Science.gov

Sample records for fork leonaradian age

  1. Integrated Outcrop and Subsurface Studies of the Interwell Environment of Carbonate Reservoirs: Clear Fork (Leonaradian Age) Reservoirs, West Texas and New Mexico

    SciTech Connect

    Lucia, F.J.; Ruppel, S.C.

    2001-02-01

    Characterization of cycle and facies architecture on lower Clear Fork and lowermost upper Clear Fork equivalent outcrops in Apache Canyon of Sierra Diablo was complete. The focus of detailed study in Apache Canyon has been the upper Clear Fork section because this interval contains the productive interval in South Wasson field, the preliminary subsurface study area. Parts of three high-frequency sequences (HFS), each 60 to 100 ft thick, are present on the south wall of Apache Canyon. HFS's display an upper-deepening or backstepping pattern associated with longer-term sea level rise. Each HFS is composed of upward-shallowing cycles whose thickness, facies composition, and continuity vary within and between HFS's.

  2. Integrated Outcrop and Subsurface Studies of the Interwell Environment of Carbonate Reservoirs: Clear Fork (Leonaradian Age) Reservoirs, West Texas and New Mexico

    SciTech Connect

    Lucia, F. Jerry; Jennings, Jr., James W.

    2001-05-08

    A preliminary reservoir model was constructed for the Lower Clear Fork of the South Wasson Clear Fork reservoir. The model was constructed by calibrating high-frequency cycles observed in cores to the porosity log. The rock fabrics mostly fall in petrophysical class 1, and cross plots of porosity and water saturation could not be used to identify rock fabrics. Data from two limestone fields and one dolostone field were presented to support the contention that grain-dominated fabrics have higher porosity than mud-dominated fabrics do and that this difference is retained when the limestone is dolomitized.

  3. INTEGRATED OUTCROP AND SUBSURFACE STUDIES OF THE INTERWELL ENVIRONMENT OF CARBONATE RESERVOIRS: CLEAR FORK (LEONARADIAN AGE) RESERVOIRS, WEST TEXAS AND NEW MEXICO

    SciTech Connect

    James W. Jennings, Jr.; F. Jerry Lucia

    2001-10-01

    Petrophysical heterogeneity in the South Wasson Clear Fork (SWCF) reservoir and other shallow-water platform carbonates in the Permian Basin and elsewhere is composed of a large-scale stratigraphically controlled component and a small-scale poorly correlated component. The large-scale variability exists as a flow-unit scale petrophysical layering that is laterally persistent at interwell scales and produces highly stratified reservoir behavior. Capturing the rate-enhancing effect of the small-scale variability requires carefully controlled averaging procedures at four levels of scaleup. Porosity can be easily scaled using arithmetic averaging procedures. Permeability, however, requires carefully controlled power-averaging procedures. Effective permeability is increased at every scaleup level.

  4. LAKE FORK

    EPA Science Inventory

    The Lake Fork of the Arkansas River Watershed has been adversely affected through mining, water diversion and storage projects, grazing, logging, and other human influences over the past 120 years. It is the goals of the LFWWG to improve the health of Lake fork by addressing th...

  5. INTEGRATED OUTCROP AND SUBSURFACE STUDIES OF THE INTERWELL ENVIRONMENT OF CARBONATE RESERVOIRS: CLEAR FORK (LEONARDIAN-AGE) RESERVOIRS, WEST TEXAS AND NEW MEXICO

    SciTech Connect

    F. Jerry Lucia

    2002-01-31

    This is the final report of the project ''Integrated Outcrop and Subsurface Studies of the Interwell Environment of Carbonate Reservoirs: Clear Fork (Leonardian-Age) Reservoirs, West Texas and New Mexico'', Department of Energy contract no. DE-AC26-98BC15105 and is the third in a series of similar projects funded jointly by the U.S. Department of Energy and The University of Texas at Austin, Bureau of Economic Geology, Reservoir Characterization Research Laboratory for Carbonates. All three projects focus on the integration of outcrop and subsurface data for the purpose of developing improved methods for modeling petrophysical properties in the interwell environment. The first project, funded by contract no. DE-AC22-89BC14470, was a study of San Andres outcrops in the Algerita Escarpment, Guadalupe Mountains, Texas and New Mexico, and the Seminole San Andres reservoir, Permian Basin. This study established the basic concepts for constructing a reservoir model using sequence-stratigraphic principles and rock-fabric, petrophysical relationships. The second project, funded by contract no. DE-AC22-93BC14895, was a study of Grayburg outcrops in the Brokeoff Mountains, New Mexico, and the South Cowden Grayburg reservoir, Permian Basin. This study developed a sequence-stratigraphic succession for the Grayburg and improved methods for locating remaining hydrocarbons in carbonate ramp reservoirs. The current study is of the Clear Fork Group in Apache Canyon, Sierra Diablo Mountains, West Texas, and the South Wasson Clear Fork reservoir, Permian Basin. The focus was on scales of heterogeneity, imaging high- and low-permeability layers, and the impact of fractures on reservoir performance. In this study (1) the Clear Fork cycle stratigraphy is defined, (2) important scales of petrophysical variability are confirmed, (3) a unique rock-fabric, petrophysical relationship is defined, (4) a porosity method for correlating high-frequency cycles and defining rock-fabric flow layers

  6. Metals-contaminated benthic invertebrates in the Clark Fork River, Montana: Effects on age-0 brown trout and rainbow trout

    USGS Publications Warehouse

    Woodward, Daniel F.; Farag, Aïda M.; Bergman, Harold L.; Delonay, Aaron J.; Little, Edward E.; Smiths, Charlie E.; Barrows, Frederic T.

    1995-01-01

    Benthic organisms in the upper Clark Fork River have recently been implicated as a dietary source of metals that may be a chronic problem for young-of-the-year rainbow trout (Oncorhynchus mykiss). In this present study, early life stage brown trout (Salmo trutta) and rainbow trout were exposed for 88 d to simulated Clark Fork River water and a diet of benthic invertebrates collected from the river. These exposures resulted in reduced growth and elevated levels of metals in the whole body of both species. Concentrations of As, Cd, Cu, and Pb increased in whole brown trout; in rainbow trout, As and Cd increased in whole fish, and As also increased in liver. Brown trout on the metals-contaminated diets exhibited constipation, gut impaction, increased cell membrane damage (lipid peroxidation), decreased digestive enzyme production (zymogen), and a sloughing of intestinal mucosal epithelial cells. Rainbow trout fed the contaminated diets exhibited constipation and reduced feeding activity. We believe that the reduced standing crop of trout in the Clark Fork River results partly from chronic effects of metals contamination in benthic invertebrates that are important as food for young-of-the-year fish.

  7. Cosmogenic Surface-Exposure Age Limits for Latest-Pleistocene Glaciation and Paleoclimatic Inferences in the American Fork Canyon, Wasatch Mountains, Utah, U.S.A.

    NASA Astrophysics Data System (ADS)

    Laabs, B. J.; Bash, E. R.; Refsnider, K. A.; Becker, R. A.; Munroe, J. S.; Mickelson, D. M.; Singer, B. S.

    2007-12-01

    The Wasatch Mountains of north-central Utah bordered the eastern shore of Lake Bonneville and were occupied by numerous valley glaciers during the latest Pleistocene. Stratigraphic and morphostratigraphic observations near the mouths of Little Cottonwood and Bells Canyons reveal that glaciers in these two valleys began constructing terminal moraines before Lake Bonneville reached its maximum shoreline elevation at about 19-17 cal. ka. Although the chronology of the lake highstand is well constrained by numerous radiocarbon dates, the timing of deglaciation in the Wasatch Mountains is relatively unclear. Moreover, there is considerable disagreement over the climatic conditions (cold/dry vs. cool/wet) that led to the expansion of glaciers and the lake. To address these issues, we explore the glacial record in the American Fork canyon by combining field mapping with cosmogenic 10Be surface-exposure dating and numerical modeling of glacier mass balance and ice flow to limit the extent, timing and climate of the last glaciation in the Wasatch Mountains. Six of ten cosmogenic surface-exposure ages from a terminal moraine in the canyon are tightly clustered (ranging from 14.4 ± 1.3 to 15.2 ± 1.1 ka; 2σ analytical error) and yield an error-weighted mean age of 14.8 ± 0.4 ka (2σ, MSWD = 0.26; individual age calculations based on a high latitude/sea level production rate of 4.98 ± 0.34 atoms g SiO2-1 yr-1 scaled for elevation and latitude). This age is consistent with previously reported cosmogenic-exposure dates from elsewhere in the range, and suggests that ice retreat in the Wasatch Mountains began as much as 4 kyr later than in other Rocky Mountain ranges and was in phase with the hydrologic fall of Lake Bonneville from the Provo shoreline. Numerical glacier modeling experiments (based on methods of Plummer and Phillips, 2003) simulate maximum ice extent in the American Fork, Little Cottonwood and Dry Creek canyons under a broad range of potential temperature and

  8. 3. SOUTH FORK OF THE TULE RIVER MIDDLE FORK BRANCH ...

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

    3. SOUTH FORK OF THE TULE RIVER MIDDLE FORK BRANCH FLUME AT THE NORTH FORK OF THE TULE RIVER MIDDLE FORK CROSSING SHOWING ORIGINAL DIMENSIONAL STONE PIER ON WEST BANK AT PHOTO CENTER, AND REMAINS OF ORIGINAL EAST BANK DIMENSIONAL STONE PIER AT PHOTO LEFT BELOW NEW (ca. 1931) EAST BANK PIER. VIEW TO SOUTHEAST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA

  9. Taking the thrombin "fork".

    PubMed

    Mann, Kenneth G

    2010-07-01

    The proverb that probably best exemplifies my career in research is attributable to Yogi Berra (http://www.yogiberra.com/), ie, "when you come to a fork in the road ... take it." My career is a consequence of chance interactions with great mentors and talented students and the opportunities provided by a succession of ground-breaking improvements in technology. PMID:20554951

  10. Replication-Fork Dynamics

    PubMed Central

    Duderstadt, Karl E.; Reyes-Lamothe, Rodrigo; van Oijen, Antoine M.; Sherratt, David J.

    2014-01-01

    The proliferation of all organisms depends on the coordination of enzymatic events within large multiprotein replisomes that duplicate chromosomes. Whereas the structure and function of many core replisome components have been clarified, the timing and order of molecular events during replication remains obscure. To better understand the replication mechanism, new methods must be developed that allow for the observation and characterization of short-lived states and dynamic events at single replication forks. Over the last decade, great progress has been made toward this goal with the development of novel DNA nanomanipulation and fluorescence imaging techniques allowing for the direct observation of replication-fork dynamics both reconstituted in vitro and in live cells. This article reviews these new single-molecule approaches and the revised understanding of replisome operation that has emerged. PMID:23881939

  11. 3. View of Clark Fork Vehicle Bridge facing southwest. Bridge ...

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

    3. View of Clark Fork Vehicle Bridge facing southwest. Bridge from north shore of Clark Fork River. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  12. 4. View of Clark Fork Vehicle Bridge facing northeast. Bridge ...

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

    4. View of Clark Fork Vehicle Bridge facing northeast. Bridge from south shoreof Clark Fork River showing 4 spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  13. 2. View of Clark Fork Vehicle Bridge facing northeast. Bridge ...

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

    2. View of Clark Fork Vehicle Bridge facing northeast. Bridge from south shore of Clark Fork River showing 4 1/2 spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  14. 1. View of Clark Fork Vehicle Bridge facing west. Panorama ...

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

    1. View of Clark Fork Vehicle Bridge facing west. Panorama showing the entire span of bridge from north shore of the Clark Fork River. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  15. 7. View of Clark Fork Vehicle Bridge facing northwest. Bridge ...

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

    7. View of Clark Fork Vehicle Bridge facing northwest. Bridge from south shore of Clark Fork River showing 4 1/2 spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  16. Tuning Forks and Monitor Screens.

    ERIC Educational Resources Information Center

    Harrison, M. A. T.

    2000-01-01

    Defines the vibrations of a tuning fork against a computer monitor screen as a pattern that can illustrate or explain physical concepts like wave vibrations, wave forms, and phase differences. Presents background information and demonstrates the experiment. (Author/YDS)

  17. 22. View of Clark Fork Vehicle Bridge facing downwest side. ...

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

    22. View of Clark Fork Vehicle Bridge facing down-west side. Looking at road deck and vertical laced channel. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  18. 11. View of Clark Fork Vehicle Bridge facing northwest. Southernmost ...

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

    11. View of Clark Fork Vehicle Bridge facing northwest. Southernmost span. Plaque was originally located where striped traffic sign is posted. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  19. 19. View of Clark Fork Vehicle Bridge facing north. Looking ...

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

    19. View of Clark Fork Vehicle Bridge facing north. Looking at north abutment and underside of northernmost span. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  20. 20. View of Clark Fork Vehicle Bridge facing up. Looking ...

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

    20. View of Clark Fork Vehicle Bridge facing up. Looking at understructure of northernmost span. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  1. 8. View of Clark Fork Vehicle Bridge facing southwest. Looking ...

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

    8. View of Clark Fork Vehicle Bridge facing southwest. Looking at understructure of northernmost span. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  2. 12. View of Clark Fork Vehicle Bridge facing south. Approach ...

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

    12. View of Clark Fork Vehicle Bridge facing south. Approach from the north road. Plaque was originally located where striped traffic sign is posted. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  3. 21. View of Clark Fork Vehicle Bridge facing west. Looking ...

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

    21. View of Clark Fork Vehicle Bridge facing west. Looking at bridge deck, guard rail, juncture of two bridge spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  4. 18. View of Clark Fork Vehicle Bridge facing north. Looking ...

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

    18. View of Clark Fork Vehicle Bridge facing north. Looking at north concrete abutment and timber stringers. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  5. 21 CFR 882.1525 - Tuning fork.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Tuning fork. 882.1525 Section 882.1525 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1525 Tuning fork. (a) Identification. A tuning fork is a mechanical device...

  6. 5. View of Clark Fork Vehicle Bridge facing east. Bridge ...

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

    5. View of Clark Fork Vehicle Bridge facing east. Bridge from south shore of Clark Fork River-southernmost span. 1900-era Northern Pacific Railway Bridge in background. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  7. 16 CFR 1512.13 - Requirements for front fork.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.13 Requirements for front fork. The front fork shall... fork test, § 1512.18(k)(1), without visible evidence of fracture. Sidewalk bicycles need not meet...

  8. 16 CFR 1512.13 - Requirements for front fork.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.13 Requirements for front fork. The front fork shall... fork test, § 1512.18(k)(1), without visible evidence of fracture. Sidewalk bicycles need not meet...

  9. 16 CFR 1512.13 - Requirements for front fork.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.13 Requirements for front fork. The front fork shall... fork test, § 1512.18(k)(1), without visible evidence of fracture. Sidewalk bicycles need not meet...

  10. 16 CFR 1512.13 - Requirements for front fork.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.13 Requirements for front fork. The front fork shall... fork test, § 1512.18(k)(1), without visible evidence of fracture. Sidewalk bicycles need not meet...

  11. 16 CFR 1512.13 - Requirements for front fork.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.13 Requirements for front fork. The front fork shall... fork test, § 1512.18(k)(1), without visible evidence of fracture. Sidewalk bicycles need not meet...

  12. Research reactor fork users manual

    SciTech Connect

    Hsue, S.T.; Menlove, H.O.; Bosler, G.E.; Dye, H.R.; Walton, G.; Halbig, J.K.; Siebelist, R.

    1993-11-01

    This manual describes the design features and operating characteristics of the research reactor fork. The system includes an ion chamber for gross gamma-ray counting, fission chambers for neutron counting, and a collimated high-resolution spectroscopy system for gamma-ray measurements. The neutron and ion chamber measurements are designed to be made underwater in spent-fuel cooling ponds. The neutron and gamma-ray detectors have been designed with high efficiencies to accommodate the relatively low emission rates of neutrons and gamma rays from low-burnup, research-type reactor fuel. This manual presents the design, performance, and test results for the system.

  13. Training Guidelines: Fork Lift Truck Driving.

    ERIC Educational Resources Information Center

    Ceramics, Glass, and Mineral Products Industry Training Board, Harrow (England).

    This manual of operative training guidelines for fork lift truck driving has been developed by the Ceramics, Glass and Mineral Products Industry Training Board (Great Britain) in consultation with a number of firms which manufacture fork lift trucks or which already have training--programs for their use. The purpose of the guidelines is to assist…

  14. Fifth-wheel fork truck adapter

    NASA Technical Reports Server (NTRS)

    Smith, P. L.

    1969-01-01

    Standard fifth wheel mounted on a rectangular steel structure adapted for use with a fork lift truck provides a fast, safe, and economical way of maneuvering semitrailers in close quarters at plants and warehouses. One operator can move and locate a semitrailer without dismounting from a fork lift truck.

  15. South Fork Holston River basin 1988 biomonitoring

    SciTech Connect

    Saylor, C.F.; Ahlstedt, S.A.

    1990-06-01

    There is concern over the effects of shifts in land use use practices on the aquatic fauna of streams in the South Fork Holston River basin in northwestern North Carolina and southwestern Virginia. Trout reproduction has noticeably declined in the Watauga River subbasin. The Watauga River and Elk River subbasins have been subjected to commercial and resort development. The Middle fork Holston River and the upper South Fork Holston River subbasins have been affected by agricultural and mining activities, respectively (Cox, 1986). To aid reclamation and management of the South Fork Holston basin, Tennessee Valley Authority (TVA) biologists conducted biomonitoring--including index of biotic integrity and macroinvertebrate sampling--on the Middle Fork Holston, South Fork Holston, Watauga, and Elk Rivers to assess cumulative impairment related to changes in habitat and pollutant loading in these subbasins. Biomonitoring can detect environmental degradation, help document problem areas, and assist in development of strategies for managing water quality. This report discusses the methods and materials and results of the biomonitoring of South Fork Holston River Basin. 13 refs., 5 figs., 12 tabs.

  16. 13. View of Clark Fork Vehicle Bridge facing south. Concrete ...

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

    13. View of Clark Fork Vehicle Bridge facing south. Concrete barrier blocks access. Plaque was originally located where strioed traffic sign is posted at right. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  17. 14. View of Clark Fork Vehicle Bridge facing north. Approach ...

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

    14. View of Clark Fork Vehicle Bridge facing north. Approach from the south. Concrete barrier blocks access. Plaque was originally located where striped traffic sign is posted at right. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  18. 24. View of one of the plaques from Clark Fork ...

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

    24. View of one of the plaques from Clark Fork Vehicle Bridge. Presently located at the Bonner County Historical Museum in Sandpoint, Idaho. A plaque was attached at each end of the bridge. Only one remains. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  19. 23. View of Clark Fork Vehicle Bridge facing upwest side. ...

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

    23. View of Clark Fork Vehicle Bridge facing up-west side. Looking at structural connection of top chord, vertical laced channel and diagonal bars. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  20. WRNIP1 protects stalled forks from degradation and promotes fork restart after replication stress.

    PubMed

    Leuzzi, Giuseppe; Marabitti, Veronica; Pichierri, Pietro; Franchitto, Annapaola

    2016-07-01

    Accurate handling of stalled replication forks is crucial for the maintenance of genome stability. RAD51 defends stalled replication forks from nucleolytic attack, which otherwise can threaten genome stability. However, the identity of other factors that can collaborate with RAD51 in this task is poorly elucidated. Here, we establish that human Werner helicase interacting protein 1 (WRNIP1) is localized to stalled replication forks and cooperates with RAD51 to safeguard fork integrity. We show that WRNIP1 is directly involved in preventing uncontrolled MRE11-mediated degradation of stalled replication forks by promoting RAD51 stabilization on ssDNA We further demonstrate that replication fork protection does not require the ATPase activity of WRNIP1 that is however essential to achieve the recovery of perturbed replication forks. Loss of WRNIP1 or its catalytic activity causes extensive DNA damage and chromosomal aberrations. Intriguingly, downregulation of the anti-recombinase FBH1 can compensate for loss of WRNIP1 activity, since it attenuates replication fork degradation and chromosomal aberrations in WRNIP1-deficient cells. Therefore, these findings unveil a unique role for WRNIP1 as a replication fork-protective factor in maintaining genome stability. PMID:27242363

  1. Effects of rainbow trout fry of a metals-contaminated diet of benthic invertebrates from the Clark Fork River, Montana

    SciTech Connect

    Woodward, D.F. ); Brumbaugh, W.G.; DeLonay, A.J.; Little, E.E. ); Smith, C.E. )

    1994-01-01

    The upper Clark Fork River in northwestern Montana has received mining wastes from the Butte and Anaconda areas since 1880. These wastes have contaminated areas of the river bed and floodplain with tailings and heavy metal sludge, resulting in elevated concentration of metals in surface water, sediments, and biota. Rainbow trout Oncorhynchus mykiss were exposed immediately after hatching for 91 d to cadmium, copper, lead, and zinc in water at concentrations simulating those in Clark Fork River. From exogenous feeding (21 d posthatch) through 91 d, fry were also fed benthic invertebrates from the Clark Fork River that contained elevated concentrations of arsenic, cadmium, copper, and lead. Evaluations of different combinations of diet and water exposure indicated diet-borne metals were more important than water-borne metals - at the concentrations we tested - in reducing survival and growth of rainbow trout. Whole-body metal concentrations ([mu]g/g, wet weight) at 91 d in fish fed Clark Fork invertebrates without exposure to Clark Fork water were arsenic, 1.4; cadmium, 0.16; and copper, 6.7. These were similar to concentrations found in Clark Fork River fishes. Livers from fish on the high-metals diets exhibited degenerative changes and generally lacked glycogen vacuolation. Indigenous Clark Fork River invertebrates provide a concentrated source of metals for accumulation into young fishes, and probably were the cause of decreased survival and growth of age-0 rainbow trout in our laboratory exposures. 30 refs., 8 figs., 4 tabs.

  2. Stability of blocked replication forks in vivo

    PubMed Central

    Mettrick, Karla A.; Grainge, Ian

    2016-01-01

    Replication of chromosomal DNA must be carried out to completion in order for a cell to proliferate. However, replication forks can stall during this process for a variety of reasons, including nucleoprotein ‘roadblocks’ and DNA lesions. In these circumstances the replisome copying the DNA may disengage from the chromosome to allow various repair processes to restore DNA integrity and enable replication to continue. Here, we report the in vivo stability of the replication fork when it encounters a nucleoprotein blockage in Escherichia coli. Using a site-specific and reversible protein block system in conjunction with the temperature sensitive DnaC helicase loader and DnaB replicative helicase, we monitored the disappearance of the Y-shaped DNA replication fork structures using neutral-neutral 2D agarose gels. We show the replication fork collapses within 5 min of encountering the roadblock. Therefore, the stalled replication fork does not pause at a block in a stable confirmation for an extended period of time as previously postulated. PMID:26490956

  3. South Fork Latrine showing north and west sides, general view ...

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

    South Fork Latrine showing north and west sides, general view to southeast - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  4. South Fork Latrine, oblique view showing south and east sides; ...

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

    South Fork Latrine, oblique view showing south and east sides; view northwest - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  5. South Fork Latrine, east elevation showing structure in context, view ...

