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Sample records for water displacement functions

  1. The estimation of oil water displacement functions

    Scientific Electronic Library Online (English)

    G. B., Savioli; E. M., Fernández-Berdaguer.

    2007-09-01

    Full Text Available We introduce an algorithm to solve an inverse problem for a non-linear hyperbolic partial differential equation. It can be used to estimate the oil-fractional flow function from the Buckley-Leverett equation. The direct model is non-linear: the sought for parameter is a function of the solution of t [...] he equation. Traditionally, the estimation of functions requires the election of a fitting parametric model. The algorithm that we develop does not require a predetermined parameter model. Therefore, the estimation problem is carried out over a set of parameters which are functions. The parameter is inferred from measurements of saturation at different spatial points as a function of time. The estimation procedure is carried out linearizing the solution of the direct model with respect to the parameter and then computing the least-squares solution in functional spaces. The sensitivity equations are derived. We test the algorithm with several numerical experiments.

  2. Study about oil displacement efficiency of different position in very high water cut reservoir

    Science.gov (United States)

    Zhong, Yihua; Bing, Shaoxian; Tian, Yan

    2015-03-01

    The key to enhancing oil recovery of very high water cut oilfield lies in analyzing oil displacement efficiency in different position of reservoir, which mainly focus on the analysis of dimensionless cumulative flowing into water volume and oil displacement efficiency distribution. In order to get the oil displacement efficiency distribution characteristics to future analyze influence on oil displacement efficiency by changing well pattern, oil displacement efficiency in different position of homogeneous reservoir is studied by combining the analysis of core displacement experiment with oilfield practice in this paper. Firstly, streamline function and streamline distribution between injection-production well in homogeneous reservoir is researched by the potential function and potential distribution with the five-point well pattern. Secondly, the method of flow distribution on the streamline between the injection-production well is studied according to change law of seepage resistance. Thirdly, dimensionless cumulative flowing into water volume along the streamline is calculated based on the core size to analyze its distribution characteristics about homogeneous reservoir and obtain dimensionless cumulative flowing into water volume at different position of the reservoir matching the core displacement experiment. Finally, the distribution characteristics of oil displacement efficiency are got by statistical analysis for the change of oil displacement efficiency as the dimensionless cumulative flowing into water volume in real oilfield. This study may provide technical measure with oilfield enterprise to enhance the oil recovery of very high water cut oilfield.

  3. Monitoring Changes in Soil Water Content Using Subsurface Displacement

    Science.gov (United States)

    Thrash, C. J.; Miller, S.; Murdoch, L. C.; Germanovich, L. N.; Gates, J. B.; Volkmer, A.; Weinburg, A.

    2013-12-01

    Closing the water balance is important in many research and water resource applications, but it can be difficult to accomplish due to a variety of factors. A new technique that measures vertical displacement of soil in order to estimate the change in mass of water stored in overlying material is being developed. The measurement technique uses an extensometer that functions as a lysimeter, and we refer to the technique as Displacement Extensometry for Lysimetric Terrain Analysis (DELTA). DELTA extensometers are 2-m-long devices deployed by creating a friction fit with intact soil below a cased borehole. The instrument measures small displacements (better than 10 nm resolution) in response to changes of mass in the overlying soil, or other factors. The instrument averages over a region that scales with the depth of installation (the radius of influence is approximately 2x the depth). The spatial averaging of this instrument extends over regions representative of agricultural fields, hydrologic model grid blocks, and small watersheds. Five DELTA extensometers have been deployed at a field site near Clemson, SC at depths of 3, 6, and 9 m within saprolite derived from biotite gneiss. Barometric pressure, precipitation, and soil moisture are being measured along with displacement. Signals from the co-located extensometers are remarkably similar, demonstrating reproducibility of the technique. Rainfall causes soil compression, and at 6 m depth there is approximately 200 nm of compression per 1 mm of rainfall. There is gradual expansion, which ranges from 0.15 to 1.75 ?m/day, following rainfall. The gradual unloading of the soil is interpreted as water loss due to evapotranspiration. Superimposed on the signal are diurnal fluctuations of 0.5 to 1 ?m, which correlate to changes in barometric pressure. Four DELTA extensometers were recently deployed in hard, clayey sediments at two field locations south of Amarillo, TX. The instruments will compliment current research on groundwater recharge in playas. Two other extensometers were deployed in loess at a field site near Holdredge, NE, where they will be used to help characterize water cycling beneath irrigated agriculture. Calibration data has been obtained and the instruments appear to be functioning properly. The preliminary data suggest that the DELTA technique should be applicable in a variety of soil types.

  4. Liquid CO2 displacement of water in a dual-permeability pore network micromodel.

    Science.gov (United States)

    Zhang, Changyong; Oostrom, Mart; Grate, Jay W; Wietsma, Thomas W; Warner, Marvin G

    2011-09-01

    Permeability contrasts exist in multilayer geological formations under consideration for carbon sequestration. To improve our understanding of heterogeneous pore-scale displacements, liquid CO(2) (LCO(2))-water displacement was evaluated in a pore network micromodel with two distinct permeability zones. Due to the low viscosity ratio (logM = -1.1), unstable displacement occurred at all injection rates over 2 orders of magnitude. LCO(2) displaced water only in the high permeability zone at low injection rates with the mechanism shifting from capillary fingering to viscous fingering with increasing flow rate. At high injection rates, LCO(2) displaced water in the low permeability zone with capillary fingering as the dominant mechanism. LCO(2) saturation (S(LCO2)) as a function of injection rate was quantified using fluorescent microscopy. In all experiments, more than 50% of LCO(2) resided in the active flowpaths, and this fraction increased as displacement transitioned from capillary to viscous fingering. A continuum-scale two-phase flow model with independently determined fluid and hydraulic parameters was used to predict S(LCO2) in the dual-permeability field. Agreement with the micromodel experiments was obtained for low injection rates. However, the numerical model does not account for the unstable viscous fingering processes observed experimentally at higher rates and hence overestimated S(LCO2). PMID:21774502

  5. Applying local Green's functions to study the influence of the crustal structure on hydrological loading displacements

    Science.gov (United States)

    Dill, R.; Klemann, V.; Martinec, Z.; Tesauro, M.

    2015-08-01

    The influence of the elastic Earth properties on seasonal or shorter periodic surface deformations due to atmospheric surface pressure and terrestrial water storage variations is usually modeled by applying a local half-space model or an one dimensional spherical Earth model like PREM from which a unique set of elastic load Love numbers, or alternatively, elastic Green's functions are derived. The first model is valid only if load and observer almost coincide, the second model considers only the response of an average Earth structure. However, for surface loads with horizontal scales less than 2500 km2, as for instance, for strong localized hydrological signals associated with heavy precipitation events and river floods, the Earth elastic response becomes very sensitive to inhomogeneities in the Earth crustal structure. We derive a set of local Green's functions defined globally on a 1° × 1° grid for the 3-layer crustal structure TEA12. Local Green's functions show standard deviations of ±12% in the vertical and ±21% in the horizontal directions for distances in the range from 0.1° to 0.5°. By means of Green's function scatter plots, we analyze the dependence of the load response to various crustal rocks and layer thicknesses. The application of local Green's functions instead of a mean global Green's function introduces a variability of 0.5-1.0 mm into the hydrological loading displacements, both in vertical and in horizontal directions. Maximum changes due to the local crustal structures are from -25% to +26% in the vertical and -91% to +55% in the horizontal displacements. In addition, the horizontal displacement can change its direction significantly. The lateral deviations in surface deformation due to local crustal elastic properties are found to be much larger than the differences between various commonly used one-dimensional Earth models.

  6. Cardiorespiratory responses during deep water running with and without horizontal displacement at different cadences

    Directory of Open Access Journals (Sweden)

    A.C. Kanitz

    2014-12-01

    Conclusions: The results indicate that the increase in both cadence and displacement results in significant cardiorespiratory responses as a result of deep water running. This finding is important for adapting exercise prescription to the goals of participants.

  7. Weight Function Method for computations of crack face displacements and stress intensity factors of center cracks

    Directory of Open Access Journals (Sweden)

    Junling Fan

    2015-07-01

    Full Text Available The weight function method provides a powerful and reliable tool for the determination of the stress intensity factor around the crack tip in a linearly elastic cracked solid subjected to arbitrary loading conditions. However, it is difficult to exactly compute the crack face displacement whose partial derivative is responsible for the weight function calculation. In the present paper, only one reference stress intensity factor is used for the purpose of establishing a general expression of the crack face displacement. Then, the generalized and simple expression is applied to calculate the weight function and the stress intensity factor of the center crack configuration. The calculation of the weight function is reduced to the simple integration of the correction function and of the partial derivative of the crack face displacement. It is shown that the present expressions for the computations of the crack face displacement and its partial derivative are in good agreement with their exact solutions.

  8. Displacement as a predictor of functional impairment in tsunami-exposed children.

    Science.gov (United States)

    Lee, Christopher; Du, Ye Beverly; Christina, Desy; Palfrey, Judith; O'Rourke, Edward; Belfer, Myron

    2015-01-01

    Thirty months after the Indian Ocean tsunami of 26 December 2004, thousands of families in Aceh Province, Indonesia, remained in temporary barracks while sanitation conditions and non-governmental organisation support deteriorated. This study sought to determine the factors associated with functional impairment in a sample of 138 displaced and non-displaced Acehnese children. Using multivariate linear regression models, it was found that displacement distance was a consistent predictor of impairment using the Brief Impairment Scale. Exposure to tsunami-related trauma markers was not significantly linked with impairment in the model. Paternal employment was a consistent protective factor for child functioning. These findings suggest that post-disaster displacement and the subsequent familial economic disruption are significant predictors of impaired functioning in children's daily activities. Post-disaster interventions should consider the disruption of familiar environments for families and children when relocating vulnerable populations to avoid deleterious impacts on children's functioning. PMID:25231556

  9. Displacing Androcracy: Cosmopolitan Partnerships in Bapsi Sidhwa’s Water

    OpenAIRE

    Stefano Mercanti

    2011-01-01

    Set against the backdrop of Gandhi’s Freedom Movement, Water pushes the boundaries of India’s male-dominant cultural narratives beyond patriarchal predicaments by questioning the religious tradition and the oppressive constraints imposed on Hindu widows. This paper aims to show how Sidhwa’s characters move toward more caring and life-enhancing scenarios by portraying relationships of mutual support in which human beings give evidence of ‘other’ possible patterns of construction of the self an...

  10. Temporal second-order coherence function for displaced-squeezed thermal states

    CERN Document Server

    Alexanian, Moorad

    2015-01-01

    We calculate the quantum mechanical, temporal second-order coherence function for a single-mode, degenerate parametric amplifier for a system in the Gaussian state, viz., a displaced-squeezed thermal state. The calculation involves first the dynamical generation at time $t$ of the Gaussian state from an initial thermal state and subsequent measurements of two photons a time $\\tau \\geq 0$ apart. The generation of the Gaussian state by the parametric amplifier ensures that the temporal second-order coherence function depends only on $\\tau$, via $\\tau/t$, for given Gaussian state parameters, Gaussian state preparation time $t$, and average number $\\bar{n}$ of thermal photons. It is interesting that the time evolution for displaced thermal states shows a power decay in $\\tau/t$ rather than an exponential one as is the case for general, displaced-squeezed thermal states.

  11. New method to determine initial surface water displacement at tsunami source

    Science.gov (United States)

    Lavrentyev, Mikhail; Romanenko, Alexey; Tatarintsev, Pavel

    2013-04-01

    Friday, March 11, 2011 at 05:46:23 UTC, Japan was struck by an 8.9-magnitude earthquake near its Northeastern coast. This is one of the largest earthquakes that Japan has ever experienced. Tsunami waves swept away houses and cars and caused massive human losses. To predict tsunami wave parameters better and faster, we propose to improve data inversion scheme and achieve the performance gain of data processing. One of the reasons of inaccurate predictions of tsunami parameters is that very little information is available about the initial disturbance of the sea bed at tsunami source. In this paper, we suggest a new way of improving the quality of tsunami source parameters prediction. Modern computational technologies can accurately calculate tsunami wave propagation over the deep ocean provided that the initial displacement (perturbation of the sea bed at tsunami source) is known [4]. Direct geophysical measurements provide the location of an earthquake hypocenter and its magnitude (the released energy evaluation). Among the methods of determination of initial displacement the following ones should be considered. Calculation through the known fault structure and available seismic information. This method is widely used and provides useful information. However, even if the exact knowledge about rock blocks shifts is given, recalculation in terms of sea bed displacement is needed. This results in a certain number of errors. GPS data analysis. This method was developed after the December 2004 event in the Indian Ocean. A good correlation between dry land based GPS sensors and tsunami wave parameters was observed in the particular case of the West coast of Sumatra, Indonesia. This approach is very unique and can hardly been used in other geo locations. Satellite image analysis. The resolution of modern satellite images has dramatically improved. In the future, correct data of sea surface displacement will probably be available in real time, right after a tsunamigenic earthquake. However, today it is not yet possible. Ground-based sea radars. This is an effective tool for direct measurement of tsunami wave. At the same time, the wave is measured at a rather narrow area in front of the radar and does not include information about neighboring parts of the wave. Direct measurement of tsunami wave at deep water [2]. Today, this technology is certainly among the most useful and promising. The DART II® system consists of a seafloor bottom pressure recording (BPR) system, capable of detecting tsunamis as small as 1 cm, and a moored surface buoy for real-time communications. We focus our research on improving the later method, direct measurement of tsunami wave at deep water. We suggest the new way to analyze DART data, modifying the methodology originally proposed by V. Titov. Smaller system of unit sources [3] should be considered to approximate all typical shapes of initial disturbance by several suitable basis functions. To successfully implement it, performance of data analysis should be dramatically improved. This could be done by using a signal orthogonalization procedure for considered system of unit sources and calculation of Fourier coefficients of the measured time series with respect to orthogonal basis. The approach suggested was used as a part of computerized workstation for tsunami hazard monitoring [5-6]. National Oceanic and Atmospheric Administration Center for Tsunami Research. URL: http://nctr.pmel.noaa.gov/honshu20110311/ National Data Buoy Center. URL: http://www.ndbc.noaa.gov/dart.shtml National Oceanic and Atmospheric Administration Center for Tsunami Research. URL: http://sift.pmel.noaa.gov/thredds/dodsC/uncompressed/ National Oceanic and Atmospheric Administration Center for Tsunami Research. URL: http://nctr.pmel.noaa.gov/model.html Alexey Romanenko, Mikhail Lavrentiev-jr, Vasily Titov, "Modern Architecture for Tsunami Hazard Mitigation" // Asia Oceania Geosciences Society (AOGS-2012), ISBN 978-981-07-2049-0 Mikhail Lavrentiev-jr, Andrey Marchuk, Alexey Romanenko, Konstantin Simonov, and Vasiliy T

  12. Resolution Effects on the Mean Square Displacement as Obtained by the Self-Distribution-Function Procedure

    International Nuclear Information System (INIS)

    In the present contribution, a procedure for molecular motion characterization based on the evaluation of the Mean Square Displacement (MSD), through the Self-Distribution Function (SDF), is presented. It is shown how MSD, which represents an important observable for the characterization of dynamical properties, can be decomposed into different partial contributions associated to system dynamical processes within a specific spatial scale. It is also shown how the SDF procedure allows us to evaluate both total MSD and partial MSDs through total and partial SDFs. As a result, total MSD is the weighed sum of partial MSDs in which the weights are obtained by the fitting procedure of measured Elastic Incoherent Neutron Scattering (EINS) intensity. We apply SDF procedure to data collected,by IN13, IN10 and IN4 spectrometers (Institute Laue Langevin), on aqueous mixtures of two homologous disaccharides (sucrose and trehalose) and on dry and hydrated (H2O and D2O) lysozyme with and without disaccharides. It emerges that the hydrogen bond imposed network of the water-trehalose mixture appears to be stronger with respect to that of the water-sucrose mixture. This result can justify the higher bioprotectant effectiveness of trehalose. Furthermore, it emerges that partial MSDs of sucrose and trehalose are equivalent in the low Q domain (0÷1.7) ??1 whereas they are different in the high Q domain (1.7÷4) ??1. This suggests that the higher structure sensitivity of sucrose should be related to the small spatial observation windows. Moreover, the role of the instrumental resolution in EINS is considered. The nature of the dynamical transition is highlighted and it is shown that it occurs when the system relaxation time becomes shorter than the instrumental energy time. Finally, the bioprotectants effect on protein dynamics and the amplitude of vibrations in lysozyme are presented.

  13. Computing the dielectric constant of liquid water at constant dielectric displacement

    CERN Document Server

    Zhang, Chao

    2015-01-01

    The static dielectric constant of liquid water is computed using classical force field based molecular dynamics simulation at fixed electric displacement D. The method to constrain the electric displacement is the finite temperature classical variant of the constant-D method developed by Stengel, Spaldin and Vanderbilt (Nat. Phys. 2009, 5: 304). There is also a modification of this scheme imposing fixed values of the macroscopic field E. The method is applied to the popular SPC/E model of liquid water. We compare four different estimates of the dielectric constant, two obtained from fluctuations of the polarization at D = 0 and E = 0 and two from the variation of polarization with finite D and E. It is found that all four estimates agree when properly converged. The computational effort to achieve convergence varies however, with constant D calculations being substantially more efficient. We attribute this difference to the much shorter relaxation time of longitudinal polarization compared to transverse polar...

  14. Constant load and constant displacement stress corrosion in simulated water reactor environments

    International Nuclear Information System (INIS)

    The stress corrosion behaviour of selected water reactor constructional materials, as determined by constant load or constant displacement test techniques, is reviewed. Experimental results obtained using a very wide range of conditions have been collected in a form for easy reference. A discussion is given of some apparent trends in these data. The possible reasons for these trends are considered together with a discussion of how the observed discrepancies may be resolved. (author)

  15. Three-dimensional point spread function characterization of a radially displaced scatterer

    Science.gov (United States)

    Majumder, Uttam K.; Temple, Michael A.; Minardi, Michael J.; Zelnio, Edmund G.

    2007-04-01

    For synthetic aperture radar (SAR) systems utilizing a circular aperture for target recognition, it is important to know how a target's point spread function (PSF) behaves as a function of various radar functional parameters and target positional changes that may occur during data collection. The purpose of this research is characterizing the three dimensional (3D) point spread function (3D PSF) behavior of a radially displaced point scatterer for circular synthetic aperture radar (CSAR). For an automatic target recognition (ATR) systems requiring target identification with a high degree of confidence, CSAR processing represents a viable alternative given it can produce images with resolution less than a wavelength. With very large CSAR apertures (90°r or more) three dimensional imaging is possible with a single phase center and a single pass. Using a backprojection image formation process, point target PSF responses are generated at various target locations at a given radar bandwidth, depression angle and full 360°r CSAR apertures. Consistent with previous studies, the 3D PSF for a point target located at the image center is cone shaped and serves as the basis for comparing and characterizing the 3D PSFs for radially displaced scatterers. For radially displaced point target, simulated results show 3D PSF response is asymmetric and tends to become an elliptic shape.

  16. A computational chemical study of penetration and displacement of water films near mineral surfaces

    Directory of Open Access Journals (Sweden)

    Larter Steve R

    2001-08-01

    Full Text Available A series of molecular dynamics simulations have been performed on organic–water mixtures near mineral surfaces. These simulations show that, in contrast to apolar compounds, small polar organic compounds such as phenols can penetrate through thin water films to adsorb on these mineral surfaces. Furthermore, additional simulations involving demixing of an organic–water mixture near a surfactant-covered mineral surface demonstrate that even low concentrations of adsorbed polar compounds can induce major changes in mineral surface wettability, allowing sorption of apolar molecules. This strongly supports a two-stage adsorption mechanism for organic solutes, involving initial migration of small polar organic molecules to the mineral surface followed by water film displacement due to co-adsorption of the more apolar organic compounds, thus converting an initial water-wet mineral system to an organic-covered surface. This has profound implications for studies of petroleum reservoir diagenesis and wettability changes.

  17. Near-infrared studies of glucose and sucrose in aqueous solutions: water displacement effect and red shift in water absorption from water-solute interaction

    CERN Document Server

    Jung, Youngeui

    2013-01-01

    We use near infrared spectroscopy to obtain concentration dependent glucose absorption spectra in their aqueous solutions in the near-infrared range (3800 - 7500 cm^{-1}). We introduce a new method to obtain reliable glucose absorption bands from aqueous glucose solutions without measuring the water displacement coefficients of glucose separately. Additionally, we are able to extract the water displacement coefficients of glucose, and this may give a new general method using spectroscopy techniques applicable to other water soluble materials. We also observe red shifts in the absorption bands of water in the hydration shell around solute molecules, which comes from contribution of the interacting water molecules around the glucose molecules in solutions. The intensity of the red shift get larger as the concentration increases, which indicates that as the concentration increases more water molecules are involved in the interaction. However, the red shift in frequency does not seem to depend significantly on th...

  18. Measuring and Modeling the Displacement of Connate Water in Chalk Core Plugs during Water Injection

    DEFF Research Database (Denmark)

    Korsbech, Uffe C C; Aage, Helle Karina

    2006-01-01

    The movement of connate water spiked with gamma emitting 22Na was studied during laboratory water flooding of oil saturated chalk from a North Sea oil reservoir. Using a one dimensional gamma monitoring technique is was observed that connate water is piled-up at the front of the injection water and forms a mixed water bank with almost 100% connate water in the front behind which a gradual transition to pure injection water occurs. This result underpins log interpretations from waterflooded chalk reservoirs. An ad hoc model was set up by use of the results, and the process was examined theoretically at a larger scale.

  19. The Energy and Water Emergency Module; A containerized solution for meeting the energy and water needs in protracted displacement situations

    DEFF Research Database (Denmark)

    Nerini, Francesco Fuso; Valentini, Francesco

    2015-01-01

    The world has faced many natural and man-made disasters in the past few years, resulting in millions of people living in temporary camps across the globe. The energy and clean water needs of the relief operators in such emergency situations are primarily satisfied by diesel engine based generators and importing clean water to the site, in certain cases even for several years after the emergency. This approach results in problems such as low security of supply and high costs. Especially targeting the prolonged displacement situations, this paper presents an alternative solution – the Energy and Water Emergency Module. The proposed solution aims towards reducing the dependency on fossil fuel in prolonged emergency situations to a minimum while including local energy sources in the energy supply in a flexible and reliable way. The proposed module is built in a standard 20 ft container, and encompasses hybrid generation from solar, wind and biomass, with the possibility of using fossil sources too thanks to a dual fuel gas engine. The module can work both in grid connected and stand-alone mode. In addition the module includes a water purification unit to meet the water needs of displaced population. A demonstration unit was assembled at the Royal Institute of Technology in Stockholm during the year 2012 as a ‘concept proof’, and is now being tested and optimized for future deployment on the field. Preliminary testing and modelling shows that the proposed solution can reliably support emergency situations, and is already cost competitive with the current water and energy supply solutions for emergency situations. © 2015 Elsevier Ltd. All rights reserved.

  20. An accurate higher order displacement model with shear and normal deformations effects for functionally graded plates

    Energy Technology Data Exchange (ETDEWEB)

    Jha, D.K., E-mail: dkjha@barc.gov.in [Civil Engineering Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Kant, Tarun [Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India); Srinivas, K. [Civil Engineering Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Singh, R.K. [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2013-12-15

    Highlights: • We model through-thickness variation of material properties in functionally graded (FG) plates. • Effect of material grading index on deformations, stresses and natural frequency of FG plates is studied. • Effect of higher order terms in displacement models is studied for plate statics. • The benchmark solutions for the static analysis and free vibration of thick FG plates are presented. -- Abstract: Functionally graded materials (FGMs) are the potential candidates under consideration for designing the first wall of fusion reactors with a view to make best use of potential properties of available materials under severe thermo-mechanical loading conditions. A higher order shear and normal deformations plate theory is employed for stress and free vibration analyses of functionally graded (FG) elastic, rectangular, and simply (diaphragm) supported plates. Although FGMs are highly heterogeneous in nature, they are generally idealized as continua with mechanical properties changing smoothly with respect to spatial coordinates. The material properties of FG plates are assumed here to vary through thickness of plate in a continuous manner. Young's modulii and material densities are considered to be varying continuously in thickness direction according to volume fraction of constituents which are mathematically modeled here as exponential and power law functions. The effects of variation of material properties in terms of material gradation index on deformations, stresses and natural frequency of FG plates are investigated. The accuracy of present numerical solutions has been established with respect to exact three-dimensional (3D) elasticity solutions and the other models’ solutions available in literature.

  1. Water displacement by sewer infrastructure in the Grote Nete catchment, Belgium, and its hydrological regime effects

    Directory of Open Access Journals (Sweden)

    D. Vrebos

    2013-06-01

    Full Text Available Urbanization and especially impervious areas, in combination with wastewater treatment infrastructure, can exert several pressures on the hydrological cycle. These pressures were studied for the Grote Nete catchment in Belgium (8.18% impervious area and 3.89% effective impervious area, based on a combination of empirical and model-based approaches. The effective impervious area, combined with the extent of the wastewater collection regions which do not coincide with the natural catchment boundaries, was used as an indicator for the urbanization pressure. Our study revealed changes in the total upstream areas of the subcatchments between ?16% and +3%, and in upstream impervious areas between ?99% and +64%. These changes lead to important inter-catchment water transfers. Based on simulations with a physically-based and spatially-distributed hydrological catchment model, profound impacts of effective impervious area on infiltration and runoff were found. The model results show that the changes in impervious areas and related water displacements in and between catchments due to the installation of the wastewater treatment infrastructure severely impacted low flows, peak flows and seasonal trends. They moreover show that it is difficult, but of utmost importance, to incorporate these pressures and artificial processes in an accurate way during the development of hydrological models for urbanized catchments.

  2. Top end support for water displacement rod guides of pressurized water reactor

    International Nuclear Information System (INIS)

    This patent describes a top end support for rod guides disposed in closely spaced, parallel axial relationship in an inner barrel assembly of a pressurized water reactor vessel. The inner barrel assembly occupies a central portion of the vessel and is of a vertical height extending from a first plate of lower elevation to a second plate of higher elevation within the vessel. Each of the rod guides has a thin sidewall portion of elongated configuration and of an axial length corresponding substantially to the vertical height of the inner barrel assembly and having a generally square cross-section. Each rod guide accommodating in axial, sliding relationship therewithin a respectively associated cluster of elongated rods interconnected to extend in parallel axial relationship

  3. Pore-scale simulation of liquid CO2 displacement of water using a two-phase lattice Boltzmann model

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Haihu; Valocchi, Albert J.; Werth, Charles J.; Kang, Oinjun; Oostrom, Martinus

    2014-11-01

    A lattice Boltzmann color-fluid model, which was recently proposed by Liu et al. [H. Liu, A.J. Valocchi, and Q. Kang. Three-dimensional lattice Boltzmann model for immiscible two-phase flow simulations. Phys. Rev. E, 85:046309, 2012.] based on a concept of continuum surface force, is improved to simulate immiscible two-phase flows in porous media. The new improvements allow the model to account for different kinematic viscosities of both fluids and to model fluid-solid interactions. The capability and accuracy of this model is first validated by two benchmark tests: a layered two-phase flow with a viscosity ratio, and a dynamic capillary intrusion. This model is then used to simulate liquid CO2 (LCO2) displacing water in a dual-permeability pore network. The extent and behavior of LCO2 preferential flow (i.e., fingering) is found to depend on the capillary number (Ca), and three different displacement patterns observed in previous micromodel experiments are reproduced. The predicted variation of LCO2 saturation with Ca, as well as variation of specific interfacial length with LCO2 saturation, are both in good agreement with the experimental observations. To understand the effect of heterogeneity on pore-scale displacement, we also simulate LCO2 displacing water in a randomly heterogeneous pore network, which has the same size and porosity as the dual-permeability pore network. In comparison to the dual-permeability case, the transition from capillary fingering to viscous fingering occurs at a higher Ca, and LCO2 saturation is higher at low Ca but lower at high Ca. In either pore network, the LCO2-water specific interfacial length is found to obey a power-law dependence on LCO2 saturation.

  4. Invasion of an asexual American water flea clone throughout Africa and rapid displacement of a native sibling species.

    Science.gov (United States)

    Mergeay, Joachim; Verschuren, Dirk; De Meester, Luc

    2006-11-22

    The huge ecological and economic impact of biological invasions creates an urgent need for knowledge of traits that make invading species successful and factors helping indigenous populations to resist displacement by invading species or genotypes. High genetic diversity is generally considered to be advantageous in both processes. Combined with sex, it allows rapid evolution and adaptation to changing environments. We combined paleogenetic analysis with continent-wide survey of genetic diversity at nuclear and mitochondrial loci to reconstruct the invasion history of a single asexual American water flea clone (hybrid Daphnia pulexxDaphnia pulicaria) in Africa. Within 60 years of the original introduction of this invader, it displaced the genetically diverse, sexual population of native D. pulex in Lake Naivasha (Kenya), despite a formidable numerical advantage of the local population and continuous replenishment from a large dormant egg bank. Currently, the invading clone has spread throughout the range of native African D. pulex, where it appears to be the only occurring genotype. The absence of genetic variation did not hamper either the continent-wide establishment of this exotic lineage or the effective displacement of an indigenous and genetically diverse sibling species. PMID:17015310

  5. A forcefield with discrete displaceable waters and desolvation entropy for hydrated ligand docking

    OpenAIRE

    Forli, Stefano; Olson, Arthur J.

    2012-01-01

    In modeling ligand-protein interactions, the representation and role of water is of great importance. We introduce a forcefield and hydration docking method that enables the automated prediction of waters mediating the binding of ligands with target proteins. The method presumes no prior knowledge of the apo or holo protein hydration state, and is potentially useful in the process of structure-based drug discovery. The hydration forcefield accounts for the entropic and enthalpic contributions...

  6. Effective electron displacements: A tool for time-dependent density functional theory computational spectroscopy

    International Nuclear Information System (INIS)

    We extend our previous definition of the metric ?r for electronic excitations in the framework of the time-dependent density functional theory [C. A. Guido, P. Cortona, B. Mennucci, and C. Adamo, J. Chem. Theory Comput. 9, 3118 (2013)], by including a measure of the difference of electronic position variances in passing from occupied to virtual orbitals. This new definition, called ?, permits applications in those situations where the ?r-index is not helpful: transitions in centrosymmetric systems and Rydberg excitations. The ?-metric is then extended by using the Natural Transition Orbitals, thus providing an intuitive picture of how locally the electron density changes during the electronic transitions. Furthermore, the ? values give insight about the functional performances in reproducing different type of transitions, and allow one to define a “confidence radius” for GGA and hybrid functionals

  7. Micromodel Study of Influence of Pore Geometry on Water-Oil Displacement with and without Surfactant

    Science.gov (United States)

    Yin, X.; Xu, W.; Ok, J.; Neeves, K.

    2012-12-01

    Using oil-wet Polydimethylsiloxane (PDMS) based microfluidic micromodels, we studied the effect of pore geometry on water-oil drainage efficiency. The porosity and permeability of micromodels are 0.19 and about 200md, respectively; the size of the micromodels is 3 cm by 3 mm, with the longer dimension aligned with the flow direction. The pore geometries compared include a random network of uniformly sized channels (6 ?m), a network with a channel size distribution (4-8 ?m), and a geometry with large vugs (200-300 ?m) embedded in a network of uniformly sized channels (8 ?m); the last one was designed to simulate the vuggy texture of oil-wet carbonate rocks. Regular patterns with periodically arranged squares and hexagons were also made. Water saturations were measured at the point of water breakthrough as well as at intervals of 0.5 pore volume injection up to a total of three pore volumes. We found that both pore size distribution and vugs decreased the drainage efficiency. In addition, while application of surfactant (5000 ppm ethoxylated alcohol) increased the drainage efficiency in all geometries by increasing the Capillary number, the gain was less for geometries with vugs. From videos, we noted withdrawal of non-wetting fluid from channels while the vugs were filled due to disparity in the capillary pressure. The preference for the non-wetting fluid to fill the vugs caused early breakthrough and trapping of the wetting fluid that is difficult to remove even at increased Capillary numbers.

  8. Complications and functional outcome after internal fixation of dorsally displaced distal radial fractures

    DEFF Research Database (Denmark)

    Bove, Jeppe; Viberg, Bjarke; Greisen, Pernille; Hansen, Jan Schultz

    2010-01-01

    Background: Recently there has been an increasing interest in open reduction and internal fixation of distal radius fractures. Even so further studies are still needed. Purpose: To document the functional outcome and identify complica- tions among patients treated with a volar locking plate (DVR-locking plate, DePuy Orthopaedics) newly introduced in our department. Methods: The study was designed as a historical cohort study. 37 females and 6 males with a mean (CI) age of 72,6 (69,5-75,6) were i...

  9. The Energy and Water Emergency Module; A containerized solution for meeting the energy and water needs in protracted displacement situations

    DEFF Research Database (Denmark)

    Nerini, Francesco Fuso; Valentini, Francesco; Modi, Anish; Upadhyay, Govinda; Abeysekera, Muditha; Salehin, Sayedus; Appleyard, Eduardo

    2015-01-01

    The world has faced many natural and man-made disasters in the past few years, resulting in millions of people living in temporary camps across the globe. The energy and clean water needs of the relief operators in such emergency situations are primarily satisfied by diesel engine based generators and importing clean water to the site, in certain cases even for several years after the emergency. This approach results in problems such as low security of supply and high costs. Especially targeting...

  10. Assessing Climate Change Impacts on Water Resources and Colorado Agriculture Using an Equilibrium Displacement Mathematical Programming Model

    Directory of Open Access Journals (Sweden)

    Eihab Fathelrahman

    2014-06-01

    Full Text Available This research models selected impacts of climate change on Colorado agriculture several decades in the future, using an Economic Displacement Mathematical Programming model. The agricultural economy in Colorado is dominated by livestock, which accounts for 67% of total receipts. Crops, including feed grains and forages, account for the remainder. Most agriculture is based on irrigated production, which depends on both groundwater, especially from the Ogallala aquifer, and surface water that comes from runoff derived from snowpack in the Rocky Mountains. The analysis is composed of a Base simulation, designed to represent selected features of the agricultural economy several decades in the future, and then three alternative climatic scenarios are run. The Base starts with a reduction in agricultural water by 10.3% from increased municipal and industrial water demand, and assumes a 75% increase in corn extracted-ethanol production. From this, the first simulation (S1 reduces agricultural water availability by a further 14.0%, for a combined decrease of 24.3%, due to climatic factors and related groundwater depletion. The second simulation (S2-WET describes wet year conditions, which negatively affect yields of irrigated corn and milking cows, but improves yields for important crops such as non-irrigated wheat and forages. In contrast, the third simulation (S3-DRY describes a drought year, which leads to reduced dairy output and reduced corn and wheat. Consumer and producer surplus losses are approximately $10 million in this simulation. The simulation results also demonstrate the importance of the modeling trade when studying climate change in a small open economy, and of linking crop and livestock activities to quantify overall sector effects. This model has not taken into account farmers’ adaptation strategies, which would reduce the climate impact on yields, nor has it reflected climate-induced shifts in planting decisions and production practices that have environmental impacts or higher costs. It also focuses on a comparative statics approach to the analysis in order to identify several key effects of changes in water availability and yields, without having a large number of perhaps confounding assumptions.

  11. Immiscible displacement of oil by water in a microchannel: asymmetric flow behavior and nonlinear stability analysis of core-annular flow.

    Science.gov (United States)

    Foroughi, Hooman; Abbasi, Alireza; Das, Kausik S; Kawaji, Masahiro

    2012-02-01

    The immiscible displacement of oil by water in a circular microchannel was investigated. A fused silica microchannel with an inner diameter of 250 ?m and a length of 7 cm was initially filled with a viscous silicone oil. Only water then was injected into the channel. We describe our flow observations based on the two-dimensional images captured in the middle of the channel. The water finger displaced the oil and left an oil film on the channel wall. While the oil was being displaced at the core, the flow resistance decreased, which resulted in increases in water flow rate and inertia. Eventually, the water finger reached the channel exit and formed a core-annular flow pattern. The wavelength of the waves formed at the oil-water interface also increased with the increase in inertia. The initially symmetric interfacial waves became asymmetric with time. Also, the water core shifted from the center of the channel and left a thinner oil film on one side of the microchannel. Under all flow rates tested in this study, as long as the water was continuously injected, the water core was stable and no breakup into droplets was observed. We also discuss the flow stability based on nonlinear and linear stability analyses performed on the core-annular flow. Compared to the linear analysis, which ignores the inertia effects, the nonlinear analysis, which includes the inertia effects, predicts longer interfacial wavelengths by a factor of 1/sqrt[1-a(o)/2(We(w) + We(o)a(o)(2)/1-a(o)(2))] where We(w) and We(o) are the Weber numbers of the water and the oil phases, respectively, and a(o) is the unperturbed water core radius made dimensionless by the channel radius. PMID:22463319

  12. Indicator displacement assay for cholesterol electrochemical sensing using a calix[6]arene functionalized graphene-modified electrode.

    Science.gov (United States)

    Yang, Long; Zhao, Hui; Li, Yucong; Ran, Xin; Deng, Guogang; Zhang, Yanqiong; Ye, Hanzhang; Zhao, Genfu; Li, Can-Peng

    2016-01-01

    A novel electrochemical method has been developed towards cholesterol detection based on competitive host-guest interaction by selecting methylene blue (MB) and calix[6]arene functionalized graphene (CX6-Gra) as the "reporter pair". In the presence of cholesterol, the MB molecules are displaced by cholesterol in the CX6-Gra.MB complex, leading to a "switch off" electrochemical response. A linear response range of 0.50 to 50.00 ?M for cholesterol with a low detection limit of 0.20 ?M (S/N = 3) was obtained by using the proposed method. This method could be successfully utilized to detect cholesterol in serum samples, and may be expanded to the analysis of other non-electroactive species. Besides, the host-guest interaction between cholesterol and CX6 was studied by molecular modeling calculations, which revealed that the complexation could reduce the energy of the system and the complex of a 1?:?1 host-guest stoichiometry had the lowest binding free energy of -8.01 kcal mol(-1). In addition, the constructed electrochemical sensing platform is important as it does not use any enzyme or antibody for the detection of cholesterol efficiently and selectively over common interfering species. PMID:26626104

  13. The 'wet mind': water and functional neuroimaging

    International Nuclear Information System (INIS)

    Functional neuroimaging has emerged as an important approach to study the brain and the mind. Surprisingly, although they are based on radically different physical approaches both positron emission tomography (PET) and magnetic resonance imaging (MRI) make brain activation imaging possible through measurements involving water molecules. So far, PET and MRI functional imaging have relied on the principle that neuronal activation and blood flow are coupled through metabolism. However, a new paradigm has emerged to look at brain activity through the observation with MRI of the molecular diffusion of water. In contrast with the former approaches diffusion MRI has the potential to reveal changes in the intrinsic water physical properties during brain activation, which could be more intimately linked to the neuronal activation mechanisms and lead to an improved spatial and temporal resolution. However, this link has yet to be fully confirmed and understood. To shed light on the possible relationship between water and brain activation, this introductory paper reviews the most recent data on the physical properties of water and on the status of water in biological tissues, and evaluates their relevance to brain diffusion MRI. The biophysical mechanisms of brain activation are then reassessed to reveal their intimacy with the physical properties of water, which may come to be regarded as the 'molecule of the mind'. (invited topical review)

  14. Design and Realization of a Three Degrees of Freedom Displacement Measurement System Composed of Hall Sensors Based on Magnetic Field Fitting by an Elliptic Function

    Science.gov (United States)

    Zhao, Bo; Wang, Lei; Tan, Jiu-Bin

    2015-01-01

    This paper presents the design and realization of a three degrees of freedom (DOFs) displacement measurement system composed of Hall sensors, which is built for the XY?z displacement measurement of the short stroke stage of the reticle stage of lithography. The measurement system consists of three pairs of permanent magnets mounted on the same plane on the short stroke stage along the Y, Y, X directions, and three single axis Hall sensors correspondingly mounted on the frame of the reticle stage. The emphasis is placed on the decoupling and magnetic field fitting of the three DOFs measurement system. The model of the measurement system is illustrated, and the XY positions and ?Z rotation of the short stroke stage can be obtained by decoupling the sensor outputs. A magnetic field fitting by an elliptic function-based compensation method is proposed. The practical field intensity of a permanent magnet at a certain plane height can be substituted for the output voltage of a Hall sensors, which can be expressed by the elliptic function through experimental data as the crucial issue to calculate the three DOFs displacement. Experimental results of the Hall sensor displacement measurement system are presented to validate the proposed three DOFs measurement system. PMID:26370993

  15. Design and Realization of a Three Degrees of Freedom Displacement Measurement System Composed of Hall Sensors Based on Magnetic Field Fitting by an Elliptic Function

    Directory of Open Access Journals (Sweden)

    Bo Zhao

    2015-09-01

    Full Text Available This paper presents the design and realization of a three degrees of freedom (DOFs displacement measurement system composed of Hall sensors, which is built for the XY?z displacement measurement of the short stroke stage of the reticle stage of lithography. The measurement system consists of three pairs of permanent magnets mounted on the same plane on the short stroke stage along the Y, Y, X directions, and three single axis Hall sensors correspondingly mounted on the frame of the reticle stage. The emphasis is placed on the decoupling and magnetic field fitting of the three DOFs measurement system. The model of the measurement system is illustrated, and the XY positions and ?Z rotation of the short stroke stage can be obtained by decoupling the sensor outputs. A magnetic field fitting by an elliptic function-based compensation method is proposed. The practical field intensity of a permanent magnet at a certain plane height can be substituted for the output voltage of a Hall sensors, which can be expressed by the elliptic function through experimental data as the crucial issue to calculate the three DOFs displacement. Experimental results of the Hall sensor displacement measurement system are presented to validate the proposed three DOFs measurement system.

  16. Assessment of Volume Measurement of Breast Cancer-Related Lymphedema by Three Methods: Circumference Measurement, Water Displacement, and Dual Energy X-Ray Absorptiometry

    DEFF Research Database (Denmark)

    Gjørup, Caroline; Zerahn, B.; Hendel, Helle Westergren

    2010-01-01

    Background: Following treatment for breast cancer 12%-60% develop breast cancer-related lymphedema (BCRL). There are several ways of assessing BCRL. Circumference measurement (CM) and water displacement (WD) for volume measurements (VM) are frequently used methods in practice and research, respectively. The aim of this study was to evaluate CM and WD for VM of the BCRL arm and the contralateral arm, comparing the results with regional dual energy X-ray absorptiometry (DXA). Methods and Results: ...

  17. Effects of Buoyancy Forces on Immiscible Water/Oil Displacements in a Vertically Oriented Porous Medium Effets des facteurs de flottabilité sur les déplacements non-miscibles eau/huile dans un milieu poreux vertical

    OpenAIRE

    Thirunavu S. R.; Neale G. H.

    2006-01-01

    The effects of buoyancy forces on liquid-liquid displacement processes occurring in porous media are important in a variety of practical situations, in particular during the displacement of oil from partially-depleted underground reservoirs by means of aqueous solutions. Most previous studies involving the visualization of water/oil displacements in porous media have been undertaken in horizontal two-dimensional porous medium cells. The objective of the present work was to determine the effec...

  18. Triplet correlation functions in liquid water

    Science.gov (United States)

    Dhabal, Debdas; Singh, Murari; Wikfeldt, Kjartan Thor; Chakravarty, Charusita

    2014-11-01

    Triplet correlations have been shown to play a crucial role in the transformation of simple liquids to anomalous tetrahedral fluids [M. Singh, D. Dhabal, A. H. Nguyen, V. Molinero, and C. Chakravarty, Phys. Rev. Lett. 112, 147801 (2014)]. Here we examine triplet correlation functions for water, arguably the most important tetrahedral liquid, under ambient conditions, using configurational ensembles derived from molecular dynamics (MD) simulations and reverse Monte Carlo (RMC) datasets fitted to experimental scattering data. Four different RMC data sets with widely varying hydrogen-bond topologies fitted to neutron and x-ray scattering data are considered [K. T. Wikfeldt, M. Leetmaa, M. P. Ljungberg, A. Nilsson, and L. G. M. Pettersson, J. Phys. Chem. B 113, 6246 (2009)]. Molecular dynamics simulations are performed for two rigid-body effective pair potentials (SPC/E and TIP4P/2005) and the monatomic water (mW) model. Triplet correlation functions are compared with other structural measures for tetrahedrality, such as the O-O-O angular distribution function and the local tetrahedral order distributions. In contrast to the pair correlation functions, which are identical for all the RMC ensembles, the O-O-O triplet correlation function can discriminate between ensembles with different degrees of tetrahedral network formation with the maximally symmetric, tetrahedral SYM dataset displaying distinct signatures of tetrahedrality similar to those obtained from atomistic simulations of the SPC/E model. Triplet correlations from the RMC datasets conform closely to the Kirkwood superposition approximation, while those from MD simulations show deviations within the first two neighbour shells. The possibilities for experimental estimation of triplet correlations of water and other tetrahedral liquids are discussed.

  19. Displaced Supersymmetry

    CERN Document Server

    Graham, Peter W; Rajendran, Surjeet; Saraswat, Prashant

    2012-01-01

    The apparent absence of light superpartners at the LHC strongly constrains the viability of the MSSM as a solution to the hierarchy problem. These constraints can be significantly alleviated by R-parity violation (RPV). Bilinear R-parity violation, with the single operator L H_u, does not require any special flavor structure and can be naturally embedded in a GUT while avoiding constraints from proton decay (unlike baryon-number-violating RPV). The LSP in this scenario can be naturally long-lived, giving rise to displaced vertices. Many collider searches, particularly those selecting b-jets or leptons, are insensitive to events with such detector-scale displaced decays owing to cuts on track quality and impact parameter. We demonstrate that for decay lengths in the window ~1-1000 mm, constraints on superpartner masses can be as low as ~450 GeV for squarks and ~40 GeV for LSPs. In some parts of parameter space light LSPs can dominate the Higgs decay width, hiding the Higgs from existing searches. This framewor...

  20. Functionalization of carbon nanotubes by water plasma

    International Nuclear Information System (INIS)

    Multiwall carbon nanotubes grown by plasma enhanced chemical vapour deposition were functionalized by H2O plasma treatment. Through a controlled functionalization process of the carbon nanotubes (CNTs) we were able to modify and tune their chemical reactivity, expanding the range of potential applications in the field of energy and environment. In particular, different oxygen groups were attached to the surfaces of the nanotubes (e.g. carboxyl, hydroxyl and carbonyl), which changed their physicochemical properties. In order to optimize the main operational parameters of the H2O plasma treatment, pressure and power, a Box–Wilson experimental design was adopted. Analysis of the morphology, electrochemical properties and functional groups attached to the surfaces of the CNTs allowed us to determine which treatment conditions were suitable for different applications. After water plasma treatment the specific capacitance of the nanotubes increased from 23 up to 68 F g?1 at a scan rate of 10 mV s?1. (paper)

  1. Functionalization of carbon nanotubes by water plasma.

    Science.gov (United States)

    Hussain, S; Amade, R; Jover, E; Bertran, E

    2012-09-28

    Multiwall carbon nanotubes grown by plasma enhanced chemical vapour deposition were functionalized by H(2)O plasma treatment. Through a controlled functionalization process of the carbon nanotubes (CNTs) we were able to modify and tune their chemical reactivity, expanding the range of potential applications in the field of energy and environment. In particular, different oxygen groups were attached to the surfaces of the nanotubes (e.g. carboxyl, hydroxyl and carbonyl), which changed their physicochemical properties. In order to optimize the main operational parameters of the H(2)O plasma treatment, pressure and power, a Box-Wilson experimental design was adopted. Analysis of the morphology, electrochemical properties and functional groups attached to the surfaces of the CNTs allowed us to determine which treatment conditions were suitable for different applications. After water plasma treatment the specific capacitance of the nanotubes increased from 23 up to 68 F g(-1) at a scan rate of 10 mV s(-1). PMID:22947598

  2. Short-range ordering by displacement of Tl and O atoms in Tl2CaBa2Cu2O8 studied by pair distribution function and rietveld analysis

    International Nuclear Information System (INIS)

    Atomic pair distribution function analysis has demonstrated displacements of Tl and O atoms within the Tl-O layers with short-range ordering of lower symmetry than the crystallographic lattice. Two models have been proposed for these displacements. Rietveld analysis neither confirms not contradicts these models. Temperature-dependent PDF measurements show changes in local structure correlating with temperature

  3. Assessment of functional displacement of bone marrow by osteoplastic metastases from prostatic carcinoma with bone marrow scintigraphy

    International Nuclear Information System (INIS)

    The detailed examination of the skeleton in prostate cancer has become more critical since surgical treatment requires the non-evidence of bone metastases. The data of 30 patients have been evaluated. All patients had a bone scan and a bone marrow scintigraphy with [99mTc[-anti-NCA95. In this study we compared the degree of bone marrow displacement with the extent of metastatic deposits identified on the bone scan. Six patients showing the criterias of a superscan (maximal avidity of the osteotrope radiatracer) had as a correlate a complete displacement of the hematopoesis in the bone marrow scintigraphy and an increased activity in liver and spleen. The degree of the peripheral extension correlated strongly with the decrease of the haemoglobin in blood samples. The grading was based upon the number of metastatic deposits identified on the scan (0=no metastases; 1?6 metastases; 2=multiple metastases; 3=superscan). In 28 of 30 patients (93%) we found corresponding results in both the bone scan and the bone marrow scintigraphy. The bone marrow scintigraphy is a sensitive method in the detection of metastatic disease and gives additional information about the extent of bone marrow displacement by osteoplastic metastases. (orig.)

  4. The Van Hove Scattering Function for Water

    International Nuclear Information System (INIS)

    Measurements, using the Chalk River rotating crystal spectrometer at a resolution of 2 x 10-4 eV, of the energy distributions of neutrons scattered by water at 25 and 75°C have been reported previously. From the results the Van Hove scattering function, S(Q, ?), was formed for wave vector transfers in the range 0.4 ? Q ? 2.0 Å-1 at 75°C and 0.4 ? Q ? 2. 6 Å-1at 25°C. Since, for the smaller values of Q used, the energy distributions for fixed Q show quasi-elastic peaks of widths much less than the resolution of the spectrometer, the results were analysed without constructing a scattering function which had been corrected for resolution. The previously reported S(Q, ?) have now been corrected for resolution. The correction has been carried out by assuming that S(Q, ?) can be represented by the quotient of a slowly varying function of e and a Lorentz function. It is found that in the region of the quasi-elastic peak S(Q, ?) can be represented by the Lorentzian form AW/?2 + W2) where A is slightly Q-dependent and W deviates only slightly from the value DQ2. D is a constant having values in good agreement with the values of the diffusion constant of water measured at the appropriate temperature. The resolution-corrected S(Q, ?) have been used to construct the frequency spectra of the velocity autocorrelation function. No evidence has been found for a dip near the origin caused by a partial separation of diffusive modes of motion from other types of modes. (author)

  5. Study of the fluid dynamic and the efficiency of displacement in oil-water systems; Estudo da fluidodinamica e da eficiencia de deslocamento em sistemas agua-oleo

    Energy Technology Data Exchange (ETDEWEB)

    Fiorese, Eliana K.; Quadri, Marintho B.; Machado, Ricardo A.F.; Nogueira, Andre L.; Lopes, Toni J. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Quimica e de Alimentos; Baptista, Renan M. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    Several operations and procedures in the oil industry are related to immiscible displacement of a fluid by another one. Some examples can be listed: the natural and artificial oil elevation from wells, the pumping of high viscosity oils through pipelines using water injection and secondary oil recovery. The performance of the last one is a direct consequence of the interfacial phenomena inherent to oil/water systems. As occur in oil leakages from submarine pipelines, the phase inversion phenomenon can also be considered in this context. Therefore, it is of major importance to realize experimental analysis of the oil/water interface stability and the facts that leads to the fingering phenomenon appearance. This phenomenon is represented into the other one like one or more fingers. The mathematical model used to describe the immiscible displacement of another one is initially developed to Hele-Shaw cells. Experimental observations with a Hele-Shaw cell enable the evaluation of the proposed model and its capability to adequately describe the viscous fingering phenomenon related to physical (density, viscosity and interfacial tension) and geometric properties of the system. (author)

  6. Modelling toehold-mediated RNA strand displacement

    OpenAIRE

    Šulc, Petr; Ouldridge, Thomas E.; Romano, Flavio; Doye, Jonathan P. K.; Louis, Ard A

    2014-01-01

    We study the thermodynamics and kinetics of an RNA toehold-mediated strand displacement reaction with a recently developed coarse-grained model of RNA. Strand displacement, during which a single strand displaces a different strand previously bound to a complementary substrate strand, is an essential mechanism in active nucleic acid nanotechnology and has also been hypothesized to occur in vivo. We study the rate of displacement reactions as a function of the length of the to...

  7. Combined effects of Mass and Velocity on forward displacement and phenomenological ratings: a functional measurement approach to the Momentum metaphor

    Directory of Open Access Journals (Sweden)

    Michel-Ange Amorim

    2010-01-01

    Full Text Available Representational Momentum (RepMo refers to the phenomenon that the vanishing position of a moving target is perceived as displaced ahead in the direction of movement. Originally taken to reflect a strict internalization of physical momentum, the finding that the target implied mass did not have an effect led to its subsequent reinterpretation as a second-order isomorphism between mental representations and principles of the physical world. However, very few studies have addressed the effects of mass on RepMo, and consistent replications of the null effect are lacking. The extent of motor engagement of the observers in RepMo tasks has, on the other hand, been suggested to determine the occurrence of the phenomenon; however, no systematic investigations were made of the degree to which it might modulate the effect of target mass. In the present work, we use Information Integration Theory to study the joint effects of different motor responses, target velocity and target mass on RepMo, and also of velocity and target mass on rating responses. Outcomes point not only to an effect of mass on RepMo, as to a differential effect of response modality on kinematic (e.g., velocity and dynamic (e.g., mass variables. Comparisons of patterns of mislocalisation with phenomenological ratings suggest that simplification of physical principles, rather than strict internalization or isomorphism per se, might underlie RepMo.

  8. The Role of Drinking Water Shortages on Human Psychological Functioning

    Directory of Open Access Journals (Sweden)

    Siamak Khodarahimi

    2014-08-01

    Full Text Available This study is grounded on an ecopsychological approach towards the effect of water shortages on human psychological functioning. The purpose of this study was to: (1 to examine the prevalence of psychological problems in rural residents with and without water shortages; (2 to evaluate human attributions about the possible causes of water scarcity; (3 to explore human coping styles towards water shortage; and (4 to recognize the role of sociocultural factors on the aforesaid factors. Participants included 3850 Iranian rural residents, those with water shortages (WWS, and those without water shortages (WOWS. A demographic questionnaire and several self-rating measures were used. Resulting data indicates that the prevalence of mental health problems is significantly higher in rural residents who suffer with water shortages. Attributional styles towards water shortages consisted of four components: personal, social, natural, and organizational. Coping styles of participants (with water shortages indicated an emotional-avoidant coping style, the utilization of water consumption methods to optimize water usage, the use of water-free technologies, social adaptation to life with regards to water, and the application of high quality technologies for water saving. Demographic and sociocultural factors influence psychological functioning with regards to water scarcity. This study demonstrates that mental health problems are more prevalent in areas with water shortages. It also indicates the impact of attributional styles, coping methods and the role of demographic and sociocultural factors on psychological functioning when water shortages occur,

  9. Irradiation damage 'displacement zone'

    International Nuclear Information System (INIS)

    It is well known that a charged particle (ion, primary atom, etc...) moving in a solid slows down and can cause a cascade of displacements of the atoms in the solid. A study is made here of the extent to which the cascade is made up, or not, of independent collisions, as a function of the energy of the initial charged particle. When the distance between the collisions is small, these latter are no longer independent; the cascade, which then has to be considered as a whole, perturbs and locates, in the irradiated solid , a zone which has been named a 'displacement zone'. It is shown that the proportion of displacement zones increases with increasing atom size (high atomic number Z), with decreasing atomic distance D in the substance considered and with decreasing energy of the ion undergoing the slowing down process (although always remaining above a few hundred eV). The proportions obtained are higher than those corresponding to the calculations of J. A. Brinkman [3]. An interatomic potential required for this work has also been determined. (author)

  10. Structure–function analysis of the RNA polymerase cleft loops elucidates initial transcription, DNA unwinding and RNA displacement

    OpenAIRE

    Naji, Souad; Bertero, Michela G.; Spitalny, Patrizia; Cramer, Patrick; Thomm, Michael

    2007-01-01

    The active center clefts of RNA polymerase (RNAP) from the archaeon Pyrococcus furiosus (Pfu) and of yeast RNAP II are nearly identical, including four protruding loops, the lid, rudder, fork 1 and fork 2. Here we present a structure–function analysis of recombinant Pfu RNAP variants lacking these cleft loops, and analyze the function of each loop at different stages of the transcription cycle. All cleft loops except fork 1 were required for promoter-directed transcription and efficient elong...

  11. Structure–function analysis of the RNA polymerase cleft loops elucidates initial transcription, DNA unwinding and RNA displacement

    Science.gov (United States)

    Naji, Souad; Bertero, Michela G.; Spitalny, Patrizia; Cramer, Patrick; Thomm, Michael

    2008-01-01

    The active center clefts of RNA polymerase (RNAP) from the archaeon Pyrococcus furiosus (Pfu) and of yeast RNAP II are nearly identical, including four protruding loops, the lid, rudder, fork 1 and fork 2. Here we present a structure–function analysis of recombinant Pfu RNAP variants lacking these cleft loops, and analyze the function of each loop at different stages of the transcription cycle. All cleft loops except fork 1 were required for promoter-directed transcription and efficient elongation. Unprimed de novo transcription required fork 2, the lid was necessary for primed initial transcription. Analysis of templates containing a pre-melted bubble showed that rewinding of upstream DNA drives RNA separation from the template. During elongation, downstream DNA strand separation required template strand binding to an invariant arginine in switch 2, and apparently interaction of an invariant arginine in fork 2 with the non-template strand. PMID:18073196

  12. Clavicle hook plate fixation for displaced lateral-third clavicle fractures (Neer type II): a functional outcome study.

    LENUS (Irish Health Repository)

    Good, Daniel W

    2012-08-01

    Controversy exists with the use of the acromioclavicular hook plate for the treatment of lateral-third clavicle fractures (Neer type II). This is thought to stem from problems associated with the hook plate causing impingement symptoms, which can cause long-term limitation of movement and pain. Our aim was to evaluate the functional outcomes of patients with lateral-third clavicle fractures treated with the hook plate.

  13. Generation of plastic influence functions for J-integral and crack opening displacement of thin-walled pipes with a short circumferential through-wall crack

    International Nuclear Information System (INIS)

    Fracture mechanics parameters such as the J-integral and crack opening displacement (COD), are necessary for Leak-Before-Break (LBB) evaluation. The famous two estimation methods, the GE/EPRI and the Reference Stress Method (RSM), have their applicability limit with regard to the ratio of a pipe mean radius to thickness (Rm/t). In order to extend their applicability limit to a thin walled pipe, several finite element analyses are performed for the J-integral and COD, and then new plastic influence functions are developed for thin-walled pipes with a short circumferential through-wall crack. With the newly generated plastic influence functions, the GE/EPRI and the RSM give closer results with those obtained from detailed finite element analyses. In addition, C*-integral and COD rate are estimated by using the new plastic influence functions and they are well matched with elastic–creep finite element analysis results under the power-law creep condition. Since the LBB concept can be applied to a piping system in a Korean Sodium-cooled Fast Reactor (SFR) which is designed to have thin-walled pipes and to operate in high temperature enough to cause creep, this paper can be applied for the LBB assessment of thin-walled pipes with a short through-wall crack in the SFR

  14. Influence of water on the work function of certain metals

    OpenAIRE

    MUSUMECI, FRANCESCO; Pollack, Gerald H

    2012-01-01

    Experiments were carried out to explore the effect of light on Au, Pt and Cu surfaces immersed in water, in order to study the changes of work function arising from the interaction between the metallic surfaces and water. The results show an action of liquid water about three times larger than that of low-temperature ice. Theoretical calculations, present in literature, have predicted values much lower than those we measured. The substantial changes in work function measured here appear to ar...

  15. Local and average crystal structure and displacements of La{sup 11}B{sub 6} and EuB{sub 6} as a function of temperature

    Energy Technology Data Exchange (ETDEWEB)

    Booth, C.H.; Sarrao, J.L.; Hundley, M.F.; Cornelius, A.L.; Kwei, G.H.; Bianchi, A.; Fisk, Z.; Lawrence, J.M.

    2001-01-30

    Measurements of both the average crystal structure from Rietveld refinement of neutron powder diffraction (NPD) data and the local structure from La L{sub III}-edge x-ray-absorption fine-structure (XAFS) are presented for a La{sup 11}B{sub 6} sample as a function of temperature ({approx}10-320 K). These data are compared to XAFS results on a EuB{sub 6} sample. The single-site La and B positional distribution widths and the La-B and La-La bond length distribution widths and their temperature dependence are compared. This comparison allows an estimate of the La and B site displacements, and we find that these sublattices are only slightly correlated with each other. Moreover, while the temperature dependence of the displacement parameters of the average sites from diffraction fit an Einstein model well, the temperature dependence of the La-B bond length distribution width requires at least two vibrational frequencies, corresponding to the La and B frequencies of the individual sites. XAFS data on EuB{sub 6} indicate that the situation is the same in the Eu compound. In addition, comparisons between data taken below and above the ferromagnetic transition temperature for EuB{sub 6} place stringent limits on the lattice involvement in the associated metal-insulator transition and the ensuing large magnetoresistance effect. This lack of lattice involvement in the magnetoresistance transition is in sharp contrast to the strong lattice involvement observed in the colossal magnetoresistance lanthanum manganese perovskites.

  16. A molecular density functional theory to study solvation in water

    CERN Document Server

    Jeanmairet, Guillaume

    2014-01-01

    A classical density functional theory is applied to study solvation of solutes in water. An approx- imate form of the excess functional is proposed for water. This functional requires the knowledge of pure solvent direct correlation functions. Those functions can be computed by using molecular simulations such as molecular dynamic or Monte Carlo. It is also possible to use functions that have been determined experimentally. The functional minimization gives access to the solvation free energy and to the equilibrium solvent density. Some correction to the functional are also proposed to get the proper tetrahedral order of solvent molecules around a charged solute and to reproduce the correct long range hydrophobic behavior of big apolar solutes. To proceed the numerical minimization of the functional, the theory has been discretized on two tridimensional grids, one for the space coordinates, the other for the angular coordinates, in a functional minimization code written in modern Fortran, mdft. This program i...

  17. Temperature dependence of mean square displacement by IN13: a comparison between trehalose and sucrose water mixtures

    International Nuclear Information System (INIS)

    An analysis in terms of elastic scans of the neutron intensity in mixtures of homologues disaccharides (i.e., trehalose and sucrose)/D2O as a function of temperature has been carried out. The study provides an effective way for characterizing the dynamical behavior, furnishing a set of parameters characterizing the 'flexibility' and the 'rigidity' that justifies the better cryptobiotic effect of trehalose in respect to sucrose. Elastic scans make evident a non-Gaussian behavior of the intensity profiles which is more marked for sucrose, with a dynamical transition at T?253 K and T?250 K for trehalose/D2O and sucrose/D2O mixtures, respectively

  18. Immiscible displacement of oil by water in consolidated porous media due to capillary imbibition under ultrasonic waves.

    Science.gov (United States)

    Hamida, Tarek; Babadagli, Tayfun

    2007-09-01

    Numerous studies done in the last four decades have demonstrated that acoustic stimulation may enhance recovery in oil reservoirs. This technology is not only technically feasible, but also serves as an economical, environmentally friendly alternative to currently accepted enhanced oil recovery (EOR) method. It requires low capital expenditure, and yields almost immediate improvement without any additional EOR agents. Despite a vast body of empirical and theoretical support, this method lacks sufficient understanding to make meaningful and consistent engineering predictions. This is in part due to the complex nature of the physical processes involved, as well as due to a shortage of fundamental/experimental research. Much of what the authors believe is happening within acoustically stimulated porous media is speculative and theoretical. This paper focuses on the effects of ultrasound on the interfacial forces between immiscible fluids. Capillary (spontaneous) imbibition of an aqueous phase into oil (or air)-saturated Berea sandstone and Indiana limestone samples experiments were conducted. Solutions of water, brine (15,000 and 150,000 ppm NaCl), anionic surfactant (sodium dodecyl diphenyloxide disulfonate), nonionic surfactant (alcohol ethoxylate) and polymer (xanthan gum) were prepared as the aqueous phase. Both counter-current and co-current geometries were tested. Due to the intrinsically unforced, gentle nature of the process, and their strong dependence on wettability, interfacial tension, viscosity and density, such experiments provide valuable insight into some of the governing mechanisms behind ultrasonic stimulation. PMID:17927413

  19. Functional systems of a pressurized water reactor

    International Nuclear Information System (INIS)

    The main topics, discussed in the present paper, are: - Principle design of the reactor coolant system - reactor pressure vessel with internals - containment design - residual heat removal and emergency cooling systems - nuclear component cooling systems - emergency feed water systems - plant electric power supply system. (orig./RW)

  20. Influence of water on the work function of certain metals

    Science.gov (United States)

    MUSUMECI, FRANCESCO; POLLACK, GERALD H.

    2012-01-01

    Experiments were carried out to explore the effect of light on Au, Pt and Cu surfaces immersed in water, in order to study the changes of work function arising from the interaction between the metallic surfaces and water. The results show an action of liquid water about three times larger than that of low-temperature ice. Theoretical calculations, present in literature, have predicted values much lower than those we measured. The substantial changes in work function measured here appear to arise from the complex structure of water in the vicinity of the metal surface. PMID:22639466

  1. Improved association in a classical density functional theory for water

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, Eric J.; Schulte, Jeff B.; Roundy, David [Department of Physics, Oregon State University, Corvallis, Oregon 97331 (United States)

    2014-03-28

    We present a modification to our recently published statistical associating fluid theory-based classical density functional theory for water. We have recently developed and tested a functional for the averaged radial distribution function at contact of the hard-sphere fluid that is dramatically more accurate at interfaces than earlier approximations. We now incorporate this improved functional into the association term of our free energy functional for water, improving its description of hydrogen bonding. We examine the effect of this improvement by studying two hard solutes (a hard hydrophobic rod and a hard sphere) and a Lennard-Jones approximation of a krypton atom solute. The improved functional leads to a moderate change in the density profile and a large decrease in the number of hydrogen bonds broken in the vicinity of the hard solutes. We find an improvement of the partial radial distribution for a krypton atom in water when compared with experiment.

