Showing papers by "Brigham Young University published in 2012"

Improving long-term outcomes after discharge from intensive care unit: report from a stakeholders' conference.

Abstract: Background:Millions of patients are discharged from intensive care units annually. These intensive care survivors and their families frequently report a wide range of impairments in their health status which may last for months and years after hospital discharge.Objectives:To report on a 2-day Socie

Cross-biome metagenomic analyses of soil microbial communities and their functional attributes

Abstract: For centuries ecologists have studied how the diversity and functional traits of plant and animal communities vary across biomes. In contrast, we have only just begun exploring similar questions for soil microbial communities despite soil microbes being the dominant engines of biogeochemical cycles and a major pool of living biomass in terrestrial ecosystems. We used metagenomic sequencing to compare the composition and functional attributes of 16 soil microbial communities collected from cold deserts, hot deserts, forests, grasslands, and tundra. Those communities found in plant-free cold desert soils typically had the lowest levels of functional diversity (diversity of protein-coding gene categories) and the lowest levels of phylogenetic and taxonomic diversity. Across all soils, functional beta diversity was strongly correlated with taxonomic and phylogenetic beta diversity; the desert microbial communities were clearly distinct from the nondesert communities regardless of the metric used. The desert communities had higher relative abundances of genes associated with osmoregulation and dormancy, but lower relative abundances of genes associated with nutrient cycling and the catabolism of plant-derived organic compounds. Antibiotic resistance genes were consistently threefold less abundant in the desert soils than in the nondesert soils, suggesting that abiotic conditions, not competitive interactions, are more important in shaping the desert microbial communities. As the most comprehensive survey of soil taxonomic, phylogenetic, and functional diversity to date, this study demonstrates that metagenomic approaches can be used to build a predictive understanding of how microbial diversity and function vary across terrestrial biomes.

Repeated polyploidization of Gossypium genomes and the evolution of spinnable cotton fibres

Abstract: Polyploidy often confers emergent properties, such as the higher fibre productivity and quality of tetraploid cottons than diploid cottons bred for the same environments. Here we show that an abrupt five- to sixfold ploidy increase approximately 60 million years (Myr) ago, and allopolyploidy reuniting divergent Gossypium genomes approximately 1-2 Myr ago, conferred about 30-36-fold duplication of ancestral angiosperm (flowering plant) genes in elite cottons (Gossypium hirsutum and Gossypium barbadense), genetic complexity equalled only by Brassica among sequenced angiosperms. Nascent fibre evolution, before allopolyploidy, is elucidated by comparison of spinnable-fibred Gossypium herbaceum A and non-spinnable Gossypium longicalyx F genomes to one another and the outgroup D genome of non-spinnable Gossypium raimondii. The sequence of a G. hirsutum A(t)D(t) (in which 't' indicates tetraploid) cultivar reveals many non-reciprocal DNA exchanges between subgenomes that may have contributed to phenotypic innovation and/or other emergent properties such as ecological adaptation by polyploids. Most DNA-level novelty in G. hirsutum recombines alleles from the D-genome progenitor native to its New World habitat and the Old World A-genome progenitor in which spinnable fibre evolved. Coordinated expression changes in proximal groups of functionally distinct genes, including a nuclear mitochondrial DNA block, may account for clusters of cotton-fibre quantitative trait loci affecting diverse traits. Opportunities abound for dissecting emergent properties of other polyploids, particularly angiosperms, by comparison to diploid progenitors and outgroups.

Microfoundations of routines and capabilities: individuals, processes, and structure

Abstract: This article introduces the Special Issue and discusses the microfoundations of routines and capabilities, including why a microfoundations view is needed and how it may inform work on organizational and competitive heterogeneity. Building on extant research, we identify three primary categories of micro-level components underlying routines and capabilities: individuals, social processes, and structure. We discuss how these components, and their interactions, may affect routines and capabilities. In doing so, we outline a research agenda for advancing the field's understanding of the microfoundations of routines and capabilities.

Financial Literacy, Financial Education and Economic Outcomes

Abstract: In this article we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature, and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the extent to which a competitive market provides incentives for firms to educate consumers or offer products that facilitate informed choice. We review the literature on alternative policies to improve financial outcomes, and compare the evidence to evidence on the efficacy and cost of financial education. Finally, we discuss directions for future research.

