Overconfidence produces underachievement: Inaccurate self evaluations undermine students’ learning and retention

The function of accurately monitoring one’s own learning is to support effective control of study that enhances learning. Although this link between monitoring accuracy and learning is intuitively plausible and is assumed by general theories of self-regulated learning, it has not received a great deal of empirical scrutiny and no study to date has examined the link between monitoring accuracy and longer-term retention. Across two studies, college students paced their study of key-term definitions (e.g., “Proactive interference: Information already stored in memory interferes with the learning of new information”). After all definitions were studied, participants completed practice cued recall tests (e.g., “What is proactive interference?”) in which they attempted to type the correct definition for each term. After each test trial, participants judged how much of their response was correct. These study-test-judgment trials continued until a definition was judged as correct three times. A final cued recall test occurred two days later. In Study 1, judgment accuracy was manipulated experimentally, and in Study 2, individual differences in accuracy were examined. In both studies, greater accuracy was associated with higher levels of retention, and this link could not be explained by differential feedback, effort during study, or trials to criterion. Results indicate that many students could benefit from interventions aimed at improving their skill at judging their learning.     

Towards a renaissance in urban parks

Public parks have been a familiar and popular feature of our towns and cities since their appearance throughout the 19th century. They arose out of social concern over public health and happiness and as a reaction to the squalid conditions endured by the masses. Civic pride determined that they were maintained to a very high standard as symbols of municipal power and excellence. Public parks were the first resort for local communities, especially children, to have fun and to relieve the pressures of modern life. As well as providing an urban pastoral they also provided for the exuberance of amatuer sport and lively play. They continued and strengthened the British fascination with horticultural magnificence ‐council apprenticeships provided the head gardeners for the National Trust and private estates as well as the men who competed with their peers in ever more imaginative and technically accomplished picture‐and carpet‐bedding displays which adorned the nation's premier public parks.

All this has sadly passed. The decline of parks can be traced back to the removal of railings for the War effort and consequent loss of sense of place, but the real damage became cumulative from the mid‐1970s. Local government reorganisation, political struggle between local and central government, privatisation of local services, year‐on‐year cuts in capital and revenue budgets and a shift of emphasis to foreign holidays and car‐borne countryside recreation all contributed to the downfall of urban parks into the dismal, neglected and vandalised landscapes which have become so familiar today. Responding to the concerns of voluntary and professional bodies, the Heritage Lottery Fund launched the Urban Parks Programme in 1996 to begin to address the issues. The Urban Parks Programme experience has highlighted how seriously underfunded parks have been and has committed far more money than intended to tackle the massive backlog of repairs to essential park infrastructure. It has also tried to address the causes of decline in partnership with local authorities and other bodies in the field ‐ loss of management structure and skills, lack of political support and understanding, and dearth of relevant data concerning parks.

This article traces the fortunes of public parks from their inception to their decline and documents the stirring of a potential renaissance as the government shows its concern with quality of life issues, with social exclusion, with multiple deprivation and with regeneration of the economic vitality and social coherence of urban areas. A government Select Committee has recently examined the state of the nation's parks and declared itself shocked and appalled at the extent of the problems that parks have faced in the last 30 years. There is now a chance that the long downward trend in the status and condition of urban parks can be reversed if a vigorous lead is given by government.     

Estimation of thigh muscle and adipose tissue volume using magnetic resonance imaging and anthropometry

Thigh muscle volume is a useful determinant of functional fitness. However, anthropometric prediction of muscle content is influenced by the variability of adipose tissue accumulation. The aims of this study were to predict thigh muscle and adipose tissue volumes from anthropometry and to assess the validity of the method by examining the various components of the measurements and the assumptions involved. The 19 participants (9 men, 10 women; age 23-49 years) varied in adiposity. They all underwent magnetic resonance imaging (MRI) of the upper leg and the eight men and two women with the lowest adiposity underwent detailed anthropometry involving girths and skinfolds. Using MRI as the reference method, muscle volume was predictedfrom anthropometry using a circular concentric model, and the assumptions inherent in the method were tested further using the MRI data alone. Muscle volume was best predicted by anthropometry in the 10 leanest participants using a five-slice truncated cone model that overestimated the mean MRI value by 30% (R2 = 0.95; standard error of estimate = 288 cm3; P < 0.001). A single skinfold plus girth measurement at the mid-thigh almost matched its predictive ability, but with an increased bias. Measurements of leg circumference by means of the two techniques agreed well. The assumption of a circular cross-section was valid. In contrast, the agreement between skinfold thickness measured by caliper and superficial adipose tissue thickness by MRI was poor, contributing to the scatter of fat and lean area comparisons. An anterior skinfold thickness measurement underestimated the area of superficial adipose tissue at that level, particularly at the most proximal and distal sites. Although these limitations increase the uncertainties of muscle volume determination by anthropometry, they do not prevent its valid prediction in leaner individuals. The prediction of superficial adipose tissue was poorer.     

生死相拥5000年

[1](路透社)意大利瓦尔达罗电——意大利将不会分离它石器时代的“情侣”。[2]科学家说他们决定把这对相拥5000年之久的情侣遗体整体移动并保存,作为献给全国的情人节礼物,在他们永远拥抱的姿势中,他们的胳膊仍然相互缠绕在一起。     

Phosphate loading and the effects on VO2max in trained cyclists

It is known that an increased level of red blood cell 2,3-diphosphoglycerate (DPG) shifts the oxyhemoglobin dissociation curve to the right, thus allowing a greater unloading of oxygen at the tissue level. It has been hypothesized that phosphate might help increase VO2max by increasing 2,3-DPG level. Eight trained cyclists underwent three cycle ergometer tests (control, placebo, and experimental) to determine whether phosphate ingestion had any positive effect on VO2max, time to exhaustion, serum 2,3-DPG, and serum phosphate levels. We found no change between the control, placebo, or experimental conditions in pretest serum phosphate levels, but we did find increases in 2,3-DPG levels in the phosphate condition (p less than .05), which suggests that even a small amount of phosphate could increase levels of 2,3-DPG. We also found significant differences in VO2max between the control (p less than .05) and placebo (p less than .02) conditions and also in time to exhaustion between the three conditions (p less than .05). We suggest that phosphate may have an ergogenic effect, but clearly more work needs to be undertaken to ascertain the amount of phosphate required and the magnitude of the effect.