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Empowering Expression for Users with Aphasia through Constrained Creativity
Creative activities allow people to express themselves in rich, nuanced ways. However, being creative does not always come easily. For example, people with speech and language impairments, such as aphasia, face challenges in creative activities that involve language. In this paper, we explore the concept of constrained creativity as a way of addressing this challenge and enabling creative writing. We report an app, MakeWrite, that supports the constrained creation of digital texts through automated redaction. The app was co-designed with and for people with aphasia and was subsequently explored in a workshop with a group of people with aphasia. Participants were not only successful in crafting novel language, but, importantly, self-reported that the app was crucial in enabling them to do so. We refect on the potential of technology-supported constrained creativity as a means of empowering expression amongst users with diverse needs
Light Element X-Ray Microanalysis in Biology
It is shown that both qualitative and quantitative light element X-ray microanalysis of biological samples is feasible. These analyses were carried out using ultrathin window (UTW) detectors. Quantitative analysis yields a total element analysis with H estimated by difference or guesstimated . Comparison with calculated concentrations, or concentrations obtained by chemical analysis, shows that X-ray microanalysis of sections, by the peak to continuum ratio model, give sufficiently accurate results for biological purposes.
The measurement of O concentrations to yield water content is carried out using x-ray imaging techniques, so that the distribution of heavier elements can be spatially related to water and dry mass distribution. Similarly light element and heavy/light element ratios are readily visualised by X-ray imaging. These ratios can indicate the subcellular distribution of different molecular species e.g., nitrogenous compounds such as urates. It is possible to derive quantitative images of water distribution in both sections and bulk samples. Comparisons of the same sample type both as frozen sections and frozen bulk samples show that the water estimates obtained by the two different analytical methods are similar.
Oxygen analysis of C films at different specimen temperatures unequivocally reveals the temperature at which ice deposition on the specimen commences. This establishes safe conditions for reducing mass loss in model samples and freeze-dried sections to minimal levels and for avoiding artefactual oxygen analyses of both frozen-hydrated and freeze-dried sections
Iridium-coated rhenium thrusters by CVD
Operation of spacecraft thrusters at increased temperature reduces propellant requirements. Inasmuch as propellant comprises the bulk of a satellite's mass, even a small percentage reduction makes possible a significant enhancement of the mission in terms of increased payload. Because of its excellent high temperature strength, rhenium is often the structural material of choice. It can be fabricated into free-standing shapes by chemical vapor deposition (CVD) onto an expendable mandrel. What rhenium lacks is oxidation resistance, but this can be provided by a coating of iridium, also by CVD. This paper describes the process used by Ultramet to fabricate 22-N (5-lbf) and, more recently, 445-N (100-lbf) Ir/Re thrusters; characterizes the CVD-deposited materials; and summarizes the materials effects of firing these thrusters. Optimal propellant mixture ratios can be employed because the materials withstand an oxidizing environment up to the meltimg temperature of iridium, 2400 C (4350 F)
Assessing Input Brand Loyalty among U.S. Agricultural Producers
This study explores the prevalence and determinants of brand loyalty for agricultural input products. Results suggest that loyalty for both expendable and capital inputs is high among commercial agricultural producers in the United States. Producer attitudes, beliefs, and some demographic characteristics are useful identifiers of brand loyalty among commercial producers.brand loyalty, dealer loyalty, capital inputs, expendable inputs, farmer purchase decisions, Agricultural Finance, Consumer/Household Economics, Marketing, Q10, Q13, Q14,
Assessing Agricultural Input Brand Loyalty Among U.S. Mid-Size and Commercial Producers
This study explores the prevalence and determinants of brand loyalty for agricultural input products. Results suggest that loyalty for both expendable and capital inputs is high among commercial farmers. Farmer attitudes, beliefs, and some demographic characteristics are useful identifiers of brand loyal farmers.brand loyalty, capital inputs, expendable inputs, farmer purchase decisions, Farm Management,
The Nature of Deeply Buried Ultraluminous Infrared Galaxies: A Unified Model for Highly Obscured Dusty Galaxy Emission
We present models of deeply buried ultraluminous infrared galaxy (ULIRG)
spectral energy distributions (SEDs) and use them to construct a
three-dimensional diagram for diagnosing the nature of observed ULIRGs. Our
