to synoptic scale weather conditions and the route the air mass followed, the location of major emission sources relative to the study site, and atmospheric residence time. Distinct differences in deposition at a relatively small scale between two opposing alpine valleys was mainly related to the orientation of the two valleys relative to the physiography of the Western Canadian Cordillera and the dominant pathways of air mass transport. Sulfate was found to be dominantly from distant sources, while NO3- was strongly enhanced by emissions from local to regional combustion. Local to regional pollutants were preferentially transported to the NNW facing Robertson Valley during NW-upslope synoptic conditions while precipitation in the SE facing Haig Valley was from relatively clean air with minimal influence from local and regional pollutants particularly at the highest elevation site.

  13. Electroluminescent TCC, C3dg and fB/Bb epitope assays for profiling complement cascade activation in vitro using an activated complement serum calibration standard.

    PubMed

    van Vuuren, B Jansen; Bergseth, G; Mollnes, T E; Shaw, A M

    2014-01-15

    Electroluminescent assays for epitopes on the complement components C3dg, terminal complement complex (TCC) and factor B/Bb (fB/Bb) have been developed with capture and detection antibodies to produce detection limits C3dg=91±9ng/mL, TCC=3±0.1ng/mL and fB=55.7±0.1ng/mL. The assay performance was assessed against a series of zymosan and heat aggregated IgG (HAIgG) in vitro activations of complement using a calibrated activated complement serum (ACS) as calibration standard. The ACS standard was stable within 20% accuracy over a 6-month period with freeze-thaw cycles as required. Differential activation of the complement cascade was observed for TCC showing a pseudo-first order formation half-life of 3.5h after activation with zymosan. The C3dg activation fragment indicates a 10% total activation for both activation agents. The kinetic-epitope analysis for fB indicates that the capture epitope is on the fB/Bb protein fragment which can then become covered by the formation of C3bBb or C3bBbP complexes during the time course of the cascade.

  14. Temperature cycling periods affect growth and tuberization in potatoes under continuous irradiation

    NASA Technical Reports Server (NTRS)

    Cao, W.; Tibbitts, T. W.

    1992-01-01

    Plants of the potato (Solanum tuberosum L.) cultivars Denali, Norland, Haig and Kennebec were grown for 42 days under three temperature cycling periods (thermoperiods) with continuous irradiation in two repeated experiments to help determine if temperature cycling might be varied to optimize tuber development of potatoes in controlled environments. Thermoperiods of 6/6 hours, 12/12 hours and 24/24 hours were established with the same temperature change of 22/14C and same controlled vapor pressure deficit of 0.60 kPa. The thermoperiod of 24/24 hours significantly promoted tuber initiation but slowed tuber enlargement in all four cultivars, compared to the thermoperiods of 6/6 hours and 12/12 hours. Denali' produced the highest tuber and total dry weights under the 6/6 hours thermoperiod. Kennebec' produced the highest tuber dry weight under the 12/12 hours thermoperiod. Thermoperiods had no significant effect on shoot and root dry weights of any cultivars. The major effect of thermoperiods was on initiation and enlargement of tubers.

  15. Comparisons of likelihood and machine learning methods of individual classification

    USGS Publications Warehouse

    Guinand, B.; Topchy, A.; Page, K.S.; Burnham-Curtis, M. K.; Punch, W.F.; Scribner, K.T.

    2002-01-01

    “Assignment tests” are designed to determine population membership for individuals. One particular application based on a likelihood estimate (LE) was introduced by Paetkau et al. (1995; see also Vásquez-Domínguez et al. 2001) to assign an individual to the population of origin on the basis of multilocus genotype and expectations of observing this genotype in each potential source population. The LE approach can be implemented statistically in a Bayesian framework as a convenient way to evaluate hypotheses of plausible genealogical relationships (e.g., that an individual possesses an ancestor in another population) (Dawson and Belkhir 2001;Pritchard et al. 2000; Rannala and Mountain 1997). Other studies have evaluated the confidence of the assignment (Almudevar 2000) and characteristics of genotypic data (e.g., degree of population divergence, number of loci, number of individuals, number of alleles) that lead to greater population assignment (Bernatchez and Duchesne 2000; Cornuet et al. 1999; Haig et al. 1997; Shriver et al. 1997; Smouse and Chevillon 1998). Main statistical and conceptual differences between methods leading to the use of an assignment test are given in, for example,Cornuet et al. (1999) and Rosenberg et al. (2001). Howeve

  16. New taxonomic and distributional information on hermit crabs (Crustacea: Anomura: Paguroidea) from the Gulf of Mexico, Caribbean Sea, and Atlantic coast of South America.

