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For the practical application of dye-sensitized solar cells (DSSCs), it is important to replace the conventional organic solvents based electrolyte with environmentally friendly and stable ones, due to the toxicity and leakage problems. Here we report a noble water-based thixotropic polymer gel electrolyte containing xanthan gum, which satisfies both the environmentally friendliness and stability against leakage and water intrusion. For application in DSSCs, it was possible to infiltrate the prepared electrolyte into the mesoporous TiO2 electrode at the fluidic state, resulting in sufficient penetration. As a result, this electrolyte exhibited similar conversion efficiency (4.78% at 100 mW cm(-2)) and an enhanced long-term stability compared to a water-based liquid electrolyte. The effects of water on the photovoltaic properties were examined elaborately from the cyclic voltammetry curves and impedance spectra. Despite the positive shift in the conduction band potential of the TiO2 electrode, the open-circuit voltage was enhanced by addition of water in the electrolyte due to the greater positive shift in the I(-)/I3(-) redox potential. However, due to the dye desorption and decreased diffusion coefficient caused by the water content, the short-circuit photocurrent density was reduced. These results will provide great insight into the development of efficient and stable water-based electrolytes.

BackgroundHand hygiene compliance has improved significantly through hand hygiene promotion programs that have included poster campaign, monitoring and performance feedback, and education with special attentions to perceived subjective norms. We investigated factors associated with improved hand hygiene compliance, focusing on whether the improvement of hand hygiene compliance is associated with changed perception toward hand hygiene among medical personnel.Materials and MethodsHand hygiene compliance and perceptions toward hand hygiene among medical personnel were compared between the second quarter of 2009 (before the start of a hand hygiene promotion program) and the second quarter of 2012. We assessed adherence to hand hygiene among medical personnel quarterly according to the WHO recommended method for direct observation. Also, we used a modified self-report questionnaire to collect perception data.ResultsHand hygiene compliance among physicians and nurses improved significantly from 19.0% in 2009 to 74.5% in 2012 (P < 0001), and from 52.3% to 91.2% (P < 0.001), respectively. These improvements were observed in all professional status or all medical specialties that were compared between two periods, regardless of the level of the risk for cross-transmission. Hand hygiene compliance among the medical personnel continued to improve, with a slight decline in 2013. Perceptions toward hand hygiene improved significantly between 2009 and 2012. Specifically, improvements were evident in intention to adhere to hand hygiene, knowledge about hand hygiene methods, knowledge about hand hygiene indications including care of a dirty and a clean body site on the same patient, perceived behavioral and subjective norms, positive attitude toward hand hygiene promotion campaign, perception of difficulty in adhering to hand hygiene, and motivation to improve adherence to hand hygiene.ConclusionsThe examined hand hygiene promotion program resulted in improved hand hygiene compliance and perception toward hand hygiene among medical personnel. The improved perception increased hand hygiene compliance. Especially, the perception of being a role model for other colleagues is very important to improve hand hygiene compliance among clinicians.

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