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Articles 11191 - 11220 of 12002

Full-Text Articles in Physical Sciences and Mathematics

On Preconditioning Schur Complement And Schur Complement Preconditioning, Jun Zhang Jan 2000

On Preconditioning Schur Complement And Schur Complement Preconditioning, Jun Zhang

Computer Science Faculty Publications

We study two implementation strategies to utilize Schur complement technique in multilevel recursive incomplete LU preconditioning techniques (RILUM) for solving general sparse matrices. The first strategy constructs a RILUM to precondition the original matrix. The second strategy solves the first Schur complement matrix using the lower level parts of the RILUM as the preconditioner. We discuss computational and memory costs of both strategies and the potential effect on grid independent convergence rate of RILUM with different implementation strategies.


Effects Of Longwall Mining On Hydrology, Leslie County, Kentucky Part 2: During-Mining Conditions, Shelley Minns Hutcheson, James A. Kipp, James S. Dinger, Lyle V.A. Sendlein, Daniel I. Carey, Gregory L. Secrist Jan 2000

Effects Of Longwall Mining On Hydrology, Leslie County, Kentucky Part 2: During-Mining Conditions, Shelley Minns Hutcheson, James A. Kipp, James S. Dinger, Lyle V.A. Sendlein, Daniel I. Carey, Gregory L. Secrist

Report of Investigations--KGS

The effects of longwall coal mining on hydrology in the Eastern Kentucky Coal Field are being investigated. The study area is in the Edd Fork watershed in southern Leslie County, over Shamrock Coal Company's Beech Fork Mine. Longwall panels approximately 700 ft wide are separated by three-entry gateways that are approximately 200 ft wide. The mine is operated in the Fire Clay (Hazard No. 4) coal; overburden thickness ranges from 300 to 800 ft. Mining began in panel 1 in September 1991 and concluded with panel 8 in September 1994. Long-term monitoring consisting of a network of piezometers and time-domain …


Effects Of Longwall Mining On Hydrogeology, Leslie County, Kentucky Part 3: Post-Mining Conditions, Shelley Minns Hutcheson, James A. Kipp, James S. Dinger, Daniel I. Carey, Lyle V.A. Sendlein, Gregory L. Secrist Jan 2000

Effects Of Longwall Mining On Hydrogeology, Leslie County, Kentucky Part 3: Post-Mining Conditions, Shelley Minns Hutcheson, James A. Kipp, James S. Dinger, Daniel I. Carey, Lyle V.A. Sendlein, Gregory L. Secrist

Report of Investigations--KGS

The effects of longwall coal mining on hydrology in the Eastern Kentucky Coal Field have been investigated since 1991. The study area is in the Edd Fork watershed in southern Leslie County, over Shamrock Coal Company's Beech Fork Mine. Longwall panels approximately 700 ft wide are separated by three-entry gateways that are approximately 200 ft wide. The mine is operated in the Fire Clay (Hazard No. 4) coal; overburden thickness ranges from 300 to 800 ft. Mining began in panel 1 in September 1991 and concluded with panel 8 in September 1994. Long-term monitoring consisting of a network of piezometers …


The Effect Of Turfgrass Maintenance On Surface-Water Quality In A Suburban Watershed, Inner Blue Grass, Kentucky, R. Michael Williams, James S. Dinger, Andrew J. Powell, Dwayne R. Edwards Jan 2000

The Effect Of Turfgrass Maintenance On Surface-Water Quality In A Suburban Watershed, Inner Blue Grass, Kentucky, R. Michael Williams, James S. Dinger, Andrew J. Powell, Dwayne R. Edwards

Report of Investigations--KGS

Nutrients and pesticides applied during routine maintenance or establishment of turfgrass could result in nonpoint-source pollution. Nutrient and pesticide concentrations in water exiting a turfgrass management area in the Sinking Creek watershed, a suburban watershed in the Inner Blue Grass Region of central Kentucky, were monitored. This watershed was selected because it contains multiple land uses: agricultural, residential, and recreational (golf course).

A survey was conducted to determine the extent to which lawn-care products are used in the residential sector of the watershed. For the golf-course portion, the golf-course superintendent recorded chemical application daily.

