Science.gov

Sample records for chisel plow shovel

  1. Mikkelson sweep/spike chisel plow shovel

    SciTech Connect

    Not Available

    1992-01-01

    Profitability comparisons are reported between the Mikkelson Sweep/Spike Chisel Plow Shovel standard sweeps. This evaluation covers the first year of testing of the new Sweep/Spike design. The data are not averaged over treatments due to significant interaction between treatments and environmental factors. The cost of fuel, fall and spring, to perform the various treatments ranged from $1.27 to $3.36 per acre. Use of the sweep/spike shovel always reduced total fuel cost. Savings varied from $0.11 to $0.71 per acre depending on prior treatment. This means there will be money saved, to off-set expenses, when converting present chisel plows or for special options on new chisel plows, needed for use of the sweep/spike shovel. A summary of 1991--1992 energy measurements. They indicate that more power will be required to pull a chisel plow equipped with the sweep/spike shovel. A larger tractor, narrower chisel plow and/or slower speed will be required to avoid the wheel slippage problems encountered on soft or wet field surfaces.

  2. Mikkelson sweep/spike chisel plow shovel. Economic summary of the 1992 crop season

    SciTech Connect

    Not Available

    1992-12-31

    Profitability comparisons are reported between the Mikkelson Sweep/Spike Chisel Plow Shovel standard sweeps. This evaluation covers the first year of testing of the new Sweep/Spike design. The data are not averaged over treatments due to significant interaction between treatments and environmental factors. The cost of fuel, fall and spring, to perform the various treatments ranged from $1.27 to $3.36 per acre. Use of the sweep/spike shovel always reduced total fuel cost. Savings varied from $0.11 to $0.71 per acre depending on prior treatment. This means there will be money saved, to off-set expenses, when converting present chisel plows or for special options on new chisel plows, needed for use of the sweep/spike shovel. A summary of 1991--1992 energy measurements. They indicate that more power will be required to pull a chisel plow equipped with the sweep/spike shovel. A larger tractor, narrower chisel plow and/or slower speed will be required to avoid the wheel slippage problems encountered on soft or wet field surfaces.

  3. Depth dependence of chisel plow tillage erosion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tillage disturbs the soil vertically, and throws soil in the tillage direction. Tillage movement and disruption of soil is not uniform vertically or horizontally. Tracers have been used to document either the vertical or the horizontal disturbance by tillage, but few studies have examined both the v...

  4. Pegasus plow

    SciTech Connect

    Thacker, G.W.

    1997-04-01

    The Pagasus plow is a new implement for one-pass cotton plowdown. The Pagasus is unique in that it is capable of burying the whole cotton stalk without shredding. A very simple and reliable machine, the Pagasus gives the cotton farmer the option of using controlled traffic tillage without sacrificing good residue burial of easy machine maintenance.

  5. Smarter shovels dig and load more efficiency

    SciTech Connect

    Fiscor, S.

    2009-04-15

    Digital drive upgrades allow older shovels to power through the bank smoothly while improving safety and reliability. The Mine Technology Group of Flanders Electric has pioneered an effort to offer open architecture for shovel electrics by installing Power Performance Digital Drive controls to motors to ensure peak power is provided during the digging process. The new system also has a Smart Fault Recognition system to power down in a controlled fashion. The upgrades have been fitted to Asarco's shovel for use in coal mining operations. 1 fig., 1 photos. 4 figs.

  6. Productivity considerations for shovels and excavators

    SciTech Connect

    Fiscor, S.

    2007-09-15

    During Haulage and Loading 2007, the Engineering and Mining Journal organized an OEM round table discussion with the theme 'Reducing cycle times'. Seven panelists identified areas where they could improve cycle times for open-pit mining. Although the discussions focused mainly on haud trucks, two panelists discussed shovel productivity as it relates to cycle times. Topics ranged from truck-shovel pass matching to payload management. A clear message came through that all the minutes saved per cycle meant nothing if the mine did not have a properly trained operator. The article reports on the discussions. 4 figs.

  7. Smarter shovels dig and load more efficiently

    SciTech Connect

    Fiscor, S.

    2009-03-15

    Digital drive upgrades allow older shovels to power through the bank smoothly while improving safety and reliability. Flanders Electric is currently working on the third of five electric shovel upgrades which consists of Flandex Electric manufactured motors, Allen-Bradley PLCs and the Power Performance Digital Drive upgrade. With an open system, or open architecture, mine operators can service and maintain machines where a close system would limit the electricians to work with the OEMs exclusively. Typically, upgrades replace the old analog or an older digital drive with a new Power Performance Digital Drive upgrade. 1 fig., 2 photos.

  8. 30 CFR 77.409 - Shovels, draglines, and tractors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shovels, draglines, and tractors. 77.409... COAL MINES Safeguards for Mechanical Equipment § 77.409 Shovels, draglines, and tractors. (a) Shovels, draglines, and tractors shall not be operated in the presence of any person exposed to a hazard from...

  9. Optimised dipper fine tunes shovel performance

    SciTech Connect

    Fiscor, S.

    2005-06-01

    Joint efforts between mine operators, OEMs, and researchers yields unexpected benefits from dippers for shovels for coal, oil, or hardrock mining that can now be tailored to meet site-specific conditions. The article outlines a process being developed by CRCMining and P & H MIning Equipment to optimise the dipper that involves rapid prototyping and scale modelling of the dipper and the mine conditions. Scale models have been successfully field tested. 2 photos.

  10. OEM unveil new ideas for shovels and excavators

    SciTech Connect

    Fiscor, S.

    2006-08-15

    From upgrades to new loading arrangements, vendors are looking at new ways to optimize the production process. The paper describes P & M equipment's new C series electric shovels equipped with the centurion system, Hitachi's super-sized excavator to Canadian oil sands, and Bucyrus and Siemens' engineer shovels. 3 figs., 1 photo.

  11. Electric shovels meet the demands for mining operations

    SciTech Connect

    Fiscor, S.

    2008-03-15

    Rugged, intelligent shovels offer better productivity and help mine operators avoid costly downtime in a very tight market. In 2007 P & H Mining Equipment began to produce a new breed of electric mining shovels designed to help reduce operating cost in coal and other mining operations. These were designated the P & H C-Series. All have an advanced communication, command and control system called the Centurion system. Coal mining applications for this series include 4100XPCs in Australia, China and Wyoming, USA. The Centurion system provides information on shovel performance and systems health which is communicated via graphic user interface terminals to the operators cab. Bucyrus International is developing a hydraulic crowd mechanism for its electric shovels and is now field testing one for its 495 series shovel. The company has also added greater capability in the primary software in the drive system for troubleshooting and fault identification to quickly diagnose problems onboard or remotely. 4 photos.

  12. A Wii-related clay-shoveler's fracture.

    PubMed

    Brown, Christopher N; McKenna, Patrick

    2009-01-01

    A 38-year-old man presented to the accident and emergency department complaining of severe neck pain. This had started immediately after swinging his Wii game console control during a rather vigorous game. An X-ray demonstrated a clay-shoveler's fracture of C7. This had radiological features to suggest an acute injury. This is the first report of a clay-shoveler's fracture strongly suggestive of being related to the use of a Wii console. PMID:19882086

  13. An atypical clay shoveler's fracture: a case report

    PubMed Central

    Feldman, Victor B; Astri, Frank

    2001-01-01

    A case of an atypical clay shoveler's fracture with involvement of the spinolaminar line is described. Causative mechanisms of injury, radiographic appearances, differential diagnosis, treatment and prognosis are reviewed. Classic clay shoveler's fractures are considered stable fractures. However, when the spinolaminar line is disrupted, spinal cord involvement must be ruled out. ImagesFigure 1Figure 2Figure 3Figure 4aFigure 4bFigure 5Figure 6

  14. Soil translocation estimates calibrated for moldboard plow depth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past century, one of the biggest culprits of tillage-induced soil erosion and translocation has been the moldboard plow. The distance soil will move by moldboard plow tillage has been shown to be correlated with slope gradient. Lindstrom et al. (1992) developed regression equations describi...

  15. Shovel Operator. Open Pit Mining Job Training Series.

    ERIC Educational Resources Information Center

    Hartley, Larry

    This training outline for shovel operators, one in a series of eight outlines, is designed primarily for company training foremen or supervisors and for trainers to use as an industry-wide guideline for heavy equipment operator training in open pit mining in British Columbia. Intended as a guide for preparation of lesson plans both for classroom…

  16. Confessions of a Shoveler: STS Subcultures and Engineering Ethics

    ERIC Educational Resources Information Center

    Herkert, Joseph R.

    2006-01-01

    Mainstream science, technology, and society scholars have shown little interest in engineering ethics, one going so far as to label engineering ethics activists as "shit shovelers." Detachment from engineering ethics on the part of most STS scholars is related to a broader and long-standing split between the scholar-oriented and activist-oriented…

  17. Clay-Shoveler Fracture in a Paddler: A Case Report.

    PubMed

    Olivier, Etienne Cornelis; Muller, Elouise; Janse van Rensburg, Dina Christina

    2016-05-01

    Clay-shoveler fracture is a fracture of the spinous process of lower cervical and upper thoracic vertebrae. It has only rarely been reported as being caused by an overuse sports injury. This case report describes the first reported clay-shoveler fracture in a paddler. A 51-year-old male paddler, preparing for a paddling adventure over 630 km, felt a click and a sharp pain paravertebrally on the level of the upper thoracic vertebrae while paddling. Sonar investigation did not reveal any muscular injury but computed tomography revealed a fracture of the spinous process of T1. In this case, it is a stress injury due to excessive paddling over a short period of time. This fracture causes debilitating pain in the acute phase and is mainly treated conservatively. PMID:26247546

  18. (Test and gather data on sweep spike combination tillage tool)

    SciTech Connect

    Lukach, J.

    1992-06-19

    This summary presents the data accumulated to date with only brief comment. It is prepared with the intent that the viewers will offer advice on terminology, data presentation, methods and other. The year end analysis will detail changes in the data due to the tillage treatments. The data is incomplete due to equipment problems and time limitations due to the wet fall and early freeze up. The trial was not completed due to our inability to get the Mikkelsen Chisel Plow Shovel (MCP), a 16 inch sweep with an anhydrous knife, to penetrate untilled land. The MCP shovel penetrated to deep on plowed ground and pulled so hard that the front wheels of our JD4440 tractor were jerked off the ground. The Standard Chisel Plow Shovels (SCP), a 16 inch sweep, worked well and the data is included.

  19. [Test and gather data on sweep spike combination tillage tool]. Quarterly technical report, August 1991--March 1992

    SciTech Connect

    Lukach, J.

    1992-06-19

    This summary presents the data accumulated to date with only brief comment. It is prepared with the intent that the viewers will offer advice on terminology, data presentation, methods and other. The year end analysis will detail changes in the data due to the tillage treatments. The data is incomplete due to equipment problems and time limitations due to the wet fall and early freeze up. The trial was not completed due to our inability to get the Mikkelsen Chisel Plow Shovel (MCP), a 16 inch sweep with an anhydrous knife, to penetrate untilled land. The MCP shovel penetrated to deep on plowed ground and pulled so hard that the front wheels of our JD4440 tractor were jerked off the ground. The Standard Chisel Plow Shovels (SCP), a 16 inch sweep, worked well and the data is included.

  20. Clay-shoveler's fracture during indoor rock climbing.

    PubMed

    Kaloostian, Paul E; Kim, Jennifer E; Calabresi, Peter A; Bydon, Ali; Witham, Timothy

    2013-03-01

    Indoor rock climbing is becoming more popular for people of all ages. Despite the tremendous interest in this competitive sport, participants are made aware of the dangers associated with participating. The authors present the first reported case of a clay-shoveler's fracture at the T1 spinous process during indoor rock climbing. They describe the management and natural history of this fracture and discuss management strategies for this increasingly popular recreational sport.A 14-year-old competitive indoor rock climber presented with acute-onset midline thoracic pain at T1 while indoor rock climbing. He reported no recent falls or trauma but stated that the pain came on abruptly while rock climbing. On examination, he was neurologically intact except for significant tenderness to palpation at the T1 spinous process. Magnetic resonance imaging demonstrated a minimally displaced T1 spinous process fracture with evidence of significant surrounding muscular edema, suggesting an acute fracture. He was treated conservatively with anti-inflammatory drugs, complete climbing restriction, and rest. He continued to have focal upper back pain at the level of the fracture over the next 4 months. He was unable to climb for 4 months until his pain resolved after conservative treatment of climbing restriction, pain control, and rest.This is the first documented case of a clay-shoveler's fracture sustained in a pediatric patient directly attributable to indoor rock climbing. PMID:23464962

  1. The terminal effects of chisel-shape projectile penetrating into metallic target plates

    NASA Astrophysics Data System (ADS)

    Tao, Xu; Yao, Xiaohu; Ma, Wei

    2015-09-01

    This work performs the analysis and simulation investigations of penetration behaviors of chisel-shape projectile. In analysis, the projectile is assumed to be a rigid body and the target plate is elastic-plastic material. By introducing the velocity potential function, the velocity field in target is first obtained. Then, the momentum equation is solved for determining the pressure and stress fields in the elastic and plastic regions in target. The variation of the resultant force subjected by the projectiles with the penetration depth is studied. The approximate expressions of penetration depth and the residual velocity with the initial impacting velocity are obtained for the exploration of the penetration mechanisms of the chisel-shape projectile. In numerical simulation, the main attention focuses on the dissipation mechanisms of the kinetic energy of the chisel-shape projectile in penetration process.

  2. Enhancing carbon and nitrogen sequestration in reclaimed soils through organic amendments and chiseling

    SciTech Connect

    Shrestha, R.K.; Lal, R.; Jacinthe, P.A.

    2009-05-15

    The choice of reclamation techniques could affect restoration success, ecosystem productivity, and the capacity of reclaimed mine soil (RMS) to sequester soil organic carbon (SOC). A field experiment was conducted at three reclaimed coal mine sites across eastern Ohio to assess the impact of several reclamation techniques on biomass production, soil properties, and temporal changes in SOC and N pools. Amendments and reclamation practices tested were: normal reclamation practice (NRP, control), cow (Bos taurus) manure (10 Mg ha{sup -1}), mulching with oat straw (15 Mg hat), and chiseling (30-cm depth). At each site, all treatments were applied in triplicate to experimental plots in accord with a randomized complete block design. After 5 yr of restoration, results showed no effect of mulching on any of the soil properties investigated but significant effects of manuring and chiseling. During that period, SOC sequestration rates ranged between 0.6 and 2.8 Mg C ha{sup -1} yr{sup -1}, with the highest rates recorded in the manure-treated plots. Aboveground biomass production, biomass N content, and soil N and SOC pools were also significantly higher in the manure and chiseling treatments, probably due to greater exploration of the soil volume by plant roots and more efficient uptake of water and available nutrients. Ecosystem C (SOC + biomass C) in these two treatments also exceeded that in the NRP by 25 to 27 Mg C ha{sup -}. Thus, manure application and chiseling are effective reclamation practices for restoring RMS.

  3. Comparison of Drilling Performance of Chisel and Button Bits on the Electro Hydraulic Driller

    NASA Astrophysics Data System (ADS)

    Su, Okan; Yarali, Olgay; Akcin, Nuri Ali

    2013-11-01

    Electro hydraulic drillers have been widely used in mining for drilling and roof-bolting. In the drilling process, the performance of the machine is predicted by selecting an appropriate bit type prior to drilling operations. In this paper, a series of field drilling studies were conducted in order to examine and compare the performance of chisel and button bits including wear on the bits. The effects of taper angle on chisel bits, which are at angles of 105°, 110° and 120°, were investigated in terms of rate of penetration, instantaneous drilling rate and specific energy. The results of drilling and abrasivity tests performed in the laboratory supported the outcome of the field studies. Based on laboratory studies and field observations, it was proven that the conglomerate encountered, though it is very abrasive, is easy to drill. The cutter life in the encountered series is also longer in sandstone formation compared to the conglomerate. Additionally, button bits resulted in lower specific energy and higher penetration rates relative to chisel bits, regardless of their taper angles. The results were also supported with statistical analyses.

  4. The paradox of plows and productivity: an agronomic comparison of cereal grain production under Iroquois hoe culture and European plow culture in the seventeenth and eighteenth centuries.

    PubMed

    Mt Pleasant, Jane

    2011-01-01

    Iroquois maize farmers in the seventeenth and eighteenth centuries produced three to five times more grain per acre than wheat farmers in Europe. The higher productivity of Iroquois agriculture can be attributed to two factors. First, the absence of plows in the western hemisphere allowed Iroquois farmers to maintain high levels of soil organic matter, critical for grain yields. Second, maize has a higher yield potential than wheat because of its C4 photosynthetic pathway and lower protein content. However, tillage alone accounted for a significant portion of the yield advantage of the Iroquois farmers. When the Iroquois were removed from their territories at the end of the eighteenth century, US farmers occupied and plowed these lands. Within fifty years, maize yields in five counties of western New York dropped to less than thirty bushels per acre. They rebounded when US farmers adopted practices that countered the harmful effects of plowing. PMID:22180940

  5. Micromorphometric features of pore space in the plow horizons of loamy soils

    NASA Astrophysics Data System (ADS)

    Skvortsova, E. B.; Sanzharova, S. I.

    2007-04-01

    A computer-based analysis of thin sections has been applied to study pore space in the plow horizons of loamy soils in European Russia and Ukraine. Differences in the morphology of soil macro-and mesopores are shown. It is argued that agrogenic impacts result in the convergence of the shape and orientation of macropores in plowed loamy soils of the forest, forest-steppe, and steppe zones. At the same time, this convergence is not observed for the soil mesopores.

  6. Key performance indicators for electric mining shovels and oil sands diggability

    NASA Astrophysics Data System (ADS)

    Patnayak, Sibabrata

    A shovel performance monitoring study was undertaken in two oil sands mines operated by Syncrude Canada Ltd. using performance data obtained from P&H 4100 TS and BOSS electric mining shovels. One year of shovel performance data along with geological, geotechnical, and climatic data were analyzed. The approach adopted was to use current and voltage data collected from hoist and crowd motors and to calculate the energy and/or power associated with digging. Analysis of performance data along with digital video records of operating shovels indicated that hoist and crowd motor voltages and currents can be used to identify the beginning and the end of individual dig cycles. A dig cycle identification algorithm was developed. Performance indicators such as dig cycle time, hoist motor energy and power, and crowd motor energy and power were determined. The shovel performance indicators provide important insight into how geology, equipment and operators affect the digging efficiency. The hoist motor power is a useful key performance indicator for assessing diggability. Hoist motor energy consumption per tonne of material excavated and the number of dig cycles required for loading a truck can be useful key performance indicators for assessing operator performance and productivity. Analysis of performance data along with operators team schedules showed that the performance of a shovel can be significantly influenced by the operator's digging technique while digging uniform material. Up to 25% variability in hoist motor power consumption and 50% variability in productivity was noted between different operators. Shovel type and dipper teeth configuration can also influence the power draw on electrical motors during digging. There is no common agreement existing on the influence of bitumen content on oil sands diggability. By comparing the hoist motor power consumption, it was found that the rich ore was more difficult to dig than the lean ore. Similarly, estuarine ore was more

  7. Ethnic Association of Cusp of Carabelli Trait and Shoveling Trait in an Indian Population

    PubMed Central

    Manju, M; Praveen, R; Umesh, W

    2016-01-01

    Introduction Variations in the structure of teeth have always been of great interest to the dentist from the scientific as well as practical point of view. Additionally, ever since decades inter trait relationships have been a useful means to categorize populations to which an individual belongs. Aim To determine the association between Cusp of Carabelli and Shoveling Trait in a selected Indian population native of Bangalore city, Karnataka, India. Materials and Methods A cross-sectional study was carried out in 1885 children aged between 7-10 years. Casts of the study subjects were made to study the presence of Cusp of Carabelli of right maxillary permanent molar and shoveling trait of right maxillary permanent central incisor using the Dahlberg’s classification and Hrdliucka’s classification respectively. Linear regression was used to assess the association of cusp of carabelli trait with the tooth dimensions and logistic regression was used to evaluate the association of the carabelli trait with gender and presence/absence of shoveling. Results A 40.5% of subjects had Cusp of Carabelli on first molar and 68.2% had shoveling on upper central incisor. The study revealed positive association between the two traits studied in the population. A significant difference was also found with presence of Cusp of Carabelli and the buccolingual tooth dimension of the maxillary molar (p<0.05). Conclusion There is an association between the Cusp of Carabelli and the shoveling trait in the present study population, and this will be valuable in the determination of ethnic origin of an individual. PMID:27135008

  8. Birth and Evolution of Chiselling and Drilling Techniques for Removing Ear Canal Exostoses.

    PubMed

    Mudry, Albert; Hetzler, Douglas

    2016-01-01

    The main surgical techniques used to remove ear canal exostoses are drilling and/or, chiselling. The aim of this study was to identify the origins and subsequent evolution of, the surgical removal of ear canal exostoses in the 19th century. A critical review and, compilation of primary and secondary historical sources was conducted. Two techniques for removal of exostoses were developed in the latter part of the 19th century and have largely remained unchanged. This demonstrates the importance of that era in the history of ear surgery. PMID:26649611

  9. Delayed plowing of forages within potato rotation reduces nitrate leaching losses

    NASA Astrophysics Data System (ADS)

    Jiang, Y.; Jamieson, T.; Nyiraneza, J.; Somers, G.; Thompson, B.; Murray, B.; Grimmett, M.

    2013-12-01

    The potato industry plays an important role in the economics in Prince Edward Island (PEI), Canada. Intensive potato production has been conducted on sandy soil underlain by a semi-confined or unconfined sandstone aquifer, which provides all the drinking water and a large majority of stream flow on the island. Typically, potato is grown in rotation with grain underseeded with forages, with the latter being plowed down in the fall of the third season. High levels of nitrate leaching losses from the potato production systems have adversely affected both groundwater and associated surface water quality. Beneficial Management Practices (BMPs) were proposed for maintaining optimal crop production while mitigating the nitrate contamination in PEI. But there is limited information on the environmental performance of the BMPs in commercial fields. The potentials of delayed forage plowing from fall to spring to reduce nitrate losses were evaluated in commercial fields at two separated sites in PEI during October 2010 and March 2013. At Site 1, two tile-drained fields were paired for spring vs. fall plowing treatments (with pre-plow herbicidal treatment); weekly tile-drainage samples were collected to evidence the effects of the treatments. At Site 2, a field was split in half for spring vs. fall plowing treatments (without pre-plow herbicidal treatment). Shallow piezometers were installed at the upper and lower ends of the field for water sampling, with the upper end one indicating the effects of shallow groundwater inflow and the lower ones evidencing the combined effects of groundwater inflow and drainage from plowing treatments. Soil drainage was estimated through coupled LEACHN and MODFLOW simulations. Nitrate leaching losses were calculated as the integration of measured leached nitrate concentrations and simulated drainage. Field monitoring showed that nitrate leaching mainly occurred during the offseason. Nitrate leaching during the forage phase were estimated to be

  10. Generation of ultra-high magnetic fields by a degenerate, snow-plow pinch

    NASA Astrophysics Data System (ADS)

    Hartman, C. W.; Eddleman, J. L.; Gee, M.; Harte, J. A.; Zimmerman, G. B.

    1992-12-01

    We discuss 1-D and 2-D LASNEX calculations of a snow-plow pinch in Xenon. The pinch is driven by inductively stored energy, switched by a compact-torus, fast-opening switch, with performance characteristics calculated by the TRACII, 2-D, MHD code. The 10-cm initial radius, 1 cm long Xe pinch, is driven by 50 MA current thatis switched on in 100 ns. The pinch uniquely undergoes radiative collapse during the snow-plow phase, conforming to the original description of the 'snow-plow', to form a high-density, high-kinetic energy Xe shell which dynamically converges to a pinch equilibrium with degenerate electron pressure, high-density high-magnetic field. The described pinch configuration, calculated in 1-D, is expected to be unstable to R-T, sausage, and kink instabilities. A small initial B(sub zo) field (approximately 100 G) is calculated to be compressed to B(sub z) approximately = B (sub theta) at the final, degenerate, pinch equilibrium, thus stabilizing sausage instability. A larger initial B(sub z) field (approximately 10 kG) is calculated to be compressed by the radiatively collapsing plasma in the snow-plow to B(sub z) approximately = B (sub theta) to stabilize R-T instability during the snow-plow phase. Finally, the kink instability (if it occurs) is expected, as observed, to leave intact the tightly pinched plasma column.

  11. CARBON DIOXIDE AND NITROUS OXIDE FLUXES IN ORGANIC, NO-TILL AND CHISEL-TILL CROPPING SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic cropping systems may have the potential to increase soil C sequestration and reduce soil nitrous oxide (N2O) fluxes compared to conventional systems but organic systems are not well studied. We are measuring greenhouse gas fluxes and soil C sequestration in no-till, chisel-till and organic ...

  12. Progress report on the Pegasus plow, October--December 1996 and January--March 1997

    SciTech Connect

    1997-04-01

    This is a progress report on a contract related to the invention of a plow which will bury organic waste from farm fields, either in the form of shredded stubble or as whole stalks. The report addresses completion of various tasks in the contract, primarily related to field testing and trying to move the product into the market place.

  13. Simulating carbon sequestration in plowed and no-tillage systems in Brazilian Oxisols using CQESTR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    CQESTR simulates the effect of several management practices on soil organic carbon stocks. The model had been calibrated and validated in temperate regions. Our objective was to simulate carbon sequestration in Oxisols under plowed and no-tillage systems in northeastern and southeastern Brazil using...

  14. Molecular and phenotypic diversity in Chionactis occipitalis (Western Shovel-nosed Snake), with emphasis on the status of C. o. klauberi (Tucson Shovel-nosed Snake).

    USGS Publications Warehouse

    Wood, D.A.; Meik, J.M.; Holycross, A.T.; Fisher, R.N.; Vandergast, A.G.

    2008-01-01

    Chionactis occipitalis (Western Shovel-nosed Snake) is a small colubrid snake inhabiting the arid regions of the Mojave, Sonoran, and Colorado deserts. Morphological assessments of taxonomy currently recognize four subspecies. However, these taxonomic proposals were largely based on weak morphological differentiation and inadequate geographic sampling. Our goal was to explore evolutionary relationships and boundaries among subspecies of C. occipitalis, with particular focus on individuals within the known range of C. o. klauberi (Tucson Shovel-nosed snake). Population sizes and range for C. o. klauberi have declined over the last 25 years due to habitat alteration and loss prompting a petition to list this subspecies as endangered. We examined the phylogeography, population structure, and subspecific taxonomy of C. occipitalis across its geographic range with genetic analysis of 1100 bases of mitochondrial DNA sequence and reanalysis of 14 morphological characters from 1543 museum specimens. We estimated the species gene phylogeny from 81 snakes using Bayesian inference and explored possible factors influencing genetic variation using landscape genetic analyses. Phylogenetic and population genetic analyses reveal genetic isolation and independent evolutionary trajectories for two primary clades. Our data indicate that diversification between these clades has developed as a result of both historical vicariance and environmental isolating mechanisms. Thus these two clades likely comprise 'evolutionary significant units' (ESUs). Neither molecular nor morphological data are concordant with the traditional C. occipitalis subspecies taxonomy. Mitochondrial sequences suggest specimens recognized as C. o. klauberi are embedded in a larger geographic clade whose range has expanded from western Arizona populations, and these data are concordant with clinal longitudinal variation in morphology. ?? 2007 Springer Science+Business Media B.V.

  15. Reasons for service failure of an EKG-20 power shovel bogie wheel

    SciTech Connect

    Yakovleva, S.P.; Milokhin, S.E.

    1986-03-01

    In tests of experimental models of the EKG-20 power shovel in Neryungri Open Pit Coal Mine, regardless of the temperature of the atmosphere, cases of failure of the bogie wheels were observed. Metallographic and fractographic investigations of one such fragment with the use of methods of light and electron microscopy were conducted to reveal the reasons for the insufficient strength reserve of the wheels. The investigated wheel was produced from 60KhN steel. The authors found that failure of the bogie wheel occurs as a result of spalling.

  16. [Testing and commercialization of a cotton stalk shredder and plow]. Technical progress report, July--September, 1995

    SciTech Connect

    Thacker, G.W.

    1995-10-23

    The paper describes plans to field test several prototypes of plows that cut cotton stalks after harvesting and plows then back into the soil to prepare the field for the next planting. Modifications to the design have been made to allow the soil to more easily slide off the plow to reduce fuel consumption. A prototype has been shipped to Australia for testing in their fields and further product development. A farm machinery manufacturer has been selected to build two full-scale preproduction prototypes. Field testing will be done at sites in California and Arizona, since both have regulations specifying that cotton stalks must be shredded.

  17. Nanostructured wear resistant coating for reversible cultivator shovels: An experimental investigation

    NASA Astrophysics Data System (ADS)

    Dave, V.; Rao, G. P.; Tiwari, G. S.; Sanger, A.; Kumar, A.; Chandra, R.

    2016-04-01

    Cultivator, one of the agriculture farm tool, extensively suffers from the wear problem. In this paper, we report nanostructured chromium nitrite (CrN) coating for the cultivator shovels to mitigate wear problem. The (CrN) coating was developed using DC magnetron sputtering technique at 200 °C. The structural, morphological, hydrophobic and wear properties were investigated using X-ray diffractometer, scanning electron microscope, contact angle goniometer and custom designed soil bin assembly. The XRD reveals that the deposited coating was polycrystalline in nature with cubic structure. Also, The deposited coating was found to be anti wear resistant as well as hydrophobic in nature. The gravimetric wear for the coating developed at 200 °C coated was found out to be 8.15 gm and for non coated it was 14.48 gm tested for 100 hrs. The roughness of the coating plays an important role in determining the hydrophobicity of the coated film. Roughness and contact angle measured for 200 °C coated shovel was found out to be 11.17 nm and 105 ° respectively.

  18. Continuous dental replacement in a hyper-chisel tooth digging rodent

    PubMed Central

    Gomes Rodrigues, Helder; Marangoni, Pauline; Šumbera, Radim; Tafforeau, Paul; Wendelen, Wim; Viriot, Laurent

    2011-01-01

    Contrary to their reptilian ancestors, which had numerous dental generations, mammals are known to usually develop only two generations of teeth. However, a few mammal species have acquired the ability to continuously replace their dentition by the constant addition of supernumerary teeth moving secondarily toward the front of the jaw. The resulting treadmill-like replacement is thus horizontal, and differs completely from the vertical dental succession of other mammals and their extinct relatives. Despite the developmental implications and prospects regarding the origin of supernumerary teeth, this striking innovation remains poorly documented. Here we report another case of continuous dental replacement in an African rodent, Heliophobius argenteocinereus, which combines this dental system with the progressive eruption of high-crowned teeth. The escalator-like mechanism of Heliophobius constitutes an original adaptation to hyper-chisel tooth digging involving high dental wear. Comparisons between Heliophobius and the few mammals that convergently acquired continuous dental replacement reveal that shared inherited traits, including dental mesial drift, delayed eruption, and supernumerary molars, comprise essential prerequisites to setting up this dental mechanism. Interestingly, these dental traits are present to a lesser extent in humans but are absent in mouse, the usual biological model. Consequently, Heliophobius represents a suitable model to investigate the molecular processes leading to the development of supernumerary teeth in mammals, and the accurate description of these processes could be a significant advance for further applications in humans, such as the regeneration of dental tissues. PMID:21987823

  19. Solid Lubrication Fundamentals and Applications. Chapter 5; Abrasion: Plowing and Cutting

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    2001-01-01

    Chapter 5 discusses abrasion, a common wear phenomenon of great economic importance. It has been estimated that 50% of the wear encountered in industry is due to abrasion. Also, it is the mechanism involved in the finishing of many surfaces. Experiments are described to help in understanding the complex abrasion process and in predicting friction and wear behavior in plowing and/or cutting. These experimental modelings and measurements used a single spherical pin (asperity) and a single wedge pin (asperity). Other two-body and three-body abrasion studies used hard abrasive particles.

  20. Mechanical-plowing-based high-speed patterning on hard material via advanced-control and ultrasonic probe vibration

    SciTech Connect

    Wang, Zhihua; Zou, Qingze; Tan, Jun; Jiang, Wei

    2013-11-15

    In this paper, we present a high-speed direct pattern fabrication on hard materials (e.g., a tungsten-coated quartz substrate) via mechanical plowing. Compared to other probe-based nanolithography techniques based on chemical- and/or physical-reactions (e.g., the Dip-pen technique), mechanical plowing is meritorious for its low cost, ease of process control, and capability of working with a wide variety of materials beyond conductive and/or soft materials. However, direct patterning on hard material faces two daunting challenges. First, the patterning throughput is ultimately hindered by the “writing” (plowing) speed, which, in turn, is limited by the adverse effects that can be excited/induced during high-speed, and/or large-range plowing, including the vibrational dynamics of the actuation system (the piezoelectric actuator, the cantilever, and the mechanical fixture connecting the cantilever to the actuator), the dynamic cross-axis coupling between different axes of motion, and the hysteresis and the drift effects related to the piezoelectric actuators. Secondly, it is very challenging to directly pattern on ultra-hard materials via plowing. Even with a diamond probe, the line depth of the pattern via continuous plowing on ultra-hard materials such as tungsten, is still rather small (<0.5 nm), particularly when the “writing” speed becomes high. To overcome these two challenges, we propose to utilize a novel iterative learning control technique to achieve precision tracking of the desired pattern during high-speed, large-range plowing, and introduce ultrasonic vibration of the probe in the normal (vertical) direction during the plowing process to enable direct patterning on ultra hard materials. The proposed approach was implemented to directly fabricate patterns on a mask with tungsten coating and quartz substrate. The experimental results demonstrated that a large-size pattern of four grooves (20 μm in length with 300 nm spacing between lines) can be

  1. Mechanical-plowing-based high-speed patterning on hard material via advanced-control and ultrasonic probe vibration

    NASA Astrophysics Data System (ADS)

    Wang, Zhihua; Tan, Jun; Zou, Qingze; Jiang, Wei

    2013-11-01

    In this paper, we present a high-speed direct pattern fabrication on hard materials (e.g., a tungsten-coated quartz substrate) via mechanical plowing. Compared to other probe-based nanolithography techniques based on chemical- and/or physical-reactions (e.g., the Dip-pen technique), mechanical plowing is meritorious for its low cost, ease of process control, and capability of working with a wide variety of materials beyond conductive and/or soft materials. However, direct patterning on hard material faces two daunting challenges. First, the patterning throughput is ultimately hindered by the "writing" (plowing) speed, which, in turn, is limited by the adverse effects that can be excited/induced during high-speed, and/or large-range plowing, including the vibrational dynamics of the actuation system (the piezoelectric actuator, the cantilever, and the mechanical fixture connecting the cantilever to the actuator), the dynamic cross-axis coupling between different axes of motion, and the hysteresis and the drift effects related to the piezoelectric actuators. Secondly, it is very challenging to directly pattern on ultra-hard materials via plowing. Even with a diamond probe, the line depth of the pattern via continuous plowing on ultra-hard materials such as tungsten, is still rather small (<0.5 nm), particularly when the "writing" speed becomes high. To overcome these two challenges, we propose to utilize a novel iterative learning control technique to achieve precision tracking of the desired pattern during high-speed, large-range plowing, and introduce ultrasonic vibration of the probe in the normal (vertical) direction during the plowing process to enable direct patterning on ultra hard materials. The proposed approach was implemented to directly fabricate patterns on a mask with tungsten coating and quartz substrate. The experimental results demonstrated that a large-size pattern of four grooves (20 μm in length with 300 nm spacing between lines) can be

  2. Comparative ability of northern pintails, gadwalls, and northern shovelers to metabolize foods

    USGS Publications Warehouse

    Miller, M.R.

    1984-01-01

    Feeding trials were used to compare the ability of northern pintails (Anas acuta), gadwalls (A. strepera), and northern shovelers (A. clypeata) to metabolize energy from a turkey starter ration, alfalfa pellets, and common barnyardgrass (Echinochloa crusgalli) seeds. No differences (P > 0.05) were detected among the three species for any of the three foods (kg body weight/day basis), for dry matter intake (DMI), body weight gain (BWG), apparent metabolizable energy (AME), or metabolized energy (MEE) on any given diet consumed in quantities large enough to promote body weight gain. The AME content of alfalfa was 57% less than the value for turkey starter and 50% less than for barnyardgrass seeds. All three species metabolized more energy and gained weight faster when fed turkey starter. Energy modeling may be facilitated if additional research verifies that all species of dabbling ducks have equal ability to obtain energy from foods available to them in the wild. Behavioral and morphological factors may be more important in defining feeding niches than digestive physiology, at least for the three duck species tested, at the time of year of the experiments, and within the limits of the quality of foods used.

  3. Derivation of soil screening thresholds to protect chisel-toothed kangaroo rat from uranium mine waste in northern Arizona

    USGS Publications Warehouse

    Hinck, Jo E.; Linder, Greg L.; Otton, James K.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.

    2013-01-01

    Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes.

  4. Evaluation of stereoscopic video cameras synchronized with the movement of an operator's head on the teleoperation of the actual backhoe shovel

    NASA Astrophysics Data System (ADS)

    Minamoto, Masahiko; Matsunaga, Katsuya

    1999-05-01

    Operator performance while using a remote controlled backhoe shovel is described for three different stereoscopic viewing conditions: direct view, fixed stereoscopic cameras connected to a helmet mounted display (HMD), and rotating stereo camera connected and slaved to the head orientation of a free moving stereo HMD. Results showed that the head- slaved system provided the best performance.

  5. Investigation of the influence of mallet and chisel techniques on the lingual fracture line and comparison with the use of splitter and separators during sagittal split osteotomy in cadaveric pig mandibles.

    PubMed

    Verweij, Jop P; Mensink, Gertjan; Houppermans, Pascal N W J; Frank, Michael D; van Merkesteyn, J P Richard

    2015-04-01

    In bilateral sagittal split osteotomy the proximal and distal segments of the mandible are traditionally separated using chisels. Modern modifications include prying and spreading the segments with splitters. This study investigates the lingual fracture patterns and status of the nerve after sagittal split osteotomy (SSO) using the traditional chisel technique and compares these results with earlier studies using the splitter technique. Lingual fractures after SSO in cadaveric pig mandibles were analysed using a lingual split scale and split scoring system. Iatrogenic damage to the inferior alveolar nerve was assessed. Fractures started through the caudal cortex more frequently in the chisel group. This group showed more posterior lingual fractures, although this difference was not statistically significant. Nerve damage was present in three cases in the chisel group, but was not observed in the splitter group. A trend was apparent, that SSO using the chisel technique instead of the splitter technique resulted in more posterior lingual fracture lines, although this difference was not statistically significant. Both techniques resulted in reliable lingual fracture patterns. Splitting without chisels could prevent nerve damage, therefore we propose a spreading and prying technique with splitter and separators. However, caution should be exercised when extrapolating these results to the clinic. PMID:25697050

  6. Spatial variability of detrended soil plow layer penetrometer resistance transect in a sugarcane field

    NASA Astrophysics Data System (ADS)

    Pérez, Luis D.; Cumbrera, Ramiro; Mato, Juan; Millán, Humberto; Tarquis, Ana M.

    2015-04-01

    Spatial variability of soil properties is relevant for identifying those zones with physical degradation. In this sense, one has to face the problem of identifying the origin and distribution of spatial variability patterns (Brouder et al., 2001; Millán et al., 2012). The objective of the present work was to quantify the spatial structure of soil penetrometer resistance (PR) collected from a transect data consisted of 221 points equidistant. In each sampling, readings were obtained from 0 cm till 70 cm of depth, with an interval of 5 cm (Pérez, 2012). The study was conducted on a Vertisol (Typic Hapludert) dedicated to sugarcane (Saccharum officinarum L.) production during the last sixty years (Pérez et al., 2010). Recently, scaling approach has been applied on the determination of the scaling data properties (Tarquis et al., 2008; Millán et al., 2012; Pérez, 2012). We focus in the Hurst analysis to characterize the data variability for each depth. Previously a detrended analysis was conducted in order to better study de intrinsic variability of the series. The Hurst exponent (H) for each depth was estimated showing a characteristic pattern and differentiating PR evolution in depth. References Brouder, S., Hofmann, B., Reetz, H.F., 2001. Evaluating spatial variability of soil parameters for input management. Better Crops 85, 8-11. Millán, H; AM Tarquís, Luís D. Pérez, Juan Mato, Mario González-Posada, 2012. Spatial variability patterns of some Vertisol properties at a field scale using standardized data. Soil and Tillage Research, 120, 76-84. Pérez, Luís D. 2012. Influencia de la maquinaria agrícola sobre la variabilidad espacial de la compactación del suelo. Aplicación de la metodología geoestadística-fractal. PhD thesis, UPM (In Spanish). Pérez, Luís D., Humberto Millán, Mario González-Posada 2010. Spatial complexity of soil plow layer penetrometer resistance as influenced by sugarcane harvesting: A prefractal approach. Soil and Tillage

  7. Health Hazard Evaluation Report HETA-80-073-1589, Marion Power Shovel, Marion, Ohio. [Core and mold areas (MDI binders)

    SciTech Connect

    Stephenson, R.L.; Liss, G.M.

    1985-04-01

    Environmental and breathing-zone samples were analyzed for methylene-bisphenyl-isocyanate (MDI), total reactive isocyanate groups (TRIG), triethylamine, mineral spirits, and metal fume at Marion Power Shovel Foundry, Marion, Ohio, in March and September, 1983. The evaluation was requested by the union to assess exposures in the core and mold areas where MDI binders were used. Interviews were conducted with 26 exposed and 13 nonexposed workers. Medical examinations that included pulmonary function and immunological testing, and chest x-rays were administered. All exposures were below the OSHA standards for TRIG. Previously obtained silica monitoring data was reviewed. Silica overexposure was indicated. Twenty-seven exposed workers reported lower respiratory tract symptoms consistent with occupational asthma. The authors conclude that significant exposures to isocyanates have occurred at the facility. A health hazard due to silica also exists. Recommendations include establishing a medical surveillance program for MDI and reducing silica exposures by appropriate engineering controls.

  8. Changes in the soils of solonetzic associations in 30 years after their reclamation with the use of moldboard plowing, deep tillage with a three-tier plow, and deep rotary tillage

    NASA Astrophysics Data System (ADS)

    Kalinichenko, V. P.; Sharshak, V. K.; Bezuglova, O. S.; Ladan, E. P.; Genev, E. D.; Illarionov, V. V.; Zinchenko, V. E.; Morkovskoi, N. A.; Chernenko, V. V.; Il'Ina, L. P.

    2011-08-01

    Changes in the properties of solonetzic soil associations (chestnut solonetzic soils and chestnut solonetzes) in the dry steppe after their reclamation have been studied for 30 years. The reclamation included the deep three-tier plowing and the approach of rotary tillage. A single rotary tillage operation resulted in the formation of fine aggregates of equal sizes in the plow layer; any morphological features of the restoration of solonetzic pedogenesis are absent. The atmospheric moisture easily penetrates into the soil, and soluble salts are leached off to a great depth. In 30 years since the soil amelioration with the use of a PMS-70 rotary tiller, the humus content has increased up to 3.3% in the upper 20-cm-thick layer and up to 2.4% in the layer of 20-40 cm. The content of adsorbed Na+ in the 20- to 30-cm-thick layer has decreased to 10.6% of the cation exchange capacity (in comparison with 19.8% in the nonreclaimed soil). The spatial heterogeneity of the soil cover has decreased in comparison with that prior to the reclamation. During the entire observation period, crop yields gained from the fields reclaimed with the use of the rotary tiller have been by 25-60% higher in comparison with those on the fields with traditional treatments.

  9. Bioavailability of metals and toxicity identification of the sediment pore waters from Plow Shop Pond, Fort Devens, Massachusetts

    SciTech Connect

    Jop, K.; Putt, A.; Shepherd, S.; Askew, A.; Bleiler, J.; Reed, S.; George, C.

    1995-12-31

    Plow Shop Pond is a shallow, 30-acre pond located at Fort Devens, Massachusetts. An ecological risk assessment was conducted at Plow Shop Pond as part of a remedial investigation. Preliminary analysis revealed high concentrations of arsenic, copper, chromium, lead, and mercury in the sediment. Therefore, a laboratory testing program was incorporated into this investigation to assess the toxicity of sediments to aquatic organisms. The screening testing program included short-term chronic exposure of Ceriodaphnia dubia to pore waters, 10-day exposures of Chironomus tentans and Hyalella azteca to bulk sediments and a bioaccumulation study with Lumbriculus variegatus. Survival and reproduction of C. dubia, growth of amphipods and reproduction of oligochaetes appeared to indicate sediment toxicity at some sites within the pond. Although high concentrations of arsenic, copper, mercury and lead were detected in the whole sediments and pore waters, the response could not be correlated to a particular element. Also, relatively low bioaccumulation of methyl mercury and high uptake of inorganic mercury was established for three sediment samples. To characterize and identify the source of toxicity, a toxicity identification evaluation program using sediments collected at several locations was performed. The pore water from these samples was used for fractionation coupled with a 10-day test using H. azteca. Survival and growth were evaluated as endpoints during the exposures. Partitioning of metals and their bioavailability was influenced primarily by organic carbon and AVS concentration. At least two constituents were responsible for the toxicity.

  10. Development of a portable teleoperated robot for the manipulation of a backhoe shovel for the restoration of disaster-stricken sites

    NASA Astrophysics Data System (ADS)

    Tanaka, Toshihiko; Sakai, Yosiharu; Konomi, Yosiyuki; Chayama, Kazuhiro; Minamoto, Masahiko; Matsunaga, Katsuya

    1999-11-01

    Restoration activities after disasters such as landslides or rock avalanches require rapid action, but in fact, in most cases these activities are very inefficient because of the danger of secondary disasters. A system which can operate reconstruction machinery by remote control was therefore developed, and it was installed on general-purpose construction machines (backhoe shovels). Control performance experiments and field experiments on this developed system were carried out, and its effectiveness was confirmed.

  11. ChISELS 1.0: theory and user manual :a theoretical modeler of deposition and etch processes in microsystems fabrication.

    SciTech Connect

    Plimpton, Steven James; Schmidt, Rodney Cannon; Ho, Pauline; Musson, Lawrence Cale

    2006-09-01

    Chemically Induced Surface Evolution with Level-Sets--ChISELS--is a parallel code for modeling 2D and 3D material depositions and etches at feature scales on patterned wafers at low pressures. Designed for efficient use on a variety of computer architectures ranging from single-processor workstations to advanced massively parallel computers running MPI, ChISELS is a platform on which to build and improve upon previous feature-scale modeling tools while taking advantage of the most recent advances in load balancing and scalable solution algorithms. Evolving interfaces are represented using the level-set method and the evolution equations time integrated using a Semi-Lagrangian approach [1]. The computational meshes used are quad-trees (2D) and oct-trees (3D), constructed such that grid refinement is localized to regions near the surface interfaces. As the interface evolves, the mesh is dynamically reconstructed as needed for the grid to remain fine only around the interface. For parallel computation, a domain decomposition scheme with dynamic load balancing is used to distribute the computational work across processors. A ballistic transport model is employed to solve for the fluxes incident on each of the surface elements. Surface chemistry is computed by either coupling to the CHEMKIN software [2] or by providing user defined subroutines. This report describes the theoretical underpinnings, methods, and practical use instruction of the ChISELS 1.0 computer code.

  12. Macrophages lift off surface-bound bacteria using a filopodium-lamellipodium hook-and-shovel mechanism

    PubMed Central

    Möller, Jens; Lühmann, Tessa; Chabria, Mamta; Hall, Heike; Vogel, Viola

    2013-01-01

    To clear pathogens from host tissues or biomaterial surfaces, phagocytes have to break the adhesive bacteria-substrate interactions. Here we analysed the mechanobiological process that enables macrophages to lift-off and phagocytose surface-bound Escherichia coli (E. coli). In this opsonin-independent process, macrophage filopodia hold on to the E. coli fimbriae long enough to induce a local protrusion of a lamellipodium. Specific contacts between the macrophage and E. coli are formed via the glycoprotein CD48 on filopodia and the adhesin FimH on type 1 fimbriae (hook). We show that bacterial detachment from surfaces occurrs after a lamellipodium has protruded underneath the bacterium (shovel), thereby breaking the multiple bacterium-surface interactions. After lift-off, the bacterium is engulfed by a phagocytic cup. Force activated catch bonds enable the long-term survival of the filopodium-fimbrium interactions while soluble mannose inhibitors and CD48 antibodies suppress the contact formation and thereby inhibit subsequent E. coli phagocytosis. PMID:24097079

  13. Comparison of impacts on macroinvertebrates and fish from gas pipeline installation by wet-ditching and plowing

    SciTech Connect

    Vinikour, W.S.; Schubert, J.P.; Gartman, D.K.

    1987-01-01

    Biotic effects from wet-ditching were investigated at the Little Miami River, Ohio. Invertebrate densities decreased at, and a short distance below, the crossing site; partial benthic recolonization occurred within three weeks of construction, while complete recolonization occurred within seven months. Fish recolonized the affected area within one month, but densities were reduced; within eight months after construction, the fish community was similar to that observed before construction. Biotic effects from the plow method were examined at Canada Creek, Michigan. No significant impacts on benthic macroinvertebrates were detected. During ramp excavation, increased macroinvertebrate drift densities were noted, as well as increased occurrence of terrestrial invertebrates in the drift; upon completion of ramp excavation, drift composition approximated that before construction. No effects on fish species were indicated. Overall, no biotic impacts were detected within three days after pipeline installation. 23 refs., 4 figs., 3 tabs.

  14. Fuzzy Boundaries: Color and Gene Flow Patterns among Parapatric Lineages of the Western Shovel-Nosed Snake and Taxonomic Implication

    PubMed Central

    Wood, Dustin A.; Fisher, Robert N.; Vandergast, Amy G.

    2014-01-01

    Accurate delineation of lineage diversity is increasingly important, as species distributions are becoming more reduced and threatened. During the last century, the subspecies category was often used to denote phenotypic variation within a species range and to provide a framework for understanding lineage differentiation, often considered incipient speciation. While this category has largely fallen into disuse, previously recognized subspecies often serve as important units for conservation policy and management when other information is lacking. In this study, we evaluated phenotypic subspecies hypotheses within shovel-nosed snakes on the basis of genetic data and considered how evolutionary processes such as gene flow influenced possible incongruence between phenotypic and genetic patterns. We used both traditional phylogenetic and Bayesian clustering analyses to infer range-wide genetic structure and spatially explicit analyses to detect possible boundary locations of lineage contact. Multilocus analyses supported three historically isolated groups with low to moderate levels of contemporary gene exchange. Genetic data did not support phenotypic subspecies as exclusive groups, and we detected patterns of discordance in areas where three subspecies are presumed to be in contact. Based on genetic and phenotypic evidence, we suggested that species-level diversity is underestimated in this group and we proposed that two species be recognized, Chionactis occipitalis and C. annulata. In addition, we recommend retention of two subspecific designations within C. annulata (C. a. annulata and C. a. klauberi) that reflect regional shifts in both genetic and phenotypic variation within the species. Our results highlight the difficultly in validating taxonomic boundaries within lineages that are evolving under a time-dependent, continuous process. PMID:24848638

  15. Fuzzy boundaries: color and gene flow patterns among parapatric lineages of the western shovel-nosed snake and taxonomic implication

    USGS Publications Warehouse

    Wood, Dustin A.; Fisher, Robert N.; Vandergast, Amy G.

    2014-01-01

    Accurate delineation of lineage diversity is increasingly important, as species distributions are becoming more reduced and threatened. During the last century, the subspecies category was often used to denote phenotypic variation within a species range and to provide a framework for understanding lineage differentiation, often considered incipient speciation. While this category has largely fallen into disuse, previously recognized subspecies often serve as important units for conservation policy and management when other information is lacking. In this study, we evaluated phenotypic subspecies hypotheses within shovel-nosed snakes on the basis of genetic data and considered how evolutionary processes such as gene flow influenced possible incongruence between phenotypic and genetic patterns. We used both traditional phylogenetic and Bayesian clustering analyses to infer range-wide genetic structure and spatially explicit analyses to detect possible boundary locations of lineage contact. Multilocus analyses supported three historically isolated groups with low to moderate levels of contemporary gene exchange. Genetic data did not support phenotypic subspecies as exclusive groups, and we detected patterns of discordance in areas where three subspecies are presumed to be in contact. Based on genetic and phenotypic evidence, we suggested that species-level diversity is underestimated in this group and we proposed that two species be recognized, Chionactis occipitalis and C. annulata. In addition, we recommend retention of two subspecific designations within C. annulata (C. a. annulata and C. a. klauberi) that reflect regional shifts in both genetic and phenotypic variation within the species. Our results highlight the difficultly in validating taxonomic boundaries within lineages that are evolving under a time-dependent, continuous process.

  16. Derivation of soil-screening thresholds to protect the chisel-toothed kangaroo rat from uranium mine waste in northern Arizona.

    PubMed

    Hinck, Jo Ellen; Linder, Greg; Otton, James K; Finger, Susan E; Little, Edward; Tillitt, Donald E

    2013-08-01

    Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes. PMID:23604138

  17. Spatial and temporal soil water variability in the plowing horizon of agriculturally used soils in two regions of Southwest Germany

    NASA Astrophysics Data System (ADS)

    Poltoradnev, Maxim; Ingwersen, Joachim; Streck, Thilo

    2015-04-01

    Soil water dynamics plays an important role in soil-plant-atmosphere interactions. There is a lack of long-term continuous measurements of topsoil water content at the regional scale. The objective of the present study was to quantify and elucidate the seasonal dynamics of spatial soil water content variability in the plowing horizon (Ap) of agricultural soils at the regional scale. The study was conducted in the central part of the Kraichgau and the Mid Swabian Alb in Southwest Germany. In each region a soil water network embracing 21 stations was set up. All stations were installed on cropped agricultural sites and distributed across three spatial domains: an inner domain 3 km × 3 km (5 stations), a middle 9 km × 9 km (8 stations), and an outer domain 27 km × 27 km (8 stations). Each station consists of a TDT sensor (SI.99 Aquaflex Soil Moisture Sensor, Streat Instruments Ltd, New Zealand), which senses both soil water content and soil temperature, a rain gauge, and a remote transfer unit (RTU, datalogger + GSM modem), which stores and transfers data via GPRS modem to the central data server (Adcon Telemetry GmbH, Austria) located at the University of Hohenheim. The TDT sensors were installed at 0.15 m depth. A sensor consists of a three meter long and three centimeter wide flat transmission line. The relationship between the standard deviation (σθ) of the soil water content (SWC) and mean spatial soil water content (<θ>) formed combinations of concave and convex hyperbolas. However, it strongly depended on SWC state and season. Generally, σθ was found to be changing along a convex trend during dry out and rewetting phases with a maximum in the intermediate SWC range. At the rain event scale, σθ(<θ>) was either ascending or converging with decreasing <θ>. A concave shape was observed when <θ> approached to dry state. The majority of σθ(<θ>) hysteresis loops were observed in intermediate and intermediate/wet state of SWC. All hysteretic loops were

  18. The formation of the agrogenic typical chernozem profile in the Ukrainian forest-steppe after plowing virgin steppe and fallow soils

    NASA Astrophysics Data System (ADS)

    Nosko, B. S.

    2013-03-01

    The data on the changes in the physicochemical, biological, and agrochemical properties of a loamy-clayey typical chernozem after plowing a 40-year-old Fallow (for six cycles of a cereal-beet rotation) and a sandy-loamy typical chernozem (for eighteen cycles of a five-course rotation) under different intensities of their use are presented. The major role of the mineral and organic fertilizers and the methods of their application have been revealed in the formation of the humus profile, the acid-base characteristics, and the agrophysical and agrochemical properties.

  19. Influence of the Plow Filling and Thread Angle onto the Plow Head Efficiency / Wpływ Współczynnika Wypełnienia Organu Oraz Kąta Nawinięcia Płata Ślimaka Na Sprawność Ładowania Frezującymi Organami Ślimakowymi

    NASA Astrophysics Data System (ADS)

    Wydro, Tomasz

    2015-03-01

    Laboratory examinations on the plow heads at various filling rate and material grain-size, as well as various values of worm thread angle of the plow head have been executed. Influence of the worm thread angle and plow head filling onto optimal loading efficiency, has also been tested. Eksploatacja węgla kamiennego w Polsce odbywa się przy zastosowaniu kompleksów ścianowych kombajnowych jak również kompleksów strugowych. Ten drugi z kompleksów jest znacznie mniej rozpowszechniony w Polsce i stosowany do pokładów o miąższości poniżej 1,5 m. Do głównych maszyn i urządzeń ścianowego kompleksu kombajnowego należy zaliczyć maszynę urabiająco - ładującą jaką jest kombajn ścianowy, obudowę zmechanizowaną oraz przenośnik ścianowy. Elementami roboczymi w kombajnie ścianowym są frezujące organy ślimakowe, które mocowane są na ramionach kombajnu. Zadaniem frezujących organów ślimakowych jest realizacja jednocześnie dwóch procesów. Pierwszym z procesów jest frezowanie czyli oddzielanie kawałków węgla od calizny. Drugi proces to proces ładowania urobku, polegający na ciągłym odprowadzaniu urobku na przenośnik ścianowy. Równoległość realizacji pracy tych dwóch procesów, uniemożliwia w warunkach rzeczywistych przeprowadzenie obserwacji procesu ładowania i dokonania jakichkolwiek pomiarów i analiz. Dlatego też, przeprowadzane badania i pomiary opisywane w literaturze zwykle miały charakter modelowy lub stanowiskowy, gdyż tylko takie warunki umożliwiały rozdział tych funkcji organu (Chodura, 1992; Hyong Jong Gol, 1990; Jaszczuk & Tomaszewski, 2004; Krauze, 1997). W związku z powyższym, chcąc bliżej poznać prawa rządzące procesem ładowania, zdecydowano się na rozdzielenie tych dwóch procesów i przeprowadzenie badań laboratoryjnych. Przedmiotowe badania zostały przeprowadzone w laboratorium Katedry Maszyn Górniczych, Przeróbczych i Transportowych AGH. W badaniach uwzgl

  20. 29 CFR 553.24 - “Public safety”, “emergency response”, and “seasonal” activities.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for several weeks on a special project or assigned to an afternoon of shoveling snow off the..., may have significant periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may be able to accrue compensatory time to...

  1. 29 CFR 553.24 - “Public safety”, “emergency response”, and “seasonal” activities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for several weeks on a special project or assigned to an afternoon of shoveling snow off the..., may have significant periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may be able to accrue compensatory time to...

  2. TILLAGE EROSION: TERRACE RELATIONSHIPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All tillage moves soil. Implements drawn by animals or a tractor move soil in the direction of travel and, to a lesser extent, sideways. While a moldboard plow throws soil to only one side, most tillage implements—including tandem disks, chisel plows, harrows, and cultivators—throw soil to both side...

  3. Thirty-year tillage effects on crop yield and soil fertility indicators

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Long-term studies are crucial for quantifying tillage system effects on crop productivity and soil fertility status. We examined 30 years of data for five tillage systems evaluated on two glacial till soils in central Iowa, USA from 1975 through 2006. Moldboard plow, chisel plow, spring disk, ridge-...

