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1

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

2

Shoveling in a materials world  

SciTech Connect

Shovels. How do you find the right one for your mine. Where do you start. Because capital costs for a fleet of shovels run into millions of dollars, proper planning can save you hundreds of thousands of dollars down the road. To help you make the most intelligent choice and use of these equipment resources, the authors analyzed ''electric'' shovels (also called cable shovels or wire rope shovels) and hydraulic shovels. This article is designed to answer those questions you may have concerning shovel selection, productivity, and operation.

Zaburunov, S.A.

1988-07-01

3

Optimized design for the plow of a submarine plowing trencher  

NASA Astrophysics Data System (ADS)

The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the towing force of a vessel. A multi-objective genetic algorithm based on analytical models of the plow surface has been examined and applied in efforts to obtain optimal design of the plow. For a specific soil condition, the draft force and moldboard surface area which are the key parameters in the working process of the plow are optimized by finding the corresponding optimal values of the plow blade penetration angle and two surface angles of the main cutting blade of the plow. Parameters such as the moldboard side angle of deviation, moldboard lift angle, angular variation of the tangent line, and the spanning length are also analyzed with respect to the force of the moldboard surface along soil flow direction. Results show that the optimized plow has an improved plow performance. The draft forces of the main cutting blade and the moldboard are 10.6% and 7%, respectively, less than the original design. The standard deviation of Gaussian curvature of moldboard is lowered by 64.5%, which implies that the smoothness of the optimized moldboard surface is much greater than the original.

Gong, Hanyang; Yuan, Ruhua; Xing, Xiaodong; Wang, Liquan; Wang, Zhipeng; Gong, Haixia

2013-03-01

4

Semi-automatic control system for hydraulic shovel  

Microsoft Academic Search

A semi-automatic control system for a hydraulic shovel has been developed. Using this system, unskilled operators can operate a hydraulic shovel easily and accurately. A mathematical control model of a hydraulic shovel with a controller was constructed and a control algorithm was developed by simulation. This algorithm was applied to a hydraulic shovel and its effectiveness was evaluated. High control

Hirokazu Araya; Masayuki Kagoshima

2001-01-01

5

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

6

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

7

Metallic Nanostructures via Static Plowing Lithography  

E-print Network

Metallic Nanostructures via Static Plowing Lithography Lon A. Porter, Jr., Alexander E. Ribbe features. Nanostructured materials continue to be the focus of intense research because of their promise approach for the preparation and patterning of metallic nanostructures via static plowing lithography

Porter Jr., Lon A.

8

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

9

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

10

The snow-shoveler's ST elevation myocardial infarction.  

PubMed

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. The investigators describe their experience with 6 patients presenting with ST elevation myocardial infarctions, 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, most patients reported here had the traditional cardiac risk factors of hypertension, hyperlipidemia, diabetes mellitus, tobacco use, and sedentary lifestyle. Unique to this case series, however, was that the 4 patients who had histories of coronary artery disease and previous coronary artery stenting all presented with subacute stent thromboses documented on coronary angiography performed emergently. Moreover, these patients constituted 25% of all subacute stent thromboses diagnosed in the cardiac catheterization laboratory in the preceding 12 months. In conclusion, these findings suggest that in typically sedentary individuals with cardiac risk factors or histories 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 histories of coronary stent placement, considering that these 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

2010-08-15

11

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

12

Key performance indicators for electric mining shovels and oil sands diggability  

Microsoft Academic Search

A shovel performance monitoring study was undertaken in two oil sands mines operated by Syncrude Canada Ltd. using performance data obtained from P&H 4100 TS and BOSS electric mining shovels. One year of shovel performance data along with geological, geotechnical, and climatic data were analyzed. The approach adopted was to use current and voltage data collected from hoist and crowd

Sibabrata Patnayak

2006-01-01

13

Rotylenchulus reniformis below Plow Depth Suppresses Cotton Yield and Root Growth  

PubMed Central

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 ? 0.05), whereas chisel fumigation at 168 liters/ha 43 cm deep reduced nematode numbers only in the top 61 cm (P ? 0.001). Manual placement of fumigant increased yield 92%; chisel fumigation increased yield 88% (P ? 0.005). A second experiment in February 2001 placed fumigant 43 or 81 cm deep, or at both 43 and 81 cm. Holes alone had no significant effect on nematode density at planting, midseason or harvest, on root length density at midseason, or on cotton lint yield. Fumigant at 43 cm reduced nematode numbers above fumigant application depth at planting 94% (P ? 0.02), at midseason 37% (P ? 0.09), and at harvest 0%, increasing yield 57% (P ? 0.002). Fumigant at 81 cm reduced nematode numbers above fumigant application depth at planting 86% (P ? 0.02), at midseason 74% (P ? 0.02), and at harvest 48% (P ? 0.01), increasing yield 53% (P ? 0.002). Fumigating at both 43 and 81 cm reduced nematode numbers above 90 cm 94% at planting and 79% at midseason, increased midseason root-length density 14-fold below 76 cm, and doubled yield (P ? 0.02 in all cases). PMID:19262875

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

2005-01-01

14

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

15

EVALUATION OF FORESTRY PLOW ENERGY REQUIREMENTS FOR SITE PREPARATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this field study, data were collected to determine energy requirements of trailing site preparation plows and the magnitudes of dynamic forces experienced by a plow during normal operation and during impact with stumps or other obstructions. Drawbar pull data were collected from five different t...

16

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

17

Cheatgrass communities: effect of plowing on species composition and productivity  

SciTech Connect

Thirty-year-old cheatgrass communities were disturbed by experimentally plowing small plots, Cheatgrass, Bromus tectorum L., promptly invaded the plowed plots. Plowing enhanced plant production at the high elevation site, 520 m, but depressed production at the low elevation site, 320 m, during a year of near normal precipitation in 1976. During the 1977 drought, plant production was very low at both study sites, but productivity was most depressed at the low elevation site. Possible factors in the explanation of results are discussed.

Rickard, W.H.; Cline, J.F.

1980-01-01

18

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

19

Forming mechanism of integral serrated high fins by plowing-extruding based on variational feed  

Microsoft Academic Search

Plowing-extruding tool was designed and plowing-extruding process was investigated. Then, a manufacturing method of integral serrated high-finned tube, plowing-extruding based on variational feed was proposed, in which plowing-extruding tool moved forward at two different feeds, f1 and f2, in turn. In this method, overlaps that are usually avoided in practical application were utilized to manufacture high fins and average height

Zhen-ping WAN; Hui YAN; Yong TANG

2010-01-01

20

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

Microsoft Academic Search

Chionactis occipitalis (Western Shovel-nosed Snake) is a small colubrid snake inhabiting the arid regions of the Mojave, Sonoran, and Colorado deserts.\\u000a Morphological assessments of taxonomy currently recognize four subspecies. However, these taxonomic proposals were largely\\u000a based on weak morphological differentiation and inadequate geographic sampling. Our goal was to explore evolutionary relationships\\u000a and boundaries among subspecies of C. occipitalis, with particular

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

2008-01-01

21

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

22

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

23

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

24

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

25

Long term effects of profile-modifying deep plowing on soil properties and crop yield  

Technology Transfer Automated Retrieval System (TEKTRAN)

Insufficient plant available soil water limits dryland crop yields on the semiarid Southern Great Plains. Deep plowing to eliminate dense subsoil layers may increase soil water by increased infiltration and rooting, but the duration of treatment effects must be sufficiently long to recoup plowing co...

26

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

E-print Network

imagery. My second chapter considers Grant Wood's 1931 painting "Fall Plowing," a depiction of a steel walking plow, to focus on the function, history, and impact of the implement itself. The next two chapters focus on artistic products of the Dust Bowl...

Meyer, Kate

2011-05-31

27

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

28

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

SciTech Connect

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

Shrestha, R.K.; Lal, R.; Jacinthe, P.A. [Ohio State University, Columbus, OH (United States). School of Environmental & Natural Resources

2009-05-15

29

Comparison between dynamic plowing lithography and nanoindentation methods  

NASA Astrophysics Data System (ADS)

Two different methods of nanolithography, namely dynamic plowing lithography (DPL) and indentation by means of force-displacement curves (FDI), have been compared by performing them on two different polymers, poly (methylmethacrylate) and polystyrene. No fundamental differences can be found out in the efficiency of the two methods, i.e., in the depth of the lithographed structure as a function of the scanning parameters. The main drawback of FDI is that it is much more time consuming than DPL. On the other hand, when the sample is lithographed with DPL, the border walls that surround the lithographed structure are very much bigger than the border walls created through FDI. The physicochemical properties of the border walls created through DPL have been investigated. Several experimental data reveal that such border walls are very much softer and looser than unmodified polymers and suggest that during DPL the fast oscillating tip is able to break polymer chains. This does not happen with FDI, where border walls are simply made up of the material carved out by the tip. A method to eliminate these undesirable border walls is suggested.

Cappella, B.; Sturm, H.

2002-01-01

30

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

31

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

Anyone with a history of heart disease. Anyone with high blood pressure or high cholesterol levels While Shoveling Snow If you have any of the risk factors (heart disease, high cholesterol, high blood-656-5420 or 1-800-571-0668, Fax:802-656-5422 Snow shoveling is one of the most high-intensity exercises you can

Hayden, Nancy J.

32

SHORT-TERM VERSUS CONTINUOUS CHISEL AND NO-TILL EFFECTS ON SOIL CARBON AND NITROGEN  

Technology Transfer Automated Retrieval System (TEKTRAN)

For various management reasons, North American crop farmers are more likely to practice limited-duration no-till than continuous no-till. Previously no-tilled soils may be plowed intermittently. Little is known about effects of short duration no-till on organic carbon (C) and total nitrogen (N) rela...

33

Delayed plowing of forages within potato rotation reduces nitrate leaching losses  

NASA Astrophysics Data System (ADS)

The potato industry plays an important role in the economics in Prince Edward Island (PEI), Canada. Intensive potato production has been conducted on sandy soil underlain by a semi-confined or unconfined sandstone aquifer, which provides all the drinking water and a large majority of stream flow on the island. Typically, potato is grown in rotation with grain underseeded with forages, with the latter being plowed down in the fall of the third season. High levels of nitrate leaching losses from the potato production systems have adversely affected both groundwater and associated surface water quality. Beneficial Management Practices (BMPs) were proposed for maintaining optimal crop production while mitigating the nitrate contamination in PEI. But there is limited information on the environmental performance of the BMPs in commercial fields. The potentials of delayed forage plowing from fall to spring to reduce nitrate losses were evaluated in commercial fields at two separated sites in PEI during October 2010 and March 2013. At Site 1, two tile-drained fields were paired for spring vs. fall plowing treatments (with pre-plow herbicidal treatment); weekly tile-drainage samples were collected to evidence the effects of the treatments. At Site 2, a field was split in half for spring vs. fall plowing treatments (without pre-plow herbicidal treatment). Shallow piezometers were installed at the upper and lower ends of the field for water sampling, with the upper end one indicating the effects of shallow groundwater inflow and the lower ones evidencing the combined effects of groundwater inflow and drainage from plowing treatments. Soil drainage was estimated through coupled LEACHN and MODFLOW simulations. Nitrate leaching losses were calculated as the integration of measured leached nitrate concentrations and simulated drainage. Field monitoring showed that nitrate leaching mainly occurred during the offseason. Nitrate leaching during the forage phase were estimated to be 36 and 18 kg N/ha from the fall and spring plowed fields at Site 1, respectively. The differences of leached nitrate were mainly attributed to pre-plow herbicidal treatment associated with fall plowing. Respective nitrate leaching losses were estimated to be 54 and 32 kg N/ha from the fall and spring plowed fields at Site 2. The differences of leached nitrate at Site 2 were likely due to the different timing of tillage. The results suggested that postponing plowing of forages and associated herbicidal treatments until spring reduced nitrate leaching. Nitrate leaching losses derived exclusively from the decay of plow down forages were estimated to account for 16-21% of the overall N in the plants, implying that a significant amount of N in the forages were carried over into the subsequent crop phase. This large carried-over N pool creates an opportunity for the growers to save costs on fertilizer N by crediting some of the organic N while reducing the risk of nitrate leaching to groundwater.

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

2013-12-01

34

Contact laser transurethral surgery using a sapphire chisel probe firing Nd:YAG  

NASA Astrophysics Data System (ADS)

This is a report on a modified technique for use of a contact laser for transurethral surgery to improve voiding in spinal core injury patients. To produce a channel for voiding, chisel sapphire tips are used to deliver adequate Nd:YAG laser energy to vaporize tissue blocking the urethral passage. We present data on 51 spinal cord injury patients (range 29 - 76 years) who had contact laser surgery in the past 22 months. Urodynamic studies showed detrusor sphincter dyssynergia in 82% of patients. On cystoscopic examination prior to surgery, 39% had associated enlargement of the prostate and/or bladder-neck stenosis. Thirty-one percent also had associated strictures in the bulbous urethra. For transurethral resection of the sphincter, a 12 o'clock incision was made by passing the contact probe repeatedly and/or buttonholing and then cutting the overlying tissue. For vaporization of the prostate and eradication of urethral strictures, the contact chisel probe was passed repeatedly over the surface and also buttonholes were drilled. The overlying tissue was incised with the laser chisel. The buttonhole technique expedited the procedure for creation of an adequate urethral channel for voiding. During surgery, there was minimal blood loss of about 25 - 50 ml per procedure except in 2 patients who lost 100 to 150 ml. All except 4 patients voided satisfactorily within 1 to 8 days (mean 2.7 days) when the catheter was removed following surgery. The initial 4 patients who did not void well are also voiding satisfactorily following repeat surgery.

Perkash, Inder

1995-05-01

35

Metallurgical Investigation of a Steel Miner's Chisel From Ponte Val Gabbia III Site  

NASA Astrophysics Data System (ADS)

Recent research on ancient ferrous artefacts belonging to different historical periods has indicated significant differences in various parameters characterizing the slags entrapped in these artefacts, in cases where they were obtained by using different production methods. Such differences have been observed by comparing "ancient period" artefacts with "subsequent period" artefacts. "Ancient period" products were obtained by direct reduction of iron ore, without carburizing and at temperatures below the melting point of the reduced sponge iron. In the "subsequent period", the indirect process started to be introduced, with the production, in a first reduction stage, of a liquid cast iron that had to be converted to wrought iron during a second fining operation. The understanding of the characterizing parameters of the slags has in fact progressed to the point where they represent a useful tool not only for inferring the origins of the starting ore but also for distinguishing between direct or indirect production. In the present research work, an accurate study of the entrapped slags has been carried out on an artefact from the Val Gabbia III site, identified in previous studies as a miner's chisel. This study aims to carry out further metallurgical investigation into the miner's chisel microstructure and the entrapped slags in order to help ascertain which production method was in use at the Val Gabbia III site; in fact, based on the intrinsic characteristics of the chisel, and the fact that the site where it was found, i.e. layers of the V-VI cent AD in Val Gabbia III site, was characterized by the presence of an almost 3.5 kg cast iron block, previous investigators were led to suppose that it may be a very early site of indirect iron smelting. While the slag characterizing parameters obtained in the present investigation appear to be consistent with published results related to the direct method, the discussion on the relationship between the indirect method production effects on entrapped slag and the experimental findings substantiate, although not definitively, the hypothesis that the production method of the miner's chisel is indirect.

Cornacchia, Giovanna; Faccoli, Michela; Roberti, Roberto

2014-12-01

36

Metallurgical Investigation of a Steel Miner's Chisel From Ponte Val Gabbia III Site  

NASA Astrophysics Data System (ADS)

Recent research on ancient ferrous artefacts belonging to different historical periods has indicated significant differences in various parameters characterizing the slags entrapped in these artefacts, in cases where they were obtained by using different production methods. Such differences have been observed by comparing "ancient period" artefacts with "subsequent period" artefacts. "Ancient period" products were obtained by direct reduction of iron ore, without carburizing and at temperatures below the melting point of the reduced sponge iron. In the "subsequent period", the indirect process started to be introduced, with the production, in a first reduction stage, of a liquid cast iron that had to be converted to wrought iron during a second fining operation. The understanding of the characterizing parameters of the slags has in fact progressed to the point where they represent a useful tool not only for inferring the origins of the starting ore but also for distinguishing between direct or indirect production. In the present research work, an accurate study of the entrapped slags has been carried out on an artefact from the Val Gabbia III site, identified in previous studies as a miner's chisel. This study aims to carry out further metallurgical investigation into the miner's chisel microstructure and the entrapped slags in order to help ascertain which production method was in use at the Val Gabbia III site; in fact, based on the intrinsic characteristics of the chisel, and the fact that the site where it was found, i.e. layers of the V-VI cent AD in Val Gabbia III site, was characterized by the presence of an almost 3.5 kg cast iron block, previous investigators were led to suppose that it may be a very early site of indirect iron smelting. While the slag characterizing parameters obtained in the present investigation appear to be consistent with published results related to the direct method, the discussion on the relationship between the indirect method production effects on entrapped slag and the experimental findings substantiate, although not definitively, the hypothesis that the production method of the miner's chisel is indirect.

Cornacchia, Giovanna; Faccoli, Michela; Roberti, Roberto

2015-01-01

37

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

38

[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

39

Regulatory Guidance Letter 86-01 SUBJECT: Exemptions to CWA -Plowing  

E-print Network

, and forest products" from the definition of a discharge of dredged or fill material 33 CFR 323.2(j) and (1, and forest products and meeting the definition in Section 323.4 will never involve a discharge of dredged it is not for the purpose of producing food, fiber or forest products. Also, the use of a plow to divert a braided stream

US Army Corps of Engineers

40

Biting performance and skull biomechanics of a chisel tooth digging rodent (Ctenomys tuconax; Caviomorpha; Octodontoidea).  

PubMed

Biting performance is a key factor in vertebrate groups possessing particular food habits. In subterranean rodents that use the incisors as a digging tool, apart from requirements related to gnawing abrasive diets, the force exerted at the incisors tips must be sufficient to break down soils that are often exceedingly compact. The subterranean genus Ctenomys diversified in the southern portion of South America closely associated with the relatively open environments that characterize that region. This genus is considered a "claw and chisel tooth digger," that is, during the excavation of their galleries, the animals break down the soil with both the fore-claws and the incisors. We report here measurements of in vivo bite force in one of the largest species of the genus, C. tuconax, which occupies highland grasslands with compacted soils. We document the combined use of claws and incisors observed under field conditions, also providing measurements of soil compaction in the habitat occupied by this species. We report estimates of bite force at the level of the incisors and cheek teeth calculated from the physiological cross-sectional area of jaw muscles. To this aim, anatomical and biomechanical analyses of the mandibular apparatus were performed in preserved specimens. We found that C. tuconax bites with a higher force than expected for a mammal of its size. To assess anatomical correlates of biting performance, the morphology of the skull and jaw, and incisor second moment of area were compared with those of other caviomorph rodents with different lifestyle. PMID:23203312

Becerra, Federico; Casinos, Adrià; Vassallo, Aldo Iván

2013-02-01

41

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

NASA Technical Reports Server (NTRS)

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

Miyoshi, Kazuhisa

2001-01-01

42

1) The snow plow problem (R.P. Agnew): It began to snow early in the morning and the snow continued to fall throughout the  

E-print Network

1) The snow plow problem (R.P. Agnew): It began to snow early in the morning and the snow continued to fall throughout the day at a constant rate. Assume that the speed at which a snow plow is able to clear a road is inversely proportional to the height of the snow. The snow plow started at 5 a.m. and had

Prigozhin, Leonid

43

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

44

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

45

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

E-print Network

Keeping Corn Farmers Seeing Green As recently as 100 years ago, farmers plowed their fields, as corn is a key commodity in the U.S. agricultural economy, with a value nearing $66 billion in 20101 . The success of the corn industry is not only vital to farmers and the agricultural industry, but also

46

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

PubMed Central

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

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

2013-01-01

47

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

PubMed

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

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

2013-01-01

48

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

49

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

PubMed

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

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

NASA Astrophysics Data System (ADS)

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

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

2011-08-01

53

An assessment of heavy metal bioaccumulation in Asian swamp eel, Monopterus albus, during plowing stages of a paddy cycle.  

PubMed

Livers and muscles of swamp eels (Monopterus albus) were analyzed for bioaccumulation of heavy metals during the plowing stage of a paddy cycle. Results showed heavy metals were bioaccumulated more highly in liver than muscle. Zinc (Zn) was the highest bioaccumulated metal in liver (98.5 ± 8.95 ?g/g) and in muscle (48.8 ± 7.17 ?g/g). The lowest bioaccumulated metals were cadmium (Cd) in liver (3.44 ± 2.42 ?g/g) and copper (Cu) in muscle (0.65 ± 0.20 ?g/g). In sediments, Zn was present at the highest mean concentration (52.7 ± 2.85 ?g/g), while Cd had the lowest mean concentration (1.04 ± 0.24 ?g/g). The biota-sediment accumulation factor (BSAF) for Cu, Zn, Cd and nickel (Ni) in liver tissue was greater than the corresponding BSAF for muscle tissue. For the three plowing stages, metal concentrations were significantly correlated between liver and muscle tissues in all cases, and between sediment and either liver or muscle in most cases. Mean measured metal concentrations in muscle tissue were below the maximum permissible limits established by Malaysian and U.S. governmental agencies, and were therefore regarded as safe for human consumption. PMID:23666324

Sow, Ai Yin; Ismail, Ahmad; Zulkifli, Syaizwan Zahmir

2013-07-01

54

Movement and Persistence of 1,2-dibromo-3-chloropropane in a Soil with a Plow-pan  

PubMed Central

Movement and persistence of 1,2-dibrotno-3-chloropropane (DBCP) in a Coastal Plain soil containing a sandy plow-pan were enhanced in each of 2 years by subsoiling, increased depth of application, and increased rate of application. DBCP was extracted from the soil with hexane and analyzed by gas chromatography. Subsoiling at a 35-cm depth gave the greatest increase in lateral movement and downward penetration of DBCP in 1975 (a wet year), but bad less effect in 1976 (a dry year). An increased application rate (10 kg/ha vs. 13.5) improved coverage moderately in 1975 by increasing lateral movement, but had little effect in 1976. Increased application depth (18 vs. 35 cm) improved coverage in both years though more in 1976. Deep placement extended DBCP retention time. Rainfall in 1975 probably decreased the number and size of air-filled pores, slowing loss of DBCP to the atmosphere. Because of reduced porosity, the plow-pan was impervious to the passage of DBCP unless disrupted by subsoiling. PMID:19305844

Bernard, E. C.; Hussey, R. S.

1978-01-01

55

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

56

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

Code of Federal Regulations, 2010 CFR

...project or assigned to an afternoon of shoveling snow off the courthouse steps would not...periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may...

2010-07-01

57

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

Code of Federal Regulations, 2012 CFR

...project or assigned to an afternoon of shoveling snow off the courthouse steps would not...periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may...

2012-07-01

58

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

...project or assigned to an afternoon of shoveling snow off the courthouse steps would not...periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may...

2014-07-01

59

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

Code of Federal Regulations, 2013 CFR

...project or assigned to an afternoon of shoveling snow off the courthouse steps would not...periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may...

2013-07-01

60

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

Code of Federal Regulations, 2011 CFR

...project or assigned to an afternoon of shoveling snow off the courthouse steps would not...periods of peak demand, for instance during the snow plowing season or road construction season. The snow plow operator/road crew employee may...

2011-07-01

61

Plow and ridge nanofabrication.  

PubMed

Traditionally, scanning probe lithography tools are limited in resolution by the radius of curvature of the tip used. Herein, an approach is described for patterning the ridge of piled-up polymer that naturally occurs when a scanning probe is pressed against a soft surface. The use of this phenomenon to transfer patterns to hard materials with 20 nm resolution is demonstrated. PMID:23427089

Shim, Wooyoung; Brown, Keith A; Zhou, Xiaozhu; Rasin, Boris; Liao, Xing; Schmucker, Abrin L; Mirkin, Chad A

2013-09-23

62

Measuring and modeling alachlor dissipation in soil.  

E-print Network

??Field and laboratory experiments evaluated the overall dissipation of alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide) and the effect of no-till and chisel-plow tillages on alachlor leaching and dissipation.… (more)

Weed, Dee Anna Jo

1995-01-01

63

Application method: impacts on atrazine and alachlor movement, weed control, and corn yield in three tillage systems  

Microsoft Academic Search

Banding herbicides reduces the agrochemical input compared to broadcast applications, and thereby reduces negative environmental impacts of herbicides. This study evaluated the impact of three tillage systems (ridge tillage, chisel plow, and moldboard plow) and two preemergence herbicide application methods (band and broadcast) on atrazine and alachlor movement, weed control, and corn (Zea mays L.) yield on two soils, one

S. A. Clay; D. E. Clay; W. C. Koskinen; R. K. Berg

1998-01-01

64

Suppression of Adult Lesser Mealworm (Coleoptera: Tenebrionidae) Using Soil Incorporation of Poultry Manure  

Microsoft Academic Search

The effectiveness of manure incorporation in reducing the numbers of adult lesser mealworms emerging from caged-layer poultry manure applied to agricultural Þelds was examined in summer 2002 and 2004. Incorporation treatments included control (no incorporation), disk (7-cm depth), harrow (15-cm depth), chisel plow (30-cm depth), and moldboard plow (33-cm depth) on silt loam soils in New York state. An estimated

Phillip E. Kaufman; Colleen Reasor; J. Keith Waldron; Donald A. Rutz

2005-01-01

65

Twin Oaks Landscape, Inc. is seeking additional highly-qualified green industry professionals to manage and operate our growing business; such candidates shall possess attributes of accountability, integrity, passion,  

E-print Network

Twin Oaks Landscape, Inc. is seeking additional highly-qualified green industry professionals Experienced Snow Plow Skid and/or Truck Drivers Snow Shovelers Executive Summary Twin Oaks Landscape, Inc. (Twin Oaks) is a company created to revolutionize the landscape industry in southeast Michigan. "We

Isaacs, Rufus

66

Tillage-induced CO 2 loss across an eroded landscape  

Microsoft Academic Search

Soil carbon (C) losses and soil translocation from tillage operations have been identified as causes of soil degradation and soil erosion. The objective of this work was to quantify the variability in tillage-induced carbon dioxide (CO2) loss by moldboard (MP) and chisel (CP) plowing across an eroded landscape and relate the C loss to soil properties. The study site was

D. C. Reicosky; M. J. Lindstrom; T. E. Schumacher; D. E. Lobb; D. D. Malo

2005-01-01

67

Tillage and crop residue effects on soil carbon and carbon dioxide emission in corn-soybean rotations.  

PubMed

Soil C change and CO2 emission due to different tillage systems need to be evaluated to encourage the adoption of conservation practices to sustain soil productivity and protect the environment. We hypothesize that soil C storage and CO2 emission respond to conservation tillage differently from conventional tillage because of their differential effects on soil properties. This study was conducted from 1998 through 2001 to evaluate tillage effects on soil C storage and CO2 emission in Clarion-Nicollet-Webster soil association in a corn [Zea mays L.]-soybean [Glycine max (L.) Merr.] rotation in Iowa. Treatments included no-tillage with and without residue, strip-tillage, deep rip, chisel plow, and moldboard plow. No-tillage with residue and strip-tillage significantly increased total soil organic C (TC) and mineral fraction C (MFC) at the 0- to 5- and 5- to 10-cm soil depths compared with chisel plow after 3 yr of tillage practices. Soil CO2 emission was lower for less intensive tillage treatments compared with moldboard plow, with the greatest differences occurring immediately after tillage operations. Cumulative soil CO2 emission was 19 to 41% lower for less intensive tillage treatments than moldboard plow, and it was 24% less for no-tillage with residue than without residue during the 480-h measurement period. Estimated soil mineralizable C pool was reduced by 22 to 66% with less intensive tillage treatments compared with moldboard plow. Adopting less intensive tillage systems such as no-tillage, strip-tillage, deep rip, and chisel plow and better crop residue cover are effective in reducing CO2 emission and thus improving soil C sequestration in a corn-soybean rotation. PMID:15758095

Al-Kaisi, Mahdi M; Yin, Xinhua

2005-01-01

68

Tillage and nutrient source effects on water quality and corn grain yield from a flat landscape.  

PubMed

Beneficial effects of leaving residue at the soil surface are well documented for steep lands, but not for flat lands that are drained with surface inlets and tile lines. This study quantified the effects of tillage and nutrient source on tile line and surface inlet water quality under continuous corn (Zea mays L.) from relatively flat lands (<3%). Tillage treatments were either fall chisel or moldboard plow. Nutrient sources were either fall injected liquid hog manure or spring incorporated urea. The experiment was on a Webster-Canisteo clay loam (Typic Endoaquolls) at Lamberton, MN. Surface inlet runoff was analyzed for flow, total solids, NO(3)-N, NH(4)-N, dissolved P, and total P. Tile line effluent was analyzed for flow, NO(3)-N, and NH(4)-N. In four years of rainstorm and snowmelt events there were few significant differences (p < 0.10) in water quality of surface inlet or tile drainage between treatments. Residue cover minimally reduced soil erosion during both snowmelt and rainfall runoff events. There was a slight reduction in mineral N losses via surface inlets from manure treatments. There was also a slight decrease (p = 0.025) in corn grain yield from chisel-plow plots (9.7 Mg ha(-1)) compared with moldboard-plow plots (10.1 Mg ha(-1)). Chisel plowing (approximately 30% residue cover) alone is not sufficient to reduce nonpoint source sediment pollution from these poorly drained flat lands to the extent (40% reduction) desired by regulatory agencies. PMID:15888896

Thoma, David P; Gupta, Satish C; Strock, Jeffrey S; Moncrief, John F

2005-01-01

69

Field Tests with Corn at College Station and Beeville.  

E-print Network

of growing table corn, etc,), because, as it is often said, the heat is too instense. But since the introduction of the more vigor? BEST V AR IET IE S OF CORN. 1 197 ous and hardy ?Mexican June 'Corn,? which is a pure type of the Zea Mays, late summer... from 75 per cent, to 95 per cent. All cultivation was shallow and thorough, as follows: April 25?Plowed with 4-tooth cultivator. May 2?Orrick harrow run between rows, set to a V shape. May 9?Corn thinned and plowed with double shovel. May 16?Corn...

Pittuck, B. C.; Connell, J. H.

1898-01-01

70

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

71

Earthworm response to rotation and tillage in a Missouri claypan soil  

Microsoft Academic Search

Agricultural management practices affect earthworm populations. A field experiment was conducted to determine the effect\\u000a of two rotations and two tillage systems on earthworm population density and biomass in a claypan soil. The rotations were\\u000a soybean\\/corn and wheat\\/corn, and the tillage systems were conventional tillage (chisel plowed and disked) and no-tillage.\\u000a Earthworm and soil samples were collected in fall 1995,

V. C. Hubbard; D. Jordan; J. A. Stecker

1999-01-01

72

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

ERIC Educational Resources Information Center

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

Ewell, Peter T.

2009-01-01

73

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, Håkan

2012-01-01

74

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

NASA Astrophysics Data System (ADS)

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

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

2012-04-01

75

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

76

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

ERIC Educational Resources Information Center

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

Huang, Li-yi

77

Modeling the effects of deep chiseling with DRAINMOD for alluvial soils  

Technology Transfer Automated Retrieval System (TEKTRAN)

DRAINMOD is a drainage model that has been widely used in the shallow water table regions of the US including southeastern US. Therefore, it is important that DRAINMOD realistically simulate surface runoff, infiltration and drainage volume for the surface-seal-formation prone alluvial soils that are...