Rethinking Sustained Competitive Advantage from Human Capital

Abstract: The strategy literature often emphasizes firm-specific human capital as a source of competitive advantage based on the assumption that it constrains employee mobility. We first identify three boundary conditions that limit the applicability of this logic. We then offer a more comprehensive framework of human capital–based advantage that explores both demand- and supply-side mobility constraints. The critical insight is that these mobility constraints have more explanatory power than the firm specificity of human capital.

Risk of nonaccidental and cardiovascular mortality in relation to long-term exposure to low concentrations of fine particulate matter: a Canadian national-level cohort study.

Abstract: Background: Few cohort studies have evaluated the risk of mortality associated with long-term exposure to fine particulate matter [≤ 2.5 μm in aerodynamic diameter (PM2.5)]. This is the first natio...

Improving Tests of Theories Positing Interaction

Abstract: It is well established that all interactions are symmetric: when the effect of X on Y is conditional on the value of Z, the effect of Z must be conditional on the value of X. Yet the typical practice when testing an interactive theory is to (1) view one variable, Z, as the conditioning variable, (2) offer a hypothesis about how the marginal effect of the other variable, X, is conditional on the value of Z, and (3) construct a marginal effect plot for X to test the theory. We show that the failure to make additional predictions about how the effect of Z varies with the value of X, and to evaluate them with a second marginal effect plot, means that scholars often ignore evidence that can be extremely valuable for testing their theory. As a result, they either understate or, more worryingly, overstate the support for their theories.

TEDAS: A Twitter-based Event Detection and Analysis System

Abstract: Witnessing the emergence of Twitter, we propose a Twitter-based Event Detection and Analysis System (TEDAS), which helps to (1) detect new events, to (2) analyze the spatial and temporal pattern of an event, and to (3) identify importance of events. In this demonstration, we show the overall system architecture, explain in detail the implementation of the components that crawl, classify, and rank tweets and extract location from tweets, and present some interesting results of our system.

Adoption and use of social media among public health departments

Abstract: Effective communication is a critical function within any public health system Social media has enhanced communication between individuals and organizations and has the potential to augment public health communication However, there is a lack of reported data on social media adoption within public health settings The purposes of this study were to assess: 1) the extent to which state public health departments (SHDs) are using social media; 2) which social media applications are used most often; and 3) how often social media is used interactively to engage audiences This was a non-experimental, cross sectional study of SHD social media sites Screen capture software Snag-It® was used to obtain screenshots of SHD social media sites across five applications These sites were coded for social media presence, interactivity, reach, and topic Sixty percent of SHDs reported using at least one social media application Of these, 867% had a Twitter account, 56% a Facebook account, and 43% a YouTube channel There was a statistically significant difference between average population density and use of social media (p = 01) On average, SHDs made one post per day on social media sites, and this was primarily to distribute information; there was very little interaction with audiences SHDs have few followers or friends on their social media sites The most common topics for posts and tweets related to staying healthy and diseases and conditions Limitations include the absence of a standard by which social media metrics measure presence, reach, or interactivity; SHDs were only included if they had an institutionally maintained account; and the study was cross sectional Social media use by public health agencies is in the early adoption stage However, the reach of social media is limited SHDs are using social media as a channel to distribute information rather than capitalizing on the interactivity available to create conversations and engage with the audience If public health agencies are to effectively use social media then they must develop a strategic communication plan that incorporates best practices for expanding reach and fostering interactivity and engagement

Microstructure Sensitive Design for Performance Optimization

Abstract: The accelerating rate at which new materials are appearing, and transforming the engineering world, only serves to emphasize the vast potential for novel material structure, and related performance. Microstructure-sensitive design (MSD) aims at providing inverse design methodologies that facilitate design of material internal structure for performance optimization. Spectral methods are applied across the structure, property and processing design spaces in order to compress the computational requirements for linkages between the spaces and enable inverse design. Research has focused mainly on anisotropic, polycrystalline materials, where control of local crystal orientation can result in a broad range of property combinations. This review presents the MSD framework in the context of both the engineering advances that have led to its creation, and those that complement or provide alternative methods for design of materials (meaning ‘optimization of material structure’ in this context). A variety of definitions for the structure of materials are presented, with an emphasis on correlation functions; and spectral methods are introduced for compact descriptions and efficient computations. The microstructure hull is defined as the design space for structure in the spectral framework. Reconstruction methods provide invertible links between statistical descriptions of structure, and deterministic instantiations. Subsequently, structure–property relations are reviewed, and again subjected to representation via spectral methods. The concept of a property closure is introduced as the design space for performance optimization, and methods for moving between the closures and hulls are presented as the basis for the subsequent discussion on microstructure design. Finally, the spectral framework is applied to deformation processes, and methodologies that facilitate process design are reviewed.

