Caffeine increases peripheral fatigue in low- but not in high-performing cyclists

The influence of cyclists’ performance levels on caffeine-induced increases in neuromuscular fatigue after a 4-km cycling time trial (TT) was investigated. Nineteen cyclists performed a 4-km cycling TT 1 h after ingesting caffeine (5 mg·kg−1) or placebo (cellulose). Changes from baseline to after exercise in voluntary activation (VA) and potentiated 1 Hz force twitch (Qtw,pot) were used as markers of central and peripheral fatigue, respectively. Participants were classified as “high performing” (HP, n = 8) or “low performing” (LP, n = 8) in accordance with their performance in a placebo trial. Compared with placebo, caffeine increased the power, anaerobic mechanical power, and anaerobic work, reducing the time to complete the trial in both groups (p < 0.05). There was a group versus supplement and a group versus supplement versus trial interaction for Qtw,pot, in which the postexercise reduction was greater after caffeine compared with placebo in the LP group (Qtw,pot = −34% ± 17% vs. −21% ± 11%, p = 0.02) but not in the HP group (Qtw,pot = −22% ± 8% vs. −23% ± 10%, p = 0.64). There was no effect of caffeine on VA, but there was a group versus trial interaction with lower postexercise values in the LP group than in the HP group (p = 0.03). Caffeine-induced improvement in 4-km cycling TT performance seems to come at the expense of greater locomotor muscle fatigue in LP but not in HP cyclists. Novelty Caffeine improves exercise performance at the expense of a greater end-exercise peripheral fatigue in low-performing athletes. Caffeine-induced improvement in exercise performance does not affect end-exercise peripheral fatigue in high-performing athletes. High-performing athletes seem to have augmented tolerance to central fatigue during a high-intensity time trial.

Preference organization in PRC criminal trial interaction

This paper analyzes resistance in the preference organization of criminal trial interaction from a conversation analytic perspective, with examples taken from an 11-hour video corpus of 20 PRC (People’s Republic of China) criminal trials from 2016–2018. Defendants’ dispreferred responses to judges’ questions are then analyzed to determine how resistance is constructed and handled by judges. Defendants are found to construct resistance implicitly and orient to out-of-courtroom stance, objects and topics, while judges respond by reorienting to broader legal matters of guilt and in-court actions. Previous research on PRC criminal trials has focused mainly on questions and turn formulation by judges and procurators (Liao, 2003, 2012; Gao, 2003; Zhang and Jin, 2004; Meng, 2009); this study complements existing research by analyzing defendants’ speech in its interactional context.

How the shadow of the future might promote cooperation

It has been suggested that the expectation of repeated (versus single) interaction might promote cooperation in social dilemmas. One key question is whether the anticipation of repeated interaction may promote cooperation in those with prosocial orientations, with individualistic orientations, or both. We advance the argument that repeated interaction may be perceived in terms of opportunities for punishing noncooperation and rewarding cooperation (reciprocity), and that such “contingencies” should have a relatively greater impact on individualists’ motivations to cooperate. Consistent with hypotheses, we found evidence for the idea that the mere anticipation of repeated (versus single-trial) interaction promoted cooperation, but more so in those who pursue primarily individualistic, self-interested goals than those who are more prone to pursue prosocial goals.

Barley malting quality: are we selecting the best?

This paper presents an analysis of several key barley malting traits from 2 mapping populations grown as a series of multi-environment field trials. The analysis is based on a mixed model that includes terms for all sources of variation in the trait data, namely varieties, variety by trial interaction, variation between plots in the field, and variation between samples in the laboratory processes required to measure the traits. The base-line model is extended to accommodate variance heterogeneity and correlated effects for many of the terms in the model. The results show that accounting for these phenomena may cause substantial changes in variety rankings. The methods of design and analysis proposed in this paper for barley quality trait data do not have common usage so if adopted in future there is an opportunity for substantial improvements in response to selection.

Genotype × trial interaction and stability across sites in 11 combined provenance and clone experiments with Picea abies in Denmark and Sweden

In 1997, eleven combined Picea abies (L.) Karst. provenance and clone trials were assessed in two series, with identical genetic constitution and design, in locations ranging from western Denmark to central Sweden, after 14 and 11 years, respectively. The phenotypic variation was larger for mixtures of 24 clones than for seedlings in one series, although 10 times more genotypes were represented amongst the seedlings. This was explained by random C-effects due to propagation. Provenances of seedlings and clone mixtures were fairly stable across sites. Statistically significant clone × trial interaction of growth traits were of the same magnitude as the clonal effects. The median genotypic correlation across sites for total height growth was 0.54. Ecovalence values for growth indicated that most clones contributed about equally to the interaction, with a tendency for clones with early bud break to give a larger contribution. Damage caused by late spring frost was assumed to be a main cause of genotype × environment interaction. Since interactions relatively were more pronounced for growth increment than for the latest height, the interaction seems to increase with age. Cluster analysis based on genotypic correlations between pairs of trials gave a very scattered geographic pattern of the test sites. The results did not justify any suggestions for changes in the P. abies breeding strategy.

A Power Comparison of the Welch-James and Improved General Approximation Tests in the Split-Plot Design

Power for the improved general approximation (IGA) and Welch-James (WJ) tests of the within-subjects (trials) main effect and the within-subjects × between-subjects (groups × trial) interaction was estimated for a design with one between- and one within-subjects factor. The distribution of the data had two levels: multivariate normal and multivariate lognormal Power estimates for conditions in which there were between-groups differences in dispersion matrices showed that, for both effects, there were conditions in which the IGA test was more powerful and conditions in which the WJ test was more powerful. The power advantage for the IGA test tended to be fairly small, whereas the power advantage for the WJ test was quite large in many conditions. Furthermore, the number of conditions favoring the WJ test was much larger than the number of conditions favoring the IGA test. Power for IGA, WJ, ε̃-adjusted, and MANOVA tests was compared for conditions in which dispersion matrices were equal across groups. Results indicate that little if any power was sacrificed by using WJ or IGA tests in place of MANOVA or ε̃-adjusted tests.