Biomechanical and energetic determinants of technique selection in classical cross-country skiing

Classical cross-country skiing can be performed using three main techniques: diagonal stride (DS), double poling (DP), and double poling with kick (DK). Similar to other forms of human and animal gait, it is currently unclear whether technique selection occurs to minimize metabolic cost or to keep some mechanical factors below a given threshold. The aim of this study was to find the determinants of technique selection. Ten male athletes roller skied on a treadmill at different slopes (from 0° to 7° at 10 km/h) and speeds (from 6 to 18 km/h at 2°). The technique preferred by skiers was gathered for every proposed condition. Biomechanical parameters and metabolic cost were then measured for each condition and technique. Skiers preferred DP for skiing on the flat and they transitioned to DK and then to DS with increasing slope steepness, when increasing speed all skiers preferred DP. Data suggested that selections mainly occur to remain below a threshold of poling force. Second, critically low values of leg thrust time may limit the use of leg-based techniques at high speeds. A small role has been identified for the metabolic cost of locomotion, which determined the selection of DP for flat skiing.     

Dimensions of “uniquely” and “non‐uniquely” human emotions

Emotion scientists often distinguish those emotions that are encountered universally, even among animals ( “primary emotions”), from those experienced by human beings ( “secondary emotions”). No attempt, however, has ever been made to capture the lay conception about this distinction and to find the criteria on which the distinction is based. The first study presented in this paper was conducted in three countries involving four languages, so as to allow for cross‐cultural comparisons. Results showed a remarkable convergence. People from all samples not only differentiated between “uniquely human” and “non‐uniquely human” emotions on a continuum, but they did so on the same basis as the one used by emotion scientists to distinguish between “primary” and “secondary” emotions. Study 2 focused on the implicit use of such a distinction. When confronted with a human (animal) context, participants reacted faster to secondary (vs primary) emotions. The implications of the human uniqueness of some emotions within the social and interpersonal contexts are discussed.     

Gaze direction and facial expressions exert combined but different effects on attentional resources

Gaze direction and facial expressions are critical components of face processing and have been shown to influence attention deployment. We investigated whether gaze direction (direct vs. averted) combined with a neutral or angry expression modulates the deployment of attentional resources over time. In a Rapid Serial Visual Presentation (RSVP) paradigm participants had to decide the gender of a neutral or an angry target face with direct or averted gaze (T1) and then to judge the orientation of a target picture of a landscape (T2), following the face at different time intervals. Results showed no attentional blink effect (i.e., no deterioration in T2 accuracy) when T1 was an angry face with direct gaze, whereas it was present for angry faces with averted gaze or neutral faces with either averted or direct gaze. These findings are consistent with appraisal theories and are discussed against the background of automatic processing of threat stimuli.     

Amélioration de la qualité de vie au travail dans les unités de soins : la démarche ORSOSA

Improve the quality of working conditions is a major issue for healthcare workers who have to deal with productivity obligations and multiple procedures. Based on the magnet hospital concept, the ORSOSA study (prospective cohort study of 4000 helthcare workers) helped develop and validate a methodolody that allows to quickly diagnose the levels of psychological and organizational constraints (CPO) from the staff’s point of view / of the staff. The ORSOSA method relies on an organisational psychologist who launches a dynamic during the diagnostic feedback phase. He gets the team to appropriate the strengths and weaknesses and to rank their recommendations. This article presents an overview of the method and it the first stages of its evaluations.     

Brain Oxidative Damage Following Acute Immobilization and Mild Emotional Stress

We studied the role of free radicals on brain oxidative damage in rats after acute immobilization stress (restraint) and mild emotional stress (handling). To investigate brain oxidative damage, CuZn and Mn dependent superoxide dismutase (CuZn SOD, Mn SOD) activities, lipid peroxidation (TBARs), Na ⁺ K ⁺ ATPase activity, protein carbonyl (PrC), and reduced and oxidized glutathione (GSH, GSSG) levels were measured in the cerebral cortex (CTX), hippocampus (HIP), and striatum (ST) of the animals after the two different stress stimuli. Because stress produces abnormalities in the hypothalamic-pituitary-adrenal axis, the intensity of the two stress conditions were measured by plasmatic corticosteroid (COR) levels: particularly, COR levels doubled in handled rats and increased 15-fold in restrained animals. The SOD activities increased in CTX and decreased in HIP of the handled rats, while in ST a significant decrease in handled animals but an increase in restrained animals occurred. TBARs, GSH, and GSSG levels remained unchanged, while an index of glutathione redox decreased significantly in ST of handled animals and in CTX of restrained ones. Na ⁺ K ⁺ ATPase activity increased significantly in the HIP and ST of both groups of stressed rats. The stress induced a remarkable increase in PrC levels in all studied cerebral areas. These findings provide evidence to support the idea that stress produces oxidants but that the oxidative damage in stress differs in cerebral areas and could contribute to the degenerative mechanism of aging.     

