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61.
Quantum information theory holds the promise of revolutionizing technologies other than computing and communications. In this article we show how quantum entanglement can be harnessed to beat the Rayleigh diffraction limit of conventional optical lithography, and to permit nano-devices to be fabricated at a scale arbitrarily shorter than the wavelength used. Given the relative ease of performing optical lithography compared with other schemes, and the relative costs associated in migrating the lithography industry to each new fabrication technology, exploiting quantum entanglement to extend the useful life of optical lithography could be economically attractive.  相似文献   
62.
A heterogeneous sample of 137 school-aged children with learning disabilities (IQ > 80) attending special needs schools was examined on the Movement Assessment Battery for Children (MABC). The results show that compared to the available norm scores, 52.6% of the children tested performed below the 15th percentile on manual dexterity, 40.9% on ball skills, and 33.7% on balance skills. Furthermore, after controlling for IQ, significant small to moderate partial correlations were found between spelling and mathematics and the MABC total score, as well as small to moderate correlations between mathematics and balance, between reading and ball skills, and between spelling and manual dexterity. The present findings are compared with previously reported results obtained in more homogenous groups, and based on the resultant relationships between academic performance and motor development, recommendations for future motor intervention studies are made.  相似文献   
63.
Purpose. We aimed to determine the effect of speed-induced changes in foot contact patterns on the vertical instantaneous loading rate (VILR). We hypothesized that transition runners, i.e. runners that shift towards a mid- (MF) or forefoot contact pattern (FF) when running speed increases, show smaller increases in VILR than non-transition runners, i.e. runners that remain with a rearfoot contact pattern (RF).

Methods. Fifty-two male and female runners ran overground at 3.2, 4.1, 5.1 and 6.2?m?s?1. Ground reaction forces, lower limb sagittal plane knee and ankle kinematics and plantar pressures were recorded. Multi-level linear regression models were used to assess differences between transition and non-transition runners.

Results. Non-transition runners experienced larger speed-induced increases in VILR (48.6?±?2.6?BW?s?1 per m?s?1) than transition runners (–1.4?±?7.6?BW?s?1 per m?s?1). Transition runners showed higher VILRs and a more flat foot touch down at the same pre-transition speed than non-transition runners.

Conclusion. When running speed increases, some runners transition towards more anterior foot contact patterns. This reduces or even eliminates the speed-induced increase in VILR. This result is especially the case for those RF runners who already have relatively high VILRs and flat foot positioning at slower running speeds.  相似文献   
64.
Wesseling  Ralph  Reitsma  Pieter 《Reading and writing》2000,13(3-4):313-336
This study explores early stages of reading acquisition, specifically therelation of phoneme blending and letter recoding to individual differencesin word decoding. The hypothesis was that facility in letter recoding andaccuracy of phoneme blending are substantial components of word decodingin beginning readers but not for skilled reading and that reliance onphoneme-sized decoding of words would dissipate as reading proficiencyincreased. In four studies we examined the ability to recode letters, blendphonemes and decode words in four groups of Dutch children (early Grade1, N = 130, older Grade 1, N = 81, Grade 3, N = 54 and a group of children witha reading lag, N = 356). Phoneme blending was only related to the readingability of beginning Grade 1 children. By the end of Grade 1 ability to blendphonemes did not differentiate reading capacity, nor for older children inGrade 3 and reading disabled children. Letter recoding was related to worddecoding in all four studies, although the strength of that relation diddwindle as reading skill level increased. The results of the study appearconsistent with self teaching hypothesis and other theories that imply atransient role of explicit phonological recoding in word identification.  相似文献   
65.
66.
Spelling pronunciations are hypothesized to be helpful in building up relatively stable phonologically underpinned orthographic representations, particularly for learning words with irregular phoneme-grapheme correspondences. In a four-week computer-based training, the efficacy of spelling pronunciations and previewing the spelling patterns on learning to spell loan words in Dutch, originating from French and English, was examined in skilled and less skilled spellers with varying ages. Reading skills were taken into account. Overall, compared to normal pronunciation, spelling pronunciation facilitated the learning of the correct spelling of irregular words, but it appeared to be no more effective than previewing. Differences between training conditions appeared to fade with older spellers. Less skilled young spellers seemed to profit more from visual examination of the word as compared to practice with spelling pronunciations. The findings appear to indicate that spelling pronunciation and allowing a preview can both be effective ways to learn correct spellings of orthographically unpredictable words, irrespective of age or spelling ability.  相似文献   
67.