78

Competition for IL-2 between Regulatory and Effector T Cells to Chisel Immune Responses  

PubMed Central

In this review we discuss how the competition for cytokines between different cells of the immune system can shape the system wide immune response. We focus on interleukin-2 (IL-2) secretion by activated effector T cells (Teff) and on the competition for IL-2 consumption between Teff and regulatory T cells (Treg). We discuss the evidence for the mechanism in which the depletion of IL-2 by Treg cells would be sufficient to suppress an autoimmune response, yet not strong enough to prevent an immune response. We present quantitative estimations and summarize our modeling effort to show that the tug-of-war between Treg and Teff cells for IL-2 molecules can be won by Treg cells in the case of weak activation of Teff leading to the suppression of the immune response. Or, for strongly activated Teff cells, it can be won by Teff cells bringing about the activation of the whole adaptive immune system. Finally, we discuss some recent applications attempting to achieve clinical effects through the modulation of IL-2 consumption by Treg compartment. PMID:22973270

Höfer, Thomas; Krichevsky, Oleg; Altan-Bonnet, Grégoire

2012-01-01

79

Estimating farm machinery complements based on cropmix and farm size  

E-print Network

' Grain Drill Planter 4 row Chisel 28 shank Plow 9 bottom Plow 5 bottom (3) 8, 000 25. 000 32. 500 17, 500 20, 000 37, 500 10, 000 6, 500 8, 500 10, 000 S, 500 7, 000 6, 500 1, 000 (3) 9, 000 25, 0CO 1 5, 0tD 7, 000 10, 5CO 1 S..., OCO 4, 000 9, 500 9, 000 2, 500 20. tm 72, 500 145, 000 5, MO 12, 500 19, 0tm 6, 500 16, 0EI 10, 000 13, 000 15, 000 5, 000 (years) SO. O 12. 0 8. 0 15. 0 15. 0 1 5. 0 20. 0 20. 0 30. 0 10. 0 15. 0 15. 0 40. 0 30. 0 20...

Barrera, Anna Marie

1993-01-01

80

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

81

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

82

ROTYLENCHULUS RENIFORMIS BELOW PLOW DEPTH SUPPRESSES COTTON YIELD AND ROOT GROWTH  

Technology Transfer Automated Retrieval System (TEKTRAN)

Resistance to Rotylenchulus reniformis is absent in Upland cotton (Gossypium hirsutum) and could be introduced from G. barbadense, G. arboretum, or G. herbaceum, but resistant accessions identified in pots need field confirmation. In 2001, six accessions suppressed nematode populations 70 to 98% in...

83

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

ERIC Educational Resources Information Center

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

Lebofsky, Nancy R.

1994-01-01

84

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

PubMed Central

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

2013-01-01

85

Comparison of microbial communities in percolating water from plow layer and subsoil layer estimated by phospholipid fatty acid (PLFA) analysis  

Microsoft Academic Search

The amount and composition of phospholipid fatty acids (PLFAs) in the percolating water taken from different depths of soil (10 cm, PW10; 40 cm, PW40) and floodwater (FW) in a paddy field were compared during the period of rice cultivation. The amounts of PLFAs in PW10, PW40, and FW ranged from 22.6 to 46.2 ?g L, from 22.3 to 54.5

Miho Shimizu; Motoki Hayashi; Kazuo Matsuya; Jun Murase; Makoto Kimura

2002-01-01

86

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...

87

Soil quality differences among long-term no-till irrigated crop rotations to replace burning and plowing continuous wheat  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heavy residue in irrigated wheat (Triticum aestivum L.) production in the Inland Pacific Northwest of the United States (PNW) is a problem often resolved by burning. We investigated the soil quality benefits of a diversified no-till crop rotation with various residue management practices compared t...

88

[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

89

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

NASA Astrophysics Data System (ADS)

E. coli and enterococci are commonly used as pathogen indicators in surface waters. Along with these indicators, pathogenic Salmonella are prevalent in poultry litter, and have the potential to be transported from land-application areas to tile waters and ultimately to impact waters that are used for drinking-water and recreation. The fate and transport of these bacteria to drainage tiles from application fields, and the correlation of fecal indicator bacteria to pathogens in this setting, is poorly understood. In this field study, samples were obtained from poultry litter, soil, and drainage tile waters below chisel-plowed and no-till cornfields in central Iowa where poultry litter was applied each year in late spring prior to planting. Litter was applied at three different rates; commercial fertilizer with no litter, a low application rate based on the nitrogen requirements of the corn (PL1), and double the low rate (PL2). This site is characterized by low sloping (0-9%) Clarion and Nicollet soils, which are derived from glacial till. Samples were collected from April to September for three years (2010-12) when tiles were flowing. Record high precipitation fell during the sampling period in 2010, while 2011 and 2012 were exceptionally dry years at this location. Grab samples were taken directly from flowing tiles after every rainfall event (>2 cm in less than 24 hours) and samples were collected hourly throughout selected events using an automatic sampling device. Concentrations of E. coli, enterococci and Salmonella spp. were quantified by membrane filtration and growth on selective agars. Peak bacteria concentrations following rainfall events were often one order of magnitude higher in tile waters discharging from no-till plots, despite the smaller size and lower tile flow rates at these plots compared to the chisel-plowed plots. Bacteria concentrations regularly varied by two orders of magnitude in response to rainfall events. Bacteria transport via macropores was indicated by a rise in concentrations during or shortly after rainfall, but prior to any increase in tile flow. Macropores located above the tile lines were observed during smoke tests in 2012 confirming significantly greater macropore densities above tile lines in the no-till plots (average 23.2 macropores/m^2) as compared to the chisel-plowed plots (average 1.6 macropores/m^2). Identifiable macropores were generally within a 0.4m-wide zone above the tile lines. While bacterial loading to tile lines was dominated by rainfall-driven events, transport of bacteria to tile lines was observed less than a day after application under unsaturated conditions in 2012. Indicator bacteria concentrations were poorly correlated to Salmonella spp. throughout the study period, with water sample concentrations as high as 4x10^3 cfu/100 ml Salmonella spp. in samples where no E. coli or enterococci were detected. The differences in precipitation from year-to-year had the greatest effect on E. coli concentrations which averaged between 331 - 2140 cfu/100ml under the PL1 and PL2 treatments in 2010, and rarely exceeded 10 cfu/100ml in the month after litter application during dry years. Enterococci were similarly affected, while dry conditions did not result in lower average Salmonella spp. counts.

Hruby, C.; Soupir, M.

2012-12-01

90

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

91

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

92

Describing soil surface microrelief by crossover length and fractal dimension  

NASA Astrophysics Data System (ADS)

Accurate description of soil surface topography is essential because different tillage tools produce different soil surface roughness conditions, which in turn affects many processes across the soil surface boundary. Advantages of fractal analysis in soil microrelief assessment have been recognised but the use of fractal indices in practice remains challenging. There is also little information on how soil surface roughness decays under natural rainfall conditions. The objectives of this work were to investigate the decay of initial surface roughness induced by natural rainfall under different soil tillage systems and to compare the performances of a classical statistical index and fractal microrelief indices. Field experiments were performed on an Oxisol at Campinas, São Paulo State (Brazil). Six tillage treatments, namely, disc harrow, disc plow, chisel plow, disc harrow + disc level, disc plow + disc level and chisel plow + disc level were tested. Measurements were made four times, firstly just after tillage and subsequently with increasing amounts of natural rainfall. Duplicated measurements were taken per treatment and date, yielding a total of 48 experimental surfaces. The sampling scheme was a square grid with 25×25 mm point spacing and the plot size was 1350×1350 mm, so that each data set consisted of 3025 individual elevation points. Statistical and fractal indices were calculated both for oriented and random roughness conditions, i.e. after height reading have been corrected for slope and for slope and tillage tool marks. The main drawback of the standard statistical index random roughness, RR, lies in its no spatial nature. The fractal approach requires two indices, fractal dimension, D, which describes how roughness changes with scale, and crossover length, l, specifying the variance of surface microrelief at a reference scale. Fractal parameters D and l, were estimated by two independent self-affine models, semivariogram (SMV) and local root mean square (RMS). Both algorithms, SMV and RMS, gave equivalent results for D and l indices, irrespective of trend removal procedure, even if some bias was present which is in accordance with previous work. Treatments with two tillage operations had the greatest D values, irrespective of evolution stage under rainfall and trend removal procedure. Primary tillage had the greatest initial values of RR and l. Differences in D values between treatments with primary tillage and those with two successive tillage operations were significant for oriented but not for random conditions. The statistical index RR and the fractal indices l and D decreased with increasing cumulative rainfall following different patterns. The l and D decay from initial value was very sharp after the first 24.4 mm cumulative rainfall. For five out of six tillage treatments a significant relationship between D and l was found for the random microrelief conditions allowing a covariance analysis. It was concluded that using RR or l together with D best allow joint description of vertical and horizontal soil roughness variations.

Vidal Vázquez, E.; Miranda, J. G. V.; Paz González, A.

2007-05-01

93

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

94

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

95

Reclamation techniques in southwestern wyoming.  

PubMed

Bridger Coal Company operates a 5.8 million tpy surface coal mine thrity five miles northeast of Rock Springs. Wyoming. Approximately 20.000 acres are under permit, with disturbance over the life of the mine projected to reach 10,000 acres. Located on the western rim of the continental divide, the mine receives less than 8.5 inches of precipitation annually. Soils in the area are coarse-textured. and problems associated with elevated salinity and sodicity arc encountered.A variety of common reclamation techniques have been modified to reflect these conditions. Soil horizons are segregated during salvage operations (the surface six inches as topsoil and the balance as subsoil). Unsuitable materials are not salvaged. Direct application of soil is used (over 130 acres in 1983) to maximize native plant regeneration and conserve soil fertility. Inter-seeding of seeding failures has proven to be significantly more successful than chisel plowing and reseeding. Broadcast seeding has been ineffective because of strong winds, and a no till drill has been modified to handle diverse seed mixes and rock conditions. The utility of fertilization under typically xeric moisture regimes is being evaluated. A research project has been initiated to assess establishment of a predominately native, diverse seed mix under irrigation, as well as to determine irrigation rates and duration. PMID:24221682

Parady, F E

1985-03-01

96

3D Scanning Lecture courtesy of  

E-print Network

Chisel Marks? Atlas (Accademia) ugnetto ? #12;Why Capture Chisel Marks as Geometry? Day (Medici Chapel) 2 · Mathematically similar to shape from shading, but uses stretch and shrink of a (regular) texture #12;Shape from

Kazhdan, Michael

97

3D Scanning Lecture courtesy of  

E-print Network

Chisel Marks? Atlas (Accademia) ugnetto ? #12;Why Capture Chisel Marks as Geometry? Day (Medici Chapel) 2 Texture · Mathematically similar to shape from shading, but uses stretch and shrink of a (regular) texture

Kazhdan, Michael

98

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

99

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

100

Seasonal dynamics of CO2 efflux in soils amended with composted and thermally-dried sludge as affected by soil tillage systems in a semi-arid agroecosystem  

NASA Astrophysics Data System (ADS)

In semi-arid agricultural soils, seasonal dynamic of soil CO2 efflux (SCE) is highly variable. Based on soil respiration measurements the effects of different management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) was investigated in a long-term field experiment (28 years) conducted on a sandy-loam soil at the experimental station 'La Higueruela' (40o 03'N, 4o 24'W). Both organic amendments were applied at a rate of 30 Mg ha-1 prior to tillage practices. Unamended soils were used as control for each tillage system. SCE was moderate in late spring (2.2-11.8 ?mol CO2 m-2 s-1) when amendments were applied and tillage was performed, markedly decreased in summer (0.4-3.2 ?mol CO2 m-2 s-1), following a moderate increase in autumn (3.4-14.1 ?mol CO2 m-2 s-1), rising sharply in October (5.6-39.8 ?mol CO2 m-2 s-1 ). In winter, SCE was low (0.6-6.5 ?mol CO2 m-2 s-1). In general, SCE was greater in chisel and moldboard tilled soils, and in CS and particularly TSS-amended soils, due to the addition of labile C with these amendments, meanwhile no-tillage soils exhibited smaller increases in C efflux throughout the seasons. Soil temperature controlled the seasonal variations of SCE. In summer, when drought occurs, a general decrease of SCE was observed due to a deficit in soil water content. After drought period SCE jumped to high values in response to rain events ('Birch effect') that changed soil moisture conditions. Soil drying in summer and rewetting in autumn may promotes some changes on the structure of soil microbial community, affecting associated metabolic processes, and enhancing a rapid mineralization of water-soluble organic C compounds and/or dead microbial biomass that acts as an energy source for soil microorganisms. To assess the effects of tillage and amendments on SCE, Q10 values were calculated. Data were grouped into three groups according to soil moisture (0.03-0.10 m3m-3, 0-11-0.21 m3m-3, 0.22-0.30 m3m-3). In general, Q10 values were lower at elevated temperatures when soil moisture contents decreased, confirming that SCE is less sensitive to soil temperature during drought periods. Q10 values were higher in moldboard and chisel tilled soils, possibly due to the incorporation of residues into soil and the increase of soil C substrate, meanwhile in no-tillage part of the organic C pools are likely protected from microorganisms by physico-chemical mechanisms. TSS-amended soils exhibited higher Q10 values than CS, pointing that the biochemical lability of the organic C added with amendments exerts an influence on SCE. Acknowledgements: this research was supported by the Spanish CICYT, Project no. CTM2011-25557.

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

2014-05-01

101

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

102

21 CFR 882.4535 - Nonpowered neurosurgical instrument.  

Code of Federal Regulations, 2013 CFR

...tissue. It includes specialized chisels, osteotomes, curettes, dissectors, elevators, forceps, gouges, hooks, surgical knives, rasps, scissors, separators, spatulas, spoons, blades, blade holders, blade breakers, probes, etc. (b)...

2013-04-01

103

21 CFR 882.4535 - Nonpowered neurosurgical instrument.  

...tissue. It includes specialized chisels, osteotomes, curettes, dissectors, elevators, forceps, gouges, hooks, surgical knives, rasps, scissors, separators, spatulas, spoons, blades, blade holders, blade breakers, probes, etc. (b)...

2014-04-01

104

21 CFR 882.4535 - Nonpowered neurosurgical instrument.  

Code of Federal Regulations, 2011 CFR

...tissue. It includes specialized chisels, osteotomes, curettes, dissectors, elevators, forceps, gouges, hooks, surgical knives, rasps, scissors, separators, spatulas, spoons, blades, blade holders, blade breakers, probes, etc. (b)...

2011-04-01

105

21 CFR 882.4535 - Nonpowered neurosurgical instrument.  

Code of Federal Regulations, 2010 CFR

...tissue. It includes specialized chisels, osteotomes, curettes, dissectors, elevators, forceps, gouges, hooks, surgical knives, rasps, scissors, separators, spatulas, spoons, blades, blade holders, blade breakers, probes, etc. (b)...

2010-04-01

106

21 CFR 882.4535 - Nonpowered neurosurgical instrument.  

Code of Federal Regulations, 2012 CFR

...tissue. It includes specialized chisels, osteotomes, curettes, dissectors, elevators, forceps, gouges, hooks, surgical knives, rasps, scissors, separators, spatulas, spoons, blades, blade holders, blade breakers, probes, etc. (b)...

2012-04-01

107

Effect of site preparation and initial fertilization on the establishment and growth of four plantation tree species used in reforestation of Imperata cylindrica (L.) Beauv. dominated grasslands  

Microsoft Academic Search

Site preparation methods used in reforestation of Imperata cylindrica grasslands were studied in South Kalimantan, Indonesia. In the first trial the effects of strip plowing and complete plowing on the performance of Acacia mangium were compared. In the second trial the effects of complete plowing, herbicide treatment and fertilization (NPK) were compared with four tree species commonly used in Imperata

Antti Otsamo; Göran Ådjers; Tjuk Sasmito Hadi; Jussi Kuusipalo; Kari Tuomela; Risto Vuokko

1995-01-01

108

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

109

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

110

Nitrogen fertilizer rate and crop management effects on nitrate leaching from an agricultural field in central Pennsylvania.  

PubMed

Eighteen pan lysimeters were installed at a depth of 1.2 m in a Hagerstown silt loam soil in a corn field in central Pennsylvania in 1988. In 1995, wick lysimeters were also installed at 1.2 m depth in the same access pits. Treatments have included N fertilizer rates, use of manure, crop rotation (continuous corn, corn-soybean, alfalfa-corn), and tillage (chisel plow-disk, no-till). The leachate data were used to evaluate a number of nitrate leaching models. Some of the highlights of the 11 years of results include the following: 1) growing corn without organic N inputs at the economic optimum N rate (EON) resulted in NO3--N concentrations of 15 to 20 mg l(-1) in leachate; 2) use of manure or previous alfalfa crop as partial source of N also resulted in 15 to 20 mg l(-1) of NO3--N in leachate below corn at EON; 3) NO3--N concentration in leachate below alfalfa was approximately 4 mg l(-1); 4) NO3--N concentration in leachate below soybeans following corn was influenced by fertilizer N rate applied to corn; 5) the mass of NO3--N leached below corn at the EON rate averaged 90 kg N ha(-1) (approx. 40% of fertilizer N applied at EON); 6) wick lysimeters collected approximately 100% of leachate vs. 40-50% collected by pan lysimeters. Coefficients of variation of the collected leachate volumes for both lysimeter types were similar; 7) tillage did not markedly affect nitrate leaching losses; 8) tested leaching models could accurately predict leachate volumes and could be calibrated to match nitrate leaching losses in calibration years, but only one model (SOILN) accurately predicted nitrate leaching losses in the majority of validation treatment years. Apparent problems with tested models: there was difficulty estimating sizes of organic N pools and their transformation rates, and the models either did not include a macropore flow component or did not handle macropore flow well. PMID:12805869

Fox, R H; Zhu, Y; Toth, J D; Jemison, J M; Jabro, J D

2001-10-01

111

Influence for Soil Environment by Continuing use of Biodegradable Plastic  

Microsoft Academic Search

The influence on soil environment by continuing use of the biodegradable plastic films (biodegradable mulching films) in farmland\\u000a was investigated. The difference was not seen in the amount of soil bacteria between mulching film plowing sections and non-plowing\\u000a sections. The total bacteria amount did not increase by the effect of plowing the biodegradable mulching film. Poly-(butylene\\u000a succinate and adipate) (PBSA)

Akihiko Masui; Satoshi Ikawa; Nobuaki Fujiwara; Hiroaki Hirai

112

LIST OF ILLUSTRATIONS. THE SALMON FISBICRIES O F ALASKA.  

E-print Network

.-(l) The Lake Trout (Saluelinuunmaycurh). (2) The Dolly Varden Trout (Saluelinur malma). (3) The Alaskn Grnyling) Scaphirhynchus platyrhynchw; Shovel-nosed Sturgeon. (3) Lepi- sosteue platystomus; Short-nosed Gar

113

40 CFR Table 1 to Subpart Xxxxxx... - Description of Source Categories Affected by This Subpart  

Code of Federal Regulations, 2010 CFR

...to Subpart XXXXXX of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED...except industrial plant overhead and truck-type cranes; dredging machinery; pavers; and power shovels. Also...

2010-07-01

114

7 CFR 301.80-1 - Definitions.  

Code of Federal Regulations, 2013 CFR

...be delegated. Farm tools. An instrument worked or used by hand, e.g., hoes, rakes, shovels, axes, hammers, and saws. Generally infested area. Any part of a regulated area not designated as a suppressive area in accordance with §...

2013-01-01

115

7 CFR 301.80-1 - Definitions.  

Code of Federal Regulations, 2012 CFR

...be delegated. Farm tools. An instrument worked or used by hand, e.g., hoes, rakes, shovels, axes, hammers, and saws. Generally infested area. Any part of a regulated area not designated as a suppressive area in accordance with §...

2012-01-01

116

7 CFR 301.80-1 - Definitions.  

...be delegated. Farm tools. An instrument worked or used by hand, e.g., hoes, rakes, shovels, axes, hammers, and saws. Generally infested area. Any part of a regulated area not designated as a suppressive area in accordance with §...

2014-01-01

117

Get Active  

MedlinePLUS

... Sit-ups Heavy gardening (digging or shoveling) Doing push-ups on the floor or against the wall Lifting ... down after a workout . Do sit-ups and push-ups while you are watching TV tonight. Get tips ...

118

WATERFOWL USE OF WASTEWATER PONDS ON THE IDAHO NATIONAL  

E-print Network

including ruddy ducks (Oxyura jamaicensis), redheads (Aythya americana), northern shoveler (Anas clypeata-winged teal (A. crecca) nested and reared or attempted to rear broods on the INEL ponds. Logistic regression

119

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

120

What to Expect After Heart Surgery  

MedlinePLUS

... housework (scrubbing floors) heavy gardening (shoveling snow, digging) sports: football, soccer, softball, baseball, tennis, bowling, golfing, swimming, water skiing, skydiving, hunting Jogging, bicycling, weightlifting, push-ups motorcycle riding feel ...

121

High-Protein Diets  

MedlinePLUS

... protein diets de-emphasize high-carbohydrate, high-fiber plant foods. These foods help lower cholesterol when eaten ... in Women 6 Low Blood Pressure 7 Shoveling Snow Health Hazards 8 Warning Signs of a Heart ...

122

30 CFR 56.12039 - Protection of surplus trailing cables.  

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar...

2014-07-01

123

30 CFR 56.12039 - Protection of surplus trailing cables.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12039 Protection of surplus trailing cables. Surplus trailing cables to shovels, cranes and similar...

2011-07-01

124

78 FR 56733 - Notice of Inventory Completion: Logan Museum of Anthropology, Beloit College, Beloit, WI  

Federal Register 2010, 2011, 2012, 2013

...adult male. No known individuals were identified. The 83 associated funerary objects are 1 ceramic bowl, 1 ceramic tripod bottle, 1 broken ceramic jar, 2 chipped-stone picks or chisels, 1 ground and scored rectangular stone object, 2...

2013-09-13

125

PORTABLE MACHINE TOOLS The portable machine tools identified and described in this Portable machine tools are powered by self-contained  

E-print Network

with a chisel, star drill, rivet set, or other tool in its nozzle. ELECTRIC EXTENSION CORDS Use the right wire variable speed drills. A variable speed drill is an excellent tool for use as a power screwdriver. Portable

Gellman, Andrew J.

126

What's new in the Writing Center? Appalachian State University's University  

E-print Network

. One has a chiseled jaw and unmistakable confidence. An- other has kind eyes and is hesitant......................4-5 The Leaders, the Loners, and the Lazy.........................7 UWC Word Search...........7

Rose, Annkatrin

127

Methyl bromide alternatives in a bell pepper–squash rotation  

Microsoft Academic Search

Field studies were conducted to evaluate potential methyl bromide alternatives against multiple pests in a bell pepper (Capsicum annum L.) – squash (Cucurbita pepo L.) cropping sequence. Early in the growing season, the most effective treatments in suppressing purple nutsedge (Cyperus rotundus L.) emergence through the polyethylene mulch were methyl bromide, methyl iodide, and chisel-injected 1,3-dichloropropene plus chloropicrin [1,3-D+C35 (chisel)].

T. M. Webster; A. S. Csinos; A. W. Johnson; C. C. Dowler; D. R. Sumner; R. L. Fery

2001-01-01

128

Evaluation of remote sensing in control of pink cotton bollworm  

NASA Technical Reports Server (NTRS)

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

Lewis, L. N. (principal investigator); Coleman, V. B.

1973-01-01

129

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,

130

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

131

Marine pipeline installation system  

Microsoft Academic Search

Apparatus is described for simultaneously laying and burying underwater pipelines. The apparatus employs a rigid, structural frame having skids to contact the ocean floor as the device is propelled across it. A plow on the frame, having a knife edge shear blade at its frontal portion, cuts and parts the ocean floor to form a ditch. The plow is vertically

R. Bushnell; C. R. Gunn

1978-01-01

132

High biomass removal limits carbon sequestration potential of mature temperate pastures  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

133

Ryegrass Cover Crop Effects on Nitrate Leaching in Spring Barley Fertilized with 15 NH4 15 NO3  

Microsoft Academic Search

vated in early autumn and plowed in the spring (Lewan, 1994). However, during the fourth year, after the rye- Cover crops are a management option to reduce NO3 leaching grass was plowed under and not replaced by another under cereal grain production. A 2-yr field lysimeter study was estab- lished in Uppsala, Sweden, to evaluate the effect of a perennial

Lars F. Bergstrom; William E. Jokela

134

Second Africa Rice Congress, Bamako, Mali, 2226 March 2010: Innovation and Partnerships to Realize Africa's Rice Potential 2.12.1 Identification of the main constraints for upland rice crop in direct-seeding  

E-print Network

, the cover plants (live or dead) and the mulches of crop residues fulfill various roles: reducing erosion-based cropping systems (DMC), which not only decrease soil erosion but also increase soil fertility with removal of most of the crop residues, associated with plowing (`plowing'); and a no-till system

Boyer, Edmond

135

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

136

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

137

Visualization of Stress Distribution on Ultrasonic Vibration Aided Drilling Process  

NASA Astrophysics Data System (ADS)

The ultrasonically assisted machining is suitable to achieve sub-millimeter drilling on difficult-to-cut materials such as ceramics, hardened steel, glass and heat-resistant steel. However, it is difficult to observe the high-frequency and micron-scale phenomenon of ultrasonic cutting. In this report, high speed camera based on photoelastic analysis realized the visualization of stress distribution on drilling process. For the conventional drilling, the stress distribution diagram showed the intensive stress occurred under the chisel because the chisel edge of drill produces large plastic deformation. On the other hand, the ultrasonic drilling produced spread stress distribution and stress boundary far away from the chisel. Furthermore, chipping or cracking of inner wall of silica glass was influenced considerably by cutting fluid.

Isobe, Hiromi; Uehara, Yusuke; Okada, Manabu; Horiuchi, Tomio; Hara, Keisuke

138

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...

139

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

140

PAHs And Parking Lots: A Field Study on PAHs Exported From Sealed and Unsealed Parking  

E-print Network

? Abrasion/Plow/Tire tracking Solar/temperature weathering Volatilization Stormwater Wind #12;Sampling surface soil · Air · Tire tracking Sealant applied by contractors in October 2007 #12;Results ­ Stormwater

141

Integrating Cover Crops into Strip-Till Cropping Systems in a Semi-Arid Environment  

E-print Network

species (Medicago polymorpha ‘Armadillo’; M. minima ‘Devine’; M. lupulina ‘BEEBLK’; or Trifolium hirtum ‘Hykon’), or control (plow-tilled/winter fallow). At the Beeville site, the split-split plot treatment was cutting and removal of the cover crops from...

Noland, Reagan Lee

2014-05-02

142

40 CFR 205.151 - Definitions.  

Code of Federal Regulations, 2010 CFR

...vehicle used exclusively for agricultural purposes, or for snow plowing, including self-propelled machines used exclusively in growing, harvesting or handling farm produce. (29) Vehicle means any motorcycle regulated pursuant to this...

2010-07-01

143

The Mechanization of Agriculture.  

ERIC Educational Resources Information Center

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

Rasmussen, Wayne D.

1982-01-01

144

River and Stream Pollution  

MedlinePLUS

... washing into lakes and streams comes from exposed earth. This exposed earth includes plowed fields, construction sites, and areas that ... using new methods to reduce the amount of earth they disturb. Bacteria Bacteria are also a big ...

145

Rangeland Risk Management for Texans: Seeding Rangeland  

E-print Network

planting method. If drilling is not practical, soil/seed contact can be improved by disturbing the soil with roller chopping or ?lite? raking before seed is broadcast. Seeding often follows brush control treatments, especially root plowing. The least...

Rector, Barron S.

2000-11-01

146

76 FR 12405 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals  

Federal Register 2010, 2011, 2012, 2013

...Projects Approved for Collection and Use: Tractor with snow blower and snow plow. Airport security and access control upgrades--design. Airport security and access control upgrades--construction. PFC application, amendments, and...

2011-03-07

147

Tillage and Controlled Drainage-Subirrigated Management Effects on Soil Persistence of Atrazine, Metolachlor, and Metribuzin in Corn  

Microsoft Academic Search

The occurrence of herbicides in surface waters necessitates the de- velopment of management practices to reduce herbicide loss through tile drainage and surface runoff. Four tillage-intercrop systems: mold- board plow (MB), moldboard plow with rye grass (Lolium multiflorum Lam.) intercrop (MB+IC), soil saver (SS), and soil saver with rye grass intercrop (SS+IC), and two water table management treatments: controlled drainage-subirrigation

J. D. Gaynor; C. S. Tan; H. Y. F. Ng; C. F. Drury; T. W. Welacky; I. J. vanWesenbeeck

2000-01-01

148

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

149

Illinois reclaimed soil productivity: Restoration techniques  

SciTech Connect

Consolidation Coal Co. (Consol) has nearly 8,000 acres of high capability and prime farmland reclamation responsibility in Illinois. It has been involved in research in the area of restored soil productivity since 1976 with the University of Illinois and Southern Illinois University, Carbondale. Consol maintains an intensive program to demonstrate and test deep tillage equipment. The research and in-house demonstrations identified soil physical strength (compaction) as the main limiting factor to restoring a soil`s productive capacity. There are two primary ways to address this issue, prevention and amelioration. The former was not an option for Consol because many acres were already reclaimed and the company had a major scraper fleet. Along with other operators in Illinois, Consol started an aggressive search for equipment and techniques that could loosen compacted soils. In 1987 Consol was the first to use the D.M.I.-Super Tiger deep soil plow, originally developed and manufactured by D.M.I., Inc. of Goodfield, Illinois. This plow is composed of a single parabolic, static shank with a 44-inch wide sweep weighing 1,200 pounds. It is capable of plowing 48 inches deep while leaving the top soil in place. A Caterpillar D9L tractor with 460 horsepower is used to pull the plow. In 1990 the decision was made to commit to this equipment as the best technology currently available. In 1994 Consol received a patent waiver from D.M.I. to build its own plow. The Consol built plow has been in use since the summer of 1995. To date, Consol has plowed over 3,900 acres with a D.M.I. plow.

Smout, G. [Consolidation Coal Co., Sesser, IL (United States)

1998-12-31

150

Wheat Production in Texas.  

E-print Network

grain or forage varieties and the development of short stat- ure, strong-strawed varieties for growing under irrigation and high fertility conditions. RECOMMENDED AND ACCEPTABLE WHEAT VARIETIES BY AREAS Area Recommended Acceptable 1 Tascosa Comanche.... wheat are different from those used in dryland production. The land usually is plowed with a disc or moldboard plow and the straw is turned under. Weeds and volunteer wheat are controlled with the usual implements. In many cases the land may...

Atkins, I. M.; Porter, K. B.; Lahr, Keith; Merkle, Owen G.; Futrell, M. C.

1960-01-01

151

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

152

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

153

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

154

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.

155

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

156

Spatial and Temporal Variability of Hydraulic Properties in the Russian River Streambed, Central Sonoma, County, CA  

Microsoft Academic Search

Temporal and spatial variations of flux and vertical hydraulic conductivity were measured in the Russian River streambed in Sonoma County, California. In-situ vertical hydraulic conductivity measurements were made using a modified seepage meter, equipped with mini-piezometers and sediment was collected with a bucket and shovel. We sampled three different streambed (near bank, midpoint, and thalweg) locations at five different sample

M. Laforce; P. Gorman; J. Constantz

2004-01-01

157

29 CFR 1926.601 - Motor vehicles.  

Code of Federal Regulations, 2012 CFR

...whose pay load is loaded by means of cranes, power shovels, loaders, or similar equipment, shall have a cab shield and/or canopy adequate to protect the operator from shifting or falling materials. (7) Tools and material shall be secured to...

