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1

Mikkelson sweep/spike chisel plow shovel  

SciTech Connect

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.

Not Available

1992-01-01

2

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

SciTech Connect

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.

Not Available

1992-12-31

3

Effects of moldboard plowing, chisel plowing and rotation crops on the Rhizoctonia disease of white potato  

Microsoft Academic Search

Two tillage practices, chisel plowing (30 cm) and deep moldboard plowing (22 cm), and five rotation crops (oats, lupine, buckwheat,\\u000a broccoli and peas) were studied for their effects on the soil population ofRhizoctonia solani AG-3 and on Rhizoctonia disease on potato. All rotation crops were harvested except buckwheat, which was treated as a green\\u000a manure crop. Chisel plowing significantly reduced

S. S. Leach; G. A. Porter; R. V. Rourke; W. M. Clapham

1993-01-01

4

Pegasus plow  

SciTech Connect

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.

Thacker, G.W.

1997-04-01

5

Underwater hydraulic shock shovel control system  

Microsoft Academic Search

The control system determines the effectiveness of an underwater hydraulic shock shovel. This paper begins by analyzing the\\u000a working principles of these shovels and explains the importance of their control systems. A new type of control system’s mathematical\\u000a model was built and analyzed according to those principles. Since the initial control system’s response time could not fulfill\\u000a the design requirements,

He-Ping Liu; A-ni Luo; Hai-Yan Xiao

2008-01-01

6

Plowing Cables Under the Sea  

Microsoft Academic Search

The principal cause of submarine telephone cable failures has been fishing activities on the continental shelf, particularly in the Western Atlantic area. The Bell System has conducted extensive investigation of methods of burying these cables in the affected area to eliminate this hazard. This has culminated in the development of a unique underwater plow which was used successfully in July

C. Duncan

1969-01-01

7

30 CFR 77.409 - Shovels, draglines, and tractors.  

...HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.409 Shovels, draglines, and tractors. (a) Shovels, draglines, and tractors shall not...

2014-07-01

8

Optimised dipper fine tunes shovel performance  

SciTech Connect

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.

Fiscor, S.

2005-06-01

9

Long-term foraging optimization in northern shovelers  

Microsoft Academic Search

In this paper I attempt to explain the seasonal foraging strategy employed by male northern shovelers (Anas clypeata). Through the use of dynamic-optimization modeling I demonstrate that male shovelers are optimizing total foraging time over the entire summer by foraging heavily when resources (cladocerans) are abundant and utilizing endogenous reserves during times when resources are in short supply. Additionally, I

Paul J. DuBowy

1997-01-01

10

OEM unveil new ideas for shovels and excavators  

SciTech Connect

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.

Fiscor, S.

2006-08-15

11

Electric shovels meet the demands for mining operations  

SciTech Connect

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.

Fiscor, S.

2008-03-15

12

INTERIOR VIEW, LOOKING SOUTHWEST, 395 BUCYRUS ERIE SHOVEL CLEANING OVERBURDEN ...  

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

INTERIOR VIEW, LOOKING SOUTHWEST, 395 BUCYRUS ERIE SHOVEL CLEANING OVERBURDEN FROM LEDGE TO ACCESS COAL SEAMS BELOW. - Drummond Coal Company Cedrum Mine, 8750 Pit, County Road 124, Townley, Walker County, AL

13

INTERIOR VIEW, LOOKING SOUTHEAST, 395 BUCYRUS ERIE SHOVEL CLEANING OVERBURDEN ...  

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

INTERIOR VIEW, LOOKING SOUTHEAST, 395 BUCYRUS ERIE SHOVEL CLEANING OVERBURDEN FROM LEDGE SO THAT DRAGLINE CAN CONTINUE REMOVING OVERBURDEN TO ACCESS LEVELS OF THE COAL SEAMS. - Drummond Coal Company Cedrum Mine, 8750 Pit, County Road 124, Townley, Walker County, AL

14

An atypical clay shoveler's fracture: a case report  

PubMed Central

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

Feldman, Victor B; Astri, Frank

2001-01-01

15

The Snow-Shoveler's ST Elevation Myocardial Infarction  

PubMed Central

Heavy snowfall, cold temperatures, and low atmospheric pressure during the winter months have been associated with increased adverse cardiovascular events. However, only a few cases of the “snow -shoveler’s infarction ” have been reported. We present our experience with 6 patients presenting with ST elevation myocardial infarction all within a 24-hour period during an unprecedented snowfall (4 of whom were shoveling snow), and provide a detailed review of previously reported cases of snow-shoveler’s infarction. Consistent with other reports, the majority of our patients had the traditional cardiac risk factors of hypertension, hyperlipidemia, diabetes mellitus, tobacco use, and were habitually sedentary. Unique to our case series, however, was that the four patients who had a history of coronary artery disease and prior coronary artery stenting, all presented with subacute stent thrombosis documented on the coronary angiography performed emergently. Moreover, these patients constituted 25% of all the subacute stent thromboses diagnosed in our cardiac catheterization laboratory over the preceding 12 months. In conclusion, our findings suggest that in typically sedentary individuals with cardiac risk factors or a history of coronary artery disease, snow shoveling may trigger ST elevation myocardial infarction and, therefore, should be avoided. This may be most critical in patients with a history of coronary stent placement since our findings suggest that snow shoveling may precipitate subacute stent thrombosis. PMID:20691323

Janardhanan, Rajesh; Henry, Zachary; Hur, David J.; Lin, Christine M.; Lopez, David; Reagan, Patrick M.; Rudnick, Sean R.; Koshko, Travis J.; Keeley, Ellen C.

2010-01-01

16

International Plowing Match & Farm Machinery Show  

NSDL National Science Digital Library

The 1995 International Plowing Match & Farm Machinery Show in Ontario, Canada has a site of the Web. The IPM is a non-profit organization of volunteers which annually organizes Canada's largest farm machinery show. The event is commercial and educational. Thousands of school children and educators attend and participate in organized educational activities.

1995-01-01

17

Shovel Operator. Open Pit Mining Job Training Series.  

ERIC Educational Resources Information Center

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…

Hartley, Larry

18

Rotylenchulus reniformis below Plow Depth Suppresses Cotton Yield and Root Growth.  

PubMed

Damage to cotton by Rotylenchulus reniformis below plow depth was evaluated in a sandy clay loam soil at Weslaco, Texas. In December 1999, 14 holes on 51-cm centers were dug 91 cm deep along the planting bed and adjacent furrow and 2 ml of 1,3-dichloropropene was placed 91, 61, and 30 cm deep as each hole was refilled and packed. This technique eliminated 96%, 81%, and 74% of R. reniformis down to 107 cm at distances 0, 25, and 51 cm laterally from the point of application (P chisel fumigation at 168 liters/ha 43 cm deep reduced nematode numbers only in the top 61 cm (P chisel fumigation increased yield 88% (P

Robinson, A F; Cook, C G; Westphal, A; Bradford, J M

2005-09-01

19

BIOENERGETICS OF BREEDING NORTHERN SHOVELERS: DIET, NUTRIENT RESERVES, CLUTCH SIZE, AND INCUBATION  

Microsoft Academic Search

We analyzed food habits, digestive organs, and nutrient reserves (lipid, protein, and mineral) of male and female Northern Shovelers (Anas clypeata) nesting in southern Manitoba. We studied shovelers because, on an annual basis, they consume more animal matter than do other Anas spp. Thus, they are ideal subjects for testing the hypothesis that the inability of female ducks to obtain

C. DAVISON ANKNEY; ALAN D. AFTON

1988-01-01

20

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

SciTech Connect

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.

Lukach, J.

1992-06-19

21

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

SciTech Connect

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.

Lukach, J.

1992-06-19

22

Seasonal variations of steroid hormones and triiodothyronine concentrations in migratory northern shovelers.  

PubMed

Endogenous serum testosterone, estradiol, and triiodothyronine concentrations were measured in the northern shoveler (Anas clypeata, n = 20) during different stages of migratory condition at their wintering grounds to look at how these hormones may be linked to the development of migratory condition. These hormones were assayed by enzyme-linked immunosorbent assay (ELISA). The changes in hormones concentrations were parallel to each other and correspond to the increasing day lengths of spring. Furthermore, the northern shovelers showed a distinct seasonal cycle in serum concentrations of triiodothyronine, estradiol, and testosterone. It is suggested that these seasonal cycles in the northern shovelers are endogenously programmed and their entrainment to the environmental photoperiod ensures the occurrence of different physiological functions at temporally fixed time of the year. The results of this study offer a captive model of the seasonal changes in physiology and behavior that occur in the months preceding and including vernal migration of the northern shovelers. PMID:22331661

Elarabany, N F; Abdallah, G A; Said, A E

2012-04-01

23

Post-trenching plow cuts ditch under offshore line  

SciTech Connect

In a 15-day operation, a 68-ton, 60-ft-long underwater post-trenching plow successfully cut an approximately 4-ft-deep protective trench under the 23-mile-long, 24-in.-diameter gas-transmission pipeline connecting Esso Australia's Snapper A platform to shore in Australia's Bass Strait. Scale-model tests had provided towing-force data and proved the feasibility of split, butterfly-type shares that wrap around the pipe. A yoke on the pull-cable attachment, which places the pulling points on the shares rather than on the plow body, permitted the use of a much lighter body, thus saving about 30 tons of steel. Underwater television cameras monitored the plow's instrumentation panel, which received data on horizontal and vertical loads, the position of the shares, cutting depth and forward speed, and pull-cable horizontal and vertical departure angles from the plow. The soils encountered along the line included high-water-content quicksand, firm sand, cemented sandstone, and hard limestone.

Brown, R.J.

1980-06-01

24

Ingestion of lead and nontoxic shot by Green-winged Teal (Anas crecca) and Northern Shovelers (Anas clypeata) from the mid-Gulf Coast of Texas, USA.  

PubMed

Ninety-eight Green-winged Teal (Anas crecca) and 84 Northern Shoveler (Anas clypeata) gizzards were examined for ingested shot. One Northern Shoveler had lead and three had steel shot; 24 teal and 17 shovelers had composite nontoxic shot or nonlead metal fragments. Prevalence of ingested lead appears minimal and consistent with other studies conducted after lead-shot bans. PMID:21719854

Garrison, Drew A; Fedynich, Alan M; Smith, Autumn J; Ferro, Pamela J; Butler, David A; Peterson, Markus J; Lupiani, Blanca

2011-07-01

25

PARASITES OF WATERFOWL FROM SOUTHWEST TEXAS: II. THE SHOVELER, Anas clypeata  

Microsoft Academic Search

Thirty-eight shoveler ducks, Anas clypeata, were collected in the Rio Grande Valley, Hudspeth County, Texas. Nineteen species of helminths, six species of lice and a sarcosporidian, Sancocystis nileyi, were recorded. Seventeen of the nine- teen species of helminths were observed in fall migrants and twelve species were recorded from spring migrants. The nematode A\\/if ilania pochandi Au, 1969, is a

DOROTHY BRODERSON; ALBERT G. CANARIS; JOHN R. BRISTOL

26

Distribution and status of wintering Shovelers Anas clypeata in Great Britain  

Microsoft Academic Search

The distribution and status of Shovelers using British wetlands in autumn and winter was examined using ringing recoveries and National Waterfowl Count data. Maximum counts have been around 8500 and suggest a total population of c. 10 000. Some of these birds originate from north-west continental Europe, eastern Scandinavia and the Western former USSR, whilst others originate from British breeding

J. S. Kirkby; C. Mitchell

1993-01-01

27

Snow blowing and shoveling in normal and asymptomatic coronary artery diseased men.  

PubMed

We evaluated the oxygen uptake and heart-rate responses to self-paced snow blowing and snow shoveling in 10 men with asymptomatic coronary artery disease, 10 older normal men, and six younger normal men. Mean peak treadmill oxygen uptake in the three groups ranged from 26.4 +/- 1.1 to 47.3 +/- 3.9 ml/kg per min (P < 0.05). Oxygen uptake during snow blowing did not differ significantly among subject groups; values were 17.1 +/- 1.3, 17.7 +/- 1.1, and 17.2 +/- 0.9 ml/kg per min in the coronary artery disease, older normal, and younger normal groups, respectively. Oxygen uptake with snow shoveling was lower (P < 0.05) in those with coronary artery disease (18.4 +/- 1.0 ml/kg per min) than in the normal groups. In comparison with snow shoveling, oxygen uptake and heart rate did not differ (P = NS) from snow blowing in the coronary artery disease group but were lower (P < 0.05) with snow blowing in the two normal groups. The results indicate that men with asymptomatic coronary artery disease and relatively good functional work capacity perform snow blowing and snow shoveling at similar levels of oxygen uptake and heart rate. PMID:7514155

Sheldahl, L M; Wilke, N A; Dougherty, S; Tristani, F E

1994-03-01

28

PARASITES OF WATERFOWL FROM SOUTHWEST TEXAS: II. THE SHOVELER, Anas clypeata.  

PubMed

Thirty-eight shoveler ducks, Anas clypeata , were collected in the Rio Grande Valley, Hudspeth County, Texas. Nineteen species of helminths, six species of lice and a sarcosporidian, Sarcocystis rileyi , were recorded. Seventeen of the nineteen species of helminths were observed in fall migrants and twelve species were recorded from spring migrants. The nematode Alifilaria pochardi Ali, 1969, is a new host and American record. PMID:24228969

Broderson, D; Canaris, A G; Bristol, J R

1977-10-01

29

Shovel roots: a unique stress-avoiding developmental strategy of the legume plant Hedysarum coronarium L  

Microsoft Academic Search

Hedysarum coronarium (sulla) is a legume native to the Mediterranean basin, known for its broad tolerance to various environmental stresses, and\\u000a its ability to thrive without signs of chlorosis when growing in arid and alkaline soils up to pH 9.6. A unique but poorly\\u000a known morphological feature of its root system is the production of “shovels”, modified lateral roots that

Elisabetta Tola; Josè Liberato Henriquez-Sabà; Elisa Polone; Frank B. Dazzo; Giuseppe Concheri; Sergio Casella; Andrea Squartini

2009-01-01

30

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

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

Mt Pleasant, Jane

2011-01-01

31

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

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.

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

2008-01-01

32

Specific draught for mouldboard plough, chisel plough and disc harrow at different water contents  

Microsoft Academic Search

The objective of the present study was to measure the specific draught (force per cross-sectional area of worked soil) and energy use for soil fragmentation for different tillage implements and soil conditions. Draught was calculated from measurements of fuel consumption and speed during tillage with a mouldboard plough and a chisel plough set to working depths of 13, 17 and

Johan Arvidsson; Thomas Keller; Karin Gustafsson

2004-01-01

33

The relation between the feeding activity of wintering shovelers (Anas clypeata) and the horizontal distribution of zooplankton in Lake Teganuma, Japan  

Microsoft Academic Search

We investigated seasonal changes in the number and feeding activity of Shovelers wintering in Lake Teganuma in connection with temporal and horizontal fluctuations of zooplankton, and analyzed esophageal contents of a captured Shoveler. Zooplankton community was dominated by rotifers followed by copepods during the study period. Horizontal distribution of both invertebrate taxa differed; rotifers most abundant in the western and

Takeshi Matsubara; Fumio Sugimori; Kiyoshi Iwabuchi; Kanji Aoyama

1994-01-01

34

EXPERIMENTAL TRANSMISSION OF Sarcocystis sp. (PROTOZOA: SARCOCYSTIDAE) BETWEEN THE SHOVELER (Anas clypeata) DUCK AND THE STRIPED SKUNK (Mephitis mephitis)  

Microsoft Academic Search

Muscle containing macroscopic cysts of Sarcocystis sp. from naturally infected wild shoveler (Anas clypeata) ducks was fed to two captive striped skunks (Mephitis mephitis). The skunks passed sporocysts in their feces beginning 19 and 22 days post-infection, and continued to pass small numbers of sporocysts sporadically to 63 and 51 days post-infection, respectively. Sporocysts from the skunks were administered orally

R. J. CAWTHORN; D. RAINNIE; G. WOBESER

35

Experimental transmission of Sarcocystis sp. (Protozoa: Sarcocystidae) between the shoveler (Anas clypeata) duck and the striped skunk (Mephitis mephitis).  

PubMed

Muscle containing macroscopic cysts of Sarcocystis sp. from naturally infected wild shoveler (Anas clypeata) ducks was fed to two captive striped skunks (Mephitis mephitis). The skunks passed sporocysts in their feces beginning 19 and 22 days post-infection, and continued to pass small numbers of sporocysts sporadically to 63 and 51 days post-infection, respectively. Sporocysts from the skunks were administered orally to four laboratory-reared shovelers. No cysts were found in ducks examined 56 and 84 days post-infection. One duck examined at 85 days post-infection had many microscopic cysts in its skeletal muscle. The remaining duck had numerous small macroscopic cysts in muscle at 154 days post-infection. A skunk fed muscle from this duck began to pass sporocysts on day 18 post-infection. All cysts in muscle (natural and experimental infection) had irregular cauliflower-like projections of the primary cyst wall. PMID:6796702

Cawthorn, R J; Rainnie, D; Wobeser, G

1981-07-01

36

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

USGS Publications Warehouse

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.

Miller, M. R.

1984-01-01

37

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

SciTech Connect

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.

Thacker, G.W.

1995-10-23

38

Microsatellite genotyping of red imported fire ant (Hymenoptera: Formicidae) colonies reveals that most colonies persist in plowed pastures.  

PubMed

Our study focused on colony dynamics of the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), in relation to the standard practice of planting rye grass (i.e., plowing) in the fall in Louisiana. Microsatellite molecular markers were used to determine genotypes of individuals from red imported fire ant colonies. These markers allowed us to monitor treatment effect by detecting changes in number and location of colonies in response to disking of pasture plots. Previous research on mound disturbance as a form of cultural control in pastures has produced mixed results. We found that the majority of colonies persisted on plots after plowing. Mound density and mound area, 5 mo after plowing, were not significantly different among treatments. In contrast, April measurements of mound volume were significantly smaller on plowed plots compared with control plots. A closer look at the rebuilding of mounds on plowed plots, during the 5 mo, showed that mound heights stayed below pretreatment measurements and they were significantly smaller than those of undisturbed mounds. Whether plowing has potential for use as a cultural control technique in reducing the impact of red imported fire ant mounds on agricultural practices in pastures remains to be seen. Conceivably, the best application of this technique will be in combination with other control measures in an integrated pest management approach to control red imported fire ants in pastures. PMID:18767710

Colby, D; Husseneder, C; Foil, L

2008-08-01

39

Ground Beetle (Coleoptera: Carabidae) Assemblages in Organic, No-Till, and Chisel-Till Cropping Systems in Maryland  

Microsoft Academic Search

Ground beetle assemblages were compared in organic, no-till, and chisel-till cropping systems of the USDA Farming Systems Project in Maryland. The cropping systems consisted of 3-yr rotations of corn (Zea mays L.), soybean (Glycine max L. Merr.), and wheat (Triticum aestivum L.) that were planted to corn and soybean during the 2 yr of Þeld sampling (2001Ð2002). Each year, ground

Sean Clark; Katalin Szlavecz; Michel A. Cavigelli; Foster Purrington

2006-01-01

40

Properties of agricultural aerosol released during wheat harvest threshing, plowing and sowing.  

PubMed

This study shows for the first time a chemical and morphological characterization of agricultural aerosols released during three important agricultural operations: threshing, plowing and sowing. The field campaigns were carried out in the eastern part of the Po Valley, Italy, in summer and autumn 2009. The aerosol particles were sampled on quartz fiber filters and polytetrafluoroethylene membranes in order to allow Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis and Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDS) investigations, respectively. The organic carbon mass concentrations were measured with a Sunset Laboratory Dual-Optical Organic Carbone/Elemental Carbon (OCEC) Aerosol analyzer. The morphological and chemical analyses by SEM-EDS allowed recognizing four main particle classes: organic, silica, calcite and clay minerals. The organic particles contribute to both fine and coarse aerosol fractions up to ca. 50% for all three agricultural activities. This was also confirmed by OCEC analysis for fine fraction. Most of the agricultural aerosols, about 60%, were single particles and the remaining 40% were agglomerations of particles. The ICP-MS results showed that threshing and plowing produce more aerosol particles than sowing, which was characterized by important amounts of clay minerals produced from land soils. PMID:25193841

Telloli, Chiara; Malaguti, Antonella; Mircea, Mihaela; Tassinari, Renzo; Vaccaro, Carmela; Berico, Massimo

2014-09-01

41

Lift and drag forces on an inclined plow moving over a granular surface  

E-print Network

We studied the drag and lift forces acting on an inclined plate while it is dragged on the surface of a granular media, both in experiment and numerical simulation. In particular, we investigated the influence of the horizontal velocity of the plate and its angle of attack. We show that a steady wedge of grains is moved in front of the plow and that the lift and drag forces are proportional to the weight of this wedge. These constants of proportionality vary with the angle of attack but not (or only weakly) on the velocity. We found a universal effective friction law which accounts for the dependence on all the above-mentioned parameters. The stress and velocity fields are calculated from the numerical simulations and show the existence of a shear band under the wedge and that the pressure is non-hydrostatic. The strongest gradients in stress and shear occur at the base of the plow where the dissipation rate is therefore highest.

Baptiste Percier; Sebastien Manneville; Jim N. McElwaine; Stephen Morris; Nicolas Taberlet

2011-07-27

42

Continuous dental replacement in a hyper-chisel tooth digging rodent  

PubMed Central

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

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

2011-01-01

43

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

SciTech Connect

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 ?m in length with 300 nm spacing between lines) can be fabricated at a high speed of ?5 mm/s, with the line width and the line depth at ?95 nm and 2 nm, respectively. A fine pattern of the word “NANO” is also fabricated at the speed of ?5 mm/s.

Wang, Zhihua; Zou, Qingze, E-mail: qzzou@rci.rutgers.edu [Mechanical and Aerospace Engineering Department, Rutgers, the State University of New Jersey, Piscataway, New Jersey 08854 (United States)] [Mechanical and Aerospace Engineering Department, Rutgers, the State University of New Jersey, Piscataway, New Jersey 08854 (United States); Tan, Jun; Jiang, Wei [Electrical and Computer Engineering Department, Rutgers, the State University of New Jersey, Piscataway, New Jersey 08854 (United States)] [Electrical and Computer Engineering Department, Rutgers, the State University of New Jersey, Piscataway, New Jersey 08854 (United States)

2013-11-15

44

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

NASA Astrophysics Data System (ADS)

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 ?m in length with 300 nm spacing between lines) can be fabricated at a high speed of ˜5 mm/s, with the line width and the line depth at ˜95 nm and 2 nm, respectively. A fine pattern of the word "NANO" is also fabricated at the speed of ˜5 mm/s.

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

2013-11-01

45

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

PubMed

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 ?m in length with 300 nm spacing between lines) can be fabricated at a high speed of ~5 mm/s, with the line width and the line depth at ~95 nm and 2 nm, respectively. A fine pattern of the word "NANO" is also fabricated at the speed of ~5 mm/s. PMID:24289401

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

2013-11-01

46

Estimating Sliding Velocity of a Pleistocene Ice Sheet From Plowing Structures in the Geologic Record  

NASA Astrophysics Data System (ADS)

As an ice sheet slides over a sediment bed, some clasts partly embedded in the glacier sole plow through the bed surface. The size distribution of such clasts, if it can be characterized from structures in the geologic record, can be used to estimate the sliding velocity of a past ice sheet. By combining a theory of glacier sliding with a geotechnical theory of cone penetration, sliding velocity can be calculated in terms of clast-size parameters, a fluidity parameter for ice, and the thermodynamic properties of ice and clasts. If frictional properties of the bed are measured, the effective normal stress on the bed and bed shear strength during glaciation can also be calculated. We used this approach to estimate the sliding velocity of an Illinoian ice sheet that left plowing structures in cemented outwash near Peoria, Illinois. Fluidity parameters for normal and basal temperate ice yielded sliding velocities of 140-168 m/yr and 60-72 m/yr, respectively. These are overestimates if solutes impeded regelation of ice past clasts or if friction between debris-laden ice and clasts retarded slip. Preconsolidation stresses determined in laboratory tests on silt from the bed agree with effective normal stresses calculated using clast-size parameters. The high shear strength of the bed (>145 kPa) and primary structures preserved within it indicate that additional movement due to pervasive shear of the bed was unlikely. Application of this method elsewhere where basal tills overly outwash would provide basal-velocity data that are otherwise unavailable for testing and tuning of ice-sheet models; we know of no other method for estimating sliding velocity from glacial sediments.

Iverson, N. R.; Hooyer, T. S.

2004-05-01

47

Estimating the sliding velocity of a Pleistocene ice sheet from plowing structures in the geologic record  

NASA Astrophysics Data System (ADS)

As an ice sheet slides over its sediment bed, some clasts partly embedded in the glacier sole plow through the bed surface. The size distribution of such clasts, if it can be characterized from structures in the geologic record, can be used to estimate the sliding velocity of a past ice sheet. By combining a theory of glacier sliding with a geotechnical theory of cone penetration, sliding velocity can be calculated in terms of clast-size parameters, a fluidity parameter for ice, and the thermodynamic properties of ice and clasts. If frictional properties of the bed are measured, the effective normal stress on the bed and bed shear strength during glaciation can also be calculated. We used this approach to estimate the sliding velocity of an Illinoian ice sheet that left plowing structures in cemented outwash near Peoria, Illinois. Fluidity parameters for normal and basal temperate ice yielded sliding velocities of 140-168 m yr-1 and 60-72 m yr-1, respectively. These are overestimates if solutes impeded regelation of ice past clasts or if friction between debris-laden ice and clasts retarded slip. Preconsolidation stresses determined in laboratory tests on silt from the bed agree with effective normal stresses calculated using clast-size parameters. The high shear strength of the bed (>145 kPa) and primary structures preserved within it indicate that additional movement due to pervasive shear of the bed was unlikely. Application of this method elsewhere would provide basal velocity data that are otherwise unavailable for testing and tuning of ice sheet models.

Iverson, Neal R.; Hooyer, Thomas S.

2004-12-01

48

Shoveling Snow I n f o r m a t i o n f r o m Ve r m o n t  

E-print Network

-656-5420 or 1-800-571-0668, Fax:802-656-5422 Snow shoveling is one of the most high-intensity exercises you can Anyone with a history of heart disease. Anyone with high blood pressure or high cholesterol levels the snow rather than lift it. Save your back and your energy by simply pushing the snow to the side. If you

Hayden, Nancy J.

49

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

PubMed Central

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

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

2014-01-01

50

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

USGS Publications Warehouse

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.

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

2014-01-01

51

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

USGS Publications Warehouse

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.

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

2013-01-01

52

DIVISION S-6—SOIL & WATER MANAGEMENT & CONSERVATION Tillage and Crop Influences on Physical Properties for an Epiaqualf  

Microsoft Academic Search

tillage usually has been found to increase b compared with moldboard and chisel plow (Kitur et al., 1993; Lal, Tillage impacts on soil properties differ among soils. This study 1999). Bulk density usually is lowest immediately after investigated tillage, cropping, and wheel traffic (WT) effects of 13-yr of no-tillage (NT), chisel plow (CP), and moldboard plow (MP) under tillage and

Humberto Blanco-Canqui; C. J. Gantzer; S. H. Anderson; E. E. Alberts

53

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

SciTech Connect

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.

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

2006-09-01

54

Spatial variability and temporal changes in the heavy metal content of soils with a deep furrow-and-ridge microrelief formed by an afforestation plowing.  

PubMed

An appropriate sampling method that provides for the representation of the collected material and the reliability of results plays a crucial role in environmental monitoring. This is especially important in soil quality investigations on sites with a differentiated surface microrelief, as in the case of afforested post-arable soils that have a specific, deep furrow-and-ridge microrelief. The present research was carried out on three sites afforested with pine (4-, 8-, and 15-year-old stands) located near a large tailings pond collecting the wastes from copper ore enrichment. Soils were sampled at depths of 0-10 and 0-30 cm, separately in the furrows and ridges. The "wide-furrow plow" contributed to the spatial variation in soil properties, including higher pH, organic carbon, and Cu content in soils of the ridges. The difference in Cu content in the ridges and furrows initially reached 300 %, and decreased with the decline of the furrow-and-ridge microrelief to 60 % at 15 years after the plowing. Observed rate of the furrow shallowing allows for an estimation of the time necessary for the complete disappearance of the furrow-and-ridge microrelief and associated variability in soil properties to at least 30-40 years after the plowing. Afforestation plowing had little impact on the Zn variability which was not influenced by the emissions from the tailings pond. Soil sampling in contaminated sites with furrow-and-ridge microrelief must collect equal quantities of soil samples from both furrows and ridges to allow a reliable estimation of the mean trace elements' concentration. PMID:23079794

Kabala, Cezary; Bojko, Oskar; Medynska, Agnieszka; Szczepaniak, Agnieszka

2013-06-01

55

TILLAGE & MANURE TIMING TO MINIMIZE  

E-print Network

P losses · Tillage often increases sediment /particulate P in runoff. · Spreading manure on no-till ongoing. Datasets growing. #12;SPRING MANURE TREATMENTS · Tillage No-till Chisel plow · Manure (spring ----- % ----- ----- mm ----- No-till - 79 47 11 17 No-till + 99 74 1 5 C. Plow - 26 16 4 29 C. Plow + 50 23 1 14 #12

Balser, Teri C.

56

Agronomy Guide West Lafayette, Indiana 47907  

E-print Network

. Several tillage systems, including chisel plow, disk, ridge-till, and no-till systems, can leave 30 operations will generally leave about a 30 percent cover. In high yielding soybean residue, however, no-till

Holland, Jeffrey

57

CONSERVATION TILLAGE ISSUES FOR NW WISCONSIN  

E-print Network

INTENSITY EVERY FIELD DOES NOT HAVE TO BE PLOWED NO-TILL OR MINIMUM TILL INTO FALL KILLED ALFALFA EARTH WORMS % g/kg No./m2 No-till 46 24 78 Chisel 34 16 52 Plow 36 11 53 Karlen et al., 1994 #12;STRIP-May DEGREEC STRIP-TILL CHISEL NO-TILL 2 " DEPTH MEASURED 4:00-5:00 PM Effect on in-row soil

Balser, Teri C.

58

Influences of organic and synthetic soil fertility amendments on nematode trophic groups and community dynamics under tomatoes  

Microsoft Academic Search

Research was conducted to examine the effects of organic and synthetic soil amendments and tillage on nematode communities in field soils planted to tomato (Lycopersicon esculentum) at two locations. The experimental design was a replicated split plot with chisel-plow tillage and bare-soil or chisel-plow tillage and surface mulch with wheat straw as main plots, and soil amendments of synthetic fertilizer,

L. R. Bulluck; K. R. Barker; J. B. Ristaino

2002-01-01

59

Comparing Tillage Techniques by Using a New Infiltration Method  

Microsoft Academic Search

A one-year field trial in Italy was carried out for comparing tillage systems such as 50 cm chiselling (CH), 40 cm plow-till (PT40) and 20 cm plow-till (PT20) according to results of a new developed infiltration method. Ponded infiltration rates were measured to obtain the field saturated hydraulic conductivity (Kfs) using single ring infiltrometers on six dates with six replications

Fatih TOPALO

60

Soil compaction and root distribution for okra as affected by tillage and vehicle parameters  

Microsoft Academic Search

Many soil physical properties and crop yield are affected by compaction and tillage systems. The effect of three different factors, i.e. tillage treatments (no-tillage, chisel plowing, and moldboard plowing), axle load (6 and 16t\\/axle vehicle), and tire inflation pressure (120 and 350kPa inflation pressures) on okra (Abelmoschus esculentus) root density and soil physical properties (bulk density and cone penetration resistance)

Nidal H Abu-Hamdeh

2003-01-01

61

Effect of tillage and residue management on enzyme activities in soils: III. Phosphatases and arylsulfatase  

Microsoft Academic Search

This study was carried out to investigate the effect of tillage and residue management on activities of phosphatases (acid\\u000a phosphatase, alkaline phosphatase, phosphodiesterase, and inorganic pyrophosphatase) and arylsulfatase. The land treatments\\u000a included three tillage systems (no-till, chisel plow, and moldboard plow) in combination with corn residue placements in four\\u000a replications. The activities of these enzymes in no-till\\/double mulch were significantly

S. P. Deng; M. A. Tabatabai

1997-01-01

62

Degradation of isofenphos in cornfields with conservation tillage practices  

Microsoft Academic Search

Isofenphos (Amaze®, Oftanol®, 1?methylethyl 2?[[ethoxy?[(l?methylethyl)aminol phosphinothloyl]oxy]benzoate) was applied at planting to study the effects of four different tillage treatments (no?tillage, fall chisel plow, Paraplow®, and fall moldboard plow) on isofenphos degradation rates and routes in cornfields over two growing seasons. Soil samples were taken at intervals extending over 69 days each growing season. Tillage treatment had no significant effect on

J. R. Coats; M. E. Gray; J. J. Tollefson

1986-01-01

63

Weed seed bank affected by tillage intensity for barley in Alaska  

Microsoft Academic Search

The weed seed bank of a long-term tillage study in subarctic Alaska was studied at the end of 10 years of continuous spring barley (Hordeum vulgare L.). Tillage treatments were: no-till, disked once (spring), disked twice (spring and fall), and chisel plow (fall). Soil cores were obtained from each tillage treatment and seeds were manually separated from soil after washing

Jeffery S. Conn

2006-01-01

64

Soil Test Phosphorus Stratification Survey Sampling Protocol, Spring 2008  

E-print Network

to valid conclusions. If no-till or strip till is used in your area, include at least one sample of one, eroded) with four from chisel-plowed systems and two from no-till systems. Sampling: Sample as early

Balser, Teri C.

