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81.
82.
利用双标图分析基因型和环境交互作用   总被引:28,自引:0,他引:28  
在作物的品种区域化试验中,品种的基因型和环境(G×E)交互作用越来越受到重视.一种新的非常有效的分析G×E交互作用模型是加性主效应和乘积交互作用模型(简称AMMI模型),而双标图(biplot)是解释AMMI分析结果的一种直观有效的图形工具.本文对AMMI模型及双标图作一扼要介绍,并选用1995年南方水稻区试单季晚粳组数据作为实例,给出了两种新的双标图,以帮助我们更深入地了解G×E交互作用.  相似文献   
83.
This study explored the correspondence and differences between school staff perceptions of preschool children's social skills and behavior problems. One hundred preschoolers were assessed by 14 pairs of teachers and classroom aides with the Preschool and Kindergarten Behavior Scales – 2nd Edition (PKBS‐2 Portuguese version). Indexes of agreement and disagreement were calculated. Risk levels and item analyses of PKBS‐2 scores according to both informants' ratings were compared. A higher level of agreement was obtained for social skills scores than for behavior problems (mean correlation of .62). No statistically significant differences between informants were obtained for the risk levels, and item analyses revealed a similar pattern of behaviors that were most and least rated by both informants. Results indicate that the classroom aides' perspective on preschool assessment represents a reliable input, which justifies that they network with teachers in addressing preschoolers' social‐emotional and behavioral challenges.  相似文献   
84.
The overall intent of this study is to examine the relationship among several factors that influence the malnutrition of a select group of Filipino elderly in institutionalized setting. A total of 102 residents were purposively recruited from three different institutionalized care settings at the national capital region of the Philippines. A multi-aspect questionnaire was used to characterize the demographic and nutrition profiles of the participants. Data were treated statistically using the partial least square design. Notably, the study showed that 48.0% of the elderly residents in institutions were at risk of malnutrition, 36.3% were malnourished, and 15.7% have normal nutritional status. Malnutrition was found to be prevalent among the female group, aged >70 years old, functional impairment (= <0.01), poor eating habits (= 0.01), lower dietary intake (= 0.01), and eating difficulties (= 0.04). However, statistically significant relationships between eating habits (= 0.08) and dietary intake and comorbidities (= 0.32) and malnutrition were not established. Impliedly, administrators of homecare institutions are invited to pay greater attention to the nutritional status of the elderly by institutionalizing nutrition assessment and evaluation practices and nutrition care planning that respond to the identified nutritional needs and concern of the elderly.  相似文献   
85.
Reading relies on a left‐lateralized network of brain areas that include the pre‐lexical processing regions of the ventral stream. Specifically, a region in the left lateral occipitotemporal sulcus (OTS) is consistently more activated for visual presentations of words than for other categories of stimuli. This region undergoes dramatic changes at the functional and structural levels when children learn to read, but little is known about the effects of early cerebral constraints on reading skills. Using anatomical magnetic resonance imaging, we investigated whether the sulcal pattern of the lateral OTS—a stable brain feature—was associated with oral reading skills. The sulcal pattern of the left but not the right lateral OTS was associated with the number of words correctly read in 3 min. This study is the first to evidence that reading is affected by early cerebral constraints, such as the sulcal morphology of the left lateral OTS.  相似文献   
86.
Sequence learning in pigeons was studied in asimultaneous chaining paradigm: all stimuli and the opportunity to respond to each stimulus were available simultaneously. In contrast to the traditionalsuccessive chaining paradigm, a simultaneous chaining paradigm provides no differential feedback following each response (except the last). Subjects were first trained to perform on sequences of two (AB), then three (ABC), and then four colors (ABCD). Performance greatly exceeded that predicted by models of random choice. Generalization to novel arrays of three and four colors was complete. After training with a four-color sequence, the subjects were tested with subsequences consisting of all possible combinations of two and three of the four training colors (e.g., BD, AD, BC, ACD, BCD, etc.). The successful completion of these subsequences showed that the organization of the original sequence did not entail overt pecks to successive elements of that sequence. That subjects can respond accurately on nonadjacent subsets is not readily explained by a chaining theory, or by any theory that assumes that responding to element n provides a cue for responding to element n+1.  相似文献   
87.
This article examines Austria’s efforts to reform teacher education during the period of the Dual Monarchy, 1867–1914. It offers insight into the role of teachers in Austrian society and how this role changed over time. It demonstrates that, during this period, teaching became an institutionalised and professionalised occupation. This process of professionalisation brought teachers firmly under state control, leading to conflict between teachers and the Austrian educational bureaucracy. This process also led to the development of a robust network of teachers’ associations to represent the interest of Austrian teachers and to contribute to their professional development. This article utilises documents from the Austrian educational bureaucracy, printed curriculum and pedagogical journals to illustrate that Austrian teacher training reforms offer crucial insight into the development of public education in the late nineteenth century.  相似文献   
88.
Research in Higher Education - State financial aid grant programs are commonly categorized as either need-based, merit-based, or both, but their initial eligibility requirements include many more...  相似文献   
89.
90.
The purpose of this paper is to compute the Hankel transform Fn(y) of order n of a function f(x) and its inverse transform using rationalized Haar wavelets. The integrand is replaced by its wavelet decomposition. Thus representing Fn(y) as a Fourier-Bessel series with coefficients depending strongly on the local behavior of the function , thereby getting an efficient algorithm for their numerical evaluation. Numerical evaluations of test functions with known analytical Hankel transforms illustrate the proposed algorithm.  相似文献   
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