WorldWideScience

Sample records for winter field experiment

  1. Study on the weediness of winter wheat in a long-term fertilization field experiment.

    Science.gov (United States)

    Lehoczky, E; Kismányoky, A; Kismányoky, T

    2006-01-01

    The study was carried out in Keszthely, in the long-term fertilization field experiment in April of 2005. In the experiment we had opportunity to compare the weediness in NPK and NPK + FYM* treatments, and we could study the effect of increasing N dosis on the weeds and winter wheat. The weed survey was made on the 20th of April at the end of tillering. For the weed survey used the Balázs-Ujvárosi method. After that we collected all the weeds from the plots per 1 m2. We counted, measured the fresh and dry matter weight of aerial parts. Winter wheat sampels were taken also from all plots (1 running meter per plot). In the experiment 10 weed species were found, 9 annual: Ambrosia artemisiifolia, Consolida regalis, Galium aparine, Lamiunt amplexicaule, Matricaria inodora, Papaver rhoeas, Stellaria media, Veronica hederifolia, Veronica triphyllos, and 1 perennial: Cirsium arvense. Veronica hederifolia was the dominant species in both fertilized plots, Stellaria media has the second highest weed coverage. The manuring treatments, and the N-dosis has important and significantly effect to the weedeness and the biomass production of winter wheat. On the control plots was the relation of biomass weight of weeds the highest. This relation reduced to the effect of N treatments, wich had an favorable effect on the winter wheat.

  2. Field Evaluation of Highly Insulating Windows in the Lab Homes: Winter Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Graham B.; Widder, Sarah H.; Bauman, Nathan N.

    2012-06-01

    This field evaluation of highly insulating windows was undertaken in a matched pair of 'Lab Homes' located on the Pacific Northwest National Laboratory (PNNL) campus during the 2012 winter heating season. Improving the insulation and solar heat gain characteristics of a home's windows has the potential to significantly improve the home's building envelope and overall thermal performance by reducing heat loss (in the winter), and cooling loss and solar heat gain (in the summer) through the windows. A high quality installation and/or window retrofit will also minimize or reduce air leakage through the window cavity and thus also contribute to reduced heat loss in the winter and cooling loss in the summer. These improvements all contribute to decreasing overall annual home energy use. Occupant comfort (non-quantifiable) can also be increased by minimizing or eliminating the cold 'draft' (temperature) many residents experience at or near window surfaces that are at a noticeably lower temperature than the room air temperature. Lastly, although not measured in this experiment, highly insulating windows (triple-pane in this experiment) also have the potential to significantly reduce the noise transmittance through windows compared to standard double-pane windows. The metered data taken in the Lab Homes and data analysis presented here represent 70 days of data taken during the 2012 heating season. As such, the savings from highly insulating windows in the experimental home (Lab Home B) compared to the standard double-pane clear glass windows in the baseline home (Lab Home A) are only a portion of the energy savings expected from a year-long experiment that would include a cooling season. The cooling season experiment will take place in the homes in the summer of 2012, and results of that experiment will be reported in a subsequent report available to all stakeholders.

  3. The History of Winter: A Professional Development "Teacher as Scientist" Experiential Learning Field Experience.

    Science.gov (United States)

    Gabrys, R. E.

    2007-12-01

    Each year since 2000, the NASA Goddard History of Winter (HOW) program has allowed teachers to develop an understanding of the consequences of one segment of the orbit of the tilted Earth in its path around the sun. Scientists from NASA, CRREL, and Michigan Tech, supported by the Whiteface Observatory, and the science program at Northwood School in Lake Placid, New York, use the weather and the stratigraphy in the ice and snow, consequences of the weather changes, as "teachers" in a team study of the winter record. Snow in the air and on the ground, ice, its crystal structure and axial orientation, and the ecosystem consequences of snow and ice constitute the weeklong content package. Teacher Professional Development Standards A, B, C, and D were the guiding principles in developing HOW with a content structure formulated as protocols to serve as inserts into lesson plans and inquiry guides. The concept of HOW within NASA is to provide understanding of the WHY? and WHAT? of satellite remote sensing. The content is appropriate ground validation in that techniques presented in protocols are identical to those used by professionals who study snow pits, evaluate features in snow metamorphism, and study thin sections of ice cores drilled in ice caps and glaciers. The HOW Teacher as scientist (TAS) model is a flexible model. HOW enables teachers who are required to use inquiry-based facilitation in the classroom to experience inquiry themselves. Teachers with little science content background as well as those with Science degrees have participated in HOW working alongside of the science team. Accommodations are made through differentiation of instruction so that each group leaves with a mastery of the content that is appropriate for the transition to presentation in the classroom. Each year builds on the previous year ensuring a time series record of the history of winter-by itself a learning experience. An offshoot of the NASA Goddard Center History of Winter (HOW

  4. Winter/Summer Monsoon Experiment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Winter/Summer Monsoon Experiment (MONEX) was conducted during the First Global GARP (Global Atmospheric Research Program) Experiment (FGGE). An international...

  5. Geomagnetic Field Variation during Winter Storm at Localized ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... 67.52° N; 23.38° E. We have studied all the geomagnetic storms that occurred during winter season of the year 2004–2005. We observed that at Southern Hemisphere the variation is large as compared to the Northern Hemisphere. Geomagnetic field components vary when the interplanetary magnetic field ...

  6. Seed deterioration in flooded agricultural fields during winter

    Science.gov (United States)

    Nelms, C.O.; Twedt, D.J.

    1996-01-01

    We determined rate of seed deterioration for 3 crops (corn, rice, and soybean) and 8 weeds commonly found in agricultural fields and moist-soil management units in the Mississippi Alluvial Valley (MAV). The weeds were broadleaf signalgrass (Brachiaria platyphylla), junglerice barnyardgrass (Echinochloa colonum), morningglory (Ipomoea sp.), panic grass (Panicum sp.), bull paspalum (Paspalum boscianum), red rice (Oryza sativa), hemp sesbania (Sesbania exaltata), and bristlegrass (Setaria sp.). Weed seeds, except morningglory, deteriorated slower than corn and soybean, whereas rice decomposed slower than all weed seeds except red rice and bull paspalum. For land managers desiring to provide plant food for wintering waterfowl, rice is clearly the most persistent small grain crop in the MAV. Persistence of weed seeds under flooded conditions throughout winter makes them a cost-effective alternative to traditional crops on land managed for waterfowl.

  7. Cosmic Magnetic Fields : XXV Canary Islands Winter School of Astrophysics

    CERN Document Server

    Martinez Gonzalez, Maria Jesus

    2018-01-01

    Magnetic fields pervade the universe and play an important role in many astrophysical processes. However, they require specialised observational tools, and are challenging to model and understand. This volume provides a unified view of magnetic fields across astrophysical and cosmological contexts, drawing together disparate topics that are rarely covered together. Written by the lecturers of the XXV Canary Islands Winter School, it offers a self-contained introduction to cosmic magnetic fields on a range of scales. The connections between the behaviours of magnetic fields in these varying contexts are particularly emphasised, from the relatively small and close ranges of the Sun, planets and stars, to galaxies and clusters of galaxies, as well as on cosmological scales. Aimed at young researchers and graduate students, this up-to-date review uniquely brings together a subject often tackled by disconnected communities, conveying the latest advances as well as highlighting the limits of our current understandi...

  8. [Influence of planting density and precipitation on N2O emission from a winter wheat field].

    Science.gov (United States)

    Huang, Y; Jiang, J; Zong, L; Zhou, Q; Sass, R L; Fisher, F M

    2001-11-01

    To investigate the impact of plant density on N2O emission from winter wheat field and the cause of seasonal variation in the emission, field experiment with four planting rates of 0, 90, 180 and 270 kg/ha was conducted at the Jiangning County near Nanjing during 1999-2000 winter wheat growing season. Data of the field measurements indicated that the N2O emission rates during the season from planting to overwintering were not influenced by the plant density, while the emission was positively correlated with the planting density during the season from turning green to maturity. The emissions from the field plots with planting rates of 0 and 90 kg/ha were not found to be significantly different. A further analysis suggested that the seasonal variation of N2O emission be mainly influenced by precipitation, which could be quantitatively described by an exponential function of a weighted average precipitation of 6-day period before measurement.

  9. Assessing the value of multi-receiver low-frequency electromagnetic-induction (EMI) measurement for assessing variation in soil moisture content in field experiments with winter wheat (Triticum aestivum)

    Science.gov (United States)

    Shanahan, Peter; Binley, Andrew; Dodd, Ian; Whalley, Richard; Watts, Chris; Ashton, Rhys; Ober, Eric

    2014-05-01

    In large plant breeding field trials with multiple genotypes, measuring soil water status (an indicator of crop water uptake) by conventional techniques (e.g. core extraction and penetration resistance) is limited by the cost and effort needed to achieve sufficient replication to apply robust statistical analysis. Geophysical methods may provide a more cost-effective means of more assessing valuable information about soil water status for such studies. We present here results from a field experiment using geophysical techniques for remote mapping of soil water content on sandy loam and silt loam soils in spring/summer 2013 in the UK. The aim of the study was to assess electromagnetic-induction (EMI) conductivity measurements for sensitivity to variations in shallow soil electrical properties and the spatial and temporal mapping of soil water. The CMD Mini-Explorer (GF Instruments) operates with three receiver coils at fixed distances from a transmitter coil (0.32 m, 0.71 m, 1.2 m). Measurement of magnetic field quadrature in horizontal coplanar (HC) and vertical coplanar (VC) of the three receiver coils provides six depths of investigation for the given coil spacing cumulative sensitivities. At the two field sites the instrument was applied to measuring apparent electrical conductivity (ECa) below 7.0 x 1.8 m plots consisting of 23 rain fed winter wheat cultivars and bare soil fallow control plots. These plots were sown in March 2013 and organised into a randomised block design. Electrical resistivity tomography (ERT) surveys along 15 m transects were also conducted at the two sites in order to compare EMI measured ECa. Our results show that progressive soil drying at both sites due to crop uptake significantly decreased (pwater uptake between cultivars was found to be significant (pwheat cultivars, providing data on soil ECa with minimal user requirements and instrument error. Differences in soil ECa as a result of crop water uptake was, however, not fully

  10. Winter flooding of California rice fields reduces immature populations of Lissorhoptrus oryzophilus (Coleoptera: Curculionidae) in the spring.

    Science.gov (United States)

    Aghaee, Mohammad-Amir; Godfrey, Larry D

    2017-07-01

    In California, rice fields are flooded over the winter months (November to March) to facilitate degradation of post-harvest rice straw and to provide temporary habitat for migratory waterfowl. Prior research showed that winter flood rice fields had fewer rice water weevil (Lissorhoptrus oryzophilus), larvae and pupae during the rice production season than fields that were left unflooded in the winter. A series of experiments were conducted to provide further support for these trends under controlled conditions and to find a mechanism for this phenomenon. Under winter flooded conditions there was a 50% reduction in populations of weevil immatures compared with the untreated control (no straw or winter flood). These same conditions corresponded to a 20% increase in the amount of silicon found in plant tissues in 2014 and a 39 to 90% decrease in methane production in the soil from 2013 to 2014, respectively. Evidence from previous field research and these controlled studies supports winter flooding as an appropriate tactic for controlling L. oryzophilus populations in the spring. However, the mechanism that would explain why winter flooding adversely affects L. oryzophilus immatures remains unclear. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Wake field acceleration experiments

    International Nuclear Information System (INIS)

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics? I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs

  12. Wake field acceleration experiments

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics. I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs.

  13. Subsurface drainage to enable the cultivation of winter crops in consolidated paddy fields in Northern Iran

    NARCIS (Netherlands)

    Jafari-Talukolaee, Mehdi; Ritzema, Henk; Darzi-Naftchali, Abdullah; Shahnazari, Ali

    2016-01-01

    Subsurface drainage is a prerequisite to grow winter crops in the consolidated paddy fields in Northern Iran. A four-year study (2011-2015) was conducted to quantify the effects of subsurface drainage on the saturated hydraulic conductivity, water table, drain discharge and winter crop yields.

  14. Large-scale evaluation of pea (Pisum sativum L. germplasm for cold tolerance in the field during winter in Qingdao

    Directory of Open Access Journals (Sweden)

    Xiaoyan Zhang

    2016-10-01

    Full Text Available As a cool-season crop, pea (Pisum sativum L. can tolerate frost at the vegetative stage but experiences yield loss when freezing stress occurs at the reproductive stage. Cold-tolerance improvement of pea varieties is important for stable yield and expansion of the winter pea planting area. Under natural low-temperature conditions during winter in Qingdao, Shandong, China, we evaluated the cold tolerance of 3672 pea germplasm accessions in the field and categorized them as displaying high resistance (214, moderate resistance (835, or susceptibility (2623. The highly and moderately resistant genotypes were validated in the following year. We found that genotypes from the winter production region showed higher cold tolerance than genotypes from the spring production region. The accessions identified as having high levels of cold tolerance are recommended as potential genetic resources in cold-tolerance breeding of pea.

  15. The injury experience at the 2010 winter paralympic games.

    Science.gov (United States)

    Webborn, Nick; Willick, Stuart; Emery, Carolyn A

    2012-01-01

    The objective of this study was to examine incidence proportion and the characteristics of athlete injuries sustained during the 2010 Vancouver Paralympic Games. Descriptive epidemiological study. All medical venues at the 2010 Vancouver Paralympic Games, Canada. A total of 505 athletes from 44 National Paralympic Committees participating in the 2010 Vancouver Winter Paralympic Games. Baseline covariates included sport specificity (ie, ice sledge hockey, alpine skiing, Nordic skiing, wheelchair curling), gender, age, and disability classification. All injuries that occurred during the 2010 Vancouver Paralympic Games. "Injury" was defined as any sport-related musculoskeletal complaint that caused the athlete to seek medical attention during the study period, regardless of the athlete's ability to continue with training or competition. The Injury Surveillance System identified a total of 120 injuries among 505 athletes [incidence proportion = 23.8% (95% confidence interval, 20.11-27.7)] participating in the 2010 Winter Paralympic Games. There was a similar injury incidence proportion among male (22.8%) and female (26.6%) athletes [incidence rate ratio = 1.1 (95% confidence interval, 0.7-1.7)]. Medical encounters for musculoskeletal complaints were generated in 34% of all sledge hockey athletes, 22% of alpine ski racers, 19% of Nordic skiers, and 18% of wheelchair curling athletes. The Injury Surveillance System identified sport injuries in 24% of all athletes participating in the 2010 Winter Paralympic Games. The injury risk was significantly higher than during the 2002 (9.4%) and 2006 (8.4%) Winter Paralympic Games. This may reflect improved data collection systems but also highlights the high risk of acute injury in alpine skiing and ice sledge hockey at Paralympic Games. These data will assist future Organizing Committees with the delivery of medical care to athletes with a disability and guide future injury prevention research.

  16. Road verges and winter wheat fields as resources for wild bees in agricultural landscapes

    DEFF Research Database (Denmark)

    Henriksen, Casper Christian I; Langer, Vibeke

    2013-01-01

    had a strong positive effect in both road verges and wheat fields on the density of high value bee plants. This was due to the absence of herbicides and to practices inherent to organic farming systems, such as the use of clover (a high value bee plant) as a green manure and fodder crop.......The effects of farming system on plant density and flowering of dicotyledonous herbs of high value for bees were investigated in 14 organic and 14 conventional winter wheat fields and adjacent road verges. The organic and conventional winter wheat fields/road verges were paired based...... on the percentage of semi-natural habitats in the surrounding landscape at 1-km scale. Mean density of high value bee plants per Raunkiaer circle was significantly higher in organic winter wheat fields and their adjacent road verges than in their conventionally farmed counterparts. The effect of organic farming...

  17. Reversed field pinch experiments

    International Nuclear Information System (INIS)

    Roberston, S.

    1991-05-01

    The Reversatron RFP is usually operated with toroidal field windings which are a continuous helix of 144 turns. These windings produce a poloidal current which is uniform around the torus. The distribution of current is fixed by the geometry so that the applied field has only an m = 0, n = 0 component. The windings cannot act to stabilize an m = 0 mode with |n| > 0 or any m = 1 mode because these modes will excite no current in the windings. It has recently been suggested that parallel connected field coils might act as a shell by forcing the flux within each winding to be the same. Coils connected in parallel must have the same voltage at their terminals and thus must enclose the same volt-seconds or flux. Data from ZT-40 show that the discharges are more quiescent when parallel or series-parallel connected windings are used

  18. [Effects of irrigation mode on winter wheat yield and water- and nutrient use efficiencies under maize straw returning to field].

    Science.gov (United States)

    Dang, Jian-you; Pei, Xue-xia; Zhang, Jing; Wang, Jiao-ai; Cao, Yong; Zhang, Ding-yi

    2011-10-01

    In 2008-2010, a field experiment was conducted to study the effects of different irrigation modes on the grain yield, dry matter translocation, water use efficiency (WUE), and nutrient use efficiency (NUE) of winter wheat under maize straw returning to the field in a semi-arid and semi-humid monsoon region of Linfen, Shanxi Province of Northwest China. Irrigation at wintering time promoted tillering, irrigation at jointing stage increased the total tiller number and the fertile spike rate per tiller, whereas irrigation at booting stage promoted the dry matter accumulation in spike and increased the 1000-kernel mass. When the irrigation was implemented at two growth stages and the second irrigation time was postponed, both the dry matter translocation to leaf and the kernels per spike increased. Irrigation twice throughout the whole growth season induced a higher NUE and higher dry matter accumulation in spike, as compared to irrigation once. The irrigation amount at wintering time and the total irrigation amount had lesser effects on the tillering and the dry matter accumulation in spike. Increasing irrigation amount at jointing stage or booting stage more benefited the nutrient uptake, dry matter accumulation and translocation, and grain WUE, which in turn made the yield-formation factors be more balance and the grain yield be higher. It was concluded that to guarantee the irrigation amount at wintering time could achieve stabilized yield, and the optimal irrigation mode was irrigation at wintering time plus an additional irrigation at jointing stage (900 m3 hm(-2)), which could satisfy the water demand of winter wheat at its mid and later growth stage and increase the WUE of grain, and realize water-saving and high-yielding cultivation.

  19. Dispersal of solitary bees and bumblebees in a winter oilseed rape field

    DEFF Research Database (Denmark)

    Calabuig, Isabel

    2000-01-01

    Dispersal distributions of solitary bees and bumblebees were studied in a winter oilseed rape field. Window-traps were placed in the rape field along a line transect perpendicular to the field edge. 19 species of solitary bees were recorded and all but four species are polylectic, including...... Brassicaceae as host-plant family. Through non-linear regression, the decline in solitary bee individuals versus distance from field edge significantly fitted a steep two-parameter exponential decay function. Activity of solitary bees was clearly highest within 30 metres from the field edge. Apparently......, solitary bees do not play any noteworthy role in the pollination of winter oilseed rape in Denmark. The traps yielded ten species of bumblebees, and a significant linear correlation was found between numbers of individuals and distance from the field edge. This result is attributed to bumblebee foraging...

  20. Root growth in field-grown winter wheat: Some effects of soil conditions, season and genotype.

    Science.gov (United States)

    Hodgkinson, L; Dodd, I C; Binley, A; Ashton, R W; White, R P; Watts, C W; Whalley, W R

    2017-11-01

    This work compared root length distributions of different winter wheat genotypes with soil physical measurements, in attempting to explain the relationship between root length density and soil depth. Field experiments were set up to compare the growth of various wheat lines, including near isogenic lines (Rht-B1a Tall NIL and Rht-B1c Dwarf NIL) and wheat lines grown commercially (cv. Battalion, Hystar Hybrid, Istabraq, and Robigus). Experiments occurred in two successive years under rain fed conditions. Soil water content, temperature and penetrometer resistance profiles were measured, and soil cores taken to estimate vertical profiles of pore distribution, and root number with the core-break method and by root washing. Root length distributions differed substantially between years. Wetter soil in 2014/2015 was associated with shallower roots. Although there was no genotypic effect in 2014/2015, in 2013/2014 the dwarf wheat had the most roots at depth. In the shallower layers, some wheat lines, especially Battalion, seemed better at penetrating non-structured soil. The increase in penetrometer resistance with depth was a putative explanation for the rapid decrease in root length density with depth. Differences between the two years in root profiles were greater than those due to genotype, suggesting that comparisons of different genotypic effects need to take account of different soil conditions and seasonal differences. We also demonstrate that high yields are not necessarily linked to resource acquisition, which did not seem to be limiting in the low yielding dwarf NIL.

  1. Data of long term atmospheric diffusion experiments (Winter, 1992)

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Takashi; Chino, Masamichi; Yamazawa, Hiromi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    1998-10-01

    The data were obtained in the long-term atmospheric diffusion experiments in the Tokai area, autumn, 1991 which were a part of the Evaluation Safety Demonstration Experiments of Environmental Radiation entrusted with the Science and Technology Agency. The experiments were conducted by JAERI in cooperation with the Japan Weather Association. The report includes tracer concentration data of surface sampling points and meteorological data. (author)

  2. Model prediction of frost tolerance as related to winter survival of wheat in Finnish field trials

    Directory of Open Access Journals (Sweden)

    A.K. BERGJORD

    2008-12-01

    Full Text Available The model FROSTOL simulates course of frost tolerance in winter wheat on a daily basis from sowing on as affected by soil temperature (2 cm, snow cover, phenological development, and a genotypic maximum level of frost tolerance (LT50. A series of cultivar trials in Finland was used to evaluate the model's ability to estimate plant survival in natural field environments during winters with differing weather conditions. Recorded survival was compared with number of intersections between the curves of simulated LT50 and the soil temperature curve for each field. A cumulative stress level (CSL was calculated based both on number of intersections and FROSTOL simulated stress levels. The correlation between CSL and field recordings was quite low. While the field trials characterize a general ability to stand various types of winter stress, FROSTOL estimates damage caused by the soil temperature regime only. However, FROSTOL simulations seemed to correspond reasonably well to field observations when low temperature was the eventual cause of damage.

  3. Review of WAG Field Experience

    DEFF Research Database (Denmark)

    Christensen, Jes Reimer; Stenby, Erling Halfdan; Skauge, A.

    2001-01-01

    from the North Sea. About 60 fields have been reviewed. Both onshore and offshore projects have been included, as well as WAG injections with hydrocarbon or nonhydrocarbon gases. Well spacing is very different from onshore projects, where fine patterns often are applied, to offshore projects, where...... well spacing is in the order of 1000 m. For the fields reviewed, a common trend for the successful injections is an increased oil recovery in the range of 5 to 10% of the oil initially in place (OIIP). Very few field trials have been reported as unsuccessful, but operational problems are often noted...... recovery by combining better mobility control and contacting unswept zones, and by leading to improved microscopic displacement. This study is a review of the WAG field experience as it is found in the literature today,(1-108) from the first reported WAG injection in 1957 in Canada to the new experience...

  4. [Effects of different mulching measures on winter wheat field soil respiration in Loess Plateau dry land region].

    Science.gov (United States)

    Guan, Qing; Wang, Jun; Song, Shu-Ya; Liu, Wen-Zhao

    2011-06-01

    A field experiment was conducted to study the effects of different mulching measures on the diurnal and seasonal variations of winter wheat field soil respiration in dry land region of Loess Plateau. Four treatments were installed, i. e., 300 kg x hm(-2) straw mulching (M300), 600 kg x hm(-2) straw mulching (M600), plastic film mulching (PM), and no mulching (CK). In all treatments, the soil respiration rate had a decreasing trend from autumn to winter, but increased rapidly after winter and peaked at jointing stage. Comparing with CK, treatments mulching promoted the soil respiration obviously from wintering to maturing stage, with significant differences between treatment PM and the others. The average soil respiration rate in treatments M300, and M600 in whole growth period was 1. 52 micromol CO2 x m(-2) x s(-1) and 1. 47 micromol CO2 x m(-2) x s(-1), being 10. 2% and 6.6% higher than the CK (1.38 micromol CO2 x m(-2) s(-1)) , respectively, and that in treatment PM was 3. 63 micromol CO2 x m(-2) x s(-1), 163% higher than CK. The diurnal variation of soil respiration rate in CK and in M300 and M600 presented a single peak curve and peaked at 12:00 and 14:00, respectively, but for PM treatment, the diurnal variation of soil respiration rate was similar with that in CK at jointing stage while presented a bimodal curve at maturing stage, with the peaks at 12:00 and 16:00, respectively. Soil respiration rate had an exponential correlation with soil temperature, and a parabolic correlation with soil moisture.

  5. [Factors influencing ammonia volatilization in a winter wheat field with plastic film mulched ridges and unmulched furrows].

    Science.gov (United States)

    Shangguan, Yu-Xian; Shi, Ri-Peng; Li, Na; Han, Kun; Li, Hui-Ke; Wang, Lin-Quan

    2012-06-01

    The objective of this experiment was to quantify ammonia volatilization from a winter wheat field with plastic film mulched-ridges and unmulched-furrows (PMRF). The trial was conducted during the 2010-2011 winter wheat growing season at Yangling, Shaanxi Province. Ammonia volatilization from the soil was measured using the closed-chamber method. The results indicated that NH3 emission losses ranged between (1.66 +/- 0.3) and (3.28 +/- 0.51) kg x hm(-2) in the PMRF treatment. In comparison, the NH3 emission loss was (4.68 +/- 0.35) kg x ha(-1) in the conventional tillage treatment (i. e., smooth soil surface). The PMRF treatment reduced NH3 emissions by 29.8 to 63.8% compared with the conventional treatment. The NH3 emission losses were equivalent to 1.9% of the applied N in the conventional practice treatment. In contrast, the losses were equivalent to only 0.3% to 0.8% of the applied N in the PMRF treatment. Ammonia emissions were greatest during the first two weeks after sowing. Emissions before winter accounted for 82% of total NH3 emission in the conventional practice treatment, but only 49% to 61% of the total NH3 emission in the PMRF treatment. The soil NH4+ -N content and the soil moisture content had direct effects on NH3 emission before winter in the conventional treatment. In thePMRF treatment, the soil NH4+ -N content had a direct effect on NH3 emission before winter, whereas soil surface temperature and soil moisture had indirect effects. Ammonia emissions after the greening stage were mainly influenced by the soil NH4+ -N content. Simulation results indicated that logarithmic functions best described cumulative NH3 emission in the PMRF + high N rate treatment and the conventional treatment. A linear function best described cumulative NH3 emission in the PMRF + low N rate treatment and the unfertilized treatment. In conclusion, the PMRF treatment can significantly reduce N losses from winter wheat fields by changing the spatial-temporal dynamics of soil

  6. Modeling winter ozone episodes near oil and natural gas fields in Wyoming

    Science.gov (United States)

    Wu, Yuling; Rappenglück, Bernhard; Pour-Biazar, Arastoo; Field, Robert A.; Soltis, Jeff

    2017-04-01

    Wintertime ozone episodes have been reported in the oil and natural gas (O&NG) producing fields in Uintah Basin, Utah and the Upper Green River Basin (UGRB) in Wyoming in recent years. High concentrations of ozone precursors facilitated by favorable meteorological conditions, including low wind and shallow boundary layer (BL), were found in these episodes, although the exact roles of these precursor species in different O&NG fields are to be determined. Meanwhile, snow cover is also found to play an important role in these winter ozone episodes as the cold snow covered surface enhances the inversion, further limits the BL and the high snow albedo greatly boosts photolysis reactions that are closely related to ozone chemistry. In this study, we utilize model simulation to explore the role of chemical compositions, in terms of different VOC groups and NOx, and that of the enhanced photolysis due to snow cover in the UGRB ozone episodes in the late winter of 2011.

  7. Could behaviour and not physiological thermal tolerance determine winter survival of aphids in cereal fields?

    Directory of Open Access Journals (Sweden)

    Lucy Alford

    Full Text Available Traits of physiological thermotolerance are commonly measured in the laboratory as predictors of the field success of ectotherms at unfavourable temperatures (e.g. during harsh winters, heatwaves, or under conditions of predicted global warming. Due to being more complicated to measure, behavioural thermoregulation is less commonly studied, although both physiology and behaviour interact to explain the survival of ectotherms. The aphids Metopolophium dirhodum, Rhopalosiphum padi and Sitobion avenae are commercially important pests of temperate cereal crops. Although coexisting, these species markedly differ in winter success, with R. padi being the most abundant species during cold winters, followed by S. avenae and lastly M. dirhodum. To better understand the thermal physiology and behavioural factors contributing to differential winter success, the lethal temperature (physiological thermotolerance and the behaviour of aphids in a declining temperature regime (behavioural thermotolerance of these three species were investigated. Physiological thermotolerance significantly differed between the three species, with R. padi consistently the least cold tolerant and S. avenae the most cold tolerant. However, although the least cold tolerant of the study species, significantly more R. padi remained attached to the host plant at extreme sub-zero temperatures than S. avenae and M. dirhodum. Given the success of anholocyclic R. padi in harsh winters compared to its anholocyclic counterparts, this study illustrates that behavioural differences could be more important than physiological thermotolerance in explaining resistance to extreme temperatures. Furthermore it highlights that there is a danger to studying physiological thermotolerance in isolation when ascertaining risks of ectotherm invasions, the establishment potential of exotic species in glasshouses, or predicting species impacts under climate change scenarios.

  8. Nuclide-migration field experiments

    International Nuclear Information System (INIS)

    Erdal, B.R.; Wolfsberg, K.; Johnstone, J.K.; Erickson, K.L.; Friedman, A.M.; Fried, S.; Hines, J.J.

    1981-03-01

    When considering groundwater flow and radionuclide retention in the complex flow systems that can occur in geologic formations, one has a serious problem in determining if laboratory studies are being performed under conditions appropriate to natural systems. This document is the project plan for a program designed to begin to address these problems. The project is being carried out jointly by the Los Alamos National Laboratory, Sandia National Laboratories, and Argonne National Laboratory. The work has three principal objectives: (1) to develop the experimental, instrumental, and safety techniques necessary to conduct controlled, small-scale radionuclide migration field experiments, including those involving actinides; (2) to use these techniques to define radionuclide migration through rock by performing generic, at-depth experiments under closely monitored conditions; and (3) to determine whether available lithologic, geochemical, and hydrologic properties together with existing or developing transport models are sufficient and appropriate to describe real field conditions

  9. Returning Winter Cover Crop Residue Influences Soil Aggregation and Humic Substances under Double-cropped Rice Fields

    Directory of Open Access Journals (Sweden)

    Haiming Tang

    2017-11-01

    Full Text Available ABSTRACT Residue management in cropping systems may improve soil quality. However, there are few studies on the effects of residue management on soil aggregation and carbon content in the humin (C-HUM, humic acid (C-HAF and fulvic acid (C-FAF fractions in South China. Therefore, the effects on soil aggregation and on the C-HUM, C-HAF, C-FAF from incorporating winter cover crop residues in a double-cropped rice (Oryza sativa L. system in South China fields were studied. The experiment has been conducted since winter 2004. Five winter cropping systems were used: rice-rice-ryegrass (Ry-R-R, rice-rice-Chinese milk vetch (Mv-R-R, rice-rice-potato (Po-R-R, rice-rice-rape (Ra-R-R and rice-rice with winter fallow (Fa-R-R. The results indicated that the organic C content in the paddy soil under the Ry-R-R, Mv-R-R, Po-R-R, and Ra-R-R systems was significantly higher than the content in the Fa-R-R system at the early rice and late rice maturity stages. The different sizes of aggregates under the five treatments showed similar trends. The Po-R-R systems had the highest percentage of soil aggregates in each size class and the Fa-R-R systems had the lowest percentage of soil aggregates in each size class in the 0.00-0.05, 0.05-0.10, and 0.10-0.20 m soil depth at the early rice and late rice maturity stages. The C-HUM, C-HAF, and C-FAF increased through long-term application of winter cover crop residues. Statistical analysis showed that the C-HAF under the Ra-R-R systems was significantly higher than that in the Fa-R-R systems at the early rice and late rice maturity stages. The C-FAF and C-HUM under the Mv-R-R systems was significantly higher than the C-FAF and C-HUM in the Fa-R-R systems at the early rice and late rice maturity stages. As a result, the soil organic C content, the soil aggregates in each size class, and the C-HUM, C-HAF, and C-FAF increased from application of winter cover crop residues in double-cropped rice systems.

  10. Evapotranspiration and its partitioning in an irrigated winter wheat field: A combined isotopic and micrometeorologic approach

    Science.gov (United States)

    Zhang, Yucui; Shen, Yanjun; Sun, Hongyong; Gates, John B.

    2011-10-01

    SummaryGroundwater overdraft threatens the future of irrigated agriculture in the North China Plain. Because irrigated winter wheat is the dominant user of extracted groundwater, improved understanding of water cycling through the soil-plant-atmosphere continuum during wheat cultivation in the North China Plain is necessary for improving the sustainable utilization of limited water resources and promoting food security. In this paper, a combination of micrometeorological and stable isotope techniques was used to investigate evapotranspiration and soil water dynamics in a typical winter wheat agro-ecosystem (Luancheng Agro-ecosystem Experiment Station, Hebei Province). Stable isotope mixing models were used with eddy covariance evapotranspiration estimates and micro-lysimeter evaporation measurements to partition evapotranspiration and determine temporal variability of root water uptake depths. Results suggest that evaporation during the winter wheat irrigation season can reach up to 30% of the total water consumption (almost two typical irrigations). The main depths of root water uptake were 0-40 cm. Therefore, it is suggested that the planned irrigation wetting depth can be reduced at least to 40 cm, rather than the traditional 100 cm, as a means of water conservation. Widespread implementation of these practices could amount to a significant water savings for the North China Plain.

  11. A model for making field-based nitrogen recommendations for winter wheat in western oregon

    International Nuclear Information System (INIS)

    Baloch, D.M.; Malghani, M.A.K.; Khan, M.A.; Kakar, E.

    2010-01-01

    A model based on early spring soil and tissue analysis was developed and evaluated for predicting the need for additional nitrogen (N) fertilizer on winter wheat. To develop the model, On-farm trials were' established over three years 1994-95 in grower's fields at three different locations across the Willamette Valley of western Oregon. Two field-scale validation trials were run in 1996-97. Rotations were soft white winter wheat following grass seed, sweet corn or a legume. Four treatments, including a check receiving no nitrogen, were used at each site At the site where wheat followed corn, the predicted optimum N rate was 168 kg N ha/sup -1/ however, the 112 kg N ha/sup -1/ rate was the optimum rate predicted by the developed model. The 84 kgN ha/sup -1/ and 140 kgN ha/sup -1/ rates were selected to bracket the recommended rate (+- 28 kg N ha/sup -1/). Wheat following grass seed had high soil supplied N which depressed the yield even at moderate fertilizer N rates. The model overall accurately assess field-specific optimum fertilizer N status. (author)

  12. Influence of bird feces to water quality in paddy fields during winter season

    Science.gov (United States)

    Somura, H.; Takeda, I.; Masunaga, T.; Mori, Y.; Ide, J.

    2009-12-01

    Thousands of migratory birds such as tundra swan came to the paddy fields for overwintering in recent years in the study area. They stayed in paddy fields during night time for sleeping and used around the fields as a feeding ground during day time. During the birds stay, it was observed that water pooled in the paddy fields gradually turned green and gave off a bad smell. In this study, we tried to estimate the influence of the bird’s feces to water quality in the paddy fields. The study area is in the southeastern portion of Matsue City in Shimane Prefecture, Japan. In several paddy fields, puddling procedure was executed after harvesting rice and then water was stored in the paddy fields during winter season. This is because of being easier of farming activities such as weeding next season and of avoiding using pesticide for weeding with rising of environmental awareness. Water in the paddy fields was collected once or twice a month from the target fields and analyzed nitrogen, phosphorus, and organic carbon in 2007. In the study in 2006, as water was sampled once a week and the changes in the water quality had been grasped, we paid attention to behavior of the birds in a day in the field investigation in 2007. The number of the birds was counted once an hour from visible 7 am to 6 pm once a month. In addition to this, fresh feces were sampled from the fields and analyzed the contents of nitrogen, phosphorus, and organic carbon in the feces. As results, average water qualities of TN, TP, and TOC from November 2007 to March 2008 showed very high concentrations compared with a river water concentration used as irrigation water. More than 70% of TN in the water was ammonia nitrogen. Moreover, comparing with a standard fertilizer amount of nitrogen and phosphorus for paddy fields during irrigation period, it was estimated that the amount of nitrogen excreted by the bird’s feces during the winter season was equivalent to the standard fertilizer amount and the

  13. Field Demonstration of Automated Demand Response for Both Winter and Summer Events in Large Buildings in the Pacific Northwest

    Energy Technology Data Exchange (ETDEWEB)

    Piette, Mary Ann; Kiliccote, Sila; Dudley, Junqiao H.

    2011-11-11

    There are growing strains on the electric grid as cooling peaks grow and equipment ages. Increased penetration of renewables on the grid is also straining electricity supply systems and the need for flexible demand is growing. This paper summarizes results of a series of field test of automated demand response systems in large buildings in the Pacific Northwest. The objective of the research was two fold. One objective was to evaluate the use demand response automation technologies. A second objective was to evaluate control strategies that could change the electric load shape in both winter and summer conditions. Winter conditions focused on cold winter mornings, a time when the electric grid is often stressed. The summer test evaluated DR strategies in the afternoon. We found that we could automate both winter and summer control strategies with the open automated demand response communication standard. The buildings were able to provide significant demand response in both winter and summer events.

  14. [Winter wheat yield gap between field blocks based on comparative performance analysis].

    Science.gov (United States)

    Chen, Jian; Wang, Zhong-Yi; Li, Liang-Tao; Zhang, Ke-Feng; Yu, Zhen-Rong

    2008-09-01

    Based on a two-year household survey data, the yield gap of winter wheat in Quzhou County of Hebei Province, China in 2003-2004 was studied through comparative performance analysis (CPA). The results showed that there was a greater yield gap (from 4.2 to 7.9 t x hm(-2)) between field blocks, with a variation coefficient of 0.14. Through stepwise forward linear multiple regression, it was found that the yield model with 8 selected variables could explain 63% variability of winter wheat yield. Among the variables selected, soil salinity, soil fertility, and irrigation water quality were the most important limiting factors, accounting for 52% of the total yield gap. Crop variety was another important limiting factor, accounting for 14%; while planting date, fertilizer type, disease and pest, and water press accounted for 7%, 14%, 10%, and 3%, respectively. Therefore, besides soil and climate conditions, management practices occupied the majority of yield variability in Quzhou County, suggesting that the yield gap could be reduced significantly through optimum field management.

  15. Fertilizers nitrogen balance under maizl and winter rye in lysimentric experiments

    International Nuclear Information System (INIS)

    Ionova, O.N.

    1979-01-01

    The balance of the labelled 15 N nitrogen fertilizers in lysimentric experiment carried oUt in the turf-podsolic medium loamy soil has been studied. The results of two year experiment (1976-1977) have shown that depending on the doses and time of introduction the use of fertilizer nitrogen by maize varied from 51 to 58 % and by winter rye from 52 to 59 %. Consolidation in the organic substance of soil constituted 18-26 and 17-33 %, respectively. The losses of fertilizer nitrogen varied (14-29 % under maize and 9-23 % under winter rye). Nitrogen losses as a result of atmospheric precipitation infiltration both under maize and winter rye occured mainly at the expense of nitrogen of soil and reached considerable dimensions (31 kg) only under conditions of exceeding moistening of 1976. The losses of fertilizer nitrogen caused by washing out do not exceed 1 % for two years. The main losses of fertilizer nitrogen occurred in the form of gaseous nitrogen compounds

  16. [Effect of Irrigation Patterns on Soil CO₂ and N₂O Emissions from Winter Wheat Field in North China Plain].

    Science.gov (United States)

    Guo, Shu-fang; Qi, Yu-chun; Yin, Fei-hu; Peng, Qin; Dong, Yun-she; He, Yun-long; Yan, Zhong-qing

    2016-05-15

    The water-saving irrigation is the trend of modernized agriculture. This paper aimed to study the effect of water-saving irrigation on soil CO₂ and N₂O emissions. The field experiments were conducted under micro sprinkler irrigation of integrated water and fertilizer (MSI) and conventional flooding irrigation (FI) in winter wheat growth season in the west of North China Plain during 2013- 2014 using the static chamber method. This paper analyzed the seasonal variation of soil CO₂and N₂O emissions under MSI and FI, and then compared the soil CO₂ and N₂O emissions from treatments located in different vertical distance away from micro sprinkler pipe. Root exclusion was used to estimate the components of soil respiration and agricultural carbon sequestration intensity under MSI and FI in winter wheat field. The results indicated that: (1) The average soil CO₂ emissions under MSI and FI were 418.19 mg (m² · h)⁻¹ and 372.14 mg · (m² · h)⁻¹ respectively with no significant difference, and cumulative CO₂ emissions under MSI and FI were 2 150.6 g · m⁻² and 1 904.6 g · m⁻², respectively. (2) During returning green stage to harvest stage of winter wheat, the highest soil CO₂ cumulative emissions were found at the closest site to the micro sprinkler irrigated pipes under MSI. However, there were no significant differences among spatial treatments. (3) Under MSI and FI, soil heterotrophic respiration (C) was 468.49 g · m⁻² and 427.31 g · m⁻², and the net primary productivity (3) was 1988.21 g · m⁻² and 1770.54 g · m⁻²; the carbon sink (C) during winter wheat growing season was 1 519.72 g · m⁻² and 1 343.24 g · m⁻², respectively. (4) The average N₂O emissions under MSI and FI were 50.77 µg · (m² · h)⁻¹ and 28.81 µg · (m² · h)⁻¹ respectively with no significant difference. Cumulative N₂O emission under MSI and FI was 272.67 mg · m⁻² and 154.08 mg · m⁻², respectively. (5) During returning green

  17. Increasing weed flora in Danish beet, pea and winter barley fields

    DEFF Research Database (Denmark)

    Andreasen, Christian; Stryhn, Henrik

    2012-01-01

    In Denmark, several political initiatives have been taken to reduce use of pesticides and fertilizer in order to avoid unwanted side effect of the increasing cropping intensification. Based on two nation wide surveys we investigate flora changes and discuss the changes in relation to biodiversity......, crop yield, agricultural management and climate. Our assumption is that the surveys are representative for the country. We present frequency analyses of 90 species recorded in 157 fields surveyed in 1987e89, and in 167 fields surveyed in 2001e04. Based on 4910 circular sample plots in unsprayed areas......, we studied flora changes in four crops and showed that the frequency of many weed species have increased. Particularly some winter annual species (e.g. Veronica arvensis L. and Viola arvensis Murray), grass weeds (Poa annua L., Apera spica-venti (L.) P. Beauv.) and nitrophileous species (e...

  18. Fladis field experiments. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, M.; Ott, S.

    1996-06-01

    The objective of the Fladis field experiments was to investigate dispersion of liquefied ammonia with equal attention to the near-source aerosol jet, the intermediate heavy gas dispersion phase, and the downstream transition to passive dispersion. The present report presents the sensor layout and gives an overview of the available experimental data. This is done for observations in a fixed frame of reference and relative to the instantaneous plume centre line. The moving frame statistics are expected to compare better with wind tunnel simulations and numerical models which do not include plume meandering. The plume mass flux is estimated from the observed plume profiles and compared to the release rate. Average surface concentrations are found with a special interpolation method, and this is used to study how the averaging period affects the plume footprint. The instantaneous plume is non-Gaussian, and this is demonstrated by Lidar measurements in the far field and thermocouple measurements in the near-source jet. Probability functions and a spatial correlation for the concentration are found. The heat budget of the plume shows signs of heat flux from the ground. The composition of the liquid aerosols was observed to change from almost pure ammonia to almost pure water. A new two-dimensional `shallow layer` type model SLAM is developed, and an existing `box` type model for heavy-gas dispersion on a uniform terrain is generalized. (au) 3 tabs., 19 ills., 29 refs.

  19. Apps for Angiosperms: The Usability of Mobile Computers and Printed Field Guides for UK Wild Flower and Winter Tree Identification

    Science.gov (United States)

    Stagg, Bethan C.; Donkin, Maria E.

    2017-01-01

    We investigated usability of mobile computers and field guide books with adult botanical novices, for the identification of wildflowers and deciduous trees in winter. Identification accuracy was significantly higher for wildflowers using a mobile computer app than field guide books but significantly lower for deciduous trees. User preference…

  20. Polarized Imaging Nephelometer Scattering Measurements from the Winter of 2013 Discover-AQ Field Mission

    Science.gov (United States)

    Espinosa, R.; Martins, J.; Dolgos, G.; Dubovik, O.; Ziemba, L. D.; Beyersdorf, A. J.

    2013-12-01

    After greenhouse gases, aerosols are thought to have the largest contribution to the total radiative forcing of the atmosphere, but they are frequently cited as the single largest source of uncertainty among all anthropogenic radiative forcing components. Remote sensing allows global measurements of aerosol properties, however validation of these measurements are crucial, and their retrieval algorithms require climatological assumptions that must be first measured in situ. In situ instruments are also needed to supplement remote sensing measurements, which frequently have a relatively low spatial resolution, particularly when assessing surface air quality. The Laboratory for Aerosols, Clouds and Optics (LACO) at the University of Maryland Baltimore County (UMBC) has developed an instrument called the Polarized Imaging NEPHelometer (PI-Neph) to significantly aid in situ particle optical scattering measurements. The PI-Neph is based on a novel polar nephelometer design that uses a high-powered laser and wide field of view optical detection system (CCD camera) to measure the intensity of scattered laser light as a function of scattering angle. This allows for the measurement of scattering coefficient, phase function and polarized phase function over an angular range of 2 to 178 degrees with an angular resolution of less than half of a degree. This simple layout also permits the construction of an instrument that is compact enough to be flown on a variety of airborne platforms. PI-Neph measurements have been validated by a variety of methods since its completion in the fall of 2011. Measurements of mono-disperse polystyrene spheres have yielded results that are in close agreement with Mie theory, while scattering coefficient measurements made in parallel with commercially available integrating nephelometers from TSI have agreed to within 5%. The PI-Neph has successfully participated in several field experiments, most recently completing the January/February portion of

  1. [Effects of mulching and fertilization on winter wheat field soil moisture in dry highland region of Loess Plateau].

    Science.gov (United States)

    Wang, Xiao-Feng; Tian, Xiao-Hong; Chen, Zi-Hui; Chen, Hui-Lin; Wang, Zhao-Hui

    2009-05-01

    A field experiment was conducted in a winter wheat field in Weibei dry highland region of Loess Plateau to study the effects of different mulching and fertilization treatments on soil moisture regime. The treatments were 1) no fertilization, 2) conventional fertilization, 3) recommended fertilization, 4) recommended fertilization + manure, 5) recommended fertilization + plastic mulch on soil ridges, 6) recommended fertilization + plastic mulch on soil ridges and straw mulch in furrows, and 7) recommended fertilization + straw mulch on entire plot. Soil moisture content was determined regularly with a neutron probe. Among the treatments, recommended fertilization plus plastic mulch on soil ridges and straw mulch in furrows in dry season (spring) resulted in the greatest increase of soil water storage and maintained the storage to the critical stage crops needed, followed by recommended fertilization plus plastic mulch on soil ridges. These two treatments could store more precipitation in field, and would benefit the development of rainfed agriculture in dry highland region of Loess Plateau. As for recommended fertilization plus manure, it had the least increase of soil water storage, with a difference of 48.2 mm to the recommended fertilization plus plastic mulch on soil ridges and straw mulch in furrows in dry season.

  2. Stemflow affects spatial soil moisture fields differently in summer and winter

    Science.gov (United States)

    Hildebrandt, Anke; Friesen, Jan; Kögler, Simon

    2014-05-01

    Stemflow is only a minor component of net precipitation, but because it acts as a point input, it has the potential to strongly shape the soil moisture patterns below trees and induce vertical fluxes as well as groundwater recharge. However, there is little research on the evolution of soil moisture patterns around trees over prolonged periods of time. In this paper we investigate in a beech dominated forest in central Germany the dynamics of surface soil moisture in proximal (radius around the tree trunks. Data were collected over a nine months period, including 10 weeks of intensive event based throughfall and stemflow monitoring. During the growing season, water content near the tree trunks was almost always lower compared to greater distance from the tree, which may be related to both lower root water uptake and higher throughfall in regions with thinner crowns at mid-distance between trees. During the growing season, soil water content near the beech trees only exceeded levels at greater distance during few rain events with substantial stemflow (15-20% of rain). However, during the wintertime, soil moisture near the trees was higher than at greater distances, in particular in response to rain events after leaf senescence. The variance of soil moisture at tree-distant locations is highest at intermediate mean moisture levels, while variance is low at both very high and very low mean soil water content. No such pattern is evident for the region near the trees, where both the highest and lowest variances occur at intermediate soil water contents. Our results indicate that the areas near tree trunks are a source of substantial spatial variation in the soil moisture field below trees. The elevated soil moisture in fall and early winter suggests a strong role of stemflow for shaping soil moisture patterns during mild winter periods.

  3. Changes in the status of harvested rice fields in the Sacramento Valley, California: Implications for wintering waterfowl.

    Science.gov (United States)

    Miller, Michael R.; Garr, Jay D.; Coates, Peter S.

    2010-01-01

    Harvested rice fields provide critical foraging habitat for wintering waterfowl in North America, but their value depends upon post-harvest treatments. We visited harvested ricefields in the Sacramento Valley, California, during the winters of 2007 and 2008 (recent period) and recorded their observed status as harvested (standing or mechanically modified stubble), burned, plowed, or flooded. We compared these data with those from identical studies conducted during the 1980s (early period). We documented substantial changes in field status between periods. First, the area of flooded rice increased 4-5-fold, from about 15% to >40% of fields, because of a 3-4-fold increase in the percentage of fields flooded coupled with a 37-41% increase in the area of rice produced. Concurrently, the area of plowed fields increased from 35% of fields, burned fields declined from about 40% to 1%, and fields categorized as harvested declined from 22-54% to harvested.We encourage waterfowl managers to implement a rice field status survey in the Sacramento Valley and other North American rice growing regions as appropriate to support long-term monitoring programs and wetland habitat conservation planning for wintering waterfowl.

  4. Impact of sensor-controlled variable-rate fungicide application on yield, senescence and disease occurrence in winter wheat fields.

    Science.gov (United States)

    Tackenberg, Maria; Volkmar, Christa; Schirrmann, Michael; Giebel, Antje; Dammer, Karl-Heinz

    2017-12-28

    Field experiments examining target-oriented variable-rate fungicide spraying were performed in 2015 and 2016. The spray volume was adapted in real time to the local green coverage level of winter wheat (Triticum aestivum L.), which was detected using a camera sensor. Depending on the growth heterogeneity in the three strip trials in 2015, fungicide savings in the sensor-sprayed strip compared with the adjacent uniformly sprayed strip were 44%, 45% and 1%. In the 2016 field trial, the saving was 12%. There was no greater level of senescence or disease occurrence, and no higher yield losses in the camera-controlled variable-rate sprayed strips compared with the adjacent uniformly sprayed strips. From an ecological and economical point of view, sensor-controlled variable-rate spraying technology, which uses the level of green crop coverage as the plant parameter to adapt the spray volume locally, can be an alternative to the common practice of uniform spraying. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  5. Inversion techniques in radar remote sensing of agricultural field : case studies on sugar beet and winter wheat

    NARCIS (Netherlands)

    Rijckenberg, G.J.

    1997-01-01

    This thesis is an attempt to gain insight in the retrieval of the soil moisture content and the vegetation water content from the radar backscatter of agricultural fields. Two crops have been selected: sugar beet and winter wheat. For a retrieval of the two agricultural parameters two

  6. Evaluating the potential nitrogen savings without yield loss using variable nitrogen application strategies in a heterogeneous winter wheat field

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Nyholm; Sørensen, Claus Aage Grøn; Søgaard, Henning Tangen

    During a single growth season, a plot trial was carried out in a selected heterogeneous field in Denmark in an attempt to estimate the optimal variable nitrogen rate applied to winter wheat. 61 Nitrogen/grain yield dose–response curves were estimated using five nitrogen application rates (30, 90,...

  7. Nitrous oxide emission from highland winter wheat field after long-term fertilization

    Directory of Open Access Journals (Sweden)

    X. R. Wei

    2010-10-01

    Full Text Available Nitrous oxide (N2O is an important greenhouse gas. N2O emissions from soils vary with fertilization and cropping practices. The response of N2O emission to fertilization of agricultural soils plays an important role in global N2O emission. The objective of this study was to assess the seasonal pattern of N2O fluxes and the annual N2O emissions from a rain-fed winter wheat (Triticum aestivum L. field in the Loess Plateau of China. A static flux chamber method was used to measure soil N2O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N2O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK, manure (M, nitrogen (N, nitrogen + phosphorus (NP, and nitrogen + phosphorus + manure (NPM. Soil N2O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, m slightly increased N2O flux while N, NP and NPM treatments significantly increased N2O fluxes. The fertilizer induced increase in N2O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N2O flux. N2O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N2O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK. Mineral and manure

  8. Nitrous oxide emission from highland winter wheat field after long-term fertilization

    Science.gov (United States)

    Wei, X. R.; Hao, M. D.; Xue, X. H.; Shi, P.; Horton, R.; Wang, A.; Zang, Y. F.

    2010-10-01

    Nitrous oxide (N2O) is an important greenhouse gas. N2O emissions from soils vary with fertilization and cropping practices. The response of N2O emission to fertilization of agricultural soils plays an important role in global N2O emission. The objective of this study was to assess the seasonal pattern of N2O fluxes and the annual N2O emissions from a rain-fed winter wheat (Triticum aestivum L.) field in the Loess Plateau of China. A static flux chamber method was used to measure soil N2O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N2O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK), manure (M), nitrogen (N), nitrogen + phosphorus (NP), and nitrogen + phosphorus + manure (NPM). Soil N2O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, m slightly increased N2O flux while N, NP and NPM treatments significantly increased N2O fluxes. The fertilizer induced increase in N2O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N2O flux. N2O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N2O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK). Mineral and manure nitrogen fertilizer enhanced N2O emissions in wetter years compared to dryer years. Phosphorous fertilizer offset 0.50 and 1.26 kg N2O-N ha-1 increases, while manure + phosphorous offset 0

  9. Winter Irrigation Effects in Cotton Fields in Arid Inland Irrigated Areas in the North of the Tarim Basin, China

    Directory of Open Access Journals (Sweden)

    Pengnian Yang

    2016-02-01

    Full Text Available Winter irrigation is one of the water and salt management practices widely adopted in arid irrigated areas in the Tarim Basin located in the Xinjiang Uygur Autonomous Region in the People’s Republic of China. A winter irrigation study was carried out from November 2013 to March 2014 in Korla City. A cotton field was divided into 18 plots with a size of 3 m × 3 m and five winter irrigation treatments (1200 m3/ha, 1800 m3/ha, 2400 m3/ha, 3000 m3/ha, and 3600 m3/ha and one non-irrigation as a control were designed. The results showed that the higher winter irrigation volumes allowed the significant short-term difference after the irrigation in the fields with the higher soil moisture content. Therefore, the soil moisture in the next sowing season could be maintained at the level which was slightly lower than field capacity and four times that in the non-irrigation treatment. The desalination effect of winter irrigation increased with the increase of water irrigation volume, but its efficiency decreased with the increase of water irrigation volume. The desalination effect was characterized by short-term desalination, long-term salt accumulation, and the time-dependent gradually decreasing trend. During the winter irrigation period, air temperature was the most important external influencing factor of the soil temperature. During the period of the decrease in winter temperatures from December to January, soil temperature in the 5-cm depth showed no significant difference in all the treatments and the control. However, during the period of rising temperatures from January to March, soil temperature in the control increased significantly, faster than that in all treatments. Under the same irrigation volume, the temperature difference between the upper soil layer and the lower soil layer increased during the temperature drop period and decreased during the temperature rise period. In this paper, we proposed the proper winter irrigation volume of 1800

  10. Nitrogen reserves, spring regrowth and winter survival of field-grown alfalfa (Medicago sativa) defoliated in the autumn.

    Science.gov (United States)

    Dhont, Catherine; Castonguay, Yves; Nadeau, Paul; Bélanger, Gilles; Drapeau, Raynald; Laberge, Serge; Avice, Jean-Christophe; Chalifour, François-P

    2006-01-01

    The objective of the study was to characterize variations in proline, arginine, histidine, vegetative storage proteins, and cold-inducible gene expression in overwintering roots of field-grown alfalfa, in response to autumn defoliation, and in relation to spring regrowth and winter survival. Field trials, established in 1996 in eastern Canada, consisted of two alfalfa cultivars ('AC Caribou' and 'WL 225') defoliated in 1997 and 1998 either only twice during the summer or three times with the third defoliation taken 400, 500 or 600 growing degree days (basis 5 degrees C) after the second summer defoliation. The root accumulation of proline, arginine, histidine and soluble proteins of 32, 19 and 15 kDa, characterized as alfalfa vegetative storage proteins, was reduced the following spring by an early autumn defoliation at 400 or 500 growing degree days in both cultivars; the 600-growing-degree-days defoliation treatment had less or no effect. Transcript levels of the cold-inducible gene msaCIA, encoding a glycine-rich protein, were markedly reduced by autumn defoliation in 'WL 225', but remained unaffected in the more winter-hardy cultivar 'AC Caribou'. The expression of another cold-inducible gene, the dehydrin homologue msaCIG, was not consistently affected by autumn defoliation. Principal component analyses, including components of root organic reserves at the onset of winter, along with yield and plant density in the following spring, revealed that (a) amino acids and soluble proteins are positively related to the vigour of spring regrowth but poorly related to winter survival and (b) winter survival, as indicated by plant density in the spring, is associated with higher concentrations of cryoprotective sugars in alfalfa roots the previous autumn. An untimely autumn defoliation of alfalfa reduces root accumulation of specific N reserves such as proline, arginine, histidine and vegetative storage proteins that are positively related to the vigour of spring

  11. Evaluating the relationship between biomass, percent groundcover and remote sensing indices across six winter cover crop fields in Maryland, United States

    Science.gov (United States)

    Prabhakara, Kusuma; Hively, W. Dean; McCarty, Gregory W.

    2015-07-01

    Winter cover crops are an essential part of managing nutrient and sediment losses from agricultural lands. Cover crops lessen sedimentation by reducing erosion, and the accumulation of nitrogen in aboveground biomass results in reduced nutrient runoff. Winter cover crops are planted in the fall and are usually terminated in early spring, making them susceptible to senescence, frost burn, and leaf yellowing due to wintertime conditions. This study sought to determine to what extent remote sensing indices are capable of accurately estimating the percent groundcover and biomass of winter cover crops, and to analyze under what critical ranges these relationships are strong and under which conditions they break down. Cover crop growth on six fields planted to barley, rye, ryegrass, triticale or wheat was measured over the 2012-2013 winter growing season. Data collection included spectral reflectance measurements, aboveground biomass, and percent groundcover. Ten vegetation indices were evaluated using surface reflectance data from a 16-band CROPSCAN sensor. Restricting analysis to sampling dates before the onset of prolonged freezing temperatures and leaf yellowing resulted in increased estimation accuracy. There was a strong relationship between the normalized difference vegetation index (NDVI) and percent groundcover (r2 = 0.93) suggesting that date restrictions effectively eliminate yellowing vegetation from analysis. The triangular vegetation index (TVI) was most accurate in estimating high ranges of biomass (r2 = 0.86), while NDVI did not experience a clustering of values in the low and medium biomass ranges but saturated in the higher range (>1500 kg/ha). The results of this study show that accounting for index saturation, senescence, and frost burn on leaves can greatly increase the accuracy of estimates of percent groundcover and biomass for winter cover crops.

  12. Field Experiments of Family Planning Incentives.

    Science.gov (United States)

    Rogers, Everett M.

    A review of four quasi-experiments on family planning incentives in three Asian nations is presented, and a multi-national comparative field experiment on family planning incentives is proposed. Experiments include: (1) The Ernakulam vasectomy campaigns, (2) Indian Tea Estates retirement bond incentive program, (3) Taiwan educational bond…

  13. Torino 2006. XX Olympic and IX Paralympic Winter Games: the ENT experience.

    Science.gov (United States)

    Succo, G; Crosetti, E; Mattiazzo, A; Riontino, E; Massazza, G

    2008-06-01

    A total of 27 competition days, more than 3000 athletes, over 10,000 components of the Olympic family, 3,500 workers, 2,500 volunteers, an overall business of more than 2 billion Euros. These, in a nutshell, are just a few of the data concerning the XX Olympic and the IX Paralympic Winter Games, Torino, Italy, 2006. Such a huge event, obviously required a meticulously organized medical service to cope with the healthcare of the athletes, official workers and the Olympic family, distributed over a geographic area of approximately 80 km in diameter. An ENT service was organized within the medical service, which was divided between 3 Polyclinics, in which 12 ENT Specialists were on duty. The present report gives an account of the final data concerning the service involved, together with a description of the approach used in the actual organization, with a view to providing useful information for colleagues who will be called upon, for a similar service, in future Olympic Winter Games. The ENT healthcare offered was confirmed to be proportional to the requirements, both from a qualitative and quantitative point of view. All the ENT specialists involved, reported having gained an immense store of human experience from having lived the Olympic atmosphere as a volunteer exerting one's own profession. The facilities available in the Polyclinics, which were at a considerable distance from the Hospital, were found to be more than adequate with respect to the pathological conditions and service requested, particularly in 17% of the cases which would otherwise have been sent to a Hospital Outpatient Unit at least 80 km away.

  14. Shallow tillage generates higher N2O emissions: results of continuous chamber-based measurement in a winter wheat field.

    Science.gov (United States)

    Broux, François; Lognoul, Margaux; Theodorakopoulos, Nicolas; Hiel, Marie-Pierre; Bodson, Bernard; Heinesch, Bernard; Aubinet, Marc

    2017-04-01

    Agriculture is one of the most important contributors to GHG emission, notably through fertilized croplands. Though, few publications have studied simultaneously and through continuous measurement the N2O and CO2 emissions in cultivated lands. We conducted this study to assess the effect of farming practices and climate on both N2O and CO2 emissions from a winter wheat crop. The experiment was held in an experimental field in the loamy region in Belgium from March 2016 till crop harvest in August 2016. The fluxes were measured on two nearby parcels in a winter wheat field with restitution of the residues from previous crop. For the past 8 years, one parcel was subjected to a shallow tillage (ST, 10 cm depth) and the other one to a conventional tillage (CT, 25 cm depth). On each parcel, the emissions are assessed with homemade automated closed chambers. Measurement continuity and good temporal resolution (one mean flux every 4 hours) of the system allowed a fine detection and quantification of the emission peaks which usually represent the major part of N2O fluxes. In addition to gas fluxes, soil water content and temperature were measured continuously. Soil samples were taken regularly to determine soil pH, soil organic carbon and nitrogen pools (total, NO3- and NH4+) and study microbial diversity and nitrification/denitrification gene expression. Unexpectedly, results showed N2O emissions twice as large in the ST parcel as in the CT parcel. On the contrary, less important CO2 emissions were observed under ST. Several emission peaks of N2O were observed during the measurement period. The peaks occurred after fertilization events and seemed to be triggered by an elevation of soil water content. Interesting links could be made between soil NH4-N and NO3-N pools and N2O emissions. Nitrification being the main process originating the fluxes was suggested on the one hand by the temporal evolution of nitrogen pools and N2O emissions and on the other hand by the relation

  15. Field Experience Study in a Traditional Setting.

    Science.gov (United States)

    Perenich, Theresa A.