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

    South Fork Latrine, east elevation showing structure in context, view west - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  6. 6. Roaring Fork Motor Nature Trail, road view after stop ...

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

    6. Roaring Fork Motor Nature Trail, road view after stop four. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  7. 9. Roaring Fork Motor Nature Trail, Reagan House. Great ...

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

    9. Roaring Fork Motor Nature Trail, Reagan House. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  8. 8. Roaring Fork Motor Nature Trail, handbuilt rock pile. ...

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

    8. Roaring Fork Motor Nature Trail, hand-built rock pile. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  9. 5. Roaring Fork Motor Nature Trail, vista at stop three. ...

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

    5. Roaring Fork Motor Nature Trail, vista at stop three. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  10. 1. Roaring Fork Motor Nature Trail, entrance sign. Great ...

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

    1. Roaring Fork Motor Nature Trail, entrance sign. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  11. 3. Roaring Fork Motor Nature Trail, view between second and ...

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

    3. Roaring Fork Motor Nature Trail, view between second and third stops - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  12. 2. Roaring Fork Motor Nature Trail, road view before first ...

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

    2. Roaring Fork Motor Nature Trail, road view before first stop. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  13. 7. Roaring Fork Motor Nature Trail, rocks along edge of ...

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

    7. Roaring Fork Motor Nature Trail, rocks along edge of road. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  14. Roaring Fork Motor Nature Trail, Title Sheet Great Smoky ...

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

    Roaring Fork Motor Nature Trail, Title Sheet - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  15. 12. Roaring Fork Motor Nature Trail, place of a thousand ...

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

    12. Roaring Fork Motor Nature Trail, place of a thousand drips, view from road. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  16. 11. Roaring Fork Motor Nature Trail, boulders along road after ...

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

    11. Roaring Fork Motor Nature Trail, boulders along road after stop 13. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  17. 15. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM, LEFT FORK TO ...

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

    15. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM, LEFT FORK TO SETTLING BASIN, SHOWING RIGHT FORK WITH GATE IN PLACE AND A FEW NEEDLES IN PLACE - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  18. Pathological Changes of von Economo Neuron and Fork Neuron in Neuropsychiatric Diseases.

    PubMed

    Liu, Jia; Wang, Lu-ning; Arzberger, Thomas; Zhu, Ming-wei

    2016-02-01

    von Economo neuron (VEN) is a bipolar neuron characterized by a large spindle-shaped soma. VEN is generally distributed in the layer V of anterior insular lobe and anterior cingulate cortex. Fork neuron is another featured bipolar neuron. In recent years,many studies have illustrated that VEN and fork neurons are correlated with complicated cognition such as self-consciousness and social emotion. Studies in the development and morpholigies of these two neurons as well as their pathological changes in various neurological and psychiatric disorders have found that the abnormal number and functions of VEN can cause corresponding dysfunctions in social recognition and emotions both during the neuro-developmental stages of childhood and during the nerve degeneration in old age stage. Therefore, more attentions should be paid on the research of VEN and fork neurons in neuropsychiatric diseases. PMID:26996211

  19. Retained garden fork following cranial stab injury

    PubMed Central

    Gonya, Sonwabile; Mbatha, Andile; Moyeni, Nondabula; Enicker, Basil

    2016-01-01

    Retained garden fork is a rare complication of penetrating cranial trauma. Retained knife blade is the most commonly reported presentation. We report an unusual case of a 30-year-old male patient treated at our institution, who presented with a retained garden fork following a stab to the head, with no associated neurological deficits. Computerized tomographic scan of the brain was performed preoperatively to assess the trajectory of the weapon and parenchymal injury. A craniectomy was performed to facilitate removal of the weapon in the operating theatre under general anaesthesia. Intravenous prophylactic antibiotics were administered pre- and postoperatively to prevent septic complications. The patient recovered well and was discharged home. PMID:26747398

  20. 27 CFR 9.113 - North Fork of Long Island.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false North Fork of Long Island... North Fork of Long Island. (a) Name. The name of the viticultural area described in this section is “North Fork of Long Island.” (b) Approved maps. The appropriate maps for determining the boundaries...

  1. 27 CFR 9.113 - North Fork of Long Island.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false North Fork of Long Island... North Fork of Long Island. (a) Name. The name of the viticultural area described in this section is “North Fork of Long Island.” (b) Approved maps. The appropriate maps for determining the boundaries...

  2. 27 CFR 9.113 - North Fork of Long Island.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false North Fork of Long Island... North Fork of Long Island. (a) Name. The name of the viticultural area described in this section is “North Fork of Long Island.” (b) Approved maps. The appropriate maps for determining the boundaries...

  3. 27 CFR 9.113 - North Fork of Long Island.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false North Fork of Long Island... North Fork of Long Island. (a) Name. The name of the viticultural area described in this section is “North Fork of Long Island.” (b) Approved maps. The appropriate maps for determining the boundaries...

  4. 27 CFR 9.113 - North Fork of Long Island.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false North Fork of Long Island... North Fork of Long Island. (a) Name. The name of the viticultural area described in this section is “North Fork of Long Island.” (b) Approved maps. The appropriate maps for determining the boundaries...

  5. Environment of deposition of Clear Fork Formation: Yoakum County, Texas

    SciTech Connect

    Moore, B.K.

    1987-05-01

    The Clear Fork Formation is Permian (Leonardian) in age and constitutes a major oil-bearing unit in the Permian basin of west Texas. In Yoakum County, west Texas, the upper Clear Fork carbonates record a subtidal upward-shoaling sequence of deposition. A small bryozoan-algal patch reef is situated within these carbonates near the southern edge of the North Basin platform. The reef is completely dolomitized, but paramorphic replacement has facilitated a study of the paleoecology, lateral variations, and community succession within this buildup. Build-ups of this type are scarcely known in strata of Permian age. The reef was apparently founded on a coquina horizon at the base of the buildup. The reef apparently had a low-relief, dome-shaped morphology. The trapping and binding of sediment by bryozoa appear to have been the main constructional process. A significant role was also played by encrusting forams and the early precipitation of submarine cements, both of which added rigidity to the structure. The reef also contains a low-diversity community of other invertebrates. Algal constituents predominate at the basinward edge of the buildup. The reef was formed entirely subaqueously on a broad, relatively shallow tropical marine carbonate shelf environment. An understanding of the lithofacies distribution and paragenesis within this sequence will provide information on porosity variations and the nature and distribution of permeability barriers. Such information is useful in reservoir modeling studies and for secondary recovery techniques in shelf-edge carbonate reservoirs of this type.

  6. 21 CFR 882.1525 - Tuning fork.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tuning fork. 882.1525 Section 882.1525 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... and to test for vibratory sense. (b) Classification. Class I (general controls). The device is...

  7. 21 CFR 882.1525 - Tuning fork.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Tuning fork. 882.1525 Section 882.1525 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... is a mechanical device which resonates at a given frequency and is used to diagnose hearing...

  8. Development of the Pintle Release Fork Mechanism

    SciTech Connect

    BOGER, R.M.; DALE, R.

    1999-08-27

    An improved method of attachment of the pintle to the piston in the universal sampler is being developed. The mechanism utilizes a forked release disk which captures two balls in a cavity formed by a hole in the piston and a groove in the pintle rod.

  9. Man-induced gradient adjustment of the South Fork Forked Deer River, west Tennessee

    USGS Publications Warehouse

    Simon, A.; Robbins, C.H.

    1987-01-01

    Channel modifications from 1968 to 1969 on the South Fork Forked Deer River in western Tennessee have caused upstream degradation, downstream aggradation, and bank failures along the altered channels, adjacent reaches, and tributaries. The result of these adjustments is a general decrease in gradient as the channel attempts to absorb the imposed increase in energy conditions created by channelization. Headward degradation at a rate of approximately 2.57 km/yr on the South Fork Forked Deer River caused from 1.52 m to about 3.14 m of incision over a 13.5 km reach from 1969 to 1981. As a consequence of substantially increased sediment supply, approximately 2.13 m of aggradation was induced downstream of this reach during the same period. This accumulation represents a 60% recovery of bed level at the downstream site since the completion of channel work in 1969. Gradient adjustment with time is described by exponential decay functions. The length of time required for adjustment to some new quasi-equilibrium condition is computed by these decay functions and is about 20 years from the completion of channel work. Adjusted slopes are less than predisturbed values, probably because straightened channels dissipate less energy by friction, allowing more energy for sediment transport. An equivalent sediment load, therefore, can be transported at a considerably gentler slope. The predisturbed slope exceeds the adjusted slope by an order of magnitude on the downstream reach of the South Fork Forked Deer River. ?? 1987 Springer-Verlag New York Inc.

  10. Geohydrologic appraisal of water resources of the South Fork, Long Island, New York

    USGS Publications Warehouse

    Nemickas, Bronius; Koszalka, Edward J.

    1982-01-01

    The ground-water resources of the South Fork of Long Island, N.Y., were investigated from April 1974 to September 1977. The study area encompasses 137 square miles and includes the eastern part of the Town of Southampton and the entire Town of East Hampton. The South Fork consists of a Paleozoic basement complex that is overlain by Cretaceous and Pleistocene sediments. The surficial material is composed of Late Wisconsinan glacial and glaciofluvial deposits in association with beach and marsh deposits of Recent age. Till underlies most of the eastern part of the South Fork. Precipitation is the sole source of fresh ground water on the South Fork. Average annual precipitation recorded at Bridgehampton from 1931-76 is 45 inches; about half this amount reaches the ground-water reservoir. It is estimated that overland runoff amounts to 0.5 inches per year, and evapotranspiration is 23 inches per year. Thus, recharge equals approximately 22 inches per year. Hydraulic conductivity and transmissivity of the Magothy (Cretaceous) and upper glacial (Pleistocene) aquifers on the South Fork were estimated from aquifer tests and specific-capacity data. The average horizontal hydraulic conductivity of the Magothy aquifer is 70 feet per day, and of the upper glacial aquifer 350 feet per day. Transmissivity of the Magothy aquifer on the South Fork ranges from 600 to 24,100 feet squared per day; transmissivity of the upper glacial aquifer ranges from 5,400 feet to 22,700 feet squared per day. No potable water is available from the underlying Lloyd aquifer. The position of the freshwater to saline-water interface is depicted in maps. In the southern part of the area, the freshwater reservoir follows the Ghyben-Herzberg principle, but in the northern part, the depth to interface is less than expected owing to a greater degree of anisotropy of the geologic units. Total public-supply pumpage on the South Fork is estimated to be about 3 Mgal/day, (million gallons per day). Public

  11. Quartz tuning fork based microwave impedance microscopy

    NASA Astrophysics Data System (ADS)

    Cui, Yong-Tao; Ma, Eric Yue; Shen, Zhi-Xun

    2016-06-01

    Microwave impedance microscopy (MIM), a near-field microwave scanning probe technique, has become a powerful tool to characterize local electrical responses in solid state samples. We present the design of a new type of MIM sensor based on quartz tuning fork and electrochemically etched thin metal wires. Due to a higher aspect ratio tip and integration with tuning fork, such design achieves comparable MIM performance and enables easy self-sensing topography feedback in situations where the conventional optical feedback mechanism is not available, thus is complementary to microfabricated shielded stripline-type probes. The new design also enables stable differential mode MIM detection and multiple-frequency MIM measurements with a single sensor.

  12. The E. coli DNA Replication Fork.

    PubMed

    Lewis, J S; Jergic, S; Dixon, N E

    2016-01-01

    DNA replication in Escherichia coli initiates at oriC, the origin of replication and proceeds bidirectionally, resulting in two replication forks that travel in opposite directions from the origin. Here, we focus on events at the replication fork. The replication machinery (or replisome), first assembled on both forks at oriC, contains the DnaB helicase for strand separation, and the DNA polymerase III holoenzyme (Pol III HE) for DNA synthesis. DnaB interacts transiently with the DnaG primase for RNA priming on both strands. The Pol III HE is made up of three subassemblies: (i) the αɛθ core polymerase complex that is present in two (or three) copies to simultaneously copy both DNA strands, (ii) the β2 sliding clamp that interacts with the core polymerase to ensure its processivity, and (iii) the seven-subunit clamp loader complex that loads β2 onto primer-template junctions and interacts with the α polymerase subunit of the core and the DnaB helicase to organize the two (or three) core polymerases. Here, we review the structures of the enzymatic components of replisomes, and the protein-protein and protein-DNA interactions that ensure they remain intact while undergoing substantial dynamic changes as they function to copy both the leading and lagging strands simultaneously during coordinated replication. PMID:27241927

  13. BALD ROCK AND MIDDLE FORK FEATHER RIVER ROADLESS AREAS, CALIFORNIA.

    USGS Publications Warehouse

    Sorensen, Martin L.; Buehler, Alan R.

    1984-01-01

    The results of a mineral-resource assessment of the Bald Rock and Middle Fork Feather River Roadless Areas in California indicate several areas within the Middle Fork Feather River Roadless Area that have probable mineral-resource potential. A probable potential for placer gold exists at various localities, both in areas covered by Tertiary volcanic rocks and in small streams that drain into the Middle Fork of the Feather River. A probable potential for small deposits of chromite exists in tracts underlain by ultramafic rocks in the Melones fault zone. A probable potential for lead-silver deposits is recognized at the east end of the Middle Fork Feather River Roadless Area.

  14. Evolution of tail fork depth in genus Hirundo.

    PubMed

    Hasegawa, Masaru; Arai, Emi; Kutsukake, Nobuyuki

    2016-02-01

    A classic example of a sexually selected trait, the deep fork tail of the barn swallow Hirundo rustica is now claimed to have evolved and be maintained mainly via aerodynamic advantage rather than sexually selected advantage. However, this aerodynamic advantage hypothesis does not clarify which flight habits select for/against deep fork tails, causing diversity of tail fork depth in hirundines. Here, by focusing on the genus Hirundo, we investigated whether the large variation in tail fork depth could be explained by the differential flight habits. Using a phylogenetic comparative approach, we found that migrant species had deeper fork tails, but less colorful plumage, than the other species, indicating that migration favors a specific trait, deep fork tails. At the same time, tail fork depth but not plumage coloration decreased with increasing bill size - a proxy of prey size, suggesting that foraging on larger prey items favors shallower fork tails. Variation of tail fork depth in the genus Hirundo may be explained by differential flight habits, even without assuming sexual selection. PMID:26865972

  15. South Fork Telephone Switchboard Building, general view in setting showing ...

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

    South Fork Telephone Switchboard Building, general view in setting showing (N) side; view (S) - Fort McKinley, South Fork Telephone Switchboard Building, South side of Weymouth Way, approximately 100 feet west of East Side Drive, Great Diamond Island, Portland, Cumberland County, ME

  16. South Fork Latrine, interior showing head with steel tank mounted ...

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

    South Fork Latrine, interior showing head with steel tank mounted to wall; view south - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  17. South Fork Telephone Switchboard Building, interior west room showing hardwood ...

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

    South Fork Telephone Switchboard Building, interior west room showing hardwood floor; view south - Fort McKinley, South Fork Telephone Switchboard Building, South side of Weymouth Way, approximately 100 feet west of East Side Drive, Great Diamond Island, Portland, Cumberland County, ME

  18. South Fork Telephone Switchboard Building, oblique view of (W) and ...

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

    South Fork Telephone Switchboard Building, oblique view of (W) and (S) sides, view to northeast - Fort McKinley, South Fork Telephone Switchboard Building, South side of Weymouth Way, approximately 100 feet west of East Side Drive, Great Diamond Island, Portland, Cumberland County, ME

  19. South Fork Telephone Switchboard Building, oblique view of east side; ...

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

    South Fork Telephone Switchboard Building, oblique view of east side; view northwest - Fort McKinley, South Fork Telephone Switchboard Building, South side of Weymouth Way, approximately 100 feet west of East Side Drive, Great Diamond Island, Portland, Cumberland County, ME

  20. 14. Roaring Fork Motor Nature Trail, Place of a thousand ...

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

    14. Roaring Fork Motor Nature Trail, Place of a thousand drips, view with three culvert pipes. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  1. 27 CFR 9.65 - North Fork of Roanoke.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false North Fork of Roanoke. 9.65 Section 9.65 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.65 North Fork of Roanoke. (a) Name. The name...

  2. A fork-clearing role for UvrD.

    PubMed

    Florés, Maria-José; Sanchez, Nicolas; Michel, Bénédicte

    2005-09-01

    The inactivation of a replication protein causes the disassembly of the replication machinery and creates a need for replication reactivation. In several replication mutants, restart occurs after the fork has been isomerized into a four-armed junction, a reaction called replication fork reversal. The repair helicase UvrD is essential for replication fork reversal upon inactivation of the polymerase (DnaE) or the beta-clamp (DnaN) subunits of the Escherichia coli polymerase III, and for the viability of dnaEts and dnaNts mutants at semi-permissive temperature. We show here that the inactivation of recA, recFOR, recJ or recQ recombination genes suppresses the requirement for UvrD for replication fork reversal and suppresses the lethality conferred by uvrD inactivation to Pol IIIts mutants at semi-permissive temperature. We propose that RecA binds inappropriately to blocked replication forks in the dnaEts and dnaNts mutants in a RecQ- RecJ- RecFOR-dependent way and that UvrD acts by removing RecA or a RecA-made structure, allowing replication fork reversal. This work thus reveals the existence of a futile reaction of RecA binding to blocked replication forks, that requires the action of UvrD for fork-clearing and proper replication restart. PMID:16135232

  3. 33 CFR 207.370 - Big Fork River, Minn.; logging.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Big Fork River, Minn.; logging..., DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.370 Big Fork River, Minn.; logging. (a) During the season... maintained at all times for the navigation of steamboats, flatboats, and other small craft. (b) A...

  4. 33 CFR 207.370 - Big Fork River, Minn.; logging.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Big Fork River, Minn.; logging..., DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.370 Big Fork River, Minn.; logging. (a) During the season... maintained at all times for the navigation of steamboats, flatboats, and other small craft. (b) A...

  5. 33 CFR 207.370 - Big Fork River, Minn.; logging.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Big Fork River, Minn.; logging..., DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.370 Big Fork River, Minn.; logging. (a) During the season... maintained at all times for the navigation of steamboats, flatboats, and other small craft. (b) A...

  6. 33 CFR 207.370 - Big Fork River, Minn.; logging.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Big Fork River, Minn.; logging..., DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.370 Big Fork River, Minn.; logging. (a) During the season... maintained at all times for the navigation of steamboats, flatboats, and other small craft. (b) A...

  7. 33 CFR 207.370 - Big Fork River, Minn.; logging.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Big Fork River, Minn.; logging..., DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.370 Big Fork River, Minn.; logging. (a) During the season... maintained at all times for the navigation of steamboats, flatboats, and other small craft. (b) A...

  8. Design of a tuning-fork gyro made of quartz

    NASA Astrophysics Data System (ADS)

    Jia, Yubin; Sun, Yunan; Qin, BingKun; Cui, Fang; Chen, Gang

    1998-08-01

    Based on piezoelectric effect of quartz, a design of tuning- fork gyroscopes made of quartz was presented in this paper. The gyroscope is a kind of micro-machined quartz angular rate sensor. Its structure is similar to a tuning fork in quartz watch. In the gyroscope, the piezoelectric effect in quartz is used both to excite a reference vibration in the plane of tuning fork and to detect a vibration normal to this plane due to an externally applied rotation. The amplitude of the second vibration is directly proportional to the angular velocity of the applied rotation. In contrast to ordinary types of tuning fork gyroscopes, this gyroscope uses a single piece of quartz, the sensor element is of a design in which the only vibrationally, active areas are the tines of the tuning fork.

  9. Late Cretaceous Middle Fork caldera and its resurgent granite porphyry intrusion, east-central Alaska

    NASA Astrophysics Data System (ADS)

    Bacon, C. R.; Dusel-Bacon, C.; Aleinikoff, J. N.; Slack, J. F.

    2012-12-01

    Named for the Middle Fork of the North Fork of the Fortymile River, the Middle Fork caldera encompasses a 10 x 20 km area of rhyolite welded tuff and granite porphyry ~100 km west of the Yukon border. Intracaldera tuff has ≤4 mm quartz and feldspar phenocrysts and cm-sized fiamme; its maximum exposed thickness is 850 m. Less densely welded tuff near the caldera margins locally contains 1-2 cm K-feldspar megacrysts and pumice clasts to 6 cm. Zircon from intracaldera tuff yields a SHRIMP-RG U-Pb age of 68.7 ± 1.1 Ma (all ages 95% confidence). Granite porphyry occupies much of an 8 x 12 km area having 650 m of relief within the western part of the caldera fill. Zircon from the porphyry gives a SHRIMP-RG U-Pb age of 68.4 ± 1.0 Ma. These ages agree with a previous 40Ar/39Ar biotite age of 69.1 ± 0.5 Ma for proximal outflow tuff. The crystal-rich intracaldera tuff contains embayed quartz, plagioclase>K-feldspar, biotite, and Fe-Ti oxide phenocrysts in a very fine-grained crystalline groundmass. The porphyry carries 40-50% of larger phenocrysts of the same phases (skeletal quartz to 1 cm; K-feldspar to 2 cm, rarely to 4 cm) in a fine-grained groundmass characterized by abundant 50-100 μm quartz. Compositions of 3 tuff and 3 porphyry samples overlap, form a limited differentiation series at 69-72% SiO2, have arc geochemical signatures, and yield subparallel chondrite-normalized rare earth element patterns with light REE enrichment, concave-upward heavy REE, and small negative Eu anomalies. Although their phenocrysts differ in size (owing to fragmentation of crystals in the tuff) and abundance, the similar mineralogy, composition (in spite of crystal concentration in the tuff), and indistinguishable ages of the tuff and porphyry indicate that the magmas were closely related. A rare magmatic enclave (54% SiO2, arc geochemical signature) in the porphyry may be similar to parental magma and provides evidence of mafic magma and thermal input. The porphyry is interpreted

  10. Wireless tuning fork gyroscope for biomedical applications

    NASA Astrophysics Data System (ADS)

    Abraham, Jose K.; Varadan, Vijay K.; Whitchurch, Ashwin K.; Sarukesi, K.

    2003-07-01

    This paper presents the development of a Bluetooth enabled wireless tuning fork gyroscope for the biomedical applications, including gait phase detection system, human motion analysis and physical therapy. This gyroscope is capable of measuring rotation rates between -90 and 90 and it can read the rotation information using a computer. Currently, the information from a gyroscope can trigger automobile airbag deployment during rollover, improve the accuracy and reliability of GPS navigation systems and stabilize moving platforms such as automobiles, airplanes, robots, antennas, and industrial equipment. Adding wireless capability to the existing gyroscope could help to expand its applications in many areas particularly in biomedical applications, where a continuous patient monitoring is quite difficult. This wireless system provides information on several aspects of activities of patients for real-time monitoring in hospitals.

