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Reduced Set (reduced + set)
Selected AbstractsRefining and validating the Social Interaction Anxiety Scale and the Social Phobia ScaleDEPRESSION AND ANXIETY, Issue 2 2009R. Nicholas Carleton M.A. Abstract Background: The Social Interaction Anxiety Scale and Social Phobia Scale6 are companion measures for assessing symptoms of social anxiety and social phobia. The scales have good reliability and validity across several samples,3, 6 however, exploratory and confirmatory factor analyses have yielded solutions comprising substantially different item content and factor structures. These discrepancies are likely the result of analyzing items from each scale separately or simultaneously. The current investigation sets out to assess items from those scales, both simultaneously and separately, using exploratory and confirmatory factor analyses in an effort to resolve the factor structure. Methods: Participants consisted of a clinical sample (n5353; 54% women) and an undergraduate sample (n5317; 75% women) who completed the Social Interaction Anxiety Scale and Social Phobia Scale, along with additional fear-related measures to assess convergent and discriminant validity. Results: A three-factor solution with a reduced set of items was found to be most stable, irrespective of whether the items from each scale are assessed together or separately. Items from the Social Interaction Anxiety Scale represented one factor, whereas items from the Social Phobia Scale represented two other factors. Conclusion: Initial support for scale and factor validity, along with implications and recommendations for future research, is provided. Depression and Anxiety, 2009. © 2009 Wiley-Liss, Inc. [source] Quantified superiority of cognitive behaviour therapy to antidepressant drugs: a challenge to an earlier meta-analysisACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2008G. B. Parker Objective:, The study aimed to review the conclusion of a previously published meta-analysis which quantified distinct superiority of cognitive therapy to antidepressant drug-therapy (P < 0.0001). Method:, We sought to include all studies used in the original meta-analysis. Adopting both that study's inclusion criteria and additional criteria resulted in a reduced set of studies. We analysed both ,completer' and ,intention to treat' data, using effect size and odds ratio quantification. Results:, There was an overall trend for cognitive therapy to be superior to antidepressant drug-therapy, but this was significant for only one of the four meta-analyses (an intention to treat analysis). We demonstrated considerable heterogeneity between studies, and a significantly higher drop-out rate in the antidepressant groups. Conclusion:, The previous interpretation , cognitive therapy being distinctly superior to antidepressant medication , cannot be sustained from the currently analysed data set. [source] Bent and Linear Forms of the (,-Oxo)bis[trichloroferrate(III)] Dianion: An Intermolecular Effect , Structural, Electronic and Magnetic PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2003Agustí Lledós Abstract We have analyzed the great diversity of Fe,O,Fe angles, 140,180°, found in the X-ray structures of the (,-oxo)bis[trichloroferrate(III)] dianion [Cl3FeOFeCl3]2, from both experimental and theoretical points of view. Theoretical calculations show that only the linear isomer is found as a minimum on the potential energy surface. Detailed analysis of the crystal packing indicates that the angular form is due to attractive intermolecular interactions. Analysis of a selected reduced set of the 45 crystal structures retrieved from the Cambridge Structural Database allowed us to classify the bending of the [Cl3FeOFeCl3]2, dianion in three categories, depending on the balance and strength of the intermolecular O···H,X contacts. A crystal diffraction study on the bis(benzyltrimethylammonium) salt has shown both bent (144.6°) and linear (180°) forms of the (,-oxo)bis[trichloroferrate(III)] dianion. The magnetic susceptibility of this compound has been fitted by assuming two equally weighted contributions (Jang and Jlin) of the two forms, considering Jang , Jlin estimated by theoretical calculations. The obtained Jang and Jlin of ,117 and ,133 cm,1 respectively, agree well with B3LYP results. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Phylogenetic distribution of microRNAs supports the basal position of acoel flatworms and the polyphyly of PlatyhelminthesEVOLUTION AND DEVELOPMENT, Issue 5 2007Lorenzo F. Sempere SUMMARY Phylogenetic analyses based on gene sequences suggest that acoel flatworms are not members of the phylum Platyhelminthes, but instead are the most basal branch of triploblastic bilaterians. Nonetheless, this result has been called into question. An alternative test is to use qualitative molecular markers that should, in principle, exclude the possibility of convergent (homoplastic) evolution in unrelated groups. microRNAs (miRNAs), noncoding regulatory RNA molecules that are under intense stabilizing selection, are a newly discovered set of phylogenetic markers that can resolve such taxonomic disputes. The acoel Childia sp. has recently been shown to possess a subset of the conserved core of miRNAs found across deuterostomes and protostomes, whereas a polyclad flatworm,in addition to this core subset,possesses miRNAs restricted to just protostomes. Here, we examine another acoel, Symsagittifera roscoffensis, and three other platyhelminths. Our results show that the distribution of miRNAs in S. roscoffensis parallels that of Childia. In addition, two of 13 new miRNAs cloned from a triclad flatworm are also found in other lophotrochozoan protostomes, but not in ecdysozoans, deuterostomes, or in basal metazoans including acoels. The limited set of miRNAs found in acoels, intermediate between the even more reduced set in cnidarians and the larger and expanding set in the rest of bilaterians, is compelling evidence for the basal position of acoel flatworms and the polyphyly of Platyhelminthes. [source] Improved process monitoring using nonlinear principal component models,INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 5 2008David Antory This paper presents two new approaches for use in complete process monitoring. The first concerns the identification of nonlinear principal component models. This involves the application of linear principal component analysis (PCA), prior to the identification of a modified autoassociative neural network (AAN) as the required nonlinear PCA (NLPCA) model. The benefits are that (i) the number of the reduced set of linear principal components (PCs) is smaller than the number of recorded process variables, and (ii) the set of PCs is better conditioned as redundant information is removed. The result is a new set of input data for a modified neural representation, referred to as a T2T network. The T2T NLPCA model is then used for complete process monitoring, involving fault detection, identification and isolation. The second approach introduces a new variable reconstruction algorithm, developed from the T2T NLPCA model. Variable reconstruction can enhance the findings of the contribution charts still widely used in industry by reconstructing the outputs from faulty sensors to produce more accurate fault isolation. These ideas are illustrated using recorded industrial data relating to developing cracks in an industrial glass melter process. A comparison of linear and nonlinear models, together with the combined use of contribution charts and variable reconstruction, is presented. © 2008 Wiley Periodicals, Inc. [source] Selecting Predictor Subsets: Considering validity and adverse impactINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 3 2010Wilfried De Corte The paper proposes a procedure for designing Pareto-optimal selection systems considering validity, adverse impact and constraints on the number of predictors from a larger subset that can be included in an operational selection system. The procedure determines Pareto-optimal composites of a given maximum size thereby solving the dual task of identifying the predictors that will be included in the reduced set and determining the weights with which the retained predictors will be combined to the composite predictor. Compared with earlier proposals, the simultaneous consideration of both tasks makes it possible to combine several strategies for reducing adverse impact in a single procedure. In particular, the present approach allows integrating (a) investigating a large number of possible predictors (such as multitest battery of ability tests, or a collection of ability and nonability measures); (b) explicit predictor weighting within feasible test procedures of a given limited size. [source] Impact of Age at First Drink on Stress-Reactive DrinkingALCOHOLISM, Issue 1 2007Deborah A. Dawson Background: Although recent data from animal models indicate that adolescent ethanol exposure increases self-administered ethanol intake in adult rats, the impact of age at first drink on the association between stress and drinking has not been studied in humans. Methods: Data collected in the 2001 to 2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were used to estimate the extent to which age at first drink modified the association between stress and average daily volume (ADV) of ethanol intake in a sample of 26,946 past-year drinkers. Successive models estimated the magnitude and significance of the interaction between age at first drink (ages 14 or younger, 15,17, and 18 or older) and number of stressors (out of 12 past-year negative life events) after (1) adjusting for sociodemographic characteristics, (2) additionally adjusting for family history of alcoholism, comorbid psychopathology, adolescent, and past-year tobacco and illicit drug use, and (3) additionally adjusting for all other significant interactions with number of stressors. Results: Even after adjusting for a wide range of confounders and their interactions with stress, initiation of drinking at ages 14 and younger increased the