  4. Tillage and rotation effect on corn - soybean energy balances in eastern Nebraska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Data from a field experiment conducted in eastern Nebraska over 16 yr (1986-2001) were used to determine the energy balance of corn (Zea mays L.) and soybean (Glycine max L.) as affected by tillage treatments and rotation. Tillage treatments included chisel plow, tandom disk, moldboard plow, ridge-t...

  5. Influence of the Plow Filling and Thread Angle onto the Plow Head Efficiency / Wpływ Współczynnika Wypełnienia Organu Oraz Kąta Nawinięcia Płata Ślimaka Na Sprawność Ładowania Frezującymi Organami Ślimakowymi

    NASA Astrophysics Data System (ADS)

    Wydro, Tomasz

    2015-03-01

    Laboratory examinations on the plow heads at various filling rate and material grain-size, as well as various values of worm thread angle of the plow head have been executed. Influence of the worm thread angle and plow head filling onto optimal loading efficiency, has also been tested. Eksploatacja węgla kamiennego w Polsce odbywa się przy zastosowaniu kompleksów ścianowych kombajnowych jak również kompleksów strugowych. Ten drugi z kompleksów jest znacznie mniej rozpowszechniony w Polsce i stosowany do pokładów o miąższości poniżej 1,5 m. Do głównych maszyn i urządzeń ścianowego kompleksu kombajnowego należy zaliczyć maszynę urabiająco - ładującą jaką jest kombajn ścianowy, obudowę zmechanizowaną oraz przenośnik ścianowy. Elementami roboczymi w kombajnie ścianowym są frezujące organy ślimakowe, które mocowane są na ramionach kombajnu. Zadaniem frezujących organów ślimakowych jest realizacja jednocześnie dwóch procesów. Pierwszym z procesów jest frezowanie czyli oddzielanie kawałków węgla od calizny. Drugi proces to proces ładowania urobku, polegający na ciągłym odprowadzaniu urobku na przenośnik ścianowy. Równoległość realizacji pracy tych dwóch procesów, uniemożliwia w warunkach rzeczywistych przeprowadzenie obserwacji procesu ładowania i dokonania jakichkolwiek pomiarów i analiz. Dlatego też, przeprowadzane badania i pomiary opisywane w literaturze zwykle miały charakter modelowy lub stanowiskowy, gdyż tylko takie warunki umożliwiały rozdział tych funkcji organu (Chodura, 1992; Hyong Jong Gol, 1990; Jaszczuk & Tomaszewski, 2004; Krauze, 1997). W związku z powyższym, chcąc bliżej poznać prawa rządzące procesem ładowania, zdecydowano się na rozdzielenie tych dwóch procesów i przeprowadzenie badań laboratoryjnych. Przedmiotowe badania zostały przeprowadzone w laboratorium Katedry Maszyn Górniczych, Przeróbczych i Transportowych AGH. W badaniach uwzgl

  6. Dirty Oil and Shovel-Ready Jobs

    ERIC Educational Resources Information Center

    Mac Phail, Abby

    2012-01-01

    In this article, the author describes a role-playing activity on tar sands and the proposed TransCanada Keystone XL pipeline. In this activity, students take on the characters of six key stakeholders invited to an imaginary public hearing to discuss whether or not the State Department and President Obama should approve the Keystone XL pipeline.…

  7. Site Tamper and Material Plow Tool - STAMP

    NASA Technical Reports Server (NTRS)

    Aisen, Norman M.; Collins, Curtis L.; Trebi-Ollennu, Ashitey

    2012-01-01

    A non-actuated tool has been developed for preparing regolith for in situ measurement by smoothing uneven surfaces and excavating fresher subsurface material for planetary exploration. The STAMP tool contains two tools to prepare regolith for in situ measurement: a tamper to smooth uneven surfaces, and a blade to excavate fresher subsurface material.

  8. AmeriFlux US-Ro3 Rosemount- G19

    SciTech Connect

    Baker, John; Griffis, Tim

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ro3 Rosemount- G19. Site Description - This tower is located in a farm field farmed in accordance with the cominant farming practice in the region: a corn/soybean rotation with chisel plow tillage in the fall following corn harvest and in the spring following soybeans.

  9. AmeriFlux US-Ro1 Rosemount- G21

    SciTech Connect

    Baker, John; Griffis, Tim; Griffis, Timothy

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ro1 Rosemount- G21. Site Description - This tower is located in a farm field farmed in accordance with the dominant farming practice in the region: a corn/soybean rotation with chisel plow tillage in the fall following corn harvest and in the spring following soybeans.

  10. Transport and persistence of tylosin-resistant enterococci, erm genes, and tylosin in soil and drainage water from fields receiving swine manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land application of manure from tylosin-treated swine introduces tylosin-resistant enterococci, erm genes, which confer resistance to tylosin, and tylosin. This study documents the occurrence and transport of tylosin-resistant enterococci, erm genes, and tylosin in tile-drained chisel plow and no-ti...

  11. Anticipating Stimulus Money for Campus Projects, Colleges Get "Shovel Ready"

    ERIC Educational Resources Information Center

    Carlson, Scott

    2009-01-01

    Help for colleges may be on the way in the $825-billion stimulus package being pressed by Congressional leaders. The bill that House Democrats introduced this month includes $7-billion for higher-education modernization, renovation, and repair that could kick-start projects like upgrading heating and cooling systems, fixing roofs, and doing…

  12. Evaluation of a new tillage tool; considering soil physical property, energy requirement and potato yield.

    PubMed

    Ghazavi, M A

    2007-11-15

    Two series of field experiments were conducted for this comparison study, one in the UK and the second in Iran. First, the effects of each implement on the soil structure were investigated. Then these implements were used in the preparation of a potato seedbed for a final evaluation. Soil physical changes were measured including soil aggregate size analysis, cone penetrometer resistance, bulk density, surface relief and soil moisture content before and after cultivation. The field experiments concluded that an overall improvement of about 40% in output (ha h(-1)) could be obtained when using the new plow (combination of disk and chisel) compared with a conventional plow. The aggregate analysis of the cultivated layer revealed that the performance of the two machines was largely similar and no significant differences were seen in potato production rates during two years of field experiments, indicating no disadvantage from using an alternative to the moldboard plow. PMID:19090278

  13. A New Model of Teaching Pedagogy in CHISEL for the 21th Century.

    ERIC Educational Resources Information Center

    Huang, Li-yi

    This paper describes and compares six models for teaching second languages developed and adopted since 1840 (grammar-translation, direct, structural, situational, audiolingual, and communicative methods), and proposes a seventh, the cognitive-linguistic method, incorporating Noam Chomsky's theory of learning. The model takes both extralinguistic…

  14. Watermelon transplanted by chisel, strip-tillage, and bedding methods produce similar yield and quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon plants grown in semi-arid, subtropical south Texas (Lat. 26° N) are subject to wind and high solar loads. In an effort to provide an environment that would reduce wind-related sand blasting, early transplant desiccation, and vine damage and reduced soil temperatures, watermelon seedlings...

  15. Shoot, shovel and shut up: cryptic poaching slows restoration of a large carnivore in Europe

    PubMed Central

    Liberg, Olof; Chapron, Guillaume; Wabakken, Petter; Pedersen, Hans Christian; Hobbs, N. Thompson; Sand, Håkan

    2012-01-01

    Poaching is a widespread and well-appreciated problem for the conservation of many threatened species. Because poaching is illegal, there is strong incentive for poachers to conceal their activities, and consequently, little data on the effects of poaching on population dynamics are available. Quantifying poaching mortality should be a required knowledge when developing conservation plans for endangered species but is hampered by methodological challenges. We show that rigorous estimates of the effects of poaching relative to other sources of mortality can be obtained with a hierarchical state–space model combined with multiple sources of data. Using the Scandinavian wolf (Canis lupus) population as an illustrative example, we show that poaching accounted for approximately half of total mortality and more than two-thirds of total poaching remained undetected by conventional methods, a source of mortality we term as ‘cryptic poaching’. Our simulations suggest that without poaching during the past decade, the population would have been almost four times as large in 2009. Such a severe impact of poaching on population recovery may be widespread among large carnivores. We believe that conservation strategies for large carnivores considering only observed data may not be adequate and should be revised by including and quantifying cryptic poaching. PMID:21849323

  16. Shoot, shovel and shut up: cryptic poaching slows restoration of a large carnivore in Europe.

    PubMed

    Liberg, Olof; Chapron, Guillaume; Wabakken, Petter; Pedersen, Hans Christian; Hobbs, N Thompson; Sand, Håkan

    2012-03-01

    Poaching is a widespread and well-appreciated problem for the conservation of many threatened species. Because poaching is illegal, there is strong incentive for poachers to conceal their activities, and consequently, little data on the effects of poaching on population dynamics are available. Quantifying poaching mortality should be a required knowledge when developing conservation plans for endangered species but is hampered by methodological challenges. We show that rigorous estimates of the effects of poaching relative to other sources of mortality can be obtained with a hierarchical state-space model combined with multiple sources of data. Using the Scandinavian wolf (Canis lupus) population as an illustrative example, we show that poaching accounted for approximately half of total mortality and more than two-thirds of total poaching remained undetected by conventional methods, a source of mortality we term as 'cryptic poaching'. Our simulations suggest that without poaching during the past decade, the population would have been almost four times as large in 2009. Such a severe impact of poaching on population recovery may be widespread among large carnivores. We believe that conservation strategies for large carnivores considering only observed data may not be adequate and should be revised by including and quantifying cryptic poaching. PMID:21849323

  17. "Shovel-Ready" Data: The Stimulus Package and State Longitudinal Data Systems

    ERIC Educational Resources Information Center

    Ewell, Peter T.

    2009-01-01

    The American Reinvestment and Recovery Act, commonly referred to simply as "the stimulus package," is poised to pump over $100 billion into U.S. public education in the next few years. This allocation reflects the Obama administration's new commitment to education as a public good, which is embodied in President Obama's ambitious goal of 60…

  18. Simulation of Stress-Strain State of Shovel Rotary Support Kingpin

    NASA Astrophysics Data System (ADS)

    Khoreshok, A. A.; Buyankin, P. V.; Vorobiev, A. V.; Dronov, A. A.

    2016-04-01

    The article presents the sequence of computational simulation of stress-strain state of shovel’s rotary support. Computation results are analyzed, the kingpin is specified as the most loaded element, maximum stress zones are identified. Kingpin design modification such as enhancement of fillet curvature radius to 25 mm and displacement of eyebolt holes on the diameter of 165 mm are proposed, thus diminishing impact of stress concentrators and improving reliability of the rotary support.

  19. Cyber Shovels in High School: An Online Soil Science Resource for Educators

    NASA Astrophysics Data System (ADS)

    Krzic, M.; Basiliko, N.; Bedard-Haughn, A.; Humphreys, E.; Price, G.; Dampier, L.; Grand, S.; Dynatkar, S.; Crowley, C.

    2012-04-01

    Declining enrolment in soil science courses at post-secondary institutions in Canada and around the world tells us that fewer high school students are considering a career in this discipline than ever before. This may be due to soil science programs losing visibility as they are incorporated into other, larger programs; a lack of awareness of what opportunities exist for soil science professionals; or a disinclination of high school educators to use soil science scenarios as examples in their science curriculum. In 2010, we initiated a three-year, multi-institutional project aimed at introducing soil science concepts into high school curricula across Canada. The goals of this project are to promote learning about the importance of soil as a natural resource, provide useful tools that high school educators can incorporate into their lesson plans, and encourage students to pursue soil science in their higher education. The tool (http://soilweb.landfood.ubc.ca/youth/) features five main themes: (1) descriptions of soil research projects currently undertaken by faculty at five universities across Canada; (2) links to age-appropriate soil related resources that provide exercises and examples teachers can easily use; (3) profiles of soil scientists "at work" in a diverse range of careers to motivate future soil scientists; (4) examples of recent news stories about soil to highlight its relevance in our day to day lives; and (5) a soil forum for students and teachers to ask questions. This tool will be further refined by incorporating feedback obtained from high school teachers and students.

  20. Teach Students to Dig for Understanding Using an Unexpected Technological Shovel

    ERIC Educational Resources Information Center

    Lake, Susan E. L.

    2004-01-01

    Online genealogy tools is an unexpected resource as these tools not only serve valuable for genealogy research, but also can be used by students to learn about their country's past and learn to use primary materials to draw conclusions. Some of these Online sources like the 1880 census available at www.ancestry.com, www.thepastwhispers.com, which…

  1. It's still true: plowing up alfalfa releases plenty of N for corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers and their advisors question the accuracy of published fertilizer N replacement values that alfalfa provides to first-year corn. Their skepticism has risen as corn yields have increased, but higher fertilizer prices have heightened the need to trim unproductive inputs. Recent Minnesota data c...

  2. Nitrogen and phosphorus concentrations of runoff as affected by moldboard plowing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The repeated excessive application of manure on cropland areas can cause nutrients to accumulate near the soil surface and increase nutrient transport by overland flow. Inverting soils with high surface nutrient content could reduce runoff nutrient transport. This study was conducted to measure the ...

  3. The stork, the plow, rural social structure and tropical deforestation in poor countries?

    PubMed

    Rock, M T

    1996-01-01

    This study is an exploration of the relationships between income, demographic pressure, technological change in agriculture, and the structure of political economies in light of cross-country differences in deforestation. The study focuses on small farmers and shifting cultivation. The analysis is based on a model developed by Larson (1994) that accounts for rural poverty, rootlessness, and distribution of landholdings. Regression equations model the average annual rate of deforestation, the relative area under forests, and a recursive model that includes both the deforestation rate and the forested area. Deforestation was reasonably well explained by a dummy variable for Asia, a rank order variable of the amount of forested area in 1980, the gross domestic product per capita in 1990, the average annual population growth rate during 1981-90, and the percentage increase in value added to agriculture during 1981-90 in 1990 dollars. Findings indicate that a 10% increase in the population growth rate increased the rate of deforestation by 10.6%. A 10% increase in income per capita increased deforestation by 49.5%. The influence of income on deforestation followed Kuznet's U-shaped curve. The turning point for reduced deforestation was income of $3500 per capita. Only Central and South America are near this income level. An increase in 1 agricultural worker per household increased deforestation by 50%. A 10% increase in smallholders' share of agricultural land reduced deforestation by 3.4%. Countries with high rural rootlessness had 23.6% less relative area under forests, suggesting that rural rootlessness rather than poverty per se leads to deforestation. The recursive model shows that demographic pressures led to deforestation and were mediated by technological change. Political economy theories of deforestation received strong empirical support. PMID:12292273

  4. Influence of plow pan on the enrichment and depletion of heavy metals in the surface soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydropedology is a new discipline that uses pedological information to understand the soil water movement, and thus the storage, transformation, and transportation of heavy metals (HMs). However, limited studies have investigated how the hydropedological feature, for example the water-restrictive so...

  5. A Skunk Is in the Sky (or Is It a Plow?).

    ERIC Educational Resources Information Center

    Lebofsky, Nancy R.

    1994-01-01

    Describes Project ARTIST (Astronomy-Related Teacher Inservice Training). Using hands-on science experiences, an integrated curriculum, and translated materials, teachers can make space science accessible and interesting to elementary and middle school children. (ZWH)

  6. Force and flow at the onset of drag in plowed granular media.

    PubMed

    Gravish, Nick; Umbanhowar, Paul B; Goldman, Daniel I

    2014-04-01

    We study the transient drag force FD on a localized intruder in a granular medium composed of spherical glass particles. A flat plate is translated horizontally from rest through the granular medium to observe how FD varies as a function of the medium's initial volume fraction, ϕ. The force response of the granular material differs above and below the granular critical state, ϕc, the volume fraction which corresponds to the onset of grain dilatancy. For ϕ<ϕc FD increases monotonically with displacement and is independent of drag velocity for the range of velocities examined (<10 cm/s). For ϕ>ϕc, FD rapidly rises to a maximum and then decreases over further displacement. The maximum force for ϕ>ϕc increases with increasing drag velocity. In quasi-two-dimensional drag experiments, we use granular particle image velocimetry (PIV) to measure time resolved strain fields associated with the horizontal motion of a plate started from rest. PIV experiments show that the maxima in FD for ϕ>ϕc are associated with maxima in the spatially averaged shear strain field. For ϕ>ϕc the shear strain occurs in a narrow region in front of the plate, a shear band. For ϕ<ϕc the shear strain is not localized, the shear band fluctuates in space and time, and the average shear increases monotonically with displacement. Laser speckle measurements made at the granular surface ahead of the plate reveal that for ϕ<ϕc particles are in motion far from the intruder and shearing region. For ϕ>ϕc, surface particles move only during the formation of the shear band, coincident with the maxima in FD, after which the particles remain immobile until the sheared region reaches the measurement region. PMID:24827236

  7. Determination of methyl bromide in air resulting from pre-plant fumigations of plowed fields

    SciTech Connect

    Woodrow, J.E.; Honaganahalli, P.; Seiber, J.N.

    1995-12-31

    A method for measuring residues of methyl bromide in air entails concentrating the fumigant on charcoal from an airstream at a flowrate of 100 ml/min, desorption of the trapped material with benzyl alcohol solvent in a sealed vial at 60-110{degrees}C for 10-15 min, and then sampling of the equilibrated vapor for gas chromatographic assay using electron-capture detection. The desorbed vapor is chromatographed on a 27 in x 0.32 mm (id) porous-layer open tubular column, on which methyl bromide has a retention time of about 6 min at 90{degrees}C and at a carrier gas flowrate of 3-3.5 ml/min. Using this method, standard curves were linear over at least three orders of magnitude and a practical limit of detection for field air was about 20 ng/m{sup 3} ({approximately}5 ppt). This method has been used in studies concerned with methyl bromide volatilization from fumigated fields and with ambient background levels.

  8. Diverse No-Till Irrigated Cropping Systems Instead of Burning and Plowing Continuous Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field burning of stubble has long been used as a management tool for irrigated wheat in the Inland Pacific Northwest. Concerns about regional air quality and government regulations led growers and scientists to conduct a 6-year no-till field experiment to evaluate two cycles of a 3-year irrigated c...

  9. Force and flow at the onset of drag in plowed granular media

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Umbanhowar, Paul B.; Goldman, Daniel I.

    2014-04-01

    We study the transient drag force FD on a localized intruder in a granular medium composed of spherical glass particles. A flat plate is translated horizontally from rest through the granular medium to observe how FD varies as a function of the medium's initial volume fraction, ϕ. The force response of the granular material differs above and below the granular critical state, ϕc, the volume fraction which corresponds to the onset of grain dilatancy. For ϕ <ϕc FD increases monotonically with displacement and is independent of drag velocity for the range of velocities examined (<10 cm/s). For ϕ >ϕc, FD rapidly rises to a maximum and then decreases over further displacement. The maximum force for ϕ >ϕc increases with increasing drag velocity. In quasi-two-dimensional drag experiments, we use granular particle image velocimetry (PIV) to measure time resolved strain fields associated with the horizontal motion of a plate started from rest. PIV experiments show that the maxima in FD for ϕ >ϕc are associated with maxima in the spatially averaged shear strain field. For ϕ >ϕc the shear strain occurs in a narrow region in front of the plate, a shear band. For ϕ <ϕc the shear strain is not localized, the shear band fluctuates in space and time, and the average shear increases monotonically with displacement. Laser speckle measurements made at the granular surface ahead of the plate reveal that for ϕ <ϕc particles are in motion far from the intruder and shearing region. For ϕ >ϕc, surface particles move only during the formation of the shear band, coincident with the maxima in FD, after which the particles remain immobile until the sheared region reaches the measurement region.

  10. X-ray computed microtomography analysis of the influence of different agricultural treatments on the topsoil porosity of a Grey Brown Luvisol from Ontario

    NASA Astrophysics Data System (ADS)

    Taina, I. A.; Heck, R. J.; Scaiff, N. T.

    2009-05-01

    One of the most important applications of X-ray computed tomography (CT) for the study of soil is the characterization of the shape and spatial distribution of pores. Analysis of 3D X-ray CT image data, related to different pore categories, can provide insight to soil structural changes, which have implications in water infiltration and soil aeration, resulting from agricultural practices. The aim of this study was to evaluate changes in the spatial characteristics of voids, due to tillage practices, in the Ap horizon of an Orthic Grey- Brown Luvisol (located at the Elora Research Station of the University of Guelph). Undisturbed oriented soil samples were collected from ten plots representing different tillage treatments: spring moldboard plow, spring moldboard plow, cultivate and pack, fall moldboard plow, cultivate and pack, spring tandem disc, no cultivator, fall offset disc, fall offset disc, cultivate and pack, fall chisel plow, cultivate and pack, zero zone till (soys twin rows), zero tillage (long term), and zero tillage (corn residue removed in row, soys twin rows). Since the utilization of standardized classes, in the quantification of similar features, proved to be necessary in order to obtain comparable results, categories of pores, separated according to their size, circularity and orientation were considered in the interpretation of data. Total volume of pores and volume percentage of each class were calculated, revealing substantial differences among the analyzed soil samples.

  11. Soil mixing to decrease surface stratification of phosphorus in manured soils.

    PubMed

    Sharpley, Andrew N

    2003-01-01

    Continual applications of fertilizer and manure to permanent grassland or no-till soils can lead to an accumulation of P at the surface, which in turn increases the potential for P loss in overland flow. To investigate the feasibility of redistributing surface stratified P within the soil profile by plowing, Mehlich-3 P rich surface soils (128-961 mg kg(-) in 0-5 cm) were incubated with lower-P subsoil (16-119 mg kg(-1) in 5-20 cm) for 18 manured soils from Oklahoma and Pennsylvania that had received long-term manure applications (60-150 kg P ha(-1) yr(-1) as dairy, poultry, or swine manure for up to 20 yr). After incubating a mixture of 5 g surface soil (0- to 5-cm depth) and 15 g subsoil (5- to 20-cm depth) for 28 d, Mehlich-3 P decreased 66 to 90% as a function of the weighted mean Mehlich-3 P of surface and subsoil (i.e.. 1:3 ratio) (r2 = 0.87). At Klingerstown, Northumberland County, south central Pennsylvania, a P-stratified Berks soil (Typic Dystrochrept) (495 mg kg(-1) Mehlich-3 P in 0- to 5-cm depth) was chisel plowed to about 25 cm and orchardgrass (Dactylis glomerata L.) planted. Once grass was established and erosion minimized (about 20 wk after plowing and planting), total P concentration in overland flow during a 30-min rainfall (6.5 cm h(-1)) was 1.79 mg L(-1) compared with 3.4 mg L(-1) before plowing, with dissolved P reduced from 2.9 to 0.3 mg L(-1). Plowing P-stratified soils has the potential to decrease P loss in overland flow, as long as plowing-induced erosion is minimized. PMID:12931893

  12. Evaluation of surgically assisted rapid maxillary expansion with piezosurgery versus oscillating saw and chisel osteotomy - a randomized prospective trial

    PubMed Central

    2013-01-01

    Background Ultrasonic bone-cutting surgery has been introduced as a feasible alternative to the conventional sharp instruments used in craniomaxillofacial surgery because of its precision and safety. The piezosurgery medical device allows the efficient cutting of mineralized tissues with minimal trauma to soft tissues. Piezoelectric osteotome has found its role in surgically assisted rapid maxillary expansion (SARME), a procedure well established to correct transverse maxillary discrepancies. The advantages include minimal risk to critical anatomic structures. The purpose of this clinical comparative study (CIS 2007-237-M) was to present the advantages of the piezoelectric cut as a minimally invasive device in surgically assisted, rapid maxillary expansion by protecting the maxillary sinus mucosal lining. Methods Thirty patients (18 females and 12 males) at the age of 18 to 54 underwent a surgically assisted palatal expansion of the maxilla with a combined orthodontic and surgical approach. The patients were randomly divided into two separate treatment groups. While Group 1 received conventional surgery using an oscillating saw, Group 2 was treated with piezosurgery. The following parameters were examined: blood pressure, blood values, required medication, bleeding level in the maxillary sinus, duration of inpatient stay, duration of surgery and height of body temperature. Results The results displayed no statistically significant differences between the two groups regarding laboratory blood values and inpatient stay. The duration of surgery revealed a significant discrepancy. Deploying piezosurgery took the surgeon an average of 10 minutes longer than working with a conventional-saw technique. However, the observation of the bleeding level in the paranasal sinus presented a major and statistically significant advantage of piezosurgery: on average the bleeding level was one category above the one of the remaining patients. Conclusion This method of piezoelectric surgery with all its advantages is going to replace many conventional operating procedures in oral and maxillofacial surgery. Trial registration CIS 2007-237-M PMID:23414112

  13. FINITE VOLUME ELEMENT APPROXIMATIONS OF NONLOCAL IN TIME ONE-DIMENSIONAL PLOWS IN POROUS MEDIA. (R825207)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. [Testing and commercialization of a cotton stalk shredder and plow]. Technical progress report, October--December 1995

    SciTech Connect

    Thacker, G.W.

    1996-01-27

    This quarterly report describes work on Task 1: Field test and sell prototype to Ellis Equipment, Ltd; Task 2: Design, build, and field test two prototypes; and Task 3: Produce and sell Pegasus to farmers. The equipment has been built to shred stalks, deeply till the soil, and prepare seedbeds for cotton plants. The equipment has been field tested in Australia and is currently being field tested in California and Arizona. Unexpected problems appeared with hard dry soils and this report describes improvements made.

  15. Modeling organic carbon dynamics under no-tillage and plowed systems in tropical soils of Brazil using CQESTR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    CQESTR simulates the effect of several management practices on soil organic carbon stocks. The model had been calibrated and validated in temperate regions. Our objective was to calibrate the CQESTR model and evaluate its performance for simulating carbon dynamics as affected by tillage practices in...

  16. Evolution of the plow over 10,000 years and the rationale for no-till farming

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture originated 10 to 13 millennia ago in the Fertile Crescent of the Near East, mostly along the Tigris, Euphrates, Nile, Indus and Yangtze River valleys and was introduced into Greece and southeast Europe > 8000 years ago. Sumerian and other civilizations developed a wide variety of simple ...

  17. Quantification of Soil Physical Properties by Using X-Ray Computerized Tomography (CT) and Standard Laboratory (STD) Methods

    SciTech Connect

    Maria Ambert Sanchez

    2003-12-12

    The implementation of x-ray computerized tomography (CT) on agricultural soils has been used in this research to quantify soil physical properties to be compared with standard laboratory (STD) methods. The overall research objective was to more accurately quantify soil physical properties for long-term management systems. Two field studies were conducted at Iowa State University's Northeast Research and Demonstration Farm near Nashua, IA using two different soil management strategies. The first field study was conducted in 1999 using continuous corn crop rotation for soil under chisel plow with no-till treatments. The second study was conducted in 2001 and on soybean crop rotation for the same soil but under chisel plow and no-till practices with wheel track and no-wheel track compaction treatments induced by a tractor-manure wagon. In addition, saturated hydraulic (K{sub s}) conductivity and the convection-dispersion (CDE) model were also applied using long-term soil management systems only during 2001. The results obtained for the 1999 field study revealed no significant differences between treatments and laboratory methods, but significant differences were found at deeper depths of the soil column for tillage treatments. The results for standard laboratory procedure versus CT method showed significant differences at deeper depths for the chisel plow treatment and at the second lower depth for no-till treatment for both laboratory methods. The macroporosity distribution experiment showed significant differences at the two lower depths between tillage practices. Bulk density and percent porosity had significant differences at the two lower depths of the soil column. The results obtained for the 2001 field study showed no significant differences between tillage practices and compaction practices for both laboratory methods, but significant differences between tillage practices with wheel track and no-wheel compaction treatments were found along the soil profile for

  18. Dissolved organic C and N pools in soils amended with composted and thermally-dried sludge as affected by soil tillage systems and sampling depth

    NASA Astrophysics Data System (ADS)

    García-Gil, Juan Carlos; Soler-Rovira, Pedro Angel; García López de Sa, Esther; Polo, Alfredo

    2013-04-01

    Soil tillage practices exert a significant influence on the dynamic of soluble organic C and N pools, affecting nutrient cycling in agricultural systems by enhancing its mineralization through microbial activities or stabilization in soil microaggregates, which contribute to mitigate greenhouse gases emissions. The objective of the present research was to determine the influence of three different soil management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) obtained from wastewater treatment processes on dissolved organic C (water-soluble organic C -WSOC-, carbohydrates, phenolic compounds) and soluble N (total-N, NH4+, NO3-) pools in a long-term field experiment (27 years) conducted on a sandy-loam soil at the experimental station "La Higueruela" (40° 03'N, 4° 24'W) under semi-arid conditions. Both organic amendments were applied at a rate of 30 tonnes per hectare prior to tillage practices. Unamended soils were used as control for each tillage system. Soil sampling was performed two months after tillage practices at the following depths for each treatment: 0-10 cm, 10-20 cm and 20-30 cm. Results obtained for unamended soils showed that no-tillage management increased total-N, NH4+ and NO3- contents at the 0-10 cm depth samples, meanwhile WSC and carbohydrates contents were larger at 20-30 cm depth samples in both moldboard and no-tillage plots. CS and TSS-amended soils presented a general increase in soluble C and N compounds, being significantly higher in TSS-amended soils, as TSS contains a great amount of labile organic C and N substrates due to the lack of stabilization treatment. TSS-amended soils under no-tillage and chisel plowing showed larger N, NH4+ and NO3- content at the 0-10 cm samples, meanwhile moldboard management exhibited larger NH4+ and NO3- content at 10-20 and 20-30 cm samples, possibly due to the incorporation of TSS at deeper depths (20-40 cm). CS

  19. Dinosaur Tracks, Erosion Marks and Midnight Chisel Work (But No Human Footprints) in the Cretaceous Limestone of the Paluxy River Bed, Texas.

    ERIC Educational Resources Information Center

    Milne, David H.; Schafersman, Steven D.

    1983-01-01

    Creationists claim that human footprints coexist with those of dinosaurs in Cretaceous limestone exposed in the Paluxy riverbed near Glen Rose, Texas. Analysis of photos shows that the features in question are not human footprints and that creationist documentation/analysis of the prints is riddled with omissions, misrepresentations,…

  20. Soil physical quality changes under different management systems after 10 years in Argentinian Humid Pampa

    NASA Astrophysics Data System (ADS)

    Costa, J. L.; Aparicio, V. C.; Cerda, A.

    2014-08-01

    The Argentinian Humid Pampa extends over about 60 million ha, 90% of which are agricultural lands. The southeast of the Buenos Aires Province is part of the Humid Pampa (1 206 162 ha). The main crops are wheat, sunflower, corn and soybean. The management systems used in the area are: moldboard plow (MP), chisel plow (CP) and no-till (NT). Excessive soil cultivation under MP causes decreases in the soil organic carbon content (SOC). Adopting NT may reduce the effects of intensive agriculture, through the maintenance and accumulation of SOC. However, the soil compaction under NT causes degradation of the soil structure, reduces the soil water availability and reduces the soil hydraulic conductivity. We evaluated the evolution of the soil physical parameters in three management systems. After 10 years of experiments in four farmers' fields, we found that: soil bulk density was significantly higher under NT. The change in mean weight diameter (CMWD) of aggregates increased as the management system became more intensive. We did not find significant differences in time and management systems in hydraulic conductivity at tension (h)0 cm and h=20 cm. The reduction in total porosity under NT is mainly a product of a reduction in the percentage of mesopores in the soil. Time had no statistically significant effect on the SOC content. The management system did not affect the yields of crop. In this work, the results indicate a modification of some soil physical parameters (porosity, near-saturated hydraulic conductivity, soil structure) due to uninterrupted agricultural production.

  1. Civic Learning through Agricultural Improvement: Bringing the Loom and the Anvil into Proximity with the Plow. Studies in the History of Education

    ERIC Educational Resources Information Center

    Lauzon, Glenn P.

    2010-01-01

    How do people use education to respond to change? How do people learn what is expected of "good citizens" in their communities? These questions have long concerned educational historians, civic educators, and social scientists. In recent years, they have captured national attention through high-profile education reform proposals and civic…

  2. Salmonella and fecal indicator bacteria in tile waters draining poultry litter application fields in central Iowa

    NASA Astrophysics Data System (ADS)

    Hruby, C.; Soupir, M.

    2012-12-01

    E. coli and enterococci are commonly used as pathogen indicators in surface waters. Along with these indicators, pathogenic Salmonella are prevalent in poultry litter, and have the potential to be transported from land-application areas to tile waters and ultimately to impact waters that are used for drinking-water and recreation. The fate and transport of these bacteria to drainage tiles from application fields, and the correlation of fecal indicator bacteria to pathogens in this setting, is poorly understood. In this field study, samples were obtained from poultry litter, soil, and drainage tile waters below chisel-plowed and no-till cornfields in central Iowa where poultry litter was applied each year in late spring prior to planting. Litter was applied at three different rates; commercial fertilizer with no litter, a low application rate based on the nitrogen requirements of the corn (PL1), and double the low rate (PL2). This site is characterized by low sloping (0-9%) Clarion and Nicollet soils, which are derived from glacial till. Samples were collected from April to September for three years (2010-12) when tiles were flowing. Record high precipitation fell during the sampling period in 2010, while 2011 and 2012 were exceptionally dry years at this location. Grab samples were taken directly from flowing tiles after every rainfall event (>2 cm in less than 24 hours) and samples were collected hourly throughout selected events using an automatic sampling device. Concentrations of E. coli, enterococci and Salmonella spp. were quantified by membrane filtration and growth on selective agars. Peak bacteria concentrations following rainfall events were often one order of magnitude higher in tile waters discharging from no-till plots, despite the smaller size and lower tile flow rates at these plots compared to the chisel-plowed plots. Bacteria concentrations regularly varied by two orders of magnitude in response to rainfall events. Bacteria transport via macropores

  3. Strength Properties and Organic Carbon of Soils in the North Apalachian Region

    SciTech Connect

    Blanco-Canqui, H; Lal, Rattan; Owen, L B.; Post, W M.; Izaurralde, R Cesar C.

    2005-04-01

    Soil strength influenced by management and soil properties controls plant growth, root development, and soil-moisture relations. The impact of textural and structural parameters on soil strength is moderated by soil organic C (SOC) concentration. Therefore, the objectives of this study were to assess differences in soil strength and SOC concentration in watersheds under long-term (>15 yr) management practices in the North Appalachian region on a predominantly Typic Hapludults on undulating slopes (>6% slope). Seven watersheds without field replication under moldboard plow (MP), chisel plow, disk with beef cattle manure (DiskM), no-till with beef cattle manure (NTm), no-till with no beef cattle manure (NTnm), pasture, and forest were studied. Cone index (CI), shear strength, bulk density (b), volumetric moisture content (v), and SOC concentration were determined at the summit, backslope, and footslope landscape positions at the 0- to 10-, 10- to 20-, and 20- to 30-cm depths. The SOC concentration was slightly higher at the footslope than at the summit position in the cultivated watersheds. The b was lower at the footslope than at the summit in NTm (1.22 vs. 1.42 Mg m{sup -3}) and chisel (1.34 vs. 1.47 Mg m{sup -3}) treatments. Forest had the lowest CI (0.19 MPa), shear strength (6.11 kPa), and b (0.93 Mg m{sup -3}) and the highest SOC concentration (62.7 g kg{sup -1}), whereas MP had the highest CI (0.67 MPa), shear strength (25.5 kPa), b (1.44 Mg m{sup -3}), and the lowest SOC concentration (13.6 g kg{sup -1}) in the 0- to 10-cm depth (P < 0.01). The SOC concentration in NTm was 1.7 times higher than that in NTnm, and both no-till treatments had lower b (<1.21 Mg m{sup -3}) than MP (1.44 Mg m{sup -3}) at 0- to 10-cm depth (P < 0.01). Manuring decreased both CI and shear strength, but increased SOC concentration. The b, v, and SOC concentration were potential predictors of CI; whereas b and SOC concentration were of shear strength (r2 > 0.42; P < 0.01). Results show

  4. Soil Carbon Changes in Transitional Grain Crop Production Systems in South Dakota

    NASA Astrophysics Data System (ADS)

    Woodard, H. J.

    2004-12-01

    Corn-C (Zea Mays L.), soybean-S (Glycine max L.) and spring wheat-W (Triticum aestivum L.) crops were seeded as a component of either a C-S, S-W, or C-S-W crop rotation on silt-loam textured soils ranging from 3.0-5.0% organic matter. Conservation tillage(chisel plow-field cultivator) was applied to half of the plots. The other plots were direct seeded as a no-till (zero-tillage) treatment. Grain yield and surface crop residues were weighed from each treatment plot. Crop residue (stover and straw) was removed from half of the plots. After four years, soil samples were removed at various increments of depth and soil organic carbon (C) and nitrogen (N) was measured. The ranking of crop residue weights occurred by the order corn>>soybean>wheat. Surface residue accumulation was also greatest with residue treatments that were returned to the plots, those rotations in which maize was a component, and those without tillage. Mean soil organic carbon levels in the 0-7.5cm depth decreased from 3.41% to 3.19% (- 0.22%) with conventional tillage (chisel plow/field cultivator) as compared to a decrease from 3.19% to 3.05% (-0.14%) in plots without tillage over a four year period. Organic carbon in the 0-7.5cm depth decreased from 3.21% to 3.01% (- 0.20%) after residue removed as compared to a decrease from 3.39% to 3.23% (-0.17%) in plots without tillage applied after four years. The soil C:N ratio (0-7.5cm) decreased from 10.63 to 10.37 (-0.26 (unitless)) in the tilled plots over a four-year period. Soil C:N ratio at the 0-7.5cm depth decreased from 10.72 to 10.04 (-0.68) in the no-till plots over a four year period. Differences in the soil C:N ratio comparing residue removed and residue returned were similar (-0.51 vs. -0.43 respectively). These soils are highly buffered for organic carbon changes. Many cropping cycles are required to determine how soil carbon storage is significantly impacted by production systems.

  5. Edaphic and crop production changes resulting from pipeline installation in semiarid agricultural ecosystems

    SciTech Connect

    Zellmer, S.D.; Taylor, J.D.; Carter, R.P.

    1985-01-01

    The effects of pipeline installation on soil properties and crop production are being documented on three transects (pipe ditch, working side, and control) at four sites (dryland row crop, native pasture, dryland wheat, and irrigated cropland) in Beaver County, Oklahoma. Plant-cover data from the native pasture site show a 37% increase in cover on the pipe ditch during the initial growth season; no significant differences in cover were observed when the control and working side transects were compared. Wheat yield on the pipe ditch at the irrigated crop site was significantly higher, a fact attributed to increased moisture-retention capacity and lower bulk density of the pipe ditch soil. The significantly higher grain sorghum yield on the right-of-way at the dryland row crop site may have resulted from the reclamation practice of chisel plowing the right-of-way on croplands following pipeline construction. Data from the initial sampling and first year of monitoring of the Beaver County sites indicate pipeline installations in semiarid agro-ecosystems have either positive or negligible impacts on soil properties and crop production. 22 refs., 1 fig., 3 tabs.

  6. Effects of changes in land use on soil physical properties and soil organic carbon content in a wheat-corn-sunflower crop sequence, in a loam soil of Argentina.

    NASA Astrophysics Data System (ADS)

    Aparicio, V.; Costa, J. L.

    2012-04-01

    The Argentinean Humid Pampas extend over about 60 million hectares, 90% of which are agricultural lands. The Southeast of the Buenos Aires Province is part of the Humid Pampas, it covers over 1,206,162 hectares, the mean annual temperature is 13.3 °C and the climate is sub-humid. At the present only 6% of the lands are used for pasture. The main activities are agriculture and cattle production. The main crops are wheat, sunflower, corn and soybean. The tillage systems used in the area are: moldboard plow (MP), chisel plow (CP) and no-till (NT). Excessive soil cultivation under MP generates decreases in the levels of soil organic carbon (SOC). The magnitude of such decrease depends on the intensity of the tillage system, the tillage timeliness and the amount and quality of the residues. Adopting NT may reduce the effects of intensive agriculture, through the maintenance and accumulation of SOC. However, there are evidences that, under NT, the bulk density (ρb) in the superficial layers of the soil increases. The soil compaction causes degradation of the soil structure, reduces the soil water availability and reduces the soil hydraulic conductivity. With this scenario and the tendency to increase the surface under NT in the Southeast Humid Pampas, we evaluated the evolution of some soil physical properties and the SOC in a 10-year experiment with a wheat-corn-sunflower rotation. The experiment was carried out in four localities at farmerś fields under three different tillage systems: MP, CP and NT in a randomized complete block design, considering each locality as a block. Each plot had 50 m in width by 100 m length and the treatments were: NT, MP and CP. The results of this experiment have allowed us to verify that: i) the wheat-corn-sunflower crop sequence showed a tendency to reduce the values of bulk density (ρb) but NT increased ρb in the superficial soil layers; ii) the more intensive the tillage system, the higher the change in the mean weight diameter

  7. Effect of Conversion from Natural Grassland to Arable Land on Soil Carbon Reserve in the Argentinean Rolling Pampas

    NASA Astrophysics Data System (ADS)

    Andriulo, A. E.; Irizar, A. B.; Mary, B.; Wilson, M. G.

    2012-04-01

    The evaluation of the effect of land use change on accumulation of soil organic carbon (SOC) requires reliable data obtained from georeferenced sites with land use history records. The purpose of this study was to evaluate long term changes in the reserves of SOC in a typical Argiudol of the Pergamino series after the introduction of agriculture. Measures of soil organic carbon concentration and bulk density of Ap and A12 horizons were carried out in three sites of the Pergamino County (N of Buenos Aires province): a reference field with untilled pristine soil (33° 57' S; 60° 34' W), a field with 31 years (1980-2011) of agriculture (31Y) located next to the former, and a third field (33° 46' S; 60° 37' W) with 80 years (1910/1990) of agriculture (80Y). 31Y has been under continuous soybean cultivation with conventional tillage (CT) that consists of moldboard plow or double disk harrowing. At 80K the cultivation sequence was: 44 years of corn + 9 years of flax + 2 years of wheat + 17 years of wheat/soybean double cropping + 1 year of lentil; mostly under CT, some years under chisel plow during the 70's and a few years under zero tillage in soybean after wheat sown with conventional tillage during the 80's. Before the introduction of mechanical harvesting (1947) crop residues were burnt as well as the wheat stubble during the conventional double cropping period (1970-1980). Soil texture (23±1% clay, with predominance of illite) and field slopes (<0.5%) were similar in the three sites. Nitrogen and phosphorus fertilization rates were minimal due to the low crop response. The results are expressed in Mg ha-1 for an A soil horizon mass of 2500 Mg ha-1. The introduction of agriculture decreased SOC stock: 31Y varied from 68.3 to 40.1 Mg ha-1 (41.3% loss) and 80Y from 68.3 to 47.2 Mg ha-1 (30% loss). The SOC loss was the result of the mineralization of a large amount labile SOC present in the pristine soil and low annual additions of carbon issued from crop residue

  8. Comparative losses of glyphosate and selected residual herbicides in surface runoff from conservation-tilled watersheds planted with corn or soybean.

    PubMed

    Shipitalo, Martin J; Owens, Lloyd B

    2011-01-01

    Residual herbicides regularly used in conjunction with conservation tillage to produce corn ( L.) and soybean [ (L.) Merr] are often detected in surface water at concentrations that exceed their U.S. maximum contaminant levels (MCL) and ecological standards. These risks might be reduced by planting glyphosate-tolerant varieties of these crops and totally or partially replacing the residual herbicides alachlor, atrazine, linuron, and metribuzin with glyphosate, a contact herbicide that has a short half-life and is strongly sorbed to soil. Therefore, we applied both herbicide types at typical rates and times to two chisel-plowed and two no-till watersheds in a 2-yr corn/soybean rotation and at half rates to three disked watersheds in a 3-yr corn/soybean/wheat-red clover ( L.- L.) rotation and monitored herbicide losses in surface runoff for three crop years. Average dissolved glyphosate loss for all tillage practices, as a percentage of the amount applied, was significantly less ( ≤ 0.05) than the losses of atrazine (21.4x), alachlor (3.5x), and linuron (8.7x) in corn-crop years. Annual, flow-weighted, concentration of atrazine was as high as 41.3 μg L, much greater than its 3 μg L MCL. Likewise, annual, flow-weighted alachlor concentration (MCL = 2 μg L) was as high as 11.2 and 4.9 μg L in corn- and soybean-crop years, respectively. In only one runoff event during the 18 watershed-years it was applied did glyphosate concentration exceed its 700 μg L MCL and the highest, annual, flow-weighted concentration was 3.9 μg L. Planting glyphosate-tolerant corn and soybean and using glyphosate in lieu of some residual herbicides should reduce the impact of the production of these crops on surface water quality. PMID:21712598

  9. Comparison of Surface Water Quality and Yields from Organically and Conventionally Produced Sweet Corn Plots with Conservation and Conventional Tillage.

    PubMed

    Edgell, Joshua; Osmond, D L; Line, D E; Hoyt, G D; Grossman, J M; Larsen, E M

    2015-11-01

    Organic agricultural systems are often assumed to be more sustainable than conventional farming, yet there has been little work comparing surface water quality from organic and conventional production, especially under the same cropping sequence. Our objective was to compare nutrient and sediment losses, as well as sweet corn ( L. var. ) yield, from organic and conventional production with conventional and conservation tillage. The experiment was located in the Appalachian Mountains of North Carolina. Four treatments, replicated four times, had been in place for over 18 yr and consisted of conventional tillage (chisel plow and disk) with conventional production (CT/Conven), conservation no-till with conventional production (NT/Conven), conventional tillage with organic production (CT/Org), and conservation no-till with organic production (NT/Org). Water quality (surface flow volume; nitrogen, phosphorus, and sediment concentrations) and sweet corn yield data were collected in 2011 and 2012. Sediment and sediment-attached nutrient losses were influenced by tillage and cropping system in 2011, due to higher rainfall, and tillage in 2012. Soluble nutrients were affected by the nutrient source and rate, which are a function of the cropping system. Sweet corn marketable yields were greater in conventional systems due to high weed competition and reduced total nitrogen availability in organic treatments. When comparing treatment efficiency (yield kg ha /nutrient loss kg ha ), the NT/Conven treatment had the greatest sweet corn yield per unit of nutrient and sediment loss. Other treatment ratios were similar to each other; thus, it appears the most sustainably productive treatment was NT/Conven. PMID:26641338

  10. Characterizing phosphorus dynamics in tile-drained agricultural fieldsof eastern Wisconsin

    USGS Publications Warehouse

    Madison, Allison; Ruark, Matthew; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Laura W; Drummy, Nancy; Cooley, Eric

    2014-01-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn–soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66–96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L−1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  11. Characterizing phosphorus dynamics in tile-drained agricultural fields of eastern Wisconsin

    NASA Astrophysics Data System (ADS)

    Madison, Allison M.; Ruark, Matthew D.; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Lara W.; Drummy, Nancy; Cooley, Eric T.

    2014-11-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn-soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66-96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L-1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  12. Fate and transport of tylosin-resistant bacteria and macrolide resistance genes in artificially drained agricultural fields receiving swine manure.

    PubMed

    Luby, Elizabeth M; Moorman, Thomas B; Soupir, Michelle L

    2016-04-15

    Application of manure from swine treated with antibiotics introduces antibiotics and antibiotic resistance genes to soil with the potential for further movement in drainage water, which may contribute to the increase in antibiotic resistance in non-agricultural settings. We compared losses of antibiotic-resistant Enterococcus and macrolide-resistance (erm and msrA) genes in water draining from plots with or without swine manure application under chisel plow and no till conditions. Concentrations of ermB, ermC and ermF were all >10(9)copies g(-1) in manure from tylosin-treated swine, and application of this manure resulted in short-term increases in the abundance of these genes in soil. Abundances of ermB, ermC and ermF in manured soil returned to levels identified in non-manured control plots by the spring following manure application. Tillage practices yielded no significant differences (p>0.10) in enterococci or erm gene concentrations in drainage water and were therefore combined for further analysis. While enterococci and tylosin-resistant enterococci concentrations in drainage water showed no effects of manure application, ermB and ermF concentrations in drainage water from manured plots were significantly higher (p<0.01) than concentrations coming from non-manured plots. ErmB and ermF were detected in 78% and 44%, respectively, of water samples draining from plots receiving manure. Although ermC had the highest concentrations of the three genes in drainage water, there was no effect of manure application on ermC abundance. MsrA was not detected in manure, soil or water. This study is the first to report significant increases in abundance of resistance genes in waters draining from agricultural land due to manure application. PMID:26874610

  13. Transport and persistence of tylosin-resistant enterococci, genes, and tylosin in soil and drainage water from fields receiving Swine manure.

    PubMed

    Garder, Jason L; Moorman, Thomas B; Soupir, Michelle L

    2014-07-01

    Land application of manure from tylosin-treated swine introduces tylosin, tylosin-resistant enterococci, and erythromycin resistant rRNA methylase () genes, which confer resistance to tylosin. This study documents the persistence and transport of tylosin-resistant enterococci, genes, and tylosin in tile-drained chisel plow and no-till agricultural fields treated with liquid swine manure in alternating years. Between 70 and 100% of the enterococci in manure were resistant to tylosin and B concentrations exceeded 10 copies g manure, while the mean F concentrations exceeded 10 copies g manure (T was not detected). The mean concentration of tylosin was 73 ng g manure. Soil collected from the manure injection band closely following application contained >10 copies g soil of both B and F in 2010 and >10 copies g soil after the 2011 application compared to 3 × 10 to 3 × 10 copies g soil in the no-manure control plots. Gene abundances declined over the subsequent 2-yr period to levels similar to those in the no-manure controls. Concentrations of enterococci in tile water were low, while tylosin-resistant enterococci were rarely detected. In approximately 75% of tile water samples, B was detected, and F was detected in 30% of tile water samples, but levels of these genes were not elevated due to manure application, and no difference was found between tillage practices. These results show that tylosin usage increased the short-term occurrence of tylosin-resistant enterococci, genes, and tylosin in soils but had minimal effect on tile drainage water quality in years of average to below average precipitation. PMID:25603096

  14. NOVEL EXCAVATION TECHNOLOGIES FOR EFFICIENT AND ECONOMIC SURFACE MINING

    SciTech Connect

    Vladislav Kecojevic; Samuel Frimpong

    2005-05-01

    Ground excavation constitutes a significant component of production costs in any surface mining operation. The excavation process entails material digging and removal in which the equipment motion is constrained by the workspace geometry. A major excavation problem is the variability of material properties, resulting in varying mechanical energy input and stress loading of shovel dipper-and-tooth assembly across the working bench. This variability has a huge impact on the shovel dipper and tooth assembly in hard formations. With this in mind, the primary objectives of the project were to (i) provide the theoretical basis to develop the Intelligent Shovel Excavation (ISE) technology to solve the problems associated with excavation in material formations; (ii) advance knowledge and frontiers in shovel excavation through intelligent navigation; and (iii) submit proposal for the design, development and implementation of the ISE technology for shovel excavation at experimental surface mining sites. The mathematical methods were used to (i) develop shovel's kinematics and dynamics, and (ii) establish the relationship between shovel parameters and the resistive forces from the material formation during excavation process. The ADAMS simulation environment was used to develop the hydraulic and cable shovel virtual prototypes. Two numerical examples are included to test the theoretical hypotheses and the obtained results are discussed. The area of sensor technology was studied. Application of specific wrist-mounted sensors to characterize the material, bucket and frame assembly was determined. Data acquisition, display and control system for shovel loading technology was adopted. The concept of data acquisition and control system was designed and a shovel boom stresses were simulated. A multi-partner collaboration between research organizations, shovel manufacturer, hardware and sensor technology companies, and surface mining companies is proposed to test design features

  15. Real promise or false hope: DOE's title XVII loan Guarantee

    SciTech Connect

    Massouh, Jennifer F.; Cannon, George D. Jr.; Logan, Suzanne M.; Schwartz, David L.

    2009-05-15

    While the American Recovery and Reinvestment Act of 2009 expanded the DOE loan guarantee program to include certain ''shovel-ready'' projects, and appropriated $6 billion to cover the credit subsidy cost associated with these projects, it failed to resolve some of the most pressing problems facing the program. Here are some recommendations that may finally get some shovels in the ground. (author)

  16. Cold Weather and Cardiovascular Disease

    MedlinePlus

    ... season will bring cooler temperatures and ice and snow for some. For most people, shoveling snow may not lead to any health problems. It’s ... exertion, like lifting a heavy shovel full of snow. Even walking through heavy, wet snow or snow ...

  17. Performance of a Modified Cylinder Cleaner, Part I

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A chisel-shape grid bar with a sharp cutting edge was designed and installed in a modified cylinder cleaner. The cleaner’s seed cotton and lint cleaning performances were evaluated in two tests. Results indicated that a cylinder cleaner with narrowly spaced chisel-shape grid bars connected in seri...

  18. Distribution of organic carbon in physical fractions of soils as affected by agricultural management

    SciTech Connect

    Sindhu, Jagadamma; Lal, Dr. Rattan

    2010-08-01

    Soil organic carbon (SOC) is distributed heterogeneously among different-sized primary particles and aggregates. Further, the SOC associated with different physical fractions respond differently to managements. Therefore, this study was conducted with the objective to quantify the SOC associated with all the three structural levels of SOC (particulate organic matter, soil separates and aggregate-size fractions) as influenced by long-term change in management. The study also aims at reevaluating the concept that the SOC sink capacity of individual size-fractions is limited. Long-term tillage and crop rotation effects on distribution of SOC among fractions were compared with soil from adjacent undisturbed area under native vegetation for the mixed, mesic, Typic Fragiudalf of Wooster, OH. Forty five years of no-till (NT) management resulted in more SOC accumulation in soil surface (0 7.5 cm) than in chisel tillage and plow tillage (PT) treatments. However, PT at this site resulted in a redistribution of SOC from surface to deeper soil layers. The soils under continuous corn accumulated significantly more SOC than those under corn soybean rotation at 7.5 45 cm depth. Although soil texture was dominated by the silt-sized particles, most of the SOC pool was associated with the clay fraction. Compared to PT, the NT treatment resulted in (i) significantly higher proportion of large macroaggregates (>2,000 m) and (ii) 1.5 2.8 times higher SOC concentrations in all aggregate-size classes. A comparative evaluation using radar graphs indicated that among the physical fractions, the SOC associated with sand and silt fractions quickly changed with a land use conversion from native vegetation to agricultural crops. A key finding of this study is the assessment of SOC sink capacity of individual fractions, which revealed that the clay fraction of agricultural soils continues to accumulate more SOC, albeit at a slower rate, with progressive increase in total SOC concentration

  19. Effects of tillage and poultry manure application rates on Salmonella and fecal indicator bacteria concentrations in tiles draining Des Moines Lobe soils.

    PubMed

    Hruby, C E; Soupir, M L; Moorman, T B; Shelley, M; Kanwar, R S

    2016-04-15

    Application of poultry manure (PM) to cropland as fertilizer is a common practice in artificially drained regions of the Upper Midwest United States. Tile-waters have the potential to contribute pathogenic bacteria to downstream waters. This 3-year study (2010-2012) was designed to evaluate the impacts of manure management and tillage practices on bacteria losses to drainage tiles under a wide range of field conditions. PM was applied annually in spring, prior to planting corn, at application rates ranging from 5 to 40 kg/ha to achieve target rates of 112 and 224 kg/ha nitrogen (PM1 and PM2). Control plots received no manure (PM0). Each treatment was replicated on three chisel-plowed (CP) plots and one no-till (NT) plot. Tile-water grab samples were collected weekly when tiles were flowing beginning 30 days before manure application to 100 days post application, and additional grab samples were obtained to target the full spectrum of flow conditions. Manure and tile-water samples were analyzed for the pathogen, Salmonella spp. (SALM), and fecal indicator bacteria (FIB), Escherichia coli (EC), and enterococci (ENT). All three bacterial genera were detected more frequently, and at significantly higher concentrations, in tile-waters draining NT plots compared to CP plots. Transport of bacteria to NT tiles was most likely facilitated by macropores, which were significantly more numerous above tiles in NT plots in 2012 as determined by smoke-testing. While post-manure samples contained higher concentrations of bacteria than pre-manure samples, significant differences were not seen between low (PM1) and high (PM2) rates of PM application. The highest concentrations were observed under the NT PM2 plot in 2010 (6.6 × 10(3) cfu/100 mL EC, 6.6 × 10(5) cfu/100 mL ENT, and 2.8 × 10(3) cfu/100 mL SALM). Individual and 30-day geometric mean ENT concentrations correlated more strongly to SALM than EC; however, SALM were present in samples with little or no FIB

  20. Long-term Differences in Tillage and Land Use Affect Intra-aggregate Pore Heterogeneity

    SciTech Connect

    Kravchenko, A.N.; Wang, A.N.W.; Smucker, A.J.M.; Rivers, M.L.

    2012-10-25

    Recent advances in computed tomography provide measurement tools to study internal structures of soil aggregates at micrometer resolutions and to improve our understanding of specific mechanisms of various soil processes. Fractal analysis is one of the data analysis tools that can be helpful in evaluating heterogeneity of the intra-aggregate internal structures. The goal of this study was to examine how long-term tillage and land use differences affect intra-aggregate pore heterogeneity. The specific objectives were: (i) to develop an approach to enhance utility of box-counting fractal dimension in characterizing intra-aggregate pore heterogeneity; (ii) to examine intra-aggregate pores in macro-aggregates (4-6 mm in size) using the computed tomography scanning and fractal analysis, and (iii) to compare heterogeneity of intra-aggregate pore space in aggregates from loamy Alfisol soil subjected to 20 yr of contrasting management practices, namely, conventional tillage (chisel plow) (CT), no-till (NT), and native succession vegetation (NS). Three-dimensional images of the intact aggregates were obtained with a resolution of 14.6 {micro}m at the Advanced Photon Source, Argonne National Laboratory, Argonne, IL. Proposed box-counting fractal dimension normalization was successfully implemented to estimate heterogeneity of pore voxel distributions without bias associated with different porosities in soil aggregates. The aggregates from all three studied treatments had higher porosity associated with large (>100 {micro}m) pores present in their centers than in their exteriors. Pores 15 to 60 {micro}m were equally abundant throughout entire aggregates but their distributions were more heterogeneous in aggregate interiors. The CT aggregates had greater numbers of pores 15 to 60 {micro}m than NT and NS. Distribution of pore voxels belonging to large pores was most heterogeneous in the aggregates from NS, followed by NT and by CT. This result was consistent with presence of

  1. Constructing Hardware in a Scale Embedded Language

    Energy Science and Technology Software Center (ESTSC)

    2014-08-21

    Chisel is a new open-source hardware construction language developed at UC Berkeley that supports advanced hardware design using highly parameterized generators and layered domain-specific hardware languages. Chisel is embedded in the Scala programming language, which raises the level of hardware design abstraction by providing concepts including object orientation, functional programming, parameterized types, and type inference. From the same source, Chisel can generate a high-speed C++-based cycle-accurate software simulator, or low-level Verilog designed to pass onmore » to standard ASIC or FPGA tools for synthesis and place and route.« less

  2. Constructing Hardware in a Scale Embedded Language

    SciTech Connect

    Bachan, John

    2014-08-21

    Chisel is a new open-source hardware construction language developed at UC Berkeley that supports advanced hardware design using highly parameterized generators and layered domain-specific hardware languages. Chisel is embedded in the Scala programming language, which raises the level of hardware design abstraction by providing concepts including object orientation, functional programming, parameterized types, and type inference. From the same source, Chisel can generate a high-speed C++-based cycle-accurate software simulator, or low-level Verilog designed to pass on to standard ASIC or FPGA tools for synthesis and place and route.