    1978-01-01

    A field experience in fashion marketing for Kansas State University students is described. The functions and responsibilities of the coordinator, the student, and the departmental supervisor are outlined, along with the evaluation processes used. (Author/LBH)

  16. A Field Experiment in Motivating Employee Ideas

    NARCIS (Netherlands)

    M. Gibbs (Michael); S. Neckermann (Susanne); C. Siemroth (Christoph)

    2014-01-01

    markdownabstract__Abstract__ We study the effects of a field experiment designed to motivate employee ideas, at a large technology company. Employees were encouraged to submit ideas on process and product improvements via an online system. In the experiment, the company randomized 19 account

  17. Field experiments on airborne moisture transport

    NARCIS (Netherlands)

    Oldengarm, J.; Gids, W.F. de

    1990-01-01

    Within the framework of the Dutch participation in the IEA Annex XIV “Condensation” field experiments have been carried out to study airbome moisture transport in realistic circumstances. The experiments were done in an unoccupied 3-story dwelling in Leidschendam in the Netherlands. Some of the

  18. Overview of Field Experience - Degradation Rates & Lifetimes

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Dirk; Kurtz, Sarah

    2015-09-14

    The way a PV module fails may depend not only on its design and the materials used in its construction, but also on the weather it experiences, the way it is mounted, and the quality control during its manufacture. This presentation gives an overview of Field Experience - what degradation rates and what lifetimes are being observed in various regions.

  19. Field measurements of the ambient ozone formation potential in Beijing during winter

    Science.gov (United States)

    Crilley, Leigh; Kramer, Louisa; Thomson, Steven; Lee, James; Squires, Freya; Bloss, William

    2017-04-01

    The air quality issues in Beijing have been well-documented, and the severe air pollution levels result in a unique chemical mix in the urban boundary layer, both in terms of concentration and composition. As many of the atmospheric chemical process are non-linear and interlinked, this makes predictions difficult for species formed in atmosphere, such as ozone, requiring field measurements to understand these processes in order to guide mitigation efforts. To investigate the ozone formation potential of ambient air, we employed a custom built instrument to measure in near real time the potential for in situ ozone production, using an artificial light source. Our results are thus indicative of the ozone formation potential for the sampled ambient air mixture. Measurements were performed as part of the Air Pollution and Human Health (APHH) field campaign in November / December 2016 at a suburban site in central Beijing. We also conducted experiments to examine the ozone production sensitivity to NOx. We will present preliminarily results from ambient sampling and NOx experiments demonstrating changes in the ozone production potential during clean and haze periods in Beijing.

  20. Waste rice seed in conventional and stripper-head harvested fields in California: Implications for wintering waterfowl

    Science.gov (United States)

    Fleskes, Joseph P.; Halstead, Brian J.; Casazza, Michael L.; Coates, Peter S.; Kohl, Jeffrey D.; Skalos, Daniel A.

    2012-01-01

    Waste rice seed is an important food for wintering waterfowl and current estimates of its availability are needed to determine the carrying capacity of rice fields and guide habitat conservation. We used a line-intercept method to estimate mass-density of rice seed remaining after harvest during 2010 in the Sacramento Valley (SACV) of California and compared results with estimates from previous studies in the SACV and Mississippi Alluvial Valley (MAV). Posterior mean (95% credible interval) estimates of total waste rice seed mass-density for the SACV in 2010 were 388 (336–449) kg/ha in conventionally harvested fields and 245 (198–307) kg/ha in stripper-head harvested fields; the 2010 mass-density is nearly identical to the mid-1980s estimate for conventionally harvested fields but 36% lower than the mid-1990s estimate for stripped fields. About 18% of SACV fields were stripper-head harvested in 2010 vs. 9–15% in the mid-1990s and 0% in the mid-1980s; but due to a 50% increase in planted rice area, total mass of waste rice seed in SACV remaining after harvest in 2010 was 43% greater than in the mid-1980s. However, total mass of seed-eating waterfowl also increased 82%, and the ratio of waste rice seed to seed-eating waterfowl mass was 21% smaller in 2010 than in the mid-1980s. Mass-densities of waste rice remaining after harvest in SACV fields are within the range reported for MAV fields. However, because there is a lag between harvest and waterfowl use in the MAV but not in the SACV, seed loss is greater in the MAV and estimated waste seed mass-density available to wintering waterfowl in SACV fields is about 5–30 times recent MAV estimates. Waste rice seed remains an abundant food source for waterfowl wintering in the SACV, but increased use of stripper-head harvesters would reduce this food. To provide accurate data on carrying capacities of rice fields necessary for conservation planning, trends in planted rice area, harvest method, and postharvest field

  1. The Polar BEAR magnetic field experiment

    Science.gov (United States)

    Bythrow, P. F.; Potemra, T. A.; Zanetti, L. J.; Mobley, F. F.; Scheer, L.; Radford, W. E.

    1987-09-01

    The objectives and the instrumentation of the Polar BEAR magnetic field experiment are described along with the preliminary results from simultaneous measurements of Birkeland currents and UV auroral emissions. The experiment consists of an integrated sensor head, analog electronics, and digital electronics. The sensor head is a single unit containing sensor windings for each of the three orthogonal axes, oriented parrallel to the spacecraft coordinates; to minimize interference from spacecraft-generated magnetic fields, the sensor unit is located at the end of the +y solar panel. The digital electronics package is essentially identical to that flown on HILAT. A signal processor digitizes the analog outputs of the three orthogonal axes of the flux-gate magnetometer to a 13-bit resolution, yielding a magnetic field range of + or - 63,000 nT and a resolution of 15.2 nT. The full-resolution magnetic field values are recovered by data processing techniques on the ground.

  2. A Field Experiment in Motivating Employee Ideas

    OpenAIRE

    Susanne Neckermann; Michael Gibbs; Christoph Siemroth

    2014-01-01

    markdownabstract__Abstract__ We study the effects of a field experiment designed to motivate employee ideas, at a large technology company. Employees were encouraged to submit ideas on process and product improvements via an online system. In the experiment, the company randomized 19 account teams into treatment and control groups. Employees in treatment teams received rewards if their ideas were approved. Nothing changed for employees in control teams. Our main finding is that rewards substa...

  3. (Notes) On Experience in the Field

    DEFF Research Database (Denmark)

    Beloff, Laura

    2013-01-01

    that there would not be experience within science but it is typically not the primary result aimed at within the (e.g. natural) sciences. The article deliberately avoids making any precise definitions for artistic practices that relate to science research to evade fixed perception of the field that is evolving...

  4. Employee Recognition and Performance: A Field Experiment

    NARCIS (Netherlands)

    C. Bradler (Christiane); A.J. Dur (Robert); S. Neckermann (Susanne); J.A. Non (Arjan)

    2013-01-01

    textabstractThis paper reports the results from a controlled field experiment designed to investigate the causal effect of public recognition on employee performance. We hired more than 300 employees to work on a three-hour data-entry task. In a random sample of work groups, workers unexpectedly

  5. Winter Wheat Root Growth and Nitrogen Relations

    DEFF Research Database (Denmark)

    Rasmussen, Irene Skovby

    in winter wheat (Triticum aestivum L). Field experiments on the effect of sowing date, N fertilization and cultivars were conducted on a sandy loam soil in Taastrup, Denmark. The root studies were conducted by means of the minirhizotron method. Also, a field experiment on the effect of defoliation and N...

  6. Rainfall Process Partitioning Using S-PROF Radar Observations Collected During the CalWater Field Campaign Winters

    Science.gov (United States)

    White, A. B.; Neiman, P. J.; Creamean, J.; Hughes, M. R.; Moore, B.; Ralph, F. M.; Prather, K. A.

    2011-12-01

    Vertically pointing S-band radar (S-PROF) observations collected during the CalWater field campaign winter wet seasons are analyzed to partition the observed rainfall into three primary categories: brightband (BB) rain, non-brightband (NBB) rain, and convective rain. NBB rain is primarily a shallow, warm rain process driven by collision and coalescence. Because of its shallow nature, NBB rain is often undetected by the operational NEXRAD radar network. Previous rainfall process partitioning analysis conducted for a coastal mountain site in California has shown that NBB rain contributes about one-third, on average, of the total wet season precipitation observed there. Shallow moist flow with near neutral stability, which is often present in the coastal environment during the warm sectors of landfalling storms, is a key ingredient in the formation of NBB rain. However, NBB rain also has been observed in other storm regimes (e.g., post-cold frontal). NBB rain has been shown to produce rain rates known by forecasters to be capable of producing floods. During the CalWater field campaign winters, S-PROF radars were located in the Sierra Nevada at Sugar Pine Dam (SPD) for three consecutive winters (2009-2011) and at Mariposa (MPI) for the latter two winters (2010-2011). During the southwesterly flow present in the warm sectors of many California landfalling storms, the SPD site was directly downwind of the gap in coastal terrain associated with the San Francisco Bay Delta. This orientation would allow relatively unmodified maritime flow to arrive at SPD. The MPI site was located further south such that airflow arriving at this site during winter storms likely was processed by the coastal terrain south of San Francisco Bay. In this presentation we will examine whether the relative locations of SPD and MPI relative to the coastal terrain impacted the amount of NBB rain that was observed at each site during the CalWater wet seasons. We will use synoptic and mesoscale

  7. Hibernating black bears (Ursus americanus) experience skeletal muscle protein balance during winter anorexia.

    Science.gov (United States)

    Lohuis, T D; Harlow, H J; Beck, T D I

    2007-05-01

    Black bears spend four to seven months every winter confined to their den and anorexic. Despite potential for skeletal muscle atrophy and protein loss, bears appear to retain muscle integrity throughout winter dormancy. Other authors have suggested that bears are capable of net protein anabolism during this time. The present study was performed to test this hypothesis by directly measuring skeletal muscle protein metabolism during the summer, as well as early and late hibernation periods. Muscle biopsies were taken from the vastus lateralis of six free-ranging bears in the summer, and from six others early in hibernation and again in late winter. Protein synthesis and breakdown were measured on biopsies using (14)C-phenylalanine as a tracer. Muscle protein, nitrogen, and nucleic acid content, as well as nitrogen stable isotope enrichment, were also measured. Protein synthesis was greater than breakdown in summer bears, suggesting that they accumulate muscle protein during periods of seasonal food availability. Protein synthesis and breakdown were both lower in winter compared to summer but were equal during both early and late denning, indicating that bears are in protein balance during hibernation. Protein and nitrogen content, nucleic acid, and stable isotope enrichment measurements of the biopsies support this conclusion.

  8. Utilizing Urban Environments for Effective Field Experiences

    Science.gov (United States)

    MacAvoy, S. E.; Knee, K.

    2014-12-01

    Research surveys suggest that students are demanding more applied field experiences from their undergraduate environmental science programs. For geoscience educators at liberal arts colleges without field camps, university vehicles, or even geology departments, getting students into the field is especially rewarding - and especially challenging. Here, we present strategies that we have used in courses ranging from introductory environmental science for non-majors, to upper level environmental methods and geology classes. Urban locations provide an opportunity for a different type of local "field-work" than would otherwise be available. In the upper-level undergraduate Environmental Methods class, we relied on a National Park area located a 10-minute walk from campus for most field exercises. Activities included soil analysis, measuring stream flow and water quality parameters, dendrochronology, and aquatic microbe metabolism. In the non-majors class, we make use of our urban location to contrast water quality in parks and highly channelized urban streams. Here we share detailed lesson plans and budgets for field activities that can be completed during a class period of 2.5 hours with a $75 course fee, show how these activities help students gain quantitative competency, and provide student feedback about the classes and activities.

  9. FRONT COMMANDS IN WINTER OF 1917 IN COMBATING CRISIS OF FOOD SUPPLY TO FIELD FORCES

    Directory of Open Access Journals (Sweden)

    Максим Викторович Оськин

    2015-12-01

    Full Text Available This article considers the problem of food supply to the Eastern front in the winter of 1917 during World War I. In the conditions of the food supply crisis the military authorities managed to avoid the famine in the army. The Front Command and the Supreme Command took some measures to resolve this problem. Attracting extra workers for harvesting, clarity of the resources allocation, calculations of the government funds allocation- all these actions bolstered the army's efforts on the home front. A considerable role in this work was played by Emperor Nicholas II, who timely and positively reacted to the suggestions of the military commanders on the issue. Overall, the Russian military command coped with this problem in the conditions of the general crisis of supplies.

  10. An experimental field evaluation of winter carryover effects in semi-anadromous Brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Midwood, Jonathan D.; Larsen, Martin Hage; Boel, Mikkel

    2015-01-01

    For semi-anadromous brown trout, the decision whether or not to smoltify and migrate to the sea is believed to be made at the end of the preceding summer in response to both local environmental conditions and individual physiological status. Stressors experienced during the fall may therefore...... influence their propensity to migrate as well as carry over into the winter resulting in mortality when fish face challenging environmental conditions. To evaluate this possibility, we artificially elevated cortisol levels in juvenile trout (via intracoelomic injection of cortisol in the fall) and used...... passive integrated transponder tags to compare their overwinter and spring survival, growth, and migration success relative to a control group. Results suggest that overwinter mortality is high for individuals in this population regardless of treatment. However, survival rates were 2.5 times lower...

  11. The FIELDS experiment for Solar Probe Plus

    Science.gov (United States)

    Bale, S.; Spp/Fields Team

    2010-12-01

    Many of our basic ideas on the plasma physics of acceleration, energy flow, and dissipation, and structure of the solar wind have never been rigorously confronted by direct experimental measurements in the region where these processes are actually occurring. Although Alfven waves, shocks, and magnetic reconnection are often invoked as heating mechanisms, there have never been any direct measurements of Alfvenic waves nor the associated Poynting flux nor any measurements of ion or electron kinetic energy flux in the region from 10 R_s to 30 R_s where the final stages of wind acceleration are believed to occur. The radial profiles of both slow and fast solar wind acceleration are based on remote-sensing measurements and have been obtained for only a few selected events. Thus, the spatial radial and perpendicular scales of the acceleration process have been averaged by line-of-sight effects and the possibility of intense localized acceleration cannot be ruled out. The Solar Probe Plus (SPP) mission calls for the high quality fields and particles measurements required to solve the coronal heating and wind acceleration problem. The SPP 'FIELDS' experiment measures the electric and magnetic fields fundamental to the plasma physics of the structured and turbulent solar wind, flux ropes, collisionless shocks, and magnetic reconnection. FIELDS will make the first-ever measurements of the DC/Low-Frequency electric field inside of 1 AU allowing for in situ, high cadence measurements of the Poynting vector, the Elsasser variables, and E/B diagnostics of the wave spectrum to fce in the solar wind. SPP/FIELDS measures the radio wave (type III and II) signatures of microflares, energized electrons, and CME propagation. SPP/ FIELDS measures the plasma electron density to ~2% accuracy and the core electron temperature to ~5-10% accuracy more than 90% of the time at perihelion. FIELDS will also measure the in situ density fluctuation spectrum and structures at a very high cadence (

  12. Elusive Neutrinos : the picture shows Klaus Winter, who worked on the 100 tonne CHARM experiment.

    CERN Multimedia

    1978-01-01

    Catching neutrinos isn't easy. They interact only rarely with matter, so they have a good chance of passing straight through the Earth without stopping. However, when they do interact it is possible to see what effect they have on other particles. CERN had been doing this type of research for more than a decade by the time the detector was finished in 1977. CHARM is seen here in the West Area where it was set up with the 1250 tonne CDHS experiment. Researchers used these machines to help develop the Standard Model of particle physics and further our understanding of the structure of the atomic nucleus. The research also helped expand physics into a new field aimed at understanding the peculiar behaviour of neutrinos. There are three 'flavours' of neutrino - the electron, muon, and the tau neutrino. Over a long enough distance, they oscillate from one flavour to another.

  13. Multiproxy summer and winter surface air temperature field reconstructions for southern South America covering the past centuries

    Energy Technology Data Exchange (ETDEWEB)

    Neukom, R.; Grosjean, M.; Wanner, H. [University of Bern, Oeschger Centre for Climate Change Research (OCCR), Bern (Switzerland); University of Bern, Institute of Geography, Climatology and Meteorology, Bern (Switzerland); Luterbacher, J. [Justus Liebig University of Giessen, Department of Geography, Climatology, Climate Dynamics and Climate Change, Giessen (Germany); Villalba, R.; Morales, M.; Srur, A. [CONICET, Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales (IANIGLA), Mendoza (Argentina); Kuettel, M. [University of Bern, Oeschger Centre for Climate Change Research (OCCR), Bern (Switzerland); University of Bern, Institute of Geography, Climatology and Meteorology, Bern (Switzerland); University of Washington, Department of Earth and Space Sciences, Seattle (United States); Frank, D. [Swiss Federal Research Institute WSL, Birmensdorf (Switzerland); Jones, P.D. [University of East Anglia, Climatic Research Unit, School of Environmental Sciences, Norwich (United Kingdom); Aravena, J.-C. [Centro de Estudios Cuaternarios de Fuego Patagonia y Antartica (CEQUA), Punta Arenas (Chile); Black, D.E. [Stony Brook University, School of Marine and Atmospheric Sciences, Stony Brook (United States); Christie, D.A.; Urrutia, R. [Universidad Austral de Chile Valdivia, Laboratorio de Dendrocronologia, Facultad de Ciencias Forestales y Recursos Naturales, Valdivia (Chile); D' Arrigo, R. [Earth Institute at Columbia University, Tree-Ring Laboratory, Lamont-Doherty Earth Observatory, Palisades, NY (United States); Lara, A. [Universidad Austral de Chile Valdivia, Laboratorio de Dendrocronologia, Facultad de Ciencias Forestales y Recursos Naturales, Valdivia (Chile); Nucleo Cientifico Milenio FORECOS, Fundacion FORECOS, Valdivia (Chile); Soliz-Gamboa, C. [Utrecht Univ., Inst. of Environmental Biology, Utrecht (Netherlands); Gunten, L. von [Univ. of Bern (Switzerland); Univ. of Massachusetts, Climate System Research Center, Amherst (United States)

    2011-07-15

    We statistically reconstruct austral summer (winter) surface air temperature fields back to ad 900 (1706) using 22 (20) annually resolved predictors from natural and human archives from southern South America (SSA). This represents the first regional-scale climate field reconstruction for parts of the Southern Hemisphere at this high temporal resolution. We apply three different reconstruction techniques: multivariate principal component regression, composite plus scaling, and regularized expectation maximization. There is generally good agreement between the results of the three methods on interannual and decadal timescales. The field reconstructions allow us to describe differences and similarities in the temperature evolution of different sub-regions of SSA. The reconstructed SSA mean summer temperatures between 900 and 1350 are mostly above the 1901-1995 climatology. After 1350, we reconstruct a sharp transition to colder conditions, which last until approximately 1700. The summers in the eighteenth century are relatively warm with a subsequent cold relapse peaking around 1850. In the twentieth century, summer temperatures reach conditions similar to earlier warm periods. The winter temperatures in the eighteenth and nineteenth centuries were mostly below the twentieth century average. The uncertainties of our reconstructions are generally largest in the eastern lowlands of SSA, where the coverage with proxy data is poorest. Verifications with independent summer temperature proxies and instrumental measurements suggest that the interannual and multi-decadal variations of SSA temperatures are well captured by our reconstructions. This new dataset can be used for data/model comparison and data assimilation as well as for detection and attribution studies at sub-continental scales. (orig.)

  14. The Emissions of Carbon Dioxide, Methane, and Nitrous Oxide during Winter without Cultivation in Local Saline-Alkali Rice and Maize Fields in Northeast China

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2017-10-01

    Full Text Available Agricultural ecosystems are important contributors to atmospheric greenhouse gasses (GHGs; however, in situ winter emission data in saline-alkali fields are scarce. Gas samples were collected during different periods, from three rice (R1–R3 and three maize (M1–M3 fields with different soil pH levels and salinity conditions. Carbon dioxide (CO2 emissions in the rice and maize fields decreased with decreasing temperature during the freezing period and increased with the rising temperature during the thawing period, with the majority of winter CO2 emissions occurring during these two periods. Peaks in methane (CH4 emissions were observed during the freezing period in the rice fields and during the snow-melting period in the rice and maize fields. CH4 emissions in the rice fields and CH4 uptake rates in the maize fields were significantly (P < 0.05 related to surface soil temperature. Nitrous oxide (N2O emissions remained relatively low, except for during the peaks observed during the snow-melting period in both the rice and maize fields, leading to the high GHG contribution of the snow-melting period throughout the winter. Higher pH and salinity conditions consistently resulted in lower CO2, CH4, and N2O emissions, CH4 uptake, and lower global warming potential (GWP. These results can contribute to the assessment of the GWP during winter in saline-alkali regions.

  15. [Effects of mulching on soil moisture in a dryland winter wheat field, Northwest China].

    Science.gov (United States)

    Fan, Ying-Dan; Chai, Shou-Xi; Cheng, Hong-Bo; Chen, Yu-Zhang; Yang, Chang-Gang; Huang, Cai-Xia; Chang, Lei; Pang, Lei

    2013-11-01

    This paper studied the effects of different mulching modes on the soil moisture in a semi-arid rainfed area of Loess Plateau, Northwest China. Seven treatments were installed, i. e., mulching plastic film in summer (T1), mulching plastic film in autumn (T2), mulching 5 cm long wheat straw in summer (T3), mulching whole wheat straw in summer (T4), mulching plastic film in summer plus wheat straw (T5), mulching used plastic film after harvest (T6), and un-mulching (CK). In T6, the soil moisture in different layers at different crop growth stages was all higher than that in CK. In the other five mulching treatments, the soil moisture in 0-90 cm layer before flowering stage was obviously higher, but that in 0-90 cm layer after flowering stage and in 90-200 cm layer during the whole growth season was lower than that of CK. The soil moisture in 0-200 cm layer in T6 during the whole growth period was significantly higher than that in CK, with a difference of 0.9%, but the soil moisture in 0-200 cm layer in other mulching treatments was lower. As compared with plastic film mulching, straw mulching increased the soil moisture in 0-200 cm layer. The soil moisture under mulching with used plastic film after harvest was higher than that under mulching with new plastic film. As compared to CK, the grain yield of winter wheat with plastic film mulching was increased by 20.3%-29.0%, and that With straw mulching was increased by 5.0%-16.7%. There was a significant positive correlation between the crop productivity and the soil water consumption during the growth period (r = 0.77*).

  16. A Field Study on the Indoor Thermal Environment of the Airport Terminal in Tibet Plateau in Winter

    Directory of Open Access Journals (Sweden)

    Jianglong Zhen

    2017-01-01

    Full Text Available In order to study the characteristics of indoor thermal environment in the airport terminal in Tibet Plateau with radiant floor heating in winter, a field measurement of the indoor thermal environment was conducted in Lhasa Gonggar Airport terminal 2. First, the unique climate characteristics in Tibet Plateau were analyzed through comparison of meteorological parameters in Beijing and Lahsa. The thermal environment in the terminal was divided into outer zone and inner zone as well as south zone and north zone. Thermal environment parameters including air temperature, black globe temperature, relative humidity in each zone, and inner surface temperature of envelope were measured and analyzed. Meanwhile, temperature and relative humidity in the vertical direction were measured. In addition, PMV and PPD were calculated for evaluating the thermal environment in the terminal. The findings can provide guidance for the design and regulation of thermal environment in terminals in Tibet Plateau in China.

  17. Winter Texans and the re-creation of the American medical experience in Mexico.

    Science.gov (United States)

    Dalstrom, Matthew D

    2012-01-01

    Rising medical costs and decreasing health insurance coverage are fueling the health care crisis in the United States. Often, patients have to make tough decisions about whether to forgo care or risk bankruptcy. This conundrum has encouraged some patients to use Mexican health care as an alternative to the high costs in the United States. While medical travel enables some patients to access affordable care, others perceive it as risky and thus not a viable option. This article explores how those concerns are mitigated and Mexican health care usage is increased by (1) outlining how Mexican health care information is disseminated and used within a community of winter Texans living along the US/Mexico border; and (2) discussing how Mexican pharmacies and dental clinics have broadened their appeal through association with US health care standards and practices. Research for this article was conducted during 11 months of fieldwork in the Lower Rio Grande Valley.

  18. Lectures from the European RTN Winter School on Strings, Supergravity and Gauge Fields, CERN, 15 19 January 2007

    Science.gov (United States)

    Derendinger, J.-P.; Scrucca, C. A.; Uranga, A.

    2007-11-01

    This special issue is devoted to the proceedings of the conference 'Winter School on Strings, Supergravity and Gauge Theories', which took place at CERN, the European Centre for Nuclear Research, in Geneva, Switzerland, from the 15 to the 19 of January 2007. This event was organized in the framework of the European Mobility Research and Training Network entitled 'Constituents, Fundamental Forces and Symmetries of the Universe'. It is part of a yearly series of scientific schools, which represents what is by now a well established tradition. The previous conferences have been held at SISSA, in Trieste, Italy, in February 2005 and at CERN in January 2006. The next will again take place at CERN, in January 2008. The school was primarily meant for young doctoral students and postdoctoral researchers working in the area of string theory. It consisted of several general lectures of four hours each, the notes of which are published in the present proceedings, and seven working group discussion sessions, focused on specific topics of the network research program. It was attended by approximatively 250 participants. The topics of the lectures were chosen to provide an introduction to some of the areas of recent progress, and to the open problems, in string theory. String theory is a compelling candidate for a theory of all interactions. A basic challenge in this field is therefore to explore the connection of string theory models and the laws of physics in different realms, like high-energy particle physics, early cosmology, or physics of strongly coupled gauge theories. Concerning the exploration of string theory compactifications leading to realistic models of particle physics, one of the main obstacles in this direction is the proper understanding of supersymmetry breaking. The lecture notes by Nathan Seiberg review the realization of spontaneous breaking of supersymmetry in field theory, including recent developments via the use of meta-stable long-lived vacua. It is

  19. Turbulence influence on urban air pollution in a hot spot in Madrid: comparison of winter and summer field campaigns

    Science.gov (United States)

    Yagüe, Carlos; Román-Cascón, Carlos; Sastre, Mariano; Maqueda, Gregorio; Arrillaga, Jon A.; Artiñano, Begoña; Díaz-Ramiro, Elías; Gómez-Moreno, Francisco J.; Borge, Rafael; Narros, Adolfo; Pérez, Javier; Quaassdorff, Christina

    2017-04-01

    Air pollution is a major problem in the city of Madrid during weak synoptic forcing, since the presence of atmospheric stability conditions often develops night surface-based thermal inversions and subsidence inversions during daytime for several consecutive days, reaching high levels of NOx and Particulate Matter (PM) concentration. In this context, the TECNAIRE-CM (Innovative technologies for the assessment and improvement of urban air quality) research project has developed two field campaigns along 2015 (winter and summer) in a hot spot in the city of Madrid (Fernández Ladreda square). This hot spot includes one important intersection of different streets and also the start of the A42 motorway, which crosses down the square through a tunnel of about 150 m length. Besides, the location has numerous traffic lights and a lot of pedestrians walking in the vicinity. In addition to direct measurements related to air quality, data from different meteorological variables were recorded in order to characterize the atmospheric conditions. Moreover, two sonic anemometers where deployed to carry out a micrometeorological assessment of physical processes that take place in the urban atmospheric surface layer (TKE, friction velocity and sensible heat flux were evaluated). The evolution of the turbulence will be analyzed and compared for both campaigns (winter and summer), searching for the key seasonal differences as well as the importance of the different scales influencing the diffusion of pollutants (from multi resolution flux decomposition -MRFD- analysis). Specific case studies corresponding to high levels of pollution will be studied in detailed, to understand local pollution dynamics under the influence of both high traffic density and low turbulence situations. This work has been financed by Madrid Regional Research Plan through TECNAIRE (P2013/MAE-2972).

  20. Field Education in Debate: experiences of fight!

    Directory of Open Access Journals (Sweden)

    Rafael Rossi

    2015-08-01

    Full Text Available In this paper approached the question the field education as a potentiality for greater participation of the families of students in the organization and daily life of schools in rural settlements. In many cases, urban educational standards are reproduced uncritically on peasant territory. Thus, the school becomes an alienated and alienating element before its spatial context and struggle of the settlements. The work is based in the investigative experience in Paulo Freire’ Educator School, located in the settlement Rodeo in the Presidente Bernardes City, in São Paulo State. To discuss the need for dialogue as forums on the field education and collective meetings with the school community, so that the school is effectively that peasant population, built and organized according to the demands of this location and territory. In this sense, communication and the construction of channels that care about dialogue so that the community can express themselves and be able to attend the school, are fundamental issues to be discussed at a prerogative which is based on democratic posture of the school.

  1. Simulation of the Impacts of Urbanization on Winter Meteorological Fields over the Pearl River Delta Region

    Directory of Open Access Journals (Sweden)

    Naixing Luo

    2017-01-01

    Full Text Available The influences of urbanization on weather in Guangdong Province, China, were studied using the Weather Research and Forecasting model from 31 December 2009 through 3 January 2010. Model outputs were compared with extensive monitoring of meteorological data to examine the simulation ability. Model results between tests (with and without land-use change show that the urbanization had major effects on meteorological fields across nearly the entire Pearl River Delta region and particularly in urban areas. Studied fields (wind speed, temperature, precipitation, and sensible and latent heat fluxes were affected by the urbanization of the PRD region. The major influences occurred in urban areas, where wind speeds decreased greatly, while the daytime surface upward sensible heat flux clearly increased. Unlike the sensible heat flux, the latent heat flux had a nonmonotonic increase or decrease. As a consequence of the two heat fluxes, 2-m temperature varied with location and time. Change of precipitation was complex. The main rain band became more concentrated, while precipitation decreased upwind of the urban area and increased downwind.

  2. Large-scale pollination experiment demonstrates the importance of insect pollination in winter oilseed rape.

    Science.gov (United States)

    Lindström, Sandra A M; Herbertsson, Lina; Rundlöf, Maj; Smith, Henrik G; Bommarco, Riccardo

    2016-03-01

    Insect pollination, despite its potential to contribute substantially to crop production, is not an integrated part of agronomic planning. A major reason for this are knowledge gaps in the contribution of pollinators to yield, which partly result from difficulties in determining area-based estimates of yield effects from insect pollination under field conditions. We have experimentally manipulated honey bee Apis mellifera densities at 43 oilseed rape Brassica napus fields over 2 years in Scandinavia. Honey bee hives were placed in 22 fields; an additional 21 fields without large apiaries in the surrounding landscape were selected as controls. Depending on the pollination system in the parental generation, the B. napus cultivars in the crop fields are classified as either open-pollinated or first-generation hybrids, with both types being open-pollinated in the generation of plants cultivated in the fields. Three cultivars of each type were grown. We measured the activity of flower-visiting insects during flowering and estimated yields by harvesting with small combine harvesters. The addition of honey bee hives to the fields dramatically increased abundance of flower-visiting honey bees in those fields. Honey bees affected yield, but the effect depended on cultivar type (p = 0.04). Post-hoc analysis revealed that open-pollinated cultivars, but not hybrid cultivars, had 11% higher yields in fields with added honey bees than those grown in the control fields (p = 0.07). To our knowledge, this is the first whole-field study in replicated landscapes to assess the benefit of insect pollination in oilseed rape. Our results demonstrate that honey bees have the potential to increase oilseed rape yields, thereby emphasizing the importance of pollinator management for optimal cultivation of oilseed rape.

  3. Manipulating field margins to increase predation intensity in fields of winter wheat (Triticum eastivum)

    DEFF Research Database (Denmark)

    Mansion-Vaquie, Agathe; Ferrante, Marco; Cook, S M

    2017-01-01

    to the two margin types: specialists (mostly parasitic wasps) were attracted by the flower margins, while generalists (ground beetles, rove beetles and spiders) were more active in grass margins. The number of artificial caterpillars attacked was significantly greater in grass margins (mean = 48.9%, SD = 24.......3) than in flower margins (mean = 30.7%, SD = 17.4). We found a significant positive relationship between the number of artificial caterpillars attacked by chewing insects, and activity density for large (≥15 mm) ground beetles. Predation of sentinel aphids in wheat fields did not vary significantly...

  4. 1. Introduction. 2. Laboratory experiments. 3. Field experiments. 4. Integrated field-laboratory experiments. 5. Panel recommendations

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Some recommendations for the design of laboratory and field studies in marine radioecology are formulated. The difficulties concerning the comparability of various experimental methods used to measure the fluxes of radionuclides through marine organisms and ecosystems, and also the use of laboratory results to make predictions for the natural environment are discussed. Three working groups were established during the panel meeting, to consider laboratory experiments, field studies, and the design and execution of integrated laboratory and field studies respectively. A number of supporting papers dealing with marine radioecological experiments were presented

  5. An Experiment with Air Purifiers in Delhi during Winter 2015-2016.

    Science.gov (United States)

    Vyas, Sangita; Srivastav, Nikhil; Spears, Dean

    2016-01-01

    Particulate pollution has important consequences for human health, and is an issue of global concern. Outdoor air pollution has become a cause for alarm in India in particular because recent data suggest that ambient pollution levels in Indian cities are some of the highest in the world. We study the number of particles between 0.5μm and 2.5μm indoors while using affordable air purifiers in the highly polluted city of Delhi. Though substantial reductions in indoor number concentrations are observed during air purifier use, indoor air quality while using an air purifier is frequently worse than in cities with moderate pollution, and often worse than levels observed even in polluted cities. When outdoor pollution levels are higher, on average, indoor pollution levels while using an air purifier are also higher. Moreover, the ratio of indoor air quality during air purifier use to two comparison measures of air quality without an air purifier are also positively correlated with outdoor pollution levels, suggesting that as ambient air quality worsens there are diminishing returns to improvements in indoor air quality during air purifier use. The findings of this study indicate that although the most affordable air purifiers currently available are associated with significant improvements in the indoor environment, they are not a replacement for public action in regions like Delhi. Although private solutions may serve as a stopgap, reducing ambient air pollution must be a public health and policy priority in any region where air pollution is as high as Delhi's during the winter.

  6. Winter Weather

    Science.gov (United States)

    ... Education Centers Harwood Training Grants Videos E-Tools Winter Storms Plan. Equip. Train To prevent injuries, illnesses and Fatalities during winter storms. This page requires that javascript be enabled ...

  7. Habit versus planned behaviour: a field experiment.

    Science.gov (United States)

    Verplanken, B; Aarts, H; van Knippenberg, A; Moonen, A

    1998-03-01

    A field experiment investigated the prediction and change in repeated behaviour in the domain of travel mode choices. Car use during seven days was predicted from habit strength (measured by self-reported frequency of past behaviour, as well as by a more covert measure based on personal scripts incorporating the behaviour), and antecedents of behaviour as conceptualized in the theory of planned behaviour (attitude, subjective norm, perceived behavioural control and behavioural intention). Both habit measures predicted behaviour in addition to intention and perceived control. Significant habit x intention interactions indicated that intentions were only significantly related to behaviour when habit was weak, whereas no intention-behaviour relation existed when habit was strong. During the seven-day registration of behaviour, half of the respondents were asked to think about the circumstances under which the behaviour was executed. Compared to control participants, the behaviour of experimental participants was more strongly related to their previously expressed intentions. However, the habit-behaviour relation was unaffected. The results demonstrate that, although external incentives may increase the enactment of intentions, habits set boundary conditions for the applicability of the theory of planned behaviour.

  8. Winter MVC

    OpenAIRE

    Castellón Gadea, Pasqual

    2013-01-01

    Winter MVC és un framework de presentació basat en Spring MVC que simplifica la metodologia de configuracions. Winter MVC es un framework de presentación basado en Spring MVC que simplifica la metodología de configuraciones. Winter MVC is a presentation framework that simplifies Spring MVC configuration methodology.

  9. Contribution of allelopathy and competition to weed suppression by winter wheat, triticale and winter rye

    DEFF Research Database (Denmark)

    Reiss, Antje; Fomsgaard, Inge S.; Mathiassen, Solvejg Kopp

    of competitive traits, such as early vigour, crop height and leaf area index and presence of phytotoxic compounds of the group of benzoxazinoids to weed suppression. Four cultivars of each of the winter cereals wheat, triticale and rye were grown in field experiments at two locations. Soil samples were taken...... 2016. Competitive traits were measured throughout the growing season. Partial least squares regression with weed biomass as response variable was used for modelling. Competitive traits, as well as benzoxazinoid concentrations contributed significantly to the models on winter wheat, winter triticale...... and winter rye data and explained 63, 69 and 58% of the variance in weed biomass in the first two components, respectively. Consequently, it can be concluded that competitive, as well as allelopathic traits, contributed significantly to weed suppressive outcome in winter cereals. This knowledge...

  10. Field investigations of apparent optical properties of ice cover in Finnish and Estonian lakes in winter 2009

    Directory of Open Access Journals (Sweden)

    Ruibo Lei

    2011-03-01

    Full Text Available A field programme on light conditions in ice-covered lakes and optical properties of lake ice was performed in seven lakes of Finland and Estonia in February–April 2009. On the basis of irradiance measurements above and below ice, spectral reflectance and transmittance were determined for the ice sheet; time evolution of photosynthetically active radiation (PAR transmittance was examined from irradiance recordings at several levels inside the ice sheet. Snow cover was the dominant factor for transmission of PAR into the lake water body. Reflectance was 0.74–0.92 in winter, going down to 0.18–0.22 in the melting season. The bulk attenuation coefficient of dry snow was 14–25 m–1; the level decreased as the spring was coming. The reflectance and bulk attenuation coefficient of snow-free ice were 0.1–0.4 and 1–5 m–1. Both were considerably smaller than those of snow cover. Seasonal evolution of light transmission was mainly due to snow melting. Snow and ice cover not only depress the PAR level in a lake but also influence the spectral and directional distribution of light.

  11. A draft genome of field pennycress (Thlaspi arvense) provides tools for the domestication of a new winter biofuel crop.

    Science.gov (United States)

    Dorn, Kevin M; Fankhauser, Johnathon D; Wyse, Donald L; Marks, M David

    2015-04-01

    Field pennycress (Thlaspi arvense L.) is being domesticated as a new winter cover crop and biofuel species for the Midwestern United States that can be double-cropped between corn and soybeans. A genome sequence will enable the use of new technologies to make improvements in pennycress. To generate a draft genome, a hybrid sequencing approach was used to generate 47 Gb of DNA sequencing reads from both the Illumina and PacBio platforms. These reads were used to assemble 6,768 genomic scaffolds. The draft genome was annotated using the MAKER pipeline, which identified 27,390 predicted protein-coding genes, with almost all of these predicted peptides having significant sequence similarity to Arabidopsis proteins. A comprehensive analysis of pennycress gene homologues involved in glucosinolate biosynthesis, metabolism, and transport pathways revealed high sequence conservation compared with other Brassicaceae species, and helps validate the assembly of the pennycress gene space in this draft genome. Additional comparative genomic analyses indicate that the knowledge gained from years of basic Brassicaceae research will serve as a powerful tool for identifying gene targets whose manipulation can be predicted to result in improvements for pennycress. © The Author 2015. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  12. Herbicide impact on the growth and reproduction of characteristic and rare arable weeds of winter cereal fields.

    Science.gov (United States)

    Rotchés-Ribalta, Roser; Boutin, Céline; Blanco-Moreno, José M; Carpenter, David; Sans, F Xavier

    2015-07-01

    The decline of arable species characteristic of winter cereal fields has often been attributed to different factors related to agricultural intensification but most importantly to herbicide use. Herbicide phytotoxicity is most frequently assessed using short-term endpoints, primarily aboveground biomass. However, short-term sensitivity is usually not sufficient to detect actual effects because plants may or may not recover over time following sublethal herbicide exposures. Therefore, it is important to assess the long-term effects of herbicide applications. Annual species rely on renewable seed production to ensure their persistence; hence, assessment of herbicide sensitivity is more accurately estimated through effects on reproduction. Here we aim to assess the phytotoxicity of two commonly used herbicides: tribenuron and 2,4-D on eight plant species belonging to four families, each with one rare and one more common species. Specifically we examined the pattern of sensitivity using short-term and long-term endpoints (total aboveground biomass, total seed biomass and number of seeds) of these species; we determined the levels of and time to recovery in terms of stem length and fruit number, and assessed whether their rarity relates to their sensitivity to herbicide application. Our results suggest that although differences in herbicide sensitivity are not a direct cause of rarity for all species, it may be an important driver of declining arable plants.

  13. Global observations of electromagnetic and particle energy flux for an event during northern winter with southward interplanetary magnetic field

    Directory of Open Access Journals (Sweden)

    H. Korth

    2008-06-01

    Full Text Available The response of the polar ionosphere–thermosphere (I-T system to electromagnetic (EM energy input is fundamentally different to that from particle precipitation. To understand the I-T response to polar energy input one must know the intensities and spatial distributions of both EM and precipitation energy deposition. Moreover, since individual events typically display behavior different from statistical models, it is important to observe the global system state for specific events. We present an analysis of an event in Northern Hemisphere winter for sustained southward interplanetary magnetic field (IMF, 10 January 2002, 10:00–12:00 UT, for which excellent observations are available from the constellation of Iridium satellites, the SuperDARN radar network, and the Far-Ultraviolet (FUV instrument on the IMAGE satellite. Using data from these assets we determine the EM and particle precipitation energy fluxes to the Northern Hemisphere poleward of 60° MLAT and examine their spatial distributions and intensities. The accuracy of the global estimates are assessed quantitatively using comparisons with in-situ observations by DMSP along two orbit planes. While the location of EM power input evaluated from Iridium and SuperDARN data is in good agreement with DMSP, the magnitude estimated from DMSP observations is approximately four times larger. Corrected for this underestimate, the total EM power input to the Northern Hemisphere is 188 GW. Comparison of IMAGE FUV-derived distributions of the particle energy flux with DMSP plasma data indicates that the IMAGE FUV results similarly locate the precipitation accurately while underestimating the precipitation input somewhat. The total particle input is estimated to be 20 GW, nearly a factor of ten lower than the EM input. We therefore expect the thermosphere response to be determined primarily by the EM input even under winter conditions, and accurate assessment of the EM energy input is therefore key

  14. Cropland responses to extreme winter temperature events: results from a manipulation experiment in north-eastern Italy

    Science.gov (United States)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2012-04-01

    In the last years, several studies has focused on terrestrial ecosystem response to climate warming. Most of them have been conducted on natural ecosystems (forests or grasslands), but few have considered intensively managed ecosystems such as croplands despite of their global extension. In particular, extreme events, such as temperature changes outside the growing season (winter) when soil is not covered by plants, can have a strong impact on soil respiration, residues decomposition, yield and overall net biome production (NBP). In this study, we investigated the response of soil respiration (total and heterotrophic), aboveground NPP, yield and NBP on a soybean crop (Glycine max (L.) Merr.) due to a manipulated warmer or cooler winter. The experiment was carried out in Beano (46°00' N 13°01'E, Italy). Soil albedo and soil temperature were manipulated by covering soil surface during late winter with a layer of inert ceramized silica gravel. We tested three treatments with three replicates each: cooling (Co; white gravel), warming (W; black gravel), mix (M; black and white 4:1 gravel) and control (C; bare soil). An automated soil respiration system measured continuously total soil CO2 efflux across all the year and heterotrophic respiration after sowing in root exclusion subplots. Additionally, soil temperature profiles (0, 2.5, 5 and 10 cm depth), soil water content (between 5 and 10 cm depth) were monitored in each plot. After sowing, soybean phenological phases were periodically assessed and final yield was measured in each plot. Results showed a significant change in upper soil temperature between gravel application and canopy closure (maximum of + 5.8 °C and - 6.8 °C in the warming and cooling treatments, respectively). However, warming had only a transient effect on soil respiration (increase) before sowing. Thereafter, as soon as fresh organic matter availability decreased, soil respiration rate decreased and annual budget was not significantly different

  15. Gender-Based Experiences and Perceptions after the 2010 Winter Storms in Atlantic Canada

    Directory of Open Access Journals (Sweden)

    Liette Vasseur

    2015-10-01

    Full Text Available This paper conveys the findings of the first phase of a longitudinal study into climate change adaptation in Atlantic Canada. Men and women from 10 coastal communities in three provinces (Quebec, New Brunswick, and Prince Edward Island were interviewed to better understand how both sexes perceived and reacted to extreme weather events. Their responses were recorded based on their experiences, personal and community levels of preparedness, as well as help received and effects on their lives. Most importantly, the findings denote that more men were personally prepared and more active in the community than women. More men recognized a deficiency in help at the community level, and were critical of government in particular, addressing a lack of financial interventions and support. Women were forthcoming with their emotions, admitting to feeling fear and worry, and their perceptions in terms of impacts and actions were closer to home. The results support what others have shown that in rural and coastal communities the traditional division of labor may influence and lead to a gender bias in terms of actions and gradual adaptation in communities. There is a need to better understand how these sometimes subtle differences may affect decisions that do not always consider women’s roles and experiences in the face of extreme events.

  16. Exploring Group Cohesion in a Higher Education Field Experience

    Science.gov (United States)

    Malcarne, Brian Keith

    2012-01-01

    The purpose of this study was to gain understanding into the experience of group cohesion for university students participating in an academic field experience. A mixed methods approach was used following a two-phase, sequential research design to help provide a more complete explanation of how group cohesion was impacted by the field experience.…

  17. Global Hawk dropsonde observations of the Arctic atmosphere obtained during the Winter Storms and Pacific Atmospheric Rivers (WISPAR field campaign

    Directory of Open Access Journals (Sweden)

    J. M. Intrieri

    2014-11-01

    Full Text Available In February and March of 2011, the Global Hawk unmanned aircraft system (UAS was deployed over the Pacific Ocean and the Arctic during the Winter Storms and Pacific Atmospheric Rivers (WISPAR field campaign. The WISPAR science missions were designed to (1 mprove our understanding of Pacific weather systems and the polar atmosphere; (2 evaluate operational use of unmanned aircraft for investigating these atmospheric events; and (3 demonstrate operational and research applications of a UAS dropsonde system at high latitudes. Dropsondes deployed from the Global Hawk successfully obtained high-resolution profiles of temperature, pressure, humidity, and wind information between the stratosphere and surface. The 35 m wingspan Global Hawk, which can soar for ~ 31 h at altitudes up to ~ 20 km, was remotely operated from NASA's Dryden Flight Research Center at Edwards Air Force Base (AFB in California. During the 25 h polar flight on 9–10 March 2011, the Global Hawk released 35 sondes between the North Slope of Alaska and 85° N latitude, marking the first UAS Arctic dropsonde mission of its kind. The polar flight transected an unusually cold polar vortex, notable for an associated record-level Arctic ozone loss, and documented polar boundary layer variations over a sizable ocean–ice lead feature. Comparison of dropsonde observations with atmospheric reanalyses reveal that, for this day, large-scale structures such as the polar vortex and air masses are captured by the reanalyses, while smaller-scale features, including low-level jets and inversion depths, are mischaracterized. The successful Arctic dropsonde deployment demonstrates the capability of the Global Hawk to conduct operations in harsh, remote regions. The limited comparison with other measurements and reanalyses highlights the potential value of Arctic atmospheric dropsonde observations where routine in situ measurements are practically nonexistent.

  18. A modified method for pesticide transport and fate in subsurface environment of a winter wheat field of Yangling, China.

    Science.gov (United States)

    Wu, Lei; Chang, Huanyu; Ma, Xiaoyi

    2017-12-31

    The Guanzhong region is one of the water resources shortage areas and also an important food producing area in Chinese Loess Plateau. The unreasonable application of irrigation and pesticide not only reduces the utilization rate of pesticides, but also is a potential threat to aquatic environments. In order to explore the reasonable application pattern of irrigation and pesticide, a modified method considering crop water requirement and pesticide transport was established to simulate transport and fate of Triadimefon in subsurface environment of a winter wheat field in Yangling, China. Results indicate that: (1) the modified method introduces the concepts of crop water requirement and irrigation schedule, which can estimate irrigation amount more accurately and achieve the goal of water saving and agricultural diffuse pollution control more efficiently. The method shows good potential applications and implications in predicting pesticide exposure levels of different crops and in reducing pesticide pollution. (2) The changing trends of soil pesticide levels under different pesticide applications are various. The Triadimefon concentration level in surface soil layer (0.005m) was directly affected by pesticide application and irrigation. The Triadimefon peak below the soil depth of 0.035m has prominently delayed effects and it is mainly affected by irrigations. The concentration of pesticides decays rapidly with the increase of soil depth, and it can be ignored below the depth of 0.5m. (3) The soil pesticide levels under different pesticide and irrigation modes show considerable differences, the irrigation is still the most significant factor affecting the level of soil pesticide residues under different time intervals between pesticide application and irrigation. The irrigation scheme of one-day interval and five-divided irrigation can effectively reduce deep soil pollution without affecting the normal growth of crops. Results may provide theoretical basis and guide

  19. Biophysical controls on light response of net CO2 exchange in a winter wheat field in the North China Plain.

    Directory of Open Access Journals (Sweden)

    Xiaojuan Tong

    Full Text Available To investigate the impacts of biophysical factors on light response of net ecosystem exchange (NEE, CO2 flux was measured using the eddy covariance technique in a winter wheat field in the North China Plain from 2003 to 2006. A rectangular hyperbolic function was used to describe NEE light response. Maximum photosynthetic capacity (P max was 46.6 ± 4.0 µmol CO2 m(-2 s(-1 and initial light use efficiency (α 0.059 ± 0.006 µmol µmol(-1 in April-May, two or three times as high as those in March. Stepwise multiple linear regressions showed that P max increased with the increase in leaf area index (LAI, canopy conductance (g c and air temperature (T a but declined with increasing vapor pressure deficit (VPD (P25°C or VPD>1.1-1.3 kPa, NEE residual increased with the increase in T a and VPD (P<0.001, indicating that temperature and water stress occurred. When g c was more than 14 mm s(-1 in March and May and 26 mm s(-1 in April, the NEE residuals decline disappeared, or even turned into an increase in g c (P<0.01, implying shifts from stomatal limitation to non-stomatal limitation on NEE. Although the differences between sunny and cloudy sky conditions were unremarkable for light response parameters, simulated net CO2 uptake under the same radiation intensity averaged 18% higher in cloudy days than in sunny days during the year 2003-2006. It is necessary to include these effects in relevant carbon cycle models to improve our estimation of carbon balance at regional and global scales.

  20. Field Trips as Valuable Learning Experiences in Geography Courses

    Science.gov (United States)

    Krakowka, Amy Richmond

    2012-01-01

    Field trips have been acknowledged as valuable learning experiences in geography. This article uses Kolb's (1984) experiential learning model to discuss how students learn and how field trips can help enhance learning. Using Kolb's experiential learning theory as a guide in the design of field trips helps ensure that field trips contribute to…

  1. Cockle Field Caging Experiment Data (2014)

    Data.gov (United States)

    U.S. Environmental Protection Agency — To determine whether differences in cockle density or qualitative burial depth observed during the 2014 field survey were affected by green macroalgal (GMA) mats, we...

  2. Minimizing magnetic fields for precision experiments

    Science.gov (United States)

    Altarev, I.; Fierlinger, P.; Lins, T.; Marino, M. G.; Nießen, B.; Petzoldt, G.; Reisner, M.; Stuiber, S.; Sturm, M.; Taggart Singh, J.; Taubenheim, B.; Rohrer, H. K.; Schläpfer, U.

    2015-06-01

    An increasing number of measurements in fundamental and applied physics rely on magnetically shielded environments with sub nano-Tesla residual magnetic fields. State of the art magnetically shielded rooms (MSRs) consist of up to seven layers of high permeability materials in combination with highly conductive shields. Proper magnetic equilibration is crucial to obtain such low magnetic fields with small gradients in any MSR. Here, we report on a scheme to magnetically equilibrate MSRs with a 10 times reduced duration of the magnetic equilibration sequence and a significantly lower magnetic field with improved homogeneity. For the search of the neutron's electric dipole moment, our finding corresponds to a 40% improvement of the statistical reach of the measurement. However, this versatile procedure can improve the performance of any MSR for any application.

  3. NAVIGATING LIVED EXPERIENCE: REFLECTIONS FROM THE FIELD.

    Directory of Open Access Journals (Sweden)

    Leah Farrall

    2015-09-01

    Full Text Available In this article I use an autoethnographic approach to reflect on my experiences in Egypt—in which I came to live alongside converts to Islam and interact with adherents to militant salafist belief systems, as well as those who had disengaged from them. I outline how I came to have these lived experiences before explaining how they caused me to reexamine my understanding of radicalization and deradicalization in the militant salafist context, and to consider radicalization as a form of conversion.

  4. Entrepreneurship, teams and sustainability: A series of field experiments

    NARCIS (Netherlands)

    Rosendahl Huber, L.

    2015-01-01

    This dissertation reports the results from three field experiments that were conducted within the setting of one of the leading, internationally renowned entrepreneurship education programs for primary schools called BizWorld. The first field experiment evaluates the program’s effectiveness in terms

  5. Airborne ground penetrating radar: practical field experiments

    CSIR Research Space (South Africa)

    Van Schoor, Michael

    2013-10-01

    Full Text Available application of the technique are often challenged. The reasons for experimenting with non-traditional applications may vary, but common themes are productivity and logistics: Ways of overcoming logistical obstacles (for example, survey sites... that are difficult to access on foot) and of acquiring data more productively (for example, where large survey areas need to be covered) are often sought. One way of increasing GPR productivity is to employ multiple sensors simultaneously. Another way...

  6. Tandem mirror and field-reversed mirror experiments

    Energy Technology Data Exchange (ETDEWEB)

    Coensgen, F.H.; Simonen, T.C.; Turner, W.C.

    1979-08-21

    This paper is largely devoted to tandem mirror and field-reversed mirror experiments at the Lawrence Livermore Laboratory (LLL), and briefly summarizes results of experiments in which field-reversal has been achieved. In the tandem experiment, high-energy, high-density plasmas (nearly identical to 2XIIB plasmas) are located at each end of a solenoid where plasma ions are electrostatically confined by the high positive poentials arising in the end plug plasma. End plug ions are magnetically confined, and electrons are electrostatically confined by the overall positive potential of the system. The field-reversed mirror reactor consists of several small field-reversed mirror plasmas linked together for economic reasons. In the LLL Beta II experiment, generation of a field-reversed plasma ring will be investigated using a high-energy plasma gun with a transverse radial magnetic field. This plasma will be further heated and sustained by injection of intense, high-energy neutral beams.

  7. Mechanical weed control in organic winter wheat

    OpenAIRE

    Euro Pannacci; Francesco Tei; Marcello Guiducci

    2017-01-01

    Three field experiments were carried out in organic winter wheat in three consecutive years (exp. 1, 2005-06; exp. 2, 2006- 07; exp. 3, 2007-08) in central Italy (42°57’ N - 12°22’ E, 165 m a.s.l.) in order to evaluate the efficacy against weeds and the effects on winter wheat of two main mechanical weed control strategies: i) spring tine harrowing used at three different application times (1 passage at T1, 2 passages at the time T1, 1 passage at T1 followed by 1 passage at T1 + 14 days) in t...

  8. [Change characteristics of soil moisture and nutrients in rain-fed winter wheat field under different fertilization modes in Southern Shanxi of China during summer fallow period].

    Science.gov (United States)

    Li, Ting-Liang; Xie, Ying-He; Hong, Jian-Ping; Feng, Qian; Sun, Cheng-Hong; Wang, Zhi-Wei

    2013-06-01

    In 2009-2011, a field experiment was conducted in a rain-fed winter wheat field in Southern Shanxi of China to study the effects of different fertilization modes on the change characteristics of soil moisture and nitrate-N contents in 0-200 cm layer and of soil available phosphorus (Oslen-P) and potassium contents in 0-40 cm layer during summer fallow period (from June to September). Three fertilization modes were installed, i. e., conventional fertilization (CF), recommended fertilization (RF), and ridge film furrow planting (RFFP) combined with straw mulch. The results showed that the rainfall in summer fallow period could complement the consumed water in 0-200 cm soil layer in dryland wheat field throughout the growth season, and more than 94% of the water storage was in 0-140 cm soil layer, with the fallow efficiency ranged from 6% to 27%. The rainfall in summer fallow period caused the soil nitrate-N moving downward. 357-400 mm rainfall could make the soil nitrate-N leaching down to 100 cm soil layer, with the peak in 20-40 cm soil layer. Straw mulching or plastic film with straw mulch in summer fallow period could effectively increase the Oslen-P and available K contents in 0-40 cm soil layer, and the accumulative increment in three summer fallow periods was 16-45% and 36-49%, respectively. Among the three modes, the binary coverage mode of RFFP plus furrow straw mulching had the best effect in maintaining soil water and fertility. The accumulative water storage and mineral N in 0-200 cm soil layer in three summer fallow periods were up to 215 mm and 90 kg x hm(-2), and the accumulative Oslen-P and available K contents in plough layer were increased by 2.7 mg x kg(-1) and 83 mg x kg(-1), respectively, being significantly higher than those in treatments CF and RF. There were no significant differences in the change characteristics in the soil moisture and nutrients between treatments CF and RF.

  9. Arctic Observing Experiment (AOX) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Rigor, Ignatius [Applied Physics Lab, University of Washington; Johnson, Jim [Applied Physics Lab, University of Washington; Motz, Emily [National Ice Center; Bisic, Aaron [National Ice Center

    2017-06-30

    Our ability to understand and predict weather and climate requires an accurate observing network. One of the pillars of this network is the observation of the fundamental meteorological parameters: temperature, air pressure, and wind. We plan to assess our ability to measure these parameters for the polar regions during the Arctic Observing Experiment (AOX, Figure 1) to support the International Arctic Buoy Programme (IABP), Arctic Observing Network (AON), International Program for Antarctic Buoys (IPAB), and Southern Ocean Observing System (SOOS). Accurate temperature measurements are also necessary to validate and improve satellite measurements of surface temperature across the Arctic. Support for research associated with the campaign is provided by the National Science Foundation, and by other US agencies contributing to the US Interagency Arctic Buoy Program. In addition to the support provided by the U.S Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s North Slope of Alaska (NSA) site at Barrow and the National Science Foundation (NSF), the U.S. IABP is supported by the U.S. Coast Guard (USCG), the National Aeronautics and Space Administration (NASA), the National Ice Center (NIC), the National Oceanic and Atmospheric Administration (NOAA), and the Office of Naval Research (ONR).

  10. Magnetic field saturation in the Riga dynamo experiment.

    Science.gov (United States)

    Gailitis, A; Lielausis, O; Platacis, E; Dement'ev, S; Cifersons, A; Gerbeth, G; Gundrum, T; Stefani, F; Christen, M; Will, G

    2001-04-02

    After the dynamo experiment in November 1999 [A. Gailitis et al., Phys. Rev. Lett. 84, 4365 (2000)] had shown magnetic field self-excitation in a spiraling liquid metal flow, in a second series of experiments emphasis was placed on the magnetic field saturation regime as the next principal step in the dynamo process. The dependence of the strength of the magnetic field on the rotation rate is studied. Various features of the saturated magnetic field are outlined and possible saturation mechanisms are discussed.

  11. Proton and deuterium NMR experiments in zero field

    International Nuclear Information System (INIS)

    Millar, J.M.

    1986-02-01

    High field solid-state NMR lineshapes suffer from inhomogeneous broadening since resonance frequencies are a function of molecular orientation. Time domain zero field NMR is a two-dimensional field-cycling technique which removes this broadening by probing the evolution of the spin system under zero applied field. The simplest version, the sudden transition experiment, induces zero field evolution by the sudden removal of the applied magnetic field. Theory and experimental results of this experiment and several variations using pulsed dc magnetic fuelds to initiate zero field evolution are presented. In particular, the pulsed indirect detection method allows detection of the zero field spectrum of one nuclear spin species via another (usually protons) by utilizing the level crossings which occur upon adiabatic demagnetization to zero field. Experimental examples of proton/deuteron systems are presented which demonstrate the method results in enhanced sensitivity relative to that obtained in sudden transition experiments performed directly on deuterium. High resolution 2 H NQR spectra of a series of benzoic acid derivatives are obtained using the sudden transition and indirect detection methods. Librational oscillations in the water molecules of barium chlorate monohydrate are studied using proton and deuterium ZF experiments. 177 refs., 88 figs., 2 tabs

  12. A "Medical Physics" Course Based Upon Hospital Field Experience

    Science.gov (United States)

    Onn, David G.

    1972-01-01

    Describes a noncalculus, medical physics'' course with a basic element of direct hospital field experience. The course is intended primarily for premedical students but may be taken by nonscience majors. (Author/PR)

  13. Attention discrimination: theory and field experiments with monitoring information acquisition

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Vojtěch; Bauer, Michal; Chytilová, Julie; Matějka, Filip

    2016-01-01

    Roč. 106, č. 6 (2016), s. 1437-1475 ISSN 0002-8282 Institutional support: RVO:67985998 Keywords : inattention * discrimination * field experiment Subject RIV: AH - Economics Impact factor: 4.026, year: 2016

  14. Field studies on the germination behaviour of black-grass (Alopecurus myosuroides Huds. depending on sowing date und winter wheat variety in Northern Germany

    Directory of Open Access Journals (Sweden)

    Landschreiber, Manja

    2014-02-01

    Full Text Available Black-grass (Alopecurus myosuroides, Huds. is the most important herbicide-resistant weed in Europe. In Germany it is not only a problem in the maritime influenced areas like Schleswig-Holstein and Lower Saxony anymore, as well in other regions black-grass develops to the most important weed in winter wheat and oilseed rape. There are multifaceted reasons for that, one reason are close winter crop rotations and early sowing dates which are economically very attractive for the farmers, another one are herbicide resistances. Black-grass germinates in autumn and in spring, but the main germination period is from late August to early October. If winter wheat is sown early in autumn, the main germination is in parallel to the wheat. Then the weeds can only be managed by culture specific herbicides. The pressure on the herbicides is therefore increasing. Herbicide resistances can be the result. As long as very effective herbicides are available, so that farmers are not dependent on weed biology and plant production weed management measures such as sowing date. Late sowing dates can reduce the black-grass populations, but this option is not attractive to many farmers in Schleswig-Holstein. In mind of the farmers the risk of delayed sowing dates in autumn is too high, because increased rainfall such as can make it difficult to marsh soils sowing, or make impossible. Objective of this trial was the germination of Black-grass to show to two sowing dates. The results of the field trial show, that black-grass populations can be reduced if winter wheat is sown later in autumn.

