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Sample records for relative permeability relationships

  1. Relative Permeability of Fractured Rock

    Energy Technology Data Exchange (ETDEWEB)

    Mark D. Habana

    2002-06-30

    Contemporary understanding of multiphase flow through fractures is limited. Different studies using synthetic fractures and various fluids have yielded different relative permeability-saturation relations. This study aimed to extend the understanding of multiphase flow by conducting nitrogen-water relative permeability experiments on a naturally-fractured rock from The Geysers geothermal field. The steady-state approach was used. However, steady state was achieved only at the endpoint saturations. Several difficulties were encountered that are attributed to phase interference and changes in fracture aperture and surface roughness, along with fracture propagation/initiation. Absolute permeabilities were determined using nitrogen and water. The permeability values obtained change with the number of load cycles. Determining the absolute permeability of a core is especially important in a fractured rock. The rock may change as asperities are destroyed and fractures propagate or st rain harden as the net stresses vary. Pressure spikes occurred in water a solute permeability experiments. Conceptual models of an elastic fracture network can explain the pressure spike behavior. At the endpoint saturations the water relative permeabilities obtained are much less than the nitrogen gas relative permeabilities. Saturations were determined by weighing and by resistivity calculations. The resistivity-saturation relationship developed for the core gave saturation values that differ by 5% from the value determined by weighing. Further work is required to complete the relative permeability curve. The steady-state experimental approach encountered difficulties due to phase interference and fracture change. Steady state may not be reached until an impractical length of time. Thus, unsteady-state methods should be pursued. In unsteady-state experiments the challenge will be in quantifying rock fracture change in addition to fluid flow changes.

  2. Permeability-Porosity Relationships of Subduction Zone Sediments

    Science.gov (United States)

    Gamage, K.; Screaton, E.; Bekins, B.; Aiello, I.

    2008-12-01

    Permeability-porosity relationships for sediments from Northern Barbados, Costa Rica, Nankai, and Peru subduction zones were examined based on their sediment type and grain size distribution. Greater correlation was observed between permeability and porosity for siliciclastic sediments, diatom oozes, and nannofossil chalk than for nannofossil oozes. For siliciclastic sediments, grouping of sediments by clay content yields relationships that are generally consistent with results from other marine settings and suggest decreasing permeability for a given porosity as clay content increases. Correction of measured porosities for smectite content generally improves the quality of permeability-porosity relationships. The relationship between permeability and porosity for diatom oozes may be controlled by the amount of clay present in the ooze, causing diatom oozes to behave similarly to siliciclastic sediments. For a given porosity the nannofossil oozes have higher permeability values by 1.5 orders of magnitude than the siliciclastic sediments. However, the use of a permeability-porosity relation may not be appropriate for unconsolidated carbonates such as nannofossil oozes. This study provided insight to the effects of porosity correction for smectite, variations in lithology and grain size in permeability-porosity relationships. However, further progress in delineating controls on permeability will require more careful and better documented permeability tests on characterized samples.

  3. Steam-water relative permeability

    Energy Technology Data Exchange (ETDEWEB)

    Ambusso, W.; Satik, C.; Home, R.N. [Stanford Univ., CA (United States)

    1997-12-31

    A set of relative permeability relations for simultaneous flow of steam and water in porous media have been measured in steady state experiments conducted under the conditions that eliminate most errors associated with saturation and pressure measurements. These relations show that the relative permeabilities for steam-water flow in porous media vary approximately linearly with saturation. This departure from the nitrogen/water behavior indicates that there are fundamental differences between steam/water and nitrogen/water flows. The saturations in these experiments were measured by using a high resolution X-ray computer tomography (CT) scanner. In addition the pressure gradients were obtained from the measurements of liquid phase pressure over the portions with flat saturation profiles. These two aspects constitute a major improvement in the experimental method compared to those used in the past. Comparison of the saturation profiles measured by the X-ray CT scanner during the experiments shows a good agreement with those predicted by numerical simulations. To obtain results that are applicable to general flow of steam and water in porous media similar experiments will be conducted at higher temperature and with porous rocks of different wetting characteristics and porosity distribution.

  4. Frictional stability-permeability relationships for fractures in shales

    Science.gov (United States)

    Fang, Yi; Elsworth, Derek; Wang, Chaoyi; Ishibashi, Takuya; Fitts, Jeffrey P.

    2017-03-01

    There is wide concern that fluid injection in the subsurface, such as for the stimulation of shale reservoirs or for geological CO2 sequestration (GCS), has the potential to induce seismicity that may change reservoir permeability due to fault slip. However, the impact of induced seismicity on fracture permeability evolution remains unclear due to the spectrum of modes of fault reactivation (e.g., stable versus unstable). As seismicity is controlled by the frictional response of fractures, we explore friction-stability-permeability relationships through the concurrent measurement of frictional and hydraulic properties of artificial fractures in Green River shale (GRS) and Opalinus shale (OPS). We observe that carbonate-rich GRS shows higher frictional strength but weak neutral frictional stability. The GRS fracture permeability declines during shearing while an increased sliding velocity reduces the rate of permeability decline. By comparison, the phyllosilicate-rich OPS has lower friction and strong stability while the fracture permeability is reduced due to the swelling behavior that dominates over the shearing induced permeability reduction. Hence, we conclude that the friction-stability-permeability relationship of a fracture is largely controlled by mineral composition and that shale mineral compositions with strong frictional stability may be particularly subject to permanent permeability reduction during fluid infiltration.

  5. Porosity, permeability, and their relationship in granite, basalt, and tuff

    International Nuclear Information System (INIS)

    1983-04-01

    This report discusses the porosity, storage, and permeability of fractured (mainly crystalline) rock types proposed as host rock for nuclear waste repositories. The emphasis is on the inter-relationships of these properties, but a number of reported measurements are included as well. The porosity of rock is shown to consist of fracture porosity and matrix porosity; techniques are described for determining the total interconnected porosity through both laboratory and field measurement. Permeability coefficient, as obtained by experiments ranging from laboratory to crustal scale, is discussed. Finally, the problem of determining the relationship between porosity and permeability is discussed. There is no simple, all encompassing relationship that describes the dependence of permeability upon porosity. However, two particular cases have been successfully analyzed: flow through a single rough fracture, and flow through isotropic porous rock. These two cases are discussed in this report

  6. Structure-skin permeability relationship of dendrimers.

    Science.gov (United States)

    Venuganti, Venkata Vamsi; Sahdev, Preety; Hildreth, Michael; Guan, Xiangming; Perumal, Omathanu

    2011-09-01

    To investigate skin penetration of poly (amidoamine) (PAMAM) dendrimers as a function of surface charge and molecular weight in presence and absence of iontophoresis. Dendrimers were labeled with fluoroisothiocynate (FITC); skin penetration of dendrimers was studied using excised porcine skin in-vitro. Skin penetration of FITC-labeled dendrimers was quantified using confocal laser scanning microscope (CLSM). G2-G6 NH(2), G3.5-COOH and G4-OH dendrimers were used. Cationic dendrimers showed higher skin penetration than neutral and anionic dendrimers. Skin penetration of cationic dendrimer increased linearly with increase in treatment time. Iontophoresis enhanced skin penetration of cationic and neutral dendrimers. Increase in current strength and current duration increased skin transport of dendrimers. Passive and iontophoretic skin penetration of cationic dendrimers was inversely related to their molecular weight. Dendrimer penetrated the skin through intercellular lipids and hair follicles. With iontophoresis, dendrimer was also found in localized skin regions. The study demonstrates that the physicochemical properties of dendrimers influence their skin transport. Findings can be used to design dendrimer-based nanocarriers for drug delivery to skin.

  7. Sub-core permeability and relative permeability characterization with Positron Emission Tomography

    Science.gov (United States)

    Zahasky, C.; Benson, S. M.

    2017-12-01

    This study utilizes preclinical micro-Positron Emission Tomography (PET) to image and quantify the transport behavior of pulses of a conservative aqueous radiotracer injected during single and multiphase flow experiments in a Berea sandstone core with axial parallel bedding heterogeneity. The core is discretized into streamtubes, and using the micro-PET data, expressions are derived from spatial moment analysis for calculating sub-core scale tracer flux and pore water velocity. Using the flux and velocity data, it is then possible to calculate porosity and saturation from volumetric flux balance, and calculate permeability and water relative permeability from Darcy's law. Full 3D simulations are then constructed based on this core characterization. Simulation results are compared with experimental results in order to test the assumptions of the simple streamtube model. Errors and limitations of this analysis will be discussed. These new methods of imaging and sub-core permeability and relative permeability measurements enable experimental quantification of transport behavior across scales.

  8. Measurement of relative permeability of fuel cell diffusion media

    KAUST Repository

    Hussaini, I.S.; Wang, C.Y.

    2010-01-01

    Gas diffusion layer (GDL) in PEM fuel cells plays a pivotal role in water management. Modeling of liquid water transport through the GDL relies on knowledge of relative permeability functions in the in-plane and through-plane directions

  9. Measurement of relative permeability of fuel cell diffusion media

    KAUST Repository

    Hussaini, I.S.

    2010-06-01

    Gas diffusion layer (GDL) in PEM fuel cells plays a pivotal role in water management. Modeling of liquid water transport through the GDL relies on knowledge of relative permeability functions in the in-plane and through-plane directions. In the present work, air and water relative permeabilities are experimentally determined as functions of saturation for typical GDL materials such as Toray-060, -090, -120 carbon paper and E-Tek carbon cloth materials in their plain, untreated forms. Saturation is measured using an ex situ gravimetric method. Absolute and relative permeability functions in the two directions of interest are presented and new correlations for in-plane relative permeability of water and air are established. © 2010 Elsevier B.V. All rights reserved.

  10. Permeability - Fluid Pressure - Stress Relationship in Fault Zones in Shales

    Science.gov (United States)

    Henry, P.; Guglielmi, Y.; Morereau, A.; Seguy, S.; Castilla, R.; Nussbaum, C.; Dick, P.; Durand, J.; Jaeggi, D.; Donze, F. V.; Tsopela, A.

    2016-12-01

    Fault permeability is known to depend strongly on stress and fluid pressures. Exponential relationships between permeability and effective pressure have been proposed to approximate fault response to fluid pressure variations. However, the applicability of these largely empirical laws remains questionable, as they do not take into account shear stress and shear strain. A series of experiments using mHPP probes have been performed within fault zones in very low permeability (less than 10-19 m2) Lower Jurassic shale formations at Tournemire (France) and Mont Terri (Switzerland) underground laboratories. These probes allow to monitor 3D displacement between two points anchored to the borehole walls at the same time as fluid pressure and flow rate. In addition, in the Mont-Terri experiment, passive pressure sensors were installed in observation boreholes. Fracture transmissivity was estimated from single borehole pulse test, constant pressure injection tests, and cross-hole tests. It is found that the transmissivity-pressure dependency can be approximated with an exponential law, but only above a pressure threshold that we call the Fracture Opening Threshold (F.O.P). The displacement data show a change of the mechanical response across the F.O.P. The displacement below the F.O.P. is dominated by borehole response, which is mostly elastic. Above F.O.P., the poro-elasto-plastic response of the fractures dominates. Stress determinations based on previous work and on the analysis of slip data from mHPPP probe indicate that the F.O.P. is lower than the least principal stress. Below the F.O.P., uncemented fractures retain some permeability, as pulse tests performed at low pressures yield diffusivities in the range 10-2 to 10-5 m2/s. Overall, this dual behavior appears consistent with the results of CORK experiments performed in accretionary wedge decollements. Results suggest (1) that fault zones become highly permeable when approaching the critical Coulomb threshold (2

  11. Gas-liquid Relative Permeability Estimation in 2D Porous Media by Lattice Boltzmann Method: Low Viscosity Ratio 2D LBM Relative Permeability

    Directory of Open Access Journals (Sweden)

    Sadegh Mahmoudi

    2013-04-01

    Full Text Available This work is a primary achievement in studying the CO2 and N2–oil systems. To predict gas-liquid relative permeability curves, a Shan-Chen type multicomponent multiphase lattice Boltzmann model for two-phase flow through 2D porous media is developed. Periodic and bounce back boundary conditions are applied to the model with the Guo scheme for the external body force (i.e., the pressure gradient. The influence of relationship between cohesion and adsorption parameters and the interfacial tension values in Young's equation, pore structure (micro scan image derived porous media response is compared with corresponding porosity and permeability ideal sphere pack structure, and saturation distribution on relative permeability curves are studied with the aim to achieve the realistic stable condition for the simulation of gas-liquid systems with a low viscosity ratio.

  12. Calculation of large scale relative permeabilities from stochastic properties of the permeability field and fluid properties

    Energy Technology Data Exchange (ETDEWEB)

    Lenormand, R.; Thiele, M.R. [Institut Francais du Petrole, Rueil Malmaison (France)

    1997-08-01

    The paper describes the method and presents preliminary results for the calculation of homogenized relative permeabilities using stochastic properties of the permeability field. In heterogeneous media, the spreading of an injected fluid is mainly sue to the permeability heterogeneity and viscosity fingering. At large scale, when the heterogeneous medium is replaced by a homogeneous one, we need to introduce a homogenized (or pseudo) relative permeability to obtain the same spreading. Generally, is derived by using fine-grid numerical simulations (Kyte and Berry). However, this operation is time consuming and cannot be performed for all the meshes of the reservoir. We propose an alternate method which uses the information given by the stochastic properties of the field without any numerical simulation. The method is based on recent developments on homogenized transport equations (the {open_quotes}MHD{close_quotes} equation, Lenormand SPE 30797). The MHD equation accounts for the three basic mechanisms of spreading of the injected fluid: (1) Dispersive spreading due to small scale randomness, characterized by a macrodispersion coefficient D. (2) Convective spreading due to large scale heterogeneities (layers) characterized by a heterogeneity factor H. (3) Viscous fingering characterized by an apparent viscosity ration M. In the paper, we first derive the parameters D and H as functions of variance and correlation length of the permeability field. The results are shown to be in good agreement with fine-grid simulations. The are then derived a function of D, H and M. The main result is that this approach lead to a time dependent . Finally, the calculated are compared to the values derived by history matching using fine-grid numerical simulations.

  13. Analytical Estimation of Water-Oil Relative Permeabilities through Fractures

    Directory of Open Access Journals (Sweden)

    Saboorian-Jooybari Hadi

    2016-05-01

    Full Text Available Modeling multiphase flow through fractures is a key issue for understanding flow mechanism and performance prediction of fractured petroleum reservoirs, geothermal reservoirs, underground aquifers and carbon-dioxide sequestration. One of the most challenging subjects in modeling of fractured petroleum reservoirs is quantifying fluids competition for flow in fracture network (relative permeability curves. Unfortunately, there is no standard technique for experimental measurement of relative permeabilities through fractures and the existing methods are very expensive, time consuming and erroneous. Although, several formulations were presented to calculate fracture relative permeability curves in the form of linear and power functions of flowing fluids saturation, it is still unclear what form of relative permeability curves must be used for proper modeling of flow through fractures and consequently accurate reservoir simulation. Basically, the classic linear relative permeability (X-type curves are used in almost all of reservoir simulators. In this work, basic fluid flow equations are combined to develop a new simple analytical model for water-oil two phase flow in a single fracture. The model gives rise to simple analytic formulations for fracture relative permeabilities. The model explicitly proves that water-oil relative permeabilities in fracture network are functions of fluids saturation, viscosity ratio, fluids density, inclination of fracture plane from horizon, pressure gradient along fracture and rock matrix wettability, however they were considered to be only functions of saturations in the classic X-type and power (Corey [35] and Honarpour et al. [28, 29] models. Eventually, validity of the proposed formulations is checked against literature experimental data. The proposed fracture relative permeability functions have several advantages over the existing ones. Firstly, they are explicit functions of the parameters which are known for

  14. Evaluation of methods for measuring relative permeability of anhydride from the Salado Formation: Sensitivity analysis and data reduction

    International Nuclear Information System (INIS)

    Christiansen, R.L.; Kalbus, J.S.

    1997-05-01

    This report documents, demonstrates, evaluates, and provides theoretical justification for methods used to convert experimental data into relative permeability relationships. The report facilities accurate determination of relative permeabilities of anhydride rock samples from the Salado Formation at the Waste Isolation Pilot Plant (WIPP). Relative permeability characteristic curves are necessary for WIPP Performance Assessment (PA) predictions of the potential for flow of waste-generated gas from the repository and brine flow into repository. This report follows Christiansen and Howarth (1995), a comprehensive literature review of methods for measuring relative permeability. It focuses on unsteady-state experiments and describes five methods for obtaining relative permeability relationships from unsteady-state experiments. Unsteady-state experimental methods were recommended for relative permeability measurements of low-permeability anhydrite rock samples form the Salado Formation because these tests produce accurate relative permeability information and take significantly less time to complete than steady-state tests. Five methods for obtaining relative permeability relationships from unsteady-state experiments are described: the Welge method, the Johnson-Bossler-Naumann method, the Jones-Roszelle method, the Ramakrishnan-Cappiello method, and the Hagoort method. A summary, an example of the calculations, and a theoretical justification are provided for each of the five methods. Displacements in porous media are numerically simulated for the calculation examples. The simulated product data were processed using the methods, and the relative permeabilities obtained were compared with those input to the numerical model. A variety of operating conditions were simulated to show sensitivity of production behavior to rock-fluid properties

  15. Relative permeability of the endothelium and epithelium of rabbit lungs

    International Nuclear Information System (INIS)

    Effros, R.M.; Mason, G.R.; Silverman, P.; Hukkanen, J.

    1986-01-01

    Electron micrographic studies of lungs suggest that the epithelial cells are more tightly joined than the underlying endothelium, and macromolecules penetrate the endothelium more readily than the epithelium. Comparisons of epithelial and endothelial permeability to small molecules have been based upon the relative rates at which solutes traverse the alveolar-capillary barrier in fluid filled lungs and those at which they equilibrate across the capillaries in air-filled lungs. Because the former process is much slower than the latter, it has been concluded that the epithelium is less permeable to small solutes than the endothelium. However this difference may be related to inadequate access of solutes to airway surfaces. In this study, solute losses from the vascular space were compared to those from the airspace in perfused, fluid-filled rabbit lungs. 36 Cl - and 125 I - were lost from air-spaces almost twice as rapidly as 22 Na + . In contrast, the endothelium is equally permeable to 22 Na + and these anions. Loss of 3 H-mannitol from the perfusate resembled that of 22 Na + for about 30 minutes, after which diffusion of 3 H-mannitol into the tissue nearly ceased. These observations suggest that the epithelium is more permselective than the endothelium. By resisting solute and water transport, the epithelium tends to prevent alveolar flooding and confines edema to the interstitium, where it is less likely to interfere with gas exchange

  16. Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

    International Nuclear Information System (INIS)

    Alves, Vinicius M.; Muratov, Eugene; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

    2015-01-01

    Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R 2 = 0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q 2 ext = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. - Highlights: • It was compiled the largest publicly-available skin permeability dataset. • Predictive QSAR models were developed for skin permeability. • No concordance between skin sensitization and

  17. Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Vinicius M. [Laboratory of Molecular Modeling and Design, Faculty of Pharmacy, Federal University of Goiás, Goiânia, GO 74605-220 (Brazil); Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States); Muratov, Eugene [Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States); Laboratory of Theoretical Chemistry, A.V. Bogatsky Physical–Chemical Institute NAS of Ukraine, Odessa 65080 (Ukraine); Fourches, Denis [Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States); Strickland, Judy; Kleinstreuer, Nicole [ILS/Contractor supporting the NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM), P.O. Box 13501, Research Triangle Park, NC 27709 (United States); Andrade, Carolina H. [Laboratory of Molecular Modeling and Design, Faculty of Pharmacy, Federal University of Goiás, Goiânia, GO 74605-220 (Brazil); Tropsha, Alexander, E-mail: alex_tropsha@unc.edu [Laboratory for Molecular Modeling, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599 (United States)

    2015-04-15

    Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R{sup 2} = 0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q{sup 2}{sub ext} = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. - Highlights: • It was compiled the largest publicly-available skin permeability dataset. • Predictive QSAR models were developed for skin permeability. • No concordance between skin

  18. Relationship between permeability and damage in concretes at high temperature

    International Nuclear Information System (INIS)

    Dal Pont, St.

    2004-09-01

    Due to its technical and economical advantages, concrete is nowadays the most used building material in civil engineering. Even if its use is known since nearly two centuries, its behavior has not been yet completely explained due to the complexity of its porous microstructure. This fact is quite evident under particular conditions such as, by instance, during an elevation of temperature. This condition can mainly occur in two cases: due to a casualty (e.g. a fire) or in normal use conditions (e.g. storage of nuclear rejects). This work aims at contributing to the study of the phenomena that can be observed in concrete exposed to high temperatures and, in particular, focuses on the study of the evolution of intrinsic permeability. The characterisation of permeability (which is hardly measurable in hot conditions) is necessary for describing and modelling transport phenomena which occur in porous media. An experimental study has been made in collaboration with the CEA. A real-scale hollow cylinder has been instrumented with gauges for studying the evolution of temperature and gas pressure fields inside concrete. Later, the cylinder has been then numerically modelled by means of a thermo-hydro-chemical (THC) and a thermo-hydro-chemo-mechanical (THCM) model. The THC model, implemented by means of the finite volume method, has allowed a first, qualitative study of the behaviour of concrete submitted to high temperature. This model, which, for sake of simplicity, has neglected all mechanical effects, has allowed the description of the main phenomena occurring inside concrete: mass transport, phase changes, microstructure evolution. Later, the modelling has been completed by means of the THCM model using the Hitecosp code, implemented by means of the finite element method at the university of Padua. This code allows a very complete description of the phenomena occurring inside concrete and takes into consideration the mechanical behavior of concrete by means of an

  19. The Effect of Wettability Heterogeneity on Relative Permeability of Two-Phase Flow in Porous Media: A Lattice Boltzmann Study

    Science.gov (United States)

    Zhao, Jianlin; Kang, Qinjun; Yao, Jun; Viswanathan, Hari; Pawar, Rajesh; Zhang, Lei; Sun, Hai

    2018-02-01

    Relative permeability is a critical parameter characterizing multiphase flow in porous media and it is strongly dependent on the wettability. In many situations, the porous media are nonuniformly wet. To investigate the effect of wettability heterogeneity on relative permeability of two-phase flow in porous media, a multi-relaxation-time color-gradient lattice Boltzmann model is adopted to simulate oil/water two-phase flow in porous media with different oil-wet solid fractions. For the water phase, when the water saturation is high, the relative permeability of water increases with the increase of oil-wet solid fraction under a constant water saturation. However, as the water saturation decreases to an intermediate value (about 0.4-0.7), the relative permeability of water in fractionally wet porous media could be lower than that in purely water-wet porous media, meaning additional flow resistance exists in the fractionally wet porous media. For the oil phase, similar phenomenon is observed. This phenomenon is mainly caused by the wettability-related microscale fluid distribution. According to both our simulation results and theoretical analysis, it is found that the relative permeability of two-phase flow in porous media is strongly related to three parameters: the fluid saturation, the specific interfacial length of fluid, and the fluid tortuosity in the flow direction. The relationship between the relative permeability and these parameters under different capillary numbers is explored in this paper.

  20. Effects of phase transformation of steam-water relative permeabilities

    Energy Technology Data Exchange (ETDEWEB)

    Verma, A.K.

    1986-03-01

    A combined theoretical and experimental study of steam-water relative permeabilities (RPs) was carried out. First, an experimental study of two-phase concurrent flow of steam and water was conducted and a set of RP curves was obtained. These curves were compared with semi-empirical and experimental results obtained by other investigators for two-phase, two-component flow (oil/gas; gas/water; gas/oil). It was found that while the wetting phase RPs were in good agreement, RPs for the steam phase were considerably higher than the non-wetting phase RPs in two-component systems. This enhancement of steam RP is attributed to phase transformation effects at the pore level in flow channels. The effects of phase transformation were studied theoretically. This study indicates that there are two separate mechanisms by which phase transformation affects RP curves: (1) Phase transformation is converging-diverging flow channels can cause an enhancement of steam phase RP. In a channel dominated by steam a fraction of the flowing steam condenses upstream from the constriction, depositing its latent heat of condensation. This heat is conducted through the solid grains around the pore throat, and evaporation takes place downstream from it. Therefore, for a given bulk flow quality; a smaller fraction of steam actually flows through the throat segments. This pore-level effect manifests itself as relative permeability enhancement on a macroscopic level; and (2) phase transformation along the interface of a stagnant phase and the phase flowing around it controls the irreducible phase saturation. Therefore, the irreducible phase saturation in steam-water flow will depend, among other factors, on the boundary conditions of the flow.

  1. A fractal model for predicting permeability and liquid water relative permeability in the gas diffusion layer (GDL) of PEMFCs

    Science.gov (United States)

    He, Guangli; Zhao, Zongchang; Ming, Pingwen; Abuliti, Abudula; Yin, Caoyong

    In this study, a fractal model is developed to predict the permeability and liquid water relative permeability of the GDL (TGP-H-120 carbon paper) in proton exchange membrane fuel cells (PEMFCs), based on the micrographs (by SEM, i.e. scanning electron microscope) of the TGP-H-120. Pore size distribution (PSD), maximum pore size, porosity, diameter of the carbon fiber, pore tortuosity, area dimension, hydrophilicity or hydrophobicity, the thickness of GDL and saturation are involved in this model. The model was validated by comparison between the predicted results and experimental data. The results indicate that the water relative permeability in the hydrophobicity case is much higher than in the hydrophilicity case. So, a hydrophobic carbon paper is preferred for efficient removal of liquid water from the cathode of PEMFCs.

  2. Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

    Science.gov (United States)

    Alves, Vinicius M.; Muratov, Eugene; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

    2015-01-01

    Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R2=0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q2ext = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential. PMID:25560673

  3. Cross-property relations and permeability estimation in model porous media

    International Nuclear Information System (INIS)

    Schwartz, L.M.; Martys, N.; Bentz, D.P.; Garboczi, E.J.; Torquato, S.

    1993-01-01

    Results from a numerical study examining cross-property relations linking fluid permeability to diffusive and electrical properties are presented. Numerical solutions of the Stokes equations in three-dimensional consolidated granular packings are employed to provide a basis of comparison between different permeability estimates. Estimates based on the Λ parameter (a length derived from electrical conduction) and on d c (a length derived from immiscible displacement) are found to be considerably more reliable than estimates based on rigorous permeability bounds related to pore space diffusion. We propose two hybrid relations based on diffusion which provide more accurate estimates than either of the rigorous permeability bounds

  4. Sensitivity Analysis of Interfacial Tension on Saturation and Relative Permeability Model Predictions

    KAUST Repository

    Abdallah, Wael; Zhao, Weishu; Gmira, Ahmed; Negara, Ardiansyah; Buiting, Jan

    2011-01-01

    Interfacial tension (IFT) measurements of Dodecane/brine systems at different concentrations and Dodecane/deionized water subject to different Dodecane purification cycles were taken over extended durations at room temperature and pressure to investigate the impact of aging. When a fresh droplet was formed, a sharp drop in IFT was observed assumed to be a result of intrinsic impurity adsorption at the interface. The subsequent measurements exhibited a prolonged equilibration period consistent with diffusion from the bulk phase to the interface. Our results indicate that minute amounts of impurities present in experimental chemical fluids "used as received" have a drastic impact on the properties of the interface. Initial and equilibrium IFT are shown to be dramatically different, therefore it is important to be cautious of utilizing IFT values in numerical models. The study demonstrates the impact these variations in IFT have on relative permeability relationships by adopting a simple pore network model simulation.

  5. Sensitivity Analysis of Interfacial Tension on Saturation and Relative Permeability Model Predictions

    KAUST Repository

    Abdallah, Wael

    2011-05-18

    Interfacial tension (IFT) measurements of Dodecane/brine systems at different concentrations and Dodecane/deionized water subject to different Dodecane purification cycles were taken over extended durations at room temperature and pressure to investigate the impact of aging. When a fresh droplet was formed, a sharp drop in IFT was observed assumed to be a result of intrinsic impurity adsorption at the interface. The subsequent measurements exhibited a prolonged equilibration period consistent with diffusion from the bulk phase to the interface. Our results indicate that minute amounts of impurities present in experimental chemical fluids "used as received" have a drastic impact on the properties of the interface. Initial and equilibrium IFT are shown to be dramatically different, therefore it is important to be cautious of utilizing IFT values in numerical models. The study demonstrates the impact these variations in IFT have on relative permeability relationships by adopting a simple pore network model simulation.

  6. Relationship of pleural effusions to increased permeability pulmonary edema in anesthetized sheep.

    OpenAIRE

    Wiener-Kronish, J P; Broaddus, V C; Albertine, K H; Gropper, M A; Matthay, M A; Staub, N C

    1988-01-01

    We studied anesthetized sheep to determine the relationship between increased permeability pulmonary edema and the development and mechanism of pleural effusion formation. In 12 sheep with intact, closed thoraces, we studied the time course of pleural liquid formation after 0.12 ml/kg i.v. oleic acid. After 1 h, there were no pleural effusions, even though extravascular lung water increased 50% to 6.0 +/- 0.7 g/g dry lung. By 3 h pleural effusions had formed, they reached a maximum at 5 h (48...

  7. Studies on the relationship between epidermal cell turnover kinetics and permeability of hairless mouse skin

    International Nuclear Information System (INIS)

    Han, S.R.

    1988-01-01

    The primary aim of this study was to develop non-invasive, physical means to quantitatively assess the epidermal turnover kinetics and barrier properties of the skin and relate these to the cutaneous irritation which results from ultraviolet light irradiation and mold thermal burns. After systematically injecting radiolabeled glycine, the appearance of radioactivity at the skin's surface indicated the transit time of radiolabeled cells through the skin. By plotting the data as the cumulative specific activity against time and then fitting them with a third order polynomial equation, it is possible to estimate the turnover time of the stratum corneum. The skin turnover was coordinated with non-invasive transepidermal water loss (TEWL) studies determined with an evaporimeter. In vitro diffusion studies of the permeability of hydrocortisone through UVB irradiated and thermally burned skin were also performed. The studies indicated that irritated skin offers a relatively low diffusional resistance to hydrocortisone. Depending on the severity of the trauma, the increases in hydrocortisone's permeability coefficient through irritated skin ranged from a low of about 2 times normal to a high of about 210 times normal. Trauma-induced changes in hydrocortisone permeability parallel changes in TEWL, proving that the barrier deficient state resulting from rapid epidermal turnover is a general phenomenon

  8. Passive advection-dispersion in networks of pipes: Effect of connectivity and relationship to permeability

    Science.gov (United States)

    Bernabé, Y.; Wang, Y.; Qi, T.; Li, M.

    2016-02-01

    The main purpose of this work is to investigate the relationship between passive advection-dispersion and permeability in porous materials presumed to be statistically homogeneous at scales larger than the pore scale but smaller than the reservoir scale. We simulated fluid flow through pipe network realizations with different pipe radius distributions and different levels of connectivity. The flow simulations used periodic boundary conditions, allowing monitoring of the advective motion of solute particles in a large periodic array of identical network realizations. In order to simulate dispersion, we assumed that the solute particles obeyed Taylor dispersion in individual pipes. When a particle entered a pipe, a residence time consistent with local Taylor dispersion was randomly assigned to it. When exiting the pipe, the particle randomly proceeded into one of the pipes connected to the original one according to probabilities proportional to the outgoing volumetric flow in each pipe. For each simulation we tracked the motion of at least 6000 solute particles. The mean fluid velocity was 10-3 ms-1, and the distance traveled was on the order of 10 m. Macroscopic dispersion was quantified using the method of moments. Despite differences arising from using different types of lattices (simple cubic, body-centered cubic, and face-centered cubic), a number of general observations were made. Longitudinal dispersion was at least 1 order of magnitude greater than transverse dispersion, and both strongly increased with decreasing pore connectivity and/or pore size variability. In conditions of variable hydraulic radius and fixed pore connectivity and pore size variability, the simulated dispersivities increased as power laws of the hydraulic radius and, consequently, of permeability, in agreement with previously published experimental results. Based on these observations, we were able to resolve some of the complexity of the relationship between dispersivity and permeability.

  9. A new method for the experimental determination of three-phase relative permeabilities

    International Nuclear Information System (INIS)

    Perez Carrillo, Edgar Ricardo; Jose Francisco Zapata Arango; Santos Santos, Nicolas

    2008-01-01

    Petroleum reservoirs under primary, secondary or tertiary recovery processes usually experience simultaneous flow of three fluids phases (oil, water and gas). Reports on some mathematical models for calculating three-phase relative permeability are available in the Literature. Nevertheless, many of these models were designed based on certain experimental conditions and reservoir rocks and fluids. Therefore, special care has to be taken when applying them to specific reservoirs. At the laboratory level, three-phase relative permeability can be calculated using experimental unsteady-state or steady state methodologies. This paper proposes an unsteady-state methodology to evaluate three-phase relative permeability using the equipment available at the petrophysical analysis Laboratory of the Instituto Colombiano del Petroleo (ICP) of Ecopetrol S.A. Improvements to the equipment were effected in order to achieve accuracy in the unsteady-state measurement of three-phase relative permeability. The target of improvements was directed toward to the attainment of two objectives:1) the modification of the equipment to obtain more reliable experimental data and 2) the appropriate interpretation of the data obtained. Special attention was given to the differential pressure and uncertainty measurement in the determination of fluid saturation in the rock samples. Three experiments for three-phase relative permeability were conducted using a sample A and reservoir rock from the Colombian Foothills. Fluid tests included the utilization of synthetic brine, mineral oil, reservoir crude oil and nitrogen. Two runs were conducted at the laboratory conditions while one run was conducted at reservoir conditions. Experimental results of these tests were compared using 16 mathematical models of three-phase relative permeability. For the three-phase relative permeability to oil, the best correlations between experimental data and tests using Blunt, Hustad Hasen, and Baker's models were

  10. Laboratory-scale measurements of effective relative permeability for layered sands

    Energy Technology Data Exchange (ETDEWEB)

    Butts, M.G.; Korsgaard, S.

    1996-12-31

    Predictions of the impact of remediation or the extent of contamination resulting from spills of gasoline, solvents and other petroleum products, must often be made in complex geological environments. Such problems can be treated by introducing the concept of effective parameters that incorporate the effects of soil layering or other heterogeneities into a large-scale flow description. Studies that derive effective multiphase parameters are few, and approximations are required to treat the non-linear multiphase flow equations. The purpose of this study is to measure effective relative permeabilities for well-defined multi-layered soils at the laboratory scale. Relative permeabilities were determined for homogeneous and layered, unconsolidated sands using the method of Jones and Roszelle (1978). The experimental data show that endpoint relative permeabilities are important in defining the shape of the relative permeability curves, but these cannot be predicted by estimation methods base on capillary pressure data. The most significant feature of the measured effective relative permeability curves is that the entrapped (residual) oil saturation is significantly larger than the residual saturation of the individual layers. This observation agrees with previous theoretical predictions of large-scale entrapment Butts, 1993 and (1995). Enhanced entrapment in heterogeneous soils has several important implications for spill remediation, for example, the reduced efficiency of direct recovery. (au) 17 refs.

  11. Laboratory-scale measurements of effective relative permeability for layered sands

    International Nuclear Information System (INIS)

    Butts, M.G.; Korsgaard, S.

    1996-01-01

    Predictions of the impact of remediation or the extent of contamination resulting from spills of gasoline, solvents and other petroleum products, must often be made in complex geological environments. Such problems can be treated by introducing the concept of effective parameters that incorporate the effects of soil layering or other heterogeneities into a large-scale flow description. Studies that derive effective multiphase parameters are few, and approximations are required to treat the non-linear multiphase flow equations. The purpose of this study is to measure effective relative permeabilities for well-defined multi-layered soils at the laboratory scale. Relative permeabilities were determined for homogeneous and layered, unconsolidated sands using the method of Jones and Roszelle (1978). The experimental data show that endpoint relative permeabilities are important in defining the shape of the relative permeability curves, but these cannot be predicted by estimation methods base on capillary pressure data. The most significant feature of the measured effective relative permeability curves is that the entrapped (residual) oil saturation is significantly larger than the residual saturation of the individual layers. This observation agrees with previous theoretical predictions of large-scale entrapment Butts, 1993 and (1995). Enhanced entrapment in heterogeneous soils has several important implications for spill remediation, for example, the reduced efficiency of direct recovery. (au) 17 refs

  12. Permeability of skin and oral mucosa to water and horseradish peroxidase as related to the thickness of the permeability barrier

    International Nuclear Information System (INIS)

    Squier, C.A.; Hall, B.K.

    1985-01-01

    The permeability of porcine skin and keratinized and nonkeratinized oral mucosa to tritium-labeled water and horseradish peroxidase (HRPO) was determined using perfusion chambers. Small blocks from each tissue were also incubated with HRPO and the extent of penetration visualized microscopically; this enabled measurements to be made of the thickness of the permeability barrier to this water-soluble tracer. Results obtained after inverting the oral mucosa in the chambers or adding metabolic inhibitors indicated that both compounds diffuse across the tissue. The permeability constants derived directly in the study showed that skin was less permeable than oral mucosa and that the floor of the mouth was significantly more permeable than all other regions. When these constants were normalized in terms of a standard permeability barrier thickness and the different tissues compared, the values obtained for skin were again less than those of the oral regions but, of these, the buccal mucosa was significantly higher. The difference in permeability between epidermis and keratinized oral epithelium may be due to differences in the volume density of membrane-coating granules known to exist between the tissues; differences between the oral mucosal regions may reflect differences in the nature of the intercellular barrier material

  13. Experimental Measurement of Relative Permeability Functions for Fuel Cell GDL Materials

    KAUST Repository

    Hussaini, Irfan; Wang, Chao-Yang

    2009-01-01

    Gas diffusion layer in PEM fuel cells plays a pivotal role in water management. Modeling of liquid water transport through the GDL relies on knowledge of relative permeability functions in the in-plane and through-plane directions. In the present work, air and water relative permeabilities are experimentally determined as functions of saturation for typical GDL materials such as Toray-060, -090, -120 carbon paper and E-Tek carbon cloth materials in their plain, untreated forms. Saturation is measured using an ex-situ gravimetric method. Absolute and relative permeability functions in the two directions of interest are presented. Significant departure from the generally assumed cubic function of saturation is observed. ©The Electrochemical Society.

  14. Flow visualization and relative permeability measurements in rough-walled fractures

    International Nuclear Information System (INIS)

    Persoff, P.; Pruess, K.

    1993-01-01

    Two-phase (gas-liquid) flow experiments were done in a natural rock fracture and transparent replicas of natural fractures. Liquid was injected at constant volume flow rate, and gas was injected at either constant mass flow rate or constant pressure. When gas was injected at constant mass flow rate, the gas inlet pressure, and inlet and outlet capillary pressures, generally did not reach steady state but cycled irregularly. Flow visualization showed that this cycling was due to repeated blocking and unblocking of gas flow paths by liquid. Relative permeabilities calculated from flow rate and pressure data show that the sum of the relative permeabilities of the two phases is much less than 1, indicating that each phase interferes strongly with the flow of the other. Comparison of the relative permeability curves with typical curves for porous media (Corey curves) show that the phase interference is stronger in fractures than in typical porous media

  15. Mathematic modeling of the method of measurement relative dielectric permeability

    Science.gov (United States)

    Plotnikova, I. V.; Chicherina, N. V.; Stepanov, A. B.

    2018-05-01

    The method of measuring relative permittivity’s and the position of the interface between layers of a liquid medium is considered in the article. An electric capacitor is a system consisting of two conductors that are separated by a dielectric layer. It is mathematically proven that at any given time it is possible to obtain the values of the relative permittivity in the layers of the liquid medium and to determine the level of the interface between the layers of the two-layer liquid. The estimation of measurement errors is made.

  16. Relative permeability of fractured wellbore cement: an experimental investigation using electrical resistivity monitoring for moisture content

    Science.gov (United States)

    Um, W.; Rod, K. A.; Strickland, C. E.

    2016-12-01

    Permeability is a critical parameter needed to understand flow in subsurface environments; it is particularly important in deep subsurface reservoirs where multiphase fluid flow is common, such as carbon sequestration and geothermal reservoirs. Cement is used in the annulus of wellbores due to its low permeable properties to seal aquifers, reducing leaks to adjacent strata. Extreme subsurface environments of CO2 storage and geothermal production conditions will eventually reduce the cement integrity, propagating fracture networks and increasing the permeability for air and/or water. To date, there have been no reproducible experimental investigations of relative permeability in fractured wellbore cement published. To address this gap, we conducted a series of experiments using fractured Portland cement monoliths with increasing fracture networks. The monolith cylinder sides were jacketed with heavy-duty moisture-seal heat-shrink tubing, then fractured using shear force applied via a hydraulic press. Fractures were generated with different severity for each of three monoliths. Stainless steel endcaps were fixed to the monoliths using the same shrink-wrapped jacket. Fracture characteristics were determined using X-ray microtomography and image analysis. Flow controllers were used to control flow of water and air to supply continuous water or water plus air, both of which were delivered through the influent end cap. Effluent air flow was monitored using a flow meter, and water flow was measured gravimetrically. To monitor the effective saturation of the fractures, a RCON2 concrete bulk electrical resistivity test device was attached across both endcaps and a 0.1M NaNO3 brine was used as the transport fluid to improve resistivity measurements. Water content correlated to resistivity measurements with a r2 > 0.96. Data from the experiments was evaluated using two relative permeability models, the Corey-curve, often used for modeling relative permeability in porous media

  17. 3D numerical surface charge model including relative permeability : the general theory

    NARCIS (Netherlands)

    Casteren, van D.T.E.H.; Paulides, J.J.H.; Lomonova, E.A.

    2014-01-01

    One of the still "open" issues within low-frequency magnetics is the inclusion of µr in the calculations using the magnetic charge method. In this paper a new iterative method to take the relative permeability into account is investigated. Results show that the model accurately accounts for the

  18. Kozeny-Carman permeability relationship with disintegration process predicted from early dissolution profiles of immediate release tablets.

    Science.gov (United States)

    Kumari, Parveen; Rathi, Pooja; Kumar, Virender; Lal, Jatin; Kaur, Harmeet; Singh, Jasbir

    2017-07-01

    This study was oriented toward the disintegration profiling of the diclofenac sodium (DS) immediate-release (IR) tablets and development of its relationship with medium permeability k perm based on Kozeny-Carman equation. Batches (L1-L9) of DS IR tablets with different porosities and specific surface area were prepared at different compression forces and evaluated for porosity, in vitro dissolution and particle-size analysis of the disintegrated mass. The k perm was calculated from porosities and specific surface area, and disintegration profiles were predicted from the dissolution profiles of IR tablets by stripping/residual method. The disintegration profiles were subjected to exponential regression to find out the respective disintegration equations and rate constants k d . Batches L1 and L2 showed the fastest disintegration rates as evident from their bi-exponential equations while the rest of the batches L3-L9 exhibited the first order or mono-exponential disintegration kinetics. The 95% confidence interval (CI 95% ) revealed significant differences between k d values of different batches except L4 and L6. Similar results were also spotted for dissolution profiles of IR tablets by similarity (f 2 ) test. The final relationship between k d and k perm was found to be hyperbolic, signifying the initial effect of k perm on the disintegration rate. The results showed that disintegration profiling is possible because a relationship exists between k d and k perm . The later being relatable with porosity and specific surface area can be determined by nondestructive tests.

  19. Estimation of relative permeability and capillary pressure from mass imbibition experiments

    Science.gov (United States)

    Alyafei, Nayef; Blunt, Martin J.

    2018-05-01

    We perform spontaneous imbibition experiments on three carbonates - Estaillades, Ketton, and Portland - which are three quarry limestones that have very different pore structures and span wide range of permeability. We measure the mass of water imbibed in air saturated cores as a function of time under strongly water-wet conditions. Specifically, we perform co-current spontaneous experiments using a highly sensitive balance to measure the mass imbibed as a function of time for the three rocks. We use cores measuring 37 mm in diameter and three lengths of approximately 76 mm, 204 mm, and 290 mm. We show that the amount imbibed scales as the square root of time and find the parameter C, where the volume imbibed per unit cross-sectional area at time t is Ct1/2. We find higher C values for higher permeability rocks. Employing semi-analytical solutions for one-dimensional flow and using reasonable estimates of relative permeability and capillary pressure, we can match the experimental data. We finally discuss how, in combination with conventional measurements, we can use theoretical solutions and imbibition measurements to find or constrain relative permeability and capillary pressure.

  20. Electromagnetic Monitoring of Hydraulic Fracturing: Relationship to Permeability, Seismicity, and Stress

    Science.gov (United States)

    Thiel, Stephan

    2017-09-01

    Hydraulic fracking is a geoengineering application designed to enhance subsurface permeability to maximize fluid and gas flow. Fracking is commonly used in enhanced geothermal systems (EGS), tight shale gas, and coal seam gas (CSG) plays and in CO_2 storage scenarios. Common monitoring methods include microseismics and mapping small earthquakes with great resolution associated with fracture opening at reservoir depth. Recently, electromagnetic (EM) methods have been employed in the field to provide an alternative way of direct detection of fluids as they are pumped in the ground. Surface magnetotelluric (MT) measurements across EGS show subtle yet detectable changes during fracking derived from time-lapse MT deployments. Changes are directional and are predominantly aligned with current stress field, dictating preferential fracture orientation, supported by microseismic monitoring of frack-related earthquakes. Modeling studies prior to the injection are crucial for survey design and feasibility of monitoring fracks. In particular, knowledge of sediment thickness plays a fundamental role in resolving subtle changes. Numerical forward modeling studies clearly favor some form of downhole measurement to enhance sensitivity; however, these have yet to be conclusively demonstrated in the field. Nevertheless, real surface-based monitoring examples do not necessarily replicate the expected magnitude of change derived from forward modeling and are larger than expected in some cases from EGS and CSG systems. It appears the injected fluid volume alone cannot account for the surface change in resistivity, but connectedness of pore space is also significantly enhanced and nonlinear. Recent numerical studies emphasize the importance of percolation threshold of the fracture network on both electrical resistivity and permeability, which may play an important role in accounting for temporal changes in surface EM measurements during hydraulic fracking.

  1. The fraction dose absorbed, in humans, and high jejunal human permeability relationship.

    Science.gov (United States)

    Dahan, Arik; Lennernäs, Hans; Amidon, Gordon L

    2012-06-04

    The drug intestinal permeability (P(eff)) measure has been widely used as one of the main factors governing both the rate and/or extent of drug absorption (F(abs)) in humans following oral administration. In this communication we emphasize the complexity behind and the care that must be taken with this in vivo P(eff) measurement. Intestinal permeability, considering the whole of the human intestine, is more complex than generally recognized, and this can lead to misjudgment regarding F(abs) and P(eff) in various settings, e.g. drug discovery, formulation design, drug development and regulation. Setting the adequate standard for the low/high permeability class boundary, the different experimental methods for the permeability measurement, and segmental-dependent permeability throughout the human intestine due to different mechanisms are some of the main points that are discussed. Overall, the use of jejunal P(eff) as a surrogate for extent of absorption is sound and scientifically justified; a compound with high jejunal P(eff) will have high F(abs), eliminating the risk for misclassification as a BCS class I drug. Much more care should be taken, however, when jejunal P(eff) does not support a high-permeability classification; a thorough examination may reveal high-permeability after all, attributable to e.g. segmental-dependent permeability due to degree of ionization or transporter expression. In this situation, the use of multiple permeability experimental methods, including the use of metabolism, which except for luminal degradation requires absorption, is prudent and encouraged.

  2. Relationship between changed alveolar-capillary permeability and angiotensin converting enzyme activity in serum in sarcoidosis.

    OpenAIRE

    Eklund, A; Blaschke, E

    1986-01-01

    The effect of altered alveolar-capillary permeability on angiotensin converting enzyme (ACE) activity in serum (SACE) was studied in 45 patients with sarcoidosis and 21 healthy controls. In sarcoidosis increased albumin concentrations in the bronchoalveolar lavage fluid (L albumin) and increased ratios of L albumin to albumin in serum (S albumin) indicated an increased permeability of the alveolar-capillary membrane. ACE activity in the lavage fluid (LACE) was correlated with the number of al...

  3. Stem sapwood permeability in relation to crown dominance and site quality in self-thinning fire-origin lodgepole pine stands.

    Science.gov (United States)

    Reid, Douglas E B; Silins, Uldis; Lieffers, Victor J

    2003-08-01

    Stem sapwood hydraulic permeability, tree leaf area, sapwood basal area, earlywood to latewood ratio of annual rings, radial variation in hydraulic permeability and stem hydraulic capacity were examined in dominant (D), codominant (CD) and suppressed (SP) lodgepole pine (Pinus contorta Dougl. ex Loud.) trees growing on medium and poor sites. Hydraulic permeability on a sapwood area basis (ks) was lower in suppressed trees (0.71 x 10(-12) m2) compared to dominants (1.97 x 10(-12) m2) and codominants (1.79 x 10(-12) m2), and higher on medium than on poor sites. The leaf/sapwood area ratio (S) varied with crown dominance position (D > CD > SP) but not by site type. Leaf specific conductivity (kL) did not vary between crown classes or site types. The relationship between leaf area and stem hydraulic supply capacity (Q*) was strong, but differed among crown classes. Dominant trees and trees from the medium sites had a greater proportion of earlywood in outer rings of sapwood than suppressed trees. Sapwood permeability declined from the cambium to the sapwood-heartwood boundary in all samples, but the decline was more gradual in dominant trees compared to codominant and suppressed trees; differences in the radial variation in sapwood permeability may be related to differences in S. Sapwood permeability is positively related to crown dominance, whereas subdominant (CD and SP) trees have greater Q* in relation to leaf area, leading us to propose that this may give subdominant trees a survival advantage, slowing self-thinning.

  4. Impact of Three-Phase Relative Permeability and Hysteresis Models on Forecasts of Storage Associated With CO2-EOR

    Science.gov (United States)

    Jia, Wei; McPherson, Brian; Pan, Feng; Dai, Zhenxue; Moodie, Nathan; Xiao, Ting

    2018-02-01

    Geological CO2 sequestration in conjunction with enhanced oil recovery (CO2-EOR) includes complex multiphase flow processes compared to CO2 storage in deep saline aquifers. Two of the most important factors affecting multiphase flow in CO2-EOR are three-phase relative permeability and associated hysteresis, both of which are difficult to measure and are usually represented by numerical interpolation models. The purpose of this study is to improve understanding of (1) the relative impacts of different three-phase relative permeability models and hysteresis models on CO2 trapping mechanisms, and (2) uncertainty associated with these two factors. Four different three-phase relative permeability models and three hysteresis models were applied to simulations of an active CO2-EOR site, the SACROC unit located in western Texas. To eliminate possible bias of deterministic parameters, we utilized a sequential Gaussian simulation technique to generate 50 realizations to describe heterogeneity of porosity and permeability, based on data obtained from well logs and seismic survey. Simulation results of forecasted CO2 storage suggested that (1) the choice of three-phase relative permeability model and hysteresis model led to noticeable impacts on forecasted CO2 sequestration capacity; (2) impacts of three-phase relative permeability models and hysteresis models on CO2 trapping are small during the CO2-EOR injection period, and increase during the post-EOR CO2 injection period; (3) the specific choice of hysteresis model is more important relative to the choice of three-phase relative permeability model; and (4) using the recommended three-phase WAG (Water-Alternating-Gas) hysteresis model may increase the impact of three-phase relative permeability models and uncertainty due to heterogeneity.

  5. Verification of capillary pressure functions and relative permeability equations for gas production

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jaewon [Arizona State Univ., Tempe, AZ (United States)

    2016-10-25

    The understanding of multiphase fluid flow in porous media is of great importance in many fields such as enhanced oil recovery, hydrology, CO2 sequestration, contaminants cleanup and natural gas production from hydrate bearing sediments. However, there are many unanswered questions about the key parameters that characterize gas and water flows in porous media. The characteristics of multiphase fluid flow in porous media such as water retention curve, relative permeability, preferential fluid flow patterns and fluid-particle interaction should be taken into consideration for a fundamental understanding of the behavior of pore scale systems.

  6. Plasma endocannabinoid levels in lean, overweight and obese humans: relationships with intestinal permeability markers, inflammation and incretin secretion.

    Science.gov (United States)

    Little, Tanya J; Cvijanovic, Nada; DiPatrizio, Nicholas V; Argueta, Donovan A; Rayner, Christopher K; Feinle-Bisset, Christine; Young, Richard L

    2018-02-13

    Intestinal production of endocannabinoid and oleoylethanolamide (OEA) is impaired in high-fat diet/obese rodents, leading to reduced satiety. Such diets also alter the intestinal microbiome in association with enhanced intestinal permeability and inflammation, however little is known of these effects in humans. This study aimed to: (i) evaluate effects of lipid on plasma anandamide (AEA), 2-arachidonyl-sn-glycerol (2-AG) and OEA in humans, and (ii) examine relationships with intestinal permeability, inflammation markers and incretin hormone secretion. 20 lean, 18 overweight and 19 obese participants underwent intraduodenal Intralipid® infusion (2 kcal/min) with collection of endoscopic duodenal biopsies and blood. Plasma AEA, 2-AG, and OEA (HPLC/tandem mass spectrometry), tumour necrosis factor-α (TNF-α), glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) (multiplex), and duodenal expression of occludin, zona-occludin-1 (ZO-1), intestinal-alkaline-phosphatase (IAP), and toll-like receptor-4 (TLR4) (RT-PCR), were assessed. Fasting plasma AEA was increased in obese, compared with lean and overweight (Plean (Plean and overweight. The relationships between plasma AEA with duodenal ZO-1 and IAP, and GIP, suggest that altered endocannabinoid signalling may contribute to changes in intestinal permeability, inflammation and incretin release in human obesity.

  7. Air-Filled porosity and permeability relationships during solid-waste fermentation

    NARCIS (Netherlands)

    Richard, T.L.; Veeken, A.H.M.; Wilde, de V.; Hamelers, H.V.M.

    2004-01-01

    An experimental apparatus was constructed to measure the structural parameters of organic porous media, i.,e. mechanical strength, air-filled porosity, air permeability, and the Ergun particle size. These parameters are critical to the engineering of aerobic bioconversion systems and were measured

  8. Three-dimensional quantitative structure-permeability relationship analysis for a series of inhibitors of rhinovirus replication.

    Science.gov (United States)

    Ekins, S; Durst, G L; Stratford, R E; Thorner, D A; Lewis, R; Loncharich, R J; Wikel, J H

    2001-01-01

    Multiple three-dimensional quantitative structure-activity relationship (3D-QSAR) approaches were applied to predicting passive Caco-2 permeability for a series of 28 inhibitors of rhinovirus replication. Catalyst, genetic function approximation (GFA) with MS-WHIM descriptors, CoMFA, and VolSurf were all used for generating 3D-quantitative structure permeability relationships utilizing a training set of 19 molecules. Each of these approaches was then compared using a test set of nine molecules not present in the training set. Statistical parameters for the test set predictions (r(2) and leave-one-out q(2)) were used to compare the models. It was found that the Catalyst pharmacophore model was the most predictive (test set of predicted versus observed permeability, r(2) = 0.94). This model consisted of a hydrogen bond acceptor, hydrogen bond donor, and ring aromatic feature with a training set correlation of r(2) = 0.83. The CoMFA model consisted of three components with an r(2) value of 0.96 and produced good predictions for the test set (r(2) = 0.84). VolSurf resulted in an r(2) value of 0.76 and good predictions for the test set (r(2) = 0.83). Test set predictions with GFA/WHIM descriptors (r(2) = 0.46) were inferior when compared with the Catalyst, CoMFA, and VolSurf model predictions in this evaluation. In summary it would appear that the 3D techniques have considerable value in predicting passive permeability for a congeneric series of molecules, representing a valuable asset for drug discovery.

  9. Evaluation of the membrane permeability (PAMPA and skin) of benzimidazoles with potential cannabinoid activity and their relation with the Biopharmaceutics Classification System (BCS).

    Science.gov (United States)

    Alvarez-Figueroa, M Javiera; Pessoa-Mahana, C David; Palavecino-González, M Elisa; Mella-Raipán, Jaime; Espinosa-Bustos, Cristián; Lagos-Muñoz, Manuel E

    2011-06-01

    The permeability of five benzimidazole derivates with potential cannabinoid activity was determined in two models of membranes, parallel artificial membrane permeability assay (PAMPA) and skin, in order to study the relationship of the physicochemical properties of the molecules and characteristics of the membranes with the permeability defined by the Biopharmaceutics Classification System. It was established that the PAMPA intestinal absorption method is a good predictor for classifying these molecules as very permeable, independent of their thermodynamic solubility, if and only if these have a Log P(oct) value permeability is conditioned on the solubility of the molecule so that it can only serve as a model for classifying the permeability of molecules that possess high solubility (class I: high solubility, high permeability; class III: high solubility, low permeability).

  10. Regional-Dependent Intestinal Permeability and BCS Classification: Elucidation of pH-Related Complexity in Rats Using Pseudoephedrine

    OpenAIRE

    Fairstein, Moran; Swissa, Rotem; Dahan, Arik

    2013-01-01

    Based on its lower Log P value relative to metoprolol, a marker for the low/high-permeability (Peff) class boundary, pseudoephedrine was provisionally classified as BCS low-permeability compound. On the other hand, following oral administration, pseudoephedrine fraction dose absorbed (Fabs) and systemic bioavailability approaches 100%. This represents a challenge to the generally recognized Peff–Fabs correlation. The purpose of this study was to elucidate the underlying mechanisms behind the ...

  11. Breaking down the barriers: the gut microbiome, intestinal permeability and stress-related psychiatric disorders

    Science.gov (United States)

    Kelly, John R.; Kennedy, Paul J.; Cryan, John F.; Dinan, Timothy G.; Clarke, Gerard; Hyland, Niall P.

    2015-01-01

    The emerging links between our gut microbiome and the central nervous system (CNS) are regarded as a paradigm shift in neuroscience with possible implications for not only understanding the pathophysiology of stress-related psychiatric disorders, but also their treatment. Thus the gut microbiome and its influence on host barrier function is positioned to be a critical node within the brain-gut axis. Mounting preclinical evidence broadly suggests that the gut microbiota can modulate brain development, function and behavior by immune, endocrine and neural pathways of the brain-gut-microbiota axis. Detailed mechanistic insights explaining these specific interactions are currently underdeveloped. However, the concept that a “leaky gut” may facilitate communication between the microbiota and these key signaling pathways has gained traction. Deficits in intestinal permeability may underpin the chronic low-grade inflammation observed in disorders such as depression and the gut microbiome plays a critical role in regulating intestinal permeability. In this review we will discuss the possible role played by the gut microbiota in maintaining intestinal barrier function and the CNS consequences when it becomes disrupted. We will draw on both clinical and preclinical evidence to support this concept as well as the key features of the gut microbiota which are necessary for normal intestinal barrier function. PMID:26528128

  12. Intestinal permeability of 51Cr-labelled ethylenediaminetetraacetic acid in patients with Crohn's disease and their healthy relatives

    International Nuclear Information System (INIS)

    Ainsworth, M.; Eriksen, J.; Rasmussen, J.W.; Muckadell, O.B.S. de

    1989-01-01

    An increased intestinal permeability has been proposed as an aetiologic factor in Crohn's disease. The 24-h urinary excretion of 100 μCi 51 Cr-labelled ethylenediaminetetraacetic acid (EDTA) was used to test the permeability in 15 patients with Crohn's disease and in 20 healthy first-degree relatives, who were known to have a genetic predisposition to inflammatory bowel disease. Twenty-eight healthy persons not related to patients with inflammatory bowel disease served as control material. The 51 Cr-EDTA excretion of the relatives was not significantly higher than that of the controls, whereas patients with Crohn's disease had a significantly higher excretion than both the relatives and the controls. Among patients the increased excretion was found only if the small intestine was involved. It is concluded that 1) as a group, patient with Crohn's disease in the small intestine have an increased intestinal permeability, in contrast to their healthy relatives, who have a normal permeability; 2) a considerable overlap of the results of the 51 Cr-EDTA test was found between the groups studied, and the test is not suitable for evaluating individual patients; 3) the results do not support the hypothesis of an increase in intestinal permeability as an aetiologic factor in Crohn's disease. 29 refs

  13. Regional-dependent intestinal permeability and BCS classification: elucidation of pH-related complexity in rats using pseudoephedrine.

    Science.gov (United States)

    Fairstein, Moran; Swissa, Rotem; Dahan, Arik

    2013-04-01

    Based on its lower Log P value relative to metoprolol, a marker for the low/high-permeability (P(eff)) class boundary, pseudoephedrine was provisionally classified as BCS low-permeability compound. On the other hand, following oral administration, pseudoephedrine fraction dose absorbed (F(abs)) and systemic bioavailability approaches 100%. This represents a challenge to the generally recognized P(eff)-F(abs) correlation. The purpose of this study was to elucidate the underlying mechanisms behind the confusion in pseudoephedrine's BCS classification. Pseudoephedrine's BCS solubility class was determined, and its physicochemical properties and intestinal permeability were thoroughly investigated, both in vitro and in vivo in rats, considering the complexity of the whole of the small intestine. Pseudoephedrine was found to be unequivocally a high-solubility compound. All of the permeability studies revealed similar phenomenon; at any given intestinal segment/pH, the permeability of metoprolol was higher than that of pseudoephedrine, however, as the intestinal region becomes progressively distal, and the pH gradually increases, pseudoephedrine's permeability rises above that of metoprolol in the former segment. This unique permeability pattern likely explains pseudoephedrine's complete absorption. In conclusion, pseudoephedrine is a BCS Class I compound; no discrepancy between P(eff) and F(abs) is involved in its absorption. Rather, it reflects the complexity behind P(eff) when considering the whole of the intestine. We propose to allow high-permeability classification to drugs with P(eff) that matches/exceeds the low/high class benchmark anywhere throughout the intestinal tract and not restricted necessarily to the jejunum.

  14. Experimental study of heavy oil-water flow structure effects on relative permeabilities in a fracture filled with heavy oil

    Energy Technology Data Exchange (ETDEWEB)

    Shad, S.; Gates, I.D.; Maini, B.B. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering]|[Alberta Ingenuity Centre for In Situ Energy, Edmonton, AB (Canada)

    2008-10-15

    An experimental apparatus was used to investigate the flow of water in the presence of heavy oil within a smooth-walled fracture. Different flow patterns were investigated under a variety of flow conditions. Results of the experiments were used to determine the accuracy of VC, Corey, and Shad and Gates models designed to represent the behaviour of oil wet systems. The relative permeability concept was used to describe the behaviour of multiple phases flowing through porous media. A smooth-walled plexiglass Hele-Shaw cell was used to visualize oil and water flow. Changes in flow rates led to different flow regimes. The experiment demonstrated that water flowed co-currently in the form of droplets or slugs. Decreases in the oil flow rate enlarged the size of the water droplets as well as the velocity, until eventually the droplets coalesced and became water slugs. Droplet appearance or disappearance directly impacted the oil and water saturation levels. Changes in fluid saturation altered the pressure gradient. Darcy's law for the 2 liquid phases were used to calculate relative permeability curves. The study showed that at low water saturation, oil relative permeability reached as high as 2.5, while water relative permeability was lower than unity. In the presence of a continuous water channel, water drops formed in oil, and the velocity of the drops was lower than their velocity under a discontinuous water flow regime. It was concluded that the Shad and Gates model overestimated oil relative permeability and underestimated water relative permeability. 38 refs., 2 tabs., 9 figs.

  15. Evaluation of the Membrane Permeability (PAMPA and Skin) of Benzimidazoles with Potential Cannabinoid Activity and their Relation with the Biopharmaceutics Classification System (BCS)

    OpenAIRE

    Alvarez-Figueroa, M. Javiera; Pessoa-Mahana, C. David; Palavecino-González, M. Elisa; Mella-Raipán, Jaime; Espinosa-Bustos, Cristián; Lagos-Muñoz, Manuel E.

    2011-01-01

    The permeability of five benzimidazole derivates with potential cannabinoid activity was determined in two models of membranes, parallel artificial membrane permeability assay (PAMPA) and skin, in order to study the relationship of the physicochemical properties of the molecules and characteristics of the membranes with the permeability defined by the Biopharmaceutics Classification System. It was established that the PAMPA intestinal absorption method is a good predictor for classifying thes...

  16. Relationship between micro-porosity, water permeability and mechanical behavior in scaffolds for cartilage engineering.

    Science.gov (United States)

    Vikingsson, L; Claessens, B; Gómez-Tejedor, J A; Gallego Ferrer, G; Gómez Ribelles, J L

    2015-08-01

    In tissue engineering the design and optimization of biodegradable polymeric scaffolds with a 3D-structure is an important field. The porous scaffold provide the cells with an adequate biomechanical environment that allows mechanotransduction signals for cell differentiation and the scaffolds also protect the cells from initial compressive loading. The scaffold have interconnected macro-pores that host the cells and newly formed tissue, while the pore walls should be micro-porous to transport nutrients and waste products. Polycaprolactone (PCL) scaffolds with a double micro- and macro-pore architecture have been proposed for cartilage regeneration. This work explores the influence of the micro-porosity of the pore walls on water permeability and scaffold compliance. A Poly(Vinyl Alcohol) with tailored mechanical properties has been used to simulate the growing cartilage tissue inside the scaffold pores. Unconfined and confined compression tests were performed to characterize both the water permeability and the mechanical response of scaffolds with varying size of micro-porosity while volume fraction of the macro-pores remains constant. The stress relaxation tests show that the stress response of the scaffold/hydrogel construct is a synergic effect determined by the performance of the both components. This is interesting since it suggests that the in vivo outcome of the scaffold is not only dependent upon the material architecture but also the growing tissue inside the scaffold׳s pores. On the other hand, confined compression results show that compliance of the scaffold is mainly controlled by the micro-porosity of the scaffold and less by hydrogel density in the scaffold pores. These conclusions bring together valuable information for customizing the optimal scaffold and to predict the in vivo mechanical behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. A casting and imaging technique for determining void geometry and relative permeability behavior of a single fracture specimen

    Energy Technology Data Exchange (ETDEWEB)

    Cox, B.L.; Pruess, K.; Persoff, P.

    1990-01-01

    A casting technique has been developed for making translucent replicas of the void space of natural rock fractures. Attenuation of light shined through the cast combined with digital image analysis provides a pointwise definition of fracture apertures. The technique has been applied to a fracture specimen from Dixie Valley, Nevada, and the measured void space geometry has been used to develop theoretical predictions of two-phase relative permeability. A strong anisotropy in relative permeabilities has been found, which is caused by highly anisotropic spatial correlations among fracture apertures. 16 refs., 6 figs.

  18. Relationship between intestinal permeability to [51Cr]EDTA and inflammatory activity in asymptomatic patients with Crohn's disease

    International Nuclear Information System (INIS)

    Pironi, L.; Miglioli, M.; Ruggeri, E.; Levorato, M.; Dallasta, M.A.; Corbelli, C.; Nibali, M.G.; Barbara, L.

