Boar ejaculates are ejected in fractions with a specific composition in terms of sperm numbers and seminal plasma (SP), which is reflected in the varying sperm cryotolerance observed among different fractions. As boar sperm are particularly sensitive to oxidative stress, this study evaluated the role of SP antioxidants in the observed differences in sperm cryotolerance among ejaculate fractions. Ten ejaculates from five boars were manually collected in fractions: the first 10 mL of the sperm-rich fraction (SRF), the rest of the SRF and the post-SRF. Semen samples comprising the entire ejaculate (EE) were created by proportionally mixing the three fractions described above. Each of the 40 resulting semen samples was split into two aliquots: one was used for sperm cryopreservation following a standard protocol utilizing 0.5-mL straws, and the other was used to collect SP for antioxidant assessment. Frozen-thawed (FT) sperm from the SRF (the first 10 mL of the SRF and the rest of the SRF) and those from post-SRF were of the highest and worst quality, respectively, which was measured in terms of total and objective progressive motility and viability (P < 0.01). Viable FT sperm from the post-SRF generated more reactive oxygen species and experienced more lipid peroxidation than those from the SRF (both the first 10 mL and the rest of the SRF) (P < 0.01). The percentage of FT sperm exhibiting fragmented nuclear DNA did not differ among ejaculate fractions and the EE. Catalase, glutathione peroxidase and glutathione peroxidase 5 (GPx-5) were lowest in SP from the first 10 mL of the SRF (P < 0.001), whereas superoxide dismutase (SOD) and paraoxonase 1 (PON-1) were highest in SP of the SRF (both the first 10 mL and the rest of the SRF) (P < 0.01). Trolox-equivalent antioxidant capacity (TEAC) and the ferric-reducing ability of plasma (FRAP) were highest in SP from the first 10 mL of the SRF and lowest in the post-SRF (P < 0.001), whereas cupric-reducing antioxidant capacity was lowest (P < 0.05) in SP from the first 10 mL of the SRF. Regression analyses indicated that certain SP antioxidants had good predictive value for post-thaw recovery rates of total motility (R = 54.8%, P < 0.001; including SOD, TEAC and FRAP) and viability (R = 56.1%, P < 0.001; including SOD, PON-1, GPx-5 and TEAC). These results demonstrated that certain SP antioxidants are positively involved in boar sperm cryotolerance, minimizing the oxidative stress imposed by cryogenic handling.

Perfiles motivacionales de apoyo a la autonomía, autodeterminación, satisfacción, importancia de la educación física e intención de práctica física en tiempo libre Motivational profiles of autonomy support, self-determination, satisfaction, importance of physical education and intention to partake in leisure time physical activity Perfiles motivacionais de apoio à autonomia, auto-determinação, satisfação, importância da educação física e intenção de prática física no tempo livre

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ISCARE (Information System for Competition based on pRoblem solving in Education) is a new and inno-vative intelligent tutoring system that we have designed and implemented. This tool allows the compe-tition among students for improving their learning process in a course. The tool takes some ideas from the Swiss-system widely used in chess and adapts them to the educational area. The competition is based on different tournaments and rounds. In each round, students are assigned in pairs of two, which compete one against another, and each pair receives different questions that students have to solve in a limit of time. Students can see their partial ratings after each round and their final rating after a tournament. A lot of knowledge from different disciplines was used to design, and implement this system, as ISCARE includes different functionality such as the students' registration into the system, the creation of tourna-ments, the registration and assignment of students to tournaments, the management of each tournament life cycle (started, in execution, finished, etc.), the addition of the different exercises to tournaments, the calculation of pairs of students for each round with different algorithms, the assignment of exercises per round and pair, the scorings of the students per round and tournament, the management of the students' ratings, or the visualization of information. This paper presents the ISCARE intelligent tutoring system, describing its different options, menus, or functionality as well as its architecture and the specific mod-eling to achieve the desired features.