  11. Fork gratings based on ferroelectric liquid crystals.

    PubMed

    Ma, Y; Wei, B Y; Shi, L Y; Srivastava, A K; Chigrinov, V G; Kwok, H-S; Hu, W; Lu, Y Q

    2016-03-21

    In this article, we disclose a fork grating (FG) based on the photo-aligned ferroelectric liquid crystal (FLC). The Digital Micro-mirror Device based system is used as a dynamic photomask to generated different holograms. Because of controlled anchoring energy, the photo alignment process offers optimal conditions for the multi-domain FLC alignment. Two different electro-optical modes namely DIFF/TRANS and DIFF/OFF switchable modes have been proposed where the diffraction can be switched either to no diffraction or to a completely black state, respectively. The FLC FG shows high diffraction efficiency and fast response time of 50µs that is relatively faster than existing technologies. Thus, the FLC FG may pave a good foundation toward optical vertices generation and manipulation that could find applications in a variety of devices. PMID:27136779

  12. Chemical and biological sensing using tuning forks

    DOEpatents

    Tao, Nongjian; Boussaad, Salah

    2012-07-10

    A device for sensing a chemical analyte is disclosed. The device is comprised of a vibrating structure having first and second surfaces and having an associated resonant frequency and a wire coupled between the first and second surfaces of the vibrating structure, wherein the analyte interacts with the wire and causes a change in the resonant frequency of the vibrating structure. The vibrating structure can include a tuning fork. The vibrating structure can be comprised of quartz. The wire can be comprised of polymer. A plurality of vibrating structures are arranged in an array to increase confidence by promoting a redundancy of measurement or to detect a plurality of chemical analytes. A method of making a device for sensing a chemical analyte is also disclosed.

  13. NORTH FORK JOHN DAY RIVER ROADLESS AREA, OREGON.

    USGS Publications Warehouse

    Evans, James G.; Conyac, Martin D.

    1984-01-01

    A mineral survey of the North Fork John Day River Roadless Area in Oregon indicates that a narrow belt along the river has a substantiated resource potential for placer gold, and several other drainages tributary to the North Fork a probable resource potential for placer or lode gold. Further study of the roadless area may reveal other areas with a potential for gold, and could help to delineate bedrock or additional placer resources, especially in drainages tributary to the North Fork. This work could also point to other mineral deposits near the roadless boundary.

  14. 35. CHARGING DOOR OF CUPOLA FORM LOFT, WITH FORKS FOR ...

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

    35. CHARGING DOOR OF CUPOLA FORM LOFT, WITH FORKS FOR FEEDING COKE, FOUNDRY BELOW-LOOKING NORTH. - W. A. Young & Sons Foundry & Machine Shop, On Water Street along Monongahela River, Rices Landing, Greene County, PA

  15. TRAIP regulates replication fork recovery and progression via PCNA

    PubMed Central

    Feng, Wanjuan; Guo, Yingying; Huang, Jun; Deng, Yiqun; Zang, Jianye; Huen, Michael Shing-Yan

    2016-01-01

    PCNA is a central scaffold that coordinately assembles replication and repair machineries at DNA replication forks for faithful genome duplication. Here, we describe TRAIP (RNF206) as a novel PCNA-interacting factor that has important roles during mammalian replicative stress responses. We show that TRAIP encodes a nucleolar protein that migrates to stalled replication forks, and that this is accomplished by its targeting of PCNA via an evolutionarily conserved PIP box on its C terminus. Accordingly, inactivation of TRAIP or its interaction with the PCNA clamp compromised replication fork recovery and progression, and leads to chromosome instability. Together, our findings establish TRAIP as a component of the mammalian replicative stress response network, and implicate the TRAIP-PCNA axis in recovery of stalled replication forks. PMID:27462463

  16. 8. EEL RIVER SOUTH FORK BRIDGE, OLD HIGHWAY 101. NORTH ...

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

    8. EEL RIVER SOUTH FORK BRIDGE, OLD HIGHWAY 101. NORTH OF LEGGETT, HUMBOLDT COUNTY, CALIFORNIA. LOOKING N. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  17. 9. EEL RIVER SOUTH FORK BRIDGE, OLD HIGHWAY 101. NORTH ...

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

    9. EEL RIVER SOUTH FORK BRIDGE, OLD HIGHWAY 101. NORTH OF LEGGETT, HUMBOLDT COUNTY, CALIFORNIA. LOOKING W. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  18. 117. Laurel Fork Viaduct. Elevation view of this 545 1939 ...

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

    117. Laurel Fork Viaduct. Elevation view of this 545 1939 steel girder viaduct. Example of structure with plain reinforced concrete arches. Looking northwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  19. Little Known Facts about the Common Tuning Fork.

    ERIC Educational Resources Information Center

    Ong, P. P.

    2002-01-01

    Explains the physical principles of the tuning fork which has a common use in teaching laboratories. Includes information on its vibration, frequency of vibration, elasticity, and reasons for having two prongs. (YDS)

  20. 17. DETAIL VIEW OF WHAT APPEARS TO BE STIRRING FORK ...

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

    17. DETAIL VIEW OF WHAT APPEARS TO BE STIRRING FORK THAT MIXED COFFEE BEANS AS THEY WERE HUSKED - Hacienda Cafetalera Santa Clara, Coffee Mill, KM 19, PR Route 372, Hacienda La Juanita, Yauco Municipio, PR

  1. HOMESTEAD, LAKE FORK, AND LICK CREEK ROADLESS AREAS, OREGON.

    USGS Publications Warehouse

    Evans, James G.; Conyac, Martin D.

    1984-01-01

    A mineral survey concluded that the Homestead, Lake Fork and Lick Creek Roadless Area, Oregon offer little promise for the occurrence of mineral or energy resources in the bedrock. Probable mineral-resource potential is assigned to the west and north parts of the Lake Fork Roadless Area, where gold resources may occur in glacial deposits and alluvium transported into this area from sources outside the roadless area to the west.

  2. Unwinding of forked DNA structures by UvrD.

    PubMed

    Cadman, Chris J; Matson, Steven W; McGlynn, Peter

    2006-09-01

    Many studies have demonstrated the need for processing of blocked replication forks to underpin genome duplication. UvrD helicase in Escherichia coli has been implicated in the processing of damaged replication forks, or the recombination intermediates formed from damaged forks. Here we show that UvrD can unwind forked DNA structures, in part due to the ability of UvrD to initiate unwinding from discontinuities within the phosphodiester backbone of DNA. UvrD does therefore have the capacity to target DNA intermediates of replication and recombination. Such an activity resulted in unwinding of what would be the parental duplex DNA ahead of either a stalled replication fork or a D-loop formed by recombination. However, UvrD had a substrate preference for fork structures having a nascent lagging strand at the branch point but no leading strand. Furthermore, at such structures the polarity of UvrD altered so that unwinding of the lagging strand predominated. This reaction is reminiscent of the PriC-Rep pathway of replication restart, suggesting that UvrD and Rep may have at least partially redundant functions. PMID:16890954

  3. Non-replicative helicases at the replication fork.

    PubMed

    Heller, Ryan C; Marians, Kenneth J

    2007-07-01

    Reactivation of stalled or collapsed replication forks is an essential process in bacteria. Restart systems operate to restore the 5'-->3' replicative helicase, DnaB, to the lagging-strand template. However, other non-replicative 3'-->5' helicases play an important role in the restart process as well. Here we examine the DNA-binding specificity of three of the latter group, PriA, Rep, and UvrD. Only PriA and Rep display structure-specific fork binding. Interestingly, their specificity is opposite: PriA binds a leading-strand fork, presumably reflecting its restart activity in directing loading of DnaB to the lagging-strand template. Rep binds a lagging-strand fork, presumably reflecting its role in partially displacing Okazaki fragments that originate near the fork junction. This activity is necessary for generating a single-stranded landing pad for DnaB. While UvrD shows little structure-specificity, there is a slight preference for lagging-strand forks, suggesting that there might be some redundancy between Rep and UvrD and possibly explaining the observed synthetic lethality that occurs when mutations in the genes encoding these two proteins are combined. PMID:17382604

  4. Force regulated dynamics of RPA on a DNA fork

    PubMed Central

    Kemmerich, Felix E.; Daldrop, Peter; Pinto, Cosimo; Levikova, Maryna; Cejka, Petr; Seidel, Ralf

    2016-01-01

    Replication protein A (RPA) is a single-stranded DNA binding protein, involved in most aspects of eukaryotic DNA metabolism. Here, we study the behavior of RPA on a DNA substrate that mimics a replication fork. Using magnetic tweezers we show that both yeast and human RPA can open forked DNA when sufficient external tension is applied. In contrast, at low force, RPA becomes rapidly displaced by the rehybridization of the DNA fork. This process appears to be governed by the binding or the release of an RPA microdomain (toehold) of only few base-pairs length. This gives rise to an extremely rapid exchange dynamics of RPA at the fork. Fork rezipping rates reach up to hundreds of base-pairs per second, being orders of magnitude faster than RPA dissociation from ssDNA alone. Additionally, we show that RPA undergoes diffusive motion on ssDNA, such that it can be pushed over long distances by a rezipping fork. Generally the behavior of both human and yeast RPA homologs is very similar. However, in contrast to yeast RPA, the dissociation of human RPA from ssDNA is greatly reduced at low Mg2+ concentrations, such that human RPA can melt DNA in absence of force. PMID:27016742

  5. The Replication Checkpoint Protects Fork Stability by Releasing Transcribed Genes from Nuclear Pores

    PubMed Central

    Bermejo, Rodrigo; Capra, Thelma; Jossen, Rachel; Colosio, Arianna; Frattini, Camilla; Carotenuto, Walter; Cocito, Andrea; Doksani, Ylli; Klein, Hannah; Gómez-González, Belén; Aguilera, Andrés; Katou, Yuki; Shirahige, Katsuhiko; Foiani, Marco

    2011-01-01

    Summary Transcription hinders replication fork progression and stability, and the Mec1/ATR checkpoint protects fork integrity. Examining checkpoint-dependent mechanisms controlling fork stability, we find that fork reversal and dormant origin firing due to checkpoint defects are rescued in checkpoint mutants lacking THO, TREX-2, or inner-basket nucleoporins. Gene gating tethers transcribed genes to the nuclear periphery and is counteracted by checkpoint kinases through phosphorylation of nucleoporins such as Mlp1. Checkpoint mutants fail to detach transcribed genes from nuclear pores, thus generating topological impediments for incoming forks. Releasing this topological complexity by introducing a double-strand break between a fork and a transcribed unit prevents fork collapse. Mlp1 mutants mimicking constitutive checkpoint-dependent phosphorylation also alleviate checkpoint defects. We propose that the checkpoint assists fork progression and stability at transcribed genes by phosphorylating key nucleoporins and counteracting gene gating, thus neutralizing the topological tension generated at nuclear pore gated genes. PMID:21784245

  6. A Multi-Fork Z-Axis Quartz Micromachined Gyroscope

    PubMed Central

    Feng, Lihui; Zhao, Ke; Sun, Yunan; Cui, Jianmin; Cui, Fang; Yang, Aiying

    2013-01-01

    A novel multi-fork z-axis gyroscope is presented in this paper. Different from traditional quartz gyroscopes, the lateral electrodes of the sense beam can be arranged in simple patterns; as a result, the fabrication is simplified. High sensitivity is achieved by the multi-fork design. The working principles are introduced, while the finite element method (FEM) is used to simulate the modal and sensitivity. A quartz fork is fabricated, and a prototype is assembled. Impedance testing shows that the drive frequency and sense frequency are similar to the simulations, and the quality factor is approximately 10,000 in air. The scale factor is measured to be 18.134 mV/(°/s) and the nonlinearity is 0.40% in a full-scale input range of ±250 °/s. PMID:24048339

  7. Bank stability and channel width adjustment, East Fork River, Wyoming.

    USGS Publications Warehouse

    Andrews, E.D.

    1982-01-01

    Frequent surveys of eight cross sections located in self-formed reaches of the East Fork River, Wyoming, during the 1974 snowmelt flood showed a close relation between channel morphology and scour and fill. Those cross sections narrower than the mean reach width filled at discharges less than bankfull and scoured at discharges greater than bankfull. Those cross sections wider than the mean reach width scoured at discharges less than bankfull and filled at discharges greater than bankfull. Bank stability, and to some extent the adjustment of stream channel width, in the East Fork River study reach appears to be controlled by the processes of scour and fill. -from Author

  8. Replication Termination: Containing Fork Fusion-Mediated Pathologies in Escherichia coli

    PubMed Central

    Dimude, Juachi U.; Midgley-Smith, Sarah L.; Stein, Monja; Rudolph, Christian J.

    2016-01-01

    Duplication of bacterial chromosomes is initiated via the assembly of two replication forks at a single defined origin. Forks proceed bi-directionally until they fuse in a specialised termination area opposite the origin. This area is flanked by polar replication fork pause sites that allow forks to enter but not to leave. The precise function of this replication fork trap has remained enigmatic, as no obvious phenotypes have been associated with its inactivation. However, the fork trap becomes a serious problem to cells if the second fork is stalled at an impediment, as replication cannot be completed, suggesting that a significant evolutionary advantage for maintaining this chromosomal arrangement must exist. Recently, we demonstrated that head-on fusion of replication forks can trigger over-replication of the chromosome. This over-replication is normally prevented by a number of proteins including RecG helicase and 3’ exonucleases. However, even in the absence of these proteins it can be safely contained within the replication fork trap, highlighting that multiple systems might be involved in coordinating replication fork fusions. Here, we discuss whether considering the problems associated with head-on replication fork fusion events helps us to better understand the important role of the replication fork trap in cellular metabolism. PMID:27463728

  9. Functional Analysis of DNA Replication Fork Reversal Catalyzed by Mycobacterium tuberculosis RuvAB Proteins*

    PubMed Central

    Khanduja, Jasbeer Singh; Muniyappa, K.

    2012-01-01

    Initially discovered in Escherichia coli, RuvAB proteins are ubiquitous in bacteria and play a dual role as molecular motor proteins responsible for branch migration of the Holliday junction(s) and reversal of stalled replication forks. Despite mounting genetic evidence for a crucial role of RuvA and RuvB proteins in reversal of stalled replication forks, the mechanistic aspects of this process are still not fully understood. Here, we elucidate the ability of Mycobacterium tuberculosis RuvAB (MtRuvAB) complex to catalyze the reversal of replication forks using a range of DNA replication fork substrates. Our studies show that MtRuvAB, unlike E. coli RuvAB, is able to drive replication fork reversal via the formation of Holliday junction intermediates, suggesting that RuvAB-catalyzed fork reversal involves concerted unwinding and annealing of nascent leading and lagging strands. We also demonstrate the reversal of replication forks carrying hemi-replicated DNA, indicating that MtRuvAB complex-catalyzed fork reversal is independent of symmetry at the fork junction. The fork reversal reaction catalyzed by MtRuvAB is coupled to ATP hydrolysis, is processive, and culminates in the formation of an extended reverse DNA arm. Notably, we found that sequence heterology failed to impede the fork reversal activity of MtRuvAB. We discuss the implications of these results in the context of recognition and processing of varied types of replication fork structures by RuvAB proteins. PMID:22094465

  10. 78 FR 13660 - Middle Fork American River Project; Notice of Availability of the Final Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-28

    ... Energy Regulatory Commission Middle Fork American River Project; Notice of Availability of the Final Environmental Impact Statement for the Middle Fork American River Hydrolectric Project In accordance with the... Projects has reviewed the application for license for the Middle Fork American River Hydroelectric...

  11. Replication Termination: Containing Fork Fusion-Mediated Pathologies in Escherichia coli.

    PubMed

    Dimude, Juachi U; Midgley-Smith, Sarah L; Stein, Monja; Rudolph, Christian J

    2016-01-01

    Duplication of bacterial chromosomes is initiated via the assembly of two replication forks at a single defined origin. Forks proceed bi-directionally until they fuse in a specialised termination area opposite the origin. This area is flanked by polar replication fork pause sites that allow forks to enter but not to leave. The precise function of this replication fork trap has remained enigmatic, as no obvious phenotypes have been associated with its inactivation. However, the fork trap becomes a serious problem to cells if the second fork is stalled at an impediment, as replication cannot be completed, suggesting that a significant evolutionary advantage for maintaining this chromosomal arrangement must exist. Recently, we demonstrated that head-on fusion of replication forks can trigger over-replication of the chromosome. This over-replication is normally prevented by a number of proteins including RecG helicase and 3' exonucleases. However, even in the absence of these proteins it can be safely contained within the replication fork trap, highlighting that multiple systems might be involved in coordinating replication fork fusions. Here, we discuss whether considering the problems associated with head-on replication fork fusion events helps us to better understand the important role of the replication fork trap in cellular metabolism. PMID:27463728

  12. 76 FR 35909 - Temporary Concession Contract for Big South Fork National Recreation Area, TN/KY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... contract for Big South Fork National Recreation Area, TN/KY. SUMMARY: Pursuant to 36 CFR 51.24, public... National Park Service Temporary Concession Contract for Big South Fork National Recreation Area, TN/KY... contract for the conduct of certain visitor services within Big South Fork National Recreation...

  13. 80. Laurel Fork Creek Bridge #2. Example of a concrete ...

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

    80. Laurel Fork Creek Bridge #2. Example of a concrete slab bridge with T beams. It was built in 1937 and the wing walls were faced with stone to blend with its surroundings. Looking northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  14. 132. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN ...

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

    132. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN FALLS COUNTY, SOUTH OF HANSEN, IDAHO; POWER GATES FOR HYDRO-ELECTRIC. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

  15. Ten Things You Should Do with a Tuning Fork

    ERIC Educational Resources Information Center

    Lincoln, James

    2013-01-01

    Tuning forks are wonderful tools for teaching physics. Every physics classroom should have several and every physics student should be taught how to use them. In this article, I highlight 10 enriching demonstrations that most teachers might not know, as well as provide tips to enhance the demonstrations teachers might already be doing. Some of…

  16. The Fork in the Road: Histone Partitioning During DNA Replication

    PubMed Central

    Annunziato, Anthony T.

    2015-01-01

    In the following discussion the distribution of histones at the replication fork is examined, with specific attention paid to the question of H3/H4 tetramer "splitting." After a presentation of early experiments surrounding this topic, more recent contributions are detailed. The implications of these findings with respect to the transmission of histone modifications and epigenetic models are also addressed. PMID:26110314

  17. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  18. Aging.

    PubMed

    Park, Dong Choon; Yeo, Seung Geun

    2013-09-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  19. Fork rotation and DNA precatenation are restricted during DNA replication to prevent chromosomal instability

    PubMed Central

    Schalbetter, Stephanie A.; Mansoubi, Sahar; Chambers, Anna L.; Downs, Jessica A.; Baxter, Jonathan

    2015-01-01

    Faithful genome duplication and inheritance require the complete resolution of all intertwines within the parental DNA duplex. This is achieved by topoisomerase action ahead of the replication fork or by fork rotation and subsequent resolution of the DNA precatenation formed. Although fork rotation predominates at replication termination, in vitro studies have suggested that it also occurs frequently during elongation. However, the factors that influence fork rotation and how rotation and precatenation may influence other replication-associated processes are unknown. Here we analyze the causes and consequences of fork rotation in budding yeast. We find that fork rotation and precatenation preferentially occur in contexts that inhibit topoisomerase action ahead of the fork, including stable protein–DNA fragile sites and termination. However, generally, fork rotation and precatenation are actively inhibited by Timeless/Tof1 and Tipin/Csm3. In the absence of Tof1/Timeless, excessive fork rotation and precatenation cause extensive DNA damage following DNA replication. With Tof1, damage related to precatenation is focused on the fragile protein–DNA sites where fork rotation is induced. We conclude that although fork rotation and precatenation facilitate unwinding in hard-to-replicate contexts, they intrinsically disrupt normal chromosome duplication and are therefore restricted by Timeless/Tipin. PMID:26240319

  20. Oak Grove Fork Habitat Improvement Project, 1988 Annual Report.

    SciTech Connect

    Bettin, Scott

    1989-04-01

    The Lower Oak Grove Fork of the Clackamas River is a fifth-order tributary of the Clackamas River drainage supporting depressed runs of coho and chinook salmon, and summer and winter steelhead. Habitat condition rating for the Lower Oak Grove is good, but smelt production estimates are below the average for Clackamas River tributaries. Limiting factors in the 3.8 miles of the Lower Oak Grove supporting anadromous fish include an overall lack of quality spawning and rearing habitat. Beginning in 1986. measures to improve fish habitat in the Lower Oak Grove were developed in coordination with the Oregon Department of Fish and Wildlife (ODF&W) and Portland General Electric (PGE) fisheries biologists. Prior to 1986, no measures had been applied to the stream to mitigate for PGE's storage and regulation of flows in the Oak Grove Fork (Timothy Lake, Harriet Lake). Catchable rainbow trout are stocked by ODF&W two or three times a year during the trout fishing season in the lowermost portion of the Oak Grove Fork near two Forest Service campgrounds (Ripplebrook and Rainbow). The 1987 field season marked the third year of efforts to improve fish habitat of the Lower Oak Grove Fork and restore anadromous fish production. The efforts included the development of an implementation plan for habitat improvement activities in the Lower Oak Grove Fork. post-project monitoring. and maintenance of the 1986 improvement structures. No new structures were constructed or placed in 1987. Fiscal year 1988 brought a multitude of changes which delayed implementation of plans developed in 1987. The most prominent change was the withdrawal of the proposed Spotted Owl Habitat Area (SOHA) which overlapped the Oak Grove project implementation area. Another was the change in the Forest Service biologist responsible for implementation and design of this project.

  1. Termination of DNA replication forks: “Breaking up is hard to do”

    PubMed Central

    Bailey, Rachael; Priego Moreno, Sara; Gambus, Agnieszka

    2015-01-01

    To ensure duplication of the entire genome, eukaryotic DNA replication initiates from thousands of replication origins. The replication forks move through the chromatin until they encounter forks from neighboring origins. During replication fork termination forks converge, the replisomes disassemble and topoisomerase II resolves the daughter DNA molecules. If not resolved efficiently, terminating forks result in genomic instability through the formation of pathogenic structures. Our recent findings shed light onto the mechanism of replisome disassembly upon replication fork termination. We have shown that termination-specific polyubiquitylation of the replicative helicase component – Mcm7, leads to dissolution of the active helicase in a process dependent on the p97/VCP/Cdc48 segregase. The inhibition of terminating helicase disassembly resulted in a replication termination defect. In this extended view we present hypothetical models of replication fork termination and discuss remaining and emerging questions in the DNA replication termination field. PMID:25835602

  2. Mitomycin C reduces abundance of replication forks but not rates of fork progression in primary and transformed human cells

    PubMed Central

    Kehrli, Keffy; Sidorova, Julia M.

