attachment rate coefficient: Topics by Science.gov

Sample records for attachment rate coefficient

Bacteriophage PRD1 batch experiments to study attachment, detachment and inactivation processes

NASA Astrophysics Data System (ADS)

Sadeghi, Gholamreza; Schijven, Jack F.; Behrends, Thilo; Hassanizadeh, S. Majid; van Genuchten, Martinus Th.

2013-09-01

Knowledge of virus removal in subsurface environments is pivotal for assessing the risk of viral contamination of water resources and developing appropriate protection measures. Columns packed with sand are frequently used to quantify attachment, detachment and inactivation rates of viruses. Since column transport experiments are very laborious, a common alternative is to perform batch experiments where usually one or two measurements are done assuming equilibrium is reached. It is also possible to perform kinetic batch experiments. In that case, however, it is necessary to monitor changes in the concentration with time. This means that kinetic batch experiments will be almost as laborious as column experiments. Moreover, attachment and detachment rate coefficients derived from batch experiments may differ from those determined using column experiments. The aim of this study was to determine the utility of kinetic batch experiments and investigate the effects of different designs of the batch experiments on estimated attachment, detachment and inactivation rate coefficients. The experiments involved various combinations of container size, sand-water ratio, and mixing method (i.e., rolling or tumbling by pivoting the tubes around their horizontal or vertical axes, respectively). Batch experiments were conducted with clean quartz sand, water at pH 7 and ionic strength of 20 mM, and using the bacteriophage PRD1 as a model virus. Values of attachment, detachment and inactivation rate coefficients were found by fitting an analytical solution of the kinetic model equations to the data. Attachment rate coefficients were found to be systematically higher under tumbling than under rolling conditions because of better mixing and more efficient contact of phages with the surfaces of the sand grains. In both mixing methods, more sand in the container yielded higher attachment rate coefficients. A linear increase in the detachment rate coefficient was observed with increased solid-water ratio using tumbling method. Given the differences in the attachment rate coefficients, and assuming the same sticking efficiencies since chemical conditions of the batch and column experiments were the same, our results show that collision efficiencies of batch experiments are not the same as those of column experiments. Upscaling of the attachment rate from batch to column experiments hence requires proper understanding of the mixing conditions. Because batch experiments, in which the kinetics are monitored, are as laborious as column experiments, there seems to be no major advantage in performing batch instead of column experiments.
Rate coefficients for dissociative attachment and resonant electron-impact dissociation involving vibrationally excited O{sub 2} molecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laporta, V.; Celiberto, R.; Tennyson, J.

Rate coefficients for dissociative electron attachment and electron-impact dissociation processes, involving vibrationally excited molecular oxygen, are presented. Analytical fits of the calculated numerical data, useful in the applications, are also provided.
Bacteriophage PRD1 batch experiments to study attachment, detachment and inactivation processes.

PubMed

Sadeghi, Gholamreza; Schijven, Jack F; Behrends, Thilo; Hassanizadeh, S Majid; van Genuchten, Martinus Th

2013-09-01

Knowledge of virus removal in subsurface environments is pivotal for assessing the risk of viral contamination of water resources and developing appropriate protection measures. Columns packed with sand are frequently used to quantify attachment, detachment and inactivation rates of viruses. Since column transport experiments are very laborious, a common alternative is to perform batch experiments where usually one or two measurements are done assuming equilibrium is reached. It is also possible to perform kinetic batch experiments. In that case, however, it is necessary to monitor changes in the concentration with time. This means that kinetic batch experiments will be almost as laborious as column experiments. Moreover, attachment and detachment rate coefficients derived from batch experiments may differ from those determined using column experiments. The aim of this study was to determine the utility of kinetic batch experiments and investigate the effects of different designs of the batch experiments on estimated attachment, detachment and inactivation rate coefficients. The experiments involved various combinations of container size, sand-water ratio, and mixing method (i.e., rolling or tumbling by pivoting the tubes around their horizontal or vertical axes, respectively). Batch experiments were conducted with clean quartz sand, water at pH 7 and ionic strength of 20 mM, and using the bacteriophage PRD1 as a model virus. Values of attachment, detachment and inactivation rate coefficients were found by fitting an analytical solution of the kinetic model equations to the data. Attachment rate coefficients were found to be systematically higher under tumbling than under rolling conditions because of better mixing and more efficient contact of phages with the surfaces of the sand grains. In both mixing methods, more sand in the container yielded higher attachment rate coefficients. A linear increase in the detachment rate coefficient was observed with increased solid-water ratio using tumbling method. Given the differences in the attachment rate coefficients, and assuming the same sticking efficiencies since chemical conditions of the batch and column experiments were the same, our results show that collision efficiencies of batch experiments are not the same as those of column experiments. Upscaling of the attachment rate from batch to column experiments hence requires proper understanding of the mixing conditions. Because batch experiments, in which the kinetics are monitored, are as laborious as column experiments, there seems to be no major advantage in performing batch instead of column experiments. Copyright © 2013 Elsevier B.V. All rights reserved.
On the validity of the Arrhenius equation for electron attachment rate coefficients.

PubMed

Fabrikant, Ilya I; Hotop, Hartmut

2008-03-28

The validity of the Arrhenius equation for dissociative electron attachment rate coefficients is investigated. A general analysis allows us to obtain estimates of the upper temperature bound for the range of validity of the Arrhenius equation in the endothermic case and both lower and upper bounds in the exothermic case with a reaction barrier. The results of the general discussion are illustrated by numerical examples whereby the rate coefficient, as a function of temperature for dissociative electron attachment, is calculated using the resonance R-matrix theory. In the endothermic case, the activation energy in the Arrhenius equation is close to the threshold energy, whereas in the case of exothermic reactions with an intermediate barrier, the activation energy is found to be substantially lower than the barrier height.
Counselors' attachment anxiety and avoidance and the congruence in clients' and therapists' working alliance ratings.

PubMed

Kivlighan, Dennis M; Marmarosh, Cheri L

2018-07-01

To determine how counselors' attachment anxiety and avoidance related to congruence between counselors' and clients' Working alliance (WA) ratings. Congruence strength was defined as the regression coefficient for clients' WA ratings predicting counselors' WA ratings. Directional bias was defined as the difference in level between counselors' and clients' WA ratings. Twenty-seven graduate student counselors completed an attachment measure and they and their 64 clients completed a measure of WA early in therapy. The truth-and-bias analysis was adapted to analyze the data. As hypothesized counselors' WA ratings were significantly and positively related to clients' WA ratings. Also as hypothesized, counselors' WA ratings were significantly lower than their clients' WA ratings (directional bias). Increasing counselor attachment anxiety was related to increasing negative directional bias; as counselors' attachment anxiety increased the difference between counselors and clients WA ratings became more negative. There was a significant interaction between counselor attachment anxiety and congruence strength in predicting counselor WA ratings. There was a stronger relationship between client WA ratings and counselor WA ratings for counselors low versus high in attachment anxiety. Counselors' attachment anxiety is realted to their ability to accurately percieve their clients' WA.
Temperature dependency of virus and nanoparticle transport and retention in saturated porous media

USDA-ARS?s Scientific Manuscript database

The influence of temperature (4 and 20 °C) on virus and nanoparticle attachment in columns packed with quartz sand was studied under various physiochemical conditions. Fitted values of the attachment rate coefficient (katt) and the solid fraction that contributed to attachment (Sf) were found to be...
Permeability and kinetic coefficients for mesoscale BCF surface step dynamics: Discrete two-dimensional deposition-diffusion equation analysis

DOE PAGES

Zhao, Renjie; Evans, James W.; Oliveira, Tiago J.

2016-04-08

Here, a discrete version of deposition-diffusion equations appropriate for description of step flow on a vicinal surface is analyzed for a two-dimensional grid of adsorption sites representing the stepped surface and explicitly incorporating kinks along the step edges. Model energetics and kinetics appropriately account for binding of adatoms at steps and kinks, distinct terrace and edge diffusion rates, and possible additional barriers for attachment to steps. Analysis of adatom attachment fluxes as well as limiting values of adatom densities at step edges for nonuniform deposition scenarios allows determination of both permeability and kinetic coefficients. Behavior of these quantities is assessedmore » as a function of key system parameters including kink density, step attachment barriers, and the step edge diffusion rate.« less
Permeability and kinetic coefficients for mesoscale BCF surface step dynamics: Discrete two-dimensional deposition-diffusion equation analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Renjie; Evans, James W.; Oliveira, Tiago J.

Here, a discrete version of deposition-diffusion equations appropriate for description of step flow on a vicinal surface is analyzed for a two-dimensional grid of adsorption sites representing the stepped surface and explicitly incorporating kinks along the step edges. Model energetics and kinetics appropriately account for binding of adatoms at steps and kinks, distinct terrace and edge diffusion rates, and possible additional barriers for attachment to steps. Analysis of adatom attachment fluxes as well as limiting values of adatom densities at step edges for nonuniform deposition scenarios allows determination of both permeability and kinetic coefficients. Behavior of these quantities is assessedmore » as a function of key system parameters including kink density, step attachment barriers, and the step edge diffusion rate.« less
Structures for attaching or sealing a space between components having different coefficients or rates of thermal expansion

DOEpatents

Corman, Gregory Scot; Dean, Anthony John; Tognarelli, Leonardo; Pecchioli, Mario

2005-06-28

A structure for attaching together or sealing a space between a first component and a second component that have different rates or amounts of dimensional change upon being exposed to temperatures other than ambient temperature. The structure comprises a first attachment structure associated with the first component that slidably engages a second attachment structure associated with the second component, thereby allowing for an independent floating movement of the second component relative to the first component. The structure can comprise split rings, laminar rings, or multiple split rings.
Direct measurement of the thermal rate coefficient for electron attachment to ozone in the gas phase, 300-550 K: implications for the ionosphere.

PubMed

Van Doren, Jane M; Miller, Thomas M; Williams, Skip; Viggiano, A A

2003-11-28

Attachment of thermal electrons to O3 was studied in 133 Pa He between 300-550 K; the process is extremely inefficient. The rate coefficient increases sharply with temperature from 0.9 to 5 x 10(-11) cm(3) s(-1) (+/-30%) and comparison to kinetic energy measurements suggests internal energy can drive the reaction. These determinations account for competing processes of diffusion, recombination, and electron detachment reactions, and imply that no significant zero-energy resonance cross section exists, contradicting recent electron-beam results that call for substantial revision of ionospheric models.
Electron attachment and positive ion chemistry of monohydrogenated fluorocarbon radicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiens, Justin P.; Shuman, Nicholas S.; Miller, Thomas M.

Rate coefficients and product branching fractions for electron attachment and for reaction with Ar{sup +} are measured over the temperature range 300–585 K for three monohydrogenated fluorocarbon (HFC) radicals (CF{sub 3}CHF, CHF{sub 2}CF{sub 2}, and CF{sub 3}CHFCF{sub 2}), as well as their five closed-shell precursors (1-HC{sub 2}F{sub 4}I, 2-HC{sub 2}F{sub 4}I, 2-HC{sub 2}F{sub 4}Br, 1-HC{sub 3}F{sub 6}I, 2-HC{sub 3}F{sub 6}Br). Attachment to the HFC radicals is always fairly inefficient (between 0.1% and 10% of the Vogt–Wannier capture rate), but generally faster than attachment to analogous perfluorinated carbon radicals. The primary products in all cases are HF-loss to yield C{sub n}F{submore » m−1}{sup −} anions, with only a minor branching to F{sup −} product. In all cases the temperature dependences are weak. Attachment to the precursor halocarbons is near the capture rate with a slight negative temperature dependence in all cases except for 2-HC{sub 2}F{sub 4}Br, which is ∼10% efficient at 300 K and becomes more efficient, approaching the capture rate at higher temperatures. All attachment kinetics are successfully reproduced using a kinetic modeling approach. Reaction of the HFC radicals with Ar{sup +} proceeds at or near the calculated collisional rate coefficient in all cases, yielding a wide variety of product ions.« less
Evaluating the effects of variable water chemistry on bacterial transport during infiltration.

PubMed

Zhang, Haibo; Nordin, Nahjan Amer; Olson, Mira S

2013-07-01

Bacterial infiltration through the subsurface has been studied experimentally under different conditions of interest and is dependent on a variety of physical, chemical and biological factors. However, most bacterial transport studies fail to adequately represent the complex processes occurring in natural systems. Bacteria are frequently detected in stormwater runoff, and may present risk of microbial contamination during stormwater recharge into groundwater. Mixing of stormwater runoff with groundwater during infiltration results in changes in local solution chemistry, which may lead to changes in both bacterial and collector surface properties and subsequent bacterial attachment rates. This study focuses on quantifying changes in bacterial transport behavior under variable solution chemistry, and on comparing the influences of chemical variability and physical variability on bacterial attachment rates. Bacterial attachment rate at the soil-water interface was predicted analytically using a combined rate equation, which varies temporally and spatially with respect to changes in solution chemistry. Two-phase Monte Carlo analysis was conducted and an overall input-output correlation coefficient was calculated to quantitatively describe the importance of physiochemical variation on the estimates of attachment rate. Among physical variables, soil particle size has the highest correlation coefficient, followed by porosity of the soil media, bacterial size and flow velocity. Among chemical variables, ionic strength has the highest correlation coefficient. A semi-reactive microbial transport model was developed within HP1 (HYDRUS1D-PHREEQC) and applied to column transport experiments with constant and variable solution chemistries. Bacterial attachment rates varied from 9.10×10(-3)min(-1) to 3.71×10(-3)min(-1) due to mixing of synthetic stormwater (SSW) with artificial groundwater (AGW), while bacterial attachment remained constant at 9.10×10(-3)min(-1) in a constant solution chemistry (AGW only). The model matched observed bacterial breakthrough curves well. Although limitations exist in the application of a semi-reactive microbial transport model, this method represents one step towards a more realistic model of bacterial transport in complex microbial-water-soil systems. Copyright © 2013 Elsevier B.V. All rights reserved.
Non-steady state simulation of BOM removal in drinking water biofilters: model development.

PubMed

Hozalski, R M; Bouwer, E J

2001-01-01

A numerical model was developed to simulate the non-steady-state behavior of biologically-active filters used for drinking water treatment. The biofilter simulation model called "BIOFILT" simulates the substrate (biodegradable organic matter or BOM) and biomass (both attached and suspended) profiles in a biofilter as a function of time. One of the innovative features of BIOFILT compared to previous biofilm models is the ability to simulate the effects of a sudden loss in attached biomass or biofilm due to filter backwash on substrate removal performance. A sensitivity analysis of the model input parameters indicated that the model simulations were most sensitive to the values of parameters that controlled substrate degradation and biofilm growth and accumulation including the substrate diffusion coefficient, the maximum rate of substrate degradation, the microbial yield coefficient, and a dimensionless shear loss coefficient. Variation of the hydraulic loading rate or other parameters that controlled the deposition of biomass via filtration did not significantly impact the simulation results.
Thermal electron attachment to chlorinated alkenes in the gas phase

NASA Astrophysics Data System (ADS)

Wnorowski, K.; Wnorowska, J.; Michalczuk, B.; Jówko, A.; Barszczewska, W.

2017-01-01

This paper reports the measurements of the rate coefficients and the activation energies of the electron capture processes with various chlorinated alkenes. The electron attachment processes in the mixtures of chlorinated alkenes with carbon dioxide have been investigated using a Pulsed Townsend technique. This study has been performed in the temperature range (298-378) K. The obtained rate coefficients more or less depended on temperature in accordance to Arrhenius equation. The activation energies (Ea's) were determined from the fit to the experimental data points with function ln(k) = ln(A) - Ea/kBT. The rate coefficients at 298 K were equal to 1.0 × 10-10 cm3 s-1, 2.2 × 10-11 cm3 s-1, 1.6 × 10-9 cm3 s-1, 4.4 × 10-8 cm3 s-1, 2.9 × 10-12 cm3 s-1 and 7.3 × 10-12 cm3 s-1 and activation energies were: 0.27 eV, 0.26 eV, 0.25 eV, 0.21 eV, 0.55 eV and 0.42 eV, for trans-1,2-dichloroethylene, cis-1,2-dichloroethylene, trichloroethylene, tetrachloroethylene, 2-chloropropene, 3-chloropropene respectively.
Colloid Transport in Saturated Porous Media: Elimination of Attachment Efficiency in a New Colloid Transport Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Landkamer, Lee L.; Harvey, Ronald W.; Scheibe, Timothy D.

A new colloid transport model is introduced that is conceptually simple but captures the essential features of complicated attachment and detachment behavior of colloids when conditions of secondary minimum attachment exist. This model eliminates the empirical concept of collision efficiency; the attachment rate is computed directly from colloid filtration theory. Also, a new paradigm for colloid detachment based on colloid population heterogeneity is introduced. Assuming the dispersion coefficient can be estimated from tracer behavior, this model has only two fitting parameters: (1) the fraction of colloids that attach irreversibly and (2) the rate at which reversibly attached colloids leave themore » surface. These two parameters were correlated to physical parameters that control colloid transport such as the depth of the secondary minimum and pore water velocity. Given this correlation, the model serves as a heuristic tool for exploring the influence of physical parameters such as surface potential and fluid velocity on colloid transport. This model can be extended to heterogeneous systems characterized by both primary and secondary minimum deposition by simply increasing the fraction of colloids that attach irreversibly.« less
On the accuracy of the rate coefficients used in plasma fluid models for breakdown in air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kourtzanidis, Konstantinos, E-mail: kkourt@utexas.edu; Raja, Laxminarayan L., E-mail: lraja@mail.utexas.edu

2016-07-15

The electrical breakdown of air depends on the balance between creation and loss of charged particles. In fluid models, datasets of the rate coefficients used are obtained either from fits to experimental data or by solutions of the Boltzmann equation. Here, we study the accuracy of the commonly used models for ionization and attachment frequencies and their impact on the prediction of the breakdown threshold for air. We show that large errors can occur depending on the model and propose the most accurate dataset available for modeling of air breakdown phenomena.
Evaporator film coefficients of grooved heat pipes

NASA Technical Reports Server (NTRS)

Kamotani, Y.

1978-01-01

The heat transfer rate in the meniscus attachment region of a grooved heat pipe evaporator is studied theoretically. The analysis shows that the evaporation takes place mainly in the region where the liquid changes its shape sharply. However, comparisons with available heat transfer data indicate that the heat transfer rate in the meniscus varying region is substantially reduced probably due to groove wall surface roughness.
Theoretical study of radiative electron attachment to CN, C{sub 2}H, and C{sub 4}H radicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Douguet, Nicolas; Fonseca dos Santos, S.; Orel, Ann E.

A first-principle theoretical approach to study the process of radiative electron attachment is developed and applied to the negative molecular ions CN{sup −}, C{sub 4}H{sup −}, and C{sub 2}H{sup −}. Among these anions, the first two have already been observed in the interstellar space. Cross sections and rate coefficients for formation of these ions by direct radiative electron attachment to the corresponding neutral radicals are calculated. For the CN molecule, we also considered the indirect pathway, in which the electron is initially captured through non-Born-Oppenheimer coupling into a vibrationally resonant excited state of the anion, which then stabilizes by radiativemore » decay. We have shown that the contribution of the indirect pathway to the formation of CN{sup −} is negligible in comparison to the direct mechanism. The obtained rate coefficients for the direct mechanism at 30 K are 7 × 10{sup −16} cm{sup 3}/s for CN{sup −}, 7 × 10{sup −17} cm{sup 3}/s for C{sub 2}H{sup −}, and 2 × 10{sup −16} cm{sup 3}/s for C{sub 4}H{sup −}. These rates weakly depend on temperature between 10 K and 100 K. The validity of our calculations is verified by comparing the present theoretical results with data from recent photodetachment experiments.« less
Bacteriophage adsorption during transport through porous media: Chemical perturbations and reversibility

USGS Publications Warehouse

Bales, R.C.; Hinkle, S.R.; Kroeger, T.W.; Stocking, K.; Gerba, C.P.

1991-01-01

In a series of seven column experiments, attachment of the bacteriophage PRD-1 and MS-2 to silica beads at pH's 5.0-5.5 was at least partially reversible; however, release of attached phage was slow and breakthrough curves exhibited significant tailing. Rate coefficients for attachment and detachment were on the order of 10-4 and 10-6-10-4 s-1, respectively. Corresponding time scales were hours for attachment and days for detachment. The sticking efficiency (??) for phage attachment was near 0.01. The rate of phage release was enhanced by raising pH and introducing surface-active chemical species, illustrating the importance of chemical perturbations in promoting biocolloid transport. In a series of batch experiments, MS-2 adsorbed strongly to a hydrophobic surface, octadecyltrichlorosilane-bonded silica, at both pH's 5 and 7. Adsorption to the unbonded silica at pH 5 was linear, but was 2.5 (with Ca2+) to 0.25% (without Ca2+) of that to the bonded surface. Neither MS-2 nor PRD-1 adsorbed to unbonded silica at pH 7. Hydrophobic effects appear to be important for adsorption of even relatively hydrophilic biocolloids. ?? 1991 American Chemical Society.
Low-Energy Electron Interactions with CF_4

NASA Astrophysics Data System (ADS)

Christophorou, Loucas G.; Olthoff, James K.; Rao, M. V. V. S.

1996-10-01

Carbon tetrafluoride is one of the most widely used components of feed gas mixtures employed for a variety of plasma assisted materials processing applications. In this presentation, we synthesize and assess the available information on the cross sections and rate coefficients of collisional interations of CF4 with electrons.(L. G. Christophorou, J. K. Olthoff, and M.V. V. S. Rao, J. Phys. Chem. Ref. Data, submitted (May 1996)) A ``recommended'' data set is presented, based upon available data for: (i) cross sections for electron scattering (total, elastic, momentum, differential, inelastic), electron impact ionization (total and partial), electron impact dissociation, and electron attachment; and (ii) coefficients for electron transport, electron attachment, and electron impact ionization. -Research sponsored in part by the U.S. Air Force Wright Laboratory under contract F33615-96-C-2600 with the University of Tennessee. Also, Department of Physics, The University of Tennessee, Knoxville, TN.

Modeling online social signed networks

NASA Astrophysics Data System (ADS)

Li, Le; Gu, Ke; Zeng, An; Fan, Ying; Di, Zengru

2018-04-01

People's online rating behavior can be modeled by user-object bipartite networks directly. However, few works have been devoted to reveal the hidden relations between users, especially from the perspective of signed networks. We analyze the signed monopartite networks projected by the signed user-object bipartite networks, finding that the networks are highly clustered with obvious community structure. Interestingly, the positive clustering coefficient is remarkably higher than the negative clustering coefficient. Then, a Signed Growing Network model (SGN) based on local preferential attachment is proposed to generate a user's signed network that has community structure and high positive clustering coefficient. Other structural properties of the modeled networks are also found to be similar to the empirical networks.
Measurement of the Electron Density and the Attachment Rate Coefficient in Silane/Helium Discharges.

DTIC Science & Technology

1986-09-01

materials -- in this case hydrogenated amorphous silicon . One of the biggest problems in such a task is the fact that the discharge creates complex radicals...electron density is enhanced -- even on a time-averaged basis, and the silicon deposition rate is also increased. The physical process for the density...etching and deposition of semiconductor materials. Plasma etching (also known as dry etching) Of silicon using flourine bearing gases has made it possible
H- photodetachment and radiative attachment for astrophysical applications

NASA Astrophysics Data System (ADS)

McLaughlin, B. M.; Stancil, P. C.; Sadeghpour, H. R.; Forrey, R. C.

2017-06-01

We combine R-matrix calculations, asymptotic relations, and comparison to available experimental data to construct an H- photodetachment cross section reliable over a large range of photon energies and take into account the series of auto-detaching shape and Feshbach resonances between 10.92 and 14.35 eV. The accuracy of the cross section is controlled by ensuring that it satisfies all known oscillator strength sum rules, including contributions from the resonances and single-photon double-electron photodetachment. From the resulting recommended cross section, spontaneous and stimulated radiative attachment rate coefficients are obtained. Photodetachment rates are also computed for the standard interstellar radiation field, in diffuse and dense interstellar clouds, for blackbody radiation, and for high redshift distortion photons in the recombination epoch. Implications are investigated for these astrophysical radiation fields and epochs.
Effect of Aperture Field Variability, Flow Rate, and Ionic Strength on Colloid Transport in Single Fractures: Laboratory-Scale Experiments and Numerical Simulation

NASA Astrophysics Data System (ADS)

Zheng, Q.; Dickson, S.; Guo, Y.

2007-12-01

A good understanding of the physico-chemical processes (i.e., advection, dispersion, attachment/detachment, straining, sedimentation etc.) governing colloid transport in fractured media is imperative in order to develop appropriate bioremediation and/or bioaugmentation strategies for contaminated fractured aquifers, form management plans for groundwater resources to prevent pathogen contamination, and identify suitable radioactive waste disposal sites. However, research in this field is still in its infancy due to the complex heterogeneous nature of fractured media and the resulting difficulty in characterizing this media. The goal of this research is to investigate the effects of aperture field variability, flow rate and ionic strength on colloid transport processes in well characterized single fractures. A combination of laboratory-scale experiments, numerical simulations, and imaging techniques were employed to achieve this goal. Transparent replicas were cast from natural rock fractures, and a light transmission technique was employed to measure their aperture fields directly. The surface properties of the synthetic fractures were characterized by measuring the zeta-potential under different ionic strengths. A 33 (3 increased to the power of 3) factorial experiment was implemented to investigate the influence of aperture field variability, flow rate, and ionic strength on different colloid transport processes in the laboratory-scale fractures, specifically dispersion and attachment/detachment. A fluorescent stain technique was employed to photograph the colloid transport processes, and an analytical solution to the one-dimensional transport equation was fit to the colloid breakthrough curves to calculate the average transport velocity, dispersion coefficient, and attachment/detachment coefficient. The Reynolds equation was solved to obtain the flow field in the measured aperture fields, and the random walk particle tracking technique was employed to model the colloid transport experiments. The images clearly show the development of preferential pathways for colloid transport in the different aperture fields and under different flow conditions. Additionally, a correlation between colloid deposition and fracture wall topography was identified. This presentation will demonstrate (1) differential transport between colloid and solute in single fractures, and the relationship between differential transport and aperture field statistics; (2) the relationship between the colloid dispersion coefficient and aperture field statistics; and (3) the relationship between attachment/detachment, aperture field statistics, fracture wall topography, flow rate, and ionic strength. In addition, this presentation will provide insight into the application of the random walk particle tracking technique for modeling colloid transport in variable-aperture fractures.
Humic acid transport in saturated porous media: influence of flow velocity and influent concentration.

PubMed

Wei, Xiaorong; Shao, Mingan; Du, Lina; Horton, Robert

2014-12-01

Understanding the transport of humic acids (HAs) in porous media can provide important and practical evidence needed for accurate prediction of organic/inorganic contaminant transport in different environmental media and interfaces. A series of column transport experiments was conducted to evaluate the transport of HA in different porous media at different flow velocities and influent HA concentrations. Low flow velocity and influent concentration were found to favor the adsorption and deposition of HA onto sand grains packed into columns and to give higher equilibrium distribution coefficients and deposition rate coefficients, which resulted in an increased fraction of HA being retained in columns. Consequently, retardation factors were increased and the transport of HA through the columns was delayed. These results suggest that the transport of HA in porous media is primarily controlled by the attachment of HA to the solid matrix. Accordingly, this attachment should be considered in studies of HA behavior in porous media. Copyright © 2014. Published by Elsevier B.V.
Increasing positive ion number densities below the peak of ion-electron pair production in Titan's ionosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vigren, E.; Galand, M.; Shebanits, O.

2014-05-01

We combine derived ion-electron pair formation rates with Cassini Radio Plasma Wave Science Langmuir Probe measurements of electron and positive ion number densities in Titan's sunlit ionosphere. We show that positive ion number densities in Titan's sunlit ionosphere can increase toward significantly lower altitudes than the peak of ion-electron pair formation despite that the effective ion-electron recombination coefficient increases. This is explained by the increased mixing ratios of negative ions, which are formed by electron attachment to neutrals. While such a process acts as a sink for free electrons, the positive ions become longer-lived as the rate coefficients for ion-anionmore » neutralization reactions are smaller than those for ion-electron dissociative recombination reactions.« less
Relationship between parent–infant attachment and parental satisfaction with supportive nursing care

PubMed Central

Ghadery-Sefat, Akram; Abdeyazdan, Zahra; Badiee, Zohreh; Zargham-Boroujeni, Ali

2016-01-01

Background: Parent–infant attachment is an important factor in accepting parenting role, accelerating infant survival, and adjusting to the environment outside the uterus. Since family supportive interventions can strengthen the parent–infant caring relationship, this study sought to investigate the relationship between mother–infant attachment and satisfaction of the mothers with the supportive nursing care received in the neonatal intensive care unit (NICU). Materials and Methods: In this descriptive–correlational study, 210 mothers with premature infants who were hospitalized in the NICUs affiliated to Isfahan Medical University hospitals took part. The data were collected via Maternal Postnatal Attachment Scale and researcher's self-tailored questionnaire based on Nurse Parent Support Tool. Pearson correlation coefficient and multiple linear regressions were used to analyze the collected data. Results: The results showed that the overall score of mother–infant attachment and the overall score of maternal satisfaction correlated with a correlation coefficient of r = 0.195. Also, the overall score of mother–infant attachment and mothers’ satisfaction scores in the emotional, communicative-informative, and self-confidence domains correlated with correlation coefficients of r = 0.182, r = 0.0.189, and r = 0.0.304, respectively. The results of multiple regression analysis revealed that about 15% of changes in the dependent variable (mother–infant attachment) could be explained by different dimensions of mothers’ satisfaction. Conclusions: The results of the study showed that mother–infant attachment improved by increasing mothers’ satisfaction of supportive nursing care. Therefore, it seems necessary to increase maternal satisfaction through given nursing care support, in order to promote mother–infant attachment. PMID:26985225
Relationship between parent-infant attachment and parental satisfaction with supportive nursing care.

PubMed

Ghadery-Sefat, Akram; Abdeyazdan, Zahra; Badiee, Zohreh; Zargham-Boroujeni, Ali

2016-01-01

Parent-infant attachment is an important factor in accepting parenting role, accelerating infant survival, and adjusting to the environment outside the uterus. Since family supportive interventions can strengthen the parent-infant caring relationship, this study sought to investigate the relationship between mother-infant attachment and satisfaction of the mothers with the supportive nursing care received in the neonatal intensive care unit (NICU). In this descriptive-correlational study, 210 mothers with premature infants who were hospitalized in the NICUs affiliated to Isfahan Medical University hospitals took part. The data were collected via Maternal Postnatal Attachment Scale and researcher's self-tailored questionnaire based on Nurse Parent Support Tool. Pearson correlation coefficient and multiple linear regressions were used to analyze the collected data. The results showed that the overall score of mother-infant attachment and the overall score of maternal satisfaction correlated with a correlation coefficient of r = 0.195. Also, the overall score of mother-infant attachment and mothers' satisfaction scores in the emotional, communicative-informative, and self-confidence domains correlated with correlation coefficients of r = 0.182, r = 0.0.189, and r = 0.0.304, respectively. The results of multiple regression analysis revealed that about 15% of changes in the dependent variable (mother-infant attachment) could be explained by different dimensions of mothers' satisfaction. The results of the study showed that mother-infant attachment improved by increasing mothers' satisfaction of supportive nursing care. Therefore, it seems necessary to increase maternal satisfaction through given nursing care support, in order to promote mother-infant attachment.
Numerical Simulations of the Steady and Unsteady Aerodynamic Characteristics of a Circulation Control Wing Airfoil

NASA Technical Reports Server (NTRS)

Liu, Yi; Sankar, Lakshmi N.; Englar, Robert J.; Ahuja, Krishan K.

2003-01-01

The aerodynamic characteristics of a Circulation Control Wing (CCW) airfoil have been numerically investigated, and comparisons with experimental data have been made. The configuration chosen was a supercritical airfoil with a 30 degree dual-radius CCW flap. Steady and pulsed jet calculations were performed. It was found that the use of steady jets, even at very small mass flow rates, yielded a lift coefficient that is comparable or superior to conventional high-lift systems. The attached flow over the flap also gave rise to lower drag coefficients, and high L/D ratios. Pulsed jets with a 50% duty cycle were also studied. It was found that they were effective in generating lift at lower reduced mass flow rates compared to a steady jet, provided the pulse frequency was sufficiently high. This benefit was attributable to the fact that the momentum coefficient of the pulsed jet, during the portions of the cycle when the jet was on, was typically twice as much as that of a steady jet.
Aerodynamic analysis of formula student car

NASA Astrophysics Data System (ADS)

Dharmawan, Mohammad Arief; Ubaidillah, Nugraha, Arga Ahmadi; Wijayanta, Agung Tri; Naufal, Brian Aqif

2018-02-01

Formula Society of Automotive Engineering (FSAE) is a contest between ungraduated students to create a high-performance formula student car that completes the regulation. Body and the other aerodynamic devices are significant because it affects the drag coefficient and the down force of the car. The drag coefficient is a measurement of the resistance of an object in a fluid environment, a lower the drag coefficient means it will have a less drag force. Down force is a force that pushes an object to the ground, in the car more down force means more grip. The objective of the research was to study the aerodynamic comparison between the race vehicle when attached to the wings and without it. These studies were done in three dimensional (3D) computational fluid dynamic (CFD) simulation method using the Autodesk Flow Design software. These simulations were done by conducted in 5 different velocities. The results of those simulations are by attaching wings on race vehicle has drag coefficient 0.728 and without wings has drag coefficient 0.56. Wings attachment will decrease the drag coefficient about 23 % and also the contour pressure and velocity were known at these simulations.
On the relation between the activation energy for electron attachment reactions and the size of their thermal rate coefficients.

PubMed

Hotop, H; Ruf, M-W; Kopyra, J; Miller, T M; Fabrikant, I I

2011-02-14

Rate coefficients k(T) for dissociative electron attachment (DEA) to molecules in many cases exhibit a more or less strong rise with increasing temperature T (the electron temperature T(e) and the molecular temperature T(G) are assumed to be in thermal equilibrium, i.e., T = T(e) = T(G)). This rise is frequently modeled by the Arrhenius equation k(T) = k(A) exp[-E(a)∕(k(B)T)], and an activation energy E(a) is deduced from fits to the experimental data k(T). This behavior reflects the presence of an energy barrier for the anion on its path to the dissociated products. In a recent paper [J. Kopyra, J. Wnorowska, M. Foryś, and I. Szamrej, Int. J. Mass Spectrom. 268, 60 (2007)] it was suggested that the size of the rate coefficients for DEA reactions at room temperature exhibits an exponential dependence on the activation energy, i.e., k(E(a); T ≈ 300 K) = k(1) exp[-E(a)∕E(0)]. More recent experimental data for molecules with high barriers [T. M. Miller, J. F. Friedman, L. C. Schaffer, and A. A. Viggiano, J. Chem. Phys. 131, 084302 (2009)] are compatible with such a correlation. We investigate the validity and the possible origin of this dependence by analyzing the results of R-matrix calculations for temperature-dependent rate coefficients of exothermic DEA processes with intermediate barrier toward dissociation. These include results for model systems with systematically varied barrier height as well as results of molecule-specific calculations for CH(3)Cl, CH(3)Br, CF(3)Cl, and CH(2)Cl(2) (activation energies above 0.2 eV) involving appropriate molecular parameters. A comparison of the experimental and theoretical results for the considered class of molecules (halogenated alkanes) supports the idea that the exponential dependence of k(T = 300 K) on the activation energy reflects a general phenomenon associated with Franck-Condon factors for getting from the initial neutral vibrational levels to the dissociating final anion state in a direct DEA process. Cases are discussed for which the proposed relation does not apply.
Mitigation of radon and thoron decay products by filtration.

PubMed

Wang, Jin; Meisenberg, Oliver; Chen, Yongheng; Karg, Erwin; Tschiersch, Jochen

2011-09-01

Inhalation of indoor radon ((222)Rn) and thoron ((220)Rn) decay products is the most important source of exposure to ionizing radiation for the human respiratory tract. Decreasing ventilation rates due to energy saving reasons in new buildings suggest additional active mitigation techniques to reduce the exposure in homes with high radon and thoron concentrations but poor ventilation. Filtration techniques with HEPA filters and simple surgical mask material have been tested for their potential to reduce the indoor exposure in terms of the total effective dose for mixed radon and thoron indoor atmospheres. The tests were performed inside an experimental room providing stable conditions. Filtration (at filtration rates of 0.2 h(-1) and larger) removes attached radon and thoron decay products effectively but indoor aerosol as well. Therefore the concentration of unattached decay products (which have a higher dose coefficient) may increase. The decrease of the attached decay product concentrations could be theoretically described by a slowly decreasing exponential process. For attached radon decay products, it exhibited a faster but weaker removal process compared to attached thoron decay products (-70% for attached radon decay products and -80% for attached thoron decay products at a filtration rate of 0.5 h(-1) with an HEPA filter). The concentration of unattached thoron decay products increased distinctly during the filtration process (+300%) while that of unattached radon decay products rose only slightly though at a much higher level (+17%). In the theoretical description these observed differences could be attributed to the different half-lives of the nuclides. Considering both effects, reduced attached and increased unattached decay product concentrations, filtration could significantly decrease the total effective dose from thoron whereas the overall effect on radon dose is small. A permanent filtration is recommended because of the slow decrease of the thoron decay product concentrations. Copyright © 2011 Elsevier B.V. All rights reserved.
The effect of recombination and attachment on meteor radar diffusion coefficient profiles

NASA Astrophysics Data System (ADS)

Lee, C. S.; Younger, J. P.; Reid, I. M.; Kim, Y. H.; Kim, J.-H.

2013-04-01

Estimates of the ambipolar diffusion coefficient producedusing meteor radar echo decay times display an increasing trend below 80-85 km, which is inconsistent with a diffusion-only theory of the evolution of meteor trails. Data from the 33 MHz meteor radar at King Sejong Station, Antarctica, have been compared with observations from the Aura Earth Observing System Microwave Limb Sounder satellite instrument. It has been found that the height at which the diffusion coefficient gradient reverses follows the height of a constant neutral atmospheric density surface. Numerical simulations of meteor trail diffusion including dissociative recombination with atmospheric ions and three-body attachment of free electrons to neutral molecules indicate that three-body attachment is responsible for the distortion of meteor radar diffusion coefficient profiles at heights below 90 km, including the gradient reversal below 80-85 km. Further investigation has revealed that meteor trails with low initial electron line density produce decay times more consistent with a diffusion-only model of meteor trail evolution.
Catalysis-Enhancement via Rotary Fluctuation of F1-ATPase

PubMed Central

Watanabe, Rikiya; Hayashi, Kumiko; Ueno, Hiroshi; Noji, Hiroyuki

2013-01-01

Protein conformational fluctuations modulate the catalytic powers of enzymes. The frequency of conformational fluctuations may modulate the catalytic rate at individual reaction steps. In this study, we modulated the rotary fluctuation frequency of F1-ATPase (F1) by attaching probes with different viscous drag coefficients at the rotary shaft of F1. Individual rotation pauses of F1 between rotary steps correspond to the waiting state of a certain elementary reaction step of ATP hydrolysis. This allows us to investigate the impact of the frequency modulation of the rotary fluctuation on the rate of the individual reaction steps by measuring the duration of rotation pauses. Although phosphate release was significantly decelerated, the ATP-binding and hydrolysis steps were less sensitive or insensitive to the viscous drag coefficient of the probe. Brownian dynamics simulation based on a model similar to the Sumi-Marcus theory reproduced the experimental results, providing a theoretical framework for the role of rotational fluctuation in F1 rate enhancement. PMID:24268150
The application of dual-electrode through vial impedance spectroscopy for the determination of ice interface temperatures, primary drying rate and vial heat transfer coefficient in lyophilization process development.

PubMed

Smith, Geoff; Jeeraruangrattana, Yowwares; Ermolina, Irina

2018-06-22

Through vial impedance spectroscopy (TVIS) is a product non-invasive process analytical technology which exploits the frequency dependence of the complex impedance spectrum of a composite object (i.e. the freeze-drying vial and its contents) in order to track the progression of the freeze-drying cycle. This work demonstrates the use of a dual electrode system, attached to the external surface of a type I glass tubing vial (nominal capacity 10 mL) in the prediction of (i) the ice interface temperatures at the sublimation front and at the base of the vial, and (ii) the primary drying rate. A value for the heat transfer coefficient (for a chamber pressure of 270 µbar) was then calculated from these parameters and shown to be comparable to that published by Tchessalov[1]. Copyright © 2018. Published by Elsevier B.V.
Contrast between the mechanisms for dissociative electron attachment to CH3SCN and CH3NCS.

PubMed

Miller, Thomas M; Viggiano, Albert A; Shuman, Nicholas S

2018-05-14

The kinetics of thermal electron attachment to methyl thiocyanate (CH 3 SCN), methyl isothiocyanate (CH 3 NCS), and ethyl thiocyanate (C 2 H 5 SCN) were measured using flowing afterglow-Langmuir probe apparatuses at temperatures between 300 and 1000 K. CH 3 SCN and C 2 H 5 SCN undergo inefficient dissociative attachment to yield primarily SCN - at 300 K (k = 2 × 10 -10 cm 3 s -1 ), with increasing efficiency as temperature increases. The increase is well described by activation energies of 0.17 eV (CH 3 SCN) and 0.14 eV (C 2 H 5 SCN). CN - product is formed at <1% branching at 300 K, increasing to ∼30% branching at 1000 K. Attachment to CH 3 NCS yields exclusively SCN - ionic product but at a rate at 300 K that is below our detection threshold (k < 10 -12 cm 3 s -1 ). The rate coefficient increases rapidly with increasing temperature (k = 6 × 10 -11 cm 3 s -1 at 600 K), in a manner well described by an activation energy of 0.51 eV. Calculations at the B3LYP/def2-TZVPPD level suggest that attachment to CH 3 SCN proceeds through a dissociative state of CH 3 SCN - , while attachment to CH 3 NCS initially forms a weakly bound transient anion CH 3 NCS -* that isomerizes over an energetic barrier to yield SCN - . Kinetic modeling of the two systems is performed in an attempt to identify a kinetic signature differentiating the two mechanisms. The kinetic modeling reproduces the CH 3 NCS data only if dissociation through the transient anion is considered.
Contrast between the mechanisms for dissociative electron attachment to CH3SCN and CH3NCS

NASA Astrophysics Data System (ADS)

Miller, Thomas M.; Viggiano, Albert A.; Shuman, Nicholas S.

2018-05-01

The kinetics of thermal electron attachment to methyl thiocyanate (CH3SCN), methyl isothiocyanate (CH3NCS), and ethyl thiocyanate (C2H5SCN) were measured using flowing afterglow-Langmuir probe apparatuses at temperatures between 300 and 1000 K. CH3SCN and C2H5SCN undergo inefficient dissociative attachment to yield primarily SCN- at 300 K (k = 2 × 10-10 cm3 s-1), with increasing efficiency as temperature increases. The increase is well described by activation energies of 0.17 eV (CH3SCN) and 0.14 eV (C2H5SCN). CN- product is formed at <1% branching at 300 K, increasing to ˜30% branching at 1000 K. Attachment to CH3NCS yields exclusively SCN- ionic product but at a rate at 300 K that is below our detection threshold (k < 10-12 cm3 s-1). The rate coefficient increases rapidly with increasing temperature (k = 6 × 10-11 cm3 s-1 at 600 K), in a manner well described by an activation energy of 0.51 eV. Calculations at the B3LYP/def2-TZVPPD level suggest that attachment to CH3SCN proceeds through a dissociative state of CH3SCN-, while attachment to CH3NCS initially forms a weakly bound transient anion CH3NCS-* that isomerizes over an energetic barrier to yield SCN-. Kinetic modeling of the two systems is performed in an attempt to identify a kinetic signature differentiating the two mechanisms. The kinetic modeling reproduces the CH3NCS data only if dissociation through the transient anion is considered.
Transport Behavior of Functionalized Multi-Wall Carbon Nanotubes in Water-Saturated Quartz Sand as a Function of Tube Length

PubMed Central

Wang, Yonggang; Kim, Jae-Hong; Baek, Jong-Beom; Miller, Gary W.; Pennell, Kurt D.

2012-01-01

A series of one-dimensional column experiments was conducted to examine the effects of tube length on the transport and deposition of 4-ethoxybenzoic acid functionalized multi-wall carbon nanotubes (MWCNTs) in water-saturated porous media. Aqueous MWCNTs suspensions were prepared to yield three distributions of tube lengths; 0.02–1.3 μm (short), 0.2–7.5 μm (medium), and 0.2–21.4 μm (long). Results of the column studies showed that MWCNT retention increased with increasing tube length. Nevertheless, more than 76% of the MWCNT mass delivered to the columns was detected in effluent samples under all experimental conditions, indicating that the functionalized MWCNTs were readily transported through 40–50 mesh Ottawa sand. Examination of MWCNT length distributions in the effluent samples revealed that nanotubes with lengths greater than 8 μm were preferentially deposited. In addition, measured retention profiles exhibited the greatest MWCNT deposition near the column inlet, which was most pronounced for the long MWCNTs, and decreased sharply with travel distance. Scanning electron microscope (SEM) images showed that MWCNTs were deposited on sand surfaces over the entire column length, while larger MWCNT bundles were retained at grain intersections and near the column inlet. A mathematical model based on clean bed filtration theory (CBFT) was unable to accurately simulate the measured retention profile data, even after varying the weighting function and incorporating a nonuniform attachment rate coefficient expression. Modification of the mathematical model to account for physical straining greatly improved predictions of MWCNT retention, yielding straining rate coefficients that were four orders-of-magnitude greater than corresponding attachment rate coefficients. Taken in concert, these experimental and modeling results demonstrate the potential importance of, and need to consider, particle straining and tube length distribution when describing MWCNT transport in water-saturated porous media. PMID:22704927
Transport behavior of functionalized multi-wall carbon nanotubes in water-saturated quartz sand as a function of tube length.

PubMed

Wang, Yonggang; Kim, Jae-Hong; Baek, Jong-Beom; Miller, Gary W; Pennell, Kurt D

2012-09-15

A series of one-dimensional column experiments was conducted to examine the effects of tube length on the transport and deposition of 4-ethoxybenzoic acid functionalized multi-wall carbon nanotubes (MWCNTs) in water-saturated porous media. Aqueous MWCNTs suspensions were prepared to yield three distributions of tube lengths; 0.02-1.3 μm (short), 0.2-7.5 μm (medium), and 0.2-21.4 μm (long). Results of the column studies showed that MWCNT retention increased with increasing tube length. Nevertheless, more than 76% of the MWCNT mass delivered to the columns was detected in effluent samples under all experimental conditions, indicating that the functionalized MWCNTs were readily transported through 40-50 mesh Ottawa sand. Examination of MWCNT length distributions in the effluent samples revealed that nanotubes with lengths greater than 8 μm were preferentially deposited. In addition, measured retention profiles exhibited the greatest MWCNT deposition near the column inlet, which was most pronounced for the long MWCNTs, and decreased sharply with travel distance. Scanning electron microscope (SEM) images showed that MWCNTs were deposited on sand surfaces over the entire column length, while larger MWCNT bundles were retained at grain intersections and near the column inlet. A mathematical model based on clean bed filtration theory (CBFT) was unable to accurately simulate the measured retention profile data, even after varying the weighting function and incorporating a nonuniform attachment rate coefficient expression. Modification of the mathematical model to account for physical straining greatly improved predictions of MWCNT retention, yielding straining rate coefficients that were four orders-of-magnitude greater than corresponding attachment rate coefficients. Taken in concert, these experimental and modeling results demonstrate the potential importance of, and need to consider, particle straining and tube length distribution when describing MWCNT transport in water-saturated porous media. Copyright © 2012 Elsevier Ltd. All rights reserved.
Extracting rate coefficients from single-molecule photon trajectories and FRET efficiency histograms for a fast-folding protein.

PubMed

Chung, Hoi Sung; Gopich, Irina V; McHale, Kevin; Cellmer, Troy; Louis, John M; Eaton, William A

2011-04-28

Recently developed statistical methods by Gopich and Szabo were used to extract folding and unfolding rate coefficients from single-molecule Förster resonance energy transfer (FRET) data for proteins with kinetics too fast to measure waiting time distributions. Two types of experiments and two different analyses were performed. In one experiment bursts of photons were collected from donor and acceptor fluorophores attached to a 73-residue protein, α(3)D, freely diffusing through the illuminated volume of a confocal microscope system. In the second, the protein was immobilized by linkage to a surface, and photons were collected until one of the fluorophores bleached. Folding and unfolding rate coefficients and mean FRET efficiencies for the folded and unfolded subpopulations were obtained from a photon by photon analysis of the trajectories using a maximum likelihood method. The ability of the method to describe the data in terms of a two-state model was checked by recoloring the photon trajectories with the extracted parameters and comparing the calculated FRET efficiency histograms with the measured histograms. The sum of the rate coefficients for the two-state model agreed to within 30% with the relaxation rate obtained from the decay of the donor-acceptor cross-correlation function, confirming the high accuracy of the method. Interestingly, apparently reliable rate coefficients could be extracted using the maximum likelihood method, even at low (<10%) population of the minor component where the cross-correlation function was too noisy to obtain any useful information. The rate coefficients and mean FRET efficiencies were also obtained in an approximate procedure by simply fitting the FRET efficiency histograms, calculated by binning the donor and acceptor photons, with a sum of three-Gaussian functions. The kinetics are exposed in these histograms by the growth of a FRET efficiency peak at values intermediate between the folded and unfolded peaks as the bin size increases, a phenomenon with similarities to NMR exchange broadening. When comparable populations of folded and unfolded molecules are present, this method yields rate coefficients in very good agreement with those obtained with the maximum likelihood method. As a first step toward characterizing transition paths, the Viterbi algorithm was used to locate the most probable transition points in the photon trajectories.

Applicability of the Fokker-Planck equation to the description of diffusion effects on nucleation

NASA Astrophysics Data System (ADS)

Sorokin, M. V.; Dubinko, V. I.; Borodin, V. A.

2017-01-01

The nucleation of islands in a supersaturated solution of surface adatoms is considered taking into account the possibility of diffusion profile formation in the island vicinity. It is shown that the treatment of diffusion-controlled cluster growth in terms of the Fokker-Planck equation is justified only provided certain restrictions are satisfied. First of all, the standard requirement that diffusion profiles of adatoms quickly adjust themselves to the actual island sizes (adiabatic principle) can be realized only for sufficiently high island concentration. The adiabatic principle is essential for the probabilities of adatom attachment to and detachment from island edges to be independent of the adatom diffusion profile establishment kinetics, justifying the island nucleation treatment as the Markovian stochastic process. Second, it is shown that the commonly used definition of the "diffusion" coefficient in the Fokker-Planck equation in terms of adatom attachment and detachment rates is justified only provided the attachment and detachment are statistically independent, which is generally not the case for the diffusion-limited growth of islands. We suggest a particular way to define the attachment and detachment rates that allows us to satisfy this requirement as well. When applied to the problem of surface island nucleation, our treatment predicts the steady-state nucleation barrier, which coincides with the conventional thermodynamic expression, even though no thermodynamic equilibrium is assumed and the adatom diffusion is treated explicitly. The effect of adatom diffusional profiles on the nucleation rate preexponential factor is also discussed. Monte Carlo simulation is employed to analyze the applicability domain of the Fokker-Planck equation and the diffusion effect beyond it. It is demonstrated that a diffusional cloud is slowing down the nucleation process for a given monomer interaction with the nucleus edge.
Composite fastener for use in high temperature environments

NASA Technical Reports Server (NTRS)

Miller, Robert J. (Inventor); Palusis, Mark E. (Inventor); Jarmon, David C. (Inventor)

2000-01-01

A fastener includes a composite body and a metal coupling attached to the body. The metal coupling includes an attachment structure to connect the fastener to an external structure. An assembly of components includes a first metallic component having a first coefficient of thermal expansion, a second non-metallic component having a second coefficient of thermal expansion different from the first thermal expansion and having a groove that receives a fastener that extends between the groove and the second component, the fastener slidably engaging the groove to accommodate relative expansion between the components.
Determination of the external mass transfer coefficient and influence of mixing intensity in moving bed biofilm reactors for wastewater treatment.

PubMed

Nogueira, Bruno L; Pérez, Julio; van Loosdrecht, Mark C M; Secchi, Argimiro R; Dezotti, Márcia; Biscaia, Evaristo C

2015-09-01

In moving bed biofilm reactors (MBBR), the removal of pollutants from wastewater is due to the substrate consumption by bacteria attached on suspended carriers. As a biofilm process, the substrates are transported from the bulk phase to the biofilm passing through a mass transfer resistance layer. This study proposes a methodology to determine the external mass transfer coefficient and identify the influence of the mixing intensity on the conversion process in-situ in MBBR systems. The method allows the determination of the external mass transfer coefficient in the reactor, which is a major advantage when compared to the previous methods that require mimicking hydrodynamics of the reactor in a flow chamber or in a separate vessel. The proposed methodology was evaluated in an aerobic lab-scale system operating with COD removal and nitrification. The impact of the mixing intensity on the conversion rates for ammonium and COD was tested individually. When comparing the effect of mixing intensity on the removal rates of COD and ammonium, a higher apparent external mass transfer resistance was found for ammonium. For the used aeration intensities, the external mass transfer coefficient for ammonium oxidation was ranging from 0.68 to 13.50 m d(-1) and for COD removal 2.9 to 22.4 m d(-1). The lower coefficient range for ammonium oxidation is likely related to the location of nitrifiers deeper in the biofilm. The measurement of external mass transfer rates in MBBR will help in better design and evaluation of MBBR system-based technologies. Copyright © 2015 Elsevier Ltd. All rights reserved.
Non-monotonic permeability variation during colloidal transport: Governing equations and analytical model

NASA Astrophysics Data System (ADS)

Chequer, L.; Russell, T.; Behr, A.; Genolet, L.; Kowollik, P.; Badalyan, A.; Zeinijahromi, A.; Bedrikovetsky, P.

2018-02-01

Permeability decline associated with the migration of natural reservoir fines impairs the well index of injection and production wells in aquifers and oilfields. In this study, we perform laboratory corefloods using aqueous solutions with different salinities in engineered rocks with different kaolinite content, yielding fines migration and permeability alteration. Unusual permeability growth has been observed at high salinities in rocks with low kaolinite concentrations. This has been attributed to permeability increase during particle detachment and re-attachment of already mobilised fines by electrostatic attraction to the rock in stagnant zones of the porous space. We refine the traditional model for fines migration by adding mathematical expressions for the particle re-attachment rate, particle detachment with delay relative to salinity decrease, and the attached-concentration-dependency of permeability. A one-dimensional flow problem that accounts for those three effects allows for an exact analytical solution. The modified model captures the observed effect of permeability increase at high water salinities in rocks with low kaolinite concentrations. The developed model matches the coreflooding data with high accuracy, and the obtained model coefficients vary within their usual intervals.
Features and heterogeneities in growing network models

NASA Astrophysics Data System (ADS)

Ferretti, Luca; Cortelezzi, Michele; Yang, Bin; Marmorini, Giacomo; Bianconi, Ginestra

2012-06-01

Many complex networks from the World Wide Web to biological networks grow taking into account the heterogeneous features of the nodes. The feature of a node might be a discrete quantity such as a classification of a URL document such as personal page, thematic website, news, blog, search engine, social network, etc., or the classification of a gene in a functional module. Moreover the feature of a node can be a continuous variable such as the position of a node in the embedding space. In order to account for these properties, in this paper we provide a generalization of growing network models with preferential attachment that includes the effect of heterogeneous features of the nodes. The main effect of heterogeneity is the emergence of an “effective fitness” for each class of nodes, determining the rate at which nodes acquire new links. The degree distribution exhibits a multiscaling behavior analogous to the the fitness model. This property is robust with respect to variations in the model, as long as links are assigned through effective preferential attachment. Beyond the degree distribution, in this paper we give a full characterization of the other relevant properties of the model. We evaluate the clustering coefficient and show that it disappears for large network size, a property shared with the Barabási-Albert model. Negative degree correlations are also present in this class of models, along with nontrivial mixing patterns among features. We therefore conclude that both small clustering coefficients and disassortative mixing are outcomes of the preferential attachment mechanism in general growing networks.
Filament wound data base development, revision 1, appendix A

NASA Technical Reports Server (NTRS)

Sharp, R. Scott; Braddock, William F.

1985-01-01

Data are presented in tabular form for the High Performance Nozzle Increments, Filament Wound Case (FWC) Systems Tunnel Increments, Steel Case Systems Tunnel Increments, FWC Stiffener Rings Increments, Steel Case Stiffener Rings Increments, FWC External Tank (ET) Attach Ring Increments, Steel Case ET Attach Ring Increments, and Data Tape 8. The High Performance Nozzle are also presented in graphical form. The tabular data consist of six-component force and moment coefficients as they vary with angle of attack at a specific Mach number and roll angle. The six coefficients are normal force, pitching moment, side force, yawing moment, axial force, and rolling moment. The graphical data for the High Performance Nozzle Increments consist of a plot of a coefficient increment as a function of angle of attack at a specific Mach number and at a roll angle of 0 deg.
Reduction of friction stress of ethylene glycol by attached hydrogen ions

PubMed Central

Li, Jinjin; Zhang, Chenhui; Deng, Mingming; Luo, Jianbin

2014-01-01

In the present work, it is shown that the friction stress of ethylene glycol can decrease by an order of magnitude to achieve superlubricity if there are hydrogen ions attached on the friction surfaces. An ultra-low friction coefficient (μ = 0.004) of ethylene glycol between Si3N4 and SiO2 can be obtained with the effect of hydrogen ions. Experimental result indicates that the hydrogen ions adsorbed on the friction surfaces forming a hydration layer and the ethylene glycol in the contact region forming an elastohydrodynamic film are the two indispensable factors for the reduction of friction stress. The mechanism of superlubricity is attributed to the extremely low shear strength of formation of elastohydrodynamic film on the hydration layer. This finding may introduce a new approach to reduce friction coefficient of liquid by attaching hydrogen ions on friction surfaces. PMID:25428584
Testing For Measurement Invariance of Attachment Across Chinese and American Adolescent Samples.

PubMed

Ren, Ling; Zhao, Jihong Solomon; He, Ni Phil; Marshall, Ineke Haen; Zhang, Hongwei; Zhao, Ruohui; Jin, Cheng

2016-06-01

Adolescent attachment to formal and informal institutions has emerged as a major focus of criminological theories since the publication of Hirschi's work in 1969. This study attempts to examine the psychometric equivalence of the factorial structure of attachment measures across nations reflecting Western and Eastern cultures. Twelve manifest variables are used tapping the concepts of adolescent attachment to parents, school, and neighborhood. Confirmatory factor analysis is used to conduct invariance test across approximately 3,000 Chinese and U.S. adolescents. Results provide strong support for a three-factor model; the multigroup invariance tests reveal mixed results. While the family attachment measure appears invariant between the two samples, significant differences in the coefficients of the factor loadings are detected in the school attachment and neighborhood attachment measures. The results of regression analyses lend support to the predictive validity of three types of attachment. Finally, the limitations of the study are discussed. © The Author(s) 2015.
Determination of pollutant diffusion coefficients in naturally formed biofilms using a single tube extractive membrane bioreactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, S.F.; Splendiani, A.; Freitas dos Santos, L.M.

A novel technique has been used to determine the effective diffusion coefficients for 1,1,2-trichloroethane (TCE), a nonreacting tracer, in biofilms growing on the external surface of a silicone rubber membrane tube during degradation of 1,2-dichloroethane (DCE) by Xanthobacter autotrophicus GJ10 and monochlorobenzene (MCB) by Pseudomonas JS150. Experiments were carried out in a single tube extractive membrane bioreactor (STEMB), whose configuration makes it possible to measure the transmembrane flux of substrates. A video imaging technique (VIT) was employed for in situ biofilm thickness measurement and recording. Diffusion coefficients of TCE in the biofilms and TCE mass transfer coefficients in the liquidmore » films adjacent to the biofilms were determined simultaneously using a resistances-in-series diffusion model. It was found that the flux and overall mass transfer coefficient of TCE decrease with increasing biofilm thickness, showing the importance of biofilm diffusion on the mass transfer process. Similar fluxes were observed for the nonreacting tracer (TCE) and the reactive substrates (MCB or DCE), suggesting that membrane-attached biofilm systems can be rate controlled primarily by substrate diffusion. The TCE diffusion coefficient in the JS150 biofilm appeared to be dependent on biofilm thickness, decreasing markedly for biofilm thicknesses of >1 mm. The values of the TCE diffusion coefficients in the JS150 biofilms <1-mm thick are approximately twice those in water and fall to around 30% of the water value for biofilms >1-mm thick.« less
Modeling Engineered Nanomaterials (ENMs) Fate and ...

EPA Pesticide Factsheets

Under the Toxic Substances Control Act (TSCA), the Environmental Protection Agency (EPA) is required to perform new chemical reviews of engineered nanomaterials (ENMs) identified in pre-manufacture notices. However, environmental fate models developed for traditional contaminants are limited in their ability to simulate the environmental behavior of nanomaterials due to incomplete understanding and representation of the processes governing nanomaterial distribution in the environment and by scarce empirical data quantifying the interaction of nanomaterials with environmental surfaces. We have updated the Water Quality Analysis Simulation Program (WASP), version S, to incorporate nanomaterials as an explicitly simulated state variable. WASPS now has the capability to simulate nanomaterial fate and transport in surface waters and sediments using heteroaggregation, the kinetic process governing the attachment of nanomaterials to particles and subsequently ENM distribution in the aqueous and sediment phases. Unlike dissolved chemicals which use equilibrium partition coefficients, heteroaggregation consists of a particle collision rate and an attachment efficiency ( lXhet) that generally acts as a one direction process. To demonstrate, we used a derived a het value from sediment attachment studies to parameterize WASP for simulation of multi walled carbon nanotube (MWCNT) transport in Brier Creek, a coastal plain river located in central eastern Georgia, USA and a tr
Modeling removal of bacteriophages MS2 and PRD1 by dune recharge at Castricum, Netherlands

NASA Astrophysics Data System (ADS)

Schijven, Jack F.; Hoogenboezem, Wim; Hassanizadeh, S. Majid; Peters, Jos H.

1999-04-01

Removal of model viruses by dune recharge was studied at a field site in the dune area of Castricum, Netherlands. Recharge water was dosed with bacteriophages MS2 and PRD1 for 11 days at a constant concentration in a 10- by 15-m compartment that was isolated in a recharge basin. Breakthrough was monitored for 120 days at six wells with their screens along a flow line. Concentrations of both phages were reduced about 3 log10 within the first 2.4 m and another 5 log10 in a linear fashion within the following 27 m. A model accounting for one-site kinetic attachment as well as first-order inactivation was employed to simulate the bacteriophage breakthrough curves. The major removal process was found to be attachment of the bacteriophages. Detachment was very slow. After passage of the pulse of dosed bacteriophages, there was a long tail whose slope corresponds to the inactivation rate coefficient of 0.07-0.09 day-1 for attached bacteriophages. The end of the rising and the start of the declining limbs of the breakthrough curves could not be simulated completely, probably because of an as yet unknown process.
Dissociative recombination and mutual neutralization of heavier molecular ions: C{sub 10}H{sub 8}{sup +}, WF{sub 5}{sup +}, and C{sub n}F{sub m}{sup +}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiens, Justin P.; Shuman, Nicholas S.; Viggiano, Albert A., E-mail: afrl.rvborgmailbox@kirtland.af.mil

Dissociative recombination (DR) rate coefficients for the naphthalene cation, C{sub 10}H{sub 8}{sup +}, and WF{sub 5}{sup +}, and mutual neutralization (MN) rate coefficients for these species and five C{sub n}F{sub m}{sup +} ions, were determined at 300 K using variable electron and neutral density attachment mass spectrometry (VENDAMS). DR proceeds at 9 ± 3 × 10{sup −7} cm{sup 3} s{sup −1} for C{sub 10}H{sub 8}{sup +} and at 6.1 ± 1.4 × 10{sup −7} cm{sup 3} s{sup −1} for WF{sub 5}{sup +}. Consistent with previous results, MN for the polyatomic cations with the halide anions Cl{sup −}, Br{sup −}, andmore » I{sup −} exhibits an approximate μ{sup −1/2} reduced mass dependence of the reactant partners, demonstrating that ion collision velocities influence the rate coefficients. This work is an extension of VENDAMS to systems, where low reactant concentrations are necessary to avoid significant reaction of product ions with the neutral precursor, i.e., conditions not suitable for traditional flowing afterglow measurements, as well as to ions of masses > ∼ 100 Da, which are not amenable to the study of DR in magnetic storage rings. Our results expand the sparse literature on DR and MN of heavier ions.« less
A Study Of High Speed Friction Behavior Under Elastic Loading Conditions

NASA Astrophysics Data System (ADS)

Crawford, P. J.; Hammerberg, J. E.

2005-03-01

The role of interfacial dynamics under high strain-rate conditions is an important constitutive relationship in modern modeling and simulation studies of dynamic events (<100 μs in length). The frictional behavior occurring at the interface between two metal surfaces under high elastic loading and sliding speed conditions is studied using the Rotating Barrel Gas Gun (RBGG) facility. The RBGG utilizes a low-pressure gas gun to propel a rotating annular projectile towards an annular target rod. Upon striking the target, the projectile imparts both an axial and a torsional impulse into the target. Resulting elastic waves are measured using strain gauges attached to the target rod. The kinetic coefficient of friction is obtained through an analysis of the resulting strain wave data. Experiments performed using Cu/Cu, Cu/Stainless steel and Cu/Al interfaces provide some insight into the kinetic coefficient of friction behavior at varying sliding speeds and impact loads.
Refined BCF-type boundary conditions for mesoscale surface step dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Renjie; Ackerman, David M.; Evans, James W.

Deposition on a vicinal surface with alternating rough and smooth steps is described by a solid-on-solid model with anisotropic interactions. Kinetic Monte Carlo (KMC) simulations of the model reveal step pairing in the absence of any additional step attachment barriers. We explore the description of this behavior within an analytic Burton-Cabrera-Frank (BCF)-type step dynamics treatment. Without attachment barriers, conventional kinetic coefficients for the rough and smooth steps are identical, as are the predicted step velocities for a vicinal surface with equal terrace widths. However, we determine refined kinetic coefficients from a two-dimensional discrete deposition-diffusion equation formalism which accounts for stepmore » structure. These coefficients are generally higher for rough steps than for smooth steps, reflecting a higher propensity for capture of diffusing terrace adatoms due to a higher kink density. Such refined coefficients also depend on the local environment of the step and can even become negative (corresponding to net detachment despite an excess adatom density) for a smooth step in close proximity to a rough step. Incorporation of these refined kinetic coefficients into a BCF-type step dynamics treatment recovers quantitatively the mesoscale step-pairing behavior observed in the KMC simulations.« less
Refined BCF-type boundary conditions for mesoscale surface step dynamics

DOE PAGES

Zhao, Renjie; Ackerman, David M.; Evans, James W.

2015-06-24

Deposition on a vicinal surface with alternating rough and smooth steps is described by a solid-on-solid model with anisotropic interactions. Kinetic Monte Carlo (KMC) simulations of the model reveal step pairing in the absence of any additional step attachment barriers. We explore the description of this behavior within an analytic Burton-Cabrera-Frank (BCF)-type step dynamics treatment. Without attachment barriers, conventional kinetic coefficients for the rough and smooth steps are identical, as are the predicted step velocities for a vicinal surface with equal terrace widths. However, we determine refined kinetic coefficients from a two-dimensional discrete deposition-diffusion equation formalism which accounts for stepmore » structure. These coefficients are generally higher for rough steps than for smooth steps, reflecting a higher propensity for capture of diffusing terrace adatoms due to a higher kink density. Such refined coefficients also depend on the local environment of the step and can even become negative (corresponding to net detachment despite an excess adatom density) for a smooth step in close proximity to a rough step. Incorporation of these refined kinetic coefficients into a BCF-type step dynamics treatment recovers quantitatively the mesoscale step-pairing behavior observed in the KMC simulations.« less
Detachment of solids and nitrifiers in integrated, fixed-film activated sludge systems.

PubMed

Maas, Carol L A; Parker, Wayne J; Legge, Raymond L

2008-12-01

Despite the importance of detachment to biofilm processes, detachment phenomena are not well understood. In this study, researchers investigated biofilm detachment from free-floating biofilm carriers that were established in an integrated, fixed-film activated sludge (IFAS) installation in Mississauga, Ontario. A method for assessing detachment from biofilm carrier systems was devised, evaluated, and refined during this study. In the absence of substrate, superficial air velocity significantly affected the 24-hour detachment rates of total suspended solids from the carriers. Short-term growth conditions did not appear to significantly affect the rate of detachment of solids and nitrifiers. The measured solids-detachment rates were found to be described by a second order function of biofilm attached growth total solids with a detachment coefficient of 0.006 +/- 0.0008 (g/m x d)(-1).
Study of supersonic wings employing the attainable leading-edge thrust concept

NASA Technical Reports Server (NTRS)

Middleton, W. D.

1982-01-01

A theoretical study was made of supersonic wing geometries at Mach 1.8, using the attainable leading-edge thrust concept. The attainable thrust method offers a powerful means to improve overall aerodynamic efficiency by identifying wing leading-edge geometries that promote attached flow and by defining a local angle-of-attack range over which attached flow may be obtained. The concept applies to flat and to cambered wings, which leads to the consideration of drooped-wing leading edges for attached flow at high lift coefficients.
Nanocomposite Interphases for Improved Transparent Polymer Composite Materials

DTIC Science & Technology

2008-08-01

intensity of the incident light, A is the attenuation coefficient , and t is the part thickness. The intensity attenuation coefficient is a function of...index that is fairly close to that of fused silica. Most importantly, it has a high thermo- optic coefficient , dn/dt, which results in a large change in...35765K164, McMaster -Carr, Robbinsville, NJ) were attached on the outer side of both aluminum plates as shown, and the temperature was controlled
Electron swarm properties under the influence of a very strong attachment in SF6 and CF3I obtained by Monte Carlo rescaling procedures

NASA Astrophysics Data System (ADS)

Mirić, J.; Bošnjaković, D.; Simonović, I.; Petrović, Z. Lj; Dujko, S.

2016-12-01

Electron attachment often imposes practical difficulties in Monte Carlo simulations, particularly under conditions of extensive losses of seed electrons. In this paper, we discuss two rescaling procedures for Monte Carlo simulations of electron transport in strongly attaching gases: (1) discrete rescaling, and (2) continuous rescaling. The two procedures are implemented in our Monte Carlo code with an aim of analyzing electron transport processes and attachment induced phenomena in sulfur-hexafluoride (SF6) and trifluoroiodomethane (CF3I). Though calculations have been performed over the entire range of reduced electric fields E/n 0 (where n 0 is the gas number density) where experimental data are available, the emphasis is placed on the analysis below critical (electric gas breakdown) fields and under conditions when transport properties are greatly affected by electron attachment. The present calculations of electron transport data for SF6 and CF3I at low E/n 0 take into account the full extent of the influence of electron attachment and spatially selective electron losses along the profile of electron swarm and attempts to produce data that may be used to model this range of conditions. The results of Monte Carlo simulations are compared to those predicted by the publicly available two term Boltzmann solver BOLSIG+. A multitude of kinetic phenomena in electron transport has been observed and discussed using physical arguments. In particular, we discuss two important phenomena: (1) the reduction of the mean energy with increasing E/n 0 for electrons in \\text{S}{{\\text{F}}6} and (2) the occurrence of negative differential conductivity (NDC) in the bulk drift velocity only for electrons in both \\text{S}{{\\text{F}}6} and CF3I. The electron energy distribution function, spatial variations of the rate coefficient for electron attachment and average energy as well as spatial profile of the swarm are calculated and used to understand these phenomena.
Instability and Transition of Flow at, and Near, an Attachment-Line: Including Control by Surface Suction

NASA Technical Reports Server (NTRS)

Smith, A.; Poll, D. I. A.

1998-01-01

Experiments have been performed on an untapered, swept cylinder model in the Cranfield College of Aeronautics 8 ft x 6 ft low-speed wind tunnel to investigate the effect of surface transpiration on the process of relaminarization in the attachment-line boundary layer. Suction coefficients for complete suppression of turbulence were determined as a function of Reynolds number and spanwise distance. The effect of attachment-line suction on the spanwise propagation of gross disturbances emanating from the fuselage-wing junction region was also studied. Finally, the effect of blowing on a laminar attachment-line boundary layer was also considered and excellent agreement was achieved with previous studies.

