Inventory of File nam.t00z.awip3d00.tm00.grib2

Science.gov Websites

Specific Humidity [kg/kg] 432 0-0.1 m below ground TSOIL analysis Soil Temperature Validation to deprecate [K] 433 0-0.1 m below ground SOILW analysis Volumetric Soil Moisture Content [Fraction] 434 0-0.1 m below ground SOILL analysis Liquid Volumetric Soil Moisture (non Frozen) [Proportion] 435 0.1-0.4 m

Inventory of File nam.t00z.awp24206.tm00.grib2

Science.gov Websites

TSOIL 6 hour fcst Soil Temperature Validation to deprecate [K] 034 0-0.1 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content [Fraction] 035 0-0.1 m below ground SOILL 6 hour fcst Liquid Volumetric Soil Moisture (non Frozen) [Proportion] 036 0.1-0.4 m below ground TSOIL 6 hour fcst Soil

Inventory of File sref_nmb.t03z.pgrb132.p1.f00.grib2

Science.gov Websites

TSOIL analysis Soil Temperature Validation to deprecate [K] 403 0-0.1 m below ground SOILW analysis Volumetric Soil Moisture Content [Fraction] 404 0.1-0.4 m below ground TSOIL analysis Soil Temperature Validation to deprecate [K] 405 0.1-0.4 m below ground SOILW analysis Volumetric Soil Moisture Content

Inventory of File sref_nmb.t03z.pgrb132.p1.f06.grib2

Science.gov Websites

6 hour fcst Soil Temperature Validation to deprecate [K] 403 0-0.1 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content [Fraction] 404 0.1-0.4 m below ground TSOIL 6 hour fcst Soil Temperature Validation to deprecate [K] 405 0.1-0.4 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content

Inventory of File sref_em.t03z.pgrb132.p1.f06.grib2

Science.gov Websites

6 hour fcst Soil Temperature Validation to deprecate [K] 402 0-0.1 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content [Fraction] 403 0.1-0.4 m below ground TSOIL 6 hour fcst Soil Temperature Validation to deprecate [K] 404 0.1-0.4 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content

Inventory of File sref_nmm.t03z.pgrb132.p1.f06.grib2

Science.gov Websites

6 hour fcst Soil Temperature Validation to deprecate [K] 403 0-0.1 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content [Fraction] 404 0.1-0.4 m below ground TSOIL 6 hour fcst Soil Temperature Validation to deprecate [K] 405 0.1-0.4 m below ground SOILW 6 hour fcst Volumetric Soil Moisture Content

Preparation and Analysis of RNA Crystals

NASA Technical Reports Server (NTRS)

Todd, Paul

2000-01-01

The crystallization of RiboNucleic Acids (RNA) was studied from the standpoint of mechanisms of crystal growth in three tasks: (1) preparation of high-quality crystals of oligonuclotides for X-ray diffraction, (2) finding pathways to the growth of high-quality crystals for X-ray diffraction and (3) investigation of mechanisms of action of inertial acceleration on crystal growth. In these tasks: (1) RNA crystals were prepared and studied by X-ray diffraction; (2) a pathway to high-quality crystals was discovered and characterized; a combination of kinetic and equilibrium factors could be optimized as described below; and (3) an interplay between purity and gravity was found in a combination of space and ground experiments with nucleic acids and proteins. Most significantly, the rate of concentration of precipitant and RNA can be controlled by membrane-based methods of water removal or by diffusion of multivalent cations across an interface stabilized by a membrane. Oligonucleotide solutions are electrokinetically stabilized colloids, and crystals can form by the controlled addition of multivalent cations.

Fertilization Increases Below-Ground Carbon Sequestration of Loblolly Pine Plantations

Treesearch

K.H. Johnsen; J.R. Butnor; C. Maier; R. Oren; R. Pangle; L. Samuelson; J. Seiler; S.E. McKeand; H.L. Allen

2001-01-01

The extent of fertilization of southern pine forests is increasing rapidly; industrial fertilization increased from 16,200 ha per year in 1988, to 344,250 ha in 1998. Fertilization increases stand productivity and can increase carbon (C) sequestration by: 1) increasing above-ground standing C; 2) increasing C stored in forest products; and 3) increasing below-ground...

THE EFFECT OF OZONE ON BELOW-GROUND CARBON ALLOCATION IN WHEAT

EPA Science Inventory

Short term 14CO2 pulse and chase experiments were conducted in order to investigate the effect ozone on below-ground carbon allocation in spring wheat seedlings (Triticum aestivumL. ?ANZA'). Wheat seedlings were grown in a sand-hydroponic system and exposed to either high ozone ...

Below-ground process responses to elevated CO2 and temperature: a discussion of observations, measurement methods, and models

Treesearch

Elise Pendall; Scott Bridgham; Paul J. Hanson; Bruce Hungate; David W. Kicklighter; Dale W. Johnson; Beverly E. Law; Yiqi Luo; J. Patrick Megonigal; Maria Olsrud; Michael G. Ryan; Shiqiang Wan

2004-01-01

Rising atmospheric CO2 and temperatures are probably altering ecosystem carbon cycling, causing both positive and negative feedbacks to climate. Below-ground processes play a key role in the global carbon (C) cycle because they regulate storage of large quantities of C, and are potentially very sensitive to direct and indirect effects of elevated...

Facilitation and inhibition: changes in plant nitrogen and secondary metabolites mediate interactions between above-ground and below-ground herbivores.

PubMed

Huang, Wei; Siemann, Evan; Yang, Xuefang; Wheeler, Gregory S; Ding, Jianqing

2013-09-22

To date, it remains unclear how herbivore-induced changes in plant primary and secondary metabolites impact above-ground and below-ground herbivore interactions. Here, we report effects of above-ground (adult) and below-ground (larval) feeding by Bikasha collaris on nitrogen and secondary chemicals in shoots and roots of Triadica sebifera to explain reciprocal above-ground and below-ground insect interactions. Plants increased root tannins with below-ground herbivory, but above-ground herbivory prevented this increase and larval survival doubled. Above-ground herbivory elevated root nitrogen, probably contributing to increased larval survival. However, plants increased foliar tannins with above-ground herbivory and below-ground herbivory amplified this increase, and adult survival decreased. As either foliar or root tannins increased, foliar flavonoids decreased, suggesting a trade-off between these chemicals. Together, these results show that plant chemicals mediate contrasting effects of conspecific larval and adult insects, whereas insects may take advantage of plant responses to facilitate their offspring performance, which may influence population dynamics.

Using simple environmental variables to estimate below-ground productivity in grasslands

USGS Publications Warehouse

Gill, R.A.; Kelly, R.H.; Parton, W.J.; Day, K.A.; Jackson, R.B.; Morgan, J.A.; Scurlock, J.M.O.; Tieszen, L.L.; Castle, J.V.; Ojima, D.S.; Zhang, X.S.

2002-01-01

In many temperate and annual grasslands, above-ground net primary productivity (NPP) can be estimated by measuring peak above-ground biomass. Estimates of below-ground net primary productivity and, consequently, total net primary productivity, are more difficult. We addressed one of the three main objectives of the Global Primary Productivity Data Initiative for grassland systems to develop simple models or algorithms to estimate missing components of total system NPP. Any estimate of below-ground NPP (BNPP) requires an accounting of total root biomass, the percentage of living biomass and annual turnover of live roots. We derived a relationship using above-ground peak biomass and mean annual temperature as predictors of below-ground biomass (r2 = 0.54; P = 0.01). The percentage of live material was 0.6, based on published values. We used three different functions to describe root turnover: constant, a direct function of above-ground biomass, or as a positive exponential relationship with mean annual temperature. We tested the various models against a large database of global grassland NPP and the constant turnover and direct function models were approximately equally descriptive (r2 = 0.31 and 0.37), while the exponential function had a stronger correlation with the measured values (r2 = 0.40) and had a better fit than the other two models at the productive end of the BNPP gradient. When applied to extensive data we assembled from two grassland sites with reliable estimates of total NPP, the direct function was most effective, especially at lower productivity sites. We provide some caveats for its use in systems that lie at the extremes of the grassland gradient and stress that there are large uncertainties associated with measured and modelled estimates of BNPP.

Facilitation and inhibition: changes in plant nitrogen and secondary metabolites mediate interactions between above-ground and below-ground herbivores

PubMed Central

Huang, Wei; Siemann, Evan; Yang, Xuefang; Wheeler, Gregory S.; Ding, Jianqing

2013-01-01

To date, it remains unclear how herbivore-induced changes in plant primary and secondary metabolites impact above-ground and below-ground herbivore interactions. Here, we report effects of above-ground (adult) and below-ground (larval) feeding by Bikasha collaris on nitrogen and secondary chemicals in shoots and roots of Triadica sebifera to explain reciprocal above-ground and below-ground insect interactions. Plants increased root tannins with below-ground herbivory, but above-ground herbivory prevented this increase and larval survival doubled. Above-ground herbivory elevated root nitrogen, probably contributing to increased larval survival. However, plants increased foliar tannins with above-ground herbivory and below-ground herbivory amplified this increase, and adult survival decreased. As either foliar or root tannins increased, foliar flavonoids decreased, suggesting a trade-off between these chemicals. Together, these results show that plant chemicals mediate contrasting effects of conspecific larval and adult insects, whereas insects may take advantage of plant responses to facilitate their offspring performance, which may influence population dynamics. PMID:23902902

Below-ground carbon transfer among Betula nana may increase with warming in Arctic tundra.

PubMed

Deslippe, Julie R; Simard, Suzanne W

2011-11-01

• Shrubs are expanding in Arctic tundra, but the role of mycorrhizal fungi in this process is unknown. We tested the hypothesis that mycorrhizal networks are involved in interplant carbon (C) transfer within a tundra plant community. • Here, we installed below-ground treatments to control for C transfer pathways and conducted a (13)CO(2)-pulse-chase labelling experiment to examine C transfer among and within plant species. • We showed that mycorrhizal networks exist in tundra, and facilitate below-ground transfer of C among Betula nana individuals, but not between or within the other tundra species examined. Total C transfer among conspecific B. nana pairs was 10.7 ± 2.4% of photosynthesis, with the majority of C transferred through rhizomes or root grafts (5.2 ± 5.3%) and mycorrhizal network pathways (4.1 ± 3.3%) and very little through soil pathways (1.4 ± 0.35%). • Below-ground C transfer was of sufficient magnitude to potentially alter plant interactions in Arctic tundra, increasing the competitive ability and mono-dominance of B. nana. C transfer was significantly positively related to ambient temperatures, suggesting that it may act as a positive feedback to ecosystem change as climate warms. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

High yielding biomass genotypes of willow (Salix spp.) show differences in below ground biomass allocation

PubMed Central

Cunniff, Jennifer; Purdy, Sarah J.; Barraclough, Tim J.P.; Castle, March; Maddison, Anne L.; Jones, Laurence E.; Shield, Ian F.; Gregory, Andrew S.; Karp, Angela

2015-01-01

Willows (Salix spp.) grown as short rotation coppice (SRC) are viewed as a sustainable source of biomass with a positive greenhouse gas (GHG) balance due to their potential to fix and accumulate carbon (C) below ground. However, exploiting this potential has been limited by the paucity of data available on below ground biomass allocation and the extent to which it varies between genotypes. Furthermore, it is likely that allocation can be altered considerably by environment. To investigate the role of genotype and environment on allocation, four willow genotypes were grown at two replicated field sites in southeast England and west Wales, UK. Above and below ground biomass was intensively measured over two two-year rotations. Significant genotypic differences in biomass allocation were identified, with below ground allocation differing by up to 10% between genotypes. Importantly, the genotype with the highest below ground biomass also had the highest above ground yield. Furthermore, leaf area was found to be a good predictor of below ground biomass. Growth environment significantly impacted allocation; the willow genotypes grown in west Wales had up to 94% more biomass below ground by the end of the second rotation. A single investigation into fine roots showed the same pattern with double the volume of fine roots present. This greater below ground allocation may be attributed primarily to higher wind speeds, plus differences in humidity and soil characteristics. These results demonstrate that the capacity exists to breed plants with both high yields and high potential for C accumulation. PMID:26339128

Below-ground herbivory in natural communities: a review emphasizing fossorial animals

USGS Publications Warehouse

Andersen, Douglas C.

1987-01-01

Roots, bulbs, corms, and other below-ground organs are almost universally present in communities containing vascular plants. A large and taxonomically diverse group of herbivores uses these below-ground plant parts as its sole or primary source of food. Important within this group are plant-parasitic nematodes and several fossorial taxa that affect plants through their soil-disturbing activities as well as by consuming plant tissue. The fossorial taxa are probably best exemplified by fossorial rodents, which are distributed on all continents except Australia. All other fossorial herbivores are insects. The impact of below-groud herbivory on individual plant fitness will depend upon the extent to which, and under what circumstances, the consumption of plant tissue disrupts one or more of the six functions of below-ground plant parts. Below-ground herbivory is probably more often chronic than acute. Indirect evidence suggests that plants have responded evolutionarily to herbivory by enhancing the functional capacities of below-ground organs, thus developing a degree of tolerance, and by producing compounds that serve as feeding deterrents. Many plant species respond to the removal of root tissues by increasing the growth rate of the remaining roots and initiating new roots. Soil movement and mixing by fossorial rodents infleuce the environment of other below-ground herbivores as well as that of plants and plant propagules. The relationships among the various groups of below-ground herbivores, and between below-ground herbivores and plants, are at best poorly known, yet they appear to have major roles in determining the structure and regulating the functioning of natural communities.

Low Cost Multi-Sensor Robot Laser Scanning System and its Accuracy Investigations for Indoor Mapping Application

NASA Astrophysics Data System (ADS)

Chen, C.; Zou, X.; Tian, M.; Li, J.; Wu, W.; Song, Y.; Dai, W.; Yang, B.

2017-11-01

In order to solve the automation of 3D indoor mapping task, a low cost multi-sensor robot laser scanning system is proposed in this paper. The multiple-sensor robot laser scanning system includes a panorama camera, a laser scanner, and an inertial measurement unit and etc., which are calibrated and synchronized together to achieve simultaneously collection of 3D indoor data. Experiments are undertaken in a typical indoor scene and the data generated by the proposed system are compared with ground truth data collected by a TLS scanner showing an accuracy of 99.2% below 0.25 meter, which explains the applicability and precision of the system in indoor mapping applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kennedy, R.P.; Kincaid, R.H.; Short, S.A.

This report presents the results of part of a two-task study on the engineering characterization of earthquake ground motion for nuclear power plant design. Task I of the study, which is presented in NUREG/CR-3805, Vol. 1, developed a basis for selecting design response spectra taking into account the characteristics of free-field ground motion found to be significant in causing structural damage. Task II incorporates additional considerations of effects of spatial variations of ground motions and soil-structure interaction on foundation motions and structural response. The results of Task II are presented in four parts: (1) effects of ground motion characteristics onmore » structural response of a typical PWR reactor building with localized nonlinearities and soil-structure interaction effects; (2) empirical data on spatial variations of earthquake ground motion; (3) soil-structure interaction effects on structural response; and (4) summary of conclusions and recommendations based on Tasks I and II studies. This report presents the results of the first part of Task II. The results of the other parts will be presented in NUREG/CR-3805, Vols. 3 to 5.« less

Transuranic Waste Program Framework Agreement - December Deliverable July 2012

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Patricia

Framework agreement deliverables are: (1) 'DOE/NNSA commits to complete removal of all non-cemented above-ground EM Legacy TRU and newly generated TRU currently-stored at Area G as of October 1, 2011, by no later than June 30, 2014. This inventory of above-ground TRU is defined as 3706 cubic meters of material.' (2) 'DOE commits to the complete removal of all newly generated TRU received in Area G during FY 2012 and 2013 by no later than December 31, 2014.' (3) 'Based on projected funding profiles, DOE/NNSA will develop by December 31, 2012, a schedule, including pacing milestones, for disposition of themore » below-ground TRU requiring retrieval at Area G.' Objectives are to: (1) restore the 'Core Team' to develop the December, 2012 deliverable; (2) obtain agreement on the strategy for below ground water disposition; and (3) establish timeline for completion of the deliverable. Below Grade Waste Strategy is to: (1) Perform an evaluation on below grade waste currently considered retrievable TRU; (2) Only commit to retrieve waste that must be retrieved; (3) Develop the Deliverable including Pacing Milestones based on planned commitments; (4) Align all Regulatory Documents for Consistency; and (5) answer these 3 primary questions, is the waste TRU; is the waste retrievable, can retrieval cause more harm than benefit?« less

Ab initio study of the ground state surface of Cu3

NASA Technical Reports Server (NTRS)

Langhoff, Stephen R.; Bauschlicher, Charles W., Jr.; Walch, Stephen P.; Laskowski, Bernard C.

1986-01-01

The ground state surface of the metallic trimer Cu3 is investigated theoretically. Relativistic and correlation effects are taken into account in ab initio computations, which are calibrated against analogous computations for the 1Sigma(g)+ state of Cu2; the results are presented in tables and analyzed. The Cu3 ground state is found to have a 2B2 C(2v) structure with angle greater than 60 deg, lying 59/cm below a 2A1 C(2v) geometry and 280/cm below the D(3h) equilateral geometry. These findings are shown to be in good agreement with the experimental measurements of Rohlfing and Valentini (1986) and their analysis (in terms of a Jahn-Teller distortion of 2E-prime equilateral-triangle geometry) by Truhlar et al. (1986).

The effect of sinusoidal rolling ground motion on lifting biomechanics.

PubMed

Ning, Xiaopeng; Mirka, Gary A

2010-12-01

The objective of this study was to quantify the effects of ground surface motion on the biomechanical responses of a person performing a lifting task. A boat motion simulator (BMS) was built to provide a sinusoidal ground motion (simultaneous vertical linear translation and a roll angular displacement) that simulates the deck motion on a small fishing boat. Sixteen participants performed lifting, lowering and static holding tasks under conditions of two levels of mass (5 and 10 kg) and five ground moving conditions. Each ground moving condition was specified by its ground angular displacement and instantaneous vertical acceleration: A): +6°, -0.54 m/s(2); B): +3°, -0.27 m/s(2); C): 0°, 0m/s(2); D): -3°, 0.27 m/s(2); and E): -6°, 0.54 m/s(2). As they performed these tasks, trunk kinematics were captured using the lumbar motion monitor and trunk muscle activities were evaluated through surface electromyography. The results showed that peak sagittal plane angular acceleration was significantly higher in Condition A than in Conditions C, D and E (698°/s(2) vs. 612-617°/s(2)) while peak sagittal plane angular deceleration during lowering was significantly higher in moving conditions (conditions A and E) than in the stationary condition C (538-542°/s(2) vs. 487°/s(2)). The EMG results indicate that the boat motions tend to amplify the effects of the slant of the lifting surface and the external oblique musculature plays an important role in stabilizing the torso during these dynamic lifting tasks. Copyright © 2010 Elsevier Ltd. All rights reserved.

Inventory of File nam.t00z.hawaiinest.hiresf00.tm00.gr

Science.gov Websites

m below ground TSOIL analysis Soil Temperature Validation to deprecate [K] 589 0-0.1 m below ground SOILW analysis Volumetric Soil Moisture Content [Fraction] 590 0-0.1 m below ground SOILL analysis Liquid Volumetric Soil Moisture (non Frozen) [Proportion] 591 0.1-0.4 m below ground TSOIL analysis Soil

Inventory of File nam.t00z.firewxnest.hiresf00.tm00.gr

Science.gov Websites

m below ground TSOIL analysis Soil Temperature Validation to deprecate [K] 589 0-0.1 m below ground SOILW analysis Volumetric Soil Moisture Content [Fraction] 590 0-0.1 m below ground SOILL analysis Liquid Volumetric Soil Moisture (non Frozen) [Proportion] 591 0.1-0.4 m below ground TSOIL analysis Soil

Inventory of File nam.t00z.conusnest.hiresf00.tm00.gri

Science.gov Websites

m below ground TSOIL analysis Soil Temperature Validation to deprecate [K] 589 0-0.1 m below ground SOILW analysis Volumetric Soil Moisture Content [Fraction] 590 0-0.1 m below ground SOILL analysis Liquid Volumetric Soil Moisture (non Frozen) [Proportion] 591 0.1-0.4 m below ground TSOIL analysis Soil

Inventory of File nam.t00z.alaskanest.hiresf00.tm00.gr

Science.gov Websites

m below ground TSOIL analysis Soil Temperature Validation to deprecate [K] 589 0-0.1 m below ground SOILW analysis Volumetric Soil Moisture Content [Fraction] 590 0-0.1 m below ground SOILL analysis Liquid Volumetric Soil Moisture (non Frozen) [Proportion] 591 0.1-0.4 m below ground TSOIL analysis Soil

Physiological girdling of pine trees via phloem chilling: proof of concept

Treesearch

Kurt Johnsen; Chris Maier; Felipe Sanchez; Peter Anderson; John Butnor; Richard Waring; Sune Linder

2007-01-01

Quantifying below-ground carbon (C) allocation is particularly difficult as methods usually disturb the root– mycorrhizal–soil continuum. We reduced C allocation below ground of loblolly pine trees by: (1) physically girdling trees and (2) physiologically girdling pine trees by chilling the phloem. Chilling reduced cambium temperatures by approximately 18 °C. Both...

Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

DOE PAGES

Zhao, Z. Y.; Calder, S.; Aczel, A. A.; ...

2016-04-25

The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Z. Y.; Calder, S.; Aczel, A. A.

The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

Molecular study of worldwide distribution and diversity of soil animals

PubMed Central

Wu, Tiehang; Ayres, Edward; Bardgett, Richard D.; Wall, Diana H.; Garey, James R.

2011-01-01

The global distribution of soil animals and the relationship of below-ground biodiversity to above-ground biodiversity are not well understood. We examined 17,516 environmental 18S rRNA gene sequences representing 20 phyla of soil animals sampled from 11 locations covering a range of biomes and latitudes around the world. No globally cosmopolitan taxa were found and only 14 of 2,259 operational taxonomic units (OTUs) found were common to four or more locations. Half of those were circumpolar and may reflect higher connectivity among circumpolar locations compared with other locations in the study. Even when OTU assembly criteria were relaxed to approximate the family taxonomic level, only 34 OTUs were common to four or more locations. A comparison of our diversity and community structure data to environmental factors suggests that below-ground animal diversity may be inversely related to above-ground biodiversity. Our data suggest that greater soil inorganic N and lower pH could explain the low below-ground biodiversity found at locations of high above-ground biodiversity. Our locations could also be characterized as being dominated by microarthropods or dominated by nematodes. Locations dominated by arthropods were primarily forests with lower soil pH, root biomass, mean annual temperature, low soil inorganic N and higher C:N, litter and moisture compared with nematode-dominated locations, which were mostly grasslands. Overall, our data indicate that small soil animals have distinct biogeographical distributions and provide unique evidence of the link between above-ground and below-ground biodiversity at a global scale. PMID:22006309

Is the scaling relationship between carbohydrate storage and leaf biomass in meadow plants affected by the disturbance regime?

PubMed

Klimešová, Jitka; Janecek, Štepán; Bartušková, Alena; Bartoš, Michael; Altman, Jan; Doležal, Jirí; Lanta, Vojtech; Latzel, Vít

2017-11-28

Below-ground carbohydrate storage is considered an adaptation of plants aimed at regeneration after disturbance. A theoretical model by Iwasa and Kubo was empirically tested which predicted (1) that storage of carbohydrates scales allometrically with leaf biomass and (2) when the disturbance regime is relaxed, the ratio of storage to leaf biomass increases, as carbohydrates are not depleted by disturbance. These ideas were tested on nine herbaceous species from a temperate meadow and the disturbance regime was manipulated to create recently abandoned and mown plots. Just before mowing in June and at the end of the season in October, plants with below-ground organs were sampled. The material was used to assess the pool of total non-structural carbohydrates and leaf biomass. In half of the cases, a mostly isometric relationship between below-ground carbohydrate storage and leaf biomass in meadow plants was found. The ratio of below-ground carbohydrate storage to leaf biomass did not change when the disturbance regime was less intensive than that for which the plants were adapted. These findings (isometric scaling relationship between below-ground carbohydrate storage and leaf biomass; no effect of a relaxed disturbance regime) imply that storage in herbs is probably governed by factors other than just the disturbance regime applied once in a growing season. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Evidence that acidification-induced declines in plant diversity and productivity are mediated by changes in below-ground communities and soil properties in a semi-arid steppe

USGS Publications Warehouse

Chen, Dima; Lan, Zhichun; Bai, Xue; Grace, James B.; Bai, Yongfei

2013-01-01

Synthesis. Our results suggest that the below-ground microbial and nematode communities are more sensitive to soil acidification than the plant communities are, and further that soil acidification–induced changes in plants are mediated by changes in below-ground communities and soil nutrients. These findings improve our understanding of the links between below- and above-ground communities in the Inner Mongolia grassland, especially in the context of anthropogenic acid enrichment.

Summary of hydrologic data collected during 1975 in Dade County, Florida

USGS Publications Warehouse

Hull, John E.; Beaven, T.R.

1977-01-01

During the 1975 calendar year rainfall in Dade County, Fla., was 14.89 inches below the long-term average (57.17 in.). Ground-water levels ranged from 0.1 foot above to 1.1 feet below average. The highest and lowest ground-water levels for the year were both 1 foot below their long-term averages. In the Hialeah-Miami Springs area, ground-water levels in wells near the centers of the heaviest pumping ranged from 9.8 to 11.2 feet below mean sea level and in the Southwest well field area, ground-water levels near the centers of pumping ranged from 3.5 feet above to 3.4 feet below mean sea level. The combined average daily discharge from eight major streams and canals that flow into Biscayne Bay was 1,014 cubic feet per second (cfs), 124 cfs above the combined average daily flow for the 1974 water year. The combined average daily flow through the Tamiami Canal outlets was 568 cfs, 202 cfs below that of the 1974 water year. The position of the salt front in 1975 in the coastal part of the Biscayne aquifer was about the same as in 1974 except at Miami International Airport and Homestead Air Force Base where the salt front had encroached farther inland. (Woodard-USGS)

Impacts of mute swans (Cygnus olor) on submerged aquatic vegetation in Illinois River Valley backwaters

USGS Publications Warehouse

Stafford, Joshua D.; Michael W. Eichholz,; Adam C. Phillips,

2012-01-01

Wetland loss in North America has been considerable and well documented, and the establishment of exotic species in remaining wetlands can further reduce their ability to support native flora and fauna. In the Chesapeake Bay and Great Lakes ecosystems, exotic mute swans (Cygnus olor) have been found to negatively impact wetlands through degradation of submerged aquatic vegetation (SAV) communities. Mute swan populations have expanded into many areas of mid-continental North America outside the Great Lakes ecosystem, but the environmental impact of these populations is not well known. Mid-continental wetlands in North America differ in physical characteristics (e.g., size, depth, and permanency) and aquatic vegetation species composition compared to wetlands in other areas where mute swans have been studied and, thus, may be more or less susceptible to degradation from swan herbivory. To investigate the impact of mute swan herbivory on SAV communities in mid-continent wetlands, we used exclosures to prevent swans from foraging in 2 wetland complexes in central Illinois. Above-ground biomass of vegetation did not differ between exclosures and controls; however, mean below-ground biomass was greater in exclosures (52.0 g/m2, SE = 6.0) than in controls (34.4 g/m2 SE = 4.0). Thus, although swan densities were lower in our study region compared to that of previous studies, we observed potentially detrimental impacts of swan herbivory on below-ground biomass of SAV. Our results indicate that both above-ground and below-ground impacts of herbivory should be monitored, and below-ground biomass may be most sensitive to swan foraging.

A Critical Survey of Optimization Models for Tactical and Strategic Aspects of Air Traffic Flow Management

NASA Technical Reports Server (NTRS)

Bertsimas, Dimitris; Odoni, Amedeo

1997-01-01

This document presents a critical review of the principal existing optimization models that have been applied to Air Traffic Flow Management (TFM). Emphasis will be placed on two problems, the Generalized Tactical Flow Management Problem (GTFMP) and the Ground Holding Problem (GHP), as well as on some of their variations. To perform this task, we have carried out an extensive literature review that has covered more than 40 references, most of them very recent. Based on the review of this emerging field our objectives were to: (i) identify the best available models; (ii) describe typical contexts for applications of the models; (iii) provide illustrative model formulations; and (iv) identify the methodologies that can be used to solve the models. We shall begin our presentation below by providing a brief context for the models that we are reviewing. In Section 3 we shall offer a taxonomy and identify four classes of models for review. In Sections 4, 5, and 6 we shall then review, respectively, models for the Single-Airport Ground Holding Problem, the Generalized Tactical FM P and the Multi-Airport Ground Holding Problem (for the definition of these problems see Section 3 below). In each section, we identify the best available models and discuss briefly their computational performance and applications, if any, to date. Section 7 summarizes our conclusions about the state of the art.

Arctic Oases? - River Aufeis Maintain Perennial Groundwater Habitat in the Arctic

NASA Astrophysics Data System (ADS)

Huryn, A. D.; Gooseff, M. N.; Briggs, M. A.; Terry, N.; Kendrick, M.; Hendrickson, P. J.; Grunewald, E. D.

2017-12-01

Aufeis are massive accumulations of ice found along many arctic rivers, with aufeis on some Alaskan rivers covering 20+ km2 and attaining thicknesses of 5+ m. Although aufeis are prominent landscape features, understanding of their ecology is poor. We propose that aufeis function as summer oases by providing meltwater and nutrients to downstream habitats and winter oases due to insulating layers of ice that maintain below-ground freshwater habitat that would otherwise be frozen in regions of continuous permafrost. To gain information about the ecological roles of aufeis, we installed 50 1-m deep wells in a 1.5 km2aufeis field along the Kuparuk River, an arctic tundra river in Alaska. We assessed the predictions that aufeis provide perennially-unfrozen, below-ground habitat for a specialized invertebrate community while functioning as hot spots for nutrient regeneration. Surface geophysical measurements made during the time of maximum ice thickness in 2017 indicated most of the Kuparuk feature was underlain by several meters of shallow frozen cobbles that were further underlain by a 10 m thick+ zone of thawed material. Ground penetrating radar and surface nuclear magnetic resonance data indicated several spatially-discrete thawed preferential flow zones through the shallow frozen sediment layer that may result from groundwater upwelling observed flowing through fractures in the icepack. Freshwater invertebrates sampled from the wells represent a rich community consisting of flatworms, annelids, copepods, ostracods, chironomids (Krenosmittia, Trichotanypus) and stoneflies. Although the potential for below-ground NH4+ and NO3-regeneration was indicated, analyses were complicated bya surprisingly strong and dynamic coupling of surface and below-ground water.

Field Variability of Invading Populations of Spartina densiflora Brong. in Different Habitats of the Odiel Marshes (SW Spain)

NASA Astrophysics Data System (ADS)

Nieva, F. J. J.; Díaz-Espejo, A.; Castellanos, E. M.; Figueroa, M. E.

2001-04-01

Spartina densiflora is a species of South American origin that has invaded the marshes of the Gulf of Cádiz, in many of which it has become the most abundant plant. This work studies six populations of S. densiflora representative of the physiographic positions most commonly occupied by the species. The aspects considered are redox potential, conductivity and pH of the sediment, below- and above-ground biomass, stem density, rates of flowering and production of vegetative propagules. Eh and conductivity values vary greatly, responding to differences in tidal effect. The below-ground biomass (in particular, live rhizomes) is accumulated mostly in the first centimetres of the soil; mean values of total below-ground biomass are between 6961 and 30 696 g DW m -2. Above-ground biomass levels for the populations ranges between 419 and 15 251 g DW m -2. The stem density within the tussocks is high, between 3985 and 10 513 stems m -2, with higher percentages of live stems on low and brackish marshes compared with those on higher topographic levels. This accumulation of dead and live intratussock biomass is important for the ability to exclude competitors. The flowering rates vary depending on topographic position, with maximum values being recorded in the low marsh (37·6%) and minima in the high marsh (0·1 to 0·3%). Besides the production of ramets from below-ground rhizomes (common to all species of the genus), S. densiflora presents another mode of asexual reproduction, in which extravaginal tillers are originated from the nodes of senescent ramets; populations on the higher levels of the marshes present higher densities of these propagules, with a negative correlation between rate of flowering and rate of propagule production. Nevertheless, the contribution of these propagules to the total stem population is very small. Our results show a high tolerance of S. densiflora to different environmental factors, an intense occupation of the available below-ground and above-ground space, and the capacity of sexual reproduction and of producing stems that sprout directly from the upper part of the canopy of S. densiflora, aspects that help to explain the ecological success of this species in the marshes of the Gulf of Cádiz.

Analysis of Space Shuttle Ground Support System Fault Detection, Isolation, and Recovery Processes and Resources

NASA Technical Reports Server (NTRS)

Gross, Anthony R.; Gerald-Yamasaki, Michael; Trent, Robert P.

2009-01-01

As part of the FDIR (Fault Detection, Isolation, and Recovery) Project for the Constellation Program, a task was designed within the context of the Constellation Program FDIR project called the Legacy Benchmarking Task to document as accurately as possible the FDIR processes and resources that were used by the Space Shuttle ground support equipment (GSE) during the Shuttle flight program. These results served as a comparison with results obtained from the new FDIR capability. The task team assessed Shuttle and EELV (Evolved Expendable Launch Vehicle) historical data for GSE-related launch delays to identify expected benefits and impact. This analysis included a study of complex fault isolation situations that required a lengthy troubleshooting process. Specifically, four elements of that system were considered: LH2 (liquid hydrogen), LO2 (liquid oxygen), hydraulic test, and ground special power.

48 CFR 237.170-2 - Approval requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-2 Approval requirements. (a) Acquisition of services through a contract or task order that is not performance based. (1) For acquisitions at or below $85.5 million, obtain the approval of the official... the senior procurement executive. (b) Acquisition of services through use of a contract or task order...

Ground State of Quasi-One Dimensional Competing Spin Chain Cs2Cu2Mo3O12 at zero and Finite Fields

NASA Astrophysics Data System (ADS)

Matsui, Kazuki; Goto, Takayuki; Angel, Julia; Watanabe, Isao; Sasaki, Takahiko; Hase, Masashi

The ground state of competing-spin-chain Cs2Cu2Mo3O12 with the ferromagnetic exchange interaction J1 = -93 K on nearest-neighboring spins and the antiferromagnetic one J2 = +33 K on next-nearest-neighboring spins was investigated by ZF/LF-μSR and 133Cs-NMR in the 3He temperature range. The zero-field μSR relaxation rate λ shows a significant increase below 1.85 K, suggesting the existence of magnetic order, which is consistent with the recent report on the specific heat. However, LF decoupling data at the lowest temperature 0.3 K indicate that the spins fluctuate dynamically, suggesting that the system is in a quasi-static ordered state under zero field. This idea is further supported by the fact that the broadening in NMR spectra below TN is weakened at low field below 2 T.

Modifying a Commercial Centrifuge to Reduce Electromagnetic Interference and Evaluating Functionality of Ultrasound Equipment

NASA Technical Reports Server (NTRS)

Greening, Gage J.

2016-01-01

The Project Management and Engineering Branch (SF4) supports the Human Health and Performance Directorate (HH&P) and is responsible for developing and supporting human systems hardware for the International Space Station (ISS). When a principal investigator's (PI) medical research project on the ISS is accepted, SF4 develops the necessary hardware and software to transport to the ISS. The two projects I primarily worked on were the centrifuge and ultrasound projects. Centrifuge: One concern with spacecraft such as the ISS is electromagnetic interference (EMI) from onboard equipment, typically from radio waves (frequencies of 3 kHz to 300 GHz), which can negatively affect nearby circuitry. Standard commercial centrifuges produce EMI above safety limits, so my task was to help reduce EMI production from this equipment. Two centrifuges were tested: one unmodified as a control and one modified. To reduce EMI below safety limits, one centrifuge was modified to become a Faraday shield, in which significant electrical contact was made between all regions of the centrifuge housing. This included removing non-conductive paint, applying conductive fabric to the lid and foam sealer, adding a 10,000 µF decoupling capacitor across the power supply, and adding copper adhesive-mount gaskets to the housing interior. EMI testing of both centrifuges was performed in the EMI/EMC Control Test and Measurement Facility. EMI for both centrifuges was below safety limits for frequencies between 10 MHz and 15 GHz (pass); however, between 14 kHz and 10 MHz, EMI for the unmodified centrifuge exceeded safety limits (fail) as expected. Alternatively, for the modified centrifuge with the Faraday shield, EMI was below the safely limit of 55 dBµV/m for electromagnetic frequencies between 14 kHz and 10 MHz. This result indicates our modifications were successful. The successful EMI test allowed us to communicate with the vendor what modifications they needed to make to their commercial unit to meet our specifications and to understand what needs to be done in lab to the new centrifuge. Our modifications will provide a standard for readying centrifuges for future missions. Once the new modified centrifuge arrives by the vendor, it will need to undergo EMI testing again for validation. The centrifuge is also in the process of compatibility testing with a custom stowage drawer, which is an ongoing project in SF4. Both of these items will be payloads on future missions to the ISS for various research purposes. Ultrasound: ISS currently has an onboard ultrasound (Ultrasound 2 system) for research and medical purposes. Every piece of medical flight hardware has an equivalent ground-unit so instrumentation can be routinely evaluated and transported to the ISS if necessary. The ground-unit ultrasound equipment must be evaluated every six months using a task performance sheet (TPS). A TPS is a document, written by the appropriate scientists and engineers, which describes how to run equipment and is written in such a way that astronauts with unspecialized training can follow the tasks. I was responsible for performing six TPSs on a combination of three ultrasounds and two video power converters (VPCs). Performing a TPS involves checking out and computationally documenting each piece of equipment removed from storage locations, setting up hardware and software, performing tasks to verify functionality, returning equipment, and logging items back into the computerized system. My work revealed all ground-unit ultrasounds were functioning properly. Because of proper function, a discrepancy report (DR) did not have to be opened. The TPS was then passed along to the Quality Engineering (QE) for review and ultimately given to Quality Assurance (QA). Other projects: In addition to my main projects, I participated in other tasks including troubleshooting an EEG headband, volunteering for an ultrasound training research study, and conformal coating printed circuit boards. My internship at SF4 has helped me understand how space systems hardware development for the ISS fits into NASA's mission and vision.

Below-ground chemical ecology and IPM

USDA-ARS?s Scientific Manuscript database

The phasing out of methyl bromide as a soil fumigant has led to a need for new technologies to manage below-ground plant pests and a sustainable approach would be to utilize semiochemicals comparable to above-ground IPM. Soil-dwelling beneficial entomopathogenic (EPNs) (Steinernema spp. and Heteror...

The Unilateral Below Elbow Test: a function test for children with unilateral congenital below elbow deficiency.

PubMed

Bagley, Anita M; Molitor, Fred; Wagner, Lisa V; Tomhave, Wendy; James, Michelle A

2006-07-01

The Unilateral Below Elbow Test (UBET) was developed to evaluate function in bimanual activities for both the prosthesis wearer and non-wearer. Nine tasks were chosen for each of four age-specific categories defined by development stages of hand function (2-4y, 5-7y, 8-10y, and 11-21y). Two scales, Completion of Task and Method of Use, were designed to rate performance. To measure reliability, four occupational therapists scored samples of videotaped UBET performances. For Completion of Task, an interval scale, agreement in scoring was measured with interclass correlation coefficients (ICC; n=9; five females, four males). For Method of Use, a nominal scale, chance-adjusted association was calculated with Cohen's kappa coefficients (interobserver n=198; 111 females, 87 males; intraobserver n=93; 56 females, 37 males). For Completion of Task, the average ICC was 0.87 for the prosthesis-on condition, and 0.85 for the prosthesis-off condition. ICCs exceeded 0.80 for eight out of nine tasks for the two older age groups, but for only five out of nine tasks in the younger age groups. Higher inter- and intraobserver kappa coefficients for Method of Use resulted when scoring children with their prostheses on versus off. The oldest age group had lower kappa values than the other three groups. The UBET is recommended for the functional evaluation of Completion of Task in children with unilateral congenital below elbow deficiency with and without their prostheses. Method of Use scoring can evaluate individuals for directed therapy interventions or prosthetic training.

The effects of 2 landing techniques on knee kinematics, kinetics, and performance during stop-jump and side-cutting tasks.

PubMed

Dai, Boyi; Garrett, William E; Gross, Michael T; Padua, Darin A; Queen, Robin M; Yu, Bing

2015-02-01

Anterior cruciate ligament injuries (ACL) commonly occur during jump landing and cutting tasks. Attempts to land softly and land with greater knee flexion are associated with decreased ACL loading. However, their effects on performance are unclear. Attempts to land softly will decrease peak posterior ground-reaction force (PPGRF) and knee extension moment at PPGRF compared with a natural landing during stop-jump and side-cutting tasks. Attempts to land with greater knee flexion at initial ground contact will increase knee flexion at PPGRF compared with a natural landing during both tasks. In addition, both landing techniques will increase stance time and lower extremity mechanical work as well as decrease jump height and movement speed compared with a natural landing during both tasks. Controlled laboratory study. A total of 18 male and 18 female recreational athletes participated in the study. Three-dimensional kinematic and kinetic data were collected during stop-jump and side-cutting tasks under 3 conditions: natural landing, soft landing, and landing with greater knee flexion at initial ground contact. Attempts to land softly decreased PPGRF and knee extension moment at PPGRF compared with a natural landing during stop-jump tasks. Attempts to land softly decreased PPGRF compared with a natural landing during side-cutting tasks. Attempts to land with greater knee flexion at initial ground contact increased knee flexion angle at PPGRF compared with a natural landing during both stop-jump and side-cutting tasks. Attempts to land softly and land with greater knee flexion at initial ground contact increased stance time and lower extremity mechanical work, as well as decreased jump height and movement speed during both stop-jump and side-cutting tasks. Although landing softly and landing with greater knee flexion at initial ground contact may reduce ACL loading during stop-jump and side-cutting tasks, the performance of these tasks decreased, as indicated by increased stance time and mechanical work as well as decreased jump height and movement speed. Training effects tested in laboratory environments with the focus on reducing ACL loading may be reduced in actual competition environments when the focus is on athlete performance. The effects of training programs for ACL injury prevention on lower extremity biomechanics in athletic tasks may need to be evaluated in laboratories as well as in actual competitions. © 2014 The Author(s).

FAA UAS Center of Excellence task A4: UAS ground collision severity evaluation, revision 2.

DOT National Transportation Integrated Search

2017-01-01

The UAS Ground Collision Severity Evaluation Final Report documents the UAS platform characteristics related to the severity of UAS ground collision based upon the literature search of over 300 publications from the automotive industry, consumer batt...

Final Harvest of Above-Ground Biomass and Allometric Analysis of the Aspen FACE Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mark E. Kubiske

The Aspen FACE experiment, located at the US Forest Service Harshaw Research Facility in Oneida County, Wisconsin, exposes the intact canopies of model trembling aspen forests to increased concentrations of atmospheric CO2 and O3. The first full year of treatments was 1998 and final year of elevated CO2 and O3 treatments is scheduled for 2009. This proposal is to conduct an intensive, analytical harvest of the above-ground parts of 24 trees from each of the 12, 30 m diameter treatment plots (total of 288 trees) during June, July & August 2009. This above-ground harvest will be carefully coordinated with themore » below-ground harvest proposed by D.F. Karnosky et al. (2008 proposal to DOE). We propose to dissect harvested trees according to annual height growth increment and organ (main stem, branch orders, and leaves) for calculation of above-ground biomass production and allometric comparisons among aspen clones, species, and treatments. Additionally, we will collect fine root samples for DNA fingerprinting to quantify biomass production of individual aspen clones. This work will produce a thorough characterization of above-ground tree and stand growth and allocation above ground, and, in conjunction with the below ground harvest, total tree and stand biomass production, allocation, and allometry.« less

Geochemical evolution of acidic ground water at a reclaimed surface coal mine in western Pennsylvania

USGS Publications Warehouse

Cravotta,, Charles A.

1991-01-01

Concentrations of dissolved sulfate and acidity in ground water increase downflow in mine spoil and underlying bedrock at a reclaimed surface coal mine in the bituminous field of western Pennsylvania. Elevated dissolved sulfate and negligible oxygen in ground water from bedrock about 100 feet below the water table suggest that pyritic sulfur is oxidized below the water table, in a system closed to oxygen. Geochemical models for the oxidation of pyrite (FeS2) and production of sulfate (SO42-) and acid (H+) are presented to explain the potential role of oxygen (O2) and ferric iron (Fe3+) as oxidants. Oxidation of pyrite by O2 and Fe3+ can occur under oxic conditions above the water table, whereas oxidation by Fe3+ also can occur under anoxic conditions below the water table. The hydrated ferric-sulfate minerals roemerite [Fe2+Fe43+(SO4)4·14H2O], copiapite [Fe2+Fe43+(SO4)6(OH)2·20H20], and coquimbite [Fe2(SO4)3·9H2O] were identified with FeS2 in coal samples, and form on the oxidizing surface of pyrite in an oxic system above the water table. These soluble ferric-sulfate 11 salts11 can dissolve with recharge waters or a rising water table releasing Fe3+, SO42-. and H+, which can be transported along closed-system ground-water flow paths to pyrite reaction sites where O2 may be absent. The Fe3+ transported to these sites can oxidize pyritic sulfur. The computer programs WATEQ4F and NEWBAL were used to compute chemical speciation and mass transfer, respectively, considering mineral dissolution and precipitation reactions plus mixing of waters from different upflow zones. Alternative mass-balance models indicate that (a) extremely large quantities of O2, over 100 times its aqueous solubility, can generate the observed concentrations of dissolved SO42- from FeS2, or (b) under anoxic conditions, Fe3+ from dissolved ferric-sulfate minerals can oxidize FeS2 along closed-system ground-water flow paths. In a system open to O2, such as in the unsaturated zone, the aqueous solubility of O2 is not limiting, and oxidation of pyrite by O2 and Fe3+ accounts for most SO42- and Fe2+ observed in acidic ground water. However, in a system closed to O2, such as in the saturated zone, O2 solubility is limiting; hence, ferric oxidation of pyrite is a reasonable explanation for the observed elevated SO42- with increasing depth below the water table.

Force Control Is Related to Low-Frequency Oscillations in Force and Surface EMG

PubMed Central

Moon, Hwasil; Kim, Changki; Kwon, Minhyuk; Chen, Yen Ting; Onushko, Tanya; Lodha, Neha; Christou, Evangelos A.

2014-01-01

Force variability during constant force tasks is directly related to oscillations below 0.5 Hz in force. However, it is unknown whether such oscillations exist in muscle activity. The purpose of this paper, therefore, was to determine whether oscillations below 0.5 Hz in force are evident in the activation of muscle. Fourteen young adults (21.07±2.76 years, 7 women) performed constant isometric force tasks at 5% and 30% MVC by abducting the left index finger. We recorded the force output from the index finger and surface EMG from the first dorsal interosseous (FDI) muscle and quantified the following outcomes: 1) variability of force using the SD of force; 2) power spectrum of force below 2 Hz; 3) EMG bursts; 4) power spectrum of EMG bursts below 2 Hz; and 5) power spectrum of the interference EMG from 10–300 Hz. The SD of force increased significantly from 5 to 30% MVC and this increase was significantly related to the increase in force oscillations below 0.5 Hz (R 2 = 0.82). For both force levels, the power spectrum for force and EMG burst was similar and contained most of the power from 0–0.5 Hz. Force and EMG burst oscillations below 0.5 Hz were highly coherent (coherence = 0.68). The increase in force oscillations below 0.5 Hz from 5 to 30% MVC was related to an increase in EMG burst oscillations below 0.5 Hz (R 2 = 0.51). Finally, there was a strong association between the increase in EMG burst oscillations below 0.5 Hz and the interference EMG from 35–60 Hz (R 2 = 0.95). In conclusion, this finding demonstrates that bursting of the EMG signal contains low-frequency oscillations below 0.5 Hz, which are associated with oscillations in force below 0.5 Hz. PMID:25372038

Microgravity

NASA Image and Video Library

2001-01-24

Typical metal sample that was processed by TEMPUS (Tiegelfreies Elektromagnetisches Prozessieren Unter Schwerelosigkeit), an electromagnetic levitation facility developed by German researchers and flown on the IML-2 and MSL-1 and 1R Spacelab missions. Electromagnetic levitation is used commonly in ground-based experiments to melt and then cool metallic melts below their freezing points without solidification occurring. Sample size is limited in ground-based experiments. Research with TEMPUS aboard Spacelab allowed scientists to study the viscosity, surface tension, and other properties of several metals and alloys while undercooled (i.e., cooled below their normal solidification points). The sample is about 1 cm (2/5 inch) in diameter.

Theoretical Prediction of Vibrational Circular Dichroism Spectra

DTIC Science & Technology

1990-01-01

Chabalowski U.S. ARMY BALLISTIC RESEARCH LABORATORY January 1990 DTIC ELECTESMAR 6U99 CHEMICAL COMMAN4D Aberden Proving Ground . MeMand 21010-5423 IDWPM...TASK [WORK UNIT ELEMENT NO. NO.11 46 2 6 2 2 NO. A5531 ACCESSION NO. Aberdeen Proving Ground , MD 21010-5423 IC4648061 D020 1 11. TITLE (Include...Engineering Center ATITN: SDCCR-RSP-C Aberdeen Proving Ground , MD 21010-5423 U.S. Army Ballistic Research Laboratory Aberdeen Proving Ground , MD

Infrared Imagery of Shuttle (IRIS). Task 1

NASA Technical Reports Server (NTRS)

Chocol, C. J.

1977-01-01

Assessment of available IR sensor technology showed that the four aerothermodynamic conditions of interest during the entry trajectory of space shuttle can be accommodated by an aircraft flying parallel to the orbiter reentry ground track. Thermal information from the sides of the vehicle can be obtained with degraded performance (temperatures below 800 K) by flying the C-141 aircraft on the opposite side of the shuttle ground track and in the direction opposite that which is optimum for lower surface viewing. An acquisition system using a 6.25-cm aperture telescope and a single indium antimonide detector were designed to meet the acquisition requirements and interface with the 91.5-cm telescope with minimum modification. An image plane system using 600 indium antimonide detectors in two arrays which requires no modification to the existing telescope was also designed. Currently available components were used in a data handling system with interfaces with the experimentors station and the HP2100 computer.

PCE/TCE DEGRADATION USING MULCH BIOWALLS

EPA Science Inventory

A passive reactive barrier (Biowall) was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contamin...

Pressure dependence of the magnetic ground states in MnP

DOE PAGES

Matsuda, Masaaki; Ye, Feng; Dissanayake, Sachith E.; ...

2016-03-17

MnP, a superconductor under pressure, exhibits a ferromagnetic order below TC~290 K followed by a helical order with the spins lying in the ab plane and the helical rotation propagating along the c axis below Ts~50 K at ambient pressure. We performed single-crystal neutron diffraction experiments to determine the magnetic ground states under pressure. Both TC and Ts are gradually suppressed with increasing pressure and the helical order disappears at ~1.2 GPa. At intermediate pressures of 1.8 and 2.0 GPa, the ferromagnetic order first develops and changes to a conical or two-phase (ferromagnetic and helical) structure with the propagation alongmore » the b axis below a characteristic temperature. At 3.8 GPa, a helical magnetic order appears below 208 K, which hosts the spins in the ac plane and the propagation along the b axis. The period of this b axis modulation is shorter than that at 1.8 GPa. Here, our results indicate that the magnetic phase in the vicinity of the superconducting phase may have a helical magnetic correlation along the b axis.« less

Definition of technology development missions for early space stations orbit transfer vehicle serving. Phase 2, task 1: Space station support of operational OTV servicing

NASA Technical Reports Server (NTRS)

1983-01-01

Representative space based orbital transfer vehicles (OTV), ground based vehicle turnaround assessment, functional operational requirements and facilities, mission turnaround operations, a comparison of ground based versus space based tasks, activation of servicing facilities prior to IOC, fleet operations requirements, maintenance facilities, OTV servicing facilities, space station support requirements, and packaging for delivery are discussed.

Deficient motion-defined and texture-defined figure-ground segregation in amblyopic children.

PubMed

Wang, Jane; Ho, Cindy S; Giaschi, Deborah E

2007-01-01

Motion-defined form deficits in the fellow eye and the amblyopic eye of children with amblyopia implicate possible direction-selective motion processing or static figure-ground segregation deficits. Deficient motion-defined form perception in the fellow eye of amblyopic children may not be fully accounted for by a general motion processing deficit. This study investigates the contribution of figure-ground segregation deficits to the motion-defined form perception deficits in amblyopia. Performances of 6 amblyopic children (5 anisometropic, 1 anisostrabismic) and 32 control children with normal vision were assessed on motion-defined form, texture-defined form, and global motion tasks. Performance on motion-defined and texture-defined form tasks was significantly worse in amblyopic children than in control children. Performance on global motion tasks was not significantly different between the 2 groups. Faulty figure-ground segregation mechanisms are likely responsible for the observed motion-defined form perception deficits in amblyopia.

Ground penetrating radar: a case study for estimating root bulking rate in cassava (Manihot esculenta Crantz).

PubMed

Delgado, Alfredo; Hays, Dirk B; Bruton, Richard K; Ceballos, Hernán; Novo, Alexandre; Boi, Enrico; Selvaraj, Michael Gomez

2017-01-01

Understanding root traits is a necessary research front for selection of favorable genotypes or cultivation practices. Root and tuber crops having most of their economic potential stored below ground are favorable candidates for such studies. The ability to image and quantify subsurface root structure would allow breeders to classify root traits for rapid selection and allow agronomist the ability to derive effective cultivation practices. In spite of the huge role of Cassava ( Manihot esculenta Crantz), for food security and industrial uses, little progress has been made in understanding the onset and rate of the root-bulking process and the factors that influence it. The objective of this research was to determine the capability of ground penetrating radar (GPR) to predict root-bulking rates through the detection of total root biomass during its growth cycle. Our research provides the first application of GPR for detecting below ground biomass in cassava. Through an empirical study, linear regressions were derived to model cassava bulking rates. The linear equations derived suggest that GPR is a suitable measure of root biomass ( r  = .79). The regression analysis developed accounts for 63% of the variability in cassava biomass below ground. When modeling is performed at the variety level, it is evident that the variety models for SM 1219-9 and TMS 60444 outperform the HMC-1 variety model (r 2  = .77, .63 and .51 respectively). Using current modeling methods, it is possible to predict below ground biomass and estimate root bulking rates for selection of early root bulking in cassava. Results of this approach suggested that the general model was over predicting at early growth stages but became more precise in later root development.

Below-ground carbon flux and partitioning: global patterns and response to temperature

Treesearch

C.M. Litton; C.P. Giardina

2008-01-01

1. The fraction of gross primary production (GPP) that is total below-ground carbon flux (TBCF) and the fraction of TBCF that is below-ground net primary production (BNPP) represent globally significant C fluxes that are fundamental in regulating ecosystem C balance. However, global estimates of the partitioning of GPP to TBCF and of TBCF to BNPP, as well as the...

Impacts of an Invasive Non-Native Annual Weed, Impatiens glandulifera, on Above- and Below-Ground Invertebrate Communities in the United Kingdom

PubMed Central

Tanner, Robert A.; Varia, Sonal; Eschen, René; Wood, Suzy; Murphy, Sean T.; Gange, Alan C.

2013-01-01

Vegetation community composition and the above- and below-ground invertebrate communities are linked intrinsically, though few studies have assessed the impact of non-native plants on both these parts of the community together. We evaluated the differences in the above- (foliage- and ground-dwelling) and below-ground invertebrate communities in nine uninvaded plots and nine plots invaded by the annual invasive species Impatiens glandulifera, in the UK during 2007 and 2008. Over 139,000 invertebrates were identified into distinct taxa and categorised into functional feeding groups. The impact of I. glandulifera on the vegetation and invertebrate community composition was evaluated using multivariate statistics including principal response curves (PRC) and redundancy analysis (RDA). In the foliage-dwelling community, all functional feeding groups were less abundant in the invaded plots, and the species richness of Coleoptera and Heteroptera was significantly reduced. In the ground-dwelling community, herbivores, detritivores, and predators were all significantly less abundant in the invaded plots. In contrast, these functional groups in the below-ground community appeared to be largely unaffected, and even positively associated with the presence of I. glandulifera. Although the cover of I. glandulifera decreased in the invaded plots in the second year of the study, only the below-ground invertebrate community showed a significant response. These results indicate that the above- and below-ground invertebrate communities respond differently to the presence of I. glandulifera, and these community shifts can potentially lead to a habitat less biologically diverse than surrounding native communities; which could have negative impacts on higher trophic levels and ecosystem functioning. PMID:23840648

Global Ground Motion Prediction Equations Program | Just another WordPress

Science.gov Websites

Motion Task 2: Compile and Critically Review GMPEs Task 3: Select or Derive a Global Set of GMPEs Task 6 : Design the Specifications to Compile a Global Database of Soil Classification Task 5: Build a Database of Update on PEER's Global GMPEs Project from recent workshop in Turkey Posted on June 11, 2012 During May

Diurnal dynamics of oxygen and carbon dioxide concentrations in shoots and rhizomes of a perennial in a constructed wetland indicate down-regulation of below ground oxygen consumption

PubMed Central

Faußer, Anna C.; Dušek, Jiří; Čížková, Hana; Kazda, Marian

2016-01-01

Wetland plants actively provide oxygen for aerobic processes in submerged tissues and the rhizosphere. The novel concomitant assessment of diurnal dynamics of oxygen and carbon dioxide concentrations under field conditions tests the whole-system interactions in plant-internal gas exchange and regulation. Oxygen concentrations ([O2]) were monitored in-situ in central culm and rhizome pith cavities of common reed (Phragmites australis) using optical oxygen sensors. The corresponding carbon dioxide concentrations ([CO2]) were assessed via gas samples from the culms. Highly dynamic diurnal courses of [O2] were recorded, which started at 6.5–13 % in the morning, increased rapidly up to 22 % during midday and declined exponentially during the night. Internal [CO2] were high in the morning (1.55–17.5 %) and decreased (0.04–0.94 %) during the rapid increase of [O2] in the culms. The observed negative correlations between [O2] and [CO2] particularly describe the below ground relationship between plant-mediated oxygen supply and oxygen use by respiration and biogeochemical processes in the rhizosphere. Furthermore, the nocturnal declining slopes of [O2] in culms and rhizomes indicated a down-regulation of the demand for oxygen in the complete below ground plant-associated system. These findings emphasize the need for measurements of plant-internal gas exchange processes under field conditions because it considers the complex interactions in the oxic-anoxic interface. PMID:27207278

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

RATE OF TCE DEGRADATION IN A PLANT MULCH PASSIVE REACTIVE BARRIER (BIOWALL)

EPA Science Inventory

A passive reactive barrier was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contaminated groun...

THE CONTRIBUTION OF MICROARTHROPODS TO ABOVE GROUND FOOD WEBS: A REVIEW AND MODEL OF BELOW GROUND TRANSFER IN A CONIFEROUS FOREST

EPA Science Inventory

Although belowground food webs have received much attention, studies concerning microarthropods in nondetrital food webs are scarce. Because adult oribatid mites often number between 250,000-500,000/m(2) in coniferous forests, microarthropods are a potential food resource for mic...

The role of the geothermal gradient in the emplacement and replenishment of ground ice on Mars

NASA Technical Reports Server (NTRS)

Clifford, Stephen M.

1993-01-01

Knowledge of the mechanisms by which ground ice is emplaced, removed, and potentially replenished, are critical to understanding the climatic and hydrologic behavior of water on Mars, as well as the morphologic evolution of its surface. Because of the strong temperature dependence of the saturated vapor pressure of H2O, the atmospheric emplacement or replenishment of ground ice is prohibited below the depth at which crustal temperatures begin to monotonically increase due to geothermal heating. In contrast, the emplacement and replenishment of ground ice from reservoirs of H2O residing deep within the crust can occur by at least three different thermally-driven processes, involving all three phases of water. In this regard, Clifford has discussed how the presence of a geothermal gradient as small as 15 K/km can give rise to a corresponding vapor pressure gradient sufficient to drive the vertical transport of 1 km of water from a reservoir of ground water at depth to the base of the cryosphere every 10(exp 6) - 10(exp 7) years. This abstract expands on this earlier treatment by considering the influence of thermal gradients on the transport of H2O at temperatures below the freezing point.

Comparative Analyses of Cuticular Waxes on Various Organs of Potato (Solanum tuberosum L.).

PubMed

Guo, Yanjun; Jetter, Reinhard

2017-05-17

Complex mixtures of cuticular waxes coat plant surfaces to seal them against environmental stresses, with compositions greatly varying between species and possibly organs. This paper reports comprehensive analyses of the waxes on both above- and below-ground organs of potato, where total wax coverages varied between petals (2.6 μg/cm 2 ), leaves, stems, and tubers (1.8-1.9 μg/cm 2 ), and rhizomes (1.1 μg/cm 2 ). The wax mixtures on above-ground organs were dominated by alkanes, occurring in homologous series of isomeric C 25 -C 35 n-alkanes, C 25 -C 35 2-methylalkanes, and C 26 -C 34 3-methylalkanes. In contrast, below-ground organs had waxes rich in monoacylglycerols (C 22 -C 28 acyls) and C 18 -C 30 alkyl ferulates, together with fatty acids (rhizomes) or primary alcohols (tubers). The organ-specific wax coverages, compound class distribution, and chain length profiles suggest highly regulated activities of wax biosynthesis enzymes, likely related to organ-specific ecophysiological functions.

Figure-ground asymmetries in the Implicit Association Test (IAT).

PubMed

Rothermund, K; Wentura, D

2001-01-01

Based on the assumption that binary classification tasks are often processed asymmetrically (figure-ground asymmetries), two experiments showed that association alone cannot account for effects observed in the Implicit Association Test (IAT). Experiment 1 (N = 16) replicated a standard version of the IAT effect using old vs. young names as target categories and good and bad words as attribute categories. However, reliable compatibility effects were also found for a modified version of the task in which neutral words vs. nonwords instead of good vs. bad words were used as attribute categories. In Experiment 2 (N = 8), a reversed IAT effect was observed after the figure-ground asymmetry in the target dimension had been inverted by a previous go/nogo detection task in which participants searched for exemplars of the category "young." The experiments support the hypothesis that figure-ground asymmetries produce compatibility effects in the IAT and suggest that IAT effects do not rely exclusively on evaluative associations between the target and attribute categories.

Changes in Soil Microbial Community Structure with Flooding

USDA-ARS?s Scientific Manuscript database

Flooding disturbs both above- and below-ground ecosystem processes. Although often ignored, changes in below-ground environments are no less important than those that occur above-ground. Shifts in soil microbial community structure are expected when anaerobic conditions develop from flooding. The ...

Ground/Air Task Oriented Radar (G/ATOR)

DTIC Science & Technology

2015-12-01

Selected Acquisition Report ( SAR ) RCS: DD-A&T(Q&A)823-386 Ground/Air Task Oriented Radar (G/ATOR) As of FY 2017 President’s Budget Defense...Acquisition Management Information Retrieval (DAMIR) March 18, 2016 06:47:59 UNCLASSIFIED G/ATOR December 2015 SAR March 18, 2016 06:47:59 UNCLASSIFIED 2...Document OSD - Office of the Secretary of Defense O&S - Operating and Support PAUC - Program Acquisition Unit Cost G/ATOR December 2015 SAR March 18

Hydraulic Universal Display Processor System (HUDPS).

DTIC Science & Technology

1981-11-21

emphasis on smart alphanumeric devices in Task II. Volatile and non-volatile memory components were utilized along with the Intel 8748 microprocessor...system. 1.2 TASK 11 Fault display methods for ground support personnel were investigated during Phase II with emphasis on smart alphanumeric devices...CONSIDERATIONS Methods of display fault indication for ground support personnel have been investigated with emphasis on " smart " alphanumeric devices

Competing magnetic ground states and their coupling to the crystal lattice in CuFe 2Ge 2

DOE PAGES

May, Andrew F.; Calder, Stuart; Parker, David S.; ...

2016-10-14

Identifying and characterizing systems with coupled and competing interactions is central to the development of physical models that can accurately describe and predict emergent behavior in condensed matter systems. This work demonstrates that the metallic compound CuFe 2Ge 2 has competing magnetic ground states, which are shown to be strongly coupled to the lattice and easily manipulated using temperature and applied magnetic fields. The temperature-dependent magnetization M measurements reveal a ferromagnetic-like onset at 228 (1) K and a broad maximum in M near 180 K. Powder neutron diffraction confirms antiferromagnetic ordering below T N ≈ 175 K, and an incommensuratemore » spin density wave is observed below ≈125 K. Coupled with the small refined moments (0.5–1 μB/Fe), this provides a picture of itinerant magnetism in CuFe 2Ge 2. Furthermore, the neutron diffraction data reveal a coexistence of two magnetic phases that further highlights the near-degeneracy of various magnetic states. Our results demonstrate that the ground state in CuFe 2Ge 2 can be easily manipulated by external forces, making it of particular interest for doping, pressure, and further theoretical studies.« less

Revisiting static and dynamic spin-ice correlations in Ho2Ti2O7 with neutron scattering

NASA Astrophysics Data System (ADS)

Clancy, J. P.; Ruff, J. P. C.; Dunsiger, S. R.; Zhao, Y.; Dabkowska, H. A.; Gardner, J. S.; Qiu, Y.; Copley, J. R. D.; Jenkins, T.; Gaulin, B. D.

2009-01-01

Elastic and inelastic neutron-scattering studies have been carried out on the pyrochlore magnet Ho2Ti2O7 . Measurements in zero applied magnetic field show that the disordered spin-ice ground state of Ho2Ti2O7 is characterized by a pattern of rectangular diffuse elastic scattering within the [HHL] plane of reciprocal space, which closely resembles the zone-boundary scattering seen in its sister compound Dy2Ti2O7 . Well-defined peaks in the zone-boundary scattering develop only within the spin-ice ground state below ˜2K . In contrast, the overall diffuse-scattering pattern evolves on a much higher-temperature scale of ˜17K . The diffuse scattering at small wave vectors below [001] is found to vanish on going to Q=0 , an explicit signature of expectations for dipolar spin ice. Very high energy-resolution inelastic measurements reveal that the spin-ice ground state below ˜2K is also characterized by a transition from dynamic to static spin correlations on the time scale of 10-9s . Measurements in a magnetic field applied along the [11¯0] direction in zero-field-cooled conditions show that the system can be broken up into orthogonal sets of polarized α chains along [11¯0] and quasi-one-dimensional β chains along [110]. Three-dimensional correlations between β chains are shown to be very sensitive to the precise alignment of the [11¯0] externally applied magnetic field.

Extent and Depth to Top of Basalt and Interbed Hydrogeologic Units, Yakima River Basin Aquifer System, Washington

USGS Publications Warehouse

Jones, M.A.; Vaccaro, J.J.

2008-01-01

The hydrogeologic framework was delineated for the ground-water flow system of the three basalt formations and two interbeds in the Yakima River Basin, Washington. The basalt units are nearly equivalent to the Saddle Mountains, Wanapum, and Grande Ronde. The two major interbed units between the basalt formations generally are referred to as the Mabton and Vantage. The basalt formations are a productive source of ground-water for the Yakima River Basin. The Grande Ronde unit comprises the largest area in the Yakima River Basin aquifer system. This unit encompasses an area of about 5,390 mi2 and ranges in altitude from 6,900 ft, where it is exposed at land surface, to a depth of 2,800 ft below land surface. The Wanapum unit encompasses an area of 3,450 mi2 and ranges in altitude from 5,680 ft, where exposed at land surface, to a depth of 2,050 ft below land surface. The Saddle Mountains unit, the least extensive, encompasses an area of 2,290 mi2 and ranges from 4,290 ft, where exposed at the surface, to a depth of 1,840 ft below land surface.

Summary of hydrologic data collected during 1976 in Dade County, Florida

USGS Publications Warehouse

Hull, John E.

1978-01-01

During 1976 rainfall was 1.58 inches below the long-term average. Ground-water levels ranged from 0.4 foot above to 0.5 foot below average. The highest and lowest ground water for the year were both 1 foot below their long-term averages. In the Hialeah-Miami Springs area, water levels in wells near the centers of the heaviest pumping ranged from 8.0 to 9.5 feet below msl (mean sea level, 1929); and in the southwest well-field area, ground-water levels near the centers of pumping ranged from 2.0 feet above to 3.0 feet below msl. The combined average daily discharge from nine major streams and canals that flow eastward into tidal waters was 1,666 cubic feet per second (cfs), 609 cfs above the combined average daily flow for the 1975 water year. The combined average daily flow through the Tamiami Canal outlets was 783 cfs, 215 cfs above that of the 1975 water year. The 1976 position of the salt fron in the coastal part of the Biscayne aquifer was about the same as in 1975 except in the vicinity of Mowry Canal south of Homestead Air Force Base where the salt front had encroached farther inland. (Woodard-USGS)

FIELD SCALE EVALUATION OF TREATMENT OF TCE IN A BIOWALL AT THE OU-1 SITE

EPA Science Inventory

A passive reactive barrier (Biowall) was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contamin...