    PubMed

    Lemaitre, Rafael; Tavares, Marcos

    2015-01-01

    A collection of Paguroidea recently obtained during deep-water expeditions along the coast of Brazil, forms the basis of this report. Of the 14 species reported from Brazil, 11 represent range extensions to the south, and one, Michelopagurus atlanticus (Bouvier, 1922), is a first record for the western Atlantic. The specimens were compared with types and western Atlantic materials deposited in various major museums. A diagnosis and illustrations are presented for each of seven species found to be poorly or insufficiently known. New material and information is reported for two additional species that occur in Brazil but not found in the recent deep-water collections: Clibanarius symmetricus (Randall, 1840) and Mixtopagurus paradoxus A. Milne-Edwards, 1880. Remarkable and unique color photographs of live or fresh specimens of Allodardanus bredini Haig & Provenzano, 1965, Bathynarius anomalus (A. Milne-Edwards & Bouvier, 1893), Pylopagurus discoidalis (A. Milne-Edwards, 1880), Paguristes spinipes A. Milne-Edwards, 1880, Parapagurus pilosimanus Smith, 1876, and P. alaminos Lemaitre, 1986, are presented. A review of published records and museum collections of the terrestrial Coenobita clypeatus (Fabricius, 1787), has shown that the southern range limit of this species does not extend beyond the southern Caribbean and Trinidad and Tobago, and thus does not occur on the Brazilian coast as previously believed. A distribution map of C. clypeatus is provided based on specimens in the collections of the National Museum of Natural History, Smithsonian Institution. New distribution records in the Gulf of Mexico and southern Caribbean, and morphological information, are included for Pagurus rotundimanus Wass, 1963, a species originally described from the Florida Keys but rarely reported since. Relevant remarks on the taxonomy, morphology, and distribution of all these species are included. The revised list of Paguroidea known from Brazil is updated, and now includes a total of

  17. New taxonomic and distributional information on hermit crabs (Crustacea: Anomura: Paguroidea) from the Gulf of Mexico, Caribbean Sea, and Atlantic coast of South America.

    PubMed

    Lemaitre, Rafael; Tavares, Marcos

    2015-01-01

    A collection of Paguroidea recently obtained during deep-water expeditions along the coast of Brazil, forms the basis of this report. Of the 14 species reported from Brazil, 11 represent range extensions to the south, and one, Michelopagurus atlanticus (Bouvier, 1922), is a first record for the western Atlantic. The specimens were compared with types and western Atlantic materials deposited in various major museums. A diagnosis and illustrations are presented for each of seven species found to be poorly or insufficiently known. New material and information is reported for two additional species that occur in Brazil but not found in the recent deep-water collections: Clibanarius symmetricus (Randall, 1840) and Mixtopagurus paradoxus A. Milne-Edwards, 1880. Remarkable and unique color photographs of live or fresh specimens of Allodardanus bredini Haig & Provenzano, 1965, Bathynarius anomalus (A. Milne-Edwards & Bouvier, 1893), Pylopagurus discoidalis (A. Milne-Edwards, 1880), Paguristes spinipes A. Milne-Edwards, 1880, Parapagurus pilosimanus Smith, 1876, and P. alaminos Lemaitre, 1986, are presented. A review of published records and museum collections of the terrestrial Coenobita clypeatus (Fabricius, 1787), has shown that the southern range limit of this species does not extend beyond the southern Caribbean and Trinidad and Tobago, and thus does not occur on the Brazilian coast as previously believed. A distribution map of C. clypeatus is provided based on specimens in the collections of the National Museum of Natural History, Smithsonian Institution. New distribution records in the Gulf of Mexico and southern Caribbean, and morphological information, are included for Pagurus rotundimanus Wass, 1963, a species originally described from the Florida Keys but rarely reported since. Relevant remarks on the taxonomy, morphology, and distribution of all these species are included. The revised list of Paguroidea known from Brazil is updated, and now includes a total of

  18. Perspective: maternal kin groups and the origins of asymmetric genetic systems-genomic imprinting, haplodiploidy, and parthenogenesis.