  2. Displacement solid-phase extraction on mercapto-functionalized magnetite microspheres for inductively coupled plasma mass spectrometric determination of trace noble metals

    International Nuclear Information System (INIS)

    A flow injection online displacement solid-phase extraction (DSPE) via magnetic immobilization of mercapto-functionalized magnetite microspheres onto the inner walls of a knotted reactor (KR) coupled with inductively coupled plasma mass spectrometry was developed for selective preconcentration and determination of trace noble metals (Ru, Rh, Pd, Pt, Ir and Au) in complex matrices. Online DSPE of 2.7 mL aqueous solution gave the enhancement factors of 32-46 for the six noble metals in comparison with direct nebulization of aqueous sample solution, and the detection limits (3 s) of 2.1 ng L-1 for Ru, 1.9 ng L-1 for Rh, 2.5 ng L-1 for Pd, 1.8 ng L-1 for Ir, 1.9 ng L-1 for Pt and 1.7 ng L-1 for Au. The sample throughput of the developed method was about 20 samples h-1, and the relative standard deviation for eleven replicate determinations of the noble metals at the 30 ng L-1 level ranged from 1.2% to 2.1%. The recoveries of Ru, Rh, Pd, Pt, Ir and Au still maintained 90% even after successive 140 cycles of DSPE. The developed method was successfully applied to selective determination of trace Ru, Rh, Pd, Pt, Ir and Au in complex matrices.

  3. Water transport through functionalized nanotubes with tunable hydrophobicity

    Energy Technology Data Exchange (ETDEWEB)

    Moskowitz, Ian; Snyder, Mark A.; Mittal, Jeetain, E-mail: jeetain@lehigh.edu [Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, Pennsylvania 18015 (United States)

    2014-11-14

    Molecular dynamics simulations are used to study the occupancy and flow of water through nanotubes comprised of hydrophobic and hydrophilic atoms, which are arranged on a honeycomb lattice to mimic functionalized carbon nanotubes (CNTs). We consider single-file motion of TIP3P water through narrow channels of (6,6) CNTs with varying fractions (f) of hydrophilic atoms. Various arrangements of hydrophilic atoms are used to create heterogeneous nanotubes with separate hydrophobic/hydrophilic domains along the tube as well as random mixtures of the two types of atoms. The water occupancy inside the nanotube channel is found to vary nonlinearly as a function of f, and a small fraction of hydrophilic atoms (f ? 0.4) are sufficient to induce spontaneous and continuous filling of the nanotube. Interestingly, the average number of water molecules inside the channel and water flux through the nanotube are less sensitive to the specific arrangement of hydrophilic atoms than to the fraction, f. Two different regimes are observed for the water flux dependence on f – an approximately linear increase in flux as a function of f for f < 0.4, and almost no change in flux for higher f values, similar to the change in water occupancy. We are able to define an effective interaction strength between nanotube atoms and water's oxygen, based on a linear combination of interaction strengths between hydrophobic and hydrophilic nanotube atoms and water, that can quantitatively capture the observed behavior.

  4. Water transport through functionalized nanotubes with tunable hydrophobicity

    International Nuclear Information System (INIS)

    Molecular dynamics simulations are used to study the occupancy and flow of water through nanotubes comprised of hydrophobic and hydrophilic atoms, which are arranged on a honeycomb lattice to mimic functionalized carbon nanotubes (CNTs). We consider single-file motion of TIP3P water through narrow channels of (6,6) CNTs with varying fractions (f) of hydrophilic atoms. Various arrangements of hydrophilic atoms are used to create heterogeneous nanotubes with separate hydrophobic/hydrophilic domains along the tube as well as random mixtures of the two types of atoms. The water occupancy inside the nanotube channel is found to vary nonlinearly as a function of f, and a small fraction of hydrophilic atoms (f ? 0.4) are sufficient to induce spontaneous and continuous filling of the nanotube. Interestingly, the average number of water molecules inside the channel and water flux through the nanotube are less sensitive to the specific arrangement of hydrophilic atoms than to the fraction, f. Two different regimes are observed for the water flux dependence on f – an approximately linear increase in flux as a function of f for f < 0.4, and almost no change in flux for higher f values, similar to the change in water occupancy. We are able to define an effective interaction strength between nanotube atoms and water's oxygen, based on a linear combination of interaction strengths between hydrophobic and hydrophilic nanotube atoms and water, that can quantitatively capture the observed behavior

  5. Modelling toehold-mediated RNA strand displacement

    CERN Document Server

    Šulc, Petr; Romano, Flavio; Doye, Jonathan P K; Louis, Ard A

    2014-01-01

    We study the thermodynamics and kinetics of an RNA toehold-mediated strand displacement reaction with a recently developed coarse-grained model of RNA. Strand displacement, during which a single strand displaces a different strand previously bound to a complementary substrate strand, is an essential mechanism in active nucleic acid nanotechnology and has also been hypothesized to occur in vivo. We study the rate of displacement reactions as a function of the length of the toehold and temperature and make two experimentally testable predictions: that the displacement is faster if the toehold is placed at the 5' end of the substrate and that the displacement slows down with increasing temperature for longer toeholds.

  6. Density-Functional Theory Exchange-Correlation Functionals for Hydrogen Bonds in Water

    OpenAIRE

    Santra, Biswajit

    2010-01-01

    Hydrogen bonds (HBs) involving water molecules are ubiquitous in nature. However an accurate description of HBs with simulation techniques, including even quantum mechanical approaches such as density-functional theory (DFT), is a major challenge. Mainly because of a good balance between computational cost and accuracy, DFT has been routinely applied to study water in various environments, for example, liquid water, ice, adsorbed, and confined water, yet how well DFT exchange-correlation xc f...

  7. A Simple Beta-Function Model for Soil-Water Repellency as a Function of Water and Organic Carbon Contents

    DEFF Research Database (Denmark)

    Karunarathna, Anurudda Kumara; Kawamoto, Ken

    2010-01-01

    Soil-water content (?) and soil organic carbon (SOC) are key factors controlling the occurrence and magnitude of soil-water repellency (WR). Although expressions have recently been proposed to describe the nonlinear variation of WR with ?, the inclusion of easily measurable parameters in predictive WR(?) models is still lacking. In this study, a simple empirical beta function was suggested to describe the effect of changing soil-water content on the change of WR given as apparent contact angle (?) measured by the molarity of ethanol droplet (MED) method. The beta function for predicting ?(?) is based on measurement of WR on air-dry soil and three additional model parameters: the water contents at which the maximum WR (highest ?) occurs and where WR ceases (? = 90 degrees), and the maximum ? value. The MED data for three data sets from literature comprising WR measurements across moisture conditions for 19 soils were used to test the model. The beta function successfully reproduced all the measured soil-water repellency characteristic, ?(?), curves. Significant correlations were found between model parameters and SOC content (1%-14%). The model was independently tested against data for further three soils and performed accurately for all three. Consequently, we suggest that the ?(?) model represents a useful strategy to predict the entire soil-water repellency characteristic curve, and thus potential risks for enhanced runoff and preferential (fingered) soil-water flow at given initial soil-water contents, from measurements of only air-dry soil-water repellency and SOC content.

  8. Effects of wettability and pore-level displacement on hydrocarbon trapping

    Science.gov (United States)

    Suicmez, V. Sander; Piri, Mohammad; Blunt, Martin J.

    2008-03-01

    We use a three-dimensional mixed-wet random network model representing Berea sandstone to extend our previous work on relative permeability hysteresis during water-alternating-gas (WAG) injection cycles [Suicmez, VS, Piri, M, Blunt, MJ, 2007, Pore-scale simulation of water alternate gas injection, Transport Porous Med 66(3), 259-86]. We compute the trapped hydrocarbon saturation for tertiary water-flooding, which is water injection into different initial gas saturations, Sgi, established by secondary gas injection after primary drainage. Tertiary water-flooding is continued until all the gas and oil is trapped. We study four different wettability conditions: water-wet, weakly water-wet, weakly oil-wet and oil-wet. We demonstrate that the amounts of oil and gas that are trapped show surprising trends with wettability that cannot be captured using previously developed empirical trapping models. We show that the amount of oil that is trapped by water in the presence of gas increases as the medium becomes more oil-wet, which is opposite from that seen for two-phase flow. It is only through a careful analysis of displacement statistics and fluid configurations that these results can be explained. This illustrates the need to have detailed models of the displacement processes that represent the three-phase displacement physics as carefully as possible. Further work is needed to explore the full range of behavior as a function of wettability and displacement path.

  9. Water use efficiency and functional traits of a semiarid shrubland

    Science.gov (United States)

    Perez-Priego, Oscar; Lopez-Ballesteros, Ana; Sánchez-Cañete, Enrique P.; Serrano-Ortiz, Penélope; Carrara, Arnaud; Palomares-Palacio, Agustí; Oyonarte, Cecilio; Domingo, Francisco; Kowalski, Andrew S.

    2013-04-01

    In semiarid climates, water is the fundamental factor determining ecosystem productivity and thereby the capacity for carbon sequestration. Increased water use efficiency (WUE), the ratio of carbon dioxide assimilation (canopy photosynthesis, Pc) to water transpired (canopy evaporation, Ec), is assumed to be an adaptive strategy for sclerophyll shrublands to improve productivity and stress resistance in water-limited environments. However, the real complexity of WUE lies in its dependence on both plant physiological traits (e.g. stomatal resistance, photosynthetic capacity, leaf chemical composition, structure) and on environmental conditions (e.g. atmospheric CO2 concentration, vapour pressure deficit, temperature, light, soil water availability). We used a transient-state closed canopy-chamber to characterise CO2 and water vapour exchanges at the whole plant scale under different environmental conditions and phenological stages. Diurnal and seasonal variations in Pc, Ec and WUE were explained by both physiological and environmental variables. All species showed symmetric patterns in both Pc and Ec when not water limited, but asymmetry during summer drought when leaf water potential was low. During drought, grasses (Festuca sp.) showed a marked decline in functioning (Pc and Ec), whereas shrubs (Genista sp., Hormathophylla sp.) maintained spring-like assimilation rates all morning until stomatal controls shut down gas exchanges. While grasses showed the highest WUE when not water limited, their near senescence during summer drought yielded the lowest WUE. Shrubs showed reduced WUE under moderate drought stress, in contradiction to the assumptions made in global ecosystem models. The importance of the appropriate time-scale for calculating WUE (daily versus hourly), together with water use strategies and ecological functions of individual species, will be further discussed.

  10. [Eosin Y-water test for sperm function examination].

    Science.gov (United States)

    Zha, Shu-wei; Lü, Nian-qing; Xu, Hao-qin

    2015-06-01

    Based on the principles of the in vitro staining technique, hypotonic swelling test, and water test, the Eosin Y-water test method was developed to simultaneously detect the integrity of the sperm head and tail and sperm membrane structure and function. As a widely used method in clinical laboratories in China, the Eosin Y-water test is methodologically characterized by three advantages. Firstly, both the sperm head and tail can be detected at the same time, which allows easy and comprehensive assessment of membrane damage in different parts of sperm. Secondly, distilled water is used instead of the usual formula solution to simplify and standardize the test by eliminating any potential effects on the water molecules through the sperm membrane due to different osmotic pressure or different sugar proportions and electrolyte solutions. Thirdly, the test takes less time and thus can be repeated before and after treatment. This article focuses on the fundamental principles and modification of the Eosin Y-water test and its application in sperm function examination and routine semen analysis for male infertility, assessment of the quality of sperm retrieved by testicular fine needle aspiration, semen cryopreservation program development, and evaluation of sperm membrane integrity after microwave radiation. PMID:26242051

  11. Etiopathogenesis of abomasal displacement in cattle

    Directory of Open Access Journals (Sweden)

    Šamanc Horea

    2003-01-01

    Full Text Available Abomasal displacement presents topographic gastropathy, where this organ has changed its position, and there is simultaneous dilatation which can vary in intensity. The incidence of this disorder in herds of high-yield dairy cows varies to a great degree (1 to 18 %. Abomasal displacement was established in herds of East-Frisian cows in 1 to 3% animals, and in Holstein cow herds in 5 to 18 % animals. The most frequent abomasal displacement is to the left (88%. There is significant seasonal variation in the incidence of abomasal displacement. About two-thirds of cases of abomasal displacement are diagnosed from October until April. The disorder appears more frequently in cows with repeated lactations. It has been established that it appears after the first calving in 27.8% cases, after the second to fifth calving in 66.7% cases, and after the sixth and seventh calving in 5.5% of the cows. The response of endocrine pancreas B-cells for insulin secretion to hyperglycaemia caused by applying an excess-glucose test is reduced in cows with left abomasal displacement, and there is constant hyperglycaemia in cows with right abomasal displacement. The excess-glucose test indicates a disrupted function of the endocrine pancreas in diseased animals. It has been determined through examinations of Aml genotypes in Holstein cow herds in connection with the appearance of abomasal displacement, that the occurrence of this disorder cannot be attributed to a genetic predisposition.

  12. Effects of Bridge Functions on Radial Distribution Functions of Liquid Water.

    Science.gov (United States)

    Tanaka, Shigenori; Nakano, Miki

    2015-06-01

    In this report the radial distribution functions (RDFs) of liquid water are calculated on the basis of the classical density functional theory combined with the reference interaction site model for molecular liquids. The bridge functions, which are neglected in the hypernetted-chain (HNC) approximation, are taken into account through the density expansion for the Helmholtz free energy functional up to the third order. A factorization approximation to the ternary direct correlation functions in terms of the site-site pair correlation functions is then employed in the expression of the bridge functions, thus leading to a closed set of integral equations for the determination of the RDFs. It is confirmed through numerical calculations that incorporation of the oxygen-oxygen bridge function substantially improves the poor descriptions by the HNC approximation at room temperature, e.g., for the second peak of the oxygen-oxygen RDF. PMID:26188390

  13. Advanced Triangulation Displacement Sensors

    Science.gov (United States)

    Poteet, Wade M.; Cauthen, Harold K.

    1996-01-01

    Advanced optoelectronic triangulation displacement sensors undergoing development. Highly miniaturized, more stable, more accurate, and relatively easy to use. Incorporate wideband electronic circuits suitable for real-time monitoring and control of displacements. Measurements expected to be accurate to within nanometers. In principle, sensors mass-produced at relatively low unit cost. Potential applications numerous. Possible industrial application in measuring runout of rotating shaft or other moving part during fabrication in "zero-defect" manufacturing system, in which measured runout automatically corrected.

  14. Bacterial diversity and ecological function in lake water bodies

    Directory of Open Access Journals (Sweden)

    Lijuan Ren

    2013-07-01

    Full Text Available The healthy development of lake ecosystems is a global issue. Bacteria are not only an integral component of food webs, but also play a key role in controlling and regulating water quality in lake ecosystems. Hence, in order to provide some suggestions for maintaining the long-term and healthy development of lake ecosystems, this review discusses and analyses concepts and assessment of bacterial diversity, the distribution of bacteria communities, mechanisms of formation, and the ecological functions of such communities in lake water bodies. In total, there are 21 freshwater bacterial phyla typically found in lake waters at present. Among them, Proteobacteria, Cyanobacteria, Bacteroidetes, Actinobacteria and Verrucomicrobia are the most important. The Beijerinck and Baas-Becking perspective and the meta- community hypothesis suggest that bacterial community diversity and species distributions in lake water bodies are caused by the combinedaction of stochastic and determinate processes. Research on the function of lake bacteria has mainly focused on processes that bacteria are involved in, for example water quality and elemental biogeochemical cycles. Despite efforts over the past 10 years, knowledge on lake bacterial community diversity and function is still very limited. Lake bacterial ecology is still a young science, which restricts people further understanding of microbial communities in lake bodies. Future research is required on: (1 integrating bacterialphenotype, genotype, phylogeny and ecological features to define the concept of bacterial “species”; (2 the dispersal of bacteria between different locations at a regional scale; (3 bacterial community diversity and functional characteristics at the micro scale; (4 ecological theories and hypotheses of bacterial community diversity in lake ecosystems to improve the theoretical framework of microbial ecology.

  15. Loading functions for assessment of water pollution from nonpoint sources

    International Nuclear Information System (INIS)

    Methods for evaluating the quantity of water pollutants generated from nonpoint sources including agriculture, silviculture, construction, mining, runoff from urban areas and rural roads, and terrestrial disposal are developed and compiled for use in water quality planning. The loading functions, plus in some instances emission values, permit calculation of nonpoint source pollutants from available data and information. Natural background was considered to be a source and loading functions were presented to estimate natural or background loads of pollutants. Loading functions/values are presented for average conditions, i.e., annual average loads expressed as metric tons/hectare/year (tons/acre/year). Procedures for estimating seasonal or 30-day maximum and minimum loads are also presented. In addition, a wide variety of required data inputs to loading functions, and delineation of sources of additional information are included in the report. The report also presents an evaluation of limitations and constraints of various methodologies which will enable the user to employ the functions realistically

  16. Theoretical Investigations of Water Clusters, Ice Clathrates and Functionalized Nanoparticles

    OpenAIRE

    Lenz, Annika

    2009-01-01

    Nanosized structures are of intermediate size between individual molecules and bulkmaterials which gives them several unique properties. At the same time their relative limitedsizes make them suitable for studies by the methods of computational chemistry. In this thesiswater clusters, ice clathrates and functionalized metal-oxide nanoparticles have been studiedby quantum-chemical calculations and statistical thermodynamics. The stabilities of water clusters composed of up to 100 molecules hav...

  17. Soil water diffusivity as a function of water content and time

    International Nuclear Information System (INIS)

    The soil-water diffusivity has been studied as a function of water content and time. From the idea of studying the horizontal movement of water in swelling soils, a simple formulation has been achieved which allows for the diffusivity, water content dependency and time dependency, to be estimated, not only of this kind of soil, but for any other soil as well. It was observed that the internal rearrangement of soil particles is a more important phenomenon than swelling, being responsible for time dependency. The method 2? is utilized, which makes it possible to simultaneously determine the water content and density, point by point, in a soil column. The diffusivity data thus obtained are compared to those obtained when time dependency is not considered. Finally, a new soil parameter, ?, is introduced and the values obtained agrees with the internal rearrangment assumption and time dependency for diffusivity (Author)

  18. Regulation of Isotopic Composition of Water - way of Improvement of Cosmonauts Drinking Water Functional Properties

    Science.gov (United States)

    Kulikova, Ekaterina; Utina, Dina; Vorozhtsova, Svetlana; Severyuhin, Yuri; Abrosimova, Anna; Sinyak, Yuri; Ivanov, Alexander

    The problem in providing drinking water to cosmonauts is solved - at this moment there is a task to improve the functional properties of the water. One of the perspectives of this trend is the use of light isotopic water. The animal studies have shown that long-term consumption of water with a depletion of deuterium and oxygen heavy isotopes accelerates the rise of mass non-irradiated mice, the phase fluctuations reducing or increasing hematological parameters were having adaptive nature. These fluctuations didn’t overcome values beyond the physiological norm of this type of animal. It is established that the therapeutic use of light isotopic water with 35 - 90 ppm in deuterium increases the survival of irradiated mice by an average of 30%, contributes to the preservation of irradiated animals body weight. Treatment of acute radiation sickness with light isotopic water stimulates hematopoietic recovery. At the same time, keeping mice drinking light isotopic water for 7 - 8 days before the irradiation (from 4 to 8.5 Gr) has no effect on the level of radio resistance. Longer keeping mice on light isotopic water, for 14 -21 days - reduction in life expectancy, animal mass, bone marrow cellularity and the level of white blood cells in irradiated animals is noted. It was established that keeping mice on light isotopic water for 14 days before exposure in experimental animals causes an increase in the mitotic index and the frequency of formation of aberrant mitosis after 24 hours of Co(60) gamma radiation in doses of 1 , 2, and 4 Gr. Thus, it is clear that the regulation of the isotopic composition of drinking water - way to improve its functional properties.

  19. Uranium enrichment by displacement chromatography

    International Nuclear Information System (INIS)

    Natural Uranium contains 0.72% of fissile isotope 235U. Need for 235U enriched uranium for light water moderated reactors and other uses are well known. Uranium enrichment is a highly complex and tedious process owing to extremely small separation factor. Several processes have been tried; however, gaseous diffusion and centrifugation techniques based on mass dependent isotope effect are being exploited for producing enriched uranium. In the recent past, Isotope fractionation based on mass independent isotope effect such as LASER technique, ion exchange displacement chromatography etc. have drawn the attention of separation scientist and efforts are being made for development and industrial deployment of these technologies. Indian Nuclear Power Programme is based on use of natural uranium (PHWRs) and slightly enriched uranium (BWRs, PWRs) with emphasis on use of vast resources of thorium. Spent fuel from PHWRs, which is depleted in 235U (0.2 to 0.3%), appears to be a promising source of slightly enriched uranium (1 to 3% 235U). Harnessing this source for 235U enrichment would augment fuel supply for PHWR and light water reactors. Ion exchange displacement chromatography is a proliferation resistant novel technique for 235U enrichment. It is based on nuclear field shift - an isotope shift in orbital electrons resulting from the isotopic difference in nuclear size and shape. Due to this effect lighter isotope (235U) exhibits a stronger tendency for a higher valence i.e. UO22+ as compared to heavier isotope (238U). Preliminary laboratory study is being carried out at HWP, Manuguru for exploring feasibility of using ion exchange displacement chromatography for enriching 235U using 4-vinyl pyridine based anion exchange resin

  20. Study of Xe poisoning effect on fuel displacement strategies in a nuclear electric plant equipped with a natural uranium - heavy water reactor

    International Nuclear Information System (INIS)

    The effect of Xenon poisoning on fuel handling strategies in a natural uranium reactor was studied. A computer code, called PRODFIS was devised to have a permanent control on the concentrations of fission products, allowing to obtain the concentration values for a fission product, at any moment. This computer code can simultaneously follow 19 fission products and supply information at different time intervals depending on the computer storage used. The problems concerning the behaviour of Xe and Sm concentrations in the reactor and their influence on its functioning were mathematically treated. The influence of Xe concentration oscillations on the functioning of a natural uranium-heavy water reactor was analysed by means of a computer code called OSCXEN that allowed us to obtain the radial and axial values for fast and thermal neutron flows at certain time intervals and iodine and Xenon concentration values on different time ranges. Dynamic programming methods were applied to the study of the control of Xe and Sm poisoning, obtaining the solutions for two aspects of this problem, namely the minimization of the Xe concentration value and Xe concentration maximum. This problem is solved by using a control system of ''bang-bang'' type. A computer code called XENPROG was devised to determine the best version for the neutron flow when the reactor is stopped in such a way as the two conditions imposed by Xe concentration minimization or minimization of Xe concentration maximum to be fulfilled. Ex.perimental measurements were performed on the V/V. R-S reactor in order to verify the results obtained with XENPROG channel. Agreement between experimental results, applying XENPROG code indications, and results obtained bY means of calculation confirms the correctness of the computer code. (author)

  1. Supersymmetric Displaced Number States

    Directory of Open Access Journals (Sweden)

    Fredy R. Zypman

    2015-06-01

    Full Text Available We introduce, generate and study a family of supersymmetric displaced number states (SDNS that can be considered generalized coherent states of the supersymmetric harmonic oscillator. The family is created from the seminal supersymmetric boson-fermion entangling annihilation operator introduced by Aragone and Zypman and later expanded by Kornbluth and Zypman. Using the momentum representation, the states are obtained analytically in compact form as displaced supersymmetric number states. We study their position-momentum uncertainties, and their bunchiness by classifying them according to their Mandel Q-parameter in phase space. We were also able to find closed form analytical representations in the space and number basis.

  2. DISPLACEMENT-DISPERSIVE LIQUID-LIQUID MICROEXTRACTION BASED ON SOLIDIFICATION FLOATING ORGANIC DROP TRACE AMOUNTS OF LEAD IN WATER SAMPLE PRIOR TO FLAME ATOMIC ABSORPTION SPECTROMETRY DETERMINATION

    Scientific Electronic Library Online (English)

    DARYOUSH, AFZALI; MARYAM, FAYAZI; ALIMOSTA, FAVI.

    2013-03-01

    Full Text Available In this study, a novel method using displacement-dispersive liquid-liquid microextraction based on solidification of floating organic drop in complicated samples prior to flame atomic absorption spectrometry determination was developed. This method involves two consecutive dispersive liquid-liquid m [...] icroextraction based on solidification. In step I, Zn(II) ions reacted with ammonium pyrrolidine dithio carbamate (APDC) to form Zn-APDC complex and was extracted with the solidified floating organic drop microextraction procedure using 1-undecanol (extraction solvent) and ethanol (dispersive solvent). In step II, after centrifugation and solidification, the separated drop was dissolved in dimethylformamide (DMF) and then dispersed into the sample solution containing lead ion and another dispersive liquid-liquid microextraction based on solidification procedure was carried out. Due to the greater stability of Pb-APDC, Pb displaces Zn from the pre-extracted Zn-APDC and preconcentration of Pb was achieved. Under the optimized conditions, the calibration curve was linear in the range of 4-700 ng mL-1 with detection limit of 0.7 ng mL-1(3a b). The relative standard deviation of ±1.6% was obtained (n=7) and the enrichment factor was found to be 35.0.

  3. Perceived displacement explains wolfpack effect

    OpenAIRE

    Šimkovic, Matúš; Träuble, Birgit

    2014-01-01

    We investigate the influence of perceived displacement of moving agent-like stimuli on the performance in dynamic interactive tasks. In order to reliably measure perceived displacement we utilize multiple tasks with different task demands. The perceived center of an agent's body is displaced in the direction in which the agent is facing and this perceived displacement is larger than the theoretical position of the center of mass would predict. Furthermore, the displacement in the explicit jud...

  4. Ab initio liquid water from PBE0 hybrid functional simulations

    Science.gov (United States)

    Li, Zhaofeng; Wu, Xifan; Car, Roberto

    2010-03-01

    For reasons of computational efficiency, so far most ab initio molecular dynamics simulations of liquid water have been based on semi-local density functional approximations, such as PBE and BLYP. These approaches yield a liquid structure that, albeit qualitatively correct, is overstructured compared to experiment, even after nuclear quantum effects have been taken into account.footnotetextJ. A. Morrone and R. Car, Phys. Rev. Lett. 101, 017801(2008) A major cause of this inaccuracy is the delocalization error associated to semi-local density functional approximations, which, as a consequence, overestimate slightly the hydrogen bond strength in the liquid. In this work we adopt the PBE0 hybrid functional approximation, which, by mixing a fraction of exact (Hartree-Fock) exchange, reduces significantly the delocalization error of semi-local functionals. Our approach is based on a numerically efficient order-N implementation of exact exchange.footnotetextX. Wu, A. Selloni, and R. Car, Phys. Rev. B 79, 085102(2009) We find that PBE0 systematically improves the agreement of the simulated liquid with experiment. Our conclusion is substantiated by the calculated radial distribution functions, H-bond statistics, and molecular dipole distribution.

  5. Water electrolyte promoted oxidation of functional thiol groups.

    Science.gov (United States)

    Lauwers, K; Breynaert, E; Rombouts, I; Delcour, J A; Kirschhock, C E A

    2016-04-15

    The formation of disulfide bonds is of the utmost importance for a wide range of food products with gluten or globular proteins as functional agents. Here, the impact of mineral electrolyte composition of aqueous solutions on thiol oxidation kinetics was studied, using glutathione (GSH) and cysteine (CYS) as model systems. Interestingly, the oxidation rate of both compounds into their corresponding disulfides was significantly higher in common tap water than in ultrapure water. The systematic study of different electrolyte components showed that especially CaCl2 improved the oxidation rate of GSH. However, this effect was not observed for CYS, which indicated a strong impact of the local chemical environment on thiol oxidation kinetics. PMID:26675862

  6. Density-functional study of photoinduced water splitting

    International Nuclear Information System (INIS)

    We investigate the dynamics of water splitting on dye-sensitized metal (Ti, Cu) oxide surfaces, induced by direct sunlight excitation. In this study, we will consider the typical photoexcitation-followed-by-injection scheme, treating electron-injection and water splitting dynamics as independent events. The simultaneous modeling of the molecular motion and the quantum nonadiabatic transitions is achieved via the computation of the low-lying electronic states along several alternative reaction paths. Electronic structure calculations are based on a B3LYP-DFT Hamiltonian. The proposed approach combines an atomistic description of the reactants and of the immediate region of the surface, while the vibrational dynamics of the substrate is modeled as an effective bath leading to dissipation effects. The use of density-functional theory to solve the many- body electronic problem allows investigating the atomic motion of the water molecules and of a representative part of the substrate, thereby providing a theoretical and computational model capable to account simultaneously for the molecular character of the dye molecule and for the bulk properties of the surface. Furthermore, the insight emerging from this fundamental modeling can be used to optimize the chemical composition of the system to attain high incident-photon-flux-to-hydrogen-yield ratios. (full text)

  7. Tunable beam displacer

    Energy Technology Data Exchange (ETDEWEB)

    Salazar-Serrano, Luis José [ICFO-Institut de Ciènces Fotòniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona),Spain (Spain); Quantum Optics Laboratory, Universidad de los Andes, AA 4976 Bogotá D.C. (Colombia); Valencia, Alejandra [Quantum Optics Laboratory, Universidad de los Andes, AA 4976 Bogotá D.C. (Colombia); Torres, Juan P. [ICFO-Institut de Ciènces Fotòniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona),Spain (Spain); Department of Signal Theory and Communications, Universitat Politècnica de Catalunya, 08034 Barcelona (Spain)

    2015-03-15

    We report the implementation of a tunable beam displacer, composed of a polarizing beam splitter (PBS) and two mirrors, that divides an initially polarized beam into two parallel beams whose separation can be continuously tuned. The two output beams are linearly polarized with either vertical or horizontal polarization and no optical path difference is introduced between them. The wavelength dependence of the device as well as the maximum separation between the beams achievable is limited mainly by the PBS characteristics.

  8. Groundwater resources monitoring and population displacement in northern Uganda

    Science.gov (United States)

    Chalikakis, K.; Hammache, Y.; Nawa, A.; Slinski, K.; Petropoulos, G.; Muteesasira, A.

    2009-04-01

    Northern Uganda has been devastated by more than 20 years of open conflict by the LRA (Lord's Resistance Army) and the Government of Uganda. This war has been marked by extreme violence against civilians, who had been gathered in protected IDP (Internally Displaced Persons) camps. At the height of the displacement in 2007, the UN office for coordination of humanitarian affairs, estimated that nearly 2.5 million people were interned into approximately 220 camps throughout Northern Uganda. With the improved security since mid-2006, the people displaced by the conflict in Northern Uganda started to move out of the overcrowded camps and return either to their villages/parishes of origin or to resettlement/transit sites. However, basic water, sanitation and hygiene infrastructure in the return areas or any new settlements sites are minimal. People returning to their villages of origin encounter a situation where in many cases there is no access to safe water. Since 1998 ACF (Action Against Hunger, part of the Action Contre la Faim International Network) activities have been concentrated in the Acholi and Lango regions of Northern Uganda. ACF's WASH (Water, sanitation and hygiene) department interventions concern sanitation infrastructure, hygiene education and promotion as well as water points implementation. To ensure safe water access, actions are focused in borehole construction and traditional spring rehabilitation, also called "protected" springs. These activities follow the guidelines as set forth by the international WASH cluster, led by UNICEF. A three year project (2008-2010) is being implemented by ACF, to monitor the available groundwater resources in Northern Uganda. The main objectives are: 1. to monitor the groundwater quality from existing water points during different hydrological seasons, 2. to identify, if any, potential risks of contamination from population concentrations and displacement, lack of basic infrastructure and land use, and finally 3. to provide a guideline for a sustainable exploration of groundwater resources within the investigated regions, relating to population movements and potential of aquifers. To achieve these objectives a) groundwater samples are collected and analyzed (microbiologically, chemically and physically) from all types of water points, boreholes and "protected" springs, during rainy, dry and intermediate seasons, b) a network of piezometers is being installed for monitoring groundwater level, and comparison with available rainfall data will define groundwater balance. During these steps results are compared with the population's displacement and density in order to quantify the consequences towards the groundwater resources. Preliminary results after microbiological analysis show the inadequacy of traditional "protected" springs in providing safe water. Feacal pollution is observed in "protected" springs even though it was not being observed before and during rehabilitation. It is mainly due to recent population concentration around the available water resources and the lack of comprehensive hydrogeological study of the functioning of the near surface aquifers. Accordingly all operations concerning spring rehabilitation are on hold. No evidence regarding microbiological contamination was found from borehole water samples. However, high concentration in ferrous iron and total iron was found in several boreholes. Concentrations in the water of weathered bedrock are expected and specific treatment is necessary.

  9. Effects of Buoyancy Forces on Immiscible Water/Oil Displacements in a Vertically Oriented Porous Medium Effets des facteurs de flottabilité sur les déplacements non-miscibles eau/huile dans un milieu poreux vertical

    Directory of Open Access Journals (Sweden)

    Thirunavu S. R.

    2006-11-01

    Full Text Available The effects of buoyancy forces on liquid-liquid displacement processes occurring in porous media are important in a variety of practical situations, in particular during the displacement of oil from partially-depleted underground reservoirs by means of aqueous solutions. Most previous studies involving the visualization of water/oil displacements in porous media have been undertaken in horizontal two-dimensional porous medium cells. The objective of the present work was to determine the effects of buoyancy forces; on the fingering pattern and oil recovery by conducting immiscible displacement experiments in two-dimensional consolidated porous medium cells aligned in the vertical plane. In order to obtain a clear understanding of the favourable and unfavourable effects of buoyancy forces, experiments were carried out in three different flow modes, namely horizontal, vertical upward, and vertical downward. As the effects of buoyancy forces are negligible for two-dimensional porous media in the horizontal flow mode, the recoveries obtained in this mode were used as a reference for comparison with those obtained in the two vertical modes. Displacements using five different density ratios were studied. The breakthrough time and percentage oil recovery were measured in each case. The effects of buoyancy forces, viscous forces, and capillary forces, as well as the injection flow rate, were also recorded. The results obtained indicate that the effects of buoyancy forces are very pronounced at low flow rates and low oil/water density ratios, and that even a slight increase in the flow rate causes the buoyancy forces to rapidly become less significant. Les facteurs de flottabilité exercent un effet important sur les déplacements liquide/liquide en milieu poreux dans toute une gamme de situations pratiques, en particulier lorsqu'on veut déplacer l'huile de roches réservoirs partiellement épuisées à l'aide de solutions aqueuses. La plupart des études effectuées jusqu'ici ont fait intervenir la visualisation des déplacements eau/huile en deux dimensions, dans des milieux poreux horizontaux. L'objectif de la présente recherche est de déterminer les effets des facteurs de flottabilité sur le phénomène de digitation et la récupération de l'huile, en effectuant des expériences de déplacements non-miscibles sur des milieux poreux consolidés, bi-dimensionnels, à cellules alignées dans un plan vertical. Pour bien comprendre les effets positifs et négatifs des facteurs de flottabilité, nous avons effectué des expériences avec trois modes d'écoulement différents : horizontal, vertical ascendant et vertical descendant. L'effet des facteurs de flottabilité étant négligeable pour les milieux poreux bi-dimensionnels en cas d'écoulement horizontal, les données de récupération obtenues dans ce cas ont servi de référence pour comparaison avec les données obtenues en cas d'écoulement vertical. L'étude des déplacements a été effectuée avec cinq solutions de densité différente. Dans chaque cas, nous avons mesuré le temps de percée et le pourcentage de récupération de pétrole. Les effets des facteurs de flottabilité, de capillarité et de viscosité ont été enregistrés, ainsi que le débit d'injection. Les résultats obtenus indiquent que les facteurs de flottabilité exercent un effet très prononcé à faible débit et pour une faible densité huile/eau, et que la moindre augmentation du débit entraîne une baisse rapide de cet effet.

  10. Nonlinear Brownian motion - mean square displacement

    Directory of Open Access Journals (Sweden)

    W.Ebeling

    2004-01-01

    Full Text Available The stochastic dynamics of self-propelled Brownian particles is studied by means of the Langevin and the Fokker-Planck approach. We model the driving by a nonlinear friction function which has a negative part at small velocities, leading to active Brownian motion of the particles. The mean square displacement is estimated analytically and compared with numerical simulations.

  11. Does oxidation affect the water functionality of myofibrillar proteins?

    Science.gov (United States)

    Bertram, Hanne Christine; Kristensen, Mette; Østdal, Henrik; Baron, Caroline P; Young, Jette F; Andersen, Henrik Jørgen

    2007-03-21

    Water-binding properties of myofibrils extracted from porcine muscle, and added hemoglobin with and without exposure to H2O2, were characterized using low-field proton NMR T2 relaxometry. The effects of pH and ionic strength in the samples were investigated as pH was adjusted to 5.4, 6.2, and 7.0 and ionic strength was adjusted to 0.29, 0.46, and 0.71 M, respectively. The formation of dityrosine as a measure of oxidative protein cross-linking revealed a significant increase in dityrosine concentrations upon H2O2 activation. The formation of dityrosine was strongly pH-dependent and increased with decreasing pH. In addition, increased levels of thiobarbituric acid reactive substances were observed upon addition of H2O2, implying that lipid oxidation was enhanced, however, with a different oxidation pattern as compared to the myofibrillar proteins. Low-field NMR relaxation measurements revealed reduced T2 relaxation times upon H2O2 activation, which corresponds to reduced water-holding capacity upon oxidation. However, a direct relationship between degree of oxidation and T2 relaxation time was not observed with various pH values and ionic strengths, and further studies are needed for a complete understanding of the effect of oxidation on myofibrillar functionality. PMID:17316016

  12. Use of water as displacing agent in ion exchange chromatographic separation of isotope of boron using weak base ion exchange resin

    International Nuclear Information System (INIS)

    Experiments were undertaken to study the feasibility of using weakly basic anion exchange resin for enrichment of isotopes of boron by ion exchange chromatography and water as eluent. The results of experiments carried out to determine total chloride capacity (TCC), strong base capacity (SBC) of the resin at different concentrations of boric acid and enrichment profiles are reported in this paper. (author)

  13. Control rod displacement

    International Nuclear Information System (INIS)

    This patent describes a nuclear reactor including a core, cylindrical control rods, a single support means supporting the control rods from their upper ends in spaced apart positions and movable for displacing the control rods in their longitudinal direction between a first end position in which the control rods are fully inserted into the core and a second end position in which the control rods are retracted from the core, and guide means contacting discrete regions of the outer surface of each control rod at least when the control rods are in the vicinity of the second end position. The control rods are supported by the support means for longitudinal movement without rotation into and out of the core relative to the guide means to thereby cause the outer surface of the control rods to experience wear as a result of sliding contact with the guide means. The support means are so arranged with respect to the core and the guide means that it is incapable of rotation relative to the guide means. The improvement comprises displacement means being operatively coupled to a respective one of the control rods for periodically rotating the control rod in a single angular direction through an angle selected to change the locations on the outer surfaces of the control rods at which the control rods are contacted by the guide means during subsequent longitudinal movement of the control rods

  14. Vertical displacement of the mid-tropospheric water vapor boundary in the tropics derived from the VISSR Atmospheric Sounder (VAS) 6.7-micron channel

    Science.gov (United States)

    Stout, J.; Steranka, J.; Petersen, R. A.

    1984-01-01

    A technique for locating areas of upward or downward motion of the upper boundary of the midtropospheric water-vapor envelope over tropical oceans on the basis of GOES Visible/IR Spin-Scan Radiometer (VISSR) Atmospheric Sounder (VAS) 6.7-micron brightness temperatures is developed and demonstrated. The technique employs an analogy to the method developed by Schoeberl and Krueger (1983) for the bottom of the ozone layer and depends on the relationship investigated by Chesters and Uccellini (1982) between 6.7-micron brightness temperature and the pressure of the water-vapor upper boundary. The results of analysis of VAS data for the North Atlantic (20-40 deg N and 35-75 deg W) on September 5-7, 1982, are presented in maps which are shown to be physically consistent and in agreement with conventional upper-air measurements. Refinement of the method to account for horizontal advection and diffusion is suggested.

  15. Understanding the Impact of Open-Framework Conglomerates on Water-Oil Displacements: Victor Interval of the Ivishak Reservoir, Prudhoe Bay Field, Alaska

    CERN Document Server

    Gershenzon, Naum I; Ritzi, Robert W; Dominic, David F

    2014-01-01

    The Victor Unit of the Ivishak Formation in the Prudhoe Bay Oilfield is characterized by high net-to-gross fluvial sandstones and conglomerates. The highest permeability is found within sets of cross-strata of open-framework conglomerate (OFC). They are preserved within unit bar deposits and assemblages of unit bar deposits within compound (braid) bar deposits. They are thief zones limiting enhanced oil recovery. We incorporate recent research that has quantified important attributes of their sedimentary architecture within preserved deposits. We use high-resolution models to demonstrate the fundamental aspects of their control on oil production rate, water breakthrough time, and spatial and temporal distribution of residual oil saturation. We found that when the pressure gradient is oriented perpendicular to the paleoflow direction, the total oil production and the water breakthrough time are larger, and remaining oil saturation is smaller, than when it is oriented parallel to paleoflow. The pressure differe...

  16. Preserving and adapting functions to limited fresh water supply

    OpenAIRE

    Van der Zee, S. E. A. T. M.

    2010-01-01

    For agriculture/horticulture and nature, adaptation to decreasing fresh water availability is crucial in the growing seasons. Rainfall becomes concentrated in fewer, but heavier showers, the inlet of good quality water from main water courses will be under pressure, while evapotranspirative demand grows. Particularly for coastal provinces, this causes an increasing influence of brackish/saline ground water that upwells or directly enters the water courses. This influences which plants can be ...

  17. Displacement Parameter Inversion for a Novel Electromagnetic Underground Displacement Sensor

    Directory of Open Access Journals (Sweden)

    Nanying Shentu

    2014-05-01

    Full Text Available Underground displacement monitoring is an effective method to explore deep into rock and soil masses for execution of subsurface displacement measurements. It is not only an important means of geological hazards prediction and forecasting, but also a forefront, hot and sophisticated subject in current geological disaster monitoring. In previous research, the authors had designed a novel electromagnetic underground horizontal displacement sensor (called the H-type sensor by combining basic electromagnetic induction principles with modern sensing techniques and established a mutual voltage measurement theoretical model called the Equation-based Equivalent Loop Approach (EELA. Based on that work, this paper presents an underground displacement inversion approach named “EELA forward modeling-approximate inversion method”. Combining the EELA forward simulation approach with the approximate optimization inversion theory, it can deduce the underground horizontal displacement through parameter inversion of the H-type sensor. Comprehensive and comparative studies have been conducted between the experimentally measured and theoretically inversed values of horizontal displacement under counterpart conditions. The results show when the measured horizontal displacements are in the 0–100 mm range, the horizontal displacement inversion discrepancy is generally tested to be less than 3 mm under varied tilt angles and initial axial distances conditions, which indicates that our proposed parameter inversion method can predict underground horizontal displacement measurements effectively and robustly for the H-type sensor and the technique is applicable for practical geo-engineering applications.

  18. Measuring vulnerability to disaster displacement

    Science.gov (United States)

    Brink, Susan A.; Khazai, Bijan; Power, Christopher; Wenzel, Friedemann

    2015-04-01

    Large scale disasters can cause devastating impacts in terms of population displacement. Between 2008 and 2013, on average 27 million people were displaced annually by disasters (Yonetani 2014). After large events such as hurricane Katrina or the Port-au-Prince earthquake, images of inadequate public shelter and concerns about large scale and often inequitable migration have been broadcast around the world. Population displacement can often be one of the most devastating and visible impacts of a natural disaster. Despite the importance of population displacement in disaster events, measures to understand the socio-economic vulnerability of a community often use broad metrics to estimate the total socio-economic risk of an event rather than focusing on the specific impacts that a community faces in a disaster. Population displacement is complex and multi-causal with the physical impact of a disaster interacting with vulnerability arising from the response, environmental issues (e.g., weather), cultural concerns (e.g., expectations of adequate shelter), and many individual factors (e.g., mobility, risk perception). In addition to the complexity of the causes, population displacement is difficult to measure because of the wide variety of different terms and definitions and its multi-dimensional nature. When we speak of severe population displacement, we may refer to a large number of displaced people, an extended length of displacement or associated difficulties such as poor shelter quality, risk of violence and crime in shelter communities, discrimination in aid, a lack of access to employment or other difficulties that can be associated with large scale population displacement. We have completed a thorough review of the literature on disaster population displacement. Research has been conducted on historic events to understand the types of negative impacts associated with population displacement and also the vulnerability of different groups to these impacts. We aggregate these ideas into a framework of disaster displacement vulnerability that distinguishes between three main aspects of disaster displacement. Disaster displacement can be considered in terms of the number of displaced people and the length of that displacement. However, the literature emphasizes that the severity of disaster displacement can not be measured completely in quantitative terms. Thus, we include a measure representing people who are trapped and unable to leave their homes due to mobility, resources or for other reasons. Finally the third main aspect considers the difficulties that are associated with displacement and reflects the difference between the experiences of those who are displaced into safe and supportive environments as compared to those whose only alternate shelter is dangerous and inadequate for their needs. Finally, we apply the framework to demonstrate a methodology to estimate vulnerability to disaster displacement. Using data from the Global Earthquake Model (GEM) Social and Economic Vulnerability sub-National Database, we generate an index to measure the vulnerability of Japanese prefectures to the dimensions of displacement included in the framework. References Yonitani, M. (2014). Global Estimates 2014: People displaced by disasters. http://www.internal-displacement.org/publications/2014/global-estimates-2014-people-displaced-by-disasters/

  19. Mathematic Model of Green Function with Two-Dimensional Free Water Surface

    OpenAIRE

    Sujing Jin; Xing Wang; Junjun Du; Shesheng Zhang; Shengping Jin

    2013-01-01

    Adopting complex number theory, a mathematic model of Green function is built for two dimension free water surface, and an analytic expression of Green function is obtained by introducing two parameters. The intrinsic properties of Green function are discussed on vertical line and horizontal line. At last, the derivation expression of Green function is obtained from the formula of Green function.

  20. OPERA Collaboration have observed phase speed of neutrino wave function, while advanced time displacement is mainly due to finite life time of pion

    OpenAIRE

    Li, Shi-Yuan

    2011-01-01

    First we call the attention that velocity defined by ratio between some intervals of space and time respectively is sometimes ambiguous, in the framework of quantum theory. Velocity in general is not possible to be well defined as some generator of certain space-time symmetry operation. Then in section 3 by analyzing the OPERA experiment we show that the OPERA Collaboration may have measured the phase speed of the neutrino wave function. Employing a very (maybe too) simple m...

  1. Strategies for displacing oil

    Science.gov (United States)

    Rao, Vikram; Gupta, Raghubir

    2015-03-01

    Oil currently holds a monopoly on transportation fuels. Until recently biofuels were seen as the means to break this stranglehold. They will still have a part to play, but the lead role has been handed to natural gas, almost solely due to the increased availability of shale gas. The spread between oil and gas prices, unprecedented in its scale and duration, will cause a secular shift away from oil as a raw material. In the transport fuel sector, natural gas will gain traction first in the displacement of diesel fuel. Substantial innovation is occurring in the methods of producing liquid fuel from shale gas at the well site, in particular in the development of small scale distributed processes. In some cases, the financing of such small-scale plants may require new business models.

  2. Feature displacement interpolation

    DEFF Research Database (Denmark)

    Nielsen, Mads; Andresen, Per RØnsholt

    1998-01-01

    Given a sparse set of feature matches, we want to compute an interpolated dense displacement map. The application may be stereo disparity computation, flow computation, or non-rigid medical registration. Also estimation of missing image data, may be phrased in this framework. Since the features often are very sparse, the interpolation model becomes crucial. We show that a maximum likelihood estimation based on the covariance properties (Kriging) show properties more expedient than methods such as Gaussian interpolation or Tikhonov regularizations, also including scale-selection. The computational complexities are identical. We apply the maximum likelihood interpolation to growth analysis of the mandibular bone. Here, the features used are the crest-lines of the object surface.

  3. Displacement Ventilation : theory and design

    OpenAIRE

    Nielsen, Peter V

    2010-01-01

    Displacement ventilation is an interesting new type of air distribution principle which should be considered in connection with design of comfort ventilation in both smal1 and large spaces. Research activities on displacement ventilation are large all over the world and new knowledge of design methods appears continuously. This book gives an easy introduction to the basis of displacement ventilation and the chapters are written in the order which is used in a design procedure. The main text i...

  4. Job displacement penalties in Japan

    OpenAIRE

    Bognanno, Michael; Delgado, Lisa

    2005-01-01

    The costs of job displacement are examined on a sample of Japanese workers successfully provided job placement services from 2000 to 2003, a period of economic stagnation and structural change in Japan. We find that displaced workers suffer a loss of approximately $1,100 for each additional year of age. Workers also incur a large penalty when they change industries after being displaced. The age-earnings loss relationship is consistent with the operation of a delayed compensation scheme in la...

  5. National response to internal displacement

    Directory of Open Access Journals (Sweden)

    Jennifer McLean

    1998-04-01

    Full Text Available In many cases the international community acts to protect and assist the world's internally displaced people in absence of responsible and effective national action. This is, at least partly, because countries experiencing crises of internal displacement are unlikely to possess national institutions capable of effectively providing their displaced citizens with the necessary support. Strengthening national capacity for response is essential in order that governments themselves can assume immediate responsibility in humanitarian emergencies without having to depend on external aid.

  6. Point Coupled Displacement Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Real-time displacement measurement techniques are needed to acquire aerodynamic and structural system characteristics in flight. This proposal describes the...

  7. MRI of displaced meniscal fragments

    International Nuclear Information System (INIS)

    A torn meniscus frequently requires surgical fixation or debridement as definitive treatment. Meniscal tears with associated fragment displacement, such as bucket handle and flap tears, can be difficult to recognize and accurately describe on MRI, and displaced fragments can be challenging to identify at surgery. A displaced meniscal fragment can be obscured by synovium or be in a location not usually evaluated at arthroscopy. We present a pictorial essay of meniscal tears with displaced fragments in patients referred to a pediatric hospital in order to increase recognition and accurate interpretation by the radiologist, who in turn can help assist the surgeon in planning appropriate therapy. (orig.)

  8. Comparação entre as medidas inferenciais de edema de membros inferiores utilizando o Leg-O-Meter e o deslocador de água / Comparison between inferential measurements of lower limb edema utilizing the Leg-O-Meter and water displacement

    Scientific Electronic Library Online (English)

    ABC, Oliveira; CPO, Lara; SS, Lins; IT, Cunha-Filho.

    Full Text Available INTRODUÇÃO: A quantificação precisa da severidade e extensão de edema periférico é necessária antes e após a intervenção fisioterapêutica para avaliar a eficiência do tratamento. O objetivo deste estudo foi comparar as medidas de volume em membros inferiores (MMII) obtidas com dois instrumentos o Le [...] g-O-Meter (LM) e o deslocador de água (DA) em um período de 2 semanas. Materiais e métodos: Trinta e uma mulheres portadoras de edema de MMII com idade entre 20 e 70 anos participaram deste estudo. O edema foi inicialmente avaliado pela perimetria (LM) dos MMII ao nível do tornozelo e pelo volume de água deslocada após imersão do membro (DA). Após 2 semanas as medidas foram repetidas sem que houvesse alteração na medicação ou na rotina diária. Resultado: O percentual de alteração de edema no membro inferior direito (MID) com o LM e com o DA foi 0,3±4,18% e 0,9±3,31% (p=0,21), respectivamente. Para o membro inferior esquerdo o percentual de alteração foi de 0,7±3,44% e 0,5±3,84% (p=0,29), com o LM e o DA, respectivamente. A magnitude da correlação entre as medidas obtidas com o LM e o DL foi alta e significativa, variando de r=0,73 a r=0,83 (p Abstract in english Background: Precise quantification of the severity and extent of edema is necessary before and after physiotherapeutic intervention, in order to evaluate the efficiency of the treatment. The objective of this study was to compare lower limb (LL) volume measurements from two methods: Leg-O-Meter (LM) [...] and water displacement (WD), over a two-week interval. Method: Thirty-one women with LL edema, aged between 20 and 70 years, participated in this study. Edema was initially evaluated by circumference measurement (LM) at the ankle level, and by means of the volume of water displaced upon immersion of the limb (WD). After 2 weeks, these measurements were repeated without there having been any change in daily routines or medication intake. Results: the percent changes in edema in the right lower limb (RLL) using LM and WD were 0.3±4.18% and 0.9±3.31% (p=0.21), respectively. For the left lower limb (LLL) the percent changes were 0.7±3.44% and 0.5±3.84% (p=0.29), utilizing LM and WD, respectively. The magnitude of the correlation between the measurements obtained via the two techniques was high and significant, ranging from r=0.73 to r=0.83 (p

  9. Canal Lock Displacement

    Directory of Open Access Journals (Sweden)

    Rick Blanton

    2010-01-01

    Full Text Available In this project we determine the time needed for a pump to raise the water level in a canal lock in order for a boat to continue upstream. Using calculus methods and elementary physics, it was determined that it would take roughly 5 minutes for a single 60 horsepower pump to raise the water level the required 10 feet. We conclude that the lock is fairly efficient but offer some suggestions to increase the time efficiency of the lock system.

  10. Canal Lock Displacement

    OpenAIRE

    Rick Blanton

    2010-01-01

    In this project we determine the time needed for a pump to raise the water level in a canal lock in order for a boat to continue upstream. Using calculus methods and elementary physics, it was determined that it would take roughly 5 minutes for a single 60 horsepower pump to raise the water level the required 10 feet. We conclude that the lock is fairly efficient but offer some suggestions to increase the time efficiency of the lock system.

  11. Inherent Properties of Two Dimension Green Function with Linear Boundary Condition of Free Water Surface

    OpenAIRE

    Xing Wang; Chao Liu; Zhenli Sun; Mingyan Wu; Shesheng Zhang

    2013-01-01

    A mathematic model of Green function is build for two dimension free water surface. The analytic expression of Green function is obtained by introducing a parameter of complex number. The intrinsic properties of Green function are discussed for the special parameter values. The real and imaginary parts of H function are shown in the paper.

  12. Density functional theory study of water interactions on Mn-doped CeO2(1 1 1) surface

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • We studied geometric and electronic effects of water interactions on 12.5% Mn-doped CeO2(1 1 1) surface through a spin-polarized DFT + U approach. • Water molecular and dissociative interactions were favored on Mn dopant compared to those on Ce sites. • Surface oxygen vacancies formation was not promoted by water adsorption. • OH species could attach on surface O-hole (left by surface oxygen remotion) causing important structural atomic relaxations, but without changing the oxidation state of Mn and Ce cations. - Abstract: Spin-polarized density functional theory (DFT + U) periodic calculations have been performed to study water adsorption and dissociation on the 12.5% Mn-doped CeO2(1 1 1) surface. Our results indicated that Mn cation is the surface active site for water adsorption and dissociation reactions. The H2O molecule preferably adsorbs on a Mn cation, causing some relaxation of the surface O-layer and, thus, facilitating the bonding of one of the HH2O with the nearest oxygen atom. After overcoming an energy barrier of 0.46 eV, the water molecule could dissociate into OH and H species. The latter configuration is about 50% more exothermic than the molecular one, suggesting the Ce0.875Mn0.125O1.9375(1 1 1) surface would be easily hydroxylated under reaction conditions. In addition, the calculations showed that water adsorption on the Mn-doped CeO2(1 1 1) surface did not favor the creation of surface oxygen vacancies as it has been reported for pure CeO2(1 1 1). On the other hand, we created a surface oxygen defect in the slab with structural oxygen vacancies and computed water interactions on the reduced surface. Although, the adsorption of OH species in the O-hole caused many surface and subsurface atomic displacements, no changes in the oxidation state of Mn and Ce cations were detected

  13. Is Fibular Fracture Displacement Consistent with Tibiotalar Displacement?

    OpenAIRE

    van den Bekerom, Michel P.J; van Dijk, C. Niek

    2009-01-01

    We believed open reduction with internal fixation is required for supination-external rotation ankle fractures located at the level of the distal tibiofibular syndesmosis (Lauge-Hanssen SER II and Weber B) with 2 mm or more fibular fracture displacement. The rationale for surgery for these ankle fractures is based on the notion of elevated intraarticular contact pressures with lateral displacement. To diagnose these injuries, we presumed that in patients with a fibular fracture with at least ...

  14. A Measuring Method for Angular Displacement Based on Correlation Algorithm

    Directory of Open Access Journals (Sweden)

    Ping Yan

    2012-10-01

    Full Text Available The existing angular displacement measurement methods rely on the manufacturing precision of the fixed-plate and moving-plate with high manufacturing cost, and it is difficult to overcome a static error and drift for the static measurement method. A kind of angular displacement measuring method based on correlation algorithm is presented with the characteristics of a low manufacturing cost, high precision, anti-noise and anti-partially damaged properties and so on. The method is that firstly full circle broadband or white noise, random data is a pre-prepared coaxially in a rotating body, then the periodic random signal is continuously formed using pickup head reads this data in the basic uniform rotation process of the rotating body. The instantaneous angular displacement of the pickup head relative to the rotating body is obtained by means of the correlation operations between the periodic random signal and the signal sequence of pre-stored data. The angular displacement among the different pickup heads is gained by subtraction for the instantaneous angular displacement of different pickup heads relative to the rotating body at the same instant. The functional relationship between the relative angular displacement of the different pickup heads and the measured angular displacement is determined by linkage equations, which is used to calculate the measured angular displacement. Furthermore, the schematics of detective devices and the principle of the signal processing are developed to implement the method.

  15. Thermal Care of Functional Dyspepsia Based on Bicarbonate-Sulphate-Calcium Water: A Sequential Clinical Trial

    OpenAIRE

    Ferruccio Bonino; Brunetto, Maurizia R; Filippo Oliveri; Nadia Rocca; Federico Dioni; Giuseppe Rocca

    2007-01-01

    Drug treatment of functional dyspepsia is often unsatisfactory. We assessed the efficacy of a bicarbonate-sulphate-calcium thermal water cycle of 12 days, in patients with functional dyspepsia. Patients with functional dyspepsia were sent by their general practitioners to 12 days of treatment with thermal water, 200–400 ml in the morning, at temperature of 33°C (91.4 F) and were evaluated on a strict intention to treat basis. Four efficacy endpoints were analyzed as follows: (i) reduction of ...

  16. Decentralised water and wastewater treatment technologies to produce functional water for irrigation

    DEFF Research Database (Denmark)

    Battilani, Adriano; Steiner, Michele; Andersen, Martin; Back, Soren Nohr; Lorenzen, J; Schweitzer, Avi; Dalsgaard, Anders; Forslund, Anita; Gola, Secondo; Klopmann, Wolfram; Plauborg, Finn; Andersen, Mathias Neumann

    2010-01-01

    The EU project SAFIR aimed to help farmers solve problems related to the use of low quality water for irrigation in a context of increasing scarcity of conventional freshwater resources. New decentralised water treatment devices (prototypes) were developed to allow a safe direct or indirect reuse of wastewater produced by small communities/industries or the use of polluted surface water. Water treatment technologies were coupled with irrigation strategies and technologies to obtain a flexible, e...

  17. Thermodynamic properties, gradients and functions for saturated steam and water

    International Nuclear Information System (INIS)

    The tables presented in this report were produced to provide steam and water properties required in dynamic simulations of steam/water systems. In addition to the usual thermodynamic and transport properties of liquid and vapour at saturation, the tables provide certain partial derivatives of one thermodynamic property with respect to another, covering the pressure range from 0.1 to 22.0 MPa. Also tabulated are surface tension, acoustic velocities and isentropic expansion exponents for dry and wet saturated steam, shown only graphically, or not at all, in conventional steam tables. (author)

  18. Woody plant willow in function of river water protection

    Directory of Open Access Journals (Sweden)

    Babincev Ljiljana M.

    2011-01-01

    Full Text Available Coastal area surrounding the river Ibar, in the area between cities of Kosovska Mitrovica and Leposavi? in the north of Kosovo and Metohija, is occupied with seven industrial waste dumps. These dumps were all part of the exploitation and flotation refinement of raw mineral materials, metallurgic refinement of concentrates, chemical industry, industrial refinement and energetic facilities of Trep?a industrial complex. The existing waste dumps, both active and inactive, are of heterogenic chemical composition. Its impact on the river water is shown by the content of heavy metals found in it. Removal of lead, cadmium and zinc would be economically unrewarding, regardless of the technology used. Wooden plant that prevails in this area is white willow. This work is focused on the removal of heavy metals (Pb, Cd and Zn from the water of the river Ibar using white willow. Roots of the willow are cultivated using the method of water cultures in an individual solution of heavy metals and river water sample. The preparation of the samples for analysis was performed by burning the herbal material and dissolving ashes in the appropriate acids. The concentrations of metals were determined by the stripping analysis. In the investigated heavy metal solutions the biomass increase is 25.6% in lead solution, 27.3% in cadmium and 30.7% in zinc solution. The increase of biomass in nutritional solution, without the heavy metals, is 32.4% and in river water sample 27.5%. The coefficient of bioaccumulation in solutions with heavy metals is 1.6% in lead solution, 1.9% in cadmium and 2.2% in zinc solution. Heavy metals accumulation is 18.74 ?g of lead, 20.09 ?g of cadmium and 22.89 ?g of zinc. The coefficient of bioaccumulation of the water samples, that contained 44.83 ?g/dm3 of lead, 29.21 ?g/dm3 of cadmium and 434.00 ?g/dm3 of zinc, during the period of 45 days, was 30.3% for lead, 53.4% for cadmium and 3.9% for zinc. The concentrations of accumulated metals from the river water are 19.01 ?g of lead, 21.85 ?g of cadmium and 23.96 ?g of zinc in grams dry matter. The obtained results indicate that the willow can contribute to the decontamination of moderately contaminated river water from Pb, Cd and Zn.

  19. Job Displacement Insurance: An Overview

    OpenAIRE

    Parsons, Donald O.

    2014-01-01

    Earnings losses from permanent job separations are a serious threat to the financial security of long-tenured workers. Job displacement insurance is presumably designed to offset these losses, but evidence suggests that consumption smoothing among the long-tenured displaced is seriously incomplete, at least in lightly regulated labor markets. Unemployment and reemployment wage insurance could fully cover these losses, but are costly to provide. Severance pay has emerged as a supplemental, if ...

  20. Charge-displacement analysis for excited states

    Energy Technology Data Exchange (ETDEWEB)

    Ronca, Enrico, E-mail: enrico@thch.unipg.it; Tarantelli, Francesco, E-mail: francesco.tarantelli@unipg.it [Istituto CNR di Scienze e Tecnologie Molecolari, via Elce di Sotto 8, I-06123 Perugia (Italy); Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia (Italy); Pastore, Mariachiara, E-mail: chiara@thch.unipg.it; Belpassi, Leonardo; De Angelis, Filippo [Istituto CNR di Scienze e Tecnologie Molecolari, via Elce di Sotto 8, I-06123 Perugia (Italy); Angeli, Celestino; Cimiraglia, Renzo [Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Ferrara, via Borsari 46, I-44100 Ferrara (Italy)

    2014-02-07

    We extend the Charge-Displacement (CD) analysis, already successfully employed to describe the nature of intermolecular interactions [L. Belpassi et al., J. Am. Chem. Soc. 132, 13046 (2010)] and various types of controversial chemical bonds [L. Belpassi et al., J. Am. Chem. Soc. 130, 1048 (2008); N. Salvi et al., Chem. Eur. J. 16, 7231 (2010)], to study the charge fluxes accompanying electron excitations, and in particular the all-important charge-transfer (CT) phenomena. We demonstrate the usefulness of the new approach through applications to exemplary excitations in a series of molecules, encompassing various typical situations from valence, to Rydberg, to CT excitations. The CD functions defined along various spatial directions provide a detailed and insightful quantitative picture of the electron displacements taking place.

  1. Bromide as a tracer for studying water movement and nitrate displacement in soils: comparison with stable isotope tracers; Bromid als Tracer zur Untersuchung der Wasserbewegung und der Nitratverlagerung in Boeden: Vergleich mit stabilisotopen Tracern

    Energy Technology Data Exchange (ETDEWEB)

    Russow, R.; Knappe, S. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Bad Lauchstaedt (Germany). Sektion Bodenforschung

    1999-02-01

    Tracers are an ideal means of studying water movement and associated nitrate displacement. Often bromide is preferred as a tracer because it is considered a representative tracer for water and because, being a conservative tracer (i.e. not involved in chemical and biological soil processes), it can be used for studying anion transport in soils. Moreover, it is less expensive and easier to measure than the stable isotopes deuterium and {sup 15}N. Its great advantage over radioactive tracers (e.g. tritium), which outweighs their extreme sensitivity and ease of measurement and which it has in common with stable isotopes, is that it does not require radiation protection measures. However, there are also constraints on the use of bromide as a tracer in soil/water/plant systems. Our own studies on different soils using D{sub 2}O, bromide and [{sup 15}N]-nitrate in lysimeters suggest that the above assumptions on bromide tracers need not always be valid under conditions as they prevail in biologically active soils. As the present paper shows, these studies permit a good assessment of the possibilities and limits to these tracers. [Deutsch] Fuer die Untersuchung der Wasserbewegung sowie der daran gekoppelten Nitrat-Verlagerung ist der Einsatz von Tracern das Mittel der Wahl. Dabei wird Bromid als Tracer haeufig bevorzugt, da es allgemein als ein repraesentativer Tracer fuer Wasser und als konservativer Tracer (nicht involviert in chemische und biologische Bodenprozesse) zur Untersuchung des Anionentransportes in Boeden angesehen wird und es gegenueber den stabilen Isotopen Deuterium und {sup 15}N billiger und einfacher zu bestimmen ist. Gegenueber den radioaktiven Tracern (z.B. Tritium), die zwar sehr empfindlich und einfach messbar sind, besteht der grosse Vorteil, dass, wie bei den stabilen Isotopen, keine Strahlenschutzmassnahmen ergriffen werden muessen. Es gibt jedoch auch einschraenkende Hinweise fuer die Verwendung von Bromid als Tracer im System Boden/Wasser-Pflanze. Eigene Untersuchungen mit D{sub 2}O, Bromid und [{sup 15}N]Nitrat in Lysimetern mit verschiedenen Boeden weisen aber darauf hin, dass die obigen Annahmen fuer Bromid-Tracer unter den Bedingungen von biologisch aktiven Boeden nur bedingt zutreffen und lassen eine gute Einschaetzung der Moeglichkeiten und Grenzen dieser Tracer zu, wie nachstehende Ausfuehrungen zeigen. (orig.)

