COOP Charts in French: translation and preliminary data on instrument properties

This paper describes the procedure used to translate the COOP Charts into French and provides preliminary information on the instrument's acceptability, reliability and validity. The charts were translated in several steps: seven initial translations were combined into a first pilot version, which was then tested for acceptability, clarity and alternate wordings in two convenience samples taken from the general population (n=53). The modified version was then reviewed by a lay panel and another translator and submitted by mail to 209 congress participants to test several construct validity hypotheses through known-groups comparisons. A panel of public health professionals discussed the content validity of the charts. Finally, test-retest reliability and concurrent validity with SF-36 Health Survey scores were examined among 65 patients with end-stage renal disease. The translation process identified a wide variability in translation options for several items. The acceptability of the charts was excellent. The test-retest correlations ranged from 0.60 to 0.87. Content validity appeared to be appropriate, except for the chart on ‘social support', which combines the questions of need and availability of social support. The utility of illustrations was questioned by some respondents: many claimed not to have used the illustrations in selecting their response, while others found them to be not expressive enough. Most preliminary tests of construct validity were consistent with theory. This French translation of the COOP Charts appears to be ready for more extensive testing in the intended target population of ambulatory patient

Correlated electron metal properties of the honeycomb ruthenate Na₂RuO₃

We report the synthesis and characterization of polycrystalline Na_{2}RuO_{3}, a layered material in which the Ru^{4+} (4d^{4} configuration) form a honeycomb lattice. The optimal synthesis condition was found to produce a nearly ordered Na_{2}RuO_{3} (C2/c phase), as assessed from the refinement of the time-of-flight neutron powder diffraction. Magnetic susceptibility measurements reveal a large temperature-independent Pauli paramagnetism [x_{0} ~ 1.42(2) x 10^{-3} emu/mol Oe] with no evidence of magnetic ordering down to 1.5 K, and with an absence of dynamic magnetic correlations, as evidenced by neutron scattering spectroscopy. The intrinsic susceptibility (x_{0}) together with the Sommerfeld coefficient of gamma = 11.7(2) mJ/Ru mol K^{2} estimated from heat capacity measurements gives an enhanced Wilson ratio of R_{w} ≈ 8.9(1), suggesting that magnetic correlations may be present in this material. While transport measurements on pressed pellets show nonmetallic behavior, photoemission spectroscopy indicates a small but finite density of states at the Fermi energy, suggesting that the bulk material is metallic. Except for resistivity measurements, which may have been compromised by near-surface and interface effects, all other probes indicate that Na_{2}RuO_{3} is a moderately correlated electron metal. Our results thus stand in contrast to earlier reports that Na_{2}RuO_{3} is an antiferromagnetic insulator at low temperatures

Correlated electron metal properties of the honeycomb ruthenate Na2_2RuO3_3

We report the synthesis and characterisation of polycrystalline Na$_2$RuO$_3$, a layered material in which the Ru$^{4+}$ ($4d^4$ configuration) form a honeycomb lattice. The optimal synthesis condition was found to produce a nearly ordered Na$_2$RuO$_3$ ($C2/c$ phase), as assessed from the refinement of the time-of-flight neutron powder diffraction. Magnetic susceptibility measurements reveal a large temperature-independent Pauli paramagnetism ($\chi_0 \sim 1.42(2)\times10^{-3}$ emu/mol Oe) with no evidence of magnetic ordering down to 1.5 K, and with an absence of dynamic magnetic correlations, as evidenced by neutron scattering spectroscopy. The intrinsic susceptibility ($\chi_0$) together with the Sommerfeld coeficient of $\gamma=11.7(2)$ mJ/Ru mol K$^2$ estimated from heat capacity measurements, gives an enhanced Wilson ratio of $R_W\approx8.9(1)$, suggesting that magnetic correlations may be present in this material. While transport measurements on pressed pellets show nonmetallic behaviour, photoemission spectrocopy indicate a small but finite density of states at the Fermi energy, suggesting that the bulk material is metallic. Except for resistivity measurements, which may have been compromised by near surface and interface effects, all other probes indicate that Na$_2$RuO$_3$ is a moderately correlated electron metal. Our results thus stand in contrast to earlier reports that Na$_2$RuO$_3$ is an antiferromagnetic insulator at low temperatures.Comment: 9 pages, 6 figure

3D acoustic propagation through an estuarine salt wedge at low-to-mid-frequencies: Modeling and measurement

Author Posting. © Acoustical Society of America, 2019. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 146(3),(2019): 1888-1902, doi:10.1121/1.5125258.The estuarine salt wedge presents a dynamic and highly refractive waveguide, the acoustic propagation characteristics of which are controlled by the water column sound speed gradient and boundary interactions. Acoustically, the salt wedge consists of two isospeed layers separated by a thin, three-dimensional (3D), high-gradient layer. The behavior of a broadband (500–2000 Hz) acoustic field under the influence of an estuarine salt wedge in the Columbia River estuary is explored using two 3D acoustic propagation models: 3D rays and 3D parabolic equation. These model results are compared to data collected during the field experiment. Results demonstrate that the dominant physical mechanism controlling acoustic propagation in this waveguide shifts from 3D bottom scatter in a non-refractive waveguide (before the entrance of the salt wedge) to 3D acoustic refraction with minimal bottom interaction in a refractive waveguide (when the salt wedge occupies the acoustic transect). Vertical and horizontal refraction in the water column and out-of-plane scattering by the bottom are clearly evident at specific narrowband frequencies; however, these mechanisms contribute to, but do not account for, the total observed broadband transmission loss.Environmental input to the acoustic models included high resolution bathymetric survey data provided by Guy Gelfenbaum (USGS), and modeled temperature and salinity profiles of the water column provided by Antonio Baptista, Charles Seaton, and Paul Turner at CMOP. The authors thank Derek Olson (NPS) for invaluable assistance with running the 3DPE model on NPS HPC resources. This work was supported by the Office of Naval Research.2020-03-3