Investor Information Demand: Evidence from Google Searches Around Earnings Announcements: investor information demand

Abstract: The objective of this study is to investigate factors that influence investor information demand around earnings announcements and to provide insights into how variation in information demand impacts the capital market response to earnings. The Internet is one channel through which public information is disseminated to investors and we propose that one way that investors express their demand for public information is via Google searches. We find that abnormal Google search increases about two weeks prior to the earnings announcement, spikes markedly at the announcement, and continues at high levels for a period after the announcement. This finding suggests that information diffusion is not instantaneous with the release of the earnings information, but rather is spread over a period surrounding the announcement. We also find that information demand is positively associated with media attention and news, and is negatively associated with investor distraction. When investors search for more information in the days just prior to the announcement, preannouncement price and volume changes reflect more of the upcoming earnings news and there is less of a price and volume response when the news is announced. This result suggests that, when investors demand more information about a firm, the information content of the earnings announcement is partially preempted.

Diffusion Tensor Imaging in Autism Spectrum Disorder: A Review

Abstract: White matter tracts of the brain allow neurons and neuronal networks to communicate and function with high efficiency The aim of this review is to briefly introduce diffusion tensor imaging methods that examine white matter tracts and then to give an overview of the studies that have investigated white matter integrity in the brains of individuals with autism spectrum disorder (ASD) From the 48 studies we reviewed, persons with ASD tended to have decreased fractional anisotropy and increased mean diffusivity in white matter tracts spanning many regions of the brain but most consistently in regions such as the corpus callosum, cingulum, and aspects of the temporal lobe This decrease in fractional anisotropy was often accompanied by increased radial diffusivity Additionally, the review suggests possible atypical lateralization in some white matter tracts of the brain and a possible atypical developmental trajectory of white matter microstructure in persons with ASD Clinical implications and future research directions are discussed

Emerging Practice and Research in Blended Learning

Abstract: BACKGROUND AND DEFINITION OF BLENDED LEARNING Discussion of blending learning (BL) is appearing with increased frequency in both the scholarly literature and the popular press. A 2011 literature search by the author found close to 200 dissertations and hundreds of journal articles on the topic (Halverson, Graham, Spring, & Drysdale, 2012). It has also been identifi ed by the American Society for Training and Development as a top trend in the knowledge delivery industry (Rooney, 2003). Historically, blended learning was predominantly found in corporate and higher education contexts, but its use is now increasingly found in K-12 education (Picciano, Seaman, Shea, & Shaw 2012; Staker et al., 2011). Its use in higher education has grown rapidly and is predicted to become the “new traditional model” (Ross & Gage, 2006, p. 167) or the “new normal” in course delivery (Norberg, Dziuban, & Moskal, 2011, p. 207). A 2008 report sponsored by the North American Council for Online Learning (NACOL) stated, “Blended learning is likely to emerge as the predominant model of the future” (Watson, 2008, p. 3).

Use of social media in health promotion: Purposes, key performance indicators, and evaluation metrics

Abstract: Despite the expanding use of social media, little has been published about its appropriate role in health promotion, and even less has been written about evaluation. The purpose of this article is threefold: (a) outline purposes for social media in health promotion, (b) identify potential key performance indicators associated with these purposes, and (c) propose evaluation metrics for social media related to the key performance indicators. Process evaluation is presented in this article as an overarching evaluation strategy for social media.

Improving online social presence through asynchronous video

Abstract: Online learning has become a reality for many students in higher education. Unfortunately, something that has also become a reality is a sense of isolation in online courses, and Moore (1980) has warned that students' sense of distance can threaten their ability to learn. The community of inquiry framework (Garrison, Anderson, & Archer, 2000) has provided insight into ways that online interactions can improve students' and instructors' social presence and learning. Emerging video technologies may be able to improve these interactions and thus more easily support the development of communities of inquiry. In this study we interviewed students in three distinct courses using different video-based instructional strategies. A large majority of students indicated feeling that the video-based communication made their instructors seem more real, present, and familiar, and that these relationships were similar to face-to-face instruction. Video communication impacted students' social presence in similar ways, although to a lesser degree than they believed it impacted instructor social presence. We conclude with discussion for future research and practice.

