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The development of full-visible-spectrum phosphors is essential for next-generation light-emitting devices with better light quality. Herein, we report on a novel broad-band-emitting phosphor based on single-composition Al-doped ZnO phosphors. Under the UV excitation of 325 nm, the ZnO : Al phosphor exhibits a full spectrum emission in the visible wavelength range from 400 to 800 nm with a CIE chromaticity coordinate of (0.42, 0.48), a quantum efficiency of 43%, a color rendering index (CRI) of 74, a correlated color temperature (CCT) value of 3873 K and an activation energy of 0.22 eV. A prototype of a UV-pumped warm WLED with a high CRI of 87 and a CCT of 4067 K has been achieved by using only this broad-band-emitting Al3+-doped ZnO phosphor. The obtained results indicate that the single-composition Al3+-singly doped warm white emitting phosphor is a promising candidate for UV-pump warm white light-emitting diodes.

Changes in Mycobacterium leprae-induced lymphoproliferative responses and mediator release by leprosy patients’ lymphocytes were followed during multiple drug therapy (MDT). At the time of diagnosis, multibacillary (MB) patients who did not develop reactions responded to both sonicated M. leprae and synthetic disaccharide coupled to bovine serum albumin (ND-BSA) antigens, but those who would later develop reactions did not respond, even in the presence of added cytokines. The paucibacillary (PB) group initially had high responses to sonicated M. leprae but no response to ND-BSA, even in the presence of added cytokines. In the first year of treatment, the supernatants of PB patients’ cell cultures contained factors that enhanced the phytohaemagglutinin (PHA) response of normal cells. In contrast, those MB patients who did not develop reactions at a later stage produced culture supernatants that were inhibitory. Interestingly, the MB patients who later developed reactions during treatment, and did not initially respond to M. leprae, produced supernatants containing enhancing factors, like those of the PB group. Later on in the treatment, all patients had the same patterns: when response to M. leprae decreased from its highest level, inhibitory factors were produced. Further studies revealed that the supernatants which inhibited the PHA response of normal cells contained the active form of transforming growth factor-β1 (TGF-β1), whatever the disease type or treatment status of the donor. These TGF-β1 levels correlated directly with the degree of inhibition. Similarly, supernatants that neither inhibited nor enhanced PHA responses contained the highest levels of interleukin-10 (IL-10), while those from treated patients that enhanced contained the lowest levels of interleukin-4 (IL-4) and interferon-γ (IFN-γ). These cytokine correlations transcended the conventional disease classification, and imply that all patients pass through a sequence of patterns of immune response during treatment. These treatment-induced changes may explain occasional reports of response patterns at variance with the ‘immunological spectrum’ of leprosy. BB, borderlineBL, borderline lepromatousBT, borderline tuberculoidIFN-γ, interferon gammaIL-4, interleukin-4IL-10, interleukin-10MB, multibacillaryPB, paucibacillaryRT–PCR, reverse transcriptase–polymerase chain reactionLL, polar lepromatousTGF-β1, transforming growth factor-β1TT, tuberculoid.