Attachment systems for mandibular implant overdentures: a systematic review

PubMed Central

Kim, Ha-Young; Lee, Jeong-Yol; Bryant, S. Ross

2012-01-01

PURPOSE The aim of this systematic review was to address treatment outcome according to attachment systems for mandibular implant overdentures in terms of implant survival rate, prosthetic maintenance and complications, and patient satisfaction. MATERIALS AND METHODS A systematic literature search was conducted using PubMed and hand searching of relevant journals considering inclusion and exclusion criteria. Clinical trial studies on mandibular implant overdentures until August, 2010 were selected if more than one type of overdenture attachment was reported. Twenty four studies from 1098 studies were finally included and the data on implant survival rate, prosthetic maintenance and complications, patient satisfaction were analyzed relative to attachment systems. RESULTS Four studies presented implant survival rates (95.8 - 97.5% for bar, 96.2 - 100% for ball, 91.7% for magnet) according to attachment system. Ten other studies presented an implant survival rate ranging from 93.3% to 100% without respect to the attachment groups. Common prosthetic maintenance and complications were replacement of an assay for magnet attachments, and activation of a matrix or clip for ball or bar attachments. Prosthetic maintenance and complications most commonly occurred in the magnet groups. Conflicting findings were found on the rate of prosthetic maintenance and complications comparing ball and bar attachments. Most studies showed no significant differences in patient satisfaction depending upon attachment systems. CONCLUSION The implant survival rate of mandibular overdentures seemed to be high regardless attachment systems. The prosthetic maintenance and complications may be influenced by attachment systems. However patient satisfaction may be independent of the attachment system. PMID:23236571
Zero Pearson coefficient for strongly correlated growing trees

NASA Astrophysics Data System (ADS)

Dorogovtsev, S. N.; Ferreira, A. L.; Goltsev, A. V.; Mendes, J. F. F.

2010-03-01

We obtained Pearson’s coefficient of strongly correlated recursive networks growing by preferential attachment of every new vertex by m edges. We found that the Pearson coefficient is exactly zero in the infinite network limit for the recursive trees (m=1) . If the number of connections of new vertices exceeds one (m>1) , then the Pearson coefficient in the infinite networks equals zero only when the degree distribution exponent γ does not exceed 4. We calculated the Pearson coefficient for finite networks and observed a slow power-law-like approach to an infinite network limit. Our findings indicate that Pearson’s coefficient strongly depends on size and details of networks, which makes this characteristic virtually useless for quantitative comparison of different networks.
Zero Pearson coefficient for strongly correlated growing trees.

PubMed

Dorogovtsev, S N; Ferreira, A L; Goltsev, A V; Mendes, J F F

2010-03-01

We obtained Pearson's coefficient of strongly correlated recursive networks growing by preferential attachment of every new vertex by m edges. We found that the Pearson coefficient is exactly zero in the infinite network limit for the recursive trees (m=1). If the number of connections of new vertices exceeds one (m>1), then the Pearson coefficient in the infinite networks equals zero only when the degree distribution exponent gamma does not exceed 4. We calculated the Pearson coefficient for finite networks and observed a slow power-law-like approach to an infinite network limit. Our findings indicate that Pearson's coefficient strongly depends on size and details of networks, which makes this characteristic virtually useless for quantitative comparison of different networks.
The role of alginate in Pseudomonas aeruginosa EPS adherence, viscoelastic properties and cell attachment.

PubMed

Orgad, Oded; Oren, Yoram; Walker, Sharon L; Herzberg, Moshe

2011-08-01

Among various functions, extracellular polymeric substances (EPS) provide microbial biofilms with mechanical stability and affect initial cell attachment, the first stage in the biofilm formation process. The role of alginate, an abundant polysaccharide in Pseudomonas aeruginosa biofilms, in the viscoelastic properties and adhesion kinetics of EPS was analyzed using a quartz crystal microbalance with dissipation (QCM-D) monitoring technology. EPS was extracted from two P. aeruginosa biofilms, a wild type strain, PAO1, and a mucoid strain, PAOmucA22 that over-expresses alginate production. The higher alginate content in the EPS originating from the mucoid biofilms was clearly shown to increase both the rate and the extent of attachment of the EPS, as well as the layer's thickness. Also, the presence of calcium and elevated ionic strength increased the thickness of the EPS layer. Dynamic light scattering (DLS) showed that the presence of calcium and elevated ionic strength induced intermolecular attractive interactions in the mucoid EPS molecules. For the wild type EPS, in the presence of calcium, an elevated shift in the distribution of the diffusion coefficients was observed with DLS due to a more compacted conformation of the EPS molecules. Moreover, the alginate over-expression effect on EPS adherence was compared to the effect of alginate over-expression on P. aeruginosa cell attachment. In a parallel plate flow cell, under similar hydraulic and aquatic conditions as those applied for the EPS adsorption tests in the QCM-D flow cell, reduced adherence of the mucoid strain was clearly observed compared to the wild type isogenic bacteria. The results suggest that alginate contributes to steric hindrance and shielding of cell surface features and adhesins that are known to promote cell attachment. © 2011 Taylor & Francis
Computational Fluid Dynamics (CFD) Simulation of Drag Reduction by Riblets on Automobile

NASA Astrophysics Data System (ADS)

Ghazali, N. N. N.; Yau, Y. H.; Badarudin, A.; Lim, Y. C.

2010-05-01

One of the ongoing automotive technological developments is the reduction of aerodynamic drag because this has a direct impact on fuel reduction, which is a major topic due to the influence on many other requirements. Passive drag reduction techniques stand as the most portable and feasible way to be implemented in real applications. One of the passive techniques is the longitudinal microgrooves aligned in the flow direction, known as riblets. In this study, the simulation of turbulent flows over an automobile in a virtual wind tunnel has been conducted by computational fluid dynamics (CFD). Three important aspects of this study are: the drag reduction effect of riblets on smooth surface automobile, the position and geometry of the riblets on drag reduction. The simulation involves three stages: geometry modeling, meshing, solving and analysis. The simulation results show that the attachment of riblets on the rear roof surface reduces the drag coefficient by 2.74%. By adjusting the attachment position of the riblets film, reduction rates between the range 0.5%-9.51% are obtained, in which the position of the top middle roof optimizes the effect. Four riblet geometries are investigated, among them the semi-hexagon trapezoidally shaped riblets is considered the most effective. Reduction rate of drag is found ranging from -3.34% to 6.36%.
High Prevalence of Insecure Attachment in Patients with Primary Hypertension

PubMed Central

Balint, Elisabeth M.; Gander, Manuela; Pokorny, Dan; Funk, Alexandra; Waller, Christiane; Buchheim, Anna

2016-01-01

Hypertension is a major cardiovascular (CV) risk factor and is predicted by heightened CV reactivity to stress in healthy individuals. Patients with hypertension also show an altered stress response, while insecure attachment is linked to a heightened stress reactivity as well. This is the first study aiming to assess attachment representations in patients with primary hypertension and to investigate their CV responses when their attachment system is activated. We studied 50 patients (38 men, 12 women) with primary hypertension. The Adult Attachment Projective Picture System (AAP), a widely used and validated interview, was performed to measure the patients' attachment representations, and to activate their attachment system. Blood pressure and heart rate were measured after 10 min at rest prior to and directly after the AAP interview. Mood and state anxiety were assessed using the Multidimensional Mood State Questionnaire (MDBF) and the State Trait Anxiety Inventory-State (STAI-S) before and after the experiment. The prevalence of insecure attachment (dismissing, preoccupied, unresolved) in hypertensive patients was predominant (88%), while in non-clinical populations, only about 50% of individuals had insecure attachment patterns. Blood pressure (p < 0.001), heart rate (p = 0.016), and rate pressure product (p < 0.001) significantly increased in response to the attachment interview. Secure attached patients showed the highest rise in systolic blood pressure (p = 0.020) and the lowest heart rate compared to the other attachment groups (p = 0.043). However, attachment representation showed no significant group or interaction effects on diastolic blood pressure (DBP) and rate pressure product. Insecure attachment was highly over-represented in our sample of patients with primary hypertension. Additionally, a robust CV response to the attachment-activating stimulus was observed. Our data suggest that insecure attachment is significantly linked to primary hypertension, which implies the need for further investigations to evaluate attachment insecurity as a possible risk factor for hypertension. PMID:27536255
Children's thoughts and feelings about their donor and security of attachment to their solo mothers in middle childhood.

PubMed

Zadeh, S; Jones, C M; Basi, T; Golombok, S

2017-04-01

What is the relationship between children's thoughts and feelings about their donor and their security of attachment to their solo mothers in middle childhood? Children with higher levels of secure-autonomous attachment to their mothers were more likely to have positive perceptions of the donor, and those with higher levels of insecure-disorganized attachment to their mothers were more likely to perceive him negatively. There is limited understanding of the factors that contribute to children's thoughts and feelings about their donor in solo mother families. In adolescence, an association was found between adolescents' curiosity about donor conception and their security of attachment to their mothers. 19 children were administered the Friends and Family Interview and Donor Conception Interview between December 2015 and March 2016 as part of the second phase of a longitudinal, multi-method, multi-informant study of solo mother families. All children were aged between 7 and 13 years and had been conceived by donor insemination to solo mothers. Interviews were conducted in participants' homes. The Friends and Family Interview was rated according to a standardized coding scheme designed to measure security of attachment in terms of secure-autonomous, insecure-dismissing, insecure-preoccupied and insecure-disorganized attachment patterns. Quantitative analyses of the Donor Conception Interview yielded two factors: interest in the donor and perceptions of the donor. Qualitative analyses of the Donor Conception Interview were conducted using qualitative content analysis and thematic analysis. Statistically significant associations were found between the perception of the donor scale and the secure-autonomous and insecure-disorganized attachment ratings. Children with higher levels of secure-autonomous attachment to their mothers were more likely to have positive perceptions of the donor (r = 0.549, P = 0.015), and those with higher levels of insecure-disorganized attachment to their mothers were more likely to perceive him negatively (r = -0.632, P = 0.004). Children's narratives about the donor depicted him as a stranger (n = 8), a biological father (n = 4), a social parent (n = 3), or in ambivalent terms (n = 4). Findings are limited by the wide age range of children within a small overall sample size. Participants were those willing and able to take part in research on donor conception families. The statistical significance of correlation coefficients was not corrected for multiple comparisons. Findings highlight the importance of situating children's ideas about the donor within family contexts. It is recommended that those working with donor conception families consider this when advising parents about whether, what and how to tell children about donor conception. This study was funded by the Wellcome Trust [097857/Z/11/Z]. The authors have no conflicts of interest to declare. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.
Relationships between maternal adult attachment security, child perceptions of maternal support, and maternal perceptions of child responses to sexual abuse.

PubMed

Leifer, Myra; Kilbane, Teresa; Skolnick, Linda

2002-01-01

This study assessed the relationships between maternal adult attachment style, children's perceptions of maternal support following disclosure of sexual abuse, and maternal perceptions of children's behavioral and emotional responses to sexual abuse among African-American child sexual abuse victims aged 4 to 12 (n=96) and a comparison group of non-abused subjects (n=100). Mothers with insecure attachment styles reported significantly higher rates of internalizing behaviors in their sexually abused children than did securely attached mothers. Among mothers of non-abused children, those with insecure adult attachment styles reported significantly higher rates of externalizing behaviors shown by their children in comparison with mothers with a secure adult attachment style. Mothers with insecure adult attachment styles also reported higher rates of overall behavior problems in their non-abused children that approached statistical significance. Sexually abused children's perceptions of maternal support were not related to maternal attachment style nor to child functioning. Contrary to our prediction, mothers of sexually abused children did not show lower rates of secure attachments when compared to mothers of non-sexually abused children. Our findings indicate that fostering parent- child attachment is important in order to decrease the risk for behavior problems and symptomatology in sexually abused children.
Is Early Attachment Security Carried Forward into Relationships with Preschool Peers?

ERIC Educational Resources Information Center

Wood, Jeffrey J.; Emmerson, Natasha A.; Cowan, Philip A.

2004-01-01

The association between early parent-child attachment security and peer rejection among preschool children was examined. Children in three preschool classrooms (N = 37) participated. Mothers rated their children's attachment security at age 3 years on the Attachment Q-Set (Waters, 1987). Sociometric ratings were collected from classmates at age 4…
The generation of side force by distributed suction

NASA Technical Reports Server (NTRS)

Roberts, Leonard; Hong, John

1993-01-01

This report provides an approximate analysis of the generation of side force on a cylinder placed horizontal to the flow direction by the application of distributed suction on the rearward side of the cylinder. Relationships are derived between the side force coefficients and the required suction coefficients necessary to maintain attached flow on one side of the cylinder, thereby inducing circulation around the cylinder and a corresponding side force.
Supersonic axial-force characteristics of a rectangular-box cavity with various length-to-depth ratios in a flat plate

NASA Technical Reports Server (NTRS)

Blair, A. B., Jr.; Stallings, R. L., Jr.

1986-01-01

A wind-tunnel investigation has been conducted at Mach numbers of 1.50, 2.16, and 2.86 to obtain axial-force data on a metric rectangular-box cavity with various length-to-depth ratios. The model was tested at angles of attack from -4 deg to -2 deg. The results are summarized to show variations in cavity axial-force coefficient for deep- and shallow-cavity configurations with detached and attached cavity flow fields, respectively. The results of the investigation indicate that for a wide range of cavity lengths and depths, good correlations of the cavity axial-force coefficients (based on cavity rear-face area) are obtained when these coefficients are plotted as a function of cavity length-to-depth ratio. Abrupt increases in the cavity axial-force coefficients at an angle of attack of 0 deg. reflect the transition from an open (detached) cavity flow field to a closed (attached) cavity flow field. Cavity length-to-depth ratio is the dominant factor affecting the switching of the cavity flow field from one type to the other. The type of cavity flow field (open or closed) is not dependent on the test angles of attack except near the critical value of length-to-depth ratio.
Escherichia coli attachment to model particulates: The effects of bacterial cell characteristics and particulate properties.

PubMed

Liang, Xiao; Liao, Chunyu; Soupir, Michelle L; Jarboe, Laura R; Thompson, Michael L; Dixon, Philip M

2017-01-01

E. coli bacteria move in streams freely in a planktonic state or attached to suspended particulates. Attachment is a dynamic process, and the fraction of attached microorganisms is thought to be affected by both bacterial characteristics and particulate properties. In this study, we investigated how the properties of cell surfaces and stream particulates influence attachment. Attachment assays were conducted for 77 E. coli strains and three model particulates (ferrihydrite, Ca-montmorillonite, or corn stover) under environmentally relevant conditions. Surface area, particle size distribution, and total carbon content were determined for each type of particulate. Among the three particulates, attachment fractions to corn stover were significantly larger than the attachments to 2-line ferrihydrite (p-value = 0.0036) and Ca-montmorillonite (p-value = 0.022). Furthermore, attachment to Ca-montmorillonite and corn stover was successfully modeled by a Generalized Additive Model (GAM) using cell characteristics as predictor variables. The natural logarithm of the net charge on the bacterial surface had a significant, positive, and linear impact on the attachment of E. coli bacteria to Ca-montmorillonite (p-value = 0.013), but it did not significantly impact the attachment to corn stover (p-value = 0.36). The large diversities in cell characteristics among 77 E. coli strains, particulate properties, and attachment fractions clearly demonstrated the inadequacy of using a static parameter or linear coefficient to predict the attachment behavior of E. coli in stream water quality models.
Validating a new device for measuring tear evaporation rates.

PubMed

Rohit, Athira; Ehrmann, Klaus; Naduvilath, Thomas; Willcox, Mark; Stapleton, Fiona

2014-01-01

To calibrate and validate a commercially available dermatology instrument to measure tear evaporation rate of contact lens wearers. A dermatology instrument was modified by attaching a swim goggle cup such that the cup sealed around the eye socket. Results for the unmodified instrument are dependent on probe area and enclosed volume. Calibration curves were established using a model eye, to account for individual variations in chamber volume and exposed area. Fifteen participants were recruited and the study included a contact lens wear and a no contact lens wear stage. Day and diurnal variation of the measurements were assessed by taking the measurement three times a day over 2 days. The coefficient of repeatability of the measurement was calculated and a linear mixed model assessed the influence of humidity, temperature, contact lens wear, day and diurnal variations on tear evaporation rate. The associations between variables were assessed using Pearson correlation coefficient. Absolute evaporation rates with and without contact lens wear were calculated based on the new calibration. The measurements were most repeatable during the evening with no lens wear (COR = 49 g m⁻² h) and least repeatable during the evening with contact lens wear (COR = 93 g m⁻² h). Humidity (p = 0.007), and contact lens wear (p < 0.01), significantly affected the tear evaporation rate. However, temperature (p = 0.54) diurnal variation (p = 0.85) and different days (p = 0.65) had no significant effect after controlling for humidity. Tear evaporation rates can be measured using a modified dermatology instrument. Measurements were higher and more variable with lens wear consistent with previous literature. Control of environmental conditions is important as a higher humidity results in a reduced evaporation rate. © 2013 The Authors Ophthalmic & Physiological Optics © 2013 The College of Optometrists.
Individual risk factors for physician boundary violations: the role of attachment style, childhood trauma and maladaptive beliefs.

PubMed

MacDonald, Kai; Sciolla, Andrés F; Folsom, David; Bazzo, David; Searles, Chris; Moutier, Christine; Thomas, Michael L; Borton, Katherine; Norcross, Bill

2015-01-01

The assessment and remediation of boundary-challenged health care professionals is enhanced through examination of individual risk factors. We assessed three such factors - attachment style, childhood trauma and maladaptive beliefs - in 100 attendees (mostly physicians) of a continuing medical education (CME) professional boundaries course. We propose a theoretical model that draws a causal arc from childhood maltreatment through insecure attachment and maladaptive beliefs to elevated risk for boundary violations. We administered the Experiences in Close Relationships Questionnaire Revised (ECR-R), Childhood Trauma Questionnaire (CTQ) and Young Schema Questionnaire (YSQ) to 100 health care professionals attending a CME course on professional boundaries. Experts rated participant autobiographies to determine attachment style and early adversities. Correlations and relationships between self-ratings and expert ratings and among different risk factors were examined. One fifth of participants reported moderate to severe childhood abuse; sixty percent reported moderate to severe emotional neglect. Despite this, average attachment anxiety and attachment avoidance were low, and more than half of participants were rated "secure" by experts. Childhood maltreatment was correlated with attachment anxiety and avoidance and predicted expert-rated insecure attachment and maladaptive beliefs. Our findings support a potential link between childhood adversity and boundary difficulties, partly mediated by insecure attachment and early maladaptive beliefs. Furthermore, these results suggest that boundary education programs and professional wellness programs may be enhanced with a focus on sequelae of childhood maltreatment, attachment and common maladaptive thinking patterns. Copyright © 2015 Elsevier Inc. All rights reserved.
Modeling fecal bacteria transport and retention in agricultural and urban soils under saturated and unsaturated flow conditions.

PubMed

Balkhair, Khaled S

2017-03-01

Pathogenic bacteria, that enter surface water bodies and groundwater systems through unmanaged wastewater land application, pose a great risk to human health. In this study, six soil column experiments were conducted to simulate the vulnerability of agricultural and urban field soils for fecal bacteria transport and retention under saturated and unsaturated flow conditions. HYDRUS-1D kinetic attachment and kinetic attachment-detachment models were used to simulate the breakthrough curves of the experimental data by fitting model parameters. Results indicated significant differences in the retention and drainage of bacteria between saturated and unsaturated flow condition in the two studied soils. Flow under unsaturated condition retained more bacteria than the saturated flow case. The high bacteria retention in the urban soil compared to agricultural soil is ascribed not only to the dynamic attachment and sorption mechanisms but also to the greater surface area of fine particles and low flow rate. All models simulated experimental data satisfactorily under saturated flow conditions; however, under variably saturated flow, the peak concentrations were overestimated by the attachment-detachment model and underestimated by the attachment model with blocking. The good match between observed data and simulated concentrations by the attachment model which was supported by the Akaike information criterion (AIC) for model selection indicates that the first-order attachment coefficient was sufficient to represent the quantitative and temporal distribution of bacteria in the soil column. On the other hand, the total mass balance of the drained and retained bacteria in all transport experiments was in the range of values commonly found in the literature. Regardless of flow conditions and soil texture, most of the bacteria were retained in the top 12 cm of the soil column. The approaches and the models used in this study have proven to be a good tool for simulating fecal bacteria transport under a variety of initial and boundary flow conditions, hence providing a better understanding of the transport mechanism of bacteria as well as soil removal efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.
Biofilm development in fixed bed biofilm reactors: experiments and simple models for engineering design purposes.

PubMed

Szilágyi, N; Kovács, R; Kenyeres, I; Csikor, Zs

2013-01-01

Biofilm development in a fixed bed biofilm reactor system performing municipal wastewater treatment was monitored aiming at accumulating colonization and maximum biofilm mass data usable in engineering practice for process design purposes. Initially a 6 month experimental period was selected for investigations where the biofilm formation and the performance of the reactors were monitored. The results were analyzed by two methods: for simple, steady-state process design purposes the maximum biofilm mass on carriers versus influent load and a time constant of the biofilm growth were determined, whereas for design approaches using dynamic models a simple biofilm mass prediction model including attachment and detachment mechanisms was selected and fitted to the experimental data. According to a detailed statistical analysis, the collected data have not allowed us to determine both the time constant of biofilm growth and the maximum biofilm mass on carriers at the same time. The observed maximum biofilm mass could be determined with a reasonable error and ranged between 438 gTS/m(2) carrier surface and 843 gTS/m(2), depending on influent load, and hydrodynamic conditions. The parallel analysis of the attachment-detachment model showed that the experimental data set allowed us to determine the attachment rate coefficient which was in the range of 0.05-0.4 m d(-1) depending on influent load and hydrodynamic conditions.
Roles of ionic strength and biofilm roughness on adhesion kinetics of Escherichia coli onto groundwater biofilm grown on PVC surfaces

PubMed Central

Janjaroen, Dao; Ling, Fangqiong; Monroy, Guillermo; Derlon, Nicolas; Mogenroth, Eberhard; Boppart, Stephen A.; Liu, Wen-Tso; Nguyen, Thanh H.

2013-01-01

Mechanisms of Escherichia coli attachment on biofilms grown on PVC coupons were investigated. Biofilms were grown in CDC reactors using groundwater as feed solution over a period up to 27 weeks. Biofilm physical structure was characterized at the micro- and meso-scales using Scanning Electron Microscopy (SEM) and Optical Coherence Tomography (OCT), respectively. Microbial community diversity was analyzed with Terminal Restricted Fragment Length Polymorphism (T-RFLP). Both physical structure and microbial community diversity of the biofilms were shown to be changing from 2 weeks to 14 weeks, and became relatively stable after 16 weeks. A parallel plate flow chamber coupled with an inverted fluorescent microscope was also used to monitor the attachment of fluorescent microspheres and E. coli on clean PVC surfaces and biofilms grown on PVC surfaces for different ages. Two mechanisms of E. coli attachment were identified. The adhesion rate coefficients (kd) of E. coli on nascent PVC surfaces and 2-week biofilms increased with ionic strength. However, after biofilms grew for 8 weeks, the adhesion was found to be independent of solution chemistry. Instead, a positive correlation between kd and biofilm roughness as determined by OCT was obtained, indicating that the physical structure of biofilms could play an important role in facilitating the adhesion of E. coli cells. PMID:23497979
Attachment style and its relationship to working alliance in the supervision of British clinical psychology trainees.

PubMed

Dickson, Joanne M; Moberly, Nicholas J; Marshall, Yehuda; Reilly, James

2011-01-01

Although the supervisory relationship is thought to be critical in training clinical psychologists, little is known about factors affecting the supervisory alliance. We conducted an Internet survey of British clinical doctoral trainees (N = 259) in which participants rated their supervisory working alliance, parental style during childhood, pathological adult attachment behaviours and attachment style for themselves and their supervisors. Trainees' ratings of the working alliance were associated with perceptions of supervisors' attachment style, but not with perceptions of trainees' own attachment styles. Path analysis supported a causal chain linking parental indifference, compulsive self-reliance, insecure supervisor attachment style and lower ratings of the working alliance. Our results broadly replicate data from a US sample and suggest that attachment theory is helpful in understanding clinical supervisory processes. Copyright © 2010 John Wiley & Sons, Ltd.
Model-derived dose rates per unit concentration of radon in air in a generic plant geometry.

PubMed

Vives i Batlle, J; Smith, A; Vives-Lynch, S; Copplestone, D; Pröhl, G; Strand, T

2011-11-01

A model for the derivation of dose rates per unit radon concentration in plants was developed in line with the activities of a Task Group of the International Commission on Radiological Protection (ICRP), aimed at developing more realistic dosimetry for non-human biota. The model considers interception of the unattached and attached fractions of the airborne radon daughters by plant stomata, diffusion of radon gas through stomata, permeation through the plant's epidermis and translocation of deposited activity to plant interior. The endpoint of the model is the derivation of dose conversion coefficients relative to radon gas concentration at ground level. The model predicts that the main contributor to dose is deposition of (214)Po α-activity on the plant surface and that diffusion of radon daughters through the stomata is of relatively minor importance; hence, daily variations have a small effect on total dose.
Associations between adult attachment and: oral health-related quality of life, oral health behaviour, and self-rated oral health.

PubMed

Meredith, Pamela; Strong, Jenny; Ford, Pauline; Branjerdporn, Grace

2016-02-01

Although adult attachment theory has been revealed as a useful theoretical framework for understanding a range of health parameters, the associations between adult attachment patterns and a range of oral health parameters have not yet been examined. The aim of this study was to examine potential associations between attachment insecurity and: (1) oral health-related quality of life (OHRQoL), (2) oral health behaviours, and (3) self-rated oral health. In association with this aim, sample characteristics were compared with normative data. The sample in this cross-sectional study was comprised of 265 healthy adults, recruited via convenience sampling. Data were collected on attachment patterns (Experiences in Close Relationships Scale-Short Form, ECR-S), OHRQoL (Oral Health Impact Profile-14, OHIP-14), oral health behaviours (modified Dental Neglect Scale, m-DNS), and self-rated oral health (one-item global rating of oral health). Multivariate regression models were performed. Both dimensions of attachment insecurity were associated with lowered use of favourable dental visiting behaviours, as well as decreased OHRQoL for both overall well-being and specific aspects of OHRQoL. Attachment avoidance was linked with diminished self-rated oral health. This study supports the potential value of an adult attachment framework for understanding a range of oral health parameters. The assessment of a client's attachment pattern may assist in the identification of people who are at risk of diminished OHRQoL, less adaptive dental visiting behaviours, or poorer oral health. Further research in this field may inform ways in which attachment approaches can enhance oral health-related interventions.

Knightsat Flight Design Review

DTIC Science & Technology

2007-08-03

spring loaded hinges were obtained from McMaster under part number 15205A42. The fasteners used to attach each shutter to its corresponding hinge were... Coefficient of thermal expansion) is fairly well matched to the cell’s germanium substrate. Copper is not a good choice since it expands and contracts...Temperature: K Ground Station Transmission Line Temp.: 290 K Ground Station Sky Temperature: 450 K G.S. Transmission Line Coefficient : 0.7943 Ground Station
Effect of the coefficient of friction and tightening speed on the preload induced at the dental implant complex with the finite element method.

PubMed

Bulaqi, Haddad Arabi; Mousavi Mashhadi, Mahmoud; Geramipanah, Farideh; Safari, Hamed; Paknejad, Mojgan

2015-05-01

To prevent screw loosening, a clear understanding of the factors influencing secure preload is necessary. The purpose of this study was to investigate the effect of coefficient of friction and tightening speed on screw tightening based on energy distribution method with exact geometric modeling and finite element analysis. To simulate the proper boundary conditions of the screw tightening process, the supporting bone of an implant was considered. The exact geometry of the implant complex, including the Straumann dental implant, direct crown attachment, and abutment screw were modeled with Solidworks software. Abutment screw/implant and implant/bone interfaces were designed as spiral thread helixes. The screw-tightening process was simulated with Abaqus software, and to achieve the target torque, an angular displacement was applied to the abutment screw head at different coefficients of friction and tightening speeds. The values of torque, preload, energy distribution, elastic energy, and efficiency were obtained at the target torque of 35 Ncm. Additionally, the torque distribution ratio and preload simulated values were compared to theoretically predicted values. Upon reducing the coefficient of friction and enhancing the tightening speed, the angle of turn increased at the target torque. As the angle of turn increased, the elastic energy and preload also increased. Additionally, by increasing the coefficient of friction, the frictional dissipation energy increased but the efficiency decreased, whereas the increase in tightening speed insignificantly affected efficiency. The results of this study indicate that the coefficient of friction is the most influential factor on efficiency. Increasing the tightening speed lowered the response rate to the frictional resistance, thus diminishing the coefficient of friction and slightly increasing the preload. Increasing the tightening speed has the same result as reducing the coefficient of friction. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
A short-term longitudinal study of correlates and sequelae of attachment security in autism

PubMed Central

Rozga, Agata; Hesse, Erik; Main, Mary; Duschinsky, Robbie; Beckwith, Leila; Sigman, Marian

2018-01-01

ABSTRACT In this short-term longitudinal study, 30 preschool-aged children with autism were first observed in Ainsworth’s Strange Situation Procedure and, separately, interacting with the primary caregiver in the home. One year later, each child completed both a developmental assessment and an observational assessment of empathic responding. Behaviors typical for children with autism were distinguished from behaviors suggestive of relationally based attachment disorganization. Forty-five percent of the children were classified as securely attached. The secure group demonstrated language skills superior to those of the insecurely attached group, concurrently and during the follow-up. Compared to parents of children who were insecurely attached, parents of securely attached children were rated as more sensitive. Compared to both organized insecure and disorganized children, secure children were rated as more responsive to an examiner’s apparent distress during the follow-up relative to their ratings at intake, whereas empathy ratings of children with insecure classifications did not increase. Importantly, attachment security was associated with empathy above and beyond the contribution of children’s language level. These results indicate that the sequelae of attachment security in autism may be similar to those documented for typically developing children. PMID:28959921
Attachment Style and Resiliency in Patients with Obsessive-Compulsive Personality Disorder

PubMed Central

Zakiei, Ali; Farnia, Vahid; Khkian, Zinab; Shakeri, Jalal; Golshani, Sanobar

2017-01-01

Background The goal of the present study was to determine the relationships between attachment styles and resiliency in obsessive-compulsive personality disorder. Methods A random sample of 260 subjects was obtained from the population of undergraduate students of the Nour Branch of Islamic Azad University, which is located in Mazandaran, and these subjects were enrolled in this descriptive and correlational study. The collected data included the subjects' responses to an adult attachment style questionnaire, resilience scale, and obsessive-compulsive personality disorder questionnaire. The data were analyzed with Pearson correlation coefficient indices and multiple regressions. Results The results of the data analysis showed a positive correlation (relationship) between ambivalent/avoidant attachment styles and obsessive-compulsive personality disorder and a negative correlation between resilience and obsessive-compulsive personality disorder. Furthermore, these results demonstrated that attachment style and resiliency can predict obsessive-compulsive personality disorder. In addition, no significant relationships were found between the demographic variables (convertibles) and obsessive-compulsive personality disorder. Conclusion These results suggested that attachment style and resiliency contribute to the development of obsessive-compulsive personality disorder. PMID:28197331
Attachment Style and Resiliency in Patients with Obsessive-Compulsive Personality Disorder.

PubMed

Zakiei, Ali; Alikhani, Mostafa; Farnia, Vahid; Khkian, Zinab; Shakeri, Jalal; Golshani, Sanobar

2017-01-01

The goal of the present study was to determine the relationships between attachment styles and resiliency in obsessive-compulsive personality disorder. A random sample of 260 subjects was obtained from the population of undergraduate students of the Nour Branch of Islamic Azad University, which is located in Mazandaran, and these subjects were enrolled in this descriptive and correlational study. The collected data included the subjects' responses to an adult attachment style questionnaire, resilience scale, and obsessive-compulsive personality disorder questionnaire. The data were analyzed with Pearson correlation coefficient indices and multiple regressions. The results of the data analysis showed a positive correlation (relationship) between ambivalent/avoidant attachment styles and obsessive-compulsive personality disorder and a negative correlation between resilience and obsessive-compulsive personality disorder. Furthermore, these results demonstrated that attachment style and resiliency can predict obsessive-compulsive personality disorder. In addition, no significant relationships were found between the demographic variables (convertibles) and obsessive-compulsive personality disorder. These results suggested that attachment style and resiliency contribute to the development of obsessive-compulsive personality disorder.
Substrate effects on endothelial cell adherence rates.

PubMed

Scott, W J; Mann, P

1990-01-01

Endothelial cell attachment to a synthetic substrate was studied using an in vitro model system. Attachment rate was defined as the number of tritium-labeled endothelial cells attached to a synthetic substrate after 30 minutes. The surface of the synthetic substrate was chemically modified with either laminin or fibronectin. Labeled endothelial cells attached more rapidly to synthetic substrate, chemically modified with biomolecules, as compared with the untreated substrate controls. Unlabeled endothelial cells were grown to confluency on a second set of modified and untreated substrates. The cells were removed with 1% Triton, and the rate of re-endothelialization with tritium-labeled endothelial cells was determined. The rate was 11-13 times that of the same cells on untreated substrate. These data confirm that biomolecules increase the attachment rate of endothelial cells to synthetic substrate, and also suggest that endothelial cells may secrete a Triton-insoluble product (Sigma, St. Louis, MO) into subendothelial matrix that increases re-endothelialization.
Was that cheating? Perceptions vary by sex, attachment anxiety, and behavior.

PubMed

Kruger, Daniel J; Fisher, Maryanna L; Edelstein, Robin S; Chopik, William J; Fitzgerald, Carey J; Stout, Sarah L

2013-02-13

We generated an inventory of 27 interpersonal behaviors and examined the extent to which participants judged each behavior as cheating on a long-term partner. We predicted variation in these judgments based on participant sex and attachment insecurity. Ratings for items ranged considerably; participants rated sexual behaviors as most indicative of cheating, then erotic behaviors, followed by behaviors consistent with a romantic relationship, and then behaviors related to financial support. Women rated ten items higher than did men, and men's ratings were higher on a minor financial support item. Higher attachment anxiety was associated with higher ratings for 18 of 27 behaviors; higher attachment avoidance was associated with lower scores on five items and higher scores on one item. Principle Axis Factoring identified three dimensions; sexual interaction, behaviors indicating close relationships, and casual social interaction. We discuss these results using the framework of attachment theory and sex-specific mating strategies.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Pirrung, Georg; Madsen, Helge; Schreck, Scott

Current fast aeroelastic wind turbine codes suitable for certification lack an induction model for standstill conditions. A trailed vorticity model previously used as addition to a blade element momentum theory based aerodynamic model in normal operation has been extended to allow computing the induced velocities in standstill. The model is validated against analytical results for an elliptical wing in constant inflow and against stand still measurements from the NREL/NASA Phase VI unsteady experiment. The extended model obtains good results in case of the elliptical wing, but underpredicts the steady loading for the Phase VI blade in attached flow. The predictionmore » of the dynamic force coefficient loops from the Phase VI experiment is improved by the trailed vorticity modeling in both attached flow and stall in most cases. The exception is the tangential force coefficient in stall, where the codes and measurements deviate and no clear improvement is visible.« less
Trailed vorticity modeling for aeroelastic wind turbine simulations in stand still

DOE PAGES

Pirrung, Georg; Madsen, Helge; Schreck, Scott

2016-10-03

Current fast aeroelastic wind turbine codes suitable for certification lack an induction model for standstill conditions. A trailed vorticity model previously used as addition to a blade element momentum theory based aerodynamic model in normal operation has been extended to allow computing the induced velocities in standstill. The model is validated against analytical results for an elliptical wing in constant inflow and against stand still measurements from the NREL/NASA Phase VI unsteady experiment. The extended model obtains good results in case of the elliptical wing, but underpredicts the steady loading for the Phase VI blade in attached flow. The predictionmore » of the dynamic force coefficient loops from the Phase VI experiment is improved by the trailed vorticity modeling in both attached flow and stall in most cases. The exception is the tangential force coefficient in stall, where the codes and measurements deviate and no clear improvement is visible.« less
Adolescents' strengths and difficulties: approach to attachment styles.

PubMed

Keskin, G; Cam, O

2010-06-01

This research is a descriptive field study conducted in order to investigate the relationship between adolescent difficulties and the attachment style. The study aims to investigate the relationship between adolescent attachment style and strength and difficulties in Turkey. Children attachment style and difficulties pattern in the group of adolescents aged 11-16 years old were compared with each other. Several different questionnaires, including The Strength and Difficulties Questionnaire, The Relationship Scale Questionnaire were applied to 384 (mean age 12.10 +/- 1.4 years) adolescents. The data were analysed using descriptive statistics, Pearson correlation coefficients, anova, t-test, Kruskall Wallis and effect sizes. The adolescent secure attachment style was associated with increased levels of prosocial behaviour, decreased levels of emotional symptoms, hyperactivity/inattention, peer relationship problems, conduct problems, total difficulties scores. The adolescent fearful attachment style was associated with increased levels of emotional symptoms, and total difficulties scores. The adolescent dismissing attachment style was significantly associated with higher levels of emotional symptoms, hyperactivity/inattention, total difficulties scores and lower levels of prosocial behaviour. Adolescent strengths and difficulties are associated with their attachment style. Insecure attachment styles of dismissing and fearful were associated with increased mental symptom reporting. It is suggested that further studies may illuminate the clinical value of the attachment disorder and quantify parental contribution to psychopathology. Giving the therapeutic, structured mental support programme to adolescents that have attachment problems could be beneficial in improving mental status of these individuals.
Measurements of the Rotation of the Flagellar Motor by Bead Assay.

PubMed

Kasai, Taishi; Sowa, Yoshiyuki

2017-01-01

The bacterial flagellar motor is a reversible rotary nano-machine powered by the ion flux across the cytoplasmic membrane. Each motor rotates a long helical filament that extends from the cell body at several hundreds revolutions per second. The output of the motor is characterized by its generated torque and rotational speed. The torque can be calculated as the rotational frictional drag coefficient multiplied by the angular velocity. Varieties of methods, including a bead assay, have been developed to measure the flagellar rotation rate under various load conditions on the motor. In this chapter, we describe a method to monitor the motor rotation through a position of a 1 μm bead attached to a truncated flagellar filament.
Attachment anxiety benefits from security priming: Evidence from working memory performance

PubMed Central

2018-01-01

The present study investigates the relationship between the attachment dimensions (anxious vs. avoidance) and the cognitive performance of individuals, specifically whether the attachment dimensions would predict the working memory (WM) performance. In the n-back task, reflecting the WM capacity, both attachment related and non-attachment related words were used. Participants were randomly assigned into two groups that received either the secure or the neutral subliminal priming. In the secure priming condition, the aim was to induce sense of security by presenting secure attachment words prior to the n-back task performance. In neutral priming condition, neutral words that did not elicit sense of security were presented. Structural equation modeling revealed divergent patterns for attachment anxiety and avoidance dimensions under the different priming conditions. In neutral priming condition, WM performance declined in terms of capacity in the n-back task for individuals who rated higher levels of attachment anxiety. However in the secure priming condition, WM performance was boosted in the n-back task for individuals who rated higher levels of attachment anxiety. In other words, the subliminal priming of the security led to increased WM capacity of individuals who rated higher levels of attachment anxiety. This effect, however, was not observed for higher levels of attachment avoidance. Results are discussed along the lines of hyperactivation and deactivation strategies of the attachment system. PMID:29522549
Electron attachment to CF3 and CF3Br at temperatures up to 890 K: experimental test of the kinetic modeling approach.

PubMed

Shuman, Nicholas S; Miller, Thomas M; Viggiano, Albert A; Troe, Jürgen

2013-05-28

Thermal rate constants and product branching fractions for electron attachment to CF3Br and the CF3 radical have been measured over the temperature range 300-890 K, the upper limit being restricted by thermal decomposition of CF3Br. Both measurements were made in Flowing Afterglow Langmuir Probe apparatuses; the CF3Br measurement was made using standard techniques, and the CF3 measurement using the Variable Electron and Neutral Density Attachment Mass Spectrometry technique. Attachment to CF3Br proceeds exclusively by the dissociative channel yielding Br(-), with a rate constant increasing from 1.1 × 10(-8) cm(3) s(-1) at 300 K to 5.3 × 10(-8) cm(3) s(-1) at 890 K, somewhat lower than previous data at temperatures up to 777 K. CF3 attachment proceeds through competition between associative attachment yielding CF3 (-) and dissociative attachment yielding F(-). Prior data up to 600 K showed the rate constant monotonically increasing, with the partial rate constant of the dissociative channel following Arrhenius behavior; however, extrapolation of the data using a recently proposed kinetic modeling approach predicted the rate constant to turn over at higher temperatures, despite being only ~5% of the collision rate. The current data agree well with the previous kinetic modeling extrapolation, providing a demonstration of the predictive capabilities of the approach.
Attachment Status Affects Heart Rate Responses to Experimental Ostracism in Inpatients with Depression

PubMed Central

De Rubeis, Jannika; Sütterlin, Stefan; Lange, Diane; Pawelzik, Markus; van Randenborgh, Annette; Victor, Daniela; Vögele, Claus

2016-01-01

Depression is assumed to be both a risk factor for rejection and a result of it, and as such constitutes an important factor in rejection research. Attachment theory has been applied to understand psychological disorders, such as depression, and can explain individual differences in responses to rejection. Research on autonomic nervous system activity to rejection experiences has been contradictory, with opposing strings of argumentation (activating vs. numbing). We investigated autonomic nervous system-mediated peripheral physiological responses (heart rate) to experimentally manipulated ostracism (Cyberball) in 97 depressed patients with organized (n = 52) and disorganized attachment status (n = 45). Controlling for baseline mean heart rate levels, depressed patients with disorganized attachment status responded to ostracism with significantly higher increases in heart rate than depressed patients with organized attachment status (p = .029; ηp2 = .051). These results suggest that attachment status may be a useful indicator of autonomic responses to perceived social threat, which in turn may affect the therapeutic process and the patient-therapist relationship. PMID:26943924
Individual risk factors for physician boundary violations: the role of attachment style, childhood trauma and maladaptive beliefs.

PubMed

MacDonald, Kai; Sciolla, Andrés F; Folsom, David; Bazzo, David; Searles, Chris; Moutier, Christine; Thomas, Michael L; Borton, Katherine; Norcross, Bill

2015-01-01

The assessment and remediation of boundary-challenged healthcare professionals is enhanced through examination of individual risk factors. We assessed three such factors--attachment style, childhood trauma and maladaptive beliefs--in 100 attendees (mostly physicians) of a CME professional boundaries course. We propose a theoretical model which draws a causal arc from childhood maltreatment through insecure attachment and maladaptive beliefs to elevated risk for boundary violations. We administered the Experiences in Close Relationship Questionnaire (ECR-R), Childhood Trauma Questionnaire (CTQ), and Young Schema Questionnaire (YSQ) to 100 healthcare professionals (mostly physicians) attending a CME course on professional boundaries. Experts rated participant autobiographies to determine attachment style and early adversities. Correlations and relationships among self- and expert ratings and between different risk factors were examined. Five percent of participants reported CTQ total scores in the moderate to severe range; eleven percent reported moderate to severe emotional neglect or emotional abuse. Average attachment anxiety and attachment avoidance were low, and more than half of participants were rated “secure” by experts. Childhood maltreatment was correlated with attachment anxiety and avoidance and predicted expert-rated insecure attachment and maladaptive beliefs. Our findings support a potential link between childhood adversity and boundary difficulties, partly mediated by insecure attachment and early maladaptive beliefs. Furthermore, these results suggest that boundary education programs and professional wellness programs may be enhanced with a focus on sequelae of childhood maltreatment, attachment and common maladaptive thinking patterns.
Benchmark calculations of nonconservative charged-particle swarms in dc electric and magnetic fields crossed at arbitrary angles.

PubMed

Dujko, S; White, R D; Petrović, Z Lj; Robson, R E

2010-04-01

A multiterm solution of the Boltzmann equation has been developed and used to calculate transport coefficients of charged-particle swarms in gases under the influence of electric and magnetic fields crossed at arbitrary angles when nonconservative collisions are present. The hierarchy resulting from a spherical-harmonic decomposition of the Boltzmann equation in the hydrodynamic regime is solved numerically by representing the speed dependence of the phase-space distribution function in terms of an expansion in Sonine polynomials about a Maxwellian velocity distribution at an internally determined temperature. Results are given for electron swarms in certain collisional models for ionization and attachment over a range of angles between the fields and field strengths. The implicit and explicit effects of ionization and attachment on the electron-transport coefficients are considered using physical arguments. It is found that the difference between the two sets of transport coefficients, bulk and flux, resulting from the explicit effects of nonconservative collisions, can be controlled either by the variation in the magnetic field strengths or by the angles between the fields. In addition, it is shown that the phenomena of ionization cooling and/or attachment cooling/heating previously reported for dc electric fields carry over directly to the crossed electric and magnetic fields. The results of the Boltzmann equation analysis are compared with those obtained by a Monte Carlo simulation technique. The comparison confirms the theoretical basis and numerical integrity of the moment method for solving the Boltzmann equation and gives a set of well-established data that can be used to test future codes and plasma models.
Numerical study on the aerodynamic characteristics of both static and flapping wing with attachments

NASA Astrophysics Data System (ADS)

Xie, Lingwang; Zhang, Xingwei; Luo, Pan; Huang, Panpan

2017-10-01

The purpose of this paper is to investigate the aerodynamic mechanism of airfoils under different icing situations which are different icing type, different icing time, and different icing position. Numerical simulation is carried out by using the finite volume method for both static and flapping airfoils, when Reynolds number is kept at 135000. The difference of aerodynamic performance between the airfoil with attachments and without attachments are be investigated by comparing the force coefficients, lift-to-drag ratios and flow field contour. The present simulations reveal that some influences of attachment are similar in the static airfoil and the flapping airfoil. Specifically, the airfoil with the attachment derived from glaze ice type causes the worse aerodynamic performance than that derived from rime ice type. The longer the icing time, the greater influence of aerodynamic performance the attachment causes. The attachments on the leading-edge have the greater influence of aerodynamic performance than other positions. Moreover, there are little differences between the static airfoil and the flapping airfoil. Compared with the static airfoil, the flapping airfoil which attachment located on the trailing edge causes a worse aerodynamic performance. Both attachments derived from rime ice type and glaze ice type all will deteriorate the aerodynamic performance of the asymmetrical airfoils. Present work provides the systematic and comprehensive study about icing blade which is conducive to the development of the wind power generation technology.
Determination of the profile of DO and its mass transferring coefficient in a biofilm reactor packed with semi-suspended bio-carriers.

PubMed

Tang, Bing; Song, Haoliang; Bin, Liying; Huang, Shaosong; Zhang, Wenxiang; Fu, Fenglian; Zhao, Yiliang; Chen, Qianyu

2017-10-01

The work aims at illustrating the profile of DO and its mass transferring process in a biofilm reactor packed with a novel semi-suspended bio-carrier, and further revealing the main factors that influence the mass transferring coefficient of DO within the biofilm. Results showed that the biofilm was very easy to attach and grow on the semi-suspended bio-carrier, which obviously changed the DO profile inside and outside the biofilm. The semi-suspended bio-carrier caused three different mass transfer zones occurring in the bioreactor, including the zones of bulk solution, boundary layer and biofilm, in which, the boundary layer zone had an obvious higher mass transfer resistance. Increasing the aeration rate might improve the hydrodynamic conditions in the bioreactor and accelerate the mass transfer of DO, but it also detached the biofilm from the surface of bio-carrier, which reduced the consumption of DO, and accordingly, decreased the DO gradient in the bioreactor. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pilot Testing of a Sampling Methodology for Assessing Seed Attachment Propensity and Transport Rate in a Soil Matrix Carried on Boot Soles and Bike Tires.

PubMed

Hardiman, Nigel; Dietz, Kristina Charlotte; Bride, Ian; Passfield, Louis

2017-01-01

Land managers of natural areas are under pressure to balance demands for increased recreation access with protection of the natural resource. Unintended dispersal of seeds by visitors to natural areas has high potential for weedy plant invasions, with initial seed attachment an important step in the dispersal process. Although walking and mountain biking are popular nature-based recreation activities, there are few studies quantifying propensity for seed attachment and transport rate on boot soles and none for bike tires. Attachment and transport rate can potentially be affected by a wide range of factors for which field testing can be time-consuming and expensive. We pilot tested a sampling methodology for measuring seed attachment and transport rate in a soil matrix carried on boot soles and bike tires traversing a known quantity and density of a seed analog (beads) over different distances and soil conditions. We found % attachment rate on boot soles was much lower overall than previously reported, but that boot soles had a higher propensity for seed attachment than bike tires in almost all conditions. We believe our methodology offers a cost-effective option for researchers seeking to manipulate and test effects of different influencing factors on these two dispersal vectors.
Pilot Testing of a Sampling Methodology for Assessing Seed Attachment Propensity and Transport Rate in a Soil Matrix Carried on Boot Soles and Bike Tires

NASA Astrophysics Data System (ADS)

Hardiman, Nigel; Dietz, Kristina Charlotte; Bride, Ian; Passfield, Louis

2017-01-01

Land managers of natural areas are under pressure to balance demands for increased recreation access with protection of the natural resource. Unintended dispersal of seeds by visitors to natural areas has high potential for weedy plant invasions, with initial seed attachment an important step in the dispersal process. Although walking and mountain biking are popular nature-based recreation activities, there are few studies quantifying propensity for seed attachment and transport rate on boot soles and none for bike tires. Attachment and transport rate can potentially be affected by a wide range of factors for which field testing can be time-consuming and expensive. We pilot tested a sampling methodology for measuring seed attachment and transport rate in a soil matrix carried on boot soles and bike tires traversing a known quantity and density of a seed analog (beads) over different distances and soil conditions. We found % attachment rate on boot soles was much lower overall than previously reported, but that boot soles had a higher propensity for seed attachment than bike tires in almost all conditions. We believe our methodology offers a cost-effective option for researchers seeking to manipulate and test effects of different influencing factors on these two dispersal vectors.

Gas engineering studies for high pressure self-sustained diffuse discharge closing switches

NASA Astrophysics Data System (ADS)

Hunter, S. R.; Christophorou, L. G.; Carter, J. G.

The operating voltage and discharge stability of diffuse discharges for fast-closing switch applications are critically dependent on the variation of the ionization (alpha/N) and attachment (eta/N) coefficients with E/N (gas density normalized electric field strength). Gases and gas mixtures which possess low (E/N)/sub lim/ values (i.e., the E/N value when anti alpha/N = alpha/N - eta/N = 0) and effective ionization coefficients, anti alpha/N, which vary slowly with E/N near (E/N)(sub lim) lead to lower voltage (i.e., more efficient) operation with increased discharge stability. Several gas mixtures with these characteristics are discussed. It is argued that further improvements in switch efficiency and discharge stability can be obtained by adding a low ionization onset gas additive to these binary mixtures, such that at low E/N, alpha/N is greater than eta/N, while at higher E/N, eta/N is greater than alpha/N over a restricted E/N range. Several low ionization onset gas additives are suggested and the electron attachment and ionization coefficients in selected gas mixtures which possess these desirable characteristics are given.
Seal assembly for materials with different coefficients of thermal expansion

DOEpatents

Minford, Eric [Laurys Station, PA

2009-09-01

Seal assembly comprising (a) two or more seal elements, each element having having a coefficient of thermal expansion; and (b) a clamping element having a first segment, a second segment, and a connecting segment between and attached to the first and second segments, wherein the two or more seal elements are disposed between the first and second segments of the clamping element. The connecting segment has a central portion extending between the first segment of the clamping element and the second segment of the clamping element, and the connecting segment is made of a material having a coefficient of thermal expansion. The coefficient of thermal expansion of the material of the connecting segment is intermediate the largest and smallest of the coefficients of thermal expansion of the materials of the two or more seal elements.
Enhanced vbasis laser diode package

DOEpatents

Deri, Robert J.; Chen, Diana; Bayramian, Andy; Freitas, Barry; Kotovsky, Jack

2014-08-19

A substrate having an upper surface and a lower surface is provided. The substrate includes a plurality of v-grooves formed in the upper surface. Each v-groove includes a first side and a second side perpendicular to the first side. A laser diode bar assembly is disposed within each of the v-grooves and attached to the first side. The laser diode bar assembly includes a first adhesion layer disposed on the first side of the v-groove, a metal plate attached to the first adhesion layer, a second adhesion layer disposed over the metal plate, and a laser diode bar attached to the second adhesion layer. The laser diode bar has a coefficient of thermal expansion (CTE) substantially similar to that of the metal plate.
Assessment of bioavailability of soil-sorbed atrazine.

PubMed

Park, Jeong-Hun; Feng, Yucheng; Ji, Pingsheng; Voice, Thomas C; Boyd, Stephen A

2003-06-01

Bioavailability of pesticides sorbed to soils is an important determinant of their environmental fate and impact. Mineralization of sorbed atrazine was studied in soil and clay slurries, and a desorption-biodegradation-mineralization (DBM) model was developed to quantitatively evaluate the bioavailability of sorbed atrazine. Three atrazine-degrading bacteria that utilized atrazine as a sole N source (Pseudomonas sp. strain ADP, Agrobacterium radiobacter strain J14a, and Ralstonia sp. strain M91-3) were used in the bioavailability assays. Assays involved establishing sorption equilibrium in sterile soil slurries, inoculating the system with organisms, and measuring the CO(2) production over time. Sorption and desorption isotherm analyses were performed to evaluate distribution coefficients and desorption parameters, which consisted of three desorption site fractions and desorption rate coefficients. Atrazine sorption isotherms were linear for mineral and organic soils but displayed some nonlinearity for K-saturated montmorillonite. The desorption profiles were well described by the three-site desorption model. In many instances, the mineralization of atrazine was accurately predicted by the DBM model, which accounts for the extents and rates of sorption/desorption processes and assumes biodegradation of liquid-phase, but not sorbed, atrazine. However, for the Houghton muck soil, which manifested the highest sorbed atrazine concentrations, enhanced mineralization rates, i.e., greater than those expected on the basis of aqueous-phase atrazine concentration, were observed. Even the assumption of instantaneous desorption could not account for the elevated rates. A plausible explanation for enhanced bioavailability is that bacteria access the localized regions where atrazine is sorbed and that the concentrations found support higher mineralization rates than predicted on the basis of aqueous-phase concentrations. Characteristics of high sorbed-phase concentration, chemotaxis, and attachment of cells to soil particles seem to contribute to the bioavailability of soil-sorbed atrazine.
Assessment of Bioavailability of Soil-Sorbed Atrazine

PubMed Central

Park, Jeong-Hun; Feng, Yucheng; Ji, Pingsheng; Voice, Thomas C.; Boyd, Stephen A.

2003-01-01

Bioavailability of pesticides sorbed to soils is an important determinant of their environmental fate and impact. Mineralization of sorbed atrazine was studied in soil and clay slurries, and a desorption-biodegradation-mineralization (DBM) model was developed to quantitatively evaluate the bioavailability of sorbed atrazine. Three atrazine-degrading bacteria that utilized atrazine as a sole N source (Pseudomonas sp. strain ADP, Agrobacterium radiobacter strain J14a, and Ralstonia sp. strain M91-3) were used in the bioavailability assays. Assays involved establishing sorption equilibrium in sterile soil slurries, inoculating the system with organisms, and measuring the CO2 production over time. Sorption and desorption isotherm analyses were performed to evaluate distribution coefficients and desorption parameters, which consisted of three desorption site fractions and desorption rate coefficients. Atrazine sorption isotherms were linear for mineral and organic soils but displayed some nonlinearity for K-saturated montmorillonite. The desorption profiles were well described by the three-site desorption model. In many instances, the mineralization of atrazine was accurately predicted by the DBM model, which accounts for the extents and rates of sorption/desorption processes and assumes biodegradation of liquid-phase, but not sorbed, atrazine. However, for the Houghton muck soil, which manifested the highest sorbed atrazine concentrations, enhanced mineralization rates, i.e., greater than those expected on the basis of aqueous-phase atrazine concentration, were observed. Even the assumption of instantaneous desorption could not account for the elevated rates. A plausible explanation for enhanced bioavailability is that bacteria access the localized regions where atrazine is sorbed and that the concentrations found support higher mineralization rates than predicted on the basis of aqueous-phase concentrations. Characteristics of high sorbed-phase concentration, chemotaxis, and attachment of cells to soil particles seem to contribute to the bioavailability of soil-sorbed atrazine. PMID:12788728
A New Instrument for Thermal Electron Attachment at High Temperature: NF3 and CH3Cl Attachment Rate Constants up to 1100 K

DTIC Science & Technology

2009-03-01

attachment at high temperature: NF3 and CH3CI attachment rate constants up to 1100 K >• Q- O o o o 1,a> Bus Thomas M. Miller, l ’ Jeffrey F...Dotan. M. Menendez-Barreto. J. V. Seeley , J. S. Williamson, F. Dale, P. L. Mundis, R. A. Morris, J. F. Paulson, and A. A. Viggiano, Rev. Sci
Psychotherapy process and relationship in the context of a brief attachment-based mother-infant intervention.

PubMed

Woodhouse, Susan S; Lauer, Maria; Beeney, Julie R S; Cassidy, Jude

2015-03-01

The present study investigated links between the observer-rated process of psychotherapy and 2 key psychotherapy relationship constructs (i.e., working alliance and attachment to the therapist) in the context of a brief, attachment-based, home-visiting, mother-infant intervention that aimed to promote later secure infant attachment. Additionally, links between observer ratings of intervener and mother contributions to process were examined. Participants included 85 economically stressed mothers of first-born, 5.5-month-old, temperamentally irritable infants. Therapists included 2 doctoral-level and 4 master's-level home visitors. Observer-rated therapist psychotherapy process variables (i.e., warmth, exploration, and negative attitude) were not linked to maternal ratings of working alliance. Therapist warmth, however, was positively associated with maternal ratings of security of attachment to the therapist, and therapist negative attitude was positively related to maternal ratings of preoccupied-merger attachment to the therapist. As expected, both therapist warmth and exploration were positively associated with both maternal participation and exploration. Therapist negative attitude was inversely related to maternal exploration, but not to maternal participation. Results support the idea that attention to the psychotherapy process and relationship may be important in the context of a brief home-visiting parenting intervention with a nonclinical sample. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Adult Attachment Ratings (AAR): an item response theory analysis.

PubMed

Pilkonis, Paul A; Kim, Yookyung; Yu, Lan; Morse, Jennifer Q

2014-01-01

The Adult Attachment Ratings (AAR) include 3 scales for anxious, ambivalent attachment (excessive dependency, interpersonal ambivalence, and compulsive care-giving), 3 for avoidant attachment (rigid self-control, defensive separation, and emotional detachment), and 1 for secure attachment. The scales include items (ranging from 6-16 in their original form) scored by raters using a 3-point format (0 = absent, 1 = present, and 2 = strongly present) and summed to produce a total score. Item response theory (IRT) analyses were conducted with data from 414 participants recruited from psychiatric outpatient, medical, and community settings to identify the most informative items from each scale. The IRT results allowed us to shorten the scales to 5-item versions that are more precise and easier to rate because of their brevity. In general, the effective range of measurement for the scales was 0 to +2 SDs for each of the attachment constructs; that is, from average to high levels of attachment problems. Evidence for convergent and discriminant validity of the scales was investigated by comparing them with the Experiences of Close Relationships-Revised (ECR-R) scale and the Kobak Attachment Q-sort. The best consensus among self-reports on the ECR-R, informant ratings on the ECR-R, and expert judgments on the Q-sort and the AAR emerged for anxious, ambivalent attachment. Given the good psychometric characteristics of the scale for secure attachment, however, this measure alone might provide a simple alternative to more elaborate procedures for some measurement purposes. Conversion tables are provided for the 7 scales to facilitate transformation from raw scores to IRT-calibrated (theta) scores.
Preventive Interventions and Sustained Attachment Security in Maltreated Children

PubMed Central

Stronach, Erin Pickreign; Toth, Sheree L.; Rogosch, Fred; Cicchetti, Dante

2013-01-01

Thirteen-month-old maltreated infants (n = 137) and their mothers were randomly assigned to one of three conditions: child-parent psychotherapy (CPP), psychoeducational parenting intervention (PPI), and community standard (CS). A fourth group of nonmaltreated infants (n =52) and their mothers served as a normative comparison (NC) group. A prior investigation found that the CPP and PPI groups demonstrated substantial increases in secure attachment at post-intervention, whereas this change was not found in the CS and NC groups. The current investigation involved the analysis of data obtained at a follow-up assessment that occurred 12-months after the completion of treatment. At follow-up, children in the CPP group had higher rates of secure and lower rates of disorganized attachment than did children in the PPI or CS groups. Rates of disorganized attachment did not differ between the CPP and NC groups. Intention-to-treat analyses (ITT) also showed higher rates of secure attachment at follow-up in the CPP group relative to the PPI and CS groups. However, groups did not differ on disorganized attachment. Both primary and ITT analyses demonstrated that maternal reported child behavior problems did not differ among the four groups at the follow-up assessment. This is the first investigation to demonstrate sustained attachment security in maltreated children 12 months after the completion of an attachment theory-informed intervention. Findings also suggest that, while effective in the short term, parenting interventions alone may not be effective in maintaining secure attachment in children over time. PMID:24229539
Attachment to Mothers and Fathers during Middle Childhood: Associations with Child Gender, Grade, and Competence

ERIC Educational Resources Information Center

Diener, Marissa L.; Isabella, Russell A.; Behunin, Melissa G.; Wong, Maria S.

2008-01-01

Attachment relationships of first, third, and fifth graders with their mothers and fathers, and their associations with self-perceived and teacher-rated competence, were investigated. Children rated their attachment security with mothers and fathers using the Kerns security scale. Children's perceptions of academic and peer competence were…
Removal Efficiencies and Attachment Coefficients for Cryptosporidium in Sandy Alluvial Riverbank Sediment

EPA Science Inventory

Riverbank filtration has been shown to be effective at removing viable Cryptosporidium parvum oocysts and, therefore, drinking water systems that employ riverbank filtration may receive additional treatment credits beyond that which they can obtain using traditional engineering a...
Validation of a computer code for analysis of subsonic aerodynamic performance of wings with flaps in combination with a canard or horizontal tail and an application to optimization

NASA Technical Reports Server (NTRS)

Carlson, Harry W.; Darden, Christine M.; Mann, Michael J.

1990-01-01

Extensive correlations of computer code results with experimental data are employed to illustrate the use of a linearized theory, attached flow method for the estimation and optimization of the longitudinal aerodynamic performance of wing-canard and wing-horizontal tail configurations which may employ simple hinged flap systems. Use of an attached flow method is based on the premise that high levels of aerodynamic efficiency require a flow that is as nearly attached as circumstances permit. The results indicate that linearized theory, attached flow, computer code methods (modified to include estimated attainable leading-edge thrust and an approximate representation of vortex forces) provide a rational basis for the estimation and optimization of aerodynamic performance at subsonic speeds below the drag rise Mach number. Generally, good prediction of aerodynamic performance, as measured by the suction parameter, can be expected for near optimum combinations of canard or horizontal tail incidence and leading- and trailing-edge flap deflections at a given lift coefficient (conditions which tend to produce a predominantly attached flow).
Investigating the Influence of the Initial Biomass Distribution and Injection Strategies on Biofilm-Mediated Calcite Precipitation in Porous Media

DOE PAGES

Hommel, Johannes; Lauchnor, Ellen; Gerlach, Robin; ...

2015-12-16

Attachment of bacteria in porous media is a complex mixture of processes resulting in the transfer and immobilization of suspended cells onto a solid surface within the porous medium. However, quantifying the rate of attachment is difficult due to the many simultaneous processes possibly involved in attachment, including straining, sorption, and sedimentation, and the difficulties in measuring metabolically active cells attached to porous media. Preliminary experiments confirmed the difficulty associated with measuring active Sporosarcina pasteurii cells attached to porous media. However, attachment is a key process in applications of biofilm-mediated reactions in the subsurface such as microbially induced calcite precipitation.more » Independent of the exact processes involved, attachment determines both the distribution and the initial amount of attached biomass and as such the initial reaction rate. As direct experimental investigations are difficult, this study is limited to a numerical investigation of the effect of various initial biomass distributions and initial amounts of attached biomass. This is performed for various injection strategies, changing the injection rate as well as alternating between continuous and pulsed injections. The results of this study indicate that, for the selected scenarios, both the initial amount and the distribution of attached biomass have minor influence on the Ca 2+ precipitation efficiency as well as the distribution of the precipitates compared to the influence of the injection strategy. The influence of the initial biomass distribution on the resulting final distribution of the precipitated calcite is limited, except for the continuous injection at intermediate injection rate. But even for this injection strategy, the Ca 2+ precipitation efficiency shows no significant dependence on the initial biomass distribution.« less
Investigating the Influence of the Initial Biomass Distribution and Injection Strategies on Biofilm-Mediated Calcite Precipitation in Porous Media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hommel, Johannes; Lauchnor, Ellen; Gerlach, Robin

Attachment of bacteria in porous media is a complex mixture of processes resulting in the transfer and immobilization of suspended cells onto a solid surface within the porous medium. However, quantifying the rate of attachment is difficult due to the many simultaneous processes possibly involved in attachment, including straining, sorption, and sedimentation, and the difficulties in measuring metabolically active cells attached to porous media. Preliminary experiments confirmed the difficulty associated with measuring active Sporosarcina pasteurii cells attached to porous media. However, attachment is a key process in applications of biofilm-mediated reactions in the subsurface such as microbially induced calcite precipitation.more » Independent of the exact processes involved, attachment determines both the distribution and the initial amount of attached biomass and as such the initial reaction rate. As direct experimental investigations are difficult, this study is limited to a numerical investigation of the effect of various initial biomass distributions and initial amounts of attached biomass. This is performed for various injection strategies, changing the injection rate as well as alternating between continuous and pulsed injections. The results of this study indicate that, for the selected scenarios, both the initial amount and the distribution of attached biomass have minor influence on the Ca 2+ precipitation efficiency as well as the distribution of the precipitates compared to the influence of the injection strategy. The influence of the initial biomass distribution on the resulting final distribution of the precipitated calcite is limited, except for the continuous injection at intermediate injection rate. But even for this injection strategy, the Ca 2+ precipitation efficiency shows no significant dependence on the initial biomass distribution.« less
A Comparison of Unresolved Versus Resolved Status and Its Relationship to Behaviour in Maltreated Adolescents

ERIC Educational Resources Information Center

Webster, Linda; Hackett, Rachelle Kisst

2007-01-01

This exploratory investigation sought both to gain a better understanding of the mental representations of attachment in high-risk, maltreated adolescents and to explain how, if at all, unresolved attachment representations are related to behavioural maladjustment. Parent ratings, self-report ratings and attachment state of mind were obtained from…
Heart Rate Correlates of Attachment Status in Young Mothers and Their Infants.

ERIC Educational Resources Information Center

Zelenko, Marina; Kraemer, Helena; Huffman, Lynne; Gschwendt, Miriam; Pageler, Natalie; Steiner, Hans

2005-01-01

Objective: To explore heart rate (HR) correlates of attachment behavior in young mothers and their infants to generate specific hypotheses and to provide pilot data on which studies to test those hypotheses might be based. Method: Using the strange situation procedure, patterns of attachment were assessed in 41 low-income adolescent mothers and…
Low-Speed Flight Dynamic Tests and Analysis of the Orion Crew Module Drogue Parachute System

NASA Technical Reports Server (NTRS)

Hahne, David E.; Fremaux, C. Michael

2008-01-01

A test of a dynamically scaled model of the NASA Orion Crew Module (CM) with drogue parachutes was conducted in the NASA-Langley 20-Foot Vertical Spin Tunnel. The primary test objective was to assess the ability of the Orion Crew Module drogue parachute system to adequately stabilize the CM and reduce angular rates at low subsonic Mach numbers. Two attachment locations were tested: the current design nominal and an alternate. Experimental results indicated that the alternate attachment location showed a somewhat greater tendency to attenuate initial roll rate and reduce roll rate oscillations than the nominal location. Comparison of the experimental data to a Program To Optimize Simulated Trajectories (POST II) simulation of the experiment yielded results for the nominal attachment point that indicate differences between the low-speed pitch and yaw damping derivatives in the aerodynamic database and the physical model. Comparisons for the alternate attachment location indicate that riser twist plays a significant role in determining roll rate attenuation characteristics. Reevaluating the impact of the alternate attachment points using a simulation modified to account for these results showed significantly reduced roll rate attenuation tendencies when compared to the original simulation. Based on this modified simulation the alternate attachment point does not appear to offer a significant increase in allowable roll rate over the nominal configuration.
Electron attachment to CF{sub 3} and CF{sub 3}Br at temperatures up to 890 K: Experimental test of the kinetic modeling approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shuman, Nicholas S.; Miller, Thomas M.; Viggiano, Albert A.

Thermal rate constants and product branching fractions for electron attachment to CF{sub 3}Br and the CF{sub 3} radical have been measured over the temperature range 300-890 K, the upper limit being restricted by thermal decomposition of CF{sub 3}Br. Both measurements were made in Flowing Afterglow Langmuir Probe apparatuses; the CF{sub 3}Br measurement was made using standard techniques, and the CF{sub 3} measurement using the Variable Electron and Neutral Density Attachment Mass Spectrometry technique. Attachment to CF{sub 3}Br proceeds exclusively by the dissociative channel yielding Br{sup -}, with a rate constant increasing from 1.1 Multiplication-Sign 10{sup -8} cm{sup 3} s{sup -1}more » at 300 K to 5.3 Multiplication-Sign 10{sup -8} cm{sup 3} s{sup -1} at 890 K, somewhat lower than previous data at temperatures up to 777 K. CF{sub 3} attachment proceeds through competition between associative attachment yielding CF{sub 3}{sup -} and dissociative attachment yielding F{sup -}. Prior data up to 600 K showed the rate constant monotonically increasing, with the partial rate constant of the dissociative channel following Arrhenius behavior; however, extrapolation of the data using a recently proposed kinetic modeling approach predicted the rate constant to turn over at higher temperatures, despite being only {approx}5% of the collision rate. The current data agree well with the previous kinetic modeling extrapolation, providing a demonstration of the predictive capabilities of the approach.« less
Development of In-Fiber Reflective Bragg Gratings as Shear Stress Monitors in Aerodynamic Facilities

NASA Technical Reports Server (NTRS)

Parmar, Devendra S.; Sprinkle, Danny R.; Singh, Jag J.

1998-01-01

Bragg gratings centered at nominal wavelengths of 1290 nm and 1300 run were inscribed in a 9/125 microns germano-silicate optical fiber, using continuous wave frequency doubled Ar+ laser radiation at 244 nm. Such gratings have been used extensively as temperature and strain monitors in smart structures. They have, however, never been used for measuring aerodynamic shear stresses. As a test of their sensitivity as shear stress monitors, a Bragg fiber attached to a metal plate was subjected to laminar flows in a glass pipe. An easily measurable large flow-induced wavelength shift (Delta Lambda(sub B)) was observed in the Bragg reflected wavelength. Thereafter, the grating was calibrated by making one time, simultaneous measurements of Delta Lambda(sub B) and the coefficient of skin friction (C(sub f)) with a skin friction balance, as a function of flow rates in a subsonic wind tunnel. Onset of fan-induced transition in the tunnel flow provided a unique flow rate for correlating Delta Lambda(sub B) and (C(sub f) values needed for computing effective modulus of rigidity (N(sub eff)) of the fiber attached to the metal plate. This value Of N(sub eff) is expected to remain constant throughout the elastic stress range expected during the Bragg grating aerodynamic tests. It has been used for calculating the value of Cf at various tunnel speeds, on the basis of measured values of Bragg wavelength shifts at those speeds.
Dissociation coefficients of protein adsorption to nanoparticles as quantitative metrics for description of the protein corona: A comparison of experimental techniques and methodological relevance.

PubMed

Hühn, Jonas; Fedeli, Chiara; Zhang, Qian; Masood, Atif; Del Pino, Pablo; Khashab, Niveen M; Papini, Emanuele; Parak, Wolfgang J

2016-06-01

Protein adsorption to nanoparticles is described as a chemical reaction in which proteins attach to binding sites on the nanoparticle surface. This process is defined by a dissociation coefficient, which tells how many proteins are adsorbed per nanoparticle in dependence of the protein concentration. Different techniques to experimentally determine dissociation coefficients of protein adsorption to nanoparticles are reviewed. Results of more than 130 experiments in which dissociation coefficients have been determined are compared. Data show that different methods, nanoparticle systems, and proteins can lead to significantly different dissociation coefficients. However, we observed a clear tendency of smaller dissociation coefficients upon less negative towards more positive zeta potentials of the nanoparticles. The zeta potential thus is a key parameter influencing protein adsorption to the surface of nanoparticles. Our analysis highlights the importance of the characterization of the parameters governing protein-nanoparticle interaction for quantitative evaluation and objective literature comparison. Copyright © 2015 Elsevier Ltd. All rights reserved.

Attachment Patterns in the Psychotherapy Relationship: Development of the Client Attachment to Therapist Scale.

ERIC Educational Resources Information Center

Mallinckrodt, Brent; And Others

1995-01-01

Describes development of an instrument, the Client Attachment to Therapist Scale (CATS). CATS factors correlated in expected directions with survey measures of object relations, client-rated working alliance, social self-efficacy, and adult attachment. Cluster analysis revealed four types of client attachment. Discusses implications of attachment…
Large-Scale Wind-Tunnel Tests of an Airplane Model with an Unswept, Aspect-Ratio-10 Wing, Two Propellers, and Blowing Flaps

NASA Technical Reports Server (NTRS)

Griffin, Roy N., Jr.; Holzhauser, Curt A.; Weiberg, James A.