  3. GY SAMPLING THEORY IN ENVIRONMENTAL STUDIES 1: ASSESSING SOIL SPLITTING PROTOCOLS

    EPA Science Inventory

    Five soil sample splitting methods (riffle splitting, paper cone riffle splitting, fractional shoveling, coning and quartering, and grab sampling) were evaluated with synthetic samples to verify Pierre Gy sampling theory expectations. Individually prepared samples consisting of l...

  4. Energize Yourself and Your Family

    MedlinePlus

    ... activities that strengthen your muscles. Examples include heavy gardening (digging and shoveling) and exercises that use hand ... them, too. Do things you enjoy, like biking, gardening, playing sports, or swimming. Get a friend to ...

  5. Improving Your Health: Tips for African American Men and Women

    MedlinePlus

    ... to reach your goal: walking briskly water aerobics gardening As you become more comfortable, consider adding more ... activities. Examples include these: running aerobic dancing heavy gardening (digging and shoveling) In addition to aerobic activity, ...

  6. 155. Credit ER. Hand cleaning and trimming of Coleman canal ...

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

    155. Credit ER. Hand cleaning and trimming of Coleman canal after excavation by steam shovel. (ER, v. 64 1911 p. 701). - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  7. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  8. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are... may be taken or possessed. (6) Bering Sea Area. (i) In that portion of the area north of the...

  9. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  10. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  11. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  12. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  13. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  14. 36 CFR 242.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited... shell width of 51/2 inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In...

  15. 50 CFR 100.28 - Subsistence taking of shellfish.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A...) Bering Sea Area. (i) In that portion of the area north of the latitude of Cape Newenham, shellfish...

  16. 40 CFR 63.7521 - What fuel analyses and procedures must I use?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) For each composite sample, select a minimum of five sampling locations uniformly spaced over the... flat square shovel into the hole and withdraw a sample, making sure that large pieces do not fall...

  17. DETAIL VIEW OF LARGE BORE HOLE, SHOWING TRIANGULAR SHAPE FORMED ...

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

    DETAIL VIEW OF LARGE BORE HOLE, SHOWING TRIANGULAR SHAPE FORMED BY CHISEL METHOD OF DRILLING - Granite Hill Plantation, Quarry No. 3, South side of State Route 16, 1.3 miles northeast east of Sparta, Sparta, Hancock County, GA

  18. Evaluation of remote sensing in control of pink cotton bollworm

    NASA Technical Reports Server (NTRS)

    Lewis, L. N. (Principal Investigator); Coleman, V. B.

    1973-01-01

    The author has identified the following significant results. The U-2 underflight photography has shown that the critical stages in cotton plow down (defoliation, shredding, and plowing) can be identified. This result will prove invaluable to a user agency whose purpose is to monitor the cotton season for compliance with California State law.

  19. High biomass removal limits carbon sequestration potential of mature temperate pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decades of plowing have depleted organic carbon stocks in many agricultural soils. Conversion of plowed fields to pasture has the potential to reverse this process, recapturing organic matter that was lost under more intensive cropping systems. Temperate pastures in the northeast USA are highly prod...

  20. Is Deep Zone Tillage Agronomically Viable in Minnesota?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deep zone tillage is a strategy used to alleviate compaction problems, such as plow pans, and improve drainage. Midwestern soils rarely have a clearly defined plow-pan. Yields were measured for two seasons after zone tilling replications in a field. Zone till failed to increase corn yields and incre...

  1. 76 FR 77887 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-14

    ...--phase II Master plan update and snow removal requirements analysis Acquire snow plow and spreader...: Security enhancement 1 Security enhancement 2 Pickup mounted snow plow blade Service road rehabilitation... firefighting building Acquire snow removal equipment Acquire interactive training system Acquire snow...

  2. 77 FR 14584 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ... hangar area. Construct apron to new hangar area. Procure snow removal equipment--runway sander and plow... cones. Runway 8/26 pavement rejuvenation. Purchase snow removal equipment--high-speed snow plow. Master... markings. Acquire snow removal equipment with attachments. Acquire security vehicle. Runway 8/26...

  3. Determinants of tillage frequency among smallholder farmers in two semi-arid areas in Ethiopia

    NASA Astrophysics Data System (ADS)

    Temesgen, Melesse; Rockstrom, J.; Savenije, H. H. G.; Hoogmoed, W. B.; Alemu, Dawit

    Traditional tillage systems practiced by farmers in semi-arid regions of Ethiopia are characterized by repeated and cross plowing with an indigenous plow called Maresha. Repeated and cross plowing have led to land degradation. Conservation tillage systems that advocate minimum soil disturbance can alleviate land degradation problems. However, before introducing reduced tillage systems, it was found necessary to study why farmers undertake repeated plowing. The study was undertaken in two semi-arid areas called Melkawoba and Wulinchity located in the central rift valley of Ethiopia and on two major crops; Tef ( Eragrostis Tef (Zucc.)) and maize ( Zea mays XX). Fifty farmers from each area were randomly selected and interviewed using a structured questionnaire. The results showed that farmers in the study area plow repeatedly in order to completely disturb unplowed strips of land left between adjacent furrows. Unplowed strips are the results of the V-shaped furrows created by the Maresha plow. Farmers generally do not plow before the soil is wetted by rainfall. Wetting and drying cycles due to dry spells occurring between rainfall events force farmers to plow frequently to avoid moisture losses through surface runoff, evaporation and weed transpiration. Tef fields are plowed 4-5 times while maize fields are plowed 3-4 times. Tillage frequency increased with the education level and experience of farmers; with their perception about the purpose of tillage such as moisture conservation, weed control and soil warming; and with resource availability such as area of land and family labor. Tillage frequency was higher for Tef than for maize and in heavy soils than in light soils.

  4. Land use and land management effects on soil organic carbon stock in Mediterranean agricultural areas (Southern Spain)

    NASA Astrophysics Data System (ADS)

    Parras-Alcántara, Luis; Lozano-García, Beatriz

    2014-05-01

    INTRODUCTION Soils play a key role in the carbon geochemical cycle. Agriculture contributes to carbon sequestration through photosynthesis and the incorporation of carbon into carbohydrates. Soil management is one of the best tools for climate change mitigation. Small increases or decreases in soil carbon content due to changes in land use or management practices, may result in a significant net exchange of carbon between the soil carbon pool and the atmosphere. In the last decades arable crops (AC) have been transformed into olive grove cultivations (OG) or vineyards (V) in Mediterranean areas. A field study was conducted to determine long-term effects of land use change (LUC) (AC by OG and V) on soil organic carbon (SOC), total nitrogen (TN), C:N ratio and their stratification in Calcic-Chromic Luvisols (LVcc/cr) in Mediterranean conditions. MATERIAL AND METHODS An unirrigated farm in Montilla-Moriles (Córdoba, Spain) cultivated under conventional tillage (animal power with lightweight reversible plows and non-mineral fertilization or pesticides) was selected for study in 1965. In 1966, the farm was divided into three plots with three different uses (AC, OG and V). The preliminary analyses were realized in 1965 for AC (AC1), and the second analyses were realized in 2011 for AC (AC2 - winter crop rotation with annual wheat and barley, receiving mineral fertilization or pesticides), OG (annual passes with disk harrow and cultivator in the spring, followed by a tine harrow in the summer receiving mineral fertilization and weed control with residual herbicides), and V (with three or five chisel passes a year from early spring to early autumn with mineral fertilization or pesticides.). In all cases (AC1, AC2, OG and V) were collected soil entire profiles. Soil properties determined were: soil particle size, bulk density, SOC, TN, C:N ratio, stocks and SRs. The statistical significance of the differences in the variables between land use practices was tested using the

  5. Overland flow connectivity in olive orchard plots with cover crops and conventional tillage, and under different rainfall scenarios

    NASA Astrophysics Data System (ADS)

    López-Vicente, Manuel; García-Ruiz, Roberto; Guzmán, Gema; Vicente-Vicente, José Luis; Gómez, José Alfonso

    2016-04-01

    The study of overland flow connectivity (QC) allows understanding the redistribution dynamics of runoff and soil components as an emergent property of the spatio-temporal interactions of hydrological and geomorphic processes. However, very few studies have dealt with runoff connectivity in olive orchards. In this study we simulated QC in four olive orchard plots, located on the Santa Marta farm (37° 20' 33.6" N, 6° 13' 44" W), in Seville province (Andalusia) in SW Spain. The olive plantation was established in 1985 with trees planted at 8 m x 6 m. Each bounded plot is 8 m wide (between 2 tree lines) and 60 m long (total area of 480 m2), laid out with the longest dimension parallel to the maximum slope and to the tree lines. The slope is uniform, with an average steepness of 11%. Two plots (P2 and P4) were devoted to conventional tillage (CT) consisting of regular chisel plow passes depending on weed growth. Another set of two plots had two types of cover crops (CC) in the inter tree rows (the area outside the vertical olive canopy projection): uniform CC of Lolium multiflorum (P3) and a mixture of L. rigidum and L. multiflorum together with other species (P5). The tree rows were treated with herbicide to keep bare soil. We selected the Index of runoff and sediment Connectivity (IC) of Borselli et al. (2008) to simulate three rainfall scenarios: i) low rainfall intensity (Sc-LowInt) and using the MD flow accumulation algorithm; ii) moderate rainfall intensity (Sc-ModInt) and using MD8; and iii) high rainfall intensity (Sc-HighInt) and using D8. After analysing the values of rainfall intensity during two hydrological years (Oct'09-Sep'10 and Oct'10-Sep'11) we associated the three scenarios with the followings months: Sc-LowInt during the period Jan-Mar, that summarizes 42% of all annual rainfall events; Sc-ModInt during Oct-Nov and Apr-May (32% of all events); and Sc-HighInt during the period Jun-Sep and in December (26% of all events). Instead of using the C

  6. Ethnic variation of selected dental traits in Coorg

    PubMed Central

    Uthaman, Chancy; Sequeira, Peter Simon; Jain, Jithesh

    2015-01-01

    Purpose: In a country like India, in addition to the great innate diversity, there are distinct migrant populations with unique dental traits. Aim: To assess the distribution and degree of expression of cusp of Carabelli of maxillary first permanent molars and shoveling trait of maxillary central incisors, between three ethnic groups of Coorg, namely Kodavas, Tibetans, and Malayalees. Materials and Methods: A cross-sectional, indirect, anthropometric, study was carried out among 15- to 30-year-old subjects belonging to three different ethnic origins. A random sample consisting of 91 subjects were recruited for the study. The shovel trait of incisors and the Carabelli trait of molars were recorded according to the classification given by Hrdliƈka and Sousa et al., respectively. Statistical Analysis: The Kruskal-Wallis test was employed to determine the difference in three populations for shoveling and Carabelli traits. Mann-Whitney Test was used for pair-wise comparisons of three populations. Result: Of the total 91 subjects, 31 were Kodavas, 30 Malayalees and 30 Tibetans. There was a statistically significant difference in shoveling trait among the three ethnic groups. For Carabelli traits, there was no statistically significant difference among three ethnic groups. Conclusion: The present study findings showed that Tibetans have a higher degree of shoveling trait than the selected South Indian ethnic groups. PMID:26816457

  7. Computer-assisted spherical osteotomy with a curved-bladed Tuke Saw.

    PubMed

    Koyama, Tsuyoshi; Sugano, Nobuhiko; Nishii, Takashi; Miki, Hidenobu; Sato, Yoshinobu; Yoshikawa, Hideki; Tamura, Shinichi

    2006-07-01

    Techniques for spherical osteotomy, such as rotational acetabular osteotomy, can help orthopaedic surgeons correct bony deformities and remove spherical acetabular components. Curved chisels are used during a spherical osteotomy, but they require skill and have a potential risk of damaging blood vessels or nerves. In order to perform a precise, quick and safe spherical osteotomy, we have developed a novel computer-assisted surgical tool using a vibrating bone saw, the Tuke Saw, with a curved blade that operates under the guidance of an optical navigation system. In this study, the accuracy and ease of use of this curved-bladed Tuke Saw in spherical osteotomy were examined in comparison with the conventional curved chisel. Using these surgical tools, hemispherical osteotomies were performed on rectangular parallelepiped Sawbones blocks and rotational acetabular osteotomies were performed on cadaveric pelves. The distance error with the curved-bladed Tuke Saw was significantly smaller than that with the curved chisel, and the procedure time with the Tuke Saw was approximately half that with the chisel. It can thus be concluded that the curved-bladed Tuke Saw is more accurate and easier to use than the conventional curved chisel. PMID:17060078

  8. Feeding ecology of waterfowl wintering on evaporation ponds in California

    USGS Publications Warehouse

    Euliss, N.H., Jr.; Jarvis, R.L.; Gilmer, D.S.

    1991-01-01

    We examined the feeding ecology of Northern Pintails (Anas acuta), Northern Shovelers (A. clypeata), and Ruddy Ducks (Oxyura jamaicensis) wintering on drainwater evaporation ponds in California from 1982 through 1984. Pintails primarily consumed midges (Chironomidae) (39.3%) and widegeongrass (Ruppia maritima) nutlets (34.6%). Shovelers and Ruddy Ducks consumed 92.5% and 90.1% animal matter, respectively. Water boatmen (Corixidae) (51.6%), rotifers (Rotatoria) (20.4%), and copepods (Copepoda) (15.2%) were the most important Shoveler foods, and midges (49.7%) and water boatmen (36.0%) were the most important foods of Ruddy Ducks. All three species were opportunistic foragers, shifting their diets seasonally to the most abundant foods given their behavioral and morphological attributes.

  9. Relationship between waterfowl nutrition and condition on agricultural drainwater ponds in the Tulare Basin, California: waterfowl body composition

    USGS Publications Warehouse

    Euliss, N.H., Jr.; Jarvis, R.L.; Gilmer, D.S.

    1997-01-01

    We examined carcass composition and proximate food composition of ruddy ducks (Oxyura jamaicensis), northern shovelers (Anas clypeata), and northern pintails (Anas acuta) wintering on agricultural drainwater ponds in California during 1983-84. Lipids varied seasonally in northern shovelers and northern pintails. Protein did not fluctuate except in ruddy ducks whose protein mass increased over winter, suggesting that some protein was catabolized prior to arrival on wintering areas or that a buildup of protein occurred prior to spring migration. Waterfowl diets varied among species and time, but the nutritional composition of the diets was relatively stable. Ruddy ducks and shovelers consumed mostly animal foods rich in protein (53-60%) and low in Nitrogen Free Extract (NFE)(1-7%). Pintail diets contained more NFE (23-38%) and less protein (14-38%) because of greater consumption of plant foods. Nutritional composition of pintail diets varied with lower protein consumption occurring from November through January.

  10. White Flame Energy switches to backhoes

    SciTech Connect

    Fiscor, S.

    2005-06-01

    The mountaintop coal operator, White Flame Energy has switched to different truck-shovel arrangement. Along with many surface mining operations throughout central Appalachia, the company is using hoe-configured hydraulic excavators as opposed to the traditional front-shovel arrangements. Located in Varney, WV, White Flame Energy uses two Terex O & K mining shovels, an RH170 and an RH 200, which have the capacity to move 2 million cu yards per month from five seams, primarily the Coalburg, Stockton, and No 5 Block and associated rider seams. The article records conversations on the operations with Mike Vines, the general manager, and Don Nicewonder, the owner of White Flame Energy. 2 photos.

  11. Made in Germany

    SciTech Connect

    2005-09-01

    This supplement was prepared in collaboration with the Association of German Mining Machine Manufacturers within VDMA to give an overview of German manufacturers' contribution to the coal industry. It has 18 short papers and a VDMA vendor matrix and directory. Papers include details of MAN Takraf's surface mining equipment, hydraulic shovels and excavators from Komatsu, Liebherr and Terex O & K, Siemens motors and electric control technology in trucks, shovels etc., new technology from DBT, IBS and Wirth, and low emission engines and drives from Deutz and DaimlerCrysler. 2 figs.

  12. Modified ridge splitting and bone expansion osteotomy for placement of dental implant in esthetic zone

    PubMed Central

    Khairnar, Mayur S.; Khairnar, Darshana; Bakshi, Kedar

    2014-01-01

    Ridge splitting with bone expansion is a technique of manipulation of bone to form receptor site for implant without removing any bone from the implant site. Maxillary bone has inherent quality of flexibility which can bemolded to desire location by using series of instrument namely chisels and osteotome. This further improves quality of bone all around implant, at the crest and apex both. This article describes a report of a clinical case with management of bucco-palatal ridge defect with modified ridge splitting and expansion osteotomy technique using chisel and osteotomes in an esthetic zone. PMID:24808709

  13. Modified ridge splitting and bone expansion osteotomy for placement of dental implant in esthetic zone.

    PubMed

    Khairnar, Mayur S; Khairnar, Darshana; Bakshi, Kedar

    2014-01-01

    Ridge splitting with bone expansion is a technique of manipulation of bone to form receptor site for implant without removing any bone from the implant site. Maxillary bone has inherent quality of flexibility which can bemolded to desire location by using series of instrument namely chisels and osteotome. This further improves quality of bone all around implant, at the crest and apex both. This article describes a report of a clinical case with management of bucco-palatal ridge defect with modified ridge splitting and expansion osteotomy technique using chisel and osteotomes in an esthetic zone. PMID:24808709

  14. The Mechanization of Agriculture.

    ERIC Educational Resources Information Center

    Rasmussen, Wayne D.

    1982-01-01

    Discusses technological innovations affecting the economic and social basis of farm life, focusing on trends, farm equipment (plows, reaping tools, tractors, and harvesters), productivity, and influence of computers in all phases of agribusiness. (JN)

  15. Malaria Vaccine Protection Short-Lived in Young Children

    MedlinePlus

    ... a situation where unvaccinated children have more natural immunity than vaccinated children, and therefore get less malaria," ... may allow a person to develop some natural immunity to the parasite, Plowe suggested. "You're basically ...

  16. Malaria Vaccine Protection Short-Lived in Young Children

    MedlinePlus

    ... was published June 30 in the New England Journal of Medicine . SOURCES: Philip Bejon, Ph.D., director, Kenya Medical Research Institute-Wellcome Trust Program, Kilifi, Kenya; Christopher Plowe, ...

  17. 4. CORNICE AND PARAPET DETAIL. IN THE CENTER IS AN ...

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

    4. CORNICE AND PARAPET DETAIL. IN THE CENTER IS AN ANVIL AND A PLOW, SYMBOLIC TOOLS OF THE FARMERS AND MECHANICS - Farmers' & Mechanics' Bank, 427 Chestnut Street, Philadelphia, Philadelphia County, PA

  18. 49 CFR 325.1 - Scope of the rules in this part.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Agency, 40 CFR part 202. (b) Except as provided in paragraph (c) of this section, the rules in this part... police van, or a rescue van, when it is responding to an emergency call; (5) A snow plow in operation;...

  19. 49 CFR 325.1 - Scope of the rules in this part.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Agency, 40 CFR part 202. (b) Except as provided in paragraph (c) of this section, the rules in this part... police van, or a rescue van, when it is responding to an emergency call; (5) A snow plow in operation;...

  20. 49 CFR 325.1 - Scope of the rules in this part.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Agency, 40 CFR part 202. (b) Except as provided in paragraph (c) of this section, the rules in this part... police van, or a rescue van, when it is responding to an emergency call; (5) A snow plow in operation;...

  1. 77 FR 27537 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-10

    .... Runway high speed snow removal broom. Taxiway R extension and road relocation--construction. PFC... rehabilitation, phase I. Purchase airport snow removal truck/plow. Design and construct noise mitigation...

  2. Effects of agricultural tillage and sediment accumulation on emergent plant communities in playa wetlands of the U.S. High Plains.

    PubMed

    O'Connell, Jessica L; Johnson, Lacrecia A; Daniel, Dale W; McMurry, Scott T; Smith, Loren M; Haukos, David A

    2013-05-15

    Identifying community assembly filters is a primary ecological aim. The High Plains, a 30 million ha short-grass eco-region, is intensely cultivated. Cultivation disturbance, including plowing and eroded soil deposition down-slope of plowing, influences plant composition in depressional wetlands, such as playas, within croplands. We evaluated influences of wetland cultivation and sediment deposition on plant composition in playas embedded within croplands (46 plowed and 32 unplowed) and native grasslands (79) across 6 High Plains' states. Sediment accumulation ranged from 7 to 78 cm in cropland and 1 to 35 cm in grassland playas. Deeper sediments and plowing each decreased wetland plant richness, 28% and 70% respectively in cropland wetlands. Sediment depth reduced richness 37% in small grasslands playas while it increased richness 22% in larger ones, suggesting moderate disturbance increased richness when there were nearby propagule sources. Sediment depth was unrelated to species richness in plowed wetlands, probably because plowing was a strong disturbance. Plowing removed perennial plants from vegetation communities. Sediment accumulation also influenced species composition in cropland playas, e.g., probability of Eleocharis atropurpurea increased with sediment depth, while probability of Panicum capillare decreased. In grassland playas, observed lighter sediment depths did not influence species composition after accounting for wetland area. Sediment accumulation and plowing shift wetland plant communities toward annual species and decrease habitat connectivity for wetland-dependent organisms in cropland playas over 39,000 and 23,400 ha respectively. Conservation practices lessening sediment accumulation include short-grass buffer strips surrounding wetlands. Further, wetland tillage, allowed under federal agricultural conservation programs, should be eliminated. PMID:23500104

  3. Sampling for the incidence of aphid-transmitted viruses in snap bean.

    PubMed

    Shah, Denis A; Dillard, Helene R; Nault, Brian A

    2005-12-01

    ABSTRACT Data collected in 2002 and 2003 on Alfalfa mosaic virus and Cucumber mosaic virus incidences of infection in commercial snap bean fields in New York State were used to develop relationships between disease incidence (p(low)) and sample size while accounting for the inherent spatial aggregation of infected plants observed with these two viruses. For a plan consisting of 300 sampled plants (N = 60 quadrats, n = 5 plants per quadrat), estimating p(low) from the incidence of positive groups (p(high); testing of N = 60 grouped samples) provides the same precision in p(low) as testing 200 plants individually, up to about p(low) = 0.2. Above that, the confidence interval width for p(low) obtained via group testing becomes markedly larger than the width obtained by testing individual plants. Our results suggest using group testing until p(high) is in the range [0.35, 0.59], which corresponds to p(low) in [0.1, 0.2]. Results indicate that group testing can be more economical than the testing of individual plants without loss of precision, at lower incidences of infection. The approach presented provides a general framework for sampling and the estimation of incidence of other aphid-transmitted viruses in snap bean. PMID:18943551

  4. Punchy, Munchy...Culinary Curriculum

    ERIC Educational Resources Information Center

    Schmidt, Carolee; And Others

    1977-01-01

    Eating involves--and offers--a lot more than merely shoveling food into your mouth. It can be used in innumerable ways in your room. Here is a multitude of food experiences, all designed for kids' heads as well as their stomachs. You can use cooking and food throughout your curriculum. Here's how! (Editor)

  5. Diesel Engine Technician

    ERIC Educational Resources Information Center

    Tech Directions, 2010

    2010-01-01

    Diesel engine technicians maintain and repair the engines that power transportation equipment such as heavy trucks, trains, buses, and locomotives. Some technicians work mainly on farm machines, ships, compressors, and pumps. Others work mostly on construction equipment such as cranes, power shovels, bulldozers, and paving machines. This article…

  6. 6. AERATOR VIEWED UPSTREAM. DETAIL OF FLUSH VALVE AND VIEW ...

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

    6. AERATOR VIEWED UPSTREAM. DETAIL OF FLUSH VALVE AND VIEW INTO BOX FLUME. NOTE WRENCH TO OPEN VALVE AND REMAINS OF OLD SHOVEL USED FOR MAINTENANCE. TRASH SCREEN MESH IS SEEN AT BOTTOM LEFT. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

  7. VIEW LOOKING NORTHEAST SHOWING THE TRASH GRATE THAT REPLACED THE ...

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

    VIEW LOOKING NORTHEAST SHOWING THE TRASH GRATE THAT REPLACED THE LOCK GATES TO LOCK 71 WHEN THE FLIGHT OF FIVE WAS CONVERTED TO A SPILLWAY AFTER THE LARGER LOCKS, 34 AND 35, WERE PUT INTO OPERATION. THE SHOVEL TRUCK IN THE VIEW IS USED TO CLEAR DEBRIS. - New York State Barge Canal, Lockport Locks, Richmond Avenue, Lockport, Niagara County, NY

  8. Technology for Institutional Enrollment, Communication, and Student Success

    ERIC Educational Resources Information Center

    Salas, Grace; Alexander, Julie S.

    2008-01-01

    Regardless of whether an institution is a reluctant passenger on the racing technology train or itching to throw another shovel of coal on the fire, continuing advancements in technology make it a formidable factor in life on college campuses today. While students are updating their most recent social networking sites, faculty, staff, and…

  9. Winter Weather: Outdoor Safety

    MedlinePlus

    ... If you have heart disease or high blood pressure, follow your doctor’s advice about shoveling snow or performing other hard ... Pack dry clothing, a two-wave radio, waterproof matches and paraffin fire starters with you. Do not use alcohol and ...

  10. 30 CFR 57.12039 - Protection of surplus trailing cables.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Protection of surplus trailing cables. 57.12039... Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar equipment shall be— (a) Stored in cable boats; (b) Stored on...

  11. 30 CFR 57.12039 - Protection of surplus trailing cables.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Protection of surplus trailing cables. 57.12039... Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar equipment shall be— (a) Stored in cable boats; (b) Stored on...

  12. Making a Big Deal about Everyday Objects

    ERIC Educational Resources Information Center

    Masse, Don

    2010-01-01

    Claes Oldenburg and Coosje van Bruggen, who have been married over 30 years, take items from popular culture and transform them into giant sculptures that are on display all over the world. Their installations include clothespins, baseball bats, garden shovels and ice cream cones, to name a few. This transformation of everyday things is a great…

  13. 30 CFR 57.12039 - Protection of surplus trailing cables.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Protection of surplus trailing cables. 57.12039... Electricity Surface and Underground § 57.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar equipment shall be— (a) Stored in cable boats; (b) Stored on...

  14. 75 FR 53598 - Endangered and Threatened Wildlife and Plants; Threatened Status for Shovelnose Sturgeon Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... recruitment, commercial harvest, pollution and contaminants, and hybridization (55 FR 36641, September 6, 1990...) (16 U.S.C. 1531 et seq.) (55 FR 36641, September 6, 1990). The pallid sturgeon has a flattened, shovel... under the Act (55 FR 36641). At the time of listing, the primary threats and vulnerabilities for...

  15. 7 CFR 58.419 - Curd mill and miscellaneous equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., shovels, scoops, paddles, strainers, and miscellaneous equipment shall be stainless steel or of material... of the curd mill should be of stainless steel. All pieces of equipment shall be so constructed that... metal particles. The wires in the curd knives shall be stainless steel, kept tight and replaced...

  16. 7 CFR 58.419 - Curd mill and miscellaneous equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., shovels, scoops, paddles, strainers, and miscellaneous equipment shall be stainless steel or of material... of the curd mill should be of stainless steel. All pieces of equipment shall be so constructed that... metal particles. The wires in the curd knives shall be stainless steel, kept tight and replaced...

  17. 7 CFR 58.419 - Curd mill and miscellaneous equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., shovels, scoops, paddles, strainers, and miscellaneous equipment shall be stainless steel or of material... of the curd mill should be of stainless steel. All pieces of equipment shall be so constructed that... metal particles. The wires in the curd knives shall be stainless steel, kept tight and replaced...

  18. 7 CFR 58.419 - Curd mill and miscellaneous equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., shovels, scoops, paddles, strainers, and miscellaneous equipment shall be stainless steel or of material... of the curd mill should be of stainless steel. All pieces of equipment shall be so constructed that... metal particles. The wires in the curd knives shall be stainless steel, kept tight and replaced...

  19. Over the Fence: Learning about Education for Sustainability with New Tools and Conversation

    ERIC Educational Resources Information Center

    McClam, Sherie; Diefenbacher, Lori

    2015-01-01

    The metaphor of talking "over the fence" underscores the neutrality of tools. Shovels and hoes do the job, but the gardener creates the transformation of earth to food. Each garden requires a unique approach. Such are the tools of education for sustainable development (ESD). Pre-packaged textbooks and toolkits provide definitions and…

  20. Be Active Your Way: A Guide for Adults

    MedlinePlus

    ... you will try): ❑ Biking slowly ❑ Canoeing ❑ Dancing ❑ General gardening (raking, trimming shrubs) ❑ Tennis (doubles) ❑ Using your manual ... activities a couple of days a week: • Heavy gardening (digging,shoveling) • Lifting weights • Push-ups on the ...

  1. Big Jobs: Planning for Competence

    ERIC Educational Resources Information Center

    Jones, Nancy P.

    2005-01-01

    Three- to five-year-olds grow emotionally participating in meaningful and challenging physical, social, and problem-solving activities outdoors in an early childhood program on a farm. Caring for animals, planting, raking, shoveling, and engaging in meaningful indoor activities, under adult supervision, children learn to work collaboratively,…

  2. 4. East portal of Tunnel 17, contextual view to southeast, ...

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

    4. East portal of Tunnel 17, contextual view to southeast, 135mm lens. This end of the tunnel was badly damaged during construction in April 1909 by a disgruntled worker who set off a heavy powder charge, injuring fellow workers and destroying a steam shovel. - Southern Pacific Railroad Natron Cutoff, Tunnel No. 17, Milepost 408, Dorris, Siskiyou County, CA

  3. Prevalence of aberrant dental morphological details in 6-10 year old school children in an Indian population

    PubMed Central

    Kirthiga, M.; Manju, M.; Praveen, R.; Umesh, W.

    2015-01-01

    Background: Variations in the structure of teeth have always been a great curiosity to the dentist from the scientific and practical point of view. Aim: To evaluate the prevalence of a few aberrant morphological features namely, cusp of Carabelli in primary maxillary second molar and in permanent first molar, five cusp in primary maxillary second molar and permanent first molar, shoveling and double shoveling with respect to permanent maxillary central incisors, four cusped primary mandibular second molar and permanent first molar, six cusped primary mandibular second molar and permanent first molar and seven cusped primary mandibular second molar and permanent first molar in 6–10 year old children belonging to the East Bengaluru, a City in India. Design: A cross-sectional survey was conducted among 2111 children by two stage sampling method. Type III examination was performed. The findings were subjected to Chi-square test. Results: 83.8% of the studied population had one or more of the variations checked for, as mentioned above. The variation most commonly seen was double shoveling (66.6%) followed by shoveling (65.7%). No significant results were observed in any trait with respect to gender. Conclusion: This study is the first of its kind, providing a baseline data of the prevalence of morphological details in the pediatric Indian population. PMID:26604571

  4. HUNTER 10, TRUFLO GONDOLA WEIGHTS AND JACKET. PIVOTING ARMS RAISE ...

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

    HUNTER 10, TRUFLO GONDOLA WEIGHTS AND JACKET. PIVOTING ARMS RAISE THE JACKET AND WEIGHTS. A PNEUMATIC SHOVEL PUSHES THE MORE RECENTLY POURED MOLD INTO THE COOLED MOLD, FORCING THE LATTER ONTO THE VIBRATING SHAKEOUT CONVEYOR AND LEAVING A SPACE UNDER THE RAISED JACKET AND WEIGHTS FOR A FRESHLY MADE UNPOURED MOLD. - Southern Ductile Casting Company, Casting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  5. 2006 Haulage & Loading Conference: big equipment, big crowd

    SciTech Connect

    2006-06-15

    The theme of this year's Haulage and Loading Conference was 'Is better still better?' Most of the presenters either considered the effectiveness of bigger equipment or examined other strategies from various perspectives, based on their experiences. Papers were presented on trucks, shovels, loaders, excavators, haul road design and maintenance, and incorporating IT equipment. 5 photos.

  6. 28. HULETT NO. 4 SEEN FROM THE DECK OF THE ...

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

    28. HULETT NO. 4 SEEN FROM THE DECK OF THE 'GEORGE M. CARL.' THE END OF UNLOADING, TRACTOR SCRAPERS ARE LOWERED INTO THE HOLD TO 'CLEAN UP.' PRIOR TO ABOUT 1953, MEN WITH SHOVELS DID THE JOB. - Pennsylvania Railway Ore Dock, Lake Erie at Whiskey Island, approximately 1.5 miles west of Public Square, Cleveland, Cuyahoga County, OH

  7. 56. Photographic copy of historic photo, 1911 (original print filed ...

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

    56. Photographic copy of historic photo, 1911 (original print filed in Record Group 115, National Archives, Washington, D.C.). STEAM SHOVEL EXCAVATING GRAVEL FOR FACING LOWER DEER FLAT EMBANKMENT. - Boise Project, Deer Flat Embankments, Lake Lowell, Nampa, Canyon County, ID

  8. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05761, Marion Power Shovel Company, October 1963. CRAWLER TRUCK ASSEMBLY-FIELD WELDMENT SECTIONS & DETAILS. Sheet 4 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  9. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05761, Marion Power Shovel Company, October 1963. CRAWLER TRUCK ASSEMBLY-SIDE VIEW. Sheet 3 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  10. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05761, Marion Power Shovel Company, October 1963. CRAWLER TRUCK ASSEMBLY-PLAN VIEW. Sheet 2 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  11. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05770, Marion Power Shovel Company, February 1964. OPERATOR'S CAB ASSY. Sheet 1 of 1 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  12. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05760, Marion Power Shovel Company, January 1965. GENERAL ARRANGEMENT. Sheet 3 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  13. Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John ...

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

    Photocopy of drawing. LAUNCH COMPLEX 39, CRAWLER TRANSPORTER. NASA, John F. Kennedy Space Center, Florida. Drawing 75M05762, Marion Power Shovel Company, December 1964. CHASSIS STRUCTURE ASSEMBLY. Sheet 2 - Cape Canaveral Air Force Station, Launch Complex 39, Crawler Transporters, Launcher Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  14. Teaching Literacy in the Technology Classroom

    ERIC Educational Resources Information Center

    Panell, Chris

    2005-01-01

    A technology instructor's job is not to simply "shovel out" knowledge; they must inspire students to seek out information on their own. Their mission is to prepare students for success in the workplace in the shortest practical time, and one of these workplace requirements is the ability to read and research on the job. Although most technology…

  15. Cold, Ice, and Snow Safety (For Parents)

    MedlinePlus

    ... to Know About Zika & Pregnancy Cold, Ice, and Snow Safety KidsHealth > For Parents > Cold, Ice, and Snow Safety Print A A A Text Size What's ... a few. Plus, someone has to shovel the snow, right? Once outdoors, however, take precautions to keep ...

  16. Basic Hand Tools for Bricklaying and Cement Masonry [and] Basic Hand Tools of the Carpenter.

    ERIC Educational Resources Information Center

    Texas A and M Univ., College Station. Vocational Instructional Services.

    Intended for student use, this unit discusses and illustrates the tools used in brick and masonry and carpentry. Contents of the brick and masonry section include informative materials on bricklaying tools (brick trowels, joint tools, levels, squares, line and accessories, rules, hammers and chisels, tool kits) and cement masonry tools (tampers,…

  17. Comparison of surface emissions and subsurface distribution of cis- and trans-1,3-dichloropropene and chloropicrin in sandy field beds covered with four different plastic films

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiment was conducted at a Florida sandy soil field site to study surface emissions and subsurface distribution of cis- and trans-1,3-dichloropropene (1,3-D) and chloropicrin (CP). Sixteen raised beds were applied with Telone C35 by chisel injection and covered with 4 different plastic films (bla...

  18. Describing Polygonum aviculare emergence in different tillage systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of four tillage systems (direct drill, subsoiler, chisel plough and mouldboard plough) on the dynamics of Polygonum aviculare populations were studied over three growing seasons. Densities before and after herbicide application and cumulative emergence on a weekly basis were determined in ea...

  19. Soil and crop nitrogen as influenced by tillage, cover crops, and nitrogen fertilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil and crop management practices may influence soil mineral N, crop N uptake, and N leaching. We evaluated the effects of three tillage practices [no-till (NT), strip till (ST), and chisel till (CT)], four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)],...

  20. Cutting Tools, Files and Abrasives. Pre-Apprenticeship Phase 1 Training.

    ERIC Educational Resources Information Center

    Lane Community Coll., Eugene, OR.

    This self-paced student training module on cutting tools, files, and abrasives is one of a number of modules developed for Pre-apprenticeship Phase 1 Training. Purpose of the module is to enable students to identify and explain the proper use and care of various knives, saws, snips, chisels, and abrasives. The module may contain some or all of the…

  1. Short-term stover, tillage, and nitrogen management affect near-surface soil organic matter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn (Zea mays L.) stover removal for biofuel or forage has implications on soil organic C (SOC). The objective of this study was to evaluate short-term (3-yr) stover management (retained or removed [79 removed, across treatments and years]), tillage system (chisel tillage, strip-tillage, and no-til...

  2. Evaluation of strip-tillage and fertilizer placement in Southern Idaho corn production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strip tillage (ST) and associated nutrient placement can potentially help producers reduce fuel and machinery costs, increase yield, and reduce soil erosion compared to chisel tillage (CT). This study was initiated to evaluate corn production (Zea mays L.) under ST and CT, and various nitrogen (N) ...

  3. The sensory mechanism in human dentin as revealed by evaporation and mechanical removal of dentin.

    PubMed

    Brännström, M; Johnson, G

    1978-01-01

    Dentinal pain in connection with mechanical stimulation i.e. probing, chiseling and initial drilling may be due to removal of fluid from the dentinal tubules. Loss of fluid due to "normal" evaporation from exposed dentin may produce an outward flow in the dentinal tubules rapid enough to cause pain and within a few minutes odontoblast aspiration. PMID:277500

  4. Teaching with Technology: Enhancing Student Projects.

    ERIC Educational Resources Information Center

    Allen, Denise

    1995-01-01

    Reviews four software programs and describes features that illustrate their creative and utility value: (1) "ClarisWorks" for presentation purposes; (2) "Easy Book" for putting books together; (3) "Nutribase Personal Nutrition Manager" for nutrition education, and (4) "Digital Chisel" for interactive lessons, tests, and storybooks. Identifies…

  5. Long and short-term tillage effects on Heterodera glycines reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Investigations were conducted to determine the long and short-term effects of tillage on Heterodera glycines, soybean cyst nematode (SCN), reproduction. Tillage plots were established in 1979 representing six tillage/no-tillage regimes. A portion of each plot was changed from no-tillage to chisel or...

  6. Annual Research Review: Parenting and Children's Brain Development--The End of the Beginning

    ERIC Educational Resources Information Center

    Belsky, Jay; de Haan, Michelle

    2011-01-01

    After questioning the practical significance of evidence that parenting influences brain development--while highlighting the scientific importance of such work for understanding "how" family experience shapes human development--this paper reviews evidence suggesting that brain structure and function are "chiselled" by parenting. Although the…

  7. Global Warming Potential of Organic and Conventional Grain Cropping Systems in the mid-Atlantic Region of the U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The global warming potential (GWP) of a cropping system is the balance between the net exchange of the greenhouse gases CO2, N2O and CH4 that result from on-farm practices and the production and transport of inputs. We report here on GWP calculations for no-till (NT), chisel till (CT) and organic (O...

  8. TILLAGE-INDUCED CO2 LOSS ACROSS A LANDSCAPE AFTER 30 YEARS OF INTENSIVE TILLAGE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil carbon (C)losses and soil translocation from tillage operations have been identified as causes of soil degradation and soil erosion that may contribute to global climate change. The objective of this work was to quantify the variability in tillage-induced CO2 loss by moldboard and chisel plowin...

  9. ACCUMULATION AND CROP UPTAKE OF SOIL MINERAL NITROGEN AS INFLUEMCED BY TILLAGE, COVER CROPS, AND NITROGEN FERTILIZATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil and crop management practices may influence soil mineral N, crop N uptake, and N leaching. We evaluated the effects of three tillage practices [no-till (NT), strip till (ST), and chisel till (CT)], four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secaele cereale L.)]...

  10. Phenology and Abundance of Bean Leaf Beetle (Coleoptera: Chrysomelidae) in Eastern South Dakota on Alfalfa and Soybean Relative to Tillage, Fertilization and Yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenology and abundance of bean leaf beetles, Cerotoma trifurcata (Förster), were examined throughout two eastern South Dakota growing seasons in relation to grain yields in chisel- and ridge-tilled soybeans [Glycine max (L.) Merrill] grown in 2-yr rotation with corn (Zea mays L.) with and without a...

  11. Tillage and Water Deficit Stress Effects on Corn (Zea mays, L.) Root Distribution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One goal of soil management is to provide optimum conditions for root growth. Corn root distributions were measured in 2004 from a crop rotation – tillage experiment that was started in 2000. Corn was grown either following corn or following sunflower with either no till or deep chisel tillage. Wate...

  12. Woodworking. A Bilingual Text = Carpinteria. Un Texto Bilingue.

    ERIC Educational Resources Information Center

    Los Angeles Unified School District, CA. Div. of Career and Continuing Education.

    This booklet is a course of instruction in woodworking in a two-column, English-Spanish format. Following an introduction to woodworking and a lesson on safety, the booklet contains 19 units covering the following topics: wood; planning; laying out project parts; hand saws; planes; chisels and gouges; wood files and forming tools; boring holes in…

  13. TILLAGE, COVER CROPS, AND NITROGEN FERTILIZATION EFFECTS ON SOIL NITROGEN AND COTTON AND SORGHUM YIELDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable soil and crop management practices that reduce soil erosion and nitrogen (N) leaching, conserve soil organic matter, and optimize cotton and sorghum yields still remain a challenge. We examined the influence of three tillage practices (no-till, strip till, and chisel till ), four cover c...

  14. A New Grid Bar Design for a Modified Cylinder Cleaner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grid bars having a chisel shape and sharp cutting edge were designed and installed in a modified cylinder cleaner. The modified cleaner’s seed cotton and lint cleaning performances were evaluated in two tests. Results indicated that seed-cotton cleaning efficiency of the modified cylinder cleaner ...

  15. Changes in the content and quality of humus in leached chernozems of the Trans-Ural forest-steppe zone under the impact of their agricultural use

    NASA Astrophysics Data System (ADS)

    Eremin, D. I.

    2016-05-01

    The results of long-term studies of changes in the content and fractional-group composition of humus in leached chernozems (Luvic Voronic Chernozems, WRB 2006) of the Trans-Ural forest-steppe since the beginning of their plowing are considered. These soils are characterized by the high humus pool (up to 500 t/ha in the virgin state and up to 430 t/ha in the plowed state) and the high degree of the organic matter humification. Humus is of the fulvate-humate type in the upper 30 cm and of the humate-fulvate type in the deeper layers. From 1968 to 2006, the total pool of humus in the 1-m-deep soil layer of the plowed chernozems decreased by 8.5% in comparison with the initial virgin soils. The rate of dehumification reached 1.0-1.4 t/ha per year. The long-term plowing of leached chernozems also led to a smaller content of nitrogen in the organic matter (the C/N ratio increased from 11.5 to 13.6). The relative content of free humic acids (HA-1) and humic acids bound to clay minerals (HA-3) increased, whereas the content of calcium humates (HA-2) decreased. The composition of fulvic acids in the plow horizon was characterized by the rise in the content of aggressive (FA-1a) and mobile (FA-1) fractions, while the amount of fulvates bound to calcium (FA-2) decreased.

  16. Soil cultivation for enhanced wastewater infiltration in soil aquifer treatment (SAT)

    NASA Astrophysics Data System (ADS)

    Nadav, Itamar; Tarchitzky, Jorge; Chen, Yona

    2012-11-01

    SummarySoil aquifer treatment is often employed as a tertiary treatment component of reclamation proceeding of wastewater for irrigation in agriculture. Reductions in infiltration rates due to increase in water repellency have been reported to be associated with organic matter (OM) accumulation in the soil (mainly in the top soil layer) as a result of treated wastewater (TWW) infiltration. Our aim was to reduce OM content in soils extensively loaded with TWW. Four model infiltration ponds were built to simulate large infiltration basins: three for TWW infiltration using different application regimes, and the fourth for freshwater (FW) infiltration (control). We examined changes in OM content, hydraulic conductivity (HC) and water repellency in these model ponds as a result of soil plowing. In field experiment, four soil-plowing events were performed. Reduced OM content and water repellency, and increased HC were found in all TWW-applied ponds following each soil plowing. These changes were attributed to OM burial in deeper soil layers elimination of the continuity of the OM based crust, and surface exposure of soil with low OM content. An overall reduction in OM content was found at the end of the experiment in all soil layers as a consequence of plowing. No changes in OM content, water repellency or HC were found in the FW-applied pond as a result of soil plowing.

  17. Stationary engineering handbook

    SciTech Connect

    Petrocelly, K.L.

    1989-01-01

    Years ago, the only qualifications you needed to become to become an operating engineer were the ability to shovel large chunks of coal through small furnace doors and the fortitude to sweat profusely for hours without fainting. As a consequence of technological evolution, the engineer's coal shovels have been replaced with computers and now perspiration is more the result of job stress than exposure to high temperatures. The domain of the operator has been extended far beyond the smoke-filled caverns that once encased him, out into the physical plant, and his responsibilities have been expanded accordingly. Unlike his less sophisticated predecessor, today's technician must be well versed in all aspects of the operation. The field of power plant operations has become a full-fledged profession and its principals are called Stationary Engineers. This book addresses the areas of responsibility and the education and skills needed for successful operation of building services equipment.

  18. Autoerotic fatalities with power hydraulics.

    PubMed

    O'Halloran, R L; Dietz, P E

    1993-03-01

    We report two cases in which men used the hydraulic shovels on tractors to suspend themselves for masochistic sexual stimulation. One man developed a romantic attachment to a tractor, even giving it a name and writing poetry in its honor. He died accidentally while intentionally asphyxiating himself through suspension by the neck, leaving clues that he enjoyed perceptual distortions during asphyxiation. The other man engaged in sexual bondage and transvestic fetishism, but did not purposely asphyxiate himself. He died when accidentally pinned to the ground under a shovel after intentionally suspending himself by the ankles. We compare these cases with other autoerotic fatalities involving perceptual distortion, cross-dressing, machinery, and postural asphyxiation by chest compression. PMID:8454997

  19. The earliest herbivorous marine reptile and its remarkable jaw apparatus.

    PubMed

    Chun, Li; Rieppel, Olivier; Long, Cheng; Fraser, Nicholas C

    2016-05-01

    Newly discovered fossils of the Middle Triassic reptile Atopodentatus unicus call for a radical reassessment of its feeding behavior. The skull displays a pronounced hammerhead shape that was hitherto unknown. The long, straight anterior edges of both upper and lower jaws were lined with batteries of chisel-shaped teeth, whereas the remaining parts of the jaw rami supported densely packed needle-shaped teeth forming a mesh. The evidence indicates a novel feeding mechanism wherein the chisel-shaped teeth were used to scrape algae off the substrate, and the plant matter that was loosened was filtered from the water column through the more posteriorly positioned tooth mesh. This is the oldest record of herbivory within marine reptiles. PMID:27386529

  20. The Location of the Maximum Temperature on the Cutting Edges of a Drill

    SciTech Connect

    Bono, M J; Ni, J

    2005-01-07

    This study analyzes the temperature profile along the cutting edges of a drill and describes how the temperature on the chisel edge can exceed the temperature on the primary cutting edges. A finite element model predicts the temperature distribution in the drill, where the heat flux loads applied to the finite element model are determined from analytical equations. The model for the heat flux loads considers both the heat generated on the shear plane and the heat generated on the rake face of the tool to determine the amount of heat flowing into the tool on each segment of the cutting edges. Contrary to the conventional belief that the maximum temperature occurs near the outer corner of the drill, the model predicts that the maximum temperature occurs on the chisel edge, which is consistent with experimental measurements of the temperature profile.

  1. The earliest herbivorous marine reptile and its remarkable jaw apparatus

    PubMed Central

    Chun, Li; Rieppel, Olivier; Long, Cheng; Fraser, Nicholas C.

    2016-01-01

    Newly discovered fossils of the Middle Triassic reptile Atopodentatus unicus call for a radical reassessment of its feeding behavior. The skull displays a pronounced hammerhead shape that was hitherto unknown. The long, straight anterior edges of both upper and lower jaws were lined with batteries of chisel-shaped teeth, whereas the remaining parts of the jaw rami supported densely packed needle-shaped teeth forming a mesh. The evidence indicates a novel feeding mechanism wherein the chisel-shaped teeth were used to scrape algae off the substrate, and the plant matter that was loosened was filtered from the water column through the more posteriorly positioned tooth mesh. This is the oldest record of herbivory within marine reptiles. PMID:27386529

  2. Tillage energy savings from zone burial of shredded and whole cotton stalks

    SciTech Connect

    Carter, L.; Chesson, J.; Thacker, G.; Penner, V.

    1996-04-01

    Two prototypes of a stalk burial implement were tested for energy requirements at the University of California, Shafter Research Station. Both versions of the implement are designed to bury the cotton stalks in a concentrated Zone and reform the bed in the same location. To plow under shredded stalks, both versions of the implement required less energy than a conventional tillage systems typical of the San Joaquin Valley of California. Both stalk burial implements were also used to plow under whole cotton stalks. This offers additional energy savings by eliminating the stalk shredding operation.

  3. Correlates of lifetime reproductive success in three species of European ducks.

    PubMed

    Blums, Peter; Clark, Robert G

    2004-06-01

    Number of breeding attempts is a strong correlate of lifetime reproductive success (LRS) in birds, but the relative importance of potentially interacting factors affecting LRS has rarely been fully evaluated. We considered simultaneously five main factors hypothesized to influence LRS (age at first breeding, nesting date, number of breeding attempts, female traits, brood parasitism) by analyzing with path analysis 22-year data sets for 1,279 individually marked females and their offspring in tufted duck ( Aythya fuligula), common pochard ( A. ferina) and northern shoveler (Anas clypeata). We recaptured marked offspring as breeding adults (n=496 females) and obtained more complete estimates of LRS by incorporating information about banded ducklings of both sexes shot by hunters > or =12 months after banding (n=138). In tufted ducks and especially pochard (both diving duck species), late-hatched females tended to delay nesting until 2-years old. Most females (tufted duck, 74%; pochard, 71%; shoveler, 59%) apparently produced no breeding-age offspring. Number of breeding attempts (i.e., longevity) was the strongest correlate of LRS in all species, after controlling effects of age at first breeding, relative nest initiation date, wing length and body mass. Percentage of females producing recruits increased gradually with number of breeding attempts for all three species. Also, as expected, females nesting early in the breeding season had higher LRS than late-nesting individuals. In shoveler, female-specific characteristics of relatively longer wings and heavier late incubation body mass had positive effects on LRS, the latter feature being more common in 2-year-old nesters. In diving ducks, no relationships were detected between LRS and female-specific traits like wing length or body mass, and nor did acceptance of parasitic eggs have any deleterious impact on fitness estimates. Overall, number of fledged ducklings and LRS were related in tufted duck, weakly associated

  4. 59. Photographic copy of historic photo, April 25, 1907 (original ...

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

    59. Photographic copy of historic photo, April 25, 1907 (original print filed in Record Group 115, National Archives, Washington, D.C.). UPPER DEER FLAT EMBANKMENT. STEAM SHOVEL NO. 1 AT WORK ON EASTERLY BORROW PIT. CLASS OF MATERIAL BEING EXCAVATED IS LARGELY SAND AND GRAVEL, WITH ENOUGH CLAY TO FORM A BOND BETWEEN SAND AND GRAVEL. - Boise Project, Deer Flat Embankments, Lake Lowell, Nampa, Canyon County, ID

  5. 13. Coal ejectors mounted on aft bulkhead of coal bunker. ...

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

    13. Coal ejectors mounted on aft bulkhead of coal bunker. Ejectors were used to flush overboard live coals and clinkers from firebed (pipe for carrying coals overboard has been removed from ejector in foreground). Coal doors from bunker appear beside ejector in foreground). Coal doors from bunker appear beside ejectors at deck; note firing shovels in background against hull. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

  6. Age-specific survival and philopatry in three species of European ducks: a long-term study

    USGS Publications Warehouse

    Blums, P.; Mednis, A.; Bauga, I.; Nichols, J.D.; Hines, J.E.

    1996-01-01

    Capture-recapture and band recovery models were used to estimate age-specific survival probabilities for female Northern Shovelers (Anas clypeata), Common Pochards (Aythya ferina), and Tufted Ducks (Aythya.fuligula) at Engure Marsh, Latvia, in 1964-1993. We banded more than 65,100 day-old ducklings of both sexes and captured 10,211 incubating females (3,713 new bandings and 6,498 recaptures). We developed a set of 3-age capture-recapture models to estimate annual survival rates for female ducklings, yearlings (SY), and adults (ASY) using programs SURGE and SURVIV and selected parsimonious models using a method developed bv Akaike (1973). Survival rates of SY and ASY females were highest-for Tufted Ducks intermediate for Common Pochards, and lowest for Northern Shovelers. Survival rates of SY and ASY females varied in parallel for shovelers and pochards. We believe that much of the difference in survival estimates between SY and ASY birds was caused by mortality rather than permanent emigration. Estimates of day-old duckling survival, reflecting both mortality and permanent emigration, were 0.12 for shoveler, 0.06 for pochard, and 0.03 for Tufted Duck. For all species, duckling survival varied over years, but the pattern of variation was not similar to that of the other age classes. Estimates of survival using band recovery data for SY + ASY female pochards and Tufted Ducks were similar to the capture-recapturee stimates, suggestingt hat surviving females returned to the breeding marsh with probabilities approaching 1.

  7. Art Curriculum That Works. Art for Your Summer Vacation

    ERIC Educational Resources Information Center

    Healy, John W.

    2005-01-01

    Kids can pack their shovel and pail, slather on the sunscreen and get ready to create their best artwork yet this summer. Art can be the one activity that you can take to the beach, the lake and special faraway places this summer. Being an artist on your vacation is an added dimension to how you see and experience the world you visit during this…

  8. Improving haul truck productivity

    SciTech Connect

    Fiscor, S.

    2007-06-15

    The paper reviews developments in payload management and cycle times. These were discussed at a roundtable held at the Haulage and Loading 2007 conference held in May in Phoenix, AZ, USA. Several original equipment manufacturers (OEMs) explaind what their companies were doing to improve cycle times for trucks, shovels and excavators used in surface coal mining. Quotations are given from Dion Domaschenz of Liebherr and Steve Plott of Cat Global Mining. 4 figs.

  9. Bucyrus say HydraCrowd could generate revenue

    SciTech Connect

    2009-03-15

    Amongst news of new products from US suppliers is the announcement by Bucyrus International of HydraCrowd which eliminates the need for rope crowd change intervals in electric shovels. Active Control Technology has had its Wi-Fi mesh network system for underground communications and tracking system approved by the MSHA. The Spatial Solutions Division of Leica Geosystems has gone into partnership with Maptek to supply laser scanners and associated mine scanning software. 2 photos.

  10. 60. Photographic copy of historic photo, April 25, 1907 (original ...

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

    60. Photographic copy of historic photo, April 25, 1907 (original print filed in Record Group 115, National Archives, Washington, D.C.). UPPER DEER FLAT EMBANKMENT. STEAM SHOVEL NO. 1 LOADING CARS IN EASTERLY BORROW PIT. CARS IN THIS TRAIN OF 12 NEARLY ALL LOADED. EAIGHT MINUTES REQUIRED TO LOAD 12 CARS EQUAL TO 42 CU YDS. PLACE MEASUREMENT. - Boise Project, Deer Flat Embankments, Lake Lowell, Nampa, Canyon County, ID

  11. Toolmark identification of a mattock to a clod of soil from a grave.

    PubMed

    Clark, Michael D

    2011-01-01

    At a recent bushland gravesite that contained a deceased male, a clod of soil displaying a striated toolmark was collected during the excavation of the grave. This clod was preserved, and the mark was cast using Mikrosil™. Shovels and a mattock, which had been discarded by the suspects, were subsequently found at another location. A toolmark comparison identified the hoe end of the mattock head as having produced the striated toolmark. PMID:20735700

  12. 62. Photographic copy of historic photo, April 25, 1907 (original ...

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

    62. Photographic copy of historic photo, April 25, 1907 (original print filed in Record Group 115, National Archives, Washington, D.C.). UPPER DEER FLAT EMBANKMENT. VIEW FROM EASTERLY END OF EMBANKMENT UNDER CONSTRUCTION. TRAIN IN FOREGROUND RETURNING TO EASTERLY BORROW PIT. STEAM SHOVEL NO.2 IN DISTANCE AT WORK IN WESTERLY BORROW PIT. - Boise Project, Deer Flat Embankments, Lake Lowell, Nampa, Canyon County, ID

  13. Frequency and variability of dental morphology in deciduous and permanent dentition of a Nasa indigenous group in the municipality of Morales, Cauca, Colombia

    PubMed Central

    Díaz, Eider; García, Lorena; Hernández, Michelle; Palacio, Lesly; Ruiz, Diana; Velandia, Nataly; Villavicencio, Judy

    2014-01-01

    Objectives: To determine the frequency, variability, sexual dimorphism and bilateral symmetry of fourteen dental crown traits in the deciduous and permanent dentition of 60 dental models (35 women and 25 men) obtained from a native, indigenous group of Nasa school children of the Musse Ukue group in the municipality of Morales, Department of Cauca, Colombia. Methods: This is a quantitative, descriptive, cross-sectional study that characterizes dental morphology by means of the systems for temporary dentition from Dahlberg (winging), and ASUDAS (crowding, reduction of hypocone, metaconule and cusp 6), Hanihara (central and lateral incisors in shovel-shape and cusp 7), Sciulli (double bit, layered fold protostylid, cusp pattern and cusp number) and Grine (Carabelli trait); and in permanent dentition from ASUDAS (Winging, crowding, central and lateral incisors in shovel-shape and double shovel-shape, Carabelli trait, hypocone reduction, metaconule, cusp pattern, cusp number, layered fold protostylid, cusp 6 and cusp 7). Results: The most frequent dental crown features were the shovel-shaped form, grooved and fossa forms of the Carabelli trait, metaconule, cusp pattern Y6, layered fold, protostylid (point P) and cusp 6. Sexual dimorphism was not observed and there was bilateral symmetry in the expression of these features. Conclusions: The sample studied presented a great affinity with ethnic groups belonging to the Mongoloid Dental Complex due to the frequency (expression) and variability (gradation) of the tooth crown traits, upper incisors, the Carabelli trait, the protostylid, cusp 6 and cusp 7. The influence of the Caucasoide Dental Complex associated with ethno-historical processes cannot be ruled out. PMID:24970955

  14. Sugar cane management with humic extract and organic and mineral fertilizer: impacts on Oxisol some physical properties

    NASA Astrophysics Data System (ADS)

    Alves, M. C.; Campos, F. S.; Souza, Z. M.