    2014-01-01

    DNA crosslinks can block replication in vitro and slow down S phase progression in vivo. We characterized the effect of mitomycin C crosslinker on S phase globally and on individual replication forks in wild type and FANCD2-deficient human cells. FANCD2 is critical to crosslink repair, and is also implicated in facilitating DNA replication. We used DNA fiber analysis to demonstrate persistent reduction in abundance but not progression rate of replication forks during an S phase of MMC-treated cells. FANCD2 deficiency did not eliminate this phenotype. Immunoprecipitation of EdU-labeled DNA indicated that replication was not suppressed in the domains that were undergoing response to MMC as marked by the presence of γH2AX, and in fact γH2AX was overrepresented on DNA that had replicated immediately after MMC in wild type through less so in FANCD2-depleted cells. FANCD2-depleted cells also produced fewer tracks of uninterrupted replication of up to 240Kb long, regardless of MMC treatment. Overall, the data suggest that crosslinks may not pose a block to S phase as a whole, but instead profoundly change its progress by reducing density of replication forks and causing at least a fraction of forks to operate within a DNA damage response-altered chromatin. PMID:25580447

  3. HOWARD FORK ACID ROCK DRAINAGE SOURCE INTERCEPTION STUDY; HOWARD FORK OF THE SAN MIGUEL RIVER NEAR OPHIR, COLORADO

    EPA Science Inventory

    This project proposes to analyze regional hydrogeology as it relates to mine workings which discharge significant heavy metals into the Howard Fork of the San Miguel River and recommend strategies to intercept and divert water away from mineralized zones. The study also includes...

  4. Analysis of fork-join program response times on multiprocessors

    SciTech Connect

    Towsley, D.; Stankovic, J.A. . Dept. of Computer and Information Science); Rommel, C.G. )

    1990-07-01

    In this paper, the authors develop analytic models for a shared memory multiprocessor that executes fork-join parallel programs. Here a fork-join program is one that consists of a set of n {ge} 1 parallel tasks. All of the tasks of a program arrive simultaneously to the system and the job is assumed to complete when the last task completes. They develop and analyze models for two processor sharing policies, called task scheduling processor sharing and job scheduling processor sharing. The first policy schedules tasks independently of each other and allows parallel execution of an individual program, whereas the second policy schedules each job as a unit and thereby does not allow parallel execution of an individual program.

  5. Optimal information provision for maximizing flow in a forked lattice

    NASA Astrophysics Data System (ADS)

    Imai, Takeaki; Nishinari, Katsuhiro

    2015-06-01

    In a forked road, the provision of inappropriate information to car drivers sometimes leads to undesirable situations such as one-sided congestion, which is called the hunting phenomenon in real traffic. To address such problems, we propose a forked exclusion model and investigate the behavior of traffic flow in two routes, providing various types of information to a limited number of traveling particles according to the share rate of information. To analytically understand the phenomena, we develop a coarse-grained representation of the model. By analyzing the model, we find the most effective types of information to minimize particles' travel time and the existence of an optimal share rate according to route conditions.

  6. Ten Things You Should Do with a Tuning Fork

    NASA Astrophysics Data System (ADS)

    Lincoln, James

    2013-03-01

    Tuning forks are wonderful tools for teaching physics. Every physics classroom should have several and every physics student should be taught how to use them. In this article, I highlight 10 enriching demonstrations that most teachers might not know, as well as provide tips to enhance the demonstrations teachers might already be doing. Some of these demonstrations have appeared in literature before, but this paper will serve as a collection of ideas that will be helpful for both the beginner and master teacher.

  7. Stalled replication forks within heterochromatin require ATRX for protection.

    PubMed

    Huh, M S; Ivanochko, D; Hashem, L E; Curtin, M; Delorme, M; Goodall, E; Yan, K; Picketts, D J

    2016-01-01

    Expansive growth of neural progenitor cells (NPCs) is a prerequisite to the temporal waves of neuronal differentiation that generate the six-layered neocortex, while also placing a heavy burden on proteins that regulate chromatin packaging and genome integrity. This problem is further reflected by the growing number of developmental disorders caused by mutations in chromatin regulators. ATRX gene mutations cause a severe intellectual disability disorder (α-thalassemia mental retardation X-linked (ATRX) syndrome; OMIM no. 301040), characterized by microcephaly, urogenital abnormalities and α-thalassemia. Although the ATRX protein is required for the maintenance of repetitive DNA within heterochromatin, how this translates to disease pathogenesis remain poorly understood and was a focus of this study. We demonstrate that Atrx(FoxG1Cre) forebrain-specific conditional knockout mice display poly(ADP-ribose) polymerase-1 (Parp-1) hyperactivation during neurogenesis and generate fewer late-born Cux1- and Brn2-positive neurons that accounts for the reduced cortical size. Moreover, DNA damage, induced Parp-1 and Atm activation is elevated in progenitor cells and contributes to their increased level of cell death. ATRX-null HeLa cells are similarly sensitive to hydroxyurea-induced replication stress, accumulate DNA damage and proliferate poorly. Impaired BRCA1-RAD51 colocalization and PARP-1 hyperactivation indicated that stalled replication forks are not efficiently protected. DNA fiber assays confirmed that MRE11 degradation of stalled replication forks was rampant in the absence of ATRX or DAXX. Indeed, fork degradation in ATRX-null cells could be attenuated by treatment with the MRE11 inhibitor mirin, or exacerbated by inhibiting PARP-1 activity. Taken together, these results suggest that ATRX is required to limit replication stress during cellular proliferation, whereas upregulation of PARP-1 activity functions as a compensatory mechanism to protect stalled forks

  8. South Fork Clearwater River Habitat Enhancement, Nez Perce National Forest.

    SciTech Connect

    Siddall, Phoebe

    1992-04-01

    In 1984, the Nez Perce National forest and the Bonneville Power Administration entered into a contractual agreement which provided for improvement of spring chinook salmon and summer steelhead trout habitat in south Fork Clearwater River tributaries. Project work was completed in seven main locations: Crooked River, Red River, Meadow Creek Haysfork Gloryhole, Cal-Idaho Gloryhole, Fisher Placer and Leggett Placer. This report describes restoration activities at each of these sites.

  9. NORTH FORK OF THE AMERICAN RIVER WILDERNESS STUDY AREA, CALIFORNIA.

    USGS Publications Warehouse

    Harwood, David S.; Federspiel, Francis E.

    1984-01-01

    Mineral-resource surveys of the North Fork of the American River Wilderness study area, California have identified a zone of substantiated resource potential for gold and silver. Zones of probable gold and silver potential occur in the eastern part of the area between the Wubbena and La Trinidad mines and locally around the Marrs mine. A zone with probable chromium potential occurs in the serpentinite belt along the western border of the area. No energy resources were identified in this study.

  10. Stalled replication forks within heterochromatin require ATRX for protection

    PubMed Central

    Huh, M S; Ivanochko, D; Hashem, L E; Curtin, M; Delorme, M; Goodall, E; Yan, K; Picketts, D J

    2016-01-01

    Expansive growth of neural progenitor cells (NPCs) is a prerequisite to the temporal waves of neuronal differentiation that generate the six-layered neocortex, while also placing a heavy burden on proteins that regulate chromatin packaging and genome integrity. This problem is further reflected by the growing number of developmental disorders caused by mutations in chromatin regulators. ATRX gene mutations cause a severe intellectual disability disorder (α-thalassemia mental retardation X-linked (ATRX) syndrome; OMIM no. 301040), characterized by microcephaly, urogenital abnormalities and α-thalassemia. Although the ATRX protein is required for the maintenance of repetitive DNA within heterochromatin, how this translates to disease pathogenesis remain poorly understood and was a focus of this study. We demonstrate that AtrxFoxG1Cre forebrain-specific conditional knockout mice display poly(ADP-ribose) polymerase-1 (Parp-1) hyperactivation during neurogenesis and generate fewer late-born Cux1- and Brn2-positive neurons that accounts for the reduced cortical size. Moreover, DNA damage, induced Parp-1 and Atm activation is elevated in progenitor cells and contributes to their increased level of cell death. ATRX-null HeLa cells are similarly sensitive to hydroxyurea-induced replication stress, accumulate DNA damage and proliferate poorly. Impaired BRCA1-RAD51 colocalization and PARP-1 hyperactivation indicated that stalled replication forks are not efficiently protected. DNA fiber assays confirmed that MRE11 degradation of stalled replication forks was rampant in the absence of ATRX or DAXX. Indeed, fork degradation in ATRX-null cells could be attenuated by treatment with the MRE11 inhibitor mirin, or exacerbated by inhibiting PARP-1 activity. Taken together, these results suggest that ATRX is required to limit replication stress during cellular proliferation, whereas upregulation of PARP-1 activity functions as a compensatory mechanism to protect stalled forks

  11. Mitochondrial transcription termination factor 1 directs polar replication fork pausing

    PubMed Central

    Shi, Yonghong; Posse, Viktor; Zhu, Xuefeng; Hyvärinen, Anne K.; Jacobs, Howard T.; Falkenberg, Maria; Gustafsson, Claes M.

    2016-01-01

    During replication of nuclear ribosomal DNA (rDNA), clashes with the transcription apparatus can cause replication fork collapse and genomic instability. To avoid this problem, a replication fork barrier protein is situated downstream of rDNA, there preventing replication in the direction opposite rDNA transcription. A potential candidate for a similar function in mitochondria is the mitochondrial transcription termination factor 1 (MTERF1, also denoted mTERF), which binds to a sequence just downstream of the ribosomal transcription unit. Previous studies have shown that MTERF1 prevents antisense transcription over the ribosomal RNA genes, a process which we here show to be independent of the transcription elongation factor TEFM. Importantly, we now demonstrate that MTERF1 arrests mitochondrial DNA (mtDNA) replication with distinct polarity. The effect is explained by the ability of MTERF1 to act as a directional contrahelicase, blocking mtDNA unwinding by the mitochondrial helicase TWINKLE. This conclusion is also supported by in vivo evidence that MTERF1 stimulates TWINKLE pausing. We conclude that MTERF1 can direct polar replication fork arrest in mammalian mitochondria. PMID:27112570

  12. Replication fork stability confers chemoresistance in BRCA-deficient cells.

    PubMed

    Ray Chaudhuri, Arnab; Callen, Elsa; Ding, Xia; Gogola, Ewa; Duarte, Alexandra A; Lee, Ji-Eun; Wong, Nancy; Lafarga, Vanessa; Calvo, Jennifer A; Panzarino, Nicholas J; John, Sam; Day, Amanda; Crespo, Anna Vidal; Shen, Binghui; Starnes, Linda M; de Ruiter, Julian R; Daniel, Jeremy A; Konstantinopoulos, Panagiotis A; Cortez, David; Cantor, Sharon B; Fernandez-Capetillo, Oscar; Ge, Kai; Jonkers, Jos; Rottenberg, Sven; Sharan, Shyam K; Nussenzweig, André

    2016-07-21

    Cells deficient in the Brca1 and Brca2 genes have reduced capacity to repair DNA double-strand breaks by homologous recombination and consequently are hypersensitive to DNA-damaging agents, including cisplatin and poly(ADP-ribose) polymerase (PARP) inhibitors. Here we show that loss of the MLL3/4 complex protein, PTIP, protects Brca1/2-deficient cells from DNA damage and rescues the lethality of Brca2-deficient embryonic stem cells. However, PTIP deficiency does not restore homologous recombination activity at double-strand breaks. Instead, its absence inhibits the recruitment of the MRE11 nuclease to stalled replication forks, which in turn protects nascent DNA strands from extensive degradation. More generally, acquisition of PARP inhibitors and cisplatin resistance is associated with replication fork protection in Brca2-deficient tumour cells that do not develop Brca2 reversion mutations. Disruption of multiple proteins, including PARP1 and CHD4, leads to the same end point of replication fork protection, highlighting the complexities by which tumour cells evade chemotherapeutic interventions and acquire drug resistance. PMID:27443740

  13. Updated glacial chronology of the South Fork Hoh River valley, Olympic Peninsula, Washington through detailed stratigraphy and OSL dating

    NASA Astrophysics Data System (ADS)

    Wyshnytzky, C.; Rittenour, T. M.; Thackray, G. D.

    2012-12-01

    The Olympic Peninsula lies within a maritime climatic zone under the direct influence of westerly atmospheric flow and Pacific Ocean sea surface temperature variations (i.e. ENSO and PDO). During the last glaciation, large valley glaciers extended radially from the Mt. Olympus area and carved deep valleys, which preserve glacial diamicton, outwash, and lacustrine sediment emplaced during ice advance and retreat. Previous work by Thackray (1996) mapped glacial deposits through several key drainages in the western Olympic Mountains and used exposures along the South Fork Hoh River to reconstruct MIS 2 glaciation and determine the relative extent of the LGM ice margin in the region. Findings suggest that the extent of mountain glaciers in the western Olympics were much reduced during MIS 2 in comparison to MIS 3/4, with glacier mass balance primarily controlled by moisture delivery. Here we discuss new data constraining the style and timing of deglaciation in the South Fork Hoh River valley of the western Olympic Mountains, Washington, USA. Previous research in the South Fork Hoh River used radiocarbon ages, geomorphic mapping, and general stratigraphic relationships to establish a chronostratigraphic framework (Thackray, 1996). To further that understanding and provide new insight on the style and timing of MIS 2 glaciation, we examine the sedimentology and stratigraphic architecture of glacial landforms, which contain invaluable information about glacial processes and style. Optically stimulated luminescence (OSL) dating, commonly regarded as problematic in glacial sediments, constrains the ages of proximal glacial outwash and glaciolacustrine deposits that were traditionally difficult to date due to the lack of organic matter for radiocarbon dating. OSL ages are internally coherent and stratigraphically consistent with previous radiocarbon ages. Results from this research in the South Fork Hoh River valley and associated work in the Queets River valley, the next

  14. Recovery of arrested replication forks by homologous recombination is error-prone.

    PubMed

    Iraqui, Ismail; Chekkal, Yasmina; Jmari, Nada; Pietrobon, Violena; Fréon, Karine; Costes, Audrey; Lambert, Sarah A E

    2012-01-01

    Homologous recombination is a universal mechanism that allows repair of DNA and provides support for DNA replication. Homologous recombination is therefore a major pathway that suppresses non-homology-mediated genome instability. Here, we report that recovery of impeded replication forks by homologous recombination is error-prone. Using a fork-arrest-based assay in fission yeast, we demonstrate that a single collapsed fork can cause mutations and large-scale genomic changes, including deletions and translocations. Fork-arrest-induced gross chromosomal rearrangements are mediated by inappropriate ectopic recombination events at the site of collapsed forks. Inverted repeats near the site of fork collapse stimulate large-scale genomic changes up to 1,500 times over spontaneous events. We also show that the high accuracy of DNA replication during S-phase is impaired by impediments to fork progression, since fork-arrest-induced mutation is due to erroneous DNA synthesis during recovery of replication forks. The mutations caused are small insertions/duplications between short tandem repeats (micro-homology) indicative of replication slippage. Our data establish that collapsed forks, but not stalled forks, recovered by homologous recombination are prone to replication slippage. The inaccuracy of DNA synthesis does not rely on PCNA ubiquitination or trans-lesion-synthesis DNA polymerases, and it is not counteracted by mismatch repair. We propose that deletions/insertions, mediated by micro-homology, leading to copy number variations during replication stress may arise by progression of error-prone replication forks restarted by homologous recombination. PMID:23093942

  15. THE FORK AND THE KINASE: A DNA REPLICATION TALE FROM A CHK1 PERSPECTIVE

    PubMed Central

    González Besteiro, Marina A.; Gottifredi, Vanesa

    2014-01-01

    Replication fork progression is being continuously hampered by exogenously introduced and naturally occurring DNA lesions and other physical obstacles. The checkpoint kinase 1 (Chk1) is activated at replication forks that encounter damaged-DNA. Chk1 inhibits the initiation of new replication factories and stimulates the firing of dormant origins (those in the vicinity of stalled forks). Chk1 also avoids fork collapse into DSBs (double strand breaks) and promotes fork elongation. At the molecular level, the current model considers stalled forks as the site of Chk1 activation and the nucleoplasm as the location where Chk1 phosphorylates target proteins. This model certainly serves to explain how Chk1 modulates origin firing, but how Chk1 controls the fate of stalled forks is less clear. Interestingly, recent reports demonstrating that Chk1 phosphorylates chromatin-bound proteins and even holds kinase-independent functions might shed light on how Chk1 contributes to the elongation of damaged DNA. Such findings unveil a puzzling connection between Chk1 and DNA-lesion bypass, which might be central to promoting fork elongation and checkpoint attenuation. In summary, the multifaceted and versatile functions of Chk1 at ongoing forks and replication origins determine the extent and quality of the cellular response to replication stress. PMID:25795119

  16. Regression of Replication Forks Stalled by Leading-strand Template Damage

    PubMed Central

    Gupta, Sankalp; Yeeles, Joseph T. P.; Marians, Kenneth J.

    2014-01-01

    The orderly progression of replication forks formed at the origin of replication in Escherichia coli is challenged by encounters with template damage, slow moving RNA polymerases, and frozen DNA-protein complexes that stall the fork. These stalled forks are foci for genomic instability and must be reactivated. Many models of replication fork reactivation invoke nascent strand regression as an intermediate in the processing of the stalled fork. We have investigated the replication fork regression activity of RecG and RuvAB, two proteins commonly thought to be involved in the process, using a reconstituted DNA replication system where the replisome is stalled by collision with leading-strand template damage. We find that both RecG and RuvAB can regress the stalled fork in the presence of the replisome and SSB; however, RuvAB generates a completely unwound product consisting of the paired nascent leading and lagging strands, whereas RuvC cleaves the Holliday junction generated by RecG-catalyzed fork regression. We also find that RecG stimulates RuvAB-catalyzed regression, presumably because it is more efficient at generating the initial Holliday junction from the stalled fork. PMID:25138216

  17. Rad51-mediated replication fork reversal is a global response to genotoxic treatments in human cells

    PubMed Central

    Zellweger, Ralph; Dalcher, Damian; Mutreja, Karun; Berti, Matteo; Schmid, Jonas A.; Herrador, Raquel; Vindigni, Alessandro

    2015-01-01

    Replication fork reversal protects forks from breakage after poisoning of Topoisomerase 1. We here investigated fork progression and chromosomal breakage in human cells in response to a panel of sublethal genotoxic treatments, using other topoisomerase poisons, DNA synthesis inhibitors, interstrand cross-linking inducers, and base-damaging agents. We used electron microscopy to visualize fork architecture under these conditions and analyzed the association of specific molecular features with checkpoint activation. Our data identify replication fork uncoupling and reversal as global responses to genotoxic treatments. Both events are frequent even after mild treatments that do not affect fork integrity, nor activate checkpoints. Fork reversal was found to be dependent on the central homologous recombination factor RAD51, which is consistently present at replication forks independently of their breakage, and to be antagonized by poly (ADP-ribose) polymerase/RECQ1-regulated restart. Our work establishes remodeling of uncoupled forks as a pivotal RAD51-regulated response to genotoxic stress in human cells and as a promising target to potentiate cancer chemotherapy. PMID:25733714

  18. Rad51-mediated replication fork reversal is a global response to genotoxic treatments in human cells.

    PubMed

    Zellweger, Ralph; Dalcher, Damian; Mutreja, Karun; Berti, Matteo; Schmid, Jonas A; Herrador, Raquel; Vindigni, Alessandro; Lopes, Massimo

    2015-03-01

    Replication fork reversal protects forks from breakage after poisoning of Topoisomerase 1. We here investigated fork progression and chromosomal breakage in human cells in response to a panel of sublethal genotoxic treatments, using other topoisomerase poisons, DNA synthesis inhibitors, interstrand cross-linking inducers, and base-damaging agents. We used electron microscopy to visualize fork architecture under these conditions and analyzed the association of specific molecular features with checkpoint activation. Our data identify replication fork uncoupling and reversal as global responses to genotoxic treatments. Both events are frequent even after mild treatments that do not affect fork integrity, nor activate checkpoints. Fork reversal was found to be dependent on the central homologous recombination factor RAD51, which is consistently present at replication forks independently of their breakage, and to be antagonized by poly (ADP-ribose) polymerase/RECQ1-regulated restart. Our work establishes remodeling of uncoupled forks as a pivotal RAD51-regulated response to genotoxic stress in human cells and as a promising target to potentiate cancer chemotherapy. PMID:25733714

  19. Mammalian RAD51 paralogs protect nascent DNA at stalled forks and mediate replication restart

    PubMed Central

    Somyajit, Kumar; Saxena, Sneha; Babu, Sharath; Mishra, Anup; Nagaraju, Ganesh

    2015-01-01

    Mammalian RAD51 paralogs are implicated in the repair of collapsed replication forks by homologous recombination. However, their physiological roles in replication fork maintenance prior to fork collapse remain obscure. Here, we report on the role of RAD51 paralogs in short-term replicative stress devoid of DSBs. We show that RAD51 paralogs localize to nascent DNA and common fragile sites upon replication fork stalling. Strikingly, RAD51 paralogs deficient cells exhibit elevated levels of 53BP1 nuclear bodies and increased DSB formation, the latter being attributed to extensive degradation of nascent DNA at stalled forks. RAD51C and XRCC3 promote the restart of stalled replication in an ATP hydrolysis dependent manner by disengaging RAD51 and other RAD51 paralogs from the halted forks. Notably, we find that Fanconi anemia (FA)-like disorder and breast and ovarian cancer patient derived mutations of RAD51C fails to protect replication fork, exhibit under-replicated genomic regions and elevated micro-nucleation. Taken together, RAD51 paralogs prevent degradation of stalled forks and promote the restart of halted replication to avoid replication fork collapse, thereby maintaining genomic integrity and suppressing tumorigenesis. PMID:26354865

  20. BRCA1 controls homologous recombination at Tus/Ter-stalled mammalian replication forks.

    PubMed

    Willis, Nicholas A; Chandramouly, Gurushankar; Huang, Bin; Kwok, Amy; Follonier, Cindy; Deng, Chuxia; Scully, Ralph

    2014-06-26

    Replication fork stalling can promote genomic instability, predisposing to cancer and other diseases. Stalled replication forks may be processed by sister chromatid recombination (SCR), generating error-free or error-prone homologous recombination (HR) outcomes. In mammalian cells, a long-standing hypothesis proposes that the major hereditary breast/ovarian cancer predisposition gene products, BRCA1 and BRCA2, control HR/SCR at stalled replication forks. Although BRCA1 and BRCA2 affect replication fork processing, direct evidence that BRCA gene products regulate homologous recombination at stalled chromosomal replication forks is lacking, due to a dearth of tools for studying this process. Here we report that the Escherichia coli Tus/Ter complex can be engineered to induce site-specific replication fork stalling and chromosomal HR/SCR in mouse cells. Tus/Ter-induced homologous recombination entails processing of bidirectionally arrested forks. We find that the Brca1 carboxy (C)-terminal tandem BRCT repeat and regions of Brca1 encoded by exon 11-two Brca1 elements implicated in tumour suppression-control Tus/Ter-induced homologous recombination. Inactivation of either Brca1 or Brca2 increases the absolute frequency of 'long-tract' gene conversions at Tus/Ter-stalled forks, an outcome not observed in response to a site-specific endonuclease-mediated chromosomal double-strand break. Therefore, homologous recombination at stalled forks is regulated differently from homologous recombination at double-strand breaks arising independently of a replication fork. We propose that aberrant long-tract homologous recombination at stalled replication forks contributes to genomic instability and breast/ovarian cancer predisposition in BRCA mutant cells. PMID:24776801

  1. Interaction force microscopy based on quartz tuning fork force sensor

    NASA Astrophysics Data System (ADS)

    Qin, Yexian

    The ability to sense small changes in the interaction force between a scanning probe microscope (SPM) tip and a substrate requires cantilevers with a sharp mechanical resonance. A typical commercially available cantilever in air is characterized by a resonance with a Q factor of 100 ˜ 300. The low Q factor can be attributed to imperfections in the cantilever itself as well as damping effects of the surrounding air. To substantially increase the Q factor, novel concepts are required. For this reason, we have performed a systematic study of quartz tuning fork resonators for possible use with SPMs. We find that tuning fork resonators operating in air are characterized by Q factors in the order of 104, thereby greatly improving the SPM's ability to measure small shifts in the interaction force. By carefully attaching commercially available SPM tips to the tuning fork, it is possible to obtain SPM images using non-contact imaging techniques and analyze the tip-sample interactions. The assembly of uniform molecular monolayers on atomically flat substrates for molecular electronics applications has received widespread attention during the past ten years. Scanning probe techniques are often used to assess substrate topography, molecular ordering and electronic properties, yet little is known about the fundamental tip-molecule interaction. To address this issue we have built an Interaction Force Microscope using a quartz tuning fork to probe tip-molecular monolayer interactions using scanning probe microscopy. The high quality factor and stable resonant frequency of a quartz tuning fork allows accurate measurement of small shifts in the resonant frequency as the tip interacts with the substrate. To permit an accurate measure of surface interaction forces, the electrical and piezomechanical properties of a tuning fork have been calibrated using a fiber optical interferometer. In prior work [1], we have studied molecular layers formed from either 4-Trifluoro

  2. BLACK FORK MOUNTAIN ROADLESS AREA, ARAKANSAS AND OKLAHOMA.

    USGS Publications Warehouse

    Miller, Mary H.