  2. Temporomandibular joint - normal features and disc displacements: magnetic resonance imaging

    International Nuclear Information System (INIS)

    Disc displacement of the temporomandibular joint has been defined as an abnormal relationship between the articular disc and the mandibular condyle, fossa and articular eminence. Disc displacements may occur without immediate interference in the function of the joint. Magnetic resonance imaging shows high diagnostic accuracy in the determination of articular disc position and has been indicated as the diagnostic method of choice for soft tissue abnormalities of the temporomandibular joint. The aim of this study is to review the literature including the normal features and different types of disc displacement of the temporomandibular joint as well as the imaging findings, emphasizing the role of magnetic resonance imaging. (author)

  3. Functional polyelectrolyte multilayer membranes for water purification applications

    International Nuclear Information System (INIS)

    Highlights: ? LBL film on the surface and in to the pores was prepared via flow through method. ? The membranes showed high rejection of Congo Red with sufficiently high flux. ? High antifouling ability in terms of both organic and bio fouling was observed. -- Abstract: A diverse set of supported multilayer assemblies with controllable surface charge, hydrophilicity, and permeability to water and solute was fabricated by pressure driven permeation of poly(sodium 4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDDA) solution through poly(ethylene terephthalate) (PET) track-etched membranes. The polyelectrolyte multilayer fabrication was confirmed by means of FTIR, SEM, AFM, ellipsometry, zetapotential, and contact angle characterization. The prepared membranes were characterized in terms of their pure water permeability, flux recovery, and resistance to organic and biofouling properties. The antifouling behavior of the membranes was assessed in terms of protein adsorption and antibacterial behavior. Finally, the membranes were tested for rejection of selected water soluble dyes to establish their usefulness for organic contaminant removal from water. The membranes were highly selective and capable of nearly complete rejection of congo red with sufficiently high fluxes. The feasibility of regenerating the prepared membranes fouled by protein was also demonstrated and good flux recovery was obtained. In summary, the multilayer approach to surface and pore modification was shown to enable the design of membranes with the unique combination of desirable separation characteristics, regenerability of the separation layer, and antifouling behavior

  4. Water homeostasis, frailty and congnitive function in the nursing home

    Science.gov (United States)

    The goal of this study is to develop and test a practical clinical method to assess frailty in nursing homes and to investigate the relationship between cognitive status of the elderly and the balance between water compartments of their body composition. This is a cross-sectional study, conducted a...

  5. Cost Structure of the Portuguese Water Industry: a Cubic Cost Function Application

    OpenAIRE

    Martins, Rita; Fortunato, Adelino; Coelho, Fernando

    2006-01-01

    The main scope of this paper is to confirm, or otherwise, the idea usually presented in national reports and strategic programmes for the water sector that the Portuguese water market is a natural monopoly. Based on a multi-product approach (considering the m3 of potable water delivered and wastewater collected as the outputs) we use a cubic functional specification to estimate water utilities cost function, and then to look for the presence of economies of scale and of scope. The estimated r...

  6. Water Load Test in Childhood Functional Abdominal Pain: No Relation to Food Intake and Nutritional Status.

    Science.gov (United States)

    Ozaki, Roberto Koity Fujihara; Soares, Ana Cristina Fontenele; da Graça Leite Speridião, Patricia; Batista de Morais, Mauro

    2015-09-01

    This cross-sectional study evaluates the relations between the water load test in childhood functional gastrointestinal disorders with food intake and nutritional status. Patients with functional dyspepsia required a lower maximum water intake to produce fullness (n?=?11, median?=?380 mL) than patients with irritable bowel syndrome (n?=?10, median?=?695 mL) or functional abdominal pain (n?=?10, median?=?670 mL) (P?560 mL (n?=?14) in the water load test, there was no relation between the maximum drinking capacity and food intake, body mass index, or height. PMID:26317680

  7. Topology synthesis of large-displacement compliant mechanisms

    DEFF Research Database (Denmark)

    Pedersen, Claus B. Wittendorf; Buhl, Thomas; Sigmund, Ole

    2001-01-01

    This paper describes the use of topology optimization as a synthesis tool for the design of large-displacement compliant mechanisms. An objective function for the synthesis of large-displacement mechanisms is proposed together with a formulation for synthesis of path-generating compliant mechanisms. The responses of the compliant mechanisms are modelled using a total Lagrangian finite element formulation, the sensitivity analysis is performed using the adjoint method and the optimization problem...

  8. Long-time correlation effects on displacement distributions

    International Nuclear Information System (INIS)

    The distribution of displacements in a fluid of hard disks is found by molecular dynamics to be non-Gaussian in the long-time limit, as surmised from the moments of the distribution that yield divergent diffusion and Burnett coefficients. On the other hand, for the Lorentz gas of hard disks, the distribution of displacements is Gaussian in the long-time limit and the diffusion coefficient exists, though the autocorrelation functions have power law tails, which lead to divergent Burnett coefficients

  9. The Ontario Water Works Consortium: a functional model of source water management and understanding.

    Science.gov (United States)

    Moore, L F; Watson, S B

    2007-01-01

    With an historical onus on reactive water treatment in North America, most taste and odour (T&O) outbreaks and other water quality issues have been unanticipated and difficult to control. Recent severe outbreaks of these drinking water issues have prompted wider advocacy of a more proactive "source-to-tap" approach, with greater focus on multidisciplinary partnerships among utilities, scientists and management/policy-makers. However, the practical application of this management model is faced with fragmented drainage basins, waterbodies and jurisdictions, and often requires a common issue such as T&O to initiate its development. This paper presents an example of a successful cooperative approach to drinking water management, the Ontario Water Works Research Consortium (OWWRC), consisting of the six major water utilities drawing water from Western Lake Ontario, scientists from the Canadian and Ontario governments and universities, and several other agencies. Established in 1999 following severe T&O outbreaks, the OWWRC has since operated as a highly effective model, employing a science-based approach to T&O management, supporting research on source-water and treatment issues, public outreach and utility surveys. The paper describes this partnership and summarises the results of an OWWRC T&O survey as one of the significant steps towards source-water characterisation undertaken by this cooperative. PMID:17489410

  10. A facile method to fabricate functionally integrated devices for oil/water separation

    Science.gov (United States)

    An, Qi; Zhang, Yihe; Lv, Kaikai; Luan, Xinglong; Zhang, Qian; Shi, Feng

    2015-02-01

    In this paper, we present a facile method for the fabrication of a functionally integrated device, which has the multi-functions of the oil-containment boom, oil-sorption material, and water/oil-separating film, through a single immersion step in an ethanol solution of stearic acid. During the simple immersion process, the two dominant factors of superhydrophobicity, surface roughness and low-surface-energy coatings, could be accomplished simultaneously. The as-prepared functionally integrated device with superhydrophobicity/superoleophilicity displayed a lower density than that of water, such that it could float on water and act as an oil-containment boom; an efficient oil-absorbing property, which was attributed to the capillary effect caused by micrometer-sized pore structures and could be used as oil-sorption materials; a high oil/water separating efficiency which was suitable for water/oil-separating film. In this way, the functions of oil collection, absorption, and water/oil separation are integrated into a single device, and these functions could work independently, reducing the cost in terms of energy consumption and being versatile for a wide range of applications.In this paper, we present a facile method for the fabrication of a functionally integrated device, which has the multi-functions of the oil-containment boom, oil-sorption material, and water/oil-separating film, through a single immersion step in an ethanol solution of stearic acid. During the simple immersion process, the two dominant factors of superhydrophobicity, surface roughness and low-surface-energy coatings, could be accomplished simultaneously. The as-prepared functionally integrated device with superhydrophobicity/superoleophilicity displayed a lower density than that of water, such that it could float on water and act as an oil-containment boom; an efficient oil-absorbing property, which was attributed to the capillary effect caused by micrometer-sized pore structures and could be used as oil-sorption materials; a high oil/water separating efficiency which was suitable for water/oil-separating film. In this way, the functions of oil collection, absorption, and water/oil separation are integrated into a single device, and these functions could work independently, reducing the cost in terms of energy consumption and being versatile for a wide range of applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr00026b

  11. Enhancement of Hydrophobic Solvation by Hydrophilic Functional Groups: Trehalose and Kojibiose in Water

    Science.gov (United States)

    Kramer Campen, R.; Vila Verde, Ana

    2010-03-01

    The structure and dynamics of water around biomacromolecules differs significantly from that of water in bulk in ways critical for biological function. The manner in which water structure differs is a function of both chemical and topological heterogeneity. Attempts to disentangle these effects have generally focussed on solvation of large molecules at either particular locations or in an averaged sense. In either case, understanding how chemical and topological heterogeneity combine can be difficult. Here we circumvent this problem by examining, in all atom simulations, water structure around the disaccharides Trehalose and Kojibiose. Taken together water structure around these molecules provides a series of internal control experiments for disentangling topological and chemical effects and allows us to conclude that, in the case of Trehalose, topological effects can lead to slow down of water reorientation by a factor of 2 relative to a chemically equivalent system.

  12. Structural Waters Define a Functional Channel Mediating Activation of the GPCR, rhodopsin

    Energy Technology Data Exchange (ETDEWEB)

    Angel, T.; Gupta, S; Jastrzebska, B; Palczewski, K; Chance, M

    2009-01-01

    Structural water molecules may act as prosthetic groups indispensable for proper protein function. In the case of allosteric activation of G protein-coupled receptors (GPCRs), water likely imparts structural plasticity required for agonist-induced signal transmission. Inspection of structures of GPCR superfamily members reveals the presence of conserved embedded water molecules likely important to GPCR function. Coupling radiolytic hydroxyl radical labeling with rapid H2O18 solvent mixing, we observed no exchange of these structural waters with bulk solvent in either ground state or for the Meta II or opsin states. However, the radiolysis approach permitted labeling of selected side chain residues within the transmembrane helices and revealed activation-induced changes in local structural constraints likely mediated by dynamics of both water and protein. These results suggest both a possible general mechanism for water-dependent communication in family A GPCRs based on structural conservation, and a strategy for probing membrane protein structure.

  13. Catchment water quality: the inconvenient but necessary truth of fractal functioning

    OpenAIRE

    Neal, Colin

    2013-01-01

    This commentary concerns catchment water quality functioning in relation to environmental impact assessment, with a view to proposing that much more emphasis be placed on issues of within-catchment complexity and its manifestation within stream water chemistry: fractal dynamics. The commentary is based, with closure, on my long-term research. Encouragement is given for new avenues to be pursued, including dealing with the complexities of within-stream biological functioning, and their integra...

  14. Residual value and production function approaches to valuation of irrigation water in sugar

    OpenAIRE

    Sacolo, Thabo Thandokuhle

    2013-01-01

    The main objective of the study was to estimate non-market value of irrigation water as an input in sugar cane production in the Lowveld of Swaziland. This study used two independent approaches to non-market valuation, the residual value and production function approaches, to calculate the value that sugar cane farmers in the Lowveld region of Swaziland attach to irrigation water. The former estimated the average value of water, while the latter estimated the marginal value. Th...

  15. Rampant Exchange of the Structure and Function of Extramembrane Domains between Membrane and Water Soluble Proteins

    OpenAIRE

    Nam, Hyun-Jun; Han, Seong Kyu; Bowie, James U; Kim, Sanguk

    2013-01-01

    Of the membrane proteins of known structure, we found that a remarkable 67% of the water soluble domains are structurally similar to water soluble proteins of known structure. Moreover, 41% of known water soluble protein structures share a domain with an already known membrane protein structure. We also found that functional residues are frequently conserved between extramembrane domains of membrane and soluble proteins that share structural similarity. These results suggest membrane and solu...

  16. Dynamics of confined water reconstructed from inelastic x-ray scattering measurements of bulk response functions

    Science.gov (United States)

    Coridan, Robert H.; Schmidt, Nathan W.; Lai, Ghee Hwee; Abbamonte, Peter; Wong, Gerard C. L.

    2012-03-01

    Nanoconfined water and surface-structured water impacts a broad range of fields. For water confined between hydrophilic surfaces, measurements and simulations have shown conflicting results ranging from “liquidlike” to “solidlike” behavior, from bulklike water viscosity to viscosity orders of magnitude higher. Here, we investigate how a homogeneous fluid behaves under nanoconfinement using its bulk response function: The Green's function of water extracted from a library of S(q,?) inelastic x-ray scattering data is used to make femtosecond movies of nanoconfined water. Between two confining surfaces, the structure undergoes drastic changes as a function of surface separation. For surface separations of ?9 Å, although the surface-associated hydration layers are highly deformed, they are separated by a layer of bulklike water. For separations of ?6 Å, the two surface-associated hydration layers are forced to reconstruct into a single layer that modulates between localized “frozen’ and delocalized “melted” structures due to interference of density fields. These results potentially reconcile recent conflicting experiments. Importantly, we find a different delocalized wetting regime for nanoconfined water between surfaces with high spatial frequency charge densities, where water is organized into delocalized hydration layers instead of localized hydration shells, and are strongly resistant to `freezing' down to molecular distances (<6 Å).

  17. Assessing physiological responses of dune forest functional groups to changing water availability: from Tropics to Mediterranean.

    Science.gov (United States)

    Antunes, Cristina; Lo Cascio, Mauro; Correia, Otília; Vieira, Simone; Cruz Diaz Barradas, Maria; Zunzunegui, Maria; Ramos, Margarida; João Pereira, Maria; Máguas, Cristina

    2014-05-01

    Alterations in water availability are important to vegetation as can produce dramatic changes in plant communities, on physiological performance or survival of plant species. Particularly, groundwater lowering and surface water diversions will affect vulnerable coastal dune forests, ecosystems particularly sensitive to groundwater limitation. Reduction of water tables can prevent the plants from having access to one of their key water sources and inevitably affect groundwater-dependent species. The additional impact of drought due to climatic change on groundwater-dependent ecosystems has become of increasing concern since it aggravates groundwater reduction impacts with consequent uncertainties about how vegetation will respond over the short and long term. Sand dune plant communities encompass a diverse number of species that differ widely in root depth, tolerance to drought and capacity to shift between seasonal varying water sources. Plant functional groups may be affected by water distribution and availability differently. The high ecological diversity of sand dune forests, characterized by sandy soils, well or poorly drained, poor in nutrients and with different levels of salinity, can occur in different climatic regions of the globe. Such is the case of Tropical, Meso-mediterranean and Mediterranean areas, where future climate change is predicted to change water availability. Analyses of the relative natural abundances of stable isotopes of carbon (13C/12C) and oxygen (18O/16O) have been used across a wide range of scales, contributing to our understanding of plant ecology and interactions. This approach can show important temporal and spatial changes in utilization of different water sources by vegetation. Accordingly, the core idea of this work is to evaluate, along a climatic gradient, the responses and capacity of different coastal plant communities to adapt to changing water availability. This large-climatic-scale study, covering Brazil, Portugal and Spain, provide an excellent experimental network to study the water dynamics and community functioning in natural ecosystems of high ecological value. To fulfill the main objective, a stable isotope approach (leaf ?13C and xylem+water sources ?18O) was used as a tool to assess physiological performance and water strategies integrated in spatio-temporal water dynamics. Plant functional groups' water use was characterized in a water changing situation (at different seasons) in a climatic gradient. We evaluated stress sensitivity of the functional groups to seasonal changes in water availability in different communities and tried to understand their water use strategy.

  18. Conversion function between the Linke turbidity and the atmospheric water vapor and aerosol content

    OpenAIRE

    Ineichen, Pierre

    2008-01-01

    This technical note presents a conversion function between the widely used Linke turbidity coefficient TL, the atmospheric water vapor and urban aerosol content. It takes into account the altitude of the application site. The function is based on radiative transfer calculations and validated with the help of an independent clear sky model. Its precision is around 0.12 units of TL.

  19. Functional groups in North Chilean desert shrub species, based on the water sources used

    International Nuclear Information System (INIS)

    Primary productivity and vegetation structure in arid ecosystems are determined by water availability. In studies conducted in the coastal dry land of North Central Chile (29 degrees 43'S; 71degrees 14'0, 300m), the mechanisms to use different water sources by shrubs species, in two contrasting rainfall years were compared. Information on pheno logical studies, root architecture and water sources used by shrubs through the use of stable isotopes is are discussed. Six functional groups based on water uptake and water use are recognized. The functional groups were defined based on their habits (deciduous and evergreen), their root systems, (shallow, dimorphic and deep), and their ability to use different water sources (surficial and/or deep). Because of the differential impact of the goat overgrazing on different functional groups, this would result on a lower utilization of surficial waters. A management and/or restoration plan should maximize the use of all water sources available to recover the primary productivity and the system stability

  20. A multi-functional oil-water separator from a selectively pre-wetted superamphiphobic paper.

    Science.gov (United States)

    Ge, Dengteng; Yang, Lili; Wang, Chenbo; Lee, Elaine; Zhang, Yongquan; Yang, Shu

    2015-04-11

    A multi-functional oil-water separator is prepared from a paper towel spray coated with superamphiphobic (i.e., superhydrophobic and superoleophobic) nanoparticles. After the separator is pre-wetted with ethanol, followed by water, water can be removed from the light oil-water mixture and emulsions by gravity with high separation efficiency (99.9%) and separation flux. Vice versa, heavy oil can be removed by gravity on an ethanol-oil pre-wetted SA-paper. PMID:25750982

  1. Heavy water effects on the structure, functions and behavior of biological systems

    International Nuclear Information System (INIS)

    The H2O substitution for D2O either in environment or in the culture medium of the living systems generates changes in their main functions and composition. In this paper some of the heavy water effects in biological systems such as structural and functional changes were reviewed: normal cell architecture alterations, cell division and membrane functions disturbance, muscular contractility and the perturbations of biological oscillators such as circadian rhythm, heart rate, respiratory cycle, tidal and ultradian rhythm. (authors)

  2. Displacive processes and phase transformations.

    Czech Academy of Sciences Publication Activity Database

    Paidar, Václav

    2009-01-01

    Ro?. 73, ?. 9 (2009), 1182-1187. ISSN 1062-8738 R&D Projects: GA MŠk OC 149 Institutional research plan: CEZ:AV0Z10100520 Keywords : diffusionless phase transformations * displacive processes * gamma surfaces Subject RIV: BM - Solid Matter Physics ; Magnetism

  3. Molecular Density Functional Theory for water with liquid-gas coexistence and correct pressure

    CERN Document Server

    Jeanmairet, Guillaume; Sergiievskyi, Volodymyr; Borgis, Daniel

    2015-01-01

    The solvation of hydrophobic solutes in water is special because liquid and gas are almost at coexistence. In the common hypernetted chain approximation to integral equations, or equivalently in the homogenous reference fluid of molecular density functional theory, coexistence is not taken into account. Hydration structures and energies of nanometer-scale hydrophobic solutes are thus incorrect. In this article, we propose a bridge functional that corrects this thermodynamic inconsistency by introducing a metastable gas phase for the homogeneous solvent. We show how this can be done by a third order expansion of the functional around the bulk liquid density that imposes the right pressure and the correct second order derivatives. Although this theory is not limited to water, we apply it to study hydrophobic solvation in water at room temperature and pressure and compare the results to all-atom simulations. With this correction, molecular density functional theory gives, at a modest computational cost, quantita...

  4. Decentralised water and wastewater treatment technologies to produce functional water for irrigation

    DEFF Research Database (Denmark)

    Battilani, Adriano; Steiner, Michele

    2010-01-01

    The EU project SAFIR aimed to help farmers solve problems related to the use of low quality water for irrigation in a context of increasing scarcity of conventional freshwater resources. New decentralised water treatment devices (prototypes) were developed to allow a safe direct or indirect reuse of wastewater produced by small communities/industries or the use of polluted surface water. Water treatment technologies were coupled with irrigation strategies and technologies to obtain a flexible, easy to use, integrated management of the system. The challenge is to apply new strategies and technologies which allow using the lowest irrigation water quality without harming food safety or yield and fruit or derivatives quality. This study presents the results of prototype testing of a small-scale compact pressurized membrane bioreactor and of a modular field treatment system including commercial gravel filters and heavy-metal specific adsorption materials. Decentralised compact pressurised membrane biobooster (MBR), was able to remove up to 99.99% of the inlet Escherichia coli and 98.52% of total coliforms. E. coli was completely removed from irrigation water in 53% of the samples by the last MBR prototype version. In 2008, 100% of samples fulfilled WHO standards (1989) and Global Gap requirement for faecal contamination. MBR removed from inlet flow in the average 82% of arsenic, 82% of cadmium, 97% of chromium, 93% of copper and 99% of lead. Boron and manganese were not removed from permeate. The field treatment system (FTS) proved to be effective against faecal contamination when applied with its complete set up including UV treatment. The sole gravel filter and heavy metal removal device (HMR) cannot provide sufficient and steadily treatment for microbial contamination. Nevertheless, gravel filter can remove up to 60% of E. coli but the removal process was not stable nor predictable. FTS removed 76% of arsenic, 80% of cadmium and copper, 88% of chromium and lead, and up to 97% of zinc. Like the MBR, boron and manganese were not removed from the irrigation water. Gravel filter directly fed with secondary treated wastewater was found able to remove 41% of arsenic, 36% of cadmium and lead, 48% of chromium and 46% of copper. The residual heavy metals concentration after the gravel filter was further reduced by the HMR: 35% for arsenic, 22% for cadmium, 25% for chromium, 33% for copper and 53% for lead.

  5. Monitoring Changes in Moisture Load Using Elastic Displacements in the Vadose Zone

    Science.gov (United States)

    Thrash, C. J.; Murdoch, L. C.; Germanovich, L. N.; Weinberg, A.

    2014-12-01

    Monitoring changes in mass over scales of several meters to hundreds of meters or more has many applications to characterization of the Critical Zone, including assessing changes in soil moisture, erosion or deposition of sediment, and melting or accumulation of snow or ice. A technique has been developed to monitor average changes in mass on those scales using continuous high-resolution measurements of displacement made with a vertical extensometer (called a DELTA extensometer). An increase of mass above the extensometer causes the soil to contract, which causes the extensometer to function similar to a weighing lysimeter. DELTA extensometers have been deployed at field sites near Clemson, South Carolina, and in northern Texas. The extensometers in South Carolina are in saprolite derived from biotite gneiss, whereas the ones in Texas are in clayey silt underlying playas. The instruments are in the vadose zone at depths of 3m to 6m. Signals from co-located extensometers are remarkably similar, demonstrating reproducibility of the technique. The extensometers respond to loading from a person or vehicle, and this load is used to estimate the Young's modulus of soil enveloping the extensometer. Displacement during small to moderate rainfalls is typically linear with the accumulated rain (~0.2 micron/mm of rain, for example). The displacement levels out during large rainfalls, potentially due to the onset of overland flow that would limit the water load during precipitation. This suggests that the onset of overland flow could be evaluated using this technique. Seasonal temperature fluctuations at the soil surface can penetrate to the depths of the extensometers causing displacement from thermal expansion and contraction. Thermal effects account for approximately 100 ?m of displacement over an annual cycle at one instrument. It appears that much of the thermal signal can be removed by data analysis. Pore pressure changes in the vicinity of the extensometer can also affect displacement and we are currently measuring pressures in an effort to identify this component of the signal. At one of the Texas sites, a series of step-like compressions totally 100 microns accompanied several rainfalls as water accumulated and filled the playa.

  6. Olive response to water availability: yield response functions, soil water content indicators and evaluation of adaptability to climate change

    Science.gov (United States)

    Riccardi, Maria; Alfieri, Silvia Maria; Basile, Angelo; Bonfante, Antonello; Menenti, Massimo; Monaco, Eugenia; De Lorenzi, Francesca

    2013-04-01

    Climate evolution, with the foreseen increase of temperature and frequency of drought events during the summer, could cause significant changes in the availability of water resources specially in the Mediterranean region. European countries need to encourage sustainable agriculture practices, reducing inputs, especially of water, and minimizing any negative impact on crop quantity and quality. Olive is an important crop in the Mediterranean region that has traditionally been cultivated with no irrigation and is known to attain acceptable production under dry farming. Therefore this crop will not compete for foreseen reduced water resources. However, a good quantitative knowledge must be available about effects of reduced precipitation and water availability on yield. Yield response functions, coupled with indicators of soil water availability, provide a quantitative description of the cultivar- specific behavior in relation to hydrological conditions. Yield response functions of 11 olive cultivars, typical of Mediterranean environment, were determined using experimental data (unpublished or reported in scientific literature). The yield was expressed as relative yield (Yr); the soil water availability was described by means of different indicators: relative soil water deficit (RSWD), relative evapotranspiration (RED) and transpiration deficit (RTD). Crops can respond nonlinearly to changes in their growing conditions and exhibit threshold responses, so for the yield functions of each olive cultivar both linear regression and threshold-slope models were considered to evaluate the best fit. The level of relative yield attained in rain-fed conditions was identified and defined as the acceptable yield level (Yrrainfed). The value of the indicator (RSWD, RED and RTD) corresponding to Yrrainfed was determined for each cultivar and indicated as the critical value of water availability. The error in the determination of the critical value was estimated. By means of a simulation model of the water flow in the soil-plant-atmosphere system, the indicators of soil water availability were calculated for different soil units in an area of Southern Italy, traditionally cultivated with olive. Simulations were performed for two climate scenarios: reference (1961-90) and future climate (2021-50). The potentiality of the indicators RSWD, RED and RTD to describe soil water availability was evaluated using simulated and experimental data. The analysis showed that RED values were correlated to RTD. The analysis demonstrated that RTD was more effective than RED in representing crop water availability RSWD is very well correlated to RTD and the degree of correlation depends of the period of deficit considered. The probability of adaptation of each cultivar was calculated for both climatic periods by comparing the critical values (and their error distribution) with soil availability indicators. Keywords: Olea europaea, soil water deficit, water availability critical value. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008)

  7. Metagenomic analysis reveals significant changes of microbial compositions and protective functions during drinking water treatment

    Science.gov (United States)

    Chao, Yuanqing; Ma, Liping; Yang, Ying; Ju, Feng; Zhang, Xu-Xiang; Wu, Wei-Min; Zhang, Tong

    2013-12-01

    The metagenomic approach was applied to characterize variations of microbial structure and functions in raw (RW) and treated water (TW) in a drinking water treatment plant (DWTP) at Pearl River Delta, China. Microbial structure was significantly influenced by the treatment processes, shifting from Gammaproteobacteria and Betaproteobacteria in RW to Alphaproteobacteria in TW. Further functional analysis indicated the basic metabolic functions of microorganisms in TW did not vary considerably. However, protective functions, i.e. glutathione synthesis genes in `oxidative stress' and `detoxification' subsystems, significantly increased, revealing the surviving bacteria may have higher chlorine resistance. Similar results were also found in glutathione metabolism pathway, which identified the major reaction for glutathione synthesis and supported more genes for glutathione metabolism existed in TW. This metagenomic study largely enhanced our knowledge about the influences of treatment processes, especially chlorination, on bacterial community structure and protective functions (e.g. glutathione metabolism) in ecosystems of DWTPs.

  8. Functional Abilities as a Predictor of Specific Motor Skills of Young Water Polo Players

    Science.gov (United States)

    Aleksandrovi?, Marko; Radovanovi?, Dragan; Oki?i?, Tomislav; Madi?, Dejan; Georgiev, Georgi

    2011-01-01

    The purpose of this study was to assess the influence of functional abilities on specificmotor skills. A total number of 92 male water polo players (age 12±0.5 years, body height 156.96±22.3 cm, body weight 51.02±33.18 kg) with at least two years’ experience, were enrolled in the study. The investigation protocol consisted of standardized anthropometric measurements, estimation of maximum oxygen uptake, determination of the lung function values, specific swim tests and swim tests with a ball. The factor analysis was used for the estimation of the structure of specific motor skills. The influence of functional abilities on specific motor skills was estimated by regression analysis. Out of 15 correlations in total between the variables of space of functional abilities of water polo players, 6 were significant at the level of 95% (between the variables of aerobic power and lung function) and all of the correlations (15) between the variables of specific motor skills in water polo players were significant at the 99% level. Only one principal component, the General factor of specific motor skills in water polo (GFSWP) was obtained by way of factorization of the tests of specific motor skills, so the GFSWP represents the latent space of specific motor skills as a criterion. The regression analysis showed that functional abilities (as group predictors) (p= 0.00) and forced expiratory volume in 1 second (as a separate variable) have a significant influence on GFSWP (the criterion). The results of the study pointed out the impact of functional abilities on specific motor skills of selected young water polo players. This may be important for the selection and effective coaching in the early period of training and can affect the development of more appropriate and specific training programmes for optimal physical fitness preparation in young water polo players. PMID:23486729

  9. Morphology and functions of astrocytes cultured on water-repellent fractal tripalmitin surfaces.

    Science.gov (United States)

    Hu, Wei-wei; Wang, Zhe; Zhang, Shan-shan; Jiang, Lei; Zhang, Jing; Zhang, Xiangnan; Lei, Qun-fang; Park, Hyun-Joo; Fang, Wen-jun; Chen, Zhong

    2014-08-01

    In the brain, astrocytes play an essential role with their multiple functions and sophisticated structure, as surrounded by a fractal environment which has not been available in our traditional cell culture. Water-repellent fractal tripalmitin (PPP) surfaces can imitate the fractal environment in vivo, so the morphology and biochemical characterization of astrocytes on these surfaces are examined. Water-repellent fractal PPP surface can induce astrocytes to display sophisticated morphology with smaller size of cell area, longer and finer filopodium-like processes, and higher morphological complexity. The super water-repellent fractal PPP surface with water contact angle of 150°?160° produces the maximal effects compared with other surfaces at lower water contact angles. The trends of characteristic protein expression, including that of nestin, vimentin, GFAP and glutamine synthetase, for astrocytes cultured on super water-repellent fractal PPP surfaces approximate more to in vivo pattern. The super water-repellent PPP surface also render astrocytes to perform more pronounced promotion of neurogenesis by increasing the release of nerve growth factor in a co-culture system. Altogether, our results suggest that the super water-repellent fractal PPP surface facilitates the astrocytes to mimic their in vivo performance, thus provides a closer-to-natural culture environment for experimental assessment of glial structure and functions. PMID:24894646

  10. Two-Region Model for Soil Water Repellency as a Function of Matric Potential and Water Content

    DEFF Research Database (Denmark)

    Karunarathna, Anurudda Kumara; MØldrup, Per

    2010-01-01

    Soil water repellency (WR) occurs worldwide and affects hydrologic processes such as infiltration, preferential flow, and surface erosion. The degree of WR varies with soil organic C (SOC) and water contents. In this study, we measured WR (by ethanol molarity) as a function of moisture conditions for two soil profiles (17 layers, of which 13 exhibited WR), representing different vegetation and SOC between 0.6 and 14%. Generally, WR was found at SOC ?2%. Based on measured data, a two-region water repellency (TRWR) model was developed. The model assumes two linear regions in a WR vs. pF (=log[-?], where ? is the soil water matric potential in centimeters of H2O) plot, with linear increase in WR from the moisture content where WR first occurs during drying to the maximum WR at pFWR-max, and a linear decrease from pFWR-max until ambient air-dried conditions. The van Genuchten soil water retention model was used to convert WR-? (where ? is the volumetric water content) to WR-pF. The TRWR model fitting parameters, slopes, and intercepts, were all highly correlated with SOC (R2 > 0.8). The TRWR model was tested against an independent data set for five soils with 2 to 12% SOC and predicted well the measured WR-? and WR-pF relations. For high-SOC surface soils, the TRWR model seems promising to predict WR from fully wettable to ambient air-dried conditions, i.e., within the interval where WR-induced fingered water flow probably occurs. Finally, our data imply that clay saturation by SOC (quantified by the so-called Dexter index) is useful for predicting if soils are likely to exhibit WR. Expression of soil water repellency depends on soil water content; however, only a limited amount of predictive description is available to date. In this study, based on experimental data, a simple two-region model was developed to predict the soil water repellency across the entire range of water content from air dryness to complete wetness.

  11. Testing peatland water-table depth transfer functions using high-resolution hydrological monitoring data

    Science.gov (United States)

    Swindles, Graeme T.; Holden, Joseph; Raby, Cassandra L.; Turner, T. Edward; Blundell, Antony; Charman, Dan J.; Menberu, Meseret Walle; Kløve, Bjørn

    2015-07-01

    Transfer functions are now commonly used to reconstruct past environmental variability from palaeoecological data. However, such approaches need to be critically appraised. Testate amoeba-based transfer functions are an established method for the quantitative reconstruction of past water-table variations in peatlands, and have been applied to research questions in palaeoclimatology, peatland ecohydrology and archaeology. We analysed automatically-logged peatland water-table data from dipwells located in England, Wales and Finland and a suite of three year, one year and summer water-table statistics were calculated from each location. Surface moss samples were extracted from beside each dipwell and the testate amoebae community composition was determined. Two published transfer functions were applied to the testate-amoeba data for prediction of water-table depth (England and Europe). Our results show that estimated water-table depths based on the testate amoeba community reflect directional changes, but that they are poor representations of the real mean or median water-table magnitudes for the study sites. We suggest that although testate amoeba-based reconstructions can be used to identify past shifts in peat hydrology, they cannot currently be used to establish precise hydrological baselines such as those needed to inform management and restoration of peatlands. One approach to avoid confusion with contemporary water-table determinations is to use residuals or standardised values for peatland water-table reconstructions. We contend that our test of transfer functions against independent instrumental data sets may be more powerful than relying on statistical testing alone.

  12. A fibre optic displacement sensor

    OpenAIRE

    Sohlström, Hans; Holm, Ulf

    1982-01-01

    Fibre optics is beginning to find use for sensing purposes. Fibre optic sensors have many interesting features, e.g., their immunity to interference from electromagnetic fields. The paper briefly discusses different sensor principles. A displacement sensor using multimode, step index fibres is desccribed. Measurement data showing a resolution of 0.05 nm/sqrt(Hz) in a 150 µm linear range is given. In this sensor, the light coupling between two fibre ends varies with the position of a movable ...

  13. Determination of scattering functions and their effects on remote sensing of turbidity in natural waters

    Science.gov (United States)

    Ghovanlou, A. H.; Gupta, J. N.; Henderson, R. G.

    1977-01-01

    The development of quantitative analytical procedures for relating scattered signals, measured by a remote sensor, was considered. The applications of a Monte Carlo simulation model for radiative transfer in turbid water are discussed. The model is designed to calculate the characteristics of the backscattered signal from an illuminated body of water as a function of the turbidity level, and the spectral properties of the suspended particulates. The optical properties of the environmental waters, necessary for model applications, were derived from available experimental data and/or calculated from Mie formalism. Results of applications of the model are presented.

  14. q-exponential distribution in time correlation function of water hydrogen bonds

    Scientific Electronic Library Online (English)

    M. G., Campo; G. L., Ferri; G. B., Roston.

    2009-08-01

    Full Text Available In a series of molecular dynamics simulations we analyzed structural and dynamics properties of water at different temperatures (213 K to 360 K), using the Simple Point Charge-Extended (SPC/E) water. We detected a q-exponential behavior in the history-dependent bond correlation function of hydrogen [...] bonds. We found that q increases with T -1 below approximately 300 K and is correlated to the increase of the tetrahedral structure of water and the subdiffusive motion of the molecules.

  15. The putative role of some conserved water molecules in the structure and function of human transthyretin.

    Science.gov (United States)

    Banerjee, Avik; Dasgupta, Subrata; Mukhopadhyay, Bishnu P; Sekar, Kanagaraj

    2015-11-01

    Human transthyretin (hTTR) is a multifunctional protein that is involved in several neurodegenerative diseases. Besides the transportation of thyroxin and vitamin A, it is also involved in the proteolysis of apolipoprotein A1 and A? peptide. Extensive analyses of 32 high-resolution X-ray and neutron diffraction structures of hTTR followed by molecular-dynamics simulation studies using a set of 15 selected structures affirmed the presence of 44 conserved water molecules in its dimeric structure. They are found to play several important roles in the structure and function of the protein. Eight water molecules stabilize the dimeric structure through an extensive hydrogen-bonding network. The absence of some of these water molecules in highly acidic conditions (pH ? 4.0) severely affects the interfacial hydrogen-bond network, which may destabilize the native tetrameric structure, leading to its dissociation. Three pairs of conserved water molecules contribute to maintaining the geometry of the ligand-binding cavities. Some other water molecules control the orientation and dynamics of different structural elements of hTTR. This systematic study of the location, absence, networking and interactions of the conserved water molecules may shed some light on various structural and functional aspects of the protein. The present study may also provide some rational clues about the conserved water-mediated architecture and stability of hTTR. PMID:26527142

  16. The use of a variable cost function in the regulation of the Italian water industry

    OpenAIRE

    Antonioli, Barbara; FILIPPINI, MASSIMO

    2005-01-01

    The purpose of this study is to estimate a multivariate variable cost function in order to analyze the cost structure of a sample of Italian water distribution companies. The empirical results of this study could be used by the Italian Regulation Authority of this sector for two purposes: first, to improve the actual tariff regulation process, based on a benchmarking of variable costs, and second, to define the optimal size of a service territory in this sector. A variable cost function was e...

  17. Estimating marginal value of water for irrigated olive grove with the production function method

    OpenAIRE

    Mesa-Jurado, M. A.; Berbel, J.; Orgaz Rosua, Francisco

    2010-01-01

    Economic valuation of irrigation water is done through the use of production functions for the case of the olive grove. In order to do so the integration of an agronomic model (based on the production function) and an economic model linked to the profitability of the crop (the ratio of revenue and operating costs) in the area under study is proposed. The study case encompasses the Guadalbullon River Sub-basin area, belonging to the Guadalquivir River Hydrologic Demarcation (Southern Spain). W...

  18. Lungfish Axial Muscle Function and the Vertebrate Water to Land Transition

    OpenAIRE

    Horner, Angela M.; Jayne, Bruce C.

    2014-01-01

    The role of axial form and function during the vertebrate water to land transition is poorly understood, in part because patterns of axial movement lack morphological correlates. The few studies available from elongate, semi-aquatic vertebrates suggest that moving on land may be powered simply from modifications of generalized swimming axial motor patterns and kinematics. Lungfish are an ideal group to study the role of axial function in terrestrial locomotion as they are the sister taxon to ...

  19. Displacement Compensation of Temperature Probe Data

    Science.gov (United States)

    Welch, Christopher S.; Hubert, James A.; Barber, Patrick G.

    1996-01-01

    Analysis of temperature data from a probe in a vertical Bridgman furnace growing germanium crystals revealed a displacement of the temperature profile due to conduction error. A theoretical analysis shows that the displacement compensation is independent of local temperature gradient. A displacement compensation value should become a standard characteristic of temperature probes used for temperature profile measurements.

  20. Functional water flow pathways and hydraulic regulation in the xylem network of Arabidopsis.

    Science.gov (United States)

    Park, Joonghyuk; Kim, Hae Koo; Ryu, Jeongeun; Ahn, Sungsook; Lee, Sang Joon; Hwang, Ildoo

    2015-03-01

    In vascular plants, the xylem network constitutes a complex microfluidic system. The relationship between vascular network architecture and functional hydraulic regulation during actual water flow remains unexplored. Here, we developed a method to visualize individual xylem vessels of the 3D xylem network of Arabidopsis thaliana, and to analyze the functional activities of these vessels using synchrotron X-ray computed tomography with hydrophilic gold nanoparticles as flow tracers. We show how the organization of the xylem network changes dynamically throughout the plant, and reveal how the elementary units of this transport system are organized to ensure both long-distance axial water transport and local lateral water transport. Xylem vessels form distinct clusters that operate as functional units, and the activity of these units, which determines water flow pathways, is modulated not only by varying the number and size of xylem vessels, but also by altering their interconnectivity and spatial arrangement. Based on these findings, we propose a regulatory model of water transport that ensures hydraulic efficiency and safety. PMID:25520406

  1. CHLORINATION BY-PRODUCTS IN DRINKING WATER AND MENSTRUAL CYCLE FUNCTION

    Science.gov (United States)

    Chlorination by-Products in Drinking Water and Menstrual Cycle FunctionGayle C. Windham1, Kirsten Waller2, Meredith Anderson2, Laura Fenster1, Pauline Mendola3, Shanna Swan41California Department of Health Services, Division of Environmental and Occupational Disea...

  2. Assessment of density functional approximations for the hemibonded structure of water dimer radical cation

    CERN Document Server

    Pan, Piin-Ruey; Tsai, Ming-Kang; Kuo, Jer-Lai; Chai, Jeng-Da

    2012-01-01

    Due to the severe self-interaction errors associated with some density functional approximations, conventional density functionals often fail to dissociate the hemibonded structure of water dimer radical cation (H2O)2+ into the correct fragments: H2O and H2O+. Consequently, the binding energy of the hemibonded structure (H2O)2+ is not well-defined. For a comprehensive comparison of different functionals for this system, we propose three criteria: (i) The binding energies, (ii) the relative energies between the conformers of the water dimer radical cation, and (iii) the dissociation curves predicted by different functionals. The long-range corrected (LC) double-hybrid functional, omegaB97X-2(LP) [J.-D. Chai and M. Head-Gordon, J. Chem. Phys., 2009, 131, 174105.], is shown to perform reasonably well based on these three criteria. Reasons that LC hybrid functionals generally work better than conventional density functionals for hemibonded systems are also explained in this work.

  3. Optimum Small Optical Beam Displacement Measurement

    CERN Document Server

    Hsu, M T L; Lam, P K; Bowen, W P; Hsu, Magnus T.L.; Delaubert, Vincent; Lam, Ping Koy; Bowen, Warwick

    2004-01-01

    We derive the quantum noise limit for the optical beam displacement of a TEM00 mode. Using a multimodal analysis, we show that the conventional split detection scheme for measuring beam displacement is non-optimal with 80% efficiency. We propose a new displacement measurement scheme that is optimal for small beam displacement. This scheme utilises a homodyne detection setup that has a TEM10 mode local oscillator. We show that although the quantum noise limit to displacement measurement can be surpassed using squeezed light in appropriate spatial modes for both schemes, the TEM10 homodyning scheme out-performs split detection for all values of squeezing.

  4. Displaced Children: The Psychological Implications.

    Science.gov (United States)

    Joshi, Paramjit T; Fayyad, John A

    2015-10-01

    Millions of people across the world have been displaced or live in exile and/or as refugees largely as a consequence of wars, acts of terrorism, and catastrophic natural disasters. There are serious psychological consequences as a result of these extremely difficult life circumstances. Adults often can express their needs and have them be heard, whereas children are unable to do so. The children may be provided food, shelter, and clothing and have their medical needs attended to, but their emotional and psychological needs go unrecognized and unmet, with dire and monumental long-term consequences. PMID:26346385

  5. Electromagnetic device of linear displacement

    International Nuclear Information System (INIS)

    The device moves a rod integral with a nuclear reactor control element. It has a grab for the rod operated by a mobil pole drive by a coil carried by a surrounding sealed casing, a second grab with fixed and mobile poles with facing surfaces shaped to limit the variation of magnetic force with distance between them, and a plunger driven by a coil to bear against another mobile pole moved by a coil. The invention proposes a device ensuring a displacement while the impact forces at the different level of the mechanism are reduced

  6. The thermotidal exciting function for water vapour absorption of solar radiation

    Directory of Open Access Journals (Sweden)

    M. BONAFEDE

    1976-06-01

    Full Text Available The thermotidal exciting function J is considered, for
    the absorption of solar radiation by water vapour, according to the model
    derived by Siebert. The Mugge-Moller formula for water vapour absorption
    is integrated numerically, using experimental data for the water vapour
    concentration in the troposphere and the stratosphere. It appears that
    Siebort's formula is a reasonable approximation at low tropospheric levels
    but it dramatically overestimates the water vapour thermotidal heating
    in the upper troposphere and in the stratosphere. It seems thus possible
    that, if the correct vertical profile is employed for J , the amplitudes and
    phases of the diurnal temperature oscillations and of the tidal wind speeds
    may suffer significant changes from those previously calculated and possibly explain the three hours delay of the observed phases from the computed values.

  7. Fabrication of amine-functionalized magnetite nanoparticles for water treatment processes

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Candace C. P. [University of South Australia, Ian Wark Research Institute (Australia); Gallard, Herve [Universite de Poitiers, Laboratoire de Chimie et Microbiologie de l' Eau (LCME)-UMR CNRS 6008 (France); Majewski, Peter, E-mail: peter.majewski@unisa.edu.au [Mawson Institute, University of South Australia, School of Advanced Manufacturing and Mechanical Engineering (Australia)

    2012-03-15

    Amine-functionalized magnetite nanoparticles are synthesized by a one pot water based process using N-[3-(trimethoxysilyl)propyl]diethylenetriamine (TRIS) as surfactant. The prepared functionalised nanoparticles are characterised by BET surface area measurements, X-ray diffraction, zeta potential measurement, and X-ray photoelectron spectrometry (XPS). The results clearly show the presence of TRIS on the surface of the nanoparticles. XPS analysis indicates the presence of very small amounts of maghemite on the surface of the magnetite nanoparticles. Water treatment test shows that the prepared nanoparticles are capable to remove natural organic matter (NOM) from natural water samples. The removal of NOM by the prepared particles is characterized by analysing the dissolved organic carbon (DOC) content and UV absorbance at 254 nm (UV{sub 254}) after the treatment of the water samples at various doses and treatment times.

  8. Fabrication of amine-functionalized magnetite nanoparticles for water treatment processes

    International Nuclear Information System (INIS)

    Amine-functionalized magnetite nanoparticles are synthesized by a one pot water based process using N-[3-(trimethoxysilyl)propyl]diethylenetriamine (TRIS) as surfactant. The prepared functionalised nanoparticles are characterised by BET surface area measurements, X-ray diffraction, zeta potential measurement, and X-ray photoelectron spectrometry (XPS). The results clearly show the presence of TRIS on the surface of the nanoparticles. XPS analysis indicates the presence of very small amounts of maghemite on the surface of the magnetite nanoparticles. Water treatment test shows that the prepared nanoparticles are capable to remove natural organic matter (NOM) from natural water samples. The removal of NOM by the prepared particles is characterized by analysing the dissolved organic carbon (DOC) content and UV absorbance at 254 nm (UV254) after the treatment of the water samples at various doses and treatment times.

  9. Characteristics of children with hip displacement in cerebral palsy

    Directory of Open Access Journals (Sweden)

    Wagner Philippe

    2007-10-01

    Full Text Available Abstract Background Hip dislocation in children with cerebral palsy (CP is a common and severe problem. The dislocation can be avoided, by screening and preventive treatment of children with hips at risk. The aim of this study was to analyse the characteristics of children with CP who develop hip displacement, in order to optimise a hip surveillance programme. Methods In a total population of children with CP a standardised clinical and radiological follow-up of the hips was carried out as a part of a hip prevention programme. The present study is based on 212 children followed until 9–16 years of age. Results Of the 212 children, 38 (18% developed displacement with Migration Percentage (MP >40% and further 19 (9% MP between 33 and 39%. Mean age at first registration of hip displacement was 4 years, but some hips showed MP > 40% already at two years of age. The passive range of hip motion at the time of first registration of hip displacement did not differ significantly from the findings in hips without displacement. The risk of hip displacement varied according to CP-subtype, from 0% in children with pure ataxia to 79% in children with spastic tetraplegia. The risk of displacement (MP > 40% was directly related to the level of gross motor function, classified according to the gross motor function classification system, GMFCS, from 0% in children in GMFCS level I to 64% in GMFCS level V. Conclusion Hip displacement in CP often occurs already at 2–3 years of age. Range of motion is a poor indicator of hips at risk. Thus early identification and early radiographic examination of children at risk is of great importance. The risk of hip displacement varies according to both CP-subtype and GMFCS. It is sometimes not possible to determine subtype before 4 years of age, and at present several definitions and classification systems are used. GMFCS is valid and reliable from 2 years of age, and it is internationally accepted. We recommend a hip surveillance programme for children with CP with radiographic examinations based on the child's age and GMFCS level.

  10. Diorganotin(IV) Complexes with Methionine Methyl Ester. Equilibria and Displacement by DNA Constituents

    Scientific Electronic Library Online (English)

    M.M., Shoukry; Ayser, Al-Alousi; Sameya M., Tarek.

    2014-01-01

    Full Text Available The coordination of methionine methyl ester with dimethyltin(IV) (DMT), dibutyltin(IV) (DBT) and diphenyltin(IV) (DPT) was investigated at 25 °C and 0.1 mol dm-3 ionic strength in water for dimethyltin(IV) and in 50 % dioxane-water mixture for dibutyltin(IV) and diphenyltin(IV). Methionine methyl es [...] ter forms 1:1 and 1:2 complexes with diorganotin(IV). The corresponding formation constants were calculated by using the non-linear least-squares program MINIQUAD-75. The concentration distribution of the various complex species was evaluated as a function of pH. The displacement of coordinated methionine methyl ester with some DNA constituents was calculated based on equilibrium aspects.

  11. Neurobehavioral Function in School-Age Children Exposed to Manganese in Drinking Water

    Science.gov (United States)

    Oulhote, Youssef; Mergler, Donna; Barbeau, Benoit; Bellinger, David C.; Bouffard, Thérèse; Brodeur, Marie-Ève; Saint-Amour, Dave; Legrand, Melissa; Sauvé, Sébastien

    2014-01-01

    Background: Manganese neurotoxicity is well documented in individuals occupationally exposed to airborne particulates, but few data are available on risks from drinking-water exposure. Objective: We examined associations of exposure from concentrations of manganese in water and hair with memory, attention, motor function, and parent- and teacher-reported hyperactive behaviors. Methods: We recruited 375 children and measured manganese in home tap water (MnW) and hair (MnH). We estimated manganese intake from water ingestion. Using structural equation modeling, we estimated associations between neurobehavioral functions and MnH, MnW, and manganese intake from water. We evaluated exposure–response relationships using generalized additive models. Results: After adjusting for potential confounders, a 1-SD increase in log10 MnH was associated with a significant difference of –24% (95% CI: –36, –12%) SD in memory and –25% (95% CI: –41, –9%) SD in attention. The relations between log10 MnH and poorer memory and attention were linear. A 1-SD increase in log10 MnW was associated with a significant difference of –14% (95% CI: –24, –4%) SD in memory, and this relation was nonlinear, with a steeper decline in performance at MnW > 100 ?g/L. A 1-SD increase in log10 manganese intake from water was associated with a significant difference of –11% (95% CI: –21, –0.4%) SD in motor function. The relation between log10 manganese intake and poorer motor function was linear. There was no significant association between manganese exposure and hyperactivity. Conclusion: Exposure to manganese in water was associated with poorer neurobehavioral performances in children, even at low levels commonly encountered in North America. Citation: Oulhote Y, Mergler D, Barbeau B, Bellinger DC, Bouffard T, Brodeur ME, Saint-Amour D, Legrand M, Sauvé S, Bouchard MF. 2014. Neurobehavioral function in school-age children exposed to manganese in drinking water. Environ Health Perspect 122:1343–1350;?http://dx.doi.org/10.1289/ehp.1307918 PMID:25260096

  12. Pressure effects on the reduced partition function ratio for hydrogen isotopes in water

    Science.gov (United States)

    Polyakov, V. B.; Horita, J.; Cole, D. R.

    2006-04-01

    We have developed a simple, yet accurate theoretical method for calculating the reduced isotope partition function ratio (RIPFR) for hydrogen of water at elevated pressures. This approach requires only accurate equations of state (EOS) for pure isotopic end-members (H 2O and D 2O), which are available in the literature. The effect of pressure or density on the RIPFR of water was calculated relative to that of ideal-gas water at infinitely low pressure for the temperature range from 0 to 527 °C. For gaseous and low-pressure (ca. ?15 MPa) supercritical phases of water, the RIPFR increases slightly (1-1.3‰) with pressure or density in a fashion similar to those of many other geologic materials. However, in liquid and high-pressure (>20 MPa) supercritical phases, the RIPFR of water decreases (0.5-6‰) with increasing pressure (or density) to 100 MPa. This rather unique phenomenon is ascribed to the inverse molar volume isotope effects (MVIE) of liquid and high-density supercritical waters, V (D 2O) > V (H 2O), while other substances including minerals show the normal MVIE. These theoretical predictions were experimentally confirmed by Horita et al. [Horita, J., Cole, D.R., Polyakov, V.B., Driesner, T., 2002. Experimental and theoretical study of pressure effects on hydrogen isotope fractionation in the system brucite-water at elevated temperatures. Geochim. Cosmochim. Acta66, 3769 - 3788.] for the system brucite-water. Although the P-T ranges for the EOS of normal and heavy waters are rather limited, our modeling indicates that the RIPFR of water continues to decrease with pressure above 100 MPa. The method developed here can be applied to any other geologic fluids, if accurate EOS for their isotopic end-members is available. These results have important implications for the interpretation of high-pressure isotopic partitioning in the Earth, the outer planets, and their moons.

  13. Comparison of Pattern Recognition, Artificial Neural Network and Pedotransfer Functions for Estimation of Soil Water Parameters

    Directory of Open Access Journals (Sweden)

    Amir LAKZIAN

    2010-09-01

    Full Text Available This paper presents the comparison of three different approaches to estimate soil water content at defined values of soil water potential based on selected parameters of soil solid phase. Forty different sampling locations in northeast of Iran were selected and undisturbed samples were taken to measure the water content at field capacity (FC, -33 kPa, and permanent wilting point (PWP, -1500 kPa. At each location solid particle of each sample including the percentage of sand, silt and clay were measured. Organic carbon percentage and soil texture were also determined for each soil sample at each location. Three different techniques including pattern recognition approach (k nearest neighbour, k-NN, Artificial Neural Network (ANN and pedotransfer functions (PTF were used to predict the soil water at each sampling location. Mean square deviation (MSD and its components, index of agreement (d, root mean square difference (RMSD and normalized RMSD (RMSDr were used to evaluate the performance of all the three approaches. Our results showed that k-NN and PTF performed better than ANN in prediction of water content at both FC and PWP matric potential. Various statistics criteria for simulation performance also indicated that between kNN and PTF, the former, predicted water content at PWP more accurate than PTF, however both approach showed a similar accuracy to predict water content at FC.

  14. Long-Time Mean Square Displacements in Proteins

    CERN Document Server

    Vural, Derya; Smith, Jeremy C; Glyde, Henry R

    2013-01-01

    We propose a method for obtaining the intrinsic, long time mean square displacement (MSD) of atoms and molecules in proteins from finite time molecular dynamics (MD) simulations. Typical data from simulations are limited to times of 1 to 10 ns and over this time period the calculated MSD continues to increase without a clear limiting value. The proposed method consists of fitting a model to MD simulation-derived values of the incoherent intermediate neutron scattering function, $I_{inc}(Q,t)$, for finite times. The infinite time MSD, $$, appears as a parameter in the model and is determined by fits of the model to the finite time $I_{inc}(Q,t)$. Specifically, the $$ is defined in the usual way in terms of the Debye-Waller factor as $I(Q,t = \\infty) = \\exp(- Q^2 /3)$. The method is illustrated by obtaining the intrinsic MSD $$ of hydrated lysozyme powder (h = 0.4 g water/g protein) over a wide temperature range. The intrinsic $$ obtained from data out to 1 ns and to 10 ns is found to be the same. The intrinsi...

  15. Displacement cross sections of electron irradiated graphene and carbon nanotubes

    Science.gov (United States)

    Yan, Qiang; Wang, Jing; Chen, Di; Gigax, Jonathan; Shao, Lin

    2015-05-01

    We calculate the displacement cross-sections (DCS) of low dimensional carbon systems under electron irradiation and present an analytical formula being able to evaluate displacement creations under various conditions. The calculations consider Mott scattering, charge screening effects and thermal vibrations of target atoms. DCS values of graphene and single-walled carbon nanotubes (SWNTs) as a function of electron beam energies, substrate temperatures, and tube diameters are calculated through combination with carbon threshold displacement energies obtained from molecular dynamics simulations. For SWNTs, the smaller the tube diameters the higher the DCS values. Such diameter dependence is the most pronounced for low energy electron beams. Furthermore, DCS values are most sensitive to temperatures when electron beam energy is low. However, the temperature sensitivity disappears at higher electron energy, specifically at 200 keV and beyond.

  16. Towards spatially smart abatement of human pharmaceuticals in surface waters: Defining impact of sewage treatment plants on susceptible functions.

    Science.gov (United States)

    Coppens, Lieke J C; van Gils, Jos A G; Ter Laak, Thomas L; Raterman, Bernard W; van Wezel, Annemarie P

    2015-09-15

    For human pharmaceuticals, sewage treatment plants (STPs) are a major point of entry to surface waters. The receiving waters provide vital functions. Modeling the impact of STPs on susceptible functions of the surface water system allows for a spatially smart implementation of abatement options at, or in the service area of, STPs. This study was performed on a nation-wide scale for the Netherlands. Point source emissions included were 345 Dutch STPs and nine rivers from neighboring countries. The Dutch surface waters were represented by 2511 surface water units. Modeling was performed for two extreme discharge conditions. Monitoring data of 7 locations along the rivers Rhine and Meuse fall mostly within the range of modeled concentrations. Half of the abstracted volumes of raw water for drinking water production, and a quarter of the Natura 2000 areas (European Union nature protection areas) hosted by the surface waters, are influenced by STPs at low discharge. The vast majority of the total impact of all Dutch STPs during both discharge conditions can be attributed to only 19% of the STPs with regard to the drinking water function, and to 39% of the STPs with regard to the Natura 2000 function. Attributing water treatment technologies to STPs as one of the possible measures to improve water quality and protect susceptible functions can be done in a spatially smart and cost-effective way, using consumption-based detailed hydrological and water quality modeling. PMID:26102555

  17. [The bacteriocidal effect of the electrolysed functioning water against Helicobacter pylori].

    Science.gov (United States)

    Nakao, M; Yokota, K; Oguma, K; Takai, K

    2000-02-01

    The bacteriocidal effect of electrolysed functioning water against Helicobacter pylori was examined by both the culture method (viable count on agar plate) and the bacterial ATP content analysis (biolumminescence assay). The culture method revealed the water's reduced bacteriocidal effect on organic substances such as horse serum and bovine serum albumin. The bacterial ATP content determined by the treatment with lysis solution correlated with the bacterial cell count. The ATP of bacteria treated with electrolysed functioning water, benzalkonium chloride, and chlorhexidine gluconate was still present after contact with these solutions for 30 minutes, while the bacterial growth was completely inhibited by the culture method. Therefore, it was suggested that the bacterial ATP was derived from the coccoid form which was observed morphologically due to the action of these solutions. These results demonstrate that these solutions are not effective bacteriocidally against the coccoid form. Consequently, when we utilize functioning water in the field, we should keep in mind its nonbacteriocidal effect against the coccoid form, as well as its reduced effect under the condition of the contamination by organic substances. PMID:10741002

  18. Displaced femoral neck fractures in the elderly : treatment with arthroplasties

    OpenAIRE

    Inngul, Christian

    2015-01-01

    Treatment of displaced femoral neck fractures in the elderly with arthroplasties has become standard practice during the last decade and results in good and predictable outcomes regarding hip function and health-related quality of life (HRQoL). There is, however, a lack of evidence concerning certain types of arthroplasties and different subgroups of patients. Patients with severe cognitive dysfunction have a very limited life expectancy after a hip fracture and low functional ...

  19. Structural, functional, and ACE inhibitory properties of water-soluble polysaccharides from chickpea flours.

    Science.gov (United States)

    Mokni Ghribi, Abir; Sila, Assaâd; Maklouf Gafsi, Ines; Blecker, Christophe; Danthine, Sabine; Attia, Hamadi; Bougatef, Ali; Besbes, Souhail

    2015-04-01

    The present study aimed to characterize and investigate the functional and angiotensin-I converting enzyme (ACE) inhibition activities of chickpea water-soluble polysaccharides (CPWSP). Physico-chemical characteristics were determined by nuclear magnetic resonance spectroscopy (NMR), Fourier transform-infrared spectroscopy (FT-IR) analysis, and X-ray diffractometry (XRD). Functional properties (water holding capacity: WHC, water solubility index: WSI, swelling capacity: SC, oil holding capacity: OHC, foaming, and emulsion properties) and ACE activities were also investigated using well-established procedures. The FT-IR spectra obtained for the CPWSP revealed two significant peaks, at about 3500 and 500 cm(-1), which corresponded to the carbohydrate region and were characteristic of polysaccharides. All spectra showed the presence of a broad absorption between 1500 and 670 cm(-1), which could be attributed to CH, CO, and OH bands in the polysaccharides. CPWSP had an XRD pattern that was typical for a semi-crystalline polymer with a major crystalline reflection at 19.6 °C. They also displayed important techno-functional properties (SWC, WSI, WHC, and OHC) that can be modulated according to temperature. The CPWSP were also noted to display good anti-hypertensive activities. Overall, the results indicate that CPWSP have attractive chemical, biological, and functional properties that make them potential promising candidates for application as alternative additives in various food, cosmetic, and pharmaceutical preparations. PMID:25643994

  20. Immersion freezing of water and aqueous ammonium sulphate droplets initiated by Humic Like Substances as a function of water activity

    Science.gov (United States)

    Rigg, Y. J.; Alpert, P. A.; Knopf, D. A.

    2013-02-01

    Immersion freezing of water and aqueous (NH4)2SO4 droplets containing Leonardite (LEO) and Pahokee peat (PP) serving as surrogates for Humic Like Substances (HULIS) has been investigated. Organic aerosol containing HULIS are ubiquitous in the atmosphere, however, their potential for ice cloud formation is uncertain. Immersion freezing has been studied for temperatures as low as 215 K and solution water activity, aw, from 0.85-1.0. The freezing temperatures of water and aqueous solution droplets containing LEO and PP are 5-15 K warmer than homogeneous ice nucleation temperatures. Heterogeneous freezing temperatures can be represented by a horizontal shift of the ice melting curve as a function of solution aw, ?aw, by 0.2703 and 0.2466, respectively. Corresponding heterogeneous ice nucleation rate coefficients, Jhet, are (9.6 ± 2.5)×104 and (5.4 ± 1.4)×104 cm-2 s-1 for LEO and PP containing droplets, respectively, and remain constant along freezing curves characterized by ?aw. Consequently predictions of freezing temperatures and kinetics can be made without knowledge of the solute type when relative humidity and IN surface areas are known. The acquired ice nucleation data are applied to evaluate different approaches to fit and reproduce experimentally derived frozen fractions. In addition, we apply a basic formulation of classical nucleation theory (?(T)-model) to calculate contact angles and frozen fractions. Contact angles calculated for each ice nucleus as a function of temperature, ?(T)-model, reproduce exactly experimentally derived frozen fractions without involving free fit parameters. However, assigning the IN a single contact angle for entire population (single-? model) is not suited to represent the frozen fractions. Application of ?-PDF, active sites, and deterministic model approaches to measured frozen fractions yield similar good representations. Thus, from fitting frozen fractions only, the underlying ice nucleation mechanism and nature of the ice nucleating sites cannot be inferred. In contrast to using fitted functions obtained to represent experimental conditions only, we suggest to use experimentally derived Jhet as a function of temperature and aw that can be applied to conditions outside of those probed in laboratory. This is because Jhet(T) is independent of time and IN surface areas in contrast to the fit parameters obtained by representation of experimentally derived frozen fractions.

  1. Density functional theory study on water-gas-shift reaction over molybdenum disulfide

    DEFF Research Database (Denmark)

    Shi, X. R.; Wang, Shengguang; Hu, J.; Wang, H.; Chen, Y. Y.; Qin, Z. F.; Wang, J. G.

    2009-01-01

    Density functional theory calculations have been carried out to investigate the adsorption of reaction intermediates appearing during water-gas-shift reaction at the sulfur covered MoS2 (1 0 0)surfaces, Mo-termination with 37.5% S coverage and S-termination with 50% S coverage using periodic slabs. The pathway for water-gas-shift reaction on both terminations has been carefully studied where the most favorable reaction path precedes the redox mechanism, namely the reaction takes place as follows...

  2. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    International Nuclear Information System (INIS)

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  3. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Okoli, Chuka [Royal Institute of Technology (KTH), Environmental Microbiology (Sweden); Boutonnet, Magali; Jaeras, Sven [Royal Institute of Technology (KTH), Chemical Technology (Sweden); Rajarao-Kuttuva, Gunaratna, E-mail: gkr@kth.se [Royal Institute of Technology (KTH), Environmental Microbiology (Sweden)

    2012-10-15

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  4. Density Functional Theory Meta-GGA+U Study of Water Incorporation in the Metal Organic Framework Material Cu-BTC

    OpenAIRE

    Cockayne, Eric; Nelson, Eric B

    2015-01-01

    Water absorption in the metal-organic framework (MOF) material Cu-BTC, up to a concentration of 3.5 H$_2$O per Cu ion, is studied via density functional theory at the meta-GGA+U level. The stable arrangements of water molecules show chains of hydrogen-bonded water molecules and a tendency to form closed cages at high concentration. Water clusters are stabilized primarily by a combination of water-water hydrogen bonding and Cu-water oxygen interactions. Stability is further e...

  5. The population genetics of sperm displacement

    DEFF Research Database (Denmark)

    Prout, Timothy; Bundgaard, JØrgen

    1977-01-01

    This article reports the results of some sperm displacement experiments, as well as the results of a theoretical study of selection arising from genetic differences in displacing ability. The experimental work involved the use of three genetic marker stocks in double and triple matings. The speed of displacement following the matings was determined by scoring the progeny of each female daily. There were clear differences between strains in their displacing ability. It is shown how new information concerning the displacement process results when three markers are used; however, no new light is shed by these experiments on the mechanism of displacement. The theoretical study of selection resulting from displacement uses a one-locus, two-allele model in which three diploid male genotypes confer different displacing abilities. The results indicate stable equilibria if (1) there is heterosis, and (2) there are certain nontransitive relationships in displacing ability among the different kinds of double matings. Some evolutionary consequences are discussed in which sperm displacement is regarded as a form of sexual selection.