Runoff from the golf course was …


Generalized Geologic Bedrock Conditions As Related To Solid-Waste Landfills In Kentucky, Martin C. Noger Jan 2000

Generalized Geologic Bedrock Conditions As Related To Solid-Waste Landfills In Kentucky, Martin C. Noger

Map and Chart--KGS

This map is not intended to be used for selecting individual landfill sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions throughout the state that affect the selection of solid-waste disposal sites.


Coal Resources Of The Springfield Coal Bed In Western Kentucky, William M. Andrews Jr., Robert E. Andrews, John K. Hiett Jan 2000

Coal Resources Of The Springfield Coal Bed In Western Kentucky, William M. Andrews Jr., Robert E. Andrews, John K. Hiett

Map and Chart--KGS

Historically, the Springfield (Western Kentucky No. 9) coal bed has been the leading source of production in the Western Kentucky Coal Field. The Springfield coal is known for its lateral continuity in terms of both thickness and coal quality. It is estimated to have the largest original and remaining resource in the Western Kentucky Coal Field (Greb and others, 1992).


Quality Characteristics Of The Springfield Coal In Western Kentucky, Cortland F. Eble Jan 2000

Quality Characteristics Of The Springfield Coal In Western Kentucky, Cortland F. Eble

Map and Chart--KGS

Thickness and quality data from the Kentucky Coal Resources Information System (KCRIS) for the Springfield coal bed are summarized in this chart. Parameter averages and range of values are presented in the two tables, and average values are displayed graphically by county.


Geologic Map Of Kentucky, Garland R. Dever Jr., M. C. Noger Jan 2000

Geologic Map Of Kentucky, Garland R. Dever Jr., M. C. Noger

Map and Chart--KGS

This map shows the geologic age of rocks and sediments at the surface in Kentucky. Sedimentary rocks, deposited from about 465 to 290 million years ago during the Ordovician, Silurian, Devonian, Mississippian, and Pennsylvanian Periods, crop out across the state. The rocks mainly consist of shale, limestone, sandstone, and siltstone. As shown in the cross sections, these surface rocks are underlain by older unexposed rocks of Precambrian, Cambrian, and Ordovician age.

Small bodies of igneous rocks were intruded into the state's bedrock about 270 million years ago during the Permian Period. They crop out in Elliott County of northeastern Kentucky, …


Magnetic Confinement, Magnetohydrodynamic Waves And Smooth Line Profiles In Active Galactic Nuclei, M. C. Bottorff, Gary J. Ferland Jan 2000

Magnetic Confinement, Magnetohydrodynamic Waves And Smooth Line Profiles In Active Galactic Nuclei, M. C. Bottorff, Gary J. Ferland

Physics and Astronomy Faculty Publications

In this paper, we show that if the broad-line region clouds are in approximate energy equipartition between the magnetic field and gravity, as hypothesized by Rees, there will be a significant effect on the shape and smoothness of broad emission-line profiles in active galactic nuclei. Linewidths of contributing clouds or flow elements are much wider than their thermal widths, because of the presence of non-dissipative magnetohydrodynamic waves and their collective contribution produce emission-line profiles broader and smoother than would be expected if a magnetic field were not present. As an illustration, a simple model of isotropically emitting clouds, normally distributed …


1998-1999 Monitoring Strategy, Kentucky River Basin Management Unit, L. Ormsbee, G. Epp, E. Caudill, Lee Colten Jan 2000

1998-1999 Monitoring Strategy, Kentucky River Basin Management Unit, L. Ormsbee, G. Epp, E. Caudill, Lee Colten

KWRRI Research Reports

During the fall of 1997 and spring of 1998 about 40 individuals and more than 30 organizations and agencies provided input into the development of a monitoring strategy for the Kentucky River basin under the Kentucky Watershed Management Framework. In addition to the agencies that were able to commit resources to the monitoring effort, citizen input was sought in the design of the strategy. Citizen monitoring efforts are also providing valuable information in many portions of the state. The intent of the coordinated planning process was to carefully consider agency resources and capabilities, taking into account where and when each …