    2012-04-01

    The present investigation has as objective to study the impact of cultive systems, humic extract and organic and mineral fertilizers on Oxisol some physical properties cultivated of sugar cane. It was developed in Aparecida do Taboado, Mato Grosso do Sul, Brazil, in Manufactores Alcoolvale. The study was in sugar cane culture implanted on 3th and 4th cycle. The experimental design was at randomized blocks following scheme in zone with eight treatments and four replications. The two treatments in main zone were represented by cultivation systems (with and without chisel) and the subzone fertilization (T1-mineral, T2-mineral+sugar cane residue, T3-mineral+humic and fulvic acids and T4-mix of mineral, sugar cane residue and humic and fulvic acids). In three soil layers: 0.00-0.05; 0.10-0.20 and 0.20-0.40 m were studied the physical soil properties: macroporosity, microporosity, total porosity and soil bulk density. Also evaluate the technological quality of sugar cane. The conclusions are: the application of mineral fertilizer+sugar cane residue+humic extract (Humitec ®) and cropping system with chisel were more effective in improving soil physical; the system of crop of sugar cane ratton implanted in the 2th and 3th cycle, without the use of chisel was better in the recovery of soil physical properties; the crop system without the chisel and the combination of mineral fertilizer+sugar cane residue was promising to increase of Brix, Pol juice, Pol sugar cane and total recoverable sugars Pol.

  15. Optical coherence tomography to evaluate the interaction of different edge designs of four different silicone hydrogel lenses with the ocular surface

    PubMed Central

    Turhan, Semra Akkaya; Toker, Ebru

    2015-01-01

    Purpose To evaluate the lens edge interaction with the ocular surface with different edge designs using optical coherence tomography and to examine the effect of lens power on the lens edge interactions. Methods Four types of silicone hydrogel lenses with different edge designs (round-, semi-round-, chisel-, and knife-edged) at six different powers (+5.0, +3.0, +1.0, −1.0, −3.0, and −5.0 diopters) were fitted to both eyes of 20 healthy volunteers. Optical coherence tomography images were taken at the corneal center and at the limbus within 15–30 minutes after insertion. The images were evaluated with respect to two parameters: conjunctival indentation exerted by the lens edge; and the tear film gaps between the posterior surface of the lens and the ocular surface. The amount of conjunctival indentation was measured with the distortion angle of the conjunctiva at the lens edge. Results The degree of conjunctival indentation was highest with the chisel-edged design followed by the semi-round design (P<0.0001). Knife- and round-edged lenses exerted similar levels of conjunctival indentation that was significantly lower compared to chisel-edged lens (P<0.001). For each one of the tested lens edge designs, no significant difference was observed in the conjunctival indentation with respect to lens power. The chisel-edged lens produced the highest amount of conjunctival indentation for each one of the six lens powers (P<0.0001). Post-lens tear film gaps at the limbus were observed at most in the round-edge design (P=0.001). Conclusion The fitting properties of contact lenses may be influenced by their edge design but not by their lens power. PMID:26045658

  16. 17. A closeup detail, looking east from the northeast corner ...

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

    17. A close-up detail, looking east from the northeast corner of the roadbed. This image shows the concrete commemorative inscription which is let into the inside of the eastern balustrade at the north end of the bridge. The name of one of the county commissioners has been chiselled out of the inscription. The parting fault between the parapet and its coping is evident. - Vigo County Bridge No. 139, Spanning Sugar Creek at Seventy-fourth Place, Terre Haute, Vigo County, IN

  17. Scanning electron microscopy of egg hatching of Anopheles albimanus (Diptera: Culicidae).

    PubMed

    Rodriguez, M H; Orozco, A; Chavez, B; Martinez-Palomo, A

    1992-09-01

    Scanning electron and light microscopic observations showed that egg hatching in Anopheles albimanus Wiedemann is aided by a chisel-shaped spine. This hatching tooth is surrounded by a thin flexible membrane fixed to a groove in the head of the larvae. Increased intracranial pressure may force the spine against the egg shell until a fissure is produced. Further opening of the egg is achieved by movements of the head and the entire body of the larva. PMID:1404271

  18. Paint Scaler. Innovative Technology Summary Report

    SciTech Connect

    2000-06-01

    The Paint Scaler can collect paint samples quickly and efficiently for lab analysis. The Rotary Hammer Drill is a 24-V battery operated, 3/4-in. rotary hammer drill. When used with an optional chipping adapter, the Bosch Rotary Hammer Drill can be used to perform chipping and chiseling tasks such as paint removal from either concrete or metal surfaces. It is ultra-compact, lightweight with an ergonomic balanced grip. The battery operation gives the operator more flexibility during sampling activities.

  19. Biomechanical modelling and evaluation of construction jobs for performance improvement.

    PubMed

    Parida, Ratri; Ray, Pradip Kumar

    2012-01-01

    Occupational risk factors, such as awkward posture, repetition, lack of rest, insufficient illumination and heavy workload related to construction-related MMH activities may cause musculoskeletal disorders and poor performance of the workers, ergonomic design of construction worksystems was a critical need for improving their health and safety wherein a dynamic biomechanical models were required to be empirically developed and tested at a construction site of Tata Steel, the largest steel making company of India in private sector. In this study, a comprehensive framework is proposed for biomechanical evaluation of shovelling and grinding under diverse work environments. The benefit of such an analysis lies in its usefulness in setting guidelines for designing such jobs with minimization of risks of musculoskeletal disorders (MSDs) and enhancing correct methods of carrying out the jobs leading to reduced fatigue and physical stress. Data based on direct observations and videography were collected for the shovellers and grinders over a number of workcycles. Compressive forces and moments for a number of segments and joints are computed with respect to joint flexion and extension. The results indicate that moments and compressive forces at L5/S1 link are significant for shovellers while moments at elbow and wrist are significant for grinders. PMID:22317733

  20. Strip-tillage: A conservation alternative to full-width tillage systems

    NASA Astrophysics Data System (ADS)

    Wolkowski, Richard

    2015-04-01

    Historically no-till management has been a challenge for maize production in the Midwestern USA because crop residue slows the warming of the soil in the spring and can physically impair planting by plugging the planter. After trying no-till, producers often return to more aggressive tillage operations to address residue concerns; however these systems can cause soil erosion and can increase the cost of production. An alternative system known as strip-tillage has been suggested as a compromise between no-till and full-width tillage. This practice utilizes implements that loosen the soil and allow warming in the row area, yet maintain nearly as much residue as no-till. Strip-tillage is generally understood to be a single pass with a separate implement in the fall, although spring strip-tillage is possible if soil moisture and conditions permit. Strip-tillage can be accomplished in a shorter time, with lower energy and equipment inputs compared to full-width tillage. The first of two studies that examined the merits of strip-tillage was conducted the University of Wisconsin Lancaster Agricultural Research Station (42.84, -90.80). Natural runoff collectors were installed in a field having a silt loam soil with an 8% slope in fall chisel and fall strip-tillage system. The measured soil loss in a year that experienced substantial rainfall prior to canopy closure was 10.6 Mg ha-1 in chisel vs. 0.64 Mg ha-1 in strip-tillage. Soil loss was much less for both systems in the second year when early season rainfall was minimal. A second, ten year study was conducted at the University of Wisconsin Arlington Agricultural Research Station (43.30, -89.36) that compared fall strip-tillage with fall chisel/spring field cultivator and no-till systems in both a continuous maize and soybean-maize rotation. This work showed equal maize grain yield in maize after soybean when comparing chisel and strip-tillage. No-till yield was about 5 % lower. Yield in continuous maize was highest in

  1. Theme: Educational Trends.

    ERIC Educational Resources Information Center

    Agricultural Education Magazine, 1998

    1998-01-01

    Includes "Agricultural Education & School-to-Work" (Larson, Cox); Agricultural Opportunities with Home Schoolers" (Frick, Brennan); "Private Schools and Agricultural Education in North Carolina" (Forrest); "Career Pathways" (Sigar, Thompson); "Perkins and Plows" (Lovejoy); "Charter Schools" (Knight, Armstrong); "Telling the College Tech. Prep.…

  2. Where does Strip Tillage Fit in Montana and Wyoming Sugarbeet Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugarbeet in Montana and Wyoming is often grown in a two year rotation alternating with spring grains. Normally, a sugarbeet grower will make five or more passes across a field for fertilizer application, disking, plowing or ripping, leveling, mulching and hilling. The high price of diesel fuel is m...

  3. America's First Government Documentary Films as Teaching Tools.

    ERIC Educational Resources Information Center

    Hendrickson, Kenneth E.

    1991-01-01

    Reviews two documentaries produced by the U.S. government: "The Plow That Broke the Plains" (1936) and "The River" (1937). The first examines soil erosion in the Great Plains; the second considers Mississippi River usage. Narrates storylines and explains initial film criticism. Highlights the films' effectiveness for teaching about the New Deal…

  4. Two Centuries of Soil Conservation.

    ERIC Educational Resources Information Center

    Helms, Douglas

    1991-01-01

    Narrates U.S. soil conservation history since the late eighteenth century. Discusses early practices such as contour plowing. Profiles individuals who promoted soil conservation and were largely responsible for the creation of the Soil Conservation Service. Explains the causes of erosion and how soil conservation districts help farmers prevent…

  5. SOIL-PROFILE ORGANIC CARBON AND TOTAL NITROGEN UNDER BERMUDAGRASS MANAGEMENT IN THE SOUTHERN PIEDMONT USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estimates of potential carbon (C) and nitrogen (N) sequestration at depths below the traditional plow layer (0-30 cm) are limited, but are needed to improve our understanding of management influences on greenhouse gas emissions and nutrient cycling. Soil samples were collected under `Coastal' bermud...

  6. Amazing Grazing.

    ERIC Educational Resources Information Center

    Peterson, Cris

    Countless acres of grasslands stretch across the American West. Centuries ago, bison roamed the range freely and lived off the grass. By the 19th century, herds of cattle grazed the same land. Over time, much of the original grassland was either plowed and planted or trampled to dust, causing the topsoil to dry up and blow away. Today many…

  7. Dilemmas in Introducing Applied Technology: The Plough and the Cattlelords in Timor.

    ERIC Educational Resources Information Center

    Johnston, Mary

    1990-01-01

    An effort to introduce the plow to Timor farmers faced following barriers: nature of the land and climate, strongly demarcated traditional system, tensions among ethnic groups, cattlelords system, necessary time to place/retain trainers in villages. Positive factors were concrete results, use of small groups and native trainers, age of adopters,…

  8. At Paul Quinn, Students Till the Soil to Cultivate a Better College

    ERIC Educational Resources Information Center

    Kelderman, Eric

    2012-01-01

    In autumn, most colleges' football fields are covered with a thick carpet of grass or artificial turf and are adorned with yard lines. But the football field at Paul Quinn College was carved up by plowing and planting. This past fall, portions of the college's gridiron were covered with sweet potatoes, watermelons, peppers, rosemary, and sugar…

  9. Nitrogen, Tillage, and Crop Rotation Effects On Carbon Dioxide and Methane Fluxes from Irrigated Cropping Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Long-term effects of tillage intensity, N fertilization, and crop rotation on carbon dioxide (CO2) and methane (CH4) flux from semiarid irrigated soils are poorly understood. We evaluated effects of: a) tillage intensity [no-till (NT) and moldboard plow tillage (CT)] in a continuous corn rotation; b...

  10. Effect of green manure on E. coli O157:H7 survival in soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Green manure is the remnants of crops (stems, outer leaves, tops of leaves, etc.) that remain in the field after harvest, and are plowed back into the field to increase fertility. The role of green manure in the survival of E. coli O157:H7 in soil has not been examined. We evaluated three types of g...

  11. Devens 2008 Monitoring Update

    EPA Science Inventory

    This document presents results from site monitoring activities during calendar year 2008 at the EPA/ORD Red Cove Study Area relative to site characterization activities under Operable Units 01 (Shepley's Hill Landfill) and 11 (Plow Shop Pond) at the Fort Devens Superfund site. T...

  12. Retirement Straight Talk: The Self-Discovery that It's Not a Simple Transition but a New Phase in Life

    ERIC Educational Resources Information Center

    Draayer, Donald R.

    2004-01-01

    After 38 years as a teacher and school administrator, including 24 years as the superintendent in Minnetonka, Minnesota, Donald Draayer, the author of this article, has discovered that retirement is not one transition, but many, affecting all aspects of life. He is finding that retirement is like virgin soil. The ground must be cleared, plowed and…

  13. Types of Carbon Compounds That Accumulate Under No-Tillage In Rice-Based Rotations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In a long-term field experiment of rice-based rotations near Stuttgart, AR, no-tillage promoted carbon and nitrogen sequestration in the plow layer compared to conventional tillage. The increased amounts of carbon and nitrogen sequestered with no-tillage varied by crop rotation, ranging from about 1...

  14. [Short-term effects of different tillage modes combined with straw-returning on the soil labile organic carbon components in a farmland with rice-wheat double cropping].

    PubMed

    Yang, Min-Fang; Zhu, Li-Qun; Han, Xin-Zhong; Gu, Ke-Jun; Hu, Nai-Juan; Bian, Xin-Min

    2013-05-01

    A two-year (2009-2011) field experiment was conducted to study the effects of different tillage modes, straw-returning, and their interactions on the soil total organic carbon (TOC) and labile organic carbon (LOC) components (easily oxidizable organic carbon (EOC), water-soluble organic carbon (WSOC), and microbial biomass carbon (MBC)) at the soil depths of 0-7, 7-14, and 14-21 cm in a farmland with rice-wheat double cropping. In all treatments of straw-returning, the TOC and LOC contents in each soil layer were significantly higher than those without straw-returning. Under plowing tillage, the MBC content in 0-7 cm soil layer was significantly higher than that under rotary tillage, but the EOC content was in adverse. Rotary tillage made the TOC content in 7 - 14 cm soil layer being significantly higher, as compared with plowing tillage. The TOC, WSOC, and MBC contents in 14-21 cm soil layer under plowing tillage were significantly higher than those under rotary tillage. Plowing tillage combined with rice and wheat straws-returning made the soil TOC content being higher than the other treatments. PMID:24015560

  15. Effect of conservation practices on soil carbon and nitrogen accretion and crop yield in a corn production system in the southeastern coastal plain, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We implemented conservation farming practices (winter cover cropping plus strip tillage) for a non-irrigated corn production system in the southern coastal plain of Georgia, USA that had been previously been managed under a plow and harrow tillage regime. Total soil carbon and nitrogen were measure...

  16. Effect of deep vs. shallow tillage on onion stunting and onion bulb yield, 2012

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A field experiment was conducted at a site inoculated with R. solani AG 8 at the Oregon State University Hermiston Agricultural Research and Extension Center in Hermiston, OR to determine the effect of plowing (deep tillage) vs. rototilling (shallow tillage) on onion stunting caused by R. solani AG ...

  17. Trends and patterns of anthropogenic evolution of chernozems in lands of agricultural afforestation within the territory of forest-steppe in the center of eastern Europe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The anthropogenic evolution of chernozems as a result of plowing and the creation of forest shelterbelts on three meadow-steppe areas of forest-steppe were studied. It was established, that in all areas there are similar patterns, caused by the transformation of virgin soils into arable soils and vi...

  18. Ephemeral Gullies: To Till or Not to Till?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ephemeral gully erosion is now recognized as a significant, if not dominant source of sediment from agricultural lands worldwide. Ephemeral gullies are typically plowed in and tilled across annually or more frequently, thus restoring the original swale and allowing erosion processes to become reacti...

  19. Managing Intensively Grazed Pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage production during periods of summer drought can be increased by including additional species in the pasture mixture, especially if those species have desirable attributes such as improved water use efficiency or deep root systems. Conversion of plowed fields to pasture also has the potential ...

  20. Changing Agricultural Education to Meet Needs of Emerging Careers

    ERIC Educational Resources Information Center

    Parker, Rick; Brase, Terry; Dewsnup, Mel; Anderson, Mandi; Collins, Ashley; Klopp, Deborah; Johnson, Brian; Feldmann, Holly

    2009-01-01

    With less than 2% of Americans involved in traditional production agriculture (cows, plows, and sows), agricultural programs at the secondary and postsecondary levels must change to address the workforce of the future. AgrowKnowledge works at the national level to provide tools for changing agriculture, food, and natural resource educational…

  1. Arsenic Fate, Transport And Stability Study: Groundwater, Surface Water, Soil And Sediment Investigation At Fort Devens Superfund Site

    EPA Science Inventory

    A field investigation was conducted to examine the distribution of arsenic in groundwater, surface water, and sediments at the Fort Devens Superfund Site. The study area encompassed a portion of plow Shop Pond (Red Cove), which receives groundwater discharge from the aquifer und...

  2. Arsenic Fate And Transport In Red Cove, Fort Devens

    EPA Science Inventory

    A field investigation was conducted to evaluate the impact of a discharging arsenic plume on sediment contamination in a cove (Red Cove) within Plow Shop Pond adjacent to Shepley's Hill Landfill at the Fort Devens Superfund Site in Massachusetts. Site characterization included a...

  3. REACTIONS OF FUEL NITROGEN COMPOUNDS UNDER CONDITIONS OF INERT PYROLYSIS

    EPA Science Inventory

    The paper describes the pyrolysis of fossil fuels and model nitrogen compounds in helium in a small quartz plow reactor, as part of a study of the chemical mechanisms involved in the conversion of fuel-nitrogen compounds to nitric oxide (NO) during combustion. Hydrogen cyanide (H...

  4. VARIATION OF SURFACE SOIL QUALITY BY INTENSIVE DONKEY-DRAWN TILLAGE ON A STEEP SLOPE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The progressive but relatively rapid redistribution of soil from uplands to field depressions or lower field boundaries by tillage has the potential to modify soil properties. However, few direct measurements have been made for this effect. We conducted 50 plowing operations using a donkey-drawn mol...

  5. Nitrogen fertilizer effects on irrigated conventional tillage corn yields and soil carbon and nitrogen pools

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conventional plow tillage (CT) is a common soil management practice under irrigated continuous corn (Zea mays L.) in the semiarid central Great Plains that requires a relatively high nitrogen (N) fertilizer rate to optimize grain yield and economic returns. This study investigated how four rates of ...

  6. The Navajo Agricultural Projects Industry: Subsistence Farming to Corporate Agribusiness.

    ERIC Educational Resources Information Center

    Barry, Tom

    1979-01-01

    Originally designed to create small farms for individual Navajos, the irrigation project has grown into a single 110,000-acre corporate agribusiness, the land's management has fallen out of the grasp of individual Navajos, and the idea of subsistence farming has been plowed under for the planting of major money-making crops. (NQ)

  7. 43. From Superintendent's Monthly Report, March 1936. Haleakala District Ranger ...

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

    43. From Superintendent's Monthly Report, March 1936. Haleakala District Ranger J.A. Peck, Photographer. THIS IS HAWAII-CLEARING SNOW FROM HALEAKALA ROAD AFTER STORM. HOWEVER THIS IS NOT A PRELIMINARY JUSTIFICATION FOR THE PURCHASE OF ROTARY PLOW. PHOTO PECK, FEB. 5. - Haleakala National Park Roads, Pukalani, Maui County, HI

  8. Long-term tillage impacts on soil aggregation and carbon dynamics under wheat-fallow in the central Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conventional tillage (CT) winter wheat (Tritucum aestivum L.) with summer fallow (WF) is the predominant cropping system in the central Great Plains. We investigated the effect of 39 yr of different tillage intensities, conventional tillage (CT); moldboard plow (MP); no-tillage (NT); and reduced ti...

  9. Challenges and Strategies Related to Hearing Loss among Dairy Farmers

    ERIC Educational Resources Information Center

    Hass-Slavin, Louise; McColl, Mary Ann; Pickett, William

    2005-01-01

    Context: Farming is often imagined to be a serene and idyllic business based on historical images of a man, a horse, and a plow. However, machinery and equipment on farms, such as older tractors, grain dryers, and vacuum pumps, can have noise levels, which may be dangerous to hearing with prolonged, unprotected exposure. Purpose: This qualitative…

  10. ARSENIC TRANSPORT ACROSS THE GROUNDWATER – SURFACE WATER INTERFACE AT A SITE IN CENTRAL MASSACHUSETTS

    EPA Science Inventory

    Plow Shop Pond, located in central Massachusetts within the New England ‘arsenic belt,’ receives water from a series of interconnected upstream ponds as well as from upward-discharging groundwater. A small, shallow embayment on the southwest side of the pond is known as Red Cove...

  11. Nudging toward Inquiry: Awakening and Building upon Prior Knowledge

    ERIC Educational Resources Information Center

    Fontichiaro, Kristin, Comp.

    2010-01-01

    "Prior knowledge" (sometimes called schema or background knowledge) is information one already knows that helps him/her make sense of new information. New learning builds on existing prior knowledge. In traditional reporting-style research projects, students bypass this crucial step and plow right into answer-finding. It's no wonder that many…

  12. Carbon monoxide fluxes from natural, managed, or cultivated savannah grasslands

    NASA Astrophysics Data System (ADS)

    Sanhueza, Eugenio; Donoso, Loreto; Scharffe, Dieter; Crutzen, Paul J.

    1994-08-01

    As part of a comprehensive study on tropical land use change and its effect on atmospheric trace gas fluxes, we report the CO fluxes recorded at a natural grassland site and the changes produced when this ecosystem was managed or cultivated. The field site is located in the central part of the savannah climatic region of Venezuela. Fluxes were measured in the dark using the enclosed chamber technique. CO was analyzed with a reduction-gas detector in combination with a molecular sieve 5A columm for CO separation. At all sites, CO fluxes exhibited a strong diurnal variation, with net emission during daytime and consumption or no fluxes during nightime. In unplowed soils no differences were observed between dry and rainy season. A large disparity was observed between unplowed and plowed grassland soils. Plowed soil shows a much smaller emission during daytime and a larger consumption at night. The 24-hour integrated fluxes indicate that the nonperturbed grassland switches from being a net source of CO (3.4×1010 molecules cm-2 s-1) to being a net sink (-1.6×1010 molecules cm-2s-1) after plowing. It is likely that burial of surface litter reduces the production of CO in the top soil and that the diffusion of CO to deeper layers (where CO is consumed by microbiological processes) is promoted in decompacted soils. As the rainy season progressed the plowed soil gradually compacted and CO fluxes changed back, and after 3 months the fluxes from plowed soils and the original unplowed soils were equal. Even though the various cultivated fields (corn, sorghum, and pasture) received differing inorganic fertilization treatments, no significant difference in the CO fluxes resulted. Measurements during the dry season suggest that "degrading dry (dead) vegetation" produces CO under dark conditions.

  13. Carbon monoxide fluxes from natural, managed, or cultivated savannah grasslands

    SciTech Connect

    Sanhueza, E.; Donoso, L.; Scharffe, D.; Crutzen, P.J.

    1994-08-20

    As part of a comprehensive study on tropical land use change and its effect on atmospheric trace gas fluxes, we report the CO fluxes recorded at a natural grassland site and the changes produced when this ecosystem was managed or cultivated. The field site is located in the central part of the savannah climatic region of Venezuela. Fluxes were measured in the dark using the enclosed chamber technique. CO was analyzed with a reduction-gas detector in combination with a molecular sieve 5A column for CO separation. At all sites, CO fluxes exhibited a strong diurnal variation, with net emission during daytime and consumption or no fluxes during nighttime. In unplowed soils no differences were observed between dry and rainy season. A large disparity was observed between unplowed and plowed grassland soils. Plowed soil shows a much smaller emission during daytime and a larger consumption at night. The 24-hour integrated fluxes indicate that the nonperturbed grassland switches from being a net source of CO (3.4 x 10{sup 10} molecules cm{sup {minus}2} s{sup {minus}1}) to being a net sink (-1.6 x 10{sup 10} molecules cm{sup {minus}2} s{sup {minus}1}) after plowing. It is likely that burial of surface litter reduces the production of CO in the top soil and that the diffusion of CO to deeper layers (where CO is consumed by microbiological processes) is promoted in decompacted soils. As the rainy season progressed the plowed soil gradually compacted and CO fluxes changed back, and after 3 months the fluxes from plowed soils and the original unplowed soils were equal. Even though the various cultivated fields (corn, sorghum, and pasture) received differing inorganic fertilization treatments, no significant difference in the CO fluxes resulted. Measurements during the dry season suggest that {open_quotes}degrading dry (dead) vegetation{close_quotes} produces CO under dark conditions. 14 refs., 5 figs., 3 tabs.

  14. Factors associated with duck nest success in the prairie pothole region of Canada

    USGS Publications Warehouse

    Greenwood, R.J.; Sargeant, A.B.; Johnson, D.H.; Cowardin, L.; Shaffer, T.L.

    1995-01-01

    Populations of some dabbling ducks have declined sharply in recent decades and information is needed to understand reasons for this. During 1982-85, we studied duck nesting for 1-4 years in 17 1.6 by 16.0-km, high-density duck areas in the Prairie Pothole Region (PPR) of Canada, 9 in parkland and 8 in prairie. We estimated nest-initiation dates, habitat preferences, nest success, and nest fates for mallards (Anas platyrhynchos), gadwalls (A. strepera), blue-winged teals (A. discors), northern shovelers (A. clypeata), and northern pintails (A. acuta). We also examined the relation of mallard production to geographic and temporal variation in wetlands, breeding populations, nesting effort, and hatch rate.Average periods of nest initiation were similar for mallards and northern pintails, and nearly twice as long as those of gadwalls, blue-winged teals, and northern shovelers. Median date of nest initiation was related to presence of wet wetlands (contained visible standing water), spring precipitation, and May temperature. Length of initiation period was related to presence of wet wetlands and precipitation in May, June temperature, and nest success; it was negatively related overall to drought that prevailed over much of Prairie Canada during the study, especially in 1984.Mallards, gadwalls, and northern pintails nested most often in brush in native grassland, blue-winged teals in road rights-of-way, and northern shovelers in hayfields and small (<2 ha) untilled tracts of upland habitat (hereafter called Odd area). Among 8 habitat classes that composed all suitable nesting habitat of each study area, nest success estimates averaged 25% in Woodland, 19% in Brush, 18% in Hayland, 16% in Wetland, 15% in Grass, 11% in Odd area, 8% in Right-of-way, and 2% in Cropland. We detected no significant difference in nest success among species: mallard (11%), gadwall (14%), blue-winged teal (15%), northern shoveler (12%), and northern pintail (7%). Annual nest success (pooled by

  15. Assessment of strip tillage systems for maize production in semi-arid Ethiopia: Effects on grain yield, water balance and water productivity

    NASA Astrophysics Data System (ADS)

    Temesgen, Melesse; Savenije, H. H. G.; Rockström, J.; Hoogmoed, W. B.

    The Maresha, the traditional Ethiopian plow, requires repeated cross-plowing which causes increased surface runoff, less infiltration and hence lower water availability to crops. The main reasons for increased surface runoff and reduced infiltration are plowing along the slope and the formation of a plow pan at shallow depths. Conservation tillage is seen as a way to alleviate these problems. The widely advocated zero-tillage, however, is not feasible for smallholder farmers in semi-arid regions of Ethiopia because of difficulties in maintaining adequate soil cover, the practice of communal grazing, and high costs of herbicides. Strip tillage systems, on the other hand, may offer a solution. This study was initiated to test strip tillage systems and to evaluate the impacts of new tillage systems on the water balance and grain yields of maize. Experiments have been conducted in a semi-arid area called Melkawoba in the central Rift Valley of Ethiopia during 2003-2005. Strip tillage systems involved cultivation along planting lines at a spacing of 0.75 m using the Maresha plow followed by subsoiling along the same lines (STS) or without subsoiling (ST). Results have been compared with traditional tillage involving 3-4 overpasses with the Maresha plow (CONV). Soil moisture has been monitored to a depth of 1.8 m using a Time Domain Reflectometer (TDR) while surface runoff has been measured using a specially designed rectangular trough installed at the bottom of each plot. STS resulted in the least surface runoff (Qs = 18 mm season-1) and the highest grain yields (Y = 2130 kg ha-1) followed by ST (Qs = 26 mm season-1, Y = 1840 kg ha-1) and CONV (Qs = 43 mm season-1, Y = 1720 kg ha-1) provided sowing was carried out within a week after subsoiling. Thus, STS resulted in the highest water productivity, WP = 0.60 kg m-3, followed by ST (WP = 0.52 kg m-3) and CONV (WP = 0.48 kg m-3). The main conclusion of the paper is that even in dry areas reasonable yields can be obtained

  16. Assessment of strip tillage systems for maize production in semi-arid Ethiopia: effects on grain yield and water balance

    NASA Astrophysics Data System (ADS)

    Temesgen, M.; Rockstrom, J.; Savenije, H. H. G.; Hoogmoed, W. B.

    2007-07-01

    The traditional tillage implement, the Maresha plow, and the tillage systems that require repeated and cross plowing have caused poor rainfall partitioning, land degradation and hence low water productivity in Ethiopia. Conservation tillage could alleviate these problems. However, no-till can not be feasible for smallholder farmers in semi-arid regions of Ethiopia because of difficulties in maintaining soil cover due to low rainfall and communal grazing and because of high costs of herbicides. Strip tillage systems may offer a solution. This study was initiated to test strip tillage systems using implements that were modified forms of the Maresha plow, and to evaluate the impacts of the new tillage systems on water balance and grain yields of maize (Zea mays XX). Experiments were conducted in two dry semi arid areas called Melkawoba and Wulinchity, in the central Rift Valley of Ethiopia during 2003-2005. Strip tillage systems that involved cultivating planting lines at a spacing of 0.75 m using the Maresha plow followed by subsoiling along the same lines (STS) and without subsoiling (ST) were compared with the traditional tillage system of 3 to 4 times plowing with the Maresha plow (CONV). Soil moisture was monitored to a depth of 1.8 m using Time Domain Reflectometer while surface runoff was measured using rectangular trough installed at the bottom of each plot. STS resulted in the least surface runoff (Qs=17 mm-season-1), the highest transpiration (T=196 mm-season-1), the highest grain yields (Y=2130 kg-ha-1) and the highest water productivity using total evaporation (WPET=0.67 kg-m-3) followed by ST (Qs=25 mm-season-1, T=178 mm-season-1, Y=1840 kg-ha-1, WPET=0.60 kg-m-3) and CONV (Qs=40 mm-season-1,T=158 mm-season-1, Y=1720 kg-ha-1, WPET=0.58 kg-m-3). However, when the time between the last tillage operation and planting of maize was more than 26 days, the reverse occurred. There was no statistically significant change in soil physical and chemical properties

  17. Selecting Tasks for Evaluating Human Performance as a Function of Gravity

    NASA Technical Reports Server (NTRS)

    Norcross, J. R.; Gernhardt, M. L.

    2010-01-01

    A challenge in understanding human performance as a function of gravity is determining which tasks to research. Initial studies began with treadmill walking, which was easy to quantify and control. However, with the development of pressurized rovers, it is less important to optimize human performance for ambulation as rovers will likely perform gross translation for them. Future crews are likely to spend much of their extravehicular activity (EVA) performing geology, construction and maintenance type tasks, for which it is difficult to measure steady-state-workloads. To evaluate human performance in reduced gravity, we have collected metabolic, biomechanical and subjective data for different tasks at varied gravity levels. Methods: Ten subjects completed 5 different tasks including weight transfer, shoveling, treadmill walking, treadmill running and treadmill incline walking. All tasks were performed shirt-sleeved at 1-g, 3/8-g and 1/6-g. Off-loaded conditions were achieved via the Active Response Gravity Offload System. Treadmill tasks were performed for 3 minutes with reported oxygen consumption (VO2) averaged over the last 2 minutes. Shoveling was performed for 3 minutes with metabolic cost reported as ml O2 consumed per kg material shoveled. Weight transfer reports metabolic cost as liters O2 consumed to complete the task. Statistical analysis was performed via repeated measures ANOVA. Results: Statistically significant metabolic differences were noted between all 3 gravity levels for treadmill running and incline walking. For the other 3 tasks, there were significant differences between 1-g and each reduced gravity, but not between 1/6-g and 3/8-g. For weight transfer, significant differences were seen between gravities in both trial-average VO2 and time-to-completion with noted differences in strategy for task completion. Conclusion: To determine if gravity has a metabolic effect on human performance, this research may indicate that tasks should be selected

  18. LBNL Computational Research and Theory Facility Groundbreaking. February 1st, 2012

    SciTech Connect

    Yelick, Kathy

    2012-01-01

    Energy Secretary Steven Chu, along with Berkeley Lab and UC leaders, broke ground on the Lab's Computational Research and Theory (CRT) facility yesterday. The CRT will be at the forefront of high-performance supercomputing research and be DOE's most efficient facility of its kind. Joining Secretary Chu as speakers were Lab Director Paul Alivisatos, UC President Mark Yudof, Office of Science Director Bill Brinkman, and UC Berkeley Chancellor Robert Birgeneau. The festivities were emceed by Associate Lab Director for Computing Sciences, Kathy Yelick, and Berkeley Mayor Tom Bates joined in the shovel ceremony.

  19. A new species of Triplophysa Rendahl (Cypriniformes, Nemacheilidae) from Sichuan Province, China

    PubMed Central

    YAN, Si-Li; SUN, Zhi-Yu; GUO, Yan-Shu

    2015-01-01

    Triplophysa yajiangensis sp. nov. is described from the upper and middle reaches of the Yalong River, Yangtze Basin, Ganzi Prefecture, Sichuan Province, China. This new species can be distinguished from other congeneric species by the following characters: body surface smooth and scaleless; lateral line complete; caudal peduncle compressed and tapered slightly; lower jaw shovel-shaped; head shorter than caudal peduncle; dorsal-fin origin anterior to pelvic-fin origin and closer to tip of snout than to caudal-fin base, last unbranched ray hard; pelvic-fin reaches or exceeds anus; posterior chamber of gas bladder absent; intestine spiral type with 3-5 winding coils. PMID:26452694

  20. Landslide tsunami hazard in New South Wales, Australia: novel observations from 3D modelling

    NASA Astrophysics Data System (ADS)

    Power, Hannah; Clarke, Samantha; Hubble, Tom

    2015-04-01

    This paper examines the potential of tsunami inundation generated from two case study sites of submarine mass failures on the New South Wales coast of Australia. Two submarine mass failure events are investigated: the Bulli Slide and the Shovel Slide. Both slides are located approximately 65 km southeast of Sydney and 60 km east of the township of Wollongong. The Bulli Slide (~20 km3) and the Shovel Slide (7.97 km3) correspond to the two largest identified erosional surface submarine landslides scars of the NSW continental margin (Glenn et al. 2008; Clarke 2014) and represent examples of large to very large submarine landslide scars. The Shovel Slide is a moderately thick (80-165 m), moderately wide to wide (4.4 km) slide, and is located in 880 m water depth; and the Bulli Slide is an extremely thick (200-425 m), very wide (8.9 km) slide, and is located in 1500 m water depth. Previous work on the east Australian margin (Clarke et al., 2014) and elsewhere (Harbitz et al., 2013) suggests that submarine landslides similar to the Bulli Slide or the Shovel Slide are volumetrically large enough and occur at shallow enough water depths (400-2500 m) to generate substantial tsunamis that could cause widespread damage on the east Australian coast and threaten coastal communities (Burbidge et al. 2008; Clarke 2014; Talukder and Volker 2014). Currently, the tsunamogenic potential of these two slides has only been investigated using 2D modelling (Clarke 2014) and to date it has been difficult to establish the onshore tsunami surge characteristics for the submarine landslides with certainty. To address this knowledge gap, the forecast inundation as a result of these two mass failure events was investigated using a three-dimensional model (ANUGA) that predicts water flow resulting from natural hazard events such as tsunami (Nielsen et al., 2005). The ANUGA model solves the two-dimensional shallow water wave equations and accurately models the process of wetting and drying thus

  1. LBNL Computational Research & Theory Facility Groundbreaking - Full Press Conference. Feb 1st, 2012

    ScienceCinema

    Yelick, Kathy

    2013-05-29

    Energy Secretary Steven Chu, along with Berkeley Lab and UC leaders, broke ground on the Lab's Computational Research and Theory (CRT) facility yesterday. The CRT will be at the forefront of high-performance supercomputing research and be DOE's most efficient facility of its kind. Joining Secretary Chu as speakers were Lab Director Paul Alivisatos, UC President Mark Yudof, Office of Science Director Bill Brinkman, and UC Berkeley Chancellor Robert Birgeneau. The festivities were emceed by Associate Lab Director for Computing Sciences, Kathy Yelick, and Berkeley Mayor Tom Bates joined in the shovel ceremony.

  2. LBNL Computational Research & Theory Facility Groundbreaking - Full Press Conference. Feb 1st, 2012

    SciTech Connect

    Yelick, Kathy

    2012-01-01

    Energy Secretary Steven Chu, along with Berkeley Lab and UC leaders, broke ground on the Lab's Computational Research and Theory (CRT) facility yesterday. The CRT will be at the forefront of high-performance supercomputing research and be DOE's most efficient facility of its kind. Joining Secretary Chu as speakers were Lab Director Paul Alivisatos, UC President Mark Yudof, Office of Science Director Bill Brinkman, and UC Berkeley Chancellor Robert Birgeneau. The festivities were emceed by Associate Lab Director for Computing Sciences, Kathy Yelick, and Berkeley Mayor Tom Bates joined in the shovel ceremony.

  3. A new species of Triplophysa Rendahl (Cypriniformes, Nemacheilidae) from Sichuan Province, China.

    PubMed

    Yan, Si-Li; Sun, Zhi-Yu; Guo, Yan-Shu

    2015-09-18

    Triplophysa yajiangensis sp. nov. is described from the upper and middle reaches of the Yalong River, Yangtze Basin, Ganzi Prefecture, Sichuan Province, China. This new species can be distinguished from other congeneric species by the following characters: body surface smooth and scaleless; lateral line complete; caudal peduncle compressed and tapered slightly; lower jaw shovel-shaped; head shorter than caudal peduncle; dorsal-fin origin anterior to pelvic-fin origin and closer to tip of snout than to caudal-fin base, last unbranched ray hard; pelvic-fin reaches or exceeds anus; posterior chamber of gas bladder absent; intestine spiral type with 3-5 winding coils. PMID:26452694

  4. LBNL Computational Research and Theory Facility Groundbreaking. February 1st, 2012

    ScienceCinema

    Yelick, Kathy

    2013-05-29

    Energy Secretary Steven Chu, along with Berkeley Lab and UC leaders, broke ground on the Lab's Computational Research and Theory (CRT) facility yesterday. The CRT will be at the forefront of high-performance supercomputing research and be DOE's most efficient facility of its kind. Joining Secretary Chu as speakers were Lab Director Paul Alivisatos, UC President Mark Yudof, Office of Science Director Bill Brinkman, and UC Berkeley Chancellor Robert Birgeneau. The festivities were emceed by Associate Lab Director for Computing Sciences, Kathy Yelick, and Berkeley Mayor Tom Bates joined in the shovel ceremony.

  5. Conveyor system moves material continuously

    SciTech Connect

    Not Available

    1983-12-01

    German technology and equipment is used in mining operations worldwide. A PHB Wesserhutte system is being used with face shovel, mobile crusher, crawler-mounted transfer conveyor, and shiftable conveyor which results in crushing and transporting the minerals to the processing plant in a continuous flow path. The entire process is controlled by a programmable logic controller (a mini-computer) and all systems are sequentially interlocked according to the material flow path. Working methods using the mobile crusher and conveying systems are illustrated.

  6. NASA Shared Services Center breaks ground

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA officials and elected leaders were on hand for the groundbreaking ceremony of the NASA Shared Services Center Feb. 24, 2006, on the grounds of Stennis Space Center. The NSSC provides agency centralized administrative processing, human resources, procurement and financial services. From left, Louisiana Economic Development Secretary Mike Olivier, Stennis Space Center Director Rick Gilbrech, Computer Sciences Corp. President Michael Laphen, NASA Deputy Administrator Shana Dale, Rep. Gene Taylor, Sen. Trent Lott, Mississippi Gov. Haley Barbour, NASA Administrator Mike Griffin and Shared Services Center Executive Director Arbuthnot use golden shovels to break ground at the site.

  7. Some Factors Causing Variability in 1,2-Dibromo-3-Chloropropane Concentrations in Soil

    PubMed Central

    McKenry, M. V.; Naylor, P.

    1979-01-01

    Relative to nematicides with greater fuming capabilities, 1,2-dibromo-3-chloropropane (DBCP) moved nonuniformly through soil. DBCP concentrations in soil were reduced by low soil temperature and the presence of lime or roots within the soil profile, Applications by either water or chisel injection provided DBCP movement to 120 cm and below. Concentrations were least persistent in the upper 15 cm of the field surface and in one situation where application was not followed by irrigation. Values for Henry's Constant are reported for DBCP at a range of solution temperatures. Certain advantages and disadvantages of soil atmosphere sampling of DBCP are discussed. PMID:19300644

  8. Ultrasonic/Sonic Jackhammer

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Sherrit, Stewart; Herz, Jack

    2005-01-01

    An ultrasonic/sonic jackhammer (USJ) is the latest in a series of related devices. Each of these devices cuts into a brittle material by means of hammering and chiseling actions of a tool bit excited with a combination of ultrasonic and sonic vibrations. A small-scale prototype of the USJ has been demonstrated. A fully developed, full-scale version of the USJ would be used for cutting through concrete, rocks, hard asphalt, and other materials to which conventional pneumatic jackhammers are applied, but the USJ would offer several advantages over conventional pneumatic jackhammers.

  9. Technology and methods of making decorated balusters

    NASA Astrophysics Data System (ADS)

    Krauinsh, D.; Selivanova, A.

    2015-10-01

    Woodworking companies looking for a simple solution to simplify and speed up the whole process of making a carved balusters. Tech solution is the replacement of threaded elements solid wood balusters on plastic threaded overhead items secured by adhesive to the surface of the workpiece chiseled. This solution allows to reduce the cost of manufacturing carved balusters, without resorting to a woodcarver and using expensive equipment. Through further improvements, such as painting, patina, it turns out a product that is difficult to distinguish from solid carved balusters.

  10. Modified lingual split technique for extraction of impacted mandibular third molars.

    PubMed

    Lewis, J E

    1980-08-01

    Critical evaluation of existing chisel and bur techniques for removal of impacted mandibular third molars reveals a high incidence of complications. Both approaches require creation of a buccal defect immediately distal to the second molar for the insertion of an elevator, which may cause pocketing to occur postoperatively. The method described here minimizes periosteal reflection, almost completely avoids loss of bone, and effectively reduces the use of rotary instrumentation. The planning of the soft tissue flaps and bony cuts assists in primary wound closure, obliteration of dead space, and reduction of postoperative morbidity. PMID:6930459

  11. Friction and wear behavior of single-crystal silicon carbide in contact with titanium

    NASA Technical Reports Server (NTRS)

    Miyoshi, K.; Buckley, D. H.

    1977-01-01

    Sliding friction experiments were conducted with single crystal silicon carbide in sliding contact with titanium. Results indicate that the friction coefficient is greater in vacuum than in argon and that this is due to the greater adhesion or adhesive transfer in vacuum. Thin films of silicon carbide transferred to titanium also adhered to silicon carbide both in argon at atmospheric pressure and in high vacuum. Cohesive bonds fractured on both the silicon carbide and titanium surfaces. The wear debris of silicon carbide created by fracture plowed the silicon carbide surface in a plastic manner. The friction characteristics of titanium in contact with silicon carbide were sensitive to the surface roughness of silicon carbide, and the friction coefficients were higher for a rough surface of silicon carbide than for a smooth one. The difference in friction results was due to plastic deformation (plowing of titanium).

  12. Scattering of electromagnetic waves from a randomly perturbed quasiperiodic surface

    NASA Technical Reports Server (NTRS)

    Shin, R. T.; Kong, J. A.

    1984-01-01

    Electromagnetic-wave scattering by a quasi-periodic surface with random perturbations (as in the remote sensing of plowed fields) is investigated analytically, applying the Kirchhoff approximation and modeling the plowed fields by means of Gaussian random variation, sinusoidal variation, and Gaussian random variation about the spatial frequency. Coherent and incoherent bistatic scattering coefficients are derived in closed form by evaluating the physical-optics integral and shown to be proportional, in the geometric-optics limit, to the occurrence probability of slopes which reflect the incident wave specularly in the direction of the scattered wave. Backscattering cross sections are plotted as functions of incidence angle for a number of cases, demonstrating the strong effect of row direction.

  13. Habitat use by Swainson's Hawks on their austral winter grounds in Argentina

    USGS Publications Warehouse

    Canavelli, Sonia B.; Bechard, Marc J.; Woodbridge, B.; Kochert, Michael N.; Maceda, Juan J.; Zaccagnini, Maria E.

    2003-01-01

    We examined the use of agricultural habitats by Swainson's Hawks (Buteo swainsoni)in La Pampa and Santa Fe provinces, Argentina. We found an association of foraging Swainson's Hawks with permanent pastures such as fallow, natural, and alfalfa fields. The hawks also used plowed fields for sunning, resting, and preening. Fields planted with annual crops and pastures were used very little, except when they were cut for hay, plowed, and harvested, or when low crop height and cover allowed the hawks to land in fields. The availability of abundant, yet widely-spaced and transient food-sources, such as insect outbreaks, appeared to be the principal factor influencing habitat use by the hawks. Their reliance on agricultural habitats makes Swainson's Hawks highly vulnerable to pesticide contamination and has contributed to the occurrence of significant mortality events on their wintering grounds.

  14. Swarm Verification

    NASA Technical Reports Server (NTRS)

    Holzmann, Gerard J.; Joshi, Rajeev; Groce, Alex

    2008-01-01

    Reportedly, supercomputer designer Seymour Cray once said that he would sooner use two strong oxen to plow a field than a thousand chickens. Although this is undoubtedly wise when it comes to plowing a field, it is not so clear for other types of tasks. Model checking problems are of the proverbial "search the needle in a haystack" type. Such problems can often be parallelized easily. Alas, none of the usual divide and conquer methods can be used to parallelize the working of a model checker. Given that it has become easier than ever to gain access to large numbers of computers to perform even routine tasks it is becoming more and more attractive to find alternate ways to use these resources to speed up model checking tasks. This paper describes one such method, called swarm verification.

  15. The influence of complex compost on the aggregate composition and water and air properties of an ordinary chernozem

    NASA Astrophysics Data System (ADS)

    Belyuchenko, I. S.; Antonenko, D. A.

    2015-07-01

    The influence of complex compost composed of the waste products of the agriculture (semi-rotted cattle manure and plant residues) and chemical industries (phosphogypsum) on the agrophysical properties of an ordinary chernozem (Haplic Chernozem) was studied in the western Ciscaucasian region. In the field experiment, the compost was applied to the plow layer (0-20 cm) in 2007. In five years, the content of agronomically valuable aggregates increased by 7-9%, and their water stability became higher. This resulted in a better aggregation of the plow layer; its bulk density decreased by about 0.1 g/cm3 in comparison with the control plot treated with mineral fertilizers according to traditional technology. The water and air properties of the soil were optimized, which was seen from an increase in the field and total water capacity, total porosity, and soil water storage.

  16. Changes in the properties of solonetzic soil complexes in the dry steppe zone under anthropogenic impacts

    NASA Astrophysics Data System (ADS)

    Lyubimova, I. N.; Novikova, A. F.

    2016-05-01

    Long-term studies of changes in the properties of solonetzic soil complexes of the dry steppe zone under anthropogenic impacts (deep plowing, surface leveling, irrigation, and post-irrigation use) have been performed on the Privolzhskaya sand ridge and the Khvalyn and Ergeni plains. The natural morphology of solonetzic soils was strongly disturbed during their deep ameliorative plowing. At present, the soil cover consists of solonetzic agrozems (Sodic Protosalic Cambisols (Loamic, Aric, Protocalcic)), textural (clay-illuvial) calcareous agrozems (Eutric Cambisols (Loamic, Aric, Protocalcic)), agrosolonetzes (Endocalcaric Luvisols (Loamic, Aric, Cutanic, Protosodic), agrochestnut soils (Eutric Cambisols (Siltic, Aric)), and meadowchestnut soils (Haplic Kastanozems). No features attesting to the restoration of the initial profile of solonetzes have been found. The dynamics of soluble salts and exchangeable sodium differ in the agrosolonetzes and solonetzic agrozems. A rise in pH values takes place in the middle part of the soil profiles on the Khvalyn and Ergeni plains.

  17. ERIP invention 637. Technical progress report 2nd quarter, April 1997--June 1997

    SciTech Connect

    Thacker, G.W.

    1997-07-22

    This technical report describes progress in the development of the Pegasus plow, a stalk and root embedding apparatus. Prototype testing is reported, and includes the addition of precision tillage. Disease data, organic matter, and nitrogen levels results are very briefly described. Progress in marketing is also reported. Current marketing issues include test use by cotton and wheat growers, establishment of dealer relationships, incorporation of design modifications, expansion of marketing activities, and expansion of loan and lease program.

  18. Extractable trace elements in the soil profile after years of biosolids application

    SciTech Connect

    Barbarick, K.A.; Ippolito, J.A.; Westfall, D.G.

    1998-07-01

    The US Environmental Protection Agency (USEPA) and some state agencies regulate trace element additions to soil from land application of biosolids. The authors generally consider trace elements added in biosolids (sewage sludge) to accumulate in the soil surface without significant transport below the plow layer. They used 11 yr of field-study information from biosolids addition to dryland hard red winter wheat (Triticum aestivum L. Vona or TAM107) to determine the distribution of NH{sub 4}HCO{sub 3} diethylenetriaminepentaacetic acid (AB-DTPA)-extractable Cd, Cr, Cu, Mo, Ni, Pb, and Zn in 0 to 20 (plow layer), 20 to 60, 60 to 100, and 100 to 150 cm depth increments. This study is unique since it involves multiple biosolids application in a dryland summer fallow agroecosystem. The authors applied five or six applications of biosolids from the cities of Littleton and Englewood, CO, to Weld loam or Platner loam at four locations. This paper focuses on the 0 (control), the 56 or 67 kg of N ha{sup {minus}1} fertilizer rates, and the 6.7 and 26.8 dry Mg of biosolids ha{sup {minus}1} rates that they added every crop year. The authors observed significant (P < 0.10) accumulations of the trace elements in the plow layer of the biosolids-amended soils. Only Zn showed consistent increases in extractable levels below the plow layer at all four sites. The biosolids Zn concentration was larger than any other trace element resulting in larger loading of this element.

  19. Evaluation of remote sensing in control of pink bollworm in cotton

    NASA Technical Reports Server (NTRS)

    Coleman, V. B.; Johnson, C. W.; Lewis, L. N.

    1973-01-01

    The use of satellite data from the ERTS-1 satellite for mapping the cotton acreage in the southern deserts of California is discussed. The differences between a growing, a defoliated, and a plowed down field can be identified using an optical color combiner. The specific application of the land use maps is to control the spread of the pink bollworms by establishing planting and plowdown dates.

  20. Waiting for Water

    ERIC Educational Resources Information Center

    Lamson-Nussbaum, Jorie

    2013-01-01

    The author waits in the hot and oppressive air while dust devils are born and die over the newly plowed field. It is a dry spring and she prays for rain. The lupine beans withered to dry threads last week and the corn that sprouted in a green haze over the north field is turning to brown paper. However, driving north, the author discovers the Rum…

  1. Surface Roughness Parameter Uncertainties on Radar Based Soil Moisture Retrievals

    NASA Technical Reports Server (NTRS)

    Joseph, A. T.; vanderVelde, R.; O'Neill, P. E.; Lang, R.; Su, Z.; Gish, T.

    2012-01-01

    Surface roughness variations are often assumed to be negligible for the retrieval of sol moisture. Although previous investigations have suggested that this assumption is reasonable for natural vegetation covers (i.e. Moran et al. 2002), in-situ measurements over plowed agricultural fields (i.e. Callens et al. 2006) have shown that the soil surface roughness can change considerably due to weathering induced by rain.

  2. [Effect of tillage patterns on the structure of weed communities in oat fields in the cold and arid region of North China].

    PubMed

    Zhang, Li; Zhang, Li; Wu, Dong-Xia; Zhang, Jun-Jun

    2014-06-01

    In order to clarify the effects of tillage patterns on farmland weed community structure and crop production characteristics, based on 10 years location experiment with no-tillage, subsoiling and conventional tillage in the cold and arid region of North China, and supplementary experiment of plowing after 10 years no-tillage and subsoiling, oat was planted in 2 soils under different tillage patterns, and field weed total density, dominant weed types, weed diversity index, field weed biomass and oats yield were measured. The results showed that the regional weed community was dominated by foxtail weed (Setaira viridis); the weed density under long-term no-tillage was 2.20-5.14 times of tillage at different growing stages of oat, but there were no significant differences between conditional tillage and plowing after long-term no-tillage and subsoiling. Field weed Shannon diversity indices were 0.429 and 0.531, respectively, for sandy chestnut soil and loamy meadow soil under no-tillage conditions, and field weed biomass values were 1.35 and 2.26 times of plowing treatment, while the oat biomass values were only 2807.4 kg x hm(-2) and 4053.9 kg x hm(-2), decreased by 22.3% and 46.2%, respectively. The results showed that the weed community characteristics were affected by both tillage patterns and soil types. Long-term no-tillage farmland in the cold and arid region of North China could promote the natural evolution of plant communities by keeping more perennial weeds, and the plowing pattern lowered the annual weed density, eliminated perennial weeds with shallow roots, and stimulated perennial weeds with deep roots. PMID:25223030

  3. Horses--Haulers, Racers, and Healers

    ERIC Educational Resources Information Center

    McIntosh, Phyllis

    2014-01-01

    Providing healing support for everyone from an autistic child to a wounded veteran is just the latest addition to the horse's 5,000-year-old résumé. No animal has played a greater role in human history. Horses have carried us into war, pulled our loads, plowed our fields, and transported us over all kinds of terrain. Freed of such drudgery by…

  4. AmeriFlux US-Ne1 Mead - irrigated continuous maize site

    DOE Data Explorer

    Suyker, Andy [University of Nebraska - Lincoln

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ne1 Mead - irrigated continuous maize site. Site Description - The study site is one of three fields (all located within 1.6 km of each other) at the University of Nebraska Agricultural Research and Development Center near Mead, Nebraska. This site is irrigated with a center pivot system. Prior to the initiation of the study, the irrigated site had a 10-yr history of maize-soybean rotation under no-till. A tillage operation (disking) was done just prior to the 2001 planting to homogenize the top 0.1 m of soil, incorporate P and K fertilizers, as well as previously accumulated surface residues. Since the tillage operation, the site has been under no-till management until the harvest of 2005. Following harvest, a conservation-plow tillage operation was initiated where a small amount of N fertilizer is sprayed on the residue immediately prior to the plow operation. Approximately 1/3 of the crop residue is left on the surface. The post-harvest conservation-plow operation continues as the current practice.

  5. Hydrology of a groundwater-irrigated rice field in Bangladesh: Seasonal and daily mechanisms of infiltration

    NASA Astrophysics Data System (ADS)

    Neumann, Rebecca B.; Polizzotto, Matthew L.; Badruzzaman, A. Borhan M.; Ali, M. Ashraf; Zhang, Zhongyuan; Harvey, Charles F.

    2009-09-01

    Flow through a groundwater-irrigated rice field in Bangladesh was characterized with data collected from a transect of tensiometers and time domain reflectometry sensors, novel tracer tests, infiltration tests, soil core analyses, and calculated water budgets. The combined data captured the dynamic hydrologic behavior of the rice field over an entire growing season, which included many irrigation events. Recharge to the aquifer flowed from the surface of the rice field through preferential flow paths located in the subsoil beneath the plowed surface of the field and in the bunds, the raised boundaries around the perimeter of the field. Water that remained within the soil matrix did not recharge the aquifer. Bund flow was the dominant loss for the field because the bulk hydraulic conductivity of the soil beneath the bunds was greater than that in the plowed and planted region of the rice field. Each year, farmers plow the rice fields, destroying cracks and decreasing the conductivity of the shallow soil, but leave the bunds unplowed because they follow property boundaries. We determined bund flow with a daily water balance and confirmed its importance by comparing irrigation losses among fields of different sizes and geometries and hence different ratios of perimeter to area. The perimeter-to-area ratio predicted the fraction of water lost down the bunds for these and other fields located throughout Southeast Asia. Finally, we determined the economic and environmental benefits of reducing bund flow.

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

    USGS Publications Warehouse

    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 <15%. The increased flooding has likely increased access to food resources for wintering waterfowl, but this benefit may not be available to some goose species, and may be at least partially countered by the increase of plowed fields, especially those left dry, and the decrease of fields left as 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.

  7. An improved whole cell pertussis vaccine with reduced content of endotoxin

    PubMed Central

    Dias, Waldely Oliveira; van der Ark, Arno A.J.; Sakauchi, Maria Aparecida; Kubrusly, Flávia Saldanha; Prestes, Ana Fabíola R.O.; Borges, Monamaris Marques; Furuyama, Noemi; Horton, Denise S.P.Q.; Quintilio, Wagner; Antoniazi, Marta; Kuipers, Betsy; van der Zeijst, Bernard A.M.; Raw, Isaias

    2013-01-01

    An improved whole cell pertussis vaccine, designated as Plow, which is low in endotoxicity due to a chemical extraction of lipo-oligosaccharide (LOS) from the outer membrane, was evaluated for safety, immunogenicity and potency, comparatively to a traditional whole cell pertussis vaccine. Current whole cell pertussis vaccines are effective but contain large quantities of endotoxin and consequently display local and systemic adverse reactions after administration. Endotoxin is highly inflammatory and contributes considerably to the reactogenicity as well as the potency of these vaccines. In contrast, acellular pertussis vaccines hardly contain endotoxin and are significantly less reactogenic, but their elevated costs limit their global use, especially in developing countries. In this paper, bulk products of Plow and a traditional whole cell vaccine, formulated as plain monocomponents or combined with diphtheria and tetanus toxoids (DTPlow or DTP, respectively) were compared by in vitro and in vivo assays. Chemical extraction of LOS resulted in a significant decrease in endotoxin content (20%) and a striking decline in endotoxin related toxicity (up to 97%), depending on the used in vitro or in vivo test. The LOS extraction did not affect the integrity of the product and, more importantly, did not affect the potency and/or stability of DTPlow. Moreover, hardly any differences in antibody and T-cell responses were observed. The development of Plow is a significant improvement regarding the endotoxicity of whole cell pertussis vaccines and therefore a promising and affordable alternative to currently available whole cell or acellular pertussis vaccines for developing countries. PMID:23291935

  8. Impacts of conservation tillage on the hydrological and agronomic performance of fanya juus in the upper Blue Nile (Abbay) river basin

    NASA Astrophysics Data System (ADS)

    Temesgen, M.; Uhlenbrook, S.; Simane, B.; van der Zaag, P.; Mohamed, Y.; Wenninger, J.; Savenije1, H. H. G.

