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Key Insights (key + insight)

Distribution by Scientific Domains

Humanities and Social Sciences	30%
Medical Sciences	15%
Life Sciences	15%
Business, Economics, Finance and Accounting	15%

Selected Abstracts

Viability of Auction-Based Revenue Management in Sequential Markets

DECISION SCIENCES, Issue 2 2005
Tim Baker
ABSTRACT The Internet is providing an opportunity to revenue management practitioners to exploit the potential of auctions as a new price distribution channel. We develop a stochastic model for a high-level abstraction of a revenue management system (RMS) that allows us to understand the potential of incorporating auctions in revenue management in the presence of forecast errors associated with key parameters. Our abstraction is for an environment where two market segments book in sequence and revenue management approaches consider auctions in none, one, or both segments. Key insights from our robust results are (i) limited auctions are best employed closest to the final sale date, (ii) counterbalancing forecast errors associated with overall traffic intensity and the proportion of customer arrivals in a segment is more important if an auction is adopted in that segment, and (iii) it is critically important not to err on the side of overestimating market willingness to pay. [source]

Timing and nature of late Quaternary mountain glaciation,

JOURNAL OF QUATERNARY SCIENCE, Issue 6-7 2008
Glenn D. Thackray
Abstract Compilations of regional- to subcontinental-scale mountain glacier chronologies from five continents, plus Hawaii, examine the temporal and spatial patterns of mountain glaciation. The compilations yield key insights into the nature of past fluctuations in temperature and precipitation in mountains and adjacent regions, and provide baseline data for examining the dynamics of glacier responses to climate change. Key insights from these compilations include the wide variability of glacier responses to fluctuations in insolation, temperature and precipitation and the regionally specific variations in climatic variables through late Quaternary time. The compilations highlight the need to improve the density and quality of geochronological data and to enhance the understanding of the links between climate and glaciation. Copyright © 2008 John Wiley & Sons, Ltd. [source]

An Optimizing Compiler for Automatic Shader Bounding

COMPUTER GRAPHICS FORUM, Issue 4 2010
Petrik Clarberg
Abstract Programmable shading provides artistic control over materials and geometry, but the black box nature of shaders makes some rendering optimizations difficult to apply. In many cases, it is desirable to compute bounds of shaders in order to speed up rendering. A bounding shader can be automatically derived from the original shader by a compiler using interval analysis, but creating optimized interval arithmetic code is non-trivial. A key insight in this paper is that shaders contain metadata that can be automatically extracted by the compiler using data flow analysis. We present a number of domain-specific optimizations that make the generated code faster, while computing the same bounds as before. This enables a wider use and opens up possibilities for more efficient rendering. Our results show that on average 42,44% of the shader instructions can be eliminated for a common use case: single-sided bounding shaders used in lightcuts and importance sampling. [source]

Insights into drug metabolism by cytochromes P450 from modelling studies of CYP2D6-drug interactions

BRITISH JOURNAL OF PHARMACOLOGY, Issue S1 2008
J-D Maréchal
The cytochromes P450 (CYPs) comprise a vast superfamily of enzymes found in virtually all life forms. In mammals, xenobiotic metabolizing CYPs provide crucial protection from the effects of exposure to a wide variety of chemicals, including environmental toxins and therapeutic drugs. Ideally, the information on the possible metabolism by CYPs required during drug development would be obtained from crystal structures of all the CYPs of interest. For some years only crystal structures of distantly related bacterial CYPs were available and homology modelling techniques were used to bridge the gap and produce structural models of human CYPs, and thereby obtain useful functional information. A significant step forward in the reliability of these models came seven years ago with the first crystal structure of a mammalian CYP, rabbit CYP2C5, followed by the structures of six human enzymes, CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2D6 and CYP3A4, and a second rabbit enzyme, CYP2B4. In this review we describe as a case study the evolution of a CYP2D6 model, leading to the validation of the model as an in silico tool for predicting binding and metabolism. This work has led directly to the successful design of CYP2D6 mutants with novel activity,including creating a testosterone hydroxylase, converting quinidine from inhibitor to substrate, creating a diclofenac hydroxylase and creating a dextromethorphan O -demethylase. Our modelling-derived hypothesis-driven integrated interdisciplinary studies have given key insight into the molecular determinants of CYP2D6 and other important drug metabolizing enzymes. British Journal of Pharmacology (2008) 153, S82,S89; doi:10.1038/sj.bjp.0707570; published online 19 November 2007 [source]

