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81.
Research Findings: Public policy has increasingly focused on expansion of preschool access for underserved students and systematic evaluation of preschool quality and students’ readiness for school. However, such evaluation is limited by a lack of thoroughly validated assessments for use with preschool populations. The present study examined the measurement and structural invariance of the Kindergarten Student Entrance Profile (KSEP) across kindergarten and prekindergarten groups to evaluate its potential use across developmental groups. Participants included 522 kindergarten and 548 prekindergarten students in central California. Invariance was tested by fitting a series of multiple-groups confirmatory factor analysis models with parameter constraints across groups. Results indicated that measurement and structural parameters of the KSEP were invariant across kindergarten and prekindergarten groups. Prekindergarten means on both Social–Emotional Readiness and Cognitive Readiness were significantly lower than kindergarten means. Practice or Policy: These results suggest that the KSEP may potentially be used with prekindergarten students to assess school readiness and inform intervention before kindergarten entry. 相似文献
82.
Persons with Mental Illness (PMIs) require unique consideration and individualized attention in the criminal justice system. Research has demonstrated the prevalence with which police come into contact with these individuals, the unique considerations made by courtrooms serving PMIs, the overrepresentation of PMIs in correctional settings, and the problems PMIs experience when reentering the community from incarceration. Given the growth of attention to this area, and the increased reality of challenges that criminal justice professionals encounter when working with PMIs, this paper explores the prevalence of courses on mental illness in criminal justice undergraduate programs in the United States. The current review of over 640 curricula in the United States illustrates that courses devoted solely to the topic of mental illness in the criminal justice system are particularly rare. The importance of offering more courses in the interface between mental illness and criminal justice for future professionals in the field is discussed. 相似文献
83.
The study builds on a newly modified Technology Acceptance Model (TAM) to substantiate the motivation and operation of teachers’ utilization of online learning resources. A ‘Comprehensiveness’ construct is proposed in the modified TAM to reflect the breadth and depth of rich online knowledge. This new construct serves as the mediator between ‘Usefulness’ and ‘Behavioral Intention’ in the new TAM structure. In addition, the ‘Ease of Use’ factor in conventional TAM is proposed to moderate the mediation in the modified TAM. Survey data are collected from 301 teachers undertaking certified training in Macau and Structural Equation Model (SEM) technique is used to assess the model. Moderated mediation is evaluated using both multi-group bootstrapping method and moderated path analysis method. Both methods verify the presence of moderated mediation with partial mediation in high Ease of Use values and full mediation in low Ease of Use values. Theoretical implication of the current study extends the coverage of TAM applications and academic implication suggests the strengthening in teachers’ professional development and government sponsorship in building repositories of online resources. 相似文献
84.
Matthew T. McCrudden 《Instructional Science》2011,39(6):865-879
This study examined whether specific relevance instructions affect transfer appropriate processing. Undergraduates (n = 52) were randomly assigned to one of three pre-reading question conditions that asked them what-questions, why-questions,
or to read for understanding (i.e., control condition). There were no differences in reading time across conditions for sentences
targeted by the pre-reading questions. There were three main findings with respect to cued recall. First, participants in
the experimental conditions did better on questions that had greater similarity to relevance instructions than questions that
had lesser similarity to relevance instructions. Second, participants in the experimental conditions did better on questions
that had greater similarity to relevance instructions than the participants in the other conditions on those same questions.
Third, participants in the control condition recalled equal amounts of information for both question. The results suggest
that specific relevance instructions promote transfer appropriate processing and affect the quality of memory for text. 相似文献
85.
Matthew P. Ciszek 《The Journal of Academic Librarianship》2011,37(5):430-436
This article explores the relationship between the perceived campus environment for gay, lesbian, bisexual, and transgender (GLBT) students at colleges and universities and how academic libraries have deployed GLBT-related resources on the Web. Recommendations are made for increasing GLBT-related materials and information in academic libraries. 相似文献
86.