2012-07-01

158

29 CFR 1926.601 - Motor vehicles.  

Code of Federal Regulations, 2013 CFR

...whose pay load is loaded by means of cranes, power shovels, loaders, or similar equipment, shall have a cab shield and/or canopy adequate to protect the operator from shifting or falling materials. (7) Tools and material shall be secured to...

2013-07-01

159

29 CFR 1926.601 - Motor vehicles.  

...whose pay load is loaded by means of cranes, power shovels, loaders, or similar equipment, shall have a cab shield and/or canopy adequate to protect the operator from shifting or falling materials. (7) Tools and material shall be secured to...

2014-07-01

160

Research on Tennis Technique and Tactics Decision Support Based on Theory of Association Data Mining  

Microsoft Academic Search

The result of tennis match were great influenced by the level of technique and tactics decision-making, and how to find the characteristics of athletes' technique and tactics from mass data is a urgent problem which is needed to be shoveled, in order to make up the insufficiency of traditional statistical method and provide scientific basis for tennis technique and tactics

Liang Chengjun; Yu Lijuan; Wang Jihong

2010-01-01

161

77 FR 48733 - Transitional Program for Covered Business Method Patents-Definitions of Covered Business Method...  

Federal Register 2010, 2011, 2012, 2013

...Inc. v. Desire2Learn, Inc., 521 F. Supp. 2d 575, 576 (E.D. Tex. 2007) (The parties ``seem to share the misconception, popular in some circles, that motion practice exists to require federal judges to shovel through steaming mounds of...

2012-08-14

162

2014 Soil Testing Form Corn, Forage, Pasture & Hay Instructions  

E-print Network

be taken with a spade, shovel, trowel, soil probe or auger. Mix well, air dry, and remove stones and other calcium, magnesium, potassium, and phosphorus, along with pH and Mehlich lime buffer pH. Results include calculated Cation Exchange Capacity (CEC), base saturation and phosphorus saturation. Organic Matter includes

New Hampshire, University of

163

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

164

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

165

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

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

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

166

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

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

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

167

31. Photographic copy of photograph, photographer unknown, 28 May 1914 ...  

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

31. Photographic copy of photograph, photographer unknown, 28 May 1914 (original print located at U.S. Bureau of Reclamation Upper Columbia Area Office, Yakima, Washington). "View of steam shovel excavation and general view of north borrow pit." - Keechelus Dam, Yakima River, 10 miles northwest of Easton, Easton, Kittitas County, WA

168

p o s t m a r k s For parents and Friends oF the University oF illinois at Urbana-Champaign  

E-print Network

, stone tools and flakes of rock that had been shaped by human hands. "I learned a ton of stuff," said hoping to make archaeology a profession, and can aid the decision-making process for anyone unsure about. They hauled their equipment ­ buckets, shovels, trowels, notebooks and a tool called a pick

Lewis, Jennifer

169

Large mobile mining equipment operating on soft ground T.G. Joseph  

E-print Network

1 Large mobile mining equipment operating on soft ground T.G. Joseph School of Mining & Petroleum. The toll on large mobile mining equipment such as > 327 tonne capacity haulers and > 46 m3 electric for large mobile units, a discussion on the extension of the process to shovel undercarriage and carbody

Joseph, Tim Grain

170

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2012 CFR

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

2012-10-01

171

36 CFR 242.28 - Subsistence taking of shellfish.  

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

2014-07-01

172

50 CFR 100.28 - Subsistence taking of shellfish.  

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

2014-10-01

173

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2013 CFR

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

2013-10-01

174

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2010 CFR

...viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. ...2inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In that portion of the area north of...

2010-10-01

175

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2010 CFR

...viii) A ring net; (ix) A scallop dredge; (x) A sea urchin rake; (xi) A shovel; and (xii) A trawl. ...2inches or greater may be taken or possessed. (6) Bering Sea Area. (i) In that portion of the area north of...

2010-07-01

176

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2012 CFR

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

2012-07-01

177

50 CFR 100.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2011 CFR

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

2011-10-01

178

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2011 CFR

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

2011-07-01

179

36 CFR 242.28 - Subsistence taking of shellfish.  

Code of Federal Regulations, 2013 CFR

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

2013-07-01

180

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

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

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

181

Diesel Engine Technician  

ERIC Educational Resources Information Center

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

Tech Directions, 2010

2010-01-01

182

A Gene Scrapbook A Tribute to Gene Loh  

E-print Network

A Gene Scrapbook A Tribute to Gene Loh on the Occasion of His Retirement Feb 22, 2003 #12;The Early of Technology, 1961 #12;The Missing Years Not much is known about Gene's whereabouts between 1961 until his (probably kelp) for transport by sea. #12;Why did Gene leave Cornell? He got tired of shoveling all

183

Winter Weather Preparedness Have a Plan -Make a Kit -Stay Informed  

E-print Network

, electricity or telephones are cut off for an extended period of time. · Understand stove. Always be cautious using a portable space heater. · Have your car if the electricity goes out Make A Kit: · Windshield scraper, de-icer, snow shovel

Oklahoma, University of

184

Tips for Kids with Type 2 Diabetes: Be Active  

MedlinePLUS

... house, cut the grass, do garden work, rake leaves, or shovel snow. What if you don’t like to exercise? There are a lot of things you can do to be more active. Try these: do sit-ups, lift light weights, or jump rope while you watch TV. Take ...

185

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

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

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

186

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

187

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

E-print Network

158 American Coot Fulica americana 160 Gruidae (Cranes) Sandhill Crane Grus canadensis 162 Wigeon Anas americana 30 Northern Pintail Anas acuta 30 Northern Shoveler Anas clypeata 32 perspicillata 42 Black Scoter Melanitta americana 42 White-winged Scoter Melanitta fusca 42 Bufflehead

Irwin, Darren

188

Sampling Mud in the Elwha River Estuary  

USGS Multimedia Gallery

USGS hydrologic technician Andrew Spanjer shovels Elwha River mud into a bucket for latter analysis in the lab. The USGS is monitoring turbidity at several locations in the Elwha River during the largest dam-removal project in United States history. The mud will be mixed with water to assess how dif...

189

Making a Big Deal about Everyday Objects  

ERIC Educational Resources Information Center

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

Masse, Don

2010-01-01

190

Reserves Project Breeding information is important  

E-print Network

observing during period Cover all habitat types Check your species ID Highlight each species New splits 00893 ...... South African Shelduck 00903 ...... Cape Shoveler 00944 ...... African Black Duck 00956 ...... Yellow-billed Duck 00960 ...... Red-billed Teal 00972 ...... Cape Teal 00987 ...... Hottentot Teal 00991

de Villiers, Marienne

191

SMOKEY THE BEAR SUTRA Gary Snyder  

E-print Network

SMOKEY THE BEAR SUTRA Gary Snyder Once in the Jurassic about 150 million years ago, the Great Sun THE BEAR. A handsome smokey­colored brown bear standing on his hind legs, show­ ing that he is aroused and watchful. Bearing in his right paw the Shovel that digs to the truth beneath ap­ pearances; cuts the roots

Alexander, Roger K.

192

17. Steam construction trains along construction of sublevel rightofway through ...  

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

17. Steam construction trains along construction of sub-level right-of-way through east side of Cleveland, just west of Shaker Square (Moreland Circle): 'Working in cut of Shaker Boulevard East of Woodhill Road; Steam Shovel filling train of dump cars'. 1915 - Shaker Heights Rapid Transit Line, Cleveland, Cuyahoga County, OH

193

16. Photocopied August 1978. CANAL SECTION I, LOOKING EAST, AUGUST ...  

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

16. Photocopied August 1978. CANAL SECTION I, LOOKING EAST, AUGUST 21, 1900. NOTE THE DUMP TRAIN ENGINES PUSHING THE TRAIN OF DUMP CARS AWAY FROM THE STEAM SHOVEL. (62) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

194

17. Photocopied August 1978. CANAL SECTION II, NEAR ASHMUN STREET, ...  

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

17. Photocopied August 1978. CANAL SECTION II, NEAR ASHMUN STREET, LOOKING WEST, DECEMBER 7, 1900. ONE OF THE CITY'S NEW BRIDGES OVER THE CANAL IS IN THE BACKGROUND. TEMPORARY DUMP TRACKS, DUMP TRAINS AND DUMP TRAIN LOCOMOTIVES, AND STEAM SHOVELS ARE ALL SHOWN IN OPERATION. (106) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

195

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

196

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

E-print Network

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 acuta vagrant Garganey Anas querquedula vagrant Hottentot Teal Anas hottentota Southern Pochard Netta

de Villiers, Marienne

197

A stochastic optimization approach to mine truck C. H. TA{, J. V. KRESTA{, J. F. FORBES*{ and H. J. MARQUEZ  

E-print Network

A stochastic optimization approach to mine truck allocation C. H. TA{, J. V. KRESTA{, J. F. FORBES, Edmonton, Alberta, T6G-2V4, Canada In the mining industry, truck assignment is an important and complex; Chance-constrained; Oilsand mining 1. Introduction In the open-pit mining industry, trucks and shovels

Marquez, Horacio J.

198

Summer 2012 BOSTONIAPHOTOGRAPHS BY MELODY KOMYEROV CAS BIOLOGIST PROBES  

E-print Network

shovel after each fresh snow, they hope to chart the effects of what might appear to be a passing-zone winter soil needs snow cover to keep it from freezing and allow it to carry on its role in plant growthSummer 2012 BOSTONIAPHOTOGRAPHS BY MELODY KOMYEROV CAS BIOLOGIST PROBES THE IMPACT OF SNOW

Spence, Harlan Ernest

199

12 | iit magazine As spring relegates a harsh winter to the historic almanacs,  

E-print Network

shoveling snow to early planting, including a summertime favorite--strawberries. Britt Burton plant foods rich in polyphenols can help minimize the deleterious effects of a common American meal plant foods in an effort to better understand their health- promoting properties. As Burton

Heller, Barbara

200

Influence of Subsurface Irrigation and Organic Additions on Top and Root Growth of Field Corn'  

E-print Network

Influence of Subsurface Irrigation and Organic Additions on Top and Root Growth of Field Corn' W. H Quartzipsamments) soil from Delaware to determine the effect of organic additions and type of irrigation on corn was made to superimpose corn rows di- rectly above the chisel openings. Irrigation types were subsurface

Sparks, Donald L.

201

Contact laser sphincterotomy: further experience and longer follow-up  

Microsoft Academic Search

I report here the use of a crystal chisel contact tip firing Nd:YAG laser for transurethral sphincterotomy in 76 consecutive spinal cord injury patients. Their mean age was 53 years (range 26 to 77 years). Fifty-four (72%) were complete motor (Frankel A and B) and 21 (28%) were incomplete lesions (Frankel C and D) They were evaluated with multichannel urodynamic

Inder Perkash

1996-01-01

202

A New Grid Bar Design for a Modified Cylinder Cleaner  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

203

SOIL CO2 FLUX IN CONVENTIONAL AND ORGANIC CROPPING SYSTEMS: COMPARISON OF MEASUREMENT METHODS AND RELATIONSHIP WITH SOIL MOISTURE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Accurate measurement of soil carbon dioxide (CO2) flux is necessary to evaluate the effects of cropping systems on global warming potential and to provide accurate estimates of carbon (C) budgets. Soil CO2 fluxes, soil temperature and volumetric water content (VWC) were measured in no till, chisel ...

204

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

ERIC Educational Resources Information Center

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

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

205

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

206

Large-Scale Acquisition of Feature-Based Conceptual Representations from Textual Corpora  

E-print Network

.poibeau@ens.fr)3, Anna Korhonen (alk23@cam.ac.uk)2 1 Centre for Speech, Language and the Brain, Department concepts like TIGER, APPLE and CHISEL constitute a fundamental part of people's coherent mental representa studies. Currently, the largest set of norms available is that collected by Ken McRae and col- leagues

Boyer, Edmond

207

Empirical relationships for soil organic carbon transport from agricultural watersheds in Ohio  

Technology Transfer Automated Retrieval System (TEKTRAN)

Improved quantification is needed for long-term soil organic carbon (SOC) transport in runoff at watershed scales. Coshocton wheel samplers were used to collect runoff samples from no-till and chisel-till watersheds in corn (Zea mays) and soybean (Glycine max) rotations over 13 years. Samples were a...

208

WOUND COMPARTMENTALIZATION POTENTIAL AND BORER DAMAGE IN GREEN ASH  

Microsoft Academic Search

Green ash trees that exhibited strong Wall 2 com- partmentalization of chisel wounds made in the trunk had less wood discoloration associated with ash borer activity than did weak compartmentalizing trees. The wood of weak compart- mentalizers was extensively colonized by microorganism s (bacteria and stain fungi) and many such trees were declining. Despite the fact that both strong and

Frank S. Santamour

209

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

210

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

211

Transnational Pharmaceutical Corporations and Neo-Liberal Business Ethics in India  

Microsoft Academic Search

The author critiques the expedient application of market valuation principles by the transnational corporations and other large firms in the Indian pharmaceutical industry on a number of issues like patents, pricing, irrational drugs, clinical trials, etc. He contends that ethics in business is chiseled and etched within the confines of particular social structures of accumulation. An ascendant neo-liberal social structure

Bernard D'Mello

2002-01-01

212

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

213

A LOOK BACK AT A LONG TERM TILLAGE EXPERIMENT AND A LOOK FORWARD AT THE POTENTIAL FOR SITE SPECIFIC TILLAGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

A tillage experimental area has been in place since 1976. Five tillage treatments (moldboard, chisel, till plant, slot plant, spring disk) were compared using randomized complete block design with four replications. Ten years of records (1991-2000) from the experimental area were examined for long ...

214

The Excavation Technology used in the Cow Catacombs of the Sacred Animal Necropolis, North Saqqara, Egypt  

Microsoft Academic Search

The technology used in tomb excavation in ancient Egypt has not been the subject of thorough investigation to date. A 'false end' in the catacombs of the mother of Apis bulls at the North Saqqara necropolis provides evidence of one excavation system used by tomb excavators. Chisel marks and 'cone' excavations elsewhere in the catacombs provide some evidence of an

Christopher J. Davey

215

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

ERIC Educational Resources Information Center

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

Belsky, Jay; de Haan, Michelle

2011-01-01

216

Updated: October 11, 2012 (Individual Presentations are Subject to Change) Forensics@NIST 2012 Symposium DRAFT AGENDA  

E-print Network

Firearms 1. "Mathematical Comparisons of Bullets and Cartridge Casings Using 2D and 3D Topography" by A, 2012 (Individual Presentations are Subject to Change) Page 2 2:00-2:20 Bullet Signature Identification Comparisons ­ Wei Chu 2:20-2:40 2D/3D Topography Comparisons of 10 Consecutively Manufactured Chisels

Perkins, Richard A.

217

26 ENGINEERING & SCIENCE SPRING 2013 hospitals, and learning how to use  

E-print Network

of the developing world-- lack of resources due to poverty. "Product design has always been the most interesting must be chiseled out by hand, causing pain and strain for the workers. Students engineer innovative pr together to find cheap, technological solutions for problems plaguing the rural populations in that Central

218

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; Blöthe, Marco; Roden, Eric

2012-01-01

219

Effects of injection systems and plastic mulches on distribution and emissions of cis- and trans-1,3-dichloropropene and chloropicrin.  

PubMed

The concentration and distribution of a soil fumigant in the subsurface of field plots are two key factors in the determination of the fumigant efficacy. Subsurface concentrations of the biologically active compounds cis- and trans-1,3-dichloropropene (1,3-D) and chloropicrin (CP) were determined in soil at two adjacent injection traces and midpoint between the two traces in plastic-covered field beds after injection of the fumigant Telone C35 by conventional chisels or by a coulter rig (Avenger coulters). Two of the four beds were covered with metallic polyethylene film (MPE) and the remaining two were covered with virtually impermeable film (VIF). Three hours after chisel injection, concentrations of the three compounds at the two adjacent injection traces in the two beds were highly variable. Large concentrations of the compounds were detected at the side traces, whereas the compounds were not detected at the middle traces (bed centers) in the two chisel-injected beds covered with MPE or VIF. Initial concentrations of the three compounds at the two adjacent injection traces in the two Avenger-coulter-injected beds were more uniform than in the chisel-injected beds but still variable. Also, the three compounds had diffused horizontally to midpoint between the two injection traces in all four beds, generally in smaller concentrations. Concentrations of the three compounds in the shallow subsurface soil layer (0.5-30 cm) in the beds became progressively more uniform and then declined slowly. Volatilization losses from the two Avenger-coulter-injected beds and the chisel-injected bed covered with VIF were low. Combination of Avenger coulter injection and VIF provided better retention of the compounds in this soil layer and, thus, likely would provide better fumigant efficacy and crop yield. PMID:17549542

Ou, Li-Tse; Thomas, John E; Allen, L Hartwell; Vu, Joseph C; Dickson, Donald W

2007-08-01

220

Soil erosion and agricultural sustainability  

PubMed Central

Data drawn from a global compilation of studies quantitatively confirm the long-articulated contention that erosion rates from conventionally plowed agricultural fields average 1–2 orders of magnitude greater than rates of soil production, erosion under native vegetation, and long-term geological erosion. The general equivalence of the latter indicates that, considered globally, hillslope soil production and erosion evolve to balance geologic and climate forcing, whereas conventional plow-based agriculture increases erosion rates enough to prove unsustainable. In contrast to how net soil erosion rates in conventionally plowed fields (?1 mm/yr) can erode through a typical hillslope soil profile over time scales comparable to the longevity of major civilizations, no-till agriculture produces erosion rates much closer to soil production rates and therefore could provide a foundation for sustainable agriculture. PMID:17686990

Montgomery, David R.

2007-01-01

221

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

222

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

223

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

224

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

225

Mortality of Mallards Exposed to Gamma Radiation Author(s): Richard L. Abraham  

E-print Network

)levels of 485 R, 715 R, and 894 R have been determined for green- winged teal (Anas crecca),blue-winged teal (Anas discors), and shovelers (Anas cly- peata) (1). The other study on waterfowl reports LDSO(O0)levels for one-year-old mallards(Anas platyrhynchos)of 650 R for x-radiation and 630 R for 60-Co, Gamma radiation

Minnesota, University of

226

Hydrogeology of the Piedmont Springs National Historic Site Grimes County, Texas  

E-print Network

Site relative to the economic lignite deposits Surface mining operation using a walking dragline and truck/shovel operation. . . . . . . . . Geologic Map of the Anderson- Millican area, (Star represents the location of Piedmont Springs National...) . . . . . . . . . . . 17 Major structural features of the northwest Gulf Coast Basin, (Ayers and Kaiser, 1986). . . . . . . 19 Hydrogeologic type in reclaimed surface lignite mines in Texas, (Mathewson et al. , 1982) . . . . . . . . 24 Recharge mechanisms of spoil...

Waclawczyk, Randy R.

1989-01-01

227

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

228

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

229

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

PubMed

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

Clark, Michael D

2011-01-01

230

Biomechanical modelling and evaluation of construction jobs for performance improvement.  

PubMed

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

Parida, Ratri; Ray, Pradip Kumar

2012-01-01

231

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

232

Analysis of diatomite sediments from a paleolake in central Mexico using PIXE, X-ray tomography and X-ray diffraction  

Microsoft Academic Search

Diatomite samples from paleolake Tlaxcala, in Central Mexico, have been analyzed using proton induced X-ray emission (PIXE), X-ray tomography and X-ray diffraction. Chiseled blocks were scanned with a 0.7 MeV proton beam, 0.1 mm in diameter, in 0.25 mm steps across the sediments. X-ray tomography with the same step sizes was then applied, in order to compare the concentrations obtained

J. Miranda; A. Oliver; G. Vilaclara; R. Rico-Montiel; V. M. Macías; J. L. Ruvalcaba; M. A. Zenteno

1994-01-01

233

Glossary of Construction Terms  

NSDL National Science Digital Library

Need to know what a cantilever is? Curious about screeding and Type II Moderate cement or cape chisels? Look no further than the Glossary of Construction Terms, provided by the National/California Contractor Referral and License Bureau. While by no means a definitive collection of construction terms, the glossary is fairly comprehensive in terms of the basics, offering short, clear explanations of tools, materials, and concepts. Topics include Carpentry, Concrete, Electrical, Heating and Air Conditioning, Painting, Plumbing, and Roofing, among others.

234

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

235

Application of stable isotope analysis to quantify the retention of eroded carbon in grass filters at the North Appalachian experimental watersheds  

Microsoft Academic Search

The entrapment of eroded soil organic carbon (SOC) in grass filters could affect watershed C export, but the magnitude of the process is rarely quantified. In order to assess the retention of eroded C in these settings, SOC stock was measured in grass buffers receiving runoff from cropped watersheds under long-term (>20 y): chisel-till (CT) corn (Zea mays, L.)-soybean [Glycine max,

P. A. Jacinthe; R. Lal; L. B. Owens

2009-01-01

236

Paint Scaler. Innovative Technology Summary Report  

SciTech Connect

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

None

2000-06-01

237

Carbon accumulation in cotton, sorghum, and underlying soil as influenced by tillage, cover crops, and nitrogen fertilization  

Microsoft Academic Search

Soil and crop management practices may influence biomass growth and yields of cotton (Gossypium hirsutum L.) and sorghum (Sorghum bicolorL.) and sequester significant amount of atmospheric CO2in plant biomass and underlying soil, thereby helping to mitigate the undesirable effects of global warming. This study examined the effects of three tillage practices [no-till (NT), strip till (ST), and chisel till (CT)],

U. M. Sainju; W. F. Whitehead; B. P. Singh

2005-01-01

238

Surface topography of the cylindrical gear tooth flanks after machining  

Microsoft Academic Search

The paper presents an analysis of three-dimensional surface topography of side and side out in tooth space flanks of cylindrical\\u000a gear machined after hobbing and chiselling by Fellows method. The parameters and functions of surface topography as well as\\u000a spectral analysis were used. Primary surface topography after extraction of involute tooth profile was analysed. It was found\\u000a that contour maps

Jacek Michalski

2009-01-01

239

Powers of the Facsimile: A Turing Test on Science and  

E-print Network

real enough? When would approximation suffice? Plowing the Dark What is a realist style? Not a realism based on "matters of fact," but a realism involved in the deployment of what I have called "matters Heidegger has proposed to call "things". And yet it seems that the model for sturdy realism has remained

Boyer, Edmond

240

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

241

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...

242

Ready for Action  

USGS Multimedia Gallery

This photo shows a snow plow and road salt application truck that is used to clear snow and ice from roadways for improving traffic and pedestrian safety. The use of salt to deice pavement can be harmful to aquatic life in urban streams. The USGS is involved in studies that focus on the influence of...

243

Durability of Drainage Improvement by Combination of Main Drain and Trench Drains with Vertical Drains in Clayey Field Converted from Paddy to Upland Use  

NASA Astrophysics Data System (ADS)

The drainage efficiency of a subsurface drainage system for avoidance of standing water on the plow pan of clayey field was evaluated. A subsurface drainage system with a main drain and orthogonally adjoined rice husk trench drains joined by vertical rice husk drains was constructed on a test plot and compared to an identical control plot of paddy field converted to upland use under soybean cultivation. The ratio of total underdrain discharge to rainfall in the improved plot greatly increased over two years compared to that in a control plot. In the improved plot, the peak underdrain discharge per hour associated with some heavy rainfalls was around 3 mm/h in the first year but decreased to about 2 mm/h in the second year. By improving drainage in the paddy field, standing water on the plow pan was quickly eliminated after rain events and the period of flooding on the plow pan during the soybean growing season was greatly reduced. However, underdrain discharge in the improved plot decreased greatly in the third year to be at the same level as in the control plot, and rain water flooded the plow pan for extended periods of time.

Adachi, Kazuhide; Ohno, Satoshi; Furuhata, Masami; Ogura, Chikara; Tanimoto, Takeshi

244

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

245

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

246

Dimensionless Performance Model for Gas-Fed Pulsed Plasma J.K. Ziemer  

E-print Network

, capacitor, and resistor are placed in series to represent the moving discharge as an LCR circuit. The elements of this circuit are generally variable with the inductance change resulting from the cur- rent sheet motion. The circuit model coupled with a "snow-plow" mass accumulation description provide

Choueiri, Edgar

247

Snow and Ice Field Handbook for Snowplow Operators  

E-print Network

Minnesota Snow and Ice Control Field Handbook for Snowplow Operators Second Revision Manual Number to the plow operators who keep our roads safe all winter long. It is based on the Manual of Practice Graphic Design: Cadie Wright Adhikary, CTS Acknowledgments #12;Contents Basic Concepts

Minnesota, University of

248

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

249

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

ERIC Educational Resources Information Center

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

Kelderman, Eric

2012-01-01

250

Impacts of Historical Land Use on Soil Nitrogen Cycles in Falmouth, MA and the Threat of Chronic N Amendment Demonstrated at the  

E-print Network

Impacts of Historical Land Use on Soil Nitrogen Cycles in Falmouth, MA and the Threat of Chronic N is an important aspect of soil nitrogen cycling. Historic agriculture land use and modern atmospheric nitrogen deposition both impact soil nitrogen cycles. To evaluate agricultural land use I compared plowed fields

Vallino, Joseph J.

251

PolicyBlocks: An Algorithm for Creating Useful Macro-Actions in Reinforcement Learning  

E-print Network

learns a set of skills (snow- plow, hockey stop) that are useful for several di#11;erent ski runs. One that have identical structure, but with di#11;er- ent goals. For example, in Dietterich's Taxi domain, and many useful options found by our algorithm have no clearly de#12;ned sub- goal. Bowling and Veloso

Massachusetts at Amherst, University of

252

WATER AND SOLUTE TRANSPORT IN A CULTIVATED SILT LOAM SOIL: 2. NUMERICAL ANALYSIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A field experiment was performed to study the effects of soil structure heterogeneity generated by farming practices (i.e., compaction by wheel traffic, plowing, surface tillage) on plot-scale water flow and solute transport. The experiment involved a 4m by 2 m field plot that was uniformly sprinkle...

253

The influence of long-term tillage systems on symbiotic N 2 fixation of pea ( Pisum sativum L.) and red clover ( Trifolium pratense L.)  

Microsoft Academic Search

Pea as a grain legume and red clover as a forage legume in the seeding year were cultivated in two long-term differentiated tillage systems on a loess soil in Germany. A continuous conventional tillage system (plow; CT) and a continuous minimum tillage system (rotary harrow; MT) were established in 1970. With pea and red clover dry matter accumulation and N

Karin Reiter; Knut Schmidtke; Rolf Rauber

2002-01-01

254

Where does Strip Tillage Fit in Montana and Wyoming Sugarbeet Production  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

255

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

256

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

257

Winter Maintenance Guidelines for Porous Asphalt Maintenance  

E-print Network

Winter Maintenance Guidelines for Porous Asphalt General Maintenance · Plow after every storm · Up to ~75% net salt reductions for porous asphalt have been documented. USE SALT REDUCTION NUMBERS Asphalt Pavement Association (PAPA) Porous Asphalt Pavements Guide: http://www.pahotmix.org/PDF/porous1

258

About Resources Archives Events Contact Submit No. 10 : Fall/Winter 2001  

E-print Network

About Resources Archives Events Contact Submit No. 10 : Fall/Winter 2001 Home Columns Poetry Essays, if I wanted to give it a try. I had walked Bob and Stormy on the ground before, but driving them on Tina, as she was more entangled than me. But the plow was a feather weight in the horses' forward force

Nekola, Jeffrey C.

259

Fungal colonization of aspen roots following mechanical site preparation  

Microsoft Academic Search

Fungal colonization of aspen (Populus tremuloides Michx.) roots was examined in boreal mixedwood sites that were mechanically site prepared 8-10 years earlier for white spruce (Picea glauca (Moench) Voss) regeneration using disc trenchers or ripper plows. A survey of root wounds determined that Armillaria sinapina Bérubé & Dessureault and Armillaria ostoyae (Romagn.) Herink were both wound pathogens of aspen; however,

J. M. Pankuch; P. V. Blenis; V. J. Lieffers; K. I. Mallett

2003-01-01

260

Electric Driven Heat Pumps in Distillation Processes  

E-print Network

.0 6.0 .70 1 0 2.0 '.0 STE'""l-..1 VALUE IN DOLLARS PER MILLION BTU Figure 6. Pentane-Isopentane Splitter Economic Summary ilOOO/Yll To tal Prelont Annnal Val ue C...h Plow Calb Flow 408. 408. 1.026.003 993. 1.284+003 1.061+003 1...

Harris, G. E.

1983-01-01

261

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

262

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...

263

Black Soldier Fly (Diptera: Stratiomyidae) Colonization of Pig Carrion in South Georgia  

Microsoft Academic Search

The black soldier fly, Hermetia illucens (L.), is thought to colonize corpses 20-30 days postmortem. However, recent observations indicate this might not be true for all cases. Therefore, we conducted a study examining colonization by the black soldier fly and other Diptera on pig carrion in a plowed field in southern Georgia from 20 September through 21 February. Our data

Jeffery K. Tomberlin; D. Craig Sheppard; John A. Joyce

2005-01-01

264

29 CFR 1915.118 - Tables.  

Code of Federal Regulations, 2011 CFR

... 3.6 6.2 5.1 3.6 Table G-2—Rated Capacities for Improved Plow Steel, Independent Wire Rope Core, Wire Rope and Wire Rope Slings [In tons of 2,000 pounds] Rope diameter Single leg Vertical A B C Choker...

2011-07-01

265

29 CFR 1915.118 - Tables.  

Code of Federal Regulations, 2010 CFR

... 3.6 6.2 5.1 3.6 Table G-2—Rated Capacities for Improved Plow Steel, Independent Wire Rope Core, Wire Rope and Wire Rope Slings [In tons of 2,000 pounds] Rope diameter Single leg Vertical A B C Choker...

2010-07-01

266

29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)  

Code of Federal Regulations, 2011 CFR

...recommendations are not available. Table 1—Wire Rope Clips Improved plow steel, rope... 21/4 (5.7) 21.2 Wire Rope Table—Rate Loads for Single...slings shall also be considered. Wire Rope Table—Rated Loads for...

2011-07-01

267

29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)  

Code of Federal Regulations, 2013 CFR

...recommendations are not available. Table 1—Wire Rope Clips Improved plow steel, rope... 21/4 (5.7) 21.2 Wire Rope Table—Rate Loads for Single...slings shall also be considered. Wire Rope Table—Rated Loads for...

2013-07-01

268

29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)  

...recommendations are not available. Table 1—Wire Rope Clips Improved plow steel, rope... 21/4 (5.7) 21.2 Wire Rope Table—Rate Loads for Single...slings shall also be considered. Wire Rope Table—Rated Loads for...

2014-07-01

269

29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)  

Code of Federal Regulations, 2012 CFR

...recommendations are not available. Table 1—Wire Rope Clips Improved plow steel, rope... 21/4 (5.7) 21.2 Wire Rope Table—Rate Loads for Single...slings shall also be considered. Wire Rope Table—Rated Loads for...