Space sequestration below ground in old-growth spruce-beech forests-signs for facilitation?

PubMed

Bolte, Andreas; Kampf, Friederike; Hilbrig, Lutz

2013-01-01

Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤2 mm) by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1) spruce as a central tree, (2) spruce as competitor, (3) beech as a central tree, and (4) beech as competitor. Mean values of life fine root attributes like biomass (FRB), length (FRL), and root area index (RAI) were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA) exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL) and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA), asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area.

Space sequestration below ground in old-growth spruce-beech forests—signs for facilitation?

PubMed Central

Bolte, Andreas; Kampf, Friederike; Hilbrig, Lutz

2013-01-01

Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤2 mm) by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1) spruce as a central tree, (2) spruce as competitor, (3) beech as a central tree, and (4) beech as competitor. Mean values of life fine root attributes like biomass (FRB), length (FRL), and root area index (RAI) were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA) exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL) and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA), asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area. PMID:24009616

Ground-water temperature of the Wyoming quadrangle in central Delaware : with application to ground-water-source heat pumps

USGS Publications Warehouse

Hodges, Arthur L.

1982-01-01

Ground-water temperature was measured during a one-year period (1980-81) in 20 wells in the Wyoming Quadrangle in central Delaware. Data from thermistors set at fixed depths in two wells were collected twice each week, and vertical temperature profiles of the remaining 18 wells were made monthly. Ground-water temperature at 8 feet below land surface in well Jc55-1 ranged from 45.0 degrees F in February to 70.1 degrees F in September. Temperature at 35 feet below land surface in the same well reached a minimum of 56.0 degrees F in August, and a maximum of 57.8 degrees F in February. Average annual temperature of ground water at 25 feet below land surface in all wells ranged from 54.6 degrees F to 57.8 degrees F. Variations of average temperature probably reflect the presence or absence of forestation in the recharge areas of the wells. Ground-water-source heat pumps supplied with water from wells 30 or more feet below land surface will operate more efficiently in both heating and cooling modes than those supplied with water from shallower depths. (USGS)

A multi-country perspective on nurses' tasks below their skill level: reports from domestically trained nurses and foreign trained nurses from developing countries.

PubMed

Bruyneel, Luk; Li, Baoyue; Aiken, Linda; Lesaffre, Emmanuel; Van den Heede, Koen; Sermeus, Walter

2013-02-01

Several studies have concluded that the use of nurses' time and energy is often not optimized. Given widespread migration of nurses from developing to developed countries, it is important for human resource planning to know whether nursing education in developing countries is associated with more exaggerated patterns of inefficiency. First, to describe nurses' reports on tasks below their skill level. Second, to examine the association between nurses' migratory status (domestically trained nurse or foreign trained nurse from a developing country) and reports on these tasks. The Registered Nurse Forecasting Study used a cross-sectional quantitative research design to gather data from 33,731 nurses (62% response rate) in 486 hospitals in Belgium, England, Finland, Germany, Greece, Ireland, the Netherlands, Norway, Poland, Spain, Sweden and Switzerland. For this analysis, nurse-reported information on migratory status and tasks below their skill level performed during their last shift was used. Random effects models estimated the effect of nurses' migratory status on reports of these tasks. 832 nurses were trained in a developing country (2.5% of total sample). Across countries, a high proportion of both domestically trained and foreign trained nurses from developing countries reported having performed tasks below their skill level during their last shift. After adjusting for nurses' type of last shift worked, years of experience, and level of education, there remained a pronounced overall effect of being a foreign trained nurse from a developing country and an increase in reports of tasks below skill level performed during the last shift. The findings suggest that there remains much room for improvement to optimize the use of nurses' time and energy. Special attention should be given to raising the professional level of practice of foreign trained nurses from developing countries. Further research is needed to understand the influence of professional practice standards, skill levels of foreign trained nurses from developing countries and values attached to these tasks resulting from previous work experiences in their home countries. This will allow us to better understand the conditions under which foreign trained nurses from developing countries can optimally contribute to professional nursing practice in developed country contexts. Copyright © 2012 Elsevier Ltd. All rights reserved.

A new cue to figure-ground coding: top-bottom polarity.

PubMed

Hulleman, Johan; Humphreys, Glyn W

2004-11-01

We present evidence for a new figure-ground cue: top-bottom polarity. In an explicit reporting task, participants were more likely to interpret stimuli with a wide base and a narrow top as a figure. A similar advantage for wide-based stimuli also occurred in a visual short-term memory task, where the stimuli had ambiguous figure-ground relations. Further support comes from a figural search task. Figural search is a discrimination task in which participants are set to search for a symmetric target in a display with ambiguous figure-ground organization. We show that figural search was easier when stimuli with a top-bottom polarity were placed in an orientation where they had a wide base and a narrow top, relative to when this orientation was inverted. This polarity effect was present when participants were set to use color to parse figure from ground, and it was magnified when the participants did not have any foreknowledge of the color of the symmetric target. Taken together the results suggest that top-bottom polarity influences figure-ground assignment, with wide base stimuli being preferred as a figure. In addition, the figural search task can serve as a useful procedure to examine figure-ground assignment.

Informational primacy of visual dimensions: specialized roles for luminance and chromaticity in figure-ground perception.

PubMed

Yamagishi, N; Melara, R D

2001-07-01

Three experiments were conducted to examine the distinct contributions of two visual dimensions to figure-ground segregation. In each experiment, pattern identification was assessed by asking observers to judge whether a near-threshold test pattern was the same or different in shape to a high-contrast comparison pattern. A test pattern could differ from its background along one dimension, either luminance (luminance tasks) or chromaticity (chromaticity tasks). In each task, performance in a baseline condition, in which the test pattern was intact, was compared with performance in each of several degradation conditions, in which either the contour or the surface of the figure was degraded, using either partial occlusion (Experiment 1) or ramping (Experiments 2 and 3) of figure-ground differences. In each experiment, performance in luminance tasks was worst when the contour was degraded, whereas performance in chromaticity tasks was worst when the surface was degraded. This interaction was found even when spatial frequencies were fixed across test patterns by low-pass filtering. The results are consistent with a late (postfiltering) dual-mechanism system that processes luminance information to extract boundary representations and chromaticity information to extract surface representations.

Results of testing landspreading of treated municipal wastewater at St. Petersburg, Florida

USGS Publications Warehouse

Reichenbaugh, R.C.; Brown, David P.; Goetz, Carole L.

1979-01-01

Chlorinated secondary-treated effluent was used to irrigate a grassed 4-acre site at rates of 2 and 4 inches per week for periods of 11 and 14 weeks, respectively. Part of the site was drained by tile lines 5 feet below land surface. Irrigation of the drained plot resulted in rapid passage of the applied wastewater through the soil and, consequently, poor nitrogen removal. The rapid percolation permitted nitrification but prevented denitrification. Total phosphorus in the shallow ground water at the site increased from a maximum of 1.4 milligrams per liter before irrigation to as much as 5 milligrams per liter in the ground water 5 feet below land surface. Concentrations of nitrogen and phosphorus did not increase in ground water downgradient from the site, although increased chloride concentrations demonstrated downgradient migration of the applied wastewater. Prior to irrigation, total coliform bacteria were not detected in ground water at the site. After irrigation, total and fecal coliforms were detected in the ground water at the site and downgradient. (Woodard-USGS)

A 2.5D Map-Based Mobile Robot Localization via Cooperation of Aerial and Ground Robots

PubMed Central

Nam, Tae Hyeon; Shim, Jae Hong; Cho, Young Im

2017-01-01

Recently, there has been increasing interest in studying the task coordination of aerial and ground robots. When a robot begins navigation in an unknown area, it has no information about the surrounding environment. Accordingly, for robots to perform tasks based on location information, they need a simultaneous localization and mapping (SLAM) process that uses sensor information to draw a map of the environment, while simultaneously estimating the current location of the robot on the map. This paper aims to present a localization method based in cooperation between aerial and ground robots in an indoor environment. The proposed method allows a ground robot to reach accurate destination by using a 2.5D elevation map built by a low-cost RGB-D (Red Green and Blue-Depth) sensor and 2D Laser sensor attached onto an aerial robot. A 2.5D elevation map is formed by projecting height information of an obstacle using depth information obtained by the RGB-D sensor onto a grid map, which is generated by using the 2D Laser sensor and scan matching. Experimental results demonstrate the effectiveness of the proposed method for its accuracy in location recognition and computing speed. PMID:29186843

A 2.5D Map-Based Mobile Robot Localization via Cooperation of Aerial and Ground Robots.

PubMed

Nam, Tae Hyeon; Shim, Jae Hong; Cho, Young Im

2017-11-25

Recently, there has been increasing interest in studying the task coordination of aerial and ground robots. When a robot begins navigation in an unknown area, it has no information about the surrounding environment. Accordingly, for robots to perform tasks based on location information, they need a simultaneous localization and mapping (SLAM) process that uses sensor information to draw a map of the environment, while simultaneously estimating the current location of the robot on the map. This paper aims to present a localization method based in cooperation between aerial and ground robots in an indoor environment. The proposed method allows a ground robot to reach accurate destination by using a 2.5D elevation map built by a low-cost RGB-D (Red Green and Blue-Depth) sensor and 2D Laser sensor attached onto an aerial robot. A 2.5D elevation map is formed by projecting height information of an obstacle using depth information obtained by the RGB-D sensor onto a grid map, which is generated by using the 2D Laser sensor and scan matching. Experimental results demonstrate the effectiveness of the proposed method for its accuracy in location recognition and computing speed.

Similarities Between Deaf or Hard of Hearing and Hearing Students' Awareness of Affective Words' Valence in Written Language.

PubMed

Li, Degao; Zhang, Fan; Zeng, Xihong

2016-01-01

An affective priming task was used with two cohorts of college students, one deaf or hard of hearing (D/HH), the other hearing, in two experiments. The same set of affective-word targets, preceded by "※※" in Experiment 1 but by affective-word primes of the same valence as the targets in Experiment 2, were presented vertically above or below the screen center. Stimuli that preceded the targets were shown at the screen center. D/HH participants generally performed more poorly than hearing participants, but both groups performed similarly in that both did better on the positive targets than on the negative in both experiments, and on supporting metaphorical associations between valence and vertical positions (Meier & Robinson, 2004), as indicated by reaction times, in Experiment 2. The researchers concluded that D/HH and hearing college students perform similarly in developing cognition-grounded representations of affective words in written language.

Soil biology research across latitude, elevation and disturbance gradients: A review of forest studies from Puerto Rico during the past 25 years

Treesearch

Grizelle González; D. Lodge

2017-01-01

Progress in understanding changes in soil biology in response to latitude, elevation and disturbance gradients has generally lagged behind studies of above-ground plants and animals owing to methodological constraints and high diversity and complexity of interactions in below-ground food webs. New methods have opened research opportunities in below-ground systems,...

Contribution of above- and below-ground plant traits to the structure and function of grassland soil microbial communities

PubMed Central

Legay, N.; Baxendale, C.; Grigulis, K.; Krainer, U.; Kastl, E.; Schloter, M.; Bardgett, R. D.; Arnoldi, C.; Bahn, M.; Dumont, M.; Poly, F.; Pommier, T.; Clément, J. C.; Lavorel, S.

2014-01-01

Background and Aims Abiotic properties of soil are known to be major drivers of the microbial community within it. Our understanding of how soil microbial properties are related to the functional structure and diversity of plant communities, however, is limited and largely restricted to above-ground plant traits, with the role of below-ground traits being poorly understood. This study investigated the relative contributions of soil abiotic properties and plant traits, both above-ground and below-ground, to variations in microbial processes involved in grassland nitrogen turnover. Methods In mountain grasslands distributed across three European sites, a correlative approach was used to examine the role of a large range of plant functional traits and soil abiotic factors on microbial variables, including gene abundance of nitrifiers and denitrifiers and their potential activities. Key Results Direct effects of soil abiotic parameters were found to have the most significant influence on the microbial groups investigated. Indirect pathways via plant functional traits contributed substantially to explaining the relative abundance of fungi and bacteria and gene abundances of the investigated microbial communities, while they explained little of the variance in microbial activities. Gene abundances of nitrifiers and denitrifiers were most strongly related to below-ground plant traits, suggesting that they were the most relevant traits for explaining variation in community structure and abundances of soil microbes involved in nitrification and denitrification. Conclusions The results suggest that consideration of plant traits, and especially below-ground traits, increases our ability to describe variation in the abundances and the functional characteristics of microbial communities in grassland soils. PMID:25122656

40 CFR 147.3108 - Plugging Class I, II, and III wells.

Code of Federal Regulations, 2014 CFR

2014-07-01

... with a cement plug from there to at least one hundred (100) feet above the top of the disposal or injection zone. (2) A cement plug shall also be set from a point at least fifty (50) feet below the shoe of... cement plug shall extend from a point at least thirty feet below the ground surface to a point five (5...

40 CFR 147.3108 - Plugging Class I, II, and III wells.

Code of Federal Regulations, 2013 CFR

2013-07-01

... with a cement plug from there to at least one hundred (100) feet above the top of the disposal or injection zone. (2) A cement plug shall also be set from a point at least fifty (50) feet below the shoe of... cement plug shall extend from a point at least thirty feet below the ground surface to a point five (5...

40 CFR 147.3108 - Plugging Class I, II, and III wells.

Code of Federal Regulations, 2012 CFR

2012-07-01

... with a cement plug from there to at least one hundred (100) feet above the top of the disposal or injection zone. (2) A cement plug shall also be set from a point at least fifty (50) feet below the shoe of... cement plug shall extend from a point at least thirty feet below the ground surface to a point five (5...

40 CFR 147.3108 - Plugging Class I, II, and III wells.

Code of Federal Regulations, 2011 CFR

2011-07-01

... with a cement plug from there to at least one hundred (100) feet above the top of the disposal or injection zone. (2) A cement plug shall also be set from a point at least fifty (50) feet below the shoe of... cement plug shall extend from a point at least thirty feet below the ground surface to a point five (5...

40 CFR 147.3108 - Plugging Class I, II, and III wells.

Code of Federal Regulations, 2010 CFR

2010-07-01

... with a cement plug from there to at least one hundred (100) feet above the top of the disposal or injection zone. (2) A cement plug shall also be set from a point at least fifty (50) feet below the shoe of... cement plug shall extend from a point at least thirty feet below the ground surface to a point five (5...

Propagation of beam-driven VLF waves from the ionosphere toward the ground

NASA Technical Reports Server (NTRS)

Schriver, David; Sotnikov, Vladimir I.; Ashour-Abdalla, Maha; Ernstmeyer, James

1995-01-01

As part of the Cooperative High Altitude Rocket Gun Experiment (CHARGE-2B) rocket mission, an electron beam was injected into the ionosphere with a modulated beam current in an effort to generate very low frequency (VLF) waves. The propagation of the beam-driven VLF waves through the ionosphere is examined here to determine whether it is possible to detect these wave emissions with ground receivers. The paths of the VLF waves from where they were generated near the rocket were followed to the bottom of the ionosphere and the decrease in wave amplitude due to wave-particle resonance and collisional damping was calculated. It was found that due to collisional damping, which for these VLF waves becomes large at altitudes below about 150 km, wave amplitudes were decreased below the background atmospheric noise level. A number of different beam injection events have been examined and in all of these cases studied the waves were sufficiently damped such that detection on the ground would not be possible. This is in agreement with observations on the ground in which no wave emissions were observed during the CHARGE-2B mission. Control parameters that would be more favorable for beam-generated VLF propagation to the ground are discussed for future experiments of this type.

Seasonal below-ground metabolism in switchgrass

USDA-ARS?s Scientific Manuscript database

Switchgrass (Panicum virgatum) a perennial, polyploid, C4 warm-season grass is one of the foremost herbaceous species being advanced as a source of biomass for biofuel end uses. At the end of every growing season, the aerial tissues senesce, and the below-ground rhizomes become dormant. Future growt...

The inconvenient truth about eddy covariance flux partitioning and implications for global carbon cycle estimates

NASA Astrophysics Data System (ADS)

Wohlfahrt, Georg; Galvagno, Marta

2016-04-01

Ecosystem respiration (ER) and gross primary productivity (GPP) are key carbon cycle concepts. Global estimates of ER and GPP are largely based on measurements of the net ecosystem CO2 exchange by means of the eddy covariance method from which ER and GPP are inferred using so-called flux partitioning algorithms. Using a simple two-source model of ecosystem respiration, consisting of an above-ground respiration source driven by simulated air temperature and a below-ground respiration source driven by simulated soil temperature, we demonstrate that the two most popular flux partitioning algorithms are unable to provide unbiased estimates of daytime ER (ignoring any reduction of leaf mitochondrial respiration) and thus GPP. The bias is demonstrated to be either positive or negative and to depend in a complex fashion on the driving temperature, the ratio of above- to below-ground respiration, the respective temperature sensitivities, the soil depth where the below-ground respiration source originates from (and thus phase and amplitude of soil vs. surface temperature) and day length. The insights from the modeling analysis are subject to a reality check using direct measurements of ER at a grassland where measurements of ER were conducted both during night and day using automated opaque chambers. Consistent with the modeling analysis we find that using air temperature to extrapolate from nighttime to daytime conditions overestimates daytime ER (by 20% or ca. 65 gC m-2 over a 100 day study period), while soil temperature results in an underestimation (by 4% or 12 gC m-2). We conclude with practical recommendations for eddy covariance flux partitioning in the context of the FLUXNET project.

Theoretical and Experimental Studies in Reactive Scattering.

DTIC Science & Technology

1986-08-11

dynamics 3. Three-dimensional reaction dynamics 4. Anisotropic potentials for He + C02, OCS, CS2 .. 5. Production of a high intensity-high energy beam of...involving beams of He atoms, H atoms and metastable H molecules aimed at the determination of potential energy surfaces involving these systems. 2... energy of 0.3 ’, Kcal/mole below the top of the barrier, the reaction probability from ground S"t vibrational state reagent to ground vibrational

A belowground perspective on the drought sensitivity of forests: Towards improved understanding and simulation

DOE PAGES

Phillips, Richard P.; Ibanez, Ines; D’Orangeville, Loic; ...

2016-09-13

Predicted increases in the frequency and intensity of droughts across the temperate biome have highlighted the need to examine the extent to which forests may differ in their sensitivity to water stress. At present, a rich body of literature exists on how leaf- and stem-level physiology influence tree drought responses; however, less is known regarding the dynamic interactions that occur below ground between roots and soil physical and biological factors. Hence, there is a need to better understand how and why processes occurring below ground influence forest sensitivity to drought. Here, we review what is known about tree species’ belowmore » ground strategies for dealing with drought, and how physical and biological characteristics of soils interact with rooting strategies to influence forest sensitivity to drought. Then, we highlight how a below ground perspective of drought can be used in models to reduce uncertainty in predicting the ecosystem consequences of droughts in forests. Lastly, we describe the challenges and opportunities associated with managing forests under conditions of increasing drought frequency and intensity, and explain how a below ground perspective on drought may facilitate improved forest management.« less

A belowground perspective on the drought sensitivity of forests: Towards improved understanding and simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phillips, Richard P.; Ibanez, Ines; D’Orangeville, Loic

Predicted increases in the frequency and intensity of droughts across the temperate biome have highlighted the need to examine the extent to which forests may differ in their sensitivity to water stress. At present, a rich body of literature exists on how leaf- and stem-level physiology influence tree drought responses; however, less is known regarding the dynamic interactions that occur below ground between roots and soil physical and biological factors. Hence, there is a need to better understand how and why processes occurring below ground influence forest sensitivity to drought. Here, we review what is known about tree species’ belowmore » ground strategies for dealing with drought, and how physical and biological characteristics of soils interact with rooting strategies to influence forest sensitivity to drought. Then, we highlight how a below ground perspective of drought can be used in models to reduce uncertainty in predicting the ecosystem consequences of droughts in forests. Lastly, we describe the challenges and opportunities associated with managing forests under conditions of increasing drought frequency and intensity, and explain how a below ground perspective on drought may facilitate improved forest management.« less

An Investigation into the Nature of Non-Voiding Contractions Resulting from Detrusor Hyperreflexia in Neurogenic Bladders Following Spinal Cord Injury

DTIC Science & Technology

2015-06-01

occasioned by numerous, rhythmic high pressure non-voiding contractions (NVC) during normal bladder filling. These NVC are responsible for incontinence...month experiment period) 2c. Final data analysis (data analysis will be ongoing throughout, this will represent the finalization of data period, 0.25...Sub-Tasks 2a and 2b. As of 9/2/14, we have completed much of the data analysis (Sub-Task 2c; see below for results). Analysis of abdominal

Measurement of Productive Capacity: A Methodology for Air Force Enlisted Specialties

DTIC Science & Technology

1992-06-01

measurement across a wide variety of duties (11 for Aircrew Life Support (122X0), 8 for Personnel (732X0), 26 for Aerospace Ground Equipment ( 454X1 ), and 16...50 Tasks 454X1 - 55 Tasks 455X2 - 41 Tasks 732X0 - 38 Tasks The tasks in three of the four AFSs tended to represent certain duty areas more than...others, probably because these duty areas contained the functions most frequently performed by first-term airmen. For AFS 454X1 the tasks represented

Tuning the ground state of the Kondo lattice in UT Bi2 (T = Ag, Au) single crystals

NASA Astrophysics Data System (ADS)

Rosa, Priscila; Luo, Yongkang; Pagliuso, Pascoal; Bauer, Eric; Thompson, Joe; Fisk, Zachary

2015-03-01

Motivated by the interesting magnetic anisotropy found in the Ce-based heavy fermion family Ce TX2 (T = transition metal, X = pnictogen), here we study the novel U-based parent compounds U TBi2 (T = Ag, Au) by combining magnetization, electrical resistivity, and heat-capacity measurements. The single crystals, synthesized by the self-flux method, also crystallize in the tetragonal HfCuSi2-type structure (space group P4/nmm). Interestingly, although UAgBi2 is a low- γ antiferromagnet below TN = 181 K, UAuBi2 is a moderately heavy uniaxial ferromagnet below Tc = 22 K. Nevertheless, both compounds display the easy-magnetization direction along the c-axis and a large magnetocrystalline anisotropy. Our results point out to an incoherent Kondo behaviour in the paramagnetic state and an intricate competition between crystal field effects and two anisotropic exchange interactions, which lead to the remarkable difference in the observed ground states.

Thermal inertia mapping of below ground objects and voids

NASA Astrophysics Data System (ADS)

Del Grande, Nancy K.; Ascough, Brian M.; Rumpf, Richard L.

2013-05-01

Thermal inertia (effusivity) contrast marks the borders of naturally heated below ground object and void sites. The Dual Infrared Effusivity Computed Tomography (DIRECT) method, patent pending, detects and locates the presence of enhanced heat flows from below ground object and void sites at a given area. DIRECT maps view contrasting surface temperature differences between sites with normal soil and sites with soil disturbed by subsurface, hollow or semi-empty object voids (or air gaps) at varying depths. DIRECT utilizes an empirical database created to optimize the scheduling of daily airborne thermal surveys to view and characterize unseen object and void types, depths and volumes in "blind" areas.

Completing below-ground carbon budgets for pastures, recovering forests, and mature forests of Amazonia

NASA Technical Reports Server (NTRS)

Davidson, Eric A.; Nepstad, Daniel C.; Trumbore, Susan E.

1994-01-01

The objective of this grant was to complete below-ground carbon budgets for pastures and forest soils in the Amazon. Profiles of radon and carbon dioxide were used to estimate depth distribution of CO2 production in soil. This information is necessary for determining the importance of deep roots as sources of carbon inputs. Samples were collected for measuring root biomass from new research sites at Santana de Araguaia and Trombetas. Soil gases will be analyzed for CO2 and (14)CO2, and soil organic matter will be analyzed for C-14. Estimates of soil texture from the RADAMBRASIL database were merged with climate data to calculate soil water extraction by forest canopies during the dry season. In addition, a preliminary map of areas where deep roots are needed for deep soil water was produced. A list of manuscripts and papers prepared during the reporting periods is given.

Ground-Water Temperature Data, Nevada Test Site and Vicinity, Nye, Clark, and Lincoln Counties, Nevada, 2000-2006

USGS Publications Warehouse

Reiner, Steven R.

2007-01-01

Ground-water temperature data were collected by the U.S. Geological Survey in wells at and in the vicinity of the Nevada Test Site during the years 2000-2006. Periodic ground-water temperatures were collected in 166 wells. In general, periodic ground-water temperatures were measured annually in each well at 5 and 55 feet below the water surface. Ground-water temperature profiles were collected in 73 wells. Temperatures were measured at multiple depths below the water surface to produce these profiles. Databases were constructed to present the ground-water temperature data.

Ground-Water Temperature Data, Nevada Test Site and Vicinity, Nye, Clark, and Lincoln Counties, Nevada, 2000-2006.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steven R. Reiner

2007-08-07

Ground-water temperature data were collected by the U.S. Geological Survey in wells at and in the vicinity of the Nevada Test Site during the years 2000–2006. Periodic ground-water temperatures were collected in 166 wells. In general, periodic ground-water temperatures were measured annually in each well at 5 and 55 feet below the water surface. Ground-water temperature profiles were collected in 73 wells. Temperatures were measured at multiple depths below the water surface to produce these profiles. Databases were constructed to present the ground-water temperature data.

Environmental surfaces and the compression of perceived visual space

PubMed Central

Bian, Zheng; Andersen, George J.

2011-01-01

The present study examined whether the compression of perceived visual space varies according to the type of environmental surface being viewed. To examine this issue, observers made exocentric distance judgments when viewing simulated 3D scenes. In 4 experiments, observers viewed ground and ceiling surfaces and performed either an L-shaped matching task (Experiments 1, 3, and 4) or a bisection task (Experiment 2). Overall, we found considerable compression of perceived exocentric distance on both ground and ceiling surfaces. However, the perceived exocentric distance was less compressed on a ground surface than on a ceiling surface. In addition, this ground surface advantage did not vary systematically as a function of the distance in the scene. These results suggest that the perceived visual space when viewing a ground surface is less compressed than the perceived visual space when viewing a ceiling surface and that the perceived layout of a surface varies as a function of the type of the surface. PMID:21669858

Measuring the EMS patient access time interval and the impact of responding to high-rise buildings.

PubMed

Morrison, Laurie J; Angelini, Mark P; Vermeulen, Marian J; Schwartz, Brian

2005-01-01

To measure the patient access time interval and characterize its contribution to the total emergency medical services (EMS) response time interval; to compare the patient access time intervals for patients located three or more floors above ground with those less than three floors above or below ground, and specifically in the apartment subgroup; and to identify barriers that significantly impede EMS access to patients in high-rise apartments. An observational study of all patients treated by an emergency medical technician paramedics (EMT-P) crew was conducted using a trained independent observer to collect time intervals and identify potential barriers to access. Of 118 observed calls, 25 (21%) originated from patients three or more floors above ground. The overall median and 90th percentile (95% confidence interval) patient access time intervals were 1.61 (1.27, 1.91) and 3.47 (3.08, 4.05) minutes, respectively. The median interval was 2.73 (2.22, 3.03) minutes among calls from patients located three or more stories above ground compared with 1.25 (1.07, 1.55) minutes among those at lower levels. The patient access time interval represented 23.5% of the total EMS response time interval among calls originating less than three floors above or below ground and 32.2% of those located three or more stories above ground. The most frequently encountered barriers to access included security code entry requirements, lack of directional signs, and inability to fit the stretcher into the elevator. The patient access time interval is significantly long and represents a substantial component of the total EMS response time interval, especially among ambulance calls originating three or more floors above ground. A number of barriers appear to contribute to delayed paramedic access.

Comparison Virtual Landing Gear Drop Test for Commuter Aircraft Utilize MSC ADAMS And Solidworks Motion Analysis

NASA Astrophysics Data System (ADS)

Hidayat, Dony; Istiyanto, Jos; Agus Sumarsono, Danardono

2018-04-01

Loads at main landing gear while touchdown impact is function of aircraft weight and ground reaction load factor. In regulation states ground reaction load factor at Vsink = 3.05 m/s is below 3. Contact/impact force from simulation using MSC ADAMS is 94680 N, while using Solidworks Motion Analysis is 97691 N. The difference between MSC ADAMS and Solidworks Motion Analysis is 3.08%. The ground reaction load factor in MSC ADAMS is 2.78 while in Solidworks Motion Analysis is 2.87.

How much older are Appalachian oaks below-ground than above-ground?

Treesearch

Daniel J. Heggenstaller; Eric K. Zenner; Patrick H. Brose; Jerilynn E. Peck

2012-01-01

Young oaks (Quercus spp.) are known to invest more in early root growth than shoot growth, enabling seedlings to tolerate stem die-back and resprouting. The resulting disparity in age between above- and below-ground tissues has been previously demonstrated for seedling-sized stems, but not for successful canopy-ascending trees. We compared the age of stem cross...

Neural evidence for competition-mediated suppression in the perception of a single object.

PubMed

Cacciamani, Laura; Scalf, Paige E; Peterson, Mary A

2015-11-01

Multiple objects compete for representation in visual cortex. Competition may also underlie the perception of a single object. Computational models implement object perception as competition between units on opposite sides of a border. The border is assigned to the winning side, which is perceived as an object (or "figure"), whereas the other side is perceived as a shapeless ground. Behavioral experiments suggest that the ground is inhibited to a degree that depends on the extent to which it competed for object status, and that this inhibition is relayed to low-level brain areas. Here, we used fMRI to assess activation for ground regions of task-irrelevant novel silhouettes presented in the left or right visual field (LVF or RVF) while participants performed a difficult task at fixation. Silhouettes were designed so that the insides would win the competition for object status. The outsides (grounds) suggested portions of familiar objects in half of the silhouettes and novel objects in the other half. Because matches to object memories affect the competition, these two types of silhouettes operationalized, respectively, high competition and low competition from the grounds. The results showed that activation corresponding to ground regions was reduced for high- versus low-competition silhouettes in V4, where receptive fields (RFs) are large enough to encompass the familiar objects in the grounds, and in V1/V2, where RFs are much smaller. These results support a theory of object perception involving competition-mediated ground suppression and feedback from higher to lower levels. This pattern of results was observed in the left hemisphere (RVF), but not in the right hemisphere (LVF). One explanation of the lateralized findings is that task-irrelevant silhouettes in the RVF captured attention, allowing us to observe these effects, whereas those in the LVF did not. Experiment 2 provided preliminary behavioral evidence consistent with this possibility. Copyright © 2015 Elsevier Ltd. All rights reserved.

Summary of hydrologic data collected during 1977 in Dade County, Florida

USGS Publications Warehouse

Hull, John E.

1979-01-01

During 1977 rainfall was 1.52 inches above the long-term average in Dade County, Fla. Ground-water levels ranged from 0.3 foot above to 0.1 foot below average. The highest and lowest ground-water levels for the year were 1 foot below and 1 foot above their long-term average. In the Hialeah-Miami Springs area , water levels in wells near the centers of the heaviest pumping ranged from 7.2 to 11.9 feet below mean sea level, 1929; and in the Southwest well-field area, ground-water levels near the centers of pumping ranged from 1.0 foot above to 1.5 feet below mean sea level. In 1977 the combined average daily discharge from nine major streams and canals that flow eastward into tidal waters was 1,712 cubic feet per second (cfs), 46 cfs above the combined average daily flow for 1976. The combined average daily flow through the Tamiami Canal outlets was 582 cfs, 201 cfs above that of 1976. The 1977 position of the salt front in the coastal part of the Biscayne aquifer was about the same as in 1976, except south of Homestead Air Force Base where the salt front had encroached farther inland. (Woodard-USGS)

Ground-Water Quality Data in the Kern County Subbasin Study Unit, 2006 - Results from the California GAMA Program

USGS Publications Warehouse

Shelton, Jennifer L.; Pimentel, Isabel; Fram, Miranda S.; Belitz, Kenneth

2008-01-01

Ground-water quality in the approximately 3,000 square-mile Kern County Subbasin study unit (KERN) was investigated from January to March, 2006, as part of the Priority Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The Kern County Subbasin study was designed to provide a spatially unbiased assessment of raw (untreated) ground-water quality within KERN, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 50 wells within the San Joaquin Valley portion of Kern County. Forty-seven of the wells were selected using a randomized grid-based method to provide a statistical representation of the ground-water resources within the study unit. Three additional wells were sampled to aid in the evaluation of changes in water chemistry along regional ground-water flow paths. The ground-water samples were analyzed for a large number of man-made organic constituents (volatile organic compounds [VOCs], pesticides, and pesticide degradates), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14, and stable isotopes of hydrogen, oxygen, nitrogen, and carbon) and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, and laboratory matrix spikes) were collected and analyzed at approximately 10 percent of the wells, and the results for these samples were used to evaluate the quality of the data from the ground-water samples. Assessment of the quality-control information resulted in censoring of less than 0.4 percent of the data collected for ground-water samples. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw ground water typically is treated, disinfected, or blended with other waters to maintain acceptable water quality. Regulatory thresholds apply, not to the raw ground water, but to treated water that is served to the consumer. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH), and as well as with thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. VOCs and pesticides each were detected in approximately 60 percent of the grid wells, and detections of all compounds but one were below health-based thresholds. The fumigant, 1,2-dibromo-3-chloropropane (DBCP), was detected above the USEPA maximum contaminant level (MCL-US) in one sample. Detections of most inorganic constituents were also below health-based thresholds. Constituents detected above health-based thresholds include: nitrate, (MCL-US, 2 samples), arsenic (MCL-US, 2 samples), and vanadium (California notification level, NL-CA, 1 sample). All detections of radioactive constituents were below health-based thresholds, although nine samples had activities of radon-222 above the lower proposed MCL-US. Most of the samples from KERN wells had concentrations of major elements, total dissolved solids, and trace elements below the non-enforceable thresholds set for aesthetic concerns.

Ground Truth Creation for Complex Clinical NLP Tasks - an Iterative Vetting Approach and Lessons Learned.

PubMed

Liang, Jennifer J; Tsou, Ching-Huei; Devarakonda, Murthy V

2017-01-01

Natural language processing (NLP) holds the promise of effectively analyzing patient record data to reduce cognitive load on physicians and clinicians in patient care, clinical research, and hospital operations management. A critical need in developing such methods is the "ground truth" dataset needed for training and testing the algorithms. Beyond localizable, relatively simple tasks, ground truth creation is a significant challenge because medical experts, just as physicians in patient care, have to assimilate vast amounts of data in EHR systems. To mitigate potential inaccuracies of the cognitive challenges, we present an iterative vetting approach for creating the ground truth for complex NLP tasks. In this paper, we present the methodology, and report on its use for an automated problem list generation task, its effect on the ground truth quality and system accuracy, and lessons learned from the effort.

Applicability of Performance Assessment Tools to Marine Corps Air Ground Task Force C4 System of Systems Performance Assessment

DTIC Science & Technology

2010-09-01

application of existing assessment tools that may be applicable to Marine Air Ground Task Force (MAGTF) Command, Control, Communications and...of existing assessment tools that may be applicable to Marine Air Ground Task Force (MAGTF) Command, Control, Communications and Computers (C4...assessment tools and analysis concepts that may be extended to the Marine Corps’ C4 System of Systems assessment methodology as a means to obtain a

Does the seed bank contribute to the build-up of a genetic extinction debt in the grassland perennial Campanula rotundifolia?

PubMed

Plue, Jan; Vandepitte, Katrien; Honnay, Olivier; Cousins, Sara A O

2017-09-01

Habitat fragmentation threatens global biodiversity. Many plant species persist in habitat fragments via persistent life cycle stages such as seed banks, generating a species extinction debt. Here, seed banks are hypothesized to cause a temporal delay in the expected loss of genetic variation, which can be referred to as a genetic extinction debt, as a possible mechanism behind species extinction debts. Fragmented grassland populations of Campanula rotundifolia were examined for evidence of a genetic extinction debt, investigating if the seed bank contributed to the extinction debt build-up. The genetic make-up of 15 above- and below-ground populations was analysed in relation to historical and current levels of habitat fragmentation, both separately and combined. Genetic diversity was highest in above-ground populations, though below-ground populations contained 8 % of unique alleles that were absent above-ground. Above-ground genetic diversity and composition were related to historical patch size and connectivity, but not current patch characteristics, suggesting the presence of a genetic extinction debt in the above-ground populations. No such relationships were found for the below-ground populations. Genetic diversity measures still showed a response to historical but not present landscape characteristics when combining genetic diversity of the above- and below-ground populations. The fragmented C. rotundifolia populations exhibited a genetic extinction debt. However, the role of the seed banks in the build-up of this extinction debt is probably small, since the limited, unique genetic diversity of the seed bank alone seems unable to counter the detrimental effects of habitat fragmentation on the population genetic structure of C. rotundifolia. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Performance of Planted Herbaceous Species in Longleaf Pine (Pinus palustris Mill.) Plantations: Overstory Effects of Competition and Needlefall

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dagley, C.M.

2001-07-03

Research to determine the separate effects of above-ground and below-ground competition and needlefall of over-story pines on under-story plant performance. Periodic monitoring of over-story crown closure, soil water content, temperature, and nutrients were conducted. Results indicate competition for light had a more determental effect on performance of herbaceous species in longleaf pine plantations than that resulting from competition for below-ground resources.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Law, A.G.; Serkowski, J.A.; Schatz, A.L.

The Separations Area ground-water monitoring network consisted of 137 wells. Samples from wells in the monitoring network were collected on a monthly, quarterly, or semiannual schedule, depending on the history of the liquid waste disposal site. Samples were analyzed selectively for total alpha, total beta, tritium, /sup 90/Sr, /sup 137/Cs, /sup 60/Co, /sup 106/Ru, total uranium and nitrate. Average concentrations of contaminants in most wells were essentially the same in 1986 as in 1985. The DCG for tritium was exceeded at two PUREX cribs. The ACL specified for /sup 90/Sr was exceeded in three wells near the 216-A-25 Pond. Disposalmore » of effluents to the pond decreased as the main pond was reduced in width to a ditch leading the overflow pond. The ACL guidelines for uranium were exceeded although concentrations were below the DCG; the source of this uranium is probably the inactive 216-B-12 crib. Uranium concentrations above the ACL but below the DCG were also observed at the 216-U-14 ditch and the source is under evaluation. The inactive 216-B-5 reverse well exceeded the DCG for /sup 90/Sr and the ACL for /sup 137/Cs and uranium. Inactive facilities exceeding Rockwell guidelines were the 216-S-1/2 cribs, 216-U-1/2 cribs, the 216-U-10 pond, and the 216-U-6 crib. The 216-S-1/2 cribs have historically had high /sup 137/Cs concentrations because of localized contamination but are below the DCG. Uranium concentrations, which are above the DCG, have stabilized at the 216-U-1/2 cribs after the remedial pumping and uranium removal conducted in 1985. Possible additional action is currently being evaluated. Disposal of the effluent from the ion exchange column to the 216-S-25 crib resulted in ground-water concentrations that exceeded Rockwell guidelines but below the DCG. Ground water near the 216-U-10 pond remains elevated but below the DCG due to past disposal to the pond, which was deactivated in 1984. 23 refs., 25 figs., 26 tabs.« less

Temperature Profile of a Stoichiometric CH4/N2O Flame from Laser Excited Fluorescence Measurements on OH,

DTIC Science & Technology

1982-07-01

19 6. Burner Body Temperature at Several Points Below the Edge of the Burner Head............................ 20 7. An Example of Data Used...effects almost certainly influenced the results of Wang and Davis1 who attributed a plot with two straight-line portions to nonequilibrium distributions of...ground state is equilibrated, one has N, Ja (2J"+l)exp(- EN ,, j,,/kT) (2) where EN ,J1 is the ground state energy, k is Boltzmann’s constant and T is the

Above- and below-ground characteristics associated with wind toppling in a young Populus plantation.

Treesearch

Constance A. Harrington; Dean S. DeBell

1996-01-01

Damage from a dormant-season windstorm in a 3-year-old Populus research trial differed among four clones and three spacings and between monoclonal and polyclonal plots. Clonal differences in susceptibility to toppling (or leaning) were associated with both above and below-ground characteristics. Susceptible clones had less taper in the lower stem...

Comparison of flying qualities derived from in-flight and ground-based simulators for a jet-transport airplane for the approach and landing pilot tasks

NASA Technical Reports Server (NTRS)

Grantham, William D.

1989-01-01

The primary objective was to provide information to the flight controls/flying qualities engineer that will assist him in determining the incremental flying qualities and/or pilot-performance differences that may be expected between results obtained via ground-based simulation (and, in particular, the six-degree-of-freedom Langley Visual/Motion Simulator (VMS)) and flight tests. Pilot opinion and performance parameters derived from a ground-based simulator and an in-flight simulator are compared for a jet-transport airplane having 32 different longitudinal dynamic response characteristics. The primary pilot tasks were the approach and landing tasks with emphasis on the landing-flare task. The results indicate that, in general, flying qualities results obtained from the ground-based simulator may be considered conservative-especially when the pilot task requires tight pilot control as during the landing flare. The one exception to this, according to the present study, was that the pilots were more tolerant of large time delays in the airplane response on the ground-based simulator. The results also indicated that the ground-based simulator (particularly the Langley VMS) is not adequate for assessing pilot/vehicle performance capabilities (i.e., the sink rate performance for the landing-flare task when the pilot has little depth/height perception from the outside scene presentation).

Comparison of electric field exposure monitoring instrumentation. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bracken, T.D.

1985-06-01

Electric field exposure monitoring instrumentation was compared and evaluated during three days of tests performed in 60-Hz electric fields. A conducting vest exposure meter and a small electric field exposure meter (EFEM) located in a shirt pocket, arm band or hard hat were compared in a series of static and dynamic tests. In some tests, the devices were worn simultaneously without interference to provide separate measures of identical exposure. Tests with stationary subjects wearing the instruments were used to measure the effects of grounding, and to establish the meter response in a standard posture for each subject. Dynamic occupational exposuremore » simulations were used to compare accumulated measurements of exposure between instruments and to compare measurements with predicted exposures. The simulations were based on analysis of the work-related behavior of substation electricians and operators. Electrician's tasks at ground level and in a bucket truck were simulated near an energized test line. A simulated substation inspection was performed in a 230 kV substation. The exposure measurements demonstrated an overall consistency between the meters. The vest demonstrated less intersubject variability and less detailed exposure characterization. Measurements with the shirt pocket EFEM were below those made with the vest and with the EFEM in other locations. Insulation provided by shoe soles appeared to be the largest factor in reducing measured exposures during the substation inspection below those predicted from the unperturbed field. Improvements in meter design and additional measurements are suggested. 11 refs., 20 figs., 28 tabs.« less

Remote Sensing and Remote Control Activities in Europe and America: Part 2--Remote Sensing Ground Stations in Europe,

DTIC Science & Technology

1996-04-08

Development tasks and products of remote sensing ground stations in Europe are represented by the In-Sec Corporation and the Schlumberger Industries Corporation. The article presents the main products of these two corporations.

An Investigation into the Nature of Non-Voiding Contractions Resulting from Detrusor Hyperreflexia in Neurogenic Bladders Following Spinal Cord Injury

DTIC Science & Technology

2014-10-01

SCI) is often occasioned by numerous, rhythmic high pressure non-voiding contractions (NVC) during normal bladder filling. These NVC are...addition to the 16.5 month experiment period) 2c. Final data analysis (data analysis will be ongoing throughout, this will represent the finalization...accomplished. We accomplished Sub-Tasks 2a and 2b. As of 9/2/14, we have completed much of the data analysis (Sub-Task 2c; see below for results). Analysis

Occupational exposure to electric and magnetic fields during work tasks at 110 kV substations in the Tampere region.

PubMed

Korpinen, Leena H; Pääkkönen, Rauno J

2010-04-01

The occupational exposure to electric and magnetic fields during various work tasks at seven 110 kV substations in Finland's Tampere region was studied. The aim was to investigate if the action values (10 kV/m for the E-field and 500 microT for the B-field) of the EU Directive 2004/40/EC were exceeded. Electric and magnetic fields were measured during the following work tasks: (1) walking or operating devices on the ground; (2) working from a service platform; (3) working around the power transformer on the ground or using a ladder; and (4) changing a bulb from a man hoist. In work task 2 "working from a service platform" the measured electric field (maximum value 16.6 kV/m) exceeded 10 kV/m in three cases. In the future it is important to study if the limit value (10 mA/m(2)) of Directive 2004/40/EC is exceeded at 110 kV substations. The occupational 500 microT action value of the magnetic flux density field (B-field) was not exceeded in any working situation.

Water resources of the Big Black River basin, Mississippi

USGS Publications Warehouse

Wasson, B.E.

1971-01-01

Abundant supplies of water of good quality are available in the Big Black River basin from either ground-water or surface-water sources. For 90 percent of the time flow in the lower part of the Big Black River below Pickens is not less than 85 cfs (cubic feet per second), and low flows of more than 5 cfs are available in five of the eastern tributary streams in the upper half of the basin. Chemical quality of water in the streams is excellent, except for impairment caused by pollution at several places. The Big Black River basin is underlain by several thousand feet of clay, silt, sand, gravel, and limestone. This sedimentary material is mostly loose to semiconsolidated and is stratified. The beds dip to the southwest at the rate of 20 to 50 feet per mile. The Big Black River flows southwestward but at a lower gradient; therefore, any specific formation is at a greater depth below the river the farther one goes down stream. The formations crop out in northwest-southeast trending belts. Most of the available ground water is contained in six geologic units; thickness of these individual units ranges from 100 to 1,000 feet. The aquifers overlap to the extent that a well drilled to the base of fresh water will, in most places, penetrate two or more aquifers. Well depths range from less than 10 to 2,400 feet. Water suitable for most needs can be obtained from the aquifers available at most localities. Dissolved-solids content of water within an aquifer increases down the dip. Also, generally the deeper a well is the higher will be the dissolved-solids content of the water. Shallow ground water (less than 200 ft deep) in the basin usually contains about 100 mg/l (milligrams per liter) of dissolved solids. Most water in the basin from more than 2,500 feet below land surface contains m ore than 1,000 mg/l of dissolved solids. In several areas fresh water is deeper than 2,500 feet, but near the mouth of the Big Black River brackish water is only about 300 feet below land surface. Practically all water pumped for man's use in the basin is from the ground (about 11 million gallons per day); however, a small amount of surface water is used for supplemental irrigation of row crops. Wells producing 500 to 1,000 gpm (gallons per minute) are not unusual in the basin. Most of the area is underlain by one or more aquifers from which a properly constructed well could produce as much as 2,000 gpm. All the towns in the area have sufficient ground water available to at least double or triple their ground-water pumpage.

Demands on Finite Cognitive Capacity Cause Infants' Perseverative Errors

ERIC Educational Resources Information Center

Berger, Sarah E.

2004-01-01

This research unites traditionally disparate developmental domains--cognition and locomotion--to examine the classic cognitive issue of the development of inhibition in infancy. In 2 locomotor A-not-B tasks, 13-month-old walking infants inhibited a prepotent response under low task demands (walking on flat ground), but perseverated under increased…

Gravity Wave Energetics Determined From Coincident Space-Based and Ground-Based Observations of Airglow Emissions

NASA Technical Reports Server (NTRS)

2000-01-01

Significant progress was made toward the goals of this proposal in a number of areas during the covered period. Section 5.1 contains a copy of the originally proposed schedule. The tasks listed below have been accomplished: (1) Construction of space-based observing geometry gravity wave model. This model has been described in detail in the paper accompanying this report (Section 5.2). It can simulate the observing geometry of both ground-based, and orbital instruments allowing comparisons to be made between them. (2) Comparisons of relative emission intensity, temperatures, and Krassovsky's ratio for space- and ground-based observing geometries. These quantities are used in gravity wave literature to describe the effects of the waves on the airglow. (3) Rejection of Bates [1992], and Copeland [1994] chemistries for gravity wave modeling purposes. Excessive 02(A(sup 13)(Delta)) production led to overproduction of O2(b(sup 1)(Sigma)), the state responsible for the emission of O2. Atmospheric band. Attempts were made to correct for this behavior, but could not adequately compensate for this. (4) Rejection of MSX dataset due to lack of coincident data, and resolution necessary to characterize the waves. A careful search to identify coincident data revealed only four instances, with only one of those providing usable data. Two high latitude overpasses and were contaminated by auroral emissions. Of the remaining two mid-latitude coincidences, one overflight was obscured by cloud, leaving only one ten minute segment of usable data. Aside from the statistical difficulties involved in comparing measurements taken in this short period, the instrument lacks the necessary resolution to determine the vertical wavelength of the gravity wave. This means that the wave cannot be uniquely characterized from space with this dataset. Since no observed wave can be uniquely identified, model comparisons are not possible.

MANPRINT Methods Monograph: Aiding the Development of Manpower-Based System Evaluation

DTIC Science & Technology

1989-06-01

zone below tree level where threats are known to be (the actual number of threats may vary). Weather conditions are VFR. The helicopter pops up to...12.0 Replace 13.3 Bearing, connecting Inspect 6.2 Replace 6.2 0105 Camshaft Inspect 7.2 Replace 7.2 Cover, cylinder head Inspect .2 (valve cover...matrix to analyze the data and identify task clusters. . Outputs and Use of Cluster Analysis 1. Hierarchical cluster tree (taxonomy) of system tasks will

Does species richness affect fine root biomass and production in young forest plantations?

PubMed

Domisch, Timo; Finér, Leena; Dawud, Seid Muhie; Vesterdal, Lars; Raulund-Rasmussen, Karsten

2015-02-01

Tree species diversity has been reported to increase forest ecosystem above-ground biomass and productivity, but little is known about below-ground biomass and production in diverse mixed forests compared to single-species forests. For testing whether species richness increases below-ground biomass and production and thus complementarity between forest tree species in young stands, we determined fine root biomass and production of trees and ground vegetation in two experimental plantations representing gradients in tree species richness. Additionally, we measured tree fine root length and determined species composition from fine root biomass samples with the near-infrared reflectance spectroscopy method. We did not observe higher biomass or production in mixed stands compared to monocultures. Neither did we observe any differences in tree root length or fine root turnover. One reason for this could be that these stands were still young, and canopy closure had not always taken place, i.e. a situation where above- or below-ground competition did not yet exist. Another reason could be that the rooting traits of the tree species did not differ sufficiently to support niche differentiation. Our results suggested that functional group identity (i.e. conifers vs. broadleaved species) can be more important for below-ground biomass and production than the species richness itself, as conifers seemed to be more competitive in colonising the soil volume, compared to broadleaved species.

Large-scale sequestration of atmospheric carbon via plant roots in natural and agricultural ecosystems: why and how.

PubMed

Kell, Douglas B

2012-06-05

The soil holds twice as much carbon as does the atmosphere, and most soil carbon is derived from recent photosynthesis that takes carbon into root structures and further into below-ground storage via exudates therefrom. Nonetheless, many natural and most agricultural crops have roots that extend only to about 1 m below ground. What determines the lifetime of below-ground C in various forms is not well understood, and understanding these processes is therefore key to optimising them for enhanced C sequestration. Most soils (and especially subsoils) are very far from being saturated with organic carbon, and calculations show that the amounts of C that might further be sequestered (http://dbkgroup.org/carbonsequestration/rootsystem.html) are actually very great. Breeding crops with desirable below-ground C sequestration traits, and exploiting attendant agronomic practices optimised for individual species in their relevant environments, are therefore important goals. These bring additional benefits related to improvements in soil structure and in the usage of other nutrients and water.

Accelerated Metals Development by Computation

DTIC Science & Technology

2008-02-01

6 Task 2………………………………………………………………………………….21 Task 3………………………………………………………………………………….32 Task 4 ………………………………………………………………………………….59 Task 5...and DISCUSSION 1. Introduction 2. Methods, Assumptions, Procedures 3. Results 4 . Discussion 5. Conclusions 6 . Recommendations 7. References 8...Tasks 1, 2, 3, 4 and 8 (see list below). Phase two involved the initiation of three additional tasks which evolved into Tasks 5, 6 , and 7. Phase 3

Prediction of atmospheric δ 13CO 2 using fossil plant tissues

DOE Office of Scientific and Technical Information (OSTI.GOV)

A. Hope Jahren; Arens, Nan Crystal; Harbeson, Stephanie A.

2008-06-30

To summarize the content: we presented the results of laboratory experiments designed to quantify the relationship between plant tissue δ 13C and δ 13CO 2 values under varying environmental conditions, including differential pCO 2 ranging from 1 to 3 times today’s levels. As predicted, plants grown under elevated pCO2 showed increased average biomass compared to controls grown at the same temperature. Across a very large range in δ 13Ca (≈ 24 ‰) and pCO 2 (≈ 740 ppmv) we observed a consistent correlation between δ13Ca and δ 13Cp (p<0.001). We show an average isotopic depletion of -25.4 ‰ for above-groundmore » tissue and -23.2 ‰ for below-ground tissue of Raphanus sativus L. relative to the composition of the atmosphere under which it formed. For both above- and below-ground tissue, grown at both ~23 °C and ~29 °C, correlation was strong and significant (r2 ≥ 0.98, p<0.001); variation in pCO 2 level had little or no effect on this relationship.« less

Ground-Water Quality Data in the Southern Sierra Study Unit, 2006 - Results from the California GAMA Program

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2007-01-01

Ground-water quality in the approximately 1,800 square-mile Southern Sierra study unit (SOSA) was investigated in June 2006 as part of the Statewide Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Southern Sierra study was designed to provide a spatially unbiased assessment of raw ground-water quality within SOSA, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from fifty wells in Kern and Tulare Counties. Thirty-five of the wells were selected using a randomized grid-based method to provide statistical representation of the study area, and fifteen were selected to evaluate changes in water chemistry along ground-water flow paths. The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, pharmaceutical compounds, and wastewater-indicator compounds], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), and 1,2,3-trichloropropane (1,2,3-TCP)], naturally occurring inorganic constituents [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water], and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, and samples for matrix spikes) were collected for approximately one-eighth of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control information resulted in censoring of less than 0.2 percent of the data collected for ground-water samples. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. VOCs and pesticides were detected in less than one-third of the grid wells, and all detections in samples from SOSA wells were below health-based thresholds. All detections of trace elements and nutrients in samples from SOSA wells were below health-based thresholds, with the exception of four detections of arsenic that were above the USEPA maximum contaminant level (MCL-US) and one detection of boron that was above the CDPH notification level (NL-CA). All detections of radioactive constituents were below health-based thresholds, although four samples had activities of radon-222 above the proposed MCL-US. Most of the samples from SOSA wells had concentrations of major elements, total dissolved solids, and trace elements below the non-enforceable thresholds set for aesthetic concerns. A few samples contained iron, manganese, or total dissolved solids at concentrations above the SMCL-CA thresholds.

Effect of an Invasive Grass on Ambient Rates of Decomposition and Microbial Community Structure: A Search for Causality

USDA-ARS?s Scientific Manuscript database

In sutu decomposition of above and below ground plant biomass of the native grass species Andropogon glmoeratus (Walt.) B.S.P and exotic Imperata cylindrica (L.) Beauv. (cogongrass) was investigated using litter bags over the course of a 12 month period. The above and below ground biomass of the inv...

Below- and above-ground effects of deadwood and termites in plantation forests

Treesearch

Michael D. Ulyshen; Richard Shefferson; Scott Horn; Melanie K. Taylor; Bryana Bush; Cavell Brownie; Sebastian Seibold; Michael S. Strickland

2017-01-01

Deadwood is an important legacy structure in managed forests, providing continuity in shelter and resource availability for many organisms and acting as a vehicle by which nutrients can be passed from one stand to the next following a harvest. Despite existing at the interface between below- and above-ground systems, however, much remains unknown about the role woody...

Genetic Control of Water and Nitrate Capture and Their Use Efficiency in Lettuce (Lactuca sativa L.)

PubMed Central

Kerbiriou, Pauline J.; Maliepaard, Chris A.; Stomph, Tjeerd Jan; Koper, Martin; Froissart, Dorothee; Roobeek, Ilja; Lammerts Van Bueren, Edith T.; Struik, Paul C.

2016-01-01

Robustness in lettuce, defined as the ability to produce stable yields across a wide range of environments, may be associated with below-ground traits such as water and nitrate capture. In lettuce, research on the role of root traits in resource acquisition has been rather limited. Exploring genetic variation for such traits and shoot performance in lettuce across environments can contribute to breeding for robustness. A population of 142 lettuce cultivars was evaluated during two seasons (spring and summer) in two different locations under organic cropping conditions, and water and nitrate capture below-ground and accumulation in the shoots were assessed at two sampling dates. Resource capture in each soil layer was measured using a volumetric method based on fresh and dry weight difference in the soil for soil moisture, and using an ion-specific electrode for nitrate. We used these results to carry out an association mapping study based on 1170 single nucleotide polymorphism markers. We demonstrated that our indirect, high-throughput phenotyping methodology was reliable and capable of quantifying genetic variation in resource capture. QTLs for below-ground traits were not detected at early sampling. Significant marker-trait associations were detected across trials for below-ground and shoot traits, in number and position varying with trial, highlighting the importance of the growing environment on the expression of the traits measured. The difficulty of identifying general patterns in the expression of the QTLs for below-ground traits across different environments calls for a more in-depth analysis of the physiological mechanisms at root level allowing sustained shoot growth. PMID:27064203

Effects of nitrogen deposition on carbon cycle in terrestrial ecosystems of China: A meta-analysis.

PubMed

Chen, Hao; Li, Dejun; Gurmesa, Geshere A; Yu, Guirui; Li, Linghao; Zhang, Wei; Fang, Huajun; Mo, Jiangming

2015-11-01

Nitrogen (N) deposition in China has increased greatly, but the general impact of elevated N deposition on carbon (C) dynamics in Chinese terrestrial ecosystems is not well documented. In this study we used a meta-analysis method to compile 88 studies on the effects of N deposition C cycling on Chinese terrestrial ecosystems. Our results showed that N addition did not change soil C pools but increased above-ground plant C pool. A large decrease in below-ground plant C pool was observed. Our result also showed that the impacts of N addition on ecosystem C dynamics depend on ecosystem type and rate of N addition. Overall, our findings suggest that 1) decreased below-ground plant C pool may limit long-term soil C sequestration; and 2) it is better to treat N-rich and N-limited ecosystems differently in modeling effects of N deposition on ecosystem C cycle. Copyright © 2015 Elsevier Ltd. All rights reserved.

Differences in Neuromuscular Strategies Between Landing and Cutting Tasks in Female Basketball and Soccer Athletes

PubMed Central

Cowley, Hanni R; Ford, Kevin R; Myer, Gregory D; Kernozek, Thomas W; Hewett, Timothy E

2006-01-01

Context: High school female athletes are most likely to sustain a serious knee injury during soccer or basketball, 2 sports that often involve a rapid deceleration before a change of direction or while landing from a jump. Objective: To determine if female high school basketball and soccer players show neuromuscular differences during landing and cutting tasks and to examine neuromuscular differences between tasks and between dominant and nondominant sides. Design: A 3-way mixed factorial design investigating the effects of sport (basketball, soccer), task (jumping, cutting), and side (dominant, nondominant). Setting: Laboratory. Patients or Other Participants: Thirty high school female athletes who listed either basketball or soccer as their only sport of participation (basketball: n = 15, age = 15.1 ± 1.7 years, experience = 6.9 ± 2.2 years, height = 165.3 ± 7.9 cm, mass = 61.8 ± 9.3 kg; soccer: n = 15, age = 14.8 ± 0.8 years, experience = 8.8 ± 2.5 years, height = 161.8 ± 4.1 cm, mass = 54.6 ± 7.6 kg). Main Outcome Measure(s): Ground reaction forces, stance time, valgus angles, and valgus moments were assessed during (1) a drop vertical jump with an immediate maximal vertical jump and (2) an immediate side-step cut at a 45° angle. Results: Basketball athletes had greater ground reaction forces (P < .001) and decreased stance time (P < .001) during the drop vertical jump, whereas soccer players had greater ground reaction forces (P <.001) and decreased stance time (P < .001) during the cut. Subjects in both sports had greater valgus angles (initial contact and maximum, P = .02 and P = .012, respectively) during cutting than during the drop vertical jump. Greater valgus moments (P = .006) were noted on the dominant side during cutting. Conclusions: Our subjects demonstrated differences in ground reaction forces and stance times during 2 movements associated with noncontact anterior cruciate ligament injuries. Knee valgus moment and angle were significantly influenced by the type of movement performed. Sport-specific neuromuscular training may be warranted, with basketball players focusing on jumping and landing and soccer players focusing on unanticipated cutting maneuvers. PMID:16619097

Effects of migratory geese on plant communities of an Alaskan salt marsh

USGS Publications Warehouse

Zacheis, Amy B.; Hupp, Jerry W.; Ruess, Roger W.

2001-01-01

1. We studied the effects of lesser snow geese (Anser caerulescens caerulescens) and Canada geese (Branta canadensis) on two salt marsh plant communities in Cook Inlet, Alaska, a stopover area used during spring migration. From 1995 to 1997 we compared plant species composition and biomass on plots where geese were excluded from feeding with paired plots where foraging could occur. 2. Foraging intensity was low (650-1930 goose-days km-2) compared to other goose-grazing systems. 3. Canada geese fed mainly on above-ground shoots of Triglochin maritimum, Puccinellia spp. and Carex ramenskii, whereas the majority of the snow goose diet consisted of below-ground tissues of Plantago maritima and Triglochin maritimum. 4. Plant communities responded differently to goose herbivory. In the sedge meadow community, where feeding was primarily on above-ground shoots, there was no effect of grazing on the dominant species Carex ramenskii and Triglochin maritimum. In the herb meadow community, where snow geese fed on Plantago maritima roots and other below-ground tissues, there was a difference in the relative abundance of plant species between treatments. Biomass of Plantago maritima and Potentilla egedii was lower on grazed plots compared with exclosed, whereas biomass of Carex ramenskii was greater on grazed plots. There was no effect of herbivory on total standing crop biomass in either community. The variable effect of herbivory on Carex ramenskii between communities suggests that plant neighbours and competitive interactions are important factors in a species' response to herbivory. In addition, the type of herbivory (above- or below-ground) was important in determining plant community response to herbivory. 5. Litter accumulation was reduced in grazed areas compared with exclosed in both communities. Trampling of the previous year's litter into the soil surface by geese incorporated more litter into soils in grazed areas. 6. This study illustrates that even light herbivore pressure can alter plant communities and affect forage availability.

Charge Order in (TMTTF)2TaF6 by Infrared Spectroscopy

NASA Astrophysics Data System (ADS)

Oka, Yuki; Matsunaga, Noriaki; Nomura, Kazushige; Kawamoto, Atsuhi; Yamamoto, Kaoru; Yakushi, Kyuya

2015-11-01

We have performed infrared spectroscopy in (TMTTF)2TaF6 (TMTTF: tetramethyltetrathiafulvalene) to investigate the relationship between the charge order (CO) state and the antiferromagnetic (AF) insulating ground state. A clear peak splitting corresponding to the charge disproportionation was observed below the CO transition temperature. We estimated the degree of charge disproportionation, Δρ = ρrich - ρpoor, as 0.28e from the peak splitting and found that the CO state coexists with the AF state and there is no charge redistribution below the AF transition.

Simulation of ground-water flow in the Potomac-Raritan-Magothy aquifer system near the Defense Supply Center Philadelphia, and the Point Breeze Refinery, southern Philadelphia County, Pennsylvania

USGS Publications Warehouse

Schreffler, Curtis L.

2001-01-01

Ground-water flow in the Potomac-Raritan- Magothy aquifer system (PRM) in south Philadelphia and adjacent southwestern New Jersey was simulated by use of a three-dimensional, seven-layer finite-difference numerical flow model. The simulation was run from 1900, which was prior to groundwater development, through 1995 with 21 stress periods. The focus of the modeling was on a smaller area of concern in south Philadelphia in the vicinity of the Defense Supply Center Philadelphia (DSCP) and the Point Breeze Refinery (PBR). In order to adequately simulate the ground-water flow system in the area of concern, a much larger area was modeled that included parts of New Jersey where significant ground-water withdrawals, which affect water levels in southern Philadelphia, had occurred in the past. At issue in the area of concern is a hydrocarbon plume of unknown origin and time of release.The ground-water-flow system was simulated to estimate past water-level altitudes in and near the area of concern and to determine the effect of the Packer Avenue sewer, which lies south of the DSCP, on the ground-water-flow system. Simulated water-level altitudes for the lower sand unit of the PRM on the DSCP prior to 1945 ranged from pre-development, unstressed altitudes to 3 feet below sea level. Simulated water-level altitudes for the lower sand unit ranged from 3 to 7 feet below sea level from 1946 to 1954, from 6 to 10 feet below sea level from 1955 to 1968, and from 9 to 11 feet below sea level from 1969 to 1978. The lowest simulated water-level altitude on the DSCP was 10.69 feet below sea level near the end of 1974. Model simulations indicate ground water was infiltrating the Packer Avenue sewer prior to approximately 1947 or 1948. Subsequent to that time, simulated ground-water-level altitudes were lower than the bottom of the sewer.

A nonlinear merging method of analog and photon signals for CO2 detection in lower altitudes using differential absorption lidar

NASA Astrophysics Data System (ADS)

Qi, Zhong; Zhang, Teng; Han, Ge; Li, Dongcang; Ma, Xin; Gong, Wei

2017-04-01

The current acquisition system of a lidar detects return signals in two modes (i.e., analog and photon counting); resulting in the lower (below 1500 m) and upper (higher than 1100 m) atmospheric parameters need analog and photon counting signal to retrieve, respectively. Hence, a lidar cannot obtain a continuous column of the concentrations of atmospheric components. For carbon cycle studies, the range-resolved concentration of atmospheric CO2 in the lower troposphere (below 1500 m) is one of the most significant parameters that should be determined. This study proposes a novel gluing method that merges the CO2 signal detected by ground-based DIAL in the lower troposphere. Through simulation experiments, the best uniform approximation polynomial theorem is utilized to determine the transformation coefficient to correlate signals from the different modes perfectly. The experimental results (both simulation experiments and actual measurement of signals) show that the proposed method is suitable and feasible for merging data in the region below 1500 m. Hence, the photon-counting signals whose SNRs are higher than those of the analog signals can be used to retrieve atmospheric parameters at an increased near range, facilitating atmospheric soundings using ground-based lidar in various fields.

Laser pulse control of ultrafast heterogeneous electron transfer: a computational study.

PubMed

Wang, Luxia; May, Volkhard

2004-10-22

Laser pulse control of the photoinduced 90 fs charge injection from perylene into the conduction band of TiO2 is studied theoretically. The approach accounts for the electronic-ground state of the dye, the first excited state, the ionized state formed after charge injection, and the continuum of the electronic states in the conduction band, all defined vs a single reaction coordinate. To address different control tasks optimal control theory is combined with a full quantum dynamical description of the electron-vibrational motion accompanying the charge injection process. First it is proved in which way the charge injection time can be changed by tailored laser pulses. In a second step a pump-dump scheme from the perylene ground state to the first excited electronic state and back to the ground state is discussed. Because of the strong coupling of the excited perylene state to the band continuum of TiO2 this control task is more suited to an experimental test than the direct control of the charge injection.

Competitive responses of seedlings and understory plants in longleaf pine woodlands: separating canopy influences above and below ground

Treesearch

Stephen D. Pecot; Robert J. Mitchell; Brian J. Palik; Barry Moser; J. Kevin Hiers

2007-01-01

A trenching study was used to investigate above- and below-ground competition in a longleaf pine (Pinus palustris P. Mill.) woodland. Trenched and nontrenched plots were replicated in the woodland matrix, at gap edges, and in gap centers representing a range of overstory stocking. One-half of each plot received a herbicide treatment to remove the...

