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Level Analysis (level + analysis)
Selected AbstractsImpacts of Alternative Manure Application Rates on Texas Animal Feeding Operations: A Macro Level Analysis,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2008E. Osei Abstract:, An integrated economic and environmental modeling system was developed for evaluating agro-environmental policies and practices implemented on large scales. The modeling system, the Comprehensive Economic and Environmental Optimization Tool-Macro Modeling System (CEEOT-MMS), integrates the Farm-level Economic Model (FEM) and the Agricultural Policy Environmental eXtender (APEX) model, as well as national databases and clustering and aggregation algorithms. Using micro simulations of statistically derived representative farms and subsequent aggregation of farm-level results, a wide range of agricultural best management practices can be investigated within CEEOT-MMS. In the present study, CEEOT-MMS was used to evaluate the economic and water quality impacts of nitrogen (N) and phosphorus (P) based manure application rates when implemented on all animal feeding operations in the State of Texas. Results of the study indicate that edge-of-field total P losses can be reduced by about 0.8 kg/ha/year or 14% when manure applications are calibrated to supply all of the recommended crop P requirements from manure total P sources only, when compared to manure applications at the recommended crop N agronomic rate. Corresponding economic impacts are projected to average a US$4,800 annual cost increase per farm. Results are also presented by ecological subregion, farm type, and farm size categories. [source] Multiple-Cell Spike Density and Neural Noise Level Analysis by Semimicroelectrode Recording for Identification of the Subthalamic Nucleus During Surgery for Parkinson's DiseaseNEUROMODULATION, Issue 1 2008Toshikazu Kano MD ABSTRACT Objective.,, For targeting the subthalamic nucleus (STN), we attempted to quantify the changes in multiple cell activities by computing the neural noise level and multiple-cell spike density (MSD). Methods.,, We analyzed the neural noise level and MSD by stepwise recording at every 0.25-mm increment during the final tracking in 90 sides of 45 patients with Parkinson's disease. The MSD was analyzed with cut-off levels ranging from 1.2- to 2.0-fold the neural noise level in the internal capsule or zona incerta in each trajectory. Results.,, The dorsal boundary of the STN was identified from an increase in the neural noise ratio in all sides. The ventral boundary was identifiable, however, from a decrease in the neural noise ratio in only 70 sides (78%). In contrast, both the dorsal and ventral boundaries were clearly identified from an increase and a decrease in the MSD, respectively, in all of the 90 sides. Conclusion.,, MSD analysis by semimicroelectrode recording represents a useful, practical, and apparently reliable means for identifying the boundaries of the STN. [source] Gene, region and pathway level analyses in whole-genome studiesGENETIC EPIDEMIOLOGY, Issue 3 2010Omar De la Cruz Abstract In the setting of genome-wide association studies, we propose a method for assigning a measure of significance to pre-defined sets of markers in the genome. The sets can be genes, conserved regions, or groups of genes such as pathways. Using the proposed methods and algorithms, evidence for association between a particular functional unit and a disease status can be obtained not just by the presence of a strong signal from a SNP within it, but also by the combination of several simultaneous weaker signals that are not strongly correlated. This approach has several advantages. First, moderately strong signals from different SNPs are combined to obtain a much stronger signal for the set, therefore increasing power. Second, in combination with methods that provide information on untyped markers, it leads to results that can be readily combined across studies and platforms that might use different SNPs. Third, the results are easy to interpret, since they refer to functional sets of markers that are likely to behave as a unit in their phenotypic effect. Finally, the availability of gene-level P -values for association is the first step in developing methods that integrate information from pathways and networks with genome-wide association data, and these can lead to a better understanding of the complex traits genetic architecture. The power of the approach is investigated in simulated and real datasets. Novel Crohn's disease associations are found using the WTCCC data. Genet. Epidemiol. 