Automatic prebent customized prosthesis for pectus excavatum minimally invasive surgery correction

Pectus excavatum is the most common deformity of the thorax. A minimally invasive surgical correction is commonly carried out to remodel the anterior chest wall by using an intrathoracic convex prosthesis in the substernal position. The process of prosthesis modeling and bending still remains an area of improvement. The authors developed a new system, i3DExcavatum, which can automatically model and bend the bar preoperatively based on a thoracic CT scan. This article presents a comparison between automatic and manual bending. The i3DExcavatum was used to personalize prostheses for 41 patients who underwent pectus excavatum surgical correction between 2007 and 2012. Regarding the anatomical variations, the soft-tissue thicknesses external to the ribs show that both symmetric and asymmetric patients always have asymmetric variations, by comparing the patients’ sides. It highlighted that the prosthesis bar should be modeled according to each patient’s rib positions and dimensions. The average differences between the skin and costal line curvature lengths were 84 ± 4 mm and 96 ± 11 mm, for male and female patients, respectively. On the other hand, the i3DExcavatum ensured a smooth curvature of the surgical prosthesis and was capable of predicting and simulating a virtual shape and size of the bar for asymmetric and symmetric patients. In conclusion, the i3DExcavatum allows preoperative personalization according to the thoracic morphology of each patient. It reduces surgery time and minimizes the margin error introduced by the manually bent bar, which only uses a template that copies the chest wall curvature.

Style and performance of international socially responsible funds in Europe

This paper analyses the performance and investment styles of internationally oriented Socially Responsible Investment (SRI)funds, domiciled in eight European markets, in comparison with characteristics-matched conventional funds. To the best of our knowledge, this is the first multi-country study, focused on international SRI funds (investing in Global and in European equities), to combine the matched-pairs approach with the use of robust conditional multi-factor performance evaluation models, which allow for both time-varying alphas and betas and also control for home biases and spurious regression biases.In general, the results show that differences in the performance of international SRI funds and their conventional peers are not statistically significant. Regarding investment styles, SRI and conventional funds exhibit similar factor exposures in most cases. In addition,conventional benchmarks present a higher explaining power of SRI fund returns than SRI benchmarks. Our results also show significant differences in the investment styles of SRI funds according to whether they use “best-in-class” screening strategies or not. When compared to SRI funds that employ simple negative and/or positive screens, SRI “best-in-class” funds present significantly lower exposures to small caps and momentum strategies and significantly higher exposures to local stocks.

Selectivity and timing abilities of international socially responsible funds

This article analyses the selectivity and market timing abilities of international Socially Responsible Investment (SRI) funds, from eight European markets, in comparison to conventional funds with similar characteristics. The results show that differences in market timing abilities of international SRI funds and their conventional peers are not statistically significant. However, SRI funds investing in European equities are significantly worse stock pickers than conventional funds, whereas for funds investing globally, selectivity abilities are similar among both fund groups. Hence, our results suggest that a broader investment universe might increase SRI fund managers’ stock picking abilities and, consequently, improve SRI fund performance.

Performance of european socially responsible funds during market crises: evidence from France

This paper investigates the performance, investment styles andmanagerial abilities of French socially responsible investment (SRI) funds investing in Europe during crisis and non-crisis periods. Our results show that SRI funds significantly underperformcharacteristics-matched conventional funds during non-crisis periods, but match the performance of their peers duringmarket downturns. The underperformance of SRI funds during good economic states is driven by funds that use negative screens, since funds that use only positive screens performsimilarly to conventional funds across differentmarket conditions. SRI and conventional funds showsignificant differences in risk exposures during non-crisis periods but exhibit much more similar investment styles during crises. Furthermore,we find little evidence of significant differences inmanagerial abilities during bad economic states. Yet, during non-crisis periods, SRI and conventional fund managers exhibit significantly different style-timing abilities and these differences are also related to screening strategies.