Microgravity Science and Applications. Program Tasks and Bibliography for FY 1993

NASA Technical Reports Server (NTRS)

1994-01-01

An annual report published by the Microgravity Science and Applications Division (MSAD) of NASA is presented. It represents a compilation of the Division's currently-funded ground, flight and Advanced Technology Development tasks. An overview and progress report for these tasks, including progress reports by principal investigators selected from the academic, industry and government communities, are provided. The document includes a listing of new bibliographic data provided by the principal investigators to reflect the dissemination of research data during FY 1993 via publications and presentations. The document also includes division research metrics and an index of the funded investigators. The document contains three sections and three appendices: Section 1 includes an introduction and metrics data, Section 2 is a compilation of the task reports in an order representative of its ground, flight or ATD status and the science discipline it represents, and Section 3 is the bibliography. The three appendices, in the order of presentation, are: Appendix A - a microgravity science acronym list, Appendix B - a list of guest investigators associated with a biotechnology task, and Appendix C - an index of the currently funded principal investigators.

Optical sensor nanoparticles in artificial sediments--a new tool to visualize O2 dynamics around the rhizome and roots of seagrasses.

PubMed

Koren, Klaus; Brodersen, Kasper E; Jakobsen, Sofie L; Kühl, Michael

2015-02-17

Seagrass communities provide important ecosystems services in coastal environments but are threatened by anthropogenic impacts. Especially the ability of seagrasses to aerate their below-ground tissue and immediate rhizosphere to prevent sulfide intrusion from the surrounding sediment is critical for their resilience to environmental disturbance. There is a need for chemical techniques that can map the O2 distribution and dynamics in the seagrass rhizosphere upon environmental changes and thereby identify critical stress thresholds of e.g. water flow, turbidity, and O2 conditions in the water phase. In a novel experimental approach, we incorporated optical O2 sensor nanoparticles into a transparent artificial sediment matrix consisting of pH-buffered deoxygenated sulfidic agar. Seagrass growth and photosynthesis was not inhibited in the experimental setup when the below-ground biomass was immobilized in the artificial sulfidic sediment with nanoparticles and showed root growth rates (∼ 5 mm day(-1)) and photosynthetic quantum yields (∼ 0.7) comparable to healthy seagrasses in their natural habitat. We mapped the real-time below ground O2 distribution and dynamics in the whole seagrass rhizosphere during experimental manipulation of light exposure and O2 content in the overlaying water. Those manipulations showed that oxygen release from the belowground tissue is much higher in light as compared to darkness and that water column hypoxia leads to diminished oxygen levels around the rhizome/roots. Oxygen release was visualized and analyzed on a whole rhizosphere level, which is a substantial improvement to existing methods relying on point measurements with O2 microsensors or partial mapping of the rhizosphere in close contact with a planar O2 optode. The combined use of optical nanoparticle-based sensors with artificial sediments enables imaging of chemical microenvironments in the rhizosphere of aquatic plants at high spatiotemporal resolution with a relatively simple experimental setup and thus represents a significant methodological advancement for studies of environmental impacts on aquatic plant ecophysiology.

Effects of above- and below-ground competition from shrubs on photosynthesis, transpiration and growth in Quercus robur L

Treesearch

Anna M. Jensen; Magnus Lof; Emile S. Gardiner

2011-01-01

For a tree seedling to successfully establish in dense shrubbery, it must maintain function under heterogeneous resource availability. We evaluated leaf-level acclimation in photosynthetic capacity, seedling-level transpiration, and seedling morphology and growth to gain an understanding of the effects of above- and below-ground competition on Quercus robur seedlings....

Magnetic ground state of the layered honeycomb compound Na2Co2TeO6

NASA Astrophysics Data System (ADS)

Bera, A. K.; Yusuf, S. M.

2018-04-01

The magnetic correlations in the 2D layered honeycomb compound Na2Co2TeO6 has been investigated. The temperature dependent susceptibility curve reveals a transition to the magnetically ordered state at TN ˜ 25 K. The temperature dependent neutron diffraction study confirms an antiferromagnetic ordering below TN. The magnetic ground state is determined to be a zigzag antiferromagnet that appears due to competing exchange interactions beyond nearest neighbors. The moments align along the crystallographic b axis with reduced ordered magnetic moment values of 2.72(2) μB/Co2+ and 2.52(3) μB/Co2+ for two Co sites, respectively. In comparison to the theoretical phase diagram the determined zigzag antiferromagnetic ground state suggests that the compound Na2Co2TeO6 is situated in the proximity to the quantum spin liquid state in the phase diagram.

Leaf and fine root carbon stocks and turnover are coupled across Arctic ecosystems.

PubMed

Sloan, Victoria L; Fletcher, Benjamin J; Press, Malcolm C; Williams, Mathew; Phoenix, Gareth K

2013-12-01

Estimates of vegetation carbon pools and their turnover rates are central to understanding and modelling ecosystem responses to climate change and their feedbacks to climate. In the Arctic, a region containing globally important stores of soil carbon, and where the most rapid climate change is expected over the coming century, plant communities have on average sixfold more biomass below ground than above ground, but knowledge of the root carbon pool sizes and turnover rates is limited. Here, we show that across eight plant communities, there is a significant positive relationship between leaf and fine root turnover rates (r(2) = 0.68, P < 0.05), and that the turnover rates of both leaf (r(2) = 0.63, P < 0.05) and fine root (r(2) = 0.55, P < 0.05) pools are strongly correlated with leaf area index (LAI, leaf area per unit ground area). This coupling of root and leaf dynamics supports the theory of a whole-plant economics spectrum. We also show that the size of the fine root carbon pool initially increases linearly with increasing LAI, and then levels off at LAI = 1 m(2) m(-2), suggesting a functional balance between investment in leaves and fine roots at the whole community scale. These ecological relationships not only demonstrate close links between above and below-ground plant carbon dynamics but also allow plant carbon pool sizes and their turnover rates to be predicted from the single readily quantifiable (and remotely sensed) parameter of LAI, including the possibility of estimating root data from satellites. © 2013 John Wiley & Sons Ltd.

76 FR 51257 - First-Class Package Service

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-18

... Ground, and Bound Printed Matter prices. * * * * * * * * 2.0 Additional Physical Standards by Class of... ``PRSRT'') First-Class Package'' (or ``PKG'') must be printed as part of; directly below; or to the left... follows:] b. * * * labeling: * * * * * 2. Line 2: ``FC PARCELS 3D.'' [Revise item 4.4c2 by changing ``FCM...

Sources of Below-Ground Respired Carbon in a Northern Minnesota Ombrotrophic Spruce Bog and the Influence of Heating Manipulations.

NASA Astrophysics Data System (ADS)

Guilderson, T. P.; McFarlane, K. J.; McNicol, G.; Hanson, P. J.; Chanton, J.; Wilson, R.; Bosworth, R.; Singleton, M. J.

2015-12-01

A significant uncertainty in future land-surface carbon budgets is the response of wetlands to climate change. A related question is the future net climate (radiative) forcing impact due to ecosystem and environmental change in wetlands. Active wetlands emit both CO2 and CH4 to the atmosphere. CH4 is, over a few decades, a much more potent greenhouse gas than CO2 whereas as a consequence of a much longer atmospheric lifetime, CO2 has a longer 'tail' to its influence. Whether wetlands are a net source or sink of atmospheric carbon under future climate change will depend on the response of the ecosystem to rising temperatures and elevated CO2. The largest uncertainty in future wetland budgets, and its climate forcing, is the stability of the large belowground carbon stocks, often in the form of peat, and the partitioning of CO2 and CH4released via ecosystem respiration. We have characterized the isotopic signatures (14,13C of CO2 and CH4, D-CH4) of the respired carbon used for the production of CO2 and CH4 from the DOE Spruce and Peatland Responses Under Climatic and Environmental Change (SPRUCE) site in the Marcell Experimental Forest, which contains replicated mesocosm manipulations including above/below ground warming and elevated CO2. Deep warming (1-2 m) was initiated in July of 2014 and above ground heating will be initiated in July 2015. Comparison of the respired CO2 and CH4with recently fixed photosynthate, below-ground peat (up to 11,000 years old), and dissolved organic carbon allow us to determine the primary substrates used by the microbial community. Control and pre-perturbed plots are characterized by the consumption and respiration of recently fixed photosynthate and recent (few years to 15 yr) carbon. Although CH4 fluxes have begun to respond to deep-heating, the source of carbon remains similar in the control and perturbed plots. Respired CO2 remains consistent with being sourced from carbon only a few years old. We will present additional data collected in July, August, and September 2015 which will include the combined influence of above and belowground heating.

Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands.

PubMed

Setoh, Peipei; Scott, Rose M; Baillargeon, Renée

2016-11-22

When tested with traditional false-belief tasks, which require answering a standard question about the likely behavior of an agent with a false belief, children perform below chance until age 4 y or later. When tested without such questions, however, children give evidence of false-belief understanding much earlier. Are traditional tasks difficult because they tap a more advanced form of false-belief understanding (fundamental-change view) or because they impose greater processing demands (processing-demands view)? Evidence that young children succeed at traditional false-belief tasks when processing demands are reduced would support the latter view. In prior research, reductions in inhibitory-control demands led to improvements in young children's performance, but often only to chance (instead of below-chance) levels. Here we examined whether further reductions in processing demands might lead to success. We speculated that: (i) young children could respond randomly in a traditional low-inhibition task because their limited information-processing resources are overwhelmed by the total concurrent processing demands in the task; and (ii) these demands include those from the response-generation process activated by the standard question. This analysis suggested that 2.5-y-old toddlers might succeed at a traditional low-inhibition task if response-generation demands were also reduced via practice trials. As predicted, toddlers performed above chance following two response-generation practice trials; toddlers failed when these trials either were rendered less effective or were used in a high-inhibition task. These results support the processing-demands view: Even toddlers succeed at a traditional false-belief task when overall processing demands are reduced.

Conversational Grounding in Younger and Older Adults: The Effect of Partner Visibility and Referent Abstractness in Task-Oriented Dialogue

ERIC Educational Resources Information Center

Lysander, Katya; Horton, William S.

2012-01-01

Many communicative situations present interlocutors with the opportunity to use multiple modalities to establish shared perspectives on conversational referents, a process known as grounding. In the current study, we use a card-matching task to examine how conversational grounding in younger and older adults is influenced both by direct visual…

Advanced Wireless Integrated Navy Network - AWINN

DTIC Science & Technology

2005-06-30

de Sousa, GRA (5/15/05-6/30/05) George C. Hadjichristofi, GRA (4/1/05-5/14/05) Unghee Lee, GRA (33% for 4/1/05-5/14/05, 100% for 5/15/05-6/30/05...and initial implementation of test bed conversion to support Internet Protocol version 6 (IPv6). In this section, we also report on accomplishments in...below. 2.1.2 Task Activities for the Period Subtask 2. la Policy-based Quality of Service Task Obiective: The objectives of this subtask are to

Mines and Demolitions

DTIC Science & Technology

1974-04-22

effectiveness of these mineb is determined by the Wound Ballistics Branch of the U. S. Army Balliatics Research ’Laboratories, Aberden Proving Ground , KI...Ia. P ROORAM EL EME~dT.PAOj ECT. TASK( * AREA & WORK UNIT NIAMOERS U. S. Array AbrenP.:oing Ground (STEaP-Htr-H) Aberdeen Proving Srouad, Ltd. 2 005...to th~a publiratioa should bp~ forwarded to Comaander. U. S. Army Test and Evaluation Command, ATTN: D RSTE-M.S, Abevdt.,en Proving Ground . Md. 21005

Development of a Geospatial Data-Sharing Method for Unmanned Vehicles Based on the Joint Architecture for Unmanned Systems (JAUS)

DTIC Science & Technology

2005-08-01

the Office of the Secretary of Defense chartered the Joint Architecture for Unmanned Ground Systems ( JAUGS ) Working Group to address these concerns...The JAUGS Working Group was tasked with developing an initial standard for interoperable unmanned ground systems. In 2002, the charter of the... JAUGS Working Group was 1 2 modified such that their efforts would extend to all unmanned systems, not only ground systems. The standard was

Mind the Roots: Phenotyping Below-Ground Crop Diversity and Its Influence on Final Yield

NASA Astrophysics Data System (ADS)

Nieters, C.; Guadagno, C. R.; Lemli, S.; Hosseini, A.; Ewers, B. E.

2017-12-01

Changes in global climate patterns and water regimes are having profound impacts on worldwide crop production. An ever-growing population paired with increasing temperatures and unpredictable periods of severe drought call for accurate modeling of future crop yield. Although novel approaches are being developed in high-throughput, above-ground image phenotyping, the below-ground plant system is still poorly phenotyped. Collection of plant root morphology and hydraulics are needed to inform mathematical models to reliably estimate yields of crops grown in sub-optimal conditions. We used Brassica rapa to inform our model as it is a globally cultivated crop with several functionally diverse cultivars. Specifically, we use 7 different accessions from oilseed (R500 and Yellow Sarson), leafy type (Pac choi and Chinese cabbage), a vegetable turnip, and two Wisconsin Fast Plants (Imb211 and Fast Plant self-compatible), which have shorter life cycles and potentially large differences in allocation to roots. Bi-weekly, we harvested above and below-ground biomass to compare the varieties in terms of carbon allocation throughout their life cycle. Using WinRhizo software, we analyzed root system length and surface area to compare and contrast root morphology among cultivars. Our results confirm that root structural characteristics are crucial to explain plant water use and carbon allocation. The root:shoot ratio reveals a significant (p < 0.01) difference among crop accession. To validate the procedure across different varieties and life stages we also compared surface area results from the image-based technology to dry biomass finding a strong linear relationship (R2= 0.85). To assess the influence of a diverse above-ground morphology on the root system we also measured above-ground anatomical and physiological traits such as gas exchange, chlorophyll content, and chlorophyll a fluorescence. A thorough analysis of the root system will clarify carbon dynamics and hydraulics at the whole-plant level, improving final yield predictions.

Combined effects of agrochemicals and ecosystem services on crop yield across Europe.

PubMed

Gagic, Vesna; Kleijn, David; Báldi, András; Boros, Gergely; Jørgensen, Helene Bracht; Elek, Zoltán; Garratt, Michael P D; de Groot, G Arjen; Hedlund, Katarina; Kovács-Hostyánszki, Anikó; Marini, Lorenzo; Martin, Emily; Pevere, Ines; Potts, Simon G; Redlich, Sarah; Senapathi, Deepa; Steffan-Dewenter, Ingolf; Świtek, Stanislaw; Smith, Henrik G; Takács, Viktória; Tryjanowski, Piotr; van der Putten, Wim H; van Gils, Stijn; Bommarco, Riccardo

2017-11-01

Simultaneously enhancing ecosystem services provided by biodiversity below and above ground is recommended to reduce dependence on chemical pesticides and mineral fertilisers in agriculture. However, consequences for crop yield have been poorly evaluated. Above ground, increased landscape complexity is assumed to enhance biological pest control, whereas below ground, soil organic carbon is a proxy for several yield-supporting services. In a field experiment replicated in 114 fields across Europe, we found that fertilisation had the strongest positive effect on yield, but hindered simultaneous harnessing of below- and above-ground ecosystem services. We furthermore show that enhancing natural enemies and pest control through increasing landscape complexity can prove disappointing in fields with low soil services or in intensively cropped regions. Thus, understanding ecological interdependences between land use, ecosystem services and yield is necessary to promote more environmentally friendly farming by identifying situations where ecosystem services are maximised and agrochemical inputs can be reduced. © 2017 John Wiley & Sons Ltd/CNRS.

The impact of forest structure on near-ground temperatures during two years of contrasting temperature extremes

Treesearch

Brian E. Potter; Ronald M. Teclaw; John C. Zasada

2001-01-01

The thermal environment of clear-cut, partially cut, and uncut forest sites in northern Wisconsin are examined for a warm year and a cool year. Temperatures at 0.5 m above and 0.05m below ground, as well as base 5 degree C heat sums are computed for each site between May and September and differences between cut and uncut sites compared for the 2 years. differences in...

Monitoring for PCBs at the Pilot Plant Complex, Aberdeen Proving Ground

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schneider, J.F.; O`Neill, H.J.; Cohut, V.J.

1995-07-01

The US Army`s Aberdeen Proving Ground has been a test site for a variety of munitions, including chemical warfare agents. The Pilot Plant Complex (PPC) at Aberdeen was the site of the development, manufacture, storage, and disposal of a number of chemical warfare agents. The objective of this study was to determine if there is polychlorinated biphenyl (PCB) contamination in the PPC. The results of screening done by Argonne indicate that PCBs in the air of the PPC are well below acceptable levels. The total PCB burden of the surfaces in the PPC appears to be well below the 50-ppMmore » regulatory level. However, the study identified contaminated floor surfaces that exceed the acceptable level of 10 {mu}g/100 cm{sup 2} for a workplace. Areas in Building E5618 exceed 1,000 {mu}g/100 cm{sup 2}, with a high reading of 21,100 {mu}g/100 cm{sup 2} in room C103. Building E5625 has several areas where PCBs exceed 100 {mu}g/cm{sup 2}.« less

Condensed-Phase Processes during Solid Propellant Combustion. 3. Preliminary Depth-Profiling Studies on XM39, JA2, M9, M30, and HMX2

DTIC Science & Technology

1994-01-01

are listed in Schroeder et al. (1992). Wilmot et al. (1981) and Sharma et al. (1991) describe the chemical analysis of the burned surface of nitrate...below the surface (spectrum(b)) and are totally absent from the spectrum(c) of the region 40-80 pm below the surface CF (spectrum(d)). This suggests...Proving Ground, MD, May 1992. (AD-A250 799) Sharma, J., G. B. Wilmot , A. A. Campolattaro, and F. Santiago. "XPS Study of Condensed Phase Combustion in

Stream simulation in an analog model of the ground-water system on Long Island, New York

USGS Publications Warehouse

Harbaugh, Arlen W.; Getzen, Rufus T.

1977-01-01

The stream circuits of an electric analog model of the ground-water system of Long Island were modified to more accurately represent the relationahip between streamflow and ground-water levels. Assumptions for use of the revised circuits are (1) that streams are strictly gaining, and (2) that ground-water seepage into the streams is proportional to the difference between streambed elevation and the average water-table elevation near the stream. No seepage into streams occurs when ground-water levels drop below the streambed elevation. Regional simulation of the 1962-68 drought on Long Island was significantly improved by use of the revised stream circuits.

Glaciation and regional ground-water flow in the Fennoscandian Shield: Site 94

USGS Publications Warehouse

Provost, Alden M.; Voss, Clifford I.; Neuzil, C.E.

1998-01-01

Results from a regional-scale ground-water flow model of the Fennoscandian shield suggest that ground-water flow is strongly affected by surface conditions associated with climatic change and glaciation. The model was used to run a series of numerical simulations of variable-density ground-water flow in a 1500-km-long and approximately 10-km-deep cross-section that passes through southern Sweden. Ground-water flow and shield brine transport in the cross-sectional model are controlled by an assumed time evolution of surface conditions over the next 140 ka. Simulations show that, under periglacial conditions, permafrost may locally or extensively impede the free recharge or discharge of ground water. Below cold-based glacial ice, no recharge or discharge of ground water occurs. Both of these conditions result in the settling of shield brine and consequent freshening of near-surface water in areas of natural discharge blocked by permafrost. The presence of warm-based ice with basal melting creates a potential for ground-water recharge rates much larger than under present, ice-free conditions. Recharging basal meltwater can reach depths of a few kilometers in a few thousand years. The vast majority of recharged water is accommodated through storage in the volume of bedrock below the local area of recharge; regional (lateral) redistribution of recharged water by subsurface flow is minor over the duration of a glacial advance (~10 ka). During glacial retreat, the weight of the ice overlying a given surface location decreases, and significant upward flow of ground water may occur below the ice sheet due to pressure release, despite the continued potential for recharge of basal meltwater. Excess meltwater must exit from below the glacier through subglacial cavities and channels. Subsurface penetration of meltwater during glacial advance and up-flow during glacial retreat are greatest if the loading efficiency of the shield rock is low. The maximum rate of ground-water discharge occurs at the receding ice margin, and some discharge occurs below incursive post-glacial seas. The simulation results suggest that vertical movement of deep shield brines induced by the next few glacial cycles should not increase the concentration of dissolved solids significantly above present-day levels. However, the concentration of dissolved solids should decrease significantly at depths of up to several kilometers during periods of glacial meltwater recharge. The meltwater may reside in the subsurface for periods exceeding 10 ka and may bring oxygenated conditions to an otherwise reducing chemical environment.

Detecting Below-Ground Processes, Diversity, and Ecosystem Function in a Savanna Ecosystem Using Spectroscopy Across Different Vegetation Layers

NASA Astrophysics Data System (ADS)

Cavender-Bares, J.; Schweiger, A. K.; Madritch, M. D.; Gamon, J. A.; Hobbie, S. E.; Montgomery, R.; Townsend, P. A.

2017-12-01

Above-and below-ground plant traits are important for substrate input to the rhizosphere. The substrate composition of the rhizosphere, in turn, affects the diversity of soil organisms, influences soil biochemistry, and water content, and resource availability for plant growth. This has substantial consequences for ecosystem functions, such as above-ground productivity and stability. Above-ground plant chemical and structural traits can be linked to the characteristics of other plant organs, including roots. Airborne imaging spectroscopy has been successfully used to model and predict chemical and structural traits of the above-ground vegetation. However, remotely sensed images capture, almost exclusively, signals from the top of the canopy, providing limited direct information about understory vegetation. Here, we use a data set collected in a savanna ecosystem consisting of spectral measurements gathered at the leaf, the whole plant, and vegetation canopy level to test for hypothesized linkages between above- and below-ground processes that influence root biomass, soil biochemistry, and the diversity of the soil community. In this environment, consisting of herbaceous vegetation intermixed with shrubs and trees growing at variable densities, we investigate the contribution of different vegetation strata to soil characteristics and test the ability of imaging spectroscopy to detect these in plant communities with contrasting vertical structure.

Robonaut 2 - Preparing for Intra-Vehicular Mobility on the International Space Station

NASA Technical Reports Server (NTRS)

Badger, Julia; Diftler, Myron; Hulse, Aaron; Taylor, Ross

2013-01-01

Robonaut 2 (R2) has been undergoing experimental trials on board the International Space Station (ISS) for more than a year. This upper-body anthropomorphic robotic system shown in Figure 1 has been making steady progress after completing its initial checkout. R2 demonstrated free space motion, physically interacted with its human crew mates, manipulated interfaces on its task board and has even used its first tool. This steady growth in capability will lead R2 to its next watershed milestone. Developers are currently testing prototype robotic climbing appendages and a battery backpack in preparation of sending flight versions of both subsystems to the ISS in late 2013. Upon integration of its new components, R2 will be able to go mobile inside the space station with a twofold agenda. First, R2 will learn to maneuver in microgravity in the best possible laboratory for such a task. Second, it will start providing early payback to the ISS program by helping with intra-vehicular (IVA) maintenance tasks. The experience gained inside the ISS will be invaluable in reducing risk when R2 moves to its next stage and is deployed as an extra-vehicular (EVA) tool. Even on its current fixed base stanchion, R2 has already shown its capability of performing several maintenance tasks on the ISS. It has measured the air flow through one of the stations vents and provided previously unavailable real time flow data to ground operators. R2 has cleaned its first handrail, exciting some crew members that perhaps Saturday morning housekeeping on the station may someday become a task they can hand off to their robotic colleague. Other tasks, including using radio frequency identification (RFID) tools for inventory tasks or vacuuming air filters, have also been suggested and will be explored. Once mobile, R2 will take on these tasks and more to free up crew time for more important science and exploration pursuits. In addition to task exploration, research and testing is happening on orbit to prepare for R2 mobility operations. The current vision system in R2 s head is being used to identify and localize IVA handrails throughout the US Lab and ground control software is being updated and integrated in advance of supporting mobility operations.

Ground-water protection, low-level waste, and below regulatory concern: What`s the connection?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gruhlke, J.M.; Galpin, F.L.

1991-12-31

The Environmental Protection Agency (EPA) has a responsibility to protect ground water and drinking water under a wide variety of statutes. Each statute establishes different but specific requirements for EPA and applies to diverse environmental contaminants. Radionuclides are but one of the many contaminants subject to this regulatory matrix. Low-level radioactive waste (LLW) and below regulatory concern (BRC) are but two of many activities falling into this regulatory structure. The nation`s ground water serves as a major source of drinking water, supports sensitive ecosystems, and supplies the needs of agriculture and industry. Ground water can prove enormously expensive to cleanmore » up. EPA policy for protecting ground water has evolved considerably over the last ten years. The overall goal is to prevent adverse effects to human health, both now and in the future, and to protect the integrity of the nation`s ground-water resources. The Agency uses the Maximum Contaminant Levels (MCLs) under the Safe Drinking Water Act as reference points for protection in both prevention and remediation activities. What`s the connection? Both low-level waste management and disposal activities and the implementation of below regulatory concern related to low-level waste disposal have the potential for contaminating ground water. EPA is proposing to use the MCLs as reference points for low-level waste disposal and BRC disposal in order to define limits to the environmental contamination of ground water that is, or may be, used for drinking water.« less

The Lower Extremity Biomechanics of Single- and Double-Leg Stop-Jump Tasks

PubMed Central

2011-01-01

The anterior cruciate ligament (ACL) injury is a common occurrence in sports requiring stop-jump tasks. Single- and double-leg stop-jump techniques are frequently executed in sports. The higher risk of ACL injury in single-leg drop landing task compared to a double-leg drop landing task has been identified. However the injury bias between single- and double-leg landing techniques has not been investigated for stop-jump tasks. The purpose of this study was to determine the differences between single- and double-leg stop-jump tasks in knee kinetics that were influenced by the lower extremity kinematics during the landing phase. Ground reaction force, lower extremity kinematics, and knee kinetics data during the landing phase were obtained from 10 subjects performing single- and double-leg stop-jump tasks, using motion-capture system and force palates. Greater peak posterior and vertical ground reaction forces, and peak proximal tibia anterior and lateral shear forces (p < 0.05) during landing phase were observed of single-leg stop-jump. Single-leg stop-jump exhibited smaller hip and knee flexion angle, and knee flexion angular velocity at initial foot contact with the ground (p < 0.05). We found smaller peak hip and knee flexion angles (p < 0.05) during the landing phase of single-leg stop-jump. These results indicate that single-leg landing may have higher ACL injury risk than double-leg landing in stop-jump tasks that may be influenced by the lower extremity kinematics during the landing phase. Key points Non-contact ACL injuries are more likely to occur during the single-leg stop-jump task than during the double-leg stop-jump task. Single-leg stop-jump exhibited greater peak proximal tibia anterior and lateral shear forces, and peak posterior and vertical ground reaction forces during the landing phase than the double-leg stop-jump task. Single-leg stop-jump exhibited smaller hip flexion angle, knee flexion angle, and knee flexion angular velocity at initial foot contact with the ground. Single-leg stop-jump exhibited greater peak knee extension and valgus moment during the landing phase than the double-leg stop-jump task. Single-leg stop-jump extended the hip joint at initial foot contact with the ground. PMID:24149308

Electron Excitation Rate Coefficients for Transitions from the IS21S Ground State to the 1S2S1,3S and 1S2P1,3P0 Excited States of Helium

NASA Astrophysics Data System (ADS)

Aggarwal, K. M.; Kingston, A. E.; McDowell, M. R. C.

1984-03-01

The available experimental and theoretical electron impact excitation cross section data for the transitions from the 1s2 1S ground state to the 1s2s 1,3S and 1s2p 1,3P0 excited states of helium are assessed. Based on this assessed data, excitation rate coefficients are calculated over a wide electron temperature range below 3.0×106K. A comparison with other published results suggests that the rates used should be lower by a factor of 2 or more.

Ultrafast internal conversion dynamics of highly excited pyrrole studied with VUV/UV pump probe spectroscopy.

PubMed

Horton, Spencer L; Liu, Yusong; Chakraborty, Pratip; Matsika, Spiridoula; Weinacht, Thomas

2017-02-14

We study the relaxation dynamics of pyrrole after excitation with an 8 eV pump pulse to a state just 0.2 eV below the ionization potential using vacuum ultraviolet/ultraviolet pump probe spectroscopy. Our measurements in conjunction with electronic structure calculations indicate that pyrrole undergoes rapid internal conversion to the ground state in less than 300 fs. We find that internal conversion to the ground state dominates over dissociation.

Cybersecurity of Critical Control Networks

DTIC Science & Technology

2015-07-14

project are included below. The tasks include work in link encryption for existing legacy SCADA equipment, where we continue to develop lightweight...language for authoring and monitoring compliance of SCADA systems, including technologies for a “policy monitor” which reports out on any observance issues...Acquisition ( SCADA ). Details of each project are included below. The tasks include work in link encryption for existing legacy SCADA equipment

Exponentially-Biased Ground-State Sampling of Quantum Annealing Machines with Transverse-Field Driving Hamiltonians

NASA Technical Reports Server (NTRS)

Mandra, Salvatore

2017-01-01

We study the performance of the D-Wave 2X quantum annealing machine on systems with well-controlled ground-state degeneracy. While obtaining the ground state of a spin-glass benchmark instance represents a difficult task, the gold standard for any optimization algorithm or machine is to sample all solutions that minimize the Hamiltonian with more or less equal probability. Our results show that while naive transverse-field quantum annealing on the D-Wave 2X device can find the ground-state energy of the problems, it is not well suited in identifying all degenerate ground-state configurations associated to a particular instance. Even worse, some states are exponentially suppressed, in agreement with previous studies on toy model problems [New J. Phys. 11, 073021 (2009)]. These results suggest that more complex driving Hamiltonians are needed in future quantum annealing machines to ensure a fair sampling of the ground-state manifold.

Forest production responses to irrigation and fertilization are not explained by shifts in allocation

Treesearch

David R. Coyle; Mark D. Coleman

2005-01-01

Production increases in intensively managed forests have been obtained by improving resource availability through water and nutrient amendments. Increased stem production has been attributed to shifts in growth from roots to shoot, and such shifts would have important implications for below ground carbon sequestration. We examined above and below ground growth and...

Examination of Below-Ground Structure and Soil Respiration Rates of Stable and Deteriorating Salt Marshes in Jamaica Bay (NY)

EPA Science Inventory

CAT scan imaging is currently being used to examine below-ground peat and root structure in cores collected from salt marshes of Jamaica Bay, part of the Gateway National Recreation Area (NY). CAT scans or Computer-Aided Tomography scans use X-ray equipment to produce multiple i...

Above- and below-ground effects of aspen clonal regeneration and succession to conifers

Treesearch

Wayne D. Shepperd; Dale L. Bartos; Stephen A. Mata

2001-01-01

Above- and below-ground characteristics were measured and compared for six sets of paired trembling aspen (Populus tremuloides Michx.) clones on the Fishlake National Forest in central Utah. Three self-regenerating clones were compared with three non-regenerating clones and three pure aspen stands were compared with three mixed aspen-conifer stands. Regenerating clones...

Potentiometric Surface of the Lower Patapsco Aquifer in Southern Maryland, September 2007

USGS Publications Warehouse

Curtin, Stephen E.; Andreasen, David C.; Staley, Andrew W.

2009-01-01

This report presents a map showing the potentiometric surface of the lower Patapsco aquifer in the Patapsco Formation of Early Cretaceous age in Southern Maryland during September 2007. The map is based on water-level measurements in 65 wells. The highest measured water level was 111 feet above sea level near the northwestern boundary and outcrop area of the aquifer in northern Prince George's County. From this area, the potentiometric surface declined towards well fields at Severndale and Arnold. The measured ground-water levels were 87 feet below sea level at Severndale, and 42 feet below sea level at Arnold. There was also a cone of depression covering a large area in Charles County that includes Waldorf, La Plata, Indian Head, and the Morgantown power plant. The ground-water levels measured were as low as 219 feet below sea level at Waldorf, 187 feet below sea level at La Plata, 106 feet below sea level at Indian Head, and 89 feet below sea level at the Morgantown power plant.

Evidence for a gapped spin-liquid ground state in a kagome Heisenberg antiferromagnet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, Mingxuan; Imai, Takahashi; Han, Tian -Heng

2015-11-06

Here, the kagome Heisenberg antiferromagnet is a leading candidate in the search for a spin system with a quantum spin-liquid ground state. The nature of its ground state remains a matter of active debate. We conducted oxygen-17 single-crystal nuclear magnetic resonance (NMR) measurements of the spin-1/2 kagome lattice in herbertsmithite [ZnCu 3(OH) 6Cl 2], which is known to exhibit a spinon continuum in the spin excitation spectrum. We demonstrated that the intrinsic local spin susceptibility χkagome, deduced from the oxygen-17 NMR frequency shift, asymptotes to zero below temperatures of 0.03J, where J ~ 200 kelvin is the copper-copper superexchange interaction.more » Combined with the magnetic field dependence of χ kagome that we observed at low temperatures, these results imply that the kagome Heisenberg antiferromagnet has a spin-liquid ground state with a finite gap.« less

Evidence for a low-temperature magnetic ground state in double-perovskite iridates with I r5 +(5 d4) ions

NASA Astrophysics Data System (ADS)

Terzic, J.; Zheng, H.; Ye, Feng; Zhao, H. D.; Schlottmann, P.; De Long, L. E.; Yuan, S. J.; Cao, G.

2017-08-01

We report an unusual magnetic ground state in single-crystal, double-perovskite B a2YIr O6 and Sr-doped B a2YIr O6 with I r5 +(5 d4) ions. Long-range magnetic order below 1.7 K is confirmed by dc magnetization, ac magnetic susceptibility, and heat-capacity measurements. The observed magnetic order is extraordinarily delicate and cannot be explained in terms of either a low-spin S =1 state, or a singlet Jeff=0 state imposed by the spin-orbit interactions (SOI). Alternatively, the magnetic ground state appears consistent with a SOI that competes with comparable Hund's rule coupling and inherently large electron hopping, which cannot stabilize the singlet Jeff=0 ground state. However, this picture is controversial, and conflicting magnetic behavior for these materials is reported in both experimental and theoretical studies, which highlights the intricate interplay of interactions that determine the ground state of materials with strong SOI.

Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands

PubMed Central

Scott, Rose M.; Baillargeon, Renée

2016-01-01

When tested with traditional false-belief tasks, which require answering a standard question about the likely behavior of an agent with a false belief, children perform below chance until age 4 y or later. When tested without such questions, however, children give evidence of false-belief understanding much earlier. Are traditional tasks difficult because they tap a more advanced form of false-belief understanding (fundamental-change view) or because they impose greater processing demands (processing-demands view)? Evidence that young children succeed at traditional false-belief tasks when processing demands are reduced would support the latter view. In prior research, reductions in inhibitory-control demands led to improvements in young children’s performance, but often only to chance (instead of below-chance) levels. Here we examined whether further reductions in processing demands might lead to success. We speculated that: (i) young children could respond randomly in a traditional low-inhibition task because their limited information-processing resources are overwhelmed by the total concurrent processing demands in the task; and (ii) these demands include those from the response-generation process activated by the standard question. This analysis suggested that 2.5-y-old toddlers might succeed at a traditional low-inhibition task if response-generation demands were also reduced via practice trials. As predicted, toddlers performed above chance following two response-generation practice trials; toddlers failed when these trials either were rendered less effective or were used in a high-inhibition task. These results support the processing-demands view: Even toddlers succeed at a traditional false-belief task when overall processing demands are reduced. PMID:27821728

Lifelong Transfer Learning for Heterogeneous Teams of Agents in Sequential Decision Processes

DTIC Science & Technology

2016-06-01

making (SDM) tasks in dynamic environments with simulated and physical robots . 15. SUBJECT TERMS Sequential decision making, lifelong learning, transfer...sequential decision-making (SDM) tasks in dynamic environments with both simple benchmark tasks and more complex aerial and ground robot tasks. Our work...and ground robots in the presence of disturbances: We applied our methods to the problem of learning controllers for robots with novel disturbances in

Skill components of task analysis

PubMed Central

Rogers, Wendy A.; Fisk, Arthur D.

2017-01-01

Some task analysis methods break down a task into a hierarchy of subgoals. Although an important tool of many fields of study, learning to create such a hierarchy (redescription) is not trivial. To further the understanding of what makes task analysis a skill, the present research examined novices’ problems with learning Hierarchical Task Analysis and captured practitioners’ performance. All participants received a task description and analyzed three cooking and three communication tasks by drawing on their knowledge of those tasks. Thirty six younger adults (18–28 years) in Study 1 analyzed one task before training and five afterwards. Training consisted of a general handout that all participants received and an additional handout that differed between three conditions: a list of steps, a flow-diagram, and concept map. In Study 2, eight experienced task analysts received the same task descriptions as in Study 1 and demonstrated their understanding of task analysis while thinking aloud. Novices’ initial task analysis scored low on all coding criteria. Performance improved on some criteria but was well below 100 % on others. Practitioners’ task analyses were 2–3 levels deep but also scored low on some criteria. A task analyst’s purpose of analysis may be the reason for higher specificity of analysis. This research furthers the understanding of Hierarchical Task Analysis and provides insights into the varying nature of task analyses as a function of experience. The derived skill components can inform training objectives. PMID:29075044

Multiband electronic transport in α-Yb 1₋xSr x AlB 4 [ x = 0, 0.19(3)] single crystals

DOE PAGES

Ryu, Hyejin; Abeykoon, Milinda; Bozin, Emil; ...

2016-08-19

Here we report on the evidence for the multiband electronic transport in α- YbAlB 4 and α-Yb 0.81(2)Sr 0.19(3)AlB 4. Multiband transport reveals itself below 10 K in both compounds via Hall effect measurements, whereas anisotropic magnetic ground state sets in below 3 K in α-Yb 0.81(2)Sr 0.19(3)AlB 4. Our results show that Sr 2+ substitution enhances conductivity, but does not change the quasiparticle mass of bands induced by heavy fermion hybridization.

Identification of ground targets from airborne platforms

NASA Astrophysics Data System (ADS)

Doe, Josh; Boettcher, Evelyn; Miller, Brian

2009-05-01

The US Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD) sensor performance models predict the ability of soldiers to perform a specified military discrimination task using an EO/IR sensor system. Increasingly EO/IR systems are being used on manned and un-manned aircraft for surveillance and target acquisition tasks. In response to this emerging requirement, the NVESD Modeling and Simulation division has been tasked to compare target identification performance between ground-to-ground and air-to-ground platforms for both IR and visible spectra for a set of wheeled utility vehicles. To measure performance, several forced choice experiments were designed and administered and the results analyzed. This paper describes these experiments and reports the results as well as the NVTherm model calibration factors derived for the infrared imagery.

Zigzag antiferromagnetic ground state with anisotropic correlation lengths in the quasi-two-dimensional honeycomb lattice compound N a2C o2Te O6

NASA Astrophysics Data System (ADS)

Bera, A. K.; Yusuf, S. M.; Kumar, Amit; Ritter, C.

2017-03-01

The crystal structure, magnetic ground state, and the temperature-dependent microscopic spin-spin correlations of the frustrated honeycomb lattice antiferromagnet N a2C o2Te O6 have been investigated by powder neutron diffraction. A long-range antiferromagnetic (AFM) ordering has been found below TN˜24.8 K . The magnetic ground state, determined to be zigzag antiferromagnetic and characterized by a propagation vector k =(1 /2 0 0 ) , occurs due to the competing exchange interactions up to third-nearest neighbors within the honeycomb lattice. The exceptional existence of a limited magnetic correlation length along the c axis (perpendicular to the honeycomb layers in the a b planes) has been found even at 1.8 K, well below the TN˜24.8 K . The observed limited correlation along the c axis is explained by the disorder distribution of the Na ions within the intermediate layers between honeycomb planes. The reduced ordered moments mCo (1 )=2.77 (3 ) μB/C o2 + and mCo (2 )=2.45 (2 ) μB/C o2 + at 1.8 K reflect the persistence of spin fluctuations in the ordered state. Above TN˜24.8 K , the presence of short-range magnetic correlations, manifested by broad diffuse magnetic peaks in the diffraction patterns, has been found. Reverse Monte Carlo analysis of the experimental diffuse magnetic scattering data reveals that the spin correlations are mainly confined within the two-dimensional honeycomb layers (a b plane) with a correlation length of ˜12 Å at 25 K. The nature of the spin arrangements is found to be similar in both the short-range and long-range ordered magnetic states. This implies that the short-range correlation grows with decreasing temperature and leads to the zigzag AFM ordering at T ≤TN . The present study provides a comprehensive picture of the magnetic correlations over the temperature range above and below the TN and their relation to the crystal structure. The role of intermediate soft Na layers on the magnetic coupling between honeycomb planes is discussed.

Vanguard 2C VTOL Airplane Tested in the Ames 40x80 Foot Wind Tunnel.

NASA Image and Video Library

1960-02-01

Vanguard 2C vertical take-off and landing (VTOL) airplane, wind tunnel test. Front view from below, model 14 1/2 feet high disk off. Nasa Ames engineer Ralph Maki in photo. Variable height struts and ground plane, low pressure ratio, fan in wing. 02/01/1960.

Assessment of potable water quality including organic, inorganic, and trace metal concentrations.

PubMed

Nahar, Mst Shamsun; Zhang, Jing

2012-02-01

The quality of drinking water (tap, ground, and spring) in Toyama Prefecture, Japan was assessed by studying quality indicators including major ions, total carbon, and trace metal levels. The physicochemical properties of the water tested were different depending on the water source. Major ion concentrations (Ca(2+), K(+), Si(4+), Mg(2+), Na(+), SO(4)(2-), HCO(3)(-), NO(3)(-), and Cl(-)) were determined by ion chromatography, and the results were used to generate Stiff diagrams in order to visually identify different water masses. Major ion concentrations were higher in ground water than in spring and tap water. The relationship between alkaline metals (Na(+) and K(+)), alkaline-earth metals (Ca(2+) and Mg(2+)), and HCO(3)(-) showed little difference between deep and shallow ground water. Toyama ground, spring, and tap water were all the same type of water mass, called Ca-HCO(3). The calculated total dissolved solid values were below 300 mg/L for all water sources and met World Health Organization (WHO) water quality guidelines. Trace levels of As, Cd, Cr, Co, Cu, Fe, Pb, Mn, Mo, Ni, V, Zn, Sr, and Hg were detected in ground, spring, and tap water sources using inductively coupled plasma atomic emission spectrometry, and their levels were below WHO and Japanese water quality standard limits. Volatile organic carbon compounds were quantified by headspace gas chromatography-mass spectrometry, and the measured concentrations met WHO and Japanese water quality guidelines. Total trihalomethanes (THMs) were the major contaminant detected in all natural drinking water sources, but the concentration was highest in tap water (37.27 ± 0.05 μg/L). Notably, THMs concentrations reached up to 1.1 ± 0.05 μg/L in deep ground water. The proposed model gives an accurate description of the organic, inorganic, and trace heavy metal indicators studied here and may be used in natural clean water quality management. © Springer Science+Business Media B.V. 2011

Characterization of the X~ 2A1, A~ 2B1, and X~ 2Π electronic states of the Ga2H molecule and the X~ 2A' and A~ 2A'' isomerization transition states connecting the three minima

NASA Astrophysics Data System (ADS)

Wang, Hongyan; Wang, Suyun; Yan, Ge; Yamaguchi, Yukio; Schaefer, Henry F.

2006-01-01

A wide range of highly correlated ab initio methods has been used to predict the geometrical parameters of the linear (X˜Π2) and H-bridged (X˜A12 and ÃB12) Ga2H isomers and two isomerization transition states (X˜A'2 and ÃA″2) connecting the three minima. Dipole moments and vibrational frequencies are also obtained. The global minimum X˜A12 ground state of the H-bridged GaHGa isomer is predicted to lie only 1.6 [1.9 with the zero-point vibrational energy (ZPVE) corrections] kcalmol-1 below the ÃB12 state. The X˜A12 state lies 5.4kcalmol-1 below the X˜Π2 ground state of the linear GaGaH isomer at the coupled-cluster with single, double, and perturbative triple excitations [CCSD(T)] level of theory with the augmented correlation-consistent polarized valence quadruple-zeta (aug-cc-pVQZ) basis set. The full triples coupled-cluster method is found to alter these CCSD(T) predictions by as much as 0.3kcalmol-1. The forward isomerization barriers from the linear ground state to the X˜A'2 and ÃA″2 transition states are determined to be 3.3 and 5.3kcalmol-1, respectively. The reverse isomerization barrier between the X˜A12 GaHGa structure and the X˜Π2 GaGaH structure is predicted to be 8.6 (8.2 with the ZPVE corrections) kcalmol-1 at the aug-cc-pVQZ CCSD(T) level of theory.

Pentanuclear Cyanide-Bridged Complexes with High Spin Ground States S=6 and 9: Characterization and Magnetic Properties

NASA Astrophysics Data System (ADS)

Marvilliers, Arnaud; Hortholary, Cédric; Rogez, Guillaume; Audière, Jean-Paul; Rivière, Eric; Cano Boquera, Joan; Paulsen, Carley; Villar, Vincent; Mallah, Talal

2001-07-01

Two pentanuclear complexes are obtained from the reaction of hexacyanochromate(III) with one to two molar equivalents of [Ni(H2O)6]2+ and bidentate organic ligands that chelate the metal ion, leaving two coordination sites in cis positions. Even though the crystal structure was not solved, the full characterization supports the formation of pentanuclear discrete species. [Cr(CN)6]2[Ni(HIM2-py)2]3·7H2O, 1, has a ground spin state S=6 owing to the ferromagnetic interaction between CrIII (S=3/2) and NII (S=1). The presence of six organic radicals that couple ferromagnetically with NiII in [Cr(CN)6]2[Ni(IM2-py)2]3·7H2O, 2, leads to an S=9 ground state. A.c. susceptibility measurements below 2K indicate the occurrence of an antiferromagnetic order at 1.5 K in 2.

Effects of nitrogen with and without acidified sulphur on an ectomycorrhizal community in a Sitka spruce (Picea sitchensis Bong. Carr) forest.

PubMed

Carfrae, J A; Skene, K R; Sheppard, L J; Ingleby, K; Crossley, A

2006-05-01

This preliminary study investigated the effects of enhanced nitrogen (NH4NO3 at 48 kg ha(-1) y(-1)), sulphur (Na2SO4 at 50 kg ha(-1) y(-1)), acidified nitrogen and sulphur (H2SO4 + NH4NO3) at pre-stated doses (pH 2.5), and acidified nitrogen and sulphur deposition at double these doses on the ectomycorrhizal community associated with a 13-year-old Sitka spruce (Picea sitchensis) forest. Sulphur deposition had little impact on below ground ectomycorrhizal diversity, but stimulated sporocarp production. Nitrogen inputs increased below ground colonisation compared to acidified nitrogen and sulphur, largely due to an increase in Tylospora fibrillosa colonisation. Sporocarp production and ectomycorrhizal root colonisation by Lactarius rufus were reduced in the nitrogen treated plots. These observations suggest that nitrogen deposition to a young plantation may suppress ectomycorrhizal fungi producing large sporocarps. It is proposed that enhanced nitrogen deposition increases ectomycorrhizal nitrogen assimilation, consuming more carbon and leaving less for extrametrical mycelium and sporocarp development.

Development of Principles for Multimodal Displays in Army Human-Robot Operations

DTIC Science & Technology

2010-06-01

Research Laboratory ATTN: RDRL- HRM -D Aberdeen Proving Ground, MD 21005-5425 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT...the practical limitations of various cognitive resource channels for HRI tasks. 2.1.2 Purpose Now that MRT and the common workload manipulations...with more mission targets. • Workload conditions were not counter-balanced for practice effects. 7 Increasing task difficulty generally

Trophic cascades, invasive species and body-size hierarchies interactively modulate climate change responses of ecotonal temperate-boreal forest.

PubMed

Frelich, Lee E; Peterson, Rolf O; Dovčiak, Martin; Reich, Peter B; Vucetich, John A; Eisenhauer, Nico

2012-11-05

As the climate warms, boreal tree species are expected to be gradually replaced by temperate species within the southern boreal forest. Warming will be accompanied by changes in above- and below-ground consumers: large moose (Alces alces) replaced by smaller deer (Odocoileus virginianus) above-ground, and small detritivores replaced by larger exotic earthworms below-ground. These shifts may induce a cascade of ecological impacts across trophic levels that could alter the boreal to temperate forest transition. Deer are more likely to browse saplings of temperate tree species, and European earthworms favour seedlings of boreal tree species more than temperate species, potentially hindering the ability of temperate tree species to expand northwards. We hypothesize that warming-induced changes in consumers will lead to novel plant communities by changing the filter on plant species success, and that above- and below-ground cascades of trophic interactions will allow boreal tree species to persist during early phases of warming, leading to an abrupt change at a later time. The synthesis of evidence suggests that consumers can modify the climate change-induced transition of ecosystems.

Chemical Library Screening for Potential Therapeutics Using Novel Cell Based Models of ALS

DTIC Science & Technology

2017-06-01

Major Task 1, Subtask 1. Our first major activity in year 1 was the design and engineering of a custom inducible plasmid for expressing fluorescently...back to that construct. Other achievements during this first major activity derived from investigating why Broccoli RNA aptamer did not fold...These are outlined below in the CHANGES/PROBLEMS section. Major Task 1, Subtask 2. Our second major activity in year 1 was to generate human neural

Effect of simulated commercial flight on oxygenation in patients with interstitial lung disease and chronic obstructive pulmonary disease

PubMed Central

Seccombe, L; Kelly, P; Wong, C; Rogers, P; Lim, S; Peters, M

2004-01-01

Background: Commercial aircraft cabins provide a hostile environment for patients with underlying respiratory disease. Although there are algorithms and guidelines for predicting in-flight hypoxaemia, these relate to chronic obstructive pulmonary disease (COPD) and data for interstitial lung disease (ILD) are lacking. The purpose of this study was to evaluate the effect of simulated cabin altitude on subjects with ILD at rest and during a limited walking task. Methods: Fifteen subjects with ILD and 10 subjects with COPD were recruited. All subjects had resting arterial oxygen pressure (PaO2) of >9.3 kPa. Subjects breathed a hypoxic gas mixture containing 15% oxygen with balance nitrogen for 20 minutes at rest followed by a 50 metre walking task. Pulse oximetry (SpO2) was monitored continuously with testing terminated if levels fell below 80%. Arterial blood gas tensions were taken on room air at rest and after the resting and exercise phases of breathing the gas mixture. Results: In both groups there was a statistically significant decrease in arterial oxygen saturation (SaO2) and PaO2 from room air to 15% oxygen at rest and from 15% oxygen at rest to the completion of the walking task. The ILD group differed significantly from the COPD group in resting 15% oxygen SaO2, PaO2, and room air pH. Means for both groups fell below recommended levels at both resting and when walking on 15% oxygen. Conclusion: Even in the presence of acceptable arterial blood gas tensions at sea level, subjects with both ILD and COPD fall below recommended levels of oxygenation when cabin altitude is simulated. This is exacerbated by minimal exercise. Resting sea level arterial blood gas tensions are similarly poor in both COPD and ILD for predicting the response to simulated cabin altitude. PMID:15516473

Aboveground sink strength in forests controls the allocation of carbon below ground and its [CO2]-induced enhancement

Treesearch

Sari Palmroth; Ram Oren; Heather R. McCarthy; Kurt H. Johnsen; Adrien C. Finzi; John R. Butnor; Michael G. Ryan; William H. Schlesinger

2006-01-01

The partitioning among carbon (C) pools of the extra C captured under elevated atmospheric CO2 concentration ([CO2]) determines the enhancement in C sequestration, yet no clear partitioning rules exist. Here, we used first principles and published data from four free-air CO2 enrichment (FACE)...

The effect of ankle bracing on knee kinetics and kinematics during volleyball-specific tasks.

PubMed

West, T; Ng, L; Campbell, A

2014-12-01

The purpose of this study was to examine the effects of ankle bracing on knee kinetics and kinematics during volleyball tasks. Fifteen healthy, elite, female volleyball players performed a series of straight-line and lateral volleyball tasks with no brace and when wearing an ankle brace. A 14-camera Vicon motion analysis system and AMTI force plate were used to capture the kinetic and kinematic data. Knee range of motion, peak knee anterior-posterior and medial-lateral shear forces, and peak ground reaction forces that occurred between initial contact with the force plate and toe off were compared using paired sample t-tests between the braced and non-braced conditions (P < 0.05). The results revealed no significant effect of bracing on knee kinematics or ground reaction forces during any task or on knee kinetics during the straight-line movement volleyball tasks. However, ankle bracing was demonstrated to reduce knee lateral shear forces during all of the lateral movement volleyball tasks. Wearing the Active Ankle T2 brace will not impact knee joint range of motion and may in fact reduce shear loading to the knee joint in volleyball players. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The influence of heel height on vertical ground reaction force during landing tasks in recreationally active and athletic collegiate females.

PubMed

Lindenberg, Kelly M; Carcia, Christopher R

2013-02-01

To determine if heel height alters vertical ground reaction forces (vGRF) when landing from a forward hop or drop landing. Increased vGRF during landing are theorized to increase ACL injury risk in female athletes. Fifty collegiate females performed two single-limb landing tasks while wearing heel lifts of three different sizes (0, 12 & 24 mm) attached to the bottom of a athletic shoe. Using a force plate, peak vGRF at landing was examined. Repeated measures ANOVAs were used to determine the influence of heel height on the dependent measures. Forward hop task- Peak vGRF (normalized for body mass) with 0 mm, 12 mm, and 24 mm lifts were 2.613±0.498, 2.616±0.497 and 2.495±0.518% BW, respectively. Significant differences were noted between 0 and 24 mm lift (p<.001) and 12 and 24 mm lifts (p=.004), but not between the 0 and 12 mm conditions (p=.927). Jump-landing task- No significant differences were found in peak vGRF (p=.192) between any of the heel lift conditions. The addition of a 24 mm heel lift to the bottom of a sneaker significantly alters peak vGRF upon landing from a unilateral forward hop but not from a jumping maneuver.

An efficient approach to imaging underground hydraulic networks

NASA Astrophysics Data System (ADS)

Kumar, Mohi

2012-07-01

To better locate natural resources, treat pollution, and monitor underground networks associated with geothermal plants, nuclear waste repositories, and carbon dioxide sequestration sites, scientists need to be able to accurately characterize and image fluid seepage pathways below ground. With these images, scientists can gain knowledge of soil moisture content, the porosity of geologic formations, concentrations and locations of dissolved pollutants, and the locations of oil fields or buried liquid contaminants. Creating images of the unknown hydraulic environments underfoot is a difficult task that has typically relied on broad extrapolations from characteristics and tests of rock units penetrated by sparsely positioned boreholes. Such methods, however, cannot identify small-scale features and are very expensive to reproduce over a broad area. Further, the techniques through which information is extrapolated rely on clunky and mathematically complex statistical approaches requiring large amounts of computational power.

Evaluation of geohydrologic framework, recharge estimates and ground-water flow of the Joshua Tree area, San Bernardino County, California

USGS Publications Warehouse

Nishikawa, Tracy; Izbicki, John A.; Hevesi, Joseph A.; Stamos, Christina L.; Martin, Peter

2005-01-01

Ground water historically has been the sole source of water supply for the community of Joshua Tree in the Joshua Tree ground-water subbasin of the Morongo ground-water basin in the southern Mojave Desert. The Joshua Basin Water District (JBWD) supplies water to the community from the underlying Joshua Tree ground-water subbasin. The JBWD is concerned with the long-term sustainability of the underlying aquifer. To help meet future demands, the JBWD plans to construct production wells in the adjacent Copper Mountain ground-water subbasin. As growth continues in the desert, there may be a need to import water to supplement the available ground-water resources. In order to manage the ground-water resources and to identify future mitigating measures, a thorough understanding of the ground-water system is needed. The purpose of this study was threefold: (1) improve the understanding of the geohydrologic framework of the Joshua Tree and Copper Mountain ground-water subbasins, (2) determine the distribution and quantity of recharge using field and numerical techniques, and (3) develop a ground-water flow model that can be used to help manage the water resources of the region. The geohydrologic framework was refined by collecting and interpreting water-level and water-quality data, geologic and electric logs, and gravity data. The water-bearing deposits in the Joshua Tree and Copper Mountain ground-water subbasins are Quarternary alluvial deposits and Tertiary sedimentary and volcanic deposits. The Quarternary alluvial deposits were divided into two aquifers (referred to as the 'upper' and the 'middle' alluvial aquifers), which are about 600 feet (ft) thick, and the Tertiary sedimentary and volcanic deposits were assigned to a single aquifer (referred to as the 'lower' aquifer), which is as thick as 1,500 ft. The ground-water quality of the Joshua Tree and Copper Mountain ground-water subbasins was defined by collecting 53 ground-water samples from 15 wells (10 in the Joshua Tree ground-water subbasin and 5 in the Copper Mountain ground-water subbasin) between 1980 and 2002 and analyzing the samples for major ions, nutrients, and selected trace elements. Selected samples also were analyzed for oxygen-18, deuterium, tritium, and carbon-14. The water-quality data indicated that dissolved solids and nitrate concentrations were below regulatory limits for potable water; however, fluoride concentrations in the lower aquifer exceeded regulatory limits. Arsenic concentrations and chromium concentrations were generally below regulatory limits; however, arsenic concentrations measured in water from wells perforated in the lower aquifer exceeded regulatory limits. The carbon-14 activities ranged from 2 to 72 percent modern carbon and are consistent with uncorrected ground-water ages (time since recharge) of about 32,300 to 2,700 years before present. The oxygen-18 and deuterium composition of water sampled from the upper aquifer is similar to the volume-weighted composition of present-day winter precipitation indicating that winter precipitation was the predominant source of ground-water recharge. Field studies, conducted during water years 2001 through 2003 to determine the distribution and quantity of recharge, included installation of instrumented boreholes in selected washes and at a nearby control site. Core material and cuttings from the boreholes were analyzed for physical, chemical, and hydraulic properties. Instruments installed in the boreholes were monitored to measure changes in matric potential and temperature. Borehole data were supplemented with temperature data collected from access tubes installed at additional sites along study washes. Streambed hydraulic properties and the response of instruments to infiltration were measured using infiltrometers. Physical and geochemical data collected away from the stream channels show that direct infiltration of precipitation to depths below the root zone and subsequent gro

Ground-Water Quality Data in the San Fernando-San Gabriel Study Unit, 2005 - Results from the California GAMA Program

USGS Publications Warehouse

Land, Michael; Belitz, Kenneth

2008-01-01

Ground-water quality in the approximately 460 square mile San Fernando-San Gabriel study unit (SFSG) was investigated between May and July 2005 as part of the Priority Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Assessment Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The San Fernando-San Gabriel study was designed to provide a spatially unbiased assessment of raw ground-water quality within SFSG, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 52 wells in Los Angeles County. Thirty-five of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and seventeen wells were selected to aid in the evaluation of specific water-quality issues or changes in water chemistry along a historic ground-water flow path (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), 1,2,3-trichloropropane (1,2,3-TCP), and 1,4-dioxane], naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, and carbon-14, and stable isotopes of hydrogen, oxygen, and carbon), and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, samples for matrix spikes) were collected at approximately one-fifth (11 of 52) of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control results showed that the data had very little bias or variability and resulted in censoring of less than 0.7 percent (32 of 4,484 measurements) of the data collected for ground-water samples. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. VOCs were detected in more than 90 percent (33 of 35) of grid wells. For all wells sampled for SFSG, nearly all VOC detections were below health-based thresholds, and most were less than one-tenth of the threshold values. Samples from seven wells had at least one detection of PCE, TCE, tetrachloromethane, NDMA, or 1,2,3-TCP at or above a health-based threshold. Pesticides were detected in about 90 percent (31 of 35) grid wells and all detections in samples from SFSG wells were below health-based thresholds. Major ions, trace elements, and nutrients in samples from 17 SFSG wells were all below health-based thresholds, with the exception of one detection of nitrate that was above the USEPA maximum contaminant level (MCL-US). With the exception of 14 samples having radon-222 above the proposed MCL-US, radioactive constituents were below health-based thresholds for 16 of the SFSG wells sampled. Total dissolved solids in 6 of the 24 SFSG wells that were sampled ha

Ground-Water Quality Data in the Owens and Indian Wells Valleys Study Unit, 2006: Results from the California GAMA Program

USGS Publications Warehouse

Densmore, Jill N.; Fram, Miranda S.; Belitz, Kenneth

2009-01-01

Ground-water quality in the approximately 1,630 square-mile Owens and Indian Wells Valleys study unit (OWENS) was investigated in September-December 2006 as part of the Priority Basin Project of Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in collaboration with the California State Water Resources Control Board (SWRCB). The Owens and Indian Wells Valleys study was designed to provide a spatially unbiased assessment of raw ground-water quality within OWENS study unit, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 74 wells in Inyo, Kern, Mono, and San Bernardino Counties. Fifty-three of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and 21 wells were selected to evaluate changes in water chemistry in areas of interest (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater- indicator compounds], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), and 1,2,3- trichloropropane (1,2,3-TCP)], naturally occurring inorganic constituents [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water], and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. This study evaluated the quality of raw ground water in the aquifer in the OWENS study unit and did not attempt to evaluate the quality of treated water delivered to consumers. Water supplied to consumers typically is treated after withdrawal from the ground, disinfected, and blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with regulatory and non-regulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and non-regulatory thresholds established for aesthetic concerns (secondary maximum contamination levels, SMCL-CA) by CDPH. VOCs and pesticides were detected in samples from less than one-third of the grid wells; all detections were below health-based thresholds, and most were less than one-one hundredth of threshold values. All detections of perchlorate and nutrients in samples from OWENS were below health-based thresholds. Most detections of trace elements in ground-water samples from OWENS wells were below health-based thresholds. In samples from the 53 grid wells, three constituents were detected at concentrations above USEPA maximum contaminant levels: arsenic in 5 samples, uranium in 4 samples, and fluoride in 1 sample. Two constituents were detected at concentrations above CDPH notification levels (boron in 9 samples and vanadium in 1 sample), and two were above USEPA lifetime health advisory levels (molybdenum in 3 samples and strontium in 1 sample). Most of the samples from OWENS wells had concentrations of major elements, TDS, and trace elements below the non-enforceable standards set for aesthetic concerns. Samples from nine grid wells had concentrations of manganese, iron, or TDS above the SMCL-CAs.

A below-ground herbivore shapes root defensive chemistry in natural plant populations

PubMed Central

Huber, Meret; Bont, Zoe; Fricke, Julia; Brillatz, Théo; Aziz, Zohra; Gershenzon, Jonathan; Erb, Matthias

2016-01-01

Plants display extensive intraspecific variation in secondary metabolites. However, the selective forces shaping this diversity remain often unknown, especially below ground. Using Taraxacum officinale and its major native insect root herbivore Melolontha melolontha, we tested whether below-ground herbivores drive intraspecific variation in root secondary metabolites. We found that high M. melolontha infestation levels over recent decades are associated with high concentrations of major root latex secondary metabolites across 21 central European T. officinale field populations. By cultivating offspring of these populations, we show that both heritable variation and phenotypic plasticity contribute to the observed differences. Furthermore, we demonstrate that the production of the sesquiterpene lactone taraxinic acid β-d-glucopyranosyl ester (TA-G) is costly in the absence, but beneficial in the presence of M. melolontha, resulting in divergent selection of TA-G. Our results highlight the role of soil-dwelling insects for the evolution of plant defences in nature. PMID:27009228

Local figure-ground cues are valid for natural images.

PubMed

Fowlkes, Charless C; Martin, David R; Malik, Jitendra

2007-06-08

Figure-ground organization refers to the visual perception that a contour separating two regions belongs to one of the regions. Recent studies have found neural correlates of figure-ground assignment in V2 as early as 10-25 ms after response onset, providing strong support for the role of local bottom-up processing. How much information about figure-ground assignment is available from locally computed cues? Using a large collection of natural images, in which neighboring regions were assigned a figure-ground relation by human observers, we quantified the extent to which figural regions locally tend to be smaller, more convex, and lie below ground regions. Our results suggest that these Gestalt cues are ecologically valid, and we quantify their relative power. We have also developed a simple bottom-up computational model of figure-ground assignment that takes image contours as input. Using parameters fit to natural image statistics, the model is capable of matching human-level performance when scene context limited.

Comparison of in-flight and ground-based simulator derived flying qualities and pilot performance for approach and landing tasks

NASA Technical Reports Server (NTRS)

Grantham, William D.; Williams, Robert H.

1987-01-01

For the case of an approach-and-landing piloting task emphasizing response to the landing flare, pilot opinion and performance parameters derived from jet transport aircraft six-degree-of-freedom ground-based and in-flight simulators were compared in order to derive data for the flight-controls/flying-qualities engineers. The data thus obtained indicate that ground simulation results tend to be conservative, and that the effect of control sensitivity is more pronounced for ground simulation. The pilot also has a greater tendency to generate pilot-induced oscillation in ground-based simulation than in flight.

Shuttle mission simulator requirements report, volume 1, revision C

NASA Technical Reports Server (NTRS)

Burke, J. F.

1973-01-01

The contractor tasks required to produce a shuttle mission simulator for training crew members and ground personnel are discussed. The tasks will consist of the design, development, production, installation, checkout, and field support of a simulator with two separate crew stations. The tasks include the following: (1) review of spacecraft changes and incorporation of appropriate changes in simulator hardware and software design, and (2) the generation of documentation of design, configuration management, and training used by maintenance and instructor personnel after acceptance for each of the crew stations.

Summary of synfuel characterization and combustion studies

NASA Technical Reports Server (NTRS)

Schultz, D. F.

1983-01-01

Combustion component research studies aimed at evolving environmentally acceptable approaches for burning coal derived fuels for ground power applications were performed at the NASA Lewis Research Center under a program titled the ""Critical Research and Support Technology Program'' (CRT). The work was funded by the Department of Energy and was performed in four tasks. This report summarizes these tasks which have all been previously reported. In addition some previously unreported data from Task 4 is also presented. The first, Task 1 consisted of a literature survey aimed at determining the properties of synthetic fuels. This was followed by a computer modeling effort, Task 2, to predict the exhaust emissions resulting from burning coal liquids by various combustion techniques such as lean and rich-lean combustion. The computer predictions were then compared to the results of a flame tube rig, Task 3, in which the fuel properties were varied to simulate coal liquids. Two actual SRC 2 coal liquids were tested in this flame tube task.

NASA: Model development for human factors interfacing

NASA Technical Reports Server (NTRS)

Smith, L. L.

1984-01-01

The results of an intensive literature review in the general topics of human error analysis, stress and job performance, and accident and safety analysis revealed no usable techniques or approaches for analyzing human error in ground or space operations tasks. A task review model is described and proposed to be developed in order to reduce the degree of labor intensiveness in ground and space operations tasks. An extensive number of annotated references are provided.

The Effect of Predicted Vehicle Displacement on Ground Crew Task Performance and Hardware Design

NASA Technical Reports Server (NTRS)

Atencio, Laura Ashley; Reynolds, David W.

2011-01-01

NASA continues to explore new launch vehicle concepts that will carry astronauts to low- Earth orbit to replace the soon-to-be retired Space Transportation System (STS) shuttle. A tall vertically stacked launch vehicle (> or =300 ft) is exposed to the natural environment while positioned on the launch pad. Varying directional winds and vortex shedding cause the vehicle to sway in an oscillating motion. Ground crews working high on the tower and inside the vehicle during launch preparations will be subjected to this motion while conducting critical closeout tasks such as mating fluid and electrical connectors and carrying heavy objects. NASA has not experienced performing these tasks in such environments since the Saturn V, which was serviced from a movable (but rigid) service structure; commercial launchers are likewise attended by a service structure that moves away from the vehicle for launch. There is concern that vehicle displacement may hinder ground crew operations, impact the ground system designs, and ultimately affect launch availability. The vehicle sway assessment objective is to replicate predicted frequencies and displacements of these tall vehicles, examine typical ground crew tasks, and provide insight into potential vehicle design considerations and ground crew performance guidelines. This paper outlines the methodology, configurations, and motion testing performed while conducting the vehicle displacement assessment that will be used as a Technical Memorandum for future vertically stacked vehicle designs.

Geohydrology of deep-aquifer system monitoring-well site at Marina, Monterey County, California

USGS Publications Warehouse

Hanson, Randall T.; Everett, Rhett; Newhouse, Mark W.; Crawford, Steven M.; Pimentel, M. Isabel; Smith, Gregory A.