2012-07-01

270

29 CFR 1915.112 - Ropes, chains and slings.  

Code of Federal Regulations, 2010 CFR

...of not less than five (5) is maintained. (b) Wire rope and wire rope slings. (1) Tables G-2 through G-5 in...various sizes and classifications of improved plow steel wire rope and wire rope slings with various types of...

2010-07-01

271

The Construction of Equipment for Hilling-up and Taking-out Soil Around Grafted Grapevines  

E-print Network

that the commercially available Weed Badger unit has several desirable features for removing the ridge of soil along Station for financial support that made this work possible. Hilling or ridging of soil under the trellis in turn, feeding the third, and the third plow actually creating the ridge of soil under the trellis. See

272

Florida Vegetable Gardening Guide1 Sydney Park Brown, J.M. Stephens, Danielle Treadwell, Susan Webb, Amanda Gevens, R.A.  

E-print Network

, but it is usually worthwhile to improve the garden plot with additions of organic matter (see below). Spade or plowSP 103 Florida Vegetable Gardening Guide1 Sydney Park Brown, J.M. Stephens, Danielle Treadwell Sciences Department, and organic farming specialist; Susan Webb, associate professor, Entomology

Watson, Craig A.

273

Effects of emergence time on survival and growth in an early old-field plant community  

Microsoft Academic Search

The time at which plants emerge from the soil is shown to be correlated with both survival and growth in each of four years in a plant community emerging after yearly plowing. For all seven species investigated, earlier emerging individuals generally had both a higher biomass and probability of survival. There were differences among species in the effect of emergence

T. E. Miller; W. K. Kellogg

1987-01-01

274

Arsenic Fate And Transport In Red Cove, Fort Devens  

EPA Science Inventory

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

275

77 FR 15802 - Notice of Inventory Completion: Central Washington University Department of Anthropology...  

Federal Register 2010, 2011, 2012, 2013

...inadvertently uncovered at least 27 human skeletons while plowing his...affiliation. However, the human remains have markings of 19-15...oral tradition indicate that ancestors of the present day Confederated...U.S.C. 3001(9), the human remains described in this...

2012-03-16

276

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

277

Two Centuries of Soil Conservation.  

ERIC Educational Resources Information Center

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

Helms, Douglas

1991-01-01

278

N E W S AN D V I E W S NATURE MEDICINE VOLUME 13 | NUMBER 3 | MARCH 2007 253  

E-print Network

­377 (2005). A plague upon fibrin Richard W Titball & Petra C F Oyston A surface protease helps Yersinia pestis plow its way through the body during pneumonic plague. The authors are in the Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK. e-mail: rwtitball@mail.dstl.gov.uk Bubonic plague

Cai, Long

279

FINAL TECHNICAL REPORT Project Title: Environmental Impacts of Wind Power Development on the Population Biology  

E-print Network

University, Manhattan, Kansas 66506, plowe@ksu.edu, 785 532-6804 Other Project Team Members Samantha M, Manhattan, Kansas 66506, lmhunt@k-state.edu, 785-532-6653 Project Oversight from National Wind Coordinatingi FINAL TECHNICAL REPORT Project Title: Environmental Impacts of Wind Power Development

Sandercock, Brett K.

280

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

281

(Lab Use Only) Before Last  

E-print Network

2 3 Check Test Requested (plow layer sample) $15 $7 $12 $7 $7 $16 $7 $7 Nitrate Before selecting this test please read the section on nitrate on the BACK SIDE Sampling to 24" is required for this test Clover CORN LEGUMES Corn, Grain Corn, Silage Sweet Corn ton/acre ton/acre ton/acre ton/acre ton/acre ton

Ciocan-Fontanine, Ionut

282

Nitrogen  

Microsoft Academic Search

Studies were conducted on two Blackland Prairie soils at Dallas, TX to determine the influence of clover plowed under on N nutrition of subsequent crops. Wheat yields were 103 and 86% of the yields obtained with 90 kg N\\/ha for the first and second crops after clover, respectively. Yields of nonfertilized wheat following fallow were 75 and 72% of the

Billy W. Hipp

1987-01-01

283

Reclaiming freshwater sustainability in the Cadillac Desert  

E-print Network

the plow." Early stewards of freshwater resources--like John Wesley Powell-- warned that the American WestReclaiming freshwater sustainability in the Cadillac Desert John L. Saboa,1 , Tushar Sinhaa,2 , Laura C. Bowlingb , Gerrit H. W. Schoupsc , Wesley W. Wallenderd,e , Michael E. Campanaf , Keith A

Sinha, Tushar

284

Santa Rosa Wetlands .. .................................1  

E-print Network

comes up in broad-area seeps that cause most of the soils to be saturated to the surface or root-zone wetlands are in danger of eventually disappearing. Many acres of cienega habitat have been ditched, plowed and water passing through the soluble layers comes to the surface in the sink creat- ing numerous seeps

Johnson, Eric E.

285

Effects of tillage and winter cover cropping on microbial substrate-induced respiration and soil aggregation in two Japanese fields  

Microsoft Academic Search

We hypothesized that cover cropping could increase soil microbial activities under various tillage systems and that increased microbial activities would improve soil properties. Soil sampling was conducted at two fields in Japan in 2009. At the Ibaraki field (Andosol, clay loam), three tillage practices (no-tillage, plowing to 30?cm, and rotary tillage to 15?cm) and three types of winter cover cropping

Tomomi Nakamoto; Masakazu Komatsuzaki; Toshiyuki Hirata; Hajime Araki

2012-01-01

286

Soil physical responses to cattle grazing cover crops under conventional and no tillage in the Southern Piedmont USA  

Microsoft Academic Search

Grazing of cover crops in grain cropping systems can increase economic return and diversify agricultural production systems, but the environmental consequences of this intensified management have not been well documented, especially under different tillage systems. We conducted a multiple-year investigation of how cover crop management (grazed and ungrazed) and tillage system [conventional (CT; initial moldboard plowing and thereafter disk tillage)

Alan J. Franzluebbers; John A. Stuedemann

2008-01-01

287

Martha A. Hartmans & Edgar L. Michalson the Economic & Environmental Impacts of  

E-print Network

, contour plowing, or contour strip cropping to reduce erosion (Carlson et al., 1994). Crop residues are rou and federal laws. #12;3 SOIL EROSION The Palouse region includes over two million acres of rich agricultural land in northern Idaho and eastern Washington. The area has dune-shaped, steeply rolling hills covered

O'Laughlin, Jay

288

Soil Science Society of America Journal Soil Sci. Soc. Am. J.  

E-print Network

indicative of slowly reversible and irreversible reactions. A snow-plow effect was also observed where Pb, and plants, respectively, (USEPA, 2005). Lead enters the soil through natural processes such as weathering) and subsurface (10­20 cm) soils, respective- ly were reported for areas in the vicinity of industrial plants

Sparks, Donald L.

289

Depth-Independent Drag Force Induced by Stirring in Granular Media Francois Guillard,* Yoel Forterre,  

E-print Network

systematically study how the saturated drag force scales with the control parameters and show that this effect plowing [5]), in geo- physical problems, for example, for the design of snow obstacles [6] or plant-soil interactions [8]. Experimentally, different configurations have been studied. A first

Boyer, Edmond

290

Boundary layer response to wind gusts  

E-print Network

Souadary- Layer Oscillstioas and Transition on a Plat Plate. " NACA Report 909. 2. pailer, c. E. ) sErperlaental Heat 'Transfer snd soundary Layer Sehavior uith 100 c. P. s. Plow Oscll, lstions. RASA TH S-2521. 3. Noore, p, K. and Ostrach, S...

Morland, Bruce Thomas

1968-01-01

291

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...

292

Shear strength properties of wet granular materials Vincent Richefeu,  

E-print Network

effects appear only at low confining pressures, e.g. in surface soils. It is a common observation that, when plowing a wet granular soil, large cohesive aggre- gates are formed. The largest capillary]. Although capillary phenomena at the interface be- tween two solid bodies are well understood, it is much

Paris-Sud XI, Université de

293

A' Brief. History of the Tower Shielding Facility and Tower Shielding Facility  

E-print Network

A' Brief. History of the Tower Shielding Facility and Programs Tower Shielding Facility Hoisting of radiation from reactor. 0 Guyed steel structure 315 feet high 0 Conform to AISC specifications for steel 200 fl with 80 mph wind 0 Two-inch plow steel guys (16) stressed to 75,000 lbs each to minimize tower

294

Impact of Tillage and Residue Burning on Carbon Dioxide Flux in a Wheat–Soybean Production System  

Microsoft Academic Search

Burning of wheat (Triticum aestivum L.) residue followed by plowing is a common management practice in wheat-soybean (Glycine Max (L.) Merrill) production systems in the mid-southern USA. However, this residue management practice is not environmen- tally friendly and may not be sustainable. The objectives of this study were to (i) evaluate the effects of N fertilization of wheat, residue burning,

Kristofor R. Brye; David E. Longer; Edward E. Gbur

2006-01-01

295

Ephemeral Gullies: To Till or Not to Till?  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

296

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.

297

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

298

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

299

[Cardiovascular assessment in building activities using an ergospirometer].  

PubMed

We report preliminary results of a current study aimed to evaluated peak oxygen consumption and others cardiopulmonary exercise test parameters, in some common and tiring building activities, with the use of a portable ergospirometer stress test (Metamax 3B, Cortex Biophysik). We tested 3 Building School's Teachers of Seriate (Bergamo): the materials handling and transport of cement bricks and to dig with pick and shovel reaches peak anaerobic threshold into few minutes while the activity of make molter permits an aerobic metabolism in all building workers tested. PMID:14979167

Bigoni, F; Borleri, D; Seghizzi, P; Mosconi, G

2003-01-01

300

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

ScienceCinema

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

2013-05-29

301

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

E-print Network

, types of furrow openers, press wheels, planting at variable depths, and the treatment, of undelinted seed and delintecl seed with Ceresan, lime, and sulfur. All the experiments with planter attachments were conducted at the Main Station Farm... soil out of the furrow until the seed reached the bottom of the furrow, gave better resu1t.s than a wide shovel four inches in width. The regular open center press wheel used after covering the seed and in combination with a knife opener gave a...

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

1942-01-01

302

Oral characteristics of a patient with Ekman-Westborg-Julin trait: a case history.  

PubMed

This article presents the case of a Japanese woman who had Ekman-Westborg-Julin trait. She had general macrodontia with multituberculism, evagination of the premolar, single conical roots, shovel-shaped incisors, enamel hypoplasia, impacted tooth, dental crowding, and an open bite. The oral and general characteristics of this patient are described and include the histological and radiographic findings of the mandibular third molars. We suggest that the distinctive oral features with macrodontia of the permanent teeth, multituberculism, evagination, single conical roots, and impaction of the tooth could be defined as the Ekman-Westborg-Julin trait. PMID:22416990

Komatsu, Tomoko; Kurihara, Tae; Ito, Yumi; Lee, Masaichi-Chang-Il; Miyagi, Atsushi; Ikeda, Masakazu

2012-03-01

303

Tillage system, application rate, and extreme event effects on herbicide losses in surface runoff.  

PubMed

Conservation tillage can reduce soil loss; however, the residual herbicides normally used to control weeds are often detected in surface runoff at high levels, particularly if runoff-producing storms occur shortly after application. Therefore, we measured losses of alachlor, atrazine, linuron, and metribuzin from seven small (0.45-0.79-ha) watersheds for 9 yr (1993-2001) to investigate whether a reduced-input system for corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] production with light disking, cultivation, and half-rate herbicide applications could reduce losses compared with chisel and no-till. As a percentage of application, annual losses were highest for all herbicides for no-till and similar for chisel and reduced-input. Atrazine was the most frequently detected herbicide and yearly flow-weighted concentrations exceeded the drinking water standard of 3 microg L(-1) in 20 out of 27 watershed years that it was applied. Averaged for 9 corn yr, yearly flow-weighted atrazine concentrations were 26.3, 9.6, and 8.3 microg L(-1) for no-till, chisel, and reduced-input, respectively. Similarly, flow-weighted concentrations of alachlor exceeded the drinking water standard of 2 microg L(-1) in 23 out of 54 application years and in all treatments. Thus, while banding and half-rate applications as part of a reduced-input management practice reduced herbicide loss, concentrations of some herbicides may still be a concern. For all watersheds, 60 to 99% of herbicide loss was due to the five largest transport events during the 9-yr period. Thus, regardless of tillage practice, a small number of runoff events, usually shortly after herbicide application, dominated herbicide transport. PMID:17071888

Shipitalo, Martin J; Owens, Lloyd B

2006-01-01

304

Comparing soil surface roughness patterns at different colour and organic matter conditions using shadow analysis method  

NASA Astrophysics Data System (ADS)

The method based on the shadow analysis has shown to be one of the most convenient techniques to characterize SSR in the field when used in arid and semi-arid regions. However, the technique has not been proved with soils having more than 3% of organic matter and soil with very dark colours. In order to proof that the technique is able to function at field trials with soils richer in organic matter and with different colours, the project compared SSR resulting in 5 different types of soils after passing chisel. The main variation amongst the soils was the colour, brown soils, grey pale soils and yellow soils and the organic matter associated, 1 to 6%. All the plots measured 1m2 and were used for crop production. For each site 6 plots were considered and all the data was captured during summer time to avoid the influence of rain. The SSR obtained varied from 44 to 62% showing that the results were not significantly related to the darkness of colour and the content of organic matter. The variations were strongly related to the amount of clay found on different soils. This difference could be introduced by the difficulty in some cases to pass the chisel when soil is too dried since the acquisition of field data was done after chisel tool was passed on different sites. The parameters demonstrated that the method can be used to study the influence of wind and water erosion on soil surface at field conditions with independence of colour and organic matter properties.

García Moreno, R.; Diaz Alvarez, M. C.; Saa Requejo, A.; Guerrero López, F.

2012-04-01

305

Is the obturator artery safe when performing ischial osteotomy during periacetabular osteotomy?  

PubMed

The purposes of this study were (1) to evaluate the actual distance between the obturator artery and the ischial osteotomy site when performing periacetabular osteotomy via an anterior approach and (2) to determine a safe method to avoid injuring the obturator artery during this procedure. Twenty-nine hemipelves from cadavers were used in this study. The mean distance between the obturator artery and the ischial osteotomy site was 35.6 ± 7.5 mm and always exceeded 20 mm. Therefore, the procedure can be performed safely when a chisel blade of 20 mm or shorter is used. PMID:20556381

Kamada, Satoshi; Naito, Masatoshi; Shiramizu, Kei; Nakamura, Yoshinari; Kinoshita, Koichi

2011-04-01

306

A Journey Around the World Mind  

E-print Network

, are by far the oldest items in the Library. Heat was applied to hollows chiselled out on the reverse of specially prepared ox scapulae and turtle shells and this produced characteristic cracks. The cracks were then interpreted as answers to questions that had... of such Copies During the Times Therein Mentioned confirmed the Library’s status. It gave publishers copyright protection on certain conditions – one being that they had to send copies of their books to a number of privileged libraries, Cambridge among them...

Cambridge University Library; Fox, Peter; Jenkins, Brian

2010-01-01

307

The Holmesian Federation Issue 6  

E-print Network

they were standing on a grassy swath in a clearing. G' with dense jungle on blue Siren hyacinths porcelain-blue tropical the sun was fully up. the trees. ~ ';\\5r------ one side and a lake covered with red and on the other. Overhead was a pale sky... of steel set on smooth shafts of jet black wood, finely honed edges catching the lamplight. At their sides yard-long swords in sheaths of black enamel and silver. basket hilts were of chiselled gold with inlayed red, green, blue enamel. The egg...

Multiple Contributors

1985-01-01

308

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

NASA Technical Reports Server (NTRS)

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

Miyoshi, K.; Buckley, D. H.

1977-01-01

309

Friction and fracture of single-crystal silicon carbide in contact with itself and titanium  

NASA Technical Reports Server (NTRS)

An investigation was conducted to examine the friction properties and mechanical behavior of single-crystal silicon carbide (0001) surface sliding against itself and against polycrystalline titanium. The results indicate hexagon-shaped pits of silicon carbide and the formation of platelet hexagon-shaped wear debris of silicon carbide due to cleavages of both prismatic and basal planes as a result of silicon carbide sliding against itself. The fracturing of silicon carbide also occurs near the adhesive bond to titanium. The wear debris produced by brittle fracture plows the titanium and transfers to it. Further, the silicon carbide wear debris, which adhered and transferred to titanium, plows the silicon carbide surface and transfers back to it

Miyoshi, K.; Buckley, D. H.

1979-01-01

310

What Are Your Forages Worth? Troy Downing, Anna-Marie Chamberlain, Mike Gamroth, and Amy Peters  

E-print Network

Your farm Planting plowing $50/hr 1 hr 50.00 rototill 2x $85/hr 1 hr 85.00 discing 2x $50/hr 1 hr 50.00 rolling & cultipacking $50/hr 1 hr 50.00 Seeding $50/hr 1 hr 50.00 fertilizer $500/ton 250 lb 62.50 fert totals $431.25/acre Prorated costs per year (over 5 years) $ 86.25/year Table 2. Typical per-acre annual

311

Charlotte County 4-H Clubs T.hink A.ct G.row  

E-print Network

Charlotte County 4-H Clubs T.hink A.ct G.row Revised August 2014 Cows'n Plows Ages 8-18 as of September 1, 2014 Projects include cattle, hogs, and sheep. Club meets 2nd Tuesday of each month, 6:30 pm-637-0821 Or Jackie Andrews at 941-628-6815 Manes' n Reins 4-H Horse Club Ages 8 to 18, as of September 1, 2014 Horse

Watson, Craig A.

312

Conservation tillage induced changes in organic carbon, total nitrogen and available phosphorus in a semi-arid alkaline subtropical soil  

Microsoft Academic Search

A multi-year experiment was conducted to compare the effects of conservation tillage (no-till and ridge-till) with conventional plow tillage on organic C, N, and resin-extractable P in an alkaline semi-arid subtropical soil (Hidalgo sandy clay loam, a fine-loamy, mixed, hyperthermic Typic Calciustoll) at Weslaco, TX (26°9?N 97°57?W). Tillage comparisons were established on irrigated plots in 1992 as a randomized block

L. M Zibilske; J. M Bradford; J. R Smart

2002-01-01

313

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

314

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

315

Surface Roughness Parameter Uncertainties on Radar Based Soil Moisture Retrievals  

NASA Technical Reports Server (NTRS)

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

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

2012-01-01

316

Climate Change: Natural Water and Fertilization Effects on Winter Rye (Secale cereale L.) Yield in Monoculture  

Microsoft Academic Search

Interaction of rainfall on crop fertilization factors, such as macronutrients and yield, were studied during a long-term field experiment on a calcareous sandy soil with a low humus content in north Hungary at Örbottyán Experimental Station of RISSAC-HAS from 1961 to 2004. When the experiment was commenced (1959) the plowed portion of experimental soil (top soil) had a pH (H2O)

2009-01-01

317

Origin and properties of humus in the subsoil of irrigated rice paddies  

Microsoft Academic Search

To examine the effect of downward percolation of flooding water under reduced soil conditions on the binding type of humus in the plow layer soil of paddy fields, a model experiment was conducted. Changes in the binding type of humus were analyzed by successive extraction of humus with water, 0.25 m Na2SO4, 0.1 m Na4P207 (pH 7.0), 0.1 m Na4P207

Nagamitsu Maie; Akira Watanabe; Makoto Kimura

2001-01-01

318

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

319

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

320

Particle-facilitated pesticide leaching from differently structured soil monoliths.  

PubMed

The leaching of soil particles and surface applied 14C-labeled glyphosate and pendimethalin from intact soil columns (height: 50 cm; diameter: 30 cm) were investigated, and the relative significance of particle-facilitated pesticide transport was quantified. Investigations were performed with a recently plowed (four columns) and an untilled (five columns) sandy loam soil. Leaching was driven by three irrigation events (15 mm h(-1); 2 h each). Samples of the leachate were filtered immediately (within 1.5 minutes) using 20 nm filters, and the 14C-pesticide content was determined for filtered and unfiltered samples. Pesticide leaching was driven by preferential water flow in macropores. For the plowed structure, 68+/-10% of the leached glyphosate (average of 6 events+/-std.) was bound to particles whereas significantly less glyphosate was bound to particles in leachate from minimally disturbed columns (17+/-12%). Thus, the results suggest that soil structure affected the mode of transport of glyphosate. It is likely that glyphosate sorbed strongly when applied on recently plowed soil (Kd=503 L kg(-1) for the soil), and that it could be mobilized and transported independently of soil particles more easily when applied on the minimally disturbed soil covered in part with crop residues (Kd<1 L kg(-1) for straw). Significantly less amounts of soil particles were leached from minimally disturbed (119-247 mg) than from recently plowed (441-731 mg) columns. The significance of particle-facilitated pendimethalin leaching could not be accurately quantified due to disagreement between control measurements based on both 14C-activity and chemical analyses. PMID:19875794

Gjettermann, B; Petersen, C T; Koch, C B; Spliid, N H; Grøn, C; Baun, D L; Styczen, M

2009-01-01

321

BotEC: The Himalayas and Continental Drift  

NSDL National Science Digital Library

Queston: The story of the Himalayas can be traced back to the breakup of the supercontinent, called Pangaea, about 200 million years ago, when India began its rapid movement northward towards Asia. Asia was a much smaller continent then. Then, between 45 and 55 million years ago, India and Asia collided. Before collision, India moved northward at about 7-10 centimeters per year. Remarkably, India's northward movement was slowed only a little after the collisionâit continues to plow into Asia at a rate of 5-6 centimeters per year. We can measure the present northward movement of India into Asia using GPS measurements over a period of time. So, there is little doubt of the continued movement of India. There is much debate about how the northward march of India into Asia is being accommodated. Of course, the high Himalayan Plateau is a manifestation of this collision between two continents. Let's assume that India began to plow into the Asian continent 55 million years ago and that, since then, it has continued to uniformly move northward into the Asian continent at 6 centimeters per year (for 55 million years). Calculate the total distance (in kilometers) that India has plowed into Asia.

Kresan, Peter

322

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

323

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.; Savenije1, H. H. G.

2012-01-01

324

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

USGS Publications Warehouse

Harvested rice fields provide critical foraging habitat for wintering waterfowl in North America, but their value depends upon post-harvest treatments. We visited harvested ricefields in the Sacramento Valley, California, during the winters of 2007 and 2008 (recent period) and recorded their observed status as harvested (standing or mechanically modified stubble), burned, plowed, or flooded. We compared these data with those from identical studies conducted during the 1980s (early period). We documented substantial changes in field status between periods. First, the area of flooded rice increased 4-5-fold, from about 15% to >40% of fields, because of a 3-4-fold increase in the percentage of fields flooded coupled with a 37-41% increase in the area of rice produced. Concurrently, the area of plowed fields increased from 35% of fields, burned fields declined from about 40% to 1%, and fields categorized as harvested declined from 22-54% to <15%. The increased flooding has likely increased access to food resources for wintering waterfowl, but this benefit may not be available to some goose species, and may be at least partially countered by the increase of plowed fields, especially those left dry, and the decrease of fields left as harvested.We encourage waterfowl managers to implement a rice field status survey in the Sacramento Valley and other North American rice growing regions as appropriate to support long-term monitoring programs and wetland habitat conservation planning for wintering waterfowl.

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

2010-01-01

325

Toxoplasma gondii in waterfowl: the first detection of this parasite in Anas crecca and Anas clypeata from Italy.  

PubMed

Understanding the spread of Toxoplasma gondii in waterfowl is of interest for elucidating the potential involvement of these birds in maintaining the parasitic life cycle because birds are exposed to these parasites. Sera from 103 adult, free-range game birds, representing 13 different species living in the Italian wetlands, were examined using modified agglutination tests for antibodies specific to T. gondii . In seropositive birds, the brain and heart were homogenized and DNA was extracted to perform nested polymerase chain reaction (nPCR) and genotyping. Out of the 103 serum samples, 9 (8.7%) were scored as positive with titers ranging from 1/20 to 1/160. The seropositive animals corresponded to 4 of the species: Anas platyrhynchos (mallard; 2/17), Anas clypeata (northern shoveller; 2/11), Anas crecca (common teal; 3/41), and Gallinago gallinago (common snipe; 2/8). Parasite DNA was detected in 3 out of 9 brain samples, while the PCR results from the heart specimens were negative in all of the birds. The occurrence of non-clonal types of T. gondii was suggested in all cases. In conclusion, we describe the first documented detection of DNA of T. gondii in tissues from the northern shoveller and common teal, thereby extending the range of intermediate hosts for this parasite. PMID:23145510

Mancianti, Francesca; Nardoni, Simona; Mugnaini, Linda; Poli, Alessandro

2013-06-01

326

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

SciTech Connect

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

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

1993-08-01

327

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

328

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

329

Effects of application methods and plastic covers on distribution of cis- and trans-1,3-dichloropropene and chloropicrin in root zone.  

PubMed

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

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

2005-12-01

330

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

USGS Publications Warehouse

1. We used up to 34 years of capture-recapture data from about 22,100 new releases of day-old female ducklings and multistate modelling to test predictions about the influence of environmental, habitat and management factors on natal dispersal probability of three species of ducks within the Engure Marsh, Latvia. 2. The mean natal dispersal distances were very similar (c . 0?6-0?7 km) for all three species and were on average 2?7 times greater than breeding dispersal distances recorded within the same study system. 3. We were unable to confirm the kinship hypothesis and found no evidence that young first-nesting females nested closer to their relatives (either mother or sister) than to the natal nest. 4. Young female northern shovelers, like adults, moved from small islands to the large island when water level was high and vice versa when water level was low before the construction of elevated small islands. Movement probabilities between the two strata were much higher for young shovelers than adults, suggesting that young birds had not yet developed strong fidelity to the natal site. Movements of young female tufted ducks, unlike those of shovelers, were not dependent on water level fluctuations and reflected substantial flexibility in choice of first nesting sites. 5. Data for young birds supported our earlier conclusion that common pochard nesting habitats in black-headed gull colonies were saturated during the entire study period. Young females, like the two adult age groups, moved into and out of colonies with similar probability. Fidelity probability of female pochards to each stratum increased with age, being the lowest (0?62) for young (DK) females, intermediate (0?78) for yearlings (SY) and the highest (0?84) for adult (ASY) females. 6. Young female tufted ducks, like adults, showed higher probabilities of moving from islands to emergent marshes when water levels were higher both before and after habitat management. The relationship between the spring water levels and movement was much weaker for young females than for adults. 7. Young female diving ducks exhibited much stronger (compared to adults) asymmetric movement with respect to proximity to water, with higher movement probabilities to near-water locations than away from these locations. 8. Local survival of day-old ducklings during the first year of life was time-specific and very low (means for different strata/states 0?01-0?08) because of high rates of emigration and prefledging mortality.

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

2003-01-01

331

The Use of Soil in Criminal Investigations  

NASA Astrophysics Data System (ADS)

Forensic soil science, as a newly developed discipline of soil science, has matured to the extent that well-defined questions and successful crime scene investigations are being addressed in increasingly refined ways to assist law enforcement agencies. Soils, rocks, regolith, minerals and man-made mineral particles such as bricks (i.e. referred to "human-made" soil materials) are being used in specialised forensic investigations to associate/disassociate a sample taken from an item, such as shoes, clothing, shovel or vehicle, with a specific location. The majority of forensic cases involving soil materials are usually overwhelmingly complex, and the challenges of associating relevant information from one source with another, often requires the use and development of sophisticated field and laboratory methods. Through examples from case studies, this presentation will demonstrate how advanced field and laboratory approaches have been critical in developing coherent, predictive, soil models, from landscape to microscopic scales, to help contribute to soil-based criminal investigations in both Australia and Scotland. To demonstrate the critical importance of soil materials in forensic investigations, the following 2 case studies, which tackle difficult problems at a range of scales involving highly complex issues, will be presented: •The use of soil evidence to help solve a double murder case. This investigation used morphological, chemical, physical and mineralogical properties to identify similarities between soil-regolith found on a shovel taken from the suspect's vehicle and wetland soil-regolith subsequently located in the bottom of a quarry (Fitzpatrick and Raven, 2012). •The use of soil and related material to help search and to provide evidence in a murder case. This investigation used soil mineralogical and organic properties to identify similarities between sand found on a shovel and sand subsequently located at a beach. Results illustrate the benefit of using a complementary approach and consideration of the two way transfer of materials (Dawson and Hillier, 2010). References Fitzpatrick R.W. and Raven M.D. (2012) How Pedology and mineralogy helped solve a double murder case: Using forensics to inspire future generations of soil scientists. Soil Horizons. 53 (5) doi:10.2136/sh12-05-0016. Dawson, L.A. Hillier, S. (2010) Measurement of soil characteristics for forensic applications. Surface and Interface Analysis, 42, 363-377.

Dawson, Lorna; Fitzpatrick, Robert

2013-04-01

332

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

333

Characteristic high- and low-frequency dental traits in sub-Saharan African populations.  

