Incremental training intensities increases loads on the lower back of elite female rowers

Lumbar-pelvic kinematics change in response to increasing rowing stroke rates, but little is known about the effect of incremental stroke rates on changes in joint kinetics and their implications for injury. The purpose of this study was to quantify the effects of incremental rowing intensities on lower limb and lumbar-pelvic kinetics. Twelve female rowers performed an incremental test on a rowing ergometer. Kinematic data of rowers’ ankle, knee, hip and lumbar-pelvic joints, as well as external forces at the handle, seat and foot-stretchers of the rowing machine were recorded. Inter-segmental moments and forces were calculated using inverse dynamics and were compared across stroke rates using repeated measures ANOVA. Rowers exhibited increases in peak ankle and L5/S1 extensor moments, reductions in peak knee moments and no change in peak hip moments, with respect to stroke rate. Large shear and compressive forces were seen at L5/S1 and increased with stroke rate (P < 0.05). This coincided with increased levels of lumbar-pelvic flexion. High levels of lumbar-pelvic loading at higher stroke rates have implications with respect to injury and indicated that technique was declining, leading to increased lumbar-pelvic flexion. Such changes are not advantageous to performance and can potentially increase the risk of developing injuries.     

标记系统及学术文本处理的未来（一）

标记事务影响着学者们对思考与写作系统的采纳使用。程序性标记和表示性标记会阻碍这一进程的发展,描述性标记则通过简化机械性任务,让学者们将注意力集中于内容上的做法,以加快这一进程。     

How do university teachers combine different approaches to teaching in a specific course? A qualitative multi-case study

Teaching approaches in higher education are at the general level well researched and have identified not only the two broad categories of content-focused and learning-focused approaches to teaching but also consonance and dissonance between the aspects of teaching. Consonance means that theoretically coherent teaching practices are employed, but dissonance occurs when two broad approaches are combined. Previous studies researched teaching approaches at the general level, whereas the present study, researched approaches to teaching at the course level. Three university teachers were interviewed in depth about their teaching approach to one particular course. Data were analyzed using qualitative content analysis. While previous studies have found that dissonance occurs between different aspects of teaching, this multi-case study revealed that dissonance can also be found within a single aspect. The present study suggests that neither content- nor learning-focused approaches to teaching are mutually exclusive and therefore may co-exist in individual teachers’ practices.     

Maltreatment of children in The Netherlands: an update after ten years

Governmental consultation and advice on child abuse and neglect in the Netherlands started in 1972 as a two-year experiment with four offices for "confidential doctors" in four major cities of the country. After these two experimental years, a governmental institute for prevention of child abuse and neglect was organized. Over the ensuing decade the number of offices increased to ten, covering the whole country. The State Department of Welfare, Public Health, and Environment collected data from the confidential doctors and their coworkers every year. This study compares the data of the first year 1974 with those of 1983 in order to detect changing patterns over a 10-year period. The major changes are as follows: a threefold increase in cases, an extraordinary increase in cases of emotional maltreatment, an increase in detection of child fatalities but decrease in severity of physical abuse. Sexual abuse was hardly recognized in 1974 but gradually was recognized more frequently during the study decade and accounted for an alarming 7.2% of detected cases of maltreatment in 1983. No change was found in the social conditions of the family and the identity of the perpetrators--primarily fathers and/or mothers. A decrease was noted in the percentage of married parents. The increased percentage of single parents was primarily represented by mothers alone. An increase in the numbers of victims residing at home and a decrease in the need for children's homes as a temporary or permanent residence is attributed to aftercare. The discrepancy between the results of this voluntary notification system in the Netherlands and the results of a mandatory reporting system as used in the U.S.A. is still very high. The hope is that the government will decide to make reporting of maltreatment mandatory for everyone.     

Sex Differences in Spatial Competence: the ability of young children to map ‘primed’ unfamiliar environments

Abstract This paper reports on a study set up to investigate the effects of gender related differences in home range behaviour on the acquision of spatial and environmental skills amongst a group of children aged 8 to 11. The population was divided to form two groups (A and B) of similar sex composition and environmental experience. The children were informed that the aim of the project was to construct a map of an unfamiliar area which they were to visit. The two groups were ‘primed’ about their task in different ways, with children in Group B undertaking a slightly more complex exercise. The results show that whilst ‘priming’ has the effect of reducing disjunction between the spatial capabilities of boys and girls on simpler tasks, when the exercise is complicated boys do much better than girls in all but one of the spatial assessments. Such evidence lends further support to those who argue that the more extensive movements of boys through the environment leads to superior spatial ability. The educational implications of the results are considered.     

Rats remember not wisely but too well

Rats were trained in a three-alternative spatial delayed matching-to-sample task in a starburst maze. Samples consisted of rewarded forced choices of one arm, and retention was indicated by rats’ returning to that arm after a 90-sec delay. If a rat made an error on its first choice, it was returned to the start compartment and allowed a second choice. Unlike in previous experiments with this task, all three arms were available during the animals’ second choices. The rats tended to perseverate in their second choices by returning to the arm that they had erroneously visited on their first choice. In Experiment 1, the accuracy of second choices following first-choice errors was below chance during the first block of sessions, when a 90-sec delay intervened between the first choice and the second choice, and at chance during the second block of sessions, when a short (5–6 see) delay intervened between first and second choices. In Experiment 2, long-delay and short-delay sessions were randomly presented to naive subjects. Similar results were obtained. In both experiments, the tendency to repeat the erroneous first choice was greater when long delays separated the two choices than when short delays were used. The results suggest that rats make their first-choice errors because they erroneously encode or remember the location of the sample and that they base their second choices on the same erroneous-memory. The increase in perseveration at long delays implies some kind of rehearsal-like mechanism that slows forgetting of the memory controlling the first choice.     

The role of educators of the deaf in the early identification of hearing loss

About 16,000 babies each year will be identified with hearing loss by age 3 months once universal newborn hearing screening becomes a reality. Identification of hearing loss in infancy, followed by appropriate intervention by age 6 months, can result in normal language development, regardless of degree of hearing loss. As the average age of identification of hearing loss moves downward toward 2 months, children with hearing loss will enter the educational system earlier and with language skills commensurate with those of their hearing peers. In order to provide appropriate services to children with hearing loss and their families, early interventionists will need to forge links to health care providers involved in universal newborn hearing screening programs, to have specialized training in deafness and hearing loss, and to have expertise in providing services to very young children and to children with hearing loss in the broad range from mild to profound.