World-class long- distance running performances are best predicted by volume of easy runs and deliberate practice of short interval and tempo runs

The aim of this novel study was to analyze the effect of deliberate practice (DP) and easy runs completed by elite-standard and world-class long-distance runners on competitive performances during the first 7 years of their sport careers. Eighty-five male runners reported their best times in different running events and the amounts of different DP activities (tempo runs and short and long interval sessions) and 1 non-DP activity (easy continuous runs) after 3, 5 and 7 years of systematic training. Pearson’s correlations were calculated between performances (calculated using the IAAF scoring tables) and the distances run for the different activities (and overall total). Simple and Multiple Linear Regression Analysis calculated how well these activities predicted performance. Pearson’s correlations showed consistently large effects on performance of total distance (r ≥ 0.75, P < 0.001), easy runs (r ≥ 0.68, P < 0.001), tempo runs (r ≥ 0.50, P < 0.001) and short interval training (r ≥ 0.53, P < 0.001). Long interval training was not strongly correlated (r ≥ 0.22). Total distance accounted for significant variance in performance (R2 ≥ 0.57, P < 0.001). Of the training modes, Hierarchical Regression Analysis showed that easy runs and tempo runs were the activities that accounted for significant variance in performance (P < 0.01). Although DP activities, particularly tempo runs and short interval training, are important for improving performance, coaches should note that the non-DP activity of easy running was crucial in better performances, partly because of its contribution to total distance run

Personalities in female domesticated pigs: behavioural and physiological indications

The inconclusive evidence so far on the existence of distinct personality types in domesticated pigs, led us to perform the present experiment. A total of 128 gilts from 31 sows were systematically studied from birth to slaughter in two identical trials. Intra-test consistency in individual behavioural andror physiological reactions was studied in three different tests. We were not able to show consistencies in reactions of gilts over time to a backtest (at 2–4 days and 4 weeks of age) and to a novel environment test (at 10 and 24 weeks of age). Individual aggression, however, as measured in a group-feeding competition test in stable groups (at 10 and 24 weeks of age), proved to be highly consistent. Explanations for these discrepancies in intra-test consistencies are critically discussed. Inter-test consistencies were determined by relating the individual reactions of gilts to the backtest to various characteristics and responses to tests at a later age. The highest correlations were found when resistance in the first backtest was involved. No evidence was found for the existence of specific isolated categories of animals with respect to this resistance. For further analysis, extreme responding gilts in the first backtest (roughly the top and bottom 25% of the distribution) were classified as low resistant (LR; <3 escape attempts; n=31) or high resistant (HR; >4 escape attempts; n=45). By comparisons of mean responses of LR and HR gilts within groups, we have established a relationship between the backtest and several other variables. Behaviourally, the HR gilts showed more aggression in the group-feeding competition tests. Also, in the competition for the most productive teats at the anterior, a predominant position of HR piglets at this site was observed during the suckling period. The latter piglets also gained more weight during this period than LR ones. Compared to HR pigs, in the first novel environment test LR pigs hesitated longer to leave their home pens and to contact a human, but no difference in their locomotory behaviour was observed. Contrasts between LR and HR pigs in the second novel environment test were reduced or absent. Physiologically, when compared to HR gilts, LR ones had a higher reactivity of the hypothalamic–pituitary–adrenocortical (HPA) system. This was shown by higher cortisol responses to the first novel environment test, to routine weighing at 25 weeks of age, and to administration of a high dose of ACTH. It is discussed that these findings for LR and HR gilts, may provide support for the existence of behavioural and physiological responses in pigs, resembling those of proactive and reactive rodents.

Teaching and Assessing Engineering Design Thinking with Virtual Internships and Epistemic Network Analysis

An engineering workforce of sufficient size and quality is essential for addressing significant global challenges such as climate change, world hunger, and energy demand. Future generations of engineers will need to identify challenging issues and design innovative solutions. To prepare young people to solve big and increasingly global problems, researchers and educators need to understand how we can best educate young people to use engineering design thinking. In this paper, we explore virtual internships, online simulations of 21st-century engineering design practice, as one method for teaching engineering design thinking. To assess the engineering design thinking, we use epistemic network analysis (ENA), a tool for measuring complex thinking as it develops over time based on discourse analysis. The combination of virtual internships and ENA provides opportunities for students to engage in authentic engineering design, potentially receive concurrent feedback on their engineering design thinking, and develop the identity, values, and ways of thinking of professional engineers

Behavioural and physiological consequences of acute social defeat in growing gilts: effects of the social environment