34: 222,231, 2010. © 2009 Wiley-Liss, Inc. [source] The Advantages of Multilevel ApproachesJOURNAL OF SOCIAL ISSUES, Issue 3 2006Thomas F. Pettigrew Editors' introduction: Thomas F. Pettigrew was born and raised in tightlysegregated Richmond, Virginia in 1931. But his Scottish-immigrant family did not subscribe to the South's racist norms, and he identified with and had early positive contact with African Americans. As an undergraduate at the University of Virginia, he discovered that there was a discipline that studied and resisted racism. These formative experiences forged his career path in social psychology to study intergroup relations. As a student of Allport's, Pettigrew is widely recognized as having expanded personality-oriented perspectives on prejudice to include a more social, contextualized orientation (Kimmel, 1986). In that same vein, he focuses his commentary on incorporating multiple levels of analysis as we integrate theory, research and practice on intergroup relations. He emphasizes the importance of macro-level,institutional and societal,contextualization of social psychological work. Pettigrew thoughtfully considers each article in the issue and contends that multiple level analyses, and incorporating the macro-level, are critical for theoretical and empirical progress as well as maximizing effectiveness of interventions. [source] Renal Allografts with IF/TA Display Distinct Expression Profiles of Metzincins and Related GenesAMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2009S. Rödder Chronic renal allograft injury is often reflected by interstitial fibrosis (IF) and tubular atrophy (TA) without evidence of specific etiology. In most instances, IF/TA remains an irreversible disorder, representing a major cause of long-term allograft loss. As members of the protease family metzincins and functionally related genes are involved in fibrotic and sclerotic processes of the extracellular matrix (ECM), we hypothesized their deregulation in IF/TA. Gene expression and protein level analyses using allograft biopsies with and without Banff'05 classified IF/TA illustrated their deregulation. Expression profiles of these genes differentiated IF/TA from Banff'05 classified Normal biopsies in three independent microarray studies and demonstrated histological progression of IF/TA I to III. Significant upregulation of matrix metalloprotease-7 (MMP-7) and thrombospondin-2 (THBS-2) in IF/TA biopsies and sera was revealed in two independent patient sets. Furthermore, elevated THBS-2, osteopontin (SPP1) and ,-catenin may play regulatory roles on MMP. Our findings further suggest that deregulated ECM remodeling and possibly epithelial to mesenchymal transition (EMT) are implicated in IF/TA of kidney transplants, and that metzincins and related genes play an important role in these processes. Profiling of these genes may be used to complement IF/TA diagnosis and to disclose IF/TA progression in kidney transplant recipients. [source] Relating individual differences in Attitude toward Ambiguity to risky choicesJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 2 2001Marco Lauriola Abstract Subjects (76 adult Italians of varying ages) completed a two-part procedure. One part used an Ellsberg-type task which allowed for both aggregate and individual level analysis of Attitude toward Ambiguity. The other part used an expanded risky choice task to assess the same subjects' Attitude toward Risk. While there was an overall tendency for subjects to be slightly ambiguity-averse, there was a positive correlation between Attitude toward Ambiguity and Attitude toward Risk. This relation was particularly strong when the risky choice was to avoid a loss rather than to achieve a gain. Copyright © 2001 John Wiley & Sons, Ltd. [source] Therapist effects in randomised controlled trials: what to do about themJOURNAL OF CLINICAL NURSING, Issue 7-8 2010Stephen J Walters Aims and objectives., The aim of this study is to describe and compare three statistical methods to allow for therapist effects in individually randomised controlled trials. Background., In an individually randomised controlled trial where the intervention is delivered by a health professional it seems likely that the effectiveness of the intervention, independent of any treatment effect, could depend on the skill of the health professional delivering it. This leads to a potential clustering of the outcomes for the patients being treated by the same health professional. Design., Retrospective statistical analysis of outcomes from four example randomised controlled trial datasets with potential clustering by health professional. Methods., Three methods to allow for clustering are described: cluster level analysis; random effects models and marginal models. These models were fitted to continuous outcome data from four example randomised controlled trial datasets with potential clustering by health professional. Results., The cluster level models produced the widest confidence intervals. Little difference was found between the estimates of the regression coefficients for the treatment effect and confidence intervals between the individual patient level models for the datasets. The conclusions reached