Natural disasters and university enrolment: Evidence from L’Aquila earthquake

Although there are several studies looking at the effect of natural disasters on economic growth, less attention has been dedicated to their impact on educational outcomes, especially in more developed countries. We use the synthetic control method to examine how the L’Aquila earthquake affected subsequent enrolment at the local university. This issue has wide economic implications as the University of L’Aquila made a large contribution to the local economy before the earthquake. Our results indicate that the earthquake had no statistically significant effect on first-year enrolment at the University of L’Aquila in the three academic years after the disaster. This natural disaster, however, caused a compositional change in the first-year student population, with a substantial increase in the number of students aged 21 or above. This is likely to have been driven by post-disaster measures adopted in order to mitigate the expected negative effects on enrolment triggered by the earthquake.

The signalling effect of eco-labels in modern coastal tourism

As the demand for environmentally sustainable tourism grows, eco-labels are becoming increasingly popular as a signal of environmental quality. However, the existence of a causal link between awarding a seaside eco-label and the increase in tourism flows is still under discussion in the literature. In this article, we gauge the signalling impact of a specific eco-label, the Blue Flag award, using detailed data on tourism flows to seaside Italian destinations during the period 2008-2012. We adopt a recent econometric modelling strategy - the synthetic control method - in shaping estimation results and testing the sensitivity and robustness of our results. We find that being awarded the Blue Flag increases the flow of domestic tourists for up to three seasons after assignment. However, we find no effect for the flow of international tourists. Investigating the mechanisms driving the results, we find that the award of a Blue Flag only positively affects the flow of domestic tourists when it is used as a driver of organisation, coordination and integrated management of the tourism supply.

A thin-layer chromatography-bioautographic method for detecting dipeptidyl peptidase IV inhibitors in plants

A thin-layer chromatography (TLC)-bioautographic method was developed with the aim to detect dipeptidyl peptidase IV (DPP IV) inhibitors from plant extracts. The basic principle of the method is that the enzyme (DPP IV) hydrolyzes substrate (Gly-Pro-p-nitroaniline) into p-nitroaniline (pNA), which diazotizes with sodium nitrite, and then reacts with N-(1-naphthyl) ethylenediamine dihydrochloride in turn to form a rose-red azo dye which provides a rose-red background on the TLC plates. The DPP IV inhibitors showed white spots on the background as they blocked enzymolysis of the substrate to produce pNA. The method was validated with respect to selectivity, sensitivity, linearity, precision, recovery, and stability after optimizing key parameters including plate type, time and temperature of incubation, concentration of substrate, enzyme and derivatization reagents, and absorption wavelength. The results showed good lineary within amounts over 0.01–0.1 μg range for the positive control, diprotin A, with the coefficient of determination (r2) = 0.9668. The limits of detection (LOD) and quantification (LOQ) were 5 and 10 ng, respectively. The recoveries ranged from 98.9% to 107.5%. The averages of the intra- and inter-plate reproducibility were in the range of 4.1–9.7% and 7.6–14.7%, respectively. Among the nine methanolic extracts of medicinal herbs screened for DPP IV inhibitors by the newly developed method, Peganum nigellastrum Bunge was found to have one white active spot, which was then isolated and identified as harmine. By spectrophotometric method, harmine hydrochloride was found to have DPP-IV inhibitory activity of 32.4% at 10 mM comparing to that of 54.8% at 50 μM for diprotin A.