    1990-01-01

    The relationship between intestinal permeability to an oral dose (100 mu Ci) of [51CR]EDTA and the inflammatory activity of Crohn's disease was studied in 63 adult patients (32 unresected and 31 resected) who underwent 162 evaluations. The results of the [51CR]EDTA test were compared with the serum levels of the acute-phase reactant proteins (APRP) and with the result of the [111In]leukocyte scanning, respectively, as an indirect and direct method to assess intestinal inflammation. In a group of healthy adult controls, the upper normal value for the 24-hr urinary [51CR]EDTA excretion was 3.61 (97.5% percentile) and the mean coefficient of variation was 21%. Sensitivity and specificity of the [51CR]EDTA test in identifying active inflammation expressed by increased serum levels of APRP were, respectively, 97% and 54% in the unresected group and 68% and 52% in the resected group of patients. The low specificity of the test was due to the presence of increased [51CR]EDTA urinary excretion in about half the cases with normal serum levels of APRP. The [111In]leukocyte scanning was performed in a subgroup of 11 patients (three unresected and eight resected) with normal serum levels of APRP, six with increased and five with normal [51CR]EDTA urinary excretion. All six patients with increased intestinal permeability had a positive 111In image of mild to moderate degree of activity. A positive 111In scan was present in two of the five patients with normal permeability; these were two resected patients

  19. Effect of temperature and relative humidity on the water vapour permeability and mechanical properties of cassava starch and soy protein concentrate based edible films.

    Science.gov (United States)

    Chinma, C E; Ariahu, C C; Alakali, J S

    2015-04-01

    The effect of temperature and relative humidity on the water vapour permeability (WVP) and mechanical properties of cassava starch and soy protein concentrate (SPC) based edible films containing 20 % glycerol level were studied. Tensile strength and elastic modulus of edible films increased with increase in temperature and decreased with increase in relative humidity, while elongation at break decreased. Water vapour permeability of the films increased (2.6-4.3 g.mm/m(2).day.kPa) with increase in temperature and relative humidity. The temperature dependence of water vapour permeation of cassava starch-soy protein concentrate films followed Arrhenius relationship. Activation energy (Ea) of water vapour permeation of cassava starch-soy protein concentrate edible films ranged from 1.9 to 5.3 kJ/mol (R (2)  ≥ 0.93) and increased with increase in SPC addition. The Ea values were lower for the bio-films than for polyvinylidene chloride, polypropylene and polyethylene which are an indication of low water vapour permeability of the developed biofilms compared to those synthetic films.

  20. The effect of pore-scale geometry and wettability on two-phase relative permeabilities within elementary cells

    Science.gov (United States)

    Bianchi Janetti, Emanuela; Riva, Monica; Guadagnini, Alberto

    2017-04-01

    We study the relative role of the complex pore space geometry and wettability of the solid matrix on the quantification of relative permeabilities characterizing steady state immiscible two-phase flow in porous media. We do so by considering elementary cells, which are typically employed in upscaling frameworks based on, e.g., homogenization or volume averaging. In this context one typically relies on the solution of pore-scale physics at a scale which is much smaller than that of an investigated porous system. Pressure-driven two-phase flow following simultaneous co-current injection of water and oil is numerically solved for a suite of regular and stochastically generated two-dimensional explicit elementary cells with fixed porosity and sharing main topological/morphological features. We show that relative permeabilities of the randomly generated elementary cells are significantly influenced by the formation of preferential percolation paths (principal pathways), giving rise to a strongly nonuniform distribution of fluid fluxes. These pathways are a result of the spatially variable resistance that the random pore structures exert on the fluid. The overall effect on relative permeabilities of the diverse organization of principal pathways, as driven by a given random realization at the scale of the unit cell, is significantly larger than that of the wettability of the host rock. In contrast to what can be observed for the random cells analyzed, relative permeabilities of regular cells display a clear trend with contact angle at the investigated scale. Our findings suggest the need to perform systematic upscaling studies in a stochastic context, to propagate the effects of uncertain pore space geometries to a probabilistic description of relative permeability curves at the continuum scale.

  1. Compositional and Relative Permeability Hysteresis Effects on Near-Miscible WAG

    DEFF Research Database (Denmark)

    Christensen, Jes Reimer; Stenby, Erling Halfdan; Skauge, Arne

    1998-01-01

    Evaluation of compositional effects and fluid flow description on near-miscible (water-alternating-gas) WAG modeling have been studied for a North Sea oil field starting production in 1998. A sector model with four wells was applied to simulate a heterogeneous sandstone reservoir, and a compositi......Evaluation of compositional effects and fluid flow description on near-miscible (water-alternating-gas) WAG modeling have been studied for a North Sea oil field starting production in 1998. A sector model with four wells was applied to simulate a heterogeneous sandstone reservoir......, and a compositional model was used to compare different production strategies e.g. waterflooding and a near-miscible (WAG) injection. In the WAG scheme both dry and wet (rich) hydrocarbon gases have been considered for injection. The phase behaviour was quantified by comparing the performance of the different...... injection gases. Result obtained shows the WAG injection gives improved recovery compared to water injection, due to better sweep and lower residual oil saturation. Simulations with and without relative permeability hysteresis (two-phase model) were compared. The effect of trapped gas on oil recovery does...

  2. Study of pressure drop, void fraction and relative permeabilities of two phase flow through porous media

    International Nuclear Information System (INIS)

    Chu, W.; Dhir, V.K.; Marshall, J.

    1983-01-01

    An experimental investigation of two phase flow through porous layers formed of non-heated glass particles (nominal diameter 1 to 6 mm) has been made. Particulate bed depths of 30 cm and 70 cm were used. The effect of particle size, particle size distribution and bed porosity on void fraction and pressure drop through a particulate bed formed in a cylindrical test section has been investigated. The superficial velocity of liquid (water) is varied from 1.83 to 18.3 mm/s while the superficial velocity of gas (air) is varied from 0 to 68.4 mm/s. These superficial velocities were chosen so that pressure drop and void fraction measurement could be made for the porous layer in fixed and fluidized states. A model based on drift flux approach has been developed for the void fraction. Using the two phase friction pressure drop data, the relative permeabilities of the two phases have been concluded with void fraction. The void fraction and two phase friction pressure gradient in beds composed of mixtures of spherical particles as well as sharps of different nominal sizes have also been examined. It is found that the models for single size particles are also applicable to mixtures of particles if a mean particle diameter for the mixture is defined

  3. Tomographic evidence for enhanced fracturing and permeability within the relatively aseismic Nemaha Fault Zone, Oklahoma

    Science.gov (United States)

    Stevens, N. T.; Keranen, K. M.; Lambert, C.

    2017-12-01

    Recent earthquakes in north central Oklahoma are dominantly hosted on unmapped basement faults away from and outside of the largest regional structure, the Nemaha Fault Zone (NFZ) [Lambert, 2016]. The NFZ itself remains largely aseismic, despite the presence of disposal wells and numerous faults. Here we present results from double-difference tomography using TomoDD [Zhang and Thurber, 2003] for the NFZ and the surrounding region, utilizing a seismic catalog of over 10,000 local events acquired by 144 seismic stations deployed between 2013 and 2017. Inversion results for shallow crustal depth, beneath the 2-3 km sedimentary cover, show compressional wavespeeds (Vp) of >6 km/sec and shear wavespeeds (Vs) >4 km/sec outside the NFZ, consistent with crystalline rock. Along the western margin of the NFZ, both Vp and Vs are reduced, and Vp/Vs gradients parallel the trend of major faults, suggesting enhanced fault density and potentially enhanced fluid pressure within the study region. Enhanced fracture density within the NFZ, and associated permeability enhancement, could reduce the effect of regional fluid pressurization from injection wells, contributing to the relative aseismicity of the NFZ.

  4. Relative permeabilities of supercritical CO2 and brine in carbon sequestration by a two-phase lattice Boltzmann method

    Science.gov (United States)

    Xie, Jian.-Fei.; He, S.; Zu, Y. Q.; Lamy-Chappuis, B.; Yardley, B. W. D.

    2017-08-01

    In this paper, the migration of supercritical carbon dioxide (CO2) in realistic sandstone rocks under conditions of saline aquifers, with applications to the carbon geological storage, has been investigated by a two-phase lattice Boltzmann method (LBM). Firstly the digital images of sandstone rocks were reproduced utilizing the X-ray computed microtomography (micro-CT), and high resolutions (up to 2.5 μm) were applied to the pore-scale LBM simulations. For the sake of numerical stability, the digital images were "cleaned" by closing the dead holes and removing the suspended particles in sandstone rocks. In addition, the effect of chemical reactions occurred in the carbonation process on the permeability was taken into account. For the wetting brine and non-wetting supercritical CO2 flows, they were treated as the immiscible fluids and were driven by pressure gradients in sandstone rocks. Relative permeabilities of brine and supercritical CO2 in sandstone rocks were estimated. Particularly the dynamic saturation was applied to improve the reliability of the calculations of the relative permeabilities. Moreover, the effects of the viscosity ratio of the two immiscible fluids and the resolution of digital images on the relative permeability were systematically investigated.

  5. Effect of Flow Direction on Relative Permeability Curves in Water/Gas Reservoir System: Implications in Geological CO2 Sequestration

    Directory of Open Access Journals (Sweden)

    Abdulrauf Rasheed Adebayo

    2017-01-01

    Full Text Available The effect of gravity on vertical flow and fluids saturation, especially when flow is against gravity, is not often a subject of interest to researchers. This is because of the notion that flow in subsurface formations is usually in horizontal direction and that vertical flow is impossible or marginal because of the impermeable shales or silts overlying them. The density difference between two fluids (usually oil and water flowing in the porous media is also normally negligible; hence gravity influence is neglected. Capillarity is also often avoided in relative permeability measurements in order to satisfy some flow equations. These notions have guided most laboratory core flooding experiments to be conducted in horizontal flow orientation, and the data obtained are as good as what the experiments tend to mimic. However, gravity effect plays a major role in gas liquid systems such as CO2 sequestration and some types of enhanced oil recovery techniques, particularly those involving gases, where large density difference exists between the fluid pair. In such cases, laboratory experiments conducted to derive relative permeability curves should take into consideration gravity effects and capillarity. Previous studies attribute directional dependence of relative permeability and residual saturations to rock anisotropy. It is shown in this study that rock permeability, residual saturation, and relative permeability depend on the interplay between gravity, capillarity, and viscous forces and also the direction of fluid flow even when the rock is isotropic. Rock samples representing different lithology and wide range of permeabilities were investigated through unsteady-state experiments covering drainage and imbibition in both vertical and horizontal flow directions. The experiments were performed at very low flow rates to capture capillarity. The results obtained showed that, for each homogeneous rock and for the same flow path along the core length

  6. PHYSICAL AND CHEMICAL PROPERTIES IN RELATION WITH SOIL PERMEABILITY IN THE AREA OF VELIKA GORICA WELL FIELD

    Directory of Open Access Journals (Sweden)

    Zoran Kovač

    2018-01-01

    Full Text Available Hydraulic parameters affects behaviour of various ions in soils. The goal of this paper was to get better understanding of relationship between physical and chemical properties and soil permeability at the location of case study profile Velika Gorica, based on the physical and chemical data. Soil profile is situated in the Eutric Cambisol of the Zagreb aquifer, Croatia. Zagreb aquifer represents the only source of potable water for inhabitants of the City of Zagreb and Zagreb County. Based on the data obtained from particle size analysis, soil hydraulic parameters and measured water content, unsaturated hydraulic conductivity values were calculated for the estimation of soil profile permeability. Soil water retention curves and unsaturated hydraulic conductivities are very similar for all depths because soil content does not change significantly through the depth. Determination of anions and cations on soil samples was performed using the method of ion chromatography. Results showed decrease of ions concentrations after 0.6 m depth. SAR distribution in the soil profile shows that SAR values are not significantly changing at the soil profile. The highest CEC and EC values are determined in horizon Bw developed in 0.6 m depth which is consistent with highest SAR value and ions concentrations. All results suggest that physical and chemical properties of investigated profile are in relationship with soil permeability.

  7. Hydrothermal alteration and permeability changes in granitic intrusions related to Sn-W deposits : case study of Panasqueira (Portugal)

    Science.gov (United States)

    Launay, Gaetan; Sizaret, Stanislas; Guillou-Frottier, Laurent; Gloaguen, Eric; Melleton, Jérémie; Pichavant, Michel; Champallier, Rémi; Pinto, Filipe

    2017-04-01

    The Panasqueira Sn-W deposit occurs as a dense network of flat wolframite and cassiterite-bearing quartz veins concentrated in the vicinity of a hidden greisen cupola, and to a lesser extent as disseminated cassiterites in the greisen. Previous studies (Thadeu 1951; 1979) have suggested that the Panasqueira deposit is genetically related to magmatic activity for which the most part is unexposed, and being only represented by the greisen cupola. Hydrothermal fluid circulation during the final stages of granite crystallisation has probably led to the greisenisation of the cupola followed by the deposition of the mineralization in the veins system. Mineral replacement reactions that occurred during the greisenisation could affect rock properties (porosity, density and permeability) which control fluid circulation in the granite. This study aims to investigate effects of greisenisation reactions on the dynamic (time varying) permeability that ultimately leads to fluid circulation in the greisen cupola. To do so, petrological study and experimental determinations of hydrodynamic features (porosity and permeability) for different granite alteration levels and petrographic types (unaltered granite to greisen) are combined and then integrated in coupled numerical models of fluid circulation around the granitic intrusion. Greisen occurs in the apical part of the granitic body and results in the pervasive alteration of the granite along the granite-schist contact. This greisen consists mainly of quartz and muscovite formed by the replacement of feldspars and bleaching of biotites of the initial granite. Otherwise, greisen is generally vuggy which suggests a porosity increase of the granite during hydrothermal alteration processes. This porosity increase has a positive effect on the permeability of the granitic system. Indeed, experimental measurements of permeability with the Paterson press indicate that the initial granite is impermeable (10-20 m2) whereas the greisen is

  8. Compact rock material gas permeability properties

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huanling, E-mail: whl_hm@163.com [Key Laboratory of Coastal Disaster and Defence, Ministry of Education, Hohai University, Nanjing 210098 (China); LML, University of Lille, Cite Scientifique, 59655 Villeneuve d’Ascq (France); Xu, Weiya; Zuo, Jing [Institutes of Geotechnical Engineering, Hohai University, Nanjing 210098 (China)

    2014-09-15

    Natural compact rocks, such as sandstone, granite, and rock salt, are the main materials and geological environment for storing underground oil, gas, CO{sub 2,} shale gas, and radioactive waste because they have extremely low permeabilities and high mechanical strengths. Using the inert gas argon as the fluid medium, the stress-dependent permeability and porosity of monzonitic granite and granite gneiss from an underground oil storage depot were measured using a permeability and porosity measurement system. Based on the test results, models for describing the relationships among the permeability, porosity, and confining pressure of rock specimens were analyzed and are discussed. A power law is suggested to describe the relationship between the stress-dependent porosity and permeability; for the monzonitic granite and granite gneiss (for monzonitic granite (A-2), the initial porosity is approximately 4.05%, and the permeability is approximately 10{sup −19} m{sup 2}; for the granite gneiss (B-2), the initial porosity is approximately 7.09%, the permeability is approximately 10{sup −17} m{sup 2}; and the porosity-sensitivity exponents that link porosity and permeability are 0.98 and 3.11, respectively). Compared with moderate-porosity and high-porosity rocks, for which φ > 15%, low-porosity rock permeability has a relatively lower sensitivity to stress, but the porosity is more sensitive to stress, and different types of rocks show similar trends. From the test results, it can be inferred that the test rock specimens’ permeability evolution is related to the relative particle movements and microcrack closure.

  9. Relative Impacts of Low Permeability Subsurface Deposits on Recharge Basin Infiltration Rates

    Science.gov (United States)

    Oconnell, P.; Becker, M.; Pham, C.; Rodriguez, G.; Hutchinson, A.; Plumlee, M.

    2017-12-01

    Artificial recharge of aquifers through spreading basins has become an important component of water management in semi-arid climates. The rate at which water can be recharged in these basins is limited by the natural vertical permeability of the underlying deposits which may be highly variable both laterally and vertically. To help understand hydrostratigraphic controls on recharge, a newly constructed basin was surveyed and instrumented. Prior to flooding the basin, lithology was characterized by shallow hand coring, direct push coring, ground penetrating radar, and electrical resistivity. After flooding, recharge was monitored through piezometers, electrical resistivity, and a network of fiber optic distributed temperature sensing (DTS). The DTS network used temperature as a tracer to measure infiltration rate on 25 cm intervals both laterally and vertically. Several hundred paired DTS time series datasets (from fiber optic cables located at 0 and 0.5 meters below ground surface) were processed with the cross-wavelet transform (XWT) to calculate spatially and temporally continuous infiltration rates, which can be interpolated and animated to visualize heterogeneity. Time series data from 8-meter deep, vertically oriented DTS cables reveal depth intervals where infiltration rates vary. Inverted resistivity sections from repeated dipole-dipole surveys along the sidewall of a spreading basin exhibit a positive correlation with the distribution of relatively high and low infiltration rates, indicating zones of preferential downward (efficient) and lateral (inefficient) flow, respectively. In contrast to other monitored basins, no perching was observed in the vertically oriented DTS cables. The variation in recharge across the basin and the appearance of subsurface lateral flow can be explained in context of the alluvial depositional environment.

  10. Evaluating the Influence of Pore Architecture and Initial Saturation on Wettability and Relative Permeability in Heterogeneous, Shallow-Shelf Carbonates

    Energy Technology Data Exchange (ETDEWEB)

    Byrnes, Alan P.; Bhattacharya, Saibal; Victorine, John; Stalder, Ken

    2007-09-30

    Thin (3-40 ft thick), heterogeneous, limestone and dolomite reservoirs, deposited in shallow-shelf environments, represent a significant fraction of the reservoirs in the U.S. midcontinent and worldwide. In Kansas, reservoirs of the Arbuckle, Mississippian, and Lansing-Kansas City formations account for over 73% of the 6.3 BBO cumulative oil produced over the last century. For these reservoirs basic petrophysical properties (e.g., porosity, absolute permeability, capillary pressure, residual oil saturation to waterflood, resistivity, and relative permeability) vary significantly horizontally, vertically, and with scale of measurement. Many of these reservoirs produce from structures of less than 30-60 ft, and being located in the capillary pressure transition zone, exhibit vertically variable initial saturations and relative permeability properties. Rather than being simpler to model because of their small size, these reservoirs challenge characterization and simulation methodology and illustrate issues that are less apparent in larger reservoirs where transition zone effects are minor and most of the reservoir is at saturations near S{sub wirr}. These issues are further augmented by the presence of variable moldic porosity and possible intermediate to mixed wettability and the influence of these on capillary pressure and relative permeability. Understanding how capillary-pressure properties change with rock lithology and, in turn, within transition zones, and how relative permeability and residual oil saturation to waterflood change through the transition zone is critical to successful reservoir management and as advanced waterflood and improved and enhanced recovery methods are planned and implemented. Major aspects of the proposed study involve a series of tasks to measure data to reveal the nature of how wettability and drainage and imbibition oil-water relative permeability change with pore architecture and initial water saturation. Focus is placed on

  11. Meteoric calcite cementation: diagenetic response to relative fall in sea-level and effect on porosity and permeability, Las Negras area, southeastern Spain

    Science.gov (United States)

    Li, Zhaoqi; Goldstein, Robert H.; Franseen, Evan K.

    2017-03-01

    A dolomitized Upper Miocene carbonate system in southeast Spain contains extensive upper and lower zones of calcite cementation that cut across the stratigraphy. Cement textures including isopachous and circumgranular, which are consistent with phreatic-zone cementation. Cements in the upper cemented zone are non-luminescent, whereas those in the lower cemented zone exhibit multiple bands of luminescent and non-luminescent cements. In the upper cemented zone, isotopic data show two meteoric calcite lines (MCL) with mean δ18O at - 5.1‰ and - 5.8‰ VPDB, whereas no clear MCL is defined in the lower cemented zone where mean δ18O for calcite cement is at - 6.7‰ VPDB. δ13C values in both cement zones are predominantly negative, ranging from - 10 to + 2‰ VPDB, suggestive of carbon from soil gas or decayed organics. Measurements of Tm ice in primary fluid inclusions yield a mode of 0.0 °C in both zones, indicating calcite cementation from fresh water. These two zones define the positions of two different paleo-water tables that formed during a relative sea-level fall and erosional downcutting during the Plio-Pleistocene. The upper cemented zone pre-dated the lower cemented zone on the basis of known relative sea-level history. Meteoric calcite cementation reduced porosity and permeability, but measured values are inconsistent with simple filling of open pore space. Each texture, boundstone, grainstone, packstone, wackestone, produces a different relationship between percent calcite cement and porosity/permeability. Distribution of cements may be predictable on the basis of known sea-level history, and the effect of the cementation can be incorporated into subsurface geomodels by defining surfaces of rock boundaries that separate cemented zones from uncemented zones, and applying texture-specific relationships among cementation, porosity and permeability.

  12. Theoretical Insight Into the Empirical Tortuosity-Connectivity Factor in the Burdine-Brooks-Corey Water Relative Permeability Model

    Science.gov (United States)

    Ghanbarian, Behzad; Ioannidis, Marios A.; Hunt, Allen G.

    2017-12-01

    A model commonly applied to the estimation of water relative permeability krw in porous media is the Burdine-Brooks-Corey model, which relies on a simplified picture of pores as a bundle of noninterconnected capillary tubes. In this model, the empirical tortuosity-connectivity factor is assumed to be a power law function of effective saturation with an exponent (μ) commonly set equal to 2 in the literature. Invoking critical path analysis and using percolation theory, we relate the tortuosity-connectivity exponent μ to the critical scaling exponent t of percolation that characterizes the power law behavior of the saturation-dependent electrical conductivity of porous media. We also discuss the cause of the nonuniversality of μ in terms of the nonuniversality of t and compare model estimations with water relative permeability from experiments. The comparison supports determining μ from the electrical conductivity scaling exponent t, but also highlights limitations of the model.

  13. INTESTINAL PERMEABILITY IN PATIENTS WITH CELIAC-DISEASE AND RELATIVES OF PATIENTS WITH CELIAC-DISEASE

    NARCIS (Netherlands)

    van Elburg, R. M.; Uil, J. J.; Mulder, C. J.; Heymans, H. S.

    1993-01-01

    The functional integrity of the small bowel is impaired in coeliac disease. Intestinal permeability, as measured by the sugar absorption test probably reflects this phenomenon. In the sugar absorption test a solution of lactulose and mannitol was given to the fasting patient and the

  14. INTESTINAL PERMEABILITY IN PATIENTS WITH CELIAC-DISEASE AND RELATIVES OF PATIENTS WITH CELIAC-DISEASE

    NARCIS (Netherlands)

    VANELBURG, RM; UIL, JJ; MULDER, CJJ; HEYMANS, HSA

    The functional integrity of the small bowel is impaired in coeliac disease. Intestinal permeability, as measured by the sugar absorption test probably reflects this phenomenon. In the sugar absorption test a solution of lactulose and mannitol was given to the fasting patient and the

  15. Literature review and recommendation of methods for measuring relative permeability of anhydrite from the Salado Formation at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, R.L. [Colorado School of Mines, Golden, CO (United States). Dept. of Petroleum Engineering; Howarth, S.M. [Sandia National Labs., Albuquerque, NM (United States)

    1995-08-01

    This report documents a literature review of methods for measuring relative permeability as applied to low permeability anhydrite rock samples from the Salado Formation. About one hundred papers were reviewed, and four methods were identified as promising techniques for measuring the relative permeability of the Salado anhydrite: (1) the unsteady-state high-rate method, (2) the unsteady-state stationary-liquid method, (3) the unsteady-state centrifuge method, and (4) the unsteady-state low-rate method. Except for the centrifuge method, all have been used for low permeability rocks. The unsteady-state high-rate method is preferred for measuring relative permeability of Salado anhydrite, and the unsteady-state stationary-liquid method could be well suited for measuring gas relative permeability of Salado anhydrite. The unsteady-state low-rate method, which combines capillary pressure effects with relative permeability concepts may also prove effective. Likewise, the unsteady-state centrifuge method may be an efficient means for measuring brine relative permeability for Salado anhydrite, especially at high gas saturations.

  16. Literature review and recommendation of methods for measuring relative permeability of anhydrite from the Salado Formation at the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Christiansen, R.L.

    1995-08-01

    This report documents a literature review of methods for measuring relative permeability as applied to low permeability anhydrite rock samples from the Salado Formation. About one hundred papers were reviewed, and four methods were identified as promising techniques for measuring the relative permeability of the Salado anhydrite: (1) the unsteady-state high-rate method, (2) the unsteady-state stationary-liquid method, (3) the unsteady-state centrifuge method, and (4) the unsteady-state low-rate method. Except for the centrifuge method, all have been used for low permeability rocks. The unsteady-state high-rate method is preferred for measuring relative permeability of Salado anhydrite, and the unsteady-state stationary-liquid method could be well suited for measuring gas relative permeability of Salado anhydrite. The unsteady-state low-rate method, which combines capillary pressure effects with relative permeability concepts may also prove effective. Likewise, the unsteady-state centrifuge method may be an efficient means for measuring brine relative permeability for Salado anhydrite, especially at high gas saturations

  17. Asbestosis. Bronchoalveolar lavage fluid proteins and their relationship to pulmonary epithelial permeability

    International Nuclear Information System (INIS)

    Gellert, A.R.; Perry, D.; Langford, J.A.; Riches, P.G.; Rudd, R.M.

    1985-01-01

    The authors measured levels of albumin and immunoglobulins in serum and bronchoalveolar lavage (BAL) fluid in 28 men with asbestosis and 11 control subjects. The half-time clearance of inhaled diethylene triamine pentacetate labelled with technetium-99m (/sup 99m/Tc-DTPA) from the lungs (t1/2LB) was measured in 26 patients with asbestosis and in 31 normal nonsmoking controls. In those individuals in whom immunoglobulins were detected in BAL fluid, the mean IgG:albumin ratio in BAL fluid was 0.30, significantly less than the ratio of 0.43 in control subjects. There was no significant difference in IgA:albumin ratios between patients and control subjects. The mean BAL:serum albumin ratio in patients with asbestosis was 2.3 X 10(-3). The t1/2LB was significantly shorter in both smokers and nonsmokers with asbestosis, compared with 31 normal nonsmoking controls, but there were no relationships between t1/2LB and BAL:serum albumin ratio or any other BAL protein levels in either smokers or nonsmokers with asbestosis

  18. Interleukin-6 in CAPD patients without peritonitis: relationship to the intrinsic permeability of the peritoneal membrane

    NARCIS (Netherlands)

    Zemel, D.; ten Berge, R. J.; Struijk, D. G.; Bloemena, E.; Koomen, G. C.; Krediet, R. T.

    1992-01-01

    We investigated whether day to day changes in the transport characteristics of the peritoneal membrane to macromolecules in patients treated with CAPD, were related to the levels of interleukin-6 (IL-6) in the effluent of an overnight dwell. Four stable CAPD patients without peritonitis collected

  19. Relative Power in Sibling Relationships Across Adolescence.

    Science.gov (United States)

    Lindell, Anna K; Campione-Barr, Nicole

    2017-06-01

    During childhood, older siblings typically hold a more powerful position in their relationship with their younger siblings, but these relationships are thought to become more egalitarian during adolescence as siblings begin to prepare for their relationships as adults and as younger siblings become more socially and cognitively competent. Little is known about relationship factors that may explain this shift in power dynamics, however. The present study therefore examined longitudinal changes in adolescents' and their siblings' perceptions of sibling relative power from age 12 to 18 (n = 145 dyads), and examined whether different levels of sibling relationship positivity and negativity, as well as sibling structural variables, indicated different over-time changes in relative power. Multilevel models indicated that adolescents reported significant declines in their siblings' relative power across adolescence, with older siblings relinquishing the most power over time. However, only siblings with less positively involved relationships reported declines in relative power, suggesting that siblings who maintain highly involved relationships may not become more egalitarian during adolescence. © 2017 Wiley Periodicals, Inc.

  20. Perovskite-related oxide materials for oxygen-permeable electrochemical membrans

    OpenAIRE

    Naumovich, E. N.; Yaremchenko, A. A.; Viskup, A. P.; Kharton, V. V.

    2003-01-01

    This brief review is focused on the studies of mixed ionic-electronic conductors on the basis of lanthanum gallate doped with transition metal cations in the В sublattice. The substitution of gallium with iron, cobalt or nickel results in greater electronic conductivity, simultaneously keeping high level of the oxy-gen ionic transport. In particular, La0 90Sr0 10Ga0 65Ni0 20Mg0 1503d perovskite exhib-its attractive oxygen permeability, which is quite similar to that of La2Ni04- and (...

  1. Measurement of choroid plexus perfusion using dynamic susceptibility MR imaging: capillary permeability and age-related changes

    Energy Technology Data Exchange (ETDEWEB)

    Bouzerar, Roger; Chaarani, Bader; Baledent, Olivier [University Hospital, Image Processing Department, Amiens (France); Gondry-Jouet, Catherine [University Hospital, Radiology Department, Amiens (France); Zmudka, Jadwiga [University Hospital, Geriatric Unit, Amiens (France)

    2013-12-15

    The cerebrospinal fluid (CSF) plays a major role in the physiology of the central nervous system. The continuous turnover of CSF is mainly attributed to the highly vascularized choroid plexus (CP) located in the cerebral ventricles which represent a complex interface between blood and CSF. We propose a method for evaluating CP functionality in vivo using perfusion MR imaging and establish the age-related changes of associated parameters. Fifteen patients with small intracranial tumors were retrospectively studied. MR Imaging was performed on a 3T MR Scanner. Gradient-echo echo planar images were acquired after bolus injection of gadolinium-based contrast agent (CA). The software developed used the combined T1- and T2-effects. The decomposition of the relaxivity signals enables the calculation of the CP capillary permeability (K{sub 2}). The relative cerebral blood volume (rCBV), mean transit time (MTT), and signal slope decrease (SSD) were also calculated. The mean permeability K{sub 2} of the extracted CP was 0.033+/-0.18 s{sup -1}. K{sub 2} and SSD significantly decreased with subject's age whereas MTT significantly increased with subject's age. No significant correlation was found for age-related changes in rCBV and rCBF. The decrease in CP permeability is in line with the age-related changes in CSF secretion observed in animals. The MTT increase indicates significant structural changes corroborated by microscopy studies in animals or humans. Overall, DSC MR-perfusion enables an in vivo evaluation of the hemodynamic state of CP. Clinical applications such as neurodegenerative diseases could be considered thanks to specific functional studies of CP. (orig.)

  2. Crustal permeability

    Science.gov (United States)

    Gleeson, Tom; Ingebritsen, Steven E.

    2016-01-01

    Permeability is the primary control on fluid flow in the Earth’s crust and is key to a surprisingly wide range of geological processes, because it controls the advection of heat and solutes and the generation of anomalous pore pressures.  The practical importance of permeability – and the potential for large, dynamic changes in permeability – is highlighted by ongoing issues associated with hydraulic fracturing for hydrocarbon production (“fracking”), enhanced geothermal systems, and geologic carbon sequestration.  Although there are thousands of research papers on crustal permeability, this is the first book-length treatment.  This book bridges the historical dichotomy between the hydrogeologic perspective of permeability as a static material property and the perspective of other Earth scientists who have long recognized permeability as a dynamic parameter that changes in response to tectonism, fluid production, and geochemical reactions. 

  3. Problems of increasing of thermostability of highly permeable Ni-Zn ferrites and relative materials for telecommunications

    Energy Technology Data Exchange (ETDEWEB)

    Gonchar, A. E-mail: letyuk@mail.ru; Andreev, V.; Letyuk, L.; Shishkanov, A.; Maiorov, V

    2003-01-01

    The work considers ways of increasing of thermostability of ferrites of the basic systems NiO-ZnO-Fe{sub 2}O{sub 3} and MgO-ZnO-Fe{sub 2}O{sub 3} and relative materials for telecommunication. Sufficient results in increasing of the thermostability were achieved by doping Cu ions and controlling rejection of Fe{sub 2}O{sub 3} content from equimolar composition. These results allow to increase the Curie temperature to 130-140 deg. C for Ni-Zn ferrites with initial permeability 2000.

  4. Notional Permeability

    NARCIS (Netherlands)

    Kik, R.; Van den Bos, J.P.; Maertens, J.; Verhagen, H.J.; Van der Meer, J.W.

    2012-01-01

    Different layer design of a rock slope and under layers has a large effect on the strengths on the rock slope itself. In the stability formula developed of VAN DER MEER [1988] this effect is represented by the term Notional Permeability with symbol P. A more open, or permeable, structure underneath

  5. Relative rates of albumin equilibration in the skin interstitium and lymph during increased permeability

    International Nuclear Information System (INIS)

    Powers, M.R.; Wallace, J.R.; Bell, D.R.

    1986-01-01

    The initial equilibration of 125 I-labelled albumin between the vascular and extravascular compartments was studied in hindpaw heel skin of anesthetized rabbits. Bradykinin (0.3 μg/min) was infused into a small branch of the femoral artery. A second group of rabbits served as control. Following bradykinin, prenodal popliteal lymph flow was 4 times control flow. The lymph-to-plasma concentration ratios for total protein and albumin were, respectively, 60% and 50% larger than control. Tissue albumin concentration was twice control. After reaching a steady, elevated lymph flow, tracer albumin was infused to maintain plasma activity constant for 3 hrs. The plasma volume in tissue samples was measured using 131 I-labeled albumin injected 10 min before ending the experiment. Endogenous albumin was measured in plasma, lymph, and tissue samples using rocket electroimmunoassay. After 3 hrs of tracer infusion, lymph specific activity was 3 times greater than control. In the control group, plasma albumin equilibrated more rapidly with lymph than with tissue (p < 0.05). Following bradykinin, extravascular specific activity was 4 times control, resulting in lymph and tissue equilibrating with plasma at similar rates. Thus, increasing capillary permeability causes the extravascular albumin mass to behave as if distributed in a single compartment

  6. Permeability of porour rhyolite

    Science.gov (United States)

    Cashman, K.; Rust, A.; Wright, H.; Roberge, J.

    2003-04-01

    The development of permeability in bubble-bearing magmas determines the efficiency of volatile escape during their ascent through volcanic conduits, which, in turn, controls their explosive potential. As permeability requires bubble connectivity, relationships between permeability and porosity in silicic magmas must be controlled by the formation, growth, deformation and coalescence of their constituent bubbles. Although permeability data on porous volcanic pyroclasts are limited, the database can be greatly extended by including data for ceramic and metallic foams1. Several studies indicate that a single number does not adequately describe the permeability of a foam because inertial effects, which predominate at high flow rates, cause deviations from Darcy's law. These studies suggest that permeability is best modeled using the Forschheimer equation to determine both the Darcy permeability (k1) and the non-Darcian (k2) permeability. Importantly, at the high porosities of ceramic foams (75-95%), both k1 and k2 are strongly dependent on pore size and geometry, suggesting that measurement of these parameters provides important information on foam structure. We determined both the connected porosity (by He-pycnometry) and the permeability (k1 and k2) of rhyolitic samples having a wide range in porosity (22-85%) and vesicle textures. In general, these data support previous observations of a power law relationship between connected porosity and Darcy permeability2. In detail, variations in k1 increase at higher porosities. Similarly, k2 generally increases in both mean and standard deviation with increasing porosity. Measurements made on three mutually perpendicular cores from individual pumice clasts suggest that some of the variability can be explained by anisotropy in the vesicle structure. By comparison with ceramic foams, we suggest that the remaining variability results from differences either in average vesicle size or, more likely, in the size of apertures

  7. Direct numerical simulation of supercritical gas flow in complex nanoporous media: Elucidating the relationship between permeability and pore space geometry

    Science.gov (United States)

    Landry, C. J.; Prodanovic, M.; Eichhubl, P.

    2015-12-01

    Mudrocks and shales are currently a significant source of natural gas and understanding the basic transport properties of these formations is critical to predicting long-term production, however, the nanoporous nature of mudrocks presents a unique challenge. Mudrock pores are predominantly in the range of 1-100 nm, and within this size range the flow of gas at reservoir conditions will fall within the slip-flow and early transition-flow regime (0.001 clays). Here we present a local effective viscosity lattice Boltzmann model (LEV-LBM) constructed for flow simulation in the slip- and early-transition flow regimes, adapted here for complex geometries. At the macroscopic scale the LEV-LBM is parameterized with local effective viscosities at each node to capture the variance of the mean free path of gas molecules in a bounded system. The LEV-LBM is first validated in simple tube geometries, where excellent agreement with linearized Boltzmann solutions is found for Knudsen numbers up to 1.0. The LEV-LBM is then employed to quantify the length effect on the apparent permeability of tubes, which suggests pore network modeling of flow in the slip and early-transition regime will result in overestimation unless the length effect is considered. Furthermore, the LEV-LBM is used to evaluate the predictive value of commonly measured pore geometry characteristics such as porosity, pore size distribution, and specific solid surface area for the calculation of permeability. We show that bundle of tubes models grossly overestimate apparent permeability, as well as underestimate the increase in apparent permeability with decreasing pressure as a result of excluding topology and pore shape from calculations.

  8. Pore Structure and Diagenetic Controls on Relative Permeability: Implications for Enhanced Oil Recovery and CO2 Storage

    Science.gov (United States)

    Feldman, J.; Dewers, T. A.; Heath, J. E.; Cather, M.; Mozley, P.

    2016-12-01

    Multiphase flow in clay-bearing sandstones of the Morrow Sandstone governs the efficiency of CO2 storage and enhanced oil recovery at the Farnsworth Unit, Texas. This formation is the target for enhanced oil recovery and injection of one million metric ton of anthropogenically-sourced CO2. The sandstone hosts eight major flow units that exhibit distinct microstructural characteristics due to diagenesis, including: "clean" macro-porosity; quartz overgrowths constricting some pores; ghost grains; intergranular porosity filled by microporous authigenic clay; and feldspar dissolution. We examine the microstructural controls on macroscale (core scale) relative permeability and capillary pressure behavior through: X-ray computed tomography, Robomet.3d, and focused ion beam-scanning electron microscopy imaging of the pore structure of the major flow units of the Morrow Sandstone; relative permeability and capillary pressure in the laboratory using CO2, brine, and oil at reservoir pressure and effective stress conditions. The combined data sets inform links between patterns of diagenesis and multiphase flow. These data support multiphase reservoir simulation and performance assessment by the Southwest Regional Partnership on Carbon Sequestration (SWP). Funding for this project is provided by the U.S. Department of Energy's National Energy Technology Laboratory through the SWP under Award No. DE-FC26-05NT42591. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  9. Gut permeability is related to body weight, fatty liver disease, and insulin resistance in obese individuals undergoing weight reduction.

    Science.gov (United States)

    Damms-Machado, Antje; Louis, Sandrine; Schnitzer, Anna; Volynets, Valentina; Rings, Andreas; Basrai, Maryam; Bischoff, Stephan C

    2017-01-01

    Obesity and associated metabolic disorders are related to impairments of the intestinal barrier. We examined lactulose:mannitol (Lac:Man) permeability in obese individuals with and without liver steatosis undergoing a weight-reduction program to test whether an effective weight-loss program improves gut barrier function and whether obese patients with or without liver steatosis differ in this function. Twenty-seven adult, nondiabetic individuals [mean ± SD body mass index (BMI; in kg/m 2 ): 43.7 ± 5.2; 78% with moderate or severe liver steatosis] were included in the follow-up intervention study (n = 13 by month 12). All patients reduced their weight to a mean ± SD BMI of 36.4 ± 5.1 within 12 mo. We assessed barrier functions by the oral Lac:Man and the fecal zonulin tests. Insulin resistance was assessed by the homeostatic model assessment index (HOMA), and liver steatosis by sonography and the fatty liver index (FLI). The Lac:Man ratio and circulating interleukin (IL) 6 concentration decreased during intervention from 0.080 (95% CI: 0.073, 0.093) to 0.027 (95% CI: 0.024, 0.034; P < 0.001) and from 4.2 ± 1.4 to 2.8 ± 1.6 pg/mL (P < 0.01), respectively. At study start, the Lac:Man ratio was higher in patients with moderate or severe steatosis than in those without any steatosis (P < 0.001). The Lac:Man ratio tended to correlate with HOMA (ρ = 0.55, P = 0.052), which correlated with FLI (ρ = 0.75, P < 0.01). A multiple-regression analysis led to a final model explaining FLI best through BMI, waist circumference, and the Lac:Man ratio. Intestinal permeability is increased in obese patients with steatosis compared with obese patients without. The increased permeability fell to within the previously reported normal range after weight reduction. The data suggest that a leaky gut barrier is linked with liver steatosis and could be a new target for future steatosis therapies. This trial was registered at clinicaltrials.gov as NCT01344525. © 2017 American Society

  10. Unexpected effects of peripherally administered kynurenic acid on cortical spreading depression and related blood–brain barrier permeability

    Directory of Open Access Journals (Sweden)

    Oláh G

    2013-09-01

    Full Text Available Gáspár Oláh,1 Judit Herédi,1 Ákos Menyhárt,1 Zsolt Czinege,2 Dávid Nagy,1 János Fuzik,1 Kitti Kocsis,1 Levente Knapp,1 Erika Krucsó,1 Levente Gellért,1 Zsolt Kis,1 Tamás Farkas,1 Ferenc Fülöp,3 Árpád Párdutz,4 János Tajti,4 László Vécsei,4 József Toldi1 1Department of Physiology, Anatomy and Neuroscience, 2Department of Software Engineering, 3Institute of Pharmaceutical Chemistry and MTA-SZTE Research Group for Stereochemistry, 4Department of Neurology and MTA-SZTE Neuroscience Research Group, University of Szeged, Szeged, Hungary Abstract: Cortical spreading depression (CSD involves a slowly-propagating depolarization wave in the cortex, which can appear in numerous pathophysiological conditions, such as migraine with aura, stroke, and traumatic brain injury. Neurons and glial cells are also depolarized transiently during the phenomena. CSD is followed by a massive increase in glutamate release and by changes in the brain microcirculation. The aim of this study was to investigate the effects of two N-methyl-D-aspartate receptor antagonists, endogenous kynurenic acid (KYNA and dizocilpine, on CSD and the related blood–brain barrier (BBB permeability in rats. In intact animals, KYNA hardly crosses the BBB but has some positive features as compared with its precursor L-Kynurenine, which is frequently used in animal studies (KYNA cannot be metabolized to excitotoxic agents such as 3-hydroxy-L-kynurenine and quinolinic acid. We therefore investigated the possible effects of peripherally administered KYNA. Repetitive CSD waves were elicited by the application of 1 M KCl solution to the cortex. Direct current-electrocorticograms were measured for 1 hour. Four parameters of the waves were compared. Evans blue dye and fluorescent microscopy were used to study the possible changes in the permeability of the BBB. The results demonstrated that N-methyl-D-aspartate receptor antagonists can reduce the number of CSD waves and decrease

  11. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to flaxseed oil and vitamin E and maintenance of the skin permeability barrier function pursuant to Article 13(5) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Tetens, Inge

    related to a combination of flaxseed oil and vitamin E and maintenance of the skin permeability barrier function. The food constituent that is the subject of the health claim is a combination of flaxseed oil and vitamin E. The Panel considers that the combination of flaxseed oil and vitamin E...... be drawn from these studies for the scientific substantiation of the claim. The Panel concludes that a cause and effect relationship has not been established between the consumption of a combination of flaxseed oil and vitamin E and maintenance of the skin permeability barrier function...... is sufficiently characterised. The claimed effect is “contributes to maintain skin permeability barrier function”. The target population proposed by the applicant is healthy adults with dry and sensitive skin. Maintenance of the permeability barrier function of the skin is a beneficial physiological effect...

  12. Compression characteristics and permeability of saturated Gaomiaozi ca-bentonite

    International Nuclear Information System (INIS)

    Sun Wenjing; Sun De'an; Fang Lei

    2012-01-01

    The compression characteristics and permeability of compacted Gaomiaozi Ca-bentonite saturated by the water uptake tests are studied by conducting a series of one-dimension compression tests. The permeability coefficient can be calculated by the Terzaghi's one-dimensional consolidation theory after the consolidation coefficient is obtained by the square root of time method. It is found that the compression curves of compacted specimens saturated by the water uptake tests tend to be consistent in the relatively high stress range. The compression indexes show a linear decrease with increasing dry density and the swelling index is a constant. The permeability coefficient decreases with increasing compression stress, and they show the linear relationship in double logarithmic coordinates. Meanwhile, the permeability coefficient shows a linear decrease with decreasing void ratio, which has no relationship with initial states, stress states and stress paths. The permeability coefficient k of GMZ Ca-bentonite at dry density Pd of 1.75 g/cm 3 can be calculated as 2.0 × 10 -11 cm/s by the linear relationship between Pd and log k. It is closed to the permeability coefficient of GMZ Ca-bentonite with the same dry density published in literature, which testifies that the method calculating the permeability coefficient is feasible from the consolidation coefficient obtained by the consolidation test. (authors)

  13. Relative Power in Sibling Relationships across Adolescence

    Science.gov (United States)

    Lindell, Anna K.; Campione-Barr, Nicole

    2017-01-01

    During childhood, older siblings typically hold a more powerful position in their relationship with their younger siblings, but these relationships are thought to become more egalitarian during adolescence as siblings begin to prepare for their relationships as adults and as younger siblings become more socially and cognitively competent. Little…

  14. Intestinal Permeability: The Basics

    Directory of Open Access Journals (Sweden)

    Ingvar Bjarnason

    1995-01-01

    Full Text Available The authors review some of the more fundamental principles underlying the noninvasive assessment of intestinal permeability in humans, the choice of test markers and their analyses, and the practical aspects of test dose composition and how these can be changed to allow the specific assessment of regional permeability changes and other intestinal functions. The implications of increased intestinal permeability in the pathogenesis of human disease is discussed in relation to findings in patients with Crohn’s disease. A common feature of increased intestinal permeability is the development of a low grade enteropathy, and while quantitatively similar changes may be found in Crohn’s disease these seem to predict relapse of disease. Moreover, factors associated with relapse of Crohn’s disease have in common an action to increase intestinal permeability. While increased intestinal permeability does not seem to be important in the etiology of Crohn’s disease it may be a central mechanism in the clinical relapse of disease.

  15. Lover and learner: Exploring relational schema change following relationship dissolution.

    Science.gov (United States)

    Brunson, Julie A; Øverup, Camilla S; Acitelli, Linda K

    2018-03-27

    Romantic relationships are known to be very influential, but less is known about how these relationships, and particularly the breakup of these relationships, may affect individuals' relational schemas, or their expectations for relationships. Undergraduate students reported on how their views of themselves, romantic partners, and relationships changed after breaking up with a past partner. Results suggest that relational schemas change following relationship dissolution and that there are both positive and negative aspects to this change. There was also some evidence that aspects of the past relationship predicted change and the valence of change, and that change and the valence of change were related to aspects of current relationship quality. These results are an important first step in understanding how past romantic relationships influence people's expectations about relationships and, by extension, their health and wellbeing.

  16. Zonulin upregulation is associated with increased gut permeability in subjects with type 1 diabetes and their relatives.

    Science.gov (United States)

    Sapone, Anna; de Magistris, Laura; Pietzak, Michelle; Clemente, Maria G; Tripathi, Amit; Cucca, Francesco; Lampis, Rosanna; Kryszak, Deborah; Cartenì, Maria; Generoso, Maddalena; Iafusco, Dario; Prisco, Francesco; Laghi, Francesca; Riegler, Gabriele; Carratu, Romano; Counts, Debra; Fasano, Alessio

    2006-05-01

    Zonulin, a protein that modulates intestinal permeability, is upregulated in several autoimmune diseases and is involved in the pathogenesis of autoimmune diabetes in the BB/Wor animal model of the disease. To verify the association between serum zonulin levels and in vivo intestinal permeability in patients with type 1 diabetes, both parameters were investigated in different stages of the autoimmune process. Forty-two percent (141 of 339) of the patients had abnormal serum zonulin levels, as compared with age-matched control subjects. The increased zonulin levels correlated with increased intestinal permeability in vivo and changes in claudin-1, claudin-2, and myosin IXB genes expression, while no changes were detected in ZO1 and occludin genes expression. When tested in serum samples collected during the pre-type 1 diabetes phase, elevated serum zonulin was detected in 70% of subjects and preceded by 3.5 +/- 0.9 years the onset of the disease in those patients who went on to develop type 1 diabetes. Combined, these results suggest that zonulin upregulation is associated with increased intestinal permeability in a subgroup of type 1 diabetic patients. Zonulin upregulation seems to precede the onset of the disease, providing a possible link between increased intestinal permeability, environmental exposure to non-self antigens, and the development of autoimmunity in genetically susceptible individuals.

  17. Intestinal permeability to chromium-51 ethylenediamine tetraacetic acid in children with chronic obstructive respiratory disease: relationship with clinical and duodenal biopsy findings

    International Nuclear Information System (INIS)

    Hoyoux, C.; Forget, P.P.; Borlee-Hermans, G.; Geubelle, F.

    1988-01-01

    Intestinal permeability (IP) to 51 Cr ethylenediamine tetraacetic acid was investigated in 47 children with chronic obstructive respiratory disease (CORD). Endoscopic duodenal biopsies were performed in 22 of these patients. IP was significantly increased in CORD patients when compared to either control children or adults (P less than 0.001). Mean +/- 1 SD were 4.3 +/- 1.71%, 2.5 +/- 0.78%, and 2.3 +/- 0.77% in the three groups, respectively. IP was not related to the presence of atopy. Significant differences in IP results were found between CORD children with abdominal pain (4.5 +/- 1.4%) and both control children and CORD patients without abdominal pain (2.5 +/- 0.78% and 3.2 +/- 1.49%, respectively). A significant correlation was found between small bowel injury on the one hand and IP on the other hand (P less than 0.02). Furthermore, small bowel injury was significantly related to the presence of abdominal pain (P less than 0.05). We speculate that in CORD patients with abdominal pain, a factor exists that causes small bowel injury responsible for both abdominal pain and increased small bowel permeability. Food intolerance could, presumably, play a role in the mucosal damage-linked IP increase found in the subset of CORD patients who complain of abdominal pain

  18. An experimental study of relative permeability hysteresis, capillary trapping characteristics, and capillary pressure of CO2/brine systems at reservoir conditions

    Science.gov (United States)

    Akbarabadi, Morteza

    a consequence the Swi, then it was followed by the imbibition process to measure SCO2r. We performed different cycles of relative permeability experiments to investigate the effect of hysteresis. The Swi and SCO2r varied from 0.525 to 0.90 and 0.34 to 0.081, respectively. Maximum CO2 and brine relative permeabilities at the end of drainage and imbibition and also variation of brine relative permeability due to post-imbibition CO2 dissolution during unsteady-state experiment were also studied. We co-injected SO2 with CO2 and brine into the Madison limestone core sample. The sample was acquired from the Rock Springs Uplift in southwest Wyoming. The temperature and pressure of the experiments were 60°C and 19.16 MPa, respectively. Each drainage-imbibition cycle was followed by a dissolution process to establish Sw=1. The results showed that about 76% of the initial CO2 was trapped by capillary trapping mechanism at the end of imbibition test. We also investigated the scCO2+SO2/brine capillary pressure versus saturation relationship through performing primary drainage, imbibition, and secondary drainage experiments. The results indicated that the wettability of the core sample might have been altered owing to being in contact with the scCO 2+SO2/brine system. During primary drainage CO2 displaced 52.5% of brine, i.e., Swi = 0.475. The subsequent imbibition led to 0.329 CO2 saturation. For all series of experiments, the ratio of SCO2r to initial CO2 saturation (1- S wi) was found to be much higher for low initial CO2 saturations. This means that greater fractions of injected CO2 can be permanently trapped at higher initial brine saturations. The results illustrated that very promising fractions (about 49 to 83 %) of the initial CO2 saturation can be trapped permanently. (Abstract shortened by UMI.).

  19. Characterisation and monitoring of the Excavation Disturbed Zone (EDZ) in fractured gneisses of the Roselend underground laboratory: permeability measurements, transport property changes and related radon bursts

    Science.gov (United States)

    Wassermann, Jérôme; Sabroux, Jean-Christophe; Richon, Patrick; Pontreau, Sébastien; Guillon, Sophie; Pili, Eric

    2010-05-01

    The Roselend tunnel was drilled in the fifties by blasting in the micashists, granites and gneisses of the Méraillet massif (French Alps). It is situated on the shore of the Roselend reservoir Lake near its dam. Several tectonic shear fractures related to the Alpine orogeny intersect the dead end tunnel (with length of 128 m and section about 2 m), indeed the fracture density varies from 0.45 to 1 fracture per meter along the tunnel (Dezayes and Villemin 2002). Some fractures are partially or totally filled with secondary minerals. The flow rates of percolating water through the fractured medium are seasonal dependent. Large fractures drain a large fluid volume unlike small ones that drain limited fluid volume (Patriarche et al. 2007). The Roselend underground laboratory allows the study of the geochemical and geophysical responses of a fractured rock mass to periodic sollicitations due to water level variations of the nearby Roselend reservoir Lake. The tunnel was instrumented in the nineties to understand the relationship between radon (Rn-222) concentration and water level variations of the Roselend reservoir Lake (Trique et al. 1999). In order to characterize the geometry and the extent of the EDZ, core drilling and permeability measurements through pneumatic testing are performed along the Roselend tunnel. Drilled core analysis consists of direct observations at a macroscopic scale of fractures (density of fractures from EDZ) and also at a microscopic scale via thin sections. Method of pressure build-up in wells (Jakubick and Franz 1993, Bossart et al. 2002) is used to determine permeability profile along each borehole and hence to precise the extent and geometry of the EDZ. A strong correlation is observed between permeability profiles and the density of fractures estimated from core analysis. The extent of the EDZ appears to be about one tunnel radius i.e. one meter around the tunnel corridor. Another experiment consisting of continuous differential

  20. Permeability of WIPP Salt During Damage Evolution and Healing

    International Nuclear Information System (INIS)

    BODNER, SOL R.; CHAN, KWAI S.; MUNSON, DARRELL E.

    1999-01-01

    The presence of damage in the form of microcracks can increase the permeability of salt. In this paper, an analytical formulation of the permeability of damaged rock salt is presented for both initially intact and porous conditions. The analysis shows that permeability is related to the connected (i.e., gas accessible) volumetric strain and porosity according to two different power-laws, which may be summed to give the overall behavior of a porous salt with damage. This relationship was incorporated into a constitutive model, known as the Multimechanism Deformation Coupled Fracture (MDCF) model, which has been formulated to describe the inelastic flow behavior of rock salt due to coupled creep, damage, and healing. The extended model was used to calculate the permeability of rock salt from the Waste Isolation Pilot Plant (WIPP) site under conditions where damage evolved with stress over a time period. Permeability changes resulting from both damage development under deviatoric stresses and damage healing under hydrostatic pressures were considered. The calculated results were compared against experimental data from the literature, which indicated that permeability in damaged intact WIPP salt depends on the magnitude of the gas accessible volumetric strain and not on the total volumetric strain. Consequently, the permeability of WIPP salt is significantly affected by the kinetics of crack closure, but shows little dependence on the kinetics of crack removal by sintering

  1. An Integrated Capillary, Buoyancy, and Viscous-Driven Model for Brine/CO2Relative Permeability in a Compositional and Parallel Reservoir Simulator

    KAUST Repository

    Kong, X.; Delshad, M.; Wheeler, M. F.

    2012-01-01

    The effectiveness of CO2 storage in the saline aquifers is governed by the interplay of capillary, viscous, and buoyancy forces. Recent experimental study reveals the impact of pressure, temperature, and salinity on interfacial tension (IFT) between CO2 and brine. The dependence of CO2-brine relative permeability and capillary pressure on pressure (IFT) is also clearly evident in published experimental results. Improved understanding of the mechanisms that control the migration and trapping of CO2 in subsurface is crucial to design future storage projects that warrant long-term and safe containment. Simulation studies ignoring the buoyancy and also variation in interfacial tension and the effect on the petrophysical properties such as trapped CO2 saturations, relative permeability, and capillary pressure have a poor chance of making accurate predictions of CO2 injectivity and plume migration. We have developed and implemented a general relative permeability model that combines effects of pressure gradient, buoyancy, and IFT in an equation of state (EOS) compositional and parallel simulator. The significance of IFT variations on CO2 migration and trapping is assessed.

  2. An Integrated Capillary, Buoyancy, and Viscous-Driven Model for Brine/CO2Relative Permeability in a Compositional and Parallel Reservoir Simulator

    KAUST Repository

    Kong, X.

    2012-11-03

    The effectiveness of CO2 storage in the saline aquifers is governed by the interplay of capillary, viscous, and buoyancy forces. Recent experimental study reveals the impact of pressure, temperature, and salinity on interfacial tension (IFT) between CO2 and brine. The dependence of CO2-brine relative permeability and capillary pressure on pressure (IFT) is also clearly evident in published experimental results. Improved understanding of the mechanisms that control the migration and trapping of CO2 in subsurface is crucial to design future storage projects that warrant long-term and safe containment. Simulation studies ignoring the buoyancy and also variation in interfacial tension and the effect on the petrophysical properties such as trapped CO2 saturations, relative permeability, and capillary pressure have a poor chance of making accurate predictions of CO2 injectivity and plume migration. We have developed and implemented a general relative permeability model that combines effects of pressure gradient, buoyancy, and IFT in an equation of state (EOS) compositional and parallel simulator. The significance of IFT variations on CO2 migration and trapping is assessed.

  3. Evaluation of different toxicity assays applied to proliferating cells and to stratified epithelium in relation to permeability enhancement with glycocholate

    DEFF Research Database (Denmark)

    Eirheim, Heidi Ugelstad; Bundgaard, Christoffer; Nielsen, Hanne Mørck

    2004-01-01

    The purpose of the present study was to evaluate different toxicity assays for use on proliferating buccal TR146 cells and on stratified TR146 epithelium and to compare these results to the permeability enhancing effect of glycocholate (GC). Both the proliferating cells and the epithelium were...... across the epithelium concurrent with a decrease in the transepithelial electrical resistance (TEER) was also determined. The robustness of the epithelium was significantly higher than that of the proliferating cells (P...

  4. Relating transport modeling to nanofiltration membrane fabrication: Navigating the permeability-selectivity trade-off in desalination pretreatment

    OpenAIRE

    Labban, Omar; Lienhard, John H

    2018-01-01

    Faced with a pressing need for membranes with a higher permeability and selectivity, the field of membrane technology can benefit from a systematic framework for designing membranes with the necessary physical characteristics. In this work, we present an approach through which transport modeling is employed in fabricating specialized nanofiltration membranes, that experimentally demonstrate enhanced selectivity. Specifically, the Donnan-Steric Pore Model with dielectric exclusion (DSPM-DE) is...

  5. A relative permeability model to derive fractional-flow functions of water-alternating-gas and surfactant-alternating-gas foam core-floods

    International Nuclear Information System (INIS)

    Al-Mossawy, Mohammed Idrees; Demiral, Birol; Raja, D M Anwar

    2013-01-01

    Foam is used in enhanced oil recovery to improve the sweep efficiency by controlling the gas mobility. The surfactant-alternating-gas (SAG) foam process is used as an alternative to the water-alternating-gas (WAG) injection. In the WAG technique, the high mobility and the low density of the gas lead the gas to flow in channels through the high permeability zones of the reservoir and to rise to the top of the reservoir by gravity segregation. As a result, the sweep efficiency decreases and there will be more residual oil in the reservoir. The foam can trap the gas in liquid films and reduces the gas mobility. The fractional-flow method describes the physics of immiscible displacements in porous media. Finding the water fractional flow theoretically or experimentally as a function of the water saturation represents the heart of this method. The relative permeability function is the conventional way to derive the fractional-flow function. This study presents an improved relative permeability model to derive the fractional-flow functions for WAG and SAG foam core-floods. The SAG flow regimes are characterized into weak foam, strong foam without a shock front and strong foam with a shock front. (paper)

  6. Personality, relationship conflict, and teamwork-related mental models

    NARCIS (Netherlands)

    Vîrgă, D.; Curseu, P.L.; Maricuţoiu, L.; Sava, S.A.; Macsinga, I.; Măgurean, S.

    2014-01-01

    This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested

  7. Electrokinetic effects and fluid permeability

    International Nuclear Information System (INIS)

    Berryman, J.G.

    2003-01-01

    Fluid permeability of porous media depends mainly on connectivity of the pore space and two physical parameters: porosity and a pertinent length-scale parameter. Electrical imaging methods typically establish connectivity and directly measure electrical conductivity, which can then often be related to porosity by Archie's law. When electrical phase measurements are made in addition to the amplitude measurements, information about the pertinent length scale can then be obtained. Since fluid permeability controls the ability to flush unwanted fluid contaminants from the subsurface, inexpensive maps of permeability could improve planning strategies for remediation efforts. Detailed knowledge of fluid permeability is also important for oil field exploitation, where knowledge of permeability distribution in three dimensions is a common requirement for petroleum reservoir simulation and analysis, as well as for estimates on the economics of recovery

  8. Evaluating Molecular Properties Involved in Transport of Small Molecules in Stratum Corneum: A Quantitative Structure-Activity Relationship for Skin Permeability

    Directory of Open Access Journals (Sweden)

    Chen-Peng Chen

    2018-04-01

    Full Text Available The skin permeability (Kp defines the rate of a chemical penetrating across the stratum corneum. This value is widely used to quantitatively describe the transport of molecules in the outermost layer of epidermal skin and indicate the significance of skin absorption. This study defined a Kp quantitative structure-activity relationship (QSAR based on 106 chemical substances of Kp measured using human skin and interpreted the molecular interactions underlying transport behavior of small molecules in the stratum corneum. The Kp QSAR developed in this study identified four molecular descriptors that described the molecular cyclicity in the molecule reflecting local geometrical environments, topological distances between pairs of oxygen and chlorine atoms, lipophilicity, and similarity to antineoplastics in molecular properties. This Kp QSAR considered the octanol-water partition coefficient to be a direct influence on transdermal movement of molecules. Moreover, the Kp QSAR identified a sub-domain of molecular properties initially defined to describe the antineoplastic resemblance of a compound as a significant factor in affecting transdermal permeation of solutes. This finding suggests that the influence of molecular size on the chemical’s skin-permeating capability should be interpreted with other relevant physicochemical properties rather than being represented by molecular weight alone.

  9. Evaluating Molecular Properties Involved in Transport of Small Molecules in Stratum Corneum: A Quantitative Structure-Activity Relationship for Skin Permeability.

    Science.gov (United States)

    Chen, Chen-Peng; Chen, Chan-Cheng; Huang, Chia-Wen; Chang, Yen-Ching

    2018-04-15

    The skin permeability ( Kp ) defines the rate of a chemical penetrating across the stratum corneum. This value is widely used to quantitatively describe the transport of molecules in the outermost layer of epidermal skin and indicate the significance of skin absorption. This study defined a Kp quantitative structure-activity relationship (QSAR) based on 106 chemical substances of Kp measured using human skin and interpreted the molecular interactions underlying transport behavior of small molecules in the stratum corneum. The Kp QSAR developed in this study identified four molecular descriptors that described the molecular cyclicity in the molecule reflecting local geometrical environments, topological distances between pairs of oxygen and chlorine atoms, lipophilicity, and similarity to antineoplastics in molecular properties. This Kp QSAR considered the octanol-water partition coefficient to be a direct influence on transdermal movement of molecules. Moreover, the Kp QSAR identified a sub-domain of molecular properties initially defined to describe the antineoplastic resemblance of a compound as a significant factor in affecting transdermal permeation of solutes. This finding suggests that the influence of molecular size on the chemical's skin-permeating capability should be interpreted with other relevant physicochemical properties rather than being represented by molecular weight alone.

  10. Relation between histamine release and dye permeability of pulmonary blood-air barrier in x-irradiated rat

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, H [Kobe Univ. (Japan). School of Medicine

    1976-04-01

    The histamine-release kinetics and the influence of released histamine on the permeability of the pulmonary blood-air(BA) barrier during the early period after either whole-body or thoracic x irradiation of the rat were studied. Histamine contents of skin and lung of the irradiated rat decreased rapidly, reaching a minimum at 5 h, and this histamine depletion continued for at least 7 days. Conversely, in circulating blood histamine increased during the early period of 5 h and then decreased gradually. This early increase was linear up to 500R and then became saturated between 500 and 1,000R. Administration of polymixine B (5mg/100g body weight) to rats liberated histamine similarly. Rat sera containg histamine released soon after irradiation enhanced the capillary permeability of Evans blue(EB) in the guinea pig skin reaction, which was effectively countered by pretreatment of the guinea pig with anti-histaminic pyribenzamine (29..mu..g/100g body weight), but not by anti-serotonic chlorpromazine (0.3mg/100g body weight). Similarly, perhaps only the EB-bound serum albumin (EB-albumin), that was seen in alveolar perfusate, penetrated more through the pulmonary BA-barrier with increasing x-ray dose, in parallel with the increase in blood histamine. Pyribenzamine inhibited this effect effectively, but cysteamine (a radical scavenger) did so only partially. Thus, it seems possible that at soon after x irradiation the enhanced permeability of EB-albumin through the BA barrier of rat lung is due preferentially to the pharmacologic action of released histamine and subsidiarily to radiation damage to pulmonary cells.

  11. Gut Microbiota Richness and Composition and Dietary Intake of Overweight Pregnant Women Are Related to Serum Zonulin Concentration, a Marker for Intestinal Permeability.

    Science.gov (United States)

    Mokkala, Kati; Röytiö, Henna; Munukka, Eveliina; Pietilä, Sami; Ekblad, Ulla; Rönnemaa, Tapani; Eerola, Erkki; Laiho, Asta; Laitinen, Kirsi

    2016-09-01

    Increased intestinal permeability may precede adverse metabolic conditions. The extent to which the composition of the gut microbiota and diet contribute to intestinal permeability during pregnancy is unknown. The aim was to investigate whether the gut microbiota and diet differ according to serum zonulin concentration, a marker of intestinal permeability, in overweight pregnant women. This cross-sectional study included 100 overweight women [mean age: 29 y; median body mass index (in kg/m(2)): 30] in early pregnancy (zonulin (primary outcome) was determined by using ELISA, gut microbiota by 16S ribosomal RNA sequencing, and dietary intake of macro- and micronutrients from 3-d food diaries. The Mann-Whitney U test was used for pairwise comparisons and linear regression and Spearman's nonparametric correlations for relations between serum zonulin and other outcome variables. Women were divided into "low" (zonulin groups on the basis of the median concentration of zonulin (46.4 ng/mL). The richness of the gut microbiota (Chao 1, observed species and phylogenetic diversity) was higher in the low zonulin group than in the high zonulin group (P = 0.01). The abundances of Bacteroidaceae and Veillonellaceae, Bacteroides and Blautia, and Blautia sp. were lower and of Faecalibacterium and Faecalibacterium prausnitzii higher (P zonulin group than in the high zonulin group. Dietary quantitative intakes of n-3 (ω-3) polyunsaturated fatty acids (PUFAs), fiber, and a range of vitamins and minerals were higher (P zonulin group than those in the high zonulin group. The richness and composition of the gut microbiota and the intake of n-3 PUFAs, fiber, and a range of vitamins and minerals in overweight pregnant women are associated with serum zonulin concentration. Modification of the gut microbiota and diet may beneficially affect intestinal permeability, leading to improved metabolic health of both the mother and fetus. This trial was registered at clinicaltrials.gov as NCT

  12. Effect of Viscous Instability on Unsteady-State Relative Permeability Effet de l'instabilité visqueuse sur la perméabilité relative en régime irrégulier

    Directory of Open Access Journals (Sweden)

    Sarma H. K.

