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How does single-party dominance influence interpersonal trust? We draw on evidence from trust games played by more than 2,000 subjects in South Africa, where, since Apartheid, race-based social enmity has persisted under democratic competition characterized by single-party dominance. We find that partisan-based trust discrimination is most pronounced for those who identify with the main opposition party and is driven by strong distrust of rival partisans. These findings underscore how electoral competition, in general, shapes trust across party lines and suggests one-sided competition, in particular, has asymmetrical effects between parties in dominant party systems. Moreover, this study provides additional evidence regarding the relative weights of trustworthiness stereotypes tied to partisanship and race.
We study stimulated generation – the transfer of energy from balanced flows to existing internal waves – using an asymptotic model that couples barotropic quasi-geostrophic flow and near-inertial waves with
vertical structure, where
is the vertical wavenumber and
is the vertical coordinate. A detailed description of the conservation laws of this vertical-plane-wave model illuminates the mechanism of stimulated generation associated with vertical vorticity and lateral strain. There are two sources of wave potential energy, and corresponding sinks of balanced kinetic energy: the refractive convergence of wave action density into anti-cyclones (and divergence from cyclones); and the enhancement of wave-field gradients by geostrophic straining. We quantify these energy transfers and describe the phenomenology of stimulated generation using numerical solutions of an initially uniform inertial oscillation interacting with mature freely evolving two-dimensional turbulence. In all solutions, stimulated generation co-exists with a transfer of balanced kinetic energy to large scales via vortex merging. Also, geostrophic straining accounts for most of the generation of wave potential energy, representing a sink of 10 %–20 % of the initial balanced kinetic energy. However, refraction is fundamental because it creates the initial eddy-scale lateral gradients in the near-inertial field that are then enhanced by advection. In these quasi-inviscid solutions, wave dispersion is the only mechanism that upsets stimulated generation: with a barotropic balanced flow, lateral straining enhances the wave group velocity, so that waves accelerate and rapidly escape from straining regions. This wave escape prevents wave energy from cascading to dissipative scales.
The standard engine behind core-collapse supernovae is continuously evolving with increasingly detailed models. At this time, most simulations focus on an engine invoking turbulence above the proto-neutron star, sometimes termed the “convection-enhanced” engine. Here we review this engine and why it has become the standard for normal supernovae, focusing on a wide set of observations that provide insight into the supernova engine.
It has been proposed that perceived control plays an important role in influencing health-related behaviour. This study examined the relationship between locus of control and the return-to-work achievements of a group of back-injured workers' compensation claimants. The obtained results supported the hypothesised relationships between both ‘internal’ and ‘powerful others’ locus of control, and the return-to-work criterion variables. It was concluded that use of rehabilitation-specific measures of locus of control (such as were employed in the present study) could guide the program planning efforts of rehabilitation personnel dealing with this client group.
This paper reports the results from a qualitative study aimed at identifying the factors influencing the rehabilitation experience of people living with an amputation in a rural setting. Following the conduct of an initial focus group, 24 rural-based individuals responded to an invitation to participate in the study's in-depth interviews. Fourteen of those interviewed lived in a ‘regional’ setting (the regional group) and the other ten lived in more remote locations (the ‘distant’ group). Consistent with this population's demography, the sample was comprised mainly of older people (mean age of 66.8 years) who had suffered their amputation as a result of vascular disease. While the groups differed with respect to two aspects of their rehabilitation experience (with the distant group reporting more problems with accommodation and access to health services), many common themes emerged from the interviews, including an overall positive acceptance of the surgical intervention, the call for increased post-operative counselling services, and an endorsement of the usefulness of peer-support (and more generally of social support) services. Results are discussed in terms of their implications for service delivery and endorsement is made of the suggestion that rural health planning be more community-focussed.
Cobalt nanoparticles were synthesized by means of a hot metal reduction reaction with cobalt chloride as precursor material. The size of cobalt nanoparticles was controlled by the choice of surfactant and the molar ratio of surfactant-to-reagent. Surfactants with larger alkane side chains yielded a smaller average nanoparticle size (diameter) and tighter size distribution, as these chains provided steric hindrance to the growth of the nanoparticles after initial nucleation. For each alkane side chain, a high molar ratio of surfactant-to-reagent (HSR) rendered nanoparticles with smaller particle size, while a low molar ratio of surfactant-to-reagent (LSR) produced larger nanoparticles. Measurements on transmission electron microscope images of cobalt particles synthesized with tri-octylphosphine revealed an average particle size of 6.9 nm (HSR) and 9.1 nm (LSR), while particles synthesized with tri-butylphosphine had a mean diameter of 12.5 nm (HSR) and 14.9 nm (LSR). X-ray diffraction profiles indicated that particles had metastable ε-cobalt structure. Room temperature magnetization measurements showed ferromagnetic behavior with highly square M-H loops indicative of single domain particles with coercive fields in the range of 400–500 Oe.