  15. Testing consumer theory: evidence from a natural field experiment

    OpenAIRE

    Adena, Maja; Huck, Steffen; Rasul, Imran

    2017-01-01

    We present evidence from a natural field experiment designed to shed light on whether individual behavior is consistent with a neoclassical model of utility maximization subject to budget constraints. We do this through the lens of a field experiment on charitable giving. We find that the behavior of at least 80% of individuals, on both the extensive and intensive margins, can be rationalized within a standard neoclassical choice model in which individuals have preferences, defined over own c...

  16. Tolerance of two Bifora radians bieb populations to ALS inhibitors in winter wheat

    DEFF Research Database (Denmark)

    Mennan, Husrev; Streibig, Jens Carl; Ngouajio, Mathieu

    2012-01-01

    BACKGROUND:Bifora radians, an annual weed in winter wheat, is distributed mainly in the Mediterranean area, Asia Minor and the Caucasus. It infests winter-sown crops of the Central Anatolia and Middle Black Sea regions of Turkey. Field experiments in heavily B. radians-infested fields were conduc...

  17. Operational experience gained from the Central Brae subsea field

    International Nuclear Information System (INIS)

    Sapp, S.J.; Gomersall, S.D.

    1994-01-01

    The size of the field discoveries made in the North Sea in recent years has declined dramatically. With the low oil price many small fields are not viable stand alone developments. The North Sea has a large, well developed infrastructure of production facilities and pipelines. With many platforms now operating below optimum production rate, subsea tieback of these small fields utilizing the available processing capacity is the most economically attractive means of development. This paper presents a history of such a field development. The Central Brae field is located within the Brae complex of fields, 155 miles north east of Aberdeen, and has been developed by means of a subsea facility tied back to the Brae Alpha platform. A great deal of experience has been gained through the field development, not only in subsea operations but also in completion and template design and operating philosophy

  18. Winter Wonderlands

    Science.gov (United States)

    Coy, Mary

    2011-01-01

    Listening to people complain about the hardships of winter and the dreariness of the nearly constant gray sky prompted the author to help her sixth graders recognize and appreciate the beauty that surrounds them for nearly five months of the year in western New York. The author opines that if students could see things more artistically, the winter…

  19. Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer

    Science.gov (United States)

    Harlow, Henry J.; Durner, George M.; Regehr, Eric V.; Rourke, Bryan C.; Robles, Manuel; Amstrup, Steven C.; Ben-David, Merav

    2017-01-01

    Abstract When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April–May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these ‘shore’ bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These ‘ice’ bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt. PMID:28835844

  20. Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer

    Science.gov (United States)

    Whiteman, John P.; Harlow, Henry J.; Durner, George M.; Regehr, Eric V.; Rourke, Bryan C.; Robles, Manuel; Amstrup, Steven C.; Ben-David, Merav

    2017-01-01

    When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April–May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these ‘shore’ bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These ‘ice’ bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt.

  1. Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer.

    Science.gov (United States)

    Whiteman, John P; Harlow, Henry J; Durner, George M; Regehr, Eric V; Rourke, Bryan C; Robles, Manuel; Amstrup, Steven C; Ben-David, Merav

    2017-01-01

    When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April-May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these 'shore' bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These 'ice' bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt.

  2. Estimation of Winter Wheat Biomass and Yield by Combining the AquaCrop Model and Field Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Xiuliang Jin

    2016-11-01

    Full Text Available Knowledge of spatial and temporal variations in crop growth is important for crop management and stable crop production for the food security of a country. A combination of crop growth models and remote sensing data is a useful method for monitoring crop growth status and estimating crop yield. The objective of this study was to use spectral-based biomass values generated from spectral indices to calibrate the AquaCrop model using the particle swarm optimization (PSO algorithm to improve biomass and yield estimations. Spectral reflectance and concurrent biomass and yield were measured at the Xiaotangshan experimental site in Beijing, China, during four winter wheat-growing seasons. The results showed that all of the measured spectral indices were correlated with biomass to varying degrees. The normalized difference matter index (NDMI was the best spectral index for estimating biomass, with the coefficient of determination (R2, root mean square error (RMSE, and relative RMSE (RRMSE values of 0.77, 1.80 ton/ha, and 25.75%, respectively. The data assimilation method (R2 = 0.83, RMSE = 1.65 ton/ha, and RRMSE = 23.60% achieved the most accurate biomass estimations compared with the spectral index method. The estimated yield was in good agreement with the measured yield (R2 = 0.82, RMSE = 0.55 ton/ha, and RRMSE = 8.77%. This study offers a new method for agricultural resource management through consistent assessments of winter wheat biomass and yield based on the AquaCrop model and remote sensing data.

  3. Influencing attitudes toward science through field experiences in biology

    Science.gov (United States)

    Carpenter, Deborah Mcintyre

    The purpose of this study was to determine how student attitudes toward science are influenced by field experiences in undergraduate biology courses. The study was conducted using two institutions of higher education including a 2-year lower-level and a 2-year upper-level institution. Data were collected through interviews with student participants, focus group discussions, students' journal entries, and field notes recorded by the researcher during the field activities. Photographs and video recordings were also used as documentation sources. Data were collected over a period of 34 weeks. Themes that emerged from the qualitative data included students' beliefs that field experiences (a) positively influence student motivation to learn, (b) increase student ability to learn the concepts being taught, and (c) provide opportunities for building relationships and for personal growth. The findings of the study reinforce the importance of offering field-study programs at the undergraduate level to allow undergraduate students the opportunity to experience science activities in a field setting. The research study was framed by the behavioral and developmental theories of attitude and experience including the Theory of Planned Behavior (Ajzen, 1991) and the Theory of Experiential Learning (Kolb, 1984).

  4. The AACES field experiments: SMOS calibration and validation across the Murrumbidgee River catchment

    Science.gov (United States)

    Peischl, S.; Walker, J. P.; Rüdiger, C.; Ye, N.; Kerr, Y. H.; Kim, E.; Bandara, R.; Allahmoradi, M.

    2012-06-01

    Following the launch of the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) mission on 2 November 2009, SMOS soil moisture products need to be rigorously validated at the satellite's approximately 45 km scale and disaggregation techniques for producing maps with finer resolutions tested. The Australian Airborne Cal/val Experiments for SMOS (AACES) provide the basis for one of the most comprehensive assessments of SMOS data world-wide by covering a range of topographic, climatic and land surface variability within an approximately 500 × 100 km2 study area, located in South-East Australia. The AACES calibration and validation activities consisted of two extensive field experiments which were undertaken across the Murrumbidgee River catchment during the Australian summer and winter season of 2010, respectively. The datasets include airborne L-band brightness temperature, thermal infrared and multi-spectral observations at 1 km resolution, as well as extensive ground measurements of near-surface soil moisture and ancillary data, such as soil temperature, soil texture, surface roughness, vegetation water content, dew amount, leaf area index and spectral characteristics of the vegetation. This paper explains the design and data collection strategy of the airborne and ground component of the two AACES campaigns and presents a preliminary analysis of the field measurements including the application and performance of the SMOS core retrieval model on the diverse land surface conditions captured by the experiments. The data described in this paper are publicly available from the website: http://www.moisturemap.monash.edu.au/aaces.

  5. Electronic journal management systems experiences from the field

    CERN Document Server

    Ives, Gary W

    2013-01-01

    Discover how to manage your library's electronic journals?with tips from those who've already met the challenge!The explosive growth of electronic journals presents unique challenges for libraries. Electronic Journal Management Systems: Experiences from the Field comprehensively examines these complex topics, including explanations of the automated systems libraries have developed or adopted, licensing issues, and the provision of access to electronic journals. Respected library professionals discuss their own experiences in the implementation and use of electronic journal management systems,

  6. Experiments on plasma turbulence induced by strong, steady electric fields

    International Nuclear Information System (INIS)

    Hamberger, S.M.

    1975-01-01

    The author discusses the effect of applying a strong electric field to collisionless plasma. In particular are compared what some ideas and prejudices lead one to expect to happen, what computer simulation experiments tell one ought to happen, and what actually does happen in two laboratory experiments which have been designed to allow the relevant instability and turbulent processes to occur unobstructed and which have been studied in sufficient detail. (Auth.)

  7. The Passy-2015 field experiment: wintertime atmospheric dynamics and air quality in a narrow alpine valley

    Science.gov (United States)

    Paci, Alexandre; Staquet, Chantal

    2016-04-01

    Wintertime anticyclonic conditions lead to the formation of persistent stable boundary layers which may induce severe air pollution episodes in urban or industrialized area, particularly in mountain regions. The Arve river valley in the Northern Alps is very sensitive to this phenomenon, in particular close to the city of Passy (Haute-Savoie), 20 km down valley past Chamonix. This place is indeed one of the worst place in France regarding air quality, the concentration of fine particles and Benzo(a)pyrene (a carcinogenic organic compound) regularly exceeding the EU legal admissible level during winter. Besides air quality measurements, such as the ones presently carried in the area by the local air quality agency Air Rhône-Alpes or in the DECOMBIO project led by LGGE, it is crucial to improve our knowledge of the atmospheric boundary layer dynamics and processes at the valley scale under these persistent stable conditions in order to improve our understanding on how it drives pollutant dispersion. These issues motivated the Passy-2015 field experiment which took place during the winter 2014-2015. A relatively large set-up of instruments was deployed on a main measurement site in the valley center and on four other satellite sites. It includes several remote sensing instruments, a surface flux station, a 10 m instrumented tower, a large aperture scintillometer, a fog monitoring station among others. Most of the instruments were present from early January to the end of February. During two intensive observation periods, 6-14 February and 17-20 February, the instrumental set-up was completed on the main site with high frequency radio-soundings (up to one per 1h30), a tethered balloon, a remote controlled drone quadcopter and a sodar. The field campaign, the instruments, the meteorological situations observed and preliminary results will be presented. This field experiment is part of the Passy project funded by ADEME through the French national programme LEFE/INSU and

  8. Lidar Atmopheric Sensing Experiment (LASE) Data Obtained During the Southern Great Plains (SGP97) Field Experiment

    Data.gov (United States)

    National Aeronautics and Space Administration — The LASE Southern Great Plains (SGP97) field experiment was conducted in Oklahoma during June-July 1997. SGP97 was a NASA EOS Interdisciplinary Science Investigation...

  9. Rational Ignorance in Education: A Field Experiment in Student Plagiarism

    Science.gov (United States)

    Dee, Thomas S.; Jacob, Brian A.

    2012-01-01

    Plagiarism appears to be a common problem among college students, yet there is little evidence on the effectiveness of interventions designed to minimize plagiarism. This study presents the results of a field experiment that evaluated the effects of a web-based educational tutorial in reducing plagiarism. We found that assignment to the treatment…

  10. Violent conflict and behavior : A field experiment in Burundi

    NARCIS (Netherlands)

    Voors, M.J.; Nillesen, E.E.M.; Verwimp, P.; Bulte, E.H.; Lensink, B.W.; van Soest, D.P.

    We use a series of field experiments in rural Burundi to examine the impact of exposure to conflict on social, risk, and time preferences. We find that conflict affects behavior: individuals exposed to violence display more altruistic behavior towards their neighbors, are more risk-seeking, and have

  11. Ethnic diversity and team performance: a field experiment

    NARCIS (Netherlands)

    Hoogendoorn, S.; van Praag, M.

    2012-01-01

    One of the most salient and relevant dimensions of team heterogeneity is ethnicity. We measure the causal impact of ethnic diversity on the performance of business teams using a randomized field experiment. We follow 550 students who set up 45 real companies as part of their curriculum in an

  12. Diversity and team performance: A series of field experiments

    NARCIS (Netherlands)

    Hoogendoorn, S.M.

    2013-01-01

    This dissertation studies the impact of diversity on team performance using a series of field experiments in which teams start up and manage real companies under identical circumstances. Exogenous variation in - otherwise random - team composition is imposed by assigning individuals to teams based

  13. Attention discrimination: theory and field experiments with monitoring information acquisition

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Vojtěch; Bauer, M.; Chytilová, J.; Matějka, Filip

    2016-01-01

    Roč. 106, č. 6 (2016), s. 1437-1475 ISSN 0002-8282 R&D Projects: GA ČR(CZ) GA14-30724S Institutional support: PRVOUK-P23 Keywords : inattention * discrimination * field experiment Subject RIV: AH - Economics Impact factor: 4.026, year: 2016

  14. Dynamic Incentive Effects of Relative Performance Pay: A Field Experiment

    NARCIS (Netherlands)

    J. Delfgaauw (Josse); A.J. Dur (Robert); J.A. Non (Arjan); W.J.M.I. Verbeke (Willem)

    2010-01-01

    textabstractWe conduct a field experiment among 189 stores of a retail chain to study dynamic incentive effects of relative performance pay. Employees in the randomly selected treatment stores could win a bonus by outperforming three comparable stores from the control group over the course of four

  15. Does insecticide application in a winter oilseed rape field influence the abundance of pollen beetle Meligethes aeneus in nearby ornamental flowers and vegetables?

    Science.gov (United States)

    Ahmed, Nur; Englund, Jan-Eric; Johansson, Eva; Åhman, Inger

    2013-11-01

    Pollen beetle is a pest that attacks oilseed rape as well as many other brassicaceous crops, garden vegetables and ornamental flowers. The present study was primarily carried out to investigate whether insecticide application in brassicaceous field crops might influence the abundance of pollen beetles in nearby private garden flowers and vegetables. At peak emergence of the new generation of pollen beetles, a significantly higher number of beetles were found in flowers, and in window traps, alongside untreated as opposed to alongside treated sections of the winter oilseed rape (WOSR) field. However, the type of flower played a role in the number of pollen beetles found in the flowers. The presence of pollen beetles in both ornamental and wild flowers was also significantly influenced by the direction of placement of the flowers. No pollen beetle, neither overwintering nor newly emerged, was observed in any of the brassicaceous vegetables placed along the field. The number of pollen beetles in the WOSR field strongly influenced the number of pollen beetles in nearby flowers of preference to the beetles, and insecticide treatment with Biscaya (thiacloprid) against pollen beetle in oilseed rape may thus help, indirectly, to protect nearby garden flowers from damage. © 2013 Society of Chemical Industry.

  16. Laboratory and Field Experiments on Expulsion of Selected Ions along Divergent Polar Geomagnetic Fields

    Science.gov (United States)

    Wong, A. Y.; Deng, B.; Quon, B.; Wang, R.; Hartzell, J.; Rosenthal, G.; Hazelton, L. R.

    2007-12-01

    Laboratory and Field Experiments on Expulsion of Selected Ions along Divergent Polar Geomagnetic Fields. Laboratory experiments have shown significant gyro-resonance acceleration of minority ion species in a magnetized plasma. Field aligned elctron drifts can provide free energy needed to make this process efficient. The linear magnetized device has a uniform magnetic field linked to two adjustable mirrors at the ends. Outdoor experiments at HIPAS Facility Ak(1) ( 84 MW ERP ) are used to test this process in the earth's "chimneys" at the two poles. The divergent polar geomagnetic field converts the perpendicular ion velocity into an upward motion. Satellites and ground-based ELF receivers,supplemented by UHF radars, LIDARs and infrared diagnostics , will monitor low-frequency EM waves and upflows of ions. The upward transport of ions in the lower atmosphere by field-induced diffusion and convection and the coupling to the free energy in the auroral region will be discussed. Computer modeling and theoeries complement our experiments. 1. Wong, A.Y. et al. AIP CIP 96-27719, Chap 3, pp 41-75, 1997

  17. Seasonal migration, vertical activity and winter temperature experience of Greenland halibut Reinhardtius hippoglossoides (Walbaum) in West Greenland waters

    DEFF Research Database (Denmark)

    Boje, Jesper; Neuenfeldt, Stefan; Sparrevohn, Claus Reedtz

    2014-01-01

    little is known about its behavior and habitat characteristics. We tagged adult Greenland halibut in the waters off Ilulissat with electronic data storage tags that collected information on depth, temperature, and time. Although clear differences between individuals in migration and vertical behavior...... were present, we discovered a consistent seasonal migration from the relatively shallow-water Disko Bay area into the deep waters of the Ilulissat Icefjord, where the fish resided in the winter months before returning to Disko Bay. Vertical activity was pronounced at both locations, with fish covering...... resident in Disko Bay (mean range 2.6°C) than when resident in the ice fjord (mean range 1.4°C). Using the tagged halibut as a 'live tool,' we show that parts of the ice fjord are hundreds of meters deeper than previously thought. We also document the first seawater temperature measurements made beneath...

  18. Field and laboratory tests of etched track detectors for 222Rn: summer-vs-winter variations and tightness effects in Maine houses

    International Nuclear Information System (INIS)

    Hess, C.T.; Fleischer, R.L.; Turner, L.G.

    1985-01-01

    Effects of tightness of homes of bedrock character on indoor 222 Rn concentrations were sought in 70 homes in the state of Maine by means of four 6- to 8-month-long surveys over a 1.5-yr period. Laboratory experiments were also performed that document the reliability of the track etching system used for the measurements. In this survey the Rn in tight homes was on the average 3.5 times that in drafty ones, and areas with granitic bedrock led to homes having 2.3 times the Rn as for homes on chlorite-biotite-rich bedrock. Winter-to-summer ratios ranged from 0.5-7, and averaged 1.5, implying that surveys of individual homes require a full year of monitoring

  19. The electromagnetic bio-field: clinical experiments and interferences.

    Science.gov (United States)

    Burnei, G; Hodorogea, D; Georgescu, I; Gavriliu, Ş; Drăghici, I; Dan, D; Vlad, C; Drăghici, L

    2012-06-12

    One of the most important factors is the technical and scientifically rapid development that is continually modifying the world we live in and polluting it with electromagnetic radiations. A functional and structural influence of magnetic and electromagnetic field on living organisms is presented in the literature by many performed experiments. The notion of bio-field represents the electromagnetic field generated by the bio-structures, not only in their normal physiological activities but also in their pathological states. There is a tight interdependency between the bio-field and the bio-structure, which respects the primary notion of an electromagnetic field given by the Maxwell-Faraday laws, in which, the electromagnetic phenomena are simplified to the field variations. These variations can be expressed in a coherent differential equation system that bounds the field vectors to different space points at different time moments. The living organisms cannot contain electrostatic and magneto-static fields due to the intense activity of the bio-structures. The biochemical reactions that have high rhythms and speeds always impose the electrodynamics character of the biologic field that also corresponds to the stability of the protein molecule that can be explained only through a dynamic way. The existent energy is not considered an exciting agent, and it does not lead to any effects. The parameters of these elementary bio-fields cannot yet be fully known due to technical reasons. The biological structures are very complex ones and undergo continuous dynamical activity. That is why the calculus model should be related to the constant dynamics, nowadays being very difficult to express.

  20. User experiences with editorial control in online newspaper comment fields

    DEFF Research Database (Denmark)

    Løvlie, Anders Sundnes; Ihlebæk, Karoline Andrea; Larsson, Anders Olof

    2017-01-01

    This article investigates user experiences with editorial control in online newspaper comment fields following the public backlash against online comments after the 2011 terror attacks in Norway. We analyze data from a survey of online news consumers focusing on experiences and attitudes towards...... editorial control set against a spectrum between “interventionist” and “noninterventionist” positions. Results indicate that interventionist respondents rate the quality of online comments as poor, whereas noninterventionist respondents have most often experienced being the target of editorial control...

  1. Incorporating dynamic root growth enhances the performance of Noah-MP at two contrasting winter wheat field sites

    Science.gov (United States)

    Gayler, Sebastian; Wöhling, Thomas; Ingwersen, Joachim; Wizemann, Hans-Dieter; Warrach-Sagi, Kirsten; Attinger, Sabine; Streck, Thilo; Wulmeyer, Volker

    2014-05-01

    Interactions between the soil, the vegetation, and the atmospheric boundary layer require close attention when predicting water fluxes in the hydrogeosystem, agricultural systems, weather and climate. However, land-surface schemes used in large scale models continue to show deficits in consistently simulating fluxes of water and energy from the subsurface through vegetation layers to the atmosphere. In this study, the multi-physics version of the Noah land-surface model (Noah-MP) was used to identify the processes, which are most crucial for a simultaneous simulation of water and heat fluxes between land-surface and the lower atmosphere. Comprehensive field data sets of latent and sensible heat fluxes, ground heat flux, soil moisture, and leaf area index from two contrasting field sites in South-West Germany are used to assess the accuracy of simulations. It is shown that an adequate representation of vegetation-related processes is the most important control for a consistent simulation of energy and water fluxes in the soil-plant-atmosphere system. In particular, using a newly implemented sub-module to simulate root growth dynamics has enhanced the performance of Noah-MP at both field sites. We conclude that further advances in the representation of leaf area dynamics and root/soil moisture interactions are the most promising starting points for improving the simulation of feedbacks between the sub-soil, land-surface and atmosphere in fully-coupled hydrological and atmospheric models.

  2. Effect of winter cold duration on spring phenology of the orange tip butterfly, Anthocharis cardamines.

    Science.gov (United States)

    Stålhandske, Sandra; Lehmann, Philipp; Pruisscher, Peter; Leimar, Olof

    2015-12-01

    The effect of spring temperature on spring phenology is well understood in a wide range of taxa. However, studies on how winter conditions may affect spring phenology are underrepresented. Previous work on Anthocharis cardamines (orange tip butterfly) has shown population-specific reaction norms of spring development in relation to spring temperature and a speeding up of post-winter development with longer winter durations. In this experiment, we examined the effects of a greater and ecologically relevant range of winter durations on post-winter pupal development of A. cardamines of two populations from the United Kingdom and two from Sweden. By analyzing pupal weight loss and metabolic rate, we were able to separate the overall post-winter pupal development into diapause duration and post-diapause development. We found differences in the duration of cold needed to break diapause among populations, with the southern UK population requiring a shorter duration than the other populations. We also found that the overall post-winter pupal development time, following removal from winter cold, was negatively related to cold duration, through a combined effect of cold duration on diapause duration and on post-diapause development time. Longer cold durations also lead to higher population synchrony in hatching. For current winter durations in the field, the A. cardamines population of southern UK could have a reduced development rate and lower synchrony in emergence because of short winters. With future climate change, this might become an issue also for other populations. Differences in winter conditions in the field among these four populations are large enough to have driven local adaptation of characteristics controlling spring phenology in response to winter duration. The observed phenology of these populations depends on a combination of winter and spring temperatures; thus, both must be taken into account for accurate predictions of phenology.

  3. Field Experiments with Artificial Aerosols at San Nicolas Island, California.

    Science.gov (United States)

    1981-10-28

    idiontlp by block rNmsbeo) Salty Dog Diffusion Aerosol Hygroscopic nuclei Helicopter Extinction Scattering coefficient Fog Relative humidity...Visibility 14ume Infrared 20. AIS_ A1T (Conirnue as eves side if necooeeery asd identfy by block number) -2Artificial fogs grown on hygroscopic (Salty Dog ...Dist Special Field Experiments with Artificial Aerosols at San Nicolas Island, California INTRODUCTION The marine environment offers unique advantages in

  4. Tuning the Mass of Chameleon Fields in Casimir Force Experiments

    CERN Document Server

    Brax, Ph; Davis, A C; Shaw, D J; Iannuzzi, D

    2010-01-01

    We have calculated the chameleon pressure between two parallel plates in the presence of an intervening medium that affects the mass of the chameleon field. As intuitively expected, the gas in the gap weakens the chameleon interaction mechanism with a screening effect that increases with the plate separation and with the density of the intervening medium. This phenomenon might open up new directions in the search of chameleon particles with future long range Casimir force experiments.

  5. Targets with thin ferromagnetic layers for transient field experiments

    International Nuclear Information System (INIS)

    Gallant, J.L.; Dmytrenko, P.

    1982-01-01

    Multilayer targets containing a central layer sufficiently thin so that all recoil nuclei can traverse it and subsequently stop in a suitable cubic environment have been prepared. Such targets are required in experiments making use of a magnetic field acting on an ion moving through a ferromagnetic material. The preparation and annealing of the ferromagnetic foils (iron and gadolinium) and the fabrication of the multilayer targets are described. (orig.)

  6. An Integral, Multidisciplinary and Global Geophysical Field Experience for Undergraduates

    Science.gov (United States)

    Vázquez, O.; Carrillo, D. J.; Pérez-Campos, X.

    2007-05-01

    The udergraduate program of Geophysical Engineering at the School of Engineering, of the Univesidad Nacional Autónoma de México (UNAM), went through an update process that concluded in 2006. As part of the program, the student takes three geophysical prospecting courses (gravity and magnetics, electric, electromagnetics, and seismic methods). The older program required a three-week field experience for each course in order to gradute. The new program considers only one extended field experience. This work stresses the importance of international academic exchange, where undergraduate students could participate, such as the Summer of Applied Geophysical Experience (SAGE), and interaction with research programs, such as the MesoAmerican Subduction Experiment (MASE). Also, we propose a scheeme for this activity based on those examples; both of them have in common real geophysical problems, from which students could benefit. Our proposal covers academic and logistic aspects to be taken into account, enhancing the relevance of interaction between other academic institutions, industry, and UNAM, in order to obtain a broader view of geophysics.

  7. Acoustic experience shapes female mate choice in field crickets

    Science.gov (United States)

    Bailey, Nathan W; Zuk, Marlene

    2008-01-01

    Female choice can drive the evolution of extravagant male traits. In invertebrates, the influence of prior social experience on female choice has only recently been considered. To better understand the evolutionary implications of experience-mediated plasticity in female choice, we investigated the effect of acoustic experience during rearing on female responsiveness to male song in the field cricket Teleogryllus oceanicus. Acoustic experience has unique biological relevance in this species: a morphological mutation has rendered over 90 per cent of males on the Hawaiian island of Kauai silent in fewer than 20 generations, impeding females' abilities to locate potential mates. Females reared in silent conditions mimicking Kauai were less discriminating of male calling song and more responsive to playbacks, compared with females that experienced song during rearing. Our results to our knowledge, are the first demonstration of long-term effects of acoustic experience in an arthropod, and suggest that female T. oceanicus may be able to compensate for the reduced availability of long-range male sexual signals by increasing their responsiveness to the few remaining signallers. Understanding the adaptive significance of experience-mediated plasticity in female choice provides insight into processes that facilitate rapid evolutionary change and shape sexual selection pressure in natural populations. PMID:18700205

  8. Dark matter effective field theory scattering in direct detection experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schneck, K.; Cabrera, B.; Cerdeño, D. G.; Mandic, V.; Rogers, H. E.; Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Caldwell, D. O.; Calkins, R.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D. M.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Saab, T.; Sadoulet, B.; Sander, J.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yang, X.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2015-05-18

    We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  9. On a distribution of electric fields caused by the northern component of the interplanetary magnetic field in the absence of longitudinal currents in the winter polar cap

    International Nuclear Information System (INIS)

    Uvarov, V.M.

    1984-01-01

    Data on the distribution of electric fields, conditioned by the northern component of the interplanetary magnetic field Bsub(z), have been discussed. The problem of electric field excitation is reduced to the solution of equations of continuity for the current in three regions: northern and southern polar caps and region beyond the caps. At the values Bsub(z)>0 in the ranqe of latitudes phi >= 80 deg the localization of convection conversion effect is obtained in calculations for summer cap and it agrees with the data of direct measurements

  10. Atmospheric Radiation Measurement Madden-Julian Oscillation Investigation Experiment Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Long, Chuck [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). Earth System Research Lab.

    2016-07-01

    Every 30–90 days during the Northern Hemisphere winter, the equatorial tropical atmosphere experiences pulses of extraordinarily strong deep convection and rainfall. This phenomenon is referred to as the Madden–Julian Oscillation, or MJO, named after the scientists who identified this cycle. The MJO significantly affects weather and rainfall patterns around the world (Zhang 2013). To improve predictions of the MJO—especially about how it forms and evolves throughout its lifecycle—an international group of scientists collected an unprecedented set of observations from the Indian Ocean and western Pacific region from October 2011 through March 2012 through several coordinated efforts. The coordinated field campaigns captured six distinct MJO cycles in the Indian Ocean. The rich set of observations capturing several MJO events from these efforts will be used for many years to study the physics of the MJO. Here we highlight early research results using data from the Atmospheric Radiation Measurement (ARM) Madden-Julian Oscillation Investigation Experiment (AMIE), sponsored by the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility.

  11. Applying Neural Networks to Hyperspectral and Multispectral Field Data for Discrimination of Cruciferous Weeds in Winter Crops

    Directory of Open Access Journals (Sweden)

    Ana-Isabel de Castro

    2012-01-01

    Full Text Available In the context of detection of weeds in crops for site-specific weed control, on-ground spectral reflectance measurements are the first step to determine the potential of remote spectral data to classify weeds and crops. Field studies were conducted for four years at different locations in Spain. We aimed to distinguish cruciferous weeds in wheat and broad bean crops, using hyperspectral and multispectral readings in the visible and near-infrared spectrum. To identify differences in reflectance between cruciferous weeds, we applied three classification methods: stepwise discriminant (STEPDISC analysis and two neural networks, specifically, multilayer perceptron (MLP and radial basis function (RBF. Hyperspectral and multispectral signatures of cruciferous weeds, and wheat and broad bean crops can be classified using STEPDISC analysis, and MLP and RBF neural networks with different success, being the MLP model the most accurate with 100%, or higher than 98.1%, of classification performance for all the years. Classification accuracy from hyperspectral signatures was similar to that from multispectral and spectral indices, suggesting that little advantage would be obtained by using more expensive airborne hyperspectral imagery. Therefore, for next investigations, we recommend using multispectral remote imagery to explore whether they can potentially discriminate these weeds and crops.

  12. Field experiment on multicomponent ion exchange in a sandy aquifer

    International Nuclear Information System (INIS)

    Bjerg, P.L.; Christensen, T.H.

    1990-01-01

    A field experiment is performed in a sandy aquifer in order to study ion exchange processes and multicomponent solute transport modeling. An injection of groundwater spiked with sodium and potassium chloride was performed over a continuous period of 37 days. The plume is monitored by sampling 350 filters in a spatial grid. The sampling aims at establishing compound (calcium, magnesium, potassium, sodium, chloride) breakthrough curves at various filters 15 to 100 m from the point of injection and areal distribution maps at various cross sections from 0 to 200 m from the point of injection. A three-dimensional multicomponent solute transport model will be used to model the field experiments. The chemical model includes cation exchange, precipitation, dissolution, complexation, ionic strength and the carbonate system. Preliminary results from plume monitoring show that the plume migration is relatively well controlled considering the scale and conditions of the experiment. The transverse dispersion is small causing less dilution than expected. The ion exchange processes have an important influence on the plume composition. Retardation of the injected ions is substantial, especially for potassium. Calcium exhibits a substantial peak following chloride due to release from the ion exchange sites on the sediment. (Author) (8 refs., 5 figs., tab.)

  13. The meaning of nuclear winter

    International Nuclear Information System (INIS)

    Geiger, H.J.

    1987-01-01

    In this paper the author reviews the history and origins of the basic ideas underlying nuclear winter; and findings and predictions of several groups regarding this topic. The author reviews some of the further developments and scientific analyses regarding nuclear winter since the initial announcements of 1983, touching on some of the revisions and controversies and trying to indicate the current status of the field

  14. Brine Migration in Heated Salt: Lessons Learned from Field Experiments

    Science.gov (United States)

    Kuhlman, K. L.; Matteo, E. N.; Mills, M.

    2017-12-01

    We summarize several interesting brine migration related phenomena hinted at in field experiments from field testing related to salt radioactive waste repositories in Germany and the US. Past heater tests in salt have shown 1) thermal-hydrological-mechanical coupling is quite strong during both heating and cooling; 2) chemical composition of brine evolves during heating, and comprises a mix of several water sources; and 3) acid gas (HCl) generation has been observed during past heater tests and may have multiple mechanisms for formation. We present a heated brine migration test design, formulated with these complexities in mind. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  15. Magnetic Field Design for the LANL nEDM Experiment

    Science.gov (United States)

    Dadisman, Ryan

    2017-09-01

    A recent UCN source upgrade at LANSCE makes possible an order of magnitude advancement in the measurement of the neutron electric dipole moment by use of the familiar Ramsey method of separated oscillatory fields. A highly uniform B0 magnetic field is required to achieve sufficiently long spin-relaxation times and to suppress the false EDM caused by the geometric phase effect. We identified a multi-gap solenoid as an ideal candidate to simultaneously achieve the uniformity requirements, via optimization of the gap lengths between and current within different sections, and provide plentiful access to the fiducial region. Results from initial tests of the coil when installed in the magnetic shield house enclosing the experiment will be presented. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Award Number DE-SC-0014622.

  16. WINTER SAECULUM

    Directory of Open Access Journals (Sweden)

    Emil Mihalina

    2017-03-01

    Full Text Available Accumulated imbalances in the economy and on the markets cause specific financial market dynamics that have formed characteristic patterns kept throughout long financial history. In 2008 Authors presented their expectations of key macroeconomic and selected asset class markets developments for period ahead based on Saeculum theory. Use of term Secular describes a specific valuation environment during prolonged period. If valuations as well as selected macro variables are considered as a tool for understanding business cycles then market cycles become much more obvious and easily understandable. Therefore over the long run, certain asset classes do better in terms of risk reward profile than others. Further on, there is no need for frequent portfolio rebalancing and timing of specific investment positions within a particular asset class market. Current stage in cycle development suggests a need for reassessment of trends and prevailing phenomena due to cyclical nture of long lasting Saeculums. Paper reviews developments in recognizable patterns of selected metrics in current Winter Saeculum dominated with prevailing forces of delivering, deflation and decrease in velocity of money.

  17. Cartoon music in a candy store: a field experiment.

    Science.gov (United States)

    Le Guellec, Hélène; Guéguen, Nicolas; Jacob, Céline; Pascual, Alexandre

    2007-06-01

    An experiment on consumers' behavior was carried out in a new field context. According to a random assignment, 60 customers from ages 12 to 14 years who entered a candy store were exposed to Top Forty music which was usually played in this store, music from cartoons (Captain Flame, Candy, Olive & Tom, etc.), or no music. Analysis showed that customers spent significantly more time in the store when cartoon music was played, but the two styles of music were not related to the amount of money spent.

  18. Insect monitoring with fluorescence lidar techniques: field experiments.

    Science.gov (United States)

    Guan, Zuguang; Brydegaard, Mikkel; Lundin, Patrik; Wellenreuther, Maren; Runemark, Anna; Svensson, Erik I; Svanberg, Sune

    2010-09-20

    Results from field experiments using a fluorescence lidar system to monitor movements of insects are reported. Measurements over a river surface were made at distances between 100 and 300 m, detecting, in particular, damselflies entering the 355 nm pulsed laser beam. The lidar system recorded the depolarized elastic backscattering and two broad bands of laser-induced fluorescence, with the separation wavelength at 500 nm. Captured species, dusted with characteristic fluorescent dye powders, could be followed spatially and temporally after release. Implications for ecological research are discussed.

  19. Incineration in the nuclear field. The SGN experience

    International Nuclear Information System (INIS)

    Carpentier, S.

    1993-01-01

    The operation of power reactors, like that of fuel fabrication and nuclear fuel reprocessing plants, generated substantial quantities of waste. A large share of this waste is low- and medium-level waste, which is also combustible. Similarly, a number of institutes, laboratories, and hospitals, in the course of their activities, generated waste which a portion is radioactive and combustible. The chief advantage of incineration is to minimize the volume of burnable waste treated, and to produce a residue termed 'ash'. SGN has built up 25 years of experience in this field. The incinerators have been designed and the incineration processes are specially studied by SGN

  20. Experiments of cylindrical isentropic compression by ultrahigh magnetic field

    Science.gov (United States)

    Gu, Zhuowei; Zhou, Zhongyu; Zhang, Chunbo; Tang, Xiaosong; Tong, Yanjin; Zhao, Jianheng; Sun, Chengwei

    2015-09-01

    The high Explosive Magnetic Flux Implosion Compression Generator (EMFICG) is a kind of unique high energy density dynamic technique with characters like ultrahigh pressure and low temperature rising and could be suitable as a tool of cylindrical isentropic compression. The Institute of Fluid Physics, Chinese Academy of Engineering Physics (IFP, CAEP) have developed EMFICG technique and realized cylindrical isentropic compression. In the experiments, a seed magnetic field of 5-6 Tesla were built first and compressed by a stainless steel liner which is driven by high explosive. The inner free surface velocity of sample was measured by PDV. The isentropic compression of a copper sample was verified and the isentropic pressure is over 100 GPa. The cylindrical isentropic compression process has been numerical simulated by 1D MHD code and the simulation results were compared with the experiments. Compared with the transitional X-ray flash radiograph measurement, this method will probably promote the data accuracy.

  1. Experiments of cylindrical isentropic compression by ultrahigh magnetic field

    Directory of Open Access Journals (Sweden)

    Gu Zhuowei

    2015-01-01

    Full Text Available The high Explosive Magnetic Flux Implosion Compression Generator (EMFICG is a kind of unique high energy density dynamic technique with characters like ultrahigh pressure and low temperature rising and could be suitable as a tool of cylindrical isentropic compression. The Institute of Fluid Physics, Chinese Academy of Engineering Physics (IFP, CAEP have developed EMFICG technique and realized cylindrical isentropic compression. In the experiments, a seed magnetic field of 5–6 Tesla were built first and compressed by a stainless steel liner which is driven by high explosive. The inner free surface velocity of sample was measured by PDV. The isentropic compression of a copper sample was verified and the isentropic pressure is over 100 GPa. The cylindrical isentropic compression process has been numerical simulated by 1D MHD code and the simulation results were compared with the experiments. Compared with the transitional X-ray flash radiograph measurement, this method will probably promote the data accuracy.

  2. On Storks and Babies: Correlation, Causality and Field Experiments

    Directory of Open Access Journals (Sweden)

    Lambrecht Anja

    2016-11-01

    Full Text Available The explosion of available data has created much excitement among marketing practitioners about their ability to better understand the impact of marketing investments. Big data allows for detecting patterns and often it seems plausible to interpret them as causal. While it is quite obvious that storks do not bring babies, marketing relationships are usually less clear. Apparent “causalities” often fail to hold up under examination. If marketers want to be sure not to walk into a causality trap, they need to conduct field experiments to detect true causal relationships. In the present digital environment, experiments are easier than ever to execute. However, they need to be prepared and interpreted with great care in order to deliver meaningful and genuinely causal results that help improve marketing decisions.

  3. SRNL RADIONUCLIDE FIELD LYSIMETER EXPERIMENT: BASELINE CONSTRUCTION AND IMPLEMENTATION

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, K.; Kaplan, D.; Bagwell, L.; Powell, B.; Almond, P.; Emerson, H.; Hixon, A.; Jablonski, J.; Buchanan, C.; Waterhouse, T.

    2012-10-17

    The purpose of this document is to compile information regarding experimental design, facility design, construction, radionuclide source preparation, and path forward for the ten year Savannah River National Laboratory (SRNL) Radionuclide Field Lysimeter Experiment at the Savannah River Site (SRS). This is a collaborative effort by researchers at SRNL and Clemson University. The scientific objectives of this study are to: Study long-term radionuclide transport under conditions more representative of vadose zone conditions than laboratory experiments; Provide more realistic quantification of radionuclide transport and geochemistry in the vadose zone, providing better information pertinent to radioactive waste storage solutions than presently exists; Reduce uncertainty and improve justification for geochemical models such as those used in performance assessments and composite analyses.

  4. Genetic analysis of bolting after winter in sugar beet (Beta vulgaris L.).

    Science.gov (United States)

    Pfeiffer, Nina; Tränkner, Conny; Lemnian, Ioana; Grosse, Ivo; Müller, Andreas E; Jung, Christian; Kopisch-Obuch, Friedrich J

    2014-11-01

    This study reveals for the first time a major QTL for post-winter bolting resistance in sugar beet ( Beta vulgaris L.). The knowledge of this QTL is a major contribution towards the development of a winter sugar beet with controlled bolting behavior. In cool temperate climates, sugar beets are currently grown as a spring crop. They are sown in spring and harvested in autumn. Growing sugar beet as a winter crop with an extended vegetation period fails due to bolting after winter. Bolting after winter might be controlled by accumulating genes for post-winter bolting resistance. Previously, we had observed in field experiments a low post-winter bolting rate of 0.5 for sugar beet accession BETA 1773. This accession was crossed with a biennial sugar beet with regular bolting behavior to develop a F3 mapping population. The population was grown in the greenhouse, exposed to artificial cold treatment for 16 weeks and transplanted to the field. Bolting was recorded twice a week from May until October. Post-winter bolting behavior was assessed by two different factors, bolting delay (determined as days to bolt after cold treatment) and post-winter bolting resistance (bolting rate after winter). For days to bolt, means of F3 families ranged from 25 to 164 days while for bolting rate F3 families ranged from 0 to 1. For each factor one QTL explaining about 65% of the phenotypic variation was mapped to the same region on linkage group 9 with a partially recessive allele increasing bolting delay and post-winter bolting resistance. The results are discussed in relation to the potential use of marker-assisted breeding of winter sugar beets with controlled bolting.

  5. Alkali Rydberg states in electromagnetic fields: computational physics meets experiment

    International Nuclear Information System (INIS)

    Krug, A.

    2001-11-01

    We study highly excited hydrogen and alkali atoms ('Rydberg states') under the influence of a strong microwave field. As the external frequency is comparable to the highly excited electron's classical Kepler frequency, the external field induces a strong coupling of many different quantum mechanical energy levels and finally leads to the ionization of the outer electron. While periodically driven atomic hydrogen can be seen as a paradigm of quantum chaotic motion in an open (decaying) quantum system, the presence of the non-hydrogenic atomic core - which unavoidably has to be treated quantum mechanically - entails some complications. Indeed, laboratory experiments show clear differences in the ionization dynamics of microwave driven hydrogen and non-hydrogenic Rydberg states. In the first part of this thesis, a machinery is developed that allows for numerical experiments on alkali and hydrogen atoms under precisely identical laboratory conditions. Due to the high density of states in the parameter regime typically explored in laboratory experiments, such simulations are only possible with the most advanced parallel computing facilities, in combination with an efficient parallel implementation of the numerical approach. The second part of the thesis is devoted to the results of the numerical experiment. We identify and describe significant differences and surprising similarities in the ionization dynamics of atomic hydrogen as compared to alkali atoms, and give account of the relevant frequency scales that distinguish hydrogenic from non-hydrogenic ionization behavior. Our results necessitate a reinterpretation of the experimental results so far available, and solve the puzzle of a distinct ionization behavior of periodically driven hydrogen and non-hydrogenic Rydberg atoms - an unresolved question for about one decade. Finally, microwave-driven Rydberg states will be considered as prototypes of open, complex quantum systems that exhibit a complicated temporal decay

  6. Winter Weather: Frostbite

    Science.gov (United States)

    ... Safety During Fire Cleanup Wildfires PSAs Related Links Winter Weather About Winter Weather Before a Storm Prepare Your Home Prepare Your Car Winter Weather Checklists During a Storm Indoor Safety During ...

  7. Davos-Laret Remote Sensing Field Laboratory: 2016/2017 Winter Season L-Band Measurements Data-Processing and Analysis

    Directory of Open Access Journals (Sweden)

    Reza Naderpour

    2017-11-01

    Full Text Available The L-band radiometry data and in-situ ground and snow measurements performed during the 2016/2017 winter campaign at the Davos-Laret remote sensing field laboratory are presented and discussed. An improved version of the procedure for the computation of L-band brightness temperatures from ELBARA radiometer raw data is introduced. This procedure includes a thorough explanation of the calibration and filtering including a refined radio frequency interference (RFI mitigation approach. This new mitigation approach not only performs better than conventional “normality” tests (kurtosis and skewness but also allows for the quantification of measurement uncertainty introduced by non-thermal noise contributions. The brightness temperatures of natural snow covered areas and areas with a reflector beneath the snow are simulated for varying amounts of snow liquid water content distributed across the snow profile. Both measured and simulated brightness temperatures emanating from natural snow covered areas and areas with a reflector beneath the snow reveal noticeable sensitivity with respect to snow liquid water. This indicates the possibility of estimating snow liquid water using L-band radiometry. It is also shown that distinct daily increases in brightness temperatures measured over the areas with the reflector placed on the ground indicate the onset of the snow melting season, also known as “early-spring snow”.

  8. Identifying Discrimination at Work: The Use of Field Experiments.

    Science.gov (United States)

    Pager, Devah; Western, Bruce

    2012-06-01

    Antidiscrimination law offers protection to workers who have been treated unfairly on the basis of their race, gender, religion, or national origin. In order for these protections to be invoked, however, potential plaintiffs must be aware of and able to document discriminatory treatment. Given the subtlety of contemporary forms of discrimination, it is often difficult to identify discrimination when it has taken place. The methodology of field experiments offers one approach to measuring and detecting hiring discrimination, providing direct observation of discrimination in real-world settings. In this article, we discuss the findings of two recent field experiments measuring racial discrimination in low wage labor markets. This research provides several relevant findings for researchers and those interested in civil rights enforcement: (1) it produces estimates of the rate of discrimination at the point of hire; (2) it yields evidence about the interactions associated with discrimination (many of which reveal the subtlety with which contemporary discrimination is practiced); and (3) it provides a vehicle for both research on and enforcement of antidiscrimination law.

  9. Multi-Disciplinary Research Experiences Integrated with Industry –Field Experiences

    Directory of Open Access Journals (Sweden)

    Suzanne Lunsford

    2015-10-01

    Full Text Available The purpose of this environmentally inquiry-based lab was to allow the students to engage into real-world concepts that integrate industry setting (Ohio Aggregate Industrial Mineral Association with the academia setting. Our students are engaged into a field trip where mining occurs to start the problem based learning of how the heavy metals leak in the mining process. These heavy metals such as lead and indium in the groundwater are a serious concern for the environment (Environmental Protection Agency from the mining process. The field experiences at the mining process assist in building our students interest in developing sensors to detect heavy metals of concern such as lead and indium simultaneously by a unique electrochemistry technique called Square Wave Anodic Stripping Voltammetry (SWASV. The field experience assists building the students interest in real –world application and what qualities do they want the electrochemical sensor to possess to be successful for real world usage. During the field trip the students are engaged into learning novel instrumentation such as an SEM (Scanning Electron Microscope to study the working electrode sensor developed to understand the sensor surface morphology properties better as well. The integration of industry setting with academia has been a positive experience for our students that has allowed their understanding of real-world science research needs to succeed in an industrial setting of research.

  10. Transverse dispersion: From laboratory experiments to field applications

    Science.gov (United States)

    Grathwohl, Peter; Rügner, Hermann

    2016-04-01

    Transverse dispersion is relevant for dilution of contaminant plumes in groundwater and in many cases controls the length of steady state plumes during natural attenuation. Also dissolution kinetics of NAPLs in porous media and mass transfer of vapor phase compounds across the capillary fringe (e.g. supply of oxygen) is limited by transverse dispersion. In bench scale laboratory experiments typically very small dispersion coefficients are observed. Transverse dispersivities determined in DNAPL pool dissolution experiments in coarse sands are less than 0.1 mm which agrees with results from lab experiments on dilution of tracers and transfer of oxygen across the capillary fringe. Such low dispersivities lead to long-term persistence of DNAPL pools of many decades to centuries which is confirmed e.g. for chlorinated solvents and coal tars by observations at contaminated sites. However, larger scale investigations, e.g. determination of the length of steady state plumes or reduction of mass fluxes of biodegradable compounds suggest that transverse dispersivities at field scale are up to 3 orders of magnitude higher (1 -10 cm). Reasons for this discrepancy are still unclear, but may be partly explained by processes enhancing transverse mixing such as flow focusing due to aquifer geometries or high permeability inclusions and helical groundwater flow induced by herringbone structures in sediments.

  11. Field experiments using SPEAR: a speech control system for UGVs

    Science.gov (United States)

    Chhatpar, Siddharth R.; Blanco, Chris; Czerniak, Jeffrey; Hoffman, Orin; Juneja, Amit; Pruthi, Tarun; Liu, Dongqing; Karlsen, Robert; Brown, Jonathan

    2009-05-01

    This paper reports on a Field Experiment carried out by the Human Research and Engineering Directorate at Ft. Benning to evaluate the efficacy of using speech to control an Unmanned Ground Vehicle (UGV) concurrently with a handcontroller. The SPEAR system, developed by Think-A-Move, provides speech-control of UGVs. The system picks up user-speech in the ear canal with an in-ear microphone. This property allows it to work efficiently in high-noise environments, where traditional speech systems, employing external microphones, fail. It has been integrated with an iRobot PackBot 510 with EOD kit. The integrated system allows the hand-controller to be supplemented with speech for concurrent control. At Ft. Benning, the integrated system was tested by soldiers from the Officer Candidate School. The Experiment had dual focus: 1) Quantitative measurement of the time taken to complete each station and the cognitive load on users; 2) Qualitative evaluation of ease-of-use and ergonomics through soldier-feedback. Also of significant benefit to Think-A-Move was soldier-feedback on the speech-command vocabulary employed: What spoken commands are intuitive, and how the commands should be executed, e.g., limited-motion vs. unlimited-motion commands. Overall results from the Experiment are reported in the paper.

  12. Toroidal magnetic field system for 2-MA reversed-field pinch experiment

    Science.gov (United States)

    Melton, J. G.; Linton, T. W.

    The engineering design of the toroidal magnetic field (TF) system for a 2-MA Reversed Field Pinch experiment (ZT-H) is described. ZT-H is designed with major radius 2.15 meters, minor radius 0.40 meters, and a peak toroidal magnetic field of 0.85 Tesla. The requirement for highly uniform fields, with spatial ripple 0.2% leads to a design with 72 equally spaced circular TF coils, located at minor radius 0.6 meters, carrying a maximum current of 9.0 MA. The coils are driven by a 12-MJ capacitor bank which is allowed to ring in order to aid the reversal of magnetic field. A stress analysis is presented, based upon calculated loop tension, centering force, and overturning moment, treating these as a combination of static loads and considering that the periodic nature of the loading causes little amplification. The load transfer of forces and moments is considered as a stress distribution resisted by the coils, support structures, wedges, and the structural shell.

  13. Winter active bumblebees (Bombus terrestris achieve high foraging rates in urban Britain.

    Directory of Open Access Journals (Sweden)

    Ralph J Stelzer

    2010-03-01

    Full Text Available Foraging bumblebees are normally associated with spring and summer in northern Europe. However, there have been sightings of the bumblebee Bombus terrestris during the warmer winters in recent years in southern England. But what floral resources are they relying upon during winter and how much winter forage can they collect?To test if urban areas in the UK provide a rich foraging niche for bees we set up colonies of B. terrestris in the field during two late winter periods (2005/6 & 2006/7 in London, UK, and measured their foraging performance. Fully automatic radio-frequency identification (RFID technology was used in 2006/7 to enable us to record the complete foraging activity of individually tagged bees. The number of bumblebees present during winter (October 2007 to March 2008 and the main plants they visited were also recorded during transect walks. Queens and workers were observed throughout the winter, suggesting a second generation of bee colonies active during the winter months. Mass flowering shrubs such as Mahonia spp. were identified as important food resources. The foraging experiments showed that bees active during the winter can attain nectar and pollen foraging rates that match, and even surpass, those recorded during summer.B. terrestris in the UK are now able to utilise a rich winter foraging resource in urban parks and gardens that might at present still be under-exploited, opening up the possibility of further changes in pollinator phenology.

  14. Winter Chickadees

    Science.gov (United States)

    Sarvis, Gisele Winton

    2010-01-01

    Hiking between the farmer's field and the deciduous forest at Scanlon Creek Nature Centre near Bradford, Ontario, a grade 3 class and the author were studying different types of soils. As soil explorers they were hiking to different locations to see, touch and smell clay, silt and humus soils. The author always likes to bring a sense of discovery…

  15. Fate of diuron and linuron in a field lysimeter experiment.

    Science.gov (United States)

    Guzzella, L; Capri, E; Di Corcia, A; Barra Caracciolo, A; Giuliano, G

    2006-01-01

    The environmental fate of herbicides can be studied at different levels: in the lab with disturbed or undisturbed soil columns or in the field with suction cup lysimeters or soil enclosure lysimeters. A field lysimeter experiment with 10 soil enclosures was performed to evaluate the mass balance in different environmental compartments of the phenylurea herbicides diuron [3-(3,4-diclorophenyl)-1,1-dimethyl-urea] and linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea]. After application on the agricultural soil, the herbicides were searched for in soil, pore water, and air samples. Soil and water samples were collected at different depths of the soil profile and analyzed to determine residual concentrations of both the parent compounds and of their main transformation products, to verify their persistence and their leaching capacity. Air volatilization was calculated using the theoretical profile shape method. The herbicides were detected only in the surface layer (0-10 cm) of soil. In this layer, diuron was reduced to 50% of its initial concentration at the end of the experiment, while linuron was still 70% present after 245 d. The main metabolites detected were DCPMU [3-(3,4-dichlorophenyl)-1-methylurea] and DCA (3,4-dichloroaniline). In soil pore water, diuron and linuron were detected at depths of 20 and 40 cm, although in very low concentrations. Therefore the leaching of these herbicides was quite low in this experiment. Moreover, volatilization losses were inconsequential. The calculated total mass balance showed a high persistence of linuron and diuron in the soil, a low mobility in soil pore water (less than 0.5% in leachate water), and a negligible volatilization effect. The application of the Pesticide Leaching Model (PELMO) showed similar low mobility of the chemicals in soil and water, but overestimated their volatilization and their degradation to the metabolite DCPMU. In conclusion, the use of soil enclosure lysimeters proved to be a good

  16. Learning through a Winter's Tale

    Science.gov (United States)

    Vidotto, Kristie

    2010-01-01

    In this article, the author shares her experience during the final semester of Year 11 Theatre Studies when she performed a monologue about Hermione from "The Winter's Tale". This experience was extremely significant to her because it nearly made her lose faith in one of the most important parts of her life, drama. She believes this…

  17. Microwave Remote Sensing and the Cold Land Processes Field Experiment

    Science.gov (United States)

    Kim, Edward J.; Cline, Don; Davis, Bert; Hildebrand, Peter H. (Technical Monitor)

    2001-01-01

    The Cold Land Processes Field Experiment (CLPX) has been designed to advance our understanding of the terrestrial cryosphere. Developing a more complete understanding of fluxes, storage, and transformations of water and energy in cold land areas is a critical focus of the NASA Earth Science Enterprise Research Strategy, the NASA Global Water and Energy Cycle (GWEC) Initiative, the Global Energy and Water Cycle Experiment (GEWEX), and the GEWEX Americas Prediction Project (GAPP). The movement of water and energy through cold regions in turn plays a large role in ecological activity and biogeochemical cycles. Quantitative understanding of cold land processes over large areas will require synergistic advancements in 1) understanding how cold land processes, most comprehensively understood at local or hillslope scales, extend to larger scales, 2) improved representation of cold land processes in coupled and uncoupled land-surface models, and 3) a breakthrough in large-scale observation of hydrologic properties, including snow characteristics, soil moisture, the extent of frozen soils, and the transition between frozen and thawed soil conditions. The CLPX Plan has been developed through the efforts of over 60 interested scientists that have participated in the NASA Cold Land Processes Working Group (CLPWG). This group is charged with the task of assessing, planning and implementing the required background science, technology, and application infrastructure to support successful land surface hydrology remote sensing space missions. A major product of the experiment will be a comprehensive, legacy data set that will energize many aspects of cold land processes research. The CLPX will focus on developing the quantitative understanding, models, and measurements necessary to extend our local-scale understanding of water fluxes, storage, and transformations to regional and global scales. The experiment will particularly emphasize developing a strong synergism between process

  18. From Perceptual Apparatus to Immersive Field of Experience

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2014-01-01

    Peter Sloterdijk ascribes to architecture the “the design of immersions” and hence the “production of embedding situations” or atmosphere (2011 (2006): 108-109), which as devised by Gernot Böhme becomes a fundamental concept of a new aesthetics (1993). Atmosphere implies affective immersion and a....... Engels-Schwarzpaul, Trans.). In Interstices. Journal of Architecture and Related Arts. Unsettled Containers: Aspects of Interiority, 12, pp. 105-109......Peter Sloterdijk ascribes to architecture the “the design of immersions” and hence the “production of embedding situations” or atmosphere (2011 (2006): 108-109), which as devised by Gernot Böhme becomes a fundamental concept of a new aesthetics (1993). Atmosphere implies affective immersion...... the immersive experiences relocate the vision within a “carnal density” (1992: 150), regaining all sensory modalities. Diverse perceptual apparatuses also defined a larger disciplinary expansion in the field of architecture and design. Conceived as sensorial activators, intensifiers of phenomena...

  19. Contributions of meaningful experiences gatherings to artistic education field

    Directory of Open Access Journals (Sweden)

    Bernardo Bustamante Cardona

    2012-06-01

    Full Text Available This article shows a theoretical approach to and a description of some contributions of a work of transformation of educational and sociocultural reality carried out by a group of people and institutions, among which are San Buenaventura University, Antioquia Museum, Ediarte Inc. and Antioquia University. Such intervention aims at contributing to the improvement of Artistic Education quality in Antioquia and the nation. In order to understand the significance of these Gatherings, a short historical framework is explained in which global and regional processes of academic activities having an impact on the structure of the Artistic Education field are pointed out. Likewise, some perspectives in the definition of artistic education are tackled and then a definition of Pierre Bourdieu´s concept of fieldis presented. Therefore, Meaningful Experiences Gatherings in Artistic Education (MEGAE are presented and the three first gatherings are described. Finally, it is shown the panorama of the contributions of the gatherings both in the theoretical formulation and relational structure of the field.

  20. ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Leung, L Ruby [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-03-01

    The U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility’s ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) field campaign contributes to CalWater 2015, a multi-agency field campaign that aims to improve understanding of atmospheric rivers and aerosol sources and transport that influence cloud and precipitation processes. The ultimate goal is to reduce uncertainties in weather predictions and climate projections of droughts and floods in California. With the DOE G-1 aircraft and ARM Mobile Facility 2 (AMF2) well equipped for making aerosol and cloud measurements, ACAPEX focuses specifically on understanding how aerosols from local pollution and long-range transport affect the amount and phase of precipitation associated with atmospheric rivers. ACAPEX took place between January 12, 2015 and March 8, 2015 as part of CalWater 2015, which included four aircraft (DOE G-1, National Oceanic and Atmospheric Administration [NOAA] G-IV and P-3, and National Aeronautics and Space Administration [NASA] ER-2), the NOAA research ship Ron Brown, carrying onboard the AMF2, National Science Foundation (NSF)-sponsored aerosol and precipitation measurements at Bodega Bay, and the California Department of Water Resources extreme precipitation network.

  1. Design experiences for medical irradiation field at the musashi reactor

    International Nuclear Information System (INIS)

    Aizawa, Otohiko

    1994-01-01

    The design of the medical irradiation field at the Musashi reactor was carried out from 1974 to 1975, about 20 years ago. Various numerical analyses have been carried out recently, and it is astonishing to find out that the performance close to the optimum as a 100 kW reactor has been obtained. The reason for this is that the design was carried out by dividing into the stationary part and the moving part, and as for the moving part, the structure was determined by repeating trial and error and experiments. In this paper, the comparison of the analysis carried out later with the experimental data and the change of the absorbed dose at the time of medical irradiation accompanying the change of neutron energy spectra are reported. As the characteristics of the medical irradiation field at the Musashi reactor, the neutron energy spectra and the absorbed dose and mean medical irradiation time are shown. As the problems in boron neutron capture therapy, the neutron fluence required for the therapy, the way of thinking on background dose, and the problem of determining the irradiation time are discussed. The features of epithermal neutron beam are explained. (K.I.)

  2. [Effects of irrigation time on the growth and water- and fertilizer use efficiencies of winter wheat].

    Science.gov (United States)

    Dang, Jian-You; Pei, Xue-Xia; Wang, Jiao-Ai; Zhang, Jing; Cao, Yong; Zhang, Ding-Yi

    2012-10-01

    A field experiment was conducted to study the effects of irrigation time before wintering (November 10th, November 25th, and December 10th) and in spring (March 5th, re-greening stage; and April 5th, jointing stage) on the growth, dry matter translocation, water use efficiency (WUE), and fertilizer use efficiency (FUE) of winter wheat after returning corn straw into soil. The irrigation time before wintering mainly affected the wheat population size before wintering and at jointing stage, whereas the irrigation time in spring mainly affected the spike number, grain yield, dry matter translocation, WUE, and FUE. The effects of irrigation time before wintering to the yield formation of winter wheat were closely related to the irrigation time in spring. When the irrigation time in spring was at re-greening stage, the earlier the irrigation time before wintering, the larger the spike number and the higher the grain yield; when the irrigation time in spring was at jointing stage, the delay of the irrigation time before wintering made the spike number and grain yield decreased after an initial increase, the kernel number per plant increased, while the 1000-kernel mass was less affected. The WUE, nutrition uptake, and FUE all decreased with the delay of the irrigation time before wintering, but increased with the delay of the irrigation time in spring. Therefore, under the conditions of returning corn straw into soil and sowing when the soil had enough moisture, to properly advance the irrigation time before wintering could make the soil more compacted, promote the tillering and increase the population size before winter, and in combining the increased irrigation at jointing stage, could control the invalid tillering in early spring, increase the spiking rate, obtain stable kernel mass, and thus, increase the WUE and FUE, realizing water-saving and high efficiency for winter wheat cultivation.

  3. Decontamination and winter conditions

    International Nuclear Information System (INIS)

    Quenild, C.; Tveten, U.

    1984-12-01

    The report deals with two decontamonation experiments under winter conditions. A snow-covered parking lot was contaminated, and the snow was subsequently removed using standard snow-moving equipment. The snow left behind was collected and the content of contaminant was determined. A non-radioactive contaminant was used. A decontamination factor exceeding 100 was obtained. Although the eksperimental conditions were close to ideal, it is reason to believe that extremely efficient removal of deposited materials on a snow surface is achivable. In another investigation, run-off from agricultural surface, contaminated while covered with snow, was measured A lycimeter was used in this experiment. A stable layer of ice and snow was allowed to form before contamination. The run-off water was collected at each thaw period until all snow and ice was gone. Cs-134 was used as contaminant. Roughly 30% of the Cs-134 with which the area was contaminated ran off with the melt water. Following a reactor accident situation, this would have given a corresponding reduction in the long term doses. Both of these experiments show that consequence calculation assumptions, as they are currently applied to large accident assessment, tend to overestimate the consequences resulting from accidents taking place under winter conditions

  4. Summer and winter time heterogeneity in aerosol single scattering albedo over the northwestern Atlantic Ocean during the TCAP field campaign: Relationship to chemical composition and mixing state

    Science.gov (United States)

    Berg, L. K.; Chand, D.; Fast, J. D.; Zelenyuk, A.; Wilson, J. M.; Sedlacek, A. J., III; Tomlinson, J. M.; Hubbe, J. M.; Comstock, J. M.; Mei, F.; Kassianov, E.; Schmid, B.