for each dataset match those published in the original papers. The intracluster correlation coefficient ranged from <0·001,0·04 for the outcomes, which shows only minor levels of clustering within the datasets. Conclusions., The models, which use individual level data are to be preferred. Treatment coefficients from these models have different interpretations. The choice of model should depend on the scientific question being asked. Relevance to clinical practice., We recommend that researchers should be aware of any potential clustering, by health professional, in their randomised controlled trial and use appropriate methods to account for this clustering in the statistical analysis of the data. [source] A firm level analysis of trade, technology and employment in South AfricaJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 1 2004Lawrence Edwards This paper uses two firm level surveys, the National Enterprise (NE) survey and the Greater Johannesburg Metropolitan Area (GJMA) survey, to explore the implications of globalization for employment in South Africa. These relationships are explored using cross-tabulations and estimated labour demand functions. The paper finds that rising import penetration negatively affected employment in large firms, but not small firms. Relatively large declines in employment also occurred within export firms, despite improvements in export competitiveness and export growth through trade liberalization. Finally, the study finds that skill-biased and trade-induced technological change, as reflected in increased use of computers, foreign investment and the importation of raw material inputs, have raised the skill intensity of production. Copyright © 2004 John Wiley & Sons, Ltd. [source] Document classification techniques for automated technology readiness level analysisJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 4 2008Barry L. Britt The overhead of assessing technology readiness for deployment and investment purposes can be costly to both large and small businesses. Recent advances in the automatic interpretation of technology readiness levels (TRLs) of a given technology can substantially reduce the risk and associated cost of bringing these new technologies to market. Using vector-space information-retrieval models, such as latent semantic indexing, it is feasible to group similar technology descriptions by exploiting the latent structure of term usage within textual documents. Once the documents have been semantically clustered (or grouped), they can be classified based on the TRL scores of (known) nearest-neighbor documents. Three automated (no human curation) strategies for assigning TRLs to documents are discussed with accuracies as high as 86% achieved for two-class problems. [source] A parallel analysis of individual and ecological data on residential radon and lung cancer in south-west EnglandJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 1 2001Sarah Darby Parallel individual and ecological analyses of data on residential radon have been performed using information on cases of lung cancer and population controls from a recent study in south-west England. For the individual analysis the overall results indicated that the relative risk of lung cancer at 100 Bq m,3 compared with at 0 Bq m,3 was 1.12 (95% confidence interval (0.99, 1.27)) after adjusting for age, sex, smoking, county of residence and social class. In the ecological analysis substantial bias in the estimated effect of radon was present for one of the two counties involved unless an additional variable, urban,rural status, was included in the model, although this variable was not an important confounder in the individual level analysis. Most of the methods that have been recommended for overcoming the limitations of ecological studies would not in practice have proved useful in identifying this variable as an appreciable source of bias. [source] Extending the task,artifact framework with organizational learningKNOWLEDGE AND PROCESS MANAGEMENT: THE JOURNAL OF CORPORATE TRANSFORMATION, Issue 1 2010Jiang Hao Over the past decade there has been an increased focus on the importance of contextual factors in all IT disciplines. At the same time, scholars have heeded the call for investigating the creation of more effective synergies between science and design. For example, the task,artifact (TA) framework was developed to support better utilization of behavioral, cognitive, and social science in Human,Computer Interaction (HCI) design. This framework is based on the general developmental pattern of human activities and technologiesteamed with two analytical tools for design. In this paper, we extend this framework from its original focus on individual and small group HCI to the organizational level utilizing organizational learning theory. This extension will (1) integrate relevant concepts and analysis drawn from the social sciences in order to guide