1958-01-01

An investigation was made to determine the lifting effectiveness and flow requirements of blowing over the trailing-edge flaps and ailerons on a large-scale model of a twin-engine, propeller-driven airplane having a high-aspect-ratio, thick, straight wing. With sufficient blowing jet momentum to prevent flow separation on the flap, the lift increment increased for flap deflections up to 80 deg (the maximum tested). This lift increment also increased with increasing propeller thrust coefficient. The blowing jet momentum coefficient required for attached flow on the flaps was not significantly affected by thrust coefficient, angle of attack, or blowing nozzle height.
Ceramic blade attachment system

DOEpatents

Boyd, G.L.

1994-12-13

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion. 3 figures.
Application of Navier-Stokes code PAB3D with kappa-epsilon turbulence model to attached and separated flows

NASA Technical Reports Server (NTRS)

Abdol-Hamid, Khaled S.; Lakshmanan, B.; Carlson, John R.

1995-01-01

A three-dimensional Navier-Stokes solver was used to determine how accurately computations can predict local and average skin friction coefficients for attached and separated flows for simple experimental geometries. Algebraic and transport equation closures were used to model turbulence. To simulate anisotropic turbulence, the standard two-equation turbulence model was modified by adding nonlinear terms. The effects of both grid density and the turbulence model on the computed flow fields were also investigated and compared with available experimental data for subsonic and supersonic free-stream conditions.
Children's Representations of Attachment and Positive Teacher-Child Relationships.

PubMed

Veríssimo, Manuela; Torres, Nuno; Silva, Filipa; Fernandes, Carla; Vaughn, Brian E; Santos, António J

2017-01-01

This study was designed to explore whether children's representations of attachment contribute to the co-construction of positive teacher-child relationships. An assessment of verbal intelligence was included as a predictor on the assumption that teachers might perceive themselves as having better relationships with more verbally competent children. Participants were 52 children from two pre-schools, in the district of Lisbon. The Attachment Story Completion Task (ASCT) was used to assess children's attachment security. The PCV-P (a scale developed in portuguese language) was used to describe teacher-child relationships through teachers' ratings of child secure base behavior and emotion regulation and the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-R) was used to access verbal skills. Bivariate correlations showed that the teachers' rating of child secure base behavior was significantly associated with both child attachment security and verbal IQ. In a multiple regression analysis, the overall model R 2 was significant, as was the interaction term showing a moderating effect of attachment security on the relation between verbal IQ and teachers' ratings of secure base. The results suggest that co-construction of a close attachment-relevant relationship with teachers in early childhood is, in part, a function of the security in the context of parent-child attachment, but also of child verbal development.
Children's Representations of Attachment and Positive Teacher–Child Relationships

PubMed Central

Veríssimo, Manuela; Torres, Nuno; Silva, Filipa; Fernandes, Carla; Vaughn, Brian E.; Santos, António J.

2017-01-01

This study was designed to explore whether children's representations of attachment contribute to the co-construction of positive teacher–child relationships. An assessment of verbal intelligence was included as a predictor on the assumption that teachers might perceive themselves as having better relationships with more verbally competent children. Participants were 52 children from two pre-schools, in the district of Lisbon. The Attachment Story Completion Task (ASCT) was used to assess children's attachment security. The PCV-P (a scale developed in portuguese language) was used to describe teacher–child relationships through teachers' ratings of child secure base behavior and emotion regulation and the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-R) was used to access verbal skills. Bivariate correlations showed that the teachers' rating of child secure base behavior was significantly associated with both child attachment security and verbal IQ. In a multiple regression analysis, the overall model R2 was significant, as was the interaction term showing a moderating effect of attachment security on the relation between verbal IQ and teachers' ratings of secure base. The results suggest that co-construction of a close attachment-relevant relationship with teachers in early childhood is, in part, a function of the security in the context of parent-child attachment, but also of child verbal development. PMID:29312099
Attachment styles and clinical communication performance in trainee doctors.

PubMed

Fletcher, Ian; McCallum, Rachel; Peters, Sarah

2016-11-01

To investigate the relationship between trainee doctors' attachment style and their performance in qualifying clinical and communication skills assessments. Participants were 190 undergraduate medical students whose performance was assessed by examiners across two areas (communication and clinical skills) during their qualifying Objective Structured Clinical Examination (OSCE). Simulated patients also rated communication skills. Participants' attachment style was rated across two dimensions, avoidance and anxiety, using the Relationship Questionnaire (RQ). Lower levels of attachment avoidance and anxiety significantly predicted higher performance in both communication and clinical skills. Trainee doctors' attachment styles are associated with patient communication and clinical performance. Further research is needed to investigate the impact of attachment on consultations between doctors and patients within clinical settings. Attachment theory can inform our understanding why, for some student doctors, interacting with patients may be particularly challenging and require additional support by medical educators. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Experimental and Modeling Study on Detachment of Silver Nanoparticles in Saturated Granular Media

NASA Astrophysics Data System (ADS)

Kim, I.; Jeon, C. H.; Lawler, D. F.

2017-12-01

The detachment of citrate-capped silver nanoparticles (AgNPs) previously captured in a column packed with 350-μm glass beads was investigated either by increasing the hydrodynamic force (filtration velocity) or by reducing electrosteric attraction. Overall, the physical enforcement showed negligible (0.4 0.7%) release of attached AgNPs while the chemically-driven force resulted in the noticeable release up to 25.5% of attached AgNPs. Among the chemical parameters tested in this study, Na ionic strength reduction clearly demonstrated the reversible deposition in the secondary energy minimum of classical DLVO theory, yielding the most significant release of the attached AgNPs. The immediate and transient AgNP release after the ionic strength reduction further corroborated the weak deposition. However, an insignificant release was observed with Ca ionic strength reduction due to the strong Ca-citrate complexation and the subsequent deposition in the primary energy minimum; calculations indicated that the depth of the secondary energy minimum was only 1/10 that of the Na ion case. The natural organic matter (NOM) coating on both AgNPs and granular media resulted in approximately 6.1% greater AgNP release compared to the case without NOM coating, indicating additional weak deposition due to the reduced steric attraction between AgNPs and granular media. A modified filtration model in agreement with the experimental data provided the estimated detachment coefficient as a transient AgNP releasing capacity independent of the amount of attached AgNPs. The marginal difference between the detachment coefficients from Na ionic strength reduction and NOM coating indicates the release potential by NOM coating was possibly underestimated in the experimental study due to a lesser amount of the initially attached AgNPs. The findings provide insights into chemical factors on possible reentrainment behavior of the engineered nanoparticles in soil and groundwater contamination.
The method of attachment influences accelerometer-based activity data in dogs.

PubMed

Martin, Kyle W; Olsen, Anastasia M; Duncan, Colleen G; Duerr, Felix M

2017-02-10

Accelerometer-based activity monitoring is a promising new tool in veterinary medicine used to objectively assess activity levels in dogs. To date, it is unknown how device orientation, attachment method, and attachment of a leash to the collar holding an accelerometer affect canine activity data. It was our goal to evaluate whether attachment methods of accelerometers affect activity counts. Eight healthy, client-owned dogs were fitted with two identical neck collars to which two identical activity monitors were attached using six different methods of attachment. These methods of attachment evaluated the use of a protective case, positioning of the activity monitor and the tightness of attachment of the accelerometer. Lastly, the effect of leash attachment to the collar was evaluated. For trials where the effect of leash attachment to the collar was not being studied, the leash was attached to a harness. Activity data obtained from separate monitors within a given experiment were compared using Pearson correlation coefficients and across all experiments using the Kruskal-Wallis Test. There was excellent correlation and low variability between activity monitors on separate collars when the leash was attached to a harness, regardless of their relative positions. There was good correlation when activity monitors were placed on the same collar regardless of orientation. There were poor correlations between activity monitors in three experiments: when the leash was fastened to the collar that held an activity monitor, when one activity monitor was housed in the protective casing, and when one activity monitor was loosely zip-tied to the collar rather than threaded on using the provided metal loop. Follow-up, pair-wise comparisons identified the correlation associated with these three methods of attachment to be statistically different from the level of correlation when monitors were placed on separate collars. While accelerometer-based activity monitors are useful tools to objectively assess physical activity in dogs, care must be taken when choosing a method to attach the device. The attachment of the activity monitor to the collar should utilize a second, dedicated collar that is not used for leash attachment and the attachment method should remain consistent throughout a study period.
PubMed Central

AHADI, H.; JOMEHRI, F.; RAHGOZAR, M.

2013-01-01

Summary Objectives. Despite advances in screening and treatment during past several Decades, cervical cancer remains a major health problem for Iranian women. Recent researches have focused on factors related to development of health behavior in an effort to design effective early interventions. The current study aimed to investigate the role of attachment styles on cervix cancer screening barriers among women of BandarAbbas-Iran. Methods. In an analytic-cross sectional study, 681 women aged 21-65 referring to health centers were selected randomly and after completing written informed consents were investigated by Revised Adult Attachment Scale (RAAS) (Collins and Read), Pap smear screening barriers and demographic data questionnaire. The data were analyzed by Pearson correlation coefficient, linear regressions and chi-square test. Results. The results showed significant association between attachment styles and screening barriers. There was a negative significant relation between secure attachment style and screening barriers and there was a positive significant association between insecure attachment style (anxiety and avoidant) and screening barriers. The regression analysis indicated that insecure attachment style (avoidant) were predictors of barriers to the Pap smear screening test in this regard. There was a significant association between age and residential area and participation in Pap smear test. Conclusions. Insecure attachment style is associated with hazardous risk behaviors and these results can be useful for health service providers in preventive planning of screening and identification of people susceptible to risk and the design of the intervention. PMID:24779284
Maternal personal resources and children's socioemotional and behavioral adjustment.

PubMed

Al-Yagon, Michal

2008-09-01

The study examined the role of three maternal personal resources [sense of coherence (SOC), attachment style, and social/emotional feelings of loneliness] in explaining children's socioemotional adjustment (self-rated loneliness and SOC, and mother-rated child behavior) and children's (self-rated) secure attachment. The sample included 58 mother-child dyads (27 boys and 31 girls) aged 8-11 years. Preliminary analyses indicated significant group differences between mothers with high or low scores on the two subscales of the attachment scale (i.e., avoidance and anxiety), on their SOC, and their social/emotional loneliness. Findings revealed that maternal SOC significantly contributed to all child socioemotional adjustment measures and attachment scores. In addition, the current findings demonstrated the role of maternal anxious attachment in explaining children's externalizing behaviors. Discussion focused on the unique value of maternal characteristics for understanding social and emotional adjustment among school-age children.
Autobiographical Memory Phenomenology and Content Mediate Attachment Style and Psychological Distress

PubMed Central

Sutin, Angelina R.; Gillath, Omri

2009-01-01

In two studies, the present research tested the phenomenology and content of autobiographical memory as distinct mediators between attachment avoidance and anxiety and depressive symptoms. In Study 1, participants (N = 454) completed measures of attachment and depressive symptoms in one session, and retrieved and rated two self-defining memories of romantic relationships in a separate session. In Study 2, participants (N = 534) were primed with attachment security, attachment insecurity, or a control prime and then retrieved and rated a self-defining relationship memory. Memory phenomenology, specifically memory coherence and emotional intensity, mediated the association between attachment avoidance and depressive symptoms, whereas the negative affective content of the memory mediated the association between attachment anxiety and depressive symptoms. Priming attachment security led to retrieval of a more coherent relationship memory, whereas insecurity led to the retrieval of a more incoherent relationship memory. Discussion focuses on the construction and recollection of memories as underlying mechanisms of adult attachment and psychological distress, the importance of memory coherence, and the implications for counseling research and practice. PMID:20706555
Trajectories of Mothers' Emotional Availability: Relations with Infant Temperament in Predicting Attachment Security

PubMed Central

Kim, Bo-Ram; Chow, Sy-Miin; Bray, Bethany; Teti, Douglas M.

2017-01-01

The present study examined observations of parenting quality (mothers' emotional availability - EA) during infant bedtimes at 4 points across the infants' first year, assessing relations between levels and trajectories of emotional availability and infant attachment at 12 months and the role of infant temperament in moderating these associations. The sample (N = 128) was predominantly Euro-American (82.5%) and at low socioeconomic risk. Latent growth curve modeling with latent basis coefficients indicated substantial individual differences in initial levels and slopes in EA trajectories across the first year. Both levels of maternal EA and EA trajectories across the first year predicted 12-month infant attachment security. Although maternal EA tended to decrease across the first year in the full sample, EA trajectories that showed a “bounce-back” between 6 and 12 months, suggesting more successful maternal adaptation to an expanding infant developmental repertoire, predicted greater infant security at 12 months. In addition, linkages between latent EA trajectories and 12-month attachment were moderated by 3-month infant temperamental reactivity and regulation. These findings indicate that infant attachment security is sensitive to both static and dynamic aspects of parenting quality across the first year, and that infant temperament can interact with both in predicting infant attachment. PMID:27852132
Trajectories of mothers' emotional availability: relations with infant temperament in predicting attachment security.

PubMed

Kim, Bo-Ram; Chow, Sy-Miin; Bray, Bethany; Teti, Douglas M

2017-02-01

The present study examined observations of parenting quality (mothers' emotional availability - EA) during infant bedtimes at 4 points across the infants' first year, assessing relations between levels and trajectories of EA and infant attachment at 12 months and the role of infant temperament in moderating these associations. The sample (N = 128) was predominantly Euro-American (82.5%) and at low socioeconomic risk. Latent growth curve modeling with latent basis coefficients indicated substantial individual differences in initial levels and slopes in EA trajectories across the first year. Both levels of maternal EA and EA trajectories across the first year predicted 12-month infant attachment security. Although maternal EA tended to decrease across the first year in the full sample, EA trajectories that showed a "bounce-back" between 6 and 12 months, suggesting more successful maternal adaptation to an expanding infant developmental repertoire, predicted greater infant security at 12 months. In addition, linkages between latent EA trajectories and 12-month attachment were moderated by 3-month infant temperamental reactivity and regulation. These findings indicate that infant attachment security is sensitive to both static and dynamic aspects of parenting quality across the first year, and that infant temperament can interact with both in predicting infant attachment.
Attenuation of fluorocarbons released from foam insulation in landfills.

PubMed

Scheutz, Charlotte; Dote, Yutaka; Fredenslund, Anders M; Mosbaek, Hans; Kjeldsen, Peter

2007-11-15

Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs) have been used as blowing agents (BAs) for foam insulation in home appliances and building materials, which after the end of their useful life are disposed of in landfills. The objective of this project was to evaluate the potential for degradation of BAs in landfills, and to develop a landfill model, which could simulate the fate of BAs in landfills. The investigation was performed by use of anaerobic microcosm studies using different types of organic waste and anaerobic digested sludge as inoculum. The BAs studied were CFC-11, CFC-12, HCFC-141b, HFC-134a, and HFC-245fa. Experiments considering the fate of some of the expected degradations products of CFC-11 and CFC-12 were included like HCFC-21, HCFC-22, HCFC-31, HCFC-32, and HFC-41. Degradation of all studied CFCs and HCFCs was observed regardless the type of waste used. In general, the degradation followed first-order kinetics. CFC-11 was rapidly degraded from 590 microg L(-1) to less than 5 microg L(-1) within 15-20 days. The degradation pattern indicated a sequential production of HCFC-21, HCFC-31, and HFC-41. However, the production of degradation products did not correlate with a stoichiometric removal of CFC-11 indicating that other degradation products were produced. HCFC-21 and HCFC-31 were further degraded whereas no further degradation of HFC-41 was observed. The degradation rate coefficient was directly correlated with the number of chlorine atoms attached to the carbon. The highest degradation rate coefficient was obtained for CFC-11, whereas lower rates were seen for HCFC-21 and HCFC-31. Equivalent results were obtained for CFC-12. HCFC-141b was also degraded with rates comparable to HCFC-21 and CFC-12. Anaerobic degradation of the studied HFCs was not observed in any of the experiments within a run time of up to 200 days. The obtained degradation rate coefficients were used as input for an extended version of an existing landfill fate model incorporating a time dependent BA release from co-disposed foam insulation waste. Predictions with the model indicate that the emission of foam released BAs may be strongly attenuated by microbial degradation reactions. Sensitivity analysis suggests that there is a need for determination of degradation rates under more field realistic scenarios.
Characterizing the adhesion of motile and nonmotile Escherichia coli to a glass surface using a parallel-plate flow chamber.

PubMed

McClaine, Jennifer W; Ford, Roseanne M

2002-04-20

A parallel-plate flow chamber was used to measure the attachment and detachment rates of Escherichia coli to a glass surface at various fluid velocities. The effect of flagella on adhesion was investigated by performing experiments with several E. coli strains: AW405 (motile); HCB136 (nonmotile mutant with paralyzed flagella); and HCB137 (nonmotile mutant without flagella). We compared the total attachment rates and the fraction of bacteria retained on the surface to determine how the presence and movement of the flagella influence transport to the surface and adhesion strength in this dynamic system. At the lower fluid velocities, there was no significant difference in the total attachment rates for the three bacterial strains; nonmotile strains settled at a rate that was of the same order of magnitude as the diffusion rate of the motile strain. At the highest fluid velocity, the effect of settling was minimized to better illustrate the importance of motility, and the attachment rates of both nonmotile strains were approximately five times slower than that of the motile bacteria. Thus, different processes controlled the attachment rate depending on the parameter regime in which the experiment was performed. The fractions of motile bacteria retained on the glass surface increased with increasing velocity, whereas the opposite trend was found for the nonmotile strains. This suggests that the rotation of the flagella enables cells to detach from the surface (at the lower fluid velocities) and strengthens adhesion (at higher fluid velocities), whereas nonmotile cells detach as a result of shear. There was no significant difference in the initial attachment rates of the two nonmotile species, which suggests that merely the presence of flagella was not important in this stage of biofilm development. Copyright 2002 Wiley Periodicals, Inc.
Waste-assimilation study of Koshkonong Creek below sewage-treatment plant at Sun Prairie, Wisconsin

USGS Publications Warehouse

Grant, R. Stephen

1976-01-01

A waste-load-assimilation study of a reach of Koshkonong Creek below the Sun Prairie, Wisconsin, sewage-treatment-plant outfall indicated that a high level of treatment would be required to meet Wisconsin water-quality standards. To maintain a minimum dissolved-oxygen concentration of 5 mg/liter during the critical summer low-flow period, 5-day carbonaceous biochemical-oxygen demand in waste discharges should not exceed 5 mg/liter and ammonium nitrogen should not exceed 1.5 mg/liter. Advanced treatment with denitrification is required because stream-reaeration coefficients are not high enough to offset deoxygenation caused by an abundance of attached biological slimes. The slimes apparently consumed dissolved oxygen at a rate of about 110 mg/liter per day at the time of the stream survey. During the critical summer low-flow period, natural stream discharge is very small compared to waste-water discharge , so benefits of dilution are insignificant. An evaluation of two proposed alternative waste-water discharge sites indicated that the present discharge site is hydraulically superior to these sites. Stream-reaeration coefficients used in the study were based on measurements using the radioactive-tracer method. (Woodard-USGS)
Design of plywood and paper flywheel rotors

NASA Astrophysics Data System (ADS)

Erdman, A. G.; Hagen, D. L.; Gaff, S. A.

1982-05-01

Technical and economic design factors of cellulosic rotors are compared with conventional materials for stationary flywheel energy storage systems. Wood species, operation in a vacuum, assembly and costs of rotors are evaluated. Wound kraft paper, twine and plywood rotors are examined. Two hub attachments are designed. Support stiffness is shown to be constrained by the material strength, rotor configuration and speed ratio. Preliminary duration of load tests was performed on vacuum dried hexagonal birch plywood. Dynamic and static rotor hub fatigue equipment is designed. Moisture loss rates while vacuum drying plywood cylinders were measured, and the radial and axial diffusion coefficients were evaluated. Diffusion coefficients of epoxy coated plywood cylinders were also obtained. Economics of cellulosic and conventional rotors were examined. Plywood rotor manufacturing costs were evaluated. The optimum economic shape for laminated rotors is shown to be cylindrical. Vacuum container costs are parametrically derived and based on material properties and costs. Containment costs are significant and are included in comparisons. The optimum design stress and wound rotor configuration are calculated for seventeen examples. Plywood rotors appear to be marginally competitive with the steel hose wire or E glass rotors. High performance oriented kraft paper rotors potentially provide the lowest energy storage costs in stationary systems.
A sibling adoption study of adult attachment: The influence of shared environment on attachment states of mind

PubMed Central

Caspers, Kristin; Yucuis, Rebecca; Troutman, Beth; Arndt, Stephan; Langbehn, Douglas

2009-01-01

This study extends existing research investigating sibling concordance on attachment by examining concordance for adult attachment in a sample of 126 genetically unrelated sibling pairs. The Adult Attachment Interview (George, Kaplan, & Main, 1985; Main, Goldwyn, & Hesse, 2003) was used to assess states of mind with regard to attachment. The average age of the participants was 39 years old. The distribution of attachment classifications was independent of adoptive status. Attachment concordance rates were unassociated with gender concordance and sibling age difference. Concordance for autonomous/non-autonomous classifications was significant at 61% as was concordance for primary classifications at 53%. The concordance rate for not-unresolved/unresolved was non-significant at 67%. Our findings demonstrate similarity of working models of attachment between siblings independent of genetic relatedness between siblings and generations (i.e., parent and child). These findings extend previous research by further implicating shared environment as a major influence on sibling similarities on organized patterns of attachment in adulthood. The non-significant concordance for the unresolved classification suggests that unresolved loss or trauma may be less influenced by shared environment and more likely to be influenced by post-childhood experiences or genetic factors. PMID:18049934
Maternal Personal Resources and Children's Socioemotional and Behavioral Adjustment

ERIC Educational Resources Information Center

Al-Yagon, Michal

2008-01-01

The study examined the role of three maternal personal resources [sense of coherence (SOC), attachment style, and social/emotional feelings of loneliness] in explaining children's socioemotional adjustment (self-rated loneliness and SOC, and mother-rated child behavior) and children's (self-rated) secure attachment. The sample included 58…

Adolescents' multiple versus single primary attachment figures, reorganization of attachment hierarchy, and adjustments: the important people interview approach.

PubMed

Umemura, Tomotaka; Lacinová, Lenka; Kraus, Jakub; Horská, Eliška; Pivodová, Lenka

2018-04-20

Using 212 adolescents from a central-European country (mean age = 14.02, SD = 2.05, ranged from 11 to 18 years; females = 54%) and a multi-informant method to measure adolescents' behavioral and emotional adjustments, the present study explored three aspects regarding the attachment hierarchy. (1) The three types of behavioral systems of Rosenthal and Kobak's important people interview (IPI) were initially validated using an exploratory factor analysis with a US sample. Using a confirmatory factor analysis with a Czech sample, we replicated these three behavioral systems: attachment bond, support seeking, and affiliation. (2) We found that adolescents who developed attachment bond to multiple primary attachment figures were likely to score lower on both teacher-rated and parent-rated internalizing problems compared to those who had a single primary attachment figure. These multiple primary attachment figures tended to be family members (not peers). (3) Early adolescents who placed parents low in their attachment hierarchy scored higher on self-reported negative affect and lower on self-reported positive affect compared to early adolescents who placed parents high. The present study highlights multiple (vs. single) primary attachment figures as a protective factor and the premature reorganization of attachment hierarchy as a risk factor for adolescents' emotional and affective adjustments.
STAG2 promotes error correction in mitosis by regulating kinetochore-microtubule attachments.

PubMed

Kleyman, Marianna; Kabeche, Lilian; Compton, Duane A

2014-10-01

Mutations in the STAG2 gene are present in ∼20% of tumors from different tissues of origin. STAG2 encodes a subunit of the cohesin complex, and tumors with loss-of-function mutations are usually aneuploid and display elevated frequencies of lagging chromosomes during anaphase. Lagging chromosomes are a hallmark of chromosomal instability (CIN) arising from persistent errors in kinetochore-microtubule (kMT) attachment. To determine whether the loss of STAG2 increases the rate of formation of kMT attachment errors or decreases the rate of their correction, we examined mitosis in STAG2-deficient cells. STAG2 depletion does not impair bipolar spindle formation or delay mitotic progression. Instead, loss of STAG2 permits excessive centromere stretch along with hyperstabilization of kMT attachments. STAG2-deficient cells display mislocalization of Bub1 kinase, Bub3 and the chromosome passenger complex. Importantly, strategically destabilizing kMT attachments in tumor cells harboring STAG2 mutations by overexpression of the microtubule-destabilizing enzymes MCAK (also known as KIF2C) and Kif2B decreased the rate of lagging chromosomes and reduced the rate of chromosome missegregation. These data demonstrate that STAG2 promotes the correction of kMT attachment errors to ensure faithful chromosome segregation during mitosis. © 2014. Published by The Company of Biologists Ltd.
Therapists' and clients' ratings of real relationship, attachment, therapist self-disclosure, and treatment progress.

PubMed

Fuertes, Jairo N; Moore, Michael; Ganley, Jennifer

2018-01-20

While there has been much research on the role of the working alliance in psychotherapy, researchers only recently began investigating the role of the real relationship in treatment. In the current study on therapist and client dyads, we used actor-partner interdependence modeling (APIM) to examine associations between therapists' and clients' ratings of the real relationship, therapist self-disclosure, attachment, and treatment progress. APIM analyses allowed for an examination into how therapists' and clients' views of a particular phenomenon might affect their own ratings (actor), as well as the others' (partner) ratings of that same phenomenon. Significant negative associations between therapist self-reported attachment anxiety and avoidance and therapist-rated real relationship and treatment progress. Significant positive associations were found between client-rated real relationship and client-rated treatment progress. These results and others are discussed in the context of the literature along with implications for future research in this area. Clinical or methodological significance of this article: The current study has uncovered evidence that therapists' ratings of their attachment anxiety and avoidance are negatively and significantly associated with their ratings of the real relationship and of treatment progress. The results also indicate that both therapists' and clients' ratings of the real relationship were positively and significantly associated with their ratings of clients' treatment progress.
Photometry of occultation candidate stars. I - Uranus 1985 and Saturn 1985-1991

NASA Technical Reports Server (NTRS)

French, L. M.; Morales, G.; Dalton, A. S.; Klavetter, J. J.; Conner, S. R.

1985-01-01

Photometric observations of five stars to be occulted by the rings around Uranus are presented. The four stars to be occulted by Saturn or its rings during the period 1985-1991 were also observed. The observations were carried out with a CCD detector attached to the Kitt Peak McGraw-Hill 1.30-m telescope. Landolt standards of widely ranging V-I color indices were used to determine the extinction coefficients, transformation coefficients, and zero points of the stars. Mean extinction coefficients are given for each night of observation. K magnitudes for each star were estimated on the basis of the results of Johnson (1967). The complete photometric data set is given in a series of tables.
Developing a scale to measure "attachment to the local community" in late middle aged individuals.

PubMed

Sakai, Taichi; Omori, Junko; Takahashi, Kazuko; Mitsumori, Yasuko; Kobayashi, Maasa; Ono, Wakanako; Miyazaki, Toshie; Anzai, Hitomi; Saito, Mika

2016-01-01

Objectives This study was conducted to develop a scale for measuring "attachment to the local community" for its use in health services. The scale is also intended to nurture new social relationships in late middle-aged individuals.Methods Thirty items were initially planned to be included in the scale to measure "attachment to the local community", according to a previous study that identified the concept. The study subjects were late middle-aged residents of City B in Prefecture A, located in Tokyo suburbs. From the basic resident register data, 1,000 individuals (local residents in the 50-69 year age group) were selected by a multi-stage random sampling technique, on the basis of their residential area, age, and sex (while maintaining the male to female ratio). An unsigned self-administered questionnaire was distributed to the subjects, and the responses were collected by postal mail. The collected data was analyzed using psychometric study of scale.Results Valid responses were obtained from 583 subjects, and the response rate was 58.3%. In an item analysis, none of the items were rejected. In a subsequent factor analysis, 7 items were eliminated. These items included 2 items with a factor loading of <0.40, 3 items loading on multiple factors and showing a factor loading of ≥0.40, and 2 items with a low factor correlation (0.04-0.16). These items included factors that related to only these 2 items. Consequently, 23 items in the following 4-factor structure were selected as the scale items: "Source of vitality to live life," "Intention to cherish ties with people," "Place where one can be oneself," and "Pride of being a resident." Cronbach's coefficient α for the entire scale of "attachment to the local community" was 0.95, demonstrating internal consistency. We then examined the correlation with an existing scale to measure social support; the results revealed a statistically significant correlation and confirmed criterion-related validity (P<0.001). In addition, the fit indices in a covariance structure analysis showed adequate values.Conclusions The developed scale was considered reliable and appropriate for measuring "attachment to the local community."
Exopolysaccharides from lactic acid bacteria as corrosion inhibitors

NASA Astrophysics Data System (ADS)

Ignatova-Ivanova, Tsveteslava; Ivanov, Radoslav

2016-03-01

Bacterial EPSs (exopolysaccharides) are believed to play an important role in the environment by promoting survival strategies such as bacterial attachment to surfaces and nutrient trapping, which facilitate processes of biofilm formation and development. These microbial biofilms have been implicated in corrosion of metals, bacterial attachment to prosthetic devices, fouling of heat exchange surfaces, toxicant immobilization, and fouling of ship hulls. In this paper, data on EPS production and the effect of EPS on corrosion of steel produced by Lactobacillus sp. are presented and discussed. Lactobacillus delbrueckii K27, Lactobacillus delbrueckii B8, Lactobacillus delbrueckii KO43, Lactobacillus delbrueckii K3, Lactobacillus delbrueckii K15 and Lactobacillus delbrueckii K17 was obtained from Collection of Department of General and Applied Microbiology, Sofia University. It was tested for its ability to produce exopolysaccharides when cultivated in a media containing 10% sucrose, 10% lacose and 10% maltose. The study of the corrosive stability of steel samples was conducted on the gravimetrique method. The rate of corrosion, the degree of protection, and coefficient of protection have been calculated. The structure of layer over steel plates was analysed by SEM (scanning electron microscopy) JSM 5510. It could be underlined that 10% sucrose, 10% lactose and 10% maltose in the media stimulated the process of protection of corrosion.
Parent characteristics linked with daughters' attachment styles.

PubMed

Kilmann, Peter R; Vendemia, Jennifer M C; Parnell, Michele M; Urbaniak, Geoffrey C

2009-01-01

This study investigated links between parent characteristics and daughters' attachment styles for 90 female undergraduates and their married biological parents. Parents with a secure attachment pattern were rated as more accepting, less controlling, more competent, and more consistent in showing love and affection to their daughter in contrast to parents with an insecure attachment pattern. Significant positive associations were found between mothers' fearful attachment scores and the fearful, preoccupied, and dismissive attachment scores of daughters. Daughters of matched secure parents were more likely to report a secure attachment style, while daughters of matched insecure parents were more likely to report an insecure attachment style.
The Role of Adult Attachment Style in Forgiveness Following an Interpersonal Offense

ERIC Educational Resources Information Center

Lawler-Row, Kathleen A.; Younger, Jarred W.; Piferi, Rachel L.; Jones, Warren H.

2006-01-01

The role of attachment style in relation to forgiveness was investigated in 2 betrayal interviews. Blood pressure and heart rate were assessed, along with attachment style, forgiveness, empathy, and emotional expressiveness. Securely attached individuals were more forgiving of the specific offense, had higher levels of trait forgiveness, and…
Do Adolescents and Parents Reconstruct Memories about Their Conflict as a Function of Adolescent Attachment?

PubMed Central

Dykas, Matthew J.; Woodhouse, Susan S.; Ehrlich, Katherine B.; Cassidy, Jude

2010-01-01

This study examined whether 17-year-old adolescents (n = 189) and their parents reconstruct their memory for an adolescent-parent laboratory conflict over a 6-week period as a function of adolescent (AAI) attachment organization. It also compared participants’ perceptions of conflict over time to observational ratings of the conflict to further characterize the nature of the attachment-related memory biases that emerged. Secure adolescents reconstructed interactions with each parent more favorably over time, whereas insecure adolescents showed less favorable reconstructive memory. Likewise, mothers of secure girls reconstructed conflicts more favorably over time, whereas mothers of insecure boys showed less favorable reconstructive memory. Participant ratings were associated with observational ratings in theoretically consistent ways. Contrary to expectations, fathers showed no attachment-related memory biases. PMID:20840233
Temperature dependency of virus and nanoparticle transport and retention in saturated porous media

NASA Astrophysics Data System (ADS)

Sasidharan, Salini; Torkzaban, Saeed; Bradford, Scott A.; Cook, Peter G.; Gupta, Vadakattu V. S. R.

2017-01-01

The influence of temperature on virus (PRD1 and ΦX174) and carboxyl-modified latex nanoparticle (50 and 100 nm) attachment was examined in sand-packed columns under various physiochemical conditions. When the solution ionic strength (IS) equaled 10 and 30 mM, the attachment rate coefficient (katt) increased up to 109% (p < 0.0002) and the percentage of the sand surface area that contributed to attachment (Sf) increased up to 160% (p < 0.002) when the temperature was increased from 4 to 20 °C. Temperature effects at IS = 10 and 30 mM were also dependent on the system hydrodynamics; i.e., enhanced retention at a lower pore water velocity (0.1 m/day). Conversely, this same temperature increase had a negligible influence on katt and Sf values when IS was 1 mM or > 50 mM. An explanation for these observations was obtained from extended interaction energy calculations that considered nanoscale roughness and chemical heterogeneity on the sand surface. Interaction energy calculations demonstrated that the energy barrier to attachment in the primary minimum (ΔΦa) decreased with increasing IS, chemical heterogeneity, and temperature, especially in the presence of small amounts of nanoscale roughness (e.g., roughness fraction of 0.05 and height of 20 nm in the zone of influence). Temperature had a negligible effect on katt and Sf when the IS = 1 mM because of the large energy barrier, and at IS = 50 mM because of the absence of an energy barrier. Conversely, temperature had a large influence on katt and Sf when the IS was 10 and 30 mM because of the presence of a small ΔΦa on sand with nanoscale roughness and a chemical (positive zeta potential) heterogeneity. This has large implications for setting parameters for the accurate modeling and transport prediction of virus and nanoparticle contaminants in ground water systems.
Variable pleiotropic effects from mutations at the same locus hamper prediction of fitness from a fitness component.

PubMed

Pepin, Kim M; Samuel, Melanie A; Wichman, Holly A

2006-04-01

The relationship of genotype, fitness components, and fitness can be complicated by genetic effects such as pleiotropy and epistasis and by heterogeneous environments. However, because it is often difficult to measure genotype and fitness directly, fitness components are commonly used to estimate fitness without regard to genetic architecture. The small bacteriophage X174 enables direct evaluation of genetic and environmental effects on fitness components and fitness. We used 15 mutants to study mutation effects on attachment rate and fitness in six hosts. The mutants differed from our lab strain of X174 by only one or two amino acids in the major capsid protein (gpF, sites 101 and 102). The sites are variable in natural and experimentally evolved X174 populations and affect phage attachment rate. Within the limits of detection of our assays, all mutations were neutral or deleterious relative to the wild type; 11 mutants had decreased host range. While fitness was predictable from attachment rate in most cases, 3 mutants had rapid attachment but low fitness on most hosts. Thus, some mutations had a pleiotropic effect on a fitness component other than attachment rate. In addition, on one host most mutants had high attachment rate but decreased fitness, suggesting that pleiotropic effects also depended on host. The data highlight that even in this simple, well-characterized system, prediction of fitness from a fitness component depends on genetic architecture and environment.
Cellular instability in rapid directional solidification - Bifurcation theory

NASA Technical Reports Server (NTRS)

Braun, R. J.; Davis, S. H.

1992-01-01

Merchant and Davis performed a linear stability analysis on a model for the directional solidification of a dilute binary alloy valid for all speeds. The analysis revealed that nonequilibrium segregation effects modify the Mullins and Sekerka cellular mode, whereas attachment kinetics has no effect on these cells. In this paper, the nonlinear stability of the steady cellular mode is analyzed. A Landau equation is obtained that determines the amplitude of the cells. The Landau coefficient here depends on both nonequilibrium segregation effects and attachment kinetics. This equation gives the ranges of parameters for subcritical bifurcation (jump transition) or supercritical bifurcation (smooth transition) to cells.
Apparatus and method to reduce wear and friction between CMC-to-metal attachment and interface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cairo, Ronald Ralph; Parolini, Jason Robert; Delvaux, John McConnell

An apparatus to reduce wear and friction between CMC-to-metal attachment and interface, including a metal layer configured for insertion between a surface interface between a CMC component and a metal component. The surface interface of the metal layer is compliant relative to asperities of the surface interface of the CMC component. A coefficient of friction between the surface interface of the CMC component and the metal component is about 1.0 or less at an operating temperature between about 300.degree. C. to about 325.degree. C. and a limiting temperature of the metal component.
The relationship between vulnerable attachment style, psychopathology, drug abuse, and retention in treatment among methadone maintenance treatment patients.

PubMed

Potik, David; Peles, Einat; Abramsohn, Yahli; Adelson, Miriam; Schreiber, Shaul

2014-01-01

The relationship between vulnerable attachment style, psychopathology, drug abuse, and retention in treatment among patients in methadone maintenance treatment (MMT) was examined by the Vulnerable Attachment Style Questionnaire (VASQ), the Symptom Checklist-90 (SCL-90), and drug abuse urine tests. After six years, retention in treatment and repeated urine test results were studied. Patients with vulnerable attachment style (a high VASQ score) had higher rates of drug abuse and higher psychopathology levels compared to patients with secure attachment style, especially on the interpersonal sensitivity, anxiety, hostility, phobic anxiety, and paranoid ideation scales. Drug abstinence at baseline was related to retention in treatment and to higher rates of drug abstinence after six years in MMT, whereas a vulnerable attachment style could not predict drug abstinence and retention in treatment. Clinical Implications concerning treatment of drug abusing populations and methodological issues concerning the VASQ's subscales are also discussed.
Attachment and physiological reactivity to infant crying in young adulthood: dissociation between experiential and physiological arousal in insecure adoptees.

PubMed

Schoenmaker, Christie; Huffmeijer, Renske; van IJzendoorn, Marinus H; Bakermans-Kranenburg, Marian J; van den Dries, Linda; Linting, Mariëlle; van der Voort, Anja; Juffer, Femmie

2015-02-01

The associations between attachment representations of adopted young adults and their experiential and physiological arousal to infant crying were examined. Attachment representations were assessed with the Attachment Script Assessment (ASA), and the young adults listened to infant cries, during which ratings of cry perception were collected and physiological reactivity was measured. Secure adoptees showed a well-integrated response to infant distress: heart-rate increases and respiratory sinus arrhythmia (RSA) withdrawal were coupled with heightened perception of urgency in these individuals. In insecure adoptees RSA withdrawal was absent, and a combination of lowered perceived urgency and heightened sympathetic arousal was found, reflecting a deactivating style of emotional reactivity. Overall, our findings support the idea that internal working models of attachment explain individual differences in the way attachment-related information is processed. Copyright © 2014 Elsevier Inc. All rights reserved.
A meta-analysis of longitudinal associations between substance use and interpersonal attachment security.

PubMed

Fairbairn, Catharine E; Briley, Daniel A; Kang, Dahyeon; Fraley, R Chris; Hankin, Benjamin L; Ariss, Talia

2018-05-01

Substance use has long been associated with close relationship distress. Although the direction of influence for this association has not been established, it has often been assumed that substance use is the causal agent and that close relationship distress is the effect. But research seeking to establish temporal precedence in this link has produced mixed findings. Further, theoretical models of substance use and close relationship processes present the plausibility of the inverse pathway-that insecure close relationships may serve as a vulnerability factor for the development of later substance problems. The current review applies an attachment-theoretical framework to the association between close social bonds and substance use and substance-related problems. Targeting longitudinal studies of attachment and substance use, we examined 665 effect sizes drawn from 34 samples (total N = 56,721) spanning time frames ranging from 1 month to 20 years (M = 3.8 years). Results revealed a significant prospective correlation between earlier attachment and later substance use (r = -.11, 95% CI [-.14, -0.08]). Further, cross-lagged coefficients were calculated which parsed auto-regressive effects, indicating that lower attachment security temporally preceded increases in substance use (r = -.05, 95% CI [-.06, -.04]). Analyses further indicated that the pathway from earlier attachment to later substance use was significantly stronger than that from earlier substance use to later attachment. Results also revealed several moderators of the attachment-substance use link. These findings suggest that insecure attachment may be a vulnerability factor for substance use, and indicate close relationship quality as a promising line of inquiry in research on substance use disorder risk. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
A Meta-Analysis of Longitudinal Associations between Substance Use and Interpersonal Attachment Security

PubMed Central

Fairbairn, Catharine E.; Briley, Daniel A.; Kang, Dahyeon; Fraley, R. Chris; Hankin, Benjamin L.; Ariss, Talia

2018-01-01

Substance use has long been associated with close relationship distress. While the direction of influence for this association has not been established, it has often been assumed that substance use is the causal agent and that close relationship distress is the effect. But research seeking to establish temporal precedence in this link has produced mixed findings. Further, theoretical models of substance use and close relationship processes present the plausibility of the inverse pathway—that insecure close relationships may serve as a vulnerability factor for the development of later substance problems. The current review applies an attachment-theoretical framework to the association between close social bonds and substance use and substance-related problems. Targeting longitudinal studies of attachment and substance use, we examined 665 effect sizes drawn from 34 samples (total N=56,721) spanning time frames ranging from 1 month to 20 years (M=3.8 years). Results revealed a significant prospective correlation between earlier attachment and later substance use (r =−.11, 95%CI=−.14 to −0.08). Further, cross-lagged coefficients were calculated which parsed auto-regressive effects, indicating that lower attachment security temporally preceded increases in substance use (r=−.05, 95%CI=−.06 to −.04). Analyses further indicated that the pathway from earlier attachment to later substance use was significantly stronger than that from earlier substance use to later attachment. Results also revealed several moderators of the attachment-substance use link. These findings suggest that insecure attachment may be a vulnerability factor for substance use, and indicate close relationship quality as a promising line of inquiry in research on substance use disorder risk. PMID:29494194
Electron Attachment to Radicals and Highly-Excited States in Laser-Irradiated CCl_2F_2*

NASA Astrophysics Data System (ADS)

Pinnaduwage, Lal; Datskos, Panos

1997-10-01

We have measured electron attachment rate constants for two species produced via ArF-excimer- laser irradiated CF_2Cl_2, i.e., the CF_2Cl radical and the highly-excited electronically-excited states of CF_2Cl_2. These measurements show that while electron attachment to the fragment radical has a rate constants about an order of magnitude higher compared to the ground states of CF_2Cl_2, electron attachment to the highly- excited states have many orders of magnitude larger rate constants. To our knowledge, only one other electron attachment measurement has been conducted on molecular fragments up to now. Implications of these measurements for plasma processing discharges will be discussed. Research supported by the National Science Foundation under contract No. ECS-9626217 with the University of Tennessee, Knoxville. The Oak Ridge National Laboratory is managed by Lockheed Martin Energy Research Corp. for the U. S. DOE under contract No. DE-AC05- 96OR22464.
Laboratory assessment of the mobility of water-dispersed engineered nanoparticles in a red soil (Ultisol)

NASA Astrophysics Data System (ADS)

Wang, Dengjun; Su, Chunming; Zhang, Wei; Hao, Xiuzhen; Cang, Long; Wang, Yujun; Zhou, Dongmei

2014-11-01

Soils are major sinks of engineered nanoparticles (ENPs) as results of land applications of sewage sludge, accidental spills, or deliberate applications of ENPs (e.g., nano-pesticides). In this study, the transport behaviors of four widely used ENPs (i.e., titanium dioxide [TiO2], buckminsterfullerene [C60], single-walled carbon nanotube [SWNT], and elemental silver [Ag0]) were investigated in water-saturated columns packed with either a quartz sand, a red soil (Ultisol), or sand/soil mixtures with soil mass fraction (λ) from 0% to 100% at slightly acidic solution pH (4.0-5.0). The mobility of tested ENPs decreased significantly with increasing λ, which was attributed to increased surface area and/or retention sites imparted by iron oxides, clay minerals, and organic matter in the red soil. Breakthrough curves of all ENPs exhibited blocking effects (decreasing deposition rate over time) and were well-described using an unfavorable and favorable, two-site kinetic attachment model accounting for random sequential adsorption on the favorable site. Modeled maximum retention capacity and first-order attachment rate coefficient on the favorable site both increased linearly with increasing λ, suggesting that transport parameters of ENPs in natural soils may be accurately extrapolated from transport parameters in the sand/soil mixtures. In addition, the mobility of three negatively charged ENPs (C60, SWNT, and Ag0 NPs) was reversely correlated with their average hydrodynamic diameters, highlighting that the average hydrodynamic diameter of negatively charged ENPs is the dominant physicochemical characteristics controlling their mobility in the Ultisol.
Observational attachment theory-based parenting measures predict children's attachment narratives independently from social learning theory-based measures.

PubMed

Matias, Carla; O'Connor, Thomas G; Futh, Annabel; Scott, Stephen

2014-01-01

Conceptually and methodologically distinct models exist for assessing quality of parent-child relationships, but few studies contrast competing models or assess their overlap in predicting developmental outcomes. Using observational methodology, the current study examined the distinctiveness of attachment theory-based and social learning theory-based measures of parenting in predicting two key measures of child adjustment: security of attachment narratives and social acceptance in peer nominations. A total of 113 5-6-year-old children from ethnically diverse families participated. Parent-child relationships were rated using standard paradigms. Measures derived from attachment theory included sensitive responding and mutuality; measures derived from social learning theory included positive attending, directives, and criticism. Child outcomes were independently-rated attachment narrative representations and peer nominations. Results indicated that Attachment theory-based and Social Learning theory-based measures were modestly correlated; nonetheless, parent-child mutuality predicted secure child attachment narratives independently of social learning theory-based measures; in contrast, criticism predicted peer-nominated fighting independently of attachment theory-based measures. In young children, there is some evidence that attachment theory-based measures may be particularly predictive of attachment narratives; however, no single model of measuring parent-child relationships is likely to best predict multiple developmental outcomes. Assessment in research and applied settings may benefit from integration of different theoretical and methodological paradigms.

An analytical design procedure for the determination of effective leading edge extensions on thick delta wings

NASA Technical Reports Server (NTRS)

Ghaffari, F.; Chaturvedi, S. K.

1984-01-01

An analytical design procedure for leading edge extensions (LEE) was developed for thick delta wings. This LEE device is designed to be mounted to a wing along the pseudo-stagnation stream surface associated with the attached flow design lift coefficient of greater than zero. The intended purpose of this device is to improve the aerodynamic performance of high subsonic and low supersonic aircraft at incidences above that of attached flow design lift coefficient, by using a vortex system emanating along the leading edges of the device. The low pressure associated with these vortices would act on the LEE upper surface and the forward facing area at the wing leading edges, providing an additional lift and effective leading edge thrust recovery. The first application of this technique was to a thick, round edged, twisted and cambered wing of approximately triangular planform having a sweep of 58 deg and aspect ratio of 2.30. The panel aerodynamics and vortex lattice method with suction analogy computer codes were employed to determine the pseudo-stagnation stream surface and an optimized LEE planform shape.
Computation of electron transport and relaxation properties in gases based on improved multi-term approximation of Boltzmann equation

NASA Astrophysics Data System (ADS)

Cai, X. J.; Wang, X. X.; Zou, X. B.; Lu, Z. W.

2018-01-01

An understanding of electron kinetics is of importance in various applications of low temperature plasmas. We employ a series of model and real gases to investigate electron transport and relaxation properties based on improved multi-term approximation of the Boltzmann equation. First, a comparison of different methods to calculate the interaction integrals has been carried out; the effects of free parameters, such as vmax, lmax, and the arbitrary temperature Tb, on the convergence of electron transport coefficients are analyzed. Then, the modified attachment model of Ness et al. and SF6 are considered to investigate the effect of attachment on the electron transport properties. The deficiency of the pulsed Townsend technique to measure the electron transport and reaction coefficients in electronegative gases is highlighted when the reduced electric field is small. In order to investigate the effect of external magnetic field on the electron transport properties, Ar plasmas in high power impulse sputtering devices are considered. In the end, the electron relaxation properties of the Reid model under the influence of electric and magnetic fields are demonstrated.
Spectator motives and points of attachment: an investigation on professional basketball.

PubMed

Gencer, R Timucin; Kiremitci, Olcay; Boyacioglu, Hayal

2011-12-01

Spectator attendance to professional basketball in Turkey is significantly less than desired. Keeping in mind how important spectators are for team sports, understanding factors that affect game attendance will offer essential clues in terms of increasing spectator attendance. The main purpose of this study was to determine the relationships between basketball spectators' motives and points of attachment. With consideration to this purpose, the present study has tested the validity and reliability of the Motivation Scale for Sport Consumption and the Points of Attachment Index for Turkish basketball spectators. 197 basketball spectators participated in the study. Confirmatory factor analysis results demonstrated that the original models of the measurement tools employed for the study showed an acceptable degree of fit with the data. The internal consistency coefficients of the scales were found to be between 0.59 and 0.80 for the Motivation Scale for Sport Consumption and between 0.53 and 0.88 for the Points of Attachment Index. The canonical correlation analysis only returned a single significant function. The motives aesthetics and escape stood out in terms of the significant function, while the sport type (basketball in this study) stood out in the sense of attachment. Relationships identified between basketball spectators' motives and points of attachment could help sports managers and marketing experts to develop strategies focusing on increasing spectator attendance to their teams' games.
Spectator Motives and Points of Attachment: an Investigation on Professional Basketball

PubMed Central

Gencer, R. Timucin; Kiremitci, Olcay; Boyacioglu, Hayal

2011-01-01

Spectator attendance to professional basketball in Turkey is significantly less than desired. Keeping in mind how important spectators are for team sports, understanding factors that affect game attendance will offer essential clues in terms of increasing spectator attendance. The main purpose of this study was to determine the relationships between basketball spectators’ motives and points of attachment. With consideration to this purpose, the present study has tested the validity and reliability of the Motivation Scale for Sport Consumption and the Points of Attachment Index for Turkish basketball spectators. 197 basketball spectators participated in the study. Confirmatory factor analysis results demonstrated that the original models of the measurement tools employed for the study showed an acceptable degree of fit with the data. The internal consistency coefficients of the scales were found to be between 0.59 and 0.80 for the Motivation Scale for Sport Consumption and between 0.53 and 0.88 for the Points of Attachment Index. The canonical correlation analysis only returned a single significant function. The motives aesthetics and escape stood out in terms of the significant function, while the sport type (basketball in this study) stood out in the sense of attachment. Relationships identified between basketball spectators’ motives and points of attachment could help sports managers and marketing experts to develop strategies focusing on increasing spectator attendance to their teams’ games. PMID:23487414
Reduction of Fe(III) colloids by Shewanella putrefaciens: A kinetic model

NASA Astrophysics Data System (ADS)

Bonneville, Steeve; Behrends, Thilo; van Cappellen, Philippe; Hyacinthe, Christelle; Röling, Wilfred F. M.

2006-12-01

A kinetic model for the microbial reduction of Fe(III) oxyhydroxide colloids in the presence of excess electron donor is presented. The model assumes a two-step mechanism: (1) attachment of Fe(III) colloids to the cell surface and (2) reduction of Fe(III) centers at the surface of attached colloids. The validity of the model is tested using Shewanella putrefaciens and nanohematite as model dissimilatory iron reducing bacteria and Fe(III) colloidal particles, respectively. Attachment of nanohematite to the bacteria is formally described by a Langmuir isotherm. Initial iron reduction rates are shown to correlate linearly with the relative coverage of the cell surface by nanohematite particles, hence supporting a direct electron transfer from membrane-bound reductases to mineral particles attached to the cells. Using internally consistent parameter values for the maximum attachment capacity of Fe(III) colloids to the cells, Mmax, the attachment constant, KP, and the first-order Fe(III) reduction rate constant, k, the model reproduces the initial reduction rates of a variety of fine-grained Fe(III) oxyhydroxides by S. putrefaciens. The model explains the observed dependency of the apparent Fe(III) half-saturation constant, Km∗, on the solid to cell ratio, and it predicts that initial iron reduction rates exhibit saturation with respect to both the cell density and the abundance of the Fe(III) oxyhydroxide substrate.
TECHNICAL NOTE: Actuation displacement performance change of pre-stressed piezoelectric actuators attached to a flat surface

NASA Astrophysics Data System (ADS)

Goo, Nam Seo; Phuoc Phan, Van; Park, Hoon Cheol

2009-03-01

Pre-stressed piezoelectric actuators such as RAINBOW, THUNDER™, and LIPCA have a curvature due to a mismatch of the coefficient of thermal expansion, which inevitably exists during the manufacturing process. This technical note provides an answer to the question of how their actuation displacement performance changes when the curved pre-stressed piezoelectric actuators are attached to a flat surface. Finite element analysis with the ANSYS™ program was used to calculate the stress distribution inside a LIPCA, one of the pre-stressed piezoelectric actuators, after the LIPCA was cured and attached to the flat surface. The change of actuation displacement performance can be explained in terms of the relation between the piezoelectric strain constants and internal stress. As a result of the curing and attachment to a flat surface, the two-dimensional stress state inside the piezoceramic layer leads to an expected increase of around 51% for the longitudinal piezoelectric strain constant. To confirm this result, we reconsider the experimental results of the actuation moment measurement of the LIPCA and bare lead zirconium titanate.
75 FR 45174 - New Postal Product

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-02

...-published Rates, rate schedules, a management analysis, and certification that prices satisfy applicable pricing criteria. Attachment 3 is a Statement of Justification by the Executive Director, Global Business Management. Attachment 4 is a representative agreement between the Postal Service and a customer of GEPS--Non...
The Development of the Cleft Aesthetic Rating Scale: A New Rating Scale for the Assessment of Nasolabial Appearance in Complete Unilateral Cleft Lip and Palate Patients.

PubMed

Mosmuller, David G M; Mennes, Lisette M; Prahl, Charlotte; Kramer, Gem J C; Disse, Melissa A; van Couwelaar, Gijs M; Niessen, Frank B; Griot, J P W Don

2017-09-01

The development of the Cleft Aesthetic Rating Scale, a simple and reliable photographic reference scale for the assessment of nasolabial appearance in complete unilateral cleft lip and palate patients. A blind retrospective analysis of photographs of cleft lip and palate patients was performed with this new rating scale. VU Medical Center Amsterdam and the Academic Center for Dentistry of Amsterdam. Complete unilateral cleft lip and palate patients at the age of 6 years. Photographs that showed the highest interobserver agreement in earlier assessments were selected for the photographic reference scale. Rules were attached to the rating scale to provide a guideline for the assessment and improve interobserver reliability. Cropped photographs revealing only the nasolabial area were assessed by six observers using this new Cleft Aesthetic Rating Scale in two different sessions. Photographs of 62 children (6 years of age, 44 boys and 18 girls) were assessed. The interobserver reliability for the nose and lip together was 0.62, obtained with the intraclass correlation coefficient. To measure the internal consistency, a Cronbach alpha of .91 was calculated. The estimated reliability for three observers was .84, obtained with the Spearman Brown formula. A new, easy to use, and reliable scoring system with a photographic reference scale is presented in this study.
Equilibrium muscle cross-bridge behavior. Theoretical considerations.

PubMed Central

Schoenberg, M

1985-01-01

We have developed a model for the equilibrium attachment and detachment of myosin cross-bridges to actin that takes into account the possibility that a given cross-bridge can bind to one of a number of actin monomers, as seems likely, rather than to a site on only a single actin monomer, as is often assumed. The behavior of this multiple site model in response to constant velocity, as well as instantaneous stretches, was studied and the influence of system parameters on the force response explored. It was found that in the multiple site model the detachment rate constant has considerably greater influence on the mechanical response than the attachment rate constant. It is shown that one can obtain information about the detachment rate constants either by examining the relationship between the apparent stiffness and duration of stretch for constant velocity stretches or by examining the force-decay rate constants following an instantaneous stretch. The main effect of the attachment rate constant is to scale the mechanical response by influencing the number of attached cross-bridges. The significance of the modeling for the interpretation of experimental results is discussed. PMID:4041539
Maternal state of mind regarding attachment, maternal depression and children's family drawings in the early school years.

PubMed

Fihrer, Irene; McMahon, Cathy

2009-11-01

The current study explored how children's family drawings in the early school years might be related to their exposure to recurrent episodes of maternal depression. We also examined prospectively relations among maternal state of mind regarding attachment derived from the Adult Attachment Interview and earlier mother-child attachment from the Strange Situation Procedure (both measured when the child was 12-15 months old) and later family drawings. Seventy-five mothers were assessed for symptoms of depression periodically between birth and child age 6-8 years. At this age, children completed a family drawing rated using an attachment-based scoring system. Both mothers' state of mind regarding attachment and their overall depression were modestly, but significantly, correlated with a global rating of the child's drawings. When both predictors were considered together, however, neither was significant, reflecting collinearity between the two variables. In this study, women with a non-autonomous state of mind regarding attachment were significantly more likely to experience recurrent depression. The earlier classification of the child's attachment to the mother from the Strange Situation Procedure was not related to the family drawing.
Testing Maternal Depression and Attachment Style as Moderators of Early Head Start's Effects on Parenting

PubMed Central

Berlin, Lisa J.; Whiteside-Mansell, Leanne; Roggman, Lori A.; Green, Beth L.; Robinson, JoAnn; Spieker, Susan

2010-01-01

This study examined maternal depression, attachment avoidance, and attachment anxiety as moderators of Early Head Start's effects on four parenting outcomes assessed at age 3. Participants (N = 947) were drawn from six sites of the Early Head Start National Research and Evaluation Project, a multi-site randomized trial. Findings suggest more positive program effects for mothers with less initial attachment avoidance or attachment anxiety. First, baseline attachment avoidance moderated EHS program effects on observed maternal supportiveness, such that program mothers with lower baseline attachment avoidance were rated as more supportive of their 3-year-olds than program mothers with higher baseline attachment avoidance. Second, program effects on spanking varied depending on mothers’ baseline attachment anxiety. PMID:21240694
Testing maternal depression and attachment style as moderators of Early Head Start's effects on parenting.

PubMed

Berlin, Lisa J; Whiteside-Mansell, Leanne; Roggman, Lori A; Green, Beth L; Robinson, JoAnn; Spieker, Susan

2011-01-01

This study examined maternal depression, attachment avoidance, and attachment anxiety as moderators of Early Head Start's effects on four parenting outcomes assessed at age three. Participants (N = 947) were drawn from six sites of the Early Head Start National Research and Evaluation Project, a multi-site randomized trial. Findings suggest more positive program effects for mothers with less initial attachment avoidance or attachment anxiety. First, baseline attachment avoidance moderated Early Head Start program effects on observed maternal supportiveness, such that program mothers with lower baseline attachment avoidance were rated as more supportive of their three-year-olds than program mothers with higher baseline attachment avoidance. Second, program effects on spanking varied depending on mothers' baseline attachment anxiety.
Langley Full-scale-tunnel Investigation of Maximum Lift and Stability Characteristics of an Airplane Having Approximately Triangular Plan Form (DM-1 Glider)

NASA Technical Reports Server (NTRS)

Lovell, J Calvin; Wilson, Herbert A JR

1947-01-01

An investigation of the DM-1 Glider, which had approximately triangular plan form, an aspect ratio of 1.8 and a 60 degree sweptback leading edge, has been conducted in the Langley full-scale tunnel. The investigation consisted of the determination of the separate effects of the following modifications made to the glider on its maximum lift and stability characteristics: (a) installation of sharp leading edges over the inboard semispan of the wing, (b) removal of the vertical fin, (c) sealing of the elevon control-balance slots, (d) installation of redesigned thin vertical surfaces, (e) installation of faired sharp leading edges, and (f) installation of canopy. The maximum lift coefficient of the DM-1 glider was increased from 0.61 to 1.01 by the installation of semispan sharp leading edges, and from 1.01 to 1.24 by the removal of the vertical fin and sealing of the elevon control-balance slots. The highest maximum lift coefficient (1.32) was obtained when the faired sharp leading edges and the thin vertical surfaces were attached to the glider. The original DM-1 glider was longitudinally stable. The semispan sharp leading edges shifted the neutral point forward approximately 3 percent of the root chord at moderate lift coefficients, and the glider configuration with these sharp leading edges attached was longitudinally unstable, for the assumed center-of-gravity location, at lift coefficients above 0.73. Sealing the elevon control-balance slots and installing the faired sharp leading edges, the thin vertical surfaces, and the canopy shifted the neutral point forward approximately 8 percent of the root chord.
Association between childhood maltreatment and adult emotional dysregulation in a low-income, urban, African American sample: moderation by oxytocin receptor gene.

PubMed

Bradley, Bekh; Westen, Drew; Mercer, Kristina B; Binder, Elisabeth B; Jovanovic, Tanja; Crain, Daniel; Wingo, Aliza; Heim, Christine

2011-05-01

The ability to effectively regulate emotions and a secure attachment style are critical for maintaining mental health across the life span. The experience of childhood maltreatment interferes with normal development of emotional regulation and dramatically increases risk for a wide range of psychiatric disorders in adulthood. The central nervous system oxytocin systems are critically involved in mediating social attachment and buffering psychophysiological responses to stress. We therefore investigated the impact of childhood maltreatment and an oxytocin receptor (OXTR) single nucleotide polymorphism (rs53576) and their interaction on emotional dysregulation and attachment style in adulthood in a sample of low-income, African American men and women recruited from primary care clinics of an urban, public hospital. Consistent with prior research, we found that the severity of childhood maltreatment was associated with increased levels of emotional dysregulation in adulthood. Childhood maltreatment was also positively associated with ratings of disorganized/unresolved adult attachment style and negatively associated with ratings of secure adult attachment style. There was no direct association between rs53576 and emotional dysregulation or ratings of adult attachment style. However, there were significant interactions between rs53576 and childhood maltreatment in predicting level of adult emotional dysregulation and attachment style. Specifically, G/G genotype carriers were at risk for increased emotional dysregulation when exposed to three or more categories of childhood abuse. In addition, G/G genotype carriers exhibited enhanced disorganized adult attachment style when exposed to severe childhood abuse compared to A/A and A/G carriers. Our findings suggest that A allele carriers of OXTR rs53576 are resilient against the effects of severe childhood adversity, by protection against emotional dysregulation and disorganized attachment.
Psychological functioning and predictors of father-infant relationship in IVF fathers and controls.

PubMed

Hjelmstedt, Anna; Collins, Aila

2008-03-01

The psychological functioning of fathers with children born after in vitro fertilization (IVF) has received little attention. Among men in general, little is known about predictors of early father-infant relationship (here also defined as attachment). The first aim was to compare IVF fathers and control fathers regarding personality traits, state anxiety, depressive symptoms and early father-infant attachment. The second aim was to assess whether early father-infant relationship is explained by the father's prenatal relationship with the unborn infant, his personality traits, state anxiety and symptoms of depression. Fifty-three IVF fathers and 36 controls filled in self-rating scales measuring father-infant attachment, personality, anxiety and symptoms of depression at 2 months postpartum. At gestational week 26 their prenatal relationship to the unborn infant was assessed. It was found that IVF fathers rated more somatic and psychic anxiety, indirect aggression and less assertiveness. They were as strongly attached to their infant as the controls. Fathers, who had rated higher attachment to their unborn infant during pregnancy, who were less anxious, more assertive and less irritable, were more attached to their infants than men who had been less attached to their unborn infants and who were more anxious, less assertive and more irritable. In conclusion, although IVF fathers are as strongly attached to their infants as other fathers, they may benefit from emotional support as they have elevated levels of anxiety proneness and indirect aggression. It is important to pay attention during pregnancy to fathers who have a less optimal attachment to their unborn infant and who have high levels of anxiety and irritability, as those three factors are related to a weak emotional father-infant relationship.
Association between childhood maltreatment and adult emotional dysregulation in a low-income, urban, African American sample: Moderation by oxytocin receptor gene

PubMed Central

BRADLEY, BEKH; WESTEN, DREW; MERCER, KRISTINA B.; BINDER, ELISABETH B.; JOVANOVIC, TANJA; CRAIN, DANIEL; WINGO, ALIZA; HEIM, CHRISTINE

2015-01-01

The ability to effectively regulate emotions and a secure attachment style are critical for maintaining mental health across the life span. The experience of childhood maltreatment interferes with normal development of emotional regulation and dramatically increases risk for a wide range of psychiatric disorders in adulthood. The central nervous system oxytocin systems are critically involved in mediating social attachment and buffering psychophysiological responses to stress. We therefore investigated the impact of childhood maltreatment and an oxytocin receptor (OXTR) single nucleotide polymorphism (rs53576) and their interaction on emotional dysregulation and attachment style in adulthood in a sample of low-income, African American men and women recruited from primary care clinics of an urban, public hospital. Consistent with prior research, we found that the severity of childhood maltreatment was associated with increased levels of emotional dysregulation in adulthood. Childhood maltreatment was also positively associated with ratings of disorganized/unresolved adult attachment style and negatively associated with ratings of secure adult attachment style. There was no direct association between rs53576 and emotional dysregulation or ratings of adult attachment style. However, there were significant interactions between rs53576 and childhood maltreatment in predicting level of adult emotional dysregulation and attachment style. Specifically, G/G genotype carriers were at risk for increased emotional dysregulation when exposed to three or more categories of childhood abuse. In addition, G/G genotype carriers exhibited enhanced disorganized adult attachment style when exposed to severe childhood abuse compared to A/A and A/G carriers. Our findings suggest that A allele carriers of OXTR rs53576 are resilient against the effects of severe childhood adversity, by protection against emotional dysregulation and disorganized attachment. PMID:23786688
IV INTERNATIONAL CONFERENCE ON ATOM AND MOLECULAR PULSED LASERS (AMPL'99): Discharge characteristics in a nonchain HF(DF) laser

NASA Astrophysics Data System (ADS)

Apollonov, V. V.; Kazantsev, S. Yu; Saifulin, A. V.; Firsov, K. N.

2000-06-01

It is found that for SF6—hydrocarbon (deuterocarbon) mixtures having a composition typical for nonchain HF(DF) lasers, the electric field strength reduced to the partial pressure of SF6 (pSF6) in the quasistationary phase of a volume self-sustained discharge (E/pSF6)st=92 V m-1 Pa-1 is close to the known critical value (E/p)cr=89 V m-1 Pa-1, which is specified by the condition that the electron-impact ionisation rate of SF6 is equal to the rate of electron attachment to SF6 molecules. This testifies to the decisive role of these two processes and allows the use of the known approximations of the effective ionisation coefficient and the electron drift velocity for pure SF6 when calculating the discharge characteristics. The oscilloscope traces of voltage and current calculated in this approximation for lasers with apertures ranging from 4 to 27 cm deviated from the experimental data by no more than 10%.
Development and validation of PediaTrac™: A web-based tool to track developing infants.

PubMed

Lajiness-O'Neill, Renée; Brooks, Judith; Lukomski, Angela; Schilling, Stephen; Huth-Bocks, Alissa; Warschausky, Seth; Flores, Ana-Mercedes; Swick, Casey; Nyman, Tristin; Andersen, Tiffany; Morris, Natalie; Schmitt, Thomas A; Bell-Smith, Jennifer; Moir, Barbara; Hodges, Elise K; Lyddy, James E

2018-02-01

PediaTrac™, a 363-item web-based tool to track infant development, administered in modules of ∼40-items per sampling period, newborn (NB), 2--, 4--, 6--, 9-- and 12--months was validated. Caregivers answered demographic, medical, and environmental questions, and questions covering the sensorimotor, feeding/eating, sleep, speech/language, cognition, social-emotional, and attachment domains. Expert Panel Reviews and Cognitive Interviews (CI) were conducted to validate the item bank. Classical Test Theory (CTT) and Item Response Theory (IRT) methods were employed to examine the dimensionality and psychometric properties of PediaTrac with pooled longitudinal and cross-sectional cohorts (N = 132). Intraclass correlation coefficients (ICC) for the Expert Panel Review revealed moderate agreement at 6 -months and good reliability at other sampling periods. ICC estimates for CI revealed moderate reliability regarding clarity of the items at NB and 4 months, good reliability at 2--, 9-- and 12--months and excellent reliability at 6 -months. CTT revealed good coefficient alpha estimates (α ≥ 0.77 for five of the six ages) for the Social-Emotional/Communication, Attachment (α ≥ 0.89 for all ages), and Sensorimotor (α ≥ 0.75 at 6-months) domains, revealing the need for better targeting of sensorimotor items. IRT modeling revealed good reliability (r = 0.85-0.95) for three distinct domains (Feeding/Eating, Social-Emotional/Communication and Attachment) and four subdomains (Feeding Breast/Formula, Feeding Solid Food, Social-Emotional Information Processing, Communication/Cognition). Convergent and discriminant construct validity were demonstrated between our IRT-modeled domains and constructs derived from existing developmental, behavioral and caregiver measures. Our Attachment domain was significantly correlated with existing measures at the NB and 2-month periods, while the Social-Emotional/Communication domain was highly correlated with similar constructs at the 6-, 9- and 12-month periods. PediaTrac has potential for producing novel and effective estimates of infant development via the Sensorimotor, Feeding/Eating, Social-Emotional/Communication and Attachment domains. Copyright © 2018 Elsevier Inc. All rights reserved.
[PAH Cations as Viable Carriers of DIBs

NASA Technical Reports Server (NTRS)

Snow, Ted

1998-01-01

This report is intended to fill in the blanks in NASA's file system for our lab astro study of molecular ions of astrophysical interest. In order to give NASA what it needs for its files, I attach below the text of the section from our recent proposal to continue this work, in which we describe progress to date, including a large number of publications. Our initial studies were focused on PAH cations, which appear to be viable candidates as the carriers of the DIBs, an idea that has been supported by laboratory spectroscopy of PAH cations in inert matrices. Beginning with the simplest aromatic (benzene; C6H6) and moving progressively to larger species (naphthalene, C10OH8; pyrene, C16H10; and most recently chrysene, C18H12), we have been able to derive rate coefficients for reactions with neutral spices that are abundant in the diffuse interstellar medium.
Development of a composite geodetic structure for space construction, phase 1A

NASA Technical Reports Server (NTRS)

1980-01-01

The development of a geodetic beam and beam builder for on orbit construction of large truss type space structures is discussed. The geodetic beam is a lightweight, open lattice structure composed of an equilateral gridwork of crisscrossing rods. The beam provides a high degree of stiffness and minimizes structural distortion, due to temperature gradients, through the incorporation of a new graphite and glass reinforced thermoplastic composite material with a low coefficient of thermal expansion. A low power consuming, high production rate, beam builder automatically fabricates the geodetic beams in space using rods preprocessed on Earth. Three areas of the development are focused upon; (1) geodetic beam designs for local attachment of equipment or beam to beam joining in a parallel or crossing configurations, (2) evaluation of long life pultruded rods capable of service temperatures higher than possible with the HMS/P1700 rod material, and (3) evalaution of high temperature joint encapsulant materials.

METHES: A Monte Carlo collision code for the simulation of electron transport in low temperature plasmas

NASA Astrophysics Data System (ADS)

Rabie, M.; Franck, C. M.

2016-06-01

We present a freely available MATLAB code for the simulation of electron transport in arbitrary gas mixtures in the presence of uniform electric fields. For steady-state electron transport, the program provides the transport coefficients, reaction rates and the electron energy distribution function. The program uses established Monte Carlo techniques and is compatible with the electron scattering cross section files from the open-access Plasma Data Exchange Project LXCat. The code is written in object-oriented design, allowing the tracing and visualization of the spatiotemporal evolution of electron swarms and the temporal development of the mean energy and the electron number due to attachment and/or ionization processes. We benchmark our code with well-known model gases as well as the real gases argon, N2, O2, CF4, SF6 and mixtures of N2 and O2.
Transport of viruses through saturated and unsaturated columns packed with sand

USGS Publications Warehouse

Anders, R.; Chrysikopoulos, C.V.

2009-01-01

Laboratory-scale virus transport experiments were conducted in columns packed with sand under saturated and unsaturated conditions. The viruses employed were the male-specific RNA coliphage, MS2, and the Salmonella typhimurium phage, PRD1. The mathematical model developed by Sim and Chrysikopoulos (Water Resour Res 36:173-179, 2000) that accounts for processes responsible for removal of viruses during vertical transport in one-dimensional, unsaturated porous media was used to fit the data collected from the laboratory experiments. The liquid to liquid-solid and liquid to air-liquid interface mass transfer rate coefficients were shown to increase for both bacteriophage as saturation levels were reduced. The experimental results indicate that even for unfavorable attachment conditions within a sand column (e.g., phosphate-buffered saline solution; pH = 7.5; ionic strength = 2 mM), saturation levels can affect virus transport through porous media. ?? Springer Science+Business Media B.V. 2008.
Triggering Excimer Lasers by Photoionization from Corona Discharges

NASA Astrophysics Data System (ADS)

Xiong, Zhongmin; Duffey, Thomas; Brown, Daniel; Kushner, Mark

2009-10-01

High repetition rate ArF (192 nm) excimer lasers are used for photolithography sources in microelectronics fabrication. In highly attaching gas mixtures, preionization is critical to obtaining stable, reproducible glow discharges. Photoionization from a separate corona discharge is one technique for preionization which triggers the subsequent electron avalanche between the main electrodes. Photoionization triggering of an ArF excimer laser sustained in multi-atmosphere Ne/Ar/F2/Xe gas mixtures has been investigated using a 2-dimensional plasma hydrodynamics model including radiation transport. Continuity equations for charged and neutral species, and Poisson's equation are solved coincident with the electron temperature with transport coefficients obtained from solutions of Boltzmann's equation. Photoionizing radiation is produced by a surface discharge which propagates along a corona-bar located adjacent to the discharge electrodes. The consequences of pulse power waveform, corona bar location, capacitance and gas mixture on uniformity, symmetry and gain of the avalanche discharge will be discussed.
The relationship between adult attachment style and therapeutic alliance in individual psychotherapy: a meta-analytic review.