goal is to construct a suite of SEDs for a very simple model ULIRG structure,
and to explore how well this simple model can (by itself) explain the full
range of observed ULIRG properties. We use our diagnostic to analyze archival
Spitzer Space Telescope IRS spectra of ULIRGs and find that: (1) In general,
our model does provide a comprehensive explanation of the distribution of
mid-IR ULIRG properties; (2) >75% (in some cases 100%) of the bolometric
luminosities of the most deeply buried ULIRGs must be powered by a
dust-enshrouded active galactic nucleus; (3) an unobscured "keyhole" view
through <~10% of the obscuring medium surrounding a deeply buried ULIRG is
sufficient to make it appear nearly unobscured in the mid-IR; and (4) the
observed absence of deeply buried ULIRGs with large PAH equivalent widths is
naturally explained by our models showing that deep absorption features are
"filled-in" by small quantities of foreground unobscured PAH emission (e.g.,
from the host galaxy disk) at the level of ~1% the bolometric nuclear
luminosity. The modeling and analysis we present will also serve as a powerful
tool for interpreting the high angular resolution spectra of high-redshift
sources to be obtained with the James Webb Space Telescope.Comment: 20 pages, 14 figures. Accepted for publication in the Ap
Use of Ultra-Thin Window Detectors for Biological Microanalysis
Films and bulk samples of Nylon, gelatin, Makrofol, epoxy resin, aminoplastic resin and sodium acetate have been used as models of biological samples. It is shown that the use of ultrathin window (UTW) detectors in scanning transmission and scanning electron microsopes permits the quantitative analysis of light elements, yielding a total element analysis with hydrogen estimated by difference or guesstimated .
Comparison with known concentrations or concentrations obtained by chemical analysis shows that X-ray microanalysis of sections by the peak to continuum ratio model and bulk samples by the φ(pz) model gives sufficiently accurate results for biological purposes. It is also shown that sections may be analysed by the standardless ratio model.
The application of UTW detectors to total element analysis by quantitative elemental imaging is demonstrated of bulk biological samples, which have been freeze-substituted, embedded in epoxy resin and surface polished. The possibility of imaging the oxygen content of frozen-hydrated bulk tissue samples which have been surface polished is also demonstrated. This may lead to the imaging of water distribution in frozen-hydrated bulk samples of biological tissues.
UTW detectors are also useful for detecting mass loss in organic samples by monitoring the decrease in oxygen counts and for detecting contamination by monitoring the increase in carbon counts. It is also shown that changes in carbon counts are good indicators of folds in sections
A Census of X-ray gas in NGC 1068: Results from 450ks of Chandra HETG Observation
We present models for the X-ray spectrum of the Seyfert 2 galaxy NGC 1068.
These are fitted to data obtained using the High Energy Transmission Grating
(HETG) on the Chandra X-ray observatory. The data show line and radiative
recombination continuum (RRC) emission from a broad range of ions and elements.
The models explore the importance of excitation processes for these lines
including photoionization followed by recombination, radiative excitation by
absorption of continuum radiation and inner shell fluorescence. The models show
that the relative importance of these processes depends on the conditions in
the emitting gas, and that no single emitting component can fit the entire
spectrum. In particular, the relative importance of radiative excitation and
photoionization/recombination differs according to the element and ion stage
emitting the line. This in turn implies a diversity of values for the
ionization parameter of the various components of gas responsible for the
emission, ranging from log(xi)=1 -- 3. Using this, we obtain an estimate for
the total amount of gas responsible for the observed emission. The mass flux
through the region included in the HETG extraction region is approximately 0.3
Msun/yr assuming ordered flow at the speed characterizing the line widths. This
can be compared with what is known about this object from other techniques.Comment: 39 pages, 12 figures, Ap. J. in pres
Scaling Symmetries of Scatterers of Classical Zero-Point Radiation
Classical radiation equilibrium (the blackbody problem) is investigated by
the use of an analogy. Scaling symmetries are noted for systems of classical
charged particles moving in circular orbits in central potentials V(r)=-k/r^n
when the particles are held in uniform circular motion against radiative
collapse by a circularly polarized incident plane wave. Only in the case of a
Coulomb potential n=1 with fixed charge e is there a unique scale-invariant
spectrum of radiation versus frequency (analogous to zero-point radiation)
obtained from the stable scattering arrangement. These results suggest that
non-electromagnetic potentials are not appropriate for discussions of classical
radiation equilibrium.Comment: 13 page
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