  6. Preventing re-displacement through genuine reintegration in Burundi

    Directory of Open Access Journals (Sweden)

    Lucy Hovil

    2012-12-01

    Full Text Available Displacement is often part of a cyclical process of conflict anddisplacement. Preventing displacement, therefore, is not only aboutpreventing new displacement but about ensuring that people do notget re-displaced.

  7. What can density functional theory tell us about artificial catalytic water splitting?

    Science.gov (United States)

    Mavros, Michael G; Tsuchimochi, Takashi; Kowalczyk, Tim; McIsaac, Alexandra; Wang, Lee-Ping; Voorhis, Troy Van

    2014-07-01

    Water splitting by artificial catalysts is a critical process in the production of hydrogen gas as an alternative fuel. In this paper, we examine the essential role of theoretical calculations, with particular focus on density functional theory (DFT), in understanding the water-splitting reaction on these catalysts. First, we present an overview of DFT thermochemical calculations on water-splitting catalysts, addressing how these calculations are adapted to condensed phases and room temperature. We show how DFT-derived chemical descriptors of reactivity can be surprisingly good estimators for reactive trends in water-splitting catalysts. Using this concept, we recover trends for bulk catalysts using simple model complexes for at least the first-row transition-metal oxides. Then, using the CoPi cobalt oxide catalyst as a case study, we examine the usefulness of simulation for predicting the kinetics of water splitting. We demonstrate that the appropriate treatment of solvent effects is critical for computing accurate redox potentials with DFT, which, in turn, determine the rate-limiting steps and electrochemical overpotentials. Finally, we examine the ability of DFT to predict mechanism, using ruthenium complexes as a focal point for discussion. Our discussion is intended to provide an overview of the current strengths and weaknesses of the state-of-the-art DFT methodologies for condensed-phase molecular simulation involving transition metals and also to guide future experiments and computations toward the understanding and development of novel water-splitting catalysts. PMID:24694041

  8. Analysis of irreversible displacements of Daniel-Johnson dam

    Energy Technology Data Exchange (ETDEWEB)

    Chouinard, L.; Zhao, W. [McGill Univ., Montreal, PQ (Canada); Lariviere, R. [Hydro-Quebec, Montreal, PQ (Canada); Cote, P. [Hydro-Quebec Production, Baie-Comeau, PQ (Canada)

    2006-07-01

    Irreversible displacements in dams are associated with alkali-aggregate reaction, creep, and other damaging effects that compromise the safety of dams. An identification of the nature of irreversible displacements is needed to predict the future behaviour of dams as well as to select appropriate remedial measures. This paper provided details of a principal component analysis (PCA) used to investigate swelling and small irreversible displacements observed at the Daniel-Johnson dam in Quebec. PCA is a multivariate statistical method that performs the analysis of correlations or covariances between several random variables simultaneously. Three datasets were used: (1) reservoir water level; (2) air temperature; and (3) pendulum displacements. Standard linear regression analyses (HST) were performed for each variable in order to eliminate outliers and replace missing values. The multivariate dataset was then used to perform PCA on the entire dataset as well as on subsets from the original data. Displacement data from pendulums were used in the multivariate statistical analysis in which each component was treated as a separate variable. The comparison of irreversible displacements of the dam from HST analysis and principal component analysis (PCA) indicated that results were consistent with the data. The PCA analysis identified dominant patterns of behaviour and detected 2 distinct components of irreversible deformations arising from creep and swelling of concrete. Results of the study showed that the PCA analysis led to a better understanding of the overall behaviour of the dam and of individual arches and buttresses. It was concluded that the PCA analysis method will help to improve dam safety in addition to more accurately predicting the future behaviour of dams. 6 refs., 2 tabs., 9 figs.

  9. Density functional theory study of water interactions on Mn-doped CeO{sub 2}(1 1 1) surface

    Energy Technology Data Exchange (ETDEWEB)

    Pintos, Delfina García [Departamento de Ingeniería Química, Facultad de Ingeniería, Universidad de Buenos Aires, Pabellón de Industrias, Ciudad Universitaria, 1428 Capital Federal (Argentina); Juan, Alfredo [Departamento de Física and IFISUR, Universidad Nacional del Sur-CONICET, Avda. Alem 1253, 8000 Bahía Blanca (Argentina); Irigoyen, Beatriz, E-mail: beatriz@di.fcen.uba.ar [Departamento de Ingeniería Química, Facultad de Ingeniería, Universidad de Buenos Aires, Pabellón de Industrias, Ciudad Universitaria, 1428 Capital Federal (Argentina)

    2014-09-15

    Graphical abstract: - Highlights: • We studied geometric and electronic effects of water interactions on 12.5% Mn-doped CeO{sub 2}(1 1 1) surface through a spin-polarized DFT + U approach. • Water molecular and dissociative interactions were favored on Mn dopant compared to those on Ce sites. • Surface oxygen vacancies formation was not promoted by water adsorption. • OH species could attach on surface O-hole (left by surface oxygen remotion) causing important structural atomic relaxations, but without changing the oxidation state of Mn and Ce cations. - Abstract: Spin-polarized density functional theory (DFT + U) periodic calculations have been performed to study water adsorption and dissociation on the 12.5% Mn-doped CeO{sub 2}(1 1 1) surface. Our results indicated that Mn cation is the surface active site for water adsorption and dissociation reactions. The H{sub 2}O molecule preferably adsorbs on a Mn cation, causing some relaxation of the surface O-layer and, thus, facilitating the bonding of one of the H{sub H{sub 2O}} with the nearest oxygen atom. After overcoming an energy barrier of 0.46 eV, the water molecule could dissociate into OH and H species. The latter configuration is about 50% more exothermic than the molecular one, suggesting the Ce{sub 0.875}Mn{sub 0.125}O{sub 1.9375}(1 1 1) surface would be easily hydroxylated under reaction conditions. In addition, the calculations showed that water adsorption on the Mn-doped CeO{sub 2}(1 1 1) surface did not favor the creation of surface oxygen vacancies as it has been reported for pure CeO{sub 2}(1 1 1). On the other hand, we created a surface oxygen defect in the slab with structural oxygen vacancies and computed water interactions on the reduced surface. Although, the adsorption of OH species in the O-hole caused many surface and subsurface atomic displacements, no changes in the oxidation state of Mn and Ce cations were detected.

  10. Searching for Displaced Higgs Decays

    CERN Document Server

    Csaki, Csaba; Lombardo, Salvator; Slone, Oren

    2015-01-01

    We study a simplified model of the SM Higgs boson decaying to a degenerate pair of scalars which travel a macroscopic distance before decaying to SM particles. This is the leading signal for many well-motivated solutions to the hierarchy problem that do not propose additional light colored particles. Bounds for displaced Higgs decays below $10$ cm are found by recasting existing tracker searches from Run I. New tracker search strategies, sensitive to the characteristics of these models and similar decays, are proposed with sensitivities projected for Run II at $\\sqrt{s} = 13 $ TeV. With 20 fb$^{-1}$ of data, we find that Higgs branching ratios down to $7 \\times 10^{-4}$ can be probed for centimeter decay lengths.

  11. Loading functions for assessment of water pollution from nonpoint sources. Final report

    International Nuclear Information System (INIS)

    Methods for evaluating the quantity of water pollutants generated from nonpoint sources including agriculture, silviculture, construction, mining, runoff from urban areas and rural roads, and terrestrial disposal are developed and compiled for use in water quality planning. The loading functions, plus in some instances emission values, permit calculation of nonpoint source pollutants from available data and information. Natural background was considered to be a source and loading functions were presented to estimate natural or background loads of pollutants. Loading functions/values are presented for average conditions, i.e., annual average loads expressed as metric tons/hectare/year (tons/acre/year). Procedures for estimating seasonal or 30-day maximum and minimum loads are also presented. In addition, a wide variety of required data inputs to loading functions, and delineation of sources of additional information are included in the report. The report also presents an evaluation of limitations and constraints of various methodologies which will enable the user to employ the functions realistically

  12. Functional Abilities as a Predictor of Specific Motor Skills of Young Water Polo Players

    OpenAIRE

    Aleksandrovi?, Marko; Radovanovi?, Dragan; Oki?i?, Tomislav; Madi?, Dejan; Georgiev, Georgi

    2011-01-01

    The purpose of this study was to assess the influence of functional abilities on specificmotor skills. A total number of 92 male water polo players (age 12±0.5 years, body height 156.96±22.3 cm, body weight 51.02±33.18 kg) with at least two years’ experience, were enrolled in the study. The investigation protocol consisted of standardized anthropometric measurements, estimation of maximum oxygen uptake, determination of the lung function values, specific swim tests and swim tests with a ball....

  13. Ab-inito liquid water with hybrid functionals and dispersion interactions

    Science.gov (United States)

    Li, Zhaofeng; Wu, Xifan; Distasio, Robert, Jr.; Car, Roberto

    2012-02-01

    We report ab-initio molecular dynamics simulations of liquid water using the hybrid PBE0 functional plus self-consistent dispersion forces based on the scheme of Ref.ootnotetextA. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009). Simulations were performed at T=300K and at T=330K to approximately account for nuclear quantum effect on the oxygen-oxygen(O-O) RDF, as suggested by previous path integral simulations. Focusing on O-O RDF, we find that the combined effect of the hybrid functional and of the dispersion interactions significantly improves the agreement of the simulated structure with experiment.

  14. Do displaced workers lose occupational prestige?

    Science.gov (United States)

    Lippmann, Stephen; Rosenthal, Jeffrey E

    2008-06-01

    Worker displacement has become a common feature of employment in the "flexible economy." While studies of income losses and the duration of unemployment after displacement abound, and popular accounts argue that workers often lose status, less empirical attention has been paid to the quality or prestige of employment displaced workers are able to secure after a downsizing event. This paper helps to fill this gap in the literature by focusing on changes in occupational prestige among a nationally representative sample of displaced workers who became reemployed from the January 2004 Displaced Workers and Employee Tenure Supplement of the Current Population Survey. Our findings show that displaced workers with higher levels of education, net of other factors, fared significantly better than others in job quality upon reemployment, highlighting the importance of education in retaining status and privilege in the new economy. PMID:19069063

  15. How do hybrid functionals, dispersion interactions and quantum nuclei affect the structure of liquid water?

    Science.gov (United States)

    Li, Zhaofeng; Distasio, Robert A., Jr.; Car, Roberto; Wu, Xifan

    2011-03-01

    We report ab-initio molecular dynamics simulations of liquid water at STP and at the volume corresponding to experimental equilibrium density. These simulations are based on the hybrid functional PBE0 for the electrons and include approximate dispersion interactions according to Ref. Nuclear quantum corrections were included as estimated by Ref. We find that all of these components are important to significantly improve the agreement of the simulated structure with recent experimental analyses based on neutron and X-ray diffraction.

  16. Comparison of Geophysical Model Functions for SAR Wind Speed Retrieval in Japanese Coastal Waters

    OpenAIRE

    Merete Badger; Charlotte Bay Hasager; Katsutoshi Kozai; Yuko Takeyama; Teruo Ohsawa

    2013-01-01

    This work discusses the accuracies of geophysical model functions (GMFs) for retrieval of sea surface wind speed from satellite-borne Synthetic Aperture Radar (SAR) images in Japanese coastal waters characterized by short fetches and variable atmospheric stability conditions. In situ observations from two validation sites, Hiratsuka and Shirahama, are used for comparison of the retrieved sea surface wind speeds using CMOD (C-band model)4, CMOD_IFR2, CMOD5 and CMOD5.N. Of all the geophysical m...

  17. Simulation and Visualisation of Functional Landscapes: Effects of the Water Resource Competition between Plants

    OpenAIRE

    Le Chevalier, Vincent; Jaeger, Marc; Mei, Xing; Cournède, Paul-Henry

    2007-01-01

    Vegetation ecosystem simulation and visualisation are challenging topics involving multidisciplinary aspects. In this paper, we present a new generic frame for the simulation of natural phenomena through manageable and interacting models. It focuses on the functional growth of large vegetal ecosystems, showing coherence for scales ranging from the individual plant to communities and with a particular attention to the effects of water resource competition between plants. The proposed approach ...

  18. Three-dimensional linear fracture mechanics analysis by a displacement-hybrid finite-element model

    International Nuclear Information System (INIS)

    This paper deals with a finite-element procedures for the calculation of modes I, II and III stress intensity factors, which vary, along an arbitrarily curved three-dimensional crack front in a structural component. The finite-element model is based on a modified variational principle of potential energy with relaxed continuity requirements for displacements at the inter-element boundary. The variational principle is a three-field principle, with the arbitrary interior displacements for the element, interelement boundary displacements, and element boundary tractions as variables. The unknowns in the final algebraic system of equations, in the present displacement hybrid finite element model, are the nodal displacements and the three elastic stress intensity factors. Special elements, which contain proper square root and inverse square root crack front variations in displacements and stresses, respectively, are used in a fixed region near the crack front. Interelement displacement compatibility is satisfied by assuming an independent interelement boundary displacement field, and using a Lagrange multiplier technique to enforce such interelement compatibility. These Lagrangean multipliers, which are physically the boundary tractions, are assumed from an equilibrated stress field derived from three-dimensional Beltrami (or Maxwell-Morera) stress functions that are complete. However, considerable care should be exercised in the use of these stress functions such that the stresses produced by any of these stress function components are not linearly dependent

  19. Refractive index of water and steam as function of wavelength, temperature and density

    Science.gov (United States)

    Schiebener, P.; Straub, J.; Levelt Sengers, J. M. H.; Gallagher, J. S.

    1990-05-01

    Based on a comprehensive collection of data previously obtained by Thormählen et al. on the experimental refractive index of water and steam from the 1870s to the present, a new formulation is presented for the range of 0.2 to 2.5 ?m in wave-length, -10 to +500 °C in temperature and 0 to 1045 kg m-3 in density. The Lorentz-Lorentz function or molar refraction, a strong function of wavelength but only weakly dependent on density and temperature, is fitted to a selected set of accurate refractive index data. The NBS/NRC equation of state for water and steam, the new international standard, is used to convert the experimental pressures to density. The deviations of all experimental data from the formulation are shown. A detailed assessment of the accuracy of the formulation is presented. Although the formulation does not represent to within their accuracy the data from the best sets in the visible range for liquid water below the boiling point, we show that inconsistencies between data sets, and minor deficiencies of the equation of state, prevent further improvement of a formulation based on data over as wide a range as considered here. It is shown that the best refractive index data can be used to discriminate between the various formulations of the equation of state of water and steam. It is demonstrated that several recent formulations of optical properties of liquid water over large ranges of wavelength need improvement in the range covered here. The new formulation is used to generate tables of the refractive index of water and steam at six wavelengths in the visible, near-infrared and near-ultraviolet, from 0 to 500 °C and up to 100 MPa in pressure.

  20. Water transport and functional dynamics of aquaporins in osmoregulatory organs of fishes.

    Science.gov (United States)

    Madsen, Steffen S; Engelund, Morten B; Cutler, Christopher P

    2015-08-01

    Aquaporins play distinct roles for water transport in fishes as they do in mammals-both at the cellular, organ, and organismal levels. However, with over 32,000 known species of fishes inhabiting almost every aquatic environment, from tidal pools, small mountain streams, to the oceans and extreme salty desert lakes, the challenge to obtain consensus as well as specific knowledge about aquaporin physiology in these vertebrate clades is overwhelming. Because the integumental surfaces of these animals are in intimate contact with the surrounding milieu, passive water loss and uptake represent two of the major osmoregulatory challenges that need compensation. However, neither obligatory nor regulatory water transport nor their mechanisms have been elucidated to the same degree as, for example, ion transport in fishes. Currently fewer than 60 papers address fish aquaporins. Most of these papers identify "what is present" and describe tissue expression patterns in various teleosts. The agnathans, chondrichthyans, and functionality of fish aquaporins generally have received little attention. This review emphasizes the functional physiology of aquaporins in fishes, focusing on transepithelial water transport in osmoregulatory organs in euryhaline species - primarily teleosts, but covering other taxonomic groups as well. Most current knowledge comes from teleosts, and there is a strong need for related information on older fish clades. Our survey aims to stimulate new, original research in this area and to bring together new collaborations across disciplines. PMID:26338871

  1. Water Transport and Functional Dynamics of Aquaporins in Osmoregulatory Organs of Fishes

    DEFF Research Database (Denmark)

    Madsen, Steffen S; Engelund, Morten B

    2015-01-01

    Aquaporins play distinct roles for water transport in fishes as they do in mammals-both at the cellular, organ, and organismal levels. However, with over 32,000 known species of fishes inhabiting almost every aquatic environment, from tidal pools, small mountain streams, to the oceans and extreme salty desert lakes, the challenge to obtain consensus as well as specific knowledge about aquaporin physiology in these vertebrate clades is overwhelming. Because the integumental surfaces of these animals are in intimate contact with the surrounding milieu, passive water loss and uptake represent two of the major osmoregulatory challenges that need compensation. However, neither obligatory nor regulatory water transport nor their mechanisms have been elucidated to the same degree as, for example, ion transport in fishes. Currently fewer than 60 papers address fish aquaporins. Most of these papers identify "what is present" and describe tissue expression patterns in various teleosts. The agnathans, chondrichthyans, and functionality of fish aquaporins generally have received little attention. This review emphasizes the functional physiology of aquaporins in fishes, focusing on transepithelial water transport in osmoregulatory organs in euryhaline species - primarily teleosts, but covering other taxonomic groups as well. Most current knowledge comes from teleosts, and there is a strong need for related information on older fish clades. Our survey aims to stimulate new, original research in this area and to bring together new collaborations across disciplines.

  2. Light-induced effects on Brownian displacements

    Science.gov (United States)

    Bhalerao, Anish S.; Pollack, Gerald H.

    2011-01-01

    Earlier work on particles in aqueous solution indicated that particle hydration could be expanded by incident light. To assess the effects of expanded hydration we measured Brownian displacements of microspheres exposed to light of varying intensities and wavelengths. Displacements were consistently diminished in an intensity-dependent and wavelength-dependent fashion, and center-to-center distances between microspheres were shifted to higher values. We conclude that suspended microspheres are surrounded by hydration zones substantial enough to impact Brownian displacements. PMID:21287689

  3. Policies for displaced workers: An american perspective

    OpenAIRE

    O'Leary, Christopher J.

    2010-01-01

    American employment policy for displaced workers started in the Great Depression with programs for the employment service, unemployment insurance, work experience, and direct job creation. Assistance for workers displaced by foreign competition emerged in the 1960s along with formalized programs for occupational job skill training. The policy focus on displaced workers was sharpened in the 1980s through the Worker Adjustment and Retraining Notification Act and the Economic Dislocation and Wor...

  4. Unlocking protracted displacement: An Iraqi case study

    OpenAIRE

    Chatty, D; Mansour, N

    2011-01-01

    The displaced from Iraq now constitute one of the largest refugee populations worldwide manifesting the evolving conditions of "protracted displacement". Unlocking this protracted crisis of displacement requires analysis of the perceptions of solutions, durable and not-so-durable, among all stakeholders. This article focuses on the local-level perceptions of practitioners, policy-makers, and Iraqi refugees in Lebanon, Syria, and Jordan. It is based on desk research and interviews in the field...

  5. Measurements of water uptake of maize roots: the key function of lateral roots

    Science.gov (United States)

    Ahmed, M. A.; Zarebanadkouki, M.; Kroener, E.; Kaestner, A.; Carminati, A.

    2014-12-01

    Maize (Zea mays L.) is one of the most important crop worldwide. Despite its importance, there is limited information on the function of different root segments and root types of maize in extracting water from soils. Therefore, the aim of this study was to investigate locations of root water uptake in maize. We used neutron radiography to: 1) image the spatial distribution of maize roots in soil and 2) trace the transport of injected deuterated water (D2O) in soil and roots. Maizes were grown in aluminum containers (40×38×1 cm) filled with a sandy soil. When the plants were 16 days old, we injected D2O into selected soil regions containing primary, seminal and lateral roots. The experiments were performed during the day (transpiring plants) and night (not transpiring plants). The transport of D2O into roots was simulated using a new convection-diffusion numerical model of D2O transport into roots. By fitting the observed D2O transport we quantified the diffusional permeability and the water uptake of the different root segments. The maize root architecture consisted of a primary root, 4-5 seminal roots and many lateral roots connected to the primary and seminal roots. Laterals emerged from the proximal 15 cm of the primary and seminal roots. Water uptake occurred primarily in lateral roots. Lateral roots had the highest diffusional permeability (9.4×10-7), which was around six times higher that the diffusional permeability of the old seminal segments (1.4×10-7), and two times higher than the diffusional permeability of the young seminal segments (4.7×10-7). The radial flow of D2O into the lateral (6.7×10-5 ) was much higher than in the young seminal roots (1.1×10-12). The radial flow of D2O into the old seminal was negligible. We concluded that the function of the primary and seminal roots was to collect water from the lateral roots and transport it to the shoot. A maize root system with lateral roots branching from deep primary and seminal roots would be efficient in extracting water from the subsoil and better tolerate periods of water shortage. However, in this case the xylem axial resistance could be the limiting factor for the uptake of water.

  6. An interpretation of the symbolic function of Water Myth and itsmanifestations in Firdowsi’s Shahname based on mythological criticism

    Directory of Open Access Journals (Sweden)

    ????? ?????

    2013-01-01

    Full Text Available Mythological or archetypical criticism is an interdisciplinary approach which analyzes the literary text based on the findings of such sciences like psychology, anthropology, history of religion and history of civilization. In the present paper, the writers have studied the function of the aqueous archetype image in the myth of creation and the resulting mysteries in the context of mythological doctrines centered around Ferdowsi’s Shahnameh (Epic of Kings. Water myth, as one of the four contradictory elements forming the mythological material world, has assumed certain roles and is a common phenomenon in the world myths and Shahnameh. The symbolic functions of the water myth have been divided into three parts: 1. In different human cultures, the aqueous myth is a symbol of the beginning of material creation and life cycle in the universe. This function is symbolized in the primal creation of the world out of water and its symbolic end in it. 2. Water Myth is the main symbol of eternity and continuity of material life. This function is symbolized in the "life-sustaining water" and "the healing water". 3. The third function of Water Myth is manifested in the myth of passage through water (water test and symbolic washing by it (baptism myth; this is used as a test for the human catharsis, passage from a former stage into a new, exalted stage symbolized as the archetype of death and rebirth. Keywords: Water Myth, Four Elements, Mythological Criticism (Archetypical criticism, Archetype, Jung, Shahnameh

  7. Evaluation of Iodine and Water Co-adsorption on Silver-Functionalized Aerogel

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, B. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, S. H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Walker, J. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-30

    The co-adsorption of iodine and water on silver-functionalized silica aerogel was evaluated using research quantities of the aerogel prepared at Pacific Northwest National Laboratory. A macro thermogravimetric analyzer was used to measure weight changes in a thin bed of the aerogel as air streams containing moisture and/or iodine flowed through the bed. The total gas flow in all tests was adjusted to achieve a velocity of 10 m/min through the bed. Initial heating of the aerogel sample to 150°C in dry air (dew point < -60°C) resulted in weight loss on the order of 1 wt %. Because subsequent phases of the tests indicated that the aerogel did not sorb water, the weight loss was speculated to be caused by volatilization of material that may have been used in the manufacture of the aerogel. Follow-on tests are recommended to ascertain if the aerogel sorbs water at low temperatures, such as 25°C—this would help to determine if a manufacturing reagent is volatilized when raising the sample to iodine sorption temperatures (i.e., 150°C). Alternatively, the off-gas released upon heating could be condensed and analyzed. In tests using humidified air streams with dew points between -60°C and +10°C, the aerogel did not adsorb water at test temperatures of either 75°C or 150°C. Because water alone was not adsorbed, tests were performed to ascertain if iodine sorption varied between cases when nearly no water was present in the gas stream and when water was present. In one experiment, the gas stream consisted of dry air (dew point < -60°C) with an iodine concentration of 50 ppmv. In the other experiment, the gas stream consisted of air with a water dew point of 0°C and an iodine concentration of 50 ppmv. The ultimate weight gain was nearly the same in both experiments and was presumed to be due entirely to adsorption of iodine. However, a reduced rate of iodine uptake is indicated when water vapor is present. The reason for this is unclear. In both cases, purging the sample with dry, iodine-free air resulted in some weight loss (~2 wt %). It is recommended that the gas phase chemistry of the iodine–water system be reviewed to ascertain if iodine species that are less reactive with silver than molecular iodine are present; this could explain the reduced sorption rates when water is present. Further evaluation of the desorption is recommended, especially to determine how raising the temperature would affect desorption.

  8. Dielectric constant of water as a function of separation in a slab geometry: A molecular dynamics study

    Science.gov (United States)

    Itoh, Hidenosuke; Sakuma, Hiroshi

    2015-05-01

    Water in confining geometries shows various anomalous properties related to its structure and dynamics compared with bulk water. Here, the dielectric constant of water as a function of separation in a graphite slab geometry was studied using molecular dynamics simulations. The dielectric constants of water were calculated from the orientational polarization of water molecules when an external electric field was applied parallel and normal to the slabs. The reduction of the dielectric constant of water compared with bulk water can be explained by investigating the structure and dynamics of water in slab geometries. We found a preferred orientation of water molecules in the layer closest to the graphite surface. The self-diffusion coefficient distribution of water molecules along the direction normal to the slabs was also computed. Highly mobile water molecules in the intermediate region were generated by the weak hydrogen bonding produced by the preferred orientation of water molecules in the layer. We concluded that the dielectric constant of water in the slab geometry is lower than that of bulk water because of the reduction of the polarization of water and the highly mobile water molecules in the intermediate region arising from the preferred orientation of water molecules.

  9. Superhydrophilic molecularly imprinted polymers based on a water-soluble functional monomer for the recognition of gastrodin in water media.

    Science.gov (United States)

    Ji, Wenhua; Zhang, Mingming; Wang, Daijie; Wang, Xiao; Liu, Jianhua; Huang, Luqi

    2015-12-18

    In this study, the first successfully developed superhydrophilic molecularly imprinted polymers (MIPs) for gastrodin recognition have been described. MIPs were prepared via the bulk polymerization process in an aqueous solution using alkenyl glycosides glucose (AGG) as the water-soluble functional monomer. The non-imprinted polymers (NIPs) were also synthesized using the same method without the use of the template. The dynamic water contact angles and photographs of the dispersion properties confirmed that the molecularly imprinted polymers displayed excellent superhydrophilicity. The results demonstrated that the MIPs exhibited high selectivity and an excellent imprinting effect. A molecularly imprinted solid phase extraction (MISPE) method was established. Optimization of various parameters affecting MISPE was investigated. Under the optimized conditions, a wide linear range (0.001-100.0?gmL(-1)) and low limits of detection (LOD) and quantification (LOQ) (0.03 and 0.09ngmL(-1), respectively) were achieved. When compared with the NIPs, higher recoveries (90.5% to 97.6%) of gastrodin with lower relative standard deviations values (below 6.4%) using high performance liquid chromatography were obtained at three spiked levels in three blank samples. These results demonstrated one efficient, highly selective and environmentally-friendly MISPE technique with excellent reproducibility for the purification and pre-concentration of gastrodin from an aqueous extract of Gastrodia elata roots. PMID:26627582

  10. Sub-stoichiometric functionally graded titania fibres for water-splitting applications

    Science.gov (United States)

    Adamaki, Vaia; Sergejevs, A.; Clarke, C.; Clemens, F.; Marken, F.; Bowen, C. R.

    2015-06-01

    The photo-electro-chemical (PEC) splitting of water requires semiconductor materials with a minimum energy gap of 1.23 eV along with conduction and valence bands overlapping the oxidation of H2O and reduction of H+ respectively. This work overcomes the limitations of stoichiometric titania by manufacturing fine scale fibres that exhibit a compositional gradient of oxygen vacancies across the fibre length. In such a fibre configuration the fibre end that is chemically reduced to a relatively small extent performs as the photoanode and the oxygen vacancies enhance the absorption of light. The fibre end that is reduced the most consists of Magnéli phases and exhibits metallic electrical conductivity that enhances the electron-hole separation. The structure and composition of the functionally graded fibres, which were manufactured through extrusion, pressureless sintering and carbo-thermal reduction, are studied using XRD and electron microscopy. Electrochemical impedance spectroscopy measurements were performed in a three-electrode electrochemical system and showed that the oxygen vacancies in the functionally graded fibres affect the flat band potential and have increased carrier density. The efficiency of the system was evaluated with PEC measurements that shows higher efficiency for the functionally graded fibres compared to homogeneous TiO2 or Magnéli phase fibres. The functionally graded and fine scale fibres have the potential to be used as an array of active fibres for water splitting applications.

  11. Water Processable Polythiophene Nanowires by Photo-Cross-Linking and Click-Functionalization.

    Science.gov (United States)

    Kim, Hyeong Jun; Skinner, Matthew; Yu, Hojeong; Oh, Joon Hak; Briseno, Alejandro L; Emrick, Todd; Kim, Bumjoon J; Hayward, Ryan C

    2015-09-01

    Replacing or minimizing the use of halogenated organic solvents in the processing and manufacturing of conjugated polymer-based organic electronics has emerged as an important issue due to concerns regarding toxicity, environmental impact, and high cost. To date, however, the processing of well-ordered conjugated polymer nanostructures has been difficult to achieve using environmentally benign solvents. In this work, we report the development of water and alcohol processable nanowires (NWs) with well-defined crystalline nanostructure based on the solution assembly of azide functionalized poly(3-hexylthiophene) (P3HT-azide) and subsequent photo-cross-linking and functionalization of these NWs. The solution-assembled P3HT-azide NWs were successfully cross-linked by exposure to UV light, yielding good thermal and chemical stability. Residual azide units on the photo-cross-linked NWs were then functionalized with alkyne terminated polyethylene glycol (PEG-alkyne) using copper catalyzed azide-alkyne cycloaddition chemistry. PEG functionalization of the cross-linked P3HT-azide NWs allowed for stable dispersion in alcohols and water, while maintaining well-ordered NW structures with electronic properties suitable for the fabrication of organic field effect transistors (OFETs). PMID:26289785

  12. Diversity and functions of bacterial community in drinking water biofilms revealed by high-throughput sequencing

    Science.gov (United States)

    Chao, Yuanqing; Mao, Yanping; Wang, Zhiping; Zhang, Tong

    2015-06-01

    The development of biofilms in drinking water (DW) systems may cause various problems to water quality. To investigate the community structure of biofilms on different pipe materials and the global/specific metabolic functions of DW biofilms, PCR-based 454 pyrosequencing data for 16S rRNA genes and Illumina metagenomic data were generated and analysed. Considerable differences in bacterial diversity and taxonomic structure were identified between biofilms formed on stainless steel and biofilms formed on plastics, indicating that the metallic materials facilitate the formation of higher diversity biofilms. Moreover, variations in several dominant genera were observed during biofilm formation. Based on PCA analysis, the global functions in the DW biofilms were similar to other DW metagenomes. Beyond the global functions, the occurrences and abundances of specific protective genes involved in the glutathione metabolism, the SoxRS system, the OxyR system, RpoS regulated genes, and the production/degradation of extracellular polymeric substances were also evaluated. A near-complete and low-contamination draft genome was constructed from the metagenome of the DW biofilm, based on the coverage and tetranucleotide frequencies, and identified as a Bradyrhizobiaceae-like bacterium according to a phylogenetic analysis. Our findings provide new insight into DW biofilms, especially in terms of their metabolic functions.

  13. Displacement of Monolithic Rubble-Mound Breakwater Crown-Walls

    DEFF Research Database (Denmark)

    NØrgaard, JØrgen Harck; Andersen, Lars Vabbersgaard

    2012-01-01

    This paper evaluates the validity of a simple one-dimensional dynamic analysis as well as a Finite-Element model to determine the sliding of a rubble-mound breakwater crown-wall. The evaluation is based on a case example with real wave load time-series and displacements measured from two-dimensional physical model tests. The outcome is a more reliable evaluation of the applicability of simple dynamic calculations for the estimation of displacement of rubble-mound superstructures. The case example clearly demonstrates that a simplified one-dimensional sliding model provides a safe estimate of the accumulated sliding distance of crown-wall superstructures, which is in contrast to findings from previous similar studies on caisson breakwaters. The calculated sliding distance is approximately three times larger than the measured one when using the original one-dimensional model suggested in previous studies on caisson breakwaters, but correction terms are suggested in the present paper to obtain almost equal measured and estimated displacements. This is of great practical importance since many existing rubble-mound crown-walls are subjected to increasing wave loads due to rising sea water level from climate changes. Reliable and safe estimates are needed to determine whether displacements of crown wall superstructures during extreme situations would be acceptable or whether they lead to total failure of the structures.

  14. Lung function in subjects exposed to crude oil spill into sea water

    Energy Technology Data Exchange (ETDEWEB)

    Meo, Sultan Ayoub [Department of Physiology, College of Medicine, King Saud University, P.O. Box 2925, Riyadh 11461 (Saudi Arabia)], E-mail: sultanmeo@hotmail.com; Al-Drees, Abdul Majeed [Department of Physiology, College of Medicine, King Saud University, P.O. Box 2925, Riyadh 11461 (Saudi Arabia); Meo, Imran M.U. [Hamdard College of Medicine and Dentistry, Hamdard University, Karachi (Pakistan); Al-Saadi, Muslim M. [Department of Pediatrics, College of Medicine, King Saud University, Riyadh (Saudi Arabia); Azeem, Muhammad Abdul [Department of Physiology, Ummal Qura University, Mecca (Saudi Arabia)

    2008-01-15

    A Greek oil-tanker ran aground, resulting in a huge oil spill along the costal areas of Karachi, Pakistan. The purpose of this study was to assess the lung function and follow up change after one year in subjects exposed to crude oil spill in sea water. It was a cross sectional study with follow up in 20 apparently healthy, non-smoking, male workers, who were exposed to a crude oil spill environment during oil cleaning operation. The exposed group was matched with 31 apparently healthy male control subjects. Pulmonary function test was performed using an electronic Spirometer. Subjects exposed to polluted air have significant reduction in forced vital capacity (FVC), forced expiratory volume in first second (FEV{sub 1}), forced expiratory flow (FEF{sub 25-75%}) and maximum voluntary ventilation (MVV) compared to their matched controls. This impairment was reversible and lung functions parameters were improved when the subjects were withdrawn from the polluted air environment.

  15. Water

    Science.gov (United States)

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  16. Improving the controlled release of water-insoluble emodin from amino-functionalized mesoporous silica

    International Nuclear Information System (INIS)

    Several types of amino-functionalized mesoporous silica, including F5-SBA-15, F10-SBA-15, and F15-SBA-15 were prepared through co-condensation of tetraethoxysilane (TEOS) and (3-aminopropyl)triethoxysilane (APTES) in varying molar ratios (5 mol%, 10 mol%, and 15 mol%) via a hydrothermal process. The materials obtained were characterized by means of small-angle X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption, Fourier transformed infrared spectra, and X-ray photoelectron spectroscopy. Increasing APTES molar ratios decreased the degree of orderliness of the functionalized mesoporous silica. Pure and amino-functionalized SBA-15 samples were employed as supports for the controlled release of water-insoluble drug emodin. Loading experiments showed that drug loading capacities mainly depended on the surface areas and pore diameters of the carriers. Controlled release profiles of emodin-loaded samples were studied in phosphate buffered saline (PBS, pH 7.4), and results indicated that the emodin release rate could be controlled by surface amino-functionalized carriers. Emodin loaded on functionalized mesoporous supports exhibited a lower release rate than that of loaded on pure SBA-15, emodin loaded on F10-SBA-15 showed the smallest release amount (71.74 wt%) after stirring in PBS for 60 h. Findings suggest that functionalized mesoporous SBA-15 is a promising carrier for achieving prolonged release time periods.

  17. Benefit of warm water immersion on biventricular function in patients with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Kardassis Dimitris

    2009-07-01

    Full Text Available Abstract Background Regular physical activity and exercise are well-known cardiovascular protective factors. Many elderly patients with heart failure find it difficult to exercise on land, and hydrotherapy (training in warm water could be a more appropriate form of exercise for such patients. However, concerns have been raised about its safety. The aim of this study was to investigate, with echocardiography and Doppler, the acute effect of warm water immersion (WWI and effect of 8 weeks of hydrotherapy on biventricular function, volumes and systemic vascular resistance. A secondary aim was to observe the effect of hydrotherapy on brain natriuretic peptide (BNP. Methods Eighteen patients [age 69 ± 8 years, left ventricular ejection fraction 31 ± 9%, peakVO2 14.6 ± 4.5 mL/kg/min] were examined with echocardiography on land and in warm water (34°C. Twelve of these patients completed 8 weeks of control period followed by 8 weeks of hydrotherapy twice weekly. Results During acute WWI, cardiac output increased from 3.1 ± 0.8 to 4.2 ± 0.9 L/min, LV tissue velocity time integral from 1.2 ± 0.4 to 1.7 ± 0.5 cm and right ventricular tissue velocity time integral from 1.6 ± 0.6 to 2.5 ± 0.8 cm (land vs WWI, p There was no change in the cardiovascular response or BNP after 8 weeks of hydrotherapy. Conclusion Hydrotherapy was well tolerated by all patients. The main observed cardiac effect during acute WWI was a reduction in heart rate, which, together with a decrease in afterload, resulted in increases in systolic and diastolic biventricular function. Although 8 weeks of hydrotherapy did not improve cardiac function, our data support the concept that exercise in warm water is an acceptable regime for patients with heart failure.

  18. Effects of Fault Displacement on Emplacement Drifts

    International Nuclear Information System (INIS)

    The purpose of this analysis is to evaluate potential effects of fault displacement on emplacement drifts, including drip shields and waste packages emplaced in emplacement drifts. The output from this analysis not only provides data for the evaluation of long-term drift stability but also supports the Engineered Barrier System (EBS) process model report (PMR) and Disruptive Events Report currently under development. The primary scope of this analysis includes (1) examining fault displacement effects in terms of induced stresses and displacements in the rock mass surrounding an emplacement drift and (2 ) predicting fault displacement effects on the drip shield and waste package. The magnitude of the fault displacement analyzed in this analysis bounds the mean fault displacement corresponding to an annual frequency of exceedance of 10-5 adopted for the preclosure period of the repository and also supports the postclosure performance assessment. This analysis is performed following the development plan prepared for analyzing effects of fault displacement on emplacement drifts (CRWMS M and O 2000). The analysis will begin with the identification and preparation of requirements, criteria, and inputs. A literature survey on accommodating fault displacements encountered in underground structures such as buried oil and gas pipelines will be conducted. For a given fault displacement, the least favorable scenario in term of the spatial relation of a fault to an emplacement drift is chosen, and the analysis is then performed analytically. Based on the analysis results, conclusions are made regarding the effects and consequences of fault displacement on emplacement drifts. Specifically, the analysis will discuss loads which can be induced by fault displacement on emplacement drifts, drip shield and/or waste packages during the time period of postclosure

  19. Immersion freezing of water and aqueous ammonium sulphate droplets initiated by Humic Like Substances as a function of water activity

    Directory of Open Access Journals (Sweden)

    Y. J. Rigg

    2013-02-01

    Full Text Available Immersion freezing of water and aqueous (NH42SO4 droplets containing Leonardite (LEO and Pahokee peat (PP serving as surrogates for Humic Like Substances (HULIS has been investigated. Organic aerosol containing HULIS are ubiquitous in the atmosphere, however, their potential for ice cloud formation is uncertain. Immersion freezing has been studied for temperatures as low as 215 K and solution water activity, aw, from 0.85–1.0. The freezing temperatures of water and aqueous solution droplets containing LEO and PP are 5–15 K warmer than homogeneous ice nucleation temperatures. Heterogeneous freezing temperatures can be represented by a horizontal shift of the ice melting curve as a function of solution aw, ?aw, by 0.2703 and 0.2466, respectively. Corresponding heterogeneous ice nucleation rate coefficients, Jhet, are (9.6 ± 2.5×104 and (5.4 ± 1.4×104 cm?2 s?1 for LEO and PP containing droplets, respectively, and remain constant along freezing curves characterized by ?aw. Consequently predictions of freezing temperatures and kinetics can be made without knowledge of the solute type when relative humidity and IN surface areas are known. The acquired ice nucleation data are applied to evaluate different approaches to fit and reproduce experimentally derived frozen fractions. In addition, we apply a basic formulation of classical nucleation theory (?(T-model to calculate contact angles and frozen fractions. Contact angles calculated for each ice nucleus as a function of temperature, ?(T-model, reproduce exactly experimentally derived frozen fractions without involving free fit parameters. However, assigning the IN a single contact angle for entire population (single-? model is not suited to represent the frozen fractions. Application of ?-PDF, active sites, and deterministic model approaches to measured frozen fractions yield similar good representations. Thus, from fitting frozen fractions only, the underlying ice nucleation mechanism and nature of the ice nucleating sites cannot be inferred. In contrast to using fitted functions obtained to represent experimental conditions only, we suggest to use experimentally derived Jhet as a function of temperature and aw that can be applied to conditions outside of those probed in laboratory. This is because Jhet(T is independent of time and IN surface areas in contrast to the fit parameters obtained by representation of experimentally derived frozen fractions.

  20. Omnidirectional displacements for deformable surfaces.

    Science.gov (United States)

    Kainmueller, Dagmar; Lamecker, Hans; Heller, Markus O; Weber, Britta; Hege, Hans-Christian; Zachow, Stefan

    2013-05-01

    Deformable surface models are often represented as triangular meshes in image segmentation applications. For a fast and easily regularized deformation onto the target object boundary, the vertices of the mesh are commonly moved along line segments (typically surface normals). However, in case of high mesh curvature, these lines may not intersect with the target boundary at all. Consequently, certain deformations cannot be achieved. We propose omnidirectional displacements for deformable surfaces (ODDS) to overcome this limitation. ODDS allow each vertex to move not only along a line segment but within the volumetric inside of a surrounding sphere, and achieve globally optimal deformations subject to local regularization constraints. However, allowing a ball-shaped instead of a linear range of motion per vertex significantly increases runtime and memory. To alleviate this drawback, we propose a hybrid approach, fastODDS, with improved runtime and reduced memory requirements. Furthermore, fastODDS can also cope with simultaneous segmentation of multiple objects. We show the theoretical benefits of ODDS with experiments on synthetic data, and evaluate ODDS and fastODDS quantitatively on clinical image data of the mandible and the hip bones. There, we assess both the global segmentation accuracy as well as local accuracy in high curvature regions, such as the tip-shaped mandibular coronoid processes and the ridge-shaped acetabular rims of the hip bones. PMID:23523192

  1. Optical measurement of large transient mechanical displacements

    International Nuclear Information System (INIS)

    A simple method suitable for extracting large mechanical displacements from the phase modulation of an optical beam reflected from the moving surface is presented. In the MHz range, transient displacements larger than 1 ?m have been measured with a standard heterodyne interferometer. Copyright 2001 American Institute of Physics

  2. Displacement Sensor Using A Compensated Fibre Link

    Science.gov (United States)

    Davies, D. E. N.; Chaimowicz, J.; Economou, G.; Foley, J.

    1984-11-01

    The paper describes a remote (intensity based) displacement or pressure sensor. It includes work on a scheme for compensating variations in optical power, receiver sensitivity and fibre transmission loss in addition to tarnishing of the displacement (pressure) diaphragm. Results are presented for a prototype (uncompensated) sensor plus laboratory results for the compensated scheme.

  3. Young Children's Understanding of Displaced Aggression.

    Science.gov (United States)

    Weiss, Michael G.; Miller, Patricia H.

    1983-01-01

    Examines early phases of understanding of causes of moderately and extremely displaced aggression. Preschool and kindergarten children three to five years of age viewed eight videotaped episodes of displaced aggression. Comprehension was assessed by means of open-ended questions and forced-choice picture selections. (Author/RH)

  4. Video Games, Adolescents, and the Displacement Effect

    Science.gov (United States)

    Fisher, Carla Christine

    2012-01-01

    The displacement effect (the idea that time spent in one activity displaces time spent in other activities) was examined within the lens of adolescents' video game use and their time spent reading, doing homework, in physically active sports and activities, in creative play, and with parents and friends. Data were drawn from the Panel Study…

  5. Unusual renal displacement due to massive splenomegaly

    International Nuclear Information System (INIS)

    Report of a case of unusual renal displacement due to massive splenomegaly. The left kidney was displaced upwards by massive enlargement of the spleen. The own findings of ultrasonography, abdominal computed tomography and intravenous urogram are described and compared with the findings in the literature. (orig.)

  6. Intramolecular cyclization of aspartic acid residues assisted by three water molecules: a density functional theory study

    International Nuclear Information System (INIS)

    Aspartic acid (Asp) residues in peptides and proteins (l-Asp) are known to undergo spontaneous nonenzymatic reactions to form l-?-Asp, d-Asp, and d-?-Asp residues. The formation of these abnormal Asp residues in proteins may affect their three-dimensional structures and hence their properties and functions. Indeed, the reactions have been thought to contribute to aging and pathologies. Most of the above reactions of the l-Asp residues proceed via a cyclic succinimide intermediate. In this paper, a novel three-water-assisted mechanism is proposed for cyclization of an Asp residue (forming a gem-diol precursor of the succinimide) by the B3LYP/6-31 + G(d,p) density functional theory calculations carried out for an Asp-containing model compound (Ace?Asp?Nme, where Ace = acetyl and Nme = NHCH3). The three water molecules act as catalysts by mediating ‘long-range’ proton transfers. In the proposed mechanism, the amide group on the C-terminal side of the Asp residue is first converted to the tautomeric iminol form (iminolization). Then, reorientation of a water molecule and a conformational change occur successively, followed by the nucleophilic attack of the iminol nitrogen on the carboxyl carbon of the Asp side chain to form the gem-diol species. A satisfactory agreement was obtained between the calculated and experimental energetics.

  7. Intramolecular cyclization of aspartic acid residues assisted by three water molecules: a density functional theory study

    Science.gov (United States)

    Takahashi, Ohgi; Kirikoshi, Ryota

    2014-01-01

    Aspartic acid (Asp) residues in peptides and proteins (l-Asp) are known to undergo spontaneous nonenzymatic reactions to form l-?-Asp, d-Asp, and d-?-Asp residues. The formation of these abnormal Asp residues in proteins may affect their three-dimensional structures and hence their properties and functions. Indeed, the reactions have been thought to contribute to aging and pathologies. Most of the above reactions of the l-Asp residues proceed via a cyclic succinimide intermediate. In this paper, a novel three-water-assisted mechanism is proposed for cyclization of an Asp residue (forming a gem-diol precursor of the succinimide) by the B3LYP/6-31 + G(d,p) density functional theory calculations carried out for an Asp-containing model compound (Ace-Asp-Nme, where Ace = acetyl and Nme = NHCH3). The three water molecules act as catalysts by mediating ‘long-range’ proton transfers. In the proposed mechanism, the amide group on the C-terminal side of the Asp residue is first converted to the tautomeric iminol form (iminolization). Then, reorientation of a water molecule and a conformational change occur successively, followed by the nucleophilic attack of the iminol nitrogen on the carboxyl carbon of the Asp side chain to form the gem-diol species. A satisfactory agreement was obtained between the calculated and experimental energetics.

  8. Hydrated goethite (alpha-FeOOH) (100) interface structure: Ordered water and surface functional groups.

    Energy Technology Data Exchange (ETDEWEB)

    Ghose, S.K.; Waychunas, G.A.; Trainor, T.P.; Eng, P.J.

    2009-12-15

    Goethite({alpha}-FeOOH), an abundant and highly reactive iron oxyhydroxide mineral, has been the subject of numerous stud-ies of environmental interface reactivity. However, such studies have been hampered by the lack of experimental constraints on aqueous interface structure, and especially of the surface water molecular arrangements. Structural information of this type is crucial because reactivity is dictated by the nature of the surface functional groups and the structure or distribution of water and electrolyte at the solid-solution interface. In this study we have investigated the goethite(100) surface using surface diffraction techniques, and have determined the relaxed surface structure, the surface functional groups, and the three dimensional nature of two distinct sorbed water layers. The crystal truncation rod (CTR) results show that the interface structure consists of a double hydroxyl, double water terminated interface with significant atom relaxations. Further, the double hydroxyl terminated surface dominates with an 89% contribution having a chiral subdomain structure on the(100) cleavage faces. The proposed interface stoichiometry is ((H{sub 2}O)-(H{sub 2}O)-OH{sub 2}-OH-Fe-O-O-Fe-R) with two types of terminal hydroxyls; a bidentate (B-type) hydroxo group and a monodentate (A-type) aquo group. Using the bond-valence approach the protonation states of the terminal hydroxyls are predicted to be OH type (bidentate hydroxyl with oxygen coupled to two Fe{sup 3+} ions) and OH{sub 2} type (monodentate hydroxyl with oxygen tied to only one Fe{sup 3+}). A double layer three dimensional ordered water structure at the interface was determined from refinement of fits to the experimental data. Application of bond-valence constraints to the terminal hydroxyls with appropriate rotation of the water dipole moments allowed a plausible dipole orientation model as predicted. The structural results are discussed in terms of protonation and H-bonding at the interface, and the results provide an ideal basis for testing theoretical predictions of characteristic surface properties such as pK{sub a}, sorption equilibria, and surface water permittivity.

  9. Accuracy enhancement of point triangulation probes for linear displacement measurement

    Science.gov (United States)

    Kim, Kyung-Chan; Kim, Jong-Ahn; Oh, SeBaek; Kim, Soo Hyun; Kwak, Yoon Keun

    2000-03-01

    Point triangulation probes (PTBs) fall into a general category of noncontact height or displacement measurement devices. PTBs are widely used for their simple structure, high resolution, and long operating range. However, there are several factors that must be taken into account in order to obtain high accuracy and reliability; measurement errors from inclinations of an object surface, probe signal fluctuations generated by speckle effects, power variation of a light source, electronic noises, and so on. In this paper, we propose a novel signal processing algorithm, named as EASDF (expanded average square difference function), for a newly designed PTB which is composed of an incoherent source (LED), a line scan array detector, a specially selected diffuse reflecting surface, and several optical components. The EASDF, which is a modified correlation function, is able to calculate displacement between the probe and the object surface effectively even if there are inclinations, power fluctuations, and noises.

  10. Gas phase dispersion in compost as a function of different water contents and air flow rates

    Science.gov (United States)

    Sharma, Prabhakar; Poulsen, Tjalfe G.

    2009-07-01

    Gas phase dispersion in a natural porous medium (yard waste compost) was investigated as a function of gas flow velocity and compost volumetric water content using oxygen and nitrogen as tracer gases. The compost was chosen because it has a very wide water content range and because it represents a wide range of porous media, including soils and biofilter media. Column breakthrough curves for oxygen and nitrogen were measured at relatively low pore gas velocities, corresponding to those observed in for instance soil vapor extraction systems or biofilters for air cleaning at biogas plants or composting facilities. Total gas mechanical dispersion-molecular diffusion coefficients were fitted from the breakthrough curves using a one-dimensional numerical solution to the advection-dispersion equation and used to determine gas dispersivities at different volumetric gas contents. The results showed that gas mechanical dispersion dominated over molecular diffusion with mechanical dispersion for all water contents and pore gas velocities investigated. Importance of mechanical dispersion increased with increasing pore gas velocity and compost water content. The results further showed that gas dispersivity was relatively constant at high values of compost gas-filled porosity but increased with decreasing gas-filled porosity at lower values of gas-filled porosity. Results finally showed that measurement uncertainty in gas dispersivity is generally highest at low values of pore gas velocity.

  11. Water plasma functionalized CNTs/MnO2 composites for supercapacitors.

    Science.gov (United States)

    Hussain, Shahzad; Amade, Roger; Jover, Eric; Bertran, Enric

    2013-01-01

    A water plasma treatment applied to vertically-aligned multiwall carbon nanotubes (CNTs) synthesized by plasma enhanced chemical vapour deposition gives rise to surface functionalization and purification of the CNTs, along with an improvement of their electrochemical properties. Additional increase of their charge storage capability is achieved by anodic deposition of manganese dioxide lining the surface of plasma-treated nanotubes. The morphology (nanoflower, layer, or needle-like structure) and oxidation state of manganese oxide depend on the voltage window applied during charge-discharge measurements and are found to be key points for improved efficiency of capacitor devices. MnO2/CNTs nanocomposites exhibit an increase in their specific capacitance from 678?Fg(-1), for untreated CNTs, up to 750?Fg(-1), for water plasma-treated CNTs. PMID:24348189

  12. A hybrid model for river water temperature as a function of air temperature and discharge

    Science.gov (United States)

    Toffolon, Marco; Piccolroaz, Sebastiano

    2015-11-01

    Water temperature controls many biochemical and ecological processes in rivers, and theoretically depends on multiple factors. Here we formulate a model to predict daily averaged river water temperature as a function of air temperature and discharge, with the latter variable being more relevant in some specific cases (e.g., snowmelt-fed rivers, rivers impacted by hydropower production). The model uses a hybrid formulation characterized by a physically based structure associated with a stochastic calibration of the parameters. The interpretation of the parameter values allows for better understanding of river thermal dynamics and the identification of the most relevant factors affecting it. The satisfactory agreement of different versions of the model with measurements in three different rivers (root mean square error smaller than 1oC, at a daily timescale) suggests that the proposed model can represent a useful tool to synthetically describe medium- and long-term behavior, and capture the changes induced by varying external conditions.

  13. A displacement formulation for cylindrical shells under radial loads

    OpenAIRE

    Madureira, Luísa; Fonseca, E.M.M. (Coord.); Barros, Rui Carneiro de

    2013-01-01

    A displacement formulation for cylindrical shells subjected to radial loads is presented. Static loads are applied to straight thin pipes using a variational method and results are compared both to finite element analysis and a shell element from Ansys program. The formulation includes a combination of trigonometric functions in two variables, longitudinal and circumferential direction. Then a system of differential equations is solved for two different load cases and the vertical displacemen...

  14. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    Directory of Open Access Journals (Sweden)

    J. Moeys

    2012-07-01

    Full Text Available Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisations usually rely on a set of lookup tables and (pedotransfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accounts for preferential flow in soil macropores. We used tracer monitoring data from 16 lysimeter studies, carried out in three European countries, to evaluate the ability of MACRO and this "blind parameterisation" scheme to reproduce measured solute leaching at the base of each lysimeter. We focused on the prediction of early tracer breakthrough due to preferential flow, because this is critical for pesticide leaching. We then calibrated a selected number of parameters in order to assess to what extent the prediction of water and solute leaching could be improved.

    Our results show that water flow was generally reasonably well predicted (median model efficiency, ME, of 0.42. Although the general pattern of solute leaching was reproduced well by the model, the overall model efficiency was low (median ME = ?0.26 due to errors in the timing and magnitude of some peaks. Preferential solute leaching at early pore volumes was also systematically underestimated. Nonetheless, the ranking of soils according to solute loads at early pore volumes was reasonably well estimated (concordance correlation coefficient, CCC, between 0.54 and 0.72. Moreover, we also found that ignoring macropore flow leads to a significant deterioration in the ability of the model to reproduce the observed leaching pattern, and especially the early breakthrough in some soils. Finally, the calibration procedure showed that improving the estimation of solute transport parameters is probably more important than the estimation of water flow parameters. Overall, the results are encouraging for the use of this modelling set-up to estimate pesticide leaching risks at the regional-scale, especially where the objective is to identify vulnerable soils and "source" areas of contamination.

  15. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    Science.gov (United States)

    Moeys, J.; Larsbo, M.; Bergström, L.; Brown, C. D.; Coquet, Y.; Jarvis, N. J.

    2012-07-01

    Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisations usually rely on a set of lookup tables and (pedo)transfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accounts for preferential flow in soil macropores. We used tracer monitoring data from 16 lysimeter studies, carried out in three European countries, to evaluate the ability of MACRO and this "blind parameterisation" scheme to reproduce measured solute leaching at the base of each lysimeter. We focused on the prediction of early tracer breakthrough due to preferential flow, because this is critical for pesticide leaching. We then calibrated a selected number of parameters in order to assess to what extent the prediction of water and solute leaching could be improved. Our results show that water flow was generally reasonably well predicted (median model efficiency, ME, of 0.42). Although the general pattern of solute leaching was reproduced well by the model, the overall model efficiency was low (median ME = -0.26) due to errors in the timing and magnitude of some peaks. Preferential solute leaching at early pore volumes was also systematically underestimated. Nonetheless, the ranking of soils according to solute loads at early pore volumes was reasonably well estimated (concordance correlation coefficient, CCC, between 0.54 and 0.72). Moreover, we also found that ignoring macropore flow leads to a significant deterioration in the ability of the model to reproduce the observed leaching pattern, and especially the early breakthrough in some soils. Finally, the calibration procedure showed that improving the estimation of solute transport parameters is probably more important than the estimation of water flow parameters. Overall, the results are encouraging for the use of this modelling set-up to estimate pesticide leaching risks at the regional-scale, especially where the objective is to identify vulnerable soils and "source" areas of contamination.

  16. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    Directory of Open Access Journals (Sweden)

    J. Moeys

    2012-02-01

    Full Text Available Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisation usually rely on a set of lookup tables and (pedotransfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accounts for preferential flow in soil macropores. We used tracer monitoring data from 16 lysimeter studies, carried out in three European countries, to evaluate the ability of MACRO and this "blind parameterisation" scheme to reproduce measured solute leaching at the base of each lysimeter. We focused on the prediction of early tracer breakthrough due to preferential flow, because this is critical for pesticide leaching. We then calibrated a selected number of parameters in order to assess to what extent the prediction of water and solute leaching could be improved.

    Our results show that water flow was generally reasonably well predicted (median model efficiency, ME, of 0.42. Although the general pattern of solute leaching was reproduced well by the model, the overall model efficiency was low (median ME = ?0.26 due to errors in the timing and magnitude of some peaks. Preferential solute leaching at early pore volumes was also systematically underestimated. Nonetheless, the ranking of soils according to solute loads at early pore volumes was reasonably well estimated (concordance correlation coefficient, CCC, between 0.54 and 0.72. Moreover, we also found that ignoring macropore flow leads to a significant deterioration in the ability of the model to reproduce the observed leaching pattern, and especially the early breakthrough in some soils. Finally, the calibration procedure showed that improving the estimation of solute transport parameters is probably more important than the estimation of water flow parameters. Overall, the results are encouraging for the use of this modelling set-up to estimate pesticide leaching risks at the regional-scale, especially where the objective is to identify vulnerable soils and "source" areas of contamination.

  17. Graphene on ferromagnetic surfaces and its functionalization with water and ammonia

    OpenAIRE

    Voloshina Elena; Paulus Beate; Böttcher Stefan; Weser Martin; Dedkov Yuriy; Horn Karsten

    2011-01-01

    Abstract In this article, an angle-resolved photoelectron spectroscopy (ARPES), X-ray absorption spectroscopy (XAS), and density-functional theory (DFT) investigations of water and ammonia adsorption on graphene/Ni(111) are presented. The results of adsorption on graphene/Ni(111) obtained in this study reveal the existence of interface states, originating from the strong hybridization of the graphene ? and spin-polarized Ni 3d valence band states. ARPES and XAS data of the H2O (NH3)/grap...

  18. Density functional for van der Waals forces accounts for hydrogen bond in benchmark set of water hexamers

    DEFF Research Database (Denmark)

    Kelkkanen, Kari André; Lundqvist, Bengt; Nørskov, Jens Kehlet

    2009-01-01

    A recent extensive study has investigated how various exchange-correlation (XC) functionals treat hydrogen bonds in water hexamers and has shown traditional generalized gradient approximation and hybrid functionals used in density-functional (DF) theory to give the wrong dissociation-energy trend of low-lying isomers and van der Waals (vdW) dispersion forces to give key contributions to the dissociation energy. The question raised whether functionals that incorporate vdW forces implicitly into t...

  19. Modeling the Impact of Deformation on Unstable Miscible Displacements in Porous Media

    Science.gov (United States)

    Santillán, D.; Cueto-Felgueroso, L.

    2014-12-01

    Coupled flow and geomechanics is a critical research challenge in engineering and the geosciences. The simultaneous flow of two or more fluids with different densities or viscosities through deformable media is ubiquitous in environmental, industrial, and biological processes, including the removal of non-aqueous phase liquids from underground water bodies, the geological storage of CO2, and current challenges in energy technologies, such as enhanced geothermal systems, unconventional hydrocarbon resources or enhanced oil recovery techniques. Using numerical simulation, we study the interplay between viscous-driven flow instabilities (viscous fingering) and rock mechanics, and elucidate the structure of the displacement patterns as a function of viscosity contrast, injection rate and rock mechanical properties. Finally, we discuss the role of medium deformation on transport and mixing processes in porous media.

  20. Transient displacement induced in shear wave elastography: comparison between analytical results and ultrasound measurements.

    Science.gov (United States)

    Elkateb Hachemi, M; Callé, S; Remenieras, J P

    2006-12-22

    It is now accepted that an effective way to investigate the elastic properties of soft tissues is to generate a localized transient acoustic radiation force and to follow the associated displacements in the time/space domain. Shear waves induced by this stress field are particularly interesting in this kind of medium because they are governed by the shear elastic modulus mu, which is directly linked to the Young modulus, and spatial distribution and temporal evolution of the transient motion induced must therefore be obtained in detail. We report here a model based on the elastodynamic Green's function formalism to describe these displacements. 3D simulation of radiation force in homogenous elastic media was performed and the displacement curves computed at different radial distances for different temporal force profiles. Amplitude and duration of displacement were found to be reliable parameters to characterize the elastic properties of the medium. Experimental measurements were performed in a homogeneous agar-gelatin tissue-mimicking phantom, and two transducers were used to generate the radiation force and follow the induced displacements. Displacements obtained from different lateral locations around the applied force axis were then used to reconstruct the shear-wave propagation in a scan plane as a function of time. The experimental displacements/curves agreed with the theoretical profiles obtained by the elastodynamic Green's function formalism. PMID:16843510

  1. Aryl-derivatized, water-soluble functionalized carbon nanotubes for biomedical applications

    International Nuclear Information System (INIS)

    The functionalization of very-thin multi-walled carbon nanotubes (VT-MWNTs) with an aniline derivative, via the protocol of in situ generated aryl diazonium salts results, upon acidic deprotection of the terminal BOC group, on the formation of the water-soluble positively charged ammonium functionalized VT-MWNTs-NH3+ material. The new materials have been structurally and morphologically characterized by infra-red (ATR-IR) spectroscopy and transmission electron microscopy (TEM). The quantitative calculation of the grafted aryl units onto the skeleton of VT-MWNTs has been estimated by thermogravimetric analysis (TGA), while the quantitative Kaiser test showed the amine group loaded onto VT-MWNTs-NH3+ material. The aqueous solubility of this material has allowed the performance of some initial toxicological in vitro investigations

  2. Percolation line, response functions, and Voronoi polyhedra analysis in supercritical water

    Directory of Open Access Journals (Sweden)

    J. Škvor

    2012-06-01

    Full Text Available The problem of a physical relevance (meaning of percolation in supercritical fluids is addressed considering a primitive model of water. Two different criteria, physical and configurational, are used for the cluster definition in Monte Carlo simulations over a range of pressures to determine the percolation line and skewness, and a theoretical analytic equation of state is used to evaluate response functions. It is found that both criteria yield practically the same percolation line. However, unlike the findings for simple fluids, the loci of the response function extrema exhibit density/pressure dependence quite different from that of the percolation line. The only potential coincidence between the loci of the extrema of a thermodynamic property and a detectable structural change is found for the coefficient of isothermal compressibility and Voronoi neighbors distribution skewness maximum.

  3. Water level monitoring device in nuclear reactor

    International Nuclear Information System (INIS)

    Purpose: To monitor the water level in a pressure vessel of BWR type nuclear reactors at high accuracy by improving the compensation functions. Constitution: In the conventional water level monitor in a nuclear reactor, if the pressure vessel is displaced by the change of the pressure in the reactor or the temperature of the reactor water, the relative level of the reference water head in a condensation vessel is changed to cause deviation between the actual water level and the indicated water level to reduce the monitoring accuracy. According to the invention, means for detecting the position of the reference water head and means for detection the position in the condensation vessel are disposed to the pressure vessel. Then, relative positional change between the condensation vessel and the reference water head is calculated based on detection sinals from both of the means. The water level is compensated and calculated by water level calculation means based on the relative positional change, water level signals from the level gage and the pressure signals from the pressure gage. As a result, if the pressure vessel is displaced due to the change of the temperature or pressure, it is possible to measure the reactor water level accurately thereby remakably improve the reliability for the water level control in the nuclear reactor. (Horiuchi, T.)

  4. Plant Functional Type Shifts in Big Sagebrush Ecosystems: Impacts on Dryland Ecosystem Water Balance

    Science.gov (United States)

    Bradford, J. B.; Schlaepfer, D.; Lauenroth, W. K.

    2014-12-01

    Terrestrial vegetation influences hydrologic cycling. In water-limited, dryland ecosystems, altered ecohydrology as a consequence of vegetation change can impact vegetation structure, ecological functioning and ecosystem services. Shrub steppe ecosystems dominated by big sagebrush (Artemisia tridentata) are widespread across western North America but have been altered over the past century, and changes are likely to continue. The ecohydrological consequences of sagebrush removal and reestablishment remains unclear. To characterize the immediate and medium-term patterns of water cycling and availability following sagebrush plant community alteration, we applied the SOILWAT ecosystem water balance model to 898 sites across the distribution of sagebrush ecosystems, representing the three primary big sagebrush ecosystem types: sagebrush shrublands, sagebrush steppe and montane sagebrush. At each site we examined three vegetation conditions representing intact sagebrush, recently disturbed sagebrush and recovered but grass-dominated vegetation. Transition from shrub to grass dominance decreased precipitation interception and transpiration and increased soil evaporation and deep drainage. Relative to intact big sagebrush vegetation, simulated soils in the herbaceous vegetation phases typically had drier surface layers and wetter deep layers. Our simulations suggested that alterations in ecosystem water balance may be most pronounced in vegetation representing recently disturbed conditions (herbaceous vegetation with low biomass) and modest in conditions representing recovered, but still grass-dominated, vegetation. The ecohydrological impact of simulated big sagebrush removal depended on climate; while short-term changes in water balance were greatest in wet areas represented by the montane sagebrush ecosystem type, medium-term impacts were greatest in dry areas of sagebrush shrublands and sagebrush steppe.

