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Sample records for walker branch watershed

  1. Soils of Walker Branch Watershed

    Energy Technology Data Exchange (ETDEWEB)

    Lietzke, D.A.

    1994-01-01

    The soil survey of Walker Branch Watershed (WBW) utilized the most up-to-date knowledge of soils, geology, and geohydrology in building the soils data base needed to reinterpret past research and to begin new research in the watershed. The soils of WBW were also compared with soils mapped elsewhere along Chestnut Ridge on the Oak Ridge Reservation to (1) establish whether knowledge obtained elsewhere could be used within the watershed, (2) determine whether there were any soils restricted to the watershed, and (3) evaluate geologic formation lateral variability. Soils, surficial geology, and geomorphology were mapped at a scale of 1:1200 using a paper base map having 2-ft contour intervals. Most of the contours seemed to reasonably represent actual landform configurations, except for dense wooded areas. For example, the very large dolines or sinkholes were shown on the contour base map, but numerous smaller ones were not. In addition, small drainageways and gullies were often not shown. These often small but important features were located approximately as soil mapping progressed. WBW is underlain by dolostones of the Knox Group, but only a very small part of the surface area contains outcroppings of rock and most outcrops were located in the lower part. Soil mapping revealed the presence of both ancient alluvium and ancient colluvium deposits, not recognized in previous soil surveys, that have been preserved in high-elevation stable portions of present-day landforms. An erosional geomorphic process of topographic inversion requiring several millions of years within the Pleistocene is necessary to bring about the degree of inversion that is expressed in the watershed. Indeed, some of these ancient alluvial and colluvial remnants may date back into the Tertiary. Also evident in the watershed, and preserved in the broad, nearly level bottoms of dolines, are multiple deposits of silty material either devoid or nearly devoid of coarse fragments. Recent research

  2. Third annual Walker Branch Watershed research symposium. Program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales that is being integrated through large-scale experiments along with computer modeling and graphical interfaces. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. Regional and global issues addressed by presentations include emissions of carbon dioxide, methane, and other hydrocarbons; deposition of sulfate, nitrate, and mercury; land-use changes; biological diversity; droughts; and water quality. The reports presented in this symposium illustrate a wide range of methods and approaches and focus more on concepts and techniques than on a specific physical site. Sites and projects that have contributed research results to this symposium include Walker Branch Watershed (DOE), the Coweeta Hydrologic Laboratory and LTER site (USFS and NSF), Great Smoky Mountains National Park (research funded by NPS, TVA, and EPRI), Imnavait Creek, Alaska (DOE), the TVA-Norris Whole-tree Facility (TVA and EPRI), and DOE`s Biomass Program.

  3. Field studies of streamflow generation using natural and injected tracers on Bickford and Walker Branch Watersheds

    Energy Technology Data Exchange (ETDEWEB)

    Genereux, D.; Hemond, H. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Civil Engineering; Mulholland, P. [Oak Ridge National Lab., TN (United States)

    1992-05-01

    Field studies of streamflow generation were undertaken on two forested watersheds, the West Road subcatchment of Bickford Watershed in central Massachusetts and the West Fork of Walker Branch Watershed in eastern Tennessee. A major component of the research was development of a two-stage methodology for the use of naturally-occurring {sup 222}Rn as a tracer. The first of the two stages was solving a mass-balance equation for {sup 222}Rn around a stream reach of interest in order to calculate Rn{sub q}, the {sup 222}Rn content of the lateral inflow to the reach; a conservative tracer (chloride) and a volatile tracer (propane) were injected into the study stream to account for lateral inflow to, and volatilization from, the study reach. The second stage involved quantitative comparison of Rn{sub q} to the measured {sup 222}Rn concentrations of different subsurface waters in order to assess how important these waters were in contributing lateral inflow to the stream reach.

  4. Mechanisms and rates of atmospheric deposition of selected trace elements and sulfate to a deciduous forest watershed. [Roles of dry and wet deposition concentrations measured in Walker Branch Watershed

    Energy Technology Data Exchange (ETDEWEB)

    Lindberg, S.E.; Harriss, R.C.; Turner, R.R.; Shriner, D.S.; Huff, D.D.

    1979-06-01

    The critical links between anthropogenic emissions to the atmosphere and their effects on ecosystems are the mechanisms and rates of atmospheric deposition. The atmospheric input of several trace elements and sulfate to a deciduous forest canopy is quantified and the major mechanisms of deposition are determined. The study area was Walker Branch Watershed (WBW) in eastern Tennessee. The presence of a significant quantity of fly ash and dispersed soil particles on upward-facing leaf and flat surfaces suggested sedimentation to be a major mechanism of dry deposition to upper canopy elements. The agreement for deposition rates measured to inert, flat surfaces and to leaves was good for Cd, SO/sub 4//sup =/, Zn, and Mn but poor for Pb. The precipitation concentrations of H/sup +/, Pb, Mn, and SO/sub 4//sup =/ reached maximum values during the summer months. About 90% of the wet deposition of Pb and SO/sub 4//sup =/ was attributed to scavenging by in-cloud processes while for Cd and Mn, removal by in-cloud scavenging accounted for 60 to 70% of the deposition. The interception of incoming rain by the forest canopy resulted in a net increase in the concentrations of Cd, Mn, Pb, Zn, and SO/sub 4//sup =/ but a net decrease in the concentration of H/sup +/. The source of these elements in the forest canopy was primarily dry deposited aerosols for Pb, primarily internal plant leaching for Mn, Cd, and Zn, and an approximately equal combination of the two for SO/sub 4//sup =/. Significant fractions of the total annual elemental flux to the forest floor in a representative chestnut oak stand were attributable to external sources for Pb (99%), Zn (44%), Cd (42%), SO/sub 4//sup =/ (39%), and Mn (14%), the remainder being related to internal element cycling mechanisms. On an annual scale the dry deposition process constituted a significant fraction of the total atmospheric input. (ERB)

  5. Walker Branch Throughfall Displacement Experiment Data Report: Site Characterization, System Performance, Weather, Species Composition, and Growth

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, P.J.

    2001-09-04

    This numeric data package provides data sets, and accompanying documentation, on site characterization, system performance, weather, species composition, and growth for the Throughfall Displacement Experiment, which was established in the Walker Branch Watershed of East Tennessee to provide data on the responses of forests to altered precipitation regimes. The specific data sets include soil water content and potential, coarse fraction of the soil profile, litter layer temperature, soil temperature, monthly weather, daily weather, hourly weather, species composition of trees and saplings, mature tree and sapling annual growth, and relative leaf area index. Fortran and SAS{trademark} access codes are provided to read the ASCII data files. The data files and this documentation are available without charge on a variety of media and via the Internet from the Carbon Dioxide Information Analysis Center (CDIAC).

  6. Integrated Modeling System for Analysis of Watershed Water Balance: A Case Study in the Tims Branch Watershed, South Carolina

    Science.gov (United States)

    Setegn, S. G.; Mahmoudi, M.; Lawrence, A.; Duque, N.

    2015-12-01

    The Applied Research Center at Florida International University (ARC-FIU) is supporting the soil and groundwater remediation efforts of the U.S. Department of Energy (DOE) Savannah River Site (SRS) by developing a surface water model to simulate the hydrology and the fate and transport of contaminants and sediment in the Tims Branch watershed. Hydrological models are useful tool in water and land resource development and decision-making for watershed management. Moreover, simulation of hydrological processes improves understanding of the environmental dynamics and helps to manage and protect water resources and the environment. MIKE SHE, an advanced integrated modeling system is used to simulate the hydrological processes of the Tim Branch watershed with the objective of developing an integrated modeling system to improve understanding of the physical, chemical and biological processes within the Tims Branch watershed. MIKE SHE simulates water flow in the entire land based phase of the hydrological cycle from rainfall to river flow, via various flow processes such as, overland flow, infiltration, evapotranspiration, and groundwater flow. In this study a MIKE SHE model is developed and applied to the Tim branch watershed to study the watershed response to storm events and understand the water balance of the watershed under different climatic and catchment characteristics. The preliminary result of the integrated model indicated that variation in the depth of overland flow highly depend on the amount and distribution of rainfall in the watershed. The ultimate goal of this project is to couple the MIKE SHE and MIKE 11 models to integrate the hydrological component in the land phase of hydrological cycle and stream flow process. The coupled MIKE SHE/MIKE 11 model will further be integrated with an Ecolab module to represent a range of water quality, contaminant transport, and ecological processes with respect to the stream, surface water and groundwater in the Tims

  7. Does freezing and dynamic flexing of frozen branches impact the cavitation resistance of Malus domestica and the Populus clone Walker?

    Science.gov (United States)

    Christensen-Dalsgaard, Karen K; Tyree, Melvin T

    2013-11-01

    Frost damage to the xylem conduits of trees is a phenomenon of eco-physiological importance. It is often documented in terms of the percentage loss of conductivity (PLC), an indicator of air filling of the conduits. However, trees that refill their conduits in spring could be impacted more by damage to the conduits that reduce cavitation resistance, making them more susceptible to future drought events. We investigated whether ice formation, dynamic flexing of frozen branches or freeze-thaw events could reduce the cavitation resistance (cause "frost fatigue") in first-year shoots of apple (Malus domestica) and clonal hybrid cottonwood (Walker). Frost fatigue was measured in terms of P50 (the negative xylem pressure required to cause a 50 % loss of conductivity). All treatment groups showed significant frost fatigue, with the exception of the pre-flushed, constantly frozen poplar branches. The P50 following freeze treatments was approximately 50 % of the pre-freeze values. The effect tended to be greater in freeze-thawed branches. Dynamic bending of the branches had no effect on either PLC or P50. In three out of four cases, there was a significant correlation between P50 and PLC. Frost fatigue occurred in both apple and poplar, two unrelated species with different drought and frost tolerances, suggesting that it may be a widespread phenomenon that could impact the ecophysiology of temperate forests.

  8. Transport of contaminants during storms in the White Oak Creek and Melton Branch watersheds

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, D.K.; Marsh, J.D.; Larsen, I.L.; Wickliff, D.S.; Clapp, R.B.

    1991-01-01

    This report documents the transport of contaminants from Solid Waste Storage Area (SWSA) 5 along two principle pathways: the saturated groundwater system and the intermittently saturated storm flow system. The results of the storm flow sampling show a {sup 90}Sr anomaly in SWSA 5 that is suggested by the similar mobility of {sup 3}H and {sup 90}Sr, in spite of the reactive nature of {sup 90}Sr. An empirical relationship between concentration and discharge was established for {sup 3}H and {sup 90}Sr in the Melton Branch Watershed. The relationship is of the form C = AD{sup b}, where C is concentration of either {sup 3}H or {sup 90}Sr, D is discharge at MBS, and A and b are empirical constants. A model was developed and a computer program written to separate the discharge into quick-flow and base flow components. The results of the modeling, using data collected during storm flow, showed that 44% of the annual stream discharge occurred as quick flow, whereas only 16% of the {sup 3}H and 27% of the {sup 90}Sr occurred as quick flow. The data show that for SWSA 5 the saturated groundwater pathway is quite important in dry years, such as the 1988 water year. Data from other areas, such as SWSA 6 suggest that the storm flow pathway may be more important in wet years. This study has several important implications for remedial actions and site monitoring. 23 refs., 52 figs., 2 tabs.

  9. FellWalker - a Clump Identification Algorithm

    CERN Document Server

    Berry, David

    2014-01-01

    This paper describes the FellWalker algorithm, a watershed algorithm that segments a 1-, 2- or 3-dimensional array of data values into a set of disjoint clumps of emission, each containing a single significant peak. Pixels below a nominated constant data level are assumed to be background pixels and are not assigned to any clump. FellWalker is thus equivalent in purpose to the CLUMPFIND algorithm. However, unlike CLUMPFIND, which segments the array on the basis of a set of evenly-spaced contours and thus uses only a small fraction of the available data values, the FellWalker algorithm is based on a gradient-tracing scheme which uses all available data values. Comparisons of CLUMPFIND and FellWalker using a crowded field of artificial Gaussian clumps, all of equal peak value and width, suggest that the results produced by FellWalker are less dependent on specific parameter settings than are those of CLUMPFIND.

  10. Mass-balance modeling of mineral weathering rates and CO2 consumption in the forested, metabasaltic Hauver Branch watershed, Catoctin Mountain, Maryland, USA

    Science.gov (United States)

    Rice, Karen; Price, Jason R.; Szymanski, David W.

    2013-01-01

    Mineral weathering rates and a forest macronutrient uptake stoichiometry were determined for the forested, metabasaltic Hauver Branch watershed in north-central Maryland, USA. Previous studies of Hauver Branch have had an insufficient number of analytes to permit determination of rates of all the minerals involved in chemical weathering, including biomass. More equations in the mass-balance matrix were added using existing mineralogic information. The stoichiometry of a deciduous biomass term was determined using multi-year weekly to biweekly stream-water chemistry for a nearby watershed, which drains relatively unreactive quartzite bedrock.At Hauver Branch, calcite hosts ~38 mol% of the calcium ion (Ca2+) contained in weathering minerals, but its weathering provides ~90% of the stream water Ca2+. This occurs in a landscape with a regolith residence time of more than several Ka (kiloannum). Previous studies indicate that such old regolith does not typically contain dissolving calcite that affects stream Ca2+/Na+ ratios. The relatively high calcite dissolution rate likely reflects dissolution of calcite in fractures of the deep critical zone.Of the carbon dioxide (CO2) consumed by mineral weathering, calcite is responsible for approximately 27%, with the silicate weathering consumption rate far exceeding that of the global average. The chemical weathering of mafic terrains in decaying orogens thus may be capable of influencing global geochemical cycles, and therefore, climate, on geological timescales. Based on carbon-balance calculations, atmospheric-derived sulfuric acid is responsible for approximately 22% of the mineral weathering occurring in the watershed. Our results suggest that rising air temperatures, driven by global warming and resulting in higher precipitation, will cause the rate of chemical weathering in the Hauver Branch watershed to increase until a threshold temperature is reached. Beyond the threshold temperature, increased recharge would

  11. Residence time, chemical and isotopic analysis of nitrate in the groundwater and surface water of a small agricultural watershed in the Coastal Plain, Bucks Branch, Sussex County, Delaware

    Science.gov (United States)

    Clune, John W.; Denver, Judith M.

    2012-01-01

    Nitrate is a common contaminant in groundwater and surface water throughout the Nation, and water-resource managers need more detailed small-scale watershed research to guide conservation efforts aimed at improving water quality. Concentrations of nitrate in Bucks Branch are among the highest in the state of Delaware and a scientific investigation was performed to provide water-quality information to assist with the management of agriculture and water resources. A combination of major-ion chemistry, nitrogen isotopic composition and age-dating techniques was used to estimate the residence time and provide a chemical and isotopic analysis of nitrate in the groundwater in the surficial aquifer of the Bucks Branch watershed in Sussex County, Delaware. The land use was more than 90 percent agricultural and most nitrogen inputs were from manure and fertilizer. The apparent median age of sampled groundwater is 18 years and the estimated residence time of groundwater contributing to the streamflow for the entire Bucks Branch watershed at the outlet is approximately 19 years. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency drinking-water standard of 10 milligrams per liter (as nitrogen) in 60 percent of groundwater samples and 42 percent of surface-water samples. The overall geochemistry in the Bucks Branch watershed indicates that agriculture is the predominant source of nitrate contamination and the observed patterns in major-ion chemistry are similar to those observed in other studies on the Mid-Atlantic Coastal Plain. The pattern of enrichment in nitrogen and oxygen isotopes (δ15N and δ18O) of nitrate in groundwater and surface water indicates there is some loss of nitrate through denitrification, but this process is not sufficient to remove all of the nitrate from groundwater discharging to streams, and concentrations of nitrate in streams remain elevated.

  12. An Assessment of Hydrology, Fluvial Geomorphology, and Stream Ecology in the Cardwell Branch Watershed, Nebraska, 2003-04

    Science.gov (United States)

    Rus, David L.; Dietsch, Benjamin J.; Woodward, Brenda K.; Fry, Beth E.; Wilson, Richard C.

    2007-01-01

    An assessment of the 16.3-square-mile Cardwell Branch watershed characterized the hydrology, fluvial geomorphology, and stream ecology in 2003-04. The study - performed by the U.S. Geological Survey in cooperation with the City of Lincoln, Nebraska, and the Lower Platte South Natural Resources District - focused on the 7.7-square-mile drainage downstream from Yankee Hill Reservoir. Hydrologic and hydraulic models were developed using the Hydrologic Modeling System (HEC-HMS) and River Analysis System (HEC-RAS) of the U.S. Army Corps of Engineers Hydraulic Engineering Center. Estimates of streamflow and water-surface elevation were simulated for 24-hour-duration design rainstorms ranging from a 50-percent frequency to a 0.2-percent frequency. An initial HEC-HMS model was developed using the standardized parameter estimation techniques associated with the Soil Conservation Service curve number technique. An adjusted HEC-HMS model also was developed in which parameters were adjusted in order for the model output to better correspond to peak streamflows estimated from regional regression equations. Comparisons of peak streamflow from the two HEC-HMS models indicate that the initial HEC-HMS model may better agree with the regional regression equations for higher frequency storms, and the adjusted HEC-HMS model may perform more closely to regional regression equations for larger, rarer events. However, a lack of observed streamflow data, coupled with conflicting results from regional regression equations and local high-water marks, introduced considerable uncertainty into the model simulations. Using the HEC-RAS model to estimate water-surface elevations associated with the peak streamflow, the adjusted HEC-HMS model produced average increases in water-surface elevation of 0.2, 1.1, and 1.4 feet for the 50-, 1-, and 0.2-percent-frequency rainstorms, respectively, when compared to the initial HEC-HMS model. Cross-sectional surveys and field assessments conducted between

  13. Rainfall-runoff modeling of the Chapel Branch Creek Watershed using GIS-based rational and SCS-CN methods

    Science.gov (United States)

    Elizabeth N. Mihalik; Norm S. Levine; Devendra M. Amatya

    2008-01-01

    Chapel Branch Creek (CBC), located within the Town of Santee adjacent to Lake Marion in Orangeburg County, SC, is listed on the SC 2004 303(d) list of impaired waterbodies due to elevated levels of nitrogen (N), phosphorus (P), chlorophyll-a, and pH. In this study, using a GIS-based approach, two runoff modeling methods, the Rational and SCS-CN methods, have been...

  14. Three friendly walkers

    Science.gov (United States)

    Jensen, Iwan

    2017-01-01

    More than 15 years ago Guttmann and Vöge (2002 J. Stat. Plan. Inference 101 107), introduced a model of friendly walkers. Since then it has remained unsolved. In this paper we provide the exact solution to a closely allied model which essentially only differs in the boundary conditions. The exact solution is expressed in terms of the reciprocal of the generating function for vicious walkers which is a D-finite function. However, ratios of D-finite functions are inherently not D-finite and in this case we prove that the friendly walkers generating function is the solution to a non-linear differential equation with polynomial coefficients, it is in other words D-algebraic. We find using numerically exact calculations a conjectured expression for the generating function of the original model as a ratio of a D-finite function and the generating function for vicious walkers. We obtain an expression for this D-finite function in terms of a {{}2}{{F}1} hypergeometric function with a rational pullback and its first and second derivatives. Dedicated to Tony Guttmann on the occasion of his 70th birthday.

  15. Minnesota Watersheds

    Data.gov (United States)

    Minnesota Department of Natural Resources — Statewide minor watershed delineations with major/minor watershed identifiers and names for provinces, major watersheds, and basins. Also included are watershed...

  16. Walker circulation in a transient climate

    Science.gov (United States)

    Plesca, Elina; Grützun, Verena; Buehler, Stefan A.

    2016-04-01

    The tropical overturning circulations modulate the heat exchange across the tropics and between the tropics and the poles. The anthropogenic influence on the climate system will affect these circulations, impacting the dynamics of the Earth system. In this work we focus on the Walker circulation. We investigate its temporal and spatial dynamical changes and their link to other climate features, such as surface and sea-surface temperature patterns, El-Niño Southern Oscillation (ENSO), and ocean heat-uptake, both at global and regional scale. In order to determine the impact of anthropogenic climate change on the tropical circulation, we analyze the outputs of 28 general circulation models (GCMs) from the CMIP5 project. We use the experiment with 1% year-1 increase in CO2 concentration from pre-industrial levels to quadrupling of the concentration. Consistent with previous studies (ex. Ma and Xie 2013), we find that for this experiment most GCMs associate a weakening Walker circulation to a warming transient climate. Due to the role of the Walker Pacific cell in the meridional heat and moisture transport across the tropical Pacific and also the connection to ENSO, we find that a weakened Walker circulation correlates with more extreme El-Niño events, although without a change in their frequency. The spatial analysis of the Pacific Walker cell suggests an eastward displacement of the ascending branch, which is consistent with positive SST anomalies over the tropical Pacific and the link of the Pacific Walker cell to ENSO. Recent studies (ex. England et al. 2014) have linked a strengthened Walker circulation to stronger ocean heat uptake, especially in the western Pacific. The inter-model comparison of the correlation between Walker circulation intensity and ocean heat uptake does not convey a robust response for the investigated experiment. However, there is some evidence that a stronger weakening of the Walker circulation is linked to a higher transient climate

  17. Conformal Patterson-Walker metrics

    CERN Document Server

    Hammerl, Matthias; Šilhan, Josef; Taghavi-Chabert, Arman; Žádník, Vojtěch

    2016-01-01

    The classical Patterson-Walker construction of a split-signature (pseudo-)Riemannian structure from a given torsion-free affine connection is generalized to a construction of a split-signature conformal structure from a given projective class of connections. A characterization of the induced structures is obtained. We achieve a complete description of Einstein metrics in the conformal class formed by the Patterson-Walker metric. Finally, we describe all symmetries of the conformal Patterson-Walker metric. In both cases we obtain descriptions in terms of geometric data on the original structure.

  18. Fall prevention walker during rehabilitation

    Science.gov (United States)

    Tee, Kian Sek; E, Chun Zhi; Saim, Hashim; Zakaria, Wan Nurshazwani Wan; Khialdin, Safinaz Binti Mohd; Isa, Hazlita; Awad, M. I.; Soon, Chin Fhong

    2017-09-01

    This paper proposes on the design of a walker for the prevention of falling among elderlies or patients during rehabilitation whenever they use a walker to assist them. Fall happens due to impaired balance or gait problem. The assistive device is designed by applying stability concept and an accelerometric fall detection system is included. The accelerometric fall detection system acts as an alerting device that acquires body accelerometric data and detect fall. Recorded accelerometric data could be useful for further assessment. Structural strength of the walker was verified via iterations of simulation using finite element analysis, before being fabricated. Experiments were conducted to identify the fall patterns using accelerometric data. The design process and detection of fall pattern demonstrates the design of a walker that could support the user without fail and alerts the helper, thus salvaging the users from injuries due to fall and unattended situation.

  19. Intelligently Controllable Walker with Magnetorheological Fluid Brake

    Science.gov (United States)

    Kikuchi, Takehito; Tanida, Sosuke; Tanaka, Toshimasa; Kobayashi, Keigo; Mitobe, Kazuhisa

    Caster walkers are supporting frames with casters and wheels. These tools are regularly utilized as life support tools or walking rehabilitation tools in hospitals, nursing homes and individual residences. Users of the walkers can easily move it thanks to its wheels and casters. However falling accidents often happen when it moves without users. The falling accident is very serious problem and one of leading causes of secondary injuries. In the other case, it is hard to move to desired directions if users have imbalance in their motor functions or sensory functions, e.g., hemiplegic patients. To improve safeness and operability of the walkers, we installed compact MR fluid brakes on the wheels and controlled walking speed and direction of the walker. We named this intelligently controllable walker, “i-Walker” and discussed on the control methods and experimental results in this paper. Preliminary trials for direction control of the first-generation of the i-Walker (i-Walker1) are presented. On the basis of the results, we improved the control method and hardware of the i-Walker1, and developed the second-generation (i-Walker2). System description and experimental results of the i-Walker2 are also described. The i-Walker2 has better operability and lower energy consumption than that of the i-Walker1. The line-tracing controller of the i-Walker2 well controls human motions during walking experiments on the target straight line.

  20. Madame Kara Walker, notre artiste

    Directory of Open Access Journals (Sweden)

    Riché Deianne Richardson

    2008-01-01

    Full Text Available « Mon Ennemi, Mon Frère, Mon Bourreau, Mon Amour, » the epic exhibition at ARC/ Musée d’art moderne de la ville de Paris running from 20 June to 9 September, reveals the creative genius and vision of the artist Kara Walker, who was born in Stockton, California in 1969. The show is her most comprehensive one yet in Europe and includes the form that Walker has uniquely developed and for which she is best known, cut-out black silhouettes that are sometimes small and at other times gigantic and r...

  1. Persistence of Hydrologic Variables and Reactive Stream Solute Concentrations in an East Tennessee Watershed

    Energy Technology Data Exchange (ETDEWEB)

    Koirala, Shesh R [ORNL; Gentry, Randall W [ORNL; Mulholland, Patrick J [ORNL; Perfect, Edmund [ORNL; Schwartz, John S [ORNL; Sayler, Gary Steven [ORNL

    2011-01-01

    Time and frequency domain analyses were conducted on weekly time series of water chemistry (nitrate, sulfate and calcium concentrations) collected from November 1995 to December 2005 at the West Fork of Walker Branch in Oak Ridge, Tennessee to evaluate the extent of their persistence and the relationship of this persistence to discharge and rainfall. In this study, spectral and wavelet analyses provided a theoretical basis for insights into long-term water chemistry behavior. All water chemistry parameters showed some level of persistence that was influenced by rainfall and/or discharge. Short-term persistence (less than a year) was related to the persistence of rainfall and discharge, whereas long-term persistence (more than a year) was related to the persistence of discharge. The Walker Branch conceptual hydrology model is augmented by these results that relate characteristic periodicities with flowpaths through different zones: the vadose zone (< 20 week period), saturated zone (20-50 week period) and bedrock zone (> 50 week period) with implications for reactive chemistries within the watershed. (C) 2011 Elsevier B.V. All rights reserved.

  2. Flash Flood Risk Mapping for the Watershed of South Branch of Censhui River%涔水南支小流域山洪风险图编制

    Institute of Scientific and Technical Information of China (English)

    李昌志; 王帆; 黄金池; 何晓燕

    2013-01-01

    山洪风险图是山丘区洪水防治重要的非工程措施之一。以涔水南支小流域山洪风险图编制为例,从编制思路、危险性评估、易损性评估、风险评估以及风险图绘制等方面,对涔水南支小流域山洪风险图编制试点工作的思路、流程及成果进行分析,提出了山洪风险图编制过程中需要明确重点河(沟)段、重要城镇、集镇和村组(社)等居民点及其重要基础设施;需要合理地确定山洪计算标准;分析方法应当根据资料详细程度和编制目标进行选择;山洪风险指标体系及阈值划分需要概化和有针对性;山洪风险图编制可考虑分级分阶段推进等编制要求。%Flash flood risk map is one of the important nonstructural measures for flash flood prevention and control in mountainous areas. Taking the South Censhui River Watershed as an example, this paper systematical y introduces the approaches, procedures and outputs in the pilot trial from the aspects of mapping methodology, hazard analysis, vulnerability assessment, risk estimation, and risk mapping. The conclusions include: (1) flash flood risk map is composed of a series maps and corresponding information should be highlighted in each type of maps; (2) the object of flash flood risk mapping should be focused on the residential areas (important river reaches, towns, vil ages) and fundamental infrastructures in the watershed; (3) reasonable standards for flash flood hydrological analysis are required for flash flood risk mapping; (4) the selection of method for hazard analysis is based on the level of data details and objectives of flash flood risk mapping; (5) the indexes for flash flood risk and their grading need to be simplified and targeted; and (6) it is practical that flood risk mapping is carried out at different levels by stages.

  3. Thermalization of Fermionic Quantum Walkers

    Science.gov (United States)

    Hamza, Eman; Joye, Alain

    2017-03-01

    We consider the discrete time dynamics of an ensemble of fermionic quantum walkers moving on a finite discrete sample, interacting with a reservoir of infinitely many quantum particles on the one dimensional lattice. The reservoir is given by a fermionic quasifree state, with free discrete dynamics given by the shift, whereas the free dynamics of the non-interacting quantum walkers in the sample is defined by means of a unitary matrix. The reservoir and the sample exchange particles at specific sites by a unitary coupling and we study the discrete dynamics of the coupled system defined by the iteration of the free discrete dynamics acting on the unitary coupling, in a variety of situations. In particular, in absence of correlation within the particles of the reservoir and under natural assumptions on the sample's dynamics, we prove that the one- and two-body reduced density matrices of the sample admit large times limits characterized by the state of the reservoir which are independent of the free dynamics of the quantum walkers and of the coupling strength. Moreover, the corresponding asymptotic density profile in the sample is flat and the correlations of number operators have no structure, a manifestation of thermalization.

  4. Hydrologic data for the Walker River Basin, Nevada and California, water years 2010–14

    Science.gov (United States)

    Pavelko, Michael T.; Orozco, Erin L.

    2015-12-10

    Walker Lake is a threatened and federally protected desert terminal lake in western Nevada. To help protect the desert terminal lake and the surrounding watershed, the Bureau of Reclamation and U.S. Geological Survey have been studying the hydrology of the Walker River Basin in Nevada and California since 2004. Hydrologic data collected for this study during water years 2010 through 2014 included groundwater levels, surface-water discharge, water chemistry, and meteorological data. Groundwater levels were measured in wells, and surface-water discharge was measured in streams, canals, and ditches. Water samples for chemical analyses were collected from wells, streams, springs, and Walker Lake. Chemical analyses included determining physical properties; the concentrations of major ions, nutrients, trace metals, dissolved gases, and radionuclides; and ratios of the stable isotopes of hydrogen and oxygen. Walker Lake water properties and meteorological parameters were monitored from a floating platform on the lake. Data collection methods followed established U.S. Geological Survey guidelines, and all data are stored in the National Water Information System database. All of the data are presented in this report and accessible on the internet, except multiple-depth Walker Lake water-chemistry data, which are available only in this report.

  5. Wet granular walkers and climbers

    Science.gov (United States)

    Khan, Zeina S.; Steinberger, Audrey; Seemann, Ralf; Herminghaus, Stephan

    2012-02-01

    We have observed that when a bidisperse mixture of glass beads is moistened by a fluid and shaken sinusoidally in a vertical container, small clusters of beads take off from the surface of the pile and rapidly climb up the container walls against gravity. These self-organized clus- ters are held together and against the wall by liquid capillary bridges, and are led by one large grain with one or more small grains trailing behind. When similar clusters are placed on a horizontally vibrating substrate they self-align and travel horizontally along the axis of vibration with a ratchet-like motion. We report a detailed experimental study performed for the simplest walker system consisting of one large and one small bead, and present a simple model that accounts for the observed behavior. Reference: Z.S. Khan et al.,New J. Phys 13, 053041 (2011).

  6. COMPUTER ANALYSIS OF ELECTROMOTORIC SWIVEL WALKER MOVEMENT

    Directory of Open Access Journals (Sweden)

    Jozef VARGA

    2016-12-01

    Full Text Available The first mechanical construction of swivel walker is from year 1963 and it was aimed for support movement of people with disabilities. This solution was very difficult and it was main reason for purpose of electromotoric module, which facilitates movement and reduce effort of people with disabilities. Therefore further research in this area are still provided. In this paper trajectory of swivel walker with electromotoric modules is described. To analyze the tilt and trajectory structure of the walker SolidWorks software was implemented.

  7. The chaotic interaction of two walkers

    Science.gov (United States)

    Tadrist, Loic; Samara, Naresh; Schlagheck, Peter; Gilet, Tristan

    2016-11-01

    A droplet bouncing on a vertically vibrated bath may be propelled horizontally by the Faraday waves that it generates at each rebound. This association of a wave and a particle is called a walker. Ten years ago, Yves Couder and co-workers noted that the dynamical encounter of two walkers may lead to either scattered trajectories or orbital motion. In this work, we investigate the interaction of two walkers more systematically. The walkers are launched towards each other with finely controlled initial conditions. Output trajectories are classified in four types: scattering, orbiting, wandering and complex. The interaction appears stochastic: the same set of initial parameters (to the measurement accuracy) can produce different outputs. Our analysis of the underlying chaos provides new insights on the stochastic nature of this experiment. This work is supported by the ARC Quandrops of the Wallonia-Brussels Federation.

  8. Misconceptions in Halliday, Resnick and Walker's textbook

    CERN Document Server

    Berman, M S

    2005-01-01

    Eleven misconceptions involving Relativity, Gravitation and Cosmology are exposed, that appeared in the textbook: Fundamentals of Physics, 7th Edition, by Halliday, Resnick and Walker, Willey, New York (2005), or other companion textbooks.

  9. Watershed District

    Data.gov (United States)

    Kansas Data Access and Support Center — Boundaries show on this map are derived from legal descriptions contained in petitions to the Kansas Secretary of State for the creation or extension of watershed...

  10. Watershed Investigations

    Science.gov (United States)

    Bodzin, Alec; Shive, Louise

    2004-01-01

    Investigating local watersheds presents middle school students with authentic opportunities to engage in inquiry and address questions about their immediate environment. Investigation activities promote learning in an investigations interdisciplinary context as students explore relationships among chemical, biological, physical, geological, and…

  11. Healthy Watersheds Protection

    Science.gov (United States)

    Jump to main content US EPA United States Environmental Protection Agency Search Search Healthy Watersheds Protection (HWP) Share ... live in a watershed — thus watershed condition is important to everyone. Watersheds exist at different geographic scales, ...

  12. Digital elevation model of Walker Lake, West-Central Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Walker Lake lies within a topographically closed basin in west-central Nevada and is the terminus of the Walker River. Accurately determining the bathymetry and...

  13. DNA Walker-Regulated Cancer Cell Growth Inhibition.

    Science.gov (United States)

    Li, Feiran; Cha, Tae-Gon; Pan, Jing; Ozcelikkale, Altug; Han, Bumsoo; Choi, Jong Hyun

    2016-06-16

    We demonstrate a DNAzyme-based walker system as a controlled oligonucleotide drug AS1411 release platform for breast cancer treatment. In this system, AS1411 strands are released from fuel strands as a walker moves along its carbon nanotube track. The release rate and amount of anticancer oligonucleotides are controlled by the walker operation. With a walker system embedded within the collagen extracellular matrix, we show that this drug release system can be used for in situ cancer cell growth inhibition.

  14. Improving the Nomad microscopic walker model

    NARCIS (Netherlands)

    Campanella, M.C.

    2010-01-01

    This paper presents the results of two calibration efforts and improvements of the Nomad microscopic walker model. Each calibration consisted in comparing the outcome of 19 sets of model parameters with results from laboratory experiments. Three different flows were used in the calibrations: bidirec

  15. 75 FR 51178 - Safety Standard for Infant Walkers; Correction

    Science.gov (United States)

    2010-08-19

    ... statements on walkers with parking brakes. DATES: Effective on December 21, 2010. FOR FURTHER INFORMATION.... 1216.2(b)(21)(i), concerning a warning statement for walkers with parking brakes omitted a phrase indicating that the warning is only required for walkers that have parking brakes. The preamble to the...

  16. 78 FR 48301 - Establishment of Class E Airspace; Walker, MN

    Science.gov (United States)

    2013-08-08

    ... Federal Aviation Administration 14 CFR Part 71 Establishment of Class E Airspace; Walker, MN AGENCY... airspace at Walker, MN. Controlled airspace is necessary to accommodate new Area Navigation (RNAV) Standard... Federal Register a notice of proposed rulemaking (NPRM) to establish Class E airspace for the Walker, MN...

  17. Walker Calhoun: Cherokee Song and Dance Man. Interview.

    Science.gov (United States)

    Olson, Ted

    1995-01-01

    Born in 1918, the youngest of 12 children, Walker Calhoun describes growing up on the Cherokee Reservation in North Carolina. The schools turned the Cherokee against their old ways, but Walker learned many old songs and dances from his uncle, Will West. Since retirement, Walker has taught the dances and songs to children. His material has been…

  18. 基于分布式水文模型的山洪预警临界雨量分析--以涔水南支小流域为例%Flash Flood Early-Warning Indicators Based on Distributed Hydrological Model-A Case Study in South Branch of Censhui Watershed

    Institute of Scientific and Technical Information of China (English)

    李昌志; 郭良; 刘昌军; 孙东亚

    2015-01-01

    基于我国山洪灾害雨量预警的需求,介绍了采用分布式水文模型分析临界雨量的基本思路与方法,以湖南省涔水南支小流域为例,探讨了流域内3个典型预警对象动态临界雨量的确定方法并获得了相应成果。分析认为,分布式水文模型可以较为详细地设置流域各部分产流、汇流以及洪水特征,有利于模拟山丘区小流域洪水,是同时分析多个对象临界雨量的有效方法;分析预警地点的预警流量是非常重要的前提和基础,流域汇流时间是非常重要的预警时段,应根据流域特征和防灾对象特点,确定一系列典型的预警时段;流域尺度土壤含水量对临界雨量有重要影响。%Using DHM (Distribution Hydrological Model) technique with detailed sub-basin delineation, this study introduces basic concepts and methods of analyzing warning indicators for flash flood early warning. Taking south branch of Censhui watershed in Hunan Province as an example, 3 typical early warning indicators for flash flood dynamic early warning were investigated. This research il ustrates that detailed watershed characteristics can be modeled in-depth by further delineate the watershed into smal er sub-basins to simulate spatial distribution of various basin parameters. The resulted runoff and flood hydrographs show better accuracy at al 3 early warning stations. It further confirms that time of concentration of a watershed is an important factor to warning rainfal duration, and the antecedent soil moisture condition of the watershed has significant impact to the critical rainfal .

  19. Obituary: Robert Mowbray Walker, 1929-2004

    Science.gov (United States)

    Schoenherr, Neil T.

    2004-12-01

    Robert M. Walker, PhD, Professor of Physics in Arts & Sciences and a faculty fellow of the McDonnell Center for the Space Sciences, died of stomach cancer Thursday, 12 February 2004, in Brussels, Belgium. He was 75. Walker worked on the frontiers of space research for more than four decades. Robert Walker was born in Philadelphia on 6 February 1929. His mother was Dorothy Potter and he considered Roger Potter his father though he was not his biological father. His early years were spent in New York City and in upstate New York. He attended the Bronx High School of Science, earned his BS in physics from Union College and in 1954, he received his PhD in particle physics from Yale University. He subsequently joined the General Electric Laboratory in Schenectady, New York where he studied the radiation effects in solids. His work on defects in irradiated copper is still regarded as the definitive work on the topic. In the early 1960s, Walker's discovery of fossil nuclear particle tracks in minerals was instrumental to new developments in geo-chronology and cosmic ray physics. In particular, his discovery of tracks from nuclei heavier than iron opened a new frontier of cosmic ray physics. He subsequently pioneered the use of plastics to detect and count such nuclei in cosmic ray balloon flights. Beginning in 1966, when he moved to Washington University and became the first McDonnell Professor of Physics, his research interests turned more toward space physics. He was the inaugural director of the McDonnell Center, which was established in 1975 by a gift from aerospace pioneer James S. McDonnell. Walker was a member of the NASA committee that allocated samples of the first returned lunar materials, and his laboratory led the way in deciphering their record of lunar, solar system and galactic evolution. Together with Ghislaine Crozaz and other colleagues, Walker made path breaking laboratory studies of the first moon rocks revealing the history of solar radiation and

  20. FACT. New image parameters based on the watershed-algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Linhoff, Lena; Bruegge, Kai Arno; Buss, Jens [TU Dortmund (Germany). Experimentelle Physik 5b; Collaboration: FACT-Collaboration

    2016-07-01

    FACT, the First G-APD Cherenkov Telescope, is the first imaging atmospheric Cherenkov telescope that is using Geiger-mode avalanche photodiodes (G-APDs) as photo sensors. The raw data produced by this telescope are processed in an analysis chain, which leads to a classification of the primary particle that induce a shower and to an estimation of its energy. One important step in this analysis chain is the parameter extraction from shower images. By the application of a watershed algorithm to the camera image, new parameters are computed. Perceiving the brightness of a pixel as height, a set of pixels can be seen as 'landscape' with hills and valleys. A watershed algorithm groups all pixels to a cluster that belongs to the same hill. From the emerging segmented image, one can find new parameters for later analysis steps, e.g. number of clusters, their shape and containing photon charge. For FACT data, the FellWalker algorithm was chosen from the class of watershed algorithms, because it was designed to work on discrete distributions, in this case the pixels of a camera image. The FellWalker algorithm is implemented in FACT-tools, which provides the low level analysis framework for FACT. This talk will focus on the computation of new, FellWalker based, image parameters, which can be used for the gamma-hadron separation. Additionally, their distributions concerning real and Monte Carlo Data are compared.

  1. "Good-Walker" + QCD dipoles = Hard Diffraction

    CERN Document Server

    Peschanski, R

    1998-01-01

    The Good-Walker mechanism for diffraction is shown to provide a link between total and diffractive structure functions and to be relevant for QCD calculations at small x_{Bj}. For Deep-Inelastic scattering on a small-size target (cf. an onium) the r\\^ ole of Good-Walker ``diffractive eigenstates'' is played by the QCD dipoles appearing in the $1/N_C$ limit of QCD. Hard diffraction is thus related to the QCD tripe-dipole vertex which has been recently identified (and calculated) as being a conformal invariant correlator and/or a closed-string amplitude. An extension to hard diffraction at HERA via $k_T-$factorisation of the proton vertices leads to interesting phenomenology.

  2. Auditory perception of a human walker.

    Science.gov (United States)

    Cottrell, David; Campbell, Megan E J

    2014-01-01

    When one hears footsteps in the hall, one is able to instantly recognise it as a person: this is an everyday example of auditory biological motion perception. Despite the familiarity of this experience, research into this phenomenon is in its infancy compared with visual biological motion perception. Here, two experiments explored sensitivity to, and recognition of, auditory stimuli of biological and nonbiological origin. We hypothesised that the cadence of a walker gives rise to a temporal pattern of impact sounds that facilitates the recognition of human motion from auditory stimuli alone. First a series of detection tasks compared sensitivity with three carefully matched impact sounds: footsteps, a ball bouncing, and drumbeats. Unexpectedly, participants were no more sensitive to footsteps than to impact sounds of nonbiological origin. In the second experiment participants made discriminations between pairs of the same stimuli, in a series of recognition tasks in which the temporal pattern of impact sounds was manipulated to be either that of a walker or the pattern more typical of the source event (a ball bouncing or a drumbeat). Under these conditions, there was evidence that both temporal and nontemporal cues were important in recognising theses stimuli. It is proposed that the interval between footsteps, which reflects a walker's cadence, is a cue for the recognition of the sounds of a human walking.

  3. [Accidents with caterpillar Lonomia obliqua (Walker, 1855). An emerging problem].

    Science.gov (United States)

    Sánchez, Matías N; Mignone Chagas, Mariana A; Casertano, Sergio A; Cavagnaro, Luis E; Peichoto, María E

    2015-01-01

    Lonomia obliqua (Walker, 1855) is a moth from the family Saturniidae, widely distributed in tropical rainforests of South America. In its larval stage (caterpillar) it is characterized by bristles that cover the animal's body. These structures are hard and branched spiny evaginations of the cuticle, underneath which a complex mixture of toxic molecules is stored. When spicules are brought into contact with the skin of people, toxins enter passively through the injury, causing not only local but also systemic poisoning (primarily hemorrhagic manifestations). When the whole animal is accidentally crushed, the insect's chitinous bristles are broken and the venomous secretions penetrate the human skin, reaching the blood circulation. Due to the numerous registered cases of erucism in Southern Brazil, the Butantan Institute has produced an antivenom able to neutralize the deleterious effects produced by contact with L. obliqua caterpillar bristles. In Argentina, these kinds of accidents are rare and restricted to the province of Misiones. Taking into account that to date there is no report in this country about clinical cases submitted to a specific treatment (antivenom), our aim is to communicate here six cases of Lonomia caterpillar-induced bleeding syndrome that were treated in the Hospital SAMIC of Puerto Iguazú (Misiones, Argentina) during 2014 with the antilonomic serum produced in Brazil. It is worthy to note that all patients evolved favorably within the first few hours, and for this reason, the use of this antivenom is recommended to treat the cases of Lonomia erucism in Argentina.

  4. Chaotic Friedmann-Robertson-Walker Cosmology

    CERN Document Server

    Calzetta, E A

    1993-01-01

    We show that the dynamics of a spatially closed Friedmann - Robertson - Walker Universe conformally coupled to a real, free, massive scalar field, is chaotic, for large enough field amplitudes. We do so by proving that this system is integrable under the adiabatic approximation, but that the corresponding KAM tori break up when non adiabatic terms are considered. This finding is confirmed by numerical evaluation of the Lyapunov exponents associated with the system, among other criteria. Chaos sets strong limitations to our ability to predict the value of the field at the Big Crunch, from its given value at the Big Bang. (Figures available on request)

  5. William Walker en Centroamérica

    OpenAIRE

    Medaglia Gómez, Marco Aurelio

    2007-01-01

    La campaña Nacional (1856-1857) tuvo su origen en la presencia de los filibusteros en Nicaragua. William Walker fue el mayor representante de la política del “Destino Manifiesto” de los Estados Unidos a mediados del siglo XIX. Esto se manifiesta en sus incursiones en Baja California y Sonora y más tarde en Nicaragua y sus pretensiones sobre Centroamérica. La llamada “falange americana” encarna los intereses de los estados sureños que pretendían mantener su modelo económico basado en la esclav...

  6. Variante de Dandy Walker: relato de caso = Dandy Walker variant: a case report

    Directory of Open Access Journals (Sweden)

    Khan, Richard Lester et al.

    2009-01-01

    Full Text Available Objetivos: relatar o caso de um paciente com variante de Dandy Walker, chamando atenção para a importância da suspeita, investigação e manejo das repercussões clínicas. Descrição do caso: é relatado o caso de um paciente do sexo masculino, com quadro clínico e radiológico típico da Variante de Dandy Walker. Durante o pré-natal, através de ecografia obstétrica com 23 semanas e 3 dias, apresentou alterações sugestivas de Síndrome de Dandy Walker. Ao nascimento apresentou exame físico com fenda palatina, criptorquidia à direita, hexodactilia em ambos os pés. Apresentava ainda ecocardiograma com forame oval patente e persistência do canal arterial. O diagnóstico foi estabelecido através da ressonância magnética realizada após o nascimento, que evidenciava hipoplasia do vermis cerebelar, alargamento da fossa posterior e leve dilatação ventricular. Conclusões: este artigo procura caracterizar a variante de Dandy Walker, que é uma malformação congênita do sistema nervoso central e é o tipo mais comum da Síndrome de Dandy Walker. Seu fenótipo é variável, devendo-se sempre pesquisar malformações tanto intra quanto extracranianas, visto que o risco de mortalidade pós-natal aumenta quando existe esta associação. O tratamento envolve equipe multidisciplinar e o prognóstico é reservado, variando conforme o fenótipo.

  7. Superdiffusive transport by multivalent molecular walkers moving under load

    CERN Document Server

    Olah, Mark J

    2012-01-01

    We introduce a model for translational molecular motors to demonstrate that a multivalent catalytic walker with flexible, uncoordinated legs can transform the free energy of surface-bound substrate sites into mechanical work and undergo biased, superdiffusive motion, even in opposition to an external load force. The walker in the model lacks any inherent orientation of body or track, and its legs have no chemomechanical coupling other than the passive constraint imposed by their connection to a common body. Yet, under appropriate kinetic conditions the walker's motion is biased in the direction of unvisited sites, which allows the walker to move nearly ballistically away from the origin as long as a local supply of unmodified substrate sites is available. The multivalent random walker model is mathematically formulated as a continuous-time Markov process and is studied numerically. We use Monte Carlo simulations to generate ensemble estimates of the mean squared displacement and mean work done for this non-er...

  8. The escape problem for mortal walkers

    CERN Document Server

    Grebenkov, D S

    2016-01-01

    We introduce and investigate the escape problem for random walkers that may eventually die, decay, bleach, or lose activity during their diffusion towards an escape or reactive region on the boundary of a confining domain. In the case of a first-order kinetics (i.e., exponentially distributed lifetimes), we study the effect of the associated death rate onto the survival probability, the exit probability, and the mean first passage time. We derive the upper and lower bounds and some approximations for these quantities. We reveal three asymptotic regimes of small, intermediate and large death rates. General estimates and asymptotics are compared to several explicit solutions for simple domains, and to numerical simulations. These results allow one to account for stochastic photobleaching of fluorescent tracers in bio-imaging, degradation of mRNA molecules in genetic translation mechanisms, or high mortality rates of spermatozoa in the fertilization process. This is also a mathematical ground for optimizing stor...

  9. Adopt Your Watershed

    Data.gov (United States)

    U.S. Environmental Protection Agency — Adopt Your Watershed is a Website that encourages stewardship of the nation's water resources and serves as a national inventory of local watershed groups and...

  10. Human-robot interaction strategies for walker-assisted locomotion

    CERN Document Server

    Cifuentes, Carlos A

    2016-01-01

    This book presents the development of a new multimodal human-robot interface for testing and validating control strategies applied to robotic walkers for assisting human mobility and gait rehabilitation. The aim is to achieve a closer interaction between the robotic device and the individual, empowering the rehabilitation potential of such devices in clinical applications. A new multimodal human-robot interface for testing and validating control strategies applied to robotic walkers for assisting human mobility and gait rehabilitation is presented. Trends and opportunities for future advances in the field of assistive locomotion via the development of hybrid solutions based on the combination of smart walkers and biomechatronic exoskeletons are also discussed. .

  11. Dandy-Walker Malformation Presenting with Psychological Manifestations

    Directory of Open Access Journals (Sweden)

    Yasodha Maheshi Rohanachandra

    2016-01-01

    Full Text Available Dandy-Walker malformation, which is a congenital malformation of the cerebellum, is documented in literature to be associated with psychotic symptoms, obsessive compulsive symptoms, mood symptoms, hyperactivity, and impulsive behavior. The pathogenesis of psychiatric symptoms in Dandy-Walker malformation is thought to be due to disruption of the corticocerebellar tracts, resulting in what is known as cerebellar cognitive affective syndrome. We present a case of Dandy-Walker malformation presenting with psychiatric symptoms. This case highlights the necessity to be aware of psychiatric manifestations of cerebellar disease as it has an impact on the diagnosis and treatment.

  12. 78 FR 25234 - Proposed Establishment of Class E Airspace; Walker, MN

    Science.gov (United States)

    2013-04-30

    ... Federal Aviation Administration 14 CFR Part 71 Proposed Establishment of Class E Airspace; Walker, MN...: This action proposes to establish Class E airspace at Walker, MN. Controlled airspace is necessary to... radius to accommodate new standard instrument approach procedures at Walker Municipal Airport, Walker, MN...

  13. Parcels and Land Ownership, Published in 2011, Walker County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Parcels and Land Ownership dataset as of 2011. The extent of these data is generally Walker County, TX. This metadata was auto-generated through the Ramona GIS...

  14. Interaction of two walkers: wave-mediated energy and force.

    Science.gov (United States)

    Borghesi, Christian; Moukhtar, Julien; Labousse, Matthieu; Eddi, Antonin; Fort, Emmanuel; Couder, Yves

    2014-12-01

    A bouncing droplet, self-propelled by its interaction with the waves it generates, forms a classical wave-particle association called a "walker." Previous works have demonstrated that the dynamics of a single walker is driven by its global surface wave field that retains information on its past trajectory. Here we investigate the energy stored in this wave field for two coupled walkers and how it conveys an interaction between them. For this purpose, we characterize experimentally the "promenade modes" where two walkers are bound and propagate together. Their possible binding distances take discrete values, and the velocity of the pair depends on their mutual binding. The mean parallel motion can be either rectilinear or oscillating. The experimental results are recovered analytically with a simple theoretical framework. A relation between the kinetic energy of the droplets and the total energy of the standing waves is established.

  15. Dandy-Walker variant associated with bipolar affective disorder

    Directory of Open Access Journals (Sweden)

    Anand Lingeswaran

    2009-01-01

    Full Text Available The Dandy-Walker malformation is a congenital brain malformation, typically involving the fourth ventricle and the cerebellum. To date, the Dandy-Walker syndrome has not been described in association with bipolar disorder type I mania, and therefore we briefly report the case of a Dandy-Walker variant associated with acute mania. A 10-year-old boy was brought by his mother to the outpatient clinic of the Department of Psychiatry of a tertiary care hospital, with symptoms of mania. The MRI brain of the patient showed a posterior fossa cystic lesion, a giant cisterna magna communicating with the fourth ventricle and mild hypoplasia of the cerebellar vermis, with the rest of the structures being normal and no signs of hydrocephalus. These findings showed that the patient had a Dandy-Walker variant. He responded partially to valproate and olanzepine, which controlled the acute manic symptoms in the ward.

  16. DANDY-WALKER MALFORMATION: A RARE CONGENITAL ANOMALY

    Directory of Open Access Journals (Sweden)

    Uroos

    2014-08-01

    Full Text Available Dandy Walker Malformation (DWM is a congenital malformation involving the cerebellum and fluid filled spaces around it. A key feature of this syndrome is partial or complete absence of a part of brain located between two cerebellar hemispheres ie. cerebellar vermis.(1 Dandy walker malformation was originally described in 1887 by Sutton and further characterized by Dandy and Blackfan in 1914 followed by Tagart and Walker in 1942. Benda finally labeled this disease as Dandy Walker in 1954. (2 Since the original description, additional studies have reported on various morphological features of this syndrome. It is a genetically sporadic disorder that occurs one in every 30,000live births. (3 Because of its rarity, here we report a case of DWM, in a fetus in which the diagnosis was made prenatally on USG. Later on, MTP was done by expulsion. Fetus was sent for autopsy to rule out other associated congenital abnormalities

  17. Lonomia obliqua Walker (Lepidoptera: Saturniidae: hemostasis implications

    Directory of Open Access Journals (Sweden)

    Silviane Maggi

    2015-06-01

    Full Text Available Summary In southern Brazil, since 1989, several cases of accidents produced by unwilling contact with the body of poisonous caterpillars of the moth species Lonomia obliqua Walker, 1855 (Lepidoptera: Saturniidae, were described. L. obliqua caterpillars have gregarious behavior and feed on leaves of host trees during the night, staying grouped in the trunk during the day, which favors the occurrence of accidents with the species. This caterpillar has the body covered with bristles that on contact with the skin of individuals, breaks and release their contents, inoculating the venom into the victim. The basic constitution of the venom is protein and its components produce physiological changes in the victim, which include disturbances in hemostasis. Hemorrhagic syndrome associated with consumption coagulopathy, intravascular hemolysis and acute renal failure are some of the possible clinical manifestations related to poisoning by L. obliqua. Specific laboratory tests for diagnosis of poisoning have not been described previously. The diagnosis of poisoning is made based on the patient's medical history, clinical manifestations, erythrocyte levels, and, primarily, parameters that evaluate blood coagulation. Treatment is performed with the use of supportive care and the administration of specific hyperimmune antivenom. Poisoning can be serious and even fatal.