65

NO-TILL CORN TO POTASSIUM (K)  

E-print Network

NO-TILL CORN RESPONSE TO POTASSIUM (K) FERTILIZATION Larry Bundy and Todd Andraski #12;Introduction · Frequent reports of K deficiency. · More often seen in no-till. · Do current soil test K recommendations & chisel plowed) to expand the range of soil test levels. · No-till in 1994 and 1996. #12;Soil K response

Balser, Teri C.

66

Soil organic carbon, microbial biomass and CO 2-C production from three tillage systems  

Microsoft Academic Search

Organic matter is a major soil component which is influenced by tillage. This paper quantifies the effect of no-till, chisel tillage and plow tillage on the content and depth distribution of organic carbon and microbial biomass after 12 years of each tillage system. The soil was typical of the Argentine Rolling Pampa. The resistance of organic matter to mineralization was

Roberto Alvarez; Raúl A. Díaz; Nidia Barbero; Oscar J. Santanatoglia; Luis Blotta

1995-01-01

67

Land use and environmental factors influencing soil surface CO 2 flux and microbial biomass in natural and managed ecosystems in southern Wisconsin  

Microsoft Academic Search

Many of the native prairies in southern Wisconsin, and the midwestern United States in general, have been replaced by conventional till (chisel plow) and no-tillage corn agroecosystems. However, knowledge of the influence of land use change on the structure and function of ecosystems is incomplete. Soil surface CO2 flux is a major transfer of carbon from terrestrial ecosystems to the

Rota Wagai; Kristofor R. Brye; Stith T. Gower; John M. Norman; Larry G. Bundy

1998-01-01

68

CROP RESPONSE TO SOIL TEST P & K AND  

E-print Network

;#12;Introduction · Frequent reports of K deficiency. · More often seen in no-till. · Do current soil test K (1993 & 1995 ­ spring disked & chisel plowed) to expand the range of soil test levels. · No-till in 1994

Balser, Teri C.

69

Agronomy Notes Dec 2011 Volume 35:12  

E-print Network

it is turned or chisel plowed which destroys the stand. Most growers will want to use a no-till drill to plant in April. Wheat yield planted with a no-till drill behind soybean, bahia , and bermuda grass was 36, 21

Watson, Craig A.

70

Agronomy Notes Volume 32:11 November 2008  

E-print Network

..................................................................... Page 4 Special Local Needs 24(c) Pesticide Registrations ...Pages 4-5 Miscellaneous Calendar, Web Links for cool season winter annuals and small grains- Small grain may often respond to deep tillage (chisel plow seen as much as 15 bu/a yield increases on wheat due to deep tillage. Wheat prices are predicted

Watson, Craig A.

71

Multilevel programming of NOR flash EEPROMs by CHISEL mechanism  

Microsoft Academic Search

Multi-level (ML) storage is becoming an important option to achieve high-density flash EEPROMs. This is done by storing different amount of charges in the floating gate (FG) to reliably distinguish different levels and treating these levels as different combination of bits. Since large amount of charges need to be stored in FG for ML operation, faster programming is required so

D. R. Nair; S. Mahapatra; S. Shukuri; J. Bude

2004-01-01

72

A, Science Service Featurg aelemed upon receipt  

E-print Network

fighting Snow i n minter. must Often be reaoved from the tracks by shovel o r plow, lines t o protect from sand, just as thay are, i n many places, as a protection from drifting snow. Sand Fences a r e b u i l, 6s w e l l as acacia trees, have been used in California as protection against blowing sand

73

Earthworm additions increased short-term nitrogen availability and leaching in two grain-crop agroecosystems  

Microsoft Academic Search

Earthworms were added to enclosures in two agroecosystems to determine their influence on soil nitrogen availability and microbial activity, and to quantify their effect on the leaching of water and nitrogen through the surface soil. The two agroecosystems were a corn-soybean rotation with chisel-plow-disk tillage following corn (CS), and a corn-soybean-wheat-vetch rotation with ridge-tillage (CSW). In both agroecosystems, earthworm additions

Scott Subler; Christina M. Baranski; Clive A. Edwards

1997-01-01

74

Nitrous Oxide Emissions from Corn–Soybean Systems in the Midwest  

Microsoft Academic Search

Soil N2O emissions from three corn (Zea mays L.)-soybean (Glycine max (L.) Merr.) systems in central Iowa were measured from the spring of 2003 through February 2005. The three manage- ments systems evaluated were full-width tillage (fall chisel plow, spring disk), no-till, and no-till with a rye (Secale cereale L. 'Rymin') winter cover crop. Four replicate plots of each treatment

Timothy B. Parkin; Thomas C. Kaspar

2006-01-01

75

IMPORTANCE OF STARTER FERTILIZER COMPOSITION  

E-print Network

-till and no-till) · More frequent starter response at soil test K AdvantageTillage System Mallarino, Iowa 2Chisel-disk 4-5No-till 8Ridge-till -- bu/acre -- #12;No-till Corn/acre ---------------lb/acre MeanNo-till Moldboard plow Starter N-P2O5-K2O #12;Effect of tillage and soil test K on corn

Balser, Teri C.

76

Effect of tillage and farming system upon VAM fungus populations and mycorrhizas and nutrient uptake of maize  

Microsoft Academic Search

Low-input agricultural systems that do not rely on fertilizers may be more dependent on vesicular-arbuscular mycorrhizal [VAM] fungi than conventionally managed systems. We studied populations of spores of VAM fungi, mycorrhiza formation and nutrient utilization of maize (Zea mays L.) grown in moldboard plowed, chisel-disked or no-tilled soil under conventional and low-input agricultural systems. Maize shoots and roots were collected

L. Galvez; D. D. Douds; L. E. Drinkwater; P. Wagoner

2001-01-01

77

NITROGEN LEACHING LOSSES FROM CONVENTIONAL- AND NO-TILLAGE CORN  

E-print Network

Equilibrium-tension lysimeters were used to quantify year-round drainage, inorganic nitrogen (N) concentrations, and inorganic N leaching losses from undisturbed Plano silt loam soil (fine-silty, mixed, mesic Typic Argiudoll) of N-fertilized no-tillage and conventionally-tilled chisel plow corn (Zea mays L.) agroecosystems for 1996, 1997, and 1998. The chisel plowed corn agroecosystem consistently had greater drainage losses of water from its soil profile than a notillage corn agroecosystem over the 3 year period. Both fertilized tillage treatments maintained nitrate-N concentrations above the 10 mg L-1 safe drinking water standard for the majority of the three growing seasons monitored between 1996 and 1998. Inorganic N leaching losses were nearly the same for both fertilized corn tillage treatments for the first 2 years of this 3 year study. During the third year, inorganic N leaching losses from the fertilized no-tillage corn agroecosystem were greater than inorganic N leaching losses from the fertilized chisel plow corn agroecosystem.

Kristofor R. Brye; John Norman; Larry Bundy; Tom Gower

78

Teach Students to Dig for Understanding Using an Unexpected Technological Shovel  

ERIC Educational Resources Information Center

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…

Lake, Susan E. L.

2004-01-01

79

From dirt to shovels: fully automatic tool generation from ad hoc data  

Microsoft Academic Search

An ad hoc data sourceis any semistructured data source for which useful data analysis and transformation tools are not readi ly avail- able. Such data must be queried, transformed and displayed by systems administrators, computational biologists, financ ial analysts and hosts of others on a regular basis. In this paper, we demon- strate that it is possible to generate a

Kathleen Fisher; David Walker; Kenny Qili Zhu; Peter White

2008-01-01

80

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

PubMed Central

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

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

2012-01-01

81

Reducing adhesion of soil against loading shovel using bionic electro-osmosis method  

Microsoft Academic Search

Bionic electro-osmosis, a new method of reducing soil adhesion to soil-engaging components or parts of terrain machines, is presented. It is based on the anti-adhesion mechanism of the body surfaces of soil burrowing animals. The key feature of bionic electro-osmosis is to arrange a series of electric pole plates to create a non-smooth working surface. The static and dynamic effects

Luquan Ren; Qian Cong; Jin Tong; Bingcong Chen

2001-01-01

82

Analysis of productivity trends at a surface coal mine utilizing a shovel and bucket wheel excavator  

SciTech Connect

Surface coal mining productivity in the U.S. and Illinois has shown a general declining trend since 1969. The U.S. Department of Energy conducted an analysis in 1980 of the causes of declining productivity in different states. This paper presents a detailed analysis of changes in overall productivity and productivity in different functions such as overburden preparation, overburden stripping, reclamation, coal handling, etc. during the period 1970-1982. Statistical analysis techniques including multiple regression were utilized in the study.

Roethe, R.F.; Chugh, Y.P.

1983-03-01

83

Analysis of productivity trends at a surface coal mine utilizing a shovel and bucket wheel excavator  

Microsoft Academic Search

Surface coal mining productivity in the U.S. and Illinois has shown a general declining trend since 1969. The U.S. Department of Energy conducted an analysis in 1980 of the causes of declining productivity in different states. This paper presents a detailed analysis of changes in overall productivity and productivity in different functions such as overburden preparation, overburden stripping, reclamation, coal

R. F. Roethe; Y. P. Chugh

1983-01-01

84

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)

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.

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

2009-05-01

85

Broken Ground: Plowing and America's Cultural Landscape in the 1930s  

E-print Network

-in-Residence: John Steuart Curry and Soil Conservation .......................... 124 Epilogue: Marks on the Land .................................................................................................. 152 vi Figure List This list cites..., Kansas State Historical Society. Fig. 22. Grant Wood [Designer] (American, 1891-1942), Breaking the Prairie Sod (detail), 1935-37, oil on canvas, Iowa State University. Fig. 23. Grant Wood [Designer], When Tillage Begins Other Arts Follow...

Meyer, Kate

2011-05-31

86

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

NASA Astrophysics Data System (ADS)

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, ?. The force response of the granular material differs above and below the granular critical state, ?c, the volume fraction which corresponds to the onset of grain dilatancy. For ? ?c, FD rapidly rises to a maximum and then decreases over further displacement. The maximum force for ? >?c 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 ? >?c are associated with maxima in the spatially averaged shear strain field. For ? >?c the shear strain occurs in a narrow region in front of the plate, a shear band. For ? ?c, 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.

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

2014-04-01

87

High-speed plow mines 1043 tons per shift in 40 in-thick seam  

SciTech Connect

The operation of a high-speed plough in longwall working of a 40 in seam at Beckley No. 2 mine West Virginia is described. Conditions are not ideal, but an output of 1043 ton/shift is obtained, with the maximum for an 8-hour shift of 2750 tons of clean coal.

Campbell, J.I.

1984-11-01

88

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

SciTech Connect

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 both laboratory methods. The K{sub s} measurements and CDE parameters revealed no significant differences between tillages and treatments. In essence, the CT method and CDE model both proved to be useful methods to quantify macropores and estimate solute transport parameters, respectively. Breakthrough curves were generated to observe the initial and final breakthrough of solute response along the soil matrix.

Maria Ambert Sanchez

2003-12-12

89

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...

90

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

SciTech Connect

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.

Thacker, G.W.

1996-01-27

91

Keeping Corn Farmers Seeing Green As recently as 100 years ago, farmers plowed their fields with horses and  

E-print Network

of GOESR suggested they could even see revenue gains from selling excess water, a service valued at $61 to plant, when to harvest and sell their crops or what supplies to purchase before the planning season

92

PHYSICAL REVIEW E 89, 042202 (2014) Force and flow at the onset of drag in plowed granular media  

E-print Network

experiments, we use granular particle image velocimetry (PIV) to measure time resolved strain fields FD on a localized intruder in a granular medium composed of spherical glass particles. A flat plate associated with the horizontal motion of a plate started from rest. PIV experiments show that the maxima

Goldman, Daniel I.

93

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

NASA Astrophysics Data System (ADS)

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.

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

2014-08-01

94

How to get in and out of the skull: from tumi to "hammer and chisel" to the Gigli saw and the osteoplastic flap.  

PubMed

Making "holes in the skull" is an ancient art and by some is considered the second oldest profession in the world-the first being prostitution. Early surgeons, and later on neurosurgeons, devised a number of ingenious ways to make a hole in the skull or elevate a depressed skull fracture. Trephined skulls from antiquity have now been found in most parts of world, showing that the art of trephining is not only ancient but clearly widespread. Beginning with antiquity the author traces the development of this surgical skill by reviewing the various tools used and surgical designs to perform what is now called a craniotomy. PMID:24708162

Goodrich, James Tait

2014-04-01

95

Area terrace pit coal mining systems: volume 1technical and economic evaluation of terrace pit mining systems. Open file report (final) Sep 1977Jul 1980  

Microsoft Academic Search

This report is principally concerned with the engineering and economic feasibility of area surface coal mining systems other than draglines. This analysis evaluates shovel-trucks, shovel-crusher-conveyors, and shovel-rail excavation and haulage systems for an assortment of geologic environments and production rates in the Powder River Basin (PRB). Shovel-trucks, front-end loader-trucks, and shovel-crusher conveyors were studied in a multiseam, dipping geologic area

F. Leonard; C. Simon; M. Stoddard; M. Verma; M. White

1980-01-01

96

Area terrace pit coal mining systems: volume 2appendices. Open file report (final) Sep 1977Jul 1980  

Microsoft Academic Search

This report is principally concerned with the engineering and economic feasibility of area surface coal mining systems other than draglines. This analysis evaluates shovel-trucks, shovel-crusher-conveyors, and shovel-rail excavation and haulage systems for an assortment of geologic environments and production rates in the Powder River Basin (PRB). Shovel-trucks, front-end loader-trucks, and shovel-crusher-conveyors were studied in a multiseam, dipping geologic area of

F. Leonard; C. Simon; M. Stoddard; M. Verma; M. White

1980-01-01

97

Effect of Plowing Speed and Soil Moisture Content on the Voluminal Deformation of the Soil Body (Wplyw Szybkosci Orki i Wilgotnosci Gleby na Prace jej Odksztalcenia Objetosciowego).  

National Technical Information Service (NTIS)

The objective of the study was to investigate the work of the voluminal deformation of the soil body as a function of two essential factors, namely, the speed of the implement and the soil moisture content. The study is not, however, intended for a direct...

J. Haman

1975-01-01

98

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

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…

Lauzon, Glenn P.

2010-01-01

99

Nitrate leaching to shallow groundwater systems from agricultural fields with different management practices.  

PubMed

Monitoring the concentration of NO(3)-N from agricultural fields to the subsurface and shallow ground water resources have received considerable interest worldwide, since agriculture has been identified as a major source of nitrate-nitrogen (NO(3)-N) pollution of groundwater systems in intensively farmed watersheds. A study was conducted to quantify the impact of two tillage practices viz. chisel plow (CP) and no till (NT) with liquid swine manure application on nitrate leaching to the shallow ground water system under corn-soybean production system. This study is part of the long-term field experiments conducted at Iowa State University using completely randomized block design. The NO(3)-N concentrations in the shallow ground water were monitored at three depths viz., a network of subsurface drains at a depth of 1.2 m and piezometers at depths of 1.8 m and 2.4 m. Results of this study showed that the average NO(3)-N concentration during the study period was 16.1 mg l(-1), 14.4 mg l(-1) and 11.8 mg l(-1) at 1.2 m, 1.8 m and 2.4 m depths, respectively implying significant amount of NO(3)-N leaching past the subsurface drain depth of 1.2 m into the shallow groundwater but the NO(3)-N concentration decreases with the depth. The NO(3)-N concentrations in shallow groundwater were significantly higher under the chisel plow system in comparison with the no till method of tillage. Fall application of liquid swine manure caused more leaching in comparison with the spring application. Higher NO(3)-N concentration was observed under corn in comparison with the soybean plots. An in-depth analysis of the data showed a definite relationship between the NO(3)-N concentration in subsurface drain water at a depth of 1.2 m and shallow groundwater at depths of 1.8 m and 2.4 m depths. PMID:21785805

Nila Rekha, P; Kanwar, R S; Nayak, A K; Hoang, C K; Pederson, C H

2011-09-01

100

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

SciTech Connect

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 that landscape positions had small effect, but management, particularly manuring, had large and significant effects on soil strength and SOC concentration.

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

2005-04-01

101

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

NASA Astrophysics Data System (ADS)

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.

Woodard, H. J.

2004-12-01

102

Fungal colonization in soils with different management histories: modeling growth in three-dimensional pore volumes.  

PubMed

Despite the importance of fungi in soil functioning they have received comparatively little attention, and our understanding of fungal interactions and communities is lacking. This study aims to combine a physiologically based model of fungal growth with digitized images of internal pore volume of samples of undisturbed soil from contrasting management practices to determine the effect of physical structure on fungal growth dynamics. We quantified pore geometries of the undisturbed-soil samples from two contrasting agricultural practices, conventionally plowed (chisel plow) (CT) and no till (NT), and from native-species vegetation land use on land that was taken out of production in 1989 (NS). Then we modeled invasion of a fungal species within the soil samples and evaluated the role of soil structure on the progress of fungal colonization of the soil pore space. The size of the studied pores was > or =110 microm. The dynamics of fungal invasion was quantified through parameters of a mathematical model fitted to the fungal invasion curves. Results indicated that NT had substantially lower porosity and connectivity than CT and NS soils. For example, the largest connected pore volume occupied 79% and 88% of pore space in CT and NS treatments, respectively, while it only occupied 45% in NT. Likewise, the proportion of pore space available to fungal colonization was much greater in NS and CT than in NT treatment, and the dynamics of the fungal invasion differed among the treatments. The relative rate of fungal invasion at the onset of simulation was higher in NT samples, while the invasion followed a more sigmoidal pattern with relatively slow invasion rates at the initial time steps in NS and CT samples. Simulations allowed us to elucidate the contribution of physical structure to the rates and magnitudes of fungal invasion processes. It appeared that fragmented pore space disadvantaged fungal invasion in soils under long-term no-till, while large connected pores in soils under native vegetation or in tilled agriculture promoted the invasion. PMID:21774424

Kravchenko, Alexandra; Falconer, Ruth E; Grinev, Dmitri; Otten, Wilfred

2011-06-01

103

Tillage, Mulch and N Fertilizer Affect Emissions of CO2 under the Rain Fed Condition  

PubMed Central

A two year (2010–2012) study was conducted to assess the effects of different agronomic management practices on the emissions of CO2 from a field of non-irrigated wheat planted on China's Loess Plateau. Management practices included four tillage methods i.e. T1: (chisel plow tillage), T2: (zero-tillage), T3: (rotary tillage) and T4: (mold board plow tillage), 2 mulch levels i.e., M0 (no corn residue mulch) and M1 (application of corn residue mulch) and 5 levels of N fertilizer (0, 80, 160, 240, 320 kg N/ha). A factorial experiment having a strip split-split arrangement, with tillage methods in the main plots, mulch levels in the sub plots and N-fertilizer levels in the sub-sub plots with three replicates, was used for this study. The CO2 data were recorded three times per week using a portable GXH-3010E1 gas analyzer. The highest CO2 emissions were recorded following rotary tillage, compared to the lowest emissions from the zero tillage planting method. The lowest emissions were recorded at the 160 kg N/ha, fertilizer level. Higher CO2 emissions were recorded during the cropping year 2010–11 relative to the year 2011–12. During cropping year 2010–11, applications of corn residue mulch significantly increased CO2 emissions in comparison to the non-mulched treatments, and during the year 2011–12, equal emissions were recorded for both types of mulch treatments. Higher CO2 emissions were recorded immediately after the tillage operations. Different environmental factors, i.e., rain, air temperatures, soil temperatures and soil moistures, had significant effects on the CO2 emissions. We conclude that conservation tillage practices, i.e., zero tillage, the use of corn residue mulch and optimum N fertilizer use, can reduce CO2 emissions, give better yields and provide environmentally friendly options. PMID:24086256

Tanveer, Sikander Khan; Wen, Xiaoxia; Lu, Xing Li; Zhang, Junli; Liao, Yuncheng

2013-01-01

104

Tillage, mulch and N fertilizer affect emissions of CO2 under the rain fed condition.  

PubMed

A two year (2010-2012) study was conducted to assess the effects of different agronomic management practices on the emissions of CO2 from a field of non-irrigated wheat planted on China's Loess Plateau. Management practices included four tillage methods i.e. T1: (chisel plow tillage), T2: (zero-tillage), T3: (rotary tillage) and T4: (mold board plow tillage), 2 mulch levels i.e., M0 (no corn residue mulch) and M1 (application of corn residue mulch) and 5 levels of N fertilizer (0, 80, 160, 240, 320 kg N/ha). A factorial experiment having a strip split-split arrangement, with tillage methods in the main plots, mulch levels in the sub plots and N-fertilizer levels in the sub-sub plots with three replicates, was used for this study. The CO2 data were recorded three times per week using a portable GXH-3010E1 gas analyzer. The highest CO2 emissions were recorded following rotary tillage, compared to the lowest emissions from the zero tillage planting method. The lowest emissions were recorded at the 160 kg N/ha, fertilizer level. Higher CO2 emissions were recorded during the cropping year 2010-11 relative to the year 2011-12. During cropping year 2010-11, applications of corn residue mulch significantly increased CO2 emissions in comparison to the non-mulched treatments, and during the year 2011-12, equal emissions were recorded for both types of mulch treatments. Higher CO2 emissions were recorded immediately after the tillage operations. Different environmental factors, i.e., rain, air temperatures, soil temperatures and soil moistures, had significant effects on the CO2 emissions. We conclude that conservation tillage practices, i.e., zero tillage, the use of corn residue mulch and optimum N fertilizer use, can reduce CO2 emissions, give better yields and provide environmentally friendly options. PMID:24086256

Tanveer, Sikander Khan; Wen, Xiaoxia; Lu, Xing Li; Zhang, Junli; Liao, Yuncheng

2013-01-01

105

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)

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 (?b) 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 farmer? 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 (?b) but NT increased ?b in the superficial soil layers; ii) the more intensive the tillage system, the higher the change in the mean weight diameter (MP > CP > NT); iii) the unsaturated hydraulic conductivity (K) showed interaction with time and only was significantly different between the tillage systems in the year 2007; iv) the SOC was statistically higher in NT than in MP and CP, time had no significant effect on SOC, and vi) the tillage system did not affect the yields of the wheat-corn-sunflower crop rotation.

Aparicio, V.; Costa, J. L.

2012-04-01

106

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

NASA Astrophysics Data System (ADS)

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 (3.5 and 3.3 Mg ha-1 corresponding to 31Y and 80Y, respectively). The lower loss of carbon in 80Y compared to 30Y can be explained by the accumulation of stable SOC fractions produced by the burnt stubble. We conclude that current agricultural systems of the Rolling Pampas are not sustainable.

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

2012-04-01

107

NOVEL EXCAVATION TECHNOLOGIES FOR EFFICIENT AND ECONOMIC SURFACE MINING  

SciTech Connect

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, construct a field ready prototype and perform field testing at the surface mining sites. It is anticipated that 10% in energy savings including electricity (cable shovel) and fuel (hydraulic shovel) will be achieved by implementation of ISE technology.

Vladislav Kecojevic; Samuel Frimpong

2005-05-01

108

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

NASA Astrophysics Data System (ADS)

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.

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

2014-11-01

109

Manure composition and incorporation effects on phosphorus in runoff following corn biomass removal.  

PubMed

Greater demand for corn ( L.) stover for bioenergy use may lead to increased corn production acreage with minimal surface residue cover, resulting in greater risk for soil erosion and phosphorus (P) losses in runoff. A rainfall simulation study was conducted to determine the effects of spring-applied dairy cow () manure (none, in-barn composted, and exterior walled-enclosure pit) with >200 g kg organic solids content following fall corn biomass removal with and without incorporation (chisel plow [CP] and no-till [NT]) on sediment and P in runoff. Runoff was collected from a 0.83-m area for 60 min following the onset of rainfall simulation (76 mm h), once in spring and once in fall. Runoff dissolved reactive P (DRP) and dissolved organic P (DOP) concentrations were positively correlated with manure P rate and were higher in NT compared with CP. Conversely, sediment and particulate P (PP) concentrations in runoff were inversely correlated with manure P rate (and manure solids) and were higher in CP compared with NT. Runoff volume where no manure was applied was higher in NT than in CP in spring but similar in fall. The addition of manure reduced runoff volumes by an average of 82% in NT and 42% in CP over spring and fall. Results from this study indicate that surface application of dairy manure with relatively high solids content may reduce sediment and PP losses in runoff without increasing the risk of increased DRP and DOP losses in the year of application where corn biomass is harvested. PMID:22031580

Yagüe, María R; Andraski, Todd W; Laboski, Carrie A M

2011-01-01

110

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

PubMed

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 ?g L, much greater than its 3 ?g L MCL. Likewise, annual, flow-weighted alachlor concentration (MCL = 2 ?g L) was as high as 11.2 and 4.9 ?g 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 ?g L MCL and the highest, annual, flow-weighted concentration was 3.9 ?g 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

Shipitalo, Martin J; Owens, Lloyd B

2011-01-01

111

In-pit conveyors and crushers cut surface mining costs  

Microsoft Academic Search

This article discusses the increased interest in in-pit conveyors and equipment to enhance the production abilities of the main stripping tools--the draglines and the shovels. The advantages and limitations of various upper-overburden removal methods, including scrapers, bucket wheel excavators and conveyors, shovel trucks, shovel-hoppers and conveyors, draglines and draglinehoppers and conveyors are compared. Also discussed is the field experience of

Chironis

1985-01-01

112

vol. 169, no. 3 the american naturalist march 2007 Predicting Resource Partitioning and Community Organization  

E-print Network

is absent, mallards (Anas platy- rhynchos) and northern shovelers (Anas clypeata) should maximize of separating prey from detritus. Keywords: filter feeding, resource partitioning, ecomorphology, Anas, bill

113

WATERFOWL USE OF WASTEWATER PONDS ON THE IDAHO NATIONAL  

E-print Network

including ruddy ducks (Oxyura jamaicensis), redheads (Aythya americana), northern shoveler (Anas clypeata), northern pintail (A.. acuta), American wigeon (A.. americana), mallard (A. platyrhynchos), and green

114

Effects of Planter Attachments and Seed Treatment on Stands of Cotton.  

E-print Network

with Cer- esan, lime, and sulfur to determine the best treatment for cottonseed used for planting purposes. A knife or runner, furrow-opener gave better percentages of emer- gence and stands than narrow or wide shovel openers. The narrow shovel opener... with Cer- esan, lime, and sulfur to determine the best treatment for cottonseed used for planting purposes. A knife or runner, furrow-opener gave better percentages of emer- gence and stands than narrow or wide shovel openers. The narrow shovel opener...

Byrom, Mills H. (Mills Herbert); Smith, H. P. (Harris Pearson)

1942-01-01

115

78 FR 57205 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals  

Federal Register 2010, 2011, 2012, 2013

...Alignment (MALSR) modification. Design and construct wildlife/security...equipment--runway plow truck, chemical spreader, front end loader, plow truck, and skidsteer tractor with...loader. Extend taxiway Y--design and construct. Modify...

2013-09-17

116

Mammalogy Laboratory 6 -Rodents II: Castoridae, Geomyidae, Heteromyidae, Dipodidae, Muridae  

E-print Network

(Desert pocket mouse)* Dipodomys ordii (Ord's kangaroo rat) D. microps (Chisel-toothed kangaroo rat) D and Neotropical Genera: Heteromys, Liomys, Perognathus, Cheatodipus, Dipodomys, Microdipodops Material in Lab

Sullivan, Jack

117

Feeding methods, visual fields and vigilance in dabbling ducks (Anatidae)  

Microsoft Academic Search

Summary 1. Visual fields were determined in two species of dabbling ducks (Anatini): Shoveler Anas clypeata L. (planktivore whose foraging is guided mainly by tactile cues) and Wigeon A. penelope L. (herbivore whose foraging is guided mainly by visual cues). 2. The binocular fields of Shoveler and Wigeon are of similar maximum width (20 ° ), but they differ in

M. Guillemain; G. R. Martin; H. Fritz

2002-01-01

118

Say a prayer for Nipper, Michael Armstrong Say a prayer for Nipper  

E-print Network

to bury a dog. An inch of pine needles covered the ground, and one thrust of the shovel turned up pebbles outburst. Two if there was another setback. It was Kim's idea to bury the dog in the woods by Grandma's old wished she had. Kim stood silent, watching John fight his way down; the shovel scraping against rocks

Toronto, University of

119

March/April 2006 1 INTRODUCTION  

E-print Network

of higher production forcing the development of ever bigger, faster, and smarter cable shovels-scale physical prototype forces many OEMs to rely on the feedback of customers, often on an as-built basis, where in a revolutionary geometry that matches the range of motions of the shovel, designed to minimize wear, impact

Joseph, Tim Grain

120

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

SciTech Connect

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)

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

2009-05-15

121

JOHAN ARVIDSSON KARIN GUSTAFSSON THOMAS KELLER FACTSabout AgricultureOriginally published in Swedish; FAKTA Jordbruk No 8, 2003  

E-print Network

plough, chisel plough and disc implement under different moisture conditions and at different working depths. · The specific draught requirement was lowest for the mouldboard plough and highest for the chisel plough, especially under dry conditions. · The actual (average) tillage depth was considerably

122

Agron. Sustain. Dev. 29 (2009) 525533 c INRA, EDP Sciences, 2009  

E-print Network

and soil quality indicators. No-till, chisel and mouldboard ploughing was carried out for 23 years that the soil organic carbon concentration in the topsoil was greater under no-till than mouldboard ploughing was observed in the topsoil for chisel plough and no-till treatments compared to mouldboard ploughing. Water

Boyer, Edmond

123

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

SciTech Connect

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. However, the clay fraction of soil under native woodlot showed an indication for SOC saturation. The data presented in this study from all the three structural levels of SOC would be helpful for refining the conceptual pool definitions of the current soil organic matter prediction models.

Sindhu, Jagadamma [Oak Ridge National Laboratory (ORNL); Lal, Dr. Rattan [Ohio State University, The, Columbus

2010-08-01

124

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

SciTech Connect

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 very large pores associated with former root channels in NT and NS aggregates. Our findings indicate that mechanisms of macro-aggregate formation might differ in their importance in different land use and management practices.

Kravchenko, A.N.; Wang, A.N.W.; Smucker, A.J.M.; Rivers, M.L. (MSU); (UC)

2012-10-25

125

Open-pit equipment notebook  

SciTech Connect

Beds of consolidated material need to be drilled and blasted before successful excavation. In open-pit mining it is common to move fragmented material across to spoil piles by dragline, shovel, or bucketwheel excavator. One method recently introduced uses explosives to throw much of the overburden across the pit, thus reducing the amount of material needing rehandling. The increased cost of explosives must be balanced with the reduced cost of power needed by the prime excavator. The drill hole pattern and the use of high energy explosives require careful design. Making the choice between hydraulic excavators with a backhoe or front shovel, wheel loaders, and rope-operated shovels continues to be an interesting area of debate. While the rope-operated electric shovel is best for large output, smaller shovels are being replaced by hydraulic excavators for numerous reasons. One of the advantages of hydraulic excavators is that they weigh around half that of rope-operated shovels with the same size bucket. Another advantage is their mobility. They can move at a speed roughly twice that of a rope-operated shovel. Hydraulic excavators can successfully attack a solid face that needs blasting before being loaded by a wheel loader or rope-operated shovel. Neither the rope-operated shovel nor the wheel loader has the wrist-action of the hydraulic excavator. The backhoe's ability to dig below the level on which it is situated and to load trucks that are on the pit floor is important. Recently, many equipment manufacturers have introduced microprocessor-controlled systems for higher power and simpler operation. The choice between wheel loaders and hydraulic excavators should be based on site conditions.

Not Available

1984-12-01

126

Changes in Soil Organic Carbon Contents and Nitrous Oxide Emissions after Introduction of No-Till in Pampean Agroecosystems  

Microsoft Academic Search

We reviewed published results to estimate no-till effects on SOC and denitrification in the Argentine Pampas and the potential of no- till to mitigate the global warming effect. On an equivalent mass basis, 42 paired data sets were used for SOC comparisons of no-till vs. plow till (moldboard plow or disk plow), 18 paired data for comparison of no-till vs.

Haydée S. Steinbach; Roberto Alvarez

2006-01-01

127

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2011 CFR

...A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited from buying or...

2011-10-01

128

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2013 CFR

...A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited from buying or...

2013-07-01

129

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2013 CFR

...A hydraulic clam digger; (vi) A mechanical clam digger; (vii) A pot; (viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. (3) You are prohibited from buying or...

2013-10-01

130

50 CFR 36.31 - Recreational activities.  

Code of Federal Regulations, 2010 CFR

...collection methods which may result in disturbance of ground surface, such as the use of shovels, pickaxes, sluice boxes and dredges, are prohibited. The recreation activities specified in paragraphs (a) and (b) of this section may be prohibited or...

