B. Bose-Einstein condensation 70 IX. Future Directions 75 Acknowledgments 76 References 76 ''Laser Cooling and Trapping of Atoms,'' J. Opt. Soc. Am. B 6, No. 11, November 1989. Two more recent reviews (Metcalf and van der Straten, 1994; Adams and Riis, 1997) update a decade of developments since the early work recounted in the J. Opt. Soc. Am. B special issues. 2 For an introduction to current research in alkali-atom Bose-Einstein condensation see the special issue on Bose-Einstein condensation in the Journal of Research of the National Institute of Standards and Technology 101, No. 4, July-August 1996.

We report on the experimental observation of vortex tangles in an atomic Bose-Einstein condensate (BEC) of ;{87}Rb atoms when an external oscillatory perturbation is introduced in the trap. The vortex tangle configuration is a signature of the presence of a turbulent regime in the cloud. We also show that this turbulent cloud suppresses the aspect ratio inversion typically observed in quantum degenerate bosonic gases during free expansion. Instead, the cloud expands keeping the ratio between their axis constant. Turbulence in atomic superfluids may constitute an alternative system to investigate decay mechanisms as well as to test fundamental theoretical aspects in this field.

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The possibility of creating a Bose condensate of trapped atoms in a non-ground state is suggested. Such a nonequilibrium Bose condensate can be formed if one, first, obtains the conventional Bose condensate in the ground state and then transfers the condensed atoms to a non-ground state by means of a resonance pumping. The properties of ground and non-ground states are compared and plausible applications of such nonequilibrium condensates are discussed. 03.75.Fi

An approximate solution to the Gross-Pitaevskii equation for Bose-Einstein condensate in a spherical harmonic trap is suggested, which is valid in the whole interval of the coupling parameter, correctly interpolating between weak-coupling and strong-coupling limits. This solution is shown to be more accurate than the optimized Gaussian approximation as well as the Thomas-Fermi approximation. The derivation of the solution is based on the self-similar approximation theory. The possibility of obtaining interpolation formulas in the case of nonspherical traps is discussed. 03.75.Fi

Objective. In vivo studies of antimicrobial PDT in animal models of oral candidosis are scarce and the association of porphyrin and LED light has not been evaluated for in vivo photoinactivation of Candida. In this study the effectiveness of photodynamic therapy (PDT) on the inactivation of Candida albicans in vivo was evaluated. Study design. Seventy-one 6-week-old female Swiss mice were immunosuppressed, provided tetracycline to their drinking water, then orally swabbed with a suspension of C. albicans (10 7 CFU/mL). Four days after oral inoculation, PDT was performed on the dorsum of the tongue after topical administration of Photogem at 400, 500, or 1000 mg/L and followed 30 minutes later by illumination with LED light (305 J/cm 2 ) at 455 or 630 nm (n ϭ 5 each). After swabbing to recover yeast from the tongue, the number of surviving yeast cells was determined (CFU/mL) and analyzed by ANOVA and Holm-Sidak tests (P Ͻ .05). Animals were humanely killed, and the tongues surgically removed and processed for histological evaluation of presence of yeast and inflammatory reaction. Results. PDT resulted in a significant reduction in C. albicans recovered from the tongue (P Ͻ .001) when compared with mice from the positive control group. There was no difference between the concentrations of Photogem and LED light wavelengths used. Histological evaluation of the tongue revealed that PDT causes no significant adverse effects to the local mucosa. Conclusion. PDT promoted significant reduction in the viability of C. albicans biofilm without harming the tongue tissue.

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In vitro investigations of curcumin-mediated photodynamic therapy (PDT) are encouraging, but there is a lack of reliable in vivo evidence of its efficacy. This study describes the photoinactivation of Candida albicans in a murine model of oral candidiasis, using curcumin as a photosensitizer. Forty immunosuppressed mice were orally inoculated with C. albicans and after five days, they received topical curcumin (20, 40 and 80 μM) and illumination with LED light. The use of curcumin or light alone were also investigated. Positive control animals did not receive any treatment and negative control animals were not inoculated with C. albicans. The number of surviving yeast cells was determined and analyzed by ANOVA and Tukey's post-hoc test (α = 0.05). Histological evaluation of the presence of yeast and inflammatory reaction was also conducted. All exposures to curcumin with LED light caused a significant reduction in C. albicans viability after PDT, but the use of 80 μM curcumin associated with light was able to induce the highest log10 reduction in colony counts (4 logs). It was concluded that curcumin-mediated PDT proved to be effective for in vivo inactivation of C. albicans without harming the host tissue of mice.