The preliminary results described here show that the adsorbability of uranyl ions by a highly stable MOF UiO-66 can be drastically enhanced by tailoring the missing-linker defects in this MOF. The combination of defect-induced functionality improvement with the acid-resistant nature of UiO-66 substantiates the applicability of this material for actinide capture from acidic media.

BackgroundCopy number variants contribute to genetic variation in birds. Analyses of copy number variants in chicken breeds had focused primarily on those from commercial varieties with nothing known about the occurrence and diversity of copy number variants in locally raised Chinese chicken breeds. To address this deficiency, we characterized copy number variants in 11 chicken breeds and compared the variation among these breeds.ResultsWe presented a detailed analysis of the copy number variants in locally raised Chinese chicken breeds identified using a customized comparative genomic hybridization array. We identified 833 copy number variants contained within 308 copy number variant regions. The median and mean sizes of the copy number variant regions were 14.6 kb and 35.1 kb, respectively. Of the copy number variant regions, 138 (45%) involved gain of DNA, 159 (52%) involved loss of DNA, and 11 (3%) involved both gain and loss of DNA. Principal component analysis and agglomerative hierarchical clustering revealed the close relatedness of the four locally raised chicken breeds, Shek-Ki, Langshan, Qingyuan partridge, and Wenchang. Biological process enrichment analysis of the copy number variant regions confirmed the greater variation among the four aforementioned varieties than among the seven other breeds studied.ConclusionOur description of the distribution of the copy number variants and comparison of the differences among the copy number variant regions of the 11 chicken breeds supplemented the information available concerning the copy number variants of other Chinese chicken breeds. In addition to its relevance for functional analysis, our results provided the first insight into how chicken breeds can be clustered on the basis of their genomic copy number variation.

We have demonstrated a record short wavelength lasing at 244.63 nm with TE dominant polarization from GaN quantum wells (QWs) at room temperature (RT). The optical threshold of 310 kW/cm 2 is comparable to state-of-the-art AlGaN QW lasers at similar wavelengths. The sample was grown on the AlN/sapphire template pesudomorphically. X-ray diffraction (XRD) shows unambiguous higherorder satellite peaks indicating a sharp interface amid the active region. The excitonic localization was revealed and studied by the photoluminescence (PL) and timeresolved PL (TRPL) spectroscopy at temperatures ranging from 15 K to RT. At 15 K, the multiple-component PL decay curves with the decay time varying from 62.6 to 2.77 ns at different energies confirmed the localized excitons. The peak energy of the temperature-dependent PL spectra exhibited the "S-shape" behavior; and the weak exciton localization with a small localization energy of 14.3 meV was observed. Therefore, even in the low temperature region, the escape possibility of excitons increased as the temperature rose. As a result, the fwhm of the emission spectra changed significantly when the temperature was below 150 K. Above 150 K, the PL decay shape changed from the two-component exponential decay to the single exponential decay, indicating complete delocalization of excitons. The work demonstrates the weak localization and thus smooth interface in the GaN/AlN active region, which are desirable for DUV lasers operating at RT.