Kentucky Water Resources Research Institute Annual Technical Report Fy 1999, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2000

Kentucky Water Resources Research Institute Annual Technical Report Fy 1999, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The FY 1999 Annual Technical Report for Kentucky consolidates the reporting requirements of the Section 104(b) base grant and regional competitive grant awards in a single technical report which includes: 1) a synopsis of each ongoing research project and each research project completed during the period, 2) a list of related reports published, 3) a brief description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable achievements and awards during the year. The activities supported by Section 104 (b) and the required matching funds are interwoven into the Kentucky Water Resources ResearchInsitute's …


Mining Geology Of The Lower Elkhorn Coal, Stephen F. Greb, Gerald A. Weisenfluh Jan 2000

Mining Geology Of The Lower Elkhorn Coal, Stephen F. Greb, Gerald A. Weisenfluh

Map and Chart--KGS

The Lower Elkhorn (and its equivalents) is one of the leading producers of coal in the Eastern Kentucky Coal Field with 12 to 18 million short tons of annual production between 1974 and 1996, according to the Kentucky Department of Mines and Minerals. Stratigraphically, the coal occurs in the lower part of the Pikeville Formation of the Breathitt Group (Fig. 1), which was previously part of the Breathitt Formation (Chesnut, 1992). The coal occurs from 150 to 300 ft above the base of a thick coarsening-upward sequence containing the Betsie Shale and from 250 to 450 ft beneath the base …


Quality Characteristics Of The Lower Elkhorn Coal Bed In Eastern Kentucky, Cortland F. Eble Jan 2000

Quality Characteristics Of The Lower Elkhorn Coal Bed In Eastern Kentucky, Cortland F. Eble

Map and Chart--KGS

Thickness and quality data from the Kentucky Coal Resources Information System (KCRIS) are summarized in this chart for the Lower Elkhorn coal bed (and equivalents). Parameter averages and ranges of values are presented in the two tables, and average values are displayed graphically by county.


Total Coal Thickness Of The Fire Clay And Fire Clay Rider Coals In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, Stephen F. Greb, Jeffery A. Esterle Jan 2000

Total Coal Thickness Of The Fire Clay And Fire Clay Rider Coals In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, Stephen F. Greb, Jeffery A. Esterle

Map and Chart--KGS

This map is one of a series that shows the regional characteristics of the Fire Clay coal zone. The maps were prepared as part of the U.S. Geological Survey's National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. Within the zone, the Fire Clay coal is the most economically important bed and is one of the leading producers in the state of Kentucky. It is known for a persistent flint-clay parting that is believed to be of volcanic origin. This map represents the total coal …


Coal Resources Of The Upper Elkhorn No. 3a Coal (Lower Bed) In Eastern Kentucky, Jeffery A. Esterle, Ernest E. Thacker, Gerald A. Weisenfluh, John K. Hiett Jan 2000

Coal Resources Of The Upper Elkhorn No. 3a Coal (Lower Bed) In Eastern Kentucky, Jeffery A. Esterle, Ernest E. Thacker, Gerald A. Weisenfluh, John K. Hiett

Map and Chart--KGS

This map is one of a series that shows the regional characteristics of the Upper Elkhorn No. 3 coal zone. The maps were prepared as part of the U.S. Geological Survey's National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. The Upper Elkhorn No. 3 coal zone has been one of the leading producers in the state of Kentucky and, in some areas, is of very high quality. Bed stratigraphy within the Upper Elkhorn No. 3 zone and coal thickness of the No. 3A coal …


Regional Subsurface Geologic Cross Sections Of The Mississippian System, Appalachian Basin, Eastern Kentucky, David C. Harris, Thomas N. Sparks Jan 2000

Regional Subsurface Geologic Cross Sections Of The Mississippian System, Appalachian Basin, Eastern Kentucky, David C. Harris, Thomas N. Sparks

Map and Chart--KGS

This series of 14 regional cross sections illustrates subsurface stratigraphic correlations of Mississippian (upper Carboniferous) rocks in the Appalachian Basin of eastern Kentucky. These cross sections were constructed as part of a regional stratigraphic study of the Mississippian "Big Lime," a major oil- and gas-producing formation. The series illustrates 10 dip-oriented and 4 strike-oriented lines, extending from the Slade Formation outcrop belt on the northwest, to the state borders on the east and south. Stratigraphic and structural versions are shown for each section to better illustrate thickness and structural variations. These cross sections served as the regional framework during collection …


Improving Turf Through Renovation, A. J. Powell Jr. Jan 2000

Improving Turf Through Renovation, A. J. Powell Jr.

