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An exploratory study of single parents raising a child with developmental disabilities
The purpose of this study was to explore the unique experiences and specific needs of single parent families while assessing their level of stress raising a developmentally disabled child
In situ XAFS Study of Palladium Electrodeposition at the Liquid/Liquid Interface
We report the use of XAFS (X-ray absorption fine structure) as an in situ method to follow the electrochemically driven deposition of palladium nanoparticles at a liquid/liquid interface. A novel glass/plastic hybrid electrochemical cell was used to enable control of the potential applied to the liquid/liquid interface. In situ measurements indicate that the nucleation of metallic nanoparticles can be triggered through chronoamperometry or cyclic voltammetry. In contrast to spontaneous nucleation at the liquid/liquid interface, whereby fluctuations in Pd oxidation state and concentration are observed, under a fixed interfacial potential the growth process occurs at a steady rate leading to a build-up of palladium at the interface. Raman spectroscopy of the deposit suggests that the organic electrolyte binds directly to the surface of the deposited nanoparticles. It was found that the introduction of citric acid results in the formation of spherical nanoparticles at the interface
Developing an e-infrastructure for social science
We outline the aims and progress to date of the National Centre for e-Social
Science e-Infrastructure project. We examine the challenges faced by the project, namely in
ensuring outputs are appropriate to social scientists, managing the transition from research
projects to service and embedding software and data within a wider infrastructural
framework. We also provide pointers to related work where issues which have ramifications
for this and similar initiatives are being addressed
School Food Service Training: Breakfast Evaluation 2017
This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu. Report design: Anna Alba
Carnot cycle for an oscillator
Carnot established in 1824 that the efficiency of cyclic engines operating
between a hot bath at absolute temperature and a bath at a lower
temperature cannot exceed . We show that linear
oscillators alternately in contact with hot and cold baths obey this principle
in the quantum as well as in the classical regime. The expression of the work
performed is derived from a simple prescription. Reversible and non-reversible
cycles are illustrated. The paper begins with historical considerations and is
essentially self-contained.Comment: 19 pages, 3 figures, sumitted to European Journal of Physics Changed
content: Fluctuations are considere
Feedforward and feedback projections of caudal belt and parabelt areas of auditory cortex: refining the hierarchical model
Our working model of the primate auditory cortex recognizes three major regions (core, belt, parabelt), subdivided into thirteen areas. The connections between areas are topographically ordered in a manner consistent with information flow along two major anatomical axes: core-belt-parabelt and caudal-rostral. Remarkably, most of the connections supporting this model were revealed using retrograde tracing techniques. Little is known about laminar circuitry, as anterograde tracing of axon terminations has rarely been used. The purpose of the present study was to examine the laminar projections of three areas of auditory cortex, pursuant to analysis of all areas. The selected areas were: middle lateral belt (ML); caudomedial belt (CM); and caudal parabelt (CPB). Injections of anterograde tracers yielded data consistent with major features of our model, and also new findings that compel modifications. Results supporting the model were: (1) feedforward projection from ML and CM terminated in CPB; (2) feedforward projections from ML and CPB terminated in rostral areas of the belt and parabelt; and (3) feedback projections typified inputs to the core region from belt and parabelt. At odds with the model was the convergence of feedforward inputs into rostral medial belt from ML and CPB. This was unexpected since CPB is at a higher stage of the processing hierarchy, with mainly feedback projections to all other belt areas. Lastly, extending the model, feedforward projections from CM, ML, and CPB overlapped in the temporal parietal occipital area (TPO) in the superior temporal sulcus, indicating significant auditory influence on sensory processing in this region. The combined results refine our working model and highlight the need to complete studies of the laminar inputs to all areas of auditory cortex. Their documentation is essential for developing informed hypotheses about the neurophysiological influences of inputs to each layer and area
Toedienen van drijfmest in mais (vervolgonderzoek 1985 - 1987) = Slurry application in maize (continued research 1985 - 1987) : verslag van een onderzoek op ROC Heino (proefveld Hulsen) tussen 1985 en 1987 (PAGV 1420/IB 3041)
Evolution of Soil Carbon Storage and Morphometric Properties of Afforested Soils in the U.S. Great Plains
The objective of this project was to use detailed soil profi le descriptions and soil carbon analyses to determine the soil C sequestration potential of tree planting across climatic gradients in the U.S. Great Plains. Tree windbreak age ranged from 19 to 70 years and age of cultivation from 22 to ~110 years. At each site, soil pits were prepared within the tree planting, the adjacent crop fi elds, and nearby undisturbed grassland. Windbreak soils had consistently thicker soil organic carbon (SOC)- enriched A or A+AB horizons when compared to the crop fi elds. The thickness of A or A+AB horizons in the windbreak soils were comparable to the undisturbed grassland soils. A linear relationship was detected between the difference in A+AB thickness of soils beneath windbreaks and undisturbed grasslands and a climate index (hydrothermal coeffi cient, HTC). These results indicate that tree windbreaks with more cool and moist climate conditions are more favorable for SOC accumulation in the surface soil. The relationship between SOC accumulation and climate factors enables the estimation of soil carbon stocks in existing windbreaks and the prediction of potential carbon sequestration of future plantings
Backbone-driven host-dopant miscibility modulates molecular doping in NDI conjugated polymers
Molecular doping is the key to enabling organic electronic devices, however, the design strategies to maximize doping efficiency demands further clarity and comprehension. Previous reports focus on the effect of the side chains, but the role of the backbone is still not well understood. In this study, we synthesize a series of NDI-based copolymers with bithiophene, vinylene, and acetylenic moieties (P1G, P2G, and P3G, respectively), all containing branched triethylene glycol side chains. Using computational and experimental methods, we explore the impact of the conjugated backbone using three key parameters for doping in organic semiconductors: energy levels, microstructure, and miscibility. Our experimental results show that P1G undergoes the most efficient n-type doping owed primarily to its higher dipole moment, and better host–dopant miscibility with N-DMBI. In contrast, P2G and P3G possess more planar backbones than P1G, but the lack of long-range order, and poor host–dopant miscibility limit their doping efficiency. Our data suggest that backbone planarity alone is not enough to maximize the electrical conductivity (σ) of n-type doped organic semiconductors, and that backbone polarity also plays an important role in enhancing σ via host–dopant miscibility. Finally, the thermoelectric properties of doped P1G exhibit a power factor of 0.077 μW m−1 K−2, and ultra-low in-plane thermal conductivity of 0.13 W m−1K−1 at 5 mol% of N-DMBI, which is among the lowest thermal conductivity values reported for n-type doped conjugated polymers
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