2002-01-01

In 2000, a deep-aquifer system monitoring-well site (DMW1) was completed at Marina, California to provide basic geologic and hydrologic information about the deep-aquifer system in the coastal region of the Salinas Valley. The monitoring-well site contains four wells in a single borehole; one completed from 930 to 950 feet below land surface (bls) in the Paso Robles Formation (DMW1-4); one 1,040 to 1,060 feet below land surface in the upper Purisima Formation (DMW1-3); one from 1,410 to 1,430 feet below land surface in the middle Purisima Formation (DMW1-2); and one from 1,820 to 1,860 feet below land surface in the lower Purisima Formation (DMW1-1). The monitoring site is installed between the coast and several deep-aquifer system supply wells in the Marina Coast Water District, and the completion depths are within the zones screened in those supply wells. Sediments below a depth of 955 feet at DMW1 are Pliocene age, whereas the sediments encountered at the water-supply wells are Pleistocene age at an equivalent depth. Water levels are below sea level in DMW1 and the Marina Water District deep-aquifer system supply wells, which indicate that the potential for seawater intrusion exists in the deep-aquifer system. If the aquifers at DMW1 are hydraulically connected with the submarine outcrops in Monterey Bay, then the water levels at the DMW1 site are 8 to 27 feet below the level necessary to prevent seawater intrusion. Numerous thick fine-grained interbeds and confining units in the aquifer systems retard the vertical movement of fresh and saline ground water between aquifers and restrict the movement of seawater to narrow water-bearing zones in the upper-aquifer system.Hydraulic testing of the DMW1 and the Marina Water District supply wells indicates that the tested zones within the deep-aquifer system are transmissive water-bearing units with hydraulic conductivities ranging from 2 to 14.5 feet per day. The hydraulic properties of the supply wells and monitoring wells are similar, even though the wells are completed in different geologic formations.Geophysical logs collected at the DMW1 site indicate saline water in most water-bearing zones shallower than 720 feet below land surface and from about 1,025 to 1,130 feet below land surface, and indicate fresher water from about 910 to 950 feet below land surface (DMW1-4), 1,130 to 1,550 feet below land surface, and below 1,650 feet below land surface. Temporal differences between electromagnetic induction logs indicate possible seasonal seawater intrusion in five water-bearing zones from 350 to 675 feet below land surface in the upper-aquifer system.The water-chemistry analyses from the deep-aquifer system monitoring and supply wells indicate that these deep aquifers in the Marina area contain potable water with the exception of the saline water in well DMW1-3. The saline water from well DMW1-3 has a chloride concentration of 10,800 milligrams per liter and dissolved solids concentration of 23,800 milligrams per liter. The source of this water was determined not to be recent seawater based on geochemical indicators and the age of the ground water. The high salinity of this ground water may be related to the dissolution of salts from the saline marine clays that surround the water-bearing zone screened by DMW1-3. The major ion water chemistry of the monitoring wells and the nearby MCWD water-supply wells are similar, which may indicate they are in hydraulic connection, even though the stratigraphic layers differ below 955 feet below land surface.No tritium was detected in samples from the deep monitoring wells. The lack of tritium suggest that there is no recent recharge water (less than 50 years old) in the deep-aquifer system at the DMW1 site. The carbon-14 analyses of these samples indicate ground water from the monitoring site was recharged thousands of years ago.

Data for developing allometric models and evaluating carbon stocks of the Zambezi Teak Forests in Zambia.

PubMed

Ngoma, Justine; Moors, Eddy; Kruijt, Bart; Speer, James H; Vinya, Royd; Chidumayo, Emmanuel N; Leemans, Rik

2018-04-01

This paper presents data on carbon stocks of tropical tree species along a rainfall gradient. The data was generated from the Sesheke, Namwala, and Kabompo sites in Zambia. Though above-ground data was generated for all these three sites, we uprooted trees to determine below-ground biomass from the Sesheke site only. The vegetation was assessed in all three sites. The data includes tree diameter at breast height (DBH), total tree height, wood density, wood dry weight and root dry weight for large (≥ 5 cm DBH) and small (< 5 cm DBH) trees. We further presented Root-to-Shoot Ratios of uprooted trees. Data on the importance-value indices of various species for large and small trees are also determined. Below and above-ground carbon stocks of the surveyed tree species are presented per site. This data were used by Ngoma et al. (2018) [1] to develop above and below-ground biomass models and the reader is referred to this study for additional information, interpretation, and reflection on applying this data.

Quenched crystal-field disorder and magnetic liquid ground states in Tb 2 Sn 2 - x Ti x O 7 [Crystal field disorder in the quantum spin ice ground state of Tb2Sn2-xTixO7

DOE PAGES

Gaulin, B. D.; Kermarrec, E.; Dahlberg, M. L.; ...

2015-06-01

Solid-solutions of the "soft" quantum spin ice pyrochlore magnets Tb 2B 2O 7 with B=Ti and Sn display a novel magnetic ground state in the presence of strong B-site disorder, characterized by a low susceptibility and strong spin fluctuations to temperatures below 0.1 K. These materials have been studied using ac-susceptibility and muSR techniques to very low temperatures, and time-of-flight inelastic neutron scattering techniques to 1.5 K. Remarkably, neutron spectroscopy of the Tb 3+ crystal field levels appropriate to at high B-site mixing (0.5 < x < 1.5 in Tb 2Sn 2-xTi xO 7) reveal that the doublet ground andmore » first excited states present as continua in energy, while transitions to singlet excited states at higher energies simply interpolate between those of the end members of the solid solution. The resulting ground state suggests an extreme version of a random-anisotropy magnet, with many local moments and anisotropies, depending on the precise local configuration of the six B sites neighboring each magnetic Tb 3+ ion.« less

Ground-Water Quality Data in the Central Eastside San Joaquin Basin 2006: Results from the California GAMA Program

USGS Publications Warehouse

Landon, Matthew K.; Belitz, Kenneth

2008-01-01

Ground-water quality in the approximately 1,695-square-mile Central Eastside study unit (CESJO) was investigated from March through June 2006 as part of the Statewide Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The study was designed to provide a spatially unbiased assessment of raw ground-water quality within CESJO, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 78 wells in Merced and Stanislaus Counties. Fifty-eight of the 78 wells were selected using a randomized grid-based method to provide statistical representation of the study unit (grid wells). Twenty of the wells were selected to evaluate changes in water chemistry along selected lateral or vertical ground-water flow paths in the aquifer (flow-path wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), gasoline oxygenates and their degradates, pesticides and pesticide degradates], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), and 1,2,3-trichloropropane (1,2,3-TCP)], inorganic constituents that can occur naturally [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, carbon-14, and uranium isotopes and stable isotopes of hydrogen, oxygen, nitrogen, sulfur, and carbon], and dissolved noble and other gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, samples for matrix spikes) were collected for approximately one-sixth of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control results showed that the environmental data were of good quality, with low bias and low variability, and resulted in censoring of less than 0.3 percent of the detections found in ground-water samples. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CADPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CADPH. VOCs and pesticides were detected in approximately half of the grid wells, and all detections in samples from CESJO wells were below health-based thresholds. All detections of nutrients and major elements in grid wells also were below health-based thresholds. Most detections of constituents of special interest, trace elements, and radioactive constituents in samples from grid wells were below health-based thresholds. Exceptions included two detections of arsenic that were above the USEPA maximum contaminant level (MCL-US), one detection of lead above the USEPA action level (AL-US), and one detection of vanadium and three detections of 1,2,3-TCP that were above the CADPH notification levels (NL-CA). All detections of radioactive constituents were below health-based thresholds, although fourteen samples had activities of radon-222 above the lower proposed MCL-US. Most of th

NH and OH Concentration Profiles in a Stoichiometric CH4/N2O Flame by Laser Excited Fluorescence and Absorption Techniques.

DTIC Science & Technology

1982-10-01

PROGRAM ELEMENT. PROJECT. TASK US Army Ballistic Research Laboratory ATTN: DRDAR-BLI 1L161102AH43 Aberdeen Proving Ground , MD 21005 It. CONTROLLING...34112 ABERDEEN PROVING GROUND Dir, USANSAA ATTN: DRXSY-D DRXSY-NP, H. Cohen Cdr, USATECOG ATTN: DRSTE-TO-F Dir, USACSL, Bldg E3516 ATTN: DRDAR-CLB-PA . U...Research Laboratory 1 1NECESSARYAberden IIF MAILED Aberdeen Proving Ground , MD 21005 [ IN THE _UNITED STATES OFFICIAL BUSINESS AOR PRIVAT U9. 0.3M

Potential for Non-Contact ACL Injury Between Step-Close-Jump and Hop-Jump Tasks.

PubMed

Wang, Li-I; Gu, Chin-Yi; Chen, Wei-Ling; Chang, Mu-San

2010-01-01

This study aimed to compare the kinematics and kinetics during the landing of hop-jump and step-close-jump movements in order to provide further inferring that the potential risk of ACL injuries. Eleven elite male volleyball players were recruited to perform hop-jump and step-close-jump tasks. Lower extremity kinematics and ground reaction forces during landing in stop-jump tasks were recorded. Lower extremity kinetics was calculated by using an inverse dynamic process. Step-close-jump tasks demonstrated smaller peak proximal tibia anterior shear forces during the landing phase. In step-close-jump tasks, increasing hip joint angular velocity during initial foot-ground contact decreased peak posterior ground reaction force during the landing phase, which theoretically could reduce the risk of ACL injury. Key pointsThe different landing techniques required for these two stop-jump tasks do not necessarily affect the jump height.Hop-jump decreased the hip joint angular velocity at initial foot contact with ground, which could lead to an increasing peak posterior GRF during the landing phase.Hop-jump decreased hip and knee joint angular flexion displacement during the landing, which could increase the peak vertical loading rate during the landing phase.

Fitness and Recreation Career Ladder AFSC 741X1.

DTIC Science & Technology

1987-12-01

all first-termers who monitor equipment and weightlifters . Gymnasium Attendants are performing very few tasks (average of 27 tasks). Most of their...has a TD of 4.84 (below the average of 5). But this task, if not accomplished properly, could lead to injury . Therefore, TE was high on this task. A

Spin ordering and electronic texture in the bilayer iridate Sr3Ir2O7

NASA Astrophysics Data System (ADS)

Dhital, Chetan; Khadka, Sovit; Yamani, Z.; de la Cruz, Clarina; Hogan, T. C.; Disseler, S. M.; Pokharel, Mani; Lukas, K. C.; Tian, Wei; Opeil, C. P.; Wang, Ziqiang; Wilson, Stephen D.

2012-09-01

Through a neutron scattering, charge transport, and magnetization study, the correlated ground state in the bilayer iridium oxide Sr3Ir2O7 is explored. Our combined results resolve scattering consistent with a high temperature magnetic phase that persists above 600 K, reorients at the previously defined TAF=280 K, and coexists with an electronic ground state whose phase behavior suggests the formation of a fluctuating charge or orbital phase that freezes below T*≈70 K. Our study provides a window into the emergence of multiple electronic order parameters near the boundary of the metal to insulator phase transition of the 5d Jeff=1/2 Mott phase.

Changes in ground-water quality in the Canal Creek Aquifer between 1995 and 2000-2001, West Branch Canal Creek area, Aberdeen Proving Ground, Maryland

USGS Publications Warehouse

Phelan, Daniel J.; Fleck, William B.; Lorah, Michelle M.; Olsen, Lisa D.

2002-01-01

Since 1917, Aberdeen Proving Ground, Maryland has been the primary chemical-warfare research and development center for the U.S. Army. Ground-water contamination has been documented in the Canal Creek aquifer because of past disposal of chemical and ordnance manufacturing waste. Comprehensive sampling for volatile organic compounds in ground water by the U.S. Geological Survey in the West Branch Canal Creek area was done in June?October 1995 and June?August 2000. The purpose of this report is (1) to compare volatile organic compound concentrations and determine changes in the ground-water contaminant plumes along two cross sections between 1995 and 2000, and (2) to incorporate data from new piezometers sampled in spring 2001 into the plume descriptions. Along the southern cross section, total concentrations of volatile organic compounds in 1995 were determined to be highest in the landfill area east of the wetland (5,200 micrograms per liter), and concentrations were next highest deep in the aquifer near the center of the wetland (3,300 micrograms per liter at 35 feet below land surface). When new piezometers were sampled in 2001, higher carbon tetrachloride and chloroform concentrations (2,000 and 2,900 micrograms per liter) were detected deep in the aquifer 38 feet below land surface, west of the 1995 sampling. A deep area in the aquifer close to the eastern edge of the wetland and a shallow area just east of the creek channel showed declines in total volatile organic compound concentrations of more than 25 percent, whereas between those two areas, con-centrations generally showed an increase of greater than 25 percent between 1995 and 2000. Along the northern cross section, total concentrations of volatile organic compounds in ground water in both 1995 and 2000 were determined to be highest (greater than 2,000 micrograms per liter) in piezometers located on the east side of the section, farthest from the creek channel, and concentrations were progressively lower at piezometer locations closer to the creek channel. Total volatile organic compound concentrations increased more than 25 percent in some areas in the middle depths of the aquifer; however, it could not be determined if a defined plume was moving farther downgradient along ground-water flow paths toward the creek channel, or vertically downward because of density differences within the aquifer.

Engineering development of selective agglomeration: Task 5, Bench- scale process testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-09-01

Under the overall objectives of DOE Contract ``Engineering Development of Selective Agglomeration,`` there were a number of specific objectives in the Task 5 program. The prime objectives of Task 5 are highlighted below: (1) Maximize process performance in pyritic sulfur rejection and BTU recovery, (2) Produce a low ash product, (3) Compare the performance of the heavy agglomerant process based on diesel and the light agglomerant process using heptane, (4) Define optimum processing conditions for engineering design, (5) Provide first-level evaluation of product handleability, and (6) Explore and investigate process options/ideas which may enhance process performance and/or product handleability.

Engineering development of selective agglomeration: Task 5, Bench- scale process testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-09-01

Under the overall objectives of DOE Contract Engineering Development of Selective Agglomeration,'' there were a number of specific objectives in the Task 5 program. The prime objectives of Task 5 are highlighted below: (1) Maximize process performance in pyritic sulfur rejection and BTU recovery, (2) Produce a low ash product, (3) Compare the performance of the heavy agglomerant process based on diesel and the light agglomerant process using heptane, (4) Define optimum processing conditions for engineering design, (5) Provide first-level evaluation of product handleability, and (6) Explore and investigate process options/ideas which may enhance process performance and/or product handleability.

Effector identity and orthogonal stimulus-response compatibility in blindness to response-compatible stimuli.

PubMed

Nishimura, Akio; Yokosawa, Kazuhiko

2010-03-01

Perceiving a visual stimulus is hampered when the stimulus is compatible with simultaneously prepared or executed action (blindness effect). We explored the roles of the effector identity of the responding hand and of orthogonal compatibility (above-right/below-left correspondence) in the blindness effect. In Experiment 1, participants conducted bimanual key presses with vertically arranged responses while perceiving a brief presentation of rightward or leftward arrowheads. A blindness effect based on the effector identity did emerge, but only with the above-right/below-left key-hand arrangement. An orthogonal blindness effect was not found in Experiment 2 with a horizontal key-press action task and a vertical arrowhead perception task. We concluded that the anatomical identity of the responding hand was not integrated into the action plan with an orthogonally incompatible key-hand arrangement. The findings are discussed in terms of the generality and limits of the blindness effect, and hierarchical response coding.

Task 1: Correlation of satellite and ground data in air pollution studies. Task 2: Investigation to relate the chlorophyll and suspended sediment content in the waters of the lower Chesapeake Bay to ERTS-1 imagery. Task 3: The use of ERTS-1 to more fully utilize and apply marine station data to the study of productivity along the Eastern Shelf expanded waters of the United States

NASA Technical Reports Server (NTRS)

Copeland, G. E. (Principal Investigator); Bandy, A. R.; Fleischer, P.; Ludwick, J. C. (Principal Investigator); Hanna, W. J.; Gosink, T. A.; Bowker, D. W.; Marshall, H. G. (Principal Investigator)

1972-01-01

The author has identified the following significant results. Analysis of U-2 imagery of CARETS site indicates smoke plumes can be easily detected. First look at selected ERTS-1 color composites demonstrates plumes from forest fires can be detected.

Evaluation of subsurface exploration, sampling, and water-quality-analysis methods at an abandoned wood-preserving plant site at Jackson, Tennessee

USGS Publications Warehouse

Parks, W.S.; Carmichael, J.K.; Mirecki, J.E.

1993-01-01

Direct Push Technology (DPT) and a modified-auger method of sampling were used at an abandoned wood-preserving plant site at Jackson, Tennessee, to collect lithologic data and ground-water samples in an area known to be affected by a subsurface creosote plume. The groundwater samples were analyzed using (1) gas chromatography with photo-ionization detection (GS/PID), (2) high- performance liquid chromatography (HPLC), (3) colonmetric phenol analysis, and (4) toxicity bioassay. DPT piezocone and cone-penetrometer-type tools provided lithologic data and ground-water samples at two onsite stations to a depth of refusal of about 35 feet below land surface. With the assistance of an auger rig, this depth was extended to about 65 feet by pushing the tools in advance of the augers. Following the DPT work, a modified-auger method was tested by the USGS. This method left doubt as to the integrity of the samples collected once zones of contamination were penetrated. GC/PID and HPLC methods of water-quality analysis provided the most data concerning contaminants in the ground-water and proved to be the most effective in creosote plume detection. Analyses from these methods showed that the highest concentrations of contaminants were detected at depths less than about 35 feet below land surface. Phenol analyses provided data supplemental to the HPLC analyses. Bioassay data indicated that toxicity associated with the plume extended to depths of about 55 feet below land surface.

National facilities study. Volume 2: Task group on aeronautical research and development facilities report

NASA Technical Reports Server (NTRS)

1994-01-01

The Task Group on Aeronautics R&D Facilities examined the status and requirements for aeronautics facilities against the competitive need. Emphasis was placed on ground-based facilities for subsonic, supersonic and hypersonic aerodynamics, and propulsion. Subsonic and transonic wind tunnels were judged to be most critical and of highest priority. Results of the study are presented.

FeRh ground state and martensitic transformation

DOE PAGES

Zarkevich, Nikolai A.; Johnson, Duane D.

2018-01-09

Cubic B2 FeRh exhibits a metamagnetic transition [(111) antiferromagnet (AFM) to ferromagnet (FM)] around 353 K and remains structurally stable at higher temperatures. However, the calculated zero-Kelvin phonons of AFM FeRh exhibit imaginary modes at M points in the Brillouin zone, indicating a premartensitic instability, which is a precursor to a martensitic transformation at low temperatures. Combining electronic-structure calculations with ab initio molecular dynamics, conjugate gradient relaxation, and the solid-state nudged-elastic band methods, we predict that AFM B2 FeRh becomes unstable at ambient pressure and transforms without a barrier to an AFM(111) orthorhombic (martensitic) ground state below 90±10K. In conclusion,more » we also consider competing structures, in particular, a tetragonal AFM(100) phase that is not the global ground state, as proposed, but a constrained solution.« less

Influence of Atmospheric CO{sub 2} enrichment on rangeland forage quality and animal grazing. Final technical report, September 1, 1989--August 31, 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sionit, N.

1992-12-31

Increased biomass production in terrestrial ecosystems with elevated atmospheric CO{sub 2}, may be constrained by nutrient limitations as a result of increased requirement or reduced availability caused by reduced turnover rates of nutrients. To determine the short-term impact of nitrogen (N) fertilization on plant biomass production under elevated CO{sub 2}, we compared the response of N-fertilized tallgrass prairie at ambient and twice-ambient CO{sub 2} levels. Native tall grass prairie plots were exposed continuously to ambient and twice-ambient CO{sub 2}. We compared our results to an unfertilized companion experiment on the same research site. Above- and below-ground biomass production and leafmore » area of fertilized plots were greater with elevated than ambient CO{sub 2}. Nitrogen concentration was lower in plants exposed to elevated CO{sub 2}, but total standing crop N was greater at high CO{sub 2} increased root biomass under elevated CO{sub 2} apparently increased N uptake. The biomass production response to elevated CO{sub 2} was much greater on N-fertilized than unfertilized prairie, particularly in the dry year. We conclude that biomass production response to elevated C{sub 2} was suppressed by N limitation in years with below-normal precipitation. Reduced N concentration in above- and below-ground biomass could slow microbial degradation of soil organic matter and surface litter. The reduced tissue N concentration higher acid detergent fiber under elevated CO{sub 2} compared to ambient for forage indicated that ruminant growth and reproduction could be reduced under elevated CO{sub 2}.« less

Imaging spectroscopy links aspen genotype with below-ground processes at landscape scales

PubMed Central

Madritch, Michael D.; Kingdon, Clayton C.; Singh, Aditya; Mock, Karen E.; Lindroth, Richard L.; Townsend, Philip A.

2014-01-01

Fine-scale biodiversity is increasingly recognized as important to ecosystem-level processes. Remote sensing technologies have great potential to estimate both biodiversity and ecosystem function over large spatial scales. Here, we demonstrate the capacity of imaging spectroscopy to discriminate among genotypes of Populus tremuloides (trembling aspen), one of the most genetically diverse and widespread forest species in North America. We combine imaging spectroscopy (AVIRIS) data with genetic, phytochemical, microbial and biogeochemical data to determine how intraspecific plant genetic variation influences below-ground processes at landscape scales. We demonstrate that both canopy chemistry and below-ground processes vary over large spatial scales (continental) according to aspen genotype. Imaging spectrometer data distinguish aspen genotypes through variation in canopy spectral signature. In addition, foliar spectral variation correlates well with variation in canopy chemistry, especially condensed tannins. Variation in aspen canopy chemistry, in turn, is correlated with variation in below-ground processes. Variation in spectra also correlates well with variation in soil traits. These findings indicate that forest tree species can create spatial mosaics of ecosystem functioning across large spatial scales and that these patterns can be quantified via remote sensing techniques. Moreover, they demonstrate the utility of using optical properties as proxies for fine-scale measurements of biodiversity over large spatial scales. PMID:24733949

Hydrogeologic framework and water quality of the Vermont Army National Guard Ethan Allen Firing Range, northern Vermont, October 2002 through December 2003

USGS Publications Warehouse

Clark, Stewart F.; Chalmers, Ann; Mack, Thomas J.; Denner, Jon C.

2005-01-01

The Ethan Allen Firing Range of the Vermont Army National Guard is a weapons-testing and training facility in a mountainous region of Vermont that has been in operation for about 80 years. The hydrologic framework and water quality of the facility were assessed between October 2002 and December 2003. As part of the study, streamflow was continuously measured in the Lee River and 24 observation wells were installed at 19 locations in the stratified drift and bedrock aquifers to examine the hydrogeology. Chemical analyses of surface water, ground water, streambed sediment, and fish tissue were collected to assess major ions, trace elements, nutrients, and volatile and semivolatile compounds. Sampling included 5 surface-water sites sampled during moderate and low-flow conditions; streambed-sediment samples collected at the 5 surface-water sites; fish-tissue samples collected at 3 of the 5 surface-water sites; macroinvertebrates collected at 4 of the 5 surface-water sites; and ground-water samples collected from 10 observation wells, and samples collected at all surface- and ground-water sites. The hydrogeologic framework at the Ethan Allen Firing Range is dominated by the upland mountain and valley setting of the site. Bedrock wells yield low to moderate amounts of water (0 to 23 liters per minute). In the narrow river valleys, layered stratified-drift deposits of sand and gravel of up to 18 meters thick fill the Lee River and Mill Brook Valleys. In these deposits, the water table is generally within 3 meters below the land surface and overall ground-water flow is from east to west. Streamflow in the Lee River averaged 0.72 cubic meters per second (25.4 cubic feet per second) between December 2002 and December 2003. Streams are highly responsive to precipitation events in this mountainous environment and a comparison with other nearby watersheds shows that Lee River maintains relatively high streamflow during dry periods. Concentrations of trace elements and nutrients in surface-water samples are well below freshwater-quality guidelines for the protection of aquatic life. Brook-trout samples collected in 1992 and 2003 show trace-metal concentrations have decreased over the past 11 years. concentrations in water samples are well below levels that restrict swimming at all five stream sites at moderate and low-flow conditions and in all observation wells. Comparisons among surface-water, streambed-sediment, and biological samples collected in 2003 to earlier studies at the Ethan Allen Firing Range indicate water-quality conditions are similar or have improved over the past 15 years. Ground water in the stratified-drift aquifers at the facility is well buffered with relatively high alkalinities and pH greater than 6. Concentrations of arsenic, cadmium, chromium, lead, nickel, uranium, and zinc were below detection levels in ground-water samples. Barium, cobalt, copper, iron, manganese, molybdenum, and strontium were the only trace elements detected in ground-water samples. Cobalt and iron were detected at low levels in two wells near Mill Brook, and copper was detected at the detection limit in one of these wells. These same two wells had concentrations of barium and manganese 2 to 10 times greater than other ground-water samples. Concentrations of nutrients are at or below detection levels in most ground-water samples. Volatile organic compounds and semivolatile organic compounds were not detected in any water samples from the Ethan Allen Firing Range.

Ultrafast primary processes of an iron-(III) azido complex in solution induced with 266 nm light.

PubMed

Vennekate, Hendrik; Schwarzer, Dirk; Torres-Alacan, Joel; Krahe, Oliver; Filippou, Alexander C; Neese, Frank; Vöhringer, Peter

2012-05-14

The ultrafast photo-induced primary processes of the iron-(III) azido complex, [Fe(III)N(3)(cyclam-acetato)] PF(6) (1), in acetonitrile solution at room temperature were studied using femtosecond spectroscopy with ultraviolet (UV) excitation and mid-infrared (MIR) detection. Following the absorption of a 266 nm photon, the complex undergoes an internal conversion back to the electronic doublet ground state at a time scale below 2 ps. Subsequently, the electronic ground state vibrationally cools with a characteristic time constant of 13 ps. A homolytic bond cleavage was also observed by the appearance of ground state azide radicals, which were identified by their asymmetric stretching vibration at 1659 cm(-1). The azide radical recombines in a geminate fashion with the iron containing fragment within 20 ps. The cage escape leading to well separated fragments after homolytic Fe-N bond breakage was found to occur with a quantum yield of 35%. Finally, non-geminate recombination at nanosecond time scales was seen to further reduce the photolytic quantum yield to below 20% at a wavelength of 266 nm. This journal is © the Owner Societies 2012

Particle Concentration and Aggregation by Turbulence and TES Spectra Classification, Visualization and Analysis

NASA Technical Reports Server (NTRS)

Hogan, Robert

2004-01-01

This report is the final report for the Cooperative Agreement NCC2-1292. It is a compilation of publications produced under this Cooperative Agreement and conference presentations. The tasks outlined in the various proposals are listed below with a brief comment as to the research performed.

Revisiting the ground state of CoAl 2 O 4 : Comparison to the conventional antiferromagnet MnAl 2 O 4

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacDougall, Gregory J.; Aczel, Adam A.; Su, Yixi

The A-site spinel material CoAl 2O 4 is a physical realization of the frustrated diamond-lattice antiferromagnet, a model in which unique incommensurate or “spin-spiral-liquid” ground states are predicted. Our previous single-crystal neutron scattering study instead classified it as a “kinetically inhibited” antiferromagnet, where the long-ranged correlations of a collinear Néel ground state are blocked by the freezing of domain-wall motion below a first-order phase transition at T*=6.5 K. This study provides new data sets from a number of experiments, which support and expand this work in several important ways. We show that the phenomenology leading to the kinetically inhibited ordermore » is unaffected by sample measured and instrument resolution, while new low-temperature measurements reveal spin correlations are unchanging between T=2 K and 250 mK, consistent with a frozen state. Polarized diffuse neutron measurements show several interesting magnetic features, which can be entirely explained by the existence of short-ranged Néel order. Finally, and crucially, this paper presents some neutron scattering studies of single crystalline MnAl 2O 4, which acts as an unfrustrated analog to CoAl 2O 4 and shows all the hallmarks of a classical antiferromagnet with a continuous phase transition to Néel order at T N=39 K. Direct comparison between the two compounds indicates that CoAl 2O 4 is unique, not in the nature of high-temperature diffuse correlations, but rather in the nature of the frozen state below T*. Finally, the higher level of cation inversion in the MnAl 2O 4 sample indicates that this behavior is primarily an effect of greater next-nearest-neighbor exchange.« less

Revisiting the ground state of CoAl 2 O 4 : Comparison to the conventional antiferromagnet MnAl 2 O 4

DOE PAGES

MacDougall, Gregory J.; Aczel, Adam A.; Su, Yixi; ...

2016-11-17

The A-site spinel material CoAl 2O 4 is a physical realization of the frustrated diamond-lattice antiferromagnet, a model in which unique incommensurate or “spin-spiral-liquid” ground states are predicted. Our previous single-crystal neutron scattering study instead classified it as a “kinetically inhibited” antiferromagnet, where the long-ranged correlations of a collinear Néel ground state are blocked by the freezing of domain-wall motion below a first-order phase transition at T*=6.5 K. This study provides new data sets from a number of experiments, which support and expand this work in several important ways. We show that the phenomenology leading to the kinetically inhibited ordermore » is unaffected by sample measured and instrument resolution, while new low-temperature measurements reveal spin correlations are unchanging between T=2 K and 250 mK, consistent with a frozen state. Polarized diffuse neutron measurements show several interesting magnetic features, which can be entirely explained by the existence of short-ranged Néel order. Finally, and crucially, this paper presents some neutron scattering studies of single crystalline MnAl 2O 4, which acts as an unfrustrated analog to CoAl 2O 4 and shows all the hallmarks of a classical antiferromagnet with a continuous phase transition to Néel order at T N=39 K. Direct comparison between the two compounds indicates that CoAl 2O 4 is unique, not in the nature of high-temperature diffuse correlations, but rather in the nature of the frozen state below T*. Finally, the higher level of cation inversion in the MnAl 2O 4 sample indicates that this behavior is primarily an effect of greater next-nearest-neighbor exchange.« less

Numerical Simulation of Regional Changes in Ground-Water Levels and in the Freshwater-Saltwater Interface Induced by Increased Pumpage at Barbers Point Shaft, Oahu, Hawaii

USGS Publications Warehouse

Souza, William R.; Meyer, William

1995-01-01

The effect on the regional ground-water system of southern Oahu from increased pumpage at Barbers Point shaft was estimated by a numerical ground-water model developed for the Oahu Regional Aquifer Systems Analysis (RASA) study. The RASA model was updated by revising pumping and ground-water recharge data. Pumpage data used in the new simulations were based on the allocated pumping rates for 1995 as set by the State Commission on Water Resource Management. On the basis of numerical simulation, Barbers Point shaft can sustain a withdrawal rate of 4.34 million gallons per day without adversely affecting wells in the Waianae aquifer. From results of numerical simulations, it is estimated that, as a result of increasing pumpage in Barbers Point shaft by 2 million gallons per day above the 1995-allocated rate of 2.337 million gallons per day, regional declines in ground-water levels will be about 0.4 to 0.7 feet throughout the Waianae aquifer and about 0.8 ft at the shaft. The corresponding rise of the freshwater-saltwater interface, as a result of declines in ground-water levels, is estimated to be about 20 to 30 feet. Numerical simulation also indicates that changes in ground-water levels greater than about 0.1 feet do not extend across either the Waianae-Koolau unconformity or the south Schofield barrier. The model-estimated position of the freshwater-saltwater interface, as a result of additional pumpage, ranges from 500 to 860 feet below sea level in the southern and northern parts of the aquifer, respectively, and about 540 feet below sea level at the shaft. On the basis of an estimate of the thickness of the transition-zone, the freshwater lens would remain about 240 feet thick below the shaft. In addition, the estimated declines in ground-water levels throughout the aquifer are small compared with the thickness of the freshwater lens and these declines would not be expected to affect the yields of other wells in terms of quantity. Chloride concentrations in the water pumped at Barbers Point shaft were about 240 milligrams per liter in 1992. The estimated background chloride concentration is 200 to 220 milligrams per liter because of low rainfall and the contamination of recharge water from natural salt accumulation in the soil. A reduction in irrigation through 1995 is expected to reduce recharge to the aquifer from irrigation-return water and chloride concentrations associated with the irrigation water throughout the Waianae aquifer. As a result of these combined effects, chloride concentrations of water pumped from the Barbers Point shaft will likely decrease, although the length of time required for this lowering is unknown.

Leg and trunk muscle coordination and postural sway during increasingly difficult standing balance tasks in young and older adults.

PubMed

Donath, Lars; Kurz, Eduard; Roth, Ralf; Zahner, Lukas; Faude, Oliver

2016-09-01

Ageing impairs body balance and increases older adults' fall risk. Balance training can improve intrinsic fall risk factors. However, age comparisons of muscle activity responses during balance tasks are lacking. This study investigated relative muscle activity, muscle coordination and postural sway during various recommended static balance training tasks. Muscle activity (%MVC), amplitude ratios (AR) and co-activity (CAI) were determined during standing tasks for 30s (1: double limb stance on a foam surface, eyes open; 2: double limb stance on firm ground, eyes closed; 3: double limb stance, feet in step position on a foam surface, eyes open; 4: double limb stance, feet in step position on firm ground, eyes closed; 5: single limb stance on firm ground, eyes open) in 20 healthy young adults (24±2 y) and 20 older adults (73±6 y). Surface electromyography (SEMG) was applied (SENIAM guidelines) to ankle (tibialis anterior, soleus, medial gastrocnemius, peroneus longus) and thigh (vastus lateralis, vastus medialis, biceps femoris, semitendinosus) muscles (non-dominant leg). Electrodes over trunk (multifidus and internal oblique) muscles were applied bilaterally. Two- to six-fold higher levels of relative muscle activity were found in older adults for ankle (0.0002

Using ground reaction force to predict knee kinetic asymmetry following anterior cruciate ligament reconstruction.

PubMed

Dai, B; Butler, R J; Garrett, W E; Queen, R M

2014-12-01

Asymmetries in sagittal plane knee kinetics have been identified as a risk factor for anterior cruciate ligament (ACL) re-injury. Clinical tools are needed to identify the asymmetries. This study examined the relationships between knee kinetic asymmetries and ground reaction force (GRF) asymmetries during athletic tasks in adolescent patients following ACL reconstruction (ACL-R). Kinematic and GRF data were collected during a stop-jump task and a side-cutting task for 23 patients. Asymmetry indices between the surgical and non-surgical limbs were calculated for GRF and knee kinetic variables. For the stop-jump task, knee kinetics asymmetry indices were correlated with all GRF asymmetry indices (P < 0.05), except for loading rate. Vertical GRF impulse asymmetry index predicted peak knee moment, average knee moment, and knee work (R(2)  ≥ 0.78, P < 0.01) asymmetry indices. For the side-cutting tasks, knee kinetic asymmetry indices were correlated with the peak propulsion vertical GRF and vertical GRF impulse asymmetry indices (P < 0.05). Vertical GRF impulse asymmetry index predicted peak knee moment, average knee moment, and knee work (R(2)  ≥ 0.55, P < 0.01) asymmetry indices. The vertical GRF asymmetries may be a viable surrogate for knee kinetic asymmetries and therefore may assist in optimizing rehabilitation outcomes and minimizing re-injury rates. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Meetings: Issues and recent advances in soil respiration

Treesearch

K.A. Hibbard; B.E. Law

2004-01-01

The terrestrial carbon cycle is intriniscally tied to climate, hydrology, nutrient cycles, and the production of biomass through photosynthesis. Over two-thirds of terrestrial carbon is stored below ground in soils, and a significant amount of atmospheric CO2 is processed by soils every year. Thus, soil respiration is a key process that underlies...

Paramagnetic-to-nonmagnetic transition in antiperovskite nitride Cr3GeN studied by 14N-NMR and µSR

NASA Astrophysics Data System (ADS)

Takao, K.; Liu, Z.; Uji, K.; Waki, T.; Tabata, Y.; Watanabe, I.; Nakamura, H.

2017-06-01

The antiperovskite-related nitride Cr3GeN forms a tetragonal structure with the space group P\\bar{4}{2}1m at room temperature. It shows a tetragonal (P\\bar{4}{2}1m) to tetragonal (I4/mcm) structural transition with a large hysteresis at 300-400 K. The magnetic susceptibility of Cr3GeN shows Curie-Weiss type temperature dependence at high temperature, but is almost temperature-independent below room temperature. We carried out µSR and 14N-NMR microscopy measurements to reveal the magnetic ground state of Cr3GeN. Gradual muon spin relaxation, which is nearly temperature-independent below room temperature, was observed, indicating that Cr3GeN is magnetically inactive. In the 14N-NMR measurement, a quadrupole-split spectrum was obtained at around 14 K = 0. The temperature dependence of 14(1/T1) satisfies the Korringa relation. These experimental results indicate that the ground state of Cr3GeN is Pauli paramagnetic, without antiferromagnetic long-range order.

Trophic cascades, invasive species and body-size hierarchies interactively modulate climate change responses of ecotonal temperate–boreal forest

PubMed Central

Frelich, Lee E.; Peterson, Rolf O.; Dovčiak, Martin; Reich, Peter B.; Vucetich, John A.; Eisenhauer, Nico

2012-01-01

As the climate warms, boreal tree species are expected to be gradually replaced by temperate species within the southern boreal forest. Warming will be accompanied by changes in above- and below-ground consumers: large moose (Alces alces) replaced by smaller deer (Odocoileus virginianus) above-ground, and small detritivores replaced by larger exotic earthworms below-ground. These shifts may induce a cascade of ecological impacts across trophic levels that could alter the boreal to temperate forest transition. Deer are more likely to browse saplings of temperate tree species, and European earthworms favour seedlings of boreal tree species more than temperate species, potentially hindering the ability of temperate tree species to expand northwards. We hypothesize that warming-induced changes in consumers will lead to novel plant communities by changing the filter on plant species success, and that above- and below-ground cascades of trophic interactions will allow boreal tree species to persist during early phases of warming, leading to an abrupt change at a later time. The synthesis of evidence suggests that consumers can modify the climate change-induced transition of ecosystems. PMID:23007083

Aerodynamic Characteristics of Low-Aspect-Ratio Wings in Close Proximity to the Ground

NASA Technical Reports Server (NTRS)

Fink, Marvin P.; Lastinger, James L.

1961-01-01

A wind-tunnel investigation has been conducted to determine the effect of ground proximity on the aerodynamic characteristics of thick highly cambered rectangular wings with aspect ratios of 1. 2, 4, and 6. The results showed that, for these aspect ratios, as the ground war, approached all wings experienced increases in lift-curve slope and reductions in induced drag which resulted in increases in lift-drag ratio. Although an increase in lift-curve slope was obtained for all aspect ratios as the ground was approached, the lift coefficient at an angle of attack of 0 deg for any given aspect ratio remained nearly constant. The experimental results were in general agreement with Wieselsberger's ground-effect theory (NACA Technical Memorandum 77). As the wings approached the ground, there was an increase in static longitudinal stability at positive angles of attack. When operating in ground effect, all the wings had stability of height at positive angles of attack and instability of height at negative angles of attack. Wing-tip fairings on the wings with aspect ratios of 1 and 2 produced small increases in lift-drag ratio in ground effect. End plates extending only below the chord plane on the wing with an aspect ratio of 1 provided increases in lift coefficient and in lift-drag ratio in ground effect.

The First Development of Human Factors Engineering Requirements for Application to Ground Task Design for a NASA Flight Program

NASA Technical Reports Server (NTRS)

Dischinger, H. Charles, Jr.; Stambolian, Damon B.; Miller, Darcy H.

2008-01-01

The National Aeronautics and Space Administration has long applied standards-derived human engineering requirements to the development of hardware and software for use by astronauts while in flight. The most important source of these requirements has been NASA-STD-3000. While there have been several ground systems human engineering requirements documents, none has been applicable to the flight system as handled at NASA's launch facility at Kennedy Space Center. At the time of the development of previous human launch systems, there were other considerations that were deemed more important than developing worksites for ground crews; e.g., hardware development schedule and vehicle performance. However, experience with these systems has shown that failure to design for ground tasks has resulted in launch schedule delays, ground operations that are more costly than they might be, and threats to flight safety. As the Agency begins the development of new systems to return humans to the moon, the new Constellation Program is addressing this issue with a new set of human engineering requirements. Among these requirements is a subset that will apply to the design of the flight components and that is intended to assure ground crew success in vehicle assembly and maintenance tasks. These requirements address worksite design for usability and for ground crew safety.

Figure/ground segregation from temporal delay is best at high spatial frequencies.

PubMed

Kojima, H

1998-12-01

Two experiments investigated the role of spatial frequency in performance of a figure/ground segregation task based on temporal cues. Figure orientation was much easier to judge when figure and ground portions of the target were defined exclusively by random texture composed entirely of high spatial frequencies. When target components were defined by low spatial frequencies only, the task was nearly impossible except with long temporal delay between figure and ground. These results are inconsistent with the hypothesis that M-cell activity is primarily responsible for figure/ground segregation from temporal delay. Instead, these results point to a distinction between temporal integration and temporal differentiation. Additionally, the present results can be related to recent work on the binding of spatial features over time.

Accelerated ageing of blended OPC cements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quillin, K.C.; Duerden, S.L.; Majumdar, A.J.

1994-12-31

An accelerated experimental technique using high water:cement ratios has been developed to study the long term hydration of blended cements that may be used in a repository for the disposal of radioactive waste. This technique has been used to investigate the hydration reactions of Ordinary Portland Cement (OPC) blended with ground granulated blastfurnace slag (ggbs) or pulverised fuel ash (pfa). The effects of high sulphate-bearing and high carbonate-bearing ground waters on the compounds formed on hydration were investigated. Solid/solution compositional data were collected during the course of the hydration process for periods up to 2 years. Thomsonite, thaumasite, afwillite andmore » a tobermorite-like phase were found in addition to the expected cement hydration products. The pH of the aqueous solution in contact with 60 pfa:40 OPC blends hydrated at 90{degrees}C fell to below 8. This is lower than the value required to inhibit the corrosion of steel canisters in a repository. The pH of the aqueous solution in contact with OPC and 75 ggbs:25 OPC blends remained above 11, although if the ground waters in contact with the OPC/ggbs blends were periodically replaced the pH eventually fell below 10.« less

Map showing ground-water conditions in the Kaibito and Tuba City areas, Coconino and Navajo counties, Arizona, 1978

USGS Publications Warehouse

Farrar, C.D.

1978-01-01

The Kaibito and Tuba City areas include about 2,500 square miles in north-central Arizona. Ground water is obtained from the N aquifer and from alluvium. The N aquifer consists of Navajo Sandstone, Kayenta Formation, Moenave Formation, and the Lukachukai Member of the Wingate Sandstone. The main source of ground water is the Navajo Sandstone. Ground-water development has been slight in the areas. In 1977 the estimated ground-water withdrawals were about 350 acre-feet in the Kaibito area and 650 acre-feet in the Tuba City area. Water levels ranged from flowing at the land surface to 1,360 feet below the land surface. The chemical quality of the water in the N aquifer does not vary greatly in the areas. Dissolved-solids concentrations in the water range from 101 to 669 milligrams per liter but generally are less than 300 milligrams per liter. Along some of the valleys in the Kaibito and Tuba City areas, the alluvium yields water to many shallow dug wells. The water levels generally are from 5 to 15 feet below the land surface. Dissolved-solids concentrations in water from the alluvium usually are less than 600 milligrams per liter. Information shown on the map (scale 1:125,000) includes depth to water, altitude of the water level, and specific conductance and fluoride concentrations. (Woodard-USGS)

Different sources of soil CO2 respiration from a drained spruce forest and their dependence on environmental factors

NASA Astrophysics Data System (ADS)

Nousratpour, A.

2011-12-01

The annual CO2 emission from soils corresponds to a large portion of the global carbon cycle and equals 10 percent of the total atmospheric carbon pool. The total forest soil CO2 loss equals the sum of contribution from autotrophic and heterotrophic organisms. The autotrophic respiration is derived from recent photosynthates from the forest canopy and exudates via the roots. The heterotrophic respiration is less directly dependent on root presence and recently assimilated photosynthates, which points to the possibility of separate mechanisms governing the CO2 emissions. The variation of the CO2 flux from these some-what overlapping sources in the soil i.e. rhizospheric and non-rhizosperically is still not fully understood. Soil temperature and water availability in particular have often been used to explain the variation of soil CO2 efflux by using regression methods. In this experiment around 1000 hours of soil CO2-emission rates from a drained spruce forest was collected from 6 plots, among which 3 were previously root excluded. The emission rates were collected during 5 campaigns throughout the growing season along with continuous above ground and below ground temperature and water properties such as precipitation and VPD (vapor pressure deficit). The resulting matrix was analyzed using multivariate statistical model PLSr (Partial Least Squares regression). This operation reduces the dimensionality of large datasets with probable multicollinearity and helps clarify the dependence of a response factor on x- variables. In addition a time series analysis is applied to the dataset to address the time lag between below ground temperature and water properties to the above ground weather conditions such as VPD and air temperature. Mean carbon emission from the control plots (428 mg Carbon m-2 hr-1) was significantly larger than that from the root excluded plots (136 mg Carbon m-2 hr-1). During the growing season more than 2/3 of the total CO2 release was estimated to be root contribution. The results show that the activity in the rhizosphere increased with rising soil temperature, VPD and ground water depletion until a certain point. When the level of ground water depth was deeper than about 0.5 m the dependence was reversed. This effect was either the opposite or lacking in the root excluded plots, which reflects the involvement of the tree roots and the separate factors controlling the different sources of CO2.

Reagent removal of manganese from ground water

NASA Astrophysics Data System (ADS)

Brayalovsky, G.; Migalaty, E.; Naschetnikova, O.

2017-06-01

The study is aimed at the technology development of treating drinking water from ground waters with high manganese content and oxidizability. Current technologies, physical/chemical mechanisms and factors affecting in ground treatment efficiency are reviewed. Research has been conducted on manganese compound removal from ground waters with high manganese content (5 ppm) and oxidizability. The studies were carried out on granular sorbent industrial ODM-2F filters (0.7-1.5 mm fraction). It was determined that conventional reagent oxidization technologies followed by filtration do not allow us to obtain the manganese content below 0.1 ppm when treating ground waters with high oxidizability. The innovative oxidation-based manganese removal technology with continuous introduction of reaction catalytic agent is suggested. This technology is effective in alkalization up to pH 8.8-9. Potassium permanganate was used as a catalytic agent, sodium hypochlorite was an oxidizer and cauistic soda served an alkalifying agent.

Microhabitats and canopy cover moderate high summer temperatures in a fragmented Mediterranean landscape.

PubMed

Keppel, Gunnar; Anderson, Sharolyn; Williams, Craig; Kleindorfer, Sonia; O'Connell, Christopher

2017-01-01

Extreme heat events will become more frequent under anthropogenic climate change, especially in Mediterranean ecosystems. Microhabitats can considerably moderate (buffer) the effects of extreme weather events and hence facilitate the persistence of some components of the biodiversity. We investigate the microclimatic moderation provided by two important microhabitats (cavities formed by the leaves of the grass-tree Xanthorrhoea semiplana F.Muell., Xanthorrhoeaceae; and inside the leaf-litter) during the summer of 2015/16 on the Fleurieu Peninsula of South Australia. We placed microsensors inside and outside these microhabitats, as well as above the ground below the forest canopy. Grass-tree and leaf-litter microhabitats significantly buffered against high temperatures and low relative humidity, compared to ground-below-canopy sensors. There was no significant difference between grass-tree and leaf-litter temperatures: in both microhabitats, daily temperature variation was reduced, day temperatures were 1-5°C cooler, night temperatures were 0.5-3°C warmer, and maximum temperatures were up to 14.4°C lower, compared to ground-below-canopy sensors. Grass-tree and leaf-litter microhabitats moderated heat increase at an average rate of 0.24°C temperature per 1°C increase of ambient temperature in the ground-below-canopy microhabitat. The average daily variation in temperature was determined by the type (grass-tree and leaf-litter versus ground-below-canopy) of microhabitat (explaining 67%), the amount of canopy cover and the area of the vegetation fragment (together explaining almost 10% of the variation). Greater canopy cover increased the amount of microclimatic moderation provided, especially in the leaf-litter. Our study highlights the importance of microhabitats in moderating macroclimatic conditions. However, this moderating effect is currently not considered in species distribution modelling under anthropogenic climate change nor in the management of vegetation. This shortcoming will have to be addressed to obtain realistic forecasts of future species distributions and to achieve effective management of biodiversity.

Bioturbation by the Fungus-Gardening Ant, Trachymyrmex septentrionalis

PubMed Central

Tschinkel, Walter R.; Seal, Jon N.

2016-01-01

Soil invertebrates such as ants are thought to be important manipulators of soils in temperate and tropical ecosystems. The fungus gardening ant, Trachymyrmex septentrionalis, is an important agent of biomantling, that is, of depositing soil excavated from below onto the surface, and has been suggested as an agent of bioturbation (moving soil below ground) as well. The amount of bioturbation by this ant was quantified by planting queenright colonies in sand columns consisting of 5 layers of different colored sand. The amount of each color of sand deposited on the surface was determined from April to November 2015. In November, colonies were excavated and the color and amount of sand deposited below ground (mostly as backfill in chambers) was determined. Extrapolated to one ha, T. septentrionalis deposited 800 kg of sand per annum on the surface, and an additional 200 kg (17% of the total excavated) below ground. On average, this mixes 1.3% of the sand from other layers within the top meter of soil per millennium, but this mixing is unlikely to be homogeneous, and probably occurs as "hotspots" in both horizontal and vertical space. Such mixing is discussed as a challenge to sediment dating by optically stimulated luminescence (OSL). PMID:27391485

Bioturbation by the Fungus-Gardening Ant, Trachymyrmex septentrionalis.

PubMed

Tschinkel, Walter R; Seal, Jon N

2016-01-01

Soil invertebrates such as ants are thought to be important manipulators of soils in temperate and tropical ecosystems. The fungus gardening ant, Trachymyrmex septentrionalis, is an important agent of biomantling, that is, of depositing soil excavated from below onto the surface, and has been suggested as an agent of bioturbation (moving soil below ground) as well. The amount of bioturbation by this ant was quantified by planting queenright colonies in sand columns consisting of 5 layers of different colored sand. The amount of each color of sand deposited on the surface was determined from April to November 2015. In November, colonies were excavated and the color and amount of sand deposited below ground (mostly as backfill in chambers) was determined. Extrapolated to one ha, T. septentrionalis deposited 800 kg of sand per annum on the surface, and an additional 200 kg (17% of the total excavated) below ground. On average, this mixes 1.3% of the sand from other layers within the top meter of soil per millennium, but this mixing is unlikely to be homogeneous, and probably occurs as "hotspots" in both horizontal and vertical space. Such mixing is discussed as a challenge to sediment dating by optically stimulated luminescence (OSL).

A tentative protocol for measurement of radon availability from the ground

USGS Publications Warehouse

Tanner, A.B.

1988-01-01

A procedure is being tested in order to determine its suitability for assessing the intrinsic ability of the ground at a particular site to supply radon (222Rn) to a basement structure to be built on the site. The mean migration distance, multiplied by the measured radon concentration gives the "Radon Availability Number' (RAN). Measurements at sites of known indoor radon concentration suggest that RANs below 2 kBq/m2 (5x104 pCi/m2) indicate little chance of elevated indoor radon and RANs above 20 kBq/m2 (5x105 pCi/m2) indicate that elevated indoor radon is likely. The range of uncertainty and the point-to-point and seasonal variations to be expected are under investigation. -from Author

Genotypic Diversity for Biomass Accumulation and Shoot-Root Allometry in the Grass Brachypodium distachyon

NASA Astrophysics Data System (ADS)

Jansson, C.; Handakumbura, P. P.; Fortin, D.; Stanfill, B.; Rivas-Ubach, A.

2017-12-01

Predicting carbon uptake, assimilation and allocation for current and future biogeographical environments, including climate, is critical for our ability to select and/or design plant genotypes to meet increasing demand for plant biomass going into food, feed and energy production, while at the same time maintain or increase soil organic matter (SOM for soil fertility and carbon storage, and reduce emission of greenhouse gasses. As has been demonstrated for several plant species allometric relationships may differ between plant genotypes. Exploring plant genotypic diversity for biomass accumulation and allometry will potentially enable selection of genotypes with high CO2 assimilation and favorable allocation of recent photosynthate into above-ground and below-ground biomass. We are investigating genotypic diversity for PFTs in natural accessions of the annual C3 grass Brachypodium distachyon under current and future climate scenarios and how genotypic diversity correlates with metabolite profiles in aboveground and below-ground biomass. In the current study, we compare effects from non-stressed and drought conditions on biomass accumulation and shoot-root allometry.

78 FR 11632 - Record of Decision for Land Acquisition and Airspace Establishment To Support Large-Scale Marine...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-19

... Establishment To Support Large-Scale Marine Air Ground Task Force Live- Fire and Maneuver Training at the Marine...), announces its decision to establish a large-scale Marine Air Ground Task Force (MAGTF) training facility at... through the Federal Aviation Administration the establishment and modification of military Special Use...

Tropical Engineering. Design Manual-11.1.

DTIC Science & Technology

1980-03-01

fication TS-15250 for cold piping below 35 degrees F. Cellular glass 11.1-75 insulation only shall be used. Flexible unicellular insulation shall not be...11.1-71 2. Materials .........o......................................11.1-71 a. Underground Water Piping ...11.1-71 b. Protective Coating for Copper Tubing .................11.1-71 c. Above-ground Piping ................................. 11.1

Space applications of Automation, Robotics and Machine Intelligence Systems (ARAMIS). Volume 2: Space projects overview

NASA Technical Reports Server (NTRS)

Miller, R. H.; Minsky, M. L.; Smith, D. B. S.

1982-01-01

Applications of automation, robotics, and machine intelligence systems (ARAMIS) to space activities, and their related ground support functions are studied so that informed decisions can be made on which aspects of ARAMIS to develop. The space project breakdowns, which are used to identify tasks ('functional elements'), are described. The study method concentrates on the production of a matrix relating space project tasks to pieces of ARAMIS.

Earth melter with rubble walls and method of use

DOEpatents

Chapman, Chris C.

1998-01-01

The present invention is an improvement to the earth melter described and claimed in U.S. Pat. No. 5,443,618. The improvement is the use of rubble for retaining walls. More specifically, the retaining walls rest on ground level and extend above ground level piling rubble around a melt zone. A portion of the melter may be below grade wherein sidewalls are formed by the relatively undisturbed native soil or rock, and the rubble may be used as a backfill liner for the below grade sidewalls.

Figure-ground segmentation can occur without attention.

PubMed

Kimchi, Ruth; Peterson, Mary A

2008-07-01

The question of whether or not figure-ground segmentation can occur without attention is unresolved. Early theorists assumed it can, but the evidence is scant and open to alternative interpretations. Recent research indicating that attention can influence figure-ground segmentation raises the question anew. We examined this issue by asking participants to perform a demanding change-detection task on a small matrix presented on a task-irrelevant scene of alternating regions organized into figures and grounds by convexity. Independently of any change in the matrix, the figure-ground organization of the scene changed or remained the same. Changes in scene organization produced congruency effects on target-change judgments, even though, when probed with surprise questions, participants could report neither the figure-ground status of the region on which the matrix appeared nor any change in that status. When attending to the scene, participants reported figure-ground status and changes to it highly accurately. These results clearly demonstrate that figure-ground segmentation can occur without focal attention.

Experimental warming in a dryland community reduced plant photosynthesis and soil CO2 efflux although the relationship between the fluxes remained unchanged

USGS Publications Warehouse

Wertin, Timothy M.; Belnap, Jayne; Reed, Sasha C.

2016-01-01

1. Drylands represent our planet's largest terrestrial biome and, due to their extensive area, maintain large stocks of carbon (C). Accordingly, understanding how dryland C cycling will respond to climate change is imperative for accurately forecasting global C cycling and future climate. However, it remains difficult to predict how increased temperature will affect dryland C cycling, as substantial uncertainties surround the potential responses of the two main C fluxes: plant photosynthesis and soil CO2 efflux. In addition to a need for an improved understanding of climate effects on individual dryland C fluxes, there is also notable uncertainty regarding how climate change may influence the relationship between these fluxes.2. To address this important knowledge gap, we measured a growing season's in situphotosynthesis, plant biomass accumulation, and soil CO2 efflux of mature Achnatherum hymenoides (a common and ecologically important C3 bunchgrass growing throughout western North America) exposed to ambient or elevated temperature (+2°C above ambient, warmed via infrared lamps) for three years.3. The 2°C increase in temperature caused a significant reduction in photosynthesis, plant growth, and soil CO2 efflux. Of important note, photosynthesis and soil respiration appeared tightly coupled and the relationship between these fluxes was not altered by the elevated temperature treatment, suggesting C fixation's strong control of both above-ground and below-ground dryland C cycling. Leaf water use efficiency was substantially increased in the elevated temperature treatment compared to the control treatment.4. Taken together, our results suggest notable declines in photosynthesis with relatively subtle warming, reveal strong coupling between above- and below-ground C fluxes in this dryland, and highlight temperature's strong effect on fundamental components of dryland C and water cycles.

Allocation, morphology, physiology, architecture: the multiple facets of plant above- and below-ground responses to resource stress.

PubMed

Freschet, Grégoire T; Violle, Cyrille; Bourget, Malo Y; Scherer-Lorenzen, Michael; Fort, Florian

2018-06-01

Plants respond to resource stress by changing multiple aspects of their biomass allocation, morphology, physiology and architecture. To date, we lack an integrated view of the relative importance of these plastic responses in alleviating resource stress and of the consistency/variability of these responses among species. We subjected nine species (legumes, forbs and graminoids) to nitrogen and/or light shortages and measured 11 above-ground and below-ground trait adjustments critical in the alleviation of these stresses (plus several underlying traits). Nine traits out of 11 showed adjustments that improved plants' potential capacity to acquire the limiting resource at a given time. Above ground, aspects of plasticity in allocation, morphology, physiology and architecture all appeared important in improving light capture, whereas below ground, plasticity in allocation and physiology were most critical to improving nitrogen acquisition. Six traits out of 11 showed substantial heterogeneity in species plasticity, with little structuration of these differences within trait covariation syndromes. Such comprehensive assessment of the complex nature of phenotypic responses of plants to multiple stress factors, and the comparison of plant responses across multiple species, makes a clear case for the high (but largely overlooked) diversity of potential plastic responses of plants, and for the need to explore the potential rules structuring them. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Phosphorus deficiency affects the allocation of below-ground resources to combined cluster roots and nodules in Lupinus albus.

PubMed

Thuynsma, Rochelle; Valentine, Alex; Kleinert, Aleysia

2014-02-15

Lupins can rely on both cluster roots and nodules for P acquisition and biological nitrogen fixation (BNF), respectively. The resource allocation (C, N and P) between cluster roots and nodules has been largely understudied during P-deficient conditions. The aim of this investigation was therefore to determine the changes in resource allocation between these organs during fluctuations in P supply. Lupinus albus was cultivated in sand culture for 3 weeks, with either sufficient (2 mM high) or limiting (0.1 mM low) P supply. Although variation on P supply had no effect on the total biomass, there were significant differences in specialised below-ground organ allocation to cluster roots and nodule formation. Cluster root formation and the associated C-costs increased during low P supply, but at sufficient P-supply the construction and growth respiration costs of cluster roots declined along with their growth. In contrast to the cluster root decline at high P supply, there was an increase in nodule growth allocation and corresponding C-costs. However, this was not associated with an increase in BNF. Since cluster roots were able to increase P acquisition under low P conditions, this below-ground investment may also have benefited the P nutrition of nodules. These findings provide evidence that when lupins acquire N via BNF in their nodules, there may be a trade-off in resource allocation between cluster roots and nodules. Copyright © 2013 Elsevier GmbH. All rights reserved.

Magnetic relaxation behaviour in Pr{sub 2}NiSi{sub 3}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pakhira, Santanu, E-mail: santanupakhira20006@gmail.com; Mazumdar, Chandan; Ranganathan, R.

2016-05-06

Time dependent isothemal remanent magnetizatin (IRM) behaviour for polycrystalline compound Pr{sub 2}NiSi{sub 3} have been studied below its characteristic temperature. The compound undergoes slow magnetic relaxation with time. Along with competing interaction, non-magnetic atom disorder plays an important role in formation of non-equilibrium glassy like ground state for this compound.

Tricholoma matsutake in a natural Pinus densiflora forest: correspondence between above- and below-ground genets, association with multiple host trees and alteration of existing ectomycorrhizal communities.

PubMed

Lian, Chunlan; Narimatsu, Maki; Nara, Kazuhide; Hogetsu, Taizo

2006-01-01

Tricholoma matsutake (matsutake) is an ectomycorrhizal (ECM) fungus that produces economically important mushrooms in Japan. Here, we use microsatellite markers to identify genets of matsutake sporocarps and below-ground ECM tips, as well as associated host genotypes of Pinus densiflora. We also studied ECM fungal community structure inside, beneath and outside the matsutake fairy rings, using morphological and internal transcribed spacer (ITS) polymorphism analysis. Based on sporocarp samples, one to four genets were found within each fairy ring, and no genetic differentiation among six sites was detected. Matsutake ECM tips were only found beneath fairy rings and corresponded with the genotypes of the above-ground sporocarps. We detected nine below-ground matsutake genets, all of which colonized multiple pine trees (three to seven trees per genet). The ECM fungal community beneath fairy rings was species-poor and significantly differed from those inside and outside the fairy rings. We conclude that matsutake genets occasionally establish from basidiospores and expand on the root systems of multiple host trees. Although matsutake mycelia suppress other ECM fungi during expansion, most of them may recover after the passage of the fairy rings.

A below-ground herbivore shapes root defensive chemistry in natural plant populations.

PubMed

Huber, Meret; Bont, Zoe; Fricke, Julia; Brillatz, Théo; Aziz, Zohra; Gershenzon, Jonathan; Erb, Matthias

2016-03-30

Plants display extensive intraspecific variation in secondary metabolites. However, the selective forces shaping this diversity remain often unknown, especially below ground. Using Taraxacum officinale and its major native insect root herbivore Melolontha melolontha, we tested whether below-ground herbivores drive intraspecific variation in root secondary metabolites. We found that high M. melolontha infestation levels over recent decades are associated with high concentrations of major root latex secondary metabolites across 21 central European T. officinale field populations. By cultivating offspring of these populations, we show that both heritable variation and phenotypic plasticity contribute to the observed differences. Furthermore, we demonstrate that the production of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) is costly in the absence, but beneficial in the presence of M. melolontha, resulting in divergent selection of TA-G. Our results highlight the role of soil-dwelling insects for the evolution of plant defences in nature. © 2016 The Author(s).

Residual standard deviation: Validation of a new measure of dual-task cost in below-knee prosthesis users.

PubMed

Howard, Charla L; Wallace, Chris; Abbas, James; Stokic, Dobrivoje S

2017-01-01

We developed and evaluated properties of a new measure of variability in stride length and cadence, termed residual standard deviation (RSD). To calculate RSD, stride length and cadence are regressed against velocity to derive the best fit line from which the variability (SD) of the distance between the actual and predicted data points is calculated. We examined construct, concurrent, and discriminative validity of RSD using dual-task paradigm in 14 below-knee prosthesis users and 13 age- and education-matched controls. Subjects walked first over an electronic walkway while performing separately a serial subtraction and backwards spelling task, and then at self-selected slow, normal, and fast speeds used to derive the best fit line for stride length and cadence against velocity. Construct validity was demonstrated by significantly greater increase in RSD during dual-task gait in prosthesis users than controls (group-by-condition interaction, stride length p=0.0006, cadence p=0.009). Concurrent validity was established against coefficient of variation (CV) by moderate-to-high correlations (r=0.50-0.87) between dual-task cost RSD and dual-task cost CV for both stride length and cadence in prosthesis users and controls. Discriminative validity was documented by the ability of dual-task cost calculated from RSD to effectively differentiate prosthesis users from controls (area under the receiver operating characteristic curve, stride length 0.863, p=0.001, cadence 0.808, p=0.007), which was better than the ability of dual-task cost CV (0.692, 0.648, respectively, not significant). These results validate RSD as a new measure of variability in below-knee prosthesis users. Future studies should include larger cohorts and other populations to ascertain its generalizability. Copyright © 2016 Elsevier B.V. All rights reserved.

Radon exposures in a Jerusalem public school.

PubMed Central

Richter, E D; Neeman, E; Fischer, I; Berdugo, M; Westin, J B; Kleinstern, J; Margaliot, M

1997-01-01

In December 1995, ambient radon levels exceeding 10,000 Bq/m3 were measured in a basement shelter workroom of a multilevel East Talpiot, Jerusalem, public elementary school (six grades, 600 students). The measurements were taken after cancers (breast and multiple myeloma) were diagnosed in two workers who spent their workdays in basement rooms. The school was located on a hill that geologic maps show to be rich in phosphate deposits, which are a recognized source for radon gas and its daughter products. Levels exceeding 1000,000 Bq/m3 were measured at the mouth of a pipe in the basement shelter workroom, the major point of radon entry. The school was closed and charcoal and electret ion chamber detectors were used to carry out repeated 5-day measurements in all rooms in the multilevel building over a period of several months. Radon concentrations were generally higher in rooms in the four levels of the building that were below ground level. There were some ground-level rooms in the building in which levels reached up to 1300 Bq/m3. In rooms above ground level, however, peak levels did not exceed 300 Bq/m3. Exposure control based on sealing and positive pressure ventilation was inadequate. These findings suggested that radon diffused from highly contaminated basement and ground-floor rooms to other areas of the building and that sealing off the source may have led to reaccumulation of radon beneath the building. Later, subslab venting of below-ground radon pockets to the outside air was followed by more sustained reductions in indoor radon levels to levels below 75 Bq/m3. Even so, radon accumulated in certain rooms when the building was closed. This sentinel episode called attention to the need for a national radon policy requiring threshold exposure levels for response and control. A uniform nationwide standard for school buildings below 75 Bq/m3 level was suggested after considering prudent avoidance, the controversies over risk assessment of prolonged low-level exposures in children, and the fact that exposures in most locations in the Talpiot school could be reduced below this level. Proposal of this stringent standard stimulated the search for a strategy of risk control and management based on control at the source. This strategy was more effective and probably more cost effective than one based on suppression of exposure based on sealing and ventilation. Because many Israeli areas and much of the West Bank area of the Palestinian National Authority sit on the same phosphate deposits, regional joint projects for surveillance and control may be indicated. Images Figure 1. Figure 2. PMID:9467053

Geometric Magnetic Frustration in Li3Mg2OsO6 Studied with Muon Spin Relaxation

NASA Astrophysics Data System (ADS)

Carlo, J. P.; Derakhshan, S.; Greedan, J. E.

Geometric frustration manifests when the spatial arrangement of ions inhibits magnetic order. Typically associated with antiferromagnetically (AF)-correlated moments on triangular or tetrahedral lattices, frustration occurs in a variety of structures and systems, resulting in rich phase diagrams and exotic ground states. As a window to exotic physics revealed by the cancellation of normally dominant interactions, the research community has taken great interest in frustrated systems. One family of recent interest are the rock-salt ordered oxides A5BO6, in which the B sites are occupied by magnetic ions comprising a network of interlocked tetrahedra, and nonmagnetic ions on the A sites control the B oxidation state through charge neutrality. Here we will discuss studies of Li3Mg2OsO6 using muon spin relaxation (μSR), a highly sensitive local probe of magnetism. Previous studies of this family included Li5OsO6, which exhibits AF order below 50K with minimal evidence for frustration, and Li4MgReO6, which exhibits glassy magnetism. Li3Mg2RuO6, meanwhile, exhibits long-range AF, with the ordering temperature suppressed by frustration. But its isoelectronic twin, Li3Mg2OsO6 (5d3 vs. 4d3) exhibits very different behavior, revealed by μSR to be a glassy ground state below 12K. Understanding why such similar systems exhibit diverse ground-state behavior is key to understanding the nature of geometric magnetic frustration. Financial support from the Research Corporation for Science Advancement.