PubMed

Diener, Marc J; Monroe, Joel M

2011-09-01

The present study examined the relationship between adult attachment style and therapeutic alliance in individual psychotherapy. Search procedures yielded 17 independent samples (total N = 886, average n = 52, standard deviation = 24) for inclusion in the meta-analysis. Results indicated that greater attachment security was associated with stronger therapeutic alliances, whereas greater attachment insecurity was associated with weaker therapeutic alliances, with an overall weighted effect size of r = .17, p < .001 (95% confidence interval = .10-.23). Publication bias analyses did not indicate any cause for concern regarding the results. The data were not demonstrably heterogeneous (Q = 6.10, df = 16, p = .99), and all between-study moderator analyses were nonsignificant (p values > .10) with the exception of the source of alliance ratings; results indicated that patient-rated alliance demonstrated a significantly larger relationship with attachment compared with therapist-rated alliance (Qbetween = 3.95, df = 1, p = .047). Implications for clinical practice and future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved). (c) 2011 APA, all rights reserved.
Do adolescents and parents reconstruct memories about their conflict as a function of adolescent attachment?

PubMed

Dykas, Matthew J; Woodhouse, Susan S; Ehrlich, Katherine B; Cassidy, Jude

2010-01-01

This study examined whether 17-year-old adolescents (n=189) and their parents reconstructed their memory for an adolescent-parent laboratory conflict over a 6-week period as a function of adolescent attachment organization. It also compared participants' perceptions of conflict over time to observational ratings of the conflict to further characterize the nature of the attachment-related memory biases that emerged. Secure adolescents reconstructed interactions with each parent more favorably over time, whereas insecure adolescents showed less favorable reconstructive memory. Likewise, mothers of secure girls reconstructed conflicts more favorably over time, whereas mothers of insecure boys showed less favorable reconstructive memory. Participant ratings were associated with observational ratings in theoretically consistent ways. Contrary to expectations, fathers showed no attachment-related memory biases. © 2010 The Authors. Child Development © 2010 Society for Research in Child Development, Inc.
Relation between premorbid personality and patterns of emotion expression in mid- to late-stage dementia.

PubMed

Magai, C; Cohen, C I; Culver, C; Gomberg, D; Malatesta, C

1997-11-01

Twenty-seven nursing home patients with mid- to late-stage dementia participated in a study of the relation between preillness personality, as indexed by attachment and emotion regulation style, and current emotional behavior. Preillness measures were completed by family members and current assessments of emotion were supplied by nursing home aides and family members; in addition, emotion was coded during a family visit using an objective coding system for facial emotion expressions. Attachment style was found to be related to the expression of positive affect, with securely attached individuals displaying more positive affect than avoidantly attached individuals. In addition, high ratings on premorbid hostility were associated with higher rates of negative affect and lower rates of positive affect. These findings indicate that premorbid aspects of personality show continuity over time, even in mid- to late-stage dementia.
Attachment Style, Perceived Loneliness, and Psychological Well-Being in Smoking and Non-Smoking University Students.

PubMed

Habibi, Mojtaba; Hosseini, Farhad; Darharaj, Mohammad; Moghadamzadeh, Ali; Radfar, Farhad; Ghaffari, Yasaman

2018-05-19

The growing rate of smoking cigarettes among the youths necessitates examining its contributing factors. Accordingly, we aimed to compare smoking and nonsmoking university students in their attachment styles, perceived loneliness, and psychological well-being. To this end, we recruited 100 current smokers and 100 nonsmoking students by using a convenience sampling method from Shahid Beheshti University, Tehran, Iran. All participants completed the Adult Attachment Scale, Loneliness Scale, and General Health Questionnaire. Data analysis indicated that compared to nonsmokers, smokers had a more anxious attachment style and they felt lonelier. Moreover, current results showed that smokers suffered from higher rates of psychological problems than nonsmokers. These results suggest that smoking is influenced by a set of psychological factors and therefore, prevention and treatment programs targeting these factors may be effective in reducing the rate of smoking cigarettes among university students.
Dissociative Attachment Reactions of Electrons with Gas Phase Superacids

NASA Astrophysics Data System (ADS)

Liu, Xifan

Using the flowing afterglow Langmuir probe (FALP) technique, dissociative attachment coefficients beta for reactions of electrons with gas phase superacids HCo(PF_3)_4, HRh(PF _3)_4 and carbonyl hydride complexes HMn(CO)_5, HRe(CO) _5 have been determined under thermal conditions over the approximate temperature range 300~ 550 K. The superacids react relatively slowly (< 1/20 of beta_{rm max}) with free electrons in a thermal plasma, and the values of beta obtained this far do not show a correlation between acidity and beta. The pioneer researchers in this field had speculated that any superacid would be a rapid attacher of electrons; we found that this speculation is not true in general. The product distribution of electron attachment reaction to HCo(PF_3)_4 was found to be independent of temperature even though the beta (HCo(PF_3)_4 ) increases with temperature. This leads us to propose that the electron attachment process occurs well before the excited complex dissociates. In addition, the activation energy of HCo(PF_3)_4 for electron attachment has been derived from the Arrhenius plots. The carbonyl hydride complexes, HMn(CO) _5 and HRe(CO)_5, react relatively rapidly (>1/4 of beta_{rm max}) with free electrons in thermal plasma. This indicates that these reactions cannot be significantly endothermic. Observation of rapid attachment for these non-superacids shows that the Mn-CO and Re-CO bonds are weaker than the Mn-H and Re-H bonds, respectively. Comparisons between the carbonyl and trifluorophosphine cases implies that fast electron capture is related more to the CO ligand than to the transition -metal species.
The Development of the Concept of Object as Related to Infant-Mother Attachment

ERIC Educational Resources Information Center

Bell, Silvia M.

1970-01-01

Results indicate that (1) babies have better concept of person than object as permanent, but there are important individual differences, (2) rate of person permanence development is related to infant-mother attachment, and (3) rate of person permanence development affects object permanence development. (MH)
Electron attachment to C{sub 2} fluorocarbon radicals at high temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shuman, Nicholas S.; Miller, Thomas M.; Viggiano, Albert A., E-mail: afrl.rvborgmailbox@kirtland.af.mil

Thermal electron attachment to the radical species C{sub 2}F{sub 3} and C{sub 2}F{sub 5} has been studied over the temperature range 300–890 K using the Variable Electron and Neutral Density Attachment Mass Spectrometry technique. Both radicals exclusively undergo dissociative attachment to yield F{sup −}. The rate constant for C{sub 2}F{sub 5} shows little dependence over the temperature range, remaining ∼4 × 10{sup −9} cm{sup 3} s{sup −1}. The rate constant for C{sub 2}F{sub 3} attachment rises steeply with temperature from 3 × 10{sup −11} cm{sup 3} s{sup −1} at 300 K to 1 × 10{sup −9} cm{sup 3} s{sup −1} at 890 K.more » The behaviors of both species at high temperature are in agreement with extrapolations previously made from data below 600 K using a recently developed kinetic modeling approach. Measurements were also made on C{sub 2}F{sub 3}Br and C{sub 2}F{sub 5}Br (used in this work as precursors to the radicals) over the same temperature range, and, for C{sub 2}F{sub 5}Br as a function of electron temperature. The attachment rate constants to both species rise with temperature following Arrhenius behavior. The attachment rate constant to C{sub 2}F{sub 5}Br falls with increasing electron temperature, in agreement with the kinetic modeling. The current data fall in line with past predictions of the kinetic modeling approach, again showing the utility of this simplified approach.« less
[Comparative study of three bonding methods in attaching removable thermoplastic appliances].

PubMed

Chu, Kejia; Wang, Haihui; Zheng, Zhijun; Li, Qi

2015-10-01

To evaluate the operation time and clinical effect of three types of materials (i.e., total-etching adhesive, self-etching adhesive, resin-modified glass ionomer cement) that are used to bond removable thermoplastic appliances. Thirty malocclusion patients (156 attachments) with removable thermoplastic appliances were randomly divided into three groups, with 10 individuals each. Attachments of groups A and B were bonded using 3M Adper Single Bond 2 and 3M Adper Easy One, respectively; both adhesives utilized 3M Z350 nano composite resin. Attachments of group C was directly bonded using GC Fuji Ortho LC. The operation time of each attachment was recorded. Failure rates of adhesion were evaluated during adhesion, 1 month after treatment, and 6 months after treatment. The operation time of group C was shorter than those of groups A and B (P<0.01). Significant difference of adhesion failure rates was not found among the three groups (P>0.05). No significant difference of adhesion failure rates was also observed in different times of the same group (P>0.05). The attachment stability of the three types of materials achieved satisfactory effects. However, the operation method of resin-modified glass ionomer cement is more concise and suitable for clinical promotion.
The degree-related clustering coefficient and its application to link prediction

NASA Astrophysics Data System (ADS)

Liu, Yangyang; Zhao, Chengli; Wang, Xiaojie; Huang, Qiangjuan; Zhang, Xue; Yi, Dongyun

2016-07-01

Link prediction plays a significant role in explaining the evolution of networks. However it is still a challenging problem that has been addressed only with topological information in recent years. Based on the belief that network nodes with a great number of common neighbors are more likely to be connected, many similarity indices have achieved considerable accuracy and efficiency. Motivated by the natural assumption that the effect of missing links on the estimation of a node's clustering ability could be related to node degree, in this paper, we propose a degree-related clustering coefficient index to quantify the clustering ability of nodes. Unlike the classical clustering coefficient, our new coefficient is highly robust when the observed bias of links is considered. Furthermore, we propose a degree-related clustering ability path (DCP) index, which applies the proposed coefficient to the link prediction problem. Experiments on 12 real-world networks show that our proposed method is highly accurate and robust compared with four common-neighbor-based similarity indices (Common Neighbors(CN), Adamic-Adar(AA), Resource Allocation(RA), and Preferential Attachment(PA)), and the recently introduced clustering ability (CA) index.
Searching for Global Descriptors of Engineered Nanomaterial Fate and Transport in the Environment

PubMed Central

Nowack, Bernd

2012-01-01

CONSPECTUS Engineered nanomaterials (ENMs) are a new class of environmental pollutants. Researchers are beginning to debate whether new modeling paradigms and experimental tests to obtain model parameters are required for ENMs or if approaches for existing pollutants are robust enough to predict ENM distribution between environmental compartments. This Account outlines how experimental research can yield quantitative data for use in ENM fate and exposure models. We first review experimental testing approaches that are employed with ENMs. Then we compare and contrast ENMs against other pollutants. Finally, we summarize the findings and identify research needs that may yield global descriptors for ENMs that are suitable for use in fate and transport modeling. Over the past decade, researchers have made significant progress in understanding factors that influence the fate and transport of ENMs. In some cases researchers have developed approaches toward global descriptor models (experimental, conceptual, and quantitative). We suggest the following global descriptors for ENMs: octanol-water partition coefficients, solid-water partition coefficients, attachment coefficients, and rate constants describing reactions such as dissolution, sedimentation, and degradation. ENMs appear to accumulate at the octanol-water interface and readily interact with other interfaces, such as lipid-water interfaces. Batch experiments to investigate factors that influence retention of ENMs on solid phases are very promising. However ENMs probably do not behave in the same way as dissolved chemicals, and therefore researchers need to use measurement techniques and concepts more commonly associated with colloids. Despite several years of research with ENMs in column studies, available summaries tend to discuss the effects of ionic strength, pH, organic matter, ENM type, packing media, or other parameters qualitatively rather than reporting quantitative values, such as attachment efficiencies, that would facilitate comparison across studies. Only a few structure-activity relationships have been developed for ENMs so far, but such evaluations will facilitate the understanding of the reactivities of different forms of a single ENM. The establishment of predictive capabilities for ENMs in the environment would enable accurate exposure assessments that would assist in ENM risk management. Such information is also critical for understanding the ultimate disposition of ENMs and may provide a framework for improved engineering of nanomaterials that are more environmentally benign. PMID:22950943
The RhoA-ROCK-PTEN pathway as a molecular switch for anchorage dependent cell behavior.

PubMed

Yang, Seungwon; Kim, Hyun-Man

2012-04-01

The proliferation of anchorage-dependent cells of mesenchymal origin requires the attachment of the cells to substrates. Thus, cells that are poorly attached to substrates exhibit retarded cell cycle progression or apoptotic death. A major disadvantage of most polymers used in tissue engineering is their hydrophobicity; hydrophobic surfaces do not allow cells to attach firmly and, therefore, do not allow normal proliferation rates. In this study, we investigated the molecular mechanism underlying the reduced proliferation rate of cells that are poorly attached to substrates. There was an inverse relationship between the activity of the small GTPase RhoA (RhoA) and the cell proliferation rate. RhoA activity correlated inversely with the strength of cell adhesion to the substrates. The high RhoA activity in the cells poorly attached to substrates caused an increase in the activity of Rho-associated kinase (ROCK), a well-known effector of RhoA that upregulated the activity of phosphatase and tensin homolog (PTEN). The resulting activated PTEN downregulated Akt activity, which is essential for cell proliferation. Thus, the cells that were poorly attached to substrates showed low levels of cell proliferation because the RhoA-ROCK-PTEN pathway was hyperactive. In addition, RhoA activity seemed to be related to focal adhesion kinase (FAK) activity. Weak FAK activity in these poorly attached cells failed to downregulate the high RhoA activity that restrained cell proliferation. Interestingly, reducing the expression of any component of the RhoA-ROCK-PTEN pathway rescued the proliferation rate without physico-chemical surface modifications. Based on these results, we suggest that the RhoA-ROCK-PTEN pathway acts as a molecular switch to control cell proliferation and determine anchorage dependence. In cells that are poorly attached to substrates, its inhibition is sufficient to restore cell proliferation without the need for physico-chemical modification of the material surface. Copyright © 2012 Elsevier Ltd. All rights reserved.
Italian translation and cross-cultural comparison with the Childhood Attachment and Relational Trauma Screen (CARTS).

PubMed

Simonelli, A; Sacchi, C; Cantoni, L; Brown, M; Frewen, P

2017-01-01

Background : The Childhood Attachment and Relational Trauma Screen (CARTS) is a computer-administered survey designed to assess retrospectively the socio-ecological context in which instances of child abuse may have occurred. To date, studies supporting the validity of the CARTS have only been undertaken in English-speaking North American populations. Validation projects in other countries and cross-cultural comparisons are therefore warranted. Objective : Develop and preliminarily evaluate the psychometric properties of an Italian version of the CARTS on college students and compare such observations to data acquired from Canadian students. Method : Seventy-nine undergraduate students from the University of Padua (Italy) completed an Italian translation of the CARTS as well as measures of childhood experiences, mental health and attachment, responses to which were compared to those obtained in 288 Canadian students who completed the CARTS in English. Results : Internal consistency and convergent validity with the Childhood Trauma Questionnaire and Parental Bonding Instrument were found to be acceptable for the Italian translation. Within the Italian sample, correlation analyses suggested that CARTS Mother ratings referring to attachment and abuse were associated with romantic attachment, whereas CARTS Father ratings were significantly correlated to PTSD symptoms and other symptoms of psychopathology-distress. Significant differences between Italian and Canadian students across the relationship types for the CARTS abuse and attachment scales were found, indicating that Italian students rated their mothers and fathers as simultaneously less abusive, but also less as a source of secure attachment. Conclusions : The results of this preliminary study seem to suggest convergent validity of the Italian CARTS and the association between childhood attachment-related experiences and romantic attachment. Cultural variations were identified between Canadian and Italian students in both attachment and abuse scales. Future studies to investigate cross-cultural variations in the relational context of childhood abuse and in order to boost Italian CARTS psychometric features are warranted.
Italian translation and cross-cultural comparison with the Childhood Attachment and Relational Trauma Screen (CARTS)

PubMed Central

Simonelli, A.; Sacchi, C.; Cantoni, L.; Brown, M.; Frewen, P.

2017-01-01

ABSTRACT Background: The Childhood Attachment and Relational Trauma Screen (CARTS) is a computer-administered survey designed to assess retrospectively the socio-ecological context in which instances of child abuse may have occurred. To date, studies supporting the validity of the CARTS have only been undertaken in English-speaking North American populations. Validation projects in other countries and cross-cultural comparisons are therefore warranted. Objective: Develop and preliminarily evaluate the psychometric properties of an Italian version of the CARTS on college students and compare such observations to data acquired from Canadian students. Method: Seventy-nine undergraduate students from the University of Padua (Italy) completed an Italian translation of the CARTS as well as measures of childhood experiences, mental health and attachment, responses to which were compared to those obtained in 288 Canadian students who completed the CARTS in English. Results: Internal consistency and convergent validity with the Childhood Trauma Questionnaire and Parental Bonding Instrument were found to be acceptable for the Italian translation. Within the Italian sample, correlation analyses suggested that CARTS Mother ratings referring to attachment and abuse were associated with romantic attachment, whereas CARTS Father ratings were significantly correlated to PTSD symptoms and other symptoms of psychopathology-distress. Significant differences between Italian and Canadian students across the relationship types for the CARTS abuse and attachment scales were found, indicating that Italian students rated their mothers and fathers as simultaneously less abusive, but also less as a source of secure attachment. Conclusions: The results of this preliminary study seem to suggest convergent validity of the Italian CARTS and the association between childhood attachment-related experiences and romantic attachment. Cultural variations were identified between Canadian and Italian students in both attachment and abuse scales. Future studies to investigate cross-cultural variations in the relational context of childhood abuse and in order to boost Italian CARTS psychometric features are warranted. PMID:29163857
Self-Normalized Photoacoustic Technique for the Quantitative Analysis of Paper Pigments

NASA Astrophysics Data System (ADS)

Balderas-López, J. A.; Gómez y Gómez, Y. M.; Bautista-Ramírez, M. E.; Pescador-Rojas, J. A.; Martínez-Pérez, L.; Lomelí-Mejía, P. A.

2018-03-01

A self-normalized photoacoustic technique was applied for quantitative analysis of pigments embedded in solids. Paper samples (filter paper, Whatman No. 1), attached with the pigment: Direct Fast Turquoise Blue GL, were used for this study. This pigment is a blue dye commonly used in industry to dye paper and other fabrics. The optical absorption coefficient, at a wavelength of 660 nm, was measured for this pigment at various concentrations in the paper substrate. It was shown that Beer-Lambert model for light absorption applies well for pigments in solid substrates and optical absorption coefficients as large as 220 cm^{-1} can be measured with this photoacoustic technique.
An analysis method for multi-component airfoils in separated flow

NASA Technical Reports Server (NTRS)

Rao, B. M.; Duorak, F. A.; Maskew, B.

1980-01-01

The multi-component airfoil program (Langley-MCARF) for attached flow is modified to accept the free vortex sheet separation-flow model program (Analytical Methods, Inc.-CLMAX). The viscous effects are incorporated into the calculation by representing the boundary layer displacement thickness with an appropriate source distribution. The separation flow model incorporated into MCARF was applied to single component airfoils. Calculated pressure distributions for angles of attack up to the stall are in close agreement with experimental measurements. Even at higher angles of attack beyond the stall, correct trends of separation, decrease in lift coefficients, and increase in pitching moment coefficients are predicted.
Attachment, Development, and Mental Health in Abused and Neglected Preschool Children in Foster Care: A Meta-Analysis.

PubMed

Vasileva, Mira; Petermann, Franz

2016-09-22

A proper preparation for foster parents to care for abused and neglected children includes effective training and initial diagnostics in order to plan individual treatment. Hence, a basic knowledge about the main psychosocial and developmental problems associated with abuse and neglect and their prevalence in foster children is needed. For this purpose, a systematical literature review and a series of meta-analyses were conducted. A total of 25 studies reporting data on development (n = 4,033), mental health (n = 726), and attachment (n = 255) of foster children in preschool age met the inclusion criteria. The meta-analyses indicated prevalence rates of approximately 40% for developmental, mental health problems, and insecure attachment. Rates of disorganized attachment were estimated to 22%. These findings outline the necessity of an initial trauma-oriented diagnostics and trainings for foster parents that address foster children's development, mental health, and disorganized attachment. © The Author(s) 2016.
Influence of carbon steel grade on the initial attachment of bacteria and microbiologically influenced corrosion.

PubMed

Javed, M A; Neil, W C; Stoddart, P R; Wade, S A

2016-01-01

The influence of the composition and microstructure of different carbon steel grades on the initial attachment (≤ 60 min) of Escherichia coli and subsequent longer term (28 days) corrosion was investigated. The initial bacterial attachment increased with time on all grades of carbon steel. However, the rate and magnitude of bacterial attachment varied on the different steel grades and was significantly less on the steels with a higher pearlite phase content. The observed variations in the number of bacterial cells attached across different steel grades were significantly reduced by applying a fixed potential to the steel samples. Longer term immersion studies showed similar levels of biofilm formation on the surface of the different grades of carbon steel. The measured corrosion rates were significantly higher in biotic conditions compared to abiotic conditions and were found to be positively correlated with the pearlite phase content of the different grades of carbon steel coupons.

Rate of germination and growth of in vitro produced Pasteuria spp. parasitizing Rotylenchulus reniformis

USDA-ARS?s Scientific Manuscript database

Reniform nematodes (Rotylenchulus reniformis) from pot culture were attached with in vitro produced Pasteuria spp. spores using a centrifuge attachment technique that resulted in 40-50% of the vermiform nematodes with spores adhering to their cuticles. Attached nematodes were placed into small plast...
Design, fabrication and spin testing of ceramic blade metal disk attachment

NASA Technical Reports Server (NTRS)

Calvert, G.

1979-01-01

A ceramic turbine blade-metal disk attachment was designed for small, non man-rated turbine engine applications. The selected design consisted of a hot pressed silicon nitride blade having a skewed dovetail attachment with a compliant interlayer between the disk and the blade. Two-dimensional and three-dimensional analyses predicted that life goals could be achieved, considering both NDE limitations and crack growth rates for the ceramic material. Twenty ceramic blades were fabricated to closely-held manufacturing tolerances. New fracture mechanics data at elevated temperature are presented.
Study of mother-infant attachment patterns and influence factors in Shanghai.

PubMed

Ding, Yan-hua; Xu, Xiu; Wang, Zheng-yan; Li, Hui-rong; Wang, Wei-ping

2012-05-01

In contrast to the considerable volume of international research on infant attachment development, significantly less research has been conducted in China. The present study was designed to identify the patterns of mother-infant attachment in Shanghai and to explore the influence factors. The subjects included 160 healthy infant-mother dyads. Infant attachment and temperament were assessed with the Strange Situation Procedure and Carey's temperament questionnaire, respectively; the mother's personality, maternal sensitivity and marital satisfaction were assessed with Eysenck's personality questionnaire, Maternal Behavior Q-sort Manual Version 3.1 and Olson's marital questionnaire, respectively. A self-formulated questionnaire of family environment factors was completed by the infant's mother. Of the 160 infants, 68.2% were rated as securely attached (B) and 31.8% as insecurely attached. Of those infants rated as insecurely attached, 7.5% were characterized as avoidant (A), 21.8% as resistant (C) and 2.5% as disorganized (D). Maternal sensitivity and marital satisfaction as well as the approachability dimension of infant temperament, were significantly different between securely attached infants and insecurely attached infants. From a temperament perspective, resistant infants showed higher-level intensity of reaction than avoidant infants. Moreover, multiple caregivers in the family and infant's sleeping with other caregivers at night were more likely to be associated with insecure mother-infant attachment. There exist certain cultural characteristics in mother-infant attachment patterns in Shanghai. The influence factors are related with the high involvement of non-mother caregivers as well as maternal sensitivity, marital satisfaction and infant's temperament characteristics. Copyright © 2011 Elsevier Ltd. All rights reserved.
The inter-relations of mother and father attachment, self-esteem and aggression during late adolescence.

PubMed

Gomez, Rapson; McLaren, Suzanne

2007-01-01

This study examined three models depicting the relations between mother and father attachment, self-esteem and aggression. A total of 385 participants (173 males and 212 females), aged from 18 to 20 years, completed self-rating questionnaires covering mother and father attachment, self-esteem and aggression. Results showed that self-esteem had additive and mediation effects on both the father attachment-aggression and mother attachment-aggression relationships, and also moderated the mother attachment-aggression relation. These findings are discussed in terms of different models for the inter-relations of mother and father attachment, self-esteem and aggression in late adolescence. Copyright 2006 Wiley-Liss, Inc.
Kinetic studies on the removal of phenol by MBBR from saline wastewater.

PubMed

Ahmadi, Mehdi; Jaafarzadeh, Neamat; Rahmat, Zeinab Ghaed; Babaei, Ali Akbar; Alavi, Nadali; Baboli, Zeinab; Niri, Mehdi Vosoughi

2017-01-01

Phenols are chemical compounds which are included in the high priority of pollutants by environmental protection agency (USEPA). The presence of high concentrations of phenols in wastewaters like oil refineries, petrochemical plants, olive oil, pesticide production and oil field operations contain high soluble solids (TDS) and in an olive oil plant, wastewater is acidic, high salty and phenol concentrations are in the range of 0.1- 1%. Kinetic parameters were calculated according to Monod, Modified Stover- Kincannon, Hamoda and Haldane models. The influence of different initial phenol concentrations on the biodegradation rate was performed. The concentrations of phenol varied from 0 to 500 mg / l. The value of K i in saline phenolic wastewater in attached growth systems was higher than suspended growth systems that represented a higher phenol inhibition in suspended growth systems. It was obvious that the best model fitting the obtained data are Hamoda model and the Modified Stover-Kincannon model, having highest R 2 values of 0.991 and 1, respectively. The value of K i in saline phenolic wastewater in attached growth system was higher than suspended growth systems which represented a higher phenol inhibition in suspended growth systems. Hamoda model and the Modified Stover-Kincannon model having highest R2 value of 0.991 and 1, respectively, and also predicting reasonable kinetic coefficient values.
Genetic and attachment influences on adolescents' regulation of autonomy and aggressiveness.

PubMed

Zimmermann, Peter; Mohr, Cornelia; Spangler, Gottfried

2009-11-01

Adolescence is a time when intense emotions are elicited within the parent-adolescent relationship, often when autonomy subjectively is endangered. As emotion dysregulation is one of the risk processes for the development of psychopathology, adolescence may be perceived as a highly sensitive period for maladjustment. Inter-individual differences in emotionality and emotion regulation have been shown to be influenced or moderated by molecular genetic differences in the serotonin transporter gene (5-HTT) and by attachment patterns. We investigated whether both the 5-HTT and attachment are associated with emotionality and emotion regulation in an observed adolescent-mother interaction and the personality traits aggressiveness and anxiety in adolescence. Ninety-one adolescents at age 12 were observed in interaction with their mothers during a standardized emotion-eliciting social task to assess emotionality and emotion regulation in relation to autonomy. Adolescents' aggressiveness and anxiety were assessed by mother report. Concurrent attachment quality was determined by an attachment interview. DNA samples were collected in order to assess the 5-HTTLPR, a repeat polymorphism in the promoter region of the serotonin transporter gene. While the short allele of the serotonin transporter gene was associated with a higher overall rate of autonomy behaviors, attachment security was related to more agreeable and less hostile autonomy. A significant interaction revealed a moderating effect of attachment security. Carriers of the short version of the 5-HTTLPR showed more agreeable autonomy when they had a secure attachment behavior strategy but showed more hostile autonomy when they were insecurely attached. Carriers of the short version of the 5-HTTLPR and insecurely attached adolescents were rated as more aggressive. The study suggests a gene-attachment interaction in adolescents where the adolescent's attachment status moderates a genetically based higher negative reactivity in response to threats to autonomy in social interactions.
Atmospheric Removal of Very Long-lived Greenhouse Gases in the Mesosphere

NASA Astrophysics Data System (ADS)

Totterdill, A.; Kovacs, T.; Gomez Martin, J.; FENG, W.; Chipperfield, M.; Plane, J. M.

2013-12-01

Chlorofluorocarbons are known to have serious ozone depleting and global warming potentials. Perfluorinated compounds such as SF6, NF3, SF5CF3 and CF3CF2Cl which have very long lifetimes (ranging from a few centuries to over 3000 years) are too stable to affect stratospheric ozone but do have among the highest per molecule radiative forcing of any greenhouse pollutant, making them extremely potent greenhouse gases. Due to the stability of these gases in the lower atmosphere, mesospheric loss processes could significantly reduce their estimated atmospheric lifetimes and hence, overall climate impact. Potential sinks include reactions with metals and energetic particles such as electrons or short wavelength photons already present in the upper atmosphere. The metals, in this instance iron, sodium or potassium, are produced by meteoric ablation, while background and energetic electrons have the continuous source of photoionization and auroral precipitation, respectively. In this study we investigate the removal potentials of four very long lived gases (SF6, NF3, SF5CF3 and CF3CF2Cl). First, by four metals (Fe, Mg, Na and K), where rate coefficients are measured using the Fast Flow Tube and Pulsed Laser Flash Photolysis / Laser Induced Fluorescence techniques. Second, removal by electron attachment was investigated using a quadrupole mass spectrometer. measurements. Third, Lyman-alpha (121.56 nm) photolysis was measured in a VUV absorption cell. The resulting removal rate coefficients are currently being input into the Whole Atmosphere Community Climate Model (WACCM) to obtain lifetime measurements for these species.
Adolescent Attachment Security, Family Functioning, and Suicide Attempts

PubMed Central

Sheftall, Arielle H.; Mathias, Charles W.; Furr, R. Michael; Dougherty, Donald M.

2013-01-01

Theories of suicidal behavior suggest that the desire to die can arise from disruption of interpersonal relationships. Suicide research has typically studied this from the individual's perspective of the quality/frequency of their social interactions; however, the field of attachment may offer another perspective on understanding an individual’s social patterns and suicide risk. This study examined attachment along with broader family functioning (family adaptability and cohesion) among 236 adolescent psychiatric inpatients with (n = 111) and without (n = 125) histories of suicide attempts. On average, adolescents were 14 years of age and Hispanic (69%). Compared to those without suicide attempts, adolescent attempters had lower self-reported maternal and paternal attachment and lower familial adaptability and cohesion. When comparing all 3 types of attachment simultaneously in the logistic regression model predicting suicide attempt status, paternal attachment was the only significant predictor. Suicide attempt group was also significantly predicted by self-rated Cohesion and Adaptability; neither of the parent ratings of family functioning were significant predictors. These findings are consistent with the predictions of the Interpersonal Theory of Suicide about social functioning and support the efforts to develop attachment-based interventions as a novel route towards suicide prevention. PMID:23560608
Adolescent attachment security, family functioning, and suicide attempts.

PubMed

Sheftall, Arielle H; Mathias, Charles W; Furr, R Michael; Dougherty, Donald M

2013-01-01

Theories of suicidal behavior suggest that the desire to die can arise from disruption of interpersonal relationships. Suicide research has typically studied this from the individual's perspective of the quality/frequency of their social interactions; however, the field of attachment may offer another perspective on understanding an individual's social patterns and suicide risk. This study examined attachment along with broader family functioning (family adaptability and cohesion) among 236 adolescent psychiatric inpatients with (n = 111) and without (n = 125) histories of suicide attempts. On average, adolescents were 14 years of age and Hispanic (69%). Compared to those without suicide attempts, adolescent attempters had lower self-reported maternal and paternal attachment and lower familial adaptability and cohesion. When comparing all three types of attachment simultaneously in the logistic regression model predicting suicide attempt status, paternal attachment was the only significant predictor. Suicide attempt group was also significantly predicted by self-rated Cohesion and Adaptability; neither of the parent ratings of family functioning were significant predictors. These findings are consistent with the predictions of the Interpersonal Theory of Suicide about social functioning and support the efforts to develop attachment-based interventions as a novel route towards suicide prevention.
Sleep architecture and sleep-related mentation in securely and insecurely attached people

PubMed Central

McNamara, Patrick; Pace-Schott, Edward F.; Johnson, Patricia; Harris, Erica; Auerbach, Sanford

2011-01-01

Based on REM sleep’s brain activation patterns and its participation in consolidation of emotional memories, we tested the hypothesis that measures of REM sleep architecture and REM sleep-related mentation would be associated with attachment orientation. After a habituation night in a sleep lab, a convenience sample of 64 healthy volunteers were awakened 10 minutes into a REM sleep episode and 10 minutes into a control NREM sleep episode in counterbalanced order, then asked to report a dream and to rate themselves and a significant other on a list of trait adjectives. Relative to participants classified as having secure attachment orientations, participants classified as anxious took less time to enter REM sleep and had a higher frequency of REM dreams with aggression and self-denigrating themes. There were no significant differences across attachment groups in other measures of sleep architecture or in post REM-sleep awakening ratings on PANAS subscales reflecting mood and alertness. Selected aspects of REM sleep architecture and mentation appeared to be associated with attachment orientation. We suggest that REM sleep plays a role in processing experiences and emotions related to attachment, and that certain features of sleep and dreaming reflect attachment orientations. PMID:21390907
Attachment Insecurity Predicts Punishment Sensitivity in Anorexia Nervosa.

PubMed

Keating, Charlotte; Castle, David J; Newton, Richard; Huang, Chia; Rossell, Susan L

2016-10-01

Individuals with anorexia nervosa (AN) experience insecure attachment. We investigated whether insecure attachment is associated with punishment and reward sensitivity in women with AN. Women with AN (n = 24) and comparison women (n = 26) (CW) completed The Eating Disorder Examination Questionnaire, Depression Anxiety Stress Scale, The Attachment Style Questionnaire, and Sensitivity to Punishment/Sensitivity to Reward Questionnaire. Participants with AN returned higher ratings for insecure attachment (anxious and avoidant) experiences and greater sensitivity to punishment (p = 0.001) than CW. In AN, sensitivity to punishment was positively correlated with anxious attachment and negative emotionality but not eating disorder symptoms. Regression analysis revealed that anxious attachment independently predicted punishment sensitivity in AN. Anxious attachment experiences are related to punishment sensitivity in AN, independent of negative emotionality and eating disorder symptoms. Results support ongoing investigation of the contribution of attachment experiences in treatment and recovery.
Colloid transport in saturated porous media: Elimination of attachment efficiency in a new colloid transport model

USGS Publications Warehouse

Landkamer, Lee L.; Harvey, Ronald W.; Scheibe, Timothy D.; Ryan, Joseph N.

2013-01-01

A colloid transport model is introduced that is conceptually simple yet captures the essential features of colloid transport and retention in saturated porous media when colloid retention is dominated by the secondary minimum because an electrostatic barrier inhibits substantial deposition in the primary minimum. This model is based on conventional colloid filtration theory (CFT) but eliminates the empirical concept of attachment efficiency. The colloid deposition rate is computed directly from CFT by assuming all predicted interceptions of colloids by collectors result in at least temporary deposition in the secondary minimum. Also, a new paradigm for colloid re-entrainment based on colloid population heterogeneity is introduced. To accomplish this, the initial colloid population is divided into two fractions. One fraction, by virtue of physiochemical characteristics (e.g., size and charge), will always be re-entrained after capture in a secondary minimum. The remaining fraction of colloids, again as a result of physiochemical characteristics, will be retained “irreversibly” when captured by a secondary minimum. Assuming the dispersion coefficient can be estimated from tracer behavior, this model has only two fitting parameters: (1) the fraction of the initial colloid population that will be retained “irreversibly” upon interception by a secondary minimum, and (2) the rate at which reversibly retained colloids leave the secondary minimum. These two parameters were correlated to the depth of the Derjaguin-Landau-Verwey-Overbeek (DLVO) secondary energy minimum and pore-water velocity, two physical forces that influence colloid transport. Given this correlation, the model serves as a heuristic tool for exploring the influence of physical parameters such as surface potential and fluid velocity on colloid transport.
Adult attachment as a moderator of treatment outcome for generalized anxiety disorder: Comparison between cognitive-behavioral therapy (CBT) plus supportive listening and CBT plus interpersonal and emotional processing therapy.

PubMed

Newman, Michelle G; Castonguay, Louis G; Jacobson, Nicholas C; Moore, Ginger A

2015-10-01

To determine whether baseline dimensions of adult insecure attachment (avoidant and anxious) moderated outcome in a secondary analysis of a randomized controlled trial comparing cognitive-behavioral therapy (CBT) plus supportive listening (CBT + SL) versus CBT plus interpersonal and emotional processing therapy (CBT + I/EP). Eighty-three participants diagnosed with generalized anxiety disorder (GAD) were recruited from the community and assigned randomly to CBT + SL (n = 40) or to CBT + I/EP (n = 43) within a study using an additive design. PhD-level psychologists treated participants. Blind assessors evaluated participants at pretreatment, posttreatment, 6-month, 12-month, and 2-year follow-up with a composite of self-report and assessor-rated GAD symptom measures (Penn State Worry Questionnaire, Hamilton Anxiety Rating Scale, Clinician's Severity Rating). Avoidant and anxious attachment were assessed using self-reported dismissing and angry states of mind, respectively, on the Perceptions of Adult Attachment Questionnaire. Consistent with our prediction, at all assessments higher levels of dismissing styles in those who received CBT + I/EP predicted greater change in GAD symptoms compared with those who received CBT + SL for whom dismissiveness was unrelated to the change. At postassessment, higher angry attachment was associated with less change in GAD symptoms for those receiving CBT + I/EP, compared with CBT + SL, for whom anger was unrelated to change in GAD symptoms. Pretreatment attachment-related anger failed to moderate outcome at other time points and therefore, these moderation effects were more short-lived than the ones for dismissing attachment. When compared with CBT + SL, CBT + I/EP may be better for individuals with GAD who have relatively higher dismissing styles of attachment. (c) 2015 APA, all rights reserved).
Analytical coupled modeling of a magneto-based acoustic metamaterial harvester

NASA Astrophysics Data System (ADS)

Nguyen, H.; Zhu, R.; Chen, J. K.; Tracy, S. L.; Huang, G. L.

2018-05-01

Membrane-type acoustic metamaterials (MAMs) have demonstrated unusual capacity in controlling low-frequency sound transmission, reflection, and absorption. In this paper, an analytical vibro-acoustic-electromagnetic coupling model is developed to study MAM harvester sound absorption, energy conversion, and energy harvesting behavior under a normal sound incidence. The MAM harvester is composed of a prestressed membrane with an attached rigid mass, a magnet coil, and a permanent magnet coin. To accurately capture finite-dimension rigid mass effects on the membrane deformation under the variable magnet force, a theoretical model based on the deviating acoustic surface Green’s function approach is developed by considering the acoustic near field and distributed effective shear force along the interfacial boundary between the mass and the membrane. The accuracy and capability of the theoretical model is verified through comparison with the finite element method. In particular, sound absorption, acoustic-electric energy conversion, and harvesting coefficient are quantitatively investigated by varying the weight and size of the attached mass, prestress and thickness of the membrane. It is found that the highest achievable conversion and harvesting coefficients can reach up to 48%, and 36%, respectively. The developed model can serve as an efficient tool for designing MAM harvesters.
Autobiographical Memory Phenomenology and Content Mediate Attachment Style and Psychological Distress

ERIC Educational Resources Information Center

Sutin, Angelina R.; Gillath, Omri

2009-01-01

In 2 studies, the present research tested the phenomenology and content of autobiographical memory as distinct mediators between attachment avoidance and anxiety and depressive symptoms. In Study 1, participants (N = 454) completed measures of attachment and depressive symptoms in 1 session and retrieved and rated 2 self-defining memories of…
Is therapist evaluation of Social Anxiety/Avoidance traits associated with patient-reported attachment style?

PubMed

Katz, Michael; Hilsenroth, Mark J

2017-11-01

The Social Anxiety/Avoidance Scale was recently added to the Shedler Westen Assessment Procedure (SWAP), and requires independent validation. This study used data drawn from a larger ongoing project in order to retrospectively examine its convergent validity with two self-report attachment measures: Relationship Questionnaire (RQ) and Experiences in Close Relationships Questionnaire-Revised (ECR-R). Fifty-two patients completed the RQ and the ECR-R before beginning psychotherapy treatment. Clinicians rated the patients on the SWAP after six sessions. The SWAP Social Anxiety/Avoidance Scale (SWAP-SAAS) was negatively related to the RQ secure attachment prototype scale and positively related to the ECR-R attachment anxiety scale. Our findings provide initial support for the use of the SWAP-SAAS as a therapist-rated measure associated with lower patient-reported levels of fit with a secure attachment prototype and with higher patient-reported levels of attachment anxiety. Implications and suggestions for future research on the SWAP-SAAS, as well as for clinical work with socially anxious and avoidant patients, are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.
Characterizing the reflectivity of handheld display devices.

PubMed

Liu, Peter; Badano, Aldo

2014-08-01

With increased use of handheld and tablet display devices for viewing medical images, methods for consistently measuring reflectivity of the devices are needed. In this note, the authors report on the characterization of diffuse reflections for handheld display devices including mobile phones and tablets using methods recommended by the American Association of Physicists in Medicine Task Group 18 (TG18). The authors modified the diffuse reflectance coefficient measurement method outlined in the TG18 report. The authors measured seven handheld display devices (two phones and five tablets) and three workstation displays. The device was attached to a black panel with Velcro. To study the effect of the back surface on the diffuse reflectance coefficient, the authors created Styrofoam masks with different size square openings and placed it in front of the device. Overall, for each display device, measurements of illuminance and reflected luminance on the display screen were taken. The authors measured with no mask, with masks of varying size, and with display-size masks, and calculated the corresponding diffuse reflectance coefficient. For all handhelds, the diffuse reflectance coefficient measured with no back panel were lower than measurements performed with a mask. The authors found an overall increase in reflectivity as the size of the mask decreases. For workstations displays, diffuse reflectance coefficients were higher when no back panel was used, and higher than with masks. In all cases, as luminance increased, illuminance increased, but not at the same rate. Since the size of handheld displays is smaller than that of workstation devices, the TG18 method suffers from a dependency on illumination condition. The authors show that the diffuse reflection coefficients can vary depending on the nature of the back surface of the illuminating box. The variability in the diffuse coefficient can be as large as 20% depending on the size of the mask. For all measurements, both luminance and illuminance increased as the size of the display window decreased. The TG18 method does not account for this variability. The authors conclude that the method requires a definitive description of the back panel used in the light source setup. The methods described in the TG18 document may need to be improved to provide consistent comparisons of desktop monitors, phones, and tablets.
Exhaust ventilation in attached garages improves residential indoor air quality.

PubMed

Mallach, G; St-Jean, M; MacNeill, M; Aubin, D; Wallace, L; Shin, T; Van Ryswyk, K; Kulka, R; You, H; Fugler, D; Lavigne, E; Wheeler, A J

2017-03-01

Previous research has shown that indoor benzene levels in homes with attached garages are higher than homes without attached garages. Exhaust ventilation in attached garages is one possible intervention to reduce these concentrations. To evaluate the effectiveness of this intervention, a randomized crossover study was conducted in 33 Ottawa homes in winter 2014. VOCs including benzene, toluene, ethylbenzene, and xylenes, nitrogen dioxide, carbon monoxide, and air exchange rates were measured over four 48-hour periods when a garage exhaust fan was turned on or off. A blower door test conducted in each garage was used to determine the required exhaust fan flow rate to provide a depressurization of 5 Pa in each garage relative to the home. When corrected for ambient concentrations, the fan decreased geometric mean indoor benzene concentrations from 1.04 to 0.40 μg/m 3 , or by 62% (P<.05). The garage exhaust fan also significantly reduced outdoor-corrected geometric mean indoor concentrations of other pollutants, including toluene (53%), ethylbenzene (47%), m,p-xylene (45%), o-xylene (43%), and carbon monoxide (23%) (P<.05) while having no impact on the home air exchange rate. This study provides evidence that mechanical exhaust ventilation in attached garages can reduce indoor concentrations of pollutants originating from within attached garages. © 2016 Her Majesty the Queen in Right of Canada. Indoor Air published by John Wiley & Sons Ltd.
Direct Determination of the Rate Coefficient for the Reaction of OH Radicals with Monoethanol Amine (MEA) from 296 to 510 K.

PubMed

Onel, L; Blitz, M A; Seakins, P W

2012-04-05

Monoethanol amine (H2NCH2CH2OH, MEA) has been proposed for large-scale use in carbon capture and storage. We present the first absolute, temperature-dependent determination of the rate coefficient for the reaction of OH with MEA using laser flash photolysis for OH generation, monitoring OH removal by laser-induced fluorescence. The room-temperature rate coefficient is determined to be (7.61 ± 0.76) × 10(-11) cm(3) molecule(-1) s(-1), and the rate coefficient decreases by about 40% by 510 K. The temperature dependence of the rate coefficient is given by k1= (7.73 ± 0.24) × 10(-11)(T/295)(-(0.79±0.11)) cm(3) molecule(-1) s(-1). The high rate coefficient shows that gas-phase processing in the atmosphere will be competitive with uptake onto aerosols.
Characteristics of atmospheric Ar/NH3 DBD and its comparison with He/N2 DBD

NASA Astrophysics Data System (ADS)

Yao, Congwei; Chen, Sile; Wang, Shuai; Chang, Zhengshi; Sun, Anbang; Mu, Haibao; Zhang, Guan-Jun

2018-06-01

The discharge mode and photoelectric characteristics of Ar/NH3 DBD (dielectric barrier discharge) are studied to discuss the stability of the discharge under the influence of Penning ionization and attachment reaction. There are three discharge modes, including stable uniform glow discharge, unstable glow discharge and unstable columnar discharge. Discharge instability, including nonuniform discharge and discharge channel split, occurs under low (<0.10%) or high (>0.35%) volume fractions of NH3, which are understood to be caused by an insufficiently strong Penning effect or a strong attachment reaction, respectively. The attachment reaction of NH3 can also lead to a weaker emission intensity for Ar/NH3 DBD, in particular regarding the emission of OH(A2Σ+). Ar/NH3 and He/N2 DBDs are also compared. In He/N2 DBD, the emission intensity of OH(A2Σ+) changes less with increasing N2 volume fraction, which may be attributed to the lack of attachment reaction. Compared with Ar/NH3 DBD, the single discharge channel in He/N2 DBD is narrower, but the discharge area is wider, which should be induced by the higher Townsend ionization coefficient nonlinearity of He/N2 and the absence of attachment reaction in He/N2, respectively. In the end, a one-dimensional fluid model of Ar/NH3 DBD is built to verify the explanation of experimental results.

Solvent dependence of the activation energy of attachment determined by single molecule observations of surfactant adsorption.

PubMed

Honciuc, Andrei; Baptiste, Denver Jn; Campbell, Ian P; Schwartz, Daniel K

2009-07-07

Single-molecule total internal reflection fluorescence microscopy was used to obtain real-time images of fluorescently labeled hexadecanoic (palmitic) acid molecules as they adsorbed at the interface between fused silica and three different solvents: hexadecane (HD), tetrahydrofuran (THF), and water. These solvents were chosen to explore the effect of solvent polarity on the activation energy associated with the attachment rate, i.e., the rate at which molecules were transferred to the surface from the near-surface layer. Direct counting of single-molecule events, made under steady-state conditions at extremely low coverage, provided direct, model-independent measurements of this attachment rate, in contrast with conventional ensemble-averaged methods, which are influenced by bulk transport and competing detachment processes. We found that the attachment rate increased with increasing temperature for all solvents. Arrhenius analyses gave activation energies of 5+/-2 kJ/mol for adsorption from HD, 10+/-2 kJ/mol for adsorption from THF, and 19+/-2 kJ/mol for adsorption from water. These energies increased systematically with the solvent polarity and, therefore, with the expected strength of the solvent-substrate interaction. We hypothesize that the adsorption of amphiphilic solute molecules from solution can be regarded as a competitive exchange between solute molecules and surface-bound solvent. In this scenario, adsorption is an activated process, and the activation energy for attachment is associated with the solvent-substrate interaction energy.
Recollections of Parent Characteristics and Attachment Patterns for College Women of Intact vs. Non-Intact Families

ERIC Educational Resources Information Center

Kilmann, Peter R.; Carranza, Laura V.; Vendemia, Jennifer M. C.

2006-01-01

This study contrasted offsprings' attachment patterns and recollections of parent characteristics in two college samples: 147 females from intact biological parents and 157 females of parental divorce. Secure females from intact or non-intact families rated parents positively, while insecure females rated parents as absent, distant, and demanding.…
Developmental trajectories and longitudinal mediation effects of self-esteem, peer attachment, child maltreatment and depression on early adolescents.

PubMed

Ju, Soyoung; Lee, Yanghee

2018-02-01

The purpose of this study is to identify the developmental trajectories of peer attachment, self-esteem, depression, and child maltreatment, and to understand the longitudinal mediation effects that peer attachment and self-esteem have on the influence of perceived abuse on early adolescent depression. This study uses Year 1 to Year 5 data of the 4th grader panel of the Korea Youth Panel Survey (KYPS) and utilizes a multivariate latent growth model to analyze the main variables in the applicable data between 5th (i.e., Year 2) and 8th (i.e., Year 5) grades. The results indicate that from the 5th to the 8th grade, the degree of abuse and depression increases while self-esteem gradually decreases with slowly lowering peer attachment. A significant distribution of the initial values and the rate of change were present for all main variables of the study, confirming individual differences in time wise changes. Further, more exposure to abuse correlated with a decrease in self-esteem, while an increase in self-esteem greatly reduced depression. The initial value of self-esteem showed a partial mediation effect, whereas the rate of change indicated a full mediation effect with a significant longitudinal mediation effect. More experience of abuse during early adolescence indicated a lower degree of peer attachment, and a higher peer attachment was related to decreased depression. A significant partial mediation effect was present for both the initial value and the rate of change of peer attachment, and a longitudinal mediation effect was present. This study confirmed that self-esteem in early adolescents is an important protective factor that can greatly reduce the degree of depression, and suggests continuous interventions conducted to increase self-esteem in adolescence. Furthermore, by determining that peer attachment decreases the degree of depression in children at risk, the study emphasizes the healing aspect of adolescent peer attachment. Copyright © 2017 Elsevier Ltd. All rights reserved.
Change in attachment states of mind of women with binge-eating disorder.

PubMed

Maxwell, Hilary; Tasca, Giorgio A; Grenon, Renee; Ritchie, Kerri; Bissada, Hany; Balfour, Louise

2017-11-01

Insecure and unresolved/disorganized attachment states of mind may impact affect regulation and interpersonal functioning that contribute to binge eating in women with binge-eating disorder (BED). Group psychological treatment may facilitate changes from insecure to secure and from unresolved-disorganized to non-unresolved/disorganized attachment states of mind. This study used attachment theory to understand better the psychopathology of BED and co-morbid overweight status and to understand better the treatment response of patients with BED who receive group psychotherapy. Women with BED attended group psychodynamic interpersonal psychotherapy and completed the Adult Attachment Interview pretreatment and 6 months posttreatment. Matched samples of overweight women without BED and normal-weight women without BED completed the Adult Attachment Interview at 1 time point. Women with BED had significantly higher rates of preoccupied and unresolved/disorganized attachment states of mind compared to normal-weight women without BED and had similar rates of insecure and unresolved/disorganized attachment states of mind compared to overweight women without BED. Of the women with BED who had an insecure and/or unresolved/disorganized attachment states of mind at pretreatment, about 60% demonstrated clinically relevant changes to secure and to non-unresolved/disorganized states of mind at 6 months post group psychodynamic interpersonal psychotherapy. Results indicated that some women with BED may benefit from interventions that help them regulate hyperactivated affect and create coherent narratives. Both women with BED and overweight women without BED may benefit from treatments that help them develop more adaptive affect regulation strategies related to unresolved/disorganized attachment states of mind. Copyright © 2017 John Wiley & Sons, Ltd.
Influence of substrate diffusion on degradation of dibenzofuran and 3-chlorodibenzofuran by attached and suspended bacteria.

PubMed Central

Harms, H; Zehnder, A J

1994-01-01

Dibenzofuran uptake-associated kinetic parameters of suspended and attached Sphingomonas sp. strain HH19k cells were compared. The suspended cells were studied in a batch system, whereas glass beads in percolated columns were used as the solid support for attached cells. The maximum specific activities of cells in the two systems were the same. The apparent half-maximum uptake rate-associated concentrations (Kt') of attached cells, however, were considerably greater than those of suspended cells and depended on cell density and on percolation velocity. A mathematical model was developed to explain the observed differences in terms of substrate transport to the cells. This model was based on the assumptions that the intrinsic half-maximum uptake rate-associated concentration (Kt) was unchanged and that deviations of Kt' from Kt resulted from the stereometry and the hydrodynamics around the cells. Our calculations showed that (i) diffusion to suspended cells and to single attached cells is efficient and therefore only slightly affects Kt'; (ii) diffusion to cells located on crowded surfaces is considerably lower than that to single attached cells and greatly increases Kt', which depends on the cell density; (iii) the convective-diffusive transport to attached cells that occurs in a percolated column is influenced by the liquid flow and results in dependency of Kt' on the flow rate; and (iv) higher specific affinity of cells correlates with higher susceptibility to diffusion limitation. Properties of the experimental system which limited quantitative proof of exclusively transport-controlled variations of Kt' are discussed. PMID:8085817
[The reasons why 13 MK1 attachment were re-fabricated and some methods for improvement].

PubMed

Wu, Zhi-hong; Zhang, Xue-jun; Zhao, Jun

2013-12-01

To investigate the reasons why 13 MK1 attachment were re-fabricated and to suggest some improvement methods. Mechanics and denture production technology were reviewed in 13 cases with MK1 attachment denture to determine the causes of failure. In some cases, MK1 attachments were poorly designed, while in other cases problems were found during denture design and production process due to limited experiences at the initial stage. MK1 attachments were re-done based on the specific cause and the outcome was good after 1-1.5 years of follow-up. When using MK1 attachment, prosthodontists should be familiar with the characteristics and indications of MK1 attachment. Meanwhile, we should strengthen doctor-patient communication and follow up patients timely to improve the success rate of MK1 attached denture repair.
Mechanism of thermal electron attachment to NO/sub 2/

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shimamori, H.; Hotta, H.

1986-03-15

The mechanism of thermal electron attachment to NO/sub 2/ has been reexamined by observing the dependence of the attachment rates on the nature and the pressure of the environmental gases. Measurements for mixtures of NO/sub 2/ with rare gases, H/sub 2/, D/sub 2/, N/sub 2/, CO/sub 2/, and n-C/sub 4/H/sub 10/ all showed two-body pressure dependence of the attachment rates at buffer-gas pressures of about 10 to 100 Torr. They gave the same two-body rate constant of (1.13 +- 0.07) x 10/sup -10/ cm/sup 3/ molecule/sup -1/ s/sup -1/. The latter result disagrees with the data reported by Mahan andmore » Walker in 1967. The present results indicate that the collisional electron detachment process introduced previously to interpret the effect of the nature of environmental gases should be negligible. We have also observed the decrease of the two-body rate constants at pressures below about 10 Torr for all the mixtures studied. This strongly suggests that the attachment mechanism is an ordinary two-step three-body process. The three-body rate constants then obtained are mostly of the orders of 10/sup -27/ cm/sup 6/ molecule/sup -2/ s/sup -1/ and do not differ much with nature of the third bodies. An autoionization lifetime of 1 x 10/sup -8/ s has been estimated for the transient-negative ion of NO/sub 2/. It has been found that even room light could cause appreciable decrease of the rate constants, probably through decomposition of NO/sub 2/ molecules. The discrepancy between the present results and the previous ones may be due to such an effect.« less
Attachment Status in Children Prenatally Exposed to Cocaine and Other Substances

ERIC Educational Resources Information Center

Seifer, Ronald; LaGasse, Linda L.; Lester, Barry; Bauer, Charles R.; Shankaran, Seetha; Bada, Henrietta S.; Wright, Linda L.; Smeriglio, Vincent L.; Liu, Jing

2004-01-01

Attachment status of children exposed in utero to cocaine, opiates, and other substances was examined at 18 months (n=860) and 36 months (n=732) corrected age. Children exposed to cocaine and opiates had slightly lower rates of attachment security (but not disorganization), and their insecurity was skewed toward ambivalent, rather than avoidant,…
Infant-Mother Attachment and the Growth of Externalizing Problems across the Primary-School Years

ERIC Educational Resources Information Center

Pasco Fearon, R. M.; Belsky, Jay

2011-01-01

Background: Some contend that attachment insecurity increases risk for the development of externalizing behavior problems in children. Method: Latent-growth curve analyses were applied to data on 1,364 children from the NICHD Study of Early Child Care to evaluate the association between early attachment and teacher-rated externalizing problems…
The Role of Sociodemographic Risk and Maternal Behavior in the Prediction of Infant Attachment Disorganization

PubMed Central

Gedaly, Lindsey R.; Leerkes, Esther M.

2017-01-01

Predictors of infant attachment disorganization were examined among 203 primiparous mothers (52% European American, 48% African American) and their infants (104 female). The Strange Situation Procedure was administered at 1 year. Global maternal insensitivity and overtly negative maternal behavior were observed during distress-eliciting tasks when infants were 6 months and 1 year old. Mothers reported on their demographics to yield a measure of sociodemographic risk (i.e., age, education, income-to-needs). Overtly negative maternal behavior was positively associated with the infant attachment disorganization rating scale score, but did not predict being classified as disorganized. Global maternal insensitivity was associated with higher attachment disorganization, both the rating and the classification, when sociodemographic risk was high but not when sociodemographic risk was low. The pattern of results did not vary by maternal race. The results provide some support for the view that negative maternal behavior and the combination of sociodemographic risk and global maternal insensitivity play a role in the development of infant attachment disorganization. PMID:27477050
The role of sociodemographic risk and maternal behavior in the prediction of infant attachment disorganization.

PubMed

Gedaly, Lindsey R; Leerkes, Esther M

2016-12-01

Predictors of infant attachment disorganization were examined among 203 primiparous mothers (52% European American, 48% African American) and their infants (104 female). The Strange Situation Procedure was administered at one year. Global maternal insensitivity and overtly negative maternal behavior were observed during distress-eliciting tasks when infants were six months and one year old. Mothers reported on their demographics to yield a measure of sociodemographic risk (i.e., age, education, income-to-needs). Overtly negative maternal behavior was positively associated with the infant attachment disorganization rating scale score, but did not predict being classified as disorganized. Global maternal insensitivity was associated with higher attachment disorganization, both the rating and the classification, when sociodemographic risk was high but not when sociodemographic risk was low. The pattern of results did not vary by maternal race. The results provide some support for the view that negative maternal behavior and the combination of sociodemographic risk and global maternal insensitivity play a role in the development of infant attachment disorganization.
A review of attachment theory in the context of adolescent parenting.

PubMed

Flaherty, Serena Cherry; Sadler, Lois S

2011-01-01

The purpose of this article is to review attachment theory and relate the attachment perspective to adolescent mothers and their children. Attachment theory explains positive maternal-infant attachment as a dyadic relationship between the infant and mother that provides the infant with a secure base from which to explore the world. With respect to cognitive, social, and behavioral domains, securely attached infants tend to have more favorable long-term outcomes, while insecurely attached infants are more likely to have adverse outcomes. Adolescent parenthood can disrupt normal adolescent development, and this disruption influences development of the emotional and cognitive capacities necessary for maternal behaviors that foster secure attachment. However, it appears that if specialized supports are in place to facilitate the process of developing attachment, infants of adolescent mothers can obtain higher rates of secure attachment than normative samples in this population. Copyright © 2011 National Association of Pediatric Nurse Practitioners. Published by Mosby, Inc. All rights reserved.
The excitation of OH by H2 revisited - I: fine-structure resolved rate coefficients

NASA Astrophysics Data System (ADS)

Kłos, J.; Ma, Q.; Dagdigian, P. J.; Alexander, M. H.; Faure, A.; Lique, F.

2017-11-01

Observations of OH in molecular clouds provide crucial constraints on both the physical conditions and the oxygen and water chemistry in these clouds. Accurate modelling of the OH emission spectra requires the calculation of rate coefficients for excitation of OH by collisions with the most abundant collisional partner in the molecular clouds, namely the H2 molecule. We report here theoretical calculations for the fine-structure excitation of OH by H2 (both para- and ortho-H2) using a recently developed highly accurate potential energy surface. Full quantum close coupling rate coefficients are provided for temperatures ranging from 10 to 150 K. Propensity rules are discussed and the new OH-H2 rate coefficients are compared to the earlier values that are currently used in astrophysical modelling. Significant differences were found: the new rate coefficients are significantly larger. As a first application, we simulate the excitation of OH in typical cold molecular clouds and star-forming regions. The new rate coefficients predict substantially larger line intensities. As a consequence, OH abundances derived from observations will be reduced from the values predicted by the earlier rate coefficients.
University of São Paulo Reasons for Smoking Scale: a new tool for the evaluation of smoking motivation.

PubMed

Souza, Elisa Sebba Tosta de; Crippa, José Alexandre de Souza; Pasian, Sonia Regina; Martinez, José Antônio Baddini

2010-01-01

To develop a new scale aimed at evaluating smoking motivation by incorporating questions and domains from the 68-item Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) into the Modified Reasons for Smoking Scale (MRSS). Nine WISDM-68 questions regarding affiliative attachment, cue exposure/associative processes, and weight control were added to the 21 questions of the MRSS. The new scale, together with the Fagerström Test for Nicotine Dependence (FTND), was administered to 311 smokers (214 males; mean age = 37.6 ± 10.8 years; mean number of cigarettes smoked per day = 15.0 ± 9.2), who also provided additional information. We used exploratory factor analysis in order to determine the factor structure of the scale. The influence that certain clinical features had on the scores of the final factor solution was also analyzed. The factor analysis revealed a 21-question solution grouped into nine factors: addiction, pleasure from smoking, tension reduction, stimulation, automatism, handling, social smoking, weight control, and affiliative attachment. For the overall scale, the Cronbach's alpha coefficient was 0.83. Females scored significantly higher for addiction, tension reduction, handling, weight control, and affiliative attachment than did males. The FTND score correlated positively with addiction, tension reduction, stimulation, automatism, social smoking, and affiliative attachment. The number of cigarettes smoked per day was associated with addiction, tension reduction, stimulation, automatism, affiliative attachment, and handling. The level of exhaled CO correlated positively with addiction, automatism, and affiliative attachment. The new scale provides an acceptable framework of motivational factors for smoking, with satisfactory psychometric properties and reliability.
A Binomial Modeling Approach for Upscaling Colloid Transport Under Unfavorable Attachment Conditions: Emergent Prediction of Nonmonotonic Retention Profiles

NASA Astrophysics Data System (ADS)

Hilpert, Markus; Johnson, William P.

2018-01-01

We used a recently developed simple mathematical network model to upscale pore-scale colloid transport information determined under unfavorable attachment conditions. Classical log-linear and nonmonotonic retention profiles, both well-reported under favorable and unfavorable attachment conditions, respectively, emerged from our upscaling. The primary attribute of the network is colloid transfer between bulk pore fluid, the near-surface fluid domain (NSFD), and attachment (treated as irreversible). The network model accounts for colloid transfer to the NSFD of downgradient grains and for reentrainment to bulk pore fluid via diffusion or via expulsion at rear flow stagnation zones (RFSZs). The model describes colloid transport by a sequence of random trials in a one-dimensional (1-D) network of Happel cells, which contain a grain and a pore. Using combinatorial analysis that capitalizes on the binomial coefficient, we derived from the pore-scale information the theoretical residence time distribution of colloids in the network. The transition from log-linear to nonmonotonic retention profiles occurs when the conditions underlying classical filtration theory are not fulfilled, i.e., when an NSFD colloid population is maintained. Then, nonmonotonic retention profiles result potentially both for attached and NSFD colloids. The concentration maxima shift downgradient depending on specific parameter choice. The concentration maxima were also shown to shift downgradient temporally (with continued elution) under conditions where attachment is negligible, explaining experimentally observed downgradient transport of retained concentration maxima of adhesion-deficient bacteria. For the case of zero reentrainment, we develop closed-form, analytical expressions for the shape, and the maximum of the colloid retention profile.
Ceramic blade attachment system

DOEpatents

Frey, G.A.; Jimenez, O.D.

1996-12-03

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed between them. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. A pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade. 4 figs.
Rate Coefficients for the OH + (CHO)2 (Glyoxal) Reaction Between 240 and 400 K

NASA Astrophysics Data System (ADS)

Feierabend, K. J.; Talukdar, R. K.; Zhu, L.; Ravishankara, A. R.; Burkholder, J. B.

2006-12-01

Glyoxal (CHO)2, the simplest dialdehyde, is an end product formed in the atmospheric oxidation of biogenic hydrocarbons, for example, isoprene. As such, glyoxal plays a role in regional air quality and ozone production in certain locations. Glyoxal is lost in the atmosphere via UV photolysis and reaction with OH. However, the currently available rate coefficient data for the OH + glyoxal reaction is limited to a single room- temperature measurement made using the relative rate method. A determination of the rate coefficient temperature dependence is therefore needed for a more complete interpretation of the atmospheric processing of glyoxal. This study reports the rate coefficient for the OH + (CHO)2 reaction measured under pseudo- first-order conditions in OH ([(CHO)2] > 1000 [OH]0). OH radicals were produced using 248 nm pulsed laser photolysis of H2O2 or HNO3 and detected by pulsed laser induced fluorescence. The concentration of glyoxal in the reactor was determined using three independent techniques; gas flow rates as well as in situ UV and IR absorption. The total pressure in the reactor was varied from 40 to 300 Torr (He), and the rate coefficient was found to be independent of pressure over the temperature range studied. The rate coefficient exhibits a negative temperature dependence between 240 and 400 K consistent with the dependence previously observed for many other aldehydes. Our room-temperature rate coefficient is smaller than the relative rate value that is currently recommended for use in atmospheric model calculations. Our measured rate coefficients are discussed with respect to those for other aldehydes. The atmospheric implications of our work will also be discussed.
Subcutaneous anchor attachment increases retention of radio transmitters on Xantus' and marbled murrelets

USGS Publications Warehouse

Newman, Scott H.; Takekawa, John Y.; Whitworth, Darrell L.; Burkett, Esther E.

1999-01-01

We modified a subcutaneous anchor attachment and achieved transmitter reten- tion times that exceeded those reported previously for other attachments used on alcids. Traditional suture and epoxy attachment methods were used on Xantus' Murrelets in 1995 and 1996, while the modified attachment was used for Xantus' Murrelets in 1996 and 1997 and Marbled Murrelets in 1997. Modifications included use of an inhalant anesthetic, placing the anchor in a more cranial position on the back, application of marine epoxy, and place- ment of a single subcutaneous non-absorbable suture at the caudal end of the radio to hold the radio in place initially. We located 22 of 56 (39%) Xantus' Murrelets radio-marked using suture and epoxy during aerial surveys in 1995 and 1996. Of birds radio-marked using the subcutaneous anchor attachment, we located 92 of 113 (81%) Xantus' Murrelets marked in 1996 and 1997 and all 28 (100%) Marbled Murrelets marked in 1997 during aerial surveys. The maximum confirmed duration for the subcutaneous anchor transmitter attachment was 51 d for Xantus' Murrelets and 78 d for Marbled Murrelets versus 41 d for the suture and epoxy attachment used on Xantus' Murrelets. Recapture rates of radio-marked Xantus' Mur- relets were similar to recapture rates of unmarked Xantus' Murrelets. Our post-release ob- servations indicated negligible short-term physical effects from the attachment procedure, while telemetry data and examination of recaptured murrelets indicated no evidence of infection or other long-term physical effects. Breeding behavior of some murrelets was not disrupted; however, further evaluation of potential effects of this attachment technique on breeding and behavior is needed.
Hemolytic potential of hydrodynamic cavitation.

PubMed

Chambers, S D; Bartlett, R H; Ceccio, S L

2000-08-01

The purpose of this study was to determine the hemolytic potentials of discrete bubble cavitation and attached cavitation. To generate controlled cavitation events, a venturigeometry hydrodynamic device, called a Cavitation Susceptibility Meter (CSM), was constructed. A comparison between the hemolytic potential of discrete bubble cavitation and attached cavitation was investigated with a single-pass flow apparatus and a recirculating flow apparatus, both utilizing the CSM. An analytical model, based on spherical bubble dynamics, was developed for predicting the hemolysis caused by discrete bubble cavitation. Experimentally, discrete bubble cavitation did not correlate with a measurable increase in plasma-free hemoglobin (PFHb), as predicted by the analytical model. However, attached cavitation did result in significant PFHb generation. The rate of PFHb generation scaled inversely with the Cavitation number at a constant flow rate, suggesting that the size of the attached cavity was the dominant hemolytic factor.
Role of surface properties in bacterial attachment

NASA Astrophysics Data System (ADS)

Conrad, Jacinta; Sharma, Sumedha

2014-03-01

Bacterial biofilms foul a wide range of engineered surfaces, from pipelines to membranes to biomedical implants, and lead to deleterious costs for industry and for human health. Designing strategies to reduce bacterial fouling requires fundamental understanding of mechanisms by which bacteria attach to surfaces. We investigate the attachment of Escherichia coli on silanized glass surfaces during flow through a linear channel at flow rates of 0.1-1 mL/min using confocal microscopy. We deposit self-assembled monolayers of organosilanes on glass and track the position and orientation of bacteria deposited on these surfaces during flow using high-throughput image processing algorithms. Here, we report differences in deposition rate and surface-tethered motion of cells as a function of surface charge and surface energy, suggesting that attachment of bacteria on these engineered surfaces is dominated by different physical mechanisms.

The relationship of attachment insecurity to subjective stress and autonomic function during standardized acute stress in healthy adults.

PubMed

Maunder, Robert G; Lancee, William J; Nolan, Robert P; Hunter, Jonathan J; Tannenbaum, David W

2006-03-01

The purpose of this study was to test predicted relationships between adult attachment and stress using subjective and physiological measures. Sixty-seven healthy adults completed measures of adult attachment and perceived chronic stress. Subjective stress and the high-frequency (HF) and low-frequency (LF) spectral bandwidths of heart rate variability (HRV) were measured during a standardized stress protocol. Attachment anxiety is associated with between-subject differences in chronic perceived stress (P=.001) and subjective acute stress (P=.01). There is a main effect of attachment avoidance on between-subject differences in HF HRV (P=.004). Attachment avoidance is inversely associated with HF HRV, independent of age and variability in respiration. Attachment anxiety is associated with self-reported distress. Attachment avoidance is inversely associated with HF HRV, a marker of vagal influence on cardiac activity, but is not associated with subjective stress.
Estimating inelastic heavy-particle - hydrogen collision data. II. Simplified model for ionic collisions and application to barium-hydrogen ionic collisions

NASA Astrophysics Data System (ADS)

Belyaev, Andrey K.; Yakovleva, Svetlana A.

2017-12-01

Aims: A simplified model is derived for estimating rate coefficients for inelastic processes in low-energy collisions of heavy particles with hydrogen, in particular, the rate coefficients with high and moderate values. Such processes are important for non-local thermodynamic equilibrium modeling of cool stellar atmospheres. Methods: The derived method is based on the asymptotic approach for electronic structure calculations and the Landau-Zener model for nonadiabatic transition probability determination. Results: It is found that the rate coefficients are expressed via statistical probabilities and reduced rate coefficients. It is shown that the reduced rate coefficients for neutralization and ion-pair formation processes depend on single electronic bound energies of an atomic particle, while the reduced rate coefficients for excitation and de-excitation processes depend on two electronic bound energies. The reduced rate coefficients are calculated and tabulated as functions of electronic bound energies. The derived model is applied to barium-hydrogen ionic collisions. For the first time, rate coefficients are evaluated for inelastic processes in Ba+ + H and Ba2+ + H- collisions for all transitions between the states from the ground and up to and including the ionic state. Tables with calculated data are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/608/A33
Estimating inelastic heavy-particle-hydrogen collision data. I. Simplified model and application to potassium-hydrogen collisions

NASA Astrophysics Data System (ADS)

Belyaev, Andrey K.; Yakovleva, Svetlana A.

2017-10-01

Aims: We derive a simplified model for estimating atomic data on inelastic processes in low-energy collisions of heavy-particles with hydrogen, in particular for the inelastic processes with high and moderate rate coefficients. It is known that these processes are important for non-LTE modeling of cool stellar atmospheres. Methods: Rate coefficients are evaluated using a derived method, which is a simplified version of a recently proposed approach based on the asymptotic method for electronic structure calculations and the Landau-Zener model for nonadiabatic transition probability determination. Results: The rate coefficients are found to be expressed via statistical probabilities and reduced rate coefficients. It turns out that the reduced rate coefficients for mutual neutralization and ion-pair formation processes depend on single electronic bound energies of an atom, while the reduced rate coefficients for excitation and de-excitation processes depend on two electronic bound energies. The reduced rate coefficients are calculated and tabulated as functions of electronic bound energies. The derived model is applied to potassium-hydrogen collisions. For the first time, rate coefficients are evaluated for inelastic processes in K+H and K++H- collisions for all transitions from ground states up to and including ionic states. Tables with calculated data are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/606/A147
The Relation between Mother-Infant Interactional Characteristics in Early Infancy and Later Attachment as Assessed in the Strange Situation.