    2012-01-01

    Adoption of soil conservation structures (SCS) has been low in high rainfall areas of Ethiopia mainly due to crop yield reduction, increased soil erosion following breaching of SCS, incompatibility with the tradition of cross plowing and water-logging behind SCS. A new type of conservation tillage (CT) involving contour plowing and the construction of invisible subsoil barriers using a modified Maresha winged "subsoiler" is suggested as a means to tackle these problems as an integral part of the SCS. We investigated the effect of integrating the CT with SCS on the surface runoff, water-logging, soil loss, crop yield and plowing convenience. The new approach of conservation tillage has been compared with traditional tillage (TT) on 5 farmers' fields in a high rainfall area in the upper Blue Nile (Abbay) river basin. Test crops were wheat [triticum vulgare] and tef [eragrostis tef]. Farmers found CT convenient to apply between SCS. Surface runoff appeared to be reduced under CT by 48 and 15%, for wheat and tef, respectively. As a result, CT reduced sediment yield by 51 and 9.5%, for wheat and tef, respectively. Significantly reduced water-logging was observed behind SCS in CT compared to TT. Grain yields of wheat and tef increased by 35 and 10%, respectively, although the differences were not statistically significant apparently due to high fertility variations among fields of participating farmers. Farmers who tested CT indicated that they will continue this practice in the future.

  9. Impacts of conservation tillage on the hydrological and agronomic performance of Fanya juus in the upper Blue Nile (Abbay) river basin

    NASA Astrophysics Data System (ADS)

    Temesgen, M.; Uhlenbrook, S.; Simane, B.; van der Zaag, P.; Mohamed, Y.; Wenninger, J.; Savenije, H. H. G.

    2012-12-01

    Adoption of soil conservation structures (SCS) has been low in high rainfall areas of Ethiopia mainly due to crop yield reduction, increased soil erosion following breaching of SCS, incompatibility with the tradition of cross plowing and water-logging behind SCS. A new type of conservation tillage (CT) involving contour plowing and the construction of invisible subsoil barriers using a modified Maresha winged "subsoiler" is suggested as a means to tackle these problems as an integral part of the SCS. We investigated the effect of integrating the CT with SCS on the surface runoff, water-logging, soil loss, crop yield and plowing convenience. The new approach of conservation tillage has been compared with traditional tillage (TT) on 5 farmers' fields in a high rainfall area in the upper Blue Nile (Abbay) river basin. Test crops were wheat [triticum vulgare] and tef [eragrostis tef]. Farmers found CT convenient to apply between SCS. Surface runoff appeared to be reduced under CT by 48 and 15%, for wheat and tef, respectively. As a result, CT reduced sediment yield by 51 and 9.5%, for wheat and tef, respectively. Significantly reduced water-logging was observed behind SCS in CT compared to TT. Grain yields of wheat and tef increased by 35 and 10%, respectively, although the differences were not statistically significant apparently due to high fertility variations among fields of participating farmers. Farmers who tested CT indicated that they will continue this practice in the future.

  10. Application of water jet assisted drag bit and pick cutter for the cutting of coal measure rocks. Final technical report. [Tests of combination in different rocks

    SciTech Connect

    Ropchan, D.; Wang, F.D.; Wolgamott, J.

    1980-04-01

    A laboratory investigation was made of the effects of high pressure water jets on the cutting forces of drag bit cutters in sedimentary rocks. A hard and soft sandstone, shale and limestone were tested with commercially obtainable conical and plow type drag bits on the EMI linear cutting machine. About 1200 cuts were made at different bit penetration, jet orientation, and water pressure to determine the reduction of cutting forces on the bit from the use of the water jet. Both independent and interactive cutting was used. The greatest reduction in cutting forces were with both of the sandstones; the drag forces were reduced about 30 percent and the normal forces about 60 percent at 5000 psi water pressure with the nozzle behind the bit. The method was less effective in the shale, except at 10,000 psi water pressure the reduction in drag force was about 55 percent. Of the rocks tested, the limestone was least affected by the water jet. The cutting forces for the plow bit showed continuous change with wear so a machined conical bit was used for most of the testing. Tests with the plow bit did show a large reduction in cutting forces by using the water jet with worn bits. An economic analysis of equipping a drag bit tunnel boring machine indicated that the water jet system could reduce costs per foot in sandstone by up to 40 percent.

  11. Multiple cervical spinous process fractures in a novice golf player.

    PubMed

    Kim, Sei-Yoon; Chung, Sang Ki; Kim, Dong-Yun

    2012-12-01

    Avulsion of spinous process, also called Clay-shoveler's fracture, is most prevalent among those engaged in hard physical labor. To the best of the author's knowledge, only one case of multiple spinous process fractures of the upper thoracic spine in a novice golfer has been reported. A 45-year-old female presented with intractable posterior neck pain. The patient experienced a sharp, sudden pain on the neck while swinging a golf club, immediately after the club head struck the ground. Dynamic cervical radiographic findings were C6 and C7 spinous process fractures. Magnetic resonance imaging revealed C6 and C7 spinous process fractures without spinal cord pathology. The patient was treated with pain medications and cervical bracing. The patient's pain gradually improved. The injury mechanism was speculated to be similar to Clay-shoveler's fracture. Lower cervical spinous process fractures can be associated with a golf swing. If the patient complains of long lasting neck pain and has a history of golf activity, further study should be conducted to rule out lower cervical spinous fracture. PMID:23346334

  12. A new marine reptile from the Triassic of China, with a highly specialized feeding adaptation

    NASA Astrophysics Data System (ADS)

    Cheng, Long; Chen, Xiao-Hong; Shang, Qing-Hua; Wu, Xiao-Chun

    2014-03-01

    The Luoping fauna (Anisian, Middle Triassic) is probably the oldest of Triassic faunas in Guizhou-Yunnan area, China. The reptilian assemblage is comprised of ichthyosaurs, a number of sauropterygians (pachypleurosaur-like forms), saurosphargids, protorosaurs, and archosauriforms. Here, we report on a peculiar reptile, newly found in this fauna. Its dentition is fence or comb-like and bears more than 175 pleurodont teeth in each ramus of the upper and lower jaws, tooth crown is needle-like distally and blade-shaped proximally; its rostrum strongly bends downward and the anterior end of its mandible expands both dorsally and ventrally to form a shovel-headed structure; and its ungual phalanges are hoof-shaped. The specializations of the jaws and dentition indicate that the reptile may have been adapted to a way of bottom-filter feeding in water. It is obvious that such delicate teeth are not strong enough to catch prey, but were probably used as a barrier to filter microorganisms or benthic invertebrates such as sea worms. These were collected by the specialized jaws, which may have functioned as a shovel or pushdozer (the mandible) and a grasper or scratcher (the rostrum). Our preliminary analysis suggests that the new reptile might be more closely related to the Sauropterygia than to other marine reptiles.

  13. Nonmetric tooth crown traits in a Sri Lankan aboriginal Vedda population.

    PubMed

    Peiris, H R D; Arambawatta, A K S; Hewapathirana, T N; Nanayakkara, C D; Chandrasekara, M; Wickramanayake, E

    2011-12-01

    This study was conducted to determine the frequencies of non-metric tooth crown traits of Vedda of Sri Lanka and to investigate the affinities of these morphological variations with those of other world populations. Fifty dental plaster casts were observed. The Arizona State University dental anthropology system was adopted for classification of the 16 traits observed. We used 13 traits to compare the Vedda and other world populations. Using the frequencies of 13 traits, Smith Mean Measure of Divergence was calculated to determine inter-population distances. Affinities among the Vedda and other world populations were expressed in two dimensions of the principal coordinate analysis. Cusp number in mandibular second molar and hypocone absence in maxillary second molar had the highest frequency at 95.9% and 93.8%, respectively. Shovelling, double shovelling in the maxillary central incisor and deflecting wrinkle in the mandibular first molar had the lowest frequency at 0%. The principal coordinate analysis showed that Sino American and Western Eurasian populations were separated in negative and positive directions in the first principal coordinate axis. Vedda located with the Western Eurasian population groups. Sahul and Sunda Pacific populations located in the intermediate position between Sino American and Western Eurasian populations. The dental phenotype of Vedda has close affinities with those of early south Asian populations. They are far different from Sino American and Sunda pacific populations. Vedda shows closer affinities to Sahul Pacific and South African (Bantu) populations. PMID:21975363

  14. Intensive archaeological survey of the F/H Surface Enhancement Project Area, Savannah River Site, Aiken and Barnwell Counties, South Carolina

    SciTech Connect

    Sassaman, K.E.; Gillam, J.C.

    1993-08-01

    Twelve archaeological sites and four artifact occurrences were located by intensive survey of two tracts of land for the F and H Surface Enhancement Project on the Savannah River Site, Aiken and Barnwell Counties, South Carolina. Fieldwork in the 480-acre project area included surface reconnaissance of 3.6 linear kilometers of transects, 140 shovel tests along 4.2 linear kilometers of transects, an additional 162 shovel tests at sites and occurrences, and the excavation of six l {times} 2 m test units. All but one of the sites contained artifacts of the prehistoric era; the twelfth site consists of the remains of a twentieth-century home place. The historic site and six of the prehistoric sites consist of limited and/or disturbed contexts of archaeological deposits that have little research potential and are therefore considered ineligible for nomination to the National Register of Historic Places (NRHP). The remaining five sites have sufficient content and integrity to yield information important to ongoing investigations into upland site use. These sites (38AK146, 38AK535, 38AK539, 38AK541, and 38AK543) are thus deemed eligible for nomination to the NRHP and the Savannah River Archaeological Research Program (SRARP) recommends that they be preserved through avoidance or data recovery.

  15. A new marine reptile from the Triassic of China, with a highly specialized feeding adaptation.

    PubMed

    Cheng, Long; Chen, Xiao-Hong; Shang, Qing-Hua; Wu, Xiao-Chun

    2014-03-01

    The Luoping fauna (Anisian, Middle Triassic) is probably the oldest of Triassic faunas in Guizhou-Yunnan area, China. The reptilian assemblage is comprised of ichthyosaurs, a number of sauropterygians (pachypleurosaur-like forms), saurosphargids, protorosaurs, and archosauriforms. Here, we report on a peculiar reptile, newly found in this fauna. Its dentition is fence or comb-like and bears more than 175 pleurodont teeth in each ramus of the upper and lower jaws, tooth crown is needle-like distally and blade-shaped proximally; its rostrum strongly bends downward and the anterior end of its mandible expands both dorsally and ventrally to form a shovel-headed structure; and its ungual phalanges are hoof-shaped. The specializations of the jaws and dentition indicate that the reptile may have been adapted to a way of bottom-filter feeding in water. It is obvious that such delicate teeth are not strong enough to catch prey, but were probably used as a barrier to filter microorganisms or benthic invertebrates such as sea worms. These were collected by the specialized jaws, which may have functioned as a shovel or pushdozer (the mandible) and a grasper or scratcher (the rostrum). Our preliminary analysis suggests that the new reptile might be more closely related to the Sauropterygia than to other marine reptiles. PMID:24452285

  16. The effects of body properties on sand-swimming

    NASA Astrophysics Data System (ADS)

    Sharpe, Sarah; Kuckuk, Robyn; Koehler, Stephan; Goldman, Daniel

    2014-03-01

    Numerous animals locomote effectively within sand, yet few studies have investigated how body properties and kinematics contribute to subsurface performance. We compare the movement strategies of two desert dwelling subsurface sand-swimmers exhibiting disparate body forms: the long-slender limbless shovel-nosed snake (C. occipitalis) and the relatively shorter sandfish lizard (S. scincus). Both animals ``swim'' subsurface using a head-to-tail propagating wave of body curvature. We use a previously developed granular resistive force theory to successfully predict locomotion of performance of both animals; the agreement with theory implies that both animal's swim within a self-generated frictional fluid. We use theory to show that the snake's shape (body length to body radius ratio), low friction and undulatory gait are close to optimal for sand-swimming. In contrast, we find that the sandfish's shape and higher friction are farther from optimal and prevent the sandfish from achieving the same performance as the shovel-nosed snake during sand-swimming. However, the sandfish's kinematics allows it to operate at the highest performance possible given its body properties. NSF PoLS

  17. Duck nest success in the prairie pothole region

    USGS Publications Warehouse

    Klett, A.T.; Shaffer, T.L.; Johnson, D.H.

    1988-01-01

    We estimated nest success of mallard (Anas platyrhynchos), gadwall (A. strepera), blue-winged teal (A. discors), northern shoveler (A. clypeata), and northern pintail (A. acuta) for 5 regions in North Dakota, South Dakota, and Minnesota, for 1-3 periods between 1966 and 1984, and for 8 habitat classes. We obtained composite estimates of nest success for regions and periods by weighting each habitat proportional to the number of nest initiations. The distribution of nest initiations was derived from estimates of breeding populations, preferences of species for nesting habitats, and availability of habitats. Nest success rates ranged from <5 to 36% among regions, periods, and species. Rates were lowest in western Minnesota (MNW) and eastern North Dakota (NDE), intermediate in central North Dakota (NDC) and eastern South Dakota (SDE), and highest in central South Dakota (SDC). In regions with comparable data, no consistent trend in nest success was apparent from early to late periods. Gadwalls and blue-winged teal nested more successfully than mallards and pintails; the relative success of shovelers varied regionally. Ducks nesting in idle grassland were the most successful and those nesting in cropland were least successful. Mammalian predation was the major cause of nesting failure (54-85%) in all habitats, but farming operations resulted in 37 and 27% of the nesting failures in cropland and hayland, respectively. Most of the populations studied were not self-sustaining.

  18. History of reclamation: the times - they are a changin'

    SciTech Connect

    Cardwell, S.P.; Sanz, L.O.

    1985-12-09

    Surface mining in Kentucky and the US has risen from rather sporadic beginnings in the late 1800's to a full fledged, heavily regulated industry in the 1980's. The industry has undergone a more traumatic regulatory metamorphosis in the past twenty-five years than any other single industry in the US. Reclamation requirements have gone from supplying a simple mine registration with the appropriate agency immediately prior to beginning operations to spending as much as 18-24 months collecting data for what amounts to a mini-environmental impact statement which must be submitted as part of a lengthy application several months prior to actual start-up of the operation itself. Increasingly stringent laws have been the result of two main forces: (1) Increasing citizen concern to save the environment and (2) Increasingly efficient technology which can both mine more coal (and as a result disturb more ground). This paper will follow the evolution of the coal mining and reclamation industry, from its beginning in the late nineteenth century when surface mining was conducted with a pick-and-shovel and a mule-drawn scraper to the present day, when a 100 cu.yd. stripping shovel is almost commonplace. Particular attention will be given to the relationship between the evolving technology and the increasingly stringent laws. 33 references.

  19. Differences in bill form of the oystercatcher haematopus ostralegus; a dynamic adaptation to specific foraging techniques

    NASA Astrophysics Data System (ADS)

    Swennen, C.; De Bruijn, L. L. M.; Duiven, P.; Leopold, M. F.; Marteijn, E. C. L.

    In wintering European oystercatchers 3 bill types: pointed, chisel-shaped, and blunt were found as well as their intermediates. The distribution of the different bill types varied widely in both time and space. Pointed bills had a larger mean length than both chisel-shaped and blunt bills, and occurred more often in young birds than in adults, and more often in females than in males. On an average, females had longer bills than males. In oystercatchers in the Wadden Sea area bill length was found to increase with age, but in the Delta area no increase was found. In semi-natural cage experiments each bill type proved to be most suitable for a specific manner of localization and handling of prey. Bills of individual oystercatchers were shown to change shape when the bird was forced to change its feeding method. A change in method accompanied by a gradual change in bill form only caused a temporary loss of feeding efficiency. It is concluded that differences in bill length influence prey choice and feeding method and hence induce different bill forms. Age- and sex-dependent differences in bill length and form, together with the ability of the individual to adapt bill form and feeding behaviour, enable the oystercatcher to lessen interspecific competition and to respond to changing environmental conditions.

  20. Powder-Collection System for Ultrasonic/Sonic Drill/Corer

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Chang, Zensheu; Blake, David; Bryson, Charles

    2005-01-01

    A system for collecting samples of powdered rock has been devised for use in conjunction with an ultrasonic/sonic drill/corer (USDC) -- a lightweight, lowpower apparatus designed to cut into, and acquire samples of, rock or other hard material for scientific analysis. The USDC includes a drill bit, corer, or other tool bit, in which ultrasonic and sonic vibrations are excited by an electronically driven piezoelectric actuator. The USDC advances into the rock or other material of interest by means of a hammering action and a resulting chiseling action at the tip of the tool bit. The hammering and chiseling actions are so effective that unlike in conventional twist drilling, a negligible amount of axial force is needed to make the USDC advance into the material. Also unlike a conventional twist drill, the USDC operates without need for torsional restraint, lubricant, or a sharp bit. The USDC generates powder as a byproduct of the drilling or coring process. The purpose served by the present samplecollection system is to remove the powder from the tool-bit/rock interface and deliver the powder to one or more designated location(s) for analysis or storage

  1. Effects of Application Methods and Plastic Covers on Distribution of Cis- and Trans-1,3-Dichloropropene and Chloropicrin in Root Zone

    PubMed Central

    Ou, L.-T.; Thomas, J. E.; Allen, L. H.; McCormack, L. A.; Vu, J. C.; Dickson, D. W.

    2005-01-01

    This study examined the effects of three application methods (chisel injection, Avenger coulter injection, and drip irrigation) and two plastic films (polyethylene film [PE] and virtually impermeable film [VIF]) on distribution of cis- and trans- 1,3-dichloropropene (1,3-D) and chloropicrin (CP) in a Florida sandy soil after application of Telone C35 or Telone In-Line. Regardless of application method, VIF retained greater amounts of cis- and trans-1,3-D and CP in the root zone with longer residential time than PE. There was better retention of the three compounds in the root zone when applied with the Avenger coulter injection rig than chisel injection, especially in combination with VIF. Distribution of the three compounds in the root zone was less predictable when applied by drip irrigation. Following drip irrigation, more than 50% of the three compounds in the PE and VIF-covered beds was found near the end of the drip tapes in one experiment, whereas the distribution was much more uniform in the root zone in a second experiment. Among the three biologically active compounds, CP disappeared from the root zone more rapidly than cis- and trans-1,3-D, especially in the PE-covered beds. PMID:19262895

  2. Effects of foreign object damage from small hard particles on the high-cycle fatigue life of titanium-(6)aluminum-(4)vanadium

    NASA Astrophysics Data System (ADS)

    Hamrick, Joseph L., II

    Thin rectangular samples of Ti-6Al-4V were damaged by four methods to represent foreign object damage found in turbine engine blades: (1) impact with 2 mm. and 5 mm diameter glass spheres at 305 m/s, (2) impact with 2 mm and 4 mm diameter steel spheres at 305 m/s, (3) quasi-static displacement controlled indentation using steel chisels with 1 mm, 2 nun and 5 mm diameter tips and (4) shearing notches with a 2 mm. diameter chisel point under a quasi-static loading condition. Finite element analysis was used to study the relationship between the stress state created by the plastic damage and the fatigue strength. A new method of quantifying the amount of plastic damage from multiple methods was developed. The fatigue strength required for crack initiation at 10E7 cycles was found to be a function of the total depth from the edge of the undeformed specimen up to the end of the plastically deformed zone. For damage depths less than 1750 mum, the reduction in fatigue strength is proportional to the depth of total damage. For depths > 1750 mum, there appears to be a threshold value of fatigue strength.

  3. Inoculum Potential of Fusarium spp. Relates to Tillage and Straw Management in Norwegian Fields of Spring Oats

    PubMed Central

    Hofgaard, Ingerd S.; Seehusen, Till; Aamot, Heidi U.; Riley, Hugh; Razzaghian, Jafar; Le, Vinh H.; Hjelkrem, Anne-Grete R.; Dill-Macky, Ruth; Brodal, Guro

    2016-01-01

    The increased occurrence of Fusarium-mycotoxins in Norwegian cereals over the last decade, is thought to be caused by increased inoculum resulting from more cereal residues at the soil surface as a result of reduced tillage practices. In addition, weather conditions have increasingly promoted inoculum development and infection by Fusarium species. The objective of this work was to elucidate the influence of different tillage regimes (autumn plowing; autumn harrowing; spring plowing; spring harrowing) on the inoculum potential (IP) and dispersal of Fusarium spp. in spring oats. Tillage trials were conducted at two different locations in southeast Norway from 2010 to 2012. Oat residues from the previous year’s crop were collected within a week after sowing for evaluation. IP was calculated as the percentage of residues infested with Fusarium spp. multiplied by the proportion of the soil surface covered with residues. Fusarium avenaceum and F. graminearum were the most common Fusarium species recovered from oat residues. The IP of Fusarium spp. was significantly lower in plowed plots compared to those that were harrowed. Plowing in either the autumn or spring resulted in a low IP. Harrowing in autumn was more effective in reducing IP than the spring harrowing, and IP levels for the spring harrowed treatments were generally higher than all other tillage treatments examined. Surprisingly low levels of F. langsethiae were detected in the residues, although this species is a common pathogen of oat in Norway. The percentage of the residues infested with F. avenaceum, F. graminearum, F. culmorum, and F. langsethiae generally related to the quantity of DNA of the respective Fusarium species determined using quantitative PCR (qPCR). Fusarium dispersal, quantified by qPCR analysis of spore trap samples collected at and after heading, generally corresponded to the IP. Fusarium dispersal was also observed to increase after rainy periods. Our findings are in line with the

  4. Cascading effect of economic globalization on human risks of scrub typhus and tick-borne rickettsial diseases.

    PubMed

    Kuo, Chi-Chien; Huang, Jing-Lun; Shu, Pei-Yun; Lee, Pei-Lung; Kelt, Douglas A; Wang, Hsi-Chieh

    2012-09-01

    The increase in global travel and trade has facilitated the dissemination of disease vectors. Globalization can also indirectly affect vector-borne diseases through the liberalization of cross-border trade, which has far-reaching, worldwide effects on agricultural practices and may in turn influence vectors through the modification of the ecological landscape. While the cascading effect of economic globalization on vector-borne diseases, sometimes acting synergistically with regional agricultural policy, could be substantial and have significant economic, agricultural, and public health implications, research into this remains very limited. We evaluated how abandonment of rice paddies in Taiwan after joining the World Trade Organization, along with periodic plowing, an agricultural policy to reduce farm pests in abandoned fields can unexpectedly influence risks to diseases transmitted by ticks and chiggers (larval trombiculid mites), which we collected from their small-mammal hosts. Sampling was limited to abandoned (fallow) and plowed fields due to the challenge of trapping small mammals in flooded rice paddies. Striped field mice (Apodemus agrarius) are the main hosts for both vectors. They harbored six times more ticks and three times more chiggers in fallow than in plowed plots. The proportion of ticks infected with Rickettsia spp. (etiologic agent of spotted fever) was three times higher in fallow plots, while that of Orientia tsutsugamushi (scrub typhus) in chiggers was similar in both treatments. Fallow plots had more ground cover and higher vegetation than plowed ones. Moreover, ticks and chiggers in both field types were dominated by species known to infest humans. Because ticks and chiggers should exhibit very low survival in flooded rice paddies, we propose that farm abandonment in Taiwan, driven by globalization, may have inadvertently led to increased risks of spotted fever and scrub typhus. However, periodic plowing can unintentionally mitigate vector

  5. Inoculum Potential of Fusarium spp. Relates to Tillage and Straw Management in Norwegian Fields of Spring Oats.

    PubMed

    Hofgaard, Ingerd S; Seehusen, Till; Aamot, Heidi U; Riley, Hugh; Razzaghian, Jafar; Le, Vinh H; Hjelkrem, Anne-Grete R; Dill-Macky, Ruth; Brodal, Guro

    2016-01-01

    The increased occurrence of Fusarium-mycotoxins in Norwegian cereals over the last decade, is thought to be caused by increased inoculum resulting from more cereal residues at the soil surface as a result of reduced tillage practices. In addition, weather conditions have increasingly promoted inoculum development and infection by Fusarium species. The objective of this work was to elucidate the influence of different tillage regimes (autumn plowing; autumn harrowing; spring plowing; spring harrowing) on the inoculum potential (IP) and dispersal of Fusarium spp. in spring oats. Tillage trials were conducted at two different locations in southeast Norway from 2010 to 2012. Oat residues from the previous year's crop were collected within a week after sowing for evaluation. IP was calculated as the percentage of residues infested with Fusarium spp. multiplied by the proportion of the soil surface covered with residues. Fusarium avenaceum and F. graminearum were the most common Fusarium species recovered from oat residues. The IP of Fusarium spp. was significantly lower in plowed plots compared to those that were harrowed. Plowing in either the autumn or spring resulted in a low IP. Harrowing in autumn was more effective in reducing IP than the spring harrowing, and IP levels for the spring harrowed treatments were generally higher than all other tillage treatments examined. Surprisingly low levels of F. langsethiae were detected in the residues, although this species is a common pathogen of oat in Norway. The percentage of the residues infested with F. avenaceum, F. graminearum, F. culmorum, and F. langsethiae generally related to the quantity of DNA of the respective Fusarium species determined using quantitative PCR (qPCR). Fusarium dispersal, quantified by qPCR analysis of spore trap samples collected at and after heading, generally corresponded to the IP. Fusarium dispersal was also observed to increase after rainy periods. Our findings are in line with the general

  6. Age-class separation of blue-winged ducks

    USGS Publications Warehouse

    Hohman, W.L.; Moore, J.L.; Twedt, D.J.; Mensik, John G.; Logerwell, E.

    1995-01-01

    Accurate determination of age is of fundamental importance to population and life history studies of waterfowl and their management. Therefore, we developed quantitative methods that separate adult and immature blue-winged teal (Anas discors), cinnamon teal (A. cyanoptera), and northern shovelers (A. clypeata) during spring and summer. To assess suitability of discriminant models using 9 remigial measurements, we compared model performance (% agreement between predicted age and age assigned to birds on the basis of definitive cloacal or rectral feather characteristics) in different flyways (Mississippi and Pacific) and between years (1990-91 and 1991-92). We also applied age-classification models to wings obtained from U.S. Fish and Wildlife Service harvest surveys in the Mississippi and Central-Pacific flyways (wing-bees) for which age had been determined using qualitative characteristics (i.e., remigial markings, shape, or wear). Except for male northern shovelers, models correctly aged lt 90% (range 70-86%) of blue-winged ducks. Model performance varied among species and differed between sexes and years. Proportions of individuals that were correctly aged were greater for males (range 63-86%) than females (range 39-69%). Models for northern shovelers performed better in flyway comparisons within year (1991-92, La. model applied to Calif. birds, and Calif. model applied to La. birds: 90 and 94% for M, and 89 and 76% for F, respectively) than in annual comparisons within the Mississippi Flyway (1991-92 model applied to 1990-91 data: 79% for M, 50% for F). Exclusion of measurements that varied by flyway or year did not improve model performance. Quantitative methods appear to be of limited value for age separation of female blue-winged ducks. Close agreement between predicted age and age assigned to wings from the wing-bees suggests that qualitative and quantitative methods may be equally accurate for age separation of male blue-winged ducks. We interpret annual

  7. Estimating natal dispersal movement rates of female European ducks with multistate modeling

    USGS Publications Warehouse

    Blums, P.; Nichols, J.D.; Hines, J.E.; Lindberg, M.S.; Mednis, A.

    2003-01-01

    1. We used up to 34 years of capture-recapture data from about 22,100 new releases of day-old female ducklings and multistate modelling to test predictions about the influence of environmental, habitat and management factors on natal dispersal probability of three species of ducks within the Engure Marsh, Latvia. 2. The mean natal dispersal distances were very similar (c . 0?6-0?7 km) for all three species and were on average 2?7 times greater than breeding dispersal distances recorded within the same study system. 3. We were unable to confirm the kinship hypothesis and found no evidence that young first-nesting females nested closer to their relatives (either mother or sister) than to the natal nest. 4. Young female northern shovelers, like adults, moved from small islands to the large island when water level was high and vice versa when water level was low before the construction of elevated small islands. Movement probabilities between the two strata were much higher for young shovelers than adults, suggesting that young birds had not yet developed strong fidelity to the natal site. Movements of young female tufted ducks, unlike those of shovelers, were not dependent on water level fluctuations and reflected substantial flexibility in choice of first nesting sites. 5. Data for young birds supported our earlier conclusion that common pochard nesting habitats in black-headed gull colonies were saturated during the entire study period. Young females, like the two adult age groups, moved into and out of colonies with similar probability. Fidelity probability of female pochards to each stratum increased with age, being the lowest (0?62) for young (DK) females, intermediate (0?78) for yearlings (SY) and the highest (0?84) for adult (ASY) females. 6. Young female tufted ducks, like adults, showed higher probabilities of moving from islands to emergent marshes when water levels were higher both before and after habitat management. The relationship between the spring

  8. The Use of Soil in Criminal Investigations

    NASA Astrophysics Data System (ADS)

    Dawson, Lorna; Fitzpatrick, Robert

    2013-04-01

    Forensic soil science, as a newly developed discipline of soil science, has matured to the extent that well-defined questions and successful crime scene investigations are being addressed in increasingly refined ways to assist law enforcement agencies. Soils, rocks, regolith, minerals and man-made mineral particles such as bricks (i.e. referred to "human-made" soil materials) are being used in specialised forensic investigations to associate/disassociate a sample taken from an item, such as shoes, clothing, shovel or vehicle, with a specific location. The majority of forensic cases involving soil materials are usually overwhelmingly complex, and the challenges of associating relevant information from one source with another, often requires the use and development of sophisticated field and laboratory methods. Through examples from case studies, this presentation will demonstrate how advanced field and laboratory approaches have been critical in developing coherent, predictive, soil models, from landscape to microscopic scales, to help contribute to soil-based criminal investigations in both Australia and Scotland. To demonstrate the critical importance of soil materials in forensic investigations, the following 2 case studies, which tackle difficult problems at a range of scales involving highly complex issues, will be presented: •The use of soil evidence to help solve a double murder case. This investigation used morphological, chemical, physical and mineralogical properties to identify similarities between soil-regolith found on a shovel taken from the suspect's vehicle and wetland soil-regolith subsequently located in the bottom of a quarry (Fitzpatrick and Raven, 2012). •The use of soil and related material to help search and to provide evidence in a murder case. This investigation used soil mineralogical and organic properties to identify similarities between sand found on a shovel and sand subsequently located at a beach. Results illustrate the benefit of

  9. Quantification of forces required for stabbing with screwdrivers and other blunter instruments.

    PubMed

    Parmar, Kiran; Hainsworth, Sarah Victoria; Rutty, Guy Nathan

    2012-01-01

    In the UK, stabbing is the most common cause of homicide. The weapons used include knives, swords, screwdrivers and glass shards. Quantifying the exact force used in a stabbing incident is considered to be a difficult area due to the large number of variables present, such as sharpness of weapon, angle of attack and relative movements of the people involved. Having quantifiable data would allow a forensic pathologist to make a more informed decision when it comes to answering the commonly posed question in court "what was the degree of force involved in the stabbing incident?" The answer to this question is considered significant in determining an alleged assailant's intent to cause harm. This paper presents results of the first detailed study relating geometry of screwdrivers to the forces required for penetration. Additionally, a range of other blunt weapons such as pens and chisels have also been studied. A silicone rubber-foam analogue has been used as the main skin simulant owing to it having similar mechanical properties to that of human skin and giving highly repeatable results. Different screwdrivers of varying shape and size have been tested (i.e. slotted, Phillips, posidriv and Torx), along with other implements including chisels and pens. The weapon geometry was characterised and related to the peak force required for penetration. Our results show that there is a direct correlation between the cross-sectional area of a screwdriver head and the amount of force required for penetration. Screwdrivers with larger cross-sectional areas require a significantly greater force to penetrate (forces in the region of 100-120 N) but "sharper" slotted screwdrivers penetrate with much lower forces (~30 N). The forces required for penetrating the rubber-foam analogue with screwdrivers are higher than for "sharp" knives, but in some cases similar to the forces required for stabbing with "blunt" knives. For the other weapons such as chisels and biros, the force required

  10. Effects of management of ecosystem carbon pools and fluxes in grassland ecosystems

    NASA Astrophysics Data System (ADS)

    Ryals, R.; Silver, W. L.

    2010-12-01

    Grasslands represent a large land-use footprint and have considerable potential to sequester carbon (C) in soil. Climate policies and C markets may provide incentives for land managers to pursue strategies that optimize soil C storage, yet we lack robust understanding of C sequestration in grasslands. Previous research has shown that management approaches such as organic amendments or vertical subsoiling can lead to larger soil C pools. These management approaches can both directly and indirectly affect soil C pools. We used well-replicated field experiments to explore the effects of these management strategies on ecosystem C pools and fluxes in two bioclimatic regions of California (Sierra Foothills Research and Extension Center (SFREC) and Nicasio Ranch). Our treatments included an untreated control, compost amendments, plowed (vertical subsoil), and compost + plow. The experiment was conducted over two years allowing us to compare dry (360 mm) and average (632 mm) rainfall conditions. Carbon dioxide (CO2) fluxes were measured weekly using a LI-8100 infrared gas analyzer. Methane (CH4) and nitrous oxide (N2O) fluxes were measured monthly using static flux chambers. Aboveground and belowground biomass were measured at the end of the growing season as an index of net primary productivity (NPP) in the annual plant dominated system. Soil moisture and temperature were measured continuously and averaged on hourly and daily timescales. Soil organic C and N concentrations were measured prior to the application of management treatments and at the ends of each growing season. Soils were collected to a 10 cm depth in year one and at four depth increments (0-10, 10-30, 30-50, and 50-100 cm) in year two. Soil C and N concentrations were converted to content using bulk density values for each plot. During both growing seasons, soil respiration rates were higher in the composted plots and lower in the plowed plots relative to controls at both sites. The effects on C loss via

  11. Post-fire hydrologic response in Central Portugal. A four years study at microplot scale.

    NASA Astrophysics Data System (ADS)

    Vieira, Diana; Malvar, Maruxa; Martins, Martinho; Machado, Ana; Nunes, João; Keizer, Jacob

    2014-05-01

    Wildfires are a natural phenomenon in regions with a Mediterranean-type climate. However, their present-day widespread occurrence in southern Europe is unprecedented and strongly reflects human activity such as ignition, land-use changes, land abandonment and introduction of highly flammable plantations. Besides wildfires, post-fire management practices such as plowing, terracing, clearcutting and logging should also be considered, since their occurrence is getting increasingly common. And, in a long-term period these practices seem to be executed intercalated with repeated fire occurrences in the same site, sharing the impacts together with fire in an escalated degradational effect. In this sense, the work presented here concerns four years of runoff and erosion data at microplot scale after the wildfire, comparing different land management practices that occurred before the fire. Preliminary results indicate that in four years of monitoring, runoff is constantly higher in plowed sites than in the unplowed ones, with the exception of the first year. Regarding soil losses the plowed plots present always higher sediment rates than the unplowed ones. The comparison between two unplowed sites with different land uses, indicate higher runoff and erosion risk for pine comparatively to the eucalypt ones, however the reduced soil depth in the first can have an important role in these differences. Following these facts, the aim of the present work is to answer the following research questions: i) Do these four years of observations fit with the window of disturbance model presented by Prosser and Williams (1998). or the alternative version by Wittenberg and Inbar (2009)?; ii) Does pre-fire disturbances (wildfire, land use changes and land management practices) still have repercussions after wildfire?; In what sense does four years of intensive monitoring provides that one year couldn't provide?

  12. Transformation and sorption of the veterinary antibiotic sulfadiazine in two soils: a short-term batch study

    NASA Astrophysics Data System (ADS)

    Kasteel, Roy; Mboh, Cho; Unold, Myriam; Groeneweg, Joost; Vanderborght, Jan; Vereecken, Harry

    2010-05-01

    The worldwide use of veterinary antibiotics poses a continuous threat to the environment. There is, however, a lack of mechanistic studies on sorption and transformation processes for environmental assessment in soils. Two-weeks batch sorption experiments were performed with the antibiotic sulfadiazine (SDZ) in the plow layer and the subsoil of a loamy sand and a silty loam. The sorption and transformation parameters of SDZ and its main transformation products N1-2-(4-hydroxypyrimidinyl) benzenesulfanilamide (4-OH-SDZ) and 4-(2-iminopyrimidin-1(2H)-yl)-aniline (An-SDZ) were estimated using a global optimization algorithm. A two-stage, one-rate kinetic sorption model combined with a first-order transformation model adequately described the batch data. Sorption of SDZ was nonlinear (Freundlich), time-dependent, and affected by pH (speciation), with a higher sorption capacity for the loamy sand. Transformation of SDZ into 4-OH-SDZ occurred only in the liquid phase, with half-life values of about 1 month in the plow layers and about 6 months in the subsoils. Both the faster transformation rate in the plow layer compared to the subsoil and negligible transformation in the solid phase point to a microbial process for the formation of 4-OH-SDZ. Under the exclusion of light, An-SDZ was formed in substantial amounts in the silty loam only, with liquid phase half-life values of about 2 to 3 weeks. Despite the rather large parameter uncertainties, which may be reduced after the inclusion of additional information obtained from sequential solid phase extraction, the proposed method allows us to quantify and predict the fate of antibiotics in soils.

  13. Human energy expenditure in lowland rice cultivation in Malaysia.

    PubMed

    Nawi, N M; Yahya, A; Chen, G; Bockari-Gevao, S M; Maraseni, T N

    2012-01-01

    A study was undertaken to evaluate the human energy consumption of various field operations involved in lowland rice cultivation in Malaysia. Based on recorded average heart rates, fertilizing was found to be the most strenuous operation, with an average heart rate of 138 beats min(-1). There were no significant differences in the average heart rates of the subjects among the individual tasks within the first plowing, second plowing, and harvesting operations, with the average heart rates for these three tasks being 116, 106, and 106 beats min(-1), respectively. The corresponding energy expenditures were 3.90, 3.43, and 3.35 kcal min(-1). Loading the seed into the blower tank and broadcasting the seed were the most critical tasks for the seed broadcasting operation, with average heart rates of 124 and 136 beats min(-1), respectively. The highest energy expenditure of 418.38 kcal ha(-1) was observed for seed broadcasting, and the lowest energy expenditure of 127.96 kcal ha(-1) was for second plowing. The total seasonal human energy expenditure for rice cultivation was estimated to be 5810.71 kcal ha(-1), 55.7% of which was spent on pesticide spraying. Although the sample size in this study was relatively small, the results indicated that human energy expenditure per unit area (kcal ha(-1)) was positively linked to the average heart rate of the subjects and negatively linked to the field capacity. Thus, mechanization of certain tasks could decrease worker physical effort and fatigue and increase production. PMID:22458015

  14. Cross-Site Soil Microbial Communities under Tillage Regimes: Fungistasis and Microbial Biomarkers

    PubMed Central

    Yrjälä, Kim; Alakukku, Laura; Palojärvi, Ansa

    2012-01-01

    The exploitation of soil ecosystem services by agricultural management strategies requires knowledge of microbial communities in different management regimes. Crop cover by no-till management protects the soil surface, reducing the risk of erosion and nutrient leaching, but might increase straw residue-borne and soilborne plant-pathogenic fungi. A cross-site study of soil microbial communities and Fusarium fungistasis was conducted on six long-term agricultural fields with no-till and moldboard-plowed treatments. Microbial communities were studied at the topsoil surface (0 to 5 cm) and bottom (10 to 20 cm) by general bacterial and actinobacterial terminal restriction fragment length polymorphism (T-RFLP) and phospholipid fatty acid (PLFA) analyses. Fusarium culmorum soil fungistasis describing soil receptivity to plant-pathogenic fungi was explored by using the surface layer method. Soil depth had a significant impact on general bacterial as well as actinobacterial communities and PLFA profiles in no-till treatment, with a clear spatial distinction of communities (P < 0.05), whereas the depth-related separation of microbial communities was not observed in plowed fields. The fungal biomass was higher in no-till surface soil than in plowed soil (P < 0.07). Soil total microbial biomass and fungal biomass correlated with fungistasis (P < 0.02 for the sum of PLFAs; P < 0.001 for PLFA 18:2ω6). Our cross-site study demonstrated that agricultural management strategies can have a major impact on soil microbial community structures, indicating that it is possible to influence the soil processes with management decisions. The interactions between plant-pathogenic fungi and soil microbial communities are multifaceted, and a high level of fungistasis could be linked to the high microbial biomass in soil but not to the specific management strategy. PMID:22983972

  15. [Modeling the Cd accumulation in agricultural soil irrigated with reclaimed water].

    PubMed

    Zhao, Zhong-Ming; Chen, Wei-Ping; Jiao, Wen-Tao; Wang, Mei-E

    2012-12-01

    Recent years, soil pollution of heavy metal has affected human life seriously, especially in farmland. Heavy metal pollution in farmland is mainly caused by irrigation, fertilizing and atmospheric fallout. As the character of heavy metal input in farmland is chronic and low dosage, application of model would be more suitable than routine methods to illustrate the dynamic changes of heavy metals in soil. In this paper, we use the model of STEM-profile to analyze and predict Cd pollution in farmland in Tongzhou, Beijing, based on the data from field survey. The results showed that: the concentration of Cd in this land would exceed the national soil environment standard after 100 years under current situations, reaching 0.866 mg x kg(-1) in plow layer. Studies of the influence of the amount and the form of inputs and the amount of irrigation water on the distribution of Cd in soil showed that irrigated with reclaimed water or fertilized with organic manure could lead to accumulation of Cd in the soil, while groundwater irrigation with inorganic fertilization would not cause accumulation of Cd in soil. When Cd inputs changed from mineral to organic form, the concentration of Cd in plow layer would be 0.943 mg x kg(-1) after 100 year. When the amount of irrigation water increased from 0.8 ET to 1.5 ET and to 2.0 ET, the plow layer Cd content would be 0.952, 0.784 and 0.638 mg x kg(-1) respectively. PMID:23379131

  16. Specific features of the morphology and chemical properties of coarse-textured postagrogenic soils of the southern taiga, Kostroma oblast

    NASA Astrophysics Data System (ADS)

    Telesnina, V. M.; Vaganov, I. E.; Karlsen, A. A.; Ivanova, A. E.; Zhukov, M. A.; Lebedev, S. M.

    2016-01-01

    The properties of loamy sandy postagrogenic soils in the course of their natural overgrowing were studied in the southeastern part of Kostroma oblast. Micromorphological indications of tillage were preserved in these soils at least 35-40 years after the cessation of their agricultural use. In the course of the soil overgrowing with forest vegetation, the bulk density of the upper part of the former plow horizon decreased, the pH and the ash content of the litter horizon somewhat lowered with a simultaneous increase in the acidity of the upper mineral horizon, especially at the beginning of the formation of the tree stand. In 5-7 years after the cessation of tillage, the former plow horizon was differentiated with respect to the organic carbon content. The total pool of organic carbon in the upper 30 cm increased. In the course of the further development, in the postagrogenic soil under the 90to 100-year-old forest, the organic carbon pool in this layer became lower. The soil of the young fallow (5-7 years) was characterized by the higher values of the microbial biomass in the upper mineral horizon in comparison with that in the plowed soil. In general, the microbial biomass in the studied postagrogenic ecosystems (the soils of the fields abandoned in 2005 and 2000 and the soil under the secondary 40-year-old forest) was lower than that in the soil of the subclimax 90to 100-year-old forest. The enzymatic activity of the soils tends to increase during the succession. The restoration of the invertase and, partly, catalase activities to the values typical of the soils under mature forests takes place in about 40 years.

  17. Soil radiocesium distribution in rice fields disturbed by farming process after the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Harada, Naoki; Nonaka, Masanori

    2012-11-01

    A magnitude 9.0 earthquake and subsequent large tsunami hit the northeastern coast of Japan on March 11, 2011. This resulted in serious damage to the reactors of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), operated by the Tokyo Electric Power Company. Large amounts of radionuclides were released from the FDNPP, a proportion of which were deposited onto the ground. In this study, we investigated soil radiocesium contamination of rice fields in Aga and Minamiuonuma, Niigata, ~130 and 200 km away from the FDNPP, respectively, as Niigata is one of the largest rice growing regions in Japan. Soil samples were collected from the plow layer of five rice fields in August and September, 5-6 months after the FDNPP accident. Results showed that radiocesium concentrations (the sum of Cs-134 and Cs-137) in the rice soil samples were ~300 Bq (kg dry soil)(-1). All samples contained a Cs-134/Cs-137 activity ratio of 0.68-0.96 after correction to March 11, 2011, showing that the radiocesium released from the FDNPP were deposited on these areas. Although the rice fields had been disturbed by farming processes after the FDNPP accident, the depth distribution of radiocesium concentrations in the plow layers showed higher concentrations in the upper soil layers. This suggests that spring tillage, flooding and puddling performed before rice transplantation may not disperse radiocesium deposited on the surface through the whole plow layer. In addition, the planar distribution of radiocesium concentrations was examined near the water inlet in one of the rice fields. Highest activities were found aligned with the direction of irrigation water discharge, indicating that radioactivity levels in rice fields may be elevated by an influx of additional radionuclides, probably in irrigation water, during farming. PMID:23000550

  18. Transformation of soil organic matter in leached chernozems under minimized treatment in the forest-steppe of West Siberia

    NASA Astrophysics Data System (ADS)

    Sharkov, I. N.; Samokhvalova, L. M.; Mishina, P. V.

    2016-07-01

    Changes in the contents of total organic carbon and the carbon of easily mineralizable fractions of organic matter (labile humus, detritus, and mortmass) in the layers of 0-10, 10-25, and 0-25 cm were studied in leached chernozems ((Luvic Chernozems (Loamic, Aric)) subjected to deep plowing and surface tillage for nine years. In the layer of 0-25 cm, the content of Corg did not show significant difference between these two treatments and comprised 3.68-3.92% in the case of deep plowing and 3.63-4.08% in the case of surface tillage. Tillage practices greatly affected the distribution of easily mineralizable fractions of organic matter in the layers of 0-10 and 10-25 cm, though the difference between two treatments for the entire layer (0-25 cm) was insignificant. Surface tillage resulted in the increase in the contents of mortmass (by 59%), detritus (by 32%), and labile humus (by 8%) in the layer of 0-10 cm in comparison with deep plowing. At the same time, the contents of these fractions in the layer of 10-25 cm in the surface tillage treatment decreased by 67, 46, and 3%, respectively. The estimate of the nitrogen-mineralizing capacity made according to the data on the uptake of soil nitrogen by oat plants in a special greenhouse experiment confirmed the observed regularities of the redistribution of easily mineralizable organic matter fractions by the soil layers. In case of surface tillage, it increased by 23% in the layer of 0-10 cm; for the layer of 0-25 cm, no significant differences in the uptake of nitrogen by oat plants were found for the two studied treatments.

  19. Longwall mining of thin seams

    SciTech Connect

    Curth, E A

    1981-01-01

    Thin seam operations pose a challenge to the ingenuity of mining engineers to overcome the factor of human inconvenience in the restricted environment and associated high cost production. Surprisingly, low seam longwalls in the Federal Republic of Germany in an average thickness of 35 in. and dipping less than 18/sup 0/ come close to achieving the average production rate of all German longwall operations. They are all plow faces, and a consistent production of 3300 tons per day and a productivity of 40 tons per man shift are reported from one of the thin seam longwalls. These results were attained by reliable high-capacity equipment and roof support by shields that can be collapsed to as low as 22 inches. Maximum mining height for plow operated faces lies at 31.5 inches. Technology for mechanized mining of flat lying coalbeds less than 31.5 inches in thickness without rock cutting is not available, and firmness of coal, undulation of the strata, coalbed thickness variation, and the necessity of cutting rock, particularly through faults, set limits to plow application. The in-web shearer can be used in firm coal to a minimum mining height of 40 inches, and a daily production of 1650 to 2200 tons is reported from a longwall in the Saar district of Germany equipped with such a shearer and shields. Numerous in-web shearers are employed in the United Kingdom; reports as to their success are contradictory. Also, experience in the United States, though limited, has been negative. The steady increase in output from single drum shearer faces in Pennsylvania is a remarkable achievement, and occasional record breaking peaks in production indicate the potential of such mining. Technology development for the future is discussed.

  20. Effects of Different Tillage and Straw Return on Soil Organic Carbon in a Rice-Wheat Rotation System

    PubMed Central

    Zhu, Liqun; Hu, Naijuan; Yang, Minfang; Zhan, Xinhua; Zhang, Zhengwen

    2014-01-01

    Soil management practices, such as tillage method or straw return, could alter soil organic carbon (C) contents. However, the effects of tillage method or straw return on soil organic C (SOC) have showed inconsistent results in different soil/climate/cropping systems. The Yangtze River Delta of China is the main production region of rice and wheat, and rice-wheat rotation is the most important cropping system in this region. However, few studies in this region have been conducted to assess the effects of different tillage methods combined with straw return on soil labile C fractions in the rice-wheat rotation system. In this study, a field experiment was used to evaluate the effects of different tillage methods, straw return and their interaction on soil total organic C (TOC) and labile organic C fractions at three soil depths (0–7, 7–14 and 14–21 cm) for a rice-wheat rotation in Yangzhong of the Yangtze River Delta of China. Soil TOC, easily oxidizable C (EOC), dissolved organic C (DOC) and microbial biomass C (MBC) contents were measured in this study. Soil TOC and labile organic C fractions contents were significantly affected by straw returns, and were higher under straw return treatments than non-straw return at three depths. At 0–7 cm depth, soil MBC was significantly higher under plowing tillage than rotary tillage, but EOC was just opposite. Rotary tillage had significantly higher soil TOC than plowing tillage at 7–14 cm depth. However, at 14–21 cm depth, TOC, DOC and MBC were significantly higher under plowing tillage than rotary tillage except for EOC. Consequently, under short-term condition, rice and wheat straw both return in rice-wheat rotation system could increase SOC content and improve soil quality in the Yangtze River Delta. PMID:24586434

  1. Description of two new species of the Exocelina broschii-group from Papua New Guinea, with revision and key to all representatives of this species group (Coleoptera, Dytiscidae, Copelatinae)

    PubMed Central

    Shaverdo, Helena; Sagata, Katayo; Balke, Michael

    2016-01-01

    Abstract Two new species of Exocelina Broun, 1886 from Papua New Guinea are described herein: Exocelina mondmillensis sp. n. and Exocelina pseudomarinae sp. n. They are placed into the Exocelina broschii-group based on the shovel/fork-like ventral sclerites of their median lobe. While the former has rather distinct combination of the morphological characters (inconspicuous dorsal punctation, thin apex of the median lobe and ventral sclerite of the median lobe with two tips of different length), the latter is very similar to already described species Exocelina marinae (Shaverdo, Sagata & Balke, 2005). All described species of the group are revised and a key to their identification is provided. Important diagnostic characters (habitus, color, protarsomeres 4–5, median lobes, and parameres) are illustrated. Data on the distribution of all species of the group are given showing that its representatives occur only in Papua New Guinea and most of them are widely distributed in it central part. PMID:27110191

  2. Waterfowl ecology and avian influenza in California: do host traits inform us about viral occurrence?

    PubMed

    Hill, Nichola J; Takekawa, John Y; Cardona, Carol J; Ackerman, Joshua T; Schultz, Annie K; Spragens, Kyle A; Boyce, Walter M

    2010-03-01

    We examined whether host traits influenced the occurrence of avian influenza virus (AIV) in Anatidae (ducks, geese, swans) at wintering sites in California's Central Valley. In total, 3487 individuals were sampled at Sacramento National Wildlife Refuge and Conaway Ranch Duck Club during the hunting season of 2007-08. Of the 19 Anatidae species sampled, prevalence was highest in the northern shoveler (5.09%), followed by the ring-necked duck (2.63%), American wigeon (2.57%), bufflehead (2.50%), greater white-fronted goose (2.44%), and cinnamon teal (1.72%). Among host traits, density of lamellae (filtering plates) of dabbling ducks was significantly associated with AIV prevalence and the number of subtypes shed by the host, suggesting that feeding methods may influence exposure to viral particles. PMID:20521673

  3. Backcountry snowmobilers' risk perceptions, avalanche related information seeking behaviours, preparedness and decision-making processes

    NASA Astrophysics Data System (ADS)

    Baker, Jennifer

    Although there has been substantial research on the avoidance of risk, much less has been completed on voluntary risk. This study examined backcountry snowmobilers' risk perceptions, avalanche related information seeking behaviours, and decision-making processes when dealing with avalanches and backcountry risk in Canada. To accomplish this, in-depth, semi-structured interviews were conducted with 17 participants who were involved in backcountry snowmobiling. Interviews were done both in person and by telephone. The results of this study show that, unlike previous research on snowmobilers, the participants of this study were well prepared and knowledgeable about backcountry risks. All 17 participants stated that they carried a shovel, probe, and transceiver with them on each backcountry trip, and 10 participants had taken an avalanche safety course. Group dynamics and positive peer pressure were influential in promoting safe backcountry behaviour. KEYWORDS: Backcountry snowmobiling, Avalanches, Voluntary Risk, Preparedness, Decision-Making.

  4. T-Rex system for operation in TRU, LLW, and hazardous zones. Transuranic storage area-retrieval enclosure program

    SciTech Connect

    Kline, H.M.; Andreychek, T.P.; Beeson, B.K.

    1993-04-01

    There are a large number of sites around the world containing TRU (transuranic) waste, low level waste (LLW), and hazardous areas that require teleoperated, heavy lift manipulators with long reach and high precision to handle the materials stored there. Teleoperation of the equipment is required to reduce the risk to operating personnel to as-low-as-reasonably-achievable (ALARA) levels. The Transuranic Storage Area Remote Excavator system (T-Rex) is designed to fill this requirement at low cost through the integration of a production front shovel excavator with a control system, local and remote operator control stations, a closed-circuit television system (CCTV), multiple end effectors and a quick-change system. This paper describes the conversion of an off-the-shelf excavator with a hydraulic control system, the integration of an onboard remote control system, vision system, and the design of a remote control station.

  5. T-Rex system for operation in TRU, LLW, and hazardous zones

    SciTech Connect

    Kline, H.M. ); Andreychek, T.P.; Beeson, B.K. . Aero and Naval Systems)

    1993-01-01

    There are a large number of sites around the world containing TRU (transuranic) waste, low level waste (LLW), and hazardous areas that require teleoperated, heavy lift manipulators with long reach and high precision to handle the materials stored there. Teleoperation of the equipment is required to reduce the risk to operating personnel to as-low-as-reasonably-achievable (ALARA) levels. The Transuranic Storage Area Remote Excavator system (T-Rex) is designed to fill this requirement at low cost through the integration of a production front shovel excavator with a control system, local and remote operator control stations, a closed-circuit television system (CCTV), multiple end effectors and a quick-change system. This paper describes the conversion of an off-the-shelf excavator with a hydraulic control system, the integration of an onboard remote control system, vision system, and the design of a remote control station.

  6. Later Middle Pleistocene human remains from the Almonda Karstic system, Torres Novas, Portugal.

    PubMed

    Trinkaus, Erik; Marks, Anthony E; Brugal, Jean Philip; Bailey, Shara E; Rink, W Jack; Richter, Daniel

    2003-09-01

    Later Middle Pleistocene archeological deposits of the Galeria Pesada (Gruta da Aroeira), Almonda Karstic System, Torres Novas, Portugal, yielded two archaic human teeth, a mandibular canine and a maxillary third molar. The C(1)presents moderate and asymmetrical shoveling with a stout root. The slightly worn M(3)exhibits at least four cusps with a large hypocone, three roots with large radicular plates, and an absence of taurodontism. They are moderately large for later Middle Pleistocene humans in their buccolingual crown diameters, although the M(3)mesiodistal diameter is modest. The C(1)exhibits labial calculus and multiple linear hypoplastic defects, but the M(3)is lesion free. Both teeth are morphologically similar to those of other Middle Pleistocene European humans and reinforce a pattern of dental hypertrophy among these archaic Homo. PMID:14580591

  7. Noise exposure profile among heavy equipment operators, associated laborers, and crane operators.

    PubMed

    Legris, M; Poulin, P

    1998-11-01

    This study, conducted in 1987 and 1988, has made it possible to quantify exposure to noise among heavy equipment operators, associated laborers, and crane operators. The average daily noise exposure was 84 to 99 dBA for heavy equipment, 90 dBA for the laborer, and 74 to 97 dBA for the crane operator. The main sources of noise to which heavy equipment operators are exposed are vehicle engines and the muffler exhaust system, usually located near the operator. The presence of insulated cabs such as those found on power shovels, backhoes, wheel loaders, and graders help reduce noise exposure. The type of tasks carried out by the laborers, the sources of noise from heavy equipment around which they work, and the manual equipment they use determine the noise levels to which such workers are exposed. In the case of crane operators, an insulated cab significantly reduces the operator's exposure to engine noise. PMID:9830084

  8. Impacts of changing irrigation practices on waterfowl habitat use in the southern San Joaquin Valley, California

    USGS Publications Warehouse

    Barnum, D.A.; Euliss, N. H ., Jr.

    1991-01-01

    We used diurnal aerial census data to examine habitat use patterns of ducks wintering in the southern San Joaquin Valley, California from 1980-87. We calculated densities (birds/ha) for the northern pintail (Anas acuta), mallard (A. platyrhynchos), green-winged teal (A. crecca), cinnamon teal (A. cyanoptera), shoveler (A. clypeata), ruddy duck (Oxyura jamaicensis), and total ducks in each of 5 habitats. Densities of pintail and total ducks were greater in September than in other months. From October through January, density of teal and total ducks was greatest on Kern National Wildlife Refuge (NWR). Densities of ruddy duck and pintail were greatest on agricultural drainwater evaporation ponds and preirrigated cropland, respectively.

  9. Selection of operating machinery parameters for a bucket excavator

    SciTech Connect

    Fabrichnyi, Y.F.; Baboshin, K.V.; Etinger, I.M.; Mekk, V.A.

    1985-05-01

    The mining industry uses extensively single-bucket excavators of the straight shovel type, like the EKG-4.6, as the most effective way of loading previously loosened hard and abrasive excavated rocks. Therefore, an increase in their working efficiency, mainly as regards increasing productivity, reducing load on the operating machinery, and reducing wear of the operating machinery elements, is of particular importance. Analysis shows that the possibilities for this lie in the correct selection of movement trajectory parameters for the excavator bucket, which for existing excavators are inadequate for loading excavated rock. The authors study here the effect of trajectory parameters on excavator bucket filling, and on their basis they select parameters for the operating machinery.

  10. Mining in low coal. Volume 1. Biomechanics and work physiology. Open file report 15 Jun 78-15 Sep 81

    SciTech Connect

    Ayoub, M.M.; Bethea, N.J.; Bobo, M.; Burford, C.L.; Caddel, D.K.