  18. ACADEMIC TRAINING (R.P. Walker)

    CERN Multimedia

    Françoise Benz

    2002-01-01

    15, 16, 17 May LECTURE SERIES from 11.00 to 12.00 hrs - Council room, bldg. 503 on 15 May, Auditorium, bldg. 500 on 16 and 17 May Introduction to free electron lasers by R.P. Walker / Rutherford Laboratory, UK The Free-electron laser (FEL) is a source of coherent electromagnetic radiation based on a relativistic electron beam. First operated 25 years ago, the FEL has now reached a stage of maturity for operation in the infra-red region of the spectrum and several facilities provide intense FEL radiation beams for research covering a wide range of disciplines. Several projects both underway and proposed aim at pushing the minimum wavelength from its present limit around 100 nm progressively down to the 1 Angstrom region where the X-ray FEL would open up many new and exciting research possibilities. Other developments aim at increasing power levels to the 10's of kW level. In this series of lectures we give an introduction to the basic principles of FELs and their different modes of operation, and summarise the...

  19. Neurodevelopment in preschool idiopathic toe-walkers.

    Science.gov (United States)

    Martín-Casas, P; Ballestero-Pérez, R; Meneses-Monroy, A; Beneit-Montesinos, J V; Atín-Arratibel, M A; Portellano-Pérez, J A

    2017-09-01

    Idiopathic toe walking, a differential diagnosis for neurological and orthopaedic disorders, has been associated with neurodevelopmental alterations. Neurodevelopmental assessment at early ages using specific tests may improve management and follow-up of these patients. The aim of our study is to analyse the neurodevelopmental characteristics of preschool idiopathic toe-walkers (ITW) by comparing them to a control group. Our descriptive cross-sectional study compared possible risk factors, neurodevelopmental characteristics, and scores on the Child Neuropsychological Maturity Questionnaire (CUMANIN) between a group of 56 ITWs aged 3 to 6 and a control group including 40 children. The proportion of males was significantly higher in the ITW group (P=.008). The percentage of patients with a family history (P=.000) and biological risk factors during the perinatal period (P=.032) was also higher in this group. According to the parents' reports, motor coordination in ITWs was significantly poorer (59%; P=.009). ITWs scored significantly lower on CUMANIN subscales of psychomotricity (=0,001) and memory (P=.001), as well as in verbal development (P=.000), non-verbal development (P=.026), and overall development (P=.004). Foot preference was less marked in the ITW group (P=.047). The neurodevelopmental characteristics of our sample suggest that idiopathic toe walking is a marker of neurodevelopmental impairment. However, further studies are necessary to confirm these findings. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Mass neutrino oscillations in Robertson-Walker space-time

    Institute of Scientific and Technical Information of China (English)

    Huang Xiu-Ju; Li Ze-Jun; Wang Yong-Jiu

    2006-01-01

    Along the geodesic we calculate the interference phase of the mass neutrinos propagating in the radial direction in Robertson-Walker space-time. Since our universe is expanding, the phase factor Φ is increasing under the condition of the same proper physical distance l. Different values of curvature parameter k in Robertson-Walker metric represent different cosmological models, correspondingly, we obtain the different interference phases.

  1. Watershed Boundaries - Watershed Boundary Database for Montana

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This data set is a complete digital hydrologic unit boundary layer of the Subbasins (8-digit), Watersheds (10-digit), and Subwatersheds (12-digit) for Montana. This...

  2. Developing a Watershed Challenge

    Science.gov (United States)

    Roman, Harry T.

    2010-01-01

    This article presents a watershed challenge that gives students an opportunity to investigate the challenge of using a watershed area as a site for development, examining the many aspects of this multifaceted problem. This design challenge could work well in a team-based format, with students taking on specific aspects of the challenges and…

  3. Watersheds in disordered media

    CERN Document Server

    Araújo, N A M; Herrmann, H J; Andrade, J S

    2014-01-01

    What is the best way to divide a rugged landscape? Since ancient times, watersheds separating adjacent water systems that flow, for example, toward different seas, have been used to delimit boundaries. Interestingly, serious and even tense border disputes between countries have relied on the subtle geometrical properties of these tortuous lines. For instance, slight and even anthropogenic modifications of landscapes can produce large changes in a watershed, and the effects can be highly nonlocal. Although the watershed concept arises naturally in geomorphology, where it plays a fundamental role in water management, landslide, and flood prevention, it also has important applications in seemingly unrelated fields such as image processing and medicine. Despite the far-reaching consequences of the scaling properties on watershed-related hydrological and political issues, it was only recently that a more profound and revealing connection has been disclosed between the concept of watershed and statistical physics o...

  4. Walker-Warburg syndrome: a report of 3 cases.

    Science.gov (United States)

    Denis, D; Gambarelli, D; Luciani, A; Aymé, S; Philip, N; Saracco, J B

    1993-01-01

    Walker-Warburg syndrome is a congenital malformation syndrome of unknown etiology which is characterized by fatal neurological lesions. It was first described by Walker in 1942 as involving agyria, hydrocephalus and eye malformations. Its etiology has been discussed in all of the articles on the subject in the literature, but the majority of the authors describe it as an autosomal recessive syndrome. Ultrasonography plays a key role in detecting a cephalic anomaly by prenatal diagnosis as in our 2 cases. The aim of this article is to report 3 new cases of Walker-Warburg syndrome in two families. Knowledge of this syndrome emphasizes both the need for ultrasonographic observation and genetic counselling for families at risk.

  5. Twentieth century Walker Circulation change: data analysis and model experiments

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qingjia [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Chinese Research Academy of Environmental Sciences, River and Coastal Environment Research Center, Beijing (China); Chinese Academy of Sciences, Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Qingdao (China); Latif, Mojib; Park, Wonsun; Keenlyside, Noel S.; Martin, Thomas [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Semenov, Vladimir A. [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); A.M. Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, Moscow (Russian Federation)

    2012-05-15

    Recent studies indicate a weakening of the Walker Circulation during the twentieth century. Here, we present evidence from an atmospheric general circulation model (AGCM) forced by the history of observed sea surface temperature (SST) that the Walker Circulation may have intensified rather than weakened. Observed Equatorial Indo-Pacific Sector SST since 1870 exhibited a zonally asymmetric evolution: While the eastern part of the Equatorial Pacific showed only a weak warming, or even cooling in one SST dataset, the western part and the Equatorial Indian Ocean exhibited a rather strong warming. This has resulted in an increase of the SST gradient between the Maritime Continent and the eastern part of the Equatorial Pacific, one driving force of the Walker Circulation. The ensemble experiments with the AGCM, with and without time-varying external forcing, suggest that the enhancement of the SST gradient drove an anomalous atmospheric circulation, with an enhancement of both Walker and Hadley Circulation. Anomalously strong precipitation is simulated over the Indian Ocean and anomalously weak precipitation over the western Pacific, with corresponding changes in the surface wind pattern. Some sensitivity to the forcing SST, however, is noticed. The analysis of twentieth century integrations with global climate models driven with observed radiative forcing obtained from the Coupled Model Intercomparison Project (CMIP) database support the link between the SST gradient and Walker Circulation strength. Furthermore, control integrations with the CMIP models indicate the existence of strong internal variability on centennial timescales. The results suggest that a radiatively forced signal in the Walker Circulation during the twentieth century may have been too weak to be detectable. (orig.)

  6. ENSO impacts on the South American rainfall during 1980s: Hadley and Walker circulation

    Energy Technology Data Exchange (ETDEWEB)

    De Souza, E.B.; Ambrizzi, T. [Departamento de Ciencias Atmosfericas, Instituto Astronomico y Geofisico, Sao Paulo, SP (Brazil)

    2002-04-01

    The changes in the Hadley and Walter cells and their respective impacts on the South American rainfall during the ENSO episodes observed in the decade of 80, were investigated through cross-sections analyses of the atmospheric circulation in altitude, averaged in the zonal and meridional planes. Such large-scale cells almost inverted their climatological circulation pattern, during El Nino events (1982-83 and 1986-87). In these years, manifestation of the anomalous descending branch of the Hadley and Walker cells affects most of the north-northeast of South America, which inhibited the convective activity associated to the Inter Tropical Convergence Zone (ITCZ) and caused drought conditions in the rainy seasons of the Guyana, Surinam, French Guyana, center-east of the Amazon and most of the Northeast Brazil. On the other hand, conditions of excess of precipitation observed in the south-southeast of South America, were favored by the anomalous ascending branch of the Hadley cell. During La Nina events (1984-85 and 1988-89), it was observed an intensification of the ascending and descending branches associated to the Walker and Hadley cells. The anomalous large-scale ascending movement associated to these cells, was extended to the Northeast of Brazil and equatorial South Atlantic, favoring ITCZ to become more active than the normal, which resulted in an above normal rainy season in these areas. An intense subsidence was noticed in the mid latitudes of South America, which inhibited the large-scale convection in the region, explaining the deficient rainy season observed in most of the south-southeast of South America. [Spanish] Los cambios en las celulas de Hadley y Walker y sus respectivos impactos en Suramerica, en las lluvias, durante los episodios en ENOS, observados en la decada de los 80, son investigados a traves de analisis de reacciones cruzadas de la circulacion atmosferica en altitudes promediadas en planos zonal y meridional. Tales celulas de gran escala

  7. Casimir densities for a boundary in Robertson-Walker spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Saharian, A.A., E-mail: saharian@ictp.i [Department of Physics, Yerevan State University, 1 Alex Manoogian Street, 0025 Yerevan (Armenia); Setare, M.R., E-mail: rezakord@ipm.i [Department of Science of Bijar, University of Kurdistan, Bijar (Iran, Islamic Republic of)

    2010-04-12

    For scalar and electromagnetic fields we evaluate the vacuum expectation value of the energy-momentum tensor induced by a curved boundary in the Robertson-Walker spacetime with negative spatial curvature. In order to generate the vacuum densities we use the conformal relation between the Robertson-Walker and Rindler spacetimes and the corresponding results for a plate moving by uniform proper acceleration through the Fulling-Rindler vacuum. For the general case of the scale factor the vacuum energy-momentum tensor is presented as the sum of the boundary free and boundary induced parts.

  8. Dandy-Walker anomaly in Meckel-Gruber syndrome.

    Science.gov (United States)

    Cincinnati, P; Neri, M E; Valentini, A

    2000-01-01

    We report a fetus affected by Meckel-Gruber syndrome whose phenotype was characterized by macrocephaly, frontal bossing, a saddle nose, marked micrognathia, a distended abdomen, omphalocele, post-axial polydactyly and talipes equinovarus. The main neuropathological finding at autopsy was in a very large cyst located in an abnormally wide posterior cranial fossa consistent with a Dandy-Walker anomaly. Intestinal malrotation, enlarged cystic dysplastic kidneys and hepatic portal fibrosis coexisted. The occurrence of a Dandy-Walker malformation in Meckel-Gruber syndrome confirms a disturbance in rhombencephalon development. Although uncommon, it should be included among the central nervous anomalies representative of the syndrome.

  9. Relative roles of differential SST warming, uniform SST warming and land surface warming in determining the Walker circulation changes under global warming

    Science.gov (United States)

    Zhang, Lei; Li, Tim

    2017-02-01

    Most of CMIP5 models projected a weakened Walker circulation in tropical Pacific, but what causes such change is still an open question. By conducting idealized numerical simulations separating the effects of the spatially uniform sea surface temperature (SST) warming, extra land surface warming and differential SST warming, we demonstrate that the weakening of the Walker circulation is attributed to the western North Pacific (WNP) monsoon and South America land effects. The effect of the uniform SST warming is through so-called "richest-get-richer" mechanism. In response to a uniform surface warming, the WNP monsoon is enhanced by competing moisture with other large-scale convective branches. The strengthened WNP monsoon further induces surface westerlies in the equatorial western-central Pacific, weakening the Walker circulation. The increase of the greenhouse gases leads to a larger land surface warming than ocean surface. As a result, a greater thermal contrast occurs between American Continent and equatorial Pacific. The so-induced zonal pressure gradient anomaly forces low-level westerly anomalies over the equatorial eastern Pacific and weakens the Walker circulation. The differential SST warming also plays a role in driving low-level westerly anomalies over tropical Pacific. But such an effect involves a positive air-sea feedback that amplifies the weakening of both east-west SST gradient and Pacific trade winds.

  10. Branched polynomial covering maps

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    1999-01-01

    A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...

  11. Branched polynomial covering maps

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    2002-01-01

    A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...

  12. Biologia de Automeris illustris (Walker (Lepidoptera, Saturniidae, Hemileucinae Biology of Automeris illustris (Walker (Lepidoptera, Saturniidae, Hemileucinae

    Directory of Open Access Journals (Sweden)

    Alexandre Specht

    2006-06-01

    Full Text Available Objetivou-se estudar a biologia de Automeris illustris (Walker, 1855, um hemileucíneo polifitófago considerado praga secundária da eucaliptocultura e cujas lagartas podem provocar erucismo. Os parâmetros biológicos foram obtidos em condições controladas de temperatura: 25 ± 1ºC, UR 70 ± 10% e fotofase de 14 horas, com observações diárias. Foram avaliados, em cada fase de desenvolvimento, aspectos morfológicos e etológicos, duração e viabilidade. Para relacionar as plantas hospedeiras foram reunidos dados de material coletado em campo e já referidos em bibliografia. Nas condições de laboratório observou-se que o ciclo de vida necessitou de aproximadamente 121 dias, cujos períodos médios das fases de ovo, lagarta, pré-pupa, pupa e adulta foram de 10,60; 80,56; 3,58; 19,17 e 7,83 dias, respectivamente. As lagartas passaram por seis ínstares e tiveram uma razão média de crescimento de 1,47. Observou-se um alto grau de polifitofagia sendo relacionadas 51 plantas hospedeiras pertencentes a 28 famílias. O potencial biótico foi estimado em 8.719.556 indivíduos ao ano.This work aimed to study the biology of Automeris illustris (Walker, 1855 which is a polyphytophagous, considered secondary pest of eucalypts culture in wich their caterpillars might cause erucism. The biological parameters were obtained in controlled conditions of temperature: 25 ± 1ºC, UR 70 ± 10% and photofase of 14 hours, with daily observations. On each developmental phase, morphological and ethologic aspects, as well as duration and viability, were evaluated. In order to link the host plants to the insect it were added data of collected material on field and referred in the bibliography. Under laboratory conditions it was observed that the life cycle needed of about 121 days whose mean periods of eggs, caterpillars, pre-pupae, pupae and adult phases were 10.60, 80.56, 3.58, 19.17 and 7.83 days, respectively. The caterpillars passed by six instars with

  13. The role of walkers' needs and expectations in supporting maintenance of attendance at walking groups: a longitudinal multi-perspective study of walkers and walk group leaders.

    Directory of Open Access Journals (Sweden)

    Aikaterini Kassavou

    Full Text Available There is good evidence that when people's needs and expectations regarding behaviour change are met, they are satisfied with that change, and maintain those changes. Despite this, there is a dearth of research on needs and expectations of walkers when initially attending walking groups and whether and how these needs and expectations have been satisfied after a period of attendance. Equally, there is an absence of research on how people who lead these groups understand walkers' needs and walk leaders' actions to address them. The present study was aimed at addressing both of these gaps in the research.Two preliminary thematic analyses were conducted on face-to-face interviews with (a eight walkers when they joined walking groups, five of whom were interviewed three months later, and (b eight walk leaders. A multi-perspective analysis building upon these preliminary analyses identified similarities and differences within the themes that emerged from the interviews with walkers and walk leaders.Walkers indicated that their main needs and expectations when joining walking groups were achieving long-term social and health benefits. At the follow up interviews, walkers indicated that satisfaction with meeting similar others within the groups was the main reason for continued attendance. Their main source of dissatisfaction was not feeling integrated in the existing walking groups. Walk leaders often acknowledged the same reasons for walkers joining and maintaining attendance at walking. However, they tended to attribute dissatisfaction and drop out to uncontrollable environmental factors and/or walkers' personalities. Walk leaders reported a lack of efficacy to effectively address walkers' needs.Interventions to increase retention of walkers should train walk leaders with the skills to help them modify the underlying psychological factors affecting walkers' maintenance at walking groups. This should result in greater retention of walkers in walking

  14. Comparative Analysis of Probabilistic Models for Activity Recognition with an Instrumented Walker

    CERN Document Server

    Omar, Farheen; Truszkowski, Jakub; Poupart, Pascal; Tung, James; Caine, Allen

    2012-01-01

    Rollating walkers are popular mobility aids used by older adults to improve balance control. There is a need to automatically recognize the activities performed by walker users to better understand activity patterns, mobility issues and the context in which falls are more likely to happen. We design and compare several techniques to recognize walker related activities. A comprehensive evaluation with control subjects and walker users from a retirement community is presented.

  15. Segmentation of stochastic images with a stochastic random walker method.

    Science.gov (United States)

    Pätz, Torben; Preusser, Tobias

    2012-05-01

    We present an extension of the random walker segmentation to images with uncertain gray values. Such gray-value uncertainty may result from noise or other imaging artifacts or more general from measurement errors in the image acquisition process. The purpose is to quantify the influence of the gray-value uncertainty onto the result when using random walker segmentation. In random walker segmentation, a weighted graph is built from the image, where the edge weights depend on the image gradient between the pixels. For given seed regions, the probability is evaluated for a random walk on this graph starting at a pixel to end in one of the seed regions. Here, we extend this method to images with uncertain gray values. To this end, we consider the pixel values to be random variables (RVs), thus introducing the notion of stochastic images. We end up with stochastic weights for the graph in random walker segmentation and a stochastic partial differential equation (PDE) that has to be solved. We discretize the RVs and the stochastic PDE by the method of generalized polynomial chaos, combining the recent developments in numerical methods for the discretization of stochastic PDEs and an interactive segmentation algorithm. The resulting algorithm allows for the detection of regions where the segmentation result is highly influenced by the uncertain pixel values. Thus, it gives a reliability estimate for the resulting segmentation, and it furthermore allows determining the probability density function of the segmented object volume.

  16. Construction of calibration pads facility, Walker Field, Grand Junction, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Ward, D.L.

    1978-08-01

    A gamma-ray spectrometer facility was completed at Walker Field Airport, Grand Junction, Colorado, in November 1976. This report describes spectrometers and their calibration, the construction of the spectrometer facility, the radioelement concentrations, procedures for using the facilites, and environmental considerations. (LK)

  17. 75 FR 35265 - Safety Standard for Infant Walkers: Final Rule

    Science.gov (United States)

    2010-06-21

    .../jumping. Occupant retention--intended to prevent entrapment by setting requirements for leg openings. The... force by means of a pulley, rope, and a falling 8-pound weight on a hardwood floor surface. The walker... components are not specified. Variability in the type and size of the pulley, rope type, test table flexure...

  18. Bobble-Head Doll and Dandy-Walker Syndromes

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-10-01

    Full Text Available A female infant with macrocephaly (head circumference >95th%, hydrocephalus, and Dandy-Walker syndrome, who developed horizontal head movements of the 'no-no' type at 1 year of age, is reported from Federal University of Minas Gerais, and other centers in Brazil.

  19. f-symbols in Robertson-Walker space-times

    CERN Document Server

    Popa, F C; Popa, Florian Catalin; Tintareanu-Mircea, Ovidiu

    2004-01-01

    In a Robertson-Walker space-time a spinning particle model is investigated and we show that in a stationary case, there exists a class of new structures called f-symbols which can generate reducible Killing tensors and supersymmetry algebras.

  20. Alice Walker's Womanism Colored in The Color Purple

    Institute of Scientific and Technical Information of China (English)

    蒋慧慧

    2009-01-01

    In her famous novel The Color Purple,Alice Walker's womanism is colored by four kinds of conseiousness-female consciousness,racial consciousness,root-seeking consciousness,and universal consciousness.It is owing to the womanism that the heroine celie grown from an abused woman to an independent selfhood.

  1. A new species of Culcua Walker (Diptera: Stratiomyidae) from Vietnam

    Science.gov (United States)

    A new species of Culcua Walker (Diptera: Stratiomyidae), C. lingafelteri Woodley, new species, is described from northern Vietnam. It is diagnosed relative to other species using the recent revision of the genus by Rozkošný and Kozánek (2007). This is the first species of Culcua reported from Viet...

  2. Selling Out Mothers and Babies by Marsha Walker

    OpenAIRE

    Sandra M., Gossler

    2003-01-01

    The monitoring project reported in Marsha Walker's book, Selling Out Mothers and Babies, offers a qualitative assessment of formula companies' unethical marketing practices in the United States. The book presents extensive documentation on the questionable strategies of formula companies and how they avoid and circumvent recommendations of the International Code of Marketing of Breast Milk Substitutes.

  3. Behavior of Friedmann-Lemaître-Robertson-Walker Singularities

    Science.gov (United States)

    Fernández-Jambrina, L.

    2016-08-01

    In Stoica (Int. J. Theor. Phys. 55, 71-80, 2016) a regularization procedure is suggested for regularizing Big Bang singularities in Friedmann-Lemaître-Robertson-Walker (FLRW) spacetimes. We argue that this procedure is only appliable to one case of Big Bang singularities and does not affect other types of singularities.

  4. Twisted gauge theories in 3D Walker-Wang models

    CERN Document Server

    Wang, Zitao

    2016-01-01

    Three dimensional gauge theories with a discrete gauge group can emerge from spin models as a gapped topological phase with fractional point excitations (gauge charge) and loop excitations (gauge flux). It is known that 3D gauge theories can be "twisted", in the sense that the gauge flux loops can have nontrivial braiding statistics among themselves and such twisted gauge theories are realized in models discovered by Dijkgraaf and Witten. A different framework to systematically construct three dimensional topological phases was proposed by Walker and Wang and a series of examples have been studied. Can the Walker Wang construction be used to realize the topological order in twisted gauge theories? This is not immediately clear because the Walker-Wang construction is based on a loop condensation picture while the Dijkgraaf-Witten theory is based on a membrane condensation picture. In this paper, we show that the answer to this question is Yes, by presenting an explicit construction of the Walker Wang models wh...

  5. A methodology to calibrate pedestrian walker models using multiple objectives

    NARCIS (Netherlands)

    Campanella, M.C.; Daamen, W.; Hoogendoorn, S.P.

    2012-01-01

    The application of walker models to simulate real situations require accuracy in several traffic situations. One strategy to obtain a generic model is to calibrate the parameters in several situations using multiple-objective functions in the optimization process. In this paper, we propose a general

  6. Bathymetry of Walker Lake, West-Central Nevada

    Science.gov (United States)

    Lopes, Thomas J.; Smith, J. LaRue

    2007-01-01

    Walker Lake lies within a topographically closed basin in west-central Nevada and is the terminus of the Walker River. Much of the streamflow in the Walker River is diverted for irrigation, which has contributed to a decline in lake-surface altitude of about 150 feet and an increase in dissolved solids from 2,500 to 16,000 milligrams per liter in Walker Lake since 1882. The increase in salinity threatens the fresh-water ecosystem and survival of the Lahontan cutthroat trout, a species listed as threatened under the Endangered Species Act. Accurately determining the bathymetry and relations between lake-surface altitude, surface area, and storage volume are part of a study to improve the water budget for Walker Lake. This report describes the updated bathymetry of Walker Lake, a comparison of results from this study and a study by Rush in 1970, and an estimate of the 1882 lake-surface altitude. Bathymetry was measured using a single-beam echosounder coupled to a differentially-corrected global positioning system. Lake depth was subtracted from the lake-surface altitude to calculate the altitude of the lake bottom. A Lidar (light detection and ranging) survey and high resolution aerial imagery were used to create digital elevation models around Walker Lake. The altitude of the lake bottom and digital elevation models were merged together to create a single map showing land-surface altitude contours delineating areas that are currently or that were submerged by Walker Lake. Surface area and storage volume for lake-surface altitudes of 3,851.5-4,120 feet were calculated with 3-D surface-analysis software. Walker Lake is oval shaped with a north-south trending long axis. On June 28, 2005, the lake-surface altitude was 3,935.6 feet, maximum depth was 86.3 feet, and the surface area was 32,190 acres. The minimum altitude of the lake bottom from discrete point depths is 3,849.3 feet near the center of Walker Lake. The lake bottom is remarkably smooth except for mounds near

  7. Philip Glass, Scott Walker ja Sigur Ros! / Immo Mihkelson

    Index Scriptorium Estoniae

    Mihkelson, Immo, 1959-

    2007-01-01

    Pimedate Ööde 11. filmifestivali muusikafilme - Austraalia "Glass: Philipi portree 12 osas" (rež. Scott Hicks), Islandi "Sigur Ros kodus" (rež. Dean DeBois), Suurbritannia "Scott Walker: 30 Century Man" (rež. Stephen Kijak)

  8. Finding the Right Formula: Edwin H. Walker Jr

    Science.gov (United States)

    Keels, Crystal L.

    2005-01-01

    Edwin H. Walker Jr earned his doctorate in chemistry at age 27 and has barely looked back. With 13 publications under his belt before coming out of graduate school, he has also given more than 20 poster presentations in national venues, most recently at the American Chemical Society. He can also include securing a half-million-dollar National…

  9. Larval description of Copitarsia incommoda (Walker) (Lepidoptera: Noctuidae)

    Science.gov (United States)

    The last-instar larva of Copitarsia incommoda (Walker) is described for the first time. Specimens in this study were reared from quinoa (Chenopodium quinoa Willd., Chenopodiaceae), Bolivia, La Paz, 4 km S Viacha, Quipaquipani, 3880 m. The larva of Copitarsia incommoda is compared with larvae of Copi...

  10. Philip Glass, Scott Walker ja Sigur Ros! / Immo Mihkelson

    Index Scriptorium Estoniae

    Mihkelson, Immo, 1959-

    2007-01-01

    Pimedate Ööde 11. filmifestivali muusikafilme - Austraalia "Glass: Philipi portree 12 osas" (rež. Scott Hicks), Islandi "Sigur Ros kodus" (rež. Dean DeBois), Suurbritannia "Scott Walker: 30 Century Man" (rež. Stephen Kijak)

  11. An Adaptive Watershed Management Assessment Based on Watershed Investigation Data

    Science.gov (United States)

    Kang, Min Goo; Park, Seung Woo

    2015-05-01

    The aim of this study was to assess the states of watersheds in South Korea and to formulate new measures to improve identified inadequacies. The study focused on the watersheds of the Han River basin and adopted an adaptive watershed management framework. Using data collected during watershed investigation projects, we analyzed the management context of the study basin and identified weaknesses in water use management, flood management, and environmental and ecosystems management in the watersheds. In addition, we conducted an interview survey to obtain experts' opinions on the possible management of watersheds in the future. The results of the assessment show that effective management of the Han River basin requires adaptive watershed management, which includes stakeholders' participation and social learning. Urbanization was the key variable in watershed management of the study basin. The results provide strong guidance for future watershed management and suggest that nonstructural measures are preferred to improve the states of the watersheds and that consistent implementation of the measures can lead to successful watershed management. The results also reveal that governance is essential for adaptive watershed management in the study basin. A special ordinance is necessary to establish governance and aid social learning. Based on the findings, a management process is proposed to support new watershed management practices. The results will be of use to policy makers and practitioners who can implement the measures recommended here in the early stages of adaptive watershed management in the Han River basin. The measures can also be applied to other river basins.

  12. 75 FR 24753 - The Walker Auto Group, Inc., Miamisburg, OH; Notice of Negative Determination Regarding...

    Science.gov (United States)

    2010-05-05

    ... Employment and Training Administration The Walker Auto Group, Inc., Miamisburg, OH; Notice of Negative... TAA petition filed on behalf of workers at The Walker Auto Group, Inc., Miamisburg, Ohio, was based on... Walker Auto Group, Inc., Miamisburg, Ohio, supplies a service (sales and service of Pontiac automobiles...

  13. Stormwater Impaired Watersheds

    Data.gov (United States)

    Vermont Center for Geographic Information — Stormwater impaired watersheds occuring on both the Priority Waters (Part D - Completed TMDL) and 303(d) list of waters (Part A - need TMDL) The Vermont State...

  14. Watershed Restoration Project

    Energy Technology Data Exchange (ETDEWEB)

    Julie Thompson; Betsy Macfarlan

    2007-09-27

    In 2003, the U.S. Department of Energy issued the Eastern Nevada Landscape Coalition (ENLC) funding to implement ecological restoration in Gleason Creek and Smith Valley Watersheds. This project was made possible by congressionally directed funding that was provided through the US Department of Energy, Energy Efficiency and Renewable Energy, Office of the Biomass Program. The Ely District Bureau of Land Management (Ely BLM) manages these watersheds and considers them priority areas within the Ely BLM district. These three entities collaborated to address the issues and concerns of Gleason Creek and Smith Valley and prepared a restoration plan to improve the watersheds’ ecological health and resiliency. The restoration process began with watershed-scale vegetation assessments and state and transition models to focus on restoration sites. Design and implementation of restoration treatments ensued and were completed in January 2007. This report describes the restoration process ENLC undertook from planning to implementation of two watersheds in semi-arid Eastern Nevada.

  15. Watershed Planning Basins

    Data.gov (United States)

    Vermont Center for Geographic Information — The Watershed Planning Basin layer is part of a larger dataset contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  16. Assessment of Bathymetry and Sediment Accumulation of Walker Lake, PA with Multiple Frequency GPR Antennas

    Science.gov (United States)

    Lachhab, A.; Booterbaugh, A.; Beren, M.

    2012-12-01

    Silting within all man-made reservoirs, can be a major problem. Exploring bathymetry with electromagnetic prospection tools is one way to identify the magnitude of sediment accumulation in lakes and reservoirs. In this study, the bathymetry and sediment accumulation of Walker Lake, PA was explored via multi-frequency ground penetrating radar (GPR) surveys. Walker Lake is located on the North Branch Middle Creek, which is a tributary to Middle Creek within the Susquehanna River basin. The technique developed in this study included two antennas positioned on a medium size inflatable boat towed by a 14' flat-bottom Jon Boat. Both 400 and 100 MHz antennas were deployed and sediment thickness and distribution throughout the lake were identified. A total of eighteen transects were taken along the entire length of the lake. A new method with multiple approaches including RADAN 7, GPR Viewer, SAS 9.1.3 and MATLAB was developed to generate three-Dimensional and contour surface of the pre-1971 Topography and bathymetry based on GPR reflection readings. As a result, depth, accumulation and rate of sedimentation in the lake were successfully measured. The lake was found to vary between 0.5 to 9 meters in depth. Sediment accumulation and distribution were calculated from the difference between the surveyed bathymetry and the 1971 pre-existent landscape topography. Sediment was found to accumulate thickest within the old channel of Middle Creek however, the bulk of the sediment volume lied outside this channel. Sediment deposition accumulates mainly upstream near the inlet to the lake and gradually decreases toward the dam inversely proportional to the depth of the lake.

  17. Entrevista al profesor D. Michael Walker. - Interview with Professor D. Michael Walker.

    Directory of Open Access Journals (Sweden)

    Caravaca Guerrero, Consuelo Isabel

    2014-12-01

    Full Text Available Entrevistar a un investigador de la talla de D. Michael Walker supone hablar de un investigador reconocido a nivel nacional e internacional, uno de los mayores expertos en evolución humana de nuestros días. Nació en Colchester (Inglaterra en 1941 y tiene doble nacionalidad: británica y australiana. Actualmente es profesor emérito de la Universidad de Murcia en el Departamento de Zoología y Antropología Física de la Facultad de Biología. Pero su currículum no acaba aquí, Michael realizó tres carreras, Fisiología Animal, Medicina, y Arqueología Prehistórica, en la Universidad de Oxford. Es Doctor por esta universidad, gracias a su tesis leída sobre Paleoantropología y Prehistoria de las cuencas de los ríos Segura y Vinalopó. Nuestro entrevistado, también fue elegido Académico (Fellow –F.S.A.- en 1988 de la Society of Antiquaries of Londono SAL. Fundada en 1707, la SAL es la equivalente británica de la española Real Academia de la Historia. Es Fellow también del Real Instituto Antropológico de la Gran Bretaña (Royal Anthropological Institute of Great Britain y socio emérito de la Asociación Americana de Antropólogos Físicos (American Association of Physical Anthropologists.

  18. Reduced incidence of cardiac arrhythmias in walkers and runners.

    Directory of Open Access Journals (Sweden)

    Paul T Williams

    Full Text Available PURPOSE: Walking is purported to reduce the risk of atrial fibrillation by 48%, whereas jogging is purported to increase its risk by 53%, suggesting a strong anti-arrhythmic benefit of walking over running. The purpose of these analyses is to compare incident self-reported physician-diagnosed cardiac arrhythmia to baseline energy expenditure (metabolic equivalent hours per day, METhr/d from walking, running and other exercise. METHODS: Proportional hazards analysis of 14,734 walkers and 32,073 runners. RESULTS: There were 1,060 incident cardiac arrhythmias (412 walkers, 648 runners during 6.2 years of follow-up. The risk for incident cardiac arrhythmias declined 4.4% per baseline METhr/d walked by the walkers, or running in the runners (P = 0.0001. Specifically, the risk declined 14.2% (hazard ratio: 0.858 for 1.8 to 3.6 METhr/d, 26.5% for 3.6 to 5.4 METhr/d, and 31.7% for ≥5.4 METhr/d, relative to <1.8 METhr/d. The risk reduction per METhr/d was significantly greater for walking than running (P<0.01, but only because walkers were at 34% greater risk than runners who fell below contemporary physical activity guideline recommendations; otherwise the walkers and runners had similar risks for cardiac arrhythmias. Cardiac arrhythmias were unrelated to walking and running intensity, and unrelated to marathon participation and performance. CONCLUSIONS: The risk for cardiac arrhythmias was similar in walkers and runners who expended comparable METhr/d during structured exercise. We found no significant risk increase for self-reported cardiac arrhythmias associated with running distance, exercise intensity, or marathon participation. Rhythm abnormalities were based on self-report, precluding definitive categorization of the nature of the rhythm disturbance. However, even if the runners' arrhythmias include sinus bradycardia due to running itself, there was no increase in arrhythmias with greater running distance.

  19. Revalidation of Ceresa terminalis walker and its placement in Stictocephala Stål (Hemiptera, Membracidae Revalidação de Ceresa terminalis walker e sua alocação em Stictocephala Stål (Hemiptera, Membracidae

    Directory of Open Access Journals (Sweden)

    Gabriel S. de Andrade

    2005-12-01

    Full Text Available Ceresa terminalis Walker, 1851 is reinstated and transferred to Stictocephala Stål, 1869: Stictocephala terminalis (Walker, 1851 sp. rev., comb. nov.Ceresa terminalis Walker, 1851 é revalidada e transferida para Stictocephala Stål, 1869: Stictocephala terminalis (Walker, 1851 sp. rev., comb. nov.

  20. Realities of the Watershed Management Approach: The Magat Watershed Experience

    OpenAIRE

    Elazegui, Dulce D.; Combalicer, Edwin A.

    2004-01-01

    This paper aims to showcase the experience of the Magat watershed in the implementation of the watershed management approach. Magat watershed was declared as a forest-reservation area through Proclamation No. 573 on June 26, 1969 because of its great importance to human survival and environmental balance in the region. The Magat case demonstrates the important role that ‘champions’ like the local government unit (LGU) could play in managing the country’s watersheds. With the Nueva Viscaya pro...

  1. Reaction rate in an evanescent random walkers system

    CERN Document Server

    Ré, Miguel A

    2015-01-01

    Diffusion mediated reaction models are particularly ubiquitous in the description of physical, chemical or biological processes. The random walk schema is a useful tool for formulating these models. Recently, evanescent random walk models have received attention in order to include finite lifetime processes. For instance, activated chemical reactions, such as laser photolysis, exhibit a different asymptotic limit when compared with immortal walker models. A diffusion limited reaction model based on a one dimensional continuous time random walk on a lattice with evanescent walkers is presented here. The absorption probability density and the reaction rate are analytically calculated in the Laplace domain. A finite absorption rate is considered, a model usually referred to as imperfect trapping. Short and long time behaviors are analyzed.

  2. Friedman-Robertson-Walker Models with Late-Time Acceleration

    Institute of Scientific and Technical Information of China (English)

    Abdussattar; S. R. Prajapati2

    2011-01-01

    @@ In order to account for the observed cosmic acceleration, a modiGcation of the ansatz for the variation of density in Friedman-Robertson-Walker (FRW) FRW models given by Islam is proposed.The modified ansatz leads to an equation of state which corresponds to that of a variable Chaplygin gas, which in the course of evolution reduces to that of a modified generalized Chaplygin gas (MGCG) and a Chaplygin gas (CG), exhibiting late-time acceleration.%In order to account for the observed cosmic acceleration, a modification of the ansatz for the variation of density in Friedman-Robertson-Walker (FRW) FRW models given by Islam is proposed. The modified ansatz leads to an equation of state which corresponds to that of a variable Chaplygin gas, which in the course of evolution reduces to that ora modified generalized Chaplygin gas (MGCG) and a Chaplygin gas (CG), exhibiting late-time acceleration.

  3. Record of Diglyphus walker (Hymenoptera: Eulophidae) species in Brazil.

    Science.gov (United States)

    Carvalho, A R; Bueno, V H P; Silva, D B; Costa, V A

    2011-01-01

    Leafminers (Diptera: Agromyzidae) are pests of various crops, mainly in greenhouses, and have Diglyphus spp. as important leafminer larval parasitoids. Until recently, only Diglyphus insularis (Gahan) had been reported in Brazil. In here we report the first records of Diglyphus begini (Ashmead), D. intermedius (Girault) and D. isaea (Walker) in Brazil. These parasitoids were found parasitizing leafminer larvae on cultivated and spontaneous plants in some areas of Minas Gerais state, Brazil.

  4. Friedman—Robertson—Walker Models with Late-Time Acceleration

    Science.gov (United States)

    Abdussattar; Prajapati, S. R.

    2011-02-01

    In order to account for the observed cosmic acceleration, a modification of the ansatz for the variation of density in Friedman—Robertson—Walker (FRW) FRW models given by Islam is proposed. The modified ansatz leads to an equation of state which corresponds to that of a variable Chaplygin gas, which in the course of evolution reduces to that of a modified generalized Chaplygin gas (MGCG) and a Chaplygin gas (CG), exhibiting late-time acceleration.

  5. Friedmann-Robertson-Walker Models with Late-Time Acceleration

    CERN Document Server

    Abdussattar,

    2016-01-01

    In order to account for the observed cosmic acceleration, a modification of the ansatz for the variation of density in Friedman-Robertson-Walker (FRW) models given by Islam is proposed. The modified ansatz leads to an equation of state which corresponds to that of a variable Chaplygin gas, which in the course of evolution reduces to that of a modified generalized Chaplygin gas (MGCG) and a Chaplygin gas (CG), exhibiting late-time acceleration.

  6. On the existence of perturbed Robertson-Walker universes

    Energy Technology Data Exchange (ETDEWEB)

    D' Eath, P.D.

    1976-05-01

    Solutions of the full nonlinear field equations of general relativity near the Robertson-Walker universes are examined, together with their relation to linearized perturbations. A method due to Choquet-Bruhat and Deser is used to prove existence theorems for solutions near Robertson-Walker constraint data of the constraint equations on a spacelike hypersurface. These theorems allow one to regard the matter fluctuations as independent quantities, ranging over certain function spaces. In the k=-1 case the existence theory describes perturbations which may vary within uniform bounds throughout space. When k=+1 a modification of the method leads to a theorem which clarifies some unusual features of these constraint perturbations. The k=0 existence theorem refers only to perturbations which die away at large distances. The connection between linearized constraint solutions and solutions of the full constraints is discussed. For k= +- 1 backgrounds, solutions of the linearized constraints are analyzed using transverse-traceless decompositions of symmetric tensors. Finally the time-evolution of perturbed constraint data and the validity of linearized perturbation theory for Robertson-Walker universes are considered. (AIP)

  7. Melons are branched polymers

    CERN Document Server

    Gurau, Razvan

    2013-01-01

    Melonic graphs constitute the family of graphs arising at leading order in the 1/N expansion of tensor models. They were shown to lead to a continuum phase, reminiscent of branched polymers. We show here that they are in fact precisely branched polymers, that is, they possess Hausdorff dimension 2 and spectral dimension 4/3.

  8. Coherent branching feature bisimulation

    Directory of Open Access Journals (Sweden)

    Tessa Belder

    2015-04-01

    Full Text Available Progress in the behavioral analysis of software product lines at the family level benefits from further development of the underlying semantical theory. Here, we propose a behavioral equivalence for feature transition systems (FTS generalizing branching bisimulation for labeled transition systems (LTS. We prove that branching feature bisimulation for an FTS of a family of products coincides with branching bisimulation for the LTS projection of each the individual products. For a restricted notion of coherent branching feature bisimulation we furthermore present a minimization algorithm and show its correctness. Although the minimization problem for coherent branching feature bisimulation is shown to be intractable, application of the algorithm in the setting of a small case study results in a significant speed-up of model checking of behavioral properties.

  9. Designing for Watershed Inquiry

    Science.gov (United States)

    Bodzin, Alec; Shive, Louise

    2004-01-01

    In this article, we describe a collaborative design initiative with three secondary school teachers to promote the use of Web-based inquiry in the context of a watershed investigation. Design interviews that focus on instructional goals and pedagogical beliefs of classroom teachers were conducted. The interview protocol used a curricular framework…

  10. Watersheds in disordered media

    Directory of Open Access Journals (Sweden)

    José S. Andrade Jr.

    2015-02-01

    Full Text Available What is the best way to divide a rugged landscape? Since ancient times, watershedsseparating adjacent water systems that flow, for example, toward different seas, have beenused to delimit boundaries. Interestingly, serious and even tense border disputes betweencountries have relied on the subtle geometrical properties of these tortuous lines. For instance,slight and even anthropogenic modifications of landscapes can produce large changes in awatershed, and the effects can be highly nonlocal. Although the watershed concept arisesnaturally in geomorphology, where it plays a fundamental role in water management, landslide,and flood prevention, it also has important applications in seemingly unrelated fields suchas image processing and medicine. Despite the far-reaching consequences of the scalingproperties on watershed-related hydrological and political issues, it was only recently that a moreprofound and revealing connection has been disclosed between the concept of watershed andstatistical physics of disordered systems. This review initially surveys the origin and definition of awatershed line in a geomorphological framework to subsequently introduce its basic geometricaland physical properties. Results on statistical properties of watersheds obtained from artificialmodel landscapes generated with long-range correlations are presented and shown to be ingood qualitative and quantitative agreement with real landscapes.

  11. Watershed hydrology. Chapter 7.

    Science.gov (United States)

    Elons S. Verry; Kenneth N. Brooks; Dale S. Nichols; Dawn R. Ferris; Stephen D. Sebestyen

    2011-01-01

    Watershed hydrology is determined by the local climate, land use, and pathways of water flow. At the Marcell Experimental Forest (MEF), streamflow is dominated by spring runoff events driven by snowmelt and spring rains common to the strongly continental climate of northern Minnesota. Snowmelt and rainfall in early spring saturate both mineral and organic soils and...

  12. Fundamentals of watershed hydrology

    Science.gov (United States)

    Pamela J. Edwards; Karl W.J. Williard; Jon E. Schoonover

    2015-01-01

    This is a primer about hydrology, the science of water. Watersheds are the basic land unit for water resource management and their delineation, importance, and variation are explained and illustrated. The hydrologic cycle and its components (precipitation, evaporation, transpiration, soil water, groundwater, and streamflow) which collectively provide a foundation for...

  13. Allegheny County Watershed Boundaries

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the 52 isolated sub-Watersheds of Allegheny County that drain to single point on the main stem rivers. Created by 3 Rivers 2nd Nature based...

  14. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  15. Coherent branching feature bisimulation

    NARCIS (Netherlands)

    T. Belder (Tessa); M.H. ter Beek (Maurice); E.P. de Vink (Erik Peter)

    2015-01-01

    textabstractProgress in the behavioral analysis of software product lines at the family level benefits from further development of the underlying semantical theory. Here, we propose a behavioral equivalence for feature transition systems (FTS) generalizing branching bisimulation for labeled

  16. Koenigs function and branching processes

    CERN Document Server

    Chikilev, O G

    2001-01-01

    An explicit solution of time-homogeneous pure birth branching processes is described. It gives alternative extensions for the negative binomial distribution (branching processes with immigration) and for the Furry-Yule distribution (branching processes without immigration).

  17. Branched Polymer Revisited

    CERN Document Server

    Aoki, H; Kawai, H; Kitazawa, Y; Aoki, Hajime; Iso, Satoshi; Kawai, Hikaru; Kitazawa, Yoshihisa

    2000-01-01

    We show that correlation functions for branched polymers correspond to those for $\\phi^3$ theory with a single mass insertion, not those for the $\\phi^3$ theory themselves, as has been widely believed. In particular, the two-point function behaves as 1/p^4, not as 1/p^2. This behavior is consistent with the fact that the Hausdorff dimension of the branched polymer is four.

  18. Mechanical-Kinetic Modeling of a Molecular Walker from a Modular Design Principle

    Science.gov (United States)

    Hou, Ruizheng; Loh, Iong Ying; Li, Hongrong; Wang, Zhisong

    2017-02-01

    Artificial molecular walkers beyond burnt-bridge designs are complex nanomachines that potentially replicate biological walkers in mechanisms and functionalities. Improving the man-made walkers up to performance for widespread applications remains difficult, largely because their biomimetic design principles involve entangled kinetic and mechanical effects to complicate the link between a walker's construction and ultimate performance. Here, a synergic mechanical-kinetic model is developed for a recently reported DNA bipedal walker, which is based on a modular design principle, potentially enabling many directional walkers driven by a length-switching engine. The model reproduces the experimental data of the walker, and identifies its performance-limiting factors. The model also captures features common to the underlying design principle, including counterintuitive performance-construction relations that are explained by detailed balance, entropy production, and bias cancellation. While indicating a low directional fidelity for the present walker, the model suggests the possibility of improving the fidelity above 90% by a more powerful engine, which may be an improved version of the present engine or an entirely new engine motif, thanks to the flexible design principle. The model is readily adaptable to aid these experimental developments towards high-performance molecular walkers.

  19. Beyond the Friedmann-Lemaatre-Robertson-Walker Big Bang Singularity

    Institute of Scientific and Technical Information of China (English)

    Cristi Stoica

    2012-01-01

    Einstein's equation,in its standard form,breaks down at the Big Bang singularity.A new version,equivalent to Einstein's whenever the latter is defined,but applicable in wider situations,is proposed.The new equation remains smooth at the Big Bang singularity of the Friedmann-Lemaatre-Robertson-Walker model.It is a tensor equation defined in terms of the Ricci part of the Riemann curvature.It is obtained by taking the Kulkarni-Nomizu product between Einstein's equation and the metric tensor.

  20. The insecticide resistance in stripped stem borer, Chilo suppressalis (Walker)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ The stripped stem borer (SSB), Chilo suppressalis (Walker) is one of the major insect pests of rice in China. Chemical control has been a common practice in SSB management since 1950s. Insecticides used included BHC before 1983;organophosphorus insecticides (methyl-parathion, trichophon, methamidophos, and monocrotophos), and chlordimeform in mid-1970s-1980s; Shachongshuang (dimehypo) and Shachongdan (monousltap) since early 1980s. In recent years, SSB population and its damage to rice increased rapidly and failures on control has been reported. To find out the cause of failure and to put forward the suitable control methods, we studied the resistance of SSB to major insecticides used in China.

  1. Number of distinct sites visited by a subdiffusive random walker.

    Science.gov (United States)

    Yuste, Santos Bravo; Klafter, J; Lindenberg, Katja

    2008-03-01

    The asymptotic mean number of distinct sites visited by a subdiffusive continuous-time random walker in two dimensions seems not to have been explicitly calculated anywhere in the literature. This number has been calculated for other dimensions for only one specific asymptotic behavior of the waiting time distribution between steps. We present an explicit derivation for two cases in all integer dimensions so as to formally complete a tableau of results. In this tableau we include the dominant as well as subdominant contributions in all integer dimensions. Other quantities that can be calculated from the mean number of distinct sites visited are also discussed.

  2. On signature transition in Robertson-Walker cosmologies

    CERN Document Server

    Ghafoori-Tabrizi, K; Sepangi, H R

    2000-01-01

    We analyse a classical model of gravitation coupled to a self interacting scalar field. We show that, within the context of this model for Robertson-Walker cosmologies, there exist solutions in the spatially non-flat cases exhibiting transitions from a Euclidean to a Lorentzian spacetime. We then discuss the conditions under which these signature changing solutions to Einstein's field equations exist. In particular, we find that an upper bound for the cosmological constant exists and that close to the signature changing hypersurface, both the scale factor and the scalar field have to be constant. Moreover we find that the signature changing solutions do not exist when the scalar field is massless.

  3. Difficulties with Prenatal Diagnosis of the Walker-Warburg Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Low, A.S.C.; Lee, S.L.; Tan, A.S.A.; Chan, D.K.L.; Chan, L.L. [Singapore General Hospital (Singapore). Depts. of Diagnostic Radiology, Obstetrics and Gynecology and Neonatology

    2005-10-01

    We describe a postnatally diagnosed case of Walker-Warburg syndrome - a form of congenital muscular dystrophy with lissencephaly and eye abnormalities. We reviewed the literature to highlight its clinico-radiological diagnostic features and discuss the difficulties encountered with prenatal diagnosis, especially in cases with no positive family history. An increased awareness of this rare but lethal condition, and a high index of suspicion during routine antenatal ultrasound, could prompt further advanced fetal ultrasonography and magnetic resonance imaging, and aid in timely prenatal diagnosis, management, and counseling. Brain/brainstem, congenital, magnetic resonance imaging, obstetrics, pediatrics, ultrasound.

  4. Le fonds Alexander Walker de la Cineteca di Friouli

    OpenAIRE

    Codelli, Lorenzo

    2012-01-01

    La Collection Alexander Walker conservée à la Bibliothèque Angelo R. Humouda de la Cineteca del Friuli, à Gemona, Italie, inclût le patrimoine libraire entier, ainsi que la correspondence et tous les manuscripts d’un des critiques et essayistes anglosaxons les plus connus et influents de sa génération. Ses polémiques contre la censure, sa collaboration avec Stanley Kubrick pour la toute première monographie parue sur l’auteur de 2001 : L’Odyssée de l’espace, ses recherches fouillées sur Josep...

  5. Gravitational birefringence of light in Robertson-Walker cosmologies

    CERN Document Server

    Duval, C

    2016-01-01

    The spacetime evolution of massless spinning particles in a Robertson-Walker background is derived using the deterministic system of equations of motion due to Papapetrou, Souriau and Saturnini. A numerical integration of this system of differential equations in the case of the standard model is performed. The deviation of the photon worldlines from the null geodesics is of the order of the wavelength. Perturbative solutions are also worked out in a more general case. An experimental measurement of this deviation would test the acceleration of our expanding universe.

  6. Interpretation of simple and cloud-resolving simulations of moist convection radiation interaction with a mock-Walker circulation

    Science.gov (United States)

    Bretherton, Christopher S.; Blossey, Peter N.; Peters, Matthew E.

    2006-11-01

    An idealized two-dimensional mock-Walker circulation in the tropical atmosphere forced by prescribed horizontal gradients in sea-surface temperature (SST) is discussed. This model problem includes feedbacks between cumulus convection and tropical large-scale circulations that have proved challenging for global climate models to predict accurately. Three-dimensional cloud-resolving model (CRM) simulations that explicitly simulate turbulent circulations within individual cloud systems across 4,096 and 1,024 km-wide Walker circulations are compared with a simple theoretical model, the Simplified Quasiequilibrium Tropical Circulation Model (SQTCM). This theoretical model combines the weak-temperature-gradient approximation with a unimodal truncation of tropospheric vertical structure coupled to highly simplified formulations of moist precipitating cumulus convection and its cloud-radiative feedbacks. The rainfall, cloud and humidity distribution, circulation strength, energy fluxes and scaling properties are compared between the models. The CRM-simulated horizontal distribution of rainfall and energy fluxes are adequately predicted by the SQTCM. However, the humidity distribution (drier subsidence regions and high-humidity boundary layers in the CRM), vertical structure and domain-size scaling of the circulation differ significantly between the models. For the SQTCM, the concept of gross moist stability related to advection of moist static energy (MSE) out of tropospheric columns by the mean divergent circulation is used to explain the width and intensity of the rainy region. Column MSE budgets averaged across the ascent branch of the simulated Walker circulation provide similar insight into the cloud-resolving simulations after consideration of the more complex horizontal and vertical circulation structure and the role of transient eddies. A nondimensional ascent-region moist stability ratio α, analogous to the SQTCM gross moist stability, is developed. One term of

  7. Modelo experimental do carcinossarcoma 256 de Walker em bexiga de ratos Experimental model of Walker 256 carcinosarcoma in rats bladder

    Directory of Open Access Journals (Sweden)

    Conceição Aparecida Dornelas

    2006-02-01

    Full Text Available OBJETIVO: Estudar um modelo animal para tumor de bexiga com Walker 256. MÉTODOS: Bexigas de ratos Wistar foram cateterizadas via uretral e lesão de parede vesical foi realizada por compressão extrínsica, com pequena pinça, após laparotomia. A seguir 0,3 ml de suspensão contendo 3 x 10(5 células viáveis de carcinossarcoma de Walker foram instiladas em cada bexiga. Os animais foram sacrificados após oito e 13 dias. RESULTADOS: O índice de pega do tumor foi de 100%. A média de sobrevida foi de 14,5 dias. CONCLUSÃO: O modelo estudado foi eficiente e poderá levar subsídios para o estudo experimental em tratamentos de carcinomas de bexiga localmente invasivos em ratos.PURPOSE: An animal model to study bladder tumor with Walker 256. METHODS: Bladders rats Wistar was catheterized via urethra and compression lesion of the wall bladder was realized with a little clamping after laparotomy. One total of the 0,3 ml suspension with 3 x 10(5 cels viable of the carcinossarcoma was instilled into each bladder. The animals were sacrificed after eight and 13 days. RESULTS: The index of tumor incidence was 100% and the average of surviving was 14,5 days. CONCLUSION: The model estudied was efficient and will can to take subsidy the study experiemental in treatment of local invasise bladder cancer.