ERIC Educational Resources Information Center

Kanaya, Yuko; Miyake, Kazuo

Maternal and infant interactional characteristics in early infancy were investigated in order to examine their causal relationship with later attachment as assessed in the Strange Situation. Although the results of rating for maternal variables at four months of age exhibited significant differences between the set (S1) composed of attachment type…
Assessing the Use of the Child Attachment Interview in a Sample of Israeli Jewish Children.

PubMed

Baumel, Amit; Wolmer, Leo; Laor, Nathaniel; Toren, Paz

2016-01-01

This manuscript assesses the use of the Child Attachment Interview (CAI) in a sample of Israeli Jewish children in middle childhood in order to add to empirical data on this measure. Forty-one children between the ages of 7 and 13 were consecutively recruited to the study. The clinical sample included 29 children diagnosed with anxiety disorder, major depression or ADHD. The Father Focused Referral (FFR) sample included 12 children whose father was unavailable to them. Participants were administered the CAI and coded by certified personnel. 81.4% concordance was found between maternal and paternal secure-insecure attachment classifications in the clinical sample; 100% of the children in the FFR group were classified as insecurely attached to their fathers suggesting convergent validity for the classification of father attachment; 45.4% of the children in the FFR sample were also classified as insecurely attached to their mothers, pointing to the difference that can be found between the two parental attachment classifications in relevant cases, and therefore to sufficient discriminant validity between the two classifications. The clinical sample concordance rate, which was lower than in previous studies, indicates that parental concordance rates should be further investigated using different samples and countries. The study's findings regarding the difference that can be found between parental attachment classifications show the instrument's relevance in cases which the parental representations may differ. In these cases, using an instrument that does not examine the attachment toward both parents might not suffice. Study limitations and further implications are discussed.
The insecure psychotherapy base: Using client and therapist attachment styles to understand the early alliance.

PubMed

Marmarosh, Cheri L; Kivlighan, Dennis M; Bieri, Kathryn; LaFauci Schutt, Jean M; Barone, Carrie; Choi, Jaehwa

2014-09-01

The purpose of this study was to test the notion that complementary attachments are best for achieving a secure base in psychotherapy. Specifically, we predicted third to fifth session alliance from client- and therapist-rated attachment style interactions. Using a combined sample of 46 therapy dyads from a community mental health clinic and university counseling center, the client- and therapist-perceived therapy alliance, attachment anxiety, and attachment avoidance were examined at the beginning of therapy. The results of an Actor-Partner Interdependence Model (APIM; Kenny & Cook, 1999, Partner effects in relationship research: Conceptual issues, analytic difficulties, and illustrations. Personal Relationships, 6, 433-448.) indicated that there was no direct effect of either client or therapist attachment style on therapist or client early ratings of the alliance. One significant interaction emerged and indicated that client-perceived alliance was influenced by therapist and client attachment anxiety. The client-perceived early alliance was higher when more anxious therapists worked with clients with decreasing anxiety. The client early alliance was higher when less anxious therapists worked with clients with increasing anxiety. The findings partially support the notion that different attachment configurations between the therapist and client facilitate greater alliance, but this was the case only when assessing client-perceived early alliance and only with regards to the dimension of attachment anxiety. There were no significant main effects or interactions when exploring therapist-perceived alliance. Implications of the findings are discussed along with recommendations for future study and clinical training. PsycINFO Database Record (c) 2014 APA, all rights reserved.
MS2 inactivation by TiO2 nanoparticles in the presence of quartz sand

NASA Astrophysics Data System (ADS)

Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

2017-04-01

Virus inactivation by nanoparticles (NPs) is hypothesized to affect virus fate and transport in the subsurface. This study examines the interactions of viruses with titanium dioxide (TiO2) anatase NPs, which is a good disinfectant with unique physiochemical properties, using three different virus concentrations. The bacteriophage MS2 was used as a model virus. A series of batch experiments of MS2 inactivation by TiO2 NPs were conducted at room temperature (25 °C), in the presence of quartz sand, with and without ambient light. The virus inactivation experimental data were satisfactorily fitted with a pseudo-first order expression with a time dependent rate coefficient. Quartz sand was shown to affect MS2 inactivation by TiO2 NPs both in the presence and absence of ambient light, because, under the experimental conditions of this study, the quartz sand offers a protection to the attached MS2 against inactivation. Moreover, in most cases similar inactivation rates were observed in reactor and control tubes (absence of TiO2 NPs) suggesting that low TiO2 concentration (10 mg/L) affects only slightly MS2 inactivation with and without ambient light.
Japanese children's family drawings and their link to attachment.

PubMed

Behrens, Kazuko Y; Kaplan, Nancy

2011-09-01

This study explored the applicability of family drawings as a tool to estimate attachment security in a sample of Japanese six-year-olds (N = 47), applying Kaplan and Main's ( 1986 ) Family Drawing system. Maternal secure/insecure attachment status judged by the Adult Attachment Interview predicted family drawings' secure/insecure distinction produced by Japanese six-year-olds. However, insecure Japanese drawings took forms not seen in the original Berkeley drawings, such as a lineup of faces alone. Further examination of the Japanese children's drawings using global rating scales (Fury, Carlson, & Sroufe, 1997 ) yielded significant gender differences, rarely reported in the attachment literature, with girls scoring higher in scales that predict attachment security and boys scoring higher in scales that predict attachment insecurity. However, attachment security, as captured in the drawings, was not related to attachment security, observed behaviorally using Main and Cassidy's ( 1988 ) sixth-year reunion system. Implications of the findings are discussed in light of measurements, gender, and culture.
Adult attachment, hostile conflict, and relationship adjustment among couples facing multiple sclerosis.

PubMed

Crangle, Cassandra J; Hart, Tae L

2017-11-01

Couples facing multiple sclerosis (MS) report significantly elevated rates of relationship distress, yet the effects of attachment have never been examined in this population. We examined whether hostile conflict mediated the dyadic effects of attachment on relationship adjustment in couples facing MS and whether these associations were moderated by gender or role. We also explored whether dyadic adjustment mediated the relationship between attachment and hostile conflict. The study was cross-sectional and included 103 couples in which one partner had been diagnosed with MS. Participants completed the Experiences in Close Relationships-Revised, Dyadic Adjustment Scale, and Aversive Interactions Scale, as well as demographic variables. We used the actor-partner interdependence model for data analysis. There were significant actor and partner effects of greater anxious attachment and worse dyadic adjustment. Actor and partner effects of anxious attachment were significantly mediated by greater hostile conflict. Gender significantly moderated the effects between avoidant attachment and dyadic adjustment. The actor effect was significant for males and females; the partner effect was only significant for females. The actor effect for females but not males was significantly mediated by greater hostile conflict. Role was not a significant moderator. Exploratory analyses also showed that dyadic adjustment mediated the relationship between anxious and avoidant attachment and hostile conflict. Findings highlight the important effects of attachment on relationship adjustment in MS couples. Both hostile conflict and dyadic adjustment appear to be mechanisms through which insecure attachment has a detrimental effect. Statement of contribution What is already known on this subject? Despite higher-than-normal rates of marital distress and separation/divorce, the effects of attachment on relationship adjustment among couples facing multiple sclerosis have never been examined. Prior studies within healthy populations have supported within-person and cross-dyadic associations between attachment and relationship adjustment; however, they have failed to use dyadic analyses. Hostile conflict has been associated with both insecure attachment and relationship adjustment and therefore may be an important mediator to help understand these relationships. What does this study add? Women were more negatively affected by their partner's avoidant attachment then men. Hostile conflict mediated the effects of anxious attachment on dyadic adjustment for individuals and across dyads. Hostile conflict accounted for the individual effect of avoidant attachment on dyadic adjustment for women. © 2017 The British Psychological Society.
[The influencing factors on alienation in high school students].

PubMed

Lee, Eun-Sook

2004-02-01

This study was performed to identify the influencing factors on alienation among high school students. Data was collected by questionnaires from 550 students of academic and vocational high schools in G city. The data was analyzed using descriptive statistics, pearson correlation coefficients, and stepwise multiple regression. The scores of alienation among students in financially lower middle class and lower class were higher than those of the upper middle class students, resulting in significant differences(F=6.87, p=.00). A sense of alienation showed a significantly negative correlation with the scores of responding parenting style(r=-.32), family cohesion(r=-.33), school attachment(r=-.51), academic performance(r=-.34), peer relationships(r=-.38), self-control (r=-.43), and social skills(r=-.33). The most powerful predictor of alienation among high school students was school attachment and the variance explained was 26%. A combination of school attachment, self control, peer relationships, family cohesion, demanding parenting style, and academic performance account for 40% of the variance in alienation among high school students. This study suggests that school attachment, self control, peer relationships, family cohesion, demanding parenting style, and academic performance are significant influencing factors on alienation in high school students. Therefore, nursing strategy is needed to manage these revealed factors.
An innovative approach to attached cultivation of Chlorella vulgaris using different materials.

PubMed

Jafari, Negar; Shafiee Alavijeh, Razieh; Abdolahnejad, Ali; Farrokhzadeh, Hossein; Amin, Mohammad Mehdi; Ebrahimi, Afshin

2018-05-10

This article investigates the innovative attached cultivation of Chlorella vulgaris (C. vulgaris) using different materials as an alternative to high capital techniques of harvesting such as centrifugation, flocculation, and filtration. A simple attached algal cultivation system was proposed that was equipped by 10 submerged supporting materials which can harvest algal cells, efficiently. The effect of operational parameters such as light intensity, the rate of aeration, and auto-harvesting time was investigated. A chip, durable, and abundant cellulosic material (Kaldnes carriers covered by kenafs, KCCKs) was proposed for auto-harvesting C. vulgaris cells. The results revealed that optimum aeration rate, light intensity, and auto-harvesting of microalgal cells were 3.6 vvm, 10,548 W/m 2 , and 12 days, respectively. Six of these KCCKs had the highest biofilm formation percent up to 33%. In this condition, the rate of cell growth increased to 0.6 mg/cm 2 . Therefore, this system can be used for appropriate auto-harvesting of microalgae in the attached growth systems. C. vulgaris biomass composition is valuable for biodiesel, bioethanol, and animal protein production.
Ceramic blade with tip seal

DOEpatents

Glezer, B.; Bhardwaj, N.K.; Jones, R.B.

1997-08-05

The present gas turbine engine includes a disc assembly defining a disc having a plurality of blades attached thereto. The disc has a preestablished rate of thermal expansion and the plurality of blades have a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the disc. A shroud assembly is attached to the gas turbine engine and is spaced from the plurality of blades a preestablished distance forming an interface there between. Positioned in the interface is a seal having a preestablished rate of thermal expansion being generally equal to the rate of thermal expansion of the plurality of blades. 4 figs.
Combining CFD simulations with blockoriented heatflow-network model for prediction of photovoltaic energy-production

NASA Astrophysics Data System (ADS)

Haber, I. E.; Farkas, I.

2011-01-01

The exterior factors which influencing the working circumstances of photovoltaic modules are the irradiation, the optical air layer (Air Mass - AM), the irradiation angle, the environmental temperature and the cooling effect of the wind. The efficiency of photovoltaic (PV) devices is inversely proportional to the cell temperature and therefore the mounting of the PV modules can have a big affect on the cooling, due to wind flow-around and naturally convection. The construction of the modules could be described by a heatflow-network model, and that can define the equation which determines the cells temperature. An equation like this can be solved as a block oriented model with hybrid-analogue simulator such as Matlab-Simulink. In view of the flow field and the heat transfer, witch was calculated numerically, the heat transfer coefficients can be determined. Five inflow rates were set up for both pitched and flat roof cases, to let the trend of the heat transfer coefficient know, while these functions can be used for the Matlab/Simulink model. To model the free convection flows, the Boussinesq-approximation were used, integrated into the Navier-Stokes equations and the energy equation. It has been found that under a constant solar heat gain, the air velocity around the modules and behind the pitched-roof mounted module is increasing, proportionately to the wind velocities, and as result the heat transfer coefficient increases linearly, and can be described by a function in both cases. To the block based model the meteorological parameters and the results of the CFD simulations as single functions were attached. The final aim was to make a model that could be used for planning photovoltaic systems, and define their accurate performance for better sizing of an array of modules.
In-situ kinetics study on the growth of expanded austenite in AISI 316L stainless steels by XRD

NASA Astrophysics Data System (ADS)

Balogh-Michels, Zoltán; Faeht, Alexander; Kleiner, Simon; von Känel, Adrian; Rufer, Jean-Martin; Dommann, Alex; Margraf, Patrick; Tschopp, Gerhard; Neels, Antonia

2017-07-01

The formation of expanded austenite in Cr-Ni austenitic stainless steels like AISI 316L is not completely understood despite its technological relevance. In this work, we present an in-situ X-ray diffraction study on the growth kinetics of the expanded austenite. We applied a low-temperature nitrocarburizing treatment using a mixture of NH3, N2, H2, and C2H4 gases at atmospheric pressures in a novel and custom built chamber attached to a Bruker D8 Advance diffractometer. The nitrocarburizing temperature was varied between 340 and 440 °C, and the possible effects of the gas amount were also tested. The thickness of the growing layer was determined from the shrinkage of the unmodified austenite peak. The growth rate coefficient was calculated using the linear-parabolic equation. The resulting coefficients follow the Arrhenius law with the activation energy of 165 ± 12 kJ/mol. This value is in good agreement with the diffusion activation energy for heavy interstitials like carbon and nitrogen. The expanded austenite peak was modelled by a multilayer approach, where each 0.5 μm sublayer has a constant lattice parameter. The lattice expansion is analyzed as a function of the Boltzmann-variable (η = 0.5 × t-1/2). The expanded austenite layer in this metric has a constant width. Furthermore by rescaling with the lattice expansion of the first sublayer, it is possible to create a scale-independent master curve. These findings indicate that thickening of the expanded austenite is purely diffusion controlled, while the extent of strain is set by the uptake rate of the gas atoms.
Rapid evaluation for dielectronic recombination rate coefficients of the H-like isoelectronic sequence.

NASA Astrophysics Data System (ADS)

Teng, H.; Xu, Z.

1996-09-01

The authors present a set of accurate formulae for the rapid calculation of dielectronic recombination rate coefficients of H-like ions from Ne (Z = 10) to Ni (Z = 29) with an electron temperature range from 0.6 to 10 keV. This set of formulae are obtained by fitting directly the dielectronic recombination rate coefficients calculated on the basis of the intermediate - coupling multi - configuration Hartree-Fock model made by Karim and Bhalla (1988). The dielectronic recombination rate coefficients from these formulae are in close agreement with the original results of Karim et al. The errors are generally less than 0.1%. The results are also compared with the ones obtained by a set of new rate formulae developed by Hahn. These formulae can be used for generating dielectronic recombination rate coefficients of some H-like ions where the explicit calculations are unavailable. The detailed results are tabulated and discussed.
[Observation of Attachment Disorder Symptoms in Middle Childhood].

PubMed

Iwanski, Alexandra; Zimmermann, Peter

2018-05-01

Observation of Attachment Disorder Symptoms in Middle Childhood Attachment in childhood is mainly assessed by observation. In contrast, assessment of attachment disorder symptoms (RAD) is mainly based on caregiver reports. The present study uses a newly developed observation tool (Coding of Attachment Disorder Behavior in Children; Iwanski u. Zimmermann, 2013) to assess attachment disorder symptoms in a group of school-aged children from a risk group for the development of attachment disorder symptoms and non-clinical controls. In addition, caregiver reports on RAD symptoms are also assessed (Relationship Problems Questionnaire; Minnis, Rabe-Hesketh, Wolkind, 2002; Disturbances of Attachment Interview; Smyke u. Zeanah, 1999). Moreover, associations with children's self-concept (Harter, 2012) were studied. Results reveal that children at risk showed more inhibited and disinhibited attachment disorder symptoms and a more negative self-concept compared to non-clinical controls. RAD symptoms are shown in interaction with both the caregiver and a stranger. The use of a reliable and valid observation tool for the diagnostic of attachment disorder symptoms besides ratings of caregivers is recommended for clinical practice and research.
Development of a Plantar Load Estimation Algorithm for Evaluation of Forefoot Load of Diabetic Patients during Daily Walks Using a Foot Motion Sensor

PubMed Central

Noguchi, Hiroshi; Sanada, Hiromi

2017-01-01

Forefoot load (FL) contributes to callus formation, which is one of the pathways to diabetic foot ulcers (DFU). In this study, we hypothesized that excessive FL, which cannot be detected by plantar load measurements within laboratory settings, occurs in daily walks. To demonstrate this, we created a FL estimation algorithm using foot motion data. Acceleration and angular velocity data were obtained from a motion sensor attached to each shoe of the subjects. The accuracy of the estimated FL was validated by correlation with the FL measured by force sensors on the metatarsal heads, which was assessed using the Pearson correlation coefficient. The mean of correlation coefficients of all the subjects was 0.63 at a level corridor, while it showed an intersubject difference at a slope and stairs. We conducted daily walk measurements in two diabetic patients, and additionally, we verified the safety of daily walk measurement using a wearable motion sensor attached to each shoe. We found that excessive FL occurred during their daily walks for approximately three hours in total, when any adverse event was not observed. This study indicated that FL evaluation method using wearable motion sensors was one of the promising ways to prevent DFUs. PMID:28840130
Cable vibration control with both lateral and rotational dampers attached at an intermediate location

NASA Astrophysics Data System (ADS)

Chen, Lin; Sun, Limin; Nagarajaiah, Satish

2016-09-01

Lateral dampers have been extensively studied and implemented for supplementing modal damping in cable vibration mitigation. When considering the cable flexural stiffness that is actually present, albeit small, there is another degree of freedom of the cable at the lateral damper, namely the rotation, that can be constrained by a rotational damper to achieve larger additional damping. This is of particular significance for long cables where the near-anchorage lateral damper alone is usually insufficient. The problem of a cable with bending stiffness, attached with both lateral and rotational dampers at an intermediate point, is therefore considered in this study. The characteristic equation of the resulting system is formulated by assembling the dynamic stiffness from the two segments divided by the damper, which is subsequently solved using argument principle method. Dynamics of the controlled system is thus discussed in general through parametric analysis. For the case where the damper location is close to the anchorage, asymptotic solutions for complex frequency and damping ratio are provided; explicit formulas for determining the optimal damper coefficients are also derived. It is found that when the lateral and rotational damper coefficients are properly balanced, the proposed strategy can achieve up to 30 percent damping enhancement compared to the case with only the lateral damper, in practical cable bending stiffness range.
Development of a Plantar Load Estimation Algorithm for Evaluation of Forefoot Load of Diabetic Patients during Daily Walks Using a Foot Motion Sensor.

PubMed

Watanabe, Ayano; Noguchi, Hiroshi; Oe, Makoto; Sanada, Hiromi; Mori, Taketoshi

2017-01-01

Forefoot load (FL) contributes to callus formation, which is one of the pathways to diabetic foot ulcers (DFU). In this study, we hypothesized that excessive FL, which cannot be detected by plantar load measurements within laboratory settings, occurs in daily walks. To demonstrate this, we created a FL estimation algorithm using foot motion data. Acceleration and angular velocity data were obtained from a motion sensor attached to each shoe of the subjects. The accuracy of the estimated FL was validated by correlation with the FL measured by force sensors on the metatarsal heads, which was assessed using the Pearson correlation coefficient. The mean of correlation coefficients of all the subjects was 0.63 at a level corridor, while it showed an intersubject difference at a slope and stairs. We conducted daily walk measurements in two diabetic patients, and additionally, we verified the safety of daily walk measurement using a wearable motion sensor attached to each shoe. We found that excessive FL occurred during their daily walks for approximately three hours in total, when any adverse event was not observed. This study indicated that FL evaluation method using wearable motion sensors was one of the promising ways to prevent DFUs.
Attachment security as a mechanism linking foster care placement to improved mental health outcomes in previously institutionalized children

PubMed Central

McLaughlin, Katie A.; Zeanah, Charles H.; Fox, Nathan A.; Nelson, Charles A.

2011-01-01

Background Children reared in institutions experience elevated rates of psychiatric disorders. Inability to form a secure attachment relationship to a primary caregiver is posited to be a central mechanism in this association. We determined whether the ameliorative effect of a foster care (FC) intervention on internalizing disorders in previously institutionalized children was explained by the development of secure attachment among children placed in FC and evaluated the role of lack of attachment in an institutionalized sample on the etiology of internalizing disorders within the context of a randomized trial. Methods A sample of 136 children (aged 6-30 months) residing in institutions was recruited in Bucharest, Romania. Children were randomized to FC (n=68) or to care as usual (CAU; n=68). Foster parents were recruited, trained, and overseen by the investigative team. Attachment security at 42 months was assessed using the Strange Situation Procedure, and internalizing disorders at 54 months were assessed using the Preschool Age Psychiatric Assessment. Results Girls in FC had fewer internalizing disorders than girls in CAU (OR=0.17, p=006). The intervention had no effect on internalizing disorders in boys (OR=0.47, p=.150). At 42 months, girls in FC were more likely to have secure attachment than girls in CAU (OR=12.5, p<.001), but no difference was observed in boys (OR=2.0, p=.205). Greater attachment security predicted lower rates of internalizing disorders in both sexes. Development of attachment security fully mediated intervention effects on internalizing disorders in girls. Conclusion Placement into FC facilitated the development of secure attachment and prevented the onset of internalizing disorders in institutionalized girls. The differential effects of FC on attachment security in boys and girls explained gender differences in the intervention effects on psychopathology. Findings provide evidence for the critical role of disrupted attachment in the etiology of internalizing disorders in children exposed to institutionalization. PMID:21733136

Fretting Stresses in Single Crystal Superalloy Turbine Blade Attachments

NASA Technical Reports Server (NTRS)

Arakere, Nagaraj K.; Swanson, Gregory

2000-01-01

Single crystal nickel base superalloy turbine blades are being utilized in rocket engine turbopumps and turbine engines because of their superior creep, stress rupture, melt resistance and thermomechanical fatigue capabilities over polycrystalline alloys. Currently the most widely used single crystal nickel base turbine blade superalloys are PWA 1480/1493 and PWA 1484. These alloys play an important role in commercial, military and space propulsion systems. High Cycle Fatigue (HCF) induced failures in aircraft gas turbine and rocket engine turbopump blades is a pervasive problem. Blade attachment regions are prone to fretting fatigue failures. Single crystal nickel base superalloy turbine blades are especially prone to fretting damage because the subsurface shear stresses induced by fretting action at the attachment regions can result in crystallographic initiation and crack growth along octahedral planes. Furthermore, crystallographic crack growth on octahedral planes under fretting induced mixed mode loading can be an order of magnitude faster than under pure mode I loading. This paper presents contact stress evaluation in the attachment region for single crystal turbine blades used in the NASA alternate Advanced High Pressure Fuel Turbo Pump (HPFTP/AT) for the Space Shuttle Main Engine (SSME). Single crystal materials have highly orthotropic properties making the position of the crystal lattice relative to the part geometry a significant factor in the overall analysis. Blades and the attachment region are modeled using a large-scale 3D finite element (FE) model capable of accounting for contact friction, material orthotrophy, and variation in primary and secondary crystal orientation. Contact stress analysis in the blade attachment regions is presented as a function of coefficient of friction and primary and secondary crystal orientation, Stress results are used to discuss fretting fatigue failure analysis of SSME blades. Attachment stresses are seen to reach peak values at locations where fretting cracks have been observed. Fretting stresses at the attachment region are seen to vary significantly as a function of crystal orientation. Attempts to adapt techniques used for estimating fatigue life in the airfoil region, for life calculations in the attachment region, are presented. An effective model for predicting crystallographic crack initiation under mixed mode loading is required for life prediction under fretting action.
Familiarity breeds respect: attitudes of medical students towards psychiatry following a clinical attachment.

PubMed

Lampe, Lisa; Coulston, Carissa; Walter, Garry; Malhi, Gin

2010-08-01

The aim of this paper was to examine the influence of a clinical attachment in psychiatry on medical students' attitudes to psychiatry as a specialty and potential career. Medical students at Sydney Medical School were surveyed following an 8-week clinical attachment in psychiatry. Secondary analyses sought to identify associations with variables such as age, gender and level of clinical experience as a medical student. Following a clinical attachment in psychiatry, 80% of students rated their attitude to psychiatry as more positive. Approximately 32% rated themselves as likely or very likely to choose a career in psychiatry. No differences were seen with respect to gender, age or stage of training. The quality of the teaching, enthusiasm of the clinical teachers, the holistic approach and scientific basis of psychiatry were cited by students as factors influencing attitudes. The clinical rotation in psychiatry is a significant factor influencing medical student attitudes towards psychiatry.
Congruence between Spouses’ Perceptions and Observers’ Ratings of Responsiveness: The Role of Attachment Avoidance

PubMed Central

Beck, Lindsey A.; Pietromonaco, Paula R.; DeVito, Cassandra C.; Powers, Sally I.; Boyle, Alysia M.

2016-01-01

Although close relationships require partners to depend on one another for mutual responsiveness, avoidantly-attached individuals are especially averse to risking such dependency. The authors propose that both avoidant and non-avoidant individuals perceive signs of their own and their partners’ responsiveness in ways that reflect motivated perceptions of dependency. The present research examined how the interplay between spouses’ attachment avoidance and observed responsive behaviors during marital conflict shaped perceptions of their own and their partners’ responsiveness. Newlywed couples attempted to resolve a relationship conflict, then reported perceptions of their own and their partners’ responsiveness during the conflict. Observers also coded both partners’ responsive behaviors during the conflict. Avoidant husbands perceived themselves as less responsive than did observers; avoidant wives’ perceptions that their husbands were less responsive matched observers’ ratings. The discussion highlights the role of gender role norms in understanding links between attachment and responsiveness. PMID:24132245
Convergence of damped inertial dynamics governed by regularized maximally monotone operators

NASA Astrophysics Data System (ADS)

Attouch, Hedy; Cabot, Alexandre

2018-06-01

In a Hilbert space setting, we study the asymptotic behavior, as time t goes to infinity, of the trajectories of a second-order differential equation governed by the Yosida regularization of a maximally monotone operator with time-varying positive index λ (t). The dissipative and convergence properties are attached to the presence of a viscous damping term with positive coefficient γ (t). A suitable tuning of the parameters γ (t) and λ (t) makes it possible to prove the weak convergence of the trajectories towards zeros of the operator. When the operator is the subdifferential of a closed convex proper function, we estimate the rate of convergence of the values. These results are in line with the recent articles by Attouch-Cabot [3], and Attouch-Peypouquet [8]. In this last paper, the authors considered the case γ (t) = α/t, which is naturally linked to Nesterov's accelerated method. We unify, and often improve the results already present in the literature.
Evidence of atmospheric gravity wave perturbations of the Brunt-Vaisala frequency in the atmosphere

NASA Technical Reports Server (NTRS)

Good, R. E.; Beland, R. W.; Brown, J. H.; Dewan, E. M.

1986-01-01

A series of high altitude, medium resolution, measurements of temperature, pressure and turbulence have been performed by the Air Force Geophysics Laboratory. These measurements were conducted using the VIZ Manufacturing Co. microsondes with attached micro-thermal probes measuring the temperature structure coefficient. A typical atmospheric temperature measurement is given. Several small temperature inversions are evident in the troposphere. The stratosphere is marked with numerous fluctuations in the temperature profile. Microsondes provide temperature and pressure measurements every 4 seconds up to a maximum altitude of 30 km (MSL). Since the average ascent rate is 5 m/s, the altitude interval between the measurement reports is 20 m. The potential temperature is calculated from the temperature and pressure. Spectral analysis of atmospheric Brunt-Vaisala frequencies reveal spectra similiar to the velocity spectra of Dewan et al. (1984), Daniels (1982), and Endlich and Singleton (1969). The Brunt-Vaisala spectra indicate the existence of separate, distinguishable wave modes.
Stress Intensity of Delamination in a Sintered-Silver Interconnection: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeVoto, D. J.; Paret, P. P.; Wereszczak, A. A.

2014-08-01

In automotive power electronics packages, conventional thermal interface materials such as greases, gels, and phase-change materials pose bottlenecks to heat removal and are also associated with reliability concerns. The industry trend is toward high thermal performance bonded interfaces for large-area attachments. However, because of coefficient of thermal expansion mismatches between materials/layers and resultant thermomechanical stresses, adhesive and cohesive fractures could occur, posing a reliability problem. These defects manifest themselves in increased thermal resistance. This research aims to investigate and improve the thermal performance and reliability of sintered-silver for power electronics packaging applications. This has been experimentally accomplished by the synthesismore » of large-area bonded interfaces between metalized substrates and copper base plates that have subsequently been subjected to thermal cycles. A finite element model of crack initiation and propagation in these bonded interfaces will allow for the interpretation of degradation rates by a crack-velocity (V)-stress intensity factor (K) analysis. A description of the experiment and the modeling approach are discussed.« less
A far-red fluorescent protein evolved from a cyanobacterial phycobiliprotein

PubMed Central

Rodriguez, Erik A.; Tran, Geraldine N.; Gross, Larry A.; Crisp, Jessica L.; Shu, Xiaokun; Lin, John Y.; Tsien, Roger Y.

2016-01-01

Far-red fluorescent proteins (FPs) are desirable for in vivo imaging because less light is scattered, absorbed, or reemitted by endogenous biomolecules. A new class of FP was developed from an allophycocyanin α-subunit (APCα). Native APC requires a lyase to incorporate phycocyanobilin. The evolved FP, named small Ultra-Red FP (smURFP), covalently attaches biliverdin (BV) without a lyase, and has 642/670 nm excitation/emission peaks, a large extinction coefficient (180,000 M−1cm−1) and quantum yield (18%), and comparable photostability to eGFP. SmURFP has significantly increased BV incorporation rate and protein stability compared to the bacteriophytochrome (BPH) FPs. BV supply is limited by membrane permeability, so expression of heme oxygenase-1 with heme precursors increases fluorescence of BPH/APCα FPs. SmURFP (but not BPH FPs) can incorporate a more membrane-permeant BV analog, making smURFP fluorescence in situ comparable to FPs from jellyfish/coral. A far-red/near-infrared fluorescent cell cycle indicator was created with smURFP and a BPH FP. PMID:27479328
Attachment and group psychotherapy: introduction to a special section.

PubMed

Tasca, Giorgio A

2014-03-01

The application of attachment theory to adult psychotherapy represents a growing area of research and practice. Despite the conceptual overlap between group therapeutic factors, attachment theory, and therapeutic tasks as outlined by Bowlby (1988), there is little research on attachment functioning in group therapy. Hence, there remain substantial questions about the role of attachment theory in understanding group therapy processes and outcomes. The three studies in this special section advance the research in some of these important areas, including showing that positive changes in self-reported attachment insecurity among clients persist long after group therapy ends; attachment anxiety affects the level and rate of interpersonal learning in groups; and change in attachment to the therapy group has an impact on longer term change in individual group members' attachment. Each article also examines the impact of these attachment concepts on treatment outcomes. Numerous areas remain to be explored when it comes to the implications of attachment theory for understanding and conducting group therapy, including the conceptual and practical overlap between attachment concepts such as security and exploration with group therapeutic factors such as cohesion and interpersonal learning. The articles in this special section begin to address some of these issues related to attachment theory and its implications for group therapists. (c) 2014 APA, all rights reserved.
VizieR Online Data Catalog: Rate coefficients for H2(v,j)+H2(v',j'

NASA Astrophysics Data System (ADS)

Mandy, M. E.

2016-11-01

State-specific rate coefficients for the dissociation of H2 result of collisions with H2 were calculated for all combinations of (v,j) with an internal energy below 1eV. Full-dimensional quasiclassical trajectories were calculated using the BMKP2 interaction potential with a minimum of 80000 trajectories at each translational energy. Additional large batches of trajectories were carried out to calculate the cross sections near the threshold to dissociation to attain the desired precision of the rate coefficients. A piecewise linear excitation function was used to calculate the rate coefficient between 100 and 100000K. The resulting state-specific rate coefficients, γ, were parametrized as a function of temperature over the range 600-10000K using: log10γ(t)=a+bz+cz2-d(1/t-1) where t=T/4500K and z=log10t. The values of the resulting rate coefficients were sensitive to the internal energy of both molecules, with initial vibrational energy having a slightly greater effect than rotational energy. This effect diminished as temperature increased. (15 data files).
A study of the liquid-vapor phase change of mercury based on irreversible thermodynamics.

NASA Technical Reports Server (NTRS)

Adt, R. R., Jr.; Hatsopoulos, G. N.; Bornhorst, W. J.

1972-01-01

The object of this work is to determine the transport coefficients which appear in linear irreversible-thermodynamic rate equations of a phase change. An experiment which involves the steady-state evaporation of mercury was performed to measure the principal transport coefficient appearing in the mass-rate equation and the coupling transport coefficient appearing in both the mass-rate equation and the energy-rate equation. The principal transport coefficient sigma, usually termed the 'condensation' or 'evaporation' coefficient, is found to be approximately 0.9, which is higher than that measured previously in condensation-of-mercury experiments. The experimental value of the coupling coefficient K does not agree with the value predicted from Schrage's kinetic analysis of the phase change. A modified kinetic analysis in which the Onsager reciprocal law and the conservation laws are invoked is presented which removes this discrepancy but which shows that the use of Schrage's equation for predicting mass rates of phase change is a good approximation.
Modeling Aggregation Processes of Lennard-Jones particles Via Stochastic Networks

NASA Astrophysics Data System (ADS)

Forman, Yakir; Cameron, Maria

2017-07-01

We model an isothermal aggregation process of particles/atoms interacting according to the Lennard-Jones pair potential by mapping the energy landscapes of each cluster size N onto stochastic networks, computing transition probabilities from the network for an N-particle cluster to the one for N+1, and connecting these networks into a single joint network. The attachment rate is a control parameter. The resulting network representing the aggregation of up to 14 particles contains 6427 vertices. It is not only time-irreversible but also reducible. To analyze its transient dynamics, we introduce the sequence of the expected initial and pre-attachment distributions and compute them for a wide range of attachment rates and three values of temperature. As a result, we find the configurations most likely to be observed in the process of aggregation for each cluster size. We examine the attachment process and conduct a structural analysis of the sets of local energy minima for every cluster size. We show that both processes taking place in the network, attachment and relaxation, lead to the dominance of icosahedral packing in small (up to 14 atom) clusters.
Computed rate coefficients and product yields for c-C5H5 + CH3 --> products.

PubMed

Sharma, Sandeep; Green, William H

2009-08-06

Using quantum chemical methods, we have explored the region of the C6H8 potential energy surface that is relevant in predicting the rate coefficients of various wells and major product channels following the reaction between cyclopentadienyl radical and methyl radical, c-C5H5 + CH3. Variational transition state theory is used to calculate the high-pressure-limit rate coefficient for all of the barrierless reactions. RRKM theory and the master equation are used to calculate the pressure dependent rate coefficients for 12 reactions. The calculated results are compared with the limited experimental data available in the literature and the agreement between the two is quite good. All of the rate coefficients calculated in this work are tabulated and can be used in building detailed chemical kinetic models.
Hyperfine excitation of C2H in collisions with ortho- and para-H2

NASA Astrophysics Data System (ADS)

Dagdigian, Paul J.

2018-06-01

Accurate estimation of the abundance of the ethynyl (C2H) radical requires accurate radiative and collisional rate coefficients. Hyperfine-resolved rate coefficients for (de-)excitation of C2H in collisions with ortho- and para-H2 are presented in this work. These rate coefficients were computed in time-independent close-coupling quantum scattering calculations that employed a potential energy surface recently computed at the coupled-clusters level of theory that describes the interaction of C2H with H2. Rate coefficients for temperatures from 10 to 300 K were computed for all transitions among the first 40 hyperfine energy levels of C2H in collisions with ortho- and para-H2. These rate coefficients were employed in simple radiative transfer calculations to simulate the excitation of C2H in typical molecular clouds.
Rate Coefficient Measurements of the Reaction CH3+O2+CH3O+O

NASA Technical Reports Server (NTRS)

Hwang, S. M.; Ryu, Si-Ok; DeWitt, K. J.; Rabinowitz, M. J.

1999-01-01

Rate coefficients for the reaction CH3 + O2 = CH3O + O were measured behind reflected shock waves in a series of lean CH4-O2-Ar mixtures using hydroxyl and methyl radical diagnostics. The rate coefficients are well represented by an Arrhenius expression given as k = (1.60(sup +0.67, -0.47)) X 10(exp 13) exp(- 15813 +/- 587 K/T)cc/mol s. This expression, which is valid in the temperature range 1575-1822 K, supports the downward trend in the rate coefficients that has been reported in recent determinations. All measurements to date, including the present study, have been to some extent affected by secondary reactions. The complications due to secondary reactions, choice of thermochemical data, and shock-boundary layer interactions that affect the determination of the rate coefficients are examined.
Relationships between self-reported childhood traumatic experiences, attachment style, neuroticism and features of borderline personality disorders in patients with mood disorders.

PubMed

Baryshnikov, Ilya; Joffe, Grigori; Koivisto, Maaria; Melartin, Tarja; Aaltonen, Kari; Suominen, Kirsi; Rosenström, Tom; Näätänen, Petri; Karpov, Boris; Heikkinen, Martti; Isometsä, Erkki

2017-03-01

Co-occurring borderline personality disorder (BPD) features have a marked impact on treatment of patients with mood disorders. Overall, high neuroticism, childhood traumatic experiences (TEs) and insecure attachment are plausible aetiological factors for BPD. However, their relationship with BPD features specifically among patients with mood disorders remains unclear. We investigated these relationships among unipolar and bipolar mood disorder patients. As part of the Helsinki University Psychiatric Consortium study, the McLean Screening Instrument (MSI), the Experiences in Close Relationships-Revised (ECR-R), the Short Five (S5) and the Trauma and Distress Scale (TADS) were filled in by patients with mood disorders (n=282) in psychiatric care. Correlation coefficients between total scores of scales and their dimensions were estimated, and multivariate regression (MRA) and mediation analyses were conducted. Spearman's correlations were strong (rho=0.58; p<0.001) between total scores of MSI and S5 Neuroticism and moderate (rho=0.42; p<0.001) between MSI and TADS as well as between MSI and ECR-R Attachment Anxiety. In MRA, young age, S5 Neuroticism and TADS predicted scores of MSI (p<0.001). ECR-R Attachment Anxiety mediated 33% (CI=17-53%) of the relationships between TADS and MSI. Cross-sectional questionnaire study. We found moderately strong correlations between self-reported BPD features and concurrent high neuroticism, reported childhood traumatic experiences and Attachment Anxiety also among patients with mood disorders. Independent predictors for BPD features include young age, frequency of childhood traumatic experiences and high neuroticism. Insecure attachment may partially mediate the relationship between childhood traumatic experiences and borderline features among mood disorder patients. Copyright © 2016 Elsevier B.V. All rights reserved.
Determination of acoustic properties of thin polymer films utilizing the frequency dependence of the reflection coefficient of ultrasound.

PubMed

Tohmyoh, Hironori; Sakamoto, Yuhei

2015-11-01

This paper reports on a technique to measure the acoustic properties of a thin polymer film utilizing the frequency dependence of the reflection coefficient of ultrasound reflected back from a system comprising a reflection plate, the film, and a material that covers the film. The frequency components of the echo reflected from the back of the plate, where the film is attached, take their minimum values at the resonant frequency, and from these frequency characteristics, the acoustic impedance, sound velocity, and the density of the film can be determined. We applied this technique to characterize an ion exchange membrane, which has high water absorbability, and successfully determined the acoustic properties of the membrane without getting it wet.
Organ and effective dose rate coefficients for submersion exposure in occupational settings

DOE PAGES

Veinot, K. G.; Y-12 National Security Complex, Oak Ridge, TN; Dewji, S. A.; ...

2017-08-24

External dose coefficients for environmental exposure scenarios are often computed using assumption on infinite or semi-infinite radiation sources. For example, in the case of a person standing on contaminated ground, the source is assumed to be distributed at a given depth (or between various depths) and extending outwards to an essentially infinite distance. In the case of exposure to contaminated air, the person is modeled as standing within a cloud of infinite, or semi-infinite, source distribution. However, these scenarios do not mimic common workplace environments where scatter off walls and ceilings may significantly alter the energy spectrum and dose coefficients.more » In this study, dose rate coefficients were calculated using the International Commission on Radiological Protection (ICRP) reference voxel phantoms positioned in rooms of three sizes representing an office, laboratory, and warehouse. For each room size calculations using the reference phantoms were performed for photons, electrons, and positrons as the source particles to derive mono-energetic dose rate coefficients. Since the voxel phantoms lack the resolution to perform dose calculations at the sensitive depth for the skin, a mathematical phantom was developed and calculations were performed in each room size with the three source particle types. Coefficients for the noble gas radionuclides of ICRP Publication 107 (e.g., Ne, Ar, Kr, Xe, and Rn) were generated by folding the corresponding photon, electron, and positron emissions over the mono-energetic dose rate coefficients. Finally, results indicate that the smaller room sizes have a significant impact on the dose rate per unit air concentration compared to the semi-infinite cloud case. For example, for Kr-85 the warehouse dose rate coefficient is 7% higher than the office dose rate coefficient while it is 71% higher for Xe-133.« less
Organ and effective dose rate coefficients for submersion exposure in occupational settings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veinot, K. G.; Y-12 National Security Complex, Oak Ridge, TN; Dewji, S. A.

External dose coefficients for environmental exposure scenarios are often computed using assumption on infinite or semi-infinite radiation sources. For example, in the case of a person standing on contaminated ground, the source is assumed to be distributed at a given depth (or between various depths) and extending outwards to an essentially infinite distance. In the case of exposure to contaminated air, the person is modeled as standing within a cloud of infinite, or semi-infinite, source distribution. However, these scenarios do not mimic common workplace environments where scatter off walls and ceilings may significantly alter the energy spectrum and dose coefficients.more » In this study, dose rate coefficients were calculated using the International Commission on Radiological Protection (ICRP) reference voxel phantoms positioned in rooms of three sizes representing an office, laboratory, and warehouse. For each room size calculations using the reference phantoms were performed for photons, electrons, and positrons as the source particles to derive mono-energetic dose rate coefficients. Since the voxel phantoms lack the resolution to perform dose calculations at the sensitive depth for the skin, a mathematical phantom was developed and calculations were performed in each room size with the three source particle types. Coefficients for the noble gas radionuclides of ICRP Publication 107 (e.g., Ne, Ar, Kr, Xe, and Rn) were generated by folding the corresponding photon, electron, and positron emissions over the mono-energetic dose rate coefficients. Finally, results indicate that the smaller room sizes have a significant impact on the dose rate per unit air concentration compared to the semi-infinite cloud case. For example, for Kr-85 the warehouse dose rate coefficient is 7% higher than the office dose rate coefficient while it is 71% higher for Xe-133.« less
Attachment classification, psychophysiology and frontal EEG asymmetry across the lifespan: a review

PubMed Central

Gander, Manuela; Buchheim, Anna

2015-01-01

In recent years research on physiological response and frontal electroencephalographic (EEG) asymmetry in different patterns of infant and adult attachment has increased. We review research findings regarding associations between attachment classifications and frontal EEG asymmetry, the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenocortical axis (HPA). Studies indicate that insecure attachment is related to a heightened adrenocortical activity, heart rate and skin conductance in response to stress, which is consistent with the hypothesis that attachment insecurity leads to impaired emotion regulation. Research on frontal EEG asymmetry also shows a clear difference in the emotional arousal between the attachment groups evidenced by specific frontal asymmetry changes. Furthermore, we discuss neurophysiological evidence of attachment organization and present up-to-date findings of EEG-research with adults. Based on the overall patterns of results presented in this article we identify some major areas of interest and directions for future research. PMID:25745393
Hydrothermal atomic force microscopy observations of barite step growth rates as a function of the aqueous barium-to-sulfate ratio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bracco, Jacquelyn N.; Gooijer, Yiscka; Higgins, Steven R.

The rate of growth of ionic minerals from solutions with varying aqueous cation:anion ratios may result in significant errors in mineralization rates predicted by commonly-used affinity-based rate equations. To assess the potential influence of solute stoichiometry on barite growth, step velocities on the barite (001) surface have been measured at 108 °C using hydrothermal atomic force microscopy (HAFM) at moderate supersaturation and as a function of the aqueous barium:sulfate ratio (r). Barite growth hillocks at r ~ 1 were bounded bymore » $$\\langle$$120$$\\rangle$$ steps, however at r < 1, kink site densities increased, steps followed a direction vicinal to $$\\langle$$120$$\\rangle$$, and the [010] steps developed. At r > 1, steps roughened and rounded as the kink site density increased. Step velocities peaked at r = 1 and decreased roughly symmetrically as a function of r, indicating the attachment rates of barium and sulfate ions are similar under these conditions. We hypothesize that the differences in our observations at high and low r arise from differences in the attachment rate constants for the obtuse and acute $$\\langle$$120$$\\rangle$$ steps. Based on results at low r, the data suggests the attachment rate constant for barium ions is similar for obtuse and acute steps. Based on results at high r, the data suggests the attachment rate constant for sulfate is greater for obtuse steps than acute steps. In conclusion, utilizing a step growth model developed by Stack and Grantham (2010) the experimental step velocities as a function of r were readily fit while attempts to fit the data using a model developed by Zhang and Nancollas (1998) were less successful.« less

Hydrothermal atomic force microscopy observations of barite step growth rates as a function of the aqueous barium-to-sulfate ratio

DOE PAGES

Bracco, Jacquelyn N.; Gooijer, Yiscka; Higgins, Steven R.

2016-03-19

The rate of growth of ionic minerals from solutions with varying aqueous cation:anion ratios may result in significant errors in mineralization rates predicted by commonly-used affinity-based rate equations. To assess the potential influence of solute stoichiometry on barite growth, step velocities on the barite (001) surface have been measured at 108 °C using hydrothermal atomic force microscopy (HAFM) at moderate supersaturation and as a function of the aqueous barium:sulfate ratio (r). Barite growth hillocks at r ~ 1 were bounded bymore » $$\\langle$$120$$\\rangle$$ steps, however at r < 1, kink site densities increased, steps followed a direction vicinal to $$\\langle$$120$$\\rangle$$, and the [010] steps developed. At r > 1, steps roughened and rounded as the kink site density increased. Step velocities peaked at r = 1 and decreased roughly symmetrically as a function of r, indicating the attachment rates of barium and sulfate ions are similar under these conditions. We hypothesize that the differences in our observations at high and low r arise from differences in the attachment rate constants for the obtuse and acute $$\\langle$$120$$\\rangle$$ steps. Based on results at low r, the data suggests the attachment rate constant for barium ions is similar for obtuse and acute steps. Based on results at high r, the data suggests the attachment rate constant for sulfate is greater for obtuse steps than acute steps. In conclusion, utilizing a step growth model developed by Stack and Grantham (2010) the experimental step velocities as a function of r were readily fit while attempts to fit the data using a model developed by Zhang and Nancollas (1998) were less successful.« less
MO-AB-BRA-04: Radiation Measurements with a DNA Double-Strand-Break Dosimeter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Obeidat, M; Cline, K; Stathakis, S

Purpose: Many types of dosimeters are used to measure radiation, but none of them directly measures the biological effect of this dose. The purpose here is to create a dosimeter that can measure the probability of double-strand breaks (DSB) for DNA, which is directly related to the biological effect of radiation. Methods: The dosimeter has DNA strands, which are labeled on one end with biotin and on the other with fluorescein. The biotin attaches these strands to magnetic beads. We suspended the DNA dosimeter in phosphate-buffered saline (PBS) as it matches the internal environment of the body. We placed smallmore » volumes (50µL) of the DNA dosimeter into tubes and irradiated these samples in a water-equivalent plastic phantom with several doses (three samples per dose). After irradiating the samples, a magnet was placed against the tubes. The fluorescein attached to broken DNA strands was extracted (called the supernatant) and placed into a different tube. The fluorescein on the unbroken strands remained attached to the beads in the tube and was re-suspended with 50µL of PBS. A fluorescence reader was used to measure the fluorescence for both the re-suspended beads and supernatant. To prove that we are measuring DSB, we tested dosimeter response with two different lengths of attached DNA strands (1 and 4 kilo-base pair). Results: The probability of DSB at the dose levels of 5, 10, 25, and 50 Gy were 0.05, 0.08, 0.12, and 0.19, respectively, while the coefficients of variation were 0.14, 0.07, 0.02, and 0.01, respectively. The 4 kilo-base-pair dosimeter produced 5.3 times the response of the 1 kilo-base-pair dosimeter. Conclusion: The DNA dosimeter yields a measurable response to dose that scales with the DNA strand length. The goal now is to refine the dosimeter fabrication to reproducibly create a low coefficient of variation for the lower doses. This work was supported in part by Yarmouk University (Irbid, Jordan) and CPRIT (RP140105)« less
Resonant structure of low-energy H3+ dissociative recombination

NASA Astrophysics Data System (ADS)

Petrignani, Annemieke; Altevogt, Simon; Berg, Max H.; Bing, Dennis; Grieser, Manfred; Hoffmann, Jens; Jordon-Thaden, Brandon; Krantz, Claude; Mendes, Mario B.; Novotný, Oldřich; Novotny, Steffen; Orlov, Dmitry A.; Repnow, Roland; Sorg, Tobias; Stützel, Julia; Wolf, Andreas; Buhr, Henrik; Kreckel, Holger; Kokoouline, Viatcheslav; Greene, Chris H.

2011-03-01

High-resolution dissociative recombination rate coefficients of rotationally cool and hot H3+ in the vibrational ground state have been measured with a 22-pole trap setup and a Penning ion source, respectively, at the ion storage-ring TSR. The experimental results are compared with theoretical calculations to explore the dependence of the rate coefficient on ion temperature and to study the contributions of different symmetries to probe the rich predicted resonance spectrum. The kinetic energy release was investigated by fragment imaging to derive internal temperatures of the stored parent ions under differing experimental conditions. A systematic experimental assessment of heating effects is performed which, together with a survey of other recent storage-ring data, suggests that the present rotationally cool rate-coefficient measurement was performed at 380-130+50 K and that this is the lowest rotational temperature so far realized in storage-ring rate-coefficient measurements on H3+. This partially supports the theoretical suggestion that temperatures higher than assumed in earlier experiments are the main cause for the large gap between the experimental and the theoretical rate coefficients. For the rotationally hot rate-coefficient measurement a temperature of below 3250 K is derived. From these higher-temperature results it is found that increasing the rotational ion temperature in the calculations cannot fully close the gap between the theoretical and the experimental rate coefficients.
Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

DOE PAGES

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

2018-04-24

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-Molecular Dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients; we use this approach to examine atomic condensation onto 6-56 atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity ( v) between atom and cluster andmore » the initial impact parameter ( b). In all cases there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms, and for 14 atom and 28 atom Mg clusters, as cluster equilibration temperature increases the condensation rate coefficient drops to values below the hard sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (> 1000 m s -1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). In conclusion, the presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.« less
Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations.

PubMed

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J

2018-04-28

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard-sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-molecular dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients. We use this approach to examine atomic condensation onto 6-56-atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity (v) between atom and cluster and the initial impact parameter (b). In all cases, there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard-sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms and for 14- and 28-atom Mg clusters, as cluster equilibration temperature increases, the condensation rate coefficient drops to values below the hard-sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (>1000 m s -1 ) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). The presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.
Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-Molecular Dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients; we use this approach to examine atomic condensation onto 6-56 atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity ( v) between atom and cluster andmore » the initial impact parameter ( b). In all cases there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms, and for 14 atom and 28 atom Mg clusters, as cluster equilibration temperature increases the condensation rate coefficient drops to values below the hard sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (> 1000 m s -1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). In conclusion, the presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.« less
Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

NASA Astrophysics Data System (ADS)

Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

2018-04-01

In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard-sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-molecular dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients. We use this approach to examine atomic condensation onto 6-56-atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity (v) between atom and cluster and the initial impact parameter (b). In all cases, there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard-sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms and for 14- and 28-atom Mg clusters, as cluster equilibration temperature increases, the condensation rate coefficient drops to values below the hard-sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (>1000 m s-1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). The presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.
Negative childhood experiences and adult love relationships: the role of internal working models of attachment.

PubMed

McCarthy, Gerard; Maughan, Barbara

2010-09-01

This study investigated links between internal working models of attachment and the quality of adult love relationships in a high risk sample of women (n = 34), all of whom reported negative parenting in childhood. Half of the sample was identified as having a history of satisfying adult love relationships, while the remainder had experienced ongoing adult relationship problems. Measures of internal working models of attachment were made using the Adult Attachment Interview (AAI). A strong association was found between attachment classifications and the quality of adult love relationships. In addition, women with satisfying love relationships demonstrated significantly higher coherence of mind ratings than those with poor relationship histories. Insecure working models of attachment were associated with problems in adult love relationships. Although secure/autonomous attachment status was linked to optimal adult relationship outcomes, some women with a history of satisfying love relationships had insecure working models of attachment. These results suggest that the ways that adults process early experiences may influence later psychosocial functioning.
Disorganized attachment and inhibitory capacity: predicting externalizing problem behaviors.

PubMed

Bohlin, Gunilla; Eninger, Lilianne; Brocki, Karin Cecilia; Thorell, Lisa B

2012-04-01

The aim of the present study was to investigate whether attachment insecurity, focusing on disorganized attachment, and the executive function (EF) component of inhibition, assessed at age 5, were longitudinally related to general externalizing problem behaviors as well as to specific symptoms of ADHD and Autism spectrum disorder (ASD), and callous-unemotional (CU) traits. General externalizing problem behaviors were also measured at age 5 to allow for a developmental analysis. Outcome variables were rated by parents and teachers. The sample consisted of 65 children with an oversampling of children with high levels of externalizing behaviors. Attachment was evaluated using a story stem attachment doll play procedure. Inhibition was measured using four different tasks. The results showed that both disorganized attachment and poor inhibition were longitudinally related to all outcome variables. Controlling for initial level of externalizing problem behavior, poor inhibition predicted ADHD symptoms and externalizing problem behaviors, independent of disorganized attachment, whereas for ASD symptoms no predictive relations remained. Disorganized attachment independently predicted CU traits.
Genetic and caregiving-based contributions to infant attachment: unique associations with distress reactivity and attachment security.

PubMed

Raby, K Lee; Cicchetti, Dante; Carlson, Elizabeth A; Cutuli, J J; Englund, Michelle M; Egeland, Byron

2012-09-01

In the longitudinal study reported here, we examined genetic and caregiving-based contributions to individual differences in infant attachment classifications. For 154 mother-infant pairs, we rated mothers' responsiveness to their 6-month-old infants during naturalistic interactions and classified infants' attachment organization at 12 and 18 months using the Strange Situation procedure. These infants were later genotyped with respect to the serotonin-transporter-linked polymorphic region (5-HTTLPR). Maternal responsiveness uniquely predicted infants' attachment security. Infants' 5-HTTLPR variation uniquely predicted their subtype of attachment security at 12 months and their subtype of attachment insecurity at 12 and 18 months. The short allele for 5-HTTLPR was associated with attachment classifications characterized by higher emotional distress. These findings suggest that 5-HTTLPR variation contributes to infants' emotional reactivity and that the degree to which caregivers are responsive influences how effectively infants use their caregivers for emotion regulation. Theoretical implications for the study of genetic and caregiving influences are discussed.
Attachment Styles of Dermatological Patients in Europe: A Multi-centre Study in 13 Countries.

PubMed

Szabó, Csanád; Altmayer, Anita; Lien, Lars; Poot, Françoise; Gieler, Uwe; Tomas-Aragones, Lucía; Kupfer, Jörg; Jemec, Gregor B E; Misery, Laurent; Linder, M Dennis; Sampogna, Francesca; van Middendorp, Henriët; Halvorsen, Jon Anders; Balieva, Flora; Szepietowski, Jacek C; Romanov, Dmitry; Marron, Servando E; Altunay, Ilknur K; Finlay, Andrew Y; Salek, Sam S; Dalgard, Florence

2017-07-06

Attachment styles of dermatological outpatients and satisfaction with their dermatologists were investigated within the framework of a multicentre study conducted in 13 European countries, organized by the European Society for Dermatology and Psychiatry. Attachment style was assessed with the Adult Attachment Scale. Patient satisfaction with the dermatologist was assessed with an 11-degree scale. A total of 3,635 adult outpatients and 1,359 controls participated in the study. Dermatological outpatients were less able to depend on others, were less comfortable with closeness and intimacy, and experienced similar rates of anxiety in relationships as did the controls. Participants who had secure attachment styles reported stressful life events during the last 6 months significantly less often than those who had insecure attachment styles. Patients with secure attachment styles tended to be more satisfied with their dermatologist than did insecure patients. These results suggest that secure attachment of dermatological outpatients may be a protective factor in the management of stress.
Gonococcal attachment to eukaryotic cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

James, J.F.; Lammel, C.J.; Draper, D.L.

The attachment of Neisseria gonorrhoeae to eukaryotic cells grown in tissue culture was analyzed by use of light and electron microscopy and by labeling of the bacteria with (/sup 3/H)- and (/sup 14/C)adenine. Isogenic piliated and nonpiliated N. gonorrhoeae from opaque and transparent colonies were studied. The results of light microscopy studies showed that the gonococci attached to cells of human origin, including Flow 2000, HeLa 229, and HEp 2. Studies using radiolabeled gonococci gave comparable results. Piliated N. gonorrhoeae usually attached in larger numbers than nonpiliated organisms, and those from opaque colonies attached more often than isogenic variants frommore » transparent colonies. Day-to-day variation in rate of attachment was observed. Scanning electron microscopy studies showed the gonococcal attachment to be specific for microvilli of the host cells. It is concluded that more N. gonorrhoeae from opaque colonies, as compared with isogenic variants from transparent colonies, attach to eukaryotic cells grown in tissue culture.« less
Interpersonal learning is associated with improved self-esteem in group psychotherapy for women with binge eating disorder.

PubMed

Gallagher, Meagan E; Tasca, Giorgio A; Ritchie, Kerri; Balfour, Louise; Maxwell, Hilary; Bissada, Hany

2014-03-01

Yalom and Leszcz (2005) indicated that interpersonal learning is a key therapeutic factor in group psychotherapy. In this study, we conceptualized interpersonal learning as the convergence over time between an individual's and the group's perception of the individual's cohesion to the group. First, we developed parallel measures of: (a) an individual's self-rated cohesion to the group (Cohesion Questionnaire-Individual Version [CQ-I]), and (b) the group's rating of the individual's cohesion to the group (CQ-G) based on the original Cohesion Questionnaire (CQ; Piper, Marache, Lacroix, Richardsen, & Jones, 1983). Second, we used these parallel scales to assess differences between an individual's self-rating and the mean of the group's ratings of the individual's cohesion to the group. Women with binge eating disorder (N = 102) received Group Psychodynamic Interpersonal Psychotherapy. Participants were assigned to homogeneously composed groups of either high or low attachment anxiety. Outcomes were measured pre- and post-treatment, and the CQ-I and CQ-G were administered every fourth group session. We found significant convergence over time between the CQ-I and mean CQ-G scale scores in both attachment anxiety conditions. Participants with higher attachment anxiety had lower individual self-ratings of cohesion and had greater discrepancies between the CQ-I and CG-G compared with those with lower attachment anxiety. There was a significant relationship between greater convergence in cohesion ratings and improved self-esteem at post-treatment. More accurate self-perceptions through feedback from group members may be a key factor in facilitating increased self-esteem in group therapy. Group therapists may facilitate such interpersonal learning, especially for those higher in attachment anxiety, by noting discrepancies and then encouraging convergence between an individual and the group in their perceptions of cohesion to the group. (c) 2014 APA, all rights reserved.
Pre-attachment Striga hermonthica resistance of New Rice for Africa (NERICA) cultivars based on low strigolactone production.

PubMed

Jamil, Muhammad; Rodenburg, Jonne; Charnikhova, Tatsiana; Bouwmeester, Harro J

2011-12-01

Striga hermonthica (Striga) is an obligate hemiparasitic weed, causing severe yield losses in cereals, including rice, throughout sub-Saharan Africa. Striga germination depends on strigolactones (germination stimulants) exuded by the host roots. The interspecific New Rice for Africa (NERICA) cultivars offer a potentially interesting gene pool for a screen for low germination-inducing rice cultivars. Exudates were collected from all NERICA cultivars and their parents (Oryza sativa and Oryza glaberrima) for the analysis of strigolactones. In vitro and in situ Striga germination, attachment and emergence rates were recorded for each cultivar. NERICA 1 and CG14 produced significantly less strigolactones and showed less Striga infection than the other cultivars. NERICAs 7, 8, 11 and 14 produced the largest amounts of strigolactones and showed the most severe Striga infection. Across all the cultivars and parents, there was a positive relationship between the amount of strigolactones in the exudate and Striga germination, attachment and emergence rates. This study shows that there is genetic variation in Striga pre-attachment resistance in NERICA rice. Cultivars combining this pre-attachment resistance with post-attachment resistance (already identified) can provide a key component for durable integrated management of this noxious weed in cereal production systems in sub-Saharan Africa. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.
Naïve observers' perceptions of family drawings by 7-year-olds with disorganized attachment histories.

PubMed

Madigan, Sheri; Goldberg, Susan; Moran, Greg; Pederson, David R

2004-09-01

Previous research has succeeded in distinguishing among drawings made by children with histories of organized attachment relationships (secure, avoidant, and resistant); however, drawings of children with histories of disorganized attachment have yet to be systematically investigated. The purpose of this study was to determine whether naïve observers would respond differentially to family drawings of 7-year-olds who were classified in infancy as disorganized vs. organized. Seventy-three undergraduate students from one university and 78 from a second viewed 50 family drawings of 7-year-olds (25 by children with organized infant attachment and 25 by children with disorganized infant attachment). Participants were asked to (1) circle the emotion that best described their reaction to the drawings and (2) rate the drawings on 6 bipolar scales. Drawings from children classified as disorganized in infancy evoked positive emotion labels less often and negative emotion labels more often than those children classified as organized. Furthermore, drawings from children classified as disorganized in infancy received higher ratings on scales for disorganization, carelessness, family chaos, bizarreness, uneasiness, and dysfunction. These data indicate that naive observers are relatively successful in distinguishing selected features of drawings by children with histories of disorganized vs. organized attachment.
Attachment representations and socio-emotional difficulties in alternative care: A comparison between residential, foster and family based children in Chile.

PubMed

Garcia Quiroga, Manuela; Hamilton-Giachritsis, Catherine; Ibañez Fanés, Margarita

2017-08-01

Attachment has been assessed in children living in alternative care (AC) settings, such as Residential Homes (RC) and Foster Care (FC). However, no study has been conducted to compare attachment styles in residential, foster and parental care conducted as usual in the same country at the same point in time. There is also a lack of studies conducted in less developed countries. Therefore, the aim of this study was to compare outcomes for children living in three different types of care in Chile. Three groups of children (N=77), living in (RC), (FC) and with biological parents (PC) were compared. Attachment styles, Indiscriminate Friendliness (IF) and socio-emotional/behavioral difficulties were assessed. Higher rates of secure attachment were observed in the RC group (36.1%) when compared to studies in RC in other countries (mean 18%). However, children in both types of AC were significantly more likely to have insecure and/or disorganized attachment styles than PC children. Higher rates of socio-emotional and behavioral problems were observed in RC (55.6%) and FC (50%) compared to PC (10%). Within type of AC, no significant differences were found, for attachment styles or for socio-emotional/behavioral difficulties, the only difference were the levels of IF, with children in RC having higher levels. As a conclusion, impact of placement in AC can vary between different countries, other factors, rather than only type of AC could better explain differences in attachment security for children. Implications for research and practices are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Collisional Dissociation of CO: ab initio Potential Energy Surfaces and Quasiclassical Trajectory Rate Coefficients

NASA Technical Reports Server (NTRS)

Schwenke, David W.; Jaffe, Richard L.; Chaban, Galina M.

2016-01-01

We have generated accurate global potential energy surfaces for CO+Ar and CO+O that correlate with atom-diatom pairs in their ground electronic states based on extensive ab initio electronic structure calculations and used these potentials in quasi-classical trajectory nuclear dynamics calculations to predict the thermal dissociation rate coefficients over 5000- 35000 K. Our results are not compatible with the 20-45 year old experimental results. For CO + Ar we obtain fairly good agreement with the experimental rate coefficients of Appleton et al. (1970) and Mick and Roth (1993), but our computed rate coefficients exhibit a stronger temperature dependence. For CO + O our dissociation rate coefficient is in close agreement with the value from the Park model, which is an empirical adjustment of older experimental results. However, we find the rate coefficient for CO + O is only 1.5 to 3.3 times larger than CO + Ar over the temperature range of the shock tube experiments (8000-15,000 K). The previously accepted value for this rate coefficient ratio is 15, independent of temperature. We also computed the rate coefficient for the CO + O ex- change reaction which forms C + O2. We find this reaction is much faster than previously believed and is the dominant process in the removal of CO at temperatures up to 16,000 K. As a result, the dissociation of CO is accomplished in two steps (react to form C+O2 and then O2 dissociates) that are endothermic by 6.1 and 5.1 eV, instead of one step that requires 11.2 eV to break the CO bond.
Ceramic blade with tip seal

DOEpatents

Glezer, Boris; Bhardwaj, Narender K.; Jones, Russell B.

1997-01-01

The present gas turbine engine (10) includes a disc assembly (64) defining a disc (66) having a plurality of blades (70) attached thereto. The disc (66) has a preestablished rate of thermal expansion and the plurality of blades have a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the disc (66). A shroud assembly (100) is attached to the gas turbine engine (10) and is spaced from the plurality of blades (70) a preestablished distance forming an interface (108) therebetween. Positioned in the interface is a seal (110) having a preestablished rate of thermal expansion being generally equal to the rate of thermal expansion of the plurality of blades (70).
Challenge of assessing symptoms in seriously ill intensive care unit patients: can proxy reporters help?

PubMed

Puntillo, Kathleen A; Neuhaus, John; Arai, Shoshana; Paul, Steven M; Gropper, Michael A; Cohen, Neal H; Miaskowski, Christine

2012-10-01

Determine levels of agreement among intensive care unit patients and their family members, nurses, and physicians (proxies) regarding patients' symptoms and compare levels of mean intensity (i.e., the magnitude of a symptom sensation) and distress (i.e., the degree of emotionality that a symptom engenders) of symptoms among patients and proxy reporters. Prospective study of proxy reporters of symptoms in seriously ill patients. Two intensive care units in a tertiary medical center in the Western United States. Two hundred and forty-five intensive care unit patients, 243 family members, 103 nurses, and 92 physicians. None. On the basis of the magnitude of intraclass correlation coefficients, where coefficients from .35 to .78 are considered to be appropriately robust, correlation coefficients between patients' and family members' ratings met this criterion (≥.35) for intensity in six of ten symptoms. No intensity ratings between patients and nurses had intraclass correlation coefficients >.32. Three symptoms had intensity correlation coefficients of ≥.36 between patients' and physicians' ratings. Correlation coefficients between patients and family members were >.40 for five symptom-distress ratings. No symptoms had distress correlation coefficients of ≥.28 between patients' and nurses' ratings. Two symptoms had symptom-distress correlation coefficients between patients' and physicians' ratings at >.39. Family members, nurses, and physicians reported higher symptom-intensity scores than patients did for 80%, 60%, and 60% of the symptoms, respectively. Family members, nurses, and physicians reported higher symptom-distress scores than patients did for 90%, 70%, and 80% of the symptoms, respectively. Patient-family intraclass correlation coefficients were sufficiently close for us to consider using family members to help assess intensive care unit patients' symptoms. Relatively low intraclass correlation coefficients between intensive care unit clinicians' and patients' symptom ratings indicate that some proxy raters overestimate whereas others underestimate patients' symptoms. Proxy overestimation of patients' symptom scores warrants further study because this may influence decisions about treating patients' symptoms.
Rate Coefficient Measurements of the Reaction CH3 + O2 = CH3O + O

NASA Technical Reports Server (NTRS)

Hwang, S. M.; Ryu, Si-Ok; DeWitt, K. J.; Rabinowitz, M. J.

1999-01-01

Rate coefficients for the reaction CH3 + O2 = CH3O + O were measured behind reflected shock waves in a series of lean CH4-O2-Ar mixtures using hydroxyl and methyl radical diagnostics. The rate coefficients are well represented by an Arrhenius expression given as k = (1.60(sup +0.67, sub -0.47 ) x 10(exp 13) e(-15813 +/- 587 K/T)/cubic cm.mol.s. This expression, which is valid in the temperature range 1575-1822 K, supports the downward trend in the rate coefficients that has been reported in recent determinations. All measurements to date, including the present study, have been to some extent affected by secondary reactions. The complications due to secondary reactions, choice of thermochemical data, and shock-boundary layer interactions that affect the determination of the rate coefficients are examined.

Synthesis and properties of feruloyl corn bran arabinoxylan esters.

PubMed

Li, Y; Yang, C

2016-06-01

To enhance the antioxidant activity and UV absorption coefficient of corn bran arabinoxylan (CAX), ferulic acid (FA) with this physiological activity is used to modify CAX. Corn bran arabinoxylan was extracted from corn bran according to alkaline hydrogen peroxide (AHP) method. FA was covalently linked to CAX by esterification in a two-step feasible synthesis to generate ferulic acid arabinoxylan esters (FA-CAX). The structure and molecular weight of FA-CAX were characterized by NMR and HPSEC, the degrees of substitution (DS) was determined by HPLC, and the ultraviolet (UV) coefficient of FA-CAX was tested by UV spectroscopy. The antioxidant activity of FA-CAX was investigated on the basis of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical assay, and protecting ability of FA-CAX to UV-induced oxidative damage was tested using linolenic acid dispersion as stratum corneum lipid model. The results demonstrated that FA was attached to CAX successfully, and the inherent structure of CAX would not be broken during the process of the synthesis. FA-CAX-1 and FA-CAX-2 contained different amount of FA, with DS at 0.33 and 1.25, respectively, can absorb UV both at UVA and UVB. Moreover, FA-CAX-2 exhibited better antioxidant activity than FA-CAX-1 based on the two test methods. Ferulic acid modified CAX had significant antioxidant ability and UV absorption coefficient. And higher amount of FA leads to higher antioxidant activity and stronger UV absorption and stability. With increasing amount of FA attached to CAX, the antioxidant activities were better and the UV absorption was stronger and more durable. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Spin-dependent Seebeck effects in a graphene superlattice p-n junction with different shapes

NASA Astrophysics Data System (ADS)

Zhou, Benhu; Zhou, Benliang; Yao, Yagang; Zhou, Guanghui; Hu, Ming

2017-10-01

We theoretically calculate the spin-dependent transmission probability and spin Seebeck coefficient for a zigzag-edge graphene nanoribbon p-n junction with periodically attached stubs under a perpendicular magnetic field and a ferromagnetic insulator. By using the nonequilibrium Green’s function method combining with the tight-binding Hamiltonian, it is demonstrated that the spin-dependent transmission probability and spin Seebeck coefficient for two types of superlattices can be modulated by the potential drop, the magnetization strength, the number of periods of the superlattice, the strength of the perpendicular magnetic field, and the Anderson disorder strength. Interestingly, a metal to semiconductor transition occurs as the number of the superlattice for a crossed superlattice p-n junction increases, and its spin Seebeck coefficient is much larger than that for the T-shaped one around the zero Fermi energy. Furthermore, the spin Seebeck coefficient for crossed systems can be much pronounced and their maximum absolute value can reach 528 μV K-1 by choosing optimized parameters. Besides, the spin Seebeck coefficient for crossed p-n junction is strongly enhanced around the zero Fermi energy for a weak magnetic field. Our results provide theoretical references for modulating the thermoelectric properties of a graphene superlattice p-n junction by tuning its geometric structure and physical parameters.
CARBON-RICH MOLECULAR CHAINS IN PROTOPLANETARY AND PLANETARY ATMOSPHERES: QUANTUM MECHANISMS AND ELECTRON ATTACHMENT RATES FOR ANION FORMATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carelli, F.; Grassi, T.; Gianturco, F. A.