PubMed

In an earlier investigation (Irish [1993] Biological Affinities of Late Pleistocene Through Modern African Aboriginal Populations: The Dental Evidence [Ann Arbor: University Microfilms]), biological affinities of 32 sub-Saharan and North African dental samples were estimated using comparative analyses of 36 dental morphological traits. Marked dental homogeneity was revealed among samples within each of the two geographic regions, but significant interregional differences were noted. Assuming dental phenetic expression approximates or is an estimate of genetic variation, the present study of 976 sub-Saharan-affiliated Africans indicates they are not closely related to other world groups; they are characterized by numerous morphologically complex crown and root traits. Turner ([1984] Acta Anthropogenetica 8:23-78; [1985] in R Kirk and E Szathmary (eds.): Out of Asia: Peopling the Americas and the Pacific [Canberra: The Journal of Pacific History], pp. 31-78; [1990] Am. J. Phys. Anthropol. 82:295-318; [1992] Persp. Hum. Biol. 2/Archaeol. Oceania 27:120-127; [1992] in T Akaszawa, K Aoki, and T Kimura (eds.): The Evolution and Dispersal of Modern Humans in Asia [Tokyo: Hokusen-Sha Publishing Co-], pp. 415-438) reports that Northeast Asian/New World sinodonts also have complex teeth relative to Europeans, Southeast Asian sundadonts, Australian/Tasmanians, and Melanesians. However, sinodonty is characterized by UI1 winging, UI1 shoveling, UI1 double shoveling, one-rooted UP1, UM1 enamel extension, M3 agenesis, and three-rooted LM1. Sub-Saharan peoples exhibit very low frequencies of these features. It is proposed that the collection of dental traits which best differentiate sub-Saharan Africans from other worldwide samples includes high frequencies of the Bushman Canine, two-rooted UP1, UM1 Carabelli's trait, three-rooted UM2, LM2 Y-groove pattern, LM1 cusp 7, LP1 Tome's root, two-rooted LM2, UM3 presence, and very low incidences of UI1 double shoveling and UM1 enamel extension. This suite of diagnostic traits is termed the sub-Saharan African dental complex. PMID:9140538

Irish, J D

1997-04-01

334

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

PubMed

In the UK, stabbing is the most common cause of homicide. The weapons used include knives, swords, screwdrivers and glass shards. Quantifying the exact force used in a stabbing incident is considered to be a difficult area due to the large number of variables present, such as sharpness of weapon, angle of attack and relative movements of the people involved. Having quantifiable data would allow a forensic pathologist to make a more informed decision when it comes to answering the commonly posed question in court "what was the degree of force involved in the stabbing incident?" The answer to this question is considered significant in determining an alleged assailant's intent to cause harm. This paper presents results of the first detailed study relating geometry of screwdrivers to the forces required for penetration. Additionally, a range of other blunt weapons such as pens and chisels have also been studied. A silicone rubber-foam analogue has been used as the main skin simulant owing to it having similar mechanical properties to that of human skin and giving highly repeatable results. Different screwdrivers of varying shape and size have been tested (i.e. slotted, Phillips, posidriv and Torx), along with other implements including chisels and pens. The weapon geometry was characterised and related to the peak force required for penetration. Our results show that there is a direct correlation between the cross-sectional area of a screwdriver head and the amount of force required for penetration. Screwdrivers with larger cross-sectional areas require a significantly greater force to penetrate (forces in the region of 100-120 N) but "sharper" slotted screwdrivers penetrate with much lower forces (~30 N). The forces required for penetrating the rubber-foam analogue with screwdrivers are higher than for "sharp" knives, but in some cases similar to the forces required for stabbing with "blunt" knives. For the other weapons such as chisels and biros, the force required for penetration was again high and there was found to be a good relationship between area of the implement making contact and penetration force. PMID:21465182

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

2012-01-01

335

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

336

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

PubMed Central

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

Yrjälä, Kim; Alakukku, Laura; Palojärvi, Ansa

2012-01-01

337

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

NASA Astrophysics Data System (ADS)

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

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

2010-05-01

338

A comparison of collisions of saltating grains with loose and consolidated silt surfaces  

NASA Astrophysics Data System (ADS)

A particle tracking velocimetry system was used to study the trajectories of saltating sand particles as they impacted either consolidated (solid) or unconsolidated (loose) silt surfaces in a wind tunnel. The tunnel friction velocity varied between 0.26 and 0.3 m s-1. The average coefficient of restitution, defined as the ratio of postcollision velocity to precollision velocity, was found to be $\\epsilon$ = 0.64 for the loose bed and $\\epsilon$ = 0.79 for the solid bed, respectively. The average ratio of energy loss to impact energy was found to be EL/E0 = 0.58 for the loose bed and EL/E0 = 0.37 for the solid bed, respectively. These indices demonstrate that the loose bed absorbs more momentum and energy from the impacting sand particle. The average ejection angle was lower at 18° for the loose bed than 23° for the solid bed. In the loose surface, crater formations were observed to form with each impact. Surface profile measurements suggest an average crater volume of >0.1 mm3. For both beds, the coefficient of restitution decreases with the particle impact speed. In the case of the solid bed, the dependence on impact speed is in good agreement with a model of two colliding spheres with identical material properties. With regard to the loose bed, a model of the impacting particle motion as it plows through and plastically deforms the bed material is tested. If the ratio of the horizontal to vertical forces on the particle as it plows through the bed is taken as a linear function of impact speed, the model is in good agreement with measured data. This suggests that compaction of the surface may occur along with the plowing and displacement of loose bed material.

Gordon, Mark; McKenna Neuman, Cheryl

2009-11-01

339

Longwall mining of thin seams  

SciTech Connect

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

Curth, E A

1981-01-01

340

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

341

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

342

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

343

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

344

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

NASA Astrophysics Data System (ADS)

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

Sengupta, S.; Roy, I.

2015-01-01

345

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

346

Blasting casting to raise productivity  

SciTech Connect

Normally, surface mines employ draglines or truck and shovel systems to remove overburden. Blasting merely fragments and displaces the overburden enough to allow for easy digging. But during the past two decades, the effect of inflation and increased labor costs have encouraged unconventional methods of overburden removal. All of us are aware of the tremendous inflationary effects on costs of equipment, fuel, labor, interest, insurance, environmental compliance, etc. This has allowed the authors to take a new look at the use of explosives as an effective alternate method of overburden removal. This technique is known by several names, but basically blast casting or just casting best describes it. Other terms in vogue are explosive casting, controlled trajectory blasting, trajectory control blasting, and whatever terminology comes to mind.

Pilshaw, S.R.

1987-07-01

347

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

348

The dental morphology of Pima Indians.  

PubMed

Fourteen morphologic crown traits were observed in a sample of 1528 Pima Indians of south-central Arizona. Pima dentitions are characterized by high frequencies of shoveling, incisor winging, the hypocone, the lower canine distal accessory ridge, cusp 6, and the protostylid. They exhibit low frequencies of the metaconule and lower premolar multiple lingual cusps and moderate frequencies of the canine tubercle, Carabelli's trait, cusp 7, and lower second molars with four cusps and X groove patterns. When Pima crown trait frequencies were compared to those of 13 Southwest Indian samples, their closest affinities were to other Uto-Aztecan groups, the Papago and Hopi. The Pima are most divergent from Athapaskans and are also clearly removed from Yuman speaking groups and the Zuni. In general, the pattern of dental morphologic variation in the Southwest corresponds closely to linguistic divisions. PMID:6869510

Scott, G R; Potter, R H; Noss, J F; Dahlberg, A A; Dahlberg, T

1983-05-01

349

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

350

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

PubMed

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

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

2003-09-01

351

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

352

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

USGS Publications Warehouse

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

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

2010-01-01

353

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

SciTech Connect

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

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

1981-11-01

354

Ground control failures. A pictorial view of case studies  

SciTech Connect

The book shows, in pictorial views, many forms and/or stages of types of failures in mines, for instance, cutter, roof falls, and cribs. In each case, the year of occurrence is stated in the beginning so that the environment or technological background under which it occurred are reflected. The narrative than begins with the mining and geological conditions, followed by a description of the ground control problems and recommended solutions and results, if any. The sections cover failure of pillars, roof falls, longwall, roof bolting, multiple-seam mining, floor heave, longwall, flooding and weathering of coal, old workings, and shortwall and thin-seam plow longwall.

Peng, S.S.

2007-07-01

355

Reflection and transmission of a monochromatic gravity wave at oblique incidence to a step  

E-print Network

combinations of the computer pro- gram input parameters, step configuration, incidence anglr and wave period, are considered. Each case is subjected to the same tr atment. plow regime properties are calculated such as the field velocity com- ponents... of propagat LUll slue I occur over a dis tance whic'n i s smai. I com- pared to a wavelength. Th- reflecting meciianism which is considered in t'nis pacer is the abrupt change in depth along a straight line with a monochromatic, plane, progressive gravity...

Wanstrath, John Joseph

2012-06-07

356

Plant responses and cattle gains from different intensities of spring grazing on crested wheatgrass at two sites in northern New Mexico  

E-print Network

for seven years, compared with average stocking for the U- and 6-inch stubble heights of 32.0 and 27.3 heifer-days per acre. Stocking on the 2-inch stubble treatment vailed from 19.5 to 63.0 heifer-days per acre. From 19U8 through 1956 heifers gained... of approxi? mately 1,200 acres was plowed and seeded to crested wheatgrass in 19k7 and 19U8. Pastures 1?2, b2, and 5 l acres in size were located and fenced within the 19^7 seeded area in 1950 and were grazed at different intensities, pasture 1...

Springfield, H. W.

2013-10-04

357

Availability of soil organic phosphorus and fertilizer phosphorus applied to coastal bermudagrass (cynodon dactylon l.) on Houston black clay  

E-print Network

. Kissel A two-year field study was conducted to determine the effect of moldboard plow1ng and nitrogen (N) and phosphorus (P) fertilization on P availability, Coastal bermudagrass yield, and m1neralization of soil organic matter. The field study... included 4 tillage-P fertil1zer comb1nations w1th six different annual N application rates. In addition, a three-month greenhouse study was conducted to determine the dry matter y'. elds and total P uptake in Coastal bermuda- grass with changes in soil...

Krautmann, Jolly Yang

1978-01-01

358

Using a Stream Table to Investigate Erosion Control  

NSDL National Science Digital Library

This activity will introduce students to water-induced topsoil erosion and different ways to control it. Using a stream table (prepared by the teacher), they will vary the surface of the 'soil', and the height of the table, pour in water, and observe sheet, rill, and gully erosion. They can also investigate the effects of check dams (by plugging gullies with pebbles), observe the results of contour plowing, and test the effectiveness of different types of mulch (straw, shredded paper, pine needles, etc.) in preventing erosion. Instructions for constructing a stream table, a student worksheet, and discussion questions are provided.

2005-10-06

359

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

360

Black soldier fly (Diptera: Stratiomyidae) colonization of pig carrion in south Georgia.  

PubMed

The black soldier fly, Hermetia illucens (L.), is thought to colonize corpses 20-30 days postmortem. However, recent observations indicate this might not be true for all cases. Therefore, we conducted a study examining colonization by the black soldier fly and other Diptera on pig carrion in a plowed field in southern Georgia from 20 September through 21 February. Our data indicate black soldier flies could colonize a corpse within the first week after death. Knowing this information could prevent a serious mistake in estimating the time at which a corpse is colonized by this species. This study also represents the first record of Chrysomya rufifacies in Georgia. PMID:15831010

Tomberlin, Jeffery K; Sheppard, D Craig; Joyce, John A

2005-01-01

361

Review of an internship with Ouray District United States Forest Service  

E-print Network

been created in the Ponderosa pine (Pinus ~dj ? kb h (n ppj . H y f h 1 p were built solely for livestock, however, these and the later ones have added greatly to the habitat of many migratozy and nonmigratory wildlife species. These ponds range... were not the only places seeded on the Ouray District. A mixture of native grass was broadcasted on a Ponderosa pine plantation. The 120 ha plantation on the iVeale Allotment had been zoot plowed for pine seedlings. It was seeded with grass...

Caddy, Mark W

2012-06-07

362

In the Footsteps of Charles Darwin: Patterns of Coastal Subsidence and Uplift Associated with Seamount Subduction, Basal Fore-arc Erosion and Seamount Accretion in Latin America  

NASA Astrophysics Data System (ADS)

In Geological Observations on South America (1846), Charles Darwin described beds of late Cenozoic marine seashells that were uplifted to elevations as much as several hundred meters above some localities on the western coastline of South America and implied that the whole coast was uplifting at geologic time scales. We know now that such evidence is generally restricted to coastal embayments above fore-arc basins where offshore seamounts are colliding with the South American fore arc (e.g., the Juan Fernandez seamount chain, Valpariso Basin and Valpariso Bay). We suggest that the phenomena of basal fore-arc erosion and basin formation and coastal uplift are closely related to effects of seamount subduction. Marine multibeam sonar images and multichannel seismic reflection surveys by others demonstrate that seamounts, although locally cut by normal faults in the outer-rise/near-trench region, initally subduct intact and the primary interaction with the toe of the fore arc is plowing, with material eroded from the fore arc that accumulates above and on the margins of the seamount. Submarine landslides above such regions over-steepened by plowing can lead to coastal embayments far upslope of the plowing. Such plowing interaction can therefore lead to the formation of large forearc basins and coastal embayments such as those at Valpariso, Chile, or narrow corridors of subsidence in the wake of subducting seamounts in Costa Rica. It is also known that the transition between interplate thrust seismicity, representing mechanical coupling between the plates, and aseismic slip occurs at depths of typically 30-60 km and often geographically near coastlines that mark the boundary between outer fore-arc subsidence and inner fore-arc uplift. We suggest that decoupling can occur at the base of seamounts (i.e., the originally sedimented seafloor on which the seamount lavas are laid down) and that such seamounts can be accreted to the fore arc above and lead to coastal uplift. Such basal decoupling is known to occur under active volcanic islands in the open ocean in connection with rifting and gravitational spreading, such as beneath the island of Hawaii. The spatial and temporal patterns of coastal uplift and subsidence on active margins can therefore record the local history of seamount subduction. This conceptual model explains the spatial patterns of offshore subsidence and coastal uplift in Chile and Costa Rica and also has implications for patterns of seismicity along the interplate thrust boundary.

Fisher, D. M.; Kirby, S. H.; David, S. W.

2004-12-01

363

Impact of conservation agriculture on harnessing sustainability and building resilience against land degradation in the northern Ethiopian highlands  

NASA Astrophysics Data System (ADS)

Conservation Agriculture (CA) aims at improving soil quality and crop yield whilst reducing runoff and topsoil erosion which raises the soil resilience to combat soil degradation. Different chemical, physical, and biological properties of a soil interact in complex ways that determine the crop productivity potential of the soil. Hence, a medium-term tillage experiment was carried out (2005 to 2011) on a Vertisol to evaluate changes in soil quality, runoff and soil loss due to CA-based field conservation practices in northern Ethiopia. The experimental layout was implemented in a randomized complete block design with three replications on permanent plots of 5 m by 19 m. The tillage treatments were derdero+ (DER+) with a furrow and permanent raised bed planting system, plowed once at planting by refreshing the furrow and with 30% standing crop residue retention, terwah+ (TER+) with plowing once at planting with 30% standing crop residue retention and contour furrows made at 1.5 m distance interval, and conventional tillage (CT) with a minimum of three tillage operations and removal of crop residues. All the plowing and reshaping of the furrows was done using the local ard plow mahresha. Local crop rotation practices followed during the seven years sequentially from the first to the seventh year included wheat-teff-wheat-barley-wheat-teff-grass pea. Glyphosate was sprayed starting from the third year (2007) at 2 l ha-1 before planting to control pre-emergent weed in DER+ and TER+. Significantly different (p<0.05) mean runoff coefficients (%) in 7-yrs of 13, 20 and 27 were recorded for DER+, TER+ and CT, respectively. Mean soil losses of 7-yrs were 4.4, 12.5 and 18 t ha-1 y-1 in DER+, TER+ and CT, respectively. Among the several assessed soil properties, SOM, N, P, soil microbial biomass carbon, aggregate stability index, consistency index, cone index, air capacity and macroporosity were shown to significantly increase in soils subjected to DER+ planting system compared to CT, specifically at 0-10 cm depth. Aggregate instability index, crack size at harvest, relative water capacity and plastic limit were significantly larger in CT compared to CA treatments. Adoption of improved local practices of DER+ and TER+ planting systems that employ conservation agriculture principles can reduce runoff, soil loss and improve crop yield and soil quality and thus, sustainability in Vertisols. Keywords: Soil resilience, Vertisol, conservation agriculture, field conservation practices, soil quality

Araya, Tesfay; Cornelis, Wim M.; Govaerts, Bram; Bauer, Hans; Deckers, Jozef; Nyssen, Jan

2013-04-01

364

Stubble Mulch Management for Water Conservation and Erosion Control on Hardlands of the Southern Great Plains.  

E-print Network

. Fields to be left in suitable condition for planting crops. After considerable testing of various combinations of sweeps and other implements, it was found that to do a successful job of subsurface tillage a subtiller should: 1. Be capable... ------- Moldboard plow.. 20.3 4.2 19.7 4.4 1.8 31.8 nnewayplow . 20.1 6.024.5 6-71 2.6128." Subtillage ....... 119.01 7.1126.41 6.91 6.0134.31 An average of 2.6 bushels more wheat per acre was obtained from the continuous wheat plots which were subtilled than...

Johnson, Wendell C. (Wendell Clifford); Van Doren, C. E.; Whitfield, Charles J. (Charles James)

1949-01-01

365

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

SciTech Connect

Plant cover established without purposeful soil preparation or seeding was measured on ground disturbed by plowing in Washington and by aboveground nuclear explosions in Nevada. After a time lapse of three decades in Washington and two decades in Nevada, fewer species were self-established on the disturbed ground than the nearby undisturbed ground. Alien annual plants were the dominants on the disturbed ground. Cheatgrass (Bromus tectorum) dominated abandoned fields in Washington, and filaree (Erodium cicutarium) dominated disturbed ground in Nevada. Perennial grasses and shrubs appeared to be more successful as invaders in Nevada than in Washington. This distinction is attributed to the superior competitive ability of cheatgrass in Washington.

Rickard, W.H.; Sauer, R.H.

1982-01-01

366

Oats in Texas.  

E-print Network

erosion. Seed Treatment Fig. 2. Oats frequently are sown in iielrls where cotton was the previous crop. with a disc or moldboard plow as soon after harvest as possible. The soil then should be disc-harrowed when necessary for the control of weeds... in oat- growing areas. Plants and seed of this weed are similar in appearance to cultivated oats. (See Figure 2.) True wild oat seed are hairy, shatter readily and have a long, black twisted awn. False wild oats and hybrids with culti- vated oats...

Spears, Ben; Coffey, Lee

1957-01-01

367

Hairy Vetch, Bur Clover and Oats as Soil-Building Crops for Cotton and Corn in Texas.  

E-print Network

-8-4 fertilizer on the Boswell soil at Tyler. Yield of Corn No cover crop was grown following the cotton and preceding the corn. The corn received the residual effects of the green manures and fertilizers and, in addition, 100 pounds per acre of sulfate... obtained at Tyler show that preparing the seedbed by plowing destroys the surface cover, as corn and cotton stalks, and leaves the soil in a highly ive condition. On the other hand, disking corn land leaves ~gh crop residues on or near the surface...

Morris, H. F. (Harry Forest); Johnson, P. R. (Paul Rufus); Reynolds, E. B. (Elbert Brunner)

1950-01-01

368

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

369

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

370

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

371

Endoscopic transcanal removal of symptomatic external auditory canal exostoses.  

PubMed

Exostoses are bony outgrowths of the external auditory canal (EAC) that can lead to cerumen entrapment, recurrent infections, and conductive hearing loss. When surgical removal is indicated, a drill or osteotome may be used via a post-auricular, endaural, or transcanal approach. Studies suggest that exostoses removed by transcanal osteotome result in decreased morbidity when compared to open, drilled approaches; however, inadvertent injury to the facial nerve or inner ear is a theoretical concern given the restrictive geometry of the EAC and challenges of visualizing the tip of the chisel through the microscope. The endoscope provides superior visualization of the external auditory canal and tympanic membrane compared to the microscope. We sought to demonstrate the efficacy and safety of endoscopic exostosis surgery with an osteotome. We find that the endoscope provides improved wide angled views without blind spots. There were no intraoperative complications. Endoscopic canaloplasty for exostoses may be readily applied. PMID:25459316

Kozin, Elliott D; Remenschneider, Aaron K; Shah, Parth V; Reardon, Edward; Lee, Daniel J

2014-10-16

372

X-Ray Fluorescence and Laser-Induced Breakdown Spectroscopy analysis of Roman silver denarii  

NASA Astrophysics Data System (ADS)

In this paper we present the results of a study performed on a large collection of silver Roman republican denarii, encompassing about two centuries of history. The joint use of Laser-Induced Breakdown Spectroscopy (LIBS) and X-Ray Fluorescence (XRF) spectroscopy allowed for an accurate determination of the coins' elemental composition; the measurements, performed mostly in situ at the 'Monetiere' in Florence, revealed a striking connection between the 'quality' of the silver alloy and some crucial contemporary events. This finding was used to classify a group of denarii whose dating was otherwise impossible. The comparison with other contemporary denarii disproves a recent theory on the origin of the so called 'serrated' denarii (denarii showing notched chisel marks on the edge of the coin).

Pardini, L.; El Hassan, A.; Ferretti, M.; Foresta, A.; Legnaioli, S.; Lorenzetti, G.; Nebbia, E.; Catalli, F.; Harith, M. A.; Diaz Pace, D.; Anabitarte Garcia, F.; Scuotto, M.; Palleschi, V.

2012-08-01

373

Were Viking Dry-dock methods in the Americas used earlier to Build Pyramids, with Outflow Eroding the Sphinx, and were Stonehenge, the Obelisks, and Moas Similarly Erected?  

NASA Astrophysics Data System (ADS)

Chisel-quarried recycled granite in MA is datable by runes to 1069 CE; it could corroborate dating by a LIDAR. Associated sites, possibly used by Vikings to dry-dock their ships, could have exploited lock-like controls, possibly a continued technology. Site-leveling at the Giza Pyramids proves water was used. `Locks' and body-immersion worked for building, moving, erecting, or watering, at sites like Stonehenge, The Hanging Gardens at Babylon, the Moas of Easter Island, or The Pyramids, where the eroding water discharge was deliberately flushed over the Sphinx complex. It enhance the electromagnetically excited blue light signals we can detect, especially at sites frequented by Molocket of ME. Information, as at America's Stonehenge, in NH, and constructions at Acton MA, at Giza or at Rumford ME proves that the Pyramids and Sphinx were engineered and built about 4500 BP.

McLeod, Edward; McLeod, Roger

2006-03-01

374

So I Sat Down with My Mother: Connectedness Orientation and Pupils' Independence  

NASA Astrophysics Data System (ADS)

Swedish educational policy underlines the importance of independence. In this paper we use socio-cultural theory and Foucault to explain how pupils’ independency is transformed into something else in their work. Our results derive from analyses of filmed sessions and entries in the pupils’ logbooks. Our findings demonstrate that the pupils’ definitions of independence differ from those of the course plan in several aspects: i) the use of certain resources is not considered to show lack of independence, ii) doing things yourself is considered being most independent and iii) to follow instructions, even if this means violating your unique personal thought, is considered a prerequisite for passing/getting good grades and as such a necessary adaption to the school context, sooner than a sign of dependency. Consequently we argue that pupil independency should be regarded as a phenomenon chiseled out within a community of practice rather than a personal capacity.

Eklöf, Anders; Nilsson, Lars-Erik; Svensson, Peter

375

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

376

Visual inspections of N Reactor horizontal control rod channels  

SciTech Connect

This document describes the examination of thirteen horizontal control rod channels during the N Reactor Surveillance Program campaigns of 1987 and 1988. Traverses with miniature video cameras recorded the condition and relative positions of graphite blocks that form channel walls. The major conclusion confirms that no conditions exist that would prevent rod insertion. Where encroachment of broken filler block keys into the channel indicated a potential for rod motion impairment their removal by displacement into gaps between blocks was performed as preventive maintenance. In some locations a chisel was used in clearing keys lodged in gaps between tube blocks. Other observations include counts of safety balls observed in channels, breaks in tube blocks and Tee-bars and separations at Tee-bar junctions that results from axial graphite contraction. 15 refs., 18 figs., 6 tabs.

Woodruff, E.M.

1990-07-01

377

Investigation of homicides interred in concrete--the Los Angeles experience.  

PubMed

Decedents interred in concrete present unique problems and investigation of these deaths necessitates a team of forensic specialists. The Los Angeles County Department of Coroner has had five such deaths in the past 18 years. The buried cases needed layer-by-layer excavation to establish the time and cause of death. Metal detectors are often used in this process. X-rays of the interred remains were completed to help with locating the decedent's position in the concrete. The breaking of concrete in some of the cases required the use of a sledgehammer and later a chisel in a manner that would not damage the remains. Postmortem dismemberment was frequent in our cases. The decedents were all female or prepubescent children, and the perpetrators were closely related to the decedents. While concrete can interfere with determination of postmortem interval, it can also preserve the remains and assist with identification. PMID:18279257

Toms, Carla; Rogers, Christopher B; Sathyavagiswaran, Lakshmanan

2008-01-01

378

[Oncogenic hypophosphatemic osteomalacia].  

PubMed

In the courses of six years a severe hypophosphataemic osteomalacia, painful motor impairment and multiple rib fractures developed in a 51-year-old man. The symptoms gradually improved within one year under treatment with 3 micrograms daily of 1,25-dihydroxycholecalciferol, 3 g phosphorus and 3 g calcium, and biochemical parameters and the bone scintigram became normal. Ultimately, computed tomography, scintigraphy and digital subtraction angiography revealed a highly vascularized tumour in the condylar aspect of the right femur, and it was chiselled out. Histologically it was a mesenchymal phosphaturic tumour of haemangiopericytoma type of questionable benignity. After the operation the patient was symptom-free for some weeks without any drug treatment, but the latter was then resumed because of renewed bone pain. By now, two years later, he is essentially without pain and has full mobility. However, repeat scintigraphy and angiography revealed renewed tumour growth in the right femoral condyle. PMID:2737097

Schultze, G; Delling, G; Faensen, M; Haubold, R; Loy, V; Molzahn, M; Pommer, W; Semler, J; Trempenau, B

1989-07-01

379

Benchmarks for target tracking  

NASA Astrophysics Data System (ADS)

The term benchmark originates from the chiseled horizontal marks that surveyors made, into which an angle-iron could be placed to bracket ("bench") a leveling rod, thus ensuring that the leveling rod can be repositioned in exactly the same place in the future. A benchmark in computer terms is the result of running a computer program, or a set of programs, in order to assess the relative performance of an object by running a number of standard tests and trials against it. This paper will discuss the history of simulation benchmarks that are being used by multiple branches of the military and agencies of the US government. These benchmarks range from missile defense applications to chemical biological situations. Typically, a benchmark is used with Monte Carlo runs in order to tease out how algorithms deal with variability and the range of possible inputs. We will also describe problems that can be solved by a benchmark.

Dunham, Darin T.; West, Philip D.

2011-09-01

380

A balsa violin  

NASA Astrophysics Data System (ADS)

Almost half a century ago John Schelleng determined the scaling rules that show how violins can be made from nontraditional materials. These principles suggest that balsa wood may be a possible, if unlikely, construction material. To test this idea, a balsa violin was constructed and found to be playable. Its vibrational behavior is shown to be in agreement with Schelleng's scaling rules. The instrument was not difficult to build, and its construction can be repeated by anyone of moderate skill with a chisel and sandpaper and access to an audio frequency analysis program. The reward is a tactile appreciation for the vibrational behavior of materials and the physics of musical instruments that is difficult to gain otherwise.

Waltham, Chris

2009-01-01

381

[Otosclerosis like bone in osteogenesis imperfecta tarda].  

PubMed

Bone like in otosclerosis from a 34-years-old man, from 33 years and 22 years old women, suffering from osteogenesis imperfecta tarda, with hardness of hearing in both ears were removed with chisel from the lower border of the oval window. After that a stapedectomy was accomplished. The stapedial crura have been genetically interrupted or broken, the footplate attached to the oval window. The bone from the border of the oval window was prepared for the histological examination. The specimens were coloured with Hematoxylin-Eosin and corresponding to Gomöri. In the bone similar cartilage osteoclasia and osteogenesis are rare. There are in the chondroosseous bone rooms filled with connective tissue. The diseased osseous labyrinth in osteo genesis imperfecta tarda must be regarded as a special morphogenetic formation of osteopsathyrosis. PMID:128672

Müller, E; Majer, R

1975-12-01

382

Control of Tylenchulus semipenetrans on Citrus With Aldicarb, Oxamyl, and DBCP.  

PubMed

Soil application of DBCP (l,2-dibromo-3-chloropropane) and foliar applications of oxamyl (methyl N',N'-dimethyl-N-[(methylcarbamoyl)oxy]-l-thiooxamimidate) were compared for control of Tylenchulus semipenetrans in a grapefruit (Citrus paradisi) orchard, DBCP reduced nematode populations and increased fruit growth rate, fruit size at harvest, and yield compared to the untreated controls in the 2 years following treatments. Foliar applications of oxamyl reduced nematode populations and increased fruit growth rate slightly the first year, but not in the second. Foliar applications of oxamyl did not improve control attained by DBCP alone. Soil application of aldicarb [2-methyl-2-(methylthio)propionaldehyde-O-(methylcarbamoyl)oxime] or DBCP to an orange (C. sinensis) orchard reduced T. semipenetrans populations in the 3 years tested and increased yield in 1 of 3 years. Aldicarb treatment reduced fruit damage caused by the citrus rust mite, Phyllocoptruta oleivora. Aldicarb, applied at 5.7 or 11.4 kg/ha, by disk incorporation or chisel injection, was equally effective in controlling nematodes, improving yields, fruit size, and external quality. In a grapefruit orchard, chisel-applied aldicarb reduced nematode populations and rust mite damage and increased yields in both years and increased fruit size in one year. The 11.4-kg/ha rate was slightly more effective than the 5.7-kg/ha rate. Aldicarb appears to be an adequate substitute for DBCP for nematode control in Texas citrus orchards and well-suited to an overall pest management system for Texas citrus. PMID:19300660

Timmer, L W; French, J V

1979-10-01

383

Fatty acid composition of adipose tissue triglycerides after weight loss and weight maintenance: the DIOGENES study.  

PubMed

Fatty acid composition of adipose tissue changes with weight loss. Palmitoleic acid as a possible marker of endogenous lipogenesis or its functions as a lipokine are under debate. Objective was to assess the predictive role of adipose triglycerides fatty acids in weight maintenance in participants of the DIOGENES dietary intervention study. After an 8-week low calorie diet (LCD) subjects with > 8 % weight loss were randomized to 5 ad libitum weight maintenance diets for 6 months: low protein (P)/low glycemic index (GI) (LP/LGI), low P/high GI (LP/HGI), high P/low GI (HP/LGI), high P/high GI (HP/HGI), and a control diet. Fatty acid composition in adipose tissue triglycerides was determined by gas chromatography in 195 subjects before the LCD (baseline), after LCD and weight maintenance. Weight change after the maintenance phase was positively correlated with baseline adipose palmitoleic (16:1n-7), myristoleic (14:1n-5) and trans-palmitoleic acid (16:1n-7t). Negative correlation was found with baseline oleic acid (18:1n-9). Lower baseline monounsaturated fatty acids (14:1n-5, 16:1n-7 and trans 16:1n-7) in adipose tissue triglycerides predict better weight maintenance. Lower oleic acid predicts lower weight decrease. These findings suggest a specific role of monounsaturated fatty acids in weight management and as weight change predictors. PMID:23098653

Kunešová, M; Hlavatý, P; Tvrzická, E; Sta?ková, B; Kalousková, P; Viguerie, N; Larsen, T M; van Baak, M A; Jebb, S A; Martinez, J A; Pfeiffer, A F H; Kafatos, A; Handjieva-Darlenska, T; Hill, M; Langin, D; Zák, A; Astrup, A; Saris, W H M

2012-01-01

384

BotEC: The Magnitude of the India-Asia Collision  

NSDL National Science Digital Library

Question: The story of the Himalayas can be traced back to the breakup of the supercontinent, called Pangaea, about 200 million years ago, when India began its rapid movement northward towards Asia. Asia was a much smaller continent then. Then, between 45 and 55 million years ago, India and Asia collided. Before collision, India moved northward at about 7-10 centimeters per year. Remarkably, India's northward movement was slowed only a little after the collisionâit continues to plow into Asia at a rate of 5-6 centimeters per year. We can measure the present northward movement of India into Asia using GPS measurements over a period of time. So, there is little doubt of the continued movement of India. There is much debate about how the northward march of India into Asia is being accommodated. Of course, the high Himalayan Plateau is a manifestation of this collision between two continents. Now refer to a map of the USA. For the sake of comparison, if India were to have collided with North America near Washington, D.C. and continued to plow westward into North America at 6 centimeters per year for 55 million years, then where would the "front" of the collision zone be presently? Name a major city in the USA that is at the correct approximate distance from Washington, D.C.

Kresan, Peter

385

[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

386

Specific features of bacterial communities in floodplain agrocenoses  

NASA Astrophysics Data System (ADS)

The analysis of the taxonomic structure of the bacterial complexes in the alluvial soils of the Oka River valley allowed revealing the distinct differences in the spectrum of the bacterial dominants in the virgin and cultivated soils. Arthrobacter and pigment coryneform bacteria are shown to predominate in the virgin soil; bacilli and pseudomonades are common in the soil under vegetables. On cabbage leaves and carrot roots (both healthy and rotten), the spectrum of dominants is composed of two genera of enterobacteria: Pantoea and Erwinia. As a result of the plowing in of vegetables into the soil, enterobacteria accumulate; among them, phytopathogenic species are present. Within a year after this plowing in and the new yield, the enterobacteria practically disappeared, but myxobacteria and cytophages developed. Since these bacteria belong to the cellulose-destroying prokaryotes, the increase in their contents in the soil testified to their participation in the decomposition of the buried vegetable residues. Weeds are known to concentrate various bacterial forms in the phylloplane; they enter from different ecological niches: soil, water, meadow, and agricultural plants. Representatives of phytopathogenic bacteria as minor components were found on weeds.