Raising L2 Listeners' Metacognitive Awareness: A Sociocultural Theory Perspective

ERIC Educational Resources Information Center

Cross, Jeremy

2010-01-01

Grounded in sociocultural theory, this article outlines a small-scale study exploring metacognitive awareness of second language (L2) listening. In each of five lessons, six pairs of advanced-level, adult, Japanese, EFL learners participated in a sequence of tasks involving the explicit verbalisation of strategies as part of a pedagogical cycle…

Tethered Pyrotechnic Apparatus for Acquiring a Ground Sample

NASA Technical Reports Server (NTRS)

Jones, Jack; Zimmerman, Wayne; Wu, Jiunn Jenq; Badescu, Mircea; Sherrit, Stewart

2009-01-01

A proposed alternative design for the balloon-borne ground-sampling system described in the immediately preceding article would not rely on free fall to drive a harpoonlike sample-collecting device into the ground. Instead, the harpoon-like sample-collecting device would be a pyrotechnically driven, tethered projectile. The apparatus would include a tripod that would be tethered to the gondola. A gun for shooting the projectile into the ground would be mounted at the apex of the tripod. The gun would include an electronic trigger circuit, a chamber at the breech end containing a pyrotechnic charge, and a barrel. A sabot would be placed in the barrel just below the pyrotechnic charge, and the tethered projectile would be placed in the barrel just below the sabot. The tripod feet would be equipped with contact sensors connected to the trigger circuit. In operation, the tripod would be lowered to the ground on its tether. Once contact with the ground was detected by the sensors on all three tripod feet, the trigger circuit would fire the pyrotechnic charge to drive the projectile into the ground. (Requiring contact among all three tripod feet and the ground would ensure that the projectile would be fired into the ground, rather than up toward the gondola or the balloon.) The tethered projectile would then be reeled back up to the gondola for analysis of the sample.

a Study of Co-Planing Technology of Spaceborne, Airborne and Ground Remote Sensing Detecting Resource, Driven by Disaster Emergency Task

NASA Astrophysics Data System (ADS)

Yu, F.; Chen, H.; Tu, K.; Wen, Q.; He, J.; Gu, X.; Wang, Z.

2018-04-01

Facing the monitoring needs of emergency responses to major disasters, combining the disaster information acquired at the first time after the disaster and the dynamic simulation result of the disaster chain evolution process, the overall plan for coordinated planning of spaceborne, airborne and ground observation resources have been designed. Based on the analysis of the characteristics of major disaster observation tasks, the key technologies of spaceborne, airborne and ground collaborative observation project are studied. For different disaster response levels, the corresponding workflow tasks are designed. On the basis of satisfying different types of disaster monitoring demands, the existing multi-satellite collaborative observation planning algorithms are compared, analyzed, and optimized.

Warming-related increases in soil CO2 efflux are explained by increased below-ground carbon flux

Treesearch

Christian P. Giardina; Creighton M. Litton; Susan E. Crow; Gregory P Asner

2014-01-01

The universally observed exponential increase in soil-surface CO2 effux (‘soil respiration’; FS) with increasing temperature has led to speculation that global warming will accelerate soil organic carbon (SOC) decomposition, reduce SOC storage, and drive a positive feedback to future warming. However, interpreting temperature–FS relationships,...

Effects of changing environmental conditions on synthetic aperture radar backscattering coefficient, scattering mechanisms, and class separability in a forest area

NASA Astrophysics Data System (ADS)

Mahdavi, Sahel; Maghsoudi, Yasser; Amani, Meisam

2017-07-01

Environmental conditions have considerable effects on synthetic aperture radar (SAR) imagery. Therefore, assessing these effects is important for obtaining accurate and reliable results. In this study, three series of RADARSAT-2 SAR images were evaluated. In each of these series, the sensor configuration was fixed, but the environmental conditions differed. The effects of variable environmental conditions were also investigated on co- and cross-polarized backscattering coefficients, Freeman-Durden scattering contributions, and the pedestal height in different classes of a forest area in Ottawa, Ontario. It was observed that the backscattering coefficient of wet snow was up to 2 dB more than that of dry snow. The absence of snow also caused a decrease of up to 3 dB in the surface scattering of ground and up to 5 dB in that of trees. In addition, the backscatter coefficients of ground vegetation, hardwood species, and softwood species were more similar at temperatures below 0°C than those at temperatures above 0°C. Moreover, the pedestal height was generally greater at temperatures above 0°C than at temperatures below 0°C. Finally, the highest class separability was observed when the temperature was at or above 0°C and there was no snow on the ground or trees.

A Game-Theoretic Model of Grounding for Referential Communication Tasks

ERIC Educational Resources Information Center

Thompson, William

2009-01-01

Conversational grounding theory proposes that language use is a form of rational joint action, by which dialog participants systematically and collaboratively add to their common ground of shared knowledge and beliefs. Following recent work applying "game theory" to pragmatics, this thesis develops a game-theoretic model of grounding that…

Don't Look down: Emotional Arousal Elevates Height Perception

ERIC Educational Resources Information Center

Stefanucci, Jeanine K.; Storbeck, Justin

2009-01-01

In a series of experiments, it was found that emotional arousal can influence height perception. In Experiment 1, participants viewed either arousing or nonarousing images before estimating the height of a 2-story balcony and the size of a target on the ground below the balcony. People who viewed arousing images overestimated height and target…

FeRh ground state and martensitic transformation

NASA Astrophysics Data System (ADS)

Zarkevich, Nikolai A.; Johnson, Duane D.

2018-01-01

Cubic B 2 FeRh exhibits a metamagnetic transition [(111) antiferromagnet (AFM) to ferromagnet (FM)] around 353 K and remains structurally stable at higher temperatures. However, the calculated zero-Kelvin phonons of AFM FeRh exhibit imaginary modes at M points in the Brillouin zone, indicating a premartensitic instability, which is a precursor to a martensitic transformation at low temperatures. Combining electronic-structure calculations with ab initio molecular dynamics, conjugate gradient relaxation, and the solid-state nudged-elastic band methods, we predict that AFM B 2 FeRh becomes unstable at ambient pressure and transforms without a barrier to an AFM(111) orthorhombic (martensitic) ground state below 90 ±10 K . We also consider competing structures, in particular, a tetragonal AFM(100) phase that is not the global ground state, as proposed [Phys. Rev. B 94, 180407(R) (2016), 10.1103/PhysRevB.94.180407], but a constrained solution.

Autonomous Sensorweb Operations for Integrated Space, In-Situ Monitoring of Volcanic Activity

NASA Technical Reports Server (NTRS)

Chien, Steve A.; Doubleday, Joshua; Kedar, Sharon; Davies, Ashley G.; Lahusen, Richard; Song, Wenzhan; Shirazi, Behrooz; Mandl, Daniel; Frye, Stuart

2010-01-01

We have deployed and demonstrated operations of an integrated space in-situ sensorweb for monitoring volcanic activity. This sensorweb includes a network of ground sensors deployed to the Mount Saint Helens volcano as well as the Earth Observing One spacecraft. The ground operations and space operations are interlinked in that ground-based intelligent event detections can cause the space segment to acquire additional data via observation requests and space-based data acquisitions (thermal imagery) can trigger reconfigurations of the ground network to allocate increased bandwidth to areas of the network best situated to observe the activity. The space-based operations are enabled by an automated mission planning and tasking capability which utilizes several Opengeospatial Consortium (OGC) Sensorweb Enablement (SWE) standards which enable acquiring data, alerts, and tasking using web services. The ground-based segment also supports similar protocols to enable seamless tasking and data delivery. The space-based segment also supports onboard development of data products (thermal summary images indicating areas of activity, quicklook context images, and thermal activity alerts). These onboard developed products have reduced data volume (compared to the complete images) which enables them to be transmitted to the ground more rapidly in engineering channels.

Figure-ground segregation at contours: a neural mechanism in the visual cortex of the alert monkey.

PubMed

Baumann, R; van der Zwan, R; Peterhans, E

1997-06-01

An important task of vision is the segregation of figure and ground in situations of spatial occlusion. Psychophysical evidence suggests that the depth order at contours is defined early in visual processing. We have analysed this process in the visual cortex of the alert monkey. The animals were trained on a visual fixation task which reinforced foveal viewing. During periods of active visual fixation, we recorded the responses of single neurons in striate and prestriate cortex (areas V1, V2, and V3/V3A). The stimuli mimicked situations of spatial occlusion, usually a uniform light (or dark) rectangle overlaying a grating texture of opposite contrast. The direction of figure and ground at the borders of these rectangles was defined by the direction of the terminating grating lines (occlusion cues). Neuronal responses were analysed with respect to figure-ground direction and contrast polarity at such contours. Striate neurons often failed to respond to such stimuli, or were selective for contrast polarity; others were non-selective. Some neurons preferred a certain combination of figure-ground direction and contrast polarity. These neurons were rare both in striate and prestriate cortex. The majority of neurons signalled figure-ground direction independent of contrast polarity. These neurons were only found in prestriate cortex. We explain these responses in terms of a model which also explains neuronal signals of illusory contours. These results suggest that occlusion cues are used at an early level of processing to segregate figure and ground at contours.

Root zone chemical ecology: new techniques for below grounf sampling and mass spectrometric analyses of volatile semiochemicals

USDA-ARS?s Scientific Manuscript database

The ban of methyl bromide as a soil fumigant has led to an urgent need to develop novel methods of control of soil-dwelling pests. The use of semiochemicals for below-ground insect and nematode control is one such novel avenue of research. New technologies to study semiochemically mediated below-g...

1988 Hanford riverbank springs characterization report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dirkes, R.L.

1990-12-01

This reports presents the results of a special study undertaken to characterize the riverbank springs (i.e., ground-water seepage) entering the Columbia River along the Hanford Site. Radiological and nonradiological analyses were performed. River water samples were also analyzed from upstream and downstream of the Site as well as from the immediate vicinity of the springs. In addition, irrigation return water and spring water entering the river along the shoreline opposite Hanford were analyzed. Hanford-origin contaminants were detected in spring water entering the Columbia River along the Hanford Site. The type and concentrations of contaminants in the spring water were similarmore » to those known to exist in the ground water near the river. The location and extent of the contaminated discharges compared favorably with recent ground-water reports and predictions. Spring discharge volumes remain very small relative to the flow of the Columbia. Downstream river sampling demonstrates the impact of ground-water discharges to be minimal, and negligible in most cases. Radionuclide concentrations were below US Department of Energy Derived Concentration Guides (DCGs) with the exception {sup 90}Sr near the 100-N Area. Tritium, while below the DCG, was detected at concentrations above the US Environmental Protection Agency drinking water standards in several springs. All other radionuclide concentrations were below drinking water standards. Nonradiological contaminants were generally undetectable in the spring water. River water contaminant concentrations, outside of the immediate discharge zones, were below drinking water standards in all cases. 19 refs., 5 figs., 12 tabs.« less

Running the figure to the ground: figure-ground segmentation during visual search.

PubMed

Ralph, Brandon C W; Seli, Paul; Cheng, Vivian O Y; Solman, Grayden J F; Smilek, Daniel

2014-04-01

We examined how figure-ground segmentation occurs across multiple regions of a visual array during a visual search task. Stimuli consisted of arrays of black-and-white figure-ground images in which roughly half of each image depicted a meaningful object, whereas the other half constituted a less meaningful shape. The colours of the meaningful regions of the targets and distractors were either the same (congruent) or different (incongruent). We found that incongruent targets took longer to locate than congruent targets (Experiments 1, 2, and 3) and that this segmentation-congruency effect decreased when the number of search items was reduced (Experiment 2). Furthermore, an analysis of eye movements revealed that participants spent more time scrutinising the target before confirming its identity on incongruent trials than on congruent trials (Experiment 3). These findings suggest that the distractor context influences target segmentation and detection during visual search. Copyright © 2014 Elsevier B.V. All rights reserved.

Interpretation of aeromagnetic data over Abeokuta and its environs, Southwest Nigeria, using spectral analysis (Fourier transform technique)

NASA Astrophysics Data System (ADS)

Olurin, Oluwaseun T.; Ganiyu, Saheed A.; Hammed, Olaide S.; Aluko, Taiwo J.

2016-10-01

This study presents the results of spectral analysis of magnetic data over Abeokuta area, Southwestern Nigeria, using fast Fourier transform (FFT) in Microsoft Excel. The study deals with the quantitative interpretation of airborne magnetic data (Sheet No. 260), which was conducted by the Nigerian Geological Survey Agency in 2009. In order to minimise aliasing error, the aeromagnetic data was gridded at spacing of 1 km. Spectral analysis technique was used to estimate the magnetic basement depth distributed at two levels. The result of the interpretation shows that the magnetic sources are mainly distributed at two levels. The shallow sources (minimum depth) range in depth from 0.103 to 0.278 km below ground level and are inferred to be due to intrusions within the region. The deeper sources (maximum depth) range in depth from 2.739 to 3.325 km below ground and are attributed to the underlying basement.

Ertl and Non-Ertl amputees exhibit functional biomechanical differences during the sit-to-stand task.

PubMed

Ferris, Abbie E; Christiansen, Cory L; Heise, Gary D; Hahn, David; Smith, Jeremy D

2017-05-01

People with transtibial amputation stand ~50times/day. There are two general approaches to transtibial amputation: 1) distal tibia and fibula union using a "bone-bridge" (Ertl), 2) non-union of the tibia and fibula (Non-Ertl). The Ertl technique may improve functional outcomes by increasing the end-bearing ability of the residual limb. We hypothesized individuals with an Ertl would perform a five-time sit-to-stand task faster through greater involvement/end-bearing of the affected limb. Ertl (n=11) and Non-Ertl (n=7) participants sat on a chair with each foot on separate force plates and performed the five-time sit-to-stand task. A symmetry index (intact vs affected limbs) was calculated using peak ground reaction forces. The Ertl group performed the task significantly faster (9.33s (2.66) vs 13.27 (2.83)s). Symmetry index (23.33 (23.83)% Ertl, 36.53 (13.51)% Non-Ertl) indicated the intact limb for both groups produced more force than the affected limb. Ertl affected limb peak ground reaction forces were significantly larger than the Non-Ertl affected limb. Peak knee power and net work of the affected limb were smaller than their respective intact limb for both groups. The Ertl intact limb produced significantly greater peak knee power and net work than the Non-Ertl intact knee. Although loading asymmetries existed between the intact and affected limb of both groups, the Ertl group performed the task ~30% faster. This was driven by greater power and work production of the Ertl intact limb knee. Our results suggest that functional differences exist between the procedures. Copyright © 2017 Elsevier Ltd. All rights reserved.

Selenium mobilization during a flood experiment in a contaminated wetland: Stewart Lake Waterfowl Management Area, Utah

USGS Publications Warehouse

Naftz, D.L.; Yahnke, J.; Miller, J.; Noyes, S.

2005-01-01

Constructed and natural wetlands can accumulate elevated levels of Se; however, few data are available on cost-effective methods for remobilization and removal of Se from these areas. A field experiment was conducted to assess the effectiveness of flooding on the removal of Se from dry surface sediments. The 83-m2 flood-experiment plot contained 10 monitoring wells, a water-quality minimonitor (continuous measurement of pH, specific conductance, water temperature, and dissolved O2), a down-hole Br electrode, and 2 pressure transducers. Flooding was initiated on August 27, 2002, and a Br tracer was added to water delivered through a pipeline to the flood plot during the first 1.2 h. Standing water depth in the flood plot was maintained at 0.3 m through September 1, 2002. The Br tracer data indicate a dual porosity system that includes fracture (mud cracks) and matrix flow components. Mean vertical water velocities for the matrix flow component were estimated to range from 0.002 to 0.012 m/h. Dissolved (less than 0.45 ??m) Se increased from pre-flood concentrations of less than 10 ??g/L to greater than 800 ??g/L during flooding in samples from deep (2.0 m below land surface) ground water. Selenium concentrations exceeded 5500 ??g/L in samples from shallow (0.8 m below land surface) ground water. Ratios of Se to Br in water samples indicate that Se moved conservatively during the experiment and was derived from leaching of near-surface sediments. Cumulative Se flux to the deep ground water during the experiment ranged from 9.0 to 170 mg/m2. Pre- and post-flood surface soil sampling indicated a mean Se flux of 720 mg/m2 through the top 15 cm of soil. Ground-water samples collected 8 months after termination of the flood experiment contained Se concentrations of less than 20 ??g/L. The minimonitor data indicate a rapid return to chemically reducing conditions in the deep ground water, limiting the mobility of the Se dissolved in the water pulse introduced during the flood experiment. Ratios of Se to Br in deep ground-water samples collected 8 months after the experiment confirmed the removal of Se from the aqueous phase. Based on the median Se flux rate estimated during the experiment of 0.65 mg/h/m2 (n = 52), 7 flooding cycles would be required to meet the 4 ??g/g remediation goal in surface soils from the SLWMA wetland.

Task driven optimal leg trajectories in insect-scale legged microrobots

NASA Astrophysics Data System (ADS)

Doshi, Neel; Goldberg, Benjamin; Jayaram, Kaushik; Wood, Robert

Origami inspired layered manufacturing techniques and 3D-printing have enabled the development of highly articulated legged robots at the insect-scale, including the 1.43g Harvard Ambulatory MicroRobot (HAMR). Research on these platforms has expanded its focus from manufacturing aspects to include design optimization and control for application-driven tasks. Consequently, the choice of gait selection, body morphology, leg trajectory, foot design, etc. have become areas of active research. HAMR has two controlled degrees-of-freedom per leg, making it an ideal candidate for exploring leg trajectory. We will discuss our work towards optimizing HAMR's leg trajectories for two different tasks: climbing using electroadhesives and level ground running (5-10 BL/s). These tasks demonstrate the ability of single platform to adapt to vastly different locomotive scenarios: quasi-static climbing with controlled ground contact, and dynamic running with un-controlled ground contact. We will utilize trajectory optimization methods informed by existing models and experimental studies to determine leg trajectories for each task. We also plan to discuss how task specifications and choice of objective function have contributed to the shape of these optimal leg trajectories.

Hemispatial neglect and serial order in verbal working memory.

PubMed

Antoine, Sophie; Ranzini, Mariagrazia; van Dijck, Jean-Philippe; Slama, Hichem; Bonato, Mario; Tousch, Ann; Dewulf, Myrtille; Bier, Jean-Christophe; Gevers, Wim

2018-01-09

Working memory refers to our ability to actively maintain and process a limited amount of information during a brief period of time. Often, not only the information itself but also its serial order is crucial for good task performance. It was recently proposed that serial order is grounded in spatial cognition. Here, we compared performance of a group of right hemisphere-damaged patients with hemispatial neglect to healthy controls in verbal working memory tasks. Participants memorized sequences of consonants at span level and had to judge whether a target consonant belonged to the memorized sequence (item task) or whether a pair of consonants were presented in the same order as in the memorized sequence (order task). In line with this idea that serial order is grounded in spatial cognition, we found that neglect patients made significantly more errors in the order task than in the item task compared to healthy controls. Furthermore, this deficit seemed functionally related to neglect severity and was more frequently observed following right posterior brain damage. Interestingly, this specific impairment for serial order in verbal working memory was not lateralized. We advance the hypotheses of a potential contribution to the deficit of serial order in neglect patients of either or both (1) reduced spatial working memory capacity that enables to keep track of the spatial codes that provide memorized items with a positional context, (2) a spatial compression of these codes in the intact representational space. © 2018 The British Psychological Society.

Hydrogeology and ground-water quality of the Chromic Acid Pit site, US Army Air Defense Artillery Center and Fort Bliss, El Paso, Texas

USGS Publications Warehouse

Abeyta, Cynthia G.; Thomas, C.L.

1996-01-01

The Chromic Acid Pit site is an inactive waste disposal site that is regulated by the Resource Conservation and Recovery Act of 1976. The 2.2-cubic-yard cement-lined pit was operated from 1980 to 1983 by a contractor to the U.S. Army Air Defense Artillery Center and Fort Bliss. The pit, located on the Fort Bliss military reservation, in El Paso, Texas, was used for disposal and evaporation of chromic acid waste generated from chrome plating operations. The site was certified closed in 1989 and the Texas Natural Resources Conservation Commission issued Permit Number HW-50296 (U.S. Environmental Protection Agency Permit Number TX4213720101), which approved and implemented post-closure care for the Chromic Acid Pit site. In accordance with an approved post-closure plan, the U.S. Geological Survey is cooperating with the U.S. Army in evaluating hydrogeologic conditions and ground- water quality at the site. One upgradient and two downgradient ground-water monitoring wells were installed adjacent to the chromic acid pit by a private contractor. Quarterly ground-water sampling of these wells by the U.S. Geological Survey began in December 1993. The Chromic Acid Pit site is situated in the Hueco Bolson intermontane valley. The Hueco Bolson is a primary source of ground water in the El Paso area. City of El Paso and U.S. Army water-supply wells are located on all sides of the study area and are completed 600 to more than 1,200 feet below land surface. The ground-water level in the area of the Chromic Acid Pit site has declined about 25 feet from 1982 to 1993. Depth to water at the Chromic Acid Pit site in September 1994 was about 284 feet below land surface; ground-water flow is to the southeast. Ground-water samples collected from monitoring wells at the Chromic Acid Pit site contained dissolved-solids concentrations of 442 to 564 milligrams per liter. Nitrate as nitrogen concentrations ranged from 2.1 to 2.7 milligrams per liter; nitrite plus nitrate as nitrogen concentrations ranged from 2.3 to 3.0 milligrams per liter. Nitrate concentrations are abnormally high in the Old Mesa well field located about 5,000 feet southwest of the Chromic Acid Pit site. Volatile and semivolatile organic compounds in water samples were analyzed for the first sampling round; no confirmed volatile or semivolatile organic compounds were detected above the laboratory reporting limits. Total chromium concentrations ranged from 0.0099 to 0.092 milligram per liter; dissolved chromium concentrations ranged from 0.0068 to 0.0094 milligram per liter. Overall, water-quality characteristics in water from the chromic acid pit ground-water monitoring wells are similar to those in the surrounding area. Detected chemical concentrations in water from the chromic acid pit monitoring wells during the four sampling periods were below U.S. Environmental Protection Agency-established maximum contaminant levels for public drinking water supplies. Statistical analyses were performed on 39 of the chemical constituents analyzed for in ground water from the chromic acid pit monitoring wells. Concentrations of chloride and fluoride were significantly less in water from the downgradient wells than in water from the upgradient well, whereas concentrations of nitrate as nitrogen, nitrite plus nitrate as nitrogen, and dissolved solids were significantly greater in water from the downgradient wells than in water from the upgradient well. Concentrations of nitrate as nitrogen were significantly different in water from the two downgradient wells. Differences detected through statistical analysis of chemical constituents of water in the chromic acid pit monitoring wells did not appear to indicate a release of hazardous chemicals from the chromic acid pit. There was no indication of ground-water contamination in either downgradient well.

A fungal endophyte helps plants to tolerate root herbivory through changes in gibberellin and jasmonate signaling.

PubMed

Cosme, Marco; Lu, Jing; Erb, Matthias; Stout, Michael Joseph; Franken, Philipp; Wurst, Susanne

2016-08-01

Plant-microbe mutualisms can improve plant defense, but the impact of root endophytes on below-ground herbivore interactions remains unknown. We investigated the effects of the root endophyte Piriformospora indica on interactions between rice (Oryza sativa) plants and its root herbivore rice water weevil (RWW; Lissorhoptrus oryzophilus), and how plant jasmonic acid (JA) and GA regulate this tripartite interaction. Glasshouse experiments with wild-type rice and coi1-18 and Eui1-OX mutants combined with nutrient, jasmonate and gene expression analyses were used to test: whether RWW adult herbivory above ground influences subsequent damage caused by larval herbivory below ground; whether P. indica protects plants against RWW; and whether GA and JA signaling mediate these interactions. The endophyte induced plant tolerance to root herbivory. RWW adults and larvae acted synergistically via JA signaling to reduce root growth, while endophyte-elicited GA biosynthesis suppressed the herbivore-induced JA in roots and recovered plant growth. Our study shows for the first time the impact of a root endophyte on plant defense against below-ground herbivores, adds to growing evidence that induced tolerance may be an important root defense, and implicates GA as a signal component of inducible plant tolerance against biotic stress. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Refueling Strategies for a Team of Cooperating AUVs

DTIC Science & Technology

2011-01-01

manager, and thus the constraint a centrally managed underwater network imposes on the mission. Task management utilizing Robust Decentralized Task ...the computational complexity. A bid based approach to task management has also been studied as a possible means of decentralization of group task ...currently performing another task . In [18], ground robots perform distributed task allocation using the ASyMTRy-D algorithm, which is based on CNP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halliwell, Stephen

Radioactive waste materials, including Transuranic (TRU) wastes from laboratories have been stored below ground in large containments at a number of sites in the US DOE Complex, and at nuclear sites in Europe. These containments are generally referred to as caissons or shafts. The containments are in a range of sizes and depths below grade. The caissons at the DOE's Hanford site are cylindrical, of the order of 2,500 mm in diameter, 3,050 mm in height and are buried about 6,000 mm below grade. One type of caisson is made out of corrugated pipe, whereas others are made of concretemore » with standard re-bar. However, the larger shafts in the UK are of the order of 4,600 mm in diameter, 53,500 mm deep, and 12,000 below grade. This paper describes the R and D work and testing activities performed to date to evaluate the concept of in-ground size reduction and stabilization of the contents of large containments similar to those at Hanford. In practice, the height of the Test Facility provided for a test cell that was approximately 22' deep. That prevented a 'full scale mockup' test in the sense that the Hanford Caisson configuration would be an identical replication. Therefore, the project was conducted in two phases. The first phase tested a simulated Caisson with surrogate contents, and part of a Chute section, and the second phase tested a full chute section. These tests were performed at VJ Technologies Test Facility located in East Haven, CT, as part of the Proof of Design Concept program for studying the feasibility of an in-situ grout/grind/mix/stabilize technology for the remediation of four caissons at the 618-11 Burial Ground at US Department of Energy Hanford Site. The test site was constructed such that multiple testing areas were provided for the evaluation of various tools, equipment and procedures under conditions that simulated the Hanford site, with representative soils and layout dimensions. (authors)« less

Response of shoal grass, Halodule wrightii, to extreme winter conditions in the Lower Laguna Madre, Texas

USGS Publications Warehouse

Hicks, D.W.; Onuf, C.P.; Tunnell, J.W.

1998-01-01

Effects of a severe freeze on the shoal grass, Halodule wrightii, were documented through analysis of temporal and spatial trends in below-ground biomass. The coincidence of the second lowest temperature (-10.6??C) in 107 years of record, 56 consecutive hours below freezing, high winds and extremely low water levels exposed the Laguna Madre, TX, to the most severe cold stress in over a century. H. wrightii tolerated this extreme freeze event. Annual pre- and post-freeze surveys indicated that below-ground biomass estimated from volume was Unaffected by the freeze event. Nor was there any post-freeze change in biomass among intertidal sites directly exposed to freezing air temperatures relative to subtidal sites which remained submerged during the freezing period.

Quantifying root lateral distribution and turnover using pine trees with a distinct stable carbon isotope signature

Treesearch

Kurt H. Johnsen; Chris A. Maier; Lance W. Kress

2005-01-01

In order to help assess spatial competition for below-ground resources, we quantified the effects of fertilization on root biomass quantity and lateral root distribution of midrotation Pinus taeda trees. Open-top chambers exposed trees to ambient or ambient plus 200 µmol mol-1 atmospheric CO2...

Mineral resource potential map of the Vermilion Cliffs-Paria Canyon instant study area, Coconino County, Arizona, and Kane County, Utah

USGS Publications Warehouse

Bush, Alfred L.; Lane, Michael

1982-01-01

Water is perhaps the most significant resource needed in the study area. A number of perennial springs support the few local ranchers and tourist facilities. Some ground water would be available below the plateau, but drilling depths would be more than 2,000 ft (600-700 m).

A Human-Autonomy Teaming Approach for a Flight-Following Task

NASA Technical Reports Server (NTRS)

Brandt, Summer L.; Russell, Ricky; Lachter, Joel; Shively, Robert

2017-01-01

Managing aircraft is becoming more complex with increasingly sophisticated automation responsible for more flight tasks. With this increased complexity, it is becoming more difficult for operators to understand what the automation is doing and why. Human involvement with increasingly autonomous systems must adjust to allow for a more dynamic relationship involving cooperation and teamwork. As part of an ongoing project to develop a framework for human-autonomy teaming (HAT) in aviation, a part-task study was conducted to demonstrate, evaluate and refine proposed critical aspects of HAT. These features were built into an automated recommender system on a ground station available from previous studies. Participants performed a flight-following task once with the original ground station (i.e., No HAT condition) and once with the HAT features enabled (i.e., HAT condition). Behavioral and subjective measures were collected; subjective measures are presented here. Overall, participants preferred the ground station with HAT features enabled compared to the station without the HAT features. Participants reported that the HAT displays and automation were preferred for keeping up with operationally important issues. Additionally, participants reported that the HAT displays and automation provided enough situation awareness to complete the task and reduced workload relative to the No HAT baseline.

Advanced user support programme—TEMPUS IML-2

NASA Astrophysics Data System (ADS)

Diefenbach, A.; Kratz, M.; Uffelmann, D.; Willnecker, R.

1995-05-01

The DLR Microgravity User Support Centre (MUSC) in Cologne has supported microgravity experiments in the field of materials and life sciences since 1979. In the beginning of user support activities, MUSC tasks comprised the basic ground and mission support, whereas present programmes are expanded on, for example, powerful telescience and advanced real time data acquisition capabilities for efficient experiment operation and monitoring. In view of the Space Station era, user support functions will increase further. Additional tasks and growing responsibilities must be covered, e.g. extended science support as well as experiment and facility operations. The user support for TEMPUS IML-2, under contract of the German Space Agency DARA, represents a further step towards the required new-generation of future ground programme. TEMPUS is a new highly sophisticated Spacelab multi-user facility for containerless processing of metallic samples. Electromagnetic levitation technique is applied and various experiment diagnosis tools are offered. Experiments from eight U.S. and German investigator groups have been selected for flight on the second International Microgravity Laboratory Mission IML-2 in 1994. Based on the experience gained in the research programme of the DLR Institute for Space Simulation since 1984, MUSC is performing a comprehensive experiment preparation programme in close collaboration with the investigator teams. Complex laboratory equipment has been built up for technology and experiment preparation development. New experiment techniques have been developed for experiment verification tests. The MUSC programme includes thorough analysis and testing of scientific requirements of every proposed experiment with respect to the facility hard- and software capabilities. In addition, studies on the experiment-specific operation requirements have been performed and suitable telescience scenarios were analysed. The present paper will give a survey of the TEMPUS user support tasks emphasizing the advanced science support activities, which are considered significant for future ground programmes.

Modeling Coupled Landscape Evolution and Soil Organic Carbon Dynamics in Intensively Management Landscapes

NASA Astrophysics Data System (ADS)

Yan, Q.; Kumar, P.

2017-12-01

Soil is the largest reservoir of carbon in the biosphere but in agricultural areas it is going through rapid erosion due disturbance arising from crop harvest, tillage, and tile drainage. Identifying whether the production of soil organic carbon (SOC) from the crops can compensate for the loss due to erosion is critical to ensure our food security and adapt to climate change. In the U.S. Midwest where large areas of land are intensively managed for agriculture practices, predicting soil quantity and quality are critical for maintaining crop yield and other Critical Zone services. This work focuses on modeling the coupled landscape evolutions soil organic carbon dynamics in agricultural fields. It couples landscape evolution, surface water runoff, organic matter transformation, and soil moisture dynamics to understand organic carbon gain and loss due to natural forcing and farming practices, such as fertilizer application and tillage. A distinctive feature of the model is the coupling of surface ad subsurface processes that predicts both surficial changes and transport along with the vertical transport and dynamics. Our results show that landscape evolution and farming practices play dominant roles in soil organic carbon (SOC) dynamics both above- and below-ground. Contrary to the common assumption that a vertical profile of SOC concentration decreases exponentially with depth, we find that in many situations SOC concentration below-ground could be higher than that at the surface. Tillage plays a complex role in organic matter dynamics. On one hand, tillage would accelerate the erosion rate, on the other hand, it would improve carbon storage by burying surface SOC into below ground. Our model consistently reproduces the observed above- and below-ground patterns of SOC in the field sites of Intensively Managed Landscapes Critical Zone Observatory (IMLCZO). This model bridges the gaps between the landscape evolution, below- and above-ground hydrologic cycle, and biogeochemical processes. This study not only helps us understand the coupled carbon-nitrogen cycle, but also serve as an instrument to develop practical approaches for reducing soil erosion and carbon loss when the landscape is affected by human activities.

Nuclear Thermal Propulsion (NTP) Development Activities at the NASA Marshall Space Flight Center - 2006 Accomplishments

NASA Technical Reports Server (NTRS)

Ballard, Richard O.

2007-01-01

In 2005-06, the Prometheus program funded a number of tasks at the NASA-Marshall Space Flight Center (MSFC) to support development of a Nuclear Thermal Propulsion (NTP) system for future manned exploration missions. These tasks include the following: 1. NTP Design Develop Test & Evaluate (DDT&E) Planning 2. NTP Mission & Systems Analysis / Stage Concepts & Engine Requirements 3. NTP Engine System Trade Space Analysis and Studies 4. NTP Engine Ground Test Facility Assessment 5. Non-Nuclear Environmental Simulator (NTREES) 6. Non-Nuclear Materials Fabrication & Evaluation 7. Multi-Physics TCA Modeling. This presentation is a overview of these tasks and their accomplishments

Stimulation of terrestrial ecosystem carbon storage by nitrogen addition: a meta-analysis

PubMed Central

Yue, Kai; Peng, Yan; Peng, Changhui; Yang, Wanqin; Peng, Xin; Wu, Fuzhong

2016-01-01

Elevated nitrogen (N) deposition alters the terrestrial carbon (C) cycle, which is likely to feed back to further climate change. However, how the overall terrestrial ecosystem C pools and fluxes respond to N addition remains unclear. By synthesizing data from multiple terrestrial ecosystems, we quantified the response of C pools and fluxes to experimental N addition using a comprehensive meta-analysis method. Our results showed that N addition significantly stimulated soil total C storage by 5.82% ([2.47%, 9.27%], 95% CI, the same below) and increased the C contents of the above- and below-ground parts of plants by 25.65% [11.07%, 42.12%] and 15.93% [6.80%, 25.85%], respectively. Furthermore, N addition significantly increased aboveground net primary production by 52.38% [40.58%, 65.19%] and litterfall by 14.67% [9.24%, 20.38%] at a global scale. However, the C influx from the plant litter to the soil through litter decomposition and the efflux from the soil due to microbial respiration and soil respiration showed insignificant responses to N addition. Overall, our meta-analysis suggested that N addition will increase soil C storage and plant C in both above- and below-ground parts, indicating that terrestrial ecosystems might act to strengthen as a C sink under increasing N deposition. PMID:26813078

Water Absorption in Galactic Translucent Clouds: Conditions and History of the Gas Derived from Herschel/HIFI PRISMAS Observations

NASA Astrophysics Data System (ADS)

Flagey, N.; Goldsmith, P. F.; Lis, D. C.; Gerin, M.; Neufeld, D.; Sonnentrucker, P.; De Luca, M.; Godard, B.; Goicoechea, J. R.; Monje, R.; Phillips, T. G.

2013-01-01

We present Herschel/HIFI observations of the three ground state transitions of H2O (556, 1669, and 1113 GHz) and H218O (547, 1655, and 1101 GHz)—as well as the first few excited transitions of H2O (987, 752, and 1661 GHz)—toward six high-mass star-forming regions, obtained as part of the PRISMAS (PRobing InterStellar Molecules with Absorption line Studies) Guaranteed Time Key Program. Water vapor associated with the translucent clouds in Galactic arms is detected in absorption along every line of sight in all the ground state transitions. The continuum sources all exhibit broad water features in emission in the excited and ground state transitions. Strong absorption features associated with the source are also observed at all frequencies except 752 GHz. We model the background continuum and line emission to infer the optical depth of each translucent cloud along the lines of sight. We derive the column density of H2O or H218O for the lower energy level of each transition observed. The total column density of water in translucent clouds is usually about a few 1013 cm-2. We find that the abundance of water relative to hydrogen nuclei is 1 × 10-8 in agreement with models for oxygen chemistry in which high cosmic ray ionization rates are assumed. Relative to molecular hydrogen, the abundance of water is remarkably constant through the Galactic plane with X(H2O) =5 × 10-8, which makes water a good traced of H2 in translucent clouds. Observations of the excited transitions of H2O enable us to constrain the abundance of water in excited levels to be at most 15%, implying that the excitation temperature, T ex, in the ground state transitions is below 10 K. Further analysis of the column densities derived from the two ortho ground state transitions indicates that T ex ~= 5 K and that the density n(H2) in the translucent clouds is below 104 cm-3. We derive the water ortho-to-para ratio for each absorption feature along the line of sight and find that most of the clouds show ratios consistent with the value of 3 expected in thermodynamic equilibrium in the high-temperature limit. However, two clouds with large column densities exhibit a ratio that is significantly below 3. This may argue that the history of water molecules includes a cold phase, either when the molecules were formed on cold grains in the well-shielded, low-temperature regions of the clouds, or when they later become at least partially thermalized with the cold gas (~25 K) in those regions; evidently, they have not yet fully thermalized with the warmer (~50 K) translucent portions of the clouds. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Sonic Boom Prediction and Minimization of the Douglas Reference OPT5 Configuration

NASA Technical Reports Server (NTRS)

Siclari, Michael J.

1999-01-01

Conventional CFD methods and grids do not yield adequate resolution of the complex shock flow pattern generated by a real aircraft geometry. As a result, a unique grid topology and supersonic flow solver was developed at Northrop Grumman based on the characteristic behavior of supersonic wave patterns emanating from the aircraft. Using this approach, it was possible to compute flow fields with adequate resolution several body lengths below the aircraft. In this region, three-dimensional effects are diminished and conventional two-dimensional modified linear theory (MLT) can be applied to estimate ground pressure signatures or sonic booms. To accommodate real aircraft geometries and alleviate the burdensome grid generation task, an implicit marching multi-block, multi-grid finite-volume Euler code was developed as the basis for the sonic boom prediction methodology. The Thomas two-dimensional extrapolation method is built into the Euler code so that ground signatures can be obtained quickly and efficiently with minimum computational effort suitable to the aircraft design environment. The loudness levels of these signatures can then be determined using a NASA generated noise code. Since the Euler code is a three-dimensional flow field solver, the complete circumferential region below the aircraft is computed. The extrapolation of all this field data from a cylinder of constant radius leads to the definition of the entire boom corridor occurring directly below and off to the side of the aircraft's flight path yielding an estimate for the entire noise "annoyance" corridor in miles as well as its magnitude. An automated multidisciplinary sonic boom design optimization software system was developed during the latter part of HSR Phase 1. Using this system, it was found that sonic boom signatures could be reduced through optimization of a variety of geometric aircraft parameters. This system uses a gradient based nonlinear optimizer as the driver in conjunction with a computationally efficient Euler CFD solver (NIIM3DSB) for computing the three-dimensional near-field characteristics of the aircraft. The intent of the design system is to identify and optimize geometric design variables that have a beneficial impact on the ground sonic boom. The system uses a simple wave drag data format to specify the aircraft geometry. The geometry is internally enhanced and analytic methods are used to generate marching grids suitable for the multi-block Euler solver. The Thomas extrapolation method is integrated into this system, and hence, the aircraft's centerline ground sonic boom signature is also automatically computed for a specified cruise altitude and yields the parameters necessary to evaluate the design function. The entire design system has been automated since the gradient based optimization software requires many flow analyses in order to obtain the required sensitivity derivatives for each design variable in order to converge on an optimal solution. Hence, once the problem is defined which includes defining the objective function and geometric and aerodynamic constraints, the system will automatically regenerate the perturbed geometry, the necessary grids, the Euler solution, and finally the ground sonic boom signature at the request of the optimizer.

Neuromotor Task Training for Children with Developmental Coordination Disorder: A Controlled Trial

ERIC Educational Resources Information Center

Niemeijer, A. S.; Smits-Engelsman, B. C. M.; Schoemaker, M. M.

2007-01-01

The aim of this study was to evaluate neuromotor task training (NTT), a recently developed child-centred and task-oriented treatment programme for children with developmental coordination disorder (DCD). A treatment and a non-treatment control group of children with DCD were included. Children were selected if they scored below the 15th centile on…

Choose to Use: Scaffolding for Technology Learning Needs in a Project-Based Learning Environment

ERIC Educational Resources Information Center

Weimer, Peggy D.

2017-01-01

Project-based learning is one approach used by teachers to meet the challenge of developing more technologically proficient students. This approach, however, requires students to manage a large number of tasks including the mastery of technology. If a student's perception that their capability to perform a task falls below the task's difficulty,…

Quantifying auditory handicap. A new approach.

PubMed

Jerger, S; Jerger, J

1979-01-01

This report describes a new audiovisual test procedure for the quantification of auditory handicap (QUAH). The QUAH test attempts to recreate in the laboratory a series of everyday listening situations. Individual test items represent psychomotor tasks. Data on 53 normal-hearing listeners described performance as a function of the message-to-competition ratio (MCR). Results indicated that, for further studies, an MCR of 0 dB represents the condition above which the task seemed too easy and below which the task appeared too difficult for normal-hearing subjects. The QUAH approach to the measurement of auditory handicap seems promising as an experimental tool. Further studies are needed to describe the relation of QUAH results (1) to clinical audiologic measures and (2) to more traditional indices of auditory handicap.

Biogeochemical cycling of carbon, nitrogen, and sulfur at the Howland Integrated Forest Study site, Howland, Maine

Treesearch

James W. McLaughlin; Ivan J. Fernandez; Stewart M. Goltz; Lindsey E. Rustad; Larry Zibilske

1996-01-01

The biogeochemistry of C, N, and S was studied for six years at the Howland Integrated Forest Study (HIFS) site by measuring those constituents in major above- and below-ground pools and fluxes. Leaching losses of C from the solum were much less than CO2 efflux, with a mean annual leaching rate of 31.2 kg ha-1 yr

Solid-State Laser Research Report: Energy Transfer in Non-Uniform Codoped Crystals.

DTIC Science & Technology

1988-03-01

mathematical steps reported in this document are contained in the reviewed classified mid-task report P-1970 which is not available to the open...splits the d lvels of the chromium ion such that the "T2 level is considerably higher in energy than the E level. Since the ground-state is A 2 , the E A 2

Taking-On: A Grounded Theory of Addressing Barriers in Task Completion

ERIC Educational Resources Information Center

Austinson, Julie Ann

2011-01-01

This study of taking-on was conducted using classical grounded theory methodology (Glaser, 1978, 1992, 1998, 2001, 2005; Glaser & Strauss, 1967). Classical grounded theory is inductive, empirical, and naturalistic; it does not utilize manipulation or constrained time frames. Classical grounded theory is a systemic research method used to generate…

The role of below-ground competition during early stages of secondary succession: the case of 3-year-old Scots pine (Pinus sylvestris L.) seedlings in an abandoned grassland.

PubMed

Picon-Cochard, Catherine; Coll, Lluis; Balandier, Philippe

2006-06-01

In abandoned or extensively managed grasslands, the mechanisms involved in pioneer tree species success are not fully explained. Resource competition among plants and microclimate modifications have been emphasised as possible mechanisms to explain variation of survivorship and growth. In this study, we evaluated a number of mechanisms that may lead to successful survival and growth of seedlings of a pioneer tree species (Pinus sylvestris) in a grass-dominated grassland. Three-year-old Scots pines were planted in an extensively managed grassland of the French Massif Central and for 2 years were either maintained in bare soil or subjected to aerial and below-ground interactions induced by grass vegetation. Soil temperatures were slightly higher in bare soil than under the grass vegetation, but not to an extent explaining pine growth differences. The tall grass canopy reduced light transmission by 77% at ground level and by 20% in the upper part of Scots pine seedlings. Grass vegetation presence also significantly decreased soil volumetric water content (Hv) and soil nitrate in spring and in summer. In these conditions, the average tree height was reduced by 5% compared to trees grown in bare soil, and plant biomass was reduced by 85%. Scots pine intrinsic water-use efficiency (A/g), measured by leaf gas-exchange, increased when Hv decreased owing to a rapid decline of stomatal conductance (g). This result was also confirmed by delta 13C analyses of needles. A summer 15N labelling of seedlings and grass vegetation confirmed the higher NO3 capture capacity of grass vegetation in comparison with Scots pine seedlings. Our results provide evidence that the seedlings' success was linked to tolerance of below-ground resource depletion (particularly water) induced by grass vegetation based on morphological and physiological plasticity as well as to resource conservation.

Aldicarb-pesticide contamination of ground water in eastern Suffolk County, Long Island, New York

USGS Publications Warehouse

Soren, Julian; Stelz, W.G.

1984-01-01

Aldicarb, a toxic oxime-carbamate pesticide that was believed incapable of reaching ground water, was used in potato-farming areas of eastern Suffolk County, New York during 1975-80. In 1979, aldicarb was found in substantial concentrations in ground water throughout the area. The New York State Department of Health set a limit of 7 micrograms per liter for aldicarb in drinking water. Extensive ground-water sampling into 1980 showed widespread contamination ranging from small amounts to as much as 515 micrograms per liter. In 1980, the U.S. Environmental Protection Agency banned the use of aldicarb on Long Island at the manufacturer 's request. A 1982 sampling study found aldicarb to have penetrated to about 40 feet below the water table in concentrations ranging from below detection limit to 239 micrograms per liter. Despite reputed toxicity, no instance of aldicarb poisoning on Long Island has been documented. The excessive aldicarb concentrations in the ground water of eastern Long Island may persist for decades; the duration has not been precisely determined and remains under investigation. (USGS)

Ground-Water Levels and Soil Characteristics in a Forested Typic Glossaqualf

Treesearch

Peter L. Lorio

1977-01-01

The presence of impermeable layers can affect the development of a soil and its water regime. In a forested Typic Glossaqualf in southwest Louisiana, moisture, density, and piezometer measurements revealed an impermeable layer of soil between about 1.8 and 2.8 m below the surface. A high proportion of very fine sand and development of platy structure appeared related...

Neutron spectroscopic study of crystal field excitations in Tb 2Ti 2O 7 and Tb 2Sn 2O 7

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, J.; Fritsch, Katharina; Hao, Z.

2014-04-01

We present time-of-flight inelastic neutron scattering measurements at low temperature on powder samples of the magnetic pyrochlore oxides Tb 2Ti 2O 7 and Tb 2Sn 2O 7. These two materials possess related, but different ground states, with Tb 2Sn 2O 7 displaying "soft" spin ice order below T N approx 0.87 K, while Tb 2Ti 2O 7 enters a hybrid, glassy-spin ice state below T g approx 0.2 K. Our neutron measurements, performed at T = 1.5 K and 30 K, probe the crystal field states associated with the J = 6 states of Tb 3+ within the appropriate Fd3-barmmore » pyrochlore environment. These crystal field states determine the size and anisotropy of the Tb 3+ magnetic moment in each material's ground state, information that is an essential starting point for any description of the low temperature phase behavior and spin dynamics in Tb 2Ti 2O 7 and Tb 2Sn 2O 7. While these two materials have much in common, the cubic stanate lattice is expanded compared to the cubic titanate lattice. As our measurements show, this translates into a factor of approx 2 increase in the crystal field bandwidth of the 2J +1 = 13 states in Tb 2Ti 2O 7 compared with Tb 2Sn 2O 7. Our results are consistent with previous measurements on crystal field states in Tb 2Sn 2O 7, wherein the ground state doublet corresponds primarily to mJ = {vert_bar}+-5> and the first excited state doublet to mJ = {vert_bar}+-4>. In contrast, our results on Tb 2Ti 2O 7 differ markedly from earlier studies, showing that the ground state doublet corresponds to a significant mixture of mJ = {vert_bar}+-5>, mJ = {vert_bar}+-4> and mJ = {vert_bar}+-2>, while the first excited state doublet corresponds to a mixture of mJ = {vert_bar}+-4>, mJ = {vert_bar}+-5> and mJ = {vert_bar}+-1>. We discuss these results in the context of proposed mechanisms for the failure of Tb 2Ti 2O 7 to develop conventional long range order down to 50 mK.« less

Using data from the Microsoft Kinect 2 to determine postural stability in healthy subjects: A feasibility trial.

PubMed

Dehbandi, Behdad; Barachant, Alexandre; Smeragliuolo, Anna H; Long, John Davis; Bumanlag, Silverio Joseph; He, Victor; Lampe, Anna; Putrino, David

2017-01-01

The objective of this study was to determine whether kinematic data collected by the Microsoft Kinect 2 (MK2) could be used to quantify postural stability in healthy subjects. Twelve subjects were recruited for the project, and were instructed to perform a sequence of simple postural stability tasks. The movement sequence was performed as subjects were seated on top of a force platform, and the MK2 was positioned in front of them. This sequence of tasks was performed by each subject under three different postural conditions: "both feet on the ground" (1), "One foot off the ground" (2), and "both feet off the ground" (3). We compared force platform and MK2 data to quantify the degree to which the MK2 was returning reliable data across subjects. We then applied a novel machine-learning paradigm to the MK2 data in order to determine the extent to which data from the MK2 could be used to reliably classify different postural conditions. Our initial comparison of force plate and MK2 data showed a strong agreement between the two devices, with strong Pearson correlations between the trunk centroids "Spine_Mid" (0.85 ± 0.06), "Neck" (0.86 ± 0.07) and "Head" (0.87 ± 0.07), and the center of pressure centroid inferred by the force platform. Mean accuracy for the machine learning classifier from MK2 was 97.0%, with a specific classification accuracy breakdown of 90.9%, 100%, and 100% for conditions 1 through 3, respectively. Mean accuracy for the machine learning classifier derived from the force platform data was lower at 84.4%. We conclude that data from the MK2 has sufficient information content to allow us to classify sequences of tasks being performed under different levels of postural stability. Future studies will focus on validating this protocol on large populations of individuals with actual balance impairments in order to create a toolkit that is clinically validated and available to the medical community.

Drought and root herbivory interact to alter the response of above-ground parasitoids to aphid infested plants and associated plant volatile signals.

PubMed

Tariq, Muhammad; Wright, Denis J; Bruce, Toby J A; Staley, Joanna T

2013-01-01

Multitrophic interactions are likely to be altered by climate change but there is little empirical evidence relating the responses of herbivores and parasitoids to abiotic factors. Here we investigated the effects of drought on an above/below-ground system comprising a generalist and a specialist aphid species (foliar herbivores), their parasitoids, and a dipteran species (root herbivore).We tested the hypotheses that: (1) high levels of drought stress and below-ground herbivory interact to reduce the performance of parasitoids developing in aphids; (2) drought stress and root herbivory change the profile of volatile organic chemicals (VOCs) emitted by the host plant; (3) parasitoids avoid ovipositing in aphids feeding on plants under drought stress and root herbivory. We examined the effect of drought, with and without root herbivory, on the olfactory response of parasitoids (preference), plant volatile emissions, parasitism success (performance), and the effect of drought on root herbivory. Under drought, percentage parasitism of aphids was reduced by about 40-55% compared with well watered plants. There was a significant interaction between drought and root herbivory on the efficacy of the two parasitoid species, drought stress partially reversing the negative effect of root herbivory on percent parasitism. In the absence of drought, root herbivory significantly reduced the performance (e.g. fecundity) of both parasitoid species developing in foliar herbivores. Plant emissions of VOCs were reduced by drought and root herbivores, and in olfactometer experiments parasitoids preferred the odour from well-watered plants compared with other treatments. The present work demonstrates that drought stress can change the outcome of interactions between herbivores feeding above- and below-ground and their parasitoids, mediated by changes in the chemical signals from plants to parasitoids. This provides a new insight into how the structure of terrestrial communities may be affected by drought.

29. ISLAND PLANT: INTERIOR VIEW LOOKING SOUTHWEST ON GROUND FLOOR ...

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

29. ISLAND PLANT: INTERIOR VIEW LOOKING SOUTHWEST ON GROUND FLOOR - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

Ground-water conditions and studies in Georgia, 2001

USGS Publications Warehouse

Leeth, David C.; Clarke, John S.; Craigg, Steven D.; Wipperfurth, Caryl J.

2003-01-01

The U.S. Geological Survey (USGS) collects ground-water data and conducts studies to monitor hydrologic conditions, to better define ground-water resources, and address problems related to water supply and water quality. Data collected as part of ground-water studies include geologic, geophysical, hydraulic property, water level, and water quality. A ground-water-level network has been established throughout most of the State of Georgia, and ground-water-quality networks have been established in the cities of Albany, Savannah, and Brunswick and in Camden County, Georgia. Ground-water levels are monitored continuously in a network of wells completed in major aquifers of the State. This network includes 17 wells in the surficial aquifer, 12 wells in the upper and lower Brunswick aquifers, 73 wells in the Upper Floridan aquifer, 10 wells in the Lower Floridan aquifer and underlying units, 12 wells in the Claiborne aquifer, 1 well in the Gordon aquifer, 11 wells in the Clayton aquifer, 11 wells in the Cretaceous aquifer system, 2 wells in Paleozoic-rock aquifers, and 7 wells in crystalline-rock aquifers. In this report, data from these 156 wells were evaluated to determine whether mean-annual ground-water levels were within, below, or above the normal range during 2001, based on summary statistics for the period of record. Information from these summaries indicates that water levels during 2001 were below normal in almost all aquifers monitored, largely reflecting climatic effects from drought and pumping. In addition, water-level hydrographs for selected wells indicate that water levels have declined during the past 5 years (since 1997) in almost all aquifers monitored, with water levels in some wells falling below historical lows. In addition to continuous water-level data, periodic measurements taken in 52 wells in the Camden County-Charlton County area, and 65 wells in the city of Albany-Dougherty County area were used to construct potentiometric-surface maps for the Upper Floridan aquifer. Ground-water quality in the Upper Floridan aquifer is monitored in the cities of Albany, Savannah, and Brunswick and in Camden County; and monitored in the Lower Floridan aquifer in the Savannah and Brunswick areas. In the Albany area since 1998, nitrate concentrations in the Upper Floridan aquifer have increased in 4 of the 11 wells monitored, and in 1 well, concentrations were above the U.S. Environmental Protection Agency's (USEPA) 10 milligrams per liter (mg/L) drinking-water standard. In the Savannah area, chloride concentration in water from four wells in the Upper Floridan aquifer showed no appreciable change during 2001, remaining within the USEPA 250 mg/L drinking-water standard; in seven wells completed in the Lower Floridan aquifer and in underlying zones, the chloride concentration remained above the drinking-water standard, with one well showing an increase over previous years. In the Brunswick area, water samples from 66 wells completed in the Upper or Lower Floridan aquifers were collected during June 2001 and analyzed for chloride. A map showing chloride concentrations in the Upper Floridan aquifer during June 2001 indicates that concentrations remained above USEPA drinking-water standards across a 2-square-mile area. In the north Brunswick area, chloride concentrations in the Upper Floridan aquifer continued to increase, whereas in the south Brunswick area, concentrations continued to decrease. In the Camden County area, chloride concentrations in six wells completed in the Upper Floridan aquifer remained within drinking-water standards. With the exception of one well, concentrations remained the same and were below 40 mg/L. In one well, concentrations showed a sharp decline during 2001, but remained above 130 mg/L. Ongoing studies during 2001 include evaluation of agricultural chemicals in shallow ground water in southwestern Georgia; evaluation of saltwater intrusion and water-level and water-quality m

The Contribution of Microarthropods to Aboveground Food Webs: A Review and Model of Belowground Transfer in a Coniferous Forest

Treesearch

John M. Johnston

1999-01-01

Although below ground food webs have received much attention, studies concerning microarthropods in nondetrital food webs are scarce. because adult oribatid mites often number between 250.000-500,000/ m2 in coniferous forests, microarthropods are a potential food resource for macroarthropod and vertebrate predators of the forest floor. Although...

Spontaneous magnetization-induced phonons stability in γ‧-Fe4N crystalline alloys and high-pressure new phase

NASA Astrophysics Data System (ADS)

Cheng, Tai-min; Yu, Guo-liang; Su, Yong; Zhu, Lin; Li, Lin

2018-04-01

The stability of lattice dynamics and the magnetism of the ordered γ‧-Fe4N crystalline alloy at high pressures were studied by first-principle calculations based on density-functional theory. The dynamical stable new phase P2/m-Fe4N at high pressures was found by conducting the softening phenomenon at the point M (0.5 0.5 0) of the acoustic phonon at 10 GPa in the γ‧-Fe4N via soft-mode phase transition theory. Compared to the phonon spectrum of γ‧-Fe4N without considering electronic spin polarization, the ground-state lattice dynamical stability of the ferromagnetic phase γ‧-Fe4N is induced by the spontaneous magnetization at pressures below 1 GPa. However, P2/m-Fe4N is more thermodynamically stable than γ‧-phase at pressures below 1 GPa, and the magnetic moments of the two phases are almost the same. The ground-state structure of P2/m phase is more stable than that of γ‧-phase in the pressure range from 2.9 to 19 GPa. The magnetic moments of the two phases are almost the same in the pressure range from 20 to 214 GPa, but the ground-state structure of γ‧-phase is more stable than that of P2/m phase in the pressure range from 143.8 to 214 GPa. On the contrary, the ground-state structure of P2/m phase is more stable when the pressure is above 214 GPa. In the pressure range from 214 to 300 GPa, the magnetic moment of P2/m phase is lower than that of γ‧-phase, and the magnetic moments of the two phase tend to be consistent when the pressure exceeds 300 GPa.

Perchlorate as a Ground-Water Tracer Along the Lower Colorado River

NASA Astrophysics Data System (ADS)

Justet, L.; Lico, M. S.

2008-12-01

Anthropogenic perchlorate was first observed in the lower Colorado River (NV and AZ) in 1997. The perchlorate source was traced upstream from Hoover Dam and Lake Mead to Las Vegas Wash. Perchlorate migrated through the local surface- and ground-water systems to the Wash from nearby manufacturing facilities in Henderson, NV, which had been operating since the 1940s. The Nevada Division of Environmental Protection (NDEP) began monitoring perchlorate in the lower Colorado River at Willow Beach, located about 18 km south of the Dam, in 1997. A 3 μg/L reduction was observed at Willow Beach in 2003-2004, coincident with remediation at the Henderson site in 1999-2004. This observed decrease indicates that the effects of remediation rapidly propagated through the surface-water system below the Dam. In July 2008 water samples were collected and analyzed for perchlorate from eight springs along the lower Colorado River below Hoover Dam, from a discharge tunnel in the country rock at Hoover Dam, and from Lake Mead (above and below the thermocline). Lake Mead water collected above the thermocline east of Sentinel Island contained 3.9 μg/L perchlorate, while water below the thermocline contained 1.8 μg/L. Perchlorate concentrations were lower than the 2 to 4 μg/L quantitation limit for the six springs located more than 2 km south of the Dam. Samples from Pupfish Springs, about 0.9 km south of the Dam, contained 6.4-6.8 μg/L perchlorate. Water collected from the discharge tunnel in the Dam contained 8.2 μg/L perchlorate. Perchlorate concentrations observed at Pupfish Springs and the discharge tunnel in the Dam in 2008 are similar to those reported downstream at Willow Beach prior to 2003-2004 by NDEP indicating that the ground water travel time from the Dam to Pupfish Springs is between 4 and 70 years and the maximum flow velocities are between about 13-200 m/y. These rapid velocity estimates suggest that faults and fractures in the area are an important control on discharge points in the vicinity of the Dam. The presence of perchlorate at two sites and absence or background concentrations at the other sites indicates the presence of multiple flow paths between the perchlorate source and the springs near the Dam or that the flow paths are more complex than previously thought.

Agricultural peat lands; towards a greenhouse gas sink - a synthesis of a Dutch landscape study

NASA Astrophysics Data System (ADS)

Schrier-Uijl, A. P.; Kroon, P. S.; Hendriks, D. M. D.; Hensen, A.; Van Huissteden, J. C.; Leffelaar, P. A.; Berendse, F.; Veenendaal, E. M.

2013-06-01

It is generally known that managed, drained peatlands act as carbon sources. In this study we examined how mitigation through the reduction of management and through rewetting may affect the greenhouse gas (GHG) emission and the carbon balance of intensively managed, drained, agricultural peatlands. Carbon and GHG balances were determined for three peatlands in the western part of the Netherlands from 2005 to 2008 by considering spatial and temporal variability of emissions (CO2, CH4 and N2O). One area (Oukoop) is an intensively managed grass-on-peatland, including a dairy farm, with the ground water level at an average annual depth of 0.55 m below the soil surface. The second area (Stein) is an extensively managed grass-on-peatland, formerly intensively managed, with a dynamic ground water level at an average annual depth of 0.45 m below the soil surface. The third area is an (since 1998) rewetted former agricultural peatland (Horstermeer), close to Oukoop and Stein, with the average annual ground water level at a depth of 0.2 m below the soil surface. During the measurement campaigns we found that both agriculturally managed sites acted as carbon and GHG sources but the rewetted agricultural peatland acted as a carbon and GHG sink. The terrestrial GHG source strength was 1.4 kg CO2-eq m-2 yr-1 for the intensively managed area and 1.0 kg CO2-eq m-2 yr-1 for the extensively managed area; the unmanaged area acted as a GHG sink of 0.7 kg CO2-eq m-2 yr-1. Water bodies contributed significantly to the terrestrial GHG balance because of a high release of CH4 and the loss of DOC only played a minor role. Adding the farm-based CO2 and CH4 emissions increased the source strength for the managed sites to 2.7 kg CO2-eq m-2 yr-1 for Oukoop and 2.1 kg CO2-eq m-2 yr-1 for Stein. Shifting from intensively managed to extensively managed grass-on-peat reduced GHG emissions mainly because N2O emission and farm-based CH4 emissions decreased. Overall, this study suggests that managed peatlands are large sources of GHG and carbon, but, if appropriate measures are taken they can be turned back into GHG and carbon sinks within 15 yr of abandonment and rewetting.

Arctic ecosystem functional zones: identification and quantification using an above and below ground monitoring strategy

NASA Astrophysics Data System (ADS)

Hubbard, Susan S.; Ajo-Franklin, Jonathan B.; Dafflon, Baptiste; Dou, Shan; Kneafsey, Tim J.; Peterson, John E.; Tas, Neslihan; Torn, Margaret S.; Phuong Tran, Anh; Ulrich, Craig; Wainwright, Haruko; Wu, Yuxin; Wullschleger, Stan

2015-04-01

Although accurate prediction of ecosystem feedbacks to climate requires characterization of the properties that influence terrestrial carbon cycling, performing such characterization is challenging due to the disparity of scales involved. This is particularly true in vulnerable Arctic ecosystems, where microbial activities leading to the production of greenhouse gasses are a function of small-scale hydrological, geochemical, and thermal conditions influenced by geomorphology and seasonal dynamics. As part of the DOE Next-Generation Ecosystem Experiment (NGEE-Arctic), we are advancing two approaches to improve the characterization of complex Arctic ecosystems, with an initial application to an ice-wedge polygon dominated tundra site near Barrow, AK, USA. The first advance focuses on developing a new strategy to jointly monitor above- and below- ground properties critical for carbon cycling in the tundra. The strategy includes co-characterization of properties within the three critical ecosystem compartments: land surface (vegetation, water inundation, snow thickness, and geomorphology); active layer (peat thickness, soil moisture, soil texture, hydraulic conductivity, soil temperature, and geochemistry); and permafrost (mineral soil and ice content, nature, and distribution). Using a nested sampling strategy, a wide range of measurements have been collected at the study site over the past three years, including: above-ground imagery (LiDAR, visible, near infrared, NDVI) from various platforms, surface geophysical datasets (electrical, electromagnetic, ground penetrating radar, seismic), and point measurements (such as CO2 and methane fluxes, soil properties, microbial community composition). A subset of the coincident datasets is autonomously collected daily. Laboratory experiments and new inversion approaches are used to improve interpretation of the field geophysical datasets in terms of ecosystem properties. The new strategy has significantly advanced our ability to characterize and monitor ecosystem functioning - within and across permafrost, active layer and land-surface compartments and as a function of geomorphology and seasonal dynamics (thaw, growing season, freeze-up, and winter seasons). The second construct uses statistical approaches with the rich datasets to identify Arctic functional zones. Functional zones are regions in the landscape that have unique assemblages of above- and below-ground properties relevant to ecosystem functioning. Results demonstrate the strong co-variation of above and below ground properties in this Arctic ecosystem, particularly highlighting the critical influence of soil moisture on vegetation dynamics and redox-based active-layer biogeochemistry important for carbon cycling. The results also indicate that polygon types (low centered, high centered) have more power to explain the variations in properties than polygon features (trough, rim, center). This finding allows delineation of functional zones through grouping contiguous, similar types of polygons using remote sensing and surface geophysical datasets. Applied to the tundra NGEE study site, the functional zone approach permitted aggregation of critical properties associated with ~1350 polygons and their individual features, which vary over centimeter-to-meter length scales, into a few functional zones having suites of co-varying properties that were tractably defined over ~hundred meter length scales. The developed above-and-below ground monitoring strategy and functional zone approach are proving to be extremely valuable for gaining new insights about a complex Arctic ecosystem and for characterizing the system properties at high resolution and yet with spatial extents relevant for informing models focused on simulating ecosystem-climate feedbacks.

BigBOSS: The Ground-Based Stage IV BAO Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlegel, David; Bebek, Chris; Heetderks, Henry

2009-04-01

The BigBOSS experiment is a proposed DOE-NSF Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with an all-sky galaxy redshift survey. The project is designed to unlock the mystery of dark energy using existing ground-based facilities operated by NOAO. A new 4000-fiber R=5000 spectrograph covering a 3-degree diameter field will measure BAO and redshift space distortions in the distribution of galaxies and hydrogen gas spanning redshifts from 0.2< z< 3.5. The Dark Energy Task Force figure of merit (DETF FoM) for this experiment is expected to be equal to that ofmore » a JDEM mission for BAO with the lower risk and cost typical of a ground-based experiment.« less

Status update of the BWR cask simulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lindgren, Eric R.; Durbin, Samuel G.

2015-09-01

The performance of commercial nuclear spent fuel dry storage casks are typically evaluated through detailed numerical analysis of the system's thermal performance. These modeling efforts are performed by the vendor to demonstrate the performance and regulatory compliance and are independently verified by the Nuclear Regulatory Commission (NRC). Carefully measured data sets generated from testing of full sized casks or smaller cask analogs are widely recognized as vital for validating these models. Numerous studies have been previously conducted. Recent advances in dry storage cask designs have moved the storage location from above ground to below ground and significantly increased the maximummore » thermal load allowed in a cask in part by increasing the canister helium pressure. Previous cask performance validation testing did not capture these parameters. The purpose of the investigation described in this report is to produce a data set that can be used to test the validity of the assumptions associated with the calculations presently used to determine steady-state cladding temperatures in modern dry casks. These modern cask designs utilize elevated helium pressure in the sealed canister or are intended for subsurface storage. The BWR cask simulator (BCS) has been designed in detail for both the above ground and below ground venting configurations. The pressure vessel representing the canister has been designed, fabricated, and pressure tested for a maximum allowable pressure (MAWP) rating of 24 bar at 400 C. An existing electrically heated but otherwise prototypic BWR Incoloy-clad test assembly is being deployed inside of a representative storage basket and cylindrical pressure vessel that represents the canister. The symmetric single assembly geometry with well-controlled boundary conditions simplifies interpretation of results. Various configurations of outer concentric ducting will be used to mimic conditions for above and below ground storage configurations of vertical, dry cask systems with canisters. Radial and axial temperature profiles will be measured for a wide range of decay power and helium cask pressures. Of particular interest is the evaluation of the effect of increased helium pressure on heat load and the effect of simulated wind on a simplified below ground vent configuration.« less

[Vegetation biomass distribution characteristics of alpine tundra ecosystem in Changbai Mountains].

PubMed

Wei, Jing; Wu, Gang; Deng, Hongbing

2004-11-01

Climate change is one of the hotspots in global environment concerns, while alpine tundra ecosystem is most sensitive to global climate change. Because of the relatively small area of tundra, researches on alpine tundra ecosystem were much less. Based on the measurement of species biomass, dominant species organ biomass and vegetation biomass, this paper discussed the biomass spatial variation in alpine tundra ecosystem of Changbai Mountains. The results showed that among 43 species investigated, the first five species in biomass were Rhododendron chrysanthum (159.01 kg x hm(-2)), Vaccinium uliginosum var. alpinum (137.52 kg x hm(-2)), Vaccinium uliginosum (134.7 kg x hm(-2)), Dryas octopetala var. asiatica (131.5 kg x hm(-2)) and Salix rotundifolia (128.4 kg x hm(-2)), which were the dominant species in the alpine tundra ecosystem of Changbai Mountains. Along with increasing altitude, the ratio of below-/above-ground biomass and below-ground/total biomass gradually increased, while the vegetation biomass gradually decreased. The vegetation biomass showed a significant correlation with altitude in typical alpine tundra ecosystem of Changbai Mountains, and the average vegetation biomass was 2.21 t x hm(-2). Alpine tundra ecosystem is very important for microclimate regulation, soil improvement, water-holding, soil conservation, nutrient cycling, carbon fixation and oxygen production, and currently, it is the CO2 sink of Changbai Mountains.