Endocrine, behavioural and immunologic processes, together with body growth, were evaluated in gilts that were defeated at 10 weeks of age in resident-intruder tests. Immediately after defeat, gilts were either separated from or reunited with a familiar conspecific (litter-mate; always a barrow). Gilts were assigned to one of four treatments: (a) DI: defeat, followed by isolation (separation from original litter-mate; n=8); (b) I: no defeat, isolation (control group; n=9); (c) DP; defeat, followed by pair-housing (reunion with original litter-mate; n=8); and (d) P: no defeat, pair-housing (control group; n=8). The following general conclusions were derived: (1) social defeat caused pronounced short-term elevations in hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal medullary activities, and of prolactin levels. Moreover, as soon as 1 h after defeat, percentages of blood lymphocytes and neutrophilic granulocytes were, respectively, decreased and increased; (2) social defeat had some long-lasting influence on behaviour and physiology, but isolation predominantly determined responses in the longer term. Defeat, as well as isolation, resulted in increased cardiovascular activities compared to P controls, as observed in a novel object test (NOT: +7 days) and an aversion test (AVT: +14 days). Moreover, defeated as well as isolated gilts did not habituate to a repeated novel environment test (NET: -7, +2 and +7 days) in terms of frequencies of vocalising, whereas P controls did. Isolation, through the separation from any other pig, was responsible for the other observed long-term characteristics, which developed progressively. Isolated gilts showed high mobilities and high cortisol responses in the repeated NET (+7 days), not being habituated. This contrasted the reactions of pair-housed gilts, which were much reduced. In addition to their high cardiovascular activities in the NOT and the AVT, isolated gilts also displayed higher heart rates in the repeated NET and during human presence following the NOT, compared to pair-housed gilts. Finally, isolated gilts were more inhibited to approach a novel object (in the NOT) than pair-housed pigs; and (3) stress responses of defeated gilts were modulated by the subsequent social environment. Stimulation of the HPA-axis (plasma- and salivary cortisol) was prolonged in those defeated gilts which were isolated (observed in the first hour). Changes in leucocyte subsets were still observed after 3 days in DI, but were `normalised' within 1 day in DP gilts. Two days after defeat, habituation to the repeated NET in terms of mobility and salivary cortisol responses occurred in control and DP gilts, but not in DI gilts. We argue that these effects of the social environment shortly after defeat were related to a stress-reducing effect of a stable social relationship, i.e. social support.

Sister chromatid telomere fusions, but not NHEJ-mediated inter-chromosomal telomere fusions, occur independently of DNA ligases 3 and 4

Telomeres shorten with each cell division and can ultimately become substrates for non-homologous end-joining repair, leading to large-scale genomic rearrangements of the kind frequently observed in human cancers. We have characterised over 1400 telomere fusion events at the single-molecule level, using a combination of high-throughput sequence analysis together with experimentally-induced telomeric double-stranded DNA breaks. We show that a single chromosomal dysfunctional telomere can fuse with diverse non-telomeric genomic loci, even in the presence of an otherwise stable genome, and that fusion predominates in coding regions. Fusion frequency was markedly increased in the absence of TP53 checkpoint control and significantly modulated by the cellular capacity for classical, versus alternative, non-homologous end joining (NHEJ). We observed a striking reduction in inter-chromosomal fusion events in cells lacking DNA ligase 4, in contrast to a remarkably consistent profile of intra-chromosomal fusion in the context of multiple genetic knockouts, including DNA ligase 3 and 4 double-knockouts. We reveal distinct mutational signatures associated with classical NHEJ-mediated inter-chromosomal, as opposed to alternative NHEJ-mediated intra-chromosomal telomere fusions and evidence an unanticipated sufficiency of DNA ligase 1 for these intra-chromosomal events. Our findings have implications for mechanisms driving cancer genome evolution

Bedrijfsplan high-techbedrijf

Het high-techbedrijf heeft als doelstelling: Realisatie van een lage kostprjis per kg melk (75 cent) via een hoge productiviteit per ha en per manuur; bij een goede diergezondheid en dierwelzijn, waarbij voldaan wordt aan de eindnormen van Minas

Cover crop planting practices determine their performance in the U.S. Corn Belt

Cover crop growing periods in the western U.S. Corn Belt could be extended by planting earlier. We evaluated both pre-harvest broadcast interseeding and post-harvest drilling of the following cover crops: (a) cereal rye (Secale cereale L.) [RYE]; (b) a mix of rye + legumes + brassicas [MIX1], (c) a mix of rye + oat [Avena sativa L.] + legumes + brassicas (MIX2), (d) legumes [LEGU]) and (e) a no cover crop control. These were tested in continuous corn (Zea mays L.) [corn–corn] and soybean [Glycine max (L.) Merr.]–corn systems [soybean–corn] at three sites in Nebraska for their effect on cover crop productivity, soil nutrients, and subsequent corn performance. At the sites with wet fall weather, pre-harvest broadcasting increased cover crop biomass by 90%, to 1.29 Mg ha−1 for RYE and 0.87 Mg ha−1 for MIX1 in soybean–corn, and to 0.56 Mg ha−1 and 0.39 Mg ha−1 in corn–corn, respectively. At the drier site, post-harvest drilling increased biomass of RYE and MIX1 by 95% to 0.80 Mg ha−1 in soybean–corn. Biomass N uptake was highest in pre-harvest RYE and MIX1 at two sites in soybean–corn (35 kg ha−1). RYE and sometimes mixes reduced soil N, but effects on P, K, and soil organic C were inconsistent. In soybean–corn, corn yields decreased by 4% after RYE, and in corn–corn, by 4% after pre-harvest cover crops. Site-specific selection of cover crops and planting practices can increase their performance while minimizing impacts on corn