Agriculture and Natural Resources Publications

Turf generally can be improved through proper mowing, fertilizing, watering, and pest control applications. With some turf problems, however, the only solution is re-establishment, using one of two methods:

  • The conventional method, which involves destroying the sod, tilling the soil, and replanting.
  • Renovation, which involves replanting without completely tilling the soil and often without destroying all existing vegetation.

Advantages of conventional tillage over renovation:

  • Control of weeds and undesirable grass may be more complete.
  • Surface depressions or humps can be removed, resulting in a smoother soil surface.
  • Large quantities of organic matter or sand can be mixed into the surface …


Mowing, Dethatching, Coring, And Rolling Kentucky Lawns, A. J. Powell Jr. Jan 2000

Mowing, Dethatching, Coring, And Rolling Kentucky Lawns, A. J. Powell Jr.

Agriculture and Natural Resources Publications

Good lawn care takes more than just mowing and chemical treatments. To develop quality turf, you need correct mowing techniques and may occasionally need to dethatch, core, or roll your lawn.


Turf Care Calendar For Kentucky Bluegrass, Tall Fescue, And Perennial Ryegrass Turf, A. J. Powell Jan 2000

Turf Care Calendar For Kentucky Bluegrass, Tall Fescue, And Perennial Ryegrass Turf, A. J. Powell

Agriculture and Natural Resources Publications

No abstract provided.


Light Backscatter Of Milk Products For Transition Sensing Using Optical Fibers, Frederick A. Payne, Czarena L. Crofcheck, Sue E. Nokes, Klat C. Kang Nov 1999

Light Backscatter Of Milk Products For Transition Sensing Using Optical Fibers, Frederick A. Payne, Czarena L. Crofcheck, Sue E. Nokes, Klat C. Kang

Biosystems and Agricultural Engineering Faculty Publications

Transition sensors are needed, particularly in the dairy industry, for detecting transitions in pipe flow systems from product-to-water or product-to-product (such as from chocolate to vanilla ice cream mix). Transition information is used to automatically sequence valves to minimize product waste. Optical fibers were used to measure light backscatter between 400 and 950 nm as a function of milk concentration in water and milkfat concentration in milk. The normalized response (100% for product and 0% for water) as a function of product concentration in water was approximately logarithmic for skim milk between 400 and 900 nm and approximately linear for …


Runoff From Fescue Plots Treated With Trimec, Cristopher G. Moss, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams Nov 1999

Runoff From Fescue Plots Treated With Trimec, Cristopher G. Moss, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams

Biosystems and Agricultural Engineering Faculty Publications

Runoff of herbicides can promote adverse impacts in receiving waters. The objective of this study was to assess the effects of rainfall delay, herbicide application rate, rainfall intensity, and pre-application rainfall on runoff of TRIMEC (a combination of 2,4-D, dicamba, and mecoprop), a herbicide that is commonly used in central Kentucky. The levels of rainfall delay were 0, 2, and 4 d following application; and the levels of herbicide application rate were 0, 0.5, 1 and 2 times the recommended rate. Simulated rainfall was applied at intensities of 64, 102, and 140 mm h-1; and the depths of …


Hubble Space Telescope/Faint Object Spectrograph Spectroscopy Of Spatially Resolved Narrow-Line Regions In The Seyfert 2 Galaxies Ngc 2110 And Ngc 5929, Pierre Ferruit, Andrew S. Wilson, Mark Whittle, Chris Simpson, John S. Mulchaey, Gary J. Ferland Sep 1999

