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AlGaInAs-InP multi-quantum-well (MQW) continuous-wave Fabry–Perot laser diodes are exposed to 1.8 MeV protons at fluences up to 1   1013 p/cm2. The threshold current increases with fluence, with a maximum shift of over 180%. Minimal change in slope e ciency is observed. A substantial redshift in emission wavelength is observed at all fluence levels, while the wavelength free spectral range (FSR) remains constant. The wavelength shift persists even when measured at the same forward current for pre- and post-irradiation conditions, indicating that e ects of heating and plasma from the forward current are a second-order e ect. The series resistance was not significantly a ected by radiation exposure. Damage factor analysis reveals a value more than 100 times higher than that of previously studied lasers of these types, indicating high sensitivity to displacement events. For this laser, the dominant mechanism for the radiation-induced wavelength shift is likely a change in group refractive index and gain bandwidth due to radiation-induced defect levels within the bandgap, with minimal contributions from heating. System-level and hardness-assurance implications are discussed 

We designed a few polymyxin derivatives which exhibit broad-spectrum antimicrobial activity. Lead compound P1 could disrupt bacterial membranes rapidly without developing resistance, inhibit biofilms formed by E. coli , and exhibit excellent in vivo activity in an MRSA-infected thigh burden mouse model.