Room-temperature operation of GaAs Bragg-mirror lasers

Room-temperature operation of GaAs distributed Bragg reflector lasers is reported. The diodes are fabricated from conventional double heterostructures involving only a single step of liquid-phase epitaxy. For gratings with a period of 3700 Å, the diodes lased at 8770 Å, which corresponds to the high-absorption side of the spontaneous emission spectrum. Thresholds as low as 6 kA/cm^2 have been realized

An Exploratory Study of Segmenting Visitors to a Community Festival

Abstract Understanding motivations of festival visitors is one of critical issues for learning about the visitors’ behaviors and intentions for some specific festivals and such knowledge will help festival sponsors customize and market their event products to customer. The purpose of this study is twofold. First, an attempt is made to identify visitors’ motivations for an art festival. Second, the designated motivations serve as a foundation to segment visitors into various groups. For that, a survey based on previous studies was administrated in Central Minnesota, USA and a total of 156 questionnaires were completed in 2010. Five factors of motivations were extracted after factor analysis and reliability test, including novelty, exploration, family gathering, recovering equilibrium, and socialization. Later, all participants were segmented into two groups based on their motivations, i.e., highly motivated and lower motivated group. These two groups were different on some social demographics and festival participation behaviors. The theoretical and practical implications are discussed

Second Cluster Integral and Excluded Volume Effects for the Pion Gas

The quantum mechanical formula for Mayer's second cluster integral for the gas of relativistic particles with hard-core interaction is derived. The proper pion volume calculated with quantum mechanical formula is found to be an order of magnitude larger than its classical evaluation. The second cluster integral for the pion gas is calculated in quantum mechanical approach with account for both attractive and hard-core repulsive interactions. It is shown that, in the second cluster approximation, the repulsive pion-pion-interactions as well as the finite width of resonances give important but almost canceling contributions. In contrast, an appreciable deviation from the ideal gas of pions and pion resonances is observed beyond the second cluster approximation in the framework of the Van der Waals excluded-volume model.Comment: 29 pages, Latex, 9 PS-figure

Antibody-Dependent Enhancement (ADE) of influenza infection and its possible role in the pathogenesis of influenza

Poster Presentations: P05postprintThe International Symposium on 'Surveillance and Discovery in Respiratory and Other Emerging Infections', Phnom Penh, Cambodia, 29-31 May 2011

Antibody-Dependent Enhancement (ADE) of infection and its possible role in the pathogenesis of influenza

Poster Presentationpublished_or_final_versionAnnual Scientific Meeting of the Institut Pasteur International Network, Hong Kong, China, 22-23 November 2010. In BMC Proceedings, 2011, v. 5, suppl. 1, p. 6

Van der Waals Excluded Volume Model of Multicomponent Hadron Gas

A generalization of the Van der Waals excluded volume procedure for the multicomponent hadron gas is proposed. The derivation is based on the grand canonical partition function for the system of particles of several species interacting by hard core potentials. The obtained formulae for thermodynamical quantities are consistent with underlying principles of statistical mechanics as well as with thermodynamical identities. The model can be applied to the analysis of experimental data for particle number ratios in relativistic nucleus-nucleus collisions.Comment: 8 page

Modular detergents tailor the purification and structural analysis of membrane proteins including G-protein coupled receptors

Detergents enable the purification of membrane proteins and are indispensable reagents instructural biology. Even though a large variety of detergents have been developed in the lastcentury, the challenge remains to identify guidelines that allowfine-tuning of detergents forindividual applications in membrane protein research. Addressing this challenge, here weintroduce the family of oligoglycerol detergents (OGDs). Native mass spectrometry (MS)reveals that the modular OGD architecture offers the ability to control protein purificationand to preserve interactions with native membrane lipids during purification. In addition to abroad range of bacterial membrane proteins, OGDs also enable the purification and analysisof a functional G-protein coupled receptor (GPCR). Moreover, given the modular design ofthese detergents, we anticipatefine-tuning of their properties for specific applications instructural biology. Seen from a broader perspective, this represents a significant advance forthe investigation of membrane proteins and their interactions with lipids

Minimum Renyi and Wehrl entropies at the output of bosonic channels

The minimum Renyi and Wehrl output entropies are found for bosonic channels in which the signal photons are either randomly displaced by a Gaussian distribution (classical-noise channel), or in which they are coupled to a thermal environment through lossy propagation (thermal-noise channel). It is shown that the Renyi output entropies of integer orders z>1 and the output Wehrl entropy are minimized when the channel input is a coherent state.Comment: Minimal revision. Accepted for publication on Phys. Rev.