Dobrovol'Skaya, T. G.; Leont'evskaya, E. A.; Sneg, A. A.; Balabko, P. N.

2010-04-01

387

[Litter decomposition and nutrient release in Acacia mangium plantations established on degraded soils of Colombia].  

PubMed

Several factors control the decomposition in terrestrial ecosystems such as humidity, temperature, quality of litter and microbial activity. We investigated the effects of rainfall and soil plowing prior to the establishment of Acacia mangium plantations, using the litterbag technique, during a six month period, in forests plantations in Bajo Cauca region, Colombia. The annual decomposition constants (k) of simple exponential model, oscillated between 1.24 and 1.80, meanwhile k1 y k2 decomposition constants of double exponential model were 0.88-1.81 and 0.58-7.01. At the end of the study, the mean residual dry matter (RDM) was 47% of the initial value for the three sites. We found a slow N, Ca and Mg release pattern from the A. mangium leaf litter, meanwhile, phosphorus (P) showed a dominant immobilization phase, suggesting its low availability in soils. Chemical leaf litter quality parameters (e.g. N and P concentrations, C/N, N/P ratios and phenols content) showed an important influence on decomposition rates. The results of this study indicated that rainfall plays an important role on the decomposition process, but not soil plowing. PMID:21516640

Castellanos-Barliza, Jeiner; León Peláez, Juan Diego

2011-03-01

388

Evaluation of the possibility to use the plant-microbe interaction to stimulate radioactive (137)Cs accumulation by plants in a contaminated farm field in Fukushima, Japan.  

PubMed

Field experiments in a contaminated farmland in Nihonmatsu city, Fukushima were conducted to assess the effectiveness of the plant-microbe interaction on removal of radiocesium. Before plowing, 93.3 % of radiocesium was found in the top 5 cm layer (5,718 Bq kg DW(-1)). After plowing, Cs radioactivity in the 0-15 cm layer ranged from 2,037 to 3,277 Bq kg DW(-1). Based on sequential extraction, the percentage of available radiocesium (water soluble + exchangeable) was fewer than 10 % of the total radioactive Cs. The transfer of (137)Cs was investigated in three agricultural crops; komatsuna (four cultivars), Indian mustard and buckwheat, inoculated with a Bacillus or an Azospirillum strains. Except for komatsuna Nikko and Indian mustard, inoculation with both strains resulted in an increase of biomass production by the tested plants. The highest (137)Cs radioactivity concentration in above-ground parts was found in Bacillus-inoculated komatsuna Nikko (121 Bq kg DW(-1)), accompanied with the highest (137)Cs TF (0.092). Furthermore, komatsuna Nikko-Bacillus and Indian mustard-Azospirillum associations gave the highest (137)Cs removal, 131.5 and 113.8 Bq m(-2), respectively. Despite the beneficial effect of inoculation, concentrations of (137)Cs and its transfer to the tested plants were not very high; consequently, removal of (137)Cs from soil would be very slow. PMID:25398196

Djedidi, Salem; Terasaki, Akimi; Aung, Han Phyo; Kojima, Katsuhiro; Yamaya, Hiroko; Ohkama-Ohtsu, Naoko; Bellingrath-Kimura, Sonoko Dorothea; Meunchang, Phatchayaphon; Yokoyama, Tadashi

2014-11-15

389

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

390

Heintzmann continuous longwall miner  

SciTech Connect

Geologic Considerations for the Continuous Longwall Miner The mining of the thin seams allows: (1) an optimum return of the capital invested, (2) delay mining of seams at greater depth, or opening other mines, (3) a maximization of resources, (4) a prolongation of mine-lifespan. Meanwhile, deposits having seam thicknesses of about 3 feet have been proven to yield economical gains. This situation requires mining machines that possess the ability to effectively mine thin seams containing tough but plowable coal. To reach this goal, the plow systems were equipped to achieve more horsepower. The use of plows has declined due to: (1) higher weight, (2) higher purchase costs, (3) and higher repair costs. In the cutting conveying method, two objectives have to be addressed: (1) The load on the cutting machines has to be reduced by a more effective cutting-principle and a working method adjusted to the coal. (2) Cutting and conveying have to be simultaneous. Only with the CLM Miner, can mining rates be advanced in thin seams.

Guse, K. [Heintzmann, Cedar Bluff, VA (United States); Polsh, J.

1996-12-31

391

Fatty Acid Composition of Adipose Tissue Triglycerides After Weight Loss and Weight Maintenance: the DIOGENES Study  

PubMed Central

Summary Fatty acid composition of adipose tissue changes with weight loss. Palmitoleic acid as a possible marker of endogenous lipogenesis or its functions as a lipokine are under debate. Objective was to assess the predictive role of adipose triglycerides fatty acids in weight maintenance in participants of the DIOGENES dietary intervention study. After an 8-week low calorie diet (LCD) subjects with > 8 % weight loss were randomized to 5 ad libitum weight maintenance diets for 6 months: low protein (P)/low glycemic index (GI) (LP/LGI), low P/high GI (LP/HGI), high P/low GI (HP/LGI), high P/high GI (HP/HGI), and a control diet. Fatty acid composition in adipose tissue triglycerides was determined by gas chromatography in 195 subjects before the LCD (baseline), after LCD and weight maintenance. Weight change after the maintenance phase was positively correlated with baseline adipose palmitoleic (16:1n-7), myristoleic (14:1n-5) and trans-palmitoleic acid (16:1n-7t). Negative correlation was found with baseline oleic acid (18:1n-9). Lower baseline monounsaturated fatty acids (14:1n-5, 16:1n-7 and trans 16:1n-7) in adipose tissue triglycerides predict better weight maintenance. Lower oleic acid predicts lower weight decrease. These findings suggest a specific role of monounsaturated fatty acids in weight management and as weight change predictors. PMID:23098653

KUNEŠOVÁ, M.; HLAVATÝ, P.; TVRZICKÁ, E.; STA?KOVÁ, B.; KALOUSKOVÁ, P.; VIGUERIE, N.; LARSEN, T. M.; VAN BAAK, M. A.; JEBB, S. A.; MARTINEZ, J. A.; PFEIFFER, A. F. H.; KAFATOS, A.; HANDJIEVA-DARLENSKA, T.; HILL, M.; LANGIN, D.; ŽÁK, A.; ASTRUP, A.; SARIS, W. H. M.

2013-01-01

392

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

393

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

394

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

395

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

396

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

397

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

398

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

399

A rapid, controlled-environment seedling root screen for wheat correlates well with rooting depths at vegetative, but not reproductive, stages at two field sites  

PubMed Central

Background and Aims Root length and depth determine capture of water and nutrients by plants, and are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to determine speed, repeatability and relatedness to performance of young and adult plants in the field. Methods Recombinant inbred lines (RILs) and diverse genotypes were grown in rolled, moist germination paper in growth cabinets, and primary root number and length were measured when leaf 1 or 2 were fully expanded. For comparison, plants were grown in the field and root systems were harvested at the two-leaf stage with either a shovel or a soil core. From about the four-leaf stage, roots were extracted with a steel coring tube only, placed directly over the plant and pushed to the required depth with a hydraulic ram attached to a tractor. Key Results In growth cabinets, repeatability was greatest (r = 0·8, P < 0·01) when the paper was maintained moist and seed weight, pathogens and germination times were controlled. Scanned total root length (slow) was strongly correlated (r = 0·7, P < 0·01) with length of the two longest seminal axile roots measured with a ruler (fast), such that 100–200 genotypes were measured per day. Correlation to field-grown roots at two sites at two leaves was positive and significant within the RILs and cultivars (r = 0·6, P = 0·01), and at one of the two sites at the five-leaf stage within the RILs (r = 0·8, P = 0·05). Measurements made in the field with a shovel or extracted soil cores were fast (5 min per core) and had significant positive correlations to scanner measurements after root washing and cleaning (>2 h per core). Field measurements at two- and five-leaf stages did not correlate with root depth at flowering. Conclusions The seedling screen was fast, repeatable and reliable for selecting lines with greater total root length in the young vegetative phase in the field. Lack of significant correlation with reproductive stage root system depth at the field sites used in this study reflected factors not captured in the screen such as time, soil properties, climate variation and plant phenology. PMID:23821620

Watt, M.; Moosavi, S.; Cunningham, S. C.; Kirkegaard, J. A.; Rebetzke, G. J.; Richards, R. A.

2013-01-01

400

Contact laser sphincterotomy: further experience and longer follow-up.  

PubMed

I report here the use of a crystal chisel contact tip firing Nd:YAG laser for transurethral sphincterotomy in 76 consecutive spinal cord injury patients. Their mean age was 53 years (range 26 to 77 years). Fifty-four (72%) were complete motor (Frankel A and B) and 21(28%) were incomplete lesions (Frankel C and D) They were evaluated with multichannel urodynamic equipment and 89% of the patients showed detrusor sphincter dyssynergia and 11% showed detrusor areflexia. Forty-three patients (56%) had previous electrocautery sphincterotomy and were not voiding well. A cystoscopic examination showed that 32% had an associated enlarged prostate and/or bladder-neck stenosis and 32% had associated wide-body strictures in the bulbous urethra. The crystal chisel contact tip firing Nd:YAG laser almost mimicked a hot diathermy knife to create an intraurethral incision as well as vaporizing the tissues. For sphincterotomy, a 12 o'clock incision was used from the verumontanum to the bulbous urethra. In patients with an associated enlarged prostate or bulging lateral lobes, 3 and 9 o'clock incisions were also made from the bladder-neck to the verumontanum and also vaporized the bulging prostate tissue. We used 25 to 40 watts for cutting, and vaporization of tissue and 15-25 watts to stop bleeding. The blood loss was less than 50 ml at surgery in 97.4% patients. None of the patients were transfused. An indwelling Foley catheter was usually left in situ for about 24 h and the majority of the patients were discharged the next day. All patients have been followed up at least every 6 months for a mean period of 27 months (range 16 to 41 months). The durability of surgery has been checked with linear array transrectal sonography and by urodynamic evaluation. Sixty-nine patients (92%) had adequate voiding, minimal to absent autonomic dysreflexia and no significant symptomatic urinary tract infection. There were seven patients who required repeat laser surgery within 2 to 5 months. All subsequent patients are voiding well with wide open bladder-neck and posterior urethra as shown on a voiding cystourethrogram. PMID:8963967

Perkash, I

1996-04-01

401

Carbon supply and storage in tilled and nontilled soils as influenced by cover crops and nitrogen fertilization.  

PubMed

Soil carbon (C) sequestration in tilled and nontilled areas can be influenced by crop management practices due to differences in plant C inputs and their rate of mineralization. We examined the influence of four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secale cereale L.)], biculture of legume and nonlegume (vetch and rye), and no cover crops (or winter weeds)} and three nitrogen (N) fertilization rates (0, 60 to 65, and 120 to 130 kg N ha(-1)) on C inputs from cover crops, cotton (Gossypium hirsutum L.), and sorghum [Sorghum bicolor (L.) Moench)], and soil organic carbon (SOC) at the 0- to 120-cm depth in tilled and nontilled areas. A field experiment was conducted on Dothan sandy loam (fine-loamy, siliceous, thermic Plinthic Paleudults) from 1999 to 2002 in central Georgia. Total C inputs to the soil from cover crops, cotton, and sorghum from 2000 to 2002 ranged from 6.8 to 22.8 Mg ha(-1). The SOC at 0 to 10 cm fluctuated with C input from October 1999 to November 2002 and was greater from cover crops than from weeds in no-tilled plots. In contrast, SOC values at 10 to 30 cm in no-tilled and at 0 to 60 cm in chisel-tilled plots were greater for biculture than for weeds. As a result, C at 0 to 30 cm was sequestered at rates of 267, 33, -133, and -967 kg C ha(-1) yr(-1) for biculture, rye, vetch, and weeds, respectively, in the no-tilled plot. In strip-tilled and chisel-tilled plots, SOC at 0 to 30 cm decreased at rates of 233 to 1233 kg C ha(-1) yr(-1). The SOC at 0 to 30 cm increased more in cover crops with 120 to 130 kg N ha(-1) yr(-1) than in weeds with 0 kg N ha(-1) yr(-1), regardless of tillage. In the subtropical humid region of the southeastern United States, cover crops and N fertilization can increase the amount of C input and storage in tilled and nontilled soils, and hairy vetch and rye biculture was more effective in sequestering C than monocultures or no cover crop. PMID:16825471

Sainju, Upendra M; Singh, Bharat P; Whitehead, Wayne F; Wang, Shirley

2006-01-01

402

Rotary Percussive Auto-Gopher for Deep Drilling and Sampling  

NASA Technical Reports Server (NTRS)

The term "rotary percussive auto-gopher" denotes a proposed addition to a family of apparatuses, based on ultrasonic/ sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive autogopher, the emphasis would be on developing an apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses. To recapitulate from the prior articles about USDCs: A USDC can be characterized as a lightweight, low-power jackhammer in which a piezoelectrically driven actuator generates ultrasonic vibrations and is coupled to a tool bit through a free mass. The bouncing of the free mass between the actuator horn and the drill bit converts the actuator ultrasonic vibrations into sonic hammering of the drill bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary rotary drilling, ordinary hammering, or ordinary steady pushing. The predecessor of the rotary percussive auto-gopher is an apparatus, now denoted an ultrasonic/sonic gopher and previously denoted an ultrasonic gopher, described in "Ultrasonic/ Sonic Mechanism for Drilling and Coring" (NPO-30291), NASA Tech Briefs Vol. 27, No. 9 (September 2003), page 65. The ultrasonic/sonic gopher is intended for use mainly in acquiring cores. The name of the apparatus reflects the fact that, like a gopher, it periodically stops advancing at the end of the hole to bring excavated material (in this case, a core sample) to the surface, then re-enters the hole to resume the advance of the end of the hole. By use of a cable suspended from a reel on the surface, the gopher is lifted from the hole to remove a core sample, then lowered into the hole to resume the advance and acquire the next core sample.

Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

2009-01-01

403

Prevention of vertebral body–splitting fractures after multilevel ProDisc-L implantation  

PubMed Central

Background Prior studies of multilevel ProDisc-L (PD-L) implants (Synthes Spine, Inc., West Chester, Pennsylvania) using the standard US technique have used conventional radiography postoperatively. We found vertebral body–splitting fractures (VB-SFs) in interposed vertebral bodies after 5 sequential multilevel PD-L device implantations using the standard US technique. These were identified with postoperative computed tomography (CT) but were not visible on plain radiographs. In an additional patient, we found that a stress-relieving, pilot holes–only technique did not prevent VB-SFs. The 5 patients operated on with the standard technique composed the background series against which we compared the incidence of VB-SFs in patients operated on with a modification of the standard US technique—a combination of stress-relieving pilot holes, removal of cortex in the chisel path, and a fenestrated chisel (PH/CR/FC)—intended to reduce the incidence of VB-SFs in multilevel PD-L constructs. Methods Patients receiving multilevel PD-L implants at 2 sites—1 in the United States and the other in Germany—were operated on with the PH/CR/FC technique and their postoperative CT scans evaluated for the presence of VB-SFs. The frequency of VB-SFs in these patients was compared with that of the 5 patients from the background series who were operated on by the standard US technique. The groups’ mean sex, age, body mass index, and vertebral body height, as well as average spinal T score, were also compared. Results No fractures were found in 13 interposed vertebral bodies in 11 patients operated on with the PH/CR/FC technique, as compared with 4 VB-SFs and 1 anterior keel cut–to–anterior keel cut fracture in 5 interposed vertebral bodies in 5 patients operated on with the US technique (P ? .001). Although the sample sizes were small, this difference in fracture rate was not associated with sex, age, body mass index, or average spinal T score. At up to 13 months of follow-up of patients in the background series, we found that VB-SFs tend not to bridge with bone, instead forming sclerotic margins. Conclusions The PH/CR/FC technique studied reduced the incidence of VB-SF in multilevel PD-L implants. Because previously published multilevel studies did not use postoperative CT scans and because VB-SFs are not visible on conventional radiography, the incidence of VB-SFs in multilevel PD-L applications may be higher than previously reported. Our findings may contribute to prevention of complications in total disc replacement.

Sullivan, Humbert G.; Bertagnoli, Rudolf; Nigogosyan, Mark A.; Ladwig, Nicholas R.; Born, Hayley L.; Cerniglia, Molly M.; Habbicht, Hartmann; Mathiason, Michelle A.; McHugh, Vicki L.

2012-01-01

404

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

405

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

406

Root-knot Nematode Management and Yield of Soybean as Affected by Winter Cover Crops, Tillage Systems, and Nematicides  

PubMed Central

Management of Meloidogyne incognita on soybean as affected by winter small grain crops or fallow, two tillage systems, and nematicides was studied. Numbers of M. incognita did not differ in plots planted to wheat and rye. Yields of soybean planted after these crops also did not differ. Numbers of M. incognita were greater in fallow than in rye plots, but soybean yield was not affected by the two treatments. Soybean yields were greater in subsoil-plant than in moldboard plowed plots. Ethylene dibromide reduced nematode population densities more consistently than aldicarb and phenamiphos. Also, ethylene dibromide increased yields the most and phenamiphos the least. There was a positive correlation (P = 0.001) of seed size (weight of 100 seeds) with yield (r = 0.79), indicating that factors affecting yield also affected seed size. PMID:19290104

Minton, N. A.; Parker, M. B.

1987-01-01

407

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

408

Soil fumigation: principles and application technology.  

PubMed

The principal soil fumigants and their order of discovery are carbon disulfide, chloropicrin, methyl bromide, 1,3-dichloropropene, ethylene dibromide, 1,2-dibromo-3-chloropropane, and methyl isothiocyanate. Biological activity of soil fumigants ranges from limited to broad spectrum. Fumigants diffuse through the continuous soil air space as gases. Physical and chemical characteristics determine diffusion rates, distribution between the soil air and moisture, and sorption onto and into the soil particles. The principal soil factors affecting the efficacy of each treatment are the size and continuity of air space, moisture, temperature, organic matter, and depth of placement. Application can be made overall with tractor injection or plow-sole, or as a row or bed treatment. Treatment for trees is best made in conjunction with tree site backhoeing. PMID:19287772

Lembright, H W

1990-10-01

409

Application of ecological, geological and oceanographic ERTS-1 imagery to Delaware's coastal resources management  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Data from twelve successful ERTS-1 passes over Delaware Bay have been analyzed with special emphasis on coastal vegetation, land use, current circulation, water turbidity and pollution dispersion. Secchi depth, suspended sediment concentration and transmissivity as measured from helicopters and boats were correlated with ERTS-1 image radiance. Multispectral signatures of acid disposal plumes, sediment plumes and slick were investigated. Ten vegetative cover and water discrimination classes were selected for mapping: (1) forest-land; (2) Phragmites communis; (3) Spartina patens and Distichlis spicata; (4) Spartina alterniflora; (5) cropland; (6) plowed cropland; (7) sand and bare sandy soil; (8) bare mud; (9) deep water; and (10) sediment-laden and shallow water. Canonical analysis predicted good classification accuracies for most categories. The actual classification accuracies were very close to the predicted values with 8 of 10 categories classified with greater than 90% accuracy indicating that representative training sets had been selected.

Klemas, V. (principal investigator); Bartlett, D. S.; Philpot, W. D.; Davis, G. R.; Rogers, R. H.; Reed, L.

1974-01-01

410

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

411

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

412

Soil Fumigation: Principles and Application Technology  

PubMed Central

The principal soil fumigants and their order of discovery are carbon disulfide, chloropicrin, methyl bromide, 1,3-dichloropropene, ethylene dibromide, 1,2-dibromo-3-chloropropane, and methyl isothiocyanate. Biological activity of soil fumigants ranges from limited to broad spectrum. Fumigants diffuse through the continuous soil air space as gases. Physical and chemical characteristics determine diffusion rates, distribution between the soil air and moisture, and sorption onto and into the soil particles. The principal soil factors affecting the efficacy of each treatment are the size and continuity of air space, moisture, temperature, organic matter, and depth of placement. Application can be made overall with tractor injection or plow-sole, or as a row or bed treatment. Treatment for trees is best made in conjunction with tree site backhoeing. PMID:19287772

Lembright, H. W.

1990-01-01

413

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

414

Microtribological Performance of Metal-doped Molybdenum Disulfide Coatings  

NASA Astrophysics Data System (ADS)

The mechanical and tribological properties of pure MoS2, pure Au, Au-MoS2 and Ti-MoS2 coatings were evaluated and examined at a microscopic scale. The metal doped MoS2 coatings had varying metal content, 5-10at% for Ti and 10-90% for Au. Reciprocating sliding wear tests were performed with a range of initial Hertzian contact pressures from 0.41 to 3.5 GPa and in air at two humidity levels (i.e. "low" being 3-5%RH and "high" being 30-40%RH). Titanium and gold were chosen for this study as metal additives due to their positive influence on the mechanical properties of the coating. The friction and wear behavior at the micro-scale were directly compared to tribological properties at the macro-scale, which were performed using an in situ tribometer. Reciprocating micro- and macro- wear tests were performed with spherical diamond tip (with 10 and 50 mum radii) and a sapphire tip (with a radius of 3.175 mm), respectively. The range of initial Hertzian contact pressures for macro-scale (i.e. between 0.41GPa and 1.2GPa) overlapped with that for micro-scale. However, the initial Hertzian contact diameters (2*a) were very different (i.e. 0.8-2.3 mum for micro-scale and 60-180 mum for macro-scale). It was observed that the small addition of Ti or Au to MoS2 improved the microtribological properties (i.e. lower friction and less wear) compared to pure MoS2 coatings. The improved microtribological properties with metal additions were attributed to an increase in the mechanical properties, decrease in adhesion, and a decrease in the interfacial shear strength. In terms of the different length scales, lower steady state friction was observed for macrotribology compared to microtribology. The higher friction at the micro- scale was explained by the greater adhesion effects and additional velocity accommodation modes (e.g. microplowing or plowing). The microplowing or plowing at the microscopic scale was attributed to the tip roughness and the inability to sustain a stable transferfilm throughout the tests at high humidity. In addition, using in situ and ex situ techniques, three different stages for solid lubrication were identified based on differences in contact area, tip shapes, and environmental conditions. The first stage has been previously observed with macrotribology on MoS 2 coatings at low humidity levels. The second stage, on the other hand, was observed for micro-tribology where the contact size is significantly smaller compared to stage one. The main wear mechanism is still adhesion, but there is also some micro-plowing. The final stage was observed for humid sliding in microtribology, where no transfer films were observed and therefore the main wear mechanism was plowing.

Stoyanov, Pantcho

2011-07-01

415

Friction and wear characteristics of iron-chromium alloys in contact with themselves and silicon carbide  

NASA Technical Reports Server (NTRS)

Sliding friction experiments were conducted with various iron-chromium alloys in contact with (1) themselves, (2) single crystal silicon carbide disks, and (3) single crystal abrasive grit of silicon carbide. Results indicate the coefficients of friction for the alloys sliding against themselves are between those for pure iron and pure chromium, and are only slightly different with 1, 5, 9, 14, and 19 weight percent chromium in iron. The wear is due, primarily, to shearing, or tearing fracture, of the cohesive bonds in the bulk metal and plowing of the bulk by lumps of wear debris. There are only slight differences in the coefficients of friction for the various alloys when sliding on silicon carbide. The coefficient of friction for the alloys are higher than those for pure iron and pure chromium. Alloy hardening observed in the alloys plays a dominant role in controlling the abrasive friction and wear behavior of the alloys.

Miyoshi, K.; Buckley, D. H.

1979-01-01

416

An unremembered diversity: mixed husbandry and the American grasslands.  

PubMed

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

417

Investigation of spatial distribution of radiocesium in a paddy field as a potential sink.  

PubMed

Surface soils, under various land uses, were contaminated by radionuclides that were released by the Fukushima Daiichi Nuclear Power Plant accident. Because paddy fields are one of the main land uses in Japan, we investigated the spatial distribution of radiocesium and the influence of irrigation water in a paddy field during cultivation. Soil core samples collected at a paddy field in Fukushima showed that plowing had disturbed the original depth distribution of radiocesium. The horizontal distribution of radiocesium did not show any evidence for significant influence of radiocesium from irrigation water, and its accumulation within the paddy field, since the original amount of radiocesium was much larger than was added into the paddy field by irrigation water. However, it is possible that rainfall significantly increases the loading of radiocesium. PMID:24260481

Tanaka, Kazuya; Iwatani, Hokuto; Takahashi, Yoshio; Sakaguchi, Aya; Yoshimura, Kazuya; Onda, Yuichi

2013-01-01

418

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

419

Semi-automatic crop inventory from sequential ERTS-1 imagery  

NASA Technical Reports Server (NTRS)

The detection of a newly introduced crop into the Imperial (California) Valley by sequential ERTS-1 imagery is proving that individual crop types can be identified by remote sensing techniques. Initial results have provided an extremely useful product for water agencies. A system for the identification of field conditions enables the production of a statistical summary within two to three days of receipt of the ERTS-1 imagery. The summary indicates the total acreage of producing crops and irrigated planted crops currently demanding water and further indicates freshly plowed fields that will be demanding water in the near future. Relating the field conditions to the crop calendar of the region by means of computer techniques will provide specific crop identification for the 8000 plus fields.

Johnson, C. W.; Coleman, V. B.

1973-01-01

420

Evaluation of remote sensing in control of pink bollworm in cotton. [Southern California deserts  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The main objective is to evaluate the use of a satellite in monitoring the cotton production regulation program of the State of California as an aid in controlling pink bollworm infestation in the southern deserts of California. Color combined images of ERTS-1 multispectral images simulating color infrared are being used for crop identification. The status of each field (i.e., crop, bare, harvested, wet, plowed) is mapped from the imagery and is then compared to ground survey information taken at the time of ERTS-1 overflights. A computer analysis has been performed to compare field and satellite data to a crop calendar. Correlation to data has been 97% for field condition. Actual crop identification varies; cotton identification is only 63% due to lack of full season coverage.

Lewis, L. N. (principal investigator); Coleman, V. B.

1973-01-01

421

Evaluation of remote sensing in control of pink bollworm in cotton. [Imperial Valley, Coachella Valley, and Palo Verde Valley, California  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. This investigation is to evaluate the use of a satellite in monitoring the cotton production regulation program of the State of California as an aid in controlling pink bollworm infestation in the southern deserts of California. Color combined images of ERTS-1 multispectral images simulating color infrared are being used for crop identification. The status of each field (crop, bare, harvested, wet, plowed) is mapped from the imagery and is then compared to ground survey information taken at the time of ERTS-1 overflights. A computer analysis has been performed to compare field and satellite data to a crop calendar. Correlation to date has been 97% for field condition. Actual crop identification varies; cotton identification is only 63% due to lack of full season coverage.

Lewis, L. N. (principal investigator); Coleman, V. B.; Johnson, C. W.

1974-01-01

422

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

423

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

424

"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

425

Effect of errors in positioning the sampling points on the assessment of the relationships between the remote sensing data and the soil properties  

NASA Astrophysics Data System (ADS)

The stochastic modeling of the shift in coordinates of the sampling points was performed for a typical land plot in Bryansk opolie with the purpose to assess the influence of the accuracy of the sampling point positioning on the predicted properties of the plow horizon. It was proved that, for agro-gray soils, an occasional shift of the sampling points by 2-6 m regarding the coordinates on satellite photographs of superhigh resolution may significantly change the correlation between the soil properties and the brightness in the infrared channel. Based on the modeling data, the 95% confidence interval was estimated for the possible correlation coefficients of such properties of the arable agro-gray soil as the density, moisture, specific surface, carbon, and mobile nitrogen content. The use of the brightness in the infrared channel as a covariate for building charts may noticeably improve the map's quality; however, it may unjustifiably complicate the mapping units delineation.

Samsonova, V. P.; Meshalkina, Yu. L.; Blagoveshchenskii, Yu. N.

2013-05-01

426

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

427

Brine release based on structural calculations of damage around an excavation at the Waste Isolation Pilot Plant (WIPP)  

SciTech Connect

In a large in situ experimntal circular room, brine inflow was measured over 5 years. After correcting for evaporation losses into mine ventilation air, the measurements gave data for a period of nearly 3 years. Predicted brine accumulation based on a mechanical ``snow plow`` model of the volume swept by creep-induced damage as calculated with the Multimechanism Deformation Coupled Fracture model was found to agree with experiment. Calculation suggests the damage zone at 5 years effectively exends only some 0.7 m into the salt around the room. Also, because the mecahnical model of brine release gives an adequate explanation of the measured data, the hydrological process of brine flow appears to be rapid compared to the mechanical process of brine release.

Munson, D.E.; Jensen, A.L.; Webb, S.W. [Sandia National Labs., Albuquerque, NM (United States); DeVries, K.L. [RE/SPEC, Inc., Rapid City, SD (United States)

1996-02-01

428

Impact of reclamation treatment on the biological activity of soils of the solonetz complex in Western Siberia  

NASA Astrophysics Data System (ADS)

The abundance and activity of the soil microflora were studied in a field experiment with the use of green manure crops to assess the impact of reclamation measures on the biological activity of soils of the solonetz complex. The number of microorganisms in the plow soil horizon increased in the background of the green fallows as compared to the black ones. Coefficients of mineralization, immobilization, and transformation of organic compounds were calculated for different variants of the soil treatment. The value of the mineralization coefficient indicates the intense decomposition of the green manure that entered the soil. In the first year, peas were actively decomposed, while oats, in the second year (aftereffect). The activity of the soil enzymes (invertase, urease, and catalase) was determined. A close relationship between the catalase activity and the intensity of the microbiological processes in the soils was revealed.

Berezin, L. V.; Khamova, O. F.; Paderina, E. V.; Gindemit, A. M.

2014-11-01

429

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

430

[Distribution characteristics of soil humus fractions stable carbon isotope natural abundance (delta 13C) in paddy field under long-term ridge culture].  