2010-10-01

131

78 FR 17350 - Foreign-Trade Zone 262-Southaven (Desoto County), Mississippi; Notification of Proposed...  

Federal Register 2010, 2011, 2012, 2013

...sweatshirts, jackets, gloves and hand warmers of textile materials, articles of fiberglass, fasteners, springs, wire, pins, spacers, guides, copper wire/tubing/fasteners, shovels, axes, pruners, shears, saws and related parts, hand tools,...

2013-03-21

132

50 CFR 91.4 - Eligible species.  

Code of Federal Regulations, 2012 CFR

...Northern Shoveler (Anas clypeata ) (f) Diving Ducks. (1) Canvasback (Aythya valisineria ) (2) Redhead (Aythya americana ) (3) Ring-necked Duck (Aythya collaris ) (4) Greater Scaup (Aythya marila ) (5) Lesser...

2012-10-01

133

50 CFR 91.4 - Eligible species.  

Code of Federal Regulations, 2010 CFR

...Northern Shoveler (Anas clypeata ) (f) Diving Ducks. (1) Canvasback (Aythya valisineria ) (2) Redhead (Aythya americana ) (3) Ring-necked Duck (Aythya collaris ) (4) Greater Scaup (Aythya marila ) (5) Lesser...

2010-10-01

134

50 CFR 91.4 - Eligible species.  

Code of Federal Regulations, 2013 CFR

...Northern Shoveler (Anas clypeata ) (f) Diving Ducks. (1) Canvasback (Aythya valisineria ) (2) Redhead (Aythya americana ) (3) Ring-necked Duck (Aythya collaris ) (4) Greater Scaup (Aythya marila ) (5) Lesser...

2013-10-01

135

50 CFR 91.4 - Eligible species.  

Code of Federal Regulations, 2011 CFR

...Northern Shoveler (Anas clypeata ) (f) Diving Ducks. (1) Canvasback (Aythya valisineria ) (2) Redhead (Aythya americana ) (3) Ring-necked Duck (Aythya collaris ) (4) Greater Scaup (Aythya marila ) (5) Lesser...

2011-10-01

136

Proceedings of IMECE2007 2007 ASME International Mechanical Engineering Congress and Exposition  

E-print Network

degrees of freedom as well as partitioning kinetic and potential energies in the overlapping domain weapon penetrating sand, the shoveling of sand by a tractor, and the flow of agricultural grains from

Regueiro, Richard A.

137

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...

138

33 CFR 155.215 - Discharge removal equipment for inland oil barges.  

...2) Non-sparking hand scoops, shovels, and buckets; (3) Containers suitable for holding recovered waste; (4) Emulsifiers for deck cleaning; and (5) Protective clothing. (c) The oil barge owner or operator may rely on equipment...

2014-07-01

139

33 CFR 155.220 - Discharge removal equipment for vessels carrying oil as secondary cargo.  

...2) Non-sparking hand scoops, shovels, and buckets; (3) Containers suitable for holding recovered waste; (4) Emulsifiers for deck cleaning; and (5) Protective clothing (c) The equipment and supplies must be ready for immediate use...

2014-07-01

140

33 CFR 155.220 - Discharge removal equipment for vessels carrying oil as secondary cargo.  

Code of Federal Regulations, 2011 CFR

...2) Non-sparking hand scoops, shovels, and buckets; (3) Containers suitable for holding recovered waste; (4) Emulsifiers for deck cleaning; and (5) Protective clothing (c) The equipment and supplies must be ready for immediate use...

2011-07-01

141

33 CFR 155.220 - Discharge removal equipment for vessels carrying oil as secondary cargo.  

Code of Federal Regulations, 2012 CFR

...2) Non-sparking hand scoops, shovels, and buckets; (3) Containers suitable for holding recovered waste; (4) Emulsifiers for deck cleaning; and (5) Protective clothing (c) The equipment and supplies must be ready for immediate use...

2012-07-01

142

33 CFR 155.220 - Discharge removal equipment for vessels carrying oil as secondary cargo.  

Code of Federal Regulations, 2013 CFR

...2) Non-sparking hand scoops, shovels, and buckets; (3) Containers suitable for holding recovered waste; (4) Emulsifiers for deck cleaning; and (5) Protective clothing (c) The equipment and supplies must be ready for immediate use...

2013-07-01

143

CGISS Seismic Field Equipment Check List Version 1.4, Seismograph  

E-print Network

# = [ ] [ ] [ ] 28. 8-gauge elc. PVC capsules # = [ ]. [ ] [ ] 29. 12-gauge shells # = [ ] [ ] [ ] 30. Wire for shot [ ]. Other Tools [ ] [ ] 35. Shovels [ ], rake [ ], and pick [ ]. [ ] [ ] 36. Tamping rod (PVC with cap). [ ] [ ] 37. PVC pipes (to keep holes open). [ ] [ ] 38. Geophone planters; small [ ] large [ ] [ ] [ ] 39

Barrash, Warren

144

Entitlement advantage : the balance of local knowledge and capital access in real estate entitlements  

E-print Network

Development is risky. The process of getting a shovel in the ground, steel into the sky, and rent checks into the bank involves distinct phases, each with their own risk and return profile. Generally considered the most ...

Kelley, Scott Edward

2007-01-01

145

Get to Know OSU Self-Guided Tour of Campus  

E-print Network

from WWI. The site was excavated by steam shovel but rocks and dirt were removed by horses with carts: one reflects the sea grant studies at OSU and the other is a WWI battlefield in France representing

Escher, Christine

146

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

147

26 CFR 48.4041-8 - Definitions.  

Code of Federal Regulations, 2010 CFR

...trucks used to carry loads at railroad stations, industrial plants, warehouses, etc. The term does not include farm tractors, trench diggers, power shovels, bulldozers, road graders or rollers, and similar equipment which does not carry or tow a...

2010-04-01

148

A comparison of alternative tillage practices and machinery management strategies in the Texas Rolling Plains  

E-print Network

/Swap Chisel/Deep rreIn Drill Q?sp Cultivator Ta??P Disk Tandac Dfsk Roll fns Cuitivator Ralllna Cultivator Rotary Hao cotton, sorghum, and wheat. The basic farm implements such as tractors, planters, and chisels are used for both tillage... investment for conventional till. The extra machinery used with conventional tillage are: (1) sweep cultivatorl (2) tandem disk; (3) rolling cultivatorl (4) rotary hoe; (5) deep chisel; and (6) a shredder. Reduced till/diking, on the other hand, uses a...

Maddox, Jim Dalton

2012-06-07

149

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

Microsoft Academic Search

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\\u000a and northern pintails. Protein did not fluctuate except in ruddy ducks whose protein mass increased over winter, suggesting\\u000a that some protein was catabolized

Ned H. Euliss; Robert L. Jarvis; David S. Gilmer

1997-01-01

150

21 CFR 878.4800 - Manual surgical instrument for general use.  

Code of Federal Regulations, 2010 CFR

...or disposable, intended to be used in various general surgical procedures. The device includes the applicator, clip applier, biopsy brush, manual dermabrasion brush, scrub brush, cannula, ligature carrier, chisel, clamp, contractor,...

2010-04-01

151

10 CFR 39.43 - Inspection, maintenance, and opening of a source or source holder.  

Code of Federal Regulations, 2010 CFR

...injection tools, source handling tools, storage containers, transport containers, and uranium sinker bars to ensure that the...licensee may not perform any operation, such as drilling, cutting, or chiseling, on the source holder unless the licensee...

2010-01-01

152

Draft Umatilla/Willow Subbasin Plan May 28, 2004 3.2.4 Terrestrial Focal Species Population Delineation and Characterization  

E-print Network

excavator and uses its strong chisel-shaped bill to construct nests and roost cavities and to find insects and fragmented sites (Dixon 1995 a,b). Individuals usually excavate nest cavities in snags, but have also been

153

ORIGINAL PAPER Management of herbicide-resistant Papaver rhoeas in dry  

E-print Network

and physical fallows, delayed seeding with barley, chemical and mechanical control, chisel cultivation seasons. Delayed seeding and the different fallows studied showed their effectiveness in reducing weed. Delayed seeding . Chemical fallow. Physical fallow. Harrowing . Mouldboard ploughing 1 Introduction

Boyer, Edmond

154

U N I V E R S I T Y O F C O L O R A D O A T B O U L D E R C A T A L O G Understand the unfamiliar  

E-print Network

: Student Services--p.50 Java's little helpers: Java Servlets--p.46 Beauty is just a chisel stroke away discussions that can only happen in a small-class setting. "I start my class with big questions. In answering

Mojzsis, Stephen J.

155

21 CFR 872.4565 - Dental hand instrument.  

...operative amalgam carrier, operative dental amalgam carver, surgical bone chisel, operative amalgam and foil condenser, endodontic...elevator, operative dental excavator, operative explorer surgical bone file, operative margin finishing file,...

2014-04-01

156

HDTE PROGRAM HAND TOOL LIST UAA is an EEO/AA employer and educational institution. The University of Alaska Anchorage is  

E-print Network

, groove-joint � 12" to 16" Pliers, needle nose - 6" to 9" Pliers, slip-joint - 8" Pliers, diagonal cutting and Universities. Page 2 of 2 (Rev) 7/18/11Final Copy Chisel and punch set Cold Chisels: �" and �" Center punch 5 �" - �" Socket set metric 12- point, 8 mm to 19mm. 3/8" Universal joint ball swivel 3/8" to �" drive socket

Pantaleone, Jim

157

Why is Soil SampleWhy is Soil Sample Depth ImportantDepth Important  

E-print Network

¾ depth of tillage No-till 6-7 in. 0-2 in. sample for pH in long-term no-till Influence of soil moisture fertilizer placement study. Started in 1997. Chisel, strip-till, no-till Continuous corn, corn/soybean w Sampling Comparisons Lancaster tillage x fertilizer placement study. No-till for 10+ years, 2 chisel, 1

Balser, Teri C.

158

Investigation of chip in vibration drilling  

Microsoft Academic Search

Up to the present, all published vibration drilling chip-breaking theories have considered that for zero-phase-difference axial vibration drilling (ZVD), major cutting-edge chip-breaking was impossible, and have not discussed the chisel-edge chip. In this paper, the extruding action of the rake and the flank have been considered, the possibility of the major cutting-edge chip-breaking in ZVD has been verified, the chisel-edge

Zhang Deyuan; Wang Lijiang

1998-01-01

159

Impacts of contrasting land-use history on composition, soils, and development of mixed-oak, coastal plain forests on Shelter  

E-print Network

contrasting land-use history affected: 1) tree species composition, size, and age structure; 2) soil chemistry and pH, the presence/absence of a plow layer (Ap) and for soil charcoal. Tree cores (N 5 130) were taken continually supported forests, have soils that are somewhat doughtier and less fertile, and lack a plowed

Abrams, Marc David

160

Cutting Through Soil  

NSDL National Science Digital Library

Students pretend they are agricultural engineers during the colonial period and design a miniature plow that cuts through a "field" of soil. They are introduced to the engineering design process and learn of several famous historical figures who contributed to plow design.

Integrated Teaching And Learning Program

161

Tillage impacts on soil microbial biomass C, N and P, earthworms and agronomy after two years of cropping following permanent pasture in New Zealand  

Microsoft Academic Search

Conversion of pasture land to crop rotation by plow tillage and reversion to pasture for replenishment of nutrients is a common practice in New Zealand. It is known that plow tillage decreases soil organic matter and causes biological degradation. The objective of this study was to investigate the effects of tillage practices on soil microbial biomass carbon (MBC), microbial biomass

T Aslam; M. A Choudhary; S Saggar

1999-01-01

162

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

NASA Astrophysics Data System (ADS)

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 Anderson-Darling test at each horizon or a combination of horizons for each soil type. RESULTS The LUC had a negative impact in the soil, reducing the SOC and TN stocks. The conversion from AC to V and OG involved the loss of the SOC stock (52.7% and 64.9% to V and OG respectively) and the loss of the TN stock (42.6% and 38.1% to V and OG respectively). The reduction of SOC by LUC, can be explained by a degraded process (due to vegetation losses and unsustainable soil management, which result in progressive impoverishment in the soil organic matter (OM) content, causing low productivity, which derived in unsuitable chemical properties) and by the reduced input of OM in cultivated soils, which reduced physical protection of soil and increased water erosion. However, 46 years of LUC had a positive effect in the soil, increasing the SR (in V and OG) of SOC, TN and C:N ratio (Parras-Alcántara et al., 2013). REFERENCES Parras-Alcántara, L., Martín-Carrillo, M., Lozano-García, B. 2013. Impacts of land use change in soil carbon and nitrogen in a Mediterranean agricultural area (Southern Spain). Solid Earth, 4: 167-177.

Parras-Alcántara, Luis; Lozano-García, Beatriz

2014-05-01

163

Feeding ecology of waterfowl wintering on evaporation ponds in California  

USGS Publications Warehouse

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.

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

1991-01-01

164

White Flame Energy switches to backhoes  

SciTech Connect

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.

Fiscor, S.

2005-06-01

165

G-MG A Ton of Snow  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Eric and Julianne are shoveling snow. After an hour of hard work, Eric remarks ''I bet we have shoveled more than a ton of snow.'' Explain what measure...

166

Screening Methods to Develop Alfalfa Germplasms Tolerant of Acid, Aluminum Toxic Soils  

E-print Network

. In the southeastern USA, Al and manganese toxicity and calcium deficiency are the most limiting soil factors can solve the problem of Al toxicity and calcium deficiency in the plow layer, but rooting problems

Parrott, Wayne

167

Integrated management of wild chamomile (Matricaria chamomilla L.) populations by tillage.  

PubMed

Nowadays, environmental, health and economic concerns encourage reviewing our weed management in agriculture. Integrated pest management is one key element in the development of weed management strategies less dependent from herbicides. To reach this goal, impact of different methods of tillage (Combinations of stubble cultivator and moldboard plow) on biology and dynamic of wild chamomile populations was studied in experimental plots of experimental farm of Gembloux Agro-Bio Tech. In summer 2012, wild chamomile densities were significantly lower in plots tilled with a moldboard plow. The use of a stubble cultivator did not significantly affect M. chamomilla density. In addition, we found higher wheat yields in plowed plots, indicating that the decrease in M. chamomilla densities reduces competition for wheat. These results show well long run impact of plowing and his effect on densities of wild chamomile and the seedbank. PMID:25151843

Jaunard, D; Monty, A; Henriet, F; De Proft, M; Mahy, G; Bodson, B

2013-01-01

168

Weekly Security Incident Log Period of Dec 16 -Dec 22, 2013  

E-print Network

responded to a report report of a motor vehicle collision involving a personal vehicle and a University snow plow. No injuries were reported. 12/17/2013 11:34 AM Motor Vehicle Incident 2013-002051 SCOTT LIBRARY

169

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

170

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

Federal Register 2010, 2011, 2012, 2013

...Taxiway R extension and road relocation--design. Runway 5/23 pavement rehabilitation--design. Property acquisition--parcel 40...phase I. Purchase airport snow removal truck/plow. Design and construct noise mitigation...

2012-05-10

171

Review of the Impacts of Crumb Rubber in Artificial Turf Applications  

E-print Network

Sports Turf Managers Association (2006). Suggested EquipmentSports Turf Managers Association (2006) 5) ?Synthetic Turf Maintenance Equipment? (Equipment: special rubber blade snow plow Page 14 References for Table 2.1 1) Sports

Simon, Rachel

2010-01-01

172

A Monthly Safety Bulletin The Office of the NASA  

E-print Network

on the ramp. We taxied forward to where we believed we would be able to turn to runway 9. We tried to stay to find the runway well-plowed--but where did all that plowed snow end up? The Captain found out: s The runway was snowplowed, with dry pavement and about 7-8 foot snowbanks. The width was NOTAMed at 60 feet

173

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

PubMed

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

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

2013-05-15

174

Soil microbial activity, nitrogen cycling, and long-term changes in organic carbon pools as related to fallow tillage management  

Microsoft Academic Search

Two experiments were established in 1969 and 1970 near Sidney, NE, to determine the effect of moldboard plow (plow), sub-tillage (sub-till), and no-tillage (no-till) fallow management on soil properties, biological activities, and carbon and nitrogen cycling. One experiment was on land which had been broken from sod in 1920, seeded to crested wheatgrass [Agropyron cristatum (L.) Gaertn.] from 1957 to

J. W Doran; E. T Elliott; K Paustian

1998-01-01

175

Effect of Tillage on Alfalfa N Credit to Winter Wheat  

E-print Network

. Tillage effects? · 4. Too much N? #12;Experimental variables: · Tillage No-till or moldboard plow · Fall N lb/a Fall N 0 Fall N 30 lb/a Fall N Wheatyield(bu/a) 0 20 40 60 Spring N rates (lb/a) NO-TILL Wheatyield(bu/a) 0 20 40 60 NO-TILL MOLDBOARD PLOW Spring N rates (lb/a) #12;Yield response of wheat

Balser, Teri C.

176

Crop production and soil water storage in long-term winter wheat–fallow tillage experiments  

Microsoft Academic Search

Soil water is the major limiting factor in dryland crop production in the Central Great Plains. No-till fallow management increases soil water storage and reduces soil erosion potential. Two experiments were initiated in 1969 and 1970 near Sidney, NE to compare effects of moldboard plow (Plow), sub-tillage (Sub-till) and no-tillage (No-till) fallow systems on winter wheat (Triticum aestivum L.) grain

Drew J. Lyon; Walter W. Stroup; Randall E. Brown

1998-01-01

177

Seasonal variation of root distribution of irrigated, field-grown Russet Burbank potato  

Microsoft Academic Search

Root density of irrigated, field-grown Russet Burbank potatoes grown on Plainfield loamy sand was determined periodically\\u000a from soil core samples during the 1973 growing season. Total root length and weight also were measured.\\u000a \\u000a Under these growing conditions, the roots essentially were restricted to the plow layer in this soil, decreasing rapidly below\\u000a this depth. The root density in the plow

D. B. Lesczynski; C. B. Tanner

1976-01-01

178

Normatives of changes in the physical properties of chernozems in the forest-steppe zone of European Russia under conditions of their intensive agricultural use  

NASA Astrophysics Data System (ADS)

Normatives of changes in the physical properties of plowed typical and leached heavy loamy and light clayey chernozems under their intensive agricultural use are developed for two major provinces of the forest-steppe zone of European Russia. The limits of the optimal, permissible, and critical values of the physical properties of the plow layer for crop growth are determined. It is shown that the variation in the physical properties of the plow layer of chernozems is determined not only by the zonal-provincial features but also by the period and type of their use and the farming standards. In the plow layer, the natural differences in the physical properties of chernozems at the subtype level are significantly leveled by agrotechnical measures and the similar requirements of cultivated crops. Upon high farming standards, the physical properties of plowed chernozems on fields with high and moderate fertility levels remain close to the optimum or permissible values. The technogenic compaction of the plow layer of chernozems of different textures in the forest-steppe zone and the corresponding decrease in the yield of cereals are predicted on the basis of known models. The developed normatives of changes in the physical properties of cultivated chernozems can be applied to assess the modern state of the physical conditions of these soils and the tendencies of their alteration; they can serve as a basis for improving regional systems of land use.

Kuznetsova, I. V.; Utkaeva, V. F.; Bondarev, A. G.

2013-12-01

179

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

PubMed Central

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

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

2014-01-01

180

Homemade Games… how to make and play.  

E-print Network

the sawed end. Remove the sawed material with a chisel or rip saw. Drill a hole in the center of the axle. Screw the axle to the end -- of the broomstick so that the top of axle is flush with the square surface of the end of the broomstick. Screw... the sawed end. Remove the sawed material with a chisel or rip saw. Drill a hole in the center of the axle. Screw the axle to the end -- of the broomstick so that the top of axle is flush with the square surface of the end of the broomstick. Screw...

Moore, Lucille H.; Johnson, Eloise T.

1957-01-01

181

A Late Bronze Age shipwreck at Ulu Burun: preliminary analysis (1984-1985 excavation campaigns)  

E-print Network

deep-bar chisel KW 536. 1: 2 39. Bronze chisel KW 566. 1:2 40. Bronze drill bit KW 579 ' 1:2 41. Bronze drill bit KW 381. 1: 2 . 83 . . 83 . . 85 . 87 87 . . . 87 42. Bronze tongs KW 378. L. 42 cm. 43. Bronze sword KW 275. L. 45. 4 cm. 44.... Bronze sword KW 301. L. 4 5. 5 cm. 45. Bronze sword KW 155. 1: 2 46. Bronze dirk KW 189. 1: 2 47. Bronze dagger KW 621. 1: 2 48. Bronze dagger KW 189. 1: 2 . 92 . . 95 95 . 98 49. Bronze arrowhead KW 572. 1: 2 . . . 100 50. Bronze javelin...

Pulak, Cemal

2012-06-07

182

Technology for Institutional Enrollment, Communication, and Student Success  

ERIC Educational Resources Information Center

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…

Salas, Grace; Alexander, Julie S.

2008-01-01

183

Stringless Paving Quality Eric Kopinski, MoDOT  

E-print Network

and shovel � Grade Stakes #12;Construction Inspection � Concrete #12;MIT Scan #12;MIT Scan � Provides X, Y, and Z location of dowel bar � Estimated measurement error is 0.12" � Provides in place data � Can

184

1 INTRODUCTION Oil sand has unique properties exhibits performance  

E-print Network

larger units as mining operations move towards in-pit extractive technologies, some of these units are barely able to float on the ground surface, having maximized the available footprint area accounting being cycled on the ground surface. In a given footprint position, a shovel may cycle the same ground

Joseph, Tim Grain

185

Study of the use of personal equipment in low coal. Experiments on personal equipment for low seam coal miners: II. Effect of size and weight of battery pack on performance. Phase II report, number 3. Open file report 1 Jan 79-1 Sep 79  

Microsoft Academic Search

The objective of this study was to determine optimal personal equipment design for use in low coal based on ergonomic, biomechanic, and safety considerations. This report describes three experiments that were conducted to determine the effects of size and weight of battery packs. The first experiment tested the sensitivity of task measures; that is, workers performed locomotion, shoveling, cart pushing,

M. Sanders; G. Krohn; D. Wick; K. Volkmer; B. Beith

1980-01-01

186

192 Yellow-billed Pintail neck ring Wildfowl (2006) 56: 192-196Wildfowl & Wetlands Trust  

E-print Network

related species (Harrison 1953, 1955). For example, Northern Shoveler Anas clypeata males in eclipse plumage in the Yellow-billed Pintail Anas georgica ROBERT E. WILSON1, THOMAS H. VALQUI2 & KEVIN G phylogenetic information. A partial white neck ring was observed in Yellow-billed Pintail Anas georgica

McCracken, Kevin G.

187

AN EPIZOOTIC OF AVIAN BOTULISM IN A PHOSPHATE MINE SETTLING POND IN NORTHERN FLORIDA  

Microsoft Academic Search

Type C botulism was determined to be the cause of an epizootic among waterfowl and shorebirds in a phosphate mine settling pond in northern Florida during May and June of 1979. Several hundred birds, the most common of which were American coots (Fulica americana), wood ducks (Aix sponsa), common gallinules (Gallinula chloropus), and northern shovelers (Anas clypeata) were afflicted over

J. FORRESTER; LLKARL C. WENNER; FRANKLIN H. WHITE; C. GREINER; L WAYNE R. MARION; JAMES E. THUL; GERMAN A. BERKHOFF

188

TRANSMISSION OF Sarcocystis rileyi TO THE STRIPED SKUNK  

Microsoft Academic Search

Musculature containing grossly visible cysts of Sarcocystis rileyi from northern shoveler (Anas clypeata) ducks was fed to the striped skunk (Mephitis mephitis). Skunks used were determined to be Sarcocystis free,thechallengedskunk became infected and shed both sporulated oocysts and free sporocysts in the feces. The prepatent period was 15 days and the patent period 50 days. Oocysts were fully sporulated when

ROBERT J. WICHT

189

Punchy, Munchy...Culinary Curriculum  

ERIC Educational Resources Information Center

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)

Schmidt, Carolee; And Others

1977-01-01

190

19. Photocopied August 1978. CANAL SECTION I, LOOKING EAST, 1900, ...  

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

19. Photocopied August 1978. CANAL SECTION I, LOOKING EAST, 1900, WITH SEVERAL PARTIALLY SUBMERGED STEAM SHOVELS SHOWN IN THE FLOODED CANAL. ONE OF THE TEMPORARY BRIDGES CONSTRUCTED OVER THE CANAL RIGHT -OF-WAY IS VISIBLE IN THE BACKGROUND. (39) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

191

HISTORICAL CHANGES IN VERTEBRATE SPECIES COMPOSITION APPENDIX J  

E-print Network

sponsa X X X Northern Pintail Anas acuta X X American Wigeon Anas americana X X X Northern Shoveler Anas californica X X Golden Eagle Aquila chrysaetos X X Great Blue Heron Ardea herodias X X X Lesser Scaup Aythya affinis X X Ring-necked Duck Aythya collaris X X X Greater Scaup Aythya marila X Canvasback Aythya

Standiford, Richard B.

192

Common Waterfowl in the Southeast Common name1,2  

E-print Network

Anas clypeata canvasback Aythya valisineria redhead Aythya americana ring-necked duck Aythya collaris discors gadwall Anas strepera American wigeon Anas americana northern pintail Anas acuta northern shoveler lesser scaup Aythya affinis greater scaup Aythya marila common goldeneye Bucephala clangula Barrow

Gray, Matthew

193

BIOL 427 species list, Page 1 Biology 427: List of main species to learn  

E-print Network

Wigeon Anas americana 30 Northern Pintail Anas acuta 30 Northern Shoveler Anas clypeata 32 Greater Scaup Aythya marila 36 Lesser Scaup Aythya affinis 36 Surf Scoter Melanitta perspicillata 42 Black Scoter Melanitta americana 42 White-winged Scoter Melanitta fusca 42 Bufflehead

Irwin, Darren

194

Jared Verner, Edward C. Beedy, Stephen L. Granholm, Lyman V. Ritter, and Edward F. Toth This chapter offers information on the status, distri-  

E-print Network

B017 Redhead Aythya americana B018 Ring-necked Duck Aythya collaris B019 Canvasback Aythya cyanoptera B014 American Wigeon Anas americana B015 Northern Shoveler Anas clypeata B016 Wood Duck Aix sponsa valisineria B020 Lesser Scaup Aythya affinis B021 Barrow's Goldeneye Bucephala islandica B022 Bufflehead

Standiford, Richard B.

195

August 27, 2010 -Issue 22Purdue Cooperative Extension Service http://extension.entm.purdue.edu/pestcrop/index.html  

E-print Network

Faghihi, Kiersten Wise, Christian Krupke and Virginia Ferris) Soybean Cyst Nematode: Soybean Cyst Nematode. The white and yellow female bodies, which form the cysts when they die, should be visible on the soybean roots. To see these cysts, dig the soybean plants out of the ground with a shovel and dip in a bucket

Ginzel, Matthew

196

Natural Resources: Digging Soil  

NSDL National Science Digital Library

It's not hard to captivate children with the world of soil--many of them already love "dirt." Plus, exploring soil requires no special equipment or field trips. Soil is everywhere, with only a shovel or trowel required. You just might need some help deciph

Mayes, Valynda

2009-11-01

197

How far can the freshwater bryozoan Cristatella mucedo disperse in duck guts?  

Microsoft Academic Search

Statoblasts of Cristatella mucedo were fed to two duck species, pintail (Anas acuta) and shoveler (A. clypeata), to assess whether endozoochorous dispersal is responsible for the metapopulation structure of this bryozoan. Eight individuals (four per duck species) were force-fed 500 statoblasts each. The number of intact statoblasts retrieved from the ducks faeces up to 48 hours after ingestion and their

Iris Charalambidou; Luis Santamaría; Jordi Figuerola

2003-01-01

198

Official BirdLife South Africa "Bird list for South Africa" Common Name Scientific Name Endemic? Introduced? Migrant? Vagrant?  

E-print Network

acuta vagrant Garganey Anas querquedula vagrant Hottentot Teal Anas hottentota Southern Pochard Netta Teal Anas capensis African Black Duck Anas sparsa Mallard Anas platyrhynchos introduced Yellow-billed Duck Anas undulata Cape Shoveler Anas smithii Red-billed Teal Anas erythrorhyncha Northern Pintail Anas

de Villiers, Marienne

199

Surface mine comes of age. [Alabama  

SciTech Connect

The production record of Calvert and Marsh Coal Co., USA, has been set by the use of draglines for stripping instead of shovels and trucks, and with a hydraulic excavator loading from the seam instead of rubber-tyred front-end loaders.

Not Available

1981-08-01

200

Efficiency - key to equipment selection  

Microsoft Academic Search

The purpose of this paper is to establish a reliable method of choosing between the dragline or power shovel and the bucket wheel excavator using efficiency as one of the main selection criteria. Using efficiency as the most important criterion will afford a basis for choosing the proper tool for the job. This allows all phases of the machine usage

Gozon

1985-01-01

201

Application of a total system mine simulator to coal stripping. volume V. application to an Illinois mine. Open file report (final) 30 June 1975-31 March 1977  

Microsoft Academic Search

In this report, the application of the open pit materials handling simulator (OPMHS) to a mine located in Illinois using bucket wheel excavator (BWE) and a stripping shovel in tandem for overburden removal is described. The specific objective of the study is to demonstrate the application of the simulator to analyze mine planning and scheduling problems and to generate and

R. V. Ramani; S. Bandopadhyay; C. B. Manula

1977-01-01

202

Probability Technique to Predict Power Demand of Excavator Group  

Microsoft Academic Search

A method is presented for determining the total power demand for a localized area where excavators such as shovels, draglines, and bucket-wheel excavators operate. It is based upon the synthesis of a probability distribution function developed from readily available and measurable parameters. Therefore, the results are a true reflection of real working conditions and are computationally efficient. The method is

Stanislaw Minasiewicz; Gordon S. Hope; Om P. Malik

1986-01-01

203

Excavation and transportation in surface coal mining - the recent past and near future  

Microsoft Academic Search

Approximately 50 to 60% of the total operating cost in a surface mine is consumed in the excavation and transportation of the mined mineral, consequently, incentive to reduce cost in this area remains high. Although the use of traditional equipment such as shovel\\/trucks, draglines, front-end loaders and scrapers is the mainstay of surface mining, the coal industry is now beginning

Singhal

1984-01-01

204

Productivity and equipment selection in surface mining of oil sands  

Microsoft Academic Search

A variety of mining equipment is used in the mining of oil sands by surface mining. This includes bucket wheel excavators, draglines, hydraulic shovels and off-highway trucks. This paper examines the existing mining schemes and equipment used. Peculiarities of oil sands surface mining and their influence on equipment selection, utilization and mining schemes are described. Recent developments undertaken to improve

R. K. Singhal; R. J. Kolada; T. I. Vladut

1985-01-01

205

Complete Genome Sequence of a Reassortant H14N2 Avian Influenza Virus from California  

PubMed Central

We report the complete genome sequence of a reassortant H14N2 avian influenza virus isolated in 2011 from a northern shoveler in California. This introduced Eurasian subtype acquired seven segments from North American viruses and circulated in the Pacific Flyway 1 year after its detection in the Mississippi Flyway. PMID:23908286

Schobel, Seth; Dugan, Vivien G.; Halpin, Rebecca; Lin, Xudong; Wentworth, David E.; Lindsay, LeAnn L.; Mertens, Eva; Plancarte, Magdalena

2013-01-01

206

William Menke, Ph. D. Professor of Earth and Environmental Sciences  

E-print Network

means is available (plane, helicopter, train, car, jeep, bus, ship, ferry, canoe, zodiac raft, horse, shoveling snow, sewing, exterminating vermin, etc. 1.2.3.2 Minor maintenance, including electric, mountain climbing, spelunking, surveying, etc. 1.2.6 Operation of field equipment, including seismometers

Menke, William

207

Incubation length of dabbling ducks  

USGS Publications Warehouse

We collected unincubated eggs from wild Mallard (Anas platyrhynchos), Gadwall (A. strepera), Blue-winged Teal (A. discors), and Northern Shoveler (A. clypeata) nests and artificially incubated them at 37.5??C. Average incubation lengths of Mallard, Gadwall, and Northern Shoveler eggs did not differ from their wild-nesting counterparts, but artificially incubated Blue-winged Teal eggs required an additional 1.7 days to hatch, suggesting that wild-nesting teal incubated more effectively. A small sample of Mallard, Gadwall, and Northern Shoveler eggs artificially incubated at 38.3??C hatched 1 day sooner, indicating that incubation temperature affected incubation length. Mean incubation length of Blue-winged Teal declined by 1 day for each 11-day delay in nesting, but we found no such seasonal decline among Mallards, Gadwalls, or Northern Shovelers. There is no obvious explanation for the seasonal reduction in incubation length for Blue-winged Teal eggs incubated in a constant environment, and the phenomenon deserves further study. ?? The Cooper Ornithological Society 2005.

Wells-Berlin, A. M.; Prince, H.H.; Arnold, T.W.