Hubble Space Telescope/Faint Object Spectrograph Spectroscopy Of Spatially Resolved Narrow-Line Regions In The Seyfert 2 Galaxies Ngc 2110 And Ngc 5929, Pierre Ferruit, Andrew S. Wilson, Mark Whittle, Chris Simpson, John S. Mulchaey, Gary J. Ferland

Physics and Astronomy Faculty Publications

We present the results of UV and optical Hubble Space Telescope/Faint Object Spectrograph spectroscopy of bright, extranuclear regions of line emission in the Seyfert galaxies NGC 2110 and NGC 5929. We have obtained spectra of the brightest region of the ``nuclear jet'' of NGC 2110 (75 pc from the nucleus) and of the southwest emission-line cloud of NGC 5929 (90 pc from the nucleus), in the G130H (1090-1605 Å), G190H (1570-2310 Å), G400H (3235-4780 Å), and G570H (4570-6820 Å) configurations. The observed line ratios are compared with the predictions of the two component (matter- and ionization-bounded, MB-IB), central source …


Modeling Surface And Subsurface Pesticide Transport Under Three Field Conditions Using Przm-3 And Gleams, Robert W. Malone, Richard C. Warner, Stephen R. Workman, Matt E. Byers Sep 1999

Modeling Surface And Subsurface Pesticide Transport Under Three Field Conditions Using Przm-3 And Gleams, Robert W. Malone, Richard C. Warner, Stephen R. Workman, Matt E. Byers

Biosystems and Agricultural Engineering Faculty Publications

Contaminant transport models should be evaluated over a wide range of conditions to determine their limitations. The models PRZM and GLEAMS have been evaluated many times, but few studies are available in which predicted movement in runoff and percolate were simultaneously evaluated against field data. Studies of this type are essential because pesticide leaching and runoff are mutually dependent processes. For this reason, PRZM-3 and GLEAMS were evaluated for their ability to predict metribuzin concentrations in runoff, sediment, subsurface soil, and pan lysimeters under three field conditions (yard waste compost amended, no-till, and conventional-till) on a Lowell silt loam soil. …


Dust Emission From Herbig Ae/Be Stars: Evidence For Disks And Envelopes, Anatoly Miroshnichenko, Željko Ivezić, Dejan Vinković, Moshe Elitzur Aug 1999

Dust Emission From Herbig Ae/Be Stars: Evidence For Disks And Envelopes, Anatoly Miroshnichenko, Željko Ivezić, Dejan Vinković, Moshe Elitzur

Physics and Astronomy Faculty Publications

Infrared and millimeter-wave emission from Herbig Ae/Be stars has produced conflicting conclusions regarding the dust geometry in these objects. We show that the compact dimensions of the millimeter-wave-emitting regions are a decisive indication for disks. But a disk cannot explain the spectral energy distribution unless it is embedded in an extended envelope that (1) dominates the IR emission and (2) provides additional disk heating on top of the direct stellar radiation. Detailed radiative transfer calculations based on the simplest model for envelope-embedded disks successfully fit the data from UV to millimeter wavelengths and show that the disks have central holes. …


The Effects Of Charge Transfer On The Thermal Equilibrium Of Photoionized Nebulae, J. B. Kingdon, Gary J. Ferland May 1999

The Effects Of Charge Transfer On The Thermal Equilibrium Of Photoionized Nebulae, J. B. Kingdon, Gary J. Ferland

Physics and Astronomy Faculty Publications

Charge transfer can affect both the ionization and thermal balance of astrophysical plasmas. Using the most recent rate coefficients and energy defects, we calculate the heating/cooling rates for charge transfer reactions between hydrogen and elements up to Z=30. We incorporate these values into the photoionization code CLOUDY. Results from models approximating a wide range of astrophysical objects and conditions suggest that charge transfer can make a significant contribution to the heating near the H ionization front, particularly in objects with a hard ionizing continuum or enhanced abundances. Charge transfer heating can also be important in regimes in which the usual …


The Pg X-Ray Qso Sample: Links Between The Ultraviolet-X-Ray Continuum And Emission Lines, Beverley J. Wills, A. Laor, M. S. Brotherton, D. Wills, B. J. Wilkes, Gary J. Ferland, Zhaohui Shang Apr 1999