    1981-11-01

    The objectives of this research were (1) to evaluate the job demands associated with low coal mining, (2) to survey the anthropometry, strength, and aerobic capacity of low coal miners to determine if they differ from the U.S. population, and (3) to recommend, on the basis of available information, optimal job and work station design for low coal mining. The male and female anthropometry, except for weight and circumferential dimensions, was quite similar to the comparison populations. Back strength for male and female miners was significantly lower than the industrial worker population. This can be one of the contributing factors of low back problems in mining. Shoveling, timbering, and helpers tasks were physiologically demanding activities. However, because of the frequent stoppage of work, adequate rest was usually available. If work stoppage is corrected, then better work and rest schedules are essential.

  11. Study of Internal Dump Stability of Dudhichua Open Cast Project, Northern Coalfields Limited, India

    NASA Astrophysics Data System (ADS)

    Sengupta, S.; Roy, I.

    2015-04-01

    Dudhichua Open Cast Project is one of the prestigious projects of Northern Coalfields Limited, India; with total mineable coal reserves of approximately 400 million tonnes and corresponding 1,700 million m3 volume of waste rock i.e. overburden material. Accommodating this waste dump masses in the limited space of the de-coaled portion of the quarry is considered as one of the major challenges to the mine operators. It has been reported that this mine is facing frequent slope failures of waste rock dumps which is of great concern to the mine management in view of unsafe working condition. To tackle the above problem, a detailed investigation was carried out to propose a stable dump profile which will cater to the land economics and safety aspects of the mine. A detailed investigation along with recommendation of optimum design for dragline dump profile along with shovel-dumper-dump profile is presented in this paper.

  12. Stone tool production and utilization by bonobo-chimpanzees (Pan paniscus).

    PubMed

    Roffman, Itai; Savage-Rumbaugh, Sue; Rubert-Pugh, Elizabeth; Ronen, Avraham; Nevo, Eviatar

    2012-09-01

    Using direct percussion, language-competent bonobo-chimpanzees Kanzi and Pan-Banisha produced a significantly wider variety of flint tool types than hitherto reported, and used them task-specifically to break wooden logs or to dig underground for food retrieval. For log breaking, small flakes were rotated drill-like or used as scrapers, whereas thick cortical flakes were used as axes or wedges, leaving consistent wear patterns along the glued slits, the weakest areas of the log. For digging underground, a variety of modified stone tools, as well as unmodified flint nodules, were used as shovels. Such tool production and utilization competencies reported here in Pan indicate that present-day Pan exhibits Homo-like technological competencies. PMID:22912400

  13. Dental anthropology of a Brazilian sample: Frequency of nonmetric traits.

    PubMed

    Tinoco, Rachel Lima Ribeiro; Lima, Laíse Nascimento Correia; Delwing, Fábio; Francesquini, Luiz; Daruge, Eduardo

    2016-01-01

    Dental elements are valuable tools in a study of ancient populations and species, and key-features for human identification; among the dental anthropology field, nonmetric traits, standardized by ASUDAS, are closely related to ancestry. This study aimed to analyze the frequency of six nonmetric traits in a sample from Southeast Brazil, composed by 130 dental casts from individuals aged between 18 and 30, without foreign parents or grandparents. A single examiner observed the presence or absence of shoveling, Carabelli's cusp, fifth cusp, 3-cusped UM2, sixth cusp, and 4-cusped LM2. The frequencies obtained were different from the ones shown by other researches to Amerindian and South American samples, and related to European and sub-Saharan frequencies, showing the influence of this groups in the current Brazilian population. Sexual dimorphism was found in the frequencies of Carabelli's cusp, 3-cusped UM2, and sixth cusp. PMID:26628292

  14. Grassland birds orient nests relative to nearby vegetation

    USGS Publications Warehouse

    Hoekman, S.T.; Ball, I.J.; Fondell, T.E.

    2002-01-01

    We studied orientation of nest sites relative to nearby vegetation for dabbling ducks (Cinnamon Teal, Anas cyanoptera; Blue-winged Teal, A. discors; Gadwall, A. strepera; Mallard, A. platyrhynchos; and Northern Shoveler, A. clypeata) and Short-eared Owls (Asio flammeus) in ungrazed grassland habitat during 1995-1997 in westcentral Montana. We estimated an index of vegetation height and density in intercardinal directions (NE, SE, SW, NW) immediately around nests. All species oriented nests with the least vegetation to the southeast and the most vegetation to either the southwest or northwest. Furthermore, maximum vegetation around nests shifted from the southwest to the northwest with increasing nest initiation date, apparently as a response of individuals tracking seasonal change in the afternoon solar path. Thus, nests were relatively exposed to solar insolation during cool morning hours but were shaded from intense insolation in the afternoon throughout the breeding season. We suggest that nest microhabitat was selected in part to moderate the thermal environment.

  15. The economic-impact fallacy

    NASA Astrophysics Data System (ADS)

    Moriarty, Philip

    2009-06-01

    Before the UK budget was announced in April, there had been excited expectations of an "Obama-style" £1bn stimulus package for science. That prospect prompted research councils and learned societies in the UK to rush to identify "shovel-ready" projects that could benefit from a fresh injection of funds. However, their efforts were in vain - the stimulus did not arrive. Instead, John Denham, secretary of state for Innovation, Universities and Skills, has had to put a brave face on an immensely disappointing budget settlement for science. The Department for Innovation, Universities and Skills (DIUS), which Denham runs, must now make £0.5bn in savings over the next two years.

  16. Waterfowl ecology and avian influenza in california: Do host traits inform us about viral occurrence?

    USGS Publications Warehouse

    Hill, N.J.; Takekawa, J.Y.; Cardona, C.J.; Ackerman, J.T.; Schultz, A.K.; Spragens, K.A.; Boyce, W.M.

    2010-01-01

    We examined whether host traits influenced the occurrence of avian influenza virus (AIV) in Anatidae (ducks, geese, swans) at wintering sites in California's Central Valley. In total, 3487 individuals were sampled at Sacramento National Wildlife Refuge and Conaway Ranch Duck Club during the hunting season of 2007-08. Of the 19 Anatidae species sampled, prevalence was highest in the northern shoveler (5.09%), followed by the ring-necked duck (2.63%), American wigeon (2.57%), bufflehead (2.50%), greater white-fronted goose (2.44%), and cinnamon teal (1.72%). Among host traits, density of lamellae (filtering plates) of dabbling ducks was significantly associated with AIV prevalence and the number of subtypes shed by the host, suggesting that feeding methods may influence exposure to viral particles. ?? 2010 American Association of Avian Pathologists.

  17. Waterfowl density on agricultural fields managed to retain water in winter

    USGS Publications Warehouse

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

    1999-01-01

    Managed water on private and public land provides habitat for wintering waterfowl in the Mississippi Valley, where flood control projects have reduced the area of natural flooding. We compared waterfowl densities on rice, soybean, and moist-soil fields under cooperative agreements to retain water from 1 November through 28 February in Arkansas and Mississippi and assessed temporal changes in waterfowl density during winter in 1991-1992 and 1992-1993. Fields flooded earlier in Arkansas, but retained water later in Mississippi. Over winter, waterfowl densities decreased in Arkansas and increased in Mississippi. Densities of waterfowl, including mallard (Anas platyrhynchos), the most abundant species observed, were greatest on moist-soil fields. However, soybean fields had the greatest densities of northern shoveler (Spatula clypeata).

  18. The use of high density ammonium nitrate mini-prill blasting agents to reduce drilling and blasting costs

    SciTech Connect

    Adams, J.C.; Irwin, R.

    1994-12-31

    In early 1993 a test program was designed to determine if mining costs could be reduced by using a high density ammonium nitrate mini-prill blasting agent. The goal was to reduce mining costs by expanding blast hole patterns while maintaining or improving dig-ability of the shot material. The results of the program indicated that with the high density ammonium nitrate blasting agent, fragmentation of the waste rock could be maintained or improved while expanding blast patterns by 23%. When used within ore zone boundaries, where pattern expansion and material displacement is not desirable, an improvement in shovel productivity was recognized while no increase in ore dilution was experienced. A reduction in bucket tooth wear was also reported.

  19. KSC-03PD-0578

    NASA Technical Reports Server (NTRS)

    2003-01-01

    KENNEDY SPACE CENTER, FLA. -- -- Lifting their shovels for the groundbreaking of the Operations Support Building II are (left to right) Bill Pickavance, Vice President & Deputy Program Manager Florida Operations, United Space Alliance; Mike Wetmore, director of Shuttle Processing; Miguel Morales, chief, Facilities Division, Spaceport Services; Mike Sumner, chief of operations, Spaceport Services; David Wolfberg, designer of the facility, with Architect and Engineers Wolfberg, Alvarez and Partners of Coral Gables; Roy Bridges, KSC director; and Don Minderman, OSB II project manager, Spaceport Services. Not shown: David Boland, David Boland Inc.(construction company). The new building will replace modular housing constructed more than 20 years ago and house NASA and contractor support staff for shuttle operations. The demolition of the modular buildings has begun and construction will immediately follow. The new structure is projected to be ready in April 2005.

  20. Stone tool production and utilization by bonobo-chimpanzees (Pan paniscus)

    PubMed Central

    Roffman, Itai; Savage-Rumbaugh, Sue; Rubert-Pugh, Elizabeth; Ronen, Avraham; Nevo, Eviatar

    2012-01-01

    Using direct percussion, language-competent bonobo-chimpanzees Kanzi and Pan-Banisha produced a significantly wider variety of flint tool types than hitherto reported, and used them task-specifically to break wooden logs or to dig underground for food retrieval. For log breaking, small flakes were rotated drill-like or used as scrapers, whereas thick cortical flakes were used as axes or wedges, leaving consistent wear patterns along the glued slits, the weakest areas of the log. For digging underground, a variety of modified stone tools, as well as unmodified flint nodules, were used as shovels. Such tool production and utilization competencies reported here in Pan indicate that present-day Pan exhibits Homo-like technological competencies. PMID:22912400

  1. Revealing the Hidden Value that the Federal Investment Tax Credit and Treasury Cash Grant Provide To Community Wind Projects

    SciTech Connect

    Bolinger, Mark A.

    2009-12-14

    Although the global financial crisis of 2008/2009 has slowed wind power development in general, the crisis has, in several respects, been a blessing in disguise for community wind project development in the United States. For xample, the crisis-induced slowdown in the broader commercial wind market has, for the first time since 2004, created slack in the supply chain, creating an opportunity for shovel-ready community wind projects to finally proceed towards onstruction. Many such projects had been forced to wait on the sidelines as the commercial wind boom of 2005-2008 consumed virtually all available resources needed to complete a wind project (e.g., turbines, cranes, contractors).

  2. Foot preferences during resting in wildfowl and waders.

    PubMed

    Randler, Christoph

    2007-03-01

    Footedness in birds has been reported, e.g., in parrots and chickens, but the direction of footedness remained unclear. Is a bird left-footed because it uses its left foot for holding and handling food, or is it right-footed because it uses the right foot for stabilisation and balancing while perching? In 2004 and 2006 I examined footedness in wildfowl and waders while the birds were performing a single task: roosting on the ground on one foot. Avocet (Recurvirostra avosetta), northern shoveller (Anas clypeata), oystercatcher (Haematopus ostralegus), and Eurasian curlew (Numenius arquata) were right-footed. Another 21 species did not show any significant foot preferences. This study provides some evidence that asymmetries in preferential foot use in birds may be triggered by a preference during postural control. PMID:17365634

  3. Avian influenza in wild waterfowl and shorebirds in the Donana National Park: Serological survey using the enzyme-linked immunosorbent assay.

    PubMed

    Astorga, R J; Leon, L; Cubero, M J; Arenas, A; Maldonado, A; Tarradas, M C; Perea, A

    1994-06-01

    The indirect ELISA was used to detect antibodies to influenzavirus A in the sera of wildfowl from the Donana National Park. Of the 712 birds examined, 44 (6.2%) were seropositive. Positive birds belonged to 10 of the 13 species studied. Infection rates varied widely: spoonbill (Platalea leucorodia, 32.2%), mallard (Anas platyrhynchos, 9.9%), gadwall (Anas strepera, 8.6%), red-crested pochard (Netta rufina, 8.1%), pochard (Aythya ferina, 6.4%), shoveler (Anas clypeata, 5%), great crested grebe (Podiceps cristatus, 4.3%), avocet (Recurvirostra avosetta, 3.1%), grey heron (Ardea cinerea, 3.1%) and coot (Fulica atra, 0.8%). Although infection rates were not high, the wide range of avian species susceptible to influenzavirus A suggests circulation of the virus amongst wildfowl at Donana. PMID:18671098

  4. Dust control for draglines

    SciTech Connect

    Grad, P.

    2009-09-15

    Monitoring dust levels inside draglines reveals room for improvement in how filtration systems are used and maintained. The Australian firm BMT conducted a field test program to measure airflow parameters, dust fallout rates and dust concentrations, inside and outside the machine house, on four draglines and one shovel. The study involved computational fluid dynamics (CFD) simulations. The article describes how the tests were made and gives results. It was not possible to say which of the two main filtration systems currently used on Australian draglines - Dynavane or Floseps - performs better. It would appear that more frequent maintenance and cleaning would increase the overall filtration performance and systems could be susceptible to repeat clogging in a short time. 2 figs., 1 photos.

  5. [Chromatography analysis of tobacco smoke condensate in biology tissue].

    PubMed

    Zurabashvili, D Z; Chanturia, I R; Kapanadze, L R

    2010-01-01

    Specialized analytical instrumentation for detailed analysis of nicotine, benz(alpha)pyrene, pyridine and benzene in tooth enamel and pulp of inveterate tobacco smokers is created. A Waters PPY-24 liquid chromatograph is equipped with Model M660 solvent programmer and a Model U6K sample injector is used. A Model 440 dual-wavelength detector is used to obtain absorbance ratios on dual-pen recorder. Our data show that concentration of tobacco smoke components in tooth cavity of inveterate tobacco smokers is different. The chisel tooth pulp contained considerably more nicotine and pyridine as compared with molars. The level of benzene does not change analyzed structures. The assumption of linearity between calculation of predicted retention times and concentration has been shown to be valid up to about 8,0% for all studied compounds. PMID:20157203

  6. Surgical resection and prosthetic treatment of an extensive mandibular torus.

    PubMed

    Goncalves, Thais Marques Simek Vega; de Oliveira, Jonas Alves; Sanchez-Ayala, Alfonso; Rodrigues Garcia, Renata Cunha Matheus

    2013-01-01

    The aim of this case report was to describe the surgical removal of an extensive mandibular torus and the conventional prosthetic treatment that was performed. During surgery, the torus was exposed by a intrasulcular lingual incision from molar to contralateral molar side and displacement of the mucoperiosteal flap. The bone volume was carefully removed in three separate blocks by sculpting a groove in the superior lesion area and chiseling. After a 30-day postoperative period, a prosthetic treatment was performed using a conventional distal extension removable partial denture. The patient's esthetic and functional expectations were achieved. The surgical procedure and prosthetic treatment performed in the treatment of the mandibular torus in this clinical case is a viable treatment that produces few complications and re-establishes normal masticatory function. PMID:23302351

  7. So I Sat Down with My Mother: Connectedness Orientation and Pupils' Independence

    NASA Astrophysics Data System (ADS)

    Eklöf, Anders; Nilsson, Lars-Erik; Svensson, Peter

    Swedish educational policy underlines the importance of independence. In this paper we use socio-cultural theory and Foucault to explain how pupils’ independency is transformed into something else in their work. Our results derive from analyses of filmed sessions and entries in the pupils’ logbooks. Our findings demonstrate that the pupils’ definitions of independence differ from those of the course plan in several aspects: i) the use of certain resources is not considered to show lack of independence, ii) doing things yourself is considered being most independent and iii) to follow instructions, even if this means violating your unique personal thought, is considered a prerequisite for passing/getting good grades and as such a necessary adaption to the school context, sooner than a sign of dependency. Consequently we argue that pupil independency should be regarded as a phenomenon chiseled out within a community of practice rather than a personal capacity.

  8. Were Viking Dry-dock methods in the Americas used earlier to Build Pyramids, with Outflow Eroding the Sphinx, and were Stonehenge, the Obelisks, and Moas Similarly Erected?

    NASA Astrophysics Data System (ADS)

    McLeod, Edward; McLeod, Roger

    2006-03-01

    Chisel-quarried recycled granite in MA is datable by runes to 1069 CE; it could corroborate dating by a LIDAR. Associated sites, possibly used by Vikings to dry-dock their ships, could have exploited lock-like controls, possibly a continued technology. Site-leveling at the Giza Pyramids proves water was used. `Locks' and body-immersion worked for building, moving, erecting, or watering, at sites like Stonehenge, The Hanging Gardens at Babylon, the Moas of Easter Island, or The Pyramids, where the eroding water discharge was deliberately flushed over the Sphinx complex. It enhance the electromagnetically excited blue light signals we can detect, especially at sites frequented by Molocket of ME. Information, as at America's Stonehenge, in NH, and constructions at Acton MA, at Giza or at Rumford ME proves that the Pyramids and Sphinx were engineered and built about 4500 BP.

  9. Observation of Nonspreading Wave Packets in an Imaginary Potential

    SciTech Connect

    Stuetzle, R.; Goebel, M.C.; Hoerner, Th.; Kierig, E.; Mourachko, I.; Oberthaler, M.K.; Efremov, M.A.; Fedorov, M.V.; Yakovlev, V.P.; Leeuwen, K.A.H. van; Schleich, W.P.

    2005-09-09

    We propose and experimentally demonstrate a method to prepare a nonspreading atomic wave packet. Our technique relies on a spatially modulated absorption constantly chiseling away from an initially broad de Broglie wave. The resulting contraction is balanced by dispersion due to Heisenberg's uncertainty principle. This quantum evolution results in the formation of a nonspreading wave packet of Gaussian form with a spatially quadratic phase. Experimentally, we confirm these predictions by observing the evolution of the momentum distribution. Moreover, by employing interferometric techniques, we measure the predicted quadratic phase across the wave packet. Nonspreading wave packets of this kind also exist in two space dimensions and we can control their amplitude and phase using optical elements.

  10. Two new paratanaid Tanaidacea (Crustacea: Malacostraca: Peracarida) from the Hawaiian Islands, with illustrated taxonomic keys.

    PubMed

    Morales-Núñez, Andrés G; Pelleteri, Sara; Heard, Richard W

    2016-01-01

    Two new tanaidomorphan tanaidaceans, Aparatanais hawaiensis, sp. nov. and Metatanais spinipropodus, sp. nov. represent the first members of the Family Paratanaidae to be described from the Hawaiian Islands. Aparatanais hawaiensis is distinguished from the other species of the genus by the setation of the antenna, maxilliped, chela, and pereopods. Metatanais spinipropodus is distinguished from the other three members of its genus by its chela having a strongly developed, chisel-like, spiniform seta on the inner face of propodus near the sub-distal margin of the fixed finger. The Hawaiian occurrence of M. spinipropodus extends the range for the genus Metatanais well-eastward into the mid-Pacific Ocean. This study presents the first description of a male attributable to the genus Aparatanais. PMID:27615684

  11. Soap-stone in architecture of North European cities. A nomination as a candidate for a Global Heritage Stones Resource

    NASA Astrophysics Data System (ADS)

    Bulakh, Andrey

    2016-04-01

    Soap stone represents soft Proterozoic rock type from the deposit Nunnalahti situated on the western shore of the big Lake Pielinen in Eastern Finland. It consists of talc (40 - 50 %), magnesite MgCO3 (40 - 50 %), chlorite (5 - 8 %), dolomite, calcite, etc. The colour of the stone is very spectacular and varies from yellow and brownish-yellow to grey, greenish grey. The soft stone is a highly workable material for a sculptor's chisel. It was one of the most popular ornamental rocks used architecture of the Modern style in St Petersburg, Helsinki, Turku, Tampere and other North European cities lately in the XIX-th centuries. Examples are given and discussed. References: Bulakh, A.G., Abakumova, N.B., and Romanovsky, J.V. St Petersburg: a History in Stone. 2010. Print House of St Petersburg State University. 173 p. (In English).

  12. A balsa violin

    NASA Astrophysics Data System (ADS)

    Waltham, Chris

    2009-01-01

    Almost half a century ago John Schelleng determined the scaling rules that show how violins can be made from nontraditional materials. These principles suggest that balsa wood may be a possible, if unlikely, construction material. To test this idea, a balsa violin was constructed and found to be playable. Its vibrational behavior is shown to be in agreement with Schelleng's scaling rules. The instrument was not difficult to build, and its construction can be repeated by anyone of moderate skill with a chisel and sandpaper and access to an audio frequency analysis program. The reward is a tactile appreciation for the vibrational behavior of materials and the physics of musical instruments that is difficult to gain otherwise.

  13. [Animal experiments on cementing small osteochondral fragments with fibrin glue].

    PubMed

    Zilch, H

    1980-01-01

    An experiment on revascularization of glued osteochondral fragments was carried out. A chiseled part of the medial femoral condyle of the knee joint of the rabbit was fixed on the right side with an acryl adhesive and on the left side with a new fibrinogen adhesive system (FAS), consisting of highly concentrated fibrinogen, thrombin, and factor XIII. The animals were sacrificed after three, six, ten, and twenty eight days. The FAS is changed into granulation tissue rich in vessels and, therefore, there is a quick revascularization of the fragments soon after three days. On the contrary the acryl adhesive is a foreign body and prevents ingrowth of capillaries during the time of investigation. Immobilization with plaster is necessary to prevent the fragment from gliding off. PMID:6972890

  14. Applications of ERTS-1 data to landscape change in eastern Tennessee

    NASA Technical Reports Server (NTRS)

    Rehder, J. B. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. The analysis of landscape change in eastern Tennessee from ERTS-1 data is being derived from three avenues of experimentation and analysis: (1) a multi-stage sampling procedure utilizing ground and aircraft imagery for ground truth and control; (2) a densitometric and computer analytical experiment for the analysis of gray tone signatures and comparisons for landscape change detection and monitoring; and (3) an ERTS image enhancement procedure for the detection and analysis of photomorphic regions. Significant results include: maps of strip mining changes and forest inventory, watershed identification and delimitation, and agricultural regions derived from spring plowing patterns appearing on the ERTS-1 imagery.

  15. Self-revegetation of disturbed ground in the deserts of Nevada and Washington

    SciTech Connect

    Rickard, W.H.; Sauer, R.H.

    1982-01-01

    Plant cover established without purposeful soil preparation or seeding was measured on ground disturbed by plowing in Washington and by aboveground nuclear explosions in Nevada. After a time lapse of three decades in Washington and two decades in Nevada, fewer species were self-established on the disturbed ground than the nearby undisturbed ground. Alien annual plants were the dominants on the disturbed ground. Cheatgrass (Bromus tectorum) dominated abandoned fields in Washington, and filaree (Erodium cicutarium) dominated disturbed ground in Nevada. Perennial grasses and shrubs appeared to be more successful as invaders in Nevada than in Washington. This distinction is attributed to the superior competitive ability of cheatgrass in Washington.

  16. Chemical potential fluctuations in topological insulator (Bi0.5Sb0.5)2Te3-films visualized by photocurrent spectroscopy

    NASA Astrophysics Data System (ADS)

    Kastl, Christoph; Seifert, Paul; He, Xiaoyue; Wu, Kehui; Li, Yongqing; Holleitner, Alexander

    2015-06-01

    We investigate the photocurrent properties of the topological insulator (Bi0.5Sb0.5)2Te3 on SrTiO3-substrates. We find reproducible, submicron photocurrent patterns generated by long-range chemical potential fluctuations, occurring predominantly at the topological insulator/substrate interface. We fabricate nano-plowed constrictions which comprise single potential fluctuations. Hereby, we can quantify the magnitude of the disorder potential to be in the meV range. The results further suggest a dominating photo-thermoelectric current generated in the surface states in such nanoscale constrictions.

  17. Friction and wear of metals with a single-crystal abrasive grit of silicon carbide: Effect of shear strength of metal

    NASA Technical Reports Server (NTRS)

    Miyoshi, K.; Buckley, D. H.

    1978-01-01

    Sliding friction experiments were conducted with spherical, single-crystal silicon carbide riders in contact with various metals and with metal riders in contact with silicon carbide flats. Results indicate that: (1) the friction force in the plowing of metal and (2) the groove height (corresponding to the volume of the groove) are related to the shear strength of the metal. That is, they decrease linearly as the shear strength of the bulk metal increases. Grooves are formed in metals primarily from plastic deformation, with occasional metal removal. The relation between the groove width D and the load W can be expressed by W = kD, superscript n which satisfies Meyer's law.

  18. AmeriFlux US-LPH Little Prospect Hill

    SciTech Connect

    Hadley, Julian

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-LPH Little Prospect Hill. Site Description - The site was cleared for pasture, but not deeply plowed or planted, in the 18th and 19th centuries. Agriculture on the site was abandoned near the end of the 19th century. The forest within 200 to 300 m of the eddy covariance tower to the NW, W, SW, and S burned in an intense fire in 1957, which left few or no surviving trees.

  19. AmeriFlux US-Ced Cedar Bridge

    DOE Data Explorer

    Clark, Ken [USDA Forest Service

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ced Cedar Bridge. Site Description - Wildfires and prescribed fires are a common occurrence in the NJ Pinelands. Prior to a 1995 nonstand replacing wildfire, the stand was last burned in the very large wildfire in 1963. Plow lines were installed for fire control in December of 2007, followed by a prescribed burns in 2008 and 2013, conducted by the New Jersey Forest Fire Service. Pine looper defoliated the stand in 1998, and Gypsy moth defoliated the understory and deciduos oaks in 2007. Pitch Pines are largely unaffected by defoliation by Gypsy moth.

  20. Prediction of soil loss with the CREAMS model

    SciTech Connect

    Becker, N.M.

    1984-07-24

    Variations in soil loss as a function of certain land use and land management practices were investigated on a small watershed in the Texas Panhandle using CREAMS, a recently developed computer model capable of simulating dynamic rainfall, runoff, and erosion processes over the time-frame of decades. Simulations of different curve numbers, three types of cropping, and varying crop yield and plowing practices were made to determine the sensitivity of soil loss to these parameters. Comparisons were made to actual in-field measurements of soil loss on experimental plots. 8 references, 3 figures.

  1. Black soldier fly (Diptera: Stratiomyidae) colonization of pig carrion in south Georgia.

    PubMed

    Tomberlin, Jeffery K; Sheppard, D Craig; Joyce, John A

    2005-01-01

    The black soldier fly, Hermetia illucens (L.), is thought to colonize corpses 20-30 days postmortem. However, recent observations indicate this might not be true for all cases. Therefore, we conducted a study examining colonization by the black soldier fly and other Diptera on pig carrion in a plowed field in southern Georgia from 20 September through 21 February. Our data indicate black soldier flies could colonize a corpse within the first week after death. Knowing this information could prevent a serious mistake in estimating the time at which a corpse is colonized by this species. This study also represents the first record of Chrysomya rufifacies in Georgia. PMID:15831010

  2. 29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Plow Steel Grade Rope With Fiber Core (FC) , tons (2,000 lb)] Vertical Rope diameter, inch HT MS S Choker HT, MS&S 1/4 0.49 0.51 0.55 0.38 5/16 0.78 0.79 0.85 0.6 3/8 1.1 1.1 1.2 0.85 7/16 1.4 1.5 1.7 1.2... in HT (FC) columns. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1) These...

  3. Ground control failures. A pictorial view of case studies

    SciTech Connect

    Peng, S.S.

    2007-07-01

    The book shows, in pictorial views, many forms and/or stages of types of failures in mines, for instance, cutter, roof falls, and cribs. In each case, the year of occurrence is stated in the beginning so that the environment or technological background under which it occurred are reflected. The narrative than begins with the mining and geological conditions, followed by a description of the ground control problems and recommended solutions and results, if any. The sections cover failure of pillars, roof falls, longwall, roof bolting, multiple-seam mining, floor heave, longwall, flooding and weathering of coal, old workings, and shortwall and thin-seam plow longwall.

  4. Experimental Study of Implosion Dynamics of Multi-Shell Z-Pinches at Microsecond Implosion Times

    NASA Astrophysics Data System (ADS)

    Shishlov, Alexander V.; Chaikovsky, Stanislav A.; Fedunin, Anatoly V.; Fursov, Fedor I.; Kokshenev, Vladimir A.; Kurmaev, Nikolai E.; Labetsky, Aleksey Yu.; Oreshkin, Vladimir I.; Rousskikh, Alexander G.; Zhidkova, Natalia A.

    2006-01-01

    A set of experiments has been conducted on the GIT-12 generator (4.7 MA, 1.7 μs) operating at microsecond mode. The experiments were carried out with multi-shell gas puffs. Dynamics of current-carrying plasma was registered by a set of B-dots monitors placed at different radii inside a multi-shell gas puff. The experimental data obtained with the help of B-dots monitors are compared with 0D snow-plow simulations of implosion dynamics and discussed taking into consideration the data from other Z-pinch diagnostics.

  5. Cropping management using color and color infrared aerial photographs

    NASA Technical Reports Server (NTRS)

    Morgan, K. M.; Morris-Jones, D. R.; Lee, G. B.; Kiefer, R. W.

    1979-01-01

    The Universal Soil Loss Equation (USLE) is a widely accepted tool for erosion prediction and conservation planning. Solving this equation yields the long-term average annual soil loss that can be expected from rill and inter-rill erosion. In this study, manual interpretation of color and color infrared 70 mm photography at the scale of 1:60,000 is used to determine the cropping management factor in the USLE. Accurate information was collected about plowing practices and crop residue cover (unharvested vegetation) for the winter season on agricultural land in Pheasant Branch Creek watershed in Dane County, Wisconsin.

  6. Paddy soil cracks: characteristics and their impact on preferential flow

    NASA Astrophysics Data System (ADS)

    Zhang, Zhongbin; Peng, Xinhua

    2015-04-01

    Paddy soils with harrowing and puddling easily crack under alternate flooding and drying cycles (AFD). These cracks in paddy field may become pathways of preferential flow, improving water infiltration and increasing the pollution risk of groundwater. The objectives of this study were to investigate the 2D and 3D characteristics of soil cracks in paddy fields; and to determine their impacts on preferential flow. Two paddy fields, one cultivated for 20 years (YPF) and the other cultivated for more than 100 years (OPF), were subjected to either alternate flooding and drying (AFD) or continuous flooding (CF) during rice growing season. After the harvest of late rice crop, soil surface cracks were recorded using digital camera; and 3D structure of soil cracks was scanned by computed tomography (CT). The characteristics of 2D and 3D soil cracks were quantified with the aid of image analysis. The influence of soil cracks on preferential flow was characterized by tension infiltrometer, dye tracer and ion breakthrough curve. Our main results in this study were summed up as follows: under AFD condition, for the 2D soil cracks, the YPF presented 10 fold more cracks in quantity but these cracks were finer and more complicated as compared to those generated in the OPF. The results of CT scanning showed that the presence of soil cracks under the AFD increased average macropore length but decreased the number of macropores significantly, and it also changed macropore size distribution and macropore area density distribution with soil depth. The 3D structures of soil cracks were complicated but can be quantified using CT. The depth of soil cracks in young paddy field (7.58 cm) was smaller than that in old paddy field (9.34 cm), but soil cracks in both fields did not reach the plough pan (about 15 cm). Soil cracks significantly increased soil hydraulic conductivity. They serviced as pathways for preferential flow only in plow layer, as evidenced by a large dyed area above plough

  7. Impact of conservation agriculture on harnessing sustainability and building resilience against land degradation in the northern Ethiopian highlands

    NASA Astrophysics Data System (ADS)

    Araya, Tesfay; Cornelis, Wim M.; Govaerts, Bram; Bauer, Hans; Deckers, Jozef; Nyssen, Jan

    2013-04-01

    Conservation Agriculture (CA) aims at improving soil quality and crop yield whilst reducing runoff and topsoil erosion which raises the soil resilience to combat soil degradation. Different chemical, physical, and biological properties of a soil interact in complex ways that determine the crop productivity potential of the soil. Hence, a medium-term tillage experiment was carried out (2005 to 2011) on a Vertisol to evaluate changes in soil quality, runoff and soil loss due to CA-based field conservation practices in northern Ethiopia. The experimental layout was implemented in a randomized complete block design with three replications on permanent plots of 5 m by 19 m. The tillage treatments were derdero+ (DER+) with a furrow and permanent raised bed planting system, plowed once at planting by refreshing the furrow and with 30% standing crop residue retention, terwah+ (TER+) with plowing once at planting with 30% standing crop residue retention and contour furrows made at 1.5 m distance interval, and conventional tillage (CT) with a minimum of three tillage operations and removal of crop residues. All the plowing and reshaping of the furrows was done using the local ard plow mahresha. Local crop rotation practices followed during the seven years sequentially from the first to the seventh year included wheat-teff-wheat-barley-wheat-teff-grass pea. Glyphosate was sprayed starting from the third year (2007) at 2 l ha-1 before planting to control pre-emergent weed in DER+ and TER+. Significantly different (p<0.05) mean runoff coefficients (%) in 7-yrs of 13, 20 and 27 were recorded for DER+, TER+ and CT, respectively. Mean soil losses of 7-yrs were 4.4, 12.5 and 18 t ha-1 y-1 in DER+, TER+ and CT, respectively. Among the several assessed soil properties, SOM, N, P, soil microbial biomass carbon, aggregate stability index, consistency index, cone index, air capacity and macroporosity were shown to significantly increase in soils subjected to DER+ planting system

  8. EDARV370A associated facial characteristics in Uyghur population revealing further pleiotropic effects.

    PubMed

    Peng, Qianqian; Li, Jinxi; Tan, Jingze; Yang, Yajun; Zhang, Manfei; Wu, Sijie; Liu, Yu; Zhang, Juan; Qin, Pengfei; Guan, Yaqun; Jiao, Yi; Zhang, Zhaoxia; Sabeti, Pardis C; Tang, Kun; Xu, Shuhua; Jin, Li; Wang, Sijia

    2016-01-01

    An adaptive variant of human Ectodysplasin receptor, EDARV370A, had undergone strong positive selection in East Asia. In mice and humans, EDARV370A was found to affect ectodermal-derived characteristics, including hair thickness, hair shape, active sweat gland density and teeth formation. Facial characteristics are also largely ectodermal derived. In this study, taking advantage of an admixed population of East Asian and European ancestry-the Uyghur, we aim to test whether EDARV370A is affecting facial characteristics and to investigate its pleiotropic nature and genetic model. In a sample of 1027 Uyghurs, we discover that EDARV370A is significantly associated with several facial characteristics, in particular shape of earlobe (P = 3.64 × 10 (-6) ) and type of chin (P = 9.23 × 10 (-5) ), with successful replication in other East Asian populations. Additionally, in this Uyghur population, we replicate previous association findings of incisors shoveling (P = 1.02 × 10 (-7) ), double incisors shoveling (P = 1.86 × 10 (-12) ) and hair straightness (P = 3.99 × 10 (-16) ), providing strong evidence supporting an additive model for the EDARV370A associations. Partial least square path model confirms EDARV370A systematically affect these weakly related ectodermal-derived characteristics, suggesting the pleiotropic effect of EDARV370A mainly plays roles in early embryo development. This study extends our knowledge about the pleiotropic nature of EDARV370A and provides potential clues to its adaptation fitness in human evolution. PMID:26603699

  9. Dust exposure during small-scale mining in Tanzania: a pilot study.

    PubMed

    Bratveit, Magne; Moen, Bente E; Mashalla, Yohana J S; Maalim, Hatua

    2003-04-01

    Small-scale mining in developing countries is generally labour-intensive and carried out with low levels of mechanization. In the Mererani area in the northern part of Tanzania, there are about 15000 underground miners who are constantly subjected to a poor working environment. Gemstones are found at depths down to 500 m. The objectives of this pilot study were to monitor the exposure to dust during work processes, which are typical of small-scale mining in developing countries, and to make a rough estimation of whether there is a risk of chronic pulmonary diseases for the workers. Personal sampling of respirable dust (n = 15) and 'total' dust (n = 5) was carried out during three consecutive days in one mine, which had a total of 50 workers in two shifts. Sampling started immediately before the miners entered the shaft, and lasted until they reappeared at the mine entrance after 5-8 h. The median crystalline silica content and the combustible content of the respirable dust samples were 14.2 and 5.5%, respectively. When drilling, blasting and shovelling were carried out, the exposure measurements showed high median levels of respirable dust (15.5 mg/m(3)), respirable crystalline silica (2.4 mg/m(3)), respirable combustible dust (1.5 mg/m(3)) and 'total' dust (28.4 mg/m(3)). When only shovelling and loading of sacks took place, the median exposures to respirable dust and respirable crystalline silica were 4.3 and 1.1 mg/m(3). This study shows that the exposure to respirable crystalline silica was high during underground small-scale mining. In the absence of personal protective equipment, the miners in the Mererani area are presumably at a high risk of developing chronic silicosis. PMID:12639837

  10. Downhill turn techniques and associated physical characteristics in cross-country skiers.

    PubMed

    Sandbakk, S Bucher; Supej, M; Sandbakk, Ø; Holmberg, H-C

    2014-08-01

    Three dominant techniques are used for downhill turning in cross-country skiing. In this study, kinematic, kinetic, and temporal characteristics of these techniques are described and related to skier strength and power. Twelve elite female cross-country skiers performed six consecutive turns of standardized geometry while being monitored by a Global Navigation Satellite System. Overall time was used as an indicator of performance. Skiing and turning parameters were determined from skier trajectories; the proportional use of each technique was determined from video analysis. Leg strength and power were determined by isometric squats and countermovement jumps on a force plate. Snow plowing, parallel skidding, and step turning were utilized for all turns. Faster skiers employed less snow plowing and more step turning, more rapid deceleration and earlier initiation of step turning at higher speed (r = 0.80-0.93; all P < 0.01). Better performance was significantly correlated to higher mean speed and shorter trajectory (r = 0.99/0.65; both P < 0.05) and to countermovement jump characteristics of peak force, time to peak force, and rate of force development (r = -0.71/0.78/-0.83; all P < 0.05). In conclusion, faster skiers used step turning to a greater extent and exhibited higher maximal leg power, which enabled them to combine high speeds with shorter trajectories during turns. PMID:23517089

  11. Soil erosion in river basins of Georgia

    NASA Astrophysics Data System (ADS)

    Gogichaishvili, G. P.

    2016-06-01

    The area of cultivated lands in western and eastern Georgia comprises 28-40 and 29-33% of the total catchment areas, respectively. Eroded arable soils in Georgia occupy 205700 ha, i.e. 30.5% of the total plowland area, including 110500 ha (16.4%) of slightly eroded soils, 74400 ha (11%) of moderately eroded soils, and 20800 ha (3.1%) of strongly eroded soils. The maximum denudation rate in catchments of western Georgia reaches 1.0 mm/yr. The minimum denudation (0.01 mm/yr.) is typical of river catchments in southern Georgia. The mean annual soil loss from plowed fields in western Georgia reaches 17.4 t/ha and exceeds the soil loss tolerance by nearly four times. In eastern Georgia, it is equal to 10.46 t/ha and exceeds the soil loss tolerance by 2.5 times. In southern Georgia, the mean annual soil loss from plowed fields is as low as 3.08 t per ha, i.e., much lower than the soil loss tolerance.

  12. Scaling and dynamics of washboard roads.

    PubMed

    Bitbol, Anne-Florence; Taberlet, Nicolas; Morris, Stephen W; McElwaine, Jim N

    2009-06-01

    Granular surfaces subjected to forces due to rolling wheels develop ripples above a critical speed. The resulting pattern, known as washboard or corrugated road, is common on dry unpaved roads. We investigated this phenomenon theoretically and experimentally using laboratory-scale apparatus and beds of dry sand. A thick layer of sand on a circular track was forced by a rolling wheel on an arm whose weight and moment of inertia could be varied. We compared the ripples made by the rolling wheel to those made using a simple inclined plow blade. We investigated the dependence of the critical speed on various parameters and described a scaling argument that leads to a dimensionless ratio, analogous to the hydrodynamic Froude number, which controls the instability. This represents the crossover between conservative dynamic forces and dissipative static forces. Above onset wheel-driven ripples move in the direction of motion of the wheel, but plow-driven ripples move in the reverse direction for a narrow range of Froude numbers. PMID:19658502

  13. Geographic applications of ERTS-1 imagery to landscape change. [Mississippi River and Great Smoky Mountains of Tennessee and North Carolina

    NASA Technical Reports Server (NTRS)

    Rehder, J. B. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. ERTS-1 has proven to be an effective earth-orbiting monitor of landscape change. Its regional coverage for large areal monitoring has been effective for the detection and mapping of agricultural plowing regions, for general forest cover mapping, for flood mapping, for strip mine mapping, and for short-lived precipitation mapping patterns. Paramount to the entire study has been the temporal coverage provided by ERTS. Without the cyclic coverage on an 18 day basis, temporal coverage would have been inadequate for the detection and mapping of strip mining landscape change, the analysis of agricultural landscape change based on plowing patterns, the analysis of urban-suburban growth changes, and the mapping of the Mississippi River floods. Cost benefits from ERTS are unquestionably superior to aircraft systems in regard to large regional coverage and cyclic temporal parameters. For the analysis of landscape change in large regions such as statewide areas or even areas of 10,000 square miles, ERTS is of cost benefit consideration. Not only does the cost of imagery favor ERTS but the reduction of man-hours using ERTS has been in the magnitude of 1:10.

  14. Evaluation of the possibility to use the plant-microbe interaction to stimulate radioactive 137Cs accumulation by plants in a contaminated farm field in Fukushima, Japan.

    PubMed

    Djedidi, Salem; Terasaki, Akimi; Aung, Han Phyo; Kojima, Katsuhiro; Yamaya, Hiroko; Ohkama-Ohtsu, Naoko; Bellingrath-Kimura, Sonoko Dorothea; Meunchang, Phatchayaphon; Yokoyama, Tadashi

    2015-01-01

    Field experiments in a contaminated farmland in Nihonmatsu city, Fukushima were conducted to assess the effectiveness of the plant-microbe interaction on removal of radiocesium. Before plowing, 93.3% of radiocesium was found in the top 5 cm layer (5,718 Bq kg DW(-1)). After plowing, Cs radioactivity in the 0-15 cm layer ranged from 2,037 to 3,277 Bq kg DW(-1). Based on sequential extraction, the percentage of available radiocesium (water soluble + exchangeable) was fewer than 10% of the total radioactive Cs. The transfer of (137)Cs was investigated in three agricultural crops; komatsuna (four cultivars), Indian mustard and buckwheat, inoculated with a Bacillus or an Azospirillum strains. Except for komatsuna Nikko and Indian mustard, inoculation with both strains resulted in an increase of biomass production by the tested plants. The highest (137)Cs radioactivity concentration in above-ground parts was found in Bacillus-inoculated komatsuna Nikko (121 Bq kg DW(-1)), accompanied with the highest (137)Cs TF (0.092). Furthermore, komatsuna Nikko-Bacillus and Indian mustard-Azospirillum associations gave the highest (137)Cs removal, 131.5 and 113.8 Bq m(-2), respectively. Despite the beneficial effect of inoculation, concentrations of (137)Cs and its transfer to the tested plants were not very high; consequently, removal of (137)Cs from soil would be very slow. PMID:25398196

  15. The effect of surface morphology on the friction of electrogalvanized sheet steel in forming processes

    SciTech Connect

    Skarpelos, P. N.

    1993-12-01

    The effect in the drawbead simulator test were evaluated for a set of commercially coated steels and a set of laboratory coated steels with underlying surfaces produced by laser textured, shot blast, and electro-discharge textured rolls. In general, surfaces with higher roughness (R{sub a} parameter) measured lower friction in the DBS tests. The requisite roughness amplitude necessary for low friction was moderated somewhat by having a more closely spaced roughness as described by the median wavelength, {lambda}m, of the power spectrum. This effect is due to interaction with the lubricant by the micro-roughness imparted by the galvanizing process. The lubricant tends to be retained better by the surfaces with the micro-roughness, thereby increasing the amount of elasto- and plasto-hydrodynamic support of the load. Other variables, such as large variations in thickness of the sheet can mask the effect of the surface by changing the actual distance of sliding contact during the DBS test. For tests where the amount of sliding is similar, the effect of roughness is significant. The friction measured for EG steels in the DBS test is dominated by deformation of the surface with plowing by the asperities of the tooling adding to that caused by the deformation. The size of the plow marks in the deformed surfaces corresponds to the roughness of the tooling and no significant evidence of wear particles was observed.

  16. Experimental evidence that human impacts drive fire ant invasions and ecological change

    PubMed Central

    King, Joshua R.; Tschinkel, Walter R.

    2008-01-01

    Biological invasions are often closely associated with human impacts and it is difficult to determine whether either or both are responsible for the negative impacts on native communities. Here, we show that human activity, not biological invasion, is the primary driver of negative effects on native communities and of the process of invasion itself. In a large-scale experiment, we combined additions of the exotic fire ant, Solenopsis invicta, with 2 disturbance treatments, mowing and plowing, in a fully crossed factorial design. Results indicate that plowing, in the absence of fire ants, greatly diminished total native ant abundance and diversity, whereas fire ants, even in the absence of disturbance, diminished some, but not all, native ant abundance and diversity. Transplanted fire ant colonies were favored by disturbance. In the absence of disturbance and on their own, fire ants do not invade the forest habitats of native ants. Our results demonstrate that fire ants are “passengers” rather than “drivers” of ecological change. We propose that fire ants may be representative of other invasive species that would be better described as disturbance specialists. Current pest management and conservation strategies should be reassessed to better account for the central role of human impacts in the process of biological invasion. PMID:19064909

  17. The pool of pedogenic carbon in the soils of different types and durations of use as croplands in the forest-steppe of the Central Russian Upland

    NASA Astrophysics Data System (ADS)

    Khokhlova, O. S.; Chendev, Yu. G.; Myakshina, T. N.; Shishkov, V. A.

    2013-05-01

    Based on studying five agrochronoseries, including recent forest (dark) gray soils and soils plowed for 100, 150, and 200-240 and more years in the forest-steppe zone of the Central Russian Upland, the dynamics of the pedogenic carbon pool, including the Corg and Ccarb, are considered. In the 2-m-thick layer of the agrogenic soils studied, the pedogenic carbon pool was shown to increase by 15-30% (up to 50%) mainly due to the changes in the Ccarb content. The insignificant (by ˜10%) growth of the Corg content was found in the soils that were plowed for more than 200-250 years. As the hydrothermal regime changed when passing from the forest to croplands, the Ccarb reserves increased due to the ascending of carbonates from the parent rock through the capillary pores, probably, in colloid solution-suspensions. This process proceeded without exchange with the soil CO2, since the 14C age and the content of the newly formed carbonates became higher. These carbonates may be called pedogenic-lithogenic agrocarbonates, since they appear in soils as a result of the (agro-) pedogenesis. In this case, their additional source is the lithogenic carbonates, which bring in the "old" carbon. The process of carbonates ascending could be referred to the rapid soil-forming ones with their implementation time being close to ≤50 years.

  18. Energy-related inventions program invention 637. Final technical report

    SciTech Connect

    1997-07-31

    The final technical report for the Pegasus plow, a stalk and root embedding apparatus, describes progress from the development stage to the product support stage. The US Department of Agriculture - Agriculture Research Service (ARS) is now in the second year of a three year study comparing the Pegasus to conventional tillage. So far, no downside has been with the Pegasus and the following benefits have been documented: (1) Energy savings of 65.0 kilowatt hours per hectare over conventional tillage. This is when the Pegasus plow is used to bury whole stalks, and represents a 70% savings over conventional tillage (92.5 kilowatt hours per hectare). (2) Four to seven fewer passes of tillage, depending on the particular situation. This represents a substantial time savings to farmers. (3) So far, no differences in cotton yields. Recent cotton boll counts in one study indicate a higher yield potential with the Pegasus. (4) No disease problems. (5) Significantly higher levels of organic matter in the soil. A hypothesis of the study is that whole stalk burial may reduce plant disease problems. This hypothesis has not yet been proven. (6) Significantly higher levels of nitrate nitrogen. Total nitrogen and ammonia nitrogen trended higher but were not significantly different. This shows that whole stalk burial does not adversely affect the nitrogen cycle in the soil and may actually improve it. The marketing support stage of the project is also described in the report.

  19. Modeling of 137Cs migration in soils using an 80-year soil archive: role of fertilizers and agricultural amendments.

    PubMed

    Monna, F; van Oort, F; Hubert, P; Dominik, J; Bolte, J; Loizeau, J-L; Labanowski, J; Lamri, J; Petit, C; Le Roux, G; Chateau, C

    2009-01-01

    An 80-year soil archive, the 42-plot experimental design at the INRA in Versailles (France), is used here to study long-term contamination by 137Cs atmospheric deposition and the fate of this radioisotope when associated with various agricultural practices: fallow land, KCl, NH4(NO3), superphosphate fertilizers, horse manure and lime amendments. The pertinence of a simple box model, where radiocaesium is supposed to move downward by convectional mechanisms, is checked using samples from control plots which had been neither amended, nor cultivated since 1928. This simple model presents the advantage of depending on only two parameters: alpha, a proportional factor allowing the historical atmospheric 137Cs fluxes to be reconstructed locally, and k, an annual loss coefficient from the plow horizon. Another pseudo-unknown is however necessary to run the model: the shape of historical 137Cs deposition, but this function can be easily computed by merging several curves previously established by other surveys. A loss of approximately 1.5% per year from the plow horizon, combined with appropriate fluxes, provides good concordance between simulated and measured values. In the 0-25cm horizon, the residence half time is found to be approximately 18yr (including both migration and radioactive decay). Migration rate constants are also calculated for some plots receiving continuous long-term agricultural treatments. Comparison with the control plots reveals significant influence of amendments on 137Cs mobility in these soils developed from a unique genoform. PMID:19013695

  20. Evaluation of cover crop and reduced cultivation for reducing nitrate leaching in Ireland.

    PubMed

    Hooker, K V; Coxon, C E; Hackett, R; Kirwan, L E; O'Keeffe, E; Richards, K G

    2008-01-01

    Nitrate (NO(3)) loss from arable systems to surface and groundwater has attracted considerable attention in recent years in Ireland. Little information exists under Irish conditions, which are wet and temperate, on the effects of winter cover crops and different tillage techniques on NO(3) leaching. This study investigated the efficacy of such practices in reducing NO(3) leaching from a spring barley (Hordeum vulgare L.) system in the Barrow River valley, southeast Ireland. The study compared the effect of two tillage systems (plow-based tillage and noninversion tillage) and two over-winter alternatives (no vegetative cover and a mustard cover crop) on soil solution NO(3) concentrations at 90 cm depth over two winter drainage seasons (2003/04 and 2004/05). Soil samples were taken and analyzed for inorganic N. During both years of the study, the use of a mustard cover crop significantly reduced NO(3) losses for the plowed and reduced cultivation treatments. Mean soil solution NO(3) concentrations were between 38 and 70% lower when a cover crop was used, and total N load lost over the winter was between 18 and 83% lower. Results from this study highlight the importance of drainage volume and winter temperatures on NO(3) concentrations in soil solution and overall N load lost. It is suggested that cover crops will be of particular value in reducing NO(3) loss in temperate regions with mild winters, where winter N mineralization is important and high winter temperatures favor a long growing season. PMID:18178886

  1. Removal of coagulant aluminum from water treatment residuals by acid.

    PubMed

    Okuda, Tetsuji; Nishijima, Wataru; Sugimoto, Mayo; Saka, Naoyuki; Nakai, Satoshi; Tanabe, Kazuyasu; Ito, Junki; Takenaka, Kenji; Okada, Mitsumasa

    2014-09-01

    Sediment sludge during coagulation and sedimentation in drinking water treatment is called "water treatment residuals (WTR)". Polyaluminum chloride (PAC) is mainly used as a coagulant in Japan. The recycling of WTR has been desired; one method for its reuse is as plowed soil. However, WTR reuse in this way is inhibited by the aluminum from the added PAC, because of its high adsorption capacity for phosphate and other fertilizer components. The removal of such aluminum from WTR would therefore be advantageous for its reuse as plowed soil; this research clarified the effect of acid washing on aluminum removal from WTR and on plant growth in the treated soil. The percentage of aluminum removal from raw WTR by sulphuric acid solution was around 90% at pH 3, the percentage decreasing to 40% in the case of a sun-dried sample. The maximum phosphate adsorption capacity was decreased and the available phosphorus was increased by acid washing, with 90% of aluminum removal. The enhancement of Japanese mustard spinach growth and the increased in plant uptake of phosphates following acid washing were observed. PMID:24835954

  2. Waterbird communities in rice fields subjected to different post-harvest treatments

    USGS Publications Warehouse

    Day, J.H.; Colwell, M.A.

    1998-01-01

    In California's Sacramento Valley, the potential value of rice fields as habitat for waterbirds may vary with harvest method, post-harvest treatment of rice straw (chopped, burned, plowed), and extent of flooding. Recent changes in rice harvesting methods (i.e., use of stripper-headers) and a legislative mandate to decrease burning of rice straw after harvest may alter habitat availability and use. Thus, we investigated species richness and community composition of nonbreeding waterbirds during October-March 1993-94 and 1994-95 in rice fields of the northern Sacramento Valley. Most (85-91% of land area) rice was conventionally harvested (i.e., cutter bar), and the remainder was stripped. Rice straw was left untreated in more than half of fields (52% in 1994 and 54% in 1995), especially in stripped fields (56-70%). In fields where farmers treated straw, the most common management methods were plowing (15-21%), burning (19-24%), and chopping (3-5%). Fields became increasingly wet from October through March as seasonal precipitation accumulated and farmers flooded fields to facilitate straw decomposition and provide habitat for ducks. Species richness of waterbirds was greater (P 0.23). Species richness in stripped fields probably was low because foraging opportunities were limited by tall dense straw, decreased grain density, and infrequent flooding. We recommend that land managers wishing to provide habitat for a diverse waterbird community harvest rice using conventional methods and flood fields shallowly.

  3. Variation Of Soil Moisture Patterns In Response To Anthropogenic Land Disturbances In A Semiarid Regional Landscape

    NASA Astrophysics Data System (ADS)

    Camarena, C.; Ren, J.; Jones, K.; Hempel, A.

    2005-12-01

    This project focuses on examination of the effects of various land management practices on soil moisture for semiarid regional landscapes. The project is at the Wellhausen Ranch Research Station located near Laredo, TX. This ranch has undergone various land disturbances such as root plowing and cattle overgrazing that have caused damage to the vegetation and natural communities. Two research sites were chosen within the ranch, one disturbed by root plowing and one undisturbed, to represent various land use environment. Soil moisture analysis was performed, using the WatchDog Irrigation System, to identify the effects of temperature, vegetation, diurnal, and seasonal effect on the soil moisture patterns. In addition, three soil moisture probes were placed on the same location at three different depths, 3, 5, and 8 inches, below the surface, to evaluate the soil moisture profile in vertical direction. Statistical analysis such as ANOVA, Friedman's test, and the sign test was conducted and the results suggested that soil moisture is influenced by land disturbances significantly in a semiarid regional landscape.

  4. Bird use of agricultural fields under reduced and conventional tillage in the Texas Panhandle

    USGS Publications Warehouse

    Flickinger, Edward L.; Pendleton, G.W.

    1994-01-01

    We conducted bird surveys in reduced-tillage and conventional tillage fields in spring, summer, fall, and winter from 1987 to 1991 in the Texas Panhandle. Eastern meadowlarks, longspurs, and savannah sparrows were more common in reduced-tillage (sorghum and wheat stubble) fields than in conventionally tilled (plowed) fields in at least 1 season. Other species also had patterns suggestive of greater abundance in reduced-tillage fields. Hornedlarks, which prefer habitat with sparse vegetation, were more abundant in plowed fields in all seasons except summer. Bird diversity was greater in reduced-tillage fields than in conventionally tilled fields in summer. Cover density and height were greater in reduced tillage fields in all seasons except spring. Cover density and height rather than cover composition (e.g.,grain stubble or live plants) seemed to be the important factors affecting bird distribution. Patterns of bird abundance between sorghum and wheat stubble fields also were dependent on cover. Herbicide use was not greater in reduced-tillage fields than in conventionally tilled fields. Reduced-tillage agriculture for sorghum and wheat farming should be encouraged in the southern Great Plains as a means of improving the attractiveness of agricultural land to many bird species.

  5. Specific features of bacterial communities in floodplain agrocenoses

    NASA Astrophysics Data System (ADS)

    Dobrovol'Skaya, T. G.; Leont'evskaya, E. A.; Sneg, A. A.; Balabko, P. N.

    2010-04-01

    The analysis of the taxonomic structure of the bacterial complexes in the alluvial soils of the Oka River valley allowed revealing the distinct differences in the spectrum of the bacterial dominants in the virgin and cultivated soils. Arthrobacter and pigment coryneform bacteria are shown to predominate in the virgin soil; bacilli and pseudomonades are common in the soil under vegetables. On cabbage leaves and carrot roots (both healthy and rotten), the spectrum of dominants is composed of two genera of enterobacteria: Pantoea and Erwinia. As a result of the plowing in of vegetables into the soil, enterobacteria accumulate; among them, phytopathogenic species are present. Within a year after this plowing in and the new yield, the enterobacteria practically disappeared, but myxobacteria and cytophages developed. Since these bacteria belong to the cellulose-destroying prokaryotes, the increase in their contents in the soil testified to their participation in the decomposition of the buried vegetable residues. Weeds are known to concentrate various bacterial forms in the phylloplane; they enter from different ecological niches: soil, water, meadow, and agricultural plants. Representatives of phytopathogenic bacteria as minor components were found on weeds.