    2015-12-01

    Aerosol play crucial role in earth's radiative budget by scattering and absorbing solar radiation. The impact of aerosol on radiation budget depend on several factors including single scattering albedo (SSA), composition, and the growth processes, like coating or mixing. We describe findings relevant to optical properties of aerosol characterized over the Cape Cod and nearby northwest Atlantic Ocean during the Two Column Aerosol Project (TCAP) during the summer (July 2012) and winter (February 2013) campaigns. The average single scattering albedo (SSA) shows distinctly different vertical profiles during the summer and winter periods. During the summer study period, the average SSA is greater than 0.95 near surface, it increases to 0.97 until an altitude of 2.5 km, and then decreases to 0.94 at top of the column near 4 km. In contrast, during the winter study period the average SSA is less than 0.93 and decreases with height reaching an average value of 0.87 near the top of the column. The large difference in summer and winter time SSA is linked to the presence of biomass burning (BB) aerosol rather than black carbon or soot in both seasons. In our study, the BB on average is factor of two higher in free troposphere (FT) during summer and more than a factor of two higher in the boundary layer during winter. Single particle analysis indicates that the average profiles of refractory black carbon (rBC) mass are similar in both seasons. The average rBC size are similar at all altitudes sampled (0-4 km) in summer time but different during winter time. In addition, the particles sampled in the summertime FT appear to be more aged than those seen during winter. The observed large heterogeneity in SSA and its links to the particle coating and composition highlights the importance of aging and mixing processes of aerosol in this region and represents a challenge for both regional and global scale models.

  5. An Oceanographic Decision Support System for Scientific Field Experiments

    Science.gov (United States)

    Maughan, T.; Das, J.; McCann, M. P.; Rajan, K.

    2011-12-01

    Thom Maughan, Jnaneshwar Das, Mike McCann, Danelle Cline, Mike Godin, Fred Bahr, Kevin Gomes, Tom O'Reilly, Frederic Py, Monique Messie, John Ryan, Francisco Chavez, Jim Bellingham, Maria Fox, Kanna Rajan Monterey Bay Aquarium Research Institute Moss Lading, California, United States Many of the coastal ocean processes we wish to observe in order to characterize marine ecosystems have large spatial extant (tens of square km) and are dynamic moving kilometers in a day with biological processes spanning anywhere from minutes to days. Some like harmful algal blooms generate toxins which can significantly impact human health and coastal economies. In order to obtain a viable understanding of the biogeochemical processes which define their dynamics and ecology, it is necessary to persistently observe, track and sample within and near the dynamic fields using augmented methods of observation such as autonomous platforms like AUVs, gliders and surface craft. Field experiments to plan, execute and manage such multitude of assets are challenging. To alleviate this problem the autonomous systems group with its collaborators at MBARI and USC designed, built and fielded a prototype Oceanographic Decision Support System (ODSS) that provides situational awareness and a single portal to visualize and plan deployments for the large scale October 2010 CANON field program as well as a series of 2 week field programs in 2011. The field programs were conducted in Monterey Bay, a known 'red tide' incubator, and varied from as many as twenty autonomous platforms, four ships and 2 manned airplanes to coordinated AUV operations, drifters and a single ship. The ODSS web-based portal was used to assimilate information from a collection of sources at sea, including AUVs, moorings, radar data as well as remote sensing products generated by partner organizations to provide a synthesis of views useful to predict the movement of a chlorophyll patch in the confines of the northern Monterey Bay

  6. A Field Experiment on Enhancement of Crop Yield by Rice Straw and Corn Stalk-Derived Biochar in Northern China

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2015-10-01

    Full Text Available Biochar, a green way to deal with burning and burying biomass, has attracted more attention in recent years. To fill the gap of the effects of different biochar on crop yield in Northern China, the first field experiment was conducted in farmland located in Hebei Province. Biochars derived from two kinds of feedstocks (rice straw and corn stalk were added into an Inceptisols area with different dosages (1 ton/ha, 2 ton/ha or 4 ton/ha in April 2014. The crop yields were collected for corn, peanut, and sweet potato during one crop season from spring to autumn 2014, and the wheat from winter 2014 to summer 2015, respectively. The results showed biochar amendment could enhance yields, and biochar from rice straw showed a more positive effect on the yield of corn, peanut, and winter wheat than corn stalk biochar. The dosage of biochar of 2 ton/ha or 1 ton/ha could enhance the yield by 5%–15% and biochar of 4 ton/ha could increase the yield by about 20%. The properties of N/P/K, CEC, and pH of soils amended with biochar were not changed, while biochar effects could be related to improvement of soil water content.

  7. Status of SRNL radiological field lysimeter experiment-Year 1

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Roberts, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Bagwell, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2013-10-01

    The Savannah River National Laboratory (SRNL) Radiological Field Lysimeter Experiment is a one-of-a-kind field facility designed to study radionuclide geochemical processes at a larger spatial scale (from grams to tens of kilograms sediment) and temporal scale (from months to 10 years) than is readily afforded through laboratory studies. The lysimeter facility is intended to capture the natural heterogeneity of moisture and temperature regimes in the vadose zone, the unsaturated subsurface region between the surface soil and the underlying aquifer. The 48 lysimeter columns, which contain various radionuclides (and stable iodine), were opened to rainfall infiltration on July 5, 2012. The objective of this report is to provide a status of the lysimeter facility operations and to compile data collected during FY13, including leachate volume, rainfall, and soil moisture and temperature in situ probe data. Radiological leachate data are not presented in this document but will be the subject of a separate document.1 Leachate samples were collected quarterly and shipped to Clemson University for radiological analyses. Rainfall, leachate volume, moisture and temperature probe data were collected continuously. During operations of the facility this year, there were four safety or technical concerns that required additional maintenance: 1) radioactivity was detected in one of the overflow bottles (captured water collected from the secondary containment that does not come in contact with the radiological source material); 2) rainwater accumulated within the sample-bottle storage sheds; 3) overflow containers collected more liquid than anticipated; and 4) significant spider infestation occurred in the sample-bottle storage sheds. To address the first three concerns, each of the lysimeter columns was re-plumbed to improve and to minimize the number of joint unions. To address the fourth concern regarding spiders, new sample-bottle water sheds were purchased and a pest control

  8. Geothermal injection treatment: process chemistry, field experiences, and design options

    Energy Technology Data Exchange (ETDEWEB)

    Kindle, C.H.; Mercer, B.W.; Elmore, R.P.; Blair, S.C.; Myers, D.A.

    1984-09-01

    The successful development of geothermal reservoirs to generate electric power will require the injection disposal of approximately 700,000 gal/h (2.6 x 10/sup 6/ 1/h) of heat-depleted brine for every 50,000 kW of generating capacity. To maintain injectability, the spent brine must be compatible with the receiving formation. The factors that influence this brine/formation compatibility and tests to quantify them are discussed in this report. Some form of treatment will be necessary prior to injection for most situations; the process chemistry involved to avoid and/or accelerate the formation of precipitate particles is also discussed. The treatment processes, either avoidance or controlled precipitation approaches, are described in terms of their principles and demonstrated applications in the geothermal field and, when such experience is limited, in other industrial use. Monitoring techniques for tracking particulate growth, the effect of process parameters on corrosion and well injectability are presented. Examples of brine injection, preinjection treatment, and recovery from injectivity loss are examined and related to the aspects listed above.

  9. Bio-mechanical removing of contaminated soils: a field experiment

    International Nuclear Information System (INIS)

    Jouve, A.; Maubert, H.; Schulte, E.

    1992-01-01

    If, in spite of safety precautions, a major nuclear accident would occur, countermeasures should be taken to attenuate the impact of radioactive deposits. The European RESSAC program (REhabilitation of Soils and Surfaces after an ACcident) aims at studying actions for normal life return in contaminated zones. One of them, called the Decontaminating Vegetal Network (D.V.N.) associates the biological action of turfing plants, producing a dense root-network capable to trap the top contaminated soil particles, and the mechanical efficiency of a turf harvester which can remove only 1 cm of soil. This performance, not associated with other techniques of soil removal such as scrapers or bulldozers, leads to minimize the waste production. The D.V.N is a vegetal cover spread over the contaminated soil, using the hydro-seeding technique. The growing plants are forming a pleasant lawn which may have a positive impact on the public opinion compared to techniques using bitumen mixtures to cover the soil. Field experiments involving labelling solutions of stable molybdenum salts simulating the contamination of the soil have shown that this technique can be applied as well on homogeneous cultivated soil surfaces as on roughly ploughed soils. 4 refs., 3 figs., 2 tabs

  10. Idaho field experiment 1981. Volume 2: measurement data

    Energy Technology Data Exchange (ETDEWEB)

    Start, G E; Sagendorf, J F; Ackermann, G R; Cate, J H; Hukari, N F; Dickson, C R

    1984-04-01

    The 1981 Idaho Field Experiment was conducted in southeastern Idaho over the upper Snake River Plain. Nine test-day case studies were conducted between July 15 and 30, 1981. Releases of SF/sub 6/ gaseous tracer were made for 8-hour periods from 46m above ground. Tracer was sampled hourly, for 12 sequential hours, at about 100 locations within an area 24km square. Also, a single total integrated sample of about 30 hours duration was collected at approximately 100 sites within an area 48 by 72km square (using 6km spacings). Extensive tower profiles of meteorology at the release point were collected. RAWINSONDES, RABALS and PIBALS were collected at 3 to 5 sites. Horizontal, low-altitude winds were monitored using the INEL MESONET. SF/sub 6/ tracer plume releases were marked with co-located oil fog releases and bi-hourly sequential launches of tetroon pairs. Aerial LIDAR observations of the oil fog plume and airborne samples of SF/sub 6/ were collected. High altitude aerial photographs of daytime plumes were collected. Volume II lists the data in tabular form or cites the special supplemental reports by other participating contractors. While the primary user file and the data archive are maintained on 9 track/1600 cpi magnetic tapes, listings of the individual values are provided for the user who either cannot utilize the tapes or wishes to preview the data. The accuracies and quality of these data are described.

  11. ARM West Antarctic Radiation Experiment (AWARE) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Lubin, Daniel [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography; Bromwich, David H [Ohio State University; Vogelmann, Andrew M [Brookhaven National Lab. (BNL), Upton, NY (United States); Verlinde, Johannes [Pennsylvania State Univ., University Park, PA (United States); Russell, Lynn M [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography

    2017-09-15

    The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment (AWARE) is the most technologically advanced atmospheric and climate science campaign yet fielded in Antarctica. AWARE was motivated be recent concern about the impact of cryospheric mass loss on global sea level rise. Specifically, the West Antarctic Ice Sheet (WAIS) is now the second largest contributor to rising sea level, after the Greenland Ice Sheet. As steadily warming ocean water erodes the grounding lines of WAIS components where they meet the Amundsen and Bellingshausen Seas, the retreating grounding lines moving inland and downslope on the underlying terrain imply mechanical instability of the entire WAIS. There is evidence that this point of instability may have already been reached, perhaps signifying more rapid loss of WAIS ice mass. At the same time, the mechanical support provided by adjacent ice shelves, and also the fundamental stability of exposed ice cliffs at the ice sheet grounding lines, will be adversely impacted by a warming atmosphere that causes more frequent episodes of surface melting. The surface meltwater damages the ice shelves and ice cliffs through hydrofracturing. With the increasing concern regarding these rapid cryospheric changes, AWARE was motivated by the need to (a) diagnose the surface energy balance in West Antarctica as related to both summer season climatology and potential surface melting, and (b) improve global climate model (GCM) performance over Antarctica, such that future cryospheric projections can be more reliable.

  12. Games for groundwater governance: field experiments in Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    Ruth Meinzen-Dick

    2016-09-01

    Full Text Available Groundwater is a common-pool resource that is subject to depletion in many places around the world as a result of increased use of irrigation and water-demanding cash crops. Where state capacity to control groundwater use is limited, collective action is important to increase recharge and restrict highly water-consumptive crops. We present results of field experiments in hard rock areas of Andhra Pradesh, India, to examine factors affecting groundwater use. Two nongovernmental organizations (NGOs ran the games in communities where they were working to improve watershed and water management. Results indicate that, when the links between crop choice and groundwater depletion is made explicit, farmers can act cooperatively to address this problem. Longer NGO involvement in the villages was associated with more cooperative outcomes in the games. Individuals with more education and higher perceived community social capital played more cooperatively, but neither gender nor method of payment had a significantly effect on individual behavior. When participants could repeat the game with communication, similar crop choice patterns were observed. The games provided an entry point for discussion on the understanding of communities of the interconnectedness of groundwater use and crop choice.

  13. Oblate Field-Reversed Configuration Experiments with Neutral Beam Injection

    Science.gov (United States)

    T., II; Gi, K.; Umezawa, T.; Inomoto, M.; Ono, Y.

    2011-11-01

    The effect of energetic beam ions on oblate Field-Reversed Configurations (FRCs) has been studied experimentally in the TS-4 plasma merging device. In order to examine its kinetic effects, we developed an economical pulsed Neutral Beam Injection (NBI) system by using a washer gun plasma source and finally attained the beam power of 0.6 MW (15 kV, 40 A) for its pulse length of 0.5 ms, longer than the FRC lifetime in TS-4. The Monte Carlo simulation indicates that the tangential NB ions of 15 keV are trapped between the magnetic axis and the separatrix. We found that two merging high-s (s is plasma size normalized by ion gyroradius) hydrogen spheromaks with opposite helicities relaxed into the large scale FRC with poloidal flux as high as 15 mWb under the assistance of the NBI. Without the assistance of NBI, however, they did not relax to an FRC but to another spheromak. These facts suggest some ion kinetic effects such as toroidal ion flow are essential to FRC stability. Recently, two new NB sources with acceleration voltage and current of 15 kV and 20 A were installed on the TS-4 device on the midplane for tangential injection, increasing the beam power over 1 MW. We will start the upgraded FRC experiments using the 1 MW NBI for ion flow control.

  14. Perspectives on global nursing leadership: international experiences from the field.

    Science.gov (United States)

    Buckner, E B; Anderson, D J; Garzon, N; Hafsteinsdóttir, T B; Lai, C K Y; Roshan, R

    2014-12-01

    Nursing leaders from six countries engaged in a year-long discussion on global leadership development. The purpose of these dialogues was to strengthen individual and collective capacity as nursing leaders in a global society. Field experiences in practice and education were shared. Perspectives on global leadership can strengthen nurses' contributions to practice, workplace and policy issues worldwide. Transformational leadership empowers nurses' increasing confidence. Mentoring is needed to stimulate leadership development but this is lacking in many settings where nurses practice, teach and influence policy. Organizations with global mission provide opportunity for nurses' professional growth in leadership through international dialogues. Dialogues among participants were held monthly by conference calls or videoconferences. Example stories from each participant illustrated nursing leadership in action. From these exemplars, concepts were chosen to create a framework. Emerging perspectives and leadership themes represented all contexts of practice, education, research and policy. The cultural context of each country was reflected in the examples. Themes emerged that crossed global regions and countries. Themes were creativity, change, collaboration, community, context and courage. Relationships initially formed in professional organizations can be extended to intentionally facilitate global nursing leadership development. Exemplars from the dialogues demonstrated nursing leadership in health policy development within each cultural context. Recommendations are given for infrastructure development in organizations to enhance future collaborations. © 2014 International Council of Nurses.

  15. Chaos in reversed-field-pinch plasma simulation and experiment

    International Nuclear Information System (INIS)

    Watts, C.; Newman, D.E.; Sprott, J.C.

    1994-01-01

    We investigate the possibility that chaos and simple determinism are governing the dynamics of reversed-field-pinch (RFP) plasmas using data from both numerical simulations and experiment. A large repertoire of nonlinear-analysis techniques is used to identify low-dimensional chaos. These tools include phase portraits and Poincare sections, correlation dimension, the spectrum of Lyapunov exponents, and short-term predictability. In addition, nonlinear-noise-reduction techniques are applied to the experimental data in an attempt to extract any underlying deterministic dynamics. Two model systems are used to simulate the plasma dynamics. These are the DEBS computer code, which models global RFP dynamics, and the dissipative trapped-electron-mode model, which models drift-wave turbulence. Data from both simulations show strong indications of low-dimensional chaos and simple determinism. Experimental data were obtained from the Madison Symmetric Torus RFP and consist of a wide array of both global and local diagnostic signals. None of the signals shows any indication of low-dimensional chaos or other simple determinism. Moreover, most of the analysis tools indicate that the experimental system is very high dimensional with properties similar to noise. Nonlinear noise reduction is unsuccessful at extracting an underlying deterministic system

  16. Improving Genomic Prediction in Cassava Field Experiments Using Spatial Analysis

    Directory of Open Access Journals (Sweden)

    Ani A. Elias

    2018-01-01

    Full Text Available Cassava (Manihot esculenta Crantz is an important staple food in sub-Saharan Africa. Breeding experiments were conducted at the International Institute of Tropical Agriculture in cassava to select elite parents. Taking into account the heterogeneity in the field while evaluating these trials can increase the accuracy in estimation of breeding values. We used an exploratory approach using the parametric spatial kernels Power, Spherical, and Gaussian to determine the best kernel for a given scenario. The spatial kernel was fit simultaneously with a genomic kernel in a genomic selection model. Predictability of these models was tested through a 10-fold cross-validation method repeated five times. The best model was chosen as the one with the lowest prediction root mean squared error compared to that of the base model having no spatial kernel. Results from our real and simulated data studies indicated that predictability can be increased by accounting for spatial variation irrespective of the heritability of the trait. In real data scenarios we observed that the accuracy can be increased by a median value of 3.4%. Through simulations, we showed that a 21% increase in accuracy can be achieved. We also found that Range (row directional spatial kernels, mostly Gaussian, explained the spatial variance in 71% of the scenarios when spatial correlation was significant.

  17. Improving Genomic Prediction in Cassava Field Experiments Using Spatial Analysis.

    Science.gov (United States)

    Elias, Ani A; Rabbi, Ismail; Kulakow, Peter; Jannink, Jean-Luc

    2018-01-04

    Cassava ( Manihot esculenta Crantz) is an important staple food in sub-Saharan Africa. Breeding experiments were conducted at the International Institute of Tropical Agriculture in cassava to select elite parents. Taking into account the heterogeneity in the field while evaluating these trials can increase the accuracy in estimation of breeding values. We used an exploratory approach using the parametric spatial kernels Power, Spherical, and Gaussian to determine the best kernel for a given scenario. The spatial kernel was fit simultaneously with a genomic kernel in a genomic selection model. Predictability of these models was tested through a 10-fold cross-validation method repeated five times. The best model was chosen as the one with the lowest prediction root mean squared error compared to that of the base model having no spatial kernel. Results from our real and simulated data studies indicated that predictability can be increased by accounting for spatial variation irrespective of the heritability of the trait. In real data scenarios we observed that the accuracy can be increased by a median value of 3.4%. Through simulations, we showed that a 21% increase in accuracy can be achieved. We also found that Range (row) directional spatial kernels, mostly Gaussian, explained the spatial variance in 71% of the scenarios when spatial correlation was significant. Copyright © 2018 Elias et al.

  18. Natural selection on immune defense: A field experiment.

    Science.gov (United States)

    Langeloh, Laura; Behrmann-Godel, Jasminca; Seppälä, Otto

    2017-02-01

    Predicting the evolution of phenotypic traits requires an understanding of natural selection on them. Despite its indispensability in the fight against parasites, selection on host immune defense has remained understudied. Theory predicts immune traits to be under stabilizing selection due to associated trade-offs with other fitness-related traits. Empirical studies, however, report mainly positive directional selection. This discrepancy could be caused by low phenotypic variation in the examined individuals and/or variation in host resource level that confounds trade-offs in empirical studies. In a field experiment where we maintained Lymnaea stagnalis snails individually in cages in a lake, we investigated phenotypic selection on two immune defense traits, phenoloxidase (PO)-like activity and antibacterial activity, in hemolymph. We used a diverse laboratory population and manipulated snail resource level by limiting their food supply. For six weeks, we followed immune activity, growth, and two fitness components, survival and fecundity of snails. We found that PO-like activity and growth were under stabilizing selection, while antibacterial activity was under positive directional selection. Selection on immune traits was mainly driven by variation in survival. The form of selection on immune defense apparently depends on the particular trait, possibly due to its importance for countering the present parasite community. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  19. EPIC Calibration/Validation Experiment Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Steven E [National Severe Storm Laboratory/NOAA; Chilson, Phillip [University of Oklahoma; Argrow, Brian [University of Colorado

    2017-03-15

    A field exercise involving several different kinds of Unmanned Aerial Systems (UAS) and supporting instrumentation systems provided by DOE/ARM and NOAA/NSSL was conducted at the ARM SGP site in Lamont, Oklahoma on 29-30 October 2016. This campaign was part of a larger National Oceanic and Atmospheric Administration (NOAA) UAS Program Office program awarded to the National Severe Storms Laboratory (NSSL). named Environmental Profiling and Initiation of Convection (EPIC). The EPIC Field Campaign (Test and Calibration/Validation) proposed to ARM was a test or “dry-run” for a follow-up campaign to be requested for spring/summer 2017. The EPIC project addresses NOAA’s objective to “evaluate options for UAS profiling of the lower atmosphere with applications for severe weather.” The project goal is to demonstrate that fixed-wing and rotary-wing small UAS have the combined potential to provide a unique observing system capable of providing detailed profiles of temperature, moisture, and winds within the atmospheric boundary layer (ABL) to help determine the potential for severe weather development. Specific project objectives are: 1) to develop small UAS capable of acquiring needed wind and thermodynamic profiles and transects of the ABL using one fixed-wing UAS operating in tandem with two different fixed rotary-wing UAS pairs; 2) adapt and test miniaturized, high-precision, and fast-response atmospheric sensors with high accuracy in strong winds characteristic of the pre-convective ABL in Oklahoma; 3) conduct targeted short-duration experiments at the ARM Southern Great Plains site in northern Oklahoma concurrently with a second site to be chosen in “real-time” from the Oklahoma Mesonet in coordination with the (National Weather Service (NWS)-Norman Forecast Office; and 4) gain valuable experience in pursuit of NOAA’s goals for determining the value of airborne, mobile observing systems for monitoring rapidly evolving high-impact severe weather

  20. Nuclear winter - a calculative experiment

    International Nuclear Information System (INIS)

    Aleksandrov, V.B.; Stenchikov, G.L.

    1985-01-01

    Using a hydrodynamic model of the Earth climate the climatic consequences following carbon dioxide concentration augmentation in the Earth atmosphere, effects of aerosol contamination and solar constant variation due to the use of nuclear weapon are studied. Results of studying the sensitivity of average annual climatic regime of the atmosphere and ocean general circulation to a sudde extremely strong, long-term change in optical properties of the air in the short-wave portion of the spectrum are discussed. These changes could be caused by contamination of the atmosphere with dust during a nuclear conflict and soot resulting from fires. It is shown, that after nuclear war according to practically any scenario, people who would survive the first blow will find themselves in conditions of a severe cold, darkness, absence of water, food and fuel under the effect of a powerful radiation, contaminants, diseases and under extreme pycological stress

  1. High magnetic field generation for laser-plasma experiments

    International Nuclear Information System (INIS)

    Pollock, B. B.; Froula, D. H.; Davis, P. F.; Ross, J. S.; Fulkerson, S.; Bower, J.; Satariano, J.; Price, D.; Krushelnick, K.; Glenzer, S. H.

    2006-01-01

    An electromagnetic solenoid was developed to study the effect of magnetic fields on electron thermal transport in laser plasmas. The solenoid, which is driven by a pulsed power system supplying 30 kJ, achieves magnetic fields of 13 T. The field strength was measured on the solenoid axis with a magnetic probe and optical Zeeman splitting. The measurements agree well with analytical estimates. A method for optimizing the solenoid design to achieve magnetic fields exceeding 20 T is presented

  2. Variation in susceptibility of field strains of three stored grain insect species to spinosad and chlorpyrifos-methyl plus deltamethrin on hard red winter wheat

    Science.gov (United States)

    Spinosad and chlorpyrifos-methyl plus deltamethrin efficacy at labeled rates on hard red winter wheat was evaluated against 11 strains of the red flour beetle, Tribolium castaneum (Herbst); six strains of the sawtoothed grain beetle, Oryzaephilus surinamensis (L.); and two strains of the lesser grai...

  3. Large-scale evaluation of pea (Pisum sativum L.) germplasm for cold tolerance in the open field during winter in Qingdao.

    Science.gov (United States)

    As a cool season crop, pea (Pisum sativum L.) can tolerate frost at the vegetative stage but has yield loss when freezing stress occurs at reproductive stage. Cold tolerance improvement of pea varieties is important for the stable yield and the expansion of winter pea planting area. Under the natura...

  4. Seed wintering and deterioration characteristics between weedy and cultivated rice

    OpenAIRE

    Baek, Jung-Sun; Chung, Nam-Jin

    2012-01-01

    Background Incidences of weedy rice continuously occurred in paddy fields because its shattering seeds were able to over-winter. In this research, the seed deterioration of weedy rice was investigated compared with cultivated rice, and the wintering characteristics of these two types of rice were investigated with the field wintering test, freezing resistance test, and accelerated aging test. Results For the wintering test, the seeds of weedy rice were placed on the soil surface of a paddy wi...

  5. Chernobyl Experience in the Field of Retrospective Dosimetry

    International Nuclear Information System (INIS)

    Chumak, V.; Bakhanova, E.

    2011-01-01

    Chernobyl accident, which occurred on April 26, 1986 at NPP located less than 150 km north of Kiev, is the largest nuclear accident ever. Unprecedented scale of the accident was determined not only by the amount of released activity, but also by a number of population and workers involved and, therefore, exposed to enhanced doses of ionizing radiation. Population of the 30-km exclusion zone numbering about 116,000 persons of all ages and both genders was evacuated within days and weeks after the accident, emergency workers called ''liquidators of the accident'' (males age 20-50) were involved into clean-up and recovery for 5 years and their number is estimated as 600,000, about 300,000 are Ukrainian citizens. Due to unexpected and excessively large scale accident, none of residents had personal dosimeters, personal dosimetry of liquidators was not total, dosimetry techniques and practices were far from the optimum. As a result, an acute need for retrospective dose assessment was dictated by radiation protection and research considerations. This need was responded by implementation of wide scale dose reconstruction efforts, which covered main exposed cohorts and encompassed broad variety of newly developed methods: analytical (time-and-motion), modeling, biological and physical (EPR spectroscopy of teeth, TL of quartz). The presentation summarizes vast experience accumulated by RCRM in the field of retrospective dosimetry of large cohorts of exposed population and professionals. These dose reconstruction projects were implemented, in particular, in the framework of epidemiological studies, designed to follow-up medical consequences of Chernobyl accident and study health effects of ionizing radiation, in particular, Ukrainian-American studies of cataracts and leukemia among liquidators. Over 25 years passed after Chernobyl accident a broad variety of retrospective dosimetry problems was addressed by the team of Research Center for Radiation Medicine AMS Ukraine. In

  6. Influence of continental advection on aerosol characteristics over Bay of Bengal (BoB in winter: results from W-ICARB cruise experiment

    Directory of Open Access Journals (Sweden)

    S. K. Kharol

    2011-08-01

    Full Text Available The transport of aerosols and pollutants from continental India to the adjoining oceanic areas is a major topic of concern and several experimental campaigns have been conducted over the region focusing on aerosol characteristics and their climate implications. The present study analyzes the spectral aerosol optical depth (AOD variations over Bay of Bengal (BoB during Winter-Integrated Campaign for Aerosols, gases and Radiation Budget (W-ICARB from 27 December 2008 to 30 January 2009 and investigates the influence of the adjoining landmass to the marine aerosol field. High AOD500 values (>0.7 occurred over northern BoB due to outflow of aerosols and pollutants from the densely populated Indo-Gangetic Plains (IGP; low AOD500 (0.1–0.2 was observed in central and southern BoB, far away from the mainland. The Angstrom exponent "α" was observed to be high (>1.2 near coastal waters, indicating relative abundance of accumulation-mode continental aerosols. On the other hand, over southern BoB its values dropped below ~0.7. National Center for Environmental Prediction (NCEP reanalysis data on winds at 850 and 700 hPa, along with air-mass trajectories calculated using Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT model, suggested transport of continental aerosols from central and northern India over the BoB. On the other hand, when the ship was crossing the eastern BoB, the aerosol loading was strongly affected by air-masses originating from Southeast Asia, causing an increase in AOD and α. Biomass-burning episodes over the region played an important role in the observed aerosol properties. Terra/Aqua Moderate Resolution Imaging Spectroradiometer (MODIS AOD550 and cruise measured AOD550 showed good agreement (R2 = 0.86 and 0.77, respectively over BoB, exhibiting similar AOD and α spatio-temporal variation.

  7. Winter School Les Houches

    CERN Document Server

    Lannoo, Michel; Bastard, Gérald; Voos, Michel; Boccara, Nino

    1986-01-01

    The Winter School held in Les Houches on March 12-21, 1985 was devoted to Semiconductor Heterojunctions and Superlattices, a topic which is recognized as being now one of the most interesting and active fields in semiconductor physics. In fact, following the pioneering work of Esaki and Tsu in 1970, the study of these two-dimensional semiconductor heterostructures has developed rapidly, both from the point of view of basic physics and of applications. For instance, modulation-doped heterojunctions are nowadays currently used to investigate the quantum Hall effect and to make very fast transistors. This book contains the lectures presented at this Winter School, showing in particular that many aspects of semiconductor heterojunctions and super­ lattices were treated, extending from the fabrication of these two-dimensional systems to their basic properties and applications in micro-and opto-electron­ ics. Among the subjects which were covered, one can quote as examples: molecular beam epitaxy and metallorgani...

  8. Winter Weather Emergencies

    Science.gov (United States)

    Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health ... Although there are no guarantees of safety during winter weather emergencies, you can take actions to protect ...

  9. Winter maintenance performance measure.

    Science.gov (United States)

    2016-01-01

    The Winter Performance Index is a method of quantifying winter storm events and the DOTs response to them. : It is a valuable tool for evaluating the States maintenance practices, performing post-storm analysis, training : maintenance personnel...

  10. Winter weather demand considerations.

    Science.gov (United States)

    2015-04-01

    Winter weather has varied effects on travel behavior. Using 418 survey responses from the Northern Virginia : commuting area of Washington, D.C. and binary logit models, this study examines travel related changes under : different types of winter wea...

  11. Using Field Experiments to Evaluate the Impact of Financial Planning and Counseling Interventions

    Science.gov (United States)

    Collins, J. Michael

    2017-01-01

    Field experiments, which are a powerful research technique, are common in some fields, but they have not been widely used in studying the effect of financial and counseling planning interventions. Financial services can benefit from the expanded use of field experiments to explore potential causal mechanisms for the effects of financial planning…

  12. Communication, Community, and Disconnection: Pre-Service Teachers in Virtual School Field Experiences

    Science.gov (United States)

    Wilkens, Christian; Eckdahl, Kelli; Morone, Mike; Cook, Vicki; Giblin, Thomas; Coon, Joshua

    2014-01-01

    This study examined the experiences of 11 graduate-level pre-service teachers completing Virtual School Field Experiences (VSFEs) with cooperating teachers in fully online, asynchronous high school courses in New York State. The VSFEs included a 7-week online teacher training course, and a 7-week online field experience. Pre-service teachers…

  13. Winter-to-winter variations in indoor radon

    International Nuclear Information System (INIS)

    Mose, D.G.; Mushrush, G.W.; Kline, S.W.

    1989-01-01

    Indoor radon concentrations in northern Virginia and central Maryland show a strong dependence on weather. Winter tends to be associated with higher than average indoor radon, and summer with lower than average. However, compared to the winter of 1986-1987, the winter of 1987-1988 was warmer and drier. Consequently, winter-to-winter indoor radon decreased by about 25%. This winter-to-winter decrease is unexpectedly large, and simulates winter-to-summer variations that have been reported

  14. Stamena winter wheat variety

    Directory of Open Access Journals (Sweden)

    Mišić Todor

    2001-01-01

    Full Text Available Stamena is a winter wheat variety developed at the Institute of Field and Vegetable Crops in Novi Sad, Yugoslavia. It was released by the Federal Commission for varietals Approval in 1999. Stamena was developed by crossing genetically divergent and highly productive parents Lasta and Rodna (Breeders: T. Mišić. N. Mladenov, Z. Jerković and R. Jevtić. Spike is white, smooth, awn less, medium compact with 18-21 spike lets. The grain is vitreous and dark red (Triticum aestivum L. ssp. vulgar e var. lutescens. Stamena is a medium early variety, 1 day earlier than Partizanka and 3 days earlier than Jugoslavija (Table 4. It has excellent resistance to winterkilling, as in very winter hardy Partizanka. The average stem height is 78 cm, with a good resistance to lodging. Stamena has field resistance to leaf rust (Pucce, recondita tritict, horizontal resistance, which is the type of resistance that modern wheat breeding is interested in. The resistance to stem rust (Pucce, graminis tritict is good and to powdery mildew (Erysiphegraminis tritici very good. The 1000 grain mass is about 32 g and volume grain mass 81.3 kg/hi. (Table 2. Stamena is classified in the subgroup A-l. It has excellent milling and baking quality and it belong to the 1st technological group (quality enhancer. The quantity of dry gluten is about 9%. The variety Stamena is a very productive, with the genetic potential for grain above 11 t/ha suitable for growing on fertile and less fertile soils. It has started to be grown commercially in 2000.

  15. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  16. Sphagnum-dwelling testate amoebae in subarctic bogs are more sensitive to soil warming in the growing season than in winter: the results of eight-year field climate manipulations.

    Science.gov (United States)

    Tsyganov, Andrey N; Aerts, Rien; Nijs, Ivan; Cornelissen, Johannes H C; Beyens, Louis

    2012-05-01

    Sphagnum-dwelling testate amoebae are widely used in paleoclimate reconstructions as a proxy for climate-induced changes in bogs. However, the sensitivity of proxies to seasonal climate components is an important issue when interpreting proxy records. Here, we studied the effects of summer warming, winter snow addition solely and winter snow addition together with spring warming on testate amoeba assemblages after eight years of experimental field climate manipulations. All manipulations were accomplished using open top chambers in a dry blanket bog located in the sub-Arctic (Abisko, Sweden). We estimated sensitivity of abundance, diversity and assemblage structure of living and empty shell assemblages of testate amoebae in the living and decaying layers of Sphagnum. Our results show that, in a sub-arctic climate, testate amoebae are more sensitive to climate changes in the growing season than in winter. Summer warming reduced species richness and shifted assemblage composition towards predominance of xerophilous species for the living and empty shell assemblages in both layers. The higher soil temperatures during the growing season also decreased abundance of empty shells in both layers hinting at a possible increase in their decomposition rates. Thus, although possible effects of climate changes on preservation of empty shells should always be taken into account, species diversity and structure of testate amoeba assemblages in dry subarctic bogs are sensitive proxies for climatic changes during the growing season. Copyright © 2011 Elsevier GmbH. All rights reserved.

  17. Population dynamics of Fusarium spp. and Microdochium nivale in crops and crop residues of winter wheat

    NARCIS (Netherlands)

    Köhl, J.; Haas, de B.H.; Kastelein, P.; Burgers, S.L.G.E.; Waalwijk, C.

    2007-01-01

    Naturally occurring populations of Fusarium avenaceum, F. culmorum, F. graminearum, F. poae, and Microdochium nivale were studied in two field experiments from anthesis in June 2003 until harvest in crops of winter wheat, and subsequently during 10 months after harvest until June 2004 on their

  18. Growth, yield and composition of four winter cereals. 1. Biomass, grain yield and yield formation.

    NARCIS (Netherlands)

    Ellen, J.

    1993-01-01

    A field experiment with 3 cultivars of each of 4 winter cereals (wheat, rye, triticale and barley), sown at about 320 plants/msuperscript 2, was conducted on a fertile clay soil in the central Netherlands. The N fertilizer was split-dressed: 120 kg/ha in total for wheat and triticale, and 60 kg/ha

  19. Nitrogen uptake, nitrate leaching and root development in winter-grown wheat and fodder radish

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Hansen, Elly Møller; Thomsen, Ingrid Kaag

    2017-01-01

    Early seeding of winter wheat (Triticum aestivum L.) has been proposed as a means to reduce N leaching as an alternative to growing cover crops like fodder radish (Raphanus sativus L.). The objective of this study was to quantify the effect of winter wheat, seeded early and normally, and of fodder...... and reduced N leaching during the winter compared with the normal seeding time. Early-seeded wheat (WWearly) was, however, not as efficient as fodder radish at reducing N leaching. Proper establishment of WWearly was a prerequisite for benefiting from early seeding, as indicated by the 2012–2013 results...... radish on N dynamics and root growth. Field experiments were carried out on a humid temperate sandy loam soil. Aboveground biomass and soil inorganic N were determined in late autumn; N uptake and grain yield of winter wheat were measured at harvest. Nitrate leaching was estimated from soil water samples...

  20. Electromagnetic fields radiated from electrostatic discharges: Theory and experiment

    Science.gov (United States)

    Wilson, Perry F.; Ondrejka, Arthur R.; Ma, Mark T.; Ladbury, John M.

    1988-02-01

    The fields radiated by electrostatic discharges (ESD) are studied both theoretically and experimentally. The ESD spark is modeled theoretically as an electrically short, time dependent, linear dipole situated above an infinite ground plane. Experimentally, sparks of varying voltages are generated by a commercially available simulator and used to excite a number of targets including: (1) the extended inner conductor of a coaxial cable mounted in a ground plane, (2) direct discharges to a ground plane, (3) indirect radiation from a large metal plate, (4) a metal chair over a a ground plane, and (5) a metal trash can. Results show that relatively low-voltage sparks (2 to 4 kV) excite the strongest radiated fields. This suggests that the spark fields can pose a significant interference threat to electronic equipment into the gigahertz range.

  1. A Comparison of Field-Based and Lab-Based Experiments to Evaluate User Experience of Personalised Mobile Devices

    Directory of Open Access Journals (Sweden)

    Xu Sun

    2013-01-01

    Full Text Available There is a growing debate in the literature regarding the tradeoffs between lab and field evaluation of mobile devices. This paper presents a comparison of field-based and lab-based experiments to evaluate user experience of personalised mobile devices at large sports events. A lab experiment is recommended when the testing focus is on the user interface and application-oriented usability related issues. However, the results suggest that a field experiment is more suitable for investigating a wider range of factors affecting the overall acceptability of the designed mobile service. Such factors include the system function and effects of actual usage contexts aspects. Where open and relaxed communication is important (e.g., where participant groups are naturally reticent to communicate, this is more readily promoted by the use of a field study.

  2. Variations in particulate matter over Indo-Gangetic Plains and Indo-Himalayan Range during four field campaigns in winter monsoon and summer monsoon: Role of pollution pathways

    Science.gov (United States)

    Sen, A.; Abdelmaksoud, A. S.; Nazeer Ahammed, Y.; Alghamdi, Mansour ِA.; Banerjee, Tirthankar; Bhat, Mudasir Ahmad; Chatterjee, A.; Choudhuri, Anil K.; Das, Trupti; Dhir, Amit; Dhyani, Pitamber Prasad; Gadi, Ranu; Ghosh, Sanjay; Kumar, Kireet; Khan, A. H.; Khoder, M.; Maharaj Kumari, K.; Kuniyal, Jagdish Chandra; Kumar, Manish; Lakhani, Anita; Mahapatra, Parth Sarathi; Naja, Manish; Pal, Dharam; Pal, S.; Rafiq, Mahammad; Romshoo, Shakil Ahmad; Rashid, Irfan; Saikia, Prasenjit; Shenoy, D. M.; Sridhar, Vijay; Verma, Nidhi; Vyas, B. M.; Saxena, Mohit; Sharma, A.; Sharma, S. K.; Mandal, T. K.

    2017-04-01

    Both in-situ and space-borne observations reveal an extremely high loading of particulates over the Indo-Gangetic Plains (IGP), all year around. With a burgeoning population and combustion sources (fossil fuels (FFs) and biofuels (BFs)) in close proximity to each other, the IGP is widely regarded as a hotspot for anthropogenic aerosol emission in South Asia. The deteriorating air quality over this region, particularly during winters, is a cause of major concern, since the pollutants undergo long range transport from their source regions to the Indo-Himalayan Range (IHR), Bay of Bengal (BoB) and other remote areas, polluting their pristine atmospheric conditions. Seasonal reversal in winds over the Indian mainland leads to an outflow of continental pollutants into the BoB during winters and a net advection of desert dust aerosols into the IGP from southwest Asia (SW-Asia), northwest India (NW-India) and northern Africa (N-Africa) during summers. Through the course of this study, four observational campaigns were conducted for sampling the ambient PM2.5 and PM10 during winter and summer seasons of 2014-2015, at multiple locations (18 sites) in the IGP, IHR, and semi-arid/arid sites towards their south and west, in order to accurately determine the inter-seasonal and inter-annual changes in the aerosol loading at the sites. We have also utilized data from Moderate Resolution Imaging Spectroradiometer (MODIS) on-board Earth Observing System (EOS) Terra satellite for estimating the columnar Aerosol Optical Depth at 550 nm (AOD550) and data from EOS Terra and Aqua satellites for discovering openly burning fires in the vicinity of sampling sites. Determination of the major source regions and key transport pathways during both seasons have also been attempted, using back-trajectory cluster analyses, as well as receptor models such as PSCF and CWT.

  3. Rocky 7 prototype Mars rover field geology experiments 1. Lavic Lake and sunshine volcanic field, California

    Science.gov (United States)

    Arvidson, R. E.; Acton, C.; Blaney, D.; Bowman, J.; Kim, S.; Klingelhofer, G.; Marshall, J.; Niebur, C.; Plescia, J.; Saunders, R.S.; Ulmer, C.T.

    1998-01-01

    Experiments with the Rocky 7 rover were performed in the Mojave Desert to better understand how to conduct rover-based, long-distance (kilometers) geological traverses on Mars. The rover was equipped with stereo imaging systems for remote sensing science and hazard avoidance and 57Fe Mo??ssbauer and nuclear magnetic resonance spectrometers for in situ determination of mineralogy of unprepared rock and soil surfaces. Laboratory data were also obtained using the spectrometers and an X ray diffraction (XRD)/XRF instrument for unprepared samples collected from the rover sites. Simulated orbital and descent image data assembled for the test sites were found to be critical for assessing the geologic setting, formulating hypotheses to be tested with rover observations, planning traverses, locating the rover, and providing a regional context for interpretation of rover-based observations. Analyses of remote sensing and in situ observations acquired by the rover confirmed inferences made from orbital and simulated descent images that the Sunshine Volcanic Field is composed of basalt flows. Rover data confirmed the idea that Lavic Lake is a recharge playa and that an alluvial fan composed of sediments with felsic compositions has prograded onto the playa. Rover-based discoveries include the inference that the basalt flows are mantled with aeolian sediment and covered with a dense pavement of varnished basalt cobbles. Results demonstrate that the combination of rover remote sensing and in situ analytical observations will significantly increase our understanding of Mars and provide key connecting links between orbital and descent data and analyses of returned samples. Copyright 1998 by the American Geophysical Union.

  4. Klaus Winter (1930 - 2015)

    CERN Multimedia

    2015-01-01

    We learned with great sadness that Klaus Winter passed away on 9 February 2015, after a long illness.   Klaus was born in 1930 in Hamburg, where he obtained his diploma in physics in 1955. From 1955 to 1958 he held a scholarship at the Collège de France, where he received his doctorate in nuclear physics under the guidance of Francis Perrin. Klaus joined CERN in 1958, where he first participated in experiments on π+ and K0 decay properties at the PS, and later became the spokesperson of the CHOV Collaboration at the ISR. Starting in 1976, his work focused on experiments with the SPS neutrino beam. In 1984 he joined Ugo Amaldi to head the CHARM experiment, designed for detailed studies of the neutral current interactions of high-energy neutrinos, which had been discovered in 1973 using the Gargamelle bubble chamber at the PS. The unique feature of the detector was its target calorimeter, which used large Carrara marble plates as an absorber material. From 1984 to 1991, Klau...

  5. Tropospheric ozone lidar intercomparison experiment, TROLIX '91, field phase report

    International Nuclear Information System (INIS)

    Boesenberg, J.; Ancellet, G.; Bergwerff, H.; Cossart, G. v.; Fiedler, J.; Jonge, C. de; Mellqvist, J.; Mitev, V.; Sonnemann, G.; Swart, D.; Wallinder, E.

    1993-01-01

    The Tropospheric Ozone Lidar Intercomparison Experiment TROLIX '91 has been initiated as part of the TESLAS subproject of the cooperative programme EUROTRAC. It has been performed in June 1991 at the Rijksinstitut voor Volksgezondheid en Milieuhygiene (RIVM) in Bilthoven, The Netherlands. The experiment was based on the simultaneous operation of different types of differential absorption lidars (DIAL), a special version of a Differential Optical Absorption Spectroscopy Instrument (DOAS), helicopter borne in situ instruments, and many other supporting measurements. After a short introduction to the general methodology the instruments are described, the experimental operations are explained, and a selection of data are presented. Some examples are given for the results of the intercomparison, as far as they have been available at the present stage of evaluation. The main purpose of this report, however, is to provide an overview over the material collected during the experiment, on order to facilitate further detailed studies in cooperation between the different groups which have participated. (orig.)

  6. Influence of oil and gas field operations on spatial and temporal distributions of atmospheric non-methane hydrocarbons and their effect on ozone formation in winter

    Science.gov (United States)

    Field, R. A.; Soltis, J.; McCarthy, M. C.; Murphy, S.; Montague, D. C.

    2015-03-01

    Emissions from oil and natural gas development during winter in the Upper Green River basin of Wyoming are known to drive episodic ozone (O3) production. Contrasting O3 distributions were observed in the winters of 2011 and 2012, with numerous episodes (hourly O3 ≥ 85 ppbv) in 2011 compared to none in 2012. The lack of O3 episodes in 2012 coincided with a reduction in measured ambient levels of total non-methane hydrocarbons (NMHC). Measurements of speciated NMHC, and other air quality parameters, were performed to better understand emission sources and to determine which compounds are most active in promoting O3 formation. Positive matrix factorization (PMF) analyses of the data were carried out to help achieve these goals. PMF analyses revealed three contributing factors that were identified with different emission source types: factor 1, combustion/traffic; factor 2, fugitive natural gas; and factor 3, fugitive condensate. Compositional signatures of the three contributing factors were identified through comparison with independently derived emission source profiles. Fugitive emissions of natural gas and of condensate were the two principal emission source types for NMHC. A water treatment and recycling facility was found to be a significant source of NMHC that are abundant in condensate, in particular toluene and m+p-xylene. Emissions from water treatment have an influence upon peak O3 mixing ratios at downwind measurement sites.

  7. The Mistra experiment for field containment code validation first results

    International Nuclear Information System (INIS)

    Caron-Charles, M.; Blumenfeld, L.

    2001-01-01

    The MISTRA facility is a large scale experiment, designed for the purpose of thermal-hydraulics multi-D codes validation. A short description of the facility, the set up of the instrumentation and the test program are presented. Then, the first experimental results, studying helium injection in the containment and their calculations are detailed. (author)

  8. Luck or cheating? A field experiment on honesty with children

    NARCIS (Netherlands)

    Bucciol, A.; Piovesan, M.

    2011-01-01

    We run an experiment to study the relationship between honesty, age and self-control. We focus on children aged between 5 and 15 as the literature suggests that self-control develops within such age range. We ask each child to toss a fair coin in private and to record the outcome (white or black) on

  9. Synoptic Meteorology during the SNOW-ONE-A Field Experiment.

    Science.gov (United States)

    1983-05-01

    experiment, and 2) summarize the locally observed surface weather reports issued during the passage of the storms*. DATA BASE The daily synoptic summaries...the electromagnetic spectrum obtained by the Geosynchronous Operational Enviromental Satellite-East (GOES-E) system*. These images were recorded at

  10. Luck or cheating? A field experiment on honesty with children

    NARCIS (Netherlands)

    Bucciol, A.; Piovesan, M.

    2008-01-01

    We ran an experiment with children to study the development of honesty with age. We asked each child to toss a fair coin in private and to record the outcome (white or black) in a paper sheet. We rewarded only those who reported white. We found a fraction of reported whites signifi cantly larger

  11. Incentives versus sorting in tournaments: evidence from a field experiment

    NARCIS (Netherlands)

    Leuven, E.; Oosterbeek, H.; Sonnemans, J.; van der Klaauw, B.

    2009-01-01

    A vast body of empirical studies lends support to the incentive effects of rankorder tournaments. Evidence comes from experiments in laboratories and non-experimental studies exploiting sports or firm data. Selection of competitors across tournaments may bias these non-experimental studies, whereas

  12. Incentives versus sorting in tournaments : evidence from a field experiment

    NARCIS (Netherlands)

    Leuven, E.; Oosterbeek, H.; Sonnemans, J.; van der Klauw, B.

    2007-01-01

    A vast body of empirical studies lends support to the incentive effects of rankorder tournaments. Direct evidence comes from experiments in laboratories or from non-experimental sports events (golf, tennis). The short duration of the tasks at hand or the lack of distractors may, however, limit the

  13. Thermal and Field Enhanced Photoemission Comparison of Theory to Experiment

    CERN Document Server

    Lynn-Jensen, Kevin

    2004-01-01

    Photocathodes are a critical component of high-gain FEL’s and the analysis of their emission is complex. Relating their performance under laboratory conditions to conditions of an rf photoinjector is difficult. Useful models must account for cathode surface conditions and material properties, as well as drive laser parameters. We have developed a time-dependent model accounting for the effects of laser heating and thermal propagation on photoemission. It accounts for surface conditions (coating, field enhancement, reflectivity), laser parameters (duration, intensity, wavelength), and material characteristics (reflectivity, laser penetration depth, scattering rates) to predict current distribution and quantum efficiency. The applicatIon will focus on photoemission from metals and, in particular, dispenser photocathodes: the later introduces complications such as coverage non-uniformity and field enhancement. The performance of experimentally characterized photocathodes will be extrapolated to 0.1 - 1 nC bunch...

  14. Fielding Army Weapon Systems: Experiences and Lessons Learned

    Science.gov (United States)

    1980-06-01

    at the highest rate we can, and the l1wer priority systems at the minimum economic rate.• I 3 Sj3 Inmortance of the Fielding Process However strong and...C OM.i1erdtJ.on neceds to be given to establishing the of- fio undiri.. the DCSLOG raithemr th’.n DCSOPS. El ffici,!-nt. fie].ding n:eq1u.1r4:,s

  15. 4D experience on Girassol Field block 17, Angola

    Energy Technology Data Exchange (ETDEWEB)

    Lefeuvre, F.; Brechet, E.; Bertini, F.; Jourdan, J.M.; Cassou, G. [TOTAL S.A., Luanda (Angola); Dubucq, D. [TOTAL Angola, Luanda (Angola)

    2004-07-01

    The Girassol field is located in Angolan deep water of Block 17 and consists of large vertically stacked turbidities complexes. The reservoir extends over approximately 200 km{sup 2} and water depth ranges between 1300 and 1400 meters. In that context High Resolution 3D seismic became the most valuable tool to describe and monitor the reservoir. The field development plan took into account, through re-injection of the gas into the reservoir, Total environmental policy imposing the recycling of production gas. Monitoring of this injection was the main reason to shoot the first High Resolution 4D extremely early in the life of field. Despite the complexity of interpretation due to complex fluid situation and pressure effect, the results went way beyond expectations as the 4D images are of very high quality. Data has also been used to update and refine the reservoir flow model as well as to help deciding on the location of latest development wells. Other repeat surveys are scheduled, the next one before the end of 2004. The ultimate goal which we hope to reach in the very near future will be to use seismic-derived saturation and pressure changes to constrain the reservoir model during the history matching process. (author)

  16. 160 Gb/s all-optical packet switching field experiment

    DEFF Research Database (Denmark)

    Dorren, H.J.S.; Herrera, J.; Raz, O.

    2007-01-01

    We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits.......We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits....

  17. The Dilemma of Field Experience Assessment: Enhancing Professional Development or Fulfilling a Gate-Keeping Function?

    Science.gov (United States)

    Cheng, May May-hung; Tang, Sylvia Yee-fan

    2008-01-01

    The field experience component in a teacher education programme serves both a gate-keeping function and a formative purpose that supports student teacher development. The authors were members of a research team which took care of the re-design of the assessment instrument for the field experience component of a teacher education programme, as well…

  18. The Influence of Technology-Rich Early Childhood Field Experiences on Preservice Teachers

    Science.gov (United States)

    Lux, Nicholas; Lux, Christine

    2015-01-01

    Despite a comprehensive body of research on field experiences in teacher education, technology-rich early field experiences in early childhood environments is one particular area of inquiry lacking substantive current research. Therefore, this study was conducted to better understand how preservice teachers' perceptions of global concepts related…

  19. Using Field Experiments to Change the Template of How We Teach Economics

    Science.gov (United States)

    List, John A.

    2014-01-01

    In this article, the author explains why field experiments can improve what we teach and how we teach economics. Economists no longer operate as passive observers of economic phenomena. Instead, they participate actively in the research process by collecting data from field experiments to investigate the economics of everyday life. This change can…

  20. Modelling the Grimsel migration field experiments at PSI

    International Nuclear Information System (INIS)

    Heer, W.

    1997-01-01

    For several years tracer migration experiments have been performed at Nagra's Grimsel Test Site as a joint undertaking of Nagra, PNC and PSI. The aims of modelling the migration experiments are (1) to better understand the nuclide transport through crystalline rock; (2) to gain information on validity of methods and correlating parameters; (3) to improve models for safety assessments. The PSI modelling results, presented here, show a consistent picture for the investigated tracers (the non-sorbing uranine, the weakly sorbing sodium, the moderately sorbing strontium and the more strongly sorbing cesium). They represent an important step in building up confidence in safety assessments for radioactive waste repositories. (author) 5 figs., 1 tab., 12 refs

  1. Gender Differences in Bargaining Outcomes: A Field Experiment on Discrimination

    OpenAIRE

    Lise Vesterlund

    2011-01-01

    We examine gender differences in bargaining outcomes in a highly competitive and commonly used market: the taxi market in Lima, Peru. Examining the entire path of negotiation we find that men face higher initial prices and rejection rates. These differentials are consistent with both statistical and taste-based discrimination. To identify the source of the inferior treatment of men we conduct an experiment where passengers send a signal on valuation before negotiating. The signal eliminates g...

  2. Measuring microbial fitness in a field reciprocal transplant experiment.

    Science.gov (United States)

    Boynton, Primrose J; Stelkens, Rike; Kowallik, Vienna; Greig, Duncan

    2017-05-01

    Microbial fitness is easy to measure in the laboratory, but difficult to measure in the field. Laboratory fitness assays make use of controlled conditions and genetically modified organisms, neither of which are available in the field. Among other applications, fitness assays can help researchers detect adaptation to different habitats or locations. We designed a competitive fitness assay to detect adaptation of Saccharomyces paradoxus isolates to the habitat they were isolated from (oak or larch leaf litter). The assay accurately measures relative fitness by tracking genotype frequency changes in the field using digital droplet PCR (DDPCR). We expected locally adapted S. paradoxus strains to increase in frequency over time when growing on the leaf litter type from which they were isolated. The DDPCR assay successfully detected fitness differences among S. paradoxus strains, but did not find a tendency for strains to be adapted to the habitat they were isolated from. Instead, we found that the natural alleles of the hexose transport gene we used to distinguish S. paradoxus strains had significant effects on fitness. The origin of a strain also affected its fitness: strains isolated from oak litter were generally fitter than strains from larch litter. Our results suggest that dispersal limitation and genetic drift shape S. paradoxus populations in the forest more than local selection does, although further research is needed to confirm this. Tracking genotype frequency changes using DDPCR is a practical and accurate microbial fitness assay for natural environments. © 2016 The Authors. Molecular Ecology Resources Published by John Wiley & Sons Ltd.

  3. Electron temperature diagnostics in the RFX reversed field pinch experiment

    International Nuclear Information System (INIS)

    Bartiromo, R.; Carraro, L.; Marrelli, L.; Murari, A.; Pasqualotto, R.; Puiatti, M.E.; Scarin, P.; Valisa, M.; Franz, P.; Martin, P.; Zabeo, L.

    2000-01-01

    The paper presents an integrated approach to the problem of electron temperature diagnostics of the plasma in a reversed field pinch. Three different methods, sampling different portions of the electron distribution function, are adopted, namely Thomson scattering, soft X-ray spectroscopy by pulse-height analysis and filtered soft X-ray intensity ratio. A careful analysis of the different sources of systematic errors is performed and a novel statistical approach is adopted to mutually validate the three independent measurements. A satisfactory agreement is obtained over a large range of experimental conditions, indicating that in the plasma core the energy distribution function is well represented by a maxwellian. (author)

  4. Determining material parameters using phase-field simulations and experiments

    DEFF Research Database (Denmark)

    Zhang, Jin; Poulsen, Stefan O.; Gibbs, John W.

    2017-01-01

    A method to determine material parameters by comparing the evolution of experimentally determined 3D microstructures to simulated 3D microstructures is proposed. The temporal evolution of a dendritic solid-liquid mixture is acquired in situ using x-ray tomography. Using a time step from these data...... as an initial condition in a phase-field simulation, the computed structure is compared to that measured experimentally at a later time. An optimization technique is used to find the material parameters that yield the best match of the simulated microstructure to the measured microstructure in a global manner...

  5. Radiation use efficiency and yield of winter wheat under deficit irrigation in North China

    International Nuclear Information System (INIS)

    Han, H.; Li, Z.; Ning, T.; Bai, M.; Zhang, X.; Shan, Y.

    2008-01-01

    An experiment was conducted in North China to investigate the effects of deficit irrigation and winter wheat varieties on the photosynthetic active radiation (PAR) capture ration, PAR utilization and grain yield. Field experiments involved Jimai 20 (J; high yield variety) and Lainong 0153 (L; dryland variety) with non-irrigation and irrigated at the jointing stage. The results showed that whether irrigated at jointing stage or not, there was no significant difference between J and L with respect to the amount of PAR intercepted by the winter wheat canopies. However, significant differences were observed between the varieties with respect to the amount of PAR intercepted by plants that were 60-80 cm above the ground surface. This result was mainly caused by the changes in the vertical distributions of leaf area index. As a result, the effects of the varieties and deficit irrigation on the radiation use efficiency (RUE) and grain yield of winter wheat were due to the vertical distribution of PAR in the winter wheat canopies. During the late growing season of winter wheat, irrespective of the irrigation regime, the RUE and grain yield of J were significantly higher than those of L. These results suggest that a combination of deficit irrigation and a suitable winter wheat variety should be applied in North China

  6. Tools and Setups for Experiments with AC and Rotating Magnetic Fields

    Science.gov (United States)

    Ponikvar, D.

    2010-01-01

    A rotating magnetic field is the basis for the transformation of electrical energy to mechanical energy. School experiments on the rotating magnetic field are rare since they require the use of specially prepared mechanical setups and/or relatively large, three-phase power supplies to achieve strong magnetic fields. This paper proposes several…

  7. Enviromental behavior of sulfentrazone and fipronil in a Brazilian clayey latosol: field experiment and simulation

    OpenAIRE

    Scorza Júnior, Rômulo Penna; Franco, André Andrade

    2014-01-01

    There has been an urgent need to assess pesticide environmental behavior under Brazilian field conditions and to evaluate the risks associated to its use in agriculture. Besides a qualitative and quantitative interpretation of field experiments to acquire understanding about pesticide environmental behaviour, field experiments are important to test pesticide fate models. Environmental behaviour of fipronil and sulfentrazone in a sugarcane area in Dourados, MS, was evaluated until 257 days aft...

  8. Norwegian Young Sea Ice Experiment (N-ICE) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Walden, V. P. [Washington State Univ., Pullman, WA (United States); Hudson, S. R. [Norwegian Polar Institute, Tromso (Norway); Cohen, L. [Norwegian Polar Institute, Tromso (Norway)

    2016-03-01

    The Norwegian Young Sea Ice (N-ICE) experiment was conducted aboard the R/V Lance research vessel from January through June 2015. The primary purpose of the experiment was to better understand thin, first-year sea ice. This includes understanding of how different components of the Arctic system affect sea ice, but also how changing sea ice affects the system. A major part of this effort is to characterize the atmospheric conditions throughout the experiment. A micropulse lidar (MPL) (S/N: 108) was deployed from the U.S. Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility as part of the atmospheric suite of instruments. The MPL operated successfully throughout the entire experiment, acquiring data from 21 January 2015 through 23 June 2015. The MPL was the essential instrument for determining the phase (water, ice or mixed) of the lower-level clouds over the sea ice. Data obtained from the MPL during the N-ICE experiment show large cloud fractions over young, thin Arctic sea ice from January through June 2015 (north of Svalbard). The winter season was characterized by frequent synoptic storms and large fluctuations in the near-surface temperature. There was much less synoptic activity in spring and summer as the near-surface temperature rose to 0 C. The cloud fraction was lower in winter (60%) than in the spring and summer (80%). Supercooled liquid clouds were observed for most of the deployment, appearing first in mid-February. Spring and summer clouds were characterized by low, thick, uniform clouds.

  9. Fusion Performance of High Magnetic Field Expe-riments

    Science.gov (United States)

    Airoldi, A.; Cenacchi, G.; Coppi, B.

    1997-11-01

    High magnetic field machines have the characteristic of operating well within the usual limitations known as density and beta limits. This feature is highlighted in the Ignitor concept thanks to its reference field of up to 13 T on the magnetic axis and its high current densities. The two reference scenarios with plasma currents of 12 MA and 11 MA respectively, are discussed. The ramp time is 4 sec for both scenarios, whereas the following programmed time dependence of the current is different. The results of an extensive series of numerical simulations using an appropriate version of the 1+1/2D JETTO transport code show that in any case optimal fusion performances are reacheable without needing enhancement over the values of the energy replacement time predicted by the most pessimistic scalings (for the so-called L-mode regime). The density is the crucial parameter involved on the path to ignition that can be achieved provided the density rise is carefully programmed. The density profiles can be controlled by the proper use of the pellet injector that is included in the machine design.

  10. Pesticide uptake in potatoes: model and field experiments.

    Science.gov (United States)

    Juraske, Ronnie; Vivas, Carmen S Mosquera; Velásquez, Alexander Erazo; Santos, Glenda García; Moreno, Mónica B Berdugo; Gomez, Jaime Diaz; Binder, Claudia R; Hellweg, Stefanie; Dallos, Jairo A Guerrero

    2011-01-15

    A dynamic model for uptake of pesticides in potatoes is presented and evaluated with measurements performed within a field trial in the region of Boyacá, Colombia. The model takes into account the time between pesticide applications and harvest, the time between harvest and consumption, the amount of spray deposition on soil surface, mobility and degradation of pesticide in soil, diffusive uptake and persistence due to crop growth and metabolism in plant material, and loss due to food processing. Food processing steps included were cleaning, washing, storing, and cooking. Pesticide concentrations were measured periodically in soil and potato samples from the beginning of tuber formation until harvest. The model was able to predict the magnitude and temporal profile of the experimentally derived pesticide concentrations well, with all measurements falling within the 90% confidence interval. The fraction of chlorpyrifos applied on the field during plant cultivation that eventually is ingested by the consumer is on average 10(-4)-10(-7), depending on the time between pesticide application and ingestion and the processing step considered.