2005-01-01

208

The importance of protected areas as nocturnal feeding grounds for dabbling ducks wintering in western France  

Microsoft Academic Search

We studied the diurnal and nocturnal habitat use of wintering dabbling ducks (Anas spp.) in two protected areas of an internationally important winter quarter in western France. The waterbodies of the reserves are heavily used by ducks during daylight hours, and 3–55% of these birds used the reserves at night: >50% of shoveler (A. clypeata), 20% of granivorous ducks (mallard

Matthieu Guillemain; Hervé Fritz; Patrick Duncan

2002-01-01

209

2006 Haulage & Loading Conference: big equipment, big crowd  

SciTech Connect

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.

NONE

2006-06-15

210

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

211

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

212

Environmental and Resource Studies Program Equipment Available For Use in ERS Courses  

E-print Network

(battery tester) power inverter solar panel and solar charge controller Audio-Visual Equipment camera trailer, boat safety kits and lifejackets containers for sample collection plant press callipers (tree secchi disk shovels sieves, soil (partial sets) soil sampling kits soil samplers (auger, shaft bits

Fox, Michael

213

Optimization of Dispatching Criteria for Open-Pit Truck Haulage System Design Using Multiple Comparisons with the Best and Common Random Numbers  

Microsoft Academic Search

This paper considers simulation of truck dispatching system designs using maximum expected production of the truck-shovel system as the measure of performance. Two methods are utilized, multiple comparisons with the best (MCB) and the combination of MCB and the variance reduction technique known as common random numbers (CRN). These two techniques are compared via simulation experiments. The results show that

Bozo Kolonja; D. R. Kalasky; Jan M. Mutmansky

1993-01-01

214

Optimization of dispatching criteria for open-pit truck haulage system design using multiple comparisons with the best and common random numbers  

Microsoft Academic Search

This paper considers simulation of truck dispatching system designs using maximum expected production of the truck-shovel system as the measure of perfommnce. Two methods are utilized, multiple comparisons with the best (MCB) and the combination of MCB and the variance reduction technique known as common random numbers (CRN). These two techniques are compared via simulation experiments. The results show that

Bozo Kolonja; David R. Kalasky; Jan M. Mutmansky

1993-01-01

215

Transplanting wildings in small revegetation projects  

Microsoft Academic Search

Transplanting individuals from natural communities in the vicinity may provide an economical and rapid means of revegetating small, severely disturbed sites. We transplanted individuals of two bunchgrass and two shrub species from adjacent sagebrush steppe onto disturbed sites at the Idaho National Engineering Laboratory. Plants and a shovel?full of soil were moved in late fall. Survival was high for all

Mark L. Shumar; Jay E. Anderson

1987-01-01

216

Beach Hopper Bonanza Grade Level: Second Grade  

E-print Network

Beach Hopper Bonanza Grade Level: Second Grade Developers: Jan Ward, Merry Lojkovic, Kara Davidson the characteristics, behavior, and anatomy of beach hoppers. !" Examine the relationships between the beach hopper (transparent) !" 1-2 buckets !" sieves !" shovel !" small plastic container with lid to hold beach hoppers

217

Surveys of wetlands and waterbirds in Cagayan valley, Luzon, Philippines  

Microsoft Academic Search

In November 2001 and January 2002, we searched the entire Cagayan valley, north-east Luzon, Philippines for wetlands and congre- gations of waterbirds. Five wetlands were identified that held substantial numbers of waterbirds. Important numbers of the endemic Philippine Duck Anas luzonica (Vulnerable) were observed at two lakes, as well as large numbers of Wandering Whistling-duck Dendrocygna arcuata, Northern Shoveler Anas

MERLIJN VAN WEERD; JAN VAN DER PLOEG

2004-01-01

218

Extreme Cold: A Prevention Guide to Promote Your Personal Health and Safety  

MedlinePLUS

... mb to h eat if th ey p art ici pat e in str en uo us ... l yo ur lo cal hea lth dep art men t t o s ee if th ere ... follow your doctor’s advice about shoveling snow or performing other hard work in the cold. Otherwise, if ...

219

Fossil Humankind and Other Anthropoid Primates of China  

Microsoft Academic Search

More than 70 sites have yielded human fossils in China. They are attributed to Homo sapiens erectus and Homo sapiens sapiens. The earliest one is possibly about 1.7 Ma. A series of common morphological features, including shovel-shaped incisors and flatness of the face, characterize them. There is a morphological mosaic between H. s. erectus and H. s. sapiens in China.

Xinzhi Wu

2004-01-01

220

Big Jobs: Planning for Competence  

ERIC Educational Resources Information Center

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,…

Jones, Nancy P.

2005-01-01

221

Isolation of phyllosilicate-iron redox cycling microorganisms from an illite-smectite rich hydromorphic soil.  

PubMed

The biogeochemistry of phyllosilicate-Fe redox cycling was studied in a Phalaris arundinacea (reed canary grass) dominated redoximorphic soil from Shovelers Sink, a small glacial depression near Madison, WI. The clay size fraction of Shovelers Sink soil accounts for 16% of the dry weight of the soil, yet contributes 74% of total Fe. The dominant mineral in the clay size fraction is mixed layer illite-smectite, and in contrast to many other soils and sediments, Fe(III) oxides are present in low abundance. We examined the Fe biogeochemistry of Shovelers Sink soils, estimated the abundance of Fe redox cycling microorganisms, and isolated in pure culture representative phyllosilicate-Fe oxidizing and reducing organisms. The abundance of phyllosilicate-Fe reducing and oxidizing organisms was low compared to culturable aerobic heterotrophs. Both direct isolation and dilution-to-extinction approaches using structural Fe(II) in Bancroft biotite as a Fe(II) source, and O(2) as the electron acceptor, resulted in recovery of common rhizosphere organisms including Bradyrhizobium spp. and strains of Cupriavidus necator and Ralstonia solanacearum. In addition to oxidizing biotite and soluble Fe(II) with O(2), each of these isolates was able to oxidize Fe(II) in reduced NAu-2 smectite with [Formula: see text] as the electron acceptor. Oxidized NAu-2 smectite or amorphous Fe(III) oxide served as electron acceptors for enrichment and isolation of Fe(III)-reducing microorganisms, resulting in recovery of a strain related to Geobacter toluenoxydans. The ability of the recovered microorganisms to cycle phyllosilicate-Fe was verified in an experiment with native Shovelers Sink clay. This study confirms that Fe in the native Shovelers Sink clay is readily available for microbial redox transformation and can be cycled by the Fe(III)-reducing and Fe(II)-oxidizing microorganisms recovered from the soil. PMID:22493596

Shelobolina, Evgenya; Konishi, Hiromi; Xu, Huifang; Benzine, Jason; Xiong, Mai Yia; Wu, Tao; Blöthe, Marco; Roden, Eric

2012-01-01

222

Isolation of Phyllosilicate-Iron Redox Cycling Microorganisms from an Illite-Smectite Rich Hydromorphic Soil  

PubMed Central

The biogeochemistry of phyllosilicate–Fe redox cycling was studied in a Phalaris arundinacea (reed canary grass) dominated redoximorphic soil from Shovelers Sink, a small glacial depression near Madison, WI. The clay size fraction of Shovelers Sink soil accounts for 16% of the dry weight of the soil, yet contributes 74% of total Fe. The dominant mineral in the clay size fraction is mixed layer illite–smectite, and in contrast to many other soils and sediments, Fe(III) oxides are present in low abundance. We examined the Fe biogeochemistry of Shovelers Sink soils, estimated the abundance of Fe redox cycling microorganisms, and isolated in pure culture representative phyllosilicate–Fe oxidizing and reducing organisms. The abundance of phyllosilicate–Fe reducing and oxidizing organisms was low compared to culturable aerobic heterotrophs. Both direct isolation and dilution-to-extinction approaches using structural Fe(II) in Bancroft biotite as a Fe(II) source, and O2 as the electron acceptor, resulted in recovery of common rhizosphere organisms including Bradyrhizobium spp. and strains of Cupriavidus necator and Ralstonia solanacearum. In addition to oxidizing biotite and soluble Fe(II) with O2, each of these isolates was able to oxidize Fe(II) in reduced NAu-2 smectite with NO3- as the electron acceptor. Oxidized NAu-2 smectite or amorphous Fe(III) oxide served as electron acceptors for enrichment and isolation of Fe(III)-reducing microorganisms, resulting in recovery of a strain related to Geobacter toluenoxydans. The ability of the recovered microorganisms to cycle phyllosilicate–Fe was verified in an experiment with native Shovelers Sink clay. This study confirms that Fe in the native Shovelers Sink clay is readily available for microbial redox transformation and can be cycled by the Fe(III)-reducing and Fe(II)-oxidizing microorganisms recovered from the soil. PMID:22493596

Shelobolina, Evgenya; Konishi, Hiromi; Xu, Huifang; Benzine, Jason; Xiong, Mai Yia; Wu, Tao; Blothe, Marco; Roden, Eric

2012-01-01

223

THE GREATER CARBON SEQUESTRATION IN NO-TILL SOILS DEPENDS UPONITS DISTRIBUTION WITH DEPTH  

Microsoft Academic Search

Soil organic matter (SOM) storage in agricultural soils has a significant effect not only on productivity but can also ameliorate the greenhouse effect via atmospheric CO2sequestration. Severalreports show a larger accumulation of SOM in the top layer of soils under no till (NT) practices but no significant differenceswith respect to soils under chisel till (CT) when deeper layers are considered.

M. Diaz-Zorita; J. H. Grove

224

Characterization of soil physical properties and organic matter under long-term primary tillage in a humid climate  

Microsoft Academic Search

Chisel ploughing is considered to be a potential conservation tillage method to replace mouldboard ploughing for annual crops in the cool-humid climate of eastern Canada. To assess possible changes in some soil physical and biological properties due to differences in annual primary tillage, a study was conducted for 9 years in Prince Edward Island on a Tignish loam, a well-drained

M. R. Carter

1996-01-01

225

For more information, contact Eileen Kladivko, 765-494-6372, kladivko@purdue.edu Nitrate Leaching into Tile Drains at SEPAC  

E-print Network

in spring. Tile drains (4 in. diameter perforated plastic drain tube) were installed in 1983 at three spacings (16, 33, and 66 ft.) at a depth of 2.5 ft. and a slope of 0.4%. From 1984 - 1993, continuous corn was grown with spring chisel tillage, while in 1994 a no-till soybean- corn rotation was begun with a winter

Jackson, Scott A.

226

EastThe Magazine of easT Carolina UniversiTy Battlefield  

E-print Network

!The ones I've watched him use to chisel a bedroom suite out of a pine log! And there are his gloves! His here.We like to feel pride in ourTar Heel institutions, in the way we always put education first, even

227

Developing Efficient Conservation Tillage Systems for Potato and  

E-print Network

;Effect of tillage and cover crop sweet corn whole plant N, 2003 Cover Crop Moldboard Chisel Para-till Avg provided minimal residue and N trapping because of limited growth Plant population not affected: Objectives Compare crop response between conventional and conservation tillage Evaluate the effectiveness

Balser, Teri C.

228

SPRING 2013 OVARIAN CANCER HAS MYSTIFIED  

E-print Network

life 03_ NEWS BITES What food crop requires the most phosphorus to produce and how do corrupt acts come.TheLearning Environments Across Disciplines project uses technology and games to challenge long-held beliefs about into products. 26_ HOW TO BUILD A COMPUTER-ASSISTED ICE SCULPTURE IN SIX EASY STEPS Out with the chisel

Shoubridge, Eric

229

Long-term tillage and maize monoculture effects on a tropical Alfisol in western Nigeria. I. Crop yield and soil physical properties  

Microsoft Academic Search

A wide range of tillage methods (e.g. mouldboard ploughing, discing, harrowing, chiselling, notill, ridge till, and their combinations) are used for continuous maize (Zea mays L.) cropping in western Nigeria without the benefits of experimental data on their comparative effects on soil properties and crop response. Therefore, the main objective of this experiment was to evaluate the impact of a

R. Lal

1997-01-01

230

Soil microbial communities under conventional-till and no-till continuous cotton systems  

Microsoft Academic Search

Soil management practices affect soil microbial communities, which in turn influence soil ecosystem processes. In this study, the effects of conventional- (fall disking, chiseling and spring disking, field cultivation) and no-tillage practices on soil microbial communities were examined under long-term continuous cotton (Gossypium hirsutum L.) systems on a Decatur silt loam soil. Soil samples were taken in February, May, and

Y. Feng; A. C. Motta; D. W. Reeves; C. H. Burmester; E. van Santen; J. A. Osborne

2003-01-01

231

EVALUATING CORN STARTER FERTILIZER PROGRAMS  

E-print Network

soil tests (ridge-till and no-till) · More frequent starter response at soil test K Broadcast or Planter-band K Tillage System Advantage -- bu/acre -- Ridge-till 8 No-till 4-5 Chisel-disk 2 Mallarino, Iowa #12;No-till Corn Yield Response to Starter Fertilizer in Selected Experiments Location

Balser, Teri C.

232

What is strip-tillage Strip-tillage is defined as less than full-width  

E-print Network

often associated with no-till slot planting. Research studies have shown a potential for earlier growth, and increased yield when compared to no-till. Figure 1 shows the soil temperature measured at two to those where chiseled, and about 5o C warmer than no-till. Emergence and early growth were delayed

Balser, Teri C.

233

FERTILITY PLACEMENT FOR CONSERVATION TILLAGE  

E-print Network

TO DETERMINE NUTRIENT NEED SAMPLING DEPTH VARIES · MULCH TILLAGE: 3/4 DEPTH OF TILLAGE · NO-TILL; STRIP TEST K (ppm) 0 to 2 2 to 4 4 to 6 6 to 8 NO-TILL CHISEL WOLKOWSKI, 2000 #12;BANDING vs. BROADCAST

Balser, Teri C.

234

IS FALL TILLAGE FOLLOWING SOYBEAN HARVEST NECESSARY?1/  

E-print Network

residue. A no-till treatment featured slot planting with a Kinze planter (soil engagement overall residue an average of 10-12% with the greatest reduction in CC where residue was highest in no-till, WI, 2000.* Crop rotation* Chisel No-till Strip-till Average

Balser, Teri C.

235

EFFECTIVE RESIDUE-TILLAGE-MANURE  

E-print Network

, 24, 48 t/a (N BALANCED) CHISEL, DISK, ROW CLEARING, NO-TILL #12;ARLINGTON TILLAGE/MANURE STUDY, 1995;ARLINGTON TILLAGE/MANURE STUDY, 1995 48 t/a MANURE, NO-TILL #12;48 t/a STRAW DAIRY MANURE N0-TILL ~90

Balser, Teri C.

236

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

ERIC Educational Resources Information Center

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…

Lane Community Coll., Eugene, OR.

237

The Hymn to Hermes and the Athenian Altar of the Twelve Gods  

Microsoft Academic Search

Newly observed congruencies between Homeric Hymn (4) to Hermes and circumstances in Peisistratid Athens lend credence to Norman O. Brown's hypothesis that the hymn was motivated by the establishment of the Altar of the Twelve Gods in Athens in 522\\/521 B.C. Relevant details in the hymn include the use by Hermes of a gluphanos, a sculptor's chisel, his unmotivated journey

Richard W. Johnston; David Mulroy

2009-01-01

238

The Hymn to Hermes and the Athenian Altar of the Twelve Gods  

Microsoft Academic Search

:Newly observed congruencies between Homeric Hymn (4) to Hermes and circumstances in Peisistratid Athens lend credence to Norman O. Brown's hypothesis that the hymn was motivated by the establishment of the Altar of the Twelve Gods in Athens in 522\\/521 B.C. Relevant details in the hymn include the use by Hermes of a gluphanos, a sculptor's chisel, his unmotivated journey

Richard W. Johnston; David Mulroy

2009-01-01

239

Saltbush Leaves: Excision of Hypersaline Tissue by a Kangaroo Rat  

Microsoft Academic Search

Dipodomys microps climbs into shrubs and harvests leaves of the halophyte Atriplex confertifolia throughout the year. The epidermal vesicles of these leaves are high in electrolyte concentration, but the specialized photosynthetic parenchyma which is arranged concentrically about the vascular bundles is low in electrolytes and high in starch. The lower incisors of D. microps are broad, flattened anteriorly, and chisel-shaped

G. J. Kenagy

1972-01-01

240

Soil porosity characteristics and water movement under zero tillage in silty soils in Argentinian Pampas  

Microsoft Academic Search

The objective of this study was to identify pore characteristics (quantity, distribution, stability and orientation of pores) that condition water dynamics under continuous zero tillage (ZT) on silty soils of the Argentinian Rolling Pampas. Soil properties were analyzed under continuous chisel plough (CP) and ZT treatments from three trials with different duration and crop sequence. The following soil properties of

M. C. Sasal; A. E. Andriulo; M. A. Taboada

2006-01-01

241

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

NASA Astrophysics Data System (ADS)

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.

Nadav, Itamar; Tarchitzky, Jorge; Chen, Yona

2012-11-01

242

Debris transport around high-speed snowplows  

NASA Astrophysics Data System (ADS)

The distribution of airborne debris around high-speed snowplows affects visibility and thus road safety. A combination of calculations, windtunnel experiments, and road trials are presented to provide knowledge of debris distributions and to obtain understanding of the mechanisms that can reduce suspended debris. Measurements obtained around windtunnel models show the influence of a variety of plow geometries on the location of debris around plowing trucks. Debris trajectories were calculated around plows with and without overplow deflectors by solution of Reynolds-averaged Navier-Stokes equations with cutting-edge and particle-tracking models. Calculations extrapolated windtunnel results over the wide range of snow conditions from light powder to slushy ice. Road trials compared visibility of conventional and modified snowplows with image analysis that quantified visible area, contrast and color intensity. In full scale tests, snow did not blow overtop of plow configurations that had trap angles less than 50 degrees, as predicted in windtunnel and computational results. Packing and junction flaps deflected discharge snow back into the consolidated discharge stream and decreased the amount of loose debris. Side-mounted hopper vanes kept rearward- facing surfaces clearer and made rear lighting and signage more effective. The visible area of high-speed snowplows outfitted with overplow deflector, packing flap, junction flap and hopper vanes was measured to be more than 50% larger than conventional plows for following motorists in all wind conditions and this was linked to reductions in the quantity of debris in the downstream snow cloud.

Nakhla, Hany Kamel

2001-08-01

243

The Chemical Composition of Some Soils of Angelina, Brazoria, Cameron, Cherokee, Delta, Lamar, Hidalgo, Lavaca, Montgomery, Nacogdoches, Robertson, Rusk, Webb and Wilson Counties.  

E-print Network

of the Colorado River bottoms; the dkainage is not very eared cultivation* of this soil requires much care, as the soil when :I-y sticky and bakes hard when dry. It should not be plowed too soon after a rain or when too wet, as it then breaks into clods... of the Colorado River bottoms; the dkainage is not very eared cultivation* of this soil requires much care, as the soil when :I-y sticky and bakes hard when dry. It should not be plowed too soon after a rain or when too wet, as it then breaks into clods...

Fraps, G. S. (George Stronach)

1909-01-01

244

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

SciTech Connect

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.

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

1996-04-01

245

A long-term infiltrometer study in southern Idaho, U.S.A.  

NASA Astrophysics Data System (ADS)

Nine years of infiltration measurements were made over a 12-yr. period on a big sagebrush ( Artemisia tridentata) site in southern Idaho that was plowed and seeded in the fall of 1968. Results of the study thus far indicate that plowing caused an initial significant decline in infiltration rates. Grazing, started in 1970, did not further reduce infiltration but seasonal trends were eliminated and there was no recovery of infiltration. Exclosures indicate it would take at least six years for complete recovery of infiltration rates, assuming no grazing. Suggestions are given for the use of deterministic models in predicting infiltration rates based on grazing intensity.

Gifford, Gerald F.

1982-09-01

246

Control of Weeds in Rice Fields.  

E-print Network

. With the chief eource of twed seed eliminated, thc problem of weed control becomes less Zifficult. In addition to the elimination of weeds the broad, sloping levee has several other features to recommend its use. Plowing and other field operations may be done.... With the chief eource of twed seed eliminated, thc problem of weed control becomes less Zifficult. In addition to the elimination of weeds the broad, sloping levee has several other features to recommend its use. Plowing and other field operations may be done...

Laude, H. H. (Hilmer Henry)

1918-01-01

247

Autoerotic fatalities with power hydraulics.  

PubMed

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

O'Halloran, R L; Dietz, P E

1993-03-01

248

Design data and economic relationships for beef cattle feed handling and processing systems  

E-print Network

:. " 38" 55LC 80. )CCC. C- Augers with no 4 inch 6 inch Power Shovel tors, each 125. 00 300. 00 1800. 00 TR 130 '"Large Unit - 2500 Head Ope-arion &yvrSma11 Uni t - 500 Head Operat ion "RB f: V LRBOR. rEED O' RND EQ, ?ENE ttFQu &E&EN"5...:. " 38" 55LC 80. )CCC. C- Augers with no 4 inch 6 inch Power Shovel tors, each 125. 00 300. 00 1800. 00 TR 130 '"Large Unit - 2500 Head Ope-arion &yvrSma11 Uni t - 500 Head Operat ion "RB f: V LRBOR. rEED O' RND EQ, ?ENE ttFQu &E&EN"5...

Allen, William Samuel

2012-06-07

249

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

250

Study of the use of personal equipment in low coal. Experiments on personal equipment for low seam coal miners: I. Comparison of 10\\/60 and standard self-rescue devices. Phase II report, number 1. Open file report 1 Jan 79-1 Sep 79  

Microsoft Academic Search

The objective of this study was to determine optimal personal equipment design for use in low coal based on ergonomic, biomechanic, and safety considerations. This report compares a proposed 10\\/60 'piggyback' 02-generating, self-rescue unit with the standard CO self-rescue unit with respect to work task interference. A simulated low seam coal mine was constructed and workers performed locomotion, shoveling, cart

M. Sanders; G. Krohn; K. Volkmer; D. Wick; H. Miller

1980-01-01

251

Twelve contiguous spinous process fracture of cervico-thoracic spine.  

PubMed

The clay-shoveler's fracture is an isolated avulsion fracture of the lower cervical or upper thoracic spinous process. Among them, multiple spinous process fractures are very rare. We present 34-year-old male patient who have multiple spinous process fractures with twelve contiguous levels of cervico-thoracic spine (from C4 to T8) after motorcycle accident. This case is multiple isolated spinous process fractures with good clinical outcome. PMID:25346773

Han, Seong Rok; Sohn, Moon Jun

2014-09-01

252

Measuring Rules!  

NSDL National Science Digital Library

Have fun playing these games! Once you have gotten the hang of how to play the game, move to the hardest level possible and see if you can win! What do you way in Space? Find out in How Much Do I Really Weigh?. This is your new dog, is he big or little. Measure him to find out How much does your Poodle weigh?. Grab a shovel and Start Digging! ...

Dean, Ms.

2008-04-08

253

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

PubMed

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 in pochard and unrelated in shoveler, implying that fledging success is not always a reliable measure of LRS. PMID:15138877

Blums, Peter; Clark, Robert G

2004-06-01

254

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

USGS Publications Warehouse

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.

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

1996-01-01

255

Inexpensive "Do It Yourself" Spill Kit Commercially available spill kits range in cost from $70 to more than $240. You can cut your cost and  

E-print Network

need to move the kit around.) 7.75 7 - 14 (20) One gallon lock-type plastic bags 1.00 1 - 3 (50 letters or other permanent label. Fill 10 or 11 of the gallon size lock-type plastic bags with absorbent sq. ft. of 5 mil plastic sheeting and a fold-up military type shovel. Item Cost $ Range $ (1) 32

256

Byrd Polar Research Center, The Ohio State University Image of the Location  

E-print Network

and Poles Large Enough for Five People B ­ Ice Core Drill C ­ Heavily Insulated Coat with Hood and Matching Insulated Pants D ­ Sleeping Bag E ­ Large Sheet of Orange Plastic F - Helmet G - Crampons H ­ Stove with Can of Fuel I ­ Ice Ax J - Shovel K ­ Map of the Area L ­ Metal Can with Sealable Lid M ­ Bottle

Howat, Ian M.

257

Direct dumping mining systems – Application and economics  

Microsoft Academic Search

In the following a brief history is given of direct dumping systems with emphasis on cross-pit stackers. Excavating equipment alternatives such as bucket wheel excavators or shovel and crusher combinations are examined. The stacker is often referred to as a cross-pit spreader (XPS) or cross-pit conveyor (CPC—. The XPS system has gained in popularity and is more and more frequently

J. ERodenberg; S. R. Winzer; D. J. Nordin

1988-01-01

258

Soviet surface mining  

Microsoft Academic Search

Years of emphasis on the development of underground equipment have left the surface coal mining sector lacking in modern, domestically built, high-capacity machines. According to the Soviet coal industry, the following equipment is needed to meet the ambitious production increases planned for the future: (1) 20 cubic meter (26 cubic yard) shovels; (2) 12.5 and 20-cubic-meter (16 and 26-cubic-yard) hydraulic

Sealy

1981-01-01

259

A review on existing opencast coal mining methods within Australia  

Microsoft Academic Search

Currently almost 65 % of the coal in Australia is being produced by opencast mining methods. Mining equipments such as draglines,\\u000a dredgers or bucket wheel excavators, trucks and shovels, and dozers are the main equipments employed for overburden removal\\u000a and coal extraction. The choice of equipment for a particular mine depends on geological, geotechnical and economic factors\\u000a and other site

B. Scott; P. G. Ranjith; S. K. Choi; Manoj Khandelwal

2010-01-01

260

A method of determination of the losses of refractory raw material in complicated non-transportation systems of mining  

Microsoft Academic Search

In refractory raw material open pit mines in conducting stripping work a combined system of mining including working of the top and center benches using a transport or transport-dump system and of the base bank using a complicated nontransport system with the use of ESh-6\\/45, ESh-10\\/70, and ESh-15\\/90 power shovels has found wide use. At present in the open-pit mines

V. G. Popov; V. I. Pikalova

1987-01-01

261

Wonder Underground  

NSDL National Science Digital Library

In this activity, learners engage in the joy of discovery as they dig to uncover the wonders that can be found underground. Learners use tools (gardening shovels and sifters) to find natural items like twigs and litter like bottle caps buried in topsoil. Learners use scientific skills to collect, classify, describe and record their findings. Use this activity to talk about the difference between non-living and living things and/or littering.

Museum, Chicago C.

2008-01-01

262

Defensive burying in rodents: ethology, neurobiology and psychopharmacology  

Microsoft Academic Search

Defensive burying refers to the typical rodent behavior of displacing bedding material with vigorous treading-like movements of their forepaws and shoveling movements of their heads directed towards a variety of noxious stimuli that pose a near and immediate threat, such as a wall-mounted electrified shock-prod. Since its introduction 25 years ago by Pinel and Treit [J. Comp. Physiol. Psychol. 92

Sietse F. De Boer; Jaap M. Koolhaas

2003-01-01

263

Temporal flexibility of reproduction in temperate-breeding dabbling ducks  

USGS Publications Warehouse

I compared nesting intervals during three consecutive years in five species of temperate-nesting dabbling ducks (Mallard [Anas platyrhynchos], Northern Pintail [Anas acuta], Northern Shoveler [Anas clypeata], Blue-winged Teal [Anas discors], Gadwall [Anas strepera]) and assessed whether differences existed in timing of refractoriness. Most nesting by females of all five species ended by the summer solstice. Nesting ended earliest for Northern Shovelers and Northern Pintails and latest for Gadwalls. Some Mallards, Blue-winged Teal, and Gadwalls continued to nest into mid- and late summer, whereas Northern Shovelers and Northern pintails did not. Mallards, Blue-winged Teal, and Gadwalls accounted for 99% (81 of 82) of flightless broods resulting from nests initiated during mid- or late summer in North Dakota and 98% (58 of 59) of flightless juveniles shot on or after 1 October by a random sample of duck hunters from across the United States. Early cessation of breeding by Northern Shovelers may have evolved in response to the species' limited flexibility in diet. Photorefractory mechanisms that limit most breeding to spring presumably evolved in response to severe constraints on reproductive success when nesting continued through summer(e.g. mortality of late-hatched young and molting females due to low temperatures). Interspecific differences in photosensitivity may account for variation in timing of cessation of nesting in late spring, but controlled experiments are needed to assess the possible role of non-photic influences. My results suggest that the refractory mechanisms controlling length of the breeding in temperate-nesting dabbling ducks are more varied and complex than previously thought, with non-photic influences (e.g. water conditions, food availability, food quality) having a larger role than indicated by earlier research.

Krapu, G.L.

2000-01-01

264

Improving haul truck productivity  

SciTech Connect

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.

Fiscor, S.

2007-06-15

265

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

266

Investigating the Site of Newton's Laboratory in Trinity College, Cambridge  

E-print Network

-shovels, funnels, crucibles, glass ‘phials’, and a diverse set of materi- als, including metals such as antimony, bismuth, iron, copper and lead, and re- agents such as oil of vitriol (sulphuric acid), aqua fortis (nitric acid), fullers earth and vitriol [copper... (II) sulphate]. Every chemical laboratory has always produced significant quantities of waste materials: broken glassware and earthen- ware (retorts, flasks, containers, etc.), cracked crucibles, unused or spent re- agents, solid or liquid reaction products, etc...

Spargo, P E

267

Aridlands Ecology Lab Protocol Modified: 2010.01.08, S. Castle  

E-print Network

diameter rebar (2 pieces per silt fence) Pocket knife Flat blade spade or shovel 3lb sledge hammer 3 x 3ft of the transect. Find the most prominent water flow path in the area. Water flow paths must be less than 1m, as to not disturb water flow paths. #12;Aridlands Ecology Lab Protocol Modified: 2010.01.08, S. Castle 2. Using

Barger, Nichole

268

Twelve Contiguous Spinous Process Fracture of Cervico-Thoracic Spine  

PubMed Central

The clay-shoveler's fracture is an isolated avulsion fracture of the lower cervical or upper thoracic spinous process. Among them, multiple spinous process fractures are very rare. We present 34-year-old male patient who have multiple spinous process fractures with twelve contiguous levels of cervico-thoracic spine (from C4 to T8) after motorcycle accident. This case is multiple isolated spinous process fractures with good clinical outcome. PMID:25346773

Sohn, Moon Jun

2014-01-01

269

Phosphorus and Potassium Distribution in Soil Following Long-Term Deep-Band Fertilization in Different Tillage Systems  

Microsoft Academic Search

Tillage and fertilizer placement affect soil-test P (STP) and K (STK) distribution in topsoil but little is known about stratification after deep banding. This study investigated lateral and vertical STP and STK stratification after deep-banding fertilizers for corn (Zea mays L.) and soybean (Glycine max (L.) Merr.) managed with no-till or chisel-disk tillage. Soil samples were collected from selected plots

Antonio P. Mallarino; Rogerio Borges

2006-01-01

270

Socioeconomics of alternative tillage systems  

Microsoft Academic Search

Socio-economic as well as technical aspects of conventional (autumn mouldboard plough), full-width no plough (chisel plough) and no tillage systems are compared from the viewpoints of farmers, non-farm public, and society as a whole. Either form of conservation tillage helps to increase protective surface residues, reduce soil erosion, maintain long-term soil productivity and reduce sediment and phosphorus loadings into watercourses.

D. Peter Stonehouse

1997-01-01

271

Effect of tillage and field condition on soil physical properties, cane and sugar yields in Vertisols of Kenana Sugar Estate, Sudan  

Microsoft Academic Search

An experiment was conducted to study the effect of heavy disc harrowing in combination with chisel ploughing to depths of 10, 20, and 30cm, on soil physical properties, cane yield, and sugar yield. The experiment was executed in two non-fallow, two semi-fallow and one fallow field conditions, in Kenana Sugar Estate, Sudan.Results showed that the final surfaces for all tillage

E. A Hammad; M. I Dawelbeit

2001-01-01

272

Runoff losses of sediment and phosphorus from no-till and cultivated soils receiving dairy manure.  

PubMed

Managing manure in no-till systems is a water quality concern because surface application of manure can enrich runoff with dissolved phosphorus (P), and incorporation by tillage increases particulate P loss. This study compared runoff from well-drained and somewhat poorly drained soils under corn (Zea mays, L.) production that had been in no-till for more than 10 yr. Dairy cattle (Bos taurus L.) manure was broadcast into a fall planted cover crop before no-till corn planting or incorporated by chisel/disk tillage in the absence of a cover crop. Rainfall simulations (60 mm h(-1)) were performed after planting, mid-season, and post-harvest in 2007 and 2008. In both years and on both soils, no-till yielded significantly less sediment than did chisel/disking. Relative effects of tillage on runoff and P loss differed with soil. On the well-drained soil, runoff depths from no-till were much lower than with chisel/disking, producing significantly lower total P loads (22-50% less). On the somewhat poorly drained soil, there was little to no reduction in runoff depth with no-till, and total P loads were significantly greater than with chisel/disking (40-47% greater). Particulate P losses outweighed dissolved P losses as the major concern on the well-drained soil, whereas dissolved P from surface applied manure was more important on the somewhat poorly drained soil. This study confirms the benefit of no-till to erosion and total P runoff control on well-drained soils but highlights trade-offs in no-till management on somewhat poorly drained soils where the absence of manure incorporation can exacerbate total P losses. PMID:21043281

Verbree, David A; Duiker, Sjoerd W; Kleinman, Peter J A

2010-01-01

273

2010-2011 Participating Products Products Worth 1 Point  

E-print Network

Great Erase® Bold Great Erase® Grip Great Erase® Grip XL Great Erase® Retractable Great EraseTM Low Odor Pen RT Retractable Ball Pen Wite-Out® Brand Mini Tape BIC® Highlighters Brite Liner® Brite Liner® + Brite Liner® Grip Brite Liner® Grip Chisel Brite Liner® Retractable BICTM Mailing Labels BICTM Print

Palmeri, Thomas

274

Pocket Gophers  

Microsoft Academic Search

Thirty-four species of pocket gophers, represented by five genera, occupy the western hemisphere. In the United States there are 13 species and three genera. The major features differentiating these genera are the size of their forefeet, claws, and front surfaces of their chisel-like incisors. Thomomys have smooth-faced incisors and small forefeet with small claws. Northern pocket gophers (Thomomys talpoides) are

Ronald M. Case; Bruce A. Jasch

1994-01-01

275

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

276

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

NASA Astrophysics Data System (ADS)

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.