association between the number of stressors and ADV of ethanol consumption by 8% (p=0.014), when considering the full range of 12 potential stressors. In fact, the positive association between stress and consumption was significant only for this group of drinkers with early adolescent exposure to ethanol. Within this group, ADV of consumption increased by an average of 7% with each additional stressor experienced, although the exact percentage increase varied as a function of other covariates that had significant interactions with stress. When a reduced set of 4 stressors was considered, the magnitudes of the associations were mostly unchanged, but the modifying effect of age at first drink fell short of statistical significance (p=0.309) in the fully adjusted model. Conclusions: The findings of this study are consistent with the argument that early-onset drinking may increase stress-reactive ethanol consumption; however, these findings need to be replicated in an experimental human study in order to control fully the direction of the relationship between stress and consumption. [source] Web server suite for complex mixture analysis by covariance NMRMAGNETIC RESONANCE IN CHEMISTRY, Issue S1 2009Fengli Zhang Abstract Elucidation of the chemical composition of biological samples is a main focus of systems biology and metabolomics. Their comprehensive study requires reliable, efficient, and automatable methods to identify and quantify the underlying metabolites. Because nuclear magnetic resonance (NMR) spectroscopy is a rich source of molecular information, it has a unique potential for this task. Here we present a suite of public web servers (http://spinportal.magnet.fsu.edu), termed COLMAR, which facilitates complex mixture analysis by NMR. The COLMAR web portal presently consists of three servers: COLMAR covariance calculates the covariance NMR spectrum from an NMR input dataset, such as a TOCSY spectrum; COLMAR DemixC method decomposes the 2D covariance TOCSY spectrum into a reduced set of nonredundant 1D cross sections or traces, which belong to individual mixture components; and COLMAR query screens the traces against a NMR spectral database to identify individual compounds. Examples are presented that illustrate the utility of this web server suite for complex mixture analysis. Copyright © 2009 John Wiley & Sons, Ltd. [source] Selection of Descriptors for Particle Shape CharacterizationPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 1 2003Abstract Conventional shape descriptors, formed from a ratio of two particle size measurements, are among the simplest of the many methods used for quantitative particle shape characterization. However, a significant limitation of using one of these shape descriptors is that its value is often not unique to a specific shape. Use of several different shape descriptors may circumvent this problem but, as particle size can be defined in a large number of ways, a similarly large number of shape descriptors can be defined. While some differ substantially, others are only subtly different, conveying similar information. Thus, it is not obvious which of the many possible descriptors should be utilized. In this paper, two-dimensional particle shape descriptors obtained by image analysis of six different commercially sourced powders were considered. Techniques of cluster and correlation analysis were applied to assist in identifying redundant descriptors for shape characterization of these powder particles, allowing for efficient description of shape using a reduced set. It was found that at least two descriptors are required: aspect ratio and the square root of form factor. Significantly, each descriptor is most sensitive to a different attribute of shape: elongation and ruggedness, respectively. [source] From Shallow to Deep: Toward a Thorough Cultural Analysis of School Achievement PatternsANTHROPOLOGY & EDUCATION QUARTERLY, Issue 4 2008Mica Pollock What do anthropologists of education do? Many observers think that we provide quick glosses on what various "cultures",typically racialized, ethnic, and national-origin groups,"do" in schools. Hervé Varenne and I each name an alternative form of analysis that we think should be central to the subfield. Varenne argues that anthropologists of education should expand analysis of teaching and learning beyond (American) schools and classrooms and examine everyday life in various places as containing countless moments of teaching and learning that are worth understanding. Varenne reminds us that teaching and learning occur nonstop in everyday life, not just in classrooms. "Education" is about far more than what we typically call "achievement," which usually translates into grades, graduation, or test scores.1 This long-standing way of thinking anthropologically about "education" is essential to exploding simplistic notions of what, when, how, and from whom people "learn." In my essay, I contend that U.S. anthropologists of education also need to analyze thoroughly how U.S. school achievement patterns take shape in real time. I argue