  11. The 1987 Federal field exercise: The DOE experience

    International Nuclear Information System (INIS)

    Adler, M.V.; Gant, K.S.

    1989-06-01

    The second full-scale field exercise of the Federal Radiological Emergency Response Plan (FRERP) was held at the Zion Nuclear Power Station, Zion, Illinois, in June 1987. The exercise incorporated the annual compliance exercise for the Zion plant and involved the operating utility, Commonwealth Edison Company, the states of Illinois and Wisconsin, local governments, volunteer groups, and representatives from 12 federal agencies. The 3-day exercise was played from many locations in the Zion area; Springfield, Illinois; Madison, Wisconsin; and Washington, DC. Approximately 1000 people participated in the exercise, which used a scenario in which an accident at the plant resulted in the release of radioactive material outside the plant boundary. The US Department of Energy (DOE) had major responsibilities during the planning, playing, and critiquing of the exercise; these functions are outlined in the report. This document describes the DOE participation in the planning and response during the exercise. During a radiological emergency, the FRERP gives DOE the responsibility for coordinating the federal radiological monitoring and assessment activities in support of the states and the cognizant federal agency. At Zion, a self-sufficient Federal Radiological Monitoring and Assessment Center was established by DOE at a nearby fairground in which over 200 people from DOE, the two states, and other federal agencies participated. Before the field exercise, a tabletop exercise and a dry run were held for training purposes. 5 refs., 6 figs

  12. Mechanical weed control in organic winter wheat

    Directory of Open Access Journals (Sweden)

    Euro Pannacci

    2017-12-01

    Full Text Available Three field experiments were carried out in organic winter wheat in three consecutive years (exp. 1, 2005-06; exp. 2, 2006- 07; exp. 3, 2007-08 in central Italy (42°57’ N - 12°22’ E, 165 m a.s.l. in order to evaluate the efficacy against weeds and the effects on winter wheat of two main mechanical weed control strategies: i spring tine harrowing used at three different application times (1 passage at T1, 2 passages at the time T1, 1 passage at T1 followed by 1 passage at T1 + 14 days in the crop sowed at narrow (traditional row spacing (0.15 m; and ii split-hoeing and finger-weeder, alone and combined at T1, in the crop sowed at wider row spacing (0.30 m. At the time T1 winter wheat was at tillering and weeds were at the cotyledons-2 true leaves growth stage. The experimental design was a randomized block with four replicates. Six weeks after mechanical treatments, weed ground cover (% was rated visually using the Braun-Blanquet coverabundance scale; weeds on three squares (0.6×0.5 m each one per plot were collected, counted, weighed, dried in oven at 105°C to determine weed density and weed above-ground dry biomass. At harvest, wheat ears density, grain yield, weight of 1000 seeds and hectolitre weight were recorded. Total weed flora was quite different in the three experiments. The main weed species were: Polygonum aviculare L. (exp. 1 and 2, Fallopia convolvulus (L. Á. Löve (exp. 1 and 3, Stachys annua (L. L. (exp. 1, Anagallis arvensis L. (exp. 2, Papaver rhoeas L. (exp.3, Veronica hederifolia L. (exp. 3. In the winter wheat sowed at narrow rows, 2 passages with spring-tine harrowing at the same time seems to be the best option in order to reconcile a good efficacy with the feasibility of treatment. In wider rows spacing the best weed control was obtained by split hoeing alone or combined with finger-weeder. The grain yield, on average 10% higher in narrow rows, the lower costs and the good selectivity of spring-tine harrowing

  13. Experimental log hauling through a traditional caribou wintering area

    Directory of Open Access Journals (Sweden)

    Harold G. Cumming

    1998-03-01

    Full Text Available A 3-year field experiment (fall 1990-spring 1993 showed that woodland caribou (Rangifer tarandus caribou altered their dispersion when logs were hauled through their traditional wintering area. Unlike observations in control years 1 and 3, radio-collared caribou that had returned to the study area before the road was plowed on January 6 of the experimental year 2, moved away 8-60 km after logging activities began. Seasonal migration to Lake Nipigon islands usually peaked in April, but by February 22 of year 2, 4 of the 6 had returned. The islands provide summer refuge from predation, but not when the lake is frozen. Tracks in snow showed that some caribou remained but changed locations. They used areas near the road preferentially in year 1, early year 2, and year 3, but moved away 2-5 km after the road was plowed in year 2. In a nearby undisturbed control area, no such changes occurred. Caribou and moose partitioned habitat on a small scale; tracks showed gray wolf (Canis lupus remote from caribou but close to moose tracks. No predation on caribou was observed within the wintering area; 2 kills were found outside it. Due to the possibility of displacing caribou from winter refugia to places with higher predation risk, log hauling through important caribou winter habitat should be minimized.

  14. Influence of the mode of deformation on recrystallisation behaviour of titanium through experiments, mean field theory and phase field model

    Science.gov (United States)

    Athreya, C. N.; Mukilventhan, A.; Suwas, Satyam; Vedantam, Srikanth; Subramanya Sarma, V.

    2018-04-01

    The influence of the mode of deformation on recrystallisation behaviour of Ti was studied by experiments and modelling. Ti samples were deformed through torsion and rolling to the same equivalent strain of 0.5. The deformed samples were annealed at different temperatures for different time durations and the recrystallisation kinetics were compared. Recrystallisation is found to be faster in the rolled samples compared to the torsion deformed samples. This is attributed to the differences in stored energy and number of nuclei per unit area in the two modes of deformation. Considering decay in stored energy during recrystallisation, the grain boundary mobility was estimated through a mean field model. The activation energy for recrystallisation obtained from experiments matched with the activation energy for grain boundary migration obtained from mobility calculation. A multi-phase field model (with mobility estimated from the mean field model as a constitutive input) was used to simulate the kinetics, microstructure and texture evolution. The recrystallisation kinetics and grain size distributions obtained from experiments matched reasonably well with the phase field simulations. The recrystallisation texture predicted through phase field simulations compares well with experiments though few additional texture components are present in simulations. This is attributed to the anisotropy in grain boundary mobility, which is not accounted for in the present study.

  15. Modelling winter organic aerosol at the European scale with CAMx: evaluation and source apportionment with a VBS parameterization based on novel wood burning smog chamber experiments

    Directory of Open Access Journals (Sweden)

    G. Ciarelli

    2017-06-01

    Full Text Available We evaluated a modified VBS (volatility basis set scheme to treat biomass-burning-like organic aerosol (BBOA implemented in CAMx (Comprehensive Air Quality Model with extensions. The updated scheme was parameterized with novel wood combustion smog chamber experiments using a hybrid VBS framework which accounts for a mixture of wood burning organic aerosol precursors and their further functionalization and fragmentation in the atmosphere. The new scheme was evaluated for one of the winter EMEP intensive campaigns (February–March 2009 against aerosol mass spectrometer (AMS measurements performed at 11 sites in Europe. We found a considerable improvement for the modelled organic aerosol (OA mass compared to our previous model application with the mean fractional bias (MFB reduced from −61 to −29 %. We performed model-based source apportionment studies and compared results against positive matrix factorization (PMF analysis performed on OA AMS data. Both model and observations suggest that OA was mainly of secondary origin at almost all sites. Modelled secondary organic aerosol (SOA contributions to total OA varied from 32 to 88 % (with an average contribution of 62 % and absolute concentrations were generally under-predicted. Modelled primary hydrocarbon-like organic aerosol (HOA and primary biomass-burning-like aerosol (BBPOA fractions contributed to a lesser extent (HOA from 3 to 30 %, and BBPOA from 1 to 39 % with average contributions of 13 and 25 %, respectively. Modelled BBPOA fractions were found to represent 12 to 64 % of the total residential-heating-related OA, with increasing contributions at stations located in the northern part of the domain. Source apportionment studies were performed to assess the contribution of residential and non-residential combustion precursors to the total SOA. Non-residential combustion and road transportation sector contributed about 30–40 % to SOA formation (with increasing

  16. Modelling winter organic aerosol at the European scale with CAMx: evaluation and source apportionment with a VBS parameterization based on novel wood burning smog chamber experiments

    Science.gov (United States)

    Ciarelli, Giancarlo; Aksoyoglu, Sebnem; El Haddad, Imad; Bruns, Emily A.; Crippa, Monica; Poulain, Laurent; Äijälä, Mikko; Carbone, Samara; Freney, Evelyn; O'Dowd, Colin; Baltensperger, Urs; Prévôt, André S. H.

    2017-06-01

    We evaluated a modified VBS (volatility basis set) scheme to treat biomass-burning-like organic aerosol (BBOA) implemented in CAMx (Comprehensive Air Quality Model with extensions). The updated scheme was parameterized with novel wood combustion smog chamber experiments using a hybrid VBS framework which accounts for a mixture of wood burning organic aerosol precursors and their further functionalization and fragmentation in the atmosphere. The new scheme was evaluated for one of the winter EMEP intensive campaigns (February-March 2009) against aerosol mass spectrometer (AMS) measurements performed at 11 sites in Europe. We found a considerable improvement for the modelled organic aerosol (OA) mass compared to our previous model application with the mean fractional bias (MFB) reduced from -61 to -29 %. We performed model-based source apportionment studies and compared results against positive matrix factorization (PMF) analysis performed on OA AMS data. Both model and observations suggest that OA was mainly of secondary origin at almost all sites. Modelled secondary organic aerosol (SOA) contributions to total OA varied from 32 to 88 % (with an average contribution of 62 %) and absolute concentrations were generally under-predicted. Modelled primary hydrocarbon-like organic aerosol (HOA) and primary biomass-burning-like aerosol (BBPOA) fractions contributed to a lesser extent (HOA from 3 to 30 %, and BBPOA from 1 to 39 %) with average contributions of 13 and 25 %, respectively. Modelled BBPOA fractions were found to represent 12 to 64 % of the total residential-heating-related OA, with increasing contributions at stations located in the northern part of the domain. Source apportionment studies were performed to assess the contribution of residential and non-residential combustion precursors to the total SOA. Non-residential combustion and road transportation sector contributed about 30-40 % to SOA formation (with increasing contributions at urban and near

  17. The History of Winter: teachers as scientists

    Science.gov (United States)

    Koenig, L.; Courville, Z.; Wasilewski, P. J.; Gow, T.; Bender, K. J.

    2013-12-01

    The History of Winter (HOW) is a NASA Goddard Space Flight Center-funded teacher enrichment program that was started by Dr. Peter Wasilewski (NASA), Dr. Robert Gabrys (NASA) and Dr. Tony Gow (Cold Regions Research and Engineering Laboratory, or CRREL) in 2001 and continues with support and involvement of scientists from both the NASA Cryospheric Sciences Laboratory and CREEL. The program brings educators mostly from middle and high schools but also from state parks, community colleges and other institutions from across the US to the Northwood School (a small, private boarding school) in Lake Placid, NY for one week to learn about several facets of winter, polar, and snow research, including the science and history of polar ice core research, lake ice formation and structure, snow pack science, winter ecology, and remote sensing including current and future NASA cryospheric missions. The program receives support from the Northwood School staff to facilitate the program. The goal of the program is to create 'teachers as scientists' which is achieved through several hands-on field experiences in which the teachers have the opportunity to work with polar researchers from NASA, CRREL and partner Universities to dig and sample snow pits, make ice thin sections from lake ice, make snow shelters, and observe under-ice lake ecology. The hands-on work allows the teachers to use the same tools and techniques used in polar research while simultaneously introducing science concepts and activities to support their classroom work. The ultimate goal of the program is to provide the classroom teachers with the opportunity to learn about current and timely cryospheric research as well as to engage in real fieldwork experiences. The enthusiasm generated during the week-long program is translated into classroom activities with guidance from scientists, teachers and educational professionals. The opportunity to engage with polar researchers, both young investigators and renowned

  18. Experiment of Wireless Sensor Network to Monitor Field Data

    Directory of Open Access Journals (Sweden)

    Kwang Sik Kim

    2009-08-01

    Full Text Available Recently the mobile wireless network has been drastically enhanced and one of the most efficient ways to realize the ubiquitous network will be to develop the converged network by integrating the mobile wireless network with other IP fixed network like NGN (Next Generation Network. So in this paper the term of the wireless ubiquitous network is used to describe this approach. In this paper, first, the wireless ubiquitous network architecture is described based on IMS which has been standardized by 3GPP (3rd Generation Partnership Program. Next, the field data collection system to match the satellite data using location information is proposed based on the concept of the wireless ubiquitous network architecture. The purpose of the proposed system is to provide more accurate analyzing method with the researchers in the remote sensing area.

  19. Mapping of quantitative adult plant field resistance to leaf rust and stripe rust in two European winter wheat populations reveals co-location of three QTL conferring resistance to both rust pathogens.

    Science.gov (United States)

    Buerstmayr, Maria; Matiasch, Lydia; Mascher, Fabio; Vida, Gyula; Ittu, Marianna; Robert, Olivier; Holdgate, Sarah; Flath, Kerstin; Neumayer, Anton; Buerstmayr, Hermann

    2014-09-01

    We detected several, most likely novel QTL for adult plant resistance to rusts. Notably three QTL improved resistance to leaf rust and stripe rust simultaneously indicating broad spectrum resistance QTL. The rusts of wheat (Puccinia spp.) are destructive fungal wheat diseases. The deployment of resistant cultivars plays a central role in integrated rust disease management. Durability of resistance would be preferred, but is difficult to analyse. The Austrian winter wheat cultivar Capo was released in the 1989 and grown on a large acreage during more than two decades and maintained a good level of quantitative leaf rust and stripe rust resistance. Two bi-parental mapping populations: Capo × Arina and Capo × Furore were tested in multiple environments for severity of leaf rust and stripe rust at the adult plant stage in replicated field experiments. Quantitative trait loci associated with leaf rust and stripe rust severity were mapped using DArT and SSR markers. Five QTL were detected in multiple environments associated with resistance to leaf rust designated as QLr.ifa-2AL, QLr.ifa-2BL, QLr.ifa-2BS, QLr.ifa-3BS, and QLr.ifa-5BL, and five for resistance to stripe rust QYr.ifa-2AL, QYr.ifa-2BL, QYr.ifa-3AS, QYr.ifa-3BS, and QYr.ifa-5A. For all QTL apart from two (QYr.ifa-3AS, QLr.ifa-5BL) Capo contributed the resistance improving allele. The leaf rust and stripe rust resistance QTL on 2AL, 2BL and 3BS mapped to the same chromosome positions, indicating either closely linked genes or pleiotropic gene action. These three multiple disease resistance QTL (QLr.ifa-2AL/QYr.ifa-2AL, QLr.ifa.2BL/QYr.ifa-2BL, QLr.ifa-3BS/QYr.ifa.3BS) potentially contribute novel resistance sources for stripe rust and leaf rust. The long-lasting resistance of Capo apparently rests upon a combination of several genes. The described germplasm, QTL and markers are applicable for simultaneous resistance improvement against leaf rust and stripe rust.

  20. [Effect of swine manure application on nitrate leaching in winter wheat field in the Yellow River irrigation area of Ningxia, China].

    Science.gov (United States)

    Yang, Shi-Qi; Wang, Yong-Sheng; Xie, Xiao-Jun; Yang, Zheng-Li

    2014-06-01

    The effect of swine manure application on nitrate nitrogen leaching was investigated in the Yellow River irrigation area of Ningxia. The field experiment was conducted with 3 Treatments: Traditional fertilization 225 kg N kg x hm(-2) without swine manure (CK), traditional fertilization with swine manure 4500 kg x hm(-2) (T1) and traditional fertilization with swine manure 9000 kg x hm(-2) (T2). Nitrate nitrogen leaching rates were measured for 30, 60, 90 cm depth soil layers with a resin core absorption method. The results indicated that the nitrate leaching losses of T1 and T2 treatments ranged from 9.33 to 14.04 kg x hm(-2) (pure nitrogen), which accounted for 4.2%-6.2% of applied nitrogen fertilizer. Compared to CK, the nitrate leaching losses of T1 and T2 increased by 2.6% and 2.1% at 30 cm depth, increased by 1.5% and decreased by 1.3% at 60 cm depth, decreased by 8.7% and increased by 4.0% at 90 cm depth, respectively. The difference did not reach statistical significance among CK and T1 and T2 in nitrate leaching loss at 30, 60 and 90 cm depths. However, there was a declining trend of nitrate leaching at deep soil layers of treatments. The key period of nitrate leaching loss was from spring reviving to early filling stage, which had a higher daily leaching loss than the average of the whole growth period, and accounted for 58.7%-75.3% of total leaching loss. Compared with CK, the yields of T1 and T2 increased by 9.3% and 12.5%, respectively.

  1. Field experiment on 222Rn flux from reclaimed uranium tailings

    International Nuclear Information System (INIS)

    Hinton, T.G.

    1983-01-01

    Design and construction techniques are described for a 1.6 ha experimental uranium mill tailings reclamation plot. A passive, activated charcoal device was developed and tested for measurements of radon flux. Experiments on radon flux versus overburden depth showed that tailings covered with 1.5 m of revegetated or 0.3 m of bare overburden had exhalation rates comparable to background. Vegetated subplots exhibited a significantly higher (often an order of magnitude) flux than the bare subplots. Results on the variation of flux over time did not reveal any definitive patterns, possibly due to the high variability among replicates. A positive correlation was demonstrated between precipitation and radon flux. This is discussed in detail and possibly explained by the increase in water content of the micropores within the tailings, which increases the emanation coefficient without adversely effecting the diffusion coefficient of the overburden. 30 references, 7 figures, 3 tables

  2. Site fidelity and individual variation in winter location in partially migratory European shags.

    Directory of Open Access Journals (Sweden)

    Hannah Grist

    Full Text Available In partially migratory populations, individuals from a single breeding area experience a range of environments during the non-breeding season. If individuals show high within- and among- year fidelity to specific locations, any annual environmental effect on individual life histories could be reinforced, causing substantial demographic heterogeneity. Quantifying within- and among- individual variation and repeatability in non-breeding season location is therefore key to predicting broad-scale environmental impacts on the dynamics of partially migratory populations. We used field resightings of colour-ringed adult European shags known to have bred on the Isle of May, Scotland, to quantify individual variation and repeatability in winter location within and among three consecutive winters. In total, 3797 resightings of 882 individuals were recorded over 622 km of coastline, including the Isle of May. These individuals comprised over 50% of the known breeding population, and encompassed representative distributions of ages and sexes. The distances from the Isle of May at which individuals were resighted during winter varied substantially, up to 486 km and 136 km north and south respectively and including the breeding colony on the Isle of May. However, resighting distances were highly repeatable within individuals; within- and among-winter repeatabilities were >0.72 and >0.59 respectively across the full September-March observation period, and >0.95 and >0.79 respectively across more restricted mid-winter periods. Repeatability did not differ significantly between males and females or among different age classes, either within or among winters. These data demonstrate that the focal shag population is partially migratory, and moreover that individuals show highly repeatable variation in winter location and hence migration strategy across consecutive winters. Such high among-individual variation and within-individual repeatability, both within and

  3. Winters fuels report

    International Nuclear Information System (INIS)

    1995-01-01

    The outlook for distillate fuel oil this winter is for increased demand and a return to normal inventory patterns, assuming a resumption of normal, cooler weather than last winter. With industrial production expected to grow slightly from last winter's pace, overall consumption is projected to increase 3 percent from last winter, to 3.4 million barrels per day during the heating season (October 1, 1995-March 31, 1996). Much of the supply win come from stock drawdowns and refinery production. Estimates for the winter are from the Energy Information Administration's (EIA) 4th Quarter 1995 Short-Tenn Energy Outlook (STEO) Mid-World Oil Price Case forecast. Inventories in place on September 30, 1995, of 132 million barrels were 9 percent below the unusually high year-earlier level. Inventories of high-sulfur distillate fuel oil, the principal type used for heating, were 13 percent lower than a year earlier. Supply problems are not anticipated because refinery production and the ready availability of imports should be adequate to meet demand. Residential heating off prices are expected to be somewhat higher than last winter's, as the effects of lower crude oil prices are offset by lower distillate inventories. Heating oil is forecast to average $0.92 per gallon, the highest price since the winter of 1992-93. Diesel fuel (including tax) is predicted to be slightly higher than last year at $1.13 per gallon. This article focuses on the winter assessment for distillate fuel oil, how well last year's STEO winter outlook compared to actual events, and expectations for the coming winter. Additional analyses include regional low-sulfur and high-sulfur distillate supply, demand, and prices, and recent trends in distillate fuel oil inventories

  4. Wet winter pore pressures in railway embankments

    OpenAIRE

    Briggs, Kevin M; Smethurst, Joel A; Powrie, William; O'Brien, Anthony S

    2013-01-01

    This paper demonstrates the influence of extreme wet winter weather on pore water pressures within clay fill railway embankments, using field monitoring data and numerical modelling. Piezometer readings taken across the London Underground Ltd network following the wet winter of 2000/2001 were examined, and showed occurrences of hydrostatic pore water pressure within embankments but also many readings below this. A correlation was found between the maximum pore water pressures and the permeabi...

  5. The lure of local SETI: Fifty years of field experiments

    Science.gov (United States)

    Ailleris, Philippe

    2011-01-01

    With the commemoration in October 2007 of the Sputnik launch, space exploration celebrated its 50th anniversary. Despite impressive technological and scientific achievements the fascination for space has weakened during the last decades. One contributing factor has been the gradual disappearance of mankind's hope of discovering extraterrestrial life within its close neighbourhood. In striking contrast and since the middle of the 20th century, a non-negligible proportion of the population have already concluded that intelligent beings from other worlds do exist and visit Earth through space vehicles popularly called Unidentified Flying Objects (UFOs). In light of the continuous public interest for the UFO enigma symbolized by the recent widely diffused media announcements on the release of French and English governmental files; and considering the approach of broadening the strategies of the "Active SETI" approach and the existence of a rich multi-disciplinary UFO documentation of potential interest for SETI; this paper describes some past scientific attempts to demonstrate the physical reality of the phenomena and potentially the presence on Earth of probes of extraterrestrial origin. Details of the different instrumented field studies deployed by scientists and organizations during the period 1950-1990 in the USA, Canada and Europe are provided. In conclusion it will be argued that while continuing the current radio/optical SETI searches, there is the necessity to maintain sustaining attention to the topic of anomalous aerospace phenomena and to develop new rigorous research approaches.

  6. Activation experiments at TFTR in deuterium-tritium neutron field

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A. [California Univ., Los Angeles, CA (United States). School of Engineering and Applied Sciences; Kugel, H.W.; Ascione, G. [Princeton Plasma Physics Laboratory, Princeton University, P.O. Box 451, Princeton, NJ 08543 (United States)

    1998-09-01

    Samples of materials, of relevance to ITER and DEMO reactors, have been irradiated at TFTR in a mixed D-T and D-D neutron field over the past 3 years. The samples have been placed at various locations close to, and around, the TFTR vacuum vessel to obtain the impact of the variation of neutron energy spectrum on induced radioactivity. Intermediate measurements of decay gamma-ray activity of a number of radiated samples have contributed to an experimental database of saturation activities for aluminum, silicon, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, niobium, molybdenum, indium, silver, europium, terbium, hafnium, tungsten, rhenium, gold, 316 stainless steel, a vanadium-chromium-titanium alloy, a manganese-copper alloy, inconel 625, and inconel 718. New activity data for samples irradiated in TFTR irradiation-end 3 (external) are presented. Data for V-9Cr-5Ti alloy, inconel 718 alloy, and inconel 625 alloy are being reported for the first time. These measurements offer an invaluable opportunity for bench-marking of three-dimensional calculations of fusion neutron transport and activation for application to the design and regulatory licensing of large complex fusion reactors, such as ITER. (orig.) 7 refs.

  7. Proposal for the ZT-40 reversed-field Z-pinch experiment

    International Nuclear Information System (INIS)

    Baker, D.A.; Machalek, M.D.

    1977-08-01

    A next-generation, toroidal, reversed-field Z-pinch experiment to be constructed at LASL is proposed. On the basis of encouraging ZT-I and ZT-S experimental results, a larger device with a 40-cm bore and a 114-cm major radius is proposed, to extend the confinement time by about an order of magnitude. The new experiment will explore the physics of programming reversed-field pinches in a size range unexplored by previous reversed-field pinch experiments. Model reversed-field pinch reactor calculations show that, if stability is assumed, small fusion reactors are possible if the pinch current density is high. A basic aim will be to delineate the plasma and current density ranges in which stable reversed-field pinches can be produced. Improved vacuum techniques will be used to overcome the radiation losses that probably kept electron temperatures low in the earlier, smaller experiments

  8. Experiments and Modeling to Support Field Test Design

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Peter Jacob [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bourret, Suzanne Michelle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Zyvoloski, George Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Boukhalfa, Hakim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stauffer, Philip H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Weaver, Douglas James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-25

    Disposition of heat-generating nuclear waste (HGNW) remains a continuing technical and sociopolitical challenge. We define HGNW as the combination of both heat generating defense high level waste (DHLW) and civilian spent nuclear fuel (SNF). Numerous concepts for HGNW management have been proposed and examined internationally, including an extensive focus on geologic disposal (c.f. Brunnengräber et al., 2013). One type of proposed geologic material is salt, so chosen because of its viscoplastic deformation that causes self-repair of damage or deformation induced in the salt by waste emplacement activities (Hansen and Leigh, 2011). Salt as a repository material has been tested at several sites around the world, notably the Morsleben facility in Germany (c.f. Fahland and Heusermann, 2013; Wollrath et al., 2014; Fahland et al., 2015) and at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM. Evaluating the technical feasibility of a HGNW repository in salt is an ongoing process involving experiments and numerical modeling of many processes at many facilities.

  9. Summer fallow soil management - impact on rainfed winter wheat

    DEFF Research Database (Denmark)

    Li, Fucui; Wang, Zhaohui; Dai, Jian

    2014-01-01

    Summer fallow soil management is an important approach to improve soil and crop management in dryland areas. In the Loess Plateau regions, the annual precipitation is low and varies annually and seasonally, with more than 60% concentrated in the summer months from July to September, which...... is the summer fallow period in the winter wheat-summer fallow cropping system. With bare fallow in summer as a control, a 3-year location-fixed field experiment was conducted in the Loess Plateau to investigate the effects of wheat straw retention (SR), green manure (GM) planting, and their combination on soil...... water retention (WR) during summer fallow, winter wheat yield, and crop water use and nitrogen (N) uptake. The results showed that SR increased soil WR during summer fallow by 20 mm on average compared with the control over 3 experimental years but reduced the grain yield by 8% in the third year...

  10. Interior Vector Magnetic Field Monitoring for the SNS Neutron EDM Experiment

    Science.gov (United States)

    Nouri, Nima; Plaster, Brad

    2014-09-01

    A concept has been developed which provides for a real-time determination of the spatial dependence of the vector components of the magnetic field (and, hence, the ∂Bi / ∂xj field gradients) within the interior fiducial volume of the SNS neutron EDM experiment solely from exterior measurements at fixed discrete locations. This technique will be especially important during the operation of the experiment, when direct measurements of the field gradients present within the fiducial volume will not be physically possible. Our method, which is based on the solution to the Laplace Equation, is completely general and does not require the field to possess any type of symmetry. We describe the concept and our systematic approach for optimizing the locations of these exterior measurements. We also present results from prototyping studies of a field monitoring system deployed within a half-scale prototype of the experiment's magnetic field environment. A concept has been developed which provides for a real-time determination of the spatial dependence of the vector components of the magnetic field (and, hence, the ∂Bi / ∂xj field gradients) within the interior fiducial volume of the SNS neutron EDM experiment solely from exterior measurements at fixed discrete locations. This technique will be especially important during the operation of the experiment, when direct measurements of the field gradients present within the fiducial volume will not be physically possible. Our method, which is based on the solution to the Laplace Equation, is completely general and does not require the field to possess any type of symmetry. We describe the concept and our systematic approach for optimizing the locations of these exterior measurements. We also present results from prototyping studies of a field monitoring system deployed within a half-scale prototype of the experiment's magnetic field environment. This work was supported in part by the U.S. Department of Energy Office of

  11. Sensory ecology of water detection by bats: a field experiment.

    Directory of Open Access Journals (Sweden)

    Danilo Russo

    Full Text Available Bats face a great risk of dehydration, so sensory mechanisms for water recognition are crucial for their survival. In the laboratory, bats recognized any smooth horizontal surface as water because these provide analogous reflections of echolocation calls. We tested whether bats also approach smooth horizontal surfaces other than water to drink in nature by partly covering watering troughs used by hundreds of bats with a Perspex layer mimicking water. We aimed 1 to confirm that under natural conditions too bats mistake any horizontal smooth surface for water by testing this on large numbers of individuals from a range of species and 2 to assess the occurrence of learning effects. Eleven bat species mistook Perspex for water relying chiefly on echoacoustic information. Using black instead of transparent Perspex did not deter bats from attempting to drink. In Barbastella barbastellus no echolocation differences occurred between bats approaching the water and the Perspex surfaces respectively, confirming that bats perceive water and Perspex to be acoustically similar. The drinking attempt rates at the fake surface were often lower than those recorded in the laboratory: bats then either left the site or moved to the control water surface. This suggests that bats modified their behaviour as soon as the lack of drinking reward had overridden the influence of echoacoustic information. Regardless of which of two adjoining surfaces was covered, bats preferentially approached and attempted to drink from the first surface encountered, probably because they followed a common route, involving spatial memory and perhaps social coordination. Overall, although acoustic recognition itself is stereotyped and its importance in the drinking process overwhelming, our findings point at the role of experience in increasing behavioural flexibility under natural conditions.

  12. On transient electric fields observed in chemical release experiments by rockets

    International Nuclear Information System (INIS)

    Marklund, G.; Brenning, N.; Holmgren, G.; Haerendel, G.

    1986-06-01

    As a follow-up to the successful chemical release experiment Trigger in 1977, the TOR (Trigger Optimized Repetition) rocket was launched from Esrange on Oct. 24, 1984. Like in the Trigger experiment a large amplitude electric field pulse of 200 mV/m was detected shortly after the explosion. The central part of the pulse was found to be clearly correlated with an intense layer of swept up ambient particles behind a propagating shock-front. The field was directed towards the centre of the expanding ionized cloud, which is indicative of a polarisation electric field source. Expressions for this radial polarisation field and the much weaker azimuthal induced electric field are derived from a simple cylindrical model for the field and the expanding neutral cloud. Time profiles of the radial electric field are shown to be in good agreement with observations. (authors)

  13. Stopover ecology of Black-tailed Godwits Limosa limosa limosa in Portuguese rice fields : a guide on where to feed in winter

    NARCIS (Netherlands)

    Lourenco, Pedro M.; Piersma, Theunis

    Capsule Conservation management of rice fields may be necessary to guarantee the availability of high quality stopover habitats. Aims To analyse habitat selection and quantify the diet composition of birds. Methods Using water level and agricultural management of the fields as variables, habitat

  14. Winter predation by insectivorous birds and consequences for arthropods and plants in summer.

    Science.gov (United States)

    Barber, Nicholas A; Wouk, Jennifer

    2012-12-01

    Top-down effects of predators can have important consequences for ecosystems. Insectivorous birds frequently have strong predation effects on herbivores and other arthropods, as well as indirect effects on herbivores' host plants. Diet studies have shown that birds in temperate ecosystems consume arthropods in winter as well as in summer, but experimental studies of bird predation effects have not attempted to quantitatively separate winter predation impacts from those in summer. To understand if winter foraging by insectivorous birds has consequences for arthropods or plants, we performed a meta-analysis of published bird exclusion studies in temperate forest and shrubland habitats. We categorized 85 studies from 41 publications by whether birds were excluded year-round or only in summer, and analyzed arthropod and plant response variables. We also performed a manipulative field experiment in which we used a factorial design to exclude birds from Quercus velutina Lam. saplings in winter and summer, and censused arthropods and herbivore damage in the following growing season. In the meta-analysis, birds had stronger negative effects on herbivores in studies that included winter exclusion, and this effect was not due to study duration. However, this greater predation effect did not translate to a greater impact on plant damage or growth. In the field experiment, winter exclusion did not influence herbivore abundance or their impacts on plants. We have shown that winter feeding by temperate insectivorous birds can have important consequences for insect herbivore populations, but the strength of these effects may vary considerably among ecosystems. A full understanding of the ecological roles of insectivorous birds will require explicit consideration of their foraging in the non-growing season, and we make recommendations for how future studies can address this.

  15. Success-Breeds-Success in Collective Political Behavior: Evidence from a Field Experiment

    NARCIS (Netherlands)

    Van De Rijt, Arnout; Akin, Idil; Willer, Robb; Feinberg, Matthew

    2016-01-01

    Scholars have proposed that the emergence of political movements is highly pathdependent, such that early mobilization successes may lead to disproportionately greater eventual success. This article replicates a unique field experiment testing for positive feedback in internet petition signing (van

  16. Effect of Postsowing Compaction on Cold and Frost Tolerance of North China Plain Winter Wheat

    Directory of Open Access Journals (Sweden)

    Caiyun Lu

    2017-01-01

    Full Text Available Improper postsowing compaction negatively affects soil temperature and thereby cold and frost tolerance, particularly in extreme cold weather. In North China Plain, the temperature falls to 5 degrees below zero, even lower in winter, which is period for winter wheat growing. Thus improving temperature to promote wheat growth is important in this area. A field experiment from 2013 to 2016 was conducted to evaluate effects of postsowing compaction on soil temperature and plant population of wheat at different stages during wintering period. The effect of three postsowing compaction methods—(1 compacting wheel (CW, (2 crosskill roller (CR, and (3 V-shaped compacting roller after crosskill roller (VCRCR—on winter soil temperatures and relation to wheat shoot growth parameters were measured. Results showed that the highest soil midwinter temperature was in the CW treatment. In the 20 cm and 40 cm soil layer, soil temperatures were ranked in the following order of CW > VCRCR > CR. Shoot numbers under CW, CR, and VCRCR treatments were statistically 12.40% and 8.18% higher under CW treatment compared to CR or VCRCR treatments at the end of wintering period. The higher soil temperature under CW treatment resulted in higher shoot number at the end of wintering period, apparently due to reduced shoot death by cold and frost damage.

  17. Employment and winter construction

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Larsen, Jacob Norvig

    2011-01-01

    Reduced seasonal building activity in the construction sector is often assumed to be related to hard winter conditions for building activities and poor working conditions for construction workers, resulting in higher costs and poor quality of building products, particularly in the northern...... hemisphere. Can climatic conditions alone explain the sizeable difference in reduction in building activity in the construction sector in European countries in the winter months, or are other factors such as technology, economic cycles and schemes for financial compensation influential as well? What...... possibilities exist for reducing seasonal variation in employment? In addition to a literature review related to winter construction, European and national employment and meteorological data were studied. Finally, ministerial acts, ministerial orders or other public policy documents related to winter...

  18. Deer Wintering Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — Deer winter habitat is critical to the long term survival of white-tailed deer (Odocoileus virginianus) in Vermont. Being near the northern extreme of the...

  19. Winter Bottom Trawl Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Winter Bottom Trawl Survey was initiated in 1992 and covered offshore areas from the Mid-Atlantic to Georges Bank. Inshore strata were covered...

  20. Sample cell for in-field X-ray diffraction experiments

    Directory of Open Access Journals (Sweden)

    Viktor Höglin

    2015-01-01

    Full Text Available A sample cell making it possible to perform synchrotron radiation X-ray powder diffraction experiments in a magnetic field of 0.35 T has been constructed. The device is an add-on to an existing sample cell and contains a strong permanent magnet of NdFeB-type. Experiments have shown that the setup is working satisfactory making it possible to perform in-field measurements.

  1. Meta-analysis of field experiments shows no change in racial discrimination in hiring over time

    OpenAIRE

    Quillian, Lincoln; Pager, Devah; Hexel, Ole; Midtbøen, Arnfinn Haagensen

    2017-01-01

    This study investigates change over time in the level of hiring discrimination in US labor markets. We perform a meta-analysis of every available field experiment of hiring discrimination against African Americans or Latinos (n = 28). Together, these studies represent 55,842 applications submitted for 26,326 positions. We focus on trends since 1989 (n = 24 studies), when field experiments became more common and improved methodologically. Since 1989, whites receive on average 36% more callback...

  2. Examining the Content of Preservice Teachers' Reflections of Early Field Experiences

    Science.gov (United States)

    Subramaniam, Karthigeyan

    2013-10-01

    This paper describes an exploratory study that examined the content of preservice elementary teachers' reflections of their documented early field experiences of science teaching in authentic contexts. The study used an early field experience model that was focused on the objective of profiling an elementary science teacher as the practical merit of reflection. Preservice elementary teachers individually and collaboratively reflected on their early field experiences and used the resulting reflections to construct profiles of an elementary science teacher respectively in synthesis papers. Data sources included journal entries and synthesis papers resulting from individual and collaborative reflections. Thematic analysis revealed that profiles of an elementary science teacher constructed from both individual and collaborative reflections were based on the roles of teacher as a guide and teacher as a mediator. Analysis further revealed that classroom management and discipline and safety were the key foci factored within individual reflections while what promotes learning and the difference between what is effective and ineffective scaffolding respectively, served as the foci within collaborative reflections. Also, collaborative reflection provided a structured approach to reflection as it drew preservice elementary teachers into collective dialogue and negotiation capturing the tensions they faced when trying to make sense of the practice of other teachers. Implications include the need to frame early field experiences with objectives that are understood by all parties involved in early field experiences; and, the need to instill the importance of observation, documentation, and reflection which collectively sum up preservice teachers' early field experiences.

  3. Dealing with Design Failures in Randomized Field Experiments: Analytic Issues Regarding the Evaluation of Treatment Effects.

    Science.gov (United States)

    Gartin, Patrick R.

    1995-01-01

    Asserts that several analytical issues in randomized field experiments conducted by criminal justice scholars must be addressed more systematically. Notes that issues related to statistical power and desired sample size remain unresolved. Reviews related literature from the field of medicine to provide insights regarding the dilemmas created by…

  4. The phosphate field experiment IB 0013; annual report of the IMPHOS experiment; the ninth year: 1999

    NARCIS (Netherlands)

    Ehlert, P.A.I.; Jansen, A.G.

    2000-01-01

    The results of the ninth year of the Dutch IMPHOS field trial IB 0013 are presented. In 1999 spring barley was grown. The first stages of the growth of spring barley were positively affected by phosphorus fertilization. The more phosphorus was given, the better the crop responded. The soil structure

  5. The phosphate field experiment IB 0013; annual report of the IMPHOS experiment; the eighth year: 1998

    NARCIS (Netherlands)

    Ehlert, P.A.I.; Jansen, A.G.

    2000-01-01

    The results of the eighth year of the Dutch IMPHOS field trial IB 0013 on calcareous silt loam soil with potato are presented and discussed. At the first stages of crop growth, phosphorus fertilization had a positive effect on fresh and dry matter yields of biomass. At the final harvest the potato

  6. Entering the Field: Beginning Teachers' Positioning Experiences of the Staffroom

    Science.gov (United States)

    Christensen, Erin; Rossi, Tony; lisahunter; Tinning, Richard

    2018-01-01

    Little is known about beginning teachers' political positioning experiences of the staffroom. This paper employs Bourdieu's conceptual tools of field, habitus and capital to explore beginning health and physical education teachers' positioning experiences and learning in staffrooms, the place in which teachers spend the majority of their…

  7. Preservice Science Teachers' Field Experiences with Educational Technologies as Part of Portfolio Development: A Turkish Perspective

    Science.gov (United States)

    Korkmaz, Hunkar; Gucum, Berna; Hakverdi, Meral

    2006-01-01

    The purpose of this study is to assess the usage of educational technology of pre-service science teachers in their field experiences. This study was carried out on 45 pre-service science teachers taking School Experience and Practice Teaching courses at Hacettepe University in Turkey. The data were obtained from the evaluation of pre-service…

  8. Seventh Fleet field training exercise : Fleet Battle Experiment Kilo : fires initiatives final report

    OpenAIRE

    Schacher, G. E. (Gordon Everett); Pilnick, Steve; Irvine, Nelson; Gallup, Shelley

    2003-01-01

    Fleet Battle Experiment Kilo was conducted during Seventh Fleet exercise Tandem Thrust 03. During the Field Training Exercise phase, testing of Time Sensitive Targets processes using the Joint Fires Network was carried out. This report contains results obtained on contributions made by the Joint Fires Network to Navy Time Sensitive Targeting and experiment lessons learned. NA

  9. Compensation effect of winter wheat grain yield reduction under straw mulching in wide-precision planting in the North China Plain

    OpenAIRE

    Liu, Xinhui; Ren, Yujie; Gao, Chao; Yan, Zhenxing; Li, Quanqi

    2017-01-01

    Climate change and the growing demand for food security force growers to identify ways both to improve food production and to reduce agricultural carbon emissions. Although straw mulching is known to decrease CO2 emissions, winter wheat grain yield in the North China Plain was declined under straw mulching. In an effort to determine the most effective way to increase winter wheat yield under straw mulching, a field experiment was conducted using two planting patterns (wide-precision planting ...

  10. Root development of fodder radish and winter wheat before winter in relation to uptake of nitrogen

    DEFF Research Database (Denmark)

    Wahlström, Ellen Margrethe; Hansen, Elly Møller; Mandel, A.

    2015-01-01

    The nitrate (N) present in soil at the end of autumn is prone to leach during winter and spring in temperate climates if not taken up by plants. In Denmark catch crops are used as a regulatory tool to reduce N leaching and therefore a shift from winter cereals to spring cereals with catch crops has...... occurred. Quantitative data is missing on N leaching of a catch crop compared to a winter cereal in a conventional cereal-based cropping system. The aim of the study was to investigate whether fodder radish (Raphanus sativus L.) (FR) would be more efficient than winter wheat (Triticum aestivum L.) (WW......) at depleting the soil of mineral nitrogen (Nmin) before winter. A secondary aim was to study the agreement between three different root measuring methods: root wash (RW), core break (CB) and minirhizotron (MR). The third aim of the was to correlate the N uptake of FR and WW with RLD. An experiment was made...

  11. Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

    Science.gov (United States)

    Davtyan, D.; Machluf, S.; Soudijn, M. L.; Naber, J. B.; van Druten, N. J.; van Linden van den Heuvell, H. B.; Spreeuw, R. J. C.

    2018-02-01

    Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than 0.2 V /cm at 78 μ m from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.

  12. Rocket to Creativity: A Field Experience in Problem-Based and Project-Based Learning

    Directory of Open Access Journals (Sweden)

    Sharon F. Dole

    2016-11-01

    Full Text Available The purpose of this article is to examine the impact of a field experience in problem-based (PBL and project-based learning (PjBL on pre-service and in-service teachers’ conceptions of experiential learning. In our study, participants had been enrolled in a hybrid class that included an online component in which they learned about PBL and PjBL and an experiential component in which they facilitated PBL and PjBL with children in grades 1-9 during a one-week field experience on a university campus. The goal of the field experience is for teachers to change their practice from didactic to inquiry and to promote critical and creative thinking in their students. We used a case study method that involved data derived from six different sources: online structured interviews, follow-up telephone interviews, discussion board posts, reflections, course feedback, and observations. The main theme that emerged from the data analysis was the critical role the field experience played in applying theory to practice. Sub-themes included understanding the process of implementing PBL and PjBL, mastering the logistics of PBL and PjBL, becoming facilitators, and collaborating with partners. Results showed that the field experience gave the teachers the “courage” to experiment with a student-centered methodology.

  13. Integration of Field Geophysics and Geology in an International Setting: Multidisciplinary Geoscience Field Experience at the University of Western Ontario

    Science.gov (United States)

    Brenders, A. J.; Banerjee, N.; Pratt, R. G.

    2010-12-01

    The pedagogical value of the field experience is unequaled: students, teaching assistants, and professors alike return with a renewed sense of purpose, community, and the context in which to place classroom education. It is widely regarded as valuable to personal development, and is required by the Canadian Council of Professional Geoscientists for professional registration. As part of our ongoing International Geoscience Field Experience Initiative, Earth Sciences students at the University of Western Ontario have the opportunity to enhance their education through a study abroad program. The focus is on a residential field experience to world-class localities, offered with the collaboration of internationally recognized academic researchers, government survey personnel, and industry leaders. Recent trips have included the Sn-W mineralization in the Cornwall district of the U.K., the Iberian Pyrite Belt (IPB) in Portugal and Spain, and the metallogenic belts of Western Turkey. The integration of geological knowledge with geophysical data was one of the key organizing principles of our recent field trips to the IPB and Western Turkey. This integration is a foundation of modern Earth Sciences, and common practice in industry, it is relatively rare in classroom settings. Lectures before departure and evening exercises during the field trip supplemented the core undergraduate curriculum in geophysics, reviewing gravity, DC resistivity, induced polarization (IP), and magnetotelluric methods, focusing on application to mineral exploration. During our trip to the IPB, partnership with industry allowed students the opportunity to work with state of the art geophysical data, acquired on an exploration prospect visited during the field trip. Multi-parameter geophysical inversions of the IP and MT data produced cross-sections in depth - results interpretable by the students in the complex geological environment of the Iberian Pyrite Belt. Although the students gained valuable

  14. Effects of imidacloprid and clothianidin seed treatments on wheat aphids and their natural enemies on winter wheat.

    Science.gov (United States)

    Zhang, Peng; Zhang, Xuefeng; Zhao, Yunhe; Wei, Yan; Mu, Wei; Liu, Feng

    2016-06-01

    Wheat aphid (Hemiptera: Aphididae) is one of the major pests of winter wheat and has posed a significant threat to winter wheat production in China. Although neonicotinoid insecticidal seed treatments have been suggested to be a control method, the season-long efficacy on pests and the impact on their natural enemies are still uncertain. Experiments were conducted to determine the efficacy of imidacloprid and clothianidin on the control of aphids, the number of their natural enemies and the emergence rate and yield of wheat during 2011-2014. Imidacloprid and clothianidin seed treatments had no effect on the emergence rate of winter wheat and could prevent yield losses and wheat aphid infestations throughout the winter wheat growing season. Furthermore, their active ingredients were detected in winter wheat leaves up to 200 days after sowing. Imidacloprid and clothianidin seed treatments had no adverse effects on ladybirds, hoverflies or parasitoids, and instead increased the spider-aphid ratios. Wheat seeds treated with imidacloprid and clothianidin were effective against wheat aphids throughout the winter wheat growing season and reduced the yield loss under field conditions. Imidacloprid and clothianidin seed treatments may be an important component of the integrated management of wheat aphids on winter wheat. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  15. Reviewing Special Education Teacher Preparation Field Experience Placements, Activities, and Research: Do We Know the Difference Maker?

    Science.gov (United States)

    Nagro, Sarah A.; deBettencourt, Laurie U.

    2017-01-01

    There is a paucity of research on what constitutes an ideal special education field experience, and it is not clear which components or activities within a field experience impact a teacher's growth to the greatest extent. Reviewing past research will assist in categorizing the components typically included in field experiences and may assist in…

  16. The nuclear winter

    International Nuclear Information System (INIS)

    Velikhow, Y.P.

    1986-01-01

    Nuclear winter is an example of possible secondary effects, and if we speak of secondary we are thinking of small-scale second-order effects, but a nuclear winter is not a second-order effect. If you calculate the amount of heat produced by a nuclear explosion, it is a very small amount which does not have any chance of changing the Earth's climate, but a nuclear explosion drives or stars some new mechanism - the mechanism of nuclear winter - after 100 megatons of dust are transferred to the upper atmosphere. Another example of such amplification is radioactive fall-out, especially long-life radioactive fall-out after the possible elimination of the nuclear power industry, nuclear storage and distribution of storage waste around the globe. This is a very powerful amplification mechanism

  17. Phytoplankton response to winter warming modified by large-bodied zooplankton: an experimental microcosm study

    Directory of Open Access Journals (Sweden)

    Hu He

    2015-03-01

    Full Text Available While several field investigations have demonstrated significant effects of cool season (winter or spring warming on phytoplankton development, the role played by large-bodied zooplankton grazers for the responses of phytoplankton to winter warming is ambiguous. We conducted an outdoor experiment to compare the effect of winter warming (heating by 3°C in combination with presence and absence of Daphnia grazing (D. similis on phytoplankton standing crops and community structure under eutrophic conditions. When Daphnia were absent, warming was associated with significant increases in phytoplankton biomass and cyanobacterial dominance. In contrast, when Daphnia were present, warming effects on phytoplankton dynamics were offset by warming-enhanced grazing, resulting in no significant change in biomass or taxonomic dominance. These results emphasize that large-bodied zooplankton like Daphnia spp. may play an important role in modulating the interactions between climate warming and phytoplankton dynamics in nutrient rich lake ecosystems.

  18. Simulation of Winter Wheat Yield with WOFOST in County Scale

    OpenAIRE

    Ma, Shangjie; Pei, Zhiyuan; He, Yajuan; Wang, Lianlin; Ma, Zhiping

    2015-01-01

    International audience; Winter wheat is mainly planted in water shortage area, such as North China and Northwest China. As a key field management measure, irrigation plays an important role in the production of winter wheat. This paper focuses on the improvement of regional winter wheat yield estimation technique in county scale by adjusting the irrigation management measure in crop growth model. The WOFOST (World Food Study) model was used by dividing the whole county into a number of EMUs (...

  19. Experiences of radiostimulation in small-plot fields. Experiments in 1978

    International Nuclear Information System (INIS)

    Pannonhalmi, K.

    1979-01-01

    In 1978 radiostimulation experiments were conducted on a total of 18 ha, using 41 varieties of 13 plant species. This paper deals with some aspects of the work in relation to maize, carrots, paprika for spice and cucumbers. According to the observations the importance of gamma irradiating isotopes with different energy spectra exceeded that of dose intensity in the case of maize. In some hybrids yield response was obtained with 137 Cs gamma treatment, in others with 60 Co gamma treatment. Carrot yield exhibited an unambiguous and considerable increase by the influence of irradiation. The changes in the growing season and crop yield of paprika for spice were dependent on the variety. The two cucumber varieties studied responded differently to irradiation. Early and increased yield was obtained for the Buda gherkins. The Nimbus variety exhibited no stimulation effect. The addition of gibberellic acid resulted in larger yield for the Nimbus variety while no response was obtained with the Buda gherkin variety. (author)

  20. The study of seasonal composition and dynamics of wetland ecosystems and wintering bird habitat at Poyang Lake, PR China using object-based image analysis and field observations

    Science.gov (United States)

    Dronova, Iryna

    Wetlands are among the most productive ecosystems in the world which support critical ecological services and high biological diversity yet are vulnerable to climate change and human activities. In this thesis, I investigated the capabilities of satellite remote sensing with medium spatial resolution and object-based image analysis (OBIA) methods to elucidate seasonal composition and dynamics of wetland ecosystems and indicators of habitat for wintering waterbirds in a large conservation hotspot of Poyang Lake, PR China. I first examined changes in major wetland cover types during the low water period when Poyang Lake provides habitat to large numbers of migratory birds from the East Asian pathway. I used OBIA to map and analyze the transitions among water, vegetation, mudflat and sand classes from four 32-m Beijing-1 microsatellite images between late fall 2007 and early spring 2008. This analysis revealed that, while transitions among wetland classes were strongly associated with precipitation and flood-driven hydrological variation, the overall dynamics were a more complex interplay of vegetation phenology, disturbance and post-flood exposure. Remote sensing signals of environmental processes were more effectively captured by changes in fuzzy memberships to each class per location than by changes in spatial extents of the best-matching classes alone. The highest uncertainty in the image analysis corresponded to transitional wetland states at the end of the major flood recession in November and to heterogeneous mudflat areas at the land-water interface during the whole study period. Results suggest seasonally exposed mudflat features as important targets for future research due to heterogeneity and uncertainty of their composition, variable spatial distribution and sensitivity to hydrological dynamics. I further explored the potential of OBIA to overcome the limitations of the traditional pixel-based image classification methods in characterizing Poyang Lake

  1. Using Magnetic Field Gradients to Simulate Variable Gravity in Fluids and Materials Experiments

    Science.gov (United States)

    Ramachandran, Narayanan

    2006-01-01

    Fluid flow due to a gravitational field is caused by sedimentation, thermal buoyancy, or solutal buoyancy induced convection. During crystal growth, for example, these flows are undesirable and can lead to crystal imperfections. While crystallization in microgravity can approach diffusion limited growth conditions (no convection), terrestrially strong magnetic fields can be used to control fluid flow and sedimentation effects. In this work, a theory is presented on the stability of solutal convection of a magnetized fluid(weak1y paramagnetic) in the presence of a magnetic field. The requirements for stability are developed and compared to experiments performed within the bore of a superconducting magnet. The theoretical predictions are in good agreement with the experiments. Extension of the technique can also be applied to study artificial gravity requirements for long duration exploration missions. Discussion of this application with preliminary experiments and application of the technique to crystal growth will be provided.

  2. Summer fallow soil management - impact on rainfed winter wheat

    DEFF Research Database (Denmark)

    Li, Fucui; Wang, Zhaohui; Dai, Jian

    2014-01-01

    is the summer fallow period in the winter wheat-summer fallow cropping system. With bare fallow in summer as a control, a 3-year location-fixed field experiment was conducted in the Loess Plateau to investigate the effects of wheat straw retention (SR), green manure (GM) planting, and their combination on soil...... water retention (WR) during summer fallow, winter wheat yield, and crop water use and nitrogen (N) uptake. The results showed that SR increased soil WR during summer fallow by 20 mm on average compared with the control over 3 experimental years but reduced the grain yield by 8% in the third year...... and the grain N content by 6–15% in all 3 years. In contrast, GM planting markedly reduced soil WR by 16 mm and 33 mm in the first and third year, respectively, but increased water use efficiency (WUE) by 16% in the third year and nitrate N accumulation in 0–100 cm soil at winter wheat sowing. Their combination...

  3. Field-reversal experiments in the mirror fusion test facility (MFTF)

    International Nuclear Information System (INIS)

    Shearer, J.W.; Condit, W.C.

    1977-01-01

    Detailed consideration of several aspects of a field-reversal experiment was begun in the Mirror Fusion Test Facility (MFTF): Model calculations have provided some plausible parameters for a field-reversed deuterium plasma in the MFTF, and a buildup calculation indicates that the MFTF neutral-beam system is marginally sufficient to achieve field reversal by neutral injection alone. However, the many uncertainties indicate the need for further research and development on alternate buildup methods. A discussion of experimental objectives is presented and important diagnostics are listed. The range of parameter space accessible with the MFTF magnet design is explored, and we find that with proper aiming of the neutral beams, meaningful experiments can be performed to advance toward these objectives. Finally, it is pointed out that if we achieve enhanced n tau confinement by means of field reversal, then quasi-steady-state operation of MFTF is conceivable

  4. Awareness descriptions of three PTSD diagnosed patients’ inner experiences before, during and after Thought Field Therapy.

    OpenAIRE

    Martinussen, Anita

    2016-01-01

    SUMMARY Background Thought Field Therapy (TFT) is a psychotherapeutic modality often utilised for single-session trauma treatment. It applies sensory stimulation to desensitise painful feelings, and may thus be called a psycho-sensory therapy. Qualitative research on TFT is particularly scarce, and this processual study seeks to fill that void. Research question How do PTSD patients describe their inner experiences before, during and after Thought Field Therapy? Method Three patients diagnose...

  5. The Role of Laboratory Experiments in the Validation of Field Data

    DEFF Research Database (Denmark)

    Mouneyrac, Catherine; Lagarde, Fabienne; Chatel, Amelie

    2017-01-01

    wide range of materials with different sizes, shapes, chemical natures and physicochemical properties, and their quantities/concentrations are highly variable depending on location and sampling and quantification protocols. To provide comprehensive data, interactions of MPs with the environment (water...... of Field Data | Request PDF. Available from: https://www.researchgate.net/publication/310360438_The_Role_of_Laboratory_Experiments_in_the_Validation_of_Field_Data [accessed Jan 15 2018]....

  6. Electronic ground support equipment for the Cluster Electric Field and Wave Experiment

    International Nuclear Information System (INIS)

    Sten, T.A.

    1992-10-01

    In a collaboration between ESA and NASA, ionosphere plasma structures will be studied by four indentical space probes to be launched in 1995 from French Guiana. The Electric Field and Wave (EFW) experiment will be designed to measure electric field and density fluctations by means of four sensors, each deployed on a 50 meter wire boom. In order to perform comprehensive tests and calibrations of the EFW experiment, computer controlled electronic ground support equipment has been developed. This report describes the hardware of the equipment, produced and assembled at the University of Oslo. 15 figs

  7. 'The Real Classroom Is Outside—Get into It!' Teaching through Field Experiences

    Science.gov (United States)

    Passow, M. J.

    2015-12-01

    Field-based experiences can be powerful influences on students of any age, from pre-college through grad school, as well as on the general public. Every place-based learning experience will be different because the combination of location, participant background, available resources, and other factors will be unique. But certain shared goals, necessities, and similarities can be recognized. Intended outcomes should be identified in advance to inform planning. Preparation for field experiences should involve the students along with other participants. More-experienced students can become role models for new-comers. Field experiences involve active learning, as participants are fully immersed in the sampling site and have all senses stimulated. Constantly-changing variables highlight interconnectedness of Earth processes and fosters Systems Thinking. Decisions about the most effective ways to communicate data and results will differ from what might be based on classroom or laboratory venues. Three examples of field-based learning will be provided. One involves collaboration between educational specialists at a scientific research institution, the Lamont-Doherty Earth Observatory of Columbia University, with high school students enrolled in their school's Authentic Science Research program. The second describes orientation for beginning graduate students to the geology, geography, and history of their new home region through a tourist boat ride, the well-known Circle Ride around Manhattan. The third illustrates use of 'eco-hikes' to enhance environmental understanding for Open House and other visitors. These can serve as models for designing experience-based programs in other situations.

  8. Titan's Emergence from Winter

    Science.gov (United States)

    Flasar, F. Michael; Achterberg, Richard; Jennings, Donald; Schinder, Paul

    2011-01-01

    We summarize the changes in Titans thermal structure derived from Cassini CIRS and radio-occultation data during the transition from winter to early spring. Titan's surface, and middle atmosphere show noticeable seasonal change, whereas that in most of the troposphere is mated. This can be understood in terms of the relatively small radiative relaxation time in the middle atmosphere and much larger time scale in the troposphere. The surface exhibits seasonal change because the heat capacity in an annual skin depth is much smaller than that in the lowest scale height of the troposphere. Surface temperatures rise 1 K at raid and high latitudes in the winter northern hemisphere and cool in the southern hemisphere. Changes in in the middle atmosphere are more complicated. Temperatures in the middle stratosphere (approximately 1 mbar) increase by a few kelvin at mid northern latitudes, but those at high latitudes first increase as that region moves out of winter shadow, and then decrease. This probably results from the combined effect of increased solar heating as the suit moves higher in the sky and the decreased adiabatic warming as the sinking motions associated with the cross-equatorial meridional cell weaken. Consistent with this interpretation, the warm temperatures observed higher up at the winter polar stratopause cool significantly.

  9. Field experience in science for fifth grade students---a mixed methods study of learning environments

    Science.gov (United States)

    Patterson, Barbara E.

    The purpose of this research is to compare students' perceptions of the learning environment in a traditional science classroom and a field study classroom. This mixed methods study used a sequential explanatory design. Phase one was the quantitative phase using two survey tools. A modified version of the "What is happening in this Classroom Survey" (WIHIC) (Fraser et al., 1996) and the "Test of Science Related Attitudes" (TOSRA) (Fraser, 1982) was administered to 60 fifth grade students from one school. Data was then disaggregated by socioeconomic class and ethnicity. Results from Phase one showed that students prefer the classroom for investigation and prefer the field environment for enjoyment of science. Differences in ethnicity and class were small but Hispanic students prefer the field for investigation and equity. Students that are low socio-economic class rank cooperation in the field higher than the classroom and students that do not qualify for free or reduced lunch prefer the field environment for enjoyment of science. Finally, there are strong correlations for the variables of cooperation, investigation, equity and enjoyment of science in both the classroom and the field environment. Questions raised from the analysis of the survey data were further explored through qualitative data collection methods in phase two. Student responses to three questions were coded using template analysis to provide answers to the "how and why" field experience effects students' attitudes toward science. Three themes emerged from the coding of the results. These results showed that students are physically engaged, develop a sense of place and learn skills in the field that reinforce concepts learned in the classroom. This information will help teachers in developing quality and meaningful experiences for all students. "Closing the gaps among minority groups while improving achievement of all students constitutes the dual goals of education in the nation" (Lee et al., 2004

  10. Field assessment of the mid winter mass kills of trophic fishes at Mariotteya stream, Egypt: chemical and biological pollution synergistic model.

    Science.gov (United States)

    Eissa, A E; Tharwat, N A; Zaki, M M

    2013-01-01

    Pathogenic Candida albicans was isolated from water and fish samples collected during an emergent event of mass mortalities among the juvenile Nile tilapia (Oreochromis niloticus), Sharp toothed catfish (Clarias gariepinus) along the stream of Mariotteya drainage. Investigations indicated that fish mortalities were confined to the area of Shubramant and Aboul Noumros (North to Sakara 7 drainage). C. albicans was isolated from the lesions associated with multiple skin ulcers in both Nile tilapia juveniles and Sharp toothed catfish. Assessment of the field and laboratory data has indicated that Mariotteya environmental disaster was a multifactorial problem. The fish mass kills were initially flared up through the dumping of the improperly treated nasty organic and inorganic chemicals from Elhawamdia sugar factory and municipal sewage. The physical stagnation of the stream, high levels of ammonia, phenol and polycyclic aromatic hydrocarbons (PAHs) and low levels of dissolved oxygen (DO) were all incriminated as the initial stimulus behind biological invasion of pathogenic bacteria (Pseudomonas fluorescence) and yeast (C. albicans). Pathologically, fishes were dying from both respiratory and osmoregulatory failure induced by the severe damage of both gills and skin. It has been implied that such environmental pollutants have direct damaging effects on gills, skin and fins with consequent suppression of the skin's natural innate components. The adversely confronted immunological barriers were further exacerbated by the possible synergistic interactions of P. fluorescence dermotropic toxins followed by the secondary invasion of the pathogenic C. albicans. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Ultrafast electron field emission from gold resonant antennas studied by two terahertz pulse experiments

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Zalkovskij, Maksim; Strikwerda, Andrew C.

    2015-01-01

    Summary form only given. Ultrafast electron field emission from gold resonant antennas induced by strong terahertz (THz) transient is investigated using two THz pulse experiments. It is shown that UV emission from nitrogen plasma generated by liberated electrons is a good indication of the local...... electric field at the antenna tip. Using this method resonant properties of antennas fabricated on high resistivity silicon are investigated in the strong field regime. Decrease of antenna Q-factor due to ultrafast carrier multiplication in the substrate is observed....

