Broadband Omnidirectional Light Trapping in Gold-Decorated ZnO Nanopillar Arrays.

The photoluminescence (PL) and reflectivity characteristics of zinc oxide nanopillars (ZnO-NPs) grown on indium-tin-oxide (ITO)-coated glasses were investigated. The room temperature PL showed bright white-light emission for the undoped ZnO-NPs grown at 600 °C, suggesting the close relation between the optical characteristic and the growth conditions being carried out for obtaining the present ZnO-NPs. The reflectivity of the as-grown ZnO-NPs array was about ∼29% with the wavelength of the incident light ranging from 200 to 1800 nm. Nevertheless, the reflectance reduced significantly to less than 9.9% when a layer of gold (Au) was deposited on ZnO-NPs by sputtering for 5 min, corresponding to more than 65% reduction in Au-coated ZnO-NPs (Au/ZnO-NPs). Moreover, the angle-resolved reflectance measurements on the present Au/ZnO-NPs array show an omnidirectional light-trapping characteristic. These remarkable characteristics, broadband and omnidirectional light-trapping of Au/ZnO-NPs, are attributed to the extended effective optical path of the incident light due to subwavelength scattering resulting from the presence of Au nanoparticles.

Tuning the magnetic properties of self-assembled BiFeO3-CoFe2O4 heteroepitaxy by magneto-structural coupling.

Magnetic and multiferroic nanocomposites with two distinct phases have been a topic of intense research for their profound potential applications in the field of spintronics. In addition to growing high-quality phase separated heteroepitaxial nanocomposites, the strain engineering that is conducive to enhance the tunability of material properties, in general, and the magnetic properties, in particular, is of utmost importance in exploring new possibilities. Here, we investigated the magneto-structural coupling between antiferromagnetic BiFeO3 (BFO) and ferrimagnetic CoFe2O4 (CFO) in self-assembled vertically aligned nanocomposites grown on LaAlO3 (LAO) and SrTiO3 (STO) substrates. We found that BFO exhibits tetragonal (T) and rhombohedral (R) structures as the stable phases and CFO has high magnetocrystalline anisotropy even in the form of nanocomposites. The temperature and magnetic field dependent magnetizations of T_BFO-CFO/LAO and R_BFO-CFO/STO nanocomposites primarily demonstrate the magnetoelastic coupling between these variants.

Field emission properties of gold nanoparticle-decorated ZnO nanopillars.

The structural and optoelectronic properties of ZnO nanopillars (ZnO-NPs) grown on Si substrates by the vapor transport deposition method were investigated. In particular, by varying the deposition duration and hence the morphology of the vertically aligned ZnO-NPs, the resultant field emission characteristics were systematically compared. In addition to identifying the advantageous field emission properties exhibited in the pencil-like ZnO-NPs, we observed that by adhering Au nanoparticles on the surface of the ZnO-NPs the turn-on field and the maximum current density can be drastically improved from 3.15 V/µm and 0.44 mA/cm(2) at 5 V/µm for the best ZnO-NPs to 2.65 V/µm and 2.11 mA/cm(2) at 5 V/µm for Au/ZnO-NPs, respectively. The enhancement of field emission characteristics that resulted from Au-nanoparticle decoration is discussed on the basis of charge-transfer-induced band structure modifications.

Music therapy for patients receiving spine surgery.

AIMS AND OBJECTIVES: The aim of this study was to evaluate the effects of music therapy on anxiety, postoperative pain and physiological reactions to emotional and physical distress in patients undergoing spinal surgery. BACKGROUND: Surgery-related anxiety and pain are the greatest concern of surgical patients, especially for those undergoing major procedures. DESIGN: A quasi-experimental study design was conducted in a medical centre in Taiwan from April-July 2006. METHODS: Sixty patients were recruited. The study group listened to selected music from the evening before surgery to the second day after surgery. The control group did not listen to music. Patients' levels of anxiety and pain were measured with visual analogue scales (VAS). Physiological measures, including heart rate, blood pressure and 24-hour urinalysis, were performed. RESULTS: The average age of the 60 patients was 62·18 (SD 18·76) years. The mean VAS score for degree of anxiety in the study group was 0·8-2·0, compared with 2·1-5·1 in the control group. The mean VAS score for degree of pain in the study group was 1·7-3·0, compared with 4·4-6·0 in the control group. The differences between the two groups in VAS scores for both anxiety (p = 0·018-0·001) and pain (p = 0·001) were statistically significant. One hour after surgery, the mean blood pressure was significantly lower in the study group than in the control group (p = 0·014), but no significant differences were found between the two groups in urine cortisol (p = 0·145-0·495), norepinephrine (p = 0·228-0·626) or epinephrine values (p = 0·074-0·619). CONCLUSIONS: Music therapy has some positive effects on levels of anxiety and pain in patients undergoing spinal surgery. RELEVANCE TO CLINICAL PRACTICE: Complementary music therapy can alleviate pain and anxiety in patients before and after spinal surgery.