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To extend the feedback analysis of legibility in handwriting, a coordinate force transducer has been devised that makes possible the separate sensing of the right-left and near-far directions of writing motions and the converting of these movements to their electrical analogs. This method of transducing handwriting motions made possible systematic measurement of the effects of feedback displacement and delay of the visual feedback of writing movements and of analyzing the types of variation in legibility related to variable feedback factors. Results showed that differential directional defects and general disturbances in legibility and timing of writing movements occurred in relation to both visual feedback displacement and delay of writing motions. The findings give added support to the view that writing is not a form of discrete stimulus-response behavior or stimulus tracking, but consists of self-generated forms of response comparable to steering, in which accuracy, legibility, and learning are directly determined by feedback time factors and directional specificity of particular right-left and near-far coordinates of movement that dynamically control and project visual input in the writing act.  相似文献   
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This article uses definitions provided by Cronbach in his seminal paper for coefficient α to show the concepts of reliability, dimensionality, and internal consistency are distinct but interrelated. The article begins with a critique of the definition of reliability and then explores mathematical properties of Cronbach's α. Internal consistency and dimensionality are then discussed as defined by Cronbach. Next, functional relationships are given that relate reliability, internal consistency, and dimensionality. The article ends with a demonstration of the utility of these concepts as defined. It is recommended that reliability, internal consistency, and dimensionality each be quantified with separate indices, but that their interrelatedness be recognized. High levels of unidimensionality and internal consistency are not necessary for reliability as measured by α nor, more importantly, for interpretability of test scores.  相似文献   
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Abstract

Citation management programs are tools used to organize references and to create citations and bibliographies. Libraries are often the central point for providing training and support in using these tools. To determine how we could improve our support and training services, we surveyed users to determine what software in being used, why they chose that particular program, what features are important, and how they use citation management programs to collaborate. Results indicate that users chose a particular program because it was freely available or recommended to them by others and that they thought that importing references and creating citations were important features. We also found a majority of respondents used citation management programs to collaborate and turned to the library for training and support.  相似文献   
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Introduction

Glycosylated hemoglobin (HbA1c) concentrations measured in clinical chemistry laboratories show large differences between their interlaboratory reported values. Laboratory measurements of quality performance should be based on quantitative data. The sigma metrics model provides an objective method for the assessment of current HbA1c assays and is useful in quality management planning. The aim of our study was to evaluate the analytical performance of the MQ-2000 PT HbA1c analyzer test results in the context of our operating conditions on the sigma scale.

Materials and methods

The coefficient of variation was determined from the calculated mean and standard deviation evaluated from internal quality control (QC) (N = 168 days) (Shanghai Huachen Biological Reagent Co. Ltd, China) data, and records of external quality data (KBUDEK, İstanbul, Turkey) measured in the period from May to November 2013 were used to determine the bias. The resulting data and total allowable error rate (TEA = 10%) from the Clinical Laboratory Improvement Amendments of 1988 (CLIA’88) were used to calculate the sigma level.

Results

The calculated coefficient of variations (CVs) at the two levels, normal (QC1 = 36.6 ± 2.38 mmol/mol) and pathological (QC2 = 84.7 ± 2.68 mmol/mol), were 6.5% and 3.1%, respectively. The average bias between the external QC and MQ-2000 PT during the study period was 4.3%. The calculated average sigma value was 1.19.

Conclusions

The MQ-2000 PT HbA1c is a new analyser in the market; there is need for improvement and the method should be controlled with greater attention to ensure quality.Key words: diabetes mellitus, hemoglobin A1c protein, human, chromatography, high pressure liquid chromatography  相似文献   
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The current paper considers how children spend their time in state-funded pre-kindergarten programs and how time use relates to ethnicity, gender, and family income, based on the assumption that how time is spent in pre-kindergarten is relevant for the programs’ success in narrowing achievement gaps. Classroom observations of 2061 children in 652 pre-k programs in 11 states were analyzed. Findings indicated that the pre-kindergarten day was roughly equally divided among free choice, teacher-assigned activities, and meals/routines. Children spent much of their time in language/literacy, social studies, and art, and less time in math and gross motor activities. Much of the pre-k day was spent in ‘no coded learning activity.’ Children in classes with lower proportions of Latino and African American children and higher average income-to-need ratios were generally engaged in richer and more stimulating experiences. The child-level variables of ethnicity and income were generally unrelated to how children spent their time, above and beyond the effects of classroom-level ethnicity and income. There were generally small, but significant gender differences – always in the gender-stereotyped direction – in how time was spent, especially during free choice time.  相似文献   
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