  12. Effects of a PID Control System on Electromagnetic Fields in an nEDM Experiment

    Science.gov (United States)

    Molina, Daniel

    2017-09-01

    The Kellogg Radiation Laboratory is currently testing a prototype for an experiment that hopes to identify the electric dipole moment of the neutron. As part of this testing, we have developed a PID (proportional, integral, derivative) feedback system that uses large coils to fix the value of local external magnetic fields, up to linear gradients. PID algorithms compare the current value to a set-point and use the integral and derivative of the field with respect to the set-point to maintain constant fields. We have also developed a method for zeroing linear gradients within the experimental apparatus. In order to determine the performance of the PID algorithm, measurements of both the internal and external fields were obtained with and without the algorithm running, and these results were compared for noise and time stability. We have seen that the PID algorithm can reduce the effect of disturbance to the field by a factor of 10.

  13. A 7 T Pulsed Magnetic Field Generator for Magnetized Laser Plasma Experiments

    Science.gov (United States)

    Hu, Guangyue; Liang, Yihan; Song, Falun; Yuan, Peng; Wang, Yulin; Zhao, Bin; Zheng, Jian

    2015-02-01

    A pulsed magnetic field generator was developed to study the effect of a magnetic field on the evolution of a laser-generated plasma. A 40 kV pulsed power system delivered a fast (~230 ns), 55 kA current pulse into a single-turn coil surrounding the laser target, using a capacitor bank of 200 nF, a laser-triggered switch and a low-impedance strip transmission line. A one-dimensional uniform 7 T pulsed magnetic field was created using a Helmholtz coil pair with a 6 mm diameter. The pulsed magnetic field was controlled to take effect synchronously with a nanosecond heating laser beam, a femtosecond probing laser beam and an optical Intensified Charge Coupled Device (ICCD) detector. The preliminary experiments demonstrate bifurcation and focusing of plasma expansion in a transverse magnetic field.

  14. Magnetic Field Monitoring in the SNS and LANL Neutron EDM Experiments

    Science.gov (United States)

    Aleksandrova, Alina; SNS nEDM Collaboration; LANL nEDM Collaboration

    2017-09-01

    The SNS neutron EDM experiment requires the ability to precisely control and monitor the magnetic field inside of the fiducial volume. However, it is not always practical (or even possible) to measure the field within the region of interest directly. To remedy this issue, we have designed a field monitoring system that will allow us to reconstruct the field inside of the fiducial volume using noninvasive measurements of the field components at discrete locations external to this volume. A prototype probe array (consisting of 12 single-axis fluxgate magnetometer sensors) was used to monitor the magnetic field within the fiducial volume of an in-house magnetic testing apparatus. In this talk, the design and results of this test will be presented, and the possible implementation of this field monitoring method may have in the room temperature LANL neutron EDM experiment will be discussed. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Award Number DE-SC-0014622.

  15. Self-generated magnetic fields in direct-drive implosion experiments

    Science.gov (United States)

    Igumenshchev, I. V.; Zylstra, A. B.; Li, C. K.; Nilson, P. M.; Goncharov, V. N.; Petrasso, R. D.

    2014-06-01

    Electric and self-generated magnetic fields in direct-drive implosion experiments on the OMEGA Laser Facility were investigated employing radiography with ˜10- to 60-MeV protons. The experiment used plastic-shell targets with imposed surface defects (glue spots, wires, and mount stalks), which enhance self-generated fields. The fields were measured during the 1-ns laser drive with an on-target intensity ˜1015 W/cm2. Proton radiographs show multiple ring-like structures produced by electric fields ˜107 V/cm and fine structures from surface defects, indicating self-generated fields up to ˜3 MG. These electric and magnetic fields show good agreement with two-dimensional magnetohydrodynamic simulations when the latter include the ∇Te × ∇ne source, Nernst convection, and anisotropic resistivity. The simulations predict that self-generated fields affect heat fluxes in the conduction zone and, through this, affect the growth of local perturbations.

  16. Experience-based Learning in Acadia National Park: a Successful, Long-running, Model Field Course

    Science.gov (United States)

    Connaughton, M.

    2015-12-01

    This two-week field course has been offered alternate summers since 2000 in Acadia National Park on Mount Desert Island, Maine and addresses the geological history, physical and biological oceanography and principles of community ecology applicable to terrestrial and/or marine communities of coastal Maine. The course is often transformative and deeply meaningful to the students, many of whom have limited travel experience. The essential components of experience-based learning are well represented in this class with multiple opportunities for abstract conceptualization, active experimentation, concrete hands-on experiences and reflective observation built into the course. Each day begins with a lecture introducing concepts, which are then made concrete though daily field trips (4-8 hours in duration) into the park that include rigorous hiking, some kayaking and one commercial nature cruise. Field trips include hands-on experience with lecture concepts, on-site lessons in field methods, and data collection for independent projects. Each field trip is tied to a specific independent project, which are generated by the instructor, but self-selected by the students. Every student is actively involved in data collection during each field trip, with one student in charge of the collection each day. Daily guided journaling in three parts (scientific, personal and creative) and evening discussions provide ample opportunity for the student to reflect on the scientific content of the course, examine their personal reactions to what they have experienced and to be creative, sharing prior experiences, prior learning and their personalities. The course includes two exams, each following a week of lecture and field experiences. Independent research projects include the production of a manuscript-formatted report complete with statistical analysis of the data and a literature-based discussion of the conclusions. The combination of experiential reinforcement of concepts, abundant

  17. Enabling Field Experiences in Introductory Geoscience Classes through the Use of Immersive Virtual Reality

    Science.gov (United States)

    Moysey, S. M.; Smith, E.; Sellers, V.; Wyant, P.; Boyer, D. M.; Mobley, C.; Brame, S.

    2015-12-01

    Although field experiences are an important aspect of geoscience education, the opportunity to provide physical world experiences to large groups of introductory students is often limited by access, logistical, and financial constraints. Our project (NSF IUSE 1504619) is investigating the use of immersive virtual reality (VR) technologies as a surrogate for real field experiences in introductory geosciences classes. We are developing a toolbox that leverages innovations in the field of VR, including the Oculus Rift and Google Cardboard, to enable every student in an introductory geology classroom the opportunity to have a first-person virtual field experience in the Grand Canyon. We have opted to structure our VR experience as an interactive game where students must explore the Canyon to accomplish a series of tasks designed to emphasize key aspects of geoscience learning. So far we have produced two demo products for the virtual field trip. The first is a standalone "Rock Box" app developed for the iPhone, which allows students to select different rock samples, examine them in 3D, and obtain basic information about the properties of each sample. The app can act as a supplement to the traditional rock box used in physical geology labs. The second product is a fully functioning VR environment for the Grand Canyon developed using satellite-based topographic and imagery data to retain real geologic features within the experience. Players can freely navigate to explore anywhere they desire within the Canyon, but are guided to points of interest where they are able to complete exercises that will be aligned with specific learning goals. To this point we have integrated elements of the "Rock Box" app within the VR environment, allowing players to examine 3D details of rock samples they encounter within the Grand Canyon. We plan to provide demos of both products and obtain user feedback during our presentation.

  18. Porous media experience applicable to field evaluation for compressed air energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Gutknecht, P.J.

    1980-06-01

    A survey is presented of porous media field experience that may aid in the development of a compressed air energy storage field demonstration. Work done at PNL and experience of other groups and related industries is reviewed. An overall view of porous media experience in the underground storage of fluids is presented. CAES experience consists of site evaluation and selection processes used by groups in California, Kansas, and Indiana. Reservoir design and field evaluation of example sites are reported. The studies raised questions about compatibility with depleted oil and gas reservoirs, storage space rights, and compressed air regulations. Related experience embraces technologies of natural gas, thermal energy, and geothermal and hydrogen storage. Natural gas storage technology lends the most toward compressed air storage development, keeping in mind the respective differences between stored fluids, physical conditions, and cycling frequencies. Both fluids are injected under pressure into an aquifer to form a storage bubble confined between a suitable caprock structure and partially displaced ground water. State-of-the-art information is summarized as the necessary foundation material for field planning. Preliminary design criteria are given as recommendations for basic reservoir characteristics. These include geometric dimensions and storage matrix properties such as permeability. Suggested ranges are given for injection air temperature and reservoir pressure. The second step in developmental research is numerical modeling. Results have aided preliminary design by analyzing injection effects upon reservoir pressure, temperature and humidity profiles. Results are reported from laboratory experiments on candidate sandstones and caprocks. Conclusions are drawn, but further verification must be done in the field.

  19. Application verification research of cloud computing technology in the field of real time aerospace experiment

    Science.gov (United States)

    Wan, Junwei; Chen, Hongyan; Zhao, Jing

    2017-08-01

    According to the requirements of real-time, reliability and safety for aerospace experiment, the single center cloud computing technology application verification platform is constructed. At the IAAS level, the feasibility of the cloud computing technology be applied to the field of aerospace experiment is tested and verified. Based on the analysis of the test results, a preliminary conclusion is obtained: Cloud computing platform can be applied to the aerospace experiment computing intensive business. For I/O intensive business, it is recommended to use the traditional physical machine.

  20. Sound Design in Virtual Reality Concert Experiences using a Wave Field Synthesis Approach

    DEFF Research Database (Denmark)

    Lind, Rasmus Bloustrød; Milesen, Victor; Smed, Dina Madsen

    2017-01-01

    In this paper we propose an experiment that evaluates the influence of audience noise on the feeling of presence and the perceived quality in a virtual reality concert experience delivered using Wave Field Synthesis. A 360 degree video of a live rock concert from a local band was recorded. Single...... with 30 participants we found that audience noise does not have a significant impact on presence. However, qualitative evaluations show that the naturalness of the sonic experience delivered through wavefield synthesis had a positive impact on the participants....

  1. [Winter sport injuries in childhood (author's transl)].

    Science.gov (United States)

    Hausbrandt, D; Höllwarth, M; Ritter, G

    1979-01-01

    3374 accidents occurring on the field of sport during the years 1975--1977 accounted for 19% of all accidents dealt with at the Institute of Kinderchirurgie in Graz. 51% of the accidents were caused by the typical winter sports: skiing, tobogganing, ice-skating and ski-jumping with skiing accounting for 75% of the accidents. The fracture localization typical of the different kinds of winter sport is dealt with in detail. The correct size and safety of the equipment were found to be particularly important in the prevention of such accidents in childhood.

  2. Remote Diagnosis of Nitrogen Status in Winter Oilseed Rape

    Science.gov (United States)

    Liu, S.

    2016-12-01

    Winter oilseed rape is one of the most important oilseed crops in the world. Compared with cereal crops, it requires high amount of nitrogen (N) supplies, but it is also characterized by low N use efficiency. The N nutrition index (NNI), defined as the ratio of the actual plant N concentration (PNC) to the critical PNC at a given biomass level, has been widely used to diagnose plant N status and to aid optimizing N fertilization. But traditional techniques to determine NNI in the lab are time-consuming and expensive. Remote sensing provides a promising approach for large-scale and rapid monitoring and diagnosis of crop N status. In this study, we conducted the experiment in the winter oilseed rape field with eight fertilization treatments in the growing season of 2014 and 2015. PNC, dry mass, and canopy spectra were measured during the different growth stages of winter oilseed rape. The N dilution curve was developed with measurements, and NNI was computed and analyzed for different treatments and different growth stage. For the same treatment, NNI decreased as more leaves were developing. Two methods were applied to remotely estimating NNI for winter oilseed rape: (1) NNI was estimated directly with vegetation indices (VIs) derived from canopy spectra; (2) the actual PNC and the critical PNC at the given biomass level were estimated separately with different types of VIs, and NNI was then computed with the two parts of the estimations. We found that VIs based solely on bands in the visible region provided the most accurate estimates of PNC. Estimating NNI directly with VIs had better performance than estimating the actual PNC and the critical PNC separately.

  3. [Effects of sprinkler irrigation amount on winter wheat growth, water consumption, and water use efficiency].

    Science.gov (United States)

    Yu, Li-Peng; Huang, Guan-Hua; Liu, Hai-Jun; Wang, Xiang-Ping; Wang, Ming-Qiang

    2010-08-01

    In 2006-2008, a field experiment was conducted at the Tongzhou Experimental Base for Water-Saving Irrigation Research, Chinese Academy of Sciences, Beijing, aimed to study the effects of sprinkler irrigation amount on the growth, grain yield, water consumption, and water use efficiency of winter wheat. Different treatments were installed, with the irrigation amounts expressed by the multiples of the evaporation (E) from a standard 20-cm diameter pan placed above winter wheat canopy. The grain yield was the highest in treatment 0.75 E in 2006-2007 and in treatment 0.625 E in 2007-2008. In treatments with irrigation amount less than 0.25 E, winter wheat growth was subjected to water stress, and the yield loss was larger than 25%. The water consumption of winter wheat in the two growth seasons was in the range of 219-486 mm, and increased with increasing irrigation amount. The relationships between the grain yield and the water consumption and water use efficiency could be described by quadratic function. Sprinkler irrigation with an amount of 0.50-0.75 E was recommended for the winter wheat growth after its turning green stage in Beijing area.

  4. The effects of payment instruments on charitable giving: Evidence from a field experiment

    NARCIS (Netherlands)

    Soetevent, A.R.

    2008-01-01

    This study reports on a door-to-door field experiment on the effects of introducing portable debit terminals for mobile payment authorization on the contributions to charity. About 4,500 households are approached, randomly divided in three experimental treatments, distinguished by the possibility

  5. Does the Unemployement Benefit Institution Affect the Productivity of Workers? Evidence from a Field Experiment

    NARCIS (Netherlands)

    Blanco, M.; Dalton, P.S.; Vargas, J.F.

    2013-01-01

    Abstract: We investigate whether and how the type of unemployment bene t institution affects productivity. We designed a field experiment to compare workers' productivity under a welfare system, where the unemployed receive an unconditional monetary transfer, with their productivity under a workfare

  6. The importance of holdup in contracting: Evidence from a field experiment

    NARCIS (Netherlands)

    Iyer, R.; Schoar, A.

    2008-01-01

    This paper explores how the relationship specificity of the investment affects the ex-ante structure of contracts and the ex-post resolution of an ensuing holdup problem. We set up a field experiment in the wholesale market for pens in India where we sent entrepreneurs as auditors to procure large

  7. Using Experiment and Computer Modeling to Determine the Off-Axis Magnetic Field of a Solenoid

    Science.gov (United States)

    Lietor-Santos, Juan Jose

    2014-01-01

    The study of the ideal solenoid is a common topic among introductory-based physics textbooks and a typical current arrangement in laboratory hands-on experiences where the magnetic field inside a solenoid is determined at different currents and at different distances from its center using a magnetic probe. It additionally provides a very simple…

  8. Estimating adhesive seed-dispersal distances : field experiments and correlated random walks

    NARCIS (Netherlands)

    Mouissie, AM; Lengkeek, W; van Diggelen, R

    1. In this study we aimed to estimate distance distributions of adhesively dispersed seeds and the factors that determine them. 2. Seed attachment and detachment were studied using field experiments with a real sheep, a sheep dummy and a cattle dummy. Seed-retention data were used in correlated

  9. An anaerobic field injection experiment in a landfill leachate plume (Grindsted, Denmark)

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Bjerg, Poul Løgstrup; Ludvigsen, L.

    1999-01-01

    Redox conditions may be environmental factors which affect the fate of the xenobiotic organic compounds. Therefore the redox conditions were characterized in an anaerobic, leachate-contaminated aquifer 15–60 m downgradient from the Grindsted Landfill, Denmark, where an field injection experiment ...

  10. Measurement of 3-Axis Magnetic Fields Induced by Current Wires Using a Smartphone in Magnetostatics Experiments

    Science.gov (United States)

    Setiawan, B.; Septianto, R. D.; Suhendra, D.; Iskandar, F.

    2017-01-01

    This paper describes the use of an inexpensive smartphone's magnetic sensor to measure magnetic field components (B[subscript x], B[subscript y] and B[subscript z]) induced by current wires in magnetostatic experiments. The variable parameters used to measure the magnetic sensor's capabilities were: the geometrical shapes of the wire, current…

  11. The Efficacy of Drama in Field Experience: A Qualitative Study Using MAXQDA

    Science.gov (United States)

    Elaldi, Senel; Yerliyurt, Nazli Sila

    2017-01-01

    This study attempted to evaluate the views of senior preservice preschool teachers on the efficacy of drama activities in their field experience in terms of the effect of students' learning, socialization, individual or group work skills and school connectedness and also disclosed the suggestions of senior preservice preschool teachers for faculty…

  12. News Media, Knowledge, and Political Interest: Evidence of a Dual Role From a Field Experiment

    NARCIS (Netherlands)

    Lecheler, S.; de Vreese, C.H.

    Political knowledge and political interest are generally positively influenced by news media exposure. Yet, at the same time, knowledge and interest are among the most important predictors of news media exposure in the first place. We conduct a field experiment (N = 393) as a test of this dual

  13. The role of status and leadership style in sales contests: A natural field experiment

    NARCIS (Netherlands)

    Verbeke, W.; Bagozzi, R.P.; Belschak, F.D.

    2016-01-01

    This paper addresses the question whether status alone, as compared to a combined financial/status incentive, is strong enough to motivate team members taking part in a retail sales contest to sell more goods to customers. Using a two-phase natural field experiment, we studied the impact of a sales

  14. Field experiments on seed dispersal by wind in ten umbelliferous species (Apiaceae)

    NARCIS (Netherlands)

    Jongejans, E.; Telenius, A.

    2001-01-01

    This report presents data from experiments on seed dispersal by wind for ten species of the family Apiaceae. Seed shadows were obtained in the field under natural conditions, using wind speeds between four and ten m/s. The flight of individual seeds was followed by eye, and seed shadows were

  15. Theory, Experimental Design, and Econometrics Are Complementary (And So Are Lab and Field Experiments)

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Lau, Morten; Rutström, E. Elisabet

    2015-01-01

    This book confronts and debates the issues faced by the growing field of experimental economics. For example, as experimental work attempts to test theory, it raises questions about the proper relationship between theory and experiments. As experimental results are used to inform policy, the util...

  16. The Preservice Teachers Are Watching: Framing and Reframing the Field Experience

    Science.gov (United States)

    Scherff, Lisa; Singer, Nancy Robb

    2012-01-01

    In this article we employ Sizers' (1999) school- and classroom-based lenses for observation and apply them to the events and interactions that teacher education students see during school-based field experiences. Our data include online reflections and discussions among 33 students enrolled in a teacher education program at a large, public…

  17. Reflecting on the Challenges of Informal Contexts: Early Field Experiences with Technology in Teacher Education

    Science.gov (United States)

    Lux, Nick; Obery, Amanda; Cornish, Jamie; Grimberg, Bruna Irene; Hartshorn, Anthony

    2017-01-01

    Early field experiences, or those that come early in a teacher's preparation before more formalized opportunities like practicum and student teaching, can provide a venue for pre service teachers to practice technology-specific instructional decision-making and reflective practice. Although research exists on the potential roles of field…

  18. Developing the Practice of Teacher Questioning through a K-2 Elementary Mathematics Field Experience

    Science.gov (United States)

    Schwartz, Catherine

    2015-01-01

    This article presents findings from research on a field experience designed to help elementary preservice teachers learn the practice of teacher questioning during formal and informal interviews to analyze student mathematical thinking in K-2 classrooms. The practice of teacher questioning is framed as choosing a mathematical goal, analyzing…

  19. Effectiveness of regulatory interventions on firm behavior : a randomized field experiment with e-commerce firms

    NARCIS (Netherlands)

    Huizingh, Eelko; Mulder, Machiel

    2014-01-01

    Economic regulators use a number of instruments to change the behavior of economic agents, but only limited evidence exists on the effectiveness of such regulatory interventions. We conduct a randomized field experiment to determine the effects of two interventions aimed at e-commerce firms by a

  20. Gaseous mercury fluxes from forest soils in response to forest harvesting intensity: A field manipulation experiment

    Science.gov (United States)

    M. Mazur; C.P.J. Mitchell; C.S. Eckley; S.L. Eggert; R.K. Kolka; S.D. Sebestyen; E.B. Swain

    2014-01-01

    Forest harvesting leads to changes in soil moisture, temperature and incident solar radiation, all strong environmental drivers of soil-air mercury (Hg) fluxes. Whether different forest harvesting practices significantly alter Hg fluxes from forest soils is unknown.We conducted a field-scale experiment in a northern Minnesota deciduous forest wherein gaseous Hg...

  1. Review of possible experiments in the eutectic growth and thermodiffusion fields

    International Nuclear Information System (INIS)

    Malmejac, Yves.

    1976-01-01

    The results now available from the SKYLAB and ASTP programmes give a clearer indication of the lines of the research to pursue in the years to come. The criteria necessary for the choice of experiments are analysed in the fields of eutectic solidification and diffusion along a temperature gradient in liquid alloys [fr

  2. The impact of gender diversity on the performance of business teams: evidence from a field experiment

    NARCIS (Netherlands)

    Hoogendoorn, S.; Oosterbeek, H.; van Praag, M.

    2013-01-01

    This paper reports on a field experiment conducted to estimate the impact of the share of women in business teams on their performance. Teams consisting of undergraduate students in business studies start up a venture as part of their curriculum. We manipulated the gender composition of teams and

  3. The impact of gender diversity on the performance of business teams: evidence from a field experiment.

    NARCIS (Netherlands)

    Hoogendoorn, S.; Oosterbeek, H.; van Praag, M.

    This paper reports about a field experiment conducted to estimate the impact of the share of women in business teams on their performance. Teams consisting of under-graduate students in business studies start up a venture as part of their curriculum. We manipulated the gender composition of teams

  4. The impact of gender diversity on the performance of business teams: evidence from a field experiment

    NARCIS (Netherlands)

    Hoogendoorn, S.; Oosterbeek, H.; van Praag, M.

    This paper reports about a field experiment conducted to estimate the impact of the share of women in business teams on their performance. Teams consisting of undergraduate students in business studies start up a venture as part of their curriculum. We manipulated the gender composition of teams and

  5. Rocket to Creativity: A Field Experience in Problem-Based and Project-Based Learning

    Science.gov (United States)

    Dole, Sharon F.; Bloom, Lisa A.; Doss, Kristy Kowalske

    2016-01-01

    This article reports the impact of a field experience in problem-based (PBL) and project-based learning (PjBL) on in-service teachers' conceptions of experiential learning. Participants had been enrolled in a hybrid class that included an online component in which they learned about PBL and PjBL, and an experiential component in which they…

  6. Fate of herbicides in a shallow aerobic aquifer: A continuous field injection experiment (Vejen,Denmark)

    DEFF Research Database (Denmark)

    Broholm, Mette; Rügge, K.; Tuxen, Nina

    2001-01-01

    A continuous, natural gradient, field injection experiment, involving six herbicides and a tracer, was performed in a shallow aerobic aquifer near Vejen, Denmark. Bentazone, ()-2-(4-chloro-2-methylphenoxy) propanoic acid (MCPP), dichlorprop, isoproturon, and the dichlobenil metabolite 2,6-dichlor...

  7. Developing the Effective Teaching Skills of Teacher Candidates during Early Field Experiences

    Science.gov (United States)

    Welsh, Kelly A.; Schaffer, Connie

    2017-01-01

    This study examined the development of effective teaching skills in teacher candidates in the context of early field experiences directly tied to a pedagogical course. Evidence from faculty instructors, mentor teachers, and teacher candidates suggests secondary education candidates were able to develop effective teaching skills related to…

  8. More than "Just" Changing Diapers: The Experiences of Preservice Early Childhood Teachers in Infant Field Placements

    Science.gov (United States)

    Beck, Lisa Marie Powell

    2010-01-01

    Despite the fact that early childhood preservice teachers are typically being prepared to work with children from birth through age 8, preservice field experiences with infants continue to be largely missing in early childhood teacher preparation programs Since the education and care of infants often takes place in vastly different settings than…

  9. High Speed Vessel Medical Limited Objective Experiment, Noise Assessment and Noise Reducing Stethoscope Field Test

    National Research Council Canada - National Science Library

    Russotti, Joseph S; Duplessis, Christopher

    2006-01-01

    .... This Medical Limited Objective Experiment (LOE) was valuable both to evaluate the noise environment in spaces not designed for habitation, and to simultaneously test a pre-production noise-reducing stethoscope. In controlled setting under operationally-relevant shipboard noise conditions in the field tests, the noise-reducing stethoscope proved to be significant, substantial improvement over a conventional sound-powered device.

  10. The effect of sowing strategy, row distance and mechanical weed control on weeds and yield in organic winter wheat

    OpenAIRE

    Rasmussen, Ilse A.

    2002-01-01

    A series of field experiments were carried out in winter wheat grown under organic conditions in Denmark on fields with different weed pressure. The treatments were sowing strategy (normal sowing time, late sowing and false seedbed), row distance (12 cm and 24 cm row distance) and weed control method (untreated, mechanical weed control (weed harrowing at 12 cm supplemented with row hoeing at 24 cm), and herbicide weed control). Weed biomass was largest at the normal sowing time and was reduce...

  11. Do terrorist attacks affect ethnic discrimination in the labour market? Evidence from two randomized field experiments.

    Science.gov (United States)

    Birkelund, Gunn Elisabeth; Chan, Tak Wing; Ugreninov, Elisabeth; Midtbøen, Arnfinn H; Rogstad, Jon

    2018-01-24

    Terrorist attacks are known to influence public opinion. But do they also change behaviour? We address this question by comparing the results of two identical randomized field experiments on ethnic discrimination in hiring that we conducted in Oslo. The first experiment was conducted before the 2011 terrorist attacks in Norway; the second experiment was conducted after the attacks. In both experiments, applicants with a typical Pakistani name were significantly less likely to get a job interview compared to those with a typical Norwegian name. But the ethnic gap in call-back rates were very similar in the two experiments. Thus, Pakistanis in Norway still experienced the same level of discrimination, despite claims that Norwegians have become more positive about migrants after the far-right, anti-migrant terrorist attacks of 2011. © London School of Economics and Political Science 2018.

  12. Laboratory experiments on plasma jets in a magnetic field using high-power lasers

    Science.gov (United States)

    Nishio, K.; Sakawa, Y.; Kuramitsu, Y.; Morita, T.; Ide, T.; Kuwada, M.; Koga, M.; Kato, T.; Norimatsu, T.; Gregory, C.; Woolsey, N.; Murphy, C.; Gregori, G.; Schaar, K.; Diziere, A.; Koenig, M.; Pelka, A.; Wang, S.; Dong, Q.; Li, Y.; Takabe, H.

    2013-11-01

    The experiments to simulate astrophysical jet generation are performed using Gekko XII (GXII) HIPER laser system at the Institute of Laser Engineering. In the experiments a fast plasma flow generated by shooting a CH plane (10 μm thickness) is observed at the rear side of the plane. By separating the focal spot of the main beams, a non-uniform plasma is generated. The non-uniform plasma flow in an external magnetic field (0.2˜0.3 T) perpendicular to the plasma is more collimated than that without the external magnetic field. The plasma β, the ratio between the plasma and magnetic pressure, is ≫ 1, and the magnetic Reynolds number is ˜150 in the collimated plasma. It is considered that the magnetic field is distorted by the plasma flow and enhances the jet collimation.

  13. Laboratory experiments on plasma jets in a magnetic field using high-power lasers

    International Nuclear Information System (INIS)

    Nishio, K.; Sakawa, Y.; Kuramitsu, Y.; Morita, T.; Ide, T.; Kuwada, M.; Koga, M.; Kato, T.; Norimatsu, T.; Gregory, C.; Woolsey, N.; Murphy, C.; Gregori, G.; Schaar, K.; Diziere, A.; Koenig, M.; Pelka, A.; Wang, S.; Dong, Q.; Li, Y.; Takabe, H.

    2013-01-01

    The experiments to simulate astrophysical jet generation are performed using Gekko XII (GXII) HIPER laser system at the Institute of Laser Engineering. In the experiments a fast plasma flow generated by shooting a CH plane (10 μm thickness) is observed at the rear side of the plane. By separating the focal spot of the main beams, a non-uniform plasma is generated. The non-uniform plasma flow in an external magnetic field (0.2∼0.3 T) perpendicular to the plasma is more collimated than that without the external magnetic field. The plasma β, the ratio between the plasma and magnetic pressure, is >>1, and the magnetic Reynolds number is ∼150 in the collimated plasma. It is considered that the magnetic field is distorted by the plasma flow and enhances the jet collimation. (authors)

  14. Measurement of 3-axis magnetic fields induced by current wires using a smartphone in magnetostatics experiments

    Science.gov (United States)

    Setiawan, B.; Septianto, R. D.; Suhendra, D.; Iskandar, F.

    2017-11-01

    This paper describes the use of an inexpensive smartphone’s magnetic sensor to measure magnetic field components (B x , B y and B z ) induced by current wires in magnetostatic experiments. The variable parameters used to measure the magnetic sensor’s capabilities were: the geometrical shapes of the wire, current flow, and the distance between wire and observation point. The experimental results are in good agreement with the results obtained from calculations using an analytical and numerical approach. In addition, the 2D vectors and magnitude of the magnetic field have been successfully illustrated. This study confirmed that the inexpensive smartphone’s magnetic sensor had a good ability to accurately measure the components of a magnetic field in a magnetostatic experiment, which is especially suitable for undergraduate students.

  15. A comparison of pine and spruce in recovery from winter stress; changes in recovery kinetics, and the abundance and phosphorylation status of photosynthetic proteins during winter.

    Science.gov (United States)

    Merry, Ryan; Jerrard, Jacob; Frebault, Julia; Verhoeven, Amy

    2017-09-01

    During winter evergreens maintain a sustained form of thermal energy dissipation that results in reduced photochemical efficiency measured using the chlorophyll fluorescence parameter Fv/Fm. Eastern white pine (Pinus strobus L.) and white spruce [Picea glauca (Moench) Voss] have been shown to differ in their rate of recovery of Fv/Fm from winter stress. The goal of this study was to monitor changes in photosynthetic protein abundance and phosphorylation status during winter recovery that accompany these functional changes. An additional goal was to determine whether light-dependent changes in light harvesting complex II (LHCII) phosphorylation occur during winter conditions. We used a combination of field measurements and recovery experiments to monitor chlorophyll fluorescence and photosynthetic protein content and phosphorylation status. We found that pine recovered three times more slowly than spruce, and that the kinetics of recovery in spruce included a rapid and slow component, while in pine there was only a rapid component to recovery. Both species retained relatively high amounts of the light harvesting protein Lhcb5 (CP26) and the PsbS protein during winter, suggesting a role for these proteins in sustained thermal dissipation. Both species maintained high phosphorylation of LHCII and the D1 protein in darkness during winter. Pine and spruce differed in the kinetics of the dephosphorylation of LHCII and D1 upon warming, suggesting the rate of dephosphorylation of LHCII and D1 may be important in the rapid component of recovery from winter stress. Finally, we demonstrated that light-dependent changes in LHII phosphorylation do not continue to occur on subzero winter days and that needles are maintained in a phosphorylation pattern consistent with the high light conditions to which those needles are exposed. Our results suggest a role for retained phosphorylation of both LHCII and D1 in maintenance of the photosynthetic machinery in a winter conformation

  16. Snowmelt and sublimation: field experiments and modelling in the High Atlas Mountains of Morocco

    Directory of Open Access Journals (Sweden)

    O. Schulz

    2004-01-01

    Full Text Available Snow in the High Atlas Mountains is a major source for freshwater renewal and for water availability in the semi-arid lowlands of south-eastern Morocco. Snowfall- and snow-ablation monitoring and modelling is important for estimating potential water delivery from the mountain water towers to the forelands. This study is part of GLOWA-IMPETUS, an integrated management project dealing with scarce water resources in West Africa. The Ameskar study area is located to the south of the High Atlas Mountains, in their rain shadow. As a part of the M’Goun river basin within the upper Drâa valley, the study area is characterised by high radiation inputs, low atmospheric humidity and long periods with sub-zero temperatures. Its altitude ranges between 2000 m and 4000 m, with dominant north- and south-facing slopes. Snowfall occurs mainly from November to April but even summit regions can become repeatedly devoid of snow cover. Snow cover maps for the M’Goun basin (1240 km2 are derived from calculations of NDSI (Normalized Difference Snow Index from MODIS satellite images and snow depth is monitored at four automatic weather stations between 2000–4000 m. Snowfall events are infrequent at lower altitudes. The presence of snow penitentes at altitudes above 3000 m indicates that snow sublimation is an important component of snow ablation. Snow ablation was modelled with the UEB Utah Energy Balance Model (Tarboton and Luce, 1996. This single layer, physically-based, point energy and mass balance model is driven by meteorological variables recorded at the automatic weather stations at Tounza (2960 m and Tichki (3260 m. Data from snow pillows at Tounza and Tichki are used to validate the model’s physical performance in terms of energy and water balances for a sequence of two snowfall events in the winter of 2003/4. First UEB modelling results show good overall performance and timing of snowmelt and sublimation compared to field investigations. Up to 44

  17. In pursuit of a science of agriculture: the role of statistics in field experiments.

    Science.gov (United States)

    Parolini, Giuditta

    2015-09-01

    Since the beginning of the twentieth century statistics has reshaped the experimental cultures of agricultural research taking part in the subtle dialectic between the epistemic and the material that is proper to experimental systems. This transformation has become especially relevant in field trials and the paper will examine the British agricultural institution, Rothamsted Experimental Station, where statistical methods nowadays popular in the planning and analysis of field experiments were developed in the 1920s. At Rothamsted statistics promoted randomisation over systematic arrangements, factorisation over one-question trials, and emphasised the importance of the experimental error in assessing field trials. These changes in methodology transformed also the material culture of agricultural science, and a new body, the Field Plots Committee, was created to manage the field research of the agricultural institution. Although successful, the vision of field experimentation proposed by the Rothamsted statisticians was not unproblematic. Experimental scientists closely linked to the farming community questioned it in favour of a field research that could be more easily understood by farmers. The clash between the two agendas reveals how the role attributed to statistics in field experimentation defined different pursuits of agricultural research, alternately conceived of as a scientists' science or as a farmers' science.

  18. Measurement and tricubic interpolation of the magnetic field for the OLYMPUS experiment

    International Nuclear Information System (INIS)

    Bernauer, J.C.; Diefenbach, J.; Elbakian, G.; Gavrilov, G.; Goerrissen, N.; Hasell, D.K.; Henderson, B.S.; Holler, Y.; Karyan, G.; Ludwig, J.; Marukyan, H.; Naryshkin, Y.; O'Connor, C.; Russell, R.L.; Schmidt, A.; Schneekloth, U.; Suvorov, K.; Veretennikov, D.

    2016-01-01

    The OLYMPUS experiment used a 0.3 T toroidal magnetic spectrometer to measure the momenta of outgoing charged particles. In order to accurately determine particle trajectories, knowledge of the magnetic field was needed throughout the spectrometer volume. For that purpose, the magnetic field was measured at over 36,000 positions using a three-dimensional Hall probe actuated by a system of translation tables. We used these field data to fit a numerical magnetic field model, which could be employed to calculate the magnetic field at any point in the spectrometer volume. Calculations with this model were computationally intensive; for analysis applications where speed was crucial, we pre-computed the magnetic field and its derivatives on an evenly spaced grid so that the field could be interpolated between grid points. We developed a spline-based interpolation scheme suitable for SIMD implementations, with a memory layout chosen to minimize space and optimize the cache behavior to quickly calculate field values. This scheme requires only one-eighth of the memory needed to store necessary coefficients compared with a previous scheme (Lekien and Marsden, 2005 [1]). This method was accurate for the vast majority of the spectrometer volume, though special fits and representations were needed to improve the accuracy close to the magnet coils and along the toroidal axis.

  19. Measurement and tricubic interpolation of the magnetic field for the OLYMPUS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bernauer, J.C. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA (United States); Diefenbach, J. [Hampton University, Hampton, VA (United States); Elbakian, G. [Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan (Armenia); Gavrilov, G. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Goerrissen, N. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Hasell, D.K.; Henderson, B.S. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA (United States); Holler, Y. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Karyan, G. [Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan (Armenia); Ludwig, J. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Marukyan, H. [Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan (Armenia); Naryshkin, Y. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); O' Connor, C.; Russell, R.L.; Schmidt, A. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA (United States); Schneekloth, U. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Suvorov, K.; Veretennikov, D. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation)

    2016-07-01

    The OLYMPUS experiment used a 0.3 T toroidal magnetic spectrometer to measure the momenta of outgoing charged particles. In order to accurately determine particle trajectories, knowledge of the magnetic field was needed throughout the spectrometer volume. For that purpose, the magnetic field was measured at over 36,000 positions using a three-dimensional Hall probe actuated by a system of translation tables. We used these field data to fit a numerical magnetic field model, which could be employed to calculate the magnetic field at any point in the spectrometer volume. Calculations with this model were computationally intensive; for analysis applications where speed was crucial, we pre-computed the magnetic field and its derivatives on an evenly spaced grid so that the field could be interpolated between grid points. We developed a spline-based interpolation scheme suitable for SIMD implementations, with a memory layout chosen to minimize space and optimize the cache behavior to quickly calculate field values. This scheme requires only one-eighth of the memory needed to store necessary coefficients compared with a previous scheme (Lekien and Marsden, 2005 [1]). This method was accurate for the vast majority of the spectrometer volume, though special fits and representations were needed to improve the accuracy close to the magnet coils and along the toroidal axis.

  20. Field experience and performance evaluation of a medium-concentration CPV system

    Science.gov (United States)

    Norton, Matthew; Bentley, Roger; Georghiou, George E.; Chonavel, Sylvain; De Mutiis, Alfredo

    2012-10-01

    With the aim of gaining experience and performance data from location with a harsh summer climate, a 70 X concentrating photovoltaic (CPV) system was installed in Janurary 2009 in Nicosia, Cyprus. The performance of this system has been monitored using regular current-voltage characterisations for three years. Over this period, the output of the system has remained fairly constant. Measured performance ratios varied from 0.79 to 0.86 in the winter, but fell to 0.64 over the year when left uncleaned. Operating cell temperatures were modeled and found to be similar to those of flat plate modules. The most significant causes of energy loss have been identified as originating from tracking issues and soiling. Losses due to soiling could account for a drop in output of 0.2% per day. When cleaned and properly oriented, the normalized output of the system has remained constant, suggesting that this particular design is tolerant to the physical strain of long-term outdoor exposure in harsh summer conditions. Regular cleaning and reliable tracker operation are shown to be essential for maximizing energy yield.

  1. Urban Field Experiences for Undergraduate Liberal Arts Students: Using Compromised Environments as Living Laboratories

    Science.gov (United States)

    MacAvoy, S. E.; Knee, K.

    2015-12-01

    While urban environments may lack the beauty of relatively pristine field sites, they can be used to deliver an effective demonstration of actual environmental damage. Students demanding applied field experiences from their undergraduate environmental science programs can be well served in urban settings. Here, we present strategies for integrating degraded urban systems into the undergraduate field experience. Urban locations provide an opportunity for a different type of local "field-work" than would otherwise be available. In the upper-level undergraduate Environmental Methods class, we relied on a National Park area located a 10-minute walk from campus for most field exercises. Activities included soil analysis, measuring stream flow and water quality parameters, dendrochronology, and aquatic microbe metabolism. In the non-majors class, we make use of our urban location to contrast water quality in parks and highly channelized urban streams. Students spend labs immersed in streams and wetlands heavily impacted by the urban runoff their city generates. Here we share lesson plans and budgets for field activities that can be completed during a class period of 2.5 hours with a $75 course fee, show how these activities help students gain quantitative competency.

  2. Polarization-preserving confocal microscope for optical experiments in a dilution refrigerator with high magnetic field.

    Science.gov (United States)

    Sladkov, Maksym; Bakker, M P; Chaubal, A U; Reuter, D; Wieck, A D; van der Wal, C H

    2011-04-01

    We present the design and operation of a fiber-based cryogenic confocal microscope. It is designed as a compact cold-finger that fits inside the bore of a superconducting magnet, and which is a modular unit that can be easily swapped between use in a dilution refrigerator and other cryostats. We aimed at application in quantum optical experiments with electron spins in semiconductors and the design has been optimized for driving with and detection of optical fields with well-defined polarizations. This was implemented with optical access via a polarization maintaining fiber together with Voigt geometry at the cold finger, which circumvents Faraday rotations in the optical components in high magnetic fields. Our unit is versatile for use in experiments that measure photoluminescence, reflection, or transmission, as we demonstrate with a quantum optical experiment with an ensemble of donor-bound electrons in a thin GaAs film. © 2011 American Institute of Physics

  3. The engineering approach to winter sports

    CERN Document Server

    Cheli, Federico; Maldifassi, Stefano; Melzi, Stefano; Sabbioni, Edoardo

    2016-01-01

    The Engineering Approach to Winter Sports presents the state-of-the-art research in the field of winter sports in a harmonized and comprehensive way for a diverse audience of engineers, equipment and facilities designers, and materials scientists. The book examines the physics and chemistry of snow and ice with particular focus on the interaction (friction) between sports equipment and snow/ice, how it is influenced by environmental factors, such as temperature and pressure, as well as by contaminants and how it can be modified through the use of ski waxes or the microtextures of blades or ski soles. The authors also cover, in turn, the different disciplines in winter sports:  skiing (both alpine and cross country), skating and jumping, bob sledding and skeleton, hockey and curling, with attention given to both equipment design and on the simulation of gesture and  track optimization.

  4. Editorial - The winter Atomiades

    CERN Multimedia

    Staff Association

    2011-01-01

    As we wrote in our previous editorial, the Staff Association gives direct support to sports events, such as the Atomiades, a section of the Association of Sports Communities of European Research Institutes, which brings together sportsmen and women from 38 European research centres in 13 countries (Austria, Belgium, Czech Republic, United Kingdom, Finland, France, Germany, Hungary, Italy, Luxemburg, the Netherlands, Russia, and Switzerland). The summer Atomiades take place between the months of June and September every three years. Thirteen such events have taken place since 1973, the last one in June 2009 in Berlin. As far as the winter Atomiades are concerned, also organized every three years, and alternating with the summer Atomiades, there have been eleven since 1981, the last one at the end of January this year in neighbouring France. The following article tells the wonderful adventure of the CERN staff who took part in this event. A positive outcome for CERN skiers at the winter Atomiades The 11t...

  5. The joys of mapping: qualitative insights into the student experience of a residential geoscience field course

    Science.gov (United States)

    Stokes, Alison

    2010-05-01

    Using a mixed-format survey instrument, Boyle et al. (2007) identify significant effects in the affective domain resulting from participation in residential fieldwork. These findings are echoed by Stokes & Boyle (2009) in a separate, more detailed, study into the experiences of geoscience students when learning geologic mapping. While providing a quantifiable measure of changes in the students' attitudes and feelings, however, these survey data provide limited information about the experiences that have resulted in these changes, or of the factors likely to have influenced them. In order to gain a deeper insight into the students' affective responses, the quantitative data collected during this study were supplemented with qualitative data from in-situ and group interviews, open (free-text) survey questions, and direct observation of fieldwork activities. This provided a richness and depth of information that could not be achieved from quantitative data alone, and thus afforded a greater understanding of the students' experiences of this particular field activity. The survey findings showed that positive feelings and attitudes present at the start of the mapping field course became reinforced, but closer scrutiny of the data revealed that over half of the student cohort (57%) embarked on the fieldwork with some degree of worry, concern, or anxiety. The qualitative data enabled the source of these negative feelings to be identified, and provided evidence that these were overcome as a result of participating in the fieldwork. Thematic content analysis of the data resulted in the emergence of ten major themes; these provided a clear indication of factors significant to the student experience, and of specific aspects of the field course likely to generate either positive or negative affective responses. Further, these data highlighted the complexity of the learning process, and demonstrated the extent to which experiences varied between individual students. The social

  6. Winter is losing its cool

    Science.gov (United States)

    Feng, S.

    2017-12-01

    Winter seasons have significant societal impacts across all sectors ranging from direct human health to ecosystems, transportation, and recreation. This study quantifies the severity of winter and its spatial-temporal variations using a newly developed winter severity index and daily temperature, snowfall and snow depth. The winter severity and the number of extreme winter days are decreasing across the global terrestrial areas during 1901-2015 except the southeast United States and isolated regions in the Southern Hemisphere. These changes are dominated by winter warming, while the changes in daily snowfall and snow depth played a secondary role. The simulations of multiple CMIP5 climate models can well capture the spatial and temporal variations of the observed changes in winter severity and extremes during 1951-2005. The models are consistent in projecting a future milder winter under various scenarios. The winter severity is projected to decrease 60-80% in the middle-latitude Northern Hemisphere under the business-as-usual scenario. The winter arrives later, ends earlier and the length of winter season will be notably shorter. The changes in harsh winter in the polar regions are weak, mainly because the warming leads to more snowfall in the high latitudes.

  7. On the relation between ionospheric winter anomalies and solar wind

    International Nuclear Information System (INIS)

    Rumi, G.C.

    2001-01-01

    There are two different winter anomalies. A small one that appears in connection with ionization at relatively low latitudes in the bottom of the D-region of the ionosphere. There, the electron densities in the winter happen to be less than should be expected. On the other hand, the classic winter anomaly is present when in the winter the upper D-region, again at relatively low latitudes, has more ionization than should be expected. Both these effects are due to the slant compression of the geomagnetic field produced by the solar wind in the wind in the winter season (which is, of course, the summer season when reference is made to events in the other hemisphere). It is shown that the small winter anomaly is a consequence of a hemispheric imbalance in the flux of galactic cosmic rays determined by the obliquely distorted geomagnetic field. It is shown that the standard winter anomaly can be ascribed to the influx of a super solar wind, which penetrates into the Earth's polar atmosphere down to E-region, heights and, duly concentrated through a funneling action at the winter pole of the distorted geomagnetic field, slows down the winter polar vortex. An equatorward motion of the polar air with its content of nitric oxide brings about the excess of ionization in the upper D-region at lower latitudes. The experimentally observed rhythmic recurrence of the upper winter anomaly is correlated to a possible rhythmic recurrence of the super solar wind. The actual detection of the upper winter anomaly could yield some information on the velocity of the basic solar wind. A by-product of the present analysis, the determination of Γ, the coefficient of collisional detachment of the electrons from the O 2 - ions, is presented in the Appendix

  8. From Formal Expertise to Co-expertise: Experience in the Field of Protection against Radiation

    International Nuclear Information System (INIS)

    Lochard, Jacques

    2002-01-01

    As a result of the growing difficulties confronting the heads of public and private high-risk activities, expertise practices have changed radically over the past years in the areas of risk assessment and management. In answer to the erosion of the credibility and legitimacy of traditional 'scientific' expertise, new forms of expertise based on citizen participation have emerged, particularly in fields involving public trust. The author's aim is to analyse the main changes in the field of radiological protection, on the basis of his 25 years of experience in the field. In conclusion, the author discusses the independence of expert assessment, an issue central to the present debate on the organization and practice of expertise in the field of high-risk activities

  9. Turbulent Dynamo Amplification of Magnetic Fields in Laser-Produced Plasmas: Simulations and Experiments

    Science.gov (United States)

    Tzeferacos, P.; Rigby, A.; Bott, A.; Bell, A.; Bingham, R.; Casner, A.; Cattaneo, F.; Churazov, E.; Forest, C.; Katz, J.; Koenig, M.; Li, C.-K.; Meinecke, J.; Petrasso, R.; Park, H.-S.; Remington, B.; Ross, J.; Ryutov, D.; Ryu, D.; Reville, B.; Miniati, F.; Schekochihin, A.; Froula, D.; Lamb, D.; Gregori, G.

    2017-10-01

    The universe is permeated by magnetic fields, with strengths ranging from a femtogauss in the voids between the filaments of galaxy clusters to several teragauss in black holes and neutron stars. The standard model for cosmological magnetic fields is the nonlinear amplification of seed fields via turbulent dynamo. We have conceived experiments to demonstrate and study the turbulent dynamo mechanism in the laboratory. Here, we describe the design of these experiments through large-scale 3D FLASH simulations on the Mira supercomputer at ANL, and the laser-driven experiments we conducted with the OMEGA laser at LLE. Our results indicate that turbulence is capable of rapidly amplifying seed fields to near equipartition with the turbulent fluid motions. This work was supported in part from the ERC (FP7/2007-2013, No. 256973 and 247039), and the U.S. DOE, Contract No. B591485 to LLNL, FWP 57789 to ANL, Grant No. DE-NA0002724 and DE-SC0016566 to the University of Chicago, and DE-AC02-06CH11357 to ANL.

  10. Rethermalization of a field-reversed configuration plasma in translation experiments

    International Nuclear Information System (INIS)

    Himura, H.; Okada, S.; Sugimoto, S.; Goto, S.

    1995-01-01

    A translation experiment of field-reversed configuration (FRC) plasma is performed on the FIX machine [Shiokawa and Goto, Phys. Fluids B 5, 534 (1993)]. The translated FRC bounces between magnetic mirror fields at both ends of a confinement region. The plasma loses some of its axial kinetic energy when it is reflected by the magnetic mirror field, and eventually settles down in the confinement region. In this reflection process, the plasma temperature rises significantly. Such plasma rethermalization has been observed in OCT-L1 experiments [Ito et al., Phys. Fluids 30, 168 (1987)], but rarely in FRX-C/T experiments [Rej et al., Phys. Fluids 29, 852 (1986)]. It is found that the rethermalization depends on the relation between the plasma temperature and the translation velocity. The rethermalization occurs only in the case where the translation velocity exceeds the sound velocity. This result implies the rethermalization is caused by a shock wave induced within the FRC when the plasma is reflected by the magnetic mirror field. copyright 1995 American Institute of Physics

  11. [Effects of different irrigation modes on winter wheat grain yield and water- and nitrogen use efficiency].

    Science.gov (United States)

    Men, Hong-wen; Zhang, Qiu; Dai, Xing-long; Cao, Qian; Wang, Cheng-yu; Zhou, Xiao-hu; He, Ming-rong

    2011-10-01

    Taking the widely planted winter wheat cultivar Tainong 18 as test material, a field experiment was conducted to study the effects of different irrigation modes on the winter wheat grain yield and water- and nitrogen use efficiency in drier year (2009-2010) in Tai' an City of Shandong Province, China. Five treatments were installed, i. e., irrigation before sowing (CK), irrigation before sowing and at jointing stage (W1), irrigation before sowing and at jointing stages and at over-wintering stage with alternative irrigation at milking stage (W2), irrigation before sowing and at jointing and flowering stages (optimized traditional irrigation mode, W3), and irrigation before sowing and at over-wintering, jointing, and milking stages (traditional irrigation mode, W4). The irrigation amount was 600 m3 hm(-2) one time. Under the condition of 119.7 mm precipitation in the winter wheat growth season, no significant difference was observed in the grain yield between treatments W2 and W4, but the water use efficiency was significantly higher in W2 than in W4. Comparing with treatment W3, treatments W2 and W4 had obviously higher grain yield, but the water use efficiency had no significant difference. The partial factor productivity from N fertilization was the highest in W2 and W4, and the NO3(-)-N accumulation amount in 0-100 cm soil layer at harvest was significantly higher in W2 than in W3 and W4, suggesting that W2 could reduce NO3(-)-N leaching loss. Under the conditions of our experiment, irrigation before sowing and jointing stages and at over-wintering stage with alternative irrigation at milking stage was the optimal irrigation mode in considering both the grain yield and the water- and nitrogen use efficiency.

  12. Comparative studies to evaluate the transferability of results from standardized laboratory experiments and ecosystem-compartments to the real field situation with the example of the degradation and leaching behaviour of metamitron and methabenzthiazuron in a degraded loess soil

    International Nuclear Information System (INIS)

    Kubiak, R.

    1986-04-01

    In order to validate data on residue situation and pesticide translocation in soil obtained in lysimeter studies, in comparison to field experiments with Goltix R and Tribunil R applied at rates of 5 and 10 or 2 and 4 kg/ha, respectively, [3- 14 C]metamitron and [carbonyl- 14 C]methabenzthiazuron have been sprayed in a preemergence treatment onto sugar beets and at the 3-4 leaf stage onto winter wheat growing in lysimeters. In addition 2 types of lysimeter were also compared: 1 m 2 surface area with 40-50 cm of packed top soil (Ap-horizon) and 0.5 m 2 surface area with 80 or 110 cm undisturbed soil profile of a degraded loess soil ('Parabraunerde') representing one of the most fertile soils in Germany, predominantly in agricultural use. All the requirements of soil cultivation, fertilization and additional plant protection treatments were conducted in full agreement with the field experiment. (orig./MG)

  13. Copper sulphate reduces the metabolic activity of Gammarus fossarum in laboratory and field experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schmidlin, Lara, E-mail: lara.schmidlin@unibas.ch; Fumetti, Stefanie von; Nagel, Peter

    2015-04-15

    Highlights: • Copper-contaminated food significantly reduces the ETS activity of G. fossarum. • The ETS and feeding activity of G. fossarum were significantly higher in the lab. • A combination of test chamber experiments in the laboratory and field is optimal. - Abstract: The specialised fauna of freshwater springs is affected by contamination of the water with xenobiotics from human activities in the surrounding landscape. We assessed the effects of exposure to toxins in laboratory and field experiments by using copper sulphate as a model substance and Gammarus fossarum Koch, 1836, as the model organism. This amphipod is a common representative of the European spring fauna and copper is a widespread contaminant, mainly from agricultural practice. The experiments were conducted in test chambers placed in flow channels and directly in a spring. The gammarids were fed with conditioned beech leaf discs, which had been exposed to a 0.8 mg Cu/L solution for 96 h. The feeding activity of the amphipods was quantified on the level of the organism; and the respiratory electron transport system (ETS) assay was conducted in order to determine changes on the cellular level in the test organisms. The results show that the feeding activity, when the leaf discs were contaminated with copper, was not significantly different from the control. The ETS activity of the gammarids, which had been feeding on the copper contaminated leaf discs was however significantly reduced. The results followed the same pattern for gammarids from both the laboratory and the spring. By conducting the experiments not only in a laboratory but also directly in a spring in the field, we took a crucial step towards a more realistic approach when examining environmental pollutants on an organism. Our findings demonstrate the importance of conducting experiments out in the field, in natural conditions, as well as in the laboratory.

  14. Enviromental behavior of sulfentrazone and fipronil in a Brazilian clayey latosol: field experiment and simulation

    Directory of Open Access Journals (Sweden)

    Rômulo Penna Scorza Júnior

    2014-10-01

    Full Text Available There has been an urgent need to assess pesticide environmental behavior under Brazilian field conditions and to evaluate the risks associated to its use in agriculture. Besides a qualitative and quantitative interpretation of field experiments to acquire understanding about pesticide environmental behaviour, field experiments are important to test pesticide fate models. Environmental behaviour of fipronil and sulfentrazone in a sugarcane area in Dourados, MS, was evaluated until 257 days after application. Moreover, the PEARL model was tested to simulate the fate of these two pesticides in the field. Soil samples for pesticide residue quantification and water content were taken at 0-10, 10-30, 30-50, 50-70 and 70-100 cm depth. There was a fast dissipation of both pesticides at soil surface within 15 days after application and their leaching was not beyond 30 cm depth. Dissipation and leaching satisfactory simulations for both pesticides were achieved only after calibration of half-life values or using a reduced initial dose. This study shows that fast dissipation of pesticides in the field can be an important process to consider when assessing the environmental behavior of pesticides in Brazil.

  15. Females and STEM: Determining the K-12 Experiences that Influenced Women to Pursue STEM Fields

    Science.gov (United States)

    Petersen, Anne Marie

    In the United States, careers in the fields of Science, Technology, Engineering, and Mathematics (STEM) are increasing yet there are not enough trained personnel to meet this demand. In addition, of those that seek to pursue STEM fields in the United States, only 26% are female. In order to increase the number of women seeking STEM based bachelor's degrees, K-12 education must provide a foundation that prepares students for entry into these fields. The purpose of this phenomenological study was to determine the perceived K-12 experiences that influenced females to pursue a STEM field. Twelve college juniors or seniors seeking a degree in Biology, Mathematics, or Physics were interviewed concerning their K-12 experiences. These interviews were analyzed and six themes emerged. Teacher passion and classroom characteristics such as incorporating challenging activities played a significant role in the females' decisions to enter STEM fields. Extra-curricular activities such as volunteer and mentor opportunities and the females' need to benefit others also influenced females in their career choice. Both the formal (within the school) and informal (outside of the traditional classroom) pipeline opportunities that these students encountered helped develop a sense of self-efficacy in science and mathematics; this self-efficacy enabled them to persist in pursuing these career fields. Several participants cited barriers that they encountered in K-12 education, but these barriers were primarily internal as they struggled with overcoming self-imposed obstacles in learning and being competitive in the mathematics and science classrooms. The experiences from these female students can be used by K-12 educators to prepare and encourage current female students to enter STEM occupations.

  16. CRISP. D3.3. Final report on field experiments and tests

    International Nuclear Information System (INIS)

    Warmer, C.J.; Kamphuis, I.G.; Gustavsson, R.; Andrieu, C.

    2006-06-01

    This document describes the high level results of the three field experiments and tests performed within the CRISP project. The aims of the document are: To give an account of the lessons learned from the experiments as they have been performed; To give recommendations for strategic use of intelligent ICT in high-DG power networks (thinking forward from our experience in the experiments); and To compile 'industrial guidelines and recommendations' for the strategic use of intelligent ICT for various operational aspects of high-DG power networks. These strategic recommendations will not only cover technology issues, but also business, economic, and market considerations. The role of utilities and third parties in utilising this new technology in this changing scene forms an important issue to be dealt with

  17. Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments

    Science.gov (United States)

    Cho, H. Jean; Jaffe, Peter R.; Smith, James A.

    1993-01-01

    This paper describes laboratory and field experiments which were conducted to study the dynamics of trichloroethylene (TCE) as it volatilized from contaminated groundwater and diffused in the presence of infiltrating water through the unsaturated soil zone to the land surface. The field experiments were conducted at the Picatinny Arsenal, which is part of the United States Geological Survey Toxic Substances Hydrology Program. In both laboratory and field settings the gas and water phase concentrations of TCE were not in equilibrium during infiltration. Gas-water mass transfer rate constants were calibrated to the experimental data using a model in which the water phase was treated as two phases: a mobile water phase and an immobile water phase. The mass transfer limitations of a volatile organic compound between the gas and liquid phases were described explicitly in the model. In the laboratory experiment the porous medium was nonsorbing, and water infiltration rates ranged from 0.076 to 0.28 cm h−1. In the field experiment the water infiltration rate was 0.34 cm h−1, and sorption onto the soil matrix was significant. The laboratory-calibrated gas-water mass transfer rate constant is 3.3×10−4 h−1 for an infiltration rate of 0.076 cm h−1 and 1.4×10−3 h−1 for an infiltration rate of 0.28 cm h−1. The overall mass transfer rate coefficients, incorporating the contribution of mass transfer between mobile and immobile water phases and the variation of interfacial area with moisture content, range from 3×10−4 h−1 to 1×10−2 h−1. A power law model relates the gas-water mass transfer rate constant to the infiltration rate and the fraction of the water phase which is mobile. It was found that the results from the laboratory experiments could not be extrapolated to the field. In order to simulate the field experiment the very slow desorption of TCE from the soil matrix was incorporated into the mathematical model. When desorption from the

  18. Critical fields and growth rates of the Tayler instability as probed by a columnar gallium experiment

    OpenAIRE

    Ruediger, Guenther; Gellert, Marcus; Schultz, Manfred; Strassmeier, Klaus G.; Stefani, Frank; Gundrum, Thomas; Seilmayer, Martin; Gerbeth, Gunter

    2012-01-01

    Many astrophysical phenomena (such as the slow rotation of neutron stars or the rigid rotation of the solar core) can be explained by the action of the Tayler instability of toroidal magnetic fields in the radiative zones of stars. In order to place the theory of this instability on a safe fundament it has been realized in a laboratory experiment measuring the critical field strength, the growth rates as well as the shape of the supercritical modes. A strong electrical current flows through a...

  19. Search for Chameleon Scalar Fields with the Axion Dark Matter Experiment

    International Nuclear Information System (INIS)

    Rybka, G.; Hotz, M.; Rosenberg, L. J; Asztalos, S. J.; Carosi, G.; Hagmann, C.; Kinion, D.; van Bibber, K.; Hoskins, J.; Martin, C.; Sikivie, P.; Tanner, D. B.; Bradley, R.; Clarke, J.

    2010-01-01

    Scalar fields with a 'chameleon' property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple weakly to the photon, they could be detectable through the afterglow effect of photon-chameleon-photon transitions. The ADMX experiment was used in the first chameleon search with a microwave cavity to set a new limit on scalar chameleon-photon coupling β γ excluding values between 2x10 9 and 5x10 14 for effective chameleon masses between 1.9510 and 1.9525 μeV.

  20. Note: versatile sample stick for neutron scattering experiments in high electric fields.

    Science.gov (United States)

    Bartkowiak, M; White, J S; Rønnow, H M; Prša, K

    2014-02-01

    We present a versatile high voltage sample stick that fits into all cryomagnets and standard cryostats at the Swiss Spallation Neutron Source, Paul Scherrer Institut, and which provides a low effort route to neutron scattering experiments that combine electric field with low temperature and magnetic field. The stick allows for voltages up to 5 kV and can be easily adapted for different scattering geometries. We discuss the design consideration and thermal behavior of the stick, and give one example to showcase the abilities of the device.

  1. The identifiable victim effect in charitable giving: evidence from a natural field experiment

    DEFF Research Database (Denmark)

    Lesner, Tine; Rasmussen, O. D.

    2014-01-01

    We design a natural field experiment to enhance our understanding of the role of the identifiable victim effect in charitable giving. Using direct mail solicitations to 25797 prior donors of a nonprofit charity, we tested the responsiveness of donors to make a contribution to either an identifiable...... or a statistical victim. Unlike much previous research, which has used only laboratory experiments, we find that the campaign letter focusing on one identifiable victim did not result in significantly larger donations than the campaign letter focusing on the statistical victim. In addition to the role...