Problem gamblers share deficits in impulsive decision-making with alcohol-dependent individuals

ADDICTION, Issue 6 2009
Andrew J. Lawrence
ABSTRACT Aims Problem gambling has been proposed to represent a ,behavioural addiction' that may provide key insights into vulnerability mechanisms underlying addiction in brains that are not affected by the damaging effects of drugs. Our aim was to investigate the neurocognitive profile of problem gambling in comparison with alcohol dependence. We reasoned that shared deficits across the two conditions may reflect underlying vulnerability mechanisms, whereas impairments specific to alcohol dependence may reflect cumulative effects of alcohol consumption. Design Cross-sectional study. Setting Out-patient addiction treatment centres and university behavioural testing facilities. Participants A naturalistic sample of 21 male problem and pathological gamblers, 21 male alcohol-dependent out-patients and 21 healthy male control participants. Measurements Neurocognitive battery assessing decision-making, impulsivity and working memory. Findings The problem gamblers and alcohol-dependent groups displayed impairments in risky decision-making and cognitive impulsivity relative to controls. Working memory deficits and slowed deliberation times were specific to the alcohol-dependent group. Conclusions Gambling and alcohol-dependent groups shared deficits in tasks linked to ventral prefrontal cortical dysfunction. Tasks loading on dorsolateral prefrontal cortex were selectively impaired in the alcohol-dependent group, presumably as a consequence of long-term alcohol use. [source]

The work of women teachers in primary literacy education: knowing and doing

ENGLISH IN EDUCATION, Issue 2 2007
Barbara Comber
Abstract This paper provides a retrospective account of three decades of my work as a literacy educator and researcher. Taking key insights from feminist sociologist, Dorothy Smith, including women's standpoint, the everyday world as problematic, institutional capture, a sociology for the people, I revisit my research on literacy, poverty and schooling. I argue that understanding better the effects of what we do in educational institutions, through collaborative research with teachers, can lead us to generate positive alternative equity-driven practices. [source]

Interplay of actors, scales, frameworks and regimes in the governance of biodiversity

ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 3 2009
Jouni Paavola
Abstract This article examines the key contributions of the political science and systems theory based literatures on environmental governance, and uses them to analyse the governance of biodiversity in Europe. The article suggests that the key insights of the two bodies of literature are a distinction between governance frameworks and regimes on one hand, and the importance of multifaceted and multiple scales on the other. These key insights draw attention to horizontal and vertical forms of interplay. The article suggests that interplay, both between actors and levels and between frameworks and regimes, is ubiquitous and ambivalent: it can either foster or hinder environmental governance. The article illustrates this discussion in the context of governance of biodiversity in Europe, highlighting how vertical and horizontal interplay between the governance framework for biodiversity and the broader institutional setting or regime have characterized the implementation of the Habitats Directive, both complicating and fostering the governance of biodiversity in Europe. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment. [source]

The organization of visual object representations: a connectionist model of effects of lesions in perirhinal cortex

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2002
Timothy J. Bussey
Abstract We have developed a simple connectionist model based on the idea that perirhinal cortex has properties similar to other regions in the ventral visual stream, or ,what' pathway. The model is based on the assumption that representations in the ventral visual stream are organized hierarchically, such that representations of simple features of objects are stored in caudal regions of the ventral visual stream, and representations of the conjunctions of these features are stored in more rostral regions. We propose that a function of these feature conjunction representations is to help to resolve ,feature ambiguity', a property of visual discrimination problems that can emerge when features of an object predict a given outcome (e.g. reward) when part of one object, but predict a different outcome when part of another object. Several recently reported effects of lesions of perirhinal cortex in monkeys have provided key insights into the functions of this region. In the present study these effects were simulated by comparing the performance of connectionist networks before and after removal of a layer of units corresponding to perirhinal cortex. The results of these simulations suggest that effects of lesions in perirhinal cortex on visual discrimination may be due not to the impairment of a specific type of learning or memory, such as declarative or procedural, but to compromising the representations of visual stimuli. Furthermore, we propose that attempting to classify perirhinal cortex function as either ,perceptual' or ,mnemonic' may be misguided, as it seems unlikely that these broad constructs will map neatly onto anatomically defined regions of the brain. [source]