  6. In vitro investigation of skin damage due to microscale shearing.

    PubMed

    Jee, Taekwon; Komvopoulos, Kyriakos

    2014-11-01

    Despite several studies dealing with the mechanical and tribological properties of skin, the majority of these investigations have been performed at macroscopic levels. However, because of the multilayer structure of skin, it is necessary to perform studies at microscopic scales to reveal the effect of individual layer constituents on the overall skin response to mechanical stimuli. To bridge the gap in knowledge of the micromechanical behavior of skin, a custom-made mechanical tester, optical microscopy, and cross-sectional histology were used to examine the deformation and tribological behavior of porcine skin subjected to various normal and shear loadings. Representative friction and wear results of skin tested under unidirectional and reciprocating (cyclic) shearing (scratching) conditions are interpreted in terms of the scratching speed, normal load, and number of scratch cycles to illustrate the effects of stratum corneum, cellular epidermis, and dermis on the friction and wear characteristics of skin. Depending on the normal load and scratch time (cycles), different friction mechanisms (i.e., adhesion, plowing, and squeeze-film lubrication) and wear mechanisms (i.e., surface plasticity/plowing, bulk shearing, cohesive failure, tearing, and delamination) were found to control shear-induced skin damage. The results of this study provide insight into microscale friction and wear processes influencing the mechanical response of skin subjected to normal and shear surface tractions. PMID:24323557

  7. Nanoscale contact mechanics of biocompatible polyzwitterionic brushes.

    PubMed

    Zhang, Zhenyu; Morse, Andrew J; Armes, Steven P; Lewis, Andrew L; Geoghegan, Mark; Leggett, Graham J

    2013-08-27

    Friction force microscopy has been used to demonstrate that biocompatible, lubricious poly(2-(methacryloyloxy)ethylphosphorylcholine) (PMPC) brushes exhibit different frictional properties depending on the medium (methanol, ethanol, 2-propanol, and water; the latter also with different quantities of added salt). The chemical functionalization of the probe (amine-, carboxylic acid-, and methyl-terminated probes were used) is not as important as the medium in determining the contact mechanics. For solvents such as methanol, where the adhesion between AFM probe and PMPC brushes is negligible, a linear friction-load relationship is observed. In contrast, the friction-load plot is nonlinear in ethanol or water, media in which stronger adhesion is measured. For ethanol, the data indicate Johnson-Kendall-Roberts (JKR) mechanics, whereas the Derjaguin-Muller-Toporov (DMT) model provided a good fit for the data acquired in water. Contact mechanics on zwitterionic PMPC brushes immersed in aqueous solutions of varying ionic strength followed the same trend, with high adhesion energies being correlated with a nonlinear friction-load relationship. These results can be rationalized by treating the friction force as the sum of a load-dependent term, attributed to molecular plowing, and an area-dependent shear term. In a good solvent for PMPC such as methanol, the shear term is negligible and the sliding interaction is dominated by molecular plowing. However, the adhesion energy is significantly larger in water and ethanol and the shear term is no longer negligible. PMID:23855771

  8. Potential of temperate agricultural soils for carbon sequestration: A meta-analysis of land-use effects.

    PubMed

    Kämpf, Immo; Hölzel, Norbert; Störrle, Maria; Broll, Gabriele; Kiehl, Kathrin

    2016-10-01

    Restoring depleted soil organic carbon (SOC) stocks of arable land to remove carbon from the atmosphere and offset fossil fuel emissions is a promising strategy for the mitigation of climate change. In agroecosystems conservational tillage practices and the abandonment of formerly plowed fields (ex-arable land) are shown to have the highest potential to sequester SOC. Nevertheless reported sequestration rates vary and the effects of environmental site conditions remain poorly understood. Our results are based on a meta-analysis of 273 paired SOC estimates from 65 publications which included only mineral soils from the temperate zone. SOC stocks of ex-arable grasslands with an average of 14years since abandonment were 18% larger compared to the SOC of arable land. Likewise, SOC stocks of never-plowed grassland plots were 11% larger than the SOC stocks of abandoned fields. The average sequestration rate was 0.72t Cha(-1)yr(-1). Semi-arid and sub-humid climate as well as low initial SOC stocks positively affected proportional SOC gains suggesting that the recovery of carbon stocks is not limited by low primary production. Therefore, the northward shift of cultivation areas in the temperate zone will lead to the abandonment of soils with high SOC recovery potential. However, if native soils are opened up elsewhere to compensate for yield losses due to abandonment the surplus of SOC in ex-arable land can easily be overcompensated by cultivation losses. PMID:27232969

  9. [Litter decomposition and nutrient release in Acacia mangium plantations established on degraded soils of Colombia].

    PubMed

    Castellanos-Barliza, Jeiner; León Peláez, Juan Diego

    2011-03-01

    Several factors control the decomposition in terrestrial ecosystems such as humidity, temperature, quality of litter and microbial activity. We investigated the effects of rainfall and soil plowing prior to the establishment of Acacia mangium plantations, using the litterbag technique, during a six month period, in forests plantations in Bajo Cauca region, Colombia. The annual decomposition constants (k) of simple exponential model, oscillated between 1.24 and 1.80, meanwhile k1 y k2 decomposition constants of double exponential model were 0.88-1.81 and 0.58-7.01. At the end of the study, the mean residual dry matter (RDM) was 47% of the initial value for the three sites. We found a slow N, Ca and Mg release pattern from the A. mangium leaf litter, meanwhile, phosphorus (P) showed a dominant immobilization phase, suggesting its low availability in soils. Chemical leaf litter quality parameters (e.g. N and P concentrations, C/N, N/P ratios and phenols content) showed an important influence on decomposition rates. The results of this study indicated that rainfall plays an important role on the decomposition process, but not soil plowing. PMID:21516640

  10. Modified patch-based locally optimal Wiener method for interferometric SAR phase filtering

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Huang, Haifeng; Dong, Zhen; Wu, Manqing

    2016-04-01

    This paper presents a modified patch-based locally optimal Wiener (PLOW) method for interferometric synthetic aperture radar (InSAR) phase filtering. PLOW is a linear minimum mean squared error (LMMSE) estimator based on a Gaussian additive noise condition. It jointly estimates moments, including mean and covariance, using a non-local technique. By using similarities between image patches, this method can effectively filter noise while preserving details. When applied to InSAR phase filtering, three modifications are proposed based on spatial variant noise. First, pixels are adaptively clustered according to their coherence magnitudes. Second, rather than a global estimator, a locally adaptive estimator is used to estimate noise covariance. Third, using the coherence magnitudes as weights, the mean of each cluster is estimated, using a weighted mean to further reduce noise. The performance of the proposed method is experimentally verified using simulated and real data. The results of our study demonstrate that the proposed method is on par or better than the non-local interferometric SAR (NL-InSAR) method.

  11. Modeling the effect of soil structure on water flow and isoproturon dynamics in an agricultural field receiving repeated urban waste compost application.

    PubMed

    Filipović, Vilim; Coquet, Yves; Pot, Valérie; Houot, Sabine; Benoit, Pierre

    2014-11-15

    Transport processes in soils are strongly affected by heterogeneity of soil hydraulic properties. Tillage practices and compost amendments can modify soil structure and create heterogeneity at the local scale within agricultural fields. The long-term field experiment QualiAgro (INRA-Veolia partnership 1998-2013) explores the impact of heterogeneity in soil structure created by tillage practices and compost application on transport processes. A modeling study was performed to evaluate how the presence of heterogeneity due to soil tillage and compost application affects water flow and pesticide dynamics in soil during a long-term period. The study was done on a plot receiving a co-compost of green wastes and sewage sludge (SGW) applied once every 2 years since 1998. The plot was cultivated with a biannual rotation of winter wheat-maize (except 1 year of barley) and a four-furrow moldboard plow was used for tillage. In each plot, wick lysimeter outflow and TDR probe data were collected at different depths from 2004, while tensiometer measurements were also conducted during 2007/2008. Isoproturon concentration was measured in lysimeter outflow since 2004. Detailed profile description was used to locate different soil structures in the profile, which was then implemented in the HYDRUS-2D model. Four zones were identified in the plowed layer: compacted clods with no visible macropores (Δ), non-compacted soil with visible macroporosity (Γ), interfurrows created by moldboard plowing containing crop residues and applied compost (IF), and the plow pan (PP) created by plowing repeatedly to the same depth. Isoproturon retention and degradation parameters were estimated from laboratory batch sorption and incubation experiments, respectively, for each structure independently. Water retention parameters were estimated from pressure plate laboratory measurements and hydraulic conductivity parameters were obtained from field tension infiltrometer experiments. Soil hydraulic

  12. Assessment of vertical soil solid phase transport (pedoturbations) in different types of land use by magnetic tracer method (Belgorod region, Russia)

    NASA Astrophysics Data System (ADS)

    Zhidkin, Andrey

    2015-04-01

    New method of quantitative assessments of vertical soil solid phase transport (pedoturbations) is based on redistribution of spherical magnetic particles (SMP) in soil profiles. SMP - are fly ash components, which mainly produce during coal burning. The main sources of SMP on studied object were locomotives on the railroads, which used coal at the turn of the XIX century. SMP income into the soil only from the atmosphere, very stable for destructions, can be preserved in soils for centuries, and have the same size and weight as the soil matter. So SMP redistribution reflects soil solid phase transport. SMP used as tracers of soil erosion (Olson et.al., 2013), but for the first time applied for quantitative assessments of pedoturbations. In Belgorod region of Russia studied vertical distribution of SMP in soils in different types of land use: a) arable chernozem about 160-year plowing, b) arable chernozem 120-year plowing, c) dark-gray forest soil, which didn't plow at least last 150 years. All three sites are located nearby for the same physical-geography conditions. Distribution of SMP studied layer by layer (thickness of the layer 7 cm) from the top to 70 cm depth, in triplicate soil columns in every land use type (totally 90 soil samples). The period of SMP kept in studied soils is about 115 years. Revealed the different depth of SMP penetration (burial) in soil profiles for this period: 49 cm in the soil of 160-year arable land, 58 cm in the soil of 120-year arable land and 68 cm in the virgin forest soil. Different depth of SMP penetration is connected with different activity of pedoturbations, which differs according to the composition of soil flora and fauna, root activity, and animal mixing work. It is supposed that in the arable land single cropping can reduce the thickness of the active layer and as a result the zone of active pedoturbation depth. Based on SMP distribution counted rates of vertical soil solid phase transport, which are equaled: 31 t

  13. Patterns of rock fragment cover generated by tillage erosion

    NASA Astrophysics Data System (ADS)

    Poesen, Jean; Wesemael, Bas van; Govers, Gerard; Martinez-Fernandez, José; Desmet, Philippe; Vandaele, Karel; Quine, Timothy; Degraer, Greet

    1997-03-01

    Intensively cultivated areas in the upper part of the Guadalentin catchment (southeast Spain) show a systematic spatial pattern of surface rock fragment cover ( Rc). The objective of this paper is to quantify and to explain this spatial rock fragment cover pattern. Therefore, a map of an intensively cultivated area of 5 km 2 was digitised, and for each pixel total topographic curvature was calculated. Next, rock fragment cover was determined photographically at 35 sites with a range of total slope curvatures. A linear relation between total curvature and rock fragment cover was found, except for narrow concavities. It was hypothesised that this pattern can be explained by a significant net downslope movement of rock fragments and fine earth by tillage. The displacement distances of rock fragments by tillage with a duckfoot chisel were measured by monitoring the displacement of tracers (painted rock fragments and aluminium cubes) on 5 sites having different slopes. The rare of tillage erosion for one tillage pass with a duckfoot chisel, expressed by the diffusion constant ( k), equals 282 kg/m for up and downslope tillage and only 139 kg/m for contour tillage. Nomograms indicate that mean denudation rates in almond groves due to tillage erosion (3 to 5 tillage passes per year) can easily amount to 1.5-2.6 mm/year for contour tillage and up to 3.6-5.9 mm/year for up- and downslope tillage for a field, 50 m long and having a slope of 20%. These figures are at least one order of magnitude larger than reported denudation rates caused by water erosion in similar environments. Hence tillage erosion contributes significantly to land degradation. The downslope soil flux induced by tillage not only causes considerable denudation on topographic convexities (hill tops and spurs) and upper field boundaries but also an important sediment accumulation in topographic concavities (hollows and valley bottoms) and at lower field boundaries. Kinetic sieving (i.e. the upward migration

  14. Water erosion during a 17-year period under two crop rotations in four soil management systems on a Southbrazilian Inceptisol

    NASA Astrophysics Data System (ADS)

    Bertol, Ildegardis; Vidal Vázquez, Eva; Paz Ferreiro, Jorge

    2010-05-01

    Soil erosion still remains a persistent issue in the world, and this in spite of the efforts to ameliorate soil management systems taken into account the point of view of environmental protection against soil losses. In South Brazil water erosion is mainly associated to rainfall events with a great volume and high intensity, which are more or less evenly distributed all over the year. Nowadays, direct drilling is the most widely soil management system used for the main crops of the region. However, some crops still are grown on conventionally tilled soils, which means mainly ploughing and harrowing and less frequently chisel ploughing. In Lages-Santa Catarina State, Brazil, a plot experiment under natural rain was started in 1992 on an Inceptisol with the aim of quantifying soil and water losses. Treatments included bare and vegetated plots. The crop succession was: oats (Avena strigosa), soybean (Glycine max), vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and beans (Phaseolus vulgaris). Soil tillage systems investigated in this study were: i) conventional tillage (CT), ii) reduced tillage (MT), iii) no tillage (NT) under crop rotation and iv) conventional tillage on bare soil (BS). Treatments CT and BS involved ploughing plus twice harrowing, whereas MT involved chisel ploughing plus harrowing. Rainfall erosivity from January 1 1992 to December 31 2009 was calculated. Soil losses from the BS treatment along the 17 year study period were higher than 1200 Mg ha-1. Crop cover significantly reduced erosion, so that under some crops soil losses in the CT treatment were 80% lower than in the BS treatment. In turn soil losses in the MT treatment, where tillage was performed by chiselling and harrowing, were on average about 50% lower than in the CT treatment. No tillage was the most efficient soil management system in reducing soil erosion, so that soil losses in the NT treatment were about 98% lower than in the BS treatment. The three

  15. Fault Wear and Friction Evolution: Experimental Analysis

    NASA Astrophysics Data System (ADS)

    Boneh, Y.; Chang, J. C.; Lockner, D. A.; Reches, Z.

    2011-12-01

    Wear is an inevitable product of frictional sliding of brittle rocks as evidenced by the ubiquitous occurrence of fault gouge and slickenside striations. We present here experimental observations designed to demonstrate the relationship between wear and friction and their governing mechanisms. The experiments were conducted with a rotary shear apparatus on solid, ring-shaped rock samples that slipped for displacements up to tens of meters. Stresses, wear and temperature were continuously monitored. We analyzed 86 experiments of Kasota dolomite, Sierra White granite, Pennsylvania quartzite, Karoo gabbro, and Tennessee sandstone at slip velocities ranging from 0.002 to 0.97 m/s, and normal stress from 0.25 to 6.9 MPa. We conducted two types of runs: short slip experiments (slip distance < 25 mm) primarily on fresh, surface-ground samples, designed to analyze initial wear mechanisms; and long slip experiments (slip distance > 3 m) designed to achieve mature wear conditions and to observe the evolution of wear and friction as the fault surfaces evolved. The experiments reveal three wear stages: initial, running-in, and steady-state. The initial stage is characterized by (1) discrete damage striations, the length of which is comparable to total slip , and local pits or plow features; (2) timing and magnitude of fault-normal dilation corresponds to transient changes of normal and shear stresses; and (3) surface roughness increasing with the applied normal stress. We interpret these observations as wear mechanisms of (a) plowing into the fresh rock surfaces; (b) asperity breakage; and (c) asperity climb. The running-in stage is characterized by (1) intense wear-rate over a critical wear distance of Rd = 0.3-2 m; (2) drop of friction coefficient over a weakening distance of Dc = 0.2-4 m; (3) Rd and Dc display positive, quasi-linear relation with each other. We interpret these observations as indicating the organizing of newly-created wear particles into a 'three

  16. Tabletop Tectonics: Diverse Mountain Ranges Using Flour and Graphite

    NASA Astrophysics Data System (ADS)

    Davis, D. M.

    2006-12-01

    It has been recognized for some time that the frontal deformation zones where plates converge (foreland fold- and-thrust belts on continents and accretionary wedges at subduction zones) involve shortening over a decoupling layer, or decollement. A simple but successful way of explaining many aspects of their behavior is called the critical Coulomb wedge model, which regards these contractional wedges as analogous to the wedge-shaped mass of soil accreted in front of a bulldozer, or the wedge of snow that piles up in front of a snow plow. The shape and deformation history of the accreted wedge of soil or snow will depend upon the frictional strength of the material being plowed up and the surface over which it is being plowed. The same is true of `bulldozer' wedges consisting of many km thick piles of sediment at convergent plate margins. Using flour (or powdered milk), sandpaper, graphite, transparency sheets, and athletic field marker chalk, manipulated with sieves, brushes, pastry bags and blocks and sheets of wood, it is possible to demonstrate a wide variety of processes and tectonic styles observed at convergent plate boundaries. Model fold-and-thrust belts that behave like natural examples with a decollement that is strong (e.g., in rock without high pore fluid pressure) or weak (e.g., in a salt horizon or with elevated pore fluid pressure) can be generated simply by placing wither sandpaper or graphite beneath the flour that is pushed across the tabletop using a block of wood (the strong basement and hiterland rocks behind the fold-thrust belt). Depending upon the strength of the decollement, the cross-sectional taper of the deforming wedge will be thin or broad, the internal deformation mild or intense, and the structures either close to symmetric or strongly forward-vergent, just as at the analogous natural fold-thrust belts. Including a horizontal sheet of wood or Plexiglas in front of the pushing block allows generation of an accretionary wedge, outer

  17. Lateral Distribution of Polycyclic Aromatic Hydrocarbons and Spherical Magnetic Particles within Soil Catenas of the Arable Watershed (Tver Region, Russia)

    NASA Astrophysics Data System (ADS)

    Koshovskii, Timur; Zhidkin, Andrei; Gennadiev, Alexander

    2015-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are very dangerous substances because of their carcinogenic properties. It is important to know the features of PAHs transport and accumulation in soils, especially on agricultural lands. Unfortunately this scientific problem is studied not enough. It is known that predominantly PAHs in soils are sorbed on solid phase particles [2], so redistribution of PAHs should be carried out with transport of soil solid phase matter. For the purpose of assessment of connections between PAHs and soil solid phase transport the lateral distribution of PAHs and spherical magnetic particles (SMP) as tracers of soil solid phase migration has been compared. SMP is the component of fly ash which is used last two decades for quantitative assessment of soil erosion [1]. Studies were conducted in small watershed of south-taiga zone in European part of Russia in Tver region. The watershed has 53 ha, steep slopes, less 50, convex and convexo-concave shapes with ridges and runnels. The watershed lands were plowed up for the last 350-400 years until 1995 year. Predominant soils are Umbric Albeluvisols. Soil samples were selected at four soil catenas (30 points with average distance about 70 meters). Two catenas were on opposite slopes near the road, and other two catenas were located on the opposite slopes (250-400 m from the road). It is revealed that average concentration of PAHs in studied soils are 105 ng/g, and varies from 11 to 770 ng/g, with coefficient of variation 143%. Lateral distribution of PAHs and SMP differs within different catenas, because of various factors influence on PAHs concentrations: 1) amounts of PAHs income, depending on the distance from the source; 2) homogenization of PAHs concentrations within arable layer because of mixing the soil matter due to plowing; 3) vertical transport of PAHs in subarable layers is also connected with plowing and bioturbation; 4) rates of decomposition of PAHs in arable layer, depending on

  18. Bacteria-to-Archaea ratio depending on soil depth and agrogenic impact

    NASA Astrophysics Data System (ADS)

    Semenov, Mikhail; Manucharova, Natalia; Kuzyakov, Yakov

    2014-05-01

    Archaeal communities and their potential roles in the soil ecosystem are affected by a number of soil proprerties and environmental factors. Competitive interactions between Archaea and Bacteria play a particular role in spread and abundance of these two domains. Therefore, the goal of the study was to evaluate the Bacteria-to-Archaea ratio in different soils. The research was carried out at field and natural ecosystems of European part of Russia. Samples were collected within the soil profiles (3-6 horizons) of chernozem and kastanozem with distinctly different agrogenic impact. In situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes (FISH) was used to determine the abundance of metabolically active cells of Archaea and Bacteria. The Cmic, Corg, C/N, DNA content and growth characteristics have been analyzed as well. Determination of number of metabolically active cells in chernozem under arable land and forest revealed that abundance of Archaea in topsoil under forest was higher more than 2 times comparing with arable land, but leveled off in the deeper horizons. Plowing of Chernozem decreased amount of archaeal and bacterial active cells simultaneously, however, Bacteria were more resistant to agrogenic impact than Archaea. Determination of the taxonomic composition within Bacteria domain showed a significant decrease in the abundance of phylogenetic groups Firmicutes and Actinobacteria in the topsoil under arable land comparing to the forest, which is the main reason for the declining of the total amount of prokaryotic cells. In kastanozem significant change in the number of metabolically active cells due to plowing was detected only within 40 cm soil layer, and this effect disappeared in lower horizons. The number of Archaea was higher in the upper horizons of arable as compared to virgin soil. Conversely, the number of Bacteria in the upper layers of the soil after plowing kastanozem decreased. Relationship between soil organic

  19. Individual quality, survival variation and patterns of phenotypic selection on body condition and timing of nesting in birds

    USGS Publications Warehouse

    Blums, P.; Nichols, J.D.; Hines, J.E.; Lindberg, M.; Mednis, A.

    2005-01-01

    Questions about individual variation in 'quality' and fitness are of great interest to evolutionary and population ecologists. Such variation can be investigated using either a random effects approach or an approach that relies on identifying observable traits that are themselves correlated with fitness components. We used the latter approach with data from 1,925 individual females of three species of ducks (tufted duck, Aythya fuligula; common pochard, Aythya ferina; northern shoveler, Anas clypeata) sampled on their breeding grounds at Engure Marsh, Latvia, for over 15 years. Based on associations with reproductive output, we selected two traits, one morphological (relative body condition) and one behavioral (relative time of nesting), that can be used to characterize individual females over their lifetimes. We then asked whether these traits were related to annual survival probabilities of nesting females. We hypothesized quadratic, rather than monotonic, relationships based loosely on ideas about the likely action of stabilizing selection on these two traits. Parameters of these relationships were estimated directly using ultrastructural models embedded within capture-recapture-band-recovery models. Results provided evidence that both traits were related to survival in the hypothesized manner. For all three species, females that tended to nest earlier than the norm exhibited the highest survival rates, but very early nesters experienced reduced survival and late nesters showed even lower survival. For shovelers, females in average body condition showed the highest survival, with lower survival rates exhibited by both heavy and light birds. For common pochard and tufted duck, the highest survival rates were associated with birds of slightly above-average condition, with somewhat lower survival for very heavy birds and much lower survival for birds in relatively poor condition. Based on results from this study and previous work on reproduction, we conclude that

  20. A rapid, controlled-environment seedling root screen for wheat correlates well with rooting depths at vegetative, but not reproductive, stages at two field sites

    PubMed Central

    Watt, M.; Moosavi, S.; Cunningham, S. C.; Kirkegaard, J. A.; Rebetzke, G. J.; Richards, R. A.

    2013-01-01

    Background and Aims Root length and depth determine capture of water and nutrients by plants, and are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to determine speed, repeatability and relatedness to performance of young and adult plants in the field. Methods Recombinant inbred lines (RILs) and diverse genotypes were grown in rolled, moist germination paper in growth cabinets, and primary root number and length were measured when leaf 1 or 2 were fully expanded. For comparison, plants were grown in the field and root systems were harvested at the two-leaf stage with either a shovel or a soil core. From about the four-leaf stage, roots were extracted with a steel coring tube only, placed directly over the plant and pushed to the required depth with a hydraulic ram attached to a tractor. Key Results In growth cabinets, repeatability was greatest (r = 0·8, P < 0·01) when the paper was maintained moist and seed weight, pathogens and germination times were controlled. Scanned total root length (slow) was strongly correlated (r = 0·7, P < 0·01) with length of the two longest seminal axile roots measured with a ruler (fast), such that 100–200 genotypes were measured per day. Correlation to field-grown roots at two sites at two leaves was positive and significant within the RILs and cultivars (r = 0·6, P = 0·01), and at one of the two sites at the five-leaf stage within the RILs (r = 0·8, P = 0·05). Measurements made in the field with a shovel or extracted soil cores were fast (5 min per core) and had significant positive correlations to scanner measurements after root washing and cleaning (>2 h per core). Field measurements at two- and five-leaf stages did not correlate with root depth at flowering. Conclusions The seedling screen was fast, repeatable and reliable for selecting lines with greater total root length in the young vegetative phase in the field. Lack of significant correlation with reproductive stage

  1. Limitations of using a thermal imager for snow pit temperatures

    NASA Astrophysics Data System (ADS)

    Schirmer, M.; Jamieson, B.

    2013-10-01

    Driven by temperature gradients, kinetic snow metamorphism is important for avalanche formation. Even when gradients appear to be insufficient for kinetic metamorphism, based on temperatures measured 10 cm apart, faceting close to a~crust can still be observed. Recent studies that visualized small scale (< 10 cm) thermal structures in a profile of snow layers with an infrared (IR) camera produced interesting results. The studies found melt-freeze crusts to be warmer or cooler than the surrounding snow depending on the large scale gradient direction. However, an important assumption within the studies was that a thermal photo of a freshly exposed snow pit was similar enough to the internal temperature of the snow. In this study, we tested this assumption by recording thermal videos during the exposure of the snow pit wall. In the first minute, the results showed increasing gradients with time, both at melt-freeze crusts and at artificial surface structures such as shovel scours. Cutting through a crust with a cutting blade or a shovel produced small concavities (holes) even when the objective was to cut a planar surface. Our findings suggest there is a surface structure dependency of the thermal image, which is only observed at times with large temperature differences between air and snow. We were able to reproduce the hot-crust/cold-crust phenomenon and relate it entirely to surface structure in a temperature-controlled cold laboratory. Concave areas cooled or warmed slower compared with convex areas (bumps) when applying temperature differences between snow and air. This can be explained by increased radiative transfer or convection by air at convex areas. Thermal videos suggest that such processes influence the snow temperature within seconds. Our findings show the limitations of the use of a thermal camera for measuring pit-wall temperatures, particularly in scenarios where large gradients exist between air and snow and the interaction of snow pit and

  2. Limitations of using a thermal imager for snow pit temperatures

    NASA Astrophysics Data System (ADS)

    Schirmer, M.; Jamieson, B.

    2014-03-01

    Driven by temperature gradients, kinetic snow metamorphism plays an import role in avalanche formation. When gradients based on temperatures measured 10 cm apart appear to be insufficient for kinetic metamorphism, faceting close to a crust can be observed. Recent studies that visualised small-scale (< 10 cm) thermal structures in a profile of snow layers with an infrared (IR) camera produced interesting results. The studies found melt-freeze crusts to be warmer or cooler than the surrounding snow depending on the large-scale gradient direction. However, an important assumption within these studies was that a thermal photo of a freshly exposed snow pit was similar enough to the internal temperature of the snow. In this study, we tested this assumption by recording thermal videos during the exposure of the snow pit wall. In the first minute, the results showed increasing gradients with time, both at melt-freeze crusts and artificial surface structures such as shovel scours. Cutting through a crust with a cutting blade or shovel produced small concavities (holes) even when the objective was to cut a planar surface. Our findings suggest there is a surface structure dependency of the thermal image, which was only observed at times during a strong cooling/warming of the exposed pit wall. We were able to reproduce the hot-crust/cold-crust phenomenon and relate it entirely to surface structure in a temperature-controlled cold laboratory. Concave areas cooled or warmed more slowly compared with convex areas (bumps) when applying temperature differences between snow and air. This can be explained by increased radiative and/or turbulent energy transfer at convex areas. Thermal videos suggest that such processes influence the snow temperature within seconds. Our findings show the limitations of using a thermal camera for measuring pit-wall temperatures, particularly during windy conditions, clear skies and large temperature differences between air and snow. At crusts or other

  3. Carbon supply and storage in tilled and nontilled soils as influenced by cover crops and nitrogen fertilization.

    PubMed

    Sainju, Upendra M; Singh, Bharat P; Whitehead, Wayne F; Wang, Shirley

    2006-01-01

    Soil carbon (C) sequestration in tilled and nontilled areas can be influenced by crop management practices due to differences in plant C inputs and their rate of mineralization. We examined the influence of four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)], biculture of legume and nonlegume (vetch and rye), and no cover crops (or winter weeds)} and three nitrogen (N) fertilization rates (0, 60 to 65, and 120 to 130 kg N ha(-1)) on C inputs from cover crops, cotton (Gossypium hirsutum L.), and sorghum [Sorghum bicolor (L.) Moench)], and soil organic carbon (SOC) at the 0- to 120-cm depth in tilled and nontilled areas. A field experiment was conducted on Dothan sandy loam (fine-loamy, siliceous, thermic Plinthic Paleudults) from 1999 to 2002 in central Georgia. Total C inputs to the soil from cover crops, cotton, and sorghum from 2000 to 2002 ranged from 6.8 to 22.8 Mg ha(-1). The SOC at 0 to 10 cm fluctuated with C input from October 1999 to November 2002 and was greater from cover crops than from weeds in no-tilled plots. In contrast, SOC values at 10 to 30 cm in no-tilled and at 0 to 60 cm in chisel-tilled plots were greater for biculture than for weeds. As a result, C at 0 to 30 cm was sequestered at rates of 267, 33, -133, and -967 kg C ha(-1) yr(-1) for biculture, rye, vetch, and weeds, respectively, in the no-tilled plot. In strip-tilled and chisel-tilled plots, SOC at 0 to 30 cm decreased at rates of 233 to 1233 kg C ha(-1) yr(-1). The SOC at 0 to 30 cm increased more in cover crops with 120 to 130 kg N ha(-1) yr(-1) than in weeds with 0 kg N ha(-1) yr(-1), regardless of tillage. In the subtropical humid region of the southeastern United States, cover crops and N fertilization can increase the amount of C input and storage in tilled and nontilled soils, and hairy vetch and rye biculture was more effective in sequestering C than monocultures or no cover crop. PMID:16825471

  4. Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

    2009-01-01

    The term "rotary percussive auto-gopher" denotes a proposed addition to a family of apparatuses, based on ultrasonic/ sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive autogopher, the emphasis would be on developing an apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses. To recapitulate from the prior articles about USDCs: A USDC can be characterized as a lightweight, low-power jackhammer in which a piezoelectrically driven actuator generates ultrasonic vibrations and is coupled to a tool bit through a free mass. The bouncing of the free mass between the actuator horn and the drill bit converts the actuator ultrasonic vibrations into sonic hammering of the drill bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary rotary drilling, ordinary hammering, or ordinary steady pushing. The predecessor of the rotary percussive auto-gopher is an apparatus, now denoted an ultrasonic/sonic gopher and previously denoted an ultrasonic gopher, described in "Ultrasonic/ Sonic Mechanism for Drilling and Coring" (NPO-30291), NASA Tech Briefs Vol. 27, No. 9 (September 2003), page 65. The ultrasonic/sonic gopher is intended for use mainly in acquiring cores. The name of the apparatus reflects the fact that, like a

  5. Prevention of vertebral body–splitting fractures after multilevel ProDisc-L implantation

    PubMed Central

    Sullivan, Humbert G.; Bertagnoli, Rudolf; Nigogosyan, Mark A.; Ladwig, Nicholas R.; Born, Hayley L.; Cerniglia, Molly M.; Habbicht, Hartmann; Mathiason, Michelle A.; McHugh, Vicki L.

    2012-01-01

    Background Prior studies of multilevel ProDisc-L (PD-L) implants (Synthes Spine, Inc., West Chester, Pennsylvania) using the standard US technique have used conventional radiography postoperatively. We found vertebral body–splitting fractures (VB-SFs) in interposed vertebral bodies after 5 sequential multilevel PD-L device implantations using the standard US technique. These were identified with postoperative computed tomography (CT) but were not visible on plain radiographs. In an additional patient, we found that a stress-relieving, pilot holes–only technique did not prevent VB-SFs. The 5 patients operated on with the standard technique composed the background series against which we compared the incidence of VB-SFs in patients operated on with a modification of the standard US technique—a combination of stress-relieving pilot holes, removal of cortex in the chisel path, and a fenestrated chisel (PH/CR/FC)—intended to reduce the incidence of VB-SFs in multilevel PD-L constructs. Methods Patients receiving multilevel PD-L implants at 2 sites—1 in the United States and the other in Germany—were operated on with the PH/CR/FC technique and their postoperative CT scans evaluated for the presence of VB-SFs. The frequency of VB-SFs in these patients was compared with that of the 5 patients from the background series who were operated on by the standard US technique. The groups’ mean sex, age, body mass index, and vertebral body height, as well as average spinal T score, were also compared. Results No fractures were found in 13 interposed vertebral bodies in 11 patients operated on with the PH/CR/FC technique, as compared with 4 VB-SFs and 1 anterior keel cut–to–anterior keel cut fracture in 5 interposed vertebral bodies in 5 patients operated on with the US technique (P ≤ .001). Although the sample sizes were small, this difference in fracture rate was not associated with sex, age, body mass index, or average spinal T score. At up to 13 months of

  6. Effects of chipping, grinding, and heat on survival of emerald ash borer, Agrilus planipennis (Coleoptera: Buprestidae), in chips.

    PubMed

    McCullough, Deborah G; Poland, Therese M; Cappaert, David; Clark, Erin L; Fraser, Ivich; Mastro, Victor; Smith, Sarah; Pell, Christopher

    2007-08-01

    The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), a phloem-feeding insect from Asia, was identified in 2002 as the cause of widespread ash (Fraxinus sp.) mortality in southeastern Michigan and Essex County, Ontario. Most larvae overwinter as nonfeeding prepupae in the outer sapwood or thick bark of large trees. In a series of studies, we evaluated effects of grinding, chipping, and heat treatment on survival of A. planipennis prepupae in ash material. Heavily infested ash bolts containing roughly 8,700 prepupae were processed by a horizontal grinder with either a 2.5- or 10-cm screen. There was no evidence of A. planipennis survival in chips processed with the 2.5-cm screen, but eight viable prepupae were recovered from chips processed with the 10-cm screen. We chiseled additional sentinel chips with prepupae from ash logs and buried 45 in each chip pile. In total, six prepupae in sentinel chips survived the winter, but we found no sign of adult A. planipennis emergence from the processed chips. Subsequently, we assessed prepupal survival in chips processed by a chipper or a horizontal grinder fit with 5-, 10-, or 12.7-cm screens. An estimated 1,565 A. planipennis prepupae were processed by each treatment. Chips from the chipper were shorter than chips from the grinder regardless of the screen size used. No live prepupae were found in chips produced by the chipper, but 21 viable prepupae were found in chips from the grinder. Infested wood and bark chips chiseled from logs were held in ovens at 25, 40, or 60 degrees C for 8, 24, or 48 h. Prepupal survival was consistently higher in wood chips than bark chips at 40 degrees C, whereas no prepupae survived exposure to 60 degrees C for eight or more hours. In a second study, prepupae in wood chips were exposed to 40, 45, 50, 55, or 60 degrees C for 20 or 120 min. Some prepupae survived 20 min of exposure to all temperatures. No prepupae survived exposure to 60 degrees C for 120 min, but 17

  7. Control of Structure in Conventional Friction Stir Welds through a Kinematic Theory of Metal Flow

    NASA Technical Reports Server (NTRS)

    Rubisoff, H.A.; Schneider, J.A.; Nunes, A.C.

    2009-01-01

    In friction stir welding (FSW), a rotating pin is translated along a weld seam so as to stir the sides of the seam together. Metal is prevented from flowing up the pin, which would result in plowing/cutting instead of welding, by a shoulder on the pin. In conventional FSW, the weld metal rests on an "anvil", which supports the heavy "plunge" load on the tool. In this study, both embedded tungsten wires along and copper plating on the faying surfaces were used to trace the flow of AA2219 weld metal around the C-FSW tool. The effect of tool rotational speed, travel speed, plunge load, and pin thread pitch on the resulting weld metal flow was evaluated. Plan, longitudinal, and transverse section x-ray radiographs were examined to trace the metal flow paths. The results are interpreted in terms of a kinematic theory of metal flow in FSW.

  8. Fungal spores and pollen in particulate matter collected during agricultural activities in the Po Valley (Italy).

    PubMed

    Telloli, Chiara; Chicca, Milvia; Leis, Marilena; Vaccaro, Carmela

    2016-08-01

    Airborne particulate matter (PM) containing fungal spores and pollen grains was sampled within a monitoring campaign of wheat threshing, plowing and sowing agricultural operations. Fungal spores and pollen grains were detected and identified on morphological basis. No studies were previously available about fungal spore and pollen content in agricultural PM in the Po Valley. Sampling was conducted in a Po Valley farmland in Mezzano (Ferrara, Italy). The organic particles collected were examined by scanning electron microscopy with energy dispersive X-ray spectrometer. Fungal spores and pollen grains were identified when possible at the level of species. The most frequent components of the organic particles sampled were spores of Aspergillus sp., which could represent a risk of developing allergies and aspergillosis for crop farmers. PMID:27521955

  9. Brine release based on structural calculations of damage around an excavation at the Waste Isolation Pilot Plant (WIPP)

    SciTech Connect

    Munson, D.E.; Jensen, A.L.; Webb, S.W.; DeVries, K.L.

    1996-02-01

    In a large in situ experimntal circular room, brine inflow was measured over 5 years. After correcting for evaporation losses into mine ventilation air, the measurements gave data for a period of nearly 3 years. Predicted brine accumulation based on a mechanical ``snow plow`` model of the volume swept by creep-induced damage as calculated with the Multimechanism Deformation Coupled Fracture model was found to agree with experiment. Calculation suggests the damage zone at 5 years effectively exends only some 0.7 m into the salt around the room. Also, because the mecahnical model of brine release gives an adequate explanation of the measured data, the hydrological process of brine flow appears to be rapid compared to the mechanical process of brine release.

  10. Human response to buffeting in an all-terrain vehicle.

    PubMed

    Fraser, T M; Smiley, A M; Mottershead, B E

    1976-01-01

    Suitably prepared subjects were exposed to the vibration imposed by driving a personal-type all-terrain vehicle over a heavily plowed track. Acceleration was measured in the Z-axis at the seat of the vehicle, and in the X, Y, and Z axes at the hip and head of the subjects. Acceleration peaks, rates of onset, durations, and frequency ranges were determined and a spectral analysis conducted. Results showed that, for this vehicle under the test circumstances, the subjects respond with a low-frequency (less than 4 Hz) oscillation at approximately 0.5 Gz above nominal, on which are imposed numerous peaks of 1 to 5 G, or higher with rates of onset within the range measured, of 20 to 100 G/s. Although the measurement system did not conform to ISO (International Standards Organization) requirements, the results suggest that continued exposure would exceed the ISO 1-min limit for "health and safety." PMID:1247443

  11. Clues to galaxy activity from rich cluster simulations

    NASA Technical Reports Server (NTRS)

    Evrard, August E.

    1990-01-01

    New simulations of rich cluster evolution are used to evaluate the first infall hypothesis of Gunn and Dressler - the idea that the enhanced fraction of active galaxies seen in high redshift clusters is due to a one-time burst of star formation triggered by the rapid rise in external pressure as a galaxy plows into the hot intracluster medium (ICM). Using three-dimensional simulations which contain both baryonic gas and collisionless dark material, local static pressure histories for test orbits of galaxies are generated and a simple trigger threshold based on dP/dt/P sub ISM is applied to define an active fraction of the population. The results lend qualitative and quantitative support to the first infall interpretation.

  12. Evaluation of remote sensing in control of pink bollworm in cotton. [Southern California deserts

    NASA Technical Reports Server (NTRS)

    Lewis, L. N. (Principal Investigator); Coleman, V. B.

    1973-01-01

    The author has identified the following significant results. The main objective is to evaluate the use of a satellite in monitoring the cotton production regulation program of the State of California as an aid in controlling pink bollworm infestation in the southern deserts of California. Color combined images of ERTS-1 multispectral images simulating color infrared are being used for crop identification. The status of each field (i.e., crop, bare, harvested, wet, plowed) is mapped from the imagery and is then compared to ground survey information taken at the time of ERTS-1 overflights. A computer analysis has been performed to compare field and satellite data to a crop calendar. Correlation to data has been 97% for field condition. Actual crop identification varies; cotton identification is only 63% due to lack of full season coverage.

  13. Application of magnetic tracer method for quantification of pedoturbations in soils under different land use

    NASA Astrophysics Data System (ADS)

    Zhidkin, Andrey; Gennadiyev, Alexander

    2014-05-01

    with residually accumulative SMP distribution (15-75%). Revealed the important role of type of plowing. On two sites in Russia with depleted type of plowing detected very high intensity of pedoturbation - homogenous type of SMP distribution was in 8-17% of soils and accumulative type - in 15-25%. Otherwise on two sites in the Middle West USA with moldboard type of plowing, homogenous type was much less (in 0-8% of soils) and accumulative type was 2-3 times more (55-75%). In virgin soils intensity of pedoturbations is much less, homogenous type of SMP distribution is not detected in any soil profiles. Furthermore on two virgin forest sites in USA and Russia percentage of soils with initial accumulative type of SMP distribution was 100%. On site in virgin steppe region of Russia - 85% of soils characterized by initial accumulative type and other 15% by not uniform with maximum in the upper 10 cm. Only on one site in forest region of Russia percentage of initial accumulative type of SMP distribution was rather low and even less than on arable soils with moldboard type of plowing - 67%.

  14. Coke-oven by-product modifications at National Steel's Great Lakes Div

    SciTech Connect

    Kalinowsky, R.P. . Great Lakes Division); Platts, M. )

    1994-10-01

    The rebuilt by-products plant, and coal and coke material handling facilities began operation in Nov. 1992. Coal handling facilities were reused with repairs and modifications, such as new vibrating bin bottoms, bin blasters and variable-speed belts with weigh scales for an accurate coal blend. Coke handling consists of two new fixed-blade rack and pinion drive coke plows, new conveyors and screening station. The by-products plant processes 48 million cu ft of coke-oven gas per day through two rehabilitated primary coolers, one of two rehabilitated exhausters, two new tar precipitators in parallel, two new ammonia scrubbers with secondary cooling in series and two rehabilitated light oil scrubbers in series. Environmental facilities include ammonia stills, catalytic ammonia destruction reactors with waste heat boilers and complete gas blanketing for benzene control. All facilities are PLC and DCS controlled with data trending capability. The by-product plant met all performance guarantees without any problems.

  15. Soil Fumigation: Principles and Application Technology

    PubMed Central

    Lembright, H. W.

    1990-01-01

    The principal soil fumigants and their order of discovery are carbon disulfide, chloropicrin, methyl bromide, 1,3-dichloropropene, ethylene dibromide, 1,2-dibromo-3-chloropropane, and methyl isothiocyanate. Biological activity of soil fumigants ranges from limited to broad spectrum. Fumigants diffuse through the continuous soil air space as gases. Physical and chemical characteristics determine diffusion rates, distribution between the soil air and moisture, and sorption onto and into the soil particles. The principal soil factors affecting the efficacy of each treatment are the size and continuity of air space, moisture, temperature, organic matter, and depth of placement. Application can be made overall with tractor injection or plow-sole, or as a row or bed treatment. Treatment for trees is best made in conjunction with tree site backhoeing. PMID:19287772

  16. Measuring Soil Moisture using the Signal Strength of Buried Bluetooth Devices.

    NASA Astrophysics Data System (ADS)

    Hut, R.; Campbell, C. S.

    2015-12-01

    A low power bluetooth Low Energy (BLE) device is burried 20cm into the soil and a smartphone is placed on top of the soil to test if bluetooth signal strength can be related to soil moisture. The smartphone continuesly records and stores bluetooth signal strength of the device. The soil is artifcially wetted and drained. Results show a relation between BLE signal strength and soil moisture that could be used to measure soil moisture using these off-the-shelf consumer electronics. This opens the possibily to develop sensors that can be buried into the soil, possibly below the plow-line. These sensors can measure local parameters such as electric conductivity, ph, pressure, etc. Readings would be uploaded to a device on the surface using BLE. The signal strength of this BLE would be an (additional) measurement of soil moisture.

  17. A method for sampling waste corn

    USGS Publications Warehouse

    Frederick, R.B.; Klaas, E.E.; Baldassarre, G.A.; Reinecke, K.J.

    1984-01-01

    Corn had become one of the most important wildlife food in the United States. It is eaten by a wide variety of animals, including white-tailed deer (Odocoileus virginianus ), raccoon (Procyon lotor ), ring-necked pheasant (Phasianus colchicus , wild turkey (Meleagris gallopavo ), and many species of aquatic birds. Damage to unharvested crops had been documented, but many birds and mammals eat waste grain after harvest and do not conflict with agriculture. A good method for measuring waste-corn availability can be essential to studies concerning food density and food and feeding habits of field-feeding wildlife. Previous methods were developed primarily for approximating losses due to harvest machinery. In this paper, a method is described for estimating the amount of waste corn potentially available to wildlife. Detection of temporal changes in food availability and differences caused by agricultural operations (e.g., recently harvested stubble fields vs. plowed fields) are discussed.

  18. Outflow Characteristics of Total Nitrogen and Total Phosphorous of an Andisol Paddy Field in the Cool-temperate Zone during a Cropping Period

    NASA Astrophysics Data System (ADS)

    Yuto, Matsuura; Eikichi, Shima; Nagamitsu, Maie

    We investigated the water budget and outflow characteristics of total phosphorous (T-P) and total nitrogen (T-N) of an irrigated paddy field on an Andisol in the cool-temperate zone area. Total effluent flux of water from the paddy field during one cropping period was 2192 mm, 1490 mm (ca. 70%) of which flowed out through the downward percolation. The net discharge of T-P and T-N from the paddy field during one cropping period was 0.47 kg/ha and 35.9 kg/ha, respectively, most of which flowed out through downward percolation. Amounts of T-P and T-N discharged through sublayer soil to the ground water with the downward water percolation corresponded to 23% and 80% of those leached out from the plow layer soil, respectively.

  19. Acceleration and Compression of Charged Particle Bunches Using Counter-Propagating Laser Beams

    SciTech Connect

    G. Shvets; N. J. Fisch; A. Pukhov

    2000-10-17

    The nonlinear interaction between counter-propagating laser beams in a plasma results in the generation of large (enhanced) plasma wakes. The two beams need to be slightly detuned in frequency, and one of them has to be ultra-short (shorter than a plasma period). Thus produced wakes have a phase velocity close to the speed of light and can be used for acceleration and compression of charged bunches. The physical mechanism responsible for the enhanced wake generation is qualitatively described and compared with the conventional laser wakefield mechanism. The authors also demonstrate that, depending on the sign of the frequency difference between the lasers, the enhanced wake can be used as a ``snow-plow'' to accelerate and compress either positively or negatively charged bunches. This ability can be utilized in an electron-positron injector.

  20. Tribological behavior of Ti-Al-Si-C-N hard coatings deposited by hybrid arc-enhanced magnetron sputtering

    SciTech Connect

    Wu Guizhi; Ma Shengli; Xu Kewei; Chu, Paul K

    2012-03-15

    Ti-Al-Si-C-N hard coatings are deposited on high speed steel by hybrid arc-enhanced magnetron sputtering, and the hardness, adhesion, and tribological behavior are studied. On account of the nanocomposite structure, the coatings possess hardness of more than 30 GPa. Failure of the coating during the scratch test is due to the buckling and wedge spallation failure mechanism. Compared to Ti-Al-Si-N, the presence of C in the Ti-Al-Si-C-N coatings leads to reduced friction coefficient and wear rate, indicating effective lubrication rendered by amorphous C. According to the wear tracks examined by scanning electron microscopy, the wear mechanism can be explained by plowing abrasion.

  1. Abrasive Wear Study of NiCrFeSiB Flame Sprayed Coating

    NASA Astrophysics Data System (ADS)

    Sharma, Satpal

    2013-10-01

    In the present study, abrasive wear behavior of NiCrFeSiB alloy coating on carbon steel was investigated. The NiCrFeSiB coating powder was deposited by flame spraying process. The microstructure, porosity and hardness of the coatings were evaluated. Elemental mapping was carried out in order to study the distribution of various elements in the coating. The abrasive wear behavior of these coatings was investigated under three normal loads (5, 10 and 15 N) and two abrasive grit sizes (120 and 320 grit). The abrasive wear rate was found to increase with the increase of load and abrasive size. The abrasive wear resistance of coating was found to be 2-3 times as compared to the substrate. Analysis of the scanning electron microscope images revealed cutting and plowing as the material removal mechanisms in these coatings under abrasive wear conditions used in this investigation.

  2. Long-term measurements of CH{sub 4} and N{sub 2}O fluxes in the Colorado short grass steppe

    SciTech Connect

    Mosier, A.R.; Delgado, J.A.

    1995-06-01

    The fluxes of CH{sub 4} and N{sub 2}O and various soil parameters were measured weekly, year-round in grasslands in northeastern Colorado from April, 1990 until the present. Many of the flux measurement sites were imposed upon long-term N fertilization and tillage studies. The studies demonstrate the interannual variations in gas fluxes and show that the winter-time component contribute 15-40% of the total annual N{sub 2}O emissions and CH{sub 4} consumption in these soils. Both tillage and N fertilization 5-13 years earlier increased N{sub 2}O emissions and decreased soil consumption of atmospheric CH{sub 4}. Ecosystem stabilization following disturbance from plowing and N fertilization appears to require 20 to 50 years in this grassland.

  3. Friction and wear characteristics of iron-chromium alloys in contact with themselves and silicon carbide

    NASA Technical Reports Server (NTRS)

    Miyoshi, K.; Buckley, D. H.

    1979-01-01

    Sliding friction experiments were conducted with various iron-chromium alloys in contact with (1) themselves, (2) single crystal silicon carbide disks, and (3) single crystal abrasive grit of silicon carbide. Results indicate the coefficients of friction for the alloys sliding against themselves are between those for pure iron and pure chromium, and are only slightly different with 1, 5, 9, 14, and 19 weight percent chromium in iron. The wear is due, primarily, to shearing, or tearing fracture, of the cohesive bonds in the bulk metal and plowing of the bulk by lumps of wear debris. There are only slight differences in the coefficients of friction for the various alloys when sliding on silicon carbide. The coefficient of friction for the alloys are higher than those for pure iron and pure chromium. Alloy hardening observed in the alloys plays a dominant role in controlling the abrasive friction and wear behavior of the alloys.

  4. Pesticide leaching through sandy and loamy fields - long-term lessons learnt from the Danish Pesticide Leaching Assessment Programme.

    PubMed

    Rosenbom, Annette E; Olsen, Preben; Plauborg, Finn; Grant, Ruth; Juhler, René K; Brüsch, Walter; Kjær, Jeanne

    2015-06-01

    The European Union authorization procedure for pesticides includes an assessment of the leaching risk posed by pesticides and their degradation products (DP) with the aim of avoiding any unacceptable influence on groundwater. Twelve-year's results of the Danish Pesticide Leaching Assessment Programme reveal shortcomings to the procedure by having assessed leaching into groundwater of 43 pesticides applied in accordance with current regulations on agricultural fields, and 47 of their DP. Three types of leaching scenario were not fully captured by the procedure: long-term leaching of DP of pesticides applied on potato crops cultivated in sand, leaching of strongly sorbing pesticides after autumn application on loam, and leaching of various pesticides and their DP following early summer application on loam. Rapid preferential transport that bypasses the retardation of the plow layer primarily in autumn, but also during early summer, seems to dominate leaching in a number of those scenarios. PMID:25771345

  5. The friction and wear of metals and binary alloys in contact with an abrasive grit of single-crystal silicon carbide

    NASA Technical Reports Server (NTRS)

    Miyoshi, K.; Buckley, D. H.

    1979-01-01

    Sliding friction experiments were conducted with various metals and iron-base binary alloys (alloying elements Ti, Cr, Mn, Ni, Rh and W) in contact with single crystal silicon carbide riders. Results indicate that the friction force in the plowing of metal and the groove height (corresponding to the wear volume of the groove) decrease linearly as the shear strength of the bulk metal increases. The coefficient of friction and groove height generally decrease, and the contact pressure increases with an increase in solute content of binary alloys. There appears to be very good correlation of the solute to iron atomic ratio with the decreasing rate of change of coefficient of friction, the decreasing rate of change of groove height and the increasing rate of change of contact pressure with increasing solute content. These rates of change increase as the solute to iron atomic radius ratio increases or decreases from unity.

  6. Evaluation of remote sensing in control of pink bollworm in cotton. [Imperial Valley, Coachella Valley, and Palo Verde Valley, California

    NASA Technical Reports Server (NTRS)

    Lewis, L. N. (Principal Investigator); Coleman, V. B.; Johnson, C. W.

    1974-01-01

    The author has identified the following significant results. This investigation is to evaluate the use of a satellite in monitoring the cotton production regulation program of the State of California as an aid in controlling pink bollworm infestation in the southern deserts of California. Color combined images of ERTS-1 multispectral images simulating color infrared are being used for crop identification. The status of each field (crop, bare, harvested, wet, plowed) is mapped from the imagery and is then compared to ground survey information taken at the time of ERTS-1 overflights. A computer analysis has been performed to compare field and satellite data to a crop calendar. Correlation to date has been 97% for field condition. Actual crop identification varies; cotton identification is only 63% due to lack of full season coverage.

  7. Hydrologic modeling to screen potential environmental management methods for malaria vector control in Niger

    NASA Astrophysics Data System (ADS)

    Gianotti, Rebecca L.; Bomblies, Arne; Eltahir, Elfatih A. B.

    2009-08-01

    This paper describes the first use of Hydrology-Entomology and Malaria Transmission Simulator (HYDREMATS), a physically based distributed hydrology model, to investigate environmental management methods for malaria vector control in the Sahelian village of Banizoumbou, Niger. The investigation showed that leveling of topographic depressions where temporary breeding habitats form during the rainy season, by altering pool basin microtopography, could reduce the pool persistence time to less than the time needed for establishment of mosquito breeding, approximately 7 days. Undertaking soil surface plowing can also reduce pool persistence time by increasing the infiltration rate through an existing pool basin. Reduction of the pool persistence time to less than the rainfall interstorm period increases the frequency of pool drying events, removing habitat for subadult mosquitoes. Both management approaches could potentially be considered within a given context. This investigation demonstrates that management methods that modify the hydrologic environment have significant potential to contribute to malaria vector control in water-limited, Sahelian Africa.

  8. Effects of Particulate Debris Morphology on the Rolling Wear Behavior of All-Steel and Si(Sub 3)N(Sub 4)-Steel Bearing Element Couples

    SciTech Connect

    Adair, J.H.; Mecholsky, J.J., Jr.; Mitchell, D.J.

    1999-01-25

    Rolling contact fatigue experiments were performed on all-steel and hybrid Si{sub 3}N{sub 4}-M50 steel rolling bearing systems using particulate contaminated lubricants. The particulate contaminants used were glycothermally synthesized {alpha}-Al{sub 2}O{sub 3} platelets or Arizona test dust. The effects of contaminant composition and morphology on rolling contact fatigue and wear behavior were explored. The effects of bearing element material properties on fatigue and wear behavior were also examined. Rolling wear behavior is related to bearing component material configuration and the type of particulate contaminant present in the lubricant. Component and particulate material properties such as hardness and elastic modulus are observed to affect rolling wear behavior. Wear mechanisms such as contact stress fatigue, indenting, cutting and plowing are observed.

  9. Application of ecological, geological and oceanographic ERTS-1 imagery to Delaware's coastal resources management

    NASA Technical Reports Server (NTRS)

    Klemas, V. (Principal Investigator); Bartlett, D. S.; Philpot, W. D.; Davis, G. R.; Rogers, R. H.; Reed, L.

    1974-01-01

    The author has identified the following significant results. Data from twelve successful ERTS-1 passes over Delaware Bay have been analyzed with special emphasis on coastal vegetation, land use, current circulation, water turbidity and pollution dispersion. Secchi depth, suspended sediment concentration and transmissivity as measured from helicopters and boats were correlated with ERTS-1 image radiance. Multispectral signatures of acid disposal plumes, sediment plumes and slick were investigated. Ten vegetative cover and water discrimination classes were selected for mapping: (1) forest-land; (2) Phragmites communis; (3) Spartina patens and Distichlis spicata; (4) Spartina alterniflora; (5) cropland; (6) plowed cropland; (7) sand and bare sandy soil; (8) bare mud; (9) deep water; and (10) sediment-laden and shallow water. Canonical analysis predicted good classification accuracies for most categories. The actual classification accuracies were very close to the predicted values with 8 of 10 categories classified with greater than 90% accuracy indicating that representative training sets had been selected.

  10. The content of available mineral phosphorus compounds in chestnut soils of Northern Mongolia upon application of different forms of phosphorite

    NASA Astrophysics Data System (ADS)

    Ubugunov, L. L.; Enkhtuyaa, B.; Merkusheva, M. G.

    2015-06-01

    The effect of different forms of phosphorite (activated and crude ground) of the Burenkhansk deposit on the phosphate status of chestnut soils and the productivity of spring wheat was studied in Northern Mongolia. It was found that the transformation of mineral soil phosphates upon the application of activated phosphorite (together with NK) is similar to that upon superphosphate application, and the available phosphorus concentration is even a gradation higher. The application of crude ground phosphorite helped to preserve the content of mineral phosphates in the soil at the initial level. Optimum concentrations of available phosphorus and the sum of loosely bound and calcium phosphates in the plow horizon were estimated 33-35 mg/kg) and 16-18 mg/100 g, respectively. Under these concentrations, high and sustainable yields of spring wheat were obtained upon application of activated phosphorite.

  11. Strategies for overcoming temporary phytotoxic effects of calcium sulfite applied to agricultural soils

    SciTech Connect

    Ritchey, K.D.; Kinraide, T.B.; Wendell, R.R.; Clark, R.B.; Baligar, V.C.

    1994-12-31

    Calcium sulfite is a major component of scrubber residues produced by lime-based flue gas desulfurization (FGD) processes, widely used in the Ohio River Valley. Preliminary studies have shown that calcium sulfite severely decreased corn plant growth when incorporated into acid soils at moderate rates. Evidence is strong that the toxic effect on plant growth is due to generation of sulfur dioxide in acidic soil. Bioassay methods were used to demonstrate that raising soil pH reduced calcium sulfite toxicity. In solution and in soils, calcium sulfite oxidizes to calcium sulfate (gypsum), which is an agricultural soil amendment useful for increasing calcium levels in acidic subsoils. This potential for oxidation indicates the possibility of incorporating calcium sulfite several months before the crop is sown so that the calcium sulfite will transform to gypsum, which should, because of its relatively high solubility, leach below the plow layer and improve the subsoil.

  12. A physically-based abrasive wear model for composite materials

    SciTech Connect

    Lee, Gun Y.; Dharan, C.K.H.; Ritchie, Robert O.

    2001-05-01

    A simple physically-based model for the abrasive wear of composite materials is presented based on the mechanics and mechanisms associated with sliding wear in soft (ductile) matrix composites containing hard (brittle) reinforcement particles. The model is based on the assumption that any portion of the reinforcement that is removed as wear debris cannot contribute to the wear resistance of the matrix material. The size of this non-contributing portion of the reinforcement is estimated by modeling the three primary wear mechanisms, specifically plowing, interfacial cracking and particle removal. Critical variables describing the role of the reinforcement, such as its relative size and the nature of the matrix/reinforcement interface, are characterized by a single contribution coefficient, C. Predictions are compared with the results of experimental two-body (pin-on drum) abrasive wear tests performed on a model aluminum particulate-reinforced epoxy matrix composite material.

  13. A map of sphingosine 1-phosphate distribution in the spleen

    PubMed Central

    Ramos-Perez, Willy D.; Fang, Victoria; Escalante-Alcalde, Diana; Cammer, Michael; Schwab, Susan R.