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

2012-04-01

277

Supplement to Diagnosis and Management of Salinity Problems in Irrigated Pecan Production: Salt Leaching  

E-print Network

the leaching equation predicts, one has to examine the soil. Improve Soil Permeability Various methods are available for increasing soil permeability and salt leaching, including chiseling, trenching, and chemical amendments (Miyamoto and Storey... water soluble chemicals and polymers for improving permeability (e.g., Wildman et al., 1988, Wallace et al., 1986). The effectiveness of chemical amendment depends on physical and chemical properties of soil and water quality. Sodded floor...

Miyamoto, S.

278

Fallowing practices, soil water storage, plant- available soil nitrogen accumulation and wheat performance in South West Queensland  

Microsoft Academic Search

Radford, B.J., Gibson, G., Nielsen, R.G.H., Butler, D.G., Smith, G.D. and Orange, D.N., 1992. Fal- lowing practices, soil water storage, plant-available soil nitrogen accumulation and wheat perform- ance in South West Queensland. Soil Tillage Res., 22: 73-93. The effects of tillage frequency (conventional, reduced and zero), primary tillage implement (disc, blade and chisel plough), stubble management (retention and removal), gypsum

B. J. Radford; G. Gibson; R. G. H. Nielsen; D. G. Butler; G. D. Smith; D. N. Orange

279

T"hy"la Issue 7  

E-print Network

to moveuntil they hadboth sat down.They travelled in silence, Spock sitting upright whilethe Ahfar lounged backcomfortably and studied /s| the Vulcan intensely. Spock endured it without reacting, staring straight ahead at the elaborately- patterned wall. '1...,chisel-carved in geometric patterns of interlocking rec tangles. "Here," Vbos said as he opened the door."Noramil's Mirror. Look well, Spock." He ushered Spock inside and then withdrew, closingthe door firmlybehind him. At the sound of the door shut ting, Spock turned...

Multiple Contributors

2013-11-27

280

Soil organic carbon and fertility interactions affected by a tillage chronosequence in a Brazilian Oxisol  

Microsoft Academic Search

No-till (NT) adoption is an essential tool for development of sustainable agricultural systems, and how NT affects the soil organic C (SOC) dynamics is a key component of these systems. The effect of a plow tillage (PT) and NT age chronosequence on SOC concentration and interactions with soil fertility were assessed in a variable charge Oxisol, located in the South

João Carlos de Moraes Sá; Carlos Clemente Cerri; Rattan Lal; Warren A. Dick; Marisa de Cassia Piccolo; Brigitte Eduardo Feigl

2009-01-01

281

Soil erosion and agricultural sustainability David R. Montgomery*  

E-print Network

Soil erosion and agricultural sustainability David R. Montgomery* Department of Earth and Space conventionally plowed agricultural fields average 1­2 orders of magnitude greater than rates of soil production indicates that, considered globally, hill- slope soil production and erosion evolve to balance geologic

Montgomery, David R.

282

Decline and Renewal in the Heartland  

Microsoft Academic Search

The arrival of European Americans in the Upper Midwest in the middle of the nineteenth century led to dramatic changes in the region's ecology. In what was perhaps the most rapid and extensive degradation of a natural ecosystem in human history, in the space of 50 years settlers plowed under millions of acres of the native tallgrass prairie and replaced

Jonathan Andelson

283

Folksong in the Classroom. Volume VI. 1985-86.  

ERIC Educational Resources Information Center

As this nation's settlers and immigrants built homes, railroads, and plowed the fields, they told their story through songs and ballads. Transmitting this cultural heritage is the goal of this volume containing songs, bibliographies, teaching ideas, and record and book reviews. These three issues focus on the songs of the railroads, the farmers,…

Scott, John A., Ed.; Seidman, Laurence I., Ed.

1986-01-01

284

Self-revegetation of disturbed ground in the deserts of Nevada and Washington  

Microsoft Academic Search

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

W. H. Rickard; R. H. Sauer

1982-01-01

285

Magic Tutorial #7: Netlists and Routing John Ousterhout  

E-print Network

Magic Tutorial #7: Netlists and Routing John Ousterhout Computer Science Division Electrical.) This tutorial corresponds to Magic version 6. Tutorials to read first: Magic Tutorial #1: Getting Started Magic Tutorial #2: Basic Painting and Selection Magic Tutorial #3: Advanced Painting (Wiring and Plowing) Magic

Martin, Alain

286

Women farmers in early twentieth century American fiction: Gates, Cather, Glasgow, Ferber, and Hurston  

Microsoft Academic Search

By comparing Eleanor Gate's The Plow-Woman (1906), Willa Cather's O Pioneers! (1913), Edna Ferber's So Big (1924), Ellen Glasgow's Barren Ground (1925), and Zora Neale Hurston's Their Eyes Were Watching God (1937) to urban novels of the period, I argue that while urban American novels emphasize internal, personal freedom of choice, the rural fictions emphasize both women's internal and external

Douglas William Werden

2001-01-01

287

Investigation of dry friction of submicrometer thick polyurethane films on a hard, smooth substrate  

Microsoft Academic Search

Our research on friction mechanisms has shown that the frictional force between sliding surfaces at moderate speeds and loads is primarily due to mechanical effects, such as plowing of surfaces by entrapped wear particles. In the absence of mechanical interactions, the coefficient of friction is extremely low. In this paper, one way of eliminating mechanical interactions is presented. Hard, smooth

M. Mosleh; N. P. Suh

1996-01-01

288

Soil Erosion and Agricultural Sustainability  

Microsoft Academic Search

Data drawn from a global compilation of studies support the long articulated contention that erosion rates from conventionally plowed agricultural fields greatly exceed rates of soil production, erosion under native vegetation, and long-term geological erosion. Whereas data compiled from around the world show that soil erosion under conventional agriculture exceeds both rates of soil production and geological erosion rates by

D. R. Montgomery

2009-01-01

289

Cultivation Intensity in Relation to Organic Matter and Related Properties in a Vertisol in Southern Turkey  

Microsoft Academic Search

As most of the organic carbon (C) in the biosphere resides in the soil in the form of soil organic matter (SOM), tillage practices can potentially increase C losses to the atmosphere as carbon dioxide, thus contributing to greenhouse gases that exacerbate climate change. In the past century, conventional tillage, involving plowing and secondary cultivation, has unwittingly decreased C stocks

John Ryan; Selim Kapur; Hayriye Ibrikci; Murari Singh

2011-01-01

290

Design and construction of an experimental mass spectrometer  

E-print Network

III. Analyzer Design Considerations . . .................. 15 IV. Source Design Considerations . . . .................. 27 V. Summary and Review of Design Considerations . . . . . 55 VI. Gas Plows and Vacuum Technique ...................... 59... Source ................ 41 7. Molecular Beam .................. ................. 52 8. Sample and Vacuum S y s t e m ..................... . . 6 1 9. Magnet Characteristics............................6.3 10. Magnet Performance...

Wall, Robert F.

2013-10-04

291

HortTips NewsletterVol. 2, No. 1 Welcome to our new newsletter for current issues in the landscape and garden. This newsletter is aimed  

E-print Network

from salt Cold injury to bamboo Cold damage to hellebore Winter injury on liriope Damage on mondo grass WINTER! Here is a gallery of casualties from the cold, snow, ice, salt, snow plows, hungry deer, voles, etc. Wait until new growth before pruning! Salt damage on Virginia pine Salt damage on white pine

Hill, Wendell T.

292

Iran's mammoth gas program to eliminate flaring by 1980  

Microsoft Academic Search

Today's Middle East reserves and production figures are impressive, but tomorrow's plans are staggering. Middle East countries are gearing up to halt gas flaring, recover NGL, expand reserves, enhance recovery, conserve energy, and industrialize. Just to capture associated gas now being flared will cost $25 billion, and that is only a start. Middle East oil producers are plowing enormous sums

1978-01-01

293

The Nestucca oil spill; A Christmas story  

Microsoft Academic Search

It was winter cold on the Pacific Ocean on December 22, 1988, when plowing through the seas came the tug Ocean Service towing the good barge Nestucca. All was well - for a time. Then, as the two came into Grays Harbor, Washington, the monotonous yet peaceful chuga-chuga-chuga of the tug was disturbed by the sudden parting of the heavy

Yaroch

1991-01-01

294

Debris transport around high-speed snowplows  

Microsoft Academic Search

The distribution of airborne debris around high-speed snowplows affects visibility and thus road safety. A combination of calculations, windtunnel experiments, and road trials are presented to provide knowledge of debris distributions and to obtain understanding of the mechanisms that can reduce suspended debris. Measurements obtained around windtunnel models show the influence of a variety of plow geometries on the location

Hany Kamel Nakhla

2001-01-01

295

40 CFR Appendix II to Subpart S of... - As-Received Testing Vehicle Rejection Criteria  

...CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty...has been used for severe duty (trailer towing for passenger cars, snow plowing, racing) 4. The vehicle has a...

2014-07-01

296

Challenges and Strategies Related to Hearing Loss among Dairy Farmers  

ERIC Educational Resources Information Center

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…

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

2005-01-01

297

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...

298

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

ERIC Educational Resources Information Center

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,…

Johnston, Mary

1990-01-01

299

Theme: Educational Trends.  

ERIC Educational Resources Information Center

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.…

Agricultural Education Magazine, 1998

1998-01-01

300

Impacts of Zone Tillage and Red Clover on Corn Performance and Soil Physical Quality  

Microsoft Academic Search

benefits of conservation tillage with the yield benefits of conventional moldboard plow tillage (e.g., Pierce et Despite extensive research, reduced corn (Zea mays L.) perfor- mance is still encountered using conservation tillage on fine-textured al., 1992) for cool humid climatic zones. Here, a narrow soils in cool humid temperate climates. These problems are intensified zone 10 to 20 cm wide

C. F. Drury; C. S. Tan; W. D. Reynolds; T. W. Welacky; S. E. Weaver; A. S. Hamill; T. J. Vyn

2003-01-01

301

Be prepared. Learn how to drive in winter conditions. Winter weather challenges our  

E-print Network

, and when blowing snow impairs visibility. Always drive with your headlights on. 8. Be extremely cautious to drive below the posted speed. No matter how much experience you have, the way your car will move on snow when approaching highway maintenance vehicles such as snow plows and salt or sand trucks. Maintain

Kavanagh, Karen L.

302

Sustainable Management of Dryland Alfisols (Red Soils) in South India  

Microsoft Academic Search

A community based cooperative research project was implemented on farmers' fields on some dryland Alfisols in Tamil Nadu, India, to demonstrate and validate improved dry-farming technologies, such as: 1) soil and water conservation and water harvesting; 2) cropping systems, including intercropping and double cropping; 3) recycling of processed agricultural wastes and byproducts; and 4) low-cost drip irrigation. Disc plowing to

S. P. Palaniappan; R. Balasubramanian; T. Ramesh; A. Chandrasekaran; K. G. Mani; M. Velayutham; R. Lal

2009-01-01

303

Environmental aspects of ethanol derived from no-tilled corn grain: nonrenewable energy consumption and greenhouse gas emissions  

Microsoft Academic Search

Nonrenewable energy consumption and greenhouse gas (GHG) emissions associated with ethanol (a liquid fuel) derived from corn grain produced in selected counties in Illinois, Indiana, Iowa, Michigan, Minnesota, Ohio, and Wisconsin are presented. Corn is cultivated under no-tillage practice (without plowing). The system boundaries include corn production, ethanol production, and the end use of ethanol as a fuel in a

Seungdo Kim; Bruce E. Dale

2005-01-01

304

Soil Quality Assessment after Weed-Control Tillage in a No-Till Wheat–Fallow Cropping System  

Microsoft Academic Search

retaining crop residue on the soil surface to reduce ero- sion create an environment favorable for downy brome Adoption of reduced-tillage fallow systems in the western USA is because tillage operations are shallow (or eliminated) limited by winter annual grass weeds such as downy brome (Bromus and downy brome seeds are not buried deep enough to tectorum L.). Moldboard plowing

T. A. Kettler; D. J. Lyon; J. W. Doran; W. L. Powers; W. W. Stroup

2000-01-01

305

RESISTENCIA AL DESGASTE DE CUCHILLAS DE ARADOS ROTATIVOS EN OPERACIÓN EN SUELOS TROPICALES  

Microsoft Academic Search

The wear resistance of blades of three types of rotary plows (rotavator, power harrows and motorhoes) in tropical soils of Santa Fe de Antioquia was studied. Also, rubber wheel-dry sand abrasive wear tets were performed in laboratory according to ASTM G65 standard. The maximum wear in field tests was found in blades from power harrows and rotavator. The high rotating

HUGO GONZÁLEZ; Ingeniero Agrícola; WILMER PÉREZ; MARIA LUISA ANAYA; CARLOS RESTREPO

2007-01-01

306

Math 55a: Honors Advanced Calculus and Linear Algebra Homework Assignment #3 (8 October 1999)  

E-print Network

definitions, one can easily fall into the habit of plowing ahead with the first approach that comes to mind error prone and easier on Travis to grade. To help you get in the habit of seeking such solutions, allowing centers of the ffl­neighborhoods to be in a larger ambient metric space does not change the notion

Elkies, Noam D.

307

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...

308

Influence of rate and placement of phosphate fertilizer on growth and yield of hard red spring wheat in diverse tillage systems  

Microsoft Academic Search

Management of P is a major issue for crop producers who grow hard red spring wheat (Triticum aestrivum, L.) with conservation tillage. Compared to the use of the moldboard plow, tillage that leaves crop residue on the soil surface can cause changes in soil chemical, biological, and physical properties. These changes may affect management practices for fertilizer P. Two studies

G. W. Rehm; A. L. Sims; J. A. Lamb

2003-01-01

309

The epiphytology of spearmint rust in Indiana  

Microsoft Academic Search

Summary Field studies indicated that subterranean aecia ofPuccinia menthaePers. are of little significance in the initiation of spearmint rust infection in undisturbed fields. Also, wild or escaped mints do not appear to be of significance. The primary source of inoculum comes either from fields that are not fall plowed or from infected rhizomes or transplants during spring planting. Temperatures during

William J. H. Stone; Ralph J. Green

1967-01-01

310

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

ERIC Educational Resources Information Center

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)

Barry, Tom

1979-01-01

311

Investigating X-ray emission from Pre-Planetary and Planetary Nebulae  

Microsoft Academic Search

The shaping of Pre-planetary nebulae (PPN) and Planetary Nebulae (PN) is believed to result from the interaction of a fast, collimated post-AGB wind plowing into the slow, dense wind emitted during the AGB phase, followed by an isotropic tenuous wind during the PN phase (Sahai and Trauger 1998). These interacting winds result in an expanding shell of shocked matter which

M. Stute; R. Sahai

2005-01-01

312

Rainfall in the Garden of the United States Great Plains, 1870–1889  

Microsoft Academic Search

The recent accumulation of all published precipitation records from 1870–1889 in the central and northern Great Plains of the United States provides a renewed potential in analyzing climatic reality during early settlement, corresponding to a time when some written histories documented that the ‘Rain followed the Plow’. Growing season precipitation in the central and northern Great Plains from 1870–1889 were

Cary J. Mock

2000-01-01

313

26. Photo copy of photograph, (original in Forest Service Office, ...  

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

26. Photo copy of photograph, (original in Forest Service Office, Elkins, WV), photographer unknown, ca. 1936. VIEW NORTHWEST, GARAGE (DEMOLISHED), NURSERY MANAGER'S GARAGE AND RESIDENCE, AND PACKING BUILDING, TRANSPLANT SHEDS AND PLOW IN FOREGROUND. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

314

Fundamental Scratch Behavior of Styrene-Acrylonitrile Random Copolymers  

E-print Network

Software ................................... 20 3.2 Model PP and PVC Systems ................................................................ 21 3.3 Scratch Testing and Analysis ............................................................... 22... of model PP and PVC. (Resolution = 300 dpi) ................................................................................ 24 3.2 Summary of critical load values for visibility and plowing for model PP and PVC...

Browning, Robert Lee

2011-10-21

315

Amazing Grazing.  

ERIC Educational Resources Information Center

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…

Peterson, Cris

316

A publication of the Airport Technical Assistance Program of the Center for Transportation Studies at the University of Minnesota Purchasing equipment for your airport can  

E-print Network

/DOT Aeronautics regional engineer and other resources such as the AirTAP Capital Improvement Program (CIP) Guide and future needs, research equipment types and manufacturers, get several price estimates, justify the need amount · the specifics of horsepower, torque, casting distance, plowing speeds, etc. In addition, no bids

Minnesota, University of

317

Tillage and soil carbon sequestration—What do we really know?  

Microsoft Academic Search

It is widely believed that soil disturbance by tillage was a primary cause of the historical loss of soil organic carbon (SOC) in North America, and that substantial SOC sequestration can be accomplished by changing from conventional plowing to less intensive methods known as conservation tillage. This is based on experiments where changes in carbon storage have been estimated through

John M. Baker; Tyson E. Ochsner; Rodney T. Venterea; Timothy J. Griffis

2007-01-01

318

Intercalation index with hydrazine, morphology and surface microtopography of kaolinitic clays in the tropical asian soils  

Microsoft Academic Search

Using kaolinitic clays separated from plow layer samples of paddy and upland soils in tropical Asia, their intercalation behavior with hydrazine was studied and their morphology and surface microtopography were observed by electron microscopy, in which a gold decoration technique was adopted.In the red members of the soils developed on weathered basic volcanic rocks and limestones under tropical monsoon climate

Tomoo Hattori; Koyo Yonebayashi; Kazutake Kyuma

1979-01-01

319

EFFECT OF DIFFERENT TILLAGE METHODS ON SOIL PHYSICAL PROPERTIES AND CROP YIELD OF MELON (Cucumis melo)  

Microsoft Academic Search

A two year field experiment was conducted to investigate the effect of different tillage methods on soil physical properties and crop yield of melon. Tillage treatments in the study were moldboard plow + two passes of disk harrow as conventional tillage (CT), two passes of disk harrow as reduced tillage (RT), one pass of disk harrow as minimum tillage (MT)

Majid Rashidi; Fereydoun Keshavarzpour

320

EFFECT OF DIFFERENT TILLAGE METHODS ON SOIL PHYSICAL PROPERTIES AND CROP YIELD OF WATERMELON (Citrullus Vulgaris)  

Microsoft Academic Search

A two year field experiment was conducted to investigate the effect of different tillage methods on soil physical properties and crop yield of watermelon. Tillage treatments in the study were moldboard plow + two passes of disk harrow as conventional tillage (CT), two passes of disk harrow as reduced tillage (RT), one pass of disk harrow as minimum tillage (MT)

Majid Rashidi; Fereydoun Keshavarzpour

321

Transactions of the ASAE Vol. 48(5): 2005 American Society of Agricultural Engineers ISSN 0001-2351 1  

E-print Network

interference, is a major yield-limiting factor. This is because soil compaction: (1) reduces soil pore size, (2. Since this method is point-to-point, researchers have experimented with on-the-fly alternatives that can and soil. Keywords. Plow pan, Precision tillage. oil compaction, caused by either natural causes or human

322

HABITAT USE BY SWAINSON'S HAWKS ON THEIR AUSTRAL WINTERING GROUNDS IN ARGENTINA  

Microsoft Academic Search

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 Swainsons' 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,

SONIA B. CANAVELLI; MARC J. BECHARD; BRIAN WOODBRIDGE; MICHAEL N. KOCHERT; JUAN J. MACEDA; E. ZACCAGNINI

323

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...

324

40 CFR 232.3 - Activities not requiring permits.  

Code of Federal Regulations, 2010 CFR

...it does not involve a discharge, it does not need a...modification that changes the character, scope, or size of...of drainage ditches. Discharge associated with siphons...natural water filtration capacities do not constitute plowing...will never involve a discharge of dredged or fill...

2010-07-01

325

33 CFR 323.4 - Discharges not requiring permits.  

Code of Federal Regulations, 2010 CFR

... (iv ) The discharges of dredged or...United States. Any discharge of dredged or fill...natural water filtration capacities do not constitute plowing...will never involve a discharge of dredged or fill...modification that changes the character, scope, or size...

2010-07-01

326

America's First Government Documentary Films as Teaching Tools.  

ERIC Educational Resources Information Center

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…

Hendrickson, Kenneth E.

1991-01-01

327

Evolutionary-inspired probabilistic search for enhancing sampling of local minima in the protein energy surface  

PubMed Central

Background Despite computational challenges, elucidating conformations that a protein system assumes under physiologic conditions for the purpose of biological activity is a central problem in computational structural biology. While these conformations are associated with low energies in the energy surface that underlies the protein conformational space, few existing conformational search algorithms focus on explicitly sampling low-energy local minima in the protein energy surface. Methods This work proposes a novel probabilistic search framework, PLOW, that explicitly samples low-energy local minima in the protein energy surface. The framework combines algorithmic ingredients from evolutionary computation and computational structural biology to effectively explore the subspace of local minima. A greedy local search maps a conformation sampled in conformational space to a nearby local minimum. A perturbation move jumps out of a local minimum to obtain a new starting conformation for the greedy local search. The process repeats in an iterative fashion, resulting in a trajectory-based exploration of the subspace of local minima. Results and conclusions The analysis of PLOW's performance shows that, by navigating only the subspace of local minima, PLOW is able to sample conformations near a protein's native structure, either more effectively or as well as state-of-the-art methods that focus on reproducing the native structure for a protein system. Analysis of the actual subspace of local minima shows that PLOW samples this subspace more effectively that a naive sampling approach. Additional theoretical analysis reveals that the perturbation function employed by PLOW is key to its ability to sample a diverse set of low-energy conformations. This analysis also suggests directions for further research and novel applications for the proposed framework. PMID:22759582

2012-01-01

328

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

NASA Astrophysics Data System (ADS)

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 after three years of experimenting with different tillage systems.

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

2007-07-01

329

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)

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 provided moisture conservation in the root zone is guaranteed. In this regard subsoiling is essential. Moreover, it is concluded that the time between subsoiling and planting is a key factor and should not exceed one week.

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

330

Determinants of breeding distributions of ducks  

USGS Publications Warehouse

The settling of breeding habitat by migratory waterfowl is a topic of both theoretical and practical interest. We use the results of surveys conducted annually during 1955-81 in major breeding areas to examine the factors that affect the distributions of 10 common North American duck species. Three patterns of settling are described: homing, opportunistic, and flexible. Homing is generally more pronounced among species that use more stable (more predictable) wetlands, such as the redhead (Aythya americana), canvasback (A. valisineria), lesser scaup (A. affinis), mallard (Anas platyrhynchos), gadwall (Anas strepera), and northern shoveler (Anas clypeata). Opportunistic settling is more prevalent among species that use less stable (less predictable) wetlands, such as northern pintail (Anas acuta) and blue-winged teal (Anas discors). Flexible settling is exhibited to various degrees by most species.The 10 species are shown to fall along a natural ordination reflecting different life history characteristics. Average values of indices of r- and K-selection indicated that pintail, mallard, blue-winged teal, and shoveler have the most features associated with unstable or unpredictable environments. Gadwall, American wigeon (Anas americana), and green-winged teal (Anas crecca) were intermediate, and attributes of the diving ducks were associated with the use of stable or predictable environments.Some species--notably mallard, gadwall, blue-winged teal, redhead, and canvasback--tend to fill available breeding habitat first in the central portions of their range, and secondly in peripheral areas. Other species--American wigeon, green-winged teal, northern shoveler, northern pintail, and lesser scaup--fill their habitat in the order it is encountered during spring migration.Age and sex classes within species vary in their settling pattern. Some of this variation can be predicted from the mating systems of ducks in which breeding females, especially successful ones, have a greater investment in habitat resources and are more likely to return to the same area in subsequent years.

Johnson, D. H.; Grier, J. W.

1988-01-01

331

Sources of variation in survival and breeding site fidelity in three species of European ducks  

USGS Publications Warehouse

1. We used long-term capture-recapture-recovery data and a modelling approach developed by Burnham (1993) to test a priori predictions about sources of variation in annual survival rates and fidelity within a population of individually marked females in three species of European ducks from a breeding ground study site in Latvia. 2. True annual survival was higher for diving ducks (tufted duck 0-72, common pochard 0-65) and lower for northern shoveler (0-52). Survival of female diving ducks was positively correlated with mean winter temperatures at Western European wintering areas, the relationship being much stronger for pochard. 3. We present the first unbiased estimates of breeding fidelity and permanent emigration in European ducks. Estimated fidelity rates were high (0'88-1-0) and emigration rates low (0-0-12) for all three species, and we found strong evidence for age-specific differences in fidelity of pochards. Unusual long-distance (up to 2500 km) breeding dispersal movements that we found in female tufted ducks have not been documented in any other European waterfowl and are most probably a result of saturated nesting habitats. 4. Fidelity was a function of patch reproductive success in the previous year for all three species providing support for the idea that patch success is an important cue influencing fidelity. 5. Fidelity probability increased to 1.0 for shovelers during the last 12 years of study following provision of critical improvements in nesting habitats and suggested that habitat conditions and reproductive success determined site fidelity and settling patterns for shoveler and probably also influenced fidelity of the two other species. In predictable habitats, fidelity is a parameter that reflects the integration of fitness components and is thus a good quantity for assessing the effectiveness of habitat management actions.

Blums, P.; Nichols, J.D.; Hines, J.E.

2002-01-01

332

Trace element concentrations in wintering waterfowl from the Great Salt Lake, Utah.  

PubMed

The Great Salt Lake (GSL) is an important region for millions of migratory waterbirds. However, high concentrations of some trace elements, including Hg and Se, have been detected within the GSL, and baseline ecotoxicological data are lacking for avian species in this system. We collected common goldeneye (Bucephala clangula), northern shoveler (Anas clypeata), and green-winged teal (A. crecca) from the GSL during the winters of 2004-2005 and 2005-2006 to evaluate sources of variation in liver trace element concentrations. Hg concentrations were among or exceeded the highest values reported in the published literature for common goldeneye, northern shoveler, and green-winged teal. Average Hg (total) concentrations of common goldeneye peaked in midwinter, whereas average Se concentrations peaked during late winter. During late winter, 100% and 88% of female goldeneye contained elevated concentrations of Hg [>or=1.0 microg/g wet weight (ww)] and Se (>or=3.0 microg/g ww), respectively, and 5% and 14% contained potentially harmful amounts of Hg (>or=30.0 microg/g ww) and Se (>10.0 microg/g ww), respectively. Similarly, 30% and 16% of male goldeneye contained potentially harmful concentrations of Hg and Se, respectively. Concentrations of Hg and Se were elevated in 100% and 79%, respectively, of northern shoveler samples (sexes combined) collected during February. We suggest that waterfowl contain biologically concerning amounts of Hg and Se during winter while on the GSL and further research is needed to evaluate the effect of these elements on GSL waterbirds. PMID:18560923

Vest, J L; Conover, M R; Perschon, C; Luft, J; Hall, J O

2009-02-01

333

Rainman: Renowned rainwater harvester Billy Kniffen may be retired, but he's not slowing down anytime soon  

E-print Network

18 tx H2O Summer 2011 Story by Leslie Lee One week a#31;er his o#23;cial retirement from the Texas AgriLife Extension Service on April #27;#24;, Billy Kni#28;en could be found crisscrossing the United States#30;bringing rainwater harvesting... education and systems to organizations in Arizona, North Texas, Kansas, and Georgia. ?I don?t know yet what retirement is,? Kni#28;en said. ?Last week was my #18;rst week of retirement, and I spent almost all of it shoveling, digging holes, and se#14...

Lee, Leslie

2011-01-01

334

Some Relationships Between Stripping Machinery Mass and Overburden Volumes  

E-print Network

for purposes herein is arbitrarily established, niiich, for cxa. . . &. le, consi" ts oi' the product of the no:. inal dipper si e on the siiovcl times function'l dumping reach. Tnis v lue io correlated;;. ith the oI&crating v, eight (net ?eight ?lus... on summary sheet of Appendix No. 1. The NUFs, maximum usefulness factor, as used here1n for a stripping shovel is defined as the product of the nominal size of the dipper 1n cub1c yards, and the dumping reach 1n feet schematically shown as r' in Fig, 5...

Rumfelt, Henry F.C

2012-06-07

335

The use of blood in Anas clypeata as an efficient and non-lethal method for the biomonitoring of mercury.  

PubMed

Hg was analyzed in seven tissues of 52 common shoveler Anas clypeata collected from the coast of SE Gulf of California. Mean Hg concentrations were highest in the liver (2,885 ng g?¹) and lowest in the gizzard (621 ng g?¹); they followed the order: liver, feathers > muscle tissue and tissues of the circulatory system > digestive organs. Hg levels were similar or higher than birds of the same trophic level and feeding habits. Considering the relationships of Hg among tissues and blood we recommend the use of blood as an efficient method to monitor Hg. PMID:23595347

Raygoza-Viera, J R; Ruiz-Fernández, A C; Ruelas-Inzunza, J; Páez-Osuna, F

2013-07-01

336

Some observations on the dentition of an isolated group in northeast Poland.  

PubMed

Clinical examination of the teeth and the mouth was carried out on a group of 133 "Old Believers," 54 males and 79 females, and a control group of 138 Poles living in the same area of Augostova in northeast Poland, 63 males and 75 females. Studying the frequency of Carabelli's cusp, shovel-shaped incisors, missing teeth, microdonita, supernumerary teeth, and torus palatinus in both groups, it was found that Carabelli's cusp and torus palatinus are more frequent among Poles. Such differences could be attributed to differences in ethnic origin of the two groups. PMID:1247107

El-Nofely, A

1976-01-01

337

What's next for hydraulic excavators. [Comparisons and developments in earthmoving equipment at surface mine sites  

SciTech Connect

This paper compares the use of hydraulic shovels to the more commonly used electric draglines in surface mining environments. It compares the historical reliability of the electric draglines to the yet to be proven reliability of the newer technology of the hydraulic excavator. The paper contrasts both the operating cost and service-life cost of each type of machine along with the performance advantages of both types of excavation equipment. Finally the paper discusses the improvements in the operation of hydraulic excavator as a result of electronic and computer-aided control systems.

Not Available

1993-06-01

338

An epizootic of avian botulism in a phosphate mine settling pond in northern Florida.  

PubMed

Type C botulism was determined to be the cause of an epizootic among waterfowl and shorebirds in a phosphate mine settling pond in northern Florida during May and June of 1979. Several hundred birds, the most common of which were American coots (Fulica americana), wood ducks (Aix sponsa), common gallinules (Gallinula chloropus), and northern shovelers (Anas clypeata), were afflicted over about a three-week period. A second smaller outbreak occurred in the same pond in early December of 1979. This is apparently the first time that botulism has been reported in waterbirds of Florida. PMID:6997514

Forrester, D J; Wenner, K C; White, F H; Greiner, E C; Marion, W R; Thul, J E; Berkhoff, G A

1980-07-01

339

Out of the sandbox - cohesive dragline planning  

SciTech Connect

Since 1983, Southern Illinois University Carbondale (SIUC), through the Coal Research Center in Carterville, Illinois, has been engaged in operator, engineer, supervisor and manager training in the foundations, plan formulation, iteration and improvement in efficiency of dragline planning and operations. 3d-Dig is a 3-D modeling package used in SIUC's training program to simulate digging and dumping from truck-shovel, dozer-push and dragline operations. SIUC has a scale model dragline and dragline simulator available to assist course attendees with standard dig progressions and optimizing operator technique. 1 fig., 6 photos.

Cobcroft, T. [Marston & Marston Inc., St Louis, MO (United States)

2008-01-15

340

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

SciTech Connect

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.

Yelick, Kathy

2012-01-01

341

Safe Chain Saw Operation.  

E-print Network

AND FELLING WEDGES I EXTI~bRJiSHER ~ ~ CHAIN FILING ~ ~ TOOLS FUEL CAN AND FUNNEL SHARP AX Figure 3. Use proper equipment to help you do the job safely. 2 /. SLEDGE HAMMER SHOVEL Special cautions: Electrically-powered chain saws re quire special...: ? Owner's manual in plastic bag ? Gasoline-oil fuel mixture stored in approved con tainer ? Chain oil ? Round file and guide for dressing (sharpening) chain ? Flat file and depth gauge to file the depth guides ? Wrenches to fit all nuts and lugs...