PubMed

A 16-year field experiment was conducted in a ridge culture paddy field in the hilly region of Sichuan Basin, aimed to investigate the distribution characteristics of stable carbon isotope natural abundance (delta 13C) in soil humus fractions. The soil organic carbon (SOC) content in the paddy field under different cultivation modes ranked in the order of wide ridge culture > ridge culture > paddy and upland rotation. In soil humus substances (HS), humin (HU) was the main composition, occupying 21% - 30% of the total SOC. In the extracted soil carbon, humic acid (HA) dominated, occupying 17% - 21% of SOC and 38% - 65% of HS. The delta 13C value of SOC ranged from -27.9 per thousand to -25.6 per thousand, and the difference of the delta 13C value between 0-5 cm and 20-40 cm soil layers was about 1.9 per thousand. The delta 13C value of HA under different cultivation modes was 1 per thousand - 2 per thousand lower than that of SOC, and more approached to the delta 13C value of rapeseed and rice residues. As for fulvic acid (FA), its delta 13C value was about 2 per thousand and 4 per thousand higher than that of SOC and HA, respectively. The delta 13C value of HU in plough layer (0-20 cm) and plow layer (20-40 cm) ranged from -23.7 per thousand - -24.9 per thousand and -22.6 per thousand - -24.2 per thousand, respectively, reflecting the admixture of young and old HS. The delta 13C value in various organic carbon fractions was HU>FA>SOC>rapeseed and rice residues>HA. Long-term rice planting benefited the increase of SOC content, and cultivation mode played an important role in affecting the distribution patterns of soil humus delta 13C in plough layer and plow layer. PMID:21774322

Tang, Xiao-hong; Luo, You-jin; Ren, Zhen-jiang; Lü, Jia-ke; Wei, Chao-fu

2011-04-01

431

Standardization of a Volumetric Displacement Measurement for Two-Body Abrasion Scratch Test Data Analysis  

NASA Technical Reports Server (NTRS)

A limitation has been identified in the existing test standards used for making controlled, two-body abrasion scratch measurements based solely on the width of the resultant score on the surface of the material. A new, more robust method is proposed for analyzing a surface scratch that takes into account the full three-dimensional profile of the displaced material. To accomplish this, a set of four volume- displacement metrics was systematically defined by normalizing the overall surface profile to denote statistically the area of relevance, termed the Zone of Interaction. From this baseline, depth of the trough and height of the plowed material are factored into the overall deformation assessment. Proof-of-concept data were collected and analyzed to demonstrate the performance of this proposed methodology. This technique takes advantage of advanced imaging capabilities that allow resolution of the scratched surface to be quantified in greater detail than was previously achievable. When reviewing existing data analysis techniques for conducting two-body abrasive scratch tests, it was found that the ASTM International Standard G 171 specified a generic metric based only on visually determined scratch width as a way to compare abraded materials. A limitation to this method was identified in that the scratch width is based on optical surface measurements, manually defined by approximating the boundaries, but does not consider the three-dimensional volume of material that was displaced. With large, potentially irregular deformations occurring on softer materials, it becomes unclear where to systematically determine the scratch width. Specifically, surface scratches on different samples may look the same from a top view, resulting in an identical scratch width measurement, but may vary in actual penetration depth and/or plowing deformation. Therefore, two different scratch profiles would be measured as having identical abrasion properties, although they differ significantly.

Street, K. W. Jr.; Kobrick, R. L.; Klaus, D. M.

2011-01-01

432

Responses of Active Bacterial and Fungal Communities in Soils under Winter Wheat to Different Fertilizer and Pesticide Regimens  

PubMed Central

The composition of the active microbial (bacterial and fungal) soil community in an arable wheat field subjected to different management practices was examined at five times during a 1-year period. Field sections were fertilized either at good agricultural practice (GAP) levels or at reduced levels (0.5× GAP) and were inoculated with vesicular arbuscular mycorrhizae (VAM) at the same time. Field subsections were treated either with or without pesticides. Changes in the active microbial communities were investigated by denaturing gradient gel electrophoresis analysis of reverse transcription-PCR-amplified 16S and 18S rRNA. Microbial community structure was primarily determined by season, and the seasonal trends were similar for the fungal and bacterial components. Between-sample microbial heterogeneity decreased under a mature crop in the summer but increased following harvesting and plowing. Although similar overall trends were seen for the two microbial components, sample variability was greater for the fungal community than for the bacterial community. The greatest management effects were due to GAP fertilization, which caused increases in the bacterial numbers in the total and culturable communities. Microbial biomass similarly increased. GAP fertilization also caused large shifts in both the active bacterial community structure and the active fungal community structure and additionally resulted in a decrease in the heterogeneity of the active bacterial community. Pesticide addition did not significantly affect bacterial numbers or heterogeneity, but it led to major shifts in the active soil bacterial community structure. PCR primers specific for Glomales 25S rRNA genes were used to monitor the VAM population following inoculation. Glomales were detected initially only in VAM-inoculated field sections but were subsequently detected in noninoculated field sections as the season progressed. After plowing, the level of Glomales was reduced in noninoculated field sections but remained high in VAM-inoculated field sections. Inoculation of VAM correlated with elevated soil phosphate and carbon levels. PMID:15128520

Girvan, Martina S.; Bullimore, Juliet; Ball, Andrew S.; Pretty, Jules N.; Osborn, A. Mark

2004-01-01

433

Sediment losses and gains across a gradient of livestock grazing and plant invasion in a cool, semi-arid grassland, Colorado Plateau, USA  

USGS Publications Warehouse

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. ?? 2009 Elsevier B.V. All rights reserved.

Belnap, J.; Reynolds, R.L.; Reheis, M.C.; Phillips, S.L.; Urban, F.E.; Goldstein, H.L.

2009-01-01

434

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

435

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, Amélie; Wolfsteiner, Ulrike; Schuster, Frank; Wunder, Christian; Kranke, Peter; Roewer, Norbert; Brederlau, Jörg

2008-01-01

436

Avian influenza survey in migrating waterfowl in Sonora, Mexico.  

PubMed

A two-year survey was carried out on the occurrence of avian influenza in migrating birds in two estuaries of the Mexican state of Sonora, which is located within the Pacific flyway. Cloacal and oropharyngeal swabs were collected from 1262 birds, including 20 aquatic bird species from the Moroncarit and Tobari estuaries in Sonora, Mexico. Samples were tested for type A influenza (M), H5 Eurasian and North American subtypes (H5EA and H5NA respectively) and the H7 North American subtype (H7NA). Gene detection was determined by one-step real-time reverse transcription polymerase chain reaction (RRT-PCR). The results revealed that neither the highly pathogenic avian influenza virus H5 of Eurasian lineage nor H7NA were detected. The overall prevalence of avian influenza type A (M-positive) in the sampled birds was 3.6% with the vast majority in dabbling ducks (Anas species). Samples from two birds, one from a Redhead (Aythya americana) and another from a Northern Shoveler (Anas clypeata), were positive for the low-pathogenic H5 avian influenza virus of North American lineage. These findings represented documented evidence of the occurrence of avian influenza in wintering birds in the Mexican wetlands. This type of study contributes to the understanding of how viruses spread to new regions of North America and highlights the importance of surveillance for the early detection and control of potentially pathogenic strains, which could affect animal and human health. PMID:21091641

Montalvo-Corral, M; López-Robles, G; Hernández, J

2011-02-01

437

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

438

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

439

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

440

Real -time dispatching modelling for trucks with different capacities in open pit mines / Modelowanie w czasie rzeczywistym przewozów ci??arówek o ró?nej ?adowno?ci w kopalni odkrywkowej  

NASA Astrophysics Data System (ADS)

Application of fully automated systems for truck dispatching plays a major role in decreasing the transportation costs which often represent the majority of costs spent on open pit mining. Consequently, the application of a truck dispatching system has become fundamentally important in most of the world's open pit mines. Recent experiences indicate that by decreasing a truck's travelling time and the associated waiting time of its associated shovel then due to the application of a truck dispatching system the rate of production will be considerably improved. Computer-based truck dispatching systems using algorithms, advanced and accurate software are examples of these innovations. Developing an algorithm of a computer- based program appropriated to a specific mine's conditions is considered as one of the most important activities in connection with computer-based dispatching in open pit mines. In this paper the changing trend of programming and dispatching control algorithms and automation conditions will be discussed. Furthermore, since the transportation fleet of most mines use trucks with different capacities, innovative methods, operational optimisation techniques and the best possible methods for developing the required algorithm for real-time dispatching are selected by conducting research on mathematical-based planning methods. Finally, a real-time dispatching model compatible with the requirement of trucks with different capacities is developed by using two techniques of flow networks and integer programming.

Ahangaran, Daryoush Kaveh; Yasrebi, Amir Bijan; Wetherelt, Andy; Foster, Patrick

2012-10-01

441

Fine structure and functional comments of mouthparts in Platypus cylindrus (Col., Curculionidae: Platypodinae).  

PubMed

Oak pinhole borer, Platypus cylindrus is seen in recent years as one of the biggest enemies directly involved in the observed decline of cork oak in Mediterranean forests with all the economic implications. As an ambrosia beetle, it has developed its effective drilling mouthpart enough to make tunnels in hardwood of the tree. The fine structural aspects of the mouthpart using the field emission scanning electron microscopy are analyzed about 23 adults collected in galleries of infested cork oak trees (Quercus suber) in a littoral forest of northwest Algeria. These adults are preserved in alcohol 70%, cleaned and coated with gold. The mouthparts of this beetle consist commonly of a labrum, a pair of mandibles, a pair of maxillae and the labium but with adapted structure to excavate galleries in the hardwood. In this role is also involved the first pair of legs. The function that present the different structures related to the construction of the tunnels is discussed. Both of maxillary and labial palpi direct the food to the mouth and hold it while the mandibles chew the food. The distal ends of these palpi are flattened and have shovel-like setae. Females have larger maxillary palpi than males and this is related to the particular biology of each sex. PMID:23182681

Belhoucine, Latifa; Bouhraoua, Rachid T; Prats, Eva; Pulade-Villar, Juli

2013-02-01

442

The opossum (Didelphis virginiana) as a host for Sarcocystis debonei from cowbirds (Molothrus ater) and grackles (Cassidix mexicanus, Quiscalus quiscula).  

PubMed

Sarcocystis-infected muscles from ducks, cowbirds, and grackles were fed to cats, opossums, rats, and a dog. Only the opossum (Didelphis virginiana) was a suitable definitive host. All opossums that were fed Sarcocystis-infected cowbirds (Molothrus ater) and grackles (Cassidix mexicanus and Quiscalus quiscula) passed sporocysts in their feces. Opossums that ate the cowbirds had prepatent periods of 5 and 10 days and remained patent for at least 105 days. Opossums that ate the grackles became patent on day 10 after the infective meal and remained patent for over 90 (Quiscalus) and 105 (Cassidix) days. A single opossum fed infected muscle from a pintail duck (Anas acuta) passed sporocysts in the feces from days 13 through 18 after infection. No sporocysts were passed by opossums fed infected muscle from the green-winged teal (Anas carolinensis) and shoveller (Spatula clypeata). Sporocysts of duck, cowbird, and grackle origin were structurally similar. Mean dimensions of sporocysts were: duck-origin, 11.2 by 8.2 micron; cowbird-origin, 11.4 by 7.8 micron; Cassidix-origin, 11.2 by 7.8 micron; and Quiscalus-origin, 11.6 by 7.7 micron. We designate the sporocysts of cowbird and grackle origin as Sarcoycstis debonei Vogelsang, 1929 (Syn. Isospora boughtoni Volk, 1938). PMID:417165

Duszynski, D W; Box, E D

1978-04-01

443

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

444

Whole body vibration exposure in heavy earth moving machinery operators of metalliferrous mines.  

PubMed

As mining operations get mechanized, the rate of profit generation increases and so do the rate of occupational hazards. This study deals with one such hazard - occupational vibration. The present study was carried out to determine the whole body vibration (WBV) exposure of the heavy earth moving machinery (HEMM) operators in two types of metalliferous mines in India, when they were engaged in the mining activity. Cross-comparison was done of the vibration dose value (VDV) for HEMM operators as well as each type of mine. The VDV for the shovel operator in bauxite mine was observed to be 13.53 +/- 5.63 m/s(7/4) with 25% of the readings higher than the prescribed limit whereas in iron ore mine VDV for dumper operator was 10.81 +/- 3.44 m/s(7/4) with 14.62% readings on the higher side. Cross-comparison of the VDV values for bauxite and iron ore mines revealed that it was 9.57 +/- 4.93 and 8.21 +/- 5.12 m/s(7/4) with 21.28 and 14.95% of the readings on the higher side respectively. The Student's t test level was found to be insignificant for both type of mines, indicating that the WBV exposure is not dependent on the type of mine but is dependent on the working condition and type of HEMM in operation. PMID:17874194

Vanerkar, A P; Kulkarni, N P; Zade, P D; Kamavisdar, A S

2008-08-01

445

Interspecies transmission and limited persistence of low pathogenic avian influenza genomes among Alaska dabbling ducks.  

PubMed

The reassortment and geographic distribution of low pathogenic avian influenza (LPAI) virus genes are well documented, but little is known about the persistence of intact LPAI genomes among species and locations. To examine persistence of entire LPAI genome constellations in Alaska, we calculated the genetic identities among 161 full-genome LPAI viruses isolated across 4 years from five species of duck: northern pintail (Anas acuta), mallard (Anas platyrhynchos), American green-winged teal (Anas crecca), northern shoveler (Anas clypeata) and American wigeon (Anas americana). Based on pairwise genetic distance, highly similar LPAI genomes (>99% identity) were observed within and between species and across a range of geographic distances (up to and >1000 km), but most often between isolates collected 0-10 km apart. Highly similar viruses were detected between years, suggesting inter-annual persistence, but these were rare in our data set with the majority occurring within 0-9 days of sampling. These results identify LPAI transmission pathways in the context of species, space and time, an initial perspective into the extent of regional virus distribution and persistence, and insight into why no completely Eurasian genomes have ever been detected in Alaska. Such information will be useful in forecasting the movement of foreign-origin avian influenza strains should they be introduced to North America. PMID:21964597

Reeves, Andrew B; Pearce, John M; Ramey, Andrew M; Meixell, Brandt W; Runstadler, Jonathan A

2011-12-01

446

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

447

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

448

Idiosyncratic Responses of High Arctic Plants to Changing Snow Regimes  

PubMed Central

The Arctic is one of the ecosystems most affected by climate change; in particular, winter temperatures and precipitation are predicted to increase with consequent changes to snow cover depth and duration. Whether the snow-free period will be shortened or prolonged depends on the extent and temporal patterns of the temperature and precipitation rise; resulting changes will likely affect plant growth with cascading effects throughout the ecosystem. We experimentally manipulated snow regimes using snow fences and shoveling and assessed aboveground size of eight common high arctic plant species weekly throughout the summer. We demonstrated that plant growth responded to snow regime, and that air temperature sum during the snow free period was the best predictor for plant size. The majority of our studied species showed periodic growth; increases in plant size stopped after certain cumulative temperatures were obtained. Plants in early snow-free treatments without additional spring warming were smaller than controls. Response to deeper snow with later melt-out varied between species and categorizing responses by growth forms or habitat associations did not reveal generic trends. We therefore stress the importance of examining responses at the species level, since generalized predictions of aboveground growth responses to changing snow regimes cannot be made. PMID:24523859

Rumpf, Sabine B.; Semenchuk, Philipp R.; Dullinger, Stefan; Cooper, Elisabeth J.

2014-01-01

449

Level II Cultural Resource investigation for the Texoma Distribution Enhancements project, Cameron and Calcasieu Parishes, Louisiana: Final report  

SciTech Connect

A Level II Cultural Resource Survey was completed for the Texoma Distribution Enhancements project, located in Cameron and Calcasieu Parishes, Louisiana. The 13-mile pipeline extends from Strategic Petroleum Reserve No. 3 to a terminus near Vincent Landing. Located in Louisiana's southwest coastal zone, the pipeline will traverse extensive marsh lands as well as upland prairie terrace areas. Present land use within the project area consists primarily of undeveloped marsh land and cattle range. The study methods included background research, intensive pedestrian survey with systematic shovel testing, a boat survey, and laboratory analysis of recovered artifact collections. One historic site, 16CU205, was identified during the field survey, and it was tested for National Register eligibility. The site is assignable to the Industrialization and Modernization (1890-1940) Cultural Unit. Archaeological testing indicates that it is a rural residence or farmstead, with a house and one outbuilding within the proposed right-of-way. The site lacks significant historical association and sufficient archaeological integrity to merit inclusion on the National Register of Historic Places. Four standing structures were also identified during the field survey. The structures are agricultural outbuildings, less than 40 years in age, that possess no architectural distinction or historical association. They have been documented photographically and by scaled plan drawings, but do not merit additional study prior to their destruction. 24 refs., 15 figs., 3 tabs.

LeeDecker, C. H.; Holland, C. C.

1987-10-01

450

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

451

Influenza A viruses in wild birds of the Pacific flyway, 2005-2008.  

PubMed

Avian influenza viruses (AIVs) pose a significant threat to public health, and viral subtypes circulating in natural avian reservoirs can contribute to the emergence of pathogenic influenza viruses in humans. We investigated the prevalence and distribution of AIVs in 8826 migratory and resident wild birds in North America along the Pacific flyway, which is a major north-south migration pathway that overlaps with four other flyways in Alaska providing opportunities for mixing of Eurasian and American origin influenza viruses. Overall, the prevalence of AIVs was low (1%) among the wide range of avian species tested, but we detected AIVs in 69 hunter-harvested waterfowl (Anseriformes) sampled at a national wildlife refuge in California from October 2007 to January 2008. A wide range of subtypes were detected in waterfowl with H6N1, H10N7, H7N3, and H3N5 being the most common. We suspect H6N1 was introduced or remerged in 2007 at this key wintering site for waterfowl along the Pacific Flyway. Over a 3-week period, 13 H6N1 AIVs were isolated from two northern pintails (Anas acuta), three northern shovelers (Anas clypeata), three ring-necked ducks (Aythya collaris), four American widgeon (Anas americana), and one gadwall (Anas strepera). We conclude that a diverse array of AIVs was present and that cross-species transmission was occurring among waterfowl in the central valley wetlands of California. PMID:20059316

Siembieda, Jennifer L; Johnson, Christine K; Cardona, Carol; Anchell, Nichole; Dao, Nguyet; Reisen, William; Boyce, Walter

2010-10-01

452

Improving waterfowl production estimates: results of a test in the prairie pothole region  

USGS Publications Warehouse

The U.S. Fish and Wildlife Service in an effort to improve and standardize methods for estimating waterfowl production tested a new technique in the four-county Arrowwood Wetland Management District (WMD) for three years (1982-1984). On 14 randomly selected 10.36 km2 plots, upland and wetland habitat was mapped, classified, and digitized. Waterfowl breeding pairs were counted twice each year and the proportion of wetland basins containing water was determined. Pair numbers and habitat conditions were entered into a computer model developed by Northern Prairie Wildlife Research Center. That model estimates production on small federally owned wildlife tracts, federal wetland easements, and private land. Results indicate that production estimates were most accurate for mallards (Anas platyrhynchos), the species for which the computer model and data base were originally designed. Predictions for the pintail (Anas acuta), gadwall (A. strepa), blue-winged teal (A. discors), and northern shoveler (A. clypeata) were believed to be less accurate. Modeling breeding period dynamics of a waterfowl species and making credible production estimates for a geographic area are possible if the data used in the model are adequate. The process of modeling the breeding period of a species aids in locating areas of insufficient biological knowledge. This process will help direct future research efforts and permit more efficient gathering of field data.

Arnold, P.M.; Cowardin, L.M.

1985-01-01

453

Interspecies transmission and limited persistence of low pathogenic avian influenza genomes among Alaska dabbling ducks  

USGS Publications Warehouse

The reassortment and geographic distribution of low pathogenic avian influenza (LPAI) virus genes are well documented, but little is known about the persistence of intact LPAI genomes among species and locations. To examine persistence of entire LPAI genome constellations in Alaska, we calculated the genetic identities among 161 full-genome LPAI viruses isolated across 4 years from five species of duck: northern pintail (Anas acuta), mallard (Anas platyrhynchos), American green-winged teal (Anas crecca), northern shoveler (Anas clypeata) and American wigeon (Anas Americana). Based on pairwise genetic distance, highly similar LPAI genomes (>99 percent identity) were observed within and between species and across a range of geographic distances (up to and >1000 km), but most often between isolates collected 0-10 km apart. Highly similar viruses were detected between years, suggesting inter-annual persistence, but these were rare in our data set with the majority occurring within 0-9 days of sampling. These results identify LPAI transmission pathways in the context of species, space and time, an initial perspective into the extent of regional virus distribution and persistence, and insight into why no completely Eurasian genomes have ever been detected in Alaska. Such information will be useful in forecasting the movement of foreign-origin avian influenza strains should they be introduced to North America.

Reeves, Andrew; Pearce, John; Ramey, Andy M.; Meixell, Brandt; Runstadler, Jonathan A.

2011-01-01

454

Interspecies transmission and limited persistence of low pathogenic avian influenza genomes among Alaska dabbling ducks  

USGS Publications Warehouse

The reassortment and geographic distribution of low pathogenic avian influenza (LPAI) virus genes are well documented, but little is known about the persistence of intact LPAI genomes among species and locations. To examine persistence of entire LPAI genome constellations in Alaska, we calculated the genetic identities among 161 full-genome LPAI viruses isolated across 4. years from five species of duck: northern pintail (Anas acuta), mallard (Anas platyrhynchos), American green-winged teal (Anas crecca), northern shoveler (Anas clypeata) and American wigeon (Anas americana). Based on pairwise genetic distance, highly similar LPAI genomes (>99% identity) were observed within and between species and across a range of geographic distances (up to and >1000 km), but most often between isolates collected 0-10. km apart. Highly similar viruses were detected between years, suggesting inter-annual persistence, but these were rare in our data set with the majority occurring within 0-9. days of sampling. These results identify LPAI transmission pathways in the context of species, space and time, an initial perspective into the extent of regional virus distribution and persistence, and insight into why no completely Eurasian genomes have ever been detected in Alaska. Such information will be useful in forecasting the movement of foreign-origin avian influenza strains should they be introduced to North America. ?? 2011.

Reeves, A.B.; Pearce, J.M.; Ramey, A.M.; Meixell, B.W.; Runstadler, J.A.

2011-01-01

455

Phylogenetic and pathogenic analyses of three H5N1 avian influenza viruses (clade 2.3.2.1) isolated from wild birds in Northeast China.  

PubMed

From April to September 2012, periodic surveillance of avian influenza H5N1 viruses from different wild bird species was conducted in Northeast China. Three highly pathogenic avian influenza (HPAI) H5N1 viruses were isolated from a yellow-browed warbler, common shoveler, and mallard. To trace the genetic lineage of the isolates, nucleotide sequences of all eight gene segments were determined and phylogenetically analyzed. The data indicated that three viruses belonged to the same antigenic virus group: clade 2.3.2.1. To investigate the pathogenicity of these three viruses in different hosts, chickens, ducks, and mice were inoculated. The results showed that chickens were susceptible to each of the three HPAI H5N1 viruses, resulting in 100% mortality within 2-6days after infection, whereas the three isolates exhibited distinctly different virulence in ducks and mice. The results of this study demonstrated that HPAI H5N1 viruses of clade 2.3.2.1 are still circulating in wild birds through overlapping migratory flyways. Therefore, continuous monitoring of H5N1 in both domestic and wild birds is necessary to prevent a potentially wider outbreak. PMID:25461692

Fan, Zhaobin; Ci, Yanpeng; Liu, Liling; Ma, Yixin; Jia, Ying; Wang, Deli; Guan, Yuntao; Tian, Guobin; Ma, Jianzhang; Li, Yanbing; Chen, Hualan

2015-01-01

456

The Mousterian child from Teshik-Tash is a Neanderthal: a geometric morphometric study of the frontal bone.  

PubMed

In the 1930s subadult hominin remains and Mousterian artifacts were discovered in the Teshik-Tash cave in South Uzbekistan. Since then, the majority of the scientific community has interpreted Teshik-Tash as a Neanderthal. However, some have considered aspects of the morphology of the Teshik-Tash skull to be more similar to fossil modern humans such as those represented at Skh?l and Qafzeh, or to subadult Upper Paleolithic modern humans. Here we present a 3D geometric morphometric analysis of the Teshik-Tash frontal bone in the context of developmental shape changes in recent modern humans, Neanderthals, and early modern humans. We assess the phenetic affinities of Teshik-Tash to other subadult fossils, and use developmental simulations to predict possible adult shapes. We find that the morphology of the frontal bone places the Teshik-Tash child close to other Neanderthal children and that the simulated adult shapes are closest to Neanderthal adults. Taken together with genetic data showing that Teshik-Tash carried mtDNA of the Neanderthal type, as well as its occipital bun, and its shovel-shaped upper incisors, these independent lines of evidence firmly place Teshik-Tash among Neanderthals. PMID:22976750

Gunz, Philipp; Bulygina, Ekaterina

2012-11-01

457

Locomotor benefits of being a slender and slick sand swimmer.  

PubMed

Squamates classified as 'subarenaceous' possess the ability to move long distances within dry sand; body elongation among sand and soil burrowers has been hypothesized to enhance subsurface performance. Using X-ray imaging, we performed the first kinematic investigation of the subsurface locomotion of the long, slender shovel-nosed snake (Chionactis occipitalis) and compared its biomechanics with those of the shorter, limbed sandfish lizard (Scincus scincus). The sandfish was previously shown to maximize swimming speed and minimize the mechanical cost of transport during burial. Our measurements revealed that the snake also swims through sand by propagating traveling waves down the body, head to tail. Unlike the sandfish, the snake nearly followed its own tracks, thus swimming in an approximate tube of self-fluidized granular media. We measured deviations from tube movement by introducing a parameter, the local slip angle, ?s, which measures the angle between the direction of movement of each segment and body orientation. The average ?s was smaller for the snake than for the sandfish; granular resistive force theory (RFT) revealed that the curvature utilized by each animal optimized its performance. The snake benefits from its slender body shape (and increased vertebral number), which allows propagation of a higher number of optimal curvature body undulations. The snake's low skin friction also increases performance. The agreement between experiment and RFT combined with the relatively simple properties of the granular 'frictional fluid' make subarenaceous swimming an attractive system to study functional morphology and bauplan evolution. PMID:25524983

Sharpe, Sarah S; Koehler, Stephan A; Kuckuk, Robyn M; Serrano, Miguel; Vela, Patricio A; Mendelson, Joseph; Goldman, Daniel I

2015-02-01

458

The effectiveness of resistive force theory in granular locomotiona)  

NASA Astrophysics Data System (ADS)

Resistive force theory (RFT) is often used to analyze the movement of microscopic organisms swimming in fluids. In RFT, a body is partitioned into infinitesimal segments, each of which generates thrust and experiences drag. Linear superposition of forces from elements over the body allows prediction of swimming velocities and efficiencies. We show that RFT quantitatively describes the movement of animals and robots that move on and within dry granular media (GM), collections of particles that display solid, fluid, and gas-like features. RFT works well when the GM is slightly polydisperse, and in the "frictional fluid" regime such that frictional forces dominate material inertial forces, and when locomotion can be approximated as confined to a plane. Within a given plane (horizontal or vertical) relationships that govern the force versus orientation of an elemental intruder are functionally independent of the granular medium. We use the RFT to explain features of locomotion on and within granular media including kinematic and muscle activation patterns during sand-swimming by a sandfish lizard and a shovel-nosed snake, optimal movement patterns of a Purcell 3-link sand-swimming robot revealed by a geometric mechanics approach, and legged locomotion of small robots on the surface of GM. We close by discussing situations to which granular RFT has not yet been applied (such as inclined granular surfaces), and the advances in the physics of granular media needed to apply RFT in such situations.

Zhang, Tingnan; Goldman, Daniel I.

2014-10-01

459

High volume-high value usage of flue gas desulfurization (FGD) by-products in underground mines: Phase 2 -- Field investigations. Quarterly report, October 1--December 31, 1997  

SciTech Connect

The field investigation phase of the project was essentially completed when grout placed into auger holes at the Lodestar Energy mine site during Summer 1997 was sampled. Mining had proceeded to a point where the strata overlying the coal was completely removed, thus exposing the grout-filled auger holes. All of the auger holes contained either grout from these experiments or shale that in-filled the non-grouted holes during the process of clearing the top surface of the coal. Eleven grouted holes were sampled, utilizing hammers and chisels, for physical (strength) testing, as well as chemical, mineralogical, and microscopical analysis. Upon arrival at the laboratory, moisture contents, densities, and void ratios were obtained before disturbing the samples, and after strength testing. Representative samples of each grout were then cut into flat-sided prisms, with a height:width ratio {approx}2, to be used for testing of unconfined compressive strength. In summary, all of the grouts had very good mechanical strength, ranging from 1000 psi to 2250 psi. The lowest compressive strength was recorded on a bed ash-based grout.

NONE

1998-08-01

460

Feasibility of Piezoelectric Endoscopic Transsphenoidal Craniotomy: A Cadaveric Study  

PubMed Central

Objective. Endoscopic transsphenoidal approach has become the gold standard for surgical treatment of treating pituitary adenomas or other lesions in that area. Opening of bony skull base has been performed with burrs, chisels, and hammers or standard instruments like punches and circular top knives. The creation of primary bone flaps—as in external craniotomies—is difficult.The piezoelectric osteotomes used in the present study allows creating a bone flap for endoscopic transnasal approaches in certain areas. The aim of this study was to prove the feasibility of piezoelectric endoscopic transnasal craniotomies. Study Design. Cadaveric study. Methods. On cadaveric specimens (N = 5), a piezoelectric system with specially designed hardware for endonasal application was applied and endoscopic transsphenoidal craniotomies at the sellar floor, tuberculum sellae, and planum sphenoidale were performed up to a size of 3–5?cm2. Results. Bone flaps could be created without fracturing with the piezoosteotome and could be reimplanted. Endoscopic handling was unproblematic and time required was not exceeding standard procedures. Conclusion. In a cadaveric model, the piezoelectric endoscopic transsphenoidal craniotomy (PETC) is technically feasible. This technique allows the surgeon to create a bone flap in endoscopic transnasal approaches similar to existing standard transcranial craniotomies. Future trials will focus on skull base reconstruction using this bone flap. PMID:24689037

Tomazic, Peter Valentin; Gellner, Verena; Koele, Wolfgang; Hammer, Georg Philipp; Braun, Eva Maria; Gerstenberger, Claus; Clarici, Georg; Holl, Etienne; Braun, Hannes; Stammberger, Heinz; Mokry, Michael

2014-01-01

461

Laser Scanning of a Monolithic Column during Processing in Middle Egypt  

NASA Astrophysics Data System (ADS)

From ancient quarries around Akoris in Middle Egypt, which belong to the Ptolemaic and Roman periods, the stone blocks could be carried to the working area located in the outside of the city. Those blocks included a giant monolithic column measured approximately 14m in length, which had been cracked for reasons unknown and must have contributed to disuse of monolith. The first deal is a comparison of plans drawn by the point clouds by laser scanning with those coming from plane-tabling, which had been one of popular methods for measuring in the last century. This part shows how the laser scanning technology is useful in far better measuring and documentation of the site. The second discuss is about a detailed assessment of the procedure of processing through the observation of chisel marks and the detail analysis about the 3 dimensional data. In the result, we are succeed to show the restoration of the procedure of the proceedings using guidelines and a wooden curve since we concentrate attention on the point of abstracting the centre line and shaving the surface into the round shape.

Ajioka, O.; Hori, Y.

2011-09-01

462

Measuring brain activity with magnetoresistive sensors integrated in micromachined probe needles  

NASA Astrophysics Data System (ADS)

An alternative neuroscience tool for magnetic field detection is described in this work, providing both micrometer-scale spatial resolution and high sensitivity to detect the extremely small magnetic fields (nT range) induced by the ionic currents flowing within electrically active neurons. The system combines an array of magnetoresistive sensors incorporated on micro-machined Si probes capable of being inserted within the brain current sources. The Si-etch based micromachining process for neural probes is demonstrated in the manufacture of a probe with 15 magnetoresistive sensors in the tip of each shaft. The probe shafts are formed by double-sided deep reactive ion etching on a double-side polished silicon wafer. The shafts typically have the dimensions 1.2 mm × 40 ?m × 300 ?m and end in chisel-shaped tips with an incorporated magnetoresistive sensor with dimensions of 30 ?m × 2 ?m. An accompanying interconnect flexible cable is glued and wirebonded enabling precise and flexible positioning of the probes in the neural tissue. Our analyses showed sharply defined probes and probe tips. The electrical and magnetic behavior of the sensors was verified, and a preliminary test with brain slices were performed.

