John D. Albrecht

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Double-stranded RNA interference Templates for him-1, scc-1, scc-3, rec-8 and tim-1 RNA transcription were generated by PCR amplification from N2 genomic DNA with the use of the primer sets listed in Supplementary Table 4. The smc-3 template was amplified by PCR using T3 and T7 primers from the Kohara cDNA yk361c10. Double-stranded RNA (1–5 mg ml) was(More)
Near-junction thermal management is critical to achieving the promise of electronic and photonic devices using wide bandgap materials. In such devices, including GaN HEMTs in PAs, the thermal resistance associated with the "near-junction" region dominates the heat removal path and is often as large as the thermal resistance of all the other elements in the(More)
DARPA/MTO has sponsored electronics programs to exploit the unique combination of high intrinsic breakdown voltages, high electron saturation velocities, and large sheet carrier densities of the nitride material system. The NEXT program is pushing III-N-based HEMTs toward its operating frequency (size) scaling limits by simultaneously minimizing carrier(More)
Starting more than a decade ago, DARPA began funding the materials and device developments of group III-nitride electronics to push toward the limits of cutoff frequency, breakdown voltage, power density and reliability of GaN HEMTs. These transistors have the potential to realize RF power amplifiers with both high output power and power added-efficiency(More)
The crystal structure, electronic and magnetic properties of LaMn(7)O(12) ((LaMn(3)(3+))(A)Mn(4)(3+)O(12)) are investigated by GGA (LSDA) and GGA + U (LSDA + U) (0.0 ≤ U ≤ 5.0 eV) methods. Based on two experimentally refined structures (distinguished by the distortion parameter Δ, namely S(I) (Δ = 8.5 × 10(-5)) and S(II) (Δ = 25.0 × 10(-4))), GGA and GGA +(More)
The high-frequency modulation characteristics of GaAs-based bipolar cascade vertical cavity surface-emitting lasers operating at 980 nm with GaAs tunnel junctions and p-doped Al0.98Ga0.02As oxide apertures have been measured. We achieve -3 dB laser output modulations of 6.5 GHz for two-stage and 9.4 GHz for three-stage devices in response to small-signal(More)
A nodal Discontinuous Galerkin (DG) method is derived for the analysis of time-domain (TD) scattering from doubly periodic PEC/dielectric structures under oblique interrogation. Field transformations are employed to elaborate a formalism that is free from any issues with causality that are common when applying spatial periodic boundary conditions(More)
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