The elementary mechanisms through which molecular polyynes could form stable negative ions after interacting with free electrons in planetary atmospheres (e.g., Titan's) are analyzed using quantum scattering calculations and quantum structure methods. The case of radical species and of nonpolar partners are analyzed via specific examples for both the C{sub n}H and HC{sub n}H series, with n values from 4 to 12. We show that attachment processes to polar radicals are dominating the anionic production and that the mediating role of dipolar scattering states is crucial to their formation. The corresponding attachment rates are presented as calculated upper limits tomore » their likely values and are obtained down to the low temperatures of interest. The effects of the computed rates, when used in simple evolutionary models, are also investigated and presented in detail.« less
Removal of microorganisms by deep well injection

NASA Astrophysics Data System (ADS)

Schijven, Jack F.; Medema, Gertjan; Vogelaar, Ad J.; Hassanizadeh, S. Majid

2000-08-01

The removal of bacteriophages MS2 and PRD1, spores of Clostridium bifermentans (R5) and Escherichia coli (WR1) by deep well injection into a sandy aquifer, was studied at a pilot field site in the southeast of the Netherlands. Injection water was seeded with the microorganisms for 5 days. Breakthrough was monitored for 93 days at 4 monitoring wells with their screens at a depth of about 310 m below surface. Within the first 8 m of soil passage, concentrations of MS2 and PRD1 were reduced by 6 log 10, that of R5 spores by 5 log 10 and that of WR1 by 7.5 log 10. Breakthrough of MS2 and R5 could also be followed at greater distances from the injection well. Concentrations of MS2 were reduced only by about 2 log 10 in the following 30 m, and reduction of concentrations of R5 was negligible. Apparently, attachment was greater during the first 8 m of aquifer passage. At the point of injection, the inactivation rate coefficient of free MS2 was found to be 0.081 day -1, that of free PRD1 0.060 day -1, and that of E. coli strain WR1 0.063 day -1. In injection water that had passed 8 m of soil, inactivation of MS2 phages was found to be less than in water from the injection well: 0.039 day -1. Probably, the higher inactivation rate of MS2 in water from the injection well may be ascribed to the activity of aerobic bacteria. Inactivation of the R5 spores was not significant. From geochemical mass balances, it could be deduced that within the first 8 m distance from the injection well, ferric oxyhydroxides precipitated as a consequence of pyrite oxidation, but not at larger distances. Ferric oxyhydroxides provide positively charged patches onto which fast attachment of the negatively charged microorganisms may take place. The non-linear logarithmic reduction of concentrations with distance may therefore be ascribed to preferable attachment of microorganisms to patches of ferric oxyhydroxides that are present within 8 m distance from the injection point, but not thereafter. Declogging of the injection well introduced hydrodynamic shear that remobilized MS2, which was then transported farther downstream.
Semiempirical method of determining flow coefficients for pitot rake mass flow rate measurements

NASA Technical Reports Server (NTRS)

Trefny, C. J.

1985-01-01

Flow coefficients applicable to area-weighted pitot rake mass flow rate measurements are presented for fully developed, turbulent flow in an annulus. A turbulent velocity profile is generated semiempirically for a given annulus hub-to-tip radius ratio and integrated numerically to determine the ideal mass flow rate. The calculated velocities at each probe location are then summed, and the flow rate as indicated by the rake is obtained. The flow coefficient to be used with the particular rake geometry is subsequently obtained by dividing the ideal flow rate by the rake-indicated flow rate. Flow coefficients ranged from 0.903 for one probe placed at a radius dividing two equal areas to 0.984 for a 10-probe area-weighted rake. Flow coefficients were not a strong function of annulus hub-to-tip radius ratio for rakes with three or more probes. The semiempirical method used to generate the turbulent velocity profiles is described in detail.
Thermal Rate Coefficients for the Astrochemical Process C + CH+ → C2+ + H by Ring Polymer Molecular Dynamics.

PubMed

Rampino, Sergio; Suleimanov, Yury V

2016-12-22

Thermal rate coefficients for the astrochemical reaction C + CH + → C 2 + + H were computed in the temperature range 20-300 K by using novel rate theory based on ring polymer molecular dynamics (RPMD) on a recently published bond-order based potential energy surface and compared with previous Langevin capture model (LCM) and quasi-classical trajectory (QCT) calculations. Results show that there is a significant discrepancy between the RPMD rate coefficients and the previous theoretical results that can lead to overestimation of the rate coefficients for the title reaction by several orders of magnitude at very low temperatures. We argue that this can be attributed to a very challenging energy profile along the reaction coordinate for the title reaction, not taken into account in extenso by either the LCM or QCT approximation. In the absence of any rigorous quantum mechanical or experimental results, the computed RPMD rate coefficients represent state-of-the-art estimates to be included in astrochemical databases and kinetic networks.
Calculations on the rate of the ion-molecule reaction between NH3(+) and H2

NASA Technical Reports Server (NTRS)

Herbst, Eric; Defrees, D. J.; Talbi, D.; Pauzat, F.; Koch, W.

1991-01-01

The rate coefficient for the ion-molecule reaction NH3(+) + H2 yields NH4(+) + H has been calculated as a function of temperature with the use of the statistical phase space approach. The potential surface and reaction complex and transition state parameters used in the calculation have been taken from ab initio quantum chemical calculations. The calculated rate coefficient has been found to mimic the unusual temperature dependence measured in the laboratory, in which the rate coefficient decreases with decreasing temperature until 50-100 K and then increases at still lower temperatures. Quantitative agreement between experimental and theoretical rate coefficients is satisfactory given the uncertainties in the ab initio results and in the dynamics calculations. The rate coefficient for the unusual three-body process NH3(+) + H2 + He yields NH4(+) + H + He has also been calculated as a function of temperature and the result found to agree well with a previous laboratory determination.
Assessing Attachment in Psychotherapy: Validation of the Patient Attachment Coding System (PACS).

PubMed

Talia, Alessandro; Miller-Bottome, Madeleine; Daniel, Sarah I F

2017-01-01

The authors present and validate the Patient Attachment Coding System (PACS), a transcript-based instrument that assesses clients' in-session attachment based on any session of psychotherapy, in multiple treatment modalities. One-hundred and sixty clients in different types of psychotherapy (cognitive-behavioural, cognitive-behavioural-enhanced, psychodynamic, relational, supportive) and from three different countries were administered the Adult Attachment Interview (AAI) prior to treatment, and one session for each client was rated with the PACS by independent coders. Results indicate strong inter-rater reliability, and high convergent validity of the PACS scales and classifications with the AAI. These results present the PACS as a practical alternative to the AAI in psychotherapy research and suggest that clinicians using the PACS can assess clients' attachment status on an ongoing basis by monitoring clients' verbal activity. These results also provide information regarding the ways in which differences in attachment status play out in therapy sessions and further the study of attachment in psychotherapy from a pre-treatment client factor to a process variable. Copyright © 2015 John Wiley & Sons, Ltd. The Patient Attachment Coding System is a valid measure of attachment that can classify clients' attachment based on any single psychotherapy transcript, in many therapeutic modalities Client differences in attachment manifest in part independently of the therapist's contributions Client adult attachment patterns are likely to affect psychotherapeutic processes. Copyright © 2015 John Wiley & Sons, Ltd.
Attachment style and suicide behaviors in high risk psychiatric inpatients following hospital discharge: The mediating role of entrapment.

PubMed

Li, Shuang; Galynker, Igor I; Briggs, Jessica; Duffy, Molly; Frechette-Hagan, Anna; Kim, Hae-Joon; Cohen, Lisa J; Yaseen, Zimri S

2017-11-01

Insecure attachment is associated with suicidal behavior. This relationship and its possible mediators have not been examined in high-risk psychiatric inpatients with respect to the critical high-risk period following hospital discharge. Attachment styles and perception of entrapment were assessed in 200 high-risk adult psychiatric inpatients hospitalized following suicidal ideation or suicide attempt. Suicidal behaviors were evaluated with the Columbia Suicide Severity Rating Scale at 1-2 months post-discharge. Associations between different attachment styles and suicidal behaviors were assessed and mediation of attachment effects by entrapment was modeled. Fearful attachment was associated with post-discharge suicidal behavior and there was a trend-level negative association for secure attachment. In addition, entrapment mediated the relationship between fearful attachment and suicidal behavior. The current study highlights the mediating role of perceptions of entrapment in the contribution of fearful attachment to suicidal behavior in high-risk patients, suggesting entrapment as potential therapeutic target to prevent suicidal behavior in these individuals. Further research is warranted to establish the mechanisms by which entrapment experiences emerge in patients with insecure attachment styles. Copyright © 2017 Elsevier B.V. All rights reserved.
Stress analysis of mandibular implant overdenture with locator and bar/clip attachment: Comparative study with differences in the denture base length.

PubMed

Yoo, Jin Suk; Kwon, Kung-Rock; Noh, Kwantae; Lee, Hyeonjong; Paek, Janghyun

2017-06-01

The design of the attachment must provide an optimum stress distribution around the implant. In this study, for implant overdentures with a bar/clip attachment or a locator attachment, the stress transmitted to the implant in accordance with the change in the denture base length and the vertical pressure was measured and analyzed. Test model was created with epoxy resin. The strain gauges made a tight contact with implant surfaces. A universal testing machine was used to exert a vertical pressure on the mandibular implant overdenture and the strain rate of the implants was measured. Means and standard deviations of the maximum micro-deformation rates were determined. 1) Locator attachment: The implants on the working side generally showed higher strain than those on the non-working side. Tensile force was observed on the mesial surface of the implant on the working side, and the compressive force was applied to the buccal surface and on the surfaces of the implant on the non-working side. 2) Bar/clip attachment: The implants on the both non-working and working sides showed high strain; all surfaces except the mesial surface of the implant on the non-working side showed a compressive force. To minimize the strain on implants in mandibular implant overdentures, the attachment of the implant should be carefully selected and the denture base should be extended as much as possible.
Nonlinear Response of Iceberg Melting to Ocean Currents

NASA Astrophysics Data System (ADS)

Cenedese, C.; FitzMaurice, A.; Straneo, F.

2017-12-01

Icebergs calving into Greenlandic Fjords frequently experience strongly sheared flows over their draft, but the impact of this flow past the iceberg on the melt plumes generated along the iceberg sides is not fully captured by existing parameterizations. We present a series of novel laboratory experiments to determine the dependence of side submarine melt rates on a background flow. We show, for the first time, that two distinct regimes of melting exist depending on the melt plume behavior (side-attached or side-detached). These two regimes produce a nonlinear dependence of melt rate on velocity, and different distributions of meltwater in the water column. Iceberg meltwater may either be confined to a thin surface layer, when the melt plumes are side-attached, or mixed down to the iceberg draft, when the melt plumes are side-detached. In a two-layer vertically sheared flow the average flow speed in existing melt parameterizations gives an underestimate of the submarine melt rate, in part due to the nonlinearity of the dependence of melt rate on flow speed, but also because vertical shear in the velocity profile fundamentally changes the flow splitting around the ice block and consequently the velocity felt by the ice surface. Including this nonlinear velocity dependence in melting parameterizations applied to observed icebergs increases iceberg side melt in the attached regime, improving agreement with observations of iceberg submarine melt rates. We show that both attached and detached plume regimes are relevant to icebergs observed in a Greenland fjord.
Effects of harness-attached transmitters on premigration and reproduction of Brant

USGS Publications Warehouse

Ward, David H.; Flint, Paul L.

1995-01-01

Radio transmitters are an important tool in waterfowl ecology studies, but little is known about their effects on free-ranging geese. We attached transmitters to female brant (Branta bernicla nigricans) to investigate migration schedules at a fall staging area, return rates to nesting grounds, and nesting rates of returning females in subsequent breeding seasons. Radio-tagged females (n = 62) carried either 35-g back-mounted transmitters attached with ribbon harnesses, or 26- or 32-g back-mounted transmitters affixed with plastic-coated wire harnesses (Dwyer 1972). Arrival and departure schedules at Izembek Lagoon, Alaska, did not differ (P > 0.05) between radio-tagged females and the entire population in 1987-89. Color-banded females with transmitters returned to the breeding colony in subsequent nesting seasons (1988-92) at a lower (P ≤ 0.003) rate (≤4%) than color-banded females without transmitters (57-83%). The 1 returning color-banded female with a transmitter did not breed, while an average 90% of the returning color-banded females without transmitters nested in subsequent breeding seasons (P = 0.005). Back-mounted, harness-attached transmitters may bias data in studies of waterfowl behavior, productivity, and survival.
Attachment stability and the emergence of unresolved representations during adolescence.

PubMed

Aikins, Julie Wargo; Howes, Carollee; Hamilton, Claire

2009-09-01

This 15-year longitudinal study examined the stability of attachment representations from infancy to adolescence and investigated the emergence of unresolved representations during adolescence in a sample of 47 16-year-olds. Attachment was assessed at 12 months using the Strange Situation Procedure, at 4 years using the modified Strange Situation Procedure, and again at 16 years with the Adult Attachment Projective (AAP). The emergence of unresolved classifications in adolescence (AAP) was associated with higher rates of negative life events, low levels of early mother-child relationship security (an aggregate measure of the 12-month and 4-year measures), negative teacher-child relationship experiences in middle childhood, and low early adolescent friendship quality. The results support the growing body of evidence suggesting that changes in attachment are lawful, while adding to the growing understanding of the emergence of unresolved attachment representations.
A solution procedure for behavior of thick plates on a nonlinear foundation and postbuckling behavior of long plates

NASA Technical Reports Server (NTRS)

Stein, M.; Stein, P. A.

1978-01-01

Approximate solutions for three nonlinear orthotropic plate problems are presented: (1) a thick plate attached to a pad having nonlinear material properties which, in turn, is attached to a substructure which is then deformed; (2) a long plate loaded in inplane longitudinal compression beyond its buckling load; and (3) a long plate loaded in inplane shear beyond its buckling load. For all three problems, the two dimensional plate equations are reduced to one dimensional equations in the y-direction by using a one dimensional trigonometric approximation in the x-direction. Each problem uses different trigonometric terms. Solutions are obtained using an existing algorithm for simultaneous, first order, nonlinear, ordinary differential equations subject to two point boundary conditions. Ordinary differential equations are derived to determine the variable coefficients of the trigonometric terms.
Deployment and Performance Characteristics of 5-Foot Diameter (1.5m) Attached Inflatable Decelerators from Mach Numbers 2.2-4.4

NASA Technical Reports Server (NTRS)

Bohon, Herman L.; Miserentino, Robert

1970-01-01

Deployment characteristics and steady-state performance data were obtained over the Mach number range from 2.2 to 4.4 and at angles of attack from 0 degrees to l0 degrees. All attached inflatable decelerator (AID) models deployed successfully and exhibited flutter-free performance after deployment. Shock loads commonly associated with inflation of parachutes during deployment were not experienced. Force and moment data and ram-air pressure data were obtained throughout the Mach number range and at angles of attack from 0 degrees to l0 degrees. The high drag coefficient of 1.14 was in good agreement with the value predicted by the theory used in the design and indicated other AID shapes may be designed on a rational basis with a high degree of confidence.
Free vibration investigation of nano mass sensor using differential transformation method

NASA Astrophysics Data System (ADS)

Zarepour, Misagh; Hosseini, S. Amirhosein; Ghadiri, Majid

2017-03-01

In the present study, transverse vibration of nano-cantilever beam with attached mass and two rotational and transverse springs at its end is studied. Resonance frequency of vibrating system is influenced by changing mass particle and stiffness coefficients. Euler-Bernoulli beam theory, nonlocal constitutive equations of Eringen, and Hamilton's principle are used to develop equations of motion. Differential transformation method (DTM) is applied to solve the governing equations of the nanobeam with attached mass particle. Accurate results with minimum mathematical calculation are the advantages of DTM. A detailed parametric study is conducted to investigate the influences of nonlocal parameter. The results can be used in designing of nanoelectromechanical systems. To verify the results, some comparisons are presented between differential transform method results and open literature to show the accuracy of this new approach.
Development of a technique for the in vivo assessment of flatulence in dogs.

PubMed

Collins, S B; Perez-Camargo, G; Gettinby, G; Butterwick, R F; Batt, R M; Giffard, C J

2001-07-01

To develop a noninvasive method for the in vivo assessment of flatulence in dogs. 8 adult dogs. Rectal gases were collected via a perforated tube held close to each dog's anus and attached to a monitoring pump fitted with a sensor that recorded hydrogen sulfide concentrations every 20 seconds. Patterns of flatulence were monitored for 14 hours after feeding on 4 days, and within- and between-dog variation was assessed over 4 hours on 4 consecutive days. Rate of hydrogen sulfide production (flatulence index) and frequency and number of emissions were evaluated as potential indicators of flatus characteristics. An odor judge assigned an odor rating to each flatulence episode, and the relationship between that rating and hydrogen sulfide concentration was determined. Flatulence patterns varied within and between dogs. Variation was most pronounced for flatulence index; mean coefficients of variance within dogs over time and between dogs on each day were 75 and 103%, respectively. Flatus with hydrogen sulfide concentrations > 1 parts per million could be detected by the odor judge, and severity of malodor was highly correlated with hydrogen sulfide concentration. Odor ratings were accurately predicted by use of the equation 1.51 X hydrogen sulfide concentration(0.28). The technique described in this report appears to provide sensitive, reliable, and relevant data and will enable further studies of the factors that influence flatulence in dogs. Use of this technique also has the potential to aid in investigations of colonic physiology and pathology.
Intergenerational Transmission of Internalizing Behavior: The Role of Maternal Psychopathology, Child Responsiveness and Maternal Attachment Style Insecurity.

PubMed

Reck, Corinna; Nonnenmacher, Nora; Zietlow, Anna-Lena

Maternal depression and anxiety disorders are risk factors for the development of internalizing disorders in offspring. Maternal attachment has been discussed as one factor accounting for transmission. The aim of this study was to investigate child internalizing behavior at preschool age on a symptomatic and behavioral level and possible links to maternal mental health over time and maternal attachment style insecurity in a sample of postpartum depressed and anxious mothers. Child internalizing behavior at preschool age was rated by the Child Behavior Checklist (CBCL), the Caregiver-Teacher Report Form (C-TRF), and during a mother-child free-play situation. We focused on child responsiveness as it has been linked to child internalizing behavior. Maternal attachment style insecurity was tested to mediate the link between maternal mental health (assessed postpartum and at preschool age with the Structured Clinical Interview for DSM-IV Axis-I Disorders, SCID-I) and child internalizing behavior/child responsiveness. Of the overall sample (n = 58), 28 women were diagnosed with postpartum depression and/or anxiety disorders according to DSM-IV, and 30 were healthy controls. Data were collected 3-9 months after delivery and at preschool age (mean = 4.6 years). At preschool age, children of postpartum depressed and anxious mothers were rated significantly higher on child internalizing behavior by mothers, fathers, and additional caregivers compared to the control group. Child internalizing behavior rated by mothers was influenced by current psychiatric symptoms; maternal attachment style insecurity did not mediate this link. During interaction, children in the clinical group displayed significantly less child responsiveness compared to the control group. Maternal attachment style insecurity mediated the relationship between maternal mental health over time and child responsiveness. The results emphasize the need for interventions focusing on mother-child interaction and maternal attachment. © 2016 S. Karger AG, Basel.
Dynamics of Flagellum- and Pilus-Mediated Association of Pseudomonas aeruginosa with Contact Lens Surfaces▿

PubMed Central

Tran, Victoria B.; Fleiszig, Suzanne M. J.; Evans, David J.; Radke, Clayton J.

2011-01-01

Flagella and pili are appendages that modulate attachment of Pseudomonas aeruginosa to solid surfaces. However, previous studies have mostly reported absolute attachment. Neither the dynamic roles of these appendages in surface association nor those of attachment phenotypes have been quantified. We used video microscopy to address this issue. Unworn, sterile, soft contact lenses were placed in a laminar-flow optical chamber. Initial lens association kinetics for P. aeruginosa strain PAK were assessed in addition to lens-surface association phenotypes. Comparisons were made to strains with mutations in flagellin (fliC) or pilin (pilA) or those in flagellum (motAB) or pilus (pilU) function. PAK and its mutants associated with the contact lens surface at a constant rate according to first-order kinetics. Nonswimming mutants associated ∼30 to 40 times slower than the wild type. PAK and its pilA mutant associated at similar rates, but each ∼4 times faster than the pilU mutant. Lens attachment by wild-type PAK induced multiple phenotypes (static, lateral, and rotational surface movement), each showing only minor detachment. Flagellin (fliC) and flagellar-motility (motAB) mutants did not exhibit surface rotation. Conversely, strains with mutations in pilin (pilA) and pilus retraction (pilU) lacked lateral-surface movement but displayed enhanced surface rotation. Slower surface association of swimming-incapable P. aeruginosa mutants was ascribed to lower convective-diffusion-arrival rates, not to an inability to adhere. Flagellum function (swimming) enhanced lens association, attachment, and rotation; hyperpiliation hindered lens association. P. aeruginosa bound through three different adhesion sites: flagellum, pili, and body. Reduction of bacterial attachment to contact lenses thus requires blockage of multiple adhesion phenotypes. PMID:21498762
Attachment style dimensions can affect prolonged grief risk in caregivers of terminally ill patients with cancer.

PubMed

Lai, Carlo; Luciani, Massimiliano; Galli, Federico; Morelli, Emanuela; Cappelluti, Roberta; Penco, Italo; Aceto, Paola; Lombardo, Luigi

2015-12-01

The aim of the present study was to evaluate the predictive role of attachment dimensions on the risk of prolonged grief. Sixty caregivers of 51 terminally ill patients with cancer who had been admitted in a hospice were selected. Caregivers were interviewed using Attachment Scale Questionnaire, Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, and Prolonged Grief Disorder 12 (PG-12). The consort caregivers showed higher PG-12 level compared to the sibling caregivers. Anxiety, depression, need for approval, and preoccupation with relationships levels were significantly correlated with PG-12 scores. Female gender, high levels of depression, and preoccupation with relationships significantly predicted higher levels of prolonged grief risk. © The Author(s) 2014.

Cumulative Childhood Trauma and Therapeutic Alliance: The Moderator Role of Attachment in Adult Patients Consulting in Sex Therapy.

PubMed

Lafrenaye-Dugas, Anne-Julie; Godbout, Natacha; Hébert, Martine

2018-03-05

While it is documented that clients consulting in sex therapy tend to report high rates of childhood interpersonal traumas (e.g., physical, psychological and sexual abuse), which are associated to insecure attachment and poorer therapeutic alliance, the interrelations of these variables have not yet been evaluated in this specific population. This study examined the associations between attachment, cumulative trauma and therapeutic alliance in 278 sex therapy patients who filled out self-report questionnaires. Results revealed that avoidant attachment acted as a moderator between cumulative trauma and the agreement on tasks dimension of therapeutic alliance. Results suggests the relevance for sex therapists to investigate past traumas and current attachment representations to guide interventions and optimize treatment benefits.
Inelastic rate coefficients for collisions of C6H- with H2 and He

NASA Astrophysics Data System (ADS)

Walker, Kyle M.; Lique, François; Dumouchel, Fabien; Dawes, Richard

2017-04-01

The recent detection of anions in the interstellar medium has shown that they exist in a variety of astrophysical environments - circumstellar envelopes, cold dense molecular clouds and star-forming regions. Both radiative and collisional processes contribute to molecular excitation and de-excitation in these regions so that the 'local thermodynamic equilibrium' approximation, where collisions cause the gas to behave thermally, is not generally valid. Therefore, along with radiative coefficients, collisional excitation rate coefficients are needed to accurately model the anionic emission from these environments. We focus on the calculation of state-to-state rate coefficients of the C6H- molecule in its ground vibrational state in collisions with para-H2, ortho-H2 and He using new potential energy surfaces. Dynamical calculations for the pure rotational excitation of C6H- were performed for the first 11 rotational levels (up to j1 = 10) using the close-coupling method, while the coupled-states approximation was used to extend the H2 rate coefficients to j1 = 30, where j1 is the angular momentum quantum number of C6H-. State-to-state rate coefficients were obtained for temperatures ranging from 2 to 100 K. The rate coefficients for H2 collisions for Δj1 = -1 transitions are of the order of 10-10 cm3 s-1, a factor of 2 to 3 greater than those of He. Propensity rules are discussed. The collisional excitation rate coefficients produced here impact astrophysical modelling since they are required for obtaining accurate C6H- level populations and line emission for regions that contain anions.
Development and validity of methods for the estimation of temporal gait parameters from heel-attached inertial sensors in younger and older adults.

PubMed

Misu, Shogo; Asai, Tsuyoshi; Ono, Rei; Sawa, Ryuichi; Tsutsumimoto, Kota; Ando, Hiroshi; Doi, Takehiko

2017-09-01

The heel is likely a suitable location to which inertial sensors are attached for the detection of gait events. However, there are few studies to detect gait events and determine temporal gait parameters using sensors attached to the heels. We developed two methods to determine temporal gait parameters: detecting heel-contact using acceleration and detecting toe-off using angular velocity data (acceleration-angular velocity method; A-V method), and detecting both heel-contact and toe-off using angular velocity data (angular velocity-angular velocity method; V-V method). The aim of this study was to examine the concurrent validity of the A-V and V-V methods against the standard method, and to compare their accuracy. Temporal gait parameters were measured in 10 younger and 10 older adults. The intra-class correlation coefficients were excellent in both methods compared with the standard method (0.80 to 1.00). The root mean square errors of stance and swing time in the A-V method were smaller than the V-V method in older adults, although there were no significant discrepancies in the other comparisons. Our study suggests that inertial sensors attached to the heels, using the A-V method in particular, provide a valid measurement of temporal gait parameters. Copyright © 2017 Elsevier B.V. All rights reserved.
Design and Verification of Space Station EVA-Operated Truss Attachment System

NASA Technical Reports Server (NTRS)

Katell, Gabriel

2001-01-01

This paper describes the design and verification of a system used to attach two segments of the International Space Station (ISS). This system was first used in space to mate the P6 and Z1 trusses together in December 2000, through a combination of robotic and extravehicular tasks. Features that provided capture, coarse alignment, and fine alignment during the berthing process are described. Attachment of this high value hardware was critical to the ISS's sequential assembly, necessitating the inclusion of backup design and operational features. Astronauts checked for the proper performance of the alignment and bolting features during on-orbit operations. During berthing, the system accommodates truss-to-truss relative displacements that are caused by manufacturing tolerances and on-orbit thermal gradients. After bolt installation, the truss interface becomes statically determinate with respect to in-plane shear loads and isolates attach bolts from bending moments. The approach used to estimate relative displacements and the means of accommodating them is explained. Confidence in system performance was achieved through a cost-effective collection of tests and analyses, including thermal, structural, vibration, misalignment, contact dynamics, underwater simulation, and full-scale functional testing. Design considerations that have potential application to other mechanisms include accommodating variations of friction coefficients in the on-orbit joints, wrench torque tolerances, joint preload, moving element clearances at temperature extremes, and bolt-nut torque reaction.
Surface-attached and suspended bacterial community structure as affected by C/N ratios: relationship between bacteria and fish production.

PubMed

Yu, Ermeng; Xie, Jun; Wang, Jinlin; Ako, Harry; Wang, Guangjun; Chen, Zhanghe; Liu, Yongfeng

2016-07-01

Bacteria play crucial roles in the combined system of substrate addition and C/N control, which has been demonstrated to improve aquaculture production. However, the complexity of surface-attached bacteria on substrates and suspended bacteria in the water column hamper further application of this system. This study firstly applied this combined system into the culture of grass carp, and then explored the relationship between microbial complexes from surface-attached and suspended bacteria in this system and the production of grass carp. In addition, this study investigated bacterial community structures as affected by four C/N ratios using Illumina sequencing technology. The results demonstrated that the weight gain rate and specific growth rate of grass carp in the CN20 group (C/N ratio 20:1) were the highest (P < 0.05), and dietary supplementation of the microbial complex had positive effects on the growth of grass carp (P < 0.05). Sequencing data revealed that, (1) the proportions of Verrucomicrobiae and Rhodobacter (surface-attached), sediminibacterium (suspended), and emticicia (surface-attached and suspended) were much higher in the CN20 group compared with those in the other groups (P < 0.05); (2) Rhodobacter, Flavobacterium, Acinetobacter, Pseudomonas, Planctomyces, and Cloacibacterium might be important for the microbial colonization on substrates; (3) as the C/N ratio increased, proportions of Hydrogenophaga (surface-attached and suspended), Zoogloea, and Flectobacillus (suspended) increased, but proportions of Bacillus, Clavibacter, and Cellvibro (surface-attached and suspended) decreased. In summary, a combined system of substrate addition and C/N control increased the production of grass carp, and Verrucomicrobiae and Rhodobacter in the surface-attached bacterial community were potential probiotic bacteria that contributed to the enhanced growth of grass carp.
Viscous slip coefficients for binary gas mixtures measured from mass flow rates through a single microtube

NASA Astrophysics Data System (ADS)

Yamaguchi, H.; Takamori, K.; Perrier, P.; Graur, I.; Matsuda, Y.; Niimi, T.

2016-09-01

The viscous slip coefficient for helium-argon binary gas mixture is extracted from the experimental values of the mass flow rate through a microtube. The mass flow rate is measured by the constant-volume method. The viscous slip coefficient was obtained by identifying the measured mass flow rate through a microtube with the corresponding analytical expression, which is a function of the Knudsen number. The measurements were carried out in the slip flow regime where the first-order slip boundary condition can be applied. The measured viscous slip coefficients of binary gas mixtures exhibit a concave function of the molar ratio of the mixture, showing a similar profile with numerical results. However, from the detailed comparison between the measured and numerical values with the complete and incomplete accommodation at a surface, it is inappropriate to estimate the viscous slip coefficient for the mixture numerically by employing separately measured tangential momentum accommodation coefficient for each component. The time variation of the molar ratio in the downstream chamber was measured by sampling the gas from the chamber using the quadrupole mass spectrometer. In our measurements, it is indicated that the volume flow rate of argon is larger than that of helium because of the difference in the tangential momentum accommodation coefficient.
Attachment security as a mechanism linking foster care placement to improved mental health outcomes in previously institutionalized children.

PubMed

McLaughlin, Katie A; Zeanah, Charles H; Fox, Nathan A; Nelson, Charles A

2012-01-01

Children reared in institutions experience elevated rates of psychiatric disorders. Inability to form a secure attachment relationship to a primary caregiver is posited to be a central mechanism in this association. We determined whether the ameliorative effect of a foster care (FC) intervention on internalizing disorders in previously institutionalized children was explained by the development of secure attachment among children placed in FC. Second we evaluated the role of lack of attachment in an institutionalized sample on the etiology of internalizing disorders within the context of a randomized trial. A sample of 136 children (aged 6-30 months) residing in institutions was recruited in Bucharest, Romania. Children were randomized to FC (n = 68) or to care as usual (CAU; n = 68). Foster parents were recruited, trained, and overseen by the investigative team. Attachment security at 42 months was assessed using the Strange Situation Procedure, and internalizing disorders at 54 months were assessed using the Preschool Age Psychiatric Assessment. Girls in FC had fewer internalizing disorders than girls in CAU (OR = 0.17, p = .006). The intervention had no effect on internalizing disorders in boys (OR = 0.47, p = .150). At 42 months, girls in FC were more likely to have secure attachment than girls in CAU (OR = 12.5, p < .001), but no difference was observed in boys (OR = 2.0, p = .205). Greater attachment security predicted lower rates of internalizing disorders in both sexes. Development of attachment security fully mediated intervention effects on internalizing disorders in girls. Placement into FC facilitated the development of secure attachment and prevented the onset of internalizing disorders in institutionalized girls. The differential effects of FC on attachment security in boys and girls explained gender differences in the intervention effects on psychopathology. Findings provide evidence for the critical role of disrupted attachment in the etiology of internalizing disorders in children exposed to institutionalization. © 2011 The Authors. Journal of Child Psychology and Psychiatry © 2011 Association for Child and Adolescent Mental Health.
Frailty effects in networks: comparison and identification of individual heterogeneity versus preferential attachment in evolving networks

PubMed Central

de Blasio, Birgitte Freiesleben; Seierstad, Taral Guldahl; Aalen, Odd O

2011-01-01

Preferential attachment is a proportionate growth process in networks, where nodes receive new links in proportion to their current degree. Preferential attachment is a popular generative mechanism to explain the widespread observation of power-law-distributed networks. An alternative explanation for the phenomenon is a randomly grown network with large individual variation in growth rates among the nodes (frailty). We derive analytically the distribution of individual rates, which will reproduce the connectivity distribution that is obtained from a general preferential attachment process (Yule process), and the structural differences between the two types of graphs are examined by simulations. We present a statistical test to distinguish the two generative mechanisms from each other and we apply the test to both simulated data and two real data sets of scientific citation and sexual partner networks. The findings from the latter analyses argue for frailty effects as an important mechanism underlying the dynamics of complex networks. PMID:21572513
Fragment generation, survival, and attachment of Dictyota spp. at Conch Reef in the Florida Keys, USA

NASA Astrophysics Data System (ADS)

Herren, L. W.; Walters, L. J.; Beach, K. S.

2006-05-01

During the past decade, the relative abundance of the brown macroalgae Dictyota spp. has been high in the Florida Keys. Recent studies have shown that members of this genus successfully reproduce via vegetative fragmentation. To investigate the importance of fragmentation on the reef community, this study examined: (1) the degree of epiphytism on benthic organisms, (2) the rate of fragment production through fish foraging activities, (3) the likelihood of fragment entanglement, and (4) the fragment attachment and success rate. It was found that reef fish contributed substantially to the fragment pool; furthermore, most fish-produced fragments produced rhizoids and attached to sand grains within 24 h in the field. Fragments of Dictyota spp. most commonly became entangled around and then attached themselves to the green alga Halimeda tuna, and other Dictyota spp. These results suggest that vegetative fragmentation of Dictyota spp. plays an important role in the changing community structure on the Florida Keys reef tract.
Ceramic blade attachment system

DOEpatents

Shaffer, J.E.

1995-01-10

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figures.
Ceramic blade attachment system

DOEpatents

Shaffer, James E.

1995-01-01

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.
Transitions in Friendship Attachment in Adolescence is Associated with Developmental Trajectories of Depression through Adulthood

PubMed Central

Heinze, Justin; Miller, Alison L.; Zimmerman, Marc A.

2015-01-01

Purpose Forming secure friendship attachments during adolescence are important for mental health; few, however, have specifically examined the ways in which the transitions in attachment during adolescence may influence future mental health outcomes among African-Americans. Method The current study examines how transitions in attachment in adolescence predicted changes in depression symptoms from late adolescents through adulthood in an African-American sample of adolescents. We used growth curve modeling to examine the association between transitions in friendship attachment and changes in depression symptoms in adulthood. Results At age 16, 346 (64.0%) reported secure attachment with 195 (36.0%) reporting either avoidant or resistant attachment. At age 17, 340 (62.9%) reported secure attachment and 201 (37.2%) reported avoidant or resistant attachment. The largest percentage of participants (46.2%) reported stable-secure attachment across the two time points. Results of the growth model indicated that adolescents who reported a stable-secure attachment style had lower levels of depression symptoms during adulthood than those individuals who transitioned from secure-to-insecure, from insecure-to-secure, or were in the stable-insecure group. Interestingly enough, individuals in both of the attachment transition groups had a faster declining rate of depression symptoms over time compared to the two stability groups. Conclusion Data support existing research showing an association between transitions in attachment during adolescence and depression through adulthood. Further these study findings suggest there may be protective features associated with transitioning between attachment styles during adolescence on later depression, compared to African-American’s who remain stable in their attachment style. PMID:26903426
Partners' Empathy Increases Pain Ratings: Effects of Perceived Empathy and Attachment Style on Pain Report and Display

PubMed Central

Hurter, Sarah; Paloyelis, Yannis; de C. Williams, Amanda C.; Fotopoulou, Aikaterini

2014-01-01

Pain can be influenced by its social context. We aimed to examine under controlled experimental conditions how empathy from a partner and personal attachment style affect pain report, tolerance, and facial expressions of pain. Fifty-four participants, divided into secure, anxious, and avoidant attachment style groups, underwent a cold pressor task with their partners present. We manipulated how much empathy the participants perceived that their partners had for them. We observed a significant main effect of perceived empathy on pain report, with greater pain reported in the high perceived empathy condition. No such effects were found for pain tolerance or facial display. We also found a significant interaction of empathy with attachment style group, with the avoidant group reporting and displaying less pain than the secure and the anxious groups in the high perceived empathy condition. No such findings were observed in the low empathy condition. These results suggest that empathy from one's partner may influence pain report beyond behavioral reactions. In addition, the amount of pain report and expression that people show in high empathy conditions depends on their attachment style. Perspective Believing that one's partner feels high empathy for one's pain may lead individuals to rate the intensity of pain as higher. Individual differences in attachment style moderate this empathy effect. PMID:24953886
Maternal antenatal depression and infant disorganized attachment at 12 months.

PubMed

Hayes, Lisa J; Goodman, Sherryl H; Carlson, Elizabeth

2013-01-01

Although high rates of attachment disorganization have been observed in infants of depressed mothers, little is known about the role of antenatal depression as a precursor to infant attachment disorganization. The primary aim of this study was to examine associations between maternal antenatal depression and infant disorganization at 12 months in a sample of women (N = 79) at risk for perinatal depression. A secondary aim was to test the roles of maternal postpartum depression and maternal parenting quality as potential moderators of this predicted association. Among women with histories of major depressive episodes, maternal depressive symptoms were assessed at multiple times during pregnancy and the first year postpartum, maternal parenting quality was measured at three months postpartum, and attachment disorganization was assessed at 12 months postpartum. Results revealed that infants classified as disorganized had mothers with higher levels of depressive symptoms during pregnancy compared to infants classified as organized. Maternal parenting quality moderated this association, as exposure to higher levels of maternal depressive symptoms during pregnancy was only associated with higher rates of infant disorganized attachment when maternal parenting at three months was less optimal. These findings suggest that enhancing maternal parenting behaviors during this early period in development has the potential to alter pathways to disorganized attachment among infants exposed to antenatal maternal depressive symptoms, which could have enduring consequences for child wellbeing.
Maternal Antenatal Depression and Infant Disorganized Attachment at 12 months

PubMed Central

Hayes, Lisa J.; Goodman, Sherryl H.; Carlson, Elizabeth

2012-01-01

Although high rates of attachment disorganization have been observed in infants of depressed mothers, little is known about the role of antenatal depression as a precursor to infant attachment disorganization. The primary aim of this study was to examine associations between maternal antenatal depression and infant disorganization at 12 months in a sample of women (N = 79) at risk for perinatal depression. A secondary aim was to test the roles of maternal postpartum depression and maternal parenting quality as potential moderators of this predicted association. Among women with histories of major depressive episodes, maternal depressive symptoms were assessed at multiple times during pregnancy and the first year postpartum, maternal parenting quality was measured at 3 months postpartum, and attachment disorganization was assessed at 12 months postpartum. Results revealed that infants classified as disorganized had mothers with higher levels of depressive symptoms during pregnancy compared to infants classified as organized. Maternal parenting quality moderated this association, as exposure to higher levels of maternal depressive symptoms during pregnancy was only associated with higher rates of infant disorganized attachment when maternal parenting at 3 months was less optimal. These findings suggest that enhancing maternal parenting behaviors during this early period in development has the potential to alter pathways to disorganized attachment among infants exposed to antenatal maternal depressive symptoms, which could have enduring consequences for child wellbeing. PMID:23216358
Attachment representations in mothers with abnormal illness behaviour by proxy.

PubMed

Adshead, Gwen; Bluglass, Kerry

2005-10-01

Abnormal illness behaviour by proxy (also known as factitious illness by proxy or Munchhausen syndrome by proxy) is a type of child maltreatment, the origins of which are poorly understood. To describe attachment representations in a cohort of mothers demonstrating abnormal illness behaviour by proxy. Sixty-seven mothers who had shown this behaviour took part in a semistructured interview assessing their attachment representations. Only 12 mothers (18%) were rated secure in terms of their own childhood attachments. There was evidence of unresolved trauma or loss reactions in 40 mothers (60%). Eighteen mothers (27%) gave unusually disorganised and incoherent accounts of attachment relationships in their own childhoods. The frequency of these attachment categories is higher than in normal non-clinical samples. Insecure attachment is a risk factor for this type of child maltreatment. Therapeutic interventions could be offered in relation to unresolved traumatic stress or bereavement responses. Further study of similar groups, such as mothers with sick children or mothers with histories of traumatic experience, would be a useful next step.
Relations among perceived parental rearing behaviors, attachment style, and worry in anxious children.

PubMed

Brown, Amy M; Whiteside, Stephen P

2008-01-01

The present study extended the findings of Muris et al. [Muris, P., Meesters, C., Merckelbach, H., & Hulsenbeck, P. (2000). Worry in children is related to perceived parental rearing and attachment. Behavior Research and Therapy, 38, 487-497] regarding the relations between perceived parental rearing behaviors, self-reported attachment style, and worry in a community sample to a clinical sample of anxious children. Sixty-four children and adolescents, aged 7-18 years, with a primary anxiety disorder completed (a) the EMBU-C, a questionnaire measuring perceptions of parental rearing behaviors, (b) a single-item measure of attachment style, and (c) an index of worry severity. Findings revealed that child rated parental rearing behaviors, particularly parental rejection, were positively related to child worry. Self-reported attachment style was also related to worry, such that children who classified themselves as ambivalently attached reported higher levels of worry than did children who classified themselves as securely attached. Parenting style and attachment were found to make independent contributions to worry. The results are compared to those from Muris et al.'s community study, and implications for future research are discussed.
Intimate Partner Violence and Children’s Attachment Representations during Middle Childhood

PubMed Central

Gustafsson, Hanna C.; Brown, Geoffrey L.; Mills-Koonce, W. Roger; Cox, Martha. J.

2016-01-01

Despite long-standing hypotheses that intimate partner violence (IPV) may undermine children’s ability to form secure attachment representations, few studies have empirically investigated this association. Particularly lacking is research that examines IPV and attachment during middle childhood, a time when the way that children understand, represent, and process the behavior of others becomes particularly important. Using data from a sample of African American children living in rural, low-income communities (n = 98), the current study sought to address this gap by examining the association between physical IPV occurring early in children’s lives and their attachment security during the first grade. Results indicate that, even after controlling for child- and family-level covariates, physical IPV was associated with a greater likelihood of being rated insecurely attached. This effect was above and beyond the influence of maternal parenting behaviors, demonstrating a unique effect of physical IPV on children’s attachment representations during middle childhood. PMID:28781383
Intimate Partner Violence and Children's Attachment Representations during Middle Childhood.

PubMed

Gustafsson, Hanna C; Brown, Geoffrey L; Mills-Koonce, W Roger; Cox, Martha J

2017-06-01

Despite long-standing hypotheses that intimate partner violence (IPV) may undermine children's ability to form secure attachment representations, few studies have empirically investigated this association. Particularly lacking is research that examines IPV and attachment during middle childhood, a time when the way that children understand, represent, and process the behavior of others becomes particularly important. Using data from a sample of African American children living in rural, low-income communities ( n = 98), the current study sought to address this gap by examining the association between physical IPV occurring early in children's lives and their attachment security during the first grade. Results indicate that, even after controlling for child- and family-level covariates, physical IPV was associated with a greater likelihood of being rated insecurely attached. This effect was above and beyond the influence of maternal parenting behaviors, demonstrating a unique effect of physical IPV on children's attachment representations during middle childhood.
Adult attachment in the clinical management of borderline personality disorder.

PubMed

Fossati, Andrea

2012-05-01

Borderline personality disorder (BPD) is a common psychiatric disorder associated with severe functional impairment, high rates of suicide and comorbid psychiatric illness, intensive use of treatment, and high costs to society. The etiology and pathogenesis of BPD are still uncertain, although an interaction between biological and psychosocial factors has been proposed to explain how the condition develops. Attachment disturbances represent one of the developmental risk factors that have been most consistently found to be associated with BPD, with a number of studies reporting a significant strong association between insecure attachment and BPD, notwithstanding the variety of measures and attachment types employed in these studies. In this article, the author first reviews clinical descriptions and research findings concerning the association between attachment disturbances and BPD and then discusses how attachment theory may help clinicians who work with patients with BPD better understand the psychopathology of the illness and plan treatment.

Absolute rate coefficients for photorecombination of beryllium-like and boron-like silicon ions

NASA Astrophysics Data System (ADS)

Bernhardt, D.; Becker, A.; Brandau, C.; Grieser, M.; Hahn, M.; Krantz, C.; Lestinsky, M.; Novotný, O.; Repnow, R.; Savin, D. W.; Spruck, K.; Wolf, A.; Müller, A.; Schippers, S.

2016-04-01

We report measured rate coefficients for electron-ion recombination of Si10+ forming Si9+ and of Si9+ forming Si8+, respectively. The measurements were performed using the electron-ion merged-beams technique at a heavy-ion storage ring. Electron-ion collision energies ranged from 0 to 50 eV for Si9+ and from 0 to 2000 eV for Si10+, thus, extending previous measurements for Si10+ (Orban et al 2010 Astrophys. J. 721 1603) to much higher energies. Experimentally derived rate coefficients for the recombination of Si9+ and Si10+ ions in a plasma are presented along with simple parameterizations. These rate coefficients are useful for the modeling of the charge balance of silicon in photoionized plasmas (Si9+ and Si10+) and in collisionally ionized plasmas (Si10+ only). In the corresponding temperature ranges, the experimentally derived rate coefficients agree with the latest corresponding theoretical results within the experimental uncertainties.
Effective dose rate coefficients for exposure to contaminated soil

DOE PAGES

Veinot, Kenneth G.; Eckerman, Keith F.; Bellamy, Michael B.; ...

2017-05-10

The Oak Ridge National Laboratory Center for Radiation Protection Knowledge has undertaken calculations related to various environmental exposure scenarios. A previous paper reported the results for submersion in radioactive air and immersion in water using age-specific mathematical phantoms. This paper presents age-specific effective dose rate coefficients derived using stylized mathematical phantoms for exposure to contaminated soils. Dose rate coefficients for photon, electron, and positrons of discrete energies were calculated and folded with emissions of 1252 radionuclides addressed in ICRP Publication 107 to determine equivalent and effective dose rate coefficients. The MCNP6 radiation transport code was used for organ dose ratemore » calculations for photons and the contribution of electrons to skin dose rate was derived using point-kernels. Bremsstrahlung and annihilation photons of positron emission were evaluated as discrete photons. As a result, the coefficients calculated in this work compare favorably to those reported in the US Federal Guidance Report 12 as well as by other authors who employed voxel phantoms for similar exposure scenarios.« less
Effective dose rate coefficients for exposure to contaminated soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veinot, Kenneth G.; Eckerman, Keith F.; Bellamy, Michael B.

The Oak Ridge National Laboratory Center for Radiation Protection Knowledge has undertaken calculations related to various environmental exposure scenarios. A previous paper reported the results for submersion in radioactive air and immersion in water using age-specific mathematical phantoms. This paper presents age-specific effective dose rate coefficients derived using stylized mathematical phantoms for exposure to contaminated soils. Dose rate coefficients for photon, electron, and positrons of discrete energies were calculated and folded with emissions of 1252 radionuclides addressed in ICRP Publication 107 to determine equivalent and effective dose rate coefficients. The MCNP6 radiation transport code was used for organ dose ratemore » calculations for photons and the contribution of electrons to skin dose rate was derived using point-kernels. Bremsstrahlung and annihilation photons of positron emission were evaluated as discrete photons. As a result, the coefficients calculated in this work compare favorably to those reported in the US Federal Guidance Report 12 as well as by other authors who employed voxel phantoms for similar exposure scenarios.« less
New potential energy surface for the HCS{sup +}–He system and inelastic rate coefficients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dubernet, Marie-Lise; Quintas-Sánchez, Ernesto; Tuckey, Philip

2015-07-28

A new high quality potential energy surface is calculated at a coupled-cluster single double triple level with an aug-cc-pV5Z basis set for the HCS{sup +}–He system. This potential energy surface is used in low energy quantum scattering calculations to provide a set of (de)-excitation cross sections and rate coefficients among the first 20 rotational levels of HCS{sup +} by He in the range of temperature from 5 K to 100 K. The paper discusses the impact of the new ab initio potential energy surface on the cross sections at low energy and provides a comparison with the HCO{sup +}–He system.more » The HCS{sup +}–He rate coefficients for the strongest transitions differ by factors of up to 2.5 from previous rate coefficients; thus, analysis of astrophysical spectra should be reconsidered with the new rate coefficients.« less
Magnetic Damping For Maglev

DOE PAGES

Zhu, S.; Cai, Y.; Rote, D. M.; ...

1998-01-01

Magnetic damping is one of the important parameters that control the response and stability of maglev systems. An experimental study to measure magnetic damping directly is presented. A plate attached to a permanent magnet levitated on a rotating drum was tested to investigate the effect of various parameters, such as conductivity, gap, excitation frequency, and oscillation amplitude, on magnetic damping. The experimental technique is capable of measuring all of the magnetic damping coefficients, some of which cannot be measured indirectly.
IEEE Conference Record of 1980 Fourteenth Pulse Power Modulator Symposium, 3-5 June 1980.

DTIC Science & Technology

1980-01-01

attachment and generation coefficients, usually given volume can control the velocity of the streamer phase as a function of E/P. Data on experimentally ...more foils could be used if desired. The mechanical design for the electron beau Experimental Program controlled switch has two competing requirenmts...deter- mine the effect of the plasma conditioning as compared to the control tests. 2W C C TABLE I: SUMMARY OF EXPERIMENTAL PROCEDURE • ur EIIEIT
Results of Two Free-fall Experiments on Flutter of Thin Unswept Wings in the Transonic Speed Range

NASA Technical Reports Server (NTRS)

Lauten, William T , Jr; Nelson, Herbert C

1957-01-01

Results of four thin, unswept, flutter airfoils attached to two freely falling bodies are reported. Two airfoils fluttered at a Mach number of 0.85, a third airfoil fluttered at a Mach number of 1.03, and a fourth fluttered at a Mach number of 1.07. Results of calculations of flutter speed using incompressible and compressible air-force coefficients, including a Mach number of 1.0, are presented.
Securing Bearing Races To Turbopump Shafts

NASA Technical Reports Server (NTRS)

Blount, Dale H.

1990-01-01

Proposed method of attaching inner race of roller bearing to shaft prevents loosening now caused by difference between coefficients of thermal expansion of race and shaft materials. Intended for cryogenic turbopump in which race made of 440C stainless-steel alloy and shaft made of Inconel(R) 100 nickel alloy. Flanges of race replaced by tension bands that shrink faster as they are cooled. Tension band engages race on slightly sloping surface so axial forces do not dislodge it.
Dielectronic and Trielectronic Recombination Rate Coefficients of Be-like Ar14+

NASA Astrophysics Data System (ADS)

Huang, Z. K.; Wen, W. Q.; Xu, X.; Mahmood, S.; Wang, S. X.; Wang, H. B.; Dou, L. J.; Khan, N.; Badnell, N. R.; Preval, S. P.; Schippers, S.; Xu, T. H.; Yang, Y.; Yao, K.; Xu, W. Q.; Chuai, X. Y.; Zhu, X. L.; Zhao, D. M.; Mao, L. J.; Ma, X. M.; Li, J.; Mao, R. S.; Yuan, Y. J.; Wu, B.; Sheng, L. N.; Yang, J. C.; Xu, H. S.; Zhu, L. F.; Ma, X.

2018-03-01

Electron–ion recombination of Be-like 40Ar14+ has been measured by employing the electron–ion merged-beams method at the cooler storage ring CSRm. The measured absolute recombination rate coefficients for collision energies from 0 to 60 eV are presented, covering all dielectronic recombination (DR) resonances associated with 2s 2 → 2s2p core transitions. In addition, strong trielectronic recombination (TR) resonances associated with 2s 2 → 2p 2 core transitions were observed. Both DR and TR processes lead to series of peaks in the measured recombination spectrum, which have been identified by the Rydberg formula. Theoretical calculations of recombination rate coefficients were performed using the state-of-the-art multi-configuration Breit–Pauli atomic structure code AUTOSTRUCTURE to compare with the experimental results. The plasma rate coefficients for DR+TR of Ar14+ were deduced from the measured electron–ion recombination rate coefficients in the temperature range from 103 to 107 K, and compared with calculated data from the literature. The experimentally derived plasma rate coefficients are 60% larger and 30% lower than the previously recommended atomic data for the temperature ranges of photoionized plasmas and collisionally ionized plasmas, respectively. However, good agreement was found between experimental results and the calculations by Gu and Colgan et al. The plasma rate coefficients deduced from experiment and calculated by the current AUTOSTRUCTURE code show agreement that is better than 30% from 104 to 107 K. The present results constitute a set of benchmark data for use in astrophysical modeling.
Coefficient of friction and wear rate effects of different composite nanolubricant concentrations on Aluminium 2024 plate

NASA Astrophysics Data System (ADS)

Zawawi, N. N. M.; Azmi, W. H.; Redhwan, A. A. M.; Sharif, M. Z.

2017-10-01

Wear of sliding parts and operational machine consistency enhancement can be avoided with good lubrication. Lubrication reduce wear between two contacting and sliding surfaces and decrease the frictional power losses in compressor. The coefficient of friction and wear rate effects study were carried out to measure the friction and anti-wear abilities of Al2O3-SiO2 composite nanolubricants a new type of compressor lubricant to enhanced the compressor performances. The tribology test rig employing reciprocating test conditions to replicate a piston ring contact in the compressor was used to measure the coefficient of friction and wear rate. Coefficient of friction and wear rate effects of different Al2O3-SiO2/PAG composite nanolubricants of Aluminium 2024 plate for 10-kg load at different speed were investigated. Al2O3 and SiO2 nanoparticles were dispersed in the Polyalkylene Glycol (PAG 46) lubricant using two-steps method of preparation. The result shows that the coefficient friction and wear rate of composite nanolubricants decreased compared to pure lubricant. The maximum reduction achievement for friction of coefficient and wear rate by Al2O3-SiO2 composite nanolubricants by 4.78% and 12.96% with 0.06% volume concentration. Therefore, 0.06% volume concentration is selected as the most enhanced composite nanolubricants with effective coefficient of friction and wear rate reduction compared to other volume concentrations. Thus, it is recommended to be used as the compressor lubrication to enhanced compressor performances.
Do Dog Behavioral Characteristics Predict the Quality of the Relationship between Dogs and Their Owners?

PubMed

Hoffman, Christy L; Chen, Pan; Serpell, James A; Jacobson, Kristen C

This paper explores whether dog behavioral characteristics predict the quality of the relationship between dogs and their owners (i.e., owner attachment to dog), and whether relations between dog behavior and owner attachment are moderated by demographic characteristics. In this study, N = 92 children and N = 60 adults from 60 dog-owning families completed questionnaires about their attachment to their pet dog, their level of responsibility for that dog, and their general attitudes toward pets. They also rated their dogs on observable behavioral characteristics. Individuals who held positive attitudes about pets and who provided much of their dog's care reported stronger attachments to their dogs. The strength of owners' attachments to their dogs was associated with dog trainability and separation problems. Relationships between owner attachment and both dog excitability and attention-seeking behavior were further moderated by demographic characteristics: for Caucasians but not for non-Caucasians, dog excitability was negatively associated with owner attachment to dog; and for adults, dog attention-seeking behavior was positively associated with owner attachment, but children tended to be highly attached to their dogs, regardless of their dogs' attention-seeking behaviors. This study demonstrates that certain dog behavioral traits are indeed associated with the strength of owners' attachments to their dogs.
Top electrode size effects in the piezoresponse force microscopy of piezoelectric thin films attached to a rigid substrate

NASA Astrophysics Data System (ADS)

Wang, J. H.

2017-10-01

In order to avoid the highly concentrated electric field induced beneath the sharp tip, the technique using a top coating electrode in the piezoresponse force microscopy (PFM) has been developed to detect the piezoelectric coefficients. Reliable theory should be erected to explain the broadly reported top electrode size effects and relate the responses with material constants. In this paper, the surface displacement, electric potential inside the film, electric charge and effective piezoelectric coefficient are expressed as a set of integral equations. Analytical solutions are obtained for two limiting cases, i.e., half space (HS) and infinitely thin film (IT). The effective piezoelectric coefficient of the HS case is proved to be the same as that from the PFM of a piezoelectric half plane without a top coating. For the IT case, it is identical to the well-known piezoelectric coefficient result of piezoelectric thin film clamped between flat rigid electrodes subject to homogeneous external electric field. For PZT4 thin layer, numerical results reveal that the surface displacement obviously decreases and the electric potential distributions inside the film become more and more homogeneous as the electrode radius to film thickness ratio (a/t) enlarges. The electric charge dramatically increases while the effective piezoelectric coefficient evidently decreases and they both transfer from the HS solutions to the IT results when a/t varies from 0.001 to 20. The transition occurs at about a/t = 1 in agreement with the experimental observations. A critical top electrode size, i.e., a/t > 10, is obtained and applicable to other piezoelectric materials. Under such circumstances, one can readily gain the piezoelectric coefficients e 33, d 33 and the dielectric coefficient {\\in }33 if other mechanical coefficients and one piezoelectric constant are known a prior.
Rate Constants for Fine-Structure Excitations in O - H Collisions with Error Bars Obtained by Machine Learning

NASA Astrophysics Data System (ADS)

Vieira, Daniel; Krems, Roman

2017-04-01

Fine-structure transitions in collisions of O(3Pj) with atomic hydrogen are an important cooling mechanism in the interstellar medium; knowledge of the rate coefficients for these transitions has a wide range of astrophysical applications. The accuracy of the theoretical calculation is limited by inaccuracy in the ab initio interaction potentials used in the coupled-channel quantum scattering calculations from which the rate coefficients can be obtained. In this work we use the latest ab initio results for the O(3Pj) + H interaction potentials to improve on previous calculations of the rate coefficients. We further present a machine-learning technique based on Gaussian Process regression to determine the sensitivity of the rate coefficients to variations of the underlying adiabatic interaction potentials. To account for the inaccuracy inherent in the ab initio calculations we compute error bars for the rate coefficients corresponding to 20% variation in each of the interaction potentials. We obtain these error bars by fitting a Gaussian Process model to a data set of potential curves and rate constants. We use the fitted model to do sensitivity analysis, determining the relative importance of individual adiabatic potential curves to a given fine-structure transition. NSERC.
Measurement of diffusion coefficients important in modeling the absorption rate of carbon dioxide into aqueous N-methyldiethanolamine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowley, R.L.; Adams, M.E.; Marshall, T.L.

1997-03-01

Natural gas processors use amine treating processes to remove the acid gases H{sub 2}S and CO{sub 2} from gas streams. Absorption rates of gaseous CO{sub 2} into aqueous N-methyldiethanolamine (MDEA) solutions were measured in a quiescent, inverted-tube diffusiometer by monitoring the rate of pressure drop. The absorption rate was found to be insensitive to the diffusion coefficient of CO{sub 2} in solution but very sensitive to the diffusion rate of bicarbonate and protonated MDEA ions. Evidence also suggested that chemical reaction equilibrium is rapid relative to diffusion. A numerical model was developed on the basis of these observations. The modelmore » was used to regress diffusion coefficients of bicarbonate and protonated amine, which must be equivalent by electroneutrality arguments, from measured absorption rates. Complete modeling of the absorption process also required data for the diffusion coefficient of MDEA in water. These were measured using a Taylor dispersion apparatus. CO{sub 2} absorption rates and diffusion coefficients of bicarbonate and protonated MDEA were obtained at 298.2 K and 318.2 K in solutions containing 20, 35, and 50 mass % MDEA in water.« less
Interdye Hole Transport Accelerates Recombination in Dye Sensitized Mesoporous Films.

PubMed

Moia, Davide; Szumska, Anna; Vaissier, Valérie; Planells, Miquel; Robertson, Neil; O'Regan, Brian C; Nelson, Jenny; Barnes, Piers R F

2016-10-12

Charge recombination between oxidized dyes attached to mesoporous TiO 2 and electrons in the TiO 2 was studied in inert electrolytes using transient absorption spectroscopy. Simultaneously, hole transport within the dye monolayers was monitored by transient absorption anisotropy. The rate of recombination decreased when hole transport was inhibited selectively, either by decreasing the dye surface coverage or by changing the electrolyte environment. From Monte Carlo simulations of electron and hole diffusion in a particle, modeled as a cubic structure, we identify the conditions under which hole lifetime depends on the hole diffusion coefficient for the case of normal (disorder free) diffusion. From simulations of transient absorption and transient absorption anisotropy, we find that the rate and the dispersive character of hole transport in the dye monolayer observed spectroscopically can be explained by incomplete coverage and disorder in the monolayer. We show that dispersive transport in the dye monolayer combined with inhomogeneity in the TiO 2 surface reactivity can contribute to the observed stretched electron-hole recombination dynamics and electron density dependence of hole lifetimes. Our experimental and computational analysis of lateral processes at interfaces can be applied to investigate and optimize charge transport and recombination in solar energy conversion devices using electrodes functionalized with molecular light absorbers and catalysts.
Dissociative recombination of HCl+, H2Cl+, DCl+, and D2Cl+ in a flowing afterglow

NASA Astrophysics Data System (ADS)

Wiens, Justin P.; Miller, Thomas M.; Shuman, Nicholas S.; Viggiano, Albert A.

2016-12-01

Dissociative recombination of electrons with HCl+, H2Cl+, DCl+, and D2Cl+ has been measured under thermal conditions at 300, 400, and 500 K using a flowing afterglow-Langmuir probe apparatus. Measurements for HCl+ and DCl+ employed the variable electron and neutral density attachment mass spectrometry (VENDAMS) method, while those for H2Cl+ and D2Cl+ employed both VENDAMS and the more traditional technique of monitoring electron density as a function of reaction time. At 300 K, HCl+ and H2Cl+ recombine with kDR = 7.7±2.14.5 × 10-8 cm3 s-1 and 2.6 ± 0.8 × 10-7 cm3 s-1, respectively, whereas D2Cl+ is roughly half as fast as H2Cl+ with kDR = 1.1 ± 0.3 × 10-7 cm3 s-1 (2 σ confidence intervals). DCl+ recombines with a rate coefficient below the approximate detection limit of the method (≲5 × 10-8 cm3 s-1) at all temperatures. Relatively slow dissociative recombination rates have been speculated to be responsible for the large HCl+ and H2Cl+ abundances in interstellar clouds compared to current astrochemical models, but our results imply that the discrepancy must originate elsewhere.
Preferential attachment in evolutionary earthquake networks

NASA Astrophysics Data System (ADS)

Rezaei, Soghra; Moghaddasi, Hanieh; Darooneh, Amir Hossein

2018-04-01

Earthquakes as spatio-temporal complex systems have been recently studied using complex network theory. Seismic networks are dynamical networks due to addition of new seismic events over time leading to establishing new nodes and links to the network. Here we have constructed Iran and Italy seismic networks based on Hybrid Model and testified the preferential attachment hypothesis for the connection of new nodes which states that it is more probable for newly added nodes to join the highly connected nodes comparing to the less connected ones. We showed that the preferential attachment is present in the case of earthquakes network and the attachment rate has a linear relationship with node degree. We have also found the seismic passive points, the most probable points to be influenced by other seismic places, using their preferential attachment values.
Change in heart rate variability after the adult attachment interview in dissociative patients.

PubMed

Farina, Benedetto; Speranza, Anna Maria; Imperatori, Claudio; Quintiliani, Maria Isabella; Della Marca, Giacomo

2015-01-01

The aim of this study was to assess heart rate variability (HRV) in individuals with dissociative disorders (DD) before and after the Adult Attachment Interview (AAI). Electrocardiograms were recorded before, during, and after the AAI in 13 individuals with DD and 13 healthy participants matched for age and gender. Significant change in HRV was observed only in the DD group. After the AAI, those with DD showed significant increases in the low frequency/high frequency ratio (pre-AAI = 1.91 ± 1.19; post-AAI = 4.03 ± 2.40; Wilcoxon test = -2.76, p = .005). Our results suggest that the retrieval of childhood attachment experiences in individuals with DD is associated with a change in HRV patterns that could reflect the emotion dysregulation of dissociative psychopathological processes.
Validation of the Scale of Preferences and Expectations in Close Interpersonal Relationships (EPERIC).

PubMed

Fontanil, Yolanda; Ezama, Esteban; Alonso, Yolanda

2013-01-01

The most commonly used instruments for assessing adult attachment have shown differing combinations of items and divergences in the resulting sub-scales. This study presents the Scale of Preferences and Expectations in Close Interpersonal Relationships ( Escala de Preferencias y Expectativas en las Relaciones Interpersonales Cercanas, EPERIC), made up of 22 items, and based upon the Relationship Scales Questionnaire (RSQ) of Griffin and Bartholomew. Exploratory and confirmatory factorial analyses (EFA and CFA) were undertaken using data from a sample of 594 people. Factor analysis distinguishes three sub-scales: Fear of rejection or abandonment , Desire for closeness and Preference for independence , which explains 42.78% of the total variance. The alpha coefficients reveal a high internal consistency of the instrument and its sub-scales. Regarding validity, CFA showed an adequate fit for the trifactorial solution, and the expected correlations with other instruments for assessing attachment style in adults were found. EPERIC is also suitable for predicting affective states and psychological well-being. The EPERIC is a potentially useful and valid instrument for research and clinical purposes. The discussion focuses on the fact that our results support a model of three factors rather than two, as is usual in studies on adult attachment.
Attachment Contexts of Adolescent Friendship and Romance

ERIC Educational Resources Information Center

Miller, Judi Beinstein; Hoicowitz, Tova

2004-01-01

The purpose of this study was to compare memories of attachments to parents, friends, and romantic partners in relation to the maintenance of high school friendships and romantic relationships. College students recorded the length of their friendships and romantic relationships during high school and rated the quality of each. They also rated…

Attachment-Based Family Therapy: "Adherence" and Differentiation

ERIC Educational Resources Information Center

Diamond, Gary M.; Diamond, Guy S.; Hogue, Aaron

2007-01-01

This study examined the fidelity of attachment-based family therapy (ABFT) for depressed adolescents. Trained observers used the therapist behavior rating scale (3rd version) to code therapist behaviors in 45 sessions of ABFT and 45 sessions each from two empirically based treatments for adolescent substance abusers: multidimensional family…
The role of intra-NAPL diffusion on mass transfer from MGP residuals

NASA Astrophysics Data System (ADS)

Shafieiyoun, Saeid; Thomson, Neil R.

2018-06-01

An experimental and computational study was performed to investigate the role of multi-component intra-NAPL diffusion on NAPL-water mass transfer. Molecular weight and the NAPL component concentrations were determined to be the most important parameters affecting intra-NAPL diffusion coefficients. Four NAPLs with different viscosities but the same quantified mass were simulated. For a spherical NAPL body, a combination of NAPL properties and interphase mass transfer rate can result in internal diffusion limitations. When the main intra-NAPL diffusion coefficients are in the range of self-diffusion coefficients (10-5 to 10-6 cm2/s), dissolution is not limited by internal diffusion except for high mass transfer rate coefficients (>180 cm/day). For a complex and relatively high viscous NAPL (>50 g/(cm s)), smaller intra-NAPL diffusion coefficients (<10-8) are expected and even low mass transfer rate coefficients ( 6 cm/day) can result in diffusion-limited dissolution.
Supersonic, nonlinear, attached-flow wing design for high lift with experimental validation

NASA Technical Reports Server (NTRS)

Pittman, J. L.; Miller, D. S.; Mason, W. H.

1984-01-01

Results of the experimental validation are presented for the three dimensional cambered wing which was designed to achieve attached supercritical cross flow for lifting conditions typical of supersonic maneuver. The design point was a lift coefficient of 0.4 at Mach 1.62 and 12 deg angle of attack. Results from the nonlinear full potential method are presented to show the validity of the design process along with results from linear theory codes. Longitudinal force and moment data and static pressure data were obtained in the Langley Unitary Plan Wind Tunnel at Mach numbers of 1.58, 1.62, 1.66, 1.70, and 2.00 over an angle of attack range of 0 to 14 deg at a Reynolds number of 2.0 x 10 to the 6th power per foot. Oil flow photographs of the upper surface were obtained at M = 1.62 for alpha approx. = 8, 10, 12, and 14 deg.
Physical model and experimental results of cathode erosion related to power supply ripple

NASA Technical Reports Server (NTRS)

Harris, W. J.; O'Hair, E. A.; Hatfield, L. L.; Kristiansen, M.

1992-01-01

This paper discusses the physical effects of power supply ripple on cathode erosion and cathode arc attachment in a water-cooled, 30 kW nitrogen arcjet. Experimental results are presented for 2 percent thoriated tungsten, which show that the long-term cathode erosion rate is a decreasing function of current ripple over the range 1-13 percent. Above this range, the cathode discharge becomes unstable, and the erosion rate rapidly increases. A qualitative model of this effect is given in terms of a magnetically induced radial motion of the arc column, and an overall increase in the cathode spot radius due to the higher peak current associated with higher ripple. The most important effect of power supply ripple is therefore shown to be its ability to collectively drive the cathode attachment away from the cathode center. This leads to an increase in the cathode attachment area, and a subsequent decrease in the cathode erosion rate.
Comparison of Monoenergetic Photon Organ Dose Rate Coefficients for the Female Stylized and Voxel Phantoms Submerged in Air

DOE PAGES

Hiller, Mauritius; Dewji, Shaheen Azim

2017-02-16

Dose rate coefficients computed using the International Commission on Radiological Protection (ICRP) reference adult female voxel phantom were compared with values computed using the Oak Ridge National Laboratory (ORNL) adult female stylized phantom in an air submersion exposure geometry. This is a continuation of previous work comparing monoenergetic organ dose rate coefficients for the male adult phantoms. With both the male and female data computed, effective dose rate as defined by ICRP Publication 103 was compared for both phantoms. Organ dose rate coefficients for the female phantom and ratios of organ dose rates for the voxel and stylized phantoms aremore » provided in the energy range from 30 to 5 MeV. Analysis of the contribution of the organs to effective dose is also provided. Lastly, comparison of effective dose rates between the voxel and stylized phantoms was within 8% at 100 keV and is <5% between 200 and 5000 keV.« less
Comparison of Monoenergetic Photon Organ Dose Rate Coefficients for the Female Stylized and Voxel Phantoms Submerged in Air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hiller, Mauritius; Dewji, Shaheen Azim

Dose rate coefficients computed using the International Commission on Radiological Protection (ICRP) reference adult female voxel phantom were compared with values computed using the Oak Ridge National Laboratory (ORNL) adult female stylized phantom in an air submersion exposure geometry. This is a continuation of previous work comparing monoenergetic organ dose rate coefficients for the male adult phantoms. With both the male and female data computed, effective dose rate as defined by ICRP Publication 103 was compared for both phantoms. Organ dose rate coefficients for the female phantom and ratios of organ dose rates for the voxel and stylized phantoms aremore » provided in the energy range from 30 to 5 MeV. Analysis of the contribution of the organs to effective dose is also provided. Lastly, comparison of effective dose rates between the voxel and stylized phantoms was within 8% at 100 keV and is <5% between 200 and 5000 keV.« less
Passive air sampling theory for semivolatile organic compounds.

PubMed

Bartkow, Michael E; Booij, Kees; Kennedy, Karen E; Müller, Jochen F; Hawker, Darryl W

2005-07-01

The mathematical modelling underlying passive air sampling theory can be based on mass transfer coefficients or rate constants. Generally, these models have not been inter-related. Starting with basic models, the exchange of chemicals between the gaseous phase and the sampler is developed using mass transfer coefficients and rate constants. Importantly, the inter-relationships between the approaches are demonstrated by relating uptake rate constants and loss rate constants to mass transfer coefficients when either sampler-side or air-side resistance is dominating chemical exchange. The influence of sampler area and sampler volume on chemical exchange is discussed in general terms and as they relate to frequently used parameters such as sampling rates and time to equilibrium. Where air-side or sampler-side resistance dominates, an increase in the surface area of the sampler will increase sampling rates. Sampling rates are not related to the sampler/air partition coefficient (K(SV)) when air-side resistance dominates and increase with K(SV) when sampler-side resistance dominates.
Self-concept in institutionalized children with disturbed attachment: The mediating role of exploratory behaviours.

PubMed

Vacaru, V S; Sterkenburg, P S; Schuengel, C

2018-05-01

Self-concept is seen as both an outcome of sociocognitive and emotional development, and a factor in social and mental health outcomes. Although the contribution of attachment experiences to self-concept has been limited to quality of primary attachment relationships, little is known of the effects of disturbed attachment on self-concept in institutionalized children. Thus, the current study examined associations between disturbed attachment behaviours in institutionalized children and self-concept, testing limited exploration as an explanatory factor. Thirty-three institutionalized children, aged 4-12, participated in a multimethod and multi-informant assessment of disturbed attachment behaviours (i.e., Disturbances of Attachment Interview and Behavioral Signs of Disturbed Attachment in Young Children), self-concept (i.e., Pictorial Scale of Perceived Competence and Social Acceptance for Young Children), and exploratory behaviours (i.e., Student Exploratory Behaviours Observation Scale). Analyses were conducted using bootstrapping techniques. Global self-concept converged with teacher-rated children's self-concept, except for physical competence domain. Disturbed attachment behaviours were identified in 62.5% of the children, and this was associated with lower levels of exploration and lower scores on self-concept, compared with children without disturbed attachment behaviours. Furthermore, exploratory behaviours mediated the effects of disturbed attachment behaviours on self-concept. Institution-reared children with disturbed attachment behaviours were likely to have a negative perception of self and one's own competences. Limited exploratory behaviours explained this linkage. Targeting disordered attachment in children reared in institutions and their caregivers should become a high priority as a means for preventing socioemotional development issues. © 2017 John Wiley & Sons Ltd.
Species-to-species rate coefficients for the H3+ + H2 reacting system

NASA Astrophysics Data System (ADS)

Sipilä, O.; Harju, J.; Caselli, P.

