Delayed preconditioning-mimetic actions of exercise or nitroglycerin do not affect haemodynamics and exercise performance in trained or sedentary individuals

Nitroglycerin induces the so-called second window of protection (SWOP), which alleviates myocardial damage and stunning after ischaemia/reperfusion. To determine whether myocardial performance during exercise is improved in the second window of protection, we studied the haemodynamic responses of 12 trained and 11 sedentary individuals during a sequence of maximal tests on a cycle ergometer. A baseline test (basal test) was followed by a second effort performed during the second window of protection (exercise-SWOP test). Haemodynamics was also evaluated after pharmacologically induced SWOP 48 h after transdermal administration of 10 mg of nitroglycerin (pharmacologically induced SWOP test). The exercise-SWOP and pharmacologically induced SWOP tests were separated by a 1-week washout period. Endothelial-dependent vasodilatation after nitroglycerin pre-treatment was also assessed in five sedentary individuals to determine whether nitrate donors could affect vascular function. We found that nitroglycerin pre-treatment did not induce any improvement in haemodynamics in either trained or sedentary individuals, since maximum values of workload, heart rate, stroke volume, cardiac output, myocardial contractility, and double product were similar between the exercise-SWOP and pharmacologically induced SWOP tests in both groups. Furthermore, nitroglycerin pre-treatment did not alter flow-mediated dilation during pharmacologically induced SWOP. Although nitroglycerin pre-treatment alleviates post-ischaemic myocardial stunning, our results suggest that it does not affect the myocardial performance of healthy individuals during exercise performed in the second window of protection, independently of the training status of the individuals. Moreover, nitroglycerin pre-treatment does not ameliorate endothelial function.     

A new class of gels for the conservation of painted surfaces

The application of a new class of organogels as cleaning tools for painted surfaces is described. It combines some of the most attractive features of cleaning liquids and normal gels while diminishing the deleterious characteristics of both. Thus, the ‘latent’ gellant, polyethyleneimine (PEI), reacts with CO₂ at room temperature in solutions of several organic liquids to produce an ammonium carbamate form (PEICO₂). This charged species organizes itself into 3D polymer networks which immobilize the liquids as gels. The properties of the original solution (i.e. a free-flowing liquid) are re-established immediately after addition of a small amount of a weak acid which displaces the CO₂ molecules and makes the PEI chains positively charged. The visual changes are substantiated by rheological analyses. Results from analytical tests to determine the utility of these gels as cleaning tools for painted surfaces of historical and artistic interest, have been obtained from contact angle and FTIR measurements as well as visual comparisons of the surfaces before and after application of the gels. The analyses indicate that the PEICO₂-based organogels were very effective in removing different surface patinas from painted supports. A surface layer of dammar was completely removed from a test canvas with oil paint, an aged painting from the XIX century, and a XV century oil-on-wood panel attributed to Mariotto di Cristoforo. Finally, a surface acrylic polymeric resin (used in a restoration performed during the 1960s) was also successfully removed from Renaissance wall paintings decorating the Santa Maria della Scala Sacristy in Siena, Italy. The isothermally rheoreversible gel approach described in this work represents a new, highly versatile, and very efficient method for removing aged surface patinas from works of art.     

Bidirectional avoidance by mice as a function of CS,US, and apparatus variables

Acquisition of two-way avoidance by mice was slower with a light CS than with a buzzer CS, with punishment of intertrial responses than without punishment, and with a short CS-CS interval than with a long CS-CS interval (30 vs. 60 sec). Light-cued avoidance was little affected by shock level (.35–1.5 mA), whereas mice trained with the buzzer CS learned faster at 1.5 mA. Animals required to move away from light or toward light showed comparable rates of acquisition. Other CS, US, and apparatus variables (directionality of cue, maximal shock duration, and presence vs. absence of a central partition in the shuttlebox) interacted in a complex fashion with those already mentioned. This resulted in widely differing performances in what may superficially appear to be different versions of the same task. The differences in mouse and rat responses to some of the variables can contribute to an understanding of the interactions between organismic and test factors and the relative explanatory value of alternative avoidance models.     

Knowledge space oddity: How to increase the intensity and relevance of the technological progress of European regions

This work contributes to previous research on the relationship between specific features of a regional knowledge space and the technological progress of the region. In particular, the main element of originality of this work is to have singled out the determinants of the technological progress intensity and relevance. We acknowledge the importance of knowledge assets for new knowledge production, and we identify path-dependent processes that allow a region to become increasingly competitive in terms of innovation potential. In particular, adopting an evolutionary view of regional development, we describe the regional knowledge space through four crucial characteristics: 1) technological knowledge base, 2) technological cumulativeness, 3) technological diversification, and 4) technological relatedness. We then measure to what extent each of the knowledge space’s characteristics differently affects the technological progress intensity and relevance of the region. A longitudinal study of 269 European regions over the period 1996–2012 was organized using data from REGPAT and Eurostat databases. Results show that technological relatedness affects positively both the intensity and relevance of the technological progress of European regions and that the other components of the knowledge space show a different impact on the two features of the technological progress. Finally, implications for EU policies supporting and stimulating regional technological progress are discussed.     

Additive benefits of external focus and enhanced performance expectancy for motor learning

The authors examined the individual and combined influences of 2 factors that have been shown to benefit motor learning: an external focus of attention and enhanced performance expectancies. Another purpose of this study was to gain further insight into the mechanisms underlying these variables. In a factorial design, participants learning a novel motor skill (i.e., throwing with the non-dominant arm) were or were not given external focus instructions, and were or were not provided bogus positive social-comparative feedback to enhance their expectancies. This resulted in 4 groups: external focus, enhanced expectancy, external focus/enhanced expectancy and control. External focus instructions and enhanced expectancies had additive benefits for learning: the external focus/enhanced expectancy group demonstrated the greatest throwing accuracy on both retention and transfer tests, while the accuracy scores of the external focus and enhanced expectancy groups were lower, but higher than those of the control group. Furthermore, self-efficacy was increased by both external focus and enhanced expectancy, and predicted retention and transfer performance. Positive affect was heightened in the enhanced expectancy and external focus/enhanced expectancy groups after practice and predicted transfer performance. The findings suggest that the learning benefits of an external focus and enhanced expectancies mediate learning through partially different mechanisms.     

Consensus-based course design and implementation of constructive alignment theory in a power system analysis course

This article presents the implementation of the constructive alignment theory (CAT) in a power system analysis course through a consensus-based course design process. The consensus-based design process involves both the instructor and graduate-level students and it aims to develop the CAT framework in a holistic manner with the goal of including different perceptions. The considerations required to implement this approach are described in detail. To examine the effect of this approach, three different course evaluations were conducted by querying the students during different stages of the course. These evaluations show that most of the students find a benefit for their learning in the implementation of CAT within the new course design. These observations are supported by a comparison of the students’ performance in the new course and the previous one. Finally, the revised two-factor study process questionnaire (R-SPQ-2F) is utilised to identify the students’ learning approach towards the course. The aim is to correlate the students’ approach with their final grade to assess if students adopting a deep learning approach are rewarded with higher marks and vice versa, that is, to check if the CAT implementation was successful. Meanwhile, some of the R-SPQ-2F limitations, which affect the quality of the results, are identified and discussed. Additionally, to facilitate the practical usage of R-SPQ-2F, an algorithm was developed by the authors to rank the students’ approach towards the course. The results of the new ranking algorithm demonstrate positive correlation with the students’ final grade, which is an indication of the effective CAT implementation.