Polarized radiation is used in a Fourier transform infrared (FTIR) microspectroscopic technique to detect molecular conformational change in collagen fibers resulting from deterioration. Absorbance spectra of single fibers are produced with polarization oriented first parallel (A‖) and then perpendicular (A⊥) to the fiber axis. The amide Ill band (1230- 1300 cm−1) shows strong positive dichroism, with up to six times greater absorbance occurring with parallel polarization. Losses of dichroism result from breakdown in the molecular structure of collagen. Integrations of the amide III bands are used in ratios, A‖/A⊥;, which provide a measure of the degree of molecular order. Ratios for degraded and undegraded material are compared to produce semi-quantitative information about deterioration.
We have extended our previous investigation of the electrical characteristics of a Pd/AlN/Si thin film sensor for varying thicknesses of AlN, from 300–2000Å. The capacitance vs. voltage, C(V), and conductance vs. voltage, G(V), measurements were utilized to investigate the presence of surface states within the Si gap at the AlN/Si interface. Our previous experiments on 500Å AlN did show the presence of interface traps, with an estimated surface density between 8×1014 and 1.5×1015 m−2eV−1 . In our present work we've examined the effect of AlN thickness on the density of these interface traps. The density is dependent on AlN thickness. The thinner devices, 300Å, showed an interface trap density of 20–30×1015 m−2eV−1. The interface trap density decreased with increasing thickness up to 500Å, where the density remained relatively constant at about 1–5×1015 m−2eV−1 for thicknesses up to 2000Å. We have also shown that the interface trap density is independent of annealing.
Cementitious reactions and ettringite formation, which occur when water is added to high-calcium fly ash, to many dry flue gas desulfurization solids, and to two of the residues from the emerging “clean coal” technologies, fluidized bed combustion and limestone injection multiphase burner, have been studied. The parameters varied included water to solid ratio and curing time. Crystalline reactants and products were monitored by X-ray powder diffraction. The amount of ettringite, the principal crystalline cementitious reaction product, was determined after three months of curing. Results are discussed in terms of available Ca, Al and S in each by-product and w/s ratio.
The database of chemical, mineralogical and physical characteristics of North American Fly ashes, assembled by the WFARDDC in North Dakota, was analyzed using multivariate statistics. Prior to the multivariate analysis, the data were rearranged in subgroups containing information on bulk-chemistry, glass chemistry, mineralogy and ASTM physical test results. These groups were analyzed individually. The multivariate technique used was Fuzzy C-Means Cluster Analysis, combined with Non-Linear Mapping. Analysis of the data-set indicates a relation between glass network former and network modifier content. The database shows that a subdivision on the basis of bulk CaO (< 11%; 11–20%; >20%) correlates well with the ASTM C618 Σ(SiO2 +Al2O3 +Fe2O3) and/or specific gravity. Mineralogical data indicate a subdivision into clusters containing varying amounts of mullite, quartz and/or ferrite spinel and a variety of Ca-containing minerals; high CaO ashes usually have high Ca-mineral contents. Of the CaO containing minerals, only portlandite contributed slightly to the compressive strength as defined by ASTM C618. Analysis of glass chemistry reveals smaller differences in absolute amounts of major oxides than would be expected on the basis of bulk chemistry alone. Surprisingly, the total glass content does not contribute significantly to 28 day compressive strength; multiple regression analysis only indicates a significant relation of particle size and specific gravity with the ASTM Pozzolanic Activity Index (portland cement). The Pozzolanic Activity Index with lime seems to be of limited importance in evaluating the performance of fly ashes as mineral admixtures in concrete. On the basis of the statistical analysis, suggestions for selection of important classifying variables are made.