2017-10-01

Aims: We study whether or not rotational excitation can make a large difference to chemical models of the abundances of the H3+ isotopologs, including spin states, in physical conditions corresponding to starless cores and protostellar envelopes. Methods: We developed a new rate coefficient set for the chemistry of the H3+ isotopologs, allowing for rotational excitation, using previously published state-to-state rate coefficients. These new so-called species-to-species rate coefficients are compared with previously-used ground-state-to-species rate coefficients by calculating chemical evolution in variable physical conditions using a pseudo-time-dependent chemical code. Results: We find that the new species-to-species model produces different results to the ground state-to-species model at high density and toward increasing temperatures (T> 10 K). The most prominent difference is that the species-to-species model predicts a lower H3+ deuteration degree at high density owing to an increase of the rate coefficients of endothermic reactions that tend to decrease deuteration. For example at 20 K, the ground-state-to-species model overestimates the abundance of H2D+ by a factor of about two, while the abundance of D3+ can differ by up to an order of magnitude between the models. The spin-state abundance ratios of the various H3+ isotopologs are also affected, and the new model better reproduces recent observations of the abundances of ortho and para H2D+ and D2H+. The main caveat is that the applicability regime of the new rate coefficients depends on the critical densities of the various rotational transitions which vary with the abundances of the species and the temperature in dense clouds. Conclusions: The difference in the abundances of the H3+ isotopologs predicted by the species-to-species and ground state-to-species models is negligible at 10 K corresponding to physical conditions in starless cores, but inclusion of the excited states is very important in studies of deuteration at higher temperatures, for example in protostellar envelopes. The species-to-species rate coefficients provide a more realistic approach to the chemistry of the H3+ isotopologs than the ground-state-to-species rate coefficients do, and so the former should be adopted in chemical models describing the chemistry of the H3+ + H2 reacting system.
Fine and hyperfine collisional excitation of C6H by He

NASA Astrophysics Data System (ADS)

Walker, Kyle M.; Lique, François; Dawes, Richard

2018-01-01

Hydrogenated carbon chains have been detected in interstellar and circumstellar media and accurate modelling of their abundances requires collisional excitation rate coefficients with the most abundant species. Among them, the C6H molecule is one of the most abundant towards many lines of sight. Hence, we determined fine and hyperfine-resolved rate coefficients for the excitation of C6H(X2Π) due to collisions with He. We present the first interaction potential energy surface for the C6H-He system, obtained from highly correlated ab initio calculations and characterized by a large anisotropy due to the length of the molecule. We performed dynamical calculations for transitions among the first fine structure levels (up to J = 30.5) of both spin-orbit manifolds of C6H using the close-coupling method, and rate coefficients are determined for temperatures ranging from 5 to 100 K. The largest rate coefficients for even ΔJ transitions conserve parity, while parity-breaking rate coefficients are favoured for odd ΔJ. Spin-orbit changing rate coefficients are several orders of magnitude lower than transitions within a single manifold. State-to-state hyperfine-resolved cross-sections for the first levels (up to J = 13.5) in the Ω = 3/2 spin-orbit manifold are deduced using recoupling techniques. Rate coefficients are obtained and the propensity rule ΔJ = ΔF is seen. These new data will help determine the abundance of C6H in astrophysical environments such as cold dense molecular clouds, star-forming regions and circumstellar envelopes, and will help in the interpretation of the puzzling C6H-/C6H abundance ratios deduced from observations.
Thermal electron attachment to van der Waals molecules containing O/sub 2/

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huo, W.M.; Fessenden, R.W.; Bauschlicher C.W. Jr.

1984-12-15

Calculations on O/sub 2/xN/sub 2/ and O/sup -//sub 2/xN/sub 2/ have been carried out to explain the large enhancement in the attachment rate of thermal electrons found in van der Waals molecules containing O/sub 2/. Two geometries, T-shape and linear, are used. SCF wave functions are used to represent both the neutral molecule and the ion. The incoming electron is approximated by a plane wave. The width is determined using a shielded polarization potential. The effect of additional vibrational structures of the van der Waals molecule on the attachment process is investigated by studying the O/sub 2/--N/sub 2/ stretching modemore » using Lennard-Jones potentials. Symmetry breaking, which allows the molecule to attach a p wave electron, is shown to play a primary role. The lowering of resonance energy, due to a deeper Lennard-Jones potential of O/sup -//sub 2/xN/sub 2/ in comparison with O/sub 2/xN/sub 2/, furthers the enhancement. The calculated attachment rate is comparable to that determined by Shimamori and Fessenden, but differs from the recent values obtained by Toriumi and Hatano, who used a different set of reactions to interpret their data.« less
Enhancing attachment security in the infants of women in a jail-diversion program.

PubMed

Cassidy, Jude; Ziv, Yair; Stupica, Brandi; Sherman, Laura J; Butler, Heidi; Karfgin, Andrea; Cooper, Glen; Hoffman, Kent T; Powell, Bert

2010-07-01

Pregnant female offenders face multiple adversities that make successful parenting difficult. As a result, their children are at risk of developing insecure attachment and attachment disorganization, both of which are associated with an increased likelihood of poor developmental outcomes. We evaluated the outcomes of participants in Tamar's Children, a 15-month jail-diversion intervention for pregnant, nonviolent offenders with a history of substance abuse. All women received extensive wrap-around social services as well as the Circle of Security Perinatal Protocol (Cooper, Hoffman, & Powell, 2003). We present data on 20 women and their infants who completed the full dosage of treatment (a residential-living phase from pregnancy until infant age six months and community-living phase until 12 months). Results indicated that (1) program infants had rates of attachment security and attachment disorganization comparable to rates typically found in low-risk samples (and more favorable than those typically found in high-risk samples); (2) program mothers had levels of maternal sensitivity comparable to mothers in an existing community comparison group; and (3) improvement over time emerged for maternal depressive symptomatology, but not other aspects of maternal functioning. Given the lack of a randomized control group, results are discussed in terms of the exploratory, program-development nature of the study.
Determination of the N2 recombination rate coefficient in the ionosphere

NASA Technical Reports Server (NTRS)

Orsini, N.; Torr, D. G.; Brinton, H. C.; Brace, L. H.; Hanson, W. B.; Hoffman, J. H.; Nier, A. O.

1977-01-01

Measurements of aeronomic parameters made by the Atmosphere Explorer-C satellite are used to determine the recombination rate coefficient of N2(+) in the ionosphere. The rate is found to increase significantly with decreasing electron density. Values obtained range from approximately 1.4 x 10 to the -7th to 3.8 x 10 to the -7th cu cm/sec. This variation is explained in a preliminary way in terms of an increase in the rate coefficient with vibrational excitation. Thus, high electron densities depopulate high vibrational levels reducing the effective recombination rate, whereas, low electron densities result in an enhancement in the population of high vibrational levels, thus, increasing the effective recombination rate.
Rotordynamic Forces Developed by Labyrinth Seals

DTIC Science & Technology

1984-11-01

the prediction of leakage and the rotordynamic coefficients of Eq. (1) for labyrinth seals . A copy of reference DI) is attached. In comparison to... Leakage of Steam Through Labyrinth Glands," Trans. ASME, Vol. 57, 1935, pp. 115-122. 16. John, E. A. Jamea, Gas Dynamios, Wylie, 1979. -19- • ]{ o -Cr...Quadratic-Upstream Di iferemcing in Uigh Reynolds Number Illiptic a. Xgli. A.. ’"the Leakage of Steam Through Labyrinth flows," of P ohAa. ab o.. l 9
Reynolds Number Effects on Thrust Coefficients and PIV for Flapping Wing Micro Air Vehicles

DTIC Science & Technology

2012-03-09

flapper and smallest gear attached to the drive shaft from the motor. Lastly, passive rotation stops were designed and printed using the Objet Eden 500V...for different flapping mechanisms are also compared to a rotating propeller with the goal of elucidating the design trade space between rotorcraft and...flapping wings at Reynolds numbers less than 100,000. One flapping-wing mechanism was designed to incorporate a coupled 4-bar planar and 4-bar
Ion Storage Ring Measurements of Low Temperature Dielectronic Recombination Rate Coefficients for Modeling X-Ray Photoionized Cosmic Plasmas

NASA Technical Reports Server (NTRS)

Savin, D. W.; Gwinner, G.; Schwalm, D.; Wolf, A.; Mueller, A.; Schippers, S.

2002-01-01

Low temperature dielectronic recombination (DR) is the dominant recombination mechanism for most ions in X-ray photoionized cosmic plasmas. Reliably modeling and interpreting spectra from these plasmas requires accurate low temperature DR rate Coefficients. Of particular importance are the DR rate coefficients for the iron L-shell ions (Fe XVII-Fe XXIV). These ions are predicted to play an important role in determining the thermal structure and line emission of X-ray photoionized plasmas, which form in the media surrounding accretion powered sources such as X-ray binaries (XRBs), active galactic nuclei (AGN), and cataclysmic variables (Savin et al., 2000). The need for reliable DR data of iron L-shell ions has become particularly urgent after the launches of Chandra and XMM-Newton. These satellites are now providing high-resolution X-ray spectra from a wide range of X-ray photoionized sources. Interpreting the spectra from these sources requires reliable DR rate coefficients. However, at the temperatures relevant, for X-ray photoionized plasmas, existing theoretical DR rate coefficients can differ from one another by factors of two to orders of magnitudes.
Hyperfine excitation of OH+ by H

NASA Astrophysics Data System (ADS)

Lique, François; Bulut, Niyazi; Roncero, Octavio

2016-10-01

The OH+ ions are widespread in the interstellar medium and play an important role in the interstellar chemistry as they act as precursors to the H2O molecule. Accurate determination of their abundance rely on their collisional rate coefficients with atomic hydrogen and electrons. In this paper, we derive OH+-H fine and hyperfine-resolved rate coefficients by extrapolating recent quantum wave packet calculations for the OH+ + H collisions, including inelastic and exchange processes. The extrapolation method used is based on the infinite order sudden approach. State-to-state rate coefficients between the first 22 fine levels and 43 hyperfine levels of OH+ were obtained for temperatures ranging from 10 to 1000 K. Fine structure-resolved rate coefficients present a strong propensity rule in favour of Δj = ΔN transitions. The Δj = ΔF propensity rule is observed for the hyperfine transitions. The new rate coefficients will help significantly in the interpretation of OH+ spectra from photon-dominated region (PDR), and enable the OH+ molecule to become a powerful astrophysical tool for studying the oxygen chemistry.
Attachment in young children with incarcerated fathers.

PubMed

Poehlmann-Tynan, Julie; Burnson, Cynthia; Runion, Hilary; Weymouth, Lindsay A

2017-05-01

The present study examined young children's attachment behaviors during paternal incarceration and reported on initial validity of a new measure used to rate children's attachment-related behaviors and emotions during visits in a corrections setting. Seventy-seven children, age 2 to 6 years, and their jailed fathers and current caregivers participated in the home visit portion of the study, whereas 28 of these children participated in the jail visit. The results indicated that 27% of children witnessed the father's crime and 22% of children witnessed the father's arrest, with most children who witnessed these events exhibiting extreme distress; children who witnessed these events were more likely to have insecure attachments to their caregivers. Consistent with attachment theory and research, caregivers who exhibited more sensitivity and responsivity during interactions with children and those who provided more stimulating, responsive, learning-oriented home environments had children who were more likely to have secure attachments (measured with the Attachment Q-Sort). We also found preliminary evidence for the validity of our new measure, the Jail Prison Observation Checklist, in that children's attachment-related behaviors and emotions during the jail visit correlated with their attachment security observed in the home. Our observations indicate that, in certain contexts, noncontact visits with incarcerated parents can be stressful for children and that children's caregivers may play a significant role during these visits.
Attachment Security Mediates the Longitudinal Association Between Child-Parent Psychotherapy and Peer Relations for Toddlers of Depressed Mothers

PubMed Central

Guild, Danielle J.; Toth, Sheree L.; Handley, Elizabeth D.; Rogosch, Fred A.; Cicchetti, Dante

2017-01-01

Numerous investigations have demonstrated that Child-Parent Psychotherapy (CPP) promotes secure attachment between mothers and offspring. However, the role of post-intervention attachment security as it relates to long-term child outcomes has never been evaluated. The present study therefore examined post-intervention attachment status as a mediator of the association between CPP for depressed mothers and their offspring and subsequent peer relations among offspring. Depressed mothers and their toddlers were randomized to receive CPP (n = 45) or to a control group (DC; n = 55). A prior investigation with this sample indicated that offpring who received CPP attained significantly higher rates of secure attachment post-intervention, wheras insecure attachment continued to predominate for offspring in the DC group. The present study examined follow-up data of teachers’ reports on participants’ competence with classroom peers when they were approximately 9 years old. Findings indicated that children who received CPP were more likely to evidence secure attachments at post-intervention, which in turn was associated with more positive peer relationships at age 9. PMID:28401848
Attachment security mediates the longitudinal association between child-parent psychotherapy and peer relations for toddlers of depressed mothers.

PubMed

Guild, Danielle J; Toth, Sheree L; Handley, Elizabeth D; Rogosch, Fred A; Cicchetti, Dante

2017-05-01

Numerous investigations have demonstrated that child-parent psychotherapy (CPP) promotes secure attachment between mothers and offspring. However, the role of postintervention attachment security as it relates to long-term child outcomes has never been evaluated. The present study therefore examined postintervention attachment status as a mediator of the association between CPP for depressed mothers and their offspring and subsequent peer relations among offspring. Depressed mothers and their toddlers were randomized to receive CPP (n = 45) or to a control group (n = 55). A prior investigation with this sample indicated that offspring who received CPP attained significantly higher rates of secure attachment postintervention, whereas insecure attachment continued to predominate for offspring in the control group. The present study examined follow-up data of teachers' reports on participants' competence with classroom peers when they were approximately 9 years old. Findings indicated that children who received CPP were more likely to evidence secure attachments at postintervention, which in turn was associated with more positive peer relationships at age 9.

Parental mentalizing as an indirect link between attachment anxiety and parenting satisfaction.

PubMed

Burkhart, Margaret L; Borelli, Jessica L; Rasmussen, Hannah F; Brody, Robin; Sbarra, David A

2017-03-01

Attachment anxiety in parents is associated with lower quality parent-child relationships. An inhibited capacity to reflect on children's mental states, referred to as prementalizing, may reduce the pleasure parents derive from their relationships. In the current study, we explored the associations among attachment anxiety, prementalizing, and parenting satisfaction in two groups of participants randomly assigned either to reflect on a positive memory with their child (n = 150) or to reflect on a positive memory not involving their child (n = 150). Narratives were evaluated for positive content using two metrics: coder-rated positivity and frequency of positive emotion words. Results revealed that self-reported prementalizing operated indirectly to link attachment anxiety and self-reported parenting satisfaction for both groups. However, prementalizing only served as an indirect link between attachment anxiety and coded measures of positivity among participants who reflected on parenting experiences, suggesting the specificity of prementalizing in linking attachment anxiety and reduced positivity in the parenting role. The results have implications for understanding influences of attachment and mentalization on parents' perception of parent-child relationship quality. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Determinants of Child Attachment in the Years Postpartum in a High-Risk Sample of Immigrant Women.

PubMed

Lecompte, Vanessa; Rousseau, Cécile

2017-10-07

Our goal was to examine maternal mental health and associated stresses in a sample of high-risk immigrant mothers, and its association with child insecure attachment in the years following childbirth. Mothers and their child (Mage = 37 months) were recruited through a Health and Social Service organization in the Parc-Extension neighborhood in Montreal, Quebec. Mothers completed the Hopkins Symptoms Checklist (HSCL-25), the Multidimensional Scale of Perceived Social Support (MPSS) and a sociodemographic questionnaire that included questions on premature delivery and birth weight. Attachment behaviors were coded out of a videotaped free play sequence using the Preschool and Early School-Age Attachment Rating Scales (PARS). Analysis revealed high levels of clinical anxiety and depression, low social support and low attachment security. Significant mean differences and associations were found between anxiety, depression, social support, preterm delivery and child attachment. These results underscore the importance of screening for anxiety and depression early in the postnatal years, in order to prevent associated consequences such as child insecure attachment. Results also highlight the importance of building positive social networks, especially with immigrant populations.
Attachment Orientations, Respiratory Sinus Arrhythmia, and Stress Are Important for Understanding the Link Between Childhood Socioeconomic Status and Adult Self-Reported Health.

PubMed

Murdock, Kyle W; Fagundes, Christopher P

2017-04-01

Low childhood socioeconomic status (SES) is reliably associated with poor adult health. Social environments early in life and physiological stress responses are theorized to underlie this link; however, the role of attachment orientations is relatively unknown. In this study, we examined whether attachment orientations (i.e., attachment anxiety and attachment avoidance) and self-reported stress were mediators of the association between childhood SES and self-reported health in adulthood. Furthermore, we examined whether parasympathetic nervous system functioning was a moderator of associations between attachment orientations and self-reported stress. Participants (N = 213) provided self-reports of childhood SES, attachment orientations, general stress, and self-rated health. Respiratory sinus arrhythmia (RSA) was measured at rest, as well as during an acute social stressor. Low childhood SES was associated with poor self-reported health via the serial pathway from attachment anxiety to general stress. Moreover, attachment avoidance was associated with self-reported health via general stress, but only among those with high stress-induced RSA. Findings were independent of participant age, sex, race, body mass index, baseline RSA, and adult SES. Attachment theory is useful for understanding why those from low SES backgrounds are at greater risk of negative health outcomes in adulthood. Findings extend our knowledge of how interpersonal relationships in childhood can shape emotional and physical health outcomes in adulthood.
Attachment Orientations, Respiratory Sinus Arrhythmia, and Stress are Important for Understanding the Link between Childhood Socioeconomic Status and Adult Self-Reported Health

PubMed Central

Murdock, Kyle W.; Fagundes, Christopher P.

2016-01-01

Background Low childhood SES is reliably associated with poor adult health. Social environments early in life and physiological stress responses are theorized to underlie this link; however, the role of attachment orientations is relatively unknown. Purpose In this study, we examined whether attachment orientations (i.e., attachment anxiety and attachment avoidance) and self-reported stress were mediators of the association between childhood SES and self-reported health in adulthood. Furthermore, we examined whether parasympathetic nervous system functioning was a moderator of associations between attachment orientations and self-reported stress. Methods Participants (N = 213) provided self-reports of childhood SES, attachment orientations, stress, and self-rated health. Respiratory sinus arrhythmia (RSA) was measured at rest, as well as during an acute social stressor. Results Low childhood SES was associated with poor self-reported health via the serial pathway from attachment anxiety to general stress. Moreover, attachment avoidance was associated with self-reported health via general stress, but only among those with high stress-induced RSA. Findings were independent of participant age, sex, race, body mass index, baseline RSA, and adult SES. Conclusions Attachment theory is useful for understanding why those from low SES backgrounds are at greater risk of negative health outcomes in adulthood. Findings extend our knowledge of how interpersonal relationships in childhood can shape emotional and physical health outcomes in adulthood. PMID:27679464
Modeling of Impression Testing to Obtain Mechanical Properties of Lead-Free Solders Microelectronic Interconnects

DTIC Science & Technology

2005-12-01

hardening exponent and Cimp is the impression strain-rate hardening coefficient. The strain-rate hardening exponent m is a parameter that is...exponent and Cimp is the impression strain-rate hardening coefficient. The strain-rate hardening exponent m is a parameter that is related to the creep
Determination of Time Dependent Virus Inactivation Rates

NASA Astrophysics Data System (ADS)

Chrysikopoulos, C. V.; Vogler, E. T.

2003-12-01

A methodology is developed for estimating temporally variable virus inactivation rate coefficients from experimental virus inactivation data. The methodology consists of a technique for slope estimation of normalized virus inactivation data in conjunction with a resampling parameter estimation procedure. The slope estimation technique is based on a relatively flexible geostatistical method known as universal kriging. Drift coefficients are obtained by nonlinear fitting of bootstrap samples and the corresponding confidence intervals are obtained by bootstrap percentiles. The proposed methodology yields more accurate time dependent virus inactivation rate coefficients than those estimated by fitting virus inactivation data to a first-order inactivation model. The methodology is successfully applied to a set of poliovirus batch inactivation data. Furthermore, the importance of accurate inactivation rate coefficient determination on virus transport in water saturated porous media is demonstrated with model simulations.
Sensory Processing Relates to Attachment to Childhood Comfort Objects of College Students

ERIC Educational Resources Information Center

Kalpidou, Maria

2012-01-01

The author tested the hypothesis that attachment to comfort objects is based on the sensory processing characteristics of the individual. Fifty-two undergraduate students with and without a childhood comfort object reported sensory responses and performed a tactile threshold task. Those with a comfort object described their object and rated their…
Associations between First-Time Expectant Women's Representations of Attachment and Their Physiological Reactivity to Infant Cry

ERIC Educational Resources Information Center

Ablow, Jennifer C.; Marks, Amy K.; Shirley Feldman, S.; Huffman, Lynne C.

2013-01-01

Associations among 53 primiparous women's Adult Attachment Interview classifications (secure-autonomous vs. insecure-dismissing) and physiological and self-reported responses to infant crying were explored. Heart rate, skin conductance levels, and respiratory sinus arrhythmia (RSA) were recorded continuously. In response to the cry,…
Parabolic trough solar collector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eaton, J.H.

1985-01-15

A parabolic trough solar collector using reflective flexible materials is disclosed. A parabolic cylinder mirror is formed by stretching a flexible reflecting material between two parabolic end formers. The formers are held in place by a spreader bar. The resulting mirror is made to track the sun, focusing the sun's rays on a receiver tube. The ends of the reflective material are attached by glue or other suitable means to attachment straps. The flexible mirror is then attached to the formers. The attachment straps are mounted in brackets and tensioned by tightening associated nuts on the ends of the attachmentmore » straps. This serves both to stretch the flexible material orthogonal to the receiver tube and to hold the flexible material on the formers. The flexible mirror is stretched in the direction of the receiver tube by adjusting tensioning nuts. If materials with matching coefficients of expansion for temperature and humidity have been chosen, for example, aluminum foil for the flexible mirror and aluminum for the spreader bar, the mirror will stay in adjustment through temperature and humidity excursions. With dissimilar materials, e.g., aluminized mylar or other polymeric material and steel, spacers can be replaced with springs to maintain proper adjustment. The spreader bar cross section is chosen to be in the optic shadow of the receiver tube when tracking and not to intercept rays of the sun that would otherwise reach the receiver tube. This invention can also be used to make non-parabolic mirrors for other apparatus and applications.« less
Functionally Different Pads on the Same Foot Allow Control of Attachment: Stick Insects Have Load-Sensitive “Heel” Pads for Friction and Shear-Sensitive “Toe” Pads for Adhesion

PubMed Central

Labonte, David; Federle, Walter

2013-01-01

Stick insects (Carausius morosus) have two distinct types of attachment pad per leg, tarsal “heel” pads (euplantulae) and a pre-tarsal “toe” pad (arolium). Here we show that these two pad types are specialised for fundamentally different functions. When standing upright, stick insects rested on their proximal euplantulae, while arolia were the only pads in surface contact when hanging upside down. Single-pad force measurements showed that the adhesion of euplantulae was extremely small, but friction forces strongly increased with normal load and coefficients of friction were 1. The pre-tarsal arolium, in contrast, generated adhesion that strongly increased with pulling forces, allowing adhesion to be activated and deactivated by shear forces, which can be produced actively, or passively as a result of the insects' sprawled posture. The shear-sensitivity of the arolium was present even when corrected for contact area, and was independent of normal preloads covering nearly an order of magnitude. Attachment of both heel and toe pads is thus activated partly by the forces that arise passively in the situations in which they are used by the insects, ensuring safe attachment. Our results suggest that stick insect euplantulae are specialised “friction pads” that produce traction when pressed against the substrate, while arolia are “true” adhesive pads that stick to the substrate when activated by pulling forces. PMID:24349156
Design of h-Darrieus vertical axis wind turbine

NASA Astrophysics Data System (ADS)

Parra, Teresa; Vega, Carmen; Gallegos, A.; Uzarraga, N. C.; Castro, F.

2015-05-01

Numerical simulation is used to predict the performance of a Vertical Axis Wind Turbine (VAWT) H-Darrieus. The rotor consists of three straight blades with shape of aerofoil of the NACA family attached to a rotating vertical shaft. The influence of the solidity is tested to get design tendencies. The mesh has two fluid volumes: one sliding mesh for the rotor where the rotation velocity is established while the other is the environment of the rotor. Bearing in mind the overall flow is characterized by important secondary flows, the turbulence model selected was realizable k-epsilon with non-equilibrium wall functions. Conservation equations were solved with a Third-Order Muscl scheme using SIMPLE to couple pressure and velocity. During VAWT operation, the performance depends mainly on the relative motion of the rotating blade and has a fundamental period which depends both on the rate of rotation and the number of blades. The transient study is necessary to characterise the hysteresis phenomenon. Hence, more than six revolutions get the periodic behaviour. Instantaneous flows provide insight about wake structure interaction. Time averaged parameters let obtain the characteristic curves of power coefficient.
A Model for Negative Ion Chemistry in Titan’s Ionosphere

NASA Astrophysics Data System (ADS)

Mukundan, Vrinda; Bhardwaj, Anil

2018-04-01

We developed a one-dimensional photochemical model for the dayside ionosphere of Titan for calculating the density profiles of negative ions under steady-state photochemical equilibrium condition. We concentrated on the T40 flyby of the Cassini orbiter and used the in situ measurements from instruments on board Cassini as input to the model. Using the latest available reaction rate coefficients and dissociative electron attachment cross sections, the densities of 10 anions are calculated. Our study shows CN‑ as the dominant anion, followed by C3N‑, which agrees with the results of previous calculations. We suggest that H‑ could be an important anion in Titan’s ionosphere and is the second most abundant anion at altitudes greater than 1200 km. The main production channel of the major ion CN‑ is the reaction of H‑ with HCN. The H‑ also play a major role in the production of anions C2H‑, C6H‑, and OH‑. We present a comparison of the calculated ion density profiles with the relative density profiles derived using recently reported Cassini CAPS/ELS observations.
A far-red fluorescent protein evolved from a cyanobacterial phycobiliprotein.

PubMed

Rodriguez, Erik A; Tran, Geraldine N; Gross, Larry A; Crisp, Jessica L; Shu, Xiaokun; Lin, John Y; Tsien, Roger Y

2016-09-01

Far-red fluorescent proteins (FPs) are desirable for in vivo imaging because with these molecules less light is scattered, absorbed, or re-emitted by endogenous biomolecules compared with cyan, green, yellow, and orange FPs. We developed a new class of FP from an allophycocyanin α-subunit (APCα). Native APC requires a lyase to incorporate phycocyanobilin. The evolved FP, which we named small ultra-red FP (smURFP), covalently attaches a biliverdin (BV) chromophore without a lyase, and has 642/670-nm excitation-emission peaks, a large extinction coefficient (180,000 M(-1)cm(-1)) and quantum yield (18%), and photostability comparable to that of eGFP. smURFP has significantly greater BV incorporation rate and protein stability than the bacteriophytochrome (BPH) FPs. Moreover, BV supply is limited by membrane permeability, and smURFPs (but not BPH FPs) can incorporate a more membrane-permeant BV analog, making smURFP fluorescence comparable to that of FPs from jellyfish or coral. A far-red and near-infrared fluorescent cell cycle indicator was created with smURFP and a BPH FP.
Photothermal therapy of Lewis lung carcinoma in mice using gold nanoshells on carboxylated polystyrene spheres

NASA Astrophysics Data System (ADS)

Liu, Huiyu; Chen, Dong; Tang, Fangqiong; Du, Gangjun; Li, Linlin; Meng, Xianwei; Liang, Wei; Zhang, Yangde; Teng, Xu; Li, Yi

2008-11-01

A new approach towards the design of gold nanoshells on carboxylated polystyrene spheres (GNCPSs) is reported here. Gold nanoshells were self-assembled on the surface of carboxylated polystyrene spheres by a seed growth method. Chitosan (CHI) was used as a functional agent of carboxylated polystyrene spheres for attaching gold seeds. The surface plasmon resonance (SPR) peak of GNCPSs can be tuned, greatly redshifted, over a broad spectral range including the near-infrared (NIR) wavelength region, which provides maximal penetration of light through tissue. Irradiation of GNCPSs at their peak extinction coefficient results in the conversion of light to heat energy that produces a local rise in temperature. Our study revealed that the Lewis lung carcinoma (LLC) in mice treated with GNCPSs exposed to a low dose of NIR light (808 nm, 4 W cm-2) induced irreversible tissue damage. The tumor volumes of the treatment group by GNCPSs were significantly lower than those of control groups, with an average inhibition rate over 55% (P<0.005). This study proves that GNCPSs are promising in plasmonic photothermal tumor therapy.
The influence of negative ions in helium-oxygen barrier discharges: III. Simulation of laser photodetachment and comparison with experiment

NASA Astrophysics Data System (ADS)

Nemschokmichal, Sebastian; Tschiersch, Robert; Meichsner, Jürgen

2017-11-01

The laser photodetachment experiment in a diffuse helium-oxygen barrier discharge is evaluated by a 1D fluid simulation. As in the experiment, the simulated discharge operates in helium with 400 {ppm} oxygen admixture at 500 {mbar} inside a discharge gap of 3 {mm}. The laser photodetachment is included by the interaction of negative ions with a temporally and spatially dependent photon flux. The simulation with the usually applied set of reactions and rate coefficients provides a much lower negative ion density than needed to explain the impact on the discharge characteristics in the experiment. Further processes for an enhanced negative ion formation and their capabilities of reproducing the experimental results are discussed. These further processes are additional attachment processes in the volume and the negative ion formation at the negatively charged dielectric. Both approaches are able to reproduce the measured laser photodetachment effect partially, but the best agreement with the experimental results is achieved with the formation of negative ions at the negatively charged dielectric.
[Comparison of attachment-related social behaviors in autistic disorder and developmental disability].

PubMed

Akdemir, Devrim; Pehlivantürk, Berna; Unal, Fatih; Ozusta, Seniz

2009-01-01

This study examined social behaviors related to attachment in children with autistic disorder and the differences in these behaviors from those observed in developmentally disabled children. Additionally, we aimed to investigate the relationship between attachment behaviors and clinical variables, such as age, cognitive development, severity of autism, language development, and mothers' attachment styles. The study group consisted of 19 children with autistic disorder (mean age: 37.9 +/- 6.8 months) and the control group consisted of 18 developmentally disabled children without autistic disorder that were matched with respect to age, gender, and cognitive development. The Childhood Autism Rating Scale (CARS) was administered to all the children by two child psychiatrists. Mothers completed the Relationships Scale Questionnaire (RSQ). Cognitive development of the children was assessed with the Stanford-Binet intelligence scale. Attachment behaviors of the children were evaluated with a modified Strange Situation Procedure (SSP). Attachment behaviors in the children with autistic disorder and in the children with developmental disabilities were similar. In contrast to the developmentally disabled group, the children with autistic disorder stayed closer toward their mothers compared with their responses to strangers. In the autistic disorder group, attachment behaviors were not associated with age, intelligence quotient, or mothers' attachment styles; however, a significant relationship between the severity of autism and the presence of speech was observed. Parents' understanding of the attachment needs and the attachment behaviors of their autistic children in the early stages of the disorder may lead to more secure attachment relationships and improved social development.
Interaction of Chlamydia trachomatis organisms and HeLa 229 cells.

PubMed Central

Kuo, C C; Grayston, T

1976-01-01

The infection of HeLa 229 cells in monolayer culture with trachoma (B/TW-5/OT) and lymphogranuloma venereum (LGV) (L2/434/Bu) organism was studied in terms of two parameters: radioactivity counts of cell-associated tritium labeled organisms at the initial stage of inoculation for measurement of attachment, and inclusion counts of infection cells after incubation for measurement of growth. Factors affecting attachment and inclusion formation and correlation of the two are presented. It was shown that attachment is an important initial step in infection by Chlamydia trachomatis. The rate of attachment was temperature dependent. The attachment of LGV organisms was affected more profoundly by temperature than was that of trachoma organisms. Attachment and inclusion formation of trachoma and LGV organisms were inhibited by heparin. Diethylaminoethyl-dextran was again shown to enhance attachment and inclusion formation of trachoma but not LGV organisms. NaF had no effect on attachment, but inhibited inclusion formation of both trachoma and LGV organisms. Both attachment and inclusion formation of trachoma organisms were strongly enhanced by centrifugation of the inoculum onto the cell monolayer. Although inclusion formation of trachoma organism was much greater in susceptible cells (HeLa 229) than relatively insusceptible cells (fetal tonsil), attachment was only slightly greater. The results based on the test of two cell lines suggested that attachment prpbably is not a critical factor in determing a cell line's susceptibility to infection with trachoma organisms. PMID:179950
The effect of an extraluminal transducer on the reproductive capability of the rabbit.

PubMed

Fromm, E; Garcia, C R; Jeutter, D C; Anid, A; Epstein, S

1976-12-01

An extraluminally attached microminiature force transducer, designed for reproductive tract contractility measurements, was investigated in terms of its effects on the physiology of the uterotubal junction in the rabbit. The presence or attachment process of the extraluminal force transducer (EFT) did not affect the rate of pregnancy or the number of embryonic implantation sites whether the attached device was silicone rubber or polyethylene-encased. The uterotubal junction was able to retain the blastocyst for the required time after mating, while an examination of postembryonic mortality revealed a rate of one resorption in some experimental groups. The gestation period was unaffected by the EFT, ranging from 30 to 40 days with a mode of 32, while histologic examinations revealed formation of a thin fibroblastic layer, some increased vascularity, and no abnormal leukocytic accumulation.
Technical characterization of dialysis fluid flow and mass transfer rate in dialyzers with various filtration coefficients using dimensionless correlation equation.

PubMed

Fukuda, Makoto; Yoshimura, Kengo; Namekawa, Koki; Sakai, Kiyotaka

2017-06-01

The objective of the present study is to evaluate the effect of filtration coefficient and internal filtration on dialysis fluid flow and mass transfer coefficient in dialyzers using dimensionless mass transfer correlation equations. Aqueous solution of vitamin B 12 clearances were obtained for REXEED-15L as a low flux dialyzer, and APS-15EA and APS-15UA as high flux dialyzers. All the other design specifications were identical for these dialyzers except for filtration coefficient. The overall mass transfer coefficient was calculated, moreover, the exponents of Reynolds number (Re) and film mass transfer coefficient of the dialysis-side fluid (k D ) for each flow rate were derived from the Wilson plot and dimensionless correlation equation. The exponents of Re were 0.4 for the low flux dialyzer whereas 0.5 for the high flux dialyzers. Dialysis fluid of the low flux dialyzer was close to laminar flow because of its low filtration coefficient. On the other hand, dialysis fluid of the high flux dialyzers was assumed to be orthogonal flow. Higher filtration coefficient was associated with higher k D influenced by mass transfer rate through diffusion and internal filtration. Higher filtration coefficient of dialyzers and internal filtration affect orthogonal flow of dialysis fluid.
Calculation of equivalent friction coefficient for castor seed by single screw press

NASA Astrophysics Data System (ADS)

Liu, R.; Xiao, Z.; Li, C.; Zhang, L.; Li, P.; Li, H.; Zhang, A.; Tang, S.; Sun, F.

2017-08-01

Based on the traction angle and transportation rate equation, castor beans were pressed by application of single screw under different cake diameter and different screw speed. The results showed that the greater the cake diameter and screw rotation speed, the greater the actual transmission rate was. The equivalent friction coefficient was defined and calculated as 0.4136, and the friction coefficients between press material and screw, bar cage were less than the equivalent friction coefficient value.

Intergenerational transmission of attachment for infants raised in a prison nursery.

PubMed

Byrne, M W; Goshin, L S; Joestl, S S

2010-07-01

Within a larger intervention study, attachment was assessed with the Strange Situation Procedure for 30 infants who co-resided with their mothers in a prison nursery. Sixty percent of infants were classified secure, 75% who co-resided a year or more and 43% who co-resided less than a year, all within the range of normative community samples. The year-long co-residing group had significantly more secure and fewer disorganized infants than predicted by their mothers' attachment status, measured by the Adult Attachment Interview, and a significantly greater proportion of secure infants than meta-analyzed community samples of mothers with low income, depression, or drug/alcohol abuse. Using intergenerational data collected with rigorous methods, this study provides the first evidence that mothers in a prison nursery setting can raise infants who are securely attached to them at rates comparable to healthy community children, even when the mother's own internal attachment representation has been categorized as insecure.
Intergenerational Transmission of Attachment for Infants Raised in a Prison Nursery

PubMed Central

Byrne, M. W.; Goshin, L. S.; Joestl, S. S.

2010-01-01

Within a larger intervention study, attachment was assessed with the Strange Situation Procedure for 30 infants who co-resided with their mothers in a prison nursery. Sixty percent of infants were classified secure, 75% who co-resided a year or more and 43% who co-resided less than a year, all within the range of normative community samples. The year-long co-residing group had significantly more secure and fewer disorganized infants than predicted by their mothers’ attachment status, measured by the Adult Attachment Interview, and a significantly greater proportion of secure infants than meta-analyzed community samples of mothers with low income, depression, or drug/alcohol abuse. Using intergenerational data collected with rigorous methods, this study provides the first evidence that mothers in a prison nursery setting can raise infants who are securely attached to them at rates comparable to healthy community children, even when the mother’s own internal attachment representation has been categorized as insecure. PMID:20582846
Attachment style, relationship quality, and psychological distress in patients with psychogenic non-epileptic seizures versus epilepsy.

PubMed

Green, Becky; Norman, Paul; Reuber, Markus

2017-01-01

Psychopathology levels are elevated in patients with psychogenic non-epileptic seizures (PNES) and those with epilepsy. However, patients with PNES report higher rates of trauma and neglect, poorer health-related quality of life (HRQoL), and an increased prevalence of insecure attachment. We examined to what extent attachment style and relationship quality with their main informal carer impact on levels of HRQoL, depression, and anxiety in patients with PNES versus those with epilepsy. Consecutive patients with PNES (N=23) and epilepsy (N=72) completed questionnaires about attachment style, quality of their relationship with their main informal carer, seizure severity, HRQoL, depression, and anxiety. Patients with PNES reported higher levels of anxiety and depression and lower HRQoL than those with epilepsy. PNES: No significant correlations were found with HRQoL but depression correlated positively with attachment avoidance, attachment anxiety, and relationship conflict. Anxiety correlated positively with attachment avoidance, attachment anxiety, and relationship conflict, and negatively with relationship depth and support. Epilepsy: HRQoL correlated negatively with seizure severity, depression, anxiety, attachment avoidance, and attachment anxiety. Depression correlated positively with attachment avoidance, attachment anxiety, and relationship conflict. Anxiety correlated positively with seizure severity, attachment avoidance, and attachment anxiety. Correlations between measures of relationship quality and anxiety were stronger in patients with PNES versus those with epilepsy (zs=2.66 to 2.97, ps<0.004). Attachment style and relationship quality explained larger amounts of variance in depression (45%) and anxiety (60%) in the patients with PNES than those with epilepsy (16% and 13%). Levels of anxiety and depression were higher in patients with PNES than those with epilepsy. Interpersonal problems were much more closely associated with anxiety and depression in patients with PNES than those with epilepsy. The findings support the use of therapeutic interventions for PNES focusing on attachment and relationship issues. Copyright © 2016 Elsevier Inc. All rights reserved.
Micropollutant removal by attached and suspended growth in a hybrid biofilm-activated sludge process.

PubMed

Falås, P; Longrée, P; la Cour Jansen, J; Siegrist, H; Hollender, J; Joss, A

2013-09-01

Removal of organic micropollutants in a hybrid biofilm-activated sludge process was investigated through batch experiments, modeling, and full-scale measurements. Batch experiments with carriers and activated sludge from the same full-scale reactor were performed to assess the micropollutant removal rates of the carrier biofilm under oxic conditions and the sludge under oxic and anoxic conditions. Clear differences in the micropollutant removal kinetics of the attached and suspended growth were demonstrated, often with considerably higher removal rates for the biofilm compared to the sludge. For several micropollutants, the removal rates were also affected by the redox conditions, i.e. oxic and anoxic. Removal rates obtained from the batch experiments were used to model the micropollutant removal in the full-scale process. The results from the model and plant measurements showed that the removal efficiency of the process can be predicted with acceptable accuracy (± 25%) for most of the modeled micropollutants. Furthermore, the model estimations indicate that the attached growth in hybrid biofilm-activated sludge processes can contribute significantly to the removal of individual compounds, such as diclofenac. Copyright © 2013 Elsevier Ltd. All rights reserved.
Simulation and experiment of thermal fatigue in the CPV die attach

NASA Astrophysics Data System (ADS)

Bosco, Nick; Silverman, Timothy; Kurtz, Sarah

2012-10-01

FEM simulation and accelerated thermal cycling have been performed for the CPV die attach. Trends in fatigue damage accumulation and equivalent test time are explored and found to be most sensitive to temperature ramp rate. Die attach crack growth is measured through cycling and found to be in excellent agreement with simulations of the inelastic strain energy accumulated. Simulations of an entire year of weather data provides for the relative ranking of fatigue damage between four cities as well as their equivalent accelerated test time.
From Peptides to Proteins: Systematic Control of Net Molecular Charge and Hydrophilicity on the Kinetics of Calcite Growth

NASA Astrophysics Data System (ADS)

Elhadj, S.; de Yoreo, J. J.; Hoyer, J. J.; Dove, P. M.

2006-12-01

The compartment-specific compositions of biologic molecules isolated from biominerals suggest that control of mineral growth may be linked to biochemical features. Here we define a systematic relationship between the ability of biomolecules in solution to promote the growth of calcite (CaCO3) and their net negative molecular charge and hydrophilicity. The degree of enhancement is dependent on peptide composition, but not on peptide sequence. Data analysis shows that this rate enhancement arises from an increase in the kinetic coefficient. We interpret the mechanism of growth enhancement to be a catalytic process whereby biomolecules reduce the magnitude of the diffusive barrier, Ek, by perturbations that displace water molecules- a water shell destruction mechanism. The result is a decrease in the repulsive barrier for attachment of solutes to the solid phase. This previously unrecognized relationship also rationalizes recently reported data showing acceleration of calcite growth rates over rates measured in the pure system by nanomolar levels of abalone nacre proteins. These findings show that the growth-modifying properties of small model peptides may be scaled up to analyze mineralization processes that are mediated by more complex proteins. We suggest that enhancement of calcite growth may now be estimated a priori from the composition of peptide sequences and the calculated values of hydrophilicity and net molecular charge without need for detailed tests for each biomolecule. This insight may contribute to an improved understanding of mineralization in diverse systems of biomineralization.
Ceramic blade attachment system

DOEpatents

Shaffer, J.E.

1995-07-11

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figs.
Ceramic blade attachment system

DOEpatents

Shaffer, James E.

1995-01-01

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.
A self-consistent, multivariate method for the determination of gas-phase rate coefficients, applied to reactions of atmospheric VOCs and the hydroxyl radical

NASA Astrophysics Data System (ADS)

Shaw, Jacob T.; Lidster, Richard T.; Cryer, Danny R.; Ramirez, Noelia; Whiting, Fiona C.; Boustead, Graham A.; Whalley, Lisa K.; Ingham, Trevor; Rickard, Andrew R.; Dunmore, Rachel E.; Heard, Dwayne E.; Lewis, Ally C.; Carpenter, Lucy J.; Hamilton, Jacqui F.; Dillon, Terry J.

2018-03-01

Gas-phase rate coefficients are fundamental to understanding atmospheric chemistry, yet experimental data are not available for the oxidation reactions of many of the thousands of volatile organic compounds (VOCs) observed in the troposphere. Here, a new experimental method is reported for the simultaneous study of reactions between multiple different VOCs and OH, the most important daytime atmospheric radical oxidant. This technique is based upon established relative rate concepts but has the advantage of a much higher throughput of target VOCs. By evaluating multiple VOCs in each experiment, and through measurement of the depletion in each VOC after reaction with OH, the OH + VOC reaction rate coefficients can be derived. Results from experiments conducted under controlled laboratory conditions were in good agreement with the available literature for the reaction of 19 VOCs, prepared in synthetic gas mixtures, with OH. This approach was used to determine a rate coefficient for the reaction of OH with 2,3-dimethylpent-1-ene for the first time; k = 5.7 (±0.3) × 10-11 cm3 molecule-1 s-1. In addition, a further seven VOCs had only two, or fewer, individual OH rate coefficient measurements available in the literature. The results from this work were in good agreement with those measurements. A similar dataset, at an elevated temperature of 323 (±10) K, was used to determine new OH rate coefficients for 12 aromatic, 5 alkane, 5 alkene and 3 monoterpene VOC + OH reactions. In OH relative reactivity experiments that used ambient air at the University of York, a large number of different VOCs were observed, of which 23 were positively identified. Due to difficulties with detection limits and fully resolving peaks, only 19 OH rate coefficients were derived from these ambient air samples, including 10 reactions for which data were previously unavailable at the elevated reaction temperature of T = 323 (±10) K.
2D and 3D impellers of centrifugal compressors - advantages, shortcomings and fields of application

NASA Astrophysics Data System (ADS)

Galerkin, Y.; Reksrin, A.; Drozdov, A.

2017-08-01

The simplified equations are presented for calculation of inlet dimensions and velocity values for impellers with three-dimensional blades located in axial and radial part of an impeller (3D impeller) and with two-dimensional blades in radial part (2D). Considerations concerning loss coefficients of 3D and 2D impellers at different design flow rate coefficients are given. The tendency of reduction of potential advantages of 3D impellers at medium and small design flow rate coefficients is shown. The data on high-efficiency compressors and stages with 2D impellers coefficients designed by the authors are presented. The reached efficiency level of 88 - 90% makes further increase of efficiency by the application of 3D impellers doubtful. CFD-analysis of stage candidates with medium flow rate coefficient with 3D and 2D impellers revealed specific problems. In some cases the constructive advantage of a 2D impeller is smaller hub ratio. It makes possible the reaching of higher efficiency. From other side, there is a positive tendency of gas turbine drive RPM increase. 3D impellers have no alternative for stages with high flow rate coefficients matching high-speed drive.
Quantification and classification of neuronal responses in kernel-smoothed peristimulus time histograms

PubMed Central

Fried, Itzhak; Koch, Christof

2014-01-01

Peristimulus time histograms are a widespread form of visualizing neuronal responses. Kernel convolution methods transform these histograms into a smooth, continuous probability density function. This provides an improved estimate of a neuron's actual response envelope. We here develop a classifier, called the h-coefficient, to determine whether time-locked fluctuations in the firing rate of a neuron should be classified as a response or as random noise. Unlike previous approaches, the h-coefficient takes advantage of the more precise response envelope estimation provided by the kernel convolution method. The h-coefficient quantizes the smoothed response envelope and calculates the probability of a response of a given shape to occur by chance. We tested the efficacy of the h-coefficient in a large data set of Monte Carlo simulated smoothed peristimulus time histograms with varying response amplitudes, response durations, trial numbers, and baseline firing rates. Across all these conditions, the h-coefficient significantly outperformed more classical classifiers, with a mean false alarm rate of 0.004 and a mean hit rate of 0.494. We also tested the h-coefficient's performance in a set of neuronal responses recorded in humans. The algorithm behind the h-coefficient provides various opportunities for further adaptation and the flexibility to target specific parameters in a given data set. Our findings confirm that the h-coefficient can provide a conservative and powerful tool for the analysis of peristimulus time histograms with great potential for future development. PMID:25475352
Radon progeny size distributions and enhanced deposition effects from high radon concentrations in an enclosed chamber.

PubMed

Leonard, Bobby E

2004-01-01

Prior work studying radon progeny in a small enclosed chamber found that at high (222)Rn concentrations an enhanced surface deposition was observed. Subsequent measurements for unfiltered air showed minimal charged particle mobility influence. Progeny particle size measurements reported here, performed at the US Department of Energy Environmental Measurement Laboratory (now with Home Security Department), using the EML graded screen array (GSA) system show in unfiltered air that the high (222)Rn levels causes a reduction in the attached (218)Po progeny airborne particulates and formation of additional normal sized unattached ( approximately 0.80 nm) and also even smaller (218)Po below 0.50 nm. At a (222)Rn level of 51 kBq m(-3), 73% of all (218)Po are of a mean particle diameter of about 0.40 +/- 0.02 nm. At this (222)Rn level, the ratio of (218)Po to (222)Rn airborne concentrations is reduced significantly from the concentration ratio at low (222)Rn levels. Similar reductions and size reformations were observed for the (214)Pb and (214)Bi/Po progeny. The particle size changes are further confirmed using the plateout rates and corresponding deposition velocities. The Crump and Seinfeld deposition theory provides the corresponding particle diffusion coefficients. With the diffusion coefficient to ultrafine clustered particle diameter correlation of Ramamurthi and Hopke, good agreement is obtained between EML GSA and deposition velocity data down to 0.40 nm. Strong evidence is presented that the progeny size reduction is due to, as a result of air ionization, the increased neutralization rate (primarily from electron scavenging of OH molecules) of the initially charged progeny. This is shown to increase with the (1/2) power of (222)Rn concentration and relative humidity as well as increased air change rate in the chamber. These results imply that at (222)Rn levels above 50 kBq m(-3), at relative humidity of 52%, a considerable reduction in lung dose could occur from preferential deposition of the progeny in the nasal and oral passages.
Development of a fully integrated falling film microreactor for gas-liquid-solid biotransformation with surface immobilized O2 -dependent enzyme.

PubMed

Bolivar, Juan M; Krämer, Christina E M; Ungerböck, Birgit; Mayr, Torsten; Nidetzky, Bernd

2016-09-01

Microstructured flow reactors are powerful tools for the development of multiphase biocatalytic transformations. To expand their current application also to O2 -dependent enzymatic conversions, we have implemented a fully integrated falling film microreactor that provides controllable countercurrent gas-liquid phase contacting in a multi-channel microstructured reaction plate. Advanced non-invasive optical sensing is applied to measure liquid-phase oxygen concentrations in both in- and out-flow as well as directly in the microchannels (width: 600 μm; depth: 200 μm). Protein-surface interactions are designed for direct immobilization of catalyst on microchannel walls. Target enzyme (here: d-amino acid oxidase) is fused to the positively charged mini-protein Zbasic2 and the channel surface contains a negatively charged γ-Al2 O3 wash-coat layer. Non-covalent wall attachment of the chimeric Zbasic2 _oxidase resulted in fully reversible enzyme immobilization with fairly uniform surface coverage and near complete retention of biological activity. The falling film at different gas and liquid flow rates as well as reactor inclination angles was shown to be mostly wavy laminar. The calculated film thickness was in the range 0.5-1.3 × 10(-4) m. Direct O2 concentration measurements at the channel surface demonstrated that the liquid side mass transfer coefficient (KL ) for O2 governed the overall gas/liquid/solid mass transfer and that the O2 transfer rate (≥0.75 mM · s(-1) ) vastly exceeded the maximum enzymatic reaction rate in a wide range of conditions. A value of 7.5 (±0.5) s(-1) was determined for the overall mass transfer coefficient KL a, comprising a KL of about 7 × 10(-5) m · s(-1) and a specific surface area of up to 10(5) m(-1) . Biotechnol. Bioeng. 2016;113: 1862-1872. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Energetics of the Ventilatory Piston Pump of the Lugworm, a Deposit-feeding Polychaete Living in a Burrow.

PubMed

Toulmond, A; Dejours, P

1994-04-01

The aim of this study was to tentatively estimate the energy cost of breathing in the lugworm, Arenicola marina (L.), a gallery-dwelling, piston-pump breather that moves water in a tail-to-head direction. Each tested lugworm was placed in a horizontal glass tube. The caudal end of the tube was connected to a well-aerated seawater reservoir at 20{deg}C, and the cephalic end attached to a drop meter through a tube resistance. At the exit of the cephalic chamber the O2 tension was recorded via an in situ O2 electrode, and the hydrostatic pressure of the exhaled water was also recorded. Water flow rate, total O2 uptake rate {Mdot}TOTO2, O2 extraction coefficient, and the mechanical power necessary to pump water through the resistive anterior exit of the apparatus ({Wdot}MEC), were computed. The basal metabolic rate of each animal ({Mdot}CONFO2) was separately estimated by the confinement method. {Mdot}CONFO2 subtracted from {Mdot}TOTO2 approximates {Mdot}CBO2, the O2 uptake rate necessary to activate the piston-pump breathing mechanism and to ensure the corresponding mechanical work rate, {Wdot}MEC. The results show that the energy cost of breathing, {Mdot}CBO2, of the piston-pump-breathing Arenicola is very high, with mean values approximating 47% of the {Mdot}TOTO2 value; that the mechanical power we measured, {Wdot}MEC, is very low; and that the mechanical-to-metabolic efficiency, the ratio {Wdot}MEC/{Mdot}CBO2, does not exceed 1%. These observations are compared to those obtained in other piston-pump breathers, such as Chaetopterus variopedatus and Urechis caupo, and in ciliary filter feeders including polychaetes, bivalves, and ascidians.
Accurate Determination of Tunneling-Affected Rate Coefficients: Theory Assessing Experiment.

PubMed

Zuo, Junxiang; Xie, Changjian; Guo, Hua; Xie, Daiqian

2017-07-20

The thermal rate coefficients of a prototypical bimolecular reaction are determined on an accurate ab initio potential energy surface (PES) using ring polymer molecular dynamics (RPMD). It is shown that quantum effects such as tunneling and zero-point energy (ZPE) are of critical importance for the HCl + OH reaction at low temperatures, while the heavier deuterium substitution renders tunneling less facile in the DCl + OH reaction. The calculated RPMD rate coefficients are in excellent agreement with experimental data for the HCl + OH reaction in the entire temperature range of 200-1000 K, confirming the accuracy of the PES. On the other hand, the RPMD rate coefficients for the DCl + OH reaction agree with some, but not all, experimental values. The self-consistency of the theoretical results thus allows a quality assessment of the experimental data.
A fractal analysis of pathogen detection by biosensors

NASA Astrophysics Data System (ADS)

Doke, Atul M.; Sadana, Ajit

2006-05-01

A fractal analysis is presented for the detection of pathogens such as Franscisela tularensis, and Yersinia pestis (the bacterium that causes plague) using a CANARY (cellular analysis and notification of antigens risks and yields) biosensor (Rider et al., 2003). In general, the binding and dissociation rate coefficients may be adequately described by either a single- or a dual-fractal analysis. An attempt is made to relate the binding rate coefficient to the degree of heterogeneity (fractal dimension value) present on the biosensor surface. Binding and dissociation rate coefficient values obtained are presented. The kinetics aspects along with the affinity values presented are of interest, and should along with the rate coefficients presented for the binding and the dissociation phase be of significant interest in help designing better biosensors for an application area that is bound to gain increasing importance in the future.
Data on inelastic processes in low-energy potassium-hydrogen and rubidium-hydrogen collisions

NASA Astrophysics Data System (ADS)

Yakovleva, S. A.; Barklem, P. S.; Belyaev, A. K.

2018-01-01

Two sets of rate coefficients for low-energy inelastic potassium-hydrogen and rubidium-hydrogen collisions were computed for each collisional system based on two model electronic structure calculations, performed by the quantum asymptotic semi-empirical and the quantum asymptotic linear combinations of atomic orbitals (LCAO) approaches, followed by quantum multichannel calculations for the non-adiabatic nuclear dynamics. The rate coefficients for the charge transfer (mutual neutralization, ion-pair formation), excitation and de-excitation processes are calculated for all transitions between the five lowest lying covalent states and the ionic states for each collisional system for the temperature range 1000-10 000 K. The processes involving higher lying states have extremely low rate coefficients and, hence, are neglected. The two model calculations both single out the same partial processes as having large and moderate rate coefficients. The largest rate coefficients correspond to the mutual neutralization processes into the K(5s 2S) and Rb(4d 2D) final states and at temperature 6000 K have values exceeding 3 × 10-8 cm3 s-1 and 4 × 10-8 cm3 s-1, respectively. It is shown that both the semi-empirical and the LCAO approaches perform equally well on average and that both sets of atomic data have roughly the same accuracy. The processes with large and moderate rate coefficients are likely to be important for non-LTE modelling in atmospheres of F, G and K-stars, especially metal-poor stars.
Rotational excitation of HCN by para- and ortho-H₂.

PubMed

Vera, Mario Hernández; Kalugina, Yulia; Denis-Alpizar, Otoniel; Stoecklin, Thierry; Lique, François

2014-06-14

Rotational excitation of the hydrogen cyanide (HCN) molecule by collisions with para-H2(j = 0, 2) and ortho-H2(j = 1) is investigated at low temperatures using a quantum time independent approach. Both molecules are treated as rigid rotors. The scattering calculations are based on a highly correlated ab initio 4-dimensional (4D) potential energy surface recently published. Rotationally inelastic cross sections among the 13 first rotational levels of HCN were obtained using a pure quantum close coupling approach for total energies up to 1200 cm(-1). The corresponding thermal rate coefficients were computed for temperatures ranging from 5 to 100 K. The HCN rate coefficients are strongly dependent on the rotational level of the H2 molecule. In particular, the rate coefficients for collisions with para-H2(j = 0) are significantly lower than those for collisions with ortho-H2(j = 1) and para-H2(j = 2). Propensity rules in favor of even Δj transitions were found for HCN in collisions with para-H2(j = 0) whereas propensity rules in favor of odd Δj transitions were found for HCN in collisions with H2(j ⩾ 1). The new rate coefficients were compared with previously published HCN-para-H2(j = 0) rate coefficients. Significant differences were found due the inclusion of the H2 rotational structure in the scattering calculations. These new rate coefficients will be crucial to improve the estimation of the HCN abundance in the interstellar medium.
Rapid Acute Dose Assessment Using MCNP6

NASA Astrophysics Data System (ADS)

Owens, Andrew Steven

Acute radiation doses due to physical contact with a high-activity radioactive source have proven to be an occupational hazard. Multiple radiation injuries have been reported due to manipulating a radioactive source with bare hands or by placing a radioactive source inside a shirt or pants pocket. An effort to reconstruct the radiation dose must be performed to properly assess and medically manage the potential biological effects from such doses. Using the reference computational phantoms defined by the International Commission on Radiological Protection (ICRP) and the Monte Carlo N-Particle transport code (MCNP6), dose rate coefficients are calculated to assess doses for common acute doses due to beta and photon radiation sources. The research investigates doses due to having a radioactive source in either a breast pocket or pants back pocket. The dose rate coefficients are calculated for discrete energies and can be used to interpolate for any given energy of photon or beta emission. The dose rate coefficients allow for quick calculation of whole-body dose, organ dose, and/or skin dose if the source, activity, and time of exposure are known. Doses are calculated with the dose rate coefficients and compared to results from the International Atomic Energy Agency (IAEA) reports from accidents that occurred in Gilan, Iran and Yanango, Peru. Skin and organ doses calculated with the dose rate coefficients appear to agree, but there is a large discrepancy when comparing whole-body doses assessed using biodosimetry and whole-body doses assessed using the dose rate coefficients.
Similarities and differences in mothers' and observers' ratings of infant security on the Attachment Q-Sort.

PubMed

Tarabulsy, George M; Provost, Marc A; Larose, Simon; Moss, Ellen; Lemelin, Jean-Pascal; Moran, Greg; Forbes, Lindsey; Pederson, David R

2008-01-01

This study examined the similarities and differences in maternal and observer Attachment Behavior Q-Sort ratings (AQS; Waters, 1995) and their relations to dimensions of the developmental ecology - maternal sensitivity, infant irritability, parental stress and psychosocial risk. Data was gathered from low risk (adult mothers; N=44) and high risk mother-infant dyads (adolescent mothers; N=83) when infants were aged 6, 10 and 15 months old, attachment being assessed at 15 months by both mothers and independent observers. A common factor was extracted from both sorts and served to operationalize the similarities between mother and observer ratings. Regressions were conducted to extract maternal and observer AQS scores that were unrelated to each other to represent the difference between the two sorts. Correlation analyses indicated that the common AQS factor was moderately linked to maternal sensitivity and parental stress, and showed a weak association to psychosocial risk and infant irritability. Residual maternal scores showed greater correlations with infant irritability and parental stress than did observer residual scores. Observer scores showed a greater correlation with psychosocial risk than maternal scores. Results suggest that common AQS variance presents a pattern of associations with ecological variables that is coherent with attachment research. Variance related to irritability, stress and risk appear to drive the differences between maternal and observer observations.

Behavioral and Self-report Measures Influencing Children’s Reported Attachment to Their Dog

PubMed Central

Hall, Nathaniel J.; Liu, Jingwen; Kertes, Darlene A.; Wynne, Clive D.L.

2016-01-01

Despite the prevalence of dogs as family pets and increased scientific interest in canine behavior, few studies have investigated characteristics of the child or dog that influence the child-dog relationship. In the present study, we explored how behavioral and self-report measures influence a child’s reported feelings of attachment to their dog, as assessed by the Lexington Attachment to Pets Scale (LAPS). We tested specifically whether children (N= 99; Age: M= 10.25 years, SD= 1.31 years) reported stronger attachment to dogs that were perceived as being more supportive (measured by a modified version of the Network of Relationships Inventory), to dogs that are more successful in following the child’s pointing gesture in a standard two-object choice test, or to dogs that solicited more petting in a sociability assessment. In addition, we assessed whether children’s attachment security to their parent, and whether being responsible for the care of their dog, influenced reported feelings of attachment to the dog. Overall, perceived support provided by the dog was highly predictive of all subscales of the LAPS. The dog’s success in following the child’s pointing gesture and lower rates of petting during the sociability assessment were associated with higher ratings on the general attachment subscale of the LAPS, but not of other subscales of the LAPS. Caring for the dog did not predict the child’s reported attachment to dog, but did predict the dog’s behavior on the point following task and petting during the sociability task. If the child cared for the dog, the dog was more likely to be successful on the pointing task and more likely to be petted. These results indicate a dyadic relationship in which the child’s care for the dog is associated with the dog’s behavior on the behavioral tasks, which in turn is related to the child’s reported feelings of attachment. The direction of influence and nature of this dyad will be a fruitful area for future research. PMID:28066130
Do Adolescents and Parents Reconstruct Memories about Their Conflict as a Function of Adolescent Attachment?

ERIC Educational Resources Information Center

Dykas, Matthew J.; Woodhouse, Susan S.; Ehrlich, Katherine B.; Cassidy, Jude

2010-01-01

This study examined whether 17-year-old adolescents (n = 189) and their parents reconstructed their memory for an adolescent-parent laboratory conflict over a 6-week period as a function of adolescent attachment organization. It also compared participants' perceptions of conflict over time to observational ratings of the conflict to further…
Attachment as Moderator of Treatment Outcome in Major Depression: A Randomized Control Trial of Interpersonal Psychotherapy versus Cognitive Behavior Therapy

ERIC Educational Resources Information Center

McBride, Carolina; Atkinson, Leslie; Quilty, Lena C.; Bagby, R. Michael

2006-01-01

Anxiety and avoidance dimensions of adult attachment insecurity were tested as moderators of treatment outcome for interpersonal psychotherapy (IPT) and cognitive-behavioral therapy (CBT). Fifty-six participants with major depression were randomly assigned to these treatment conditions. Beck Depression Inventory-II, Six-Item Hamilton Rating Scale…
Attachment Theory as a Predictor of Retention in First-Year College Students

ERIC Educational Resources Information Center

Hoyer, Matthew A.

2017-01-01

The prerequisite of a post-secondary education has grown at an unadulterated rate in the 21st century. During this time, research has clearly demonstrated the fundamental need of a healthy enduring relationship with a mother, father, partner, or friend through the psychological lens of attachment theory to auspiciously aid in the social and…
77 FR 20796 - Annual Updates to the Income Contingent Repayment (ICR) Plan Formula for 2011; William D. Ford...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-06

... Amounts General notes about the examples in this attachment: The interest rates used in the examples are... in this attachment. For married borrowers, the outstanding balance on the loans of each borrower and... proportion as that borrower's debt to the total outstanding balance. Each borrower is billed separately. For...
Place attachment and recreation demand on the west branch of the Farmington River

Treesearch

Jordan W. Smith; Roger L. Moore

2012-01-01

This paper analyzes the effect of place attachment on recreation demand for theWest Branch of the Farmington River. Data were collected via on-site and optional mail-back questionnaires administered to river recreationists during the summer of 2001. A total of 247 respondents (51 percent response rate) returned complete questionnaires. Questions concerned respondents...
Validity Evidence for the Security Scale as a Measure of Perceived Attachment Security in Adolescence

ERIC Educational Resources Information Center

Van Ryzin, Mark J.; Leve, Leslie D.

2012-01-01

In this study, the validity of a self-report measure of children's perceived attachment security (the Kerns Security Scale) was tested using adolescents. With regards to predictive validity, the Security Scale was significantly associated with (1) observed mother-adolescent interactions during conflict and (2) parent- and teacher-rated social…
Wing-Fixed PIV and force measurements of a large transverse gust encounter

NASA Astrophysics Data System (ADS)

Perrotta, Gino

2015-11-01

The unsteady aerodynamics of an aspect ratio 4 flat plate wing encountering a large-amplitude transverse gust were investigated using PIV in the wing-fixed reference frame and direct unsteady force measurements. Using a new experimental facility at the University of Maryland, the wing was towed at Reynolds number 20,000 through a 7m-long tank of nominally quiescent water containing a single cross-stream planar jet with velocity equal to the wing's towed velocity - a transverse gust ratio equal to one. The planar jet was created by pumping water through 30 cylindrical nozzles arranged in a single row. PIV confirms that the individual jets converge into a single, narrow, planar gust with a streamwise velocity profile resembling a canonical cosine-squared gust. Forces and fluid velocities of this wing-gust interaction will be presented for two pre-gust conditions: attached flow on the wing and stalled flow over the wing. In both cases, the gust encounter results in a momentary spike in lift coefficient. The peak lift coefficient was measured between 3 and 6 and varies with angle of attack. At low angle of attack, the attached flow wing produces less lift before the gust and much more (non-circulatory) lift during the gust than the stalled wing. Although the flow over the wing at low angle of attack separates during the gust and reattaches afterwards, the recovery time is similar to that of the high angle case, on the order of 10 chord lengths travelled.
Understanding Response Rates to Surveys About Family Members' Psychological Symptoms After Patients' Critical Illness.

PubMed

Long, Ann C; Downey, Lois; Engelberg, Ruth A; Nielsen, Elizabeth; Ciechanowski, Paul; Curtis, J Randall

2017-07-01

Achieving adequate response rates from family members of critically ill patients can be challenging, especially when assessing psychological symptoms. To identify factors associated with completion of surveys about psychological symptoms among family members of critically ill patients. Using data from a randomized trial of an intervention to improve communication between clinicians and families of critically ill patients, we examined patient-level and family-level predictors of the return of usable surveys at baseline, three months, and six months (n = 181, 171, and 155, respectively). Family-level predictors included baseline symptoms of psychological distress, decisional independence preference, and attachment style. We hypothesized that family with fewer symptoms of psychological distress, a preference for less decisional independence, and secure attachment style would be more likely to return questionnaires. We identified several predictors of the return of usable questionnaires. Better self-assessed family member health status was associated with a higher likelihood and stronger agreement with a support-seeking attachment style with a lower likelihood, of obtaining usable baseline surveys. At three months, family-level predictors of return of usable surveys included having usable baseline surveys, status as the patient's legal next of kin, and stronger agreement with a secure attachment style. The only predictor of receipt of surveys at six months was the presence of usable surveys at three months. We identified several predictors of the receipt of surveys assessing psychological symptoms in family of critically ill patients, including family member health status and attachment style. Using these characteristics to inform follow-up mailings and reminders may enhance response rates. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Comparison of nitrogen removal rates and nitrous oxide production from enriched anaerobic ammonium oxidizing bacteria in suspended and attached growth reactors.

PubMed

Panwivia, Supaporn; Sirvithayapakorn, Sanya; Wantawin, Chalermraj; Noophan, Pongsak Lek; Munakata-Marr, Junko

2014-01-01

Attached growth-systems for the anaerobic ammonium oxidation (anammox) process have been postulated for implementation in the field. However, information about the anammox process in attached growth-systems is limited. This study compared nitrogen removal rates and nitrous oxide (N2O) production of enriched anammox cultures in both suspended and attached growth sequencing batch reactors (SBRs). Suspended growth reactors (SBR-S) and attached growth reactors using polystyrene sponge as a medium (SBR-A) were used in these experiments. After inoculation with an enriched anammox culture, significant nitrogen removals of ammonium (NH4 (+)) and nitrite (NO2 (-)) were observed under NH4 (+):NO2 (-) ratios ranging from 1:1 to 1:2 in both types of SBRs. The specific rates of total nitrogen removal in SBR-S and SBR-A were 0.52 mg N/mg VSS-d and 0.44 mg N/mg VSS-d, respectively, at an NH4 (+):NO2 (-) ratio of 1:2. N2O production by the enriched anammox culture in both SBR-S and SBR-A was significantly higher at NH4 (+):NO2 (-) ratio of 1:2 than at NH4 (+):NO2 (-) ratios of 1:1 and 1:1.32. In addition, N2O production was higher at a pH of 6.8 than at pH 7.3, 7.8, and 8.3 in both SBR-S and SBR-A. The results of this investigation demonstrate that the anammox process may avoid N2O emission by maintaining an NH4 (+):NO2 (-) ratio of less than 1:2 and pH higher than 6.8.
Direct Simulation of Evolution and Control of Three-Dimensional Instabilities in Attachment-Line Boundary Layers

NASA Technical Reports Server (NTRS)

Joslin, Ronald D.

1995-01-01

The spatial evolution of three-dimensional disturbances in an attachment-line boundary layer is computed by direct numerical simulation of the unsteady, incompressible Navier-Stokes equations. Disturbances are introduced into the boundary layer by harmonic sources that involve unsteady suction and blowing through the wall. Various harmonic- source generators are implemented on or near the attachment line, and the disturbance evolutions are compared. Previous two-dimensional simulation results and nonparallel theory are compared with the present results. The three-dimensional simulation results for disturbances with quasi-two-dimensional features indicate growth rates of only a few percent larger than pure two-dimensional results; however, the results are close enough to enable the use of the more computationally efficient, two-dimensional approach. However, true three-dimensional disturbances are more likely in practice and are more stable than two-dimensional disturbances. Disturbances generated off (but near) the attachment line spread both away from and toward the attachment line as they evolve. The evolution pattern is comparable to wave packets in at-plate boundary-layer flows. Suction stabilizes the quasi-two-dimensional attachment-line instabilities, and blowing destabilizes these instabilities; these results qualitatively agree with the theory. Furthermore, suction stabilizes the disturbances that develop off the attachment line. Clearly, disturbances that are generated near the attachment line can supply energy to attachment-line instabilities, but suction can be used to stabilize these instabilities.
Do large rate coefficients for ion-polar neutral reactions have a serious effect on chemical models of dense clouds?

NASA Technical Reports Server (NTRS)

Herbst, E.; Leung, C. M.

1986-01-01

In order to incorporate large ion-polar neutral rate coefficients into existing gas phase reaction networks, it is necessary to utilize simplified theoretical treatments because of the significant number of rate coefficients needed. The authors have used two simple theoretical treatments: the locked dipole approach of Moran and Hamill for linear polar neutrals and the trajectory scaling approach of Su and Chesnavich for nonlinear polar neutrals. The former approach is suitable for linear species because in the interstellar medium these are rotationally relaxed to a large extent and the incoming charged reactants can lock their dipoles into the lowest energy configuration. The latter approach is a better approximation for nonlinear neutral species, in which rotational relaxation is normally less severe and the incoming charged reactants are not as effective at locking the dipoles. The treatments are in reasonable agreement with more detailed long range theories and predict an inverse square root dependence on kinetic temperature for the rate coefficient. Compared with the locked dipole method, the trajectory scaling approach results in rate coefficients smaller by a factor of approximately 2.5.
Hyperfine excitation of C2H and C2D by para-H2

NASA Astrophysics Data System (ADS)

Dumouchel, Fabien; Lique, François; Spielfiedel, Annie; Feautrier, Nicole

2017-10-01

The [C2H]/[C2D] abundance ratio is a useful tool to explore the physical and chemical conditions of cold molecular clouds. Hence, an accurate determination of both the C2H and C2D abundances is of fundamental interest. Due to the low density of the interstellar medium, the population of the energy levels of the molecules is not at local thermodynamical equilibrium. Thus, the accurate modelling of the emission spectra requires the calculation of collisional rate coefficients with the most abundant interstellar species. Hence, we provide rate coefficients for the hyperfine excitation of C2H and C2D by para-H2(j=0), the most abundant collisional partner in cold molecular clouds. State-to-state rate coefficients between the lowest levels were computed for temperatures ranging from 5 to 80 K. For both isotopologues, the Δj = ΔF propensity rule is observed. The comparison between C2H and C2D rate coefficients shows that differences by up to a factor of two exist, mainly for Δj = ΔN = 1 transitions. The new rate coefficients will significantly help in the interpretation of recent observed spectra.
Structure dependence of the rate coefficients of hydroxyl radical+aromatic molecule reaction

NASA Astrophysics Data System (ADS)

Wojnárovits, László; Takács, Erzsébet

2013-06-01

The rate coefficients of hydroxyl radical addition to the rings of simple aromatic molecules (kOH) were evaluated based on the literature data. By analyzing the methods of kOH determination and the data obtained the most probable values were selected for the kOH's of individual compounds and thereby the most reliable dataset was created for monosubstituted aromatics and p-substituted phenols. For these compounds the rate coefficients fall in a narrow range between 2×109 mol-1 dm3 s-1 and 1×1010 mol-1 dm3 s-1. Although the values show some regular trend with the electron donating/withdrawing nature of the substituent, the log kOH-σp Hammett substituent constant plots do not give straight lines because these high kOH's are controlled by both, the chemical reactivity and the diffusion. However, the logarithms of the rate coefficients of the chemical reactivity controlled reactions (kchem), are calculated by the equation 1/kOH=1/kchem+1/kdiff, and accepting for the diffusion controlled rate coefficient kdiff=1.1×1010 mol-1 dm3 s-1, show good linear correlation with σp.
Triplet Transport to and Trapping by Acceptor End Groups on Conjugated Polyfluorene Chains

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sreearunothai, P.; Miller, J.; Estrada, A.