    2006-11-01

    Full Text Available This paper presents the results of an experimental investigation into the relationship between the extent of viscous instability involved in a laboratory displacement and the relative permeability inferred from measured displacement data. Oil displacement experiments were conducted in a triaxially confined silica sand pack. The extent of viscous instability was varied by using mineral oils of different viscosities and by conducting the displacement runs at different flow rates. Relative permeabilities were calculated using both a history matching technique developed by R. M. Sigmund and F. G. McCaffery (8 and an explicit technique suggested by H. K. Sarma and R. G. Bentsen (14. Although, in principle, this explicit technique is similar to the JBN method (11, it is simpler to use in that, it does not require graphical or numerical differentiation of the experimental data. The technique uses two monotonic functional equations, which satisfy all physical conditions that can be imposed on the system, to smooth cumulative oil production and pressure drop histories. Furthermore, these functional equations can also be utilized to predict end-point displacement parameters, such as : Sor and kwor, for displacement experiments which are terminated before reaching the actual end-point. The results show that the two techniques for calculating relative permeabilities from unsteady-state displacement data provide essentially similar results, and that viscous instability significantly affects the relative permeability measurements. The breakthrough recovery, residual oil saturation and the end-point water permeability were all affected by the extent of viscous instability present during the displacement. It was found that these parameters show a systematic dependence on the extent of viscous instability as characterized by the instability number (Isr of E. J. Peters and D. L. Flock (19. Also, the results suggest that the relative permeability curves approach a

  13. The Relational Humor Inventory: Functions of Humor in Close Relationships.

    Science.gov (United States)

    DeKoning, E.; Weiss, R. L.

    2002-01-01

    This study describes the development of a self-report measure of functional humor in relationships. People were asked to report on their own and their partner's use of humor in the marriage. The Relational Humor Inventory proved to be a useful instrument for tapping important positive and negative relationship behaviors. (Contains 30 references, 4…

  14. Polymeric membrane materials: new aspects of empirical approaches to prediction of gas permeability parameters in relation to permanent gases, linear lower hydrocarbons and some toxic gases.

    Science.gov (United States)

    Malykh, O V; Golub, A Yu; Teplyakov, V V

    2011-05-11

    Membrane gas separation technologies (air separation, hydrogen recovery from dehydrogenation processes, etc.) use traditionally the glassy polymer membranes with dominating permeability of "small" gas molecules. For this purposes the membranes based on the low free volume glassy polymers (e.g., polysulfone, tetrabromopolycarbonate and polyimides) are used. On the other hand, an application of membrane methods for VOCs and some toxic gas recovery from air, separation of the lower hydrocarbons containing mixtures (in petrochemistry and oil refining) needs the membranes with preferable penetration of components with relatively larger molecular sizes. In general, this kind of permeability is characterized for rubbers and for the high free volume glassy polymers. Data files accumulated (more than 1500 polymeric materials) represent the region of parameters "inside" of these "boundaries." Two main approaches to the prediction of gas permeability of polymers are considered in this paper: (1) the statistical treatment of published transport parameters of polymers and (2) the prediction using model of ≪diffusion jump≫ with consideration of the key properties of the diffusing molecule and polymeric matrix. In the frames of (1) the paper presents N-dimensional methods of the gas permeability estimation of polymers using the correlations "selectivity/permeability." It is found that the optimal accuracy of prediction is provided at n=4. In the frames of the solution-diffusion mechanism (2) the key properties include the effective molecular cross-section of penetrating species to be responsible for molecular transportation in polymeric matrix and the well known force constant (ε/k)(eff i) of {6-12} potential for gas-gas interaction. Set of corrected effective molecular cross-section of penetrant including noble gases (He, Ne, Ar, Kr, Xe), permanent gases (H(2), O(2), N(2), CO), ballast and toxic gases (CO(2), NO(,) NO(2), SO(2), H(2)S) and linear lower hydrocarbons (CH(4

  15. Numerical Aspects Related to the Dynamic Update of Anisotropic Permeability Field During the Transport of Nanoparticles in the Subsurface

    KAUST Repository

    Chen, Meng-Huo; Salama, Amgad; Ei-Amin, Mohamed

    2016-01-01

    Nanoparticles are particles that are between 1 and 100 nanometers in size. They present possible dangers to the environment due to the high surface to volume ratio, which can make the particles very reactive or catalytic. Furthermore, rapid increase in the implementation of nanotechnologies has released large amount of the nanowaste into the environment. In the last two decades, transport of nanoparticles in the subsurface and the potential hazard they impose to the environment have attracted the attention of researchers. In this work, we use numerical simulation to investigate the problem regarding the transport phenomena of nanoparticles in anisotropic porous media. We consider the case in which the permeability in the principal direction components will vary with respect to time. The interesting thing in this case is the fact that the anisotropy could disappear with time. We investigate the effect of the degenerating anisotropy on various fields such as pressure, porosity, concentration and velocities.

  16. Numerical Aspects Related to the Dynamic Update of Anisotropic Permeability Field During the Transport of Nanoparticles in the Subsurface

    KAUST Repository

    Chen, Meng-Huo

    2016-06-01

    Nanoparticles are particles that are between 1 and 100 nanometers in size. They present possible dangers to the environment due to the high surface to volume ratio, which can make the particles very reactive or catalytic. Furthermore, rapid increase in the implementation of nanotechnologies has released large amount of the nanowaste into the environment. In the last two decades, transport of nanoparticles in the subsurface and the potential hazard they impose to the environment have attracted the attention of researchers. In this work, we use numerical simulation to investigate the problem regarding the transport phenomena of nanoparticles in anisotropic porous media. We consider the case in which the permeability in the principal direction components will vary with respect to time. The interesting thing in this case is the fact that the anisotropy could disappear with time. We investigate the effect of the degenerating anisotropy on various fields such as pressure, porosity, concentration and velocities.

  17. Experimental study on the response characteristics of coal permeability to pore pressure under loading and unloading conditions

    Science.gov (United States)

    Ye, Zhiwei; Zhang, Lei; Hao, Dingyi; Zhang, Cun; Wang, Chen

    2017-10-01

    In order to study the response characteristics of coal permeability to pore pressure, seepage experiments under different simulated in situ stresses on loading and unloading paths are carried out using the self-developed Gas Flow and Displacement Testing Apparatus (GFDTA) system. Based on the analysis of the experimental data, the relationship between average pore pressure and permeability is found to basically obey the function distribution of a two degree polynomial. In this paper, two aspects of the relationship between permeability and pore pressure are explained: the Klinbenberg effect and expansion, and the penetration of the initial fracture. Under low pore pressure, the decrease in the Klinbenberg effect is the main reason for the decrease in permeability with increased pore pressure. Under relatively high pore pressure, the increase in pore pressure leads to the initial fracture expansion and penetration of the coal sample, which causes an increase in permeability. In order to evaluate the sensitivity of the permeability response to pore pressure changes, the permeability dispersion and pore pressure sensitivity coefficients are defined. After the sensitivity analysis, it was concluded that the loading history changed the fracture structure of the original coal sample and reduced its permeability sensitivity to pore pressure. Under low pore pressure, the Klinbenberg effect is the reason for the decrease in pore pressure sensitivity. Lastly, the permeability-pore pressure relationship is divided into three stages to describe the different response characteristics individually.

  18. THE CHANGING DIMENSIONS OF PUBLIC RELATIONS: THE RELATIONSHIP BETWEEN BRAND MANAGEMENT AND PUBLIC RELATIONS

    OpenAIRE

    KÖKER, E. PELİN BAYTEKİN MİNE YENİÇERİ ALEMDAR

    2008-01-01

    The changes in the dimensions of public relations, due to the globalization effect on the business enterprises, are remarkable. In this manner, the relationship of public relations with re-engineering, total quality management, six sigma approach, event management, crisis management, reputation management, knowledge management and customer relationship management is evaluated in this study. Moreover, after establishing these interactions, the relationship between public relations and brand ma...

  19. Developments in permeable and low permeability barriers

    International Nuclear Information System (INIS)

    Jefferis, S.A.; Norris, G.H.; Thomas, A.O.

    1997-01-01

    The concept of the reactive treatment zone whereby pollutants are attenuated as they move along a pathway in the ground has enabled a re-thinking of many of the concepts of containment. In particular it offers the potential for the control of the flux from a contaminated area by controlling the contaminant concentration in the pathway(s) as well as or instead of using a low permeability barrier. The paper outlines the basic concepts of the reactive treatment zone and the use of permeable and low permeability reactive systems. The paper then gives a case history of the installation of a permeable barrier using an in-situ reaction chamber

  20. Relationship between relative humidity and the dew point ...

    African Journals Online (AJOL)

    This research was aimed at determining the relationship between relative humidity and the dew point temperature in Benin City, Edo State, Nigeria. The dew point temperature was approximated from the measured air temperature and relative humidity with the aid of a currently self-designed weather monitoring system.

  1. Relations among Positive Parenting, parent-child Relationship, and Empathy

    DEFF Research Database (Denmark)

    Wu, Liyun; Zhang, Xingli; Shi, Jiannong

    This study demonstrated relations among 2 features of positive parenting——supportive responsiveness to distress and warmth ,parent-child relationship and empathy.171 children aged 8-10 years (mean age = 9.31 years, 89 girls) participated in the study.In school,participants completed Empathic......,Prosocial Response to Another’s Distress Scale,Parental Acceptance-Rejection Questionnaire, Coping with Children’s Negative Emotions Questionaire,Network of Relationships Inventory. Results showed that: (1)Parents' supportive responsiveness to distress, but not warmth, predicted children's empathy.(2)Near parent-child...... parent-child relationship....

  2. Estimating the Permeability of Carbonate Rocks from the Fractal Properties of Moldic Pores using the Kozeny-Carman Equation

    Directory of Open Access Journals (Sweden)

    Adewale Amosu

    2018-02-01

    Full Text Available Reservoir modeling of carbonate rocks requires a proper understanding of the pore space distribution and its relationship to permeability. Using a pigeonhole fractal model we characterize the fractal geometry of moldic pore spaces and extract the fractal dimension. We apply the Kozeny-Carman equation and equations relating the tortuosity and the porosity to the fractal dimension to derive an empirical relationship between permeability and porosity.

  3. Personality, Relationship Conflict, and Teamwork-Related Mental Models

    Science.gov (United States)

    Vîrgă, Delia; CurŞeu, Petru Lucian; Maricuţoiu, Laurenţiu; Sava, Florin A.; Macsinga, Irina; Măgurean, Silvia

    2014-01-01

    This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models. PMID:25372143

  4. Personality, relationship conflict, and teamwork-related mental models.

    Directory of Open Access Journals (Sweden)

    Delia Vîrgă

    Full Text Available This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members' evaluative cognitions related to teamwork quality (teamwork-related mental models. Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models.

  5. Personality, relationship conflict, and teamwork-related mental models.

    Science.gov (United States)

    Vîrgă, Delia; Curşeu, Petru Lucian; CurŞeu, Petru Lucian; Maricuţoiu, Laurenţiu; Sava, Florin A; Macsinga, Irina; Măgurean, Silvia

    2014-01-01

    This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models.

  6. [Jealousy in close relationships: personal, relational and situational variables].

    Science.gov (United States)

    Demirtaş, H Andaç; Dönmez, Ali

    2006-01-01

    In this study, the effects of personal, situational, and relational variables (such as age, gender, gender role orientation, duration of relationship, relational satisfaction, and physical attractiveness of the partner) on jealousy are investigated. A sample of 454 individuals currently involved in dating or marital relationships (48 % married, 52 % unmarried) completed the Romantic Jealousy Questionnaire, Bem Sex Role Inventory, and Rosenberg Self-Esteem Scale. Stepwise regression analyses and 2 (gender) x2 (gender role orientation) x2 (relational type) ANOVA's were submitted for analyzing the data. Analysis indicated that unmarried people reported higher levels of jealousy than married people (F1-446 = 5.029). Married women reported less jealousy than unmarried women and married women reported more jealousy than married men. Age, relational satisfaction level, expectation level about the duration of the relationship, and physical attractiveness of the partner were unique predictors of the reported level of jealousy (R2 = 0.12; adjusted R2 = 0.11; P physical, emotional, and cognitive responses to jealousy compared to men. Women used more constructive (F1-446 = 6.27) and less destructive strategies than men (F1-446 = 6.27). Unmarried people used more destructive strategies than married people (F1-446 = 3.84). Age, self-esteem, and the duration of the relationship were unique predictors of coping strategies. The present study revealed that jealousy was a multidimensional variable. In particular, relational type, self-esteem, age, relational satisfaction, and sex are highly correlated with jealousy.

  7. Understanding heat and groundwater flow through continental flood basalt provinces: insights gained from alternative models of permeability/depth relationships for the Columbia Plateau, USA

    Science.gov (United States)

    Burns, Erick R.; Williams, Colin F.; Ingebritsen, Steven E.; Voss, Clifford I.; Spane, Frank A.; DeAngelo, Jacob

    2015-01-01

    Heat-flow mapping of the western USA has identified an apparent low-heat-flow anomaly coincident with the Columbia Plateau Regional Aquifer System, a thick sequence of basalt aquifers within the Columbia River Basalt Group (CRBG). A heat and mass transport model (SUTRA) was used to evaluate the potential impact of groundwater flow on heat flow along two different regional groundwater flow paths. Limited in situ permeability (k) data from the CRBG are compatible with a steep permeability decrease (approximately 3.5 orders of magnitude) at 600–900 m depth and approximately 40°C. Numerical simulations incorporating this permeability decrease demonstrate that regional groundwater flow can explain lower-than-expected heat flow in these highly anisotropic (kx/kz ~ 104) continental flood basalts. Simulation results indicate that the abrupt reduction in permeability at approximately 600 m depth results in an equivalently abrupt transition from a shallow region where heat flow is affected by groundwater flow to a deeper region of conduction-dominated heat flow. Most existing heat-flow measurements within the CRBG are from shallower than 600 m depth or near regional groundwater discharge zones, so that heat-flow maps generated using these data are likely influenced by groundwater flow. Substantial k decreases at similar temperatures have also been observed in the volcanic rocks of the adjacent Cascade Range volcanic arc and at Kilauea Volcano, Hawaii, where they result from low-temperature hydrothermal alteration.

  8. Testing relationships between values and food-related lifestyle:

    DEFF Research Database (Denmark)

    Brunsø, Karen; Scholderer, Joachim; Grunert, Klaus G.

    2004-01-01

    The value survey developed by Shalom Schwartz (1992) has been applied in many countries with different purposes. In this study we present a new way of analysing the theoretically assumed circumplex structure of Schwartz value survey and its relationships to other constructs, here the instrument...... food-related lifestyle. In two countries; Germany and Spain, data were collected. In each country 1000 interviews were carried out where consumers were asked about their value priorities and about their food-related lifestyle. The study provides new insights into the way values influence peoples' food......-related lifestyle in Germany and Spain, and the results validate both the Schwartz value survey and the food-related lifestyle instrument in a nomological sense, since significant and meaningful relationships were found between the two constructs....

  9. The Effect of Relational Constructs on Relationship Performance

    NARCIS (Netherlands)

    P.C. Verhoef (Peter); Ph.H.B.F. Franses (Philip Hans); J.C. Hoekstra (Janny)

    2000-01-01

    textabstractWe examine the effect of relational constructs, such as satisfaction, trust and commitment on relationship performance (that is, positive word-of-mouth communication and the margin provided by each customer) of customers of an insurance company. A central issue concerns the effect of

  10. A lattice Boltzmann investigation of steady-state fluid distribution, capillary pressure and relative permeability of a porous medium: Effects of fluid and geometrical properties

    Science.gov (United States)

    Li, Zi; Galindo-Torres, Sergio; Yan, Guanxi; Scheuermann, Alexander; Li, Ling

    2018-06-01

    Simulations of simultaneous steady-state two-phase flow in the capillary force-dominated regime were conducted using the state-of-the-art Shan-Chen multi-component lattice Boltzmann model (SCMC-LBM) based on two-dimensional porous media. We focused on analyzing the fluid distribution (i.e., WP fluid-solid, NP fluid-solid and fluid-fluid interfacial areas) as well as the capillary pressure versus saturation curve which was affected by fluid and geometrical properties (i.e., wettability, adhesive strength, pore size distribution and specific surface area). How these properties influenced the relative permeability versus saturation relation through apparent effective permeability and threshold pressure gradient was also explored. The SCMC-LBM simulations showed that, a thin WP fluid film formed around the solid surface due to the adhesive fluid-solid interaction, resulting in discrete WP fluid distributions and reduction of the WP fluid mobility. Also, the adhesive interaction provided another source of capillary pressure in addition to capillary force, which, however, did not affect the mobility of the NP fluid. The film fluid effect could be enhanced by large adhesive strength and fine pores in heterogeneous porous media. In the steady-state infiltration, not only the NP fluid but also the WP fluid were subjected to the capillary resistance. The capillary pressure effect could be alleviated by decreased wettability, large average pore radius and improved fluid connectivity in heterogeneous porous media. The present work based on the SCMC-LBM investigations elucidated the role of film fluid as well as capillary pressure in the two-phase flow system. The findings have implications for ways to improve the macroscopic flow equation based on balance of force for the steady-state infiltration.

  11. Film Permeability Determination Using Static Permeability Cells

    Science.gov (United States)

    The permeability of tarps to soil fumigant pesticides varies depending on the active ingredient chemical: dimethyl disulfide (DMDS), methyl bromide, chloropicrin, or other. The diffusion rate can be represented by the mass transfer coefficient (MTC).

  12. Clogging in permeable concrete: A review.

    Science.gov (United States)

    Kia, Alalea; Wong, Hong S; Cheeseman, Christopher R

    2017-05-15

    Permeable concrete (or "pervious concrete" in North America) is used to reduce local flooding in urban areas and is an important sustainable urban drainage system. However, permeable concrete exhibits reduction in permeability due to clogging by particulates, which severely limits service life. This paper reviews the clogging mechanism and current mitigating strategies in order to inform future research needs. The pore structure of permeable concrete and characteristics of flowing particulates influence clogging, which occurs when particles build-up and block connected porosity. Permeable concrete requires regular maintenance by vacuum sweeping and pressure washing, but the effectiveness and viability of these methods is questionable. The potential for clogging is related to the tortuosity of the connected porosity, with greater tortuosity resulting in increased potential for clogging. Research is required to develop permeable concrete that can be poured on-site, which produces a pore structure with significantly reduced tortuosity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Permeability Estimation of Rock Reservoir Based on PCA and Elman Neural Networks

    Science.gov (United States)

    Shi, Ying; Jian, Shaoyong

    2018-03-01

    an intelligent method which based on fuzzy neural networks with PCA algorithm, is proposed to estimate the permeability of rock reservoir. First, the dimensionality reduction process is utilized for these parameters by principal component analysis method. Further, the mapping relationship between rock slice characteristic parameters and permeability had been found through fuzzy neural networks. The estimation validity and reliability for this method were tested with practical data from Yan’an region in Ordos Basin. The result showed that the average relative errors of permeability estimation for this method is 6.25%, and this method had the better convergence speed and more accuracy than other. Therefore, by using the cheap rock slice related information, the permeability of rock reservoir can be estimated efficiently and accurately, and it is of high reliability, practicability and application prospect.

  14. Exchange Rate – Relative Price Nonlinear Cointegration Relationship in Malaysia

    OpenAIRE

    Venus Khim-Sen Liew; Chee-Keong Choong; Evan Lau; Kian-Ping Lim

    2005-01-01

    The finding of exchange rate–relative price nonlinear cointegration relationship in Malaysia, among others, suggests that nonlinear Purchasing Power Parity (PPP) equilibrium may be regarded as reference point in judging the short run misalignment of the Ringgit currency and thereby deducing effective policy actions. Moreover, economists who wish to extend the simple PPP exchange rate model into the more complicated monetary exchange models may do so comfortably, at least in the text of Malays...

  15. Suitability of Torrent Permeability Tester to measure air-permeability of covercrete

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, C.; Gonzales-Gasca, C. [Institute of Construction Sciences ' Eduardo Torroja' , Madrid (Spain); Torrent, R. [Portland Cement Institute, (Argentina)

    2000-07-01

    Suitability of the Torrent Permeability Tester (TPT) to measure the permeability of covercrete to air, both in the laboratory and the field, is investigated, and test results obtained in laboratory studies are discussed. The tests performed included the determination of air permeability (TPT method), oxygen permeability (Cembureau method) and capillary suction, rapid chloride permeability test (ASTM C 1202), as well as a one-year carbonation depth test. Concrete specimens of various compositions and curing regimes were used in the tests; the gas-permeability tests were repeated on the same specimens after 28 days, than again at 6 months and 12 months. Test results confirmed the suitability of the TPT as a useful tool in the characterization of the quality the of concrete cover. It was found to be sensitive to changes in concrete quality; repeatable for sensitive properties such as gas permeability ; also, it was found to correlate well with other durability-related properties. 10 refs., 8 tabs., 8 figs.

  16. Causal Relationship Between Relative Price Variability and Inflation in Turkey:

    Directory of Open Access Journals (Sweden)

    Nebiye Yamak

    2016-09-01

    Full Text Available This study investigates the causal relationship between inflation and relative price variability in Turkey for the period of January 2003-January 2014, by using panel data. In the study, a Granger (1969 non-causality test in heterogeneous panel data models developed by Dumitrescu and Hurlin (2012 is utilized to determine the causal relations between inflation rate relative price variability. The panel data consists of 4123 observations: 133 time observations and 31 cross-section observations. The results of panel causality test indicate that there is a bidirectional causality between inflation rate and relative price variability by not supporting the imperfection information model of Lucas and the menu cost model of Ball and Mankiw.

  17. Permeability prediction in chalks

    DEFF Research Database (Denmark)

    Alam, Mohammad Monzurul; Fabricius, Ida Lykke; Prasad, Manika

    2011-01-01

    The velocity of elastic waves is the primary datum available for acquiring information about subsurface characteristics such as lithology and porosity. Cheap and quick (spatial coverage, ease of measurement) information of permeability can be achieved, if sonic velocity is used for permeability p...... significantly using the effective specific surface as the fluid-flow concept. The FZI unit is appropriate for highly permeable sedimentary rocks such as sandstones and limestones that have small surface areas....

  18. Relationship jealousy and its relation to emotional attachment and sexuality

    Directory of Open Access Journals (Sweden)

    Sanja Temnik

    2007-01-01

    Full Text Available The research objective was to study the emotion of relationship jealousy in context of emotional attachment and sexuality. Two main theories that try to explain the nature of this complex emotional state are the evolutionary paradigm and the so-called "double-shot" hypothesis. According to evolutionary psychologists, jealousy is an evolved adaptation, activated by threats to a valuable relationship, functioning to protect it from partial or total loss. The "double-shot" hypothesis on the other hand emphasises the importance of different beliefs men and women hold about emotional vs. sexual infidelity. Slovenian data suggests that (a emotional infidelity is the primary jealousy trigger in both sexes; (b jealousy is influenced by the socio-cultural context (the degree of sexual permissiveness and sex role egalitarity seem to be of special importance, but not by characteristics of the individuals` early life situation; (c marital status influences the tendency towards sexual or emotional jealousy in romantic relationships; (d this tendency also depends on whether the individual comes from a rural or urban environment. Because the results seem to be affected by the linguistic formulation of jealousy and each infidelity type, special attention should be directed towards a precise conceptualisation of these terms. Beliefs about the typical relationship between the emotional and sexual aspect of human relations as well as participants` self-reports indicate that men find it a lot easier to separate both types of attachment than women. In Slovenia, the degree of sexual permissiveness as well as the degree of sex role egalitarity seem to be relatively high and comparable to certain other European countries. The results support the so-called "double-shot" hypothesis, but not the evolutionary theory of jealousy as a sex-specific innate module.

  19. Permeability Tests on Eastern Scheldt Sand

    DEFF Research Database (Denmark)

    Jakobsen, Kim Parsberg

    on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Eastern Scheldt Sand. The permeability is determined by use of a falling head apparatus. Finally the test results are briefly summarised and a relationship between......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

  20. Effect of sucralfate on gastric permeability in an ex vivo model of stress-related mucosal disease in dogs.

    Science.gov (United States)

    Hill, Tracy L; Lascelles, B Duncan X; Blikslager, Anthony T

    2018-03-01

    Sucralfate is a gastroprotectant with no known systemic effects. The efficacy of sucralfate for prevention and treatment of stress-related mucosal diseases (SRMD) in dogs is unknown. To develop a canine ex vivo model of SRMD and to determine the effect of sucralfate on mucosal barrier function in this model. Gastric antral mucosa was collected immediately postmortem from 29 random-source apparently healthy dogs euthanized at a local animal control facility. Randomized experimental trial. Sucralfate (100 mg/mL) was applied to ex vivo canine gastric mucosa concurrent with and after acid injury. Barrier function was assessed by measurement of transepithelial electrical resistance (TER) and radiolabeled mannitol flux. Application of acidified Ringers solution to the mucosal side of gastric antrum caused a reduction in gastric barrier function, and washout of acidified Ringers solution allowed recovery of barrier function (TER: 34.0 ± 2.8% of control at maximum injury, 71.3 ± 5.5% at recovery, P < .001). Sucralfate application at the time of injury or after injury significantly hastened recovery of barrier function (TER: 118.0 ± 15.2% of control at maximum injury, P < .001 and 111.0 ± 15.5% at recovery, P = .35). Sucralfate appeared effective at restoring defects in gastric barrier function induced by acid and accelerating repair of tissues subjected to acid in this model, suggesting that sucralfate could have utility for the treatment and prevention of SRMD in dogs. Copyright © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  1. Decision trees to characterise the roles of permeability and solubility on the prediction of oral absorption.

    Science.gov (United States)

    Newby, Danielle; Freitas, Alex A; Ghafourian, Taravat

    2015-01-27

    Oral absorption of compounds depends on many physiological, physiochemical and formulation factors. Two important properties that govern oral absorption are in vitro permeability and solubility, which are commonly used as indicators of human intestinal absorption. Despite this, the nature and exact characteristics of the relationship between these parameters are not well understood. In this study a large dataset of human intestinal absorption was collated along with in vitro permeability, aqueous solubility, melting point, and maximum dose for the same compounds. The dataset allowed a permeability threshold to be established objectively to predict high or low intestinal absorption. Using this permeability threshold, classification decision trees incorporating a solubility-related parameter such as experimental or predicted solubility, or the melting point based absorption potential (MPbAP), along with structural molecular descriptors were developed and validated to predict oral absorption class. The decision trees were able to determine the individual roles of permeability and solubility in oral absorption process. Poorly permeable compounds with high solubility show low intestinal absorption, whereas poorly water soluble compounds with high or low permeability may have high intestinal absorption provided that they have certain molecular characteristics such as a small polar surface or specific topology. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  2. Social relationships and health related behaviors among older US adults.

    Science.gov (United States)

    Watt, Richard G; Heilmann, Anja; Sabbah, Wael; Newton, Tim; Chandola, Tarani; Aida, Jun; Sheiham, Aubrey; Marmot, Michael; Kawachi, Ichiro; Tsakos, Georgios

    2014-05-30

    Health behaviors are a key determinant of health and well-being that are influenced by the nature of the social environment. This study examined associations between social relationships and health-related behaviors among a nationally representative sample of older people. We analyzed data from three waves (1999-2004) of the US National Health and Nutrition Examination Survey (NHANES). Participants were 4,014 older Americans aged 60 and over. Log-binomial regression models estimated prevalence ratios (PR) for the associations between social relationships and each of the following health behaviors: alcohol use, smoking, physical activity and dental attendance. Health-compromising behaviors (smoking, heavy drinking and less frequent dental visits) were related to marital status, while physical activity, a health-promoting behavior, was associated with the size of friendship networks. Smoking was more common among divorced/separated (PR = 2.1; 95% CI: 1.6, 2.7) and widowed (PR = 1.7; 95% CI: 1.3, 2.3) respondents than among those married or cohabiting, after adjusting for socio-demographic background. Heavy drinking was 2.6 times more common among divorced/separated and 1.7 times more common among widowed men compared to married/cohabiting men, while there was no such association among women. For women, heavy drinking was associated with being single (PR = 1.7; 95% CI: 1.0, 2.9). Being widowed was related to a lower prevalence of having visited a dentist compared to being married or living with a partner (PR = 0.92; 95% CI 0.86, 0.99). Those with a larger circle of friends were more likely to be physically active (PR = 1.17; 95% CI:1.06, 1.28 for 5-8 versus less than 5 friends). Social relationships of older Americans were independently associated with different health-related behaviors, even after adjusting for demographic and socioeconomic determinants. Availability of emotional support did not however mediate these associations. More research is

  3. Relationship between permeability and damage in concretes at high temperature; Lien entre la permeabilite et l'endommagement dans les betons a haute temperature

    Energy Technology Data Exchange (ETDEWEB)

    Dal Pont, St

    2004-09-15

    Due to its technical and economical advantages, concrete is nowadays the most used building material in civil engineering. Even if its use is known since nearly two centuries, its behavior has not been yet completely explained due to the complexity of its porous microstructure. This fact is quite evident under particular conditions such as, by instance, during an elevation of temperature. This condition can mainly occur in two cases: due to a casualty (e.g. a fire) or in normal use conditions (e.g. storage of nuclear rejects). This work aims at contributing to the study of the phenomena that can be observed in concrete exposed to high temperatures and, in particular, focuses on the study of the evolution of intrinsic permeability. The characterisation of permeability (which is hardly measurable in hot conditions) is necessary for describing and modelling transport phenomena which occur in porous media. An experimental study has been made in collaboration with the CEA. A real-scale hollow cylinder has been instrumented with gauges for studying the evolution of temperature and gas pressure fields inside concrete. Later, the cylinder has been then numerically modelled by means of a thermo-hydro-chemical (THC) and a thermo-hydro-chemo-mechanical (THCM) model. The THC model, implemented by means of the finite volume method, has allowed a first, qualitative study of the behaviour of concrete submitted to high temperature. This model, which, for sake of simplicity, has neglected all mechanical effects, has allowed the description of the main phenomena occurring inside concrete: mass transport, phase changes, microstructure evolution. Later, the modelling has been completed by means of the THCM model using the Hitecosp code, implemented by means of the finite element method at the university of Padua. This code allows a very complete description of the phenomena occurring inside concrete and takes into consideration the mechanical behavior of concrete by means of an

  4. Relationship between permeability and damage in concretes at high temperature; Lien entre la permeabilite et l'endommagement dans les betons a haute temperature

    Energy Technology Data Exchange (ETDEWEB)

    Dal Pont, St

    2004-09-15

    Due to its technical and economical advantages, concrete is nowadays the most used building material in civil engineering. Even if its use is known since nearly two centuries, its behavior has not been yet completely explained due to the complexity of its porous microstructure. This fact is quite evident under particular conditions such as, by instance, during an elevation of temperature. This condition can mainly occur in two cases: due to a casualty (e.g. a fire) or in normal use conditions (e.g. storage of nuclear rejects). This work aims at contributing to the study of the phenomena that can be observed in concrete exposed to high temperatures and, in particular, focuses on the study of the evolution of intrinsic permeability. The characterisation of permeability (which is hardly measurable in hot conditions) is necessary for describing and modelling transport phenomena which occur in porous media. An experimental study has been made in collaboration with the CEA. A real-scale hollow cylinder has been instrumented with gauges for studying the evolution of temperature and gas pressure fields inside concrete. Later, the cylinder has been then numerically modelled by means of a thermo-hydro-chemical (THC) and a thermo-hydro-chemo-mechanical (THCM) model. The THC model, implemented by means of the finite volume method, has allowed a first, qualitative study of the behaviour of concrete submitted to high temperature. This model, which, for sake of simplicity, has neglected all mechanical effects, has allowed the description of the main phenomena occurring inside concrete: mass transport, phase changes, microstructure evolution. Later, the modelling has been completed by means of the THCM model using the Hitecosp code, implemented by means of the finite element method at the university of Padua. This code allows a very complete description of the phenomena occurring inside concrete and takes into consideration the mechanical behavior of concrete by means of an

  5. Pore network modelling of heavy oil depressurization : a parametric study of factors affecting critical gas saturation and three-phase relative permeabilities

    Energy Technology Data Exchange (ETDEWEB)

    Bondino, I.; McDougall, S.D. [Heriot-Watt Univ., Edinburgh, Scotland (United Kingdom); Hamon, G. [TotalFina Elf Exploration and Production (France)

    2002-07-01

    A review of how the bubble nucleation process affects the efficiency of heavy oil recovery was presented along with a discussion regarding a pore-scale simulator technique to depressurize heavy oil systems. A light oil depressurization simulation is also presented in which a straightforward instantaneous nucleation (IN) model and a more intricate progressive nucleation (PN) model have been used. Simulation results are compared to those derived from the heavy oil systems. The nucleation of bubbles, their growth by solute diffusion and expansion, plus the final stages of coalescence migration and production are the main steps in the depressurization process which were accounted for in a 3-phase simulator. The model can also determine the impact of bubble density and gas-oil diffusion coefficient on critical gas saturation and 3-phase relative permeability. The difference in results for light and heavy oils was also highlighted. In the first scenario, the evolution of gas was characterized by embryonic bubbles that are quickly and randomly nucleated once bubble-point pressure is reached. A stochastic algorithm was developed for PN from experimental observations. IN and PN observations were not necessarily contradictory. It was determined that the high interfacial tension of heavy oils leads to a more compact, capillary-dominated pattern of gas evolution compared to light oils, resulting in improved recoveries for heavy oil systems. 23 refs., 6 tabs., 23 figs.

  6. Shear Stress-Relative Slip Relationship at Concrete Interfaces

    Directory of Open Access Journals (Sweden)

    Keun-Hyeok Yang

    2016-01-01

    Full Text Available This study develops a simple and rational shear stress-relative slip model of concrete interfaces with monolithic castings or smooth construction joints. In developing the model, the initial shear cracking stress and relative slip amount at peak stress were formulated from a nonlinear regression analysis using test data for push-off specimens. The shear friction strength was determined from the generalized equations on the basis of the upper-bound theorem of concrete plasticity. Then, a parametric fitting analysis was performed to derive equations for the key parameters determining the shapes of the ascending and descending branches of the shear stress-relative slip curve. The comparisons of predictions and measurements obtained from push-off tests confirmed that the proposed model provides superior accuracy in predicting the shear stress-relative slip relationship of interfacial shear planes. This was evidenced by the lower normalized root mean square error than those in Xu et al.’s model and the CEB-FIB model, which have many limitations in terms of the roughness of the substrate surface along an interface and the magnitude of equivalent normal stress.

  7. Military-related posttraumatic stress disorder and intimate relationship behaviors: a developing dyadic relationship model.

    Science.gov (United States)

    Gerlock, April A; Grimesey, Jackie; Sayre, George

    2014-07-01

    The protracted conflict in Iraq and Afghanistan and an all-volunteer military has resulted in multiple war zone deployments for many service members. While quick redeployment turnaround has left little time for readjustment for either the service member or family, dealing with the long-term sequelae of combat exposure often leaves families and intimate partners ill-prepared for years after deployments. Using a modified grounded theory approach, digitally recorded couple interviews of 23 couples were purposefully selected from a larger sample of 441 couples to better understand the impact of war zone deployment on the couple. The veteran sample was recruited from a randomly selected cohort of men in treatment for posttraumatic stress disorder (PTSD). Overall, it was found when veterans experiencing deployment-related PTSD reenter or start new intimate relationships they may bring with them a unique cluster of interrelated issues which include PTSD symptoms, physical impairment, high rates of alcohol and/or drug abuse, and psychological and physical aggression. These factors contributed to a dynamic of exacerbating conflict. How these couples approached relationship qualities of mutuality, balanced locus of control and weakness tolerance across six axes of caregiving, disability, responsibility, trauma, communication, and community impacted the couple's capacity to communicate and resolve conflict. This dyadic relationship model is used to help inform implications for clinical practice. © 2013 American Association for Marriage and Family Therapy.

  8. Gas and Water Permeability of Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Villar, M. V.; Martin, P. L.; Romero, F. J.; Gutierrez-Rodirgo, V.; Barcala, J. M.

    2012-11-01

    The gas pressure of concrete samples was measured in an unsteady-state equipment working under low injection pressures and in a newly fine tuned steady-state setup working under different pressures. These measurements allowed the estimation of the intrinsic and relative gas permeability of the concrete and of the effect of boundary conditions on them. Permeability decreased with water content, but it was also greatly affected by the hydraulic history of concrete, i.e. if it had been previously dried or wetted. In particular, and for a given degree of saturation, the gas permeability of concrete previously saturated was lower than if the concrete had been just air dried or saturated after air drying. In any case, the gas permeability was about two orders of magnitude higher than the liquid water permeability (10-16 vs. 10-18 m2), probably due to the chemical reactions taking place during saturation (carbonation). The relative gas permeability of concrete increased sharply for water degrees of saturation smaller than 50%. The boundary conditions also affected the gas permeability, which seemed to be mostly conditioned by the back pressure and the confining pressure, increasing as the former increased and decreasing as the latter increased, i.e. decreasing as the effective pressure increased. Overall the increase of pressure head or injection pressure implied a decrease in gas permeability. External,microcracking during air-drying could not be ruled out as responsible for the decrease of permeability with confining pressure. The apparent permeability obtained applying the Klinkenberg method for a given effective pressure was only slightly smaller than the average of all the values measured for the same confining pressure range. For this reason it is considered that the Klinkenberg effect was not relevant in the range of pressures applied. (Author) 37 refs.

  9. The complex initial reluctivity, permeability and susceptibility spectra of magnetic materials

    Science.gov (United States)

    Hamilton, N. C.

    2015-03-01

    The HF complex permeability spectrum of a magnetic material is deduced from the measured impedance spectrum, which is then normalized to a series permeability spectrum. However, this series permeability spectrum has previously been shown to correspond to a parallel magnetic circuit, which is not appropriate. Some of the implications of this truth are examined. This electric/magnetic duality has frustrated efforts to interpret the shape of the complex magnetic permeability spectra of materials, and has hindered the application of impedance spectroscopy to magnetic materials. In the presence of magnetic loss, the relationship between the relative magnetic permeability and the magnetic susceptibility is called into question. The use of reluctivity spectra for expressing magnetic material properties is advocated. The relative loss factor, tanδm/μi is shown to be an approximation for the imaginary part of the reluctivity. A single relaxation model for the initial reluctivity spectra of magnetic materials is presented, and its principles are applied to measurements of a high permeability ferrite. The results are presented as contour plots of the spectra as a function of temperature.

  10. Romantic Relationship Length and its Perceived Quality: Mediating Role of Facebook-Related Conflict

    Directory of Open Access Journals (Sweden)

    H. M. Saidur Rahaman

    2015-08-01

    Full Text Available The purpose of this study was to investigate how Facebook use is leading to negative relationship outcomes such as cheating and breakup by assessing users’ perceived relationship qualities. It was hypothesized that Facebook-related conflict will be negatively related with users’ relationship length and will also be negatively related with their perceived relationship satisfaction, commitment, and love. Facebook-related conflict further mediates the relationship between relationship length and perceived relationship satisfaction, commitment, and love. Self-report data were gathered from participants (N = 101 in an online survey by employing standard questionnaires. A set of regression and mediation analyses confirmed all the hypotheses of the study. That is, Facebook-related conflict mediates the relationship between relationship length and perceived relationship satisfaction, commitment, and love. Moreover, the magnitude of mediation was highest for relationship satisfaction. Implications for future research and contributions are discussed.

  11. Soils - Mean Permeability

    Data.gov (United States)

    Kansas Data Access and Support Center — This digital spatial data set provides information on the magnitude and spatial pattern of depth-weighted, mean soil permeability throughout the State of Kansas. The...

  12. Hydrogen permeability through metals

    International Nuclear Information System (INIS)

    Pisarev, A.A.; Tsvetkov, I.V.; Marenkov, E.D.; Yarko, S.S.

    2011-01-01

    The mechanisms of hydrogen permeability through one-layer and multi-layer membranes are considered. The effect of surface roughness, crystal defects, cracks and pores is described. Mathematical description of the processes is given [ru

  13. Permeable pavement study (Edison)

    Data.gov (United States)

    U.S. Environmental Protection Agency — While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types...

  14. Length-weight relationships, condition factors and relative weight of ...

    African Journals Online (AJOL)

    The aim of this study was to record the length-weight relationship parameters and condition factors for some commercially important fish of Bushehr coastal waters of Persian Gulf. The length-weight relationships were calculated for five species caught during fishing surveys using different types of fishing gears (trawls, pots ...

  15. microRNA-4516 Contributes to Different Functions of Epithelial Permeability Barrier by Targeting Poliovirus Receptor Related Protein 1 in Enterovirus 71 and Coxsackievirus A16 Infections

    Directory of Open Access Journals (Sweden)

    Yajie Hu

    2018-04-01

    Full Text Available Enterovirus 71 (EV-A71 and coxsackievirus A16 (CV-A16 remain the predominant etiological agents of hand, foot, and mouth disease (HFMD. The clinical manifestations caused by the two viruses are obviously different. CV-A16 usually triggers a repeated infection, and airway epithelial integrity is often the potential causative factor of respiratory repeated infections. Our previous studies have demonstrated that there were some differentially expressed miRNAs involved in the regulation of adhesion function of epithelial barrier in EV-A71 and CV-A16 infections. In this study, we compared the differences between EV-A71 and CV-A16 infections on the airway epithelial barrier function in human bronchial epithelial (16HBE cells and further screened the key miRNA which leaded to the formation of these differences. Our results showed that more rapid proliferation, more serious destruction of 16HBE cells permeability, more apoptosis and disruption of intercellular adhesion-associated molecules were found in CV-A16 infection as compared to EV-A71 infection. Furthermore, we also identified that microRNA-4516 (miR-4516, which presented down-regulation in EV-A71 infection and up-regulation in CV-A16 infection was an important regulator of intercellular junctions by targeting Poliovirus receptor related protein 1(PVRL1. The expressions of PVRL1, claudin4, ZO-1 and E-cadherin in CV-A16-infected cells were significantly less than those in EV-A71-infected cells, while the expressions of these proteins were subverted when pre-treated with miR-4516-overexpression plasmid in EV-A71 infected and miR-4516-knockdown plasmid in CV-A16 infected 16HBE cells. Thus, these data suggested that the opposite expression of miR-4516 in EV-A71 and CV-A16 infections might be the initial steps leading to different epithelial impairments of 16HBE cells by destroying intercellular adhesion, which finally resulted in different outcomes of EV-A71 and CV-A16 infections.

  16. Determination of glucose exchange rates and permeability of erythrocyte membrane in preeclampsia and subsequent oxidative stress-related protein damage using dynamic-{sup 19}F-NMR

    Energy Technology Data Exchange (ETDEWEB)

    Dickinson, Elizabeth, E-mail: elizabeth.dickinson@york.ac.uk [University of York, Department of Chemistry (United Kingdom); Arnold, John R. P. [Selby College (United Kingdom); Fisher, Julie [University of Leeds, School of Chemistry (United Kingdom)

    2017-02-15

    The cause of the pregnancy condition preeclampsia (PE) is thought to be endothelial dysfunction caused by oxidative stress. As abnormal glucose tolerance has also been associated with PE, we use a fluorinated-mimic of this metabolite to establish whether any oxidative damage to lipids and proteins in the erythrocyte membrane has increased cell membrane permeability. Data were acquired using {sup 19}F Dynamic-NMR (DNMR) to measure exchange of 3-fluoro-3-deoxyglucose (3-FDG) across the membrane of erythrocytes from 10 pregnant women (5 healthy control women, and 5 from women suffering from PE). Magnetisation transfer was measured using the 1D selective inversion and 2D EXSY pulse sequences, over a range of time delays. Integrated intensities from these experiments were used in matrix diagonalisation to estimate the values of the rate constants of exchange and membrane permeability. No significant differences were observed for the rate of exchange of 3-FDG and membrane permeability between healthy pregnant women and those suffering from PE, leading us to conclude that no oxidative damage had occurred at this carrier-protein site in the membrane.

  17. Determination of glucose exchange rates and permeability of erythrocyte membrane in preeclampsia and subsequent oxidative stress-related protein damage using dynamic-"1"9F-NMR

    International Nuclear Information System (INIS)

    Dickinson, Elizabeth; Arnold, John R. P.; Fisher, Julie

    2017-01-01

    The cause of the pregnancy condition preeclampsia (PE) is thought to be endothelial dysfunction caused by oxidative stress. As abnormal glucose tolerance has also been associated with PE, we use a fluorinated-mimic of this metabolite to establish whether any oxidative damage to lipids and proteins in the erythrocyte membrane has increased cell membrane permeability. Data were acquired using "1"9F Dynamic-NMR (DNMR) to measure exchange of 3-fluoro-3-deoxyglucose (3-FDG) across the membrane of erythrocytes from 10 pregnant women (5 healthy control women, and 5 from women suffering from PE). Magnetisation transfer was measured using the 1D selective inversion and 2D EXSY pulse sequences, over a range of time delays. Integrated intensities from these experiments were used in matrix diagonalisation to estimate the values of the rate constants of exchange and membrane permeability. No significant differences were observed for the rate of exchange of 3-FDG and membrane permeability between healthy pregnant women and those suffering from PE, leading us to conclude that no oxidative damage had occurred at this carrier-protein site in the membrane.

  18. A drainage data-based calculation method for coalbed permeability

    International Nuclear Information System (INIS)

    Lai, Feng-peng; Li, Zhi-ping; Fu, Ying-kun; Yang, Zhi-hao

    2013-01-01

    This paper establishes a drainage data-based calculation method for coalbed permeability. The method combines material balance and production equations. We use a material balance equation to derive the average pressure of the coalbed in the production process. The dimensionless water production index is introduced into the production equation for the water production stage. In the subsequent stage, which uses both gas and water, the gas and water production ratio is introduced to eliminate the effect of flush-flow radius, skin factor, and other uncertain factors in the calculation of coalbed methane permeability. The relationship between permeability and surface cumulative liquid production can be described as a single-variable cubic equation by derivation. The trend shows that the permeability initially declines and then increases after ten wells in the southern Qinshui coalbed methane field. The results show an exponential relationship between permeability and cumulative water production. The relationship between permeability and cumulative gas production is represented by a linear curve and that between permeability and surface cumulative liquid production is represented by a cubic polynomial curve. The regression result of the permeability and surface cumulative liquid production agrees with the theoretical mathematical relationship. (paper)

  19. Phylogenetic relationships of North American Gomphidae and their close relatives

    Science.gov (United States)

    Intrafamilial relationships among clubtail dragonflies (Gomphidae) have been the subject of many morphological studies, but have not yet been systematically evaluated using molecular data. Here we present the first molecular phylogeny of Gomphidae. We include six of the eight sub...

  20. Biostable glucose permeable polymer

    DEFF Research Database (Denmark)

    2017-01-01

    A new biostable glucose permeable polymer has been developed which is useful, for example, in implantable glucose sensors. This biostable glucose permeable polymer has a number of advantageous characteristics and, for example, does not undergo hydrolytic cleavage and degradation, thereby providing...... a composition that facilitates long term sensor stability in vivo. The versatile characteristics of this polymer allow it to be used in a variety of contexts, for example to form the body of an implantable glucose sensor. The invention includes the polymer composition, sensor systems formed from this polymer...

  1. Permeability of gypsum samples dehydrated in air

    Science.gov (United States)

    Milsch, Harald; Priegnitz, Mike; Blöcher, Guido

    2011-09-01

    We report on changes in rock permeability induced by devolatilization reactions using gypsum as a reference analog material. Cylindrical samples of natural alabaster were dehydrated in air (dry) for up to 800 h at ambient pressure and temperatures between 378 and 423 K. Subsequently, the reaction kinetics, so induced changes in porosity, and the concurrent evolution of sample permeability were constrained. Weighing the heated samples in predefined time intervals yielded the reaction progress where the stoichiometric mass balance indicated an ultimate and complete dehydration to anhydrite regardless of temperature. Porosity showed to continuously increase with reaction progress from approximately 2% to 30%, whilst the initial bulk volume remained unchanged. Within these limits permeability significantly increased with porosity by almost three orders of magnitude from approximately 7 × 10-19 m2 to 3 × 10-16 m2. We show that - when mechanical and hydraulic feedbacks can be excluded - permeability, reaction progress, and porosity are related unequivocally.

  2. Transformable ferroelectric control of dynamic magnetic permeability

    Science.gov (United States)

    Jiang, Changjun; Jia, Chenglong; Wang, Fenglong; Zhou, Cai; Xue, Desheng

    2018-02-01

    Magnetic permeability, which measures the response of a material to an applied magnetic field, is crucial to the performance of magnetic devices and related technologies. Its dynamic value is usually a complex number with real and imaginary parts that describe, respectively, how much magnetic power can be stored and lost in the material. Control of permeability is therefore closely related to energy redistribution within a magnetic system or energy exchange between magnetic and other degrees of freedom via certain spin-dependent interactions. To avoid a high power consumption, direct manipulation of the permeability with an electric field through magnetoelectric coupling leads to high efficiency and simple operation, but remains a big challenge in both the fundamental physics and material science. Here we report unambiguous evidence of ferroelectric control of dynamic magnetic permeability in a Co /Pb (Mg1/3Nb2/3) 0.7Ti0.3O3 (Co/PMN-PT) heterostructure, in which the ferroelectric PMN-PT acts as an energy source for the ferromagnetic Co film via an interfacial linear magnetoelectric interaction. The electric field tuning of the magnitude and line shape of the permeability offers a highly localized means of controlling magnetization with ultralow power consumption. Additionally, the emergence of negative permeability promises a new way of realizing functional nanoscale metamaterials with adjustable refraction index.

  3. RELATIONSHIP COMMITMENT, RELATIONAL EQUITY AND COMPANY IMAGE IN CUSTOMER LOYALTY DEVELOPMENT

    OpenAIRE

    DLAČIĆ, JASMINA; ŽABKAR, VESNA

    2012-01-01

    This paper explores the relationship between customer loyalty and its seldom researched antecedents: relationship commitment, relational equity and company image. The proposed conceptual model is tested with data gained from customers of mobile telephone operators. The results show that relationship commitment and relational equity have a statistically significant positive influence on customer loyalty. In addition, the results of hierarchical multiple regr...

  4. Concentrations of lipopolysaccharide-binding protein, bactericidal/permeability-increasing protein, soluble CD14 and plasma lipids in relation to endotoxaemia in patients with alcoholic liver disease

    DEFF Research Database (Denmark)

    Schäfer, C.; Parlesak, Alexandr; Schütt, C.

    2002-01-01

    of endotoxin on its target cells (LPS-binding protein and sCD14) were increased. Endotoxin antagonists, such as bactericidal/permeability-increasing protein and high-density lipoprotein, were increased in the pre-cirrhotic stages, whereas a significant reduction of the latter was observed in cirrhosis. Low......-density lipoprotein remained unchanged. The elevation of binding factors in the pre-cirrhotic stages of alcoholic liver disease might attenuate the effects of endotoxaemia, whereas in cirrhosis the reduction of high density lipoprotein, to which large quantities of endotoxin bind, may contribute to its pro...

  5. Negative permeability from random particle composites

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Shahid, E-mail: shussain2@qinetiq.com

    2017-04-15

    Artificial media, such as those composed of periodically-spaced wires for negative permittivity and split ring resonators for negative permeability have been extensively investigated for negative refractive index (NRI) applications (Smith et al., 2004; Pendry et al., 1999) [1,2]. This paper presents an alternative method for producing negative permeability: granular (or particulate) composites incorporating magnetic fillers. Artificial media, such as split-ring resonators, are designed to produce a magnetic resonance feature, which results in negative permeability over a narrow frequency range about the resonance frequency. The position of the feature is dependent upon the size of the inclusion. The material in this case is anisotropic, such that the feature is only observable when the materials are orientated in a specific direction relative to the applied field. A similar resonance can be generated in magnetic granular (particulate) materials: ferromagnetic resonance from the natural spin resonance of particles. Although the theoretical resonance profiles in granular composites shows the permeability dipping to negative values, this is rarely observed experimentally due to resonance damping effects. Results are presented for iron in spherical form and in flake form, dispersed in insulating host matrices. The two particle shapes show different permeability performance, with the magnetic flakes producing a negative contribution. This is attributed to the stronger coupling with the magnetic field resulting from the high aspect ratio of the flakes. The accompanying ferromagnetic resonance is strong enough to overcome the effects of damping and produce negative permeability. The size of random particle composites is not dictated by the wavelength of the applied field, so the materials are potentially much thinner than other, more traditional artificial composites at microwave frequencies. - Highlights: • Negative permeability from random particle composites is

  6. In vivo human buccal permeability of nicotine

    DEFF Research Database (Denmark)

    Adrian, Charlotte L; Olin, Helle B D; Dalhoff, Kim

    2006-01-01

    The aim was to examine the in vivo buccal pH-dependent permeability of nicotine in humans and furthermore compare the in vivo permeability of nicotine to previous in vitro permeability data. The buccal permeability of nicotine was examined in a three-way cross-over study in eight healthy non......-smokers using a buccal perfusion cell. The disappearance of nicotine from perfusion solutions with pH 6.0, 7.4, and 8.1 was studied for 3h. The apparent permeability of nicotine (P(app)) was determined at each pH value. Parotid saliva was collected in an attempt to assess systemic levels of nicotine....... The disappearance rate of nicotine increased significantly as the pH increased, which resulted in P(app) values of 0.57+/-0.55 x 10(-4), 2.10+/-0.23 x 10(-4), and 3.96+/-0.54 x 10(-4)cms(-1) (mean+/-S.D.) at pH 6.0, 7.4, and 8.1, respectively. A linear relationship (R(2)=0.993) was obtained between the P...

  7. Kinetics of the flash-induced P515 response in relation to the H+-permeability of the membrane bound ATPase in spinach chloroplasts

    Energy Technology Data Exchange (ETDEWEB)

    Peters, R.L.; van Kooten, O.; Vredenberg, W.J.

    1985-08-01

    The effect of dicyclohexylcarbodiimide (DCCD) on the kinetics of the flash-induced P515 response and on the activity of the ATPase was investigated in isolated spinach chloroplasts. It was found that after the addition of 5 X 10(-8)mol DCCD the rate of ATP hydrolysis induced by a period of 60 sec illumination was decreased to less than 5% of its original value. At this concentration, hardly any effect, if at all, could be detected on the kinetics of the flash-induced P515 response, neither in dark-adapted nor in light-activated chloroplasts. It was concluded that the presence of concentrations of DCCD, sufficiently high to affect the ATPase activity, does not affect the kinetics of the flash-induced P515 response. Since DCCD decreases the H+ permeability of the membrane-bound ATPase, it was concluded that this permeability coefficient for protons is not an important factor in the regulation of the flash-induced membrane potential and, therefore, does not affect the kinetics of the flash-induced P515 response.

  8. Influence of N deficiency and salinity on metal (Pb, Zn and Cu) accumulation and tolerance by Rhizophora stylosa in relation to root anatomy and permeability

    International Nuclear Information System (INIS)

    Cheng Hao; Wang Youshao; Ye Zhihong; Chen Danting; Wang Yutu; Peng Yalan; Wang Liying

    2012-01-01

    Effects of N deficiency and salinity on root anatomy, permeability and metal (Pb, Zn and Cu) translocation and tolerance were investigated using mangrove seedlings of Rhizophora stylosa. The results showed that salt could directly reduce radial oxygen loss (ROL) by stimulation of lignification within exodermis. N deficiency, oppositely, would reduce lignification. Such an alteration in root permeability may also influence metal tolerance by plants. The data indicated that a moderate salinity could stimulate a lignified exodermis that delayed the entry of metals into the roots and thereby contributed to a higher metal tolerance, while N deficiency would aggravate metal toxicity. The results from sand pot trail further confirmed this issue. This study provides a barrier property of the exodermis in dealing with environments. The plasticity of root anatomy is likely an adaptive strategy to regulate the fluxes of gases, nutrients and toxins at root–soil interface. - Highlights: ► Salt induced lignified exodermis which slowed down metal entry into the plants. ► N deficiency, oppositely, aggravated metal mobility and toxicity. ► Barrier properties of the exodermis. - N deficiency and salinity regulate the apoplastic transport barrier of metals and their toxicities

  9. Role of endothelial permeability hotspots and endothelial mitosis in determining age-related patterns of macromolecule uptake by the rabbit aortic wall near branch points.

    Science.gov (United States)

    Chooi, K Yean; Comerford, Andrew; Cremers, Stephanie J; Weinberg, Peter D

    2016-07-01

    Transport of macromolecules between plasma and the arterial wall plays a key role in atherogenesis. Scattered hotspots of elevated endothelial permeability to macromolecules occur in the aorta; a fraction of them are associated with dividing cells. Hotspots occur particularly frequently downstream of branch points, where lesions develop in young rabbits and children. However, the pattern of lesions varies with age, and can be explained by similar variation in the pattern of macromolecule uptake. We investigated whether patterns of hotspots and mitosis also change with age. Evans' Blue dye-labeled albumin was injected intravenously into immature or mature rabbits and its subsequent distribution in the aortic wall around intercostal branch ostia examined by confocal microscopy and automated image analysis. Mitosis was detected by immunofluorescence after adding 5-bromo-2-deoxiuridine to drinking water. Hotspots were most frequent downstream of branches in immature rabbits, but a novel distribution was observed in mature rabbits. Neither pattern was explained by mitosis. Hotspot uptake correlated spatially with the much greater non-hotspot uptake (p hotspots were considered. The pattern of hotspots changes with age. The data are consistent with there being a continuum of local permeabilities rather than two distinct mechanisms. The distribution of the dye, which binds to elastin and collagen, was similar to that of non-binding tracers and to lesions apart from a paucity at the lateral margins of branches that can be explained by lower levels of fibrous proteins in those regions. Copyright © 2016. Published by Elsevier Ireland Ltd.

  10. Permeability and compression characteristics of municipal solid waste samples

    Science.gov (United States)

    Durmusoglu, Ertan; Sanchez, Itza M.; Corapcioglu, M. Yavuz

    2006-08-01

    Four series of laboratory tests were conducted to evaluate the permeability and compression characteristics of municipal solid waste (MSW) samples. While the two series of tests were conducted using a conventional small-scale consolidometer, the two others were conducted in a large-scale consolidometer specially constructed for this study. In each consolidometer, the MSW samples were tested at two different moisture contents, i.e., original moisture content and field capacity. A scale effect between the two consolidometers with different sizes was investigated. The tests were carried out on samples reconsolidated to pressures of 123, 246, and 369 kPa. Time settlement data gathered from each load increment were employed to plot strain versus log-time graphs. The data acquired from the compression tests were used to back calculate primary and secondary compression indices. The consolidometers were later adapted for permeability experiments. The values of indices and the coefficient of compressibility for the MSW samples tested were within a relatively narrow range despite the size of the consolidometer and the different moisture contents of the specimens tested. The values of the coefficient of permeability were within a band of two orders of magnitude (10-6-10-4 m/s). The data presented in this paper agreed very well with the data reported by previous researchers. It was concluded that the scale effect in the compression behavior was significant. However, there was usually no linear relationship between the results obtained in the tests.

  11. Relational Aggression in Sibling and Peer Relationships during Early Childhood

    Science.gov (United States)

    Ostrov, Jamie M.; Crick, Nicki R.; Stauffacher, Kirstin

    2006-01-01

    The role of siblings ("N" = 50) in the display of physical and relational aggression among peers during early childhood was explored. Specifically, sibling pairs' rates of physical and relational aggression were assessed in their independent social contexts. Findings indicated low to moderate levels of intercorrelation between physical and…

  12. Parent-child interactions and relational aggression in peer relationships

    NARCIS (Netherlands)

    Michiels, Daisy; Grietens, Hans; Onghena, Patrick; Kuppens, Sofie

    2008-01-01

    The major aim of this review is to propose new ways of thinking about the role of parents in the development and course of children's relationally aggressive behavior. An important theoretical framework from which to start thinking about linkages between parenting and relational aggression is

  13. The relationship between psychopathy and crime-related amnesia

    NARCIS (Netherlands)

    Cima-Knijff, M.J.; van Oorsouw, K.

    2013-01-01

    The objective of this study was to investigate whether levels of psychopathy predicted claims of crime-related amnesia. Different characteristics of psychopathy were based on the factor structure of the self-report questionnaire Psychopathic Personality Inventory (PPI). Crime-related amnesia claims

  14. A Review of Permeable Pavement Clogging Investigations and Recommended Maintenance Regimes

    Directory of Open Access Journals (Sweden)

    Mostafa Razzaghmanesh

    2018-03-01

    Full Text Available Understanding clogging mechanisms in permeable pavements can help optimize the required maintenance regime. In this review paper, methods for investigating clogging mechanisms are described. These include surface infiltration methods, the use of embedded sensors, and the development of modelling tools. Previously conducted surface infiltration tests indicate the importance of the age of a permeable pavement system and also local climatic conditions, including rainfall intensity. The results indicate that porous concrete generally has the highest infiltration capacity and this is followed by permeable interlocking concrete pavement and then porous asphalt. The measured infiltration rates decreased significantly even within two years of installation. There was an indirect relationship between surface infiltration rates and the age of the pavements. It was also found that the rainfall characteristics are important in selecting the type of pavement. Sensor technologies have been used mainly in the United States and there has been a reluctance to use such technologies in other parts of the world. Few studies have been conducted into modelling the changing performance of permeable pavement systems over time and there is a need to develop more general models. Various methods and machinery have been developed for cleaning and maintaining permeable pavements and there is no universally preferred approach currently available. Indeed, several of the commonly used maintenance methods have been shown to be relatively ineffective.

  15. Controlling DC permeability in cast steels

    International Nuclear Information System (INIS)

    Sumner, Aaran; Gerada, Chris; Brown, Neil; Clare, Adam

    2017-01-01

    Annealing (at multiple cooling rates) and quenching (with tempering) was performed on specimens of cast steel of varying composition. The aim was to devise a method for selecting the steel with the highest permeability, from any given range of steels, and then increasing the permeability by heat treatment. Metallographic samples were imaged using optical microscopy to show the effect of the applied heat treatments on the microstructure. Commonly cast steels can have DC permeability altered by the careful selection of a heat treatment. Increases of up to 381% were achieved by annealing using a cooling rate of 6.0 °C/min. Annealing was found to cause the carbon present in the steel to migrate from grain boundaries and from within ferrite crystals into adjacent pearlite crystals. The migration of the carbon resulted in less carbon at grain boundaries and within ferrite crystals reducing the number of pinning sites between magnetic domains. This gives rise to a higher permeability. Quenching then tempering was found to cause the formation of small ferrite crystals with the carbon content of the steel predominately held in the martensitic crystal structures. The results show that with any given range of steel compositions the highest baseline DC permeability will be found with the steel that has the highest iron content and the lowest carbon content. For the samples tested in this paper a cooling rate of 4.5 °C/min resulted in the relative permeability of the sample with the highest baseline permeability, AS4, increasing from 783 to 1479 at 0.5 T. This paper shows how heat treatments commonly applied to hypoeutectoid cast steels, to improve their mechanical performance, can be used to also enhance electromagnetic properties of these alloys. The use of cast steels allows the creation of DC components for electrical machines not possible by the widely used method of stacking of electrical grade sheet steels. - Highlights: • A range of structural steels had their

  16. Controlling DC permeability in cast steels

    Energy Technology Data Exchange (ETDEWEB)

    Sumner, Aaran, E-mail: aaran.sumner@nottingham.ac.uk [University of Nottingham, Nottingham University Park Campus, Nottingham NG7 2RD, England (United Kingdom); Gerada, Chris, E-mail: chris.gerada@nottingham.ac.uk [Electrical Machines, University of Nottingham, Tower Building, Nottingham NG7 2RD, England (United Kingdom); Brown, Neil, E-mail: neil.brown@cummins.com [Advanced Electrical Machines Research and Technology at Cummins Power Generation, Peterborough PE2 6FZ, England (United Kingdom); Clare, Adam, E-mail: adam.clare@nottingham.ac.uk [Advanced Manufacturing, University of Nottingham, University Park Campus, Nottingham NG7 2RD, England (United Kingdom)

    2017-05-01

    Annealing (at multiple cooling rates) and quenching (with tempering) was performed on specimens of cast steel of varying composition. The aim was to devise a method for selecting the steel with the highest permeability, from any given range of steels, and then increasing the permeability by heat treatment. Metallographic samples were imaged using optical microscopy to show the effect of the applied heat treatments on the microstructure. Commonly cast steels can have DC permeability altered by the careful selection of a heat treatment. Increases of up to 381% were achieved by annealing using a cooling rate of 6.0 °C/min. Annealing was found to cause the carbon present in the steel to migrate from grain boundaries and from within ferrite crystals into adjacent pearlite crystals. The migration of the carbon resulted in less carbon at grain boundaries and within ferrite crystals reducing the number of pinning sites between magnetic domains. This gives rise to a higher permeability. Quenching then tempering was found to cause the formation of small ferrite crystals with the carbon content of the steel predominately held in the martensitic crystal structures. The results show that with any given range of steel compositions the highest baseline DC permeability will be found with the steel that has the highest iron content and the lowest carbon content. For the samples tested in this paper a cooling rate of 4.5 °C/min resulted in the relative permeability of the sample with the highest baseline permeability, AS4, increasing from 783 to 1479 at 0.5 T. This paper shows how heat treatments commonly applied to hypoeutectoid cast steels, to improve their mechanical performance, can be used to also enhance electromagnetic properties of these alloys. The use of cast steels allows the creation of DC components for electrical machines not possible by the widely used method of stacking of electrical grade sheet steels. - Highlights: • A range of structural steels had their

  17. Collaborative Procurement: A Relational View of Buyer–Buyer Relationships

    NARCIS (Netherlands)

    Walker, H.; Schotanus, Fredo; Bakker, E.; Harland, C.

