Effect of the Condensation of Hybrid Organic–Inorganic sol–gel Materials on the Optical Properties of Tripan Blue

The work reported in this paper highlights the effect of sol–gel structures on the optical properties of a typical organic dye (Trypan Blue, TB). Three transition-metal-based hybrid sol–gel materials with different structures and morphologies were developed and characterised by TEM. The optical properties of TB were investigated by incorporating it in the different sol–gel materials and the UV–Visible spectra recorded in both liquid and solid state, in thin-coatings cured at temperatures in the range 100– 150 [1]C. These studies revealed two relevant results. First, the sol–gel morphology plays a critical role in the optical properties of the dye. The effect of the sol–gel host matrix on the optical properties of the dye is attributed to the steric hindrance of the nanostructures, themselves intimately dependant on the reactivity of the transition metal. For instance, the less condensed system showed the highest reactivity with the dye, while the more condensed system exhibited limited interaction with the dye, symbolised by a significant change or quasi-unchanged UV–Visible spectra, respectively. It is also shown that the increase of the condensation degree of the sol–gel coatings by heat-curing can dramatically alter the optical properties of the dye especially for the most condensed sol–gel systems. This has been attributed to proximity effects enabled by the further increase of the materials densities. The results reported here aim to provide a better understanding of how material formulations can influence the optical properties of organic dyes and suggest that the structure of the host matrix along with the applied curing process have to be fully considered and assessed in the choice of organic dyes for a given application

Coaching Elementary Teachers in Literacy: Does Feedback Type Matter for Low Implementers?

For literacy coaches and teachers, feedback is an integral component of effective coaching. Yet, little is understood about the interaction between feedback and high/low implementing teachers within coaching sessions. This multiple case study explored the types of feedback literacy coaches provided both high and low implementing teachers over a two-year period. In the first year, the literacy coaches provided at least twice as much instructional feedback as emotional feedback to low-implementing teachers. Those teachers not only received more feedback in general, but the feedback they received was primarily what they needed to do to improve. In contrast, during the same period literacy coaches provided high-implementing teachers more emotional feedback than instructional feedback. Low implementation, or resistance, observed in this study may have been tied to the overwhelming amount and type of feedback the low implementing teachers received.  Coaches seeking to enhance instructional practices could benefit from attending to the amount and type of feedback they provide their learners.

Respiratory illness in children: Do deprived children have worse coughs?

Parents of a stratified random sample of 234 children from 21 general practices in North East England were interviewed at home. All these children had been reported in a postal questionnaire as having had a cough between six and ten weeks before the interview. Interviews covered social characteristics of the family, the severity of the child's cough and the reactions of the parents to hypothetical sets of symptoms. The parents of children in materially deprived circumstances appeared to report worse coughs than other parents. We confirmed this finding by constructing a scale of perceived cough severity. However, we found no evidence that the inequality was due to exaggeration of the severity of the cough by materially deprived parents. Our conclusion that materially deprived children suffer worse respiratory illness is the more important because previous evidence suggets that the after-effects persist into adulthood