Exploiting Manual Indexing to Improve Collection Selection and Retrieval Effectiveness

Vocabulary incompatibilities arise when the terms used to index a document collection are largely unknown, or at least not well-known to the users who eventually search the collection. No matter how comprehensive or well-structured the indexing vocabulary, it is of little use if it is not used effectively in query formulation. This paper demonstrates that techniques for mapping user queries into the controlled indexing vocabulary have the potential to radically improve document retrieval performance. We also show how the use of controlled indexing vocabulary can be employed to achieve performance gains for collection selection. Finally, we demonstrate the potential benefit of combining these two techniques in an interactive retrieval environment. Given a user query, our evaluation approach simulates the human user's choice of terms for query augmentation given a list of controlled vocabulary terms suggested by a system. This strategy lets us evaluate interactive strategies without the need for human subjects.     

The transition to college: Diverse students,diverse stories

While much is known about the role of student involvement in various dimensions of student change and development, considerably less is known abouthow students become involved as they make the transition from work or high school to college. This paper describes the results of a series of focus-group interviews with 132 diverse, new students entering a community college; a liberal arts college; an urban, commuter, comprehensive university; and a large research university. The study identifies the people, experiences, and themes in the processes through which students become (or fail to become) members of the academic and social communities on their campus. The research reported here was conducted under the auspices of the National Center on Postsecondary Teaching, Learning, and Assessment. NCTLA is funded by the U.S. Department of Education, Office of Educational Research and Improvement (OERI), under Grant No. R117G10037. The opinions herein do not necessarily reflect the position or policies of OERI, and no official endorsement should be inferred. Presented at the 1993 AIR Forum, Chicago, May 1993.     

Maternal Supportive Behavior,Cognitive Talk,and Desire/Emotion Talk at 24 Months: Distinct Factors and Differential Antecedents

Objective. Mental-state talk is an important aspect of parenting, but it is not clear whether this type of talk is structurally distinct from behavioral support or sensitivity. Although assessment of sensitive, supportive behavior captures a mother’s responses to her child’s needs, mental-state talk assesses a mother’s consideration of (and comments on) her child’s inner world. This study examined the structure and antecedents of mental-state talk, behavioral support, and sensitivity. Design. Data from the NICHD Study of Early Child Care and Youth Development were used, and mothering was assessed during a laboratory session when children were 24 months old (N = 1114). Results. Confirmatory factor analyses provided support for the hypothesized three-factor model, in which maternal supportive behavior, cognitive talk, and desire/emotion talk formed distinct factors. Furthermore, maternal depressive symptoms assessed at 1 and 6 months predicted less supportive behavior, whereas traditional parenting beliefs assessed at 1 month predicted lower levels of all three mothering outcomes. Conclusion. Maternal talk about mental states is a unique component of parenting, and cognitive talk is distinct from desire and emotion talk.     

Toward a rhetorical theory of deixis

This article advances a rhetorical theory of deixis, a theoretical and methodological orientation that infuses the linguistic concept of deixis with rhetorical understandings of ethos, place, and time. Deixis reveals the rhetorical dynamics within the fabric of spoken discourse, dynamics that often refer to what is outside the text to make sense of what is within it. Ultimately, I argue that identifying the deictic indicators within a speech text enables the critic to pinpoint where, how, and why a speaker activates the physical elements of the speech situation as a material means of persuasion. After outlining the theoretical tenets of this approach, I analyze Harry S. Truman's Address to the National Association for the Advancement of Colored People on June 29, 1947, to show how a rhetorical theory of deixis orients the critic to the bodies, places, and temporalities implied in and displayed through speech.     

如何适应高中生活

即将升入高中的同学们一定对紧张而丰富多彩的高中生活充满着美好的憧憬,然而,当你跨入高中大门时,你将会遇到各种以前没碰到过的学习、生活中的问题和困惑。那么怎样才能适应高中生活呢?本文作者就以美国高中过来人的身份给即将进入高中的朋友们提供了10条建议,虽然国情不同,但相信你也一定会从中有所收获。     

Quality Management Procedures Influence the Food Safety Practices at Childcare Centers

Childcare in the United States (US) has become a necessary part of life for most working parents with the increased use of center-based childcare over the past three decades. Approximately 13 million preschoolers attend some form of childcare. Literature indicates the main predictors of quality childcare programs are adequate experience and specialized training of childcare staff. A growing concern among researchers, however, is the limited training among childcare professionals in the area of food safety. Children have minimal control of food safety risks because other people prepare their meals. A questionnaire was developed and mailed to childcare center directors in Texas and Iowa to identify the demographic, food safety and other practices that influence the training and decisions made by childcare center directors. Results indicate the need of continual management and food safety training for both directors and staff in order to provide a safe environment for young children.     