    2013-01-01

    Collaborative procurement is increasingly on the policy agenda in many countries, yet problems with collaboration occur. This article adopts a relational theory perspective to explore the enablers of and barriers to collaboration in purchasing, helping identify success factors. The authors adopted a

  18. Examining the relation between adolescent social anxiety, adolescent delinquency (abstention), and emerging adulthood relationship quality

    NARCIS (Netherlands)

    Mercer, N.; Crocetti, E; Meeus, W.H.J.; Branje, S

    2017-01-01

    Background and Objectives: Social anxiety symptoms and delinquency are two prevalent manifestations of problem behavior during adolescence and both are related to negative interpersonal relationships in adolescence and emerging adulthood. This study examined the relation between social anxiety and

  19. Examining the Relation Between Adolescent Social Anxiety, Adolescent Delinquency (Abstention), and Emerging Adulthood Relationship Quality

    NARCIS (Netherlands)

    Mercer, Natalie; Crocetti, Elisabetta; Meeus, Wim; Branje, Susan

    2017-01-01

    BACKGROUND AND OBJECTIVES: Social anxiety symptoms and delinquency are two prevalent manifestations of problem behavior during adolescence and both are related to negative interpersonal relationships in adolescence and emerging adulthood. This study examined the relation between social anxiety and

  20. Study on road surface source pollution controlled by permeable pavement

    Science.gov (United States)

    Zheng, Chaocheng

    2018-06-01

    The increase of impermeable pavement in urban construction not only increases the runoff of the pavement, but also produces a large number of Non-Point Source Pollution. In the process of controlling road surface runoff by permeable pavement, a large number of particulate matter will be withheld when rainwater is being infiltrated, so as to control the source pollution at the source. In this experiment, we determined the effect of permeable road surface to remove heavy pollutants in the laboratory and discussed the related factors that affect the non-point pollution of permeable pavement, so as to provide a theoretical basis for the application of permeable pavement.

  1. Molecular relationships between closely related strains and species of nematodes

    Science.gov (United States)

    Butler, M. H.; Wall, S. M.; Luehrsen, K. R.; Fox, G. E.; Hecht, R. M.

    1981-01-01

    Electrophoretic comparisons have been made for 24 enzymes in the Bergerac and Bristol strains of Caenorhabditis elegans and the related species, Caenorhabditis briggsae. No variation was detected between the two strains of C. elegans. In contrast, the two species, C. elegans and C. briggsae exhibited electrophoretic differences in 22 of 24 enzymes. A consensus 5S rRNA sequence was determined for C. elegans and found to be identical to that from C. briggsae. By analogy with other species with relatively well established fossil records it can be inferred that the time of divergence between the two nematode species is probably in the tens of millions of years. The limited anatomical evolution during a time period in which proteins undergo extensive changes supports the hypothesis that anatomical evolution is not dependent on overall protein changes.

  2. Relational Aggression in Peer and Dating Relationships: Links to Psychological and Behavioral Adjustment

    Science.gov (United States)

    Ellis, Wendy E.; Crooks, Claire V.; Wolfe, David A.

    2009-01-01

    We examined the contribution of relational aggression in adolescents' peer and dating relationships to their psychological and behavioral adjustment. In the Fall and again four months later, 1279 (646 female) grade 9 students reported on relational aggression perpetration and victimization in their romantic and peer relationships,…

  3. Profiles and Correlates of Relational Aggression in Young Adults' Romantic Relationships

    Science.gov (United States)

    Goldstein, Sara E.; Chesir-Teran, Daniel; McFaul, Adrienne

    2008-01-01

    The present study examines prevalence and correlates of experiencing and perpetrating relational aggression in the context of young adults' romantic relationships. We assess correlates of relational aggression in four domains of risk: (1) Social-cognitive, (2) Relationship, (3) Trait/dispositional, and (4) Mental health. Results indicate that…

  4. Application of relative permeability modifier additives to reduce water production in different formations; Aplicacao de aditivos modificadores de permeabilidade relativa para reducao da producao de agua em diferentes formacoes

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Ricardo C.B.; Torres, Ricardo S.; Pedrosa Junior, Helio; Dean, Gregory [BJ Services do Brasil Ltda., RJ (Brazil)

    2004-07-01

    Today most oil companies would be better described as water companies. Total worldwide oil production averages some 75 million barrels per day and, while estimates vary, this is associated with the production of 300 - 400 million barrels of water per day. These values of approximately 5 - 6 barrels of water for every barrel of oil are quite conservative. In the United States, where many fields are depleted, the ratio of water-to-oil production is closer to 9 to 1. In some areas around the world, fields remain on production when the ratio is as high as 48 to 1. Numerous strategies, both mechanical and chemical, have been employed over the years in attempts to achieve reduction in water production. Simple shut-off techniques, using cement, mechanical plugs and cross-linked gels have been widely used. Exotic materials such as DPR (disproportionate permeability reducers) and or new generation of relative permeability modifiers (RPM) have been applied in radial treatments with varying degrees of success. Most recently 'Conformance Fracturing' operations have increased substantially in mature fields as the synergistic effect obtained by adding a RPM to a fracturing fluid have produced increased oil production with reduced water cut in one step, consequently eliminating the cost of additional water shut off treatment later on. This paper presents laboratory testing and worldwide case histories of applications of various RPM materials, at different permeability and temperatures. The paper also describes technical design and operational methodology that we believe to have a significant impact in the development strategies of many fields worldwide. (author)

  5. Permeability measuremens of brazilian Eucalyptus

    Directory of Open Access Journals (Sweden)

    Marcio Rogério da Silva

    2010-09-01

    Full Text Available The permeability of Brazilian Eucalyptus grandis and Eucalyptus citriodora wood was measured in a custom build gas analysis chamber in order to determine which species could be successfully treated with preservatives. Liquid permeability was tested using an emulsion of Neen oil and a control of distillated water. Air was used to test the gas phase permeability. For both Eucalyptus grandis and Eucalyptus citriodora, the longitudinal permeability of gas was shown to be about twice as great as the liquid phase permeability. No radial permeability was observed for either wood. The permeability of air and water through the sapwood of Eucalyptus grandis was greater than that through the sapwood of Eucalyptus citriodora. The permeability of neen oil preservative through the sapwood of Eucalyptus grandis was also greater than through the sapwood of E. Citradora, but the difference was not statistically significant. Scanning Electron Microscopy images showed that the distribution and obstruction in the vessels could be correlated with observed permeability properties. Irrespective of the causes of differences in permeability between the species, the fluid phase flux through the sapwood of both species was significant, indicating that both Eucalyptus grandis and Eucalyptus citriodora could be successfully treated with wood preservative.

  6. Predicting Romantic Involvement, Relationship Cognitions, and Relationship Qualities from Physical Appearance, Perceived Norms, and Relational Styles regarding Friends and Parents

    Science.gov (United States)

    Furman, Wyndol; Winkles, Jessica K.

    2010-01-01

    Using a sample of 199 adolescents, the present study examined Furman and Wehner's (1999) hypothesis that the predictors of the degree of romantic involvement and the predictors of romantic relationship cognitions and qualities differ. As hypothesized, physical appearance and friends' normative romantic involvement were related to the degree of…

  7. Assessment of vascularity and permeability in brain tumor using SPECT and [sup 99m]Tc-DTPA-human serum albumin in relation to [sup 201]Tl SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawara, Jyoji; Fukuoka, Seiji; Takahashi, Shuhei; Takahashi, Masaaki; Satoh, Katsuyasu; Suematsu, Katsumi; Nakamura, Jun-ichi (Nakamura Memorial Hospital, Sapporo (Japan))

    1994-02-01

    Single photon emission computed tomography (SPECT) using technetium-99m-DTPA-human serum albumin ([sup 99m]Tc-HSA-D) and thallium-201 chloride ([sup 201]Tl) was simultaneously performed on 25 patients with brain tumors; 10 with brain metastasis, 8 with astrocytoma (Gr. 3) and 7 with meningioma. The early image was obtained 10 minutes after [sup 99m]Tc-HSA-D (740 MBq) injection, and the delayed image was taken 5 hours after the injection. HSA-D index, based on the ratio of [sup 99m]Tc-HSA-D uptake in the tumor versus the cortical area, was calculated on each image, and compared with Tl index (tumor/contralateral cerebrum ratio). HSA-D delayed index was significantly greater than HSA-D early index in all tumor types (p<0.05 by the Wilcoxon ranked sign test). Linear correlation between HSA-D early index and HSA-D delayed index was significant in astrocytoma (GR. 3) (p<0.01) and meningioma (p<0.001), and a linear correlation between HSA-D delayed index and Tl index was significant in astrocytoma (Gr. 3) (p<0.05). It is concluded that HSA-D early index and delayed index could reflect tumor vascularity and permeability, respectively, and provide supplementary information for Tl index. (author).

  8. The role of python eggshell permeability dynamics in a respiration-hydration trade-off.

    Science.gov (United States)

    Stahlschmidt, Zachary R; Heulin, Benoit; DeNardo, Dale F

    2010-01-01

    Parental care is taxonomically widespread because it improves developmental conditions and thus fitness of offspring. Although relatively simplistic compared with parental behaviors of other taxa, python egg-brooding behavior exemplifies parental care because it mediates a trade-off between embryonic respiration and hydration. However, because egg brooding increases gas-exchange resistance between embryonic and nest environments and because female pythons do not adjust their brooding behavior in response to the increasing metabolic requirements of developing offspring, python egg brooding imposes hypoxic costs on embryos during the late stages of incubation. We conducted a series of experiments to determine whether eggshells coadapted with brooding behavior to minimize the negative effects of developmental hypoxia. We tested the hypotheses that python eggshells (1) increase permeability over time to accommodate increasing embryonic respiration and (2) exhibit permeability plasticity in response to chronic hypoxia. Over incubation, we serially measured the atomic and structural components of Children's python (Antaresia childreni) eggshells as well as in vivo and in vitro gas exchange across eggshells. In support of our first hypothesis, A. childreni eggshells exhibited a reduced fibrous layer, became more permeable, and facilitated greater gas exchange as incubation progressed. Our second hypothesis was not supported, as incubation O(2) concentration did not affect the shells' permeabilities to O(2) and H(2)O vapor. Our results suggest that python eggshell permeability changes during incubation but that the alterations over time are fixed and independent of environmental conditions. These findings are of broad evolutionary interest because they demonstrate that, even in relatively simple parental-care models, successful parent-offspring relationships depend on adjustments made by both the parent (i.e., egg-brooding behavioral shifts) and the offspring (i

  9. Active intestinal drug absorption and the solubility-permeability interplay.

    Science.gov (United States)

    Porat, Daniel; Dahan, Arik

    2018-02-15

    The solubility-permeability interplay deals with the question: what is the concomitant effect on the drug's apparent permeability when increasing the apparent solubility with a solubility-enabling formulation? The solubility and the permeability are closely related, exhibit certain interplay between them, and ongoing research throughout the past decade shows that treating the one irrespectively of the other may be insufficient. The aim of this article is to provide an overview of the current knowledge on the solubility-permeability interplay when using solubility-enabling formulations for oral lipophilic drugs, highlighting active permeability aspects. A solubility-enabling formulation may affect the permeability in opposite directions; the passive permeability may decrease as a result of the apparent solubility increase, according to the solubility-permeability tradeoff, but at the same time, certain components of the formulation may inhibit/saturate efflux transporters (when relevant), resulting in significant apparent permeability increase. In these cases, excipients with both solubilizing and e.g. P-gp inhibitory properties may lead to concomitant increase of both the solubility and the permeability. Intelligent development of such formulation will account for the simultaneous effects of the excipients' nature/concentrations on the two arms composing the overall permeability: the passive and the active arms. Overall, thorough mechanistic understanding of the various factors involved in the solubility-permeability interplay may allow developing better solubility-enabling formulations, thereby exploiting the advantages analyzed in this article, offering oral delivery solution even for BCS class IV drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Object and subject relations in adulthood--towards an integrative model of interpersonal relationships.

    Science.gov (United States)

    Zvelc, Gregor

    2010-12-01

    In the article the author presents a model of interpersonal relationships based on integration of object relations theory and theory of attachment. He proposes three main bipolar dimensions of interpersonal relationships: Independence - Dependence, Connectedness - Alienation and Reciprocity - Self-absorption. The author also proposes that it is important to distinguish between two main types of adult interpersonal relationships: object and subject relations. Object relations describe relationships in which the other person is perceived as an object that serves the satisfaction of the first person's needs. Object relations are a manifestation of the right pole of the three main dimensions of interpersonal relationships (Dependence, Alienation and Self-absorption). Subject relations are a counter-pole to the concept of object relations. They describe relationships with other people who are experienced as subjects with their own wishes, interests and needs. Subject relations are a manifestation of the left pole of the main dimensions (Independence, Connectedness and Reciprocity). In this article the author specifically focuses on definitions of object relations in adulthood through a description of six sub-dimensions of object relations: Symbiotic Merging, Separation Anxiety, Social Isolation, Fear of Engulfment, Egocentrism and Narcissism. Every sub-dimension is described in connection to adaptive and pathological functioning. Further research is needed to test the clinical and scientific validity of the model.

  11. Soil radium, soil gas radon and indoor radon empirical relationships to assist in post-closure impact assessment related to near-surface radioactive waste disposal.

    Science.gov (United States)

    Appleton, J D; Cave, M R; Miles, J C H; Sumerling, T J

    2011-03-01

    Least squares (LS), Theil's (TS) and weighted total least squares (WTLS) regression analysis methods are used to develop empirical relationships between radium in the ground, radon in soil and radon in dwellings to assist in the post-closure assessment of indoor radon related to near-surface radioactive waste disposal at the Low Level Waste Repository in England. The data sets used are (i) estimated ²²⁶Ra in the < 2 mm fraction of topsoils (eRa226) derived from equivalent uranium (eU) from airborne gamma spectrometry data, (ii) eRa226 derived from measurements of uranium in soil geochemical samples, (iii) soil gas radon and (iv) indoor radon data. For models comparing indoor radon and (i) eRa226 derived from airborne eU data and (ii) soil gas radon data, some of the geological groupings have significant slopes. For these groupings there is reasonable agreement in slope and intercept between the three regression analysis methods (LS, TS and WTLS). Relationships between radon in dwellings and radium in the ground or radon in soil differ depending on the characteristics of the underlying geological units, with more permeable units having steeper slopes and higher indoor radon concentrations for a given radium or soil gas radon concentration in the ground. The regression models comparing indoor radon with soil gas radon have intercepts close to 5 Bq m⁻³ whilst the intercepts for those comparing indoor radon with eRa226 from airborne eU vary from about 20 Bq m⁻³ for a moderately permeable geological unit to about 40 Bq m⁻³ for highly permeable limestone, implying unrealistically high contributions to indoor radon from sources other than the ground. An intercept value of 5 Bq m⁻³ is assumed as an appropriate mean value for the UK for sources of indoor radon other than radon from the ground, based on examination of UK data. Comparison with published data used to derive an average indoor radon: soil ²²⁶Ra ratio shows that whereas the published data are

  12. Quantitation of small intestinal permeability during normal human drug absorption

    OpenAIRE

    Levitt, David G

    2013-01-01

    Background Understanding the quantitative relationship between a drug?s physical chemical properties and its rate of intestinal absorption (QSAR) is critical for selecting candidate drugs. Because of limited experimental human small intestinal permeability data, approximate surrogates such as the fraction absorbed or Caco-2 permeability are used, both of which have limitations. Methods Given the blood concentration following an oral and intravenous dose, the time course of intestinal absorpti...

  13. Using artificial intelligence to predict permeability from petrographic data

    Energy Technology Data Exchange (ETDEWEB)

    Maqsood Ali; Adwait Chawathe [New Mexico Petroleum Recovery Research Centre (Mexico)

    2000-10-01

    Petrographic data collected during thin section analysis can be invaluable for understanding the factors that control permeability distribution. Reliable prediction of permeability is important for reservoir characterization. The petrographic elements (mineralogy, porosity types, cements and clays, and pore morphology) interact with each other uniquely to generate a specific permeability distribution. It is difficult to quantify accurately this interaction and its consequent effect on permeability, emphasizing the non-linear nature of the process. To capture these non-linear interactions, neural networks were used to predict permeability from petrographic data. The neural net was used as a multivariate correlative tool because of its ability to learn the non-linear relationships between multiple input and output variables. The study was conducted on the upper Queen formation called the Shattuck Member (Permian age). The Shattuck Member is composed of very fine-grained arkosic sandstone. The core samples were available from the Sulimar Queen and South Lucky Lake fields located in Chaves County, New Mexico. Nineteen petrographic elements were collected for each permeability value using a combined minipermeameter-petrographic technique. In order to reduce noise and overfitting the permeability model, these petrographic elements were screened, and their control (ranking) with respect to permeability was determined using fuzzy logic. Since the fuzzy logic algorithm provides unbiased ranking, it was used to reduce the dimensionality of the input variables. Based on the fuzzy logic ranking, only the most influential petrographic elements were selected as inputs for permeability prediction. The neural net was trained and tested using data from Well 1-16 in the Sulimar Queen field. Relying on the ranking obtained from the fuzzy logic analysis, the net was trained using the most influential three, five, and ten petrographic elements. A fast algorithm (the scaled conjugate

  14. Influence of demagnetizing field on the permeability of soft magnetic composites

    International Nuclear Information System (INIS)

    Lin, G.Q.; Li, Z.W.; Chen, Linfeng; Wu, Y.P.; Ong, C.K.

    2006-01-01

    The influence of demagnetizing field on the effective permeability of magnetic composites has been investigated. A theoretical expression of the effective permeability has been obtained and discussed according to four typical composites with spheres, needles, flakes, and aligned prolate ellipsoidal particles. The results indicate that the demagnetizing field within the particles can reduce the effective permeability significantly. In order to increase the effective permeability, it is necessary to decrease the demagnetizing field within the particles. A linear relationship between effective permeability and volume fraction is also observed for composites filled with spherical particles at low volume fraction

  15. The theory of interpersonal relations applied to the preceptor-new graduate relationship.

    Science.gov (United States)

    Washington, Georgita T

    2013-01-01

    This article presents research results applying Peplau's Theory of Interpersonal Relations to the preceptor-new graduate relationship and describes implications for successful transition. These results will help nursing professional development educators with more appropriate preparation and assignment of preceptors.

  16. Effect of permeability enhancers on paracellular permeability of acyclovir.

    Science.gov (United States)

    Ates, Muge; Kaynak, Mustafa Sinan; Sahin, Selma

    2016-06-01

    According to Biopharmaceutics Classification System (BCS), acyclovir is a class III (high solubility, low permeability) compound, and it is transported through paracellular route by passive diffusion. The aim of this study was to investigate the effect of various pharmaceutical excipients on the intestinal permeability of acyclovir. The single-pass in-situ intestinal perfusion (SPIP) method was used to estimate the permeability values of acyclovir and metoprolol across different intestinal segments (jejunum, ileum and colon). Permeability coefficient (Peff ) of acyclovir was determined in the absence and presence of a permeation enhancer such as dimethyl β-cyclodextrin (DM-β-CD), sodium lauryl sulfate (SLS), sodium caprate (Cap-Na) and chitosan chloride. All enhancers increased the permeability of paracellularly transported acyclovir. Although Cap-Na has the highest permeability-enhancing effect in all segments, permeation-enhancing effect of chitosan and SLS was only significant in ileum. On the other hand, DM-β-CD slightly decreased the permeability in all intestinal segments. These findings have potential implication concerning the enhancement of absorption of paracellularly transported compounds with limited oral bioavailability. In the case of acyclovir, Cap-Na either alone or in combination with SLS or chitosan has the potential to improve its absorption and bioavailability and has yet to be explored. © 2016 Royal Pharmaceutical Society.

  17. Matrix injection of relative permeability modifier for water control applied in Brazil basins; Injecao matricial de modificadores de permeabilidade relativa para controle de producao de agua aplicado nas bacias petroliferas brasileiras

    Energy Technology Data Exchange (ETDEWEB)

    Marchi, Flavio; Stefan, Rodolfo; Mendonca, Paulo; Ferreira, Antonio; Silva, Charles; Fonseca, Ana Isoila [BJ Services do Brasil Ltda., Macae, Rio de Janeiro, RJ (Brazil); Melo, Ricardo C.B. [BJ Services Company Africa Ltd., Angola (Angola)

    2008-07-01

    One of the biggest challenges for the oil industry, even at the beginning of well's production, and principally when the well is producing, is how to reduce and handling the produced water on this process. A conservative estimation says for each barrel of produced oil you have 5 or 6 barrels of formation's water. Some factors must be considerable to establish and maintain a carefully management of this effluent, for example the volume of produced water, which is always growing due to the reservoir maturation and for the secondary recovery process; salt content; residual oil and chemical products presence. Water production is the cause of several problems on wells, like scales, organic deposits or starting the process of formation's sand production induced by fines migration. As a consequence, a cost increment of production is observed due to hydrocarbon/water separation and destination of produced water. The same way, is extremely expensive to manage the even bigger volume, which demands efforts to re-inject the water, treatment which avoid or minimize possible environment impacts, development of new equipment and materials which helps and resists to the effects of produced water. Not inherent reservoir's cause can be several, like bad isolated water zones by cement fail, wrong determination of perforated interval, which is easier to use aid methods. When the water production is directly associated to reservoir, by conning, channeling and/or fingering, generally associated to mobility difference between water and oil, the nowadays most efficient treatment is the injection of relative permeability modifier. This paper will present techniques and results obtained with matrix injection in some fields by the use of the last generation of RPM (relative permeability modifier). (author)

  18. Correlação entre permeabilidade e resistência mecânica de filtros cerâmicos no sistema Al2O3-SiC Relationship between permeability and mechanical strength of Al2O3-SiC ceramic filters

    Directory of Open Access Journals (Sweden)

    V. R. Salvini

    2000-06-01

    Full Text Available Tem sido crescente o uso de cerâmicas reticulares em processos de refino e purificação de metais fundidos, filtração de gases quentes e combustão catalítica. A aplicação depende da composição química e das propriedades físicas do material (número de poros por polegada linear (ppi, porosidade e diâmetro de poro. Há um consenso de que a melhoria das propriedades dos filamentos resulta em um melhor desempenho mecânico do filtro cerâmico. Entretanto, a análise dos valores de resistência mecânica não pode ser considerada isoladamente, uma vez que para filtros cerâmicos esta tem que estar associada à permeabilidade. Neste trabalho é feita uma análise entre as propriedades fluidodinâmicas e mecânicas de filtros cerâmicos no sistema Al2O3-SiC na faixa de 8 a 90 ppi. Os resultados obtidos permitem considerações tanto no aspecto do processamento cerâmico quanto no modelamento mecânico apresentado na literatura.Reticulate ceramics have been increasingly employed in purification of gases, liquid metals and in catalytic processes. The application area usually depends on the chemical composition and the physical properties (porosity, pore size and pore counting (ppi. In most cases, reticulate ceramics are submitted to compression loads at high temperatures, which makes the durability of these cellular materials be ultimately related to the mechanical quality of the struts. In filtration applications, it is also important the evaluation of fluid dynamic properties of the ceramic, specifically its permeability to fluid flow. In this work, a relationship between mechanical properties and permeability constants of Al2O3-SiC ceramic foam filters with 8 to 90 ppi is presented. Results were associated with the processing technique and with the mechanical modeling presented in the literature.

  19. Cross-Cultural Differences in the Experience of Grandparent-Grandchild Relationships and Related Psychosocial Outcomes.

    Science.gov (United States)

    Hayslip, Bert; Toledo, Ray M; Henderson, Craig E; Rodriguez, R Mishelle; Caballero Vela, Daniela M

    2018-01-01

    This study examined grandchildren's perceptions of the quality of their relationship with their grandmothers and how these perceptions relate to psychosocial outcomes. Eighty-two youth from Mexico and 99 youth from the United States aged between 13 and 16 participated. Results suggested that both cultures benefit in unique ways from positive relationship with their grandmothers. Yet, there were also differences in the relational experience of grandmother-grandchild relationships across cultures. Specifically, grandchildren in the U.S. sample reported higher relationship quality, relational competency, and self-efficacy than the grandchildren in the Mexico sample. Within the U.S. sample, relationship quality was associated with grandchildren's relational competence, while in the Mexico sample, relationship quality was associated with self-efficacy. Limitations of the present study include restricted generalizability to other age groups and to grandfathers and that only one element of the grandparent-grandchild dyad was sampled. Longitudinal research will improve our understanding of the causal dynamics of grandparent-grandchild relationships.

  20. The Relationship Between Job Satisfaction and Productivity-Related Costs: A Longitudinal Analysis.

    Science.gov (United States)

    Arnold, Amélie E; Coffeng, Jennifer K; Boot, Cécile R L; van der Beek, Allard J; van Tulder, Maurits W; Nieboer, Dagmar; van Dongen, Johanna M

    2016-09-01

    The aim of this study was to examine the longitudinal relationship between job satisfaction and total productivity-related costs, and between job satisfaction and absenteeism and presenteeism costs separately. A secondary aim was to explore whether these relationships differed across job types. Linear generalized estimating equation analyses were used to explore the longitudinal relationships. To explore whether the relationships differed across job types, stratified analyses were performed. A significant relationship was found between job satisfaction and total productivity-related costs [β = &OV0556;-273; 95% confidence interval (95% CI): -407 to -200] and between job satisfaction and presenteeism costs (β = &OV0556;-276; 95% CI: -367 to -235), but not between job satisfaction and absenteeism costs. These relationships differed across job types. Higher levels of job satisfaction were longitudinally related to lower total productivity-related costs and presenteeism costs, but not to lower absenteeism costs. These relationships seem to differ across job types.

  1. A Reconciliation of Packed Column Permeability Data: Column Permeability as a Function of Particle Porosity

    Directory of Open Access Journals (Sweden)

    Hubert M. Quinn

    2014-01-01

    Full Text Available In his textbook teaching of packed bed permeability, Georges Guiochon uses mobile phase velocity as the fluid velocity term in his elaboration of the Darcy permeability equation. Although this velocity frame makes a lot of sense from a thermodynamic point of view, it is valid only with respect to permeability at a single theoretical boundary condition. In his more recent writings, however, Guiochon has departed from his long-standing mode of discussing permeability in terms of the Darcy equation and has embraced the well-known Kozeny-Blake equation. In this paper, his teaching pertaining to the constant in the Kozeny-Blake equation is examined and, as a result, a new correlation coefficient is identified and defined herein based on the velocity frame used in his teaching. This coefficient correlates pressure drop and fluid velocity as a function of particle porosity. We show that in their experimental protocols, Guiochon et al. have not adhered to a strict material balance of permeability which creates a mismatch of particle porosity and leads to erroneous conclusions regarding the value of the permeability coefficient in the Kozeny-Blake equation. By correcting the experimental data to properly reflect particle porosity we reconcile the experimental results of Guiochon and Giddings, resulting in a permeability reference chart which is presented here for the first time. This reference chart demonstrates that Guiochon’s experimental data, when properly normalized for particle porosity and other related discrepancies, corroborates the value of 267 for the constant in the Kozeny-Blake equation which was derived by Giddings in 1965.

  2. Prediction of Hydrocarbon Reservoirs Permeability Using Support Vector Machine

    Directory of Open Access Journals (Sweden)

    R. Gholami

    2012-01-01

    Full Text Available Permeability is a key parameter associated with the characterization of any hydrocarbon reservoir. In fact, it is not possible to have accurate solutions to many petroleum engineering problems without having accurate permeability value. The conventional methods for permeability determination are core analysis and well test techniques. These methods are very expensive and time consuming. Therefore, attempts have usually been carried out to use artificial neural network for identification of the relationship between the well log data and core permeability. In this way, recent works on artificial intelligence techniques have led to introduce a robust machine learning methodology called support vector machine. This paper aims to utilize the SVM for predicting the permeability of three gas wells in the Southern Pars field. Obtained results of SVM showed that the correlation coefficient between core and predicted permeability is 0.97 for testing dataset. Comparing the result of SVM with that of a general regression neural network (GRNN revealed that the SVM approach is faster and more accurate than the GRNN in prediction of hydrocarbon reservoirs permeability.

  3. A theoretical model for gas permeability in a composite membrane

    International Nuclear Information System (INIS)

    Serrano, D. A

    2009-01-01

    We present in this work an analytical expression for permeability in a two-layer composite membrane, which was derived assuming the same hypothesis as those of Adzumi model for permeability in a homogeneous membrane. Whereas in Adzumi model permeability shows a linear dependence on the mean pressure, our model for a composite membrane related permeability to pressure through a rather complex expression, which covers the whole range of flow, from molecular-Knudsen to viscous-Poiseuille regimes. The expression obtained for permeability contained information of membrane structural properties as pore size, porosity and thickness of each layer, as well as gas nature and operational conditions. Our two-layer-model expression turns into Adzumi formula when the structure of the layers approach to each other. [es

  4. Relational aggression and victimization in gay male relationships: the role of internalized homophobia.

    Science.gov (United States)

    Kelley, Thomas M; Robertson, Richard A

    2008-01-01

    This article presents two studies that are the first to examine relational aggression and relational victimization in gay male peer relationships. A qualitative pilot study provides a strong rationale for a subsequent empirical investigation of 100 young adult, self-identified gay males. Results of both studies demonstrate that relational aggression and relational victimization are common experiences in gay male relationships. They also reveal forms of relational aggression and victimization that appear to be unique to gay males (e.g., outing). Results of the empirical study found significant relations between engaging in relational aggression against gay males and experiencing relational victimization and between experiencing relational victimization and internalized homophobia. However, there was no significant correlation between internalized homophobia and engaging in relational aggression. A multiple regression analysis found that experiencing relational victimization was correlated more strongly with the combination of engaging in relational aggression and internalized homophobia together than with relational aggression alone. Results are discussed within the framework of Allport's "traits due to victimization" theory and Meyer's theory of "minority stress." Implications for the prevention of relational aggression/victimization in gay male relationships are offered. Copyright 2008 Wiley-Liss, Inc.

  5. Unsaturated and Saturated Permeabilities of Fiber Reinforcement: Critics and Suggestions

    Directory of Open Access Journals (Sweden)

    Chung Hae ePARK

    2015-04-01

    Full Text Available In general, permeability measurement results show a strong scattering according to the measurement method, the type of test fluid and the fluid injection condition, even though permeability is regarded as a unique property of porous medium. In particular, the discrepancy between the unsaturated and saturated permeabilities for the same fabric has been widely reported. In the literature, relative permeability has been adopted to model the unsaturated flow. This approach has some limits in the modeling of double-scale porosity medium. We address this issue of permeability measurement by rigorously examining the mass conservation condition. Finally, we identify that the pressure gradient is non-linear with positive curvature in the unsaturated flow and a misinterpretation of pressure gradient is the main reason for the difference between the saturated and unsaturated permeabilities of the same fiber reinforcement. We propose to use a fixed value of permeability and to modify the mass conservation equation if there are air voids which are entrapped inside the fiber tow. Finally, we also suggest some guidelines and future perspectives to obtain more consistent permeability measurement results.

  6. Permeability testing of biomaterial membranes

    Energy Technology Data Exchange (ETDEWEB)

    Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B [NMI Natural and Medical Sciences Institute at University Tuebingen, Markwiesenstr. 55, D-72770 Reutlingen (Germany); Ahlers, M [GELITA AG, Gammelsbacher Str. 2, D-69412 Eberbach (Germany)], E-mail: schlosshauer@nmi.de

    2008-09-01

    The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation.

  7. Permeability testing of biomaterial membranes

    International Nuclear Information System (INIS)

    Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B; Ahlers, M

    2008-01-01

    The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation

  8. Exploring the impact of customer relational benefit on relationship commitment in health service sectors.

    Science.gov (United States)

    Weng, Rhay-Hung; Huang, Jin-An; Huang, Ching-Yuan; Huang, Shih-Chang

    2010-01-01

    An increasing number of health service sectors have begun to implement relationship marketing to try to establish long-term relationship with customers. Customer relational benefit has been an important subject for relationship marketing researchers. This study was conducted to investigate how customer relational benefit might influence relationship commitment in health service sectors. The research used a questionnaire survey that retrieved a total number of 403 valid questionnaires. The data were collected by way of personal visits and investigations of outpatients in three regional hospitals in Taiwan. After the reliability and the validity of the questionnaire sample were examined, the data were verified by using hierarchical regression analysis. Results showed that confidence benefit constituted the most pronounced factor for hospital customers. Confidence benefit, social benefit, and special treatment benefit were perceived by customers as the key factors that have a positive influence on relationship commitment. In particular, customers placing greater emphasis on confidence benefit tended to be less willing to establish relationship commitment. When health service managers develop marketing strategies using customer relational benefit, they will still need to enhance customer confidence benefit as one of the main ways of achieving future improvements. In the event where health service managers seek to install resources for establishing and maintaining a good relationship commitment with customers, the crucial factors of social and special treatment benefits should not be ignored when seeking to enhance the customers' perception of confidence benefit.

  9. Mathematical Model to Predict the Permeability of Water Transport in Concrete Structure

    OpenAIRE

    Solomon Ndubuisi Eluozo

    2013-01-01

    Mathematical model to predict the permeability of water transport in concrete has been established, the model is to monitor the rate of water transport in concrete structure. The process of this water transport is based on the constituent in the mixture of concrete. Permeability established a relation on the influence of the micropores on the constituent that made of concrete, the method of concrete placement determine the rate of permeability deposition in concrete structure, permeability es...

  10. ADVANTAGES AND DISADVANTAGES OF MODERN LABORATORY MEASUREMENT OF THE COEFFICIENT OF PERMEABILITY FOR SOIL MATERIALS

    OpenAIRE

    Veinović, Želimir; Kovačević-Zelić, Biljana; Kvasnička, Predrag

    2003-01-01

    Permeability tests are one of the most often performed experiments in geotechnics. Conventional methods conducted by oedometer and triaxial apparatus have many disadvantages, the most significant being the test duration. As a consequence, errors in permeability measurements could occur. On the contrary, by applying modern flow-pump method, permeability measurements can be obtained much more rapidly. Moreover, the permeability/void ratio relation can be obtained by using adequate laboratory de...

  11. The relationship between relational models and individualism and collectivism: evidence from culturally diverse work groups.

    Science.gov (United States)

    Vodosek, Markus

    2009-04-01

    Relational models theory (Fiske, 1991 ) proposes that all thinking about social relationships is based on four elementary mental models: communal sharing, authority ranking, equality matching, and market pricing. Triandis and his colleagues (e.g., Triandis, Kurowski, & Gelfand, 1994 ) have suggested a relationship between the constructs of horizontal and vertical individualism and collectivism and Fiske's relational models. However, no previous research has examined this proposed relationship empirically. The objective of the current study was to test the association between the two frameworks in order to further our understanding of why members of culturally diverse groups may prefer different relational models in interactions with other group members. Findings from this study support a relationship between Triandis' constructs and Fiske's four relational models and uphold Fiske's ( 1991 ) claim that the use of the relational models is culturally dependent. As hypothesized, horizontal collectivism was associated with a preference for equality matching and communal sharing, vertical individualism was related to a preference for authority ranking, and vertical collectivism was related to a preference for authority ranking and communal sharing. However, contrary to expectations, horizontal individualism was not related to a preference for equality matching and market pricing, and vertical individualism was not associated with market pricing. By showing that there is a relationship between Triandis' and Fiske's frameworks, this study closes a gap in relational models theory, namely how culture relates to people's preferences for relational models. Thus, the findings from this study will enable future researchers to explain and predict what relational models are likely to be used in a certain cultural context.

  12. On the Relationships between (Relatively) Advanced Mathematical Knowledge and (Relatively) Advanced Problem-Solving Behaviours

    Science.gov (United States)

    Koichu, Boris

    2010-01-01

    This article discusses an issue of inserting mathematical knowledge within the problem-solving processes. Relatively advanced mathematical knowledge is defined in terms of "three mathematical worlds"; relatively advanced problem-solving behaviours are defined in terms of taxonomies of "proof schemes" and "heuristic behaviours". The relationships…

  13. Fractal Theory for Permeability Prediction, Venezuelan and USA Wells

    Science.gov (United States)

    Aldana, Milagrosa; Altamiranda, Dignorah; Cabrera, Ana

    2014-05-01

    Inferring petrophysical parameters such as permeability, porosity, water saturation, capillary pressure, etc, from the analysis of well logs or other available core data has always been of critical importance in the oil industry. Permeability in particular, which is considered to be a complex parameter, has been inferred using both empirical and theoretical techniques. The main goal of this work is to predict permeability values on different wells using Fractal Theory, based on a method proposed by Pape et al. (1999). This approach uses the relationship between permeability and the geometric form of the pore space of the rock. This method is based on the modified equation of Kozeny-Carman and a fractal pattern, which allows determining permeability as a function of the cementation exponent, porosity and the fractal dimension. Data from wells located in Venezuela and the United States of America are analyzed. Employing data of porosity and permeability obtained from core samples, and applying the Fractal Theory method, we calculated the prediction equations for each well. At the beginning, this was achieved by training with 50% of the data available for each well. Afterwards, these equations were tested inferring over 100% of the data to analyze possible trends in their distribution. This procedure gave excellent results in all the wells in spite of their geographic distance, generating permeability models with the potential to accurately predict permeability logs in the remaining parts of the well for which there are no core samples, using even porority logs. Additionally, empirical models were used to determine permeability and the results were compared with those obtained by applying the fractal method. The results indicated that, although there are empirical equations that give a proper adjustment, the prediction results obtained using fractal theory give a better fit to the core reference data.

  14. Age-related attitudes: the influence on relationships and performance at work

    NARCIS (Netherlands)

    Dr. Franz Josef Gellert; R. Schalk

    2012-01-01

    Purpose: – This paper aims to examine the influence of age and age-related attitudes on relationship factors. In addition, it seeks to assess how both factors affect care service work performance. Design/methodology/approach: – The paper explores the influence of age and age-related attitudes on the

  15. Report on Hydrologic Flow in Low-Permeability Media

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hui-Hai; Birkholzer, Jens

    2013-11-13

    We demonstrate that under normal conditions (under which there are no intersections between tunnels/drifts and conductive geological structures, such as faults), the water flow velocity in the damage zone, as a result of non-Darcian flow behavior, is extremely small such that solute transport is dominated by diffusion, rather than advection. We show that unless non-Darcian flow behavior is considered, significant errors can occur in the “measured” relative-permeability values. We propose a hypothesis to consider the temperature impact based on limited test results from the petroleum literature. To consider the bedding effects, we present an empirical relationship between water flux and hydraulic gradient for non-Darcian water flow in anisotropic cases.

  16. Geothermal Permeability Enhancement - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Joe Beall; Mark Walters

    2009-06-30

    The overall objective is to apply known permeability enhancement techniques to reduce the number of wells needed and demonstrate the applicability of the techniques to other undeveloped or under-developed fields. The Enhanced Geothermal System (EGS) concept presented in this project enhances energy extraction from reduced permeability zones in the super-heated, vapor-dominated Aidlin Field of the The Geysers geothermal reservoir. Numerous geothermal reservoirs worldwide, over a wide temperature range, contain zones of low permeability which limit the development potential and the efficient recovery of heat from these reservoirs. Low permeability results from poorly connected fractures or the lack of fractures. The Enhanced Geothermal System concept presented here expands these technologies by applying and evaluating them in a systematic, integrated program.

  17. MENTAL HEALTH OF ADOLESCENTS IN RELATION TO EMOTIONAL MATURITY AND PARENT CHILD RELATIONSHIP

    OpenAIRE

    Gurmit Singh

    2014-01-01

    The present study was conducted to find the relation of Mental Health of Adolescents with their Emotional Maturity and Parent Child Relationship. The sample comprised of 200 9th class adolescents (100 boys and 100 girls) from Government Secondary Schools of Moga district The data was obtained by using Emotional Maturity Scale (2011) by Singh and Bhargava, Parent Child Relationship Scale (2011) by Rao and Mental Health Battery (2012) by Singh and Gupta. The results of the study showed positive...

  18. Relationship between weight-related behavioral profiles and health outcomes by sexual orientation and gender

    OpenAIRE

    VanKim, Nicole A.; Erickson, Darin J.; Eisenberg, Marla E.; Lust, Katherine; Rosser, B. R. Simon; Laska, Melissa N.

    2016-01-01

    Objective Examine relationships between weight-related factors and weight status, body dissatisfaction, chronic health conditions, and quality of life across sexual orientation and gender. Methods Two- and four-year college students participated in the College Student Health Survey (n=28,703; 2009-2013). Risk differences were calculated to estimate relationships between behavioral profiles and weight status, body satisfaction, diagnosis of a chronic condition, and quality of life, stratified ...

  19. Permeability of cork to gases.

    Science.gov (United States)

    Faria, David P; Fonseca, Ana L; Pereira, Helen; Teodoro, Orlando M N D

    2011-04-27

    The permeability of gases through uncompressed cork was investigated. More than 100 samples were assessed from different plank qualities to provide a picture of the permeability distribution. A novel technique based on a mass spectrometer leak detector was used to directly measure the helium flow through the central area of small disks 10 mm in diameter and 2 mm thick. The permeability for nitrogen, oxygen, and other gases was measured by the pressure rise technique. Boiled and nonboiled cork samples from different sections were evaluated. An asymmetric frequency distribution ranging 3 orders of magnitude (roughly from 1 to 1000 μmol/(cm·atm·day)) for selected samples without macroscopic defects was found, having a peak below 100 μmol/(cm·atm·day). Correlation was found between density and permeability: higher density samples tend to show lower permeability. However, boiled cork showed a mean lower permeability despite having a lower density. The transport mechanism of gases through cork was also examined. Calculations suggest that gases permeate uncompressed cork mainly through small channels between cells under a molecular flow regime. The diameter of such channels was estimated to be in the range of 100 nm, in agreement with the plasmodesmata size in the cork cell walls.

  20. A Study on the Relationship between Public Relations and Brand Strategy

    OpenAIRE

    Xu, Yuanzhong (Victor)

    2005-01-01

    Brand strategy is a useful way to strengthen competitive competence of products. However, the researches on how to implement a successful brand strategy using public relations were rarely found in the existing literature. The main purpose with my dissertation is to investigate the relationship between public relations and brand strategy. In addition, I hope the dissertation can give some suggestions to Chinese companies when they want to implement a brand strategy using public relations. A ...

  1. Quantitative Structure-Activity Relationships and Docking Studies of Calcitonin Gene-Related Peptide Antagonists

    DEFF Research Database (Denmark)

    Jenssen, Håvard; Mehrabian, Mohadeseh; Kyani, Anahita

    2012-01-01

    Defining the role of calcitonin gene-related peptide in migraine pathogenesis could lead to the application of calcitonin gene-related peptide antagonists as novel migraine therapeutics. In this work, quantitative structure-activity relationship modeling of biological activities of a large range...... of calcitonin gene-related peptide antagonists was performed using a panel of physicochemical descriptors. The computational studies evaluated different variable selection techniques and demonstrated shuffling stepwise multiple linear regression to be superior over genetic algorithm-multiple linear regression....... The linear quantitative structure-activity relationship model revealed better statistical parameters of cross-validation in comparison with the non-linear support vector regression technique. Implementing only five peptide descriptors into this linear quantitative structure-activity relationship model...

  2. An assessment of the relationships between overweight, obesity, related chronic health conditions and worker absenteeism.

    Science.gov (United States)

    Howard, Jeffrey T; Potter, Lloyd B

    2014-01-01

    Worker absenteeism is an important area of study within the field of occupational health. Prior studies have linked the presence of obesity to higher rates of absenteeism, but have not examined whether or not the relationship is moderated by the presence of other chronic health conditions or whether or not the relationships have been stable over time. Data from the 2000 and 2010 National Health Interview Survey, a nationally representative sample of the US population, were analyzed to determine the extent to which the presence of 5 obesity-related chronic health conditions moderates the relationship between overweight/obesity and worker absenteeism, and whether or not these relationships are stable over time. Logistic regression was used to examine the relationships between overweight/obesity, the obesity-related chronic health conditions and worker absenteeism, while controlling for demographic, socio-economic, occupational, health related and behavioral variables. The findings suggest that obesity (p absenteeism, and that the effect is doubled for those with both class III obesity (BMI ≥ 40) and diabetes. The moderating effect between class III obesity and diabetes was observed only in 2010, indicating that this may be a relatively new phenomenon. © 2014 Asian Oceanian Association for the Study of Obesity . Published by Elsevier Ltd. All rights reserved.

  3. Effect of confining pressure on permeability behavior of Beishan granite

    International Nuclear Information System (INIS)

    Ma Like; Li Yunfeng; Zhao Xingguang; Tan Guohuan

    2012-01-01

    By using of the Electro-Hydraulic Servo-controlled Rock Mechanics Testing System (MTS 815.04) in the University of Hong Kong, a series of permeability tests were performed on specimens of Beishan granite at different confining pressures. The result indicates that: (1) there is a decrease of permeability due to progressive closure of initial microcracks and the corresponding volumetric strain is compressive when the confining pressures increase from 2.5 MPa to 15 MPa, (2) when the confining pressures decrease from 15 MPa to 2.5 MPa, there is an increase of permeability in this stage in relation with the volumetric dilation. (authors)

  4. Has the American Public's Interest in Information Related to Relationships Beyond "The Couple" Increased Over Time?

    Science.gov (United States)

    Moors, Amy C

    2017-01-01

    Finding romance, love, and sexual intimacy is a central part of our life experience. Although people engage in romance in a variety of ways, alternatives to "the couple" are largely overlooked in relationship research. Scholars and the media have recently argued that the rules of romance are changing, suggesting that interest in consensual departures from monogamy may become popular as people navigate their long-term coupling. This study utilizes Google Trends to assess Americans' interest in seeking out information related to consensual nonmonogamous relationships across a 10-year period (2006-2015). Using anonymous Web queries from hundreds of thousands of Google search engine users, results show that searches for words related to polyamory and open relationships (but not swinging) have significantly increased over time. Moreover, the magnitude of the correlation between consensual nonmonogamy Web queries and time was significantly higher than popular Web queries over the same time period, indicating this pattern of increased interest in polyamory and open relationships is unique. Future research avenues for incorporating consensual nonmonogamous relationships into relationship science are discussed.

  5. Relationship Power, Sociodemographics, and Their Relative Influence on Sexual Agreements Among Gay Male Couples.

    Science.gov (United States)

    Perry, Nicholas S; Huebner, David M; Baucom, Brian R; Hoff, Colleen C

    2016-06-01

    Men who have sex with men (MSM) in primary relationships engage in condomless sex both within and outside their relationships and a majority of HIV transmission risk may actually occur within primary relationships. Sexual agreements regarding non-monogamy are a critical component to understanding HIV prevention in male couples. Relationship factors have been associated with how sexual agreements function and power is one dyadic construct likely to affect couple's maintenance of non-monogamy agreements. Multilevel modeling was used in a cross-sectional study of gay male couples (N = 566 couples) to examine associations between partners' demographic characteristics traditionally used to define relationship power, a scale of decision-making power, and outcomes related to sexual agreements, including investment, agreement breaks, and break disclosure. Results indicated that decision-making power relative to one's partner was not associated with any agreement outcome, contrary to hypotheses. However, controlling for decision-making power, demographic bases of power were variably associated with sexual agreements' functioning. Younger partners were less invested in and more frequently broke their agreements. Lower-earning partners broke their agreements more frequently, but also disclosed breaks more often. White men in white-minority relationships broke their agreement more often than their partners. Concordant HIV-positive couples were less invested in their agreements and HIV-positive men disclosed breaks more frequently. HIV prevention efforts for same-sex couples must attend to the social, developmental, and cultural influences that affect their agreements around non-monogamy.

  6. Job-Related Circular Mobility and the Quality of Intimate Relationships

    Directory of Open Access Journals (Sweden)

    Michael Feldhaus

    2013-06-01

    Full Text Available This paper addresses the influence of different types of spatial mobility on relationship quality. Although some studies have been carried out on this question, the existing empirical results remain contradictory. The paper tries to overcome some of these limitations by analysing to what extent mobility demands show direct as well as indirect effects. Spatial mobility could have impacts on crucial aspects of relationship dynamics, which are theoretically and empirically identified as significant for relationship satisfaction. The mediating variables used therefore include relatedness, autonomy, conflict and the perceived fairness with regard to the division of labour. The data support the stress hypothesis which assumes that job-related mobility has a negative effect on the relationship quality, but only for women and mothers. There are actually positive effects for men. In terms of indirect effects, the results show that spatial mobility does neither reduce relatedness in relationships nor increase conflict behaviour significantly. In fact, the opposite effect seems to come to play: There is empirical evidence, especially for women, that more demanding mobility increases the feeling of autonomy within a relationship. It also increases relatedness and reduces perceived conflicts, this in turn having a positive effect on relationship quality.

  7. Characterization and estimation of permeability correlation structure from performance data

    Energy Technology Data Exchange (ETDEWEB)

    Ershaghi, I.; Al-Qahtani, M. [Univ. of Southern California, Los Angeles, CA (United States)

    1997-08-01

    In this study, the influence of permeability structure and correlation length on the system effective permeability and recovery factors of 2-D cross-sectional reservoir models, under waterflood, is investigated. Reservoirs with identical statistical representation of permeability attributes are shown to exhibit different system effective permeability and production characteristics which can be expressed by a mean and variance. The mean and variance are shown to be significantly influenced by the correlation length. Detailed quantification of the influence of horizontal and vertical correlation lengths for different permeability distributions is presented. The effect of capillary pressure, P{sub c1} on the production characteristics and saturation profiles at different correlation lengths is also investigated. It is observed that neglecting P{sub c} causes considerable error at large horizontal and short vertical correlation lengths. The effect of using constant as opposed to variable relative permeability attributes is also investigated at different correlation lengths. Next we studied the influence of correlation anisotropy in 2-D reservoir models. For a reservoir under five-spot waterflood pattern, it is shown that the ratios of breakthrough times and recovery factors of the wells in each direction of correlation are greatly influenced by the degree of anisotropy. In fully developed fields, performance data can aid in the recognition of reservoir anisotropy. Finally, a procedure for estimating the spatial correlation length from performance data is presented. Both the production performance data and the system`s effective permeability are required in estimating the correlation length.

  8. Exploring factors related to college student expertise in digital games and their relationships to academics

    Directory of Open Access Journals (Sweden)

    Hamlen Karla R.

    2017-06-01

    Full Text Available Digital game play is a common pastime among college students and monopolizes a great deal of time for many students. Researchers have previously investigated relationships between subject-specific game play and academics, but this study fulfills a need for research focusing on entertainment game strategies and how they relate to strategies and success in other contexts. Utilizing a survey of 191 undergraduate students, the goal was to investigate students’ digital game play habits, strategies, and beliefs that predict gaming expertise, and to determine if these relate to academic success. Factor analysis revealed three latent variables that predict expertise: dedication, solo mastery, and strategic play. Multiple regression analysis was used to determine whether these three components could also predict academic outcome variables. Findings point to the absence of a relationship between these variables and academic GPA, but to the presence of a tentative relationship between confidence in game play and confidence in personal control over academic success.

  9. Gender differences in associations between cancer-related problems and relationship dissolution among cancer survivors.

    Science.gov (United States)

    Stephens, Cristina; Westmaas, J Lee; Kim, Jihye; Cannady, Rachel; Stein, Kevin

    2016-10-01

    Research suggests that a cancer diagnosis predicts marital dissolution more strongly for women survivors than men, but there is a paucity of research on potential processes underlying this vulnerability. The present cross-sectional study examined whether specific cancer-related problems were associated with the odds of relationship breakup following diagnosis and whether these relationships differed between male and female cancer survivors. A national cross-sectional quality of life study assessed self-reported cancer-related problems and relationship change among survivors who were either 2, 6, or 10 years post-diagnosis (n = 6099). Bivariate analyses indicated that cancer-related problems (e.g., emotional distress) were greater for divorced/separated survivors compared to those with intact relationships and were greater for women versus men. Logistic regressions indicated that for both male and female survivors, lower income, younger age, and longer time since diagnosis were associated with greater odds of divorce or separation after diagnosis (ORs > 2.14, p emotional distress (OR = 1.14, p divorce or separation. For men only, fear of cancer recurrence was associated with greater odds of divorce or separation (OR = 1.32, p emotional or financial/employment problems attributed to the cancer diagnosis were associated with the likelihood of reporting relationship dissolution. Although directions of causality could not be ascertained, results suggest the possibility that helping male and female cancer survivors cope with specific cancer-related problems may benefit the quality and stability of their relationships with significant others following diagnosis.

  10. Bentonite Permeability at Elevated Temperature

    Directory of Open Access Journals (Sweden)

    Katherine A. Daniels

    2017-01-01

    Full Text Available Repository designs frequently favour geological disposal of radioactive waste with a backfill material occupying void space around the waste. The backfill material must tolerate the high temperatures produced by decaying radioactive waste to prevent its failure or degradation, leading to increased hydraulic conductivity and reduced sealing performance. The results of four experiments investigating the effect of temperature on the permeability of a bentonite backfill are presented. Bentonite is a clay commonly proposed as the backfill in repository designs because of its high swelling capacity and very low permeability. The experiments were conducted in two sets of purpose-built, temperature controlled apparatus, designed to simulate isotropic pressure and constant volume conditions within the testing range of 4–6 MPa average effective stress. The response of bentonite during thermal loading at temperatures up to 200 °C was investigated, extending the previously considered temperature range. The results provide details of bentonite’s intrinsic permeability, total stress, swelling pressure and porewater pressure during thermal cycles. We find that bentonite’s hydraulic properties are sensitive to thermal loading and the type of imposed boundary condition. However, the permeability change is not large and can mostly be accounted for by water viscosity changes. Thus, under 150 °C, temperature has a minimal impact on bentonite’s hydraulic permeability.

  11. Relationship on the Relational Benefit Effect of Oil Products on Customer Satisfaction

    Directory of Open Access Journals (Sweden)

    Jing Muxue

    2017-01-01

    Full Text Available In order to find out the relationship of relational benefit effect of oil products on customer satisfaction, the local fractional algorithm is proposed in this paper for data analysis. It is investigated the adjustment effect of alternative brand competitiveness and customer characteristics to this mechanism. The results show that the proposed algorithm can thus improve overall system performance substantially.

  12. A Feminist Posthumanist Political Ecology of Education for Theorizing Human-Animal Relations/Relationships

    Science.gov (United States)

    Lloro-Bidart, Teresa

    2017-01-01

    This paper contributes to a nascent conversation in environmental education (EE) research by using ethnographic data and extant theory to develop a feminist posthumanist political ecology of education for theorizing human-animal relations/relationships. Specifically, I (1) engage feminist methodologies and theories; (2) give epistemological and…

  13. Relationships among Shyness, Social Competence, Peer Relations, and Theory of Mind among Pre-Adolescents

    Science.gov (United States)

    Kokkinos, Constantinos M.; Kakarani, Styliani; Kolovou, Demetra

    2016-01-01

    The present study examined the relationships between shyness, a number of personal and interpersonal variables (i.e. social skills, self-esteem, attachment style, advanced Theory of Mind skills and peer relations) in a sample of 243 Greek pre-adolescents. Participants completed self-reports of the variables. Results indicated that females scored…

  14. The determinants of relational governance and performance: how to manage business relationships?

    NARCIS (Netherlands)

    Claro, D.P.; Hagelaar, J.L.F.; Omta, S.W.F.

    2003-01-01

    It is the aim of this study to assess the influence of the determinants of the transaction, dyadic, and business environment level on relational governance and ultimately performance. We build an integrated framework for relationship management drawing from literature of transaction cost economics,

  15. On the relationships among work characteristics and learning-related behavior : Does age matter?

    NARCIS (Netherlands)

    De Lange, Annet H.; Taris, Toon W.; Jansen, Paul; Kompier, Michiel A. J.; Houtman, Irene L. D.; Bongers, Paulien M.

    2010-01-01

    This 3-wave longitudinal study examined (a) the causal direction of the relationships among psychosocial work characteristics (e.g., job demands, job control, and supervisor support) and indicators of learning-related behavior (e.g., motivation to learn and active problem solving), and (b) whether

  16. Theory and test research on permeability of coal and rock body influenced by mining

    Energy Technology Data Exchange (ETDEWEB)

    Qing-xin Qi; Hong-yan Li; You-gang Wang; Zhi-gang Deng; Hang Lan; Yong-wei Peng; Chun-rui Li [China Coal Research Institute, Beijing (China)

    2009-06-15

    Stress distribution rules and deformation and failure properties of coal and rock bodies influenced by mining were analyzed. Experimental research on permeability of coal and rock samples under different loading conditions was finished in the laboratory. In-situ measurement of coal permeability influenced by actual mining was done as well. Theory analysis show that permeability varied with damage development of coal and rock under stress, and the influence of fissure on permeability was greatest. Laboratory results show that under different loading conditions permeability was different and it varied with stress, which indicated that permeability was directly related to the loading process. In-situ tests showed that permeability is related to abutment stress to some degree. The above results may be referenced to gas prevention and drainage. 11 refs., 6 figs., 1 tab.

  17. Relationship between Income and Subjective Economic Well-Being: Absolute or Relative?

    Directory of Open Access Journals (Sweden)

    V A Khashchenko

    2012-09-01

    Full Text Available The article considers the role of the absolute and relative income in determining the subjective economic well-being. It is shown that the relationship of the income to SEB is curvilinear with the increase of marginal utility for a higher income. At low income levels its effect on SEB is determined not by its absolute, but by its relative value based on the comparisons with the subjective standards of well-being.

  18. Ambulance Work : Relationships between occupational demands, individual characteristics and health-related outcomes

    OpenAIRE

    Aasa, Ulrika

    2005-01-01

    Although musculoskeletal disorders (MSDs) and other health complaints are an occupational problem for ambulance personnel, there is a lack of knowledge regarding work-related factors associated with MSDs and other health complaints. The overall aim of this thesis was to investigate the relationships between occupational demands, individual characteristics and health-related outcomes among ambulance personnel. A random sample of 234 female and 953 male ambulance personnel participated in a nat...

  19. A Non-linear "Inflation-Relative Prices Variability" Relationship: Evidence from Latin America

    OpenAIRE

    Mª Ángeles Caraballo Pou; Carlos Dabús; Diego Caramuta

    2006-01-01

    This paper presents evidence on a non-linear "inflation-relative prices variability" relationship in three Latin American countries with very high inflation experiences: Argentina, Brazil and Peru. More precisely, and in contrast to results found in previous literature for similar countries, we find a non-concave relation at higher inflation regimes, i.e. when inflation rate surpasses certain threshold. This non-concavity is mainly explained by the unexpected component of inflation, which sug...

  20. An integrated approach to permeability modeling using micro-models

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, A.H.; Leuangthong, O.; Deutsch, C.V. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Alberta Univ., Edmonton, AB (Canada)

    2008-10-15

    An important factor in predicting the performance of steam assisted gravity drainage (SAGD) well pairs is the spatial distribution of permeability. Complications that make the inference of a reliable porosity-permeability relationship impossible include the presence of short-scale variability in sand/shale sequences; preferential sampling of core data; and uncertainty in upscaling parameters. Micro-modelling is a simple and effective method for overcoming these complications. This paper proposed a micro-modeling approach to account for sampling bias, small laminated features with high permeability contrast, and uncertainty in upscaling parameters. The paper described the steps and challenges of micro-modeling and discussed the construction of binary mixture geo-blocks; flow simulation and upscaling; extended power law formalism (EPLF); and the application of micro-modeling and EPLF. An extended power-law formalism to account for changes in clean sand permeability as a function of macroscopic shale content was also proposed and tested against flow simulation results. There was close agreement between the model and simulation results. The proposed methodology was also applied to build the porosity-permeability relationship for laminated and brecciated facies of McMurray oil sands. Experimental data was in good agreement with the experimental data. 8 refs., 17 figs.

  1. Media depictions of physical and relational aggression: connections with aggression in young adults' romantic relationships.

    Science.gov (United States)

    Coyne, Sarah M; Nelson, David A; Graham-Kevan, Nicola; Tew, Emily; Meng, K Nathan; Olsen, Joseph A

    2011-01-01

    Various studies have found that viewing physical or relational aggression in the media can impact subsequent engagement in aggressive behavior. However, this has rarely been examined in the context of relationships. Accordingly, the aim of this study was to examine the connection between viewing various types of aggression in the media and perpetration of aggression against a romantic partner. A total of 369 young adults completed a variety of questionnaires asking for their perpetration of various forms of relationship aggression. Participants' exposure to both physical and relational aggression in the media was also assessed. As a whole, we found a relationship between viewing aggression in the media and perpetration of aggression; however, this depended on the sex of the participant and the type of aggression measured. Specifically, exposure to physical violence in the media was related to engagement in physical aggression against their partner only for men. However, exposure to relational aggression in the media was related to romantic relational aggression for both men and women.

  2. Three-dimensional analysis of relationship between relative orientation and motion modes

    Directory of Open Access Journals (Sweden)

    Fan Shijie

    2014-12-01

    Full Text Available Target motion modes have a close relationship with the relative orientation of missile-to-target in three-dimensional highly maneuvering target interception. From the perspective of relationship between the sensor coordinate system and the target body coordinate system, a basic model of sensor is stated and the definition of relative angular velocity between the two coordinate systems is introduced firstly. Then, the three-dimensional analytic expressions of relative angular velocity for different motion modes are derived and simplified by analyzing the influences of target centroid motion, rotation around centroid and relative motion. Finally, the relationships of the relative angular velocity directions and values with motion modes are discussed. Simulation results validate the rationality of the theoretical analysis. It is demonstrated that there are significant differences of the relative orientation in different motion modes which include luxuriant information about motion modes. The conclusions are significant for the research of motion mode identification, maneuver detection, maneuvering target tracking and interception using target signatures.

  3. Cancer-related communication, relationship intimacy, and psychological distress among couples coping with localized prostate cancer.

    Science.gov (United States)

    Manne, Sharon; Badr, Hoda; Zaider, Talia; Nelson, Christian; Kissane, David

    2010-03-01

    The present study evaluated intimacy as a mechanism for the effects of relationship-enhancing (self-disclosure, mutual constructive communication) and relationship-compromising communication (holding back, mutual avoidance, and demand-withdraw communication) on couples' psychological distress. Seventy-five men diagnosed with localized prostate cancer in the past year and their partners completed surveys about communication, intimacy, and distress. Multi-level models with the couple as unit of analyses indicated that the association between mutual constructive communication, mutual avoidance, and patient demand-partner withdraw and distress could be accounted for by their influence on relationship intimacy. Intimacy did not mediate associations between self-disclosure, holding back, and partner demand-patient withdraw communication and distress. These findings indicate that the way in which couples talk about cancer-related concerns as well as the degree to which one or both partners avoid talking about cancer-related concerns can either facilitate or reduce relationship intimacy, and that it is largely by this mechanism that these three communication strategies impact psychological distress. Relationship intimacy and how patients and partners communicate to achieve this intimacy is important for the psychological adjustment of early stage prostate cancer survivors and their partners.

  4. Relationships between nutrient-related plant traits and combinations of soil N and P fertility measures.

    Science.gov (United States)

    Fujita, Yuki; van Bodegom, Peter M; Witte, Jan-Philip M

    2013-01-01

    Soil fertility and nutrient-related plant functional traits are in general only moderately related, hindering the progress in trait-based prediction models of vegetation patterns. Although the relationships may have been obscured by suboptimal choices in how soil fertility is expressed, there has never been a systematic investigation into the suitability of fertility measures. This study, therefore, examined the effect of different soil fertility measures on the strength of fertility-trait relationships in 134 natural plant communities. In particular, for eight plot-mean traits we examined (1) whether different elements (N or P) have contrasting or shared influences, (2) which timescale of fertility measures (e.g. mineralization rates for one or five years) has better predictive power, and (3) if integrated fertility measures explain trait variation better than individual fertility measures. Soil N and P had large mutual effects on leaf nutrient concentrations, whereas they had element-specific effects on traits related to species composition (e.g. Grime's CSR strategy). The timescale of fertility measures only had a minor impact on fertility-trait relationships. Two integrated fertility measures (one reflecting overall fertility, another relative availability of soil N and P) were related significantly to most plant traits, but were not better in explaining trait variation than individual fertility measures. Using all fertility measures together, between-site variations of plant traits were explained only moderately for some traits (e.g. 33% for leaf N concentrations) but largely for others (e.g. 66% for whole-canopy P concentration). The moderate relationships were probably due to complex regulation mechanisms of fertility on traits, rather than to a wrong choice of fertility measures. We identified both mutual (i.e. shared) and divergent (i.e. element-specific and stoichiometric) effects of soil N and P on traits, implying the importance of explicitly

  5. Modelling the permeability of polymers: a neural network approach

    NARCIS (Netherlands)

    Wessling, Matthias; Mulder, M.H.V.; Bos, A.; Bos, A.; van der Linden, M.K.T.; Bos, M.; van der Linden, W.E.

    1994-01-01

    In this short communication, the prediction of the permeability of carbon dioxide through different polymers using a neural network is studied. A neural network is a numeric-mathematical construction that can model complex non-linear relationships. Here it is used to correlate the IR spectrum of a

  6. Social relationships and health: the relative roles of family functioning and social support.

    Science.gov (United States)

    Franks, P; Campbell, T L; Shields, C G

    1992-04-01

    The associations between social relationships and health have been examined using two major research traditions. Using a social epidemiological approach, much research has shown the beneficial effect of social supports on health and health behaviors. Family interaction research, which has grown out of a more clinical tradition, has shown the complex effects of family functioning on health, particularly mental health. No studies have examined the relative power of these two approaches in explicating the connections between social relationships and health. We hypothesized that social relationships (social support and family functioning) would exert direct and indirect (through depressive symptoms) effects on health behaviors. We also hypothesized that the effects of social relationships on health would be more powerfully explicated by family functioning than by social support. We mailed a pilot survey to a random sample of patients attending a family practice center, including questions on depressive symptoms, cardiovascular health behaviors, demographics, social support using the ISEL scale, and family functioning using the FEICS scale. FEICS is a self-report questionnaire designed to assess family emotional involvement and criticism, the media elements of family expressed emotion. Eighty-three useable responses were obtained. Regression analyses and structural modelling showed both direct and indirect statistically significant paths from social relationships to health behaviors. Family criticism was directly associated (standardized coefficient = 0.29) with depressive symptoms, and family emotional involvement was directly associated with both depressive symptoms (coefficient = 0.35) and healthy cardiovascular behaviors (coefficient = 0.32). The results support the primacy of family functioning factors in understanding the associations among social relationships, mental health, and health behaviors. The contrasting relationships between emotional involvement and

  7. Permeability enhancement by shock cooling

    Science.gov (United States)

    Griffiths, Luke; Heap, Michael; Reuschlé, Thierry; Baud, Patrick; Schmittbuhl, Jean

    2015-04-01

    The permeability of an efficient reservoir, e.g. a geothermal reservoir, should be sufficient to permit the circulation of fluids. Generally speaking, permeability decreases over the life cycle of the geothermal system. As a result, is usually necessary to artificially maintain and enhance the natural permeability of these systems. One of the methods of enhancement -- studied here -- is thermal stimulation (injecting cold water at low pressure). This goal of this method is to encourage new thermal cracks within the reservoir host rocks, thereby increasing reservoir permeability. To investigate the development of thermal microcracking in the laboratory we selected two granites: a fine-grained (Garibaldi Grey granite, grain size = 0.5 mm) and a course-grained granite (Lanhelin granite, grain size = 2 mm). Both granites have an initial porosity of about 1%. Our samples were heated to a range of temperatures (100-1000 °C) and were either cooled slowly (1 °C/min) or shock cooled (100 °C/s). A systematic microstructural (2D crack area density, using standard stereological techniques, and 3D BET specific surface area measurements) and rock physical property (porosity, P-wave velocity, uniaxial compressive strength, and permeability) analysis was undertaken to understand the influence of slow and shock cooling on our reservoir granites. Microstructurally, we observe that the 2D crack surface area per unit volume and the specific surface area increase as a result of thermal stressing, and, for the same maximum temperature, crack surface area is higher in the shock cooled samples. This observation is echoed by our rock physical property measurements: we see greater changes for the shock cooled samples. We can conclude that shock cooling is an extremely efficient method of generating thermal microcracks and modifying rock physical properties. Our study highlights that thermal treatments are likely to be an efficient method for the "matrix" permeability enhancement of

  8. Relationships between work-related characteristics, needs satisfaction, motivation and mental health in midwifery students.

