Enhancing the light-extraction efficiency is the key issue for realizing highly efficient AlGaN-based ultraviolet light-emitting diodes (UV-LEDs). We introduced several features to improve the light extraction: a transparent AlGaN:Mg contact layer, a Rh mirror electrode, an AlN template on a patterned sapphire substrate, and encapsulation resin. The combination of the AlGaN:Mg contact layer and the Rh mirror electrode significantly improved the output power and the external quantum efficiency (EQE) of UV-LEDs. By introducing the aforementioned features, a maximum EQE of >20% at an emission wavelength of 275 nm and a 20-mA direct current was achieved.

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With the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is an urgent need for more rapid and simple detection technologies at the forefront of medical care worldwide.In this study, we evaluated the effectiveness of the Loopamp® 2019-SARSCoV-2 Detection Reagent Kit, which uses loop-mediated isothermal amplification (LAMP) technology. In this protocol, cDNA is synthesized from SARS-CoV-2 RNA using reverse transcriptase, followed by DNA amplification under isothermal conditions in one step. The RT-LAMP test kit amplified the targeted RNA of a SARS-CoV-2 isolate with a detection limit of 1.0 × 101 copies/μL, which was comparable to the detection sensitivity of quantitative reverse transcription PCR (RT-qPCR).Comparison with the results of RT-qPCR for 76 nasopharyngeal swab samples from patients with suspected COVID-19 showed a sensitivity of 100 % and a specificity of 97.6 %. In the 24 RNA specimens derived from febrile Japanese patients with or without influenza A, no amplification was observed using RT-LAMP. RT-LAMP could be a simple and easy-to-use diagnostic tool for the detection of SARS-CoV-2.

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Monocytes play a pivotal role in various human infectious and inflammatory diseases. To reveal a whole picture of pathophysiologic function of activated human monocytes, this study used the serial analysis of gene expression (SAGE) procedure in lipopolysaccharide (LPS)-stimulated human monocytes. A total of 35 874 tags corresponding to more than 12 000 different transcripts were sequenced. Comparison of gene expression profile with that of resting monocytes revealed the LPS-inducible gene expression profile. Many cytokines and chemokines, including interleukin (IL)-6, IL-1α, IL-1β, tumor necrosis factor (TNF)-α, macrophage inflammatory protein (MIP)-1β, MIP-2β, MIP-2α, liver and activation-regulated chemokine (LARC), MIP-1α, thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), regulated on activation, normal T cell expressed and secreted (RANTES), growth-regulated oncogene (GRO) α, and IL-8, were observed in the highest inducible transcripts. Other genes encoding plasminogen activator inhibitor type 2 (PAI-2), Hc-gp39, apolipoproteins, malate dehydrogenase, matrix metalloproteinase-9 (MMP-9), and cyclooxygenase (COX2) were also highly elevated in LPS-stimulated monocytes. Moreover, up-regulation of Naf1β, IL-7 receptor, adenosine receptor A2a, and many novel genes was newly identified. These results suggest that the LPS-inducible gene products may be involved in cell activation and migration, angiogenesis, tissue remodeling, and metabolism, and thus may orchestrate the inflammatory reactions. On the other hand, the expression of numerous sets of novel genes was discovered to be down-regulated on LPS stimulation. This study represents the first comprehensive analysis of LPS-inducible gene expression in human monocytes and provides tremendous novel information for the function of LPS-activated monocytes and targets for diagnosing, monitoring, and treating sepsis and various human infectious and inflammatory diseases.