  2. Comparison of laboratory and field experience of PWSCC in Alloy 182 weld metal

    Energy Technology Data Exchange (ETDEWEB)

    Scott, P.; Meunier, M.-C.; Steltzlen, F. [AREVA NP, Tour AREVA, Paris La Defense (France); Calonne, O.; Foucault, M. [AREVA NP, Centre Technique, Le Creusot Cedex (France); Combrade, P. [ACXCOR, Saint Etienne (France); Amzallag, C. [EDF, SEPTEN, Villeurbanne (France)

    2007-07-01

    Laboratory studies of stress corrosion cracking of the nickel base weld metal, Alloy 182, in simulated PWR primary water suggest similar resistance to crack initiation and somewhat enhanced propagation rates relative to wrought Alloy 600. By contrast, field experience of cracking in the primary circuits of PWRs shows in general much better performance for Alloy 182 relative to Alloy 600 than would be anticipated from laboratory studies. This paper endeavours to resolve this apparent conundrum. It draws on the conclusions of recent research that has focussed on the role of surface finish, particularly cold work and residual stresses resulting from different fabrication processes, on the risk of initiating IGSCC in nickel base alloys in PWR primary water. It also draws on field experience of stress corrosion cracking that highlights the important role of surface finish for crack initiation. (author)

  3. Emergency Response to Earthquake in Chile: Experience of a Cuban Field Hospital.

    Science.gov (United States)

    Pérez, Carlos R

    2015-07-01

    This paper presents the author's experiences in deploying and later establishing a Cuban field hospital in response to the major earthquake that struck Chile in February 2010. It also reveals the initial difficulties the medical team faced and how collaboration with local social, medical and military partners contributed to response efficiency, and highlights the importance of Cuba's international health cooperation, especially in emergency situations. Over 254 days, Cuban health professionals had 50,048 patient encounters (outpatient visits and hospitalizations), a daily average of 197. They performed 1778 surgeries (1427 major, 80.2% of total) and accumulated valuable experience in managing a field hospital in a disaster situation. KEYWORDS Earthquake, humanitarian aid, health care, emergency response, disaster medicine, logistics, Chile, Cuba.

  4. New indoor environment chambers and field experiment offices for research on human comfort, health and productivity

    DEFF Research Database (Denmark)

    Toftum, Jørn; Langkilde, Gunnar; Fanger, Povl Ole

    2004-01-01

    The article describes three new indoor environment chambers, a new laboratory for the study of air movement in spaces and five offices for controlled environment exposures of human subjects in field experiments at the International Centre for Indoor Environment and Energy, Technical University of...... of Denmark. Together with three older chambers, the Centre now has at its disposal 12 spaces for studying indoor environments and their impact on human comfort, health and productivity.......The article describes three new indoor environment chambers, a new laboratory for the study of air movement in spaces and five offices for controlled environment exposures of human subjects in field experiments at the International Centre for Indoor Environment and Energy, Technical University...

  5. Teacher Education Reform in Far East Russia: Integrating Field Experiences with Action Research

    Directory of Open Access Journals (Sweden)

    Grigory A. Kapranov

    2016-12-01

    Full Text Available In 2011, the Russian Far Eastern Federal University teacher education faculty redesigned field-experience practica to improve teacher candidates’ professional reflection, practical classroom instruction, and capacity for action research. For each academic year, faculty aspired to achieve these goals by collaborating to develop field experiences that differentiated mentoring of teacher candidates to fit with their professional goals and preparation levels. The purpose for this study is to investigate the effectiveness of this reform by comparing pre-reform senior theses to post-reform senior theses on a series of outcomes. Using a mixed-methods approach, findings indicate that post-reform teacher candidates outperformed pre-reform candidates on thesis quality. Specifically, post-reformed candidates were better able to make theoretical connections to their practice as evidenced by their action research topics and findings.

  6. Dataset on information strategies for energy conservation: A field experiment in India.

    Science.gov (United States)

    Chen, Victor L; Delmas, Magali A; Locke, Stephen L; Singh, Amarjeet

    2018-02-01

    The data presented in this article are related to the research article entitled: "Information strategies for energy conservation: a field experiment in India" (Chen et al., 2017) [1]. The availability of high-resolution electricity data offers benefits to both utilities and consumers to understand the dynamics of energy consumption for example, between billing periods or times of peak demand. However, few public datasets with high-temporal resolution have been available to researchers on electricity use, especially at the appliance-level. This article describes data collected in a residential field experiment for 19 apartments at an Indian faculty housing complex during the period from August 1, 2013 to May 12, 2014. The dataset includes detailed information about electricity consumption. It also includes information on apartment characteristics and hourly weather variation to enable further studies of energy performance. These data can be used by researchers as training datasets to evaluate electricity usage consumption.

  7. A case study of change in conceptions and practices of prospective science teachers during field experiences

    Science.gov (United States)

    Bradford, Cristine Schoneweg

    Field experiences are a pivotal component in the development of science pedagogy amongst future science teachers. This study sought to examine the ways in which prospective high school science teachers' conceptions of science pedagogy change, if at all, during the field experiences component of a science teacher preparation program. The following research questions guided this investigation of the experiences of two participating prospective science teachers: (1) What are the conceptions of teaching science held by participants? (2) How do these conceptions change as participants progress through pre-student teaching and student teaching? (3) What is the role of pre-student teaching and student teaching in the construction of these conceptions, from the perspective of the participants? (4) In what ways did the pre-student teaching and student teaching experiences constrain or support the development of conceptual change pedagogy among participants? This interpretive case study of participants' development in conceptions about science pedagogy was guided by principles of phenomenological inquiry. Primary sources of data were transcripts of semi-structured formal interviews with participants. Field notes from classroom observations and documents, such as journal entries and lesson plans, were used as supporting data. Data collection occurred during Fall 1995 and Spring 1996, as participants progressed through pre-student teaching and student teaching, respectively. The data were analyzed through an inductive procedure. There were two levels of data analysis. First, the data for each individual participant were analyzed; second, a cross-participant analysis was performed. The overarching assertion that emerged from the analysis was that 'the nature of the field experiences for these participants may have (inadvertently) rewarded the pursuit of technical proficiency at the expense of both critical reflection and development on issues related to participants

  8. Preparing beginning reading teachers: An experimental comparison of initial early literacy field experiences

    OpenAIRE

    Al Otaiba, Stephanie; Lake, Vickie E.; Greulich, Luana; Folsom, Jessica S.; Guidry, Lisa

    2012-01-01

    This randomized-control trial examined the learning of preservice teachers taking an initial Early Literacy course in an early childhood education program and of the kindergarten or first grade students they tutored in their field experience. Preservice teachers were randomly assigned to one of two tutoring programs: Book Buddies and Tutor Assisted Intensive Learning Strategies (TAILS), which provided identical meaning-focused instruction (shared book reading), but differed ...

  9. Understanding Peer Effects in Financial Decisions: Evidence from a Field Experiment

    OpenAIRE

    Leonardo Bursztyn; Florian Ederer; Bruno Ferman; Noam Yuchtman

    2012-01-01

    Using a high-stakes field experiment conducted with a financial brokerage, we implement a novel design to separately identify two channels of social influence in financial decisions, both widely studied theoretically. When someone purchases an asset, his peers may also want to purchase it, both because they learn from his choice ("social learning") and because his possession of the asset directly affects others' utility of owning the same asset ("social utility"). We find that both channels h...

  10. Detecting discrimination against homosexuals: Evidence from a field experiment on the Internet

    OpenAIRE

    Ahmed, Ali M.; Hammarstedt, Mats

    2007-01-01

    This paper presents the first field experiment studying discrimination against homosexuals. The study is conducted on the rental housing market in Sweden using the Internet as a research platform. Two fictitious couples, one heterosexual and one male homosexual, apply for vacant rental apartments advertised by landlords on the Internet. Our findings show that homosexual males are discriminated on the Swedish housing market, since the homosexual couple gets far fewer call backs, invitations to...

  11. Vertical sampling flights in support of the 1981 ASCOT cooling tower experiments: field effort and data

    Energy Technology Data Exchange (ETDEWEB)

    Gay, G.T.

    1982-03-01

    During the month of August 1981, three nights of experimental sampling of tracers released into the cooling tower plume of a geothermal power plant were conducted. In these experiments a tethered balloon was used to lift a payload so as to obtain vertical profiles of the cooling tower plume and the entrained tracers. A description of the equipment used, the field effort and the data acquired are presented here.

  12. Public Policy and Individual Labor Market Discrimination: An Artefactual Field Experiment in China

    OpenAIRE

    Uwe Dulleck; Jonas Fooken; Yumei He

    2012-01-01

    We study discrimination based on the hukou system, a policy segregating migrants and locals in urban China. We hired household aids as participants in our artefactual field experiment and use a gift exchange game to study labor market discrimination. We fi nd that social discrimination based on hukou status also implies individual level discrimination. To identify whether discrimination is statistical or taste-based we introduce the wage promising game, a gift exchange game with a cheap talk ...

  13. Observed chlorine concentrations during Jack Rabbit I and Lyme Bay field experiments

    Science.gov (United States)

    Hanna, Steven; Chang, Joseph; Huq, Pablo

    2016-01-01

    As part of planning for a series of field experiments where large quantities (up to 20 tons) of pressurized liquefied chlorine will be released, observations from previous chlorine field experiments are analyzed to estimate the ranges of chlorine concentrations expected at various downwind distances. In five field experiment days during the summer 2010 Jack Rabbit I (JR I) field trials, up to two tons of chlorine were released and concentrations were observed at distances, x, from 25 to 500 m. In the 1927 Lyme Bay (LB) experiments, there were four days of trials, where 3-10 tons of chlorine were released in about 15 min from the back of a ship. Concentrations were sampled at LB from four ships sailing across the cloud path at downwind distances in the range from about 350 to 3000 m. Thus, the distances from which JR I concentrations were available slightly overlapped the LB distances. One-minute arc-maximum chlorine concentrations, C (g/m3), were analyzed from four JR I trials and two LB trials. Normalized concentrations (Cu/Q) were plotted versus x (m), where u (m/s) is measured wind speed at heights of 2-10 m and Q (g/s) is continuous mass release rate. It is found that the JR I and LB Cu/Q observations smoothly merge with each other and fall along a line with approximate slope of -2 at distances beyond about 200 m (i.e., Cu/Q is proportional to x-2). At x < 200 m, where dense gas effects are more important, the slope is less (about -1.5). Most of the data points are within a factor of two of the "best-fit" line.

  14. Introducing Mobile Money in Rural Mozambique: Evidence from a Field Experiment*

    OpenAIRE

    Batista, Cátia; Vicente, Pedro C.

    2013-01-01

    The limitations of access to finance in Africa, together with the recent boom in cell phone use in that continent, created high expectations regarding the introduction of mobile money in many African countries. The success story of M-PESA in Kenya raised the bar further. We designed and conducted a field experiment to assess the impact of randomized mobile money dissemination in rural Mozambique. For this purpose we benefit from the fact that mobile money was only recently l...

  15. The importance of the toroidal magnetic field for the feasibility of a tokamak burning plasma experiment

    International Nuclear Information System (INIS)

    Mazzucato, E.

    2000-01-01

    The next step in the demonstration of the scientific feasibility of a tokamak fusion reactor is a DT burning plasma experiment for the study and control of self-heated plasmas. In this paper, the authors examine the role of the toroidal magnetic field on the confinement of a tokamak plasma in the ELMy H-mode regime--the operational regime foreseen for ITER

  16. Do Schools Discriminate Against Homosexual Parents? Evidence from an Internet Field Experiment

    OpenAIRE

    Meix Llop, Enric; Díaz Serrano, Lluís

    2015-01-01

    The recognition of homosexual rights is a controversial issue in many countries. Spain was the third country in the world (after Netherlands and Belgium) to introduce a law recognizing homosexual marriage and adoption of children. In this paper, we examine for the first time whether schools are more hesitant to give feedback to homosexual parents during children's pre-registration period in Spain. In order to do that, we designed an internet field experiment to be conducted in schools. We cre...

  17. Presentation and interpretation of field experiments of gaseous UF6 releases in the atmosphere

    International Nuclear Information System (INIS)

    Crabol, B.; Boulaud, D.; Deville-Cavelin, G.

    1992-01-01

    An experimental programme concerning the behaviour of UF 6 released in gaseous phase in the atmosphere has been conducted in the years 1986-1989 by the french Atomic Energy Commission and Eurodif. Three field tests have been performed on the CEA/CESTA experimental site. These experiments permitted to get informations about the kinetics of the hydrolysis reaction of the UF 6 , the behaviour of the hydrolysis products in the atmosphere and the granulometry of the solid particles

  18. Experiences of using mobile technologies and virtual field tours in Physical Geography: implications for hydrology education

    Directory of Open Access Journals (Sweden)

    D. G. Kingston

    2012-05-01

    Full Text Available Education in hydrology is changing rapidly due to diversification of students, emergent major scientific and practical challenges that our discipline must engage with, shifting pedagogic ideas and higher education environments, the need for students to develop new discipline specific and transferrable skills, and the advent of innovative technologies for learning and teaching. This paper focuses on new technologies in the context of learning and teaching in Physical Geography and reflects on the implications of our experiences for education in hydrology. We evaluate the experience of designing and trialling novel mobile technology-based field exercises and a virtual field tour for a Year 1 undergraduate Physical Geography module at a UK university. The new exercises are based on using and obtaining spatial data, operation of meteorological equipment (explained using an interactive DVD, and include introductions to global positioning systems (GPS and geographical information systems (GIS. The technology and exercises were well received in a pilot study and subsequent rolling-out to the full student cohort (∼150 students. A statistically significant improvement in marks was observed following the redesign. Although the students enjoyed using mobile technology, the increased interactivity and opportunity for peer learning were considered to be the primary benefits by students. This is reinforced further by student preference for the new interactive virtual field tour over the previous "show-and-tell" field exercise. Despite the new exercises having many advantages, exercise development was not trivial due to the high start-up costs, the need for provision of sufficient technical support and the relative difficulty of making year-to-year changes (to the virtual field tour in particular. Our experiences are highly relevant to the implementation of novel learning and teaching technologies in hydrology education.

  19. Migratory monarchs wintering in California experience low infection risk compared to monarchs breeding year-round on non-native milkweed.

    Science.gov (United States)

    Satterfield, Dara A; Villablanca, Francis X; Maerz, John C; Altizer, Sonia

    2016-08-01

    Long-distance migration can lower infection risk for animal populations by removing infected individuals during strenuous journeys, spatially separating susceptible age classes, or allowing migrants to periodically escape from contaminated habitats. Many seasonal migrations are changing due to human activities including climate change and habitat alteration. Moreover, for some migratory populations, sedentary behaviors are becoming more common as migrants abandon or shorten their journeys in response to supplemental feeding or warming temperatures. Exploring the consequences of reduced movement for host-parasite interactions is needed to predict future responses of animal pathogens to anthropogenic change. Monarch butterflies (Danaus plexippus) and their specialist protozoan parasite Ophryocystis elektroscirrha (OE) provide a model system for examining how long-distance migration affects infectious disease processes in a rapidly changing world. Annual monarch migration from eastern North America to Mexico is known to reduce protozoan infection prevalence, and more recent work suggests that monarchs that forego migration to breed year-round on non-native milkweeds in the southeastern and south central Unites States face extremely high risk of infection. Here, we examined the prevalence of OE infection from 2013 to 2016 in western North America, and compared monarchs exhibiting migratory behavior (overwintering annually along the California coast) with those that exhibit year-round breeding. Data from field collections and a joint citizen science program of Monarch Health and Monarch Alert showed that infection frequency was over nine times higher for monarchs sampled in gardens with year-round milkweed as compared to migratory monarchs sampled at overwintering sites. Results here underscore the importance of animal migrations for lowering infection risk and motivate future studies of pathogen transmission in migratory species affected by environmental change. © The

  20. Survey of academic field experiences (SAFE): trainees report harassment and assault.

    Science.gov (United States)

    Clancy, Kathryn B H; Nelson, Robin G; Rutherford, Julienne N; Hinde, Katie

    2014-01-01

    Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666) to characterize these experiences. Codes of conduct and sexual harassment policies were not regularly encountered by respondents, while harassment and assault were commonly experienced by respondents during trainee career stages. Women trainees were the primary targets; their perpetrators were predominantly senior to them professionally within the research team. Male trainees were more often targeted by their peers at the research site. Few respondents were aware of mechanisms to report incidents; most who did report were unsatisfied with the outcome. These findings suggest that policies emphasizing safety, inclusivity, and collegiality have the potential to improve field experiences of a diversity of researchers, especially during early career stages. These include better awareness of mechanisms for direct and oblique reporting of harassment and assault and, the implementation of productive response mechanisms when such behaviors are reported. Principal investigators are particularly well positioned to influence workplace culture at their field sites.

  1. Survey of academic field experiences (SAFE: trainees report harassment and assault.

    Directory of Open Access Journals (Sweden)

    Kathryn B H Clancy

    Full Text Available Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666 to characterize these experiences. Codes of conduct and sexual harassment policies were not regularly encountered by respondents, while harassment and assault were commonly experienced by respondents during trainee career stages. Women trainees were the primary targets; their perpetrators were predominantly senior to them professionally within the research team. Male trainees were more often targeted by their peers at the research site. Few respondents were aware of mechanisms to report incidents; most who did report were unsatisfied with the outcome. These findings suggest that policies emphasizing safety, inclusivity, and collegiality have the potential to improve field experiences of a diversity of researchers, especially during early career stages. These include better awareness of mechanisms for direct and oblique reporting of harassment and assault and, the implementation of productive response mechanisms when such behaviors are reported. Principal investigators are particularly well positioned to influence workplace culture at their field sites.

  2. Survey of Academic Field Experiences (SAFE): Trainees Report Harassment and Assault

    Science.gov (United States)

    Clancy, Kathryn B. H.; Nelson, Robin G.; Rutherford, Julienne N.; Hinde, Katie

    2014-01-01

    Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666) to characterize these experiences. Codes of conduct and sexual harassment policies were not regularly encountered by respondents, while harassment and assault were commonly experienced by respondents during trainee career stages. Women trainees were the primary targets; their perpetrators were predominantly senior to them professionally within the research team. Male trainees were more often targeted by their peers at the research site. Few respondents were aware of mechanisms to report incidents; most who did report were unsatisfied with the outcome. These findings suggest that policies emphasizing safety, inclusivity, and collegiality have the potential to improve field experiences of a diversity of researchers, especially during early career stages. These include better awareness of mechanisms for direct and oblique reporting of harassment and assault and, the implementation of productive response mechanisms when such behaviors are reported. Principal investigators are particularly well positioned to influence workplace culture at their field sites. PMID:25028932

  3. The magnetic field experiment onboard Equator-S and its scientific possibilities

    Directory of Open Access Journals (Sweden)

    K.-H. Fornacon

    1999-12-01

    Full Text Available The special feature of the ringcore fluxgate magnetometer on Equator-S is the high time and field resolution. The scientific aim of the experiment is the investigation of waves in the 10–100 picotesla range with a time resolution up to 64 Hz. The instrument characteristics and the influence of the spacecraft on the magnetic field measurement will be discussed. The work shows that the applied pre- and inflight calibration techniques are sufficient to suppress spacecraft interferences. The offset in spin axis direction was determined for the first time with an independent field measurement by the Equator-S Electron Drift Instrument. The data presented gives an impression of the accuracy of the measurement.Key words. Magnetospheric physics (instruments and techniques · Space plasma physics (instruments and techniques

  4. The International Heat Stress Genotype Experiment for Modeling Wheat Response to Heat: Field Experiments and AgMIP-Wheat Multi-Model Simulations

    Science.gov (United States)

    Martre, Pierre; Reynolds, Matthew P.; Asseng, Senthold; Ewert, Frank; Alderman, Phillip D.; Cammarano, Davide; Maiorano, Andrea; Ruane, Alexander C.; Aggarwal, Pramod K.; Anothai, Jakarat; hide

    2017-01-01

    The data set contains a portion of the International Heat Stress Genotype Experiment (IHSGE) data used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat crop models and quantify the impact of heat on global wheat yield productivity. It includes two spring wheat cultivars grown during two consecutive winter cropping cycles at hot, irrigated, and low latitude sites in Mexico (Ciudad Obregon and Tlaltizapan), Egypt (Aswan), India (Dharwar), the Sudan (Wad Medani), and Bangladesh (Dinajpur). Experiments in Mexico included normal (November-December) and late (January-March) sowing dates. Data include local daily weather data, soil characteristics and initial soil conditions, crop measurements (anthesis and maturity dates, anthesis and final total above ground biomass, final grain yields and yields components), and cultivar information. Simulations include both daily in-season and end-of-season results from 30 wheat models.

  5. The Hot Serial Cereal Experiment for modeling wheat response to temperature: field experiments and AgMIP-Wheat multi-model simulations

    NARCIS (Netherlands)

    Martre, P.; Kimball, B.A.; Ottman, M.J.; Wall, G.W.; White, J.; Asseng, S.; Ewert, F.; Cammarano, D.; Maiorano, Andrea; Supit, I.

    2017-01-01

    The data set reported here includes the part of a Hot Serial Cereal Experiment (HSC) experiment recently used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat models and quantify their response to temperature. The HSC experiment was conducted in an open-field in a semiarid

  6. ADX: a high field, high power density, Advanced Divertor test eXperiment

    Science.gov (United States)

    Vieira, R.; Labombard, B.; Marmar, E.; Irby, J.; Shiraiwa, S.; Terry, J.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; ADX Team

    2014-10-01

    The MIT PSFC and collaborators are proposing an advanced divertor experiment (ADX) - a tokamak specifically designed to address critical gaps in the world fusion research program on the pathway to FNSF/DEMO. This high field (6.5 tesla, 1.5 MA), high power density (P/S ~ 1.5 MW/m2) facility would utilize Alcator magnet technology to test innovative divertor concepts for next-step DT fusion devices (FNSF, DEMO) at reactor-level boundary plasma pressures and parallel heat flux densities while producing high performance core plasma conditions. The experimental platform would also test advanced lower hybrid current drive (LHCD) and ion-cyclotron range of frequency (ICRF) actuators and wave physics at the plasma densities and magnetic field strengths of a DEMO, with the unique ability to deploy launcher structures both on the low-magnetic-field side and the high-field side - a location where energetic plasma-material interactions can be controlled and wave physics is most favorable for efficient current drive, heating and flow drive. This innovative experiment would perform plasma science and technology R&D necessary to inform the conceptual development and accelerate the readiness-for-deployment of FNSF/DEMO - in a timely manner, on a cost-effective research platform. Supported by DE-FC02-99ER54512.

  7. Developing the Precision Magnetic Field for the E989 Muon g{2 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Matthias W. [Washington U., Seattle

    2017-01-01

    The experimental value of $(g\\hbox{--}2)_\\mu$ historically has been and contemporarily remains an important probe into the Standard Model and proposed extensions. Previous measurements of $(g\\hbox{--}2)_\\mu$ exhibit a persistent statistical tension with calculations using the Standard Model implying that the theory may be incomplete and constraining possible extensions. The Fermilab Muon g-2 experiment, E989, endeavors to increase the precision over previous experiments by a factor of four and probe more deeply into the tension with the Standard Model. The $(g\\hbox{--}2)_\\mu$ experimental implementation measures two spin precession frequencies defined by the magnetic field, proton precession and muon precession. The value of $(g\\hbox{--}2)_\\mu$ is derived from a relationship between the two frequencies. The precision of magnetic field measurements and the overall magnetic field uniformity achieved over the muon storage volume are then two undeniably important aspects of the e xperiment in minimizing uncertainty. The current thesis details the methods employed to achieve magnetic field goals and results of the effort.

  8. Wow, My Science Teacher Does Real Research! Engaging and Motivating Students Using Experiences from the Field

    Science.gov (United States)

    Scott, C.

    2013-12-01

    Students respond to personal connections. When K-12 science teachers are able to participate as field assistants on research projects, their students can benefit greatly from the stories, pictures, and video transmitted or brought back from the field. Teachers can translate and tailor their learning while in the field to the level of their students. Students are ';hooked' into science content by seeing their own teacher out there actually ';doing' science. The teacher is able to provide a direct content connection for the student, an avenue for understanding why ';learning this' is relevant and important. This presentation provides a case for why science teachers and researchers should collaborate as much as possible. The NSF funded PolarTREC program (Teachers and Researchers Exploring and Collaborating) is an excellent example of how to make this collaboration work. The presentation will also provide a look into how teachers can make an effective connection for their students between field science and classroom learning. Alaskan secondary science teacher Carol Scott spent a month at the Kevo Research Station in northern Finland in May/June 2013 as a PolarTREC teacher, and is translating this experience for students. She has also worked on an NSF Research Experience for Teachers grant in Prince William Sound, AK, and has successfully used this work to engage students in the classroom.

  9. Jet Grouting. Control of execution and result parameters. Test fields - Experience in Chile

    International Nuclear Information System (INIS)

    Ayarza, P. M.; Vukotic, G.

    2014-01-01

    This article emphasizes the importance of Test Fields in project that includes the Jet Grouting technique. In particular, the Chilean experience is analyzed, where the Jet Grouting was first introduced by Pilots Terratest S. A. in the year 2010, only, only in 2011 the first project using jet columns was constructed. The versatilely of this technique allows its use in a wide variety of projects, for example, soil capacity improvement, settlement control, reduction of soil permeability and other environmental applications. Currently, the most common applications are underpinning existing foundations, ground improvement, lateral support of excavations, hydraulic barriers, slope stabilization, liquefaction control, among others. The Jet Grouting is one of the most demanding soil improvement technique and requires excellence in designing and execution engineers and other involved specialist. It is therefore essential to ensure exhaustive control to the execution and final parameters, in order to check that the product- Jet Grouting element-have the design properties, and implement modifications if necessary. Many authors strongly advises that if there is no comparable experience and even if there is, a Test Field of Jet Grouting elements has to be executed in site. This field consists in a nearby area with similar geotechnical conditions of the project, where Jet Grouting test columns will be constructed. This Test Field will allow selecting the most effective execution parameters and verifying that the final product has he correct design properties. (Author)

  10. Magnetic field-aligned plasma expansion in critical ionization velocity space experiments

    International Nuclear Information System (INIS)

    Singh, N.

    1989-01-01

    Motivated by the recent Critical Ionization Velocity (CIV) experiments in space, the temporal evolution of a plasma cloud released in an ambient plasma is studied. Time-dependent Vlasov equations for both electrons and ions, along with the Poisson equation for the self-consistent electric field parallel to the ambient magnetic field, are solved. The initial cloud is assumed to consist of cold, warm, and hot electrons with temperatures T/sub c/ ≅ 0.2 eV, T/sub w/ ≅ 2 eV, and T/sub h/ ≅ 10 eV, respectively. It is found that the minor hot electrons escape the cloud, and their velocity distribution function shows the typical time-of-flight dispersion feature - that is, the larger the distance from the cloud, the larger is the average drift velocity of the escaping electrons. The major warm electrons expand along the magnetic field line with the corresponding ion-acoustic speed. The combined effect of the escaping hot electrons and the expanding warm ones sets up an electric potential structure which accelerates the ambient electrons into the cloud. Thus, the energy loss due to the electron escape is partly replenished. The electric field distribution in the potential structure depends on the stage of the evolution; before the rarefaction waves propagating from the edges of the cloud reach its center, the electric fields point into the cloud. After this stage the cloud divides into two subclouds, with each having their own bipolar electric fields. Effects of collisions on the evolution of plasma clouds are also discussed. The relevance of the results seen from the calculations are discussed in the context of recent space experiments on CIV

  11. Technetium-99 behavior in the terrestrial environment. Field observations and radiotracer experiments

    International Nuclear Information System (INIS)

    Tagami, Keiko

    2003-01-01

    Obtaining data on 99 Tc in the rice paddy field environment is important because Tc is a redox sensitive element. The behavior of Tc is expected to be different under upland field and rice paddy field conditions since the redox conditions in the soil environment differ. However, most of the data on the nuclide behavior in soil were obtained under upland field conditions. To understand the global fallout 99 Tc distributions in soil samples collected in Japan, a simple and rapid separation method was developed in order to determine low-levels of 99 Tc in soil samples by an inductively coupled plasma mass spectrometry. Also, radiotracer experiments using soils under aerobic and anaerobic conditions were carried out to clarify the Tc behavior under paddy field conditions. The results of determination of global fallout 99 Tc in Japanese soils indicated that the radionuclide had been accumulating in rice paddy fields. The mechanisms can be explained by the immobilization of Tc in soil under anaerobic conditions. From the radiotracer experiments, it was clear that under waterlogged conditions, the highly mobile TcO 4 - in soil was readily changed to other immobilized forms, such as TcO 2 , TcS 2 and organically bound forms. To this immobilization, the microbial activity seemed to have an important role in Tc sorption reactions. When the soil, which was once kept in anaerobic conditions, was air-dried again and kept in aerobic conditions, the chemical forms of immobilized Tc did not change remarkably. Interestingly, the similar Tc behavior was observed in a real wet forest near the Chernobyl Reactor. (author)

  12. Asian Tracer Experiment and Atmospheric Modeling (TEAM) Project: Draft Field Work Plan for the Asian Long-Range Tracer Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Allwine, K Jerry; Flaherty, Julia E.

    2007-08-01

    This report provides an experimental plan for a proposed Asian long-range tracer study as part of the international Tracer Experiment and Atmospheric Modeling (TEAM) Project. The TEAM partners are China, Japan, South Korea and the United States. Optimal times of year to conduct the study, meteorological measurements needed, proposed tracer release locations, proposed tracer sampling locations and the proposed durations of tracer releases and subsequent sampling are given. Also given are the activities necessary to prepare for the study and the schedule for completing the preparation activities leading to conducting the actual field operations. This report is intended to provide the TEAM members with the information necessary for planning and conducting the Asian long-range tracer study. The experimental plan is proposed, at this time, to describe the efforts necessary to conduct the Asian long-range tracer study, and the plan will undoubtedly be revised and refined as the planning goes forward over the next year.

  13. Interactions between crop biomass and development of foliar diseases in winter wheat and the potential to graduate the fungicide dose according to crop biomass

    DEFF Research Database (Denmark)

    Jensen, Peter Kryger; Jørgensen, Lise Nistrup

    2016-01-01

    Foliar pathogens such as Zymoseptoria tritici and Puccinia striiformis causing septoria leaf blotch and yellow rust respectively can cause serious yield reduction in winter wheat production, and control of the diseases often requires several fungicide applications during the growing season. Control...... and other foliar diseases in winter wheat was dependent on crop development and biomass level. If such a biomass dependent dose response was found it was further the purpose to evaluate the potential to optimize fungicide inputs in winter wheat crops applying a site-specific crop density dependent fungicide...... dose. The study was carried out investigating fungicide dose response controlling foliar diseases in winter wheat at three biomass densities obtained growing the crop at three nitrogen levels and using variable seed rates. Further the field experiments included three fungicide dose rates at each...

  14. Field Experiments of Pollination Ecology: The Case of Lycoris sanguinea var. sanguinea.

    Science.gov (United States)

    Yamaji, Futa; Ohsawa, Takeshi A

    2016-11-25

    Plant-pollinator interactions have been studied for approximately one hundred years. During that time, many field methods have been developed to clarify the pollination effectiveness of each pollinator for visited flowers. Pollinator observations have been one of the most common methods to identify pollinators, and bagging and cage experiments have been conducted to show the effectiveness of specific pollinators. In a previous study of Lycoris sanguinea var. sanguinea, its effective pollinators, the visitation frequencies of each floral visitor, and its reproductive strategies were not identified. This study reports the observation that small bees visited flowers that were partially opened (breaking buds). To the best of our knowledge, this phenomenon has not been reported previously. Further, this study investigates the hypothesis that small bees can pollinate at that flowering stage. This study demonstrates the basic methods of field experiments in pollination ecology using L. sanguinea var. sanguinea. Pollinator observations and digital video showed the visitation frequencies of each floral visitor. Bagging and cage experiments revealed that these flowers could be pollinated fully and that breaking-bud pollination could be important for the pollination of this plant species. The advantages and disadvantages of each method are discussed, and recent developments, including laboratory experiments, are described.

  15. Constraining chameleon field theories using the GammeV afterglow experiments

    International Nuclear Information System (INIS)

    Upadhye, A.; Steffen, J. H.; Weltman, A.

    2010-01-01

    The GammeV experiment has constrained the couplings of chameleon scalar fields to matter and photons. Here, we present a detailed calculation of the chameleon afterglow rate underlying these constraints. The dependence of GammeV constraints on various assumptions in the calculation is studied. We discuss the GammeV-CHameleon Afterglow SEarch, a second-generation GammeV experiment, which will improve upon GammeV in several major ways. Using our calculation of the chameleon afterglow rate, we forecast model-independent constraints achievable by GammeV-CHameleon Afterglow SEarch. We then apply these constraints to a variety of chameleon models, including quartic chameleons and chameleon dark energy models. The new experiment will be able to probe a large region of parameter space that is beyond the reach of current tests, such as fifth force searches, constraints on the dimming of distant astrophysical objects, and bounds on the variation of the fine structure constant.

  16. Constraining chameleon field theories using the GammeV afterglow experiments

    International Nuclear Information System (INIS)

    Upadhye, A.; Steffen, J.H.; Weltman, A.

    2009-01-01

    The GammeV experiment has constrained the couplings of chameleon scalar fields to matter and photons. Here we present a detailed calculation of the chameleon afterglow rate underlying these constraints. The dependence of GammeV constraints on various assumptions in the calculation is studied. We discuss GammeV-CHASE, a second-generation GammeV experiment, which will improve upon GammeV in several major ways. Using our calculation of the chameleon afterglow rate, we forecast model-independent constraints achievable by GammeV-CHASE. We then apply these constraints to a variety of chameleon models, including quartic chameleons and chameleon dark energy models. The new experiment will be able to probe a large region of parameter space that is beyond the reach of current tests, such as fifth force searches, constraints on the dimming of distant astrophysical objects, and bounds on the variation of the fine structure constant.

  17. U.S. Army RDECOM-ARDEC's results of the TG-53 experiment and field test

    Science.gov (United States)

    Desai, Sachi V.; Morcos, Amir

    2009-05-01

    Herein is described the U.S. Army RDECOM-ARDEC's purpose and series of activities conducted at the 2008 NATO SET-093 TG-53 experiment and field test. The overall purpose of the field test as stated by SET-093 panel was to provide a baseline test capable of providing relevant scenarios and data regarding a variety of impulsive generated acoustic events. As organized, the field experiment also allowed the room o study sensor interoperability across multiple platforms and multi-national users via the spider communication framework/reporting structure. This multinational network maintained by the host ETBS with a standardized messaging format with specific goals for each participating organization. ARDEC's role and purpose for the test was to provide situational awareness via the Spider and associated messaging format to the ETBS command center while continuing to gather unique acoustic data from various vantage points. ARDEC had several deliverables for the TG-53 field experiment derived from the mission and spirit of the field test. The most relevant deliverable was to demonstrate sensor interoperability via the Spider network and provide situational awareness by describing the said mortar/artillery events. The second purpose revolved around a relevant environment algorithm validation of the muzzle blast discrimination for future UGS transition in particular the UTAMS II. The algorithm validation information remained internal to the specific data acquisition system and not broadcasted out on the Spider network. The TG-53 field experiments provided the added opportunity to further test and refine the algorithm based on the discrete wavelet transform (DWT) and multiresolution analysis. These techniques are used to classify and reliably discriminates between launch and impact artillery and/or mortar events via acoustic signals produced during detonation. Distinct characteristics are found within the acoustic signatures since impact events emphasize concussive and

  18. Lessons in collaboration and effective field research from the Appalachian Headwaters Research Experience for Undergraduates Program

    Science.gov (United States)

    Jones, A. L.; Fox, J.; Wilder, M. S.

    2009-12-01

    In the summer of 2009, the authors launched year one of a three-year National Science Foundation-funded Research Experience for Undergraduates entitled "Carbon Storage and Headwater Health in the Appalachian Headwaters." Eight undergraduates selected from a nationally competitive field of more than 60 applicants participated in the ten-week field- and laboratory-based program along with three middle- and high-school teachers. Each student developed and completed an independent research project related to coal mining’s impact on soil organic carbon and sediment transport processes. Specifically, they used isotope ratio mass spectrometry to measure the carbon and nitrogen stable isotopic signature of soils and sediments in the Appalachian headwater landscapes and first order streams of Kentucky's southeastern coalfields. Among the program's innovative features was its fundamentally collaborative nature--which was represented in several ways. First, the background of the three program leaders was very different: an environmental planner with an academic background in land use planning and administration (Jones); a civil engineer trained in biogeochemistry and watershed modeling (Fox); and an environmental educator experienced in both formal and nonformal educator training and certification (Wilder). The program was also a collaboration between a Carnegie 1 research-oriented institution and an undergraduate/ teaching -focused regional comprehensive university. Finally, the participants themselves represented a diversity of disciplines and institutional backgrounds--including biology, geology, chemistry, environmental science and civil engineering. The Research Experience for Teachers component was another innovative program element. The teachers participated in all field and laboratory research activities during the first six weeks, then developed a unit of study for their own classrooms to be implemented during the current school year. In addition to the six

  19. INTERRUPTED IN-SITU COMPRESSIVE DEFORMATION EXPERIMENTS ON MMC FOAMS IN AN XCT: EXPERIMENTS AND ESTIMATION OF DISPLACEMENT FIELDS

    Directory of Open Access Journals (Sweden)

    Katharina Losch

    2014-05-01

    Full Text Available The mechanical properties of a metal-matrix composite foam are investigated by interrupted in-situ compressive deformation experiments within an X-ray computed tomography device (XCT. Each in-situ experiment generates a sequence of reconstructed 3D images of the foam microstructure. From these data, the deformation field is estimated by registring the images corresponding to three consecutive steps. To this end, the generic registration framework of the itk software suite is exploited and combined with several image preprocessing steps. Both segmented (binary images having just two grey values for foreground (strut structure and background (pore space and the result of the Euclidean distance transform (EDT on pore space and solid phase are used. The estimation quality is evaluated based on a sequence of synthetic data sets, where the foam’s microstructure is modelled by a random Laguerre tessellation. For large deformations, a combination of non-rigid registration for the EDT images and partwise-rigid registration on strongly deformed regions of the binary images, yields surprisingly small estimation errors.

  20. Laboratory experiments on the magnetic field and neutral density limits on CIV interaction

    International Nuclear Information System (INIS)

    Axnaes, I.; Brenning, N.

    1990-03-01

    Laboratory experiments are reported which determine the magnetic field and neutral density limit for Critical Ionization Velocity (CIV) interaction in the impact configuration. A combination of microwave interferometry and spectroscopy has been used to measure how the electron energy distribution varies with the neutral density and the magnetic field strength. The efficiency of the CIV process is evaluated in terms of the efficiency factor η of energy transfer to the electron. This efficiency is studied as function of the ratio V A /V 0 between the Alfven velocity and the plasma stream velocity and the ratio ν i /ω gi between the ionization frequency and the ion gyro frequency. With other parameters kept constant, V A /V 0 is proportional to the square root of the magnetic field, while ν i /ω gi is proportional to the neutral density. We have found that these two dimensionless parameters are coupled in such a fashion that a stronger magnetic field can compensate for a lower neutral density. For our strongest magnetic field, corresponding to V A /V 0 = 4, CIV interaction is found to occur for a comparatively low value ν i /ω gi ∼ 0.1. For V A /V 0 = 1, we found a clear absence of CIV interaction even for ν i /ω gi approaching unity. (authors)

  1. Catheter visualisation in MR tomography: first animal experimental experiences with field inhomogeneity catheters

    International Nuclear Information System (INIS)

    Adam, G.; Glowinski, A.; Neuerburg, J.; Buecker, A.; Vaals, J.J. van; Hurtak, W.; Guenther, R.W.

    1997-01-01

    Purpose: To assess the feasibility of a new developed field inhomogeneity catheter for interventional MR imaging in vivo. Materials and methods: Three different prototypes of a field inhomogeneity catheter were investigated in 6 pigs. The catheters were introduced in Seldinger technique via the femoral vessels over a guide wire on an interventional MR system (Philips Gyroscan NT combined with a C-arm fluoroscopy unit [Philips BV 212[). Catheters were placed in veins and arteries. The catheter position was controlled by a fast gradient echo sequence (Turbo Field Echo [TEF[). Results: Catheters were introduced over a guide wire without complications in all cases. Using the field inhomogeneity concept, catheters were easily visualised in the inferior vena cava and the aorta by the fast gradient echo technique on MR in all cases. Although aortic branches were successfully cannulated, the catheters were not displayed by the TFE technique due to the complex and tortuous anatomy. All animals survived the experiments without complications. Conclusion: MR guided visualisation of a field inhomogeneity catheter is a simple concept which can be realised on each MR scanner and may allow intravascular MR guided interventions in future. (orig.) [de

  2. ANOMALIES IN THE APPLIED MAGNETIC FIELDS ON DIII-D AND THEIR IMPLICATIONS FOR THE UNDERSTANDING OF STABILITY EXPERIMENTS

    International Nuclear Information System (INIS)

    LUXON, J.L; SCHAFFER, M.J; JACKSON, G.L; LEUER, J.A; NAGY, A; SCOVILLE, J.T; STRAIT, E.J

    2003-01-01

    Small non-axisymmetric magnetic fields are known to cause serious loss of stability in tokamaks leading to loss of confinement and abrupt termination of plasma current (disruptions). The best known examples are the locked mode and the resistive wall mode. Understanding of the underlying field anomalies (departures in the hardware-related fields from ideal toroidal and poloidal fields on a single axis) and the interaction of the plasma with them is crucial to tokamak development. Results of both locked mode experiments and resistive wall mode experiments done in DIII-D tokamak plasmas have been interpreted to indicate the presence of a significant anomalous field. New measurements of the magnetic field anomalies of the hardware systems have been made on DIII-D. The measured field anomalies due to the plasma shaping coils in DIII-D are smaller than previously reported. Additional evaluations of systematic errors have been made. New measurements of the anomalous fields of the ohmic heating and toroidal coils have been added. Such detailed in situ measurements of the fields of a tokamak are unique. The anomalous fields from all of the coils are one third of the values indicated from the stability experiments. These results indicate limitations in the understanding of the interaction of the plasma with the external field. They indicate that it may not be possible to deduce the anomalous fields in a tokamak from plasma experiments and that we may not have the basis needed to project the error field requirements of future tokamaks

  3. Anomalies in the applied magnetic fields in DIII-D and their implications for the understanding of stability experiments

    Energy Technology Data Exchange (ETDEWEB)

    Luxon, J. L.; Schaffer, M. J.; Jackson, G. L.; Leuer, J. A.; Nagy, A.; Scoville, J. T.; Strait, E. J.

    2003-12-01

    Small non-axisymmetric magnetic fields are known to cause serious loss of stability in tokamaks leading to loss of confinement and abrupt termination of plasma current (disruptions). The best known examples are the locked mode and the resistive wall mode. Understanding of the underlying field anomalies (departures in the hardware-related fields from ideal toroidal and poloidal fields on a single axis) and the interaction of the plasma with them is crucial to tokamak development. Results of both locked mode experiments and resistive wall mode experiments done in DIII-D tokamak plasmas have been interpreted to indicate the presence of a significant anomalous field. New measurements of the magnetic field anomalies of the hardware systems have been made on DIII-D. The measured field anomalies due to the plasma shaping coils in DIII-D are smaller than previously reported. Additional evaluations of systematic errors have been made. New measurements of the anomalous fields of the ohmic heating and toroidal coils have been added. Such detailed in situ measurements of the fields of a tokamak are unique. The anomalous fields from all of the coils are one third of the values indicated from the stability experiments. These results indicate limitations in the understanding of the interaction of the plasma with the external field. They indicate that it may not be possible to deduce the anomalous fields in a tokamak from plasma experiments and that we may not have the basis needed to project the error field requirements of future tokamaks.

  4. Field work in geography. Region with experience in socio-environmental conflicts

    Directory of Open Access Journals (Sweden)

    Beatriz Ensabella

    2016-07-01

    Full Text Available This article emphasizes the importance of the geographical field work in a region with socio-environmental conflict, such us the problem with water in Sierras Chicas, Cordoba. The main focus is a pedagogical experience, the Socio-Communal Practice (SCP, performed by professors, students and assistants of the subject Rural Geography, of the Bachelor’s in Geography course of studies of the Philosophy and Humanity School (PHS, in the city of La Granja, in Colón, Córdoba. The SCP is an experience that makes the students approach the social field of the territory conflicts. It is an activity that goes beyond the extension project, since it involves all the students doing the subject. And it is also a way to combine -in our case, from the geographic work- the teaching, investigation and extension functions typical of the university students. Through the SCP, we aim to make the Rural Geography students approach the field work, with local social organizations that deeply know the problems of their cities and that work together with our investigation group. In addition, this contact together with the individual thoughts, the group discussion and the debates between the university students, will broaden, in the whole society, the knowledge about the reality in which they live and with which they struggle. This article starts by defining what it is understood by SCP. Then, taking into account our practice, we develop what we consider to be the two logics that support the field work. One refers to the building of knowledge and to the different ways of learning and knowing. The other is related to the understanding of the socio-territory conflict in the area where the practice will be done: the Mesa del Agua and La Granja environment. We include a section about the description of the experience and its results, and we conclude with some reflections made taking into account the continuity of the practice

  5. Depletion of rice as food of waterfowl wintering in the Mississippi Alluvial Valley

    Science.gov (United States)

    Greer, Danielle M.; Dugger, Bruce D.; Reinecke, Kenneth J.; Petrie, Mark J.

    2009-01-01

    Waterfowl habitat conservation strategies in the Mississippi Alluvial Valley (MAV) and several other wintering areas assume carrying capacity is limited by available food, and increasing food resources is an effective conservation goal. Because existing research on winter food abundance and depletion is insufficient to test this hypothesis, we used harvested rice fields as model foraging habitats to determine if waste rice seed is depleted before spring migration. We sampled rice fields (n = 39 [winter 2000-2001], n = 69 [2001-2002]) to estimate seed mass when waterfowl arrived in late autumn and departed in late winter. We also placed exclosures in subsets of fields in autumn (n = 8 [2000-2001], n = 20 [2001-2002]) and compared seed mass inside and outside exclosures in late winter to estimate rice depletion attributable to waterfowl and other processes. Finally, we used an experiment to determine if the extent of rice depletion differed among fields of varying initial abundance and if the seed mass at which waterfowl ceased foraging or abandoned fields differed from a hypothesized giving-up value of 50 kg/ha. Mean seed mass was greater in late autumn 2000 than 2001 (127.0 vs. 83.9 kg/ha; P = 0.018) but decreased more during winter 2000-2001 than 2001-2002 (91.3 vs. 55.7 kg/ha) and did not differ at the end of winter (35.8 vs. 28.3 kg/ha; P = 0.651). Assuming equal loss to deterioration inside and outside exclosures, we estimated waterfowl consumed 61.3 kg/ha (48.3%) of rice present in late autumn 2000 and 21.1 kg/ha (25.1%) in 2001. When we manipulated late-autumn rice abundance, mean giving-up mass of rice seed was similar among treatments (48.7 kg/ha; P = 0.205) and did not differ from 50 kg/ha (P = 0.726). We integrated results by constructing scenarios in which waterfowl consumed rice at different times in winter, consumption and deterioration were competing risks, and consumption occurred only above 50 kg/ha. Results indicated waterfowl likely consumed

  6. Earthworms influenced by reduced tillage, conventional tillage and energy forest in Swedish agricultural field experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lagerloef, Jan (SLU, Department of Ecology, Swedish University of Agricultural Sciences, Uppsala (Sweden)), Email: Jan.Lagerlof@ekol.slu.se; Paalsson, Olof; Arvidsson, Johan (SLU, Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala (Sweden))

    2012-03-15

    We compared earthworm density, depth distribution and species composition in three soil cultivation experiments including the treatments ploughless tillage and mouldboard ploughing. Sampling was done in September 2005 and for one experiment also in 1994. By yearly sampling 1995-2005, earthworms in an energy forest of Salix viminalis were compared with those in an adjacent arable field. Sampling method was digging of soil blocks and hand sorting and formalin sampling in one cultivation experiment. Both methods were used in the energy forest and arable land comparison. In two soil cultivation experiments, highest abundances or biomass were found in ploughless tillage. Earthworm density was higher in the upper 10 cm, especially in the ploughless tillage. Earthworm density was significantly higher in the energy forest than in the arable field. Formalin sampling revealed c. 36% of the earthworm numbers found by digging in the energy forest and gave almost no earthworms in the arable field. In all treatments with soil cultivation, species living and feeding in the rhizosphere and soil dominated. One such species, Allolobophora chlorotica, was more abundant under mouldboard ploughing than ploughless tillage. Lumbricus terrestris, browsing on the surface and producing deep vertical burrows, was more common in the ploughless tillage. Species living and feeding close to the soil surface were almost only found in the energy forest, which had not been soil cultivated since 1984. The findings support earlier studies pointing out possibilities to encourage earthworms by reduced soil cultivation. This is one of the first published studies that followed earthworm populations in an energy forest plantation during several years. Explanation of earthworm reactions to management and environmental impacts should be done with consideration of the ecology of species or species groups. Earthworm sampling by formalin must always be interpreted with caution and calibrated by digging and

  7. 78 FR 63069 - Special Regulations; Areas of the National Park System; Yellowstone National Park; Winter Use

    Science.gov (United States)

    2013-10-23

    ... National Park; Winter Use AGENCY: National Park Service, Interior. ACTION: Final rule. SUMMARY: The... to experience the unique winter resources and values at Yellowstone National Park. This rule includes... cleaner and quieter than what has been allowed during the previous four winter seasons, reward oversnow...

  8. 78 FR 22470 - Special Regulations; Areas of the National Park System; Yellowstone National Park; Winter Use

    Science.gov (United States)

    2013-04-16

    ... National Park; Winter Use AGENCY: National Park Service, Interior. ACTION: Proposed rule. SUMMARY: The... experience the unique winter resources and values at Yellowstone National Park. This rule includes provisions... cleaner and quieter than what has been authorized during the previous four winter seasons, reward oversnow...

  9. The responses of microbial temperature relationships to seasonal change and winter warming in a temperate grassland.

    Science.gov (United States)

    Birgander, Johanna; Olsson, Pål Axel; Rousk, Johannes

    2018-01-18

    Microorganisms dominate the decomposition of organic matter and their activities are strongly influenced by temperature. As the carbon (C) flux from soil to the atmosphere due to microbial activity is substantial, understanding temperature relationships of microbial processes is critical. It has been shown that microbial temperature relationships in soil correlate with the climate, and microorganisms in field experiments become more warm-tolerant in response to chronic warming. It is also known that microbial temperature relationships reflect the seasons in aquatic ecosystems, but to date this has not been investigated in soil. Although climate change predictions suggest that temperatures will be mostly affected during winter in temperate ecosystems, no assessments exist of the responses of microbial temperature relationships to winter warming. We investigated the responses of the temperature relationships of bacterial growth, fungal growth, and respiration in a temperate grassland to seasonal change, and to 2 years' winter warming. The warming treatments increased winter soil temperatures by 5-6°C, corresponding to 3°C warming of the mean annual temperature. Microbial temperature relationships and temperature sensitivities (Q 10 ) could be accurately established, but did not respond to winter warming or to seasonal temperature change, despite significant shifts in the microbial community structure. The lack of response to winter warming that we demonstrate, and the strong response to chronic warming treatments previously shown, together suggest that it is the peak annual soil temperature that influences the microbial temperature relationships, and that temperatures during colder seasons will have little impact. Thus, mean annual temperatures are poor predictors for microbial temperature relationships. Instead, the intensity of summer heat-spells in temperate systems is likely to shape the microbial temperature relationships that govern the soil-atmosphere C

  10. Scoping a field experiment: error diagnostics of TRMM precipitation radar estimates in complex terrain as a basis for IPHEx2014

    Science.gov (United States)

    Duan, Y.; Wilson, A. M.; Barros, A. P.

    2015-03-01

    A diagnostic analysis of the space-time structure of error in quantitative precipitation estimates (QPEs) from the precipitation radar (PR) on the Tropical Rainfall Measurement Mission (TRMM) satellite is presented here in preparation for the Integrated Precipitation and Hydrology Experiment (IPHEx) in 2014. IPHEx is the first NASA ground-validation field campaign after the launch of the Global Precipitation Measurement (GPM) satellite. In anticipation of GPM, a science-grade high-density raingauge network was deployed at mid to high elevations in the southern Appalachian Mountains, USA, since 2007. This network allows for direct comparison between ground-based measurements from raingauges and satellite-based QPE (specifically, PR 2A25 Version 7 using 5 years of data 2008-2013). Case studies were conducted to characterize the vertical profiles of reflectivity and rain rate retrievals associated with large discrepancies with respect to ground measurements. The spatial and temporal distribution of detection errors (false alarm, FA; missed detection, MD) and magnitude errors (underestimation, UND; overestimation, OVR) for stratiform and convective precipitation are examined in detail toward elucidating the physical basis of retrieval error. The diagnostic error analysis reveals that detection errors are linked to persistent stratiform light rainfall in the southern Appalachians, which explains the high occurrence of FAs throughout the year, as well as the diurnal MD maximum at midday in the cold season (fall and winter) and especially in the inner region. Although UND dominates the error budget, underestimation of heavy rainfall conditions accounts for less than 20% of the total, consistent with regional hydrometeorology. The 2A25 V7 product underestimates low-level orographic enhancement of rainfall associated with fog, cap clouds and cloud to cloud feeder-seeder interactions over ridges, and overestimates light rainfall in the valleys by large amounts, though this

  11. Measurements for winter road maintenance

    OpenAIRE

    Riehm, Mats

    2012-01-01

    Winter road maintenance activities are crucial for maintaining the accessibility and traffic safety of the road network at northerly latitudes during winter. Common winter road maintenance activities include snow ploughing and the use of anti-icing agents (e.g. road salt, NaCl). Since the local weather is decisive in creating an increased risk of slippery conditions, understanding the link between local weather and conditions at the road surface is critically important. Sensors are commonly i...

  12. Science objectives of the magnetic field experiment onboard Aditya-L1 spacecraft

    Science.gov (United States)

    Yadav, Vipin K.; Srivastava, Nandita; Ghosh, S. S.; Srikar, P. T.; Subhalakshmi, Krishnamoorthy

    2018-01-01

    The Aditya-L1 is first Indian solar mission scheduled to be placed in a halo orbit around the first Lagrangian point (L1) of Sun-Earth system in the year 2018-19. The approved scientific payloads onboard Aditya-L1 spacecraft includes a Fluxgate Digital Magnetometer (FGM) to measure the local magnetic field which is necessary to supplement the outcome of other scientific experiments onboard. The in-situ vector magnetic field data at L1 is essential for better understanding of the data provided by the particle and plasma analysis experiments, onboard Aditya-L1 mission. Also, the dynamics of Coronal Mass Ejections (CMEs) can be better understood with the help of in-situ magnetic field data at the L1 point region. This data will also serve as crucial input for the short lead-time space weather forecasting models. The proposed FGM is a dual range magnetic sensor on a 6 m long boom mounted on the Sun viewing panel deck and configured to deploy along the negative roll direction of the spacecraft. Two sets of sensors (tri-axial each) are proposed to be mounted, one at the tip of boom (6 m from the spacecraft) and other, midway (3 m from the spacecraft). The main science objective of this experiment is to measure the magnitude and nature of the interplanetary magnetic field (IMF) locally and to study the disturbed magnetic conditions and extreme solar events by detecting the CME from Sun as a transient event. The proposed secondary science objectives are to study the impact of interplanetary structures and shock solar wind interaction on geo-space environment and to detect low frequency plasma waves emanating from the solar corona at L1 point. This will provide a better understanding on how the Sun affects interplanetary space. In this paper, we shall give the main scientific objectives of the magnetic field experiment and brief technical details of the FGM onboard Aditya-1 spacecraft.

  13. Vegetation Water Content Mapping in a Diverse Agricultural Landscape: National Airborne Field Experiment 2006

    Science.gov (United States)

    Cosh, Michael H.; Jing Tao; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2011-01-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE 06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE 06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/sq m. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy. Keywords: Vegetation, field experimentation, thematic mapper, NDWI, agriculture.

  14. Evidence of lead biomagnification in invertebrate predators from laboratory and field experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rubio-Franchini, Isidoro [Departamento de Quimica, Centro de Ciencias Basicas, Universidad Autonoma de Aguascalientes, Avenida Universidad 940, CP 20131 Aguascalientes (Mexico); Rico-Martinez, Roberto, E-mail: rrico@correo.uaa.mx [Departamento de Quimica, Centro de Ciencias Basicas, Universidad Autonoma de Aguascalientes, Avenida Universidad 940, CP 20131 Aguascalientes (Mexico)

    2011-07-15

    This report includes atomic absorption data from water column, elutriates and zooplankton that demonstrate that lead biomagnifies at El Niagara reservoir, Mexico. Results include field data (bioaccumulation factors) (BAFs) and laboratory data (bioconcentration factors) (BCFs). Two findings: high BAFs for invertebrate predator like Acanthocyclops robustus, Asplanchna brightwellii, Culex sp. larvae, and Hyalella azteca, compared to grazer species Moina micrura and Simocephalus vetulus; low BCF's found for some predators, suggested that lead biomagnifications were taking place. The presence of Moina micrura in the gut of Asplanchna allowed us to design experiments where A. brightwellii was fed lead-exposed M. micrura neonates. The BAF of Asplanchna was 123,684, BCF was 490. Asplanchna individuals fed exposed Moina had 13.31 times more lead than Asplanchna individuals just exposed 48-h to lead, confirming that lead biomagnification occurs. Results of two fish species showed no lead biomagnification, suggesting that lead biomagnification might be restricted to invertebrate predators. - Highlights: > Study shows lead biomagnification evidence in reservoirs where top predators are invertebrates. > Study discusses why in previous studies lead biomagnifications were not detected. > Evidence of biomagnification comes from field and laboratory studies. - This study shows evidence (from field and laboratory experiments) of lead biomagnification in a freshwater reservoir where the main predators are invertebrates.

  15. Overview of long-term field experiments in Germany - metadata visualization

    Science.gov (United States)

    Muqit Zoarder, Md Abdul; Heinrich, Uwe; Svoboda, Nikolai; Grosse, Meike; Hierold, Wilfried

    2017-04-01

    BonaRes ("soil as a sustainable resource for the bioeconomy") is conducting to collect data and metadata of agricultural long-term field experiments (LTFE) of Germany. It is funded by the German Federal Ministry of Education and Research (BMBF) under the umbrella of the National Research Strategy BioEconomy 2030. BonaRes consists of ten interdisciplinary research project consortia and the 'BonaRes - Centre for Soil Research'. BonaRes Data Centre is responsible for collecting all LTFE data and regarding metadata into an enterprise database upon higher level of security and visualization of the data and metadata through data portal. In the frame of the BonaRes project, we are compiling an overview of long-term field experiments in Germany that is based on a literature review, the results of the online survey and direct contacts with LTFE operators. Information about research topic, contact person, website, experiment setup and analyzed parameters are collected. Based on the collected LTFE data, an enterprise geodatabase is developed and a GIS-based web-information system about LTFE in Germany is also settled. Various aspects of the LTFE, like experiment type, land-use type, agricultural category and duration of experiment, are presented in thematic maps. This information system is dynamically linked to the database, which means changes in the data directly affect the presentation. An easy data searching option using LTFE name, -location or -operators and the dynamic layer selection ensure a user-friendly web application. Dispersion and visualization of the overlapping LTFE points on the overview map are also challenging and we make it automatized at very zoom level which is also a consistent part of this application. The application provides both, spatial location and meta-information of LTFEs, which is backed-up by an enterprise geodatabase, GIS server for hosting map services and Java script API for web application development.

  16. Early Pottery Making in Northern Coastal Peru. Part II: Field Firing Experiments

    International Nuclear Information System (INIS)

    Shimada, I.; Goldstein, D.; Sosa, J.; Wagner, U.

    2003-01-01

    We present data from three seasons of experimental field work designed to recreate ancient Andean coastal ceramic firing techniques. Based on the recent discovery of two different archaeological ceramic production sites in the La Leche river valley of northern coastal Peru, the opportunity arose to apply Moessbauer spectroscopy and other analytical methods to reconstruct ancient firing procedures. Two sets of firings took place in 1993 and 1997 in Batan Grande using a partially restored Formative kiln from about 800 BC, local hardwood and cow dung as fuel. A third experiment followed in 2000 after the discovery of a Middle Sican ceramics workshop in use between ca. AD 950 and 1050 at Huaca Sialupe, where an exact replica of an ancient kiln was built from local clay, and fired with local wood and cow dung. Additionally, inverted urns found at Huaca Sialupe were tested for their potential use as furnaces for metal working. Moessbauer spectroscopy was used to compare the physical and chemical state of specimens produced in the field experiments with ancient ceramics and with specimens produced in controlled laboratory experiments.

  17. Early Pottery Making in Northern Coastal Peru. Part II: Field Firing Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, I.; Goldstein, D. [Southern Illinois University (United States); Sosa, J. [Potter in the City of Chulcanas (Peru); Wagner, U. [Technische Universitaet Muenchen, Physik-Department E15 (Germany)

    2003-09-15

    We present data from three seasons of experimental field work designed to recreate ancient Andean coastal ceramic firing techniques. Based on the recent discovery of two different archaeological ceramic production sites in the La Leche river valley of northern coastal Peru, the opportunity arose to apply Moessbauer spectroscopy and other analytical methods to reconstruct ancient firing procedures. Two sets of firings took place in 1993 and 1997 in Batan Grande using a partially restored Formative kiln from about 800 BC, local hardwood and cow dung as fuel. A third experiment followed in 2000 after the discovery of a Middle Sican ceramics workshop in use between ca. AD 950 and 1050 at Huaca Sialupe, where an exact replica of an ancient kiln was built from local clay, and fired with local wood and cow dung. Additionally, inverted urns found at Huaca Sialupe were tested for their potential use as furnaces for metal working. Moessbauer spectroscopy was used to compare the physical and chemical state of specimens produced in the field experiments with ancient ceramics and with specimens produced in controlled laboratory experiments.

  18. Computer Simulation and Field Experiment for Downlink Multiuser MIMO in Mobile WiMAX System.

    Science.gov (United States)

    Yamaguchi, Kazuhiro; Nagahashi, Takaharu; Akiyama, Takuya; Matsue, Hideaki; Uekado, Kunio; Namera, Takakazu; Fukui, Hiroshi; Nanamatsu, Satoshi

    2015-01-01

    The transmission performance for a downlink mobile WiMAX system with multiuser multiple-input multiple-output (MU-MIMO) systems in a computer simulation and field experiment is described. In computer simulation, a MU-MIMO transmission system can be realized by using the block diagonalization (BD) algorithm, and each user can receive signals without any signal interference from other users. The bit error rate (BER) performance and channel capacity in accordance with modulation schemes and the number of streams were simulated in a spatially correlated multipath fading environment. Furthermore, we propose a method for evaluating the transmission performance for this downlink mobile WiMAX system in this environment by using the computer simulation. In the field experiment, the received power and downlink throughput in the UDP layer were measured on an experimental mobile WiMAX system developed in Azumino City in Japan. In comparison with the simulated and experimented results, the measured maximum throughput performance in the downlink had almost the same performance as the simulated throughput. It was confirmed that the experimental mobile WiMAX system for MU-MIMO transmission successfully increased the total channel capacity of the system.

