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Two valley ensemble Monte Carlo simulations have been performed to investigate the electronic transport properties of bulk GaNxAs1-x alloys where the nitrogen concentration x ≤ 0.02 (2%). We have investigated these properties using two separate approaches, 1) through simulation of GaAs using the standard Kane model with the addition of isolated and pair state nitrogen scattering mechanisms and 2) approximating the lower 'mixed state' band that arises from the use of band-anticrossing model with an analytic function that implements the inflection point (for concentrations >1%). From the steady-state properties, we find that the nitrogen scattering model produces a better fit with other results, both theoretical and experimental. We also comment on the transient properties of GaNxAs1-x, noting that the velocity overshoot peaks are of a much lower velocity than is found in GaAs at comparable field strengths, and through the use of model 2, that negative effective mass states have a significant role in the transient behavior. We find that the system takes much longer to reach equilibrium when compared to bulk GaAs in both models, and through the use of model 2, there is a significant population of negative effective mass states when the system is subjected to higher fields. [ABSTRACT FROM AUTHOR]

The invention of imaginary worlds ("paracosms") is a creative activity of middle childhood that has previously been investigated primarily with retrospective adult reports and biographical accounts. In descriptions collected from 8- to 12-year-old children, the prevalence was 16.9% in Study 1 (n = 77) and 17.4% in Study 2 (n = 92). Children with and without paracosms did not differ in verbal comprehension, divergent thinking (Studies 1 and 2) or working memory (Study 2). However, children with paracosms had more difficulty with inhibitory control (Study 2) and had higher creativity scores on a story-telling task (Studies 1 and 2). Paracosms provided a vehicle for stories associated with imaginary companions and/or for developing complex narratives alone or with friends. [ABSTRACT FROM AUTHOR]

In non-stationary wear conditions, characterized by intermittent pulses of moderate or heavy sweating, a garment with a good moisture buffering action can improve comfort. This is consistent with the common consumer belief that clothing manufactured from hygroscopic natural fibers (e.g., wool or cotton) provides better breathability. The current work describes a new approach for measuring dynamic moisture buffering potential using the sweating guarded hotplate instrument in a novel mode of operation. A fabric test sample is placed on the hotplate following the normal procedure for dry mode testing but with the relative humidity of the surrounding environment set to a low value (45%). After equilibration, the relative humidity is rapidly increased to a high value (85%). In the case of hygroscopic samples, a transient reduction in the heat required to maintain the hotplate at its fixed temperature is observed. It is demonstrated that the area of this transient peak is a measure of the water vapor absorbed during this transition, that is, the moisture buffering potential of the test specimen. A key to this new approach is that the heat of sorption per gram of water vapor absorbed is approximately the same for a wide range of natural and synthetic fibers commonly used in clothing. Using matched knitted fabrics manufactured from wool, cotton or polyester, the technique detected the heat released from light weight fabrics and the performance of the different fiber types is clearly distinguished. [ABSTRACT FROM AUTHOR]

The mechanism of dry heat flow through lofty nonwoven structures (i.e. thermal resistance) as occurs in quilts has been established. By contrast, there is a scarcity of published information on the water vapor transport properties. This work explores the thermal and water vapor transport properties of a number of different quilt samples with a focus on identifying fiber type effects. Both commercial product and matched laboratory samples were examined. Steady-state thermal resistance and water vapor resistance measurements confirmed that both properties are primarily determined by sample thickness and are largely independent of fiber type. Experiments were also undertaken to observe transient effects. Test samples were initially equilibrated on a ‘dry’ guarded hotplate (35 ± 0.1℃) in a low relative humidity environment (45%). The relative humidity was then rapidly increased to 85%. Compared to polyester, wool samples exhibited a large reduction in the heat flux required to maintain the hotplate temperature. This transient peak lasted for in excess of 1000 seconds. The magnitude of this transient peak in heat flux was proportional to the quantity of wool in the sample and is believed to be associated with the known exothermic nature of water vapor absorption by wool as relative humidity increases. Based on the published values of the heat of water absorption of wool it is estimated that this additional transient heat source is significant relative to a typical human resting metabolic rate and so the effect may be of practical relevance in the bedding environment. [ABSTRACT FROM AUTHOR]

As interest in protein–protein interactions and other previously-undruggable targets increases, medicinal chemists are returning to natural products for design inspiration toward molecules that transcend the paradigm of small molecule drugs. These compounds, especially peptides, often have poor ADME properties and thus require a more nuanced understanding of structure-property relationships to achieve desirable oral bioavailability. Although there have been few clinical successes in this chemical space to date, recent work has identified opportunities to introduce favorable physicochemical properties to peptidic macrocycles that maintain activity and oral bioavailability. [ABSTRACT FROM AUTHOR]