Faculty Bibliography

The literature supports that organizations that create working conditions with positive practice environments improve nurses' job satisfaction and reduce turnover in hospital settings (Havens & Johnston, 2004; International Council of Nurses [ICN], 2007). Positive practice environments promote quality nursing care and better patient outcomes. However, in South America, there are no instruments to measure the nursing practice environment in a hospital setting. The purpose of this research was to examine the validity and reliability of a Spanish translation of the Practice Environment Scale of the Nursing Work Index (PES-NWI; Lake, 2002) in the Colombian clinical context. An instrument validation study using expert panel review, content validity indexing techniques, and a factor analysis of survey responses from 144 nurses was used. The scale-level content validity evaluation achieved high levels of acceptability, with values above 0.90. Construct validity results suggest that the instrument consists of 5 factors as prescribed by original instrument. The overall internal consistency value was a Cronbach's alpha level of 0.89. This is the first instrument to measure the work environment of nursing practice in South America, now validated in the Colombian context.

Nanopores can be used to detect and analyse biomolecules. However, controlling the translocation speed of molecules through a pore is difficult, which limits the wider application of these sensors. Here, we show that low-power visible light can be used to control surface charge in solid-state nanopores and can influence the translocation dynamics of DNA and proteins. We find that laser light precisely focused at a nanopore can induce reversible negative surface charge densities as high as 1 C m(-2), and that the effect is tunable on submillisecond timescales by adjusting the photon density. By modulating the surface charge, we can control the amount of electroosmotic flow through the nanopore, which affects the speed of translocating biomolecules. In particular, a few milliwatts of green light can reduce the translocation speed of double-stranded DNA by more than an order of magnitude and the translocation speed of small globular proteins such as ubiquitin by more than two orders of magnitude. The laser light can also be used to unclog blocked pores. Finally, we discuss a mechanism to account for the observed optoelectronic phenomenon.