Linguistic and prosodic aspects of child-directed speech: The role of maternal child-rearing experiences

This study explored if the quality of mothers’ reported child-rearing experiences influences the prosodic and linguistic features of maternal child-directed speech. Lexical, syntactic, functional and prosodic aspects of maternal speech directed towards their 24-month-old children were examined. Results showed that mothers with different child-rearing histories differed in the ways they talked to their children. Mothers who recalled the caregiving they received during childhood as characterized by high levels of care and low levels of control, used a lexically and syntactically more complex speech and expressed more positive emotions. This kind of input seems to be more attuned with the typical growing skills of two-year-old children. Implications for the study of mother–infant relationship as well as for the study of child language development are addressed.     

Motion aftereffects with rotating ellipses

Summary The perceptual outcome and the motion-aftereffect duration generated by the rotation on the frontal plane of an ellipse with a bar depend on whether the bar is placed along the major or the minor axis. When the bar is placed along the minor axis, a stereokinetic transformation occurs, and the pattern looks like a tilting ring with a perpendicular bar moving rigidly with it. Placing the bar along the major axis prevents the stereokinetic transformation: subjects report deformations and relative motion of the bar with respect to the ellipse. We found that motion aftereffects last longer when the bar is placed along the minor rather than along the major axis. A series of experiments was carried out to investigate whether differences in aftereffect duration are related to the stereokinetic transformation. Results seem to suggest that they are not.The authors' names are in alphabetical order.     

Maternal representation and care of infant sleep

Maternal reports about infant sleep care and ideas about the causes of awakening were obtained from telephone interviews with 104 middle class primiparae when their infants were 1 month and 1 year old. These reports were compared with their expectations about infant sleep before the birth of their child. It was found that most of the mothers were willing to ‘help’ their infants fall asleep, with 19 different kinds of techniques being spontaneously mentioned. Most of the techniques involved physical contact. The changes in technique from before birth to the end of the first year of life mainly concerned a decrease in the use of techniques involving holding the infant in the arms. From 1 month to 1 year, there was a decrease in rocking techniques, while at 1 year the use of a (bottle) feeding technique and taking the child into the parents' bed became apparent. The reasons mothers gave for infant awakenings varied from 1 month to 1 year. At 1 year, the most frequent reason was that the infant has ‘sufficient sleep’. Mothers' representations before the infant birth did not overlap with representations and reports of sleep handling after birth. Mothers were willing to apply and use a great variety of caring techniques that they perceived to be adjusted to the individual needs of their child. © 1998 John Wiley & Sons, Ltd.     

Children with low motor ability have lower visual-motor integration ability but unaffected perceptual skills

The purpose of this study was to examine perceptual, visual-motor abilities and intellectual skills in children with low, average and above average motor abilities. The participants were 144 children (aged 6-10 years) attending elementary school. Three groups of children were identified on the basis of their performance at the TGMD (Test of Gross Motor Development; [Ulrich, D.A. (1985). TGMD, Test of Gross Motor Development. Austin, Texas: PRO-ED. Edizione Italiana a cura di D. Ianes, TEST TGM. Test di valutazione delle abilita grosso-motorie. 1994, Trento: Edizioni Centro Studi Erickson]). Each child received an intelligence test (K-BIT; [Kaufman, A.S., & Kaufman, N.L. (1990). K-BIT. Kaufman Brief Intelligence Test. Circle Pines, MN: American Guidance Service]) and was evaluated for perceptual and visual-motor integration abilities (DTVP; [Hammill, D.D., Pearson, N.A., & Voress, J.K. (1993). Developmental Test of Visual Perception (2nd ed.). Austin, Texas: PRO-ED. Edizione Italiana a cura di D. Ianes, TEST TPV. Test di percezione visiva e integrazione visuo-motoria. Trento: Edizioni Centro Studi Erickson]). Results highlight a significant difference in visual-motor integration between children with high and low gross-motor abilities, in the absence of significant differences in perceptual skills or intellectual ability. The findings are discussed with reference to the concept of atypical brain development [Gilger, J.W., & Kaplan, B.J. (2001). Atypical brain development: A conceptual framework for understanding developmental learning disabilities. Developmental Neuropsychology, 20, 465].