  8. Watershed based intelligent scissors.

    Science.gov (United States)

    Wieclawek, W; Pietka, E

    2015-07-01

    Watershed based modification of intelligent scissors has been developed. This approach requires a preprocessing phase with anisotropic diffusion to reduce subtle edges. Then, the watershed transform enhances the corridors. Finally, a roaming procedure, developed in this study, delineates the edge selected by a user. Due to a very restrictive set of pixels, subjected to the analysis, this approach significantly reduces the computational complexity. Moreover, the accuracy of the algorithm performance makes often one click point to be sufficient for one edge delineation. The method has been evaluated on structures as different in shape and appearance as the retina layers in OCT exams, chest and abdomen in CT and knee in MR studies. The accuracy is comparable with the traditional Life-Wire approach, whereas the analysis time decreases due to the reduction of the user interaction and number of pixels processed by the method.

  9. Ghana Watershed Prototype Products

    Science.gov (United States)

    ,

    2007-01-01

    Introduction/Background A number of satellite data sets are available through the U.S. Geological Survey (USGS) for monitoring land surface features. Representative data sets include Landsat, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), and Shuttle Radar Topography Mission (SRTM). The Ghana Watershed Prototype Products cover an area within southern Ghana, Africa, and include examples of the aforementioned data sets along with sample SRTM derivative data sets.

  10. De Narciso López a William Walker. El contingente anexionista cubano dentro de las huestes filibusteras de Walker

    OpenAIRE

    Suárez-Serrano, Josefina M.

    2016-01-01

    Examino la continuidad  entre  las actividades del caudillo del anexionismo cubano, Narciso López, y las del capitán de filibusteros norteamericano William Walker, en cuanto exponentes de los intereses del  recalcitrante esclavismo  del Sur y otras regiones de los Estados Unidos: de su programa y de sus tácticas, que apuntaban  a  la expansión ilimitada  de la esclavitud a expensas de México, Centroamérica y las Antillas.

  11. FreeWalker: a smart insole for longitudinal gait analysis.

    Science.gov (United States)

    Wang, Baitong; Rajput, Kuldeep Singh; Tam, Wing-Kin; Tung, Anthony K H; Yang, Zhi

    2015-08-01

    Gait analysis is an important diagnostic measure to investigate the pattern of walking. Traditional gait analysis is generally carried out in a gait lab, with equipped force and body tracking sensors, which needs a trained medical professional to interpret the results. This procedure is tedious, expensive, and unreliable and makes it difficult to track the progress across multiple visits. In this paper, we present a smart insole called FreeWalker, which provides quantitative gait analysis outside the confinement of traditional lab, at low- cost. The insole consists of eight pressure sensors and two motion tracking sensors, i.e. 3-axis accelerometer and 3-axis gyroscope. This enables measurement of under-foot pressure distribution and motion sequences in real-time. The insole is enabled with onboard SD card as well as wireless data transmission, which help in continuous gait-cycle analysis. The data is then sent to a gateway, for analysis and interpretation of data, using a user interface where gait features are graphically displayed. We also present validation result of a subject's left foot, who was asked to perform a specific task. Experiment results show that we could achieve a data-sampling rate of over 1 KHz, transmitting data up to a distance of 20 meter and maintain a battery life of around 24 hours. Taking advantage of these features, FreeWalker can be used in various applications, like medical diagnosis, rehabilitation, sports and entertainment.

  12. SYMMETRY AS CONCEPTUAL METAPHOR IN WALKER'S THE COLOR PURPLE

    Directory of Open Access Journals (Sweden)

    Elena Tapia

    2003-05-01

    Full Text Available The author analyzes three types of the conceptual metaphor of embodied symmetry in Alice Walker's novel, The color purple (1982. These metaphorical projections, perceived as equilibrium and its breakage in abstract phenomena, enable readers to reexamine issues of race, non-traditional families, and gender roles. The dis/equilibrium emerges in the novel's epistolary structure. Biological equilibrium breaks in incidents of rape and incest. Walker creates characters in the novel through default-concept opposites of black/white, submissive/dominant, male/female and others. These contraries foreground issues of race and gender. The novel's asymmetries engage readers, leading them to rethink individual character histories and motives. The removal of objects (e.g., rape, mothers deprived of children suggests conceptual asymmetry and alerts readers to parallel themes of sexual and racial oppression. Subjugation sometimes subtle, sometimes blatant- manifests in simple oppositions. In epistemological terms, readers seek causal explanations for the asymmetries of the narrative, interpreting each to recover its history.

  13. [Aicardi syndrome with Dandy-Walker type malformation].

    Science.gov (United States)

    Laguado-Herrera, Yuly V; Manrique-Hernández, Edgar F; Peñaloza-Mantilla, Camilo A; Quintero-Gómez, David A; Contreras-García, Gustavo A; Sandoval-Martínez, Diana K

    2015-07-16

    Introduccion. El sindrome de Aicardi (OMIM 304050) fue descrito en 1965. Su triada clasica esta compuesta por espasmos infantiles, agenesia parcial o total del cuerpo calloso y alteraciones oculares, como lagunas coriorretinianas. Se postula un mecanismo de herencia ligado a X dominante. Caso clinico. Niña nacida a termino, sin antecedentes familiares patologicos ni consanguinidad parental, con diagnostico prenatal de malformacion tipo Dandy-Walker, quien presento episodios convulsivos, coloboma del nervio optico, bloque vertebral toracico con presencia de escoliosis, ecografia transfontanelar con agenesia del cuerpo calloso y cariotipo 46,XX. Se diagnostico de sindrome de Aicardi y fallecio con mes y medio de edad. En la autopsia se evidencio hidrocefalia supratentorial con presencia de papiloma de los plexos coroideos, quiste en la fosa posterior (cuarto ventriculo), hipoplasia del vermis cerebeloso, agenesia del hemisferio del cuerpo calloso y cerebeloso izquierdo, rasgos faciales caracteristicos del sindrome, paladar ojival, pectus excavatum, escoliosis, quiste paraovarico y hepatomegalia. Conclusiones. Pocos casos han descrito la asociacion de la patologia y la presencia de malformacion de Dandy-Walker. Se comunica un nuevo caso con esta asociacion, teniendo en cuenta que las alteraciones relacionadas, principalmente agenesia o hipoplasia del cuerpo calloso, sugieren que tiene un componente genetico de base. El estudio de busqueda de la etiologia de centrarse en evaluar aquellos genes que tengan relacion con el neurodesarrollo y su activacion en la etapa de organogenia. El diagnostico definitivo establece el pronostico, manejo y asesoria genetica a la familia.

  14. Optimal recruitment strategies for groups of interacting walkers with leaders

    Science.gov (United States)

    Martínez-García, Ricardo; López, Cristóbal; Vazquez, Federico

    2015-02-01

    We introduce a model of interacting random walkers on a finite one-dimensional chain with absorbing boundaries or targets at the ends. Walkers are of two types: informed particles that move ballistically towards a given target and diffusing uninformed particles that are biased towards close informed individuals. This model mimics the dynamics of hierarchical groups of animals, where an informed individual tries to persuade and lead the movement of its conspecifics. We characterize the success of this persuasion by the first-passage probability of the uninformed particle to the target, and we interpret the speed of the informed particle as a strategic parameter that the particle can tune to maximize its success. We find that the success probability is nonmonotonic, reaching its maximum at an intermediate speed whose value increases with the diffusing rate of the uninformed particle. When two different groups of informed leaders traveling in opposite directions compete, usually the largest group is the most successful. However, the minority can reverse this situation and become the most probable winner by following two different strategies: increasing its attraction strength or adjusting its speed to an optimal value relative to the majority's speed.

  15. Metalloproteins during development of Walker-256 carcinosarcoma resistant phenotype

    Directory of Open Access Journals (Sweden)

    V. F. Chekhun

    2015-04-01

    Full Text Available The study was focused on the detection of changes in serum and tumor metal-containing proteins in animals during development of doxorubicin-resistant phenotype in malignant cells after 12 courses of chemotherapy. We found that on every stage of resistance development there was a significant increase in content of ferritin and transferrin proteins (which take part in iron traffick and storage in Walker-256 carcinosarcoma tissue. We observed decreased serum ferritin levels at the beginning stage of the resistance development and significant elevation of this protein levels in the cases with fully developed resistance phenotype. Transferrin content showed changes opposite to that of ferritin. During the development of resistance phenotype the tumor tissue also exhibited increased ‘free iron’ concentration that putatively correlate with elevation of ROS generation and levels of MMP-2 and MMP-9 active forms. The tumor non-protein thiol content increases gradually as well. The serum of animals with early stages of resistance phenotype development showed high ceruloplasmin activity and its significant reduction after loss of tumor sensitivity to doxorubicin. Therefore, the development of resistance phenotype in Walker-256 carcinosarcoma is accompanied by both the deregulation of metal-containing proteins in serum and tumor tissue and by the changes in activity of antioxidant defense system. Thus, the results of this study allow us to determine the spectrum of metal-containing proteins that are involved in the development of resistant tumor phenotype and that may be targeted for methods for doxorubicin sensitivity correction therapy.

  16. Fuzzy Random Walkers with Second Order Bounds: An Asymmetric Analysis

    Directory of Open Access Journals (Sweden)

    Georgios Drakopoulos

    2017-03-01

    Full Text Available Edge-fuzzy graphs constitute an essential modeling paradigm across a broad spectrum of domains ranging from artificial intelligence to computational neuroscience and social network analysis. Under this model, fundamental graph properties such as edge length and graph diameter become stochastic and as such they are consequently expressed in probabilistic terms. Thus, algorithms for fuzzy graph analysis must rely on non-deterministic design principles. One such principle is Random Walker, which is based on a virtual entity and selects either edges or, like in this case, vertices of a fuzzy graph to visit. This allows the estimation of global graph properties through a long sequence of local decisions, making it a viable strategy candidate for graph processing software relying on native graph databases such as Neo4j. As a concrete example, Chebyshev Walktrap, a heuristic fuzzy community discovery algorithm relying on second order statistics and on the teleportation of the Random Walker, is proposed and its performance, expressed in terms of community coherence and number of vertex visits, is compared to the previously proposed algorithms of Markov Walktrap, Fuzzy Walktrap, and Fuzzy Newman–Girvan. In order to facilitate this comparison, a metric based on the asymmetric metrics of Tversky index and Kullback–Leibler divergence is used.

  17. Damage Tolerance Assessment Branch

    Science.gov (United States)

    Walker, James L.

    2013-01-01

    The Damage Tolerance Assessment Branch evaluates the ability of a structure to perform reliably throughout its service life in the presence of a defect, crack, or other form of damage. Such assessment is fundamental to the use of structural materials and requires an integral blend of materials engineering, fracture testing and analysis, and nondestructive evaluation. The vision of the Branch is to increase the safety of manned space flight by improving the fracture control and the associated nondestructive evaluation processes through development and application of standards, guidelines, advanced test and analytical methods. The Branch also strives to assist and solve non-aerospace related NDE and damage tolerance problems, providing consultation, prototyping and inspection services.

  18. Right bundle branch block

    DEFF Research Database (Denmark)

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included.......5%/2.3% in women, P Right bundle branch block was associated with significantly...... increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch block was associated...

  19. Wrist joint moments of walker-assisted gait:a study of biomechanics and instrumentation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    While walkers are commonly prescribed to improve patient stability and ambulatory ability,quantitativestudy of the biomechanical and functional requirements for effective walker use is limited.To investigate the changesin wrist joint moments that occur with the use of a standard walker,a strain gauge-based walker instrumentation system was developed for the measurement of wrist joint moments.This walker dynamometer was integrated with an upper extremity biomechanical model.Preliminary system data were collected for twelve healthy,right-handed young adultsfollowing informed consent.Bilateral upper extremity kinematic data were acquired with a six-camera motion analysis system.Internal joint moments at the wrist were determined in the three clinical planes using the inverse dynamics method.Results showed that during a walker-assisted gait there were several typical demands of wrist abductor,adductor,flexor and external rotator.An interesting " bare phase " of wrist joint moments was also found in phaseangle[-30°,30°] of gait cycle.Complete description of wrist joint moments during walker-assisted gait may provide insight into walker use parameters and rehabilitative strategies.

  20. Watershed councils: it takes a community to restore a watershed

    Science.gov (United States)

    Marie Oliver; Rebecca Flitcroft

    2011-01-01

    Regulation alone cannot solve complex ecological problems on private lands that are managed for diverse uses. Executing coordinated restoration projects at the watershed scale is only possible with the cooperation and commitment of all stakeholders. Locally organized, nonregulatory watershed councils have proven to be a powerful method of engaging citizens from all...

  1. Radioiodinated branched carbohydrates

    Science.gov (United States)

    Goodman, Mark M.; Knapp, Jr., Furn F.

    1989-01-01

    A radioiodinated branched carbohydrate for tissue imaging. Iodine-123 is stabilized in the compound by attaching it to a vinyl functional group that is on the carbohydrate. The compound exhibits good uptake and retention and is promising in the development of radiopharmaceuticals for brain, heart and tumor imaging.

  2. Multimode geodesic branching components

    Science.gov (United States)

    Schulz, D.; Voges, E.

    1983-01-01

    Geodesic branching components are investigated for multimode guided wave optics. Geodesic structures with particular properties, e.g. focussing star couplers, are derived by a synthesis technique based on a theorem of Toraldo di Francia. Experimentally, the geodesic surfaces are printed on acrylic glass and are spin-coated with organic film waveguides.

  3. Tracheobronchial Branching Anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

    2010-04-15

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  4. Improved solubility of replication factor C (RFC) Walker A mutants.

    Science.gov (United States)

    Marzahn, Melissa R; Bloom, Linda B

    2012-06-01

    Protein insolubility often poses a significant problem during purification protocols and in enzyme assays, especially for eukaryotic proteins expressed in a recombinant bacterial system. The limited solubility of replication factor C (RFC), the clamp loader complex from Saccharomyces cerevisiae, has been previously documented. We found that mutant forms of RFC harboring a single point mutation in the Walker A motif were even less soluble than the wild-type complex. The addition of maltose at 0.75 M to the storage and assay buffers greatly increases protein solubility and prevents the complex from falling apart. Our analysis of the clamp loading reaction is dependent on fluorescence-based assays, which are environmentally sensitive. Using wt RFC as a control, we show that the addition of maltose to the reaction buffers does not affect fluorophore responses in the assays or the enzyme activity, indicating that maltose can be used as a buffer additive for further downstream analysis of these mutants.

  5. Electromagnetic Radiation in Multiply Connected Robertson-Walker Cosmologies

    CERN Document Server

    Tomaschitz, R

    1993-01-01

    Maxwell's equations on a topologically nontrivial cosmological background are studied. The cosmology is locally determined by a Robertson-Walker line element, but the spacelike slices are open hyperbolic manifolds, whose topology and geometry may vary in time. In this context the spectral resolution of Maxwell's equations in terms of horospherical elementary waves generated at infinity of hyperbolic space is given. The wave fronts are orthogonal to bundles of unstable geodesic rays, and the eikonal of geometric optics appears just as the phase of the horospherical waves. This fact is used to attach to the unstable geodesic rays a quantum mechanical momentum. In doing so the quantized energy-momentum tensor of the radiation field is constructed in a geometrically and dynamically transparent way, without appealing to the intricacies of the second quantization. In particular Planck's radiation formula, and the bearing of the multiply connected topology on the fluctuations in the temperature of the background rad...

  6. Classical and Quantum Dispersion in Robertson-Walker Cosmologies

    CERN Document Server

    Tomaschitz, R

    1993-01-01

    The instability of world lines in Robertson-Walker universes of negative spatial curvature is investigated. A probabilistic description of this instability, similar to the Liouville equation, is developed, but in a manifestly covariant, non-Hamiltonian form. To achieve this the concept of a horospherical geodesic flow of expanding bundles of parallel world lines is introduced. An invariant measure and a covariant evolution equation for the probability density on which this flow acts is constructed. The orthogonal surfaces to these bundles of trajectories are horospheres, closed surfaces in three-space, touching the boundary at infinity of hyperbolic space, where the flow lines emerge. These horospheres are just the wave fronts of spherical waves, which constitute a complete set of eigenfunctions of the Klein-Gordon equation. This fact suggests that the evolution of the quantum mechanical density with the classical one be compared, and asymptotic identity in the asymptotically flat region is found. This leads,...

  7. Random Walker Ranking for NCAA Division I-A Football

    CERN Document Server

    Callaghan, T; Mucha, P J; Callaghan, Thomas; Porter, Mason A.; Mucha, Peter J.

    2003-01-01

    We develop a one-parameter family of ranking systems for NCAA Division I-A football teams based on a collection of voters, each with a single vote, executing independent random walks on a network defined by the teams (vertices) and the games played (edges). The virtue of this class of ranking systems lies in the simplicity of its explanation. We discuss the statistical properties of the randomly walking voters and relate them to the community structure of the underlying network. We compare the results of these rankings for recent seasons with Bowl Championship Series standings and component rankings. To better understand this ranking system, we also examine the asymptotic behaviors of the aggregate of walkers. Finally, we consider possible generalizations to this ranking algorithm.

  8. Walker-Warburg syndrome: report of two cases

    Directory of Open Access Journals (Sweden)

    VASCONCELOS MARCIO M.

    1999-01-01

    Full Text Available The purpose of this study is to describe two infants that were diagnosed with Walker-Warburg syndrome (WWS, a rare form of congenital muscular dystrophy (CMD.They were studied in their clinical, laboratory, and neuroradiologic features. The index case had a brain magnetic resonance imaging (MRI and the second patient had a head computerized tomography (CT. In addition, a literature review was performed to describe the main forms of CMD. The index case fulfilled all criteria for WWS. A brain MRI performed at age 4 months served to corroborate the clinical diagnosis, showing severe hydrocephalus, type II lissencephaly, cerebellar vermian aplasia, and a hypoplastic brain stem. The authors were able to establish a retrospective diagnosis of WWS in the index case's older sister, based upon her clinical picture and head CT report.

  9. Higgs effective potential in a perturbed Robertson-Walker background

    CERN Document Server

    Maroto, Antonio L

    2014-01-01

    We calculate the one-loop effective potential of a scalar field in a Robertson-Walker background with scalar metric perturbations. A complete set of orthonormal solutions of the perturbed equations is obtained by using the adiabatic approximation for comoving observers. After analyzing the problem of renormalization in inhomogeneous backgrounds, we get the explicit contribution of metric perturbations to the effective potential. We apply these results to the Standard Model Higgs effective potential and evaluate the effects of metric perturbations on the Higgs vacuum expectation value. Space-time variations are found, which are proportional to the gravitational slip parameter, with a typical amplitude of the order of $\\Delta\\phi/\\phi\\simeq 10^{-11}$ on cosmological scales. We also discuss possible astrophysical signatures in the Solar System and in the Milky Way that could open new possibilities to explore the symmetry breaking sector of the electroweak interactions.

  10. Null hypersurfaces in generalized Robertson-Walker spacetimes

    Science.gov (United States)

    Navarro, Matias; Palmas, Oscar; Solis, Didier A.

    2016-08-01

    We study the geometry of null hypersurfaces M in generalized Robertson-Walker spacetimes. First we characterize such null hypersurfaces as graphs of generalized eikonal functions over the fiber and use this characterization to show that such hypersurfaces are parallel if and only if their fibers are also parallel. We further use this technique to construct several examples of null hypersurfaces in both de Sitter and anti de Sitter spaces. Then we characterize all the totally umbilical null hypersurfaces M in a Lorentzian space form (viewed as a quadric in a semi-Euclidean ambient space) as intersections of the space form with a hyperplane. Finally we study the totally umbilical spacelike hypersurfaces of null hypersurfaces in space forms and characterize them as planar sections of M.

  11. On Friedmann-Robertson-Walker model in conformal teleparallel gravity

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.G.; Ulhoa, S.C. [International Center of Condensed Matter Physics Universidade de Brasilia, Instituto de Fisica, Brasilia, DF (Brazil); Santos, A.F. [Universidade Federal de Mato Grosso, Instituto de Fisica, Mato Grosso (Brazil); University of Victoria, Department of Physics and Astronomy, Victoria, BC (Canada)

    2016-03-15

    In this paper we use the conformal teleparallel gravity to study an isotropic and homogeneous Universe which is settled by the Friedmann-Robertson-Walker metric. The conformal symmetry demands the existence of a scalar field which works as a dark field for this model. We solve numerically the field equations then we obtain the behavior of some cosmological parameters such as the scale factor, the deceleration parameter and the energy density of the perfect fluid which is the matter field of our model. The field equations, which we called modified Friedmann equations, allow us to define a dark fluid, with dark energy density and pressure, responsible for the acceleration in the Universe, once we defined an equation of state for the dark fluid. (orig.)

  12. Field diet of the grasshopper Abracris dilecta Walker (Orthoptera, Acrididae

    Directory of Open Access Journals (Sweden)

    Carlos Frankl Sperber

    1996-01-01

    Full Text Available Abracris dilecta Walker, 1870 (Orthoptera, Acrididae, Ommatolampinae ate leafs of at least 14 plant species, in the families Asteraceae, Lamiaceae, Malvales (Sterculiaceae, Tiliaceae or Malvaceae, Poaceae, Fabaceae, Verbenaceae, Aristolochiaceae, Rubiaceae and Melastomataccae. Elephantopus mollis H.B.K. (Asteraceae and Hyptis suaveolens Poit. (Lamiaceae comprised 50% of the diet. The diet breadth of A. dilecta was compared to that of other 11 grasshopper species of the same sub-family, with rarefaction curves. The number of plant species eaten by A. dilecta was greater than that of nine other grasshopper species of the same sub-family (Rhachicreagra spp. but was lower then two others (Microptylopteryx hebardi Rehn, 1905 and Rhachicreagra astytophallus Jago & Rowell, 1981. This results are discussed in view of the broad geographical range and possession of developed wings by A. dilecta, which contrasts with most Ommatolampinae grasshoppers.

  13. SPECIFIC DEGRADATION OF WATERSHEDS

    Institute of Scientific and Technical Information of China (English)

    Boubacar KANE; Pierre Y.JULIEN

    2007-01-01

    An extensive database of reservoir sedimentation surveys throughout continental United States is compiled and analyzed to determine specific degradation SD relationships as function of mean annual rainfall R, drainage area A, and watershed slope S. The database contains 1463 field measurements and specific degradation relationships are defined as function of A, R and S. Weak trends and significant variability in the data are noticeable. Specific degradation measurements are log normally distributed with respect to R, A, and S and 95% confidence intervals are determined accordingly. The accuracy of the predictions does not significantly increase as more independent variables are added to the regression analyses.

  14. Ecological effects of contaminants in McCoy Branch, 1991--1993

    Energy Technology Data Exchange (ETDEWEB)

    Ryon, M.G. [ed.

    1996-09-01

    The 1984 Hazardous and Solid Waste Amendments to the Resource Conservation and Recovery Act (RCRA) required assessment of all current and former solid waste management units. Following guidelines under RCRA and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), a remedial investigation (RI) was required of the Y-12 Plant for their filled coal ash pond (FCAP) and associated areas on McCoy Branch. The RI process was initiated and assessments were presented. Because the disposal of coal ash in the ash pond, McCoy Branch, and Rogers Quarry was not consistent with the Tennessee Water Quality Act, several remediation steps were implemented between 1986 and 1994 for McCoy Branch to address disposal problems. The required ecological risk assessments of McCoy Branch watershed included provisions for biological monitoring of the watershed. The objectives of the biological monitoring were to (1) document changes in biological quality of McCoy Branch after completion of a pipeline bypassing upper McCoy Branch and further, after termination of all discharges to Rogers Quarry, (2) provide guidance on the need for additional remediation, and (3) evaluate the effectiveness of implemented remedial actions. The data from the biological monitoring program may also determine whether the goals of protection of human health and the environment of McCoy Branch are being accomplished.

  15. Critical branching neural networks.

    Science.gov (United States)

    Kello, Christopher T

    2013-01-01

    It is now well-established that intrinsic variations in human neural and behavioral activity tend to exhibit scaling laws in their fluctuations and distributions. The meaning of these scaling laws is an ongoing matter of debate between isolable causes versus pervasive causes. A spiking neural network model is presented that self-tunes to critical branching and, in doing so, simulates observed scaling laws as pervasive to neural and behavioral activity. These scaling laws are related to neural and cognitive functions, in that critical branching is shown to yield spiking activity with maximal memory and encoding capacities when analyzed using reservoir computing techniques. The model is also shown to account for findings of pervasive 1/f scaling in speech and cued response behaviors that are difficult to explain by isolable causes. Issues and questions raised by the model and its results are discussed from the perspectives of physics, neuroscience, computer and information sciences, and psychological and cognitive sciences.

  16. Assessment of morphotectonic properties of Mahan Tigrani watershed

    Directory of Open Access Journals (Sweden)

    Mohammad Hosain Ramesht

    2011-10-01

    Full Text Available Tectonic geomorphology can be explained as the study of landforms produced by tectonic processes, or the application of geomorphic principles to the suggestion of tectonic problems. Tigrani's watershed is located in north part of hillside. Nayband Fault sub branch pass from the east of zone and kuhbanan fault from the north of zone supplies an appropriate theme for survey tectonic activities. For access to this aim geomorphic indexes contain Stream Length Gradient, Drainage Basin Shape Ratio, Ratio of Valley-floor with to Valley Height, Topographic Symmetry, Mountain Front Sinuosity and Asymmetry Factor with use of topographic maps, DEM, Arc GIS and Global mapper softwares have gained. The results of research which calculated with Iat index show west sub basin have medium tectonic activity (Iat=2, and east sub basin have high tectonic activity(Iat=1.5. Overall the results show that assessment of tectonic activities in Tigrani watershed this basin is active because of tectonic movements.

  17. Generalized Markov branching models

    OpenAIRE

    Li, Junping

    2005-01-01

    In this thesis, we first considered a modified Markov branching process incorporating both state-independent immigration and resurrection. After establishing the criteria for regularity and uniqueness, explicit expressions for the extinction probability and mean extinction time are presented. The criteria for recurrence and ergodicity are also established. In addition, an explicit expression for the equilibrium distribution is presented.\\ud \\ud We then moved on to investigate the basic proper...

  18. Generalized Markov branching models

    OpenAIRE

    Li, Junping

    2005-01-01

    In this thesis, we first considered a modified Markov branching process incorporating both state-independent immigration and resurrection. After establishing the criteria for regularity and uniqueness, explicit expressions for the extinction probability and mean extinction time are presented. The criteria for recurrence and ergodicity are also established. In addition, an explicit expression for the equilibrium distribution is presented. We then moved on to investigate the basic proper...

  19. Tau leptonic branching ratios

    CERN Document Server

    Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Garrido, L; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    A sample of 62249 \\tau-pair events is selected from data taken with the ALEPH detector in 1991, 1992 and 1993. The measurement of the branching fractions for \\tau decays into electrons and muons is presented with emphasis on the study of systematic effects from selection, particle identification and decay classification. Combined with the most recent ALEPH determination of the \\tau lifetime, these results provide a relative measurement of the leptonic couplings in the weak charged current for transverse W bosons.

  20. Electrochemical Energy Storage Branch

    Science.gov (United States)

    1985-01-01

    The activities of the Electrochemical Energy Storage Branch are highlighted, including the Technology Base Research and the Exploratory Technology Development and Testing projects within the Electrochemical Energy Storage Program for the 1984 fiscal year. General Headquarters activities are presented first; and then, a summary of the Director Controlled Milestones, followed by other major accomplishments. A listing of the workshops and seminars held during the year is also included.

  1. Effects of aging on identifying emotions conveyed by point-light walkers.

    Science.gov (United States)

    Spencer, Justine M Y; Sekuler, Allison B; Bennett, Patrick J; Giese, Martin A; Pilz, Karin S

    2016-02-01

    The visual system is able to recognize human motion simply from point lights attached to the major joints of an actor. Moreover, it has been shown that younger adults are able to recognize emotions from such dynamic point-light displays. Previous research has suggested that the ability to perceive emotional stimuli changes with age. For example, it has been shown that older adults are impaired in recognizing emotional expressions from static faces. In addition, it has been shown that older adults have difficulties perceiving visual motion, which might be helpful to recognize emotions from point-light displays. In the current study, 4 experiments were completed in which older and younger adults were asked to identify 3 emotions (happy, sad, and angry) displayed by 4 types of point-light walkers: upright and inverted normal walkers, which contained both local motion and global form information; upright scrambled walkers, which contained only local motion information; and upright random-position walkers, which contained only global form information. Overall, emotion discrimination accuracy was lower in older participants compared with younger participants, specifically when identifying sad and angry point-light walkers. In addition, observers in both age groups were able to recognize emotions from all types of point-light walkers, suggesting that both older and younger adults are able to recognize emotions from point-light walkers on the basis of local motion or global form.

  2. Paciente com variante da síndrome de Dandy Walker

    OpenAIRE

    Robson Luis Ribeiro Andrade Filho; Thamiris Messias Lera; Giovanna Napolitano Pereira; Izilda das Eiras Tâmega; Jacqueline Alves Rena; Bárbara Saragiotto; Rachel Serraneto Amadeu; Karine Lacerda Guimarães

    2015-01-01

    O quadro que seria conhecido atualmente como Síndrome de Dandy Walker, foi caracterizada por um conjunto de sinais derivados de alterações na embriogênese, principalmente no que tange a gênese do sistema nervoso central. A patogenia é classificada majoritariamente em três formas, sendo a mais comum a variante de Dandy Walker. Tem-se por objetivo, o relato do caso de um paciente masculino, 3 meses de idade, portador da Variante da Síndrome de Dandy Walker. O paciente apresentava ao exame físic...

  3. A variable depth search branching

    OpenAIRE

    Cornillier, Fabien; Pécora, José Eduardo; Charles, Vincent

    2017-01-01

    We introduce a variable depth search branching, an extension to the local branching for solving Mixed-Integer Programs. Two strategies are assessed, a best improvement strategy and a first improvement strategy. The extensive computational assessment evidences a significant improvement over the local branching for both strategies. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down.

  4. Watershed Boundaries - MO 2015 Metro No Discharge Watersheds (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This feature class contains watersheds associated with Missouri's use designations for streams listed in Table F - Metropolitan No-Discharge Streams of the Water...

  5. Evaluating Hydrologic Response of an Agricultural Watershed for Watershed Analysis

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Jha

    2011-06-01

    Full Text Available This paper describes the hydrological assessment of an agricultural watershed in the Midwestern United States through the use of a watershed scale hydrologic model. The Soil and Water Assessment Tool (SWAT model was applied to the Maquoketa River watershed, located in northeast Iowa, draining an agriculture intensive area of about 5,000 km2. The inputs to the model were obtained from the Environmental Protection Agency’s geographic information/database system called Better Assessment Science Integrating Point and Nonpoint Sources (BASINS. Meteorological input, including precipitation and temperature from six weather stations located in and around the watershed, and measured streamflow data at the watershed outlet, were used in the simulation. A sensitivity analysis was performed using an influence coefficient method to evaluate surface runoff and baseflow variations in response to changes in model input hydrologic parameters. The curve number, evaporation compensation factor, and soil available water capacity were found to be the most sensitive parameters among eight selected parameters. Model calibration, facilitated by the sensitivity analysis, was performed for the period 1988 through 1993, and validation was performed for 1982 through 1987. The model was found to explain at least 86% and 69% of the variability in the measured streamflow data for calibration and validation periods, respectively. This initial hydrologic assessment will facilitate future modeling applications using SWAT to the Maquoketa River watershed for various watershed analyses, including watershed assessment for water quality management, such as total maximum daily loads, impacts of land use and climate change, and impacts of alternate management practices.

  6. Combustion Branch Website Development

    Science.gov (United States)

    Bishop, Eric

    2004-01-01

    The NASA combustion branch is a leader in developing and applying combustion science to focused aerospace propulsion systems concepts. It is widely recognized for unique facilities, analytical tools, and personnel. In order to better communicate the outstanding research being done in this Branch to the public and other research organization, a more substantial website was desired. The objective of this project was to build an up-to-date site that reflects current research in a usable and attractive manner. In order to accomplish this, information was requested from all researchers in the Combustion branch, on their professional skills and on the current projects. This information was used to fill in the Personnel and Research sections of the website. A digital camera was used to photograph all personnel and these photographs were included in the personnel section as well. The design of the site was implemented using the latest web standards: xhtml and external css stylesheets. This implementation conforms to the guidelines recommended by the w3c. It also helps to ensure that the web site is accessible by disabled users, and complies with Section 508 Federal legislation (which mandates that all Federal websites be accessible). Graphics for the new site were generated using the gimp (www.gimp.org) an open-source graphics program similar to Adobe Photoshop. Also, all graphics on the site were of a reasonable size (less than 20k, most less than 2k) so that the page would load quickly. Technologies such as Macromedia Flash and Javascript were avoided, as these only function on some clients which have the proper software installed or enabled. The website was tested on different platforms with many different browsers to ensure there were no compatibility issues. The website was tested on windows with MS IE 6, MSIE 5 , Netscape 7, Mozilla and Opera. On a Mac, the site was tested with MS IE 5 , Netscape 7 and Safari.

  7. Branch formation during organ development

    Science.gov (United States)

    Gjorevski, Nikolce; Nelson, Celeste M.

    2010-01-01

    Invertebrates and vertebrates use branching morphogenesis to build epithelial trees to maximize the surface area of organs within a given volume. Several molecular regulators of branching have recently been discovered, a number of which are conserved across different organs and species. Signals that control branching at the cellular and tissue levels are also starting to emerge, and are rapidly unveiling the physical nature of branch development. Here we discuss the molecular, cellular and physical processes that govern branch formation and highlight the major outstanding questions in the field. PMID:20890968

  8. Cookie branching random walks

    CERN Document Server

    Bartsch, Christian; Kochler, Thomas; Müller, Sebastian; Popov, Serguei

    2011-01-01

    We consider a branching random walk on $\\Z$, where the particles behave differently in visited and unvisited sites. Informally, each site on the positive half-line contains initially a cookie. On the first visit of a site its cookie is removed and particles at positions with a cookie reproduce and move differently from particles on sites without cookies. Therefore, the movement and the reproduction of the particles depend on the previous behaviour of the population of particles. We study the question if the process is recurrent or transient, i.e., whether infinitely many particles visit the origin or not.

  9. The branch librarians' handbook

    CERN Document Server

    Rivers, Vickie

    2004-01-01

    ""Recommended""--Booklist; ""an excellent addition...highly recommended""--Public Libraries; ""clear...very sound advice...strongly recommend""--Catholic Library World; ""excellent resource...organized...well written""--Against the Grain; ""interesting...thoroughly practical...a very good book...well organized...clearly written""--ARBA. This handbook covers a wide variety of issues that the branch librarian must deal with every day. Chapters are devoted to mission statements (the Dallas Public Library and Dayton Metro Library mission statements are highlighted as examples), library systems,

  10. Asotin Creek Model Watershed Plan

    Energy Technology Data Exchange (ETDEWEB)

    Browne, D.; Holzmiller, J.; Koch, F.; Polumsky, S.; Schlee, D.; Thiessen, G.; Johnson, C.

    1995-04-01

    The Asotin Creek Model Watershed Plan is the first to be developed in Washington State which is specifically concerned with habitat protection and restoration for salmon and trout. The plan is consistent with the habitat element of the ``Strategy for Salmon``. Asotin Creek is similar in many ways to other salmon-bearing streams in the Snake River system. Its watershed has been significantly impacted by human activities and catastrophic natural events, such as floods and droughts. It supports only remnant salmon and trout populations compared to earlier years. It will require protection and restoration of its fish habitat and riparian corridor in order to increase its salmonid productivity. The watershed coordinator for the Asotin County Conservation District led a locally based process that combined local concerns and knowledge with technology from several agencies to produce the Asotin Creek Model Watershed Plan.

  11. Mechanism of rice variety resistance to the yellow stem borer, Scirpophaga incertulas (Walker)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Yellow stem borer (YSB), Scirpophaga incertulas (Walker) has become the main rice insect pest once again along the Changjiang River sinee 1990s. Unfortunately, no rice variety with resistance to YSB has been reported so far.

  12. POMT2 mutations cause alpha-dystroglycan hypoglycosylation and Walker-Warburg syndrome

    NARCIS (Netherlands)

    van Reeuwijk, J; Janssen, M; van den Elzen, C; de Bernabe, DBV; Sabatelli, P; Merlini, L; Boon, M; Scheffer, H; Brockington, M; Muntoni, F; Huynen, MA; Verrips, A; Walsh, CA; Barth, PG; Brunner, HG; van Bokhoven, H

    2005-01-01

    Background: Walker-Warburg syndrome (WWS) is an autosomal recessive condition characterised by congenital muscular dystrophy, structural brain defects, and eye malformations. Typical brain abnormalities are hydrocephalus, lissencephaly, agenesis of the corpus callosum, fusion of the hemispheres, cer

  13. POMT2 mutations cause alpha-dystroglycan hypoglycosylation and Walker-Warburg syndrome.

    NARCIS (Netherlands)

    Reeuwijk, J. van; Janssen, M.; Elzen, C. van der; Beltran Valero de Bernabe, D.; Sabatelli, P.; Merlini, L.; Boon, M.; Scheffer, H.; Brockington, M.; Muntoni, F.; Huynen, M.A.; Verrips, A.; Walsh, C.A.; Barth, P.G.; Brunner, H.G.; Bokhoven, J.H.L.M. van

    2005-01-01

    BACKGROUND: Walker-Warburg syndrome (WWS) is an autosomal recessive condition characterised by congenital muscular dystrophy, structural brain defects, and eye malformations. Typical brain abnormalities are hydrocephalus, lissencephaly, agenesis of the corpus callosum, fusion of the hemispheres, cer

  14. A review of Luxiaria Walker and its allied genus Calletaera Warren (Lepidoptera, Geometridae, Ennominae) from China.

    Science.gov (United States)

    Jiang, Nan; Xue, Dayong; Han, Hongxiang

    2014-08-21

    The genus Luxiaria Walker and its allied genus Calletaera Warren in China, including 16 species in all, are reviewed. Five new species are described: C. obvia sp. nov., C. acuticornuta sp. nov., C. rotundicornuta sp. nov., C. dentata sp. nov., C. trigonoprocessus sp. nov. The species L. acutaria (Snellen, 1877) and L. tephrosaria (Moore, 1868) are newly recorded for China. Two new combinations are established: C. obliquata (Moore, 1888) comb. nov. and C. consimilaria (Leech, 1897) comb. nov. Four new synonyms are established: Eutoea Walker, 1860 (= Bithiodes Warren, 1894 syn. nov.); Calletaera Warren, 1895 (=Bithiodes Warren, 1899 syn. nov.), based on the fixation of nominal type Acidalia inexactata Walker, 1861, for the genus name Bithiodes Warren, 1894; L. emphatica Prout, 1925 (= L. costinota Inoue, 1978 syn. nov.); C. subexpressa (Walker, 1861) (= C. digrammata Wehrli, 1925 syn. nov.). Diagnoses for all Chinese species are provided. Illustrations of external features and genitalia are presented. 

  15. Spacetime emergence of the robertson-walker universe from a matrix model.

    Science.gov (United States)

    Erdmenger, Johanna; Meyer, René; Park, Jeong-Hyuck

    2007-06-29

    Using a novel, string theory-inspired formalism based on a Hamiltonian constraint, we obtain a conformal mechanical system for the spatially flat four-dimensional Robertson-Walker Universe. Depending on parameter choices, this system describes either a relativistic particle in the Robertson-Walker background or metric fluctuations of the Robertson-Walker geometry. Moreover, we derive a tree-level M theory matrix model in this time-dependent background. Imposing the Hamiltonian constraint forces the spacetime geometry to be fuzzy near the big bang, while the classical Robertson-Walker geometry emerges as the Universe expands. From our approach, we also derive the temperature of the Universe interpolating between the radiation and matter dominated eras.

  16. Neurocutaneous Melanosis in Association with Dandy-Walker Complex with Extensive Intracerebral and Spinal Cord Involvement

    National Research Council Canada - National Science Library

    Sung, Kyoung-Su; Song, Young-Jin

    2014-01-01

    .... The Dandy-Walker complex (DWC) is characterized by an enlarged posterior fossa with high insertion of the tentorium, hypoplasia or aplasia of the cerebellar vermis, and cystic dilatation of the fourth ventricle...

  17. Mercury in biota and sediment in the Walker River Basin, Nevada and California

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Common loons (Gavia immer) that stage during migration at Walker Lake, Nevada, were found to have elevated concentrations of mercury in their blood. The source of...

  18. DO INFANTS USING BABY WALKERS SUFFER DEVELOPMENTAL DELAYS IN ACQUISITION OF MOTOR SKILLS?

    Directory of Open Access Journals (Sweden)

    A. Talebian

    2008-10-01

    Full Text Available  AbstractObjectiveDevelopment is a complex process, completed over a specific period of time, through the maturation of the nervous system. It is affected by genetic, ethnic, nutritional, social, and economic factors; one of the environmental factors affecting the acquisition of motor skills in infants is the use of baby walkers. Since this device is very commonly used for infants in our country, we conducted this study to evaluate its effects on the acquisition of motor skills in this age group of children.Materials & MethodsThis longitudinal study was conducted in 2005 on 300 infants referring to the Primary Health Care Centers of Kashan district in 1384; the infants were divided into two groups of 150 babies each, with the case group using baby walkers, while the other 150, the controls, did not. All babies were followed for two years, and the ages for acquisition of motor skills were documented during face-to face or telephone interviews with the parents. Data were analyzed using the T-test and the Chi Square test.ResultsOf the study population, 175 babies (58.33% were male. The mean age of acquisition of motor skills including rolling, crawling, moving on hands and feet, sitting without and with help, standing and walking dependently and independently were found to be delayed in infants using baby walkers, a difference between the two groups of walker users and non- walker users that was statistically significant (PConclusionConsidering the adverse effects that walkers have on the acquisition of motor skills in infants, as demonstrated by the results of this study, we do not recommend the use of baby walkers in infants.Keywords: Baby walker, Motor skills, Infants.   

  19. On William Walker and his Connections with and Some Secret Societies

    OpenAIRE

    Abarca Hernández, Oriester; Arias Alpízar, Luz Mary

    2016-01-01

    According to various sources, William Walker received the aid of secret societies for his filibustering raids in Central America. Four main sources were selected to examine some aspects of the problem that arises in this article: Did Walker’s projects have a real connection with secret organizations? The emphasis is on criticism of sources and any interest that lies behind the facts stated. Según diversas fuentes, William Walker recibió la ayuda de sociedades secretas para sus incursiones ...

  20. Path-valued branching processes and nonlocal branching superprocesses

    CERN Document Server

    Li, Zenghu

    2012-01-01

    A family of continuous-state branching processes with immigration are constructed as the solution flow of a stochastic equation system driven by time-space noises. The family can be regarded as an inhomogeneous increasing path-valued branching process with immigration. Two nonlocal branching immigration superprocesses can be defined from the flow. We identify explicitly the branching and immigration mechanisms of those processes. The results provide new perspectives into the tree-valued Markov processes of Aldous and Pitman [Ann. Inst. H. Poincare Probab. Statist. 34 (1998), 637--686] and Abraham and Delmas [Ann. Probab. To appear].

  1. Hydrologic Setting and Conceptual Hydrologic Model of the Walker River Basin, West-Central Nevada

    Science.gov (United States)

    Lopes, Thomas J.; Allander, Kip K.

    2009-01-01

    The Walker River is the main source of inflow to Walker Lake, a closed-basin lake in west-central Nevada. Between 1882 and 2008, agricultural diversions resulted in a lake-level decline of more than 150 feet and storage loss of 7,400,000 acre-ft. Evaporative concentration increased dissolved solids from 2,500 to 17,000 milligrams per liter. The increase in salinity threatens the survival of the Lahontan cutthroat trout, a native species listed as threatened under the Endangered Species Act. This report describes the hydrologic setting of the Walker River basin and a conceptual hydrologic model of the relations among streams, groundwater, and Walker Lake with emphasis on the lower Walker River basin from Wabuska to Hawthorne, Nevada. The Walker River basin is about 3,950 square miles and straddles the California-Nevada border. Most streamflow originates as snowmelt in the Sierra Nevada. Spring runoff from the Sierra Nevada typically reaches its peak during late May to early June with as much as 2,800 cubic feet per second in the Walker River near Wabuska. Typically, 3 to 4 consecutive years of below average streamflow are followed by 1 or 2 years of average or above average streamflow. Mountain ranges are comprised of consolidated rocks with low hydraulic conductivities, but consolidated rocks transmit water where fractured. Unconsolidated sediments include fluvial deposits along the active channel of the Walker River, valley floors, alluvial slopes, and a playa. Sand and gravel deposited by the Walker River likely are discontinuous strata throughout the valley floor. Thick clay strata likely were deposited in Pleistocene Lake Lahontan and are horizontally continuous, except where strata have been eroded by the Walker River. At Walker Lake, sediments mostly are clay interbedded with alluvial slope, fluvial, and deltaic deposits along the lake margins. Coarse sediments form a multilayered, confined-aquifer system that could extend several miles from the shoreline

  2. Quiver Varieties and Branching

    Directory of Open Access Journals (Sweden)

    Hiraku Nakajima

    2009-01-01

    Full Text Available Braverman and Finkelberg recently proposed the geometric Satake correspondence for the affine Kac-Moody group Gaff [Braverman A., Finkelberg M., arXiv:0711.2083]. They conjecture that intersection cohomology sheaves on the Uhlenbeck compactification of the framed moduli space of Gcpt-instantons on $R^4/Z_r$ correspond to weight spaces of representations of the Langlands dual group $G_{aff}^{vee}$ at level $r$. When $G = SL(l$, the Uhlenbeck compactification is the quiver variety of type $sl(r_{aff}$, and their conjecture follows from the author's earlier result and I. Frenkel's level-rank duality. They further introduce a convolution diagram which conjecturally gives the tensor product multiplicity [Braverman A., Finkelberg M., Private communication, 2008]. In this paper, we develop the theory for the branching in quiver varieties and check this conjecture for $G = SL(l$.

  3. Integrating over Higgs branches

    Energy Technology Data Exchange (ETDEWEB)

    Moore, G. [Yale Univ., New Haven, CT (United States). Dept. of Physics; Nekrasov, N. [Institute of Theoretical and Experimental Physics, 117259, Moscow (Russian Federation); Shatashvili, S. [Lyman Laboratory of Physics, Harvard University, Cambridge, MA (United States)

    2000-01-01

    We develop some useful techniques for integrating over Higgs branches in supersymmetric theories with 4 and 8 supercharges. In particular, we define a regularized volume for hyperkaehler quotients. We evaluate this volume for certain ALE and ALF spaces in terms of the hyperkaehler periods. We also reduce these volumes for a large class of hyperkaehler quotients to simpler integrals. These quotients include complex coadjoint orbits, instanton moduli spaces on R{sup 4} and ALE manifolds, Hitchin spaces, and moduli spaces of (parabolic) Higgs bundles on Riemann surfaces. In the case of Hitchin spaces the evaluation of the volume reduces to a summation over solutions of Bethe ansatz equations for the non-linear Schroedinger system. We discuss some applications of our results. (orig.)

  4. Relativistic models of thin disks immersed in a Robertson-Walker type spacetime Modelos relativistas de discos delgados inmersos en un espacio-tiempo tipo Robertson-Walker

    Directory of Open Access Journals (Sweden)

    Gonzalo García Reyes

    2013-11-01

    Full Text Available Using the well known “displace, cut and reflect” method used to generate disks from given solutions of Einstein field equations, we construct some relativistic models of time dependent thin disks of infinite extension made of a perfect fluid based on the Robertson-Walker metric. Two simple families of models of disks based on Robertson-Walker solutions admitting Matter and Ricci collineations are presented. We obtain disks that are in agreement with all the energy conditions.Usando el método de “desplazamiento, corte y reflexión” se construyen algunos modelos relativistas exactas de soluciones que representan discos delgados de extensión infinita, dependientes del tiempo y hechos de un fluido perfecto, basados en la métrica de Robertson-Walker. Se presentan dos familias simples de modelos de discos basados sobre el espacio tiempo de Robertson-Walker que admiten colineaciones de Ricci y de materia. Se obtienen modelos de discos que satisfacen todas las condiciones de energía.

  5. Obituary: Richard L. (Dick) Walker, Jr., 1938-2005

    Science.gov (United States)

    Pier, Jeffrey R.; Mason, Brian

    2005-12-01

    Dick Walker, 67, died 30 March 2005 in Flagstaff, AZ, following a long illness. He was born on 9 March 1938 in Hampton, Iowa and grew up in Waterloo, Iowa. As a child, Dick was fascinated with astronomy and built his own telescope. He saved his pennies and bought and read every book on the subject he could find. He also raised pigeons, naming four of them Hertzsprung, Hoyle, Gamow, and Kron. In 1957, the year Sputnik was launched, Dick began his college studies at the University of Northern Iowa in Cedar Falls. In 1959, he transferred to the State University of Iowa (subsequently renamed the University of Iowa) in Iowa City, where he earned a BA degree in astronomy and physics in 1963. He joined the staff of the U.S. Naval Observatory in Washington, DC, where he worked in the Time Service Division for a year before his assignment to the Astrometry and Astrophysics Division. Dick relocated to Flagstaff, AZ, in 1966 to continue his Naval Observatory service at the Flagstaff Station. His retirement in May 1999, ended a thirty-six-year career with USNO. Dick was first and foremost an observational astronomer. From the mid 1960s through the late 1970s, much of Dick's time was devoted to the measurement of binary stars, observing with the 12-inch and 26-inch refractors in Washington and later the 40-inch and 61-inch reflectors in Flagstaff. He also made many trips to Lick Observatory to work with the 36-inch Clark Refractor there. During this time he consulted with Charles Worley, who was observing on the 26-inch, to make sure time was well-spent examining doubles that could not be observed in Washington. This period of observing overlapped with the early years of speckle interferometry, and Dick's observations, made with the largest telescope used for micrometry at the time, were very important for ascertaining the veracity of this new technique. He was a studious and very careful observer of doubles and made over 8,000 measures, resulting in almost 3,000 mean positions

  6. Methods and Technologies Branch (MTB)

    Science.gov (United States)

    The Methods and Technologies Branch focuses on methods to address epidemiologic data collection, study design and analysis, and to modify technological approaches to better understand cancer susceptibility.

  7. DO INFANTS USING BABY WALKERS SUFFER DEVELOPMENTAL DELAYS IN ACQUISITION OF MOTOR SKILLS?

    Directory of Open Access Journals (Sweden)

    A. Talebian

    2008-06-01

    Full Text Available ObjectiveDevelopment is a complex process, completed over a specific period of time, through the maturation of the nervous system. It is affected by genetic, ethnic, nutritional, social, and economic factors; one of the environmental factors affecting the acquisition of motor skills in infants is the use of baby walkers. Since this device is very commonly used for infants in our country, we conducted this study to evaluate its effects on the acquisition of motor skills in this age group of children. Materials & MethodsThis longitudinal study was conducted in 2005 on 300 infants referring to the Primary Health Care Centers of Kashan district in 1384; the infants were divided into two groups of 150 babies each, with the case group using baby walkers, while the other 150, the controls, did not. All babies were followed for two years, and the ages for acquisition of motor skills were documented during face-to face or telephone interviews with the parents. Data were analyzed using the T-test and the Chi Square test.ResultsOf the study population, 175 babies (58.33% were male. The mean age of acquisition of motor skills including rolling, crawling, moving on hands and feet, sitting without and with help, standing and walking dependently and independently were found to be delayed in infants using baby walkers, a difference between the two groups of walker users and non- walker users that was statistically significant (P<0.001.ConclusionConsidering the adverse effects that walkers have on the acquisition of motor skills in infants, as demonstrated by the results of this study, we do not recommend the use of baby walkers in infants.

  8. A retrospective benefit-cost analysis of the 1997 stair-fall requirements for baby walkers.

    Science.gov (United States)

    Rodgers, Gregory B; Leland, Elizabeth W

    2008-01-01

    Based on estimates from the U.S. Consumer Product Safety Commission (CPSC), there were about 25,000 baby walker-related injuries treated annually in U.S. hospital emergency departments during the early 1990s. This amounted to about 8 injuries for every 1000 baby walkers in use. Most injuries resulted from falls down stairs. After CPSC initiated a regulatory proceeding in 1994, the CPSC staff worked with industry to address the stair-fall hazard. This cooperative effort resulted in requirements designed to prevent stair-fall injuries that became effective in 1997 as part of a revised voluntary safety standard. This study presents a retrospective benefit-cost analysis of the 1997 stair-fall requirements. The benefits were defined as the reduction in the costs of injuries resulting from the use of the safer walkers. The costs were defined as the additional resource costs associated with making baby walkers safer. The study found that the stair-fall requirements were highly effective in reducing the risk of stair-fall injury, and that the benefits of the requirements substantially exceeded the costs. The expected net benefits (i.e., benefits minus costs) amounted to an average of about $169 per walker, over the walker's expected product life. Given current U.S. sales of about 600,000 baby walkers annually, the present value of the expected net benefits associated with 1 year's production amounts to over $100 million annually. A sensitivity analysis showed that the major findings were robust with respect to variations in underlying assumptions.