Mastery motivation and expressive language in young children with hearing loss

We studied the relation between mastery motivation and expressive language in 200 young children with hearing loss. Hearing mothers assessed their children's expressive language (Minnesota Child Development Inventory; Ireton & Thwing, 1974) and several aspects of mastery motivation including mastery pleasure and three components of mastery persistence (gross motor, object oriented, and social/symbolic) using the Dimensions of Mastery Motivation Questionnaire (Morgan et al., 1992). Simple correlations revealed significant relations between expressive language and all mastery motivation scales. When demographic and hearing loss variables were entered into a regression equation, only increased social/symbolic persistence was significantly related to, and increased object-oriented persistence was marginally related to, increases in expressive language quotients. Expressive language quotients also increased significantly as child age and degree of hearing loss decreased and as mothers' ratings of their child's general competence increased. In addition, decreases in the age at which the child was enrolled in intervention were marginally related to increases in expressive language quotients (f =.06).     

Tactile,maternal, and pharmacologic factors involved in the “transport response” in rat pups

A series of eight experiments was run to characterize the potentiation of the transport response reported with tactile stimulation. Experiments 1A–C were designed to investigate the types of tactile stimulation that could potentiate an initially weak transport response. Experiments 2A–C were designed to assess the effect of maternal/littermate deprivation on responsiveness to external stimuli in 9- and 16-day-old rat pups. Experiments 3A and 3B were designed to investigate, pharmacologically, underlying mechanisms for the transport response potentiation effect. It was found that if the initial stimulus in producing a strong transport response is inadequate, additional tactile stimulation can potentiate the response. The additional stimuli work best if they are diffuse, if discrete inputs can summate over areas, or if they encompass the snout area. It also was found that isolation could lead to increased responsiveness to stimuli normally eliciting or potentiating the response in 9- and 16-day-old rats. Finally, results indicate that both dopaminergic and beta-noradrenergic systems are important in the response potentiation seen with maternal/littermate deprivation.     

The amazingly patient tutor: students' interactions with an online carbohydrate chemistry course

Many multimedia chemistry courses fail to reach their full educational potential as they do not engage the learner in a meaningful task or give appropriate feedback. Though molecular modelling is a recognised technique widely used in chemistry to enable students to grasp difficult concepts, tutorials often do not afford students either the time or scope to learn by experimenting with molecular structures. In this paper we describe the educational development of a web based organic chemistry tutorial which aims to enable students to learn chemical concepts through the manipulation of structural formulae and the provision of appropriate feedback. An online chemical structure modelling tool was developed to enable molecules to be drawn online and to provide feedback. The aim of this study is to address key issues relevant to the development of educational resources of this nature. It will be of particular interest to teachers and lecturers working within Science and Engineering, audio–visual staff and educational developers.     

Integrating PCR theory and bioinformatics into a research-oriented primer design exercise

Polymerase chain reaction (PCR) is a conceptually difficult technique that embodies many fundamental biological processes. Traditionally, students have struggled to analyze PCR results due to an incomplete understanding of the biological concepts (theory) of DNA replication and strand complementarity. Here we describe the design of a novel research-oriented exercise that prepares students to design DNA primers for PCR. Our exercise design includes broad and specific learning goals and assessments of student performance and perceptions. We developed this interactive Primer Design Exercise using the principles of scientific teaching to enhance student understanding of the theory behind PCR and provide practice in designing PCR primers to amplify DNA. In the end, the students were more poised to troubleshoot problems that arose in real experiments using PCR. In addition, students had the opportunity to utilize several bioinformatics tools to gain an increased understanding of primer quality, directionality, and specificity. In the course of this study many misconceptions about DNA replication during PCR and the need for primer specificity were identified and addressed. Students were receptive to the new materials and the majority achieved the learning goals.