Transport Measurements of the Heavy Fermion Superconductor CeCu2Si2 Under Pressure

Superconducting and normal state properties of a single crystal of CeCu₂Si₂ have been investigated by resistivity measurements under hydrostatic pressure and magnetic field. The low temperature resistivity behaviour ( = ₀ + AT ², which is observed up to a temperature T _A) is considered within the self-consistent renormalized (SCR) spin fluctuation model. Contrary to the model predictions, the product AT ² _A increases on approaching the quantum critical point (QCP). The temperature dependence of the upper critical field is analyzed assuming strong coupling and an intermediate regime between the clean and dirty limits. Both the low temperature resistivity behaviour at high pressure and the parameters deduced from the fits of H _c2 point to a pressure induced decrease of the quasi-particle effective mass m*. The anisotropy of the initial slope of H _c2(T) and therefore that of the effective mass was found to change under pressure.     

Spontaneous emission efficiency of compressively strained 1.5 mu m MQW lasers

The spontaneous emission efficiency of 1.5 mu m compressively strained MQW lasers was found to be higher than that of comparable unstrained devices. The activation energy for Auger recombination was higher in the strained devices. Both effects were explained in terms of a reduction in the hole mass by strain.<>     

Forgiveness and relationship satisfaction: Mediating mechanisms.

Although the ability to forgive transgressions has been linked to overall relationship satisfaction, the mechanisms that mediate this association have not been established. We propose that the tendency to forgive a romantic partner increases relationship satisfaction via increased relational effort and decreased negative conflict. In two studies, we used structural equations modeling to examine these variables as potential mechanisms that drive this association. In Study 1 (N = 523) and Study 2 (N = 446) we found that these variables significantly mediated the association between forgiveness and relationship satisfaction. The findings were robust when examined concurrently and longitudinally, across multiple measures of forgiveness, and when accounting for baseline relationship satisfaction and interpersonal commitment. These two mechanisms parallel theorized positive and negative dimensions of forgiveness and the motivational transformation that is said to underlie forgiveness. Theoretical implications and implications for intervention are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Application of Ozonated Dry Ice (ALIGAL™ Blue Ice) For Packaging and Transport in the Food Industry

Abstract: Dry ice is used by meat and poultry processors for temperature reduction during processing and for temperature maintenance during transportation. ALIGAL? Blue Ice (ABI), which combines the antimicrobial effect of ozone (O₃) along with the high cooling capacity of dry ice, was investigated for its effect on bacterial reduction in air, in liquid, and on food and glass surfaces. Through proprietary means, O₃ was introduced to produce dry ice pellets to a concentration of 20 parts per million (ppm) by total weight. The ABI sublimation rate was similar to that of dry ice pellets under identical conditions, and ABI was able to hold the O₃ concentration throughout the normal shelf life of the product. Challenge studies were performed using different microorganisms, including E. coli, Campylobacter jejuni, Salmonella, and Listeria, that are critical to food safety. ABI showed significant (P < 0.05) microbial reduction during bioaerosol contamination (up to 5‐log reduction of E. coli and Listeria), on chicken breast (approximately 1.3‐log reduction of C. jejuni), on contact surfaces (approximately 3.9 log reduction of C. jejuni), and in liquid (2‐log reduction of C. jejuni). Considering the stability of O₃, ease of use, and antimicrobial efficacy against foodborne pathogens, our results suggest that ABI is a better alternative, especially for meat and poultry processors, as compared to dry ice. Further, ABI can potentially serve as an additional processing hurdle to guard against pathogens during processing, transportation, distribution, and/or storage. Practical Application: A new product known as ALIGAL? Blue Ice (ABI) incorporates ozone in dry ice pellets, combining the high cooling capacity of dry ice pellets and the antimicrobial efficacy of ozone. This study evaluated the antimicrobial efficacy of ABI compared to dry ice under potential commercial processing conditions, specifically examining the impact on airborne, surface, moisture, and food contamination. Treatment with ABI resulted in higher reductions of bacteria with airborne contamination, on chicken breast, on surfaces, and in liquid compared to dry ice. Thus, ABI can serve as an additional processing hurdle to guard against pathogens during food processing and storage.     

Improved simulated annealing with step width adaptation for Langmuir probe tuning

In a previous investigation, a simulated annealing (SA) method was developed to optimize 14 Fourier terms in a radio-frequency waveform for active compensation of a Langmuir probe system. This approach was shown to find better solutions in less time than skilled human operators. However, variations in fitness indicated that the SA algorithm did not always find the precise global solution, although it came consistently close to it. This variability was caused by the limited number of fitness evaluations available due to time constraints. In this research, the chosen maximum step width has been shown to have a significant effect on the overall performance of the algorithm. A scaling function has been developed to adapt the maximum step width of the SA algorithm, on-line, as a function of the number of elapsed iterations. The modified algorithm has been shown to find fitter solutions with reduced variability in fitness.     

Seeing it their way: Evidence for rapid and involuntary computation of what other people see.

In a series of three visual perspective-taking experiments, we asked adult participants to judge their own or someone else's visual perspective in situations where both perspectives were either the same or different. We found that participants could not easily ignore what someone else saw when making self-perspective judgments. This was observed even when participants were only required to take their own perspective within the same block of trials (Experiment 2) or even within the entire experiment (Experiment 3), i.e. under conditions which gave participants a clear opportunity to adopt a strategy of ignoring the other person's irrelevant perspective. Under some circumstances, participants were also more efficient at judging the other person's perspective than at judging their own perspective. Collectively, these results suggest that adults make use of rapid and efficient processes to compute what other people can see. (PsycINFO Database Record (c) 2010 APA, all rights reserved)