  5. Water in biological membranes at interfaces: does it play a functional role?

    Scientific Electronic Library Online (English)

    E. A., Disalvo; F., Lairion; F., Martini; H., Almaleck; S., Diaz; G., Gordillo.

    2004-12-01

    Full Text Available El propósito de este trabajo es analizar la organización delaguaen la interfaz de una membrana biológica y su relevancia en las propiedades de superficie y en la adsorción de proteínas. El enfoque consiste en considerar que la función celular está confinada a un medio restringido en agua, el interio [...] r celular, en el cuaál la proximidad de la membrana puede ser clave para regular la actividad enzimática y la permeabilidad. Como la bicapa lipidica es la estructura básica de la membrana celular, los sitios de hidratación en la cabeza polar se analizan por medio de espectrometría infrarroja a transformada de Fourier. La contribución de la hidratación al potencial dipolar y la respuesta dinámica de monocapas de diferente composicioneslipídicas se investiganmediante determinación de potenciales de superficie yvoltametría cíclica. La modificación de esas propiedades a causa del reemplazo de agua por polioles como trehalosa y floretina y por la inserción de proteínas acuosolubles, ha sido también investigada. Abstract in english The purpose of this review is to examine and discuss the ways in which water is organized at the interface of a biological membrane. The relevance of this structure to the surface properties and to the adsorption of proteins in membranes is also analized. The approach is based on the idea that cell [...] functions are confined to a restricted water media, the cell interior, in which the proximity of the membrane may bekey to regulating the enzyme activity and the cell membrane permeability. As the lipid bilayer is the structural base ofcell membranes, the distribution of water in the surface sites of a phospholipid membrane is analyzed by means of Fourier Transform spectrometry. The polarization of water at the surface was looked into through the measure ofsurface potentials and the dynamics of the surface hydration by cyclic voltammetry. Modification of these properties by the replacement of water bypolyol molecules such as trehalose and phloretin and by the insertion of aqueous soluble enzymes, has also been investigated.

  6. Cardiorespiratory responses during deep water running with and without horizontal displacement at different cadences / Respostas cardiorrespiratórias durante a corrida em piscina funda com e sem deslocamento horizontal em diferentes ritmos / Respuestas cardiorrespiratorias de la carrera en aguas profundas con y sin desplazamiento horizontal y en diferentes cadencias

    Scientific Electronic Library Online (English)

    A.C., Kanitz; G.V., Liedtke; S.S., Pinto; C.L., Alberton; L.F.M., Kruel.

    2014-12-01

    Full Text Available Objetivo: comparar as respostas cardiorrespiratórias durante corrida em piscina funda profunda com e sem deslocamento horizontal em diferentes ritmos. Métodos: Doze mulheres jovens realizaram corrida aquática com e sem deslocamento durante quatro minutos, em três ritmos distintos: a) 60 bpm; b) 80 b [...] pm; e c) 100 bpm. A frequência cardíaca (FC), ventilação (VE) e o consumo de oxigênio (VO2) foram coletados no último minuto de cada teste. Two-way ANOVA para medidas repetidas foi utilizada com o teste post hoc Bonferroni's (p Abstract in spanish Objetivo: comparar las respuestas cardiorrespiratorias durante la carrera en aguas profundas con y sin desplazamiento horizontal y a diferentes cadencias. Método: Doce mujeres jóvenes realizaron la carrera en aguas profundas con y sin desplazamiento durante cuatro minutos a tres cadencias diferentes [...] : a) 60 bpm, b) 80 bpm, y c) 100 bpm. La frecuencia cardíaca (FC), la ventilación (VE) y el consumo de oxígeno (VO2) se recogieron en el último minuto de cada prueba. ANOVA de dos vías para medidas repetidas con post hoc de Bonferroni (p Abstract in english Objective: To compare the cardiorespiratory responses during deep water running with and without displacement at different cadences. Methods: Twelve young women performed deep water running with and without displacement during 4 min at three separate cadences: (a) 60 bpm; (b) 80 bpm; and (c) 100 bpm [...] . The heart rate (HR), ventilation (Ve) and oxygen uptake (VO2) were collected in the last minute of each test. Two-way ANOVA for repeated measures was used with Bonferroni's post hoc test (p

  7. Displacement chromatography of isomers and therapeutic compounds.

    Science.gov (United States)

    Qi, Yan; Huang, Junxiong

    2002-06-14

    Displacement chromatography was successfully used to separate a binary isomer mixture, epirubicin and doxorubicin, on Kromasil KR100-10 C18 250x4.6 mm I.D. (10 microm) column. Displacement parameters such as the types and the concentrations of displacer, the composition and the flow rate of the mobile phase were critically examined in this study. The displacer employed was 30 mg/ml benzethonium chloride. Loading of feed at lower initial organic level of mobile phase coupled with displacement at higher organic level was found to give efficient separation. A 30-mg amount of binary isomer mixture was separated on an analytical column. The purification of epirubicin from the closely related impurities present in raw product solution by displacement chromatography was also investigated. The purity of epirubicin required was greater than 99% with a recovery of 60%. The results have indicated that this process made good use of the high feed load, low solvent costs, and high resolution characteristics of displacement chromatography and offered the chromatographic engineer a powerful tool for the preparative purification of therapeutic compounds. PMID:12141564

  8. Application of systematic sequences of wave functions to the water dimer

    International Nuclear Information System (INIS)

    A systematic series of calculations encompassing a wide range of basis sets and correlated methods has been used to estimate the complete basis set, full CI hydrogen bond strength in the water dimer system. The largest basis set included up through h polarization functions on oxygen and g functions on hydrogen. The complete basis set limit for the self-consistent-field (SCF) interaction energy is estimated to be -3.55 kcal/mol with an accompanying correlation contribution of ?-1.5 kcal/mol. This leads to an interaction energy of -5.1 kcal/mol, exclusive of vibrational zero-point considerations, and is in good agreement with experimental measurements of -5.4±0.7 kcal/mol. Inclusion of an approximate adjustment for the basis set superposition error via the Boys/Bernardi counterpoise correction was found to substantially improve agreement with ?E?, our estimate of the complete basis set interaction energy, at the both the SCF and correlated levels for basis sets that were lacking in sufficient near-valence diffuse functions. For diffuse-function-augmented basis sets, application of the CP correction was found to sometimes worsen agreement with ?E?

  9. An old test for new neurons: refining the Morris water maze to study the functional relevance of adult hippocampal neurogenesis

    OpenAIRE

    Garthe, Alexander; Kempermann, Gerd

    2013-01-01

    The Morris water maze represents the de-facto standard for testing hippocampal function in laboratory rodents. In the field of adult hippocampal neurogenesis, however, using this paradigm to assess the functional relevance of the new neurons yielded surprisingly inconsistent results. While some authors found aspects of water maze performance to be linked to adult neurogenesis, others obtained different results or could not demonstrate any effect of manipulating adult neurogenesis. In this rev...

  10. An old test for new neurons: refining the Morris water maze to study the functional relevance of adult hippocampal neurogenesis

    OpenAIRE

    AlexanderGarthe

    2013-01-01

    The Morris water maze represents the de-facto standard for testing hippocampal function in laboratory rodents. In the field of adult hippocampal neurogenesis, however, using this paradigm to assess the functional relevance of the new neurons yielded surprisingly inconsistent results. While some authors found aspects of water maze performance to be linked to adult neurogenesis, others obtained different results or could not demonstrate any effect of manipulating adult neurogenesis. In this...

  11. Instability in Immiscible Fluids Displacement from Cracks and Porous Samples

    Science.gov (United States)

    Smirnov, N. N.; Nikitin, V. F.; Ivashnyov, O. E.

    2002-01-01

    problems of terrestrial engineering and technology. Surface tension affected flows in porous media could be much better understood in microgravity studies eliminating the masking effects of gravity. Saffman-Taylor instability of the interface could bring to formation and growth of "fingers" of gas penetrating the bulk fluid. The growth of fingers and their further coalescence could not be described by the linear analysis. Growth of fingers causes irregularity of the mixing zone. The tangential velocity difference on the interface separating fluids of different densities and viscousities could bring to a Kelvin-Helmholtz instability resulting in "diffusion of fingers" partial regularization of the displacement mixing zone. Thus combination of the two effects would govern the flow in the displacement process. fracture under a pressure differential displacing the high viscosity residual fracturing fluid. There are inherent instability and scalability problems associated with viscous fingering that play a key role in the cleanup procedure. Entrapment of residual fracturing fluid by the gas flow lowers down the quality of a fracture treatment leaving most of fluid in the hydraulic fracture thus decreasing the production rate. The gravity effects could play essential role in vertical hydraulic fractures as the problem is scale dependent. displacement of viscous fluid by a less viscous one in a two-dimensional channel with vertical breaks, and to determine characteristic size of entrapment zones. Extensive direct numerical simulations allow to investigate the sensitivity of the displacement process to variation of values of the main governing parameters. were found for the two limiting cases: infinitely wide cell, and narrow cell with an infinitely small gap between the finger and the side walls. governing parameters. The obtained solutions allowed to explain the physical meaning of the exiting empirical criteria for the beginning of viscous fingering and the growth of a number of fingers in the cell, and allowed us to make some additional suggestions for the cleanup procedure. depending on the resident fluid properties, for which the displacement still remains stable. viscous one were carried out. Validation of the code was performed by comparing the results of model problems simulations with the existing solutions published in literature. Being in a good agreement with the previously obtained results, nevertheless, the developed code is an advanced one. While the existing codes could operate with linear equations and regular geometry and initial disturbances only, the new code permits taking into account non-linear effects as well. characterizing the quality of displacement. The functional dependence of the dimensionless criteria on the values of governing parameters needs further investigations. Services, an international company in the oil and gas industry.

  12. Comparison of Geophysical Model Functions for SAR Wind Speed Retrieval in Japanese Coastal Waters

    DEFF Research Database (Denmark)

    Takeyama, Yuko; Ohsawa, Teruo

    2013-01-01

    This work discusses the accuracies of geophysical model functions (GMFs) for retrieval of sea surface wind speed from satellite-borne Synthetic Aperture Radar (SAR) images in Japanese coastal waters characterized by short fetches and variable atmospheric stability conditions. In situ observations from two validation sites, Hiratsuka and Shirahama, are used for comparison of the retrieved sea surface wind speeds using CMOD (C-band model)4, CMOD_IFR2, CMOD5 and CMOD5.N. Of all the geophysical model functions (GMFs), the latest C-band GMF, CMOD5.N, has the smallest bias and root mean square error at both sites. All of the GMFs exhibit a negative bias in the retrieved wind speed. In order to understand the reason for this bias, all SAR-retrieved wind speeds are separated into two categories: onshore wind (blowing from sea to land) and offshore wind (blowing from land to sea). Only offshore winds were found to exhibit the large negative bias, and short fetches from the coastline may be a possible reason for this. Moreover, it is clarified that in both the unstable and stable conditions, CMOD5.N has atmospheric stability effectiveness, and can keep the same accuracy with CMOD5 in the neutral condition. In short, at the moment, CMOD5.N is thought to be the most promising GMF for the SAR wind speed retrieval with the atmospheric stability correction in Japanese coastal waters, although there is ample room for future improvement for the effect from short fetch.

  13. Dielectric constant and density of water as a function of pressure at constant temperature

    Scientific Electronic Library Online (English)

    Wely Brasil, Floriano; Marco Antonio Chaer, Nascimento.

    2004-03-01

    Full Text Available In order to simulate the effects of hydrostatic pressure on protein folding/unfolding it is necessary to accurately describe the behavior of the dielectric constant and the density of the solvent (water), in the range of pressures (between 0.1 MPa and 2.0 GPa) and temperatures (below 75 ° C) require [...] d for pressure-induced unfolding. A simple equation of the form X = X (T, Pi) + a0 ln (a i+ P)/(a i + Pi) [were X is the property, Pi (in MPa) is the reference pressure and a i are coefficients adjusted to fit experimental values] is proposed to describe both properties as function of pressure, at constant temperatures. The equation reproduces available data for dielectric constant and density of water to an accuracy of 0.1%. Because of its simplicity and accuracy, the proposed equation is useful for simulation studies and for any other problem where the knowledge of those properties as a function of pressure is needed.

  14. Effect of hypoxaemia on water and sodium homeostatic hormones and renal function

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal

    1995-01-01

    Changes in body fluid homeostasis during acute hypoxaemia suggest a crucial role of renal function in acclimatization processes. Hypoxaemia stimulates sympathetic nervous activity, and also the cardiovascular system is affected with increases in heart rate and cardiac output. In most subjects, a hypoxic ventilatory response produces hypocapnia and respiratory alkalosis. Acute hypoxaemia depresses aldosterone secretion secondary to a direct effect on adrenal cells. Also plasma renin is decreased in resting hypoxaemic conditions, but the mechanism remains unknown. These hormonal changes may have the advantage of opposing excessive sodium and water retention, which characterizes acute mountain sickness. Short-term isocapnic or hypocapnic hypoxaemia in spontaneously breathing humans causes moderate if any increases in renal blood flow and only minor changes in GFR. In contrast, renal blood flow and GFR decreases during hypercapnic hypoxaemia. Renal clearance studies in humans after 24-48 hours in altitude hypoxia (4,350 m) demonstrate that glomerular and tubular function is only slightly changed in spite of marked depression of the renin-aldosterone system and increased plasma levels of norepinephrine. However, renal vascular tone may increase most probably secondary to the increased adrenosympathetic activity. In the first hours, acute hypoxaemia may induce an increased excretion of sodium and water. Previous studies suggest that the natriuretic response is caused by decreased reabsorption of sodium and bicarbonate in the proximal tubules secondary to the associated hyperventilation and hypocapnia. After 6 hours, sodium and water excretion is normalized or even depressed, dependent on the severity of acute mountain sickness. In view of the prompt increase in sodium and water excretion found during short-term hypoxaemia, the absence of such a response to more prolonged hypoxaemia suggests an adaptive time-dependent course of renal functional changes in hypoxaemia. Taken together, previous studies suggest that effects of acute hypoxaemia on renal haemodynamics are minor compared with effects on cerebral and coronary circulation. This might be the result of an appropriate resetting of autoregulatory mechanisms that would maintain the role of the kidney as a major sense organ to hypoxaemia and, subsequently, as a mediator of plasma volume regulation and erythropoietin synthesis.

  15. Thermodynamic properties of water sorption of jackfruit (Artocarpus heterophyllus Lam. as a function of moisture content

    Directory of Open Access Journals (Sweden)

    Ana Paula Prette

    2013-03-01

    Full Text Available The Jackfruit tree is one of the most significant trees in tropical home gardens and perhaps the most widespread and useful tree in the important genus Artocarpus. The fruit is susceptible to mechanical and biological damage in the mature state, and some people find the aroma of the fruit objectionable, particularly in confined spaces. The dehydration process could be an alternative for the exploitation of this product, and the relationship between moisture content and water activity provides useful information for its processing and storage. The aim of this study was to determine the thermodynamic properties of the water sorption of jackfruit (Artocarpus heterophyllus Lam. as a function of moisture content. Desorption isotherms of the different parts of the jackfruit (pulp, peduncle, mesocarp, peel, and seed were determined at four different temperatures (313.15, 323.15, 333.15, and 343.15 K in a water activity range of 0.02-0.753 using the static gravimetric method. Theoretical and empirical models were used to model the desorption isotherms. An analytical solution of the Clausius-Clapeyron equation was proposed to calculate the isosteric heat of sorption, the differential entropy, and Gibbs' free energy using the Guggenhein-Anderson-de Boer and Oswin models considering the effect of temperature on the hygroscopic equilibrium.

  16. Dynamics of supercooled water in nanotubes: Cage correlation function and diffusion coefficient

    Science.gov (United States)

    Khademi, Mahdi; Kalia, Rajiv K.; Sahimi, Muhammad

    2015-09-01

    Dynamics of low-temperature water in nanostructured materials is important to a variety of phenomena, ranging from transport in cement and asphaltene, to conformational dynamics of proteins in "crowded" cellular environments, survival of microorganisms at very low temperatures, and diffusion in nanogeoscience. Using silicon-carbide nanotubes as a prototype of nanostructured materials, extensive molecular dynamics simulations were carried out to study the cage correlation function C (t ) and self-diffusivity D of supercooled water in the nanotubes. C (t ) , which measures changes in the atomic surroundings inside the nanotube, follows the Kohlrausch-Williams-Watts law, C (t ) ˜exp[-(t/? ) ?] , where ? is a relaxation time and ? is a topological exponent. For the temperature range 220 Kwater does not freeze in the nanotube over the studied temperature range, and that the Stokes-Einstein relation breaks down.

  17. Characteristic of Water Pervaporation Using Hydrophilic Composite Membrane Containing Functional Nano Sized NaA zeolites

    International Nuclear Information System (INIS)

    The NaA zeolite particles were dispersed in a poly(vinyl alcohol) (PVA) matrix to prepare a composite membrane. The nano sized zeolite particles of NaA were synthesized in the laboratory and the mean size was approximately 60 nm. Pervaporation characteristics such as a permeation flux and a separation factor were investigated using the membrane as a function of the feed concentration from 0.01 to 0.05 mole fraction and the weight % of NaA particles between 0 wt% and 5 wt% in the membrane. Also, the micro sized particles of 5 mm were dispersed in the membrane for a comparison purpose. When the ethanol concentration in the feed solution was 0.01 mole fraction, the flux of water significantly increased from 600 g/m2/hr to 2000 g/m2/hr as the content of the nano NaA particles in the membrane increased from 0 wt% to 5 wt%, while the NaA particles improved the separation factor from 1.5 to 7.9. When the flux of water through the membrane containing nano sized particles was roughly 15% increased compared to the micro sized particles, whereas the separation factor of water was found to be approximately 5% increased. It can be said that the role of the nano sized NaA particles is quite important since both the flux and the separation factor are strongly affected

  18. Enhancing the Multivariate Signal of 15O water PET Studies With a New Non-Linear Neuroanatomical Registration Algorithm

    DEFF Research Database (Denmark)

    Kjems, Ulrik; Storther, Stephen C.; Anderson, Jon; Law, Ian; Hansen, Lars Kai

    1999-01-01

    This paper addresses the problem of neuro-anatomical registration across individuals for functional [15O]water PET activation studies. A new algorithm for 3D non-linear structural registration (warping) of MR scans is presented. The method performs a hierarchically scaled search for a displacement field maximizing one of several voxel similarity measures derived from the two dimensional histogram of matched image intensities, subject to a regularizer that ensures smoothness of the displacement f...

  19. Enhanced Oil Recovery Using Micron-Size Polyacrylamide Elastic Microspheres (MPEMs): Underlying Mechanisms and Displacement Experiments

    KAUST Repository

    Yao, Chuanjin

    2015-10-12

    Micron-size polyacrylamide elastic microsphere (MPEM) is a newly developed profile control and oil displacement agent for enhanced oil recovery in heterogeneous reservoirs. In this study, laboratory experiments were performed to characterize the viscoelastic properties of MPEMs in brine water. A transparent sandpack micromodel was used to observe the microscopic flow and displacement mechanisms, and parallel-sandpack models were used to investigate the profile control and oil displacement performance using MPEMs in heterogeneous reservoirs. The results indicate that MPEMs almost do not increase the viscosity of injection water and can be conveniently injected using the original water injection pipelines. The microscopic profile control and oil displacement mechanisms of MPEMs in porous media mainly behave as selective-plugging in large pores, fluid diversion after MPEMs plugging, oil drainage caused by MPEMs breakthrough, and the mechanism of oil droplets converging into oil flow. MPEMs have a high plugging strength, which can tolerate a long-term water flushing. MPEMs can selectively enter and plug the large pores and pore-throats in high permeability sandpack, but almost do not damage the low permeability sandpack. MPEMs can effectively divert the water flow from the high permeability sandpack to the low permeability sandpack and improve the sweep efficiency of low permeability sandpack and low permeability area in the high permeability sandpack. The results also confirm the dynamic process of profile control and oil displacement using MPEMs in heterogeneous reservoirs.

  20. Determining the impacts of trawling on benthic function in European waters : a biological traits approach

    DEFF Research Database (Denmark)

    Bolam, Stefan; Kenny, Andrew

    One of the most widespread yet manageable pressures we impose on the seabed is disturbance of the substrate by towed demersal fishing gear (bottom trawling and dredging). Over the past forty to fifty years, many studies have been conducted specifically aiming to understand the impacts of such fishing gear on the seabed communities. Their outcomes have demonstrated dramatic effects of bottom trawling on the structure of marine ecosystems although impacts tend to be wide-ranging, depending upon the gear, intensity, spatial area and the nature of the seabed habitats. However, understanding the functional impacts of this activity (as opposed to impacts on the structure of benthic assemblages) has only recently been attempted. Advances in the application of biological traits analysis (BTA) wherein the assemblages are described in terms of their life history, behavioural and morphological characteristics, have allowed us to better understand the interactions between the benthic fauna and their environment at a functional level. We present the initial findings of work conducted under the auspices of the EU-funded project ‘BENTHIS’ which aims to improve our understanding of the impacts of trawling on benthic ecosystem functioning over much larger spatial scales than previously undertaken. Biological traits information from 887 stations across European waters (Norwegian, UK, Belgian, Dutch, Danish waters, the Mediterranean and Black Sea) were analysed to: i) quantify the relationships between infaunal trait composition and environmental variables (depth, sediment granulometry); ii) determine the relationship between traits and habitat type (EUNIS level 4); and iii) assess the relationships between trawling pressure (using data derived under BENTHIS; see Eigaard et al., this volume) and traits composition

  1. Myocardial strains from 3D displacement encoded magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Kindberg Katarina

    2012-04-01

    Full Text Available Abstract Background The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE, make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. Methods We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. Results The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Conclusions Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.

  2. Myocardial strains from 3D displacement encoded magnetic resonance imaging

    International Nuclear Information System (INIS)

    The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts

  3. Assisting the return of displaced Dinka Bor

    Directory of Open Access Journals (Sweden)

    Paul Murphy

    2005-11-01

    Full Text Available The issues involved in supporting the return of internally displaced Dinka Bor communities highlight the complex, and often ignored, challenges of addressing the consequencesof South-South conflict.

  4. Epitaxial growth by monolayer restricted galvanic displacement

    Directory of Open Access Journals (Sweden)

    Vasili? Rastko

    2012-01-01

    Full Text Available The development of a new method for epitaxial growth of metals in solution by galvanic displacement of layers pre-deposited by underpotential deposition (UPD was discussed and experimentally illustrated throughout the lecture. Cyclic voltammetry (CV and scanning tunneling microscopy (STM are employed to carry out and monitor a “quasi-perfect”, two-dimensional growth of Ag on Au(111, Cu on Ag(111, and Cu on Au(111 by repetitive galvanic displacement of underpotentially deposited monolayers. A comparative study emphasizes the displacement stoichiometry as an efficient tool for thickness control during the deposition process and as a key parameter that affects the deposit morphology. The excellent quality of layers deposited by monolayer-restricted galvanic displacement is manifested by a steady UPD voltammetry and ascertained by a flat and uniform surface morphology maintained during the entire growth process.

  5. PDT - PARTICLE DISPLACEMENT TRACKING SOFTWARE

    Science.gov (United States)

    Wernet, M. P.

    1994-01-01

    Particle Imaging Velocimetry (PIV) is a quantitative velocity measurement technique for measuring instantaneous planar cross sections of a flow field. The technique offers very high precision (1%) directionally resolved velocity vector estimates, but its use has been limited by high equipment costs and complexity of operation. Particle Displacement Tracking (PDT) is an all-electronic PIV data acquisition and reduction procedure which is simple, fast, and easily implemented. The procedure uses a low power, continuous wave laser and a Charged Coupled Device (CCD) camera to electronically record the particle images. A frame grabber board in a PC is used for data acquisition and reduction processing. PDT eliminates the need for photographic processing, system costs are moderately low, and reduced data are available within seconds of acquisition. The technique results in velocity estimate accuracies on the order of 5%. The software is fully menu-driven from the acquisition to the reduction and analysis of the data. Options are available to acquire a single image or 5- or 25-field series of images separated in time by multiples of 1/60 second. The user may process each image, specifying its boundaries to remove unwanted glare from the periphery and adjusting its background level to clearly resolve the particle images. Data reduction routines determine the particle image centroids and create time history files. PDT then identifies the velocity vectors which describe the particle movement in the flow field. Graphical data analysis routines are included which allow the user to graph the time history files and display the velocity vector maps, interpolated velocity vector grids, iso-velocity vector contours, and flow streamlines. The PDT data processing software is written in FORTRAN 77 and the data acquisition routine is written in C-Language for 80386-based IBM PC compatibles running MS-DOS v3.0 or higher. Machine requirements include 4 MB RAM (3 MB Extended), a single or multiple frequency RGB monitor (EGA or better), a math co-processor, and a pointing device. The printers supported by the graphical analysis routines are the HP Laserjet+, Series II, and Series III with at least 1.5 MB memory. The data acquisition routines require the EPIX 4-MEG video board and optional 12.5MHz oscillator, and associated EPIX software. Data can be acquired from any CCD or RS-170 compatible video camera with pixel resolution of 600hX400v or better. PDT is distributed on one 5.25 inch 360K MS-DOS format diskette. Due to the use of required proprietary software, executable code is not provided on the distribution media. Compiling the source code requires the Microsoft C v5.1 compiler, Microsoft QuickC v2.0, the Microsoft Mouse Library, EPIX Image Processing Libraries, the Microway NDP-Fortran-386 v2.1 compiler, and the Media Cybernetics HALO Professional Graphics Kernal System. Due to the complexities of the machine requirements, COSMIC strongly recommends the purchase and review of the documentation prior to the purchase of the program. The source code, and sample input and output files are provided in PKZIP format; the PKUNZIP utility is included. PDT was developed in 1990. All trade names used are the property of their respective corporate owners.

  6. 48 CFR 952.226-74 - Displaced employee hiring preference.

    Science.gov (United States)

    2010-10-01

    ... false Displaced employee hiring preference. 952.226-74 Section 952.226-74...226-74 Displaced employee hiring preference. As prescribed in 48 CFR (DEAR...clause. Displaced Employee Hiring Preference (JUN 1997) (a) Definition....

  7. Light-induced effects on Brownian displacements

    OpenAIRE

    Bhalerao, Anish S.; Pollack, Gerald H

    2010-01-01

    Earlier work on particles in aqueous solution indicated that particle hydration could be expanded by incident light. To assess the effects of expanded hydration we measured Brownian displacements of microspheres exposed to light of varying intensities and wavelengths. Displacements were consistently diminished in an intensity-dependent and wavelength-dependent fashion, and center-to-center distances between microspheres were shifted to higher values. We conclude that suspended microspheres ar...

  8. Static displacements and chemical correlations in alloys

    OpenAIRE

    Chakraborty, Bulbul

    1995-01-01

    Recent experiments in metallic solid solutions have revealed interesting correlations between static pair-displacements and the ordering behavior of these alloys. This paper discusses a simple theoretical model which successfully explains these observations and which provides a natural framework for analyzing experimental measurements of pair-displacements and chemical correlations in solid solutions. The utility and scope of this model is demonstrated by analyzing results o...

  9. High Precision Displacement Measurement Using Fiber Optics

    CERN Document Server

    Berkovic, G; Scandale, Walter; Shafir, E; Todesco, Ezio

    2002-01-01

    We describe laboratory experiments with a fiber-optic sensor employing a chirped laser that detects, with 20-30 micrometer accuracy, displacements of a remote reflective target at distance of 200-500 mm. The requirements of chirp linearity and laser coherence in order to achieve this sensitivity are elaborated. This sensor can be employed for remotely sensing minute displacements of objects in harsh environments, including cryo-magnets in particle accelerators.

  10. The intergenerational effects of worker displacement

    OpenAIRE

    Page, Marianne; Stevens, Ann Huff; Oreopoulos, Philip

    2005-01-01

    This paper uses variation induced by firm closures to explore the intergenerational effects of worker displacement. Using a Canadian panel of administrative data that follows almost 60,000 father-child pairs from 1978 to 1999 and includes detailed information about the firms at which the father worked, we construct narrow treatment and control groups whose fathers had the same level of permanent income prior to 1982 when some of the fathers were displaced. We demonstrate that job loss leads t...

  11. Symmetry breaking oxygen displacements in superconducting oxides

    International Nuclear Information System (INIS)

    This paper discusses atomic pair distribution analysis of pulsed neutron scattering data for superconducting oxides which indicates that some of the atoms, notably oxygen atoms, are displaced from the crystallographic high-symmetry sites, breaking the local symmetry. Anomalous displacements are seen in Tl-Ba-Ca-Cu-O in the vicinity of the superconducting transition temperature, suggesting an unusual nature of the superconducting state of this compound

  12. Analysis of monitored displacements in Golovec tunnel

    OpenAIRE

    Šlibar, Miha

    2005-01-01

    Modern tunnel construction includes everyday monitoring of 3-D displacements of primary lining using sophisticated geodetic instruments. Therefore, a large number of data is collected, which has to be interpreted correctly. Only in such a way the monitoring results can be useful during tunnel excavation. Correctly analysed displacements enable the prediction of tunnel behaviour up to two tunnel diameters ahead of current face position. Designers use this information to adjust the support syst...

  13. Atomic displacements due to interstitial hydrogen in Cu and Pd

    Indian Academy of Sciences (India)

    Hitesh Sharma; S Prakash

    2007-08-01

    The density functional theory (DFT) is used to study the atomic interactions in transition metal-based interstitial alloys. The strain field is calculated in the discrete lattice model using Kanzaki method. The total energy and hence atomic forces between interstitial hydrogen and transition metal hosts are calculated using DFT. The norm-conserving pseudopotentials for H, Cu and Pd are generated self-consistently. The dynamical matrices are evaluated considering interaction up to first nearest neighbors whereas impurity-induced forces are calculated with M32H shell (where M = Cu and Pd). The atomic displacements produced by interstitial hydrogen at the octahedral site in Cu and Pd show displacements of $7.36$% and $4.3$% of the first nearest neighbors respectively. Both Cu and Pd lattices show lattice expansion due to the presence of hydrogen and the obtained average lattice expansion $\\Delta V /V = 0.177$ for Cu and 0.145 for Pd.

  14. Factors shaping bacterial phylogenetic and functional diversity in coastal waters of the NW Mediterranean Sea

    Science.gov (United States)

    Boras, Julia A.; Vaqué, Dolors; Maynou, Francesc; Sà, Elisabet L.; Weinbauer, Markus G.; Sala, Maria Montserrat

    2015-03-01

    To evaluate the main factors shaping bacterioplankton phylogenetic and functional diversity in marine coastal waters, we carried out a two-year study based on a monthly sampling in Blanes Bay (NW Mediterranean). We expected the key factors driving bacterial diversity to be (1) temperature and nutrient concentration, together with chlorophyll a concentration as an indicator of phytoplankton biomass and, hence, a carbon source for bacteria (here called bottom-up factors), and (2) top-down pressure (virus- and protist-mediated mortality of bacteria). Phylogenetic diversity was analyzed by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA. Functional diversity was assessed by using monomeric carbon sources in Biolog EcoPlates and by determining the activity of six extracellular enzymes. Our results indicate that the bacterial phylogenetic and functional diversity in this coastal system is shaped mainly by bottom-up factors. A dendrogram analysis of the DGGE banding patterns revealed three main sample clusters. Two clusters differed significantly in temperature, nitrate and chlorophyll a concentration, and the third was characterized by the highest losses of bacterial production due to viral lysis detected over the whole study period. Protistan grazing had no effect on bacterial functional diversity, since there were no correlations between protist-mediated mortality (PMM) and extracellular enzyme activities, and utilization of only two out of the 31 carbon sources (N-acetyl-D-glucosamine and ?-cyclodextrin) was correlated with PMM. In contrast, virus-mediated mortality correlated with changes in the percentage of use of four carbon sources, and also with specific leu-aminopeptidase and ?-glucosidase activity. This suggests that viral lysate provides a pool of labile carbon sources, presumably including amino acids and glucose, which may inhibit proteolytic and glucosidic activity. Our results indicate that bottom-up factors play a more important role than top-down factors (i.e. viral lysis and protistan grazing) in shaping bacterial community structure and activity. Furthermore, they suggest that viruses play a more important role than protists in modifying community structure and functional diversity of bacteria in oligotrophic marine coastal waters.

  15. Gastric emptying of water in children with severe functional fecal retention

    Directory of Open Access Journals (Sweden)

    V.P.I. Fernandes

    Full Text Available The objective of this study was to evaluate gastric emptying (GE in pediatric patients with functional constipation. GE delay has been reported in adults with functional constipation. Gastric emptying studies were performed in 22 children with chronic constipation, fecal retention and fecal incontinence, while presenting fecal retention and after resuming regular bowel movements. Patients (18 boys, median age: 10 years; range: 7.2 to 12.7 years were evaluated in a tertiary pediatric gastroenterology clinic. Gastric half-emptying time of water (reference range: 12 ± 3?min was measured using a radionuclide technique immediately after first patient evaluation, when they presented fecal impaction (GE1, and when they achieved regular bowel movements (GE2, 12 ± 5 weeks after GE1. At study admission, 21 patients had reported dyspeptic symptoms, which were completely relieved after resuming regular bowel movements. Medians (and interquartile ranges for GE1 and GE2 were not significantly different [27.0 (16 and 27.5 (21 min, respectively (P = 0.10]. Delayed GE seems to be a common feature among children with chronic constipation and fecal retention. Resuming satisfactory bowel function and improvement in dyspeptic symptoms did not result in normalization of GE data.

  16. Gastric emptying of water in children with severe functional fecal retention

    Scientific Electronic Library Online (English)

    V.P.I., Fernandes; M.C.L., Lima; E.E., Camargo; E.F., Collares; J.M., Bustorff-Silva; E.A., Lomazi.

    2013-03-15

    Full Text Available The objective of this study was to evaluate gastric emptying (GE) in pediatric patients with functional constipation. GE delay has been reported in adults with functional constipation. Gastric emptying studies were performed in 22 children with chronic constipation, fecal retention an [...] d fecal incontinence, while presenting fecal retention and after resuming regular bowel movements. Patients (18 boys, median age: 10 years; range: 7.2 to 12.7 years) were evaluated in a tertiary pediatric gastroenterology clinic. Gastric half-emptying time of water (reference range: 12 ± 3?min) was measured using a radionuclide technique immediately after first patient evaluation, when they presented fecal impaction (GE1), and when they achieved regular bowel movements (GE2), 12 ± 5 weeks after GE1. At study admission, 21 patients had reported dyspeptic symptoms, which were completely relieved after resuming regular bowel movements. Medians (and interquartile ranges) for GE1 and GE2 were not significantly different [27.0 (16) and 27.5 (21) min, respectively (P = 0.10)]. Delayed GE seems to be a common feature among children with chronic constipation and fecal retention. Resuming satisfactory bowel function and improvement in dyspeptic symptoms did not result in normalization of GE data.

  17. Displacement sensor for indoor machine calibrations.

    Science.gov (United States)

    Mudassar, Asloob Ahmad; Butt, Saira

    2013-05-20

    This paper presents a simple displacement sensor for indoor machine calibrations. The sensor, which is placed in the path of a diverging laser beam, consists of two plane mirror pieces laterally displaced with the line joining their centers initially held perpendicular to the optical axis of the beam during the displacement of the sensor with one of the mirrors always traveling along the optical axis of the laser beam. The optical signals from the two mirrors are combined and a simple detector at the interference plane counts the fringes during the sensor displacement. The sensor could be mounted on the moving head of any mechanical machine, e.g., the lathe machine for displacement calibration. The device has been tested over a range of 10 cm beyond a distance of 150 cm from a diverging laser source giving an accuracy of 1.1015 ?m. Theoretical modeling, simulation, and experimental results are presented which establish that the proposed sensor can be used as a promising displacement measuring device. PMID:23736230

  18. In situ variations and relationships of water quality index with periphyton function and diversity metrics in Baiyangdian Lake of China.

    Science.gov (United States)

    Yan, Jinxia; Liu, Jingling; Ma, Muyuan

    2014-05-01

    The variations and associations of abiotic and biotic variables in Baiyangdian Lake, China, were analyzed in situ. Abiotic variables included eleven water quality parameters, and were characterized by water quality index (WQI). Biotic variables included periphyton function and diversity metrics. WQI differed in different seasons at sampling sites and the highest value of WQI was observed in October 2009. Periphyton function metrics, expressed by extracellular enzyme activities of alkaline phosphatase, ?-glucosidase and leucine aminopeptidase, gross primary productivity and daily respiration rate, and diversity indices, in terms of Shannon diversity index and Berger-Parker abundance index, showed significantly temporal and spatial variations. Regression linear analysis illustrated a fairly good correlation of WQI with periphyton function and diversity indices, Shannon diversity index was the best correlated with WQI (r = 0.904, P index (r = -0.840, P water quality, and give us messages for monitoring water quality accurately. PMID:24557602

  19. Complications in Receiver Function Analysis on the Ocean Floor: Water and Sediment Reverberations

    Science.gov (United States)

    Harmon, N.; Forsyth, D. W.; Webb, S. C.

    2005-12-01

    Receiver function analysis of ocean bottom seismometer (OBS) data provides a unique opportunity for high resolution imaging of subsurface seismic discontinuities. However, because the OBS is located at the fluid solid boundary of the seafloor, reverberations from both the water column above and the oceanic crust below complicate the deconvolved signal. In addition, ultra slow sediment layers ( .5) converted phases from the crust-sediment boundary, reverberate in the sediment column. Using the 11 month OBS deployment of the Gravity Lineations Intraplate Melting Petrology and Seismologic Expedition (GLIMPSE) we observe both the water column reverberations on the pressure record of the instruments as well as the sediment layer reverberations on the radial component from teleseismic events. We use this data to parameterize both types of reverberations to enhance the interpretation of receiver functions. Synthetic seismograms indicate that the amplitudes of water reverberations dominate the pressure record with a more subtle effect on the vertical record. Using reflection coefficient and the two way travel times determined from the observed pressure records we deconvolved the reverberation signal from the pressure and vertical component of our data, reducing the amplitudes of the water column reverberations in both records for up to 25 s before the effects of focusing and defocusing of the reverberation signal by heterogeneities render the assumption of simple reflections on a flat plane invalid. Similar analysis of synthetic seismograms indicates that sediment reverberations dominate the high frequency spectra of the radial component. We determined the S-P amplitude and delay time for the P-S conversion from the crust-sediment boundary from a suite of events at different slownesses. As expected the delay times are constant and on the order of a few tenths of a second because of the near vertical incidence caused by the sudden drop in shear velocity, and the S-P amplitudes increase with increasing slowness. With these two parameters we are able to invert for sediment layer thickness and shear velocity, and perhaps more importantly provide a minimum station correction for S delay times for use in body wave tomography.

  20. Thermal regulation of functional groups in running water ecosystems. Progress report, October 1, 1975--June 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Cummins, K.W.; Klug, M.J.

    1976-07-01

    Progress is reported on the following research projects: characterization of functional groups of running water organisms, particularly macroconsumers; studies on relationship of functional groups to qualitative and quantitative characteristics of organic inputs to stream ecosystems; studies on relationship of functional groups to thermal regimes; and dimensioning the control of feeding and growth by temperature and food quality and quantity and determining the extent of compensatory action of each. (HLW)

  1. Modified Newmark method involving excess pore pressure to express unlimited landslide displacement

    Science.gov (United States)

    Fukuoka, H.; Tsukui, A.

    2012-12-01

    Newmark method is the most popular approach to assess the displacement of landslides induced by earthquakes using seismic acceleration, slope inclination, and friction parameters. However, this method always shows limited shear displacement no matter how the acceleration is large and duration is long. This is partly because it does not include any pore pressure, especially excess pore water pressure generated under long shear displacement. As shown by series of earthquake wave-form loading undrained ring shear tests by Disaster Prevention Research Institute of Kyoto University, grain crushing or soil skelton collapse can contribute to generation of high excess pore pressure and let the soil to reach liquefaction state ("Sliding surface liquefaction"). Many of unlimited landslide displacement have been revealed that this phenomena must be the key mechanism. In the test series of mixture of silica sands and dry-ice pellets (frozen carbon-dioxide), for studying the mechanism of the gasification of methane hydrates in the submarine landslides which likely to trigger large scale submarine landslides, authors have found linear relationship between log of excess pore pressure ratio (generated pore pressure / initial effective normal stress) and log of shear displacement. By embedding this relation into the Newmark method, unlimited shear displacement can appear under certain slope inclination and exaggerated acceleration. Authors show there is critical slope inclination for unlimited displacement when given acceleration waveform.

  2. Reconstruction of myocardial tissue motion and strain fields from displacement-encoded MR imaging

    OpenAIRE

    LIU Yi; Wen, Han; Gorman, Robert C; Pilla, James J.; Gorman, Joseph H; Buckberg, Gerald; Teague, Shawn D; Kassab, Ghassan S.

    2009-01-01

    A quantitative analysis of myocardial mechanics is fundamental to understanding cardiac function, diagnosis of heart disease, and assessment of therapeutic intervention. Displacement encoding with stimulated-echo (DENSE) magnetic resonance imaging (MRI) technique was developed to track the three-dimensional (3D) displacement vector of discrete material grid points in the myocardial tissue. Despite the wealth of information gained from DENSE images, the current software only provides two-dimen...

  3. Temperature-modulated water filtration using microgel-functionalized hollow-fiber membranes.

    Science.gov (United States)

    Menne, Daniel; Pitsch, Fee; Wong, John E; Pich, Andrij; Wessling, Matthias

    2014-05-26

    In the present work, we investigate the potential of aqueous polymer microgels in membrane technology, especially for filtration applications. The poly(N-vinylcaprolactam)-based microgels exhibit thermoresponsive behavior and were employed to coat hollow-fiber membranes used for micro- and ultrafiltration. We discuss the preparation of microgel-modified membranes (by "inside-out" as well as "outside-in" filtration in dead-end mode). The clean-water permeability and stability of these membranes was studied not only as a function of time, but also of temperature. The microgel-modified membranes exhibit a reversible thermoresponsive behavior whereby both the resistance and the retention increased with decreasing temperature. PMID:24740583

  4. Hazard-function modeling of early effects mortality risks associated with light water nuclear reactor accidents

    International Nuclear Information System (INIS)

    A hazard-function modeling technique is used to derive risk estimators for mortality from specific early and continuing effects of exposure to radiations that could result from an accident at a light water nuclear power plant. The risk estimators allow for the accommodation of dose rate effects. Two modes of exposure are considered: (1) brief external exposure, mainly to cloud-shine and ground-shine gamma rays and (2) protracted internal exposure, mainly to beta radiation from inhaled and ingested radionuclides. Critical organs considered are the bone marrow, gastrointestinal tract, and lungs. The procedure used to develop the risk estimators is generic and, with additional parameters, could accommodate other types fo accidents, including those associated with plutonium or thorium fuel cycles. 16 references, 5 figures, 2 tables

  5. Effect of heavy water on structure-function relationship of lactate dehydrogenase from Lactobacillus casei

    International Nuclear Information System (INIS)

    Structural and functional behaviour of lactate dehydrogenase purified from Lactobacillus casei was compared in H2O and heavy water (D2O). The enzyme showed reduced activity in D2O, being only 45% of that observed in H2O. The modulations of the enzyme caused by the substrate and fructose 1,6-diphosphate examined at varying pH and pD values indicated decreased cooperativity in D2O. The elution profiles of the enzyme on Sephadex G-200 in the presence of the substrate and fructose 1, 6-diphosphate at varying pD values showed a shift towards lower molecular weight species. At pD 5,4 fructose diphosphate did not cause any further shift in the elution pattern which was otherwise observed in H2O. (author)

  6. Water Extract of Acer tegmentosum Reduces Bone Destruction by Inhibiting Osteoclast Differentiation and Function

    Directory of Open Access Journals (Sweden)

    Hyunil Ha

    2014-04-01

    Full Text Available The stem of Acer tegmentosum has been widely used in Korea for the treatment of hepatic disorders. In this study, we investigated the bone protective effect of water extract of the stem of Acer tegmentosum (WEAT. We found that WEAT inhibits osteoclast differentiation induced by receptor activator of nuclear factor-?B ligand (RANKL, an essential cytokine for osteoclast differentiation. In osteoclast precursor cells, WEAT inhibited RANKL-induced activation of JNK, NF-?B, and cAMP response element-binding protein, leading to suppression of the induction of c-Fos and nuclear factor of activated T cells cytoplasmic 1, key transcription factors for osteoclast differentiation. In addition, WEAT inhibited bone resorbing activity of mature osteoclasts. Furthermore, the oral administration of WEAT reduced RANKL-induced bone resorption and trabecular bone loss in mice. Taken together, our study demonstrates that WEAT possesses a protective effect on bone destruction by inhibiting osteoclast differentiation and function.

  7. Comparison of Geophysical Model Functions for SAR Wind Speed Retrieval in Japanese Coastal Waters

    Directory of Open Access Journals (Sweden)

    Merete Badger

    2013-04-01

    Full Text Available This work discusses the accuracies of geophysical model functions (GMFs for retrieval of sea surface wind speed from satellite-borne Synthetic Aperture Radar (SAR images in Japanese coastal waters characterized by short fetches and variable atmospheric stability conditions. In situ observations from two validation sites, Hiratsuka and Shirahama, are used for comparison of the retrieved sea surface wind speeds using CMOD (C-band model4, CMOD_IFR2, CMOD5 and CMOD5.N. Of all the geophysical model functions (GMFs, the latest C-band GMF, CMOD5.N, has the smallest bias and root mean square error at both sites. All of the GMFs exhibit a negative bias in the retrieved wind speed. In order to understand the reason for this bias, all SAR-retrieved wind speeds are separated into two categories: onshore wind (blowing from sea to land and offshore wind (blowing from land to sea. Only offshore winds were found to exhibit the large negative bias, and short fetches from the coastline may be a possible reason for this. Moreover, it is clarified that in both the unstable and stable conditions, CMOD5.N has atmospheric stability effectiveness, and can keep the same accuracy with CMOD5 in the neutral condition. In short, at the moment, CMOD5.N is thought to be the most promising GMF for the SAR wind speed retrieval with the atmospheric stability correction in Japanese coastal waters, although there is ample room for future improvement for the effect from short fetch.

  8. Dry under water: comparative morphology and functional aspects of air-retaining insect surfaces.

    Science.gov (United States)

    Balmert, Alexander; Florian Bohn, Holger; Ditsche-Kuru, Petra; Barthlott, Wilhelm

    2011-04-01

    Superhydrophobic surfaces prevent certain body parts of semiaquatic and aquatic insects from getting wet while submerged in water. The air layer on these surfaces can serve the insects as a physical gill. Using scanning electron microscopy, we investigated the morphology of air-retaining surfaces in five insect species with different levels of adaptation to aquatic habitats. We found surfaces with either large and sparse hairs (setae), small and dense hairs (microtrichia), or hierarchically structured surfaces with both types of hairs. The structural parameters and air-film persistence of these surfaces were compared. Air-film persistence varied between 2 days in the beetle Galerucella nymphaea possessing only sparse setae and more than 120 days in the bugs Notonecta glauca and Ilyocoris cimicoides possessing dense microtrichia (up to 6.6 × 10(6) microtrichia per millimeter square). From our results, we conclude that the density of the surface structures is the most important factor that affects the persistence of air films. Combinations of setae and microtrichia are not decisive for the overall persistence of the air film but might provide a thick air store for a short time and a thin but mechanically more stable air film for a long time. Thus, we assume that a dense cover of microtrichia acts as a "backup system" preventing wetting of the body surface in case the air-water interface is pressed toward the surface. Our findings might be beneficial for the development of biomimetic surfaces for long-term air retention and drag reduction under water. In addition, the biological functions of the different air retention capabilities are discussed. PMID:21290417

  9. Density functional theory study on water-gas-shift reaction over molybdenum disulfide

    DEFF Research Database (Denmark)

    Shi, X. R.; Wang, Shengguang

    2009-01-01

    Density functional theory calculations have been carried out to investigate the adsorption of reaction intermediates appearing during water-gas-shift reaction at the sulfur covered MoS2 (1 0 0)surfaces, Mo-termination with 37.5% S coverage and S-termination with 50% S coverage using periodic slabs. The pathway for water-gas-shift reaction on both terminations has been carefully studied where the most favorable reaction path precedes the redox mechanism, namely the reaction takes place as follows: CO + H2O --> CO + OH + H --> CO + O + 2H --> CO2 + H-2. The most likely reaction candidates for the formate species HCOO formation is the surface CO2 reaction with H as a side reaction of CO2 desorption on S-termination with 50% S coverage. The formed HCOO species will react further with adsorbed hydrogen yielding H2COO followed by breaking its C-O bond to form the surface CH2O and O species.

  10. Nanoporous membranes with cellulose nanocrystals as functional entity in chitosan: removal of dyes from water.

    Science.gov (United States)

    Karim, Zoheb; Mathew, Aji P; Grahn, Mattias; Mouzon, Johanne; Oksman, Kristiina

    2014-11-01

    Fully biobased composite membranes for water purification were fabricated with cellulose nanocrystals (CNCs) as functional entities in chitosan matrix via freeze-drying process followed by compacting. The chitosan (10 wt%) bound the CNCs in a stable and nanoporous membrane structure with thickness of 250-270 ?m, which was further stabilized by cross-linking with gluteraldehyde vapors. Scanning electron microscopy (SEM) studies revealed well-individualized CNCs embedded in a matrix of chitosan. Brunauer, Emmett and Teller (BET) measurements showed that the membranes were nanoporous with pores in the range of 13-10nm. In spite of the low water flux (64 Lm(-2) h(-1)), the membranes successfully removed 98%, 84% and 70% respectively of positively charged dyes like Victoria Blue 2B, Methyl Violet 2B and Rhodamine 6G, after a contact time of 24h. The removal of dyes was expected to be driven by the electrostatic attraction between negatively charged CNCs and the positively charged dyes. PMID:25129796

  11. Defluoridation of water using chitosan assisted ethylenediamine functionalized synthetic polymeric blends.

    Science.gov (United States)

    Prabhu, Subbaiah Muthu; Viswanathan, Natrayasamy; Meenakshi, Sankaran

    2014-09-01

    In this paper, a new kind of approach undertakes for the synthesis of novel chitosan (CS) blended with ethylenediamine (ED) functionalized synthetic polymers viz., acrylonitrile/divinylbenzene/vinylbenzyl chloride (CS@AN/DVB/VBC-ED) and styrene/divinylbenzene/vinylbenzyl chloride (CS@ST/DVB/VBC-ED) for defluoridation of water. Under batch mode, various influencing parameters like shaking time, pH, competitor ions and temperature were optimized. The fluoride removal was reasonably explained using Freundlich, Langmuir and D-R isotherms. The thermodynamic parameters viz., ?G°, ?H° and ?S° indicates the nature of the fluoride sorption with the sorbents. The FT-IR, XRD and SEM with EDAX analysis were used to study the fluoride adsorption of CS@AN/DVB/VBC-ED and CS@ST/DVB/VBC-ED blends. The thermal stability of both the sorbents was tested using TGA/DSC analysis. Studies were also conducted to test the potential application of the prepared polymeric blends for fluoride removal from field water collected from the nearby fluoride endemic area. PMID:25036602

  12. Water adsorption on SrTiO3(001): A density-functional theory study

    International Nuclear Information System (INIS)

    SrTiO3 is a technological oxide, with applications as photo-catalyst, gas-sensor or as substrate for film growth. In many of these applications the surface of SrTiO3 is deliberately or unintended in contact with water molecules. Aiming for the atomic-scale details of this interaction we perform density-functional theory calculations addressing the adsorption of H2O on both regular terminations of the SrTiO3(001) surface. We find that the binding energetics is crucially controlled by long-range surface relaxations. Using this energetics to construct a thermodynamic phase diagram we obtain a different propensity for hydroxylation of the two terminations that is consistent with recent experiments by Iwahori et al. Around room temperature the SrO-termination becomes hydroxylated already at lowest background humidity, whereas the TiO2-terminated domains stay practically water-free in the range of low and moderate H2O vapor pressures.

  13. Effect of combined function of temperature and water activity on the growth of Vibrio harveyi

    Scientific Electronic Library Online (English)

    Kang, Zhou; Meng, Gui; Pinglan, Li; Shaohua, Xing; Tingting, Cui; Zhaohui, Peng.

    2012-12-01

    Full Text Available Vibrio harveyi is considered as a causative agent of the systemic disease, vibriosis, which occurs in many biological fields. The effects of temperatures (12.9-27.1 ºC) and water activity (NaCl% 0.6%-3.4%) on V. harveyi were investigated. The behavior and growth characteristics of V. harveyi was stu [...] died and modeled. Growth curves were fitted by using Gompertz and Baranyi models, and the Baranyi model showed a better fittness. Then, the maximum growth rates (µmax) and lag phase durations (LPD, ?) obtained from both Gompertz and Baranyi model were modeled as a combination function of temperature and water activity using the response surface and Arrhenius-Davey models for secondary model. The value of r², MSE, bias and accuracy factor suggest Baranyi model has better fitness than Gompertz model. Furthermore, validation of the developed models with independent data from ComBase also shown better interrelationship between observed and predicted growth parameter when using Baranyi model.

  14. Atypical water lattices and their possible relevance to the amorphous ices: A density functional study

    Directory of Open Access Journals (Sweden)

    David J. Anick

    2013-04-01

    Full Text Available Of the fifteen known crystalline forms of ice, eleven consist of a single topologically connected hydrogen bond network with four H-bonds at every O. The other four, Ices VI–VIII and XV, consist of two topologically connected networks, each with four H-bonds at every O. The networks interpenetrate but do not share H-bonds. This article presents two new periodic water lattice families whose topological connectivity is “atypical”: they consist of many two-dimensional layers that share no H-bonds. Layers are held together only by dispersion forces. Within each layer there are still four H-bonds at each O. Called “Hexagonal Bilayer Water” (HBW and “Pleated Sheet Water” (PSW, they have computed densities of about 1.1 g/mL and 1.3 g/mL respectively, and nearest neighbor O-coordination is 4.5 to 5.5 and 6 to 8 respectively. Using density functional theory (BLYP-D/TZVP, various proton ordered forms of HBW and PSW are optimized and categorized. There are simple pathways connecting Ice-Ih to HBW and HBW to PSW. Their computed properties suggest similarities to the high density and very high density amorphous ices (HDA and VHDA respectively. It is unknown whether HDA, VHDA, and Low Density Amorphous Ice (LDA are fully disordered glasses down to the molecular level, or whether there is some short-range local order. Based on estimated radial distribution functions (RDFs, one proton ordered form of HBW matches HDA best. The idea is explored that HDA could contain islands with this underlying structure, and likewise, that VHDA could contain regions of PSW. A “microlattice model version 1” (MLM1 is presented as a device to compare key experimental data on the amorphous ices with these atypical structures and with a microlattice form of Ice-XI for LDA. Resemblances are found with the amorphs’ RDFs, densities, Raman spectra, and transition behaviors. There is not enough information in the static models to assign either a microlattice structure or a partial microlattice structure to any amorphous ice phase.

  15. General displaced SU(1, 1) number states: Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Dehghani, A., E-mail: alireza.dehghani@gmail.com, E-mail: a-dehghani@tabrizu.ac.ir [Physics Department, Payame Noor University, P.O. Box 19395-3697 Tehran (Iran, Islamic Republic of)

    2014-04-15

    The most general displaced number states, based on the bosonic and an irreducible representation of the Lie algebra symmetry of su(1, 1) and associated with the Calogero-Sutherland model are introduced. Here, we utilize the Barut-Girardello displacement operator instead of the Klauder-Perelomov counterpart, to construct new kind of the displaced number states which can be classified in nonlinear coherent states regime, too, with special nonlinearity functions. They depend on two parameters, and can be converted into the well-known Barut-Girardello coherent and number states, respectively, depending on which of the parameters equal to zero. A discussion of the statistical properties of these states is included. Significant are their squeezing properties and anti-bunching effects which can be raised by increasing the energy quantum number. Depending on the particular choice of the parameters of the above scenario, we are able to determine the status of compliance with flexible statistics. Major parts of the issue is spent on something that these states, in fact, should be considered as new kind of photon-added coherent states, too. Which can be reproduced through an iterated action of a creation operator on new nonlinear Barut-Girardello coherent states. Where the latter carry, also, outstanding statistical features.

  16. SIFT flow for large-displacement object tracking.

    Science.gov (United States)

    Zhang, Huanlong; Hu, Shiqiang; Zhang, Xiaoyu

    2014-09-20

    Traditional tracking methods place an emphasis on how to cope with the variations in target appearance effectively. However, when the motion displacement of the target between image frames becomes larger, these methods may be unstable. This paper presents a novel (to our knowledge) visual object tracking method. In this method, we first introduce scale-invariant feature transform (SIFT) flow into the tracking problem and develop a real-time motion prediction method to capture large displacement between consecutive image frames. Then we use belief propagation (BP) to convert the problem of finding maximum a posteriori probability (MAP) to globally minimizing an energy function to get the best matching pairs of points for producing good candidate regions of the target. And last, the refined point trajectories are obtained according to the bidirectional flow field consistency estimation and covariance region descriptor matching, which can update model states efficiently so as to achieve enhanced robustness for visual tracking. Compared with the state-of-art tracking methods, the experimental results demonstrate that the proposed algorithm shows favorable performance when the object undergoes large motion displacement between image frames. PMID:25322097

  17. A mathematical model of the shore level displacement in Fennoscandia

    International Nuclear Information System (INIS)

    The shore level displacement in Fennoscandia (Scandinavia and Finland) is mainly due to two cooperative vertical movements, the glacio-isostatic uplift and the eustatic sea level rise. The course of the glacio-isostatic uplift has recently been made discernible according to an investigation of the lake tilting phenomenon. This new information has made it possible to start an iteration process for detailed estimations of the uplift and the rise using empirical data of the shore level displacement. Arctan-functions have proved to be suitable tools for describing the glacio-isostatic uplift. The model indicates that there are two mechanisms involved in the glacio-isostatic uplift, one slow that can be linked to viscous flow, and one fast that might be explained by compression followed by decompression. The future development regarding the glacio-isostatic uplift, the eustasy and the shore level displacement is predicted in Fennoscandia using the results from the modeling. The predictions are based on the assumption that the crustal and eustatic developments will follow the trends that exist today. 124 refs, 98 figs

  18. Distribution of particle displacements due to swimming microorganisms

    Science.gov (United States)

    Thiffeault, Jean-Luc

    2015-08-01

    The experiments of Leptos et al. [Phys. Rev. Lett. 103, 198103 (2009), 10.1103/PhysRevLett.103.198103] show that the displacements of small particles affected by swimming microorganisms achieve a non-Gaussian distribution, which nevertheless scales diffusively—the "diffusive scaling." We use a simple model where the particles undergo repeated "kicks" due to the swimmers to explain the shape of the distribution as a function of the volume fraction of swimmers. The net displacement is determined by the inverse Fourier transform of a single-swimmer characteristic function. The only adjustable parameter is the strength of the stresslet term in our spherical squirmer model. We give a criterion for convergence to a Gaussian distribution in terms of moments of the drift function and show that the experimentally observed diffusive scaling is a transient related to the slow crossover of the fourth moment from a ballistic to a linear regime with path length. We also present a simple model, with logarithmic drift function, that can be solved analytically.

  19. Atomic displacements in bcc dilute alloys

    Indian Academy of Sciences (India)

    Hitesh Sharma; S Prakash

    2007-04-01

    We present here a systematic investigation of the atomic displacements in bcc transition metal (TM) dilute alloys. We have calculated the atomic displacements in bcc (V, Cr, Fe, Nb, Mo, Ta and W) transition metals (TMs) due to 3d, 4d and 5d TMs at the substitutional site using the Kanzaki lattice static method. Wills and Harrison interatomic potential is used to calculate the atomic force constants, the dynamical matrix and the impurity-induced forces. We have thoroughly investigated the atomic displacements using impurities from 3d, 4d and 5d series in the same host metal and the same impurity in different hosts. We have observed a systematic pattern in the atomic displacements for Cr-, Fe-, Nb-, Mo-, Ta- and W-based dilute alloys. The atomic displacements are found to increase with increase in the number of d electrons for all alloys considered except for V dilute alloys. The 3d impurities are found to be more easily dissolved in the 3d host metals than 4d or 5d TMs whereas 4d and 5d impurities show more solubility in 4d and 5d TMs. In general, the relaxation energy calculation suggests that impurities may be easily solvable in 5d TM hosts when compared to 3d or 4d TMs.

  20. Effects of viruses on bacterial functions under contrasting nutritional conditions for four species of bacteria isolated from Hong Kong waters

    Science.gov (United States)

    Liu, Hao; Yuan, Xiangcheng; Xu, Jie; Harrison, Paul J.; He, Lei; Yin, Kedong

    2015-09-01

    Free living viruses are ubiquitous in marine waters and concentrations are usually several times higher than the bacterial abundance. These viruses are capable of lysing host bacteria and therefore, play an important role in the microbial loop in oligotrophic waters. However, few studies have been conducted to compare the role of viruses in regulating bacterial abundance and heterotrophic activities between natural oligotrophic waters and anthropogenic influenced eutrophic waters. In this study, we examined viral effects on bacterial functions of four single bacterial species incubated with natural viral assemblages in seawater samples from eutrophic and oligotrophic waters. The viral-lysis of bacteria was significantly higher in eutrophic than oligotrophic waters. This suggests that viruses were capable of controlling bacterial abundance, respiration and production in the eutrophic waters. Cellular bacterial respiration and production was higher with viruses than without viruses, which was more evident in the oligotrophic waters. These results indicate that viruses can slow down bacterial consumption of oxygen and reduce bacteria-induced eutrophication effects in anthropogenic eutrophic waters, but switch to the role of sustaining the bacterial population when nutrients are limiting. There were bacterial species differences in resisting viral attack, which can influence the dominance and biodiversity of bacterial species in coastal waters.

  1. Stimulatory Effects of Balanced Deep Sea Water on Mitochondrial Biogenesis and Function.

    Science.gov (United States)

    Ha, Byung Geun; Park, Jung-Eun; Cho, Hyun-Jung; Shon, Yun Hee

    2015-01-01

    The worldwide prevalence of metabolic diseases, including obesity and diabetes, is increasing. Mitochondrial dysfunction is recognized as a core feature of these diseases. Emerging evidence also suggests that defects in mitochondrial biogenesis, number, morphology, fusion, and fission, contribute to the development and progression of metabolic diseases. Our previous studies revealed that balanced deep-sea water (BDSW) has potential as a treatment for diabetes and obesity. In this study, we aimed to investigate the mechanism by which BDSW regulates diabetes and obesity by studying its effects on mitochondrial metabolism. To determine whether BDSW regulates mitochondrial biogenesis and function, we investigated its effects on mitochondrial DNA (mtDNA) content, mitochondrial enzyme activity, and the expression of transcription factors and mitochondria specific genes, as well as on the phosphorylation of signaling molecules associated with mitochondria biogenesis and its function in C2C12 myotubes. BDSW increased mitochondrial biogenesis in a time and dose-dependent manner. Quantitative real-time PCR revealed that BDSW enhances gene expression of PGC-1?, NRF1, and TFAM for mitochondrial transcription; MFN1/2 and DRP1 for mitochondrial fusion; OPA1 for mitochondrial fission; TOMM40 and TIMM44 for mitochondrial protein import; CPT-1? and MCAD for fatty acid oxidation; CYTC for oxidative phosphorylation. Upregulation of these genes was validated by increased mitochondria staining, CS activity, CytC oxidase activity, NAD+ to NADH ratio, and the phosphorylation of signaling molecules such as AMPK and SIRT1. Moreover, drinking BDSW remarkably improved mtDNA content in the muscles of HFD-induced obese mice. Taken together, these results suggest that the stimulatory effect of BDSW on mitochondrial biogenesis and function may provide further insights into the regulatory mechanism of BDSW-induced anti-diabetic and anti-obesity action. PMID:26068191

  2. WATER MANAGEMENT PROBLEMS AT THE BUKÓWKA DRINKING WATER RESERVOIR’S CROSS-BORDER BASIN AREA IN TERMS OF ITS ESTABLISHED FUNCTIONS

    Directory of Open Access Journals (Sweden)

    Miros?aw Wiatkowski

    2015-02-01

    Full Text Available The paper covers the analysis of water management problems in the cross-border reservoir basin of Bukówka, located at the Bóbr river, at 271+540 km of its course, below the Czech-Polish border, in Dolno?l?skie Voivodeship. The problems of water management in the context of the reservoir’s functions have been analyzed; these are: flood control, the provision of water during low water level periods for the Water Treatment Plant in Marciszów, the provision of drinking water for the city of Wa?brzych as well as the provision of proper flow in the Bóbr river bed downstream from the reservoir. Due to its localization right below the border with the Czech Republic, the reservoir is exposed to a number of problems. The study has found that the main problems of water management in the basin area included unsatisfactory state of water and wastewater management in the basin, unsatisfactory state of the surface water quality in the basin area of the reservoir, poor condition of streams and drainage ditches, improper arrangement of arable lands and large downslopes and a lack of monitoring stations on tributaries of the reservoir. It has been found that the hydrochemical conditions in the Bukówka reservoir’s section are unfavorable for it. From the eutrophication point of view, the water flowing into the tank is characterized by a large content of nutrients, especially nitrates, phosphates and BOD5. In order to counteract eutrophication it is necessary to lower the concentration of nutrients in the water flowing into the tank. One of the basic ways to do so is to restore the water and wastewater management in the reservoir’s basin. Studies in the Bukówka reservoir provide important information concerning the state of the purity of the water supplying the reservoir. In order to obtain accurate information on the state of purity, a monitoring of hydrological and water quality should be continued. The studies are a part of the strategy of protection of the quality of transboundary waters, proposed in the Convention on the Protection and Use of Transboundary Watercourses and International Lakes of 1992.

