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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 487 records · Page 27

System and method for repeated metal deposition-dewetting steps to form a nano-particle etching mask producing thicker layer of engraved metasurface

A method and system is disclosed for creating an optical component having a spatially controlled refractive index and uniform anti-reflective layer. The method may involve alternately depositing and dewetting two or more thin metal material layers on the substrate to form a mask having a spatially varying nano-particle distribution, and with an increased thickness beyond what could be achieved using a single, thick layer of the same material. The substrate may then be etched, using the mask, to imprint a spatially patterned nanostructure pattern on a surface the substrate in accordance with the mask.

Feigenbaum, Eyal↗

Bus repeater and bit injector for MIL-STD-1553/1760 communications bus

A fault insertion device (FID) comprises a transceiver and an FPGA. The transceiver receives signals from a MIL-STD-1553/1760 communications bus. The FPGA evaluates the signals received from the communications bus against a set of rules stored by the FPGA. Based upon the set of rules, the FPGA can selectively modify messages received from the communications bus prior to transmission to a remote terminal or a bus controller that is configured to communicate on the communications bus.

Krein, Jason P.↗

Establishment of FXS-A9 panel with a single human X chromosome from fragile X syndrome-associated individual

Highlights: • We established mouse A9 cells with human X chromosome from FXS carrier and patient. • FXS-associated CGG repeats were stably maintained in established rodent cells. • Epigenetic status of CGG repeat region were maintained in established rodent cells. • Human FMR1 expression in these cells was according to each CGG repeat length. Fragile X syndrome (FXS) is the most common inheritable form of intellectual disability. FMR1, the gene responsible for FXS, is located on human chromosome Xq27.3 and contains a stretch of CGG trinucleotide repeats in its 5′ untranslated region. FXS is caused by CGG repeats that expand beyond 200, resulting in FMR1 silencing via promoter hypermethylation. The molecular mechanism underlying CGG repeat expansion, a fundamental cause of FXS, remains poorly understood, partly due to a lack of experimental systems. Accumulated evidence indicates that the large chromosomal region flanking a CGG repeat is critical for repeat dynamics. In the present study, we isolated and introduced whole human X chromosomes from healthy, FXS premutation carriers, or FXS patients who carried disease condition-associated CGG repeat lengths, into mouse A9 cells via microcell-mediated chromosome transfer. The CGG repeat length-associated methylation status and human FMR1 expression in these monochromosomal hybrid cells mimicked those in humans. Thus, this set of A9 cells containing CGG repeats from three different origins (FXS-A9 panel) may provide a valuable resource for investigating a series of genetic and epigenetic CGG repeat dynamics during FXS pathogenesis.

60 APPLIED LIFE SCIENCES↗