    Science.gov (United States)

    Ferrand, Claude; Courtois, Robert; Martinent, Guillaume; Rivière, Michèle; Rusch, Emmanuel

    2017-07-01

    The present study examined the relationships between work-related characteristics in internships, psychological needs satisfaction, motivation and mental health using a partial least squares path modeling. Midwifery students (N = 214; M age = 22.8 years) from three French schools completed different questionnaires online. Results showed (1) the importance of work resources (work control and social support) as protective factors of psychological needs satisfaction; and (2) the role of competence need satisfaction through motivation in the relationships between work resources and mental health. Midwifery schools should pay more attention to these two results, and take them into account in midwifery students' training.

  9. Transverse Chemotactic Migration of Bacteria from High to Low Permeability Regions in a Dual Permeability Porous Microfluidic Device

    Science.gov (United States)

    Singh, R.; Olson, M. S.

    2011-12-01

    Low permeability regions sandwiched between high permeability regions such as clay lenses are difficult to treat using conventional treatment methods. Trace concentrations of contaminants such as non-aqueous phase liquids (NAPLs) remain trapped in these regions and over the time diffuse out into surrounding water thereby acting as a long term source of groundwater contamination. Bacterial chemotaxis (directed migration toward a contaminant source), may be helpful in enhancing bioremediation of such contaminated sites. This study is focused on simulating a two-dimensional dual-permeability groundwater contamination scenario using microfluidic devices and evaluating transverse chemotactic migration of bacteria from high to low permeability regions. A novel bi-layer polydimethylsiloxane (PDMS) microfluidic device was fabricated using photolithography and soft lithography techniques to simulate contamination of a dual- permeability region due to leakage from an underground storage tank into a low permeability region. This device consists of a porous channel through which a bacterial suspension (Escherchia Coli HCB33) is flown and another channel for injecting contaminant/chemo-attractant (DL-aspertic acid) into the porous channel. The pore arrangement in the porous channel contains a 2-D low permeability region surrounded by high permeability regions on both sides. Experiments were performed under chemotactic and non-chemotactic (replacing attractant with buffer solution in the non porous channel) conditions. Images were captured in transverse pore throats at cross-sections 4.9, 9.8, and 19.6 mm downstream from the attractant injection point and bacteria were enumerated in the middle of each pore throat. Bacterial chemotaxis was quantified in terms of the change in relative bacterial counts in each pore throat at cross-sections 9.8 and 19.6 mm with respect to counts at the cross-section at 4.9 mm. Under non-chemotactic conditions, relative bacterial count was observed

  10. Contempt and defensiveness in couple relationships related to childhood sexual abuse histories for self and partner.

    Science.gov (United States)

    Walker, Eric C; Sheffield, Rachel; Larson, Jeffry H; Holman, Thomas B

    2011-01-01

    This study examined the relationship between a history of childhood sexual abuse (CSA) for one or both members of a romantic couple and perceptions of contempt and defensiveness for self and partner. Data from the Relationship Evaluation (RELATE) were analyzed for 10,061 couples. The findings suggest that when either or both partner(s) has a history of CSA, contempt and defensiveness in the couple relationship are greater than when neither reports a history of CSA. Furthermore, the males' experience of CSA had a greater impact on their perceptions of self and partner's contempt and defensiveness than females' experience of CSA. Explanations of gender differences are offered and implications for future research and practice are suggested. © 2011 American Association for Marriage and Family Therapy.

  11. Relationship power, decision making, and sexual relations: an exploratory study with couples of Mexican origin.

    Science.gov (United States)

    Harvey, S Marie; Beckman, Linda J; Browner, Carole H; Sherman, Christy A

    2002-11-01

    This study explored how couples of Mexican origin define power in intimate relationships, what makes men and women feel powerful in relationships, and the role of each partner in decision making about sexual and reproductive matters. Interviews were conducted with each partner of 39 sexually active couples and data were analyzed using content analysis. Results indicate that power is perceived as control over one s partner and the ability to make decisions. Women say they feel more powerful in relationships when they make unilateral decisions and have economic independence. Men feel powerful when they have control over their partner and bring home money. Respondents agreed that women make decisions about household matters and children, while men make decisions related to money. Findings indicate that whereas couples share decision making about sexual activities and contraceptive use, men are seen as initiators of sexual activity and women are more likely to suggest condom use.

  12. Observational study of the relationship between entrainment rate and relative dispersion in deep convective clouds

    Science.gov (United States)

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; Liu, Yangang; Zhang, Guang Jun; Luo, Shi

    2018-01-01

    This study investigates the influence of entrainment rate (λ) on relative dispersion (ε) of cloud droplet size distributions (CDSD) in the 99 growing precipitating deep convective clouds during TOGA-COARE. The results show that entrainment suppresses ε, which is opposite to the traditional understanding that entrainment-mixing broadens CDSD. To examine how the relationship between ε and λ is affected by droplets with different sizes, CDSDs are divided into three portions with droplet radius processes is developed to illustrate the possible scenarios entailing different relationships between ε and λ. The number concentration of small droplets and the degree of evaporation of small droplets are found to be key factors that shift the sign (i.e., positive or negative) of the ε-λ relationship.

  13. Analysis of Fault Permeability Using Mapping and Flow Modeling, Hickory Sandstone Aquifer, Central Texas

    Energy Technology Data Exchange (ETDEWEB)

    Nieto Camargo, Jorge E., E-mail: jorge.nietocamargo@aramco.com; Jensen, Jerry L., E-mail: jjensen@ucalgary.ca [University of Calgary, Department of Chemical and Petroleum Engineering (Canada)

    2012-09-15

    Reservoir compartments, typical targets for infill well locations, are commonly created by faults that may reduce permeability. A narrow fault may consist of a complex assemblage of deformation elements that result in spatially variable and anisotropic permeabilities. We report on the permeability structure of a km-scale fault sampled through drilling a faulted siliciclastic aquifer in central Texas. Probe and whole-core permeabilities, serial CAT scans, and textural and structural data from the selected core samples are used to understand permeability structure of fault zones and develop predictive models of fault zone permeability. Using numerical flow simulation, it is possible to predict permeability anisotropy associated with faults and evaluate the effect of individual deformation elements in the overall permeability tensor. We found relationships between the permeability of the host rock and those of the highly deformed (HD) fault-elements according to the fault throw. The lateral continuity and predictable permeability of the HD fault elements enhance capability for estimating the effects of subseismic faulting on fluid flow in low-shale reservoirs.

  14. Breach of belongingness: Newcomer relationship conflict, information, and task-related outcomes during organizational socialization.

    Science.gov (United States)

    Nifadkar, Sushil S; Bauer, Talya N

    2016-01-01

    Previous studies of newcomer socialization have underlined the importance of newcomers' information seeking for their adjustment to the organization, and the conflict literature has consistently reported negative effects of relationship conflict with coworkers. However, to date, no study has examined the consequences of relationship conflict on newcomers' information seeking. In this study, we examined newcomers' reactions when they have relationship conflict with their coworkers, and hence cannot obtain necessary information from them. Drawing upon belongingness theory, we propose a model that moves from breach of belongingness to its proximal and distal consequences, to newcomer information seeking, and then to task-related outcomes. In particular, we propose that second paths exist-first coworker-centric and the other supervisor-centric-that may have simultaneous yet contrasting influence on newcomer adjustment. To test our model, we employ a 3-wave data collection research design with egocentric and Likert-type multisource surveys among a sample of new software engineers and their supervisors working in India. This study contributes to the field by linking the literatures on relationship conflict and newcomer information seeking and suggesting that despite conflict with coworkers, newcomers may succeed in organizations by building relationships with and obtaining information from supervisors. (c) 2016 APA, all rights reserved).

  15. Modification of permeability of frog perineurium to [14C]-sucrose by stretch and hypertonicity

    International Nuclear Information System (INIS)

    Weerasuriya, A.; Rapoport, S.I.; Taylor, R.E.

    1979-01-01

    An in vitro method has been developed to determine quantitatively the permeability of the perineurium to radiotracers at room temperature. The permeability to [ 14 C]sucrose of the isolated perineurium of the sciatic nerve of the frog, Rana pipiens, was measured at rest length, when the perineurium was stretched and after the perineurium had been subjected to hypertonic treatment. Mean permeability at rest length was calculated to be 5.6 +- 0.27 (S.E.M., n=45)x10 -7 cm/sec, and both stretch and hypertonic treatment increased the permeability. A 10% stretch increased permeability reversibly, whereas a 20% stretch or immersion of the perineurium in a hypertonic bath increased permeability irreversibly. Altered permeability under these conditions might be related to changes in the ultrastructure of tight junctions in the perineurium. (Auth.)

  16. Trauma-related guilt: conceptual development and relationship with posttraumatic stress and depressive symptoms.

    Science.gov (United States)

    Browne, Kendall C; Trim, Ryan S; Myers, Ursula S; Norman, Sonya B

    2015-04-01

    Despite high prevalence and concerning associated problems, little effort has been made to conceptualize the construct of posttraumatic guilt. This investigation examined the theoretical model of trauma-related guilt proposed by Kubany and Watson (2003). This model hypothesizes that emotional and physical distress related to trauma memories partially mediates the relationship between guilt cognitions and posttraumatic guilt. Using path analysis, this investigation (a) empirically evaluated relationships hypothesized in Kubany and Watson's model, and (b) extended this conceptualization by evaluating models whereby guilt cognitions, distress, and posttraumatic guilt were related to posttraumatic stress disorder (PTSD) symptoms depression symptom severity. Participants were male U.S. Iraq and Afghanistan veterans (N = 149). Results yielded a significant indirect effect from guilt cognitions to posttraumatic guilt via distress, providing support for Kubany and Watson's model (β = .14). Findings suggested distress may be the strongest correlate of PTSD symptoms (β = .47) and depression symptoms (β = .40), and that guilt cognitions may serve to intensify the relationship between distress and posttraumatic psychopathology. Research is needed to evaluate whether distress specific to guilt cognitions operates differentially on posttraumatic guilt when compared to distress more broadly related to trauma memories. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  17. Establishing the Relationship between Fracture-Related Dolomite and Primary Rock Fabric on the Distribution of Reservoirs in the Michigan Basin

    Energy Technology Data Exchange (ETDEWEB)

    G. Michael Grammer

    2006-09-30

    This topical report covers the year 2 of the subject 3-year grant, evaluating the relationship between fracture-related dolomite and dolomite constrained by primary rock fabric in the 3 most prolific reservoir intervals in the Michigan Basin (Ordovician Trenton-Black River Formations; Silurian Niagara Group; and the Devonian Dundee Formation). The characterization of select dolomite reservoirs has been the major focus of our efforts in Phase II/Year 2. Fields have been prioritized based upon the availability of rock data for interpretation of depositional environments, fracture density and distribution as well as thin section, geochemical, and petrophysical analyses. Structural mapping and log analysis in the Dundee (Devonian) and Trenton/Black River (Ordovician) suggest a close spatial relationship among gross dolomite distribution and regional-scale, wrench fault related NW-SE and NE-SW structural trends. A high temperature origin for much of the dolomite in the 3 studied intervals (based upon initial fluid inclusion homogenization temperatures and stable isotopic analyses,) coupled with persistent association of this dolomite in reservoirs coincident with wrench fault-related features, is strong evidence for these reservoirs being influenced by hydrothermal dolomitization. For the Niagaran (Silurian), a comprehensive high resolution sequence stratigraphic framework has been developed for a pinnacle reef in the northern reef trend where we had 100% core coverage throughout the reef section. Major findings to date are that facies types, when analyzed at a detailed level, have direct links to reservoir porosity and permeability in these dolomites. This pattern is consistent with our original hypothesis of primary facies control on dolomitization and resulting reservoir quality at some level. The identification of distinct and predictable vertical stacking patterns within a hierarchical sequence and cycle framework provides a high degree of confidence at this point

  18. EDZ and permeability in clayey rocks

    International Nuclear Information System (INIS)

    Levasseur, Severine; Collin, Frederic; Charlier, Robert; Besuelle, Pierre; Chambon, Rene; Viggiani, Cino

    2010-01-01

    Document available in extended abstract form only. Deep geological layers are being considered as potential host rocks for the high level radioactivity waste disposals. During drilling in host rocks, an excavated damaged zone - EDZ is created. The fluid transmissivity may be modified in this damaged zone. This paper deals with the permeability evolution in relation with diffuse and/or localized crack propagation in the material. We mainly focus on argillaceous rocks and on some underground laboratories: Mol URL in Boom clay, Bure URL in Callovo-Oxfordian clay and Mont-Terri URL in Opalinus clay. First, observations of damage around galleries are summarized. Structure of damage in localized zone or in fracture has been observed at underground gallery scale within the excavation damaged zone (EDZ). The first challenge for a correct understanding of all the processes occurring within the EDZ is the characterization at the laboratory scale of the damage and localization processes. The observation of the initiation and propagation of the localized zones needs for advanced techniques. X-ray tomography is a non-destructive imaging technique that allows quantification of internal features of an object in 3D. If mechanical loading of a specimen is applied inside a X-ray CT apparatus, successive 3D images at different loading steps show the evolution of the specimen. However, in general volumetric strain in a shear band is small compared to the shear strain and, unfortunately, in tomographic images grey level is mainly sensitive to the local mass density field. Such a limitation has been recently overcome by complementing X-ray tomography with 3D Volumetric Digital Image Correlation (V-DIC) which allows the determination of the full strain tensor field. Then it is possible to further explore the progression of localized deformation in the specimen. The second challenge is the robust modelling of the strain localized process. In fact, modelling the damage process with finite

  19. Relation between dependency and two aspects of self-consciousness : Focusing on dyadic relationships in adolescence

    OpenAIRE

    田宮, 沙紀; 岡本, 祐子

    2013-01-01

    In this study, we focused on dyadic relationships in adolescence and examined the dependent appearance for significant other and the relation with two aspects of the self-consciousness. Two aspects of the self-consciousness are public self-consciousness and private self-consciousness. As a result of factor analysis,it was indicated that adolescents have mature and immature dependencies on significant others and dependent anxiety was observed regardless of the object of dependence. Furthermore...

  20. Relationships between symptomatology and SES-related factors in hyperkinetic/MBD boys.

    Science.gov (United States)

    Paternite, C E; Loney, J; Langhorne, J E

    1976-04-01

    Relationships among symptomatology, socioeconomic status, and parenting styles were examined for 113 hyperkinetic/minimal brain dysfunction boys from intact families. Primary symptoms (e.g. hyperactivity) did not vary as a function of SES, but SES-related differences emerged for secondary symptoms (e.g., aggressive behavior, self-esteem deficits) and for parenting variables. Parenting variables were found to be better predictors of secondary symptoms than was SES. Implications for further research are offered.

  1. The use of technology in relationship management: a public relations perspective.

    OpenAIRE

    2008-01-01

    The statement that the stable and developed world known to us no longer exists seems to be particularly relevant to the way in which organisations conduct their business and reposition themselves in the communication age. Organisations, as the context within which public relations functions, are threatened by increased competition and changes in key elements of market relationships as a result of global information technology developments and the mobility of organisations and people. The emer...

  2. Exchange Rate – Relative Price Nonlinear Cointegration Relationship in Malaysia

    OpenAIRE

    Venus Khim-Sen Liew; Chee-Keong Choong; Evan Lau; Kian-Ping Lim

    2005-01-01

    The finding of exchange rate–relative price nonlinear cointegration relationship in Malaysia, among others, suggests that nonlinear Purchasing Power Parity (PPP) equilibrium may be regarded as reference point in judging the short run misalignment of the Ringgit currency and thereby deducing effective policy actions. Moreover, economists who wish to extend the simple PPP exchange rate model into the more complicated monetary exchange models may do so comfortably, at least in the text of Mala...

  3. Synthetic Rock Analogue for Permeability Studies of Rock Salt with Mudstone

    Directory of Open Access Journals (Sweden)

    Hongwu Yin

    2017-09-01

    Full Text Available Knowledge about the permeability of surrounding rock (salt rock and mudstone interlayer is an important topic, which acts as a key parameter to characterize the tightness of gas storage. The goal of experiments that test the permeability of gas storage facilities in rock salt is to develop a synthetic analogue to use as a permeability model. To address the permeability of a mudstone/salt layered and mixed rock mass in Jintan, Jiangsu Province, synthetic mixed and layered specimens using the mudstone and the salt were fabricated for permeability testing. Because of the gas “slippage effect”, test results are corrected by the Klinkenberg method, and the permeability of specimens is obtained by regression fitting. The results show that the permeability of synthetic pure rock salt is 6.9 × 10−20 m2, and its porosity is 3.8%. The permeability of synthetic mudstone rock is 2.97 × 10−18 m2, with a porosity 17.8%. These results are close to those obtained from intact natural specimens. We also find that with the same mudstone content, the permeability of mixed specimens is about 40% higher than for the layered specimens, and with an increase in the mudstone content, the Klinkenberg permeability increases for both types of specimens. The permeability and mudstone content have a strong exponential relationship. When the mudstone content is below 40%, the permeability increases only slightly with mudstone content, whereas above this threshold, the permeability increases rapidly with mudstone content. The results of the study are of use in the assessment of the tightness of natural gas storage facilities in mudstone-rich rock salt formations in China.

  4. System level permeability modeling of porous hydrogen storage materials.

    Energy Technology Data Exchange (ETDEWEB)

    Kanouff, Michael P.; Dedrick, Daniel E.; Voskuilen, Tyler (Purdue University, West Lafayette, IN)

    2010-01-01

    A permeability model for hydrogen transport in a porous material is successfully applied to both laboratory-scale and vehicle-scale sodium alanate hydrogen storage systems. The use of a Knudsen number dependent relationship for permeability of the material in conjunction with a constant area fraction channeling model is shown to accurately predict hydrogen flow through the reactors. Generally applicable model parameters were obtained by numerically fitting experimental measurements from reactors of different sizes and aspect ratios. The degree of channeling was experimentally determined from the measurements and found to be 2.08% of total cross-sectional area. Use of this constant area channeling model and the Knudsen dependent Young & Todd permeability model allows for accurate prediction of the hydrogen uptake performance of full-scale sodium alanate and similar metal hydride systems.

  5. Is vertebrate mortality correlated to potential permeability by underpasses along low-traffic roads?

    Science.gov (United States)

    Delgado, Juan D; Morelli, Federico; Arroyo, Natalia L; Durán, Jorge; Rodríguez, Alexandra; Rosal, Antonio; Palenzuela, María Del Valle; Rodríguez, Jesús D G P

    2018-09-01

    Road permeability to animal movements depends among several factors on structures which, integrated in the road design, operate as safe conducts to mitigate vehicle collision and barrier effects. There is abundant evidence that wildlife makes use of such structures as safe passages to cross roads. We analyzed the spatial relationship between road drainage elements (N = 253; mostly culverts) as potential faunal underpasses, and mortality due to vehicle collisions in two seasons and on four relatively low-traffic roads (roads, identifying and characterizing all potential underpasses. Overall frequencies of casualties and spatial distribution were highly variable both within and among these roads. We obtained an estimation of potential permeability for the different roads. We detected, located and described a wide supply and a very variable pattern of drainage culverts and other underpasses, with differences among roads in passage attributes potentially affecting permeability for wildlife, such as spatial arrangement, number, density (frequency or concentration of passages) and dimensions. We used Mantel tests to assess spatial congruence of passages and road-killed animals. We applied generalized linear mixed models fitted by maximum likelihood through Akaike Information Criterion to explain the variation in the distance of the 238 casualties to the nearest underpasses, with road transect and season as random factors, and traffic intensity, speed and vertebrate class as fixed effects. Both road-killed animals and underpass distribution followed aggregated patterns, and casualties were not significantly related to underpasses along any of the 4 roads. There were no differences in distance of casualties to the nearest underpass for the three vertebrate classes. Although existing underpasses were abundant, we could not correlate potential permeability with reduced mortality along these roads, and other factors potentially affecting roadkill aggregations should be

  6. Time to eat? The relationship between food security and food-related time use.

    Science.gov (United States)

    Beatty, Timothy K M; Nanney, M Susie; Tuttle, Charlotte

    2014-01-01

    In the present analysis, we seek to establish a relationship between time spent on food-related activities and food security status as well as between time spent on these activities and Supplemental Nutrition Assistance Program (SNAP, formerly called the Food Stamp Program) participation and benefit level. After matching similar households using Coarsened Exact Matching, we estimate the relationship between food-related time, food insecurity and SNAP participation and benefit level using a comprehensive data set that combines two subsets of the Current Population Survey from years 2004-2010: the Food Security Supplement and the American Time Use Survey. City, suburban and rural areas of the USA. Non-institutionalized US population over the age of 15 years. Total sample size is 10 247 households. In single households, food insecurity and SNAP participation are associated with 20% more time in meal preparation and 13% less time eating. Similarly, in married households, SNAP participation and benefit level are associated with 32% less time in meal preparation while food insecurity is associated with 17% less time eating and 14% less time in grocery shopping. A significant relationship exists between time spent on food-related activities and food insecurity and SNAP. This implies that federal and state government may need to consider the time constraints many low-income households face when reforming food assistance programmes.

  7. Variation in social relationships relates to song preferences and EGR1 expression in a female songbird.

    Science.gov (United States)

    Schubloom, Hannah E; Woolley, Sarah C

    2016-09-01

    Social experiences can profoundly shape social behavior and the underlying neural circuits. Across species, the formation of enduring social relationships is associated with both neural and behavioral changes. However, it remains unclear how longer-term relationships between individuals influence brain and behavior. Here, we investigated how variation in social relationships relates to variation in female preferences for and neural responses to song in a pair-bonding songbird. We assessed variation in the interactions between individuals in male-female zebra finch pairs and found that female preferences for their mate's song were correlated with the degree of affiliation and amount of socially modulated singing, but not with the frequency of aggressive interactions. Moreover, variation in measures of pair quality and preference correlated with variation in the song-induced expression of EGR1, an immediate early gene related to neural activity and plasticity, in brain regions important for auditory processing and social behavior. For example, females with weaker preferences for their mate's song had greater EGR1 expression in the nucleus Taeniae, the avian homologue of the mammalian medial amygdala, in response to playback of their mate's courtship song. Our data indicate that the quality of social interactions within pairs relates to variation in song preferences and neural responses to ethologically relevant stimuli and lend insight into neural circuits sensitive to social information. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1029-1040, 2016. © 2016 Wiley Periodicals, Inc.

  8. Permeability model of sintered porous media: analysis and experiments

    Science.gov (United States)

    Flórez Mera, Juan Pablo; Chiamulera, Maria E.; Mantelli, Marcia B. H.

    2017-11-01

    In this paper, the permeability of porous media fabricated from copper powder sintering process was modeled and measured, aiming the use of the porosity as input parameter for the prediction of the permeability of sintering porous media. An expression relating the powder particle mean diameter with the permeability was obtained, based on an elementary porous media cell, which is physically represented by a duct formed by the arrangement of spherical particles forming a simple or orthorhombic packing. A circular duct with variable section was used to model the fluid flow within the porous media, where the concept of the hydraulic diameter was applied. Thus, the porous is modeled as a converging-diverging duct. The electrical circuit analogy was employed to determine two hydraulic resistances of the cell: based on the Navier-Stokes equation and on the Darcýs law. The hydraulic resistances are compared between themselves and an expression to determine the permeability as function of average particle diameter is obtained. The atomized copper powder was sifted to reduce the size dispersion of the particles. The porosities and permeabilities of sintered media fabricated from powders with particle mean diameters ranging from 20 to 200 microns were measured, by means of the image analysis method and using an experimental apparatus. The permeability data of a porous media, made of copper powder and saturated with distilled water, was used to compare with the permeability model. Permeability literature models, which considers that powder particles have the same diameter and include porosity data as input parameter, were compared with the present model and experimental data. This comparison showed to be quite good.

  9. The coupling of dynamics and permeability in the hydrocarbon accumulation period controls the oil-bearing potential of low permeability reservoirs: a case study of the low permeability turbidite reservoirs in the middle part of the third member of Shahejie Formation in Dongying Sag

    DEFF Research Database (Denmark)

    Yang, Tian; Cao, Ying-Chang; Wang, Yan-Zhong

    2016-01-01

    The relationships between permeability and dynamics in hydrocarbon accumulation determine oilbearing potential (the potential oil charge) of low permeability reservoirs. The evolution of porosity and permeability of low permeability turbidite reservoirs of the middle part of the third member...... facies A and diagenetic facies B do not develop accumulation conditions with low accumulation dynamics in the late accumulation period for very low permeability. At more than 3000 m burial depth, a larger proportion of turbidite reservoirs are oil charged due to the proximity to the source rock. Also...

  10. Permeability log using new lifetime measurements

    International Nuclear Information System (INIS)

    Dowling, D.J.; Boyd, J.F.; Fuchs, J.A.

    1975-01-01

    Comparative measurements of thermal neutron decay time are obtained for a formation after irradiation with a pulsed neutron source. Chloride ions in formation fluids are concentrated by the electrosmosis effect using charged poles on a well logging sonde. The formation is irradiated with fast neutrons and a first comparative measure of the thermal neutron decay time or neutron lifetime is taken. The chloride ions are then dispersed by acoustic pumping with a magnetostrictive transducer. The formation is then again irradiated with fast neutrons and a comparative measure of neutron lifetime is taken. The comparison is a function of the variation in chloride concentration between the two measurements which is related to formation permeability

  11. Nitric oxide turnover in permeable river sediment

    DEFF Research Database (Denmark)

    Schreiber, Frank; Stief, Peter; Kuypers, Marcel M M

    2014-01-01

    We measured nitric oxide (NO) microprofiles in relation to oxygen (O2) and all major dissolved N-species (ammonium, nitrate, nitrite, and nitrous oxide [N2O]) in a permeable, freshwater sediment (River Weser, Germany). NO reaches peak concentrations of 0.13 μmol L-1 in the oxic zone and is consumed......-nitroso-N-acetylpenicillamine (SNAP) (1) confirmed denitrification as the main NO consumption pathway, with N2O as its major product, (2) showed that denitrification combines one free NO molecule with one NO molecule formed from nitrite to produce N2O, and (3) suggested that NO inhibits N2O reduction....

  12. Relationship between cancer-related fatigue and physical activity in inpatient cancer rehabilitation.

    Science.gov (United States)

    Kummer, Franziska; Catuogno, Silvio; Perseus, Josef M; Bloch, Wilhelm; Baumann, Freerk T

    2013-08-01

    Fatigue is a serious problem for the majority of patients with cancer. In this context, several studies have shown benefits of physical activity during and following treatment. However, uncertainties remain regarding the optimal type and duration of physical activity. Therefore, this study examined the relationship between cancer-related fatigue and physical activity in the course of inpatient rehabilitation. Fatigue (Multidimensional Fatigue Inventory) and physical activity (Freiburg Questionnaire of Physical Activity) were assessed in a consecutive series of 35 patients with cancer attending oncological inpatient rehabilitation during a six-month study period. The three-week rehabilitation program included daily exercise therapy consisting of aerobic endurance training, moderate resistance training, coordination exercises, relaxation training and individual physiotherapy. At discharge, a significant improvement in each dimension of cancer-related fatigue (p=0.001-0.003) and a significant increase of physical activity levels (p=0.001) were observed. A small, but significant negative correlation was found between cancer-related fatigue and the level of physical activity (R=-0.438, p=0.004). The largest effects were associated with a weekly energy expenditure of 3000 kcal through physical activity. The results support a non-linear dose-response relationship between cancer-related fatigue and physical activity. Since this is the first study providing specific exercise recommendations for an effective treatment of cancer-related fatigue in the context of inpatient rehabilitation, further research is required to validate the observed trends.

  13. Quantifying Evaporation in a Permeable Pavement System

    Science.gov (United States)

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  14. Permeable Pavement Research - Edison, New Jersey

    Science.gov (United States)

    This presentation provides the background and summary of results collected at the permeable pavement parking lot monitored at the EPA facility in Edison, NJ. This parking lot is surfaced with permeable interlocking concrete pavers (PICP), pervious concrete, and porous asphalt. ...

  15. Causal Relationship Between Relative Price Variability and Inflation in Turkey: Evidence from Panel Data

    Directory of Open Access Journals (Sweden)

    Nebiye Yamak

    2016-06-01

    Full Text Available This study investigates the causal relationship between inflation and relative price variability in Turkey for the period of January 2003-January 2014, by using panel data. In the study, a Granger (1969 non-causality test in heterogeneous panel data models developed by Dumitrescu and Hurlin (2012 is utilized to determine the causal relations between inflation rate relative price variability. The panel data consists of 4123 observations: 133 time observations and 31 cross-section observations. The results of panel causality test indicate that there is a bidirectional causality between inflation rate and relative price variability by not supporting the imperfection information model of Lucas and the menu cost model of Ball and Mankiw.

  16. Quantifying porosity, compressibility and permeability in Shale

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Frykman, Peter

    strain data. We found that Kozeny's modelled permeability fall in the same order of magnitude with measured permeability for shale rich in kaolinite but overestimates permeability by two to three orders of magnitudes for shale with high content of smectite. The empirical Yang and Aplin model gives good...... permeability estimate comparable to the measured one for shale rich in smectite. This is probably because Yang and Aplin model was calibrated in London clay which is rich in smectite....

  17. Gender Difference in Relationship between Health-Related Quality of Life and Work Status.

    Science.gov (United States)

    Noh, Jin-Won; Kim, Jinseok; Park, Jumin; Kim, Hyun-Jung; Kwon, Young Dae

    2015-01-01

    This study investigated the association of employment status with health-related quality of life in adult Koreans, as well as the gender difference in the relationship, using a large, nationally representative sample. Using data from the Korea Health Panel survey, we examined the relationship between quality of life measured by EQ-5D and work status among Korean adults. We also tested whether and how the relationship between quality of life and work status differed by gender. Quality of life among working adults was better than among non-working adults. The gap between the two groups was larger among male than female participants. Further, the gender differential effect was larger in the 41-60-year-old age group than in the 18-40-year-old and 61-or-older groups. Being employed has a positive relation to quality of life among adults. Work status plays a more important role in quality of life for men than for women, especially for the working elderly men than working elderly women.

  18. Gender Difference in Relationship between Health-Related Quality of Life and Work Status.

    Directory of Open Access Journals (Sweden)

    Jin-Won Noh

    Full Text Available This study investigated the association of employment status with health-related quality of life in adult Koreans, as well as the gender difference in the relationship, using a large, nationally representative sample. Using data from the Korea Health Panel survey, we examined the relationship between quality of life measured by EQ-5D and work status among Korean adults. We also tested whether and how the relationship between quality of life and work status differed by gender. Quality of life among working adults was better than among non-working adults. The gap between the two groups was larger among male than female participants. Further, the gender differential effect was larger in the 41-60-year-old age group than in the 18-40-year-old and 61-or-older groups. Being employed has a positive relation to quality of life among adults. Work status plays a more important role in quality of life for men than for women, especially for the working elderly men than working elderly women.

  19. Examining the relation between adolescent social anxiety, adolescent delinquency (abstention), and emerging adulthood relationship quality.

    Science.gov (United States)

    Mercer, Natalie; Crocetti, Elisabetta; Meeus, Wim; Branje, Susan

    2017-07-01

    Social anxiety symptoms and delinquency are two prevalent manifestations of problem behavior during adolescence and both are related to negative interpersonal relationships in adolescence and emerging adulthood. This study examined the relation between social anxiety and delinquency in adolescence and the interplay between adolescent social anxiety and delinquency on perceived relationship quality in emerging adulthood. In a 10-year long prospective study (T1, n = 923; T2, n = 727; Mage T1 = 12; 49% female), we examined competing hypotheses using regression analyses: the protective perspective, which suggests social anxiety protects against delinquency; and the co-occurring perspective, which suggests social anxiety and delinquency co-occur leading to increased negative interpersonal outcomes. In adolescence, the relation between social anxiety and delinquency was consistent with the protective perspective. In emerging adulthood, consistent with the co-occurring perspective, ever-delinquents (but not delinquency abstainers) with higher social anxiety reported less perceived best friend, mother, and father support compared to delinquents with lower social anxiety. There was no interaction between anxiety and delinquency in predicting perceived conflict. This study highlights the importance of examining the relation between social anxiety and delinquency with regards to different interpersonal outcomes.

  20. Viscous fingering with permeability heterogeneity

    International Nuclear Information System (INIS)

    Tan, C.; Homsy, G.M.

    1992-01-01

    Viscous fingering in miscible displacements in the presence of permeability heterogeneities is studied using two-dimensional simulations. The heterogeneities are modeled as stationary random functions of space with finite correlation scale. Both the variance and scale of the heterogeneities are varied over modest ranges. It is found that the fingered zone grows linearly in time in a fashion analogous to that found in homogeneous media by Tan and Homsy [Phys. Fluids 31, 1330 (1988)], indicating a close coupling between viscous fingering on the one hand and flow through preferentially more permeable paths on the other. The growth rate of the mixing zone increases monotonically with the variance of the heterogeneity, as expected, but shows a maximum as the correlation scale is varied. The latter is explained as a ''resonance'' between the natural scale of fingers in homogeneous media and the correlation scale

  1. Cerebral arteriovenous malformations. the relationship between clinical related events and rCBF SPECT imaging

    International Nuclear Information System (INIS)

    Sun Bo; Shi Xiangen

    1996-01-01

    To evaluate the relationship between clinical related events and rCBF SPECT imaging in patients with arteriovenous malformations (AVMs), the radioactive counting difference between normal and lesion site was divided by regional pixel considered as ischemic index (II). II was measured in 20 AVM cases and compared with patients' age, sex,neurological history and the size of lesions. The degree of rCBF reduction correlated with clinical neurological manifestation and showed no significant relationship with the age, sex and size of malformed vessels. II in patients with seizures was higher than that in patients with hemorrhage. The rCBF SPECT imaging may be useful for evaluation of the hemodynamics in AVMs

  2. [The reciprocity rule in the construction of relationships as the key in relational processes].

    Science.gov (United States)

    Fenelli, Antonio; Volpi, Cecilia; Guarracino, Emanuele; Galli, Virginia; Esposito, Massimo

    2011-01-01

    Reciprocity as an expression of the therapist-patient relationship is pointed-out by Mario Reda who refers to Comparetti's studies on the mother-foetus reciprocity, mediated by the so-called "jumps". Reciprocal behaviours are clearly observable during bird and other animal courtship behaviour, whereas in the Sapiens sapiens species, we may observe the establishing of a very complex reciprocity system, which starts with gestures and bodily attitudes, subsequently activating sensory-motor emotional schemata and internal working models, thus enabling the construction of personal meanings. A relationship may result from an encounter provided that "compatible" meanings are constructed in the context of "possible reciprocity" of significant systems. The observation of reciprocity provides a concrete possibility to reduce the risk of absolute subjectivity related to the I or the you, superceding it through the us.

  3. Model of Communication Strategy for Public Relations in Private University in Building the Relationship with the Media

    OpenAIRE

    Darmastuti, Rini; Sinatra Wijaya, Lina

    2009-01-01

    The success of Public Relations work in Private University depends on the public relations strategy in building the relationship with the media. For knowing how effective PR strategy is in building the relationship with the media, A research has been done with 10 respondents ( 10 Private Universities in Central Java ) by using descriptive qualitative approach and direct observation. There are two relationship models that have been found from this research, they are “ Imbalanced Commensalisms ...

  4. Modeling of Multiphase with Respect to Low Interfacial Tension by Pseudo-Two-Phase Relative Permeability Functions Modélisation d'un écoulement polyphasique à faible tension interfaciale par des fonctions pseudo-biphasiques de perméabilité relative

    Directory of Open Access Journals (Sweden)

    Pusch G.

    2006-11-01

    Full Text Available A new 2-parameter desaturation function is introduced which offers a broader range of applicability to reservoir rock. Based on this function two-phase relative permeabilities are derived for oil phase and microemulsion flow. These functions are used to match a laboratory experiment by using surfactant flooding for a single surfactant system. Les auteurs présentent une nouvelle fonction de désaturation à deux paramètres qui offre une plus large gamme de possibilités d'application aux roches réservoir. On tire de cette fonction des perméabilités relatives biphasiques pour l'écoulement de la phase pétrole et d'une microémulsion. Ces fonctions sont utilisées pour reproduire une expérience de laboratoire avec injection de surfactant pour un seul système surfactant.

  5. Gender matters: the relationship between social anxiety and alcohol-related consequences.

    Science.gov (United States)

    Schry, Amie R; Norberg, Melissa M; Maddox, Brenna B; White, Susan W

    2014-01-01

    Identification of risk factors for alcohol-related consequences is an important public health concern. Both gender and social anxiety have been associated with alcohol-related consequences broadly, but it is unknown whether these variables are differentially related to specific types of alcohol-related consequences for American college students. In the present study, 573 undergraduate students (M(age) = 19.86 years, SD = 1.40; range 18 to 25; 68.9% female) completed an on-line assessment of social anxiety, alcohol use, and four types of alcohol-related consequences (personal, social, physical, and role). Poisson regressions were run to examine social anxiety, gender, and the interaction between social anxiety and gender as predictors of each type of alcohol-related consequences. After controlling for alcohol use, social anxiety was positively associated with all four types of consequences, and females endorsed higher rates of physical, personal, and role consequences. The interaction between social anxiety and gender was statistically significant only for physical consequences, with social anxiety having a stronger effect for males. These findings, which diverge somewhat from those of a prior study with Australian college students, are discussed in the context of a biopsychosocial model of social anxiety and substance use problems. This study highlights the importance of further investigating cultural differences in the relationships among social anxiety, gender, and alcohol-related consequences.

  6. Gender matters: the relationship between social anxiety and alcohol-related consequences.

    Directory of Open Access Journals (Sweden)

    Amie R Schry

    Full Text Available BACKGROUND AND OBJECTIVES: Identification of risk factors for alcohol-related consequences is an important public health concern. Both gender and social anxiety have been associated with alcohol-related consequences broadly, but it is unknown whether these variables are differentially related to specific types of alcohol-related consequences for American college students. METHODS: In the present study, 573 undergraduate students (M(age = 19.86 years, SD = 1.40; range 18 to 25; 68.9% female completed an on-line assessment of social anxiety, alcohol use, and four types of alcohol-related consequences (personal, social, physical, and role. Poisson regressions were run to examine social anxiety, gender, and the interaction between social anxiety and gender as predictors of each type of alcohol-related consequences. RESULTS: After controlling for alcohol use, social anxiety was positively associated with all four types of consequences, and females endorsed higher rates of physical, personal, and role consequences. The interaction between social anxiety and gender was statistically significant only for physical consequences, with social anxiety having a stronger effect for males. DISCUSSION AND CONCLUSIONS: These findings, which diverge somewhat from those of a prior study with Australian college students, are discussed in the context of a biopsychosocial model of social anxiety and substance use problems. SCIENTIFIC SIGNIFICANCE: This study highlights the importance of further investigating cultural differences in the relationships among social anxiety, gender, and alcohol-related consequences.

  7. The relationship between optical guiding and the relative phase in free-electron lasers

    International Nuclear Information System (INIS)

    Freund, H.P.; Antonsen, T.M. Jr.

    1991-01-01

    In this paper the relationship between the relative phase and optical guiding in the free-electron laser is studied. The relative phase in this case is defined as the shift in the wavenumber from the vacuum value integrated over the interaction length. In terms of the optical guiding of the signal in free-electron lasers, the relative phase must be positive in order for refractive guiding of the signal to occur. The relative phase is studied from the standpoint of the linear stability analysis in both the high- and low-gain regimes, and the qualitative implications in each of these regimes of the relative phase on the refractive guiding of the signal are identical. Specifically, the relative phase is found to be negative at the low-frequency over this band until it turns positive at a frequency approximately 10% below the frequency of peak gain. Thus optical guiding is indicated over a large portion, but not all, of the gain band. A quantitative measure of the optical guiding of the signal is obtained by an analytic formulation of the guiding of the signal. This formulation is based upon a separable beam approximation in which the evolution of the signal is determined by a Green's function analysis. The specific example of interest involves the low-gain regime prior to saturation. In this case, it is shown that the analytic result is in substantial agreement with the calculation of the relative phase

  8. Gender Matters: The Relationship between Social Anxiety and Alcohol-Related Consequences

    Science.gov (United States)

    Schry, Amie R.; Norberg, Melissa M.; Maddox, Brenna B.; White, Susan W.

    2014-01-01

    Background and Objectives Identification of risk factors for alcohol-related consequences is an important public health concern. Both gender and social anxiety have been associated with alcohol-related consequences broadly, but it is unknown whether these variables are differentially related to specific types of alcohol-related consequences for American college students. Methods In the present study, 573 undergraduate students (M age = 19.86 years, SD = 1.40; range 18 to 25; 68.9% female) completed an on-line assessment of social anxiety, alcohol use, and four types of alcohol-related consequences (personal, social, physical, and role). Poisson regressions were run to examine social anxiety, gender, and the interaction between social anxiety and gender as predictors of each type of alcohol-related consequences. Results After controlling for alcohol use, social anxiety was positively associated with all four types of consequences, and females endorsed higher rates of physical, personal, and role consequences. The interaction between social anxiety and gender was statistically significant only for physical consequences, with social anxiety having a stronger effect for males. Discussion and Conclusions These findings, which diverge somewhat from those of a prior study with Australian college students, are discussed in the context of a biopsychosocial model of social anxiety and substance use problems. Scientific Significance This study highlights the importance of further investigating cultural differences in the relationships among social anxiety, gender, and alcohol-related consequences. PMID:25541722

  9. Changes in sapwood permeability and anatomy with tree age and height in the broad-leaved evergreen species Eucalyptus regnans.

    Science.gov (United States)

    England, Jacqueline R; Attiwill, Peter M

    2007-08-01

    Increases in plant size and structural complexity with increasing age have important implications for water flow through trees. Water supply to the crown is influenced by both the cross-sectional area and the permeability of sapwood. It has been hypothesized that hydraulic conductivity within sapwood increases with age. We investigated changes in sapwood permeability (k) and anatomy with tree age and height in the broad-leaved evergreen species Eucalyptus regnans F. Muell. Sapwood was sampled at breast height from trees ranging from 8 to 240 years old, and at three height positions on the main stem of 8-year-old trees. Variation in k was not significant among sampling height positions in young trees. However, k at breast height increased with tree age. This was related to increases in both vessel frequency and vessel diameter, resulting in a greater proportion of sapwood being occupied by vessel lumina. Sapwood hydraulic conductivity (the product of k and sapwood area) also increased with increasing tree age. However, at the stand level, there was a decrease in forest sapwood hydraulic conductivity with increasing stand age, because of a decrease in the number of trees per hectare. Across all ages, there were significant relationships between k and anatomy, with individual anatomical characteristics explaining 33-62% of the variation in k. There was also strong agreement between measured k and permeability predicted by the Hagen-Poiseuille equation. The results support the hypothesis of an increase in sapwood permeability at breast height with age. Further measurements are required to confirm this result at other height positions in older trees. The significance of tree-level changes in sapwood permeability for stand-level water relations is discussed.

  10. Permeability of protective coatings to tritium

    International Nuclear Information System (INIS)

    Braun, J.M.

    1987-10-01

    The permeability of four protective coatings to tritium gas and tritiated water was investigated. The coatings, including two epoxies, one vinyl and one urethane, were selected for their suitability in CANDU plant service in Ontario Hydro. Sorption rates of tritium gas into the coatings were considerably larger than for tritiated water, by as much as three to four orders of magnitude. However, as a result of the very large solubility of tritiated water in the coatings, the overall permeability to tritium gas and tritiated water are comparable, being somewhat larger for HTO. Marked differences were also evident among the four coatings, the vinyl proving to be unique in behaviour and morphology. Because of a highly porous surface structure water condensation takes place at high relative humidities, leading to an abnormally high retention of free water. Desorption rates from the four coatings were otherwise quite similar. Of practical importance was the observation that more effective desorption of tritiated water could be carried out at relatively high humidities, in this case 60%. It was believed that isotopic exchange was responsible for this phenomenon. It appears that epoxy coatings having a high pigment-to-binder ratio are most suited for coating concrete in tritium handling facilities

  11. Parental recall, attachment relating and self-attacking/self-reassurance: their relationship with depression.

    Science.gov (United States)

    Irons, C; Gilbert, P; Baldwin, M W; Baccus, J R; Palmer, M

    2006-09-01

    When things go wrong for people they can become self-critical or focus on positive, reassuring aspects of the self. This study explored the relationship between forms of self-criticism and self-reassurance, recall of parental experiences and attachment style in relation to depressed symptoms in students. A sample of 197 undergraduate students from the UK and Canada completed self-report questionnaires measuring recall of parental styles, attachment, forms of self-criticism, self-reassurance, and depression symptoms. Recall of parents as rejecting and overprotecting was significantly related to both inadequacy and self-hating self-criticism. In contrast, parental warmth was negatively correlated with these forms of self-criticism. In addition, when things go wrong for the person, recall of parental warmth was associated with the ability to be self-reassuring. A mediator analysis suggested that (I) the impact of recall of negative parenting on depression is mediated through the forms of self-criticism and (2) the effect of parental warmth on depression was mediated by the ability to be self-reassuring. The impacts of negative parenting styles may translate into vulnerabilities to depression via the way children (and later adults) develop their self-to-self relating (e.g. as self-critical versus self-reassuring). Hence, there is a need for further research on the link between attachment experiences, recall of parental rejection/warmth and their relationship to internal, self-evaluative and affect systems in creating vulnerabilities to psychopathology.

  12. The Relationship between an Invasive Shrub and Soil Moisture: Seasonal Interactions and Spatially Covarying Relations

    Directory of Open Access Journals (Sweden)

    Yuhong He

    2014-09-01

    Full Text Available Recent studies indicate that positive relationships between invasive plants and soil can contribute to further plant invasions. However, it remains unclear whether these relations remain unchanged throughout the growing season. In this study, spatial sequences of field observations along a transect were used to reveal seasonal interactions and spatially covarying relations between one common invasive shrub (Tartarian Honeysuckle, Lonicera tatarica and soil moisture in a tall grassland habitat. Statistical analysis over the transect shows that the contrast between soil moisture in shrub and herbaceous patches vary with season and precipitation. Overall, a negatively covarying relationship between shrub and soil moisture (i.e., drier surface soils at shrub microsites exists during the very early growing period (e.g., May, while in summer a positively covarying phenomenon (i.e., wetter soils under shrubs is usually evident, but could be weakened or vanish during long precipitation-free periods. If there is sufficient rainfall, surface soil moisture and leaf area index (LAI often spatially covary with significant spatial oscillations at an invariant scale (which is governed by the shrub spatial pattern and is about 8 m, but their phase relation in space varies with season, consistent with the seasonal variability of the co-varying phenomena between shrub invasion and soil water content. The findings are important for establishing a more complete picture of how shrub invasion affects soil moisture.

  13. Age-related prevalence of chronic rhinosinusitis and nasal polyps and their relationships with asthma onset.

    Science.gov (United States)

    Won, Ha-Kyeong; Kim, Young-Chan; Kang, Min-Gyu; Park, Han-Ki; Lee, Seung-Eun; Kim, Min-Hye; Yang, Min-Suk; Chang, Yoon-Seok; Cho, Sang-Heon; Song, Woo-Jung

    2018-04-01

    Chronic rhinosinusitis (CRS) is a major disease condition with high morbidity and can influence lower airway disease status in adults. However, its associations with adult asthma onset and activity have not been examined in detail in a general adult population. To investigate relationships between CRS with nasal polyps (CRSwNP) and asthma characteristics. A cross-sectional data set of 17,506 adult participants (≥18 years old) in the Korean National Health and Nutrition Examination Survey from 2010 through 2012 was analyzed. CRS was defined using structured questionnaires according to the international guideline, and presence of nasal polyps was objectively assessed using nasal endoscopy. Presence of asthma and its onset and current activity were assessed using structured questionnaires. CRS was significantly related to asthma, but the relationships were distinct by CRS and asthma status. CRSwNP was significantly associated with adult-onset asthma (onset after 18 years of age) or late-onset asthma (onset after 40 years of age), whereas CRS without nasal polyps was related to childhood-onset asthma (onset before 18 years) or early-onset asthma (onset before 40 years) in adults. The 2 CRS subgroups showed significant associations with current asthma but not with past asthma. However, the comorbid asthma rate was lower than 10% among subjects with CRS. This study found distinct age-related patterns of CRSwNP and asthma and demonstrated their significant associations in a general population. However, the low prevalence of asthma in CRSwNP is in sharp contrast to findings in Western populations, which warrants further investigation for ethnic or regional differences in relationships between CRSwNP and asthma. Copyright © 2018 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  14. Some additional results on the directional relationships between forces and accelerations in special relativity

    International Nuclear Information System (INIS)

    Gonzalez-Diaz, P.F.

    1979-01-01

    Some directional relationships between forces and accelerations in special relativity have been studied by considering the most general case of a body having x, y and z components of velocity, which is acted upon by a force with nonzero components. The behaviour of asub(y)/asub(x) and asub(y)/asub(z) vs. velocity for different force component ratios is studied in the general situation in which vsub(x) is unequal to vsub(y) is unequal to vsub(z). It is shown that one or two, suddenly varying, negative acceleration components can result for the body at sufficiently high velocities, and an explanation is given. (author)

  15. Contribution of WUSCHEL-related homeobox (WOX genes to identify the phylogenetic relationships among Petunia species

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Anversa Segatto

    Full Text Available Abstract Developmental genes are believed to contribute to major changes during plant evolution, from infrageneric to higher levels. Due to their putative high sequence conservation, developmental genes are rarely used as molecular markers, and few studies including these sequences at low taxonomic levels exist. WUSCHEL-related homeobox genes (WOX are transcription factors exclusively present in plants and are involved in developmental processes. In this study, we characterized the infrageneric genetic variation of Petunia WOX genes. We obtained phylogenetic relationships consistent with other phylogenies based on nuclear markers, but with higher statistical support, resolution in terminals, and compatibility with flower morphological changes.

  16. Effect of aggregate grain size distribution on properties of permeable ...

    African Journals Online (AJOL)

    ) ratio on the mechanical properties of permeable concrete is investigated. The aim of this study is to prepare permeable concrete mixture with optimum properties in terms of strength and permeability. For this purpose, five different permeable ...

  17. Permeability of hydrogen isotopes through Pd-Ag membrane

    International Nuclear Information System (INIS)

    Yoshida, Hiroshi

    1981-01-01

    This paper represents the permeabilities, diffusion coefficients and isotope effects for hydrogen and deuterium through Pd-25 wt.% Ag alloy tubes The feed gas H 2 or D 2 flowing into the permeation cell was preheated before it reached to the outer surface of the permeation tube made of palladium-silver alloy. Permeation time lag method could be successfully carried out with the present apparatus to measure both permeability and diffusion coefficient. The square-root pressure dependence for the permeation of hydrogen isotopes was observed. The observed systematic temperature dependence indicates that the approximation of the Arrhenius' relation was effective within this experimental conditions. Some tendency of permeation fluxes in relation to the reciprocal temperature, 1/T, was seen. The permeability ratio was larger than the square root of isotopic mass ratio, and it decreased with temperature rise. On the contrary, the diffusion coefficient ratio was much smaller than the square root of isotopic mass ratio. (Kato, T.)

  18. Relationships among supervisor feedback environment, work-related stressors, and employee deviance.

    Science.gov (United States)

    Peng, Jei-Chen; Tseng, Mei-Man; Lee, Yin-Ling

    2011-03-01

    Previous research has demonstrated that the employee deviance imposes enormous costs on organizational performance and productivity. Similar research supports the positive effect of favorable supervisor feedback on employee job performance. In light of such, it is important to understand the interaction between supervisor feedback environment and employee deviant behavior to streamline organization operations. The purposes of this study were to explore how the supervisor feedback environment influences employee deviance and to examine the mediating role played by work-related stressors. Data were collected from 276 subordinate-supervisor dyads at a regional hospital in Yilan. Structural equation modeling analyses were conducted to test hypotheses. Structural equation modeling analysis results show that supervisor feedback environment negatively related to interpersonal and organizational deviance. Moreover, work-related stressors were found to partially mediate the relationship between supervisor feedback environment and employee deviance. Study findings suggest that when employees (nurses in this case) perceive an appropriate supervisor-provided feedback environment, their deviance is suppressed because of the related reduction in work-related stressors. Thus, to decrease deviant behavior, organizations may foster supervisor integration of disseminated knowledge such as (a) how to improve employees' actual performance, (b) how to effectively clarify expected performance, and (c) how to improve continuous performance feedback. If supervisors absorb this integrated feedback knowledge, they should be in a better position to enhance their own daily interactions with nurses and reduce nurses' work-related stress and, consequently, decrease deviant behavior.

  19. Teacher Perspectives of Interdisciplinary Coteaching Relationships in a Clinical Skills Course: A Relational Coordination Theory Analysis.

    Science.gov (United States)

    Daniel, Michelle M; Ross, Paula; Stalmeijer, Renée E; de Grave, Willem

    2018-01-01

    Phenomenon: Interdisciplinary coteaching has become a popular pedagogic model in medical education, yet there is insufficient research to guide effective practices in this context. Coteaching relationships are not always effective, which has the potential to affect the student experience. The purpose of this study was to explore interdisciplinary coteaching relationships between a physician (MD) and social behavioral scientist (SBS) in an undergraduate clinical skills course. We aimed to gain an in-depth understanding of what teachers perceive as influencing the quality of relationships to begin to construct a framework for collaborative teaching in medical education. A qualitative study was conducted consisting of 12 semistructured interviews (6 MD and 6 SBS) and 2 monodisciplinary focus groups. Sampling was purposive and aimed at maximal variation from among 64 possible faculty. The data were analyzed using the constant comparative method to develop a grounded theory. Five major themes resulted from the analysis that outline a framework for interdisciplinary coteaching: respect, shared goals, shared knowledge and understanding, communication, and complementary pairings. Insights: The first 4 themes align with elements of relational coordination theory, an organizational theory of collaborative practice that describes how work roles interact. The complementary pairings extend this theory from work roles to individuals, with unique identities and personal beliefs and values about teaching. Prior studies on coteaching have not provided a clear linkage to theory. The conceptual framework helps suggest future directions for coteaching research and has practical implications for administrative practices and faculty development. These findings contribute to the sparse research in medical education on interdisciplinary coteaching relationships.

  20. The permeability of concrete for reactor containment vessels

    International Nuclear Information System (INIS)

    Mills, R.H.

    1983-07-01

    Review of the literature pertaining to water, water vapour and gas transmission through concrete revealed conflicting views on the mechanisms involved and the influence of mix design parameters such as initial porosities and water/cement ratio. Consideration of the effects of ageing and of construction defects in field concrete were totally neglected in published work. Permeability data from three published papers were compared with permeability calculated according to Powers. The ratio of calculated to observed permeability varied from 40 x 10 -3 to 860 x 10 -3 for one group: from 0.17 x 10 3 to 8.6 x 10 3 in the second; and from 24 x 10 3 to 142 x 10 3 for the third. There were therefore wide discrepancies within each group of data and between groups. A bibliography was prepared and an exploratory experimental programme was mounted to determine the relative importance of key parameters such as cement type, porosity and water/cement ratio. Contrary to frequently cited references it was found that permeability of concrete was not significantly influenced by water/cement ratio when the starting porosity was constant. If water/cement ratio was held constant, however, the permeability was strongly influenced by starting porosity. It was also found that with constant water/cement ratio permeability increased with cement content. The value of fly ash and blast furnace slag in partial substitution for Portland cement is neglected in the literature but it is important since such substitutions alleviate alkali-silicate reactions. Permeability of concrete was significantly decreased by partial substitution of Portland cement with fly ash but there was no benefit in the use of blast furnace slag

  1. Relationship between Health Literacy, Health-Related Behaviors and Health Status: A Survey of Elderly Chinese

    Science.gov (United States)

    Liu, Yong-Bing; Liu, Liu; Li, Yan-Fei; Chen, Yan-Li

    2015-01-01

    Background: Despite the large volume of research dedicated to health-related behavior change, chronic disease costs continue to rise, thus creating a major public health burden. Health literacy, the ability to seek, understand, and utilize health information, has been identified as an important factor in the course of chronic conditions. Little research has been conducted on the relationship between health literacy and health-related behaviors and health status in elderly Chinese. The aim of this study was to elucidate the relationship between health literacy and health-related behaviors and health status in China. Methods: The subjects enrolled in this study were selected based on a stratified cluster random sampling design. Information involving >4500 older adults in 44 pension institutions in Urumqi, Changji, Karamay, and Shihezi of Xinjiang between September 2011 and June 2012 was collected. The Chinese Citizen Health Literacy Questionnaire (China Health Education Centre, 2008) and a Scale of the General Status were administered and the information was obtained through face-to-face inquiries by investigators. A total of 1452 respondents met the inclusion criteria. A total of 1452 questionnaires were issued and the valid response rate was 96.14% (1396 of 1452). Factors affecting health literacy and the relationship to health literacy were identified by one-way ANOVA and a multiple linear regression model. Results: The average health literacy level of the elderly in nursing homes was relatively low (71.74 ± 28.35 points). There were significant differences in the health literacy score among the factors of age, gender, race, education level, household income, marital conditions, and former occupation (p 0.05). Multiple linear regression analysis showed that the independent influencing factors of health literacy included education level, race, former occupation, household income, age, physical exercise, health examination, smoking, and health information access (p

  2. Relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae).

    Science.gov (United States)

    Blasina, Gabriela; Molina, Juan; Lopez Cazorla, Andrea; Díaz de Astarloa, Juan

    This study explores the relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae) that are known to differ in their trophic habits. Only adult specimens were analyzed: 103 Cynoscion guatucupa, 77 Pogonias cromis, 61 Micropogonias furnieri, and 48 Menticirrhus americanus. The four species presented divergent ecomorphological traits related to swimming agility, prey spotting and capture, and the potential size of prey they were able to swallow. Results suggest that these sciaenid species can partition the food resources, even though they completely overlap in space. Differences in their ecomorphological traits appear to correlate closely with the diet and consequently could explain the trophic differentiation observed. Arguably, these ecomorphological differences play a significant role in the coexistence of the adults of these sympatric fish species. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  3. Jealousy and violence in dating relationships: gender-related differences among a Spanish sample.

    Science.gov (United States)

    Sebastián, Julia; Verdugo, Alba; Ortiz, Beatriz

    2014-12-19

    The present study analyzes violent behavior (psychological, physical, and sexual violence) that may occur in dating relationships. Data was collected from couples of adolescents and young adults in a sample of 579 students from the region of Madrid, consisting of 319 females and 260 males aged between 12 and 22 years. A novel aspect of this study compared with the great majority of published studies is analysis of a) the frequency of violent behaviors (and not only their presence or absence) to study significant mean differences and b) potential gender and age related differences in the patterns of violence. Results indicate the high prevalence of violence in Spanish dating relationships. Specifically, females carry out more mild physical (p < .001) and psychological violence (p < .05), whereas males perpetrate more sexual violence (p < .001). However, with regard to victimization, no significant gender related differences in frequency were found between boys and girls in any type of violence. With regard to age, young adolescents perform (p < .05) and suffer (p < .01) significantly more jealous behavior, whereas the young adults of our sample commit and suffer more sexual violence (p < .05). Directions for future research are outlined, mainly concerning instruments used that ought to be more sensitive to the reality being measured.

  4. Relationship between weight-related behavioral profiles and health outcomes by sexual orientation and gender.

    Science.gov (United States)

    VanKim, Nicole A; Erickson, Darin J; Eisenberg, Marla E; Lust, Katherine; Rosser, B R Simon; Laska, Melissa N

    2016-07-01

    Examine relationships between weight-related factors and weight status, body dissatisfaction, chronic health conditions, and quality of life across sexual orientation and gender. Two- and four-year college students participated in the College Student Health Survey (n = 28,703; 2009-2013). Risk differences were calculated to estimate relationships between behavioral profiles and weight status, body satisfaction, diagnosis of a chronic condition, and quality of life, stratified by gender and sexual orientation. Four behavioral profiles, characterized as "healthier eating habits, more physically active," "healthier eating habits," "moderate eating habits," and "unhealthy weight control," were utilized based on latent class analyses, estimated from nine weight-related behavioral survey items. Sexual orientation differences in weight and quality of life were identified. For example, sexual minority groups reported significantly poorer quality of life than their heterosexual counterparts (females: 22.5%-38.6% (sexual minority) vs. 19.8% (heterosexual); males: 14.3%-26.7% (sexual minority) vs. 11.8% (heterosexual)). Compared with the "healthier eating habits, more physically active" profile, the "unhealthy weight control" profile was associated with obesity, poor body satisfaction, and poor quality of life in multiple gender/sexual orientation subgroups. Interventions are needed to address obesity, body dissatisfaction, and poor quality of life among sexual minority college students. © 2016 The Obesity Society.

  5. Relationship between relative cerebral blood flow, relative cerebral blood volume, and relative cerebral metabolic rate of oxygen in the preterm neonatal brain.

    Science.gov (United States)

    Nourhashemi, Mina; Kongolo, Guy; Mahmoudzadeh, Mahdi; Goudjil, Sabrina; Wallois, Fabrice

    2017-04-01

    The mechanisms responsible for coupling between relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), and relative cerebral metabolic rate of oxygen ([Formula: see text]), an important function of the microcirculation in preterm infants, remain unclear. Identification of a causal relationship between rCBF-rCBV and [Formula: see text] in preterms may, therefore, help to elucidate the principles of cortical hemodynamics during development. We simultaneously recorded rCBF and rCBV and estimated [Formula: see text] by two independent acquisition systems: diffuse correlation spectroscopy and near-infrared spectroscopy, respectively, in 10 preterms aged between 28 and 35 weeks of gestational age. Transfer entropy was calculated in order to determine the directionality between rCBF-rCBV and [Formula: see text]. The surrogate method was applied to determine statistical significance. The results show that rCBV and [Formula: see text] have a predominant driving influence on rCBF at the resting state in the preterm neonatal brain. Statistical analysis robustly detected the correct directionality of rCBV on rCBF and [Formula: see text] on rCBF. This study helps to clarify the early organization of the rCBV-rCBF and [Formula: see text] inter-relationship in the immature cortex.

  6. Revisiting relationships between sex-related variables and continuation in counseling.

    Science.gov (United States)

    Hatchett, Gregory T; Park, Heather L

    2004-04-01

    This study examined the relationships between three sex-related variables (client sex, therapist sex, and dyad matching on sex) and continuation in counseling. 245 college students who were clients at three university counseling centers participated. Consistent with previous studies, women comprised 68.2% of the clients seeking services at these counseling centers. Clients' sex was significantly related to counseling duration, explaining 2.2% of the common variance. Female clients, on the average, attended 1.8 more sessions than male clients. However, neither the therapists' sex nor dyad matching on sex was significantly related to the duration of counseling. None of the sex-related variables correlated with premature termination of counseling. The results have implications for providing counseling and outreach services to male students. Despite relatively equivalent rates in the incidence of mental health problems, female students continue to comprise the majority of clients. Therefore, university counseling centers need to communicate their services better to male students in need of mental health services.

  7. Current and evolving approaches for improving the oral permeability of BCS Class III or analogous molecules.

    Science.gov (United States)

    Dave, Vivek S; Gupta, Deepak; Yu, Monica; Nguyen, Phuong; Varghese Gupta, Sheeba

    2017-02-01

    The Biopharmaceutics Classification System (BCS) classifies pharmaceutical compounds based on their aqueous solubility and intestinal permeability. The BCS Class III compounds are hydrophilic molecules (high aqueous solubility) with low permeability across the biological membranes. While these compounds are pharmacologically effective, poor absorption due to low permeability becomes the rate-limiting step in achieving adequate bioavailability. Several approaches have been explored and utilized for improving the permeability profiles of these compounds. The approaches include traditional methods such as prodrugs, permeation enhancers, ion-pairing, etc., as well as relatively modern approaches such as nanoencapsulation and nanosizing. The most recent approaches include a combination/hybridization of one or more traditional approaches to improve drug permeability. While some of these approaches have been extremely successful, i.e. drug products utilizing the approach have progressed through the USFDA approval for marketing; others require further investigation to be applicable. This article discusses the commonly studied approaches for improving the permeability of BCS Class III compounds.

  8. Salt-saturated concrete strength and permeability

    International Nuclear Information System (INIS)

    Pfeifle, T.W.; Hansen, F.D.; Knowles, M.K.

    1996-01-01

    Laboratory-scale experiments applicable to the use of salt-saturated concrete as a seal material for a transuranic waste repository have been completed. Nitrogen gas permeability measurements were made using a flexible-wall permeameter, a confining pressure of 1 MPa, and gas pressure gradients ranging from 0.3 MPa to 0.75 MPa. Results show that salt-saturated concrete has very low intrinsic permeability with values ranging from 9.4 x 10 -22 m 2 to 9.7 x 10 -17 m 2 . Strength and deformation characteristics were investigated under conditions of triaxial compression with confining pressures ranging from 0 to 15 MPa using either axial strain-rate or axial stress-rate control and show that the failure strength of concrete increases with confining pressure which can be adequately described through pressure-sensitive failure criteria. Axial, radial, and volumetric strains were also measured during each test and these data were used to determine elastic properties. Experimental results are applicable in the design and analysis of scale-related functions and apply to other concrete structures subjected to compressive loadings such as dams and prestressed structural members

  9. METHODOLOGY FOR CALCULATION OF HORIZONTAL WATER PERMEABILITY COEFFICIENT IN SOIL CAPILLARY BORDER

    Directory of Open Access Journals (Sweden)

    E. I. Michnevich

    2011-01-01

    Full Text Available The paper shows that for overall estimation of soil water permeability it is necessary to know a horizontal water permeability value of a soil capillary border in addition to coefficients of filtration and permeability. Relations allowing to determine soil permeability in the area of incomplete saturation, are given in the paper. For a fully developed capillary border some calculation formulae have been obtained in the form of algebraic polynomial versus soil grading (grain composition. These formulae allow to make more accurate calculations while designing and operating  reclamation works.