    1984-01-01

    Black Fork Mountain Roadless Area covers about 21 sq mi in the Ouachita National Forest in Polk County, Arkansas and LeFlore County, Oklahoma. On the basis of a mineral survey the area has little promise for the occurrence of metallic mineral resources. Stone and sand and gravel suitable for construction purposes occur in the Jackfork Sandstone and the Stanley Shale which also occur outside the roadless area. Although the potential for gas and oil is unknown and no resource potential was identified, some investigators believe that there is a possibility for the occurrence of gas and oil in the roadless area.

  3. Glue-free tuning fork shear-force microscope

    NASA Astrophysics Data System (ADS)

    Mühlschlegel, P.; Toquant, J.; Pohl, D. W.; Hecht, B.

    2006-01-01

    A scanning near-field optical microscope without any glued parts is described. Key elements are the optical fiber probe/tuning fork junction and the piezotube scanner assembly. In both cases, fixation is achieved by means of controlled pressure and elastic deformation. The avoidance of glued connections was found to improve the Q factor of the shear-force sensor as well as to facilitate the replacement of the fiber probe and other parts of the scanner head. We present approach curves and shear-force images that demonstrate the performance and stability of the system.

  4. Mutual interactions of oscillating quartz tuning forks in superfluid 4He

    NASA Astrophysics Data System (ADS)

    Sheshin, G.; Gritsenko, I.; Schmoranzer, D.; Skrbek, L.

    2013-10-01

    The quartz tuning fork has recently become a popular experimental tool for investigations of both classical and quantum turbulence in cryogenic helium. Its increased use in low-temperature experiments and a number of puzzling results obtained in the past have led to many questions concerning the interaction of multiple tuning forks or the interaction of tuning forks with other oscillators. We report measurements performed in He II at low temperatures around 360 mK, on the mutual interaction of tuning forks placed in the same volume of fluid, and examine the responsible mechanisms in an effort to discriminate between acoustic coupling and interaction via quantized vortices. To this end, the interaction of two tuning forks is investigated by analyzing their recorded resonance curves, looking for any nonelectrical crosstalk. Further, the force-velocity characteristics of a detector tuning fork are measured for different operating velocities of a generator tuning fork. As a complementary measurement, the intensity of sound waves is recorded using a set of miniature receivers. We confirm the current knowledge on acoustic emission by tuning forks in He II and verify properties of their radiation patterns. We conclude that in our experiment the interaction is almost entirely mediated by sound waves.

  5. 16 CFR Figure 1 to Part 1512 - Bicycle Front Fork Cantilever Bending Test Rig

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Bicycle Front Fork Cantilever Bending Test Rig 1 Figure 1 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... Fork Cantilever Bending Test Rig EC03OC91.070...

  6. 16 CFR Figure 1 to Part 1512 - Bicycle Front Fork Cantilever Bending Test Rig

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Bicycle Front Fork Cantilever Bending Test Rig 1 Figure 1 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... Fork Cantilever Bending Test Rig EC03OC91.070...

  7. 16 CFR Figure 1 to Part 1512 - Bicycle Front Fork Cantilever Bending Test Rig

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Bicycle Front Fork Cantilever Bending Test Rig 1 Figure 1 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... Fork Cantilever Bending Test Rig EC03OC91.070...

  8. 16 CFR Figure 1 to Part 1512 - Bicycle Front Fork Cantilever Bending Test Rig

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Bicycle Front Fork Cantilever Bending Test Rig 1 Figure 1 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... Fork Cantilever Bending Test Rig EC03OC91.070...

  9. 16 CFR Figure 1 to Part 1512 - Bicycle Front Fork Cantilever Bending Test Rig

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Bicycle Front Fork Cantilever Bending Test Rig 1 Figure 1 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... Fork Cantilever Bending Test Rig EC03OC91.070...

  10. 77 FR 45597 - Middle Fork American River Project; Notice of Availability of the Draft Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ... Energy Regulatory Commission Middle Fork American River Project; Notice of Availability of the Draft Environmental Impact Statement for the Middle Fork American River Hydrolectric Project and Intention To Hold... CFR part 380 ), the Office of Energy Projects has reviewed the application for license for the...

  11. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE FLOOD CONTROL REGULATIONS § 208.26 Altus Dam and Reservoir, North Fork Red River, Okla. The Bureau...

  12. 33 CFR 208.33 - Cheney Dam and Reservoir, North Fork of Ninnescah River, Kans.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Cheney Dam and Reservoir, North Fork of Ninnescah River, Kans. 208.33 Section 208.33 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE FLOOD CONTROL REGULATIONS § 208.33 Cheney Dam and Reservoir, North Fork of Ninnescah River,...

  13. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE FLOOD CONTROL REGULATIONS § 208.26 Altus Dam and Reservoir, North Fork Red River, Okla. The Bureau...

  14. 33 CFR 208.33 - Cheney Dam and Reservoir, North Fork of Ninnescah River, Kans.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Cheney Dam and Reservoir, North Fork of Ninnescah River, Kans. 208.33 Section 208.33 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE FLOOD CONTROL REGULATIONS § 208.33 Cheney Dam and Reservoir, North Fork of Ninnescah River,...

  15. 16 CFR 1512.14 - Requirements for fork and frame assembly.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Requirements for fork and frame assembly. 1512.14 Section 1512.14 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... assembly. The fork and frame assembly shall be tested for strength by application of a load of 890 N...

  16. Replication fork movement and methylation govern SeqA binding to the Escherichia coli chromosome

    PubMed Central

    Waldminghaus, Torsten; Weigel, Christoph; Skarstad, Kirsten

    2012-01-01

    In Escherichia coli, the SeqA protein binds specifically to GATC sequences which are methylated on the A of the old strand but not on the new strand. Such hemimethylated DNA is produced by progression of the replication forks and lasts until Dam methyltransferase methylates the new strand. It is therefore believed that a region of hemimethylated DNA covered by SeqA follows the replication fork. We show that this is, indeed, the case by using global ChIP on Chip analysis of SeqA in cells synchronized regarding DNA replication. To assess hemimethylation, we developed the first genome-wide method for methylation analysis in bacteria. Since loss of the SeqA protein affects growth rate only during rapid growth when cells contain multiple replication forks, a comparison of rapid and slow growth was performed. In cells with six replication forks per chromosome, the two old forks were found to bind surprisingly little SeqA protein. Cell cycle analysis showed that loss of SeqA from the old forks did not occur at initiation of the new forks, but instead occurs at a time point coinciding with the end of SeqA-dependent origin sequestration. The finding suggests simultaneous origin de-sequestration and loss of SeqA from old replication forks. PMID:22373925

  17. 77 FR 39675 - Wallowa-Whitman National Forest, Baker County, OR; North Fork Burnt River Mining

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ... River Mining AGENCY: Forest Service, USDA. ACTION: Correction--Notice of intent to prepare a supplement... changed to the Whitman District Ranger. This 2012 North Fork Burnt River Mining Record of Decision will replace and supercede the 2004 North Fork Burnt River Mining Record of Decision only where necessary...

  18. 76 FR 6114 - Lincoln National Forest, New Mexico, North Fork Eagle Creek Wells Special Use Authorization

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... North Fork well field (Village of Ruidoso 2006). The Village of Ruidoso drilled four production wells on... National Forest System land; and (2) Minimizing impacts of groundwater drawdown from this well field to... approximately 31 percent of its water supply from the North Fork well field. During drought conditions prior...

  19. Origin & Evolution of the Grand Forks Human Nutrition Research Center, 1970-90

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the early 1960s William E Cornatzer, MD, PhD, suggested the need for increased USDA research concerning human nutrition, and creation of the Grand Forks Human Nutrition Laboratory (Grand Forks Human Nutrition Research Center). He shared ideas with Senator Milton R. Young of North Dakota, who requ...

  20. First report of anther smut caused by Microbotryum violaceum on forked catchfly in Turkey

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forked catchfly (Silene dichotoma Ehrh.), family Caryophyllaceae, is a common and native plant in rangelands and pastures in Turkey. It is also an introduced plant that is widely distributed in North America. In May, 2007 about 20 forked catchfly plants on the campus of Ondokuz Mayis University, i...

  1. 76 FR 62038 - Boundary Establishment for North Fork Crooked National Wild and Scenic River, Ochoco National...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-06

    ... Forest Service Boundary Establishment for North Fork Crooked National Wild and Scenic River, Ochoco National Forest, Crook County, Oregon AGENCY: Forest Service, USDA. ACTION: Notice of availability. SUMMARY..., Washington Office, is transmitting the final boundary of the North Fork Crooked National Wild and...

  2. EVALUATING THE EFFECTIVENESS OF NUTRIENT MANAGEMENT IN THE CLARK FORK-PEND OREILLE WATERSHED

    EPA Science Inventory

    (1) Analyze the nutrient concentration and algal standing crop trend in the Clark Fork River portion of the watershed; (2) Provide a web-based data access system for reporting Clark Fork River monitoring information; and (3) Evaluate the effectiveness of current nutrient reductio...

  3. Active Control of Repetitive Structural Transitions between Replication Forks and Holliday Junctions by Werner Syndrome Helicase.

    PubMed

    Shin, Soochul; Lee, Jinwoo; Yoo, Sangwoon; Kulikowicz, Tomasz; Bohr, Vilhelm A; Ahn, Byungchan; Hohng, Sungchul

    2016-08-01

    The reactivation of stalled DNA replication via fork regression invokes Holliday junction formation, branch migration, and the recovery of the replication fork after DNA repair or error-free DNA synthesis. The coordination mechanism for these DNA structural transitions by molecular motors, however, remains unclear. Here we perform single-molecule fluorescence experiments with Werner syndrome protein (WRN) and model replication forks. The Holliday junction is readily formed once the lagging arm is unwound, and migrated unidirectionally with 3.2 ± 0.03 bases/s velocity. The recovery of the replication fork was controlled by branch migration reversal of WRN, resulting in repetitive fork regression. The Holliday junction formation, branch migration, and migration direction reversal are all ATP dependent, revealing that WRN uses the energy of ATP hydrolysis to actively coordinate the structural transitions of DNA. PMID:27427477

  4. 76 FR 35009 - Draft Oil and Gas Management Plan/Environmental Impact Statement for Big South Fork National...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-15

    ... National Park Service Draft Oil and Gas Management Plan/Environmental Impact Statement for Big South Fork... Big South Fork National River and Recreation Area and Obed Wild and Scenic River. SUMMARY: Pursuant to.../DEIS) for the proposed Big South Fork National River and Recreation Area (BISO) and Obed Wild...

  5. Grand Forks - East Grand Forks Urban Water Resources Study. Energy conservation and recreation appendix, public involvement appendix. Final report

    SciTech Connect

    Not Available

    1981-07-01

    The goal of the Corps of Engineers Urban Study Program is to provide planning assistance to local interests in a variety of water resource areas. The St. Paul District conducted the Grand Forks-East Grand Forks (GF/EGF) Urban Water Resources Study which was a cooperative effort among local, state and federal agencies. Primary attention was given to flood control, water supply and wastewater management; supporting investigations addressed recreation and energy conservation. The recreation investigation consists of the leisure time analysis conducted in stage 2 of the urban study by the Heritage Conservation and Recreation Service, Department of the Interior. The leisure time analysis compared the study area's recreational needs to the available and planned facilities and identified unsatisfied needs. The thermography investigation was conducted in spring 1978 in response to the public's growing awareness of energy conservation and the Corps' desire to make the public aware of the urban study in a meaningful, useful fashion. The investigation consisted of aerial infrared photography, public displays of photographs, and distribution of information on energy saving practices. This investigation was a one-time effort with no plans for follow-up.

  6. Safeguarding genome stability: RASSF1A tumor suppressor regulates BRCA2 at stalled forks

    PubMed Central

    Pefani, Dafni Eleftheria; O'Neill, Eric

    2015-01-01

    While it has been widely established that defective fork restart after exposure to stress results in increased genomic instability, the importance of fork protection during stalling for safeguarding genomic integrity has recently been fully appreciated. BRCA2, Breast tumor suppressor, has dual functionality promoting not only DNA repair but also preventing DNA lesions at stalled forks. In response to replication stress, BRCA2 recruits RAD51 onto nascent DNA at stalled forks, protecting nascent DNA from nucleolitic cleavage. Phosphorylation of the BRCA2 C-terminal RAD51 binding site by CDK2 promotes RAD51 filament disassembly, leading to nucleolitic cleavage of newly synthesized DNA and compromised fork integrity. Recently we uncovered how the core Hippo pathway components RASSF1A, MST2 and LATS1 regulate CDK2 activity towards BRCA2, in response to fork stalling. In complex with LATS1, CDK2 exhibits reduced kinase activity which results in low levels of pBRCA2-S3291 and stable RAD51 filaments protecting nascent DNA from MRE11 cleavage. In the absence of the RASSF1A/MST2/LATS1/CDK2 pathway increased resection of newly synthesized DNA leads to chromosomal instability and malignant transformation. This function of RASSF1A in stalled replication fork protection adds to the role of RASSF1A as a tumor suppressor and builds up evidence for RASSF1A status and its prognostic and predictive value in cancer. PMID:25927241

  7. Geomorphic Characterization of the Middle Fork Saline River: Garland, Perry, and Saline Counties, Arkansas

    USGS Publications Warehouse

    Pugh, Aaron L.; Garday, Thomas J.; Redman, Ronald

    2008-01-01

    This report was prepared to help address concerns raised by local residents, State, and Federal agencies about the current geomorphic conditions of the Middle Fork Saline River. Over the past 30 years the Middle Fork Saline River Basin has experienced a marked increase in urbanization. The report summarizes the Middle Fork?s current (2003) channel characteristics at nine stream reaches in the upper 91 square miles of the basin. Assessments at each study reach included comparing measured stream geometry dimensions (cross-sectional area, top width, and mean depth) at bankfull stage to regional hydraulic geometry curves for the Ouachita Mountains Physiographic Province of Arkansas and Oklahoma, evaluations of streambed materials and sinuosity, and classification of individual stream reach types. When compared to the Ouachita Mountains? regional hydraulic geometry curves for natural, stable, stream reaches, five of the nine study reaches had slightly smaller crosssectional areas, longer top widths, and shallower depths. Streambed material analysis indicates that the Middle Fork is a bedrock influenced, gravel dominated stream with lesser amounts of sand and cobbles. Slight increases in sinuosity from 1992 to 2002 at seven of the nine study reaches indicate a slight decrease in stream channel slope. Analyses of the Middle Fork?s hydraulic geometry and sinuosity indicate that the Middle Fork is currently overly wide and shallow, but is slowly adjusting towards a deeper, narrower hydraulic geometry. Using the Rosgen system of channel classification, the two upstream study reaches classified as B4c/1 stream types; which were moderately entrenched, riffle dominated channels, with infrequently spaced pools. The downstream seven study reaches classified as C4/1 stream types; which were slightly entrenched, meandering, gravel-dominated, riffle/ pool channels with well developed flood plains. Analyses of stream reach types suggest that the downstream reaches of the Middle Fork

  8. Improved Tuning Fork for Terahertz Quartz-Enhanced Photoacoustic Spectroscopy

    PubMed Central

    Sampaolo, Angelo; Patimisco, Pietro; Giglio, Marilena; Vitiello, Miriam S.; Beere, Harvey E.; Ritchie, David A.; Scamarcio, Gaetano; Tittel, Frank K.; Spagnolo, Vincenzo

    2016-01-01

    We report on a quartz-enhanced photoacoustic (QEPAS) sensor for methanol (CH3OH) detection employing a novel quartz tuning fork (QTF), specifically designed to enhance the QEPAS sensing performance in the terahertz (THz) spectral range. A discussion of the QTF properties in terms of resonance frequency, quality factor and acousto-electric transduction efficiency as a function of prong sizes and spacing between the QTF prongs is presented. The QTF was employed in a QEPAS sensor system using a 3.93 THz quantum cascade laser as the excitation source in resonance with a CH3OH rotational absorption line located at 131.054 cm−1. A minimum detection limit of 160 ppb in 30 s integration time, corresponding to a normalized noise equivalent absorption NNEA = 3.75 × 10−11 cm−1W/Hz½, was achieved, representing a nearly one-order-of-magnitude improvement with respect to previous reports. PMID:27023552

  9. Improved Tuning Fork for Terahertz Quartz-Enhanced Photoacoustic Spectroscopy.

    PubMed

    Sampaolo, Angelo; Patimisco, Pietro; Giglio, Marilena; Vitiello, Miriam S; Beere, Harvey E; Ritchie, David A; Scamarcio, Gaetano; Tittel, Frank K; Spagnolo, Vincenzo

    2016-01-01

    We report on a quartz-enhanced photoacoustic (QEPAS) sensor for methanol (CH₃OH) detection employing a novel quartz tuning fork (QTF), specifically designed to enhance the QEPAS sensing performance in the terahertz (THz) spectral range. A discussion of the QTF properties in terms of resonance frequency, quality factor and acousto-electric transduction efficiency as a function of prong sizes and spacing between the QTF prongs is presented. The QTF was employed in a QEPAS sensor system using a 3.93 THz quantum cascade laser as the excitation source in resonance with a CH₃OH rotational absorption line located at 131.054 cm(-1). A minimum detection limit of 160 ppb in 30 s integration time, corresponding to a normalized noise equivalent absorption NNEA = 3.75 × 10(-11) cm(-1)W/Hz(½), was achieved, representing a nearly one-order-of-magnitude improvement with respect to previous reports. PMID:27023552

  10. Mechanism of asymmetric polymerase assembly at the eukaryotic replication fork.

    PubMed

    Georgescu, Roxana E; Langston, Lance; Yao, Nina Y; Yurieva, Olga; Zhang, Dan; Finkelstein, Jeff; Agarwal, Tani; O'Donnell, Mike E

    2014-08-01

    Eukaryotes use distinct polymerases for leading- and lagging-strand replication, but how they target their respective strands is uncertain. We reconstituted Saccharomyces cerevisiae replication forks and found that CMG helicase selects polymerase (Pol) ɛ to the exclusion of Pol δ on the leading strand. Even if Pol δ assembles on the leading strand, Pol ɛ rapidly replaces it. Pol δ-PCNA is distributive with CMG, in contrast to its high stability on primed ssDNA. Hence CMG will not stabilize Pol δ, instead leaving the leading strand accessible for Pol ɛ and stabilizing Pol ɛ. Comparison of Pol ɛ and Pol δ on a lagging-strand model DNA reveals the opposite. Pol δ dominates over excess Pol ɛ on PCNA-primed ssDNA. Thus, PCNA strongly favors Pol δ over Pol ɛ on the lagging strand, but CMG over-rides and flips this balance in favor of Pol ɛ on the leading strand. PMID:24997598

  11. Mechanism of asymmetric polymerase assembly at the eukaryotic replication fork

    PubMed Central

    Georgescu, Roxana E; Langston, Lance; Yao, Nina Y; Yurieva, Olga; Zhang, Dan; Finkelstein, Jeff; Agarwal, Tani; O’Donnell, Mike E

    2015-01-01

    Eukaryotes use distinct polymerases for leading- and lagging-strand replication, but how they target their respective strands is uncertain. We reconstituted Saccharomyces cerevisiae replication forks and found that CMG helicase selects polymerase (Pol) ε to the exclusion of Pol δ on the leading strand. Even if Pol δ assembles on the leading strand, Pol ε rapidly replaces it. Pol δ–PCNA is distributive with CMG, in contrast to its high stability on primed ssDNA. Hence CMG will not stabilize Pol δ, instead leaving the leading strand accessible for Pol ε and stabilizing Pol ε. Comparison of Pol ε and Pol δ on a lagging-strand model DNA reveals the opposite. Pol δ dominates over excess Pol ε on PCNA-primed ssDNA. Thus, PCNA strongly favors Pol δ over Pol ε on the lagging strand, but CMG over-rides and flips this balance in favor of Pol ε on the leading strand. PMID:24997598

  12. Chromatin-associated degradation is defined by UBXN-3/FAF1 to safeguard DNA replication fork progression.

    PubMed

    Franz, André; Pirson, Paul A; Pilger, Domenic; Halder, Swagata; Achuthankutty, Divya; Kashkar, Hamid; Ramadan, Kristijan; Hoppe, Thorsten

    2016-01-01

    The coordinated activity of DNA replication factors is a highly dynamic process that involves ubiquitin-dependent regulation. In this context, the ubiquitin-directed ATPase CDC-48/p97 recently emerged as a key regulator of chromatin-associated degradation in several of the DNA metabolic pathways that assure genome integrity. However, the spatiotemporal control of distinct CDC-48/p97 substrates in the chromatin environment remained unclear. Here, we report that progression of the DNA replication fork is coordinated by UBXN-3/FAF1. UBXN-3/FAF1 binds to the licensing factor CDT-1 and additional ubiquitylated proteins, thus promoting CDC-48/p97-dependent turnover and disassembly of DNA replication factor complexes. Consequently, inactivation of UBXN-3/FAF1 stabilizes CDT-1 and CDC-45/GINS on chromatin, causing severe defects in replication fork dynamics accompanied by pronounced replication stress and eventually resulting in genome instability. Our work identifies a critical substrate selection module of CDC-48/p97 required for chromatin-associated protein degradation in both Caenorhabditis elegans and humans, which is relevant to oncogenesis and aging. PMID:26842564

  13. Chromatin-associated degradation is defined by UBXN-3/FAF1 to safeguard DNA replication fork progression

    PubMed Central

    Franz, André; Pirson, Paul A.; Pilger, Domenic; Halder, Swagata; Achuthankutty, Divya; Kashkar, Hamid; Ramadan, Kristijan; Hoppe, Thorsten

    2016-01-01

    The coordinated activity of DNA replication factors is a highly dynamic process that involves ubiquitin-dependent regulation. In this context, the ubiquitin-directed ATPase CDC-48/p97 recently emerged as a key regulator of chromatin-associated degradation in several of the DNA metabolic pathways that assure genome integrity. However, the spatiotemporal control of distinct CDC-48/p97 substrates in the chromatin environment remained unclear. Here, we report that progression of the DNA replication fork is coordinated by UBXN-3/FAF1. UBXN-3/FAF1 binds to the licensing factor CDT-1 and additional ubiquitylated proteins, thus promoting CDC-48/p97-dependent turnover and disassembly of DNA replication factor complexes. Consequently, inactivation of UBXN-3/FAF1 stabilizes CDT-1 and CDC-45/GINS on chromatin, causing severe defects in replication fork dynamics accompanied by pronounced replication stress and eventually resulting in genome instability. Our work identifies a critical substrate selection module of CDC-48/p97 required for chromatin-associated protein degradation in both Caenorhabditis elegans and humans, which is relevant to oncogenesis and aging. PMID:26842564

  14. Geochemical map of the North Fork John Day River Roadless Area, Grant County, Oregon

    USGS Publications Warehouse

    Evans, James G.