    PubMed

    Normark, Benjamin B

    2006-04-01

    The genetic systems of animals and plants are typically eumendelian. That is, an equal complement of autosomes is inherited from each of two parents, and at each locus, each parent's allele is equally likely to be expressed and equally likely to be transmitted. Genetic systems that violate any of these eumendelian symmetries are termed asymmetric and include parent-specific gene expression (PSGE), haplodiploidy, thelytoky, and related systems. Asymmetric genetic systems typically arise in lineages with close associations between kin (gregarious siblings, brooding, or viviparity). To date, different explanatory frameworks have been proposed to account for each of the different asymmetric genetic systems. Haig's kinship theory of genomic imprinting argues that PSGE arises when kinship asymmetries between interacting kin create conflicts between maternally and paternally derived alleles. Greater maternal than paternal relatedness within groups selects for more "abstemious" expression of maternally derived alleles and more "greedy" expression of paternally derived alleles. Here, I argue that this process may also underlie origins of haplodiploidy and many origins of thelytoky. The tendency for paternal alleles to be more "greedy" in maternal kin groups means that maternal-paternal conflict is not a zero-sum game: the maternal optimum will more closely correspond to the optimum for family groups and demes and for associated entities such as symbionts. Often in these circumstances, partial or complete suppression of paternal gene expression will evolve (haplodiploidy, thelytoky), or other features of the life cycle will evolve to minimize the conflict (monogamy, inbreeding). Maternally transmitted cytoplasmic elements and maternally imprinted nuclear alleles have a shared interest in minimizing agonistic interactions between female siblings and may cooperate to exclude the paternal genome. Eusociality is the most dramatic expression of the conflict-reducing effects of

  19. Utilization of white potatoes in CELSS.

    PubMed

    Tibbitts, T W; Bennett, S M; Morrow, R C; Bula, R J

    1989-01-01

    Potatoes (Solanum tuberosum) have a strong potential as a useful crop species in a functioning CELSS. The cultivar Denali has produced 37.5 g m-2 d-1 when grown for 132 days with the first 40 days under a 12-h photoperiod and a light:dark temperature cycle of 20 degrees C:16 degrees C, and then 92 days under continuous irradiance and a temperature of 16 degrees C. Irradiance was at 725 micromoles m-2 s-1 PPF and carbon dioxide at 1000 micromoles mol-1. The dried tubers had 82% carbohydrates, 9% protein and 0.6% fat. Other studies have shown that carbon dioxide supplementation (1000 micromoles mol-1) is of significant benefit under 12-h irradiance but less benefit under 24 h irradiance. Irradiance cycles of 60 minutes light and 30 minutes dark caused a reduction of more than 50% in tuber weight compared to cycles of 16 h light and 8 h dark. A diurnal temperature change of 22 degrees C for the 12-h light period to 14 degrees C during the 12-h dark period gave increased yields of 30% and 10% for two separate cultivars, compared with plants grown under a constant 18 degrees C temperature. Cultivar screening under continuous irradiance and elevated temperatures (28 degrees C) for 8 weeks of growth indicated that the cvs Haig, Denali, Atlantic, Desiree and Rutt had the best potential for tolerance to these conditions. Harvesting of tubers from plants at weekly intervals, beginning at 8 weeks after planting, did not increase yield over a single final harvest. Spacing of plants on 0.055 centers produced greater yield per m2 than spacing at 0.11 or 0.22 m2. Plants maintained 0.33 meters apart (0.111 m2 per plant) in beds produced the same yields when separated by dividers in the root matrix as when no separation was made.

  20. Predictive Quantum Chemistry: A Step Toward ``Chemistry Without Test Tubes''

    NASA Astrophysics Data System (ADS)

    Perera, Ajith

    2007-12-01

    The merits of the claims made in two recent papers entitled "First generation of pentazole (HN5, pentazolic acid), the final azole, and a zinc pentazolate salt in solution: A new N-dearylation of 1-(p-methoxyphenyl) pyrazoles, a 2-(p-methoxyphenyl) tetrazole and application of the methodology to 1-(p-methoxyphenyl) pentazole" (R. N. Butler, J. C. Stephan and L. A. Burke, J. Chem. Commun. 2003, 1016-1017) and "First generation of the pentazolate anion is solution is far from over" (T. Schroer, R. Haiges, S. Schneider and K. O. Christe, Chem. Commun. 2005, 1607-1609) are verified by predictive quality theoretical methods. Knowing whether the CF3OH in HF solution undergoes protonation to form CF3[OH2]+ is critical to the success of the recently proposed synthetic route to form the prototype perfluorinated alcohol, CF3OH. Chirstie and co-workers first considered the 13C and 19F shielding constants to distinguish CF3OH and CF3[OH2]+, but it turns out that they both have similar chemical shifts. Furthermore, they noted that the computed 13C chemical shifts differ by 11 ppm from the measured ones and claimed that "These findings presented a dilemma because either experimental or the calculated shifts has to be seriously flawed and, therefore chemical shifts alone it was impossible to decide whether CF3OH in liquid HF is protonated or not". Instead of chemical shifts, they propose to use 13C-19F NMR spin-spin coupling constants and argue that the observed 20 Hz difference of 1J(13C-19F) to the increase in the covalent character upon protonation. The reported discrepancy in computed and measured chemical shifts is reexamined and the spin-spin coupling constants results are verified by the predicative-level calculations.

