Microfabrication has greatly matured and proliferated in use amongst many disciplines. There has been great interest in micromachined flow sensors due to the benefits of miniaturization: low cost, small device footprint, low power consumption, greater sensitivity, integration with on-chip circuitry, etc. This paper reviews the theory of thermal flow sensing and the different configurations and operation modes available. Material properties relevant to micromachined thermal flow sensing and selection criteria are also presented. Finally, recent applications of micromachined thermal flow sensors are presented. Detailed tables of the reviewed devices are included.

The provided electrophysiological and immunohistochemical data provide strong support to the viability of the developed probe technology. Furthermore, the obtained data provide insights into further optimization of the probe design, including tip geometry, use of neurotrophic and anti-inflammatory drugs in the Matrigel coating, and placement of the recording sites.

The first electrochemical actuator with a Parylene bellows for intraocular drug delivery is presented in which the bellows separates the electrolysis actuation chamber from the drug reservoir. The Parylene bellows was fabricated using a novel polyethylene glycol (PEG)-molding process and mechanically characterized. Optimization of the gas generation efficiency of the actuators was performed. We achieved an efficiency approaching 80% and over 1.5 mm deflection with our actuator. Wireless operation was also demonstrated.

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Summary Objective The pathophysiology of sudden unexpected death in epilepsy (SUDEP) remains undetermined. Seizures are accompanied by respiratory dysfunction (RD). Postictal generalized EEG suppression (PGES) may follow generalized tonic-clonic seizures (GTCS). Following GTCS patients have impaired arousal and may be motionless. Patients with SUDEP are usually prone. Postictal immobility (PI) may contribute to SUDEP by not permitting repositioning of the head to allow unimpeded ventilation. To determine whether RD and/or ictal characteristics are associated with PI, we analyzed patients with GTCS in the Epilepsy Monitoring Unit. Method We investigated for associations between PI duration and: PGES, ictal/postictal oxygen saturation (SpO2), end-tidal CO2 (ETCO2), seizure localization, duration, and tonic and total convulsive phase duration. We investigated for linkage between PGES and these measures. Results 70 patients with 181 GTCS and available SpO2 and/or ETCO2 data were studied. Simple linear regression analysis by seizures showed that PI duration was associated with peak peri-ictal ETCO2 (p=0.03), duration of oxygen desaturation (p=0.005) and with SpO2 nadir (p=0.02). PI duration was not associated with tonic, convulsive phase or total seizure duration. Analysis by patients also showed significant association of PI with RD. Duration of PI was longer following seizures with PGES (p<0.001). PGES was not associated with the tonic, convulsive phase or total seizure duration. SpO2 nadir was lower in seizures with PGES (p=0.046), ETCO2 peak change (p=0.003) was higher and duration of ETCO2 elevation (p=0.03) was longer. Multivariable regression analysis showed that PGES and severe RD were associated with PI duration. Significance The duration of PI and presence of PGES are associated with peri-ictal RD. The duration of PI is also associated with the presence of PGES. Seizure duration or duration of the convulsive phase is not associated with PI or PGES. Interventions aimed at reversing impaired arousal and PI may reduce SUDEP risk.