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Two stages in research on scientific literary are identified: a composite saturation stage in which definitions covered all objects of science education and a stage where researchers focused on small manageable portions of scientific literary. Initial and continuous scientific literacy research in which the focus is on cognitive preference for science and informal science teaching is described. Underlying cognitive preference is a value preference for science. Three interdependent but clearly distinguishable forms of science teaching, formal, nonformal and informal, are described. Informal science teaching is identified as a condition for and an outcome of scientific literacy.  相似文献   
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The validity and reliability of curriculum‐based measures in reading as indicators of performance and progress for secondary‐school students were examined. Thirty‐five grade 8 students completed reading aloud and maze‐selection measures weekly for 10 weeks. Criterion measures were the state standards test in reading and the Woodcock–Johnson III Test of Achievement. Different time frames for each measure were compared. Most alternate‐form reliability coefficients were above .80. Criterion‐related validity coefficients ranged from .77 to .89. No differences related to time were found. Only maze selection reflected significant growth, with an average increase of 1.29 correct choices per week. Maze growth was related to the reading performance level and to change on the Woodcock–Johnson III from pre‐ to posttest.  相似文献   
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The technical study of wall paintings from the Buddhist temple complex at Nako, Western Himalayas, was one of the basic preconditions required for designing an appropriate conservation strategy. The complex, composed of four temples from the eleventh–twelfth century, offered a unique possibility to carry out a comprehensive research of technology and painting materials used in early and later western Tibetan Buddhist wall paintings as well as a comparative assessment with murals from other sites in the Western Himalayas. The study was based on extensive fieldwork and an integrated analytical approach comprising a wide range of non-destructive and micro-destructive methods. Answering the question of the coevality of paintings in the smaller temples with other original murals, the precise characterisation of binding media, the detection of the yellow dye gamboge and natural minerals posnjakite and brochantite identified for the first time in Himalayan murals, the clarification of technology of metal decoration, and the making of raised elements are some of the most exciting results which emerged from the research.  相似文献   
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Longitudinal changes in height, weight and physical performance were studied in 33 Flemish male youth soccer players from the Ghent Youth Soccer Project. The players' ages at the start of the study ranged from 10.4 to 13.7 years, with a mean age of 12.2 +/- 0.7 years. Longitudinal changes were studied over a 5 year period. Peak height velocity and peak weight velocity were determined using non-smoothed polynomials. The estimations of peak height velocity, peak weight velocity and age at peak height velocity were 9.7 +/- 1.5 cm x year-1, 8.4 +/- 3.0 kg x year-1 and 13.8 +/- 0.8 years, respectively. Peak weight velocity occurred, on average, at the same age as peak height velocity. Balance, speed of limb movement, trunk strength, upper-body muscular endurance, explosive strength, running speed and agility, cardiorespiratory endurance and anaerobic capacity showed peak development at peak height velocity. A plateau in the velocity curves was observed after peak height velocity for upper-body muscular endurance, explosive strength and running speed. Flexibility exhibited peak development during the tear after peak height velocity. Trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt and the training load should also be individualized at this time.  相似文献   
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The radial and axial motions of electrons in the betatron are described by means of a potential function of forces. Previously reported conditions of equilibrium, stability and damping of oscillations are derived for the region of parabolic variation of the potential. Extension of the analysis to, non-parabolic regions gives an account of the injection in conventional instruments in better agreement with experiment, particularly in regard to higher voltages of injection.Space charge limitations are discussed with the help of the Laplacian of the potential of forces.By means of an additional radial electric field electrons can be introduced as in the magnetron, without any asymmetry inherent in the conventional betatron circumferential injector. The analysis of the conditions of equilibrium and stability, greatly facilitated in this case by the notion of potential, shows that no substantial improvement in space charge limitations can be expected and that the required variations between the flux linking the electron orbits and the magnetic and electric fields at the orbits are difficult to realize on account of their complexity and narrow tolerances. The X-ray output of a small experimental double yoke instrument was measured by a phototube multiplier viewing an irradiated fluorescent screen and gave evidence of multiple group electron capture.  相似文献   
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