The Pg X-Ray Qso Sample: Links Between The Ultraviolet-X-Ray Continuum And Emission Lines, Beverley J. Wills, A. Laor, M. S. Brotherton, D. Wills, B. J. Wilkes, Gary J. Ferland, Zhaohui Shang

Physics and Astronomy Faculty Publications

Two sets of relationships relate QSO UV to soft X-ray continua with the broad-line region. These are (i) the Baldwin relationships, which are inverse relationships between the broad-line equivalent width and the continuum luminosity, and (ii) Boroson & Green's optical "Principal Component 1'' relationships, linking steeper soft X-ray spectra with narrower Hβ emission, stronger Hβ blue wings, stronger optical Fe II emission, and weaker [O III] λ5007 lines. In order to understand these relationships, we extended the spectra into the UV for 22 QSOs with high-quality soft X-ray spectra. These are from the complete sample of QSOs from the Bright …


Aluminum And Phosphorus Separation: Application To Preparation Of Target From Brain Tissue For 26Al Determination By Accelerator Mass Spectrometry, Russell D. Brauer, J. David Robertson, Pankaj Sharma, Robert A. Yokel Apr 1999

Aluminum And Phosphorus Separation: Application To Preparation Of Target From Brain Tissue For 26Al Determination By Accelerator Mass Spectrometry, Russell D. Brauer, J. David Robertson, Pankaj Sharma, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Acid digested brain containing 4 mg added 27Al was ashed at 1000°C to prepare an Al2O3 target for accelerator mass spectrometry (AMS) analysis of 26Al. A glass-like material usually resulted which was thought to be aluminum (Al) oxyphosphate. The separation of Al and phosphate was investigated. Al, but not phosphate, was bound by a cation exchange resin (AG 50-X8). Hydrofluoric acid eluted the Al from the resin. Removal of phosphate from acid digested brain by this method produced an amorphous material after ashing that was easier to recover from the porcelain crucible and had a …


Megamaser Disks In Active Galactic Nuclei, John F. Kartje, Arieh Königl, Moshe Elitzur Mar 1999

Megamaser Disks In Active Galactic Nuclei, John F. Kartje, Arieh Königl, Moshe Elitzur

Physics and Astronomy Faculty Publications

Recent spectroscopic and VLBI-imaging observations of bright extragalactic H2O maser sources have revealed that the megamaser emission often originates in thin circumnuclear disks near the centers of active galactic nuclei (AGNs). Using general radiative and kinematic considerations and taking account of the observed flux variability, we argue that the maser emission regions are clumpy, a conclusion that is independent of the detailed mechanism (X-ray heating, shocks, etc.) driving the collisionally pumped masers. We examine scenarios in which the clumps represent discrete gas condensations (i.e., clouds) and do not merely correspond to velocity irregularities in the disk. We show …


Marketing Alfalfa Hay: What The Consumer Demands, Tom Keene Feb 1999

Marketing Alfalfa Hay: What The Consumer Demands, Tom Keene

Kentucky Alfalfa and Stored Forage Conference

Anytime we address selling a product to the consumer; our first objective should always be to sell a quality product. However before we get into quality, I think we need to back up and understand that quality can vary from customer to customer depending upon the type of livestock he is feeding. For instance, if you are selling hay to a dairy operation, how is the hay being utilized? Is it being fed free choice? Is it going into a milking TMR (total mixed ration)? Is it going to feed young stock, breeding heifers, or sick animals? Each group of …


How I Produce And Market Alfalfa Hay, John Nowak Feb 1999

How I Produce And Market Alfalfa Hay, John Nowak

Kentucky Alfalfa and Stored Forage Conference

John Nowak was born March 22, 1947, in New York City and was raised in Westchester County, just north of New York City. After graduating from Colorado State University with a B.S. degree in farm and ranch management, he entered the U.S. Army. John served on active duty from 1969 until 1978. In 1975, his Army career brought him to Fort Campbell, Kentucky, and he began farming part-time in Christian County in 1976. As with many "start-from-scratch" farmers, John's first farming efforts involved producing burley tobacco during the years 1976 through 1979. In 1979, he began a cow-calf and backgrounding …