  9. Watershed management and the web

    Energy Technology Data Exchange (ETDEWEB)

    Voinov, A.; Costanza, R. [Univ. of Maryland, Solomons, MD (United States). Inst. for Ecological Economics

    1999-08-01

    Watershed analysis and watershed management are developing as tools of integrated ecological and economic study. They also assist decision-making at the regional scale. The new technology and thinking offered by the advent of the Internet and the World Wide Web is highly complementary to some of the goals of watershed analysis. Services delivered by the Web are open, interactive, gas, spatially distributed, hierarchical and flexible. The Web offers the ability to display information creatively, to interact with that information and to change and modify it remotely. In this way the Internet provides a much-needed opportunity to deliver scientific findings and information to stakeholders and to link stakeholders together providing for collective decision=making. The benefits fall into two major categories: methological and educational. Methodologically the approach furthers the watershed management concept, offering an avenue for practical implementation of watershed management principles. For educational purposes the Web is a source of data and insight serving a variety of needs at all levels.

  10. Natural products-based insecticidal agents 7. Semisynthesis and insecticidal activity of novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Xiao, Xiao; Wang, Qing-tian

    2010-09-01

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 16 novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives were semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Among all the tested derivatives, especially compounds 4b, 4e, 4g, and 4p exhibited more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach. Generally, it was obviously demonstrated that the length of straight-chain or branched-chain alkyloxy, and heteroatom-containing cycloalkyloxy at the C-4 position of 2-chloropodophyllotoxin were very important for the insecticidal activity.

  11. The Watershed Algorithm for Image Segmentation

    Institute of Scientific and Technical Information of China (English)

    OU Yan; LIN Nan

    2007-01-01

    This article introduced the watershed algorithm for the segmentation, illustrated the segmation process by implementing this algorithm. By comparing with another three related algorithm, this article revealed both the advantages and drawbacks of the watershed algorithm.

  12. DNR Watersheds - DNR Level 02 - HUC 04

    Data.gov (United States)

    Minnesota Department of Natural Resources — These data consists of watershed delineations in one seamless dataset of drainage areas called Minnesota Department of Natural Resources (DNR) Level 02 Watersheds....

  13. NYC Reservoirs Watershed Areas (HUC 12)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This NYC Reservoirs Watershed Areas (HUC 12) GIS layer was derived from the 12-Digit National Watershed Boundary Database (WBD) at 1:24,000 for EPA Region 2 and...

  14. Tau hadronic branching ratios

    CERN Document Server

    Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    From 64492 selected \\tau-pair events, produced at the Z^0 resonance, the measurement of the tau decays into hadrons from a global analysis using 1991, 1992 and 1993 ALEPH data is presented. Special emphasis is given to the reconstruction of photons and \\pi^0's, and the removal of fake photons. A detailed study of the systematics entering the \\pi^0 reconstruction is also given. A complete and consistent set of tau hadronic branching ratios is presented for 18 exclusive modes. Most measurements are more precise than the present world average. The new level of precision reached allows a stringent test of \\tau-\\mu universality in hadronic decays, g_\\tau/g_\\mu \\ = \\ 1.0013 \\ \\pm \\ 0.0095, and the first measurement of the vector and axial-vector contributions to the non-strange hadronic \\tau decay width: R_{\\tau ,V} \\ = \\ 1.788 \\ \\pm \\ 0.025 and R_{\\tau ,A} \\ = \\ 1.694 \\ \\pm \\ 0.027. The ratio (R_{\\tau ,V} - R_{\\tau ,A}) / (R_{\\tau ,V} + R_{\\tau ,A}), equal to (2.7 \\pm 1.3) \\ \\%, is a measure of the importance of Q...

  15. Grays River Watershed Geomorphic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R

    2005-04-30

    This investigation, completed for the Pacific Northwest National Laboratory (PNNL), is part of the Grays River Watershed and Biological Assessment commissioned by Bonneville Power Administration under project number 2003-013-00 to assess impacts on salmon habitat in the upper Grays River watershed and present recommendations for habitat improvement. This report presents the findings of the geomorphic assessment and is intended to support the overall PNNL project by evaluating the following: The effects of historical and current land use practices on erosion and sedimentation within the channel network The ways in which these effects have influenced the sediment budget of the upper watershed The resulting responses in the main stem Grays River upstream of State Highway 4 The past and future implications for salmon habitat.

  16. The fire-walker's high: affect and physiological responses in an extreme collective ritual.

    Science.gov (United States)

    Fischer, Ronald; Xygalatas, Dimitris; Mitkidis, Panagiotis; Reddish, Paul; Tok, Penny; Konvalinka, Ivana; Bulbulia, Joseph

    2014-01-01

    How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates) and self-reported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers), low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers) and spectators (unrelated/unknown to the fire-walkers). We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual.

  17. The fire-walker's high: affect and physiological responses in an extreme collective ritual.

    Directory of Open Access Journals (Sweden)

    Ronald Fischer

    Full Text Available How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates and self-reported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers, low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers and spectators (unrelated/unknown to the fire-walkers. We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual.

  18. Sex difference in attractiveness perceptions of strong and weak male walkers.

    Science.gov (United States)

    Fink, Bernhard; André, Selina; Mines, Johanna S; Weege, Bettina; Shackelford, Todd K; Butovskaya, Marina L

    2016-11-01

    Men and women accurately assess male physical strength from facial and body morphology cues. Women's assessments of male facial attractiveness, masculinity, and dominance correlate positively with male physical strength. A positive relationship also has been reported between physical strength and attractiveness of men's dance movements. Here, we investigate men's and women's attractiveness, dominance, and strength assessments from brief samples of male gait. Handgrip strength (HGS) was measured in 70 heterosexual men and their gait was motion-captured. Men and women judged 20 precategorized strong (high HGS) and weak (low HGS) walkers on attractiveness, dominance, and strength, and provided a measure of their own HGS. Both men and women judged strong walkers higher on dominance and strength than weak walkers. Women but not men judged strong walkers more attractive than weak walkers. These effects were independent of observers' physical strength. Male physical strength is conveyed not only through facial and body morphology, but also through body movements. We discuss our findings with reference to studies suggesting that physical strength provides information about male quality in contexts of inter- and intrasexual selection. Am. J. Hum. Biol. 28:913-917, 2016. © 2016Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. Watershed Education for Broadcast Meteorologists

    Science.gov (United States)

    Lamos, J. P.; Sliter, D.; Espinoza, S.; Spangler, T. C.

    2006-12-01

    The National Environmental Education and Training Organization (NEETF) published a report in 2005 that summarized the findings of ten years of NEETF and Roper Research. The report stated, "Our years of data from Roper surveys show a persistent pattern of environmental ignorance even among the most educated and influential members of society." Market research has also shown that 80% of television viewers list the weather as the primary reason for watching the local news. Broadcast meteorologists, with a broader understanding of environmental and related sciences have an opportunity to use their weathercasts to inform the public about the environment and the factors that influence environmental health. As "station scientists," broadcast meteorologists can use the weather, and people's connection to it, to broaden their understanding of the environment they live in. Weather and watershed conditions associated with flooding and drought have major human and environmental impacts. Increasing the awareness of the general public about basic aspects of the hydrologic landscape can be an important part of mitigating the adverse effects of too much or too little precipitation, and of protecting the environment as well. The concept of a watershed as a person's natural neighborhood is a very important one for understanding hydrologic and environmental issues. Everyone lives in a watershed, and the health of a watershed is the result of the interplay between weather and human activity. This paper describes an online course to give broadcast meteorologists a basic understanding of watersheds and how watersheds are impacted by weather. It discusses how to convey watershed science to a media- savvy audience as well as how to model the communication of watershed and hydrologic concepts to the public. The course uses a narrative, story-like style to present its content. It is organized into six short units of instruction, each approximately 20 minutes in duration. Each unit is

  20. Multiagent distributed watershed management

    Science.gov (United States)

    Giuliani, M.; Castelletti, A.; Amigoni, F.; Cai, X.

    2012-04-01

    Deregulation and democratization of water along with increasing environmental awareness are challenging integrated water resources planning and management worldwide. The traditional centralized approach to water management, as described in much of water resources literature, is often unfeasible in most of the modern social and institutional contexts. Thus it should be reconsidered from a more realistic and distributed perspective, in order to account for the presence of multiple and often independent Decision Makers (DMs) and many conflicting stakeholders. Game theory based approaches are often used to study these situations of conflict (Madani, 2010), but they are limited to a descriptive perspective. Multiagent systems (see Wooldridge, 2009), instead, seem to be a more suitable paradigm because they naturally allow to represent a set of self-interested agents (DMs and/or stakeholders) acting in a distributed decision process at the agent level, resulting in a promising compromise alternative between the ideal centralized solution and the actual uncoordinated practices. Casting a water management problem in a multiagent framework allows to exploit the techniques and methods that are already available in this field for solving distributed optimization problems. In particular, in Distributed Constraint Satisfaction Problems (DCSP, see Yokoo et al., 2000), each agent controls some variables according to his own utility function but has to satisfy inter-agent constraints; while in Distributed Constraint Optimization Problems (DCOP, see Modi et al., 2005), the problem is generalized by introducing a global objective function to be optimized that requires a coordination mechanism between the agents. In this work, we apply a DCSP-DCOP based approach to model a steady state hypothetical watershed management problem (Yang et al., 2009), involving several active human agents (i.e. agents who make decisions) and reactive ecological agents (i.e. agents representing

  1. Robust Redundant Input Reliable Tracking Control for Omnidirectional Rehabilitative Training Walker

    Directory of Open Access Journals (Sweden)

    Ping Sun

    2014-01-01

    Full Text Available The problem of robust reliable tracking control on the omnidirectional rehabilitative training walker is examined. The new nonlinear redundant input method is proposed when one wheel actuator fault occurs. The aim of the study is to design an asymptotically stable controller that can guarantee the safety of the user and ensure tracking on a training path planned by a physical therapist. The redundant degrees of freedom safety control and the asymptotically zero state detectable concept of the walker are presented, the model of redundant degree is constructed, and the property of center of gravity constant shift is obtained. A controller that can satisfy asymptotic stability is obtained using a common Lyapunov function for admissible uncertainties resulting from an actuator fault. Simulation results confirm the effectiveness of the proposed method and verify that the walker can provide safe sequential motion when one wheel actuator is at fault.

  2. Scaling Behaviors of Branched Polymers

    CERN Document Server

    Aoki, H; Kawai, H; Kitazawa, Y; Aoki, Hajime; Iso, Satoshi; Kawai, Hikaru; Kitazawa, Yoshihisa

    2000-01-01

    We study the thermodynamic behavior of branched polymers. We first study random walks in order to clarify the thermodynamic relation between the canonical ensemble and the grand canonical ensemble. We then show that correlation functions for branched polymers are given by those for $\\phi^3$ theory with a single mass insertion, not those for the $\\phi^3$ theory themselves. In particular, the two-point function behaves as $1/p^4$, not as $1/p^2$, in the scaling region. This behavior is consistent with the fact that the Hausdorff dimension of the branched polymer is four.

  3. Continuous-state branching processes

    CERN Document Server

    Li, Zenghu

    2012-01-01

    These notes were used in a short graduate course on branching processes the author gave in Beijing Normal University. The following main topics are covered: scaling limits of Galton--Watson processes, continuous-state branching processes, extinction probabilities, conditional limit theorems, decompositions of sample paths, martingale problems, stochastic equations, Lamperti's transformations, independent and dependent immigration processes. Some of the results are simplified versions of those in the author's book "Measure-valued branching Markov processes" (Springer, 2011). We hope these simplified results will set out the main ideas in an easy way and lead the reader to a quick access of the subject.

  4. Walker Community Library: building underground to serve neighborhood needs. [Minneapolis

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, D.J.

    1980-09-01

    A branch library in Minneapolis was constructed underground in order to meet community needs for public open areas and affordable library space. A review of the site selection and building-design processes reveals a long-standing interaction between the library board, residents of the neighborhood, and consultants to develop a consensus. The money saved by reducing the land area needed for a single-story building more than offset the higher construction costs of roof-top parking. Energy savings are estimated at a 40 percent reduction of the present above-ground facility. The pedestrian terrace connects with an existing mall and provides a setting for neighborhood activities. 6 figures. (DCK)

  5. Empowering and Assisting Natural Empowering and Assisting Natural Human Mobility: The Simbiosis Walker

    Directory of Open Access Journals (Sweden)

    Anselmo Frizera-Neto

    2011-08-01

    Full Text Available This paper presents the complete development of the Simbiosis Smart Walker. The device is equipped with a set of sensor subsystems to acquire user-machine interaction forces and the temporal evolution of user's feet during gait. The authors present an adaptive filtering technique used for the identification and separation of different components found on the human-machine interaction forces. This technique allowed isolating the components related with the navigational commands and developing a Fuzzy logic controller to guide the device. The Smart Walker was clinically validated at the Spinal Cord Injury Hospital of Toledo - Spain, presenting great acceptability by spinal chord injury patients and clinical staff.

  6. Test pilots 1962 - Armstrong, Walker, Dana, Peterson, McKay, Thompson, Butchart

    Science.gov (United States)

    1962-01-01

    The research pilots at what in 1962 was called the Flight Research Center standing in front of the X-1E. They are (left to right) Neil Armstrong, Joe Walker, Bill Dana, Bruce Peterson, Jack McKay, Milt Thompson, and Stan Butchart. of the group, Armstrong, Walker, Dana, McKay and Thompson all flew the X-15. Bruce Peterson flew the M2-F2 and HL-10 lifting bodies, while Stan Butchart was the B-29 drop plane pilot for many of the D-558-II and X-1 series research aircraft.

  7. Viscous Cosmology and Thermodynamics of Apparent Horizon in Modified Friedman-Robertson-Walkers Universe

    Science.gov (United States)

    Sadeghi, J.; Naji, J.; Vaez, H.; Khanpour, B.

    2014-09-01

    In this paper, we write modified Friedman-Robertson-Walkers (FRW) equation in the form of first law of thermodynamics at the apparent horizon. We consider the universe filled with the viscous fluid. Here we employ the general expression of temperature gravity and entropy at the apparent horizon of FRW universe and obtain the generalized first law of thermodynamics at the special condition for the modified FRW equation. The generalized first law of thermodynamics help us to arrange the α 1, α 2, β 1 and β 2 in modified Friedman-Robertson-Walkers equation.

  8. MORPHOLOGICAL ASPECTS OF Azochis gripusalis WALKER, 1859 (PYRAUSTIDAE - LEPIDOPTERA ASPECTOS MORFOLÓGICOS DA Azochis gripusalis Walker, 1859 (PYRAUSTIDAE - LEPIDOPTERA

    Directory of Open Access Journals (Sweden)

    Antônio Henrique Garcia

    2007-09-01

    Full Text Available

    For the purpose of understanding the external morphology of the adult of the Azochis gripusalis Walker, 1859 (Pyraustidae - Lepidoptera, a study was made of the head in dorsal, ventral, front, back and lateral views, of the thorax in dorsal, ventral and lateral views, of the front and back wings, of the prothoracic, mesothoracic and metathoracic legs, and of the abdomen in lateral view. The Azochis gripusalis is known by its large, dark ocelli; the sucking pump is well developed. The maxillary palps (feelers are small; the labial ones along with the middle segment are larger than the other segments. The thorax is straw-yellow with groups of shiny, light gray scales. The prothorax is very restricted in size. The mesothorax is larger than the prothorax and the metathorax put together. The front wings are triangular, shiny straw-yellow, with groups of dark brown scales arranged obliquely, forming isolated dark spots, measuring from 13 to 16 mm in length and having 13 veins all of which, with the exception of 3A, touch the edge of the wing.  The veins R¹, R² and R5 emerge directly from the discoidal cavity. R³ and R4 at the vertex of the wing are slightly bent downward. R², R³ and R4 form a trident (crotch. The back wings are semi-elliptcal, shiny straw-yellow, with groups of dark, irregular scales, and have 10 veins, all of which touch the edge of the wing. R², R³, R4 and R5 are fused. The discoidal cavity is open. Cu¹ emerges from the back angle of the discoidal cavity. 1A and 2A are fused at the base. The anal veins touch the edge of the wing. The wings, when resting, remain partially open. The legs display tibial spurs arranged according to the formula 0-2-4, respectively. The abdomen, dorsally, is shiny straw-yel1ow, with groups of slightly darkened scales between the segments. Eight segments are clearly distinguished. The sixth segment is slightly bent upward; nine and

  9. Ecological effects of contaminants in McCoy Branch, 1989-1990

    Energy Technology Data Exchange (ETDEWEB)

    Ryon, M.G. [ed.

    1992-01-01

    The 1984 Hazardous and Solid Waste Amendments to the Resource Conservation and Recovery Act (RCRA) required assessment of all current and former solid waste management units. Such a RCRA Facility Investigation (RFI) was required of the Y-12 Plant for their Filled Coal Ash Pond on McCoy Branch. Because the disposal of coal ash in the ash pond, McCoy Branch, and Rogers Quarry was not consistent with the Tennessee Water Quality Act, several remediation steps were implemented or planned for McCoy Branch to address disposal problems. The McCoy Branch RFI plan included provisions for biological monitoring of the McCoy Branch watershed. The objectives of the biological monitoring were to: (1) document changes in biological quality of McCoy Branch after completion of a pipeline and after termination of all discharges to Rogers Quarry, (2) provide guidance on the need for additional remediation, and (3) evaluate the effectiveness of implemented remedial actions. The data from the biological monitoring program will also determine if the classified uses, as identified by the State of Tennessee, of McCoy Branch are being protected and maintained. This report discusses results from toxicity monitoring of snails fish community assessment, and a Benthic macroinvertebrate community assessment.

  10. Ecological effects of contaminants in McCoy Branch, 1989-1990

    Energy Technology Data Exchange (ETDEWEB)

    Ryon, M.G. (ed.)

    1992-01-01

    The 1984 Hazardous and Solid Waste Amendments to the Resource Conservation and Recovery Act (RCRA) required assessment of all current and former solid waste management units. Such a RCRA Facility Investigation (RFI) was required of the Y-12 Plant for their Filled Coal Ash Pond on McCoy Branch. Because the disposal of coal ash in the ash pond, McCoy Branch, and Rogers Quarry was not consistent with the Tennessee Water Quality Act, several remediation steps were implemented or planned for McCoy Branch to address disposal problems. The McCoy Branch RFI plan included provisions for biological monitoring of the McCoy Branch watershed. The objectives of the biological monitoring were to: (1) document changes in biological quality of McCoy Branch after completion of a pipeline and after termination of all discharges to Rogers Quarry, (2) provide guidance on the need for additional remediation, and (3) evaluate the effectiveness of implemented remedial actions. The data from the biological monitoring program will also determine if the classified uses, as identified by the State of Tennessee, of McCoy Branch are being protected and maintained. This report discusses results from toxicity monitoring of snails fish community assessment, and a Benthic macroinvertebrate community assessment.

  11. 77 FR 67811 - Porter-Walker LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for...

    Science.gov (United States)

    2012-11-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Porter-Walker LLC; Supplemental Notice That Initial Market-Based Rate Filing...-referenced proceeding of Porter-Walker LLC's application for market-based rate authority, with an...

  12. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  13. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter;

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  14. Novel side branch ostial stent.

    Science.gov (United States)

    Chen, Shao-Liang; Lv, Shu-Zheng; Kwan, Tak W

    2009-04-01

    Bifurcation lesions are technically challenging and plagued by a high incidence of restenosis, especially at the side branch orifice, which results in a more frequent need for revascularization during the follow-up period. This report discusses two clinical experiences with a novel side branch ostial stent, the BIGUARD stent, designed for the treatment of bifurcation lesions; procedural success with no in-hospital complications was observed in types IVb and Ia lesions.

  15. Structural Mechanics and Dynamics Branch

    Science.gov (United States)

    Stefko, George

    2003-01-01

    The 2002 annual report of the Structural Mechanics and Dynamics Branch reflects the majority of the work performed by the branch staff during the 2002 calendar year. Its purpose is to give a brief review of the branch s technical accomplishments. The Structural Mechanics and Dynamics Branch develops innovative computational tools, benchmark experimental data, and solutions to long-term barrier problems in the areas of propulsion aeroelasticity, active and passive damping, engine vibration control, rotor dynamics, magnetic suspension, structural mechanics, probabilistics, smart structures, engine system dynamics, and engine containment. Furthermore, the branch is developing a compact, nonpolluting, bearingless electric machine with electric power supplied by fuel cells for future "more electric" aircraft. An ultra-high-power-density machine that can generate projected power densities of 50 hp/lb or more, in comparison to conventional electric machines, which generate usually 0.2 hp/lb, is under development for application to electric drives for propulsive fans or propellers. In the future, propulsion and power systems will need to be lighter, to operate at higher temperatures, and to be more reliable in order to achieve higher performance and economic viability. The Structural Mechanics and Dynamics Branch is working to achieve these complex, challenging goals.

  16. Radiation effects on branched polysilanes

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, K.; Seki, S.; Tagawa, S. [Osaka Univ., Ibaraki (Japan). Inst. of Scientific and Industrial Research; Shibata, H.; Iwai, T. [Tokyo Univ. (Japan). Research Center for Nuclear Science and Technology

    2000-03-01

    We observed crosslinking and scission caused by gamma radiation in linear and branched polysilanes which have from 5% to 33% of the branching points. The crosslinking reactions become predominant for the irradiation with branching density increasing. The cleavage did not take place exclusively at the branching points and branching polysilanes are sensitive to radiation extraordinary as compared with linear polysilane from a careful study of the radiolysis products of a series of polysilanes. This is due to the increasing Si {center_dot} contributing to the crosslinking reaction and that they are not resonance-stabilized by double bonds as the reaction mechanism in the irradiated polysilanes. However, the gelation curve in linear PMPS irradiated by 2 MeV He{sup +} is almost consistent with that in branching PMPS, indicating that the size of chemical track is responsible for the gel fraction. The crosslinking G value for high molecular weight PMPS irradiated by 2 MeV He{sup +} was drastically decreased as compared with that for low molecular weight. It suggests that there are a large number of intramolecular crosslinking points for high molecular weight PMPS. (author)

  17. Principles of branch formation and branch patterning in Hydrozoa.

    Science.gov (United States)

    Berking, Stefan

    2006-01-01

    The freshwater polyp Hydra produces buds which separate from the parent. Other Hydrozoa produce branches which remain connected to the parent, thus forming a colony. Some Hydrozoa grow by means of an organ that is like a shoot apical meristem. Others display a sympodial type of growth. In this article, I propose that these different types of branches are organized by a common pattern-forming system. This system has self-organizing properties. It causes branch tip formation and is kept active in the tip when the tip finally differentiates into a hypostome of a polyp. The system does not cause structure formation directly but rather, determines a tissue property called positional value, in such a way that a gradient of values forms in the tissue of the bud or branch. The local value determines the local morphodynamic processes, including differentiation of the hypostome (highest positional value), tentacles and basal disc and of the exoskeleton pattern along the shoot. A high positional value favors the onset of a new self-organizing process and by lateral inhibition, such a process prevents the initiation of a further process in its surroundings. Small quantitative differences in the range of the signals involved determine whether a bud or a branch forms and whether monopodial and sympodial growth follows.

  18. A New Controller for a Smart Walker Based on Human-Robot Formation

    Directory of Open Access Journals (Sweden)

    Carlos Valadão

    2016-07-01

    Full Text Available This paper presents the development of a smart walker that uses a formation controller in its displacements. Encoders, a laser range finder and ultrasound are the sensors used in the walker. The control actions are based on the user (human location, who is the actual formation leader. There is neither a sensor attached to the user’s body nor force sensors attached to the arm supports of the walker, and thus, the control algorithm projects the measurements taken from the laser sensor into the user reference and, then, calculates the linear and angular walker’s velocity to keep the formation (distance and angle in relation to the user. An algorithm was developed to detect the user’s legs, whose distances from the laser sensor provide the information necessary to the controller. The controller was theoretically analyzed regarding its stability, simulated and validated with real users, showing accurate performance in all experiments. In addition, safety rules are used to check both the user and the device conditions, in order to guarantee that the user will not have any risks when using the smart walker. The applicability of this device is for helping people with lower limb mobility impairments.

  19. Swing-Leg Retraction for Limit Cycle Walkers Improves Disturbance Rejection

    NARCIS (Netherlands)

    Hobbelen, D.G.E.; Wisse, M.

    2008-01-01

    Limit cycle walkers are bipeds that exhibit a stable cyclic gaitwithout requiring local controllability at all times during gait. A well-known example of limit cycle walking is McGeer’s “passive dynamic walking,” but the concept expands to actuated bipeds as involved in this study. One of the stabil

  20. Moebius syndrome with Dandy-Walker variant and agenesis of corpus callosum

    Directory of Open Access Journals (Sweden)

    Jomol Sara John

    2013-01-01

    Full Text Available Moebius syndrome is a rare congenital neurological disorder. The most frequent mode of presentation is facial diplegia with bilateral lateral rectus palsy, but there are variations. Here, we report a rare case of Moebius syndrome in a 15-month-old child with unilateral facial palsy, bilateral abducens nerve palsy with Dandy Walker variant, and complete agenesis of corpus callosum.

  1. Finite-Sample Bias Propagation in Autoregressive Estimation With the Yule–Walker Method

    NARCIS (Netherlands)

    Broersen, P.M.T.

    2009-01-01

    The Yule-Walker (YW) method for autoregressive (AR) estimation uses lagged-product (LP) autocorrelation estimates to compute an AR parametric spectral model. The LP estimates only have a small triangular bias in the estimated autocorrelation function and are asymptotically unbiased. However, using t

  2. [Stress parameters and behaviour of horses in walkers with and without the use of electricity].

    Science.gov (United States)

    Giese, C; Gerber, V; Howald, M; Bachmann, I; Burger, D

    2014-04-01

    In order to investigate stress responses of horses in walkers with and without electricity, 12 horses were trained during 3 weeks in a horse walker with and without the use of electricity (3.7 kV). To evaluate the stress response, cortisol levels in the blood were measured, the heart rate was monitored using the Polar® system and the behaviour was evaluated. Neither the cortisol levels nor the heart rates showed any relevant statistically significant difference between horses moved in the horse walker with or without the use of electricity. The highest cortisol levels and heart rates were recorded during the first week (habituation period). A significant difference could be observed regarding spontaneous compartment changes: while this happened mainly during the first week and before the first use of electricity, no horses changed compartments in the periods when electricity was used and thereafter. The results of this study indicate that the use of electricity in the horse walker does not seem to cause significant detectable stress in the horses.

  3. Sex Differences in Moral Reasoning: Response to Walker's (1984) Conclusion That There Are None.

    Science.gov (United States)

    Baumrind, Diana

    1986-01-01

    Takes issue with Lawrence Walker's literature review on developmental and individual differences in moral reasoning which found no consistent evidence for sex differences in moral development. Argues instead that the source and specific nature of these differences have yet to be established. (HOD)

  4. Seeing the Sky through Hubble's Eye: The COSMOS SkyWalker

    Science.gov (United States)

    Jahnke, K.; Sánchez, S. F.; Koekemoer, A.

    2006-08-01

    Large, high-resolution space-based imaging surveys produce a volume of data that is difficult to present to the public in a comprehensible way. While megapixel-sized images can still be printed out or downloaded via the World Wide Web, this is no longer feasible for images with 109 pixels (e.g., the Hubble Space Telescope Advanced Camera for Surveys [ACS] images of the Galaxy Evolution from Morphology and SEDs [GEMS] project) or even 1010 pixels (for the ACS Cosmic Evolution Survey [COSMOS]). We present a Web-based utility called the COSMOS SkyWalker that allows viewing of the huge ACS image data set, even through slow Internet connections. Using standard HTML and JavaScript, the application successively loads only those portions of the image at a time that are currently being viewed on the screen. The user can move within the image by using the mouse or interacting with an overview image. Using an astrometrically registered image for the COSMOS SkyWalker allows the display of calibrated world coordinates for use in science. The SkyWalker ``technique'' can be applied to other data sets. This requires some customization, notably the slicing up of a data set into small (e.g., 2562 pixel) subimages. An advantage of the SkyWalker is the use of standard Web browser components; thus, it requires no installation of any software and can therefore be viewed by anyone across many operating systems.

  5. Sex Differences in Moral Reasoning: Response to Walker's (1984) Conclusion That There Are None.

    Science.gov (United States)

    Baumrind, Diana

    1986-01-01

    Takes issue with Lawrence Walker's literature review on developmental and individual differences in moral reasoning which found no consistent evidence for sex differences in moral development. Argues instead that the source and specific nature of these differences have yet to be established. (HOD)

  6. Collateral Damage: Veterans and Domestic Violence in Mari Sandoz's "The Tom-Walker"

    Science.gov (United States)

    Bahr, Kathy

    2010-01-01

    "The Tom-Walker" combines the best of Sandoz's realism with her worst attempts at moralizing. Unable to divine exactly what political configuration right-wing post-World War II sentiments might take, Sandoz nevertheless feared a fascist uprising in this country. Perhaps because these concerns dominated her thoughts at the time, she allowed her…

  7. Origin of the Pinenuts and Other Stories from the Walker River Paiute Reservation.

    Science.gov (United States)

    George, Wuzzie; And Others

    The four stories gathered from Paiute Tribal Elders through the Ethnic Heritage Studies Program have been changed from the original telling insofar as it was necessary to make them suitable to the elementary level. The short stories, meant to be spoken orally, relate how the Walker Lake Paiutes got pinenuts away from the Owyhee area ("Origin…

  8. High Performance Sustainable School Design: Roy Lee Walker Elementary, McKinney, Texas.

    Science.gov (United States)

    SHW Group, Inc., Dallas, TX.

    This document describes the sustainable features of the Roy Lee Walker Elementary School (Texas), a prototype "Eco Education" school that blends the physical environment with the student learning process while protecting the site. The document also presents the process of integrating sustainability criteria in all phases of the school's…

  9. Two Thirds of Forest Walkers with Japanese Cedar Pollinosis Visit Forests even During the Pollen Season

    Directory of Open Access Journals (Sweden)

    Emi Morita

    2009-01-01

    Conclusions: These results revealed that two thirds of forest walkers who had experienced JCP visited forests even during the pollen season. This indicates the further need for public service announcements informing people with JCP that the risk of pollen exposure and subsequent JCP reaction is increased by visiting forested areas during the pollen season.

  10. Robertson-Walker cosmological models with perfect fluid in general relativity

    Institute of Scientific and Technical Information of China (English)

    Rishi Kumar Tiwari

    2011-01-01

    Einstein's field equations with variable gravitational and cosmological constants are considered in the presence of perfect fluid for a Robertson-Walker universe by assuming the cosmological term to be proportional to R-m (R is a scale factor and m is a constant). A variety of solutions is presented. The physical significance of the cosmological models has also been discussed.

  11. Interinstrument Consistency of the Yamax Digi-Walker Pedometer in Elementary School-Aged Children

    Science.gov (United States)

    Barfield, J. P.; Rowe, David A.; Michael, Timothy J.

    2004-01-01

    A pedometer is a practical, inexpensive tool used to measure physical activity. Bassett et al. (1996) found that interinstrument consistency of the Yamax Digi-Walker was higher than four other pedometers when measuring distance walked in adults. The purpose of this study was to investigate the interinstrument consistency of the Yamax pedometer in…

  12. Promoting Ambulation Responses among Children with Multiple Disabilities through Walkers and Microswitches with Contingent Stimuli

    Science.gov (United States)

    Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Oliva, Doretta; Smaldone, Angela; La Martire, Maria L.; Stasolla, Fabrizio; Castagnaro, Francesca; Groeneweg, Jop

    2010-01-01

    Children with severe or profound intellectual and motor disabilities often present problems of balance and ambulation and spend much of their time sitting or lying, with negative consequences for their development and social status. Recent research has shown the possibility of using a walker (support) device and microswitches with preferred…

  13. Stick-slip actuation of electrostatic stepper micropositioners for data storage-the µWalker

    NARCIS (Netherlands)

    Patrascu, M.; Stramigioli, Stefano

    2005-01-01

    This paper is about the /spl mu/Walker, an electrostatic stepper motor mainly intended for positioning the data probes with respect to the storage medium in a data storage device. It can deliver forces up to 1.7 mN for ranges as large as 140 /spl mu/m. Controlling the stick-slip effects at the slidi

  14. Walkers' Perspectives on Nature Management Strategies: Nature Restoration in a National Park

    NARCIS (Netherlands)

    Marwijk, van R.B.M.

    2008-01-01

    Leisure practices and public space, third chapter. Ramona van Marwijk is part of a bigger research projecton time-space behavioural patterns in a landscape where nature development and recreational values are combined. She is interested in what walkers in the Dutch National Park Dwingelderveld think

  15. A New Controller for a Smart Walker Based on Human-Robot Formation

    Science.gov (United States)

    Valadão, Carlos; Caldeira, Eliete; Bastos-Filho, Teodiano; Frizera-Neto, Anselmo; Carelli, Ricardo

    2016-01-01

    This paper presents the development of a smart walker that uses a formation controller in its displacements. Encoders, a laser range finder and ultrasound are the sensors used in the walker. The control actions are based on the user (human) location, who is the actual formation leader. There is neither a sensor attached to the user’s body nor force sensors attached to the arm supports of the walker, and thus, the control algorithm projects the measurements taken from the laser sensor into the user reference and, then, calculates the linear and angular walker’s velocity to keep the formation (distance and angle) in relation to the user. An algorithm was developed to detect the user’s legs, whose distances from the laser sensor provide the information necessary to the controller. The controller was theoretically analyzed regarding its stability, simulated and validated with real users, showing accurate performance in all experiments. In addition, safety rules are used to check both the user and the device conditions, in order to guarantee that the user will not have any risks when using the smart walker. The applicability of this device is for helping people with lower limb mobility impairments. PMID:27447634

  16. Statement of Facts for 1977 City-Wide Mock Trial Competitions. Walker Thomas v. Sam Nomad.

    Science.gov (United States)

    National Inst. for Citizen Education in the Law, Washington, DC.

    Prepared by the District of Columbia Street Law Project for its annual city-wide mock trial competition, this instructional handout provides material for a civil case over an automobile accident. Walker Thomas is suing Sam Nomad for damages that resulted from a collision, for which both parties blame the other. The handout clarifies the laws and…

  17. On Maximal Surfaces in Certain Non-Flat 3-Dimensional Robertson-Walker Spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Alfonso, E-mail: aromero@ugr.es [Universidad de Granada, Departamento de Geometria y Topologia (Spain); Rubio, Rafael M., E-mail: rmrubio@uco.es [Universidad de Cordoba, Departamento de Matematicas, Campus de Rabanales (Spain)

    2012-09-15

    An upper bound for the integral, on a geodesic disc, of the squared length of the gradient of a distinguished function on any maximal surface in certain non-flat 3-dimensional Robertson-Walker spacetimes is obtained. As an application, a new proof of a known Calabi-Bernstein's theorem is given.

  18. A Watershed Integrity Definition and Assessment Approach to Support Strategic Management of Watersheds

    Science.gov (United States)

    Although defined hydrologically as a drainage basin, watersheds are systems that physically link the individual social and ecological attributes that comprise them. Hence the structure, function, and feedback systems of watersheds are dependent on interactions between these soci...

  19. A Watershed Integrity Definition and Assessment Approach to Support Strategic Management of Watersheds

    Science.gov (United States)

    Although defined hydrologically as a drainage basin, watersheds are systems that physically link the individual social and ecological attributes that comprise them. Hence the structure, function, and feedback systems of watersheds are dependent on interactions between these soci...

  20. Watershed Fact Sheet: Improving Utah's Water Quality, Upper Bear River Watershed

    OpenAIRE

    2012-01-01

    The Upper Watershed of the Bear River Basin extends from the river's headwaters to Pixley Dam in Wyoming. This is the largest watershed in the Bear River Basin, with an area of about 2,000 square miles.

  1. A gait stability investigation into FES-assisted paraplegic walking based on the walker tipping index

    Science.gov (United States)

    Ming, Dong; Bai, Yanru; Liu, Xiuyun; Qi, Hongzhi; Cheng, Longlong; Wan, Baikun; Hu, Yong; Wong, Yatwa; Luk, Keith D. K.; Leong, John C. Y.

    2009-12-01

    The gait outcome measures used in clinical trials of paraplegic locomotor training determine the effectiveness of improved walking function assisted by the functional electrical stimulation (FES) system. Focused on kinematic, kinetic or physiological changes of paraplegic patients, traditional methods cannot quantify the walking stability or identify the unstable factors of gait in real time. Up until now, the published studies on dynamic gait stability for the effective use of FES have been limited. In this paper, the walker tipping index (WTI) was used to analyze and process gait stability in FES-assisted paraplegic walking. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the frame of the walker. This system collected force information for the handle reaction vector between the patient's upper extremities and the walker during the walking process; the information was then converted into walker tipping index data, which is an evaluation indicator of the patient's walking stability. To demonstrate the potential usefulness of WTI in gait analysis, a preliminary clinical trial was conducted with seven paraplegic patients who were undergoing FES-assisted walking training and seven normal control subjects. The gait stability levels were quantified for these patients under different stimulation patterns and controls under normal walking with knee-immobilization through WTI analysis. The results showed that the walking stability in the FES-assisted paraplegic group was worse than that in the control subject group, with the primary concern being in the anterior-posterior plane. This new technique is practical for distinguishing useful gait information from the viewpoint of stability, and may be further applied in FES-assisted paraplegic walking rehabilitation.

  2. Extraction of user's navigation commands from upper body force interaction in walker assisted gait

    Directory of Open Access Journals (Sweden)

    Pons José L

    2010-08-01

    Full Text Available Abstract Background The advances in technology make possible the incorporation of sensors and actuators in rollators, building safer robots and extending the use of walkers to a more diverse population. This paper presents a new method for the extraction of navigation related components from upper-body force interaction data in walker assisted gait. A filtering architecture is designed to cancel: (i the high-frequency noise caused by vibrations on the walker's structure due to irregularities on the terrain or walker's wheels and (ii the cadence related force components caused by user's trunk oscillations during gait. As a result, a third component related to user's navigation commands is distinguished. Results For the cancelation of high-frequency noise, a Benedict-Bordner g-h filter was designed presenting very low values for Kinematic Tracking Error ((2.035 ± 0.358·10-2 kgf and delay ((1.897 ± 0.3697·101ms. A Fourier Linear Combiner filtering architecture was implemented for the adaptive attenuation of about 80% of the cadence related components' energy from force data. This was done without compromising the information contained in the frequencies close to such notch filters. Conclusions The presented methodology offers an effective cancelation of the undesired components from force data, allowing the system to extract in real-time voluntary user's navigation commands. Based on this real-time identification of voluntary user's commands, a classical approach to the control architecture of the robotic walker is being developed, in order to obtain stable and safe user assisted locomotion.

  3. Landscape characterization for watershed management

    Energy Technology Data Exchange (ETDEWEB)

    Hunsaker, C.T.; Jackson, B.L. [Oak Ridge National Lab., TN (United States); Schwartz, P.M. [Oak Ridge Institute for Science Education, Oak Ridge, TN (United States)

    1996-07-01

    Streams and rivers serve as integrators of terrestrial landscape characteristics and as recipients of pollutants from both the atmosphere and the land; thus, large rivers are especially good indicators of cumulative impacts. Landscape ecologists seek to better understand the relationships between landscape structure and ecosystem processes at various spatial scales. Understanding how scale, both data resolution and geographic extent, influences landscape characterization and how terrestrial processes affect water quality are critically important for model development and translation of research results from experimental watersheds to management of large drainage basins. Measures of landscape structure are useful to monitor change and assess the risks it poses to ecological resources. Many studies have shown that the proportion of different land uses within a watershed can account for some of the variability in surface water quality. Hunsaker and Levine showed that both proportion of land uses and the spatial pattern of land uses is important for characterizing and modeling water quality; however, proportion consistently accounted for the most variance (40% to 86%) across a range of watershed sizes (1000 to 1.35 million ha). The U.S. Environmental Protection Agency (EPA) is performing a demonstration of its Environmental Monitoring and Assessment Program (EMAP) for the Mid-Atlantic Region. One activity, the Mid-Atlantic Integrated Assessment, is designed as a collaborative initiative between EPA`s Office of Research and Development and EPA`s Region III.

  4. Photovoltaic measurements and performance branch

    Science.gov (United States)

    Asher, S. E.; Dippo, P.

    1990-05-01

    The Photovoltaic (PV) Measurements and Performance Branch of the Solar Energy Research Institute (SERI) provides comprehensive PV materials, device and component characterization, measurement, fabrication, and modeling research and support for the international PV research community in the context of the U.S. Department of Energy's PV m goals. The progress of the Branch is summarized. The seven technical sections present a succinct overview of the capabilities and accomplishments of each group in the Branch. The Branch is comprised of the following groups; Surface and Interface Analysis, Materials Characterization, Device Development, Electro-Optical Characterization, Cell Performance, Advanced Module Testing and Performance, and Surface and Interface Modification and Stability. The main research projects completed in FY 1989 are highlighted including measurements and tests of PV materials, cells, submodules and modules. The report contains a comprehensive bibliography of the more than 80 branch-originated journal and conference publications which were authored in collaboration with, or in support of, approximately 130 university, industrial, government, and in-house research groups.

  5. Elevation - LiDAR Survey Minnehaha Creek, MN Watershed

    Data.gov (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — LiDAR Bare-Earth Grid - Minnehaha Creek Watershed District. The Minnehaha Creek watershed is located primarily in Hennepin County, Minnesota. The watershed covers...

  6. Volunteer Watershed Health Monitoring by Local Stakeholders: New Mexico Watershed Watch

    Science.gov (United States)

    Fleming, William

    2003-01-01

    Volunteers monitor watershed health in more than 700 programs in the US, involving over 400,000 local stakeholders. New Mexico Watershed Watch is a student-based watershed monitoring program sponsored by the state's Department of Game and Fish which provides high school teachers and students with instruction on methods for water quality…

  7. Engaging Watershed Stakeholders for Cost-Effective Environmental Management Planning with "Watershed Manager"

    Science.gov (United States)

    Williams, Jeffery R.; Smith, Craig M.; Roe, Josh D.; Leatherman, John C.; Wilson, Robert M.

    2012-01-01

    "Watershed Manager" is a spreadsheet-based model that is used in extension education programs for learning about and selecting cost-effective watershed management practices to reduce soil, nitrogen, and phosphorus losses from cropland. It can facilitate Watershed Restoration and Protection Strategy (WRAPS) stakeholder groups' development…

  8. Engaging Watershed Stakeholders for Cost-Effective Environmental Management Planning with "Watershed Manager"

    Science.gov (United States)

    Williams, Jeffery R.; Smith, Craig M.; Roe, Josh D.; Leatherman, John C.; Wilson, Robert M.

    2012-01-01

    "Watershed Manager" is a spreadsheet-based model that is used in extension education programs for learning about and selecting cost-effective watershed management practices to reduce soil, nitrogen, and phosphorus losses from cropland. It can facilitate Watershed Restoration and Protection Strategy (WRAPS) stakeholder groups' development…

  9. Engaging Watershed Stakeholders for Cost-Effective Environmental Management Planning with "Watershed Manager"

    Science.gov (United States)

    Williams, Jeffery R.; Smith, Craig M.; Roe, Josh D.; Leatherman, John C.; Wilson, Robert M.

    2012-01-01

    "Watershed Manager" is a spreadsheet-based model that is used in extension education programs for learning about and selecting cost-effective watershed management practices to reduce soil, nitrogen, and phosphorus losses from cropland. It can facilitate Watershed Restoration and Protection Strategy (WRAPS) stakeholder groups' development of…

  10. Water and Poverty in Two Colombian Watersheds

    Directory of Open Access Journals (Sweden)

    Nancy Johnson

    2009-02-01

    Full Text Available Watersheds, especially in the developing world, are increasingly being managed for both environmental conservation and poverty alleviation. How complementary are these objectives? In the context of a watershed, the actual and potential linkages between land and water management and poverty are complex and likely to be very site specific and scale dependent. This study analyses the importance of watershed resources in the livelihoods of the poor in two watersheds in the Colombian Andes. Results of the participatory poverty assessment reveal significant decreases in poverty in both watersheds over the past 25 years, which was largely achieved by the diversification of livelihoods outside of agriculture. Water is an important resource for household welfare. However, opportunities for reducing poverty by increasing the quantity or quality of water available to the poor may be limited. While improved watershed management may have limited direct benefits in terms of poverty alleviation, there are important indirect linkages between watershed management and poverty, mainly through labour and service markets. The results suggest that at the level of the watershed the interests of the rich and the poor are not always in conflict over water. Sectoral as well as socio-economic differences define stakeholder groups in watershed management. The findings have implications for policymakers, planners and practitioners in various sectors involved in the implementation of integrated water resources management (IWRM.

  11. Community-Based Integrated Watershed Management

    Institute of Scientific and Technical Information of China (English)

    Li Qianxiang; Kennedy N.logbokwe; Li Jiayong

    2005-01-01

    Community-based watershed management is different from the traditional natural resources management. Traditional natural resources management is a way from up to bottom, but the community-based watershed management is from bottom to up. This approach focused on the joining of different stakeholders in integrated watershed management, especially the participation of the community who has been ignored in the past. The purpose of this paper is to outline some of the important basic definitions, concepts and operational framework for initiating community-based watershed management projects and programs as well as some successes and practical challenges associated with the approach.

  12. Multiple pathways regulate shoot branching

    Directory of Open Access Journals (Sweden)

    Catherine eRameau

    2015-01-01

    Full Text Available Shoot branching patterns result from the spatio-temporal regulation of axillary bud outgrowth. Numerous endogenous, developmental and environmental factors are integrated at the bud and plant levels to determine numbers of growing shoots. Multiple pathways that converge to common integrators are most probably involved. We propose several pathways involving not only the classical hormones auxin, cytokinins and strigolactones, but also other signals with a strong influence on shoot branching such as gibberellins, sugars or molecular actors of plant phase transition. We also deal with recent findings about the molecular mechanisms and the pathway involved in the response to shade as an example of an environmental signal controlling branching. We propose the TCP transcription factor TB1/BRC1 and the polar auxin transport stream in the stem as possible integrators of these pathways. We finally discuss how modeling can help to represent this highly dynamic system by articulating knowledges and hypothesis and calculating the phenotype properties they imply.

  13. Warped branches of flux compactifications

    CERN Document Server

    Lim, Yen-Kheng

    2012-01-01

    We consider Freund-Rubin-type compactifications which are described by (p+q)-dimensional Einstein gravity with a positive cosmological constant and a q-form flux. Using perturbative expansions of Kinoshita's ansatz for warped dS_pxS^q and AdS_pxS^q spacetimes, we obtain analytical solutions describing the warped branches and their respective phase spaces. These equations are given by inhomogeneous Gegenbauer differential equations which can be solved by the Green's function method. The requirement that the Green's functions are regular provides constraints which determine the structure of the phase space of the warped branches. We apply the perturbation results to calculate the thermodynamic variables for the warped dS_pxS^q branch. In particular, the first law of thermodynamics can be reproduced using this method.

  14. 30 CFR 56.6403 - Branch circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Branch circuits. 56.6403 Section 56.6403... Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits, each branch shall be equipped with a safety switch or equivalent method to isolate the circuits to be used....

  15. 30 CFR 57.6403 - Branch circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Branch circuits. 57.6403 Section 57.6403... Blasting-Surface and Underground § 57.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits, each branch shall be equipped with a safety switch or equivalent method to isolate...

  16. Experimental model of ultrasound thermotherapy in rats inoculated with Walker-236 tumor Modelo experimental de termoterapia ultrassônica em ratos inoculados com tumor de Walker-236

    Directory of Open Access Journals (Sweden)

    José Antonio Carlos Otaviano David Morano

    2011-01-01

    Full Text Available PURPOSE: To develop a model to evaluate the effects of focal pulsed ultrasound (US waves as a source of heat for treatment of murine subcutaneous implanted Walker tumor. METHODS: An experimental, controlled, comparative study was conducted. Twenty male Wistar rats (160-300 g randomized in 2 equal groups (G-1: Control and G-2: Hyperthermia were inoculated with Walker-256 carcinosarcoma tumor. After 5 days G-2 rats were submitted to 45ºC hyperthermia. Heat was delivered directly to the tumor by an ultrasound (US equipment (3 MHz frequency, 1,5W/cm³. Tumor temperature reached 45º C in 3 minutes and was maintained at this level for 5 minutes. Tumor volume was measured on days 5, 8, 11, 14 e 17 post inoculation in both groups. Unpaired t-test was used for comparison. POBJETIVO: Desenvolver um modelo para avaliar os efeitos do ultra-som focal pulsado como fonte de calor para o tratamento de tumores de Walker subcutâneos implantados em ratos. MÉTODOS: Um estudo experimental, controlado, comparativo foi realizado. Vinte ratos Wistar machos (160-300 g divididos em dois grupos (G-1: Controle e G-2: hipertermia foram inoculados com tumor de Walker carcinossarcoma-256. Após cinco dias os ratos do grupo G-2 ratos foram submetidos a hipertermia (45ºC. O calor foi aplicado diretamente no tumor por um equipamento de ultrassonografia (3 MHz, 1,5 W/cm³. A temperatura no tumor atingiu 45ºC em 3 minutos e foi mantida nesse nível por 5 minutos. O volume do tumor foi medido nos dias 5, 8, 11, 14 e 17 após a inoculação, em ambos os grupos. Teste t não pareado foi utilizado para comparação. P <0,05 foi considerado significante. RESULTADOS: O volume do tumor foi significativamente maior no 5º dia e diminuiu nos dias 11, 14 e 17 nos ratos tratados. Animais submetidos à hipertermia sobreviveram mais tempo que os animais do grupo controle. No 29º dia após a inoculação do tumor, 40% dos ratos do grupo controle e 77,78% dos ratos tratados com

  17. Strigolactone inhibition of shoot branching

    NARCIS (Netherlands)

    Gomez-Roldan, M.V.; Fermas, S.; Brewer, P.B.; Puech-Pages, V.; Dun, E.A.; Pillot, J.P.; Letisse, F.; Matusova, R.; Danoun, S.; Portais, J.C.; Bouwmeester, H.J.; Becard, G.; Beveridge, C.A.; Rameau, C.; Rochange, S.F.

    2008-01-01

    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence

  18. Strigolactone inhibition of shoot branching

    NARCIS (Netherlands)

    Gomez-Roldan, M.V.; Fermas, S.; Brewer, P.B.; Puech-Pages, V.; Dun, E.A.; Pillot, J.P.; Letisse, F.; Matusova, R.; Danoun, S.; Portais, J.C.; Bouwmeester, H.J.; Becard, G.; Beveridge, C.A.; Rameau, C.; Rochange, S.F.

    2008-01-01

    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence

  19. Cash efficiency for bank branches.

    Science.gov (United States)

    Cabello, Julia García

    2013-01-01

    Bank liquidity management has become a major issue during the financial crisis as liquidity shortages have intensified and have put pressure on banks to diversity and improve their liquidity sources. While a significant strand of the literature concentrates on wholesale liquidity generation and on the alternative to deposit funding, the management of an inventory of cash holdings within the banks' branches is also a relevant issue as any significant improvement in cash management at the bank distribution channels may have a positive effect in reducing liquidity tensions. In this paper, we propose a simple programme of cash efficiency for the banks' branches, very easy to implement, which conform to a set of instructions to be imposed from the bank to their branches. This model proves to significantly reduce cash holdings at branches thereby providing efficiency improvements in liquidity management. The methodology we propose is based on the definition of some stochastic processes combined with renewal processes, which capture the random elements of the cash flow, before applying suitable optimization programmes to all the costs involved in cash movements. The classical issue of the Transaction Demand for the Cash and some aspects of Inventory Theory are also present. Mathematics Subject Classification (2000) C02, C60, E50.

  20. Branching of keratin intermediate filaments.

    Science.gov (United States)

    Nafeey, Soufi; Martin, Ines; Felder, Tatiana; Walther, Paul; Felder, Edward

    2016-06-01

    Keratin intermediate filaments (IFs) are crucial to maintain mechanical stability in epithelial cells. Since little is known about the network architecture that provides this stiffness and especially about branching properties of filaments, we addressed this question with different electron microscopic (EM) methods. Using EM tomography of high pressure frozen keratinocytes, we investigated the course of several filaments in a branching of a filament bundle. Moreover we found several putative bifurcations in individual filaments. To verify our observation we also visualized the keratin network in detergent extracted keratinocytes with scanning EM. Here bifurcations of individual filaments could unambiguously be identified additionally to bundle branchings. Interestingly, identical filament bifurcations were also found in purified keratin 8/18 filaments expressed in Escherichia coli which were reassembled in vitro. This excludes that an accessory protein contributes to the branch formation. Measurements of the filament cross sectional areas showed various ratios between the three bifurcation arms. This demonstrates that intermediate filament furcation is very different from actin furcation where an entire new filament is attached to an existing filament. Instead, the architecture of intermediate filament bifurcations is less predetermined and hence consistent with the general concept of IF formation.

  1. NCI: DCTD: Biometric Research Branch

    Science.gov (United States)

    The Biometric Research Branch (BRB) is the statistical and biomathematical component of the Division of Cancer Treatment, Diagnosis and Centers (DCTDC). Its members provide statistical leadership for the national and international research programs of the division in developmental therapeutics, developmental diagnostics, diagnostic imaging and clinical trials.

  2. Paired Watershed Study of Suspended Sediment Sources in a Watershed Undergoing Road-Building and Timber Harvest, Railroad Gulch, Coastal Northern California, USA

    Science.gov (United States)

    Stubblefield, A. P.; Beach, S.; Harrison, N.; Haskins, M.; MacDonald, L. H.

