Publications by authors named "R Karlicek"

Respiratory interventions including noninvasive ventilation, continuous positive airway pressure and high-flow nasal oxygen generated infectious aerosols may increase risk of airborne disease (SARS-CoV-2, influenza virus) transmission to healthcare workers. We developed and tested a prototype portable UV-C device to sterilize high flows of viral-contaminated air from a simulated patient source at airflow rates of up to 100 l/m. Our device consisted of a central quartz tube surrounded 6 high-output UV-C lamps, within a larger cylinder allowing recirculation past the UV-C lamps a second time before exiting the device.

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We present a flexible, scalable, and low-noise design scheme for coupling free-space light into a silicon-on-insulator (SOI) electronic-photonic integrated circuit. The proposed scheme utilizes arrays of grating couplers with compact, inverse-designed power combining networks to couple a distributed optical collection area to a single output waveguide, forming a photonic antenna. Fabrication density compliance is maintained regardless of the antenna size, and the collection area can be scaled while maintaining a fixed noise floor.

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Respiratory interventions including noninvasive ventilation, continuous positive airway pressure and high-flow nasal oxygen generated infectious aerosols may increase risk of airborne disease (SARS-CoV-2, influenza virus) transmission to healthcare workers. We developed/tested a prototype portable UV-C device to sterilize high flows of viral-contaminated air from a simulated patient source at airflow rates of up to 100 l/m. Our device consisted of a central quartz tube surrounded 6 high-output UV-C lamps, within a larger cylinder allowing recirculation past the UV-C lamps a second time before exiting the device.

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Particulate respirators such as N95s are an essential component of personal protective equipment (PPE) for front-line workers. This study describes a rapid and effective UVC irradiation system that would facilitate the safe re-use of N95 respirators and provides supporting information for deploying UVC for decontamination of SARS-CoV-2 during the COVID-19 pandemic. To assess the inactivation potential of the proposed UVC germicidal device as a function of time by using 3 M 8211-N95 particulate respirators inoculated with SARS-CoV-2.

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Article Synopsis
  • The study examined how multicolor pulsed LED light affects the growth and antioxidant properties of lettuce "Defender," comparing continuous and pulsed light types at various frequencies while keeping total light exposure constant.
  • Lettuce under pulsed lighting showed significant improvements in growth metrics—fresh biomass increased by ~32%, dry biomass by ~36%, and leaf area by ~48%—along with enhanced photosynthetic rates and higher concentrations of chlorophyll and carotenoids.
  • The phenolic and antioxidant properties varied by the pulsed light frequency, with the 1 kHz treatment yielding the best results for phenol content and antioxidant activity, suggesting that using pulsed LED lights in indoor farming could enhance crop quality and energy efficiency.
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