2011-08-31

Triplet excited states created in polyfluorene (pF) molecules having average lengths up to 170 repeat units were transported to and captured by trap groups at the ends in less {approx}40 ns. Almost all of the triplets attached to the chains reached the trap groups, ruling out the presence of substantial numbers of defects that prevent transport. The transport yields a diffusion coefficient D of at least 3 x 10{sup -4} cm{sup 2} s{sup -1}, which is 30 times typical molecular diffusion and close to a value for triplet transport reported by Keller (J. Am. Chem. Soc.2011, 133, 11289-11298). The tripletmore » states were created in solution by pulse radiolysis; time resolution was limited by the rate of attachment of triplets to the pF chains. Naphthylimide (NI) or anthraquinone (AQ) groups attached to the ends of the chains acted as traps for the triplets, although AQ would not have been expected to serve as a trap on the basis of triplet energies of the separate molecules. The depths of the NI and AQ triplet traps were determined by intermolecular triplet transfer equilibria and temperature dependence. The trap depths are shallow, just a few times thermal energy for both, so a small fraction of the triplets reside in the pF chains in equilibrium with the end-trapped triplets. Trapping by AQ appears to arise from charge transfer interactions between the pF chains and the electron-accepting AQ groups. Absorption bands of the end-trapped triplet states are similar in peak wavelength (760 nm) and shape to the 760 nm bands of triplets in the pF chains but have reduced intensities. When an electron donor, N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), is added to the solution, it reacts with the end-trapped triplets to remove the 760 nm bands and to make the trapping irreversible. New bands created upon reaction with TMPD may be due to charge transfer states.« less
Degradation phenomena of magnetic attachments used clinically in the oral environment

NASA Astrophysics Data System (ADS)

Chung, Chae-Heon; Choe, Han-Cheol; Kwak, Jong-Ha

2006-08-01

The purpose of this study was to investigate the mechanisms involved in the failure of magnetic attachments used to retain dental prostheses. Dyna magnets were retrieved from dentures that had failed after 34 months of clinical use. These magnetic attachments were prepared and sectioned so as to observe the corrosion surface and layer in order to analyze the corrosion behaviors of the attachments. The corroded surface was observed under a field emission scanning electron microscope (FE-SEM) (JSM 840A, JEOL, Japan). An X-ray diffractometer (XRD) was used to analyze the corrosion product formed due to corrosion in the oral environment. Erosion-corrosion started in the uneven portion of the stainless steel cover in the magnetic attachments composed with Nd-Fe-B alloy. Corrosion was initiated on the worn stainless steel surface, followed by spalling of magnetic material due to corrosive solution. The corrosion rate increased drastically after the corrosion product caused spalling in Nd-Fe-B alloy. Corrosion initiated in the uneven stainless steel surface as well as in the welded zone. In conclusion, the failure of magnetic attachments may occur by either welding failure or breakdown of the encapsulating material. Thus, we believe that treating the surface of magnetic attachments would resolve the corrosion problem seen in magnetic attachments to some extent.
Two part condenser for varying the rate of condensing and related method

DOEpatents

Dobos, James G.

2007-12-11

A heat transfer apparatus, such as a condenser, is provided. The apparatus includes a first component with a first heat transfer element that has first component inlet and outlet ports through which a first fluid may pass. A second component is also included and likewise has a second heat transfer element with second component inlet and outlet ports to pass a second fluid. The first component has a body that can receive a third fluid for heat transfer with the first heat transfer element. The first and second components are releasably attachable with one another so that when attached both the first and second heat transfer elements effect heat transfer with the third fluid. Attachment and removal of the first and second components allows for the heat transfer rate of the apparatus to be varied. An associated method is also provided.
Dissociative electron attachment to C{sub 2}F{sub 5} radicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haughey, Sean A.; Field, Thomas A.; Langer, Judith

Dissociative electron attachment to the reactive C{sub 2}F{sub 5} molecular radical has been investigated with two complimentary experimental methods; a single collision beam experiment and a new flowing afterglow Langmuir probe technique. The beam results show that F{sup -} is formed close to zero electron energy in dissociative electron attachment to C{sub 2}F{sub 5}. The afterglow measurements also show that F{sup -} is formed in collisions between electrons and C{sub 2}F{sub 5} molecules with rate constants of 3.7 Multiplication-Sign 10{sup -9} cm{sup 3} s{sup -1} to 4.7 Multiplication-Sign 10{sup -9} cm{sup 3} s{sup -1} at temperatures of 300-600 K. Themore » rate constant increases slowly with increasing temperature, but the rise observed is smaller than the experimental uncertainty of 35%.« less
The origin of asymmetric behavior of money flow in the business firm network

NASA Astrophysics Data System (ADS)

Miura, W.; Takayasu, H.; Takayasu, M.

2012-09-01

In the business firm network, the number of in-degrees and out-degrees show the same scale-free property, however, the distribution of authorities and hubs show asymmetric behavior. Here we show the result of an analysis of the two-link structure of the network to find the origin of this asymmetric behavior. We find the tendency for big construction firms intermediating small subcontracting firms to have higher hub degrees. By measuring the strength of preferential attachment rate of new companies, we also find a abnormally strong preferential attachment for which the exponent is 1.4 with respect to out-degree when a new company forms a business partnership with a construction company. We propose a new model that reproduces the asymmetric behavior of the degrees of authorities and hubs by changing the preferential attachment rate between the in-degree and the out-degree in the business firm network.
Struvite formation and the fouling propensity of different materials.

PubMed

Doyle, J D; Oldring, K; Churchley, J; Parsons, S A

2002-09-01

Struvite (MgNH4PO4 x 6H2O) fouling was investigated to identify the impact supersaturation and material had on scaling rates. Tests were undertaken at three supersaturation ratios and with three different materials: stainless steel, teflon and acrylic. Impellers consisting of a clasp unit and two corrosion coupons that could be attached were used to mix centrate liquor and precipitation was initiated by the change in pH caused by degassing. Increasing the supersaturation ratio from 1.7 to 5.3 led to a doubling in the scaling rate of stainless-steel coupons. Experiments with acrylic and teflon coupons showed the influence of surface roughness upon scaling propensity. Coarsely roughened coupons following 40 h of mixing had a mass of 413 mg of struvite attached compared to smooth coupons that had a mass of 240 mg attached. Material did have an influence upon struvite fouling but this influence diminished with increasing surface roughness.

Understanding the Elementary Steps in DNA Tile-Based Self-Assembly.

PubMed

Jiang, Shuoxing; Hong, Fan; Hu, Huiyu; Yan, Hao; Liu, Yan

2017-09-26

Although many models have been developed to guide the design and implementation of DNA tile-based self-assembly systems with increasing complexity, the fundamental assumptions of the models have not been thoroughly tested. To expand the quantitative understanding of DNA tile-based self-assembly and to test the fundamental assumptions of self-assembly models, we investigated DNA tile attachment to preformed "multi-tile" arrays in real time and obtained the thermodynamic and kinetic parameters of single tile attachment in various sticky end association scenarios. With more sticky ends, tile attachment becomes more thermostable with an approximately linear decrease in the free energy change (more negative). The total binding free energy of sticky ends is partially compromised by a sequence-independent energy penalty when tile attachment forms a constrained configuration: "loop". The minimal loop is a 2 × 2 tetramer (Loop4). The energy penalty of loops of 4, 6, and 8 tiles was analyzed with the independent loop model assuming no interloop tension, which is generalizable to arbitrary tile configurations. More sticky ends also contribute to a faster on-rate under isothermal conditions when nucleation is the rate-limiting step. Incorrect sticky end contributes to neither the thermostability nor the kinetics. The thermodynamic and kinetic parameters of DNA tile attachment elucidated here will contribute to the future improvement and optimization of tile assembly modeling, precise control of experimental conditions, and structural design for error-free self-assembly.
Experimental determination of the Yawing Moment due to Yawing Contributed by the Wing, Fuselage, and Vertical Tail of a Midwing Airplane Model

DTIC Science & Technology

1943-06-01

derivative Cnr, the rate of change of yawing-momer.t coefficient with yawing angular velocity, contributed ’by the wing, the fuselage, and the...derivative Cn , the rate of change of yawing--moraent coefficient with yawing angular velocity. Al- though theoretical methods for obtaining the...yaw. T CD -3 SYMBOLS ’n rate of change of yawing-moment coefficient with yawing angular velocity per unit of rh/2V ÖCn/d (^-’ \\ 27 J P
On the role of vibrational excitation in dissociative recombination

NASA Technical Reports Server (NTRS)

Cunningham, A. J.; Omalley, T. F.; Hobson, R. M.

1981-01-01

An improved physical model of dissociative recombination is presented and applied to experimental data on the temperature dependence of rate coefficients for the rare-gas and atmospheric-gas ions. It is shown that in the charge neutralisation of the rare-gas dimer ions, autoionisation plays an important role (at least in comparison with the atmospheric-gas ions) and contributes to the fast fall-off in the rate coefficient with vibrational excitation observed in shock tube studies. Numerical estimates of the observed fall-off in rate coefficient with increasing vibrational excitation are also presented.
Efficient calculation of atomic rate coefficients in dense plasmas

NASA Astrophysics Data System (ADS)

Aslanyan, Valentin; Tallents, Greg J.

2017-03-01

Modelling electron statistics in a cold, dense plasma by the Fermi-Dirac distribution leads to complications in the calculations of atomic rate coefficients. The Pauli exclusion principle slows down the rate of collisions as electrons must find unoccupied quantum states and adds a further computational cost. Methods to calculate these coefficients by direct numerical integration with a high degree of parallelism are presented. This degree of optimization allows the effects of degeneracy to be incorporated into a time-dependent collisional-radiative model. Example results from such a model are presented.
Vibrational Relaxation and Electronic Quenching-Rate Coefficients for BiF (A0+,v1) by SF6

DTIC Science & Technology

1988-08-22

REPORT SD-TR-88-83 LO Vibrational Relaxation and Electronic Quenching-Rate N Coefficients for BiF (AO+ , v ) by SF 6 0) 0) H . HELVAJIAN , J. S...1. J. M. Herbelin and R. A. Klingberg, Int. J. Chem. Kinet. 16, 849 (19824). 2. R. F. Heidner III, H . Helvajian , J. S. Holloway, and J. B. Koffend, J...driven electronic-transfer laser based on the efficient H + NF2 NF(a) + HF reaction. More recently, the rate coefficients for spontaneous emission
Analysis of the Lankford coefficient evolution at different strain rates for AA6016-T4, DP800 and DC06

NASA Astrophysics Data System (ADS)

Lenzen, Matthias; Merklein, Marion

2017-10-01

In the automotive sector, a major challenge is the deep-drawing of modern lightweight sheet metals with limited formability. Thus, conventional material models lack in accuracy due to the complex material behavior. A current field of research takes into account the evolution of the Lankford coefficient. Today, changes in anisotropy under increasing degree of deformation are not considered. Only a consolidated average value of the Lankford coefficient is included in conventional material models. This leads to an increasing error in prediction of the flow behavior and therefore to an inaccurate prognosis of the forming behavior. To increase the accuracy of the prediction quality, the strain dependent Lankford coefficient should be respected, because the R-value has a direct effect on the contour of the associated flow rule. Further, the investigated materials show a more or less extinct rate dependency of the yield stress. For this reason, the rate dependency of the Lankford coefficient during uniaxial tension is focused within this contribution. To quantify the influence of strain rate on the Lankford coefficient, tensile tests are performed for three commonly used materials, the aluminum alloy AA6016-T4, the advanced high strength steel DP800 and the deep drawing steel DC06 at three different strain rates. The strain measurement is carried out by an optical strain measurement system. An evolution of the Lankford coefficient was observed for all investigated materials. Also, an influence of the deformation velocity on the anisotropy could be detected.
The structure of turbulent flow around vertical plates containing holes and attached to a channel bed

NASA Astrophysics Data System (ADS)

Basnet, K.; Constantinescu, G.

2017-11-01

High-resolution, 3-D large eddy simulations are conducted to study the physics of flow past 2-D solid and porous vertical plates of height H mounted on a horizontal surface (no bottom gap) with a fully developed, turbulent incoming flow. The porous plate consists of an array of spanwise-oriented, identical solid cylinders of rectangular cross section. The height of the solid cylinders and the spacing between the solid cylinders, corresponding to the plate's "holes," are kept constant for any given configuration, as the present study considers only plates of uniform porosity. The paper discusses how the mean flow and turbulence structure around the vertical plate, the unsteady forces acting on the plate, the dynamics of the large-scale turbulent eddies, the spectral content of the wake, and the distribution of the bed friction velocity on the horizontal channel bed vary as a function of the plate porosity (0% < P < 36%), the relative spacing between the solid elements of the porous plate (d/H), and the roughness of the channel bed surface. Simulation results are used to explain how the bleeding flow affects the dynamics on the larger billow eddies advected in the separated shear layer (SSL) forming at the top of the plate and the wake structure. It is found that the main recirculation eddy in the wake remains attached to the plate for P < 30%. For larger porosities, the main recirculation eddy forms away from the porous plate. The energy of the billows advected in the SSL decays monotonically with increasing plate porosity. For cases when the recirculation eddy remains attached to the plate, the larger billows advected in the downstream part of the SSL are partially reinjected inside the main recirculation eddy as a result of their interaction with the channel bed. This creates a feedback mechanism that induces large-scale disturbances of the spanwise-oriented vortex tubes advected inside the upstream part of the SSL. Results also show that the mean drag coefficient and the root-mean-square of the drag coefficient fluctuations increase mildly with increasing d/H. Meanwhile, varying d/H has a negligible effect on the position and size of the main recirculation eddy. The presence of large-scale roughness elements (2-D ribs) at the bed results in the decrease of the mean drag coefficient of the plate and, in the case of a solid plate, in a large decrease of the frequency of the large-scale eddies advected in the SSL.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Golubev, A.; Balashov, Y.; Mavrin, S.

Washout coefficient Λ is widely used as a parameter in washout models. These models describes overall HTO washout with rain by a first-order kinetic equation, while washout coefficient Λ depends on the type of rain event and rain intensity and empirical parameters a, b. The washout coefficient is a macroscopic parameter and we have considered in this paper its relationship with a microscopic rate K of HTO isotopic exchange in atmospheric humidity and drops of rainwater. We have shown that the empirical parameters a, b can be represented through the rain event characteristics using the relationships of molecular impact rate,more » rain intensity and specific rain water content while washout coefficient Λ can be represented through the exchange rate K, rain intensity, raindrop diameter and terminal raindrop velocity.« less
Blood pressure variability in man: its relation to high blood pressure, age and baroreflex sensitivity.

PubMed

Mancia, G; Ferrari, A; Gregorini, L; Parati, G; Pomidossi, G; Bertinieri, G; Grassi, G; Zanchetti, A

1980-12-01

1. Intra-arterial blood pressure and heart rate were recorded for 24 h in ambulant hospitalized patients of variable age who had normal blood pressure or essential hypertension. Mean 24 h values, standard deviations and variation coefficient were obtained as the averages of values separately analysed for 48 consecutive half-hour periods. 2. In older subjects standard deviation and variation coefficient for mean arterial pressure were greater than in younger subjects with similar pressure values, whereas standard deviation and variation coefficient for mean arterial pressure were greater than in younger subjects with similar pressure values, whereas standard deviation aations and variation coefficient were obtained as the averages of values separately analysed for 48 consecurive half-hour periods. 2. In older subjects standard deviation and variation coefficient for mean arterial pressure were greater than in younger subjects with similar pressure values, whereas standard deviation and variation coefficient for heart rate were smaller. 3. In hypertensive subjects standard deviation for mean arterial pressure was greater than in normotensive subjects of similar ages, but this was not the case for variation coefficient, which was slightly smaller in the former than in the latter group. Normotensive and hypertensive subjects showed no difference in standard deviation and variation coefficient for heart rate. 4. In both normotensive and hypertensive subjects standard deviation and even more so variation coefficient were slightly or not related to arterial baroreflex sensitivity as measured by various methods (phenylephrine, neck suction etc.). 5. It is concluded that blood pressure variability increases and heart rate variability decreases with age, but that changes in variability are not so obvious in hypertension. Also, differences in variability among subjects are only marginally explained by differences in baroreflex function.
Joint estimation of preferential attachment and node fitness in growing complex networks

NASA Astrophysics Data System (ADS)

Pham, Thong; Sheridan, Paul; Shimodaira, Hidetoshi

2016-09-01

Complex network growth across diverse fields of science is hypothesized to be driven in the main by a combination of preferential attachment and node fitness processes. For measuring the respective influences of these processes, previous approaches make strong and untested assumptions on the functional forms of either the preferential attachment function or fitness function or both. We introduce a Bayesian statistical method called PAFit to estimate preferential attachment and node fitness without imposing such functional constraints that works by maximizing a log-likelihood function with suitably added regularization terms. We use PAFit to investigate the interplay between preferential attachment and node fitness processes in a Facebook wall-post network. While we uncover evidence for both preferential attachment and node fitness, thus validating the hypothesis that these processes together drive complex network evolution, we also find that node fitness plays the bigger role in determining the degree of a node. This is the first validation of its kind on real-world network data. But surprisingly the rate of preferential attachment is found to deviate from the conventional log-linear form when node fitness is taken into account. The proposed method is implemented in the R package PAFit.
Interaction of recalled parental ADHD symptoms and rearing behavior with current attachment and emotional dysfunction in adult offspring with ADHD.

PubMed

Edel, Marc-Andreas; Juckel, Georg; Brüne, Martin

2010-06-30

Research into attachment and emotion regulation has shown that children with ADHD are at risk of developing attachment disorders and emotion regulation disturbances, which in part may be due to the rearing style of their parents. No such data exists for adults with persistent ADHD. We hypothesized that current attachment style and emotion processing of adult patients with ADHD may be influenced by the presence of parental ADHD symptoms when the now adult patients were children, assuming that ADHD symptoms of parents have an impact on their parenting style. We examined recalled parental ADHD symptoms and rearing style as well as current attachment and emotion regulation abilities in a sample of 73 adults with ADHD using several self-rating instruments. Recalled prevalence of ADHD symptoms in the mother, and less so in the father, of adult patients with ADHD was significantly associated with partly adverse parental rearing styles, current attachment problems in romantic partnerships and emotion regulation disturbances compared with adult ADHD patients without possibly affected parent. ADHD symptoms in parents of children with ADHD may present a risk factor for attachment problems and poor emotion regulation when ADHD children are grown.
Attachment in middle childhood: predictors, correlates, and implications for adaptation.

PubMed

Boldt, Lea J; Kochanska, Grazyna; Grekin, Rebecca; Brock, Rebecca L

2016-01-01

Middle childhood is a relative lacuna in behavioral attachment research. We examined antecedents, correlates, and implications of parent-child attachment at age 10 in a longitudinal study of community families from a Midwestern US state (N = 102, mothers, fathers, and children). Dimensions of security, avoidance, ambivalence, and disorganization of children's attachment to each parent were observed in lengthy naturalistic interactions and assessed using Iowa Attachment Behavioral Coding (IABC). IABC scores were meaningfully associated with history of parental responsiveness (7-80 months) and with earlier and concurrent attachment security, assessed with other established instruments (parent- and observer-rated Attachment Q-Set at 25 months, children's reports at age 8 and 10). Structural equation modeling analyses revealed that the overall history of responsive care was meaningfully associated with Security, Avoidance, and Disorganization at age 10, in both mother-child and father-child relationships, and that most recent care uniquely predicted Security. IABC scores were also meaningfully related to a broad range of measures of child adaptation at ages 10-12. Cumulative history of children's security from infancy to middle childhood, integrating measures across relationships and methodologies, also predicted child adaptation at ages 10-12.
Attachment in Middle Childhood: Predictors, Correlates, and Implications for Adaptation

PubMed Central

Boldt, Lea J.; Kochanska, Grazyna; Grekin, Rebecca; Brock, Rebecca L.

2016-01-01

Middle childhood is a relative lacuna in behavioral attachment research. We examined antecedents, correlates, and implications of parent-child attachment at age 10 in a longitudinal study of community families from a Midwestern US state (N=102, mothers, fathers, and children). Dimensions of security, avoidance, ambivalence, and disorganization of children’s attachment to each parent were observed in lengthy naturalistic interactions and assessed using Iowa Attachment Behavioral Coding (IABC). IABC scores were meaningfully associated with history of parental responsiveness (7–80 months) and with earlier and concurrent attachment security, assessed with other established instruments (parent- and observer-rated Attachment Q-Set at 25 months, children’s reports at age 8 and 10). Structural equation modeling analyses revealed that the overall history of responsive care was meaningfully associated with Security, Avoidance, and Disorganization at age 10, in both mother-child and father-child relationships, and that most recent care uniquely predicted Security. IABC scores were also meaningfully related to a broad range of measures of child adaptation at ages 10–12. Cumulative history of children’s security from infancy to middle childhood, integrating measures across relationships and methodologies, also predicted child adaptation at ages 10–12. PMID:26673686
Joint estimation of preferential attachment and node fitness in growing complex networks

PubMed Central

Pham, Thong; Sheridan, Paul; Shimodaira, Hidetoshi

2016-01-01

Complex network growth across diverse fields of science is hypothesized to be driven in the main by a combination of preferential attachment and node fitness processes. For measuring the respective influences of these processes, previous approaches make strong and untested assumptions on the functional forms of either the preferential attachment function or fitness function or both. We introduce a Bayesian statistical method called PAFit to estimate preferential attachment and node fitness without imposing such functional constraints that works by maximizing a log-likelihood function with suitably added regularization terms. We use PAFit to investigate the interplay between preferential attachment and node fitness processes in a Facebook wall-post network. While we uncover evidence for both preferential attachment and node fitness, thus validating the hypothesis that these processes together drive complex network evolution, we also find that node fitness plays the bigger role in determining the degree of a node. This is the first validation of its kind on real-world network data. But surprisingly the rate of preferential attachment is found to deviate from the conventional log-linear form when node fitness is taken into account. The proposed method is implemented in the R package PAFit. PMID:27601314
The development of an estimation model for energy expenditure during water walking by acceleration and walking speed.

PubMed

Kaneda, Koichi; Ohgi, Yuji; Tanaka, Chiaki; Burkett, Brendan

2014-01-01

The aim of this study was to develop an estimation equation for energy expenditure during water walking based on the acceleration and walking speed. Cross-validation study. Fifty participants, males (n=29, age: 27-73) and females (n=21, age: 33-70) volunteered for this study. Based on their physical condition water walking was conducted at three self-selected walking speeds from a range of: 20, 25, 30, 35 and 40 m/min. Energy expenditure during each trial was calculated. During water walking, an accelerometer was attached to the occipital region and recorded three-dimensional accelerations at 100 Hz. A stopwatch was used for timing the participant's walking speed. The estimation model for energy expenditure included three components; (i) resting metabolic rate, (ii) internal energy expenditure for moving participants' body, and (iii) external energy expenditure due to water drag force. When comparing the measured and estimated energy expenditure with the acceleration data being the third component of the estimation model, high correlation coefficients were found in both male (r=0.73) and female (r=0.77) groups. When walking speeds were applied to the third component of the model, higher correlation coefficients were found (r=0.82 in male and r=0.88 in female). Good agreements of the developed estimation model were found in both methods, regardless of gender. This study developed a valid estimation model for energy expenditure during water walking by using head acceleration and walking speed. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Atomic data on inelastic processes in low-energy manganese-hydrogen collisions

NASA Astrophysics Data System (ADS)

Belyaev, Andrey K.; Voronov, Yaroslav V.

2017-10-01

Aims: The aim of this paper is to calculate cross sections and rate coefficients for inelastic processes in low-energy Mn + H and Mn+ + H- collisions, especially, for processes with high and moderate rate coefficients. These processes are required for non-local thermodynamic equilibrium (non-LTE) modeling of manganese spectra in cool stellar atmospheres, and in particular, for metal-poor stars. Methods: The calculations of the cross sections and the rate coefficients were performed by means of the quantum model approach within the framework of the Born-Oppenheimer formalism, that is, the asymptotic semi-empirical method for the electronic MnH molecular structure calculation followed by the nonadiabatic nuclear dynamical calculation by means of the multichannel analytic formulas. Results: The cross sections and the rate coefficients for low-energy inelastic processes in manganese-hydrogen collisions are calculated for all transitions between 21 low-lying covalent states and one ionic state. We show that the highest values of the cross sections and the rate coefficients correspond to the mutual neutralization processes into the final atomic states Mn(3d54s(7S)5s e 6S), Mn(3d54s(7S)5p y 8P°), Mn(3d54s(7S)5s e 8S), Mn(3d54s(7S)4d e 8D) [the first group], the processes with the rate coefficients (at temperature T = 6000 K) of the values 4.38 × 10-8, 2.72 × 10-8, 1.98 × 10-8, and 1.59 × 10-8 cm3/ s, respectively, that is, with the rate coefficients exceeding 10-8 cm3/ s. The processes with moderate rate coefficients, that is, with values between 10-10 and 10-8 cm3/ s include many excitation, de-excitation, mutual neutralization and ion-pair formation processes. In addition to other processes involving the atomic states from the first group, the processes from the second group include those involving the following atomic states: Mn(3d5(6S)4s4p (1P°) y 6P°), Mn(3d54s(7S)4d e 6D), Mn(3d54s(7S)5p w 6P°), Mn(3d5(4P)4s4p (3P°) y 6D°), Mn(3d5(4G)4s4p (3P°) y 6F°). The processes with the highest and moderate rate coefficients are expected to be important for non-LTE modeling of manganese spectra in stellar atmospheres. Rate coefficients Kif(T) for the excitation, de-excitation, mutual neutralization, and ion-pair formation processes in manganese-hydrogen collisions are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/606/A106
H2/O2 three-body rates at high temperatures

NASA Technical Reports Server (NTRS)

Marinelli, William J.; Kessler, William J.; Carleton, Karen L.

1991-01-01

Hydrogen atoms are produced in the presence of excess O2, and the first-order decay are studied as a function of temperature and pressure in order to obtain the rate coefficient for the three-body reaction between H-atoms and O2. Attention is focused on the kinetic scheme employed as well as the reaction cell and photolysis and probe laser system. A two-photon laser-induced fluorescence technique is employed to detect H-atoms without optical-thickness or O2-absorption problems. Results confirm measurements reported previously for the H + O2 + N2 reaction at 300 K and extend these measurements to higher temperatures. Preliminary data indicate non-Arrehenius-type behavior of this reaction rate coefficient as a function of temperature. Measurements of the rate coefficient for H + O2 + Ar reaction at 300 K give a rate coefficient of 2.1 +/- 0.1 x 10 to the -32nd cm exp 6/molecule sec.
A comparison of the reactivity of germylene and dimethylgermylene with some methylgermanes. Direct kinetic and quantum chemical studies.

PubMed

Becerra, Rosa; Boganov, Sergey E; Egorov, Mikhail P; Faustov, Valery I; Krylova, Irina V; Nefedov, Oleg M; Promyslov, Vladimir M; Walsh, Robin

2007-08-21

Time-resolved studies of germylene, GeH(2), and dimethygermylene, GeMe(2), generated by the 193 nm laser flash photolysis of appropriate precursor molecules have been carried out to try to obtain rate coefficients for their bimolecular reactions with dimethylgermane, Me(2)GeH(2), in the gas-phase. GeH(2) + Me(2)GeH(2) was studied over the pressure range 1-100 Torr with SF(6) as bath gas and at five temperatures in the range 296-553 K. Only slight pressure dependences were found (at 386, 447 and 553 K). RRKM modelling was carried out to fit these pressure dependences. The high pressure rate coefficients gave the Arrhenius parameters: log(A/cm(3) molecule(-1) s(-1)) = -10.99 +/- 0.07 and E(a) =-(7.35 +/- 0.48) kJ mol(-1). No reaction could be found between GeMe(2) + Me(2)GeH(2) at any temperature up to 549 K, and upper limits of ca. 10(-14) cm(3) molecule(-1) s(-1) were set for the rate coefficients. A rate coefficient of (1.33 +/- 0.04) x 10(-10) cm(3) molecule(-1) s(-1) was also obtained for GeH(2) + MeGeH(3) at 296 K. No reaction was found between GeMe(2) and MeGeH(3). Rate coefficient comparisons showed, inter alia, that in the substrate germane Me-for-H substitution increased the magnitudes of rate coefficients significantly, while in the germylene Me-for-H substitution decreased the magnitudes of rate coefficients by at least four orders of magnitude. Quantum chemical calculations (G2(MP2,SVP)//B3LYP level) supported these findings and showed that the lack of reactivity of GeMe(2) is caused by a positive energy barrier for rearrangement of the initially formed complexes. Full details of the structures of intermediate complexes and the discussion of their stabilities are given in the paper.
Exact free vibration of multi-step Timoshenko beam system with several attachments

NASA Astrophysics Data System (ADS)

Farghaly, S. H.; El-Sayed, T. A.

2016-05-01

This paper deals with the analysis of the natural frequencies, mode shapes of an axially loaded multi-step Timoshenko beam combined system carrying several attachments. The influence of system design and the proposed sub-system non-dimensional parameters on the combined system characteristics are the major part of this investigation. The effect of material properties, rotary inertia and shear deformation of the beam system for each span are included. The end masses are elastically supported against rotation and translation at an offset point from the point of attachment. A sub-system having two degrees of freedom is located at the beam ends and at any of the intermediate stations and acts as a support and/or a suspension. The boundary conditions of the ordinary differential equation governing the lateral deflections and slope due to bending of the beam system including the shear force term, due to the sub-system, have been formulated. Exact global coefficient matrices for the combined modal frequencies, the modal shape and for the discrete sub-system have been derived. Based on these formulae, detailed parametric studies of the combined system are carried out. The applied mathematical model is valid for wide range of applications especially in mechanical, naval and structural engineering fields.
Mother-child bonding assessment tools☆

PubMed Central

Perrelli, Jaqueline Galdino Albuquerque; Zambaldi, Carla Fonseca; Cantilino, Amaury; Sougey, Everton Botelho

2014-01-01

Objective: To identify and describe research tools used to evaluate bonding between mother and child up to one year of age, as well as to provide information on reliability and validity measures related to these tools. Data source: Research studies available on PUBMED, LILACS, ScienceDirect, PsycINFO and CINAHL databases with the following descriptors: mother-child relations and mother infant relationship, as well as the expressions validity, reliability and scale. Data synthesis: 23 research studies were selected and fully analyzed. Thirteen evaluation research tools were identified concerning mother and child attachment: seven scales, three questionnaires, two inventories and one observation method. From all tools analyzed, the Prenatal Attachment Inventory presented the higher validity and reliability measures to assess mother and fetus relation during pregnancy. Concerning the puerperal period, better consistency coefficients were found for Maternal Attachment Inventory and Postpartum Bonding Questionnaire. Besides, the last one revealed a higher sensibility to identify amenable and severe disorders in the affective relations between mother and child. Conclusions: The majority of research tools are reliable to study the phenomenon presented, although there are some limitations regarding the construct and criterion related to validity. In addition to this, only two of them are translated into Portuguese and adapted to women and children populations in Brazil, being a decisive gap to scientific production in this area. PMID:25479859

Sonography on injury of the medial patellofemoral ligament after acute traumatic lateral patellar dislocation: Injury patterns and correlation analysis with injury of articular cartilage of the inferomedial patella.

PubMed

Zhang, Guang-Ying; Zheng, Lei; Shi, Hao; Qu, Su-Hui; Ding, Hong-Yu

2013-12-01

The purpose of this study was to investigate the accuracy of high-frequency ultrasonography in the diagnosis of injuries of medial patellofemoral ligaments (MPFLs), analyse the characteristics of MPFL injury and correlations between injury of the MPFL and articular cartilage of the inferomedial patella in patients with acute traumatic lateral patellar dislocation. High-frequency sonographic images of 49 patients with acute traumatic lateral patellar dislocations treated surgically were reviewed. The χ(2) tests were performed for statistical analysis. Twenty-eight cases of complete MPFL tear and 21 cases of partial MPFL tear were identified in operation, with 27 cases of MPFL tear located at their femoral attachment, 21 cases of tear at the patellar attachment and one case of midsubstance tear. The diagnostic accuracy of sonography regarding partial MPFL tear and complete MPFL tear was 89.8% and 89.8%. Among the patients with MPFL tear at the patellar attachment, eight and six cases were concomitant with chondral and osteochondral lesions in the inferomedial patella, respectively, in contrast to nine and six cases in patients with MPFL tear at the femoral attachment, respectively. There was no significant difference between the two locations described above regarding the prevalence rates of chondral or osteochondral lesions of the inferomedial patella (P=0.732, P=0.614). Among the patients with complete MPFL tear, 12 and 10 cases were concomitant with chondral and osteochondral lesions in the inferomedial patella, respectively, while six and two cases were concomitant with partial MPFL tear. There was no significant difference between the two types of injuries discussed above on the prevalence rates of chondral lesions of the inferomedial patella (P=0.305), but the prevalence rate of osteochondral lesions between the two types of injuries discussed above was statistically different (P=0.035). The MPFL is most easily injured at the femoral attachment, secondly at the patellar attachment. High-frequency ultrasonography is an accurate method in the diagnosis of an MPFL tear. There are neither significant differences on the prevalence rates of chondral or osteochondral lesions of the inferomedial patella between locations of MPFL injuries, nor significant difference on the prevalence rates of chondral lesions between MPFL injury types; but the complete MPFL tear is more often concomitant with inferomedial patellar osteochondral lesions than the partial MPFL tear. Copyright © 2013 Elsevier Ltd. All rights reserved.
Accurate rates of the complex mechanisms for growth and dissolu-tion of minerals using a combination of rare event theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stack, Andrew G; Raiten, Paolo; Gale, Julian D.

2012-01-01

Mineral growth and dissolution are often treated as occurring via a single, reversible process that governs the rate of reaction. We show that multiple, distinct intermediate states can occur during both growth and dissolution. Specifically, we have used metadynamics, a method to efficiently explore the free energy landscape of a system, coupled to umbrella sampling and reactive flux calculations, to examine the mechanism and rates of attachment and detachment of a barium ion onto a stepped, barite (BaSO4) surface. The activation energies calculated for the rate limiting reactions, which are different for attachment and detachment, precisely match those measured experimentallymore » during both growth and dissolution. These results can potentially explain anomalous, non-steady state mineral reaction rates observed experimentally, and will enable the design of more efficient growth inhibitors and facilitate an understanding of the effect of impurities.« less
Stationary-Afterglow measurements of dissociative recombination of H2D+ and HD2+ ions

NASA Astrophysics Data System (ADS)

Dohnal, Petr; Kalosi, Abel; Plasil, Radek; Johnsen, Rainer; Glosik, Juraj

2016-09-01

Binary recombination rate coefficients of H2D+ and HD2+ ions have been measured at a temperature of 80 K in an afterglow plasma experiment in which the fractional abundances of H3+, H2D+, HD2+, and D3+ ions were varied by adjusting the [D2]/([D2] + [H2]) ratio of the neutral gas. The fractional abundances of the four ion species during the afterglow and their rotational states were determined in situ by continuous-wave cavity ring-down absorption spectroscopy (CRDS), using overtone transitions from the ground vibrational states of the ions. The experimentally determined recombination rate coefficients will be compared to results of advanced theoretical calculations and to the known H3+ and D3+ recombination rate coefficients. We conclude that the recombination coefficients depend only weakly on the isotopic composition. Astrophysical implications of the measured recombination rate coefficients will be also discussed. Work supported by: Czech Science Foundation projects GACR 14-14649P, GACR 15-15077S, GACR P209/12/0233, and by Charles University in Prague Project Nr. GAUK 692214.
Bacterial attachment to RO membranes surface-modified by concentration-polarization-enhanced graft polymerization.

PubMed

Bernstein, Roy; Belfer, Sofia; Freger, Viatcheslav

2011-07-15

Concentration polarization-enhanced radical graft polymerization, a facile surface modification technique, was examined as an approach to reduce bacterial deposition onto RO membranes and thus contribute to mitigation of biofouling. For this purpose an RO membrane ESPA-1 was surface-grafted with a zwitterionic and negatively and positively charged monomers. The low monomer concentrations and low degrees of grafting employed in modifications moderately reduced flux (by 20-40%) and did not affect salt rejection, yet produced substantial changes in surface chemistry, charge and hydrophilicity. The propensity to bacterial attachment of original and modified membranes was assessed using bacterial deposition tests carried out in a parallel plate flow setup using a fluorescent strain of Pseudomonas fluorescens. Compared to unmodified ESPA-1 the deposition (mass transfer) coefficient was significantly increased for modification with the positively charged monomer. On the other hand, a substantial reduction in bacterial deposition rates was observed for membranes modified with zwitterionic monomer and, still more, with very hydrophilic negatively charged monomers. This trend is well explained by the effects of surface charge (as measured by ζ-potential) and hydrophilicity (contact angle). It also well correlated with force distance measurements by AFM using surrogate spherical probes with a negative surface charge mimicking the bacterial surface. The positively charged surface showed a strong hysteresis with a large adhesion force, which was weaker for unmodified ESPA-1 and still weaker for zwitterionic surface, while negatively charged surface showed a long-range repulsion and negligible hysteresis. These results demonstrate the potential of using the proposed surface- modification approach for varying surface characteristics, charge and hydrophilicity, and thus minimizing bacterial deposition and potentially reducing propensity biofouling.
Implementing the undergraduate mini-CEX: a tailored approach at Southampton University.

PubMed

Hill, Faith; Kendall, Kathleen; Galbraith, Kevin; Crossley, Jim

2009-04-01

The mini-clinical evaluation exercise (mini-CEX) is widely used in the UK to assess clinical competence, but there is little evidence regarding its implementation in the undergraduate setting. This study aimed to estimate the validity and reliability of the undergraduate mini-CEX and discuss the challenges involved in its implementation. A total of 3499 mini-CEX forms were completed. Validity was assessed by estimating associations between mini-CEX score and a number of external variables, examining the internal structure of the instrument, checking competency domain response rates and profiles against expectations, and by qualitative evaluation of stakeholder interviews. Reliability was evaluated by overall reliability coefficient (R), estimation of the standard error of measurement (SEM), and from stakeholders' perceptions. Variance component analysis examined the contribution of relevant factors to students' scores. Validity was threatened by various confounding variables, including: examiner status; case complexity; attachment specialty; patient gender, and case focus. Factor analysis suggested that competency domains reflect a single latent variable. Maximum reliability can be achieved by aggregating scores over 15 encounters (R = 0.73; 95% confidence interval [CI] +/- 0.28 based on a 6-point assessment scale). Examiner stringency contributed 29% of score variation and student attachment aptitude 13%. Stakeholder interviews revealed staff development needs but the majority perceived the mini-CEX as more reliable and valid than the previous long case. The mini-CEX has good overall utility for assessing aspects of the clinical encounter in an undergraduate setting. Strengths include fidelity, wide sampling, perceived validity, and formative observation and feedback. Reliability is limited by variable examiner stringency, and validity by confounding variables, but these should be viewed within the context of overall assessment strategies.
Calmodulin enhances ribbon replenishment and shapes filtering of synaptic transmission by cone photoreceptors

PubMed Central

Parmelee, Caitlyn M.; Chen, Minghui; Cork, Karlene M.; Curto, Carina; Thoreson, Wallace B.

2014-01-01

At the first synapse in the vertebrate visual pathway, light-evoked changes in photoreceptor membrane potential alter the rate of glutamate release onto second-order retinal neurons. This process depends on the synaptic ribbon, a specialized structure found at various sensory synapses, to provide a supply of primed vesicles for release. Calcium (Ca2+) accelerates the replenishment of vesicles at cone ribbon synapses, but the mechanisms underlying this acceleration and its functional implications for vision are unknown. We studied vesicle replenishment using paired whole-cell recordings of cones and postsynaptic neurons in tiger salamander retinas and found that it involves two kinetic mechanisms, the faster of which was diminished by calmodulin (CaM) inhibitors. We developed an analytical model that can be applied to both conventional and ribbon synapses and showed that vesicle resupply is limited by a simple time constant, τ = 1/(Dρδs), where D is the vesicle diffusion coefficient, δ is the vesicle diameter, ρ is the vesicle density, and s is the probability of vesicle attachment. The combination of electrophysiological measurements, modeling, and total internal reflection fluorescence microscopy of single synaptic vesicles suggested that CaM speeds replenishment by enhancing vesicle attachment to the ribbon. Using electroretinogram and whole-cell recordings of light responses, we found that enhanced replenishment improves the ability of cone synapses to signal darkness after brief flashes of light and enhances the amplitude of responses to higher-frequency stimuli. By accelerating the resupply of vesicles to the ribbon, CaM extends the temporal range of synaptic transmission, allowing cones to transmit higher-frequency visual information to downstream neurons. Thus, the ability of the visual system to encode time-varying stimuli is shaped by the dynamics of vesicle replenishment at photoreceptor synaptic ribbons. PMID:25311636
Scavenging and recombination kinetics in a radiation spur: The successive ordered scavenging events

NASA Astrophysics Data System (ADS)

Al-Samra, Eyad H.; Green, Nicholas J. B.

2018-03-01

This study describes stochastic models to investigate the successive ordered scavenging events in a spur of four radicals, a model system based on a radiation spur. Three simulation models have been developed to obtain the probabilities of the ordered scavenging events: (i) a Monte Carlo random flight (RF) model, (ii) hybrid simulations in which the reaction rate coefficient is used to generate scavenging times for the radicals and (iii) the independent reaction times (IRT) method. The results of these simulations are found to be in agreement with one another. In addition, a detailed master equation treatment is also presented, and used to extract simulated rate coefficients of the ordered scavenging reactions from the RF simulations. These rate coefficients are transient, the rate coefficients obtained for subsequent reactions are effectively equal, and in reasonable agreement with the simple correction for competition effects that has recently been proposed.
Factors influencing indoor PM2.5 concentration in rural houses of northern China

NASA Astrophysics Data System (ADS)

Zhang, Xueyan; Chen, Bin

2018-02-01

In traditional houses in rural areas of Northern China, most traditional heating systems, heated by mini-stove in the kitchen, usually take agricultural residues as fuels resources. Besides, burning cave under the ground-floor of a rural house is also widely used. The higher PM2.5 concentration is crisis for human health. In this study, PM2.5 concentration, temperature, relative humidity inside and outside the houses have been measured, moreover the factors impact on I/O rate coefficient has been discussed. The results show that the I/O rate coefficient in the evening is 2.5 times greater than the I/O rate coefficient in the daytime. I/O rate coefficient of PM2.5 concentration is positive related to air temperature difference between indoor and outdoor. In addition, the impact of outdoor wind speed and predominant wind direction on the PM2.5 emission has been studied.
Comparison of monoenergetic photon organ dose rate coefficients for stylized and voxel phantoms submerged in air

DOE PAGES

Bellamy, Michael B.; Hiller, Mauritius M.; Dewji, Shaheen A.; ...

2016-02-01

As part of a broader effort to calculate effective dose rate coefficients for external exposure to photons and electrons emitted by radionuclides distributed in air, soil or water, age-specific stylized phantoms have been employed to determine dose coefficients relating dose rate to organs and tissues in the body. In this article, dose rate coefficients computed using the International Commission on Radiological Protection reference adult male voxel phantom are compared with values computed using the Oak Ridge National Laboratory adult male stylized phantom in an air submersion exposure geometry. Monte Carlo calculations for both phantoms were performed for monoenergetic source photonsmore » in the range of 30 keV to 5 MeV. Furthermore, these calculations largely result in differences under 10 % for photon energies above 50 keV, and it can be expected that both models show comparable results for the environmental sources of radionuclides.« less
Comparison of monoenergetic photon organ dose rate coefficients for stylized and voxel phantoms submerged in air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bellamy, Michael B.; Hiller, Mauritius M.; Dewji, Shaheen A.

As part of a broader effort to calculate effective dose rate coefficients for external exposure to photons and electrons emitted by radionuclides distributed in air, soil or water, age-specific stylized phantoms have been employed to determine dose coefficients relating dose rate to organs and tissues in the body. In this article, dose rate coefficients computed using the International Commission on Radiological Protection reference adult male voxel phantom are compared with values computed using the Oak Ridge National Laboratory adult male stylized phantom in an air submersion exposure geometry. Monte Carlo calculations for both phantoms were performed for monoenergetic source photonsmore » in the range of 30 keV to 5 MeV. Furthermore, these calculations largely result in differences under 10 % for photon energies above 50 keV, and it can be expected that both models show comparable results for the environmental sources of radionuclides.« less
Wind-Tunnel Investigation of a Balloon as a Towed Decelerator at Mach Numbers from 1.47 to 2.50

NASA Technical Reports Server (NTRS)

McShera, John T.; Keyes, J. Wayne

1961-01-01

A wind-tunnel investigation has been conducted to study the characteristics of a towed spherical balloon as a drag device at Mach numbers from 1.47 to 2.50, Reynolds numbers from 0.36 x 10(exp 6) to 1.0 x 10(exp 6) , and angles of attack from -15 to 15 deg. Towed spherical balloons were found to be stable at supersonic speeds. The drag coefficient of the balloon is reduced by the presence of a tow cable and a further reduction occurs with the addition of a payload. The balloon inflation pressure required to maintain an almost spherical shape is about equal to the free-stream dynamic pressure. Measured pressure and temperature distribution around the balloon alone were in fair agreement with predicted values. There was a pronounced decrease in the pressure coefficients on the balloon when attached to a tow cable behind a payload.
Psychophysical evaluation of a variable friction tactile interface

NASA Astrophysics Data System (ADS)

Samur, Evren; Colgate, J. Edward; Peshkin, Michael A.

2009-02-01

This study explores the haptic rendering capabilities of a variable friction tactile interface through psychophysical experiments. In order to obtain a deeper understanding of the sensory resolution associated with the Tactile Pattern Display (TPaD), friction discrimination experiments are conducted. During the experiments, subjects are asked to explore the glass surface of the TPaD using their bare index fingers, to feel the friction on the surface, and to compare the slipperiness of two stimuli, displayed in sequential order. The fingertip position data is collected by an infrared frame and normal and translational forces applied by the finger are measured by force sensors attached to the TPaD. The recorded data is used to calculate the coefficient of friction between the fingertip and the TPaD. The experiments determine the just noticeable difference (JND) of friction coefficient for humans interacting with the TPaD.
Patient preference and satisfaction with implant-supported mandibular overdentures retained with ball or locator attachments: a crossover clinical trial.

PubMed

Krennmair, Gerald; Seemann, Rudolf; Fazekas, Andres; Ewers, Rolf; Piehslinger, Eva

2012-01-01

To determine patient satisfaction and preference for implant-supported mandibular overdentures (IOD) retained with ball or Locator attachments. In addition, peri-implant conditions and prosthodontic maintenance efforts for the final attachments were evaluated after 1 year of function. In this crossover clinical trial, 20 edentulous patients were recruited to receive two mandibular implants in the canine region and were provided with implant-retained mandibular overdentures and new complete maxillary dentures. Implant-retained mandibular overdentures were stabilized with either ball attachments or Locator attachments, in random order. After 3 months of function, the attachments in the existing denture were changed. Questionnaires on satisfaction/complaints with the prostheses were administered at baseline (with the old dentures) and after 3 months of function with each attachment, thus providing for an intraindividual comparison. The decision for the final attachment chosen was based on the patient's preference. For the definitive attachment, peri-implant conditions (peri-implant marginal bone resorption, pocket depth, and Plaque Index, Gingival Index, and Bleeding Index) as well as prosthodontic maintenance efforts and satisfaction score were evaluated after an insertion period of 1 year. Nineteen (95%) patients completed the study (1 dropout). Patient satisfaction improved significantly (P<.05) from baseline (old dentures) to the new prostheses retained with each of the two attachment types for all domains of satisfaction. However, there were no differences between ball or Locator attachment for any items of satisfaction evaluated and neither attachment had a significant patient preference. No differences for peri-implant parameters or for patient satisfaction were noted between the definitive attachments (ball, n=10; Locator, n=9) after 1 year. Although the overall incidence rate of prosthodontic maintenance did not significantly differ between both retention modalities, the Locator attachment required more postinsertion aftercare (activation of retention) than the ball anchors.
Reaction Event Counting Statistics of Biopolymer Reaction Systems with Dynamic Heterogeneity.

PubMed

Lim, Yu Rim; Park, Seong Jun; Park, Bo Jung; Cao, Jianshu; Silbey, Robert J; Sung, Jaeyoung

2012-04-10

We investigate the reaction event counting statistics (RECS) of an elementary biopolymer reaction in which the rate coefficient is dependent on states of the biopolymer and the surrounding environment and discover a universal kinetic phase transition in the RECS of the reaction system with dynamic heterogeneity. From an exact analysis for a general model of elementary biopolymer reactions, we find that the variance in the number of reaction events is dependent on the square of the mean number of the reaction events when the size of measurement time is small on the relaxation time scale of rate coefficient fluctuations, which does not conform to renewal statistics. On the other hand, when the size of the measurement time interval is much greater than the relaxation time of rate coefficient fluctuations, the variance becomes linearly proportional to the mean reaction number in accordance with renewal statistics. Gillespie's stochastic simulation method is generalized for the reaction system with a rate coefficient fluctuation. The simulation results confirm the correctness of the analytic results for the time dependent mean and variance of the reaction event number distribution. On the basis of the obtained results, we propose a method of quantitative analysis for the reaction event counting statistics of reaction systems with rate coefficient fluctuations, which enables one to extract information about the magnitude and the relaxation times of the fluctuating reaction rate coefficient, without a bias that can be introduced by assuming a particular kinetic model of conformational dynamics and the conformation dependent reactivity. An exact relationship is established between a higher moment of the reaction event number distribution and the multitime correlation of the reaction rate for the reaction system with a nonequilibrium initial state distribution as well as for the system with the equilibrium initial state distribution.
Electron Attachment to Halomethanes at High Temperature: CH2CI2, CF2CI2, CH3CI, and CF3CI Attachment Rate Constants up to 1100 K

DTIC Science & Technology

2009-08-01

hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and...attachment reactions: 390i 50 meV (CH:Cl;). 124* 20 meV (CF2CI2), 670 + 70 meV (CH3CI), and 406±50 meV (CF,C1). Comparisons are made with existing data ...Research Laboratory, 29 Randolph Road, Hanscom Air Force Base . Massachusetts 01731-3010, USA (Received 15 May 2009; accepted 4 August 2009; published
Early Attachment Organization with Both Parents and Future Behavior Problems: From Infancy to Middle Childhood

ERIC Educational Resources Information Center

Kochanska, Grazyna; Kim, Sanghag

2013-01-01

Links between children's attachment security with mothers and fathers, assessed in Strange Situation with each parent at 15 months ("N" = 101), and their future behavior problems were examined. Mothers and fathers rated children's behavior problems, and children reported their own behavior problems at age 8 ("N" = 86). Teachers…
The Role of Emotion in Parent-Child Relationships: Children's Emotionality, Maternal Meta-Emotion, and Children's Attachment Security

ERIC Educational Resources Information Center

Chen, Fu Mei; Lin, Hsiao Shih; Li, Chun Hao

2012-01-01

This study was intended to examine the relationship among children's emotionality, parental meta-emotion, and parent-child attachment. The sample consisted of 546 5th and 6th grade children and their mothers. The test instruments used in this study were the Emotionality subscale of the EAS Temperament Survey (mothers' ratings only), the Parental…
49 CFR 567.6 - Requirements for persons who do not alter certified vehicles or do so with readily attachable...

Code of Federal Regulations, 2010 CFR

2010-10-01

... manner that the vehicle's stated weight ratings are still valid, need not affix a label to the vehicle... certified vehicles or do so with readily attachable components. 567.6 Section 567.6 Transportation Other... OF TRANSPORTATION CERTIFICATION § 567.6 Requirements for persons who do not alter certified vehicles...
Social-Emotional Adjustment and Attachment in Children Adopted from China: Processes and Predictors of Change

ERIC Educational Resources Information Center

Cohen, Nancy J.; Farnia, Fataneh

2011-01-01

This study examined the processes and predictors of change in maternal ratings of internalizing and externalizing symptoms and attachment security in 70 infant girls adopted from China at a mean age of 13.5 months. These children's mental and language development were also directly assessed. The adopted children were assessed within the first…
The e[sup [minus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holroyd, R.A.; Schwarz, H.A.; Stradowska, E.

The rate constants for attachment of excess electrons to 1,3-butadiene (k[sub a]) and detachment from the butadiene anion (k[sub d]) in n-hexane are reported. The equilibrium constant, K[sub eq] = k[sub a]/k[sub d], increases rapidly with pressure and decreases as the temperature increases. At -7[degree]C attachment is observed at 1 bar. At high pressures the attachment rate is diffusion controlled. The activation energy for detachment is about 21 kcal/mol; detachment is facilitated by the large entropy of activation. The reaction volumes for attachment range from -181 cm[sup 3]/mol at 400 bar to-122 cm[sup 3]/mol at 1500 bar and are largelymore » attributed to the electrostriction volume of the butadiene anion ([Delta][bar V][sub el]). Values of [Delta][bar V][sub el] calculated by a model, which includes a glassy shell of solvent molecules around the ion, are in agreement with experimental reaction volumes. The analysis indicates the partial molar volume of the electron in hexane is small and probably negative. It is shown that the entropies of reaction are closely related to the partial molar volumes of reaction. 22 refs., 5 figs., 5 tabs.« less

Evaluation of evaporation coefficient for micro-droplets exposed to low pressure: A semi-analytical approach

NASA Astrophysics Data System (ADS)

Chakraborty, Prodyut R.; Hiremath, Kirankumar R.; Sharma, Manvendra

2017-02-01

Evaporation rate of water is strongly influenced by energy barrier due to molecular collision and heat transfer limitations. The evaporation coefficient, defined as the ratio of experimentally measured evaporation rate to that maximum possible theoretical limit, varies over a conflicting three orders of magnitude. In the present work, a semi-analytical transient heat diffusion model of droplet evaporation is developed considering the effect of change in droplet size due to evaporation from its surface, when the droplet is injected into vacuum. Negligible effect of droplet size reduction due to evaporation on cooling rate is found to be true. However, the evaporation coefficient is found to approach theoretical limit of unity, when the droplet radius is less than that of mean free path of vapor molecules on droplet surface contrary to the reported theoretical predictions. Evaporation coefficient was found to reduce rapidly when the droplet under consideration has a radius larger than the mean free path of evaporating molecules, confirming the molecular collision barrier to evaporation rate. The trend of change in evaporation coefficient with increasing droplet size predicted by the proposed model will facilitate obtaining functional relation of evaporation coefficient with droplet size, and can be used for benchmarking the interaction between multiple droplets during evaporation in vacuum.
Temperature Dependence of Dissociative Electron Attachment to Halogenated Hydrocarbons

NASA Astrophysics Data System (ADS)

Wang, Yicheng; Christophorou, Loucas G.

1996-10-01

Most of the gas mixtures currently in use for plasma processing of semiconductors involve halogenated hydrocarbons such as the strongly electronegative gases CCl4 and CFCl_3, the weakly electronegative gas CF_2Cl2 and the very weakly electronegative gases CHF3 and CF_4. Many dissociation processes are known to occur for these molecules. One of these dissociation reactions which is particularly effective for the strongly electronegative hydrocarbons is dissociative electron attachment. Even for weakly electron attaching gases, molecular dissociation via dissociative electron attachment at low energies can be an efficient dissociation process if the gas temperature is higher than ambient. Dissociative electron attachment is known to increase with increasing temperature above room temperature for many such compounds. In this paper, we report our measurements on the increases of the total electron attachment rate constant for CF_2Cl2 with increasing gas temperature from room temperature to about 600 K. -Research sponsored in part by the U.S. Air Force Wright Laboratory under contract F33615-96-C-2600 with the University of Tennessee. Also, Department of Physics, The University of Tennessee, Knoxville, TN.
Understanding the Pathways between Mothers' Childhood Maltreatment Experiences and Patterns of Insecure Attachment with Young Children via Symptoms of Depression.

PubMed

Khan, Maria; Renk, Kimberly

2018-05-11

Although research has suggested that mothers who experienced childhood maltreatment tend to exhibit heightened risk for attachment difficulties with their young children, less is known about the mechanisms underlying this association. Thus, this study examined mothers' symptoms of depression as a mediator in the relationship between mothers' childhood maltreatment experiences and patterns of insecure (i.e., anxious, avoidant, and disorganized) mother-young child attachment. Mothers (N = 146) with children aged 1½-to 5-years provided ratings of their childhood maltreatment experiences, attachment with their young children, and symptoms of depression. Mothers' symptoms of depression mediated significantly the relationship between mothers' childhood maltreatment experiences and patterns of insecure mother-young child attachment. These findings suggested that symptoms of depression in the context of mothers' childhood maltreatment may be related more directly to mother-young child attachment than childhood maltreatment experiences alone. These results demonstrated the importance of promoting trauma-informed parenting interventions for facilitating secure emotional connections between mothers and their young children.
Attachment linked predictors of women's emotional and cognitive responses to infant distress.

PubMed

Leerkes, Esther M; Siepak, Kathryn J

2006-03-01

The purpose of this study was to examine associations among women's emotional and cognitive responses to infant fear and anger and to identify attachment linked predictors of these responses. Four hundred and forty Caucasian and African American undergraduate college women viewed video clips of two crying infants, one displaying anger and the other displaying fear. They identified what the infants were feeling, made causal attributions about the cause of crying, rated their own emotional reactions to the crying infants, and reported on the extent to which their parents met their emotional needs in childhood and their current adult attachment patterns. Emotional and cognitive responses to infant fear and anger were interrelated. Consistent with prediction, a history of parental emotional rejection and adult attachment anxiety and avoidance correlated negatively with accurate identification of emotions and positively with negative attributions, amusement, and neutral responses to infant distress. Adult attachment security moderated the effects of early parental rejection on emotional and cognitive responses to infant distress, and these results varied based on race and parent gender. Results are discussed from an attachment theory perspective.
Nanostructured glass–ceramic coatings for orthopaedic applications

PubMed Central

Wang, Guocheng; Lu, Zufu; Liu, Xuanyong; Zhou, Xiaming; Ding, Chuanxian; Zreiqat, Hala

2011-01-01

Glass–ceramics have attracted much attention in the biomedical field, as they provide great possibilities to manipulate their properties by post-treatments, including strength, degradation rate and coefficient of thermal expansion. In this work, hardystonite (HT; Ca2ZnSi2O7) and sphene (SP; CaTiSiO5) glass–ceramic coatings with nanostructures were prepared by a plasma spray technique using conventional powders. The bonding strength and Vickers hardness for HT and SP coatings are higher than the reported values for plasma-sprayed hydroxyapatite coatings. Both types of coatings release bioactive calcium (Ca) and silicon (Si) ions into the surrounding environment. Mineralization test in cell-free culture medium showed that many mushroom-like Ca and phosphorus compounds formed on the HT coatings after 5 h, suggesting its high acellular mineralization ability. Primary human osteoblasts attach, spread and proliferate well on both types of coatings. Higher proliferation rate was observed on the HT coatings compared with the SP coatings and uncoated Ti-6Al-4V alloy, probably due to the zinc ions released from the HT coatings. Higher expression levels of Runx2, osteopontin and type I collagen were observed on both types of coatings compared with Ti-6Al-4V alloy, possibly due to the Ca and Si released from the coatings. Results of this study point to the potential use of HT and SP coatings for orthopaedic applications. PMID:21292725
Effects of Motility and Adsorption Rate Coefficient on Transport of Bacteria through Saturated Porous Media

PubMed Central

Camper, Anne K.; Hayes, Jason T.; Sturman, Paul J.; Jones, Warren L.; Cunningham, Alfred B.

1993-01-01

Three strains of Pseudomonas fluorescens with different motility rates and adsorption rate coefficients were injected into porous-medium reactors packed with l-mm-diameter glass spheres. Cell breakthrough, time to peak concentration, tailing, and cell recovery were measured at three interstitial pore velocities (higher than, lower than, and much lower than the maximal bacterial motility rate). All experiments were done with distilled water to reduce the effects of growth and chemotaxis. Contrary to expectations, motility did not result in either early breakthrough or early time to peak concentration at flow velocities below the motility rate. Bacterial size exclusion effects were shown to affect breakthrough curve shape at the very low flow velocity, but no such effect was seen at the higher flow velocity. The tendency of bacteria to adsorb to porous-medium surfaces, as measured by adsorption rate coefficients, profoundly influenced transport characteristics. Cell recoveries were shown to be correlated with the ratio of advective to adsorptive transport in the reactors. Adsorption rate coefficients were found to be better predictors of microbial transport phenomena than individual characteristics, such as size, motility, or porous-medium hydrodynamics. PMID:16349075
Applicability of Hydrologic Modeling to Tactical Military Decision Making

DTIC Science & Technology

1991-03-01

the continental United States. 111 DRAFT Table 4-4. Coefficient Ranges Location Range of Average Range of Average Ct Ct Cp Ct Appalachian 1.8-2.2 2.0... Mountainous --- 1.2 Watersheds Foothills --- 0.7 Areas Valley --- 0.4 Areas Eastern 0.4-1.0 0.8 0.5-1.0 0.8 Nebraska Corps of 0.4-8.0 0.3-0.9 --- Engineers...enemy to cover covert gorilla operations. b. Friendly Forces. Forces should be prepared to operate in a wet environment. c. Attachments and Detachments
Computer program for calculating supersonic flow on the windward side conical delta wings by the method of lines

NASA Technical Reports Server (NTRS)

Klunker, E. B.; South, J. C., Jr.; Davis, R. M.

1972-01-01

A user's manual is presented for a program that calculates the supersonic flow on the windward side of conical delta wings with shock attached at the sharp leading edge by the method of lines. The program also has a limited capability for computing the flow about circular and elliptic cones at incidence. It provides information including the shock shape, flow field, isentropic surface-flow properties, and force coefficients. A description of the program operation, a sample computation, and a FORTRAN 4 program listing are included.
High friction interactive aircraft tire-runway systems

NASA Technical Reports Server (NTRS)

Clark, S. K.

1974-01-01

The principle of utilizing geometric interaction between runway asperities and tire pattern design is discussed, and a theoretical basis is presented for substantial enhancement of frictional effects by this process. Test data confirming this is given. First order analytical expressions are given for the increased friction coefficients and for the engagement distances required. High speed friction data on a 7.00 x 8 aircraft tire is presented confirming this. Example design geometries are shown for the tire tread groove pattern, and designs and materials are discussed for the asperity grid and its attachment system.
Constraints of Melting, Sea-Level and the Paleoclimate from GRACE

NASA Technical Reports Server (NTRS)

Davis, James L.

2005-01-01

To gauge the accuracy of the GRACE data, we have undertaken a study to compare deformations predicted by GRACE inferences of seasonal water loading to crustal position variations determined from GRACE data. Two manuscripts that resulted from this study are attached. We found a very high correlation between the GRACE and GPS determinations for South America [Duvis et al., 2004]. We also developed a statistical approach for choosing which Stokes coefficients to include. This approach proves to be somewhat more accurate than the traditional Gaussian filter [Duvis et al., 2005].
Mechanism of poliovirus inactivation by ammonia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, R.L.

1978-05-01

Poliovirus inactivation by ammonia causes a slight reduction in the sedimentation coefficients of viral particles, but has no detectable effect on either the electrophoretic pattern of viral capsid proteins or the isoelectric points of inactivated particles. These virions still attach to cells, but are unable to repress host translation or stimulate the synthesis of detectable amounts of viral RNA. Although ammonia has no detectable effect on naked poliovirus RNA, it causes cleavage of this RNA when still within viral particles. Therefore, the RNA genome appears to be the only component of poliovirus significantly affected by ammonia.
Interdisciplinary study of atmospheric processes and constituents of the mid-Atlantic coastal region.. [air pollution control studies in Virginia

NASA Technical Reports Server (NTRS)

Kindle, E. C.; Bandy, E. C.; Copeland, G.; Blais, R.; Levy, G.; Sonenshine, D.

1975-01-01

Past research projects for the year 1974-1975 are listed along with future research programs in the area of air pollution control, remote sensor analysis of smoke plumes, the biosphere component, and field experiments. A detailed budget analysis is presented. Attachments are included on the following topics: mapping forest vegetation with ERTS-1 MSS data and automatic data processing techniques, and use of LARS system for the quantitative determination of smoke plume lateral diffusion coefficients from ERTS images of Virginia.
Results of investigations conducted in the LaRC 8-foot transonic pressure tunnel using the 0.010-scale 72-OTS model of the space shuttle integrated vehicle (IA93), volume 2

NASA Technical Reports Server (NTRS)

Nichols, M. E.

1976-01-01

Test procedures, history, and plotted coefficient data are presented for an aero-loads investigation on the updated configuration-5 space shuttle launch vehicle at Mach numbers from 0.600 to 1.205. Six-component vehicle forces and moments, base and sting-cavity pressures, elevon hinge moments, wing-root bending and torsion moments, and normal shear force data were obtained. Full simulation of updated vehicle protuberances and attach hardware was employed.
Infant Attachment Moderates Paths From Early Negativity to Preadolescent Outcomes for Children and Parents

PubMed Central

Boldt, Lea J.; Kochanska, Grazyna; Jonas, Katherine

2016-01-01

Although infant attachment has been long seen as key for development, its long-term effects may be complex. Attachment may be a catalyst or moderator of future developmental sequelae rather than a source of main effects. In 102 mothers, fathers, and infants, attachment was assessed at 15 months, children’s negativity (rejection of parental rules and modeling attempts) at 25, 38, 52, and 67 months, and developmental outcomes (the child’s parent-rated externalizing problems and the parent-child observed relationship quality) at ages 10 and 12. In both mother- and father-child relationships, children’s higher negativity was associated with more detrimental outcomes, but only in dyads with formerly insecure infants. Infant insecurity appears to amplify detrimental cascades, whereas infant security appears to defuse such risks. PMID:27569427
Hormonal regulation of growth and life span of bullfrog tadpole tail epidermal cells cultured in vitro.

PubMed

Nishikawa, A; Yoshizato, K

1986-02-01

Epidermal cells were dissociated from tails of the bullfrog tadpole, Rana catesbeiana, and cultured to investigate their response to steroid and thyroid hormones. Charcoal-treated serum (CTS) was used in the growth medium when cells were to be grown in the absence of steroid and thyroid hormones. The cells could be maintained for 2 weeks with a small increase in cell number in medium that contained CTS (CTS medium). Addition of cortisol to CTS medium increased both cellular attachment to the culture dishes and the proliferation of the attached cells with an optimum concentration of 5 X 10(-7) M. The cells remained viable and attached for at least a week. Cortisol stimulated the rate of protein synthesis 1.8-fold but did not alter the rate of DNA synthesis. The cells did not proliferate in the medium containing triiodothyronine (T3) and detached themselves from the dish within 5 days, which occurred in a dose-dependent manner with a maximum effect at 10(-8) M. It drastically decreased the rate of DNA synthesis but did not influence the rate of protein synthesis. These responses of cells to cortisol and T3 may reflect growth and death of tail epidermal cells in vivo at metamorphosis.
How to harvest solar energy with the photosynthetic reaction center

NASA Astrophysics Data System (ADS)

Balaeff, Alexander; Reyes, Justin

Photosynthetic reaction center (PRC) is a protein complex that performs a key step in photosynthesis: the electron-hole separation driven by photon absorbtion. The PRC has a great promise for applications in solar energy harvesting and photosensing. Such applications, however, are hampered by the difficulty in extracting the photogenerated electric charge from the PRC. To that end, it was proposed to attach the PRC to a molecular wire through which the charge could be collected. In order to find the attachment point for the wire that would maximize the rate of charge outflow from the PRC, we performed a computational study of the PRC from the R. virdis bacterium. An ensemble of PRC structures generated by a molecular dynamics simulation was used to calculate the rate of charge transport from the site of initial charge separation to several trial sites on the protein surface. The Pathways model was used to calculate the charge transfer rate in each step of the network of heme co-factors through which the charge transport was presumed to proceed. A simple kinetic model was then used to determine the overall rate of the multistep charge transport. The calculations revealed several candidate sites for the molecular wire attachment, recommended for experimental verification.
Channel specific rate constants for reactions of O(1D) with HCl and HBr

NASA Technical Reports Server (NTRS)

Wine, P. H.; Wells, J. R.; Ravishankara, A. R.

1986-01-01

The absolute rate coefficients and product yields for reactions of O(1D) with HCl(1) and HBr(2) at 287 K are presently determined by means of the time-resolved resonance fluorescence detection of O(3P) and H(2S) in conjunction with pulsed laser photolysis of O3/HX/He mixtures. Total rate coefficients for O(1D) removal are found to be, in units of 10 to the -10th cu cm/molecule per sec, k(1) = 1.50 + or - 0.18 and k(2) 1.48 + or - 0.16; the absolute accuracy of these rate coefficients is estimated to be + or - 20 percent.
A review of reaction rates in high temperature air

NASA Technical Reports Server (NTRS)

Park, Chul

1989-01-01

The existing experimental data on the rate coefficients for the chemical reactions in nonequilibrium high temperature air are reviewed and collated, and a selected set of such values is recommended for use in hypersonic flow calculations. For the reactions of neutral species, the recommended values are chosen from the experimental data that existed mostly prior to 1970, and are slightly different from those used previously. For the reactions involving ions, the recommended rate coefficients are newly chosen from the experimental data obtained more recently. The reacting environment is assumed to lack thermal equilibrium, and the rate coefficients are expressed as a function of the controlling temperature, incorporating the recent multitemperature reaction concept.
Very preterm/very low birthweight infants' attachment: infant and maternal characteristics.

PubMed

Wolke, Dieter; Eryigit-Madzwamuse, Suna; Gutbrod, Tina

2014-01-01

To investigate whether there are differences in attachment security and disorganisation between very preterm or very low birthweight (VP/VLBW) (<32 weeks gestation or <1500 g birthweight) and full-term infants (37-42 weeks gestation) and whether the pathways to disorganised attachment differ between VP/VLBW and full-term infants. The sample with complete longitudinal data consisted of 71 VP/VLBW and 105 full-term children and their mothers matched for twin status, maternal age, income and maternal education. Infant attachment was assessed with the Strange Situation Assessment at 18 months of age. Maternal sensitivity in the VP/VLBW and full-term samples was rated by neonatal nurses and community midwives in the neonatal period, respectively, and mother-infant interaction was observed at 3 months. Infant difficultness was assessed by maternal report at 3 months and infant's developmental status was assessed with the Bayley Scales (BSID-II). Most VP/VLBW (61%) and full-term (72%) children were found to be securely attached. However, more VP/VLBW (32%) than full-term children (17%) had disorganised attachment. Longitudinal path analysis found that maternal sensitivity was predictive of attachment disorganisation in full-term children. In contrast, infant's distressing cry and infant's developmental delay, but not maternal sensitivity, were predictive of disorganised attachment in VP/VLBW children. A third of VP/VLBW children showed disorganised attachment. Underlying neurodevelopmental problems associated with VP/VLBW birth appear to be a common pathway to a range of social relationship problems in this group. Clinicians should be aware that disorganised attachment and relationship problems in VP/VLBW infants are frequent despite sensitive parenting.
Breastfeeding, Parenting, and Infant Attachment Behaviors.

PubMed

Gibbs, Benjamin G; Forste, Renata; Lybbert, Emily

2018-04-01

Objectives Infants and toddlers need secure attachments in order to develop the social competence required to successfully navigate later peer and adult relationships. Breastfeeding is a parenting factor that has been associated with child emotional development-specifically the attachment between children and their mothers. Yet, this link may simply be the result of other parenting behaviors that are associated with breastfeeding. Thus, our objective is to examine whether the link between infant attachment behaviors and breastfeeding endures when accounting for a broad array of in-depth measures of parenting. Methods We use the Early Childhood Longitudinal Study of children from 9 months to 2 years of age collected by the National Center for Education Statistics. Using Ordinary Least Squares regression, data analyses examine the association between the Toddler Attachment Sort-45 (TAS-45) measures of toddler-parent attachment (infant attachment security and temperamental dependency) and breastfeeding practices. We also examine individual items of the TAS-45 to isolate specific attachment behaviors that have the strongest associations with breastfeeding. Results We find an enduring link between children who are predominantly breastfed for six or more months and infant attachment security. However, we find no evidence that breastfeeding is linked to a child's temperamental dependency. Of the nine items used to examine infant attachment behaviors, we find that breastfed children are rated as having slightly higher scores on two measures ("warm and cuddly," "cooperative") and lower scores on one measure ("demanding/angry"). Conclusions for Practice Breastfeeding has an important link to the child's use of their caregiver as a secure base for exploration and a place of comfort when distressed (infant attachment security). Yet, breastfeeding does not appear to reduce a child's temperamental dependency or level of clinginess as measured by how demanding, fussy or distressed the child becomes when separated.

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