Amaral, José; Gaspar, João; Pinto, Vitor; Costa, Tiago; Sousa, Nuno; Cardoso, Susana; Freitas, Paulo

2013-05-01

463

Comparative assessment of water infiltration of soils under different tillage systems in eastern Botswana  

NASA Astrophysics Data System (ADS)

Water infiltration is an important component of water balance for improving crop production potential in dryland soil tillage systems in Botswana, particularly in the eastern region. Hardsetting soils common in arable lands of Botswana, often require some kind of tillage such as mouldboard ploughing, chiselling and ripping to improve waterharvesting and crop growth conditions. The objective of this study was to compare ponded cumulative infiltration, steady state infiltration rate and sorptivity of soils cultivated using deep ripping, single and double mouldboard ploughing. This study was conducted on Chromic Luvisols (sandy loam), Haplic Luvisols (sandy clay loam), Ferric Luvisols (clay loam), and Ferric Arenosols (sand). Infiltration was measured using double ring infiltrometer method for 4 h. Although infiltration was smaller on traffic line of deep ripping system at all sites, it was only significantly ( P < 0.05) different on Ferric Luvisols and Ferric Arenosols. Compared with conventional ploughing, steady state infiltration was greater but not significantly ( P > 0.05) different under deep ripped. Cumulative and steady state infiltration rate was greater under sandy than loamy soils, smaller under double ploughing compared with single ploughed and deep ripped soils. Sorptivity was not significantly ( P > 0.05) different among tillage systems but was greater under sandy than sandy loam soils. Information on tillage and infiltration can improve implementation of waterharvesting technologies and crop production in Botswana.

Moroke, T. S.; Dikinya, O.; Patrick, C.

464

[Scanning electron microscopical observations on Pagumogonimus skrjabini metacercaria and juveniles].  

PubMed

The present paper reports on the results of scanning electron microscopical observations on seven excysted metacercariae and twelve juveniles of Pagumogonimus skrjabini. The former were from the naturally excysted metacercariae in fresh water in Ningquang District of Shaanxi Province and the latter were collected from the dogs and rats experimentally infected with metacercariae from the District mentioned above. Both excysted metacercariae and juveniles have tegumental ridges or folds on the surface of the body. The anterior two-thirds of the body surface are covered with many dome-shaped sensory papillae. There are rings of this kind of papillae on the rim of oral and ventral suckers. The papillae being obviously in decreasing number in the 30-40-day-old juveniles and adult worms. Except for the suckers and excretory pores, the whole body surface of the metacercariae and the juveniles are covered with posteriorly pointing tegumental spines which are relatively denser in the forebody than in the hindbody. Spines around the oral sucker are bayonet-shaped, and those on the rest part of the body surface are basically chisel-shaped. The authors considered it important that spines of P. skrjabini can be arranged singly or in groups. PMID:2065457

Zheng, S C; Zhang, M R

1991-01-01

465

The Sesquiterpene Biosynthesis and Vessel-Occlusion Formation in Stems of Aquilaria sinensis (Lour.) Gilg Trees Induced by Wounding Treatments without Variation of Microbial Communities  

PubMed Central

As widely recognized, agarwood formation in Aquilaria trees is induced by external wounding. Because agarwood usually harbors specific microbes, the function of microbes in agarwood formation has been debated for almost a century. In this study, two wounding methods, the burning-chisel-drilling method (BCD) and the whole-tree agarwood-inducing method (Agar-Wit), were used under the non-contamination of environmental microorganisms. After pyrosequencing the small rRNA subunits of the wounds induced by the BCD and Agar-Wit, no substantial variation was observed either in fungal and bacterial enrichment and diversity or in the relative abundances of taxa. By contrast, significant variations in fungal and bacterial communities were detected following the partial tree pruning (PTP)-wounding. The wound-induced sesquiterpene biosynthesis and vessel-occlusion formation, however, were found to be similar in all types of wounded trunks. We thus infer that wounding in the absence of variations in microbial communities may induce agarwood formation. This result does not support the long-standing notion that agarwood formation depends on microbes. PMID:25530613

Zhang, Zheng; Wei, Jianhe; Han, Xiaomin; Liang, Liang; Yang, Yun; Meng, Hui; Xu, Yanhong; Gao, Zhihui

2014-01-01

466

Electrical Bioimpedance-Controlled Surgical Instrumentation.  

PubMed

A bioimpedance-controlled concept for bone cement milling during revision total hip replacement is presented. Normally, the surgeon manually removes bone cement using a hammer and chisel. However, this procedure is relatively rough and unintended harm may occur to tissue at any time. The proposed bioimpedance-controlled surgical instrumentation improves this process because, for example, most risks associated with bone cement removal are avoided. The electrical bioimpedance measurements enable online process-control by using the milling head as both a cutting tool and measurement electrode at the same time. Furthermore, a novel integrated surgical milling tool is introduced, which allows acquisition of electrical bioimpedance data for online control; these data are used as a process variable. Process identification is based on finite element method simulation and on experimental studies with a rapid control prototyping system. The control loop design includes the identified process model, the characterization of noise as being normally distributed and the filtering, which is necessary for sufficient accuracy ( ±0.5 mm). Also, in a comparative study, noise suppression is investigated in silico with a moving average filter and a Kalman filter. Finally, performance analysis shows that the bioimpedance-controlled surgical instrumentation may also performs effectively at a higher feed rate (e.g., 5 mm/s). PMID:25423656

Brendle, Christian; Rein, Benjamin; Niesche, Annegret; Korff, Alexander; Radermacher, Klaus; Misgeld, Berno; Leonhardt, Steffen

2014-11-21

467

A hybrid polymer-glass achromatic microlens array fabricated by compression molding  

NASA Astrophysics Data System (ADS)

This paper presents the feasibility of creating a hybrid polymer-glass achromatic microlens array by compression molding. This affordable and high precision microlens array design has potential applications in the optical industry for its capability of correcting chromatic aberration. In this research a doublet design was investigated. Specifically, polycarbonate and P-SK57 glass were selected as the equivalents of flint and crown glass for their opposite dispersion properties. Ultraprecision diamond machining was utilized to manufacture the mold with an asymmetric pattern. The optical quality in the mold surface was obtained without post-machining-polishing. Both the glass and polymer microlens arrays were fabricated by thermal compression molding at different forming temperatures. After the glass microlens array was molded, it was used as the top mold half for polymer compression molding. Two chisel-shaped cavities were fabricated simultaneously when the glass lens array mold was machined. These two cavities were used as fiducial marks for assembling the P-SK57 glass part and the polycarbonate part during the second molding action. The single uninterrupted operation was developed in this study to create both optical surfaces and the fiducial marks such that high assembly tolerance could be achieved. Furthermore, numerical simulation for compression molding was conducted to study the geometry profile error of the microlens. Finally, the geometry and optical measurements were performed to demonstrate the effectiveness of the hybrid polymer-glass achromatic microlens array.

Li, Likai; He, Peng; Wang, Fei; Georgiadis, Kyriakos; Dambon, Olaf; Klocke, Fritz; Yi, Allen Y.

2011-05-01

468

Biderbost Basketry  

NSDL National Science Digital Library

The archeological site known as the Biderbost site was discovered in 1959 "after the Snoqualmie flooded, and revealed many basketry fragments, fishhooks, net weights, projectile points, adzes, chisels, choppers, scrapers, and knives. " This collection of basketry now resides at the University of Washington's Burke Museum in Seattle, and the excellent online site devoted to the collection examines "basketry objects more closely by looking at their origins on the Snoqualmie River, their excavation, weaving techniques, and the newest chapter in their lives as part of the archaeology collections at the Burke Museum." Visitors should begin by clicking on the Archaeology link at the top of the page; here they can learn more about the site and check out a short video where Dr. David Rice discusses the Biderbost Site. Visitors interested in the materials used for the baskets (which included spruce root, cherry bark and cedar) and the weaving techniques will find The "Basketry Technology" tab to be informative. Another short video can be found here, which provides the helpful explanations of a basketry expert to explain the process of analyzing the history of the basket, such as its uses and its quality.

469

Earliest floral grave lining from 13,700-11,700-y-old Natufian burials at Raqefet Cave, Mt. Carmel, Israel.  

PubMed

Flowering plants possess mechanisms that stimulate positive emotional and social responses in humans. It is difficult to establish when people started to use flowers in public and ceremonial events because of the scarcity of relevant evidence in the archaeological record. We report on uniquely preserved 13,700-11,700-y-old grave linings made of flowers, suggesting that such use began much earlier than previously thought. The only potentially older instance is the questionable use of flowers in the Shanidar IV Neanderthal grave. The earliest cemeteries (ca. 15,000-11,500 y ago) in the Levant are known from Natufian sites in northern Israel, where dozens of burials reflect a wide range of inhumation practices. The newly discovered flower linings were found in four Natufian graves at the burial site of Raqefet Cave, Mt. Carmel, Israel. Large identified plant impressions in the graves include stems of sage and other Lamiaceae (Labiatae; mint family) or Scrophulariaceae (figwort family) species; accompanied by a plethora of phytoliths, they provide the earliest direct evidence now known for such preparation and decoration of graves. Some of the plant species attest to spring burials with a strong emphasis on colorful and aromatic flowers. Cave floor chiseling to accommodate the desired grave location and depth is also evident at the site. Thus, grave preparation was a sophisticated planned process, embedded with social and spiritual meanings reflecting a complex preagricultural society undergoing profound changes at the end of the Pleistocene. PMID:23818584

Nadel, Dani; Danin, Avinoam; Power, Robert C; Rosen, Arlene M; Bocquentin, Fanny; Tsatskin, Alexander; Rosenberg, Danny; Yeshurun, Reuven; Weissbrod, Lior; Rebollo, Noemi R; Barzilai, Omry; Boaretto, Elisabetta

2013-07-16

470

Intraocular Metallic Foreign Body: Role of Computed Tomography  

PubMed Central

Orbital foreign bodies remain a serious diagnostic problem, despite development of diagnostic imaging techniques. Non-metallic orbital foreign body will not be detected in routine x-ray. Here we are presenting a case of 32-year-old male presented with acute pain in left eye immediately after he had been pounding a metal object with a metal chisel. Following this event patient develop blurring of vision in left eye with tearing. Patient’s vision in left eye was found to be hand motion with conjunctiva mildly injected, left corneal central 1 mm Seidel-negative full-thickness laceration and dense traumatic cataract was seen on ocular examination. Dilated fundus examination of left eye was not possible due to traumatic cataract. Vitreous hemorrhage, vitreous detachment and a echogenic foreign body present in posterior segment in B–Scan sonography. Well-defied hyperdense foreign body producing streak artifacts with vitreous hemorrhage was seen in the posterior chamber of left eyeball in CT orbit. The patient was diagnosed with a corneal laceration, traumatic cataract, vitreous hemorrhage and a metallic intraocular foreign body. He was brought to the operating room urgently for corneal laceration repair, pars plana vitrectomy, lensectomy, and removal of the metallic intraocular foreign body done. PMID:25654008

Jigar J., Patel; Mehta, Chetan; Narottam A., Patel

2014-01-01

471

Endoscopic dacryocystorhinostomy.  

PubMed

Dacryocystorhinostomy (DCR) is the treatment of distal nasolacrimal duct blockage. It has got many advantages of over external DCR with higher patient's acceptance. Twenty one consecutive cases of endoscopic DCR were studied during the period of two and a half years with a mean follow up period of 13.12 months (SD=7.05). The mean age of cases was 42.95 years (SD=14.49). In most of the cases the cause was either idiopathic (71.43%) or inflammatory (23.81%). The techniques used for making bony window were chisel-hammer (19.50%), powered drill (23.81%), Kerrison punch forceps (14.29%) or combination of powered drill and Kerrison punch forceps (42.86%). Silicon stent was used in 71.43% cases. There was no significant peroperative complication; premature extrusion of stent (4.76%), synaechia (9.52%), excessive granulation tissue formation (9.52%) and stomal stenosis with recurrence of symptoms (9.52%) were the complications noticed here. Anatomical success with patent stoma was observed in 90.48% cases but symptomatic improvement with dry comfortable eyes were seen in 86% cases. There was no statistically significant difference of outcome between this study and that of recently published studies (p>0.05). Some comparative studies showed both higher and lower success rates of endoscopic DCR than external procedure but there was no significant difference (p>0.05). PMID:21240159

Rahman, S H; Tarafder, K H; Ahmed, M S; Saha, K L; Tariq, A

2011-01-01

472

Chewing through the Miocene: an examination of the feeding musculature in the ground sloth Hapalops from South America (Mammalia: Pilosa)  

PubMed Central

Hapalops, a smaller-sized and early sloth of the Megatheroidea, appeared in the middle Miocene Santa Cruz formation of Argentina. This genus is part of the group from which later, larger megatheroids arose, i.e., Nothrotheriops and Megatherium. Many cranial characters support this idea; however Hapalops is not merely a smaller antecedent of the later forms. Specifically, Hapalops retains short anterior caniniform teeth, and a temporomandibular joint elevated above the cheek tooth row; a combination distinct among sloths. An elevated temporomandibular joint occurs in Bradypus, a tree sloth with anterior chisel-shaped teeth instead of caniniforms, and the tree sloth Choloepus, which is aligned with the megalonychids, has anterior caniniforms. Hapalops has an elongated zygomatic ascending process that is reminiscent of that in Bradypus; however, the Bradypus skull is extremely foreshortened while that of Hapalops is elongated, as in nothrotheres, but not deepened as in megatheres. Previous work identified many sloth cranial character complexes, and functional limitations on skull feature combinations. The unique Hapalops character patterns indicate a selective feeder with a mediolaterally oriented grinding stroke during mastication. PMID:25075299

Naples, Virginia L.; McAfee, Robert K.

2014-01-01

473

Chewing through the Miocene: an examination of the feeding musculature in the ground sloth Hapalops from South America (Mammalia: Pilosa).  

PubMed

Hapalops, a smaller-sized and early sloth of the Megatheroidea, appeared in the middle Miocene Santa Cruz formation of Argentina. This genus is part of the group from which later, larger megatheroids arose, i.e., Nothrotheriops and Megatherium. Many cranial characters support this idea; however Hapalops is not merely a smaller antecedent of the later forms. Specifically, Hapalops retains short anterior caniniform teeth, and a temporomandibular joint elevated above the cheek tooth row; a combination distinct among sloths. An elevated temporomandibular joint occurs in Bradypus, a tree sloth with anterior chisel-shaped teeth instead of caniniforms, and the tree sloth Choloepus, which is aligned with the megalonychids, has anterior caniniforms. Hapalops has an elongated zygomatic ascending process that is reminiscent of that in Bradypus; however, the Bradypus skull is extremely foreshortened while that of Hapalops is elongated, as in nothrotheres, but not deepened as in megatheres. Previous work identified many sloth cranial character complexes, and functional limitations on skull feature combinations. The unique Hapalops character patterns indicate a selective feeder with a mediolaterally oriented grinding stroke during mastication. PMID:25075299

Naples, Virginia L; McAfee, Robert K

2014-01-01

474

Skirted projectiles for railguns  

DOEpatents

A single skirt projectile (20) having an insulating skirt (22) at its rear, or a dual trailing skirt projectile (30, 40, 50, 60) having an insulating skirt (32, 42, 52, 62) succeeded by an arc extinguishing skirt (34, 44, 54, 64), is accelerated by a railgun accelerator 10 having a pair of parallel conducting rails (1a, 1b) which are separated by insulating wall spacers (11). The insulating skirt (22, 32, 42, 52, 62) includes a plasma channel (38). The arc extinguishing skirt (34, 44, 54, 64) interrupts the conduction that occurs in the insulating skirt channel (38) by blocking the plasma arc (3) from conducting current from rail to rail (1a, 1b) at the rear of the projectile (30, 40, 50, 60). The arc extinguishing skirt may be comprised of two plates (36a, 36b) which form a horseshoe wherein the plates are parallel to the rails (1a, b); a chisel-shape design; cross-shaped, or it may be a cylindrical (64). The length of the insulating skirt channel is selected such that there is sufficient plasma in the channel to enable adequate current conduction between the rails (1a, 1b).

Hawke, Ronald S. (Livermore, CA); Susoeff, Allan R. (Pleasanton, CA)

1994-01-01

475

Skirted projectiles for railguns  

DOEpatents

A single skirt projectile (20) having an insulating skirt (22) at its rear, or a dual trailing skirt projectile (30, 40, 50, 60) having an insulating skirt (32, 42, 52, 62) succeeded by an arc extinguishing skirt (34, 44, 54, 64), is accelerated by a railgun accelerator 10 having a pair of parallel conducting rails (1a, 1b) which are separated by insulating wall spacers (11). The insulating skirt (22, 32, 42, 52, 62) includes a plasma channel (38). The arc extinguishing skirt (34, 44, 54, 64) interrupts the conduction that occurs in the insulating skirt channel (38) by blocking the plasma arc (3) from conducting current from rail to rail (1a, 1b) at the rear of the projectile (30, 40, 50, 60). The arc extinguishing skirt may be comprised of two plates (36a, 36b) which form a horseshoe wherein the plates are parallel to the rails (1a, b); a chisel-shape design; cross-shaped, or it may be a cylindrical (64). The length of the insulating skirt channel is selected such that there is sufficient plasma in the channel to enable adequate current conduction between the rails (1a, 1b).

Hawke, R.S.; Susoeff, A.R.

1994-01-04

476

The surgical closure of exposed skull.  

PubMed

The closure of scalp defects is still surrounded by many uncertainties. Free skin graft has proved most successful. Thiersch graft, split skin graft and full thickness skin graft have their indication for use. Thiersch skin graft is used as a temporary dressing, in order to achieve aseptic wound conditions, but cannot be looked upon as a lasting solution cosmetically and functionally. Split skin is used only for the closure of smaller defects. Full thickness skin grafts are most suitable, because they offer a lasting coverage, which meets to all demands. If the outer table of the skull is exposed, multiple bur holes could be placed immediately in cases of fresh injuries, and these facilitate the growth of granulation tissues which nourish the outer table adequately, so that it remains viable. Exposure of the outer table of the skull for a long time leads to necrosis of the superficial layer. It must therefore be removed down to the diploe with a chisel, or brought to early sequestration by means of numerous perforations made with a bur. Skin should not, however, be placed on the exposed diploe immediately, but it should be allowed to granulate, so as to produce a layer of fibrous tissue beneath the grafted full thickness skin. Thus a direct adhesion to the bony underlayer is prevented, and the skin remains movable. The danger of pressure ulcer is also prevented. The figures show the surgical procedure. PMID:1100743

Widmaier, W

1975-09-01

477

The Panoti and some other fantastic forms of macrotia.  

PubMed

"He had the form of a human being... His ears were as long as clusters of dates or elephant ears, and they covered his shoulders" ("The thousand and one nights", Sinbad the sailor, 546th night, circa IXth century AD). "About his ears, I shall tell you all the truth: They have the capacity of about 300 liters. When he is surprised by wind or tempest, He can immediately cover his head. He does not frighten the water at all, Even if it rained enormously during one full month. The other ear, he uses as a shield. It is hanging in front of his face up to his baldric. Thanks to his ears, he does not fear any feathered arrow, steel lame, or chiselled spear" (The ears of Isabras in "La Bataille Loquifer", or "Geste de Rainouard", from the "Geste de Guillaume d'Orange", XIIIth cent. "In that neighbouring isle, I heard someone saying that there were men whose ears were so big that they were able to cover their arms with them. That people are the Caphri". PMID:16910292

Tainmont, J

2006-01-01

478

The Sesquiterpene Biosynthesis and Vessel-Occlusion Formation in Stems of Aquilaria sinensis (Lour.) Gilg Trees Induced by Wounding Treatments without Variation of Microbial Communities.  

PubMed

As widely recognized, agarwood formation in Aquilaria trees is induced by external wounding. Because agarwood usually harbors specific microbes, the function of microbes in agarwood formation has been debated for almost a century. In this study, two wounding methods, the burning-chisel-drilling method (BCD) and the whole-tree agarwood-inducing method (Agar-Wit), were used under the non-contamination of environmental microorganisms. After pyrosequencing the small rRNA subunits of the wounds induced by the BCD and Agar-Wit, no substantial variation was observed either in fungal and bacterial enrichment and diversity or in the relative abundances of taxa. By contrast, significant variations in fungal and bacterial communities were detected following the partial tree pruning (PTP)-wounding. The wound-induced sesquiterpene biosynthesis and vessel-occlusion formation, however, were found to be similar in all types of wounded trunks. We thus infer that wounding in the absence of variations in microbial communities may induce agarwood formation. This result does not support the long-standing notion that agarwood formation depends on microbes. PMID:25530613

Zhang, Zheng; Wei, Jianhe; Han, Xiaomin; Liang, Liang; Yang, Yun; Meng, Hui; Xu, Yanhong; Gao, Zhihui

2014-01-01

479

Use of scleractinian corals to indicate marine pollution in the northern Gulf of Aqaba, Jordan.  

PubMed

The actual and fatal concentrations of selected heavy metals, including cadmium, cobalt, copper, lead, nickel, and zinc in corals from the Gulf of Aqaba were determined. Several living coral samples of different species (e.g., Porites) were collected from shallow depths (of about 5 m) at a number of sites along the Jordanian Gulf of Aqaba coast. The coral samples were collected using either a pneumatic diamond drill corer (for Porites) or a hammer and chisel (for other branched species). Some of the corals that had been collected were analyzed for heavy metals using atomic absorption spectrometry, and other samples were used in incubation experiments. The heavy metal concentrations were determined separately in the coral skeleton and the tissue layer. Heavy metal concentrations have not previously been determined in corals from the Gulf of Aqaba. We conclude that corals are suitable for use as proxy tools for assessing environmental pollution (i.e., they are bioindicators) in the Gulf of Aqaba and the Red Sea. Therefore, this study provides useful information on the degree of heavy metal contamination in the study area. PMID:25637389

Barakat, S A; Al-Rousan, S; Al-Trabeen, M S

2015-02-01

480

A response surface model predicting the in vivo insertion behavior of micromachined neural implants  

NASA Astrophysics Data System (ADS)

The mechanical damage caused by the insertion of a foreign body into living tissue is inevitable, especially when a considerable stiffness mismatch is present, as in the case of micromachined neural implants and brain tissue. However, the response surface model based on a central composite experimental design described in this study showed that for particular configurations of the implant tip angle, width, thickness or insertion speed, some of these factors could be safely increased without causing an unwanted significant force or tissue dimpling increase. The model covers chisel tip angles between 10° and 50°, implant widths within the 200-400 µm range and thicknesses between 50 and 150 µm. The insertion speed has been varied from 10 up to 100 µm s-1 to reach a final insertion depth of 6 mm. Coating the implant with parylene C proved to be beneficial in reducing the friction between the implant and the surrounding tissue. Successfully validated for a particular implant geometry, this model could be used as an insertion behavior prediction tool for the design optimization of future neural implants.

Andrei, A.; Welkenhuysen, M.; Nuttin, B.; Eberle, W.

2012-02-01

481

Changes in the organic matter forms in chernozems of the Kamennaya Steppe under different land uses, locations, and hydromorphism degrees  

NASA Astrophysics Data System (ADS)

The soils of the Kamennaya Steppe (Voronezh oblast) were studied. The rate of changes in the contents of Corg and the particular forms of organic matter (labile, microbial, and stable) were revealed in the quasi-natural soils of the fallows and shelterbelt and in the arable soils (rainfed farming for 12, 55, 85, and 115 yrs and irrigated farming for 40 yrs) of different positions on the watersheds and slopes. The effect of the increased soil moistening in the recent decades was also studied. In the upper 50 cm of the fallow soils that were not plowed since 1882, the relative Corg accumulation in the recent 30 yrs has amounted to 5%. The soils of the shelterbelt planted in 1903 were similar to the fallow soils. As compared to the soil of the unmown fallow, the Corg loss from the 1-m soil layer under the shelterbelt and the 12-year-old cropland were less than 9%; the losses from the plowed soils (used for 55-115 yrs) were 21-27% on the watersheds and 37-46% on the slopes. In the first decade, the rate of the Corg losses in the 0- to 20-cm layer of the cultivated chernozem was 120 g C/m2. With the increasing duration of the soil plowing (from 55 to 115 yrs), the Corg losses decreased from 45 to 28 g C/m2 per yr in the watershed soils and from 51 to 35 g C/m2 per yr in the soils on the slopes. The maximum loss of Corg was found for the soils on slopes, waterlogged soils, and irrigated soils. In the slope soils, the Corg loss due to erosion was 9-18% of the total. In the upper horizons of the old agrogenic soils, compared to the soil of the unmown fallow, the Cha/Cfa increased, since the content of fulvic acids (FA) faster decreased than that of the humic acids (HA); the C content of the nonhydrolyzable residue was reduced. The slope and waterlogged soils differed from the watershed soils in the smaller amounts of HA and FA and in the greater content of humin carbon. In the 0- to 20-cm layer of the soils studied, the rate of the basal respiration (BR) was 0.2-0.5 ?g C/g soil per h, the content of the microbial biomass (Cmicr) was 326-1073 ?g C/g, and the share of Cmicr amounted to 1.0-1.9%. These values were minimal in the irrigated soil and maximal in the fallow ones. A high correlation coefficient ( r = 0.88-0.92) was found between the Cmicr content and the BR, between the contents of Corg and HA, and between the contents of Corg and mobile C. The correlation coefficient between the contents of Corg and FA and Corg and humin C was 0.67.

Prikhod'ko, V. E.; Cheverdin, Yu. I.; Titova, T. V.

2013-12-01

482

Eight years of Conservation Agriculture-based cropping systems research in Eastern Africa to conserve soil and water and mitigate effects of climate change  

NASA Astrophysics Data System (ADS)

In Ethiopia, repeated plowing, complete removal of crop residues at harvest, aftermath grazing of crop fields and occurrence of repeated droughts have reduced the biomass return to the soil and aggravated cropland degradation. Conservation Agriculture (CA)-based resource conserving cropping systems may reduce runoff and soil erosion, and improve soil quality, thereby increasing crop productivity. Thus, a long-term tillage experiment has been carried out (2005 to 2012) on a Vertisol to quantify - among others - changes in runoff and soil loss for two local tillage practices, modified to integrate CA principles in semi-arid northern Ethiopia. The experimental layout was a randomized complete block design with three replications on permanent plots of 5 m by 19 m. The tillage treatments were (i) derdero+ (DER+) with a furrow and permanent raised bed planting system, ploughed only once at planting by refreshing the furrow from 2005 to 2012 and 30% standing crop residue retention, (ii) terwah+ (TER+) with furrows made at 1.5 m interval, plowed once at planting, 30% standing crop residue retention and fresh broad beds, and (iii) conventional tillage (CT) with a minimum of three plain tillage operations and complete removal of crop residues. All the plowing and reshaping of the furrows was done using the local ard plough mahresha and wheat, teff, barley and grass pea were grown. Glyphosate was sprayed starting from the third year onwards (2007) at 2 l ha-1 before planting to control pre-emergent weeds in CA plots. Runoff and soil loss were measured daily. Soil water content was monitored every 6 days. Significantly different (p<0.05) runoff coefficients averaged over 8 years were 14, 20 and 27% for DER+, TER+ and CT, respectively. Mean soil losses were 4 t ha-1 y-1 in DER+, 13 in TER+ and 18 in CT. Soil water storage during the growing season was constantly higher in CA-based systems compared with CT. A period of at least three years of cropping was required before improvements in crop yield became significant. Further, modeling of the sediment budgets shows that total soil loss due to sheet and rill erosion in cropland, when CA would be practiced at large scale in a 180 ha catchment, would reduce to 581 t y-1, instead of 1109 t y-1 under the current farmer practice. Using NASA/GISS Model II precipitation projections of IPCC scenario A1FI, CA is estimated to reduce soil loss and runoff and mitigate the effect of increased rainfall due to climate change. For smallholder farmers in semi-arid agro-ecosystems, CA-based systems constitute a field rainwater and soil conservation improvement strategy that enhances crop and economic productivity and reduces siltation of reservoirs, especially under changing climate. The reduction in draught power requirement would enable a reduction in oxen density and crop residue demand for livestock feed, which would encourage smallholder farmers to increase biomass return to the soil. Adoption of CA-based systems in the study area requires further work to improve smallholder farmers' awareness on benefits, to guarantee high standards during implementation and to design appropriate weed management strategies.

Araya, Tesfay; Nyssen, Jan; Govaerts, Bram; Lanckriet, Sil; Baudron, Frédéric; Deckers, Jozef; Cornelis, Wim

2014-05-01

483

GPR study of a prehistoric archaeological site near Point Barrow, Alaska  

NASA Astrophysics Data System (ADS)

A ground penetrating radar (GPR) study was performed on the prehistoric Thule cemetery site near Point Barrow, Alaska. The goals of this study were (a) to test this technology in this type of polar environment, and (b) to search for burials and other archaeological features in a location in imminent danger from ocean erosion. The Nuvuk site is currently eroding at an average rate measured at over 6 m/year. Prior archaeological work at the site had recovered over 80 burials with nearly 100 individuals represented, all of which were less than 1 m below surface, and detectable with small test pits. In addition, the first coastal Ipiutak occupation known north of Point Hope had been recently discovered, at a depth of nearly 2m below surface, in the erosion face. The occupation appeared to have been terminated by a large storm which overwashed the site, leaving a strandline immediately superimposed on the living surface. After that, approximately 1.5 m of sterile gravels had been deposited before the surface on which the Thule people were living formed. Both occupations are of considerable scientific interest. The matrix at the site consists of unconsolidated beach gravels, which necessitates opening large surface areas or use of shoring to test even small units to the depths of the Ipiutak deposit (approximately 8m x 8m at the surface to test 1m x 1m at 2m depth). Such excavations promote erosion, and are very costly in terms of time and labor, so a means to detect features buried at depths greater than those exposed by shovel test pits was desirable. GPR seemed a likely candidate, but it had not been used in such conditions before, and thus it was necessary to test it thoroughly prior to relying on GPR to eliminate areas from physical testing. The GPR imaged the subsurface to a depth of 3 meters at a frequency of 500MHz. Meter-deep test pits were placed at 2-meter intervals in the survey area in a grid pattern since the efficacy of the technology had yet to be shown. The results of the test pits and the GPR were in agreement. It was anticipated that there might be few or no remaining burials in this location since the number of burials had been declining with distance from the center of the larger site. Thus it was surprising when the GPR detected an anomaly that turned out to be the deepest burial in the whole site. In fact, it was so deeply buried that the standard shovel test pitting method might not have detected it. It proved to be a very well-preserved individual, with fairly intact garments. In addition to the burial site, the GPR was used to image a number of "strandlines" as well as other deep (>1m) features in this area. These correspond in depth and orientation to two partial Ipiutak features which have been exposed and recorded in the erosion face in two separate field seasons. It was not possible to test to that depth, but subsequent coastal erosion has exposed additional strandline debris at the depth and location predicted by the GPR data. Two- and three-dimensional images of these features will be presented, along with a detailed technical description of the GPR methods used in this environment.

Herman, R. B.; Jensen, A. M.

2012-12-01

484