  19. Colloid Facilitated Transport of Radioactive Cations in the Vadose Zone: Field Experiments Oak Ridge

    Energy Technology Data Exchange (ETDEWEB)

    James E. Saiers

    2012-09-20

    The overarching goal of this study was to improve understanding of colloid-facilitated transport of radioactive cations through unsaturated soils and sediments. We conducted a suite of laboratory experiments and field experiments on the vadose-zone transport of colloids, organic matter, and associated contaminants of interest to the U.S. Department of Energy (DOE). The laboratory and field experiments, together with transport modeling, were designed to accomplish the following detailed objectives: 1. Evaluation of the relative importance of inorganic colloids and organic matter to the facilitation of radioactive cation transport in the vadose zone; 2. Assessment of the role of adsorption and desorption kinetics in the facilitated transport of radioactive cations in the vadose zone; 3. Examination of the effects of rainfall and infiltration dynamics and in the facilitated transport of radioactive cations through the vadose zone; 4. Exploration of the role of soil heterogeneity and preferential flow paths (e.g., macropores) on the facilitated transport of radioactive cations in the vadose zone; 5. Development of a mathematical model of facilitated transport of contaminants in the vadose zone that accurately incorporates pore-scale and column-scale processes with the practicality of predicting transport with readily available parameters.

  20. Remarks relating to field experiments to measure the wet scavenging of tracer aerosols

    International Nuclear Information System (INIS)

    Stensland, G.J.

    1977-12-01

    An important question is whether or not the wet deposition of debris from a single (or multiple) airburst of a nuclear device poses a significant hazard to people on the ground. To answer this question for various scenarios, a basic understanding of the aerosol attachment rates to cloud water and raindrops is needed. The attachment rates can then be incorporated into the cloud physics scavenging models to make intelligent assessments. In order to gain an initial impression as to the importance (order of magnitude) of the wet scavenging effects and to provide the data to validate the cloud scavenging models, tracer release field experiments are useful and necessary. The major purpose of this report is to address questions related to the operation and interpretation of such field tracer efforts and in particular to consider the results from the August 3, 1972, Battelle Northwest Laboratory tracer experiment in St. Louis. The Battelle experiment involved the release of several aerosol tracers at 10,000 to 13,000 feet, near rain clouds, and the measurement of the resulting tracer in the rain collected at the ground level sampling sites

  1. Winter fuels report

    Energy Technology Data Exchange (ETDEWEB)

    1990-11-29

    The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and state and local governments on the following topics: distillate fuel oil net production, imports and stocks for all PADD's and product supplied on a US level; propane net product supplied on a US level; propane net production, imports and stocks for Petroleum Administration for Defense Districts (PADD) I, II, and III; natural gas supply and disposition and underground storage for the United States and consumption for all PADD's; residential and wholesale pricing data for propane and heating oil for those states participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the United States and selected cities; and US total heating degree-days by city. 27 figs, 12 tabs.

  2. Winter fuels report

    Energy Technology Data Exchange (ETDEWEB)

    1995-02-17

    The Winter Fuels Report is intended to provide consise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: Distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; Natural gas supply and disposition and underground storage for the US and consumption for all PADD`s as well as selected National average prices; Residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; Crude oil and petroleum price comparisons for the US and selected cities; and A 6-10 Day and 30-Day outlook for temperature and precipitation and US total heating degree days by city.

  3. Winter fuels report

    International Nuclear Information System (INIS)

    1995-01-01

    The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD's I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD's, as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 day, 30-Day, and 90-Day outlook for temperature and precipitation and US total heating degree-days by city

  4. Thermal Field Indicator for Identifying Active Faults and its Instability From Laboratory Experiments

    Science.gov (United States)

    Ma, J.; Liu, L.; Liu, P.; Ma, S.

    2007-12-01

    The relationship between the thermal filed and strain field during deformation of faults is the physical basis to clarify whether satellite infrared information and the ground temperature field can be used to study fault activity. This study attempts to discuss these problems by experiments in the laboratory. The two-direction servo-control system was used to load on the samples with compressional and extensional en echelon faults. An infrared thermal image system and a contact-type thermometer recorded synchronously variations of the bright temperature field of infrared radiation and temperature field during deformation of the rock specimens. A digital CCD camera and a soft ware based on the digital speckle correlation method (DSCM) was utilized to capture images and to analyze them, yielding processes of displacement and strain fields. The experimental result shows as follows: 1 The temperature is highest at the jog area of the compressional en echelon faults, whereas that is lowest at the extensional en echelon faults prior to failure of the jog area. The record by DSCM displays that the mean strain of the jog area is largest for the compressional en echelon faults, while that is smallest for the extensional en echelon faults. These mean that the temperature field has clear responses to the opposite stress states at the jog areas of two kinds of en echelon faults, providing an indicator for determining whether the fault segment has slid. 2 The en echelon faults experience two deformation stages from stress building up and fault propagating at the jog area to unstable sliding along the fault. Correspondingly the mechanism of heating-up is turned from strain heating into frictional heating. Three kinds of phenomena have been observed at the jog area and its vicinity during the stage of transformation. They are temperature drop, fast fluctuation of temperature, and pulses of temperature rising, respectively. Mechanism of these phenomena is discussed. 3 These

  5. Field experiment provides ground truth for surface nuclear magnetic resonance measurement

    Science.gov (United States)

    Knight, R.; Grunewald, E.; Irons, T.; Dlubac, K.; Song, Y.; Bachman, H.N.; Grau, B.; Walsh, D.; Abraham, J.D.; Cannia, J.

    2012-01-01

    The need for sustainable management of fresh water resources is one of the great challenges of the 21st century. Since most of the planet's liquid fresh water exists as groundwater, it is essential to develop non-invasive geophysical techniques to characterize groundwater aquifers. A field experiment was conducted in the High Plains Aquifer, central United States, to explore the mechanisms governing the non-invasive Surface NMR (SNMR) technology. We acquired both SNMR data and logging NMR data at a field site, along with lithology information from drill cuttings. This allowed us to directly compare the NMR relaxation parameter measured during logging,T2, to the relaxation parameter T2* measured using the SNMR method. The latter can be affected by inhomogeneity in the magnetic field, thus obscuring the link between the NMR relaxation parameter and the hydraulic conductivity of the geologic material. When the logging T2data were transformed to pseudo-T2* data, by accounting for inhomogeneity in the magnetic field and instrument dead time, we found good agreement with T2* obtained from the SNMR measurement. These results, combined with the additional information about lithology at the site, allowed us to delineate the physical mechanisms governing the SNMR measurement. Such understanding is a critical step in developing SNMR as a reliable geophysical method for the assessment of groundwater resources.

  6. Interaction of Fast Ions with Global Plasma Modes in the C-2 Field Reversed Configuration Experiment

    Science.gov (United States)

    Smirnov, Artem; Dettrick, Sean; Clary, Ryan; Korepanov, Sergey; Thompson, Matthew; Trask, Erik; Tuszewski, Michel

    2012-10-01

    A high-confinement operating regime [1] with plasma lifetimes significantly exceeding past empirical scaling laws was recently obtained by combining plasma gun edge biasing and tangential Neutral Beam Injection (NBI) in the C-2 field-reversed configuration (FRC) experiment [2, 3]. We present experimental and computational results on the interaction of fast ions with the n=2 rotational and n=1 wobble modes in the C-2 FRC. It is found that the n=2 mode is similar to quadrupole magnetic fields in its detrimental effect on the fast ion transport due to symmetry breaking. The plasma gun generates an inward radial electric field, thus stabilizing the n=2 rotational instability without applying the quadrupole magnetic fields. The resultant FRCs are nearly axisymmetric, which enables fast ion confinement. The NBI further suppresses the n=2 mode, improves the plasma confinement characteristics, and increases the plasma configuration lifetime [4]. The n=1 wobble mode has relatively little effect on the fast ion transport, likely due to the approximate axisymmetry about the displaced plasma column. [4pt] [1] M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012).[0pt] [2] M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010).[0pt] [3] H.Y. Guo et al., Phys. Plasmas 18, 056110 (2011).[0pt] [4] M. Tuszewski et al., Phys. Plasmas 19, 056108 (2012)

  7. Information barriers and social stratification in higher education: evidence from a field experiment.

    Science.gov (United States)

    Abbiati, Giovanni; Argentin, Gianluca; Barone, Carlo; Schizzerotto, Antonio

    2017-11-29

    Our contribution assesses the role of information barriers for patterns of participation in Higher Education (HE) and the related social inequalities. For this purpose, we developed a large-scale clustered randomised experiment involving over 9,000 high school seniors from 62 Italian schools. We designed a counseling intervention to correct student misperceptions of the profitability of HE, that is, the costs, economic returns and chances of success of investments in different tertiary programs. We employed a longitudinal survey to test whether treated students' educational trajectories evolved differently relative to a control group. We find that, overall, treated students enrolled less often in less remunerative fields of study in favour of postsecondary vocational programmes. Most importantly, this effect varied substantially by parental social class and level of education. The shift towards vocational programmes was mainly due to the offspring of low-educated parents; in contrast, children of tertiary graduates increased their participation in more rewarding university fields. Similarly, the redistribution from weak fields to vocational programmes mainly involved the children of the petty bourgeoisie and the working class, while upper class students invested in more rewarding university fields. We argue that the status-maintenance model proposed by Breen and Goldthorpe can explain these socially differentiated treatment effects. Overall, our results challenge the claim that student misperceptions contribute to horizontal inequalities in access to HE. © London School of Economics and Political Science 2017.

  8. Multitracing Experiment With Solved and Particulate Tracers In An Unsaturated Field Soil

    Science.gov (United States)

    Burkhardt, M.; Kasteel, R.; Vereecken, H.

    Solute movement and colloid migration follow preferential flow paths in structured soils at the field scale. The use of microsphreres is a possible option to mimic colloid transport through the vadose zone into the groundwater. We present results of multi- tracing experiments conducted in an Orthic Luvisol using bromide (Br-), the reactive dye tracer Brilliant Blue (BB) and microspheres. The fluorescent microspheres (1 and 10 µm in diameter) were functionalized with a negative surface charge. Eight field plots (about 2 m2) were irrigated with 10 mm and 40 mm during 6 h. Four field plots were sampled directly after the irrgation, the others were exposed for 90 days to natural wheather conditions. Photographs of horizontal cross-sections and disturbed soil sam- ples were taken every 5 to 10 cm down to a depth of 160 cm. Image analysis was used to derive concentration distributions of BB using a calibration relationship between concentration and color spectra. The microspheres were quantified after desorption of the soil samples by fluorescent microscopy and image analysis. We used moment analysis to characterize transport phenomena. We found that transport through the soil matrix was affected by sorption, but all of the applied compounds were transported through preferential flow paths (earthworm burrows) down to a depth of 160 cm irre- spective of their chemical properties. Furthermore, this study shows that microspheres can be used to mimic colloid facilitated transport under unsaturated conditions in a field soil.

  9. Impact of warm winters on microbial growth

    Science.gov (United States)

    Birgander, Johanna; Rousk, Johannes; Axel Olsson, Pål

    2014-05-01

    Growth of soil bacteria has an asymmetrical response to higher temperature with a gradual increase with increasing temperatures until an optimum after which a steep decline occurs. In laboratory studies it has been shown that by exposing a soil bacterial community to a temperature above the community's optimum temperature for two months, the bacterial community grows warm-adapted, and the optimum temperature of bacterial growth shifts towards higher temperatures. This result suggests a change in the intrinsic temperature dependence of bacterial growth, as temperature influenced the bacterial growth even though all other factors were kept constant. An intrinsic temperature dependence could be explained by either a change in the bacterial community composition, exchanging less tolerant bacteria towards more tolerant ones, or it could be due to adaptation within the bacteria present. No matter what the shift in temperature tolerance is due to, the shift could have ecosystem scale implications, as winters in northern Europe are getting warmer. To address the question of how microbes and plants are affected by warmer winters, a winter-warming experiment was established in a South Swedish grassland. Results suggest a positive response in microbial growth rate in plots where winter soil temperatures were around 6 °C above ambient. Both bacterial and fungal growth (leucine incorporation, and acetate into ergosterol incorporation, respectively) appeared stimulated, and there are two candidate explanations for these results. Either (i) warming directly influence microbial communities by modulating their temperature adaptation, or (ii) warming indirectly affected the microbial communities via temperature induced changes in bacterial growth conditions. The first explanation is in accordance with what has been shown in laboratory conditions (explained above), where the differences in the intrinsic temperature relationships were examined. To test this explanation the

  10. NDT with the structural weld overlay program. Recent field experience and lessons learned

    International Nuclear Information System (INIS)

    Rishel, R.; Lenz, H.; Turley, G.; Newton, B.

    2007-01-01

    Structural weld overlay (SWOL) has become a predominant mitigation technique within the Alloy 600 program. For the pressurizer nozzles, MRP-139 requires volumetric examination by year end 2007. Many nozzles are un-inspectable due to geometry and material limitations that preclude interrogation of the required examination volume. SWOL therefore is the mitigation technique which overcomes these limitations. SWOL of the pressurizer nozzles has been a challenge for all the vendors. Alloy 52 has proven to be difficult to weld under field conditions. The NDT technique chosen to demonstrate the integrity of the overlay needs to be adapted to the specific repair process and nozzle geometry. The purpose of this paper will be to present Westinghouse's integrated approach for SWOL with the focus on the NDT aspects. Topics will include main repair process steps, NDT qualification, recent field experience and lessons learned. (author)

  11. Interaction between Japanese flowering cherry trees and some wild animals observed during physiological experiment in fields

    Science.gov (United States)

    Nakamura, Teruko

    2003-01-01

    We have studied the weeping habit of Japanese flowering cherry tree in the field of Tama Forest Science Garden, Forestry and Forest Products Research Institute at the foot of Mt. Takao. Since cherry trees at various age were the materials for our plant physiology experiments, our studies were conducted in the fields where we experienced certain difficulties. Even under such difficult environment that was rather unexpected and uncontrollable, we could obtain fruitful results on the growth of cherry tree, and found them scientifically significant, especially in terms of biological effects of gravity on earth. Moreover, a lot of interesting interactions of cherry trees with various kinds of animals were observed in parallel to the plant physiology.

  12. Tokamak Fusion Core Experiment: design studies based on superconducting and hybrid toroidal field coils. Design overview

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, C.A. (ed.)

    1984-10-01

    This document is a design overview that describes the scoping studies and preconceptual design effort performed in FY 1983 on the Tokamak Fusion Core Experiment (TFCX) class of device. These studies focussed on devices with all-superconducting toroidal field (TF) coils and on devices with superconducting TF coils supplemented with copper TF coil inserts located in the bore of the TF coils in the shield region. Each class of device is designed to satisfy the mission of ignition and long pulse equilibrium burn. Typical design parameters are: major radius = 3.75 m, minor radius = 1.0 m, field on axis = 4.5 T, plasma current = 7.0 MA. These designs relay on lower hybrid (LHRH) current rampup and heating to ignition using ion cyclotron range of frequency (ICRF). A pumped limiter has been assumed for impurity control. The present document is a design overview; a more detailed design description is contained in a companion document.

  13. Short-range dynamics and prediction of mesoscale flow patterns in the MISTRAL field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Weber, R.O.; Kaufmann, P.; Talkner, P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    In a limited area of about 50 km by 50 km with complex topography, wind measurements on a dense network were performed during the MISTRAL field experiment in 1991-1992. From these data the characteristic wind fields were identified by an automated classification method. The dynamics of the resulting twelve typical regional flow patterns is studied. It is discussed how transitions between the flow patterns take place and how well the transition probabilities can be described in the framework of a Markov model. Guided by this discussion, a variety of prediction models were tested which allow a short-term forecast of the flow pattern type. It is found that a prediction model which uses forecast information from the synoptic scale has the best forecast skill. (author) 2 figs., 7 refs.

  14. Preparing culturally and linguistically diverse preservice Early Childhood teachers for field experience

    Directory of Open Access Journals (Sweden)

    Melinda Miller

    2016-07-01

    Full Text Available This article reports on an action research project focussed on preparing culturally and linguistically diverse (CALD preservice early childhood teachers for field experience. A series of targeted workshops delivered over one semester was designed to support the students to develop intercultural competence in relation to knowledge, attitude, skills and behaviours that contribute to success on field placement. Findings indicate that short-term initiatives targeted specifically to students’ identified needs and strengths can help to build intercultural competence for both students and teacher educators. For the participants, access to communication strategies, opportunities for rehearsal of teaching practice, and peer and academic support contributed to shifts in attitude, and the development of skills and new knowledge. New learnings for the teacher educators included challenging assumptions about CALD students’ sense of community and belonging in the university context.

  15. Field experiments on solar geoengineering: report of a workshop exploring a representative research portfolio.

    Science.gov (United States)

    Keith, David W; Duren, Riley; MacMartin, Douglas G

    2014-12-28

    We summarize a portfolio of possible field experiments on solar radiation management (SRM) and related technologies. The portfolio is intended to support analysis of potential field research related to SRM including discussions about the overall merit and risk of such research as well as mechanisms for governing such research and assessments of observational needs. The proposals were generated with contributions from leading researchers at a workshop held in March 2014 at which the proposals were critically reviewed. The proposed research dealt with three major classes of SRM proposals: marine cloud brightening, stratospheric aerosols and cirrus cloud manipulation. The proposals are summarized here along with an analysis exploring variables such as space and time scale, risk and radiative forcing. Possible gaps, biases and cross-cutting considerations are discussed. Finally, suggestions for plausible next steps in the development of a systematic research programme are presented.

  16. Plasma performance and scaling laws in the RFX-mod reversed-field pinch experiment

    International Nuclear Information System (INIS)

    Innocente, P.; Alfier, A.; Canton, A.; Pasqualotto, R.

    2009-01-01

    The large range of plasma currents (I p = 0.2-1.6 MA) and feedback-controlled magnetic boundary conditions of the RFX-mod experiment make it well suited to performing scaling studies. The assessment of such scaling, in particular those on temperature and energy confinement, is crucial both for improving the operating reversed-field pinch (RFP) devices and for validating the RFP configuration as a candidate for the future fusion reactors. For such a purpose scaling laws for magnetic fluctuations, temperature and energy confinement have been evaluated in stationary operation. RFX-mod scaling laws have been compared with those obtained from other RFP devices and numerical simulations. The role of the magnetic boundary has been analysed, comparing discharges performed with different active control schemes of the edge radial magnetic field.

  17. Salmon cycles: Influences of a science field study immersion experience with Native American young women

    Science.gov (United States)

    Ault, Phyllis Campbell

    Native Americans, and particularly Native women, are not proportionally represented in higher education, or in science, mathematics, technology, and engineering fields. This study examined an out-of-school science education program which combined traditional Native American cultural and ecological knowledge with Western science in conducting authentic field studies. A qualitative, embedded case study approach was used to explore how young Native American women were influenced by an out-of-school program integrating a culturally responsive approach and experiential research projects. Within this context of combined cultures, three significant domains emerged: field study in science, sense of place, and networks of supportive relationships. These domains interacted with the aspirations of the eight Native women in the study. Using interview transcripts, reflective writings, and participant data, the study explored the blending of Indigenous and Western science in "communities of practice" (e.g., fisheries biology, restoration ecology, and forestry). The eight Native women in this study participated as young adolescents and later returned as counselors. Interviews focused on their postsecondary aspirations and choices. Findings validated previous research on the value of infusing Traditional Ecological Knowledge and Western science for Native students. The study found the combination of culturally responsive pedagogy and authentic experiences in "communities-of-practice" held a beneficial influence on postsecondary pathways. The importance of respect and friendships fostered through the program was associated with resilience and perseverance in educational aspirations. Immersion in field study with Native peers as well as Native and non-Native researchers was a catalyst for all the women, in a number of different ways, such as: deeper involvement with the Native community, strengthening cultural and academic identity, inspiration to learn more about their cultural

  18. Monitoring and enforcement of environmental regulations. Lessons from a natural field experiment in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Telle, Kjetil

    2012-07-01

    Relying on a small natural field experiment with random assignment of treatments, I estimate effects of three core elements of most monitoring and enforcement practices: self-reporting, audit frequency and specific deterrence. I find evidence of evasive reporting of violations in self-audits, as more violations are detected in on-site audits than in self-audits. Announcing the increased audit frequency has no effect on compliance, but an audit raises the firm's subsequent compliance substantially.(Author)

  19. Discrimination in the housing market — a field experiment on the internet

    OpenAIRE

    Ahmed, Ali; Hammarstedt, Mats

    2007-01-01

    This paper studies ethnic and gender discrimination in the housing market in Sweden with the help of a field experiment on the internet. By letting three testers, one with a typical male Swedish name, one with a typical female Swedish name, and one with a typical male Arabic/Muslim name apply for vacant rental apartments advertised by landlords on the internet, we explore the incidence of discrimination in the choice by landlords to invite applicants to further contacts and/or to a showing of...

  20. Optimizing ssNMR experiments for dilute proteins in heterogeneous mixtures at high magnetic fields.

    Science.gov (United States)

    McNeill, Seth A; Gor'kov, Peter L; Struppe, Jochem; Brey, William W; Long, Joanna R

    2007-12-01

    Solid-state NMR spectroscopy at high magnetic fields is proving to be an effective technique in structural biology, particularly for proteins which are not amenable to traditional X-ray and solution NMR approaches. Several parameters can be selected to provide optimal sensitivity, improve sample stability, and ensure biological relevance for ssNMR measurements on protein samples. These include selection of sample conditions, NMR probe design, and design of pulse experiments. Here, we demonstrate and evaluate several engineering and experimental approaches for pursuing measurements on dilute proteins in heterogeneous mixtures. Copyright © 2007 John Wiley & Sons, Ltd.

  1. Orientationally invariant metrics of apparent compartment eccentricity from double pulsed field gradient diffusion experiments

    DEFF Research Database (Denmark)

    Jespersen, Sune Nørhøj; Lundell, Henrik; Sønderby, Casper Kaae

    2013-01-01

    pairs of diffusion wave vectors (the d-PFG 5-design) facilitating a theoretically exact determination of the fourth order Taylor or cumulant expansion of the orientationally averaged signal. The d-PFG 5-design is evaluated with numerical simulations and ex vivo high field diffusion MRI experiments...... orientation dispersion when applied to macroscopically anisotropic systems. Here we propose a new framework, the d-PFG 5-design, to enable rotationally invariant estimation of double wave vector diffusion metrics (d-PFG). The method is based on the idea that an appropriate orientational average of the signal...

  2. A Field Experiment on Search Costs and the Formation of Scientific Collaborations.

    Science.gov (United States)

    Boudreau, Kevin J; Brady, Tom; Ganguli, Ina; Gaule, Patrick; Guinan, Eva; Hollenberg, Anthony; Lakhani, Karim R

    2017-10-01

    We present the results of a field experiment conducted at Harvard Medical School to understand the extent to which search costs affect matching among scientific collaborators. We generated exogenous variation in search costs for pairs of potential collaborators by randomly assigning individuals to 90-minute structured information-sharing sessions as part of a grant funding opportunity. We estimate that the treatment increases the probability of grant co-application of a given pair of researchers by 75%. The findings suggest that matching between scientists is subject to considerable frictions, even in the case of geographically-proximate scientists working in the same institutional context.

  3. An anaerobic field injection experiment in a landfill leachate plume (Grindsted, Denmark)

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Bjerg, Poul Løgstrup; Ludvigsen, L.

    1999-01-01

    Redox conditions may be environmental factors which affect the fate of the xenobiotic organic compounds. Therefore the redox conditions were characterized in an anaerobic, leachate-contaminated aquifer 15–60 m downgradient from the Grindsted Landfill, Denmark, where an field injection experiment ...... electron acceptor in the region of the aquifer, which was investigated. Because of the complexity of a landfill leachate plume, several redox processes may occur simultaneously, and an array of methods must be applied for redox characterization in such multicomponent systems....

  4. Reynolds and Maxwell stress measurements in the reversed field pinch experiment Extrap-T2R

    Science.gov (United States)

    Vianello, N.; Antoni, V.; Spada, E.; Spolaore, M.; Serianni, G.; Cavazzana, R.; Bergsåker, H.; Cecconello, M.; Drake, J. R.

    2005-08-01

    The complete Reynolds stress (RS) has been measured in the edge region of the Extrap-T2R reversed field pinch experiment. The RS exhibits a strong gradient in the region where a high E × B shear takes place. Experimental results show this gradient to be almost entirely due to the electrostatic contribution. This has been interpreted as experimental evidence of flow generation via turbulence mechanism. The scales involved in flow generation are deduced from the frequency decomposition of RS tensor. They are found related to magnetohydrodynamic activity but are different with respect to the scales responsible for turbulent transport.

  5. Innovating the Experience of Peer Learning and Earth Science Education in the Field

    Science.gov (United States)

    Scoates, J. S.; Hanano, D. W.; Weis, D.; Bilenker, L.; Sherman, S. B.; Gilley, B.

    2017-12-01

    The use of active learning and collaborative strategies is widely gaining momentum at the university level and is ideally suited to field instructional settings. Peer learning, when students learn with and from each other, is based on the principle that students learn in a more profound way by explaining their ideas to others and by participating in activities in which they can learn from their peers. The Multidisciplinary Applied Geochemistry Network (MAGNET), an NSERC Collaborative Research and Training Experience (CREATE) initiative in Canada, recently experimented with this approach during its fourth annual workshop in August 2016. With a group of 25 geochemistry graduate students from universities across Canada, three remarkable field sites in Montana and Wyoming were explored: the Stillwater Complex, the Beartooth Mountains, and Yellowstone National Park. Rather than developing a rigorous teaching curriculum led by faculty, groups of students were tasked with designing and delivering half-day teaching modules that included field activities at each of the locations. Over the course of two months and with feedback from mentors, the graduate students transformed their ideas into formal lesson plans, complete with learning goals, a schedule of teaching activities, equipment lists, and plans for safety and environmental mitigation. This shift, from teacher-centered to learner-centered education, requires students to take greater initiative and responsibility for their own learning and development. We highlight the goals, structure and implementation of the workshop, as well as some of the successes and challenges. We also present the results of participant feedback taken immediately after each lesson and both pre- and post-trip surveys. The outdoor classroom and hands-on activities accelerated learning of field techniques and enhanced understanding of complex geological systems and processes. The trainee-led format facilitated peer knowledge transfer and the

  6. Discrete and continuum simulations of near-field ground motion from Source Physics Experiments (SPE) (Invited)

    Science.gov (United States)

    Ezzedine, S. M.; Vorobiev, O.; Herbold, E. B.; Glenn, L. A.; Antoun, T.

    2013-12-01

    This work is focused on analysis of near-field measurements (up to 100 m from the source) recorded during Source Physics Experiments in a granitic formation. One of the main goals of these experiments is to investigate the possible mechanisms of shear wave generation in the nonlinear source region. SPE experiments revealed significant tangential motion (up to 30 % of the magnitude in the radial direction) at many locations. Furthermore, azimuthal variations in radial velocities were also observed which cannot be generated by a spherical source in isotropic materials. Understanding the nature of this non-radial motion is important for discriminating between the natural seismicity and underground explosions signatures. Possible mechanisms leading to such motion include, but not limited to, heterogeneities in the rock such as joints, faults and geologic layers as well as surface topography and vertical motion at the surface caused by material spall and gravity. We have performed a three dimensional computational studies considering all these effects. Both discrete and continuum methods have been employed to model heterogeneities. In the discrete method, the joints and faults were represented by cohesive contact elements. This enables us to examine various friction laws at the joints which include softening, dilatancy, water saturation and rate-dependent friction. Yet this approach requires the mesh to be aligned with joints, which may present technical difficulties in three dimensions when multiple non-persistent joints are present. In addition, the discrete method is more computationally expensive. The continuum approach assumes that the joints are stiff and the dilatancy and shear softening can be neglected. In this approach, the joints are modeled as weakness planes within the material, which are imbedded into and pass through many finite elements. The advantage of this approach is that it requires neither sophisticated meshing algorithms nor contact detection

  7. Evaluation of tetroon flights and turbulent diffusion under weak wind conditions during the field experiment SIESTA

    International Nuclear Information System (INIS)

    Hu Erbang; Vogt, S.

    1986-08-01

    During several days in November 1985 an international field experiment took place in the Swiss plateau region near the cities of Aarau, Olten. As indicated by the name of the project SIESTA (SF 6 International Experiments in Stagnant Air) its aim is to obtain knowledge of the general nature of turbulence advection and atmospheric dispersion processes in a cold pool with very low wind speed and undefined wind direction. An outline of the general concept of the project is followed by a more detailed description of a special research activity with Radar tracked tetroons. In the second part of the report it is shown how to determine the horizontal dispersion parameter from the trajectories of the tetroon flights. Two different methods are described and the results of the flights performed during SIESTA are presented. (orig.) [de

  8. Using Economic Incentives to Reduce Electricity Consumption: A field Experiment in Matsuyama, Japan

    Directory of Open Access Journals (Sweden)

    Kenichi Mizobuchi

    2012-01-01

    Full Text Available This study examines the effectiveness of economic incentives in promoting electricity-conservation behavior among Japanese households. Fifty-three Japanese households participated in a field experiment and were offered monetary rewards depending on their rate of reduction in electricity consumption. To avoid bias in sample selection, which is typically present in previous studies, we adopted a request-based approach for recruiting participants. Results showed that only 34% of the participants succeeded in reducing their electricity consumption, and the average reduction rate was –4.8%. Econometric analysis confirmed that monetary rewards had a positive influence on the electricity conservation behavior, especially of family members who typically stay at home on weekdays. Responses to the questionnaires administered before and after the experiment suggest that participants may have underestimated the marginal costs of the electricity conservation behavior. The efficacy of economic incentives, established in our study, offers a potential measure for encouraging electricity-conservation behavior among Japanese households.

  9. Silica-coated titania and zirconia colloids for subsurface transport field experiments

    Science.gov (United States)

    Ryan, Joseph N.; Elimelech, Menachem; Baeseman, Jenny L.; Magelky, Robin D.

    2000-01-01

    Silica-coated titania (TiO2) and zirconia (ZrO2) colloids were synthesized in two sizes to provide easily traced mineral colloids for subsurface transport experiments. Electrophoretic mobility measurements showed that coating with silica imparted surface properties similar to pure silica to the titania and zirconia colloids. Measurements of steady electrophoretic mobility and size (by dynamic light scattering) over a 90-day period showed that the silica-coated colloids were stable to aggregation and loss of coating. A natural gradient field experiment conducted in an iron oxide-coated sand and gravel aquifer also showed that the surface properties of the silica-coated colloids were similar. Colloid transport was traced at μg L-1 concentrations by inductively coupled plasma-atomic emission spectroscopy measurement of Ti and Zr in acidified samples.

  10. Advanced Biasing Experiments on the C-2 Field-Reversed Configuration Device

    Science.gov (United States)

    Thompson, Matthew; Korepanov, Sergey; Garate, Eusebio; Yang, Xiaokang; Gota, Hiroshi; Douglass, Jon; Allfrey, Ian; Valentine, Travis; Uchizono, Nolan; TAE Team

    2014-10-01

    The C-2 experiment seeks to study the evolution, heating and sustainment effects of neutral beam injection on field-reversed configuration (FRC) plasmas. Recently, substantial improvements in plasma performance were achieved through the application of edge biasing with coaxial plasma guns located in the divertors. Edge biasing provides rotation control that reduces instabilities and E × B shear that improves confinement. Typically, the plasma gun arcs are run at ~ 10 MW for the entire shot duration (~ 5 ms), which will become unsustainable as the plasma duration increases. We have conducted several advanced biasing experiments with reduced-average-power plasma gun operating modes and alternative biasing cathodes in an effort to develop an effective biasing scenario applicable to steady state FRC plasmas. Early results show that several techniques can potentially provide effective, long-duration edge biasing.

  11. The relative benefits of green versus lean office space: three field experiments.

    Science.gov (United States)

    Nieuwenhuis, Marlon; Knight, Craig; Postmes, Tom; Haslam, S Alexander

    2014-09-01

    Principles of lean office management increasingly call for space to be stripped of extraneous decorations so that it can flexibly accommodate changing numbers of people and different office functions within the same area. Yet this practice is at odds with evidence that office workers' quality of life can be enriched by office landscaping that involves the use of plants that have no formal work-related function. To examine the impact of these competing approaches, 3 field experiments were conducted in large commercial offices in The Netherlands and the U.K. These examined the impact of lean and "green" offices on subjective perceptions of air quality, concentration, and workplace satisfaction as well as objective measures of productivity. Two studies were longitudinal, examining effects of interventions over subsequent weeks and months. In all 3 experiments enhanced outcomes were observed when offices were enriched by plants. Implications for theory and practice are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  12. Forest litter crickets prefer higher substrate moisture for oviposition: Evidence from field and lab experiments.

    Science.gov (United States)

    de Farias-Martins, Fernando; Sperber, Carlos Frankl; Albeny-Simões, Daniel; Breaux, Jennifer Ann; Fianco, Marcos; Szinwelski, Neucir

    2017-01-01

    For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry) to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i) presence or absence of eggs in each sampling unit as binary response variable, and (ii) number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM) with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid) increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying.

  13. Forest litter crickets prefer higher substrate moisture for oviposition: Evidence from field and lab experiments

    Science.gov (United States)

    Sperber, Carlos Frankl; Albeny-Simões, Daniel; Breaux, Jennifer Ann; Fianco, Marcos; Szinwelski, Neucir

    2017-01-01

    For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry) to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i) presence or absence of eggs in each sampling unit as binary response variable, and (ii) number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM) with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid) increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying. PMID:28977023

  14. Forest litter crickets prefer higher substrate moisture for oviposition: Evidence from field and lab experiments.

    Directory of Open Access Journals (Sweden)

    Fernando de Farias-Martins

    Full Text Available For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i presence or absence of eggs in each sampling unit as binary response variable, and (ii number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying.

  15. Field experiments to determine wave propagation principles and mechanical properties of snow

    Science.gov (United States)

    Simioni, Stephan; Gebhard, Felix; Dual, Jürg; Schweizer, Jürg

    2017-04-01

    To understand the release of snow avalanches by explosions one needs to know how acoustic waves travel above and within the snowpack. Hitherto, wave propagation was investigated in the laboratory with small samples or in the field in the shock wave region. We developed a measurement system and layout to derive wave attenuation in snow, wave speeds and elastic moduli on small-scale (1-2 m) field experiments to close the gap between the lab scale (0.1 m) and the scale of artificial release (10-100 m). We used solid explosives and hammer blows to create the load and accelerometers to measure the resulting wave within the snowpack. The strong attenuation we observed indicates that we measured the second longitudinal wave which propagates through the pore space. The wave speeds, however, corresponded to the speeds of the first longitudinal wave within the ice skeleton. The elastic moduli were high on the order of several tens of MPa for lower densities (150 kg m-3) and agreed well with earlier lab studies, in particular for the higher densities 250-400 kg m-3). However, the scatter was rather large as expected for in-situ experiments in the layered snow cover. In addition, we measured accelerations during propagation saw test experiments. The propagation of cracks during this type of snow instability test has mainly been studied by analysing the bending of the slab (due to the saw cut) using particle tracking velocimetry. We used the accelerometers to measure crack propagation speeds. The wave speeds were slightly higher for most experiments than reported previously. Furthermore, in some experiments, we encountered to different wave types with one propagating at a higher speed. This finding may be interpreted as the actual crack propagation and the settling of the weak layer (collapse wave). Our results show that field measurements of propagation properties are feasible and that crack propagation as observed during propagation saw tests may involve different processes

  16. Cs-137 soil to plant transfer factors derived from pot experiments and field studies

    International Nuclear Information System (INIS)

    Horak, O.; Gerzabek, M.H.; Mueck, K.

    1989-11-01

    Soil to plant transfer factors (TF) of 137 Cs for different crop plants were determined in pot experiments, in outdoor experiments with plastic containers of 50 l volume, and in field studies. In all cases the soil contamination with 137 Cs resulted from fallout after the Chernobyl reactor accident. Mean TF derived for outdoor plants on a fresh weight basis, ranged from 0,0017 (leaf vegetables) to 0,059 (rye straw) and showed characteristic differences depending on plant part and species. Generally, for fruits and potato tubers a lower TF was found than for vegetative plant parts. Moreover, the data were compared with those from former experiments, carried out before the Chernobyl accident. There is a good agreement for cereals (with exception of rye) fruit vegetables and fodder crops, while actual TF are substantially lower for potatoes, leaf and root vegetables, but higher for rye. A significant negative correlation was observed between the TF and the soil activity concentrations for 137 Cs. In container experiments the TF were found to be influenced mainly by the clay content of the soil. 11 refs., 2 figs., 2 tabs. (Authors)

  17. Refinement but Not Maintenance of Visual Receptive Fields Is Independent of Visual Experience

    Science.gov (United States)

    Balmer, Timothy S.; Pallas, Sarah L.

    2015-01-01

    Visual deprivation is reported to prevent or delay the development of mature receptive field (RF) properties in primary visual cortex (V1) in several species. In contrast, visual deprivation neither prevents nor delays refinement of RF size in the superior colliculus (SC) of Syrian hamsters, although vision is required for RF maintenance in the SC. Here, we report that, contrary to expectation, visual cortical RF refinement occurs normally in dark-reared animals. As in the SC, a brief period of visual experience is required to maintain V1 RF refinement in adulthood. Whereas in the SC, 3 days of visual experience within a sensitive period (P37–40) was sufficient to protect RFs from deprivation-induced enlargement in adulthood, 7 days (P33–40) were required for RF size maintenance in V1. Thus, spontaneous activity is sufficient for RF refinement at these 2 levels of the visual pathway, and visual input is necessary only to prevent deprivation-induced RF enlargement in adulthood. These studies show that sensory experience during a late juvenile sensitive period protects the visual pathway against sensory deprivation in adulthood, and suggest that more importance may have been placed on the role of early visual experience in visual RF development than is warranted. PMID:24108803

  18. Climate and smoke: an appraisal of nuclear winter.

    Science.gov (United States)

    Turco, R P; Toon, O B; Ackerman, T P; Pollack, J B; Sagan, C

    1990-01-12

    The latest understanding of nuclear winter is reviewed. Considerable progress has been made in quantifying the production and injection of soot by large-scale fires, the regional and global atmospheric dispersion of the soot, and the resulting physical, environmental, and climatic perturbations. New information has been obtained from laboratory studies, field experiments, and numerical modeling on a variety of scales (plume, mesoscale, and global). For the most likely soot injections from a full-scale nuclear exchange, three-dimensional climate simulations yield midsummer land temperature decreases that average 10 degrees to 20 degrees C in northern mid-latitudes, with local cooling as large as 35 degrees C, and subfreezing summer temperatures in some regions. Anomalous atmospheric circulations caused by solar heating of soot is found to stabilize the upper atmosphere against overturning, thus increasing the soot lifetime, and to accelerate interhemispheric transport, leading to persistent effects in the Southern Hemisphere. Serious new environmental problems associated with soot injection have been identified, including disruption of monsoon precipitation and severe depletion of the stratospheric ozone layer in the Northern Hemisphere. The basic physics of nuclear winter has been reaffirmed through several authoritative international technical assessments and numerous individual scientific investigations. Remaining areas of uncertainty and research priorities are discussed in view of the latest findings.

  19. Optimal Cross Hedging Winter Canola

    OpenAIRE

    Kim, Seon-Woong; Brorsen, B. Wade; Yoon, Byung-Sam

    2014-01-01

    Winter canola in the southern Great Plains has shown large price fluctuations and there have been questions about which futures market could be used to reduce price risk. Our results indicate that the optimal futures contract to cross hedge winter canola is soybean oil futures.

  20. A field application experience of integrating hydrogen technology with wind power in a remote island location

    Science.gov (United States)

    Gazey, R.; Salman, S. K.; Aklil-D'Halluin, D. D.

    This paper aims to share the field application experience related to the development of an innovative stand-alone sustainable energy system known as the PURE project. The PURE project has been developed alongside a Knowledge Transfer Partnership (KTP) scheme, which is supported by the UK Department of Trade and Industry and executed by siGEN in collaboration with The Robert Gordon University. The system has been constructed within an industrial estate on the island of Unst in Shetland, 200 miles north of the Scottish mainland. The energy system now supplies five business properties with clean reliable power and utilises wind turbine and hydrogen technology to provide a sustainable energy source. The stored hydrogen gas generated by the system is used as an energy source for periods when electrical demand within the business properties exceeds wind turbine production. The hydrogen is also utilised as a fuel source for transportation and as a transportable energy source for mobile power generation. The paper therefore gives a detailed description of the PURE project and discusses the field experience accumulated during the development and installation of the system. It also shares a number of practical issues that had to be overcome during its integration and operation. The installation of the PURE project has resulted in a number of unexpected conclusions being identified and marks a significant step forward in the accessible deployment of this technology for community use.

  1. Meta-analysis of field experiments shows no change in racial discrimination in hiring over time.

    Science.gov (United States)

    Quillian, Lincoln; Pager, Devah; Hexel, Ole; Midtbøen, Arnfinn H

    2017-10-10

    This study investigates change over time in the level of hiring discrimination in US labor markets. We perform a meta-analysis of every available field experiment of hiring discrimination against African Americans or Latinos ( n = 28). Together, these studies represent 55,842 applications submitted for 26,326 positions. We focus on trends since 1989 ( n = 24 studies), when field experiments became more common and improved methodologically. Since 1989, whites receive on average 36% more callbacks than African Americans, and 24% more callbacks than Latinos. We observe no change in the level of hiring discrimination against African Americans over the past 25 years, although we find modest evidence of a decline in discrimination against Latinos. Accounting for applicant education, applicant gender, study method, occupational groups, and local labor market conditions does little to alter this result. Contrary to claims of declining discrimination in American society, our estimates suggest that levels of discrimination remain largely unchanged, at least at the point of hire.

  2. The CGEM-IT of the BESIII experiment: project update and test results in magnetic field

    Science.gov (United States)

    Mezzadri, G.

    2016-08-01

    The BESIII experiment is a multi-purpose detector operating on the electron- positron collider BEPCII in Beijing. Since 2008, the world's largest sample of J/ψ, ψ’ were collected. Due to increasing luminosity, the inner drift chamber is showing signs of aging. In 2014, an upgrade was proposed by the Italian collaboration based on the Cylindrical Gas Electron Multipliers (CGEM) technology, developed within the KLOE-II experiment, but with several new features and innovations. In this contribution, an overview of the project will be presented. Preliminary results of a beam test will be shown, with particular focus on the detector performance in magnetic field, with different configurations of electric field. A new readout mode, the µTPC readout, will also be described. The project has been recognized as a Significant Research Project within the Executive Programme for Scientific and Technological Cooperation between Italy and P.R.C for the years 2013-2015, and more recently has been selected as one of the project funded by the European Commission within the call H2020- MSCA-RISE-2014.

  3. Vegetation water content mapping in a diverse agricultural landscape: National Airborne Field Experiment 2006

    Science.gov (United States)

    Cosh, Michael H.; Tao, Jing; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2010-05-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE'06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE'06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/m2. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy.

  4. Winter wheat grain yield and its components in the North China Plain: irrigation management, cultivation, and climate

    OpenAIRE

    Lihua Lv; Yanrong Yao; Lihua Zhang; Zhiqiang Dong; Xiuling Jia; Shuangbo Liang; Junjie Ji

    2013-01-01

    Irrigation has been identified as the main driving factor of groundwater drawdown in the North China Plain (NCP). In order to develop appropriate irrigation strategies for satisfactory yields of wheat (Triticum aestivum L.), grain yield (GY), yield components, and water use efficiency (WUE) were studied. A field experiment was conducted with two types of winter wheat, 'Shimai15' and 'Shixin733', and five irrigation treatments, including rainfed and four spring irrigation water applications, i...

  5. Development of a summer field-based hydrogeology research experience for undergraduates

    Science.gov (United States)

    Singha, K.

    2011-12-01

    A critical problem in motivating and training the next generation of environmental scientists is providing them with an integrated scientific experience that fosters a depth of understanding and helps them build a network of colleagues for their future. As the education part of an NSF-funded CAREER proposal, I have developed a three-week summer research experience for undergraduate students that links their classroom education with field campaigns aiming to make partial differential equations come "alive" in a practical, applied setting focused on hydrogeologic processes. This course has been offered to freshman- to junior-level undergraduate students from Penn State and also the three co-operating Historically Black Universities (HBUs)--Jackson State University, Fort Valley State University, and Elizabeth City State University-since 2009. Broad learning objectives include applying their knowledge of mathematics, science, and engineering to flow and transport processes in the field and communicating science effectively in poster and oral format. In conjunction with ongoing research about solute transport, students collected field data in the Shale Hills Critical Zone Observatory in Central Pennsylvania, including slug and pumping tests, ground-penetrating radar, electrical resistivity imaging, wireline logging, and optical televiewers, among other instruments. Students conducted tracer tests, where conservative solutes are introduced into a local stream and monitored. Students also constructed numerical models using COMSOL Multiphysics, a research-grade code that can be used to model any physical system; with COMSOL, students create models without needing to be trained in computer coding. With guidance, students built basic models of fluid flow and transport to visualize how heterogeneity of hydraulic and transport properties or variations in forcing functions impact their results. The development of numerical models promoted confidence in predicting flow and

  6. Coping with the challenges of early disaster response: 24 years of field hospital experience after earthquakes.

    Science.gov (United States)

    Bar-On, Elhanan; Abargel, Avi; Peleg, Kobi; Kreiss, Yitshak

    2013-10-01

    To propose strategies and recommendations for future planning and deployment of field hospitals after earthquakes by comparing the experience of 4 field hospitals deployed by The Israel Defense Forces (IDF) Medical Corps in Armenia, Turkey, India and Haiti. Quantitative data regarding the earthquakes were collected from published sources; data regarding hospital activity were collected from IDF records; and qualitative information was obtained from structured interviews with key figures involved in the missions. The hospitals started operating between 89 and 262 hours after the earthquakes. Their sizes ranged from 25 to 72 beds, and their personnel numbered between 34 and 100. The number of patients treated varied from 1111 to 2400. The proportion of earthquake-related diagnoses ranged from 28% to 67% (P earthquakes, patient caseload and treatment requirements varied widely. The variables affecting the patient profile most significantly were time until deployment, total number of injured, availability of adjacent medical facilities, and possibility of evacuation from the disaster area. When deploying a field hospital in the early phase after an earthquake, a wide variability in patient caseload should be anticipated. Customization is difficult due to the paucity of information. Therefore, early deployment necessitates full logistic self-sufficiency and operational versatility. Also, collaboration with local and international medical teams can greatly enhance treatment capabilities.

  7. A Cryogen-free Cryostat for Scientific Experiment in Pulsed High Magnetic Fields

    Science.gov (United States)

    Wang, Shaoliang; Li, Liang; Zuo, Huakun; Liu, Mengyu; Peng, Tao

    Traditional cryostats for scientific experiments in pulsed high magnetic fields use liquid helium as the cooling source. To reduce the running cost and to increase the operational efficiency, a cryogen-free cryostat based on a GM cryocooler has been developed for a 60 T pulsed field measurement cell at Wuhan National High Magnetic Field Center. A double layer temperature-control insert was designed to obtain a stable temperature in the sample chamber of the cryostat. In order to eliminate the sample temperature fluctuation caused by the eddy current heating during the pulse, the inner layer is made from a fiberglass tubing with an epoxy coating. Different from the traditional cryostat, the sample and the temperature controller are not immerged in the 4He bath. Instead, they are separated by helium gas under sub-atmospheric pressure, which makes the heat transfer smoother. At the sample position, a resistance heater wound with antiparallel wires is mounted on the inner layer to heat the sample. Using the temperature-control insert, the temperature can be controlled with an accuracy of ±0.01 K in the range of 1.4 K-20 K, and ±0.05 K between 20 K and 300 K.

  8. Phase-locking of tearing modes in the reversed field experiment

    Science.gov (United States)

    Fitzpatrick, Richard; Zanca, Paolo

    2002-06-01

    In the reversed field experiment (RFX) [F. Gnesotto et al., Fusion Eng. Des. 25, 335 (1995)], the m=1 and m=0 tearing modes present in the plasma are observed to phase-lock together to form a highly peaked, strongly toroidally localized, pattern in the perturbed magnetic field. This pattern, which is commonly known as the "slinky" pattern, gives rise to severe edge loading problems which limit the maximum achievable toroidal current. A theory is presented which explains virtually all salient features of the RFX slinky pattern. The central premise of this theory is that at high ambient mode amplitude the various tearing modes occurring in the plasma phase-lock together in a configuration which minimizes the magnitudes of the electromagnetic torques exerted at the various mode rational surfaces. The theory successfully predicts the profiles of the edge radial and toroidal magnetic fields generated by the m=0 and m=1 modes, the phase relations between the various modes, the presence of a small toroidal offset between the peaks of the m=0 and m=1 contributions to the overall slinky pattern, and the response of the pattern to externally generated m=0 and m=1 magnetic perturbations.

  9. Phase-locking of tearing modes in the reversed field experiment

    International Nuclear Information System (INIS)

    Fitzpatrick, Richard; Zanca, Paolo

    2002-01-01

    In the reversed field experiment (RFX) [F. Gnesotto et al., Fusion Eng. Des. 25, 335 (1995)], the m=1 and m=0 tearing modes present in the plasma are observed to phase-lock together to form a highly peaked, strongly toroidally localized, pattern in the perturbed magnetic field. This pattern, which is commonly known as the 'slinky' pattern, gives rise to severe edge loading problems which limit the maximum achievable toroidal current. A theory is presented which explains virtually all salient features of the RFX slinky pattern. The central premise of this theory is that at high ambient mode amplitude the various tearing modes occurring in the plasma phase-lock together in a configuration which minimizes the magnitudes of the electromagnetic torques exerted at the various mode rational surfaces. The theory successfully predicts the profiles of the edge radial and toroidal magnetic fields generated by the m=0 and m=1 modes, the phase relations between the various modes, the presence of a small toroidal offset between the peaks of the m=0 and m=1 contributions to the overall slinky pattern, and the response of the pattern to externally generated m=0 and m=1 magnetic perturbations

  10. Tracer tomography: design concepts and field experiments using heat as a tracer.

    Science.gov (United States)

    Doro, Kennedy O; Cirpka, Olaf A; Leven, Carsten

    2015-04-01

    Numerical and laboratory studies have provided evidence that combining hydraulic tomography with tomographic tracer tests could improve the estimation of hydraulic conductivity compared with using hydraulic data alone. Field demonstrations, however, have been lacking so far, which we attribute to experimental difficulties. In this study, we present a conceptual design and experimental applications of tracer tomography at the field scale using heat as a tracer. In our experimental design, we improve active heat tracer testing by minimizing possible effects of heat losses, buoyancy, viscosity, and changing boundary conditions. We also utilize a cost-effective approach of measuring temperature changes in situ at high resolution. We apply the presented method to the 8 m thick heterogeneous, sandy gravel, alluvial aquifer at the Lauswiesen Hydrogeological Research Site in Tübingen, Germany. Results of our tomographic heat-tracer experiments are in line with earlier work on characterizing the aquifer at the test site. We demonstrate from the experimental perspective that tracer tomography is applicable and suitable at the field scale using heat as a tracer. The experimental results also demonstrate the potential of heat-tracer tomography as a cost-effective means for characterizing aquifer heterogeneity. © 2014, National Ground Water Association.

  11. Machine Vision System for Characterizing the Electric Field for the 225 Ra EDM Experiment

    Science.gov (United States)

    Sanchez, Andrew

    2017-09-01

    If an atom or fundamental particle possesses an electric dipole moment (EDM), that would imply time-reversal violation. At our current capability, if an EDM is detected in such a particle, that would suggest the discovery of beyond the standard model (BSM) physics. The unique structure of 225 Ra makes its atomic EDM favorable in the BSM search. An upgraded Ra-EDM apparatus will increase experimental sensitivity and the target electric field of 150 kV/cm will more than double the electric field used in previous experiments. To determine the electric field, the potential difference and electrode separation distance must be known. The optical method I have developed is a high-precision, non-invasive technique to measure electrode separation without making contact with the sensitive electrode surfaces. A digital camera utilizes a bi-telecentric lens to reduce parallax error and produce constant magnification throughout the optical system, regardless of object distance. A monochrome LED backlight enhances sharpness of the electrode profile, reducing uncertainty in edge determination and gap width. A program utilizing an edge detection algorithm allows precise, repeatable measurement of the gap width to within 1% and measurement of the relative angle of the electrodes. This work (SAM, Ra EDM) is supported by Michigan State University. This work (REU Program) is supported by U.S. National Science Foundation under Grant Number #1559866.

  12. Estimation of winter rye (Secale cereale L. susceptibility to infection by powdery mildew (Blumeria graminis F. sp. secalis

    Directory of Open Access Journals (Sweden)

    Henryk Bujak

    2013-10-01

    Full Text Available In cold and wet years, powdery mildew (Blumeria graminis causes losses in the yield of winter rye (Secale cerale L. amounting to 20%. In order to control the incidence of this disease and reduce the use of fungicides, it is recommendable to grow winter rye cultivars that are resistant or tolerant to infection by Blumeria graminis. The first step in the programmes of resistance-oriented cultivation of winter rye is the choice of adequate components for crossing. Such components should be characterized by resistance to powdery mildew infection, a trait which would be passed onto the new genotypes to be obtained. The paper discusses the outcome of research aimed at selecting inbred lines of winter rye distinguishable by the lowest susceptibility to infection by Blumeria graminis. The evaluation covered 233 winter rye genotypes which had been inoculated with a field population of the pathogen mentioned. The level of infection was defined in a five-point scale from 0 to 4 (the authors’ own scale. Next, the results were analyzed statistically. The genotypes under study were divided using Duncan’s test into homogeneous groups. Seven such groups were distinguished. The first homogeneous group, of the lowest level of infection, comprised five inbred lines of rye. These lines can serve as components for crossing experiments in programmes of resistance-oriented breeding.

  13. Field and laboratory experiments on high dissolution rates of limestone in stream flow

    Science.gov (United States)

    Hattanji, Tsuyoshi; Ueda, Mariko; Song, Wonsuh; Ishii, Nobuyuki; Hayakawa, Yuichi S.; Takaya, Yasuhiko; Matsukura, Yukinori

    2014-01-01

    Field and laboratory experiments were performed to examine dissolution rates of limestone in stream flow. Field experiments were conducted in three stream sites (A-C) with different lithological or hydrological settings around a limestone plateau in the Abukuma Mts., Japan. Sites A and B are allogenic streams, which flow from non-limestone sources into dolines, and site C has a karst spring source. Tablets made of limestone from the same plateau with a diameter of 3.5 cm and a thickness of 1 cm were placed in the streams for 3 years (2008-2011) where alkalinity, pH and major cation concentrations were measured periodically. The saturation indices of calcite (SIc) of stream water were - 2.8 ± 0.4 at site A, - 2.5 ± 0.4 at site B and - 0.5 ± 0.4 at site C. Annual weight loss ratios for tablets were extremely high at site A (0.11-0.14 mg cm- 2 d- 1), high at site B (0.05 mg cm- 2 d- 1), and low at site C (0.005 mg cm- 2 d- 1). The contrasting rates of weight loss are mainly explained by chemical conditions of stream water. In addition, laboratory experiments for dissolution of limestone tablets using a flow-through apparatus revealed that flow conditions around the limestone tablet is another important factor for dissolution in the stream environment. These results revealed that limestone dissolves at a rapid rate where water unsaturated to calcite continuously flows, such as in an allogenic stream.

  14. Winter fuels report

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-04

    The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and state and local governments on the following topics: distillate fuel oil net production, imports and stocks for all PADD's and product supplied on a US level; propane net production, imports and stocks for Petroleum Administration for Defense Districts (PADD) I, II, and III; natural gas supply and disposition, underground storage, and consumption for all PADD's; residential and wholesale pricing data for propane and heating oil for those states participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil price comparisons for the United States and selected cities; and US total heating degree-days by city. This report will be published weekly by the EIA starting the first week in October 1990 and will continue until the first week in April 1991. The data will also be available electronically after 5:00 p.m. on Thursday during the heating season through the EIA Electronic Publication System (EPUB). 12 tabs.

  15. Winter fuels report

    Energy Technology Data Exchange (ETDEWEB)

    1995-01-13

    The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`s, as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 day, 30-Day, and 90-Day outlook for temperature and precipitation and US total heating degree-days by city.

  16. A field experiment with variable-suction multi-compartment samplers to measure the spatio-temporal distribution of solute leaching in an agricultural soil.

    Science.gov (United States)

    Bloem, E; Hogervorst, F A N; de Rooij, G H

    2009-04-01

    Solutes spread out in time and space as they move downwards from the soil surface with infiltrating water. Solute monitoring in the field is often limited to observations of resident concentrations, while flux concentrations govern the movement of solutes in soils. A recently developed multi-compartment sampler is capable of measuring fluxes at a high spatial resolution with minimal disturbance of the local pressure head field. The objective of this paper is to use this sampler to quantify the spatial and temporal variation of solute leaching below the root zone in an agricultural field under natural rainfall in winter and spring. We placed two samplers at 31 and 25 cm depth in an agricultural field, leaving the soil above undisturbed. Each sampler contained 100 separate cells of 31x31 mm. Water fluxes were measured every 5 min for each cell. We monitored leaching of a chloride pulse under natural rainfall by frequently extracting the collected leachate while leaving the samplers buried in situ. This experiment was followed by a dye tracer experiment. This setting yielded information that widely surpassed the information that can be provided by separate anionic and dye tracer trials, and solute transport monitoring by coring or suction cups. The detailed information provided by the samplers showed that percolation at the sampling depth started much faster (approximately 3 h after the start of rainfall) in initially wet soil (pressure head above -65 cm) than in drier soil (more than 14 h at pressure heads below -80 cm). At any time, 25% of the drainage passed through 5-6% of the sampled area, reflecting the effect of heterogeneity on the flow paths. The amount of solute carried by individual cells varied over four orders of magnitude. The lateral concentration differences were limited though. This suggests a convective-dispersive regime despite the short vertical travel distance. On the other hand, the dilution index indicates a slight tendency towards stochastic

  17. Watching eyes on potential litter can reduce littering: evidence from two field experiments

    Directory of Open Access Journals (Sweden)

    Melissa Bateson

    2015-12-01

    Full Text Available Littering constitutes a major societal problem, and any simple intervention that reduces its prevalence would be widely beneficial. In previous research, we have found that displaying images of watching eyes in the environment makes people less likely to litter. Here, we investigate whether the watching eyes images can be transferred onto the potential items of litter themselves. In two field experiments on a university campus, we created an opportunity to litter by attaching leaflets that either did or did not feature an image of watching eyes to parked bicycles. In both experiments, the watching eyes leaflets were substantially less likely to be littered than control leaflets (odds ratios 0.22–0.32. We also found that people were less likely to litter when there other people in the immediate vicinity than when there were not (odds ratios 0.04–0.25 and, in one experiment but not the other, that eye leaflets only reduced littering when there no other people in the immediate vicinity. We suggest that designing cues of observation into packaging could be a simple but fruitful strategy for reducing littering.

  18. Watching eyes on potential litter can reduce littering: evidence from two field experiments.

    Science.gov (United States)

    Bateson, Melissa; Robinson, Rebecca; Abayomi-Cole, Tim; Greenlees, Josh; O'Connor, Abby; Nettle, Daniel

    2015-01-01

    Littering constitutes a major societal problem, and any simple intervention that reduces its prevalence would be widely beneficial. In previous research, we have found that displaying images of watching eyes in the environment makes people less likely to litter. Here, we investigate whether the watching eyes images can be transferred onto the potential items of litter themselves. In two field experiments on a university campus, we created an opportunity to litter by attaching leaflets that either did or did not feature an image of watching eyes to parked bicycles. In both experiments, the watching eyes leaflets were substantially less likely to be littered than control leaflets (odds ratios 0.22-0.32). We also found that people were less likely to litter when there other people in the immediate vicinity than when there were not (odds ratios 0.04-0.25) and, in one experiment but not the other, that eye leaflets only reduced littering when there no other people in the immediate vicinity. We suggest that designing cues of observation into packaging could be a simple but fruitful strategy for reducing littering.

  19. MHD control experiments in the Extrap T2R Reversed Field Pinch

    Science.gov (United States)

    Marrelli, L.; Bolzonella, T.; Brunsell, P.; Cecconello, M.; Drake, J.; Franz, P.; Gregoratto, D.; Manduchi, G.; Martin, P.; Ortolani, S.; Paccagnella, R.; Piovesan, P.; Spizzo, G.; Yadikin, D.; Zanca, P.

    2004-11-01

    We report here on MHD active control experiments performed in the Extrap T2R device, which has been recently equipped with a set of 32 feedback controlled saddle coils couples. Experiments aiming at selectively exciting a resonant resistive instability in order to actively induce Quasi Single Helicity states will be presented. Open loop experiments have in fact shown that a spectrum with one dominant mode can be excited in a high aspect ratio device like T2R. In addition, evidences of controlled braking of tearing modes, which spontaneously rotate in T2R, have been gathered, allowing the determination of a threshold for mode wall locking. Different feedback control schemes have been implemented. In particular, mode suppression schemes proved successful in delaying resistive wall modes growth and in increasing the discharge duration: this suggests a hybrid mode control scenario, in which RWM are suppressed and QSH is induced. Radiation imaging and internal magnetic field reconstructions performed with the ORBIT code will be presented.

  20. NEAR FIELD MODELING OF SPE1 EXPERIMENT AND PREDICTION OF THE SECOND SOURCE PHYSICS EXPERIMENTS (SPE2)

    Energy Technology Data Exchange (ETDEWEB)

    Antoun, T; Xu, H; Vorobiev, O; Lomov, I

    2011-10-20

    Motion along joints and fractures in the rock has been proposed as one of the sources of near-source shear wave generation, and demonstrating the validity of this hypothesis is a focal scientific objective of the source physics experimental campaign in the Climax Stock granitic outcrop. A modeling effort has been undertaken by LLNL to complement the experimental campaign, and over the long term provide a validated computation capability for the nuclear explosion monitoring community. The approach involves performing the near-field nonlinear modeling with hydrodynamic codes (e.g., GEODYN, GEODYN-L), and the far-field seismic propagation with an elastic wave propagation code (e.g., WPP). the codes will be coupled together to provide a comprehensive source-to-sensor modeling capability. The technical approach involves pre-test predictions of each of the SPE experiments using their state of the art modeling capabilities, followed by code improvements to alleviate deficiencies identified in the pre-test predictions. This spiral development cycle wherein simulations are used to guide experimental design and the data from the experiment used to improve the models is the most effective approach to enable a transition from the descriptive phenomenological models in current use to the predictive, hybrid physics models needed for a science-based modeling capability for nuclear explosion monitoring. The objective of this report is to describe initial results of non-linear motion predictions of the first two SPE shots in the Climax Stock: a 220-lb shot at a depth of 180 ft (SPE No.1), and a 2570-lb shot at a depth of 150 ft (SPE No.2). The simulations were performed using the LLNL ensemble granite model, a model developed to match velocity and displacement attenuation from HARDHAT, PILE DRIVER, and SHOAL, as well as Russian and French nuclear test data in granitic rocks. This model represents the state of the art modeling capabilities as they existed when the SPE campaign was