    2015-01-01

    Despite the importance of signaling lipids, many questions remain about their function because we have few tools to chart lipid gradients in vivo. Here we describe a sphingosine 1-phosphate (S1P) reporter mouse, and use this mouse to define S1P distribution in the spleen. Surprisingly, the presence of blood does not predict the concentration of signaling-available S1P. Large areas of the red pulp are S1P-low, while S1P can be sensed by cells inside the white pulp near the marginal sinus. Lipid phosphate phosphatase 3 maintains low S1P concentrations in the spleen, and enables efficient marginal zone B cell shuttling. The exquisitely tight regulation of S1P availability may explain how a single lipid can simultaneously orchestrate many immune cell movements. PMID:26502404

  14. The uses of ERTS-1 imagery in the analysis of landscape change. [agriculture, strip mining forests, urban-suburban growth, and flooding in Tennessee, Kentucky, Mississippi, and Alabama

    NASA Technical Reports Server (NTRS)

    Rehder, J. B. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. The analysis of strip mining from ERTS-1 data has resulted in the mapping of landscape changes for the Cumberland Plateau Test Site. Several mapping experiments utilizing ERTS-1 data have been established for the mapping of state-wide land use regions. The first incorporates 12 frames of ERTS-1 imagery for the generalized thematic mapping of forest cover for the state of Tennessee. In another mapping effort, 14 ERTS-1 images have been analyzed for plowed ground signatures to produce a map of agricultural regions for Tennessee, Kentucky, and the northern portions of Mississippi and Alabama. Generalized urban land use categories and transportation networks have been determined from ERTS-1 imagery for the Knoxville Test Site. Finally, through the analysis of ERTS-1 imagery, short-lived phenomena such as the 1973 spring floods on the Mississippi River in western Tennessee, have been detected, monitored, and mapped.

  15. Ultrarelativistic electromagnetic pulses in plasmas

    NASA Technical Reports Server (NTRS)

    Ashour-Abdalla, M.; Leboeuf, J. N.; Tajima, T.; Dawson, J. M.; Kennel, C. F.

    1981-01-01

    The physical processes of a linearly polarized electromagnetic pulse of highly relativistic amplitude in an underdense plasma accelerating particles to very high energies are studied through computer simulation. An electron-positron plasma is considered first. The maximum momenta achieved scale as the square of the wave amplitude. This acceleration stops when the bulk of the wave energy is converted to particle energy. The pulse leaves behind as a wake a vacuum region whose length scales as the amplitude of the wave. The results can be explained in terms of a snow plow or piston-like action of the radiation on the plasma. When a mass ratio other than unity is chosen and electrostatic effects begin to play a role, first the ion energy increases faster than the electron energy and then the electron energy catches up later, eventually reaching the same value.

  16. Microtribological Performance of Metal-doped Molybdenum Disulfide Coatings

    NASA Astrophysics Data System (ADS)

    Stoyanov, Pantcho

    2011-07-01

    The mechanical and tribological properties of pure MoS2, pure Au, Au-MoS2 and Ti-MoS2 coatings were evaluated and examined at a microscopic scale. The metal doped MoS2 coatings had varying metal content, 5-10at% for Ti and 10-90% for Au. Reciprocating sliding wear tests were performed with a range of initial Hertzian contact pressures from 0.41 to 3.5 GPa and in air at two humidity levels (i.e. "low" being 3-5%RH and "high" being 30-40%RH). Titanium and gold were chosen for this study as metal additives due to their positive influence on the mechanical properties of the coating. The friction and wear behavior at the micro-scale were directly compared to tribological properties at the macro-scale, which were performed using an in situ tribometer. Reciprocating micro- and macro- wear tests were performed with spherical diamond tip (with 10 and 50 mum radii) and a sapphire tip (with a radius of 3.175 mm), respectively. The range of initial Hertzian contact pressures for macro-scale (i.e. between 0.41GPa and 1.2GPa) overlapped with that for micro-scale. However, the initial Hertzian contact diameters (2*a) were very different (i.e. 0.8-2.3 mum for micro-scale and 60-180 mum for macro-scale). It was observed that the small addition of Ti or Au to MoS2 improved the microtribological properties (i.e. lower friction and less wear) compared to pure MoS2 coatings. The improved microtribological properties with metal additions were attributed to an increase in the mechanical properties, decrease in adhesion, and a decrease in the interfacial shear strength. In terms of the different length scales, lower steady state friction was observed for macrotribology compared to microtribology. The higher friction at the micro- scale was explained by the greater adhesion effects and additional velocity accommodation modes (e.g. microplowing or plowing). The microplowing or plowing at the microscopic scale was attributed to the tip roughness and the inability to sustain a stable

  17. Observations on the grinding of alumina with variations in belt speed, load, sample rotation, and grinding fluids

    SciTech Connect

    Schwartz, C.J.; Bahadur, S.

    1998-07-01

    The volume of material removed in the grinding of alumina on a diamond-impregnated grinding belt was studied. Four grinding process parameters were tested: belt speed, normal load at the pin's contact surface, sample rotation during grinding, and grinding fluid. The results showed that at low loads the belts speed did not have a significant effect on material removal rates; however, the material removal rate decreased at higher loads combined with higher speeds. It decreased, in particular, when the sample was also rotated. Of the fluids used, the 50% ethylene glycol--50% water mixture produced the highest material removal rates while the lowest were produced by biodegradable soybean oil. The test conditions that produced high temperatures at the contact surface contributed to plowing as opposed to cutting and resulted in reduced material removal rates. The reasons for these variations were investigated by scanning electron microscopy of the surfaces, which revealed evidence of plastic deformation and temperature rise during grinding.

  18. Effects of plant densities and management of purple nutsedge on sugarcane yield and effect of growth stages and main way of herbicides contact and absorption on the control of tubers.

    PubMed

    Durigan, Julio Cezar

    2005-01-01

    Field experiments carried out with Cyperus rotundus L. at low (58-246), medium (318-773), and high (675-1198 shoots/m2) densities showed sugarcane yield reductions of 13.5, 29.3, and 45.2%, respectively in relation to the control. In the second field experiment, the integration of a mechanic method with two sequences of plowing and disking operations in the dry season, and complementary applications of trifloxysulfuron-sodium + ametrine and sulfentrazone (rainy season) was studied. Average of the chain connected to original shoot showed 92, 95, and 65% of reduction with trifloxysulfuron-sodium + ametrine and surfactant, at the application stages "early," preflowering, and full flowering, respectively. PMID:15656168

  19. MHD Modelling of Flow Phenomena during the Impulse Plasma Deposition Process

    NASA Astrophysics Data System (ADS)

    Rabiński, M.; Zdunek, K.

    2008-03-01

    The paper presents recent computational studies of plasma dynamics in a coaxial accelerator used in surface engineering for Impulse Plasma Deposition (IPD). In our earlier studies we proposed a schematic pattern of a discharge region and a physical model of dynamic phenomena in the IPD accelerator with a tubular external electrode. The simplified snow plow code of our previous studies assumes that all the swept up mass is compressed into an infinitely thin layer immediately behind the shock. In the presented work the complete two-dimensional two-fluid magnetohydrodynamic model has been applied to investigate the sweeping of the working gas by the moving layer as well as the details of phenomena that take place behind a current sheet.

  20. Semi-automatic crop inventory from sequential ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Johnson, C. W.; Coleman, V. B.

    1973-01-01

    The detection of a newly introduced crop into the Imperial (California) Valley by sequential ERTS-1 imagery is proving that individual crop types can be identified by remote sensing techniques. Initial results have provided an extremely useful product for water agencies. A system for the identification of field conditions enables the production of a statistical summary within two to three days of receipt of the ERTS-1 imagery. The summary indicates the total acreage of producing crops and irrigated planted crops currently demanding water and further indicates freshly plowed fields that will be demanding water in the near future. Relating the field conditions to the crop calendar of the region by means of computer techniques will provide specific crop identification for the 8000 plus fields.

  1. [Effects of sulfur- and polymer-coated controlled release urea fertilizers on wheat yield and quality and fertilizer nitrogen use efficiency].

    PubMed

    Ma, Fu-Liang; Song, Fu-Peng; Gao, Yang; Zou, Peng

    2012-01-01

    A field experiment was conducted to study the effects of sulfur- and polymer-coated controlled release urea fertilizers on wheat yield and its quality, plow layer soil inorganic nitrogen (N) contents, and fertilizer N use efficiency. Compared with traditional urea fertilizer, both sulfur- and polymer-coated controlled release urea fertilizers increased the grain yield by 10.4%-16.5%, and the grain protein and starch contents by 5.8%-18.9% and 0.3%-1.4%, respectively. The controlled release urea fertilizers could maintain the topsoil inorganic N contents to meet the N requirement for the wheat, especially during its late growth stage. In the meantime, the fertilizer N use efficiency was improved by 58.2%-101.2%. Polymer-coated urea produced better wheat yield and higher fertilizer N use efficiency, compared with sulfur-coated controlled release urea. PMID:22489481

  2. Tribological properties of silicon carbide in metal removal process

    NASA Technical Reports Server (NTRS)

    Miyoshi, K.; Buckley, D. H.

    1980-01-01

    This paper reviews material properties of adhesion, friction and wear of single-crystal silicon carbide in contact with metals and alloys involved in a metal removal process such as grinding. The tribological properties in the metal removal processes are divided into properties which remove metal by adhesion between sliding surfaces, and metal removal by silicon carbide sliding against a metal, indenting it, and plowing a series of grooves or furrows. The paper also deals with fracture and deformation characteristics of the silicon carbide surface; the adhesion, friction and metal transfer to silicon carbide is related to the relative chemical activity of the metals. Atomic size and content of alloying elements play a dominant role in controlling adhesion and friction properties of alloys. The friction and abrasive wear decrease as the shear strength of the bulk metal increases.

  3. Ground-water quality near a sewage-sludge recycling site and a landfill near Denver, Colorado

    USGS Publications Warehouse

    Robson, Stanley G.

    1977-01-01

    The Metropolitan Denver Sewage Disposal District and the city and county of Denver operate a sewage-sludge recycling site and a landfill in an area about 15 miles (24 kilometers) east of Denver. The assessment of the effects of these facilities on the ground-water system indicated that five wells perforated in alluvium were found to have markedly degradedd water quality. One well is located in the landfill and water that was analyzed was obtained from near the base of the buried refuse, two others are located downgradient and near sewage-sludge burial areas, and the remaining two are located near stagnant surface ponds. Concentrations of nitrate in wells downgradient from fields where sludge is plowed into the soil were higher than background concentrations due to the effects of the sludge disposal. No evidence of water-quality degradation was detected in deeper wells perforated in the bedrock formations. (Woodard-USGS)

  4. A summary of Viking sample-trench analyses for angles of internal friction and cohesions

    NASA Technical Reports Server (NTRS)

    Moore, H. J.; Clow, G. D.; Hutton, R. E.

    1982-01-01

    Analyses of sample trenches excavated on Mars, using a theory for plowing by narrow blades, provide estimates of the angles of internal friction and the cohesions of the Martian surface materials. Angles of internal friction appear to be the same as those of many terrestrial soils because they are generally between 27 degrees and 39 degrees. Drift material, at the Lander 1 site, has a low angle of internal friction (near 18 degrees). All the materials excavated have low cohesions, generally between 0.2 and 10 kPa. The occurrence of cross bedding, layers of crusts, and blocky slabs shows that these materials are heterogeneous and that they contain planes of weakness. The results reported here have significant implications for future landed missions, Martian eolian processes, and interpretation of infrared temperatures.

  5. An unremembered diversity: mixed husbandry and the American grasslands.

    PubMed

    Sylvester, Kenneth; Cunfer, Geoff

    2009-01-01

    The Green Revolution of the 1960s brought about a dramatic rise in global crop yields. But, as most observers acknowledge, this has come at a considerable cost to biodiversity. Plant breeding, synthetic fertilizers, and mechanization steadily narrowed the number of crop varieties commercially available to farmers and promoted fencerow-to-fencerow monocultures. Many historians trace the origins of this style of industrialized agriculture to the last great plow-up of the Great Plains in the 1920s. In the literature, farms in the plains are often described metaphorically as wheat factories, degrading successive landscapes. While in many ways these farms were a departure from earlier forms of husbandry in the American experience, monocultures were quite rare during the early transformation of the plains. Analysis of a large representative sample, based on manuscript agricultural censuses and involving twenty-five townships across the state of Kansas, demonstrates that diverse production reached even the most challenging of plains landscapes. PMID:19839113

  6. German mining equipment

    SciTech Connect

    Not Available

    1993-10-01

    The German mining equipment industry developed to supply machines and services to the local mining industry, i.e., coal, lignite, salt, potash, ore mining, industrial minerals, and quarrying. The sophistication and reliability of its technology also won it worldwide export markets -- which is just as well since former major domestic mining sectors such as coal and potash have declined precipitously, and others such as ore mining have all but disappeared. Today, German mining equipment suppliers focus strongly on export sales, and formerly unique German mining technologies such as continuous mining with bucket wheel excavators and conveyors for open pits, or plowing of underground coal longwalls are widely used abroad. The status of the German mining equipment industry is reviewed.

  7. Timing of x-ray burst from X-pinch

    SciTech Connect

    Zhao, Shen; Zhang, Ran; Zhu, Xinlei; Zou, Xiaobing; Wang, Xinxin

    2015-06-15

    The x-ray burst timings of X-pinches, T{sub XB}, made using eight different wires for different current were measured. The results showed that a higher current makes a shorter T{sub XB} for a given X-pinch wire. In other words, T{sub XB} scales linearly with the line mass density for a given current. Based on the snow-plow model for Z-pinch plasma, it was derived that for a given X-pinch wire the integral of the current over time from zero to T{sub XB} is constant, i.e., ∫{sub 0}{sup T{sub X}{sub B}}i(t)⋅dt=const.. This theoretically derived relation was confirmed by our experiments.

  8. Impact of reclamation treatment on the biological activity of soils of the solonetz complex in Western Siberia

    NASA Astrophysics Data System (ADS)

    Berezin, L. V.; Khamova, O. F.; Paderina, E. V.; Gindemit, A. M.

    2014-11-01

    The abundance and activity of the soil microflora were studied in a field experiment with the use of green manure crops to assess the impact of reclamation measures on the biological activity of soils of the solonetz complex. The number of microorganisms in the plow soil horizon increased in the background of the green fallows as compared to the black ones. Coefficients of mineralization, immobilization, and transformation of organic compounds were calculated for different variants of the soil treatment. The value of the mineralization coefficient indicates the intense decomposition of the green manure that entered the soil. In the first year, peas were actively decomposed, while oats, in the second year (aftereffect). The activity of the soil enzymes (invertase, urease, and catalase) was determined. A close relationship between the catalase activity and the intensity of the microbiological processes in the soils was revealed.

  9. The influence of pine forests of different ages on the biological activity of layland soils in the middle Angara River basin

    NASA Astrophysics Data System (ADS)

    Sorokina, O. A.; Sorokin, N. D.

    2007-05-01

    The influence of pine forests of different ages (from 25 to 85 years) restoring on old plow land soils is reflected in the biological processes proceeding in them. The drastic decrease in the absolute and relative number of actinomycetes, along with an increase of the fungal population in the microbial complexes of the soils (within the whole profiles), indicates that the microbocenoses acquire “forest” properties. In the soils under the younger pine forests, the processes of microbiological mineralization and specific respiration activity are more active than in the soils under the older pine forests. With the age of the pine forests, the soil profiles become more differentiated according to the eluvial-illuvial type.

  10. An Unremembered Diversity: Mixed Husbandry and the American Grasslands

    PubMed Central

    SYLVESTER, KENNETH; CUNFER, GEOFF

    2009-01-01

    The Green Revolution of the 1960s brought about a dramatic rise in global crop yields. But, as most observers acknowledge, this has come at a considerable cost to biodiversity. Plant breeding, synthetic fertilizers, and mechanization steadily narrowed the number of crop varieties commercially available to farmers and promoted fencerow-to-fencerow monocultures. Many historians trace the origins of this style of industrialized agriculture to the last great plow-up of the Great Plains in the 1920s. In the literature, farms in the plains are often described metaphorically as wheat factories, degrading successive landscapes. While in many ways these farms were a departure from earlier forms of husbandry in the American experience, monocultures were quite rare during the early transformation of the plains. Analysis of a large representative sample, based on manuscript agricultural censuses and involving twenty-five townships across the state of Kansas, demonstrates that diverse production reached even the most challenging of plains landscapes. PMID:19839113

  11. Pulverizer tramp iron problems affect coal switching at Union Electric`s Labadie Plant

    SciTech Connect

    Fife, P.A.; Mahr, D.

    1997-07-01

    Union Electric`s Labadie Plant, is a 2400 MWe (4 x 600) coal-fired power generating plant. It is located 35 miles west of St. Louis. The four units were commissioned between 1970 and 1973. Major plant equipment is summarized. Coal is delivered via unit-trains and stacked by two tower style, radial stackers. The plant annually consumes approximately six million tons of coal. In 1981, a coal blending system was retrofitted to the plant. This system features a traveling stacker on an elevated berm and rotary plow reclaimers. The coal blending system feeds all four units. Bins weigh feeders, and belt scales precisely control blending proportions. The blending system has served the plant, increasing fuel flexibility in the types and blends of coal that can be used.

  12. Subtropical iceberg scours: Tracking the path of meltwater in the deglacial North Atlantic

    NASA Astrophysics Data System (ADS)

    Hill, J. C.; Condron, A.

    2015-12-01

    Over 700 individual iceberg scours have been identified in seafloor bathymetry spanning the southern U.S. Atlantic margin, from Cape Hatteras, North Carolina to the Florida Keys, in water depths from 170-380m. These iceberg scours represent the plowing path of iceberg keels transported southward along the margin in a cold, coastal boundary current derived from the Laurentide Ice Sheet. Despite limited regional multibeam bathymetry data, the scours are traceable along the seafloor for >30 km and exhibit characteristic morphology of iceberg keel marks documented along glaciated continental margins. Many of the scours are flanked by lateral berms that are several meters high and often terminate in semi-circular pits ringed by several meter high ridges (i.e. grounding pits or iceberg plow ridges). The scours decrease in size and abundance moving southward, in accordance with increased iceberg melting farther from the ice calving margin. For example, the scours offshore of South Carolina (~32.5°N) are ~10-100m wide and incised 10-20m into the sediment, whereas scours off the Florida margin (31°N- 24.5°N) are narrower (10-50m wide) and incised 2-5m into the sea floor. Icebergs at these subtropical latitudes would likely have been comparable in size (up 300 m thick) to those calving from the modern-day Greenland Ice Sheet margin. Results from numerical simulations using MITgcm, a high-resolution, eddy-permitting, coupled ice-ocean model configured for the LGM suggest that cold, freshwater and small (≤90m thick) icebergs could have seasonally drifted to South Carolina, but iceberg transport to southern Florida requires much larger (5Sv) meltwater floods to overcome the northward flowing Gulf Stream. These meltwater flood events would most likely have been short-lived (<1 yr), but may have diverted a significant volume of freshwater away from the subpolar regions into the subtropical North Atlantic.

  13. Verification of radiocesium decontamination from farmlands by plants in Fukushima.

    PubMed

    Kobayashi, Daisuke; Okouchi, Toshiyasu; Yamagami, Mutsumi; Shinano, Takuro

    2014-01-01

    The purpose of this study was to verify radiocesium decontamination from Fukushima farmland by plants and to screen plants useful for phytoremediation. Thirteen species from three families (Asteraceae, Fabaceae, and Poaceae) of crops were grown in shallow and deeply cultivated fields (0-8 and 0-15 cm plowing, respectively). To change plowing depth was expected to make different contacting zone between root system and radiocesium in soil. The radioactivity values of the plants due to the radiocesium ¹³⁴Cs and ¹³⁷Cs were 22-179 and 29-225 Bq kg dry weight⁻¹, respectively. The ¹³⁴Cs and ¹³⁷Cs transfer factors for plants grown in the shallow field ranged from 0.021 to 0.12 and fro 0.019 to 0.13, respectively, with the geometric means of 0.051 and 0.057, respectively. The ¹³⁴Cs and ¹³⁷Cs transfer factors for plants grown in the deep field ranged from 0.019 to 0.13 and from 0.022 to 0.13, respectively, with the geometric means of 0.045 and 0.063, respectively. Although a reducing ratio was calculated to evaluate the decrease in radiocesium from contaminated soil during cultivation (i.e., phytoremediation ability), no plant species resulted in a remarkable decrease in radiocesium in soil among the tested crops. These results should be followed up for several years and further analyses are required to evaluate whether the phytoremediation technique is applicable to radioactively contaminated farmlands. PMID:24292804

  14. Characteristics of dissolved carbon change in irrigation water

    NASA Astrophysics Data System (ADS)

    Akaike, Y.; Kunishio, A.; Kawamoto, Y.; Murakami, H.; Iwata, T.

    2012-12-01

    It is necessary to estimate carbon emission from soil for understanding carbon cycle processes in cultivated fields. Since irrigation water is introduced into a typical rice paddy field, one part of emitted carbon content from soil were trapped by water and dissolved in it, and dissolved carbon content outflows from the field at the drainage moment. In this study, we continuously and regularly analyzed dissolved carbon content of irrigation water and investigated seasonal variation of efflux of carbon from a paddy field. Experimental site is located reclaimed land in the southern part of Okayama Prefecture, Japan. And rice cropping cultivation has continued in a similar method every year. Intermittent irrigation water managements, or 3 days flooded and 4 days drained condition, were carried out during almost all the period of rice cultivated term. Irrigation water was sampled every flooding and drainage days. Inorganic carbon (IC) concentration was measured with total carbon (TC) analyzer (TOC-V/CSH, SHIMAZU). Amount of dissolved carbon in irrigation water was calculated from product of the carbon concentration and water levels. The experimental paddy field was divided into two areas, and two bottle of water were sampled from each area. In order to investigate what impact is brought on the annual carbon cycle by the difference of disposal management of residual biomass after the harvest, residual biomass was burned and plowed into soil at the one area on 29th Nov., 2011, and residue was not burned and directly plowed into soil at the other area as usual. IC during cultivated term in 2011 and 2012 in both area gradually increased day by day for every flooded periods. And IC showed distinct diurnal variations with lower value in the daytime than at night, it is because of photosynthetic activities by aquatic algae in the irrigation water.

  15. Carbon decomposition process of the residual biomass in the paddy soil of a single-crop rice field

    NASA Astrophysics Data System (ADS)

    Okada, K.; Iwata, T.

    2014-12-01

    In cultivated fields, residual organic matter is plowed into soil after harvest and decaying in fallow season. Greenhouse gases such as CO2 and CH4 is generated by the decomposition of the substantial organic matter and released into the atmosphere. In some fields, open burning is carried out by tradition, when carbon in residual matter is released into atmosphere as CO2. However, burning effect on carbon budget between crop lands and atmosphere is not entirely considered yet. In this study, coarse organic matter (COM) in paddy soil of a single-crop rice field was sampled on regular intervals between January, 2011 and August, 2014 The amount of carbon release from residual matter was estimated by analyzing of the variations in carbon content of COM. Effects of soil temperature (Ts) and soil water content (SWC) at the paddy field on the rate of carbon decomposition was investigated. Though decreasing rate of COM was much smaller in winter season, it is accelerated at the warming season between April and June every year. Decomposition was resisted for next rice cultivated season despite of highest soil temperature. In addition, the observational field was divided into two areas, and three time open burning experiments were conducted in November, 2011, 2012, and 2013. In each year, three sampling surveys, or plants before harvest and residuals before and after the burning experiment, were done. From these surveys, it is suggested that about 48±2% of carbon contents of above-ground plant was yield out as grain by harvest, and about 27±2% of carbon emitted as CO2 by burning. Carbon content of residuals plowed into soil after the harvest was estimated 293±1 and 220±36gC/m2 in no-burned and burned area, respectively, based on three-years average. It is estimated that 70 and 60% of the first input amount of COM was decomposed after a year in no-burned and burned area, respectively.

  16. Nutrient and sediment losses under simulated rainfall following manure incorporation by different methods.

    PubMed

    Little, Joanne L; Bennett, D Rodney; Miller, Jim J

    2005-01-01

    Incorporation of manure into cultivated soils is generally recommended to minimize nutrient losses. A 3-yr study was conducted to evaluate sediment and nutrient losses with different tillage methods (moldboard plow, heavy-duty cultivator, double disk, and no-incorporation) for incorporation of beef cattle manure in a silage barley (Hordeum vulgare L.) cropping system. Runoff depths, sediment losses, and surface and subsurface nutrient transfers were determined from manured and unmanured field plots at Lethbridge, Alberta, Canada. A Guelph rainfall simulator was used to generate 30 min of runoff. Sediment losses among our tillage treatments (137.4-203.6 kg ha(-1)) were not significantly different due to compensating differences in runoff depths. Mass losses of total phosphorus (TP) and total nitrogen (TN) in surface runoff were greatest from the no-incorporation (NI) treatments, with reductions in TP loads of 14% for double disk (DD), 43% for cultivator (CU), and 79% for moldboard plow (MP) treatments. Total N load reductions in 2002 were 26% for DD, 70% for CU, and 95% for MP treatments compared to the NI treatments. Nutrient losses following incorporation of manure with the DD or CU methods were not significantly different from the NI treatments. Manure treatments generally had lower runoff depths and sediment losses, and higher phosphorus and nitrogen losses than the control treatments. Subsurface concentrations of NH4-N, NO3-N, and TN were greatest from the MP treatments, whereas subsurface phosphorus concentrations were not affected by tillage method. Tillage with a cultivator or double disk minimized combined surface and subsurface nutrient losses immediately after annual manure applications. PMID:16151240

  17. Disturbance alters the phylogenetic composition and structure of plant communities in an old field system.

    PubMed

    Dinnage, Russell

    2009-01-01

    The changes in phylogenetic composition and structure of communities during succession following disturbance can give us insights into the forces that are shaping communities over time. In abandoned agricultural fields, community composition changes rapidly when a field is plowed, and is thought to reflect a relaxation of competition due to the elimination of dominant species which take time to re-establish. Competition can drive phylogenetic overdispersion, due to phylogenetic conservation of 'niche' traits that allow species to partition resources. Therefore, undisturbed old field communities should exhibit higher phylogenetic dispersion than recently disturbed systems, which should be relatively 'clustered' with respect to phylogenetic relationships. Several measures of phylogenetic structure between plant communities were measured in recently plowed areas and nearby 'undisturbed' sites. There was no difference in the absolute values of these measures between disturbed and 'undisturbed' sites. However, there was a difference in the 'expected' phylogenetic structure between habitats, leading to significantly lower than expected phylogenetic diversity in disturbed plots, and no difference from random expectation in 'undisturbed' plots. This suggests that plant species characteristic of each habitat are fairly evenly distributed on the shared species pool phylogeny, but that once the initial sorting of species into the two habitat types has occurred, the processes operating on them affect each habitat differently. These results were consistent with an analysis of correlation between phylogenetic distance and co-occurrence indices of species pairs in the two habitat types. This study supports the notion that disturbed plots are more clustered than expected, rather than 'undisturbed' plots being more overdispersed, suggesting that disturbed plant communities are being more strongly influenced by environmental filtering of conserved niche traits. PMID:19763265

  18. Effect of the molecular weight on deformation states of the polystyrene film by AFM single scanning.

    PubMed

    Sun, Yang; Yan, Yongda; Liang, Yingchun; Hu, Zhenjiang; Zhao, Xuesen; Sun, Tao; Dong, Shen

    2013-01-01

    Nanobundles patterns can be formed on the surface of most thermoplastic polymers when the atomic force microscope (AFM)-based nanomechanical machining method is employed to scratch their surfaces. Such patterns are reviewed as three-dimensional sine-wave structures. In the present study, the single-line scratch test is used firstly to study different removal states of the polystyrene (PS) polymer with different molecular weights (MWs). Effects of the scratching direction and the scratching velocity on deformation of the PS film and the state of the removed materials are also investigated. Single-wear box test is then employed to study the possibility of forming bundle structures on PS films with different MWs. The experimental results show that the state between the tip and the sample plays a key role in the nano machining process. If the contact radius between the AFM tip and the polymer surface is larger than the chain end-to-end distance, it is designated as the "cutting" state that means the area of both side ridges is less than the area of the groove and materials are removed. If the contact radius is less than the chain end-to-end distance, it is designated as the "plowing" state that means the area of both side ridges is larger than the area of the groove and no materials are removed at all. For the perfect bundles formation on the PS film, the plowing state is ideal condition for the larger MW polymers because of the chains' entanglement. PMID:23229843

  19. Standardization of a Volumetric Displacement Measurement for Two-Body Abrasion Scratch Test Data Analysis

    NASA Technical Reports Server (NTRS)

    Street, K. W. Jr.; Kobrick, R. L.; Klaus, D. M.

    2011-01-01

    A limitation has been identified in the existing test standards used for making controlled, two-body abrasion scratch measurements based solely on the width of the resultant score on the surface of the material. A new, more robust method is proposed for analyzing a surface scratch that takes into account the full three-dimensional profile of the displaced material. To accomplish this, a set of four volume- displacement metrics was systematically defined by normalizing the overall surface profile to denote statistically the area of relevance, termed the Zone of Interaction. From this baseline, depth of the trough and height of the plowed material are factored into the overall deformation assessment. Proof-of-concept data were collected and analyzed to demonstrate the performance of this proposed methodology. This technique takes advantage of advanced imaging capabilities that allow resolution of the scratched surface to be quantified in greater detail than was previously achievable. When reviewing existing data analysis techniques for conducting two-body abrasive scratch tests, it was found that the ASTM International Standard G 171 specified a generic metric based only on visually determined scratch width as a way to compare abraded materials. A limitation to this method was identified in that the scratch width is based on optical surface measurements, manually defined by approximating the boundaries, but does not consider the three-dimensional volume of material that was displaced. With large, potentially irregular deformations occurring on softer materials, it becomes unclear where to systematically determine the scratch width. Specifically, surface scratches on different samples may look the same from a top view, resulting in an identical scratch width measurement, but may vary in actual penetration depth and/or plowing deformation. Therefore, two different scratch profiles would be measured as having identical abrasion properties, although they differ

  20. Stellar Interlopers Caught Speeding Through Space

    NASA Technical Reports Server (NTRS)

    2009-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1 Figure 2 Figure 3 Figure 4 Click on individual image for larger view

    Resembling comets streaking across the sky, these four speedy stars are plowing through regions of dense interstellar gas and creating brilliant arrowhead structures and trailing tails of glowing gas.

    These bright arrowheads, or bow shocks, can be seen in these four images taken with NASA's Hubble Space Telescope. The bow shocks form when the stars' powerful stellar winds, streams of matter flowing from the stars, slam into surrounding dense gas. The phenomenon is similar to that seen when a speeding boat pushes through water on a lake.

    The stars in these images are among 13 runaway stars spotted by Hubble's Advanced Camera for Surveys. The stars appear to be young, just millions of years old. Their ages are based on their colors and the presence of strong stellar winds, a signature of youthful stars.

    Depending on their distance from Earth, the bullet-nosed bow shocks could be 100 billion to a trillion miles wide (the equivalent of 17 to 170 solar system diameters, measured out to Neptune's orbit). The bow shocks indicate that the stars are moving fast, more than 180,000 kilometers an hour (more than 112,000 miles an hour) with respect to the dense gas they are plowing through. They are traveling roughly five times faster than typical young stars, relative to their surroundings.

    The high-speed stars have traveled far from their birth places. Assuming their youthful phase lasts only a million years and they are moving at roughly 180,000 kilometers an hour, the stars have journeyed 160 light-years.

    The Hubble observations were taken between October 2005 and July 2006.

  1. Effects of agricultural land-management practices on water quality in northeastern Guilford County, North Carolina, 1985-90

    USGS Publications Warehouse

    Harned, D.A.

    1994-01-01

    The effects of different agricultural land- management practices on sediment, nutrients, and selected pesticides in surface water, and on nutrients and pesticides in ground water were studied in four small basins in the Piedmont of North Carolina. The basins included two adjacent basins in row-crop fields, a mixed land-use basin, and a forested basin. One of the row-crop fields was farmed using conservation land-management practices, including strip cropping, contour plowing, field borders, and grassed waterways. The other field was farmed using standard land- management practices, including continuous cropping, straight-row plowing, and ungrassed waterways. The sediment yield for the standard land-management basin was 2.3 times that for the conservation land-management basin, 14.1 times that for the mixed land-use basin, and 19.5 times that for the forested basin. Nutrient concentra- tions in surface water from the row-crop and mixed land-use basins were higher than those in surface water for the forested basin. Nutrient concentra- tions in soil water and ground water beneath the row-crop basins were lower than those in surface- water runoff for these basins. The lowest nutrient concentrations measured in the row-crop basins generally were in soil-water samples collected just below the root zone (3-foot depth) and in ground water. No significant differences in pesticide concentrations were identified between the surface-water runoff from the standard land- management basin and that from the conservation land-management basin. Concentrations of the soil pesticides isopropalin and flumetralin were higher in the standard land-management basin than in the conservation land-management basin.

  2. New technological methods for protecting underground waters from agricultural pollution

    NASA Astrophysics Data System (ADS)

    Mavlyanov, Gani

    2015-04-01

    The agricultural production on the irrigated grounds can not carry on without mineral fertilizers, pesticides and herbicides. Especially it is shown in Uzbekistan, in cultivation of cotton. There is an increase in mineralization, rigidity, quantity of heavy metals, phenols and other pollutions in the cotton fields. Thus there is an exhaustion of stocks of fresh underground waters. In the year 2003 we were offered to create the ecological board to prevent pollution to get up to a level of subsoil waters in the top 30 centimeter layer of the ground. We carried out an accumulation and pollution processing. This layer possesses a high adsorbing ability for heavy metals, mineral oil, mineral fertilizers remnants, defoliants and pesticides. In order to remediate a biological pollution treatment processing should be take into account. The idea is consisted in the following. The adsorption properties of coal is all well-known that the Angren coal washing factories in Tashkent area have collected more than 10 million tons of the coal dust to mix with clays. We have picked up association of anaerobic microorganisms which, using for development, destroys nutrients of coal waste pollutions to a harmless content for people. Coal waste inoculation also are scattered by these microorganisms on the field before plowing. Deep (up to 30 cm) plowing brings them on depth from 5 up to 30 cm. Is created by a plough a layer with necessary protective properties. The norm of entering depends on the structure of ground and the intensity of pollutions. Laboratory experiments have shown that 50% of pollutions can be treated by the ecological board and are processed up to safe limit.

  3. Evaluating Resin-Dentin Bond by Microtensile Bond Strength Test: Effects of Various Resin Composites and Placement Techniques

    PubMed Central

    Moosavi, Horieh; Maleknejad, Fatemeh; Forghani, Maryam; Afshari, Elham

    2015-01-01

    Objectives: This in vitro study evaluated the microtensile bond strength (MTBS) of a methacrylate-based compared to a silorane-based resin composite in Class I cavity using different placement techniques. Materials and Methods: Class I cavities with dimension of (4 mm long, 4 mm wide, 3 mm deep) were prepared in extracted sound human molars. The teeth were randomly divided into six groups. The first three groups were filled with Filtek P90 using three methods of insertion; bulk, incremental and snow-plow, and the remaining three groups were filled with Clearfil AP-X using the same three placement techniques. After 24 hours of storage in water at 37°C, the specimens were thermocycled to 1000 cycles. Specimens were prepared for MTBS testing by creating bonded beams obtained from the pulpal floor. Statistical analysis used: Statistical analyses of data were performed by two-way ANOVA/Tukey (α=.05). Results: The experiment showed significant differences between the two resin composites with regard to filling techniques (P<0.05). The MTBS was significantly higher in each of Filtek P90 subgroup compared to Clearfil AP-X ones (P<0.05). With respect to filling technique in both resin composites, bulk insertion showed the significantly lowest MTBS (P<0.05), while no significant difference was found between the outcome of incremental and snow-plow techniques (P>0.05). Conclusion: Silorane-based resin composite as opposed to methacrylate based resin composite and layering placements in contrast to bulk filling method had higher microtensile bond strength. PMID:26966466

  4. Fabrication of Conductive Paths on a Fused Deposition Modeling Substrate using Inkjet Deposition

    SciTech Connect

    Zhou, Wenchao; List, III, Frederick Alyious; Duty, Chad E.; Babu, Sudarsanam Suresh

    2015-01-15

    Inkjet deposition is one of the most attractive fabrication techniques for producing cost efficient and lightweight electronic devices on various substrates with low environmental impact. Fused Deposition Modeling (FDM) is one of the most used and reliable additive manufacturing processes by extrusion of wire-shaped thermoplastic materials, which provides an opportunity for embedding printed electronics into mechanical structures during the building process and enables the design of compact smart structures that can sense and adapt to their own state and the environment. This paper represents one of the first explorations of integrating inkjet deposition of silver nanoparticle inks with the FDM process for making compact electro-mechanical structures. Three challenges have been identified and investigated, including the discontinuity of the printed lines resulting from the irregular surface of the FDM substrate, the non-conductivity of the printed lines due to the particle segregation during the droplet drying process, and the slow drying process caused by the skinning effect . Two different techniques are developed in this paper to address the issue of continuity of the printed lines, including surface ironing and a novel thermal plow technique that plows a channel in the FDM substrate to seal off the pores in the substrate and contain the deposited inks. Two solutions are also found for obtaining conductivity from the continuous printed lines, including porous surface coating and using a more viscous ink with larger nanoparticle size. Then the effects of the printing and post-processing parameters on the conductivity are examined. It is found that post-processing is a dominant factor in determining the conductivity of the printed lines.

  5. Patellar subluxation. A recent history.

    PubMed

    Hughston, J C

    1989-04-01

    For 15 years (1955 to 1970), I was plowing "new ground" pretty much by myself. When you plow behind an old mule and hit a stump hole full of cottonmouth moccasins, you have to get on the move in a hurry and figure out some solution to the predicament or you won't get your corn planted. So, I was not treating the overweight, knock-kneed, loose-jointed, teenaged girl, but the young boy or girl who thought that he or she was an athlete and had dreams of being a star. If rehabilitation did not work, then I thought a lateral release, an Elmslie, and nothing short of a full reconstruction would solve the problem. One had to develop as much vastus medialis obliquus power as this dysplastic muscle could generate, had to transfer the strong vastus lateralis to a more central pull, and, with the distal reconstruction, correct any patella alta and Q-angle abnormality. One had to give the knee every possible advantage in order to serve an athlete. As Hippocrates so wisely noted, one needed to study the athlete to know, with appropriate modifications, what is best for every patient, young or old. In the late 1960s and early 1970s, many fine young orthopedists were stimulated by the information of the AAOS postgraduate courses in sports medicine. They, after having gained further through their own experiences, have become the major contributors to our increasing knowledge of the patellofemoral joint, especially in athletes, and many of these fine "young" (now a little older) orthopedists are now the contributors to this issue. They are giving you their experiences, knowledge, and lessons. A close and repeated study of their information must be combined with compassion for your patient. Then, only experience will develop the desired fine tuning. PMID:2752433

  6. Arteriovenous extracorporeal lung assist allows for maximization of oscillatory frequencies: a large-animal model of respiratory distress

    PubMed Central

    Muellenbach, Ralf M; Kuestermann, Julian; Kredel, Markus; Johannes, Amélie; Wolfsteiner, Ulrike; Schuster, Frank; Wunder, Christian; Kranke, Peter; Roewer, Norbert; Brederlau, Jörg

    2008-01-01

    Background Although the minimization of the applied tidal volume (VT) during high-frequency oscillatory ventilation (HFOV) reduces the risk of alveolar shear stress, it can also result in insufficient CO2-elimination with severe respiratory acidosis. We hypothesized that in a model of acute respiratory distress (ARDS) the application of high oscillatory frequencies requires the combination of HFOV with arteriovenous extracorporeal lung assist (av-ECLA) in order to maintain or reestablish normocapnia. Methods After induction of ARDS in eight female pigs (56.5 ± 4.4 kg), a recruitment manoeuvre was performed and intratracheal mean airway pressure (mPaw) was adjusted 3 cmH2O above the lower inflection point (Plow) of the pressure-volume curve. All animals were ventilated with oscillatory frequencies ranging from 3–15 Hz. The pressure amplitude was fixed at 60 cmH2O. At each frequency gas exchange and hemodynamic measurements were obtained with a clamped and de-clamped av-ECLA. Whenever the av-ECLA was de-clamped, the oxygen sweep gas flow through the membrane lung was adjusted aiming at normocapnia. Results Lung recruitment and adjustment of the mPaw above Plow resulted in a significant improvement of oxygenation (p < 0.05). Compared to lung injury, oxygenation remained significantly improved with rising frequencies (p < 0.05). Normocapnia during HFOV was only maintained with the addition of av-ECLA during frequencies of 9 Hz and above. Conclusion In this animal model of ARDS, maximization of oscillatory frequencies with subsequent minimization of VT leads to hypercapnia that can only be reversed by adding av-ECLA. When combined with a recruitment strategy, these high frequencies do not impair oxygenation PMID:19014575

  7. Assessment of high resolution digital elevation model for deep humus-rich sediments delineation at a plot scale

    NASA Astrophysics Data System (ADS)

    Penížek, Vít; Zádorová, Tereza

    2014-05-01

    Resolution and quality of digital elevation models is a key factor in erosion modeling. Spatial estimates of erosion and sedimentation rates are important for soil organic carbon stocks prediction or delineation of newly formed soil cover by degradation and sedimentation of soil material. Such analysis can be sensitive to DEM vertical accuracy and horizontal resolution. LIDAR data can provide very precise DEMs with very high resolution. In our study we used ground based LIDAR data with 10cm pixel. At such resolution, not only naturally formed terrain features are observed, but also anthropogenic features are depicted. Anthropogenic features are represented by more significant objects like hedges or ditches that can significantly influence the water and sediment movement in the landscape on one hand, on the other hand less significant anthropogenic impact can influence the terrain surface. Plot management forms a regular network consisting of parallel linear features given by plowing operations. At our research plot, such features depicted by DEM form specific flow direction (drainage) pattern over the area comparing to coarser resolution DEMs. We focused on comparison of differently preprocessed DEMs for deep humus-rich sediments depth prediction. We compared success rate of prediction models based on original DEM, DEMs with different resampling (resolution) and modeling of original DEM adding random noise given by size of plowing based terrain pattern. The study showed that original high resolution DEM significantly decreases the possibility of soil depth prediction. The actual very precise surface description is not very relevant for GIS modeling due to sensitivity of the models. DEMs depicting the wider constellations of the terrain were more successful in the prediction. The study was supported by grant nr. 13-07516P of the Czech science foundation and by grant nr. QJ1230319 of the Ministry of Agriculture.

  8. Contribution of macroporosity to infiltration into a continuous corn no-tilled watershed: Implications for contaminant movement

    NASA Astrophysics Data System (ADS)

    Edwards, W. M.; Shipitalo, M. J.; Norton, L. D.

    1988-12-01

    Rainfall and runoff were measured for many years on small watersheds on 10-15% slopes in east-central Ohio. Surface runoff from watersheds used for corn ( Zea mays L.) production was high with conventional tillage and very low with no-tillage. A 50-year storm produced 15 times more runoff from a plowed watershed than from a mulch-covered no-till watershed. Reduced runoff from the no-till surface resulted in increased percolation and enhanced the potential for transport of agricultural chemicals to the groundwater. The mulched surface of the no-till watershed also created a favorable environment for the deep burrowing earthworm, Lumbricus terrestris L., whose burrows can transmit water rapidly downward through the soil profile, thus contributing to the high infiltration rates. Open biopores and smaller structural pores were counted and measured to characterize the major flow paths of water movement in the no-till soil. Photos of horizontal surfaces at 2.5-, 7.5-, 15-, and 30 - cm depths and vertical faces of impregnated samples from the 1- and 5-cm depths were evaluated by image analysis. Number of pores was inversely proportional to pore diameter, however pores in the 0.05-1.0-mm diameter range accounted for less porosity than did those in the 1.0-5.0-mm range. The large pores were nearly vertical earthworm burrows and were continuously open from near the surface to the bedrock. Surface applications of lime increased subsoil pH in the no-till watershed but had little effect below the plow sole in the tilled watershed, suggesting that rapid movement of water in large pores can enhance chemical migration into the subsoil.

  9. Sediment losses and gains across a gradient of livestock grazing and plant invasion in a cool, semi-arid grassland, Colorado Plateau, USA

    NASA Astrophysics Data System (ADS)

    Belnap, Jayne; Reynolds, Richard L.; Reheis, Marith C.; Phillips, Susan L.; Urban, Frank E.; Goldstein, Harland L.

    Large sediment fluxes can have significant impacts on ecosystems. We measured incoming and outgoing sediment across a gradient of soil disturbance (livestock grazing, plowing) and annual plant invasion for 9 years. Our sites included two currently ungrazed sites: one never grazed by livestock and dominated by perennial grasses/well-developed biocrusts and one not grazed since 1974 and dominated by annual weeds with little biocrusts. We used two currently grazed sites: one dominated by annual weeds and the other dominated by perennial plants, both with little biocrusts. Precipitation was highly variable, with years of average, above-average, and extremely low precipitation. During years with average and above-average precipitation, the disturbed sites consistently produced 2.8 times more sediment than the currently undisturbed sites. The never grazed site always produced the least sediment of all the sites. During the drought years, we observed a 5600-fold increase in sediment production from the most disturbed site (dominated by annual grasses, plowed about 50 years previously and currently grazed by livestock) relative to the never grazed site dominated by perennial grasses and well-developed biocrusts, indicating a non-linear, synergistic response to increasing disturbance types and levels. Comparing sediment losses among the sites, biocrusts were most important in predicting site stability, followed by perennial plant cover. Incoming sediment was similar among the sites, and while inputs were up to 9-fold higher at the most heavily disturbed site during drought years compared to average years, the change during the drought conditions was small relative to the large change seen in the sediment outputs.

  10. Fabrication of Conductive Paths on a Fused Deposition Modeling Substrate using Inkjet Deposition

    DOE PAGESBeta

    Zhou, Wenchao; List, III, Frederick Alyious; Duty, Chad E.; Babu, Sudarsanam Suresh

    2015-01-15

    Inkjet deposition is one of the most attractive fabrication techniques for producing cost efficient and lightweight electronic devices on various substrates with low environmental impact. Fused Deposition Modeling (FDM) is one of the most used and reliable additive manufacturing processes by extrusion of wire-shaped thermoplastic materials, which provides an opportunity for embedding printed electronics into mechanical structures during the building process and enables the design of compact smart structures that can sense and adapt to their own state and the environment. This paper represents one of the first explorations of integrating inkjet deposition of silver nanoparticle inks with the FDMmore » process for making compact electro-mechanical structures. Three challenges have been identified and investigated, including the discontinuity of the printed lines resulting from the irregular surface of the FDM substrate, the non-conductivity of the printed lines due to the particle segregation during the droplet drying process, and the slow drying process caused by the skinning effect . Two different techniques are developed in this paper to address the issue of continuity of the printed lines, including surface ironing and a novel thermal plow technique that plows a channel in the FDM substrate to seal off the pores in the substrate and contain the deposited inks. Two solutions are also found for obtaining conductivity from the continuous printed lines, including porous surface coating and using a more viscous ink with larger nanoparticle size. Then the effects of the printing and post-processing parameters on the conductivity are examined. It is found that post-processing is a dominant factor in determining the conductivity of the printed lines.« less

  11. Application of radar to detect pedestrian workers near mining equipment.

    PubMed

    Ruff, T M

    2001-08-01

    Between 1990 and 1996, 133 accidents occurred and 23 mine workers were killed when haulage trucks used in surface mines collided with another smaller vehicle, a mine structure, or a pedestrian worker. These accidents were caused by a lack of visibility from the cab of the truck. Similar accidents are common with other types of equipment, such as front-end loaders and shovels. There are several methods for improving the operator's awareness of objects or people around the equipment including improved mirror designs, video cameras, and sensor technologies. Researchers at the National Institute for Occupational Safety and Health (NIOSH) are evaluating collision warning systems that are based on radar technology. These systems are mounted on the mining equipment to monitor one or more of the blind areas. An alarm is provided to the operator if an object or person enters the radar's detection area. Tests consisted of mounting the systems on a 50-ton-capacity truck typically used in quarries and a 240-ton-capacity truck used at a surface mine. This article summarizes the test procedure and results of evaluations of several off-the-shelf and prototype radar systems. False alarm rates and reliable detection zones for pedestrians were recorded for various mounting configurations on the rear of the trucks. Mounting radar systems on large equipment presents several challenges; however, the technology does show promise for this application. PMID:11504357

  12. Scanning electron microscopic structure of the lingual papillae of the common opossum (Didelphis marsupialis).

    PubMed

    Okada, Shigenori; Schraufnagel, Dean E

    2005-08-01

    The mammalian tongue has evolved for specialized functions in different species. The structure of its papillae tells about the animal's diet, habit, and taxonomy. The opossum has four kinds of lingual papillae (filiform, conical, fungiform, vallate). Scanning electron microscopy of the external features, connective tissue cores, and corrosion casts of the microvasculature show the filiform papillae have a spearhead-like main process and spiny accessory processes around the apical part of the main process. The shape and number of both processes depend on their position on the tongue. On the apex, the main processes have shovel-like capillary networks and the accessory processes have small conical networks. On the lingual radix, the processes have small capillary loops. In the patch region, conical papillae have capillaries arranged as a full sail curving posteriorly. The fungiform papillae are scattered among the filiform papillae and have capillary baskets beneath each taste bud. Giant fungiform papillae on the tongue tip are three to four times larger than the ones on the lingual body. Capillaries of giant papillae form a fan-shaped network. The opossum has three vallate papillae arranged in a triangle. Their tops have secondary capillary loops but not their lateral surfaces. Mucosal folds on the posterolateral border have irregular, fingerlike projections with cylindrical capillary networks. These findings and the structure of the rest of the masticatory apparatus suggest the lingual papillae of opossum have kept their ancestral carnivorous features but also developed the herbivore characteristics of other marsupials. PMID:16079016

  13. Prevalence and diversity of low pathogenicity avian influenza viruses in wild birds in Guatemala, 2010-2013

    PubMed Central

    Gonzalez-Reiche, Ana S.; Müller, Maria L.; Ortiz, Lucía; Cordón-Rosales, Celia; Perez, Daniel R.

    2016-01-01

    Summary Waterfowl species are known to harbor the greatest diversity of low pathogenicity influenza A virus (LPAIV) subtypes and are recognized as their main natural reservoir. In Guatemala there is evidence of circulation of LPAIV in wild ducks, however the bird species contributing to viral diversity during the winter migration in Central America are unknown. In this study, samples obtained from 1,250 hunter-killed birds from 22 different species were collected on the Pacific coast of Guatemala during three winter migration seasons between 2010 and 2013. Prevalence of LPAIV detected by real-time reverse-transcriptase polymerase chain reaction was 38.2%, 23.5% and 24.7% in the 2010-11, 2011-12, and 2012-13 seasons respectively. The highest virus prevalence was detected in the northern shoveler (Anas clypeata), followed by the blue-winged teal (Anas discors). The majority of positive samples and viral isolates were obtained from the blue-winged teal. Analysis of LPAIV prevalence over time in this species indicated a decreasing trend in monthly prevalence within a migration season. Sixty-eight viruses were isolated and 9 HA and 7 NA subtypes were identified in 19 subtype combinations. In 2012-13, the most prevalent subtype was H14, a subtype identified for the first time in the western hemisphere in 2010. The results from this study represent the most detailed description available to date of LPAIV circulation in Central America. PMID:27309080

  14. Anatomical and scanning electron microscopic investigations of the tongue and laryngeal entrance in the long-legged buzzard (Buteo rufinus, Cretzschmar, 1829).

    PubMed

    Erdoǧan, Serkan; Pèrez, William; Alan, Aydin

    2012-09-01

    This research aimed to examine the morphological features of the tongue and laryngeal entrance of long-legged buzzard by macroscopic and scanning electron microscopic methods. Two adult buzzards were used as material. The tongue was fairly elongated and terminated in oval shovel-like apex. Scale-like projections were localized on the apex and body of tongue. Both lateral sides of lingual body were contained considerably long thread-like projections. Many orifices of lingual posterior salivary glands were discerned among scale-like projections in median sulcus of the lingual body. Papillary crest of sharp conical papilla were observed on the between the body and root of the tongue. No conical papillae or other projections were existent on the root of the tongue, but numerous orifices of posterior salivary gland ducts were detected. In addition, orifices of anterior salivary gland ducts were present on the dorsal and lateral surfaces of the lingual body. Numerous conical papillae were observed on the caudal region of glottis and no conical papillae or any similar projection which were bordered the glottic fissure was noted. Anatomy of these organs in the long-legged buzzard and white tailed eagle which are the member of the same family, Accipitridae, revealed very high similarity. PMID:22496047

  15. Harpoon-based sample Acquisition System

    NASA Astrophysics Data System (ADS)

    Bernal, Javier; Nuth, Joseph; Wegel, Donald

    2012-02-01

    Acquiring information about the composition of comets, asteroids, and other near Earth objects is very important because they may contain the primordial ooze of the solar system and the origins of life on Earth. Sending a spacecraft is the obvious answer, but once it gets there it needs to collect and analyze samples. Conceptually, a drill or a shovel would work, but both require something extra to anchor it to the comet, adding to the cost and complexity of the spacecraft. Since comets and asteroids are very low gravity objects, drilling becomes a problem. If you do not provide a grappling mechanism, the drill would push the spacecraft off the surface. Harpoons have been proposed as grappling mechanisms in the past and are currently flying on missions such as ROSETTA. We propose to use a hollow, core sampling harpoon, to act as the anchoring mechanism as well as the sample collecting device. By combining these two functions, mass is reduced, more samples can be collected and the spacecraft can carry more propellant. Although challenging, returning the collected samples to Earth allows them to be analyzed in laboratories with much greater detail than possible on a spacecraft. Also, bringing the samples back to Earth allows future generations to study them.

  16. Locomotor benefits of being a slender and slick sand swimmer.

    PubMed

    Sharpe, Sarah S; Koehler, Stephan A; Kuckuk, Robyn M; Serrano, Miguel; Vela, Patricio A; Mendelson, Joseph; Goldman, Daniel I

    2015-02-01

    Squamates classified as 'subarenaceous' possess the ability to move long distances within dry sand; body elongation among sand and soil burrowers has been hypothesized to enhance subsurface performance. Using X-ray imaging, we performed the first kinematic investigation of the subsurface locomotion of the long, slender shovel-nosed snake (Chionactis occipitalis) and compared its biomechanics with those of the shorter, limbed sandfish lizard (Scincus scincus). The sandfish was previously shown to maximize swimming speed and minimize the mechanical cost of transport during burial. Our measurements revealed that the snake also swims through sand by propagating traveling waves down the body, head to tail. Unlike the sandfish, the snake nearly followed its own tracks, thus swimming in an approximate tube of self-fluidized granular media. We measured deviations from tube movement by introducing a parameter, the local slip angle, βs, which measures the angle between the direction of movement of each segment and body orientation. The average βs was smaller for the snake than for the sandfish; granular resistive force theory (RFT) revealed that the curvature utilized by each animal optimized its performance. The snake benefits from its slender body shape (and increased vertebral number), which allows propagation of a higher number of optimal curvature body undulations. The snake's low skin friction also increases performance. The agreement between experiment and RFT combined with the relatively simple properties of the granular 'frictional fluid' make subarenaceous swimming an attractive system to study functional morphology and bauplan evolution. PMID:25524983

  17. Australian open cut coal mine blasting practices and trends

    SciTech Connect

    Sengstock, G.W.; Kennedy, B.J.

    1995-12-31

    During the last two decades, many advances have been made in open cut coal mining technology as new mines have come on stream and old mines have faced increasingly difficult mining and operational conditions. The need for close control of operating costs has necessitated consideration of modified excavation methods. Mining systems now often include: truck/shovel prestripping ahead of dragline operations; dragline high walls of 50 meters; total pit depths in excess of 80 meters; mining of multiple coal seams, thin seams and thin partings; more focus on (and measurement of) excavation equipment productivity; and/or conformance to strict environmental limitations. To meet these challenging requirements, innovative explosive products, initiating explosives and delivery systems have been developed. Suitable blasting techniques such as throw blasting also assist coal mining operations to maintain competitiveness in a tough economic environment. This paper examines some of the changes in blasting practices in both open pit and strip mines throughout the Australian coal industry and considers some of the trends for the future.

  18. INTEGRATED ROBOT-HUMAN CONTROL IN MINING OPERATIONS

    SciTech Connect

    George Danko

    2006-04-01

    This report describes the results of the 2nd year of a research project on the implementation of a novel human-robot control system for hydraulic machinery. Sensor and valve re-calibration experiments were conducted to improve open loop machine control. A Cartesian control example was tested both in simulation and on the machine; the results are discussed in detail. The machine tests included open-loop as well as closed-loop motion control. Both methods worked reasonably well, due to the high-quality electro-hydraulic valves used on the experimental machine. Experiments on 3-D analysis of the bucket trajectory using marker tracking software are also presented with the results obtained. Open-loop control is robustly stable and free of short-term dynamic problems, but it allows for drifting away from the desired motion kinematics of the machine. A novel, closed-loop control adjustment provides a remedy, while retaining much of the advantages of the open-loop control based on kinematics transformation. Additional analysis of previously recorded, three-dimensional working trajectories of the bucket of large mine shovels was completed. The motion patterns, when transformed into a family of curves, serve as the basis for software-controlled machine kinematics transformation in the new human-robot control system.

  19. Recovery of Depleted Uranium Fragments from Soil

    SciTech Connect

    Farr, C.P.; Alecksen, T.J.; Heronimus, R.S.; Simonds, M.H.; Farrar, D.R.; Baker, K.R.; Miller, M.L.

    2008-07-01

    A cost-effective method was demonstrated for recovering depleted uranium (DU) fragments from soil. A compacted clean soil pad was prepared adjacent to a pile of soil containing DU fragments. Soil from the contaminated pile was placed on the pad in three-inch lifts using conventional construction equipment. Each lift was scanned with an automatic scanning system consisting of an array of radiation detectors coupled to a detector positioning system. The data were downloaded into ArcGIS for data presentation. Areas of the pad exhibiting scaler counts above the decision level were identified as likely locations of DU fragments. The coordinates of these locations were downloaded into a PDA that was wirelessly connected to the positioning system. The PDA guided technicians to the locations where hand-held trowels and shovels were used to remove the fragments. After DU removal, the affected areas were re-scanned and the new data patched into the data base to replace the original data. This new data set along with soil sample results served as final status survey data. (authors)

  20. Remote sensing techniques in cultural resource management archaeology

    NASA Astrophysics Data System (ADS)

    Johnson, Jay K.; Haley, Bryan S.

    2003-04-01

    Cultural resource management archaeology in the United States concerns compliance with legislation set in place to protect archaeological resources from the impact of modern activities. Traditionally, surface collection, shovel testing, test excavation, and mechanical stripping are used in these projects. These methods are expensive, time consuming, and may poorly represent the features within archaeological sites. The use of remote sensing techniques in cultural resource management archaeology may provide an answer to these problems. Near-surface geophysical techniques, including magnetometry, resistivity, electromagnetics, and ground penetrating radar, have proven to be particularly successful at efficiently locating archaeological features. Research has also indicated airborne and satellite remote sensing may hold some promise in the future for large-scale archaeological survey, although this is difficult in many areas of the world where ground cover reflect archaeological features in an indirect manner. A cost simulation of a hypothetical data recovery project on a large complex site in Mississippi is presented to illustrate the potential advantages of remote sensing in a cultural resource management setting. The results indicate these techniques can save a substantial amount of time and money for these projects.