THE APPLICATION AND DEVELOPMENT OF APPROPRIATE TOOLS AND TECHNOLOGIES FOR COST-EFFECTIVE CARBON SEQUESTRATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill Stanley; Sandra Brown; Ellen Hawes

2002-09-01

The Nature Conservancy is participating in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research projects is ''Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration''. The objectives of the project are to: (1) improve carbon offset estimates produced in both the planning and implementation phases of projects; (2) build valid and standardized approaches to estimate project carbon benefits at a reasonable cost; and (3) lay the groundwork for implementing cost-effective projects,more » providing new testing ground for biodiversity protection and restoration projects that store additional atmospheric carbon. This Technical Progress Report discusses preliminary results of the six specific tasks that The Nature Conservancy is undertaking to answer research needs while facilitating the development of real projects with measurable greenhouse gas impacts. The specific tasks discussed include: Task 1: carbon inventory advancements; Task 2: advanced videography testing; Task 3: baseline method development; Task 4: third-party technical advisory panel meetings; Task 5: new project feasibility studies; and Task 6: development of new project software screening tool.« less

FAA UAS Center of Excellence task A4: UAS ground collision severity evaluation.

DOT National Transportation Integrated Search

2017-01-01

The UAS Ground Collision Severity Evaluation Final Report documents the UAS platform characteristics related to the severity of UAS ground collision based upon the literature search of over 300 publications from the automotive industry, consumer batt...

Feedbacks between inundation, root production, and shoot growth in a rapidly submerging brackish marsh

USGS Publications Warehouse

Kirwan, Matthew L.; Guntenspergen, Glenn R.

2012-01-01

6.Synthesis. Below-ground responses of marshes to sea level rise are more broadly applicable than above-ground feedbacks because they are consistent among different species and do not depend on the availability of mineral sediment.

The magnetic structure of Co(NCNH)₂ as determined by (spin-polarized) neutron diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobs, Philipp; Houben, Andreas; Senyshyn, Anatoliy

The magnetic structure of Co(NCNH)₂ has been studied by neutron diffraction data below 10 K using the SPODI and DNS instruments at FRM II, Munich. There is an intensity change in the (1 1 0) and (0 2 0) reflections around 4 K, to be attributed to the onset of a magnetic ordering of the Co²⁺ spins. Four different spin orientations have been evaluated on the basis of Rietveld refinements, comprising antiferromagnetic as well as ferromagnetic ordering along all three crystallographic axes. Both residual values and supplementary susceptibility measurements evidence that only a ferromagnetic ordering with all Co²⁺ spins parallelmore » to the c axis is a suitable description of the low-temperature magnetic ground state of Co(NCNH)₂. The deviation of the magnetic moment derived by the Rietveld refinement from the expectancy value may be explained either by an incomplete saturation of the moment at temperatures slightly below the Curie temperature or by a small Jahn–Teller distortion. - Graphical abstract: The magnetic ground state of Co(NCNH)₂ has been clarified by (spin-polarized) neutron diffraction data at low temperatures. Intensity changes below 4 K arise due to the onset of ferromagnetic ordering of the Co²⁺ spins parallel to the c axis, corroborated by various (magnetic) Rietveld refinements. Highlights: • Powderous Co(NCNH)₂ has been subjected to (spin-polarized) neutron diffraction. • Magnetic susceptibility data of Co(NCNH)₂ have been collected. • Below 4 K, the magnetic moments align ferromagnetically with all Co²⁺ spins parallel to the c axis. • The magnetic susceptibility data yield an effective magnetic moment of 4.68 and a Weiss constant of -13(2) K. • The ferromagnetic Rietveld refinement leads to a magnetic moment of 2.6 which is close to the expectancy value of 3.« less

USING DIRECT-PUSH TOOLS TO MAP HYDROSTRATIGRAPHY AND PREDICT MTBE PLUME DIVING

EPA Science Inventory

Conventional wells for monitoring MTBE contamination at underground storage tank sites are screened a few feet above and a few feet below the water table. At some sites, a plume of contamination in ground water may dive below the screen of conventional monitoring wells and escap...

Controls of vegetation structure and net primary production in restored grasslands

USGS Publications Warehouse

Munson, Seth M.; Lauenroth, William K.

2014-01-01

1. Vegetation structure and net primary production (NPP) are fundamental properties of ecosystems. Understanding how restoration practices following disturbance interact with environmental factors to control these properties can provide insight on how ecosystems recover and guide management efforts. 2. We assessed the relative contribution of environmental and restoration factors in controlling vegetation structure, above- and below-ground investment in production across a chronosequence of semiarid Conservation Reserve Program (CRP) fields recovering from dryland wheat cropping relative to undisturbed grassland. Importantly, we determined the role of plant diversity and how seeding either native or introduced perennial grasses influenced the recovery of vegetation properties. 3. Plant basal cover increased with field age and was highest in CRP fields seeded with native perennial grasses. In contrast, fields seeded with introduced perennial grasses had tall-growing plants with relatively low basal cover. These vegetation structural characteristics interacted with precipitation, but not soil characteristics, to influence above-ground NPP (ANPP). Fields enrolled in the CRP program for >7 years supported twice as much ANPP as undisturbed shortgrass steppe in the first wet year of the study, but all CRP fields converged on a common low amount of ANPP in the following dry year and invested less than half as much as the shortgrass steppe in below-ground biomass. 4. ANPP in CRP fields seeded with native perennial grasses for more than 7 years was positively related to species richness, whereas ANPP in CRP fields seeded with introduced perennial grasses were controlled more by dominant species. 5. Synthesis and applications. Seeding with introduced, instead of native, perennial grasses had a strong direct influence on vegetation structure, including species richness, which indirectly affected NPP through time. However, the effects of restoring either native or introduced grasses on NPP were secondary to low water availability. Therefore, restoration strategies that maximize basal cover and below-ground biomass, which promote water acquisition, may lead to high resilience in semiarid and arid regions.

Biodynamic feedback training to assure learning partial load bearing on forearm crutches.

PubMed

Krause, Daniel; Wünnemann, Martin; Erlmann, Andre; Hölzchen, Timo; Mull, Melanie; Olivier, Norbert; Jöllenbeck, Thomas

2007-07-01

To examine how biodynamic feedback training affects the learning of prescribed partial load bearing (200N). Three pre-post experiments. Biomechanics laboratory in a German university. A volunteer sample of 98 uninjured subjects who had not used crutches recently. There were 24 subjects in experiment 1 (mean age, 23.2y); 64 in experiment 2 (mean age, 43.6y); and 10 in experiment 3 (mean age, 40.3y), parallelized by arm force. Video instruction and feedback training: In experiment 1, 2 varied instruction videos and reduced feedback frequency; in experiment 2, varied frequencies of changing tasks (contextual interference); and in experiment 3, feedback training (walking) and transfer (stair tasks). Vertical ground reaction force. Absolute error of practiced tasks was significantly reduced for all samples (P<.050). Varied contextual interference conditions did not significantly affect retention (P=.798) or transfer (P=.897). Positive transfer between tasks was significant in experiment 2 (P<.001) and was contrary to findings in experiment 3 (P=.071). Biodynamic feedback training is applicable for learning prescribed partial load bearing. The frequency of changing tasks is irrelevant. Despite some support for transfer effects, additional practice in climbing and descending stairs might be beneficial.

Roosevelt Hot Springs, Utah FORGE Earthquake Catalog

DOE Data Explorer

Pankow, Kris

2018-03-21

This is the set of earthquake catalogs developed for the Utah FORGE project. These are discussed in the "Utah FORGE Phase 2B Final Topical Report", which can be found on GDR under id: 1038 (See link 'Final Topical Report' in resources below). The details are in section: 'TASK 2B.12: SEISMIC MONITORING PHASE2B FINAL REPORT.' The catalogs are in an Excel file.

Simulation of projected water demand and ground-water levels in the Coffee Sand and Eutaw-McShan aquifers in Union County, Mississippi, 2010 through 2050

USGS Publications Warehouse

Hutson, Susan S.; Strom, E.W.; Burt, D.E.; Mallory, M.J.

2000-01-01

Ground water from the Eutaw-McShan and the Coffee Sand aquifers is the major source of supply for residential, commercial, and industrial purposes in Union County, Mississippi. Unbiased, scientifically sound data and assessments are needed to assist agencies in better understanding and managing available water resources as continuing development and growth places more stress on available resources. The U.S. Geological Survey, in cooperation with the Tennessee Valley Authority, conducted an investigation using water-demand and ground-water models to evaluate the effect of future water demand on groundwater levels. Data collected for the 12 public-supply facilities and the self-supplied commercial and industrial facilities in Union County were used to construct water-demand models. The estimates of water demand to year 2050 were then input to a ground-water model based on the U.S. Geological Survey finite-difference computer code, MODFLOW. Total ground-water withdrawals for Union County in 1998 were estimated as 2.85 million gallons per day (Mgal/d). Of that amount, municipal withdrawals were 2.55 Mgal/d with about 1.50 Mgal/d (59 percent) delivered to residential users. Nonmunicipal withdrawals were 0.296 Mgal/d. About 80 percent (2.27 Mgal/d) of the total ground-water withdrawal is produced from the Eutaw-McShan aquifer and about 13 percent (0.371 Mgal/d) from the Coffee Sand aquifer. Between normal- and high-growth conditions, total water demand could increase from 72 to 131 percent (2.9 Mgal/d in 1998 to 6.7 Mgal/d in year 2050) with municipal demand increasing from 77 to 146 percent (2.6 to 6.4 Mgal/d). Increased pumping to meet the demand for water was simulated to determine the effect on water levels in the Coffee Sand and Eutaw- McShan aquifers. Under baseline-growth conditions, increased water use by year 2050 could result in an additional 65 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 120 feet of maximum drawdown in the Eutaw-McShan aquifer. Under normal-growth conditions, increased water use could result in an additional 65 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 135 feet of maximum drawdown in the Eutaw-McShan aquifer. Under high-growth conditions, increased water use could result in 75 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 190 feet of maximum drawdown in the Eutaw-McShan aquifer. The resulting highgrowth projected water level for the year 2050 at the center of the drawdown cone in the New Albany area is between 450 and 500 feet above the top of the Eutaw-McShan aquifer.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long-term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of earth tempering as a practice and of specific earth-sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermalmore » advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Also contained in the report are reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 29 locations in the United States.« less

Magnetic order and interactions in ferrimagnetic Mn 3 Si 2 Te 6

DOE Office of Scientific and Technical Information (OSTI.GOV)

May, Andrew F.; Liu, Yaohua; Calder, Stuart

2017-05-01

The magnetism in Mn 3Si 2Te 6 has been investigated using thermodynamic measurements, first principles calculations, neutron diffraction and diffuse neutron scattering on single crystals. These data con rm that Mn3Si2Te6 is a ferrimagnet below T C 78 K. The magnetism is anisotropic, with magnetization and neutron diffraction demonstrating that the moments lie within the basal plane of the trigonal structure. The saturation magnetization of 1.6 B/Mn at 5K originates from the different multiplicities of the two antiferromagnetically-aligned Mn sites. First principles calculations reveal antiferromagnetic exchange for the three nearest Mn-Mn pairs, which leads to a competition between the ferrimagneticmore » ground state and three other magnetic configurations. The ferrimagnetic state results from the energy associated with the third-nearest neighbor interaction, and thus long- range interactions are essential for the observed behavior. Di use magnetic scattering is observed around the 002 Bragg reflection at 120 K, which indicates the presence of strong spin correlations well above T C . These are promoted by the competing ground states that result in a relative suppression of T C , and may be associated with a small ferromagnetic component that produces anisotropic magnetism below ≈ 330 K.« less

2015 Space Human Factors Engineering Standing Review Panel

NASA Technical Reports Server (NTRS)

Steinberg, Susan

2015-01-01

The 2015 Space Human Factors Engineering (SHFE) Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on December 2 - 3, 2015. The SRP reviewed the updated research plans for the Risk of Inadequate Design of Human and Automation/Robotic Integration (HARI Risk), the Risk of Inadequate Human-Computer Interaction (HCI Risk), and the Risk of Inadequate Mission, Process and Task Design (MPTask Risk). The SRP also received a status update on the Risk of Incompatible Vehicle/Habitat Design (Hab Risk) and the Risk of Performance Errors Due to Training Deficiencies (Train Risk). The SRP is pleased with the progress and responsiveness of the SHFE team. The presentations were much improved this year. The SRP is also pleased with the human-centered design approach. Below are some of the more extensive comments from the SRP. We have also made comments in each section concerning gaps/tasks in each. The comments below reflect more significant changes that impact more than just one particular section.

Measured density of copper atoms in the ground and metastable states in argon magnetron discharge correlated with the deposition rate

NASA Astrophysics Data System (ADS)

Naghshara, H.; Sobhanian, S.; Khorram, S.; Sadeghi, N.

2011-01-01

In a dc-magnetron discharge with argon feed gas, densities of copper atoms in the ground state Cu(2S1/2) and metastable state Cu*(2D5/2) were measured by the resonance absorption technique, using a commercial hollow cathode lamp as light source. The operating conditions were 0.3-14 µbar argon pressure and 10-200 W magnetron discharge power. The deposition rate of copper in a substrate positioned at 18 cm from the target was also measured with a quartz microbalance. The gas temperature, in the range 300-380 K, was deduced from the emission spectral profile of N2(C 3Πu - B 3Πg) 0-0 band at 337 nm when trace of nitrogen was added to the argon feed gas. The isotope-shifts and hyperfine structures of electronic states of Cu have been taken into account to deduce the emission and absorption line profiles, and hence for the determination of atoms' densities from the measured absorption rates. To prevent error in the evaluation of Cu density, attributed to the line profile distortion by auto-absorption inside the lamp, the lamp current was limited to 5 mA. Density of Cu(2S1/2) atoms and deposition rate both increased with the enhanced magnetron discharge power. But at fixed power, the copper density augmented with argon pressure whereas the deposition rate followed the opposite trend. Whatever the gas pressure, the density of Cu*(2D5/2) metastable atoms remained below the detection limit of 1 × 1010 cm-3 for magnetron discharge powers below 50 W and hence increased much more rapidly than the density of Cu(2S1/2) atoms, over passing this later at some discharge power, whose value decreases with increasing argon pressure. This behaviour is believed to result from the enhancement of plasma density with increasing discharge power and argon pressure, which would increase the excitation rate of copper into metastable states. At fixed pressure, the deposition rate followed the same trend as the total density of copper atoms in the ground and metastable states. Two important conclusions of this work are (i) copper atoms sputtered from the target under ion bombardment are almost all in the ground state Cu(2S1/2) and hence in the plasma volume they can be excited into the metastable states; (ii) all atoms in the long-lived ground and metastable states contribute to the deposition of copper layer on the substrate.

College and University Business Officers: Their Numerical Representation, Tasks, and Training.

ERIC Educational Resources Information Center

Moxley, Linda S.

A review of the higher education business affairs literature provided the data for this report. Five topics are addressed: (1) the major categories of business affairs management positions below that of chief business officer; (2) counts or estimates of the number of people in each major position category; (3) education and experience requirements…

Soil Organic Carbon and Below Ground Biomass: Development of New GLOBE Special Measurements

NASA Technical Reports Server (NTRS)

Levine, Elissa; Haskett, Jonathan

1999-01-01

A scientific consensus is building that changes in the atmospheric concentrations of radiatively active gases are changing the climate (IPCC, 1990). One of these gases CO2 has been increasing in concentration due to additions from anthropogenic sources that are primarily industrial and land use related. The soil contains a very large pool of carbon, estimated at 1550 Gt (Lal 1995) which is larger than the atmospheric and biosphere pools of carbon combined (Greenland, 1995). The flux between the soil and the atmosphere is very large, 60 Pg C/yr (Lal 1997), and is especially important because the soil can act as either a source or a sink for carbon. On any given landscape, as much as 50% of the biomass that provides the major source of carbon can be below ground. In addition, the movement of carbon in and out of the soil is mediated by the living organisms. At present, there is no widespread sampling of soil biomass in any consistent or coordinated manner. Current large scale estimates of soil carbon are limited by the number and widely dispersed nature of the data points available. A measurement of the amount of carbon in the soil would supplement existing carbon data bases as well as provide a benchmark that can be used to determine whether the soil is storing carbon or releasing it to the atmosphere. Information on the below ground biomass would be a valuable addition to our understanding of net primary productivity and standing biomass. The addition of these as special measurements within GLOBE would be unique in terms of areal extent and continuity, and make a real contribution to scientific understanding of carbon dynamics.

Comparison of Relative Humidity obtained from SAPHIR on board Megha-Tropiques and Ground based Microwave Radiometer Profiler over an equatorial station

NASA Astrophysics Data System (ADS)

Renju, Ramachandran Pillai; Uma, K. N.; Krishna Moorthy, K.; Mathew, Nizy; Raju C, Suresh

A comparison has been made between the SAPHIR on board Megha-Tropiques (MT) derived Relative Humidity (RH (%)) with that derived from a ground based multi-frequency Microwave Radiometer Profiler (MRP) observations over an equatorial station Thiruvananthapuram (8.5(°) N and 76.9(°) E) for a one year period. As a first step, the validation of MRP has been made against the radiosonde for two years (2010 and 2011) during the Indian monsoon period July-September. This analysis shows a wet bias below 6 km and dry bias above. The comparison between the MRP and the MT derived RH has been made at five different altitudinal levels (0.75, 2.25, 4.0, 6.25 and 9.2 km range) strictly under clear sky condition. The regression analysis between the two reveals very good correlation (>0.8) in the altitudinal layer of 2.25 to 6.25 km. The differences between the two observations had also been explained interms of percentage of occurrence between MT and the MRP at each altitudinal layer. About 70-80% of the time, the difference in the RH is found to below 10% at first three layer. The RMSE of 2% is observed at almost all the height layers. The differences have been attributed to the different measurement and retrieval techniques involved in the ground based and satellite based measurements. Since MRP frequecy channels are not sensitive to small water vapor variabilities above 6 km, large differences are observed. Radiative Transfer computation for the channels of both MRP and SAPHIR will be carried out to understand the variabilities.

Collection of liquid from below-ground location

DOEpatents

Phillips, Steven J.; Alexander, Robert G.

1995-01-01

A method of retrieving liquid from a below-ground collection area by permitting gravity flow of the liquid from the collection area to a first closed container; monitoring the level of the liquid in the closed container; and after the liquid reaches a given level in the first closed container, transferring the liquid to a second closed container disposed at a location above the first closed container, via a conduit, by introducing into the first closed container a gas which is substantially chemically inert with respect to the liquid, the gas being at a pressure sufficient to propel the liquid from the first closed container to the second closed container.

Mind the Gap: Task Design and Technology in Novice Language Teachers' Practice

ERIC Educational Resources Information Center

Smits, Tom F. H.; Oberhofer, Margret; Colpaert, Jozef

2016-01-01

This paper focuses on the possibilities/challenges for English as a Foreign Language (EFL) teachers designing tasks grounded in Task-Based Language Teaching (TBLT) and taking advantage of the affordances of technology--Interactive WhiteBoards (IWBs). Teachers have been shown to confuse tasks with exercises or activities. The interactive…

Disorder from order among anisotropic next-nearest-neighbor Ising spin chains in SrHo 2O 4

DOE PAGES

Wen, J. -J.; Tian, W.; Garlea, V. O.; ...

2015-02-26

In this study, we describe why Ising spin chains with competing interactions in SrHo 2O 4 segregate into ordered and disordered ensembles at low temperatures (T). Using elastic neutron scattering, magnetization, and specific heat measurements, the two distinct spin chains are inferred to have Néel (↑↓↑↓) and double-Néel (↑↑↓↓) ground states, respectively. Below T N = 0.68(2)K, the Néel chains develop three-dimensional long range order (LRO), which arrests further thermal equilibration of the double-Néel chains so they remain in a disordered incommensurate state for T below T S = 0.52(2)K. SrHo 2O 4 distills an important feature of incommensurate lowmore » dimensional magnetism: kinetically trapped topological defects in a quasi–d–dimensional spin system can preclude order in d + 1 dimensions.« less

Magnetic structure driven ferroelectricity and large magnetoelectric coupling in antiferromagnet Co4Nb2O9

NASA Astrophysics Data System (ADS)

Srivastava, P.; Chaudhary, S.; Maurya, V.; Saha, J.; Kaushik, S. D.; Siruguri, V.; Patnaik, S.

2018-05-01

Synthesis and extensive structural, pyroelectric, magnetic, dielectric and magneto-electric characterizations are reported for polycrystalline Co4Nb2O9 towards unraveling the multiferroic ground state. Magnetic measurements confirm that Co4Nb2O9 becomes an anti-ferromagnet at around 28 K. Associated with the magnetic phase transition, a sharp peak in pyroelectric current indicates the appearance of strong magneto-electric coupling below Neel temperature (TN) along with large coupling constant upto 17.8 μC/m2T. Using temperature oscillation technique, we establish Co4Nb2O9 to be a genuine multiferroic with spontaneous electric polarization in the anti-ferromagnetic state in the absence of magnetic field poling. This is in agreement with our low temperature neutron diffraction studies that show the magnetic structure of Co4Nb2O9 to be that of a non-collinear anti-ferromagnet with ferroelectric ground state.

75 FR 42059 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Giant...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-20

... organic matter within the soil or at the soil-litter interface) or anecic (earthworms that inhabit deep... subsurface organic matter, rather than transporting plant material below ground. Life- history forms aside... organic matter available to the GPE for forage (Veseth 1986b, p. 2; Petition, pp. 10-11). All original...

A PCR-based method for detecting the mycelia of stipitate hydnoid fungi in soil.

PubMed

van der Linde, Sietse; Alexander, Ian; Anderson, Ian C

2008-09-01

To reduce the reliance on sporocarp records for conservation efforts, information on the below-ground distribution of specific fungal species, such as stipitate hydnoid fungi, is required. Species-specific primers were developed within the internal transcribed spacer (ITS1 and ITS2) regions for 12 hydnoid fungal species including Bankera fuligineoalba, Hydnellum aurantiacum, H. caeruleum, H. concrescens, H. ferrugineum, H. peckii, Phellodon confluens, P. melaleucus, P. niger, P. tomentosus, Sarcodon glaucopus and S. squamosus. The specificity of the primer pairs was tested using BLAST searches and PCR amplifications. All primers amplified DNA only of the target species with the exception of those designed for P. melaleucus. In order to assess the ability of the primers to detect DNA from mycelium in soil, DNA extracted from soil samples taken from around solitary H. peckii sporocarps was amplified with the H. peckii primer 1peck and ITS2. H. peckii DNA was detected in 70% of all soil samples and up to 40 cm away from the base of individual sporocarps. The development of these species-specific primers provides a below-ground alternative for monitoring the distribution of these rare fungi.

Ground-water quality beneath solid-waste disposal sites at anchorage, Alaska

USGS Publications Warehouse

Zenone, Chester; Donaldson, D.E.; Grunwaldt, J.J.

1975-01-01

Studies at three solid-waste disposal sites in the Anchorage area suggest that differences in local geohydrologic conditions influence ground-water quality. A leachate was detected in ground water within and beneath two sites where the water table is very near land surface and refuse is deposited either at or below the water table in some parts of the filled areas. No leachate was detected in ground water beneath a third site where waste disposal is well above the local water table.

Test Plan for the Boiling Water Reactor Dry Cask Simulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Durbin, Samuel; Lindgren, Eric R.

The thermal performance of commercial nuclear spent fuel dry storage casks are evaluated through detailed numerical analysis . These modeling efforts are completed by the vendor to demonstrate performance and regulatory compliance. The calculations are then independently verified by the Nuclear Regulatory Commission (NRC). Carefully measured data sets generated from testing of full sized casks or smaller cask analogs are widely recognized as vital for validating these models. Recent advances in dry storage cask designs have significantly increased the maximum thermal load allowed in a cask in part by increasing the efficiency of internal conduction pathways and by increasing themore » internal convection through greater canister helium pressure. These same vertical, canistered cask systems rely on ventilation between the canister and the overpack to convect heat away from the canister to the environment for both above and below-ground configurations. While several testing programs have been previously conducted, these earlier validation attempts did not capture the effects of elevated helium pressures or accurately portray the external convection of above-ground and below-ground canistered dry cask systems. The purpose of the investigation described in this report is to produce a data set that can be used to test the validity of the assumptions associated with the calculations presently used to determine steady-state cladding temperatures in modern vertical, canistered dry cask systems. The BWR cask simulator (BCS) has been designed in detail for both the above-ground and below-ground venting configurations. The pressure vessel representing the canister has been designed, fabricated, and pressure tested for a maximum allowable pressure (MAWP) rating of 24 bar at 400 deg C. An existing electrically heated but otherwise prototypic BWR Incoloy-clad test assembly is being deployed inside of a representative storage basket and cylindrical pressure vessel that represents the canister. The symmetric single assembly geometry with well-controlled boundary conditions simplifies interpretation of results. Various configurations of outer concentric ducting will be used to mimic conditions for above and below-ground storage configurations of vertical, dry cask systems with canisters. Radial and axial temperature profiles will be measured for a wide range of decay power and helium cask pressures. Of particular interest is the evaluation of the effect of increased helium pressure on allowable heat load and the effect of simulated wind on a simplified below ground vent configuration. While incorporating the best available information, this test plan is subject to changes due to improved understanding from modeling or from as-built deviations to designs. As-built conditions and actual procedures will be documented in the final test report.« less

F-14 modeling study

NASA Technical Reports Server (NTRS)

Levison, William H.

1988-01-01

This study explored application of a closed loop pilot/simulator model to the analysis of some simulator fidelity issues. The model was applied to two data bases: (1) a NASA ground based simulation of an air-to-air tracking task in which nonvisual cueing devices were explored, and (2) a ground based and inflight study performed by the Calspan Corporation to explore the effects of simulator delay on attitude tracking performance. The model predicted the major performance trends obtained in both studies. A combined analytical and experimental procedure for exploring simulator fidelity issues is outlined.

Insulating and metallic spin glass in Ni-doped K x Fe 2 - y Se 2 single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryu, Hyejin; Abeykoon, Milinda; Wang, Kefeng

2015-05-01

Here in this paper, we report electron doping effects by Ni in K xFe 2- δ-y Ni ySe 2 (0.06 ≤ y ≤ 1.44) single-crystal alloys. A rich ground-state phase diagram is observed. A small amount of Ni (~4 %) suppressed superconductivity below 1.8 K, inducing insulating spin-glass magnetic ground state for higher Ni content. With further Ni substitution, metallic resistivity is restored. For high Ni concentration in the lattice the unit cell symmetry is high symmetry I4/mmm with no phase separation whereas both I4 / m + I4/mmm space groups were detected in the phase separated crystals when concentrationmore » of Ni< Fe. The absence of superconductivity coincides with the absence of crystalline Fe vacancy order.« less

System architecture for asynchronous multi-processor robotic control system

NASA Technical Reports Server (NTRS)

Steele, Robert D.; Long, Mark; Backes, Paul

1993-01-01

The architecture for the Modular Telerobot Task Execution System (MOTES) as implemented in the Supervisory Telerobotics (STELER) Laboratory is described. MOTES is the software component of the remote site of a local-remote telerobotic system which is being developed for NASA for space applications, in particular Space Station Freedom applications. The system is being developed to provide control and supervised autonomous control to support both space based operation and ground-remote control with time delay. The local-remote architecture places task planning responsibilities at the local site and task execution responsibilities at the remote site. This separation allows the remote site to be designed to optimize task execution capability within a limited computational environment such as is expected in flight systems. The local site task planning system could be placed on the ground where few computational limitations are expected. MOTES is written in the Ada programming language for a multiprocessor environment.

Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests.

PubMed

Clemmensen, Karina E; Finlay, Roger D; Dahlberg, Anders; Stenlid, Jan; Wardle, David A; Lindahl, Björn D

2015-03-01

Boreal forest soils store a major proportion of the global terrestrial carbon (C) and below-ground inputs contribute as much as above-ground plant litter to the total C stored in the soil. A better understanding of the dynamics and drivers of root-associated fungal communities is essential to predict long-term soil C storage and climate feedbacks in northern ecosystems. We used 454-pyrosequencing to identify fungal communities across fine-scaled soil profiles in a 5000 yr fire-driven boreal forest chronosequence, with the aim of pinpointing shifts in fungal community composition that may underlie variation in below-ground C sequestration. In early successional-stage forests, higher abundance of cord-forming ectomycorrhizal fungi (such as Cortinarius and Suillus species) was linked to rapid turnover of mycelial biomass and necromass, efficient nitrogen (N) mobilization and low C sequestration. In late successional-stage forests, cord formers declined, while ericoid mycorrhizal ascomycetes continued to dominate, potentially facilitating long-term humus build-up through production of melanized hyphae that resist decomposition. Our results suggest that cord-forming ectomycorrhizal fungi and ericoid mycorrhizal fungi play opposing roles in below-ground C storage. We postulate that, by affecting turnover and decomposition of fungal tissues, mycorrhizal fungal identity and growth form are critical determinants of C and N sequestration in boreal forests. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Increased Force Variability in Chronic Stroke: Contributions of Force Modulation below 1 Hz

PubMed Central

Lodha, Neha; Misra, Gaurav; Coombes, Stephen A.; Christou, Evangelos A.; Cauraugh, James H.

2013-01-01

Increased force variability constitutes a hallmark of arm disabilities following stroke. Force variability is related to the modulation of force below 1 Hz in healthy young and older adults. However, whether the increased force variability observed post stroke is related to the modulation of force below 1 Hz remains unknown. Thus, the purpose of this study was to compare force modulation below 1 Hz in chronic stroke and age-matched healthy individuals. Both stroke and control individuals (N = 26) performed an isometric grip task to submaximal force levels. Coefficient of variation quantified force variability, and power spectrum density of force quantified force modulation below 1 Hz with a high resolution (0.07 Hz). Analyses indicated that force variability was greater for the stroke group compared with to healthy controls and for the paretic hand compared with the non-paretic hand. Force modulation below 1 Hz differentiated the stroke individuals and healthy controls, as well as the paretic and non-paretic hands. Specifically, stroke individuals (paretic hand) exhibited greater power ∼0.2 Hz (0.07–0.35 Hz) and lesser power ∼0.6 Hz (0.49–0.77 Hz) compared to healthy controls (non-dominant hand). Similarly, the paretic hand exhibited greater power ∼0.2 Hz, and lesser power ∼0.6 Hz than the non-paretic hand. Moreover, variability of force was strongly predicted from the modulation of specific frequencies below 1 Hz (R 2 = 0.80). Together, these findings indicate that the modulation of force below 1 Hz provides significant insight into changes in motor control after stroke. PMID:24386208

Quantification of gait changes in subjects with visual height intolerance when exposed to heights.

PubMed

Schniepp, Roman; Kugler, Günter; Wuehr, Max; Eckl, Maria; Huppert, Doreen; Huth, Sabrina; Pradhan, Cauchy; Jahn, Klaus; Brandt, Thomas

2014-01-01

Visual height intolerance (vHI) manifests as instability at heights with apprehension of losing balance or falling. We investigated contributions of visual feedback and attention on gait performance of subjects with vHI. Sixteen subjects with vHI walked over a gait mat (GAITRite®) on a 15-m-high balcony and at ground-level. Subjects walked at different speeds (slow, preferred, fast), during changes of the visual input (gaze straight/up/down; eyes open/closed), and while doing a cognitive task. An rmANOVA with the factors "height situation" and "gait condition" was performed. Subjects were also asked to estimate the height of the balcony over ground level. The individual estimates were used for correlations with the gait parameters. Study participants walked slower at heights, with reduced cadence and stride length. The double support phases were increased (all p < 0.01), which correlated with the estimated height of the balcony (R (2) = 0.453, p < 0.05). These changes were still present when walking with upward gaze or closure of the eyes. Under the conditions walking and looking down to the floor of the balcony, during dual-task and fast walking, there were no differences between the gait performance on the balcony and at ground-level. The found gait changes are features of a cautious gait control. Internal, cognitive models with anxiety play an important role for vHI; gait was similarly affected when the visual perception of the depth was prevented. Improvement by dual task at heights may be associated by a reduction of the anxiety level. It is conceivable that mental distraction by dual task or increasing the walking speed might be useful recommendations to reduce the imbalance during locomotion in subjects susceptible to vHI.

Geophysical Images of the Shallow Hydrothermal Degassing at Solfatara (Phlegrean Fields, Italy)

NASA Astrophysics Data System (ADS)

Byrdina, S.; Vandemeulebrouck, J.; Cardellini, C.; Chiodini, G.; Legaz, A.; Camerlynck, C.; Lebourg, T.

2014-12-01

We present the results of an electric resistivity tomography (ERT) survey, combined with mappings of diffuse carbon dioxide flux, ground temperature and self-potential (SP) at Solfatara, the most active crater of Phlegrean Fields. Solfatara is characterized by an intense carbon dioxide degassing, fumarole activity, and ground deformation. This ensemble of methods is applied to image the hydrothermal system of Solfatara, to understand the geometry of the fluid circulation, and to define the extension of the hydrothermal plume at a high enough resolution for a quantitative modeling. ERT inversion results show Solfatara as a globally conductive structure, with resistivity in the range 1-200 Ohmm. Broad negative anomaly of self-potential in the inner part of Solfatara with a minimum in the area of Bocca Grande suggests a significant downward flow of condensing liquid water. Comparison between spatial variations of resistivity and gas flux indicates that resistivity changes at depth are related to gas saturation and fluid temperature. These variations delineate two plume structures: a liquid-dominated conductive plume below Fangaia mud-pool and a gas-dominated plume below Bocca Grande fumarole. The geometry of the Fangaia liquid-saturated plume is also imaged by a high resolution 3-D resistivity model. In order to estimate the permeability, we propose a 2-D axis-symmetric numerical model coupling Richards's equation for fluid flow in conditions of partial saturation with the resistivity calculation as function of saturation only. Alternatively, we apply the Dupuit equation to estimate the permeability of the shallow layer. Using these two approaches, we obtain the permeability of the shallow layer below Fangaia which ranges between (2 - 4) 10-14 m 2.

Using ADA Tasks to Simulate Operating Equipment

NASA Technical Reports Server (NTRS)

DeAcetis, Louis A.; Schmidt, Oron; Krishen, Kumar

1990-01-01

A method of simulating equipment using ADA tasks is discussed. Individual units of equipment are coded as concurrently running tasks that monitor and respond to input signals. This technique has been used in a simulation of the space-to-ground Communications and Tracking subsystem of Space Station Freedom.

Using Ada tasks to simulate operating equipment

NASA Technical Reports Server (NTRS)

Deacetis, Louis A.; Schmidt, Oron; Krishen, Kumar

1990-01-01

A method of simulating equipment using Ada tasks is discussed. Individual units of equipment are coded as concurrently running tasks that monitor and respond to input signals. This technique has been used in a simulation of the space-to-ground Communications and Tracking subsystem of Space Station Freedom.

Research on Scheduling Algorithm for Multi-satellite and Point Target Task on Swinging Mode

NASA Astrophysics Data System (ADS)

Wang, M.; Dai, G.; Peng, L.; Song, Z.; Chen, G.

2012-12-01

Nowadays, using satellite in space to observe ground is an important and major method to obtain ground information. With the development of the scientific technology in the field of space, many fields such as military and economic and other areas have more and more requirement of space technology because of the benefits of the satellite's widespread, timeliness and unlimited of area and country. And at the same time, because of the wide use of all kinds of satellites, sensors, repeater satellites and ground receiving stations, ground control system are now facing great challenge. Therefore, how to make the best value of satellite resources so as to make full use of them becomes an important problem of ground control system. Satellite scheduling is to distribute the resource to all tasks without conflict to obtain the scheduling result so as to complete as many tasks as possible to meet user's requirement under considering the condition of the requirement of satellites, sensors and ground receiving stations. Considering the size of the task, we can divide tasks into point task and area task. This paper only considers point targets. In this paper, a description of satellite scheduling problem and a chief introduction of the theory of satellite scheduling are firstly made. We also analyze the restriction of resource and task in scheduling satellites. The input and output flow of scheduling process are also chiefly described in the paper. On the basis of these analyses, we put forward a scheduling model named as multi-variable optimization model for multi-satellite and point target task on swinging mode. In the multi-variable optimization model, the scheduling problem is transformed the parametric optimization problem. The parameter we wish to optimize is the swinging angle of every time-window. In the view of the efficiency and accuracy, some important problems relating the satellite scheduling such as the angle relation between satellites and ground targets, positive and negative swinging angle and the computation of time window are analyzed and discussed. And many strategies to improve the efficiency of this model are also put forward. In order to solve the model, we bring forward the conception of activity sequence map. By using the activity sequence map, the activity choice and the start time of the activity can be divided. We also bring forward three neighborhood operators to search the result space. The front movement remaining time and the back movement remaining time are used to analyze the feasibility to generate solution from neighborhood operators. Lastly, the algorithm to solve the problem and model is put forward based genetic algorithm. Population initialization, crossover operator, mutation operator, individual evaluation, collision decrease operator, select operator and collision elimination operator is designed in the paper. Finally, the scheduling result and the simulation for a practical example on 5 satellites and 100 point targets with swinging mode is given, and the scheduling performances are also analyzed while the swinging angle in 0, 5, 10, 15, 25. It can be shown by the result that the model and the algorithm are more effective than those ones without swinging mode.

Species richness alters spatial nutrient heterogeneity effects on above-ground plant biomass.

PubMed

Xi, Nianxun; Zhang, Chunhui; Bloor, Juliette M G

2017-12-01

Previous studies have suggested that spatial nutrient heterogeneity promotes plant nutrient capture and growth. However, little is known about how spatial nutrient heterogeneity interacts with key community attributes to affect plant community production. We conducted a meta-analysis to investigate how nitrogen heterogeneity effects vary with species richness and plant density. Effect size was calculated using the natural log of the ratio in plant biomass between heterogeneous and homogeneous conditions. Effect sizes were significantly above zero, reflecting positive effects of spatial nutrient heterogeneity on community production. However, species richness decreased the magnitude of heterogeneity effects on above-ground biomass. The magnitude of heterogeneity effects on below-ground biomass did not vary with species richness. Moreover, we detected no modification in heterogeneity effects with plant density. Our results highlight the importance of species richness for ecosystem function. Asynchrony between above- and below-ground responses to spatial nutrient heterogeneity and species richness could have significant implications for biotic interactions and biogeochemical cycling in the long term. © 2017 The Author(s).

Comparison of GOME-2/Metop total column water vapour with ground-based and in situ measurements

NASA Astrophysics Data System (ADS)

Kalakoski, N.; Kujanpää, J.; Sofieva, V.; Tamminen, J.; Grossi, M.; Valks, P.

2014-12-01

Total column water vapour product from the Global Ozone Monitoring Experiment-2 on board Metop-A and Metop-B satellites (GOME-2/Metop-A and GOME-2/Metop-B) produced by the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF) is compared with co-located radiosonde and Global Positioning System (GPS) observations. The comparisons are performed using recently reprocessed data by the GOME Data Processor (GDP) version 4.7. The comparisons are performed for the period of January 2007-July 2013 (GOME-2A) and from December 2012 to July 2013 (GOME-2B). Radiosonde data are from the Integrated Global Radiosonde Archive (IGRA) maintained by National Climatic Data Center (NCDC) and screened for soundings with incomplete tropospheric column. Ground-based GPS observations from COSMIC/SuomiNet network are used as the second independent data source. Good general agreement between GOME-2 and the ground-based observations is found. The median relative difference of GOME-2 to radiosonde observations is -2.7% for GOME-2A and -0.3% for GOME-2B. Against GPS observations, the median relative differences are 4.9 and 3.2% for GOME-2A and B, respectively. For water vapour total columns below 10 kg m-2, large wet biases are observed, especially against GPS observations. Conversely, at values above 50 kg m-2, GOME-2 generally underestimates both ground-based observations.

Combining airborne laser scanning and Landsat data for statistical modeling of soil carbon and tree biomass in Tanzanian Miombo woodlands.

PubMed

Egberth, Mikael; Nyberg, Gert; Næsset, Erik; Gobakken, Terje; Mauya, Ernest; Malimbwi, Rogers; Katani, Josiah; Chamuya, Nurudin; Bulenga, George; Olsson, Håkan

2017-12-01

Soil carbon and biomass depletion can be used to identify and quantify degraded soils, and by using remote sensing, there is potential to map soil conditions over large areas. Landsat 8 Operational Land Imager satellite data and airborne laser scanning data were evaluated separately and in combination for modeling soil organic carbon, above ground tree biomass and below ground tree biomass. The test site is situated in the Liwale district in southeastern Tanzania and is dominated by Miombo woodlands. Tree data from 15 m radius field-surveyed plots and samples of soil carbon down to a depth of 30 cm were used as reference data for tree biomass and soil carbon estimations. Cross-validated plot level error (RMSE) for predicting soil organic carbon was 28% using only Landsat 8, 26% using laser only, and 23% for the combination of the two. The plot level error for above ground tree biomass was 66% when using only Landsat 8, 50% for laser and 49% for the combination of Landsat 8 and laser data. Results for below ground tree biomass were similar to above ground biomass. Additionally it was found that an early dry season satellite image was preferable for modelling biomass while images from later in the dry season were better for modelling soil carbon. The results show that laser data is superior to Landsat 8 when predicting both soil carbon and biomass above and below ground in landscapes dominated by Miombo woodlands. Furthermore, the combination of laser data and Landsat data were marginally better than using laser data only.

Detailed assessment of pedestrian ground contact injuries observed from in-depth accident data.

PubMed

Shang, Shi; Otte, Dietmar; Li, Guibing; Simms, Ciaran

2018-01-01

Most pedestrians struck by vehicles receive injuries from contact with the vehicle and also from the subsequent ground contact. However, ground related pedestrian injuries have received little focus. This paper uses 1221 German pedestrian collision cases occurring between 2000 and 2015 to assess the distribution and risk factors for pedestrian ground related injuries. Results show that for MAIS 2, the ground accounted for 24% of cases, for MAIS 3 the ground accounted for 20% of cases and for MAIS 4-5, the ground accounted for 14% of cases. There were no AIS 6 ground related injuries, though there were several fatal cases where the ground was coded as the most serious injury. The head, thorax and spine dominate AIS 4-5 ground contact injuries. Vehicle impact speeds were higher for ground related AIS 4-5 compared to AIS 2 injury cases and the average impact speed for ground related injuries to the upper and lower extremities was lower than for body regions like head, thorax and spine. There was a significant age effect on pedestrian ground related injury outcome, with older pedestrians suffering more severe injuries and the median age for thorax injuries was higher than for all other body regions. There was no significant difference in the proportions of AIS 2+ head injuries produced by ground contact for more recent vehicles (model year since 2005) compared to older vehicles (model year before 2005). However, logistic regression analysis showed that the normalised bonnet leading-edge height is a risk factor for adult pedestrian AIS2+ ground related head injuries, and this provides empirical support for recent computational modelling predictions which implied a relationship between vehicle shape and pedestrian ground contact injuries. Considering the potential benefits of preventing pedestrian ground contact, for collisions below 40km/h two thirds of the injury costs would be eliminated if ground contact could be prevented, and even higher benefits are likely at lower speeds (20 and 30km/h). These data demonstrate the importance of ground related pedestrian injuries and show that vehicle shape influences pedestrian injury outcome in ground contact. The data therefore provides significant motivation for countermeasures to prevent or moderate pedestrian ground related injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.

Manganese availability is negatively associated with carbon storage in northern coniferous forest humus layers.

PubMed

Stendahl, Johan; Berg, Björn; Lindahl, Björn D

2017-11-14

Carbon sequestration below ground depends on organic matter input and decomposition, but regulatory bottlenecks remain unclear. The relative importance of plant production, climate and edaphic factors has to be elucidated to better predict carbon storage in forests. In Swedish forest soil inventory data from across the entire boreal latitudinal range (n = 2378), the concentration of exchangeable manganese was singled out as the strongest predictor (R 2  = 0.26) of carbon storage in the extensive organic horizon (mor layer), which accounts for one third of the total below ground carbon. In comparison, established ecosystem models applied on the same data have failed to predict carbon stocks (R 2  < 0.05), and in our study manganese availability overshadowed both litter production and climatic factors. We also identified exchangeable potassium as an additional strong predictor, however strongly correlated with manganese. The negative correlation between manganese and carbon highlights the importance of Mn-peroxidases in oxidative decomposition of recalcitrant organic matter. The results support the idea that the fungus-driven decomposition could be a critical factor regulating humus carbon accumulation in boreal forests, as Mn-peroxidases are specifically produced by basidiomycetes.

Using forest health monitoring data to integrate above and below ground carbon information

Treesearch

Barbara L. Conkling; Coeli M. Hoover; William D. Smith; Craig J. Palmer

2002-01-01

The national Forest Health Monitoring (FHM) program conducted a remeasurement study in 1999 to evaluate the usefulness and feasibility of collecting data needed for investigating carbon budgets in forests. This study indicated that FHM data are adequate for detecting a 20% change over 10 years (2% change per year) in percent total carbon and carbon content (MgC/ha)...

Correction: Domingues Franceschini, M.H.; et al. Intercomparison of Unmanned Aerial Vehicle and Ground-Based Narrow Band Spectrometers Applied to Crop Trait Monitoring in Organic Potato Production. Sensors 2017, 17, 1428.

PubMed

Domingues Franceschini, Marston Héracles; Bartholomeus, Harm; van Apeldoorn, Dirk; Suomalainen, Juha; Kooistra, Lammert

2017-10-02

The authors would like to correct Figure 13 and Table A2, as well as the text related to the data presented in both of them, as indicated below, considering that an error in the calculations involving Equation (2), described in the Section 2.8 of the Materials and Methods Section, resulted in the communication of incorrect values [...].

Detection of fresh ground water and a contaminant plume beneath Red Brook Harbor, Cape Cod, Massachusetts, 2000

USGS Publications Warehouse

McCobb, Timothy D.; LeBlanc, Denis R.

2002-01-01

Trichloroethene and tetrachloroethene were detected in ground water in a vertical interval from about 68 to 176 feet below sea level beneath the shoreline where the contaminant plume emanating from a capped landfill on the Massachusetts Military Reservation intersects Red Brook Harbor. The highest concentrations at the shoreline, about 15 micrograms per liter of trichloroethene and 1 microgram per liter of tetrachloroethene, were measured in samples from one well at about 176 feet below sea level. The concentrations of nutrients, such as nitrate and ammonium, and trace metals, such as iron and manganese, in these same samples are typical of uncontaminated ground water on Cape Cod. Fresh ground water (bulk electrical conductance less than 100 millisiemens per meter) is present beneath the harbor at 40 of 48 locations investigated within about 250 feet of the shoreline. Fresh ground water also was detected at one location approximately 450 feet from shore. The harbor bottom consists of soft sediments that range in thickness from 0 to greater than 20 feet and overlie sandy aquifer materials. Trichloroethene was detected at several locations in fresh ground water from the sandy aquifer materials beneath the harbor. The highest trichloroethene concentration, about 4.5 micrograms per liter, was measured about 450 feet from shore.

Community annotation experiment for ground truth generation for the i2b2 medication challenge

PubMed Central

Solti, Imre; Xia, Fei; Cadag, Eithon

2010-01-01

Objective Within the context of the Third i2b2 Workshop on Natural Language Processing Challenges for Clinical Records, the authors (also referred to as ‘the i2b2 medication challenge team’ or ‘the i2b2 team’ for short) organized a community annotation experiment. Design For this experiment, the authors released annotation guidelines and a small set of annotated discharge summaries. They asked the participants of the Third i2b2 Workshop to annotate 10 discharge summaries per person; each discharge summary was annotated by two annotators from two different teams, and a third annotator from a third team resolved disagreements. Measurements In order to evaluate the reliability of the annotations thus produced, the authors measured community inter-annotator agreement and compared it with the inter-annotator agreement of expert annotators when both the community and the expert annotators generated ground truth based on pooled system outputs. For this purpose, the pool consisted of the three most densely populated automatic annotations of each record. The authors also compared the community inter-annotator agreement with expert inter-annotator agreement when the experts annotated raw records without using the pool. Finally, they measured the quality of the community ground truth by comparing it with the expert ground truth. Results and conclusions The authors found that the community annotators achieved comparable inter-annotator agreement to expert annotators, regardless of whether the experts annotated from the pool. Furthermore, the ground truth generated by the community obtained F-measures above 0.90 against the ground truth of the experts, indicating the value of the community as a source of high-quality ground truth even on intricate and domain-specific annotation tasks. PMID:20819855

Concept and integration of an on-line quasi-operational airborne hyperspectral remote sensing system

NASA Astrophysics Data System (ADS)

Schilling, Hendrik; Lenz, Andreas; Gross, Wolfgang; Perpeet, Dominik; Wuttke, Sebastian; Middelmann, Wolfgang

2013-10-01

Modern mission characteristics require the use of advanced imaging sensors in reconnaissance. In particular, high spatial and high spectral resolution imaging provides promising data for many tasks such as classification and detecting objects of military relevance, such as camouflaged units or improvised explosive devices (IEDs). Especially in asymmetric warfare with highly mobile forces, intelligence, surveillance and reconnaissance (ISR) needs to be available close to real-time. This demands the use of unmanned aerial vehicles (UAVs) in combination with downlink capability. The system described in this contribution is integrated in a wing pod for ease of installation and calibration. It is designed for the real-time acquisition and analysis of hyperspectral data. The main component is a Specim AISA Eagle II hyperspectral sensor, covering the visible and near-infrared (VNIR) spectral range with a spectral resolution up to 1.2 nm and 1024 pixel across track, leading to a ground sampling distance below 1 m at typical altitudes. The push broom characteristic of the hyperspectral sensor demands an inertial navigation system (INS) for rectification and georeferencing of the image data. Additional sensors are a high resolution RGB (HR-RGB) frame camera and a thermal imaging camera. For on-line application, the data is preselected, compressed and transmitted to the ground control station (GCS) by an existing system in a second wing pod. The final result after data processing in the GCS is a hyperspectral orthorectified GeoTIFF, which is filed in the ERDAS APOLLO geographical information system. APOLLO allows remote access to the data and offers web-based analysis tools. The system is quasi-operational and was successfully tested in May 2013 in Bremerhaven, Germany.

Health-Related Quality of Life and Associated Factors of Frontline Railway Workers: A Cross-Sectional Survey in the Ankang Area, Shaanxi Province, China

PubMed Central

Zhang, Xiaona; Chen, Gang; Xu, Feng; Zhou, Kaina; Zhuang, Guihua

2016-01-01

After validation of the widely used health-related quality of life (HRQOL) generic measure, the Short Form 36 version 2 (SF-36v2), we investigated the HRQOL and associated factors of frontline railway workers in China. Ground workers, conductors, and train drivers were selected from Ankang Precinct by using a stratified cluster sampling technique. A total of 784 frontline railway workers participated in the survey. The reliability and validity of SF-36v2 was satisfactory. The physical component summary (PCS) scores of three subgroups attained the average range for the USA general population, whereas the mental component summary (MCS) scores were well below the range. Most domains scored below the norm, except for the physical functioning (PF) domain. Among three subgroups, train drivers reported significantly lower scores on MCS and six health domains (excluding PF and bodily pain (BP)). After controlled confounders, conductors had significantly higher PCS and MCS scores than ground workers. There is heterogeneity on risk factors among three subgroups, but having long or irregular working schedules was negatively associated with HRQOL in all subgroups. SF-36v2 is a reliable and valid HRQOL measurement in railway workers in China. The frontline railway workers’ physical health was comparative to American norms, whilst mental health was relatively worse. Long or irregular working schedules were the most important factors. PMID:27916919

Spatial patterns of sub-tidal seagrasses and their tissue nutrients in the Torres Strait, northern Australia: Implications for management

NASA Astrophysics Data System (ADS)

Sheppard, James K.; Carter, Alex B.; McKenzie, Len J.; Pitcher, C. Roland; Coles, Robert G.

2008-09-01

The distribution and nutritional profiles of sub-tidal seagrasses from the Torres Strait were surveyed and mapped across an area of 31,000 km 2. Benthic sediment composition, water depth, seagrass species type and nutrients were sampled at 168 points selected in a stratified representative pattern. Eleven species of seagrass were present at 56 (33.3%) of the sample points. Halophila spinulosa, Halophila ovalis, Cymodocea serrulata and Syringodium isoetifolium were the most common species and these were nutrient profiled. Sub-tidal seagrass distribution (and associated seagrass nutrient concentrations) was generally confined to northern-central and south-western regions of the survey area (

BOILING HOUSE, GROUND FLOOR. WAREHOUSE TO LEFT REAR, MASSECUITTE HEATERS ...

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

BOILING HOUSE, GROUND FLOOR. WAREHOUSE TO LEFT REAR, MASSECUITTE HEATERS ABOVE RIGHT, LOW GRADE CENTRIFUGALS BELOW. CRYSTALLIZER HOT WATER TANK TO REAR. VIEW FROM NORTHEAST - Lihue Plantation Company, Sugar Mill Building, Haleko Road, Lihue, Kauai County, HI

Hydrogeological investigation at Site 5, Willow Grove Naval Air Station/Joint Reserve Base, Horsham Township, Montgomery County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.

2002-01-01

The U.S. Geological Survey conducted borehole geophysical logging, collected and analyzed water-level data, and sampled sections of a rock core to determine the concentration of volatile organic compounds in the aquifer matrix of the Stockton Formation. Borehole geophysical logs were run in three monitor wells. At well 05MW04I, the vertical gradient was upward at depths above 42 feet below land surface (ft bls), downward between 42 and 82 ft bls, and upward below 82 ft bls. At well 05MW05I, a downward vertical gradient was present. At well 05MW12I, the vertical gradient was downward above 112 ft bls and upward below 112 ft bls.Three water-bearing fractures in a 17-foot long rock core from 23.5 to 40.5 ft bls were identified and sampled. Three samples were analyzed from each water-bearing fracture—at the fracture face, 2 centimeters (cm) below the fracture, and 4 cm below the fracture. Fifteen compounds were detected; however, concentrations of seven compounds were less than 1 microgram per kilogram (mg/kg) when detected. Concentrations of benzene (from 0.39 to 3.3 mg/kg), 1,1-dichloroethene (1,1-DCE) (from 0.15 to 13 mg/kg), 1,1,1-trichloroethane (TCA) (from 0.17 to 22 mg/kg), and trichloroethylene (TCE) (from 0.092 to 9.6 mg/kg) were detected in all samples. The highest concentrations detected were for toluene, which was detected at a concentration of 32 and 86 mg/kg in the samples from unweathered sandstone at 2 and 4 cm below the fracture, respectively. Concentrations generally decreased with distance below the fracture in the mudstone samples. Concentrations of benzene and toluene increased with distance below the fractures in the unweathered sandstone samples. Concentrations of 1,1-DCE, TCA, and TCE were higher in the mudstone samples than in the samples from sandstone. Toluene concentrations were higher in unweathered sandstone than in weathered sandstone or mudstone.The effect of the pumping of Horsham Water and Sewer Authority public supply well 26 (HWSA-26), 0.2 mile southwest of the base boundary, on groundwater levels on the base was determined by shutting the well down for 6 days to allow water levels to recover. Water levels in 22 nearby wells were measured. The only well (02MW01I) that showed an unambiguous response to the shutdown of well HWSA-26 is 1,350 feet directly along strike from well HWSA-26. The recovery of well 05MW11I in response to the shutdown of well HWSA-26 is masked by recharge from snowmelt but probably does not exceed about 0.2 feet on the basis of the water level in well 05MW11I, which showed a response to the pumping of well HWSA-26 that ranged from 0.5 to 0.15 foot.Horizontal gradients differ with depth, and the rate and direction of ground-water flow and contaminant movement is depth dependent. The potentiometric-surface map for water levels measured in wells screened between 5 and 44 ft bls in the aquifer shows a ground-water mound that is the high point on a regional ground-water divide. From this divide, ground water flows both northwest toward Park Creek and southeast toward Pennypack Creek. The hydraulic gradient around this mound is relatively flat to the southeast and particularly flat to the northwest. The potentiometric-surface map for water levels measured in wells screened between 40 and 100 ft bls in the aquifer shows a very flat hydraulic gradient. Differences in the elevation of the potentiometric surface are less than 2 feet. The potentiometric-surface map for water levels measured in wells screened between 105 and 179 ft bls in the aquifer shows a steep hydraulic gradient between Sites 5 and 2 and a relatively flat hydraulic gradient between Sites 5 and 3. Water levels measured on October 7, 1999, showed downward vertical head gradients for all well clusters at Site 5. Vertical gradients ranged from 0.01 at well cluster 05MW10 to 0.2 at cluster 05MW11. Most gradients were between 0.01 and 0.026. Vertical head gradients vary with time. The variability is caused by a difference in the magnitude of water-level fluctuations between shallow and the deep fractures. The difference in the magnitude of water-level fluctuations is because of differences in lithology and aquifer storativity.

Quadriceps force and anterior tibial force occur obviously later than vertical ground reaction force: a simulation study.

PubMed

Ueno, Ryo; Ishida, Tomoya; Yamanaka, Masanori; Taniguchi, Shohei; Ikuta, Ryohei; Samukawa, Mina; Saito, Hiroshi; Tohyama, Harukazu

2017-11-18

Although it is well known that quadriceps force generates anterior tibial force, it has been unclear whether quadriceps force causes great anterior tibial force during the early phase of a landing task. The purpose of the present study was to examine whether the quadriceps force induced great anterior tibial force during the early phase of a landing task. Fourteen young, healthy, female subjects performed a single-leg landing task. Muscle force and anterior tibial force were estimated from motion capture data and synchronized force data from the force plate. One-way repeated measures analysis of variance and the post hoc Bonferroni test were conducted to compare the peak time of the vertical ground reaction force, quadriceps force and anterior tibial force during the single-leg landing. In addition, we examined the contribution of vertical and posterior ground reaction force, knee flexion angle and moment to peak quadriceps force using multiple linear regression. The peak times of the estimated quadriceps force (96.0 ± 23.0 ms) and anterior tibial force (111.9 ± 18.9 ms) were significantly later than that of the vertical ground reaction force (63.5 ± 6.8 ms) during the single-leg landing. The peak quadriceps force was positively correlated with the peak anterior tibial force (R = 0.953, P < 0.001). Multiple linear regression analysis showed that the peak knee flexion moment contributed significantly to the peak quadriceps force (R 2  = 0.778, P < 0.001). The peak times of the quadriceps force and the anterior tibial force were obviously later than that of the vertical ground reaction force for the female athletes during successful single-leg landings. Studies have reported that the peak time of the vertical ground reaction force was close to the time of anterior cruciate ligament (ACL) disruption in ACL injury cases. It is possible that early contraction of the quadriceps during landing might induce ACL disruption as a result of excessive anterior tibial force in unanticipated situations in ACL injury cases.

Technique for direct measurement of magnetic entropy of solids: Results for dysprosium titanium oxide

NASA Technical Reports Server (NTRS)

Flood, D. J.

1974-01-01

A measurement technique was devised which permits direct observation of the magnetic entropy of solids as a function of applied magnetic field. Measurements were made of the magnetic entropy, in the temperature range 2 to 20 K, of polycrystalline samples of dysprosium titanium oxide (Dy2Ti2O7) to determine its suitability for use as the working substance of a magnetic refrigerator. Magnetization measurements were also made at 4.2 K and below to provide additional information on the nature of the compound. The measurements indicated that crystalline electric fields perturbed the ground state of the dysprosium ions, removed the 16-fold degeneracy predicted by Hund's rules, and left only a twofold degeneracy in its place. A positive, temperature independent contribution to the magnetization was observed in the saturation region, which indicated that the doublet ground-state wave function was perturbed by a nearby unpopulated upper energy level.

Analytical framework for modeling of long-range transport of fungal plant epidemics

NASA Astrophysics Data System (ADS)

Kogan, Oleg; O'Keeffe, Kevin; Schneider, David; Myers, Christopher; Analytical FrameworksInfectious Disease Dynamics Team

2015-03-01

A new framework for the study of long-range transport of fungal plant epidemics is proposed. The null nonlinear model includes advective transport through the free atmosphere, spore production on the ground, and transfer of spores between the ground and the advective atmospheric layer. The competition between the growth wave on the ground and the effect of the wind is most strongly reflected in upwind fronts, which can propagate into the wind for exponential initial conditions. If the rate of spore transfer into the advective layer is below critical, this happens for initital conditions with arbitrary steepness. Upwind fronts from localized initial conditions will propagate in the direction of the wind above this critical parameter, and will not propagate below it. On the other hand, the speed of the downwind front does not have a strong dependence on the rate of spore transfer between the advective layer and the ground. Thus, even vanishingly small, but finite transfer rates result in a substantial epidemic wave in the direction of the wind. We also consider the effect of an additional, random-walk like mechanism of transport through the near-ground atmospheric boundary layer, and attempt to understand which route dominates the transport over long distances.

Age, alcohol, and simulated altitude : effects on performance and breathalyzer scores.

DOT National Transportation Integrated Search

1988-01-01

Trained men in two groups, 30-39 (n=12) and 60-69 (n=13), each performed at the Multiple Task Performance Battery (MTPB) in four separate full-day sessions with and without alcohol (2.2 mL of 100-proof vodka per kg of body weight) at ground level and...

Contrasting land uses in Mediterranean agro-silvo-pastoral systems generated patchy diversity patterns of vascular plants and below-ground microorganisms.

PubMed

Bagella, Simonetta; Filigheddu, Rossella; Caria, Maria Carmela; Girlanda, Mariangela; Roggero, Pier Paolo

2014-12-01

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Defining Stability, Security, Transition, and Reconstruction (SSTR) Operations Requirements for Future Department of the Navy Training and Analytical Models and Simulations

DTIC Science & Technology

2008-09-01

43 B. WELL-DEFINED MEASURES ........................................................... 43 C. ESSENTIAL ELEMENTS OF ANALYSIS ( EEA ...45 D. EEA PROCESS FOR RESTORATION OF ESSENTIAL SERVICE - WATER...FBCB2 Force XXI Battle Command, Brigade-and-Below FM Army Field Manual EEA Essential Elements of Analysis EPG Electronic Proving Ground ESS

Meeting global policy commitments carbon sequestration and southern pine forests

Treesearch

Kurt H. Johnsen; David N. Wear; R. Oren; R.O. Teskey; Felipe Sanchez; Rodney E. Will; John Butnor; D. Markewitz; D. Richter; T. Rials; H.L. Allen; J. Seiler; D. Ellsworth; Christopher Maier; G. Katul; P.M. Dougherty

2001-01-01

In managed forests, the amount of carbon further sequestered will be determined by (1) the increased amount of carbon in standing biomass (resulting from land-use changes and increased productivity); (2) the amount of recalcitrant carbon remaining below ground at the end of rotations; and (3) the amount of carbon sequestered in products created from harvested wood....

Close Combat Tactical Trainer (CCTT). Cost and Training Effectiveness Analysis (CTEA). Volume 2. Main Report

DTIC Science & Technology

1991-05-01

Plans t(NI𔃻) tasks. The tics of the C17. (2) develop training strate- aflIsi was. conlducted in s~uppiort of a mile- gies for armor and mechanized...the point of impact on the target, and if the round impacto the ground or an object other than the intended target. The hit detection computations

Pesticides in Ground Water of the Maryland Coastal Plain

USGS Publications Warehouse

Denver, Judith M.; Ator, Scott W.

2006-01-01

Selected pesticides are detectable at low levels (generally less than 0.1 microgram per liter) in unconfined ground water in many parts of the Maryland Coastal Plain. Samples were recently collected (2001-04) from 47 wells in the Coastal Plain and analyzed for selected pesticides and degradate compounds (products of pesticide degradation). Most pesticide degradation occurs in the soil zone before infiltration to the water table, and degradates of selected pesticides were commonly detected in ground water, often at higher concentrations than their respective parent compounds. Pesticides and their degradates often occur in ground water in mixtures of multiple compounds, reflecting similar patterns in usage. All measured concentrations in ground water were below established standards for drinking water, and nearly all were below other health-based guidelines. Although drinking-water standards and guidelines are typically much higher than observed concentrations in ground water, they do not exist for many detected compounds (particularly degradates), or for mixtures of multiple compounds. The distribution of observed pesticide compounds reflects known usage patterns, as well as chemical properties and environmental factors that affect the fate and transport of these compounds in the environment. Many commonly used pesticides, such as glyphosate, pendimethalin, and 2,4-D were not detected in ground water, likely because they were sorbed onto organic matter or degraded in the soil zone. Others that are more soluble and (or) persistent, like atrazine, metolachlor, and several of their degradates, were commonly detected in ground water where they have been used. Atrazine, for example, an herbicide used primarily on corn, was most commonly detected in ground water on the Eastern Shore (where agriculture is common), particularly where soils are well drained. Conversely, dieldrin, an insecticide previously used heavily for termite control, was detected only on the Western Shore, where urban land is more common. Use of dieldrin was suspended in 1987, but this compound is relatively persistent in the environment, and several decades are typically required for ground water to move completely through the surficial aquifer. U.S. Department of the Interior U.S. Geological Survey USGS Fact Sheet FS 2006-3119 2006 Location of the Maryland Coastal Plain.

Sign Vocabulary in Deaf Toddlers Exposed to Sign Language since Birth

ERIC Educational Resources Information Center

Rinaldi, Pasquale; Caselli, Maria Cristina; Di Renzo, Alessio; Gulli, Tiziana; Volterra, Virginia

2014-01-01

Lexical comprehension and production is directly evaluated for the first time in deaf signing children below the age of 3 years. A Picture Naming Task was administered to 8 deaf signing toddlers (aged 2-3 years) who were exposed to Sign Language since birth. Results were compared with data of hearing speaking controls. In both deaf and hearing…

Explanations for Success and Failure by Low and Average School Achievers.

ERIC Educational Resources Information Center

Bond, Lynne A.; Johnson, Jeannette L.

Low and average school achievers in grades 1 and 2 and grades 4 and 5 made attributions for successes and failures on school related and unrelated tasks. Students in the low achievement group were participants of the Title I program, and tested a year below their age-mates on reading and math achievement. Students were given two booklets of four…

A Historical Search for the Occurrence of Habitable Ground Ice at the Phoenix Landing Site

NASA Technical Reports Server (NTRS)

Zent, Aaron P.

2006-01-01

A numerical model of the thermal history of Martian ground ice at the approximate location of the planned Phoenix landing site has been developed and used to identify instances of relatively warm ground ice over the last 10 Ma. Many terrestrial organisms are adapted to life at or below the freezing temperature of water, and we will use the approximate doubling time of terrestrial microbial populations as a function of temperature, is used as a metric against which to assess the "habitability" of Martian ground ice.

Multisensor Equipped Uav/ugv for Automated Exploration

NASA Astrophysics Data System (ADS)

Batzdorfer, S.; Bobbe, M.; Becker, M.; Harms, H.; Bestmann, U.

2017-08-01

The usage of unmanned systems for exploring disaster scenarios has become more and more important in recent times as a supporting system for action forces. These systems have to offer a well-balanced relationship between the quality of support and additional workload. Therefore within the joint research project ANKommEn - german acronym for Automated Navigation and Communication for Exploration - a system for exploration of disaster scenarios is build-up using multiple UAV und UGV controlled via a central ground station. The ground station serves as user interface for defining missions and tasks conducted by the unmanned systems, equipped with different environmental sensors like cameras - RGB as well as IR - or LiDAR. Depending on the exploration task results, in form of pictures, 2D stitched orthophoto or LiDAR point clouds will be transmitted via datalinks and displayed online at the ground station or will be processed in short-term after a mission, e.g. 3D photogrammetry. For mission planning and its execution, UAV/UGV monitoring and georeferencing of environmental sensor data, reliable positioning and attitude information is required. This is gathered using an integrated GNSS/IMU positioning system. In order to increase availability of positioning information in GNSS challenging scenarios, a GNSS-Multiconstellation based approach is used, amongst others. The present paper focuses on the overall system design including the ground station and sensor setups on the UAVs and UGVs, the underlying positioning techniques as well as 2D and 3D exploration based on a RGB camera mounted on board the UAV and its evaluation based on real world field tests.

The role of spatial organization in preference for color pairs.

