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41.
We aimed (1) to test the acute impact of two high-intensity interval-training (HIIT) protocols differing in the level of effort on intraocular pressure (IOP) responses, and (2) to elucidate whether the IOP responses differ between men and women. Twenty-four physically active collegiate (12 men and 12 women) performed three protocols: low-fatigue HIIT (eight 30-m sprints with 60-s of rest), high-fatigue HIIT (eight 30-m sprints with 30-s of rest), and control (walking). IOP was taken at baseline, after sprints and recovery by rebound tonometry. Our data revealed an acute IOP reduction during both HIIT protocols compared to the control condition (effect size [ES]:0.81–1.65). The differences between both HIIT protocols were generally negligible (ES<0.30), however, the reduction of IOP was moderately higher for the low-fatigue HIIT protocol after the 7th (ES: 0.67) and 8th (ES: 0.74) sprints. Women showed a more prominent lowering effect on IOP during the control condition (ES: 0.42–1.02), and during the two first sprints of both HIIT protocols (ES: 0.54–1.03). These findings highlight that a time-efficient HIIT protocol may acutely reduce IOP levels, while low-fatigue HIIT protocol could be recommended since it induced a higher reduction on IOP than the high-fatigue HIIT protocol.  相似文献   
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Synchronised swimming involves a variety of sculling movements essential for body support and propulsion but its study is scarce. We aimed to biomechanically compare standard and contra-standard sculling techniques, and to observe the relationship between measures. Six synchronised swimmers performed two, 30 s maximal intensity, fully tethered standard and contra-standard sculling motions. Kinetic and kinematic data were obtained using a load-cell and underwater cameras, respectively. Force decreased along both techniques’ bouts, but no differences in-between techniques were noted for any kinetic variables. Standard sculling presented a higher cycle rate and a lower elbow mean angle than the contra-standard sculling (2.4 ± 0.3 vs. 2.0 ± 0.2 cycles/s and 134.1 ± 5.8 and 141.5 ± 4.7°, p < 0.05). In the standard sculling, by removing and maintaining the variation between participants (r w and r, respectively), the absolute mean force was directly related with cycle rate (r w  = 0.60) and wrist angular velocity during flexion (r = 0.82), while in the contra-standard condition the force was inversely associated with wrist mean angle (r = ?0.95) and directly with hand speed (r w  = 0.76), and elbow angular velocity (r w  ≈ 0.60). Therefore, technique learning and training require different attention by coaches and swimmers.  相似文献   
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ABSTRACT

A decontamination treatment using liquid CO2 (li-CO2) and specifically developed for the requirements of museum objects (Lombardo, T., M. Wörle, V. Hubert, E. Hildbrand, I. Mayer, C. Hinterleitner, U. von Arx. 2020. “Influence of Process Parameters on Chlorinated Biocide Decontamination by li-CO2 on Artificially Contaminated Model Materials.” Studies in Conservation, in press, doi:10.1080/00393630.2019.1641001) was first tested on model materials of wood (with and without coating), silk, and wool with different dyes, paper, and leather in order to evaluate possible material changes. Then, selected museum objects from the collection of the Swiss National Museum were treated to determine the efficiency of biocide decontamination and any resulting chemical and/or structural changes. Results show that dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and chlorpyrifos were successfully removed. Wool, silk, leather, and non-coated wood did not experience any detectable modifications, while moderate to major modifications were observed in wood coated with shellac and polychromy.  相似文献   
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Kay Chadwick 《Media History》2015,21(4):426-442
This article focuses on representations of Britain to occupied France by the BBC French Service via its flagship programme Les Français parlent aux Français [The French speak to the French]. It first examines the establishment of the service and the formulation of a British propaganda strategy on occupied France. It then explores the service's efforts to foster French belief in Britain as France's friend and ally, and to rationalise key issues and incidents which challenged that narrative. Simultaneously, it positions French Service endeavours alongside the propaganda delivered on French national radio, known as Radio Vichy, in order to explore the exchanges about Britain between French propagandists who spoke on behalf of different Frances. In so doing, the article provides a close reading of the original French Service broadcasts which covers a larger corpus of material than has hitherto been documented in published collections, and which extends existing knowledge on the topic.  相似文献   
48.
Grade retention and inequalities that derive from grade retention can influence student school trajectories and careers. Grade retention can discourage students from education, and increase school failure and dropout. This study explored the relationship between grade retention and student intentions to enrol in higher education. We also studied the role of school identification and behavioural engagement in this relationship. The analysis is based on a sample of 1,089 students (grades 6 to 10) from Portugal, one of the European countries with the highest rates of grade retention. We employed multilevel probit regression modelling with random intercept and fixed slopes to explore both the individual and school level effects of grade retention. The analyses showed that retained students had a lower probability of intent to enrol in higher education and that there was a contextual effect of the number of retained students in the school, on students' probability of intent to enrol in higher education. This association was partially explained at the individual level by students' school identification. Retained students presented lower levels of school identification, which in turn results in lower probabilities of enrolling in higher education. Student behavioural engagement was not associated with grade retention nor student intentions. Our findings suggest the need for interventions that foster students' school identification to overcome the adverse effects of grade retention.  相似文献   
49.

Introduction

Postmenopausal women have higher risk of cardiovascular disease. One of the contributing factors could be reduced activity of anti-atherogenic enzyme paraoxonase 1 (PON1). The aim of this study was to examine differences in the lipid status, paraoxonase and arylesterase PON1 activities and PON1 phenotype in women with regular menstrual cycle and in postmenopausal women.

Materials and methods:

The study included 51 women in reproductive age (25 in follicular and 26 in luteal phase of the menstrual cycle) and 23 women in postmenopause. Lipid parameters in sera were determined using original reagents and according to manufacturer protocol. PON1 activity in serum was assessed by spectrophotometric method with substrates: paraoxon and phenylacetate. PON1 phenotype was determined by double substrate method.

Results:

Compared to the women in follicular and luteal phase, postmenopausal women have significantly higher concentration of triglyceride [0.9 (0.7–1.3), 0.7 (0.6–1.0) vs. 1.5 (0.9–1.7) mmol/L; P = 0.002], cholesterol [5.10 (4.78–6.10), 5.05 (4.70–5.40) vs. 6.30 (5.73–7.23) mmol/L; P < 0.001], LDL [3.00 (2.56–3.63), 3.00 (2.70–3.70) vs. 3.90 (3.23–4.50) mmol/L; P < 0.001], and apolipoprotein B [0.88 (0.75–1.00), 0.79 (0.68–1.00) vs. 1.07 (0.90–1.24) mmol/L; P = 0.002]. PON1 basal [104 (66–260), 106 (63–250) vs. 93 (71–165) U/L; P = 0.847] and salt-stimulated paraoxonase activity [210 (131–462), 211 (120–442) vs. 180 (139–296) U/L; P = 0.857] as well as arylesterase activity [74 (63–82), 70 (54–91) vs. 70 (60–81) kU/L; P = 0.906] and PON1 phenotype (P = 0.810) were not different in the study groups.

Conclusion:

There are no differences in PON1 activity and PON1 phenotype between women with regular menstrual cycle and postmenopausal women.  相似文献   
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