Timing and nature of late Quaternary mountain glaciation,

Cryptic diversity and patterns of host specificity in trematode flatworms

MOLECULAR ECOLOGY, Issue 13 2010
ALEXANDER HAYWARD
The widespread utilization of molecular markers has revealed that a broad spectrum of taxa contain sets of morphologically cryptic, but genetically distinct lineages (Bickford et al. 2007). The identification of cryptic taxa is important as an accurate appreciation of diversity is crucial for a proper understanding of evolutionary and ecological processes. An example is the study of host specificity in parasitic taxa, where an apparent generalist may be found to contain a complex of several more specific species (Smith et al. 2006). Host specificity is a key life history trait that varies greatly among parasites (Poulin & Keeney 2007). While some can exploit a wide range of hosts, others are confined to just a single species. Access to additional hosts increases the resources available to a parasite. However, physiological or ecological constraints can restrict the extension of host range. Furthermore, there may be a trade-off between relaxed specificity and performance: generalism can decrease a parasites ability to adapt to each individual host species, and increase exposure to competition from other parasites (Poulin 1998). Despite the central role that host specificity plays in parasite life history, relatively little is known about how host range is determined in natural systems, and data from field studies are required to evaluate among competing ideas. In this issue, an exciting paper by Locke et al. (2010) makes a valuable contribution toward the understanding of host specificity in an important group of trematode flatworms. Using molecular methods, Locke et al. reveal an almost four-fold increase in the appreciated diversity of their focal group. In combination with a large and elegant sampling design this allows them to accurately assess host specificity for each taxon, and thus draw key insights into the factors that control host range in a dominant parasite group. [source]

DOE genomics: Applications to in situ subsurface bioremediation

REMEDIATION, Issue 1 2006
Robert T. AndersonArticle first published online: 22 DEC 200
Microbial communities can greatly affect the mobility and fate of subsurface contaminants, yet relatively little is known about the functioning of microorganisms in subsurface environments. Major advances in DNA sequencing capability and the advent of genome-enabled studies have produced key insights into how microorganisms adapt to environmental conditions and/or biotransform subsurface contaminants starting from analyses of genome content. These techniques enable the researcher to detect how an organism responds to its environment and, potentially, to devise better methods to promote specific microbial activity in subsurface environments. The U.S. Department of Energy sponsors genome research through the Genomics:GTL program. One of the applications of this research is to better understand and control biological processes influencing the mobility of contaminants of concern to DOE such as metals and radionuclides. Genome and gene expression techniques have led to new insights into the functioning of subsurface microbial communities, but the true potential of these techniques is still to be revealed. As genome-enabled science progresses, techniques for evaluating gene expression patterns of whole communities will advance the understanding and development of optimized in situ bioremediation and more realistic simulations of microbial contaminant biotransformation. © 2006 Wiley Periodicals, Inc.* [source]

Perspective: Economic Conditions, Entrepreneurship, First-Product Development, and New Venture Success,

THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 1 2010
Lisa Z. Song
Entrepreneurial ventures have a significant impact on new job creation and economic growth, but existing evidence indicates that most entrepreneurial ventures fail. This paper reports key insights from VENSURV, a new database that tracks the success and failure of ventures founded since 1998. Based on an analysis of 539 new ventures founded during the years 1991,2001, the following conclusions are reached. First, consistent with prior research, less than half of the 539 ventures survived more than two years. Second, economic downturns lead to higher failure rates for new ventures. Third, new venture success is highly correlated with first-product success. Fourth, first-product success is enhanced when those products are introduced into markets with emerging market needs but with established industry standards. Finally, first-product and venture performance are significantly higher for products based on ideas that came from the founders. In addition, the most successful first products are based on ideas that reflect both technology development and an analysis of customer needs. [source]

Bodies for Rent: Labor and Marginality in Southern Louisiana

ANTHROPOLOGY OF WORK REVIEW, Issue 3 2005
Rylan Higgins
Abstract In southern Louisiana, supplying a workforce for the offshore oil and gas industry's least desirable jobs requires manipulation of non-market forces that shape access to labor. Specifically, a labor camp system, evolving since the late 1970s, recruits and deploys disempowered workers (or "bodies") to fulfill the manual labor needs of a wide variety of oil and gas companies,a process that generates profits for the individuals who own labor camps while reproducing the continuities between work and poverty for the marginalized underclass of US cities. This essay explores the perpetuation of the camp system, arguing that it is not company desires for cost-saving mechanisms but demands for a tractable workforce that explain the primary relationships between camp workers, managers and owners, on the one hand, and oil company management, on the other. Understandings of how social capital, cultural capital and drug dependency factor into employment at one camp provide key insights into the anatomy of the labor camp system. [source]