  3. Immersion freezing of water and aqueous ammonium sulphate droplets initiated by Humic Like Substances as a function of water activity

    OpenAIRE

    Y. J. Rigg; P. A. Alpert; Knopf, D. A.

    2013-01-01

    Immersion freezing of water and aqueous (NH4)2SO4 droplets containing Leonardite (LEO) and Pahokee peat (PP) serving as surrogates for Humic Like Substances (HULIS) has been investigated. Organic aerosol containing HULIS are ubiquitous in the atmosphere, however, their potential for ice cloud formation is uncertain. Immersion freezing has been studied for temperatures as low as 215 K and solution water activity,

  4. Study of degenerate parabolic system modeling the hydrogen displacement in a nuclear waste repository

    OpenAIRE

    Caro, Florian; Saad, Bilal; Saad, Mazen

    2012-01-01

    Our goal is the mathematical analysis of a two phase (liquid and gas) two components (water and hydrogen) system modeling the hydrogen displacement in a storage site for radioactive waste. We suppose that the water is only in the liquid phase and is incompressible. The hydrogen in the gas phase is supposed compressible and could be dissolved into the water with the Henry's law. The flow is described by the conservation of the mass of each components. The model is treated wit...

  5. Incorporation of water into olivine during nebular condensation: Insights from density functional theory and thermodynamics, and implications for phyllosilicate formation and terrestrial water inventory

    Science.gov (United States)

    Asaduzzaman, Abu; Muralidharan, Krishna; Ganguly, Jibamitra

    2015-04-01

    Using density functional theory, we have examined the hydration mechanism of olivine with the objective of understanding the reaction pathways toward the formation of crystalline serpentine and brucite. It is found that further supply of water beyond saturation of the adsorption sites on olivine surfaces leads to the formation of amorphous brucite and serpentine molecules, with the latter forming in the subsurface domain. The calculated activation energy for this process is ~25 kJ mol-1, which permits formation of the amorphous materials well within the life span of the solar nebula. In addition, molecular dynamic simulations show that the adsorbed water in olivine is stable at least up to 900 K—a finding that is in accord with independent experimental studies. Thus, adsorption plus subsurface reaction of H2O in olivine could have taken place at temperatures considerably higher than the stability limit of hydrous minerals in the nebular condition. Using the DFT derived enthalpy of adsorption data, and reasonable approximation for the entropy of adsorption, we have calculated the fractional coverage of the reactive surface sites of olivine grains of spherical geometry by adsorbed water, and the corresponding ocean equivalent water (OEW) that could have been accreted into the Earth. These results suggest that adsorption and the associated subsurface hydroxylation of olivine grains might have been responsible for a significant fraction of the Earth's water budget. The adsorption of water into olivine crystals in the solar nebula might also have led to the delivery of water to other planetary bodies.

  6. Relationships between leaf anatomy, morphology, and water use efficiency in Aloe vera (L) Burm f. as a function of water availability

    Scientific Electronic Library Online (English)

    Herman, Silva; Susana, Sagardia; Mauricio, Ortiz; Nicolás, Franck; Marcela, Opazo; Madeleine, Quiroz; Cecilia, Baginsky; Cristián, Tapia.

    Full Text Available The effects of water availability were evaluated on the photosynthetic tissue anatomy in Aloe vera(L) Burm f. and its relationship with morphological, physiological parameters, and water use efficiency as a function of aerial biomass and gel production. Plants were subjected to four levels of water [...] availability equivalent to 20% (T1), 15% (T2), 10% (T3), and 5% (T4) of the atmospheric evaporative demand. The plants exhibited anatomical, morphological, and physiological responses to the different watering treatments. The extreme treatments produced negative responses due to excess water in T1 and water deficit in T4. Treatments T2 and T3 elicited positive responses in cell characteristics and productivity. Anatomical and structural characteristics were closely linked to physiology. Increased stomata number was negatively related to leaf length, width, and thickness (r = -0.85, -0.81, and -0.59, respectively) and to biomass production (r = -0.84), and positively related to the increase of cuticle thickness (r = 0.78). Treatment T2 showed the maximum efficiency of water use for biomass production (24.6 g L-1), which was closely related to cell size (r = 0.68) and number of stomata (r = -0.70).

  7. Imaging of small radioactive point source displacement

    International Nuclear Information System (INIS)

    A new technique for three dimensional recording of a patient mandibular movement is described. A small and harmless radioactive source is fixed at the point of interest. Using proper collimation, the motion of the point source is recorded via a gamma camera and minicomputer. Image enhancement techniques are used and physiological displacement is reproduced. We measured the vertical, lateral and protrusive envelopes of motion of a point on a tooth from a full denture set mounted on a semiadjustable articulator. All displacements were calibrated. Multiple sources in a single experiment may be recorded to describe the displacement of several points of interest. First experiments were run on patients. This method, derived from Nuclear Medicine techniques, offers a powerful tool of general interest for the tracking of dynamic events in many fields of Dental Medicine, for instance temporo-mandibular joint disfunction as well as Prosthetics. (author)

  8. Displacement Cascade Damage Production in Metals

    Energy Technology Data Exchange (ETDEWEB)

    Stoller, Roger E [ORNL; Malerba, Lorenzo [Belgian Nuclear Research Centre, SCK-CEN; Nordlund, Kai [University of Helsinki

    2015-01-01

    Radiation-induced changes in microstructure and mechanical properties in structural materials are the result of a complex set of physical processes initiated by the collision between an energetic particle (neutron or ion) and an atom in the lattice. This primary damage event is called an atomic displacement cascade. The simplest description of a displacement cascade is to view it as a series of many billiard-ball-like elastic collisions among the atoms in the material. This chapter describes the formation and evolution of this primary radiation damage mechanism to provide an overview of how stable defects are formed by displacement cascades, as well as the nature and morphology of the defects themselves. The impact of the relevant variables such as cascade energy and irradiation temperature is discussed, and defect formation in different materials is compared.

  9. Performance of displacement ventilation in practice

    DEFF Research Database (Denmark)

    Naidenov, K.; Pitchurov, G.

    2002-01-01

    This paper presents results of a field study in offices with displacement ventilation. It comprises detailed physical measurements of the thermal environment and collection of occupants´ response at 227 workplaces. The results, both physical measurements and human response, identified draught as the major local discomfort in the rooms with displacement ventilation. Twenty-three percent of the occupants were daily bothered by draught. In some buildings the maintenance personnel tried to improve occupants´ thermal comfort by raising the supply air temperature or office workers themselves blocked the diffusers by rearranging the furniture. Half of the surveyed occupants were not satisfied with the indoor air quality. The main conclusion is that displacement ventilation needs careful design and room furnishing in order to ensure a comfortable environment. Occupants must understand the underlying ventilation principle. This will ensure proper and efficient operation of the system and occupants´ satisfaction.

  10. Modelling of the Vajont rockslide displacements by delayed plasticity of interacting sliding blocks

    Science.gov (United States)

    Castellanza, riccardo; Hedge, Amarnath; Crosta, Giovanni; di Prisco, Claudio; Frigerio, Gabriele

    2015-04-01

    In order to model complex sliding masses subject to continuous slow movements related to water table fluctuations it is convenient to: i) model the time-dependent mechanical behaviour of the materials by means of a viscous-plastic constitutive law; ii) assume the water table fluctuation as the main input to induce displacement acceleration; iii) consider, the 3D constrains by maintaining a level of simplicity such to allow the implementation into EWS (Early Warning System) for risk management. In this work a 1D pseudo-dynamic visco-plastic model (Secondi et al. 2011), based on Perzyna's delayed plasticity theory is applied. The sliding mass is considered as a rigid block subject to its self weight, inertial forces and seepage forces varying with time. All non-linearities are lumped in a thin layer positioned between the rigid block and the stable bedrock. The mechanical response of this interface is assumed to be visco-plastic. The viscous nucleus is assumed to be of the exponential type, so that irreversible strains develop for both positive and negative values of the yield function; the sliding mass is discretized in blocks to cope with complex rockslide geometries; the friction angle is assumed to reduce with strain rate assuming a sort of strain - rate law (Dietrich-Ruina law). To validate the improvements introduced in this paper the simulation of the displacements of the Vajont rockslide from 1960 to the failure, occurred on October the 9th 1963, is perfomed. It will be shown that, in its modified version, the model satisfactorily fits the Vajont pre-collapse displacements triggered by the fluctuation of the Vajont lake level and the associated groundwater level. The model is able to follow the critical acceleration of the motion with a minimal change in friction properties.The discretization in interacting sliding blocks confirms its suitability to model the complex 3D rockslide behaviour. We are currently implementing a multi-block model capable to include the mutual influence of multiple blocks, characterized by different geometry and groundwater levels, shear zone properties and type of interconnection. Secondi M., Crosta G., Di Prisco C., Frigerio G., Frattini P., Agliardi F. (2011) "Landslide motion forecasting by a dynamic visco-plastic model", Proc. The Second World Landslide Forum, L09 - Advances in slope modelling, Rome, 3-9 October 2011, paper WLF2-2011-0571

  11. Displacement, asymmetric information and heterogeneous human capital

    OpenAIRE

    Hu, Luojia; Taber, Christopher

    2008-01-01

    In a seminal paper Gibbons and Katz (1991; GK) develop and empirically test an asymmetric information model of the labor market. The model predicts that wage losses following displacement should be larger for layoffs than for plant closings, which was borne out by data from the Displaced Workers Survey (DWS). In this paper, we take advantage of many more years of DWS data to examine how the difference in wage losses across plant closing and layoff varies with race and gender. We find that the...

  12. Precision calibration of a laser displacement sensor

    Science.gov (United States)

    Irvin, Bradley

    2013-10-01

    Surface current coils with extremely precise magnetic fields can be designed using the magnetic scalar potential. These coils are constructed as curved 3-dimensional printed circuit boards with traces flowing along the equipotential contours. We are preparing to manufacture such coils using a high speed precision spindle controlled by a Staubli RX130 6 axis robotic arm. A laser displacement sensor is used to calibrate the robot and to determine the position of the circuit board substrate for accurate construction. In this poster, we describe a procedure to calibrate the laser displacement sensor to an accuracy of a few microns using linear least squares fits to the position of two coupled linear stages.

  13. Atomic displacement distribu< on during ion irradiation

    International Nuclear Information System (INIS)

    The method to plot atomic displacement distribution in depth of solids irradiated by ions is suggested. This method leads to better agreement between measured dependences of displacement density on the depth and the sputtering factor per shooting on the target thickness in comparing with the known theory of linear cascades. The experimental results given in the paper and obtained for tungsten irradiated by iron ions (5 keV energy) are in satisfactorily agreement with theoretical data calculated according to the method suggested. 9 refs.; 2 figs.; 1 tab

  14. Spatial patterning of water quality in Biscayne Bay, Florida as a function of land use and water management.

    Science.gov (United States)

    Caccia, Valentina G; Boyer, Joseph N

    2005-11-01

    An objective classification analysis was performed on a water quality data set from 25 sites collected monthly during 1994-2003. The water quality parameters measured included: TN, TON, DIN, NH4+, NO3-, NO2-, TP, SRP, TN:TP ratio, TOC, DO, CHL A, turbidity, salinity and temperature. Based on this spatial analysis, Biscayne Bay was divided into five zones having similar water quality characteristics. A robust nutrient gradient, driven mostly by dissolved inorganic nitrogen, from alongshore to offshore in the main Bay, was a large determinant in the spatial clustering. Two of these zones (Alongshore and Inshore) were heavily influenced by freshwater input from four canals which drain the South Dade agricultural area, Black Point Landfill, and sewage treatment plant. The North Bay zone, with high turbidity, phytoplankton biomass, total phosphorus, and low DO, was affected by runoff from five canals, the Munisport Landfill, and the urban landscape. The South Bay zone, an embayment surrounded by mangrove wetlands with little urban development, was high in dissolved organic constituents but low in inorganic nutrients. The Main Bay was the area most influenced by water exchange with the Atlantic Ocean and showed the lowest nutrient concentrations. The water quality in Biscayne Bay is therefore highly dependent of the land use and influence from the watershed. PMID:16194552

  15. Effect of Body Mass Index on Intrafraction Prostate Displacement Monitored by Real-Time Electromagnetic Tracking

    International Nuclear Information System (INIS)

    Purpose: To evaluate, using real-time monitoring of implanted radiofrequency transponders, the intrafraction prostate displacement of patients as a function of body mass index (BMI). Methods and Materials: The motions of Beacon radiofrequency transponders (Calypso Medical Technologies, Seattle, WA) implanted in the prostate glands of 66 men were monitored throughout the course of intensity modulated radiation therapy. Data were acquired at 10 Hz from setup to the end of treatment, but only the 1.7 million data points with a “beam on” tag were used in the analysis. There were 21 obese patients, with BMI ?30 and 45 nonobese patients in the study. Results: Mean displacements were least in the left-right lateral direction (0.56 ± 0.24 mm) and approximately twice that magnitude in the superior-inferior and anterior-posterior directions. The net vector displacement was larger still, 1.95 ± 0.47 mm. Stratified by BMI cohort, the mean displacements per patient in the 3 Cartesian axes as well as the net vector for patients with BMI ?30 were slightly less (<0.2 mm) but not significantly different than the corresponding values for patients with lower BMIs. As a surrogate for the magnitude of oscillatory noise, the standard deviation for displacements in all measured planes showed no significant differences in the prostate positional variability between the lower and higher BMI groups. Histograms of prostate displacements showed a lower frequency of large displacements in obese patients, and there were no significant differences in short-term and long-term velocity distributions. Conclusions: After patients were positioned accurately using implanted radiofrequency transponders, the intrafractional displacements in the lateral, superior-inferior, and anterior-posterior directions as well as the net vector displacements were smaller, but not significantly so, for obese men than for those with lower BMI.

  16. Do displacement activities help preschool children to inhibit a forbidden action?

    Science.gov (United States)

    Pecora, Giulia; Addessi, Elsa; Schino, Gabriele; Bellagamba, Francesca

    2014-10-01

    Displacement activities are commonly recognized as behavioral patterns, mostly including self-directed actions (e.g., scratching, self-touching), that often occur in situations involving conflicting motivational tendencies. In ethology, several researchers have suggested that displacement activities could facilitate individuals in dealing with the stress experienced in a frustrating context. In child developmental research, some authors have assessed whether distraction strategies could help children to inhibit a dominant response during delay of gratification tasks. However, little is known about the displacement activities that young children may produce in such situations. This study was aimed at investigating whether displacement activities had an effect on preschool children's ability to postpone an immediate gratification (i.e., interacting with an attractive toy, a musical box), thereby functioning as regulators of their emotional state. To this end, we administered 143 2- to 4-year-olds with a delay maintenance task and related their performance with displacement activities they produced during the task and with actions with an external object. Children's latency to touch the musical box was positively related to their rate of displacement activities. However, the rate of displacement activities increased progressively as long as the children were able to inhibit the interaction with the musical box. In addition, the rate of displacement activities during the first 1 min of test did not predict the ability of children to inhibit the interaction with the box. These results suggest that displacement activities represented a functionless by-product of motivational conflict rather than a strategy that children used to inhibit their response to an attractive stimulus. PMID:24907630

  17. Novel Pd Catalysts with ?-Diketiminates for Homopolymerization of Functionalized Norbornene Derivatives in Water/Organic Mixed Solvents

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eung Jun; Won, Wook Kyoung; Lee, Byoungkil; Kye, Youn Hee; Lee Ik Mo [Inha Univ., Incheon (Korea, Republic of)

    2013-09-15

    Polynorbornenes prepared by vinyl addition pathway are known to have some desirable characteristics for wider application but they have some critical drawbacks such as brittleness, poor solubility and adhesion. In order to improve these drawbacks, extensive research for the successful homo- and copolymerization of polar functionalized norbornene with olefin has been carried out. Even though considerable advance has been achieved in the polymerization of polar functionalized monomers, successful catalytic systems for the homopolymerization of polar functionalized norbornene are rare. In this study, a novel successful catalytic system for the polymerization of polar functionalized norborene is proposed. This system employs Pd ?-diketiminate/borate cocatalyst in water/organic mixed solvents and it is unique due to introduction of water as a component of solvents. Polymers obtained in this study show high Mw with narrow PDI. Effects of several reaction parameters to the polymer activity and properties are investigated and optimal catalytic system are proposed.

  18. Halothane solvation in water and organic solvents from molecular simulations with new polarizable potential function.

    Science.gov (United States)

    Subbotina, Julia O; Johannes, Jonathan; Lev, Bogdan; Noskov, Sergei Yu

    2010-05-20

    The partitioning of a substrate from one phase into another is a complex process with widespread applications: from chemical technology to the pharmaceutical industry. One particularly well-known and well-studied example is 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) trafficking through the lipid bilayer. Halothane is a model volatile anesthetic known to impact functions of model lipid bilayers, altering the structure and thickness upon its partitioning from the bulk phase. A number of theoretical and experimental investigations suggest the importance of electronic polarizability, determining a preference for halothane to partition in the interfacial systems as in lipid bilayers or binary solvents. The recently published protocol for the development of polarizable force fields based on the classical Drude model has provided fresh impetus to efforts directed at understanding the molecular principles governing complex thermodynamics of the hydrophobic hydration. Here, molecular simulations were combined with free energy simulations to study solvation of halothane in polarizable water and methanol. The absolute free energy of halothane solvation in different solvents (water, methanol, and n-hexane) has been evaluated for additive and polarizable models. It was found that both additive and polarizable models provide an adequate description of the halothane solvation in high-dielectric (polar) solvents such as water, but explicit accounting for electronic polarization is imperative for a correct description of the solvation thermodynamics in nonpolar systems. To study halothane dynamics in binary mixtures, all-atom molecular dynamics (MD) simulations for halothane-methanol mixtures in a wide range of concentrations were performed alongside an analysis of structural organization, dynamics, and thermodynamic properties to dissect the molecular determinants of the halothane solvation in polar and amphiphilic liquids such as methanol. Additionally, a theoretical test of the hypothesis on the weak hydrogen bonding of halothane and methanol in the condensed phase is provided, which was presented on the basis of spectroscopic analysis of the C-H vibrations in different gas-phase complexes. The simulations performed in the condensed phase suggest that hydrophobic interactions between halothane and methanol play a dominant role in preferential solvation. PMID:20411978

  19. Olympic scale of sport-induced displacement

    Directory of Open Access Journals (Sweden)

    Jean du Plessis

    2007-07-01

    Full Text Available The Olympic Games have displaced more than two million people in the last 20 years, disproportionately affecting particular groups such as the homeless, the poor, Roma and African-Americans. Mega-events such as the Olympic Games often leave a negative housing legacy for local populations.

  20. Education: protecting the rights of displaced children

    Directory of Open Access Journals (Sweden)

    Suba Mahalingam

    2002-10-01

    Full Text Available UNICEF and its partners work with displaced communitiesto provide material assistance and protection, using as their basis the UN Convention on the Rights of the Child1 and other internationallegal instruments. Education has proven a valuable tool in this effort, not only making children aware of their rights but also providing a way to participate in the realisation of these rights.

  1. Education: protecting the rights of displaced children

    OpenAIRE

    Suba Mahalingam

    2002-01-01

    UNICEF and its partners work with displaced communitiesto provide material assistance and protection, using as their basis the UN Convention on the Rights of the Child1 and other internationallegal instruments. Education has proven a valuable tool in this effort, not only making children aware of their rights but also providing a way to participate in the realisation of these rights.

  2. Insect Wing Displacement Measurement Using Digital Holography

    International Nuclear Information System (INIS)

    Insects in flight have been studied with optical non destructive techniques with the purpose of using meaningful results in aerodynamics. With the availability of high resolution and large dynamic range CCD sensors the so called interferometric digital holographic technique was used to measure the surface displacement of in flight insect wings, such as butterflies. The wings were illuminated with a continuous wave Verdi laser at 532 nm, and observed with a CCD Pixelfly camera that acquire images at a rate of 11.5 frames per second at a resolution of 1392x1024 pixels and 12 Bit dynamic range. At this frame rate digital holograms of the wings were captured and processed in the usual manner, namely, each individual hologram is Fourier processed in order to find the amplitude and phase corresponding to the digital hologram. The wings displacement is obtained when subtraction between two digital holograms is performed for two different wings position, a feature applied to all consecutive frames recorded. The result of subtracting is seen as a wrapped phase fringe pattern directly related to the wing displacement. The experimental data for different butterfly flying conditions and exposure times are shown as wire mesh plots in a movie of the wings displacement

  3. Internal displacement in Nigeria: an urgent challenge

    Directory of Open Access Journals (Sweden)

    Claudia McGoldrick

    2005-05-01

    Full Text Available In the past five years an estimated 800,000 people have been displaced in Africa’s most populous state. AddressingNigeria’s neglected IDP crisis must be a key priority in the run-up to the country’s 2007 presidential elections.

  4. Iraq: growing needs amid continuing displacement

    Directory of Open Access Journals (Sweden)

    Andrew Harper

    2007-12-01

    Full Text Available Seven months after over 100 country representatives gathered in Geneva to address the Iraq displacement crisis, the humanitarian situation has markedly deteriorated. Expectations that highlighting the burdens of Iraq’s neighbours would result in financial and political support havebeen dashed. Support provided – relative to humanitarianneeds – has been negligible

  5. Displacing Media: LCD LAB Artistic Residency

    Directory of Open Access Journals (Sweden)

    Filipe Pais

    2012-12-01

    Full Text Available This review refers to an artistic residency which took place at LCD LAB -  CAAA at Guimarães, in March, exploring a strategy for media art called Media Displacement. The text introduces the strategy very briefly and describes the residency's organization, structure, processses and the results produced.

  6. Britain's Redundancy Payments for Displaced Workers.

    Science.gov (United States)

    Root, Lawrence S.

    1987-01-01

    The Redundancy Payments Act of 1965 established the idea that an employee has property rights to a job based on years of company service. It instituted an entitlement program for displaced workers sponsored by firms and the government. The British layoff situtation differs from that of the United States. (Author/CH)

  7. Rotational melting in displacive quantum paraelectrics

    International Nuclear Information System (INIS)

    Displacive quantum paraelectrics are discussed as possible realizations of rotational quantum melting. The phenomenology of SrTiO3 and KTaO3 is discussed in this light. Both old and fresh theoretical work on two-dimensional lattice models for quantum paraelectricity is reviewed. (author). 73 refs, 15 figs

  8. Iraq: growing needs amid continuing displacement

    OpenAIRE

    Andrew Harper

    2007-01-01

    Seven months after over 100 country representatives gathered in Geneva to address the Iraq displacement crisis, the humanitarian situation has markedly deteriorated. Expectations that highlighting the burdens of Iraq’s neighbours would result in financial and political support havebeen dashed. Support provided – relative to humanitarianneeds – has been negligible

  9. Displacing Media: LCD LAB Artistic Residency

    OpenAIRE

    Filipe Pais

    2012-01-01

    This review refers to an artistic residency which took place at LCD LAB -  CAAA at Guimarães, in March, exploring a strategy for media art called Media Displacement. The text introduces the strategy very briefly and describes the residency's organization, structure, processses and the results produced.

  10. HTR-10GT AMBs displacement sensor design

    International Nuclear Information System (INIS)

    The 10 MW high temperature gas-cooled test module reactor (HTR-10GT) with the core made of spherical fuel elements was designed and constructed by the Institute of Nuclear and New Energy Technology of Tsinghua University in China. In the HTR-10GT, turbo-compressor and generator rotors are connected by a flexible coupling. The rotors, restricted by actual instruments and working environment, must be supported without any contact and lubrication. Active magnetic bearing (AMB), known as its advantages over the conventional bearings., such as contact-free, no-lubricating and active damping vibration, is the best way to suspend and stabilize the position of rotors of HTR-10GT. Each rotor is suspended by two radial and one axial AMBs. The radial AMB's radial gap is 0.15 mm considering the gap of 0.4 mm between the compressor stator and blades in order to protect the compressor. The control system controls the rotor position to meet the required gaps between rotor and stator through windings current. All the position information concerning radial and axial AMB is generated by sensors for measuring the displacement of the levitated body. Some typical sensors, i.e. eddy current displacement sensor, capacitive displacement sensor, can provide position information, but, quite often, unsatisfactory anti-jamming, which is a key issue for AMB systems near generator and other electric devices in HTR-10GT. Therefore, a kind of new type sensor is designed to measure the radial and axial displacements and the vibration of the rotors. This paper focuses on the design characteristics of the HTR-10GT AMBs displacement sensors and introduction of the related experiments to demonstrate its performance. (authors)

  11. Evaporation Rate of Water as a Function of a Magnetic Field and Field Gradient

    OpenAIRE

    Peng Shang; Ai-Rong Qian; Wei-Hong Guo; Yan Wang; Yue Liu; Huan-Huan Huang; Yong-Ming Liu; Chen-Yan Zhang; Jian-Yu Shi; Da-Chuan Yin; Hui-Ling Cao; Yun-Zhu Guo

    2012-01-01

    The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity lev...

  12. Development of Protein-Functionalized Magnetic Iron Oxide Nanoparticles: Potential Application in Water Treatment

    OpenAIRE

    Okoli, Chuka

    2012-01-01

    The treatment of water to make it safe for human consumption is a problem of immense concern, both in developing and developed countries. However, the production of clean water with chemicals as coagulants has several drawbacks associated with cost, health risks and complexity in sludge management. The application of nanotechnology in water treatment is a fast growing discipline proposed as an efficient alternative that will combat these hurdles. The aim of this thesis is to develop new water...

  13. Water makes the difference: rearrangement of water solvation layer triggers non-additivity of functional group contributions in protein-ligand binding.

    Science.gov (United States)

    Biela, Adam; Betz, Michael; Heine, Andreas; Klebe, Gerhard

    2012-08-01

    The binding of four congeneric peptide-like thermolysin inhibitors has been studied by high-resolution crystal structure analysis and isothermal titration calorimetry. The ligands differ only by a terminal carboxylate and/or methyl group. A surprising non-additivity of functional group contributions for the carboxylate and/or methyl groups is detected. Adding the methyl first and then the carboxylate group results in a small Gibbs free energy increase and minor enthalpy/entropy partitioning for the first modification, whereas the second involves a strong affinity increase combined with large enthalpy/entropy changes. However, first adding the carboxylate and then the methyl group yields reverse effects: the acidic group attachment now causes minor effects, whereas the added methyl group provokes large changes. As all crystal structures show virtually identical binding modes, affinity changes are related to rearrangements of the first solvation layer next to the S(2)' pocket. About 20-25 water molecules are visible next to the studied complexes. The added COO(-) groups perturb the local water network in both carboxylated complexes, and the attached methyl groups provide favorable interaction sites for water molecules. Apart from one example, a contiguously connected water network between protein and ligand functional groups is observed in all complexes. In the complex with the carboxylated ligand, which still lacks the terminal methyl group, the water network is unfavorably ruptured. This results in a surprising thermodynamic signature showing only a minor affinity increase upon COO(-) group attachment. Because the further added methyl group provides a favorable interaction site for water, the network can be reestablished, and a strong affinity increase with a large enthalpy/entropy signature is then detected. PMID:22733601

  14. Water

    Science.gov (United States)

    ... How does lead get into my tap water? Measures taken during the last two decades have greatly reduced exposures to lead in tap water. These measures include actions taken under the requirements of the 1986 and 1996 ...

  15. Displacement and stress fields around rock fractures opened by irregular overpressure variations

    Directory of Open Access Journals (Sweden)

    ShigekazuKusumoto

    2014-05-01

    Full Text Available Many rock fractures are entirely driven open by fluids such as ground water, geothermal water, gas, oil, and magma. These are a subset of extension fractures (mode I cracks; e.g., dikes, mineral veins and joints referred to as hydrofractures. Field measurements show that many hydrofractures have great variations in aperture. However, most analytical solutions for fracture displacement and stress fields assume the loading to be either constant or with a linear variation. While these solutions have been widely used, it is clear that a fracture hosted by heterogeneous and anisotropic rock is normally subject to loading that is neither constant nor with a linear variation. Here we present new general solutions for the displacement and stress fields around hydrofractures, modelled as two-dimensional elastic cracks, opened by irregular overpressure variations given by the Fourier cosine series. Each solution has two terms. The first term gives the displacement and stress fields due to the average overpressure acting inside the crack; it is given by the initial term of the Fourier coefficients expressing the overpressure variation. The second term gives the displacement and stress fields caused by the overpressure variation; it is given by general terms of the Fourier coefficients and solved through numerical integration. Our numerical examples show that the crack aperture variation closely reflects the overpressure variation. Also, that the general displacement and stress fields close to the crack follow the overpressure variation but tend to be more uniform far from the crack. The present solutions can be used to estimate the displacement and stress fields around any fluid-driven crack, that is, any hydrofracture, as well as its aperture, provided the variation in overpressure can be described by Fourier series. The solutions add to our understanding of local stresses, displacements, and fluid transport associated with hydrofractures in the crust.

  16. Conflict, displacement and health in the Middle East.

    Science.gov (United States)

    Mowafi, Hani

    2011-01-01

    Displacement is a hallmark of modern humanitarian emergencies. Displacement itself is a traumatic event that can result in illness or death. Survivors face challenges including lack of adequate shelter, decreased access to health services, food insecurity, loss of livelihoods, social marginalisation as well as economic and sexual exploitation. Displacement takes many forms in the Middle East and the Arab World. Historical conflicts have resulted in long-term displacement of Palestinians. Internal conflicts have driven millions of Somalis and Sudanese from their homes. Iraqis have been displaced throughout the region by invasion and civil strife. In addition, large numbers of migrants transit Middle Eastern countries or live there illegally and suffer similar conditions as forcibly displaced people. Displacement in the Middle East is an urban phenomenon. Many displaced people live hidden among host country populations in poor urban neighbourhoods - often without legal status. This represents a challenge for groups attempting to access displaced populations. Furthermore, health information systems in host countries often do not collect data on displaced people, making it difficult to gather data needed to target interventions towards these vulnerable populations. The following is a discussion of the health impacts of conflict and displacement in the Middle East. A review was conducted of published literature on migration and displacement in the region. Different cases are discussed with an emphasis on the recent, large-scale and urban displacement of Iraqis to illustrate aspects of displacement in this region. PMID:21590557

  17. Water

    Science.gov (United States)

    ... water pollution How to protect yourself from water pollution Air Chemicals Noise Quizzes Links to more information girlshealth glossary girlshealth. ... usually in the water, made up of one cell, and lack true stems, roots, and leaves. Spills ... Source: U.S. Environmental Protection Agency Here are some ...

  18. The elastic layer with a cylindrical hole subjected to a nonuniform axisymmetric radial displacement.

    Science.gov (United States)

    Grissom, D. S.; Michalopoulos, C. D.

    1973-01-01

    A problem in the linear theory of elasticity is considered wherein a layer with a circular cylindrical hole is subjected to a nonuniform axisymmetric radial displacement. The solution utilizes Navier's equations of elasticity which are solved by means of extended Hankel transforms. A special case in which the radial displacement is a linear function of the axial coordinate is presented. Numerical results are given in graphical form for the case when hole radius and layer thickness are equal. The inversion integrals were evaluated numerically using Longman's technique for computing infinite integrals of oscillatory functions.

  19. Using in situ vertical displacements to characterize changes in moisture load

    Science.gov (United States)

    Murdoch, Lawrence C.; Freeman, Clay E.; Germanovich, Leonid N.; Thrash, Colby; DeWolf, Scott

    2015-08-01

    Changes in soil moisture content alter the load on underlying material, and we have developed a technique for characterizing this effect by using an extensometer to measure the displacement caused by the load change. The extensometer is pushed into soil at depths of 5 m or more, and displacement between two anchors separated by ˜1.5 m is measured with a resolution of better than 0.01 ?m (10-8 m). The instrument is sensitive to load changes at the ground surface within a radial distance that is roughly twice its depth, potentially providing a method for averaging changes in water content over hundreds of m2 or more. During a field trial at a site in South Carolina, compressive displacements in unsaturated saprolite were strongly correlated to rainfall with a calibration factor of 0.16 ?m displacement per mm of rainfall ±0.002 ?m/mm (R2 = 0.95). Estimates of the net change in water volume per unit area made using the calibration factor from rainfall were similar to independent estimates of evapotranspiration. The technique was affected by barometric pressure variations, but the sensitivity was less than expected and does not hinder meaningful application. A companion instrument demonstrated the displacement signal was repeatable. This article was corrected on 11 SEP 2015. See the end of the full text for details.

  20. Gas-driven displacement of a liquid in a partially filled radial Hele-Shaw cell.

    Science.gov (United States)

    Ward, Thomas; White, Andrew R

    2011-04-01

    The displacement of liquids from confined geometries by using a gas phase is a problem that is relevant to many technologies. Efficient removal of the liquid phase is achieved when an extremely thin residual fluid film is produced as it is displaced. Here the dynamics of air, at constant pressure, displacing a glycerol-water drop in a radial Hele-Shaw cell is studied in this context at low Reynolds numbers. Empirically derived expressions relating the input parameters (fluid viscosity, pressure, and drop volume) to characteristic gas flow and liquid displacement rates, and the steady-state film thickness, are proposed and compared with experiments. The experiments consist of measuring cross-sectional areas of the penetrating gas (air) and displaced liquid using glycerol-water mixtures with viscosities ranging from 4 to 280 cSt and with inlet pressures ranging from 3.5 to 10.5 kPa at gap spacings of 50-100 ?m. We estimate that the system produces residual film thicknesses in the range of 5-95 ?m. PMID:21599304

  1. Functionalization of Zr-based MOFs with alkyl and perfluoroalkyl groups: the effect on the water sorption behavior.

    Science.gov (United States)

    Yu, C; Bourrelly, S; Martineau, C; Saidi, F; Bloch, E; Lavrard, H; Taulelle, F; Horcajada, P; Serre, C; Llewellyn, P L; Magnier, E; Devic, T

    2015-12-01

    Stability and sorption of Metal-Organic Frameworks (MOFs) towards water are critical in many applications, and can a priori be modulated through the introduction of suitable organic functional groups on their backbone. We report here the preparation of a series of Zr(iv)-based MOFs functionalized with alkyl and perfluoroalkyl groups and their characterization by X-ray powder diffraction, multi-nuclei ((1)H, (13)C, (19)F) solid state nuclear magnetic resonance analyses, and nitrogen sorption measurements at 77 K. Their water sorption behavior was evaluated at 298 K and related to their physico-chemical features, highlighting both the effect of the confinement and the nature of the functional groups on the hydrophilic/hydrophobic balance. PMID:26473182

  2. Wettability Control on Fluid-Fluid Displacements in Patterned Microfluidics

    Science.gov (United States)

    Zhao, B.; Trojer, M.; Cueto-Felgueroso, L.; Juanes, R.

    2014-12-01

    Two-phase flow in porous media is important in many natural and industrial processes like geologic CO2 sequestration, enhanced oil recovery, and water infiltration in soil. While it is well known that the wetting properties of porous media can vary drastically depending on the type of media and the pore fluids, the effect of wettability on fluid displacement continues to challenge our microscopic and macroscopic descriptions. Here we study this problem experimentally, starting with the classic experiment of two-phase flow in a capillary tube. We image the shape of the meniscus and measure the associated capillary pressure for a wide range of capillary numbers. We confirm that wettability exerts a fundamental control on meniscus deformation, and synthesize new observations on the dependence of the dynamic capillary pressure on wetting properties (contact angle) and flow conditions (viscosity contrast and capillary number). We compare our experiments to a macroscopic phase-field model of two-phase flow. We use the insights gained from the capillary tube experiments to explore the viscous fingering instability in the Hele-Shaw geometry in the partial-wetting regime. A key difference between a Hele-Shaw cell and a porous medium is the existence of micro-structures (i.e. pores and pore throats). To investigate how these micro-structrues impact fluid-fluid displacement, we conduct experiments on a planar microfluidic device patterned with vertical posts. We track the evolution of the fluid-fluid interface and elucidate the impact of wetting on the cooperative nature of fluid displacement during pore invasion events. We use the insights gained from the capillary tube and patterned microfluidics experiments to elucidate the effect of wetting properties on viscous fingering and capillary fingering in a Hele-Shaw cell filled with glass beads, where we observe a contact-angle-dependent stabilizing behavior for the emerging flow instabilities, as the system transitions from drainage to imbibition.

  3. Reproductive Health Education and Services Needs of Internally Displaced Persons and Refugees following Disaster

    Science.gov (United States)

    Westhoff, Wayne W.; Lopez, Guillermo E.; Zapata, Lauren B.; Wilke Corvin, Jaime A.; Allen, Peter; McDermott, Robert J.

    2008-01-01

    Background: Following the occurrence of natural or man-made disaster, relief worker priorities include providing water, food, shelter, and immunizations for displaced persons. Like these essential initiatives, reproductive health education and services must also be incorporated into recovery efforts. Purpose: This study examined reproductive…

  4. Water structure as a function of temperature from X-ray scatteringexperiments and ab initio molecular dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Hura, Greg; Russo, Daniela; Glaeser, Robert M.; Head-Gordon,Teresa; Krack, Matthias; Parrinello, Michele

    2003-03-01

    We present high-quality X-ray scattering experiments on pure water taken over a temperature range of 2 to 77 C using a synchrotron beam line at the advanced light source (ALS) at Lawrence Berkeley National Laboratory. The ALS X-ray scattering intensities are qualitatively different in trend of maximum intensity over this temperature range compared to older X-ray experiments. While the common procedure is to report both the intensity curve and radial distribution function(s), the proper extraction of the real-space pair correlation functions from the experimental scattering is very difficult due to uncertainty introduced in the experimental corrections, the proper weighting of OO, OH, and HH contributions, and numerical problems of Fourier transforming truncated data in Q-space. Instead, we consider the direct calculation of X-ray scattering spectra using electron densities derived from density functional theory based on real-space configurations generated with classical water models. The simulation of the experimental intensity is therefore definitive for determining radial distribution functions over a smaller Q-range. We find that the TIP4P, TIP5P and polarizable TIP4P-Pol2 water models, with DFT-LDA densities, show very good agreement with the experimental intensities, and TIP4P-Pol2 in particular shows quantitative agreement over the full temperature range. The resulting radial distribution functions from TIP4P-Pol2 provide the current best benchmarks for real-space water structure over the biologically relevant temperature range studied here.

  5. Three-dimensional rigid body line displacement and 3D rigid body angle displacement measurements

    Science.gov (United States)

    Zhou, Jian; Zhao, Hong; Chen, Wenyi; Tian, Feng; Tan, Yushan

    1996-10-01

    Two new and simple methods for measuring the 3D rigid body line displacements and 3D rigid body angle displacements are proposed. And at the same time, two laser diodes and two new CMOS image sensors are used as light sources and photodetectors, respectively. Moreover, the experimental results are presented, which demonstrate the new methods have high accuracy, high processing speed, high reliability, and are easily realized.

  6. An alternative system for measuring displacements in bridges by using displacement transducers

    OpenAIRE

    Sena-Cruz, José; Garzón Roca, Julio; Escusa, Gonçalo Gomes; Carvalho, João

    2015-01-01

    One of the most important controlling parameters in bridges are the vertical displacements. Measuring deflections is not only valuable at the early stages of the construction, but during the service lifetime of the structure also. Furthermore, vertical displacements are one of the most important indicators of the healthy state of the bridges among other structural health monitoring parameters used in the assessment of the structural response of the bridges and for foreseeing eventual damage o...

  7. Voltage Gated Ion Channel Function: Gating, Conduction, and the Role of Water and Protons

    Directory of Open Access Journals (Sweden)

    Alisher M. Kariev

    2012-02-01

    Full Text Available Ion channels, which are found in every biological cell, regulate the concentration of electrolytes, and are responsible for multiple biological functions, including in particular the propagation of nerve impulses. The channels with the latter function are gated (opened by a voltage signal, which allows Na+ into the cell and K+ out. These channels have several positively charged amino acids on a transmembrane domain of their voltage sensor, and it is generally considered, based primarily on two lines of experimental evidence, that these charges move with respect to the membrane to open the channel. At least three forms of motion, with greatly differing extents and mechanisms of motion, have been proposed. There is a “gating current”, a capacitative current preceding the channel opening, that corresponds to several charges (for one class of channel typically 12–13 crossing the membrane field, which may not require protein physically crossing a large fraction of the membrane. The coupling to the opening of the channel would in these models depend on the motion. The conduction itself is usually assumed to require the “gate” of the channel to be pulled apart to allow ions to enter as a section of the protein partially crosses the membrane, and a selectivity filter at the opposite end of the channel determines the ion which is allowed to pass through. We will here primarily consider K+ channels, although Na+ channels are similar. We propose that the mechanism of gating differs from that which is generally accepted, in that the positively charged residues need not move (there may be some motion, but not as gating current. Instead, protons may constitute the gating current, causing the gate to open; opening consists of only increasing the diameter at the gate from approximately 6 Å to approximately 12 Å. We propose in addition that the gate oscillates rather than simply opens, and the ion experiences a barrier to its motion across the channel that is tuned by the water present within the channel. Our own quantum calculations as well as numerous experiments of others are interpreted in terms of this hypothesis. It is also shown that the evidence that supports the motion of the sensor as the gating current can also be consistent with the hypothesis we present.

  8. Switching the Biointerface of Displaceable Poly-p-xylylene Coatings.

    Science.gov (United States)

    Guan, Zhen-Yu; Wu, Chih-Yu; Li, Yi-Jye; Chen, Hsien-Yeh

    2015-07-01

    A new class of functionalized poly-p-xylyene coating has been synthesized to provide switchable and displaceable surface properties for biomaterials. The switchability is achieved through a mechanism for detaching/attaching biomolecules and/or a mechanism through which the programmed restoration of functions or their replacement by other functions can be carried out. This advanced version of poly-p-xylylene comprises an integrated disulfide moiety within the functional side group, and the switching phenomenon between the immobilized functional molecules is triggered by the redox thiol-disulfide interchange reaction. These dynamically well-defined molecules on the surfaces respond simultaneously to altered biological properties and controlled biointerfacial functions, for example, switching wettability or reversibly altered cell adhesion activity. Poly-p-xylylenes are a key player in controlling surface properties for many important applications, such as medical implants, biosensors, bioMEMS devices, and microfluidics. The introduction of this new facet of poly-p-xylylenes enables the dynamic mimicry of biological functions relevant to the design of new biomaterials. PMID:26084053

  9. Study of fast neutron scattering. The displacement cross-section (1962)

    International Nuclear Information System (INIS)

    We propose a method for calculating the biological efficiency of fast neutrons emitted by in-pile fission sources. This method justifies the empirical theory of Albert and Welton. In making simple assumptions concerning the cross-sections, we have supposed that the propagation can ben reduced to a mono-kinetic problem. A system of orthonormal functions is then set up making it possible to calculate the flux leaving a planar source. This method generalises the results obtained by Platzek to the case where the elastic cross-sections are not isotropic, and make it possible in particular to define a displacement cross-section: extension of the diffusion coefficient. This method can be generalised to the case of neutron diffraction as a function of time, and to the study of slowing-down. Numerical results are given in an appendix for the following: H2O, D2O, Fe, Be, Pb, CH, CH2. These cross-sections have been verified experimentally in water and in graphite for neutrons of 2.5 and 14 MeV using a SAMES accelerator and a 2 MeV Van De Graaff. (author)

  10. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    OpenAIRE

    J. Moeys; Larsbo, M.; Bergström, L; Brown, C.D.; Y. Coquet; Jarvis, N.J.

    2012-01-01

    Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisation usually rely on a set of lookup tables and (pedo)transfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which account...

  11. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    OpenAIRE

    J. Moeys; Larsbo, M.; Bergström, L; Brown, C.D.; Y. Coquet; Jarvis, N.J.

    2012-01-01

    Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisations usually rely on a set of lookup tables and (pedo)transfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accoun...

  12. An advanced CFD model to study the effect of non-condensable gas on cavitation in positive displacement pumps

    Science.gov (United States)

    Iannetti, Aldo; Stickland, Matthew T.; Dempster, William M.

    2015-09-01

    An advanced transient CFD model of a positive displacement reciprocating pump was created to study its behavior and performance in cavitating condition during the inlet stroke. The "full" cavitation model developed by Singhal et al. was utilized, and a sensitivity analysis test on two air mass fraction amounts (1.5 and 15 parts per million) was carried out to study the influence of the dissolved air content in water on the cavitation phenomenon. The model was equipped with user defined functions to introduce the liquid compressibility, which stabilizes the simulation, and to handle the two-way coupling between the pressure field and the inlet valve lift history. Estimation of the performance is also presented in both cases.

  13. Wirelessly Interrogated Position or Displacement Sensors

    Science.gov (United States)

    Woodard, Stanley E.; Taylor, Bryant D.

    2007-01-01

    Two simple position or displacement sensors based on inductance-capacitance resonant circuits have been conceived. These sensors are both powered and interrogated without use of wires and without making contact with other objects. Instead, excitation and interrogation are accomplished by means of a magnetic-field-response recorder. Both of the present position or displacement sensors consist essentially of variable rectangular parallel-plate capacitors electrically connected in series with fixed inductors. Simple inductance-capacitance circuits of the type used in these sensors are inherently robust; their basic mode of operation does not depend on maintenance of specific environmental conditions. Hence, these sensors can be used under such harsh conditions as cryogenic temperatures, high pressures, and radioactivity.

  14. MYTHIC DISPLACEMENT IN NIGERIAN NARRATIVES: AN INTRODUCTION

    Scientific Electronic Library Online (English)

    Ignatius, Chukwumah.

    2013-12-01

    Full Text Available Five decades of resorting to humanistic critical procedures have bequeathed to the Nigerian critical practice the legacy of examining and discovering in Nigerian and African narratives the historical and social concepts of the time and times they are presumed to posit. These concepts include colonia [...] lism, corruption, war, political instability, and culture conflict. These procedures are undertaken without due regard to seeing the whole of the literary tradition as a stream out of which narratives emerge. This article, therefore, by way of introduction, seeks to retrieve Nigerian narratives from "every author" and humanistic critical approach by placing them in a realm where a holistic method such as Frye's could be applied. Here, the traverses of the structure of mythical imagery such as the mythos of crime and punishment as embodied in these narratives and how this structure was displaced/shrouded from Frye's first mimetic mode to the last, via the concept of mythic displacement, will be analysed.

  15. Selective spectral displacement projection for multifrequency MRE

    International Nuclear Information System (INIS)

    We introduce a new motion encoding concept for the displacement vector in multifrequency magnetic resonance elastography (MRE). Selective spectral displacement projection (SDP)-MRE can be applied to a vibration spectrum composed of three frequencies and exploits the filter condition of MRE for selecting one frequency each per spatial motion encoding direction. The selected components are simultaneously encoded in the phase of the MR signal. Therefore, the total MR phase is represented by a sum of phase portions, each corresponding to a distinct spatial projection and vibration frequency. The individual components can be obtained by applying a Fourier-transform to the temporally resolved phase images. SDP-MRE reduces the number of temporally resolved MRE experiments for data acquisition by a factor of 3, while providing similar wave images as found using conventional monofrequency MRE. (paper)

  16. Energy simulation of displacement ventilation in offices

    Energy Technology Data Exchange (ETDEWEB)

    Hensen, J.L.M. [Strathclyde Univ., Glasgow (United Kingdom). Energy Systems Research Unit; Hamelinck, M.J.H. [Cauberg Huygen BV, Rotterdam (Netherlands)

    1995-09-01

    Modelling and simulation of heating, ventilating, and air-conditioning systems in the context of building performance evaluation is rapidly gaining more and more interest. The objective of the case study described in this paper is to evaluate the performance of displacement systems in offices (i.e. an environment with a low air pollution load) in terms of thermal energy. The paper describes the modelling, how the model is verified, and summarises the simulation results. The main conclusion of this case study is that - from an thermal energy point of view - application of a displacement system in typical offices is only recommended when the casual gains are relatively low (i.e. up to 30 W m{sup -2}). (author)

  17. Functioning of a Shallow-Water Sediment System during Experimental Warming and Nutrient Enrichment

    OpenAIRE

    Alsterberg, Christian; Sundbäck, Kristina; Hulth, Stefan

    2012-01-01

    Effects of warming and nutrient enrichment on intact unvegetated shallow-water sediment were investigated for 5 weeks in the autumn under simulated natural field conditions, with a main focus on trophic state and benthic nitrogen cycling. In a flow-through system, sediment was exposed to either seawater at ambient temperature or seawater heated 4°C above ambient, with either natural or nutrient enriched water. Sediment–water fluxes of oxygen and inorganic nutrients, nitrogen mineralization, a...

  18. Functional interactions in bacteriorhodopsin: a theoretical analysis of retinal hydrogen bonding with water.

    OpenAIRE

    Nina, M; Roux, B; Smith, J. C.

    1995-01-01

    The light-driven proton pump, bacteriorhodopsin (bR) contains a retinal molecule with a Schiff base moiety that can participate in hydrogen-bonding interactions in an internal, water-containing channel. Here we combine quantum chemistry and molecular mechanics techniques to determine the geometries and energetics of retinal Schiff base-water interactions. Ab initio molecular orbital calculations are used to determine potential surfaces for water-Schiff base hydrogen-bonding and to characteriz...

  19. Comparison of Pattern Recognition, Artificial Neural Network and Pedotransfer Functions for Estimation of Soil Water Parameters

    OpenAIRE

    Nasrin GORBANZADEH; Mohammad BANNAYAN AVAL; Amir LAKZIAN

    2010-01-01

    This paper presents the comparison of three different approaches to estimate soil water content at defined values of soil water potential based on selected parameters of soil solid phase. Forty different sampling locations in northeast of Iran were selected and undisturbed samples were taken to measure the water content at field capacity (FC), -33 kPa, and permanent wilting point (PWP), -1500 kPa. At each location solid particle of each sample including the percentage of sand, silt and clay w...

  20. Functional, histological and biomechanical characterization of wheat water-mutant leaves.

    Science.gov (United States)

    Rascio, Agata; Rascio, Nicoletta; Rinaldi, Michele; Valentini, Massimiliano

    2015-06-01

    A wheat (Triticum turgidum subsp. durum) mutant, generated with sodium azide from wild-type (WT) cv. 'Trinakria', differs in its water affinity of dry leaves, and was designated as a water-mutant. Compared with the WT, water-mutant leaves have lower rates of water uptake, while stomatal and cuticular transpiration do not differ. The nuclear magnetic resonance proton signals used for image reconstruction of leaf cross sections showed differences between these genotypes for the T1 proton spin-density and the T2 proton spin-spin relaxation time. Structural and histochemical analyses at midrib level showed that the water-mutant has thinner leaves, with more and smaller cells per unit area of mesophyll and sclerenchyma, and has altered staining patterns of lignin and pectin-like substances. Stress-strain curves to examine the rheological properties of the leaves showed a biphasic trend, which reveals that the tensile strength at break load and the elastic modulus of the second phase of the water-mutant are significantly higher than for the WT. These data support the proposal of interrelationships among local biophysical properties of the leaf, the microscopic water structure, the rheological properties and the water flux rate across the leaf. This water-mutant can be used for analysis of the genetic basis of these differences, and for identification of gene(s) that govern these traits. PMID:25212239

  1. Planar Displacement Detection with Point Feature Matching

    OpenAIRE

    Chen Feng-Dong; Hong Bing-Rong; Liu Guo-Dong

    2009-01-01

    A novel planar displacement detection method is implemented using Scale Invariant Feature Transform (SIFT) point feature matching on a calibrated optical grating-vision measuring platform. SIFT is a method for extracting and describing image key-points, which are robustly invariant to scale, rotation and translation as well as robust to illumination changes and limited changes of viewpoint. The platform is moved along its x axis step by step and a series of images are captured with correspond...

  2. Displacement Phenomena in Lectin Affinity Chromatography.

    Science.gov (United States)

    Cho, Wonryeon

    2015-10-01

    The work described here examines displacement phenomena that play a role in lectin affinity chromatography and their potential to impact reproducibility. This was achieved using Lycopersicon esculentum lectin (LEL), a lectin widely used in monitoring cancer. Four small identical LEL columns were coupled in series to form a single affinity chromatography system with the last in the series connected to an absorbance detector. The serial affinity column set (SACS) was then loaded with human plasma proteins. At the completion of loading, the column set was disassembled, the four columns were eluted individually, the captured proteins were trypsin digested, the peptides were deglycosylated with PNGase F, and the parent proteins were identified through mass spectral analyses. Significantly different sets of glycoproteins were selected by each column, some proteins appearing to be exclusively bound to the first column while others were bound further along in the series. Clearly, sample displacement chromatography (SDC) occurs. Glycoproteins were bound at different places in the column train, identifying the presence of glycoforms with different affinity on a single glycoprotein. It is not possible to see these phenomena in the single column mode of chromatography. Moreover, low abundance proteins were enriched, which facilitates detection. The great advantage of this method is that it differentiates between glycoproteins on the basis of their binding affinity. Displacement phenomena are concluded to be a significant component of the separation mechanism in heavily loaded lectin affinity chromatography columns. This further suggests that care must be exercised in sample loading of lectin columns to prevent analyte displacement with nonretained proteins. PMID:26348026

  3. International Monetary Fund and aid displacement.

    Science.gov (United States)

    Stuckler, David; Basu, Sanjay; McKee, Martin

    2011-01-01

    Several recent papers find evidence that global health aid is being diverted to reserves, education, military, or other sectors, and is displacing government spending. This is suggested to occur because ministers of finance have competing, possibly corrupt, priorities and deprive the health sector of resources. Studies have found that development assistance for health routed to governments has a negative impact on health spending and that similar assistance routed to private nongovernmental organizations has a positive impact. An alternative hypothesis is that World Bank and IMF macro-economic policies, which specifically advise governments to divert aid to reserves to cope with aid volatility and keep government spending low, could be causing the displacement of health aid. This article evaluates whether aid displacement was greater when countries undertook a new borrowing program from the IMF between 1996 and 2006. As found in existing studies, for each $1 of development assistance for health, about $0.37 is added to the health system. However, evaluating IMF-borrowing versus non-IMF-borrowing countries reveals that non-borrowers add about $0.45 whereas borrowers add less than $0.01 to the health system. On average, health system spending grew at about half the speed when countries were exposed to the IMF than when they were not. It is important to take account of the political economy of global health finance when interpreting data on financial flows. PMID:21319721

  4. The Theme of Displacement in Contemporary Art

    Directory of Open Access Journals (Sweden)

    John POTTS

    2012-03-01

    Full Text Available Cet article examine les images et idées de dislocation dans des œuvres d'art récentes. Le thème du déplacement ou de la dislocation est traité dans le contexte de l'aspect globalisant de l'art contemporain, considéré lui-même comme un reflet de la mondialisation. Les principaux textes théoriques qui influencent et informent les pratiques en matière de conservation sont abordés, entre autres les écrits de Giorgio Agamben, Nicolas Bourriaud et Rex Butler. Le thème de la dislocation dans l'art contemporain est analysé au travers des œuvres de nombreux artistes, tels que Francis Alÿs, Bill Fontana, Allan Sekula, Chen Chieh-jen, Ai Wei Wei, Rosemary Laing, Mike Parr, Santiago Sierra, Rebecca Belmore et Tracey Moffatt.This essay considers images and ideas of displacement in recent works of art. The theme of displacement is examined in the context of the globalist aspect of contemporary art, itself a reflection of globalisation. Influential theoretical texts informing curatorial practice and the discourse of contemporary art theory are discussed, including the writings of Girogio Agamben, Nicolas Bourriaud and Rex Butler. The theme of displacement in contemporary art is analysed with regard to the work of many artists, including Francis Alÿs, Bill Fontana, Allan Sekula, Chen Chieh-jen, Ai Wei Wei, Rosemary Laing, Mike Parr, Santiago Sierra, Rebecca Belmore and Tracey Moffatt.

  5. Holding Water in the Landscape; striking a balance between food production and healthy catchment function

    Science.gov (United States)

    Quinn, Paul; Wilkinson, Mark; Stutter, Marc; Adams, Russell

    2015-04-01

    Here it is proposed that ~5 % of the rural landscape could be modified to hold water during storm events. Hence ~95% of land remains for food production, commercial forestry and amenity. This is a catchment scale commitment to sustainably reducing flood and drought risk, improving water quality, biodiversity and thereby climate proofing our catchments. The farmed landscape has intensified and as a result, runoff rates are no longer in balance with the catchment needs, which in turn contributes to floods, droughts and water pollution problems. The loss of infiltration rates, soil water holding capacity and the increase in ditches and drains through intense farming has resulted in a reduction of the overall water holding capacity of the landscape, therefore deeper soil and aquifer recharge rates are lower. However, adequate raw water supply and food production is also vital. Here we consider how ~5% of productive land could be used to physically hold water during and after storms. This is a simple philosophy for water stewardship that could be delivered by farmers and land managers themselves. In this poster we consider a 'treatment train' of mitigation in headwaters by the construction of:- Rural SuDs - by creating swales, bunds and grassy filters; Buffer Strips - (designed to hold water); The Ditch of The Future - by creating the prime location for holding water and recovering lost top soil and finally the better use of Small Headwater Floodplains - by storing flood water, creating wetlands, planting new forest, installing woody debris and new habitats. We present examples of where and how these measures have been installed and show the cost-effectiveness of temporarily holding storm runoff in several case study catchments taken from the UK.

  6. 10-Day survival of Hyalella azteca as a function of water quality parameters.

    Science.gov (United States)

    Javidmehr, Alireza; Kass, Philip H; Deanovic, Linda A; Connon, Richard E; Werner, Inge

    2015-05-01

    Estuarine systems are among the most impacted ecosystems due to anthropogenic contaminants; however, they present unique challenges to toxicity testing with regard to varying water quality parameters. The euryhaline amphipod species, Hyalella azteca, is widely used in toxicity testing and well suited for testing estuarine water samples. Nevertheless, the influence of relevant water quality parameters on test endpoints must be quantified in order to efficiently use this species for routine monitoring. Here, we studied the influence of five water quality parameters: electrical conductivity, pH, un-ionized ammonia, dissolved oxygen and temperature, on H. azteca survival in a water column toxicity test. A model was developed to quantify and predict the independent and interacting effects of water quality variables on 10-day survival. The model allows simultaneous assessment of multiple potential predictors recorded during the tests. Data used for modeling came from 1089 tests performed on ambient water samples over a period of three years (2006-2008). The final model reflects significant effects of predictors and their two-way interactions. The effect of each level of all predictors on survival probability of H. azteca was examined by comparing levels of each predictor at a time, while holding all others at their lowest (reference) level. This study showed that predictors of survival in water column tests should not be evaluated in isolation in the interpretation of H. azteca water column tests. Our model provides a useful tool to predict expected control survival based on relevant water quality parameters, and thus enables the use of H. azteca tests for toxicity monitoring in estuaries with a wide range of water quality conditions. PMID:25725458

  7. Estimation of the Uplift Displacement of a Sewage Manhole in Liquefied Ground

    International Nuclear Information System (INIS)

    A simplified method to estimate the maximum uplift displacement of a manhole and settlements of backfill soil under liquefaction is proposed. The method is derived based on the mechanism of uplifting of a manhole under undrained condition of backfill soil. It also has a capability of estimating effectiveness of countermeasures against uplifting by considering excess pore water pressure ratio and/or unit weight of backfill soil. In the present study, however, estimation for the case of no countermeasure is verified through comparison with experimental results. Results show that measured uplift displacements and settlements are confined within the boundary predicted by the proposed method

  8. Airflow and Contaminant Distribution in Hospital Wards with a Displacement Ventililation System

    DEFF Research Database (Denmark)

    Qian, H.; Nielsen, Peter Vilhelm

    2004-01-01

    Airflow and Contaminant Distribution in Hospital Wards with a Displacement Ventilalation System. The 2nd International Conference on Build Environment and Public Health, BEPH 2004, Shenzhen , China . ABSTRACT Displacement ventilation has not been considered to be an applicable system for hospital wards probably due to its inability to remove large particles and risk of particle deposition on horizontal surfaces in the occupied regions. However, the existing downward ventilation system commonly used in isolation rooms does not deliver the required performance. There is a need to develop effective ventilation system in hospital wards. It is for this purpose that we study the performance of displacement ventilation in hospital wards as one of the steps to optimize the ventilation design. When the prospect of applying displacement ventilation system in a hospital ward is examined, it should be necessary to accurately predict three-dimensional distribution of air velocity, temperature, and contaminant concentration in the ward. Indoor airflow in a displacement ventilation system involves a combination of different flow streams such as the gravity currents and thermal plumes. It is important to choose an appropriate turbulent model to simulate and reproduce the process of contaminant dispersion. The low Reynolds-number (LRN) k-e (Launder and Sharma, 1978) turbulence model with a damping function (Chikamoto et al., 1992) was considered and evaluated by experiment. We carried out an experimental study to test the performance of the displacement ventilation system in a hospital ward. The results of LRN k-e model with damping function agreed well with the measured data. Furthermore, the flow pattern showed by the calculated age of air agreed well with observed flow pattern by smoke visualization. The CFD results assisted us to understand the contaminant dispersion. It was shown that the interaction of exhaled flow and the body thermal plume generated by manikin would affect exhaled virus-laden aerosols distribution in the ward with displacement ventilation system.

  9. Density functional theory meta-GGA + U study of water incorporation in the metal-organic framework material Cu-BTC

    Science.gov (United States)

    Cockayne, Eric; Nelson, Eric B.

    2015-07-01

    Water absorption in the metal-organic framework (MOF) material Cu-BTC, up to a concentration of 3.5 H2O per Cu ion, is studied via density functional theory at the meta-GGA + U level. The stable arrangements of water molecules show chains of hydrogen-bonded water molecules and a tendency to form closed cages at high concentration. Water clusters are stabilized primarily by a combination of water-water hydrogen bonding and Cu-water oxygen interactions. Stability is further enhanced by van der Waals interactions, electric field enhancement of water-water bonding, and hydrogen bonding of water to framework oxygens. We hypothesize that the tendency to form such stable clusters explains the particularly strong affinity of water to Cu-BTC and related MOFs with exposed metal sites.

  10. The presence of water influences reproductive function in the song sparrow (Melospiza melodia morphna).

    Science.gov (United States)

    Wingfield, John C; Sullivan, Kimberley; Jaxion-Harm, Jessica; Meddle, Simone L

    2012-09-15

    Cumulative evidence indicates that song sparrows, Melospiza melodia morphna, of western Washington State prefer territories close to water. Densities of territories were higher within 50 m of open water and analysis of stomach contents revealed aquatic organisms. An unusually dry period (less open water) in May and June 1997 had no effect on latency of territorial males to respond to a simulated territorial intrusion (STI), but the number of songs and closest approach to the decoy were lower than those recorded in June 1988 (no major dry periods). A laboratory experiment was conducted in which males and females were exposed to long days to stimulate reproductive development. One group received a bath with water daily and the other group received a dry bath (both groups had ad libitum access to drinking water through a glass tube). Birds with a dry bath tended to show reduced photoperiodically-induced gonadal growth compared with birds that had access to water in the bath. Plasma levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) increased following photostimulation in all groups. However, LH levels were higher in females with access to water. There were no differences in hormone levels in any of the other groups. Taken together these novel data indicate that presence and access to open water could be an important environmental cue for song sparrows in western Washington State. Implications for global climate change and droughts are suggested. PMID:22809668

  11. Soil surfactant products for improving hydrologic function in post-fire water repellent soil

    Science.gov (United States)

    There are a wide range of soil surfactant chemistries on the market today that are primarily designed for the treatment of water repellent soils in cropping and turfgrass systems. These chemicals may also have potential in treating the deleterious effects associated with post-fire water repellent so...

  12. 24 CFR 886.138 - Displacement, relocation, and acquisition.

    Science.gov (United States)

    2010-04-01

    ...maintain data on the race, ethnic, gender, and handicap status of displaced persons. (g) Definition of displaced person. (1) for purposes...be covered by this section. (h) Definition of initiation of negotiations....

  13. 24 CFR 236.1001 - Displacement, relocation, and acquisition.

    Science.gov (United States)

    2010-04-01

    ...maintain data on the race, ethnic, gender, and disability status of displaced persons. (g) Definition of displaced person. (1) For purposes...be covered by this section. (h) Definition of initiation of negotiations....

  14. 24 CFR 941.207 - Displacement, relocation, and acquisition.

    Science.gov (United States)

    2010-04-01

    ...including data indicating the race, ethnic, gender and disability status of displaced persons. (h) Definition of displaced person. (1) For purposes...be covered by this section. (i) Definition of initiation of negotiations. For...

  15. 24 CFR 886.338 - Displacement, relocation, and acquisition.

    Science.gov (United States)

    2010-04-01

    ...maintain data on the race, ethnic, gender, and handicap status of displaced persons. (g) Definition of displaced person. (1) For purposes...be covered by this section. (h) Definition of initiation of negotiations....

  16. 24 CFR 882.810 - Displacement, relocation, and acquisition.

    Science.gov (United States)

    2010-04-01

    ...maintain data on the racial, ethnic, gender, and disability status of displaced persons. (g) Definition of displaced person. (1) For purposes...be covered by this section. (h) Definition of initiation of negotiations....

  17. Translational diffusion of hydration water correlates with functional motions in folded and intrinsically disordered proteins

    Science.gov (United States)

    Schirò, Giorgio; Fichou, Yann; Gallat, Francois-Xavier; Wood, Kathleen; Gabel, Frank; Moulin, Martine; Härtlein, Michael; Heyden, Matthias; Colletier, Jacques-Philippe; Orecchini, Andrea; Paciaroni, Alessandro; Wuttke, Joachim; Tobias, Douglas J.; Weik, Martin

    2015-03-01

    Hydration water is the natural matrix of biological macromolecules and is essential for their activity in cells. The coupling between water and protein dynamics has been intensively studied, yet it remains controversial. Here we combine protein perdeuteration, neutron scattering and molecular dynamics simulations to explore the nature of hydration water motions at temperatures between 200 and 300?K, across the so-called protein dynamical transition, in the intrinsically disordered human protein tau and the globular maltose binding protein. Quasi-elastic broadening is fitted with a model of translating, rotating and immobile water molecules. In both experiment and simulation, the translational component markedly increases at the protein dynamical transition (around 240?K), regardless of whether the protein is intrinsically disordered or folded. Thus, we generalize the notion that the translational diffusion of water molecules on a protein surface promotes the large-amplitude motions of proteins that are required for their biological activity.