Recent results on synthesis, crystal chemistry, structure and stability of ettringite*, with specific reference to use of this material in hazardous waste immobilization, are presented. Ettringites with selenate, chromate, borate, sulfite and carbonate replacing sulfate have been synthesized and characterized by XRD for phase purity and structure. In X-ray powder diffractograms, selenate and chromate etringites have the normal trigonal P31cettringite structure, whereas the borate, sulfite and carbonate ettringites can be indexed on a hexagonal unit cell with a halved c parameter. In excess of 95% of the Se and B in solutions spiked with various concentrations of these elements has been removed by precipitation of ettringite. Ettringites appear to be unstable in solutions outside of the approximate pH range 11.0-12.5, and there is a potential for some oxyanion exchange between ettringites and oxyanion-containing solutions. Buffering of pH, and dissolved Ca, Al and sulfate activities by other components of ettringite-based hazardous waste forms, combined with low-reactivity C-S-H matrices, could largely mitigate these concerns.
Thin ruthenium films were deposited using chemical vapor deposition from the single-source precursor tricarbonyl(1,3-cyclohexadiene)Ru(0) onto silicon, silicon dioxide and c-plane sapphire substrates in the absence of a carrier gas by thermolysis. Growth rate, resistivity, purity, crystallinity and microstructure were determined. Tricarbonyl(1,3-cyclohexadiene)Ru(0) gave metallic ruthenium films with near bulk resistivities (11-21μΩ-cm), high growth rates (up to 20 nm/min), and nearly featureless microstructures. Nucleation was rapid on all substrates tested. These results suggest that tricarbonyl(1,3-cyclohexadiene)Ru(0) is an excellent, practical precursor to use for practical applications that require depositing thin ruthenium films.
This paper presents an overview of the development of novel disposable smart plastic fluidic biochips for clinical diagnostic applications. The biochip is manufactured using a low-cost, rapid turn around injection molding/embossing process on a plastic substrate. The plastic fluidic biochip uses a novel sPROMs (structurally programmable microfluidic system) approach to achieve passive control of fluidic sequencing [1-2]. The plastic biochip also uses an on-chip pressurized air source for fluidic movement thus eliminating the need for active driving mechanisms and allowing for a truly disposable approach. Furthermore, electrochemical biosensors are also integrated on-chip to analyze various metabolically significant parameters such as PO2(partial pressure of oxygen), Glucose, Lactate,and pH. The fluidic biochip is being developed for point-of-care health monitoring applications where parameters such as small size, simplicity of operation, disposability, reduced cross-contamination are vital. The issues mentioned above are successfully addressed using the approach of this work and are discussed in this paper.
The biological membranes of Trypanosoma brucei contain a complex array of phospholipids that are synthesized de novo from precursors obtained either directly from the host, or as catabolised endocytosed lipids. This paper describes the use of nanoflow electrospray tandem mass spectrometry and high resolution mass spectrometry in both positive and negative ion modes, allowing the identification of ~500 individual molecular phospholipids species from total lipid extracts of cultured bloodstream and procyclic form T. brucei. Various molecular species of all of the major subclasses of glycerophospholipids were identified including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol as well as phosphatidic acid, phosphatidylglycerol and cardolipin, and the sphingolipids sphingomyelin, inositol phosphoceramide and ethanolamine phosphoceramide. The lipidomic data obtained in this study will aid future biochemical phenotyping of either genetically or chemically manipulated commonly used bloodstream and procyclic strains of Trypanosoma brucei. Hopefully this will allow a greater understanding of the bizarre world of lipids in this important human pathogen.
This study was designed to examine the nature of object imitation performance in early autism. We hypothesized that imitation would be relatively preserved when behaviors on objects resulted in salient instrumental effects. We designed tasks in which, in one condition, the motor action resulted in a salient, meaningful effect on an object, whereas in the other condition, the same action resulted in a less salient effect because of differing object characteristics. The motor aspects of the tasks did not vary across conditions. Four participant groups of 2- to 5-year-olds were examined: 17 children with early-onset autism, 24 children with regressive onset autism, 22 children with developmental delays, and 22 children with typical development. Groups were matched on nonverbal skills, and differences in verbal development were examined as a moderator of imitative ability. Results revealed an interaction of group by condition, with the combined autism group failing more tasks than the combined comparison groups, and failing more tasks in the less salient condition than in the more salient condition, as hypothesized. Analyses of autism subgroups revealed these effects were primarily because of the regression onset group. Accuracy of motor performance was examined by analyzing errors. Among children passing imitative acts, there were no group differences and no condition effects in the number, type, or pattern of performance errors. Among children passing the tasks, the group with autism did not demonstrate more emulation errors (imitating the goal but not the means) than other groups. There was no evidence that either motor or attentional aspects of the tasks contributed to the poorer imitative performance of the children with autism.