Using query logs to establish vocabularies in distributed information retrieval

Users of search engines express their needs as queries, typically consisting of a small number of terms. The resulting search engine query logs are valuable resources that can be used to predict how people interact with the search system. In this paper, we introduce two novel applications of query logs, in the context of distributed information retrieval. First, we use query log terms to guide sampling from uncooperative distributed collections. We show that while our sampling strategy is at least as efficient as current methods, it consistently performs better. Second, we propose and evaluate a pruning strategy that uses query log information to eliminate terms. Our experiments show that our proposed pruning method maintains the accuracy achieved by complete indexes, while decreasing the index size by up to 60%. While such pruning may not always be desirable in practice, it provides a useful benchmark against which other pruning strategies can be measured.     

Professors and examinations: ideas of the university in nineteenth-century Scotland

The separation of examining from teaching, pushed furthest in the ‘examining university’ of which London University, founded in 1836, was the model, was a much-debated principle in nineteenth-century Britain. This separation was generally rejected in Scotland, but only after complex controversies that illustrate how Scots defined their university tradition in comparative terms, and how Scottish developments interacted with those in England and Ireland. Among the issues involved were proposals for a National University or central examining board, and claims that graduates should have a right to give ‘extramural’ teaching in competition with professors. The paper traces this aspect of university reform in Scotland from the 1820s to the 1890s, and argues that the professorial model and the integration of teaching and examining were successfully consolidated and defended.     

Deconstructing Cumulative Risk: Poverty and Aspects of Instability Relate Uniquely to Young Children’s Basal Cortisol

This study deconstructs cumulative risk to probe unique relations to basal cortisol for family income and four distinct aspects of poverty-related instability. Participants were 288 children aged 3–5 years who attended Head Start preschool. Parents reported on poverty risks. Children provided samples of salivary cortisol at four times of day on 6 days. Results of hierarchical linear modeling with piecewise latent growth curves representing basal cortisol indicated unique relations for family income, household chaos, neighborhood risk, attachment-disruptive residential changes, and non-attachment changes. The findings support an equifinality implied by cumulative risk models in demonstrating that multiple risks relate to cortisol dysregulation yet also suggest the utility of considering unique effects of different risks for neurophysiological stress response functioning.     

Exploring the mathematical and interpretative strategies of Maxwell's Treatise on Electricity and Magnetism

James Clerk Maxwell's Treatise on Electricity and Magnetism forms one of the major scientific texts of the 19th century, describing the phenomena of electricity and magnetism and the interaction between them. The sources Maxwell acknowledged as the inspiration for his own approach were the Englishman Michael Faraday and his fellow Scotsman William Thomson (later Lord Kelvin). In the Treatise Maxwell presents an approach he maintains was equivalent mathematically to the well established Continental electromagnetism but focused on an action via a medium approach to electromagnetism and located within a British experimental tradition. Exploring these features reveals the Treatise to be in accord with other deep themes in Maxwell's writings, which ground him intellectually and personally in the world of 19th century British Natural Philosophy.     

Clay Modelling and Social Modelling: effects of interactive teaching on young children's creative artmaking

In this project, 28 6‐year‐olds were taught skills involved in artistic claywork using principles of social modelling and cognitive learning in a classroom situation, over a series of six lessons. A further 28 students, serving as controls, were taught according to the normal art curriculum. The students’ clay models were photographed on pre‐test and post‐test, and rated by three expert judges (professional artists familiar with children's artwork) blind to treatment conditions. The cognitive social learning group evidenced strong gains on measures of creativity as defined by approximation to a three‐dimensional form, technical competency, decorative competency and aesthetic appeal. The control group students failed to evidence any significant change in rated creativity.     

Regulating off-centering distortion maximizes photoluminescence in halide perovskites

Metal halide perovskites possess unique atomic and electronic configurations that endow them with high defect tolerance and enable high-performance photovoltaics and optoelectronics. Perovskite light-emitting diodes have achieved an external quantum efficiency of over 20%. Despite tremendous progress, fundamental questions remain, such as how structural distortion affects the optical properties. Addressing their relationships is considerably challenging due to the scarcity of effective diagnostic tools during structural and property tuning as well as the limited tunability achievable by conventional methods. Here, using pressure and chemical methods to regulate the metal off-centering distortion, we demonstrate the giant tunability of photoluminescence (PL) in both the intensity (>20 times) and wavelength (>180 nm/GPa) in the highly distorted halide perovskites [CH₃NH₃GeI₃, HC(NH₂)₂GeI₃, and CsGeI₃]. Using advanced in situ high-pressure probes and first-principles calculations, we quantitatively reveal a universal relationship whereby regulating the level of off-centering distortion towards 0.2 leads to the best PL performance in the halide perovskites. By applying this principle, intense PL can still be induced by substituting CH₃NH₃⁺ with Cs⁺ to control the distortion in (CH₃NH₃)_1-xCs_xGeI₃, where the chemical substitution plays a similar role as external pressure. The compression of a fully substituted sample of CsGeI₃ further tunes the distortion to the optimal value at 0.7 GPa, which maximizes the emission with a 10-fold enhancement. This work not only demonstrates a quantitative relationship between structural distortion and PL property of the halide perovskites but also illustrates the use of knowledge gained from high-pressure research to achieve the desired properties by ambient methods.     

The Use of Health Related Quality of Life Measurement in Cardiovascular and Pulmonary Physical Therapy Practice: An Exploratory Study

Background: The American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR) recommends health related quality of life (HRQL) measurement with all cardiovascular and pulmonary patients. The current pattern of use of HRQL measurement among cardiovascular and pulmonary physical therapists is unknown. Objective: The purpose of this study was to evaluate the pattern of use of HRQL measurement among cardiovascular and pulmonary physical therapists. Design: The study used a semi-structured interview format within the context of 3 focus groups. Methods: Eleven physical therapists participated in this study and all were members of the Cardiovascular and Pulmonary Section of the American Physical Therapy Association (APTA). Participants participated in a conference call and were provided a question tree to guide discussion. Results: Several primary themes emerged, including decreased knowledge, barriers, and poor indicators of patient status. In addition, several subthemes developed including lack of familiarity, lack of use, administrative and cost limitations, inappropriateness of tool for patient population, correlation between function and quality of life, and suggestions for future outcome measures. Conclusions: A lack of familiarity and use of HRQL measurement and barriers to their use were established. In addition, ideas for future research on HRQL measurements with specific patient populations in physical therapy practice were defined.Key Words: health related quality of life, outcomes measurement     

Principles of Integrated Instruction for Engagement in Reading

Our purpose in this article is to propose a set of design principles to serve as a structural framework for enhancing engagement in reading. We provide a rationale for our emphasis on engagement, which we believe is an important aim of reading instruction. We discuss the sources of the proposed design principles. These design principles consist of a set of features of the classroom context including: conceptual themes, real-world interactions, self-direction, interesting texts, social collaboration, self-expression, cognitive strategy instruction, time for engaged reading, and coherence. We present empirical support from the educational psychology literature for each principle. For illustration, we provide a brief depiction of each principle functioning within a framework of Concept-Oriented Reading Instruction (CORI). We emphasize that each principle is dependent on several others, and we describe how the functioning of each principle is contingent on the occurrence of several affiliated principles in the vignettes of CORI.