  10. Permeability of highly compacted bentonite

    International Nuclear Information System (INIS)

    Pusch, R.

    1980-12-01

    The object of the study was the water flow through the bentonite which is caused by hydraulic gradients. The study comprised laboratory tests and theoretical considerations. It was found that high bulk densities reduced the permeability to very low values. It was concluded that practically impervious conditions prevail when the gradients are low. Thus with a regional gradient of 10 -2 and a premeability of 10 -13 m/s the flow rate will not be higher than approximately 1 mm in 30 000 years. (G.B.)

  11. Relationship between non-standard work arrangements and work-related accident absence in Belgium.

    Science.gov (United States)

    Alali, Hanan; Braeckman, Lutgart; Van Hecke, Tanja; De Clercq, Bart; Janssens, Heidi; Wahab, Magd Abdel

    2017-03-28

    The main objective of this study is to examine the relationship between indicators of non-standard work arrangements, including precarious contract, long working hours, multiple jobs, shift work, and work-related accident absence, using a representative Belgian sample and considering several socio-demographic and work characteristics. This study was based on the data of the fifth European Working Conditions Survey (EWCS). For the analysis, the sample was restricted to 3343 respondents from Belgium who were all employed workers. The associations between non-standard work arrangements and work-related accident absence were studied with multivariate logistic regression modeling techniques while adjusting for several confounders. During the last 12 months, about 11.7% of workers were absent from work because of work-related accident. A multivariate regression model showed an increased injury risk for those performing shift work (OR 1.546, 95% CI 1.074-2.224). The relationship between contract type and occupational injuries was not significant (OR 1.163, 95% CI 0.739-1.831). Furthermore, no statistically significant differences were observed for those performing long working hours (OR 1.217, 95% CI 0.638-2.321) and those performing multiple jobs (OR 1.361, 95% CI 0.827-2.240) in relation to work-related accident absence. Those who rated their health as bad, low educated workers, workers from the construction sector, and those exposed to biomechanical exposure (BM) were more frequent victims of work-related accident absence. No significant gender difference was observed. Indicators of non-standard work arrangements under this study, except shift work, were not significantly associated with work-related accident absence. To reduce the burden of occupational injuries, not only risk reduction strategies and interventions are needed but also policy efforts are to be undertaken to limit shift work. In general, preventive measures and more training on the job are needed to

  12. Determination of hydrogen permeability in commercial and modified superalloys

    Science.gov (United States)

    Bhattacharyya, S.; Peterman, W.

    1983-01-01

    The results of hydrogen permeability measurements on several iron- and cobalt-base alloys as well as on two long-ranged ordered alloys over the range of 705 to 870 C (1300 to 1600 F) are summarized. The test alloys included wrought alloys N-155, IN 800, A-286, 19-9DL, and 19-9DL modifications with aluminum, niobium, and misch metal. In addition, XF-818, CRM-6D, SA-F11, and HS-31 were evaluated. Two wrought long-range ordered alloys, Ni3Al and (Fe,Ni)3(V,Al) were also evaluated. All tests were conducted at 20.7 MPa pressure in either pure and/or 1% CO2-doped H2 for test periods as long as 133 h. Detailed analyses were conducted to determine the relative permeability rankings of these alloys and the effect of doping, exit surface oxidation, specimen design variations, and test duration on permeability coefficient, and permeation activation energies were determined. The two long-range ordered alloys had the lowest permeability coefficients in pure H2 when compared with the eight commercial alloys and their modifications. With CO2 doping, significant decrease in permeability was observed in commercial alloys--no doped tests were conducted with the long-range ordered alloys.

  13. Modeling stress/strain-dependent permeability changes for deep geoenergy applications

    Science.gov (United States)

    Rinaldi, Antonio Pio; Rutqvist, Jonny

    2016-04-01

    Rock permeability is a key parameter in deep geoenergy systems. Stress and strain changes induced at depth by fluid injection or extraction may substantially alter the rock permeability in an irreversible way. With regard to the geoenergies, some applications require the permeability to be enhanced to improve productivity. The rock permeability is generally enhanced by shearing process of faults and fractures (e.g. hydroshearing for Enhanced and Deep Geothermal Systems), or the creation of new fractures (e.g. hydrofracturing for shale gas). However, such processes may, at the same time, produce seismicity that can be felt by the local population. Moreover, the increased permeability due to fault reactivation may pose at risk the sealing capacity of a storage site (e.g. carbon sequestration or nuclear waste disposal), providing then a preferential pathway for the stored fluids to escape at shallow depth. In this work we present a review of some recent applications aimed at understanding the coupling between stress (or strain) and permeability. Examples of geoenergy applications include both EGS and CO2 sequestration. To investigate both "wanted" and "unwanted" effects, THM simulations have been carried out with the TOUGH-FLAC simulator. Our studies include constitutive equations relating the permeability to mean effective stress, effective normal stress, volumetric strain, as well as accounting for permeability variation as related to fault/fracture reactivation. Results show that the geomechanical effects have a large role in changing the permeability, hence affecting fluids leakage, reservoir enhancement, as well as the induced seismicity.

  14. Relations between different types of jealousy and self and partner perceptions of relationship quality

    NARCIS (Netherlands)

    Barelds, D.P.H.; Barelds-Dijkstra, P.

    2007-01-01

    The present paper examines the relationships between relationship quality and three different types of jealousy, including both partners' levels of jealousy and perceptions of relationship quality. It was expected that jealousy in response to a direct threat to the relationship-that is, reactive

  15. The Relations between Decision Making in Social Relationships and Decision Making Styles

    Science.gov (United States)

    Sari, Enver

    2008-01-01

    The research reported in this paper aimed to examine the relationships between decisiveness in social relationships, and the decision-making styles of a group of university students and to investigate the contributions of decision-making styles in predicting decisiveness in social relationship (conflict resolution, social relationship selection…

  16. Relative relationships of general shame and body shame with body dysmorphic phenomenology and psychosocial outcomes.

    Science.gov (United States)

    Weingarden, Hilary; Renshaw, Keith D; Davidson, Eliza; Wilhelm, Sabine

    2017-07-01

    Body Dysmorphic Disorder (BDD) is characterized by a preoccupation with a perceived flaw in appearance and repetitive avoidance behaviors. BDD involves severe psychosocial outcomes (e.g., depression, suicidality, functional impairment). Identifying correlates of BDD symptoms and outcomes can inform treatment. Shame, a painful emotion felt in response to critical self-judgment, may be one key correlate. However, research on shame in BDD is scarce and previous studies have not distinguished general shame from body shame. This study examines the relative relationships between body shame and general shame with body dysmorphic phenomenology and psychosocial outcomes. Participants ( N = 184) were recruited online via BDD organizations and completed a survey. Path analysis was used to examine associations between body and general shame with 1) body dysmorphic phenomenology and 2) depression severity, suicide risk, and functional impairment. Both types of shame were differentially related to outcomes. Body shame was more strongly related to phenomenology, whereas general shame was more strongly related to psychosocial outcomes. Thus, it may be important for BDD treatment to focus on reducing both general and body shame. Further research should evaluate whether current treatments adequately address and reduce general and body shame, and whether addressing shame promotes better treatment outcomes.

  17. The relationship between lifestyle, occupational health, and work-related factors with presenteeism amongst general practitioners.

    Science.gov (United States)

    Pit, Sabrina Winona; Hansen, Vibeke

    2016-01-01

    There is evidence that general practitioners (GPs) are more likely to exhibit sickness presenteeism than other health professional groups or other high-income earners and less likely to take sick leave. This study aims to examine the relationship between lifestyle, occupational health, and work-related factors with presenteeism amongst GPs. A cross-sectional study was conducted amongst GPs in 2011. Logistic regression was used to determine crude and adjusted odds ratios between lifestyle, occupational health, and work-related factors with presenteeism. Whilst adjusting for age and gender, exercising 1 to 3 times a week (odds ratio [OR] = 4.88), not having a good work-life balance (OR = 4.2), work-related sleep problems (OR = 2.55), moderate psychological distress (OR = 3.94), and poor or fair health (OR = 6.22) were associated with presenteeism. Increased burnout and reduced job satisfaction and workability due to the physical demands of the job were also associated with presenteeism. In conclusion, presenteeism amongst GPs can be addressed by implementing interventions in relation to physical activity, stress reduction, and sleep hygiene and improving work-life balance and the physical demands of the job.

  18. The Relationship of Peer Relations of University Students with Several Factors

    Directory of Open Access Journals (Sweden)

    Erdoğan TOZOĞLU

    2015-12-01

    Full Text Available It is only possible through positive relationships between communicating individuals in social and education life to experience a high level information sharing and cooperation. It is known that the level of such an interaction among peer groups will be higher than that seen among other individual groups. Objective of the present study was to determine the variables which can affect the level of peer relations among university students and the effect levels of peer relations in education process and social life. It was found from the results that there is a significant difference between mean scores of the subscales of peer relations when considered the variables of gender, individual monthly income, family structure, performing sportive activities, time spent on sport weekly and the reason for performing sportive activities. No significant difference was found between the groups for the types of sportive activities. The level of peer relation among the students performing sportive activities was found to be higher than those who are not engaged in any kinds of sport activities.

  19. Relative Age Effect: Relationship between Anthropometric and Fitness Skills in Youth Soccer

    Directory of Open Access Journals (Sweden)

    Aristotelis GIOLDASIS

    2015-12-01

    Full Text Available The aim of the study was to determine the relationship between anthropometric and fitness skills in youth soccer players according to their related age. The existence of relative age effect was also examined. Anthropometric as well fitness variables such as height, weight, BMI, body mass, flexibility, balance, reaction time, jumping ability, and endurance of the lower limb were assessed in 347 amateur young players. Participants’ age ranged from 9 to 16 (M= 12.43, SD= 2.17. Analyses of variance indicated many significant differences among players of different birth quartile (from P< .001 to P< .05 for all the skills that were examined. The chi square test that was conducted to assess the distribution of players, showed that for all four different age groups no statistically significant difference was found regarding the birth quartile of players. In countries that training groups include 2 different age categories, anthropometric and fitness differences because of relative age effect are heightened. However, physical and physiological variables are inaccurate in predicting later success of players. Thus talent identification systems should provide equal opportunities for talented but related younger players. It is suggested an on-going talent identification using a multidimensional evaluation form including technical, physiological, physical, tactical, and psychological parameters.

  20. [Relationship between PMI and relative expression of myocardial various RNAs in rats died of different causes].

    Science.gov (United States)

    Lü, Ye-Hui; Zhang, Heng; Pan, Hui; Ma, Kai-Jun; Li, Wen-Can; Chen, Wen-Feng; Jiang, Jie-Qing'; Xue, Ai-Min; Zhang, Ping; Wang, Hui-Jun; Chen, Long

    2014-02-01

    To observe the changes of relative expression of myocardial various RNAs in rats died of different causes and their relationship with PMI. The rat models were established in which the rats were sacrificed by broken neck, asphyxia, and hemorrhagic shock. Total RNAs were extracted from myocardium. The quantitative real time PCR was used to calculate threshold cycle values of RNAs including glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-actin, inducible nitric oxide synthase (iNOS), hypoxia-inducible factor-1 (HIF-1), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and U6 small nuclear RNA (U6 snRNA) and to study the changes of the relative expressions of various indexes with PMI. U6 snRNA with stable expression level could be used as appropriate internal control. In the early PMI, the relative expression of GAPDH, HIF-1, iNOS, TNF-alpha, and IL-6 more characteristically increased in groups of asphyxia and hemorrhagic shock than in group of broken neck, but the quantity of beta-actin decreased in all groups. In the late PMI, all the relative expressions significantly declined in correlation with the degradation of RNA. The characteristic changes of each RNA expression can be used as references to estimate PMI in deaths by different causes.

  1. Social impressions while drinking account for the relationship between alcohol-related problems and social anxiety.

    Science.gov (United States)

    Buckner, Julia D; Matthews, Russell A

    2012-04-01

    Individuals with elevated social anxiety appear particularly vulnerable to experiencing alcohol-related problems; yet we know little about factors that may account for this relationship. One possibility is that socially anxious individuals hold beliefs about the impressions they make on others while drinking and these beliefs play an important role in their drinking behaviors. The present study used exploratory factor analysis among participants with clinically elevated social anxiety (n=166) to develop a measure, the Social Impressions while Drinking Scale (SIDS), to assess beliefs regarding others' impressions of drinking behaviors that may be particularly relevant to socially anxious individuals. A valuations scale was also developed to assess the importance of each belief. Empirically-derived subscales were identified with adequate reliability. Among socially anxious participants, the Gregarious and Sexual Facilitation subscales were uniquely related to drinking problems and frequency respectively. Individuals with clinically meaningful social anxiety achieved higher scores on all SIDS subscales compared to those with lower social anxiety (n=166). Several SIDS scales mediated the relations between social anxiety group status and drinking problems (Interaction Fears, Observation Fears, Aggression, Gregariousness). Results highlight the importance of examining beliefs specific to high-risk populations in assessing their alcohol-related behaviors. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Developmental and ethnic issues experienced by emerging adult African American women related to developing a mature love relationship.

    Science.gov (United States)

    Tyson, Sheryl Y

    2012-01-01

    This qualitative study explored perspectives of emerging adult African American women on the development of mature love relationships. Inductive analysis of focus group interviews, conducted with a purposive sample of 31 African American women, yielded themes related to relationship goals and characteristics, and interpersonal and societal challenges to finding the right partner and developing a mature love relationship. Core categories that emerged from analysis of the discussions were (1) age and relationship goal differences within the emerging adult group, (2) mature love relationship goals and characteristics, (3) interpersonal obstacles to finding the right partner, and (4) societal obstacles to finding the right partner. Two approaches-black womanist/feminist thought (Collins, 2000 ; Walker, 1983 ) and relationship maturity theory (Paul & White, 1990 )-were then combined to explain the influence of historic and contemporary interpersonal and societal factors on developmental and ethnic issues that challenge positive gender identity formation, hasten intimacy maturity, and hinder the development of mature love relationships among emerging adult African American women. For these women, premature responsibility, especially early caregiver burden, was related to the early development of intimacy capacity and the desire for a mature love relationship, to be protected, and to have someone to help carry the load. Interracial dating, negative stereotypic images of African American women, and even positive images of enduring black love relationships posed difficult challenges to positive identity formation and intimacy maturity. A primary challenge was to counteract negative stereotypic images, so that they could develop their own self-identities as women and as relationship partners.

  3. Reactive, anxious and possessive forms of jealousy and their relation to relationship quality among heterosexuals and homosexuals.

    Science.gov (United States)

    Barelds, Dick P H; Dijkstra, Pieternel

    2006-01-01

    The present study examined the relationship between relational quality and three different types of jealousy-reactive, anxious and possessive jealousy. The sample consisted of 76 gay men, 79 lesbians, 70 heterosexual women and 70 heterosexual men. Findings show that different types of jealousy affect relationship quality differently and do so differently for homosexuals and heterosexuals. Among heterosexuals and especially gay men--but not among lesbians--anxious jealousy was negatively related to relationship quality. In contrast, among heterosexuals--but not among gay men or lesbians--reactive jealousy was positively related to relationship quality. The present study shows that distinguishing between different types of jealousy is necessary to entangle the diverse effects of jealousy on the quality of homosexual and heterosexual relationships.

  4. Permeability and dispersivity of variable-aperture fracture systems

    International Nuclear Information System (INIS)

    Tsang, Y.W.; Tsang, C.F.

    1990-01-01

    A number of recent experiments have pointed out the need of including the effects of aperture variation within each fracture in predicting flow and transport properties of fractured media. This paper introduces a new approach in which medium properties, such as the permeability to flow and dispersivity in tracer transport, are correlated to only three statistical parameters describing the fracture aperture probability distribution and the aperture spatial correlation. We demonstrate how saturated permeability and relative permeabilities for flow, as well as dispersion for solute transport in fractures may be calculated. We are in the process of examining the applicability of these concepts to field problems. Results from the evaluation and analysis of the recent Stripa-3D field data are presented. 13 refs., 10 figs

  5. An intelligent detecting system for permeability prediction of MBR.

    Science.gov (United States)

    Han, Honggui; Zhang, Shuo; Qiao, Junfei; Wang, Xiaoshuang

    2018-01-01

    The membrane bioreactor (MBR) has been widely used to purify wastewater in wastewater treatment plants. However, a critical difficulty of the MBR is membrane fouling. To reduce membrane fouling, in this work, an intelligent detecting system is developed to evaluate the performance of MBR by predicting the membrane permeability. This intelligent detecting system consists of two main parts. First, a soft computing method, based on the partial least squares method and the recurrent fuzzy neural network, is designed to find the nonlinear relations between the membrane permeability and the other variables. Second, a complete new platform connecting the sensors and the software is built, in order to enable the intelligent detecting system to handle complex algorithms. Finally, the simulation and experimental results demonstrate the reliability and effectiveness of the proposed intelligent detecting system, underlying the potential of this system for the online membrane permeability for detecting membrane fouling of MBR.

  6. The relationship between proxy reported health-related quality of life and parental distress: gender differences.

    Science.gov (United States)

    Davis, E; Davies, B; Waters, E; Priest, N

    2008-11-01

    Although primary caregiver proxy reports of health-related quality of life (HRQOL) are often used for healthcare decision making when child self-reports are unable to be collected (because of a variety of reasons such as child illness, disability or age), we have little understanding of the correlates of parent-proxy reports. The aim of this study was to examine the relationship between parental depression and parent-proxy reported QOL for primary caregivers (mothers and fathers), using a multidimensional HRQOL instrument. It was hypothesized that maternal depression would be negatively correlated with maternal reported HRQOL, but that paternal depression would not be correlated with paternal reported HRQOL. Data were from parents of children aged 4-5 years (n = 4983) involved in the Longitudinal Study of Australian Children. A questionnaire assessing parental depression (Kessler-6) and proxy reported HRQOL (Pediatric Quality of Life Inventory) was completed by the primary caregiver. For maternal primary caregivers, maternal depression was negatively correlated with all domains of maternal proxy reports of HRQOL (r = -0.24 to r = -0.36). For paternal primary caregivers, there was no relationship between paternal depression and paternal proxy reports of HRQOL. Multiple regression analyses demonstrated that maternal depression was a significant predictor of total HRQOL, accounting for 12% of the variance. For paternal mental health, depression did not predict parent-proxy reported total HRQOL. These results highlight the importance of assessing maternal mental health when measuring proxy reported QOL. Further research is needed in this area to examine the relationship between parental depression and proxy reported HRQOL (including both mothers and fathers, where possible), as well as child self-reported HRQOL.

  7. Relationships between Microbial Activities and Subduction-related Outgassing and Volatile Flux at Aleutian Arc Volcanoes

    Science.gov (United States)

    Miller, H.; Lopez, T. M.; Fischer, T. P.; Schrenk, M. O.

    2016-12-01

    Subduction-related processes, including the movement and alteration of carbon compounds, are an important component of global geochemical cycles. Actively degassing volcanoes of the Aleutian Island arc offer interesting opportunities to not only characterize the composition and abundance of volatiles, but also to identify the origin of the discharging gases (e.g. mantle, organic matter, or carbonates). Taking this approach a step further, microbial activities in and around volcanic fumarole areas may impact the composition and flux of reduced volcanic gases, either through their modification or their assimilation into fixed biomass. Microbiological studies of these systems can be used to develop predictive models to complement those based upon geochemical data while providing greater understanding of the causal relationships between microbial populations and their environment, and ultimately refine estimates of volcanic outgassing. Coupled fumarole soil and gas samples were collected from several Aleutian Island volcanoes in 2015 (Gareloi, Kanaga, Kiska, Little Sitkin) and 2016 (Okmok, Resheschnoi). DNA was extracted from the soil and used to describe microbial community composition, while gas samples were analyzed through chromatography and mass spectrometry. Preliminary data suggests a relationship between the abundance of specific groups of prokaryotes known to metabolize reduced gases, such as sulfur-oxidizers and methanotrophs, and the abundances of the degassing volatiles, including sulfur dioxide and methane. Ongoing studies aimed at investigating the relationship between the genomic composition of the fumarolic microbial community and the physical and chemical properties of the soil (i.e. mineralogy, bulk geochemistry, nutrient concentration, gas flux, and environmental measurements) are underway. These data will be used to evaluate the potential for microbial communities to remove volcanic carbon and store it as biomass, or to modify the volatile carbon

  8. Age-Related Relationships between Innate Immunity and Plasma Carotenoids in an Obligate Avian Scavenger.

    Science.gov (United States)

    López-Rull, Isabel; Hornero-Méndez, Dámaso; Frías, Óscar; Blanco, Guillermo

    2015-01-01

    Variation in immunity is influenced by allocation trade-offs that are expected to change between age-classes as a result of the different environmental and physiological conditions that individuals encounter over their lifetime. One such trade-off occurs with carotenoids, which must be acquired with food and are involved in a variety of physiological functions. Nonetheless, relationships between immunity and carotenoids in species where these micronutrients are scarce due to diet are poorly studied. Among birds, vultures show the lowest concentrations of plasma carotenoids due to a diet based on carrion. Here, we investigated variations in the relationships between innate immunity (hemagglutination by natural antibodies and hemolysis by complement proteins), pathogen infection and plasma carotenoids in nestling and adult griffon vultures (Gyps fulvus) in the wild. Nestlings showed lower hemolysis, higher total carotenoid concentration and higher pathogen infection than adults. Hemolysis was negatively related to carotenoid concentration only in nestlings. A differential carotenoid allocation to immunity due to the incomplete development of the immune system of nestlings compared with adults is suggested linked to, or regardless of, potential differences in parasite infection, which requires experimental testing. We also found that individuals with more severe pathogen infections showed lower hemagglutination than those with a lower intensity infection irrespective of their age and carotenoid level. These results are consistent with the idea that intraspecific relationships between innate immunity and carotenoids may change across ontogeny, even in species lacking carotenoid-based coloration. Thus, even low concentrations of plasma carotenoids due to a scavenger diet can be essential to the development and activation of the immune system in growing birds.

  9. Does it take a village to raise a child?: The buffering effect of relationships with relatives for parental life satisfaction

    Directory of Open Access Journals (Sweden)

    Małgorzata Mikucka

    2016-06-01

    Full Text Available Background: Strong relationships with relatives may alleviate the consequences of stressful experiences,but the evidence documenting such 'buffering effect' during parenthood is scarce. Objective: This paper investigated the buffering effect of relationships with relatives during parenthoodin Switzerland. We tested whether relationships with relatives (network size, frequencyof contact, and availability of practical and emotional support were activated inresponse to parenthood, and if people who had stronger relationships with their relativesexperienced more positive trajectories of life satisfaction during parenthood. Methods: We used Swiss Household Panel data for the years 2000-2011, and fixed effect regressionmodels. Results: The birth of a first child was associated with an increase in mothers' contact with nonresidentrelatives. Moreover, parents with at least two children who had better accessto support from relatives experienced more increase and less decline in life satisfactionduring parenthood than parents who had less access to relatives' support. Conclusions: Our study suggests that the support of relatives is a resource for parents having twoor more children and that it improves the experience of parenthood even in a relativelywealthy society. Contribution: This is the first paper which demonstrates that relationships with relatives are a source of heterogeneity of the effect of parenthood on life satisfaction. Moreover, it shows that weak relationships with relatives may lower life satisfaction of parents and limit fertility, especially at higher parities.

  10. Production-log base model for carbonate permeability distribution and steam flood optimization

    Energy Technology Data Exchange (ETDEWEB)

    Ahamed, S.F.; Choudhry, M.A.; Abdulbaqi, J.B. [Kuwait Gulf Oil Co. (Kuwait)

    2008-10-15

    This paper presented a model for the effective management of primary and thermal oil recovery operations in the Wafra Field in Kuwait, where a small huff and puff project was carried out in 1998 to determine if steam injection was a feasible recovery option for the field. The Eocene heavy oil reservoirs of the Wafra Field are carbonate rock admixtures with gypsum and anhydrite. They are the shallowest of the field's productive horizons and exhibit a high degree of fluid flow heterogeneity. The assessment of vertical and lateral permeability variation is a key factor for success of the reservoir development plan. Steam injection began in 2006 in a small scale test (SST) to determine if the innovative technology could produce steam from effluent water and to test the viability of steam injection in carbonate reservoirs. Following the success of the SST, a large scale pilot (LSP) is schedule to start in 2009. It can be used for completion strategies of injectors and producers in steam injection. The model showed that the productivity of the Eocene wells could be correlated with common available logs to develop a log based-permeability model. A series of cross plots for the perforated intervals of high and low productivity wells were constructed to develop a relationship between well productivity and location of log parameters on the plots. A relationship between rock quality, productivity and conventional log parameters was established. It was concluded that the vertical permeability and interwell continuity in the Eocene wells can be used to optimize new well placement for horizontal and vertical infill drilling. The model is also an effective tool to predict the steam injectivity profile to understand the anomalies related to temperature-depth distribution. The model can be used to improve the efficiency of formation heating by optimizing the steam flood process and steam pattern well completion. 16 refs.

  11. Teacher and observer views on student-teacher relationships: convergence across kindergarten and relations with student engagement

    NARCIS (Netherlands)

    dr Doumen, S.; Koomen, H.M.Y.; Buyse, E.; Wouters, S.; Verschueren, K.

    2012-01-01

    Most studies regarding the role of teacher-child relationships for children's early school adjustment use only teacher ratings of relationship quality. The current study examines (a) the agreement between teacher and observer ratings, (b) whether similar patterns of relations with behavioral

  12. Gap junction protein connexin43 exacerbates lung vascular permeability.

    Directory of Open Access Journals (Sweden)

    James J O'Donnell

    Full Text Available Increased vascular permeability causes pulmonary edema that impairs arterial oxygenation and thus contributes to morbidity and mortality associated with Acute Respiratory Distress Syndrome and sepsis. Although components of intercellular adhesive and tight junctions are critical for maintaining the endothelial barrier, there has been limited study of the roles of gap junctions and their component proteins (connexins. Since connexins can modulate inflammatory signaling in other systems, we hypothesized that connexins may also regulate pulmonary endothelial permeability. The relationships between connexins and the permeability response to inflammatory stimuli were studied in cultured human pulmonary endothelial cells. Prolonged treatment with thrombin, lipopolysaccharide, or pathological cyclic stretch increased levels of mRNA and protein for the major connexin, connexin43 (Cx43. Thrombin and lipopolysaccharide both increased intercellular communication assayed by transfer of microinjected Lucifer yellow. Although thrombin decreased transendothelial resistance in these cells, the response was attenuated by pretreatment with the connexin inhibitor carbenoxolone. Additionally, the decreases of transendothelial resistance produced by either thrombin or lipopolysaccharide were attenuated by reducing Cx43 expression by siRNA knockdown. Both carbenoxolone and Cx43 knockdown also abrogated thrombin-induced phosphorylation of myosin light chain. Taken together, these data suggest that increased lung vascular permeability induced by inflammatory conditions may be amplified via increased expression of Cx43 and intercellular communication among pulmonary endothelial cells.

  13. Ways of giving benefits in marriage: norm use, relationship satisfaction, and attachment-related variability.

    Science.gov (United States)

    Clark, Margaret S; Lemay, Edward P; Graham, Steven M; Pataki, Sherri P; Finkel, Eli J

    2010-07-01

    Couples reported on bases for giving support and on relationship satisfaction just prior to and approximately 2 years into marriage. Overall, a need-based, noncontingent (communal) norm was seen as ideal and was followed, and greater use of this norm was linked to higher relationship satisfaction. An exchange norm was seen as not ideal and was followed significantly less frequently than was a communal norm; by 2 years into marriage, greater use of an exchange norm was linked with lower satisfaction. Insecure attachment predicted greater adherence to an exchange norm. Idealization of and adherence to a communal norm dropped slightly across time. As idealization of a communal norm and own use and partner use of a communal norm decreased, people high in avoidance increased their use of an exchange norm, whereas people low in avoidance decreased their use of an exchange norm. Anxious individuals evidenced tighter links between norm use and marital satisfaction relative to nonanxious individuals. Overall, a picture of people valuing a communal norm and striving toward adherence to a communal norm emerged, with secure individuals doing so with more success and equanimity across time than insecure individuals.

  14. Evolution of the turtle bauplan: the topological relationship of the scapula relative to the ribcage.

    Science.gov (United States)

    Lyson, Tyler R; Joyce, Walter G

    2012-12-23

    The turtle shell and the relationship of the shoulder girdle inside or 'deep' to the ribcage have puzzled neontologists and developmental biologists for more than a century. Recent developmental and fossil data indicate that the shoulder girdle indeed lies inside the shell, but anterior to the ribcage. Developmental biologists compare this orientation to that found in the model organisms mice and chickens, whose scapula lies laterally on top of the ribcage. We analyse the topological relationship of the shoulder girdle relative to the ribcage within a broader phylogenetic context and determine that the condition found in turtles is also found in amphibians, monotreme mammals and lepidosaurs. A vertical scapula anterior to the thoracic ribcage is therefore inferred to be the basal amniote condition and indicates that the condition found in therian mammals and archosaurs (which includes both developmental model organisms: chickens and mice) is derived and not appropriate for studying the developmental origin of the turtle shell. Instead, among amniotes, either monotreme mammals or lepidosaurs should be used.

  15. Different Methods of Predicting Permeability in Shale

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Krogsbøll, Anette

    by two to five orders of magnitudes at lower vertical effective stress below 40 MPa as the content of clay minerals increases causing heterogeneity in shale material. Indirect permeability from consolidation can give maximum and minimum values of shale permeability needed in simulating fluid flow......Permeability is often very difficult to measure or predict in shale lithology. In this work we are determining shale permeability from consolidation tests data using Wissa et al., (1971) approach and comparing the results with predicted permeability from Kozeny’s model. Core and cuttings materials...... effective stress to 9 μD at high vertical effective stress of 100 MPa. The indirect permeability calculated from consolidation tests falls in the same magnitude at higher vertical effective stress, above 40 MPa, as that of the Kozeny model for shale samples with high non-clay content ≥ 70% but are higher...

  16. Influence of effective stress and dry density on the permeability of municipal solid waste.

    Science.gov (United States)

    Zhang, Zhenying; Wang, Yingfeng; Xu, Hui; Fang, Yuehua; Wu, Dazhi

    2018-05-01

    A landfill is one of the main sites for disposal of municipal solid waste and the current landfill disposal system faces several problems. For instance, excessive leachate water is an important factor leading to landfill instability. Understanding the permeability characteristics of municipal solid waste is a relevant topic in the field of environmental geotechnical engineering. In this paper, the current research progress on permeability characteristics of municipal solid waste is discussed. A review of recent studies indicates that the research in this field is divided into two categories based on the experimental method employed: field tests and laboratory tests. This paper summarizes test methods, landfill locations, waste ages, dry densities and permeability coefficients across different studies that focus on permeability characteristics. Additionally, an experimental study on compressibility and permeability characteristics of fresh municipal solid waste under different effective stresses and compression times was carried out. Moreover, the relationships between the permeability coefficient and effective stress as well as dry density were obtained and a permeability prediction model was established. Finally, the experimental results from the existing literature and this paper were compared and the effects of effective stress and dry density on the permeability characteristics of municipal solid waste were summarized. This study provides the basis for analysis of leachate production in a landfill.

  17. Corneal and conjunctival drug permeability: Systematic comparison and pharmacokinetic impact in the eye.

    Science.gov (United States)

    Ramsay, Eva; Del Amo, Eva M; Toropainen, Elisa; Tengvall-Unadike, Unni; Ranta, Veli-Pekka; Urtti, Arto; Ruponen, Marika

    2018-07-01

    On the surface of the eye, both the cornea and conjunctiva are restricting ocular absorption of topically applied drugs, but barrier contributions of these two membranes have not been systemically compared. Herein, we studied permeability of 32 small molecular drug compounds across an isolated porcine cornea and built a quantitative structure-property relationship (QSPR) model for the permeability. Corneal drug permeability (data obtained for 25 drug molecules) showed a 52-fold range in permeability (0.09-4.70 × 10 -6  cm/s) and the most important molecular descriptors in predicting the permeability were hydrogen bond donor, polar surface area and halogen ratio. Corneal permeability values were compared to their conjunctival drug permeability values. Ocular drug bioavailability and systemic absorption via conjunctiva were predicted for this drug set with pharmacokinetic calculations. Drug bioavailability in the aqueous humour was simulated to be drug across the conjunctiva to the blood circulation restricts significantly ocular drug bioavailability and, therefore, ocular absorption does not increase proportionally with the increasing corneal drug permeability. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Some additional results on the directional relationships between forces and accelerations in special relativity

    International Nuclear Information System (INIS)

    Gonzales-Diaz, P.F.

    1979-01-01

    Some directional relationships between forces and accelerations in special relativity have been studied by considering the most general case of a body having x, y and z components of velocity, which is acted upon by a force with nonzero components. The behaviour of a sub(y)/ a sub(x) and a sub(y)/ a sub(z) vs. velocity for different force component ratios is studied in the general situation in which vsub(x) different from Vsub(y)different from vsub(z). It is shown that one or two, suddently varying, negative acceleration components can result for the body at sufficiently high velocities, and an explanation is given

  19. The influence of age on lung epithelial permeability

    International Nuclear Information System (INIS)

    Yang Minfu; Wang Daoyu; Liu Xiujie; He Zuoxiang; Wang Yuetao; Wang Shiwen

    2007-01-01

    Objective: The pulmonary clearance rate of aerosolized 99 Tc m -DTPA is a sensitive index for measurement of lung epithelial permeability (LEP). It is well established that LEP increases in some pathological conditions. However, little is known about the influence of age on LEP. Accordingly, the aim of this study was to evaluate the relationship between age and LEP in healthy nonsmokers. Methods: Seventy-nine healthy nonsmokers underwent 99 Tc m -DTPA inhalation imaging and pulmonary clearance index (k) was calculated. The following analyses were done: (1) To compare the difference of k values between aged (≥ 65 years) and non-aged ( 0 + b 1 x + b 2 x 2 + b 3 x 3 , y symbolized k values and x symbolized age). Conclusions: The data of LEP at different age groups showed negative correlation of LEP and age in non-smokers. This data might play an age-related reference data in investigating senescence and lung disease in non-smokers. (authors)

  20. Study on relationship between apoptosis-related genes and radiosensitivity of esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Li Huixiang; Wang Yaohe; Shi Yonggang; Gao Dongling; Zhang Yunhan

    2000-01-01

    Objective: To observing the relationship between apoptosis-related genes bcl-2,c-myc, p53 and the radiosensitivity of esophageal squamous cell carcinoma. Methods: The expression levels of bcl-2, c-myc and p53 genes in 57 biopsy samples from patients of esophageal squamous cell carcinoma were detected with the LSAB immunohistochemistry method. All the patients were treated with radiotherapy. The radiotherapeutic effect in these patients was observed and the relation between gene expression and radiosensitivity was analyzed. Results: Compared with the bcl-2-negative group, the radiosensitivity of bcl-2-positive one was lower(P<0.01). The radiosensitivity of p53-positive group was slightly lower than that of the p53-negative one (P<0.05). The c-myc protein expression was not related to radiosensitivity. Conclusion: Detection and comprehensive analysis of bcl-2, c-myc and p53 protein expressions are useful in forecasting the radiotherapeutic effect on squamous cell carcinoma of esophagus

  1. On the relationship between convex bodies related to correlation experiments with dichotomic observables

    Energy Technology Data Exchange (ETDEWEB)

    Avis, David [School of Computer Science, McGill University, 3480 University, Montreal, Quebec, H3A 2A7 (Canada); Imai, Hiroshi [Department of Computer Science, Graduate School of Information Science and Technology, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Ito, Tsuyoshi [Department of Computer Science, Graduate School of Information Science and Technology, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2006-09-08

    In this paper we explore further the connections between convex bodies related to quantum correlation experiments with dichotomic variables and related bodies studied in combinatorial optimization, especially cut polyhedra. Such a relationship was established in Avis et al (2005 J. Phys. A: Math. Gen. 38 10971-87) with respect to Bell inequalities. We show that several well-known bodies related to cut polyhedra are equivalent to bodies such as those defined by Tsirelson (1993 Hadronic J. Suppl. 8 329-45) to represent hidden deterministic behaviours, quantum behaviours and no-signalling behaviours. Among other things, our results allow a unique representation of these bodies, give a necessary condition for vertices of the no-signalling polytope, and give a method for bounding the quantum violation of Bell inequalities by means of a body that contains the set of quantum behaviours. Optimization over this latter body may be performed efficiently by semidefinite programming. In the second part of the paper we apply these results to the study of classical correlation functions. We provide a complete list of tight inequalities for the two party case with (m, n) dichotomic observables when m = 4, n = 4 and when min{l_brace}m, n{r_brace} {<=} 3, and give a new general family of correlation inequalities.

  2. Relationships of cognitive load on eating and weight-related behaviors of young adults.

    Science.gov (United States)

    Byrd-Bredbenner, Carol; Quick, Virginia; Koenings, Mallory; Martin-Biggers, Jennifer; Kattelmann, Kendra K

    2016-04-01

    Little is known about the relationship between weight-related behaviors and cognitive load (working memory available to complete mental activities like those required for planning meals, selecting foods, and other health-related decisions). Thus, the purpose of this study was to explore associations between cognitive load and eating behaviors, physical activity, body mass index (BMI), and waist circumference of college students. College students (n=1018) from 13 institutions completed an online survey assessing eating behaviors (e.g., routine and compensatory restraint, emotional eating, and fruit/vegetable intake), stress level, and physical activity level. BMI and waist circumference were measured by trained researchers. A cognitive load score was derived from stress level, time pressure/income needs, race and nationality. High cognitive load participants (n=425) were significantly (Pcognitive loads (n=593). Compared to low cognitive load participants, high cognitive load participants were significantly more likely to eat cognitive load scores had a non-significant trend toward higher BMIs, waist circumferences, and drinking more alcohol than low cognitive load counterparts. In conclusion, cognitive load may be an important contributor to health behaviors. Understanding how cognitive load may affect eating and other weight-related behaviors could potentially lead to improvements in the effectiveness of obesity prevention and intervention programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. The relationship between motor competence and health-related fitness in children and adolescents.

    Science.gov (United States)

    Luz, Carlos; Rodrigues, Luís P; Meester, An De; Cordovil, Rita

    2017-01-01

    In the last twenty years, there has been increasing evidence that Motor Competence (MC) is vital for developing an active and healthy lifestyle. This study analyses the associations between motor competence and its components, with health-related fitness (HRF). A random sample of 546 children (278 males, mean = 10.77 years) divided into four age groups (7-8; 9-10; 11-12; 13-14 years old) was evaluated. A quantitative MC instrument (evaluating stability, locomotor and manipulative skills), a maximal multistage 20-m shuttle-run test and the handgrip test, height and BMI were used in the analyses. Pearson correlations and standard regression modelling were performed to explore the associations between variables. Moderate to strong significant correlations (0.49 < r < 0.73) were found between MC and HRF, for both sexes, and correlation values were stable across the age groups. The MC model explained 74% of the HRF variance, with the locomotor component being the highest predictor for the entire sample (β = .302; p < .001). Gender-related differences were found when boys and girls were analysed at each age group. Locomotor MC for girls was the most consistent significant predictor of HRF across all age groups (0.47 < β < 0.65; all p≤.001). For boys, significant predictors were locomotor and manipulative MC (0.21 < β < 0.49; all p < .05) in the two younger age groups (7-8 and 9-10 years) and stability (0.50 < β < 0.54; all p≤.001) for the older two age groups (11-12 and 13-14 years). These results support the idea that: (1) the relationship between overall MC and HRF is strong and stable across childhood and early adolescence; (2) when accounting for the different MC components, boys and girls show different relationship patterns with HFR across age.

  4. The relationship between motor competence and health-related fitness in children and adolescents.

    Directory of Open Access Journals (Sweden)

    Carlos Luz

    Full Text Available In the last twenty years, there has been increasing evidence that Motor Competence (MC is vital for developing an active and healthy lifestyle. This study analyses the associations between motor competence and its components, with health-related fitness (HRF.A random sample of 546 children (278 males, mean = 10.77 years divided into four age groups (7-8; 9-10; 11-12; 13-14 years old was evaluated. A quantitative MC instrument (evaluating stability, locomotor and manipulative skills, a maximal multistage 20-m shuttle-run test and the handgrip test, height and BMI were used in the analyses. Pearson correlations and standard regression modelling were performed to explore the associations between variables.Moderate to strong significant correlations (0.49 < r < 0.73 were found between MC and HRF, for both sexes, and correlation values were stable across the age groups. The MC model explained 74% of the HRF variance, with the locomotor component being the highest predictor for the entire sample (β = .302; p < .001. Gender-related differences were found when boys and girls were analysed at each age group. Locomotor MC for girls was the most consistent significant predictor of HRF across all age groups (0.47 < β < 0.65; all p≤.001. For boys, significant predictors were locomotor and manipulative MC (0.21 < β < 0.49; all p < .05 in the two younger age groups (7-8 and 9-10 years and stability (0.50 < β < 0.54; all p≤.001 for the older two age groups (11-12 and 13-14 years.These results support the idea that: (1 the relationship between overall MC and HRF is strong and stable across childhood and early adolescence; (2 when accounting for the different MC components, boys and girls show different relationship patterns with HFR across age.

  5. Catheter-related infections caused by Pseudomonas aeruginosa: virulence factors involved and their relationships.

    Science.gov (United States)

    Olejnickova, Katerina; Hola, Veronika; Ruzicka, Filip

    2014-11-01

    The nosocomial pathogen Pseudomonas aeruginosa is equipped with a large arsenal of cell-associated and secreted virulence factors which enhance its invasive potential. The complex relationships among virulence determinants have hitherto not been fully elucidated. In the present study, 175 catheter-related isolates were observed for the presence of selected virulence factors, namely extracellular enzymes and siderophore production, biofilm formation, resistance to antibiotics, and motility. A high percentage of the strains produced most of the tested virulence factors. A positive correlation was identified between the production of several exoproducts, and also between the formation of both types of biofilm. An opposite trend was observed between the two types of biofilm and the production of siderophores. Whereas the relationship between the submerged biofilm production (i.e. the biofilm formed on the solid surface below the water level) and the siderophore secretion was negative, the production of air-liquid interface (A-L) biofilm (i.e. the biofilm floating on the surface of the cultivation medium) and the siderophore secretion were positively correlated. All correlations were statistically significant at the level P = 0.05 with the correlation coefficient γ ≥ 0.50. Our results suggest that: (1) the co-production of the lytic enzymes and siderophores can play an important role in the pathogenesis of the catheter-related infections and should be taken into account when the virulence potential is assessed; (2) biofilm-positive strains are capable of forming both submerged and non-attached A-L biofilms; and (3) the different micro-environment in the submerged biofilm and A-L biofilm layers have opposite consequences for the production of other virulence factors. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  6. Relationship between Pesticide Metabolites, Cytokine Patterns, and Asthma-Related Outcomes in Rural Women Workers

    Directory of Open Access Journals (Sweden)

    Hussein H. Mwanga

    2016-09-01

    Full Text Available The objective of this study was to investigate the relationship between exposure to organophosphate (OP and pyrethroid (PYR pesticides with serum cytokine patterns and asthma-related outcomes among rural women workers. A cross-sectional study was conducted among rural women (n = 211, including those working and living on farms and nearby town dwellers. Pesticide exposure was assessed using urinary metabolite concentrations of OP and PYR pesticides. Health outcome assessment was ascertained through the European Community Respiratory Health Survey (ECRHS questionnaire, fractional exhaled nitric oxide (FeNO, and serum cytokines associated with asthma. The prevalence of doctor-diagnosed asthma was 11%, adult-onset asthma 9%, and current asthma 6%. In this population, the proportion of T helper type 2 (Th2 cytokines (interleukin (IL-4, IL-5, and IL-13 detectable in subjects was between 18% and 40%, while the proportion of non-Th2 cytokines (IL-6, IL-8, IL-10, IL-17, and interferon gamma was between 35% and 71%. Most Th2 and non-Th2 cytokines were positively associated with either OP or PYR metabolites. Non-Th2 cytokines showed much stronger associations with OP metabolites (Dimethyl phosphate OR = 4.23; 95% CI: 1.54–11.65 than Th2 cytokines (Dimethyl phosphate OR = 1.69; 95% CI: 0.83–3.46. This study suggests that exposure to most OP and some PYR pesticides may be associated with asthma-related cytokines, with non-Th2 cytokines demonstrating consistently stronger relationships.

  7. Glucocorticoid Receptor Related Genes: Genotype And Brain Gene Expression Relationships To Suicide And Major Depressive Disorder

    Science.gov (United States)

    Pantazatos, Spiro P.; Huang, Yung-yu; Rosoklija, Gorazd B.; Dwork, Andrew J.; Burke, Ainsley; Arango, Victoria; Oquendo, Maria A.; Mann, J. John

    2016-01-01

    Introduction We tested the relationship between genotype, gene expression and suicidal behavior and MDD in live subjects and postmortem samples for three genes, associated with the hypothalamic-pituitary-adrenal axis, suicidal behavior and major depressive disorder (MDD); FK506 binding protein 5 (FKBP5), Spindle and kinetochore-associated protein 2 (SKA2) and Glucocorticoid Receptor (NR3C1). Materials and Methods Single-nucleotide polymorphisms (SNPs) and haplotypes were tested for association with suicidal behavior and MDD in a live (N=277) and a postmortem sample (N=209). RNA-seq was used to examine gene and isoform-level brain expression postmortem (Brodmann Area 9) (N=59). Expression quantitative trait loci (eQTL) relationships were examined using a public database (UK Brain Expression Consortium). Results We identified a haplotype within the FKBP5 gene, present in 47% of the live subjects, that was associated with increased risk of suicide attempt (OR=1.58, t=6.03, p=0.014). Six SNPs on this gene, three SNPs on SKA2 and one near NR3C1 showed before-adjustment association with attempted suicide, and two SNPs of SKA2 with suicide death, but none stayed significant after adjustment for multiple testing. Only the SKA2 SNPs were related to expression in the prefrontal cortex. One NR3C1 transcript had lower expression in suicide relative to non-suicide sudden death cases (b=-0.48, SE=0.12, t=-4.02, adjusted p=0.004). Conclusion We have identified an association of FKBP5 haplotype with risk of suicide attempt and found an association between suicide and altered NR3C1 gene expression in the prefrontal cortex. Our findings further implicate hypothalamic pituitary axis dysfunction in suicidal behavior. PMID:27030168

  8. Determination of Three-Phase Relative Permeabilities under Reservoir Conditions by Hot Water and Steamflood Experiments Détermination de perméabilités relatives tri-phasiques en conditions de réservoir, à partir d'expériences de balayages à l'eau chaude et à la vapeur

    Directory of Open Access Journals (Sweden)

    Quettier L.

    2006-11-01

    Full Text Available In order to help the physical and numerical interpretation of Emeraude's steam pilot, two-phase waterfloods at four temperatures (between 30 and 240°C and a steamflood were performed in the laboratory using the same porous medium (compacted silt and under reservoir conditions. Dynamic isothermal displacements were interpreted with a thermal simulator taking into account capillary end effects. The corresponding oil-water relative permeability curves were obtained by matching observed pressure drop and oil production. Results show that temperature influences the end-point saturations but not the shape of the curves. The steamflood experiment was carried out in an adiabatic core holder. Oil stripping and production of a large amount of CO2 caused by dissolution of carbonates were pointed out. The numerical interpretation of this experiment, by making use of the oil-water relative permeabilities, provided the three-phase oil relative permeability which is an essential datum for numerical interpretation of a steam drive pilot. Then a parameter study was used to quantify the influence of the different mechanisms involved in hot water and steam floods. Dans le but de faciliter l'interprétation physique et numérique du pilote vapeur d' Emeraude, des balayages eau-huile à quatre températures (entre 30 et 240°C et un balayage à la vapeur ont été réalisés au laboratoire. Toutes ces expériences ont été effectuées sur le même milieu poreux (silt compacté et en conditions de réservoir. Les déplacements bi-phasiques isothermes, en écoulement transitoire, ont été interprétés avec un modèle numérique thermique qui prend en compte les effets capillaires aux extrémités de l'échantillon. Les courbes de perméabilités relatives dynamiques eau-huile sont déterminées par calage, sur les courbes expérimentales, de la différence de pression et de la production d'huile simulées. Les résultats montrent que la température influe sur les

  9. Reward-related decision making in older adults: relationship to clinical presentation of depression.

    Science.gov (United States)

    McGovern, Amanda R; Alexopoulos, George S; Yuen, Genevieve S; Morimoto, Sarah Shizuko; Gunning-Dixon, Faith M

    2014-11-01

    Impairment in reward processes has been found in individuals with depression and in the aging population. The purpose of this study was twofold: (1) to use an affective neuroscience probe to identify abnormalities in reward-related decision making in late-life depression; and (2) to examine the relationship of reward-related decision making abnormalities in depressed, older adults to the clinical expression of apathy in depression. We hypothesized that relative to older, healthy subjects, depressed, older patients would exhibit impaired decision making and that apathetic, depressed patients would show greater impairment in decision making than non-apathetic, depressed patients. We used the Iowa Gambling Task to examine reward-related decision making in 60 non-demented, older patients with non-psychotic major depression and 36 older, psychiatrically healthy participants. Apathy was quantified using the Apathy Evaluation Scale. Of those with major depression, 18 individuals reported clinically significant apathy, whereas 42 participants did not have apathy. Older adults with depression and healthy comparison participants did not differ in their performance on the Iowa Gambling Task. However, apathetic, depressed older adults adopted an advantageous strategy and selected cards from the conservative decks compared with non-apathetic, depressed older adults. Non-apathetic, depressed patients showed a failure to adopt a conservative strategy and persisted in making risky decisions throughout the task. This study indicates that apathy in older, depressed adults is associated with a conservative response style on a behavioral probe of the systems involved in reward-related decision making. This conservative response style may be the result of reduced sensitivity to rewards in apathetic individuals. Copyright © 2014 John Wiley & Sons, Ltd.

  10. Relationship between Health Literacy, Health-Related Behaviors and Health Status: A Survey of Elderly Chinese

    Directory of Open Access Journals (Sweden)

    Yong-Bing Liu

    2015-08-01

    Full Text Available Background: Despite the large volume of research dedicated to health-related behavior change, chronic disease costs continue to rise, thus creating a major public health burden. Health literacy, the ability to seek, understand, and utilize health information, has been identified as an important factor in the course of chronic conditions. Little research has been conducted on the relationship between health literacy and health-related behaviors and health status in elderly Chinese. The aim of this study was to elucidate the relationship between health literacy and health-related behaviors and health status in China. Methods: The subjects enrolled in this study were selected based on a stratified cluster random sampling design. Information involving >4500 older adults in 44 pension institutions in Urumqi, Changji, Karamay, and Shihezi of Xinjiang between September 2011 and June 2012 was collected. The Chinese Citizen Health Literacy Questionnaire (China Health Education Centre, 2008 and a Scale of the General Status were administered and the information was obtained through face-to-face inquiries by investigators. A total of 1452 respondents met the inclusion criteria. A total of 1452 questionnaires were issued and the valid response rate was 96.14% (1396 of 1452. Factors affecting health literacy and the relationship to health literacy were identified by one-way ANOVA and a multiple linear regression model. Results: The average health literacy level of the elderly in nursing homes was relatively low (71.74 ± 28.35 points. There were significant differences in the health literacy score among the factors of age, gender, race, education level, household income, marital conditions, and former occupation (p < 0.001. The health literacy score was significantly associated with smoking, drinking, physical exercise, and health examination (p < 0.001. The elderly with higher health literacy scores were significantly less likely to have risky behaviors

  11. Integrated petrophysical and reservoir characterization workflow to enhance permeability and water saturation prediction

    Science.gov (United States)

    Al-Amri, Meshal; Mahmoud, Mohamed; Elkatatny, Salaheldin; Al-Yousef, Hasan; Al-Ghamdi, Tariq

    2017-07-01

    Accurate estimation of permeability is essential in reservoir characterization and in determining fluid flow in porous media which greatly assists optimize the production of a field. Some of the permeability prediction techniques such as Porosity-Permeability transforms and recently artificial intelligence and neural networks are encouraging but still show moderate to good match to core data. This could be due to limitation to homogenous media while the knowledge about geology and heterogeneity is indirectly related or absent. The use of geological information from core description as in Lithofacies which includes digenetic information show a link to permeability when categorized into rock types exposed to similar depositional environment. The objective of this paper is to develop a robust combined workflow integrating geology and petrophysics and wireline logs in an extremely heterogeneous carbonate reservoir to accurately predict permeability. Permeability prediction is carried out using pattern recognition algorithm called multi-resolution graph-based clustering (MRGC). We will bench mark the prediction results with hard data from core and well test analysis. As a result, we showed how much better improvements are achieved in the permeability prediction when geology is integrated within the analysis. Finally, we use the predicted permeability as an input parameter in J-function and correct for uncertainties in saturation calculation produced by wireline logs using the classical Archie equation. Eventually, high level of confidence in hydrocarbon volumes estimation is reached when robust permeability and saturation height functions are estimated in presence of important geological details that are petrophysically meaningful.

  12. Low Permeability Polyimide Insulation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Resodyn Technologies proposes a new technology that enables the application of polyimide based cryogenic insulation with low hydrogen permeability. This effort...

  13. Modelling of water permeability in cementitious materials

    DEFF Research Database (Denmark)

    Guang, Ye; Lura, Pietro; van Breugel, K.

    2006-01-01

    This paper presents a network model to predict the permeability of cement paste from a numerical simulation of its microstructure. Based on a linked list pore network structure, the effective hydraulic conductivity is estimated and the fluid flow is calculated according to the Hagen-Poiseuille law....... The pressure gradient at all nodes is calculated with the Gauss elimination method and the absolute permeability of the pore network is calculated directly from Darcy's law. Finally, the permeability model is validated by comparison with direct water permeability measurements. According to this model...

  14. Exploring Coworker Relationships: Antecedents and Dimensions of Interpersonal Fit, Coworker Satisfaction, and Relational Models

    NARCIS (Netherlands)

    E.K. Byington (Eliza)

    2013-01-01

    textabstractManagement scholarship has revealed the myriad ways in which relationships between coworkers impact individual, team, and organizational phenomena. However, our scientific understanding of coworker relationships and what makes for satisfying connections with colleagues is still in its

  15. Migration of particulates in permeable rock columns

    International Nuclear Information System (INIS)

    Cropper, R.L.

    1982-01-01

    The migration of radioactive material through soil and permeable rock formations have become a major topic of concern due to the interest in the licensing of new radioactive waste disposal sites. Previously, research has been conducted in relation to deep repositories; however, similar situations arise in the vadose zone, where there is a higher probability of naturally-occurring particulates of organic nature and for the incursion of water. Test data has provided information which suggests that particulates will travel through porous media subject to various delay mechnisms and must be included in any consideration of waste migration. Data concerning particulate migration must and should be considered in the future when radioactive waste disposal sites are licensed

  16. Relationship between functional assessments and exercise-related changes during static balance.

    Science.gov (United States)

    Clifton, Daniel R; Harrison, Blain C; Hertel, Jay; Hart, Joseph M

    2013-04-01

    The Functional Movement Screen (FMS) is currently used for injury risk prediction, although researchers have not studied its relationships to injury risk factors. The purpose of this study was to compare FMS scores at rest to changes in static balance after exercise. Second, we examined FMS scores pre and post exercise. Twenty-five participants performed center of pressure (COP) measures and FMS testing. An acclimatization session for the FMS occurred on day 1, whereas day 2 involved COP measures for static balance and FMS testing before and after a 36-minute exercise protocol. Center of pressure standard deviations in the frontal (COPML-SD) and sagittal (COPAP-SD) planes, center of pressure velocity (COP-Velocity), center of pressure area (COP-Area), and FMS scores were recorded. No significant correlations occurred between preexercise FMS scores and change in COP measures. Preexercise hurdle step scores related to preexercise COPML-SD (p = -0.46), COPAP-SD (p = -0.43), and COP-Area (p = -0.50). Preexercise in-line lunge scores related to postexercise COPAP-SD (p = -0.44) and COP-Velocity (p = -0.39), whereas preexercise active straight leg raise (ASLR) scores related to postexercise COPML-SD (p = -0.46). Functional Movement Screen scores were not related to changes in static balance after exercise and may therefore not be useful to predict who will experience greater static balance deficits after exercise. Additionally, FMS scores did not differ before and after exercise. Clinicians aiming to identify injury risk from a general static balance standpoint may find the hurdle step, in-line lunge, and ASLR useful. Clinicians aiming to identify injury risk from a change in static balance standpoint may need to explore other screening tools.

  17. Relationships between craniocervical posture and pain-related disability in patients with cervico-craniofacial pain

    Science.gov (United States)

    López-de-Uralde-Villanueva, Ibai; Beltran-Alacreu, Hector; Paris-Alemany, Alba; Angulo-Díaz-Parreño, Santiago; La Touche, Roy

    2015-01-01

    Objectives This cross-sectional correlation study explored the relationships between craniocervical posture and pain-related disability in patients with chronic cervico-craniofacial pain (CCFP). Moreover, we investigated the test–retest intrarater reliability of two craniocervical posture measurements: head posture (HP) and the sternomental distance (SMD). Methods Fifty-three asymptomatic subjects and 60 CCFP patients were recruited. One rater measured HP and the SMD using a cervical range of motion device and a digital caliper, respectively. The Spanish versions of the neck disability index and the craniofacial pain and disability inventory were used to assess pain-related disability (neck disability and craniofacial disability, respectively). Results We found no statistically significant correlations between craniocervical posture and pain-related disability variables (HP and neck disability [r=0.105; P>0.05]; HP and craniofacial disability [r=0.132; P>0.05]; SMD and neck disability [r=0.126; P>0.05]; SMD and craniofacial disability [r=0.195; P>0.05]). A moderate positive correlation was observed between HP and SMD for both groups (asymptomatic subjects, r=0.447; CCFP patients, r=0.52). Neck disability was strongly positively correlated with craniofacial disability (r=0.79; Pposture, but these differences were very small (mean difference =1.44 cm for HP; 6.24 mm for SMD). The effect sizes reached by these values were estimated to be small for SMD (d=0.38) and medium for HP (d=0.76). Conclusion The results showed no statistically significant correlations between craniocervical posture and variables of pain-related disability, but a strong correlation between the two variables of disability was found. Our findings suggest that small differences between CCFP patients and asymptomatic subjects exist with respect to the two measurements used to assess craniocervical posture (HP and SMD), and these measures demonstrated high test–retest intrarater reliability for

  18. Decision trees to characterise the roles of permeability and solubility on the prediction of oral absorption

    OpenAIRE

    Newby, Danielle; Freitas, Alex. A.; Ghafourian, Taravat

    2015-01-01

    Oral absorption of compounds depends on many physiological, physiochemical and formulation factors. Two important properties that govern oral absorption are in vitro permeability and solubility, which are commonly used as indicators of human intestinal absorption. Despite this, the nature and exact characteristics of the relationship between these parameters are not well understood. In this study a large dataset of human intestinal absorption was collated along with in vitro permeability, aqu...

  19. Relationship between funding source and conclusion among nutrition-related scientific articles.

    Science.gov (United States)

    Lesser, Lenard I; Ebbeling, Cara B; Goozner, Merrill; Wypij, David; Ludwig, David S

    2007-01-01

    Industrial support of biomedical research may bias scientific conclusions, as demonstrated by recent analyses of pharmaceutical studies. However, this issue has not been systematically examined in the area of nutrition research. The purpose of this study is to characterize financial sponsorship of scientific articles addressing the health effects of three commonly consumed beverages, and to determine how sponsorship affects published conclusions. Medline searches of worldwide literature were used to identify three article types (interventional studies, observational studies, and scientific reviews) about soft drinks, juice, and milk published between 1 January, 1999 and 31 December, 2003. Financial sponsorship and article conclusions were classified by independent groups of coinvestigators. The relationship between sponsorship and conclusions was explored by exact tests and regression analyses, controlling for covariates. 206 articles were included in the study, of which 111 declared financial sponsorship. Of these, 22% had all industry funding, 47% had no industry funding, and 32% had mixed funding. Funding source was significantly related to conclusions when considering all article types (p = 0.037). For interventional studies, the proportion with unfavorable conclusions was 0% for all industry funding versus 37% for no industry funding (p = 0.009). The odds ratio of a favorable versus unfavorable conclusion was 7.61 (95% confidence interval 1.27 to 45.73), comparing articles with all industry funding to no industry funding. Industry funding of nutrition-related scientific articles may bias conclusions in favor of sponsors' products, with potentially significant implications for public health.

  20. Phylogenetic relationships among Lactuca (Asteraceae) species and related genera based on ITS-1 DNA sequences.

    Science.gov (United States)

    Koopman, W J; Guetta, E; van de Wiel, C C; Vosman, B; van den Berg, R G

    1998-11-01

    Internal transcribed spacer (ITS-1) sequences from 97 accessions representing 23 species of Lactuca and related genera were determined and used to evaluate species relationships of Lactuca sensu lato (s.l.). The ITS-1 phylogenies, calculated using PAUP and PHYLIP, correspond better to the classification of Feráková than to other classifications evaluated, although the inclusion of sect. Lactuca subsect. Cyanicae is not supported. Therefore, exclusion of subsect. Cyanicae from Lactuca sensu Feráková is proposed. The amended genus contains the entire gene pool (sensu Harlan and De Wet) of cultivated lettuce (Lactuca sativa). The position of the species in the amended classification corresponds to their position in the lettuce gene pool. In the ITS-1 phylogenies, a clade with L. sativa, L. serriola, L. dregeana, L. altaica, and L. aculeata represents the primary gene pool. L. virosa and L. saligna, branching off closest to this clade, encompass the secondary gene pool. L. virosa is possibly of hybrid origin. The primary and secondary gene pool species are classified in sect. Lactuca subsect. Lactuca. The species L. quercina, L. viminea, L. sibirica, and L. tatarica, branching off next, represent the tertiary gene pool. They are classified in Lactuca sect. Lactucopsis, sect. Phaenixopus, and sect. Mulgedium, respectively. L. perennis and L. tenerrima, classified in sect. Lactuca subsect. Cyanicae, form clades with species from related genera and are not part of the lettuce gene pool.

  1. Relationship between macular pigment and visual function in subjects with early age-related macular degeneration.

    Science.gov (United States)

    Akuffo, Kwadwo Owusu; Nolan, John M; Peto, Tunde; Stack, Jim; Leung, Irene; Corcoran, Laura; Beatty, Stephen

    2017-02-01

    To investigate the relationship between macular pigment (MP) and visual function in subjects with early age-related macular degeneration (AMD). 121 subjects with early AMD enrolled as part of the Central Retinal Enrichment Supplementation Trial (CREST; ISRCTN13894787) were assessed using a range of psychophysical measures of visual function, including best corrected visual acuity (BCVA), letter contrast sensitivity (CS), mesopic and photopic CS, mesopic and photopic glare disability (GD), photostress recovery time (PRT), reading performance and subjective visual function, using the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25). MP was measured using customised heterochromatic flicker photometry. Letter CS, mesopic and photopic CS, photopic GD and mean reading speed were each significantly (p0.05, for all). MP relates positively to many measures of visual function in unsupplemented subjects with early AMD. The CREST trial will investigate whether enrichment of MP influences visual function among those afflicted with this condition. ISRCTN13894787. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Relationship Between Healthy Life Style and Work-Related Factors Among Call Center Workers

    Directory of Open Access Journals (Sweden)

    Loreta Gustainienė

    2012-11-01

    Full Text Available Health-related issues are becoming very popular both in the broad spheres of the society and in organizations. Taking care of employee health helps the employer with maintaining and improving organizational effectiveness. The aim of the study was to identify and assess the relationship between the Five-Factor Wellness Model and work-related factors such as interpersonal conflicts, organizational constraints, workload, work-family conflict, decision latitude, transformational leadership, psychological job characteristics and perceived organizational support. The subjects of the study were 177 employees of a call center. Healthy lifestyle was measured applying a Five-Factor Wellness questionnaire (Myers, Sweeney 2005b. Physical symptoms, interpersonal conflicts, organizational constraints and workload were measured using respective scales designed by Spector and Jex (2007. Decision latitude was measured employing Karasek (1985 questionnaire. Work-family conflict was measured referring to a subscale of negative work-home interaction (Geurts et al. 2005. A transformational leadership style was measured using General Scale of transformational leadership (Carless et al. 2000. Perceived organizational support was measured using a short version of Perceived Organizational Support scale (Eisenberger et al. 1986. Research findings show that healthy lifestyle as measured by the Five-Factor Wellness Model was predicted by lower work-family conflict, whereas physical symptoms - by marked work-family conflict, decision latitude and gender (female.

  3. Relationship between Unwanted Pregnancy and Health-Related Quality of Life in Pregnant Women.

    Science.gov (United States)

    Ali, Azizi

    2016-06-01

    To determine the relationship between unwanted pregnancy and health-related quality of life in pregnant women. Case-control study. Department of Community Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran, from October 2013 to July 2014. Of the pregnant women who presented to primary healthcare centers of Kermanshah, Iran to receive prenatal care at 6 - 10 weeks of their pregnancy, those with unwanted pregnancy were selected as cases and those with wanted pregnancy were selected as control group. The selection process was done using multi-stage stratified random sampling. Frequency matching was applied to match the two groups. Quality of life was measured by the SF-36 questionnaire and was compared by the t-test. Relationship power between pregnancy type (wanted or unwanted pregnancy) and impairment of quality of life subscales as the outcome was assessed using odds ratio (OR). Frequency distribution of matched variables was not statistically different between the two studied groups. Mean scores of mental component summary and physical component summary as well as eight subscales (physical functioning, role, bodily pain, general health, vitality, social functioning, role emotional, and mental health) were lower in the unwanted pregnancy group compared to women with wanted pregnancy (p < 0.001). The highest high impairment odds ratio was highest for the mental component summary (MCS) (OR = 9.19; 95% CI = 5.17- 16.32) and vitality subscale (OR = 5.2; 95% CI = 2.89- 9.33). Mental health of the pregnant women with unwanted pregnancy is affected more than their physical health. Mental health in women with unwanted pregnancy is 9.19 times more likely to be reduced. Among mental health subscales, vitality (energy/fatigue) showed the highest decrease.

  4. Relationship Between Unwanted Pregnancy And Health-related Quality Of Life In Pregnant Women

    International Nuclear Information System (INIS)

    Ali, A.