Optimizing Sales Using Mobile Sales Ticketing Application

A pressure-induced collapse of magnetic ordering in $β−Li_{2}IrO_3$ at $P_m ∼ 1.5–2$ GPa has previously been interpreted as evidence for possible emergence of spin liquid states in this hyperhoneycomb iridate, raising prospects for experimental realizations of the Kitaev model. Based on structural data obtained at room temperature, this magnetic transition is believed to originate in small lattice perturbations that preserve crystal symmetry, and related changes in bond-directional anisotropic exchange interactions. Here we report on the evolution of the crystal structure of $β−Li_{2}IrO_3$ under pressure at low temperatures $(T≤50 K)$ and show that the suppression of magnetism coincides with a change in lattice symmetry involving Ir-Ir dimerization. The critical pressure for dimerization shifts from 4.4(2) GPa at room temperature to $∼1.5–2$ GPa below 50 K. While a direct $Fddd→C2/c$ transition is observed at room temperature, the low temperature transitions involve new as well as coexisting dimerized phases. Further investigation of the Ir ($L3/L_2$) isotropic branching ratio in x-ray absorption spectra indicates that the previously reported departure of the electronic ground state from a $J_{eff} = 1/2$ state is closely related to the onset of dimerized phases. In essence, our results suggest that the predominant mechanism driving the collapse of magnetism in $β−Li_{2}IrO_3$ is the pressure-induced formation of $Ir_2$ dimers in the hyperhoneycomb network. The results further confirm the instability of the $J_{eff} = 1/2$ moments and related noncollinear spiral magnetic ordering against formation of dimers in the low-temperature phase of compressed $β−Li_{2}IrO_3$

Kinetic alteration of the 6Mg(NH2)2-9LiH-LiBH4 system by co-adding YCl3 and Li3N

The 6Mg(NH2)2-9LiH-LiBH4 composite system has a maximum reversible hydrogen content of 4.2 wt% and a predicted dehydrogenation temperature of about 64 °C at 1 bar of H2. However, the existence of severe kinetic barriers precludes the occurrence of de/re-hydrogenation processes at such a low temperature (H. Cao, G. Wu, Y. Zhang, Z. Xiong, J. Qiu and P. Chen, J. Mater. Chem. A, 2014, 2, 15816-15822). In this work, Li3N and YCl3 have been chosen as co-additives for this system. These additives increase the hydrogen storage capacity and hasten the de/re-hydrogenation kinetics: a hydrogen uptake of 4.2 wt% of H2 was achieved in only 8 min under isothermal conditions at 180 °C and 85 bar of H2 pressure. The re-hydrogenation temperature, necessary for a complete absorption process, can be lowered below 90 °C by increasing the H2 pressure above 185 bar. Moreover, the results indicate that the hydrogenation capacity and absorption kinetics can be maintained roughly constant over several cycles. Low operating temperatures, together with fast absorption kinetics and good reversibility, make this system a promising on-board hydrogen storage material. The reasons for the improved de/re-hydrogenation properties are thoroughly investigated and discussed

Processing of aluminum-graphite particulate metal matrix composites by advanced shear technology

Copyright @ 2009 ASM International. This paper was published in Journal of Materials Engineering and Performance 18(9) and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.To extend the possibilities of using aluminum/graphite composites as structural materials, a novel process is developed. The conventional methods often produce agglomerated structures exhibiting lower strength and ductility. To overcome the cohesive force of the agglomerates, a melt conditioned high-pressure die casting (MC-HPDC) process innovatively adapts the well-established, high-shear dispersive mixing action of a twin screw mechanism. The distribution of particles and properties of composites are quantitatively evaluated. The adopted rheo process significantly improved the distribution of the reinforcement in the matrix with a strong interfacial bond between the two. A good combination of improved ultimate tensile strength (UTS) and tensile elongation (e) is obtained compared with composites produced by conventional processes.EPSR

Are non-responders in a quitline evaluation more likely to be smokers?

BACKGROUND: In evaluation of smoking cessation programs including surveys and clinical trials the tradition has been to treat non-responders as smokers. The aim of this paper is to assess smoking behaviour of non-responders in an evaluation of the Swedish national tobacco cessation quitline a nation-wide, free of charge service. METHODS: A telephone interview survey with a sample of people not participating in the original follow-up. The study population comprised callers to the Swedish quitline who had consented to participate in a 12 month follow-up but had failed to respond. A sample of 84 (18% of all non-responders) was included. The main outcome measures were self-reported smoking behaviour at the time of the interview and at the time of the routine follow-up. Also, reasons for not responding to the original follow-up questionnaire were assessed. For statistical comparison between groups we used Fischer's exact test, odds ratios (OR) and 95% confidence intervals (CI) on proportions and OR. RESULTS: Thirty-nine percent reported to have been smoke-free at the time they received the original questionnaire compared with 31% of responders in the original study population. The two most common reasons stated for not having returned the original questionnaire was claiming that they had returned it (35%) and that they had not received the questionnaire (20%). Non-responders were somewhat younger and were to a higher degree smoke-free when they first called the quitline. CONCLUSION: Treating non-responders as smokers in smoking cessation research may underestimate the true effect of cessation treatment