[Molecular Mechanism of a Rhesus D Variant Individual with RHD*845A/1227A].

OBJECTIVE: To explore the genetic mutation mechanism of a rare Rhesus D variant individual. METHODS: Regular serological assay was used for determination of Rh type for the sample. Indirect anti-human globulin test (IAT) was used to confirm the RhD antigen and screen the antibodies. D-screen reagent was used to analyze the RhD epitopes of the sample. RHD genotype and RHD zygosity testing of the sample were detected by palymerase chain reaction with sequence-specific primers (PCR-SSP). The full length coding region of RHD gene was sequenced. RHD mRNA was detected using reverse transcription polymerase chain reaction (RT-PCR). The PCR products were cloned and sequenced. RESULTS: The RhD blood group of the sample was determined as weak D, and the Rh phenotype was CcDEe. The antibody screening was negative. The sample tested with all monoclonal anti-Ds in D-screen showed the D epitope profiles as partial D types. The analysis of RHD gene sequence indicated that the individual with RHD c.845G/A and RHD c.1227G/A base heterozygosis. Three kinds of alternative splicing isoforms were obtained by TA cloning and sequencing. CONCLUSION: The object has RHD c.845G/A and RHD c.1227G/A mutation. This heterozygous mutation is responsible for the low expression of RhD antigen on the red blood cells of the sample.

Transparent ultraviolet photovoltaic cells.

Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

Enhanced responsivity of photodetectors realized via impact ionization.

To increase the responsivity is one of the vital issues for a photodetector. By employing ZnO as a representative material of ultraviolet photodetectors and Si as a representative material of visible photodetectors, an impact ionization process, in which additional carriers can be generated in an insulating layer at a relatively large electric field, has been employed to increase the responsivity of a semiconductor photodetector. It is found that the responsivity of the photodetectors can be enhanced by tens of times via this impact ionization process. The results reported in this paper provide a general route to enhance the responsivity of a photodetector, thus may represent a step towards high-performance photodetectors.