    1986-01-01

    The North Fork John Day River Roadless Area comprised 21,210 acres in the Umatilla and Wallowa-Whitman National Forests, Grant County, Oregon, about 30 miles northwest of Baker, Oregon. The irregularly shaped area extends for about 1 mile on both sides of a 25-mile segment of the North Fork John Day River from Big Creek on the west to North Fork John Day Campground on the east. Most of the roadless area is in the northern half of the Desolation Butte 15-minute quadrangle. The eastern end of the area is in parts of the Granite and Trout Meadows 7½-minute quadrangles.

  15. On cavitation in liquid helium in a flow due to a vibrating quartz fork

    NASA Astrophysics Data System (ADS)

    Blažková, M.; Schmoranzer, D.; Skrbek, L.

    2008-04-01

    Cavitation in normal and superfluid liquid He4 at saturated vapor pressure and slightly elevated pressures has been experimentally studied in a flow due to quartz forks vibrating at high amplitudes. Above the temperature- and pressure-dependent critical velocity, heterogeneous cavitation is observed both visually and electrically, as a breakdown of the resonance response of the fork. We compare our results with available experimental and discuss them using existing theoretical models. In particular, we show that thermal effects leading to local overheating of the vicinity of the fork have to be taken into account, especially in normal liquid He4.

  16. Q-factor optimization of a tuning-fork/fiber sensor for shear-force detection

    NASA Astrophysics Data System (ADS)

    Morville, Jérôme; Liu, Jinquan; Callegari, Andrea; Chergui, Majed

    2005-02-01

    We present the results of an experimental and theoretical study on the optimum design of shear-force sensors, used in scanning probe microscopes. We have optimized a configuration consisting of a tuning-fork/fiber-tip assembly, achieving quality factors (Q) exceeding 8000, and have presented a theoretical analysis of the design wherein the force holding the fiber and fork in contact is provided solely by elastic mechanical deformation, which allows full control of the performance of the system. On this basis, we constructed a high-quality-factor configuration with the fiber glued onto the tuning fork.

  17. A tuning fork gyroscope with compensated imbalance signal

    NASA Astrophysics Data System (ADS)

    Arnold, E.; Nuscheler, F.

    2007-05-01

    This paper is presenting a robust gyroscope sensor with an electrical and mechanical self-test option and the ability to suppress the quadrature error. The presented sensor is based on a tuning-fork working principle. The mechanical part is assembled in bulk-technology produced with a wet etching process. The two detection elements are manufactured with a standard CMOS-process and the material of the two thin-film actuators is AlN (aluminium-nitrid). The two actuators can be controlled independently from each other. Two electronic PCB's were developed for actuating and measurement. One is including the analogue signal path; the second PCB is the digital electronics consisting of a FPGA and other peripherals. The tuning fork is actuated in a primary oscillation mode also called drive mode. For keeping the oscillation in resonance, a digital PLL is used in a forced feedback loop. To have a constant energy in the drive mode an Amplitude-Gain-Control (AGC) is implemented. An appearing angular rate causes the corriolis-force which is actuating secondary oscillation, also called detection mode. The amplitude of this oscillation is proportional to the angular rate. The signal has a component resulting from the mechanical imbalance. To separate these two signal parts from each other a synchronous demodulator followed by a digital filter chain has been developed. To achieve the maximum suppression of the imbalance signal a control-loop is used to shift the phases of the two actuation signals. This creates an additional force that compensates the movement as a result of the mechanical imbalance. With the implementation of this control loop the performance of the sensor was increased. An enhanced temperature stability over operation was achieved with the means of this compensation.

  18. HENRY'S FORK AND SNAKE RIVER BASIN, IDAHO - WATER QUALITY REPORT, 1973

    EPA Science Inventory

    Reported problems in the Henrys Fork and Snake River Basin (17040202, 17040203, 17040201) include bacteria levels exceeding water quality standards, dissolved oxygen standards violations, and excessive algal blooms resulting in aesthetic problems and contributing to DO depression...

  19. ADAPTATION OPPORTUNITIES FOR SURFACE WATER RESOURCES IN THE ROARING FORK WATERSHED, COLORADO.

    EPA Science Inventory

    This project will assess climate-related impacts to the Roring Fork River (near Aspen, Colorado) and identify adaptive opportunities for surface water users, to support a larger global change assessment by the city of Aspen, CO (the Canary Initiative).

  20. 16 CFR 1512.14 - Requirements for fork and frame assembly.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.14 Requirements for fork and frame... significantly limits the steering angle over which the wheel can be turned. Sidewalk bicycles are exempt...

  1. 16 CFR 1512.14 - Requirements for fork and frame assembly.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.14 Requirements for fork and frame... significantly limits the steering angle over which the wheel can be turned. Sidewalk bicycles are exempt...

  2. 16 CFR 1512.14 - Requirements for fork and frame assembly.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.14 Requirements for fork and frame... significantly limits the steering angle over which the wheel can be turned. Sidewalk bicycles are exempt...

  3. 16 CFR 1512.14 - Requirements for fork and frame assembly.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Regulations § 1512.14 Requirements for fork and frame... significantly limits the steering angle over which the wheel can be turned. Sidewalk bicycles are exempt...

  4. Stalled DNA Replication Forks at the Endogenous GAA Repeats Drive Repeat Expansion in Friedreich's Ataxia Cells.

    PubMed

    Gerhardt, Jeannine; Bhalla, Angela D; Butler, Jill Sergesketter; Puckett, James W; Dervan, Peter B; Rosenwaks, Zev; Napierala, Marek

    2016-08-01

    Friedreich's ataxia (FRDA) is caused by the expansion of GAA repeats located in the Frataxin (FXN) gene. The GAA repeats continue to expand in FRDA patients, aggravating symptoms and contributing to disease progression. The mechanism leading to repeat expansion and decreased FXN transcription remains unclear. Using single-molecule analysis of replicated DNA, we detected that expanded GAA repeats present a substantial obstacle for the replication machinery at the FXN locus in FRDA cells. Furthermore, aberrant origin activation and lack of a proper stress response to rescue the stalled forks in FRDA cells cause an increase in 3'-5' progressing forks, which could enhance repeat expansion and hinder FXN transcription by head-on collision with RNA polymerases. Treatment of FRDA cells with GAA-specific polyamides rescues DNA replication fork stalling and alleviates expansion of the GAA repeats, implicating DNA triplexes as a replication impediment and suggesting that fork stalling might be a therapeutic target for FRDA. PMID:27425605

  5. Linking habitat quality with trophic performance of steelhead along forest gradients in the South Fork Trinity River Watershed, California

    USGS Publications Warehouse

    McCarthy, Sarah G.; Duda, Jeffrey J.; Emlen, John M.; Hodgson, Garth R.; Beauchamp, David A.

    2009-01-01

    We examined invertebrate prey, fish diet, and energy assimilation in relation to habitat variation for steelhead Oncorhynchus mykiss (anadromous rainbow trout) and rainbow trout in nine low-order tributaries of the South Fork Trinity River, northern California. These streams spanned a range of environmental conditions, which allowed us to use bioenergetics modeling to determine the relative effects of forest cover, stream temperature, season, and fish age on food consumption and growth efficiency. Evidence of seasonal shifts in reliance on aquatic versus terrestrial food sources was detected among forest cover categories and fish ages, although these categories were not robust indicators of O. mykiss condition and growth efficiency. Consumption estimates were generally less than 20% of maximum consumption, and fish lost weight in some streams during summer low-flow conditions when stream temperatures exceeded 15°C. Current 100-year climate change projections for California threaten to exacerbate negative growth patterns and may undermine the productivity of this steelhead population, which is currently not listed as endangered or threatened. To demonstrate the potential effect of global warming on fish growth, we ran three climate change scenarios in two representative streams. Simulated temperature increases ranging from 1.4°C to 5.5°C during the summer and from 1.5°C to 2.9C during the winter amplified the weight loss; estimated average growth for age-1 fish was 0.4–4.5 times lower than normal (low to high estimated temperature increase) in the warm stream and 0.05–0.8 times lower in the cool stream. We conclude that feeding rate and temperature during the summer currently limit the growth and productivity of steelhead and rainbow trout in low-order streams in the South Fork Trinity River basin and predict that climate change will have detrimental effects on steelhead growth as well as on macroinvertebrate communities and stream ecosystems in general.

  6. Regression of Replication Forks Stalled by Leading-strand Template Damage

    PubMed Central

    Gupta, Sankalp; Yeeles, Joseph T. P.; Marians, Kenneth J.

    2014-01-01

    Stalled replication forks are sites of chromosome breakage and the formation of toxic recombination intermediates that undermine genomic stability. Thus, replication fork repair and reactivation are essential processes. Among the many models of replication fork reactivation is one that invokes fork regression catalyzed by the strand exchange protein RecA as an intermediate in the processing of the stalled fork. We have investigated the replication fork regression activity of RecA using a reconstituted DNA replication system where the replisome is stalled by collision with leading-strand template damage. We find that RecA is unable to regress the stalled fork in the presence of the replisome and SSB. If the replication proteins are removed from the stalled fork, RecA will catalyze net regression as long as the Okazaki fragments are sealed. RecA-generated Holliday junctions can be detected by RuvC cleavage, although this is not a robust reaction. On the other hand, extensive branch migration by RecA, where a completely unwound product consisting of the paired nascent leading and lagging strands is produced, is observed under conditions where RuvC activity is suppressed. This branch migration reaction is inhibited by SSB, possibly accounting for the failure of RecA to generate products in the presence of the replication proteins. Interestingly, we find that the RecA-RuvC reaction is supported to differing extents, depending on the template damage; templates carrying a cyclopyrimidine dimer elicit more RecA-RuvC product than those carrying a synthetic abasic site. This difference could be ascribed to a higher affinity of RecA binding to DNAs carrying a thymidine dimer than to those with an abasic site. PMID:25138217

  7. Probing Liquid ^4He with Quartz Tuning Forks Using a Novel Multifrequency Lock-in Technique

    NASA Astrophysics Data System (ADS)

    Bradley, D. I.; Haley, R. P.; Kafanov, S.; Noble, M. T.; Pickett, G. R.; Tsepelin, V.; Vonka, J.; Wilcox, T.

    2016-09-01

    We report on a novel technique to measure quartz tuning forks, and possibly other vibrating objects, in a quantum fluid using a multifrequency lock-in amplifier. The multifrequency technique allows to measure the resonance curve of a vibrating object much faster than a conventional single frequency lock-in amplifier technique. Forks with resonance frequencies of 12 kHz and 16 kHz were excited and measured electro-mechanically either at a single frequency or at up to 40 different frequencies simultaneously around the same mechanical mode. The response of each fork was identical for both methods and validates the use of the multifrequency lock-in technique to probe properties of liquid helium at low fork velocities. Using both methods we measured the resonance frequency and drag of two 25-μ m-wide quartz tuning forks immersed in liquid ^4He in the temperature range from 4.2 K to 1.5 K at saturated vapour pressure. The damping and shift of resonance frequency experienced by both tuning forks at low velocities are well described by hydrodynamic contributions in the framework of the two-fluid model. The sensitivity of the 25-μ m-wide tuning forks is larger compared to similar 75-μ m-wide forks and in combination with the faster multifrequency lock-in technique could be used to improve thermometry in liquid ^4He. The multifrequency technique could also be used for studies of the onset of non-linear phenomena such as quantum turbulence and cavitation in superfluids.

  8. Probing Liquid ^4 He with Quartz Tuning Forks Using a Novel Multifrequency Lock-in Technique

    NASA Astrophysics Data System (ADS)

    Bradley, D. I.; Haley, R. P.; Kafanov, S.; Noble, M. T.; Pickett, G. R.; Tsepelin, V.; Vonka, J.; Wilcox, T.

    2016-06-01

    We report on a novel technique to measure quartz tuning forks, and possibly other vibrating objects, in a quantum fluid using a multifrequency lock-in amplifier. The multifrequency technique allows to measure the resonance curve of a vibrating object much faster than a conventional single frequency lock-in amplifier technique. Forks with resonance frequencies of 12 kHz and 16 kHz were excited and measured electro-mechanically either at a single frequency or at up to 40 different frequencies simultaneously around the same mechanical mode. The response of each fork was identical for both methods and validates the use of the multifrequency lock-in technique to probe properties of liquid helium at low fork velocities. Using both methods we measured the resonance frequency and drag of two 25-μ m-wide quartz tuning forks immersed in liquid ^4 He in the temperature range from 4.2 K to 1.5 K at saturated vapour pressure. The damping and shift of resonance frequency experienced by both tuning forks at low velocities are well described by hydrodynamic contributions in the framework of the two-fluid model. The sensitivity of the 25-μ m-wide tuning forks is larger compared to similar 75-μ m-wide forks and in combination with the faster multifrequency lock-in technique could be used to improve thermometry in liquid ^4 He. The multifrequency technique could also be used for studies of the onset of non-linear phenomena such as quantum turbulence and cavitation in superfluids.

  9. The Sound Field around a Tuning Fork and the Role of a Resonance Box

    ERIC Educational Resources Information Center

    Bogacz, Bogdan F.; Pedziwiatr, Antoni T.

    2015-01-01

    Atypical two-tine tuning fork is barely audible when held vibrating at an arm's length. It is enough, however, to touch its base to a table or, better, to a resonance box and the emitted sound becomes much louder. An inquiring student may pose questions: (1) Why is a bare tuning fork such a weak emitter of sound? (2) What is the role of the…

  10. DNA2 drives processing and restart of reversed replication forks in human cells

    PubMed Central

    Thangavel, Saravanabhavan; Berti, Matteo; Levikova, Maryna; Pinto, Cosimo; Gomathinayagam, Shivasankari; Vujanovic, Marko; Zellweger, Ralph; Moore, Hayley; Lee, Eu Han; Hendrickson, Eric A.; Cejka, Petr; Stewart, Sheila; Lopes, Massimo

    2015-01-01

    Accurate processing of stalled or damaged DNA replication forks is paramount to genomic integrity and recent work points to replication fork reversal and restart as a central mechanism to ensuring high-fidelity DNA replication. Here, we identify a novel DNA2- and WRN-dependent mechanism of reversed replication fork processing and restart after prolonged genotoxic stress. The human DNA2 nuclease and WRN ATPase activities functionally interact to degrade reversed replication forks with a 5′-to-3′ polarity and promote replication restart, thus preventing aberrant processing of unresolved replication intermediates. Unexpectedly, EXO1, MRE11, and CtIP are not involved in the same mechanism of reversed fork processing, whereas human RECQ1 limits DNA2 activity by preventing extensive nascent strand degradation. RAD51 depletion antagonizes this mechanism, presumably by preventing reversed fork formation. These studies define a new mechanism for maintaining genome integrity tightly controlled by specific nucleolytic activities and central homologous recombination factors. PMID:25733713

  11. Checkpoint-dependent RNR induction promotes fork restart after replicative stress.

    PubMed

    Morafraile, Esther C; Diffley, John F X; Tercero, José Antonio; Segurado, Mónica

    2015-01-01

    The checkpoint kinase Rad53 is crucial to regulate DNA replication in the presence of replicative stress. Under conditions that interfere with the progression of replication forks, Rad53 prevents Exo1-dependent fork degradation. However, although EXO1 deletion avoids fork degradation in rad53 mutants, it does not suppress their sensitivity to the ribonucleotide reductase (RNR) inhibitor hydroxyurea (HU). In this case, the inability to restart stalled forks is likely to account for the lethality of rad53 mutant cells after replication blocks. Here we show that Rad53 regulates replication restart through the checkpoint-dependent transcriptional response, and more specifically, through RNR induction. Thus, in addition to preventing fork degradation, Rad53 prevents cell death in the presence of HU by regulating RNR-expression and localization. When RNR is induced in the absence of Exo1 and RNR negative regulators, cell viability of rad53 mutants treated with HU is increased and the ability of replication forks to restart after replicative stress is restored. PMID:25601385

  12. Checkpoint-dependent RNR induction promotes fork restart after replicative stress

    PubMed Central

    Morafraile, Esther C.; Diffley, John F. X.; Tercero, José Antonio; Segurado, Mónica

    2015-01-01

    The checkpoint kinase Rad53 is crucial to regulate DNA replication in the presence of replicative stress. Under conditions that interfere with the progression of replication forks, Rad53 prevents Exo1-dependent fork degradation. However, although EXO1 deletion avoids fork degradation in rad53 mutants, it does not suppress their sensitivity to the ribonucleotide reductase (RNR) inhibitor hydroxyurea (HU). In this case, the inability to restart stalled forks is likely to account for the lethality of rad53 mutant cells after replication blocks. Here we show that Rad53 regulates replication restart through the checkpoint-dependent transcriptional response, and more specifically, through RNR induction. Thus, in addition to preventing fork degradation, Rad53 prevents cell death in the presence of HU by regulating RNR-expression and localization. When RNR is induced in the absence of Exo1 and RNR negative regulators, cell viability of rad53 mutants treated with HU is increased and the ability of replication forks to restart after replicative stress is restored. PMID:25601385

  13. Restriction of Replication Fork Regression Activities by a Conserved SMC Complex

    PubMed Central

    Xue, Xiaoyu; Choi, Koyi; Bonner, Jaclyn; Chiba, Tamara; Kwon, Youngho; Xu, Yuanyuan; Sanchez, Humberto; Wyman, Claire; Niu, Hengyao; Zhao, Xiaolan; Sung, Patrick

    2014-01-01

    SUMMARY Conserved, multi-tasking DNA helicases mediate diverse DNA transactions and are relevant for human disease pathogenesis. These helicases and their regulation help maintain genome stability during DNA replication and repair. We show that the structural maintenance of chromosome complex Smc5-Smc6 restrains the replication fork regression activity of Mph1 helicase, but not its D-loop disruptive activity. This regulatory mechanism enables flexibility in replication fork repair without interfering with DNA break repair. In vitro studies find that Smc5-Smc6 binds to a Mph1 region required for efficient fork regression, preventing assembly of Mph1 oligomers at the junction of DNA forks. In vivo impairment of this regulatory mechanism compensates for the inactivation of another fork regression helicase and increases reliance on joint DNA structure removal or avoidance. Our findings provide molecular insights into replication fork repair regulation and uncover a role of Smc5-Smc6 in directing Mph1 activity towards a specific biochemical outcome. PMID:25439736

  14. RNF4 and PLK1 are required for replication fork collapse in ATR-deficient cells.

    PubMed

    Ragland, Ryan L; Patel, Sima; Rivard, Rebecca S; Smith, Kevin; Peters, Ashley A; Bielinsky, Anja-Katrin; Brown, Eric J

    2013-10-15

    The ATR-CHK1 axis stabilizes stalled replication forks and prevents their collapse into DNA double-strand breaks (DSBs). Here, we show that fork collapse in Atr-deleted cells is mediated through the combined effects the sumo targeted E3-ubiquitin ligase RNF4 and activation of the AURKA-PLK1 pathway. As indicated previously, Atr-deleted cells exhibited a decreased ability to restart DNA replication following fork stalling in comparison with control cells. However, suppression of RNF4, AURKA, or PLK1 returned the reinitiation of replication in Atr-deleted cells to near wild-type levels. In RNF4-depleted cells, this rescue directly correlated with the persistence of sumoylation of chromatin-bound factors. Notably, RNF4 repression substantially suppressed the accumulation of DSBs in ATR-deficient cells, and this decrease in breaks was enhanced by concomitant inhibition of PLK1. DSBs resulting from ATR inhibition were also observed to be dependent on the endonuclease scaffold protein SLX4, suggesting that RNF4 and PLK1 either help activate the SLX4 complex or make DNA replication fork structures accessible for subsequent SLX4-dependent cleavage. Thus, replication fork collapse following ATR inhibition is a multistep process that disrupts replisome function and permits cleavage of the replication fork. PMID:24142876

  15. Note: Enhanced energy harvesting from low-frequency magnetic fields utilizing magneto-mechano-electric composite tuning-fork.

    PubMed

    Yang, Aichao; Li, Ping; Wen, Yumei; Yang, Chao; Wang, Decai; Zhang, Feng; Zhang, Jiajia

    2015-06-01

    A magnetic-field energy harvester using a low-frequency magneto-mechano-electric (MME) composite tuning-fork is proposed. This MME composite tuning-fork consists of a copper tuning fork with piezoelectric Pb(Zr(1-x)Ti(x))O3 (PZT) plates bonded near its fixed end and with NdFeB magnets attached at its free ends. Due to the resonance coupling between fork prongs, the MME composite tuning-fork owns strong vibration and high Q value. Experimental results show that the proposed magnetic-field energy harvester using the MME composite tuning-fork exhibits approximately 4 times larger maximum output voltage and 7.2 times higher maximum power than the conventional magnetic-field energy harvester using the MME composite cantilever. PMID:26133877

  16. Note: Enhanced energy harvesting from low-frequency magnetic fields utilizing magneto-mechano-electric composite tuning-fork

    NASA Astrophysics Data System (ADS)

    Yang, Aichao; Li, Ping; Wen, Yumei; Yang, Chao; Wang, Decai; Zhang, Feng; Zhang, Jiajia

    2015-06-01

    A magnetic-field energy harvester using a low-frequency magneto-mechano-electric (MME) composite tuning-fork is proposed. This MME composite tuning-fork consists of a copper tuning fork with piezoelectric Pb(Zr1-xTix)O3 (PZT) plates bonded near its fixed end and with NdFeB magnets attached at its free ends. Due to the resonance coupling between fork prongs, the MME composite tuning-fork owns strong vibration and high Q value. Experimental results show that the proposed magnetic-field energy harvester using the MME composite tuning-fork exhibits approximately 4 times larger maximum output voltage and 7.2 times higher maximum power than the conventional magnetic-field energy harvester using the MME composite cantilever.