PubMed

Schloss, Karen B; Palmer, Stephen E

2011-01-01

We investigated how spatial organization influences color-pair preference asymmetries: differential preference for one color pair over another when the pairs contain the same colors in opposite spatial configurations. Schloss and Palmer (2011, Attention, Perception, & Psychophysics 73 55-571) found weak figure ground preference asymmetries for small squares centered on large squares in aesthetic ratings. Here, we found robust preference asymmetries using a more sensitive forced-choice task: participants strongly prefer pairs with yellower, lighter figures on bluer, darker grounds (experiment 1). We also investigated which spatial factors influence these preference asymmetries. Relative area of the two component regions is clearly important, and perceived 3-D area of the 2-D displays (ie after the ground is amodally completed behind the figure) is more influential than 2-D area (experiment 2). Surroundedness is not required, because yellowness blueness effects were comparable for pairs in which the figure was surrounded by the ground, and for mosaic arrangements in which the regions were adjacent and separated by a gap (experiment 3). Lightness darkness effects, however, were opposite for figure ground versus mosaic organizations: people prefer figure-ground organizations in which smaller regions are lighter, but prefer mosaic organizations in which smaller regions are darker. Physiological, phenomenological, and ecological explanations of the reported results are discussed.

Research on Integrated Geophysics Detect Potential Ground Fissure in City

NASA Astrophysics Data System (ADS)

Qian, R.

2017-12-01

North China confined aquifer lied 70 to 200 meters below the earth's surface has been exploited for several decades, which resulted in confined water table declining and has generated a mass of ground fissure. Some of them has reached the surface and the other is developing. As it is very difficult to stop the ground fissure coming into being, measures of avoiding are often taken. It brings great potential risk to urban architecture and municipal engineering. It is very important to find out specific distribution and characteristic of potential ground fissure in city with high resolution. The ground fissure is concealed, therefor, geophysical method is an important technology to detecting concealed ground fissure. However, it is very difficult to detect the characteristics of the superficial part of ground fissure directly, as it lies dozens of meters below and has only scores of centimeters fault displacement. This paper studies applied ground penetration radar, surface wave and shallow refleciton seismic to detect ground fissure. It sets up model of surface by taking advantage of high resolution of ground penetrating radar data, constrains Reilay wave inversion and improves its resolution. The high resolution reflection seismic is good at detecting the geology structure. The data processing and interpretation technique is developmented to avoid the pitfall and improve the aliability of the rusult. The experiment has been conducted in Shunyi District, Beijing in 2016. 5 lines were settled to collect data of integrated geophysical method. Development zone of concealed ground fissure was found and its ultra shallow layer location was detected by ground penetrating radar. A trial trench of 6 meters in depth was dug and obvious ground fissure development was found. Its upper end was 1.5 meters beneath the earth's surface with displacement of 0.3 meters. The favorable effect of this detection has provided a new way for detecting ground fissure in cities of China, such as Beijing and Xi'an etc. Keyword: Ground Fissure, GPR, Surface Wave; Shallow Reflection Seismic

Familiar shapes attract attention in figure-ground displays.

PubMed

Nelson, Rolf A; Palmer, Stephen E

2007-04-01

We report five experiments that explore the effect of figure-ground factors on attention. We hypothesized that figural cues, such as familiar shape, would draw attention to the figural side in an attentional cuing task using bipartite figure-ground displays. The first two experiments used faces in profile as the familiar shape and found a perceptual advantage for targets presented on the meaningful side of the central contour in detection speed (Experiment 1) and discrimination accuracy (Experiment 2). The third experiment demonstrated the figural advantage in response time (RT) with nine other familiar shapes (including a sea horse, a guitar, a fir tree, etc.), but only when targets appeared in close proximity to the contour. A fourth experiment obtained a figural advantage in a discrimination task with the larger set of familiar shapes. The final experiment ruled out eye movements as a possible confounding factor by replicating the RT advantage for targets on the figural side of face displays when all trials containing eye movements were eliminated. The results are discussed in terms of ecological influences on attention, and are cast within the framework of Yantis and Jonides's hypothesis that attention is exogenously drawn to the onset of new perceptual objects. We argue that the figural side constitutes an "object" whereas the ground side does not, and that figural cues such as shape familiarity are effective in determining which areas represent objects.

Gender differences in active musculoskeletal stiffness. Part II. Quantification of leg stiffness during functional hopping tasks.

PubMed

Granata, K P; Padua, D A; Wilson, S E

2002-04-01

Leg stiffness was compared between age-matched males and females during hopping at preferred and controlled frequencies. Stiffness was defined as the linear regression slope between the vertical center of mass (COM) displacement and ground-reaction forces recorded from a force plate during the stance phase of the hopping task. Results demonstrate that subjects modulated the vertical displacement of the COM during ground contact in relation to the square of hopping frequency. This supports the accuracy of the spring-mass oscillator as a representative model of hopping. It also maintained peak vertical ground-reaction load at approximately three times body weight. Leg stiffness values in males (33.9+/-8.7 kN/m) were significantly (p<0.01) greater than in females (26.3+/-6.5 kN/m) at each of three hopping frequencies, 3.0, 2.5 Hz, and a preferred hopping rate. In the spring-mass oscillator model leg stiffness and body mass are related to the frequency of motion. Thus male subjects necessarily recruited greater leg stiffness to drive their heavier body mass at the same frequency as the lighter female subjects during the controlled frequency trials. However, in the preferred hopping condition the stiffness was not constrained by the task because frequency was self-selected. Nonetheless, both male and female subjects hopped at statistically similar preferred frequencies (2.34+/-0.22 Hz), therefore, the females continued to demonstrate less leg stiffness. Recognizing the active muscle stiffness contributes to biomechanical stability as well as leg stiffness, these results may provide insight into the gender bias in risk of musculoskeletal knee injury.

Silviculture of varietal loblolly pine plantations: second year impacts of spacing and silvicultural treatments on varieties with differing crown ideotypes

Treesearch

Lance A. Vickers; Thomas R. Fox; Jose L. Stape; Timothy J. Albaugh

2012-01-01

A long-term study has been established to address the following objectives: 1) Evaluate the crown ideotype approach to clonal testing in loblolly pine; 2) Determine impacts of increasing genetic uniformity on growth and uniformity of loblolly pine plantations; 3) Compare growth response, carbon allocation patterns (above and below ground), and ecophysiological...

Transient response of Salix cuttings to changing water level regimes

NASA Astrophysics Data System (ADS)

Gorla, L.; Signarbieux, C.; Turberg, P.; Buttler, A.; Perona, P.

2015-03-01

Sustainable water management requires an understanding of the effects of flow regulation on riparian ecomorphological processes. We investigated the transient response of Salix viminalis by examining the effect of water-level regimes on its above-ground and below-ground biomass. Four sets of Salix cuttings, three juveniles (in the first growing season) and one mature (1 year old), were planted and initially grown under the same water-level regime for 1 month. We imposed three different water-level regime treatments representing natural variability, a seasonal trend with no peaks, and minimal flow (characteristic of hydropower) consisting of a constant water level and natural flood peaks. We measured sap flux, stem water potential, photosynthesis, growth parameters, and final root architecture. The mature cuttings were not affected by water table dynamics, but the juveniles displayed causal relationships between the changing water regime, plant growth, and root distribution during a 2 month transient period. For example, a 50% drop in mean sap flux corresponded with a -1.5 Mpa decrease in leaf water potential during the first day after the water regime was changed. In agreement with published field observations, the cuttings concentrated their roots close to the mean water table of the corresponding treatment, allowing survival under altered conditions and resilience to successive stress events. Juvenile development was strongly impacted by the minimum flow regime, leading to more than 60% reduction of both above-ground and below-ground biomass, with respect to the other treatments. Hence, we suggest avoiding minimum flow regimes where Salix restoration is prioritized.

APPLICATION AND DEVELOPMENT OF APPROPRIATE TOOLS AND TECHNOLOGIES FOR COST-EFFECTIVE CARBON

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill Stanley; Sandra Brown; Ellen Hawes

2003-09-01

The Nature Conservancy is participating in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research project is ''Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration''. The objectives of the project are to: (1) improve carbon offset estimates produced in both the planning and implementation phases of projects; (2) build valid and standardized approaches to estimate project carbon benefits at a reasonable cost; and (3) lay the groundwork for implementing cost-effective projects,more » providing new testing ground for biodiversity protection and restoration projects that store additional atmospheric carbon. This Technical Progress Report discusses preliminary results of the six specific tasks that The Nature Conservancy is undertaking to answer research needs while facilitating the development of real projects with measurable greenhouse gas impacts. The research described in this report occurred between July 1, 2002 and June 30, 2003. The specific tasks discussed include: Task 1: carbon inventory advancements; Task 2: advanced videography testing; Task 3: baseline method development; Task 4: third-party technical advisory panel meetings; Task 5: new project feasibility studies; and Task 6: development of new project software screening tool.« less

Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill Stanley; Sandra Brown; Patrick Gonzalez

2004-07-10

The Nature Conservancy is participating in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research project is ''Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration''. The objectives of the project are to: (1) improve carbon offset estimates produced in both the planning and implementation phases of projects; (2) build valid and standardized approaches to estimate project carbon benefits at a reasonable cost; and (3) lay the groundwork for implementing cost-effective projects,more » providing new testing ground for biodiversity protection and restoration projects that store additional atmospheric carbon. This Technical Progress Report discusses preliminary results of the six specific tasks that The Nature Conservancy is undertaking to answer research needs while facilitating the development of real projects with measurable greenhouse gas impacts. The research described in this report occurred between July 1, 2002 and June 30, 2003. The specific tasks discussed include: Task 1: carbon inventory advancements; Task 2: remote sensing for carbon analysis; Task 3: baseline method development; Task 4: third-party technical advisory panel meetings; Task 5: new project feasibility studies; and Task 6: development of new project software screening tool.« less

In-Space Crew-Collaborative Task Scheduling

NASA Technical Reports Server (NTRS)

Jaap, John; Meyer, Patrick; Davis, Elizabeth; Richardson, Lea

2007-01-01

For all past and current human space missions, the final scheduling of tasks to be done in space has been devoid of crew control, flexibility, and insight. Ground controllers, with minimal input from the crew, schedule the tasks and uplink the timeline to the crew or uplink the command sequences to the hardware. Prior to the International Space Station (ISS), the crew could make requests about tomorrow s timeline, they could omit a task, or they could request that something in the timeline be delayed. This lack of control over one's own schedule has had negative consequences. There is anecdotal consensus among astronauts that control over their own schedules will mitigate the stresses of long duration missions. On ISS, a modicum of crew control is provided by the job jar. Ground controllers prepare a task list (a.k.a. "job jar") of non-conflicting tasks from which jobs can be chosen by the in space crew. Because there is little free time and few interesting non-conflicting activities, the task-list approach provides little relief from the tedium of being micro-managed by the timeline. Scheduling for space missions is a complex and laborious undertaking which usually requires a large cadre of trained specialists and suites of complex software tools. It is a giant leap from today s ground prepared timeline (with a job jar) to full crew control of the timeline. However, technological advances, currently in-work or proposed, make it reasonable to consider scheduling a collaborative effort by the ground-based teams and the in-space crew. Collaboration would allow the crew to make minor adjustments, add tasks according to their preferences, understand the reasons for the placement of tasks on the timeline, and provide them a sense of control. In foreseeable but extraordinary situations, such as a quick response to anomalies and extended or unexpected loss of signal, the crew should have the autonomous ability to make appropriate modifications to the timeline, extend the timeline, or even start over with a new timeline. The Vision for Space Exploration (VSE), currently being pursued by the National Aeronautics and Space Administration (NASA), will send humans to Mars in a few decades. Stresses on the human mind will be exacerbated by the longer durations and greater distances, and it will be imperative to implement stress-reducing innovations such as giving the crew control of their daily activities.

Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 1: Generic ground operations data

NASA Technical Reports Server (NTRS)

Byrd, Raymond J.

1990-01-01

This study was initiated to identify operations problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advance Launch System (ALS) program, the results of the Operationally Efficient Propulsion System Study (OEPSS) were organized into a series of OEPSS Data Books as follows: Volume 1, Generic Ground Operations Data; Volume 2, Ground Operations Problems; Volume 3, Operations Technology; Volume 4, OEPSS Design Concepts; and Volume 5, OEPSS Final Review Briefing, which summarizes the activities and results of the study. This volume presents ground processing data for a generic LOX/LH2 booster and core propulsion system based on current STS experience. The data presented includes: top logic diagram, process flow, activities bar-chart, loaded timelines, manpower requirements in terms of duration, headcount and skill mix per operations and maintenance instruction (OMI), and critical path tasks and durations.

Total Mercury and Methylmercury in the Great Egg Harbor River Watershed, New Jersey, USA

NASA Astrophysics Data System (ADS)

Barringer, J. L.; Riskin, M. L.; Szabo, Z.; Fischer, J. M.; Reilly, P. A.; Rosman, R.; Bonin, J. L.; Heckathorn, H. A.

2007-12-01

Hydrologic and biogeochemical conditions are important factors in the transport and distribution of mercury (Hg) in New Jersey Coastal Plain watersheds that contain extensive freshwater wetlands and where Hg bioaccumulation is of concern. U.S. Geological Survey studies found Hg concentrations in top predator fish from the Great Egg Harbor River mainstem that ranged from 2.9 to 4.5 mg/kg (dry wt.) and exceeded 10 ng/L in the watershed's acidic streams. An ongoing study with the N.J. Department of Environmental Protection indicates that atmospheric deposition of Hg to the wetlands and streams may be augmented by substantial contributions of Hg from ground water. Although background levels of Hg in water from the underlying aquifer typically are less than 10 ng/L, concentrations in water from more than 600 domestic wells in southern New Jersey have been shown to exceed the drinking-water maximum contaminant level of 2,000 ng/L. Therefore, to determine ground-water inputs to the streams, samples of ground water discharging to the tributaries and mainstem as well as streamwater samples collected during various flow conditions were analyzed for total Hg and methylmercury (MeHg). Total Hg concentrations in ground water discharging to the tributaries and mainstem were low to moderate (0.29-22 ng/L) in relatively undeveloped areas (including wetlands), but higher (36 and 177 ng/L) in two urban/suburban areas where much of the Hg was in particulate form. In recent and ongoing studies, total Hg concentrations in unfiltered samples of surface water, except those for one suburban tributary, have ranged from 2.13 to 37.7 ng/L. Concentrations in the suburban tributary have ranged from 50 ng/L during a dry period to 250 ng/L during a wet period. Hg concentrations in samples from a wetlands-embedded reach of the mainstem varied markedly with flow. In addition to increases in concentrations of total Hg, UV absorbance and concentrations of dissolved organic carbon also increased with flow after rain events, whereas pH and concentrations of dissolved oxygen and nitrate decreased. These flow-related changes apparently result from inputs of water that has percolated through acidic, reducing wetlands soils. The biogeochemical environment of these soils, on the basis of hydrogen sulfide odors detected during piezometer placement, supports sulfate reduction and likely promotes methylation of Hg. MeHg concentrations were 0.48 ng/L after a rainfall in discharge from 0.8 m below the streambed at a mainstem wetlands site. Downstream, where the channel briefly emerges from wetlands, MeHg was detectable during a dry period only in the hyporheic-zone water from 0.15 m below the streambed and in ground water from a depth of 0.3 m (0.15 ng/L and 0.05 ng/L, respectively). MeHg was not detected in the ground-water samples from deeper points below the streambeds, but concentrations in surface water ranged from 0.17 to 2.88 ng/L. The concentration from a tributary surrounded by urban/suburban development was highest. MeHg concentrations in mainstem water did not always increase with streamflow; variations in antecedent hydrologic conditions in the wetlands may explain the unpredictable relation of concentration to flow. Overall, total Hg appears to be contributed to the streams by both ground water and atmospheric deposition, with methylation taking place at shallow levels in wetlands soils and stream sediments.

Practical Application of Polarization and Light Control for Reduction of Reflected Glare.

ERIC Educational Resources Information Center

Crouch, C. L.; Kaufman, J. E.

1963-01-01

The role of reflected glare and visual viewing angles in near task performance is discussed, and following statements are reported--(1) a worker at a desk normally assumes a position in which his eyes traverse an area of work extending from a point approximately vertically below his eyes to a point not more than 40 degrees from the vertical, (2) a…

Seismic rupture and ground accelerations induced by CO 2 injection in the shallow crust

DOE PAGES

Cappa, Frédéric; Rutqvist, Jonny

2012-09-01

We present that because of the critically stressed nature of the upper crust, the injection of large volumes of carbon dioxide (CO 2) into shallow geological reservoirs can trigger seismicity and induce ground deformations when the injection increases the fluid pressure in the vicinity of potentially seismic faults. The increased fluid pressure reduces the strength against fault slip, allowing the stored elastic energy to be released in seismic events that can produce felt ground accelerations. Here, we seek to explore the likelihood ground motions induced by a CO 2 injection using hydromechanical modelling with multiphase fluid flow and dynamic rupture,more » including fault-frictional weakening. We extend the previous work of Cappa and Rutqvist, in which activation of a normal fault at critical stress may be possible for fast rupture nucleating by localized increase in fluid pressure and large decrease in fault friction. In this paper, we include seismic wave propagation generated by the rupture. For our assumed system and injection rate, simulations show that after a few days of injection, a dynamic fault rupture of few centimetres nucleates at the base of the CO 2 reservoir and grows bilaterally, both toward the top of the reservoir and outside. The rupture is asymmetric and affects a larger zone below the reservoir where the rupture is self-propagating (without any further pressure increase) as a result of fault-strength weakening. The acceleration and deceleration of the rupture generate waves and result in ground accelerations (~0.1–0.6 g) consistent with observed ground motion records. Finally, the maximum ground acceleration is obtained near the fault, and horizontal accelerations are generally markedly higher than vertical accelerations.« less

Exposure to airborne organophosphates originating from hydraulic and turbine oils among aviation technicians and loaders.

PubMed

Solbu, Kasper; Daae, Hanne Line; Thorud, Syvert; Ellingsen, Dag Gunnar; Lundanes, Elsa; Molander, Paal

2010-12-01

This study describes the potential for occupational exposure to organophosphates (OPs) originating from turbine and hydraulic oils, among ground personnel within the aviation industry. The OPs tri-n-butyl phosphate (TnBP), dibutyl phenyl phosphate (DBPP), triphenyl phosphate (TPP) and tricresyl phosphate (TCP) have been emphasized due to their use in such oils. Oil aerosol/vapor and total volatile organic compounds (tVOCs) in air were also determined. In total, 228 and 182 OPs and oil aerosol/vapor samples from technician and loader work tasks during work on 42 and 21 aircrafts, respectively, were collected in pairs. In general, the measured exposure levels were below the limit of quantification (LOQ) for 84%/98% (oil aerosol) and 82%/90% (TCP) of the samples collected during technician/loader work tasks. The air concentration ranges for all samples related to technician work were

Collection of liquid from below-ground location

DOEpatents

Phillips, S.J.; Alexander, R.G.

1995-05-30

A method is described for retrieving liquid from a below-ground collection area by permitting gravity flow of the liquid from the collection area to a first closed container; monitoring the level of the liquid in the closed container; and after the liquid reaches a given level in the first closed container, transferring the liquid to a second closed container disposed at a location above the first closed container, via a conduit, by introducing into the first closed container a gas which is substantially chemically inert with respect to the liquid, the gas being at a pressure sufficient to propel the liquid from the first closed container to the second closed container. 3 figs.

The root/rhizome system of seagrasses: an asset and a burden

NASA Astrophysics Data System (ADS)

Hemminga, M. A.

1998-06-01

Large-scale declines in seagrass vegetation have been frequently observed in recent decades. Many of these declines can be traced to the reduction of light levels in the water column. In this paper, it is argued that the root/rhizome system offers a competitive advantage in nutrient-poor waters, but that it makes the plant vulnerable when changes in water quality lead to reduction of incident light. Seagrasses are capable of exploiting the nutrient stocks of both the water column and the sediment pore water, by leaves and roots, respectively. A survey of the literature shows that the median concentrations of water-column ammonium and phosphate in seagrass beds worldwide are 1.7 and 0.35 μM, respectively, whereas the same compounds in the pore water of the root zone reach median concentrations of 60 and 6.5 μM. The dual possibilities for nutrient uptake may underlie the apparent lack of strongly developed nutrient conservation strategies in seagrasses. The possession of roots becomes a disadvantage when the photosynthetically active radiation available to the plants decreases. At saturating light levels, the maximum rate of net photosynthesis (measured as O 2 production) of the leaves typically exceeds leaf respiration (measured as O 2 consumption) about 5 times. In low-light environments, the respiring below-ground biomass (which can greatly exceed the above-ground biomass) can be a considerable burden to the carbon balance of the plant, limiting its survival potential. In addition, secondary and tertiary effects of light reduction involving the roots and rhizomes may undermine plant vitality as well. Leaf photosynthesis is the major source of oxygen for the roots and rhizomes. Hence, decreased photosynthetic activity following light reduction may lead to hypoxic or anoxic conditions in the below-ground organs, presumably making them vulnerable to carbon starvation. A decreased flux of oxygen to the roots and rhizomes also restricts the possibilities for oxidation of sediment sulphide, a known phytotoxin, because release of oxygen into the rhizosphere will diminish. The cascade effects of light reduction which involve the below-ground organs of seagrasses are little studied. More insight into the functioning of the root/rhizome system and into the interactions between this system and the sediment environment is needed to fully understand the vulnerability of seagrasses to light reduction.

A second generation expert system for checking and diagnosing AXAF's electric power system

NASA Technical Reports Server (NTRS)

Bykat, Alex

1992-01-01

AXAF - Advanced X-ray Astrophysics Facility - is a third NASA's great space observatory. Each of these observatories is intended to cover different parts of the electromagnetic spectrum (x-ray for AXAF) and to provide high resolution images of celestial sources in our universe. While the spacecraft is in orbit, the electric power system (EPS) performance is monitored via sensors measuring voltages, currents, pressures, and temperatures. The sensor data are sent from the spacecraft to the ground station as telemetry and analyzed on arrival. Monitoring, diagnosis and maintenance of such EPS is an arduous task which requires expertise and constant attention of the ground personnel. To help the ground crew in this task, much of it should be automated and delegated to expert systems, which draw engineer's attention to possible malfunctions and allows him to review the telemetry to determine the source of the trouble, diagnose the suspected fault and to propose a corrective action. Those systems are built on assumptions such as: (1) domain knowledge is available and can be represented as a set of rules; (2) domain knowledge is circumscribed, static, and monotonic; and (3) expert decision making can be emulated by a logical inference mechanism.

Space station operations task force. Panel 2 report: Ground operations and support systems

NASA Technical Reports Server (NTRS)

1987-01-01

The Ground Operations Concept embodied in this report provides for safe multi-user utilization of the Space Station, eases user integration, and gives users autonomy and flexibility. It provides for meaningful multi-national participation while protecting U.S. interests. The concept also supports continued space operations technology development by maintaining NASA expertise and enabling technology evolution. Given attention here are pre/post flight operations, logistics, sustaining engineering/configuration management, transportation services/rescue, and information systems and communication.

Mission Operations with an Autonomous Agent

NASA Technical Reports Server (NTRS)

Pell, Barney; Sawyer, Scott R.; Muscettola, Nicola; Smith, Benjamin; Bernard, Douglas E.

1998-01-01

The Remote Agent (RA) is an Artificial Intelligence (AI) system which automates some of the tasks normally reserved for human mission operators and performs these tasks autonomously on-board the spacecraft. These tasks include activity generation, sequencing, spacecraft analysis, and failure recovery. The RA will be demonstrated as a flight experiment on Deep Space One (DSI), the first deep space mission of the NASA's New Millennium Program (NMP). As we moved from prototyping into actual flight code development and teamed with ground operators, we made several major extensions to the RA architecture to address the broader operational context in which PA would be used. These extensions support ground operators and the RA sharing a long-range mission profile with facilities for asynchronous ground updates; support ground operators monitoring and commanding the spacecraft at multiple levels of detail simultaneously; and enable ground operators to provide additional knowledge to the RA, such as parameter updates, model updates, and diagnostic information, without interfering with the activities of the RA or leaving the system in an inconsistent state. The resulting architecture supports incremental autonomy, in which a basic agent can be delivered early and then used in an increasingly autonomous manner over the lifetime of the mission. It also supports variable autonomy, as it enables ground operators to benefit from autonomy when L'@ey want it, but does not inhibit them from obtaining a detailed understanding and exercising tighter control when necessary. These issues are critical to the successful development and operation of autonomous spacecraft.

Conjunctive-use optimization model and sustainable-yield estimation for the Sparta aquifer of southeastern Arkansas and north-central Louisiana

USGS Publications Warehouse

McKee, Paul W.; Clark, Brian R.; Czarnecki, John B.

2004-01-01

Conjunctive-use optimization modeling was done to assist water managers and planners by estimating the maximum amount of ground water that hypothetically could be withdrawn from wells within the Sparta aquifer indefinitely without violating hydraulic-head or stream-discharge constraints. The Sparta aquifer is largely a confined aquifer of regional importance that comprises a sequence of unconsolidated sand units that are contained within the Sparta Sand. In 2000, more than 35.4 million cubic feet per day (Mft3/d) of water were withdrawn from the aquifer by more than 900 wells, primarily for industry, municipal supply, and crop irrigation in Arkansas. Continued, heavy withdrawals from the aquifer have caused several large cones of depression, lowering hydraulic heads below the top of the Sparta Sand in parts of Union and Columbia Counties and several areas in north-central Louisiana. Problems related to overdraft in the Sparta aquifer can result in increased drilling and pumping costs, reduced well yields, and degraded water quality in areas of large drawdown. A finite-difference ground-water flow model was developed for the Sparta aquifer using MODFLOW, primarily in eastern and southeastern Arkansas and north-central Louisiana. Observed aquifer conditions in 1997 supported by numerical simulations of ground-water flow show that continued pumping at withdrawal rates representative of 1990 - 1997 rates cannot be sustained indefinitely without causing hydraulic heads to drop substantially below the top of the Sparta Sand in southern Arkansas and north-central Louisiana. Areas of ground-water levels below the top of the Sparta Sand have been designated as Critical Ground-Water Areas by the State of Arkansas. A steady-state conjunctive-use optimization model was developed to simulate optimized surface-water and ground-water withdrawals while maintaining hydraulic-head and streamflow constraints, thus determining the 'sustainable yield' for the aquifer. Initial attempts to estimate sustainable yield using simulated 1997 hydraulic heads as initial heads in Scenario 1 and 100 percent of the baseline 1990-1997 withdrawal rate as the lower specified limit in Scenario 2 led to infeasible results. Sustainable yield was estimated successfully for scenario 3 with three variations on the upper limit of withdrawal rates. Additionally, ground-water withdrawals in Union County were fixed at 35.6 percent of the baseline 1990-1997 withdrawal rate in Scenario 3. These fixed withdrawals are recognized by the Arkansas Soil and Water Conservation Commission to be sustainable as determined in a previous study. The optimized solutions maintained hydraulic heads at or above the top of the Sparta Sand (except in the outcrop areas where unconfined conditions occur) and streamflow within the outcrop areas was maintained at or above minimum levels. Scenario 3 used limits of 100, 150, and 200 percent of baseline 1990-1997 withdrawal rates for the upper specified limit on 1,119 withdrawal decision variables (managed wells) resulting in estimated sustainable yields ranging from 11.6 to 13.2 Mft3/d in Arkansas and 0.3 to 0.5 Mft3/d in Louisiana. Assuming the total 2 Conjunctive-Use Optimization Model and Sustainable-Yield Estimation for the Sparta Aquifer of Southeastern Arkansas and North-Central Louisiana water demand is equal to the baseline 1990-1997 withdrawal rates, the sustainable yields estimated from the three scenarios only provide 52 to 59 percent of the total ground-water demand for Arkansas; the remainder is defined as unmet demand that could be obtained from large, sustainable surface-water withdrawals.

Potentiometric surface of the middle Potomac Aquifer in Virginia 1993

USGS Publications Warehouse

Hammond, E.C.; McFarland, E.R.; Focazio, M.J.

1994-01-01

Ground-water level measurements from 50 wells in the middle Potomac aquifer in the Coastal Plain Physiographic Province of Virginia in 1993 were used to prepare a map of the potentiometric surface of the aquifer. The map shows the potentiometric surface of the middle Potomac aquifer sharply declining eastward from nearly 100 feet above sear level near the western boundary of the aquifer to 20 feet below sea level, and continues declining gradually toward the Chesapeake Bay and Atlantic Ocean. A cone of depression is apparent around well fields in Franklin, Virginia. The potentiometric surface also appears to be affected by pumping in the area of Henrico County and Hanover County, Virginia. The highest ground-water-level measurement was 89 feet above sea level in Chesterfield County near Richmond, and the lowest ground-water-level measurement was 179 feet below sea level in southeastern Isle of Wight County, Virginia.

Ground-Water Quality Data in the Middle Sacramento Valley Study Unit, 2006 - Results from the California GAMA Program

USGS Publications Warehouse

Schmitt, Stephen J.; Fram, Miranda S.; Milby Dawson, Barbara J.; Belitz, Kenneth

2008-01-01

Ground-water quality in the approximately 3,340 square mile Middle Sacramento Valley study unit (MSACV) was investigated from June through September, 2006, as part of the California Groundwater Ambient Monitoring and Assessment (GAMA) program. The GAMA Priority Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Middle Sacramento Valley study was designed to provide a spatially unbiased assessment of raw ground-water quality within MSACV, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 108 wells in Butte, Colusa, Glenn, Sutter, Tehama, Yolo, and Yuba Counties. Seventy-one wells were selected using a randomized grid-based method to provide statistical representation of the study unit (grid wells), 15 wells were selected to evaluate changes in water chemistry along ground-water flow paths (flow-path wells), and 22 were shallow monitoring wells selected to assess the effects of rice agriculture, a major land use in the study unit, on ground-water chemistry (RICE wells). The ground-water samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], gasoline oxygenates and degradates, pesticides and pesticide degradates, and pharmaceutical compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, and carbon-14, and stable isotopes of hydrogen, oxygen, nitrogen, and carbon), and dissolved noble gases also were measured to help identify the sources and ages of the sampled ground water. Quality-control samples (blanks, replicates, laboratory matrix spikes) were collected at approximately 10 percent of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the ground-water samples. Differences between replicate samples were within acceptable ranges, indicating acceptably low variability. Matrix spike recoveries were within acceptable ranges for most constituents. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only and are not indicative of compliance or noncompliance with regulatory thresholds. Most constituents that were detected in ground-water samples were found at concentrations below drinking-water thresholds. VOCs were detected in less than one-third and pesticides and pesticide degradates in just over one-half of the grid wells, and all detections of these constituents in samples from all wells of the MSACV study unit were below health-based thresholds. All detections of trace elements in samples from MSACV grid wells were below health-based thresholds, with the exceptions of arsenic and boro

Is Obsidian Hydration Dating Affected by Relative Humidity?

USGS Publications Warehouse

Friedman, I.; Trembour, F.W.; Smith, G.I.; Smith, F.L.

1994-01-01

Experiments carried out under temperatures and relative humidities that approximate ambient conditions show that the rate of hydration of obsidian is a function of the relative humidity, as well as of previously established variables of temperature and obsidian chemical composition. Measurements of the relative humidity of soil at 25 sites and at depths of between 0.01 and 2 m below ground show that in most soil environments, at depths below about 0.25 m, the relative humidity is constant at 100%. We have found that the thickness of the hydrated layer developed on obsidian outcrops exposed to the sun and to relative humidities of 30-90% is similar to that formed on other portions of the outcrop that were shielded from the sun and exposed to a relative humidity of approximately 100%. Surface samples of obsidian exposed to solar heating should hydrate more rapidly than samples buried in the ground. However, the effect of the lower mean relative humidity experiences by surface samples tends to compensate for the elevated temperature, which may explain why obsidian hydration ages of surface samples usually approximate those derived from buried samples.

ENVIROGEN PROPANE BIOSTIMULATION TECHNOLOGY FOR THE IN-SITU TREATMENT OF MTBE-CONTAMINATED GROUND WATER INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

The primary objective of the Biostimulation Technology Evaluation was to determine if biodegradation was occurring in a ground-water Test Plot to a sufficient degree to reduce intrinsic MTBE to the State of California's treatability criteria of 5 mg/L or below. The evaluation wa...

Variability of site response in Seattle, Washington

USGS Publications Warehouse

Hartzell, S.; Carver, D.; Cranswick, E.; Frankel, A.

2000-01-01

Ground motion from local earthquakes and the SHIPS (Seismic Hazards Investigation in Puget Sound) experiment is used to estimate site amplification factors in Seattle. Earthquake and SHIPS records are analyzed by two methods: (1) spectral ratios relative to a nearby site on Tertiary sandstone, and (2) a source/site spectral inversion technique. Our results show site amplifications between 3 and 4 below 5 Hz for West Seattle relative to Tertiary rock. These values are approximately 30% lower than amplification in the Duwamish Valley on artificial fill, but significantly higher than the calculated range of 2 to 2.5 below 5 Hz for the till-covered hills east of downtown Seattle. Although spectral amplitudes are only 30% higher in the Duwamish Valley compared to West Seattle, the duration of long-period ground motion is significantly greater on the artificial fill sites. Using a three-dimensional displacement response spectrum measure that includes the effects of ground-motion duration, values in the Duwamish Valley are 2 to 3 times greater than West Seattle. These calculations and estimates of site response as a function of receiver azimuth point out the importance of trapped surface-wave energy within the shallow, low-velocity, sedimentary layers of the Duwamish Valley. One-dimensional velocity models yield spectral amplification factors close to the observations for till sites east of downtown Seattle and the Duwamish Valley, but underpredict amplifications by a factor of 2 in West Seattle. A two-dimensional finite-difference model does equally well for the till sites and the Duwamish Valley and also yields duration estimates consistent with the observations for the Duwamish Valley. The two-dimensional model, however, still underpredicts amplification in West Seattle by up to a factor of 2. This discrepancy is attributed to 3D effects, including basin-edge-induced surface waves and basin-geometry-focusing effects, caused by the proximity of the Seattle thrust fault and the sediment-filled Seattle basin.

Test holes drilled in support of ground-water investigations, Project Gnome, Eddy County, New Mexico

USGS Publications Warehouse

Cooper, J.B.

1962-01-01

Project Gnome is a proposed underground nuclear shot to be detonated within a massive salt bed in Eddy County, N. Mex. Potable and neat potable ground water is present in rocks above the salt and is being studied in relation to this nuclear event. This report presents details of two test holes which were drilled to determine ground-water conditions in the near vicinity of the shot point. A well-defined aquifer is present at the site of USGS test hole 1, about 1,000 feet south of the access shaft to the underground shot point. Water with 75 feet of artesian pressure head is contained in the Culebra dolomite member of the Rustler formation. The dolomite aquifer is 32 feet thick and its top lies at a depth of 517 feet below land surface. The aquifer yielded 100 gpm (gallons per minute) with a drawdown of 40 feet during a pumping period of 24 hours. Water was not found in rocks above or below the Culebra dolomite. At the site of USGS test hole 2, about 2 miles southwest of the access shaft no distinctive aquifer exists. About one-half gpm was yielded to the well from the rocks between the Culebra dolomite and the top of the salt. Water could not be detected in the Culebra dolomite or overlying rocks. The report contains drawdown and recovery curves of yield tests, drilling-time charts, and electric logs. The data are given in tables; they include summaries of hole construction, sample description logs, water measurements, drilling-time logs, and water analyses.

Effects of Selected Task Performance Criteria at Initiating Adaptive Task Real locations

NASA Technical Reports Server (NTRS)

Montgomery, Demaris A.

2001-01-01

In the current report various performance assessment methods used to initiate mode transfers between manual control and automation for adaptive task reallocation were tested. Participants monitored two secondary tasks for critical events while actively controlling a process in a fictional system. One of the secondary monitoring tasks could be automated whenever operators' performance was below acceptable levels. Automation of the secondary task and transfer of the secondary task back to manual control were either human- or machine-initiated. Human-initiated transfers were based on the operator's assessment of the current task demands while machine-initiated transfers were based on the operators' performance. Different performance assessment methods were tested in two separate experiments.

Shallow ground-water quality beneath rice areas in the Sacramento Valley, California, 1997

USGS Publications Warehouse

Dawson, Barbara J.

2001-01-01

In 1997, the U.S. Geological Survey installed and sampled 28 wells in rice areas in the Sacramento Valley as part of the National Water-Quality Assessment Program. The purpose of the study was to assess the shallow ground-water quality and to determine whether any effects on water quality could be related to human activities and particularly rice agriculture. The wells installed and sampled were between 8.8 and 15.2 meters deep, and water levels were between 0.4 and 8.0 meters below land surface. Ground-water samples were analyzed for 6 field measurements, 29 inorganic constituents, 6 nutrient constituents, dissolved organic carbon, 86 pesticides, tritium (hydrogen- 3), deuterium (hydrogen-2), and oxygen-18. At least one health-related state or federal drinking-water standard (maximum contaminant or long-term health advisory level) was exceeded in 25 percent of the wells for barium, boron, cadmium, molybdenum, or sulfate. At least one state or federal secondary maximum contaminant level was exceeded in 79 percent of the wells for chloride, iron, manganese, specific conductance, or dissolved solids. Nitrate and nitrite were detected at concentrations below state and federal 2000 drinking-water standards; three wells had nitrate concentrations greater than 3 milligrams per liter, a level that may indicate impact from human activities. Ground-water redox conditions were anoxic in 26 out of 28 wells sampled (93 percent). Eleven pesticides and one pesticide degradation product were detected in ground-water samples. Four of the detected pesticides are or have been used on rice crops in the Sacramento Valley (bentazon, carbofuran, molinate, and thiobencarb). Pesticides were detected in 89 percent of the wells sampled, and rice pesticides were detected in 82 percent of the wells sampled. The most frequently detected pesticide was the rice herbicide bentazon, detected in 20 out of 28 wells (71 percent); the other pesticides detected have been used for rice, agricultural, and non-agricultural purposes. All pesticide concentrations were below state and federal 2000 drinking-water standards. The relation of the ground-water quality to natural processes and human activities was tested using statistical methods (Spearman rank correlation, Kruskal?Wallis, or rank-sum tests) to determine whether an influence from rice land-use or other human activities on ground-water chemistry could be identified. The detection of pesticides in 89 percent of the wells sampled indicates that human activities have affected shallow ground-water quality. Concentrations of dissolved solids and inorganic constituents that exceeded state or federal 2000 drinking-water standards showed a statistical relation to geomorphic unit. This is interpreted as a relation to natural processes and variations in geology in the Sacramento River Basin; the high concentrations of dissolved solids and most inorganic constituents did not appear to be related to rice land use. No correlation was found between nitrate concentration and pesticide occurrence, indicating that an absence of high nitrate concentrations is not a predictor of an absence of pesticide contamination in areas with reducing ground-water conditions in the Sacramento Valley. Tritium concentrations, pesticide detections, stable isotope data, and dissolved-solids concentrations suggest that shallow ground water in the ricegrowing areas of the Sacramento Valley is a mix of recently recharged ground water containing pesticides, nitrate, and tritium, and unknown sources of water that contains high concentrations of dissolved solids and some inorganic constituents and is enriched in oxygen-18. Evaporation of applied irrigation water, which leaves behind salt, accounts for some of the elevated concentrations of dissolved solids. More work needs to be done to understand the connections between the land surface, shallow ground water, deep ground water, and the drinking-water supplies in the Sacramento Valley.

Evaluation of the geologic and hydrologic factors related to the waste-storage potential of Mesozoic aquifers in the southern part of the Atlantic Coastal Plain, South Carolina and Georgia

USGS Publications Warehouse

Brown, Philip M.; Brown, D.L.; Reid, M.S.; Lloyd, O.B.

1979-01-01

The report describes the subsurface distribution of rocks of Cretaceous to Late Jurassic( ) age in the Atlantic Coastal Plain , South Carolina, and Georgia, and examines their potential for deep-well waste storage into th part of the regional sediment mass which lies below the deepest zones containing usable ground waters. For the study, usable ground water is considered to be that which contains less than 10,000 mg/L dissolved solids. Using a group of geohydrologic parameters derived from or combining 21 categories of basic data, established from study and interpretation of well cuttings and geophysical logs, a series of 32 regional maps and 8 stratigraphic cross sections was constructed. For each of the eight geologic units delineated in the subsurface, the maps illustrate the distribution of waste-storage potential in terms of areal extent, depth below land surface, sand-shale geometry, and the approximate sodium chloride concentration of a unit 's nonusable ground water. In areas where the geologic units contain nonusable ground water, the depth below land surface and the thickness of potential waste-storage reservoir and reservoir-seal combinations are variable. The range in variability appears to be broad enough to meet the need for a wide choice among the geologic requirements that would normally be considered in selecting specific waste-storage sites for detailed examination. (Woodard-USGS)

Above- and below-ground carbon stocks in an indigenous tree (Mytilaria laosensis) plantation chronosequence in subtropical China.

PubMed

Ming, Angang; Jia, Hongyan; Zhao, Jinlong; Tao, Yi; Li, Yuanfa

2014-01-01

More than 60% of the total area of tree plantations in China is in subtropical, and over 70% of subtropical plantations consist of pure stands of coniferous species. Because of the poor ecosystem services provided by pure coniferous plantations and the ecological instability of these stands, a movement is under way to promote indigenous broadleaf plantation cultivation as a promising alternative. However, little is known about the carbon (C) stocks in indigenous broadleaf plantations and their dependence on stand age. Thus, we studied above- and below-ground biomass and C stocks in a chronosequence of Mytilaria laosensis plantations in subtropical China; stands were 7, 10, 18, 23, 29 and 33 years old. Our assessments included tree, shrub, herb and litter layers. We used plot-level inventories and destructive tree sampling to determine vegetation C stocks. We also measured soil C stocks by analyses of soil profiles to 100 cm depth. C stocks in the tree layer dominated the above-ground ecosystem C pool across the chronosequence. C stocks increased with age from 7 to 29 years and plateaued thereafter due to a reduction in tree growth rates. Minor C stocks were found in the shrub and herb layers of all six plantations and their temporal fluctuations were relatively small. C stocks in the litter and soil layers increased with stand age. Total above-ground ecosystem C also increased with stand age. Most increases in C stocks in below-ground and total ecosystems were attributable to increases in soil C content and tree biomass. Therefore, considerations of C sequestration potential in indigenous broadleaf plantations must take stand age into account.

Above- and Below-Ground Carbon Stocks in an Indigenous Tree (Mytilaria laosensis) Plantation Chronosequence in Subtropical China

PubMed Central

Zhao, Jinlong; Tao, Yi

2014-01-01

More than 60% of the total area of tree plantations in China is in subtropical, and over 70% of subtropical plantations consist of pure stands of coniferous species. Because of the poor ecosystem services provided by pure coniferous plantations and the ecological instability of these stands, a movement is under way to promote indigenous broadleaf plantation cultivation as a promising alternative. However, little is known about the carbon (C) stocks in indigenous broadleaf plantations and their dependence on stand age. Thus, we studied above- and below-ground biomass and C stocks in a chronosequence of Mytilaria laosensis plantations in subtropical China; stands were 7, 10, 18, 23, 29 and 33 years old. Our assessments included tree, shrub, herb and litter layers. We used plot-level inventories and destructive tree sampling to determine vegetation C stocks. We also measured soil C stocks by analyses of soil profiles to 100 cm depth. C stocks in the tree layer dominated the above-ground ecosystem C pool across the chronosequence. C stocks increased with age from 7 to 29 years and plateaued thereafter due to a reduction in tree growth rates. Minor C stocks were found in the shrub and herb layers of all six plantations and their temporal fluctuations were relatively small. C stocks in the litter and soil layers increased with stand age. Total above-ground ecosystem C also increased with stand age. Most increases in C stocks in below-ground and total ecosystems were attributable to increases in soil C content and tree biomass. Therefore, considerations of C sequestration potential in indigenous broadleaf plantations must take stand age into account. PMID:25343446

Concepts for a theoretical and experimental study of lifting rotor random loads and vibrations (further experiments with progressing/regressing rotor flapping modes), Phase 7-C

NASA Technical Reports Server (NTRS)

Hohenemser, K. H.; Crews, S. T.

1973-01-01

The experiments with progressing/regressing forced rotor flapping modes have been extended in several directions and the data processing method has been considerably refined. The 16 inch hingeless 2-bladed rotor model was equipped with a new set of high precision blades which removed previously encountered tracking difficulties at high advance ratio, so that tests up to .8 rotor advance ratio could be conducted. In addition to data with 1.20 blade natural flapping frequency data at 1.10 flapping frequency were obtained. Outside the wind tunnel, tests with a ground plate located at different distances below the rotor were conducted while recording the dynamic downflow at a station .2R below the rotor plane with a hot wire anemometer.

Simultaneous and synergistic profiling of cloud and drizzle properties using ground-based observations

NASA Astrophysics Data System (ADS)

Rusli, Stephanie P.; Donovan, David P.; Russchenberg, Herman W. J.

2017-12-01

Despite the importance of radar reflectivity (Z) measurements in the retrieval of liquid water cloud properties, it remains nontrivial to interpret Z due to the possible presence of drizzle droplets within the clouds. So far, there has been no published work that utilizes Z to identify the presence of drizzle above the cloud base in an optimized and a physically consistent manner. In this work, we develop a retrieval technique that exploits the synergy of different remote sensing systems to carry out this task and to subsequently profile the microphysical properties of the cloud and drizzle in a unified framework. This is accomplished by using ground-based measurements of Z, lidar attenuated backscatter below as well as above the cloud base, and microwave brightness temperatures. Fast physical forward models coupled to cloud and drizzle structure parameterization are used in an optimal-estimation-type framework in order to retrieve the best estimate for the cloud and drizzle property profiles. The cloud retrieval is first evaluated using synthetic signals generated from large-eddy simulation (LES) output to verify the forward models used in the retrieval procedure and the vertical parameterization of the liquid water content (LWC). From this exercise it is found that, on average, the cloud properties can be retrieved within 5 % of the mean truth. The full cloud-drizzle retrieval method is then applied to a selected ACCEPT (Analysis of the Composition of Clouds with Extended Polarization Techniques) campaign dataset collected in Cabauw, the Netherlands. An assessment of the retrieval products is performed using three independent methods from the literature; each was specifically developed to retrieve only the cloud properties, the drizzle properties below the cloud base, or the drizzle fraction within the cloud. One-to-one comparisons, taking into account the uncertainties or limitations of each retrieval, show that our results are consistent with what is derived using the three independent methods.

Changes in frozen ground and vegetation on northern slopes of the Bayan Har Mountains on northeastern Qinghai-Tibetan Plateau, Southwest China

NASA Astrophysics Data System (ADS)

Jin, X.

2017-12-01

The Bayan Har Mountains (BHM) on northeastern Qinghai-Tibetan Plateau, Southwest China, is representative of elevational permafrost. Permafrost in the BHM is mostly warm (<-1°C) and mosaicked with seasonally frozen ground and taliks in discontinuous permafrost zones. Warming climate has led, is leading, and will lead to marked and profound permafrost changes. Consequently, permafrost changes significantly affect hydrology, ecology and engineered infrastructures in the source area of Yellow River. Due to the limited monitoring data, however, the permafrost in the BHM is poorly understood. Based on temperature measurements from boreholes established since 2010 and other historical archives, and field investigations since 2011, this study aims at analyzing spatiotemporal changes of permafrost and their associations with vegetation characteristics. Preliminary results show that: (1) It is evident that permafrost temperatures decrease with rising elevations. Mean annual ground temperature is generally above 0°C at elevations below 4,350 m a. s. l.; Above 4,520 m a. s. l. , permafrost temperature is lower than -0.5°C; (2) From 2011 to 2016, permafrost temperatures increased by 0.02-0.11°C at elevations below 4,400 m a. s. l. , but they decreased by 0.04°C above 4,520 m a. s. l.; (3) About 64 species of vegetation were found around the boreholes. Mesoxerophytes are the dominant species at elevations below 4,400 m a. s. l. in the areas of seasonally frozen ground, and; the cyperaceae dominate above 4,520 m a. s. l. in the permafrost zones. With rising elevations, aboveground biomass increases, but the species richness declines, maybe due to the variations in hydrothermal combinations and grazing. Under a warming and wetting climate, permafrost degradation, as evidenced by the reduction in areal extent of permafrost and thickening active layer, may result in declining or depletion of near-surface soil moisture due to the lowering permafrost and supra-permafrost water tables, and in shifting of alpine vegetation from meadows to steppes, and even in converting of alpine steppes to deserts in some areas due to the diminishing of water availability. Further study will focus on the quantitative relationships between frozen ground and alpine vegetation, and the symbiosis of the permafrost and alpine wetlands.

Ground-Water Quality Data in the Coachella Valley Study Unit, 2007: Results from the California GAMA Program

USGS Publications Warehouse

Goldrath, Dara A.; Wright, Michael T.; Belitz, Kenneth

2009-01-01

Ground-water quality in the approximately 820 square-mile Coachella Valley Study Unit (COA) was investigated during February and March 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of raw ground water used for public-water supplies within the Coachella Valley, and to facilitate statistically consistent comparisons of ground-water quality throughout California. Samples were collected from 35 wells in Riverside County. Nineteen of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Sixteen additional wells were sampled to evaluate changes in water chemistry along selected ground-water flow paths, examine land use effects on ground-water quality, and to collect water-quality data in areas where little exists. These wells were referred to as 'understanding wells'. The ground-water samples were analyzed for a large number of organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (uranium, tritium, carbon-14, and stable isotopes of hydrogen, oxygen, and boron), and dissolved noble gases (the last in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled ground water. A quality-control sample (blank, replicate, or matrix spike) was collected at approximately one quarter of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control information resulted in V-coding less than 0.1 percent of the data collected. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is supplied to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH) and thresholds established for aesthetic purposes (secondary maximum contaminant levels, SMCL-CA) by CDPH. Most constituents detected in ground-water samples were at concentrations below drinking-water thresholds. Volatile organic compounds, pesticides, and pesticide degradates were detected in less than one-third of the grid well samples collected. All VOC and pesticide concentrations measured were below health-based thresholds. Potential waste-water indicators were detected in less than half of the wells sampled, and no detections were above health-based thresholds. Perchlorate was detected in seven grid wells; concentrations from two wells were above the CDPH maximum contaminant level (MCL-CA). Most detections of trace elements in samples collected from COA Study Unit wells were below water-quality thresholds. Exceptions include five samples of arsenic that were above the USEPA maximum contaminant level (MCL-US), two detections of boron above the CDPH notification level (NL-CA), and two detections of mol

The Southampton-York Natural Scenes (SYNS) dataset: Statistics of surface attitude

PubMed Central

Adams, Wendy J.; Elder, James H.; Graf, Erich W.; Leyland, Julian; Lugtigheid, Arthur J.; Muryy, Alexander

2016-01-01

Recovering 3D scenes from 2D images is an under-constrained task; optimal estimation depends upon knowledge of the underlying scene statistics. Here we introduce the Southampton-York Natural Scenes dataset (SYNS: https://syns.soton.ac.uk), which provides comprehensive scene statistics useful for understanding biological vision and for improving machine vision systems. In order to capture the diversity of environments that humans encounter, scenes were surveyed at random locations within 25 indoor and outdoor categories. Each survey includes (i) spherical LiDAR range data (ii) high-dynamic range spherical imagery and (iii) a panorama of stereo image pairs. We envisage many uses for the dataset and present one example: an analysis of surface attitude statistics, conditioned on scene category and viewing elevation. Surface normals were estimated using a novel adaptive scale selection algorithm. Across categories, surface attitude below the horizon is dominated by the ground plane (0° tilt). Near the horizon, probability density is elevated at 90°/270° tilt due to vertical surfaces (trees, walls). Above the horizon, probability density is elevated near 0° slant due to overhead structure such as ceilings and leaf canopies. These structural regularities represent potentially useful prior assumptions for human and machine observers, and may predict human biases in perceived surface attitude. PMID:27782103

Estimating the probability of elevated nitrate (NO2+NO3-N) concentrations in ground water in the Columbia Basin Ground Water Management Area, Washington

USGS Publications Warehouse

Frans, Lonna M.

2000-01-01

Logistic regression was used to relate anthropogenic (man-made) and natural factors to the occurrence of elevated concentrations of nitrite plus nitrate as nitrogen in ground water in the Columbia Basin Ground Water Management Area, eastern Washington. Variables that were analyzed included well depth, depth of well casing, ground-water recharge rates, presence of canals, fertilizer application amounts, soils, surficial geology, and land-use types. The variables that best explain the occurrence of nitrate concentrations above 3 milligrams per liter in wells were the amount of fertilizer applied annually within a 2-kilometer radius of a well and the depth of the well casing; the variables that best explain the occurrence of nitrate above 10 milligrams per liter included the amount of fertilizer applied annually within a 3-kilometer radius of a well, the depth of the well casing, and the mean soil hydrologic group, which is a measure of soil infiltration rate. Based on the relations between these variables and elevated nitrate concentrations, models were developed using logistic regression that predict the probability that ground water will exceed a nitrate concentration of either 3 milligrams per liter or 10 milligrams per liter. Maps were produced that illustrate the predicted probability that ground-water nitrate concentrations will exceed 3 milligrams per liter or 10 milligrams per liter for wells cased to 78 feet below land surface (median casing depth) and the predicted depth to which wells would need to be cased in order to have an 80-percent probability of drawing water with a nitrate concentration below either 3 milligrams per liter or 10 milligrams per liter. Maps showing the predicted probability for the occurrence of elevated nitrate concentrations indicate that the irrigated agricultural regions are most at risk. The predicted depths to which wells need to be cased in order to have an 80-percent chance of obtaining low nitrate ground water exceed 600 feet in the irrigated agricultural regions, whereas wells in dryland agricultural areas generally need a casing in excess of 400 feet. The predicted depth to which wells need to be cased to have at least an 80-percent chance to draw water with a nitrate concentration less than 10 milligrams per liter generally did not exceed 800 feet, with a 200-foot casing depth typical of the majority of the area.

Recovery of Ground-Water Levels from 1988 to 2003 and Analysis of Effects of 2003 and Full-Allocation Withdrawals in Critical Area 2, Southern New Jersey

USGS Publications Warehouse

Spitz, Frederick J.; dePaul, Vincent T.

2008-01-01

Water levels in the Potomac-Raritan-Magothy aquifer system within Water Supply Critical Area 2 in the southern New Jersey Coastal Plain have recovered as a result of reductions in ground-water withdrawals initiated in the early 1990s. The Critical Area consists of the depleted zone and the threatened margin. The Potomac-Raritan-Magothy aquifer system consists of the Upper, Middle, and Lower aquifers. Generally, ground-water withdrawals from these aquifers declined 5 to 10 Mgal/d (million gallons per day) and water levels recovered 0 to 40 ft (foot) from 1988 to 2003. In order to reevaluate water-allocation restrictions in Critical Area 2 in response to changes in the ground-water-flow system and demands for additional water supply due to increased development, the New Jersey Department of Environmental Protection (NJDEP) needs information about the effects of changes in those allocations. Therefore, the U.S. Geological Survey (USGS), in cooperation with the NJDEP, used an existing ground-water-flow model of the New Jersey Coastal Plain to evaluate the effects of withdrawal alternatives on hydraulic heads in the Potomac-Raritan-Magothy aquifer system in Critical Area 2. The U.S. Geological Survey Regional Aquifer System Analysis model was used to simulate steady-state ground-water flow. Two withdrawal conditions were tested by using the model to evaluate hydraulic heads and differences in heads in these aquifers: 2003 withdrawals and full-allocation withdrawals (17.4 Mgal/d greater than 2003 withdrawals). Model results are presented using head maps and head-difference maps that compare 2003 to full-allocation withdrawals. Mandated hydrologic conditions for Critical Area protection are that the simulated -30-ft head contour not extend beyond the boundary of the depleted zone and (or) be at least 5 mi (miles) updip from the 250-mg/L (milligram per liter) isochlor in all three aquifers. Simulation results indicate that, for 2003 withdrawals, the simulated -30-ft head contour in all three aquifers is generally within the boundary of the depleted zone, except in the Lower aquifer in northern Camden and northwestern Burlington Counties, and is generally 1 to 10 mi downdip from the 250-mg/L isochlor. (Corresponding observed data indicate that the -30-ft water-level contour extends beyond the southwest boundary of the depleted zone in the Upper and Middle aquifers, and is generally 5 to 20 mi downdip from the 250-mg/L isochlor in all three aquifers.) The area in which heads are below -30 ft ranges from 389 mi2 (square miles) in the Middle aquifer to 427 mi2 in the Lower aquifer. For full-allocation withdrawals, the simulated -30-ft head contour extends beyond the boundary of the depleted zone in all three aquifers in northern Camden and northwestern Burlington Counties and in the Upper aquifer in Gloucester and Salem Counties, and is generally 5 to 15 mi downdip from the 250-mg/L isochlor. The area in which heads are below -30 ft ranges from 616 mi2 in the Upper aquifer to 813 mi2 in the Lower aquifer. These results and observed data indicate that any increase in withdrawals from 2003 values would likely cause heads in the three aquifers to decline below the minimum values mandated by the NJDEP for the Critical Area.

Hydrogeologic Setting, Ground-Water Flow, and Ground-Water Quality at the Langtree Peninsula Research Station, Iredell County, North Carolina, 2000-2005

USGS Publications Warehouse

Pippin, Charles G.; Chapman, Melinda J.; Huffman, Brad A.; Heller, Matthew J.; Schelgel, Melissa E.

2008-01-01

A 6-year intensive field study (2000-2005) of a complex, regolith-fractured bedrock ground-water system was conducted at the Langtree Peninsula research station on the Davidson College Lake Campus in Iredell County, North Carolina. This research station was constructed as part of the Piedmont and Mountains Resource Evaluation Program, a cooperative study being conducted by the North Carolina Department of Environment and Natural Resources and the U.S. Geological Survey. Results of the study characterize the distinction and interaction of a two-component ground-water system in a quartz diorite rock type. The Langtree Peninsula research station includes 17 monitoring wells and 12 piezometers, including 2 well transects along high to low topographic settings, drilled into separate parts of the ground-water-flow system. The location of the research station is representative of a metaigneous intermediate (composition) regional hydrogeologic unit. The primary rock type is mafic quartz diorite that has steeply dipping foliation. Primary and secondary foliations are present in the quartz diorite at the site, and both have an average strike of about N. 12 degree E. and dip about 60 degree in opposite directions to the southeast (primary) and the northwest (secondary). This rock is cut by granitic dikes (intrusions) ranging in thickness from 2 to 50 feet and having an average strike of N. 20 degree W. and an average dip of 66 degree to the southwest. Depth to consolidated bedrock is considered moderate to deep, ranging from about 24 to 76 feet below land surface. The transition zone was delineated and described in each corehole near the well clusters but had a highly variable thickness ranging from about 1 to 20 feet. Thickness of the regolith (23 to 68 feet) and the transition zone do not appear to be related to topographic setting. Delineated bedrock fractures are dominantly low angle (possibly stress relief), which were observed to be open to partially open at depths of as much as 479 feet below land surface. Well yields ranged from about 3 to 50 gallons per minute. The connection of fracture zones at depth was demonstrated in three bedrock wells during a 48-hour aquifer test, and drawdown curves were similar for all three wells. General findings of this study help characterize ground-water flow in the Piedmont and Mountains ground-water systems. Ground-water flow generally is from high to low topographic settings. Ground-water flow discharges toward a surface-water boundary (Lake Norman), and vertical hydraulic gradients generally are downward in recharge areas and upward in discharge areas. Dominant water types are calcium-bicarbonate and are similar in all three zones (regolith, transition zone, and bedrock) of the ground-water system. Results of continuous ground-water-quality monitoring indicate that ground-water recharge may occur seasonally over a period of several months or after heavy rainfall periods over a shorter period of a few to several weeks.

Below and above-ground carbon distribution along a rainfall gradient. A case of the Zambezi teak forests, Zambia

NASA Astrophysics Data System (ADS)

Ngoma, Justine; Moors, Eddy; Kruijt, Bart; Speer, James H.; Vinya, Royd; Chidumayo, Emmanuel N.; Leemans, Rik

2018-02-01

Understanding carbon (C) stocks or biomass in forests is important to examine how forests mitigate climate change. To estimate biomass in stems, branches and roots takes intensive fieldwork to uproot, cut and weigh the mass of each component. Different models or equations are also required. Our research focussed on the dry tropical Zambezi teak forests and we studied their structure at three sites following a rainfall gradient in Zambia. We sampled 3558 trees at 42 plots covering a combined area of 15ha. Using data from destructive tree samples, we developed mixed-species biomass models to estimate above ground biomass for small (<5 cm diameter at breast height (DBH, 1.3 m above-ground)) and large (≥5 cm DBH) trees involving 90 and 104 trees respectively, that belonged to 12 species. A below-ground biomass model was developed from seven trees of three species (16-44 cm DBH) whose complete root systems were excavated. Three stump models were also derived from these uprooted trees. Finally, we determined the C fractions from 194 trees that belonged to 12 species. The analysis revealed that DBH was the only predictor that significantly correlated to both above-ground and below-ground biomass. We found a mean root-to-shoot ratio of 0.38:0.62. The C fraction in leaves ranged from 39% to 42%, while it varied between 41% and 46% in wood. The C fraction was highest at the Kabompo site that received the highest rainfall, and lowest at the intermediate Namwala site. The C stocks varied between 15 and 36 ton C ha-1 and these stocks where highest at the wetter Kabompo site and lowest at the drier Sesheke site. Our results indicate that the projected future rainfall decrease for southern Africa, will likely reduce the C storage potential of the Zambezi teak forests, thereby adversely affecting their mitigating role in climate change.

Ferro- and antiferro-magnetism in (Np, Pu)BC

NASA Astrophysics Data System (ADS)

Klimczuk, T.; Shick, A. B.; Kozub, A. L.; Griveau, J.-C.; Colineau, E.; Falmbigl, M.; Wastin, F.; Rogl, P.

2015-04-01

Two new transuranium metal boron carbides, NpBC and PuBC, have been synthesized. Rietveld refinements of powder XRD patterns of {Np,Pu}BC confirmed in both cases isotypism with the structure type of UBC. Temperature dependent magnetic susceptibility data reveal antiferromagnetic ordering for PuBC below TN = 44 K, whereas ferromagnetic ordering was found for NpBC below TC = 61 K. Heat capacity measurements prove the bulk character of the observed magnetic transition for both compounds. The total energy electronic band structure calculations support formation of the ferromagnetic ground state for NpBC and the antiferromagnetic ground state for PuBC.

5-Year Update Environmental Assessment for CV-22 Beddown

DTIC Science & Technology

2007-02-01

supersonic flight. Activities do not include intentional fuel dumping below 6,000 feet. No new facilities or utilities will be necessary to support IOT&E...the ground, climb a ladder from the ground in to the aircraft, or ride the rescue hoist from the ground in to the aircraft. Once forces are secured...Crew Chief and specialists in the fields of Integrated Avionics, Propulsion, Hydraulics , and Electro- Environmental maintenance. The majority of the

Gaze transfer in remote cooperation: is it always helpful to see what your partner is attending to?

PubMed

Müller, Romy; Helmert, Jens R; Pannasch, Sebastian; Velichkovsky, Boris M

2013-01-01

Establishing common ground in remote cooperation is challenging because nonverbal means of ambiguity resolution are limited. In such settings, information about a partner's gaze can support cooperative performance, but it is not yet clear whether and to what extent the abundance of information reflected in gaze comes at a cost. Specifically, in tasks that mainly rely on spatial referencing, gaze transfer might be distracting and leave the partner uncertain about the meaning of the gaze cursor. To examine this question, we let pairs of participants perform a joint puzzle task. One partner knew the solution and instructed the other partner's actions by (1) gaze, (2) speech, (3) gaze and speech, or (4) mouse and speech. Based on these instructions, the acting partner moved the pieces under conditions of high or low autonomy. Performance was better when using either gaze or mouse transfer compared to speech alone. However, in contrast to the mouse, gaze transfer induced uncertainty, evidenced in delayed responses to the cursor. Also, participants tried to resolve ambiguities by engaging in more verbal effort, formulating more explicit object descriptions and fewer deictic references. Thus, gaze transfer seems to increase uncertainty and ambiguity, thereby complicating grounding in this spatial referencing task. The results highlight the importance of closely examining task characteristics when considering gaze transfer as a means of support.

Use of Thermal Data to Estimate Infiltration in Pagany Wash Associated with the winter of 1997-1998 El Nino Precipitation, Yucca Mountain, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

G.D. LeCain; N. lu; M. Kurzmack

Temperature and air-pressure monitoring in a vertical borehole located in Pagany Wash, a normally dry stream-carved channel northeast of Yucca Mountain, Nevada, indicated that the annual temperature wave was measurable to a depth of 11.1 m. Temperature depressions were measured at depths of 3.1, 6.1, 9.2, and 11.1 m below ground surface. The temperature depressions were interpreted to be the result of infiltration associated with the 1997-1998 El Nino precipitation. A pressure differential, of approximately 2 kiloPascals, between stations located 11.1 and 24.5 m below ground surface was interpreted to be the result of compressed air ahead of the wettingmore » front. The pressure differences between stations indicated that the wetting front migrated deeper than 35.2 m and that the Yucca Mountain Tuff retarded the downward movement of the wetting front. An analytical method indicated that the infiltration flux through the Pagany Wash alluvium due to the 1997-1998 El Nino precipitation was approximately 940 mm. A one-dimensional numerical model indicated that the infiltration flux was approximately 1000 mm. Sensitivity analysis indicated that the potential temperature decrease due to conduction was minimal and that cooler surface temperatures could not account for the measured subsurface temperature depressions.« less

The Transcendental Phases of Learning

ERIC Educational Resources Information Center

Vandenberg, Donald

2002-01-01

The basic task of educational theory is to ground education in the being of children and youth. Education, however, is a very broad domain, consisting of four major problem areas: (1) the nature and aim of education; (2) the organisation of instruction and school policy; (3) the design and content of the curriculum; and (4) the teaching and…

Data Acquisition System(DAS) Sustaining Engineering

NASA Technical Reports Server (NTRS)

1998-01-01

This paper presents general information describing the Data Acquisition System contract, a summary of objectives, tasks performed and completed. The hardware deliverables which are comprised of: 1) Two ground DAS units; 2) Two flight DAS units; 3) Logistic spares; and 4) Shipping containers are described. Also included are the data requirements and scope of the contract.

Spatial distribution and temporal variations of occurrence frequency of lightning whistlers observed by VLF/WBA onboard Akebono

NASA Astrophysics Data System (ADS)

Oike, Yuta; Kasahara, Yoshiya; Goto, Yoshitaka

2014-09-01

We statistically analyzed lightning whistlers detected from the analog waveform data below 15 kHz observed by the VLF instruments onboard Akebono. We examined the large amount of data obtained at Uchinoura Space Center in Japan for 22 years from 1989 to 2010. The lightning whistlers were mainly observed inside the L shell region below 2. Seasonal dependence of the occurrence frequency of lightning whistlers has two peaks around July to August and December to January. As lightning is most active in summer, in general, these two peaks correspond to summer in the Northern and Southern Hemispheres, respectively. Diurnal variation of the occurrence frequency showed that lightning whistlers begin to increase in the early evening and remain at a high-occurrence level through the night with a peak around 21 in magnetic local time (MLT). This peak shifts toward nightside compared with lightning activity, which begins to rise around noon and peaks in the late afternoon. This trend is supposed to be caused by attenuation of VLF wave in the ionosphere in the daytime. Comparison study with the ground-based observation revealed consistent results, except that the peak of the ground-based observation appeared after midnight while our measurements obtained by Akebono was around 21 in MLT. This difference is explained qualitatively in terms that lightning whistlers measured at the ground station passed through the ionosphere twice above both source region and the ground station. These facts provide an important clue to evaluate quantitatively the absorption effect of lightning whistler in the ionosphere.

EPN Chemical ecology and new techniques for below ground sampling and analyses of volatile semiochemicals

USDA-ARS?s Scientific Manuscript database

It is well established that herbivory induced plant volatiles (HIPVs) attract natural enemies of the herbivores. Utilizing this plant response has become a fundamental part of above ground IPM programs. We now know that also roots can release HIPVs and that these compounds attract beneficial organis...

Comparing two forms of a childhood perspective-taking measure using CFA and IRT.