  1. Migration stopovers and the conservation of arctic-breeding Calidris sandpipers

    USGS Publications Warehouse

    Skagen, S.K.

    2006-01-01

    Long-distance migration, one of the most physically demanding events in the animal kingdom, is well developed in many species of Charadriidae and Scolopacidae. Some shorebirds renowned for their extraordinary long-distance migrations, notably American Golden-Plover (Pluvialis dominica), Red Knot (Calidris canutus rufa), and White-rumped Sandpiper (C. fuscicollis), travel as many as 15,000 km between southern South American wintering grounds and Canadian Arctic breeding areas. Migration strategies of shorebirds vary in many aspects. There are remarkable accounts of shorebirds, such as northbound Red Knots, that stage a few key sites for 2-3 weeks and lay on extensive body stores, then fly nonstop for distances of [greater than or equal to] 2,500 km (Harrington 2001, Piersma et al. 2005). Less well known are the examples of populations that refuel only briefly at stopover sites, disperse broadly on the landscape, and fly shorter distances between sites (Skagen 1997, Haig et al. 1998, Warnock et al. 1998). This latter pattern applies to many long-distance migrant shorebirds that cross the interior plains of North America during spring and fall migrations. For them, interior wetland complexes provide critical refueling resources along the direct routes between summering and wintering grounds (Skagen et al. 1999). In this issue of The Auk, Krapu et al. (2006) describe patterns and implications of fat deposition by Semipalmated Sandpipers (C. pusilla), White-rumped Sandpipers, and Bairda??s Sandpipers (C. bairdii) refueling during northward migration across the prairies of mid-continental North Americaa?|

  2. Mineralogy of Meteorite Groups

    NASA Technical Reports Server (NTRS)

    Rubin, Alan E.

    1997-01-01

    phases were formed by shock metamorphism. Martensite (a2-fe,Ni) has a distorted body-centered-cubic structure and formed by a shear transformation from taenite during shock reheating and rapid cooling. The C polymorphs diamond, lonsdaleite and chaoite formed by shock from graphite. Suessite formed in the North Haig ureilite by reduction of Fe and Si (possibly from olivine) via reaction with carbonaceous matrix material. Ringwoodite, the spinel form of (Mg,Fe)2Si04, and majorite, a polymorph of (Mg,Fe)Si03 with the garnet structure, formed inside shock veins in highly shocked ordinary chondrites. Secondary minerals in meteorite finds that formed during terrestrial weathering include oxides and hy-. droxides formed directly from metallic Fe-Ni by oxidation, phosphates formed by the alteration of schreibersite, and sulfates formed by alteration of troilite.

  3. Utilization of white potatoes in CELSS

    NASA Astrophysics Data System (ADS)

    Tibbitts, Theodore W.; Bennett, Susan M.; Morrow, Robert C.; Bula, Raymond J.

    Potatoes (Solanum tuberosum) have a strong potential as a useful crop species in a functioning CELSS. The cultivar Denali has produced 37.5 g m-2 d-1 when grown for 132 days with the first 40 days under a 12-h photoperiod and a light:dark temperature cycle of 20°C: 16°C, and then 92 days under continuous irradiance and a temperature of 16°C. Irradiance was at 725 μmol m-2 s-1 PPF and carbon dioxide at 1000 μmol mol-1. The dried tubers had 82% carbohydrates, 9% protein and 0.6% fat. Other studies have shown that carbon dioxide supplementation (1000 μmol mol-1) is of significant benefit under 12-h irradiance but less benefit under 24 h irradiance. Irradiance cycles of 60 minutes light and 30 minutes dark caused a reduction of more than 50% in tuber weight compared to cycles of 16 h light and 8 h dark. A diurnal temperature change of 22°C for the 12-h light period to 14°C during the 12-h dark period gave increased yields of 30% and 10% for two separate cultivars, compared with plants grown under a constant 18°C temperature. Cultivar screening under continuous irradiance and elevated temperatures (28°C) for 8 weeks of grown indicated that the cvs Haig, Denali, Atlantic, Desiree and Rutt had the best potential for tolerance to these conditions. Harvesting of tubers from plants at weekly intervals, beginning at 8 weeks after planting, did not increase yield over a single final harvest. Spacing of plants on 0.055 centers produced greater yield per m2 than spacing at 0.11 or 0.22 m2. Plants maintained 0.33 meters apart (0.111 m2 per plant) in beds produced the same yields when separated by dividers in the root matrix as when no separation was made.

