Volatile organic compounds (VOCs) are an ever-growing hazard for health and environment due to their increased emissions and accumulation in the air. Quantum cascade laser-based infrared (QCL-IR) sensors hold significant promise for gas monitoring, thanks to their compact, rugged design, high laser intensity, and high molecule-specific detection capabilities within the mid-infrared spectrum's fingerprint region. In this work, tunable external cavity QCLs were complemented by an innovative germanium-on-silicon integrated optics waveguide sensing platform with integrated microlenses for efficient backside optical interfacing for the tunable laser spectrometer.
View Article and Find Full Text PDFAutologous breast reconstruction (ABR) uses a harvested tissue flap from the abdomen, posterior thigh, or buttocks to rebuild the breast postmastectomy. Identification of nerves for use in autologous sensate breast reconstruction flaps is an important surgical consideration as loss of breast sensation is a common risk of ABR. The posterior femoral cutaneous nerve (PFCN) and its branches supply sensory innervation to skin of the posterior thigh, leg, perineum, and buttocks, creating a feasible candidate for sensate profunda artery perforator (PAP) flaps for reestablishing breast sensation through ABR.
View Article and Find Full Text PDFFree-base porphyrins can be protonated, which significantly impacts their electronic and excited state properties. While excited state dynamics are well explored for either neutral or fully protonated porphyrins, the intermediate region has not yet been explored, although their potential implications for photocatalytic reactions are evident. This study explores how partial protonation affects the nature and properties of photoexcited states of tetrakis(4-carboxyphenyl)porphyrin (TCPP) using steady-state and nanosecond transient absorption spectroscopy.
View Article and Find Full Text PDFAzobenzene analogues of the tubulin polymerisation inhibitor combretastatin A4 (PSTs) were previously developed to optically control microtubule dynamics in living systems, with subsecond response time and single-cell spatial precision, by reversible photoswitching of their bioactivity with near-UV/visible light. First-generation PSTs were sufficiently potent and photoswitchable for use in live cells and embryos. However, the link between their seconds-scale and hours-scale bioactivity remained untested.
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