An Investigation of Self-Assessment Bias in Mental Health Providers:

Abstract: Previous research has consistently found self-assessment bias (an overly positive assessment of personal performance) to be present in a wide variety of work situations. The present investigation extended this area of research with a multi-disciplinary sample of mental health professionals. Respondents were asked to: (a) compare their own overall clinical skills and performance to others in their profession, and (b) indicate the percentage of their clients who improved, remained the same, or deteriorated as a result of treatment with them. Results indicated that 25% of mental health professionals viewed their skill to be at the 90th percentile when compared to their peers, and none viewed themselves as below average. Further, when compared to the published literature, clinicians tended to overestimate their rates of client improvement and underestimate their rates of client deterioration. The implications of this self-assessment bias for improvement of psychotherapy outcomes are discussed.

A survey SCADA of and critical infrastructure incidents

Abstract: In this paper, we analyze several cyber-security incidents involving critical infrastructure and SCADA systems. We classify these incidents based on Source Sector, Method of Operations, Impact, and Target Sector. Using this standardized taxonomy we can easily compare and contrast current and future SCADA incidents.

The "Visual Depiction Effect" in Advertising: Facilitating Embodied Mental Simulation through Product Orientation

Abstract: This research demonstrates that visual product depictions within advertisements, such as the subtle manipulation of orienting a product toward a participant’s dominant hand, facilitate mental simulation that evokes motor responses. We propose that viewing an object can lead to similar behavioral consequences as interacting with the object since our minds mentally simulate the experience. Four studies show that visually depicting a product that facilitates more (vs. less) embodied mental simulation results in heightened purchase intentions. The studies support our proposed embodied mental simulation account. For instance, occupying the perceptual resources required for embodied mental simulation attenuates the impact of visual product depiction on purchase intentions. For negatively valenced products, facilitation of embodied mental simulation decreases purchase intentions.

Innate lymphoid cells responding to IL-33 mediate airway hyperreactivity independently of adaptive immunity

Abstract: Background Asthma has been considered an immunologic disease mediated by T H 2 cells and adaptive immunity. However, clinical and experimental observations suggest that additional pathways might regulate asthma, particularly in its nonallergic forms, such as asthma associated with air pollution, stress, obesity, and infection. Objectives Our goal was to understand T H 2 cell–independent conditions that might lead to airway hyperreactivity (AHR), a cardinal feature of asthma. Methods We examined a murine model of experimental asthma in which AHR was induced with glycolipid antigens, which activate natural killer T (NKT) cells. Results In this model AHR developed rapidly when mice were treated with NKT cell–activating glycolipid antigens, even in the absence of conventional CD4 + T cells. The activated NKT cells directly induced alveolar macrophages to produce IL-33, which in turn activated NKT cells, as well as natural helper cells, a newly described non-T, non-B, innate lymphoid cell type, to increase production of IL-13. Surprisingly, this glycolipid-induced AHR pathway required not only IL-13 but also IL-33 and its receptor, ST2, because it was blocked by an anti-ST2 mAb and was greatly reduced in ST2 −/− mice. When adoptively transferred into IL-13 −/− mice, both wild-type natural helper cells and NKT cells were sufficient for the development of glycolipid-induced AHR. Conclusion Because plant pollens, house dust, and some bacteria contain glycolipids that can directly activate NKT cells, these studies suggest that AHR and asthma can fully develop or be greatly enhanced through innate immune mechanisms involving IL-33, natural helper cells, and NKT cells.

Resolving the phylogeny of lizards and snakes (Squamata) with extensive sampling of genes and species

Abstract: Squamate reptiles (lizards and snakes) are one of the most diverse groups of terrestrial vertebrates. Recent molecular analyses have suggested a very different squamate phylogeny relative to morphological hypotheses, but many aspects remain uncertain from molecular data. Here, we analyse higher-level squamate phylogeny with a molecular dataset of unprecedented size, including 161 squamate species for up to 44 nuclear genes each (33 717 base pairs), using both concatenated and species-tree methods for the first time. Our results strongly resolve most squamate relationships and reveal some surprising results. In contrast to most other recent studies, we find that dibamids and gekkotans are together the sister group to all other squamates. Remarkably, we find that the distinctive scolecophidians (blind snakes) are paraphyletic with respect to other snakes, suggesting that snakes were primitively burrowers and subsequently re-invaded surface habitats. Finally, we find that some clades remain poorly supported, despite our extensive data. Our analyses show that weakly supported clades are associated with relatively short branches for which individual genes often show conflicting relationships. These latter results have important implications for all studies that attempt to resolve phylogenies with large-scale phylogenomic datasets.