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51.
Heidemarie Laurent 《Parenting, science and practice》2019,19(1-2):94-96
SYNOPSISParental neuroimaging promises to shed light on how humans adapt to the demands of parenthood, but this research is not without challenges. A study in this issue reports differences between mothers’ and non-mothers’ default mode network activation during a goal-oriented task accompanied by human vocalizations. However, they did not find hypothesized differences in response specifically to infant cry, and the reach of conclusions that can be made based on these findings is limited. In my commentary, I present ideas for ways this work could be extended to make more definitive statements about the nature and potential benefits of parental brain adaptations. 相似文献
52.
Laurent Liégeois G′erard Chasseigne Sophie Papin Etienne Mullet 《International Journal of Science Education》2013,35(9):1129-1145
This paper reports two studies into the understanding of the concept of potential difference in the current-potential difference-resistance context among 8th-12th graders (Study 1), and the efficiency of a learning device derived from Social Judgment Theory (Study 2). These two studies showed that: (a) when asked to infer potential difference from resistance and current information, most participants only relied on current and ignored or greatly underestimated the importance of resistance information; (b) exposure to an electricity course did not much alter the way participants infer potential difference from resistance and current information; (c) a simple learning device considerably improved the way participants infer potential difference from resistance and current information; and (d) this observed improvement promised to be durable, at least in the short term. 相似文献
53.
Heidemarie K. Laurent Leslie D. Leve Jenae M. Neiderhiser Misaki N. Natsuaki Daniel S. Shaw Philip A. Fisher Kristine Marceau Gordon T. Harold David Reiss 《Child development》2013,84(2):528-542
Child hypothalamic pituitary adrenal (HPA) activity was investigated as a moderator of parental depressive symptom effects on child behavior in an adoption sample (n = 210 families). Adoptive parents' depressive symptoms and child internalizing and externalizing were assessed at 18, 27, and 54 months, and child morning and evening HPA activity measured through salivary cortisol at 54 months. Children's daily cortisol levels and day‐to‐day variability were tested as moderators of longitudinal associations between parent and child symptoms at within‐ and between‐family levels. Mothers' symptoms related directly to child internalizing, but child evening cortisol moderated effects of fathers' symptoms on internalizing, and of both parents' symptoms on externalizing. Different paths of within‐family risk dynamics versus between‐family risk synergy were found for internalizing versus externalizing outcomes. 相似文献
54.
C. Matthew Laurent Michael C. Meyers Clay A. Robinson Lorna R. Strong Charles Chase Beelee Goodwin 《Journal of sports sciences》2013,31(7):709-716
Abstract The aim of this study was to assess and compare the validity of the portable VmaxST telemetry metabolic measurement device with that of a standard measurement system (Vmax29). Thirty asymptomatic, moderately active males provided written, informed consent and completed two maximal graded treadmill exercise tests (Bruce) using the VmaxST and the Vmax29 metabolic measurement systems. Tests were performed in random order on separate days to obtain peak values for time to exhaustion, heart rate, systolic and diastolic blood pressure, oxygen consumption ([Vdot]O2), carbon dioxide production ([Vdot]CO2), ventilation ([Vdot] E), and respiratory exchange ratio (RER). Multivariate analysis of variance revealed no significant main effect (P = 0.88) between the two systems across any variable, suggesting similar measurement capabilities between the two systems. Linear regression analyses revealed moderate to high coefficients of determination for [Vdot]O2 (r 2 = 0.99), [Vdot]CO2 (r 2 = 0.99), [Vdot] E (r 2 = 0.99), and RER (r 2 = 0.89). Furthermore, Bland-Altman analyses demonstrated that the VmaxST yielded similar values to the Vmax29, suggesting good agreement between the two systems. Agreement was confirmed when the differences between the methods resulted in a small range as identified by the 95% limits of agreement. Findings from the current study confirm that the VmaxST is a valid device for measuring metabolic and physiological variables during exercise within a controlled laboratory setting. 相似文献
55.
Caroline Arnoux-Nicolas Laurent Sovet Lin Lhotellier Jean-Luc Bernaud 《International Journal for Educational and Vocational Guidance》2017,17(2):165-185
The purpose of this study was to validate a psychometric instrument among French workers for assessing the meaning of work. Following an empirical framework, a two-step procedure consisted of exploring and then validating the scale among distinctive samples. The consequent Meaning of Work Inventory is a 15-item scale based on a four-factor model, and assesses the importance, understanding, direction, and purpose of work. The results indicate that this instrument is reliable for assessing the meaning of work in the French context. Implications for career counseling practices are discussed. 相似文献
56.