    2016-12-01

    This presentation reports on the first three years of a paired watershed study to evaluate sediment sources and sediment delivery from roads and timber harvest units in in two small, highly erodible watersheds on the South Fork of the Elk River in coastal Northern California. The study design includes two years of pre-treatment, one year of data collection after road construction, and four years of monitoring after timber harvest in year four. The control watershed is the 1.48 km2 West Branch of Railroad Gulch. The 1.28 km2 East Branch had 0.84 km of new road construction in summer 2015 and 1.52 km of road reopening. 47% of the watershed was selectively logged in summer 2016 using both ground-based and cable logging. Road condition surveys assess rill erosion and delivery to waterways. Headward migration of low order waterways and landslide activation and delivery is assessed with aerial and field surveys. Further field measurements include streamside landslide and channel bank erosion inventories, cross section surveys, and pebble counts. During storm events turbidity synoptic sampling takes place on the main stem of each branch and at small tributary mouths. Monitoring at the outlets of the basins consists of continuous turbidity and discharge recording throughout the year, and automated pump sampling and synoptic sampling for total suspended sediment concentrations during storm events. Rainfall and peak flow analysis, and determination of long term erosion rates with Be-10 methods, completes the study. The initial results indicate that suspended sediment loads from the two basins are strongly correlated, with respectively 38.26 and 49.22 Mg km-2 from the East and West Branch in the exceptionally dry water year of 2014, and 716.07 and 860.55 Mg km-2 in water year 2015. The much higher loading in 2015 is attributed to the higher rainfall, particularly one large storm that triggered debris torrents and streamside failures. Shallow landslides that are hydrologically

  3. Geology of the Teakettle Creek watersheds

    Science.gov (United States)

    Robert S. LaMotte

    1937-01-01

    The Teakettle Creek Experimental Watersheds lie for the most part on quartzites of probable Triassic age. However one of the triplicate drainages has a considerable acreage developed on weathered granodiorite. Topography is relatively uniform and lends itself to triplicate watershed studies. Locations for dams are suitable if certain engineering precautions...

  4. Watershed: A Successful Voyage into Integrative Learning.

    Science.gov (United States)

    Springer, Mark

    This book describes a "whole learning" approach to education called the Watershed Program, which stresses integrated curriculum and experiential learning. Each chapter begins with an episode from the history of eastern Pennsylvania along the Brandywine River, used as an analogy to problems faced by the teachers in the Watershed program.…

  5. Segmentation by watersheds : definition and parallel implementation

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.; Meijster, Arnold

    1997-01-01

    The watershed algorithm is a method for image segmentation widely used in the area of mathematical morphology. In this paper we first address the problem of how to define watersheds. It is pointed out that various existing definitions are not equivalent. In particular we explain the differences betw

  6. 18 CFR 801.9 - Watershed management.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Watershed management... GENERAL POLICIES § 801.9 Watershed management. (a) The character, extent, and quality of water resources... management including soil and water conservation measures, land restoration and rehabilitation,...

  7. Uncertainty Consideration in Watershed Scale Models

    Science.gov (United States)

    Watershed scale hydrologic and water quality models have been used with increasing frequency to devise alternative pollution control strategies. With recent reenactment of the 1972 Clean Water Act’s TMDL (total maximum daily load) component, some of the watershed scale models are being recommended ...

  8. Retrospect and prospect of watershed hydrological model

    Institute of Scientific and Technical Information of China (English)

    B.CHEN; Z.F.YANG; 等

    2001-01-01

    A brief review is presented of the development of watershed hydrological models,COnventional Hydrological Model,Grey Hydrological Model,Digital Hydrological Model and Intelligent Hydrological Model are analyzed.The Frameworks of Fuzzy Cognitive Hydrological Model and Integrated Digital Watershed Hydrological Model are presented.

  9. Watershed Management: Lessons from Common Property Theory

    Directory of Open Access Journals (Sweden)

    John Kerr

    2007-10-01

    Full Text Available Watershed development is an important component of rural development and natural resource management strategies in many countries. A watershed is a special kind of common pool resource: an area defined by hydrological linkages where optimal management requires coordinated use of natural resources by all users. Management is difficult because natural resources comprising the watershed system have multiple, conflicting uses, so any given management approach will spread benefits and costs unevenly among users. To address these challenges, watershed approaches have evolved from more technocratic to a greater focus on social organization and participation. However, the latter cannot necessarily be widely replicated. In addition, participatory approaches have worked better at a small scale, but hydrological relationships cover a larger scale and some projects have faced tradeoffs in choosing between the two. Optimal approaches for future efforts are not clear, and theories from common property research do not support the idea that complex watershed management can succeed everywhere. Solutions may include simplifying watershed projects, pursuing watershed projects where conditions are favorable, and making other investments elsewhere, including building the organizational capacity that can facilitate watershed management.

  10. Prioritization of sub-watersheds based on morphometric analysis using geospatial technique in Piperiya watershed, India

    Science.gov (United States)

    Chandniha, Surendra Kumar; Kansal, Mitthan Lal

    2017-03-01

    Hydrological investigation and behavior of watershed depend upon geo-morphometric characteristics of catchment. Morphometric analysis is commonly used for development of regional hydrological model of ungauged watershed. A critical valuation and assessment of geo-morphometric constraints has been carried out. Prioritization of watersheds based on water plot capacity of Piperiya watershed has been evaluated by linear, aerial and relief aspects. Morphometric analysis has been attempted for prioritization for nine sub-watersheds of Piperiya watershed in Hasdeo river basin, which is a tributary of the Mahanadi. Sub-watersheds are delineated by ArcMap 9.3 software as per digital elevation model (DEM). Assessment of drainages and their relative parameters such as stream order, stream length, stream frequency, drainage density, texture ratio, form factor, circulatory ratio, elongation ratio, bifurcation ratio and compactness ratio has been calculated separately for each sub-watershed using the Remote Sensing (RS) and Geospatial techniques. Finally, the prioritized score on the basis of morphometric behavior of each sub-watershed is assigned and thereafter consolidated scores have been estimated to identify the most sensitive parameters. The analysis reveals that stream order varies from 1 to 5; however, the first-order stream covers maximum area of about 87.7 %. Total number of stream segment of all order is 1,264 in the watershed. The study emphasizes the prioritization of the sub-watersheds on the basis of morphometric analysis. The final score of entire nine sub-watersheds is assigned as per erosion threat. The sub-watershed with the least compound parameter value was assigned as highest priority. However, the sub-watersheds has been categorized into three classes as high (4.1-4.7), medium (4.8-5.3) and low (>5.4) priority on the basis of their maximum (6.0) and minimum (4.1) prioritized score.

  11. Elk River Watershed - Flood Study

    Science.gov (United States)

    Barnes, C. C.; Byrne, J. M.; MacDonald, R. J.; Lewis, D.

    2014-12-01

    Flooding has the potential to cause significant impacts to economic activities as well as to disrupt or displace populations. Changing climate regimes such as extreme precipitation events increase flood vulnerability and put additional stresses on infrastructure. Potential flooding from just under 100 (2009 NPRI Reviewed Facility Data Release, Environment Canada) toxic tailings ponds located in Canada increase risk to human safety and the environment. One such geotechnical failure spilt billions of litres of toxic tailings into the Fraser River watershed, British Columbia, when a tailings pond dam breach occurred in August 2014. Damaged and washed out roadways cut access to essential services as seen by the extensive floods that occurred in Saskatchewan and Manitoba in July 2014, and in Southern Alberta in 2013. Recovery efforts from events such as these can be lengthy, and have substantial social and economic impacts both in loss of revenue and cost of repair. The objective of this study is to investigate existing conditions in the Elk River watershed and model potential future hydrological changes that can increase flood risk hazards. By analyzing existing hydrology, meteorology, land cover, land use, economic, and settlement patterns a baseline is established for existing conditions in the Elk River watershed. Coupling the Generate Earth Systems Science (GENESYS) high-resolution spatial hydrometeorological model with flood hazard analysis methodology, high-resolution flood vulnerability base line maps are created using historical climate conditions. Further work in 2015 will examine possible impacts for a range of climate change and land use change scenarios to define changes to future flood risk and vulnerability.

  12. Payments for watershed services: opportunities and realities

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Ivan

    2007-08-15

    Many nations have found that regulatory approaches to land and water management have limited impact. An alternative is to create incentives for sound management - under mechanisms known as payments for ecosystem services. It is a simple idea: people who look after ecosystems that benefit others should be recognised and rewarded. In the case of watersheds, downstream beneficiaries of wise upstream land and water use should compensate the stewards. To be effective these 'payments for watershed services' must cover the cost of watershed management. In developing countries, they might also aid local development and reduce poverty. But new research shows that the problems in watersheds are complex and not easily solved. Payments for watershed services do not guarantee poverty reduction and cannot replace the best aspects of regulation.

  13. Measuring environmental sustainability of water in watersheds.

    Science.gov (United States)

    Hester, Erich T; Little, John C

    2013-08-06

    Environmental sustainability assessment is a rapidly growing field where measures of sustainability are used within an assessment framework to evaluate and compare alternative actions. Here we argue for the importance of evaluating environmental sustainability of water at the watershed scale. We review existing frameworks in brief before reviewing watershed-relevant measures in more detail. While existing measures are diverse, overlapping, and interdependent, certain attributes that are important for watersheds are poorly represented, including spatial explicitness and the effect of natural watershed components, such as rivers. Most studies focus on one or a few measures, but a complete assessment will require use of many existing measures, as well as, perhaps, new ones. Increased awareness of the broad dimensions of environmental sustainability as applied to water management should encourage integration of existing approaches into a unified assessment framework appropriate for watersheds.

  14. Finite difference method to find period-one gait cycles of simple passive walkers

    Science.gov (United States)

    Dardel, Morteza; Safartoobi, Masoumeh; Pashaei, Mohammad Hadi; Ghasemi, Mohammad Hassan; Navaei, Mostafa Kazemi

    2015-01-01

    Passive dynamic walking refers to a class of bipedal robots that can walk down an incline with no actuation or control input. These bipeds are sensitive to initial conditions due to their style of walking. According to small basin of attraction of passive limit cycles, it is important to start with an initial condition in the basin of attraction of stable walking (limit cycle). This paper presents a study of the simplest passive walker with point and curved feet. A new approach is proposed to find proper initial conditions for a pair of stable and unstable period-one gait limit cycles. This methodology is based on finite difference method which can solve the nonlinear differential equations of motion on a discrete time. Also, to investigate the physical configurations of the walkers and the environmental influence such as the slope angle, the parameter analysis is applied. Numerical simulations reveal the performance of the presented method in finding two stable and unstable gait patterns.

  15. Changes in zonal surface temperature gradients and Walker circulations in a wide range of climates

    CERN Document Server

    Merlis, Timothy M

    2010-01-01

    Variations in zonal surface temperature gradients and zonally asymmetric tropical overturning circulations (Walker circulations) are examined over a wide range of climates simulated with an idealized atmospheric general circulation model (GCM). The asymmetry in the tropical climate is generated by an imposed ocean energy flux, which does not vary with climate. The range of climates is simulated by modifying the optical thickness of an idealized longwave absorber (representing greenhouse gases). The zonal surface temperature gradient in low latitudes generally decreases as the climate warms in the idealized GCM simulations. A scaling relationship based on a two-term balance in the surface energy budget accounts for the changes in the zonally asymmetric component of the GCM-simulated surface temperature gradients. As in comprehensive simulations of climate change, the Walker circulation weakens as the climate warms in the idealized simulations. The wide range of climates allows a systematic test of energetic ar...

  16. Decoherence induced by a chaotic environment: A quantum walker with a complex coin

    CERN Document Server

    Ermann, L; Saraceno, M; Ermann, Leonardo; Paz, Juan Pablo; Saraceno, Marcos

    2005-01-01

    We study the differences between the process of decoherence induced by chaotic and regular environments. For this we analyze a family of simple models wich contain both regular and chaotic environments. In all cases the system of interest is a "quantum walker", i.e. a quantum particle that can move on a lattice with a finite number of sites. The walker interacts with an environment wich has a D dimensional Hilbert space. The results we obtain suggest that regular and chaotic environments are not distinguishable from each other in a (short) timescale t*, wich scales with the dimensionality of the environment as t*~log(D). Howeber, chaotic environments continue to be effective over exponentially longer timescales while regular environments tend to reach saturation much sooner. We present both numerical and analytical results supporting this conclusion. The family of chaotic evolutions we consider includes the so-called quantum multi-baker-map as a particular case.

  17. Sex differences in moral reasoning: response to Walker's (1984) conclusion that there are none.

    Science.gov (United States)

    Baumrind, D

    1986-04-01

    Data from the Family Socialization and Developmental Competence Project are used to probe Walker's conclusion that there are no sex differences in moral reasoning. Ordinal and nominal nonparametric statistics result in a complex but theoretically meaningful network of relationships among sex, educational level, and Kohlberg stage score level, with the presence and direction of sex differences in stage score level dependent on educational level. The effects on stage score level of educational level and working status are also shown to differ for men and women. Reasons are considered for not accepting Walker's dismissal of studies that use (a) a pre-1983 scoring manual, or (b) fail to control for education. The problems presented to Kohlberg's theory by the significant relationship between educational and stage score levels in the general population are discussed, particularly as these apply to the postconventional level of moral reasoning.

  18. Meckel-Gruber syndrome concomitant with Dandy-Walker malformation: prenatal sonographic diagnosis in two cases.

    Science.gov (United States)

    Yapar, E G; Ekici, E; Dogan, M; Gökmen, O

    1996-10-01

    Meckel-Gruber syndrome is an autosomal recessive disorder which comprises a characteristic triad of major abnormalities: renal cystic dysplasia, occipital encephalocele, and postaxial polydactyly. Because of the recessive inheritance, prenatal sonographic diagnosis is paramount for informed genetic counselling of affected pregnancies. However, Meckel-Gruber syndrome may demonstrate variation in phenotypic expression when some malformations are different from those traditionally accepted and cases may be evaluated as a different syndrome. The aim of this paper is to emphasise the phenotypic variability in Meckel-Gruber syndrome, and the importance of the prenatal sonography in the diagnosis. We also suggest that Dandy-Walker malformation or Dandy-Walker variant be accepted as one of the malformations which occur in the central nervous system as a part of the syndrome.

  19. Relativistic Chaos in Robertson-Walker Cosmologies The Topological Structure of Space-Time and the Microscopic Dynamics

    CERN Document Server

    Tomaschitz, R

    1991-01-01

    Keywords: Robertson-Walker cosmology, relativistic chaos, mixing, Bernoulli property, time evolution, quantum fields, quantum chaos, bound states, energy functional, hyperbolic manifold, deformation space, Kleinian group, limit set, Hausdorff dimension, convex hull.

  20. Maternal grand mal seizure leads to a surprising diagnosis of Dandy-Walker variant.

    Science.gov (United States)

    Mendelson, Sherri G

    2011-01-01

    Pregnant women may present with abnormal symptoms that are assumed to be related to the pregnancy. The purpose of this case study is to examine an obstetric case that provides a wider view of a grand mal seizure in a perinatal patient with previously undiagnosed Dandy-Walker Variant. When a pregnant or newly postpartum woman has seizures, eclampsia may be the most the most likely diagnosis, but it may not be accurate.

  1. Inhomogeneous relativistic Boltzmann equation near vacuum in the Robertson-Walker space-time

    CERN Document Server

    Takou, Etienne

    2016-01-01

    In this paper, we consider the Cauchy problem for the relativistic Boltzmann equation with near vacuum initial data where the distribution function depends on the time, the position and the impulsion. The collision kernel considered here is for the hard potentials case and the background space-time in which the study is done is the Robertson-Walker space-time. Unique global (in time) mild solution is obtained in a suitable weighted space.

  2. On uniqueness of the foliation by comoving observers restspaces of a Generalized Robertson-Walker spacetime

    Science.gov (United States)

    Pelegrín, José A. S.; Romero, Alfonso; Rubio, Rafael M.

    2017-02-01

    A characterization of the foliation by spacelike slices of an (n+1)-dimensional spatially closed Generalized Robertson-Walker spacetime is given by means of studying a natural mean curvature type equation on spacelike graphs. Under some natural assumptions, of physical or geometric nature, all the entire solutions of such an equation are obtained. In particular, the case of entire spacelike graphs in de Sitter spacetime is faced and completely solved by means of a new application of a known integral formula.

  3. On the number of common sites visited by N random walkers

    CERN Document Server

    Turban, L

    2016-01-01

    Majumdar and Tamm [Phys. Rev. E 86 021135 (2012), arXiv:1206.6184] recently obtained analytical expressions for the mean number of common sites W_N(t) visited up to time t by N independent random walkers starting from the origin of a d-dimensional lattice. In this short note I show how the different regimes and the corresponding asymptotic power laws can be retrieved using the notion of fractal intersection.

  4. Quantum evolution of scalar fields in Robertson-Walker space-time

    CERN Document Server

    Éboli, Oscar J P

    1995-01-01

    We study the \\lambda \\phi^4 field theory in a flat Robertson-Walker space-time using the functional Sch\\"odinger picture. We introduce a simple Gaussian approximation to analyze the time evolution of pure states and we establish the renormalizability of the approximation. We also show that the energy-momentum tensor in this approximation is finite once we consider the usual mass and coupling constant renormalizations.

  5. Johnnie Walker Classic 2007泰国普吉岛三月精彩呈献

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ 畅销全球的苏格兰威士忌品牌Johnnie Walker呈献给亚太地区的顶极高尔夫赛事--第16届Johnnie Walker Classic高尔夫球赛将于2007年3月1日至4日在泰国普吉岛Blue Canyon乡村高尔夫俱乐部举行.

  6. Women in History--Madame C. J. Walker 1867-1919

    Science.gov (United States)

    Huber, Germaine W.

    2009-01-01

    This article profiles Madame C. J. Walker. Sarah Breedlove was born on December 23, 1867, the fifth of six children of Owen and Minerva Breedlove. Sarah was the first of the Breedlove children to be born after the end of slavery. Her parents died when she was six or seven years of age. At age fourteen she married Moses McWilliams, who also died in…

  7. Neurocutaneous Melanosis in Association with Dandy-Walker Complex with Extensive Intracerebral and Spinal Cord Involvement

    OpenAIRE

    Sung, Kyoung-Su; Song, Young-Jin

    2014-01-01

    Neurocutaneous melanosis (NCM) is a rare congenital syndrome consisting of benign or malignant melanotic tumors of the central nervous system with large or numerous cutaneous melanocytic nevi. The Dandy-Walker complex (DWC) is characterized by an enlarged posterior fossa with high insertion of the tentorium, hypoplasia or aplasia of the cerebellar vermis, and cystic dilatation of the fourth ventricle. These each two conditions are rare, but NCM associated with DWC is even more rare. Most pati...

  8. Argentinean species of Chalarus Walker (Diptera: Pipunculidae): new records and description of Chalarus tani n. sp.

    Science.gov (United States)

    Rodríguez, H C; Rafael, J A; Virla, E G

    2012-04-01

    The Argentinean species of Chalarus Walker were studied. Pipunculidae adults belonging to four species, C halarus chilensis Collin, Chalarus triramosus Rafael, Chalarus absonus Rafael and Chalarus tani n. sp. were described based on two male specimens collected in the La Rioja and Tucuman Provinces, northwestern region of Argentina. Chalarus absonus is recorded for the first time in Argentina. New distributional data and an identification key to the adult males of the Argentinean representatives are provided including figures.

  9. 41-D crewmembers Resnik and Walker prepare experiments in training for flight

    Science.gov (United States)

    1984-01-01

    Astronaut Judith A. Resnik, mission specialist, and Charles D. Walker, payload specialist for 41-D, prepare for some scheduled intravehicular activity involving the continuous flow electrophoresis systems (CFES) experiment. In the background are stowage lockers and a CFES trainer - part of the shuttle one-G trainer at JSC (35755,35757); Resnik works with a sample connected to the CFE experiment during training session (35756,35758).

  10. Hadronic Matter in the Robertson-Walker Metric and the Early Universe

    CERN Document Server

    Cunha, Ivan E

    2015-01-01

    In this work, the Friedman equations for hadronic matter in the Robertson-Walker metric in the early Universe are obtained. We consider the hadronic phase, formed after the hadronization of the quark-gluon plasma, that means times from 10^{-6}s to 1s. The set of equations is derived and the behavior of the system is studied considering one approximate analytical solution.

  11. Paciente com variante da síndrome de Dandy Walker

    Directory of Open Access Journals (Sweden)

    Robson Luis Ribeiro Andrade Filho

    2015-10-01

    Full Text Available O quadro que seria conhecido atualmente como Síndrome de Dandy Walker, foi caracterizada por um conjunto de sinais derivados de alterações na embriogênese, principalmente no que tange a gênese do sistema nervoso central. A patogenia é classificada majoritariamente em três formas, sendo a mais comum a variante de Dandy Walker. Tem-se por objetivo, o relato do caso de um paciente masculino, 3 meses de idade, portador da Variante da Síndrome de Dandy Walker. O paciente apresentava ao exame físico geral e específico dos sistemas: macrocefalia, hidrocele, apêndices em mãos e pés, microgenitália, hérnia inguinal. Em relação ao acometimento cardíaco, havia dilatação ventricular esquerda, bulhas hipofonéticas e sopros holossistólicos. Na ressonância magnética foi observada ausência de vermis cerebelar e aumento anormal do quarto ventrículo. Método: as informações foram obtidas mediante revisão de prontuário, exames de imagem e levantamento para estudo de literatura específica referente ao caso. Considerações finais e relevância: o caso relatado e o estudo das referências apontam a caracterização do paciente na variante de Dandy Walker, tendo em consideração seu fenótipo variável. Malformações devem ser pesquisadas intra e extracranianas através de pesquisa clínica e radiológica, de forma a minimizar as taxas de mortalidade em recém-nascidos portadores da síndrome.

  12. On Parallel Transport in Quantum Bundles over Robertson-Walker Spacetimes

    OpenAIRE

    1996-01-01

    A recently-developed theory of quantum general relativity provides a propagator for free-falling particles in curved spacetimes. These propagators are constructed by parallel-transporting quantum states within a quantum bundle associated to the Poincare frame bundle. We consider such parallel transport in the case that the spacetime is a classical Robertson-Walker universe. An explicit integral formula is developed which expresses the propagators for parallel transport between any two points ...

  13. Test pilots 1962 - Thompson, McKay, Dana, Armstrong, Peterson, Butchart, Walker

    Science.gov (United States)

    1962-01-01

    A group photo of NASA research pilots at the front door of the Flight Research Center headquarters building. In the front row are (left to right) Milt Thompson, Jack McKay, and Bill Dana. All three flew the X-15, and Thompson and Dana were also involved in the lifting body flights. McKay was injured in a crash landing in X-15 #2. Although he recovered, the injuries eventually forced him to retire from research flying. In the back row (left to right) are Neil Armstrong, Bruce Peterson, Stanley Butchart, and Joe Walker. Armstrong and Walker also both flew the X-15. Soon after this photo was taken, Armstrong was selected as an astronaut, and seven years later became the first man to walk on the Moon. Walker made the highest flight in the X-15, reaching 354,200 feet. He then went on to fly the Lunar Landing Research Vehicle, and was killed on June 8, 1966 when his F-104N collided with the XB-70. Peterson made the first flight in the HL-10 lifting body, and was later badly injured in the crash of the M2-F2 lifting body. Butchart flew a wide range of research missions in the 1950s, and was the B-29 drop plane pilot for a number of rocket flight.

  14. Covariant and quasi-covariant quantum dynamics in Robertson-Walker space-times

    CERN Document Server

    Buchholz, D; Summers, S J; Buchholz, Detlev; Mund, Jens; Summers, Stephen J.

    2002-01-01

    We propose a canonical description of the dynamics of quantum systems on a class of Robertson-Walker space-times. We show that the worldline of an observer in such space-times determines a unique orbit in the local conformal group SO(4,1) of the space-time and that this orbit determines a unique transport on the space-time. For a quantum system on the space-time modeled by a net of local algebras, the associated dynamics is expressed via a suitable family of ``propagators''. In the best of situations, this dynamics is covariant, but more typically the dynamics will be ``quasi-covariant'' in a sense we make precise. We then show by using our technique of ``transplanting'' states and nets of local algebras from de Sitter space to Robertson-Walker space that there exist quantum systems on Robertson-Walker spaces with quasi-covariant dynamics. The transplanted state is locally passive, in an appropriate sense, with respect to this dynamics.

  15. Do Canes or Walkers Make Any Difference? NonUse and Fall Injuries.

    Science.gov (United States)

    Luz, Clare; Bush, Tamara; Shen, Xiaoxi

    2017-04-01

    Examine patterns of cane and walker use as related to falls and fall injuries. Among people who fall at home, most do not have an assistive device with them when they fall. Nonusers who fall sustain more severe injuries. This was a cross-sectional study using a self-administered written survey completed by 262 people aged 60 and older who were community dwelling, cognitively intact, and current cane/walker users with a history of falls. They were recruited through clinical practice sites, churches, and senior housing in central Michigan. Outcomes of interest included patterns of device use, reasons for nonuse, device use at time of fall, and fall-related injuries. Seventy-five percent of respondents who fell were not using their device at the time of fall despite stating that canes help prevent falls. Reasons for nonuse included believing it was not needed, forgetfulness, the device made them feel old, and inaccessibility. Perceived risk was not high enough to engage in self-protective behavior. However, nonuse led to a significantly higher proportion of falls resulting in surgery than among device users. Among respondents requiring surgery, 100% were nonusers. Most respondents never received a home safety evaluation (68%) and only 50% received training on proper device use. Providers must place increased emphasis on the importance of cane/walker use for injury prevention through patient education to promote personal relevance, proper fitting, and training. New strategies are needed to improve device acceptability and accessibility.

  16. Robust spinal neuroinflammation mediates mechanical allodynia in Walker 256 induced bone cancer rats.

    Science.gov (United States)

    Mao-Ying, Qi-Liang; Wang, Xiao-Wei; Yang, Chang-Jiang; Li, Xiu; Mi, Wen-Li; Wu, Gen-Cheng; Wang, Yan-Qing

    2012-05-20

    It has been reported that remarkable and sustained activation of astrocytes and/or microglia occurs in cancer induced pain (CIP), which is different from neuropathic and inflammatory pain. The present study was designed to investigate the role of spinal Toll-like receptor 4 (TLR4) induced glial neuroinflammation in cancer induced pain using a modified rat model of bone cancer. The rat model of CIP consisted of unilateral intra-tibial injection with Walker 256 mammary gland carcinoma. Nine days after Walker 256 inoculation, a robust activation of both astrocytes and microglia in bilateral spinal dorsal horn was observed together with significant bilateral mechanical allodynia. This neuroinflammation was characterized by enhanced immunostaining of both glial fibrillary acidic protein (GFAP, astrocyte marker) and OX-42 (microglia marker), and an elevated level of IL-1β, IL-6 and TNF-α mRNA. I.t. administration of fluorocitrate (an inhibitor of glial metabolism, 1 nmol) or minocycline (an inhibitor of microglia, 100 μg) has significant anti-allodynic effects on day 12 after Walker 256 inoculation. Naloxone (a nonstereoselective TLR4 signaling blocker, 60 μg, i.t.) also significantly alleviated mechanical allodynia and simultaneously blocked the increased inflammatory cytokine mRNA. The results suggested that spinal TLR4 might play an important role in the sustained glial activation that critically contributed to the robust and sustained spinal neuroinflammation in CIP. This result could potentially help clinicians and researchers to better understand the mechanism of complicated cancer pain.

  17. Detection of Gait Perturbations Based on Proprioceptive Information. Application to Limit Cycle Walkers

    Directory of Open Access Journals (Sweden)

    J. A. Gallego

    2012-01-01

    Full Text Available Walking on irregular surfaces and in the presence of unexpected events is a challenging problem for bipedal machines. Up to date, their ability to cope with gait disturbances is far less successful than humans’: Neither trajectory controlled robots, nor dynamic walking machines (Limit Cycle Walkers are able to handle them satisfactorily. On the contrary, humans reject gait perturbations naturally and efficiently relying on their sensory organs that, if needed, elicit a recovery action. A similar approach may be envisioned for bipedal robots and exoskeletons: An algorithm continuously observes the state of the walker and, if an unexpected event happens, triggers an adequate reaction. This paper presents a monitoring algorithm that provides immediate detection of any type of perturbation based solely on a phase representation of the normal walking of the robot. The proposed method was evaluated in a Limit Cycle Walker prototype that suffered push and trip perturbations at different moments of the gait cycle, providing 100% successful detections for the current experimental apparatus and adequately tuned parameters, with no false positives when the robot is walking unperturbed.

  18. Compaction properties of crystalline pharmaceutical ingredients according to the Walker model and nanomechanical attributes.

    Science.gov (United States)

    Egart, M; Ilić, I; Janković, B; Lah, N; Srčič, S

    2014-09-10

    This study investigates the extent to which single-crystal mechanical properties of selected active ingredients (famotidine, nifedipine, olanzapine, piroxicam) influence their bulk compressibility and compactibility. Nanomechanical attributes of oriented single crystals were determined with instrumented nanoindentation, and bulk deformational properties were assessed with the Walker and Heckel models as well as the elastic relaxation index. Good correlations were established between bulk and single-crystal plasticity parameters: the Walker coefficient and indentation hardness. The Walker model showed more practical value for evaluating bulk deformational properties of the APIs investigated because their properties differed more distinctly compared to the Heckel model. In addition, it was possible to predict the elastic properties of the materials investigated at the bulk level because a correlation between the elastic relaxation index and compliance was established. The value of using indentation hardness for crystalline APIs was also confirmed because their compactibility at the bulk level was able to be predicted. Mechanically interlocked structures were characteristic of most polymorphic forms investigated, resulting in single crystals having isotropic mechanical properties. It was revealed that in such cases good correlations between single and bulk mechanical properties can be expected. The results imply that innate crystal deformational properties define their compressibility and compactibility properties to a great extent. Copyright © 2014. Published by Elsevier B.V.

  19. The importance of being marginal: Norma Ford Walker and a Canadian school of medical genetics.

    Science.gov (United States)

    Miller, Fiona

    2002-08-30

    This study reviews the development of a medical genetics research tradition in Toronto, Canada. This research tradition, what I call the "Ford Walker school," was forged in the 1930s in an iconoclastic mold. It was female-dominated in an era when leading-edge science was definitely not "women's work." It emerged in a leading research university, but in a country that lagged in the sciences. These social relations of gender and nation symbolized and sustained a marginality that was reinforced by the substantive concerns of members of this research school. They adopted a service orientation toward medicine, were sympathetic to heterodox approaches to genetic and medical science, and were principally reliant on a marginal research tool-dermatoglyphics. Despite this marginality, Norma Ford Walker was among the founding members of the institutions of human and medical genetics in North America in the postwar period. She forged a research tradition that served as the basis for further developments in medical genetics in Toronto and educated a generation of students, many of them women, who went on to populate and then institutionalize the growing science and practice of medical genetics in Canada. The heterodox approach of the early Ford Walker school was displaced as the field grew in the postwar period. Yet many members of the research school retained dermatoglyphic technique and used it to contribute to progress in medical cytogenetics. In this article, I explore why the history of this marginal research school is important.

  20. Streamers in air splitting into three branches

    CERN Document Server

    Heijmans, L C J; van Veldhuizen, E M; Ebert, U

    2013-01-01

    We investigate the branching of positive streamers in air and present the first systematic investigation of splitting into more than two branches. We study discharges in 100 mbar artificial air that is exposed to voltage pulses of 10 kV applied to a needle electrode 160 mm above a grounded plate. By imaging the discharge with two cameras from three angles, we establish that about every 200th branching event is a branching into three. Branching into three occurs more frequently for the relatively thicker streamers. In fact, we find that the surface of the total streamer cross-sections before and after a branching event is roughly the same.

  1. Model Calibration in Watershed Hydrology

    Science.gov (United States)

    Yilmaz, Koray K.; Vrugt, Jasper A.; Gupta, Hoshin V.; Sorooshian, Soroosh

    2009-01-01

    Hydrologic models use relatively simple mathematical equations to conceptualize and aggregate the complex, spatially distributed, and highly interrelated water, energy, and vegetation processes in a watershed. A consequence of process aggregation is that the model parameters often do not represent directly measurable entities and must, therefore, be estimated using measurements of the system inputs and outputs. During this process, known as model calibration, the parameters are adjusted so that the behavior of the model approximates, as closely and consistently as possible, the observed response of the hydrologic system over some historical period of time. This Chapter reviews the current state-of-the-art of model calibration in watershed hydrology with special emphasis on our own contributions in the last few decades. We discuss the historical background that has led to current perspectives, and review different approaches for manual and automatic single- and multi-objective parameter estimation. In particular, we highlight the recent developments in the calibration of distributed hydrologic models using parameter dimensionality reduction sampling, parameter regularization and parallel computing.

  2. Mercury cycling in terrestrial watersheds

    Science.gov (United States)

    Shanley, James B.; Bishop, Kevin; Banks, Michael S.

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  3. Different seasonality of nitrate export from an agricultural watershed and an urbanized watershed in Midwestern USA

    Science.gov (United States)

    Tian, S.; Youssef, M. A.; Richards, R. P.; Liu, J.; Baker, D. B.; Liu, Y.

    2016-10-01

    Land use/land cover is a critical factor affecting temporal dynamics of nitrate export from watersheds. Based on a long-term (>30 years) water quality monitoring program in the Western Lake Erie area, United States, this study compared seasonal variation of nitrate export from an agricultural watershed and an urbanized watershed. A seasonality index was adapted to quantitatively characterize seasonal variation of nitrate export from the two watersheds. Results showed that monthly nitrate concentrations from the two watersheds exhibited different seasonal variation. Seasonality index of monthly nitrate loading for the agricultural watershed is approximately 3 times of that from the urbanized watershed and the difference is statistically significant (p export from the two watersheds were mainly attributed to their distinct nitrogen sources, physical and biogeochemical settings. The declining seasonality index of monthly nitrate loading from the agricultural watershed could be partially caused by historical climate change in the study region, especially increased temperature during winter. Urbanization could be one key factor contributing to the declining seasonality index of monthly nitrate loading from the urbanized watershed. Information derived from this study have practical implications for developing proper management practices to mitigate nitrate pollution in Midwestern United States.

  4. A Novel Function for the Conserved Glutamate Residue in the Walker B Motif of Replication Factor C

    Directory of Open Access Journals (Sweden)

    Linda B. Bloom

    2013-03-01

    Full Text Available In all domains of life, sliding clamps tether DNA polymerases to DNA to increase the processivity of synthesis. Clamp loaders load clamps onto DNA in a multi-step process that requires ATP binding and hydrolysis. Like other AAA+ proteins, clamp loaders contain conserved Walker A and Walker B sequence motifs, which participate in ATP binding and hydrolysis, respectively. Mutation of the glutamate residue in Walker B motifs (or DExx-boxes in AAA+ proteins typically reduces ATP hydrolysis by as much as a couple orders of magnitude, but has no effect on ATP binding. Here, the Walker B Glu in each of the four active ATP sites of the eukaryotic clamp loader, RFC, was mutated to Gln and Ala separately, and ATP binding- and hydrolysis-dependent activities of the quadruple mutant clamp loaders were characterized. Fluorescence-based assays were used to measure individual reaction steps required for clamp loading including clamp binding, clamp opening, DNA binding and ATP hydrolysis. Our results show that the Walker B mutations affect ATP-binding-dependent interactions of RFC with the clamp and DNA in addition to reducing ligand-dependent ATP hydrolysis activity. Here, we show that the Walker B glutamate is required for ATP-dependent ligand binding activity, a previously unknown function for this conserved Glu residue in RFC.

  5. BDC 500 branch driver controller

    CERN Document Server

    Dijksman, A

    1981-01-01

    This processor has been designed for very fast data acquisition and date pre-processing. The dataway and branch highway speeds have been optimized for approximately 1.5 mu sec. The internal processor cycle is approximately 0.8 mu sec. The standard version contains the following functions (slots): crate controller type A1; branch highway driver including terminator; serial I/O port (TTY, VDU); 24 bit ALU and 24 bit program counter; 16 bit memory address counter and 4 word stack; 4k bit memory for program and/or data; battery backup for the memory; CNAFD and crate LAM display; request/grant logic for time- sharing operation of several BDCs. The free slots can be equipped with e.g. extra RAM, computer interfaces, hardware multiplier/dividers, etc. (0 refs).

  6. MAPPING WATERSHED INTEGRITY FOR THE CONTERMINOUS UNITED STATES.

    Science.gov (United States)

    Watersheds provide a variety of ecosystem services valued by society. Production of these services is sensitive to watershed alteration by human activities. Flotemersch and others (2015), defined watershed integrity (WI) as the “capacity of a watershed to support and maint...

  7. Solid State Photovoltaic Research Branch

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  8. Branching processes and neutral evolution

    CERN Document Server

    Taïb, Ziad

    1992-01-01

    The Galton-Watson branching process has its roots in the problem of extinction of family names which was given a precise formulation by F. Galton as problem 4001 in the Educational Times (17, 1873). In 1875, an attempt to solve this problem was made by H. W. Watson but as it turned out, his conclusion was incorrect. Half a century later, R. A. Fisher made use of the Galton-Watson process to determine the extinction probability of the progeny of a mutant gene. However, it was J. B. S. Haldane who finally gave the first sketch of the correct conclusion. J. B. S. Haldane also predicted that mathematical genetics might some day develop into a "respectable branch of applied mathematics" (quoted in M. Kimura & T. Ohta, Theoretical Aspects of Population Genetics. Princeton, 1971). Since the time of Fisher and Haldane, the two fields of branching processes and mathematical genetics have attained a high degree of sophistication but in different directions. This monograph is a first attempt to apply the current sta...

  9. Upper-Ocean Heat Balance Processes and the Walker Circulation in CMIP5 Model Projections

    Science.gov (United States)

    Robertson, F. R.; Roberts, J. B.; Funk, C.; Lyon, B.; Ricciardulli, L.

    2012-01-01

    Considerable uncertainty remains as to the importance of mechanisms governing decadal and longer variability of the Walker Circulation, its connection to the tropical climate system, and prospects for tropical climate change in the face of anthropogenic forcing. Most contemporary climate models suggest that in response to elevated CO2 and a warmer but more stratified atmosphere, the required upward mass flux in tropical convection will diminish along with the Walker component of the tropical mean circulation as well. Alternatively, there is also evidence to suggest that the shoaling and increased vertical stratification of the thermocline in the eastern Pacific will enable a muted SST increase there-- preserving or even enhancing some of the dynamical forcing for the Walker cell flow. Over the past decade there have been observational indications of an acceleration in near-surface easterlies, a strengthened Pacific zonal SST gradient, and globally-teleconnected dislocations in precipitation. But is this evidence in support of an ocean dynamical thermostat process posited to accompany anthropogenic forcing, or just residual decadal fluctuations associated with variations in warm and cold ENSO events and other stochastic forcing? From a modeling perspective we try to make headway on this question by examining zonal variations in surface energy fluxes and dynamics governing tropical upper ocean heat content evolution in the WCRP CMIP5 model projections. There is some diversity among model simulations; for example, the CCSM4 indicates net ocean warming over the IndoPacific region while the CSIRO model concentrates separate warming responses over the central Pacific and Indian Ocean regions. The models, as with observations, demonstrate strong local coupling between variations in column water vapor, downward surface longwave radiation and SST; but the spatial patterns of changes in the sign of this relationship differ among models and, for models as a whole, with

  10. Mechanical properties of branched actin filaments

    CERN Document Server

    Razbin, Mohammadhosein; Benetatos, Panayotis; Zippelius, Annette

    2015-01-01

    Cells moving on a two dimensional substrate generate motion by polymerizing actin filament networks inside a flat membrane protrusion. New filaments are generated by branching off existing ones, giving rise to branched network structures. We investigate the force-extension relation of branched filaments, grafted on an elastic structure at one end and pushing with the free ends against the leading edge cell membrane. Single filaments are modeled as worm-like chains, whose thermal bending fluctuations are restricted by the leading edge cell membrane, resulting in an effective force. Branching can increase the stiffness considerably; however the effect depends on branch point position and filament orientation, being most pronounced for intermediate tilt angles and intermediate branch point positions. We describe filament networks without cross-linkers to focus on the effect of branching. We use randomly positioned branch points, as generated in the process of treadmilling, and orientation distributions as measur...

  11. Effect of uphill and downhill walking on walking performance in geriatric patients using a wheeled walker.

    Science.gov (United States)

    Lindemann, Ulrich; Schwenk, Michael; Schmitt, Syn; Weyrich, Michael; Schlicht, Wolfgang; Becker, Clemens

    2017-08-01

    Wheeled walkers are recommended to improve walking performance in older persons and to encourage and assist participation in daily life. Nevertheless, using a wheeled walker can cause serious problems in the natural environment. This study aimed to compare uphill and downhill walking with walking level in geriatric patients using a wheeled walker. Furthermore, we investigated the effect of using a wheeled walker with respect to dual tasking when walking level. A total of 20 geriatric patients (median age 84.5 years) walked 10 m at their habitual pace along a level surface, uphill and downhill, with and without a standard wheeled walker. Gait speed, stride length and cadence were assessed by wearable sensors and the walk ratio was calculated. When using a wheeled walker while walking level the walk ratio improved (0.58 m/[steps/min] versus 0.57 m/[steps/min], p = 0.023) but gait speed decreased (1.07 m/s versus 1.12 m/s, p = 0.020) when compared to not using a wheeled walker. With respect to the walk ratio, uphill and downhill walking with a wheeled walker decreased walking performance when compared to level walking (0.54 m/[steps/min] versus 0.58 m/[steps/min], p = 0.023 and 0.55 m/[steps/min] versus 0.58 m/[steps/min], p = 0.001, respectively). At the same time, gait speed decreased (0.079 m/s versus 1.07 m/s, p < 0.0001) or was unaffected. The use of a wheeled walker improved the quality of level walking but the performance of uphill and downhill walking was worse compared to walking level when using a wheeled walker.

  12. Comparison of mineral weathering and biomass nutrient uptake in two small forested watersheds underlain by quartzite bedrock, Catoctin Mountain, Maryland, USA

    Science.gov (United States)

    Rice, Karen; Price, Jason R.

    2014-01-01

    To quantify chemical weathering and biological uptake, mass-balance calculations were performed on two small forested watersheds located in the Blue Ridge Physiographic Province in north-central Maryland, USA. Both watersheds, Bear Branch (BB) and Fishing Creek Tributary (FCT), are underlain by relatively unreactive quartzite bedrock. Such unreactive bedrock and associated low chemical-weathering rates offer the opportunity to quantify biological processes operating within the watershed. Hydrologic and stream-water chemistry data were collected from the two watersheds for the 9-year period from June 1, 1990 to May 31, 1999. Of the two watersheds, FCT exhibited both higher chemical-weathering rates and biomass nutrient uptake rates, suggesting that forest biomass aggradation was limited by the rate of chemical weathering of the bedrock. Although the chemical-weathering rate in the FCT watershed was low relative to the global average, it masked the influence of biomass base-cation uptake on stream-water chemistry. Any differences in bedrock mineralogy between the two watersheds did not exert a significant influence on the overall weathering stoichiometry. The difference in chemical-weathering rates between the two watersheds is best explained by a larger proportion of reactive phyllitic layers within the bedrock of the FCT watershed. Although the stream gradient of BB is about two-times greater than that of FCT, its influence on chemical weathering appears to be negligible. The findings of this study support the biomass nutrient uptake stoichiometry of K1.0Mg1.1Ca0.97 previously determined for the study site. Investigations of the chemical weathering of relatively unreactive quartzite bedrock may provide insight into critical zone processes.

  13. Modelo experimental de tumor na cavidade oral de ratos com carcinossarcoma de Walker 256 Experimental model of Walker 256 carcinosarcoma developed in the oral cavity of rats

    Directory of Open Access Journals (Sweden)

    Ana Paula Negreiros Nunes Alves

    2004-08-01

    Full Text Available OBJETIVO: Estabelecer um modelo experimental de desenvolvimento tumoral na cavidade oral de ratos, permitindo, assim, o estudo da osteólise induzida pelo tumor nos ossos do complexo maxilomandibular como também nas estruturas dentais, através da caracterização histomorfológica da reabsorção óssea e dentária. MÉTODOS: Uma suspensão de células tumorais (0,1mL do Carcinossarcoma de Walker 256, na concentração de 10(6 células/mL foi implantado na cavidade alveolar de ratos previamente aberta por exodontia. Os animais foram observados durante 12 (doze dias consecutivos para determinação da curva de peso corpóreo, sendo posteriormente sacrificados e as mandíbulas removidas para exames radiográfico e histológico. RESULTADOS: No exame radiográfico foi verificada área lítica, sem evidência de reparo, na região dos alvéolos. No exame microscópico foi identificada infiltração óssea, periférica e central, de pequenas células hipercromáticas e pleomórficas, com leve infiltrado inflamatório mononuclear associado e áreas de necrose. O índice de pega foi de 100%. CONCLUSÃO: O modelo animal de invasão óssea, do tumor de Walker na cavidade oral, possibilita a avaliação in vivo de drogas antitumorais e esquemas terapêuticos no tratamento do câncer bucal.PURPOSE: To estabilish an experimental model of tumor development in the oral cavity of rats, that would enable to study the tumor-induced autolysis in the maxillomandibular bone complex as well as of the dental structures, through histomorphological characterization of bone and dental resorption. METHODS: Walker 256 carcinossarcoma cell suspension (0,1 mL containing 10(6 cell/mL was implanted in the alveoli of first and second molars. The animals were observed during twelve consecutive days and the body weigth were determined. Later, the animals were sacrificed and their mandibles removed to radiographic and hystologic analysis. RESULTS: The radiographic image

  14. 地塞米松对大鼠 Walker 256乳腺癌骨转移癌痛的作用%Effect of dexamethasone on rat bone metastasis pain induced by Walker 256 mammary gland carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    张凡; 李毅; 丁杰; 张海林

    2015-01-01

    Objective To establish a rat model of bone metastasis pain induced by Walker 256 mammary gland carcinoma cells and observe the effect of dexamethasone on bone cancer pain. Methods Ascitic tumour cells were made from Walker 256 mammary gland carcinoma cells injected to tibia of rats.Then,the withdrawal threshold to mechanical stimulus and withdrawal time in response to radiant thermal stimulus were tested before and after operation.Results The withdrawal threshold to mechanical stimulus and withdrawal time in response to radiant thermal stimulus were significantly reduced in the tibia bone inoculated with Walker 256 cells.The pathology results showed the evidence of tibia bone structure was destructed by tumor.It is suggested that the model of bone metastasis pain induced by Walker 256 mammary gland carcinoma cell was successfully established.Dexamethasone (5 mg/kg ) elevated withdrawal threshold to mechanical stimulus in rat model of bone metastasis pain induced by Walker 256 mammary gland carcinoma cell.Conclusion Dexamethasone could alleviate bone cancer pain.%目的:建立大鼠 Walker 256乳腺癌骨转移癌痛模型,观察地塞米松对骨转移癌疼痛痛阈的影响。方法制备 Walker 256乳腺癌细胞的大鼠腹腔积液瘤细胞,将其注射入大鼠胫骨,测量术前及术后机械刺痛阈和辐射热痛阈。结果接种 Walker 256乳腺癌大鼠术侧机械刺激痛觉和辐射热痛觉阈值显著降低,且病理学结果显示骨质受到肿瘤破坏,提示 Walker 256大鼠乳腺癌骨转移癌疼痛模型成功建立。地塞米松(5 mg/kg)能够显著提高骨转移癌疼痛模型刺痛痛阈。结论地塞米松能够缓解大鼠骨转移癌疼痛。

  15. Southern Watersheds Common Reedgrass Monitoring Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Southern Watersheds Common Reedgrass Project is an interagency effort to increase public awareness of the common reedgrass problem, demonstrate effective control...

  16. Southern Watersheds Common Reedgrass Project Progress Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Southern Watersheds includes the drainages of the Northwest River, the North Landing River, and Back Bay in the southeastern corner of Virginia. Common reedgrass...

  17. Tribal boundaries in the Nass watershed

    National Research Council Canada - National Science Library

    Sterritt, N. J; Marsden, S; Galois, R; Grant, P.R; Overstall, R

    1998-01-01

    Tribal Boundaries in the Nass Watershed makes an important contribution to our understanding on how First Nations traditionally establish their rights to territory and to how these rights are played...

  18. Watershed Boundaries, Published in unknown, SWGRC.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Watershed Boundaries dataset, was produced all or in part from Road Centerline Files information as of unknown. Data by this publisher are often provided in...

  19. Watershed impervious cover relative to stream location

    Data.gov (United States)

    U.S. Environmental Protection Agency — Estimates of watershed (12-digit huc) impervious cover and impervious cover near streams and water body shorelines for three dates (2001, 2006, 2011) using NLCD...

  20. Blob Objects Analysis Using Watershed Transformation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper presents a novel method for overlapping or touching blob object ( particles ) segmentation. It is based on the watershed transformation, one of the most powerful image analysis tools provided by mathematical morphology. In this method, we first build the distance function of the blob image, and then extract the regional minima as markers, and finally the watershed transformation is performed. The applications of this algorithm illustrated using the examples of red blood cell segmentation and broken medicine pill detection.

  1. Using Four Capitals to Assess Watershed Sustainability

    Science.gov (United States)

    Pérez-Maqueo, Octavio; Martinez, M. Luisa; Vázquez, Gabriela; Equihua, Miguel

    2013-03-01

    The La Antigua watershed drains into the Gulf of Mexico and can be considered as one of the most important areas in Mexico because of its high productivity, history, and biodiversity, although poverty remains high in the area in spite of these positive attributes. In this study, we performed an integrated assessment of the watershed to recommend a better direction toward a sustainable management in which the four capitals (natural, human, social, and built) are balanced. We contrasted these four capitals in the municipalities of the upper, middle and lower watershed and found that natural capital (natural ecosystems and ecosystem services) was higher in the upper and middle watershed, while human and social capitals (literacy, health, education and income) were generally higher downstream. Overall, Human Development Index was negatively correlated with the percentage of natural ecosystems in the watershed, especially in the upper and lower watershed regions. Our results indicate that natural capital must be fully considered in projections for increasing human development, so that natural resources can be preserved and managed adequately while sustaining intergenerational well-being.

  2. Chiral methyl-branched pheromones.

    Science.gov (United States)

    Ando, Tetsu; Yamakawa, Rei

    2015-07-01

    Insect pheromones are some of the most interesting natural products because they are utilized for interspecific communication between various insects, such as beetles, moths, ants, and cockroaches. A large number of compounds of many kinds have been identified as pheromone components, reflecting the diversity of insect species. While this review deals only with chiral methyl-branched pheromones, the chemical structures of more than one hundred non-terpene compounds have been determined by applying excellent analytical techniques. Furthermore, their stereoselective syntheses have been achieved by employing trustworthy chiral sources and ingenious enantioselective reactions. The information has been reviewed here not only to make them available for new research but also to understand the characteristic chemical structures of the chiral pheromones. Since biosynthetic studies are still limited, it might be meaningful to examine whether the structures, particularly the positions and configurations of the branched methyl groups, are correlated with the taxonomy of the pheromone producers and also with the function of the pheromones in communication systems.

  3. Robust spinal neuroinflammation mediates mechanical allodynia in Walker 256 induced bone cancer rats

    Directory of Open Access Journals (Sweden)

    Mao-Ying Qi-Liang

    2012-05-01

    Full Text Available Abstract It has been reported that remarkable and sustained activation of astrocytes and/or microglia occurs in cancer induced pain (CIP, which is different from neuropathic and inflammatory pain. The present study was designed to investigate the role of spinal Toll-like receptor 4 (TLR4 induced glial neuroinflammation in cancer induced pain using a modified rat model of bone cancer. The rat model of CIP consisted of unilateral intra-tibial injection with Walker 256 mammary gland carcinoma. Nine days after Walker 256 inoculation, a robust activation of both astrocytes and microglia in bilateral spinal dorsal horn was observed together with significant bilateral mechanical allodynia. This neuroinflammation was characterized by enhanced immunostaining of both glial fibrillary acidic protein (GFAP, astrocyte marker and OX-42 (microglia marker, and an elevated level of IL-1β, IL-6 and TNF-α mRNA. I.t. administration of fluorocitrate (an inhibitor of glial metabolism, 1 nmol or minocycline (an inhibitor of microglia, 100 μg has significant anti-allodynic effects on day 12 after Walker 256 inoculation. Naloxone (a nonstereoselective TLR4 signaling blocker, 60 μg, i.t. also significantly alleviated mechanical allodynia and simultaneously blocked the increased inflammatory cytokine mRNA. The results suggested that spinal TLR4 might play an important role in the sustained glial activation that critically contributed to the robust and sustained spinal neuroinflammation in CIP. This result could potentially help clinicians and researchers to better understand the mechanism of complicated cancer pain.

  4. The influence of septal lesions on sodium and water retention induced by Walker 256 tumor

    Directory of Open Access Journals (Sweden)

    F. Guimarães

    1999-03-01

    Full Text Available In the course of studies on the effects of septal area lesions on neuroimmunomodulation and Walker 256 tumor development, it was observed that tumor-induced sodium and water retention was less marked in lesioned than in non-lesioned rats. In the present study possible mechanisms involved in this phenomenon were investigated. The experiments were performed in septal-lesioned (LW; N = 15 and sham-operated (SW; N = 7 8-week-old male Wistar rats, which received multifocal simultaneous subcutaneous (sc inoculations of Walker 256 tumor cells about 30 days after the stereotaxic surgery. Control groups (no tumor, sham-operated food-restricted (SFR, N = 7 and lesioned food-restricted (LFR, N = 10 were subjected to a feeding pattern similar to that observed in tumor-bearing animals. Multifocal inoculation of Walker 256 tumor rapidly induces anorexia, which is paradoxically accompanied by an increase in body weight, as a result of renal Na+ and fluid retention. These effects of the tumor were also seen in LW rats, although the rise in fractional sodium balance during the early clinical period was significantly smaller than in SW rats (day 4: SW = 47.6 ± 6.4% and LW = 13.8 ± 5.2%; day 5: SW = 57.5 ± 3.5% and LW = 25.7 ± 4.8%; day 6: SW = 54.4 ± 3.8% and LW = 32.1 ± 4.4%; P<0.05, suggesting a temporary reduction in tumor-induced sodium retention. In contrast, urine output was significantly reduced in SW rats and increased in LW rats (LW up to -0.85 and SW up to 4.5 ml/100 g body weight, with no change in osmolar excretion. These temporary changes in the tumor's effects on LW rats may reflect a "reversal" of the secondary central antidiuretic response induced by the tumor (from antidiuretic to diuretic.