that it is our particular responsibility to counteract "shallow" analyses of "culture" in schools, which purport to explain "achievement gaps" by making quick claims about how parents and children from various racial, ethnic, national-origin, or class groups react to schools. Such shallow analyses dangerously oversimplify the social processes, interactions, and practices that create disparate outcomes for children. Shallow cultural analyses are common in both journalism and popular discourse,and in schools of education as well (see Ladson-Billings 2006 for a related critique). They are explanatory claims that name a group as having a "cultural" set of behaviors and then name that "cultural" behavior as the cause of the group's school achievement outcomes. (E.g., some argue that "group x"[e.g., "Asians"] employs a "group x behavior"[e.g., "push their children"] that causes "high" or "low" achievement.) Such claims allow people to explain achievement outcomes too simply as the production of parents and children without ever actually examining the real-life experiences of specific parents and children in specific opportunity contexts. Going deeper requires pressing for actual, accurate information about the everyday interactions among real-life parents, children, and other actors that add up to school achievement patterns (graduation rates, dropout rates, skill-test scores, suspension lists, and the like). When anthropologists of education say that we study culture, we mean that we are studying the organization of people's everyday interactions in concrete contexts. Shallow analyses of "culture" that purport to describe only how a "group's" parents train its children blame a reduced set of actors, behaviors, and processes for educational outcomes, and they include a reduced set of actors and actions in a reduced set of projects for educational improvement. Anthropologists of education should make clear that we examine children's experiences both in context and in appropriate detail; we study interactional processes that other observers might describe too quickly or with insufficient information.2 I think that if anthropologists of education explicitly, publicly, and colloquially name what counts as deep, thorough cultural analysis of American school achievement patterns, we will make ourselves far better prepared to respond to harmfully shallow claims made by journalists, colleagues, and educators alike. We will also support other stakeholders in children's lives (including teachers and teacher educators) to think more thoroughly about which actions, by whom, and in what situations produce children's achievement. This short essay suggests four key ways that anthropologists of education can, do, and should get "deep" in analyzing American achievement patterns. I invite colleagues to edit and extend this list in future editions of AEQ. [source] Reduction of a set of elementary modes using yield analysisBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009Hyun-Seob Song Abstract This article proposes a new concept termed "yield analysis" (YA) as a method of extracting a subset of elementary modes (EMs) essential for describing metabolic behaviors. YA can be defined as the analysis of metabolic pathways in yield space where the solution space is a bounded convex hull. Two important issues arising in the analysis and modeling of a metabolic network are handled. First, from a practical sense, the minimal generating set spanning the yield space is recalculated. This refined generating set excludes all the trivial modes with negligible contribution to convex hull in yield space. Second, we revisit the problem of decomposing the measured fluxes among the EMs. A consistent way of choosing the unique, minimal active modes among a number of possible candidates is discussed and compared with two other existing methods, that is, those of Schwartz and Kanehisa (Schwartz and Kanehisa, 2005. Bioinformatics 21: 204,205) and of Provost et al. (Provost et al., 2007. Proceedings of the 10th IFAC Symposium on Computer Application in Biotechnology, 321,326). The proposed idea is tested in a case study of a metabolic network of recombinant yeasts fermenting both glucose and xylose. Due to the nature of the network with multiple substrates, the flux space is split into three independent yield spaces to each of which the two-staged reduction procedure is applied. Through a priori reduction without any experimental input, the 369 EMs in total was reduced to 35 modes, which correspond to about 91% reduction. Then, three and four modes were finally chosen among the reduced set as the smallest active sets for the cases with a single substrate of glucose and xylose, respectively. It should be noted that the refined minimal generating set obtained from a priori reduction still provides a practically complete description of all possible states in the subspace of yields, while the active set covers only a specific set of experimental data. Biotechnol. Bioeng. 2009;102: 554,568. © 2008 Wiley Periodicals, Inc. [source] | ||||||||||||||||