Bethe-hole polarization analyser for the magnetic vector of light.

The nature of light as an electromagnetic wave with transverse components has been confirmed using optical polarizers, which are sensitive to the orientation of the electric field. Recent advances in nanoscale optical technologies demand their magnetic counterpart, which can sense the orientation of the optical magnetic field. Here we report that subwavelength metallic apertures on infinite plane predominantly sense the magnetic field of light, establishing the orientation of the magnetic component of light as a separate entity from its electric counterpart. A subwavelength aperture combined with a tapered optical fibre probe can also serve as a nanoscale polarization analyser for the optical magnetic field, analogous to a nanoparticle sensing the local electric polarization. As proof of its functionality, we demonstrate the measurement of a magnetic field orientation that is parallel to the electric field, as well as a circularly polarized magnetic field in the presence of a linearly polarized electric field.

3-dimensional local field polarization vector mapping of a focused radially polarized beam using gold nanoparticle functionalized tips.

We have measured local electric field polarization vectors in 3-dimensional space on the nanoscale. A radial polarized light is generated by using a radial polarization converter and focused by an objective lens. Gold nanoparticle functionalized tips are used to scatter the focused field into the far-field region. Two different methods, rotational analyzer ellipsometry and Stokes parameters, are used in determining the polarization state of the scattered light. Two methods give consistent results with each other. Three dimensional local polarization vectors could be reconstructed by applying back transformation of the fully characterized polarizability tensor of the tip.

Coherent exciton-surface-plasmon-polariton interaction in hybrid metal-semiconductor nanostructures.

We report measurements of a coherent coupling between surface plasmon polaritons (SPP) and quantum well excitons in a hybrid metal-semiconductor nanostructure. The hybrid structure is designed to optimize the radiative exciton-SPP interaction which is probed by low-temperature, angle-resolved, far-field reflectivity spectroscopy. As a result of the coupling, a significant shift of approximately 7 meV and an increase in broadening by approximately 4 meV of the quantum well exciton resonance are observed. The experiments are corroborated by a phenomenological coupled-oscillator model predicting coupling strengths as large as 50 meV in structures with optimized detunings between the coupled exciton and SPP resonances. Such a strong interaction can, e.g., be used to enhance the luminescence yield of semiconductor quantum structures or to amplify SPP waves.

Quantitative analysis of the outpatient oral case presentation: piloting a method.

OBJECTIVE: To measure the content of oral outpatient case presentations and to assess the correlation of objective assessments of this content with subjective ratings provided by the clinic attending physician. DESIGN: Blinded assessment via audiotape of 36 oral case presentations of new patient evaluations by 23 medical residents. SETTING: Outpatient general medical clinic. PARTICIPANTS: Duke University Medical Center medical residents during their outpatient rotation. MEASUREMENTS AND MAIN RESULTS: Important deficiencies were found in oral case presentation content. Specifically, psychosocial data were often missing (employment history) was mentioned in 28% of presentations; illicit drug use, in 17%; household social structure, in 11%; sexual history, in 6%). An assessment and a plan were mentioned only 56% and 69% of the time, respectively. No correlation was seen between an objective "content score" and the attending physician's subjective rating of the quality of the presentation (r = 0.09). CONCLUSIONS: 1) The outpatient care presentation can be quantitatively assessed in a simple, straightforward manner; 2) outpatient case presentations have important deficiencies in content; and 3) preceptors' evaluations of case presentations may be based upon factors other than content of the presentation.

Black hairy tongue.

Black hairy tongue is a benign disorder characterized by hypertrophy of the filiform papillae of the tongue. A brownish-black discoloration of the papillae occurs. The etiology is unclear, but the disorder has been associated with numerous predisposing conditions. Although black hairy tongue is usually cured by removal of these factors, a variety of measures, particularly brushing of the tongue, may aid in resolution.

Measurement and improvement of humanistic skills in first-year trainees.

The American Board of Internal Medicine (ABIM) has recently emphasized the development of humanistic skills in trainees. Using video technology, transition outpatient visits of first-year house officers in a primary care training program were evaluated for the presence or absence of nine humanistic skills before and after the initiation of an instructional program to reinforce the skills. Thirteen videotaped PGY-1 encounters constituted the preintervention group and 16 videotaped PGY-1 encounters constituted the postintervention group. The preintervention group performed a mean of 1.38 skills while the postintervention group performed a mean of 3.56 skills, a statistically significant improvement (p less than 0.05). The authors conclude that an educational approach that focuses on specific elements of interactions facilitates the incorporation of skills associated with humane medical care.