  5. Phosphorus and soil development: does the Walker and Syers model apply to semiarid ecosystems?

    Science.gov (United States)

    Selmants, Paul C; Hart, Stephen C

    2010-02-01

    The Walker and Syers model of phosphorus (P) transformations during pedogenesis is widely accepted for the development of humid ecosystems, but long-term P dynamics of more arid ecosystems remain poorly understood. We tested the Walker and Syers model in semiarid piñon-juniper woodlands by measuring soil P fractions under tree canopies and in intercanopy spaces along a well-constrained, approximately 3000 ka (1 ka = 1000 years) volcanic substrate age gradient in northern Arizona, USA. The various pools of soil P behaved largely as predicted; total soil P and primary mineral P declined consistently with substrate age, labile inorganic P increased early in soil development and then declined at later stages, and organic phosphorus increased consistently across the chronosequence. Within each site, soils under tree canopies tended to have higher concentrations of labile and intermediately available P fractions compared to intercanopy soils. However, the degree of spatial heterogeneity conferred by tree islands was moderated by the stage of soil development. In contrast, tree islands had no influence on within-site distribution of more recalcitrant soil P pools, which appear to be controlled solely by the stage of pedogenesis. Coincident with declines in total P, primary mineral P, and labile inorganic P, we found that phosphatase enzyme activity increased with substrate age; a result consistent with greater ecosystem-level P demand on older, more highly weathered substrates. Our results suggest that, compared to humid climates, reduced inputs of water, energy, and acidity to semiarid ecosystems slow the rate of change in P fractions during pedogenesis, but the overall pattern remains consistent with the Walker and Syers model. Furthermore, our data imply that pedogenic change may be an important factor controlling the spatial distribution of labile P pools in semiarid ecosystems. Taken together, these data should both broaden and unify terrestrial ecosystem

  6. Three Different Methods of Estimating LAI in a Small Watershed

    Science.gov (United States)

    Speckman, H. N.; Ewers, B. E.; Beverly, D.

    2015-12-01

    Leaf area index (LAI) is a critical input of models that improve predictive understanding of ecology, hydrology, and climate change. Multiple techniques exist to quantify LAI, most of which are labor intensive, and all often fail to converge on similar estimates. . Recent large-scale bark beetle induced mortality greatly altered LAI, which is now dominated by younger and more metabolically active trees compared to the pre-beetle forest. Tree mortality increases error in optical LAI estimates due to the lack of differentiation between live and dead branches in dense canopy. Our study aims to quantify LAI using three different LAI methods, and then to compare the techniques to each other and topographic drivers to develop an effective predictive model of LAI. This study focuses on quantifying LAI within a small (~120 ha) beetle infested watershed in Wyoming's Snowy Range Mountains. The first technique estimated LAI using in-situ hemispherical canopy photographs that were then analyzed with Hemisfer software. The second LAI estimation technique was use of the Kaufmann 1982 allometrerics from forest inventories conducted throughout the watershed, accounting for stand basal area, species composition, and the extent of bark beetle driven mortality. The final technique used airborne light detection and ranging (LIDAR) first DMS returns, which were used to estimating canopy heights and crown area. LIDAR final returns provided topographical information and were then ground-truthed during forest inventories. Once data was collected, a fractural analysis was conducted comparing the three methods. Species composition was driven by slope position and elevation Ultimately the three different techniques provided very different estimations of LAI, but each had their advantage: estimates from hemisphere photos were well correlated with SWE and snow depth measurements, forest inventories provided insight into stand health and composition, and LIDAR were able to quickly and

  7. On the scalar particle creation by electromagnetic fields in Robertson–Walker spacetime

    Directory of Open Access Journals (Sweden)

    Kenan Sogut

    2015-12-01

    Full Text Available In the present paper, we obtained the scalar particle creation number density by using the Klein–Gordon equation coupled to the electromagnetic fields in the Robertson–Walker spacetime with the help of the Bogoliubov transformation method. We analyzed the resulting expression for the effect of a time-dependent electric field and a constant magnetic field on the particle production rate and found that the strong time-dependent electric field amplifies the particle creation and the magnetic field reduces the rate, in accordance with the previous findings.

  8. Generalized Yule-walker and two-stage identification algorithms for dual-rate systems

    Institute of Scientific and Technical Information of China (English)

    Feng DING

    2006-01-01

    In this paper, two approaches are developed for directly identifying single-rate models of dual-rate stochastic systems in which the input updating frequency is an integer multiple of the output sampling frequency. The first is the generalized Yule-Walker algorithm and the second is a two-stage algorithm based on the correlation technique. The basic idea is to directly identify the parameters of underlying single-rate models instead of the lifted models of dual-rate systems from the dual-rate input-output data, assuming that the measurement data are stationary and ergodic. An example is given.

  9. Spontaneous Compactification to Robertson-Walker Universe Due To Dynamical Torsion

    CERN Document Server

    Malyshenko, V O; Malyshenko, Viktoria; Ricoy, Domingo Marin

    1997-01-01

    We investigate multidimensional gravity with the Gauss-Bonnet term and with torsion on the space of extra dimensions chosen to be the group manifold of a simple Lie group. We take the Robertson-Walker ansatz for the 4-dimensional space-time and study the potential of a dilaton and torsion fields. It is shown that for certain values of the parameters of the initial theory the potential has classically stable minima, corresponding to the spontaneous compactification of the extra dimensions. However, these minima have zero torsion.

  10. Electric-field-controlled suppression of Walker breakdown and chirality switching in magnetic domain wall motion

    Science.gov (United States)

    Chen, Hong-Bo; Li, You-Quan

    2016-07-01

    We theoretically study the dynamics of a magnetic domain wall controlled by an electric field in the presence of the spin flexoelectric interaction. We reveal that this interaction generates an effective spin torque and results in significant changes in the current-driven domain wall motion. In particular, the electric field can stabilize the domain wall motion, leading to strong suppression of the current-induced Walker breakdown and thus allowing a higher maximum wall velocity. We can furthermore use this electric-field control to efficiently switch the chirality of a moving domain wall in the steady regime.

  11. Transplantation of Local Nets and Geometric Modular Action on Robertson-Walker Space-Times

    CERN Document Server

    Buchholz, D; Summers, S J; Buchholz, Detlev; Mund, Jens; Summers, Stephen J.

    2001-01-01

    A novel method of transplanting algebras of observables from de Sitter space to a large class of Robertson-Walker space-times is exhibited. It allows one to establish the existence of an abundance of local nets on these spaces which comply with a recently proposed condition of geometric modular action. The corresponding modular symmetry groups appearing in these examples also satisfy a condition of modular stability, which has been suggested as a substitute for the requirement of positivity of the energy in Minkowski space. Moreover, they exemplify the conjecture that the modular symmetry groups are generically larger than the isometry and conformal groups of the underlying space-times.

  12. Encounter distribution of two random walkers on a finite one-dimensional interval

    Energy Technology Data Exchange (ETDEWEB)

    Tejedor, Vincent; Schad, Michaela; Metzler, Ralf [Physics Department, Technical University of Munich, James Franck Strasse, 85747 Garching (Germany); Benichou, Olivier; Voituriez, Raphael, E-mail: metz@ph.tum.de [Laboratoire de Physique Theorique de la Matiere Condensee (UMR 7600), Universite Pierre et Marie Curie, 4 Place Jussieu, 75255 Paris Cedex (France)

    2011-09-30

    We analyse the first-passage properties of two random walkers confined to a finite one-dimensional domain. For the case of absorbing boundaries at the endpoints of the interval, we derive the probability that the two particles meet before either one of them becomes absorbed at one of the boundaries. For the case of reflecting boundaries, we obtain the mean first encounter time of the two particles. Our approach leads to closed-form expressions that are more easily tractable than a previously derived solution in terms of the Weierstrass' elliptic function. (paper)

  13. The modified Yule-Walker method for α-stable time series models

    Science.gov (United States)

    Kruczek, Piotr; Wyłomańska, Agnieszka; Teuerle, Marek; Gajda, Janusz

    2017-03-01

    This paper discusses the problem of parameters estimation for stable periodic autoregressive (PAR) time series. Considered models generalize popular and widely accepted autoregressive (AR) time series. By examining measures of dependence for α-stable processes, first we introduce new empirical estimator of autocovariation for α-stable sequences. Based on this approach we generalize Yule-Walker method for estimation of parameter for PAR time series. Thus we fill a gap in estimation methods for non-Gaussian models. We test proposed procedure and show its consistency. Moreover, we use our approach to model real empirical data thus showing usefulness of heavy tailed models in statistical modelling.

  14. Synthesis of benzoxazole derivatives of honokiol as insecticidal agents against Mythimna separata Walker.

    Science.gov (United States)

    Yang, Chun; Zhi, Xiaoyan; Xu, Hui

    2015-01-01

    A series of novel benzoxazole compounds derived from a naturally occurring neolignan honokiol were prepared. Their insecticidal activity was tested against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker) in vivo. Most of the tested derivatives exhibited more potential insecticidal activity than their precursor honokiol at the concentration of 1mg/mL. Especially compound 6e, containing 4-acetyloxyphenyl groups at the C8 and C8' positions, displayed the most potent insecticidal activity with the final mortality rate of 62.1%.

  15. Inhomogeneous Viscous Fluids in a Friedmann-Robertson-Walker (FRW Universe

    Directory of Open Access Journals (Sweden)

    Ratbay Myrzakulov

    2013-07-01

    Full Text Available We give a brief review of some aspects of inhomogeneous viscous fluids in a flat Friedmann-Robertson-Walker Universe. In general, it is pointed out that several fluid models may bring the future Universe evolution to become singular, with the appearance of the so-called Big Rip scenario. We investigate the effects of fluids coupled with dark matter in a de Sitter Universe, by considering several cases. Due to this coupling, the coincidence problem may be solved, and if the de Sitter solution is stable, the model is also protected against the Big Rip singularity.

  16. Gravitational waves in Friedman-Lemaitre-Robertson-Walker cosmology, material perturbations and the Huygens principle

    CERN Document Server

    Kulczycki, Wojciech

    2016-01-01

    We analyze propagation equations for the polar modes of gravitational waves in cosmological space-times. We prove that polar gravitational waves must perturb --- unlike axial modes --- the material content of the Friedman-Lemaitre-Robertson-Walker spacetimes. The whole gravitational dynamics reduces to the single "master equation" that has the same form as for axial modes. That allows us to conclude that the status of the Huygens principle is the same for axial and gravitational waves. In particular, this principle is valid exactly in radiation spacetimes with the vanishing cosmological constant, and it is broken otherwise.

  17. Very severe spinal muscular atrophy: Type 0 with Dandy-Walker variant

    Directory of Open Access Journals (Sweden)

    Geeta Gathwala

    2014-01-01

    Full Text Available Spinal muscular atrophy (SMA is an autosomal recessive neuromuscular disease characterized by degeneration of alpha motor neurons in the spinal cord, resulting in progressive proximal muscle weakness and paralysis. In addition to the three classical SMA types, a new form known as type 0 with intrauterine onset, profound hypotonia and a progressive and early fatal course has been described. Herein we report a case of type 0 SMA with a Dandy Walker variant anomaly, which has not hitherto been reported in the world literature.

  18. Tai Lands and Thailand. Community and State in Southeast Asia, Andrew Walker (éd.

    Directory of Open Access Journals (Sweden)

    Olivier Evrard

    2011-01-01

    Full Text Available Voici un ouvrage à lire en commençant par la fin, car l’argument principal se trouve exposé de façon plus claire et convaincante dans la conclusion que dans l’introduction. Pour Andrew Walker, une conception erronnée de la notion de communauté prévaut aujourd’hui parmi les universitaires et les ONG thaïs et elle explique en partie les tensions sociales et politiques que connaît la Thaïlande depuis 2006. Appartenance locale, économie de subsistance, maintien des savoirs traditionnels  : la com...

  19. Global surgery formula for the Casson-Walker invariant (AM-140)

    CERN Document Server

    Lescop, Christine

    2014-01-01

    This book presents a new result in 3-dimensional topology. It is well known that any closed oriented 3-manifold can be obtained by surgery on a framed link in S 3. In Global Surgery Formula for the Casson-Walker Invariant, a function F of framed links in S 3 is described, and it is proven that F consistently defines an invariant, lamda (l), of closed oriented 3-manifolds. l is then expressed in terms of previously known invariants of 3-manifolds. For integral homology spheres, l is the invariant introduced by Casson in 1985, which allowed him to solve old and famous questions in 3-dimensional

  20. A KMS-like state of Hadamard type on Robertson-Walker spacetimes and its time evolution

    CERN Document Server

    Trucks, M

    1998-01-01

    In this work we define a new state on the Weyl algebra of the free massive scalar Klein-Gordon field on a Robertson-Walker spacetime and prove that it is a Hadamard state. The state is supposed to approximate a thermal equilibrium state on a Robertson-Walker spacetime and we call it an adiabatic KMS state. This opens the possibility to do quantum statistical mechanics on Robertson-Walker spacetimes in the algebraic framework and the analysis of the free Bose gas on Robertson-Walker spacetimes. The state reduces to an adiabatic vacuum state if the temperature is zero and it reduces to the usual KMS state if the scaling factor in the metric of the Robertson-Walker spacetime is constant. In the second part of our work we discuss the time evolution of adiabatic KMS states. The time evolution is described in terms of semigroups. We prove the existence of a propagator on the classical phase space. This defines a time evolution on the one-particle Hilbert space. We use this time evolution to analyze the evolution of...

  1. Pendulum Walker

    Science.gov (United States)

    2007-03-11

    Cartesian to cylindrical θ v r x y coordinates2. The velocity, v, we are interested is along the y-direction and is given by cosv rθ θ= & so if r=1...then cosv θ θ= & (7) We know from past work that (recall that θ& is negative): 2 cosEθ θ= − +& (8) Substituting (8) into (7), we obtain: 2...cos cosv E θ θ= − + (9) We can see a graph of this function in Figure 6. Basically, we get a cosine penalty as we approach 3 2 π from the left or

  2. Climate change and watershed mercury export in a Coastal Plain watershed

    Science.gov (United States)

    Heather Golden; Christopher D. Knightes; Paul A. Conrads; Toby D. Feaster; Gary M. Davis; Stephen T. Benedict; Paul M. Bradley

    2016-01-01

    Future changes in climatic conditions may affect variations in watershed processes (e.g., hydrological, biogeochemical) and surface water quality across a wide range of physiographic provinces, ecosystems, and spatial scales. How such climatic shifts will impact watershed mercury (Hg) dynamics and hydrologically-driven Hg transport is a significant concern.

  3. Branching diffusions in random environment

    CERN Document Server

    Böinghoff, Christian

    2011-01-01

    We consider the diffusion approximation of branching processes in random environment (BPREs). This diffusion approximation is similar to and mathematically more tractable than BPREs. We obtain the exact asymptotic behavior of the survival probability. As in the case of BPREs, there is a phase transition in the subcritical regime due to different survival opportunities. In addition, we characterize the process conditioned to never go extinct and establish a backbone construction. In the strongly subcritical regime, mean offspring numbers are increased but still subcritical in the process conditioned to never go extinct. Here survival is solely due to an immortal individual, whose offspring are the ancestors of additional families. In the weakly subcritical regime, the mean offspring number is supercritical in the process conditioned to never go extinct. Thus this process survives with positive probability even if there was no immortal individual.

  4. Branching process models of cancer

    CERN Document Server

    Durrett, Richard

    2015-01-01

    This volume develops results on continuous time branching processes and applies them to study rate of tumor growth, extending classic work on the Luria-Delbruck distribution. As a consequence, the authors calculate the probability that mutations that confer resistance to treatment are present at detection and quantify the extent of tumor heterogeneity. As applications, the authors evaluate ovarian cancer screening strategies and give rigorous proofs for results of Heano and Michor concerning tumor metastasis. These notes should be accessible to students who are familiar with Poisson processes and continuous time. Richard Durrett is mathematics professor at Duke University, USA. He is the author of 8 books, over 200 journal articles, and has supervised more than 40 Ph.D. students. Most of his current research concerns the applications of probability to biology: ecology, genetics, and most recently cancer.

  5. Stabilization of Branching Queueing Networks

    CERN Document Server

    Brázdil, Tomáš

    2011-01-01

    Queueing networks are gaining attraction for the performance analysis of parallel computer systems. A Jackson network is a set of interconnected servers, where the completion of a job at server i may result in the creation of a new job for server j. We propose to extend Jackson networks by "branching" and by "control" features. Both extensions are new and substantially expand the modelling power of Jackson networks. On the other hand, the extensions raise computational questions, particularly concerning the stability of the networks, i.e, the ergodicity of the underlying Markov chain. We show for our extended model that it is decidable in polynomial time if there exists a controller that achieves stability. Moreover, if such a controller exists, one can efficiently compute a static randomized controller which stabilizes the network in a very strong sense; in particular, all moments of the queue sizes are finite.

  6. Lessons From Watershed-Based Climate Smart Agricultural Practices In Jogo-Gudedo Watershed Ethiopia

    Directory of Open Access Journals (Sweden)

    Abera Assefa

    2015-08-01

    Full Text Available Abstract Land degradation is the most chronic problem in the Ethiopia. Soil erosion and denudation of vegetation covers are tending to enlarge the area of degraded and west land in semi-arid watersheds. It is therefore watershed management is believed as a holistic approach to create a climate smart landscape that integrate forestry agriculture pasture and soil water management with an objective of sustainable management of natural resources to improve livelihood. This approach pursues to promote interactions among multiple stakeholders and their interests within and between the upstream and downstream locations of a watershed. Melkassa Agricultural Research Centre MARC has been implementing integrated watershed management research project in the Jogo-gudedo watershed from 2010-2014 and lessons from Jogo-gudedo watershed are presented in this research report. Participatory action research PAR was implemented on Soil and Water Conservation SWC area enclosure Agroforestry AF Conservation Tillage CT energy saving stove drought resistance crop varieties in the Jogo-gudedo watershed. Empirical research and action research at plot level and evaluation of introduced technologies with farmers through experimental learning approach and documentation were employed. The participatory evaluation and collective action of SWC and improved practices brought high degree of acceptance of the practices and technologies. This had been ratified by the implementation of comprehensive watershed management action research which in turn enabled to taste and exploit benefits of climate-smart agricultural practices. Eventually significant reduction on soil loss and fuel wood consumption improvements on vegetation cover and crop production were quantitatively recorded as a good indicator and success. Field visit meetings trainings and frequent dialogues between practitioners and communities at watershed level have had a help in promoting the climate smart agriculture

  7. Dandy-Walker syndrome in adult mimicking myasthenia gravis Síndrome de Dandy-Walker em adulto simulando miastenia gravis

    Directory of Open Access Journals (Sweden)

    Juliana Cardoso

    2007-03-01

    Full Text Available The Dandy-Walker syndrome (DWS is a rare posterior fossa malformation. The DWS can occur associated with other brain or systemic malformations, but ocular abnormalities in this disease are rare and clinical findings mimicking myasthenia gravis have not been described to date. We report a 23-year-old woman who presented mild limitation of the ocular movements with progressive palpebral ptosis, which changed in intensity during the day. The investigation showed negative anti-acetylcholine receptor antibody, repetitive nerve stimulation and "Tensilon test", but the brain magnetic resonance image reveals DWS with hydrocephalus associated with calosal dysgenesis. The characteristic of disease, clinical manifestations and pathologic features, specially the clinical evaluation of ocular abnormalities in suspicion of DWS, including the MG in differential diagnosis are discussed.A síndrome de Dandy-Walker (DWS é uma rara malformação da fossa posterior que pode ocorrer associada com outras malformações cerebrais ou sistêmicas. As alterações oculares são raras e as manifestações clínicas, simulando miastenia gravis (MG, não foram descritas até o momento. Descrevemos uma mulher de 23 anos apresentando discreta limitação da movimentação ocular com progressiva ptose palpebral que mudava de intensidade durante o dia. A investigação mostrou negativos o anticorpo anti-receptor de acetilcolina, a estimulação nervosa repetitiva e o "teste do Tensilon", porém a ressonância magnética de crânio revelou DWS com hidrocefalia associada à disgenesia de corpo caloso. As características da doença, manifestações clínicas e patológicas, especialmente a avaliação clínica de anormalidade ocular na suspeita de DWS serão discutidas, incluindo a MG no diagnóstico diferencial.

  8. Vegetation survey of PEN Branch wetlands

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizes a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.

  9. Simultaneous confidence bands for Yule-Walker estimators and order selection

    CERN Document Server

    Jirak, Moritz

    2012-01-01

    Let $\\{X_k,k\\in{\\mathbb{Z}}\\}$ be an autoregressive process of order $q$. Various estimators for the order $q$ and the parameters ${\\bolds \\Theta}_q=(\\theta_1,...,\\theta_q)^T$ are known; the order is usually determined with Akaike's criterion or related modifications, whereas Yule-Walker, Burger or maximum likelihood estimators are used for the parameters ${\\bolds\\Theta}_q$. In this paper, we establish simultaneous confidence bands for the Yule--Walker estimators $\\hat{\\theta}_i$; more precisely, it is shown that the limiting distribution of ${\\max_{1\\leq i\\leq d_n}}|\\hat{\\theta}_i-\\theta_i|$ is the Gumbel-type distribution $e^{-e^{-z}}$, where $q\\in\\{0,...,d_n\\}$ and $d_n=\\mathcal {O}(n^{\\delta})$, $\\delta >0$. This allows to modify some of the currently used criteria (AIC, BIC, HQC, SIC), but also yields a new class of consistent estimators for the order $q$. These estimators seem to have some potential, since they outperform most of the previously mentioned criteria in a small simulation study. In particul...

  10. Walker 256 Tumor Growth Suppression by Crotoxin Involves Formyl Peptide Receptors and Lipoxin A4

    Science.gov (United States)

    Brigatte, Patrícia; Faiad, Odair Jorge; Ferreira Nocelli, Roberta Cornélio; Landgraf, Richardt G.; Palma, Mario Sergio; Cury, Yara; Curi, Rui; Sampaio, Sandra Coccuzzo

    2016-01-01

    We investigated the effects of Crotoxin (CTX), the main toxin of South American rattlesnake (Crotalus durissus terrificus) venom, on Walker 256 tumor growth, the pain symptoms associated (hyperalgesia and allodynia), and participation of endogenous lipoxin A4. Treatment with CTX (s.c.), daily, for 5 days reduced tumor growth at the 5th day after injection of Walker 256 carcinoma cells into the plantar surface of adult rat hind paw. This observation was associated with inhibition of new blood vessel formation and decrease in blood vessel diameter. The treatment with CTX raised plasma concentrations of lipoxin A4 and its natural analogue 15-epi-LXA4, an effect mediated by formyl peptide receptors (FPRs). In fact, the treatment with Boc-2, an inhibitor of FPRs, abolished the increase in plasma levels of these mediators triggered by CTX. The blockage of these receptors also abolished the inhibitory action of CTX on tumor growth and blood vessel formation and the decrease in blood vessel diameter. Together, the results herein presented demonstrate that CTX increases plasma concentrations of lipoxin A4 and 15-epi-LXA4, which might inhibit both tumor growth and formation of new vessels via FPRs. PMID:27190493

  11. A class of almost equilibrium states in Robertson-Walker spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Kueskue, Muharrem

    2008-11-06

    In quantum field theory in curved spacetimes the construction of the algebra of observables of linear fields is today well understood. However, it remains a non-trivial task to construct physically meaningful states on the algebra. For instance, we are in the unsatisfactory situation that there exist no examples of states suited to describe local thermal equilibrium in a non-stationary spacetime. In this thesis, we construct a class of states for the Klein-Gordon field in Robertson-Walker spacetimes, which seem to provide the first example of thermal states in a spacetime without time translation symmetry. More precisely, in the setting of real, linear, scalar fields in Robertson-Walker spacetimes we define on the set of homogeneous, isotropic, quasi-free states a free energy functional that is based on the averaged energy density measured by an isotropic observer along his worldline. This functional is well defined and lower bounded by a suitable quantum energy inequality. Subsequently, we minimize this functional and obtain states that we interpret as 'almost equilibrium states'. It turns out that the states of low energy are the ground states of the almost equilibrium states. Finally, we prove that the almost equilibrium states satisfy the Hadamard condition, which qualifies them as physically meaningful states. (orig.)

  12. Determining the Walker exponent and developing a modified Smith-Watson-Topper parameter model

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Zhiqiang; Huang, Hong Zhong; Wang, Hai Kun; Gao, Huiying; Zuo, Fang Jun [University of Electronic Science and Technology of China, Chengdu (China)

    2016-03-15

    Mean stress effects significantly influence the fatigue life of components. In general, tensile mean stresses are known to reduce the fatigue life of components, whereas compressive mean stresses are known to increase it. To date, various methods that account for mean stress effects have been studied. In this research, considering the high accuracy of mean stress correction and the difficulty in obtaining the material parameter of the Walker method, a practical method is proposed to describe the material parameter of this method. The test data of various materials are then used to verify the proposed practical method. Furthermore, by applying the Walker material parameter and the Smith-Watson-Topper (SWT) parameter, a modified strain-life model is developed to consider sensitivity to mean stress of materials. In addition, three sets of experimental fatigue data from super alloy GH4133, aluminum alloy 7075-T651, and carbon steel are used to estimate the accuracy of the proposed model. A comparison is also made between the SWT parameter method and the proposed strainlife model. The proposed strain-life model provides more accurate life prediction results than the SWT parameter method.

  13. Confined Random Walkers in Dimensions Higher Than One and Analysis of Transmission of Infection in Epidemics

    CERN Document Server

    Sugaya, S

    2016-01-01

    A pair of random walkers, the motion of each of which in two dimensions is confined spatially by the action of a quadratic potential centered at different locations for the two walks, are analyzed in the context of reaction-diffusion. The application sought is to the process of transmission of infection in epidemics. The walkers are animals such as rodents in considerations of the Hantavirus epidemic, infected or susceptible, the reaction is the transmission of infection, and the confining potential represents the tendency of the animals to stay in the neighborhood of their home range centers. Calculations are based on a recently developed formalism (Kenkre and Sugaya, Bull. Math. Bio. 76, 3016 (2014)) structured around analytic solutions of a Smoluchowski equation and one of its aims is the resolution of peculiar but well-known problems of reaction-diffusion theory in 2-dimensions. In the present analysis, reaction occurs not at points but in spatial regions of dimensions larger than 0. The analysis uncovers...

  14. Anestesia em criança com síndrome de Walker-Warburg

    Directory of Open Access Journals (Sweden)

    Emine Arzu Kose

    2014-04-01

    Full Text Available Justificativa e objetivos: A síndrome de Walker-Warburg é uma distrofia muscular autossômica recessiva congênita rara, manifestada pelo sistema nervoso central com malformações oculares e possível envolvimento de vários sistemas. O diagnóstico é estabelecido pela presença de quatro critérios: distrofia muscular congênita, lisencefalia tipo II, malformação cerebelar e malformação da retina. A maioria das crianças com a síndrome morre nos primeiros três anos de vida por causa de insuficiência respiratória, pneumonia, convulsões, hipertermia e fibrilação ventricular. Relato de caso: É discutida a conduta anestésica em uma criança do sexo masculino, de dois meses, programada para cirurgia eletiva de derivação ventrículo-peritoneal. Conclusões: Uma abordagem anestésica cuidadosa é necessária por causa do envolvimento de vários sistemas. Relatamos a conduta anestésica em uma criança do sexo masculino de dois meses com síndrome de Walker-Warburg, que foi programada para cirurgia eletiva de derivação ventrículo-peritoneal.

  15. Neimark-Sacker bifurcations and evidence of chaos in a discrete dynamical model of walkers

    Science.gov (United States)

    Rahman, Aminur; Blackmore, Denis

    2016-10-01

    Bouncing droplets on a vibrating fluid bath can exhibit wave-particle behavior, such as being propelled by interacting with its own wave field. These droplets seem to walk across the bath, and thus are dubbed walkers. Experiments have shown that walkers can exhibit exotic dynamical behavior indicative of chaos. While the integro-differential models developed for these systems agree well with the experiments, they are difficult to analyze mathematically. In recent years, simpler discrete dynamical models have been derived and studied numerically. The numerical simulations of these models show evidence of exotic dynamics such as period doubling bifurcations, Neimark--Sacker (N--S) bifurcations, and even chaos. For example, in [Gilet, PRE 2014], based on simulations Gilet conjectured the existence of a supercritical N-S bifurcation as the damping factor in his one-dimensional path model. We prove Gilet's conjecture and more; in fact, both supercritical and subcritical (N-S) bifurcations are produced by separately varying the damping factor and wave-particle coupling for all eigenmode shapes. Then we compare our theoretical results with some previous and new numerical simulations, and find complete qualitative agreement. Furthermore, evidence of chaos is shown by numerically studying a global bifurcation.

  16. Seeing the sky through Hubble's eye: The COSMOS SkyWalker

    CERN Document Server

    Jahnke, K; Koekemoer, A

    2006-01-01

    Large, high-resolution space-based imaging surveys produce a volume of data that is difficult to present to the public in a comprehensible way. While megapixel-sized images can still be printed out or downloaded via the World Wide Web, this is no longer feasible for images with 10^9 pixels (e.g., the Hubble Space Telescope Advanced Camera for Surveys [ACS] images of the Galaxy Evolution from Morphology and SEDs [GEMS] project) or even 10^10 pixels (for the ACS Cosmic Evolution Survey [COSMOS]). We present a Web-based utility called the COSMOS SkyWalker that allows viewing of the huge ACS image data set, even through slow Internet connections. Using standard HTML and JavaScript, the application successively loads only those portions of the image at a time that are currently being viewed on the screen. The user can move within the image by using the mouse or interacting with an overview image. Using an astrometrically registered image for the COSMOS SkyWalker allows the display of calibrated world coordinates f...

  17. Controlled Electronic Transport through Branched Molecular Conductors

    OpenAIRE

    2008-01-01

    Abstract The conductance through a branched conductor placed between two electrodes is analyzed using the Landauer transport formulation within the framework of the single electron, and the tight binding approximations. Terminal side chains are expressed as self energy terms which map the branched conductor onto an effective linear chain Hamiltonian. The effect of uniform side branches on resonant zero-bias conductance is shown to be analytically solvable and particularly simple, w...

  18. Branched silver nanowires as controllable plasmon routers.

    Science.gov (United States)

    Fang, Yurui; Li, Zhipeng; Huang, Yingzhou; Zhang, Shunping; Nordlander, Peter; Halas, Naomi J; Xu, Hongxing

    2010-05-12

    Using polarization dependent scattering spectroscopy, we investigate plasmon propagation on branched silver nanowires. By controlling the polarization of the incident laser light, the wire plasmons can be routed into different wire branches and result in light emission from the corresponding wire ends. This routing behavior is found to be strongly dependent on the wavelength of light. Thus for certain incident polarizations, light of different wavelength will be routed into different branches. The branched nanowire can thus serve as a controllable router and multiplexer in integrated plasmonic circuits.

  19. Current perspectives on shoot branching regulation

    Directory of Open Access Journals (Sweden)

    Cunquan YUAN,Lin XI,Yaping KOU,Yu ZHAO,Liangjun ZHAO

    2015-03-01

    Full Text Available Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.

  20. Networks of companies and branches in Poland

    CERN Document Server

    Chmiel, A M; Sienkiewicz, J; Suchecki, K; Chmiel, Anna M.; Holyst, Janusz A.; Sienkiewicz, Julian; Suchecki, Krzysztof

    2006-01-01

    In this study we consider relations between companies in Poland taking into account common branches they belong to. It is clear that companies belonging to the same branch compete for similar customers, so the market induces correlations between them. On the other hand two branches can be related by companies acting in both of them. To remove weak, accidental links we shall use a concept of threshold filtering for weighted networks where a link weight corresponds to a number of existing connections (common companies or branches) between a pair of nodes.

  1. Haruki Murakami’s Deconstructive Reading of the Myth of Johnnie Walker and Colonel Sanders in Kafka on the Shore

    Directory of Open Access Journals (Sweden)

    Limanta L. S.

    2012-01-01

    Full Text Available This study aims to analyze how Haruki Murakami reads the real icons of Johnnie Walker and Colonel Sanders in Kafka on the Shore deconstructively. First, we will focus on the signification process of the icon, which are to a great extent molded by advertisements, and then on the deconstruction of their signifieds. For the purpose, we will apply Barthes’ idea of myth. We are also interested in revealing how Murakami constructs Johnnie Walker and Colonel Sanders to be characters in the novel. The analysis shows that the construction of the icons through advertisements leads to the creation of their mtyhs, and then Murakami reads them deconstructively to be opposite signifieds.

  2. Nitrogen Saturation in Highly Retentive Watersheds?

    Science.gov (United States)

    Daley, M. L.; McDowell, W. H.

    2009-12-01

    Watershed managers are often concerned with minimizing the amount of N delivered to N-limited estuaries and coastal zones. A major concern is that watersheds might reach N saturation, in which N delivered to coastal zones increases due to declines in the efficiency of N retention despite constant or even reduced N inputs. We have quantified long-term changes in N inputs (atmospheric deposition, imported food and agricultural fertilizers), outputs (N concentration and export) and retention in the urbanizing Lamprey River watershed in coastal NH. Overall, the Lamprey watershed is 70% forested, receives about 13.5 kg N/ha/yr and has a high rate of annual N retention (85%). Atmospheric deposition (8.7 kg/ha/yr) is the largest N input to the watershed. Of the 2.2 kg N/ha/yr exported in the Lamprey River, dissolved organic N (DON) is the dominant form (50% of total) and it varies spatially throughout the watershed with wetland cover. Nitrate accounts for 30% of the N exported, shows a statistically significant increase from 1999 to 2009, and its spatial variability in both concentration and export is related to human population density. In sub-basins throughout the Lamprey, inorganic N retention is high (85-99%), but the efficiency of N retention declines sharply with increased human population density and associated anthropogenic N inputs. N assimilation in the vegetation, denitrification to the atmosphere and storage in the groundwater pool could all be important contributors to the current high rates of N retention. The temporal and spatial patterns that we have observed in nitrate concentration and export are driven by increases in N inputs and impervious surfaces over time, but the declining efficiency of N retention suggests that the watershed may also be reaching N saturation. The downstream receiving estuary, Great Bay, already suffers from low dissolved oxygen levels and eelgrass loss in part due to N loading from the Lamprey watershed. Targeting and reducing

  3. Community DECISIONS: stakeholder focused watershed planning.

    Science.gov (United States)

    Bosch, Darrell; Pease, James; Wolfe, Mary Leigh; Zobel, Christopher; Osorio, Javier; Cobb, Tanya Denckla; Evanylo, Greg

    2012-12-15

    Successful watershed planning can be enhanced by stakeholder involvement in developing and implementing plans that reflect community goals and resource limitations. Community DECISIONS (Community Decision Support for Integrated, On-the-ground Nutrient Reduction Strategies) is a structured decision process to help stakeholders evaluate strategies that reduce watershed nutrient imbalances. A nutrient accounting algorithm and nutrient treatment database provide information on nutrient loadings and costs of alternative strategies to reduce loadings. Stakeholders were asked to formulate goals for the North Fork Shenandoah River Watershed in Virginia and select among strategies to achieve those goals. The Vector Analytic Hierarchy Process was used to rank strategies. Stakeholders preferred a Maximum strategy that included point source upgrades, riparian buffers, no-till corn silage, wheat cover, and bioretention filters in developed areas. Participants generally agreed that the process helped improve communication among stakeholders, was helpful for watershed planning, and should be used for TMDL (Total Maximum Daily Load) planning. Participants suggested more attention be paid to ensuring that all relevant issues are addressed and all information needed to make decisions is available. Watershed planning should provide stakeholders with clear scientific information about physical and socioeconomic processes. However, planning processes must give stakeholders adequate time to consider issues that may not have been addressed by existing scientific models and datasets.

  4. Land protection plan : Bear River Watershed Conservation Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The U.S. Fish and Wildlife Service is establishing a conservation area for the Bear River watershed in Idaho, Utah, and Wyoming. The Bear River Watershed...

  5. DNR Watersheds - DNR Level 04 - HUC 08 - Majors

    Data.gov (United States)

    Minnesota Department of Natural Resources — These data consists of 81 watershed delineations in one seamless dataset of drainage areas called Minnesota Department of Natural Resources (DNR) Major Watersheds....

  6. Protect and Restore Mill Creek Watershed : Annual Report CY 2005.

    Energy Technology Data Exchange (ETDEWEB)

    McRoberts, Heidi

    2006-03-01

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. The Nez Perce Tribe and the Nez Perce National Forest (NPNF) have formed a partnership in completing watershed restoration activities, and through this partnership, more work is accomplished by sharing funding and resources in our effort. The Nez Perce Tribe began watershed restoration projects within the Mill Creek watershed of the South Fork Clearwater River in 2000. Progress has been made in restoring the watershed through excluding cattle from critical riparian areas through fencing. Starting in FY 2002, continuing into 2004, trees were planted in riparian areas in the meadow of the upper watershed. In addition, a complete inventory of culverts at road-stream crossings was completed. Culverts have been prioritized for replacement to accommodate fish passage throughout the watershed, and one high priority culvert was replaced in 2004. Maintenance to the previously built fence was also completed.

  7. How Sustainable is Participatory Watershed Development in India?

    NARCIS (Netherlands)

    Bouma, J.; Soest, van D.P.; Bulte, E.H.

    2007-01-01

    Watershed conservation is widely recognized as a major strategy for rural development throughout the developing world. In India, the apparent success of participatory approaches to watershed development resulted in a decentralization of project planning, implementation, and management to local

  8. US Forest Service Watershed Condition Class and Assessment Status 2011

    Data.gov (United States)

    US Forest Service, Department of Agriculture — The map contains the Watershed Condition Class and assessment status for the assessment year of 2011. The layer is symbolized by the Watershed Condition Class for...

  9. Information Management for the Watershed Approach in the Pacific Northwest

    Science.gov (United States)

    A collection of interviews with leaders and key participants in the statewide watershed approach activities in the State of Washington. Additionally, there are reviews of Washington’s statewide watershed activities in a case study fashion.

  10. Application of watershed modeling system (WMS) for integrated management of a watershed in Turkey.

    Science.gov (United States)

    Erturk, Ali; Gurel, Melike; Baloch, Mansoor Ahmed; Dikerler, Teoman; Varol, Evren; Akbulut, Neslihan; Tanik, Aysegul

    2006-01-01

    Watershed models, that enable the quantification of current and future pollution loading impacts, are essential tools to address the functions and conflicts faced in watershed planning and management. In this study, the Watershed Modeling System (WMS) version 7.1 was used for the delineation of boundaries of Koycegiz Lake-Dalyan Lagoon watershed located in the southwest of Turkey at the Mediterranean Sea coast. A Digital Elevation Model (DEM) was created for one of the major streams of the watershed, namely, Kargicak Creek by using WMS, and DEM data were further used to extract stream networks and delineate the watershed boundaries. Typical properties like drainage areas, characteristic length and slope of sub-drainage areas have also been determined to be used as model inputs in hydrological and diffuse pollution modeling. Besides, run-off hydrographs for the sub-drainages have been calculated using the Rational Method, which produces valuable data for calculating the time variable inflow and input pollution loads to be further utilized in the future water quality models of the Creek. Application of WMS in the study has shown that, it is capable to visualize the results in establishing watershed management strategies.

  11. Identifying and Classifying Pollution Hotspots to Guide Watershed Management in a Large Multiuse Watershed.

    Science.gov (United States)

    Su, Fangli; Kaplan, David; Li, Lifeng; Li, Haifu; Song, Fei; Liu, Haisheng

    2017-03-03

    In many locations around the globe, large reservoir sustainability is threatened by land use change and direct pollution loading from the upstream watershed. However, the size and complexity of upstream basins makes the planning and implementation of watershed-scale pollution management a challenge. In this study, we established an evaluation system based on 17 factors, representing the potential point and non-point source pollutants and the environmental carrying capacity which are likely to affect the water quality in the Dahuofang Reservoir and watershed in northeastern China. We used entropy methods to rank 118 subwatersheds by their potential pollution threat and clustered subwatersheds according to the potential pollution type. Combining ranking and clustering analyses allowed us to suggest specific areas for prioritized watershed management (in particular, two subwatersheds with the greatest pollution potential) and to recommend the conservation of current practices in other less vulnerable locations (91 small watersheds with low pollution potential). Finally, we identified the factors most likely to influence the water quality of each of the 118 subwatersheds and suggested adaptive control measures for each location. These results provide a scientific basis for improving the watershed management and sustainability of the Dahuofang reservoir and a framework for identifying threats and prioritizing the management of watersheds of large reservoirs around the world.

  12. Watershed modeling and monitoring for assessing nutrient ...

    Science.gov (United States)

    Presentation for the American Water Works Association Water Sustainability Conference. The presentation highlights latest results from water quality trading research conducted by ORD using the East Fork Watershed in Southwestern Ohio as a case study. The watershed has a nutrient enrichment problem that is creating harmful algal blooms in a reservoir used for drinking water and recreation. Innovative modeling and monitoring is combined to understand how to best manage this water quality problem and costs associated with this endeavor. The presentation will provide an overview of the water quality trading feasibility research. The research includes the development and evaluation of innovative modeling and monitoring approaches to manage watersheds for nutrient pollution using a whole systems approach.

  13. Watershed Boundaries, Watershed Boundaries, Published in 2002, 1:4800 (1in=400ft) scale, Iredell County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Watershed Boundaries dataset, published at 1:4800 (1in=400ft) scale as of 2002. It is described as 'Watershed Boundaries'. Data by this publisher are often...

  14. Stochastic transition between turbulent branch and thermodynamic branch of an inhomogeneous plasma

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Mitsuhiro; Itoh, Sanae-I.; Yagi, Masatoshi [Kyushu Univ., Research Institute for Applied Mechanics, Kasuga, Fukuoka (Japan); Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2002-05-01

    Transition phenomena between thermodynamic branch and turbulent branch in submarginal turbulent plasma are analyzed with statistical theory. Time-development of turbulent fluctuation is obtained by numerical simulations of Langevin equation which contains submarginal characteristics. Probability density functions and transition rates between two states are analyzed. Transition from turbulent branch to thermodynamic branch occurs in almost entire region between subcritical bifurcation point and linear stability boundary. (author)

  15. Revisión taxonómica de los géneros Oratha Walker 1863 y Hasodima Butler 1882 (Lepidoptera: Geometridae Taxonomic revision of the genera Oratha Walker 1863 and Hasodima Butler 1882 (Lepidoptera: Geometridae

    Directory of Open Access Journals (Sweden)

    LUIS E PARRA

    2003-03-01

    Full Text Available RESUMEN Los géneros Oratha Walker 1863 y Hasodima Butler 1882 del sur y centro de Chile son revisados y sus especies redefinidas y redescritas. Las especies quedan como sigue: Oratha significata Walker 1863, Hasodima elegans Butler 1882, H. boreas (Butler 1882 comb. nov. y H. bartletti nov. sp. El análisis de los tipos y de la genitalia permite colocar Aconcagua fessa Rindge 1975 en la sinonimia de Aconcagua parva (Butler comb. nov. Se describe e ilustran los adultos, las armaduras genitales y la distribución de las especies. Se entrega una clave para separar las especies de Hasodima. La monofilia de los géneros y sus relaciones con taxa cercanos se discute brevemente.The genera Oratha Walker 1863 and Hasodima Butler 1882 from central and southern Chile are redefined and its species revised and described. The species are Oratha significata Walker 1863, H. elegans Butler 1882, H. boreas (Butler 1882 and H. bartletti sp. nov. The analysis of the types and the genitalia allow placing Aconcagua fessa Rindge in the synonymy of Aconcagua parva (Butler comb. nov. All species and their genitalia and distribution are described and illustrated. A key for species of Hasodima is provided. The monophyly of the genera and its relationships to the allied taxa are briefly discussed.

  16. Regionalization of SWAT Model Parameters for Use in Ungauged Watersheds

    Directory of Open Access Journals (Sweden)

    Indrajeet Chaubey

    2010-11-01

    Full Text Available There has been a steady shift towards modeling and model-based approaches as primary methods of assessing watershed response to hydrologic inputs and land management, and of quantifying watershed-wide best management practice (BMP effectiveness. Watershed models often require some degree of calibration and validation to achieve adequate watershed and therefore BMP representation. This is, however, only possible for gauged watersheds. There are many watersheds for which there are very little or no monitoring data available, thus the question as to whether it would be possible to extend and/or generalize model parameters obtained through calibration of gauged watersheds to ungauged watersheds within the same region. This study explored the possibility of developing regionalized model parameter sets for use in ungauged watersheds. The study evaluated two regionalization methods: global averaging, and regression-based parameters, on the SWAT model using data from priority watersheds in Arkansas. Resulting parameters were tested and model performance determined on three gauged watersheds. Nash-Sutcliffe efficiencies (NS for stream flow obtained using regression-based parameters (0.53–0.83 compared well with corresponding values obtained through model calibration (0.45–0.90. Model performance obtained using global averaged parameter values was also generally acceptable (0.4 ≤ NS ≤ 0.75. Results from this study indicate that regionalized parameter sets for the SWAT model can be obtained and used for making satisfactory hydrologic response predictions in ungauged watersheds.

  17. Watershed Management Optimization Support Tool (WMOST) v2: Theoretical Documentation

    Science.gov (United States)

    The Watershed Management Optimization Support Tool (WMOST) is a decision support tool that evaluates the relative cost-effectiveness of management practices at the local or watershed scale. WMOST models the environmental effects and costs of management decisions in a watershed c...

  18. Guiding principles for management of forested, agricultural, and urban watersheds

    Science.gov (United States)

    Pamela J. Edwards; Jon E. Schoonover; Karl W.J. Williard

    2015-01-01

    Human actions must be well planned and include consideration of their potential influences on water and aquatic ecosystems - such consideration is the foundation of watershed management. Watersheds are the ideal land unit for managing and protecting water resources and aquatic health because watersheds integrate the physical, biological and chemical processes within...

  19. Asymptotics of Simple Branching Populations

    Science.gov (United States)

    Huillet, Thierry; Kłopotowski, Andrzej; Porzio, Anna

    1995-09-01

    In this paper we study a simple deterministic tree structure: an initial individual generates a finite number of offspring, each of which has given integer valued lifetime, iterating the same procedure when dying. Three asymptotic distributions of this asynchronous deterministic branching procedure are considered: the generation distribution, the ability of individuals to generate offspring and the age distribution. Thermodynamic formalism is then developped to reveal the multifractal nature of the mass splitting associated to our process. On considère l'itération d'une structure déterministe arborescente selon laquelle un ancêtre engendre un nombre fini de descendants dont la durée de vie (à valeurs entières) est donnée. Dans un premier temps on s'intéresse aux trois distributions asymptotiques suivantes : répartition des générations, aptitude à engendrer des descendants et répartition selon l'âge. Ensuite nous développons le formalisme thermodynamique pour mettre en évidence le caractère multifractal de la scission d'une masse unitaire associée à cette arborescence.

  20. ECONOMIC ISSUES OF BRANCH PRODUCTION

    Directory of Open Access Journals (Sweden)

    Shamrov K. N.

    2015-05-01

    Full Text Available The article deals with topical questions of economy industry production of rice grain. The need for improving the business efficiency of rice today is dictated by political and economic sanctions, the needs of our society in full substitution of this important product. State stimulation of rice development today is carried out through a complex of economic and administrative activities. The economic measures of the state include: price control on rice price and processing products, support of agricultural producers’ incomes, leasing involving the state, marketing of products, and infrastructure development of the grain market. The system of public administrative measures also includes standardization and certification of grain products, control quality of grain and products of its processing, the quarantine protection, licensing activities organizations, and mandatory statistical account of the rice market. These measures are intended to ensure equal conditions of competition between local and imported rice, to spur investment and expansion of domestic production, increase profitability of rice, allowing the rice enterprises to carry out expensive irrigation systems repairs and capital inputs in lot lend. The article suggests that rice branch industry remains competitive and with abolition of import customs barriers within frameworks WTO. It is necessary to invest more heavily in infrastructure with the aim of improving business efficiency of rice

  1. Wind River Watershed Restoration: 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, Patrick J.

    2001-09-01

    This document represents work conducted as part of the Wind River Watershed Restoration Project during its first year of funding through the Bonneville Power Administration (BPA). The project is a comprehensive effort involving public and private entities seeking to restore water quality and fishery resources in the basin through cooperative actions. Project elements include coordination, watershed assessment, restoration, monitoring, and education. Entities involved with implementing project components are the Underwood Conservation District (UCD), USDA Forest Service (USFS), U.S. Geological Survey--Columbia River Research Lab (USGS-CRRL), and WA Department of Fish & Wildlife (WDFW). Following categories given in the FY1999 Statement of Work, the broad categories, the related objectives, and the entities associated with each objective (lead entity in boldface) were as follows: Coordination--Objective 1: Coordinate the Wind River watershed Action Committee (AC) and Technical Advisory Committee (TAC) to develop a prioritized list of watershed enhancement projects. Monitoring--Objective 2: Monitor natural production of juvenile, smolt, and adult steelhead in the Wind River subbasin. Objective 3: Evaluate physical habitat conditions in the Wind River subbasin. Assessment--Objective 4: Assess watershed health using an ecosystem-based diagnostic model that will provide the technical basis to prioritize out-year restoration projects. Restoration--Objective 5: Reduce road related sediment sources by reducing road densities to less than 2 miles per square mile. Objective 6: Rehabilitate riparian corridors, flood plains, and channel morphology to reduce maximum water temperatures to less than 61 F, to increase bank stability to greater than 90%, to reduce bankfull width to depth ratios to less than 30, and to provide natural levels of pools and cover for fish. Objective 7: Maintain and evaluate passage for adult and juvenile steelhead at artificial barriers. Education

  2. Pore Size Distribution and Methane Equilibrium Conditions at Walker Ridge Block 313, Northern Gulf of Mexico

    Science.gov (United States)

    Bihani, A. D.; Daigle, H.; Cook, A.; Glosser, D.; Shushtarian, A.

    2015-12-01

    Coexistence of three methane phases (liquid (L), gas (G), hydrate (H)) in marine gas hydrate systems may occur according to in-situ pressure, temperature, salinity and pore size. In sediments with salinity close to seawater, a discrete zone of three-phase (3P) equilibrium may occur near the base of the regional hydrate stability zone (RHSZ) due to capillary effects. The existence of a 3P zone influences the location of the bottom-simulating reflection (BSR) and has implications for methane fluxes at the base of the RHSZ. We studied hydrate stability conditions in two wells, WR313-G and WR313-H, at Walker Ridge Block 313 in the northern Gulf of Mexico. We determined pore size distributions (PSD) by constructing a synthetic nuclear magnetic resonance (NMR) relaxation time distribution. Correlations were obtained by non-linear regression on NMR, gamma ray, and bulk density logs from well KC-151 at Keathley Canyon. The correlations enabled construction of relaxation time distributions for WR313-G and WR313-H, which were used to predict PSD through comparison with mercury injection capillary pressure measurements. With the computed PSD, L+H and L+G methane solubility was determined from in-situ pressure and temperature. The intersection of the L+G and L+H curves for various pore sizes allowed calculation of the depth range of the 3P equilibrium zone. As in previous studies at Blake Ridge and Hydrate Ridge, the top of the 3P zone moves upwards with increasing water depth and overlies the bulk 3P equilibrium depth. In clays at Walker Ridge, the predicted thickness of the 3P zone is approximately 35 m, but in coarse sands it is only a few meters due to the difference in absolute pore sizes and the width of the PSD. The thick 3P zone in the clays may explain in part why the BSR is only observed in the sand layers at Walker Ridge, although other factors may influence the presence or absence of a BSR.

  3. Pore size distribution and methane equilibrium conditions at Walker Ridge Block 313, northern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Bihani, Abhishek [University of Texas at Austin; Daigle, Hugh [University of Texas at Austin; Cook, Ann [Ohio State University; Glosser, Deborah [Ohio State University; Shushtarian, Arash [University of Texas at Austin

    2015-12-15

    Coexistence of three methane phases (liquid (L), gas (G), hydrate (H)) in marine gas hydrate systems may occur according to in-situ pressure, temperature, salinity and pore size. In sediments with salinity close to seawater, a discrete zone of three-phase (3P) equilibrium may occur near the base of the regional hydrate stability zone (RHSZ) due to capillary effects. The existence of a 3P zone influences the location of the bottom-simulating reflection (BSR) and has implications for methane fluxes at the base of the RHSZ. We studied hydrate stability conditions in two wells, WR313-G and WR313-H, at Walker Ridge Block 313 in the northern Gulf of Mexico. We determined pore size distributions (PSD) by constructing a synthetic nuclear magnetic resonance (NMR) relaxation time distribution. Correlations were obtained by non-linear regression on NMR, gamma ray, and bulk density logs from well KC-151 at Keathley Canyon. The correlations enabled construction of relaxation time distributions for WR313-G and WR313-H, which were used to predict PSD through comparison with mercury injection capillary pressure measurements. With the computed PSD, L+H and L+G methane solubility was determined from in-situ pressure and temperature. The intersection of the L+G and L+H curves for various pore sizes allowed calculation of the depth range of the 3P equilibrium zone. As in previous studies at Blake Ridge and Hydrate Ridge, the top of the 3P zone moves upwards with increasing water depth and overlies the bulk 3P equilibrium depth. In clays at Walker Ridge, the predicted thickness of the 3P zone is approximately 35 m, but in coarse sands it is only a few meters due to the difference in absolute pore sizes and the width of the PSD. The thick 3P zone in the clays may explain in part why the BSR is only observed in the sand layers at Walker Ridge, although other factors may influence the presence or absence of a BSR.

  4. An archetypal mechanism for branching organogenesis.

    Science.gov (United States)

    Clément, Raphaël; Mauroy, Benjamin

    2014-02-01

    Branched structures are ubiquitous in nature, both in living and non-living systems. While the functional benefits of branching organogenesis are straightforward, the developmental mechanisms leading to the repeated branching of epithelia in surrounding mesoderm remain unclear. Both molecular and physical aspects of growth control seem to play a critical role in shape emergence and maintenance. On the molecular side, the existence of a gradient of growth-promoting ligand between epithelial tips and distal mesenchyme seems to be common to branched organs. On the physical side, the branching process seems to require a mechanism of real-time adaptation to local geometry, as suggested by the self-avoiding nature of branching events. In this paper, we investigate the outcomes of a general three-dimensional growth model, in which epithelial growth is implemented as a function of ligand income, while the mesenchyme is considered as a proliferating viscous medium. Our results suggest that the existence of a gradient of growth-promoting ligand between distal and proximal mesenchyme implies a growth instability of the epithelial sheet, resulting in spontaneous self-avoiding branching morphogenesis. While the general nature of the model prevents one from fitting the development of specific organs, it suggests that few ingredients are actually required to achieve branching organogenesis.