Ivan Dalley Crozier Susan Hardy David Rutledge Niall Shanks Ian J. Slater Daryn Lehoux Alan Chalmers Shaughan Lavine Richard McDonough Paul Redding Katherine Neal David J. Stump Nicolas Rasmussen Fa-ti Fan David Oldroyd Iain Davidson Hanne Andersen Vassiliki Betty Smocovitis Ivan Crozier Anjan Chakravartty King’s College John Laurent Ian Tyrell Susan Spath Roy MacLeod 《Metascience》2001,10(3):412-506
57.
Gabriele Perozzi Denis Efimov Jean-Marc Biannic Laurent Planckaert 《Journal of The Franklin Institute》2018,355(12):4809-4838
The problem of position tracking of a mini drone subject to wind perturbations is investigated. The solution is based on a detailed unmanned aerial vehicle (UAV) model, with aerodynamic coefficients and external disturbance components, which is introduced in order to better represent the impact of the wind field. Then, upper bounds of wind-induced disturbances are characterized, which allow a sliding mode control (SMC) technique to be applied with guaranteed convergence properties. The peculiarity of the considered case is that the disturbance upper bounds depend on the control amplitude itself (i.e. the system is nonlinear in control), which leads to a new procedure for the control tuning presented in the paper. The last part of the paper is dedicated to the analysis and reduction of chattering effects, as well as investigation of rotor dynamics issues. Conventional SMC with constant gains, proposed first order SMC, and proposed quasi-continuous SMC are compared. Nonlinear UAV simulator, validated through in-door experiments, is used to demonstrate the effectiveness of the proposed controls. 相似文献
58.
This study aimed to investigate the acute effects of two barbell hip thrust-based post-activation potentiation (PAP) protocols on subsequent sprint performance. Using a crossover design, eighteen soccer athletes performed 5 m, 10 m, and 20 m sprints before and 15 s, 4 min, and 8 min after two PAP protocols. The PAP conditioning activities consisted of hip thrust exercises loaded with either 85% 1RM or a load for optimum power development. The resulting 5 m and 10 m sprint performances were impaired at 15 s following both protocols. At 4 min and 8 min, meaningful improvements were observed for the three sprint distances following both of the protocols. Meaningful differences were found when comparing the two PAPs over time: greater impairments in 5 m and 10 m following the 85% of 1 RM protocol after 15 s, and greater improvements in all sprint distances after 4 min and 8 min following the optimum power development protocol. Positive correlations between the hip thrust's 1RM and power values and the overall individual PAP responses were found. This investigation showed that both heavy-loaded and optimum-power hip thrust exercises can induce a PAP response, with the optimum-power development protocol preferred due its higher efficiency. 相似文献
59.
The Fukushima accident was a crisis in Japan, and a crisis elsewhere. In Europe, the aftermath of Fukushima was a period of intense questioning, about how to ensure the safety of nuclear reactors, and how, at the same time, ensure the ability of the European Union to act as a consistent political actor in the face of potentially catastrophic risks. Using empirical material related to the post-Fukushima stress tests and the subsequent discussions about the European regulatory framework for nuclear safety, this paper shows that stress tests have provided a peculiar form of European intervention, restabilizing regulatory boundaries while extending the European gaze. It describes the overall operation thereby performed as the “normalization of the crisis” whereby the exceptional situation enters the realm of the normal functioning of the public administrations, and where the actions undertaken take the form of the legal norm.
相似文献60.
Laurent Vigouroux Marine Devise Théo Cartier Clément Aubert Eric Berton 《Journal of sports sciences》2019,37(8):886-894
Pull-ups are often used by sport-climbers and other athletes to train their arm and back muscle capabilities. Sport-climbers use different types of holds to reinforce finger strength concomitantly. However, the effect of grip types on pull-up performance had not previously been investigated. A vertical force platform sensor measured the force exerted by climbers when performing pull-ups under six different grip conditions (gym-bar, large climbing hold, and four small climbing holds: 22mm, 18mm, 14mm, and 10mm). The electromyography of finger flexors and extensor muscles were recorded simultaneously. The maximal arm power and summed mechanical work were computed. The results revealed that the number of pull-ups, maximal power, and summed mechanical work decreased significantly with the size of the climbing hold used, even if no differences were found between a large climbing hold and a gym-bar. Electromyography of the forearm muscles revealed that the use of a climbing hold generated finger flexor fatigue and that the level of cocontraction was impacted by the different segment coordination strategies generated during the pull-ups. These findings are likely to be useful for quantifying training loads more accurately and designing training exercises and programs. 相似文献