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141.
Philip B. Gough 《Reading and writing》1993,5(2):181-192
It is widely agreed that children recognize their first words in a different way than they later decode. One hypothesis is that sight words are recognized as wholes, another that they are recognized by parts. Two experiments were devised to compare these hypotheses. In one, children were taught a sight word accompanied by a salient extraneous cue and then tested for recognition of the word and the cue. In the other, children were taught sight words, then tested for recognition of each half of the word. The children were found to recognize the cue but not the word; they recognized one half of the word but not the other. The results support the idea that first words are recognized by selective association. 相似文献
142.
Parental reactions to children's negative emotions: longitudinal relations to quality of children's social functioning 总被引:7,自引:0,他引:7
Relations between self-reported parental reactions to children's negative emotions (PNRs) and children's socially appropriate/problem behavior and negative emotionality were examined longitudinally. Evidence was consistent with the conclusion that relations between children's externalizing (but not internalizing) emotion and parental punitive reactions to children's negative emotions are bidirectional. Reports of PNRs generally were correlated with low quality of social functioning. In structural models, mother-reported problem behavior at ages 10-12 was at least marginally predicted from mother-reported problem behavior, children's regulation, and parental punitive or distress reactions. Moreover, parental distress and punitive reactions at ages 6-8 predicted reports of children's regulation at ages 8-10, and regulation predicted parental punitive reactions at ages 10-12. Father reports of problem behavior at ages 10-12 were predicted by earlier problem behavior and parental distress or punitive reactions; some of the relations between regulation and parental reactions were similar to those in the models for mother-reported problem behavior. Parental perceptions of their reactions were substantially correlated over 6 years. Some nonsupportive reactions declined in the early to mid-school years, but all increased into late childhood/early adolescence. 相似文献
143.
144.
Lightman B 《Isis; an international review devoted to the history of science and its cultural influences》2000,91(4):651-680
This essay examines the use of visual images during the latter half of the nineteenth century in the work of three important popularizers of science. J. G. Wood, Richard Proctor, and Agnes Clerke skillfully used illustrations and photographs to establish their credibility as trustworthy guides to scientific, moral, and religious truths. All three worked within the natural theology tradition, despite the powerful critique of William Paley's argument from design set forth in Charles Darwin's Origin of Species (1859). Wood, Proctor, and Clerke recognized that in order to reach a popular audience with their message of divine wonder in nature, they would have to take advantage of the developing mass visual culture embodied in the new pictorial magazines, spectacles, and entertaining toys based on scientific gadgets emblematic of the reorganization of vision. But in drawing on different facets of the emerging visual culture and in looking to the images produced by the new visual technologies to find the hand of God in nature, these popularizers subtly transformed the natural theology tradition. 相似文献
145.
146.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the
present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma
Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating
patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and
10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase
(P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy
males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death. 相似文献
147.
C.S. Badue R. Baeza-Yates B. Ribeiro-Neto A. Ziviani N. Ziviani 《Information processing & management》2007
The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community. 相似文献
148.
Two property regimes for software development may be distinguished. Within corporations, on the one hand, a Private Regime obtains which excludes all outsiders from access to a firm's software assets. It is shown how the protective instruments of secrecy and both copyright and patent have been strengthened considerably during the last two decades. On the other, a Public Regime among hackers may be distinguished, initiated by individuals, organizations or firms, in which source code is freely exchanged. It is argued that copyright is put to novel use here: claiming their rights, authors write ‘open source licenses’ that allow public usage of the code, while at the same time regulating the inclusion of users. A ‘regulated commons’ is created. The analysis focuses successively on the most important open source licenses to emerge, the problem of possible incompatibility between them (especially as far as the dominant General Public License is concerned), and the fragmentation into several user communities that may result. 相似文献
149.
Thomas B. Åstebro 《Research Policy》2005,34(9):1404-1418
Research on technological opportunity has typically focused on the impact of broad industry characteristics on R&D intensity of firms. This study complements such approaches by examining the impact of a multidimensional vector that measures technological opportunity on independent inventors’ decisions to patent and commercialize inventions. Using data from 559 inventions and controlling for demand, appropriability, and competitive conditions, we found two of four tested dimensions of technological opportunity - technical performance and technical uncertainty - to be significant and important determinants of the likelihood of commercialization. Technical feasibility appears important in affecting patenting but unimportant in affecting commercialization. Technical significance carries a negative, although insignificant, sign conditioning commercialization. 相似文献
150.
官员退休通称致仕等,是中国古代封建王朝的重要议题。经过各个时期的不断调整,宋朝致仕制度也逐渐臻于完善。有宋一代,虽则出现了以王彦超为代表的一批知止而退的致仕官员,但年及而愿退者依然较少,官员恋栈现象仍然时有发生。导致官员恋栈的原因是多方面的,就主观层面而言,部分及年应退官员,或基于生计考虑,或缘于贪恋权财,而故作不知退。就客观层面而言,宋朝致仕标准"朝令夕改",具有极强的随意性特点,既褒奖提前退休,又额外奖励按时致仕,亦或惩处或者认可到时不退者,使得官员面对如此繁杂的情况,属实不知该退还是不该退,有些无所适从。最终他们在善变的致仕制度中徘徊前进,不知所措。 相似文献