  5. The Chena River Watershed Hydrology Model

    Science.gov (United States)

    2012-04-01

    ER D C/ CR R EL T R -1 2 -1 The Chena River Watershed Hydrology Model C ol d R eg io n s R es ea rc h an d E n gi n ee ri n g La...14 Table 6. Estimated monthly ET using Hargreaves method and pan...using water balance method A generalized water balance for the Chena River watershed can be written as mS P S ET R     (3) where P

  6. Sediment and discharge yields within a minimally disturbed, headwater watershed in North Central Pennsylvania, USA, with an emphasis on Superstorm Sandy

    Science.gov (United States)

    Maloney, Kelly O.; Shull, Dustin R.

    2015-01-01

    We estimated discharge and suspended sediment (SS) yield in a minimally disturbed watershed in North Central Pennsylvania, USA, and compared a typical storm (September storm, 4.80 cm) to a large storm (Superstorm Sandy, 7.47 cm rainfall). Depending on branch, Sandy contributed 9.7–19.9 times more discharge and 11.5–37.4 times more SS than the September storm. During the September storm, the upper two branches accounted for 60.6% of discharge and 88.8% of SS at Lower Branch; during Sandy these percentages dropped to 36.1% for discharge and 30.1% for SS. The branch with close proximity roads had over two-three times per area SS yield than the branch without such roads. Hysteresis loops showed typical clockwise patterns for the September storm and more complicated patterns for Sandy, reflecting the multipeak event. Estimates of SS and hysteresis in minimally disturbed watersheds provide useful information that can be compared spatially and temporally to facilitate management.

  7. Rapid Communication. Tamarixia monesus (Walker (Hym.: Eulophidae parasitoid of Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae in Iran

    Directory of Open Access Journals (Sweden)

    Lotfalizadeh Hossein

    2016-08-01

    Full Text Available Bactericera tremblayi (Wagner, 1961 (Hemiptera: Triozidae is reported on Brassica oleracea var. capitata (Brassicaceae in northwestern Iran. Tamarixia monesus (Walker (Hymenoptera: Chalcidoidea, Eulophidae was reared for the first time on B. tremblayi, and compared with Tamarixia tremblayi, another parasitoid of B. tremblayi. This is a new record of T. monesus from the Middle East.

  8. Description of a new species and subspecies of Idalus Walker from Costa Rica, Honduras and Guatemala (Lepidoptera, Erebidae, Arctiinae, Arctiini)

    Science.gov (United States)

    Espinoza, Bernardo A.; Janzen, Daniel H.; Winnie Hallwachs;  J. Bolling Sullivan

    2013-01-01

    Abstract A new species and subspecies of Idalus Walker are described from Costa Rica, Honduras and Guatemala. Images of males and females and their genitalia are provided. Locality information and distribution maps for Costa Rica and for Guatemala are included. The biology and phylogeny of Idalus are discussed. PMID:23730178

  9. Quantum features derived from the classical model of a bouncer-walker coupled to a zero-point field

    Science.gov (United States)

    Schwabl, H.; Mesa Pascasio, J.; Fussy, S.; Grössing, G.

    2012-05-01

    In our bouncer-walker model a quantum is a nonequilibrium steady-state maintained by a permanent throughput of energy. Specifically, we consider a "particle" as a bouncer whose oscillations are phase-locked with those of the energy-momentum reservoir of the zero-point field (ZPF), and we combine this with the random-walk model of the walker, again driven by the ZPF. Starting with this classical toy model of the bouncer-walker we were able to derive fundamental elements of quantum theory [1]. Here this toy model is revisited with special emphasis on the mechanism of emergence. Especially the derivation of the total energy hslashωo and the coupling to the ZPF are clarified. For this we make use of a sub-quantum equipartition theorem. It can further be shown that the couplings of both bouncer and walker to the ZPF are identical. Then we follow this path in accordance with Ref. [2], expanding the view from the particle in its rest frame to a particle in motion. The basic features of ballistic diffusion are derived, especially the diffusion constant D, thus providing a missing link between the different approaches of our previous works [1, 2].

  10. Quantum features derived from the classical model of a bouncer-walker coupled to a zero-point field

    CERN Document Server

    Schwabl, Herbert; Fussy, Siegfried; Groessing, Gerhard; 10.1088/1742-6596/361/1/012021

    2012-01-01

    In our bouncer-walker model a quantum is a nonequilibrium steady-state maintained by a permanent throughput of energy. Specifically, we consider a "particle" as a bouncer whose oscillations are phase-locked with those of the energy-momentum reservoir of the zero-point field (ZPF), and we combine this with the random-walk model of the walker, again driven by the ZPF. Starting with this classical toy model of the bouncer-walker we were able to derive fundamental elements of quantum theory. Here this toy model is revisited with special emphasis on the mechanism of emergence. Especially the derivation of the total energy hbar.omega and the coupling to the ZPF are clarified. For this we make use of a sub-quantum equipartition theorem. It can further be shown that the couplings of both bouncer and walker to the ZPF are identical. Then we follow this path in accordance with previous work, expanding the view from the particle in its rest frame to a particle in motion. The basic features of ballistic diffusion are der...

  11. Description of a new species and subspecies of Idalus Walker from Costa Rica, Honduras and Guatemala (Lepidoptera, Erebidae, Arctiinae, Arctiini)

    OpenAIRE

    Bernardo Espinoza Sanabria; Daniel Janzen; Winnie Hallwachs; J. Bolling Sullivan

    2013-01-01

    Abstract A new species and subspecies of Idalus Walker are described from Costa Rica, Honduras and Guatemala. Images of males and females and their genitalia are provided. Locality information and distribution maps for Costa Rica and for Guatemala are included. The biology and phylogeny of Idalus are discussed.

  12. Species of the genus Aragara Walker (Diptera: Chloropidae: Chloropinae: Mindini) from China with key to species of the world.

    Science.gov (United States)

    Liu, Xiaoyan; Yang, Ding

    2014-12-12

    The genus Aragara Walker is newly recorded from China. The following two species are described new to science: A. flavaristata sp. nov. and A. menglaensis sp. nov. One species, A. trilineata Cherian, is newly recorded from China, and one new combination, A. sinensis (Yang & Yang), is proposed. A key to world species of genus Aragara is given. 

  13. 77 FR 54567 - Submission for OMB Review; Comment Request: Requirements for Baby-Bouncers and Walker-Jumpers

    Science.gov (United States)

    2012-09-05

    ... for OMB Review; Comment Request: Requirements for Baby-Bouncers and Walker-Jumpers AGENCY: Consumer... seek extension of approval of the collection of information in the requirements for baby-bouncers and...- 0038, or by mail/hand delivery/courier (for paper, disk, or CD-ROM submissions), preferably in five...

  14. Review of the East Palaearctic and North Oriental Psyttalia Walker, with the description of three new species (Hymenoptera, Braconidae, Opiinae)

    NARCIS (Netherlands)

    Wu, Q.; Achterberg, van C.; Tan, J.-L.; Chen, X.-X.

    2016-01-01

    The East Palaearctic and North Oriental species of the genus Psyttalia Walker (Hymenoptera, Braconidae, Opiinae) are reviewed. Three new species are described and illustrated: P. latinervis Wu & van Achterberg, sp. n. and P. majocellata Wu & van Achterberg, sp. n. from China, and P. spectabilis van

  15. 豆天蛾幼虫保藏研究%Study on Preservation of Clanis bilineata Walker Larva

    Institute of Scientific and Technical Information of China (English)

    吴胜军; 夏振强

    2008-01-01

    In order to solve the seasonal supply problem of Clanis bilineata Walker larvae, effects of larva instar, time and temperature on larvae preserva-tion were studied in this experiment. The results indicated that the 5th instal" mature larvae had the best preservation durability, and their optimum preserva-tion condition was 2 -4℃ with a upper time limit of 8 months.

  16. Neuropsychological and Behavioural Phenotype of Dandy-Walker Variant Presenting in Chromosome 22 Trisomy: A Case Study

    Science.gov (United States)

    Searson, Ruth; Hare, Dougal Julian; Sridharan, Sridhar

    2013-01-01

    In this study, a case of Dandy-Walker variant syndrome associated with trisomy 22 in a 17-year-old man is described. This is the first account of this combination in a person surviving into adulthood, and the neuropsychological and behavioural presentation is described in detail and a clinical formulation is presented for the benefit of…

  17. "It's Not so Much a Job but a Relationship": A Response to Romer and Walker

    Science.gov (United States)

    O'Brien, John

    2013-01-01

    Romer and Walker's "Appreciative Inquiry," which obtained input from 16 capable personal assistants, challenges some influential assumptions about personal assistance and opens a way to think about the demanding work of developing capable and committed personal assistants. Attempts to depersonalize the relationship between people…

  18. Changes in Energy Cost and Total External Work of Muscles in Elite Race Walkers Walking at Different Speeds

    Directory of Open Access Journals (Sweden)

    Chwała Wiesław

    2014-12-01

    Full Text Available The aim of the study was to assess energy cost and total external work (total energy depending on the speed of race walking. Another objective was to determine the contribution of external work to total energy cost of walking at technical, threshold and racing speed in elite competitive race walkers.

  19. Review of the East Palaearctic and North Oriental Psyttalia Walker, with the description of three new species (Hymenoptera, Braconidae, Opiinae)

    NARCIS (Netherlands)

    Wu, Q.; Achterberg, van C.; Tan, J.-L.; Chen, X.-X.

    2016-01-01

    The East Palaearctic and North Oriental species of the genus Psyttalia Walker (Hymenoptera, Braconidae, Opiinae) are reviewed. Three new species are described and illustrated: P. latinervis Wu & van Achterberg, sp. n. and P. majocellata Wu & van Achterberg, sp. n. from China, and P. spectabilis van

  20. Nonlinear dynamics from the relativistic Boltzmann equation in the Friedmann-Lema\\^itre-Robertson-Walker spacetime

    CERN Document Server

    Bazow, D; Heinz, U; Martinez, M; Noronha, J

    2016-01-01

    The dissipative dynamics of an expanding massless gas with constant cross section in a spatially flat Friedmann-Lema\\^itre-Robertson-Walker (FLRW) universe is studied. The mathematical problem of solving the full nonlinear relativistic Boltzmann equation is recast into an infinite set of nonlinear ordinary differential equations for the moments of the one-particle distribution function. Momentum-space resolution is determined by the number of non-hydrodynamic modes included in the moment hierarchy, i.e., by the truncation order. We show that in the FLRW spacetime the non-hydrodynamic modes decouple completely from the hydrodynamic degrees of freedom. This results in the system flowing as an ideal fluid while at the same time producing entropy. The solutions to the nonlinear Boltzmann equation exhibit transient tails of the distribution function with nontrivial momentum dependence. The evolution of this tail is not correctly captured by the relaxation time approximation nor by the linearized Boltzmann equation...

  1. Improved gene prediction by principal component analysis based autoregressive Yule-Walker method.

    Science.gov (United States)

    Roy, Manidipa; Barman, Soma

    2016-01-10

    Spectral analysis using Fourier techniques is popular with gene prediction because of its simplicity. Model-based autoregressive (AR) spectral estimation gives better resolution even for small DNA segments but selection of appropriate model order is a critical issue. In this article a technique has been proposed where Yule-Walker autoregressive (YW-AR) process is combined with principal component analysis (PCA) for reduction in dimensionality. The spectral peaks of DNA signal are used to detect protein-coding regions based on the 1/3 frequency component. Here optimal model order selection is no more critical as noise is removed by PCA prior to power spectral density (PSD) estimation. Eigenvalue-ratio is used to find the threshold between signal and noise subspaces for data reduction. Superiority of proposed method over fast Fourier Transform (FFT) method and autoregressive method combined with wavelet packet transform (WPT) is established with the help of receiver operating characteristics (ROC) and discrimination measure (DM) respectively.

  2. Frequency domain analysis of power system transients using Welch and Yule-Walker AR methods

    Energy Technology Data Exchange (ETDEWEB)

    Alkan, Ahmet [Department of Computer Engineering, Yasar University, 35500 Izmir (Turkey); Yilmaz, Ahmet S. [Department of Electrical and Electronics Engineering, Kahramanmaras Suetcue Imam University, 46050-9 Kahramanmaras (Turkey)

    2007-07-15

    In this study, power quality (PQ) signals are analyzed by using Welch (non-parametric) and autoregressive (parametric) spectral estimation methods. The parameters of the autoregressive (AR) model were estimated by using the Yule-Walker method. PQ spectra were then used to compare the applied spectral estimation methods in terms of their frequency resolution and the effects in determination of spectral components. The variations in the shape of the obtained power spectra were examined in order to detect power system transients. Performance of the proposed methods was evaluated by means of power spectral densities (PSDs). Graphical results comparing the performance of the AR method with that of the Welch technique are given. The results demonstrate superior performance of the AR method over the Welch method. (author)

  3. Dynamic pedobarographic classification of idiopathic toe-walkers for therapeutical indication

    Directory of Open Access Journals (Sweden)

    Patricia Martín-Casas

    2017-03-01

    Full Text Available Idiopathic toe-walkers (ITWs pedobarographic analysis has not been described yet nor its possible relationship with orthopedical and developmental characteristics. The objective of this research is to develop a dynamic pedobarographic classification of ITWs to propose a specific therapeutical approach. Through an observational study, 56 ITWs aged 3-6 years were classified by their initial foot contact; differences between idiopatic toe-walking (ITW types and with respect to 40 control children were calculated by means of ANOVA and Student t-tests. The results show that the three ITW types displayed different step models for pressure and impulse distribution and also for temporal development (p less than .05. They also showed different orthopedic and developmental characteristics (p less than .05. As a whole, they demonstrated different severity levels, which suggest different therapeutical indications. This study confirms the convenience of a specific orthopedic, developmental, and gait assessment in ITW to clarify therapeutical indication.

  4. Morphological manifestations of the Dandy-Walker syndrom in female members of a family.

    Science.gov (United States)

    Titlić, Marina; Alfirević, Stanko; Kolić, Krešimir; Soldo, Anamarija; Tripalol, Ana Batoš

    2015-03-01

    The Dandy-Walker syndrome (DWS) is a hereditary disorder, appearing somewhat more frequently in women. The most important characteristics of the DWS are the lack of the cerebellar vermis, varying from a partial lack to a complete agenesis, and enlargement of the cerebrospinal spaces, especially in the fourth ventricle. The above mentioned morphological changes clinically manifest in ataxia, increased intracranial pressure and hydrocephalus. Here is presented a family with DWS, where the disease is contracted only by female members, in two generations, whereas no signs of DWS have been noticed in male family members. DWS is clinically manifested from early childhood to middle age, with the morphological changes varying from hypoplastic cerebellar vermis to widening of the brain ventricles and hydrocephalus and arachnoid cyst in the occipital part.

  5. Large scale dynamics of the Persistent Turning Walker model of fish behavior

    CERN Document Server

    Degond, Pierre

    2007-01-01

    This paper considers a new model of individual displacement, based on fish motion, the so-called Persistent Turning Walker (PTW) model, which involves an Ornstein-Uhlenbeck process on the curvature of the particle trajectory. The goal is to show that its large time and space scale dynamics is of diffusive type, and to provide an analytic expression of the diffusion coefficient. Two methods are investigated. In the first one, we compute the large time asymptotics of the variance of the individual stochastic trajectories. The second method is based on a diffusion approximation of the kinetic formulation of these stochastic trajectories. The kinetic model is a Fokker-Planck type equation posed in an extended phase-space involving the curvature among the kinetic variables. We show that both methods lead to the same value of the diffusion constant. We present some numerical simulations to illustrate the theoretical results.

  6. Growth by random walker sampling and scaling of the dielectric breakdown model

    Science.gov (United States)

    Somfai, Ellák; Goold, Nicholas R.; Ball, Robin C.; Devita, Jason P.; Sander, Leonard M.

    2004-11-01

    Random walkers absorbing on a boundary sample the harmonic measure linearly and independently: we discuss how the recurrence times between impacts enable nonlinear moments of the measure to be estimated. From this we derive a technique to simulate dielectric breakdown model growth, which is governed nonlinearly by the harmonic measure. For diffusion-limited aggregation, recurrence times are shown to be accurate and effective in probing the multifractal growth measure in its active region. For the dielectric breakdown model our technique grows large clusters efficiently and we are led to significantly revise earlier exponent estimates. Previous results by two conformal mapping techniques were less converged than expected, and in particular a recent theoretical suggestion of superuniversality is firmly refuted.

  7. Phase-plane analysis of Friedmann-Robertson-Walker cosmologies in Brans-Dicke gravity

    CERN Document Server

    Holden, D J; Holden, Damien J.; Wands, David

    1998-01-01

    We present an autonomous phase-plane describing the evolution of Friedmann-Robertson-Walker models containing a perfect fluid (with barotropic index gamma) in Brans-Dicke gravity (with Brans-Dicke parameter omega). We find self-similar fixed points corresponding to Nariai's power-law solutions for spatially flat models and curvature-scaling solutions for curved models. At infinite values of the phase-plane variables we recover O'Hanlon and Tupper's vacuum solutions for spatially flat models and the Milne universe for negative spatial curvature. We find conditions for the existence and stability of these critical points and describe the qualitative evolution in all regions of the (omega,gamma) parameter space for 0-3/2. We show that the condition for inflation in Brans-Dicke gravity is always stronger than the general relativistic condition, gamma<2/3.

  8. Clustering determines the survivor for competing Brownian and L\\'evy walkers

    CERN Document Server

    Heinsalu, Els; López, Cristóbal

    2013-01-01

    The competition between two ecologically similar species that use the same resources and differ from each other only in the type of spatial motion they undergo is studied. The latter is assumed to be described either by Brownian motion or L\\'evy flights. Competition is taken into account by assuming that individuals reproduce in a density-dependent fashion. It is observed that no influence of the type of motion occurs when the two species are in a well-mixed unstructured state. However, as soon as the species develop spatial clustering, the one forming more concentrated clusters gets a competitive advantage and eliminates the other. Similar competitive advantage would occur between walkers of the same type but with different diffusivities if this leads also to different clustering. Coexistence of both species is also possible under certain conditions.

  9. "It feels good to be measured": clinical role-play, Walker Percy, and the tingles.

    Science.gov (United States)

    Ahuja, Nitin K

    2013-01-01

    A large online community has recently formed around autonomous sensory meridian response (ASMR), a pleasant and poorly understood somatic reaction to specific interpersonal triggers. Its web-based manifestations include a variety of amateur videos designed to elicit the reaction, many of which feature protracted imitations of a clinician's physical exam. This analysis considers through a literary lens the proximity of this phenomenon to clinical diagnostics, focusing in particular on characterizations of spiritual isolation elaborated in Love in the Ruins (1971), the third novel by physician-writer Walker Percy (1916-1990). Within this speculative framework, the tendency to derive pleasure from clinical milieus, real or constructed, may be interpreted as a quality particular to the postmodern psyche. Viewing web-based clinical role-play in light of Percy's writing also underscores the possibility that routine diagnostic assessments may have independent therapeutic implications.

  10. Feasible domain of Walker's unsteady wall-layer model for the velocity profile in turbulent flows

    Directory of Open Access Journals (Sweden)

    MIKHAIL D. MIKHAILOV

    2014-12-01

    Full Text Available The present work studies, in detail, the unsteady wall-layer model of Walker et al. (1989, AIAA J., 27, 140 – 149 for the velocity profile in turbulent flows. Two new terms are included in the transcendental non-linear system of equations that is used to determine the three main model parameters. The mathematical and physical feasible domains of the model are determined as a function of the non-dimensional pressure gradient parameter (p+. An explicit parameterization is presented for the average period between bursts (, the origin of time ( and the integration constant of the time dependent equation (A0 in terms of p+. In the present procedure, all working systems of differential equations are transformed, resulting in a very fast computational procedure that can be used to develop real-time flow simulators.

  11. Feasible domain of Walker's unsteady wall-layer model for the velocity profile in turbulent flows.

    Science.gov (United States)

    Mikhailov, Mikhail D; Freire, Atila P Silva

    2014-12-01

    The present work studies, in detail, the unsteady wall-layer model of Walker et al. (1989, AIAA J., 27, 140 – 149) for the velocity profile in turbulent flows. Two new terms are included in the transcendental nonlinear system of equations that is used to determine the three main model parameters. The mathematical and physical feasible domains of the model are determined as a function of the non-dimensional pressure gradient parameter (p+). An explicit parameterization is presented for the average period between bursts (T+B), the origin of time (t+0 ) and the integration constant of the time dependent equation (A0) in terms of p+. In the present procedure, all working systems of differential equations are transformed, resulting in a very fast computational procedure that can be used to develop real-time flow simulators.

  12. A Kinematic Model for Vertical Axis Rotation within the Mina Deflection of the Walker Lane

    Science.gov (United States)

    Gledhill, T.; Pluhar, C. J.; Johnson, S. A.; Lindeman, J. R.; Petronis, M. S.

    2016-12-01

    The Mina Deflection, at the boundary between the Central and Southern Walker Lane, spans the California-Nevada border and includes a heavily-faulted Pliocene volcanic field overlying Miocene ignimbrites. The dextral Walker Lane accommodates 25% of relative Pacific-North America plate motion and steps right across the sinistral Mina deflection. Ours and previous work shows that the Mina Deflection partially accommodates deformation by vertical-axis rotation of up to 99.9o ± 6.1o rotation since 11 Ma. This rotation is evident in latite ignimbrite of Gilbert et al. (1971), which we have formalized as three members of Tuff of Huntoon Creek (THC). The welded, basal, normal-polarity Huntoon Valley Member of THC is overlain by the unwelded to partially-welded, reversed-polarity Adobe Hills Mbr. This member includes internal breaks suggesting multiple eruptive phases, but the paleomagnetic results from each are statistically indistinguishable, meaning that they were likely erupted in rapid succession (within a few centuries of one another). THC ends with a welded member exhibiting very shallow inclination and south declination that we call Excursional Mbr. One of the upper members has been dated at 11.17 ± 0.04 Ma. These Miocene units are overlain by Pliocene basalts, Quaternary alluvium, and lacustrine deposits. Our paleomagnetic results show a gradient between the zero rotation domain and high rotation across a 20km baseline. A micropolar model, based on 25 years of earthquake data from the Northern and Southern California Seismic Network, suggest the Mina Deflection is currently experiencing transpressional seismogenic deformation (Unruh et al., 2003). Accepting Unruh's model and assuming continuous rotation since 11 Ma, we propose a kinematic model for the western Mina Deflection that accommodates 90o of vertical axis rotation from N-S to ENE-WSW oriented blocks.

  13. The utility of the Digi-walker step counter to assess daily physical activity patterns.

    Science.gov (United States)

    Welk, G J; Differding, J A; Thompson, R W; Blair, S N; Dziura, J; Hart, P

    2000-09-01

    The Digi-Walker step counter is a promising and cost-effective tool to measure physical activity under free-living conditions. Two specific studies were conducted to evaluate the number of steps required to meet current physical activity guidelines. Thirty-one adults (17 men, 14 women) served as participants. In study 1, we determined the number of steps to complete a mile under two different conditions and three paces. In study 2, we conducted a field trial to examine the relationship between daily step counts and other indices of physical activity. Participants in this study wore a Digi-Walker for 2 consecutive weeks and completed the 7-d physical activity recall (PAR) after each week. In study 1, there were no differences in step counts by site, but steps were inversely related to pace, with values ranging from 1330 to 1996. Individual step counts at a specific pace were negatively correlated with height, weight, leg length, and stride length and were positively correlated with body fatness. In study 2, participants had average daily step counts of 11,603 when structured vigorous activity was included and 8265 when only light and moderate activity were measured. Modest correlations were found between step counts and estimated energy expenditure. Similar correlations were observed when step counts were related to minutes of activity per day and minutes of sitting per day. Pedometers provide a useful indicator of daily step counts but variability in activity patterns make it difficult to establish step count guidelines that correspond with other public health guidelines.

  14. Walker-A Motif Acts to Coordinate ATP Hydrolysis with Motor Output in Viral DNA Packaging.

    Science.gov (United States)

    delToro, Damian; Ortiz, David; Ordyan, Mariam; Sippy, Jean; Oh, Choon-Seok; Keller, Nicholas; Feiss, Michael; Catalano, Carlos E; Smith, Douglas E

    2016-07-03

    During the assembly of many viruses, a powerful ATP-driven motor translocates DNA into a preformed procapsid. A Walker-A "P-loop" motif is proposed to coordinate ATP binding and hydrolysis with DNA translocation. We use genetic, biochemical, and biophysical techniques to survey the roles of P-loop residues in bacteriophage lambda motor function. We identify 55 point mutations that reduce virus yield to below detectable levels in a highly sensitive genetic complementation assay and 33 that cause varying reductions in yield. Most changes in the predicted conserved residues K76, R79, G81, and S83 produce no detectable yield. Biochemical analyses show that R79A and S83A mutant proteins fold, assemble, and display genome maturation activity similar to wild-type (WT) but exhibit little ATPase or DNA packaging activity. Kinetic DNA cleavage and ATPase measurements implicate R79 in motor ring assembly on DNA, supporting recent structural models that locate the P-loop at the interface between motor subunits. Single-molecule measurements detect no translocation for K76A and K76R, while G81A and S83A exhibit strong impairments, consistent with their predicted roles in ATP binding. We identify eight residue changes spanning A78-K84 that yield impaired translocation phenotypes and show that Walker-A residues play important roles in determining motor velocity, pausing, and processivity. The efficiency of initiation of packaging correlates strongly with motor velocity. Frequent pausing and slipping caused by changes A78V and R79K suggest that these residues are important for ATP alignment and coupling of ATP binding to DNA gripping. Our findings support recent structural models implicating the P-loop arginine in ATP hydrolysis and mechanochemical coupling.

  15. EFFECTS OF HYDROGEOMORPHIC REGION, WATERSHED STORAGE, AND FOREST FRAGMENTATION ON WATERSHED EXPORTS

    Science.gov (United States)

    Turbidity was highest for South Shore streams overall, but exhibited a significant HGM x storage x fragmentation effect, with highest levels observed in South Shore low storage/high fragmentation watersheds.

  16. The Effect and Benefit of Rice Chilo suppressalis Walker Chemical Control Test of Chlorantrani-liprole etc.

    Institute of Scientific and Technical Information of China (English)

    Changjia PENG; Pan DING; Tikun BAI; Libin FENG; Huaizhong YIN; Wanqiu WANG; Zhongyu FU

    2015-01-01

    In this paper, the first generation and second generation of Chilo sup-pressalis Walker were conducted as the test objects to investigate control of a new pesticide (chlorantraniliprole) with preparation of chlorantraniliprole 20% SC, abamectin 1.8% EC and chlorpyrifos 40% EC to Chilo suppressalis Walker. The re-sults showed that chlorantraniliprole 20% SC, abamectin 1.8% EC and chlorpyrifos 40% EC had effective control to Chilo suppressalis Walker for its excel ent control efficacy and long persistence period. Seedling protection efficacies were between 84.2%-100%, 90.1% and 92.1%, and insecticidal efficacies were between 84.6%-100%, 90.7% and 93.8% 36 days after application of chlorantraniliprole 20% SC in treat-ments with abamectin 1.8% EC and chlorpyrifos 40% EC for first generation Chilo suppressalis Walker control. The dead panicles were between 0.2%-1.4%, 0.8%and 0.7%, pest plant rate control in 0.4%-2.2%, 1.1% and 0.9%, and the rates of damaged rice plants were between 82.4%-97.6%, 90.2%-91.2% and 91.4%-92.8%, 30 days after application of chlorantraniliprole 20% SC, abamectin 1.8% EC and chlorpyrifos 40% EC for the second generation Chilo suppressalis Walker control. It can effectively protect seedlings, protect spike, increase grain number and grain weight, which promoting the increase production income effect. The real estate in-creased by 9.7%-12.3%, 10.9% and 11.2% than water treatment (CK) with a very significant level, while the incomes were higher than 1 719.19-1 998.22, 1 956.52 and 2 057.83 yuan.

  17. “Ancestors We Didn’t Even Know We Had”: Alice Walker, Asian Religion, and Ethnic Authenticity

    Directory of Open Access Journals (Sweden)

    Kyle Garton-Gundling

    2015-03-01

    Full Text Available Recent debates about the ethics of identity in a global age have dealt with how to prioritize conflicting local and global allegiances. Guided by these concerns, the fiction of Alice Walker develops a distinctive view of how local cultures and global movements can fruitfully interact. This vision depends on concepts from Asian religions, a major influence that critics of Walker have largely overlooked. Walker promotes Hindu and Buddhist meditation in a context of widespread African American skepticism toward Asian religions. According to widespread notions of cultural authenticity, Asian religions cannot nourish an African American connection to ethnic roots. In response to this challenge, Alice Walker’s fiction portrays Hindu and Buddhist mystics as African Americans’ ancestors, thus positioning these faiths as authentically black. By creatively enfolding Asian religions into her sense of African American heritage, Walker builds a spiritual cosmopolitanism that relies on claims of ancestral affiliation even when these claims are not literal. This strategy is Walker’s effort to create a new paradigm of cultural authenticity, one that allows individuals and groups to choose their ancestors. Walker’s approach seeks to incorporate disparate global influences while still valorizing the figure of the ancestor. This innovative approach places Walker at the forefront of a growing number of African American artists and intellectuals who promote Asian religions to American minorities. Walker’s work vividly dramatizes larger concerns in transnational American Studies: Eastern philosophy’s relevance to identity politics, the tensions between universal ideals and cultural specifics, and the ethics of cross-cultural appropriation.

  18. Participation of the NO/cGMP/K+ATP pathway in the antinociception induced by Walker tumor bearing in rats

    Directory of Open Access Journals (Sweden)

    A.L.R. Barbosa

    2012-06-01

    Full Text Available Implantation of Walker 256 tumor decreases acute systemic inflammation in rats. Inflammatory hyperalgesia is one of the most important events of acute inflammation. The L-arginine/NO/cGMP/K+ATP pathway has been proposed as the mechanism of peripheral antinociception mediated by several drugs and physical exercise. The objective of this study was to investigate a possible involvement of the NO/cGMP/K+ATP pathway in antinociception induced in Walker 256 tumor-bearing male Wistar rats (180-220 g. The groups consisted of 5-6 animals. Mechanical inflammatory hypernociception was evaluated using an electronic version of the von Frey test. Walker tumor (4th and 7th day post-implantation reduced prostaglandin E2- (PGE2, 400 ng/paw; 50 µL; intraplantar injection and carrageenan-induced hypernociception (500 µg/paw; 100 µL; intraplantar injection. Walker tumor-induced analgesia was reversed (99.3% for carrageenan and 77.2% for PGE2 by a selective inhibitor of nitric oxide synthase (L-NAME; 90 mg/kg, ip and L-arginine (200 mg/kg, ip, which prevented (80% for carrageenan and 65% for PGE2 the effect of L-NAME. Treatment with the soluble guanylyl cyclase inhibitor ODQ (100% for carrageenan and 95% for PGE2; 8 µg/paw and the ATP-sensitive K+ channel (KATP blocker glibenclamide (87.5% for carrageenan and 100% for PGE2; 160 µg/paw reversed the antinociceptive effect of tumor bearing in a statistically significant manner (P < 0.05. The present study confirmed an intrinsic peripheral antinociceptive effect of Walker tumor bearing in rats. This antinociceptive effect seemed to be mediated by activation of the NO/cGMP pathway followed by the opening of KATP channels.

  19. Boosted Regression Tree Models to Explain Watershed ...

    Science.gov (United States)

    Boosted regression tree (BRT) models were developed to quantify the nonlinear relationships between landscape variables and nutrient concentrations in a mesoscale mixed land cover watershed during base-flow conditions. Factors that affect instream biological components, based on the Index of Biotic Integrity (IBI), were also analyzed. Seasonal BRT models at two spatial scales (watershed and riparian buffered area [RBA]) for nitrite-nitrate (NO2-NO3), total Kjeldahl nitrogen, and total phosphorus (TP) and annual models for the IBI score were developed. Two primary factors — location within the watershed (i.e., geographic position, stream order, and distance to a downstream confluence) and percentage of urban land cover (both scales) — emerged as important predictor variables. Latitude and longitude interacted with other factors to explain the variability in summer NO2-NO3 concentrations and IBI scores. BRT results also suggested that location might be associated with indicators of sources (e.g., land cover), runoff potential (e.g., soil and topographic factors), and processes not easily represented by spatial data indicators. Runoff indicators (e.g., Hydrological Soil Group D and Topographic Wetness Indices) explained a substantial portion of the variability in nutrient concentrations as did point sources for TP in the summer months. The results from our BRT approach can help prioritize areas for nutrient management in mixed-use and heavily impacted watershed

  20. Recovery of central Appalachian forested watershed

    Science.gov (United States)

    Mary Beth Adams; James N. Kochendenfer [sic

    2014-01-01

    The Fernow Experimental Forest (FEF) was established to conduct research in forest and watershed management in the central Appalachians. The 1868-ha FEF, located south of Parsons, West Virginia, is administered by the Northern Research Station of the USDA Forest Service and provides a valuable point of comparison with the Coweeta Hydrologic Laboratory (CHL), located in...

  1. The Implementation of a Parallel Watershed Algorithm

    NARCIS (Netherlands)

    Meijster, A.; Roerdink, J.B.T.M.

    1995-01-01

    In this paper the implementation of a parallel watershed algorithm is described. The algorithm is implemented on a multiple instruction multiple data (MIMD) ring-architecture using a single program multiple data (SPMD) approach using an asynchronous message passing interface and simulated shared mem

  2. Modeling global nutrient export from watersheds

    NARCIS (Netherlands)

    Kroeze, C.; Bouwman, L.; Seitzinger, S.

    2012-01-01

    We describe how global models can be used to analyze past and future trends in nutrient export from watersheds and how such models can be used to analyze causes and effects of coastal eutrophication. Future nutrient inputs to coastal waters may be higher than today, and nutrient ratios may depart fr

  3. A mean field approach to watershed hydrology

    Science.gov (United States)

    Bartlett, Mark; Porporato, Amilcare

    2016-04-01

    Mean field theory (also known as self-consistent field theory) is commonly used in statistical physics when modeling the space-time behavior of complex systems. The mean field theory approximates a complex multi-component system by considering a lumped (or average) effect for all individual components acting on a single component. Thus, the many body problem is reduced to a one body problem. For watershed hydrology, a mean field theory reduces the numerous point component effects to more tractable watershed averages, resulting in a consistent method for linking the average watershed fluxes to the local fluxes at each point. We apply this approach to the spatial distribution of soil moisture, and as a result, the numerous local interactions related to lateral fluxes of soil water are parameterized in terms of the average soil moisture. The mean field approach provides a basis for unifying and extending common event-based models (e.g. Soil Conservation Service curve number (SCS-CN) method) with more modern semi-distributed models (e.g. Variable Infiltration Capacity (VIC) model, the Probability Distributed (PDM) model, and TOPMODEL). We obtain simple equations for the fractions of the different source areas of runoff, the spatial variability of runoff, and the average runoff value (i.e., the so-called runoff curve). The resulting space time distribution of soil moisture offers a concise description of the variability of watershed fluxes.

  4. 36 CFR 251.35 - Petersburg watershed.

    Science.gov (United States)

    2010-07-01

    ... Federal employees, holders of Forest Service contracts, or Forest Service agents; (2) The operation, maintenance, and improvement of the municipal water system by Federal and State officials and employees of the... Ranger. (d) Unauthorized entrance upon lands within the watershed is subject to punishment as provided...

  5. Protect and Restore Lolo Creek Watershed : Annual Report CY 2005.

    Energy Technology Data Exchange (ETDEWEB)

    McRoberts, Heidi

    2006-03-01

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. Watershed restoration projects within the Lolo Creek watershed are coordinated with the Clearwater National Forest and Potlatch Corporation. The Nez Perce Tribe began watershed restoration projects within the Lolo Creek watershed of the Clearwater River in 1996. Fencing to exclude cattle for stream banks, stream bank stabilization, decommissioning roads, and upgrading culverts are the primary focuses of this effort. The successful completion of the replacement and removal of several passage blocking culverts represent a major improvement to the watershed. These projects, coupled with other recently completed projects and those anticipated in the future, are a significant step in improving habitat conditions in Lolo Creek.

  6. Mechanisms of side branching and tip splitting in a model of branching morphogenesis.

    Directory of Open Access Journals (Sweden)

    Yina Guo

    Full Text Available Recent experimental work in lung morphogenesis has described an elegant pattern of branching phenomena. Two primary forms of branching have been identified: side branching and tip splitting. In our previous study of lung branching morphogenesis, we used a 4 variable partial differential equation (PDE, due to Meinhardt, as our mathematical model to describe the reaction and diffusion of morphogens creating those branched patterns. By altering key parameters in the model, we were able to reproduce all the branching styles and the switch between branching modes. Here, we attempt to explain the branching phenomena described above, as growing out of two fundamental instabilities, one in the longitudinal (growth direction and the other in the transverse direction. We begin by decoupling the original branching process into two semi-independent sub-processes, 1 a classic activator/inhibitor system along the growing stalk, and 2 the spatial growth of the stalk. We then reduced the full branching model into an activator/inhibitor model that embeds growth of the stalk as a controllable parameter, to explore the mechanisms that determine different branching patterns. We found that, in this model, 1 side branching results from a pattern-formation instability of the activator/inhibitor subsystem in the longitudinal direction. This instability is far from equilibrium, requiring a large inhomogeneity in the initial conditions. It successively creates periodic activator peaks along the growing stalk, each of which later on migrates out and forms a side branch; 2 tip splitting is due to a Turing-style instability along the transversal direction, that creates the spatial splitting of the activator peak into 2 simultaneously-formed peaks at the growing tip, the occurrence of which requires the widening of the growing stalk. Tip splitting is abolished when transversal stalk widening is prevented; 3 when both instabilities are satisfied, tip bifurcation occurs

  7. Measurement of Prominent eta Decay Branching Fractions

    CERN Document Server

    López, A; Méndez, H; Ramírez, J; Ge, J Y; Miller, D H; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Naik, P; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Ernst, J; Ecklund, K M; Severini, H; Love, W; Savinov, V

    2007-01-01

    The decay psi(2S) --> eta J/psi is used to measure, for the first time, all prominent eta-meson branching fractions with the same experiment in the same dataset, thereby providing a consistent treatment of systematics across branching fractions. We present results for eta decays to gamma gamma, pi+pi-pi0, 3 pi0, pi+ pi- gamma, and e+ e- gamma, accounting for 99.9% of all eta decays. The precisions for several of the branching fractions and their ratios are improved. Two channels, pi+ pi- gamma and e+ e- gamma, show results that differ at the level of three standard deviations from those previously determined.

  8. Agents in branching space-times

    Institute of Scientific and Technical Information of China (English)

    Nuel; Belnap

    2003-01-01

    The aim of this essay Is to make some brief suggestions on the beginnings of a theory of agentsand agency In branching spacetlmes.foe thought Is to combine the ideas of agency as developed agalnst the relatively simple background of branching time with the richer notions of Indetermlnlsm asstructured In the theory of branching space-times.My plan Is to say a little about agency In branchingtime and a little about branchlg spacetlmes,and then ask how the two can be brought together.Atthe end there Is an ...

  9. Cellular and physical mechanisms of branching morphogenesis

    Science.gov (United States)

    Varner, Victor D.; Nelson, Celeste M.

    2014-01-01

    Branching morphogenesis is the developmental program that builds the ramified epithelial trees of various organs, including the airways of the lung, the collecting ducts of the kidney, and the ducts of the mammary and salivary glands. Even though the final geometries of epithelial trees are distinct, the molecular signaling pathways that control branching morphogenesis appear to be conserved across organs and species. However, despite this molecular homology, recent advances in cell lineage analysis and real-time imaging have uncovered surprising differences in the mechanisms that build these diverse tissues. Here, we review these studies and discuss the cellular and physical mechanisms that can contribute to branching morphogenesis. PMID:25005470

  10. Tillering and panicle branching genes in rice.

    Science.gov (United States)

    Liang, Wei-hong; Shang, Fei; Lin, Qun-ting; Lou, Chen; Zhang, Jing

    2014-03-01

    Rice (Oryza sativa L.) is one of the most important staple food crops in the world, and rice tillering and panicle branching are important traits determining grain yield. Since the gene MONOCULM 1 (MOC 1) was first characterized as a key regulator in controlling rice tillering and branching, great progress has been achieved in identifying important genes associated with grain yield, elucidating the genetic basis of yield-related traits. Some of these important genes were shown to be applicable for molecular breeding of high-yielding rice. This review focuses on recent advances, with emphasis on rice tillering and panicle branching genes, and their regulatory networks.

  11. The return branch of viscous fingers

    CERN Document Server

    Vera, F

    2005-01-01

    We report a simple experiment of two-dimensional pattern formation in a circular Hele-Shaw cell, showing the appearance of a return branch that is equivalent to the upward-connecting leader of lightning. Injecting water from the center into a foam filled cell, we obtained patterns similar to dendrites of two-dimensional dielectric breakdown experiments. When we repeat this experiment allowing the presence of water in the outer (low pressure) region, dendrites grow initially as in a normal experiment, but when a branch is near the outer boundary, the low pressure water begins to penetrate the foam against the pressure field, forming several return branches.

  12. Integrated Resource Management at a Watershed Scale

    Science.gov (United States)

    Byrne, J. M.; MacDonald, R. J.; Cairns, D.; Barnes, C. C.; Mirmasoudi, S. S.; Lewis, D.

    2014-12-01

    Watershed hydrologists, managers and planners have a long list of resources to "manage." Our group has worked for over a decade to develop and apply the GENESYS (Generate Earth Systems Science) high-resolution spatial hydrometeorological model. GENESYS was intended for modelling of alpine snowpack, and that work has been the subject of a series of hydrometeorology papers that applied the model to evaluate how climate change may impact water resources for a series of climate warming scenarios through 2100. GENESYS has research modules that have been used to assess alpine glacier mass balance, soil water and drought, forest fire risk under climate change, and a series of papers linking GENESYS to a water temperature model for small headwater streams. Through a major commercialization grant, we are refining, building, adopting, and adapting routines for flood hydrology and hydraulics, surface and groundwater storage and runoff, crop and ecosystem soil water budgets, and biomass yields. The model will be available for research collaborations in the near future. The central goal of this development program is to provide a series of research and development tools for non-profit integrated resource management in the developed and developing world. A broader question that arises is what are the bounds of watershed management, if any? How long should our list of "managed" resources be? Parallel work is evaluating the relative values of watershed specialists managing many more resources with the watershed. Hydroelectric power is often a key resource complimentary to wind, solar and biomass renewable energy developments; and biomass energy is linked to water supply and agriculture. The August 2014 massive tailings dam failure in British Columbia threatens extensive portions of the Fraser River sockeye salmon run, millions of fish, and there are concerns about long-term contamination of water supplies for many British Columbians. This disaster, and many others that may occur

  13. URBAN WATERSHED STUDIES IN SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Cristiano Poleto

    2007-12-01

    Full Text Available One of the greatest problems observed in Brazilian urban watersheds are concerned to the amount of solid residues, domestic sewerage and sediments that are disposed in the rivers and streams that drain those areas. This project aims to present these problems through a study of case taken in an urban watershed in Porto Alegre city, Southern Brazil. For this study, different procedures were used, such as field surveys, interviews with the inhabitants, satellite images, sediment samples, flow measures and morphology assessment of part of the local fluvial system to check the degree of instability of the channel. In 2005, it was verified that 42.57% of the watershed was impermeable, considering the paved streets, the residential and commercial buildings and stone pavements. As there was no sewer treatment, most of this sewerage was directly disposed into the stream and the TOC has reached 20% (m/m. Moreover, the occupation of riparian areas, a great amount of soil exposed in the watershed, the nonpaved streets and a great volume of solid residues were causing the instability in the channel, silting the stream bed. The metals (Zn, Pb and Cr selected for this study are most frequently found in high concentrations in urban areas. The results suggest the occurrence of a high enrichment of the fluvial sediment by these metals. The concentrations of these elements vary temporally during storms due to the input of impervious area runoff containing high concentration of elements associated to vehicular traffic and other anthropogenic activities. Then, it is possible to conclude that the contamination of the urban watershed is reflected in the results obtained in the fluvial suspended sediments.

  14. URBAN WATERSHED STUDIES IN SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Cristiano Poleto

    2007-01-01

    Full Text Available One of the greatest problems observed in Brazilian urban watersheds are concerned to the amount of solid residues, domestic sewerage and sediments that are disposed in the rivers and streams that drain those areas. This project aims to present these problems through a study of case taken in an urban watershed in Porto Alegre city, Southern Brazil. For this study, different procedures were used, such as field surveys, interviews with the inhabitants, satellite images, sediment samples, flow measures and morphology assessment of part of the local fluvial system to check the degree of instability of the channel. In 2005, it was verified that 42.57% of the watershed was impermeable, considering the paved streets, the residential and commercial buildings and stone pavements. As there was no sewer treatment, most of this sewerage was directly disposed into the stream and the TOC has reached 20% (m/m. Moreover, the occupation of riparian areas, a great amount of soil exposed in the watershed, the nonpaved streets and a great volume of solid residues were causing the instability in the channel, silting the stream bed. The metals (Zn, Pb and Cr selected for this study are most frequently found in high concentrations in urban areas. The results suggest the occurrence of a high enrichment of the fluvial sediment by these metals. The concentrations of these elements vary temporally during storms due to the input of impervious area runoff containing high concentration of elements associated to vehicular traffic and other anthropogenic activities. Then, it is possible to conclude that the contamination of the urban watershed is reflected in the results obtained in the fluvial suspended sediments.

  15. Overview of the Advanced High Frequency Branch

    Science.gov (United States)

    Miranda, Felix A.

    2015-01-01

    This presentation provides an overview of the competencies, selected areas of research and technology development activities, and current external collaborative efforts of the NASA Glenn Research Center's Advanced High Frequency Branch.

  16. Human Dimensions Branch 2016 Annual Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual report provides an overview of the work that the Human Dimensions Branch completed in FY2016, including a peak at: Monarch butterfly conservation and how...

  17. Residence times of branching diffusion processes

    Science.gov (United States)

    Dumonteil, E.; Mazzolo, A.

    2016-07-01

    The residence time of a branching Brownian process is the amount of time that the mother particle and all its descendants spend inside a domain. Using the Feynman-Kac formalism, we derive the residence-time equation as well as the equations for its moments for a branching diffusion process with an arbitrary number of descendants. This general approach is illustrated with simple examples in free space and in confined geometries where explicit formulas for the moments are obtained within the long time limit. In particular, we study in detail the influence of the branching mechanism on those moments. The present approach can also be applied to investigate other additive functionals of branching Brownian process.

  18. FY 1990 Applied Sciences Branch annual report

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, B.M.; Dippo, P.C. (eds.)

    1991-11-01

    The Applied Sciences Branch actively supports the advancement of DOE/SERI goals for the development and implementation of the solar photovoltaic technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility which is capable of providing information on the full range of photovoltaic components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of photovoltaic technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. This report contains information on surface and interface analysis, materials characterization, development, electro-optical characterization module testing and performance, surface interactions and FTIR spectroscopy.

  19. Damping by branching: a bioinspiration from trees

    CERN Document Server

    Theckes, Benoit; Boutillon, Xavier

    2011-01-01

    Man-made slender structures are known to be sensitive to high levels of vibration, due to their flexibility, which often cause irreversible damage. In nature, trees repeatedly endure large amplitudes of motion, mostly caused by strong climatic events, yet with minor or no damage in most cases. A new damping mechanism inspired by the architecture of trees is here identified and characterized in the simplest tree-like structure, a Y-shape branched structure. Through analytical and numerical analyses of a simple two-degree-of-freedom model, branching is shown to be the key ingredient in this protective mechanism that we call damping-by-branching. It originates in the geometrical nonlinearities so that it is specifically efficient to damp out large amplitudes of motion. A more realistic model, using flexible beam approximation, shows that the mechanism is robust. Finally, two bioinspired architectures are analyzed, showing significant levels of damping achieved via branching with typically 30% of the energy being...

  20. Arkansas State University Beebe Branch Faculty Handbook.

    Science.gov (United States)

    Arkansas State Univ., Beebe.

    Arkansas State University Beebe Branch provides a liberal arts oriented program for traditional and nontraditional students. Its faculty handbook contains institutional goals, description of responsibilities of administrative officers and faculty committees, faculty employment policies, and administrative and instructional policies. The…

  1. Surgical repair of pulmonary artery branches.

    Science.gov (United States)

    Ghez, Olivier; Saeed, Imran; Serrato, Maria; Quintero, Diana Bernal; Kreitmann, Bernard; Fraisse, Alain; Uemura, Hideki; Seale, Anna; Daubeney, Piers; McCarthy, Karen; Ho, S Yen

    2013-01-01

    Surgical repair of pulmonary artery (PA) branches encompasses many different clinical scenarios and technical challenges. The most common, such as bifurcation and central PA reconstruction, are described, as well as the challenges of complex and peripheral reconstruction.

  2. The Novel Y-Branch With Two Reflectors

    Institute of Scientific and Technical Information of China (English)

    Ruei-Chang Lu; Yu-Pin Liao

    2003-01-01

    A novel Y-branch waveguide with two reflectors is proposed. The normalized transmitted power for the branching angle of 50°is greater than 70%, which is higher than conventional Y-branch with such wide angle.

  3. Perivascular exudates in frosted branch angiitis.

    Science.gov (United States)

    He, Lingmin; Moshfeghi, Darius M; Wong, Ira G

    2014-01-01

    Three cases of young, minimally symptomatic patients found to have vitritis and extensive perivenous vitreous exudates resembling frosted branch angiitis are presented. Optical coherence tomography showed that these exudates appear to be extravascated from the vasculature. The material persisted over 1 year on immunosuppressive therapy, suggesting that its resolution should not be a treatment end point. These cases add to our understanding of the spectrum of clinical findings in frosted branch angiitis.

  4. Branch retinal artery occlusion in Susac's syndrome

    Directory of Open Access Journals (Sweden)

    Ricardo Evangelista Marrocos de Aragão

    2015-02-01

    Full Text Available Susac's syndrome is a rare disease attribuited to a microangiopathy involving the arterioles of the cochlea, retina and brain. Encefalopathy, hearing loss, and visual deficits are the hallmarks of the disease. Visual loss is due to multiple, recurrent branch arterial retinal occlusions. We report a case of a 20-year-old women with Susac syndrome presented with peripheral vestibular syndrome, hearing loss, ataxia, vertigo, and vision loss due occlusion of the retinal branch artery.

  5. CAST Xi'an Branch Established

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ China Academy of Space Technology (CAST) Xi'an Branch was established on April 8,2008.The new branch consists of the headquarters of the former Xi'an Institute of Space Radio Technology (XISRT) of CAST and five former subsidiaries of the XISRT,i.e.the Institute of Space Electronic Technology,the Institute of Microwave Technology,the Institute of Space Antenna Technology,the Manufacturing Center for Space Electronics and Civilian High-tech Company.

  6. $\\tau$ hadronic branching ratios at DELPHI

    CERN Document Server

    Humble, Stephen

    1999-01-01

    Using data collected in the DELPHI detector at LEP1, we have measured the exclusive branching ratios in modes with several hadrons. Both classical cuts and neural network methods have been performed to make the best use of the DELPHI neutral particle identification capability. In addition, a measurement of inclusive branching ratios for tau decays containing one or three charged particles has been performed. (4 refs).

  7. Parton Branching in Color Mutation Model

    CERN Document Server

    Hwa, R C

    1999-01-01

    The soft production problem in hadronic collisions as described in the eikonal color mutation branching model is improved in the way that the initial parton distribution is treated. Furry branching of the partons is considered as a means of describing the nonperturbative process of parton reproduction in soft interaction. The values of all the moments, and $C_q$, for q=2,...,5, as well as their energy dependences can be correctly determined by the use of only two parameters.

  8. Diagnostic Systems Approach to Watershed Management

    Energy Technology Data Exchange (ETDEWEB)

    Davisson, M L

    2001-02-23

    The water quality of discharge from the surface water system is ultimately dictated by land use and climate within the watershed. Water quality has vastly improved from point source reduction measures, yet, non-point source pollutants continue to rise. 30 to 40% of rivers still do not meet water quality standards for reasons that include impact from urban storm water runoff, agricultural and livestock runoff, and loss of wetlands. Regulating non-point source pollutants proves to be difficult since specific dischargers are difficult to identify. However, parameters such as dissolved organic carbon (DOC) limit the amounts of chlorination due to simultaneous disinfection by-product formation. The concept of watershed management has gained much ground over the years as a means to resolve non-point source problems. Under this management scheme stakeholders in a watershed collectively agree to the nature and extent of non-point sources, determine water quality causes using sound scientific approaches, and together develop and implement a corrective plan. However, the ''science'' of watershed management currently has several shortcomings according to a recent National Research Council report. The scientific component of watershed management depends on acquiring knowledge that links water quality sources with geographic regions. However, there is an observational gap in this knowledge. In particular, almost all the water quality data that exists at a utility are of high frequency collected at a single point over a long period of time. Water quality data for utility purposes are rarely collected over an entire watershed. The potential is high, however, for various utilities in a single watershed to share and integrate water quality data, but no regulatory incentives exist at this point. The only other available water quality data originate from special scientific studies. Unfortunately these data rarely have long-term records and are usually tailored to

  9. Streamflow simulation by a watershed model using stochastically generated weather in New York City watersheds

    Science.gov (United States)

    Mukundan, R.; Acharya, N.; Gelda, R.; Owens, E. M.; Frei, A.; Schneiderman, E. M.