Introduction

The determination of lipid biomarkers by capillary sampling may be useful in the screening, diagnosis and/or personal management of hyperlipidemia and cardiovascular risk. It remains unclear whether the use of the Accutrend® Plus system is appropriate. This study aimed to assess its reproducibility, accuracy and concordance for blood lipid profiling in adults.

Materials and methods:

Fasting capillary total cholesterol (TC) and triglyceride (TG) concentration on Accutrend® Plus were compared with their venous analogues obtained by a laboratory reference method in sixty-one adults (27 men and 34 women, aged 33.0 years). Supplementary capillary sampling was performed at two consecutive days taking into account macro-nutrient intake.

Results:

The day-to-day reproducibility of the Accutrend® Plus system proved to be high for TC (ICC = 0.85, P < 0.001), but moderate for TG (ICC = 0.68, P < 0.001). Strong correlations (r ≥ 0.80, P < 0.001) with the reference method were found for TC and TG. Mean difference (limits of agreement) were: 0.26 mmol/L (−0.95, 1.47) for TC, and −0.16 mmol/L (−1.29, 0.98) for TG. The concordance for subject classification according to the National Cholesterol Education Program (NCEP) guidelines was significant (P < 0.001), with substantial agreement for TC (κw = 0.67), and moderate agreement for TG (κw = 0.50).

Conclusions:

Day-to-day reproducibility of the Accutrend® Plus device for TC and TG is not optimal and lacks accuracy when compared to the reference laboratory method. The concordance between both methods for classifying subjects according to the NCEP is inadequate. Accutrend® Plus device should not be interchangeably used as a substitution for the standard laboratory methods in the diagnosis of hyperlipidemia.  相似文献   
68.
When radical innovations impact an industry, established incumbents are sometimes displaced by new challengers, yet at other times, survive and prosper. What are the factors that influence these possible outcomes? Extensive as the studies are in providing insights into incumbent-challenger dynamics (ICD), the fragmented nature of the literature and the isolated treatment of various constructs at a particular level of analysis, merit a review and analysis. We (1) identify, collate and analyse several constructs from three categories; the industry, the firm and the challenge, (2) discuss the interactions among these constructs and (3) show that incumbent failure or success can be better understood when these constructs are concurrently analysed. We derive several propositions for stimulating research and develop a holistic multi-level framework for understanding incumbent-challenger dynamics. We pull together strategic management theories at the industry level with those at the organizational and inter-organizational levels in the context of disruptive innovations. We contribute by bringing in the challenge dimension across these levels to inform whether an innovation is disruptive in its effects, not just ex post but also ex ante. For illustrative purposes and to concretize our arguments, we draw on both primary data from the Dutch television industry and archival data from four episodes of disruptive innovations.  相似文献   
69.
To date, the historical entanglement of disability and happiness has not been considered an object worth of historical inquiry. Nor has the intersection of disability and emotions been used as a lens to examine the history of disability. Our paper aims at filling this academic void by analysing a wide range of philosophical, anthropological, pedagogical, popular and poetic texts dealing with the following question: “Who is unhappiest, the blind or the deaf?” On the basis of a comparative study of Belgian, Dutch, German, Swiss, Austrian, British and American primary source material, we argue that the transformation of western concepts of happiness during the nineteenth century was reflected in attitudes towards people with sensory disabilities. If at the turn of the eighteenth century happiness was considered a sensory experience, it very soon became dependent on the intervention of an educational expert. On the basis of our source material we draw the conclusion that happiness has been an overlooked factor in the construction and problematisation of disability in western societies. Analysis of the ways in which nineteenth-century authors have dealt with this question also shows how happiness became connected to new ways of wielding power, and in particular to the rise of the educational expert.  相似文献   
70.
The acquisition of addition facts was investigated in a practice study. Participants were 103 Grade 1 children who practiced simple addition problems with three different methods: (a) writing down the answer, (b) choosing between two alternative answers, and (c) filling in the second missing addend. On a test with simple addition problems, children who practiced with the Choice method showed positive transfer: choosing between two answers was about as effective for learning addition facts as the conventional method of writing down the answer. There was no transfer effect for children who practiced with the Missing-Addend method. The results are in accordance with network theories on arithmetic fact learning and specifically the Identical Elements (IE) model of arithmetic fact representation.  相似文献   
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