Nelson, Gary S.

1982-01-01

342

[In-situ remediation of polychlorinated biphenyls polluted soil by ecological controlling measures: a field trial].  

PubMed

A field experiment was conducted to study the remediation of agricultural soils polluted with polychlorinated biphenyls (PCBs) by several ecological controlling measures. After sequential stages of liming, plowing, planting alfalfa and paddy, a significant part of PCBs was removed from the soil, with an average removal rate of 86.9%. The treatment also decreased the toxic equivalency of dioxin-like PCBs in soil. Analysis of PCB congener composition showed that at stages of liming, plowing and alfalfa planting, the low-chlorinated biphenyls were removed; whereas at the stage of paddy planting, the high-chlorinated biphenyls were degraded. The ecological controlling measures had little influence on the microbial communities in soil. The results suggest that ecological control techniques could be widely applied in the remediation of agricultural soils with PCBs contamination. PMID:23002635

Pan, Cheng; Teng, Ying; Luo, Yong-Ming; Tu, Chen; Li, Xiu-Fen; Ma, Ting-Ting; Zhang, Man-Yun; Li, Zhen-Gao; Song, Jing

2012-07-01

343

Scattering of electromagnetic waves from a randomly perturbed quasiperiodic surface  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

344

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

USGS Publications Warehouse

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.

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

2003-01-01

345

Using a remote sensing field experiment to investigate flux-footprint relations and flux sampling distributions for tower and aircraft-based observations  

Microsoft Academic Search

During a remote sensing field experiment conducted in the Southern Great Plains in 1997 (SGP97), tower and aircraft-based flux observations were collected over one of the main study sites in central Oklahoma. This is an agricultural region and contains primarily grassland\\/pasture and winter wheat, which was recently harvested leaving a significant number of fields either as wheat stubble or plowed

William P. Kustas; Martha C. Anderson; Andrew N. French; Dean Vickers

2006-01-01

346

\\  

Microsoft Academic Search

Most U.S. farmers prepare their soil for seeding and weed and pest control through tillage—plowing operations that disturb the soil. Tillage practices affect soil carbon, water pollution, and farmers’ energy and pesticide use, and therefore data on tillage can be valuable for understanding the practice’s role in reaching climate and other environmental goals. In order to help policymakers and other

John K. Horowitz; Robert M. Ebel; Kohei Ueda

2010-01-01

347

Characterization of dents and grooves on polymer films using scanning white light interferometry  

Microsoft Academic Search

Surface deformation inflicted on two different kinds of thin layered polymer films was investigated under static indentation and dynamic loading (plowing) at room temperature. Affecting the surface were polished spherical steel tips of 0.5-1.6 mm radii moving at 0.1-16.0 mm\\/s along the surface. A load of 2-5 N was applied on the tip normal to the surface. The surface response

Ivan Kassamakov; Kari Ojala; Ari Salmi; Edward Hæggström; Juha Aaltonen; Arne Huber; Heimo Saarikko; Mathias Österberg; Markku Oinonen

2006-01-01

348

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

SciTech Connect

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.

Barbarick, K.A.; Ippolito, J.A.; Westfall, D.G. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Soil and Crop Sciences

1998-07-01

349

The effects of flow rate and pressure on breakthrough times and permeation rates through an impermeable membrane  

E-print Network

THE EFFECTS OF FLOW RATE AND PRESSURE ON BREAKTHROUGH TIMES AND PERMEATION RATES THROUGH AN IMPERMEABLE MEMBRANE A Thesis by PETER LEE GILMORE Submitted to the Graduate College of Texas AaM Univereity in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1986 Major subject: Industrial Hygiene THE EFFECTS OF PLOW RATE AND PRESSURE ON BREAKTHROUGH TIMES AND PERMEATION RATES THROUGH AN IMPERMEABLE MEMBRANE A Thesis by PETER LEE GILMORE Approved...

Gilmore, Peter Lee

2012-06-07

350

Keys to Profitable Onion Production in Texas.  

E-print Network

. For fall seeding it is important that previous crop residues from crops such as cotton or grain sorghum be shredded and plowed under to facilitate seeding. Heavy surface residues lower the effectiveness of chemical herbicides and interfere with uniform... for thrip control are listed in table 4. Always refer to specific use instructions and precautions on all pesticide containers before applying chemicals. Other pests. Soilborne insects such as wireworms and white grubs can cause serious damage to onions...

Longbrake, Tom; Hartz, Tim; Cotner, Sam; Roberts, Roland; Parsons, Jerry; Stockton, Austin; Cartwright, Bob; Amador, Jose

1987-01-01

351

DDT Persistence and Volatility as Affected by Management Practices after 23 Years  

Microsoft Academic Search

In 1971, an experiment was conducted in a field containing high amounts of residual DDT (dichlorodiphenyltrichloroethane) to evaluate deep plowing, followed by flooding, with and without organic matter applications, as soil and water management tools to reduce total DDT residues and preferentially degrade the residual DDT to DDD (l,l-dichloro-2,2-bis (p-chlorophenyl) ethane). The experimental site was revisited in 1994 to determine

W. F. Spencer; G. Singh; C. D. Taylor; R. A. LeMert; M. M. Cliath; W. J. Farmer

1996-01-01

352

Microbial Distributions And Their Potential Controlling Factors In Terrestrial Subsurface Environments  

Microsoft Academic Search

Terrestrial subsurface environments (below the plow layer) contain an enormous amount of the earth’s biomass, yet are relatively\\u000a undersampled compared to topsoil, aquatic, and marine environments. Depth emerges as a primary axis for relating distributions\\u000a of microorganisms and the factors controlling their distribution. There is generally a sharp drop in microbial biomass, diversity,\\u000a and activity as organic-rich topsoils deepen to

R. Michael Lehman

353

Waiting for Water  

ERIC Educational Resources Information Center

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…

Lamson-Nussbaum, Jorie

2013-01-01

354

Changing Supply of Grains in Texas.  

E-print Network

to pro- duction in the area. The area also has favorable weather conditions, growing season (rice requires 110 to 180 days of high temperatures) and good surface drainage. Favorable economic factors are its locatio~~ . near Gulf shipping points... of wheat is not recom- mended in the state. - plows, made possible the handling of large acre ages. Low cost of production by these method; gave wheat an economic advantage over other \\ crops. Therefore, commercial production oi wheat for the cash...

Moore, Clarence A.; Whitney, Howard S.

1959-01-01

355

Utility concepts applied to the socio-economic subregionization analysis  

E-print Network

of Every Variable By Basic Variable in Every Group (1"actor) Sorting Subroutine Set the Range of Smoothed . lonbasic Variable From 0 To 1 Calculate the Lumped Values of Every Subject of Every Group (Factor) Figure 1. Plow Chart of iiesearch 1...'rocedur". Sort ing Subroutine Reset the Values of Lumped Variables From 0 To 1 Determine the Factor Score of the Lumped Variables Cluster Analysis of the Final Factor Scores Stop Figure ] . Flow Chart of Research Procedure (Continued...

Hsieh, Joseph Ching-Huei

2012-06-07

356

Managing erosion and water quality in agricultural watersheds by small detention ponds  

Microsoft Academic Search

Terrace-contouring systems with on-site water detention cannot be installed in areas of complex topography, small parceling and multi-blade moldboard plow use. However, field borders at the downslope end may be raised at the deepest part where runoff overtops to create detention ponds, which can be drained by subsurface tile outlets and act similar to terrace-contouring systems. Four of such detention

P. Fiener; K. Auerswald; S. Weigand

2005-01-01

357

Restoration of riparian habitat using experimental flooding  

Microsoft Academic Search

We evaluated treatments designed to remove saltcedar (Tamarix ramosissima) monocultures from riparian habitats using root plows (mechanical treatment) and aerial applications of the herbicide imazapyr\\u000a (chemical treatment) within twelve 4-ha impoundments in the Middle Rio Grande Valley in central New Mexico, USA. Following\\u000a these treatments, impoundments were flooded and water levels were reduced to stimulate native species re-establishment from\\u000a seed.

Matthew D. Sprenger; Loren M. Smith; John P. Taylor

2002-01-01

358

Fertilizer Experiments with Cotton.  

E-print Network

in the cotton-belt states, usually do not contain large amounts of organic matter, because the high temperatures and favorable moisture conditions lead to the rapid decomposition of the organic matter. Under these conditions, the processes of decay... only, the cowpeas receiving the residual effects of the fertilizer. The cowpeas have been harvested for seed and the vines plowed under for soil improvement. The average annual rainfall at Nacogdoehes during the 19 years, 1913 to 1931, inclusive...

Reynolds, E. B. (Elbert Brunner)

1932-01-01

359

Commercial Fertilizers and Their Use  

E-print Network

- sary, but other conditions are equally necessary. Organic matter is needed by all soils. It has a favorable physical action on the soil, and in other respects adds to its productiveness. The addition of manure, or the use of green crops plowed under... action, however, is very slow, even when used in connec? tion with organic matter, and it has practically IIo effect the first year. Phosphate rock is usually prepared for fertilizing purposes by treat? ing it wdth sulphuric acid. Phosphate rock...

Fraps, G. S.

1914-01-01

360

Changes in the Status of Harvested Rice Fields in the Sacramento Valley, California: Implications for Wintering Waterfowl  

Microsoft Academic Search

Harvested rice fields provide critical foraging habitat for wintering waterfowl in North America, but their value depends\\u000a upon post-harvest treatments. We visited harvested ricefields in the Sacramento Valley, California, during the winters of\\u000a 2007 and 2008 (recent period) and recorded their observed status as harvested (standing or mechanically modified stubble),\\u000a burned, plowed, or flooded. We compared these data with those

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

2010-01-01

361

Texas Persimmon Distribution and Control with Individual Plant Treatments.  

E-print Network

Texas uersimmon is a hard-to-kill wood! Extent of the Problem.. ...... Control with Sprays .............. Control with Pelleted Herbicides 9 . ..................... ...................... 3CUSSION XRATURE CITED ............... ng ~;uth Texas... such as chaining and root plowing. I sentially resistant to conventional herbicides a been applica&n 'of 12 to 16 pounds of 2, 4, 5 100 gallons of diesel oil as a basal spray in the I 1 considered a minor component of range &ge 1 as broadcast suravs. The most...

Scifres, C. J.

1975-01-01

362

Horses--Haulers, Racers, and Healers  

ERIC Educational Resources Information Center

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…

McIntosh, Phyllis

2014-01-01

363

Groundwater quality and crop-yield responses to tillage management on a Sparta sand  

Microsoft Academic Search

Groundwater beneath sandy soils in the Lower Wisconsin River Valley has more detections and larger concentrations of atrazine and nitrate–nitrogen (NO3–N) than groundwater beneath other areas of sandy soils with similar genesis in Wisconsin, USA. A 2.8-ha field study initiated in 1989 compared water quality and production potential of no-tillage (NT) and moldboard-plow tillage (MB) for corn (Zea mays L.)

B. Lowery; R. C. Hartwig; D. E. Stoltenberg; K. J. Fermanich; K. McSweeney

1998-01-01

364

Post-collision magmatism and tectonics in northwest Anatolia  

Microsoft Academic Search

A suite of biotite-hornblende granodiorite intrusions has been emplaced into blueschist-facies metasediments in northwest Anatolia, following collision between two continental margins, now represented by the Tavsanli and Sakarya zones. The 40Ar\\/39Ar ages of phengites and glaucophanes from the blueschists, metamorphosed under unusually high P-low T conditions (P=20±2 kbar, T=430±30° C), suggest that metamorphism apparently occurred over a period spanning at

Nigel B. W. Harris; Simon Kelley; Aral I. Okay

1994-01-01

365

Conservation tillage for carbon sequestration  

Microsoft Academic Search

World soils represent the largest terrestrial pool of organic carbon (C), about 1550 Pg compared with about 700 Pg in the\\u000a atmosphere and 600 Pg in land biota. Agricultural activities (e.g., deforestation, burning, plowing, intensive grazing) contribute\\u000a considerably to the atmospheric pool. Expansion of agriculture may have contributed substantially to the atmospheric carbon\\u000a pool. However, the exact magnitude of carbon

R. Lal; J. M. Kimble

1997-01-01

366

The intensification of pre-industrial cereal agriculture in the tropics: Boserup, cultivation lengthening, and the Classic Maya  

Microsoft Academic Search

Through a review of recent research in tropical ecology, soils science, and agronomy, this paper develops a model of tropical agricultural intensification through cultivation lengthening that applies to non-industrial cereal production in moist-to-wet tropical lowlands under conditions of high population density. Contrary to the predictions of many archaeological models, in tropical agricultural societies lacking plows, draft animals, or chemical fertilizers,

Kevin J. Johnston

2003-01-01

367

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)

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.

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

2012-12-01

368

Effects of land use on surface-water quality in the East Everglades, Dade County, Florida  

USGS Publications Warehouse

Water-quality characteristics were determined at five developed areas in the East Everglades, Dade County, Florida, during the 1978 wet season (June through October). These areas are designated as: Coopertown; Chekika Hammock State Park; residential area; rock-plowed tomato field; and Cracker Jack Slough agricultural area. Data from the developed areas were compared with data from four baseline sites in undeveloped areas to determine the effects of land use on the surface-water quality. The rock-plowed tomato field was the only area where surface-water quality was affected. Water quality at this field is affected by agricultural activities and chemical applications as indicated by increased concentrations of orthophosphate, organic nitrogen, organic carbon, copper, manganese, mercury, and potassium. The remaining four areas of land use had water-quality characteristics typical of baseline sites in nearby Northeast Shark River Slough or Taylor Slough. Chemical analyses of soil indicated chlorinated-hydrocarbon insecticide residues at Coopertown and the two agricultural areas, Cracker Jack Slough and the rock-plowed tomato field. Trace elements in concentrations greater than base level occurred at both agricultural areas (manganese), Chekika Hammock State Park (manganese), and at Coopertown (lead and zinc). (USGS)

Waller, Bradley G.

1982-01-01

369

An improved whole cell pertussis vaccine with reduced content of endotoxin  

PubMed Central

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

Dias, Waldely Oliveira; van der Ark, Arno A.J.; Sakauchi, Maria Aparecida; Kubrusly, Flavia Saldanha; Prestes, Ana Fabiola 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

370

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

NASA Astrophysics Data System (ADS)

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.

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

2009-09-01

371

The design of a noble VCSEL with DOE  

NASA Astrophysics Data System (ADS)

A brand-new approach in developing VCSEL lense is presented in this paper. Using the laser process or yellow light lithography process, we can merge semiconductor laser and diffraction optics elements (DOE) to become a single semiconductor optoelectronic device. To match the surface topology of the DOE with the structure of semiconductor laser, the DOE is carved on the SiO II layer of the vertical-cavity surface-emitting laser (VCSEL). The chiseled optoelectronic semiconductor element becomes as a DOE-VCSEL device, it has the DOE function to control the emission distribution of the emitting laser.

Liang, Tsair-Chun; Chang, Sheng-Hsiung; Huang, Hsi-Shan

2007-09-01

372

Bulletin of Tibetology: Volume 7 Number 3 : Full issue  

E-print Network

in my "FOUNDATION OF TIBET AN MYSTICISM". (IUder, London) 1l small acuminated circle or blue dot (bindu) and appears in three­ dimensional form as a multi-coloured flaming jewel, i.e., a small sphere from which a flame emerges. If we put all... in making offerings to it. From there Fa-hien and his party crossed the Indus. • 'In former times men had chiselled paths along the rocks and distributed ladders on the face of them, to the number altogether of 700, at the bottom of which there was a...

Namgyal Institute of Tibetology

1970-11-20

373

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

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

374

Mx gene diversity and influenza association among five wild dabbling duck species (Anas spp.) in Alaska  

PubMed Central

Mx (myxovirus-resistant) proteins are induced by interferon and inhibit viral replication as part of the innate immune response to viral infection in many vertebrates. Influenza A virus appears to be especially susceptible to Mx antiviral effects. We characterized exon 13 and the 3’ UTR of the Mx gene in wild ducks, the natural reservoir of influenza virus and explored its potential relevance to influenza infection. We observed a wide range of intra- and interspecies variation. Total nucleotide diversity per site was 0.0014, 0.0027, 0.0044, 0.0051, and 0.0061 in mallards, northern shovelers, northern pintails, American wigeon, and American green-winged teals, respectively. There were 61 haplotypes present across all five species and four were shared among species. Additionally, we observed a significant association between Mx haplotype and influenza infection status in northern shovelers. However, we found no evidence of balancing or diversifying selection in this region of the Mx gene. Characterization of the duck Mx gene is an important step in understanding how the gene may affect disease resistance or susceptibility in wild populations. Furthermore, given that waterfowl act as a natural reservoir for influenza virus, the Mx gene could be an important determinant in the ecology of the virus. PMID:20621205

Dillon, Danielle; Runstadler, Jonathan

2010-01-01

375

Grinding energy and mechanisms for ceramics  

NASA Astrophysics Data System (ADS)

A technological basis for efficient ceramic machining requires a fundamental understanding of the prevailing grinding mechanisms. Most past research on grinding mechanisms for ceramics has followed either the "indentation fracture mechanics" approach or the "machining" approach. The indentation fracture mechanics approach likens abrasive workpiece interactions to idealized small-scale indentations. The machining approach typically involves measurement of cutting forces together with microscopic observations of grinding debris and surfaces produced. Both approaches provide important insights into the grinding mechanisms for ceramic materials. However, up to now, no physical model has been presented which can quantitatively account for the energy associated with grinding of ceramics. The present research was undertaken to investigate grinding mechanisms for ceramics and to account for the energy expended. SEM observations of grinding debris for various ceramics and a glass over a wide range of conditions indicate material removal mainly by brittle fracture associated with lateral cracking and crushing. However, the ground surfaces reveal extensive ductile flow with characteristic scratches along the grinding direction and smearing. Ductile flow typically extends to a depth of 1-5 mum below the ground surface. For silicon nitride, etching with hydrofluoric acid removed the smeared layer, which would indicate that it consists of a glassy phase probably formed by oxidation at elevated grinding temperatures. Although material removal appears to occur mainly by brittle fracture, most of the grinding energy is apparently associated with ductile flow. An order of magnitude analysis indicates that the energy expended by brittle fracture constitutes a negligible portion of the total grinding energy. An upper bound plowing analysis is presented which can account the specific energy in terms of the geometry of the plowed groove. A new model has been developed which relates the grinding power to the rate of plowed surface area generated by the diamond cutting points on the wheel surface interacting with the workpiece. Over a wide range of grinding conditions, the power increases approximately proportionally with the rate of surface area generated, which suggests a nearly constant energy per unit area of plowed surface. Values obtained for energy per area for plowing are much bigger than the corresponding fracture surface energies, which further indicates that most of the grinding energy is associated with ductile flow.

Hwang, Tae Wook

376

Measurement of coal-cutting forces underground with the in-seam tester. Report of investigations/1986  

SciTech Connect

The Bureau of Mines designed, fabricated, and is using an in-seam tester for in-situ determination of coal-cutting forces. The report describes the results of field tests conducted in the Pocahontas No. 3 and Upper Freeport seams to obtain peak and mean cutting forces during coal cutting with several bit geometries, including radial and point attack bits currently used on drum-type machines. Comparisons were also made between new and worn bits, and by using data obtained from a Bureau-modified chisel bit. The test results show that longwall plough cutting (horizontal cuts) in bony coal bands (shale) requires greater than three times the cutting force for the same cuts in a vertical direction. When no bony coal is present, the cutting forces required to make horizontal and vertical cuts are equal. Worn bits require four to five times more cutting and normal force than new or undamaged bits. Normal force increased drastically for the worn chisel bit. Peak force encountered in making independent cuts was found to be approximately three times higher than that required to make interactive cuts using a spacing-to-depth-of-cut ratio of 2. Both rake and clearance angles were found to have a significant effect on normal and cutting force.

Sundae, L.S.

1986-01-01

377

Tool-related injuries among amateur and professional woodworkers.  

PubMed

Although woodworking is a popular hobby and the woodworking industry employs thousands of workers nationwide, few studies have examined injuries associated with this activity, especially in relation to woodshop tool use. We conducted a survey of amateur and professional woodworkers (n = 283) in New Mexico to determine histories and rates of tool-specific injuries. Injuries associated with woodshop tool use were reported by 64% of all respondents. Hammers, chisels/gouges, and table saws were most frequently reported in association with injuries, although the highest tool-specific injury rates were associated with use of jointer-planers (4.9 injuries per 1000 person-hours of use), chisels/ gouges (3.3 injuries), and drill presses (3.1 injuries). One third reported tool use-associated injuries that were severe enough to require professional medical attention; 5% of all respondents suffered partial amputations. Courses in the safe use of shop tools may help to reduce rates of injuries among woodworkers. PMID:8899580

Becker, T M; Trinkaus, K M; Buckley, D I

1996-10-01

378

[A paratibial fasciotomy technic in chronic venous insufficiency].  

PubMed

From extensive paratibial fasciectomies on account of crural ulcers W. Hach changed to subcutaneous fasciotomy from an incision 30 to 40 mm long with digital severing of the perforating veins. Its main effect is the creation of wide communication between the subfascial and suprafascial space. The subcutaneous tissue affected with lipodermatosclerosis rest on muscles well supplied with blood which can improve the trophics of surface tissues. The reduction of the surgical approach to 10 mm calls for special instruments. Instruments designed by the author proved useful. The author operated eight patients with advanced varicosis of the saphena maior with incompetence of two to three Cockett veins and with developed lipodermatosclerosis. After stripping of the saphena maior the smaller varicosities were extracted by dented strippers, haemostasis was ensured by tamponade by means of an applicator. Cockett's veins were interrupted in the subfascial layer from a paratibial incision in the middle of the leg by means of a 10 mm L-shaped chisel and straight chisel. This was followed by prolongation of fasciotomy by means of a fasciotome to the inner ankle. The postoperative course was devoid of complications with minimal pain, the cosmetic effect was excellent. PMID:8768957

Horný, J

1996-01-01

379

Age-class separation of blue-winged ducks  

USGS Publications Warehouse

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 and flyway differences in remigial measurements and reduced performance of age classification models as evidence of high variability in size of blue-winged ducks' remiges. Variability in remigial size of these and other small-bodied waterfowl may be related to nutrition during molt.

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

1995-01-01

380

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

NASA Astrophysics Data System (ADS)

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 soil respiration were stronger in the first year, with compost soils experiencing a 21 ± 1 % greater cumulative loss at SFREC and 16 ± 3 % more at Nicasio. The second year showed a similar trend, but with a lower magnitude loss. Aboveground NPP responded positively to compost additions and negatively to plowing at both sites. At SFREC, we measured 58 % more ANPP in composted relative to control plots in year one (369 vs 230 g C/m2) and 56 % more in year two (327 vs 209 g C/m2). Aboveground NPP on plowed plots was 129 g C/m2 in year one, and 185 g C/m2 in year two. Plowed soils also showed a significant decline in soil C and N concentrations (C= 2.67 ± 0.13%, N = 0.20 ± 0.01%). Compost additions increased soil C and N concentrations (C= 3.92 ± 0.29%, N = 0.32 ± 0.02%) relative to control soils (C= 3.52 ± 0.20%, N = 0.27 ± 0.07%). Throughout the experiment, we did not detect significant treatment differences in CH4 or N2O fluxes, nor did we detect significant differences at any individual sampling point. These results suggest that compost addition can lead to an increase in ecosystem C storage, with a small offset from elevated soil respiration.

Ryals, R.; Silver, W. L.

2010-12-01

381

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

NASA Astrophysics Data System (ADS)

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?

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

2014-05-01

382

Cross-site soil microbial communities under tillage regimes: fungistasis and microbial biomarkers.  

PubMed

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 18:2?6). 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

Sipilä, Timo P; Yrjälä, Kim; Alakukku, Laura; Palojärvi, Ansa

2012-12-01

383

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

PubMed Central

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

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

2014-01-01

384

Passages  

E-print Network

the path of fantasy, and always being there as advisor, editor, shoulder-to-cry-on, fellow dreamer, and above a11- -friend. Thanks for "Carol's paragrap h" and all the rest. 0) that I were as great As is my grief, or lesser than my name, Or that I... life paled at the icy touch of death. His glance fell on Spock, and he knew that the cold fingers of that same terrible fear had touched the Vu1can--for a moment, his face was totally naked, furrows of pain plowed into it with brutal clarity...

James, Susan K.

1978-01-01

385

Cropping management using color and color infrared aerial photographs  

NASA Technical Reports Server (NTRS)

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.

Morgan, K. M.; Morris-Jones, D. R.; Lee, G. B.; Kiefer, R. W.

1979-01-01

386

Prediction of soil loss with the CREAMS model  

SciTech Connect

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.

Becker, N.M.

1984-07-24

387

Applications of ERTS-1 data to landscape change in eastern Tennessee  

NASA Technical Reports Server (NTRS)

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.

Rehder, J. B. (principal investigator)

1973-01-01

388

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)

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.

Miyoshi, K.; Buckley, D. H.

1978-01-01

389

A study of the deep water benthos of the northwestern Gulf of Mexico  

E-print Network

for the net on ~ths first cruise using this dredge, and the net often became tangled in the plow share teeth. As a result a light aluminum frame wae installed to hold it in place. Ths "bottom" and "top" of this were covered ~th hardware cloth to protect..., and are there- fore not available for the radula examinations so necessary for proper species diagnoses. In light of these opinions, this author submits these descriptions of the turrids with the reservations that a future revision of this group and/or more...

Rowe, Gilbert T

2012-06-07

390

Alfalfa Root Rot.  

E-print Network

thought due to the pre- sence of an "alkali" in the soil, but its continued growth on the same land, showing widening circles of disease with each succeeding year, mould indicate at once a fungus trouble. Mr. W. H. Farley, whose lettera we select... shov that fungus must attack the healthy plants for some time before there are any visible signs ofdisease and for an area much larger than the small circle seemingly affected-or that the disease is not at all checked by plowing. As a matter of fact...

Curtis, Geo. W.

1892-01-01

391

Control and Management of Mesquite on Rangeland.  

E-print Network

, considering cost production-return, should extend over at least 20 years. Mesquite is capable of reestablishing itself from seed for at least I 0 to 40 years even if no new SPRAYING IN FRILL 4 STINGER DOZING seed is produced on the area. An example... fast range re covery is necessary at the time of mechanical opera tions which destroy native grass turf. Generally, SPRAYING ON TRUNK lASE / ROOT PLOWING heavy weed growth will follow such mechanical op erations unless seeded forage species...

Hoffman, Garlyn O.

1981-01-01

392

Momentum and heat fluxes in a turbulent air flow over a wet, smooth boundary  

E-print Network

l i b r a r y } A & M COLLEGE OF TEXAS ; MOMENTUM AND HEAT FLUXES IN A TURBULENT AIR PLOW OVER A WET, SMOOTH BOUNDARY A Dissertation By Warren Rice Submitted to the Graduate School of the Agricultural and Mechanical College of Texas... of ? with. ? =^- for runs 4 and 5 . . . .................. -60 Figure 34- Variation of with -H r for runs 6, 7 and 8 C c. .................. 61 Figure 35 Variation of ?jrb with -^L- for runs 9 and 10 . . . . . . f ......... 61 Figure 36 Variation...

Rice, Warren

2013-10-04

393

Forage Crops.  

E-print Network

ton per acre), and the secondgabout the same. After cutting it twice it matured a good crop of seed. Planted April 11; germinated . April 16. First blooms were noticed about June 1. It was from eighteen inches to two feet high June 15, when I cut it... walking plow running five inches deep, and afterwards harrowed with a steel harrow; harrowed again on March S. After the light rain on August 6, I planted alfalfa (August 9) ; germinated about the 13th to a perfect stand. Land was in a good pulverized...

1901-01-01

394

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

NASA Astrophysics Data System (ADS)

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.

Baker, Jennifer

395

Mortality of waterfowl on a hypersaline wetland as a result of salt encrustation.  

PubMed

Approximately 300 geese, primarily lesser Canada geese (Branta canadensis parvipes) were found unable to fly or dead on a small hypersaline lake (conductivity 77,000-90,000 mumhos/cm) in western Saskatchewan in September 1985. The birds were heavily encrusted with sodium sulfate crystals. Dead birds that were necropsied had aspirated lake water and had evidence of acute muscle degeneration. The live geese (155) were captured and moved to nearby freshwater wetlands where most apparently survived. Some birds died of severe myopathy after translocation. Five northern shovelers (Anas clypeata) were found encrusted with salt and unable to fly on the lake approximately 10 days later. Salt encrustation apparently occurred when rapid cooling of the lake resulted in supersaturation and crystallization of the dissolved salt. A local resident recalled similar events occurring on the lake in autumn on at least two other occasions during the past 50 yr. PMID:3820414

Wobeser, G; Howard, J

1987-01-01

396

Foot preferences during resting in wildfowl and waders.  

PubMed

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

Randler, Christoph

2007-03-01

397

Mortality of waterfowl on a hypersaline wetland as a result of salt encrustation  

SciTech Connect

Approximately 300 geese, primarily lesser Canada geese (Branta canadensis parvipes) were found unable to fly or dead on a small hypersaline lake (conductivity 77,000-90,000 mumhos/cm) in western Saskatchewan in September 1985. The birds were heavily encrusted with sodium sulfate crystals. Dead birds that were necropsied had aspirated lake water and had evidence of acute muscle degeneration. The live geese (155) were captured and moved to nearby freshwater wetlands where most apparently survived. Some birds died of severe myopathy after translocation. Five northern shovelers (Anas clypeata) were found encrusted with salt and unable to fly on the lake approximately 10 days later. Salt encrustation apparently occurred when rapid cooling of the lake resulted in supersaturation and crystallization of the dissolved salt. A local resident recalled similar events occurring on the lake in autumn on at least two other occasions during the past 50 yr.

Wobeser, G.; Howard, J.

1987-01-01

398

Candidate sample acquisition systems for the Rosetta  

NASA Technical Reports Server (NTRS)

The Comet Nucleus Sample Return (CNSR) mission, one of the four cornerstones of the ESA scientific program, is one of the most complex space ventures within the next century, both from technological and deep space exploration point of view. In the Rosetta scenario the sample acquisition phase represents the most critical point for the global mission's success. The proposed paper illustrates the main results obtained in the context of the CNSR-SAS ongoing activity. The main areas covered are related to: (1) sample properties characterization (comet soil model, physical/chemical properties, reference material for testing); (2) concepts identification for coring, shovelling, harpooning and anchoring; (3) preferred concept (trade off among concepts, identification of the preferred configuration); and (4) proposed development activity for gaining the necessary confidence before finalizing the CNSR mission. Particular emphasis will be given to the robotic and flexibility aspects of the identified sample acquisition systems (SAS) configuration, intended as a means for the overall system performance enhancement.

Magnani, P. G.; Gerli, C.; Colombina, G.; Vielmo, P.

1989-01-01

399

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

SciTech Connect

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.

Kline, H.M. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Andreychek, T.P.; Beeson, B.K. (Martin Marietta Corp., Baltimore, MD (United States). Aero and Naval Systems)

1993-01-01

400

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

SciTech Connect

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.

Kline, H.M. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Andreychek, T.P.; Beeson, B.K. [Martin Marietta Corp., Baltimore, MD (United States). Aero and Naval Systems

1993-04-01

401

Epizootiological features of avian cholera on the north coast of California.  

PubMed

An avian cholera (Pasteurella multocida) epizootic was observed among wildfowl at the Centerville Gun Club, Humboldt County, California (USA) in January 1978. Compared to their live populations and use of the area, coots (Fulica americana) died in proportionately greater numbers than any other species. Coots collected by gunshot were evaluated for sex and age composition, and morphometry from November 1977 through mid-January 1978 at this site. There was no substantial difference in the sex, age or morphometry between birds dying of avian cholera and from those dying from gunshot. Assuming coots dying of gunshot are representative of the general population, it appears there was little selection among coots by P. multocida. There was evidence for a sequential mortality similar to that reported previously at this site: coots were the first birds to die, followed by American wigeon (Anas americana) and northern pintails (A. acuta acuta); northern shovelers (A. clypeata) and mallards (A. platyrhynchos) died late in the epizootic. PMID:2716104

Mensik, J G; Botzler, R G

1989-04-01

402

Correlations of daily activity with avian cholera mortality among wildfowl.  

PubMed

We tested the hypothesis that wildfowl activities can influence the risk of avian cholera (Pasteurella multocida infection) for susceptible birds at Centerville, Humboldt County, California (USA). Avian cholera mortality characteristics from past epizootics were correlated with variations in flock size, habitat use and 11 feeding and nonfeeding behaviors among six empirically defined groups of wildfowl: American coots (Fulica americana), tundra swans (Cygnus columbianus), American wigeon (Anas americana), northern pintails (A. acuta), northern shovelers (A. clypeata)/mallards (A. platyrhynchos), and teal (A. discors, A. crecca, A. cyanoptera). The position of these wildfowl groups in past mortality sequences was directly correlated with mean flock size, time spent on land, and time spent grazing on land or in shallow water. We propose that variations in bird density, habitat use and frequency of grazing may serve as predisposing factors to avian cholera among wildfowl. PMID:1758019

Combs, S M; Botzler, R G

1991-10-01

403

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

USGS Publications Warehouse

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.

