Surface plasmon assisted optical nonlinearities of uniformly oriented metal nano-ellipsoids in glass.

The nonlinear optical properties of nanocomposites consisting of non-spherical silver nanoparticles in glass matrix have been studied using the femtosecond Z-scan technique. The spheroidal nanoparticles were uniformly oriented along a common direction. By polarization sensitive studies, longitudinal and transverse plasmon resonances can be addressed separately. A sign reversal in optical nonlinearity from negative to positive is observed while switching the light interaction from near to non-resonant regime, which can be done by simply rotating the light polarization by 90°. Studying samples with different aspect ratio, we obtained the dispersion of third-order nonlinearity in the near-resonant regime, showing an enhancement of the nonlinear processes by more than two orders of magnitude due to the electric field enhancement at the surface plasmon resonance.

Directionally selective optical limiting of femtosecond pulses in simple transparent two-layer systems.

Directionally selective nonlinear transmission behavior has been observed for simple glass-based two-layer systems in Z-scan experiments employing femtosecond pulses at a wavelength of λ=800 nm. Glass sheets of 1 mm thickness with a very thin surface layer (~2 µm) containing spherical Ag nanoparticles have been studied. In these samples, irradiating from the substrate side causes a strong transmission decrease via self-focusing of the beam and subsequent two-photon absorption in the thin layer, whereas the reverse direction may pass the sample without loss. This anisotropic optical limiting is discussed in terms of a numerical model in the limit of thin samples with respect to the Rayleigh range of the laser beam.

Feasibility and reliability of clinical coding surveillance for the routine monitoring of adverse drug events in New Zealand hospitals.

AIM: To explore the feasibility and reliability of Clinical Coding Surveillance (CCS) for the routine monitoring of Adverse Drug Events (ADE) and describe the characteristics of harm identified through this approach in a large district health board (DHB). METHOD: All hospital admissions at Waitemata DHB from 2015 to 2016 with an ADE-related ICD10-AM code of Y40-Y59, X40-X49 or T36-T50 were extracted from clinical coded data. The data was analysed using descriptive statistics, statistical process control and Pareto charts. Two clinicians assessed a random sample of 140 ADEs for their accuracy against what was clinically documented in medical records. RESULTS: A total of 11,999 ADEs were identified in 244,992 admissions (4.9 ADEs per 100 admissions). ADEs were more prevalent in older adults and associated with longer average length of stays and medicines such as analgesics, antibiotics, anticoagulants and diuretics. Only 2,164 (18%) of ADEs were classified as originating within hospital. Of ADEs originating outside of the hospital, the main causes were poisoning by psychotropics, anti-epileptics and anti-parkinsonism agents and non-opioid analgesics. Clinicians agreed that 91% of ADE positive admissions were accurately classified as per clinical documentation. CONCLUSION: CCS is a feasible and reliable approach for the routine monitoring of ADEs in hospitals.