  17. BIOLOGICAL MONITORING PROGRAM FOR EAST FORK POPLAR CREEK

    SciTech Connect

    ADAMS, S.M.; BEATY, T.W.; BRANDT, C.C.; CHRISTENSEN, S.W.; CICERONE, D.S.

    1998-09-09

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  18. BIOLOGICAL MONITORING PROGRAM FOR EAST FORK POPLAR CREEK

    SciTech Connect

    ADAMS, S.M.; ASHWOOD, T.L.; BEATY, T.W.; BRANDT, C.C.

    1997-10-24

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y- 12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  19. Water resources of the Little Fork River watershed, northeastern Minnesota

    USGS Publications Warehouse

    Helgesen, John O.; Lindholm, Gerald F.; Ericson, Donald W.

    1976-01-01

    The Little Fork River watershed is one of 39 watershed units designated by the Minnesota Department of Natural Resources for evaluation of the State 's water resources. Included is an appraisal of the occurrence, quantity, quality, and availability of ground and surface waters. Water resources are not intensively developed anywhere in the watershed. Essentially all water used is withdrawn from ground-water sources, mainly glacial drift, which ranges from 0 to over 200 feet (61 meters) in thickness. Buried sand and gravel in the drift is the most favorable source for development. Most ground water is of the calcium or calcium magnesium bicarbonate type. The degree of mineralization generally increases downgradient in the flow system. Ground water is commonly very hard and high in iron and manganese. Lakes and wetlands have a natural regulating effect on streamflow. Water in streams is of the calcium bicarbonate type. The amount of mineralization reflects surficial geology, being greatest in streams draining glacial-lake sediments and least in streams draining areas of sand lakes. Color and iron concentration in stream waters generally exceed recommended domestic consumption limits.

  20. Biological monitoring program for East Fork Poplar Creek

    SciTech Connect

    Adams, S.M.; Ashwood, T.L.; Beaty, T.W.; Brandt, C.C.; Christensen, S.W.; Cicerone, D.S.; Greeley, M.S. Jr.; Hill, W.R.; Kszos, L.S.

    1997-04-18

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the complex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC. These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumulation studies, and (4) ecological surveys of the periphyton, benthic macroinvertebrate, and fish communities.

  1. Tim/Timeless, a member of the replication fork protection complex, operates with the Warsaw breakage syndrome DNA helicase DDX11 in the same fork recovery pathway.

    PubMed

    Calì, Federica; Bharti, Sanjay Kumar; Perna, Roberta Di; Brosh, Robert M; Pisani, Francesca M

    2016-01-29

    We present evidence that Tim establishes a physical and functional interaction with DDX11, a super-family 2 iron-sulfur cluster DNA helicase genetically linked to the chromosomal instability disorder Warsaw breakage syndrome. Tim stimulates DDX11 unwinding activity on forked DNA substrates up to 10-fold and on bimolecular anti-parallel G-quadruplex DNA structures and three-stranded D-loop approximately 4-5-fold. Electrophoretic mobility shift assays revealed that Tim enhances DDX11 binding to DNA, suggesting that the observed stimulation derives from an improved ability of DDX11 to interact with the nucleic acid substrate. Surface plasmon resonance measurements indicate that DDX11 directly interacts with Tim. DNA fiber track assays with HeLa cells exposed to hydroxyurea demonstrated that Tim or DDX11 depletion significantly reduced replication fork progression compared to control cells; whereas no additive effect was observed by co-depletion of both proteins. Moreover, Tim and DDX11 are epistatic in promoting efficient resumption of stalled DNA replication forks in hydroxyurea-treated cells. This is consistent with the finding that association of the two endogenous proteins in the cell extract chromatin fraction is considerably increased following hydroxyurea exposure. Overall, our studies provide evidence that Tim and DDX11 physically and functionally interact and act in concert to preserve replication fork progression in perturbed conditions. PMID:26503245

  2. [Heritability of body weight and fork length for Oncorhynchus masou masou].

    PubMed

    Zhang, Yu-Yong; Jia, Zhi-Ying; Bai, Qing-Li; Chen, Shu-Qiang; Shi, Lian-Yu; Wang, Bing-Qian

    2013-02-01

    Body weight and body length have been considered as the most important production traits for the fish genetic improvement. For cold-water fish, body length was usually substituted by fork length. In order to estimate the heritability of body weight and fork length of the sixth generation Oncorhynchus masou masou, which was introduced into China, the method of unbalanced nest design and an artificial insemination technigue were used. Twenty-nine full-sib families and fourteen half-sib families were obtained. Body weight and fork length of O. masou masou were measured in 12 and 24 months after fertilization. Based on full-sib and half-sib families data, the causal components of phenotypic variance were calculated. The results showed that, (1) during the whole growth phase of O. masou masou, the coefficient variation (CV) of fork length was higher than body weight, and CV of 12-month old was higher than that of 24-month old; (2) body weight and fork length of O. masou masou among sires and dams among sires were significant difference (P<0.01) both at 12 months and at 24 months; (3) the maternal component estimates were significantly larger than those of paternal ones for body weight and fork length traits both at 12 months and at 24 months; (4) for 12 months of O. masou masou the heritabilities of body weight and fork length were 0.41~0.51 and 0.46~0.54, respectively. For 24 months the values were 0.55~0.60 and 0.53~0.59, respectively; and (5) it was concluded that the heritability of growth traits in O. masou masou was relatively high and this highlights the potential to improve its growth through selective breeding. This study shows important data supporting for further genetic improvement of O. masou masou. PMID:23448933

  3. Biological Monitoring Program for East Fork Poplar Creek

    SciTech Connect

    Adams, S.M.; Christensen, S.W.; Greeley, M.S.jr; Hill, W.R.; Kszos, L.A.; McCarthy, J.F.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.

    1998-10-15

    In May 1985, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge Y-12 Plant. As a condition of the permit, a Biologicai Monitoring and Abatement Program (BMAP) was developed to demonstrate that the effluent limitations established for the Y-12 Plant protect the classified uses of the receiving stream (East Fork Poplar Creek; EFPC), in particular, the growth and propagation of aquatic life (Lear et al. 1989). A second objective of the BMAP is to document the ecological effects resulting from the implementation of a water pollution control program designed to eliminate direct discharges of wastewaters to EFPC and to minimize the inadvertent release of pollutants to the environment. Because of the compiex nature of the discharges to EFPC and the temporal and spatial variability in the composition of the discharges, a comprehensive, integrated approach to biological monitoring was developed. A new permit was issued to the Y-12 Plant on April 28, 1995 and became effective on July 1, 1995. Biological monitoring continues to be required under the new permit. The BMAP consists of four major tasks that reflect different but complementary approaches to evaluating the effects of the Y-12 Plant discharges on the aquatic integrity of EFPC, These tasks are (1) toxicity monitoring, (2) biological indicator studies, (3) bioaccumuiation studies, and (4) ecological surveys of the periphyton, benthic macro invertebrate, and fish communities. Monitoring is currently being conducted at five sites, although sites maybe excluded and/or others added depending upon the specific objectives of the various tasks. Criteria used in selecting the sites include: (1) location of sampling sites used in other studies, (2) known or suspected sources of downstream impacts, (3) proximity to U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) boundaries, (4) concentration of mercury in the adjacent floodplain, (5) appropriate habitat distribution, and (6

  4. UvrD controls the access of recombination proteins to blocked replication forks

    PubMed Central

    Lestini, Roxane; Michel, Bénédicte

    2007-01-01

    Blocked replication forks often need to be processed by recombination proteins prior to replication restart. In Escherichia coli, the UvrD repair helicase was recently shown to act at inactivated replication forks, where it counteracts a deleterious action of RecA. Using two mutants affected for different subunits of the polymerase III holoenzyme (Pol IIIh), we show here that the anti-RecA action of UvrD at blocked forks reflects two different activities of this enzyme. A defective UvrD mutant is able to antagonize RecA in cells affected for the Pol IIIh catalytic subunit DnaE. In this mutant, RecA action at blocked forks specifically requires the protein RarA (MgsA). We propose that UvrD prevents RecA binding, possibly by counteracting RarA. In contrast, at forks affected for the Pol IIIh clamp (DnaN), RarA is not required for RecA binding and the ATPase function of UvrD is essential to counteract RecA, supporting the idea that UvrD removes RecA from DNA. UvrD action on RecA is conserved in evolution as it can be performed in E. coli by the UvrD homologue from Bacillus subtilis, PcrA. PMID:17641684

  5. Quartz tuning-fork oscillations in He II and drag coefficient

    NASA Astrophysics Data System (ADS)

    Gritsenko, I. A.; Zadorozhko, A. A.; Neoneta, A. S.; Chagovets, V. K.; Sheshin, G. A.

    2011-07-01

    The temperature dependencies of drag coefficient for quartz tuning forks of various geometric dimensions, immersed in the He II, were determined experimentally in the temperature range 0.1-3 K. It is identified, that these dependencies are similar, but the values of drag coefficient are different for tuning forks with different geometric dimensions. It is shown, that the obtained specific drag coefficient depends only on the temperature and frequency of vibrations, when the value of drag coefficient is normalized to the surface area of moving tuning-fork prong. The temperature dependencies of normalized drag coefficient for the tuning forks of various dimensions, wire, and microsphere, oscillating in the Не II, are compared. It is shown, that in the ballistic regime of scattering of quasiparticles, these dependencies are identical and have a slope proportional to T4, which is determined by the density of thermal excitations. In the hydrodynamic regime at T > 0.5 K, the behavior of the temperature dependence of specific drag coefficient is affected by the size and frequency of vibrating body. The empirical relation, which allows to describe the behavior of specific drag coefficient for vibrating tuning forks, microsphere, and wire everywhere over the temperature region and at various frequencies, is proposed.

  6. UvrD controls the access of recombination proteins to blocked replication forks.

    PubMed

    Lestini, Roxane; Michel, Bénédicte

    2007-08-22

    Blocked replication forks often need to be processed by recombination proteins prior to replication restart. In Escherichia coli, the UvrD repair helicase was recently shown to act at inactivated replication forks, where it counteracts a deleterious action of RecA. Using two mutants affected for different subunits of the polymerase III holoenzyme (Pol IIIh), we show here that the anti-RecA action of UvrD at blocked forks reflects two different activities of this enzyme. A defective UvrD mutant is able to antagonize RecA in cells affected for the Pol IIIh catalytic subunit DnaE. In this mutant, RecA action at blocked forks specifically requires the protein RarA (MgsA). We propose that UvrD prevents RecA binding, possibly by counteracting RarA. In contrast, at forks affected for the Pol IIIh clamp (DnaN), RarA is not required for RecA binding and the ATPase function of UvrD is essential to counteract RecA, supporting the idea that UvrD removes RecA from DNA. UvrD action on RecA is conserved in evolution as it can be performed in E. coli by the UvrD homologue from Bacillus subtilis, PcrA. PMID:17641684

  7. South Fork Snake River/Palisades Wildlife Mitigation Project: Environmental assessment

    SciTech Connect

    1995-09-01

    BPA proposes to fund the implementation of the South Fork Snake River Programmatic Management Plan to compensate for losses of wildlife and wildlife habitat due to hydroelectric development at Palisades Dam. The Idaho Department of Fish and Game drafted the plan, which was completed in May 1993. This plan recommends land and conservation easement acquisition and wildlife habitat enhancement measures. These measures would be implemented on selected lands along the South Fork of the Snake River between Palisades Dam and the confluence with the Henry`s Fork, and on portions of the Henry`s Fork located in Bonneville, Madison, and Jefferson Counties, Idaho. BPA has prepared an Environmental Assessment evaluating the proposed project. The EA also incorporates by reference the analyses in the South Fork Snake River Activity/Operations Plan and EA prepared jointly in 1991 by the Bureau of Land Management and the Forest Service. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement (EIS) is not required and BPA is issuing this FONSI.

  8. Vibratory Gyro-Sensor Using Vertically Set Quartz Crystal Trident-Type Tuning Fork Resonator

    NASA Astrophysics Data System (ADS)

    Shiratori, Norihiko; YoshiroTomikawa, YoshiroTomikawa; Ohnishi, Kazumasa

    1999-05-01

    In this study we deal with a new type of vibratory gyro-sensor using a vertically set quartz crystal trident-type tuning fork resonator. The sensor is made of X-cut quartz crystal wafer formed by rotating 2° about the X-axis, applying the wire saw cutting method. The slits that form three arms are cut along the Y-axis direction. In such a trident-type tuning fork resonator, two resonance vibration modes are used: one has vibrational displacement in the vertical direction (X-axis) of the tuning fork plane and the other has that in the horizontal direction (Z‧-axis). When an angular rate (ΩY‧) around the Y‧-axis is applied to the trident-type tuning fork gyro-sensor vibrating in the V-MODE, Coriolis forces, due to the ΩY‧, are applied on the three arms in the X‧-axis direction and the H-MODE vibration is induced. Therefore, the angular rate (ΩY‧) can be determined by detecting the signals of H-MODE vibration. The experimental results have proved that the vibratory gyro-sensor that uses such a quartz crystal tuning fork resonator has good characteristics.

  9. Tuning fork test utilization in detection of fractures: a review of the literature

    PubMed Central

    Kazemi, Mohsen

    1999-01-01

    A review of the literature was conducted to find relevant publications on the validity, reliability and utilization of the tuning fork test in detection of stress and simple fractures. Medline 1966-1998, Cumulative Index to Nursing and Allied Health Literature (CINAHL) 1982-1997, Science Citation Index 1961-1997, Index to chiropractic literature 1980-1998 and Chiropractic Research Archives Collection 1984-1990 data bases were searched. Key words such as tuning fork, vibration, diapason, fracture, stress fracture were used. The literature regarding the utilization of the tuning fork test in detection of fractures is very scarce. There was no study found in the above data bases on the validity and or reliability of the tuning fork test in detection of simple acute fractures. This review of the literature indicates the necessity of such a study since the tuning fork test has been used on the field for diagnosis of simple acute fractures. Imagesp124-ap124-bp124-cp124-dp124-e

  10. Regional Ecorisk Field investigation, upper Clark Fork River Basin

    SciTech Connect

    Pastorok, R.; LaTier, A.; Ginn, T.

    1995-12-31

    The Regional Ecorisk Field Investigation was conducted at the Clark Fork River Superfund Site (Montana) to evaluate the relationships between plant communities and tailings deposits in riparian habitats and to evaluate food-chain transfer of trace elements to selected wildlife species. Stations were selected to represent a range of vegetation biomass (or cover) values and apparent impact of trace elements, with some areas of lush vegetation, some areas of mostly unvegetated soil (e.g., < 30 percent plant cover), and a gradient in between. For the evaluation of risk to wildlife, bioaccumulation of metals was evaluated in native or naturalized plants, terrestrial invertebrates, and the deer mouse (Peromyscus maniculatus). Potential reproductive effects in the deer mouse were evaluated by direct measurements. For other wildlife species, bioaccumulation data were interpreted in the context of food web exposure models. Total biomass and species richness of riparian plant communities are related to tailings content of soil as indicated by pH and metals concentrations. Risk to populations of omnivorous small mammals such as the deer mouse was not significant. Relative abundance and reproductive condition of the deer mouse were normal, even in areas of high metals enrichment. Based on exposure models and site-specific tissue residue data for dietary species, risk to local populations of predators such as red fox and American kestrel that feed on deer mice and terrestrial invertebrates is not significant. Risk to herbivores related to metals bioaccumulation in plant tissues is not significant. Population level effects in deer and other large wildlife are not expected because of the large home ranges of such species and compensatory demographic factors.

  11. The Coefficient of the Voltage Induced Frequency Shift Measurement on a Quartz Tuning Fork

    PubMed Central

    Hou, Yubin; Lu, Qingyou

    2014-01-01

    We have measured the coefficient of the voltage induced frequency shift (VIFS) of a 32.768 KHz quartz tuning fork. Three vibration modes were studied: one prong oscillating, two prongs oscillating in the same direction, and two prongs oscillating in opposite directions. They all showed a parabolic dependence of the eigen-frequency shift on the bias voltage applied across the fork, due to the voltage-induced internal stress, which varies as the fork oscillates. The average coefficient of the VIFS effect is as low as several hundred nano-Hz per millivolt, implying that fast-response voltage-controlled oscillators and phase-locked loops with nano-Hz resolution can be built. PMID:25414971

  12. Failure of origin activation in response to fork stalling leads to chromosomal instability at fragile sites.

    PubMed

    Ozeri-Galai, Efrat; Lebofsky, Ronald; Rahat, Ayelet; Bester, Assaf C; Bensimon, Aaron; Kerem, Batsheva

    2011-07-01

    Perturbed DNA replication in early stages of cancer development induces chromosomal instability preferentially at fragile sites. However, the molecular basis for this instability is unknown. Here, we show that even under normal growth conditions, replication fork progression along the fragile site, FRA16C, is slow and forks frequently stall at AT-rich sequences, leading to activation of additional origins to enable replication completion. Under mild replication stress, the frequency of stalling at AT-rich sequences is further increased. Strikingly, unlike in the entire genome, in the FRA16C region additional origins are not activated, suggesting that all potential origins are already activated under normal conditions. Thus, the basis for FRA16C fragility is replication fork stalling at AT-rich sequences and inability to activate additional origins under replication stress. Our results provide a mechanism explaining the replication stress sensitivity of fragile sites and thus, the basis for genomic instability during early stages of cancer development. PMID:21726815

  13. The DNA repair helicase UvrD is essential for replication fork reversal in replication mutants.

    PubMed

    Flores, Maria Jose; Bidnenko, Vladimir; Michel, Bénédicte

    2004-10-01

    Replication forks arrested by inactivation of the main Escherichia coli DNA polymerase (polymerase III) are reversed by the annealing of newly synthesized leading- and lagging-strand ends. Reversed forks are reset by the action of RecBC on the DNA double-strand end, and in the absence of RecBC chromosomes are linearized by the Holliday junction resolvase RuvABC. We report here that the UvrD helicase is essential for RuvABC-dependent chromosome linearization in E. coli polymerase III mutants, whereas its partners in DNA repair (UvrA/B and MutL/S) are not. We conclude that UvrD participates in replication fork reversal in E. coli. PMID:15375374

  14. South Fork Clearwater River Habitat Enhancement, Crooked and Red Rivers : Annual Report, 1989.

    SciTech Connect

    Baer, William H.

    1990-01-01

    In 1983, the Nez Perce National Forest and the Bonneville Power Administration entered into an interagency agreement to enhance and improve habitat for two anadromous fish species, spring chinook salmon (Oncorhynchus tshawyscha) and summer steelhead trout (Onchorhyncus mykiss), in the South Fork Clearwater River tributaries. The South Fork Clearwater River was dammed in 1927 for hydroelectric development. Anadromous fish runs were virtually eliminated until the dam was removed in 1962. To complicate the problem, upstream spawning and rearing habitats were severely impacted by dredge and hydraulic mining, road building, timber harvest, and over-grazing. Fish habitat improvement projects under the above contract are being carried out in two major tributaries to the South Fork Clearwater River. Both the Red River and the Crooked River projects began in 1983 and will be completed in 1990. 12 figures., 1 tab.

  15. Ubiquitinated Fancd2 recruits Fan1 to stalled replication forks to prevent genome instability.

    PubMed

    Lachaud, Christophe; Moreno, Alberto; Marchesi, Francesco; Toth, Rachel; Blow, J Julian; Rouse, John

    2016-02-19

    Mono-ubiquitination of Fancd2 is essential for repairing DNA interstrand cross-links (ICLs), but the underlying mechanisms are unclear. The Fan1 nuclease, also required for ICL repair, is recruited to ICLs by ubiquitinated (Ub) Fancd2. This could in principle explain how Ub-Fancd2 promotes ICL repair, but we show that recruitment of Fan1 by Ub-Fancd2 is dispensable for ICL repair. Instead, Fan1 recruitment--and activity--restrains DNA replication fork progression and prevents chromosome abnormalities from occurring when DNA replication forks stall, even in the absence of ICLs. Accordingly, Fan1 nuclease-defective knockin mice are cancer-prone. Moreover, we show that a Fan1 variant in high-risk pancreatic cancers abolishes recruitment by Ub-Fancd2 and causes genetic instability without affecting ICL repair. Therefore, Fan1 recruitment enables processing of stalled forks that is essential for genome stability and health. PMID:26797144

  16. 76 FR 50171 - Notice of Intent To Prepare an Environmental Impact Statement for the Henrys Fork Salinity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-12

    ... the Henrys Fork Salinity Control Project Plan, Sweetwater and Uinta Counties, WY; Daggett and Summit... Statement (EIS) for the Henrys Fork Salinity Control Project Plan (SCPP). The NRCS will be the lead agency... Improvements'' alternative assumes a salinity control project will be implemented. Existing financial...

  17. 33 CFR 165.552 - Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey. 165.552 Section 165.552 Navigation and Navigable... Coast Guard District § 165.552 Security Zone; Oyster Creek Generation Station, Forked River,...

  18. 33 CFR 165.552 - Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey. 165.552 Section 165.552 Navigation and Navigable... Coast Guard District § 165.552 Security Zone; Oyster Creek Generation Station, Forked River,...

  19. 33 CFR 165.552 - Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey. 165.552 Section 165.552 Navigation and Navigable... Coast Guard District § 165.552 Security Zone; Oyster Creek Generation Station, Forked River,...

  20. 33 CFR 165.552 - Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey. 165.552 Section 165.552 Navigation and Navigable... Coast Guard District § 165.552 Security Zone; Oyster Creek Generation Station, Forked River,...

  1. 33 CFR 165.552 - Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Security Zone; Oyster Creek Generation Station, Forked River, Ocean County, New Jersey. 165.552 Section 165.552 Navigation and Navigable... Coast Guard District § 165.552 Security Zone; Oyster Creek Generation Station, Forked River,...

  2. 77 FR 66865 - Record of Decision for the Oil and Gas Management Plan, Big South Fork National River and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-07

    ... National Park Service Record of Decision for the Oil and Gas Management Plan, Big South Fork National River... (ROD) for the Oil and Gas Management Plan (Plan) for Big South Fork National River and Recreation Area... impacts from oil and gas development. The plan will guide oil and gas management in Big South...

  3. 77 FR 34337 - Uinta-Wasatch-Cache National Forest; Evanston-Mountain View Ranger District; Utah; Smiths Fork...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-11

    ... Forest Service Uinta-Wasatch-Cache National Forest; Evanston-Mountain View Ranger District; Utah; Smiths... submitting a correction to the notice of intent for the Smiths Fork Vegetation Restoration Project published... period for the Smiths Fork Vegetation Restoration Project has been extended. Comments concerning...