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

1991-01-01

404

Selection of operating machinery parameters for a bucket excavator  

SciTech Connect

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.

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

1985-05-01

405

Waterfowl density on agricultural fields managed to retain water in winter  

USGS Publications Warehouse

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).

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

1999-01-01

406

Avian influenza in wild waterfowl and shorebirds in the Donana National Park: Serological survey using the enzyme-linked immunosorbent assay.  

PubMed

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

Astorga, R J; Leon, L; Cubero, M J; Arenas, A; Maldonado, A; Tarradas, M C; Perea, A

1994-06-01

407

KSC-03PD-0578  

NASA Technical Reports Server (NTRS)

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.

2003-01-01

408

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

PubMed Central

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

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

2012-01-01

409

Geographical gradients in the population dynamics of North American prairie ducks.  

PubMed

1. Geographic gradients in population dynamics may occur because of spatial variation in resources that affect the deterministic components of the dynamics (i.e. carrying capacity, the specific growth rate at small densities or the strength of density regulation) or because of spatial variation in the effects of environmental stochasticity. To evaluate these, we used a hierarchical Bayesian approach to estimate parameters characterizing deterministic components and stochastic influences on population dynamics of eight species of ducks (mallard, northern pintail, blue-winged teal, gadwall, northern shoveler, American wigeon, canvasback and redhead (Anas platyrhynchos, A. acuta, A. discors, A. strepera, A. clypeata, A. americana, Aythya valisineria and Ay. americana, respectively) breeding in the North American prairies, and then tested whether these parameters varied latitudinally. 2. We also examined the influence of temporal variation in the availability of wetlands, spring temperature and winter precipitation on population dynamics to determine whether geographical gradients in population dynamics were related to large-scale variation in environmental effects. Population variability, as measured by the variance of the population fluctuations around the carrying capacity K, decreased with latitude for all species except canvasback. This decrease in population variability was caused by a combination of latitudinal gradients in the strength of density dependence, carrying capacity and process variance, for which details varied by species. 3. The effects of environmental covariates on population dynamics also varied latitudinally, particularly for mallard, northern pintail and northern shoveler. However, the proportion of the process variance explained by environmental covariates, with the exception of mallard, tended to be small. 4. Thus, geographical gradients in population dynamics of prairie ducks resulted from latitudinal gradients in both deterministic and stochastic components, and were likely influenced by spatial differences in the distribution of wetland types and shapes, agricultural practices and dispersal processes. 5. These results suggest that future management of these species could be improved by implementing harvest models that account explicitly for spatial variation in density effects and environmental stochasticity on population abundance. PMID:18631261

Saether, Bernt-Erik; Lillegård, Magnar; Grøtan, Vidar; Drever, Mark C; Engen, Steinar; Nudds, Thomas D; Podruzny, Kevin M

2008-09-01

410

Healey motorsports` amazing {open_quotes}1 valve{close_quotes} racing Healey  

SciTech Connect

Recently, the 22 foot, chisel shaped, electric racing vehicle {open_quotes}Powertron/QuickCable Spirit of San Antonio I{close_quotes} set a new world speed record in the class-3 under 1500 pound electric vehicle class. Lloyd Healey, the designer, builder, and driver of the streamlined electric car; set the record at the Bonneville Salt flats with an averaged speed of 129.354 mph. The car was built with a Cr-Mo frame, aluminum outer skin, and a handmade fiberglass nose piece. The car is capable of carrying twenty-four Type-31 truck lead acid batteries or thirty Type-34 car batteries. The car is powered by an 11 inch General Electric DC series wound motor that produces both high torque and horsepower. The racing team hopes to break the 200-mph mark, with some unofficial times already set above 150-mph.

NONE

1995-02-01

411

J.Toriwaki: Virtual sculpting and virtual woodblock printing by model-driven scheme  

E-print Network

Abstract. In this paper, we present an interactive design system based on virtual sculpting to create 3D solid objects, with the stress on the aspect of a tool to enjoy creation or manipulation of 3D shapes. In the virtual sculpting system, a user can form a solid object as if carving a workpiece with chisels. A 3D object generated by the system looks like a real wooden sculpture. If using a board as a workpiece, a user can generate a virtual printing woodblock. A user can synthesize a woodblock print from the virtual woodblock mentioned above, a virtual paper sheet, and a printing brush. In this system, the operations of sculpting and printing are similar to the real ones, and still even children can experience creation of complete computer graphics. 1.

S. Mizuno; M. Okada; J. Toriwaki

412

[A cosmetic surgery technique for varices in the lower extremities].  

PubMed

The author describes a variant of a cosmetic operation of varicosities of the lower extremities which proved successful in the course of 17 years. The operation was performed in a total of 1823 patients. Minimalization of the size and number of surgical incisions is made possible by the use of very simple instruments comprising an elevator of the saphena magna, strippers for subsidiary varicosities (4 sizes), an applicator of temporary tamponade and two types of chisels for suprafascial and subfascial severing of perforating veins. The number of operations on account of relapses is 9.04% during a representative period in 1990 and 1991. The period of work incapacity is by one week shorter. The cosmetic results are excellent. The instruments and the described technique are at present used in 35 institutes. PMID:8211390

Horný, J

1993-02-01

413

Modified pre-curved patellar basket plate, reconstruction of the proper length and position of the patellar ligament--a biomechanical analysis.  

PubMed

Biomechanical properties of basket plate fixation for fracture dislocation in the distal part of the patella were studied on 22 fresh-frozen lower extremities (human cadaveric knees). The patella and the patellar ligament with the proximal tibia were removed. A comminuted fracture of the distal part of the patella was created with a chisel. The fractured patella, patellar ligament and tibial tuberosity of each specimen were fixed with a basket plate and mounted into the jaws of the testing machine. The measured load to failure was 421.66+/-45.90 N, which is approximately 70% higher than the results in other studies. The results of the measurements verified the results of finite element analysis. The modified precurved patellar basket plate developed in this study showed improved performance compared to the pre-existing fixation methods. PMID:17433694

Krkovic, M; Bombac, D; Balazic, M; Kosel, F; Hribernik, M; Senekovic, V; Brojan, M

2007-06-01

414

Saltbush leaves: excision of hypersaline tissue by a kangaroo rat.  

PubMed

Dipodomys microps climbs into shrubs and harvests leaves of the halophyte Atriplex confertifolia throughout the year. The epidermal vesicles of these leaves are high in electrolyte concentration, but the specialized photosynthetic parenchyma which is arranged concentrically about the vascular bundles is low in electrolytes and high in starch. The lower incisors of D. microps are broad, flattened anteriorly, and chisel-shaped (unlike those of other kangaroo rats, which are rounded and awl-shaped) and are used to shave off the hypersaline, peripheral tissue of the leaves so that the inner tissue can be eaten. This atypical feeding behavior should minimize the reliance of D. microps on the unpredictable seed crops of desert annuals, and also favor its coexistence with other species of Dipodomys, which are primarily granivorous. PMID:17741983

Kenagy, G J

1972-12-01

415

Verification of radiocesium decontamination from farmlands by plants in Fukushima.  

PubMed

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 ¹³?Cs and ¹³?Cs were 22-179 and 29-225 Bq kg dry weight?¹, respectively. The ¹³?Cs and ¹³?Cs 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 ¹³?Cs and ¹³?Cs 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

Kobayashi, Daisuke; Okouchi, Toshiyasu; Yamagami, Mutsumi; Shinano, Takuro

2014-01-01

416

Effects of "open burning" on the greenhouse gas exchange from a single-rice paddy field in Japan  

NASA Astrophysics Data System (ADS)

Paddy fields are artificially maintained wetland and are one of the large source of CH4. Besides, a large quantity of N2O is emitted from the soil surface due to the decomposition of inorganic fertilizer. A long term continuous measurement of GHG fluxes between atmosphere and paddy ecosystem is effective method to clarify the contribution of paddy fields to recent rapid increase of GHG concentration. In this study, three techniques for flux measurement (eddy covariance, aerodynamic gradient, and chamber techniques) were applied to investigate the annual variation of three GHG (CO2, CH4 and N2O) exchanges at a single-rice paddy field for two years. An observational site is located on reclaimed land in the southern part of Okayama Prefecture, Japan. In addition, an experimental paddy field was divided into two areas to investigate what impact is brought on the annual GHG fluxes 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 Nov. 29th, 2011, and residue was not burned and directly plowed into soil at the other area as usual. We illustrate some results for the control term before the burning experiment, and for the comparison term after the experiment.

Kawamoto, Y.; Akaike, Y.; Kunishio, A.; Murakami, H.; Ono, K.; Hayashi, K.; Iwata, T.

2012-12-01

417

In vitro investigation of skin damage due to microscale shearing.  

PubMed

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

Jee, Taekwon; Komvopoulos, Kyriakos

2014-11-01

418

The Ecology of Wrath  

E-print Network

ouses were shut tight, and cloth wedged around “Hdoors and windows, but the dust came in so thinly that it could not be seen in the air, and it settled like pollen on the chairs and tables, on the dishes, ” wrote John Steinbeck in The Grapes of Wrath. The same year, 1939, the author elaborated in a letter that his goal in writing the book was “to rip a reader’s nerves to rags ” by laying bare the life of the Dust Bowl migrants with whom he had spent time. Oklahoma Congressman Lyle Boren called the book “an infernal creation of a twisted distorted mind.” After Congress passed the Homestead Act in 1862, thousands of settlers moved to the semi-arid grasslands of the North American plains to farm and graze cattle. They plowed the fields and planted dryland wheat. High demand generated the promise of economic development and brought in more powerful plows, further expanding arable land. The grasses receded, leaving the ground exposed and vulnerable. When the drought came in 1930, strong winds whipping across the plains created severe dust storms, which continued for nearly a decade, moving millions of tons of topsoil and wiping out farms and ranches across 19 states in the heartland, which became known as the Dust Bowl. “And then the dispossessed were drawn west–from

Polyxeni Potter

419

The Effect of surface morphology on the friction of Electrogalvanized sheet steel in forming processes  

SciTech Connect

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.

Skarpelos, P.N. [Lawrence Berkeley Lab., CA (United States)]|[California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering

1993-12-01

420

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)

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.

Rehder, J. B. (principal investigator)

1973-01-01

421

Bird use of agricultural fields under reduced and conventional tillage in the Texas Panhandle  

USGS Publications Warehouse

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.

Flickinger, E.L.; Pendleton, G.W.

1994-01-01

422

Residue Removal Affects the Carbon Content of No-Till Soils  

NASA Astrophysics Data System (ADS)

No-till crop management often results in increased soil organic carbon contents. However, the effect of residue removal for fuel or animal fodder on soil carbon content is not well understood, especially with no-till management practices. We utilized a multiyear study at six locations in central Mexico, with a wide range of soil and climatic conditions to determine the effect of varying rates of residue removal and no-till management on soil carbon content. Treatments consisted of annual moldboard plowing and no-till management practices with 100%, 67%, 33% and none of the corn (Zea mays) crop residue retained on the no-till soil surface. Even when all crop residues were removed, no-till practices maintained carbon levels above that of moldboard plowing at five of the six locations. Retaining crop residues affected the soil carbon content differently depending on climatic conditions. Retaining crop residues on the soil surface increased soil carbon content at a much faster rate in cool conditions than in warm tropical conditions. Carbon content was greater in regions with higher amounts of rainfall than in drier regions. Retaining crop residues on the soil surface with no-till will usually increase soil carbon content, but climatic conditions should be considered to determine if crop residue would be more effectively utilized for energy production or animal fodder.

Potter, K. N.; Torbert, H. A.

2003-12-01

423

[Functions of different cultivation modes in oasis agriculture on soil wind erosion control and soil moisture conservation].  

PubMed

During 2001-2002, the effects of different cultivation modes including winter irrigation and zero tillage, crop-grass intercropping, and early spring film mulching on sand entrainment, wind velocity gradient and soil moisture conservation were studied in the middle reaches of the Heihe River in the Hexi Corridor region. The results showed that all these modes could reduce soil wind erosion and halt sand entrainment to different degrees. Compared with the bare fields exposed by spring plowing, early spring film mulching could increase soil moisture storage by 35.6%. At present, spring plowing and sowing was a main factor responsible to the occurrence of sand storms and the increase in suspended dust content. Farmlands in the upper and middle reaches of the Heihe River generally produced a dust transport up to 4.8-6.0 million tons per year, which was higher than that of sandy desert in the same region. In the Hexi Corridor region, the suspended dust amount produced from 1 hm2 farmland was equivalent to that of 1.5 hm2 desert. PMID:15669480

Su, Peixi; Zhao, Aifen; Du, Mingwu

2004-09-01

424

The use of alkalinity as a conservative tracer in a study of near-surface hydrologic change in tropical karst  

NASA Astrophysics Data System (ADS)

Water shortages commonly increase in frequency following forest clearance on lands overlying karst in the tropics. The mechanism underlying this hydrologic change is likely to depend on the land use which follows forest cover. To determine the flow paths which prevail for a progression of land uses common to the uplands of Leyte, Philippines, samples of interflow were collected during the rainy season and titrated to determine their alkalinities. The ratio of the measured alkalinity to the value predicted by equilibrium calculations for each sample was used as an indication of the contact time of the water with the limestone. The responses of the alkalinity saturation ratio and the runoff depth to increasing rainfall depth were used to substantiate the hypothesis that epikarst infilling and changing soil structure create throttles to percolation and infiltration. The forest site was found to generate interflow primarily as pipe flow, with the infiltration and percolation throttles rarely exceeded. Similarly, infiltration was not limiting for the slash/mulch site; however, the level of soil disturbance was adequate to initiate a throttle at the epikarst which increased the volume of interflow generated. The total percolation was similar for the plowed and slash/mulch sites; however, the interflow was decreased at the plowed site by reduced infiltration at the soil surface. The throttles to surface infiltration and epikarst percolation were even greater at the pasture sites, resulting in high runoff generation. However, comparatively greater infiltration was observed in the pasture having contour-hedgerows.

Chandler, David G.; Bisogni, James J.

1999-03-01

425

Modeling the effect of soil structure on water flow and isoproturon dynamics in an agricultural field receiving repeated urban waste compost application.  

PubMed

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 (?), non-compacted soil with visible macroporosity (?), 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 properties were optimized on one calibration year (2007/08) using pressure head, water content and lysimeter outflow data, and then tested on the whole 2004/2010 period. Lysimeter outflow and water content dynamics in the soil profile were correctly described for the whole period (model efficiency coefficient: 0.99) after some correction of LAI estimates for wheat (2005/06) and barley (2006/07). Using laboratory-measured degradation rates and assuming degradation only in the liquid phase caused large overestimation of simulated isoproturon losses in lysimeter outflow. A proper order of magnitude of isoproturon losses was obtained after considering that degradation occurred in solid (sorbed) phase at a rate 75% of that in liquid phase. Isoproturon concentrations were found to be highly sensitive to degradation rates. Neither the laboratory-measured isoproturon fate parameters nor the independently-derived soil hydraulic parameters could describe the actual multiannual field dynamics of water and isoproturon without calibration. However, once calibrated on a limited period of time (9 months), HYDRUS-2D was able to simulate the whole 6-year time series with good accuracy. PMID:24958010

Filipovi?, Vilim; Coquet, Yves; Pot, Valérie; Houot, Sabine; Benoit, Pierre

2014-11-15

426

Bacteria-to-Archaea ratio depending on soil depth and agrogenic impact  

NASA Astrophysics Data System (ADS)

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 carbon content and the amount of soil metabolically active Bacteria and Archaea cells revealed that distribution of both Bacteria and Archaea throughout the soil profile was governed by organic matter content. Thus, the organic matter content seemed to be the main factor of declining Bacteria-to- Archaea ratio down the profile (from 7.1 to 4.2 for virgin soil and from 5 to 3.9 for arable soil). In conclusion, Archaea out-compete Bacteria under conditions of reduced energy supply.

Semenov, Mikhail; Manucharova, Natalia; Kuzyakov, Yakov

2014-05-01

427

Individual quality, survival variation and patterns of phenotypic selection on body condition and timing of nesting in birds.  

PubMed

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 nest initiation date and body condition covary with both reproductive and survival components of fitness. These associations lead to a positive covariance of these two fitness components within individuals and to the conclusion that these two traits are indeed correlates of individual quality. PMID:15657762

Blums, Peter; Nichols, James D; Hines, James E; Lindberg, Mark S; Mednis, Aivars

2005-04-01

428

Dental morphology of early Holocene foragers of North India: non-metric trait frequencies and biological affinities.  

PubMed

The biological affinities of semi-nomadic, early to mid-Holocene foragers of the mid-Ganga Plain, North India are undetermined, yet understanding their place in the population history of South Asia is important. Non-metric tooth trait frequencies are reported for three broadly contemporary, bio-culturally similar, and geographically proximate samples, collectively known as Mesolithic Lake Culture (MLC). The Arizona State University - Dental Anthropology System was used to score 43 tooth-trait combinations (23 maxillary; 21 mandibular). Non-metric trait frequencies are used to determine biological affinities of MLC to a global sample of living populations and to prehistoric and living groups of South Asia. The MLC dental pattern includes lightly sculpted upper incisors in which labial curvature, lingual shoveling, and tuberculum dentale exhibit low grades of expression and low-moderate frequencies. First molars have full-sized hypocones with slight reduction in M2 and M3. Accessory cusps are infrequent and small. Mandibular teeth are morphologically simple and retain conservative attributes. Incisors and canines exhibit weak shoveling. Molar accessory cusps are infrequent, though C-6 attains moderate grades in M3. The molar series (M1:M2:M3) has an Y:X:X groove pattern and 5:4:4 cusp number. Upper M3 agenesis (5%) is less common than lower M3 agenesis (10.0%). Smith's Mean Measure of Divergence (MMD) and Ward's minimum variance cluster methods are used to assess inter-group bio-distance in global and regional South Asian settings. In the global comparison, multi-dimensionally scaled MMD values reveal three groups: African, Asian, and a third group composed of MLC, prehistoric South Asians, and European samples. Within South Asia, MMD and cluster analysis find MLC's closest affinities to the Chenchu, a living tribal group of Andhra Pradesh. This result contradicts earlier assertions based on osteological assessment that descendants of Mesolithic foragers of North India (MLC) cannot be identified in the Indian subcontinent. The next closest affinity is with Chalcolithic and Neolithic groups of Pakistan and with a late Chalcolithic group (INM) of west central India. As knowledge of the dental morphology of living and prehistoric South Asians increases, the population history of the subcontinent and its role in understanding world-wide patterns of migration will be clarified. PMID:24050393

Lukacs, John R; Pal, J N

2013-12-01

429

Limitations of using a thermal imager for snow pit temperatures  

NASA Astrophysics Data System (ADS)

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 atmospheric temperatures are enhanced. At crusts or other heterogeneities, we were unable to create a sufficiently homogenous snow pit surface and non-internal gradients appeared at the exposed surface. The immediate adjustment of snow pit temperature as it reacts with the atmosphere complicates the capture of the internal thermal structure of a snowpack even with thermal videos. Instead, the shown structural dependency of the IR signal may be used to detect structural changes of snow caused by kinetic metamorphism. The IR signal can also be used to measure near surface temperatures in a homogenous new snow layer.

Schirmer, M.; Jamieson, B.

2013-10-01

430

Limitations of using a thermal imager for snow pit temperatures  

NASA Astrophysics Data System (ADS)

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 heterogeneities, we were unable to create a sufficiently planar snow pit surface and non-internal gradients appeared at the exposed surface. The immediate adjustment of snow pit temperature as it reacts with the atmosphere complicates the capture of the internal thermal structure of a snowpack with thermal videos. Instead, the shown structural dependency of the IR signal may be used to detect structural changes of snow caused by kinetic metamorphism. The IR signal can also be used to measure near surface temperatures in a homogenous new snow layer.

Schirmer, M.; Jamieson, B.

2014-03-01

431

Effect of the long-term application of different fertilization systems on soddy-podzolic soils  

NASA Astrophysics Data System (ADS)

The characteristics of the control variant of an acid nonlimed soil in which the pH values have remained stable for 40 years should be used as criteria for the maximum permissible loads of mineral fertilizers affecting the agrochemical and biological soil properties. Considerable alteration of these limiting agrochemical and biological soil properties (in the variant with NK application) leads to the soil degradation not only in the plow layer but also in the 1-m-deep layer. The application of lime, especially in combination with complete mineral fertilizer, prevents soil degradation, improves its properties, decreases the uptake of heavy metals by plants, and favors the production of ecologically clean agricultural products.

Gomonova, N. F.; Skvortsova, I. N.; Zenova, G. M.

2007-04-01

432

An Unremembered Diversity: Mixed Husbandry and the American Grasslands  

PubMed Central

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

SYLVESTER, KENNETH; CUNFER, GEOFF

2009-01-01

433

Control of Structure in Conventional Friction Stir Welds through a Kinematic Theory of Metal Flow  

NASA Technical Reports Server (NTRS)

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.

Rubisoff, H.A.; Schneider, J.A.; Nunes, A.C.

2009-01-01

434

Microstructure and Wear Resistance of Laser Clad Fe-Cr3C2 Composite Coating on 35CrMo Steel  

NASA Astrophysics Data System (ADS)

Fe-Cr3C2 hard coatings with varying Cr3C2 content were produced on 35CrMo steel substrates by laser cladding. The experimental results showed that the coatings were uniform, continuous, and free of cracks. High adhesions between all produced coatings and their corresponding substrates were obtained due to the metallurgical interfaces between them. The microstructures of the coatings were mainly composed of austenitic dendrites and M7C3. The microhardness gradually increased from the bottom to the top of the coating, and increased with elevation of Cr3C2 content. The Fe-Cr3C2 coatings improved the sliding wear resistance of the 35CrMo steel substrates obviously, and the dominant wear mechanism was spalling fatigue, with plowed grooves on the worn surfaces.

Han, Bin; Li, Meiyan; Wang, Yong

2013-12-01

435

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

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.

Adair, J.H.; Mecholsky, J.J., Jr.; Mitchell, D.J.

1999-01-25

436

Long-term measurements of CH{sub 4} and N{sub 2}O fluxes in the Colorado short grass steppe  

SciTech Connect

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.

Mosier, A.R.; Delgado, J.A. [USDA/Agricultural Research Service, Ft. Collins, CO (United States); Valentine, D.W. [Colorado State Univ., Ft. Collins, CO (United States)] [and others

1995-06-01

437

Method for transporting low temperature heat long distances  

SciTech Connect

A new method for transporting low temperature heat long distances consists of a system of high pressure air with a high specific heat in a low heat loss and low cost non-metallic heat pipe that is coilable for plowing into the earth. The hot air is used for space heating or for heating hot water heating systems or for process heat. The purpose of the invention is to reduce cost and save fossil fuel. High pressure air as opposed to hot water or steam for moving heat energy ecologically sound. Heat from remote geothermal hot water wells can be economically moved several miles or hundreds of miles to communities for space heating. Heat from remote waste heat sources at electrical generating plants and other fossil fuel burning heat system can be transported long distances for building use.

Pugh, P.F.

1983-10-11

438

An Augmented Lagrangian Method for Sliding Contact of Soft Tissue  

PubMed Central

Despite the importance of sliding contact in diarthrodial joints, only a limited number of studies have addressed this type of problem, with the result that mechanical behavior of articular cartilage in daily life remains poorly understood. In this paper, a finite element formulation is developed for the sliding contact of biphasic soft tissues. The Augmented Lagrangian method is used to enforce the continuity of contact traction and fluid pressure across the contact interface. The resulting method is implemented in the commercial software COMSOL Multiphysics. The accuracy of the new implementation is verified using an example problem of sliding contact between a rigid, impermeable indenter and a cartilage layer for which analytical solutions have been obtained. The new implementation’s capability to handle a complex loading regime is verified by modeling plowing tests of the temporomandibular joint (TMJ) disc. PMID:22938363

Guo, Hongqiang; Nickel, Jeffrey C.; Iwasaki, Laura R.; Spilker, Robert L.

2012-01-01

439

Dry Sliding Wear Characteristics of Gravity Die-Cast Magnesium Alloys  

NASA Astrophysics Data System (ADS)

The paper deals with the wear behavior of conventional cast Mg-Sn-based alloys. The alloys were studied through pin- on- disk wear test under four different loading conditions; namely, 9.8, 19.6, 29.4, and 39.2 N. The study highlights the cumulative wear loss, volumetric wear loss, dry sliding wear rate, and coefficient of friction of the alloys. The volumetric wear increased with increasing applied load. The wear mechanism was studied with scanning electron microscope. The wear occurs mainly by plowing mechanism and also by delamination. During wear, extensive plastic deformation and work hardening occurred. Microstructural analysis has been carried out for all the alloys at different loading conditions.

Poddar, Palash; Das, Arpan; Sahoo, K. L.

2014-04-01

440

Effect of current on multiple pinches of Xe plasma in capillary discharge  

NASA Astrophysics Data System (ADS)

The effect of the current on the pinching process of Xe plasma columns pumped by capillary discharge has been studied theoretically and experimentally. An extreme ultraviolet emission monitor (E-Mon, 13.5 nm in 2% bandwidth) was applied to record the temporal evolution of the 13.5 nm (2% bandwidth) emission. According to real current waveforms, the pinching processes were simulated with the snow-plow model. Both the experimental and the simulation results showed that intensity of the 13.5 nm emission reached the maximum when the plasma was pinched to the minimum radius. The E-Mon signals and the simulations indicated that under different amplitudes of the currents the plasma could be pinched more times and faster with higher discharge current.

Xu, Qiang; Zhao, Yongpeng; Xie, Yao; Liu, Yang; Li, Qi; Wang, Qi

2014-03-01

441

EVLA Constraints on the Progenitors of Supernovae Type Ia  

NASA Astrophysics Data System (ADS)

While Type Ia supernovae are used increasingly as cosmological probes to trace the expansion history of the Universe, the nature of their progenitors remains enshrouded in mystery. In the favored model for these explosions, a white dwarf accretes material from a hydrogen-rich donor star (e.g. red giant). A necessary implication of this model is the production of weak radio emission as the SN blastwave plows through the wind of the donor star. Previous radio searches for this signal have been unsuccessful, largely attributed to the fact that the expected emission lay just beyond the VLA sensitivity. Here we present recent results from our EVLA program, which utilizes the increased sensitivity to search for the expected signal from SNe Ia. The non-detection of radio emission with the EVLA would indicate double-degenerate progenitor systems (binary white dwarf) or require serious modifications to the single-degenerate model.

Chomiuk, Laura; Soderberg, A. M.; Chevalier, R.; Badenes, C.; Fransson, C.

2011-01-01

442

Modeling the CME Ejecta and Coronal Wave of the 2012-06-14 Event Using STEREO and SOHO Observations  

NASA Astrophysics Data System (ADS)

Coronal mass ejections (CMEs) play a crucial role in disrupting the space environment as they plow through the heliosphere after being expelled from the Sun. In particular, energetic CMEs in the corona consist of at least two elements: the classic CME ejecta or driver visible as a discrete, bright blob of erupting coronal material; and an enveloping compressive wave that forms deep in the corona due to the sudden plasma motion associated with the erupting ejecta. Using STEREO/COR2 and SOHO/LASCO coronagraph observations, we separately characterize the ejecta and surrounding coronal wave for the CME observed on 2012-06-14. These results are subsequently cast into a new form of input conditions for an Enlil MHD simulation. We discuss the model results obtained from the coronagraph observations, as well as the Enlil simulation of this event.

de Koning, C. A.; Odstrcil, D.; Pizzo, V. J.

2012-12-01

443

Groundstate OH masers associated with Herbig-Haro objects  

NASA Astrophysics Data System (ADS)

Jets from newly-formed stars plow into the surrounding ISM, creating nebulous regions known as Herbig-Haro (HH) objects. Signatures of C-type shocks have been found in many HH objects. Models of shock-excited 1720-MHz OH masers associated with SNRs suggest that the masers could be signposts of C-type shocks. We have conducted a 1720MHz survey towards a number of HH objects to see if any shock-excited masers occur in association with these objects. Some results of our search are reported. When present, the 1720-MHz OH line can occur as emission, absorption or as P Cygni profiles. OH mainline emission is found in many of our sources. We have identified several potential 1720-, 1665- and 1667-MHz OH masers.

de Witt, A.; Smits, D. P.

2007-03-01

444

Fast Method to Determine CMEs properties at 1 AU and Propositions for an Automated Detection of CME Fronts  

NASA Astrophysics Data System (ADS)

Coronal mass ejections (CMEs), when directed towards Earth, are the primary driver for space weather. It is therefore important to predict their arrival time at Earth, as well as their speed and other characteristics. We propose a snow-plow analytical model that we apply to some CMEs using 3-D steady-state solar wind driven by magnetic field observations. The results are compared with other from existing methods and in situ observations, giving good estimation of CMEs arrival time to 1AU. We also present different image processing methods and preliminary results for automated detection of CMEs front and shape. These preliminary results are compared to data were the intervention of human judgment played a mayor role.

Hernandez Charpak, J.; Lugaz, N.; Perez Romanello, C.; Hernandez Hoyos, M.; Roussev, I. I.

2010-12-01

445

Chondrule Formation: Nebular Gas Confinement of Impact Splashes  

NASA Astrophysics Data System (ADS)

We show that the impact debris from a high-speed collision between two planetesimals during the first few million years would sweep up the nebular gas as a snow plow, leading to deceleration and compression of the debris into a thin shell. This shell breaks up into dense bullets through the Rayleigh-Taylor instability. As a result of the compression by the gas, these bullets will have super-Roche densities and thus will gravitationally collapse to form new planetesimals. Chondrules that may have formed from impact melting would thus rapidly be reaccreted into planetesimals. These dense environments are ideal for forming compound chondrules. The hydrodynamic interaction with the nebular gas could lead to mixing between the newly formed chondrules and surviving pre-impact material. Volatiles can be exchanged between these components in the dense bullets, allowing for chemical complementarity. We believe that this scenario may have some advantages over earlier impact scenarios for chondrule formation.

Dullemond, Cornelis Petrus; Johansen, Anders

2013-07-01

446

Sunyaev-Zeldovich Effect observations of sub-structure in galaxy clusters  

NASA Astrophysics Data System (ADS)

We propose to observe the 'bullet' cluster of galaxies - 1E 0657-56 - which consists of two sub-clusters in the process of merging and manifests relatively cold clouds plowing through hot intra-cluster gas, using the ATCA in H75 and H168 arrays at 7 and 12 mm. We aim to image the sub-structure in the gas pressure distribution via the inverse-Compton scattering of cosmic microwave background photons (the Sunyaev-Zeldovich Effect; SZE). Additionally, we anticipate detection, for the first time ever, of polarized SZE from anisotropic electron distribution in consequence of the enhancement of cluster magnetic fields as they drape the cold fronts. The observations constitute a probe of fine structure in the physical state of the intra-cluster gas, the physics of propagation and stability of cold fronts in cluster mergers and a measure of cluster magnetic field.

Subrahmanyan, Ravi; Wieringa, Mark; Narasimha, D.; Malu, Siddharth

2009-04-01

447

Monitoring the Tidal Disruption of a Gas Cloud Approaching Sgr A*  

NASA Astrophysics Data System (ADS)

Gillessen et al.'s exciting discovery of a 3 earth-mass cloud of gas and dust that is approaching SgrA* on a nearly radial orbit presents a rare opportunity to watch the processes of tidal disruption and feeding of a SMBH in unprecedented detail. Analytical arguments and simulations indicate that the cloud will be compressed, fragmented and shock heated by RT and KH instabilities as it plows through the hot accretion flow of this ultra-sub-Eddington accreting black hole. The strength of the X-ray emission during pericenter passage will depend critically on the radial density and temperature profiles of the hot accretion flow, presenting an unique probe of these properties. The amount of X-ray emission will also be a powerful discriminator of proposed scenarios for the origin of the cloud.

Baganoff, Frederick

2012-09-01

448

How Well Do We Understand Collisionless Shocks?  

NASA Astrophysics Data System (ADS)

Collisionless shocks arise in the solar wind when fast streams overtake slowly, when ICMEs plow through the pre-existing solar wind plasma, and in front of every planet visited to date. In the inner solar system, where stream interactions first form shocks, the shocks are weak. So too, are bow shocks that occur when the interplanetary field is strong or bowshocks that are observed far down the flanks. These shocks are laminar and are well understood. The stronger shocks associated with stream-interactions in the outer heliosphere, in front of fast ICMEs, and at most bow shocks seen close to the planet are less well understood. In this review, we examine both our areas of confidence and those areas in which more work is necessary.

Russell, Christopher

449

Ground-water quality near a sewage-sludge recycling site and a landfill near Denver, Colorado  

USGS Publications Warehouse

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)

Robson, Stanley G.