    2016-01-01

    Objective: To determine the relationship between unwanted pregnancy and health-related quality of life in pregnant women. Study Design: Case-control study. Place and Duration of Study: Department of Community Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran, from October 2013 to July 2014. Methodology: Of the pregnant women who presented to primary healthcare centers of Kermanshah, Iran to receive prenatal care at 6 - 10 weeks of their pregnancy, those with unwanted pregnancy were selected as cases and those with wanted pregnancy were selected as control group. The selection process was done using multi-stage stratified random sampling. Frequency matching was applied to match the two groups. Quality of life was measured by the SF-36 questionnaire and was compared by the t-test. Relationship power between pregnancy type (wanted or unwanted pregnancy) and impairment of quality of life subscales as the outcome was assessed using odds ratio (OR). Result: Frequency distribution of matched variables was not statistically different between the two studied groups. Mean scores of mental component summary and physical component summary as well as eight subscales (physical functioning, role, bodily pain, general health, vitality, social functioning, role emotional, and mental health) were lower in the unwanted pregnancy group compared to women with wanted pregnancy (p < 0.001). The highest high impairment odds ratio was highest for the mental component summary (MCS) (OR = 9.19; 95 percentage CI = 5.17- 16.32) and vitality subscale (OR = 5.2; 95 percentage CI = 2.89- 9.33). Conclusion: Mental health of the pregnant women with unwanted pregnancy is affected more than their physical health. Mental health in women with unwanted pregnancy is 9.19 times more likely to be reduced. Among mental health subscales, vitality (energy/fatigue) showed the highest decrease. (author)

  5. Genetic disparity and relationship among quantitatively inherited yield related traits in diallel crosses of upland cotton

    International Nuclear Information System (INIS)

    Bibi, M.; Khan, N.U.; Mohammad, F.; Gul, R.; Idrees, M.; Sayal, O.U.; Khakwani, A.A.; Khan, I.A.

    2011-01-01

    In quantitative genetics, development of high yielding genotypes from parental cultivars of same ancestry is some what confusing as compared to genetically diverse parents. However, sufficient recombinations through allelic variations in mating of closely-related populations result in superior agronomic performance. Development of improved cotton genotypes is one of the prime objectives of any cotton breeding programmes. Genetic divergence and yield potential of parental cotton genotypes versus their diallel hybrids, relationship of yield with various morpho-yield traits and their heritability were studied in 8 X 8 F/sub 1/ diallel hybrids and their parental cultivars in Gossypium hirsutum L. during 2008-09 at Khyber Pakhtunkhwa Agricultural University, Peshawar, Pakistan. Highly significant (p less than or equal to 0.01) differences were observed among parental genotypes and F/sub 1/ populations for all the traits. Results revealed that F/sub 1/ hybrids i.e., CIM-506 X CIM-554, CIM-473 X CIM-554, CIM-446 X CIM-496 and CIM-446 X CIM-554 produced significantly higher number of sympodia, bolls per populations showed incredible performance for plant height, locules per boll and seeds plant and seed cotton yield. Some F/sub 1/ per locule. Seed cotton yield manifested positive association with morpho-yield traits which also accounted for greater genetic variations to yield being dependent trait. Heritabilities (broad sense) were moderate to high in magnitude for all populations with larger genetic potential, positive relationship between yield and yield traits. Results revealed that F1 contributing traits and moderate to high heritability can guide intensive selection and improvement per se in segregating populations. (author)

  6. Cancer-related Fatigue and its Relationship with Demographic and Clinical Characteristics

    Directory of Open Access Journals (Sweden)

    Maryam Chehrehgosha

    2013-10-01

    Full Text Available Background and objectives: Fatigue experience is a psychological experience therefore, the relevant caregivers’ acquaintance with this issueis the most important step in offering optimal care for the patients. Accordingly, this study was conductedto determine Cancer-related Fatigue and its Relationship with Demographic and Clinical Characteristics inCancer Patients.A cancer diagnosis is a highly undesirable event for anyone.Methods: characteristics form and the Multidimensional Fatigue Inventory. The data were analyzed with the SPSS-18 software and t-test and ANOVA and tukey post hoc test were used.In this analytical study, 150 cancer patients visiting the oncology unit, the Shafa Radiotherapy Center,and Gorgan’s 5th Azar Teaching Hospital in 2012, who were selected with a purposive sampling method,participated in the study for 4 months. The required information was collected using a demographic and clinicalResults: of treatment, 51.3% used chemotherapy-surgery-radiotherapy regimen, 24.7% surgery-chemotherapy regimen,14% used chemotherapy, 7.3% used radiotherapy, and 2.7% used surgery. The overall mean scoreof fatigue was 54.65±8.78 from 100. The variables of residence (P=0. 018, the duration of marriage(P=0.018, the treatment regimen type (P<0.001, and the family’s economic status (P<0.000 were found toThe patients’ mean age was 48.39±1.5 Of the patients, 55.3% had undergone less than 12 monthshave a significant relationship with fatigue.Conclusion: Psychological interventions, besides physical caring and nursing interventions play a significantrole in the all-inclusive management of cancer patients’ problems, in particular, their fatigue.

  7. Experimental study on the soil structure and permeability in aerated zone at CIRP's field test site

    International Nuclear Information System (INIS)

    Du Zhongde; Zhao Yingjie; Guo Zhiming

    2000-01-01

    Measurement of soil grain and pore size distribution, observation of soil microstructure and permeability test are used to study soil structure and permeability. The results show that soil heterogeneity in vertical soil profile is much great. The mean heterogeneity coefficient is 14.7. The eccentric rate of saturated permeability coefficient in vertical and horizontal direction is from 0.65 to 1.00. The mean coefficient is 0.93. So the soil can be considered to be isotropic from the view point of the groundwater dynamics. The permeability coefficient has more difference in different soil layers. In vertical profile, the saturated permeability coefficient is relatively great in upper and under layers. It is relatively small in middle layers

  8. The solubility-permeability interplay and its implications in formulation design and development for poorly soluble drugs.

    Science.gov (United States)

    Dahan, Arik; Miller, Jonathan M

    2012-06-01

    While each of the two key parameters of oral drug absorption, the solubility and the permeability, has been comprehensively studied separately, the relationship and interplay between the two have been largely ignored. For instance, when formulating a low-solubility drug using various solubilization techniques: what are we doing to the apparent permeability when we increase the solubility? Permeability is equal to the drug's diffusion coefficient through the membrane times the membrane/aqueous partition coefficient divided by the membrane thickness. The direct correlation between the intestinal permeability and the membrane/aqueous partitioning, which in turn is dependent on the drug's apparent solubility in the GI milieu, suggests that the solubility and the permeability are closely associated, exhibiting a certain interplay between them, and the current view of treating the one irrespectively of the other may not be sufficient. In this paper, we describe the research that has been done thus far, and present new data, to shed light on this solubility-permeability interplay. It has been shown that decreased apparent permeability accompanies the solubility increase when using different solubilization methods. Overall, the weight of the evidence indicates that the solubility-permeability interplay cannot be ignored when using solubility-enabling formulations; looking solely at the solubility enhancement that the formulation enables may be misleading with regards to predicting the resulting absorption, and hence, the solubility-permeability interplay must be taken into account to strike the optimal solubility-permeability balance, in order to maximize the overall absorption.

  9. Fracture network topology and characterization of structural permeability

    Science.gov (United States)

    Hansberry, Rowan; King, Rosalind; Holford, Simon

    2017-04-01

    other permeability indicators such as drilling fluid losses, and pore pressure measurements. Initial work with these techniques has led to new developments in our ability to image subsurface faults and fractures at a variety of scales from independent datasets. We establish a strong relationship between features identified using seismic attribute analysis and interpreted natural fractures. However, care must be taken to use these methods in a case-by-case basis, as controls on fracture distribution and orientation can vary significantly with both regional and local influences. These results outline and effective method by which structural permeability can be assessed with existing petroleum datasets. However, unlike the broad stress field, mapping fracture orientation and characteristics within the Australian Continent is complicated as the distribution, geometry, areal extent and connectivity of fracture networks can vary significantly.

  10. Relationship between diet-related indicators and overweight and obesity in older adults in rural Japan.

    Science.gov (United States)

    Ishikawa, M; Moriya, S; Yokoyama, T

    2017-01-01

    To identify the relationship between diet-related indicators and overweight and obesity in older adults in rural Japan. Cross-sectional survey. Obira, Hokkaido, Japan. Local residents aged between 65 and 74 years, except for those with poor health, were included. A health- and diet-related questionnaire was applied to participants house-to-house by trained health professionals. The following indicators were examined: number of meals, number of balanced meals, food diversity, food group diversity, chewing ability, alcohol intake habit, smoking habit, instrumental activities of daily living scores, age, and residing alone or with family. Of 550 residents, 317 residents completely responded to the questionnaire. Of these, 41 were had low body mass index (BMI≤20) and were excluded. This resulted in a sample of 307 subjects comprising 117 men and 190 women; 37.6% and 46.8% of men and women were classified as obese (BMI≥25), respectively. Women with a normal BMI (20diet-related indicators compared with women with high BMI. The mean number of meals per day of normal men was significantly higher than of obese men. Using logistic regression analysis (stepwise), it was found that the number of meals per day was associated with obesity in men (OR=3.02; 95% CI 0.91-9.98; P=0.071), and food diversity was significantly associated with obesity in women (OR=1.95; 95% CI 1.12-3.38; P=0.018). The associations between dietary indicators and obesity differed by sex. Food diversity may be a potential indicator to measure nutritional status in women.

  11. The green eyed monster in the bottle: Relationship contingent self-esteem, romantic jealousy, and alcohol-related problems.

    Science.gov (United States)

    DiBello, Angelo M; Rodriguez, Lindsey M; Hadden, Benjamin W; Neighbors, Clayton

    2015-10-01

    Previous research suggests that both jealousy and relationship contingent self-esteem (RCSE) are related to alcohol use and alcohol-related problems. No work, however, has examined these two constructs together as they relate to motives for alcohol use and alcohol-related problems. The current study aims to build upon emerging literature examining different types of jealousy (i.e., emotional, cognitive, and behavioral), relationship quality (i.e., satisfaction, commitment, closeness), RCSE, and alcohol use. More specifically, the current study aimed to examine the associations between RCSE and drinking to cope and RCSE and alcohol-related problems, in the context of the different types of jealousy. Moreover, the current study aimed to assess whether the associations between RCSE, jealousy, and drinking outcomes vary as a function of relationship quality. Two hundred and seventy seven individuals (87% female) at a large southern university participated in the study. They completed measures of RCSE, relationship satisfaction, commitment, closeness, and jealousy as well as alcohol-related outcomes. Using PROCESS, moderated mediational analyses were used to evaluate different types of jealousy as mediators of the association between RCSE and drinking to cope/alcohol-related problems. Further, we aimed to examine whether relationship quality moderated the association between RCSE and jealousy in predicting alcohol-related variables. Results indicated that cognitive jealousy mediated the association between both RCSE and drinking to cope and RCSE and alcohol-related problems. Further, relationship satisfaction, commitment, and closeness were all found to moderate the association between RSCE and cognitive jealousy such that at lower, but not higher levels of satisfaction, commitment, and closeness, cognitive jealousy mediated the association between RCSE and drinking to cope and RCSE and alcohol-related problems. Copyright © 2015. Published by Elsevier Ltd.

  12. Wetting phase permeability in a partially saturated horizontal fracture

    International Nuclear Information System (INIS)

    Nicholl, M.J.; Glass, R.J.

    1994-01-01

    Fractures within geologic media can dominate the hydraulic properties of the system. Therefore, conceptual models used to assess the potential for radio-nuclide migration in unsaturated fractured rock such as that composing Yucca Mountain, Nevada, must be consistent with flow processes in individual fractures. A major obstacle to the understanding and simulation of unsaturated fracture flow is the paucity of physical data on both fracture aperture structure and relative permeability. An experimental procedure is developed for collecting detailed data on aperture and phase structure from a transparent analog fracture. To facilitate understanding of basic processes and provide a basis for development of effective property models, the simplest possible rough-walled fracture is used. Stable phase structures of varying complexity are created within the horizontal analog fracture. Wetting phase permeability is measured under steady-state conditions. A process based model for wetting phase relative permeability is then explored. Contributions of the following processes to reduced wetting phase permeability under unsaturated conditions are considered: reduction in cross-sectional flow area, increased path length, localized flow restriction, and preferential occupation of large apertures by the non-wetting phase

  13. Factors Influencing Stormwater Mitigation in Permeable Pavement

    Directory of Open Access Journals (Sweden)

    Chun Yan Liu

    2017-12-01

    Full Text Available Permeable pavement (PP is used worldwide to mitigate surface runoff in urban areas. Various studies have examined the factors governing the hydrologic performance of PP. However, relatively little is known about the relative importance of these governing factors and the long-term hydrologic performance of PP. This study applied numerical models—calibrated and validated using existing experimental results—to simulate hundreds of event-based and two long-term rainfall scenarios for two designs of PP. Based on the event-based simulation results, rainfall intensity, rainfall volume, thickness of the storage layer and the hydraulic conductivity of the subgrade were identified as the most influential factors in PP runoff reduction. Over the long term, PP performed significantly better in a relatively drier climate (e.g., New York, reducing nearly 90% of runoff volume compared to 70% in a relatively wetter climate (e.g., Hong Kong. The two designs of PP examined performed differently, and the difference was more apparent in the relatively wetter climate. This study generated insights that will help the design and implementation of PP to mitigate stormwater worldwide.

  14. An improved method for permeability estimation of the bioclastic limestone reservoir based on NMR data.

    Science.gov (United States)

    Ge, Xinmin; Fan, Yiren; Liu, Jianyu; Zhang, Li; Han, Yujiao; Xing, Donghui

    2017-10-01

    Permeability is an important parameter in formation evaluation since it controls the fluid transportation of porous rocks. However, it is challengeable to compute the permeability of bioclastic limestone reservoirs by conventional methods linking petrophysical and geophysical data, due to the complex pore distributions. A new method is presented to estimate the permeability based on laboratory and downhole nuclear magnetic resonance (NMR) measurements. We divide the pore space into four intervals by the inflection points between the pore radius and the transversal relaxation time. Relationships between permeability and percentages of different pore intervals are investigated to investigate influential factors on the fluid transportation. Furthermore, an empirical model, which takes into account of the pore size distributions, is presented to compute the permeability. 212 core samples in our case show that the accuracy of permeability calculation is improved from 0.542 (SDR model), 0.507 (TIM model), 0.455 (conventional porosity-permeability regressions) to 0.803. To enhance the precision of downhole application of the new model, we developed a fluid correction algorithm to construct the water spectrum of in-situ NMR data, aiming to eliminate the influence of oil on the magnetization. The result reveals that permeability is positively correlated with percentages of mega-pores and macro-pores, but negatively correlated with the percentage of micro-pores. Poor correlation is observed between permeability and the percentage of meso-pores. NMR magnetizations and T 2 spectrums after the fluid correction agree well with laboratory results for samples saturated with water. Field application indicates that the improved method provides better performance than conventional models such as Schlumberger-Doll Research equation, Timur-Coates equation, and porosity-permeability regressions. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. An improved method for permeability estimation of the bioclastic limestone reservoir based on NMR data

    Science.gov (United States)

    Ge, Xinmin; Fan, Yiren; Liu, Jianyu; Zhang, Li; Han, Yujiao; Xing, Donghui

    2017-10-01

    Permeability is an important parameter in formation evaluation since it controls the fluid transportation of porous rocks. However, it is challengeable to compute the permeability of bioclastic limestone reservoirs by conventional methods linking petrophysical and geophysical data, due to the complex pore distributions. A new method is presented to estimate the permeability based on laboratory and downhole nuclear magnetic resonance (NMR) measurements. We divide the pore space into four intervals by the inflection points between the pore radius and the transversal relaxation time. Relationships between permeability and percentages of different pore intervals are investigated to investigate influential factors on the fluid transportation. Furthermore, an empirical model, which takes into account of the pore size distributions, is presented to compute the permeability. 212 core samples in our case show that the accuracy of permeability calculation is improved from 0.542 (SDR model), 0.507 (TIM model), 0.455 (conventional porosity-permeability regressions) to 0.803. To enhance the precision of downhole application of the new model, we developed a fluid correction algorithm to construct the water spectrum of in-situ NMR data, aiming to eliminate the influence of oil on the magnetization. The result reveals that permeability is positively correlated with percentages of mega-pores and macro-pores, but negatively correlated with the percentage of micro-pores. Poor correlation is observed between permeability and the percentage of meso-pores. NMR magnetizations and T2 spectrums after the fluid correction agree well with laboratory results for samples saturated with water. Field application indicates that the improved method provides better performance than conventional models such as Schlumberger-Doll Research equation, Timur-Coates equation, and porosity-permeability regressions.

  16. Crustal permeability: Introduction to the special issue

    Science.gov (United States)

    Ingebritsen, Steven E.; Gleeson, Tom

    2015-01-01

    The topic of crustal permeability is of broad interest in light of the controlling effect of permeability on diverse geologic processes and also timely in light of the practical challenges associated with emerging technologies such as hydraulic fracturing for oil and gas production (‘fracking’), enhanced geothermal systems, and geologic carbon sequestration. This special issue of Geofluids is also motivated by the historical dichotomy between the hydrogeologic concept of permeability as a static material property that exerts control on fluid flow and the perspective of economic geologists, geophysicists, and crustal petrologists who have long recognized permeability as a dynamic parameter that changes in response to tectonism, fluid production, and geochemical reactions. Issues associated with fracking, enhanced geothermal systems, and geologic carbon sequestration have already begun to promote a constructive dialog between the static and dynamic views of permeability, and here we have made a conscious effort to include both viewpoints. This special issue also focuses on the quantification of permeability, encompassing both direct measurement of permeability in the uppermost crust and inferential permeability estimates, mainly for the deeper crust.

  17. Effects of temperature, mechanical loading and of their interactions on the permeability of structural concrete

    International Nuclear Information System (INIS)

    Choinska, M.

    2006-11-01

    Concrete permeability may influence the durability of structures indirectly by controlling the penetration rate of aggressive agents, but also directly if the structure has a confinement role, like containment vessels of nuclear power plants for instance. In the industrial background on the safety of these structures, the objective of this study is to characterize the evolution of concrete permeability under the effects of temperature and mechanical loading. The permeability tests are performed on hollow concrete cylinders, subjected to temperature up to 150 C and compressive loading up to failure. Experimental results reveal that the effects of temperature and damage may be decoupled for the estimation of permeability and enable us to propose a relation between permeability, damage and temperature. However, this relation may only be applied in the pre-peak phase as concrete remains micro-cracked. In order to overcome this limit to be able to model also permeability increase in the post-peak phase, another parameter, which is crack opening, is introduced in the relation between permeability and damage. This problem, investigated by modelling, is exploited according to two approaches. The first one is based on the definition of a matching law between existing relations of permeability evolution with damage and with crack opening. With this approach the tendencies are similar to the observed ones on the experimental results. The second approach consists in linking from a mechanical point of view damage with crack opening in order to apply the Poiseuille's law for permeability determination. Experimental validation of this approach, emerging towards a continuous model capable to reproduce permeability variations of a concrete structure, constitutes a major perspective of this work. (author)

  18. Wave transmission over permeable submerged breakwaters; Transmision del oleaje en rompeolas sumergidos permeables

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-y-Zurvia-Flores, Jaime Roberto; Fragoso-Sandoval, Lucio [Instituto Politecnico Nacional(Mexico)

    2008-10-15

    The permeable submerged breakwaters represent a coastal protection alternative, where some degree of wave energy transmission is acceptable. Such would be the case of tourist beach protection in Mexico. In previous researches, like those performed by D'Angremond et al. (1996), Seabrook and Hall (1998), and Briganti et al. (2003), the empirical formulas developed, give only some limited information over the spatial distribution of wave energy over the structure. Therefore, a decision was made to conduct a study on a reduced physical model of a permeable submerged breakwater based on the results presented by those researchers and with possible applications. Therefore this paper presents the development of a study of wave transmission over permeable submerged breakwaters performed in a reduced physical model of different sections of a submerged rockfill breakwater of the trapezoidal type. This was done in a narrow wave flume with a hydraulic irregular wave generator controlled by a computer that was used to generate and to reproduce different types of irregular waves to be used in the tests. It also has a wave meter with four sensors, and they are connected to a computer in order to process the wave data. The main objective of the study was to determine in an experimental way the influence of the several parameters of submerged breakwater over the wave transmission coefficient. Our experimental results were comparable to those obtained by D'Angremond et al. (1996) and Seabrook and Hall (1998). The results show that the sumerged breakwater parameters of most influence over the wave transmission coefficient were relative submergence and the relative width crest of the sumerged breakwater, and that the formula by Seabrook and Hall correlates best with our results. [Spanish] Los rompeolas sumergidos permeables representan actualmente una alternativa de proteccion de costas, donde un cierto grado de transmision de energia del oleaje es aceptable, como seria el

  19. Colloid transport in dual-permeability media

    Science.gov (United States)

    Leij, Feike J.; Bradford, Scott A.

    2013-07-01

    It has been widely reported that colloids can travel faster and over longer distances in natural structured porous media than in uniform structureless media used in laboratory studies. The presence of preferential pathways for colloids in the subsurface environment is of concern because of the increased risks for disease caused by microorganisms and colloid-associated contaminants. This study presents a model for colloid transport in dual-permeability media that includes reversible and irreversible retention of colloids and first-order exchange between the aqueous phases of the two regions. The model may also be used to describe transport of other reactive solutes in dual-permeability media. Analytical solutions for colloid concentrations in aqueous and solid phases were obtained using Laplace transformation and matrix decomposition. The solutions proved convenient to assess the effect of model parameters on the colloid distribution. The analytical model was used to describe effluent concentrations for a bromide tracer and 3.2- or 1-μm-colloids that were observed after transport through a composite 10-cm long porous medium made up of a cylindrical lens or core of sand and a surrounding matrix with sand of a different grain size. The tracer data were described very well and realistic estimates were obtained for the pore-water velocity in the two flow domains. An accurate description was also achieved for most colloid breakthrough curves. Dispersivity and retention parameters were typically greater for the larger 3.2-μm-colloids while both reversible and irreversible retention rates tended to be higher for the finer sands than the coarser sand. The relatively small sample size and the complex flow pattern in the composite medium made it difficult to reach definitive conclusions regarding transport parameters for colloid transport.

  20. Effect of temperature on sandstone permeability

    DEFF Research Database (Denmark)

    Rosenbrand, Esther; Kjøller, Claus

    Hot water injection in geothermal sandstone aquifers is considered for seasonal energy storage in Denmark. However, an increase in the aquifer temperature might reduce permeability, and thereby increase production costs. An understanding of the factors that control permeability is required in order...... and the Klinkenberg procedure showed the expected correlation between the two measures, however, differences could be around one order of magnitude. In tight gas sandstones, permeability is often sensitive to net stress, which might change due to the pore pressure change in the Klinkenberg procedure. Besides...... affecting the Klinkenberg procedure, the combined effect of slip and changes in permeability would affect production during pressure depletion in tight gas sandstone reservoirs; therefore effects of gas slip and net stress on permeability were combined in a model based on the Klinkenberg equation. A lower...

  1. Microorganism Removal in Permeable Pavement Parking Lots ...

    Science.gov (United States)

    Three types of permeable pavements (pervious concrete, permeable interlocking concrete pavers, and porous asphalt) were monitored at the Edison Environmental Center in Edison, New Jersey for indicator organisms such as fecal coliform, enterococci, and E. coli. Results showed that porous asphalt had much lower concentration in monitored infiltrate compared to pervious concrete and permeable interlocking concrete pavers. Concentrations of monitored organisms in infiltrate from porous asphalt were consistently below the bathing water quality standard. Fecal coliform and enterococci exceeded bathing water quality standards more than 72% and 34% of the time for permeable interlocking concrete pavers and pervious concrete, respectively. Purpose is to evaluate the performance of permeable pavement in removing indicator organisms from infiltrating stormwater runoff.

  2. Permeability During Magma Expansion and Compaction

    Science.gov (United States)

    Gonnermann, Helge. M.; Giachetti, Thomas; Fliedner, Céline; Nguyen, Chinh T.; Houghton, Bruce F.; Crozier, Joshua A.; Carey, Rebecca J.

    2017-12-01

    Plinian lapilli from the 1060 Common Era Glass Mountain rhyolitic eruption of Medicine Lake Volcano, California, were collected and analyzed for vesicularity and permeability. A subset of the samples were deformed at a temperature of 975°, under shear and normal stress, and postdeformation porosities and permeabilities were measured. Almost all undeformed samples fall within a narrow range of vesicularity (0.7-0.9), encompassing permeabilities between approximately 10-15 m2 and 10-10 m2. A percolation threshold of approximately 0.7 is required to fit the data by a power law, whereas a percolation threshold of approximately 0.5 is estimated by fitting connected and total vesicularity using percolation modeling. The Glass Mountain samples completely overlap with a range of explosively erupted silicic samples, and it remains unclear whether the erupting magmas became permeable at porosities of approximately 0.7 or at lower values. Sample deformation resulted in compaction and vesicle connectivity either increased or decreased. At small strains permeability of some samples increased, but at higher strains permeability decreased. Samples remain permeable down to vesicularities of less than 0.2, consistent with a potential hysteresis in permeability-porosity between expansion (vesiculation) and compaction (outgassing). We attribute this to retention of vesicle interconnectivity, albeit at reduced vesicle size, as well as bubble coalescence during shear deformation. We provide an equation that approximates the change in permeability during compaction. Based on a comparison with data from effusively erupted silicic samples, we propose that this equation can be used to model the change in permeability during compaction of effusively erupting magmas.

  3. Dynamic relationships between motor skill competence and health-related fitness in youth.

    Science.gov (United States)

    Stodden, David F; Gao, Zan; Goodway, Jacqueline D; Langendorfer, Stephen J

    2014-08-01

    This cross-sectional study examined associations among motor skill competence (MSC) and health-related fitness (HRF) in youth. A convenient sample of 253 boys and 203 girls (aged 4-13 years) participated in the study. Associations among measures of MSC (throwing and kicking speed and standing long jump distance) and a composite measure of HRF (push-ups, curl-ups, grip strength and PACER test) across five age groups (4-5, 6-7, 8-9, 10-11 and 12-13 yrs.) were assessed using hierarchical regression modeling. When including all children, throwing and jumping were significantly associated with the composite HRF factor for both boys and girls (throw, t = 5.33; jump, t = 4.49) beyond the significant age effect (t = 4.98) with kicking approaching significance (t = 1.73, p = .08). Associations between throwing and kicking speed and HRF appeared to increase from early to middle to late childhood age ranges. Associations between jumping and HRF were variable across age groups. These results support the notion that the relationship between MSC and HRF performance are dynamic and may change across childhood. These data suggest that the development of object control skills in childhood may be important for the development and maintenance of HRF across childhood and into adolescence.

  4. Genotype-Phenotype Relationship in Patients and Relatives with SHOX Region Anomalies in the French Population.

    Science.gov (United States)

    Auger, Julie; Baptiste, Amandine; Benabbad, Imane; Thierry, Gaëlle; Costa, Jean-Marc; Amouyal, Mélanie; Kottler, Marie-Laure; Leheup, Bruno; Touraine, Renaud; Schmitt, Sébastien; Lebrun, Marine; Cormier Daire, Valérie; Bonnefont, Jean-Paul; de Roux, Nicolas; Elie, Caroline; Rosilio, Myriam

    2016-01-01

    The aim of our study was to describe a large population with anomalies involving the SHOX region, responsible for idiopathic short stature and Léri-Weill dyschondrosteosis (LWD), and to identify a possible genotype/phenotype correlation. We performed a retrospective multicenter study on French subjects with a SHOX region anomaly diagnosed by multiplex ligation-dependent probe amplification or Sanger sequencing. Phenotypes were collected in each of the 7 genetic laboratories practicing this technique for SHOX analysis. Among 205 index cases and 100 related cases, 91.3% had LWD. For index cases, median age at evaluation was 11.7 (9.0; 15.9) years and mean height standard deviation score was -2.3 ± 1.1. A deletion of either SHOX or PAR1 or both was found in 74% of patients. Duplications and point mutations/indels affected 8 and 18% of the population, respectively. Genotype-phenotype correlation showed that deletions were more frequently associated with Madelung deformity and mesomelic shortening in girls, as well as with presence of radiologic anomalies, than duplications. Our results highlight genotype-phenotype relationships in the French population with a SHOX defect and provide new information showing that clinical expression is milder in cases of duplication compared to deletions. © 2016 S. Karger AG, Basel.

  5. The Relationship Between Posttraumatic Growth and Psychosocial Variables in Survivors of State Terrorism and Their Relatives.

    Science.gov (United States)

    Cárdenas-Castro, Manuel; Faúndez-Abarca, Ximena; Arancibia-Martini, Héctor; Ceruti-Mahn, Cristián

    2017-08-01

    The present study explores reports of growth in survivors and family members of victims of state terrorism ( N = 254) in Chile from 1973 to 1990. The results indicate the presence of reports of posttraumatic growth ( M = 4.69) and a positive and statistically significant correlation with variables related to the life impact of the stressful events ( r = .46), social sharing of emotions ( r = .32), deliberate rumination ( r = .37), positive reappraisal ( r = .35), reconciliation ( r = .39), spiritual practices ( r = .33), and meaning in life ( r = .51). The relationship between growth and forgiveness is not statistically significant. The variables that best predict posttraumatic growth are positive reappraisal (β = .28), life impact (β = .24), meaning in life β = .23), and reconciliation (β = .20). The forward-method hierarchical model indicates that these variables are significant predictors of growth levels, R 2 = .53, F(8, 210) = 30.08, p state terrorism manage to grow after these experiences, and the redefinition of meaning in life and the positive reappraisal of the traumatic experiences are the elements that make it possible to create a new narrative about the past.

  6. Relationship between different approaches to derive weighting functions related to atmospheric remote sensing problems

    International Nuclear Information System (INIS)

    Rozanov, Vladimir V.; Rozanov, Alexei V.

    2007-01-01

    The paper is devoted to the investigation of the relationship between different methods used to derive weighting functions required to solve numerous inverse problems related to the remote sensing of the Earth's atmosphere by means of scattered solar light observations. The first method commonly referred to as the forward-adjoint approach is based on a joint solution of the forward and adjoint radiative transfer equations and the second one requires the linearized forward radiative transfer equation to be solved. In the framework of the forward-adjoint method we consider two approaches commonly used to derive the weighting functions. These approaches are referenced as the 'response function' and the 'formal solution' techniques, respectively. We demonstrate here that the weighting functions derived employing the formal solution technique can also be obtained substituting the analytical representations for the direct forward and direct adjoint intensities into corresponding expressions obtained in the framework of the response function technique. The advantages and disadvantages of different techniques are discussed

  7. Predicting Relationship of Smoking Behavior Among Male Saudi Arabian College Students Related to Their Religious Practice.

    Science.gov (United States)

    Almutairi, Khalid M

    2016-04-01

    This study describes the relationships of smoking behavior among a sample of male college students in Kingdom of Saudi Arabia (KSA) to their religious practice, parents' smoking behaviors and attitudes, peers' smoking behaviors and attitudes, and knowledge about the dangers of smoking. A 49-item questionnaire was developed and pilot tested in KSA. This questionnaire was completed during the academic year 2013 by 715 undergraduate male students at the King Saud University in Riyadh. 29.8% of the students were smokers (13.8% cigarette smokers, 7.3% sheesha smokers, and 27% cigarette and sheesha smokers). Students in the College of Education were much more likely to be smokers than the students in the College of Science. The differences between the College of Education and the College of Science was statistically significant (χ (2) = 16.864. df = 1, p = .001). Logistic regression analysis suggested that students who were more faithful in their practice of Islam were 15% less likely to smoke. Students who were more knowledgeable about the dangers of smoking were 8% less likely to smoke. The logistic analysis identified peers (friends) as the most powerful factor in predicting smoking. The four-factor model had an overall classification accuracy of 78%. The need to understand more fully the dynamics of peer relations among Saudi Arabian males as a basis for developing tobacco education/prevention programs. Prevention programs will need to include education and changes in the college level or earlier in KSA.

  8. Emergent Trust and Work Life Relationships: How to Approach the Relational Moment of Trust

    Directory of Open Access Journals (Sweden)

    Tone Bergljot Eikeland

    2015-10-01

    Full Text Available How do we trust? What does the basic mechanism of trust look like? These questions define the starting point for a comparison of the classic ideas of how trust works by Mayer et al. (1995, Möllering’s (2006 re-adaption of Giddens’, Simmel’s, and James’ classic ideas of trust, and a phenomenological approach focusing on “emergent trust.” Introducing the concept of emergent trust, the idea is to suggest a phenomenological approach to studies of trust in work-life relationships in professional organizations, as an alternative to trust as a cognitive attitude, where trust becomes a stable, individual possession. The term “emergent” demonstrates a trust that emerges in meetings between persons, it has an immediate, unconditional quality, and shows itself in situations of life where there is a potential for trust to appear. Trust’s basic relationality makes the person morally responsible for the other. Trust appears between persons, as an event, constituting risk and uncertainty as a natural and positive part of our lives. Still, in larger social settings, the responsibility of trust also disperses on to the work itself, and our wider social networks.

  9. The Influence of Corporate Governance Mechanism on the Relationship between Related Party Transactions and Earnings Management

    Directory of Open Access Journals (Sweden)

    Aria Farah Mita

    2014-04-01

    Full Text Available The objective of this study is to investigate the relationship between related party transactions (RPT and earnings management. This study argues there is a different influence between RPT a priori likely to result in expropriation and RPT a priori not likely to result in expropriation. RPT a priori likely to result in expropriation creates an incentive to management or controlling shareholder to overstate income to cover or mask their expropriation. This study uses non-absolute discretionary accruals based on Kazsnik model to proxy earnings management. Corporate governance mechanism should reduce the incentive to overstate income in a company that involves in RPT a priori likely to result in expropriation. The results of this study show that the earnings management (income increasing is affected by the existence of RPT a priori likely to result in expropriation and corporate governance mechanism, but it is not affected by the size/value of the transactions. As expected, companies involving in RPT a priori likely to result in expropriation with weak corporate governance mechanism, tend to manage earnings that increase income. We find that strong corporate governance mechanism decreases the discretionary accruals in companies which have RPT a priori likely to result in expropriation.

  10. The Dark Triad and three types of jealousy : Its’ relations among heterosexuals and homosexuals involved in a romantic relationship

    NARCIS (Netherlands)

    Barelds, Dick P.H.; Dijkstra, Pieternel; Groothof, Hinke A.K.; Pastoor, Charlotte D.

    2017-01-01

    The current study examined the relations between the three Dark Triad (DT) traits and three types of jealousy, among both heterosexual and homosexual men and women involved in a romantic relationship (n = 439). It was hypothesized that the three DT traits would be related positively to those types

  11. Out on the Web: The Relationship between Campus Climate and GLBT-Related Web-based Resources in Academic Libraries

    Science.gov (United States)

    Ciszek, Matthew P.

    2011-01-01

    This article explores the relationship between the perceived campus environment for gay, lesbian, bisexual, and transgender (GLBT) students at colleges and universities and how academic libraries have deployed GLBT-related resources on the Web. Recommendations are made for increasing GLBT-related materials and information in academic libraries.…

  12. Relationship between patients' oral health-related quality of life, satisfaction with dentition, and personality profiles.

    Science.gov (United States)

    Karasneh, Jumana; Al-Omiri, Mahmoud K; Al-Hamad, Khaled Q; Al Quran, Firas A M

    2009-11-01

    The aim of this study was to investigate the relationship between patients' oral health-related quality of life, satisfaction with their dentition, and their personality profiles. Eighty-four patients (30 males and 54 females; mean age 31.9+/-12.7 years) seeking routine dental treatment were recruited for this study. A "Dental Impact on Daily Living" (DIDL) questionnaire was used to assess dental satisfaction and impact on daily living. An "Oral Health Impact Profile" (OHIP) was used to measure self-reported discomfort, disability, and dysfunction caused by oral conditions. Oral health-related quality of life was assessed using the "United Kingdom Oral Health Related Quality of Life" measure (OHQoL-U.K). A "NEO Five Factor inventory" (NEO-FFI) was used to assess personality profiles. The dentition has a measurable impact on daily living as well as with satisfaction with appearance, pain levels, oral comfort, general performance, and eating capability (p=0.000). Younger patients had more profound oral health impacts (p=0.045) and higher neuroticism scores (0.043). OHIP scores were significantly related to OHQoL-UK scores (p=0.000). DIDL scores had significant correlations with OHIP and OHQoL-UK scores (p<0.05). Significant correlations were established between neuroticism and satisfaction with oral comfort, extraversion and total satisfaction and satisfaction with general performance, and openness and satisfaction with appearance (p<0.05). OHIP and OHQoL-UK scores had no significant correlations with psychological profiles. The status of the oral cavity can have a definitive impact on patients' daily living and quality of life regardless age, gender, and level of education. Patients' satisfaction with their dentition has definitive impacts on daily living, quality of life, and dental perceptions. Personality profiles (neuroticism; extraversion, and openness) may influence dental perceptions, play a significant role in shaping satisfaction with dentition, and help

  13. Relationships between genetic polymorphisms in inflammation-related factor gene and the pathogenesis of nasopharyngeal cancer.

    Science.gov (United States)

    Qu, Yan-Li; Yu, Hong; Chen, Yan-Zhi; Zhao, Yu-Xia; Chen, Guang-Jun; Bai, Lu; Liu, Dan; Su, Hong-Xin; Wang, He-Tong

    2014-09-01

    Our study aims to discuss the association between inflammation-related factors such as single nucleotide polymorphisms (SNPs) with susceptibility and recurrence in nasopharyngeal carcinoma. We used Taqman real-time polymerase chain reaction (PCR) to characterize the genetic variation of five SNPs in 194 nasopharyngeal carcinoma patients and 231 healthy subjects. All statistical analysis is performed with statistical product and service solutions v13.0; odds ratio (OR) value and 95 % confidence interval (CI) were calculated. There is no relationship between TGFβ1 -869 T/C, IL-6 -634C/G, TGFβ1 -509C/T, IL1 -511C/T and nasopharyngeal carcinoma susceptibility. Both single factor and multiple factors analysis showed that IL1a -889 T/T genotype is significantly associated with nasopharyngeal carcinoma in decreasing the risk of nasopharyngeal carcinoma. A highly significant association was found between IL1a -889 T/T genotype and protective genotype as defined by various pathological types. This is more obvious in the protective genotype of the non-keratin-type squamous carcinoma undifferentiated type. We also discovered that genotype G/G and C/G + G/G of IL6 -634 gene are associated with reduced recurrence of nasopharyngeal carcinoma. IL1a -889 gene polymorphism and susceptibility is related to nasopharyngeal carcinoma and can potentially decrease the risk of nasopharyngeal carcinoma in the Han Chinese population in north China. IL1-889 TT genotype is protective genotype for nasopharyngeal carcinoma. We have provided evidence that the GG genotype of the IL6 -634 gene is associated with recurrent risk of nasopharyngeal carcinoma. The G allele is the protective gene of nasopharyngeal carcinoma recurrence.

  14. The relationship between macroeconomic and industry-specific business cycle indicators and work-related injuris among Danish construction workers

    DEFF Research Database (Denmark)

    Nielsen, Kent Jacob; Lander, Flemming; Lauritsen, Jens

    2015-01-01

    Objectives The current study examines and compares the relationship between both macroeconomic and industry-specific business cycle indicators, and work-related injuries among construction workers in Denmark using emergency department (ED) injury data and also officially reported injuries...... (range 0.14–0.20) and WEA injuries (range 0.13–0.36). Furthermore, although there is some variability in the strength of the relationship of the different business cycle indicators, the relationships are generally not stronger for the WEA injuries than for the ED injuries, except for general unemployment....... Similarly, no substantial differences in strength of relation between industry-specific and macroeconomic indicators were identified. Conclusions The study shows that there was no difference in the relationship between business cycle indicators, and WEA and ED injury data. This indicates that changes...

  15. Relationships Among Tweets Related to Radiation: Visualization Using Co-Occurring Networks.

    Science.gov (United States)

    Yagahara, Ayako; Hanai, Keiri; Hasegawa, Shin; Ogasawara, Katsuhiko

    2018-03-15

    After the Fukushima Daiichi nuclear accident on March 11, 2011, interest in, and fear of, radiation increased among citizens. When such accidents occur, appropriate risk communication must provided by the government. It is therefore necessary to understand the fears of citizens in the days after such accidents. This study aimed to identify the progression of people's concerns, specifically fear, from a study of radiation-related tweets in the days after the Fukushima Daiichi nuclear accident. From approximately 1.5 million tweets in Japanese including any of the phrases "radiation" (), "radioactivity" (), and "radioactive substance" () sent March 11-17, 2011, we extracted tweets that expressed fear. We then performed a morphological analysis on the extracted tweets. Citizens' fears were visualized by creating co-occurrence networks using co-occurrence degrees showing relationship strength. Moreover, we calculated the Jaccard coefficient, which is one of the co-occurrence indices for expressing the strength of the relationship between morphemes when creating networks. From the visualization of the co-occurrence networks, we found high citizen interest in "nuclear power plant" on March 11 and 12, "health" on March 12 and 13, "medium" on March 13 and 14, and "economy" on March 15. On March 16 and 17, citizens' interest changed to "lack of goods in the afflicted area." In each co-occurrence network, trending topics, citizens' fears, and opinions to the government were extracted. This study used Twitter to understand changes in the concerns of Japanese citizens during the week after the Fukushima Daiichi nuclear accident, with a focus specifically on citizens' fears. We found that immediately after the accident, the interest in the accident itself was high, and then interest shifted to concerns affecting life, such as health and economy, as the week progressed. Clarifying citizens' fears and the dissemination of information through mass media and social media can add to

  16. An event-related potential investigation of the relationship between semantic and perceptual levels of representation

    NARCIS (Netherlands)

    Van Schie, H.T.; Wijers, A.A.; Kellenbach, M.L; Stowe, L.A.

    The present study was conducted to investigate relationships between semantic and perceptual levels of representation. A picture - word repetition paradigm was used in which we manipulated the semantic relationship between pictures and words. Experiment I involved two types of trials, one with words

  17. Relations between agreeableness and perceived support in family relationships: Why nice people are not always supportive

    NARCIS (Netherlands)

    Branje, S.J.T.; Lieshout, C.F.M. van; Aken, M.A.G. van

    2005-01-01

    Do more agreeable individuals perceive more support, and are they perceived as more supportive, across all family relationships or only within specific relationships? In a study of 256 Dutch two-parent families with two adolescents, we examine whether links between Agreeableness and support are

  18. Social Support Seeking in Relation to Parental Attachment and Peer Relationships among Victims of Cyberbullying

    Science.gov (United States)

    Ševcíková, Anna; Machácková, Hana; Wright, Michelle F.; Dedková, Lenka; Cerná, Alena

    2015-01-01

    Victims use social support seeking (SSS) to buffer the negative effects of cyberbullying. It is unknown whether cybervictims' perceptions of harm and having poor peer and parental relationships influence SSS. Using a sample of 451 cyberbullying-victims, aged 12-18, 68% girls, this study examined relationships of gender, harm, peer rejection,…

  19. Predicting skin permeability from complex chemical mixtures

    International Nuclear Information System (INIS)

    Riviere, Jim E.; Brooks, James D.

    2005-01-01

    Occupational and environmental exposure to topical chemicals is usually in the form of complex chemical mixtures, yet risk assessment is based on experimentally derived data from individual chemical exposures from a single, usually aqueous vehicle, or from computed physiochemical properties. We present an approach using hybrid quantitative structure permeation relationships (QSPeR) models where absorption through porcine skin flow-through diffusion cells is well predicted using a QSPeR model describing the individual penetrants, coupled with a mixture factor (MF) that accounts for physicochemical properties of the vehicle/mixture components. The baseline equation is log k p = c + mMF + aΣα 2 H + bΣβ 2 H + sπ 2 H + rR 2 + vV x where Σα 2 H is the hydrogen-bond donor acidity, Σβ 2 H is the hydrogen-bond acceptor basicity, π 2 H is the dipolarity/polarizability, R 2 represents the excess molar refractivity, and V x is the McGowan volume of the penetrants of interest; c, m, a, b, s, r, and v are strength coefficients coupling these descriptors to skin permeability (k p ) of 12 penetrants (atrazine, chlorpyrifos, ethylparathion, fenthion, methylparathion, nonylphenol, ρ-nitrophenol, pentachlorophenol, phenol, propazine, simazine, and triazine) in 24 mixtures. Mixtures consisted of full factorial combinations of vehicles (water, ethanol, propylene glycol) and additives (sodium lauryl sulfate, methyl nicotinate). An additional set of 4 penetrants (DEET, SDS, permethrin, ricinoleic acid) in different mixtures were included to assess applicability of this approach. This resulted in a dataset of 16 compounds administered in 344 treatment combinations. Across all exposures with no MF, R 2 for absorption was 0.62. With the MF, correlations increased up to 0.78. Parameters correlated to the MF include refractive index, polarizability and log (1/Henry's Law Constant) of the mixture components. These factors should not be considered final as the focus of these studies

  20. An asymptotic model of seismic reflection from a permeable layer

    Energy Technology Data Exchange (ETDEWEB)

    Silin, D.; Goloshubin, G.

    2009-10-15

    Analysis of compression wave propagation in a poroelastic medium predicts a peak of reflection from a high-permeability layer in the low-frequency end of the spectrum. An explicit formula expresses the resonant frequency through the elastic moduli of the solid skeleton, the permeability of the reservoir rock, the fluid viscosity and compressibility, and the reservoir thickness. This result is obtained through a low-frequency asymptotic analysis of Biot's model of poroelasticity. A review of the derivation of the main equations from the Hooke's law, momentum and mass balance equations, and Darcy's law suggests an alternative new physical interpretation of some coefficients of the classical poroelasticity. The velocity of wave propagation, the attenuation factor, and the wave number, are expressed in the form of power series with respect to a small dimensionless parameter. The absolute value of this parameter is equal to the product of the kinematic reservoir fluid mobility and the wave frequency. Retaining only the leading terms of the series leads to explicit and relatively simple expressions for the reflection and transmission coefficients for a planar wave crossing an interface between two permeable media, as well as wave reflection from a thin highly-permeable layer (a lens). Practical applications of the obtained asymptotic formulae are seismic modeling, inversion, and at-tribute analysis.

  1. Trench infiltration for managed aquifer recharge to permeable bedrock

    Science.gov (United States)

    Heilweil, V.M.; Watt, D.E.

    2011-01-01

    Managed aquifer recharge to permeable bedrock is increasingly being utilized to enhance resources and maintain sustainable groundwater development practices. One such target is the Navajo Sandstone, an extensive regional aquifer located throughout the Colorado Plateau of the western United States. Spreading-basin and bank-filtration projects along the sandstone outcrop's western edge in southwestern Utah have recently been implemented to meet growth-related water demands. This paper reports on a new cost-effective surface-infiltration technique utilizing trenches for enhancing managed aquifer recharge to permeable bedrock. A 48-day infiltration trench experiment on outcropping Navajo Sandstone was conducted to evaluate this alternative surface-spreading artificial recharge method. Final infiltration rates through the bottom of the trench were about 0.5 m/day. These infiltration rates were an order of magnitude higher than rates from a previous surface-spreading experiment at the same site. The higher rates were likely caused by a combination of factors including the removal of lower permeability soil and surficial caliche deposits, access to open vertical sandstone fractures, a reduction in physical clogging associated with silt and biofilm layers, minimizing viscosity effects by maintaining isothermal conditions, minimizing chemical clogging caused by carbonate mineral precipitation associated with algal photosynthesis, and diminished gas clogging associated with trapped air and biogenic gases. This pilot study illustrates the viability of trench infiltration for enhancing surface spreading of managed aquifer recharge to permeable bedrock. ?? 2010.

  2. Experimental study of very low permeability rocks using a high accuracy permeameter

    International Nuclear Information System (INIS)

    Larive, Elodie

    2002-01-01

    The measurement of fluid flow through 'tight' rocks is important to provide a better understanding of physical processes involved in several industrial and natural problems. These include deep nuclear waste repositories, management of aquifers, gas, petroleum or geothermal reservoirs, or earthquakes prevention. The major part of this work consisted of the design, construction and use of an elaborate experimental apparatus allowing laboratory permeability measurements (fluid flow) of very low permeability rocks, on samples at a centimetric scale, to constrain their hydraulic behaviour at realistic in-situ conditions. The accuracy permeameter allows the use of several measurement methods, the steady-state flow method, the transient pulse method, and the sinusoidal pore pressure oscillation method. Measurements were made with the pore pressure oscillation method, using different waveform periods, at several pore and confining pressure conditions, on different materials. The permeability of one natural standard, Westerly granite, and an artificial one, a micro-porous cement, were measured, and results obtained agreed with previous measurements made on these materials showing the reliability of the permeameter. A study of a Yorkshire sandstone shows a relationship between rock microstructure, permeability anisotropy and thermal cracking. Microstructure, porosity and permeability concepts, and laboratory permeability measurements specifications are presented, the permeameter is described, and then permeability results obtained on the investigated materials are reported [fr

  3. Experimental study of very-low permeability rocks by the implementation of a precision permeameter

    International Nuclear Information System (INIS)

    Larive, E.

    2002-12-01

    The measurement of fluid flow through 'tight' rocks is important to provide a better understanding of physical processes involved in several industrial and natural problems. These include deep nuclear waste repositories, management of aquifers, gas, petroleum or geothermal reservoirs, or earthquakes prevention. The major part of this work consisted of the design, construction and use of an elaborate experimental apparatus allowing laboratory permeability measurements (fluid flow) of very low permeability rocks, on samples at a centimetric scale, to constrain their hydraulic behaviour at realistic in-situ conditions.The accuracy permeameter allows the use of several measurement methods, the steady-state flow method, the transient pulse method and the sinusoidal pore pressure oscillation method. Measurements were made with the pore pressure oscillation method, using different waveform periods, at several pore and confining pressure conditions on different materials. The permeability of one natural standard, Westerly granite, and an artificial one, a micro-porous cement, were measured and results obtained agreed with previous measurements made on these materials showing the reliability of the permeameter. A study of a Yorkshire sandstone shows a relationship between rock microstructure, permeability anisotropy and thermal cracking. Microstructure, porosity and permeability concepts, and laboratory permeability measurements specifications are presented, the permeameter is described, and then permeability results obtained on the investigated materials are reported. (author)

  4. Relationship Quality and Alcohol-Related Social Reinforcement during Couples Interaction.

    Science.gov (United States)

    Fairbairn, Catharine E; Testa, Maria

    2016-01-01

    Individuals who are unhappy in their intimate partnerships are at risk for developing alcohol problems. But little is known about the mechanisms underlying this link. One possibility is that couples with poor relationship quality gain more reinforcement from alcohol in certain contexts-a possibility that has never previously been empirically examined. In the current study, 304 individuals (152 couples) were assigned to receive alcohol (target BAC .08%) or a non-alcoholic beverage. They then engaged in a conflict-resolution interaction with their partners. Videotaped interactions were coded by trained observers. Results revealed a significant interaction between alcohol and relationship quality across multiple measures. Alcohol decreased negative behaviors, decreased negative reciprocity, and enhanced self-reported experience to a greater extent during interactions involving individuals reporting low relationship quality and had comparatively little effect among those reporting high relationship quality. Findings point to a potential mechanism underlying problem drinking among couples with poor relationship quality.

  5. Suppression sours sacrifice: emotional and relational costs of suppressing emotions in romantic relationships.

    Science.gov (United States)

    Impett, Emily A; Kogan, Aleksandr; English, Tammy; John, Oliver; Oveis, Christopher; Gordon, Amie M; Keltner, Dacher

    2012-06-01

    What happens when people suppress their emotions when they sacrifice for a romantic partner? This multimethod study investigates how suppressing emotions during sacrifice shapes affective and relationship outcomes. In Part 1, dating couples came into the laboratory to discuss important romantic relationship sacrifices. Suppressing emotions was associated with emotional costs for the partner discussing his or her sacrifice. In Part 2, couples participated in a 14-day daily experience study. Within-person increases in emotional suppression during daily sacrifice were associated with decreases in emotional well-being and relationship quality as reported by both members of romantic dyads. In Part 3, suppression predicted decreases in relationship satisfaction and increases in thoughts about breaking up with a romantic partner 3 months later. In the first two parts of the study, authenticity mediated the costly effects of suppression. Implications for research on close relationships and emotion regulation are discussed.

  6. Knockout of MIMP protein in lactobacillus plantarum lost its regulation of intestinal permeability on NCM460 epithelial cells through the zonulin pathway.

    Science.gov (United States)

    Liu, Zhihua; Kang, Liang; Li, Chao; Tong, Chao; Huang, Meijin; Zhang, Xingwei; Huang, Nanqi; Moyer, Mary Pat; Qin, Huanlong; Wang, Jianping

    2014-10-03

    Previous studies indicated that the micro integral membrane protein located within the media place of the integral membrane protein of Lactobacillus plantarum CGMCC 1258 had protective effects against the intestinal epithelial injury. In our study, we mean to establish micro integral membrane protein -knockout Lactobacillus plantarum (LPKM) to investigate the change of its protective effects and verify the role of micro integral membrane protein on protection of normal intestinal barrier function. Binding assay and intestinal permeability were performed to verify the protective effects of micro integral membrane protein on intestinal permeability in vitro and in vivo. Molecular mechanism was also determined as the zonulin pathway. Clinical data were also collected for further verification of relationship between zonulin level and postoperative septicemia. LPKM got decreased inhibition of EPEC adhesion to NCM460 cells. LPKM had lower ability to alleviate the decrease of intestinal permeability induced by enteropathogenic-e.coli, and prevent enteropathogenic-e.coli -induced increase of zonulin expression. Overexpression of zonulin lowered the intestinal permeability regulated by Lactobacillus plantarum. There was a positive correlation between zonulin level and postoperative septicemia. Therefore, micro integral membrane protein could be necessary for the protective effects of Lactobacillus plantarum on intestinal barrier. MIMP might be a positive factor for Lactobacillus plantarum to protect the intestinal epithelial cells from injury, which could be related to the zonulin pathway.

  7. An efficient permeability scaling-up technique applied to the discretized flow equations

    Energy Technology Data Exchange (ETDEWEB)

    Urgelli, D.; Ding, Yu [Institut Francais du Petrole, Rueil Malmaison (France)

    1997-08-01

    Grid-block permeability scaling-up for numerical reservoir simulations has been discussed for a long time in the literature. It is now recognized that a full permeability tensor is needed to get an accurate reservoir description at large scale. However, two major difficulties are encountered: (1) grid-block permeability cannot be properly defined because it depends on boundary conditions; (2) discretization of flow equations with a full permeability tensor is not straightforward and little work has been done on this subject. In this paper, we propose a new method, which allows us to get around both difficulties. As the two major problems are closely related, a global approach will preserve the accuracy. So, in the proposed method, the permeability up-scaling technique is integrated in the discretized numerical scheme for flow simulation. The permeability is scaled-up via the transmissibility term, in accordance with the fluid flow calculation in the numerical scheme. A finite-volume scheme is particularly studied, and the transmissibility scaling-up technique for this scheme is presented. Some numerical examples are tested for flow simulation. This new method is compared with some published numerical schemes for full permeability tensor discretization where the full permeability tensor is scaled-up through various techniques. Comparing the results with fine grid simulations shows that the new method is more accurate and more efficient.

  8. Comparison of Mass Transfer Models for Determination of the Intestinal Permeability

    Directory of Open Access Journals (Sweden)

    P Zakeri-Milani

    2008-09-01

    Full Text Available Background and the purpose of the study: In determination of the permeability of the intestinal wall by external perfusion techniques, several models have been proposed. In the present study three models were used for experimental results that differ in their convection and diffusion assumptions. Material and Methods: Permeability coefficients for 13 compounds (metoprolol, propranolol, naproxen, ketoprofen, furosemide, hydrochlorothiazide, cimetidine, ranitidine, atenolol, piroxicam, antipyrine, ibuprofen and carbamazepine with known human intestinal permeability values were determined in anaesthetized rats by different mass transfer models and plotted versus the observed human intestinal permeabilities. Results: The calculated dimensionless wall permeability values were in the range of 0.37 - 4.85, 0.38-6.54 and 0.41-16.59 for complete radial mixing, mixing tank and laminar flow models respectively. The results indicated that all of the models work relatively well for our data despite fundamentally different assumptions. The wall permeabilities were in the order laminar flow > mixing tank > complete radial mixing. Conclusion: Although laminar flow model provides the most direct measure of the intrinsic wall permeability, it has limitations for highly permeable drugs such as ibuprofen. The normal physiological hydrodynamics is more complex and more investigation is required to find out the real hydrodynamics.

  9. Dynamic permeability and quantitative susceptibility

    DEFF Research Database (Denmark)

    Mikati, Abdul Ghani; Tan, Huan; Shenkar, Robert

    2014-01-01

    Hyperpermeability and iron deposition are 2 central pathophysiological phenomena in human cerebral cavernous malformation (CCM) disease. Here, we used 2 novel MRI techniques to establish a relationship between these phenomena....

  10. Permeability Barrier Generation in the Martian Lithosphere

    Science.gov (United States)

    Schools, Joe; Montési, Laurent

    2015-11-01

    Permeability barriers develop when a magma produced in the interior of a planet rises into the cooler lithosphere and crystallizes more rapidly than the lithosphere can deform (Sparks and Parmentier, 1991). Crystallization products may then clog the porous network in which melt is propagating, reducing the permeability to almost zero, i.e., forming a permeability barrier. Subsequent melts cannot cross the barrier. Permeability barriers have been useful to explain variations in crustal thickness at mid-ocean ridges on Earth (Magde et al., 1997; Hebert and Montési, 2011; Montési et al., 2011). We explore here under what conditions permeability barriers may form on Mars.We use the MELTS thermodynamic calculator (Ghiorso and Sack, 1995; Ghiorso et al., 2002; Asimow et al., 2004) in conjunction with estimated Martian mantle compositions (Morgan and Anders, 1979; Wänke and Dreibus, 1994; Lodders and Fegley, 1997; Sanloup et al., 1999; Taylor 2013) to model the formation of permeability barriers in the lithosphere of Mars. In order to represent potential past and present conditions of Mars, we vary the lithospheric thickness, mantle potential temperature (heat flux), oxygen fugacity, and water content.Our results show that permeability layers can develop in the thermal boundary layer of the simulated Martian lithosphere if the mantle potential temperature is higher than ~1500°C. The various Martian mantle compositions yield barriers in the same locations, under matching variable conditions. There is no significant difference in barrier location over the range of accepted Martian oxygen fugacity values. Water content is the most significant influence on barrier development as it reduces the temperature of crystallization, allowing melt to rise further into the lithosphere. Our lower temperature and thicker lithosphere model runs, which are likely the most similar to modern Mars, show no permeability barrier generation. Losing the possibility of having a permeability

  11. Phylogenetic Relationships of Citrus and Its Relatives Based on matK Gene Sequences

    Science.gov (United States)

    Penjor, Tshering; Uehara, Miki; Ide, Manami; Matsumoto, Natsumi; Matsumoto, Ryoji

    2013-01-01

    The genus Citrus includes mandarin, orange, lemon, grapefruit and lime, which have high economic and nutritional value. The family Rutaceae can be divided into 7 subfamilies, including Aurantioideae. The genus Citrus belongs to the subfamily Aurantioideae. In this study, we sequenced the chloroplast matK genes of 135 accessions from 22 genera of Aurantioideae and analyzed them phylogenetically. Our study includes many accessions that have not been examined in other studies. The subfamily Aurantioideae has been classified into 2 tribes, Clauseneae and Citreae, and our current molecular analysis clearly discriminate Citreae from Clauseneae by using only 1 chloroplast DNA sequence. Our study confirms previous observations on the molecular phylogeny of Aurantioideae in many aspects. However, we have provided novel information on these genetic relationships. For example, inconsistent with the previous observation, and consistent with our preliminary study using the chloroplast rbcL genes, our analysis showed that Feroniella oblata is not nested in Citrus species and is closely related with Feronia limonia. Furthermore, we have shown that Murraya paniculata is similar to Merrillia caloxylon and is dissimilar to Murraya koenigii. We found that “true citrus fruit trees” could be divided into 2 subclusters. One subcluster included Citrus, Fortunella, and Poncirus, while the other cluster included Microcitrus and Eremocitrus. Compared to previous studies, our current study is the most extensive phylogenetic study of Citrus species since it includes 93 accessions. The results indicate that Citrus species can be classified into 3 clusters: a citron cluster, a pummelo cluster, and a mandarin cluster. Although most mandarin accessions belonged to the mandarin cluster, we found some exceptions. We also obtained the information on the genetic background of various species of acid citrus grown in Japan. Because the genus Citrus contains many important accessions, we have

  12. Phylogenetic relationships of citrus and its relatives based on matK gene sequences.

    Directory of Open Access Journals (Sweden)

    Tshering Penjor

    Full Text Available The genus Citrus includes mandarin, orange, lemon, grapefruit and lime, which have high economic and nutritional value. The family Rutaceae can be divided into 7 subfamilies, including Aurantioideae. The genus Citrus belongs to the subfamily Aurantioideae. In this study, we sequenced the chloroplast matK genes of 135 accessions from 22 genera of Aurantioideae and analyzed them phylogenetically. Our study includes many accessions that have not been examined in other studies. The subfamily Aurantioideae has been classified into 2 tribes, Clauseneae and Citreae, and our current molecular analysis clearly discriminate Citreae from Clauseneae by using only 1 chloroplast DNA sequence. Our study confirms previous observations on the molecular phylogeny of Aurantioideae in many aspects. However, we have provided novel information on these genetic relationships. For example, inconsistent with the previous observation, and consistent with our preliminary study using the chloroplast rbcL genes, our analysis showed that Feroniella oblata is not nested in Citrus species and is closely related with Feronia limonia. Furthermore, we have shown that Murraya paniculata is similar to Merrillia caloxylon and is dissimilar to Murraya koenigii. We found that "true citrus fruit trees" could be divided into 2 subclusters. One subcluster included Citrus, Fortunella, and Poncirus, while the other cluster included Microcitrus and Eremocitrus. Compared to previous studies, our current study is the most extensive phylogenetic study of Citrus species since it includes 93 accessions. The results indicate that Citrus species can be classified into 3 clusters: a citron cluster, a pummelo cluster, and a mandarin cluster. Although most mandarin accessions belonged to the mandarin cluster, we found some exceptions. We also obtained the information on the genetic background of various species of acid citrus grown in Japan. Because the genus Citrus contains many important accessions

  13. Phylogenetic relationships of citrus and its relatives based on matK gene sequences.

    Science.gov (United States)

    Penjor, Tshering; Yamamoto, Masashi; Uehara, Miki; Ide, Manami; Matsumoto, Natsumi; Matsumoto, Ryoji; Nagano, Yukio

    2013-01-01

    The genus Citrus includes mandarin, orange, lemon, grapefruit and lime, which have high economic and nutritional value. The family Rutaceae can be divided into 7 subfamilies, including Aurantioideae. The genus Citrus belongs to the subfamily Aurantioideae. In this study, we sequenced the chloroplast matK genes of 135 accessions from 22 genera of Aurantioideae and analyzed them phylogenetically. Our study includes many accessions that have not been examined in other studies. The subfamily Aurantioideae has been classified into 2 tribes, Clauseneae and Citreae, and our current molecular analysis clearly discriminate Citreae from Clauseneae by using only 1 chloroplast DNA sequence. Our study confirms previous observations on the molecular phylogeny of Aurantioideae in many aspects. However, we have provided novel information on these genetic relationships. For example, inconsistent with the previous observation, and consistent with our preliminary study using the chloroplast rbcL genes, our analysis showed that Feroniella oblata is not nested in Citrus species and is closely related with Feronia limonia. Furthermore, we have shown that Murraya paniculata is similar to Merrillia caloxylon and is dissimilar to Murraya koenigii. We found that "true citrus fruit trees" could be divided into 2 subclusters. One subcluster included Citrus, Fortunella, and Poncirus, while the other cluster included Microcitrus and Eremocitrus. Compared to previous studies, our current study is the most extensive phylogenetic study of Citrus species since it includes 93 accessions. The results indicate that Citrus species can be classified into 3 clusters: a citron cluster, a pummelo cluster, and a mandarin cluster. Although most mandarin accessions belonged to the mandarin cluster, we found some exceptions. We also obtained the information on the genetic background of various species of acid citrus grown in Japan. Because the genus Citrus contains many important accessions, we have

  14. Relative age effect and its relationship with morphological characteristics and performance in young soccer players

    Directory of Open Access Journals (Sweden)

    Augusto Pedretti

    2015-05-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n3p367   In soccer, the relative age effect (RAE was observed in both adult and young players. The RAE appears to be more pronounced in elite sports, probably by the need to select the best players to compete internationally. This study review: (1 the prevalence of RAE in soccer players, (a considering competitive level (b and specific position and (2 association between RAE (a and anthropometric characteristics, (b physical fitness components and technical skills. A total of 12 studies met all inclusion criteria for this review. One trial (meta-analysis was included after the eligibility process. Overall, 77675 young soccer players were analysed. In all studies, significance level of 0.05 was set for the type I error. There is a consensus about the presence of an RAE in men’s soccer, and the percentage of players born in the first quarter in the selection year for professionals is high, with peak values found for elite young athletes, and a large decrease is evident throughout the regional and school representation. The relationship between RAE and the specific position is controversial, according to few studies. It is likely that players born in the first quarter differ in a variety of anthropometric characteristics and physical fitness components compared with peers born in the last quarter. Researchers need to understand the mechanisms by which RAE increase and decrease in order, to reduce and eliminate this social inequality that influence the experiences of athletes, especially in periods of development. Organizational and practical intervention is required.

  15. Permeability Tests on Silkeborg Sand No. 0000

    DEFF Research Database (Denmark)

    Lund, Willy; Jakobsen, Kim Parsberg

    on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Silkeborg Sand No. 0000. The permeability is determined by use of a falling head apparatus. The apparatus, test procedures and the analysis method are described......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

  16. Relationships between central arterial stiffness, lean body mass, and absolute and relative strength in young and older men and women.

    Science.gov (United States)

    Fahs, Christopher A; Thiebaud, Robert S; Rossow, Lindy M; Loenneke, Jeremy P; Bemben, Debra A; Bemben, Michael G

    2017-08-16

    Relationships between muscular strength and arterial stiffness as well as between muscle mass and arterial stiffness have been observed suggesting a link between the neuromuscular system and vascular health. However, the relationship between central arterial stiffness and absolute and relative strength along with muscle mass has not been investigated in both sexes across a broad age range. The purpose of this study was to examine the relationship between central arterial stiffness and absolute and relative strength as well as between central arterial stiffness and lean body mass (LBM) in men and women across a broad age range. LBM, central arterial stiffness and strength were measured on 36 men and 35 women between the ages of 18 and 75 years. Strength was measured on five machine resistance exercises and summed as one measure of overall strength (absolute strength). Relative strength was calculated as total strength divided by LBM (relative strength). Central arterial stiffness was inversely related to both absolute (r = -0·230; P = 0·029) and relative strength (r = -0·484; P LBM (r = 0·097; P = 0·213). The relationship between central arterial stiffness and relative strength was attenuated but still present when controlling for either age, per cent body fat, LBM or mean arterial pressure. These results suggest that, across a wide age range, the expression of relative muscular strength has a stronger relationship with central arterial stiffness compared to either LBM or absolute strength. This suggests that muscle function more than muscle mass may be coupled with vascular health. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  17. Understanding the relationship of long working hours with health status and health-related behaviours.