  18. On switching H? controllers for nuclear steam generator water level: A multiple parameter-dependent Lyapunov functions approach

    International Nuclear Information System (INIS)

    Poor control of the steam generator (SG) water level in the secondary circuit of a nuclear power plant can lead to frequent reactor shutdowns. From the viewpoint of economic operation, it is critical to keep the water level of SG in well control. This paper presents a new framework for addressing this problem based on switching control to linear parameter varying (LPV) systems. A family of LPV controllers are designed, and each of them is suitable for a specific operating range. Under the admissible switching logic, the closed-loop system remains stable and achieves prescribed H? performance in the entire operating range. The approach is based on multiple parameter-dependent Lyapunov functions, which is less conservative than the employment of a single Lyapunov function. The switching LPV control scheme is then applied to the level control problem

  19. Displaced Workers. Overview: ERIC Fact Sheet No. 21.

    Science.gov (United States)

    Miller, Juliet

    The displaced worker is an individual who has been laid off from a job and has little or no hope of returning to that particular position. The number of displaced workers is large and is apt to increase. Displaced workers are typically male, older, not highly educated, and are union members with several years of seniority and above-average wages.…

  20. Year of displaced people’s rights in Colombia

    Directory of Open Access Journals (Sweden)

    Marco Alberto Romero

    2007-12-01

    Full Text Available A Campaign for the Rights of Displaced People in Colombia, launched in 2007 by UNHCR, Colombian NGO CODHES and the Catholic Church, has tried to raise awareness in Colombia and the international community about the severity of the country’s displacement crisis and its failure to guarantee the rights of displaced people.

  1. Bayesian Speckle Tracking. Part II: Biased Ultrasound Displacement Estimation

    OpenAIRE

    Byram, Brett; TRAHEY, GREGG E.; Palmeri, Mark

    2013-01-01

    Ultrasonic displacement estimates have numerous clinical uses including blood-flow, elastography, therapeutic guidance and ARFI imaging. These clinical tasks could be improved with better ultrasonic displacement estimates. Traditional ultrasonic displacement estimates are limited by the Cramer-Rao lower bound (CRLB). The CRLB can be surpassed using biased estimates. In this paper a framework for biased estimation using Bayes’ theorem is described.

  2. Year of displaced people’s rights in Colombia

    OpenAIRE

    Marco Alberto Romero

    2007-01-01

    A Campaign for the Rights of Displaced People in Colombia, launched in 2007 by UNHCR, Colombian NGO CODHES and the Catholic Church, has tried to raise awareness in Colombia and the international community about the severity of the country’s displacement crisis and its failure to guarantee the rights of displaced people.

  3. Enhanced electrocaloric effect in displacive-type organic ferroelectrics

    Science.gov (United States)

    Ding, L. J.; Zhong, Y.; Fan, S. W.; Zhu, L. Y.

    2015-08-01

    We explore the intrinsic feature of electrocaloric effect (ECE) accompanied by ferroelectric (FE)-paraelectric (PE) transition for displacive-type organic ferroelectrics using Green's function theory. It is demonstrated that decreasing elastic constant K or increasing spin-lattice coupling ? can enhance the ECE, as well as polarization P and transition temperature TC. Indeed, one expects that the optimal operating temperature for solid-state refrigeration is around room temperature, at which the ECE achieves its maximum. As TC is tuned to ˜310 K, it presents larger ECE response and remanent polarization with lower coercive field for smaller K value, suggesting that well flexible displacive-type organic ferroelectrics are excellent candidates both for electric cooling and data storage in the design of nonvolatile FE random-access memories. Furthermore, in an electric field, it provides a bridge between a Widom line that denotes FE-PE crossover above TC and a metaelectric transition line below TC that demonstrates an FE switching behavior with an antiparallel field.

  4. Beyond the hydrophobic effect: Critical function of water at biological phase boundaries--A hypothesis.

    Science.gov (United States)

    Damodaran, Srinivasan

    2015-07-01

    Many life-sustaining processes in living cells occur at the membrane-water interface. The pertinent questions that need to be asked are what is the evolutionary reason for biology to choose the membrane-water interface as the site for performing and/or controlling crucial biological reactions and what is the key physical principle that is singular to the membrane-water interface that biology exploits for regulating metabolic processes in cells? In this review, a hypothesis is developed, which espouses that cells control activities of membrane-bound enzymes and receptor activated processes via manipulating the thermodynamic activity of water at the membrane-water interfacial region. In support of this hypothesis, first we establish that the surface pressure of a lipid monolayer is a direct measure of a reduction in the thermodynamic activity of interfacial water. Second, we show that the surface pressure-dependent activation/inactivation of interfacial enzymes is fundamentally related to their dependence on interfacial water activity. We extend this argument to infer that cells might manipulate activities of membrane-associated biological processes via manipulating the activity of interfacial water via localized compression or expansion of the interface. In this paper, we critically analyze literature data on mechano-activation of large pore ion channels in Escherichia coli spheroplasts and G-proteins in reconstituted lipid vesicles, and show that these pressure-induced activation processes are fundamentally and quantitatively related to changes in the thermodynamic state of interfacial water, caused by mechanical stretching of the bilayer. PMID:25888225

  5. Amine functionalized radiation-induced grafted water hyacinth fibers for Pb2+, Cu2+ and Cr3+ uptake

    International Nuclear Information System (INIS)

    An amine group containing fibrous adsorbent was prepared by reaction of grafted water hyacinth fibers with ethylenediamine. Glycidyl methacrylate (GMA) was grafted onto water hyacinth fibers using gamma radiation induced graft polymerization through simultaneous grafting technique and this was used as base material for producing the amine type adsorbents. The conversion of the epoxy group from GMA into amine group was investigated. The concentration of ethylenediamine solution that gave the highest amine functional group density was 50% by volume in 2-propanol. The amine functionalized water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), and Energy Dispersive X-ray Spectroscopy (EDX). Information derived from these analyses confirms the successful conversion of the epoxy group. The amine-type adsorbent was evaluated for its uptake of Pb2+, Cu2+ and Cr3+ from aqueous solutions. The initial concentration of the metal ions and pH of the solutions were found to influence the amount of metal ions adsorbed by the amine-type adsorbent. The kinetics of adsorption was observed to follow Lagergren's first order equation. Results of ion sorption studies indicate that gamma radiation-induced grafting and subsequent chemical modification improved the ion sorption behaviour of water hyacinth fibers. - Highlights: • RIGP and amination imparted higher ion sorption capacity to water hyacinth fibers. • The epoxy group of grafted glycidyl methacrylate was reacted with ethylenediamine. • TGA, ATR-FTIR and EDX analysis confirmed successful amine functionalization. • The amine type fibrous adsorbent has higher affinity for Cu2+ and Pb2+ than Cr3+

  6. Transport Behavior of Functionalized Multi-Wall Carbon Nanotubes in Water-Saturated Quartz Sand as a Function of Tube Length

    OpenAIRE

    Wang, Yonggang; Kim, Jae-Hong; Baek, Jong-Beom; Gary W. Miller; Pennell, Kurt D.

    2012-01-01

    A series of one-dimensional column experiments was conducted to examine the effects of tube length on the transport and deposition of 4-ethoxybenzoic acid functionalized multi-wall carbon nanotubes (MWCNTs) in water-saturated porous media. Aqueous MWCNTs suspensions were prepared to yield three distributions of tube lengths; 0.02–1.3 ?m (short), 0.2–7.5 ?m (medium), and 0.2–21.4 ?m (long). Results of the column studies showed that MWCNT retention increased with increasing tube length. Neverth...

  7. The displacement estimation error back-propagation (DEEP) method for a multiple structural displacement monitoring system

    International Nuclear Information System (INIS)

    Visually servoed paired structured light system (ViSP) has been found to be useful in estimating 6-DOF relative displacement. The system is composed of two screens facing each other, each with one or two lasers, a 2-DOF manipulator and a camera. The displacement between two sides is estimated by observing positions of the projected laser beams and rotation angles of the manipulators. To apply the system to massive structures, the whole area should be partitioned and each ViSP module is placed in each partition in a cascaded manner. The estimated displacement between adjoining ViSPs is combined with the next partition so that the entire movement of the structure can be estimated. The multiple ViSPs, however, have a major problem that the error is propagated through the partitions. Therefore, a displacement estimation error back-propagation (DEEP) method which uses Newton–Raphson or gradient descent formulation inspired by the error back-propagation algorithm is proposed. In this method, the estimated displacement from the ViSP is updated using the error back-propagated from a fixed position. To validate the performance of the proposed method, various simulations and experiments have been performed. The results show that the proposed method significantly reduces the propagation error throughout the multiple modules. (paper)

  8. Hierarchic Theory of Condensed Matter Role of water in protein dynamics, function and cancer emergency

    CERN Document Server

    Kaivarainen, A

    2000-01-01

    1. Role of inter-domain water clusters in large-scale dynamics of proteins; 2. Description of large-scale dynamics of proteins based on generalized Stokes-Einstein and Eyring-Polany equation; 3. Dynamic model of protein-ligand complexes formation; 4. The life-time of quasiparticles and frequencies of their excitation; 5. Mesoscopic mechanism of enzyme catalysis; 6. The mechanism of ATP hydrolysis energy utilization in muscle contraction and protein polymerization; 7. Water activity as a regulative factor in the intra- and inter-cell processes; 8. Water and cancer.

  9. Light-induced water oxidation at silicon electrodes functionalized with a cobalt oxygen-evolving catalyst

    OpenAIRE

    Pijpers, Joep J. H.; Winkler, Mark T.; Surendranath, Yogesh; Buonassisi, Tonio; Nocera, Daniel G

    2011-01-01

    Integrating a silicon solar cell with a recently developed cobalt-based water-splitting catalyst (Co-Pi) yields a robust, monolithic, photo-assisted anode for the solar fuels process of water splitting to O2 at neutral pH. Deposition of the Co-Pi catalyst on the Indium Tin Oxide (ITO)-passivated p-side of a np-Si junction enables the majority of the voltage generated by the solar cell to be utilized for driving the water-splitting reaction. Operation under neutral pH conditions fosters enhanc...

  10. Handling Customers’ Objection as an Entrepreneurial Function: A Study of Sachet Water Industry in Cross River State, Nigeria

    OpenAIRE

    Felix John Eze; Ireneus Chukwudi Nwaizugbo

    2012-01-01

    The study evaluated the association between consumers’ objection and entrepreneurial function among selected entrepreneurs and customers of sachet water in Calabar, Cross River State, Nigeria. Specifically, the study hinges on determining the relationship between consumer’s objection and long term customer loyalty, the extent to which price objection affect entrepreneur’s profitability and whether entrepreneurs are responsive to price objection. The survey research design was used while Pears...

  11. Climate Change and Water Use Partitioning by Different Plant Functional Groups in a Grassland on the Tibetan Plateau

    OpenAIRE

    Hu, Jia; Hopping, Kelly A.; Bump, Joseph K; Kang, Sichang; Klein, Julia A.

    2013-01-01

    The Tibetan Plateau (TP) is predicted to experience increases in air temperature, increases in snowfall, and decreases in monsoon rains; however, there is currently a paucity of data that examine the ecological responses to such climate changes. In this study, we examined the effects of increased air temperature and snowfall on: 1) water use partitioning by different plant functional groups, and 2) ecosystem CO2 fluxes throughout the growing season. At the individual plant scale, we used stab...

  12. Hamiltonian fluid reductions of drift-kinetic equations and the correspondence with water-bag distribution functions

    CERN Document Server

    Perin, Maxime; Tassi, Emanuele

    2015-01-01

    Hamiltonian models for the first three moments of the drift-kinetic distribution function, namely the density, the fluid velocity and the parallel pressure, are derived from the Hamiltonian structure of the drift-kinetic equations. The link with the water-bag closure is established, showing that, unlike the one-dimensional Vlasov equations, these solutions are the only Hamiltonian fluid reductions for the drift-kinetic equation. These models are discussed through their equations of motion and their Casimir invariants.

  13. Assessing the accuracy of quantum Monte Carlo and density functional theory for energetics of small water clusters

    OpenAIRE

    Gillan, M. J.; Manby, F. R.; Towler, M. D.; Alfe?, D.

    2012-01-01

    We present a detailed study of the energetics of water clusters (H$_2$O)$_n$ with $n \\le 6$, comparing diffusion Monte Carlo (DMC) and approximate density functional theory (DFT) with well converged coupled-cluster benchmarks. We use the many-body decomposition of the total energy to classify the errors of DMC and DFT into 1-body, 2-body and beyond-2-body components. Using both equilibrium cluster configurations and thermal ensembles of configurations, we find DMC to be unif...

  14. [Safety systems in nuclear power plants with pressurized water reactors and demonstration of their function in technical scale experiments. II].

    Science.gov (United States)

    Hennies, H H

    1987-11-01

    Analyses and experiments carried out during the last decade on the sequence and consequences of accidents in German pressurized water reactors have shown that the functioning capability of the safety systems is guaranteed for the case of the MCA, the maximum credible accident. For the case of core meltdown, simulation experiments have also made it evident that the consequences remain largely restricted to the plant proper. PMID:3431585

  15. Density functional theory study of oxygen and water adsorption on SrTiO{sub 3}(001)

    Energy Technology Data Exchange (ETDEWEB)

    Guhl, Hannes

    2010-12-03

    Strontium titanate is an extensively studied material with a wide range of application, for instance in photo-catalysis and most importantly, it is used as a substrate in growth of functional oxides. The surface chemistry is crucial and hence understanding the surface structure on atomic scale is essential for gaining insight into the fundamental processes in the aforementioned applications. Moreover, there exist a lot of evidence that this surface chemistry might be controlled to considerably by extrinsic species, such as residual hydrogen and water. Investigating the properties of water and oxygen on the strontium titanate surface is certainly a natural starting point for a theoretical study based on density functional theory, because these species are practically present on the surface on a wide range of experimental conditions and they are computationally feasible. For the oxygen and water adsorption the binding energy is controlled by long-range surface relaxations leading to an effective repulsion of the adsorbed specimen. The isolated oxygen ad-atom forms a covalently bonded ''quasi-peroxide anion'' in combination with a lattice oxygen atom. Contrariwise, in all investigated configurations containing water molecules and hydroxyl groups, the respective oxygen atoms assumed positions close to the oxygen sites of the continued perovskite lattice of the substrate. Most remarkably, on the strontium oxide termination, the water molecules adsorbs and dissociates effortlessly leading to the formation of a pair of hydroxyl groups. For the titanium dioxide termination, a coverage dependent adsorption mode is observed. Densely packings stabilize water molecules, whereas at lower coverage and finite temperatures the formation of hydroxyl groups is found. The energetics responsible for this behavior is consistent with recent experiments by Iwahori and coworkers. (orig.)

  16. Density functional theory study of oxygen and water adsorption on SrTiO3(001)

    International Nuclear Information System (INIS)

    Strontium titanate is an extensively studied material with a wide range of application, for instance in photo-catalysis and most importantly, it is used as a substrate in growth of functional oxides. The surface chemistry is crucial and hence understanding the surface structure on atomic scale is essential for gaining insight into the fundamental processes in the aforementioned applications. Moreover, there exist a lot of evidence that this surface chemistry might be controlled to considerably by extrinsic species, such as residual hydrogen and water. Investigating the properties of water and oxygen on the strontium titanate surface is certainly a natural starting point for a theoretical study based on density functional theory, because these species are practically present on the surface on a wide range of experimental conditions and they are computationally feasible. For the oxygen and water adsorption the binding energy is controlled by long-range surface relaxations leading to an effective repulsion of the adsorbed specimen. The isolated oxygen ad-atom forms a covalently bonded ''quasi-peroxide anion'' in combination with a lattice oxygen atom. Contrariwise, in all investigated configurations containing water molecules and hydroxyl groups, the respective oxygen atoms assumed positions close to the oxygen sites of the continued perovskite lattice of the substrate. Most remarkably, on the strontium oxide termination, the water molecules adsorbs and dissociates effortlessly leading to the formation of a pair of hydroxyl groups. For the titanium dioxide termination, a coverage dependent adsorption mode is observed. Densely packings stabilize water molecules, whereas at lower coverage and finite temperatures the formation of hydroxyl groups is found. The energetics responsible for this behavior is consistent with recent experiments by Iwahori and coworkers. (orig.)

  17. Synergy of extreme drought and shrub invasion reduce ecosystem functioning and resilience in water-limited climates.

    Science.gov (United States)

    Caldeira, Maria C; Lecomte, Xavier; David, Teresa S; Pinto, Joaquim G; Bugalho, Miguel N; Werner, Christiane

    2015-01-01

    Extreme drought events and plant invasions are major drivers of global change that can critically affect ecosystem functioning and alter ecosystem-atmosphere exchange. Invaders are expanding worldwide and extreme drought events are projected to increase in frequency and intensity. However, very little is known on how these drivers may interact to affect the functioning and resilience of ecosystems to extreme events. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that native shrub invasion and extreme drought synergistically reduced ecosystem transpiration and the resilience of key-stone oak tree species. Ecosystem transpiration was dominated by the water use of the invasive shrub Cistus ladanifer, which further increased after the extreme drought event. Meanwhile, the transpiration of key-stone tree species decreased, indicating a competitive advantage in favour of the invader. Our results suggest that in Mediterranean-type climates the invasion of water spending species and projected recurrent extreme drought events may synergistically cause critical drought tolerance thresholds of key-stone tree species to be surpassed, corroborating observed higher tree mortality in the invaded ecosystems. Ultimately, this may shift seasonally water limited ecosystems into less desirable alternative states dominated by water spending invasive shrubs. PMID:26461978

  18. Synergy of extreme drought and shrub invasion reduce ecosystem functioning and resilience in water-limited climates

    Science.gov (United States)

    Caldeira, Maria C.; Lecomte, Xavier; David, Teresa S.; Pinto, Joaquim G.; Bugalho, Miguel N.; Werner, Christiane

    2015-10-01

    Extreme drought events and plant invasions are major drivers of global change that can critically affect ecosystem functioning and alter ecosystem-atmosphere exchange. Invaders are expanding worldwide and extreme drought events are projected to increase in frequency and intensity. However, very little is known on how these drivers may interact to affect the functioning and resilience of ecosystems to extreme events. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that native shrub invasion and extreme drought synergistically reduced ecosystem transpiration and the resilience of key-stone oak tree species. Ecosystem transpiration was dominated by the water use of the invasive shrub Cistus ladanifer, which further increased after the extreme drought event. Meanwhile, the transpiration of key-stone tree species decreased, indicating a competitive advantage in favour of the invader. Our results suggest that in Mediterranean-type climates the invasion of water spending species and projected recurrent extreme drought events may synergistically cause critical drought tolerance thresholds of key-stone tree species to be surpassed, corroborating observed higher tree mortality in the invaded ecosystems. Ultimately, this may shift seasonally water limited ecosystems into less desirable alternative states dominated by water spending invasive shrubs.

  19. Amine functionalized radiation-induced grafted water hyacinth fibers for Pb2+, Cu2+ and Cr3+ uptake

    Science.gov (United States)

    Madrid, Jordan F.; Nuesca, Guillermo M.; Abad, Lucille V.

    2014-04-01

    An amine group containing fibrous adsorbent was prepared by reaction of grafted water hyacinth fibers with ethylenediamine. Glycidyl methacrylate (GMA) was grafted onto water hyacinth fibers using gamma radiation induced graft polymerization through simultaneous grafting technique and this was used as base material for producing the amine type adsorbents. The conversion of the epoxy group from GMA into amine group was investigated. The concentration of ethylenediamine solution that gave the highest amine functional group density was 50% by volume in 2-propanol. The amine functionalized water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), and Energy Dispersive X-ray Spectroscopy (EDX). Information derived from these analyses confirms the successful conversion of the epoxy group. The amine-type adsorbent was evaluated for its uptake of Pb2+, Cu2+ and Cr3+ from aqueous solutions. The initial concentration of the metal ions and pH of the solutions were found to influence the amount of metal ions adsorbed by the amine-type adsorbent. The kinetics of adsorption was observed to follow Lagergren's first order equation. Results of ion sorption studies indicate that gamma radiation-induced grafting and subsequent chemical modification improved the ion sorption behaviour of water hyacinth fibers.

  20. Amine functionalized radiation-induced grafted water hyacinth fibers for Pb2+, Cu2+ and Cr3+ uptake

    International Nuclear Information System (INIS)

    An amine group containing fibrous adsorbent was prepared by reaction of grafted water hyacinth fibers with ethylenediamine. Glycidyl methacrylate (GMA) was grafted onto water hyacinth fibers using gamma radiation induced graft polymerization through simultaneous grafting technique and this was used as base material for producing the amine type adsorbents. The conversion of the epoxy group from GMA into amine group was investigated. The concentration of ethylenediamine solution that gave the highest amine functional group density was 50% by volume in 2-propanol. The amine functionalized water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), and Energy Dispersive X-ray Spectroscopy(EDX). Information derived from these analyses confirms the successful conversion of the epoxy group. The amine type adsorbent was evaluated for its uptake of Pb2+, Cu2+ and Cr3+ from aqueous solutions. The initial concentration of the metal ions and pH of the solutions were found to influence the amount of metal ions adsorbed by the amine-type adsorbent. The kinetics of adsorption was observed to follow Lagergen's first order equation. Results of ion sorption studies indicate that gamma radiation-induced grafting and subsequent chemical modification improved the ion sorption behaviour of water hyacinth fibers. (Author)

  1. Ortho-functionalized perylenediimides for highly fluorescent water-soluble dyes.

    Science.gov (United States)

    Battagliarin, Glauco; Davies, Melari; Mackowiak, Stephan; Li, Chen; Müllen, Klaus

    2012-03-01

    Clearly visible: A water-soluble and highly fluorescent perylenediimide is synthesized via ruthenium-catalyzed alkylation with outstanding yields. For the first time, the possibility to use phosphonate derivatives in a Murai-type reaction is demonstrated. PMID:22241589

  2. Operative versus nonoperative treatment of displaced midshaft clavicle fractures in adults : a systematic review

    DEFF Research Database (Denmark)

    Rehn, Carl-Henrik; Kirkegaard, Martin

    2013-01-01

    Intervention studies of clavicle fracture treatment are numerous, but only a few high quality studies prospectively compare operative and nonoperative treatment. The objective of this study was to review evidence from randomized controlled trials on operative versus nonoperative treatment of displaced midshaft clavicle fractures in adults with focus on fracture healing, complications and functional outcome.

  3. Four quadrant parallel peripheral screw fixation for displaced femoral neck fractures in elderly patients

    Directory of Open Access Journals (Sweden)

    Bhava RJ Satish

    2013-01-01

    Conclusion: Closed reduction and cannulated cancellous screw fixation gives satisfactory functional results in large group of elderly patients. The four quadrant parallel peripheral (FQPP screw fixation technique gives good stability, allows controlled collapse, avoids fixation failure and achieves predictable bone healing in displaced femoral neck fracture in patients ?50 years of age.

  4. Experimental and simulated displacement of oil in sand berea cores using aqueous solutions

    International Nuclear Information System (INIS)

    The development of a mathematical algorithm to simulate the displacement of a resident fluid using a displacing one in a saturated anisotropic porous media is shown in this work. The algorithm was included in the simulator developed by the present authors in previous works to represent the anisotropic distribution of the porous media properties and the fluid injection [Ramirez A et al. Mathematical simulation of oil reservoir properties. Chaos, solitons and Fractals 2008;38:778-88, Ramirez A et al. Simulation of uncompressible fluid flow through a porous media. Chaos, Solitons and Fractals 2009;39:1753-63] in a nested loop to analyze the participant nodes in the transport process and calculate the volumes of the resident and new fluids. The new routine developed takes in count the mobility of both fluids. Additionally experimental fluid displacement tests were done using heavy oil from Mexican reservoirs as a resident fluid in sand berea cores. The injection of new fluids in natural oil reservoirs is a part of the Enhanced oil recovery (EOR) methods used to improve the oil displacement and increase production after the primary stage of the oil recovery has been finished. Water is an available and economical resource to be used as a displacing fluid due to many of the producers (off-shores) of the oil industries are placed in the sea near the coast.

  5. Experimental investigation of the displacement of viscous fluids from porous media

    Science.gov (United States)

    Baryshnikov, Nikolay; Belyakov, Georgy; Tairova, Aliya; Turuntaev, Sergey

    2015-04-01

    The problems of increase of oil recover by means of a reservoir flooding are considered as a basis for the study. The results of laboratory experimental investigations of different-viscosity and immiscible Newtonian fluid flows through porous media are presented. The investigations were carried out for a Hele-Shaw cell filled by two types of porous media. The basic difference from the previous studies is the observation of the flow after break-through of the displacing fluid into sink. A series of qualitative and quantitative results which clarify the physics of immiscible fluid flows through capillaries and porous media were obtained in the course of the experimental investigations. Experiments carried out confirm the proposition of the Saffman-Taylor theory concerning the instability of the displacement front when a lower-viscosity fluid displaces a higher-viscosity fluid. It was found that the unstable flow pattern is determined not by the length of the capillary wave which disrupts the flow but by the geometry of the pore space. Experiments on the displacement of oil from capillary by water show that the oil can be completely driven out of the capillary due to the development of wavy flow after the displacing fluid arrives at the capillary outlet.

  6. Test of cold denaturation mechanism for proteins as a function of water's structure

    CERN Document Server

    Marques, M I

    2006-01-01

    In a recent paper [PRL 91, 138103 (2003)] a new mechanism to explain the cold denaturation of proteins, based on the loss of local low-density water structure, has been proposed. In the present paper this mechanism is tested by means of full atom numerical simulations. In good agreement with this proposal, cold denaturation resulting in the unfolded state was found at the High Density Liquid (HDL) state of water, at which the amount of open tetragonal hydrogen bonds decreases at cooling.

  7. Communication: Chemical functionality of interfacial water enveloping nanoscale structural defects in proteins

    Science.gov (United States)

    Fernández, Ariel

    2014-06-01

    Building upon a non-Debye multiscale treatment of water dielectrics, this work reveals the biochemical role of interfacial water enveloping nanoscale structural defects in soluble proteins, asserting its role as a chemical base. This quasi-reactant status is already implied by the significant concentration of structural defects in the vicinity of an enzymatically active site, delineating their role as promoters or enhancers of catalytic activity.

  8. Effect of a natural mineral-rich water on catechol-O-methyltransferase function.

    Science.gov (United States)

    Bastos, Pedro; Araújo, João Ricardo; Azevedo, Isabel; Martins, Maria João; Ribeiro, Laura

    2014-01-01

    Catechol-O-methyltransferase (COMT) is a magnesium-dependent, catecholamine-metabolizing enzyme, whose impaired activity has been positively associated with cardiovascular diseases, particularly hypertension. Consumption of some natural mineral-rich waters has been shown to exert protective effects on cardiovascular risk factors, eg. by decreasing arterial blood pressure and blood lipids. However, the molecular mechanisms underlying these effects are still poorly understood. So, the aim of this work was to investigate the effect of natural mineral-rich water ingestion upon liver and adrenal glands COMT expression and activity in Wistar Han rats. Over a seven-week period, animals had access to one of the following three drinking solutions: 1) tap water (control group; TW), 2) tap water with added Na(+) (to make the same concentration as in the MW group (TWNaCl group), or 3) natural mineral-rich water [Pedras Salgadas(®), which is very rich in bicarbonate, and with higher sodium, calcium and magnesium content than control tap water (MW group)]. COMT expression and activity were determined by RT-PCR and HPLC-ED, respectively. A higher hepatic COMT activity was found in the MW group compared with the TW and TWNaCl groups. On the other hand, adrenal gland COMT mRNA expression decreased in the MW group compared to TW group. In conclusion, the ability of natural mineral-rich waters to increase hepatic COMT activity may eventually explain the positive cardiovascular effects associated with the consumption of some natural mineral-rich waters. PMID:25560240

  9. Towards the generation of fully functioning biomimetic analytical platforms for water quality analysis using ionogel

    OpenAIRE

    Czugala, Monika; Benito-Lopez, Fernando; Diamond, Dermot

    2011-01-01

    Increased demand for improved water management with greatly improved price/performance characteristics is a driving need for water quality monitoring systems. Typical analysis methods are very costly and time consuming, therefore simple, rapid, accurate, cost-effective field-deployable sensors incorporating wireless communication capabilities need to be developed. The main requirements of these sensors such as reproducibility, low cost as well as selectivity and sensitivity must be met for sc...

  10. Benefit of warm water immersion on biventricular function in patients with chronic heart failure

    OpenAIRE

    Kardassis Dimitris; Angwald Eva; Täng Margareta; Cider Åsa; Grüner Sveälv Bente; Andersson Bert

    2009-01-01

    Abstract Background Regular physical activity and exercise are well-known cardiovascular protective factors. Many elderly patients with heart failure find it difficult to exercise on land, and hydrotherapy (training in warm water) could be a more appropriate form of exercise for such patients. However, concerns have been raised about its safety. The aim of this study was to investigate, with echocardiography and Doppler, the acute effect of warm water immersion (WWI) and effect of 8 weeks of ...

  11. Measuring fast stochastic displacements of bio-membranes with dynamic optical displacement spectroscopy.

    Science.gov (United States)

    Monzel, C; Schmidt, D; Kleusch, C; Kirchenbüchler, D; Seifert, U; Smith, A-S; Sengupta, K; Merkel, R

    2015-01-01

    Stochastic displacements or fluctuations of biological membranes are increasingly recognized as an important aspect of many physiological processes, but hitherto their precise quantification in living cells was limited due to a lack of tools to accurately record them. Here we introduce a novel technique-dynamic optical displacement spectroscopy (DODS), to measure stochastic displacements of membranes with unprecedented combined spatiotemporal resolution of 20?nm and 10??s. The technique was validated by measuring bending fluctuations of model membranes. DODS was then used to explore the fluctuations in human red blood cells, which showed an ATP-induced enhancement of non-Gaussian behaviour. Plasma membrane fluctuations of human macrophages were quantified to this accuracy for the first time. Stimulation with a cytokine enhanced non-Gaussian contributions to these fluctuations. Simplicity of implementation, and high accuracy make DODS a promising tool for comprehensive understanding of stochastic membrane processes. PMID:26437911

  12. Biocompatible post-polymerization functionalization of a water soluble poly(p-phenylene ethynylene)

    OpenAIRE

    Swager, Timothy Manning; Vanveller, Brett Steven

    2010-01-01

    A biocompatible post-polymerization functionalization reaction takes advantage of a polymer's structural motif for the controllable attachment of biotin as a model biosensor that responds to streptavidin.

  13. Superconducting inductive displacement detection of a microcantilever

    Energy Technology Data Exchange (ETDEWEB)

    Vinante, A., E-mail: anvinante@fbk.eu [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy)

    2014-07-21

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100??T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2?K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  14. APPLICATION OF GPS DISPLACEMENT MEASUREMENTS FOR MONITORING SLOPE DISPLACEMENTS AT A TUNNEL ENTRANCE

    Science.gov (United States)

    Matsuda, Hiroaki; Tsutsui, Takanori; Ikeda, Keisuke; Shimizu, Norikazu

    A GPS displacement measurement system has been widely used for monitoring the slope stability. Tall trees and other obstacles on the slope often cause a disturbance to the signals transmitted from the satellites and a degradation of the measurement accuracy. It is an important issue to be overcome for applying GPS to monitoring the deformation of slopes. In this paper, "the mask method" developed by the authors is adopted for improving the measurement accuracy under overhead obstacles. It is proven that the method was effective for monitoring a slope at a tunnel entrance during tunnel construction. The measured results of three dimensional displacements are discussed for assessing the slope stability.

  15. Application of proving-ring technology to measure thermally induced displacements in large boreholes in rock

    International Nuclear Information System (INIS)

    A strain-gauged proving-ring transducer was designed and deployed to measure small diametral displacements in 0.61-m diameter boreholes in rock. The rock surrounding the boreholes was previously heated by storage of spent nuclear fuel assemblies and measurements during post-retrieval cooling of the rock were made. To accomplish this, a transducer was designed to measure displacements in the range of 10 to 100 ?m, to function in a time-varying temperature regime of 300 to 600C at a relative humidity of 100%, to be of low stiffness, and to be easily and quickly installed. 7 references, 6 figures, 1 table

  16. Transport of Pseudomonas fluorescens strain P17 through quartz sand columns as a function of water content

    Science.gov (United States)

    Jewett, David G.; Logan, Bruce E.; Arnold, Robert G.; Bales, Roger C.

    1999-02-01

    Porous media column experiments were used to investigate Pseudomonas fluorescens strain P17 transport as a function of water content and the influences of the solid-liquid and gas-liquid interfaces. Retention of radiolabeled P17 in washed quartz sand was evaluated at 100, 84, and 46% water saturation. At the completion of each experiment, the porous medium was extruded and sampled directly for cell retention on the basis of a radiolabel mass balance. Maximum cell retention occurred in the top centimeter of porous media at all three water contents and decreased with depth in the column. The total fraction of cells retained ( Rt) was inversely proportional to water content, with nearly twice the cell retention at 46% saturation ( Rt=0.95) compared to retention in 100% water-saturated experiments ( Rt=0.50). Total retained cells were further divided into strongly and weakly attached fractions by settling a sample of the porous medium through groundwater to dislodge loosely adhering cells. Cells that became suspended in the solution represented the fraction retained at the gas-liquid interface or weakly attached to the solid-liquid interface ( Rg). Those that remained attached to the porous medium were defined as cells strongly attached to the solid-liquid interface ( Rs). Values of Rg/ Rt were inversely related to water content, while Rs/ Rt decreased with decreasing saturation. Bacteria thus preferentially accumulated at the gas-liquid interface with total cell removal inversely proportional to water content. The increased retention of bacteria at the gas-liquid interface indicates the presence of the interface is an important factor in limiting pathogen migration, evaluating biocolloid-facilitated transport of pollutants, and developing bioremediation strategies for unsaturated porous media.

  17. Functional characterization of water transport and cellular localization of three aquaporin paralogs in the salmonid intestine.

    Directory of Open Access Journals (Sweden)

    SteffenSMadsen

    2011-09-01

    Full Text Available Intestinal water absorption is greatly enhanced in salmonids upon acclimation from freshwater (FW to seawater (SW; however, the molecular mechanism for water transport is unknown. We conducted a pharmacological characterization of water absorption in the rainbow trout intestine along with an investigation of the distribution and cellular localization of 3 aquaporins (Aqp1aa, -1ab and -8ab in pyloric caeca, middle (M and posterior (P intestine of the Atlantic salmon. In vitro iso-osmotic water absorption (Jv was higher in SW than FW-trout and was inhibited by (mmol L-1: 0.1 KCN (41%, 0.1 ouabain (72% and 0.1 bumetanide (82% suggesting that active transport, Na+,K+-ATPase and Na+,K+,2Cl--cotransport are involved in establishing the driving gradient for water transport. Jv was also inhibited by 1 mmol L-1 HgCl2, serosally (23% in M and 44% in P, mucosally (27% in M or both (61% in M and 58% in P, suggesting involvement of both apical and basolateral aquaporins in water transport. The inhibition was antagonized by 5 mmol L-1 mercaptoethanol. By comparison, 10 mmol L-1 mucosal tetraethylammonium, an inhibitor of certain aquaporins, inhibited Jv by 20%. In the presence of glucose, mucosal addition of phloridzin inhibited water transport by 20%, suggesting that water transport is partially linked to the Na+-glucose cotransporter. Using polyclonal antibodies against salmon Aqp1aa, -1ab and -8ab, we detected Aqp1aa, and -1ab immunoreactivity in the brush border and sub-apical region of enterocytes in all intestinal segments. The Aqp8ab antibody showed a particularly strong immunoreaction in the brush border and sub-apical region of enterocytes throughout the intestine and also stained lateral membranes and peri-nuclear regions though at lower intensity. The present localization of 3 aquaporins in both apical and lateral membranes of salmonid enterocytes facilitates a model for transcellular water transport in the intestine of SW-acclimated salmonids.

  18. Functional characterization of water transport and cellular localization of three aquaporin paralogs in the salmonid intestine

    DEFF Research Database (Denmark)

    Madsen, Steffen S; Olesen, Jesper H

    2011-01-01

    Intestinal water absorption is greatly enhanced in salmonids upon acclimation from freshwater (FW) to seawater (SW); however, the molecular mechanism for water transport is unknown. We conducted a pharmacological characterization of water absorption in the rainbow trout intestine along with an investigation of the distribution and cellular localization of three aquaporins (Aqp1aa, -1ab, and -8ab) in pyloric caeca, middle (M), and posterior (P) intestine of the Atlantic salmon. In vitro iso-osmotic water absorption (J(v)) was higher in SW than FW-trout and was inhibited by (mmol L(-1)): 0.1 KCN (41%), 0.1 ouabain (72%), and 0.1 bumetanide (82%) suggesting that active transport, Na(+), K(+)-ATPase and Na(+), K(+), 2Cl(-)-co-transport are involved in establishing the driving gradient for water transport. J(v) was also inhibited by 1?mmol?L(-1) HgCl(2), serosally (23% in M and 44% in P), mucosally (27% in M), or both (61% in M and 58% in P), suggesting involvement of both apical and basolateral aquaporins in water transport. The inhibition was antagonized by 5?mmol?L(-1) mercaptoethanol. By comparison, 10?mmol?L(-1) mucosal tetraethylammonium, an inhibitor of certain aquaporins, inhibited J(v) by 20%. In the presence of glucose, mucosal addition of phloridzin inhibited water transport by 20%, suggesting that water transport is partially linked to the Na(+)-glucose co-transporter. Using polyclonal antibodies against salmon Aqp1aa, -1ab, and -8ab, we detected Aqp1aa, and -1ab immunoreactivity in the brush border and sub-apical region of enterocytes in all intestinal segments. The Aqp8ab antibody showed a particularly strong immunoreaction in the brush border and sub-apical region of enterocytes throughout the intestine and also stained lateral membranes and peri-nuclear regions though at lower intensity. The present localization of three aquaporins in both apical and lateral membranes of salmonid enterocytes facilitates a model for transcellular water transport in the intestine of SW-acclimated salmonids.

  19. Pulse tube stirling machine with warm gas-driven displacer

    Science.gov (United States)

    Zhu, Shaowei; Nogawa, Masafumi

    2010-05-01

    A pulse tube type stirling machine with warm gas-driven displacer which has a displacer rod is discussed with numerical simulation when it is used as a cryogenic refrigerator, room temperature refrigerator and engine. It has both the advantages of gas-driven-stirling machine with high efficiency and simplicity and the advantages of pulse tube machine with no moving parts at low temperatures. A nodal analysis method that includes the linear motor and the displacer in the machine is introduced. Numerical results show that it has high potential to be used as the cryogenic refrigerator, room temperature refrigerator and engine. In this type of machine, there is an optimum phase angle between displacer and piston, and an optimum swept volume ratio of displacer over compressor for efficiency. The phase angle and swept volume ratio can be adjusted by the natural frequency of the displacer and the diameter of the displacer rod when it is used as a refrigerator.

  20. Hydrodynamic Excitation Forces on Floating Structures with Finite Displacements

    DEFF Research Database (Denmark)

    Andersen, Morten ThØtt; Nielsen, SØren R. K.

    2015-01-01

    This paper aims to present an extended version of the classic linear wave excitation force theory. Linear wave theory implies that the wave load is applied in the referential state of the structure. In reality, the load is acting in the dynamically altered state. In the classic notation the wave excitation force is solely a function of time, hence the body is fixed in reference to the wave field. In this paper, the instantaneous position of the body is included in the calculation of the excitation force. Even though the displacement of the structure relative to a characteristic wavelength is generally small, it is demonstrated that the indicated nonlinear effect causes parametric instability at certain ratios between the wave frequency and the eigenfrequency of the structure. This calls for caution for structures designed to avoid resonance by having eigenfrequencies below the exciting wave frequencies.

  1. Heavy metal displacement in chelate-irrigated soil during phytoremediation

    Science.gov (United States)

    Madrid, F.; Liphadzi, M. S.; Kirkham, M. B.

    2003-03-01

    Heavy metals in wastewater sewage sludge (biosolids), applied to land, contaminate soils. Phytoremediation, the use of plants to clean up toxic heavy metals, might remove them. Chelating agents are added to soil to solubilize the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with and without roots following solubilization with chelates. The objective of this work was to determine the mobility of heavy metals in biosolids applied to the surface of soil columns (76 cm long; 17 cm diam.) with or without plants (barley; Hordeum vulgare L.). Three weeks after barley was planted, all columns were irrigated with the disodium salt of the chelating agent, EDTA (ethylenediamine tetraacetic acid) (0.5 g/kg soil). Drainage water, soil, and plants were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, Zn). Total concentrations of the heavy metals in all columns at the end of the experiment generally were lower in the top 30 cm of soil with EDTA than without EDTA. The chelate increased concentrations of heavy metals in shoots. With or without plants, the EDTA mobilized Cd, Fe, Mn, Ni, Pb, and Zn, which leached to drainage water. Drainage water from columns without EDTA had concentrations of these heavy metals below detection limits. Only Cu did not leach in the presence of EDTA. Even though roots retarded the movement of Cd, Fe, Mn, Ni, Pb, and Zn through the EDTA-treated soil from 1 d (Cd) to 5 d (Fe), the drainage water from columns with EDTA had concentrations of Cd, Fe, Mn, and Pb that exceeded drinking water standards by 1.3, 500, 620, and 8.6 times, respectively. Because the chelate rendered Cd, Fe, Mn, Ni, Pb, and Zn mobile, it is suggested that the theory for leaching of soluble salts, put forward by Nielsen and associates in 1965, could be applied to control movement of the heavy metals for maximum uptake during chelate-assisted phytoremediation.

  2. Immersion Freezing of Water and Aqueous Ammonium Sulfate Droplets Initiated by Humic-Like Substances as a Function of Water Activity

    Science.gov (United States)

    Rigg, Y.; Alpert, P. A.; Knopf, D. A.

    2013-12-01

    Immersion freezing of water and aqueous (NH4)2SO4 droplets containing leonardite (LEO) and pahokee peat (PP) serving as surrogates for humic-like substances (HULIS) has been investigated. Organic aerosol containing HULIS are ubiquitous in the atmosphere; however, their potential for ice cloud formation is uncertain. Immersion freezing has been studied for temperatures as low as 215 K and solution water activity, aw, from 0.85 to 1.0. The freezing temperatures of water and aqueous solution droplets containing LEO and PP are 5-15 K warmer than homogeneous ice nucleation temperatures. Heterogeneous freezing temperatures can be represented by a horizontal shift of the ice melting curve as a function of solution aw and ?aw by 0.2703 and 0.2466, respectively. Corresponding heterogeneous ice nucleation rate coefficients, Jhet, are (9.6×2.5)x104 and (5.4×1.4)x104 cm-2 s-1 for LEO and PP containing droplets, respectively, and remain constant along freezing curves characterized by ?aw. Consequently predictions of freezing temperatures and kinetics can be made without knowledge of the solute type when relative humidity and ice nuclei (IN) surface areas are known. The acquired ice nucleation data are applied to evaluate different approaches to fit and reproduce experimentally derived frozen fractions. In addition, we apply a basic formulation of classical nucleation theory (?(T)-model) to calculate contact angles and frozen fractions. Contact angles calculated for each ice nucleus as a function of temperature, ?(T)-model, reproduce exactly experimentally derived frozen fractions without involving free-fit parameters. However, assigning the IN a single contact angle for the entire population (single-? model) is not suited to represent the frozen fractions. Application of ?-PDF, active sites, and deterministic model approaches to measured frozen fractions yield similar good representations. Furthermore, when using a single parameterization of ?-PDF or active sites distribution to fit all individual aw immersion freezing data simultaneously, frozen fraction curves are not reproduced. This implies that these fitting formulations cannot be applied to immersion freezing of aqueous solutions, and suggests that derived fit parameters do not represent independent particle properties. Thus, from fitting frozen fractions only, the underlying ice nucleation mechanism and nature of the ice nucleating sites cannot be inferred. In contrast to using fitted functions obtained to represent experimental conditions only, we suggest to use experimentally derived Jhet as a function of temperature and aw that can be applied to conditions outside of those probed in laboratory. This is because Jhet(T) is independent of time and IN surface areas in contrast to the fit parameters obtained by representation of experimentally derived frozen fractions.

  3. Immersion freezing of water and aqueous ammonium sulfate droplets initiated by humic-like substances as a function of water activity

    Directory of Open Access Journals (Sweden)

    Y. J. Rigg

    2013-07-01

    Full Text Available Immersion freezing of water and aqueous (NH42SO4 droplets containing leonardite (LEO and Pahokee peat (PP serving as surrogates for humic-like substances (HULIS has been investigated. Organic aerosol containing HULIS are ubiquitous in the atmosphere; however, their potential for ice cloud formation is uncertain. Immersion freezing has been studied for temperatures as low as 215 K and solution water activity, aw, from 0.85 to 1.0. The freezing temperatures of water and aqueous solution droplets containing LEO and PP are 5–15 K warmer than homogeneous ice nucleation temperatures. Heterogeneous freezing temperatures can be represented by a horizontal shift of the ice melting curve as a function of solution aw by ?aw = 0.2703 and 0.2466, respectively. Corresponding hetrogeneous ice nucleation rate coefficients, Jhet, are (9.6 ± 2.5×104 and (5.4 ± 1.4×104 cm?2 s?1 for LEO and PP containing droplets, respectively, and remain constant along freezing curves characterized by ?aw. Consequently predictions of freezing temperatures and kinetics can be made without knowledge of the solute type when relative humidity and ice nuclei (IN surface areas are known. The acquired ice nucleation data are applied to evaluate different approaches to fit and reproduce experimentally derived frozen fractions. In addition, we apply a basic formulation of classical nucleation theory (?(T-model to calculate contact angles and frozen fractions. Contact angles calculated for each ice nucleus as a function of temperature, ?(T-model, reproduce exactly experimentally derived frozen fractions without involving free-fit parameters. However, assigning the IN a single contact angle for the entire population (single-? model is not suited to represent the frozen fractions. Application of ?-PDF, active sites, and deterministic model approaches to measured frozen fractions yield similar good representations. Furthermore, when using a single parameterization of ?-PDF or active sites distribution to fit all individual aw immersion freezing data simultaneously, frozen fraction curves are not reproduced. This implies that these fitting formulations cannot be applied to immersion freezing of aqueous solutions, and suggests that derived fit parameters do not represent independent particle properties. Thus, from fitting frozen fractions only, the underlying ice nucleation mechanism and nature of the ice nucleating sites cannot be inferred. In contrast to using fitted functions obtained to represent experimental conditions only, we suggest to use experimentally derived Jhet as a function of temperature and aw that can be applied to conditions outside of those probed in laboratory. This is because Jhet(T is independent of time and IN surface areas in contrast to the fit parameters obtained by representation of experimentally derived frozen fractions.

  4. Sperm competition games: Sperm size (mass) and number under raffle and displacement, and the evolution of P2

    OpenAIRE

    Parker, G. A.; Immler, S; Pitnick, S.; Birkhead, T R

    2010-01-01

    Abstract We examine models for evolution of sperm size (i.e. mass m) and number (s) under three mechanisms of sperm competition at low ‘risk’ levels: (i) raffle with no constraint on space available for competing sperm, (ii) direct displacement mainly by seminal fluid, and (iii) direct displacement mainly by sperm mass. Increasing sperm mass increases a sperm's ‘competitive weight’ against rival sperm through a diminishing returns function, r(m). ESS total ejaculate expenditure (th...

  5. Adsorption of surface functionalized silica nanoparticles onto mineral surfaces and decane/water interface

    International Nuclear Information System (INIS)

    The adsorption of silica nanoparticles onto representative mineral surfaces and at the decane/water interface was studied. The effects of particle size (the mean diameters from 5 to 75 nm), concentration and surface type on the adsorption were studied in detail. Silica nanoparticles with four different surfaces [unmodified, surface modified with anionic (sulfonate), cationic (quaternary ammonium (quat)) or nonionic (polyethylene glycol (PEG)) surfactant] were used. The zeta potential of these silica nanoparticles ranges from ?79.8 to 15.3 mV. The shape of silica particles examined by a Hitachi-S5500 scanning transmission electron microscope (STEM) is quite spherical. The adsorption of all the nanoparticles (unmodified or surface modified) on quartz and calcite surfaces was found to be insignificant. We used interfacial tension (IFT) measurements to investigate the adsorption of silica nanoparticles at the decane/water interface. Unmodified nanoparticles or surface modified ones with sulfonate or quat do not significantly affect the IFT of the decane/water interface. It also does not appear that the particle size or concentration influences the IFT. However, the presence of PEG as a surface modifying material significantly reduces the IFT. The PEG surface modifier alone in an aqueous solution, without the nanoparticles, yields the same IFT reduction for an equivalent PEG concentration as that used for modifying the surface of nanoparticles. Contact angle measurements of a decane droplet on quartz or calcite plate immersed in water (or aqueous nanoparticle dispersion) showed a slight change in the contact angle in the presence of the studied nanoparticles. The results of contact angle measurements are in good agreement with experiments of adsorption of nanoparticles on mineral surfaces or decane/water interface. This study brings new insights into the understanding and modeling of the adsorption of surface-modified silica nanoparticles onto mineral surfaces and water/decane interface.

  6. Calibrating the Shan-Chen lattice Boltzmann model for immiscible displacement in porous media

    DEFF Research Database (Denmark)

    Christensen, Britt StenhØj Baun; Schaap, M.G.

    2006-01-01

    The lattice Boltzmann (LB) modeling technique is increasingly being applied in a variety of fields where computational fluid dynamics are investigated. In our field of interest, environmentally related flow processes in porous media, the use of the LB method is still not common. For the LB technique to become a truly valuable modeling tool, a proper link between the dimensionless LB model and physical characteristics of the system of interest has to be made. We describe how this connection can be made, presenting a procedure for identifying LB model parameters, and relating them to a specific physical system; in this case observed oil-water displacement experiments. For this purpose, we use simple, well-characterized, two-fluid-phase systems that furthermore function as a test of the code. The calibrated model is shown to produce realistic capillary pressures, within the pressure range of the observed experimental system. The model calibration procedure does not result in a unique parameter set; instead several parameter sets that appear equally reasonable are obtained. We discuss 2 problems and limitations of the approach as applied using a multicomponent version of the Shan-Chen LB model.

  7. Transient digitizer with displacement current samplers

    Science.gov (United States)

    McEwan, Thomas E. (Livermore, CA)

    1996-01-01

    A low component count, high speed sample gate, and digitizer architecture using the sample gates is based on use of a signal transmission line, a strobe transmission line and a plurality of sample gates connected to the sample transmission line at a plurality of positions. The sample gates include a strobe pickoff structure near the strobe transmission line which generates a charge displacement current in response to propagation of the strobe signal on the strobe transmission line sufficient to trigger the sample gate. The sample gate comprises a two-diode sampling bridge and is connected to a meandered signal transmission line at one end and to a charge-holding cap at the other. The common cathodes are reverse biased. A voltage step is propagated down the strobe transmission line. As the step propagates past a capacitive pickoff, displacement current i=c(dv/dT), flows into the cathodes, driving the bridge into conduction and thereby charging the charge-holding capacitor to a value related to the signal. A charge amplifier converts the charge on the charge-holding capacitor to an output voltage. The sampler is mounted on a printed circuit board, and the sample transmission line and strobe transmission line comprise coplanar microstrips formed on a surface of the substrate. Also, the strobe pickoff structure may comprise a planar pad adjacent the strobe transmission line on the printed circuit board.

  8. Histone displacement during nucleotide excision repair

    DEFF Research Database (Denmark)

    Dinant, C.; Bartek, J.

    2012-01-01

    Nucleotide excision repair (NER) is an important DNA repair mechanism required for cellular resistance against UV light and toxic chemicals such as those found in tobacco smoke. In living cells, NER efficiently detects and removes DNA lesions within the large nuclear macromolecular complex called chromatin. The condensed nature of chromatin inhibits many DNA metabolizing activities, including NER. In order to promote efficient repair, detection of a lesion not only has to activate the NER pathway but also chromatin remodeling. In general, such remodeling is thought on the one hand to precede NER, thus allowing repair proteins to efficiently access DNA. On the other hand, after completion of the repair, the chromatin must be returned to its previous undamaged state. Chromatin remodeling can refer to three separate but interconnected processes, histone post-translational modifications, insertion of histone variants and histone displacement (including nucleosome sliding). Here we review current knowledge, and speculate about current unknowns, regarding those chromatin remodeling activities that physically displace histones before, during and after NER. © 2012 by the authors; licensee MDPI, Basel, Switzerland.

  9. Microglial displacement of inhibitory synapses provides neuroprotection in the adult brain.

    Science.gov (United States)

    Chen, Zhihong; Jalabi, Walid; Hu, Weiwei; Park, Hyun-Joo; Gale, John T; Kidd, Grahame J; Bernatowicz, Rodica; Gossman, Zachary C; Chen, Jacqueline T; Dutta, Ranjan; Trapp, Bruce D

    2014-01-01

    Microglia actively survey the brain microenvironment and play essential roles in sculpting synaptic connections during brain development. While microglial functions in the adult brain are less clear, activated microglia can closely appose neuronal cell bodies and displace axosomatic presynaptic terminals. Microglia-mediated stripping of presynaptic terminals is considered neuroprotective, but the cellular and molecular mechanisms are poorly defined. Using 3D electron microscopy, we demonstrate that activated microglia displace inhibitory presynaptic terminals from cortical neurons in adult mice. Electrophysiological recordings further establish that the reduction in inhibitory GABAergic synapses increased synchronized firing of cortical neurons in ?-frequency band. Increased neuronal activity results in the calcium-mediated activation of CaM kinase IV, phosphorylation of CREB, increased expression of antiapoptotic and neurotrophic molecules and reduced apoptosis of cortical neurons following injury. These results indicate that activated microglia can protect the adult brain by migrating to inhibitory synapses and displacing them from cortical neurons. PMID:25047355

  10. Fabrication and characterization of wide band AE sensors for quantitative detection of displacement and velocity

    International Nuclear Information System (INIS)

    Acoustic emission sensors to show a flat response for displacement and velocity of a specimen surface in a wide frequency were fabricated. The sensors were conical sensors employing conical type piezoelectric elements and a PVDF sensor employing PVDF piezoelctric polymer. The transient outputs of the sensors due to step-like forces and their sensitivity spectrum were measured. The results were compared with the theoretical displacement and velocity signals calculated using Green's function and a simulated ramp force. The sensor outputs and the theoretical signals were consistent with each other. The sensors showed flat sensitivity spectra in the wide frequency range. The present work showed that conical PZT sensors are suited for the direct measurement of vertical displacement, and PVDF sensors for that of the vertical velocity of a plate surface.

  11. Optimum design of seat region in valves suitable for digital displacement machines

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Johansen, Per

    2014-01-01

    Digital displacement fluid power is an upcoming technology setting new standards for the achievable efficiency in variable displacement fluid power pumps and motors. In the present work, an annular seat valve suitable for use in digital displacement units is considered, and the valve geometry is optimised considering both the mechanical strength during pressure loading and fluid flow restriction in the open valve state. Material stresses are modelled using finite element (FE) analysis including non-linear material behaviour, contact elements and fluid pressure penetrating load, closely reflecting the actual load of the seat valve connected to a fluid pressure chamber. Valve pressure losses are modelled using computational fluid dynamics (CFD). On basis of an overall physical size requirement and material specification, optimum valve geometry and stroke length are given as function of a defined normalised flow coefficient directly related to the machine efficiency.

  12. Chicken meat quality as a function of fasting period and water spray

    Scientific Electronic Library Online (English)

    CM, Komiyama; AA, Mendes; SE, Takahashi; J, Moreira; RG, Garcia; C, Sanfelice; HS, Borba; FR, Leonel; ICL, Almeida Paz; A, Balog.

    2008-09-01

    Full Text Available This study aimed at evaluating the effect of different fasting periods and water spray during lairage on the quality of chicken meat. A number of 300 male Ross broilers were reared up to 42 days of age, and submitted to four pre-slaughter fasting periods (4, 8, 12, and 16 hours) and sprayed with wat [...] er or not during lairage. Deboned breast meat was submitted to the following analysis: pH, color, drip loss, water retention capacity, cooking loss, and shear force. There was a significant effect (p

  13. Effects of soil water repellency on microbial community structure and functions in Mediterranean pine forests

    Science.gov (United States)

    Lozano, Elena; Grayston, Sue J.; Mataix-Solera, Jorge; Arcenegui, Victoria; Jimenez-Pinilla, Patricia; Mataix-Beneyto, Jorge

    2015-04-01

    Soil water repellency (SWR) is a property commonly observed in forest areas showing wettable and water repellent patches with high spatial variability. SWR can greatly influence the hydrology and the ecology of forest soils. The capacity of soil microorganisms to degrade different organic compounds depends upon species composition, so this may affect changes in SWR on the microsite scale (such as the presence of soil water repellent patches; Mülleret al., 2010). In the Mediterranean forest context, SWR has been found to be related to microbial community composition. The accumulation of different hydrophobic compounds might be causing the shifts in microbial community structure (Lozano et al., 2014). In this study we investigated the effects of SWR persistence on soil microbial community structure and enzyme activity under Pinus halepensis forest in three different sites: Petrer, Gorga and Jávea (Alicante, E Spain). Soil samples were classified into three different water repellency classes (wettable, slight or strongly water repellent samples) depending on the SWR persistence. The soil microbial community was determined through phospholipid fatty acids (PLFAs). Enzyme activities chosen for this study were cellulase, ?-glucosidase and N-acetyl-?-glucosaminide (NAG). The relationships between microbiological community structure and some soil properties such as pH, Glomalin Related Soil Protein, soil organic matter content and soil respiration were also studied. Redundancy analyses and decomposition of the variances were performed to clarify how microbial community composition and enzyme activities are affected by SWR and soil properties. The effect of SWR on microbial community composition differed between locations. This effect was clearer in the Petrer site. Enzyme activity varied considerably depending on SWR persistence. The highest activities were found in slightly SWR samples and the lowest mostly in the strongly water repellent ones. These preliminary results suggest a possible influence of SWR on microbial structure and its activity in soils. References: Lozano, E., García-Orenes, F., Bárcenas-Moreno, G., Jiménez-Pinilla, P., Mataix-Solera, J., Arcenegui, V., Morugán-Coronado, A., Mataix-Beneyto, J., 2014. Relationships between soil water repellency and microbial community composition under different plant species in a Mediterranean semiarid forest. J. Hydrol. Hydromech., 62, 101-107 Müller, K., Deurer, M., Newton, P.C.D., 2010. Is there a link between elevated atmospheric carbon dioxide concentration, soil water repellency and soil carbon mineralization? Agric. Ecosyst. Environ., 139, 98-109. Acknowledgements: to the "Ministerio de Economía and Competitividad" of Spanish Government for finance the POSTFIRE project (CGL2013- 47862-C2-1-R), Generalitat Valenciana for PhD grant, and Spanish Soil Science Society and FUEGORED for their support.

  14. The impact of land use changes on water pathways, soil formation and soil functioning

    Science.gov (United States)

    Robinet, Jérémy; Ameijeiras-Mariño, Yolanda; Minella, Jean P. G.; Vanderborght, Jan; Govers, Gerard

    2015-04-01

    The major role played by the hydrology in controlling biogeochemical fluxes at various scales has been highlighted in several studies (e.g. Van Gaelen et al., 2014; Jiang et al., 2010). Numerous studies have highlighted different factors controlling water fluxes at the hillslope or catchment scale, such as physico-chemical soil characteristics and structure (Uhlenbrook et al., 2008) and soil thickness (Buttle et al., 2004). Given the potential important impact of land use changes on water fluxes (Özturk et al., 2013), it is surprising that relatively few studies investigated the impacts of those changes. This does not only imply that the consequences of land use change on hydrological and biogeochemical pathways and fluxes are still difficult to predict but also that we lack critical information on how such changes may feed back to soil processes. Therefore, it remains impossible to assess to what extent land use conversions may affect biogeochemical processes in soils and/or soil production through weathering. The overall objective of this research project is therefore to investigate how land use change affects water and biogeochemical fluxes and how these changes may, on their turn, affect soil and landscape development on the long term. In order to achieve this objective it is necessary to not only assess the effect of land use on fluxes leaving the catchment, but also on how land use change affects water pathways and water chemistry within the catchment. This requires the combined use of a wide range of classical and novel techniques. Two catchments with contrasting land use (agriculture vs. natural forest) were selected in a subtropical region in the south of Brazil. Soil sampling, stream discharge monitoring and sampling, pore water sampling, groundwater monitoring and sampling, and geophysical techniques (Time Domain Reflectometry and Electro Magnetic Induction) are combined to yield information on water and solute movement at the plot, slope and catchment scale. The combined interpretation of these information sources will improve our understanding of the interactions between the water fluxes and the soil system under different land use systems. Combining these data with detailed studies of clay mineralogy and weathering will allow to gain first insights on how land use changes may affect biogeochemical processes and soil weathering at the landscape scale.

  15. Functional-analytical capabilities of GIS technology in the study of water use risks

    Science.gov (United States)

    Nevidimova, O. G.; Yankovich, E. P.; Yankovich, K. S.

    2015-02-01

    Regional security aspects of economic activities are of great importance for legal regulation in environmental management. This has become a critical issue due to climate change, especially in regions where severe climate conditions have a great impact on almost all types of natural resource uses. A detailed analysis of climate and hydrological situation in Tomsk Oblast considering water use risks was carried out. Based on developed author's techniques an informational and analytical database was created using ArcGIS software platform, which combines statistical (quantitative) and spatial characteristics of natural hazards and socio-economic factors. This system was employed to perform areal zoning according to the degree of water use risks involved.

  16. Electronic structure effects in liquid water studied by photoelectron spectroscopy and density functional theory

    Energy Technology Data Exchange (ETDEWEB)

    Nordlund, Dennis; Odelius, Michael; Bluhm, Hendrik; Ogasawara, Hirohito; Pettersson, Lars G.M.; Nilsson, Anders

    2008-04-29

    We present valence photoelectron emission spectra of liquid water in comparison with gas-phase water, ice close to the melting point, low temperature amorphous and crystalline ice. All aggregation states have major electronic structure changes relative to the free molecule, with rehybridization and development of bonding and anti-bonding states accompanying the hydrogen bond formation. Sensitivity to the local structural order, most prominent in the shape and splitting of the occupied 3a{sub 1} orbital, is understood from the electronic structure averaging over various geometrical structures, and reflects the local nature of the orbital interaction.

  17. Transport behavior of functionalized multi-wall carbon nanotubes in water-saturated quartz sand as a function of tube length.

    Science.gov (United States)

    Wang, Yonggang; Kim, Jae-Hong; Baek, Jong-Beom; Miller, Gary W; Pennell, Kurt D

    2012-09-15

    A series of one-dimensional column experiments was conducted to examine the effects of tube length on the transport and deposition of 4-ethoxybenzoic acid functionalized multi-wall carbon nanotubes (MWCNTs) in water-saturated porous media. Aqueous MWCNTs suspensions were prepared to yield three distributions of tube lengths; 0.02-1.3 ?m (short), 0.2-7.5 ?m (medium), and 0.2-21.4 ?m (long). Results of the column studies showed that MWCNT retention increased with increasing tube length. Nevertheless, more than 76% of the MWCNT mass delivered to the columns was detected in effluent samples under all experimental conditions, indicating that the functionalized MWCNTs were readily transported through 40-50 mesh Ottawa sand. Examination of MWCNT length distributions in the effluent samples revealed that nanotubes with lengths greater than 8 ?m were preferentially deposited. In addition, measured retention profiles exhibited the greatest MWCNT deposition near the column inlet, which was most pronounced for the long MWCNTs, and decreased sharply with travel distance. Scanning electron microscope (SEM) images showed that MWCNTs were deposited on sand surfaces over the entire column length, while larger MWCNT bundles were retained at grain intersections and near the column inlet. A mathematical model based on clean bed filtration theory (CBFT) was unable to accurately simulate the measured retention profile data, even after varying the weighting function and incorporating a nonuniform attachment rate coefficient expression. Modification of the mathematical model to account for physical straining greatly improved predictions of MWCNT retention, yielding straining rate coefficients that were four orders-of-magnitude greater than corresponding attachment rate coefficients. Taken in concert, these experimental and modeling results demonstrate the potential importance of, and need to consider, particle straining and tube length distribution when describing MWCNT transport in water-saturated porous media. PMID:22704927

  18. The Green's function nodal expansion method for light water reactor diffusion calculations

    International Nuclear Information System (INIS)

    Green's function nodal expansion method (GNEM) is developed for the efficient numerical solution of the multidimensional neutron diffusion equation. It is an improved version of the nodal expansion method (NEM) and the nodal Green's function method (NGFM). The node interior fluxes are approximated by a high-order polynomial expansion as in NEM. The nodal surface fluxes are coupled with the net currents by using the Green's function method to improve accuracy. The GNEM computer code is encoded and tested. The numerical results demonstrate that GNEM has the same accuracy as NGFM while it is twice as fast as NGFM

  19. Off-Axis Gaussian Beams with Random Displacement in Atmospheric Turbulence

    Directory of Open Access Journals (Sweden)

    Yahya Baykal

    2006-10-01

    Full Text Available Our recent work in which we study the propagation of the general Hermite-sinusoidal-Gaussian laser beams in wireless broadband access telecommunication systems is elaborated in this paper to cover the special case of an off-axis Gaussian beam. We mainly investigate the propagation characteristics in atmospheric turbulence of an off-axis Gaussian beam possessing Gaussian distributed random displacement parameters. Our interest is to search for different types of laser beams that will improve the performance of a wireless broadband access system when atmospheric turbulence is considered. Our formulation is based on the basic solution of the second order mutual coherence function evaluated at the receiver plane. For fixed turbulence strength, the coherence length calculated at the receiver plane is found to decrease as the variance of the random displacement is increased. It is shown that as the turbulence becomes stronger, coherence lengths due to off-axis Gaussian beams tend to approach the same value, irrespective of the variance of the random displacement. As expected, the beam spreading is found to be pronounced for larger variance of displacement parameter. Average intensity profiles when atmospheric turbulence is present are plotted for different values of the variance of the random displacement parameter of the off-axis Gaussian beam.