    2016-12-01

    Recent studies have reported increasing trends in total precipitation, and in the frequency and magnitude of extreme precipitation events in the West of Hudson (WOH) watersheds of the New York City (NYC) water supply. The potential effects of these changes may pose challenges for both water quality (such as increased sediment and nutrient loading) and quantity (such as reservoir storage and management). The NYC Dept. of Environmental Protection Climate Change Integrated Modeling Project (CCIMP) is using "bottom-up" or vulnerability based methods to explore climate impacts on water resources. Stochastic weather generators (SWGs) are an integral component of the bottom-up approach. Previous work has identified and evaluated the skill of alternative stochastic weather generators of varying complexity for simulating the statistical characteristics of observed minimum and maximum daily air temperature and occurrence and amount of precipitation. This evaluation focused on the skill in representing extreme streamflow event probabilities across NYC West of Hudson (WOH) watersheds. Synthetic weather time series from the selected (skewed normal) SWG were used to drive the Generalized Watershed Loading Function (GWLF) watershed model for a 600 year long period to simulate daily streamflows for WOH watersheds under a wide range of hydrologic conditions. Long-term average daily streamflows generated using the synthetic weather time series were comparable to values generated using observed long-term (1950-2009) weather time series. This study demonstrates the ability of the selected weather generator to adequately represent the hydrologic response in WOH watersheds with respect to the total, peak, and seasonality in streamflows. Future application of SWGs in NYC watersheds will include generating multiple scenarios of changing climate to evaluate water supply system vulnerability and selection of appropriate adaptation measures.

  10. Social Exclusion in Watershed Development: Evidence From the Indo-German Watershed Development Project in Maharashtra

    Directory of Open Access Journals (Sweden)

    Eshwer Kale

    2011-09-01

    Full Text Available The concept of social exclusion is context-specific and there is no uniform paradigm of exclusion across the world. This paper attempts to analyse exclusion of resource-poor groups in watershed development programmes in the Indian context. It aims to explore excluded community groups from the perspective of people’s equal opportunity and equal access to newly generated economic benefits in watershed development programmes. The paper also traces the determinant factors responsible for denial and exclusion of resource-poor groups and describes the detailed processes involved in their exclusion from institutional and livelihood opportunities in watershed programmes. At the same time, the paper also explores suggestions and views of resource-poor groups about their meaningful social inclusion in watershed programme. The Gadiwat Indo-German Watershed Development Project in Aurangabad district in the State of Maharashtra is studied in detail in terms of its social, economic and political realities through mix-method and multi-stakeholder approaches. The key findings of the paper are that landownership, caste, gender, membership in village institutions and/or watershed institutions or close relationship with members, as well as the limitations of the programme guidelines, are the major determinants of institutional inclusion and the extent of resulting economic benefits. The exclusion of resource-poor groups mainly takes the form of their exclusion from institutional representation. In order to promote meaningful social inclusion of resource-poor groups, there is need for a more livelihood-oriented focus and their equal representation and participation in watershed institutions.

  11. All change at the CERN UBS branch

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    UBS branches across the country are being modernised, and the CERN branch is no exception. The Bulletin brings you a preview of the project, which will get under way in January 2013.   Mock-up of the renovated UBS branch. The changes at the UBS branch in CERN's Main Building will be no simple facelift. The entire bank will be renovated, transforming the present relatively confined premises into an open and attractive area. "The renovation of the UBS branches is part of a wider campaign designed to further enhance our customer relations," explains Ezio Mangia, the head of the CERN branch.  The UBS bank currently occupies three sets of premises in CERN's Main Building (two on the ground floor and one in the basement). "By the end of the work, which is scheduled to be completed by the middle of next year, CERN customers will benefit from a new area with open-plan counters and "hole-in-the-wall" machines accessible to...

  12. Terminal Branch of Recurrent Human Laryngeal Nerve

    Directory of Open Access Journals (Sweden)

    Andréa Aparecida Ferreira Pascoal

    2014-01-01

    Full Text Available The importance of the recurrent laryngeal nerve in surgery on the anterior region of the neck has motivated many published papers on critical points of its pathway, relationship with the inferior thyroid artery, penetration in the larynx, division outside the larynx, and branches communicating with the internal branch of the superior laryngeal nerve. We analyze the terminal branches of the recurrent laryngeal nerve and their distribution through the laryngeal muscles. 44 laryngeal nerves had been dissected. Most frequently, the recurrent laryngeal nerve presents a division below or at the level of the lower margin of the cricoid cartilage (outside the larynx. One of these branches forms the communication with the internal branch of the superior laryngeal nerve, and the other penetrates the laryngeal space. Above the lower margin of the cricoid cartilage, the inferior laryngeal nerve issues a variable number of branches to muscles (3 to 7: to the posterior cricoarytenoid muscle; to the oblique and transversal arytenoid muscles; and to the lateral cricoarytenoid muscle and the thyroarytenoid muscle.

  13. NRAGE: a potential rheostat during branching morphogenesis.

    Science.gov (United States)

    Nikopoulos, George N; Martins, Joao Ferreira; Adams, Tamara L; Karaczyn, Aldona; Adams, Derek; Vary, Calvin; Oxburgh, Leif; Verdi, Joseph M

    2009-01-01

    Branching morphogenesis is a developmental process characteristic of many organ systems. Specifically, during renal branching morphogenesis, its been postulated that the final number of nephrons formed is one key clinical factor in the development of hypertension in adulthood. As it has been established that BMPs regulate, in part, renal activity of p38 MAP kinase (p38(MAPK)) and it has demonstrated that the cytoplasmic protein Neurotrophin Receptor MAGE homologue (NRAGE) augments p38(MAPK) activation, it was hypothesized that a decrease in the expression of NRAGE during renal branching would result in decreased branching of the UB that correlated with changes in p38(MAPK) activation. To verify this, the expression of NRAGE was reduced in ex vivo kidney explants cultures using antisense morpholino. Morpholino treated ex vivo kidney explants expression were severely stunted in branching, a trait that was rescued with the addition of exogenous GDNF. Renal explants also demonstrated a precipitous drop in p38(MAPK) activation that too was reversed in the presence of recombinant GDNF. RNA profiling of NRAGE diminished ex vivo kidney explants resulted in altered expression of GDNF, Ret, BMP7 and BMPRIb mRNAs. Our results suggested that in early kidney development NRAGE might have multiple roles during renal branching morphogenesis through association with both the BMP and GDNF signaling pathways.

  14. Watershed characteristics and water-quality trends and loads in 12 watersheds in Gwinnett County, Georgia

    Science.gov (United States)

    Joiner, John K.; Aulenbach, Brent T.; Landers, Mark N.

    2014-01-01

    The U.S. Geological Survey, in cooperation with Gwinnett County Department of Water Resources, established a Long-Term Trend Monitoring (LTTM) program in 1996. The LTTM program is a comprehensive, long-term, water-quantity and water-quality monitoring program designed to document and analyze the hydrologic and water-quality conditions of selected watersheds of Gwinnett County, Georgia. Water-quality monitoring initially began in six watersheds and was expanded to another six watersheds in 2001. As part of the LTTM program, streamflow, precipitation, water temperature, specific conductance, and turbidity were measured continuously at the 12 watershed monitoring stations for water years 2004–09. In addition, discrete water-quality samples were collected seasonally from May through October (summer) and November through April (winter), including one base-flow and three stormflow event composite samples, during the study period. Samples were analyzed for nutrients (nitrogen and phosphorus), total organic carbon, trace elements (total lead and total zinc), total dissolved solids, and total suspended sediment (total suspended solids and suspended-sediment concentrations). The sampling scheme was designed to identify variations in water quality both hydrologically and seasonally. The 12 watersheds were characterized for basin slope, population density, land use for 2009, and the percentage of impervious area from 2000 to 2009. Precipitation in water years 2004–09 was about 18 percent below average, and the county experienced exceptional drought conditions and below average runoff in water years 2007 and 2008. Watershed water yields, the percentage of precipitation that results in runoff, typically are lower in low precipitation years and are higher for watersheds with the highest percentages of impervious areas. A comparison of base-flow and stormflow water-quality samples indicates that turbidity and concentrations of total ammonia plus organic nitrogen, total

  15. Organic geochemistry and brine composition in Great Salt, Mono, and Walker Lakes

    Science.gov (United States)

    Domagalski, Joseph L.; Orem, William H.; Eugster, Hans P.

    1989-11-01

    Samples of Recent sediments, representing up to 1000 years of accumulation, were collected from three closed basin lakes (Mono Lake, CA, Walker Lake, NV, and Great Salt Lake, UT) to assess the effects of brine composition on the accumulation of total organic carbon, the concentration of dissolved organic carbon, humic acid structure and diagenesis, and trace metal complexation. The Great Salt Lake water column is a stratified Na-Mg-Cl-SO 4 brine with low alkalinity. Algal debris is entrained in the high density (1.132-1.190 g/cc) bottom brines, and in this region maximum organic matter decomposition occurs by anaerobic processes, with sulfate ion as the terminal electron acceptor. Organic matter, below 5 cm of the sediment-water interface, degrades at a very slow rate in spite of very high pore-fluid sulfate levels. The organic carbon concentration stabilizes at 1.1 wt%. Mono Lake is an alkaline (Na-CO 3-Cl-SO 4) system. The water column is stratified, but the bottom brines are of lower density relative to the Great Salt Lake, and sedimentation of algal debris is rapid. Depletion of pore-fluid sulfate, near l m of core, results in a much higher accumulation of organic carbon, approximately 6 wt%. Walker Lake is also an alkaline system. The water column is not stratified, and decomposition of organic matter occurs by aerobic processes at the sediment-water interface and by anaerobic processes below. Total organic carbon and dissolved organic carbon concentrations in Walker Lake sediments vary with location and depth due to changes in input and pore-fluid sulfate concentrations. Nuclear magnetic resonance studies ( 13C) of humic substances and dissolved organic carbon provide information on the source of the Recent sedimentary organic carbon (aquatic vs. terrestrial), its relative state of decomposition, and its chemical structure. The spectra suggest an algal origin with little terrestrial signature at all three lakes. This is indicated by the ratio of aliphatic to

  16. Nasonia vitripennis (Walker (Hymenoptera: Pteromalidae parasitóide de dípteros muscóides coletado em Itumbiara, Goiás Nasonia vitripennis (Walker (Hymenoptera: Pteromalidae parasitoid of muscoids dipterous collected in Itumbiara, Goias, Brazil

    Directory of Open Access Journals (Sweden)

    C.H. Marchiori

    2004-06-01

    Full Text Available This work reports the occurrence of parasitoid Nasonia vitripennis (Walker (Hymenoptera: Pteromalidae parasitizing pupae of flies (Diptera in different substrata in Itumbiara, Goiás. The pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergence of flies or their parasitoids. From May 1998 through April 2002, 737 parasitoids were collected in human feces, cattle liver, chicken, fish and cattle kidney. The prevalence of parasitism was 67.8%.

  17. Lithology, Geochemistry and Paleomagnetism of the Table Mountain Formation at the Little Walker Caldera

    Science.gov (United States)

    Schubert, R.; Pluhar, C. J.; Carlson, C. W.; Jones, S. A.

    2015-12-01

    West of Bridgeport Valley near the Central Sierra Nevada crest, the Little Walker Caldera (LWC) erupted Stanislaus Group lavas and tuffs during the Late Miocene. Remnants of these rocks are now distributed from the western Sierra Nevada foothills across the range and into the Walker Lane. This wide distribution is attributed to the lavas flowing down paleochannels, which provide an excellent marker for deformation over the last 10 Ma. Priest (1978) identified a thick section of these lavas along Flatiron Ridge, the southeast margin of the LWC, which our preliminary data suggests may correlate with lavas in the Sweetwater Mountains to the northeast and at Rancheria Mtn near Hetch Hetchy to the southwest. The oldest unit in the Stanislaus group is the Table Mountain Formation, a trachyandesite. At Priest's measured section it is divided into three members. By our measurements, the Lower Member (Tmtl) is 256 meters thick, has a fine-grained groundmass with plagioclase and augite phenocrysts (<0.5 cm), and the presence of augite phenocrysts distinguishes it from the other members. Some Tmtl flows have chalcedony amigdules. Overlying this, the Large Plagioclase member (Tmtp) is 43.5 meters thick. Distinguished by (~1 cm) plagioclase and occasional small olivine phenocrysts. The Upper Member (Tmtu) is 116 meters thick, very fine-grained and often platy. Tmtl has a distinctive northwest-oriented normal polarity and geochemistry, similar to several localities at Rancheria Mtn. Tmtu has a reversed polarity similar to the polarity of Table Mountain Formation in the Sweetwater Mountains and lavas that directly underlie the ~9.5 Ma Tollhouse Flat member of the Eureka Valley Tuff at Rancheria Mtn. Thus, our preliminary data suggest that the lower member at Priest's Measured Section could correlate to the normal polarity samples at Rancheria Mtn. Also, that the upper Member reversed-polarity samples may correlate with lavas both at the Sweetwater Mountains and Rancheria Mtn

  18. Landscape planning for agricultural non-point source pollution reduction. II. Balancing watershed size, number of watersheds, and implementation effort.

    Science.gov (United States)

    Maxted, Jeffrey T; Diebel, Matthew W; Vander Zanden, M Jake

    2009-01-01

    Agricultural non-point source (NPS) pollution poses a severe threat to water quality and aquatic ecosystems. In response, tremendous efforts have been directed toward reducing these pollution inputs by implementing agricultural conservation practices. Although conservation practices reduce pollution inputs from individual fields, scaling pollution control benefits up to the watershed level (i.e., improvements in stream water quality) has been a difficult challenge. This difficulty highlights the need for NPS reduction programs that focus efforts within target watersheds and at specific locations within target watersheds, with the ultimate goal of improving stream water quality. Fundamental program design features for NPS control programs--i.e., number of watersheds in the program, total watershed area, and level of effort expended within watersheds--have not been considered in any sort of formal analysis. Here, we present an optimization model that explores the programmatic and environmental trade-offs between these design choices. Across a series of annual program budgets ranging from $2 to $200 million, the optimal number of watersheds ranged from 3 to 27; optimal watershed area ranged from 29 to 214 km(2); and optimal expenditure ranged from $21,000 to $35,000/km(2). The optimal program configuration was highly dependent on total program budget. Based on our general findings, we delineated hydrologically complete and spatially independent watersheds ranging in area from 20 to 100 km(2). These watersheds are designed to serve as implementation units for a targeted NPS pollution control program currently being developed in Wisconsin.

  19. Watershed Ecohydrology: How Do Vegetation Patterns and Climate Affect Watershed Storage and Connectivity?

    Science.gov (United States)

    Nippgen, F.; McGlynn, B. L.; Emanuel, R. E.

    2015-12-01

    Topography and soils have long been recognized as mediators of runoff source areas, but the effect of vegetation patterns on subsurface throughflow is less well understood. While numerous studies have shown that vegetation removal generally leads to increases in streamflow, few studies have examined the intersection between patterns of evapotranspiration and topographically driven patterns of throughflow generation and connectivity. We applied a parsimonious but spatially distributed watershed modeling framework (WECOH: Watershed ECOHydrology Model) to a snow dominated watershed in central Montana to elucidate how different vegetation scenarios and climate forcing can affect the temporal evolution of storage distributions and watershed connectivity. We derived spatially distributed snowmelt and rainfall input from two NRCS SNOTEL sites located in the experimental watershed and actual evapotranspiration from a co-located eddy-covariance tower. We generated different vegetation scenarios to simulate forest harvesting and compared streamflow response, spatial distribution of storage, and runoff source areas across scenarios. Our work aims at better understanding how the intersection of vegetation and topography mediates hydrologic response.

  20. Developing Participatory Models of Watershed Management in the Sugar Creek Watershed (Ohio, USA

    Directory of Open Access Journals (Sweden)

    Jason Shaw Parker

    2009-02-01

    Full Text Available The US Environmental Protection Agency (USEPA has historically used an expert-driven approach to water and watershed management. In an effort to create regulatory limits for pollution-loading to streams in the USA, the USEPA is establishing limits to the daily loading of nutrients specific to each watershed, which will affect many communities in America. As a part of this process, the Ohio Environmental Protection Agency ranked the Sugar Creek Watershed as the second "most-impaired" watershed in the State of Ohio. This article addresses an alternative approach to watershed management and that emphasises a partnership of farmers and researchers, using community participation in the Sugar Creek to establish a time-frame with goals for water quality remediation. Of interest are the collaborative efforts of a team of farmers, researchers, and agents from multiple levels of government who established this participatory, rather than expert-driven, programme. This new approach created an innovative and adaptive model of non-point source pollution remediation, incorporating strategies to address farmer needs and household decision making, while accounting for local and regional farm structures. In addition, this model has been adapted for point source pollution remediation that creates collaboration among local farmers and a discharge-permitted business that involves nutrient trading.

  1. Watershed Conservation in the Long Run

    DEFF Research Database (Denmark)

    Kaiser, Brooks

    2014-01-01

    We studied unanticipated long-run outcomes of conservation activities that occurred in forested watersheds on O`ahu, Hawaii, in the early twentieth century. The initial general impetus for the conservation activities was to improve irrigation surface water flow for the sugar industry. Industry...... concentration facilitated conservation of entire ecosystems. We investigate the benefits that accrued through dynamic linkages of the hydrological cycle and groundwater aquifer system. This provides a clear example of the need to consider integrated watershed effects, industrial structure, and linkages...... in groundwater recharge levels from these activities, with a lower bound benefit–cost ratio of 7.1–18.2. This lower-bound excludes returns from such high value, yet controversial to measure, amenities as species preservation....

  2. Thermodynamic watershed hydrological model: Constitutive relationship

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The representative elementary watershed (REW) approach proposed by Reggiani et al. was the first attempt to develop scale adaptable equations applicable directly at the macro scale. Tian et al. extended the initial definition of REW for simulating the energy related processes, and re-organized the deriving procedure of balance equations so that additional sub-regions and substances could be easily incorpo-rated. The resultant ordinary differential equation set can simulate various hydro-logical processes in a physically reasonable way. However, constitutive and geo-metric relationships have not been developed for Tian et al.’s equation set, which are necessary for the thermodynamic watershed hydrological model to apply in hydrological modeling practice. In this work, the constitutive equations for mass exchange terms and momentum exchange terms were developed as well as geo-metric relationships. The closed ordinary differential equation set with nine equa-tions was finally obtained.

  3. Thermodynamic watershed hydrological model: Constitutive relationship

    Institute of Scientific and Technical Information of China (English)

    TIAN FuQiang; HU HePing; LEI ZhiDong

    2008-01-01

    The representative elementary watershed (REW) approach proposed by Reggiani et al. Was the first attempt to develop scale adaptable equations applicable directly at the macro scale. Tian et al. Extended the initial definition of REW for simulating the energy related processes, and re-organized the deriving procedure of balance equations so that additional sub-regions and substances could be easily incorpo- rated. The resultant ordinary differential equation set can simulate various hydro- logical processes in a physically reasonable way. However, constitutive and geo- metric relationships have not been developed for Tian et al.'s equation set, which are necessary for the thermodynamic watershed hydrological model to apply in hydrological modeling practice. In this work, the constitutive equations for mass exchange terms and momentum exchange terms were developed as well as geo- metric relationships. The closed ordinary differential equation set with nine equations was finally obtained.

  4. Comparative study of two female African-American Writers in 20 Centu-ry-Alice Walker VS. Toni Morriso

    Institute of Scientific and Technical Information of China (English)

    桂生义

    2013-01-01

    Toni Morrison and Alice Walker are among the most outstanding female African-American writers in Contemporary American Literature. Their works have been popular since 1960s to now. Although Walker and Morrison grew up under differ⁃ent family environments, they had the same experience of witnessing African-American women’s movements in last Century;therefore, they reached an agreement on writing thoughts and contents. For instance, they both referred to Racism, Sexism and“Womanism”in many of their works. This dissertation studies about the two authors’difference and sameness descriptions on Af⁃rican-American women’s identities, social status, rights, powers and fates,and to express their self-consciousness and bright prospection after experiencing the most painful encounters through comparative study on two of their short stories—Everyday Use and Recitatif.

  5. Henri Cartier-Bresson / Walker Evans : Photographier l’Amérique (1929-1947

    Directory of Open Access Journals (Sweden)

    François Brunet

    2009-08-01

    Full Text Available Dans un mot adressé en 2001 à Peter Galassi, conservateur de la photographie au MOMA, Henri Cartier-Bresson, alors âgé de quatre-vingt-treize ans, écrivait plaisamment — mais non pas complaisamment : « If it had not been for the challenge of the work of Walker Evans, I don’t think I would have remained a fotographer » (« sans le défi constitué par le travail de Walker Evans, je ne crois pas que je serais resté fotographe ». Pour fêter le centenaire de Cartier-Bresson, c’est ce défi — plutôt ...

  6. Seizure and unilateral facial nerve paralysis in a newborn with Dandy-Walker malformation – A case report

    Directory of Open Access Journals (Sweden)

    Subhajit Bhakta

    2014-01-01

    Full Text Available The Dandy-Walker syndrome (DWS is a rare posterior fossa malformation. It can have a varied presentation depending on the age. A newborn presenting with neonatal seizure along with unilateral facial nerve palsy is rather a rare presentation of DWS and very few such cases were reported in the past. We are reporting a case of a newborn male baby presenting with neonatal seizure within 48 hrs of birth along with right sided LMN type facial nerve palsy which on due course of investigation revealed as a case of Dandy–Walker malformation. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-1, 48-51 DOI: http://dx.doi.org/10.3126/jcmsn.v9i1.9673

  7. Global Existence of Solutions for the Einstein-Boltzmann System with Cosmological Constant in the Robertson-Walker Space-time

    CERN Document Server

    Takou, E; Takou, Etienne; Noutchegueme, Norbert

    2005-01-01

    We prove a global in time existence theorem for the initial values problem for the Einstein-Boltzmann system with cosmological constant and arbitrarily large initial data, in the spatially homogeneous case, in a Robertson-Walker space-time.

  8. Differences in muscle activity and temporal step parameters between Lokomat guided walking and treadmill walking in post-stroke hemiparetic patients and healthy walkers

    National Research Council Canada - National Science Library

    Klaske van Kammen; Anne M Boonstra; Lucas H V van der Woude; Heleen A Reinders-Messelink; Rob den Otter

    2017-01-01

    .... To purposefully employ the Lokomat for training, it is important to understand (1) how Lokomat guided walking affects muscle activity following stroke and how these effects differ between patients and healthy walkers, (2...

  9. Prof. John Wood, Chief Executive Designate, Dr Gordon Walker, Directorate, Chief Executive, Prof. Ken J. Peach, Head of the Particle Physics Department, CLRC Rutherford Appleton Laboratory, United Kingdom

    CERN Document Server

    Patrice Loïez

    2001-01-01

    L. to. r.: Dr. Ian Wilson, CLIC Deputy Study Leader, Prof. Ken J. Peach, Head of the Particle Physics Department, Prof. John Wood, Chief Executive Designate, Dr. Gordon Walker, Directorate, Chief Executive

  10. Development of SPAWM: selection program for available watershed models.

    Science.gov (United States)

    Cho, Yongdeok; Roesner, Larry A

    2014-01-01

    A selection program for available watershed models (also known as SPAWM) was developed. Thirty-three commonly used watershed models were analyzed in depth and classified in accordance to their attributes. These attributes consist of: (1) land use; (2) event or continuous; (3) time steps; (4) water quality; (5) distributed or lumped; (6) subsurface; (7) overland sediment; and (8) best management practices. Each of these attributes was further classified into sub-attributes. Based on user selected sub-attributes, the most appropriate watershed model is selected from the library of watershed models. SPAWM is implemented using Excel Visual Basic and is designed for use by novices as well as by experts on watershed modeling. It ensures that the necessary sub-attributes required by the user are captured and made available in the selected watershed model.

  11. Application of a virtual watershed in academic education

    Directory of Open Access Journals (Sweden)

    A. L. Horn

    2005-01-01

    Full Text Available Hydrologic models of watersheds often represent complex systems which are difficult to understand regarding to their structure and dynamics. Virtual watersheds, i.e. watersheds which exist only in the virtual reality of a computer system, are an approach to simplify access to this real-world complexity. In this study we present the virtual watershed KIELSHED-1, a 117 km2 v-shaped valley with grassland on a "Cambisol" soil type. Two weather scenarios are delivered with the watershed: a simplified artificial weather scenario based on long-term data of a German weather station as well as an unmodified data record. The input data and parameters are compiled according to the conventions of the SWAT 2000 hydrological model. KIELSHED-1 is mainly used for education, and illustrative application examples, i.e. calculation of water balance, model calibration, development of land use scenarios, give an insight to the capabilities of the virtual watershed.

  12. Structure-Property Relationships for Branched Worm-Like Micelles

    Science.gov (United States)

    Beaucage, Gregory; Rai, Durgesh

    2013-03-01

    Micellar solutions can display a wide range of phase structure as a function of counter ion content, surfactant concentration, and the presence of ternary components. Under some conditions, common to consumer products, extended cylindrical structures that display persistence and other chain features of polymers are produced. These worm-like micelles (WLMs) can form branched structures that dynamically change under shear and even in quiescent conditions. The rheology of these branched WLMs is strongly dependent on migration of the branch points, and the dynamics of branch formation and removal. Persistence and other polymer-based descriptions are also of importance. We have recently developed a scattering model for branched polyolefins and other topologically complex materials that can quantify the branching density, branch length, branch functionality and the hyperbranch (branch-on-branch) content of polymers. This work is being extended to study branching in WLMs in work coupled with Ron Larson at UMich to predict rheological properties.

  13. Payments for watershed services: Opportunities and realities

    OpenAIRE

    Bond, I.

    2007-01-01

    Metadata only record "Many nations have found that regulatory approaches to land and water management have a limited impact. An alternative is to create incentives for sound management under mechanisms known as payments for ecosystem services. It is a simple idea: people who look after ecosystems that benefit others should be recognised and rewarded. In the case of watersheds, downstream beneficiaries of wise upstream land and water use should compensate the stewards. To be effective, thes...

  14. Watershed modeling at the Savannah River Site.

    Energy Technology Data Exchange (ETDEWEB)

    Vache, Kellie [Oregon State University

    2015-04-29

    The overall goal of the work was the development of a watershed scale model of hydrological function for application to the US Department of Energy’s (DOE) Savannah River Site (SRS). The primary outcomes is a grid based hydrological modeling system that captures near surface runoff as well as groundwater recharge and contributions of groundwater to streams. The model includes a physically-based algorithm to capture both evaporation and transpiration from forestland.

  15. Granite Exfoliation, Cosumnes River Watershed, Somerset, California

    Science.gov (United States)

    Crockett, I. Q.; Neiss-Cortez, M.

    2015-12-01

    In the Sierra Nevada foothills of California there are many exposed granite plutons within the greater Sierra Nevada batholith. As with most exposed parts of the batholith, these granite slabs exfoliate. It is important to understand exfoliation for issues of public safety as it can cause rock slides near homes, roads, and recreation areas. Through observation, measuring, and mapping we characterize exfoliation in our Cosumnes River watershed community.

  16. [Reseña] Charles F. Walker, Smoldering ashes: Cusco and the creation of Republican Peru, 1780-1840

    OpenAIRE

    P. Latasa

    2002-01-01

    Reseña del libro de Walker, Charles F.: De Túpac Amaru a Gamarra: Cusco y la formación del Perú Republicano, 1780-1840, Cusco, Centro de Estudios Regionales Andinos “Bartolomé de Las Casas”, 1999, 316 págs. [Smoldering ashes: Cusco and the creation of Republican Peru, 1780-1840, Durham, N.C., Duke University Press, 1999].

  17. Class of solutions of the Wheeler-DeWitt equation in the Friedmann-Robertson-Walker universe

    Science.gov (United States)

    Vieira, H. S.; Bezerra, V. B.

    2016-07-01

    We show that the solutions of the Wheeler-DeWitt equation in a homogeneous and isotropic universe are given by triconfluent Heun functions for the spatially closed, flat, and open geometries of the Friedmann-Robertson-Walker universe filled with different forms of energy. In a matter-dominated universe, we find the polynomial solution and the energy density spectrum. In the cases of radiation-dominated and vacuum universes, there are no polynomial solutions as shown.

  18. New Lethal Skeletal Dysplasia with Dandy-Walker Malformation, Congenital Heart Defects, Abnormal Thumbs, Hypoplastic Genitalia, and Distinctive Facies

    Science.gov (United States)

    Stevens, Cathy A.; Lachman, Ralph S.

    2011-01-01

    We report on two sibs with a lethal form of bone dysplasia with distinctive skeletal findings including rhizomelic and mesomelic limb shortening, hooked clavicles, dumbbell femurs, and absence of talus and calcaneus ossification. Other clinical features include Dandy-Walker malformation, congenital heart defects, joint contractures, genital hypoplasia, and distinctive facial features. These sibs appear to have a previously undescribed skeletal dysplasia, which is most likely inherited in an autosomal recessive fashion. PMID:20602491

  19. Naringin Inhibits Tumor Growth And Reduces Interleukin-6 And Tumor Necrosis Factor α Levels In Rats With Walker 256 Carcinosarcoma

    OpenAIRE

    Camargo C.A.; Gomes-Marcondes M.C.C.; Wutzki N.C.; Aoyama H.

    2012-01-01

    The flavonoid naringin is a polyphenolic compound that naturally occurs in citrus. Patients with cancer generally present features of malnutrition and cachexia. Levels of the proinflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) are raised in patients with cancer. This study was designed to analyze the in vivo effect of naringin in the therapeutic treatment of rats bearing Walker 256 carcinosarcoma (W256). Rats were treated intraperitoneally with different doses o...

  20. Quantum cosmology on (k = -1)-Friedmann-Robertson-Walker Universe evolving from stiff matter era to the dust dominated one

    Science.gov (United States)

    Dariescu, Marina-Aura; Dariescu, Ciprian

    2017-01-01

    This work is devoted to the spatially open Friedmann-Robertson-Walker (FRW) Universe evolving from the stiff matter era to the dust dominated one. Within the quantum analysis based on the Wheeler-DeWitt equation, we derive the wave function of the (k = -1)-FRW Universe with combined matter sources. On the classical level, one has to deal with the Friedmann equation which leads on a dependence of the scale function on time generally expressed from functional relations involving elliptic integrals.

  1. Citizen participation in collaborative watershed partnerships.

    Science.gov (United States)

    Koehler, Brandi; Koontz, Tomas M

    2008-02-01

    Collaborative efforts are increasingly being used to address complex environmental problems, both in the United States and abroad. This is especially true in the growing field of collaborative watershed management, where diverse stakeholders work together to develop and advance water-quality goals. Active citizen participation is viewed as a key component, yet groups often struggle to attract and maintain citizen engagement. This study examined citizen participation behavior in collaborative watershed partnerships by way of a written survey administered to citizen members of 12 collaborative watershed groups in Ohio. Results for the determination of who joins such groups were consistent with the dominant-status model of participation because group members were not demographically representative of the broader community. The dominant-status model, however, does not explain which members are more likely to actively participate in group activities. Instead, individual characteristics, including political activity, knowledge, and comfort in sharing opinions with others, were positively correlated with active participation. In addition, group characteristics, including government-based membership, rural location, perceptions of open communication, perceptions that the group has enough technical support to accomplish its goals, and perceived homogeneity of participant opinions, were positively correlated with active participation. Overall, many group members did not actively participate in group activities.

  2. Cycling of Organoarsenic Compounds in Agricultural Watersheds

    Science.gov (United States)

    Schreiber, M. E.; Chambers, D. B.; White, J. S.

    2004-12-01

    The use of the organoarsenical roxarsone, added to poultry feed to increase weight gain, results in elevated arsenic concentrations (10-50 mg/kg) in poultry litter. This litter is extensively applied to crop fields and pastures, both as a fertilizer and as a waste disposal technique, in agricultural regions. Using a combination of field sampling and laboratory experiments, we investigated the sources and sinks of arsenic within soils and natural waters in an agricultural watershed in the Shenandoah Valley of Virginia, USA, an area of intense poultry production. Surface, ground, and soil waters were collected in an instrumented field site to examine arsenic and other litter-derived species in different hydrologic compartments and different settings within the field site. We collected soil cores of the Frederick series, common in the Shenandoah Valley, from several areas experiencing different litter application histories in the valley to examine relationships between arsenic and physico-chemical properties of the soils. Last, we conducted a series of batch experiments to examine adsorption and biotransformation characteristics of roxarsone within Ap and Bt soil horizons of the Frederick soils. Results of these combined studies document a complex yet intriguing cycling of arsenic through the watershed, which will provide useful information for management of poultry litter in agricultural watersheds.

  3. Approximate KMS states for scalar and spinor fields in Friedmann-Robertson-Walker spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Dappiaggi, Claudio; Hack, Thomas-Paul [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik; Pinamonti, Nicola [Roma ' ' Tor Vergata' ' Univ. (Italy). Dipt. di Matematica

    2010-09-15

    We construct and discuss Hadamard states for both scalar and Dirac spinor fields in a large class of spatially flat Friedmann-Robertson-Walker spacetimes characterised by an initial phase either of exponential or of power-law expansion. The states we obtain can be interpreted as being in thermal equilibrium at the time when the scale factor a has a specific value a = a{sub 0}. In the case a{sub 0} = 0, these states fulfil a strict KMS condition on the boundary of the spacetime, which is either a cosmological horizon, or a Big Bang hypersurface. Furthermore, in the conformally invariant case, they are conformal KMS states on the full spacetime. However, they provide a natural notion of an approximate KMS state also in the remaining cases, especially for massive fields. On the technical side, our results are based on a bulk-to-boundary reconstruction technique already successfully applied in the scalar case and here proven to be suitable also for spinor fields. The potential applications of the states we find range over a broad spectrum, but they appear to be suited to discuss in particular thermal phenomena such as the cosmic neutrino background or the quantum state of dark matter. (orig.)

  4. Innovative use of an automated horse walker when breaking in young horses.

    Science.gov (United States)

    Murphy, Jack

    2008-01-01

    There is an inherent element of risk associated with "backing" and riding the previously unbroken horse. If training proceeds too quickly, conflict behaviors may result from the simultaneous application of too many cues. Automated horse walkers (AHW) facilitate the exercising of several horses concurrently at walk or trot for warm-up, cool-down, fitness programs, and rehabilitation purposes. The objective of this study was to investigate if backing the horse within the AHW was an appropriate training method. Ten horses (3-year-olds) took part in this study. They began training within the AHW with a simple bridle and protective boots. A handler subsequently long-reined the horses within the AHW when they wore rollers, side reins, and a saddle. When considered appropriate, the handler went from jumping beside the horse to lying over the saddle to sitting astride the horse within the AHW. The horses habituated to this innovative approach quickly without evidence of conflict behavior. The handler rode the horses from the AHW after approximately 4 riding episodes of this innovative training system.

  5. A measure on the set of compact Friedmann-Lemaitre-Robertson-Walker models

    Energy Technology Data Exchange (ETDEWEB)

    Roukema, Boudewijn F [Torun Centre for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87-100 Torun (Poland); Blanloeil, Vincent [IRMA, Departement de Mathematiques, Universite de Strasbourg, 7 rue Rene Descartes, 67084 Strasbourg, Cedex (France)

    2010-12-21

    Compact, flat Friedmann-Lemaitre-Robertson-Walker (FLRW) models have recently regained interest as a good fit to the observed cosmic microwave background temperature fluctuations. However, it is generally thought that a globally, exactly flat FLRW model is theoretically improbable. Here, in order to obtain a probability space on the set F of compact, comoving, 3-spatial sections of FLRW models, a physically motivated hypothesis is proposed, using the density parameter {Omega} as a derived rather than fundamental parameter. We assume that the processes that select the 3-manifold also select a global mass-energy and a Hubble parameter. The requirement that the local and global values of {Omega} are equal implies a range in {Omega} that consists of a single real value for any 3-manifold. Thus, the obvious measure over F is the discrete measure. Hence, if the global mass-energy and Hubble parameter are a function of 3-manifold choice among compact FLRW models, then probability spaces parametrized by {Omega} do not, in general, give a zero probability of a flat model. Alternatively, parametrization by a spatial size parameter, the injectivity radius r{sub inj}, suggests the Lebesgue measure. In this case, the probability space over the injectivity radius implies that flat models occur almost surely (a.s.), in the sense of probability theory, and non-flat models a.s. do not occur.

  6. Modelling the effects of the sterile insect technique applied to Eldana saccharina Walker in sugarcane

    Directory of Open Access Journals (Sweden)

    L Potgieter

    2012-12-01

    Full Text Available A mathematical model is formulated for the population dynamics of an Eldana saccharina Walker infestation of sugarcane under the influence of partially sterile released insects. The model describes the population growth of and interaction between normal and sterile E.saccharina moths in a temporally variable, but spatially homogeneous environment. The model consists of a deterministic system of difference equations subject to strictly positive initial data. The primary objective of this model is to determine suitable parameters in terms of which the above population growth and interaction may be quantified and according to which E.saccharina infestation levels and the associated sugarcane damage may be measured. Although many models have been formulated in the past describing the sterile insect technique, few of these models describe the technique for Lepidopteran species with more than one life stage and where F1-sterility is relevant. In addition, none of these models consider the technique when fully sterile females and partially sterile males are being released. The model formulated is also the first to describe the technique applied specifically to E.saccharina, and to consider the economic viability of applying the technique to this species. Pertinent decision support is provided to farm managers in terms of the best timing for releases, release ratios and release frequencies.

  7. Dispersion, Topological Scattering, and Self-Interference in Multiply Connected Robertson-Walker Cosmologies

    CERN Document Server

    Tomaschitz, R

    1994-01-01

    We investigate scattering effects in open Robertson-Walker cosmologies whose spacelike slices are multiply connected hyperbolic manifolds. We work out an example in which the 3-space is infinite and has the topology of a solid torus. The world-lines in these cosmologies are unstable, and classical probability densities evolving under the horospherical geodesic flow show dispersion, as do the densities of scalar wave packets. The rate of dispersion depends crucially on the expansion factor, and we calculate the time evolution of their widths. We find that the cosmic expansion can confine dispersion: The diameter of the domain of chaoticity in the 3-manifold provides the natural, time-dependent length unit in an infinite, multiply connected universe. In a toroidal 3-space manifold this diameter is just the length of the limit cycle. On this scale we find that the densities take a finite limit width in the late stage of the expansion. In the early stage classical densities and conformally coupled fields approach...

  8. Ascending auditory interneurons in the cricket Teleogryllus commodus (Walker): comparative physiology and direct connections with afferents.

    Science.gov (United States)

    Hennig, R M

    1988-05-01

    Ascending auditory interneurons of the cricket, Teleogryllus commodus (Walker), were investigated using simultaneous intracellular and extracellular recording in order to identify units which had previously been characterized only by extracellular recording. The morphology and physiology of the large adapting unit (LAU: Fig. 1) and of the small tonic unit (STU: Fig. 2) of Teleogryllus correspond well to those of the ascending neuron 2 (AN2) and the ascending neuron 1 (AN1) of Gryllus (Figs. 1, 2), respectively. A summary of the ascending auditory interneurons described by various authors in 5 species of crickets is presented in order to establish common identities. Physiological evidence for direct connections between auditory afferents and the ascending auditory interneurons AN1 (STU) and AN2 (LAU) is presented. Simultaneous intracellular recordings from receptors and interneurons in response to sound as well as the activity of auditory interneurons upon electrical stimulation of the tympanal nerve reveal short and constant latencies of receptor-evoked synaptic activity in AN1 (STU) and AN2 (LAU).

  9. Chronic Glibenclamide Treatment Attenuates Walker-256 Tumour Growth in Prediabetic Obese Rats.

    Science.gov (United States)

    da Silva Franco, Claudinéia Conationi; Previate, Carina; de Barros Machado, Kátia Gama; Piovan, Silvano; Miranda, Rosiane Aparecida; Prates, Kelly Valério; Moreira, Veridiana Mota; de Oliveira, Júlio Cezar; Barella, Luiz Felipe; Gomes, Rodrigo Mello; Francisco, Flávio Andrade; Martins, Isabela Peixoto; Pavanello, Audrei; Ribeiro, Tatiane Aparecida; Tófolo, Laize Peron; Malta, Ananda; de Souza, Aline Amenencia; Alves, Vander Silva; da Silva Silveira, Sandra; Marçal Natali, Maria Raquel; Fernando Besson, Jean Carlos; de Morais, Hely; de Souza, Helenir Medri; de Sant Anna, Juliane Rocha; Alves de Castro Prado, Marialba Avezum; de Freitas Mathias, Paulo Cezar

    2017-01-01

    The sulphonylurea glibenclamide (Gli) is widely used in the treatment of type 2 diabetes. In addition to its antidiabetic effects, low incidences of certain types of cancer have been observed in Gli-treated diabetic patients. However, the mechanisms underlying this observation remain unclear. The aim of the present work was to evaluate whether obese adult rats that were chronically treated with an antidiabetic drug, glibenclamide, exhibit resistance to rodent breast carcinoma growth. Neonatal rats were treated with monosodium L-glutamate (MSG) to induce prediabetes. Control and MSG groups were treated with Gli (2 mg/kg body weight/day) from weaning to 100 days old. After Gli treatment, the control and MSG rats were grafted with Walker-256 tumour cells. After 14 days, grafted rats were euthanized, and tumour weight as well as glucose homeostasis were evaluated. Treatment with Gli normalized tissue insulin sensitivity and glucose tolerance, suppressed fasting hyperinsulinaemia, reduced fat tissue accretion in MSG rats, and attenuated tumour growth by 27% in control and MSG rats. Gli treatment also resulted in a large reduction in the number of PCNA-positive tumour cells. Although treatment did improve the metabolism of pre-diabetic MSG-rats, tumour growth inhibition may be a more direct effect of glibenclamide. © 2017 The Author(s). Published by S. Karger AG, Basel.

  10. Preserving Information from the Beginning to the End of Time in a Robertson-Walker Universe

    CERN Document Server

    Mancini, Stefano; Wilde, Mark M

    2014-01-01

    Preserving information stored in a physical system subjected to noise can be modeled in a communication-theoretic paradigm, in which storage and retrieval correspond to an input encoding and output decoding, respectively. The encoding and decoding are then constructed in such a way as to protect against the action of a given noisy quantum channel. This paper considers the situation in which the noise is not due to technological imperfections, but rather to the physical laws governing the evolution of the universe. In particular, we consider the dynamics of quantum systems under a Robertson-Walker spacetime and find that the noise imparted to them is equivalent to the well known amplitude damping channel. Since one might be interested in preserving both classical and quantum information in such a scenario, we study trade-off coding strategies and determine a region of achievable rates for the preservation of both kinds of information. As a byproduct we also determine a trade-off between achievable rates of cla...

  11. Development and Leaf Consumption by Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) Reared on Leaves of Agroenergy Crops.

    Science.gov (United States)

    Cabezas, M F; Nava, D E; Geissler, L O; Melo, M; Garcia, M S; Krüger, R

    2013-12-01

    Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) is a polyphagous pest that threatens more than 24 species of crop plants including those used for biodiesel production such as Ricinus communis (castor bean), Jatropha curcas (Barbados nut), and Aleurites fordii (tung oil tree). The development and leaf consumption by S. cosmioides reared on leaves of these three species were studied under controlled laboratory conditions. The egg-to-adult development time of S. cosmioides was shortest when reared on castor bean leaves and longest when reared on tung oil tree leaves. Larvae reared on castor bean and Barbados nut leaves had seven instars, whereas those reared on tung oil tree leaves had eight. Females originating from larvae reared on castor bean and Barbados nut leaves showed greater fecundity than did females originating from larvae reared on tung oil tree leaves. Insects fed on castor bean leaves had shorter life spans than those fed on tung oil tree and Barbados nut leaves although the oviposition period did not differ significantly. The intrinsic and finite rates of increase were highest for females reared on castor bean leaves. Total leaf consumption was highest for larvae reared on tung oil tree leaves and lowest for those reared on Barbados nut leaves. We conclude that castor bean is a more appropriate host plant for the development of S. cosmioides than are Barbados nut and tung oil tree.

  12. Synopsis of the 6th Walker's Cay Colloquium on Cancer Vaccines and Immunotherapy

    Directory of Open Access Journals (Sweden)

    Marincola Francesco M

    2004-06-01

    Full Text Available Abstract The 6th annual Cancer Vaccines and Immunotherapy Colloquium at Walker's Cay was held under the auspices of the Albert B. Sabin Vaccine Institute on March 10–13, 2004. The Colloquium consisted of a select group of 34 scientists representing academia, biotechnology and pharmaceutical industry. The main goal of this gathering was to promote in a peaceful and comfortable environment exchanges between basic and clinical science. The secondary benefit was to inspire novel bench to bedside ventures and at the same time provide feed back about promising and/or disappointing clinical results that could help re-frame some scientific question or guide the design of future trials. Several topics were covered that included tumor antigen discovery and validation, platforms for vaccine development, tolerance, immune suppression and tumor escape mechanisms, adoptive T cell therapy and dendritic cell-based therapies, clinical trials and assessment of response. Here we report salient points raised by speakers or by the audience during animated discussion that followed each individual presentation.

  13. "Between what we know and what we do not know": Alice Munro's 'Walker Brothers Cowboy'

    Directory of Open Access Journals (Sweden)

    Aloka Patel

    2014-05-01

    Full Text Available Narratives of growing-up or coming-of-age, which have traditionally been referred to as Bildungsromane have particularly appealed to and inspired women writers of the twentieth and twenty-first centuries. Especially for women writers of minority and ethnic groups from former European colonies the Bildungsroman has transformed into a discursive tool to deconstruct imperialism and resist discriminations of race, class and sex, and to articulate multiple problems relating to the understanding of their identity. Such fictions by women seem to claim that women's experience of life and reality are different from that of men. Even as the experiences of the girl child are different from those of boys, literary representation of experiences of certain events in life as catalytic in the development of a child growing up in a particular culture, community, and family, are in my opinion, to certain extent similar irrespective of the gender of the writer or the protagonist. In this regard this paper shall focus on Alice Munro's short story 'Walker Brothers Cowboy' (1968 as a narrative of growing up of a female protagonist, not into a gendered being but a more mature individual in relationship with her immediate family and society. At the same time this essay shall also discuss the psychological development of the narrator's father as perceived by his daughter through memory and narrative, which will emphasize on human relationships as primarily determining an individual's identity and selfhood.

  14. The Zero Active Mass Condition in Friedmann-Robertson-Walker Cosmologies

    CERN Document Server

    Melia, Fulvio

    2016-01-01

    Many cosmological measurements today suggest that the Universe is expanding at a constant rate. This is inferred from the observed age versus redshift relationship and various distance indicators, all of which point to a cosmic equation of state (EoS) p=-rho/3, where rho and p are, respectively, the total energy density and pressure of the cosmic fluid. It has recently been shown that this result is not a coincidence and simply confirms the fact that the symmetries in the Friedmann-Robertson-Walker (FRW) metric appear to be viable only for a medium with zero active mass, i.e., rho+3p=0. In their latest paper, however, Kim, Lasenby and Hobson have provided what they believe to be a counter argument to this conclusion. Here, we show that these authors are merely repeating the conventional mistake of incorrectly placing the observer simultaneously in a co-moving frame, where the lapse function g_tt is coordinate dependent when rho+3p is not 0, and a supposedly different, free-falling frame, in which g_tt=1, impl...

  15. The Walker 256 Breast Cancer Cell- Induced Bone Pain Model in Rats.

    Science.gov (United States)

    Shenoy, Priyank A; Kuo, Andy; Vetter, Irina; Smith, Maree T

    2016-01-01

    The majority of patients with terminal breast cancer show signs of bone metastasis, the most common cause of pain in cancer. Clinically available drug treatment options for the relief of cancer-associated bone pain are limited due to either inadequate pain relief and/or dose-limiting side-effects. One of the major hurdles in understanding the mechanism by which breast cancer causes pain after metastasis to the bones is the lack of suitable preclinical models. Until the late twentieth century, all animal models of cancer induced bone pain involved systemic injection of cancer cells into animals, which caused severe deterioration of animal health due to widespread metastasis. In this mini-review we have discussed details of a recently developed and highly efficient preclinical model of breast cancer induced bone pain: Walker 256 cancer cell- induced bone pain in rats. The model involves direct localized injection of cancer cells into a single tibia in rats, which avoids widespread metastasis of cancer cells and hence animals maintain good health throughout the experimental period. This model closely mimics the human pathophysiology of breast cancer induced bone pain and has great potential to aid in the process of drug discovery for treating this intractable pain condition.

  16. Integrating SLAM with existing evidence: Comment on Walker and Hickok (2015).

    Science.gov (United States)

    Goldrick, Matthew

    2016-04-01

    Walker and Hickok (Psychonomic Bulletin & Review doi:10.3758/s13423-015-0903-7, 2015) used simulations to compare a novel proposal, the semantic-lexical-auditory-motor model (SLAM), to an existing account of speech production, the two-step interactive account (TSIA; Foygel & Dell, Journal of Memory and Language, 43:182-216, doi:10.1006/jmla.2000.2716, 2000). This commentary critically examines their assessment of SLAM. The cases in which SLAM outperforms TSIA largely reflect SLAM's ability to (poorly) approximate an existing theory of speech production incorporating two stages of phonological processing (the lexical + postlexical account). The fact that SLAM and TSIA can exhibit equivalent fits to the overall response distribution of a set of aphasic patients is unsurprising, since previous work has shown that overall response distributions do not reliably discriminate theoretical alternatives. Finally, SLAM inherits issues associated with TSIA's assumption of strong feedback between levels of representation. This suggests that SLAM does not represent an advance over existing theories of speech production.

  17. [Spectral features analysis of Pinus massoniana with pest of Dendrolimus punctatus Walker and levels detection].

    Science.gov (United States)

    Xu, Zhang-Hua; Liu, Jian; Yu, Kun-Yong; Gong, Cong-Hong; Xie, Wan-Jun; Tang, Meng-Ya; Lai, Ri-Wen; Li, Zeng-Lu

    2013-02-01

    Taking 51 field measured hyperspectral data with different pest levels in Yanping, Fujian Province as objects, the spectral reflectance and first derivative features of 4 levels of healthy, mild, moderate and severe insect pest were analyzed. On the basis of 7 detecting parameters construction, the pest level detecting models were built. The results showed that (1) the spectral reflectance of Pinus massoniana with pests were significantly lower than that of healthy state, and the higher the pest level, the lower the reflectance; (2) with the increase in pest level, the spectral reflectance curves' "green peak" and "red valley" of Pinus massoniana gradually disappeared, and the red edge was leveleds (3) the pest led to spectral "green peak" red shift, red edge position blue shift, but the changes in "red valley" and near-infrared position were complicated; (4) CARI, RES, REA and REDVI were highly relevant to pest levels, and the correlations between REP, RERVI, RENDVI and pest level were weak; (5) the multiple linear regression model with the variables of the 7 detection parameters could effectively detect the pest levels of Dendrolimus punctatus Walker, with both the estimation rate and accuracy above 0.85.

  18. A Physical Basis for the Symmetries in the Friedmann-Robertson-Walker Metric

    CERN Document Server

    Melia, Fulvio

    2016-01-01

    Modern cosmological theory is based on the Friedmann-Robertson-Walker (FRW) metric. Often written in terms of co-moving coordinates, this well-known solution to Einstein's equations owes its elegant and highly practical formulation to the Cosmological principal and Weyl's postulate, upon which it is founded. But there is physics behind such symmetries, and not all of it has yet been recognized. In this paper, we derive the FRW metric coefficients from the general form of the spherically-symmetric line element, and demonstrate that, because the co-moving frame also happens to be in free fall, the symmetries in FRW are valid only for a medium with zero active mass. In other words, the spacetime of a perfect fluid in cosmology may be correctly written as FRW only when its equation-of-state is rho+3p=0, in terms of the total pressure p and total energy density rho. There is now compelling observational support for this conclusion, including the Alcock-Paczynski test, which shows that only an FRW cosmology with ze...

  19. Chronic Glibenclamide Treatment Attenuates Walker-256 Tumour Growth in Prediabetic Obese Rats

    Directory of Open Access Journals (Sweden)

    Claudinéia Conationi da Silva Franco

    2017-05-01

    Full Text Available Background/Aims: The sulphonylurea glibenclamide (Gli is widely used in the treatment of type 2 diabetes. In addition to its antidiabetic effects, low incidences of certain types of cancer have been observed in Gli-treated diabetic patients. However, the mechanisms underlying this observation remain unclear. The aim of the present work was to evaluate whether obese adult rats that were chronically treated with an antidiabetic drug, glibenclamide, exhibit resistance to rodent breast carcinoma growth. Methods: Neonatal rats were treated with monosodium L-glutamate (MSG to induce prediabetes. Control and MSG groups were treated with Gli (2 mg/kg body weight/day from weaning to 100 days old. After Gli treatment, the control and MSG rats were grafted with Walker-256 tumour cells. After 14 days, grafted rats were euthanized, and tumour weight as well as glucose homeostasis were evaluated. Results: Treatment with Gli normalized tissue insulin sensitivity and glucose tolerance, suppressed fasting hyperinsulinaemia, reduced fat tissue accretion in MSG rats, and attenuated tumour growth by 27% in control and MSG rats. Conclusions: Gli treatment also resulted in a large reduction in the number of PCNA-positive tumour cells. Although treatment did improve the metabolism of pre-diabetic MSG-rats, tumour growth inhibition may be a more direct effect of glibenclamide.

  20. Role of Global Warming in recent Speedup of the Wintertime Pacific Walker Circulation

    Science.gov (United States)

    Li, Xiao-Feng; Li, Jianping; Li, Yun; Yu, Jingjing; Fowler, Hayley; Blenkinsop, Stephen; Ding, Ruiqiang; Zhao, Sen; Zheng, Fei; Feng, Juan; Li, Yanjie; Sun, Cheng

    2017-04-01

    The strengthening of the wintertime Pacific Walker Circulation (PWC) in the past 2-3 decades1-7 is in apparent contradiction to its century-scale weakening under global warming8-10. Although there are several proposed mechanisms, the contribution of global warming to this speedup is still unclear3,11,12. We analyse global SSTs and find the first two EOF modes, a global warming mode (GWM) and an ENSO-like mode (ELM)13, account for over 73% (±17%) of the PWC's post-1976 strengthening trend in winter, its mature phase. We find the GWM weakens the PWC, but the ELM enhances it by over twice as much, with a ratio of -0.37(±0.08):1(±0.23). We further use an atmosphere-only general circulation model to demonstrate the contrasting effects of the GLM and ELM in modulating the PWC. We conclude that global warming is weakening the PWC through the GWM but both modes are needed to resolve the apparent contradiction of recent observations.