PubMed

Carey, Jasmine M; Cassels, Tracy G

2013-09-01

Deficits in perspective-taking ability have been linked to social problems associated with disorders such as autism spectrum disorders (ASD) and conduct disorder. Even subtle deficits in perspective-taking are related to social adjustment and moral development. A common measure of perspective-taking abilities in children is the "Reading the Mind in the Eyes Task" ("Eyes task"; Baron-Cohen, Wheelwright, Spong, Scahill, & Lawson, 2001). The Eyes task was primarily developed for use in identifying individuals with ASDs, while its function with nonclinical populations has not been clearly addressed. Additionally, it is unknown whether the Eyes task can be used to measure specific deficits or abilities in the cognitive or emotional components of perspective-taking. In this article we assessed the structure and function of the Eyes task and an open ended or generative format of the same task (Generative Eyes Task; GET) found to measure emotional perspective-taking specifically. Confirmatory factor analyses found the traditional Eyes task to have the assumed single factor structure, while the GET has a clear 2-factor structure corresponding to emotionally valenced or neutral items. The Eyes task and the GET were also compared using item response theory. The Eyes task provided the most measurement accuracy at 2 standard deviations below the mean making it most accurate for populations with severe deficits, while the GET was most accurate at the mean level of perspective-taking. Based on these analyses, we conclude that the GET is more appropriate for use in nonclinical populations and when emotional perspective-taking abilities are of interest.

Ground water in carbonate rocks and regolith in the Fairview area, Tennessee

USGS Publications Warehouse

Burchett, C.R.; Zurawski, Ann; Sparkes, A.K.; Hollyday, E.F.

1983-01-01

Fourteen test wells drilled in the Fairview area, Tennessee, produce from 3 to 100 gallons per minute and have an average yield of 32 gallons per minute, measured while blowing water from the wells with compressed air. In comparison, the average yield of supply wells reported by drillers is 13 gallons per minute. Specific capacities for three of the test wells ranged from 0.3 to 0.6 gallons per minute per foot of drawdown after 8 hours of pumping at 20 to 47 gallons per minute. Two test wells had specific capacities of 1.1 and 0.4 gallons per foot of drawdown after 72 hours of pumping at 55 and 43 gallons per minute. The mineral content of ground water increases greatly below a gypsum horizon approximately 100 feet below the top of the Fort Payne Formation. Ground water above the gypsum horizon, however, meets the standards for finished drinking water. (USGS)

Experimental analysis of direct-expansion ground-coupled heat pump systems

NASA Astrophysics Data System (ADS)

Mei, V. C.; Baxter, V. D.

1991-09-01

Direct-expansion ground-coil-coupled (DXGC) heat pump systems have certain energy efficiency advantages over conventional ground-coupled heat pump (GCHP) systems. Principal among these advantages are that the secondary heat transfer fluid heat exchanger and circulating pump are eliminated. While the DXGC concept can produce higher efficiencies, it also produces more system design and environmental problems (e.g., compressor starting, oil return, possible ground pollution, and more refrigerant charging). Furthermore, general design guidelines for DXGC systems are not well documented. A two-pronged approach was adopted for this study: (1) a literature survey, and (2) a laboratory study of a DXGC heat pump system with R-22 as the refrigerant, for both heating and cooling mode tests done in parallel and series tube connections. The results of each task are described in this paper. A set of general design guidelines was derived from the test results and is also presented.

Intelligent systems for KSC ground processing

NASA Technical Reports Server (NTRS)

Heard, Astrid E.

1992-01-01

The ground processing and launch of Shuttle vehicles and their payloads is the primary task of Kennedy Space Center. It is a process which is largely manual and contains little inherent automation. Business is conducted today much as it was during previous NASA programs such as Apollo. In light of new programs and decreasing budgets, NASA must find more cost effective ways in which to do business while retaining the quality and safety of activities. Advanced technologies including artificial intelligence could cut manpower and processing time. This paper is an overview of the research and development in Al technology at KSC with descriptions of the systems which have been implemented, as well as a few under development which are promising additions to ground processing software. Projects discussed cover many facets of ground processing activities, including computer sustaining engineering, subsystem monitor and diagnosis tools and launch team assistants. The deployed Al applications have proven an effectiveness which has helped to demonstrate the benefits of utilizing intelligent software in the ground processing task.

Quantifying above- and below-ground growth responses of the western Australian oil mallee, Eucalyptus kochii subsp. plenissima, to contrasting decapitation regimes.

PubMed

Wildy, Dan T; Pate, John S

2002-08-01

Resprouting in the oil mallee, Eucalyptus kochii Maiden & Blakely subsp. plenissima Gardner (Brooker), involves generation of new shoots from preformed meristematic foci on the lignotuber. Numbers of such foci escalated from 200 per lignotuber in trees aged 1 year to 3,000 on 4- to 5-year-old trees. Removal of shoot biomass by decapitation 5 cm above ground in summer (February) or spring (October) resulted in initiation of 140-170 new shoots, but approx. 400 shoots were induced to form if crops of new shoots were successively removed until sprouting ceased and rootstocks senesced. Initially, the new shoot biomass of regenerating coppices increased slowly and the root biomass failed to increase appreciably until 1.7-2.5 years after cutting. Newly cut trees showed loss of fine root biomass, and structural roots failed to secondarily thicken to the extent shown by uncut trees. After 2 years, the biomass of shoots of coppiced plants was only one-third that of uncut control trees and shoot:root dry mass ratios of coppiced plants were still low (1.5-2.0) compared with those of the controls (average ratio of 3.1). Spring cutting promoted quicker and greater biomass recovery than summer cutting. Starch in below-ground biomass fell quickly following decapitation and remained low for a 12-18 month period. Utilization of starch reserves in naturally regenerating coppices was estimated to provide only a small proportion of the dry matter accumulated in new shoots. Results are discussed in relation to their impact on coppicing ability of the species under natural conditions or when successively coppiced for shoot biomass production.

Syndecan-1 and Metastasis Dormancy

DTIC Science & Technology

2015-09-01

Sdc1 WT vs Sdc1 KO mice (p = 0.36). - 5 - Major Task 2: Optimize 3D lung microenvironment assay Subtask 1: Transduce HMVEC-L with E4ORF1 and mCherry...micro-channel devices (see below) but have not yet transduced them with E4ORF1 nor labeled them. If we succeed in generating defined vascular

Ground-water quality, water year 1995, and statistical analysis of ground-water-quality data, water years 1994-95, at the Chromic Acid Pit site, US Army Air Defense Artillery Center and Fort Bliss, El Paso, Texas

USGS Publications Warehouse

Abeyta, Cynthia G.; Roybal, R.G.

1996-01-01

The Chromic Acid Pit site is an inactive waste disposal site that is regulated by the Resource Conservation and Recovery Act of 1976. The 2.2-cubic-yard cement-lined pit was operated from 1980 to 1983 by a contractor to the U.S. Army Air Defense Artillery Center and Fort Bliss. The pit, located on the Fort Bliss military reservation in El Paso, Texas, was used for disposal and evaporation of chromic acid waste generated from chrome plating operations. The site was closed in 1989, and the Texas Natural Resources Conservation Commission issued permit number HW-50296 (U.S. Environmental Protection Agency number TX4213720101), which approved and implemented post-closure care for the Chromic Acid Pit site. In accordance with an approved post-closure plan, the U.S. Geological Survey is cooperating with the U.S. Army in monitoring and evaluating ground-water quality at the site. One upgradient ground-water monitoring well (MW1) and two downgradient ground-water monitoring wells (MW2 and MW3), installed adjacent to the chromic acid pit, are monitored on a quarterly basis. Ground-water sampling of these wells by the U.S. Geological Survey began in December 1993. The ground-water level, measured in a production well located approximately 1,700 feet southeast of the Chromic Acid Pit site, has declined about 29.43 feet from 1982 to 1995. Depth to water at the Chromic Acid Pit site in September 1995 was 284.2 to 286.5 feet below land surface; ground-water flow at the water table is assumed to be toward the southeast. Ground-water samples collected from monitoring wells at the Chromic Acid Pit site during water year 1995 contained dissolved- solids concentrations of 481 to 516 milligrams per liter. Total chromium concentrations detected above the laboratory reporting limit ranged from 0.0061 to 0.030 milligram per liter; dissolved chromium concentrations ranged from 0.0040 to 0.010 milligram per liter. Nitrate as nitrogen concentrations ranged from 2.1 to 2.8 milligrams per liter; nitrite plus nitrate as nitrogen concentrations ranged from 2.4 to 3.2 milligrams per liter. Water samples from wells MW1 and MW2 were analyzed for volatile organic compounds for the first quarter; no confirmed volatile organic compounds were detected above laboratory reporting limits. Detected chemical concentrations in water from the chromic acid pit monitoring wells during the four sampling periods were below U.S. Environmental Protection Agency-established maximum contaminant levels for public drinking-water supplies. Overall, water-quality characteristics of water from the chromic acid pit ground-water monitoring wells are similar to those of other wells in the surrounding area. Statistical analyses were performed on 56 of the chemical constituents analyzed for in ground water from the chromic acid pit monitoring wells. Concentrations of chloride, fluoride, sulfate, and potassium were significantly less in water from one or both downgradient wells than in water from the upgradient well. Concentrations of nitrate as nitrogen, nitrite plus nitrate as nitrogen, and dissolved solids were significantly greater in water from the downgradient wells than in water from the upgradient well. Concentrations of nitrate as nitrogen, chloride, and potassium were significantly different in water from the two downgradient wells. Statistical analysis of chemical constituents in water from the chromic acid pit monitoring wells did not appear to indicate a release of hazardous chemicals from the chromic acid pit. There was no indication of ground-water contamination in either downgradient well.

Carbon transfer from photosynthesis to below ground fine root/hyphae respiration in Quercus serrata using stable carbon isotope pulse labeling

NASA Astrophysics Data System (ADS)

Dannoura, M.; Kominami, Y.; Takanashi, S.; Takahashi, K.

2013-12-01

Studying carbon allocation in trees is a key to better understand belowground carbon cycle and its response to climate change. Tracing 13C in tree and soil compartments after pulse labeling is one of powerful tool to study the fate of carbon in forest ecosystems. This experiment was conducted in Yamashiro experimental forest, Kyoto, Japan. Annual mean temperature and precipitation from 1994 to 2009 are 15.5 ° C and 1,388 mm respectively. The branch pulse labeling were done 7 times in 2011 using same branch of Quercus serrata (H:11.7 m, DBH; 33.7 cm) to see seasonal variations of carbon velocity. Whole crown labeling of Quercus serrata (H:9 m, DBH; 13.7 cm) was done in 2012 to study carbon allocation and to especially focus on belowground carbon flux until to the hyphae respiration. Pure 13CO2 (99.9%) was injected to the labeling chamber which was set to branch or crown. Then, after one hour of branch labeling and 3.5 hour for crown labeling, the chamber was opened. Trunk respiration chambers, fine root chambers and hyphae chambers were set to the target tree to trace labeled carbon in the CO2 efflux. 41 μm mesh was used to exclude ingrowth of roots into hyphae chambers. The results show that the velocity of carbon through the tree varied seasonally, with higher velocity in summer than autumn, averaging 0.47 m h-1. Half-lives of labeled carbon in autotrophic respiration were similar above and below ground during the growing season, but they were twice longer in trunk than in root in autumn. From the whole crown labeling done end of growing season, the 13CO2 signal was observed 25 hours after labeling in trunk chamber and 34-37.7 hours after labeling in fine root and hyphae respiration almost simultaneously. Half-lives of 13 was longer in trunk than below ground. Trunk respiration was still using labelled carbon during winter suggesting that winter trunk respiration is partly fueled by carbon stored in the trunk at the end of the growing season.

[Development of fixed-base full task space flight training simulator].

PubMed

Xue, Liang; Chen, Shan-quang; Chang, Tian-chun; Yang, Hong; Chao, Jian-gang; Li, Zhi-peng

2003-01-01

Fixed-base full task flight training simulator is a very critical and important integrated training facility. It is mostly used in training of integrated skills and tasks, such as running the flight program of manned space flight, dealing with faults, operating and controlling spacecraft flight, communicating information between spacecraft and ground. This simulator was made up of several subentries including spacecraft simulation, simulating cabin, sight image, acoustics, main controlling computer, instructor and assistant support. It has implemented many simulation functions, such as spacecraft environment, spacecraft movement, communicating information between spacecraft and ground, typical faults, manual control and operating training, training control, training monitor, training database management, training data recording, system detecting and so on.

A DNA barcode library for ground beetles (Insecta, Coleoptera, Carabidae) of Germany: The genus Bembidion Latreille, 1802 and allied taxa

PubMed Central

Raupach, Michael J.; Hannig, Karsten; Morinière, Jérome; Hendrich, Lars

2016-01-01

Abstract As molecular identification method, DNA barcoding based on partial cytochrome c oxidase subunit 1 (COI) sequences has been proven to be a useful tool for species determination in many insect taxa including ground beetles. In this study we tested the effectiveness of DNA barcodes to discriminate species of the ground beetle genus Bembidion and some closely related taxa of Germany. DNA barcodes were obtained from 819 individuals and 78 species, including sequences from previous studies as well as more than 300 new generated DNA barcodes. We found a 1:1 correspondence between BIN and traditionally recognized species for 69 species (89%). Low interspecific distances with maximum pairwise K2P values below 2.2% were found for three species pairs, including two species pairs with haplotype sharing (Bembidion atrocaeruleum/Bembidion varicolor and Bembidion guttula/Bembidion mannerheimii). In contrast to this, deep intraspecific sequence divergences with distinct lineages were revealed for two species (Bembidion geniculatum/Ocys harpaloides). Our study emphasizes the use of DNA barcodes for the identification of the analyzed ground beetles species and represents an important step in building-up a comprehensive barcode library for the Carabidae in Germany and Central Europe as well. PMID:27408547

The Association for Behavior Analysis International Position Statement on Restraint and Seclusion

ERIC Educational Resources Information Center

Vollmer, Timothy R.; Hagopian, Louis P.; Bailey, Jon S.; Dorsey, Michael F.; Hanley, Gregory P.; Lennox, David; Riordan, Mary M.; Spreat, Scott

2011-01-01

A task force authorized by the Executive Council of the Association for Behavior Analysis International (ABAI) generated the statement below concerning the techniques called "restraint" and "seclusion." Members of the task force independently reviewed the scientific literature concerning restraint and seclusion and agreed unanimously to the…

Below-ground biotic interactions moderated the postglacial range dynamics of trees.

PubMed

Pither, Jason; Pickles, Brian J; Simard, Suzanne W; Ordonez, Alejandro; Williams, John W

2018-05-17

Tree range shifts during geohistorical global change events provide a useful real-world model for how future changes in forest biomes may proceed. In North America, during the last deglaciation, the distributions of tree taxa varied significantly as regards the rate and direction of their responses for reasons that remain unclear. Local-scale processes such as establishment, growth, and resilience to environmental stress ultimately influence range dynamics. Despite the fact that interactions between trees and soil biota are known to influence local-scale processes profoundly, evidence linking below-ground interactions to distribution dynamics remains scarce. We evaluated climate velocity and plant traits related to dispersal, environmental tolerance and below-ground symbioses, as potential predictors of the geohistorical rates of expansion and contraction of the core distributions of tree genera between 16 and 7 ka bp. The receptivity of host genera towards ectomycorrhizal fungi was strongly supported as a positive predictor of poleward rates of distribution expansion, and seed mass was supported as a negative predictor. Climate velocity gained support as a positive predictor of rates of distribution contraction, but not expansion. Our findings indicate that understanding how tree distributions, and thus forest ecosystems, respond to climate change requires the simultaneous consideration of traits, biotic interactions and abiotic forcing. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Reliability of Wearable Inertial Measurement Units to Measure Physical Activity in Team Handball.

PubMed

Luteberget, Live S; Holme, Benjamin R; Spencer, Matt

2018-04-01

To assess the reliability and sensitivity of commercially available inertial measurement units to measure physical activity in team handball. Twenty-two handball players were instrumented with 2 inertial measurement units (OptimEye S5; Catapult Sports, Melbourne, Australia) taped together. They participated in either a laboratory assessment (n = 10) consisting of 7 team handball-specific tasks or field assessment (n = 12) conducted in 12 training sessions. Variables, including PlayerLoad™ and inertial movement analysis (IMA) magnitude and counts, were extracted from the manufacturers' software. IMA counts were divided into intensity bands of low (1.5-2.5 m·s -1 ), medium (2.5-3.5 m·s -1 ), high (>3.5 m·s -1 ), medium/high (>2.5 m·s -1 ), and total (>1.5 m·s -1 ). Reliability between devices and sensitivity was established using coefficient of variation (CV) and smallest worthwhile difference (SWD). Laboratory assessment: IMA magnitude showed a good reliability (CV = 3.1%) in well-controlled tasks. CV increased (4.4-6.7%) in more-complex tasks. Field assessment: Total IMA counts (CV = 1.8% and SWD = 2.5%), PlayerLoad (CV = 0.9% and SWD = 2.1%), and their associated variables (CV = 0.4-1.7%) showed a good reliability, well below the SWD. However, the CV of IMA increased when categorized into intensity bands (2.9-5.6%). The reliability of IMA counts was good when data were displayed as total, high, or medium/high counts. A good reliability for PlayerLoad and associated variables was evident. The CV of the previously mentioned variables was well below the SWD, suggesting that OptimEye's inertial measurement unit and its software are sensitive for use in team handball.

Measurement of high-energy neutron flux above ground utilizing a spallation based multiplicity technique

DOE PAGES

Roecker, Caleb; Bernstein, Adam; Marleau, Peter; ...

2016-11-14

Cosmogenic high-energy neutrons are a ubiquitous, difficult to shield, poorly measured background. Above ground the high-energy neutron energy-dependent flux has been measured, with significantly varying results. Below ground, high-energy neutron fluxes are largely unmeasured. Here we present a reconstruction algorithm to unfold the incident neutron energy-dependent flux measured using the Multiplicity and Recoil Spectrometer (MARS), simulated test cases to verify the algorithm, and provide a new measurement of the above ground high-energy neutron energy-dependent flux with a detailed systematic uncertainty analysis. Uncertainty estimates are provided based upon the measurement statistics, the incident angular distribution, the surrounding environment of the Montemore » Carlo model, and the MARS triggering efficiency. Quantified systematic uncertainty is dominated by the assumed incident neutron angular distribution and surrounding environment of the Monte Carlo model. The energy-dependent neutron flux between 90 MeV and 400 MeV is reported. Between 90 MeV and 250 MeV the MARS results are comparable to previous Bonner sphere measurements. Over the total energy regime measured, the MARS result are located within the span of previous measurements. Lastly, these results demonstrate the feasibility of future below ground measurements with MARS.« less

Measurement of high-energy neutron flux above ground utilizing a spallation based multiplicity technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roecker, Caleb; Bernstein, Adam; Marleau, Peter

Cosmogenic high-energy neutrons are a ubiquitous, difficult to shield, poorly measured background. Above ground the high-energy neutron energy-dependent flux has been measured, with significantly varying results. Below ground, high-energy neutron fluxes are largely unmeasured. Here we present a reconstruction algorithm to unfold the incident neutron energy-dependent flux measured using the Multiplicity and Recoil Spectrometer (MARS), simulated test cases to verify the algorithm, and provide a new measurement of the above ground high-energy neutron energy-dependent flux with a detailed systematic uncertainty analysis. Uncertainty estimates are provided based upon the measurement statistics, the incident angular distribution, the surrounding environment of the Montemore » Carlo model, and the MARS triggering efficiency. Quantified systematic uncertainty is dominated by the assumed incident neutron angular distribution and surrounding environment of the Monte Carlo model. The energy-dependent neutron flux between 90 MeV and 400 MeV is reported. Between 90 MeV and 250 MeV the MARS results are comparable to previous Bonner sphere measurements. Over the total energy regime measured, the MARS result are located within the span of previous measurements. Lastly, these results demonstrate the feasibility of future below ground measurements with MARS.« less

Nanoparticle-based measurements of pH and O2 dynamics in the rhizosphere of Zostera marina L.: effects of temperature elevation and light-dark transitions.

PubMed

Elgetti Brodersen, Kasper; Koren, Klaus; Lichtenberg, Mads; Kühl, Michael

2016-07-01

Seagrasses can modulate the geochemical conditions in their immediate rhizosphere through the release of chemical compounds from their below-ground tissue. This is a vital chemical defence mechanism, whereby the plants detoxify the surrounding sediment. Using novel nanoparticle-based optical O2 and pH sensors incorporated in reduced and transparent artificial sediment, we investigated the spatio-temporal dynamics of pH and O2 within the entire rhizosphere of Zostera marina L. during experimental manipulations of light and temperature. We combined such measurements with O2 microsensor measurements of the photosynthetic productivity and respiration of seagrass leaves. We found pronounced pH and O2 microheterogeneity within the immediate rhizosphere of Z. marina, with higher below-ground tissue oxidation capability and rhizoplane pH levels during both light exposure of the leaf canopy and elevated temperature, where the temperature-mediated stimuli of biogeochemical processes seemed to predominate. Low rhizosphere pH microenvironments appeared to correlate with plant-derived oxic microzones stimulating local sulphide oxidation and thus driving local proton generation, although the rhizoplane pH levels generally where much higher than the bulk sediment pH. Our data show that Z. marina can actively alter its rhizosphere pH microenvironment alleviating the local H2 S toxicity and enhancing nutrient availability in the adjacent sediment via geochemical speciation shift. © 2016 John Wiley & Sons Ltd.

Influence of strike object grounding on close lightning electric fields

NASA Astrophysics Data System (ADS)

Baba, Yoshihiro; Rakov, Vladimir A.

2008-06-01

Using the finite difference time domain (FDTD) method, we have calculated vertical electric field Ez, horizontal (radial) electric field Eh, and azimuthal magnetic field Hϕ produced on the ground surface by lightning strikes to 160-m- and a 553-m-high conical strike objects representing the Peissenberg tower (Germany) and the CN Tower (Canada), respectively. The fields were computed for a typical subsequent stroke at distances d' from the bottom of the object ranging from 5 to 100 m for the 160-m tower and from 10 to 300 m for the 553-m tower. Grounding of the 160-m object was assumed to be accomplished by its underground basement represented by a 10-m-radius and 8-m-long perfectly conducting cylinder with or without a reference ground plane located 2 m below. The reference ground plane simulates, to some extent, a higher-conducting ground layer that is expected to exist below the water table. The configuration without reference ground plane actually means that this plane is present, but is located at an infinitely large depth. Grounding of the 553-m object was modeled in a similar manner but in the absence of reference ground plane only. In all cases considered, waveforms of Eh and Hϕ are not much influenced by the presence of strike object, while waveforms of Ez are. Waveforms of Ez are essentially unipolar (as they are in the absence of strike object) when the ground conductivity σ is 10 mS/m (the equivalent transient grounding impedance is several ohms) or greater. Thus, for the CN Tower, for which σ ≥ 10 mS/m, the occurrence of Ez polarity change is highly unlikely. For the 160-m tower and for σ = 1 and 0.1 mS/m, waveforms of Ez become bipolar (exhibit polarity change) at d' ≤ 10 m and d' ≤ 50 m, respectively, regardless of the presence of the reference ground plane. The corresponding equivalent transient grounding impedances are about 30 and 50 Ω in the absence of the reference ground plane and smaller than 10 Ω in the presence of the reference ground plane. The source of opposite polarity Ez is the potential rise at the object base (at the air/ground interface) relative to the reference ground plane. For a given grounding electrode geometry, the strength of this source increases with decreasing σ, provided that the grounding impedance is linear. Potential rises at the strike object base for σ = 1 and 0.1 mS/m are some hundreds of kilovolts, which is sufficient to produce electrical breakdown from relatively sharp edges of the basement over a distance of several meters (or more) along the ground surface. The resultant ground surface arcs will serve to reduce the equivalent grounding impedance and, hence, potential rise. Therefore, the polarity change of Ez near the Peissenberg tower, for which σ is probably about 1 mS/m, should be a rare phenomenon, if it occurs at all. The equivalent transient grounding impedance of the cylindrical basement is similar to that of a hemispherical grounding electrode of the same radius. For the 160-m tower and for hemispherical grounding electrode, the transient grounding impedance is higher than its dc grounding resistance for σ = 10 and 1 mS/m, but lower for σ = 0.1 mS/m. For the 553-m tower, the transient grounding impedance of hemispherical electrode is equal to or larger than its dc resistance for all values of σ considered.

A Methodology to Assess the Benefit of Operational or Tactic Adjustments to Reduce Marine Corps Fuel Consumption

DTIC Science & Technology

2015-12-01

simulation M777A2 howitzer MAGTF Marine Air-Ground Task Force MANA Map Aware Non-Uniform Automata MCWL Marine Corps Warfighting Lab MEB Marine...met. The project developed a Map Aware Non-Uniform Automata (MANA) model for each SPMAGTF size. The MANA models simulated the maneuver and direct

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zarkevich, Nikolai A.; Johnson, Duane D.

Cubic B2 FeRh exhibits a metamagnetic transition [(111) antiferromagnet (AFM) to ferromagnet (FM)] around 353 K and remains structurally stable at higher temperatures. However, the calculated zero-Kelvin phonons of AFM FeRh exhibit imaginary modes at M points in the Brillouin zone, indicating a premartensitic instability, which is a precursor to a martensitic transformation at low temperatures. Combining electronic-structure calculations with ab initio molecular dynamics, conjugate gradient relaxation, and the solid-state nudged-elastic band methods, we predict that AFM B2 FeRh becomes unstable at ambient pressure and transforms without a barrier to an AFM(111) orthorhombic (martensitic) ground state below 90±10K. In conclusion,more » we also consider competing structures, in particular, a tetragonal AFM(100) phase that is not the global ground state, as proposed, but a constrained solution.« less

Cardiovascular fitness and executive control during task-switching: an ERP study.

PubMed

Scisco, Jenna L; Leynes, P Andrew; Kang, Jie

2008-07-01

Cardiovascular fitness recently has been linked to executive control function in older adults. The present study examined the relationship between cardiovascular fitness and executive control in young adults using event-related potentials (ERPs). Participants completed a two-part experiment. In part one, a graded exercise test (GXT) was administered using a cycle ergometer to obtain VO(2)max, a measure of maximal oxygen uptake. High-fit participants had VO(2)max measures at or above the 70th percentile based on age and sex, and low-fit participants had VO(2)max measures at or below the 30th percentile. In part two, a task-switching paradigm was used to investigate executive control. Task-switching trials produced slower response times and greater amplitude for both the P3a and P3b components of the ERP relative to a non-switch trial block. No ERP components varied as a function of fitness group. These findings, combined with results from previous research, suggest that the relationship between greater cardiovascular fitness and better cognitive function emerges after early adulthood.

Vegetative Regeneration Capacities of Five Ornamental Plant Invaders After Shredding

NASA Astrophysics Data System (ADS)

Monty, Arnaud; Eugène, Marie; Mahy, Grégory

2015-02-01

Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk.

Vegetative regeneration capacities of five ornamental plant invaders after shredding.

PubMed

Monty, Arnaud; Eugène, Marie; Mahy, Grégory

2015-02-01

Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk.

Competing magnetic ground states and their coupling to the crystal lattice in CuFe2Ge2

NASA Astrophysics Data System (ADS)

May, Andrew; Calder, Stuart; Parker, David; Sales, Brian; McGuire, Michael

CuFe2Ge2 has been identified as a system with competing magnetic ground states that are strongly coupled to the crystal lattice and easily manipulated by temperature or applied magnetic field. Powder neutron diffraction data reveal the emergence of antiferromagnetic (AFM) order near TN = 175 K, as well as a transition into an incommensurate AFM spin structure below approximately 125 K. Together with refined moments of approximately 1 Bohr magneton per iron, the incommensurate structure supports an itinerant picture of magnetism in CuFe2Ge2, which is consistent with theoretical calculations. Bulk magnetization measurements suggest that the spin structures are easily manipulated with an applied field, which further demonstrates the near-degeneracy of different magnetic configurations. Interestingly, the thermal expansion is found to be very anisotropic, and the c lattice parameter has anomalous temperature dependence near TN. These results show that the ground state of CuFe2Ge2 is easily manipulated by external forces, making it a potential parent compound for a rich phase diagram of emergent phenomena. Research supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division and Scientific User Facilities Division.

Land-use type and intensity differentially filter traits in above- and below-ground arthropod communities.

PubMed

Birkhofer, Klaus; Gossner, Martin M; Diekötter, Tim; Drees, Claudia; Ferlian, Olga; Maraun, Mark; Scheu, Stefan; Weisser, Wolfgang W; Wolters, Volkmar; Wurst, Susanne; Zaitsev, Andrey S; Smith, Henrik G

2017-05-01

Along with the global decline of species richness goes a loss of ecological traits. Associated biotic homogenization of animal communities and narrowing of trait diversity threaten ecosystem functioning and human well-being. High management intensity is regarded as an important ecological filter, eliminating species that lack suitable adaptations. Below-ground arthropods are assumed to be less sensitive to such effects than above-ground arthropods. Here, we compared the impact of management intensity between (grassland vs. forest) and within land-use types (local management intensity) on the trait diversity and composition in below- and above-ground arthropod communities. We used data on 722 arthropod species living above-ground (Auchenorrhyncha and Heteroptera), primarily in soil (Chilopoda and Oribatida) or at the interface (Araneae and Carabidae). Our results show that trait diversity of arthropod communities is not primarily reduced by intense local land use, but is rather affected by differences between land-use types. Communities of Auchenorrhyncha and Chilopoda had significantly lower trait diversity in grassland habitats as compared to forests. Carabidae showed the opposite pattern with higher trait diversity in grasslands. Grasslands had a lower proportion of large Auchenorrhyncha and Carabidae individuals, whereas Chilopoda and Heteroptera individuals were larger in grasslands. Body size decreased with land-use intensity across taxa, but only in grasslands. The proportion of individuals with low mobility declined with land-use intensity in Araneae and Auchenorrhyncha, but increased in Chilopoda and grassland Heteroptera. The proportion of carnivorous individuals increased with land-use intensity in Heteroptera in forests and in Oribatida and Carabidae in grasslands. Our results suggest that gradients in management intensity across land-use types will not generally reduce trait diversity in multiple taxa, but will exert strong trait filtering within individual taxa. The observed patterns for trait filtering in individual taxa are not related to major classifications into above- and below-ground species. Instead, ecologically different taxa resembled each other in their trait diversity and compositional responses to land-use differences. These previously undescribed patterns offer an opportunity to develop management strategies for the conservation of trait diversity across taxonomic groups in permanent grassland and forest habitats. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Environmental Impact of Controlled-Source Explosions in Ethiopia (Project EAGLE): Surface Shaking, Ground Velocities, and Effects on Buildings

NASA Astrophysics Data System (ADS)

Les, A.; Klemperer, S. L.; Keranen, K.; Khan, A.; Maguire, P.

2003-12-01

In January 2003, as part of the Ethiopia-Afar Geoscientific Lithospheric Experiment (EAGLE) we conducted a refraction and wide-angle reflection survey of the Main Ethiopian Rift. 757 RefTek "Texan" seismographs with vertical geophones were deployed in 400 km-long axial and cross-rift lines, with another 231 in a central 3D array 100 km in diameter. An 80-instrument passive array of intermediate and broadband sensors was active during our experiment. We recorded 19 borehole shots loaded in nominal 50-meter boreholes, 2 quarry shots, and 2 lake shots. The shots ranged in size from 50-5750 kg, with the most common shot size being 1 tonne. Prior to loading each shot-hole, we measured distances between shots and the nearest structure, typically un-reinforced mud-and-wood houses, occasionally concrete irrigation ditches and aqueducts. We then used semi-empirical formulae derived by Oriard (Hendron and Oriard, 1972) to calculate expected maximum and minimum bounds on ground velocity at these structures, and selected an appropriate shot size to keep the predicted velocity below the "threshold for cosmetic damage", or 2 inches per second, at the most vulnerable structure. The Oriard formulae are derived from measurements associated with blasting for mining and civil engineering purposes and may not accurately predict the ground velocity from the source depths and explosive type used in the EAGLE and other controlled-source experiments. A detailed, trace-by-trace analysis of maximum ground velocities at our closest seismographs can provide data that will be useful in planning future large-scale seismic experiments. Preliminary results from traces within 20 km of our borehole shots suggest that maximum recorded ground velocities were within or below the maximum-minimum range predicted by Oriard, and hence that larger shot sizes could have been used with acceptable risks. A lake shot fired at the optimum depth (84 m for a 1 tonne shot) produced ground velocities that exceeded the predicted maximum at a few recodrers. However, optimum-depth shots are typically a significant distance offshore (c. 2.3 km for our shot) because of the required depth, so are unlikely to present a hazard to onshore structures. A lake shot fired in a shallower lake at half the optimum depth did not produce ground-velocities that exceed the Oriard maximum. Although we fired shots within 100 m of an unreinforced concrete aqueduct, and within 200 m of poorly engineered native buildings in poor structural condition, no damage was recorded. Our "Texan" seismometers recorded only vertical component velocity, using 4.5 Hz geophones. After removal of the geophone response the peak vertical velocity is typically measured at about 3 Hz and occurs shortly after the first arrival, presumably due to surface waves (ground roll). We are currently extending our analysis to include data from broadband, three-component recorders.

Use of high-resolution ground-penetrating radar in kimberlite delineation

USGS Publications Warehouse

Kruger, J.M.; Martinez, A.; Berendsen, P.

1997-01-01

High-resolution ground-penetrating radar (GPR) was used to image the near-surface extent of two exposed Late Cretaceous kimberlites intruded into lower Permian limestone and dolomite host rocks in northeast Kansas. Six parallel GPR profiles identify the margin of the Randolph 1 kimberlite by the up-bending and termination of limestone reflectors. Five radially-intersecting GPR profiles identify the elliptical margin of the Randolph 2 kimberlite by the termination of dolomite reflectors near or below the kimberlite's mushroom-shaped cap. These results suggest GPR may augment magnetic methods for the delineation of kimberlites or other forceful intrusions in a layered host rock where thick, conductive soil or shale is not present at the surface.

Dry matter and energy partitioning in plants under climatic stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolhar-Nordenkampf, H.R.; Postl, W.F.; Meister, M.H.

1996-12-31

During ontogenesis plants distribute assimilates quite differently among their organs depending on the environmental conditions. In case of high sink capacity energetically cheap storing compounds such as carbohydrates and/or organic acids are formed, whereas during periods with low demand proteins and lipids may be accumulated. Besides ontogenesis, drought and increased CO{sub 2} are able to modify sink capacity and by this transients in the partitioning pattern of carbon are induced. Plants, well adapted to several dry seasons during the year are able to allocate carbon predominantly to below ground organs. During this period many leaves become senescent. In any casemore » stems and remaining green leaves will loose dry matter and energy. With 80% of plants under investigation CO{sub 2} enrichment was shown to induce an enforced allocation of carbon to below ground organs. Roots and Rhizomes, beets and tubers act as a sink for the additionally fixed carbon. It was demonstrated that sink capacity is controlling photosynthetic activity. With respect to agricultural production, to ecosystems and to single plants, climatic change will modify productivity and plants distribution pattern as a consequence of quite different metabolic changes. These responses are depending on the effect of natural and anthropogenic stress factors on the use of enhanced CO{sub 2} and on the allocation of additionally formed assimilates.« less

Simulation of effects of ground-water development on water-levels in glacial-drift aquifers in the Brooten-Belgrade area, west-central Minnesota

USGS Publications Warehouse

Delin, G.N.

1991-01-01

The model was used to simulate the steady-state effects of below-normal precipitation (drought) and hypothetical increases in ground-water development. Model results indicate that reduced recharge and increased pumping during a hypothetical 3-year extended drought would lower regional water levels from 2 to 5 feet in each aquifer and as much as 20 feet in the lowermost aquifer zone; ground-water discharge to the East Branch Chippewa and North Fork Crow Rivers would be reduced by 38 percent. The addition of 10 to 20 hypothetical wells in confined aquifers, pumping 123 to 246 million gallons per year, would result in regional water-level declines of 0.1 to 0.5 feet. Simulated water-level declines in wells completed in the lower part of the system would be as much as 5.0 feet as a result of pumping 246 million gallons per year from 20 hypothetical wells. Water-level declines in overlying and underlying aquifers would range from 0.4 to 2.8 feet. Ground-water discharge to the East Branch Chippewa and North Fork Crow Rivers would be unaffected by the pumpage.

Mapping Above- and Below-Ground Carbon Pools in Boreal Forests: The Case for Airborne Lidar

PubMed Central

Kristensen, Terje; Næsset, Erik; Ohlson, Mikael; Bolstad, Paul V.; Kolka, Randall

2015-01-01

A large and growing body of evidence has demonstrated that airborne scanning light detection and ranging (lidar) systems can be an effective tool in measuring and monitoring above-ground forest tree biomass. However, the potential of lidar as an all-round tool for assisting in assessment of carbon (C) stocks in soil and non-tree vegetation components of the forest ecosystem has been given much less attention. Here we combine the use airborne small footprint scanning lidar with fine-scale spatial C data relating to vegetation and the soil surface to describe and contrast the size and spatial distribution of C pools within and among multilayered Norway spruce (Picea abies) stands. Predictor variables from lidar derived metrics delivered precise models of above- and below-ground tree C, which comprised the largest C pool in our study stands. We also found evidence that lidar canopy data correlated well with the variation in field layer C stock, consisting mainly of ericaceous dwarf shrubs and herbaceous plants. However, lidar metrics derived directly from understory echoes did not yield significant models. Furthermore, our results indicate that the variation in both the mosses and soil organic layer C stock plots appears less influenced by differences in stand structure properties than topographical gradients. By using topographical models from lidar ground returns we were able to establish a strong correlation between lidar data and the organic layer C stock at a stand level. Increasing the topographical resolution from plot averages (~2000 m2) towards individual grid cells (1 m2) did not yield consistent models. Our study demonstrates a connection between the size and distribution of different forest C pools and models derived from airborne lidar data, providing a foundation for future research concerning the use of lidar for assessing and monitoring boreal forest C. PMID:26426532

Mapping Above- and Below-Ground Carbon Pools in Boreal Forests: The Case for Airborne Lidar.

PubMed

Kristensen, Terje; Næsset, Erik; Ohlson, Mikael; Bolstad, Paul V; Kolka, Randall

2015-01-01

A large and growing body of evidence has demonstrated that airborne scanning light detection and ranging (lidar) systems can be an effective tool in measuring and monitoring above-ground forest tree biomass. However, the potential of lidar as an all-round tool for assisting in assessment of carbon (C) stocks in soil and non-tree vegetation components of the forest ecosystem has been given much less attention. Here we combine the use airborne small footprint scanning lidar with fine-scale spatial C data relating to vegetation and the soil surface to describe and contrast the size and spatial distribution of C pools within and among multilayered Norway spruce (Picea abies) stands. Predictor variables from lidar derived metrics delivered precise models of above- and below-ground tree C, which comprised the largest C pool in our study stands. We also found evidence that lidar canopy data correlated well with the variation in field layer C stock, consisting mainly of ericaceous dwarf shrubs and herbaceous plants. However, lidar metrics derived directly from understory echoes did not yield significant models. Furthermore, our results indicate that the variation in both the mosses and soil organic layer C stock plots appears less influenced by differences in stand structure properties than topographical gradients. By using topographical models from lidar ground returns we were able to establish a strong correlation between lidar data and the organic layer C stock at a stand level. Increasing the topographical resolution from plot averages (~2000 m2) towards individual grid cells (1 m2) did not yield consistent models. Our study demonstrates a connection between the size and distribution of different forest C pools and models derived from airborne lidar data, providing a foundation for future research concerning the use of lidar for assessing and monitoring boreal forest C.

Comprehension of Students with or without Learning Disabilities: Identification of Narrative Themes and Idiosyncratic Text Representations.

ERIC Educational Resources Information Center

Williams, Joanna P.

1993-01-01

Ten learning-disabled adolescents (LDs) performed a reading comprehension task below the level of same-age nondisabled students (NLDs) but at the same level as younger NLDs (YNDs). On a measure of incipient awareness of theme, LDs scored below YNDs. Why LDs have difficulty getting the point is discussed. (SLD)

Orthogonal stimulus-response compatibility effects emerge even when the stimulus position is task irrelevant.

PubMed

Nishimura, Akio; Yokosawa, Kazuhiko

2006-06-01

The above-right/below-left mapping advantage with vertical stimuli and horizontal responses is known as the orthogonal stimulus-response compatibility (SRC) effect. We investigated whether the orthogonal SRC effect emerges with irrelevant stimulus dimensions. In Experiment 1, participants responded with a right or left key press to the colour of the stimulus presented above or below the fixation. We observed an above-right/below-left advantage (orthogonal Simon effect). In Experiment 2, we manipulated the polarity in the response dimension by varying the horizontal location of the response set. The orthogonal Simon effect decreased and even reversed as the left response code became more positive. This result provides evidence for the automatic activation of the positive and negative response codes by the corresponding positive and negative stimulus codes. These findings extended the orthogonal SRC effect based on coding asymmetry to an irrelevant stimulus dimension.

Insulating and metallic spin glass in K xFe 2-δ-yNi ySe 2 (0.06 ≤ y ≤ 1.44 ) single crystals

DOE PAGES

Ryu, Hyejin; Abeykoon, Milinda; Wang, Kefeng; ...

2015-05-04

We report electron doping effects by Ni in K xFe 2-δ-yNi ySe₂ (0.06 ≤ y ≤ 1.44) single crystal alloys. A rich ground state phase diagram is observed. Thus, a small amount of Ni (~ 4%) suppressed superconductivity below 1.8 K, inducing insulating spin glass magnetic ground state for higher Ni content. With further Ni substitution, metallic resistivity is restored. For high Ni concentration in the lattice the unit cell symmetry is high symmetry I4/ mmm with no phase separation whereas both I4/ m + I4/ mmm space groups were detected in the phase separated crystals when concentration of Nimore » < Fe. The absence of superconductivity coincides with the absence of crystalline Fe vacancy order.« less

Proper Employment of Special Operations Forces: Geographic Combatant Command Planner Considerations for Special Operations Forces Employment

DTIC Science & Technology

2010-04-01

October 2008, in Figure 2-1 below. TACON Best Practices 1) For the respective commanders to jointly determine the required tasks and organize the... organization . 2) Provide the gaining commander of the TACON force the requisite expertise to effectively plan and exercise TACON of the force. We sometimes...the TACON of SOF is given to an organization other than the parent organization . As changes occur, a plan may change requiring a shift in end state

Benzene Exposures and Risk Potential for Vehicle Mechanics from Gasoline and Petroleum-Derived Products.

PubMed

Williams, Pamela R D; Mani, Ashutosh

2015-01-01

Benzene exposures among vehicle mechanics in the United States and abroad were characterized using available data from published and unpublished studies. In the United States, the time-weighted-average (TWA) airborne concentration of benzene for vehicle mechanics averaged 0.01-0.05 ppm since at least the late 1970s, with maximal TWA concentrations ranging from 0.03 to 0.38 ppm. Benzene exposures were notably lower in the summer than winter and in the Southwest compared to other geographic regions, but significantly higher during known gasoline-related tasks such as draining a gas tank or changing a fuel pump or fuel filter. Measured airborne concentrations of benzene were also generally greater for vehicle mechanics in other countries, likely due to the higher benzene content of gasoline and other factors. Short-term airborne concentrations of benzene frequently exceeded 1 ppm during gasoline-related tasks, but remained below 0.2 ppm for tasks involving other petroleum-derived products such as carburetor and brake cleaner or parts washer solvent. Application of a two-zone mathematical model using reasonable input values from the literature yielded predicted task-based benzene concentrations during gasoline and aerosol spray cleaner scenarios similar to those measured for vehicle mechanics during these types of tasks. When evaluated using appropriate biomarkers, dermal exposures were found to contribute little to total benzene exposures for this occupational group. Available data suggest that vehicle mechanics have not experienced significant exposures to benzene in the workplace, except perhaps during short-duration gasoline-related tasks, and full-shift benzene exposures have remained well below current and contemporaneous occupational exposure limits. These findings are consistent with epidemiology studies of vehicle mechanics, which have not demonstrated an increased risk of benzene-induced health effects in this cohort of workers. Data and information presented here may be used to assess past, current, or future exposures and risks to benzene for vehicle mechanics who may be exposed to gasoline or other petroleum-derived products.

A study of electron density profiles in relation to ionization sources and ground-based radio wave absorption measurements, part 2

NASA Technical Reports Server (NTRS)

Gnanalingam, S.; Kane, J. A.

1975-01-01

The D-region ion production functions are used to calculate the relationship between radio wave absorption and the flux level of X-rays in the 1-8A wavelength band. In order to bring this calculation into agreement with the empirically established relationship, it was found necessary to reduce by, a factor of about 5, the Meira nitric oxide densities below 90 km.

Rhythm production at school entry as a predictor of poor reading and spelling at the end of first grade.

PubMed

Lundetræ, Kjersti; Thomson, Jenny M

2018-01-01

Rhythm plays an organisational role in the prosody and phonology of language, and children with literacy difficulties have been found to demonstrate poor rhythmic perception. This study explored whether students' performance on a simple rhythm task at school entry could serve as a predictor of whether they would face difficulties in word reading and spelling at the end of grade 1. The participants were 479 Norwegian 6-year-old first graders randomized as controls in the longitudinal RCT on track (n = 1171). Rhythmic timing and pre-reading skills were tested individually at school entry on a digital tablet. On the rhythm task, the students were told to tap a drum appearing on the screen to two different rhythms (2 Hz paced and 1.5 Hz paced). Children's responses were recorded as they tapped on the screen with their index finger. Significant group differences were found in rhythm tapping ability measured at school entry, when groups were defined upon whether children went on to score above or below the 20th percentile reading and spelling thresholds in national assessment tests at the end of grade one. Inclusion of the school-entry rhythmic tapping measure into a model of classification accuracy for above or below threshold reading and spelling improved accuracy of classification by 6.2 and 9.2% respectively.

ESI-FTICR-MS Molecular Characterization of DOM Degradation under Warming in Tundra Soils from Barrow, Alaska

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hongmei Chen; Ziming Yang; Rosalie Chu

This dataset provides the results of warming incubation of Arctic soils from trough areas of a high-center polygon at the Barrow Environmental Observatory (BEO) in northern Alaska, United States. The organic-rich soil (8-20 cm below ground surface) and the mineral-rich soil (22-45 cm below surface) were separated, and the thawed and homogenized subsamples from each soil were incubated at -2 degrees C or 8 degrees C for 122 days under anoxic conditions (headspace filled with N2). The extracted DOM from soil samples were analyzed by Fourier transform ion cyclotron resonance mass spectrometry coupled with electrospray ionization (ESI-FTICR-MS). Reported analytes includemore » soil water content, dissolved organic carbon, total organic carbon, MS peaks' m/z and intensities, and elemental composition of identified molecular formulas.« less

The effects of experimental pain and induced optimism on working memory task performance.

PubMed

Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

2016-07-01

Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found that optimism protected against this pain-induced performance deterioration. Experimentally induced pain impairs concurrent but not subsequent working memory task performance. Manipulated optimism did not counteract pain-induced deterioration of 2-back performance. It is important to explore factors that may diminish the negative impact of pain on the ability to function in daily life, as pain itself often cannot be remediated. We are planning to conduct future studies that should shed further light on the conditions, contexts and executive operations for which optimism can act as a protective factor. Copyright © 2016 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Respirable Crystalline Silica Exposures During Asphalt Pavement Milling at Eleven Highway Construction Sites

PubMed Central

Hammond, Duane R.; Shulman, Stanley A.; Echt, Alan S.

2016-01-01

Asphalt pavement milling machines use a rotating cutter drum to remove the deteriorated road surface for recycling. The removal of the road surface has the potential to release respirable crystalline silica, to which workers can be exposed. This paper describes an evaluation of respirable crystalline silica exposures to the operator and ground worker from two different half-lane and larger asphalt pavement milling machines that had ventilation dust controls and water-sprays designed and installed by the manufacturers. Manufacturer A completed milling for eleven days at four highway construction sites in Wisconsin, while Manufacturer B completed milling for ten days at seven highway construction sites in Indiana. To evaluate the dust controls, full-shift personal breathing zone air samples were collected from an operator and ground worker during the course of normal employee work activities of asphalt pavement milling at eleven different sites. Forty-two personal breathing zone air samples were collected over 21 days (sampling on an operator and ground worker each day). All samples were below 50 µg/m3 for respirable crystalline silica, the National Institute for Occupational Safety and Health recommended exposure limit. The geometric mean personal breathing zone air sample was 6.2 µg/m3 for the operator and 6.1 µg/m3 for the ground worker for the Manufacturer A milling machine. The geometric mean personal breathing zone air sample was 4.2 µg/m3 for the operator and 9.0 µg/m3 for the ground worker for the Manufacturer B milling machine. In addition, upper 95% confidence limits for the mean exposure for each occupation were well below 50 µg/m3 for both studies. The silica content in the bulk asphalt material being milled ranged from 7% to 23% silica for roads milled by Manufacturer A and from 5% to 12% silica for roads milled by Manufacturer B. The results indicate that engineering controls consisting of ventilation controls in combination with water-sprays are capable of controlling occupational exposures to respirable crystalline silica generated by asphalt pavement milling machines on highway construction sites. PMID:26913983

Respirable crystalline silica exposures during asphalt pavement milling at eleven highway construction sites.

PubMed

Hammond, Duane R; Shulman, Stanley A; Echt, Alan S

2016-07-01

Asphalt pavement milling machines use a rotating cutter drum to remove the deteriorated road surface for recycling. The removal of the road surface has the potential to release respirable crystalline silica, to which workers can be exposed. This article describes an evaluation of respirable crystalline silica exposures to the operator and ground worker from two different half-lane and larger asphalt pavement milling machines that had ventilation dust controls and water-sprays designed and installed by the manufacturers. Manufacturer A completed milling for 11 days at 4 highway construction sites in Wisconsin, and Manufacturer B completed milling for 10 days at 7 highway construction sites in Indiana. To evaluate the dust controls, full-shift personal breathing zone air samples were collected from an operator and ground worker during the course of normal employee work activities of asphalt pavement milling at 11 different sites. Forty-two personal breathing zone air samples were collected over 21 days (sampling on an operator and ground worker each day). All samples were below 50 µg/m(3) for respirable crystalline silica, the National Institute for Occupational Safety and Health recommended exposure limit. The geometric mean personal breathing zone air sample was 6.2 µg/m(3) for the operator and 6.1 µg/m(3) for the ground worker for the Manufacturer A milling machine. The geometric mean personal breathing zone air sample was 4.2 µg/m(3) for the operator and 9.0 µg/m(3) for the ground worker for the Manufacturer B milling machine. In addition, upper 95% confidence limits for the mean exposure for each occupation were well below 50 µg/m(3) for both studies. The silica content in the bulk asphalt material being milled ranged from 7-23% silica for roads milled by Manufacturer A and from 5-12% silica for roads milled by Manufacturer B. The results indicate that engineering controls consisting of ventilation controls in combination with water-sprays are capable of controlling occupational exposures to respirable crystalline silica generated by asphalt pavement milling machines on highway construction sites.

Riparian soil seed banks and the potential for passive restoration of giant reed infested areas in Webb County, Texas

USDA-ARS?s Scientific Manuscript database

Habitat restoration projects can use seed bank information as early warning systems of patterns or degrees of habitat degradation; as changes in above ground vegetation directly impact below ground seed distribution. In multiple strategy restoration efforts, seed bank quality can be used as a decidi...

Research in seismology and earthquake engineering in Venezuela

USGS Publications Warehouse

Urbina, L.; Grases, J.

1983-01-01

After the July 29, 1967, damaging earthquake (with a moderate magnitude of 6.3) caused widespread damage to the northern coastal area of Venezuela and to the Caracas Valley, the Venezuelan Government decided to establish a Presidential Earthquake Commission. This commission undertook the task of coordinating the efforts to study the after-effects of the earthquake. The July 1967 earthquake claimed numerous lives and caused extensive damage to the capital of Venezuela. In 1968, the U.S Geological Survey conducted a seismological field study in the northern coastal area and in the Caracas Valley of Venezuela. the objective was to study the area that sustained severe, moderate, and no damage to structures. A reported entitled Ground Amplification Studies in Earthquake Damage Areas: The Caracas Earthquake of 1967 documented, for the first time, short-period seismic wave ground-motion amplifications in the Caracas Valley. Figure 1 shows the area of severe damage in the Los Palos Grantes suburb and the correlation with depth of alluvium and the arabic numbers denote the ground amplification factor at each site in the area. the Venezuelan Government initiated many programs to study in detail the damage sustained and to investigate the ongoing construction practices. These actions motivated professionals in the academic, private, and Government sectors to develops further capabilities and self-sufficiency in the fields of engineering and seismology. Allocation of funds was made to assist in training professionals and technicians and in developing new seismological stations and new programs at the national level in earthquake engineering and seismology. A brief description of the ongoing programs in Venezuela is listed below. these programs are being performed by FUNVISIS and by other national organizations listed at the end of this article.   

CFD predictions of near-field pressure signatures of a low-boom aircraft

NASA Technical Reports Server (NTRS)

Fouladi, Kamran; Baize, Daniel G.

1992-01-01

A three dimensional Euler marching code has been utilized to predict near-field pressure signatures of an aircraft with low boom characteristics. Computations were extended to approximately six body lengths aft of the aircraft in order to obtain pressure data at three body lengths below the aircraft for a cruise Mach number of 1.6. The near-field pressure data were extrapolated to the ground using a Whitham based method. The distance below the aircraft where the pressure data are attained is defined in this paper as the 'separation distance.' The influences of separation distances and the still highly three-dimensional flow field on the predicted ground pressure signatures and boom loudness are presented in this paper.

Bilateral neuromuscular and force differences during a plyometric task.

PubMed

Ball, Nick B; Scurr, Joanna C

2009-08-01

The purpose of this article is to compare the bilateral neuromuscular and force contribution during a plyometric bounce drop jump task and to assess the affects of nonsimultaneous foot placement. Sixteen male participants performed bounce drop jumps from a height of 0.4 m. Mean peak electromyography activity of the soleus, medial, and lateral gastrocnemius of both legs was recorded from each phase of the drop jump and normalized to a reference dynamic muscle action. Resultant ground reaction force, ground contact time, and duration of the drop jumps were recorded from each leg. Multivariate analysis of variance was used to compare bilateral electromyographic activity, resultant peak ground reaction force, and contact duration. Pearson's correlations (r) ascertained relationships between normalized electromyographic activity and contact time. Significant differences were shown between left and right triceps surae normalized electromyography during precontact and contact40ms (p < 0.01). No significant differences were present in the contactpost40ms phase (p > 0.01). Significant differences were found between normalized soleus electromyography and both gastrocnemii for both legs during precontact (p < 0.01). No significant differences were found for within-leg normalized electromyography for the contact40ms phases and contactpost40ms phase (p > 0.01). Weak relationships were found between normalized electromyographic activity and nonsimultaneous foot contact (r < 0.2). This study showed differences between left and right triceps surae in neuromuscular strategies engaged in the early stages of a drop jump task. Differences in contact time initiation were present; however, they are not significant enough to cause neuromuscular differences in the plantar flexor muscles.

Evaluating office lighting environments: Second-level analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, B.L.; Fisher, W.S.; Gillette, G.L.

1989-04-01

Data from a post-occupancy evaluation (POE) of 912 work stations with lighting power density (LPD), photometric, and occupant-response measures were examined in a detailed, second-level analysis. Seven types of lighting systems were identified with different combinations of direct and indirect ambient lighting, and task lighting and daylight. The mean illuminances at the primary task location were within the IES target values for office task with a range of mean illuminances from 32 to 75 fc, depending on the lighting system. The median LPD was about 2.36 watts/sq ft, with about one-third the work stations having LPD's at or below 2.0more » watts/sq ft. Although a majority of the occupants (69%) were satisfied about their lighting, the highest percentage of those expressing dissatisfaction (37%) with lighting had an indirect fluorescent furniture-mounted (IFFM) system. The negative reaction of so many people to the IFFM system suggests that the combination of task lighting with an indirect ambient system had an important influence on lighting satisfaction, even though task illuminances tended to be higher with the IFFM system. Concepts of lighting quality, visual health, and control were explored, as well as average luminance to explain the negative reactions to the combination of indirect lighting with furniture-mounted lighting.« less

Effects of Grazing on Above- vs. Below-Ground Biomass Allocation of Alpine Grasslands on the Northern Tibetan Plateau

PubMed Central

Zeng, Chaoxu; Wu, Jianshuang; Zhang, Xianzhou

2015-01-01

Biomass allocation is an essential concept for understanding above- vs. below-ground functions and for predicting the dynamics of community structure and ecosystem service under ongoing climate change. There is rare available knowledge of grazing effects on biomass allocation in multiple zonal alpine grassland types along climatic gradients across the Northern Tibetan Plateau. We collected the peak above- and below-ground biomass (AGB and BGB) values at 106 pairs of well-matched grazed vs. fenced sites during summers of 2010–2013, of which 33 pairs were subject to meadow, 52 to steppe and 21 to desert-steppe. The aboveground net primary productivity (ANPP) was represented by the peak AGB while the belowground net primary productivity (BNPP) was estimated from ANPP, the ratio of living vs. dead BGB, and the root turnover rate. Two-ways analyses of variance (ANOVA) and paired samples comparisons with t-test were applied to examine the effects of pasture managements (PMS, i.e., grazed vs. fenced) and zonal grassland types on both ANPP and BNPP. Allometric and isometric allocation hypotheses were also tested between logarithmically transformed ANPP and BNPP using standardized major axis (SMA) analyses across grazed, fenced and overall sites. In our study, a high community-dependency was observed to support the allometric biomass allocation hypothesis, in association with decreased ANPP and a decreasing-to-increasing BNPP proportions with increasing aridity across the Northern Tibetan Plateau. Grazing vs. fencing seemed to have a trivial effect on ANPP compared to the overwhelming influence of different zonal grassland types. Vegetation links above- and below-ground ecological functions through integrated meta-population adaptive strategies to the increasing severity of habitat conditions. Therefore, more detailed studies on functional diversity are essentially to achieve conservation and sustainability goals under ongoing climatic warming and intensifying human influences. PMID:26284515

Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill Stanley; Patrick Gonzalez; Sandra Brown

2005-10-01

The Nature Conservancy is participating in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research project is ''Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration''. The objectives of the project are to: (1) improve carbon offset estimates produced in both the planning and implementation phases of projects; (2) build valid and standardized approaches to estimate project carbon benefits at a reasonable cost; and (3) lay the groundwork for implementing cost-effective projects,more » providing new testing ground for biodiversity protection and restoration projects that store additional atmospheric carbon. This Technical Progress Report discusses preliminary results of the six specific tasks that The Nature Conservancy is undertaking to answer research needs while facilitating the development of real projects with measurable greenhouse gas reductions. The research described in this report occurred between April 1st , 2005 and June 30th, 2005. The specific tasks discussed include: Task 1: carbon inventory advancements; Task 2: emerging technologies for remote sensing of terrestrial carbon; Task 3: baseline method development; Task 4: third-party technical advisory panel meetings; Task 5: new project feasibility studies; and Task 6: development of new project software screening tool.« less

Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bill Stanley; Patrick Gonzalez; Sandra Brown

2006-01-01

The Nature Conservancy is participating in a Cooperative Agreement with the Department of Energy (DOE) National Energy Technology Laboratory (NETL) to explore the compatibility of carbon sequestration in terrestrial ecosystems and the conservation of biodiversity. The title of the research project is ''Application and Development of Appropriate Tools and Technologies for Cost-Effective Carbon Sequestration''. The objectives of the project are to: (1) improve carbon offset estimates produced in both the planning and implementation phases of projects; (2) build valid and standardized approaches to estimate project carbon benefits at a reasonable cost; and (3) lay the groundwork for implementing cost-effective projects,more » providing new testing ground for biodiversity protection and restoration projects that store additional atmospheric carbon. This Technical Progress Report discusses preliminary results of the six specific tasks that The Nature Conservancy is undertaking to answer research needs while facilitating the development of real projects with measurable greenhouse gas reductions. The research described in this report occurred between April 1st , 2005 and June 30th, 2005. The specific tasks discussed include: Task 1: carbon inventory advancements; Task 2: emerging technologies for remote sensing of terrestrial carbon; Task 3: baseline method development; Task 4: third-party technical advisory panel meetings; Task 5: new project feasibility studies; and Task 6: development of new project software screening tool.« less

The gene normalization task in BioCreative III

PubMed Central

2011-01-01

Background We report the Gene Normalization (GN) challenge in BioCreative III where participating teams were asked to return a ranked list of identifiers of the genes detected in full-text articles. For training, 32 fully and 500 partially annotated articles were prepared. A total of 507 articles were selected as the test set. Due to the high annotation cost, it was not feasible to obtain gold-standard human annotations for all test articles. Instead, we developed an Expectation Maximization (EM) algorithm approach for choosing a small number of test articles for manual annotation that were most capable of differentiating team performance. Moreover, the same algorithm was subsequently used for inferring ground truth based solely on team submissions. We report team performance on both gold standard and inferred ground truth using a newly proposed metric called Threshold Average Precision (TAP-k). Results We received a total of 37 runs from 14 different teams for the task. When evaluated using the gold-standard annotations of the 50 articles, the highest TAP-k scores were 0.3297 (k=5), 0.3538 (k=10), and 0.3535 (k=20), respectively. Higher TAP-k scores of 0.4916 (k=5, 10, 20) were observed when evaluated using the inferred ground truth over the full test set. When combining team results using machine learning, the best composite system achieved TAP-k scores of 0.3707 (k=5), 0.4311 (k=10), and 0.4477 (k=20) on the gold standard, representing improvements of 12.4%, 21.8%, and 26.6% over the best team results, respectively. Conclusions By using full text and being species non-specific, the GN task in BioCreative III has moved closer to a real literature curation task than similar tasks in the past and presents additional challenges for the text mining community, as revealed in the overall team results. By evaluating teams using the gold standard, we show that the EM algorithm allows team submissions to be differentiated while keeping the manual annotation effort feasible. Using the inferred ground truth we show measures of comparative performance between teams. Finally, by comparing team rankings on gold standard vs. inferred ground truth, we further demonstrate that the inferred ground truth is as effective as the gold standard for detecting good team performance. PMID:22151901

The gene normalization task in BioCreative III.

PubMed

Lu, Zhiyong; Kao, Hung-Yu; Wei, Chih-Hsuan; Huang, Minlie; Liu, Jingchen; Kuo, Cheng-Ju; Hsu, Chun-Nan; Tsai, Richard Tzong-Han; Dai, Hong-Jie; Okazaki, Naoaki; Cho, Han-Cheol; Gerner, Martin; Solt, Illes; Agarwal, Shashank; Liu, Feifan; Vishnyakova, Dina; Ruch, Patrick; Romacker, Martin; Rinaldi, Fabio; Bhattacharya, Sanmitra; Srinivasan, Padmini; Liu, Hongfang; Torii, Manabu; Matos, Sergio; Campos, David; Verspoor, Karin; Livingston, Kevin M; Wilbur, W John

2011-10-03

We report the Gene Normalization (GN) challenge in BioCreative III where participating teams were asked to return a ranked list of identifiers of the genes detected in full-text articles. For training, 32 fully and 500 partially annotated articles were prepared. A total of 507 articles were selected as the test set. Due to the high annotation cost, it was not feasible to obtain gold-standard human annotations for all test articles. Instead, we developed an Expectation Maximization (EM) algorithm approach for choosing a small number of test articles for manual annotation that were most capable of differentiating team performance. Moreover, the same algorithm was subsequently used for inferring ground truth based solely on team submissions. We report team performance on both gold standard and inferred ground truth using a newly proposed metric called Threshold Average Precision (TAP-k). We received a total of 37 runs from 14 different teams for the task. When evaluated using the gold-standard annotations of the 50 articles, the highest TAP-k scores were 0.3297 (k=5), 0.3538 (k=10), and 0.3535 (k=20), respectively. Higher TAP-k scores of 0.4916 (k=5, 10, 20) were observed when evaluated using the inferred ground truth over the full test set. When combining team results using machine learning, the best composite system achieved TAP-k scores of 0.3707 (k=5), 0.4311 (k=10), and 0.4477 (k=20) on the gold standard, representing improvements of 12.4%, 21.8%, and 26.6% over the best team results, respectively. By using full text and being species non-specific, the GN task in BioCreative III has moved closer to a real literature curation task than similar tasks in the past and presents additional challenges for the text mining community, as revealed in the overall team results. By evaluating teams using the gold standard, we show that the EM algorithm allows team submissions to be differentiated while keeping the manual annotation effort feasible. Using the inferred ground truth we show measures of comparative performance between teams. Finally, by comparing team rankings on gold standard vs. inferred ground truth, we further demonstrate that the inferred ground truth is as effective as the gold standard for detecting good team performance.

Water resources of the Red Lake Indian Reservation, northwestern Minnesota

USGS Publications Warehouse

Ruhl, J.F.

1991-01-01

The quality of ground water is suitable for drinking and other household uses, and the quality of the surface water generally meets U.S. Environmental Protection Agency criteria necessary for the maintenance of aquatic life. The major ions in both ground and surface water are calcium, magnesium, and bicarbonate. Lower and Upper Red Lakes are eutrophic to mesotrophic on the basis of their summer Secchi disk-transparency readings, which ranged from 2.6 to 8.2 feet. The concentration of total organic carbon in samples from Lower and Upper Red Lakes and four streams were below or, in the case of one stream, about equal to 30 milligrams per liter, which is indicative of water little affected by human activities. The sample with the highest organic carbon content was collected from a stream that drained peatlands, which were probably sources of organic matter in the runoff. The concentration of nitrite plus nitrate in samples collected from Lower and Upper Red Lakes in late summer was below 0.01 milligrams per liter, which is characteristic of water uncontaminated by animal wastes. Total phosphorus in these samples ranged from 0.01 to 0.02 milligrams per liter. Most of this phosphorus was in the particulate organic fraction because of the abundance of phytoplankton.

Helical order and multiferroicity in the S =1/2 quasi-kagome system KCu3As2O7(OD)3

NASA Astrophysics Data System (ADS)

Nilsen, G. J.; Okamoto, Y.; Ishikawa, H.; Simonet, V.; Colin, C. V.; Cano, A.; Chapon, L. C.; Hansen, T.; Mutka, H.; Hiroi, Z.

2014-04-01

Several Cu2+ hydroxide minerals have been recently identified as candidate realizations of the S=1/2 kagome Heisenberg model. In this context, we have studied the distorted system KCu3As2O7(OD)3 using neutron scattering and bulk measurements. Although the distortion favors magnetic order over a spin liquid ground state, refinement of the magnetic diffraction pattern below TN1=7.05(5) K yields a complex helical structure with k =(0.77,0,0.11). This structure, as well as the spin excitation spectrum, are well described by a classical Heisenberg model with ferromagnetic nearest neighbor couplings. Multiferroicity is observed below TN1, with an unusual crossover between improper and pseudoproper behavior occurring at TN2=5.5 K. The polarization at T =2 K is P =1.5μCm-2. The properties of KCu3As2O7(OD)3 highlight the variety of physics which arise from the interplay of spin and orbital degrees of freedom in Cu2+ kagome systems.

Age-related differences in postural adjustments in connection with different tasks involving weight transfer while standing.

PubMed

Jonsson, Erika; Henriksson, Marketta; Hirschfeld, Helga

2007-10-01

Weight transfer designed to change the area of the supportive base during the performance of three different motor tasks (one-leg stance, tandem stance and gait initiation) was examined both in healthy, physically active elderly people and younger adults. The former two tasks are balance tests used clinically. Our hypothesis was that the elderly subjects would demonstrate age-related changes in their postural adjustments that could be detected by analysis of the ground reaction forces. While 24 healthy elderly adults (65-77 years of age) and 26 younger adults (24-40 years of age) performed these three tasks, the ground reaction forces were recorded from two force plates. Prior to the onset of all three tasks, the elderly placed significantly more weight on the leg that was to provide support (the stance leg), than did the younger individuals. The analyses revealed two distinct phases of weight transfer, i.e., an initial thrust and a subsequent unloading phase. The elderly individuals exhibited a significantly longer unloading phase, as well as a higher frequency of peaks of vertical and lateral forces during this phase. Moreover, the maximal force rate during this phase was achieved at an earlier time point by the elderly. However, both groups generated forces of similar magnitudes and force rates. In conclusion, our findings indicate the presence of age-related differences in the temporal phasing of the ground reaction forces in all three of these tasks involving weight transfer, whereas the magnitude and rates of change of these forces are independent of age.

ForestCrowns: a software tool for analyzing ground-based digital photographs of forest canopies

Treesearch

Matthew F. Winn; Sang-Mook Lee; Phillip A. Araman

2013-01-01

Canopy coverage is a key variable used to characterize forest structure. In addition, the light transmitted through the canopy is an important ecological indicator of plant and animal habitat and understory climate conditions. A common ground-based method used to document canopy coverage is to take digital photographs from below the canopy. To assist with analyzing...