  20. Wireless Displacement Sensing of Micromachined Spiral-Coil Actuator Using Resonant Frequency Tracking

    Directory of Open Access Journals (Sweden)

    Mohamed Sultan Mohamed Ali

    2014-07-01

    Full Text Available This paper reports a method that enables real-time displacement monitoring and control of micromachined resonant-type actuators using wireless radiofrequency (RF. The method is applied to an out-of-plane, spiral-coil microactuator based on shape-memory-alloy (SMA. The SMA spiral coil forms an inductor-capacitor resonant circuit that is excited using external RF magnetic fields to thermally actuate the coil. The actuation causes a shift in the circuit’s resonance as the coil is displaced vertically, which is wirelessly monitored through an external antenna to track the displacements. Controlled actuation and displacement monitoring using the developed method is demonstrated with the microfabricated device. The device exhibits a frequency sensitivity to displacement of 10 kHz/µm or more for a full out-of-plane travel range of 466 µm and an average actuation velocity of up to 155 µm/s. The method described permits the actuator to have a self-sensing function that is passively operated, thereby eliminating the need for separate sensors and batteries on the device, thus realizing precise control while attaining a high level of miniaturization in the device.

  1. Thermal regulation of functional groups in running water ecosystems. Progress report, 1974--1975

    International Nuclear Information System (INIS)

    Upper and lower thermal limits and temperature dependent growth were determined for a number of organisms (or populations) representing various functional groups of stream ecosystems (microconsumers, producers, and macroconsumers, shredders, collectors, scrapers, and predators). Although temperature functions as an overall control parameter, organic substrate (microconsumers) and inorganic nutrients (microconsumers and producers), light (producers) and food quality (macroconsumers) can modify thermal responses. Stream microorganisms typically grow below their thermal optima, community composition being determined by those that can manage the maximum growth at a given temperature utilizing a given organic substrate. Producers in first to third order streams are generally light limited (although nutrient availability is also important). Food quality, primarily a function of microbial biomass in the case of detritivores. can compensate for temperature dependent growth in non-predator macroinvertebrate functional groups. (U.S.)

  2. An Instrument for In Situ Measuring the Volume Scattering Function of Water: Design, Calibration and Primary Experiments

    Directory of Open Access Journals (Sweden)

    Chaoying Guo

    2012-04-01

    Full Text Available The optical volume scattering function (VSF of seawater is a fundamental property used in the calculation of radiative transfer for applications in the study of the upper-ocean heat balance, the photosynthetic productivity of the ocean, and the chemical transformation of photoreactive compounds. A new instrument to simultaneously measure the VSF in seven directions between 20° to 160°, the attenuation coefficient, and the depth of water is presented. The instrument is self-contained and can be automatically controlled by the depth under water. The self-contained data can be easily downloaded by an ultra-short-wave communication system. A calibration test was performed in the laboratory based on precise estimation of the scattering volume and optical radiometric calibration of the detectors. The measurement error of the VSF measurement instrument has been estimated in the laboratory based on the Mie theory, and the average error is less than 12%. The instrument was used to measure and analyze the variation characteristics of the VSF with angle, depth and water quality in Daya Bay for the first time. From these in situ data, we have found that the phase functions proposed by Fournier-Forand, measured by Petzold in San Diego Harbor and Sokolov in Black Sea do not fit with our measurements in Daya. These discrepancies could manly due to high proportion of suspended calcium carbonate mineral-like particles with high refractive index in Daya Bay.

  3. Ankle Dorsiflexion Displacement During Landing is Associated With Initial Contact Kinematics but not Joint Displacement.

    Science.gov (United States)

    Begalle, Rebecca L; Walsh, Meghan C; McGrath, Melanie L; Boling, Michelle C; Blackburn, J Troy; Padua, Darin A

    2015-08-01

    The ankle, knee, and hip joints work together in the sagittal plane to absorb landing forces. Reduced sagittal plane motion at the ankle may alter landing strategies at the knee and hip, potentially increasing injury risk; however, no studies have examined the kinematic relationships between the joints during jump landings. Healthy adults (N = 30; 15 male, 15 female) performed jump landings onto a force plate while three-dimensional kinematic data were collected. Joint displacement values were calculated during the loading phase as the difference between peak and initial contact angles. No relationship existed between ankle dorsiflexion displacement during landing and three-dimensional knee and hip displacements. However, less ankle dorsiflexion displacement was associated with landing at initial ground contact with larger hip flexion, hip internal rotation, knee flexion, knee varus, and smaller plantar flexion angles. Findings of the current study suggest that restrictions in ankle motion during landing may contribute to contacting the ground in a more flexed position but continuing through little additional motion to absorb the landing. Transverse plane hip and frontal plane knee positioning may also occur, which are known to increase the risk of lower extremity injury. PMID:25734492

  4. Shape of a water molecule as function of 0-H separation

    International Nuclear Information System (INIS)

    For smal O-H separation the water molecule becomes linear. The Murrell-Sorbie potential energy surface affords a basis to study the shape of the molecule for larger O-H separation. The possible relevance to H2O outside a metal surface is discussed. (orig.)

  5. Properties of novel anion selective material with DABCO functional groups for alkaline water electrolysis.

    Czech Academy of Sciences Publication Activity Database

    Hnát, J.; Žitka, Jan; Paidar, M.; Bouzek, K.

    Prague : University of Chemistry and Technology, Czech Hydrogen Technology Platform, 2015 - (Bouzek, K.; Doucek, A.). s. 28 ISBN 978-80-7080-920-4. [International Conference on Hydrogen Technologies /6./ - Hydrogen Days 2015. 18.03.2015-20.03.2015, Prague] Institutional support: RVO:61389013 Keywords : alkaline water electrolysis * anion selective polymer electrolyte * zero-gap arrangement Subject RIV: CD - Macromolecular Chemistry

  6. Gastric emptying of water in children with severe functional fecal retention

    OpenAIRE

    V.P.I. Fernandes; M.C.L. Lima; E.E. Camargo; E.F. Collares; J.M. Bustorff-Silva; Lomazi, E.A.

    2013-01-01

    The objective of this study was to evaluate gastric emptying (GE) in pediatric patients with functional constipation. GE delay has been reported in adults with functional constipation. Gastric emptying studies were performed in 22 children with chronic constipation, fecal retention and fecal incontinence, while presenting fecal retention and after resuming regular bowel movements. Patients (18 boys, median age: 10 years; range: 7.2 to 12.7 years) were evaluated in a tertiary pediatric gastroe...

  7. A new methodology for quantifying the impact of water repellency on the filtering function of soils

    Science.gov (United States)

    Müller, Karin; Deurer, Markus; Kawamoto, Ken; Hiradate, Syuntaro; Komatsu, Toshiko; Clothier, Brent

    2014-05-01

    Soils deliver a range of ecosystem services, and some of the most valuable relate to the regulating services resulting from the buffering and filtering of solutes by soil. However, it is commonly accepted that soil water repellency (SWR) can lead to finger flow and preferential flow. Yet, there have been few attempts to quantify the impact of such flow phenomena on the buffering and filtering of solutes. No method is available to quantify directly how SWR affects the transport of reactive solutes. We have closed this gap and developed a new method for quantifying solute transport by novel experiments with water-repellent soils. It involves sequentially applying two liquids, one water, and the other a reference fully wetting liquid, namely, aqueous ethanol, to the same intact soil core with air-drying between the application of the two liquids. Our results highlight that sorption experiments are necessary to complement our new method to ascertain directly the impact of SWR on the filtering of a solute. We conducted transport and sorption experiments, by applying our new method, with the herbicide 2,4-Dichlorophenoxyacetic acid and two Andosol top-soils; one from Japan and the other one from New Zealand. Breakthrough curves from the water experiments were characterized by preferential flow with high initial concentrations, tailing and a long prevalence of solutes remaining in the soil. Our results clearly demonstrate and quantify the impact of SWR on the leaching of this herbicide. This technique for quantifying the reduction of the soil's filtering efficiency by SWR enables assessment of the increased risk of groundwater contamination by solutes exogenously applied to water-repellent soils.

  8. Plankton ecosystem functioning and nitrogen fluxes in the most oligotrophic waters of the Beaufort Sea, Arctic Ocean: a modeling study

    Science.gov (United States)

    Le Fouest, V.; Zakardjian, B.; Xie, H.; Raimbault, P.; Joux, F.; Babin, M.

    2012-10-01

    The Arctic Ocean (AO) undergoes profound changes of its physical and biotic environments due to climate change. The greater light exposure and stratification alter its plankton ecosystem structure, functioning and productivity promoting oligotrophy in some areas as the Beaufort Sea. A one-dimension (1-D) physical-biological coupled model based on the large multiparametric database of the Malina project in the Beaufort Sea was used (i) to infer the functioning and nitrogen fluxes within the summer plankton ecosystem and (ii) to assess the model sensitivity to key light-associated processes involved in nutrient recycling and phytoplankton growth. The coupled model suggested that ammonium photochemically produced from photosensitive dissolved organic nitrogen (i.e. photoammonification process) was a necessary nitrogen source to achieve the observed levels of microbial biomass and production. It contributed to ca. two-thirds and one-third of the simulated surface (0-10 m) and depth-integrated primary and bacterial production, respectively. The model also suggested that carbon to chlorophyll ratios for small (food web competition and realistic nitrogen fluxes in the Beaufort Sea oligotrophic waters. In face of accelerating Arctic warming, more attention should be paid in the future to the mechanistic processes involved in food webs and functional groups competition, nutrient recycling and primary production in poorly productive waters of the AO as they are expected to expand rapidly.

  9. The Structure of Hydrated Electron. Part 1. Magnetic Resonance of Internally Trapping Water Anions: A Density Functional Theory Study

    CERN Document Server

    Shkrob, I A

    2006-01-01

    Density functional theory (DFT) is used to rationalize magnetic parameters of hydrated electron trapped in alkaline glasses as observed using Electron Paramagnetic Resonance (EPR) and Electron Spin Echo Envelope Modulation (ESEEM) spectroscopies. To this end, model water cluster anions (n=4-8 and n=20,24) that localize the electron internally are examined. It is shown that EPR parameters of such water anions (such as hyperfine coupling tensors of H/D nuclei in the water molecules) are defined mainly by the cavity size and the coordination number of the electron; the water molecules in the second solvation shell play a relatively minor role. An idealized model of hydrated electron (that is usually attributed to L. Kevan) in which six hydroxyl groups arranged in an octahedral pattern point towards the common center is shown to provide the closest match to the experimental parameters, such as isotropic and anisotropic hyperfine coupling constants for the protons (estimated from ESEEM), the second moment of the E...

  10. Tensions and displacements calculation produced by a welding process in a nuclear power plant steam generator entrance by the finite element method

    International Nuclear Information System (INIS)

    This paper presents the results obtained from the tensions state and the displacements field of thermal origin, generated by a caloric source during the welding process. All the surfaces in contact with heavy water in a PHWR plant (Reactor of Pressurized Heavy Water) must be of austenitic stainless steel according to standard DIN 1.4550 or must be internally covered with this material. In the case of the primary loop components, -as the steam generator-, the walls of ferritic steel are covered with an austenitic stainless steel cladding. This cladding is applied by the welding process of immersed arc. Special attention is given during calculation, on the deformation produced in the holes of the bolts that link the entrance with the external lead. The distribution of nodal temperatures, as a function of time, is determined by a two-dimensional finite elements model during the welding process and the tension state and the displacement, by means of computational programs, were afterwards calculated. (Author)

  11. Does water activity rule P. mirabilis periodic swarming? I. Biochemical and functional properties of the extracellular matrix.

    Science.gov (United States)

    Lahaye, Elodie; Aubry, Thierry; Kervarec, Nelly; Douzenel, Philippe; Sire, Olivier

    2007-04-01

    The dynamics of bacterial colonies is complex in nature because it correlates the behavior of numerous individual cells in space and time and is characterized by emergent properties such as virulence or antibiotics resistance. Because there is no clear-cut evidence that periodic swarming of P. mirabilis colonies is ruled by chemical triggers responsible for cell-to-cell signaling in most of the biofilms, we propose that the observed periodicity relies on the colony's global properties. Hence, the biochemical and functional properties of the extracellular matrix (ECM) of P. mirabilis colonies were investigated. A binary exopolysaccharide mixture (1 and 300 kDa), glycinebetaine, and a phenoglycolipid were identified. Rheology, calorimetry, and water sorption experiments performed on purified EPS bring evidence that these exoproducts exhibit marked viscoelasticity, which likely relies on large scale H bond networks. Such behavior is discussed in terms of water activity because the mechanical ECM properties were found to depend on hydration. PMID:17355120

  12. Determination of displacement threshold energies in pure Ti and in ?-TiAl alloys by electron irradiation

    International Nuclear Information System (INIS)

    Resistivity damage rates, determined during low-temperature electron irradiations in the energy range 0.3-2.5 MeV, were used for evaluating displacement threshold energies of titanium in high purity hcp titanium, and of titanium and aluminium in ?-TiAl intermetallic compounds. These parameters were deduced from a comparison of experimental displacement cross-section variations as a function of electron energy, with theoretical curves based on a displacement model for diatomic materials. The displacement energy of titanium in hcp titanium appears to depend on the electron energy. A threshold value of 21±1 eV was obtained in the range 0.3-0.5 MeV, and a larger value of 30±2 eV is determined in the range 0.5-2.5 MeV. In ?-TiAl, aluminium atoms are displaced first, with a threshold displacement energy (34±2 eV) larger than the one of titanium atoms, and much higher than the value in pure aluminium. The displacement energy of Ti atoms is 28±2 eV, close to the one obtained in pure titanium under similar conditions. These results were used for re-evaluating the Frenkel-pair resistivity of the stoichiometric TiAl compound. (orig.)

  13. Determination of Alkalinity and dissociation constants of high salinity waters: use of F5BC titration function

    Scientific Electronic Library Online (English)

    B.F, Cavalcanti; L.C.L, Agostinho; L, Nascimento.

    Full Text Available Medições de parâmetros expressos em termos de espécies carbônicas tais como Alcalinidade e Acidez de águas Salinas não analisam a influencia de parâmetros externos tais como Concentração de Espécies Carbônicas livre e associada, formação de pares iônicos e Potencial de Residual de Junção Líquida em [...] medições de pH. Este artigo mostra o desenvolvimento da função titulométrica F5BC com base nas titulações desenvolvidas por Gran (1952) para o sistema carbonatado de águas naturais. Para uso prático, amostras de água salina do açude de Pocinhos, PB foram submetidas à titulação e análise de regressão linear. Os resultados mostraram que a função F5BC compreende a determinação das funções tipo Gran F1x e F2x, respectivamente, para a obtenção de Alcalinidade e de Acidez sem conhecer "a priori" o ponto final da titulação. A função F5BC permite também a determinação da Primeira e da Segunda Constante Aparente de Dissociação do sistema carbonatado de águas salinas e de alta força iônica. Abstract in english Measurements of parameters expressed in terms of carbonic species such as Alkalinity and Acidity of saline waters do not analyze the influence of external parameters to the titration such as Total free and associated Carbonic Species Concentration, activity coefficient, ion pairing formation and Res [...] idual Liquid Junction Potential in pH measurements. This paper shows the development of F5BC titration function based on the titrations developed by Gran (1952) for the carbonate system of natural waters. For practical use, samples of saline waters from Pocinhos reservoir in Paraiba were submitted to titration and linear regression analysis. Results showed that F5BC involves F1x and F2x Gran functions determination, respectively, for Alkalinity and Acidity calculations without knowing "a priori" the endpoint of the titration. F5BC also allows the determination of the First and Second Apparent Dissociation Constant of the carbonate system of saline and high ionic strength waters.

  14. Electronic structure and reactivity in water splitting of the iron oxide dimers and their hexacarbonyls: A density functional study

    International Nuclear Information System (INIS)

    The iron oxide dimers (FeO)2 and their peroxide isomers are studied with the B3LYP density functional as bare clusters and as hexacarbonyls. Among the bare clusters the planar four-member ring structures are more stable than the non-planar ones and the rhombic dioxide Fe2O2 with antiferromagnetically ordered electrons on iron centers is the global minimum. Water adsorption on the bare diiron dioxide is exothermic, but dissociation does not occur. Carbonylation favors a non-planar Fe2O2 ring for both the dioxides and the peroxides and high electron density at the Fe centers is induced, evidenced by the natural charge distribution, the high proton affinity, and the values of global electronegativity and hardness. The iron dioxide hexacarbonyl Fe2O2(CO)6 is diamagnetic in the state of the global minimum. It is separated from the next low-lying triplet state by a small energy gap of 0.22 eV. Time-dependent density functional theory methods were applied to examine electron excitations from the ground state to the low-lying triplet states in the hexacarbonyls and their adsorption complexes with water. Singlet-to-triplet state excitations occur via ligand-to-metal charge transfer in the hexacarbonyls; in the adsorption complexes excitations from the oxygen lone pairs to the adsorption center also occur and they appear in the IR-visible region. The lowest energy singlet and triplet state reaction paths for water splitting were followed. On the singlet potential energy surface (PES), water splitting is spontaneous, while for the triplet PES an activation barrier of 14.1 kJ mol?1 was determined

  15. Highly permeable polymeric membranes based on the incorporation of the functional water channel protein Aquaporin Z

    OpenAIRE

    Kumar, Manish; Grzelakowski, Mariusz; Zilles, Julie; Clark, Mark; Meier, Wolfgang

    2007-01-01

    The permeability and solute transport characteristics of amphiphilic triblock-polymer vesicles containing the bacterial water-channel protein Aquaporin Z (AqpZ) were investigated. The vesicles were made of a block copolymer with symmetric poly-(2-methyloxazoline)-poly-(dimethylsiloxane)-poly-(2-methyloxazoline) (PMOXA15-PDMS110-PMOXA15) repeat units. Light-scattering measurements on pure polymer vesicles subject to an outwardly directed salt gradient in a stopped-flow apparatus indicated that...

  16. Stimulatory Effects of Balanced Deep Sea Water on Mitochondrial Biogenesis and Function

    OpenAIRE

    Ha, Byung Geun; Park, Jung-Eun; Cho, Hyun-Jung; Shon, Yun Hee

    2015-01-01

    The worldwide prevalence of metabolic diseases, including obesity and diabetes, is increasing. Mitochondrial dysfunction is recognized as a core feature of these diseases. Emerging evidence also suggests that defects in mitochondrial biogenesis, number, morphology, fusion, and fission, contribute to the development and progression of metabolic diseases. Our previous studies revealed that balanced deep-sea water (BDSW) has potential as a treatment for diabetes and obesity. In this study, we ai...

  17. Water transport and functional dynamics of aquaporins in osmoregulatory organs of fishes

    DEFF Research Database (Denmark)

    Madsen, Steffen S; Engelund, Morten B; Cutler, Christopher P

    2015-01-01

    Aquaporins play distinct roles for water transport in fishes as they do in mammals-both at the cellular, organ, and organismal levels. However, with over 32,000 known species of fishes inhabiting almost every aquatic environment, from tidal pools, small mountain streams, to the oceans and extreme salty desert lakes, the challenge to obtain consensus as well as specific knowledge about aquaporin physiology in these vertebrate clades is overwhelming. Because the integumental surfaces of these anim...

  18. Water Extract of Dryopteris crassirhizoma Attenuates Bone Loss by Suppressing Osteoclast Differentiation and Function

    OpenAIRE

    Hyunil Ha; Ki-Shuk Shim; Taesoo Kim; Hyosun An; Jin Yeul Ma

    2013-01-01

    The rhizome of Dryopteris crassirhizoma has been used as a traditional herbal medicine for treating various inflammatory and infectious diseases such as tapeworm infestation and mumps. In the present study, we investigated the bone protective effect of water extract of the rhizome of Dryopteris crassirhizoma (WEDC). We found that WEDC inhibits osteoclast differentiation via directly acting on osteoclast precursors. In osteoclast precursors, WEDC inhibited receptor activator of nuclear factor-...

  19. Sound speed in water-saturated glass beads as a function of frequency and porosity

    OpenAIRE

    Argo IV, Theodore F.; Guild, Matthew D.; Wilson, Preston S.; Schröter, Matthias; Radin, Charles; Swinney, Harry L.

    2009-01-01

    Sound propagation in water-saturated granular sediments is known to depend on the sediment porosity, but few data in the literature address both the frequency and porosity dependency. To begin to address this deficiency, a fluidized bed technique was used to control the porosity of an artificial sediment composed of glass spheres of 265 {\\mu}m diameter. Time-of-flight measurements and the Fourier phase technique were utilized to determine the sound speed for frequencies from...

  20. Subcritical water extraction of nutraceuticals with antioxidant activity from oregano. Chemical and functional characterization

    OpenAIRE

    Rodríguez Meizoso, Irene; Marin, Francisco R.; Herrero, Miguel; Señorans, F. Javier; Reglero, Guillermo; Cifuentes, Alejandro; Ibáñez, Elena

    2006-01-01

    In the present work, oregano leaves (Origanum vulgare L.) are explored as natural source of nutraceuticals with antioxidant activity. To do this, subcritical water extraction (SWE), a new environmentally friendly technique, is employed as extraction procedure and HPLC coupled to DAD is used for the chemical characterization of the extracts. Moreover, the radical scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and the determination of the total phenolic content (measured with t...

  1. Enzyme-inspired functional surfactant for aerobic oxidation of activated alcohols to aldehydes in water

    KAUST Repository

    Chen, Batian

    2015-02-06

    We describe an enzyme-inspired catalytic system based on a rationally designed multifunctional amphiphile. The resulting micelles feature metal-binding sites and stable free radical moieties as well as fluorous pockets that attract and preconcentrate molecular oxygen. In the presence of copper ions, the micelles effect chemoselective aerobic alcohol oxidation under ambient conditions in water, a transformation that is challenging to achieve nonenzymatically.

  2. Hemimicelle capped functionalized carbon nanotubes-based nanosized solid-phase extraction of arsenic from environmental water samples

    International Nuclear Information System (INIS)

    The end functionalization of CNTs can introduce oxygen-containing negatively functional groups such as -COOH, -OH, or -C=O on their surface site. If cationic surfactant such as cetyltrimethylammonium chloride (CTAC) was added to the functionalized CNTs, then interactions such as hydrophobic and ionic may lead to formation of hemimicelle/admicelle aggregates on the CNTs, a new kind of adsorbents, namely, the hemimicelle capped CMMWCNTs, is obtained. The application of the hemimicelle capped carbon nanotubes-based nanosized solid-phase extraction (SPE) adsorbents in environmental analysis is reported for the first time using arsenic as model target. The effect of adsorption and desorption conditions for arsenic including the amount of surfactant, initial pH of sample solution, the ultrasonic time of sample solution, the amount of electrolyte, flow rate, eluent and its amount were investigated and optimized prior to its determination by atomic fluorescence spectrophotometry (AFS). Arsenic can be quantitatively retained on the hemimicelle capped CMMWCNTs at pH 5-6 from sample volume up to 500 mL and then eluted completely with 2 mol L-1 HNO3 in the presence of 10 mg L-1 CTAC. The method detection limit for arsenic determination with AFS detection was 2 ng L-1, and the relative standard deviation (RSD, n = 11) was 5.3% at the 0.5 ?g L-1 level. The recoveries of arsenic in the spiked environmental water samples ranged from 94% to 104.29% with 500 mL of water sample. The proposed method has been applied successfully to the analysis of arsenic in aqueous environmental samples, which demonstrates the hemimicelle capped CMMWCNTs can be an excellent SPE adsorbents for arsenic pretreatment and enrichment from real water samples

  3. Functionalized paper-A readily accessible adsorbent for removal of dissolved heavy metal salts and nanoparticles from water.

    Science.gov (United States)

    Setyono, Daisy; Valiyaveettil, Suresh

    2016-01-25

    Paper, a readily available renewable resource, comprises of interwoven cellulosic fibers, which can be functionalized to develop interesting low-cost adsorbent material for water purification. In this study, polyethyleneimine (PEI)-functionalized paper was used for the removal of hazardous pollutants such as Au and Ag nanoparticles, Cr(VI) anions, Ni(2+), Cd(2+), and Cu(2+) cations from spiked water samples. Compared to untreated paper, the PEI-coated paper showed significant improvement in adsorption capacities toward the pollutants investigated in this study. Kinetics, isotherm models, pH, and desorption studies were carried out to study the adsorption mechanism of pollutants on the adsorbent surface. Adsorption of pollutants was better described by pseudo-second order kinetics and Langmuir isotherm model. Maximum adsorption of anionic pollutants was achieved at pH 5 while that of cations was at pH>6. Overall, the PEI-functionalized paper showed interesting Langmuir adsorption capacities for heavy metal ions such as Cr(VI) (68mg/g), Ni(2+) (208mg/g), Cd(2+) (370mg/g), and Cu(2+) (435mg/g) ions at neutral pH. In addition, the modified paper was also used to remove Ag-citrate (79mg/g), Ag-PVP (46mg/g), Au-citrate (30mg/g), Au-PVP (17mg/g) nanoparticles from water. Desorption of NPs from the adsorbent was done by washing with 2M HCl or thiourea solution, while heavy metal ions were desorbed using 1M NaOH or HNO3 solution. The modified paper retained its extraction efficiencies upon desorption of pollutants. PMID:26452090

  4. Why cold water delays the onset of vestibular vertigo-An functional MRI study

    International Nuclear Information System (INIS)

    The mechanism of vertigo is unclear. Generally, the peak time or the latency of blood oxygenation level dependent (BOLD) effect is about 6 s. However, clinically, the latency of vertigo or nystagmus induced by caloric stimulations is much longer than 6 s, commonly about 30 s induced by water of 30 deg. C or 44 deg. C. We hypothesize that there is an inhibitive power or mechanism for the occurrence of vestibular vertigo, since it is an unpleasant feeling. The caloric test was performed in healthy volunteers during the BOLD fMRI scanning. The overlaid results of statistical parametric mapping (SPM) showed that three brain regions showed neural activation during vestibular dizziness while deactivation occurred in response to cold water simulation: (1) supplementary motor area (SMA); (2) middle temporal area/medial superior temporal area (MT/MST); (3) visual association area (BA19). The time course of the regions further demonstrated that the signal decreased during the cold-water stimulation and increased during the period of vertigo. We therefore further hypothesize that there may be two forces for the production of vertigo: inhibitory power (IP) and promotive power (PP). The delayed onset of vertigo was the result of the interaction between IP and PP. All of our findings, for the first time, suggested such an original mechanism of vertigo

  5. Why cold water delays the onset of vestibular vertigo-An functional MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhi [Department of Radiology, Beijing Hospital, No. 1 Dahua Road Dongdan, Beijing 100730 (China)], E-mail: zhiwang76@gmail.com; Chen Min [Department of Radiology, Beijing Hospital, No. 1 Dahua Road Dongdan, Beijing 100730 (China); Gong Xia; Huang Weining [Department of E.N.T., Beijing Hospital, No. 1 Dahua Road Dongdan, Beijing 100730 (China); Xu Liang [Department of Radiology, Beijing Hospital, No. 1 Dahua Road Dongdan, Beijing 100730 (China); Zhou Cheng [Department of Radiology, Beijing Hospital, No. 1 Dahua Road Dongdan, Beijing 100730 (China)], E-mail: chengzhou2000@yahoo.com

    2008-09-15

    The mechanism of vertigo is unclear. Generally, the peak time or the latency of blood oxygenation level dependent (BOLD) effect is about 6 s. However, clinically, the latency of vertigo or nystagmus induced by caloric stimulations is much longer than 6 s, commonly about 30 s induced by water of 30 deg. C or 44 deg. C. We hypothesize that there is an inhibitive power or mechanism for the occurrence of vestibular vertigo, since it is an unpleasant feeling. The caloric test was performed in healthy volunteers during the BOLD fMRI scanning. The overlaid results of statistical parametric mapping (SPM) showed that three brain regions showed neural activation during vestibular dizziness while deactivation occurred in response to cold water simulation: (1) supplementary motor area (SMA); (2) middle temporal area/medial superior temporal area (MT/MST); (3) visual association area (BA19). The time course of the regions further demonstrated that the signal decreased during the cold-water stimulation and increased during the period of vertigo. We therefore further hypothesize that there may be two forces for the production of vertigo: inhibitory power (IP) and promotive power (PP). The delayed onset of vertigo was the result of the interaction between IP and PP. All of our findings, for the first time, suggested such an original mechanism of vertigo.

  6. Functional issues and environmental qualification of digital protection systems of advanced light-water nuclear reactors

    International Nuclear Information System (INIS)

    Issues of obsolescence and lack of infrastructural support in (analog) spare parts, coupled with the potential benefits of digital systems, are driving the nuclear industry to retrofit analog instrumentation and control (I ampersand C) systems with digital and microprocessor-based systems. While these technologies have several advantages, their application to safety-related systems in nuclear power plants raises key issues relating to the systems' environmental qualification and functional reliability. To bound the problem of new I ampersand C system functionality and qualification, the authors focused this study on protection systems proposed for use in ALWRs. Specifically, both functional and environmental qualification issues for ALWR protection system I ampersand C were addressed by developing an environmental, functional, and aging data template for a protection division of each proposed ALWR design. By using information provided by manufacturers, environmental conditions and stressors to which I ampersand C equipment in reactor protection divisions may be subjected were identified. The resulting data were then compared to a similar template for an instrument string typically found in an analog protection division of a present-day nuclear power plant. The authors also identified fiber-optic transmission systems as technologies that are relatively new to the nuclear power plant environment and examined the failure modes and age-related degradation mechanisms of fiber-optic components and systems. One reason for the exercise of caution in the introduction of software into safety-critical systems is the potential for common-cause failure due to the software. This study, however, approaches the functionality problem from a systems point of view. System malfunction scenarios are postulated to illustrate the fact that, when dealing with the performance of the overall integrated system, the real issues are functionality and fault tolerance, not hardware vs. software

  7. Functional issues and environmental qualification of digital protection systems of advanced light-water nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Korsah, K.; Clark, R.L.; Wood, R.T. [Oak Ridge National Lab., TN (United States)

    1994-04-01

    Issues of obsolescence and lack of infrastructural support in (analog) spare parts, coupled with the potential benefits of digital systems, are driving the nuclear industry to retrofit analog instrumentation and control (I&C) systems with digital and microprocessor-based systems. While these technologies have several advantages, their application to safety-related systems in nuclear power plants raises key issues relating to the systems` environmental qualification and functional reliability. To bound the problem of new I&C system functionality and qualification, the authors focused this study on protection systems proposed for use in ALWRs. Specifically, both functional and environmental qualification issues for ALWR protection system I&C were addressed by developing an environmental, functional, and aging data template for a protection division of each proposed ALWR design. By using information provided by manufacturers, environmental conditions and stressors to which I&C equipment in reactor protection divisions may be subjected were identified. The resulting data were then compared to a similar template for an instrument string typically found in an analog protection division of a present-day nuclear power plant. The authors also identified fiber-optic transmission systems as technologies that are relatively new to the nuclear power plant environment and examined the failure modes and age-related degradation mechanisms of fiber-optic components and systems. One reason for the exercise of caution in the introduction of software into safety-critical systems is the potential for common-cause failure due to the software. This study, however, approaches the functionality problem from a systems point of view. System malfunction scenarios are postulated to illustrate the fact that, when dealing with the performance of the overall integrated system, the real issues are functionality and fault tolerance, not hardware vs. software.

  8. Variable reluctance displacement transducer temperature compensated to 6500F

    International Nuclear Information System (INIS)

    In pressurized water reactor tests, compact instruments for accurate measurement of small displacements in a 6500F environment are often required. In the case of blowdown tests such as the Loss of Fluid Test (LOFT) or Semiscale computer code development tests, not only is the initial environment water at 6500F and 2200 psi but it undergoes a severe transient due to depressurization. Since the LOFT and Semiscale tests are run just for the purpose of obtaining data during the depressurization, instruments used to obtain the data must not give false outputs induced by the change in environment. A LOFT rho v2 probe and a Semiscale drag disk are described. Each utilizes a variable reluctance transducer (VRT) for indication of the drag-disk location and a torsion bar for drag-disk restoring force. The VRT, in addition to being thermally gain and null offset stable, is fabricated from materials known to be resistant to large nuclear radiation levels and has successfully passed a fast neutron radiation test of 2.7 x 1017 nvt without failure

  9. Relativistic Lagrangian displacement field and tensor perturbations

    CERN Document Server

    Rampf, Cornelius

    2014-01-01

    We investigate the purely spatial Lagrangian coordinate transformation from the Lagrangian to the fundamental Eulerian frame. We demonstrate three techniques for extracting the relativistic displacement field from a given solution in the Lagrangian frame. These techniques are (a) from defining a local set of Eulerian coordinates embedded into the Lagrangian frame; (b) from performing a specific gauge transformation; and (c) from a fully non-perturbative approach based on the ADM split. The latter approach shows that this decomposition is not tied to a specific perturbative formulation for the solution of the Einstein equations. Rather, it can be defined at the level of the non-perturbative coordinate change from the Lagrangian to the Eulerian description. Studying such different techniques is useful because it allows us to compare and develop further the various approximation techniques available in the Lagrangian formulation. We find that one has to solve for gravitational waves in the relativistic analysis,...

  10. An Alternative to Maxwell's Displacement Current

    CERN Document Server

    Wolsky, Alan M

    2014-01-01

    Though sufficient for local conservation of charge, we show that Maxwells displacement current is not necessary. An alternative to the Ampere Maxwell equation is exhibited and the alternative s electric and magnetic fields and scalar and vector potentials are expressed in terms of the charge and current densities. The alternative describes a theory in which action is instantaneous and so may provide a good approximation to Maxwells equations where and when the finite speed of light can be neglected. The result is reminiscent of the Darwin approximation which arose from the study classical charged point particles to order (v/c)2 in the Lagrangian. Unlike Darwin, this approach does not depend on the constitution of the electric current. Instead, this approach grows from a straightforward revision of the Ampere Equation which revision enforces the local conservation of charge.

  11. Searching for displaced Higgs boson decays

    Science.gov (United States)

    Csáki, Csaba; Kuflik, Eric; Lombardo, Salvator; Slone, Oren

    2015-10-01

    We study a simplified model of the Standard Model (SM) Higgs boson decaying to a degenerate pair of scalars which travel a macroscopic distance before decaying to SM particles. This is the leading signal for many well-motivated solutions to the hierarchy problem that do not propose additional light colored particles. Bounds for displaced Higgs boson decays below 10 cm are found by recasting existing tracker searches from Run I. New tracker search strategies, sensitive to the characteristics of these models and similar decays, are proposed with sensitivities projected for Run II at ?{s }=13 TeV . With 20 fb-1 of data, we find that Higgs branching ratios down to 2 ×1 0-4 can be probed for centimeter decay lengths.

  12. Axial flow positive displacement worm compressor

    Science.gov (United States)

    Murrow, Kurt David (Inventor); Giffin, Rollin George (Inventor); Fakunle, Oladapo (Inventor)

    2010-01-01

    An axial flow positive displacement compressor has an inlet axially spaced apart and upstream from an outlet. Inner and outer bodies have offset inner and outer axes extend from the inlet to the outlet through first and second sections of a compressor assembly in serial downstream flow relationship. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes respectively. The inner and outer helical blades extend radially outwardly and inwardly respectively. The helical blades have first and second twist slopes in the first and second sections respectively. The first twist slopes are less than the second twist slopes. An engine including the compressor has in downstream serial flow relationship from the compressor a combustor and a high pressure turbine drivingly connected to the compressor by a high pressure shaft.

  13. Centrifugal deterministic lateral displacement separation system

    CERN Document Server

    Jiang, Mingliang; Drazer, German

    2015-01-01

    This work investigates the migration of spherical particles of different sizes in a centrifuge-driven deterministic lateral displacement (c-DLD) device. Specifically, we use a scaled-up model to study the motion of suspended particles through a square array of cylindrical posts under the action of centrifugation. Experiments show that separation of particles by size is possible depending on the orientation of the driving acceleration with respect to the array of posts (forcing angle). We focus on the fractionation of binary suspensions and measure the separation resolution at the outlet of the device for different forcing angles. We found excellent resolution at intermediate forcing angles, when large particles are locked to move at small migration angles but smaller particles follow the forcing angle more closely. Finally, we show that reducing the initial concentration (number) of particles, approaching the dilute limit of single particles, leads to increased resolution in the separation.

  14. Computer simulation of displacement cascades in ?-zirconium

    International Nuclear Information System (INIS)

    The damage produced in ?-zirconium at 100 K by displacement cascades with energy up to 20 keV has been investigated by MD simulations. In agreement with modelling of fcc and bcc metals, the defect production efficiency in zirconium is well below the NRT estimate. The number and size of clusters, both vacancy and interstitial, are increased by increasing PKA energy, and clusters containing up to 25 interstitials and 30 vacancies were formed by 20 keV cascades. Most interstitial clusters have dislocation character with perfect Burgers vectors of the form 1/3, but a few metastable clusters are formed and are persistent over the timescale of MD simulations. Collapse of the 30-vacancy cluster to a faulted loop on the prism plane was found to occur over a period of more than 100 ps

  15. Can Monkeys (Macaca mulatta) Represent Invisible Displacement?

    Science.gov (United States)

    Filion, Christine M.; Washburn, David A.; Gulledge, Jonathan P.

    1996-01-01

    Four experiments were conducted to assess whether or not rhesus macaques (Macaca mulatta) could represent the unperceived movements of a stimulus. Subjects were tested on 2 computerized tasks, HOLE (monkeys) and LASER (humans and monkeys), in which subjects needed to chase or shoot at, respectively, a moving target that either remained visible or became invisible for a portion of its path of movement. Response patterns were analyzed and compared between target-visible and target-invisible conditions. Results of Experiments 1, 2, and 3 demonstrated that the monkeys are capable of extrapolating movement. That this extrapolation involved internal representation of the target's invisible movement was suggested but not confirmed. Experiment 4, however, demonstrated that the monkeys are capable of representing the invisible displacements of a stimulus.

  16. Displaced fracture through the anterior atlantal synchondrosis

    Energy Technology Data Exchange (ETDEWEB)

    Thakar, Chrishan; Allibone, James [Royal National Orthopaedic Hospital NHS Trust, Department of Spinal Deformity, Stanmore, Middlesex (United Kingdom); Harish, Srinivasan [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom); Saifuddin, Asif [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom); University College, The Institute of Orthopaedics and Musculoskeletal Sciences, London (United Kingdom)

    2005-09-01

    In the acute setting, accurate radiological interpretation of paediatric cervical spine trauma can be difficult due to a combination of normal variants and presence of multiple synchondroses. We present a rare case of a fracture through the anterior atlantal synchondrosis in a paediatric spine. A five-year-old boy, who fell backwards onto the top of his head while swinging across on a monkey bar frame, presented with neck pain, cervical muscle spasm and decreased right lateral rotation and extension of his neck. Computed tomography showed a displaced diastatic fracture through right anterior atlantal synchondrosis. There are only 12 cases of paediatric C1 fractures reported in the world literature. The importance of considering this diagnosis in the appropriate clinical setting, and the normal variants in the paediatric atlas that can cause diagnostic dilemma to the interpreting radiologist, are discussed in this case report. (orig.)

  17. Consumption of water containing over 3.5 mg of dissolved hydrogen could improve vascular endothelial function

    Directory of Open Access Journals (Sweden)

    Sakai T

    2014-10-01

    Full Text Available Takaaki Sakai,1 Bunpei Sato,2 Koji Hara,3 Yuichi Hara,3 Yuji Naritomi,3 Samon Koyanagi,1 Hiroshi Hara,3 Tetsuhiko Nagao,4 Toru Ishibashi51Department of Cardiology, Haradoi Hospital, Fukuoka, Japan; 2MiZ Company Limited, Fujisawa, Kanagawa, Japan; 3Department of Internal Medicine, Haradoi Hospital, Fukuoka, Japan; 4Midorino Clinic, Aoba, Higashi-ku, Fukuoka, Japan; 5Department of Rheumatology and Orthopedic Surgery, Haradoi Hospital, Fukuoka, Japan Background: The redox imbalance between nitric oxide and superoxide generated in the endothelium is thought to play a pivotal role in the development of endothelial dysfunction. A third reactive oxygen species (ROS, H2O2, is known to have both beneficial and detrimental effects on the vasculature. Nonetheless, the influence of the hydroxyl radical, a byproduct of H2O2 decay, is unclear, and there is no direct evidence that the hydroxyl radical impairs endothelial function in conduit arteries. Molecular hydrogen (H2 neutralizes detrimental ROS, especially the hydroxyl radical. Objectives: To assess the influence of the hydroxyl radical on the endothelium and to confirm that a gaseous antioxidant, H2, can be a useful modulator of blood vessel function. Methods: The efficacy of water containing a high concentration of H2 was tested by measuring flow-mediated dilation (FMD of the brachial artery (BA. The subjects were randomly divided into two groups: the high-H2 group, who drank high-H2 water containing 7 ppm H2 (3.5 mg H2 in 500 mL water; and the placebo group. Endothelial function was evaluated by measuring the FMD of the BA. After measurement of diameter of the BA and FMD at baseline, volunteers drank the high-H2 water or placebo water immediately and with a 30-minute interval; FMD was compared to baseline. Results: FMD increased in the high-H2 group (eight males; eight females from 6.80%±1.96% to 7.64%±1.68% (mean ± standard deviation and decreased from 8.07%±2.41% to 6.87%±2.94% in the placebo group (ten males; eight females. The ratio to the baseline in the changes of FMD showed significant improvement (P<0.05 in the high-H2 group compared to the placebo group. Conclusion: H2 may protect the vasculature from shear stress-derived detrimental ROS, such as the hydroxyl radical, by maintaining the nitric oxide-mediated vasomotor response. Keywords: flow-mediated dilation, reactive oxygen species, molecular hydrogen, hydroxyl radical, 5–7 ppm, peroxynitrite

  18. Optical chemosensor for the detection of cyanide in water based on ethyl(hydroxyethyl)cellulose functionalized with Brooker's merocyanine.

    Science.gov (United States)

    Nandi, Leandro G; Nicoleti, Celso R; Bellettini, Ismael C; Machado, Vanderlei G

    2014-05-20

    Ethyl(hydroxyethyl)cellulose was functionalized with Brooker's merocyanine. The modified polymer was easily transformed in a film, which could be used as a highly selective chromogenic and fluorogenic chemosensor for the detection of cyanide in water, with detection limits of 1.9 × 10(-5) and 1.0 × 10(-7) mol L(-1). The film was successfully applied to the detection of cyanide in cassava (Manihot esculenta Crantz) roots, which are a well-known source of endogenous biological cyanide. PMID:24805864

  19. Radioactive probe studies of coordination modes of heavy metal ions from natural waters to functionalized magnetic nanoparticles

    CERN Multimedia

    Carvalho soares, J; Lopes, C; Araujo, J

    We propose to use PAC, Perturbed Angular Correlations, to study the local environment of ionic species (Hg$^{2+}$, Cd$^{2+}$) coordinated on functionalized magnetic nanoparticles. Studies include the analysis of different nanoparticles sizes (30-100nm), and the monitoring of time/steps dependence of the coordination of those cations at the nanoparticles surfaces. Combined with theoretical calculations, the obtained data will support the understanding of local coordination modes, which is essential to help to improve methods of magnetically assisted separation of such hazardous contaminants from water.

  20. Approaching the Quantum Limits of Displacement Detection

    Science.gov (United States)

    Teufel, John

    2013-03-01

    While high quality factor mechanical resonators (such as cantilevers and membranes) are routinely used as exquisite sensors, only recently are these engineered devices encountering the fundamental limits and opportunities afforded by quantum mechanics. The standard quantum limit of displacement detection requires a balance between the measurement imprecision and momentum imparted on the object of interest. One promising measurement scheme for achieving, and possibly surpassing, these quantum limits of measurement is that of cavity optomechanics--an architecture in which a mechanical resonator modulates the frequency of a high frequency electromagnetic resonance. Ideally, the quantized nature of the measurement photons will impart backaction in the form of radiation pressure shot noise, but observation of this quantum effect in macroscopic mechanical resonators has proven experimental difficult due to the relatively weak forces of the light. We realize a microwave cavity ``opto'' -mechanical system by incorporating a freely-suspended membrane in a superconducting microwave resonant circuit, which simultaneously exhibits high quality factor electrical and mechanical modes. The relatively large electomechanical coupling has led to experimental observation of the strong coupling regime as well as sideband cooling of the mechanical mode to its quantum ground state. I will present recent experiments of similar circuits in which the displacement sensitivity goes beyond that at the standard quantum limit by several orders of magnitude. These measurements also clearly show the fundamental trade-off between measurement imprecision and backaction. We observe the radiation pressure shot noise of the microwave photons and show that it can completely overwhelm the classical, thermal motion of the membrane.

  1. Relativistic Lagrangian displacement field and tensor perturbations

    Science.gov (United States)

    Rampf, Cornelius; Wiegand, Alexander

    2014-12-01

    We investigate the purely spatial Lagrangian coordinate transformation from the Lagrangian to the basic Eulerian frame. We demonstrate three techniques for extracting the relativistic displacement field from a given solution in the Lagrangian frame. These techniques are (a) from defining a local set of Eulerian coordinates embedded into the Lagrangian frame; (b) from performing a specific gauge transformation; and (c) from a fully nonperturbative approach based on the Arnowitt-Deser-Misner (ADM) split. The latter approach shows that this decomposition is not tied to a specific perturbative formulation for the solution of the Einstein equations. Rather, it can be defined at the level of the nonperturbative coordinate change from the Lagrangian to the Eulerian description. Studying such different techniques is useful because it allows us to compare and develop further the various approximation techniques available in the Lagrangian formulation. We find that one has to solve the gravitational wave equation in the relativistic analysis, otherwise the corresponding Newtonian limit will necessarily contain spurious nonpropagating tensor artifacts at second order in the Eulerian frame. We also derive the magnetic part of the Weyl tensor in the Lagrangian frame, and find that it is not only excited by gravitational waves but also by tensor perturbations which are induced through the nonlinear frame dragging. We apply our findings to calculate for the first time the relativistic displacement field, up to second order, for a ? CDM Universe in the presence of a local primordial non-Gaussian component. Finally, we also comment on recent claims about whether mass conservation in the Lagrangian frame is violated.

  2. Connecting localized DNA strand displacement reactions

    Science.gov (United States)

    Mullor Ruiz, Ismael; Arbona, Jean-Michel; Lad, Amitkumar; Mendoza, Oscar; Aimé, Jean-Pierre; Elezgaray, Juan

    2015-07-01

    Logic circuits based on DNA strand displacement reactions have been shown to be versatile enough to compute the square root of four-bit numbers. The implementation of these circuits as a set of bulk reactions faces difficulties which include leaky reactions and intrinsically slow, diffusion-limited reaction rates. In this paper, we consider simple examples of these circuits when they are attached to platforms (DNA origamis). As expected, constraining distances between DNA strands leads to faster reaction rates. However, it also induces side-effects that are not detectable in the solution-phase version of this circuitry. Appropriate design of the system, including protection and asymmetry between input and fuel strands, leads to a reproducible behaviour, at least one order of magnitude faster than the one observed under bulk conditions.Logic circuits based on DNA strand displacement reactions have been shown to be versatile enough to compute the square root of four-bit numbers. The implementation of these circuits as a set of bulk reactions faces difficulties which include leaky reactions and intrinsically slow, diffusion-limited reaction rates. In this paper, we consider simple examples of these circuits when they are attached to platforms (DNA origamis). As expected, constraining distances between DNA strands leads to faster reaction rates. However, it also induces side-effects that are not detectable in the solution-phase version of this circuitry. Appropriate design of the system, including protection and asymmetry between input and fuel strands, leads to a reproducible behaviour, at least one order of magnitude faster than the one observed under bulk conditions. Electronic supplementary information (ESI) available. See DOI: 10.1039/C5NR02434J

  3. Photosynthetic metabolism and quality of Eugenia pyriformis Cambess. seedlings on substrate function and water levels

    Scientific Electronic Library Online (English)

    SILVANA P.Q., SCALON; TATIANE S., JEROMINI; ROSILDA M., MUSSURY; DAIANE M., DRESCH.

    2014-12-01

    Full Text Available Objetivou-se no presente trabalho avaliar a qualidade e o metabolismo fotossintético das mudas de uvaia (Eugenia pyriformis Cambess.) em diferentes substratos e regimes hídricos. A semeadura foi realizada em tubetes de 50 x 190 mm nos seguintes substratos: Areia (A), Latossolo + areia (L + A) (1:1), [...] Latossolo + areia + cama de frango semidecomposta (L + A1 + CF) (1:1:0,5), Latossolo + areia + cama de frango semidecomposta (L + A2 + CF) (1:2:0,5), Latossolo + Bioplant® (L + B) (1:1) e os níveis de irrigação avaliados foram 50, 75 e 100% da capacidade de retenção de água. Aos 60, 90, 120 e 150 dias de idade as mudas foram avaliadas quanto ao índice de clorofila; a área foliar (cm2) e o índice de qualidade de Dickson (IQD) e aos 150 dias de idade foram avaliadas a concentração interna de carbono (mol m–2 s–1), condutância estomática (mol m–2 s–1), taxa de transpiração (mmol m–2 s–1), fotossíntese (µmol m–2 s–1) e eficiência no uso da água (µmol de CO2 / mmol de H2O). Até os 150 dias de idade, as mudas apresentaram maior qualidade e metabolismo fotossintético quando cultivadas com substratos contendo Latossolo + areia + cama de frango nas duas variações avaliadas e na capacidade de retenção de água de 50 %. Abstract in english The aim of this research was to evaluate the quality and photosynthetic metabolism of “uvaia” seedlings (Eugenia pyriformis Cambess.) on different substrates and water regimes. The seeds were sown in tubes of 50 x 190 mm in the following substrates: Sand (S), Latosol + Sand (L + S) (1:1), Latosol + [...] Sand + Semi Decomposed Poultry Litter (L + S1 + PL) ( 1:1:0.5), Latosol + Sand + Semi Decomposed Poultry Litter (L + S2 + PL) (1:2:0.5), Latosol + Bioplant® (L + B) (1:1), and the water levels assessed were 50, 75 and 100% of water retention capacity. At 60, 90, 120 and 150 days the seedlings were evaluated according to their chlorophyll index, leaf area (cm2) and Dickson Quality Index (DQI) and at 150 days their internal concentration of carbon (mol m–2 s–1), stomatal conductance (mol m–2 s–1), transpiration rate (mmol m–2 s–1), photosynthesis (µmol m–2 s–1) and efficiency of water use (µmol de CO2 / mmol de H2O). Until their 150th days, the seedlings had higher quality and photosynthetic metabolism when cultured with substrates containing latosol + sand + poultry litter on the two variations assessed and water retention capacity of 50%.

  4. Displacements Prediction in Double-Arch Dam Rock Abutment Using SPSS Software Based on Extensometer Readings Case study: Karun 4 Concrete Dam, Iran

    Directory of Open Access Journals (Sweden)

    Hadi kamali Bandpey

    2012-11-01

    Full Text Available In this study we present a method for Displacements Prediction in Double-Arch Dam Rock Abutment Using SPSS Software Based on Extensometer Readings. Displacement in dams is the most tangible and important parameter which could be crucial in their safety. Different elevation displacements are yielded by various loadings and the thrust force imposed on foundation and abutment. Most concrete dams are constructed on stone foundations. Displacements in foundation and abutment are measured by extensometers. Karun 4 Concrete dam is designed with 11 galleries, from elevation 1016 to 802 m, in the order from top elevation (dam crest elevation 1032 to the bottom elevation (dam foundation elevation 806 within the dam body. As a whole, 19 extensometers in the left bank, 17 in the right, and one more in the middle are implemented in the dam. Karun 4 dam has already been impounded with water up to the elevation 1003. Displacements in Karun 4 are recorded by extensometers whence water was leveled in 7 elevations 943.68, 953.36, 973.55, 983.28, 993.17, 1003.13. In this study, using SPSS we have tried to predict the displacements for a situation in which water will be elevated to the elevations 1013, 1023, 1032 in the future for elevations which are equipped with anchor. The most predicted displacement pertaining to the left bank when water was leveled to the elevation 1013, was 3.65 mms by R2 = 0.9997 for the implemented anchor. Proceeding further, as water is leveled to the elevations 1023 and 1033, the most predicted displacement respectively would be 4.31 and 5.66 by R2 = 0.9941; and is related to the anchor implemented in the elevation 936.05. The most predicted displacement for the right bank is 5.9397, 7.2347 and 8.6877 mms by R2 = 0.9995 for the elevation 888.128 m.

  5. A Systematic Study of Chloride Ion Solvation in Water using van der Waals Inclusive Hybrid Density Functional Theory

    CERN Document Server

    Bankura, Arindam; DiStasio, Robert A; Swartz, Charles W; Klein, Michael L; Wu, Xifan

    2015-01-01

    In this work, the solvation and electronic structure of the aqueous chloride ion solution was investigated using Density Functional Theory (DFT) based \\textit{ab initio} molecular dynamics (AIMD). From an analysis of radial distribution functions, coordination numbers, and solvation structures, we found that exact exchange ($E_{\\rm xx}$) and non-local van der Waals (vdW) interactions effectively \\textit{weaken} the interactions between the Cl$^-$ ion and the first solvation shell. With a Cl-O coordination number in excellent agreement with experiment, we found that most configurations generated with vdW-inclusive hybrid DFT exhibit 6-fold coordinated distorted trigonal prism structures, which is indicative of a significantly disordered first solvation shell. By performing a series of band structure calculations on configurations generated from AIMD simulations with varying DFT potentials, we found that the solvated ion orbital energy levels (unlike the band structure of liquid water) strongly depend on the un...

  6. Effect of taxonomic resolution on ecological and palaeoecological inference - a test using testate amoeba water table depth transfer functions

    Science.gov (United States)

    Mitchell, Edward A. D.; Lamentowicz, Mariusz; Payne, Richard J.; Mazei, Yuri

    2014-05-01

    Sound taxonomy is a major requirement for quantitative environmental reconstruction using biological data. Transfer function performance should theoretically be expected to decrease with reduced taxonomic resolution. However for many groups of organisms taxonomy is imperfect and species level identification not always possible. We conducted numerical experiments on five testate amoeba water table (DWT) transfer function data sets. We sequentially reduced the number of taxonomic groups by successively merging morphologically similar species and removing inconspicuous species. We then assessed how these changes affected model performance and palaeoenvironmental reconstruction using two fossil data sets. Model performance decreased with decreasing taxonomic resolution, but this had only limited effects on patterns of inferred DWT, at least to detect major dry/wet shifts. Higher-resolution taxonomy may however still be useful to detect more subtle changes, or for reconstructed shifts to be significant.

  7. Percolation Line, Response Functions, and Voronoi Polyhedra Analysis in Supercritical Water.

    Czech Academy of Sciences Publication Activity Database

    Škvor, J.; Nezbeda, Ivo

    2012-01-01

    Ro?. 15, ?. 2 (2012), s. 23301. ISSN 1607-324X R&D Projects: GA AV ?R IAA200760905 Grant ostatní: GA UJEP(CZ) 53223–15–0010–01 Institutional support: RVO:67985858 Keywords : percolation line * response functions * widom lines Subject RIV: BJ - Thermodynamics Impact factor: 0.757, year: 2012

  8. Lateral vibration analysis of continuous bridges utilizing equal displacement rule

    Scientific Electronic Library Online (English)

    Biao, Wei; Ye, Xia; Weian, Liu.

    2014-01-01

    Full Text Available The application of equal displacement rule simplifies the evaluation of lateral displacement demand forSDOF system. For complex multi-degree-of-freedom (MDOF) structures such as continuous bridge systems, however, it requires more investigations. In this paper, a comprehensive parametric study of th [...] e ratio of maximum inelastic displacement to maximum elastic displacement for typical continuous bridges is performedto advance the application of equal displacement rule to MDOF systems. Particurlarly for the bridges with long periods, this adapted methodlogy is further simplified. It is concluded that equal displacement rule of MDOF is applicable to continuous bridges when the periods of the main modes are no less than the limiting period, which usually serves as an indication to the level of inelastic deformation for a bridge subjected to an earthquake.

  9. A study of water transport as a function of the micro-porous layer arrangement in PEMFCs

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Taeyoung; Lee, Seungjae; Park, Heekyung [Department of Civil and Environmental Engineering, KAIST, Guseong-dong, Yuseong-gu, Daejeon, 305-701 (Korea)

    2010-08-15

    Electrochemical losses as a function of the micro-porous layer (MPL) arrangement in Proton Exchange Membrane Fuel Cells (PEMFCs) are investigated by electrochemical impedance spectroscopy (EIS). Net water flux across the polymer membrane in PEMFCs is investigated for various arrangements of the MPL, namely with MPL on the cathode side alone, with MPL on both the cathode and the anode sides and without MPL. EIS and water transport are recorded for various operating conditions, such as the relative humidity of the hydrogen inlet and current density, in a PEMFC fed by fully-saturated air. The cell with an MPL on the cathode side alone has better performance than two other types of cells. Furthermore, the cell with an MPL on only the cathode increases the water flux from cathode to anode as compared to the cells with MPLs on both electrodes and cells without MPL. Oxygen-mass-transport resistances of cells in the presence of an MPL on the cathode are lower than the values for the other two cells, which indicates that the molar concentration of oxygen at the reaction surface of the catalyst layer is higher. This suggests that the MPL forces the liquid water from the cathode side to the anode side and decreases the liquid saturation in GDL at high current densities. Consequently, the MPL helps in maintaining the water content in the polymer membrane and decreases the cathode charge transfer and oxygen-mass transport resistances in PEMFCs, even when the hydrogen inlet has a low relative humidity. (author)

  10. Short-time distribution of particle displacements due to swimming microorganisms

    CERN Document Server

    Thiffeault, Jean-Luc

    2014-01-01

    The experiments of Leptos et al. [Phys. Rev. Lett. 103,198103 (2009)] show that the displacements of small particles affected by swimming microorganisms achieve a non-Gaussian distribution, which nevertheless scales diffusively. We use a simple model where the particles undergo repeated 'kicks' due to the swimmers to explain the shape of the distribution as a function of the volume fraction of swimmers. The net displacement is determined by the self-convolution of the drift function caused by one swimmer, and by a Poisson distribution for the frequency of interactions. The only adjustable parameter is the strength of the stresslet term in our spherical squirmer model. The effective diffusivity predicted by the model is consistent with the experiments, with no further parameter adjustments. The diffusive scaling appears to be due to the particular form of the drift function, and is not statistical in origin. The model also suggests that the scaling disappears for longer times, when the swimmers undergo signifi...

  11. Surgical removal of dental implants displaced into the maxillary sinus

    OpenAIRE

    Chrcanovic Ramos Bruno; Custódio Neto Luís Antônio

    2009-01-01

    The accidental displacement of roots, endodontic materials and dental implants into the maxillary sinus are relatively common complications in dental clinical practice. The purpose of this study is to present four cases of displaced dental implant into maxillary sinus, their treatment as well as the prevention of this condition. There are three different major approaches to remove materials displaced into the maxillary sinus: suction from the socket of an extracted tooth, the classical open s...

  12. In-plane displacement measurement in vortex metrology

    OpenAIRE

    Angel-Toro, Luciano; Sierra-Sosa, Daniel; Tebaldi, Myrian; Bolognini, N??stor

    2013-01-01

    Recently we proposed an alternative method of displacement analysis in vortex metrology, based on the application of the Fourier optics techniques, that is suitable for an intermediate range of displacement measurements ranging below the resolution of speckle photography and above that of the conventional vortex metrology. However, for smaller displacements, we introduce an approach to perform the Fourier analysis from vortex networks. In this work, we present an enhanced method for measuring...

  13. The Effect of Job Displacement on Subsequent Health

    OpenAIRE

    Gallo, William T.; Bradley, Elizabeth H; Kasl, Stanislav V.

    2001-01-01

    Using data from the 1994-1996 waves of the German Socio-Economic Panel (GSOEP), this prospective longitudinal study investigates the association between job displacement and subsequent self-assessed health (SAH). The sample consists of 253 displaced workers and a comparison group of 6,934 continuously-employed workers. Controlling for baseline SAH and standard demographic characteristics, we find no statistical association between job displacement and subsequent SAH. Our findings are consiste...

  14. DISPLACEMENT OF TRIBAL: NATURE, FORMS AND INFORMATIONOF MYSORE DISTRICT

    OpenAIRE

    Mahalinga K.

    2014-01-01

    Over the past couple of year’s issues of displacement or eviction of tribal from their original land due to various reasons has become a major contentious issue. Now displacement has been recognized as a fact. This is now reflected in many of the policy documents. Apart from depriving them of their lands, livelihoods and resource-base, displacement has other traumatic psychological and sociocultural consequences.Such an approach is especially necessary in respect of tribal, small ...

  15. Experimental Validation of Displacement Underestimation in ARFI Ultrasound

    OpenAIRE

    Czernuszewicz, Tomasz J.; Streeter, Jason E.; Paul A. Dayton; GALLIPPI, CATERINA M.

    2013-01-01

    Acoustic radiation force impulse (ARFI) imaging is an elastography technique that uses ultrasonic pulses to both displace and track tissue motion. Previous modeling studies have shown that ARFI displacements are susceptible to underestimation due to lateral and elevational shearing that occurs within the tracking resolution cell. In this study, optical tracking was utilized to experimentally measure the displacement underestimation achieved by acoustic tracking using a clinical ultrasound sys...

  16. PROJECT-INDUCED DISPLACEMENT, SECONDARY STRESSORS, AND HEALTH

    OpenAIRE

    Cao, Yue; Hwang, Sean-Shong; Xi, Juan

    2012-01-01

    It has been estimated that about 15 million people are displaced by development projects around the world each year. Despite the magnitude of people affected, research on the health and other impacts of project-induced displacement is rare. This study extends existing knowledge by exploring the short-term health impact of a large scale population displacement resulting from China’s Three Gorges Dam Project. The study is theoretically guided by the stress process model, but we supplement it wi...

  17. Calculation of Gamma Displacement Cross Sections: Generation of Recoil Spectra from ENDF/B-VII

    International Nuclear Information System (INIS)

    Radiation damage in materials is caused by the transfer of energy from an incident particle to the target atoms, which results in the redistribution of target atoms. During the nuclear reactor operation, various kinds of radiation are produced, including fast neutron, gamma, beta, high-energy ions etc. These radiations may affect the properties of reactor structural materials in a direct and/or indirect way. It is well known that fast neutrons have an effect on the degradation of materials. Whereas the impact of fast neutrons (En > 1 MeV) on material property changes is clearly recognized, the impact of gamma ray damage to materials is usually not significant. However, there has been some interest in gamma ray damage in metals in promoting accelerated embrittlement of reactor pressure vessel steels in the HFIR (High Flux Isotopes Reactor). In situations where there is a large water gap between pressure vessel and fuel assembly, gamma damage can become comparable to that produced by neutrons, on the basis of displacements per atom (dpa) parameter. A recent analysis of gamma ray displacement damage in the RPV of the General Electric Advanced Boiling Water Reactor (ABWR) indicated that the ratio of calculated gamma- to neutron-induced displacement damage rates is over 100% at the RPV inner diameter. Under a high gamma dose environment, embrittlement can be accelerated by radiation-enhanced mass transport mechanism. Because gamma rays are much more efficient than neutrons at producing freely-migrating defects, any radiation enhanced or induced processes that depend on the magnitude of defect fluxes to sinks, can be disproportionately affected by gamma. The direct evaluation of the contribution of gamma ray to damage in materials, quantified as a parameter of dpa, is made possible once the displacement damage cross section due to gamma rays are known. In this work, we present calculations for gamma ray displacement cross sections in various materials in the energy range from 0 to 14 MeV

  18. Tracking log displacement during floods in the Tagliamento River using RFID and GPS tracker devices

    Science.gov (United States)

    Ravazzolo, D.; Mao, L.; Picco, L.; Lenzi, M. A.

    2015-01-01

    Large pieces of in-channel wood can exert an important role on the ecological and morphological properties of gravel-bed rivers. On the other side, when transported during flood events, large wood can become a source of risk for sensitive structures such as bridges. However, wood displacement and velocity in river systems are still poorly understood, especially in large gravel-bed rivers. This study focuses on log transport in a valley reach of Tagliamento River (Italy). Log displacement during flood events of different magnitudes recorded from June 2010 to October 2011 has been analysed thanks to the installation of 113 radio frequency identification (RFID) tags and 42 GPS tracker devices in logs of different dimensions. Recovery rates of logs equipped with RFID and GPS trackers were about 43% and 42%, respectively. The GPS devices allowed us to analyse in details the log displacement and transport overtime, indicating a higher log entrainment during rising limb of hydrographs. The threshold for the entrainment of logs from low bars is around 40% of bankfull water stage. No clear relationship was found between the peak of flood and log displacement length and velocity. However, log displacement length and velocity appear significantly correlated to the ratio between the peak of flow and the water stage exceeding the flow duration curve for 25% of time (i.e. the ratio hmax/h25 ratio). Log deposition was observed to occur at the peak flow, and logs transported during ordinary events are preferably deposited on low bars. This study reveals the potentials of GPS tracker devices to monitor the entrainment and movements of logs in large gravel-bed rivers during floods. These observations could be useful for better planning of river management practices and strategies involving the use of large wood pieces and could help for calibrating wood budgets at the reach scale.

  19. Atypical water lattices and their possible relevance to the amorphous ices: A density functional study

    OpenAIRE

    Anick, David J

    2013-01-01

    Of the fifteen known crystalline forms of ice, eleven consist of a single topologically connected hydrogen bond network with four H-bonds at every O. The other four, Ices VI–VIII and XV, consist of two topologically connected networks, each with four H-bonds at every O. The networks interpenetrate but do not share H-bonds. This article presents two new periodic water lattice families whose topological connectivity is “atypical”: they consist of many two-dimensional layers that share no H-bond...

  20. Hybrid staging of a Lysholm positive displacement engine with two Westinghouse two stage impulse Curtis turbines

    Energy Technology Data Exchange (ETDEWEB)

    Parker, D.A.

    1982-06-01

    The University of California at Berkeley has tested and modeled satisfactorly a hybrid staged Lysholm engine (positive displacement) with a two stage Curtis wheel turbine. The system operates in a stable manner over its operating range (0/1-3/1 water ratio, 120 psia input). Proposals are made for controlling interstage pressure with a partial admission turbine and volume expansion to control mass flow and pressure ratio for the Lysholm engine.