Bernard J. Jansen Zhe Liu Courtney Weaver Gerry Campbell Matthew Gregg 《Information processing & management》2011
Real time search is an increasingly important area of information seeking on the Web. In this research, we analyze 1,005,296 user interactions with a real time search engine over a 190 day period. Using query log analysis, we investigate searching behavior, categorize search topics, and measure the economic value of this real time search stream. We examine aggregate usage of the search engine, including number of users, queries, and terms. We then classify queries into subject categories using the Google Directory topical hierarchy. We next estimate the economic value of the real time search traffic using the Google AdWords keyword advertising platform. Results shows that 30% of the queries were unique (used only once in the entire dataset), which is low compared to traditional Web searching. Also, 60% of the search traffic comes from the search engine’s application program interface, indicating that real time search is heavily leveraged by other applications. There are many repeated queries over time via these application program interfaces, perhaps indicating both long term interest in a topic and the polling nature of real time queries. Concerning search topics, the most used terms dealt with technology, entertainment, and politics, reflecting both the temporal nature of the queries and, perhaps, an early adopter user-based. However, 36% of the queries indicate some geographical affinity, pointing to a location-based aspect to real time search. In terms of economic value, we calculate this real time search stream to be worth approximately US $33,000,000 (US $33 M) on the online advertising market at the time of the study. We discuss the implications for search engines and content providers as real time content increasingly enters the main stream as an information source. 相似文献
87.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty. 相似文献
88.
Jyoti P. Gurung Moein Navvab Kashani Sanaz Agarwal Gonzalo Peralta Murat Gel Matthew A. B. Baker 《Biomicrofluidics》2021,15(3)
Many motile bacteria are propelled by the rotation of flagellar filaments. This rotation is driven by a membrane protein known as the stator-complex, which drives the rotor of the bacterial flagellar motor. Torque generation is powered in most cases by proton transit through membrane protein complexes known as stators, with the next most common ionic power source being sodium. Sodium-powered stators can be studied through the use of synthetic chimeric stators that combine parts of sodium- and proton-powered stator proteins. The most well studied example is the use of the sodium-powered PomA-PotB chimeric stator unit in the naturally proton-powered Escherichia coli. Here we designed a fluidics system at low cost for rapid prototyping to separate motile and non-motile populations of bacteria while varying the ionic composition of the media and thus the sodium-motive force available to drive this chimeric flagellar motor. We measured separation efficiencies at varying ionic concentrations and confirmed using fluorescence that our device delivered eightfold enrichment of the motile proportion of a mixed population. Furthermore, our results showed that we could select bacteria from reservoirs where sodium was not initially present. Overall, this technique can be used to implement the selection of highly motile fractions from mixed liquid cultures, with applications in directed evolution to investigate the adaptation of motility in bacterial ecosystems. 相似文献
89.
Many household consumables contain volatile organic compounds(VOCs)as the active ingredient.Long term exposure to VOCs could cause various health problems,especially to the respiratory system.Graphene has attracted a lot of attention recently for its potential to be used as sensing material for VOCs.In this project we have constructed graphene/PVA composite based gas sensors for VOC detection.It was perceived that the polymer could introduce better selectivity to the sensor.Results suggest that the proposed sensor is highly sensitive to low molecular weight VOCs and that the manner in which the sensor respond to the vapour depends on the polarity or hydrophobicity of the vapour. 相似文献
90.
‘Chinese’ is an ambiguous term, depending on whether it is taken to describe a political, linguistic, or cultural entity. While the term has often been considered to represent a politically and culturally homogeneous national identity in recent decades, this article aims to challenge this notion by examining the characteristics and practices of nationalistic education in Hong Kong since 1945. It explores how national identity has been interpreted by different Chinese states over time through different educational policies and practices. Focusing on the evolution of nationalistic education in three phases, this article presents a detailed account and analyses different nationalist narratives over six decades. It describes how different political forces define themselves and come to terms with what are often dual or competing national identities. Historical examples illustrate the challenges in policies and practices of nationalistic education. 相似文献