1977-01-01

450

Application of magnetic tracer method for quantification of pedoturbations in soils under different land use  

NASA Astrophysics Data System (ADS)

Pedoturbations are widely known and good classified by scientists. It is known 10 types of pedoturbations, allocated by F.D. Hole (1961) and supplemented by D.L. Johnson and collaborators (1987). They influence on many soil properties and also on migration substances (including pollutants). But there is a lack of data of quantitative assessments of pedoturbations especially in soils under different land use. In this paper are shown approaches for the use of magnetic tracer method for assessments of pedoturbation processes. This method is widely spread for study lateral solid phase soil matter (soil erosion), but first use for study pedoturbations. Magnetic tracer method is based on study of spherical magnetic particles (SMP) in soils. Origin of SMP is mainly connected with atmospheric deposition of fly ash, resulting from coal burning in steam engines of locomotives and thermal electric power stations. The period of active emission of SMP is the last 150 years. Magnetic spherules are stable and resistant to soil weathering and can be preserved in soils for decades without any clear signs of destruction. In European part of Russia and Middle West USA were analyzed 63 soil profiles under virgin forest and steppe vegetation and croplands. Vertical distribution of SMP in the upper 30 cm divided into 5 types: a) residually accumulative, b) not uniform with maximum in the upper 10 cm, c) not uniform with maximum in the 10-20 cm, d) not uniform with maximum in the 20-30 cm, e) gomogeneous. Vertical distribution of SMP reflects intensity of pedoturbations, because SMP migrate into the soils only from the atmospheric depositions. Labeled types of SMP vertical distribution are listed in order of increasing intensity of the pedoturbation. Most intensive pedoturbations are detected in arable soils. Depending on the region arable soils characterized by highest percentage of soil profiles with homogenous type of SMP distribution (up to 17%) and lowest percentage of soil profiles 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%.

Zhidkin, Andrey; Gennadiyev, Alexander

2014-05-01

451

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)

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.

Miyoshi, K.; Buckley, D. H.

1979-01-01

452

Hydrologic modeling to screen potential environmental management methods for malaria vector control in Niger  

NASA Astrophysics Data System (ADS)

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.

Gianotti, Rebecca L.; Bomblies, Arne; Eltahir, Elfatih A. B.

2009-08-01

453

Clues to galaxy activity from rich cluster simulations  

NASA Technical Reports Server (NTRS)

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.

Evrard, August E.

1990-01-01

454

A physically-based abrasive wear model for composite materials  

SciTech Connect

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.

Lee, Gun Y.; Dharan, C.K.H.; Ritchie, Robert O.

2001-05-01

455

Energy dissipation and tool-workpiece contact in ultra-precision machining  

NASA Astrophysics Data System (ADS)

An experimental investigation was conducted to examine the dissipation of mechanical energy when machining at depths of cut less than several micrometers. Cutting and thrust forces which resulted in the orthogonal ultra-precision flycutting of Al 6061-T6 were measured over a range of depth of cut of 20 micrometers down to 0.01 micrometers at a cutting speed of 0.8 m/sec. Measurement of the tool-workpiece contact length indicated that it may become the characteristic length scale when machining at submicrometer depths of cut. Evidence suggests that the process may be viewed as transitioning from a cutting-dominant to plowing/sliding indentation-dominant process. Tool edge condition was seen to have a significant effect on the resulting forces when the depth of cut was below the tool edge radius.

Lucca, D. A.; Seo, Y. W.; Rhorer, R. L.

1994-07-01

456

The sphingosine 1-phosphate receptor S1P2 maintains germinal center B cell homeostasis and promotes niche confinement  

PubMed Central

Sphingosine-1-phosphate receptor-2 (S1P2)-deficient mice develop diffuse large B cell lymphoma. However, the role of S1P2 in normal germinal center (GC) physiology is unknown. Here we show that S1P2-deficient GC B cells outgrow their wild-type counterparts in chronically-established GCs. We find that S1P2-, G12–G13- and p115RhoGEF-mediated antagonism of Akt regulates cell viability and is required for growth control in chronically proliferating GCs. We also find that S1P2 inhibits GC B cell responses to follicular chemoattractants and helps confine cells to the GC. Moreover, S1P2 overexpression promotes centering of activated B cells within the follicle. We suggest that by inhibiting Akt activation and migration, S1P2 helps restrict GC B cell survival and localization to an S1P-low niche at the follicle center. PMID:21642988

Green, Jesse A.; Suzuki, Kazuhiro; Cho, Bryan; Willison, L. David; Palmer, Daniel; Allen, Christopher D.C.; Schmidt, Timothy H.; Xu, Ying; Proia, Richard L.; Coughlin, Shaun R.; Cyster, Jason G.

2011-01-01

457

Ultrarelativistic electromagnetic pulses in plasmas  

NASA Technical Reports Server (NTRS)

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.

Ashour-Abdalla, M.; Leboeuf, J. N.; Tajima, T.; Dawson, J. M.; Kennel, C. F.

1981-01-01

458

Tribological behavior of Ti-Al-Si-C-N hard coatings deposited by hybrid arc-enhanced magnetron sputtering  

SciTech Connect

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.

Wu Guizhi; Ma Shengli; Xu Kewei; Chu, Paul K [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049 (China); Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon (Hong Kong)

2012-03-15

459

Slurry Erosion Performance Study of Detonation Gun-Sprayed WC-10Co-4Cr Coatings on CF8M Steel Under Hydro-Accelerated Conditions  

NASA Astrophysics Data System (ADS)

In the current investigation, cermet coatings (WC-10Co-4Cr) were deposited on CF8M steel by detonation gun (D-gun) thermal spraying process. Subsequently, the slurry erosion behaviors of the coated and bare steels were investigated using a high-speed erosion test rig. Slurry collected from an actual hydro power plant was used as the abrasive media. Effects of concentration (ppm), average particle sizes and rotational speed on the slurry erosion behaviors of coated and bare steels under different experimental conditions were studied. The analysis of eroded samples was done using SEM and stylus profilometry. Signatures of microcutting, fracture of well-bonded WC grains, and fragmentations were observed on the eroded surface of WC-10Co-4Cr coating, while signatures of formation of plowing, lips, shearing of platelet, formation of crater, and micro-cutting were observed on the eroded surface of CF8M steel.

Bhandari, Sanjeev; Singh, Harpreet; Kumar, Harmesh; Rastogi, Vikas

2012-09-01

460

Shell-Shocked: The Interstellar Medium Near Cygnus X-1  

E-print Network

We conduct a detailed case-study of the interstellar shell near the high-mass X-ray binary, Cygnus X-1. We present new WIYN optical spectroscopic and Chandra X-ray observations of this region, which we compare with detailed MAPPINGS III shock models, to investigate the outflow powering the shell. Our analysis places improved, physically motivated constraints on the nature of the shockwave and the interstellar medium (ISM) it is plowing through. We find that the shock is traveling at less than a few hundred km/s through a low-density ISM (jet and/or O-star wind can both be central drivers of the shockwave. We conclude that the source of the Cygnus X-1 shockwave is far from solved.

Sell, P H; Richards, E; Maccarone, T J; Russell, D M; Gallo, E; Fender, R; Markoff, S; Nowak, M

2014-01-01

461

A method for sampling waste corn  

USGS Publications Warehouse

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.

Frederick, R.B.; Klaas, E.E.; Baldassarre, G.A.; Reinecke, K.J.

1984-01-01

462

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)

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.

Rehder, J. B. (principal investigator)

1974-01-01

463

"Astronomers Anticipate Meteor "Storm" on November 18th"  

NSDL National Science Digital Library

The annual Leonid meteor shower, named for its emanation from the constellation Leo, will blow past Earth on November 18, 2001. Astronomers predict that North America will get the most spectacular Leonid shower it has seen in 35 years. "Earth is about to plow through a cloud of space dust that could light up our skies with celestial fireworks," notes Alan MacRobert, senior editor for Sky and Telescope (S&T) magazine. For more about the Leonids, refer to Sky and Telescope online. From the press release above, users can access a special report, peak activity prediction tables, images and QuickTime animations (intended for the press), and a .pdf of the S&T print article on the Leonid showers.

2001-01-01

464

Zero-tillage and corn production in eastern Canada  

SciTech Connect

During the summer of 1979, a zero-tillage experiment was conducted in which corn (maize) was grown on 68 different plots representing different soil structural status. Sixty-four of the plots had been subjected to 16 different compaction and tillage treatments and corn grown on them. No machinery traffic had been introduced to these plots since the spring of 1978. Four new plots were established which had been subjected to conventional tillage methods, those being plowing in the fall of 1978 and disc harrowing in the spring of 1979. Corn was hand seeded into all the plots and the growth, development and yield of the crop measured. Several times over the growing season, soil dry bulk density, soil moisture content and soil temperature were measured. Observation of days to emerge, tassel and silk showed that the zero-till plots performed much better than the control plots.

Raghavan, G.S.V.; Taylor, F.; Negi, S.; Douglas, E.; McKyes, E.; Tessier, S.; Burrows, J.

1981-01-01

465

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)

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 vegetated treatments, CT, MT and NT showed a lower efficiency in reducing water losses than soil losses. Water losses by runoff during a number of events were of the same order of magnitude for all the management systems studied here; which was mainly true when the volume of rainfall was high and the lag between successive events was small. In general, soil losses in the autumn-winter seasons were lower than under the spring-summer seasons. Soil losses showed a positive correlation with rainfall erosivity. However, the degree of dependence between these two variables decreased as the efficiency of soil management in controlling soil erosion increased. The large soil and water losses in the BS and CT treatments suggest that there is a need to implement soil conservation measures in the study region. In this context soil conservation would take advantage from soil cover by previous crop residue as well as from terrace building. Acknowledgement: This work was partly supported by Spanish Ministry of Education (Project CGL2005-08219-C02).

Bertol, Ildegardis; Vidal Vázquez, Eva; Paz Ferreiro, Jorge

2010-05-01

466

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)

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.

Belnap, Jayne; Reynolds, Richard L.; Reheis, Marith C.; Phillips, Susan L.; Urban, Frank E.; Goldstein, Harland L.

467

Assessment of high resolution digital elevation model for deep humus-rich sediments delineation at a plot scale  

NASA Astrophysics Data System (ADS)

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.

Penížek, Vít; Zádorová, Tereza

2014-05-01

468

Multicolor Photometry of the Type II Cepheid Prototype W Virginis  

NASA Astrophysics Data System (ADS)

We present the results of recent long-term BVRCIC photometric monitoring of the type II Cepheid prototype W Virginis. These new observations, made during the 2006 and 2007 observing season, represent the longest homogeneous, multicolor light curve of W Vir to date. The BVRCIC light and color curves show conclusively that W Vir exhibits modest but detectable cycle-to-cycle variations, the cause of which appears to be multiperiodicity rather than nonlinearity. We combined our V-band data with the five available years of ASAS-3 V-band photometry to obtain a 6.5 yr light curve that we then analyzed to obtain the pulsation spectrum of W Vir. We find a best-fit period P0 = 17.27134 days; along with this period and the integer-ratio harmonics P0/2 through P0/5 inclusive, we clearly detect two additional periods, P1 and Plow, that are close to but not exactly 2P0/3 and 2P0, respectively. The former, P1 = 11.52562 days, we interpret to be the first overtone mode; the latter, Plow = 34.59760 days, is close to the beat period of (P - P)-1, as well as to the value of 2P0. We interpret the previously reported but thus far unconfirmed descriptions of alternating minima as manifestations of this multiperiodicity. Finally, we use the period derived from the V-band light curve to define a new ephemeris: HJDmax = 2,452,758.172 + 17.27134E. We compiled an (O - C) diagram spanning 75 yr from 1932 to 2007 using a variety of published photometric data and visual observations from the American Association of Variable Star Observers and derived a period-change term for the ephemeris equal to -9.9 × 10-7E2, indicating a period decrease.

Templeton, M. R.; Henden, A. A.

2007-11-01

469

Coronal Mass Ejection Evolution in the Inner Heliosphere Geometry and Speed  

NASA Astrophysics Data System (ADS)

We present the results from two Coronal Mass Ejections (CMEs) which occurred in February 2003 and February 2004. They were tracked through LASCO within 30 R_\\odot and then later as Interplanetary CMEs (ICMEs) through SMEI from 80-150 R_\\odot. Both events were also associated with erupting filaments, followed by post-eruptive arcades which were observed by EIT, providing information on the three-dimensional (3D) direction of propagation. Assuming radial propagation, this allowed 3D reconstructions of the CME/ICME geometry, along with corrected (not sky plane projected) measurements of the distance-time (d-t) plots for each event out to ~0.5 AU. We present the results from an investigation of geometry evolution comparing CME/ICME images in LASCO and SMEI. The results show that the curvature becomes more sharply concave outward (i.e. the curvature is away from the Sun), suggesting that the ICME footprints remain fixed to the Sun even at 0.5 AU. We also present two models describing the evolution of the CME/ICMEs at large distances from the Sun and consider two drag models: Aerodynamic Drag and Snow Plow models. There was little difference between these, and their d-t profiles matched well with the SMEI data for the first event. The second event showed a net acceleration between the LASCO and SMEI fields of view and we find that we can match the data for this event well by introducing a driving Lorentz Force to the drag models. ICME mass almost doubled as a result of swept up solar wind material from the Snow Plow model. We discuss possible physical reasons for the difference between the speed evolutions for the two events.

Howard, T. A.; Johnston, J. C.; Webb, D. F.

2006-12-01

470

Phosphorus forms and chemistry in the soil profile under long-term conservation tillage: a phosphorus-31 nuclear magnetic resonance study.  

PubMed

In many regions, conservation tillage has replaced conventional tilling practices to reduce soil erosion, improve water conservation, and increase soil organic matter. However, tillage can have marked effects on soil properties, specifically nutrient redistribution or stratification in the soil profile. The objective of this research was to examine soil phosphorus (P) forms and concentrations in a long-term study comparing conservation tillage (direct drilling, "No Till") and conventional tillage (moldboard plowing to 20 cm depth, "Till") established on a fine sandy loam (Orthic Humo-Ferric Podzol) in Prince Edward Island, Canada. No significant differences in total carbon (C), total nitrogen (N), total P, or total organic P concentrations were detected between the tillage systems at any depth in the 0- to 60-cm depth range analyzed. However, analysis with phosphorus-31 nuclear magnetic resonance spectroscopy showed differences in P forms in the plow layer. In particular, the concentration of orthophosphate was significantly higher under No Till than Till at 5 to 10 cm, but the reverse was true at 10 to 20 cm. Mehlich 3-extractable P was also significantly higher in No Till at 5 to 10 cm and significantly higher in Till at 20 to 30 cm. This P stratification appears to be caused by a lack of mixing of applied fertilizer in No Till because the same trends were observed for pH and Mehlich 3-extractable Ca (significantly higher in the Till treatment at 20 to 30 cm), reflecting mixing of applied lime. The P saturation ratio was significantly higher under No Till at 0 to 5 cm and exceeded the recommended limits, suggesting that P stratification under No Till had increased the potential for P loss in runoff from these sites. PMID:21043270

Cade-Menun, Barbara J; Carter, Martin R; James, Dean C; Liu, Corey W

2010-01-01

471

Nitrogen, tillage, and crop rotation effects on carbon dioxide and methane fluxes from irrigated cropping systems.  

PubMed

Long-term effects of tillage intensity, N fertilization, and crop rotation on carbon dioxide (CO(2)) and methane (CH(4)) flux from semiarid irrigated soils are poorly understood. We evaluated effects of: (i) tillage intensity [no-till (NT) and conventional moldboard plow tillage (CT)] in a continuous corn rotation; (ii) N fertilization levels [0-246 kg N ha(-1) for corn (Zea mays L.); 0 and 56 kg N ha(-1) for dry bean (Phaseolus vulgaris L.); 0 and 112 kg N ha(-1) for barley (Hordeum distichon L.)]; and (iii) crop rotation under NT soil management [corn-barley (NT-CB); continuous corn (NT-CC); corn-dry bean (NT-CDb)] on CO(2) and CH(4) flux from a clay loam soil. Carbon dioxide and CH(4) fluxes were monitored one to three times per week using vented nonsteady state closed chambers. No-till reduced (14%) growing season (154 d) cumulative CO(2) emissions relative to CT (NT: 2.08 Mg CO(2)-C ha(-1); CT: 2.41 Mg CO(2)-C ha(-1)), while N fertilization had no effect. Significantly lower (18%) growing season CO(2) fluxes were found in NT-CDb than NT-CC and NT-CB (11.4, 13.2 and 13.9 kg CO(2)-C ha(-1)d(-1) respectively). Growing season CH(4) emissions were higher in NT (20.2 g CH(4) ha(-1)) than in CT (1.2 g CH(4) ha(-1)). Nitrogen fertilization and cropping rotation did not affect CH(4) flux. Implementation of NT for 7 yr with no N fertilization was not adequate for restoring the CH(4) oxidation capacity of this clay loam soil relative to CT plowed and fertilized soil. PMID:19704145

Alluvione, Francesco; Halvorson, Ardell D; Del Grosso, Stephen J

2009-01-01

472

Arteriovenous extracorporeal lung assist allows for maximization of oscillatory frequencies: a large-animal model of respiratory distress  

PubMed Central

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

Muellenbach, Ralf M; Kuestermann, Julian; Kredel, Markus; Johannes, Amelie; Wolfsteiner, Ulrike; Schuster, Frank; Wunder, Christian; Kranke, Peter; Roewer, Norbert; Brederlau, Jorg

2008-01-01

473

Contribution of macroporosity to infiltration into a continuous corn no-tilled watershed: Implications for contaminant movement  

NASA Astrophysics Data System (ADS)

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.

Edwards, W. M.; Shipitalo, M. J.; Norton, L. D.

1988-12-01

474

Stellar Interlopers Caught Speeding Through Space  

NASA Technical Reports Server (NTRS)

[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.

2009-01-01

475

Evaluating TerraSAR-X for the identification of tillage occurrence over an agricultural area in Canada  

NASA Astrophysics Data System (ADS)

Tillage practices can affect the long term sustainability of agricultural soils as well as a variety of soil processes that impact the environment. The benefits of reduced tillage and no-till practices over agriculture fields are well documented and include: (1) significant reductions in wind and water erosion mitigating nutrient and pesticide runoff into waterways; (2) increasing and/or maintaining soil organic matter; (3) increasing biological activity and improving soil structure; and (4) increasing soil carbon and its sequestration. Information on tillage activities assists in implementing policies and programs to promote beneficial management practices (BMPs), and in monitoring the success of these initiatives. Agriculture and Agri-Food Canada supports environmentally responsible agriculture and has identified this as one of their priorities. Thus, tillage information requirements have become increasingly important to a number of programs and policies within the department. Rapid, accurate and objective methods are required to map and monitor tillage activities. Earth observing satellites can assist with targeting and monitoring land management activities. For the last decade, research has clearly demonstrated that complementary information provided by both optical and radar satellite sensors are fundamental in developing an agricultural land management monitoring system. Launched in June 2007, the TerraSAR-X is a radar satellite acquiring data at the X-band frequency (9.6 GHz). The application of TerraSAR-X data for conservation tillage mapping has been somewhat limited, and thus this study investigates its use in determining tillage occurrence. An HH-HV TerraSAR-X image was acquired on November 4, 2009 and ground data were also collected characterizing tillage conditions at the time of acquisition. Backscatter responses were analyzed to identify tillage occurrence and to differentiate between untilled, chiseled and moldboard ploughed fields. Preliminary analysis showed that HH polarization can better contribute to tillage discrimination than compared to HV polarization and that the backscatter response can be used to discriminate untilled fields from ones that are moldboard ploughed. However, chiseled fields were often confused with highroughness (rms height~1.30 cm) untilled fields and moldboard ploughed fields. Fully polarimetric X-band radar datasets could potentially contribute more information to mapping tillage conditions.

Pacheco, Anna M.; McNairn, Heather; Merzouki, Amine

2010-10-01

476

Lunar surface operations. Volume 3: Robotic arm for lunar surface vehicle  

NASA Technical Reports Server (NTRS)

A robotic arm for a lunar surface vehicle that can help in handling cargo and equipment, and remove obstacles from the path of the vehicle is defined as a support to NASA's intention to establish a lunar based colony by the year 2010. Its mission would include, but not limited to the following: exploration, lunar sampling, replace and remove equipment, and setup equipment (e.g. microwave repeater stations). Performance objectives for the robotic arm include a reach of 3 m, accuracy of 1 cm, arm mass of 100 kg, and lifting capability of 50 kg. The end effectors must grip various sizes and shapes of cargo; push, pull, turn, lift, or lower various types of equipment; and clear a path on the lunar surface by shoveling, sweeping aside, or gripping the obstacle present in the desired path. The arm can safely complete a task within a reasonable amount of time; the actual time is dependent upon the task to be performed. The positioning of the arm includes a manual backup system such that the arm can be safely stored in case of failure. Remote viewing and proximity and positioning sensors are incorporated in the design of the arm. The following specific topic are addressed in this report: mission and requirements, system design and integration, mechanical structure, modified wrist, structure-to-end-effector interface, end-effectors, and system controls.

Shields, William; Feteih, Salah; Hollis, Patrick

1993-01-01

477

Geology of the fushun coalfield, Liaoning Province, People's Republic of China  

USGS Publications Warehouse

The Fushun coalfield is located in Liaoning Province 45 km east of Shenyang in a relatively small east-west-trending exposure of Mesozoic and Cenozoic rocks surrounded by Precambrian terrane. The coal is included in a sequence of early Tertiary rocks consisting of Paleocene basalt and tuff, and Eocene coal, oil shale and mudstone. These units have been folded into a syncline that plunges gently to the east. The overturned north limb of this fold has been partly removed by a thrust fault. The principal coal beds are low-sulfur subbituminous and bituminous in rank, are of limnic origin, and are contained in the 55-m-thick Eocene Guchengzi Formation. The field, which has been active since the turn of the century, has both open pit and underground mines. The largest operation is the West Open Pit mine, which measures 2.0 km wide, 6.6 km long, and 300 m deep. Coal is mined by means of power shovels, trucks, and an electric rail system. Oil shale from the Eocene Jijuntun Formation is also mined. ?? 1990.

Johnson, E.A.

1990-01-01

478

Tissue lead concentrations and shot ingestion in nine species of waterbirds from the Camargue (France).  

PubMed

This study investigates the relationship among lead exposure (shot ingestion), current lead impregnation (liver lead values), current and previous lead impregnation (bone lead values), and lead excretion (feather lead) in nine species of waterbird from the Camargue (Rhone river delta), France. Results indicate that for individuals there is no readily predictable relationship between ingested shot and liver or bone lead concentrations. However, at the "population" level, and interspecifically, significant positive relationships exist between the susceptibility to shot ingestion and the degree of lead impregnation. Shoveler (Anas clypeata) proved to be an exception, with a high level of shot ingestion and no elevated tissue lead values. This is probably related to dietary factors. Species with a high degree of current lead contamination tended to be those that had also previously absorbed elevated levels of lead. Feather lead concentrations were not clearly related to the vulnerability of a species to shot ingestion or lead poisoning. There was no significant absorption of arsenic and antimony from gunshot associated with lead absorption. PMID:1280587

Pain, D J; Amiard-Triquet, C; Sylvestre, C

1992-10-01

479

Predicting resource partitioning and community organization of filter-feeding dabbling ducks from functional morphology.  

PubMed

Resource partitioning due to interspecific differences in phenotype is a key component of ecological and evolutionary theory, but the relationship between morphology and resource use is poorly understood for most species. In addition, ecologists often assume that morphological differences cause distinct resource preferences between species. Using mechanistic models that combine bill morphology and kinetics, I show that filter-feeding dabbling ducks face a morphology-mediated trade-off between particle size selection and water filtration rate. When detritus is absent, mallards (Anas platyrhynchos) and northern shovelers (Anas clypeata) should maximize their intake rates and exhibit high overlap in prey size. When prey and detritus co-occur, species should separate prey from detritus by size, leading to reduced intake rates and size-based prey partitioning. Models for both species correctly predicted variation in water filtration rates, particle retention probabilities, and prey ingestion rates due to variation in prey size, the presence of detritus, and experimental modification of bill morphology. Because species have both shared and distinct resource preferences, duck communities should exhibit strong density-dependent niche shifts (i.e., centrifugal dynamics), a finding that contradicts previous studies that assumed that ducks have distinct resource preferences only. Centrifugal dynamics may be widespread among filter feeders because of the common cost of separating prey from detritus. PMID:17230398

Gurd, D Brent

2007-03-01

480

Endozoochorous dispersal of aquatic plants: does seed gut passage affect plant performance?  

PubMed

The ingestion of seeds by vertebrates can affect the germinability and/or germination rate of seeds. It is, however, unclear if an earlier germination as a result of ingestion affects later plant performance. For sago pondweed, Potamogeton pectinatus, the effects of seed ingestion by ducks on both germinability and germination rate have been previously reported from laboratory experiments. We performed an experiment to determine the effects of seed ingestion by ducks on germination, seedling survival, plant growth and asexual multiplication. Both at the start and end of the winter, seeds were fed to three captive shovelers (Anas clypeata) and planted outdoors in water-filled containers. Plant biomass and its allocation to vegetative parts (shoot and roots), tubers, and seeds were determined in autumn. More duck-ingested seeds than control (uningested) seeds germinated in early winter, but this difference disappeared for seeds planted in late winter, when the treatments were first stratified for 3 mo. None of the variables for measuring seedling survival and plant performance varied between treatments. Under our experimental conditions (no herbivory or competition), ingestion by ducks in early winter resulted in increased performance for seeds surviving gut passage due to enhanced seed germinability, without other costs or benefits for the seedlings. PMID:21652448

Figuerola, Jordi; Santamaría, Luis; Green, Andy J; Luque, Isabel; Alvarez, Raquel; Charalambidou, Iris

2005-04-01

481

Avian influenza surveillance in hunter-harvested waterfowl from the Gulf Coast of Texas (November 2005-January 2006).  

PubMed

The objectives of our study were to determine prevalence of avian influenza viruses (AIV) on wintering grounds on the Texas Gulf Coast, USA, and to compare real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) and virus isolation for detection of AIV in cloacal swabs from wild waterfowl. Cloacal swabs were collected from hunter-harvested waterfowl from November 2005 to January 2006 at four wildlife management areas. Seven AIV were isolated from four species of ducks: Green-winged Teal (Anas crecca) in November; Blue-winged Teal (Anas discors) in November; Mottled Duck (Anas fulvigula) in December, and Northern Shoveler (Anas clypeata) in January. Prevalence of AIV for each of these species during the sampling period was 1.4, 2, 6, and 0.6%, respectively. The AIV subtypes detected were H1N2, H1N4, H4N6, H6N2, and H10N7, all previously reported in North American waterfowl. Our study identified AIV subtypes not previously reported on the Texas Gulf Coast and provides baseline data for a multiyear surveillance project. PMID:18436675

Ferro, Pamela J; El-Attrache, John; Fang, Xingwang; Rollo, Susan N; Jester, Adam; Merendino, Todd; Peterson, Markus J; Lupiani, Blanca

2008-04-01

482

Avian influenza viruses and avian paramyxoviruses in wintering and breeding waterfowl populations in North Carolina, USA.  

PubMed

Although wild ducks are recognized reservoirs for avian influenza viruses (AIVs) and avian paramyxoviruses (APMVs), information related to the prevalence of these viruses in breeding and migratory duck populations on North American wintering grounds is limited. Wintering (n=2,889) and resident breeding (n=524) ducks were sampled in North Carolina during winter 2004-2006 and summer 2005-2006, respectively. Overall prevalence of AIV was 0.8% and restricted to the winter sample; however, prevalence in species within the genus Anas was 1.3% and was highest in Black Ducks (7%; Anas rubripes) and Northern Shovelers (8%; Anas clypeata). Of the 24 AIVs, 16 subtypes were detected, representing nine hemagglutinin and seven neuraminidase subtypes. Avian paramyxoviruses detected in wintering birds included 18 APMV-1s, 15 APMV-4s, and one APMV-6. During summers 2005 and 2006, a high prevalence of APMV-1 infection was observed in resident breeding Wood Ducks (Aix sponsa) and Mallards (Anas platyrhynchos). PMID:21270016

Goekjian, Virginia H; Smith, Jennifer T; Howell, Doug L; Senne, Dennis A; Swayne, David E; Stallknecht, David E

2011-01-01

483

Parasites of waterfowl, from southwest Texas: III. The green-winged teal, Anas crecca.  

PubMed

Seventy of 72 green-winged teal, Anas crecca, from southwest Texas were infected with parasites. Seventeen species of endoparasites were recorded: Notocotylus attenuatus, Zygocotyle lunata, Typhlocoelum sisowi, Echinostoma revolutum, Hypoderaeum conoideum, Dendritobilharzia pulverulenta, Cloacotaenia megalops, Sobolevicanthus gracilis, Sobolevicanthus krabbeella, Gastrotaenia cygni, Amidostomum acutum, Amidostomum anseris, Tetrameres crami, Echinuria uncinata, Corynosoma constrictum, Polymorphus minutus. Also recorded were five species of ectoparasites: Trinoton querquedulae, Anaticola crassicornis, Anatoecous icterodes, Holomenopon setigerum and Epidermoptes sp. and the sacrosporidian, Sarcocystis rileyi. Anatoecous icterodes is a new host record for A. crecca. Sobolevicanthus gracilis, S. krabbeella, T. sisowi, and D. pulverulenta are new records for A. crecca in North America. Sobolevicanthus krabbeella is also a new record for North America. Fall juveniles had greater mean parasite intensity (29) than fall (19) and spring adults (19). Juveniles were infected with fewer species of parasites (17) than adults (20). Simpson's index was very low (0.11) indicating a diverse parasite fauna. Sorenson's index of similarity indicated that the parasite fauna for green-winged teal from southwest Texas was more similar to the shoveler's, Anas clypeata, parasites reported from southwest Texas (55%) than to green-winged teal parasites reported from eastern Canada (41%) and New Brunswick, Canada (21%). PMID:6788963

Canaris, A G; Mena, A C; Bristol, J R

1981-01-01

484

Morphologic and molecular characterization of the sarcocysts of Sarcocystis rileyi (Apicomplexa: Sarcocystidae) from the mallard duck ( Anas platyrhynchos ).  

PubMed

Macroscopic sarcocysts are often observed in ducks, but at present their taxonomic status remains uncertain because ducks serve as intermediate hosts for several such parasites in the genus Sarcocystis . One such species, Sarcocystis rileyi , was long ago established to involve the northern shoveler duck ( Anas clypeata ) and the striped skunk ( Mephitis mephitis ) as its intermediate and definitive hosts, respectively. Here, we employed light microscopy, electron microscopy, and DNA sequencing to more precisely describe diagnostic attributes of parasites presumed to represent S. rileyi occurring in a naturally-infected mallard duck ( Anas platyrhynchos ). By light and transmission electron microscopy, sarcocysts from the mallard duck resembled the S. rileyi described from A. clypeata . We document 18S, ITS-1, and 28S rDNA sequences from the mallard duck, the first for S. rileyi from any host. Sequences of conserved and variable portions of nuclear ribosomal DNA indicated that S. rileyi is related to, but distinct from, parasites employing opossums as their definitive host (including Sarcocystis neurona and Sarcocystis falcatula ). Diagnostic ultrastructural features and nucleotide sequences should aid in future studies and communications regarding this parasitic taxon, which lends itself to experimentation because its sarcocysts are macroscopic and easily excised from infected birds. PMID:20496959

Dubey, J P; Rosenthal, B M; Felix, T A

2010-08-01

485

High Prevalences of Lead Poisoning in Wintering Waterfowl in Spain  

PubMed

Some Mediterranean wetlands are found between the areas with the highest prevalence of lead pellet exposure for waterfowl in the world. To assess the situation in Spain, availability of pellets in sediments and rates of ingestion by waterfowl were determined in four important wetlands: Albufera de València, El Fondo, Tablas de Daimiel, and Doñana (Guadalquivir Marshes). Lead pellet density in sediment was maximum in the Albufera, with 2.8 million pellets/ha. In Tablas de Daimiel, where hunting was banned in 1965, about 1.0 million pellets/ha were found. Percentages of shot waterfowl with ingested pellets were maximum in the wetlands on the Mediterranean coast (El Fondo and Albufera de València): 87.5% of common pochard (Aythya ferina) and approximately 33% of mallard (Anas platyrhynchos) and shoveler (Anas clypeata) contained ingested pellets. It was found that mallards with > 5 µg/g dry weight of lead in the liver had 8.5% lower body condition and 7.7% less body weight than birds with lower lead concentrations. Moreover, lead poisoning was diagnosed as the cause of death in 16 out of 75 birds, mainly greylag geese (Anser anser), found dead in some of these zones. PMID:9680527

Mateo; Belliure; Dolz; Aguilar Serrano JM; Guitart

1998-08-01

486

INTEGRATED ROBOT-HUMAN CONTROL IN MINING OPERATIONS  

SciTech Connect

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.

George Danko

2006-04-01

487

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

SciTech Connect

T-Rex stands for Transuranic Storage Area Remote Excavator that is dedicated to the retrieval of above ground waste containers and overburden at the Radioactive Waste Management Complex (RWMC) located at the Idaho National Engineering Laboratory. There are a number of sites around the world containing (transuranic) (TRU), low level (LLW), and hazardous wastes that requires teleoperated, heavy lift manipulators with long reach and high precision to handle the materials stored there. Remote operation of equipment will reduce the risk to personnel to as-low-as-reasonably-achievable (ALARA) levels. The T-Rex is designed to fulfill this requirement at relatively 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), and multiple end effectors with quick changeout capability. This paper describes the conversion of an off-the-shelf excavator to a machine utilizi