Four untrained standardbred horses performed a standardized exercise test on the treadmill and an automated blood collection system programmed to obtain blood samples every 15 s was used for blood collection in order to evaluate the kinetics of adrenaline and noradrenaline. The highest average values obtained for adrenaline and noradrenaline were 15.0 +/- 3.0 and 15.8 +/- 2.8 nmol/l respectively, with exponential accumulation of adrenaline (r = 0.977) and noradrenaline (r = 0.976) during the test. Analysis of the correlation between noradrenaline and adrenaline for each phase of the test shows that correlation coefficient decreases as the intensity of exercise increases (from r = 0.909 to r = 0.788). This suggests that during submaximal exercise, the process for release, distribution and clearance of adrenaline into blood circulation differs from that of noradrenaline.

The present research compares the results obtained by using two different methods of instruction in teaching Darwin's evolution theory: laboratory activities and traditional lessons based on textbooks. We built up a teaching path on evolution using laboratory activities, to highlight how the main concepts of this theory (selection, adaptation, variability, inheritance, case, time) can be handled also by doing, interacting, and cooperating, in other words by "putting students' thinking into action". This path does not refer to a real scientific laboratory (meaning a physical space with materials and instruments) but to an educational laboratory, "poor" and characterised by limited time activities. Widening the definition of laboratory allows teachers to create active and informal learning contexts, exploiting educational resources supplied by those centres which promote both culture and knowledge, as well as by specific events organized in the scientific network. Every activity has been planned to explain one or more of the main themes, using the following methods: economy of ideas, logical consistency, introductory value, and scientific accuracy. The experimental groups were third-year students attending secondary school. A questionnaire was used before and after the course, to assess students' acceptance and understanding of evolution. With both methods results highlighted relevant differences in understanding concepts, in religious-based questions and scientific facts regarding evolution. Moreover, the comparison of answers obtained using either the traditional or the laboratory method shows several differences. In particular, the percentage of students accepting and understanding the evolution theory is much higher in those who participated in laboratory lessons. In conclusion, it can be assumed that, in teaching evolution, lessons proposing scientific experiments through active and practical activities are much more effective than lessons based on school books and frontal methods. Thus, a teaching path based on interaction and cooperation of students in a scientific laboratory is to be considered more successful.

Antarctica is the continent with the lowest local human impact, yet it is still vulnerable to contaminants coming from external sources. Emerging pollutants, like PFAS, pose an increasing threat to this environment and therefore require more in-depth investigations to understand their environmental fate and biological impacts. The present study, part of the AntaGPS project, focuses on expression analysis at the transcriptional level of genes coding for 4 antioxidant enzymes (sod1, sod2, gpx1, gpx4) in different organs of an Antarctic fish species, Trematomus newnesi. The kidney showed a higher level of expression than the liver of wildlife specimens. The mRNA levels were also assessed in fish exposed to 1.5 μg/L of PFOA for 10 days. In the liver, the treatment induced an increase in gene expression for all the considered enzymes, while in the kidney it induced a general decrease. The obtained results constitute a starting point for using the expression of antioxidant enzymes as biomarkers, both of oxidative stress and exposure to PFAS, in future biomonitoring campaigns in the Antarctic marine environment.

With a view to active learning, that makes the students protagonist, responsible and aware of the learning process, the present study presents an experimental work designed to demonstrate the usefulness and validity of the scientific method as the basic element of teaching Life Sciences. The experimental research was implemented in two second-grade classes at a Primary School in San Donà di Piave (Italy). Its purpose was to test the potency of a teaching approach based on the scientific method, particularly the observationalcomparative method, in the teaching of Life Sciences, focused on the structure of the flower and the inflorescences. For this reason, it was decided that one of the two classes used the experimental method instead of a traditional teaching-learning method based on the oral transmission of contents. During the action, students were invited to use scientific tools in each lesson as magnifiers, stereoscopes, and specimens of flowers. Active teaching and direct observation of flower structures reinforced the concepts theoretically exposed. This way, the high teaching potential of integrating macroscopic and microscopic observations was also confirmed. The observational-comparative method is a key component of the study of Biology. For this reason, all the topics linked to the study of plants can be addressed through the use of this active methodology. This kind of approach can motivate students, making them active participants in their learning. The obtained results showed that using the scientific method and laboratory tools such as the optical microscope or the magnifiers, conceptualizations planned for fifth grade, can be met with success also in second grade, helping to reach the programmed goals optimally and often excellently, facilitating the achievement of competences such as the use of a correct scientific nomenclature. With this approach, the young students were motivated, stimulated, intrigued, and this potentially provides meaningful, authentic and transferable Lifelong Learning and the development of a scientific culture together with an early interest in the Sciences.

High levels of reactive oxygen species (ROS: superoxide, hydroxyl, hydrogen peroxide, nitric oxide, peroxynitrile) endanger sperm motility, viability, and function by interaction with membrane lipids, proteins, and nuclear and mitochondrial DNA (Sikka 2004 J. Androl. 25, 5–18). ROS generation has a significant negative effect on the fertilization rate after IVF, and so measurement of ROS levels in semen specimens before IVF may be useful in predicting the IVF outcome (Agarwal et al. 2005 Fertil. Steril. 84, 228–231). Several compounds of the antioxidant systems have been identified in the epididymal environment, spermatozoa, and seminal plasma. The antioxidants carnosine, L-histidine (Ducci et al. 2006 Pol. J. Vet. Sci. 9, 159–163), and taurine (Van der Horst and Grooten 1966 Biochim. Biophys. Acta. 117, 495–497) have been detected in boar semen and added to the extender in freezing procedures in several species. The main objective of this study was to evaluate the effect of carnosine, L-histidine, and taurine supplementation of the extender on boar sperm functionality as measured by sperm motility during computer-assisted semen analysis (CASA) and by IVF ability using mature oocytes, as previously described (Selles et al. 2003 Reprod. Domest. Anim. 38, 66–72). The sperm-rich fraction from mature fertile boars was diluted with isothermal Beltsville thawing solution (BTS) extender. Diluted semen was placed at 15�C and centrifuged at 800g for 10 min. The semen pellet was resuspended with BTS supplemented by 5 mm of carnosine, L-histidine, or taurine or not supplemented (control) to provide 75 � 106 spermatozoa mL–1 and stored at 15�C for 24 h (IVF assay), or 48 or 120 h (for CASA assay). We observed that the motility parameters were affected by storage time and that the addition of taurine increased the motility at 48 h of storage. Alternately, the addition of L-histidine to the extender reduced significantly the motility parameters after 120 h. The results showed that the addition of L-histidine induced a significant (P ≤ 0.01) decrease of the penetration rate (L-histidine 75.8% v. control 89.9%) and the number of sperm per oocyte penetrated (L-histidine 3.1 v. control 4.1). The rate of male pronuclear formation was not affected by the addition of antioxidants to the extender (over 85% in all cases). The addition of carnosine and taurine had no effect on the IVF parameters. In conclusion the antioxidants carnosine, taurine, and L-histidine affect sperm functionality differently, and further studies are necessary to elucidate what changes in sperm function take place during storage and the mechanisms by which these antioxidants exert their effects. This work was supported by Italian-Spanish research project HI2005-0165 and AGL2006-03495.