  4. Delayed complete gastric outlet obstruction due to a dinner fork: report of a case.

    PubMed

    Atila, Koray; Unek, Tarkan; Sevinç, Ali Ibrahim; Aydoğan, Baki; Serin, Ayfer; Bora, Seymen; Gülay, Hüseyin

    2010-07-01

    Ingestion of foreign bodies can be a common problem especially among children, alcoholics, psychiatric patients, and senile patients, but ingestion of a metallic dinner fork is uncommon. Foreign bodies with smooth edges usually do not pose significant problems, but a sharp foreign object that is not retrieved at the earliest may penetrate the wall and cause complications. Ingested foreign bodies usually pass the intestinal tract without problems, and perforation occurs in less than 1%. In this paper, a case of rare gastric outlet obstruction due to a dinner fork, which was ingested 25 days before, is reported. PMID:20849060

  5. Real-Time Ozone Detection Based on a Microfabricated Quartz Crystal Tuning Fork Sensor

    PubMed Central

    Wang, Rui; Tsow, Francis; Zhang, Xuezhi; Peng, Jhih-Hong; Forzani, Erica S.; Chen, Yongsheng; Crittenden, John C.; Destaillats, Hugo; Tao, Nongjian

    2009-01-01

    A chemical sensor for ozone based on an array of microfabricated tuning forks is described. The tuning forks are highly sensitive and stable, with low power consumption and cost. The selective detection is based on the specific reaction of the polymer with ozone. With a mass detection limit of ∼2 pg/mm2 and response time of 1 second, the sensor coated with a polymer sensing material can detect ppb-level ozone in air. The sensor is integrated into a miniaturized wearable device containing a detection circuit, filtration, battery and wireless communication chip, which is ideal for personal and microenvironmental chemical exposure monitoring. PMID:22346720

  6. Calibrating the frequency of tuning forks by means of Lissajous figures

    NASA Astrophysics Data System (ADS)

    Quereda, Jorge; Ramón, Marina; Silva, Blanca; Hinarejos, Juan José; Rodrigo, José Gabriel; Farías, Daniel

    2011-05-01

    We produce Lissajous figures by modulating a laser beam along two perpendicular directions by means of two tuning forks. When the ratio of the resonant frequencies of the tuning forks is a small rational number, Lissajous figures are clearly resolved on a screen. Because the ratio of frequencies is never exactly a rational number, a phase drift of the Lissajous figures is observed as a function of time. If the period of this phase drift is measured, variations in the resonant frequencies as small as 0.01 Hz can be detected.

  7. Measurements of Vortex Line Density Generated by a Quartz Tuning Fork in Superfluid 4He

    NASA Astrophysics Data System (ADS)

    Jackson, M. J.; Kolosov, O.; Schmoranzer, D.; Skrbek, L.; Tsepelin, V.; Woods, A. J.

    2016-05-01

    We present proof-of-concept measurements of the vortex line density generated by a quartz tuning fork resonator probed by the attenuation of second sound in superfluid ^4He at 1.6 K. The force-velocity response of a quartz tuning fork operating at a frequency of 31 kHz exhibited the onset of extra damping at a velocity of 0.5 ms^{-1}. Attenuation of the 5th resonant mode of second sound was observed at the same velocity, indicating the production of vortex lines. Our measurements demonstrate that an increase of the drag coefficient corresponds to the development of quantum turbulence.

  8. Regulating telomere length from the inside out: the replication fork model

    PubMed Central

    2016-01-01

    Telomere length is regulated around an equilibrium set point. Telomeres shorten during replication and are lengthened by telomerase. Disruption of the length equilibrium leads to disease; thus, it is important to understand the mechanisms that regulate length at the molecular level. The prevailing protein-counting model for regulating telomerase access to elongate the telomere does not explain accumulating evidence of a role of DNA replication in telomere length regulation. Here I present an alternative model: the replication fork model that can explain how passage of a replication fork and regulation of origin firing affect telomere length. PMID:27401551

  9. Far field diffraction of an optical vortex beam by a fork-shaped grating

    NASA Astrophysics Data System (ADS)

    Stoyanov, Lyubomir; Topuzoski, Suzana; Stefanov, Ivan; Janicijevic, Ljiljana; Dreischuh, Alexander

    2015-09-01

    In this work we report experimental data confirming the analytically predicted transformation of the topological charge (TC) of an input optical vortex (OV) beam, generated by means of fork-shaped binary computer-generated hologram (CGH), after a second fork-shaped binary CGH. The final TC of the vortex is confirmed to be equal to the TC of the incident beam plus the diffraction order (with its sign) times the TC encoded in the binary grating. The radii of the transformed OVs in the far field also are found to agree fairly well with these predicted by the analytical theory.

  10. Fluvial sediment in Salem Fork watershed, West Virginia

    USGS Publications Warehouse

    Flint, R.F.

    1972-01-01

    Suspended sediment discharged from the 8.32-square-mile Salem Fork study area in Harrison County, W. Va., averaged 3,500 tons per year during the first 4-year period of investigation and 1,770 tons per year during the second 4-year period. The difference as attributed to increased flow control, effected by the completion of detention structures and other conservation measures, the absence of appreciable sediment-producing construction activities, and a reduction of the amounts of rainfall and runoff during the second 4-year period. Particle-size distribution of the suspended sediment discharged from the watershed remained unchanged during the two 4-year periods. Although sand and some silt were deposited in upstream reservoirs, sands and other sediments were evidently entrained in the flow below the reservoirs. During the 7.75-year period, reservoir 11A had a trap efficiency of 88 percent. The average annual sediment yield of subwatershed 11A was 1.31 tons per acre, or 837 tons per square mile. Outflow from reservoir 11A occurred during 81 percent of the investigation 'period, October 1954 to June 1962, and 78 percent of the sediment discharge from the reservoir occurred during less than 6 percent of the investigation period. A comparison of particle-size distribution of inflow sediment with that of outflow sediment revealed that practically all sands and some silts entering reservoir 11A were deposited in the reservoir. Chemical analyses of inflow water and the particle-size analyses suggested that flocculation of fine sediments occurred in the reservoir. Analysis of the sediment data collected at the outflow of reservoir 9 during 1956-62 revealed that the average annual sediment discharge was 128,000 pounds per year. Limited particle-size data suggested that practically no sand was discharged from reservoir 9, even though the inflow contained sand. Average annual inflow to reservoirs 11A and 9 compared favorably with average annual runoff for the entire watershed

  11. Time of travel of solutes in the East Fork Trinity River, November 1975; and Elm Fork Trinity River, December 1975; Trinity River Basin, Texas

    USGS Publications Warehouse

    Myers, Dennis R.; Slade, Raymond M., Jr.

    1976-01-01

    The U.S. Geological Survey, in cooperation with the North Central Texas Council of Governments, the Trinity River Authority of Texas, and the Texas Water Development Board, conducted two time-of-travel studies in the Trinity River basin in November and December, 1975.  Field data were collected on the East Fork Trinity River during November 18-22, 1975, and on the Elm Fork Trinity River during December 8-13, 1975.  The purpose of these two studies was to provide data that could be used by the Trinity River Authority and the Texas Water Quality Board in the development of a mathematical water-quality model of the two streams.  The model is to be used in a comprehensive water-quality management plan for the Trinity River basin.

  12. EEPD1 Rescues Stressed Replication Forks and Maintains Genome Stability by Promoting End Resection and Homologous Recombination Repair

    PubMed Central

    Wu, Yuehan; Lee, Suk-Hee; Williamson, Elizabeth A.; Reinert, Brian L.; Cho, Ju Hwan; Xia, Fen; Jaiswal, Aruna Shanker; Srinivasan, Gayathri; Patel, Bhavita; Brantley, Alexis; Zhou, Daohong; Shao, Lijian; Pathak, Rupak; Hauer-Jensen, Martin; Singh, Sudha; Kong, Kimi; Wu, Xaiohua; Kim, Hyun-Suk; Beissbarth, Timothy; Gaedcke, Jochen; Burma, Sandeep; Nickoloff, Jac A.; Hromas, Robert A.

    2015-01-01

    Replication fork stalling and collapse is a major source of genome instability leading to neoplastic transformation or cell death. Such stressed replication forks can be conservatively repaired and restarted using homologous recombination (HR) or non-conservatively repaired using micro-homology mediated end joining (MMEJ). HR repair of stressed forks is initiated by 5’ end resection near the fork junction, which permits 3’ single strand invasion of a homologous template for fork restart. This 5’ end resection also prevents classical non-homologous end-joining (cNHEJ), a competing pathway for DNA double-strand break (DSB) repair. Unopposed NHEJ can cause genome instability during replication stress by abnormally fusing free double strand ends that occur as unstable replication fork repair intermediates. We show here that the previously uncharacterized Exonuclease/Endonuclease/Phosphatase Domain-1 (EEPD1) protein is required for initiating repair and restart of stalled forks. EEPD1 is recruited to stalled forks, enhances 5’ DNA end resection, and promotes restart of stalled forks. Interestingly, EEPD1 directs DSB repair away from cNHEJ, and also away from MMEJ, which requires limited end resection for initiation. EEPD1 is also required for proper ATR and CHK1 phosphorylation, and formation of gamma-H2AX, RAD51 and phospho-RPA32 foci. Consistent with a direct role in stalled replication fork cleavage, EEPD1 is a 5’ overhang nuclease in an obligate complex with the end resection nuclease Exo1 and BLM. EEPD1 depletion causes nuclear and cytogenetic defects, which are made worse by replication stress. Depleting 53BP1, which slows cNHEJ, fully rescues the nuclear and cytogenetic abnormalities seen with EEPD1 depletion. These data demonstrate that genome stability during replication stress is maintained by EEPD1, which initiates HR and inhibits cNHEJ and MMEJ. PMID:26684013

  13. Channelization and floodplain forests: Impacts of accelerated sedimentation and valley plug formation on floodplain forests of the Middle Fork Forked Deer River, Tennessee, USA

    USGS Publications Warehouse

    Oswalt, S.N.; King, S.L.

    2005-01-01

    We evaluated the severe degradation of floodplain habitats resulting from channelization and concomitant excessive coarse sedimentation on the Middle Fork Forked Deer River in west Tennessee from 2000 to 2003. Land use practices have resulted in excessive sediment in the tributaries and river system eventually resulting in sand deposition on the floodplain, increased overbank flooding, a rise in the groundwater table, and ponding of upstream timber. Our objectives were to: (1) determine the composition of floodplain vegetation communities along the degraded river reach, (2) to isolate relationships among these communities, geomorphic features, and environmental variables and (3) evaluate successional changes based on current stand conditions. Vegetation communities were not specifically associated with predefined geomorphic features; nevertheless, hydrologic and geomorphic processes as a result of channelization have clearly affected vegetation communities. The presence of valley plugs and continued degradation of upstream reaches and tributaries on the impacted study reach has arrested recovery of floodplain plant communities. Historically common species like Liquidambar styraciflua L. and Quercus spp. L. were not important, with importance values (IV) less than 1, and occurred in less than 20% of forested plots, while Acer rubrum L., a disturbance-tolerant species, was the most important species on the site (IV = 78.1) and occurred in 87% of forested plots. The results of this study also indicate that channelization impacts on the Middle Fork Forked Deer River are more temporally and spatially complex than previously described for other river systems. Rehabilitation of this system necessitates a long-term, landscape-scale solution that addresses watershed rehabilitation in a spatially and temporally hierarchical manner. ?? 2005 Elsevier B.V. All rights reserved.

  14. Recent sedimentation and surface-water flow patterns on the flood plain of the North Fork Forked Deer River, Dyer County, Tennessee

    USGS Publications Warehouse

    Wolfe, W.J.; Diehl, T.H.

    1993-01-01

    Sedimentation in the 19th and 20th centuries has had a major effect on surface-water drainage conditions along a 7-mile section of the North, Fork Forked Deer River flood plain, Dyer County, Tenn. During the century prior to 1930, 5 to 12 feet of sediment were deposited over much of the flood plain, resulting in channel obstruction and widespread flooding. The estimated bankfull capacity of the natural channel before it was channelized in 19 16 was comparable to the base flow of the river during the 1980's. Ditching of the river between 191i6 and 1;9,21 was followed by reductions in sedimentation rates over parts of the flood plain. However, the effects of sedimentation have persisted. Occlusions along the natural channel of the river have divided this stream reach into a series of sloughs. These sloughs continue to fill with sediment and are surrounded by ponds that have expanded since 1941. Degradation of the North Fork Forked Deer ditch may eventually reduce ponding over much of the flood plain. Active incision of headcuts in both banks of the ditch is enhancing the drainage of widespread ponded areas. These headcuts likely will have limited effect on drainage of most tributaries. The highest recent sedimentation rates, in places more than 0.2 foot per year, are concentrated near the flood-plain margin along tributary streams. In conjunction with beaver dams and debris, ongoing sedimentation has blocked flow in several tributaries, posing a flood hazard to agricultural land near the flood-plain margin. The occluded tributaries likely will continue to overflow unless they are periodically dredged or their sediment loads are reduced.

  15. Conservation Practices and Water Quality in the Iowa River's South Fork Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Iowa River’s South Fork drains 87,000 ha under intensive, high-production agriculture. Corn-soybean rotations occupy about 85% of the watershed. About 100 swine CAFOs generate manure applied onto about a quarter of the watershed annually. Artificial drainage is extensive because the young glacia...

  16. BENZO(A)PYRENE DIOL EPOXIDE I BINDS TO DNA AT REPLICATION FORKS (JOURNAL VERSION)

    EPA Science Inventory

    The distribution in replication forks of DNA lesions caused by the treatment of S phase calls with benzo(a)pyrene-diol-epoxide-1 (BPDE-1) was studied in synchronized C3H10T1/2 cells. Sites of carcinogen modification of DNA were identified by polyclonal rabbit antibodies that were...

  17. CLARK FORK RIVER AND LAKE PEND OREILLE - IDHW-DOE WATER QUALITY STUDY, 1984

    EPA Science Inventory

    Under a cooperative agreement, U.S. Geological Survey technicians have been measuring river flow and suspended sediment loads and collecting water samples for laboratory analysis on a monthly basis since July 1984 for the Clark Fork River and Lake Pend Oreille, Idaho (17010213). ...

  18. SOUTH FORK COEUR D'ALENE RIVER, NORTHERN IDAHO. DISTRIBUTION OF HEAVY METAL LOADINGS

    EPA Science Inventory

    The purpose of this study is to determine the current distribution of metals loadings to the South Fork Coeur dAlene River, Idaho (17010301, 17010303). Water quality and flow data obtained from EPA Region 10 for September 1986 and September 1987 are used to determine loadings du...

  19. Do sister forks of bidirectionally growing replicons proceed at unequal rates

    SciTech Connect

    Dubey, D.D.; Raman, R.

    1987-02-01

    DNA fibre autoradiography in different tissues of the rodents Bandicota bengalensis and Nesokia indica reveals a high frequency of such bidirectionally replicating replicons whose sister hot tracks are of unequal size. These results suggest intrarepliconic difference in the rates of fork migration in the two directions.

  20. Human HLTF mediates postreplication repair by its HIRAN domain-dependent replication fork remodelling

    PubMed Central

    Achar, Yathish Jagadheesh; Balogh, David; Neculai, Dante; Juhasz, Szilvia; Morocz, Monika; Gali, Himabindu; Dhe-Paganon, Sirano; Venclovas, Česlovas; Haracska, Lajos

    2015-01-01

    Defects in the ability to respond properly to an unrepaired DNA lesion blocking replication promote genomic instability and cancer. Human HLTF, implicated in error-free replication of damaged DNA and tumour suppression, exhibits a HIRAN domain, a RING domain, and a SWI/SNF domain facilitating DNA-binding, PCNA-polyubiquitin-ligase, and dsDNA-translocase activities, respectively. Here, we investigate the mechanism of HLTF action with emphasis on its HIRAN domain. We found that in cells HLTF promotes the filling-in of gaps left opposite damaged DNA during replication, and this postreplication repair function depends on its HIRAN domain. Our biochemical assays show that HIRAN domain mutant HLTF proteins retain their ubiquitin ligase, ATPase and dsDNA translocase activities but are impaired in binding to a model replication fork. These data and our structural study indicate that the HIRAN domain recruits HLTF to a stalled replication fork, and it also provides the direction for the movement of the dsDNA translocase motor domain for fork reversal. In more general terms, we suggest functional similarities between the HIRAN, the OB, the HARP2, and other domains found in certain motor proteins, which may explain why only a subset of DNA translocases can carry out fork reversal. PMID:26350214

  1. Human HLTF mediates postreplication repair by its HIRAN domain-dependent replication fork remodelling

    SciTech Connect

    Achar, Yathish Jagadheesh; Balogh, David; Neculai, Dante; Juhasz, Szilvia; Morocz, Monika; Gali, Himabindu; Dhe-Paganon, Sirano; Venclovas, Česlovas; Haracska, Lajos

    2015-09-08

    Defects in the ability to respond properly to an unrepaired DNA lesion blocking replication promote genomic instability and cancer. Human HLTF, implicated in error-free replication of damaged DNA and tumour suppression, exhibits a HIRAN domain, a RING domain, and a SWI/SNF domain facilitating DNA-binding, PCNA-polyubiquitin-ligase, and dsDNA-translocase activities, respectively. Here, we investigate the mechanism of HLTF action with emphasis on its HIRAN domain. We found that in cells HLTF promotes the filling-in of gaps left opposite damaged DNA during replication, and this postreplication repair function depends on its HIRAN domain. Our biochemical assays show that HIRAN domain mutant HLTF proteins retain their ubiquitin ligase, ATPase and dsDNA translocase activities but are impaired in binding to a model replication fork. These data and our structural study indicate that the HIRAN domain recruits HLTF to a stalled replication fork, and it also provides the direction for the movement of the dsDNA translocase motor domain for fork reversal. We suggest functional similarities between the HIRAN, the OB, the HARP2, and other domains found in certain motor proteins, which may explain why only a subset of DNA translocases can carry out fork reversal.

  2. 77 FR 71611 - Land Acquisitions; North Fork Rancheria of Mono Indians of California

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-03

    ... Tribe's current government headquarters, which are located in the town of North Fork, Madera County, California, described as: Real property in the City of UNINCORPORATED AREA, County of Madera, State of..., AND 8 of PARCEL MAP 3426 IN THE UNINCORPORATED AREA OF THE COUNTY OF MADERA, STATE OF CALIFORNIA,...

  3. Inferring Causes of Biological Impairment in the Clear Fork Watershed, West Virginia (Final)

    EPA Science Inventory

    The Clear Fork, WV case study illustrates a causal assessment in a watershed using the USEPA stressor identification process described on www.epa.gov/caddis. This case study demonstrates that a watershed-wide causal assessment has several advantages for making analysis practical,...

  4. Double Moutain Fork Brazos River between Lubbock and Buffalo Lakes, Texas

    USGS Publications Warehouse

    Joerns, J.O.

    1955-01-01

    The purpose of this investigation was to study quantity, quality, and possible sources of the low flow and spring inflow of the Double Mountain Fork of the Brazos River between the Lubbock sewage disposal plant, 3 miles southeast of Lubbock, and a County Road crossing about 15 miles downstream and 4.2 miles northeast of Slaton, Lubbock County (fig. 1).

  5. 77 FR 23059 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for Three Forks...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... Forks springsnail as a candidate for listing on October 30, 2001 (66 FR 54808). We first identified the San Bernardino springsnail as a candidate for listing on December 6, 2007 (72 FR 69034). Candidates... Bernardino springsnail. In our most recent annual Candidate Notice of Review dated November 10, 2010 (75...

  6. Human HLTF mediates postreplication repair by its HIRAN domain-dependent replication fork remodelling.

    PubMed

    Achar, Yathish Jagadheesh; Balogh, David; Neculai, Dante; Juhasz, Szilvia; Morocz, Monika; Gali, Himabindu; Dhe-Paganon, Sirano; Venclovas, Česlovas; Haracska, Lajos

    2015-12-01

    Defects in the ability to respond properly to an unrepaired DNA lesion blocking replication promote genomic instability and cancer. Human HLTF, implicated in error-free replication of damaged DNA and tumour suppression, exhibits a HIRAN domain, a RING domain, and a SWI/SNF domain facilitating DNA-binding, PCNA-polyubiquitin-ligase, and dsDNA-translocase activities, respectively. Here, we investigate the mechanism of HLTF action with emphasis on its HIRAN domain. We found that in cells HLTF promotes the filling-in of gaps left opposite damaged DNA during replication, and this postreplication repair function depends on its HIRAN domain. Our biochemical assays show that HIRAN domain mutant HLTF proteins retain their ubiquitin ligase, ATPase and dsDNA translocase activities but are impaired in binding to a model replication fork. These data and our structural study indicate that the HIRAN domain recruits HLTF to a stalled replication fork, and it also provides the direction for the movement of the dsDNA translocase motor domain for fork reversal. In more general terms, we suggest functional similarities between the HIRAN, the OB, the HARP2, and other domains found in certain motor proteins, which may explain why only a subset of DNA translocases can carry out fork reversal. PMID:26350214

  7. Assessment of the Iowa River's South Fork Watershed: Part 2. Conservation Practices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Assessments of conservation practice effects on water quality in watersheds require the types and extent of practices implemented to be known. This paper assesses results from a conservation-practices inventory for the South Fork of the Iowa River (78,000 ha), conducted in 2005. Agricultural managem...

  8. "Forked Tongue: The Politics of Bilingual Education," by Rosalie Pedalino Porter. Book Review.

    ERIC Educational Resources Information Center

    Amabisca, Anastasia Aimee

    1994-01-01

    Based on personal experience rather than empirical evidence, "Forked Tongue" presents a biased view that could damage the future of bilingual education in the United States. The book considers bilingual education a threat because it prolongs the learning of English and promotes the maintenance of other "un-American" languages that prevent…

  9. Human HLTF mediates postreplication repair by its HIRAN domain-dependent replication fork remodelling

    DOE PAGESBeta

    Achar, Yathish Jagadheesh; Balogh, David; Neculai, Dante; Juhasz, Szilvia; Morocz, Monika; Gali, Himabindu; Dhe-Paganon, Sirano; Venclovas, Česlovas; Haracska, Lajos

    2015-09-08

    Defects in the ability to respond properly to an unrepaired DNA lesion blocking replication promote genomic instability and cancer. Human HLTF, implicated in error-free replication of damaged DNA and tumour suppression, exhibits a HIRAN domain, a RING domain, and a SWI/SNF domain facilitating DNA-binding, PCNA-polyubiquitin-ligase, and dsDNA-translocase activities, respectively. Here, we investigate the mechanism of HLTF action with emphasis on its HIRAN domain. We found that in cells HLTF promotes the filling-in of gaps left opposite damaged DNA during replication, and this postreplication repair function depends on its HIRAN domain. Our biochemical assays show that HIRAN domain mutant HLTF proteinsmore » retain their ubiquitin ligase, ATPase and dsDNA translocase activities but are impaired in binding to a model replication fork. These data and our structural study indicate that the HIRAN domain recruits HLTF to a stalled replication fork, and it also provides the direction for the movement of the dsDNA translocase motor domain for fork reversal. We suggest functional similarities between the HIRAN, the OB, the HARP2, and other domains found in certain motor proteins, which may explain why only a subset of DNA translocases can carry out fork reversal.« less

  10. KOOTENAI, CLARK FORK, PEND OREILLE, AND SPOKANE RIVER BASINS, WATER QUALITY ASSESSMENT, 1976

    EPA Science Inventory

    This report contains a water quality assessment approach which will assist EPA planners, land agencies, and state and local agencies in identifying probably nonpoint sources and determining their effects upon the fishable-swimmable aspect of the Kootenai, Clark Fork-Pend Oreille,...