    Science.gov (United States)

    Artazcoz, L; Cortès, I; Escribà-Agüir, V; Cascant, L; Villegas, R

    2009-07-01

    The objectives of this study are to identify family and job characteristics associated with long work hours, to analyse the relationship between long work hours and several health indicators, and to examine whether gender differences for both objectives exist. The sample was composed of all salaried workers aged 16-64 years (3950 men and 3153 women) interviewed in the 2006 Catalonian Health Survey. Weekly work hours were categorised as less than 30 h (part-time), 30-40 (reference category), 41-50 and 51-60 h. Multiple logistic regression models separated by sex were fitted. Factors associated with long working hours differed by gender. Among men, extended work hours were related with being married or cohabiting and with being separated or divorced. In men, working 51-60 h a week was consistently associated with poor mental health status (aOR 2.06, 95% CI 1.31 to 3.24), self-reported hypertension (aOR 1.60, 95% CI 1.12 to 2.29), job dissatisfaction (aOR 2.05, 95% CI 1.49 to 2.82), smoking (aOR 1.33, 95% CI 1.03 to 1.72), shortage of sleep (aOR 1.42, 95% CI 1.09 to 1.85) and no leisure-time physical activity (aOR 2.43, 95% CI 1.64 to 3.60). Moreover, a gradient from standard working hours to 51-60 h a week was found for these six outcomes. Among women it was only related to smoking and to shortage of sleep. The association of overtime with different health indicators among men could be explained by their role as the family breadwinner: in situations of family financial stress men work overtime in order to increase the income and/or accept poor working conditions for fear of job loss, one of them being long working hours.

  18. Gender Differences in the Relations among Patriarchal Beliefs, Parenting and Teen Relationship Violence in Mexican Adolescents

    Science.gov (United States)

    Espinoza, Guadalupe; Hokoda, Audrey; Ulloa, Emilio C.; Ulibarri, Monica D.; Castaneda, Donna

    2012-01-01

    Teen relationship violence is a global phenomenon associated with adverse outcomes. As in other countries, teen relationship violence is of concern in Mexico. However, few studies have examined the risk and protective factors of teen relationship violence among Mexican adolescents. The current study examined whether patriarchal beliefs and exposure to authoritarian parenting among Mexican adolescents are associated with perpetration and victimization of physical and verbal-emotional teen relationship violence. Two hundred and four students (15 – 18 years old) from Monterrey, Mexico completed questionnaires. Hierarchical regression analyses controlling for age revealed that among girls, authoritarian parenting was associated with physical and verbal-emotional victimization and verbal-emotional violence perpetration. Among boys, higher endorsement of patriarchal beliefs was associated with lower reports of physical perpetration and physical victimization. PMID:23277734

  19. Romantic relationship stages and social networking sites: uncertainty reduction strategies and perceived relational norms on facebook.

    Science.gov (United States)

    Fox, Jesse; Anderegg, Courtney

    2014-11-01

    Due to their pervasiveness and unique affordances, social media play a distinct role in the development of modern romantic relationships. This study examines how a social networking site is used for information seeking about a potential or current romantic partner. In a survey, Facebook users (N=517) were presented with Facebook behaviors categorized as passive (e.g., reading a partner's profile), active (e.g., "friending" a common third party), or interactive (e.g., commenting on the partner's wall) uncertainty reduction strategies. Participants reported how normative they perceived these behaviors to be during four possible stages of relationship development (before meeting face-to-face, after meeting face-to-face, casual dating, and exclusive dating). Results indicated that as relationships progress, perceived norms for these behaviors change. Sex differences were also observed, as women perceived passive and interactive strategies as more normative than men during certain relationship stages.

  20. Does the "Special Relationship" Have a Role to Play in Future EU-US Relations?

    National Research Council Canada - National Science Library

    Hunter, James H

    2006-01-01

    .... However, despite the Solana Paper's statement that this trans-Atlantic relationship is one of the core elements of the international system, with the numerous trade and foreign policy conflicts...

  1. Relations between mothers' daily work, home, and relationship stress with characteristics of mother-child conflict interactions.

    Science.gov (United States)

    Nelson, Jackie A; Boyer, Brittany P; Villarreal, Deyaun L; Smith, Olivia A

    2017-06-01

    This study examined whether daily variations in levels of mothers' work, home, and relationship stress were related to collaborative and oppositional qualities of mother-child conflict interactions across 1 week. Mothers reported on 1 specific conflict interaction with their 5- to 8-year-old child and their work, home, and relationship stress through online surveys each day for 7 consecutive days. Diary data from 142 mothers were analyzed in 6 multilevel models, each including within- and between-family levels of a stressor predicting collaborative or oppositional conflict qualities. Results suggested that families in the sample differed from each other, and also varied during the week, in collaborative and oppositional conflict qualities as well as stress in all 3 domains. Mothers reported a greater degree of oppositional conflict qualities on days characterized by higher perceptions of home chaos. Additionally, mothers who reported higher average levels of negativity in romantic relationships endorsed oppositional conflict qualities to a greater extent than mothers with lower relationship negativity. Two multilevel models including all 3 stressors in relation to collaborative and oppositional conflict revealed that for mothers managing multiple roles, average romantic relationship stress was the most important unique contributor to mother-child conflict qualities and daily relationship stress was particularly influential among mothers with sons compared to those with daughters. Results support the spillover hypothesis of stress within the family system and are discussed in terms of mothers' coping mechanisms and emotional engagement. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Permeable Barrier Materials for Strontium Immobilization: - UFA Determination of Hydraulic Conductivity. - Column Sorption Experiments

    National Research Council Canada - National Science Library

    Moody, T

    1996-01-01

    Selected materials were tested to emulate a permeable barrier and to examine the: (1) capture efficiency of these materials relating to the immobilization of strontium-90 and hexavalent chromium in Hanford groundwater...

  3. Exploring Coworker Relationships: Antecedents and Dimensions of Interpersonal Fit, Coworker Satisfaction, and Relational Models

    OpenAIRE

    Byington, Eliza

    2013-01-01

    textabstractManagement scholarship has revealed the myriad ways in which relationships between coworkers impact individual, team, and organizational phenomena. However, our scientific understanding of coworker relationships and what makes for satisfying connections with colleagues is still in its early days. This dissertation helps advance our understanding by proposing new drivers of coworker satisfaction, unpacking the nature of coworker satisfaction itself, and examining the sources and an...

  4. Relationships between craniocervical posture and pain-related disability in patients with cervico-craniofacial pain

    Directory of Open Access Journals (Sweden)

    López-de-Uralde-Villanueva I

    2015-07-01

    Full Text Available Ibai López-de-Uralde-Villanueva,1–4 Hector Beltran-Alacreu,1–3 Alba Paris-Alemany,1–4 Santiago Angulo-Díaz-Parreño,2,3,5 Roy La Touche1–4 1Department of Physiotherapy, Faculty of Health Science, 2Research Group on Movement and Behavioral Science and Study of Pain, The Center for Advanced Studies University La Salle, Universidad Autónoma de Madrid, Aravaca, Madrid, Spain; 3Institute of Neuroscience and Craniofacial Pain (INDCRAN, Madrid, Spain; 4Hospital La Paz Institute for Health Research, IdiPAZ, Madrid, Spain; 5Faculty of Medicine, Universidad San Pablo CEU, Madrid, Spain Objectives: This cross-sectional correlation study explored the relationships between craniocervical posture and pain-related disability in patients with chronic cervico-craniofacial pain (CCFP. Moreover, we investigated the test–retest intrarater reliability of two craniocervical posture measurements: head posture (HP and the sternomental distance (SMD. Methods: Fifty-three asymptomatic subjects and 60 CCFP patients were recruited. One rater measured HP and the SMD using a cervical range of motion device and a digital caliper, respectively. The Spanish versions of the neck disability index and the craniofacial pain and disability inventory were used to assess pain-related disability (neck disability and craniofacial disability, respectively. Results: We found no statistically significant correlations between craniocervical posture and pain-related disability variables (HP and neck disability [r=0.105; P>0.05]; HP and craniofacial disability [r=0.132; P>0.05]; SMD and neck disability [r=0.126; P>0.05]; SMD and craniofacial disability [r=0.195; P>0.05]. A moderate positive correlation was observed between HP and SMD for both groups (asymptomatic subjects, r=0.447; CCFP patients, r=0.52. Neck disability was strongly positively correlated with craniofacial disability (r=0.79; P>0.001. The test–retest intrarater reliability of the HP measurement was high for

  5. A new model of special relativity and the relationship between the time warps of general and special relativity

    Science.gov (United States)

    Stannard, Warren B.

    2018-05-01

    Einstein’s two theories of relativity were introduced over 100 years ago. High school science students are seldom exposed to these revolutionary ideas as they are often perceived to be too difficult conceptually and mathematically. This paper brings together the two theories of relativity in a way that is logical and consistent and enables the teaching of relativity as a single subject. This paper introduces new models and analogies which are suitable for the teaching of Einstein’s relativity at a high school level, exposing students to our best understanding of time, space, matter and energy.

  6. Specificity of the Relationships Between Dysphoria and Related Constructs in an Outpatient Sample.

    Science.gov (United States)

    Starcevic, Vladan; Berle, David; Viswasam, Kirupamani; Hannan, Anthony; Milicevic, Denise; Brakoulias, Vlasios; Dale, Erin

    2015-12-01

    Dysphoria has recently been conceptualized as a complex emotional state that consists of discontent and/or unhappiness and a predominantly externalizing mode of coping with these feelings. The Nepean Dysphoria Scale (NDS) was developed on the basis of this model of dysphoria and used in this clinical study to ascertain the specificity of the relationships between dysphoria and relevant domains of psychopathology. Ninety-six outpatients completed the NDS, Symptom Checklist 90-Revised (SCL-90R) and Depression, Anxiety, Stress Scales, 21-item version (DASS-21). The scores on the NDS subscales (Discontent, Surrender, Irritability and Interpersonal Resentment) and total NDS scores correlated significantly with scores on the DASS-21 scales and relevant SCL-90R subscales. Multiple regression analyses demonstrated the following: DASS-21 Depression and Stress each had unique relationships with NDS Discontent and Surrender; DASS-21 Anxiety had a unique relationship with NDS Discontent; SCL-90R Hostility and Paranoid Ideation and DASS-21 Stress each had unique relationships with NDS Irritability; and SCL-90R Paranoid Ideation and DASS-21 Stress, Depression and Anxiety each had unique relationships with NDS Interpersonal Resentment. These findings support the notion that dysphoria is a complex emotional state, with both non-specific and specific relationships with irritability, tension, depression, paranoid tendencies, anxiety, hostility and interpersonal sensitivity. Conceptual rigor when referring to dysphoria should be promoted in both clinical practice and further research.

  7. The moderating role of social networks in the relationship between alcohol consumption and treatment utilization for alcohol-related problems

    Science.gov (United States)

    Mowbray, Orion

    2014-01-01

    Many individuals wait until alcohol use becomes severe before treatment is sought. However, social networks, or the number of social groups an individual belongs to, may play a moderating role in this relationship. Logistic regression examined the interaction of alcohol consumption and social networks as a predictor of treatment utilization while adjusting for sociodemographic and clinical variables among 1,433 lifetime alcohol-dependent respondents from wave 2 of the National Epidemiologic Survey on Alcohol Related Conditions (NESARC). Results showed that social networks moderate the relationship between alcohol consumption and treatment utilization such that for individuals with few network ties, the relationship between alcohol consumption and treatment utilization was diminished, compared to the relationship between alcohol consumption and treatment utilization for individuals with many network ties. Findings offer insight into how social networks, at times, can influence individuals to pursue treatment, while at other times, influence individuals to stay out of treatment, or seek treatment substitutes. PMID:24462223

  8. Evaluation of the effect of macerals on coal permeability in Tazareh and Parvadeh mines

    Directory of Open Access Journals (Sweden)

    Farhang Sereshki

    2016-08-01

    Full Text Available In recent decades, the subject of gas emission in underground coal mines in many countries is an important subject. Many factors affect in gas emissions in coal seams. Geological and physical structures of coal are affecting on gas emissions'. Also, composition and mineralization of coal, affect in coal permeability for different gases. In this study, the relationship between maceral composition and coal permeability in Tazareh and Parvadeh mines has been studied. Accordingly, a laboratory studies to investigate the relationship between coal composition and coal permeability was done. In coal samples, with MFORR equipment the permeability test was done. With microscopic analysis, the maceral contents of coal such as Inertinite and Vitrinite have been measured. Accordingly, many coal samples of Parvadeh and Tazareh coal mines have the pyrite as the dominant mineral matter. Parvadeh coal samples has the average percentage of Vitrinite equal 81.34% and 10.52% Inertinite. Also, in the Tazareh coal samples in Eastern Alborz coal mines, the average percentage of Vitrinite is 69.31% and inertinite is 22.47%. The average percentage of Pyrite content in Parvadeh coal samples in Tabas coal mines is 2.38% and in the Tazareh coal samples in Eastern Alborz coal mines is 2.62%.  The permeability test results have been shown, which, with increase of Inertinite contents, the permeability of coal is increasing. Also, test results have been shown, there was a reduction in the coal permeability with increasing of mineral contents and carbonate contents of the coal. So, the coal permeability in Tabas coal samples is more than Eastern Alborz coal samples.

  9. A New Model of Special Relativity and the Relationship between the Time Warps of General and Special Relativity

    Science.gov (United States)

    Stannard, Warren B.

    2018-01-01

    Einstein's two theories of relativity were introduced over 100 years ago. High school science students are seldom exposed to these revolutionary ideas as they are often perceived to be too difficult conceptually and mathematically. This paper brings together the two theories of relativity in a way that is logical and consistent and enables the…

  10. Borehole stoneley waves and permeability: Laboratory results

    International Nuclear Information System (INIS)

    Winkler, K.W.; Plona, T.J.; Froelich, B.; Liu, H.L.

    1987-01-01

    Recent interest in full waveform sonic logging has created the need for full waveform laboratory experiments on model boreholes. Of particular interest is the investigation of Stoneley waves and their interaction with permeable formations. The authors describe experimental results that show how Stoneley wave slowness and attenuation are affected by formation permeability. Both slowness and attenuation (1/Q) are observed to increase with formation permeability. This increase is frequency dependent, being greatest at low frequencies. The presence of simulated mudcakes on the borehole wall reduces the permeability effect on Stoneley waves, but does not eliminate it. The mudcake effect is frequency dependent, being greatest at low frequencies. In our experiments on rocks, the laboratory data is in qualitative agreement with theoretical predictions. In a very well characterized synthetic porous material, theory and experiment are in good quantitative agreement

  11. Octopus microvasculature: permeability to ferritin and carbon.

    Science.gov (United States)

    Browning, J

    1979-01-01

    The permeability of Octopus microvasculature was investigated by intravascular injection of carbon and ferritin. Vessels were tight to carbon while ferritin penetrated the pericyte junction, and was found extravascularly 1-2 min after its introduction. Vesicles occurred rarely in pericytes; fenestrae were absent. The discontinuous endothelial layer did not consitute a permeability barrier. The basement membrane, although retarding the movement of ferritin, was permeable to it; carbon did not penetrate the basement membrane. Evidence indicated that ferritin, and thus similarly sized and smaller water soluble materials, traverse the pericyte junction as a result of bulk fluid flow. Comparisons are made with the convective (or junctional) and slower, diffusive (or vesicular) passage of materials known to occur across the endothelium of continuous capillaries in mammals. Previous macrophysiological determinations concerning the permeability of Octopus vessels are questioned in view of these findings. Possible reasons for some major structural differences in the microcirculatory systems of cephalopods and vertebrates are briefly discussed.

  12. Dentin Permeability of Carious Primary Teeth

    African Journals Online (AJOL)

    primary dental pulp make it difficult to determine which modality offers the best ... The most common pathology of the dentine is dental caries. ... to evaluate dentine permeability is to calculate its hydraulic conductance (Lp) using fluid filtration ...

  13. Permeability After Impact Testing of Composite Laminates

    Science.gov (United States)

    Nettles, Alan T.

    2003-01-01

    Since composite laminates are beginning to be identified for use in reusable launch vehicle propulsion systems, an understanding of their permeance is needed. A foreign object impact event can cause a localized area of permeability (leakage) in a polymer matrix composite and it is the aim of this study to assess a method of quantifying permeability-after-impact results. A simple test apparatus is presented and variables that could affect the measured values of permeability-after-impact were assessed. Once it was determined that valid numbers were being measured, a fiber/resin system was impacted at various impact levels and the resulting permeability measured, first with a leak check solution (qualitative) then using the new apparatus (quantitative). The results showed that as the impact level increased, so did the measured leakage. As the pressure to the specimen was increased, the leak rate was seen to increase in a non-linear fashion for almost all of the specimens tested.

  14. Surface sedimentation at permeable pavement systems

    DEFF Research Database (Denmark)

    Støvring, Jan; Dam, Torben; Jensen, Marina Bergen

    2018-01-01

    Newly installed permeable pavement (PP) systems provide high surface infiltration capacity, but the accumulation of sediments causes a decrease in capacity over time, eventually leading to surface clogging. With the aim of investigating local sedimentation processes and the importance of restorat......Newly installed permeable pavement (PP) systems provide high surface infiltration capacity, but the accumulation of sediments causes a decrease in capacity over time, eventually leading to surface clogging. With the aim of investigating local sedimentation processes and the importance...

  15. Permeability and stress-jump effects on magnetic drug targeting in a permeable microvessel using Darcy model

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, S., E-mail: sachinshaw@gmail.com [Department of Mathematics and Statistical Sciences, Botswana International University of Science and Technology, Private Bag 16, Palapye (Botswana); Sutradhar, A.; Murthy, PVSN [Department of Mathematics, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal (India)

    2017-05-01

    In the present paper, we investigated the influence of permeability of the carrier particle and stress jump condition on the porous spherical surface in magnetic drug targeting through a permeable microvessel. The nature of blood is defined by non-Newtonian Casson fluid in the core region of the microvessel and Newtonian fluid in the peripheral region which is located near the surface of the wall of the microvessel. The magnetic particles are considered as spherical and in nanosize, embedded in the carrier particle along with drug particles. A magnet is placed near the tumor position to generate a magnetic field. The relative motion of the carrier particle is the resultant of the fluidic force, magnetic force and Saffman drag force which are calculated for the spherical carrier particle. Trajectories of the carrier particle along the radial and axial direction are calculated. Effect of different parameters such as stress-jump constant, permeability of the carrier particle, pressure gradient, yield stress, Saffman force, volume fraction of the embedded magnetic nanoparticles, permeability of the microvessel wall, and the radius of the carrier particle on the trajectory of the carrier particle are discussed and displayed graphically. - Highlights: • In the present manuscript, we considered the porous carrier particle which provide a larger surface area contact with the fluid than the solid spherical carrier particle. It shows that the porous carrier particle are captured easily than the solid carrier particle. • Introduce Suffman force on the carrier particle which commences an additional resistance which acts opposite to the surface wall and helps the particles to go away from the tumor position. • Considered stress jump condition at the surface of the porous carrier particle which enhanced the tendency of the carrier particle to be capture near the tumor. • Used Darcy model to define the permeability of the wall of the microvessel.

  16. Corporate Social Capital and Public Relations : Capital Accumulation by Social Relationship and Rethinking the Definition of Public Relations

    OpenAIRE

    北見, 幸一

    2009-01-01

    This paper discusses Corporate Social Capital and Public Relations. This paper overviewed the Social Capital studies, especially early studies in sociology field, proposed the framework to evaluate Social Capital in a capital. Social Capital has the merit to reduce transaction costs, and should be clearly positioned as a component of capital of corporation. Using the concept of the Corporate Social Capital, to rethink the definition of Public Relations, this paper proposed the following defin...

  17. Defining clogging potential for permeable concrete.

    Science.gov (United States)

    Kia, Alalea; Wong, Hong S; Cheeseman, Christopher R

    2018-08-15

    Permeable concrete is used to reduce urban flooding as it allows water to flow through normally impermeable infrastructure. It is prone to clogging by particulate matter and predicting the long-term performance of permeable concrete is challenging as there is currently no reliable means of characterising clogging potential. This paper reports on the performance of a range of laboratory-prepared and commercial permeable concretes, close packed glass spheres and aggregate particles of varying size, exposed to different clogging methods to understand this phenomena. New methods were developed to study clogging and define clogging potential. The tests involved applying flowing water containing sand and/or clay in cycles, and measuring the change in permeability. Substantial permeability reductions were observed in all samples, particularly when exposed to sand and clay simultaneously. Three methods were used to define clogging potential based on measuring the initial permeability decay, half-life cycle and number of cycles to full clogging. We show for the first time strong linear correlations between these parameters for a wide range of samples, indicating their use for service-life prediction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Accurate control testing for clay liner permeability

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, R J

    1991-08-01

    Two series of centrifuge tests were carried out to evaluate the use of centrifuge modelling as a method of accurate control testing of clay liner permeability. The first series used a large 3 m radius geotechnical centrifuge and the second series a small 0.5 m radius machine built specifically for research on clay liners. Two permeability cells were fabricated in order to provide direct data comparisons between the two methods of permeability testing. In both cases, the centrifuge method proved to be effective and efficient, and was found to be free of both the technical difficulties and leakage risks normally associated with laboratory permeability testing of fine grained soils. Two materials were tested, a consolidated kaolin clay having an average permeability coefficient of 1.2{times}10{sup -9} m/s and a compacted illite clay having a permeability coefficient of 2.0{times}10{sup -11} m/s. Four additional tests were carried out to demonstrate that the 0.5 m radius centrifuge could be used for linear performance modelling to evaluate factors such as volumetric water content, compaction method and density, leachate compatibility and other construction effects on liner leakage. The main advantages of centrifuge testing of clay liners are rapid and accurate evaluation of hydraulic properties and realistic stress modelling for performance evaluations. 8 refs., 12 figs., 7 tabs.

  19. Cell permeability beyond the rule of 5.

    Science.gov (United States)

    Matsson, Pär; Doak, Bradley C; Over, Björn; Kihlberg, Jan

    2016-06-01

    Drug discovery for difficult targets that have large and flat binding sites is often better suited to compounds beyond the "rule of 5" (bRo5). However, such compounds carry higher pharmacokinetic risks, such as low solubility and permeability, and increased efflux and metabolism. Interestingly, recent drug approvals and studies suggest that cell permeable and orally bioavailable drugs can be discovered far into bRo5 space. Tactics such as reduction or shielding of polarity by N-methylation, bulky side chains and intramolecular hydrogen bonds may be used to increase cell permeability in this space, but often results in decreased solubility. Conformationally flexible compounds can, however, combine high permeability and solubility, properties that are keys for cell permeability and intestinal absorption. Recent developments in computational conformational analysis will aid design of such compounds and hence prediction of cell permeability. Transporter mediated efflux occurs for most investigated drugs in bRo5 space, however it is commonly overcome by high local intestinal concentrations on oral administration. In contrast, there is little data to support significant impact of transporter-mediated intestinal absorption in bRo5 space. Current knowledge of compound properties that govern transporter effects of bRo5 drugs is limited and requires further fundamental and comprehensive studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Modeling the Relationship between Transportation-Related Carbon Dioxide Emissions and Hybrid-Online Courses at a Large Urban University

    Science.gov (United States)

    Little, Matthew; Cordero, Eugene

    2014-01-01

    Purpose: This paper aims to investigate the relationship between hybrid classes (where a per cent of the class meetings are online) and transportation-related CO[subscript 2] emissions at a commuter campus similar to San José State University (SJSU). Design/methodology/approach: A computer model was developed to calculate the number of trips to…

  1. The relationship between employment quality and work-related well-being in the European labor force

    NARCIS (Netherlands)

    Van Aerden, K.; Moors, G.B.D.; Levecque, K.; Vanroelen, C.

    2015-01-01

    In this article, data from the 2005 European Working Conditions Survey are used to examine the relationship between contemporary employment arrangements and the work-related well-being of European employees. By means of a Latent Class Cluster Analysis, several features of the employment conditions

  2. Adolescents' Susceptibility to Peer Pressure: Relations to Parent-Adolescent Relationship and Adolescents' Emotional Autonomy from Parents

    Science.gov (United States)

    Chan, Siu Mui; Chan, Kwok-Wai

    2013-01-01

    Studies on factors affecting susceptibility to peer pressure are not plentiful although this susceptibility has been found to be associated with youth problems such as substance use and risky sexual behavior. The present study examined how adolescents' susceptibility to peer pressure is related to their relationships with mothers and emotional…

  3. The Relationship between Instructor Misbehaviors and Student Antisocial Behavioral Alteration Techniques: The Roles of Instructor Attractiveness, Humor, and Relational Closeness

    Science.gov (United States)

    Claus, Christopher J.; Booth-Butterfield, Melanie; Chory, Rebecca M.

    2012-01-01

    Using rhetorical/relational goal theory as a guiding frame, we examined relationships between instructor misbehaviors (i.e., indolence, incompetence, and offensiveness) and the likelihood of students communicating antisocial behavioral alteration techniques (BATs). More specifically, the study focused on whether students' perceptions of instructor…

  4. Psychosocial Adaptation to Visual Impairment and Its Relationship to Depressive Affect in Older Adults with Age-Related Macular Degeneration

    Science.gov (United States)

    Tolman, Jennifer; Hill, Robert D.; Kleinschmidt, Julia J.; Gregg, Charles H.

    2005-01-01

    Purpose: In this study we examined psychosocial adaptation to vision loss and its relationship to depressive symptomatology in legally blind older adults with age-related macular degeneration (ARMD). Design and Methods: The 144 study participants were outpatients of a large regional vision clinic that specializes in the diagnosis and treatment of…

  5. The Relationship between Spiritual Well-Being and Health-Related Quality of Life in College Students

    Science.gov (United States)

    Anye, Ernest Tamanji; Gallien, Tara L.; Bian, Hui; Moulton, Michael

    2013-01-01

    Objective: This study investigated the relationship between spiritual well-being (SWB) and various aspects of health-related quality of life (HRQL) of college students. Participants and Methods: Two hundred twenty-five participants were surveyed during October 2010 to assess SWB and HRQL using the Spiritual Well-Being Scale and questions from the…

  6. Reactive, anxious and possessive forms of jealousy and their relation to relationship quality among heterosexuals and homosexuals

    NARCIS (Netherlands)

    Barelds, Dick P. H.; Dijkstra, Pieternel

    2006-01-01

    The present study examined the relationship between relational quality and three different types of jealousy-reactive, anxious and possessive jealousy. The sample consisted of 76 gay men, 79 lesbians, 70 heterosexual women and 70 heterosexual men. Findings show that different types of jealousy

  7. The Relationship between Teacher-Related Factors and Students' Attitudes towards Secondary School Chemistry Subject in Bureti District, Kenya

    Science.gov (United States)

    Chepkorir, Salome; Cheptonui, Edna Marusoi; Chemutai, Agnes

    2014-01-01

    This paper examines the relationship between teacher-related factors and student's attitudes towards Chemistry subject in secondary schools in Kenya. The paper is based on a study conducted in Bureti District in Kericho County, Kenya. This paper highlights issues on the teaching methods used by chemistry teachers, the teachers' availability to…

  8. Couples' Support-Related Communication, Psychological Distress, and Relationship Satisfaction among Women with Early Stage Breast Cancer

    Science.gov (United States)

    Manne, Sharon; Sherman, Marne; Ross, Stephanie; Ostroff, Jamie; Heyman, Richard E.; Fox, Kevin

    2004-01-01

    This study examined associations between couple communication about cancer and psychological distress and relationship satisfaction of women diagnosed with early stage breast cancer. One hundred forty-eight couples completed a videotaped discussion of a cancer-related issue and a general issue. Patients completed measures of psychological distress…

  9. Can You Read My Mind? Age as a Moderator in the Relationship between Theory of Mind and Relational Aggression

    Science.gov (United States)

    Gomez-Garibello, Carlos; Talwar, Victoria

    2015-01-01

    The present study examined whether age moderates the relationship between cognitive factors (theory of mind and attribution of intentions) and relational aggression. Participants (N = 426; 216 boys) between 6 and 9 years of age were asked to complete theory of mind tasks and answer an attribution of intentions questionnaire. Teachers evaluated…

  10. Trajectories of Change and Relationship between Parent-Adolescent School-Related Conflict and Academic Achievement in Early Adolescence

    Science.gov (United States)

    Brkovic, Irma; Keresteš, Gordana; Puklek Levpušc?ek, Melita

    2014-01-01

    The study explored changes in parent-adolescent school-related conflict rate and academic performance over a 5-year period among Croatian early adolescents and gender differences in these changes. Furthermore, it examined the relationship between conflict and achievement. The study was performed by applying an accelerated approach to overlapping…

  11. Relational-Cultural Theory as a Framework for Mentoring in Academia: Toward Diversity and Growth-Fostering Collaborative Scholarly Relationships

    Science.gov (United States)

    Lewis, Consuella; Olshansky, Ellen

    2016-01-01

    Mentoring in academia that encourages collaboration and interpersonal relationships is important in helping newer faculty members attain success. Developing such programs is challenging within our prevailing academic context that rewards competition and individually delineated success. We propose that Relational Cultural Theory, a feminist…

  12. The Relational-Behavior Model: The Relationship between Intrinsic Motivational Instruction and Extrinsic Motivation in Psychologically Based Instruction

    Science.gov (United States)

    Chandler, Donald S., Jr.

    2008-01-01

    This pilot study examined the relational-behavior model (RBM) as a method of intrinsic motivational instruction in psychology courses. Among a sample of 33 college students enrolled in two undergraduate psychology courses, a Spearman rho analysis revealed a significant relationship between the intrinsic motivational factors (e.g. student/class…

  13. Exploring the Relationship between Experiential Avoidance, Alcohol Use Disorders, and Alcohol-Related Problems among First-Year College Students

    Science.gov (United States)

    Levin, Michael E.; Lillis, Jason; Seeley, John; Hayes, Steven C.; Pistorello, Jacqueline; Biglan, Anthony

    2012-01-01

    Objective: This study explored the relationship of experiential avoidance (eg, the tendency to avoid, suppress, or otherwise control internal experiences even when doing so causes behavioral harm) to alcohol use disorders and alcohol-related problems. Participants: Cross-sectional data were collected from 240 undergraduate college students in…

  14. The Broader Context of Relational Aggression in Adolescent Romantic Relationships: Predictions from Peer Pressure and Links to Psychosocial Functioning

    Science.gov (United States)

    Schad, Megan M.; Szwedo, David E.; Antonishak, Jill; Hare, Amanda; Allen, Joseph P.

    2008-01-01

    The broader context of relational aggression in adolescent romantic relationships was assessed by considering the ways such aggression emerged from prior experiences of peer pressure and was linked to concurrent difficulties in psychosocial functioning. Longitudinal, multi-reporter data were obtained from 97 adolescents and their best friends at…

  15. Examining Relational Engagement across the Transition to High Schools in Three US High Schools Reformed to Improve Relationship Quality

    Science.gov (United States)

    Davis, Heather A.; Chang, Mei-Lin; Andrzejewski, Carey E.; Poirier, Ryan R.

    2014-01-01

    The purpose of this study was to examine changes in students' relational engagement across the transition to high school in three schools reformed to improve the quality of student-teacher relationships. In order to analyze this data we employed latent growth curve (LGC) modeling techniques (n = 637). We ran three LGC models on three…

  16. Stress among Student Affairs Administrators: The Relationship of Personal Characteristics and Organizational Variables to Work-Related Stress.

    Science.gov (United States)

    Berwick, Kathleen R.

    1992-01-01

    Examined possible relationships between reported work-related stress and organizational and personal variables, hardiness of personality, exercise activity, and organizational culture of 240 student affairs administrators within Minnesota. Results revealed that job satisfaction and hardiness of personality were greatest predictors of lowered…

  17. Interpreting Measures of Fundamental Movement Skills and Their Relationship with Health-Related Physical Activity and Self-Concept

    Science.gov (United States)

    Jarvis, Stuart; Williams, Morgan; Rainer, Paul; Jones, Eleri Sian; Saunders, John; Mullen, Richard

    2018-01-01

    The aims of this study were to determine proficiency levels of fundamental movement skills using cluster analysis in a cohort of U.K. primary school children; and to further examine the relationships between fundamental movement skills proficiency and other key aspects of health-related physical activity behavior. Participants were 553 primary…

  18. The Relationship of Public Relations and Board-Level Boundary-Spanning Roles to Corporate Social Responsibility.

    Science.gov (United States)

    Ferguson, Mary Ann; And Others

    The annual reports of 197 publicly held American corporations were analyzed to determine the relationship of corporate social responsibility activities to boundary-spanning activities (attempts to relate the firm to the outside world). Data gathered included (1) the number of directors from inside and outside a corporation, (2) the number of…

  19. Trauma-Related Guilt Mediates the Relationship between Posttraumatic Stress Disorder and Suicidal Ideation in OEF/OIF/OND Veterans.

    Science.gov (United States)

    Tripp, Jessica C; McDevitt-Murphy, Meghan E

    2017-02-01

    Posttraumatic stress disorder (PTSD) and trauma-related guilt are risk factors for suicidal ideation (SI) in veterans. Components of trauma-related guilt were examined as serial mediators of the relationship between PTSD and SI. In a sample of 53 OEF/OIF/OND combat veterans, PTSD had an indirect effect on SI through a serial mediation chain of guilt cognitions, distress, and global guilt, suggesting that trauma-related guilt via cognitions, distress, and global guilt is a pathway from PTSD to SI. Attention should be given to assessing and addressing trauma-related guilt in veterans experiencing PTSD to prevent SI. © 2016 The American Association of Suicidology.

  20. Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods.

    Science.gov (United States)

    Li, Hui; Kayhanian, Masoud; Harvey, John T

    2013-03-30

    Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50-90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. EMD-regression for modelling multi-scale relationships, and application to weather-related cardiovascular mortality

    Science.gov (United States)

    Masselot, Pierre; Chebana, Fateh; Bélanger, Diane; St-Hilaire, André; Abdous, Belkacem; Gosselin, Pierre; Ouarda, Taha B. M. J.

    2018-01-01

    In a number of environmental studies, relationships between natural processes are often assessed through regression analyses, using time series data. Such data are often multi-scale and non-stationary, leading to a poor accuracy of the resulting regression models and therefore to results with moderate reliability. To deal with this issue, the present paper introduces the EMD-regression methodology consisting in applying the empirical mode decomposition (EMD) algorithm on data series and then using the resulting components in regression models. The proposed methodology presents a number of advantages. First, it accounts of the issues of non-stationarity associated to the data series. Second, this approach acts as a scan for the relationship between a response variable and the predictors at different time scales, providing new insights about this relationship. To illustrate the proposed methodology it is applied to study the relationship between weather and cardiovascular mortality in Montreal, Canada. The results shed new knowledge concerning the studied relationship. For instance, they show that the humidity can cause excess mortality at the monthly time scale, which is a scale not visible in classical models. A comparison is also conducted with state of the art methods which are the generalized additive models and distributed lag models, both widely used in weather-related health studies. The comparison shows that EMD-regression achieves better prediction performances and provides more details than classical models concerning the relationship.

  2. Gay and Bisexual Adolescent Boys' Perspectives on Parent-Adolescent Relationships and Parenting Practices Related to Teen Sex and Dating.

    Science.gov (United States)

    Feinstein, Brian A; Thomann, Matthew; Coventry, Ryan; Macapagal, Kathryn; Mustanski, Brian; Newcomb, Michael E

    2017-12-26

    Close parent-adolescent relationships and specific parenting practices (e.g., communication about sex, monitoring) are associated with reduced sexual risk behavior among heterosexual youth. Despite gay/bisexual male youth being at increased risk of HIV, little is known about parental influences on their sexual behavior. As such, the goal of the current study was to examine parent-adolescent relationships and parenting practices related to teen sex and dating from the perspective of gay/bisexual adolescent boys. Online focus groups were conducted with 52 gay/bisexual male youth ages 14-17 years. Most gay/bisexual adolescent boys felt that their sexual orientation had an influence on their relationships with their parents and discussions about sex/dating. Although some felt that their relationships improved after coming out, a larger percentage reported that it put strain on their relationships. Discussions about sex/dating generally decreased after coming out, but some youth described positive conversations with their parents. Many reported that their parents struggled with whether or not to adapt parenting practices (e.g., rules about dating) after they came out. Youth consistently noted that parent-adolescent relationships and parenting practices depended on the adolescent's level of outness. Findings have important implications for refining HIV prevention programs for gay/bisexual adolescent boys, especially interventions that include parents.

  3. Stress and coping mediate relationships between contingent and global self-esteem and alcohol-related problems among college drinkers.

    Science.gov (United States)

    Tomaka, Joe; Morales-Monks, Stormy; Shamaley, Angelee Gigi

    2013-08-01

    This study examined the hypotheses that contingent self-esteem would be positively associated with alcohol-related problems and that global self-esteem would be negatively associated with such problems. It also examined the hypothesis that high stress and maladaptive coping would mediate these relationships. A sample of college students (n = 399) who were predominantly Hispanic (89%) completed measures of global and contingent self-esteem; stress and coping; and alcohol-related problems. Correlational and latent variable analyses indicated that contingent self-esteem positively related to alcohol-related problems, with maladaptive coping mediating this relationship. In contrast, global self-esteem negatively related to such problems, a relationship that was also mediated by maladaptive coping and stress. Overall, the results highlight the potentially harmful consequences of contingent self-worth and the adaptive nature of non-contingent self-esteem. They also demonstrate the important role that coping plays in mediating self-esteem's associations with alcohol-related problems. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Permeability computation on a REV with an immersed finite element method

    International Nuclear Information System (INIS)

    Laure, P.; Puaux, G.; Silva, L.; Vincent, M.

    2011-01-01

    An efficient method to compute permeability of fibrous media is presented. An immersed domain approach is used to represent the porous material at its microscopic scale and the flow motion is computed with a stabilized mixed finite element method. Therefore the Stokes equation is solved on the whole domain (including solid part) using a penalty method. The accuracy is controlled by refining the mesh around the solid-fluid interface defined by a level set function. Using homogenisation techniques, the permeability of a representative elementary volume (REV) is computed. The computed permeabilities of regular fibre packings are compared to classical analytical relations found in the bibliography.

  5. The relation between feedback perceptions and the supervisor-student relationship in master's thesis projects

    NARCIS (Netherlands)

    de Kleijn, Renske A M|info:eu-repo/dai/nl/323054080; Meijer, Paulien C.|info:eu-repo/dai/nl/176063765; Pilot, Albert|info:eu-repo/dai/nl/068350880; Brekelmans, Mieke|info:eu-repo/dai/nl/074625411

    2014-01-01

    Research supervision can be investigated from social-emotional and cognitive perspectives, but most studies include only one perspective. This study aims to understand the interplay between a social-emotional (supervisor-student relationship) and cognitive (feedback) perspective on the outcomes of

  6. Relationship of birth order and the marketing-related variable of materialism.

    Science.gov (United States)

    Zemanek, J E; Claxton, R P; Zemanek, W H

    2000-04-01

    The relationship between the birth order and materialism scores was investigated using materialism conceptualized as a consumer value. Data were collected from 275 alumni of a major southwestern university. The analysis indicated that first-borns in this sample scored significantly lower on materialism than younger siblings.

  7. The Relation of Cultural Context and Social Relationships to Career Development in Middle School

    Science.gov (United States)

    Howard, Kimberly A. S.; Ferrari, Lea; Nota, Laura; Solberg, V. Scott H.; Soresi, Salvatore

    2009-01-01

    This study examined the role of supportive relationships (i.e., family, teacher, and peer) and agency (i.e., self-efficacy, motivation, and goal-setting orientation) on three outcomes: academic grades, distress, and career decidedness. Data from 588 middle school youth from Northern (N=322) and Southern (N=266) Italy were analyzed using path…

  8. Exploring Relationships between Presage Variables of Florida Preservice Agricultural Education Teachers Related to Teaching Contextualized Mathematics

    Science.gov (United States)

    Stripling, Christopher T.; Roberts, T. Grady

    2013-01-01

    The purpose of this exploratory study was to investigate the relationships between mathematics ability, personal mathematics efficacy, mathematics teaching efficacy, personal teaching efficacy, and background characteristics of preservice agricultural education teachers. Data were collected for two years at the University of Florida. Fourteen…

  9. The Relation between Feedback Perceptions and the Supervisor-Student Relationship in Master's Thesis Projects

    Science.gov (United States)

    de Kleijn, Renske A. M.; Meijer, Paulien C.; Pilot, Albert; Brekelmans, Mieke

    2014-01-01

    Research supervision can be investigated from social-emotional and cognitive perspectives, but most studies include only one perspective. This study aims to understand the interplay between a social-emotional (supervisor-student relationship) and cognitive (feedback) perspective on the outcomes of master's thesis supervision in specific, by…

  10. The Relationships among Early Childhood Educators' Beliefs, Knowledge Bases, and Practices Related to Early Literacy.

    Science.gov (United States)

    Islam, Chhanda

    A study was conducted to determine and compare the literacy beliefs, knowledge bases, and practices of early childhood educators who espouse emergent literacy and reading readiness philosophies; to explore the relationship among beliefs, knowledge bases, and practices; and to examine the degree to which beliefs, knowledge bases, and practices were…

  11. Young Women's Phenomenological Sense of Father and Parental Marital Relationship and Their Relation to Paternal Loss.

    Science.gov (United States)

    Darlington, Susan

    The meaning fathers have in the lives of women as they are growing up was investigated. Women's perceptions of their fathers on several factors were measured to determine how these perceptions differed with father loss, cause and time of loss, perception of parental marital relationships, and presence of an older brother. Questionnaires were…

  12. From self to social relationships : An essentially relational perspective on social motivation

    NARCIS (Netherlands)

    van Zomeren, Martijn

    2016-01-01

    What is it that moves and motivates us in our lives? Martijn van Zomeren proposes social relationships are at the essence of this key question and, in a fascinating investigation into human motivation, he develops a novel and integrative psychological theory termed 'selvations theory'. The theory

  13. Work-related psychopathology: rates in different work activities and relationship between subjective perception of work distress and psychiatric disturbances.

    Science.gov (United States)

    Nolfe, Giovanni; Mancini, Paola; Mancusi, Riccardo; Zontini, Gemma; Nolfe, Giuseppe

    2014-01-01

    The link between work distress and negative mental health outcome is an emergent topic in the scientific literature. The studies that evaluated the risk of work-related psychopathologies in the different job sectors have obtained so far controversial and inconclusive results. The identification, by means of standardized evaluation tools, of the work activities at higher risk of poor mental health is a relevant target for the occupational psychiatry and medicine. To evaluate the relationship between the psychosocial work conditions and work related psychiatric disturbances and to verify the relationship between the higher pathogenic effect of work and specific job activities. A six-month diagnostic trial was conducted on 234 patients (35.4% women and 64.6% men). Psychiatric diagnoses were according to DSM-IV criteria; anxious and depressive dimensions were studied by means of Hamilton-Anxiety-Scale and Hamilton Scale for Depression; psychosocial work environments and bio-psycho-social features were measured by Naples-Questionnaire of Work Distress. Groups with higher and lower work-related pathogenesis were compared and their distribution among specific job activities was evaluated. Mood disorders were strongly linked to negative work environment. Patients with severe bullying obtained higher scores on Hamilton-Anxiety-Scale and Hamilton Scale for Depression than those with lower work-pathogenesis. The highest scores on Naples-Questionnaire of Work Distress were related to mood disorders, to poorer bio-psycho-social functioning and to higher work etiology. No significant relationship between work activities and work-related psychopathologies was found. Workplace bullying is predictive of work-related psychiatric disturbances with more severe clinical features and bio-psycho-social consequences. No significant differences were found about the relationship between work-related psychopathologies and work activities.

  14. Epinephrine and glucose modulate training-related CREB phosphorylation in old rats: relationships to age-related memory impairments.

    Science.gov (United States)

    Morris, Ken A; Gold, Paul E

    2013-02-01

    Epinephrine enhances memory in young adult rats, in part, by increasing blood glucose levels needed to modulate memory. In old rats, epinephrine is deficient at raising blood glucose levels and thus is only moderately effective at enhancing memory. In contrast, systemic glucose injections improve memory in old rats, with resulting memory performance equal to that of young rats. The diminished response of glucose to training in old rats may blunt downstream neurochemical and molecular mechanisms needed to upregulate memory processes. In the first experiment, young adult and old rats were trained on an inhibitory avoidance task with immediate post-training injections of aCSF or glucose into the dorsal hippocampus. Old rats had significant memory impairments compared to young rats 7 days after training. Intrahippocampal injections of glucose reversed age-related deficits, improving memory scores in old rats to values seen in young rats. A second experiment examined age-related changes in activation of the transcription factor CREB, which is widely implicated in memory formation and may act downstream of hormonal and metabolic signals. Activation was assessed in response to training with systemic injections of epinephrine and glucose at doses known to enhance memory. Young adult and old rats were trained on inhibitory avoidance with immediate post-training systemic injections of saline, epinephrine, or glucose. After training, old rats had significant impairments in CREB phosphorylation in area CA1 and the dentate gyrus region of the hippocampus, and in the basolateral and lateral amygdala. Epinephrine and glucose attenuated age-related deficits in CREB phosphorylation, but were more effective in the amygdala and hippocampus, respectively. Together, these results support the view that age-related changes in blood glucose responses to epinephrine contribute to memory impairments, which may be related to alterations in regional patterns of CREB phosphorylation. Copyright

  15. Musculoskeletal disorders among preschool teachers: analyzing the relationships among relational demands, work meaning, and intention to leave the job.

    Science.gov (United States)

    Converso, Daniela; Viotti, Sara; Sottimano, Ilaria; Cascio, Vincenza; Guidetti, Gloria

    2018-05-22

    Based on the conservation of resource (COR) theory by Hobfoll, the aim of the present study was to test whether the relationships among relational demands, work meaning, and intention to leave vary as a function of the presence of musculoskeletal disorders (MSDs). The study was cross-sectional and non-randomized. Analyses were carried out on a dataset consisting of 429 preschool teachers, who filled out a self-report questionnaire. Of them, 238 reported a MSD diagnosis and 191 were free form MSDs. As expected, among those who reported MSDs, relational demands were significantly associated to intention to leave, and this relationship was mediated by work meaning; moreover, among those free from MSDs, no significant paths among the three variables were found. In general, results showed that suffering from MSDs impairs workers' ability to face to relational demands, thus activating a spiral that encompasses diminished work meaning and intention to leave. Practical implications of results will be discussed in the paper.

  16. Examining the relationship between relative age, competition level, and dropout rates in male youth ice-hockey players.

    Science.gov (United States)

    Lemez, S; Baker, J; Horton, S; Wattie, N; Weir, P

    2014-12-01

    The relative age effect suggests that athletes born in the first two quartiles of a given selection year experience a selection advantage and therefore a greater opportunity for success. We describe two studies examining the relationship between relative age, competition level, and dropout rates of Ontario Minor Hockey Association male ice-hockey players from ages 10 to 15 years (n = 14 325). In Study 1, dropout was highest among players born in quartiles three and four [χ(2) (3) = 16.32, P < 0.05; w = 0.06], while Study 2 found dropped out players to have less movement between competition levels compared to retained players. This study confirms a relationship between relative age and dropout from ice-hockey and adds further depth to our understanding of this persistent phenomenon. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Radioisotope albumin flux measurement of microvascular lung permeability: an independent parameter in acute respiratory failure?

    International Nuclear Information System (INIS)

    Hoegerle, S.; Nitzsche, E.U.; Reinhardt, M.J.; Moser, E.; Benzing, A.; Geiger, K.; Schulte Moenting, J.

    2001-01-01

    Aim: To evaluate the extent to which single measurements of microvascular lung permeability may be relevant as an additional parameter in a heterogenous clinical patient collective with Acute Lung Injury (ALI) and Acute Respiratory Distress Syndrome (ARDS). Methods: In 36 patients with pneumonia (13), non pneumogenic sepsis (9) or trauma (14) meeting the consensus conference criteria of ALI or ARDS double-isotope protein flux measurements ( 51 Cr erythrocytes as intravascular tracer, Tc-99m human albumin as diffusible tracer) of microvascular lung permeability were performed using the Normalized Slope Index (NSI). The examination was to determine whether there is a relationship between the clinical diagnosis of ALI/ARDS, impaired permeability and clinical parameters, that is the underlying disease, oxygenation, duration of mechanical ventilation and mean pulmonary-artery pressure (PAP). Results: At the time of study, 25 patients presented with increased permeability (NSI > 1 x 10 -3 min -1 ) indicating an exudative stage of disease, and 11 patients with normal permeability. The permeability impairment correlated with the underlying disease (p > 0.05). With respect to survival, there was a negative correlation to PAP (p [de

  18. Role of platelets in maintenance of pulmonary vascular permeability to protein

    International Nuclear Information System (INIS)

    Lo, S.K.; Burhop, K.E.; Kaplan, J.E.; Malik, A.B.

    1988-01-01

    The authors examined the role of platelets in maintenance of pulmonary vascular integrity by inducing thrombocytopenia in sheep using antiplatelet serum (APS). A causal relationship between thrombocytopenia and increase in pulmonary vascular permeability was established by platelet repletion using platelet-rich plasma (PRP). Sheep were chronically instrumented and lung lymph fistulas prepared to monitor pulmonary lymph flow (Q lym ). A balloon catheter was positioned in the left atrium to assess pulmonary vascular permeability to protein after raising the left atrial pressure (P la ). Thrombocytopenia was maintained for 3 days by daily intramuscular APS injections. In studies using cultured bovine pulmonary artery endothelial monolayers, transendothelia permeability of 125 I-labeled albumin was reduced 50 and 95%, respectively, when 2.5 x 10 7 or 5 x 10 7 platelets were added onto endothelial monolayers. However, addition of 5 x 10 6 platelets or 5 x 10 7 red blood cells did not reduce endothelial monolayer albumin permeability. Results indicate that platelets are required for the maintenance of pulmonary vascular permeability. Reduction in permeability appears to involve an interaction of platelets with the endothelium

  19. The solubility-permeability interplay and oral drug formulation design: Two heads are better than one.

    Science.gov (United States)

    Dahan, Arik; Beig, Avital; Lindley, David; Miller, Jonathan M

    2016-06-01

    Poor aqueous solubility is a major challenge in today's biopharmaceutics. While solubility-enabling formulations can significantly increase the apparent solubility of the drug, the concomitant effect on the drug's apparent permeability has been largely overlooked. The mathematical equation to describe the membrane permeability of a drug comprises the membrane/aqueous partition coefficient, which in turn is dependent on the drug's apparent solubility in the GI milieu, suggesting that the solubility and the permeability are closely related, exhibit a certain interplay between them, and treating the one irrespectively of the other may be insufficient. In this article, an overview of this solubility-permeability interplay is provided, and the available data is analyzed in the context of the effort to maximize the overall drug exposure. Overall, depending on the type of solubility-permeability interplay, the permeability may decrease, remain unchanged, and even increase, in a way that may critically affect the formulation capability to improve the overall absorption. Therefore, an intelligent design of solubility-enabling formulation needs to consider both the solubility afforded by the formulation and the permeability in the new luminal environment resulting from the formulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Field-scale permeability and temperature of volcanic crust from borehole data: Campi Flegrei, southern Italy

    Science.gov (United States)

    Carlino, Stefano; Piochi, Monica; Tramelli, Anna; Mormone, Angela; Montanaro, Cristian; Scheu, Bettina; Klaus, Mayer

    2018-05-01

    We report combined measurements of petrophysical and geophysical parameters for a 501-m deep borehole located on the eastern side of the active Campi Flegrei caldera (Southern Italy), namely (i) in situ permeability by pumping tests, (ii) laboratory-determined permeability of the drill core, and (iii) thermal gradients by distributed fiber optic and thermocouple sensors. The borehole was drilled during the Campi Flegrei Deep Drilling Project (in the framework of the International Continental Scientific Drilling Program) and gives information on the least explored caldera sector down to pre-caldera deposits. The results allow comparative assessment of permeability obtained from both borehole (at depth between 422 a 501 m) and laboratory tests (on a core sampled at the same depth) for permeability values of 10-13 m2 (borehole test) and 10-15 m2 (laboratory test) confirm the scale-dependency of permeability at this site. Additional geochemical and petrophysical determinations (porosity, density, chemistry, mineralogy and texture), together with gas flow measurements, corroborate the hypothesis that discrepancies in the permeability values are likely related to in-situ fracturing. The continuous distributed temperature profile points to a thermal gradient of about 200 °C km-1. Our findings (i) indicate that scale-dependency of permeability has to be carefully considered in modelling of the hydrothermal system at Campi Flegrei, and (ii) improve the understanding of caldera dynamics for monitoring and mitigation of this very high volcanic risk area.

  1. The Interrelated Effects of Culture and Relationship Quality on the Relations Between Portuguese Exporters and Angolan Distributors

    Directory of Open Access Journals (Sweden)

    Gisela Alves

    2013-11-01

    Full Text Available The objective of this research is to investigate the role of the relationship quality and culture between Portuguese companies and their export market intermediaries in Angola. In particular, we aim to understand the importance that the quality of the relationship has and the role of cultures in export activities. In terms of methodology we opted for a qualitative analysis; we present the results of two case studies of Portuguese exporting companies and one case study on an Angolan intermediate. In general, the results show that the business relationships are influenced by trust, commitment, culture and similar values. As known, Angola was once a Portuguese colony, so communication is easy because these countries share some common cultural traits. Such factors will influence the trade relations between Portuguese exporters and their Angolan distributors.

  2. Relationship with environmental groups, the media and the public: aspects relating to environmental contaminations and safety

    International Nuclear Information System (INIS)

    Lacerda, J.R. de; Kepinski, A.; Almeida, M.J. de; Ferreira, A.L.V.

    1993-01-01

    In this article the Thermonuclear Directorate from FURNAS Centrais Eletricas S.A. looks at the brazilian situation and briefly reviews the relationship with environmental groups and the media. It them deals with nuclear power and public acceptance. In response, through their own programmes and with the support from governmental and non governmental initiatives a Nuclear Protection System Programme was organized. (B.C.A.). 01 fig, 04 tabs

  3. Phylogenetic relationships of geckos of the genus Nactus and their relatives (Squamata: Gekkonidae

    Directory of Open Access Journals (Sweden)

    Todd R. Jackman

    2008-05-01

    Full Text Available We employed nuclear and mitochondrial DNA sequence data to investigate relationships within the gekkonid genus Nactus and between Nactus and other gekkonid genera. Nuclear (RAG-1, PDC and mitochondrial (ND2 data provide strong support for conflicting patterns of relationship among bisexual New Guinean species of Nactus and the unisexual oceanic form N. pelagicus. This may be explained by an ancient mitochondrial introgression event between N. sphaerodactylodes and N. vankampeni, a recent selective sweep of mitochondrial DNA throughout N. vankampeni, and gene conflict stemming from the hybrid event that gave rise to N. pelagicus. Strong support from all data partitions is obtained for the sister group relationship of Nactus to a clade consisting of the Australian Heteronotia and the Southeast Asian Dixonius. Putative synapomorphies of the Nactus/Heteronotia/Dixonius clade include the reduction of the second phalanx of digit IV of the manus and the presence of regular rows of keeled (sometimes multicarinate dorsal tubercles on the dorsum. Nactus and Heteronotia both include parthenogenetic species formed via hybridogenesis. This is rare among geckos, and vertebrates in general, and at some level may also be synapomorphic. Dixonius is not known to have any all-female species, but “D. siamensis” consists of multiple chromosome “races” that mirror morphologically cryptic, but karyotypically distinct, species in the other two genera. The strong support for the Nactus/Heteronotia/Dixonius clade demonstrates that the leaf-toed digital morphology of Dixonius has evolved multiple times within the Gekkonidae and suggests that superficial digital morphology may be misleading with respect to gekkonid suprageneric relationships.

  4. Scale indicators of social exchange relationships: a comparison of relative content validity.

    Science.gov (United States)

    Colquitt, Jason A; Baer, Michael D; Long, David M; Halvorsen-Ganepola, Marie D K

    2014-07-01

    Although social exchange theory has become one of the most oft-evoked theories in industrial and organizational psychology, there remains no consensus about how to measure its key mechanism: social exchange relationships (Blau, 1964). Drawing on Cropanzano and Byrne's (2000) review of contemporary social exchange theorizing, we examined the content validity of perceived support, exchange quality, affective commitment, trust, and psychological contract fulfillment as indicators of social exchange relationships. We used Hinkin and Tracey's (1999) quantitative approach to content validation, which asks participants to rate the correspondence between scale items and definitions of intended (and unintended) constructs. Our results revealed that some of the most frequently utilized indicators of social exchange relationships--perceived support and exchange quality--were significantly less content valid than rarely used options like affect-based trust. Our results also revealed that 2 direct measures--Bernerth, Armenakis, Feild, Giles, and Walker's (2007) scale and a scale created for this study--were content valid. We discuss the implications of these results for future applications of social exchange theory.

  5. Long-term recall of social relationships related to addiction and HIV risk behaviors.

    Science.gov (United States)

    Stout, R L; Janssen, T; Braciszewski, J M; Vose-O'Neal, A

    2017-08-01

    Social relationships have been demonstrated as a key predictor of relapse among addicted persons and are likely to be important determinants of HIV risk behaviors also. However, the degree to which this population can reliably and consistently identify important people (IPs) in retrospect has been understudied. Using the modified Important People and Activities questionnaire, we investigated to what degree IPs were dropped, added, or retained, and whether data about individual IPs were reported accurately on 6- and 12-month follow up periods using a sample of 50 drug or alcohol abusing participants. We found that IPs were largely retained, and that those retained versus dropped/added differed by their reaction to participant alcohol/drug use, as well as frequency of contact. We further found that there were differences in reliability of data describing specific IPs. While both 6- and 12-month follow up periods led to reliabilities ranging from excellent to fair, we found poorer reliability on responses to recall of "frequency of contact" and "reactions to drinking", as well as "reactions to drug use". Future investigations of reliability of social relationships recalled retrospectively should attempt to examine possible systematic biases in addition to the reliability of specific IP data. More sophisticated studies are needed on factors associated with systematic variation in reporting of aspects of social relationships that are associated with addictions or HIV risk outcomes. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Gender Matters: The Relationship between Social Anxiety and Alcohol-Related Consequences

    OpenAIRE

    Schry, Amie R.; Norberg, Melissa M.; Maddox, Brenna B.; White, Susan W.

    2014-01-01

    BACKGROUND AND OBJECTIVES: Identification of risk factors for alcohol-related consequences is an important public health concern. Both gender and social anxiety have been associated with alcohol-related consequences broadly, but it is unknown whether these variables are differentially related to specific types of alcohol-related consequences for American college students. METHODS: In the present study, 573 undergraduate students (M(age) = 19.86 years, SD = 1.40; range 18 to 25; 68.9% female) ...

  7. Vaginismus and dyspareunia : Relationship with general and sex-related moral standards

    NARCIS (Netherlands)

    Borg, Charmaine; de Jong, Peter J.; Schultz, Willibrord Weijmar

    Introduction. Relatively strong adherence to conservative values and/or relatively strict sex-related moral standards logically restricts the sexual repertoire and will lower the threshold for experiencing negative emotions in a sexual context. In turn, this may generate withdrawal and avoidance

  8. Experimental Studies on Permeability of Intact and Singly Jointed Meta-Sedimentary Rocks Under Confining Pressure

    Science.gov (United States)

    Wong, Louis Ngai Yuen; Li, Diyuan; Liu, Gang

    2013-01-01

    Three different types of permeability tests were conducted on 23 intact and singly jointed rock specimens, which were cored from rock blocks collected from a rock cavern under construction in Singapore. The studied rock types belong to inter-bedded meta-sandstone and meta-siltstone with very low porosity and high uniaxial compressive strength. The transient pulse water flow method was employed to measure the permeability of intact meta-sandstone under a confining pressure up to 30 MPa. It showed that the magnitude order of meta-sandstone's intrinsic permeability is about 10-18 m2. The steady-state gas flow method was used to measure the permeability of both intact meta-siltstone and meta-sandstone in a triaxial cell under different confining pressures spanning from 2.5 to 10 MPa. The measured permeability of both rock types ranged from 10-21 to 10-20 m2. The influence of a single natural joint on the permeability of both rock types was studied by using the steady-state water flow method under different confining pressures spanning from 1.25 to 5.0 MPa, including loading and unloading phases. The measured permeability of both jointed rocks ranged from 10-13 to 10-11 m2, where the permeability of jointed meta-siltstone was usually slightly lower than that of jointed meta-sandstone. The permeability of jointed rocks decreases with increasing confining pressure, which can be well fitted by an empirical power law relationship between the permeability and confining pressure or effective pressure. The permeability of partly open cracked specimens is lower than that of open cracked specimens, but it is higher than that of the specimen with a dominant vein for the meta-sandstone under the same confining pressure. The permeability of open cracked rock specimens will partially recover during the unloading confining pressure process. The equivalent crack (joint) aperture is as narrow as a magnitude order of 10-6 m (1 μm) in the rock specimens under confining pressures

  9. The hydraulic permeability of blood clots as a function of fibrin and platelet density.

    Science.gov (United States)

    Wufsus, A R; Macera, N E; Neeves, K B

    2013-04-16

    Interstitial fluid flow within blood clots is a biophysical mechanism that regulates clot growth and dissolution. Assuming that a clot can be modeled as a porous medium, the physical property that dictates interstitial fluid flow is the hydraulic permeability. The objective of this study was to bound the possible values of the hydraulic permeability in clots formed in vivo and present relationships that can be used to estimate clot permeability as a function of composition. A series of clots with known densities of fibrin and platelets, the two major components of a clot, were formed under static conditions. The permeability was calculated by measuring the interstitial fluid velocity through the clots at a constant pressure gradient. Fibrin gels formed with a fiber volume fraction of 0.02-0.54 had permeabilities of 1.2 × 10(-1)-1.5 × 10(-4)μm(2). Platelet-rich clots with a platelet volume fraction of 0.01-0.61 and a fibrin volume fraction of 0.03 had permeabilities over a range of 1.1 × 10(-2)-1.5 × 10(-5)μm(2). The permeability of fibrin gels and of clots with platelet volume fraction of platelet volume fraction of >0.2 were modeled as a Brinkman medium of coarse solids (platelets) embedded in a mesh of fine fibers (fibrin). Our data suggest that the permeability of clots formed in vivo can vary by up to five orders of magnitude, with pore sizes that range from 4 to 350 nm. These findings have important implications for the transport of coagulation zymogens/enzymes in the interstitial spaces during clot formation, as well as the design of fibrinolytic drug delivery strategies. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  10. A Relational Model of Sexual Minority Mental and Physical Health: The Negative Effects of Shame on Relationships, Loneliness, and Health

    Science.gov (United States)

    Mereish, Ethan H.; Poteat, V. Paul

    2015-01-01

    Sexual minorities (e.g., lesbians, gay men, bisexual individuals) are at higher risk for mental and physical health disparities than heterosexuals, and some of these disparities relate to minority stressors such as discrimination. Yet, there is little research elucidating pathways that predict health or that promote resiliency among sexual minorities. Building on the minority stress model, the present study utilized relational cultural theory to situate sexual minority health within a relational framework. Specifically, the study tested mediators of the relationships between distal (i.e., discrimination, rejection, victimization) and proximal stressors (i.e., internalized homophobia, sexual orientation concealment) and psychological and physical distress for sexual minorities. Among 719 sexual minority adults, structural equation modeling analyses were used to test four models reflecting the mediating effects of shame, poorer relationships with a close peer and the LGBT community, and loneliness on the associations between minority stressors and psychological distress (i.e., depression and anxiety) and physical distress (i.e., distressing physical symptoms). As hypothesized, the associations between distal and proximal minority stressors and distress were mediated by shame, poorer relationships with a close peer and the LGBT community, and loneliness. Findings underscore the possible relational and interpersonal mechanisms by which sexual minority stressors lead to psychological and physical distress. PMID:26010289

  11. Staying on Task: Age-Related Changes in the Relationship Between Executive Functioning and Response Time Consistency.

    Science.gov (United States)

    Vasquez, Brandon P; Binns, Malcolm A; Anderson, Nicole D

    2016-03-01

    Little is known about the relationship of executive functioning with age-related increases in response time (RT) distribution indices (intraindividual standard deviation [ISD], and ex-Gaussian parameters mu, sigma, tau). The goals of this study were to (a) replicate findings of age-related changes in response time distribution indices during an engaging touch-screen RT task and (b) investigate age-related changes in the relationship between executive functioning and RT distribution indices. Healthy adults (24 young [aged 18-30], 24 young-old [aged 65-74], and 24 old-old [aged 75-85]) completed a touch-screen attention task and a battery of neuropsychological tests. The relationships between RT performance and executive functions were examined with structural equation modeling (SEM). ISD, mu, and tau, but not sigma, increased with age. SEM revealed tau as the most salient RT index associated with neuropsychological measures of executive functioning. Further analysis demonstrated that correlations between tau and a weighted executive function composite were significant only in the old-old group. Our results replicate findings of greater RT inconsistency in older adults and reveal that executive functioning is related to tau in adults aged 75-85. These results support literature identifying tau as a marker of cognitive control, which deteriorates in old age. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. A relational model of sexual minority mental and physical health: The negative effects of shame on relationships, loneliness, and health.

    Science.gov (United States)

    Mereish, Ethan H; Poteat, V Paul

    2015-07-01

    Sexual minorities (e.g., lesbians, gay men, bisexual individuals) are at an increased risk for poorer mental and physical health outcomes than heterosexuals, and some of these health disparities relate to minority stressors such as discrimination. Yet, there is little research elucidating pathways that predict health or that promote resiliency among sexual minorities. Building on the minority stress model, the present study utilized relational cultural theory to situate sexual minority health within a relational framework. Specifically, the study tested mediators of the relationships between distal (i.e., discrimination, rejection, victimization) and proximal stressors (i.e., internalized homophobia, sexual orientation concealment) and psychological and physical distress for sexual minorities. Among 719 sexual minority adults, structural equation modeling analyses were used to test 4 models reflecting the mediating effects of shame, poorer relationships with a close peer and the lesbian/gay/bisexual/transgender (LGBT) community, and loneliness on the associations between minority stressors and psychological distress (i.e., depression and anxiety) and physical distress (i.e., distressing physical symptoms). As hypothesized, the associations between distal and proximal minority stressors and distress were mediated by shame, poorer relationships with a close peer and the LGBT community, and loneliness. Findings underscore the possible relational and interpersonal mechanisms by which sexual minority stressors lead to psychological and physical distress. (c) 2015 APA, all rights reserved).