  4. Foundations of Forensic Meteoritics

    NASA Astrophysics Data System (ADS)

    Treiman, A. H.

    1992-07-01

    It may be useful to know if a meteorite was found at the site where it fell. For instance, the polymict ureilites North Haig and Nilpena were found 1100 km apart, yet are petrologically identical [1]. Could this distance represent transport from a single strewn field, or does it represent distinct fall sites? A meteorite may contain sufficient clues to suggest some characteristics of its fall site. If these inferences are inconsistent with the find site, one may infer that the meteorite has been transported. It will likely be impossible to determine the exact fall site of a transported meteorite. Data relevant to a meteorite's fall site may be intrinsic to the meteorite, or acquired at the site. For instance, an intrinsic property is terrestrial residence age (from abundances of cosmogenic radioisotopes and their decay products); a meteorite's terrestrial residence age must be the same or less than that of the surface on which it fell. After falling, a meteorite may acquire characteristic telltales of terrestrial geological, geochemical, and biological processes. These telltale clues may include products of chemical weathering, adhering geological materials, biological organisms living (or once living) on the meteorite, and biological materials adhering to (but never living on) the meteorite. The effects of chemical weathering, present in all but the freshest finds, range from slight rusting to extensive decomposition and veining The ages of weathering materials and veins, as with terrestrial residence ages above, must be less than the age of the fall surface. The mineralogy and chemistry, elemental and isotopic, of weathering materials will differ according to the mineralogy and composition of the meteorite, and the mineralogy, geochemistry, hydrology, and climate of the fall site. Weathering materials may also vary as climate changes and may vary among the microenvironments associated with a meteorite on the Earth's surface. Geological materials (rock, sediment

  5. TASK 2.5.7 FIELD EXPERIMENTS TO EVALUATE COOL-COLORED ROOFING

    SciTech Connect

    Miller, William A; Cherry, Nigel J; Allen, Richard Lowell; Childs, Phillip W; Atchley, Jerald Allen; Ronnen, Levinson; Akbari, Hashem; Berhahl, Paul

    2010-03-01

    Aesthetically pleasing dark roofs can be formulated to reflect like a highly reflective white roof in the near infrared portion of the solar spectrum. New paint pigments increase the near infrared reflectance of exterior finishes by minimizing the absorption of near-infrared radiation (NIR). The boost in the NIR reflectance drops the surface temperatures of roofs and walls, which in turn reduces cooling-energy use and provides savings for the homeowner and relief for the utilities. In moderate and hot climates, a roof surface with high solar reflectance and high thermal emittance was shown by Akbari et al. (2004) and by Parker and Sherwin (1998) to reduce the exterior temperature and produce savings in comfort cooling. The new cool color pigments can potentially reduce emissions of carbon dioxide, which in turn reduces metropolitan heat buildup and urban smog. The pigments can also help conserve water resources otherwise used to clean and process fuel consumed by fossil-fuel driven power plants. Cool roofs also result in a lower ambient temperature that further decreases the need for air conditioning, retards smog formation, and improves thermal comfort. Parker, Sonne and Sherwin (2002) demonstrated that white barrel and white flat tiles reduced cooling energy consumption by 22% of the base load used by an adjacent and identical home having direct nailed dark shingles. Part of the savings was due to the reflectance of the white tiles; however, another part was due to the mass of the tile and to the venting occurring within the double batten installation. With, Cherry and Haig (2009) have studied the influence of the thermal mass and batten space ventilation and have found that, referenced to an asphalt shingle system, it can be equivalent to an additional 28 points of solar reflectivity. The double batten arrangement has wooden counter battens laid vertically (soffit-to-ridge) against the roof deck, and then the conventional battens are laid horizontally across the