design more effectively; (2) incorporate organizational level analysis, when we study information artifact design and appropriation; and (3) help organizations complete their learning circle. Copyright © 2010 John Wiley & Sons, Ltd. [source] A network analysis of the single nucleotide polymorphisms in acute allergic diseasesALLERGY, Issue 1 2010J. Renkonen Abstract Background:, Genetics of acute allergies has focused on identifying single nucleotide polymorphisms (SNPs) within genes relevant in the pathogenesis. In this study, we begin a systems biology analysis of the interconnectivity and biological functions of these genes, their transcripts and their corresponding proteins. Methods:, The literature (Pubmed) was searched for SNPs within genes relevant in acute allergic diseases. The SNP-modified genes were converted to corresponding proteins and their protein,protein interactions were searched from six different databases. This interaction network was analysed with annotated vocabularies (ontologies), such as Gene Ontology, Reactome and Nature pathway interaction database. Time-series transcriptomics was performed with nasal epithelial cells obtained from allergic patients and their healthy control subjects. Results:, A total of 39 genes with SNPs related to acute allergic diseases were found from a literature search. The corresponding proteins were then hooked into a large protein,protein interaction network with the help of various databases. Twenty-five SNP-related proteins had more than one interacting protein and a network contained 95 proteins, and 182 connections could be generated. This network was 10-fold enriched with protein kinases and proteins involved in the host,virus interaction compared with background human proteome. Finally, eight of the 95 nodes on our network displayed nasal epithelial transcriptomal regulation in a time-series analysis collected from birch allergic patients during the spring pollen season. Conclusions:, Signal transduction with special reference to host,virus interactions dominated in the allergy-related protein interaction network. Systems level analysis of allergy-related mutation can provide new insights into pathogenetic mechanisms of the diseases. [source] Genetic diversity enhanced by ancient introgression and secondary contact in East Pacific black mangrovesMOLECULAR ECOLOGY, Issue 11 2008ALEJANDRO NETTEL Abstract Regional distribution of genetic diversity in widespread species may be influenced by hybridization with locally restricted, closely related species. Previous studies have shown that Central American East Pacific populations of the wide-ranged Avicennia germinans, the black mangrove, harbour higher genetic diversity than the rest of its range. Genetic diversity in this region might be enhanced by introgression with the locally restricted Avicennia bicolor. We tested the hypotheses of ancient hybridization using phylogenetic analysis of the internal transcribed spacer region (ITS) of the nuclear ribosomal DNA and intergenic chloroplast DNA; we also tested for current hybridization by population level analysis of nuclear microsatellites. Our results unveiled ancient ITS introgression between a northern Pacific Central American A. germinans lineage and A. bicolor. However, microsatellite data revealed contemporary isolation between the two species. Polymorphic ITS sequences from Costa Rica and Panama are consistent with a zone of admixture between the introgressant ITS A. germinans lineage and a southern Central American lineage of A. germinans. Interspecific introgression influenced lineage diversity and divergence at the nuclear ribosomal DNA; intraspecific population differentiation and secondary contact are more likely to have enhanced regional genetic diversity in Pacific Central American populations of the widespread A. germinans. [source] Comparative analysis of gene expression on mRNA and protein level during development of Streptomyces cultures by using singular value decompositionPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 21 2007Jiri Vohradsky Dr. Abstract This paper describes a comparative systems level analysis of the developmental proteome and transcriptome in the model antibiotic-producing eubacterium Streptomyces coelicolor, cultured on different media. The analysis formulates expression as the superposition of effects of regulatory networks and biological processes which can be identified using singular value decomposition (SVD) of a data matrix formed by time series measurements of expression of individual genes throughout the cell cycle of the bacterium. SVD produces linearly orthogonal factors, each of which can represent an independent system behavior defined by a linear combination of the genes/proteins highly correlated with the corresponding factor. By using SVD of the developmental time series of gene expression, as measured by both protein and RNA levels, we show that on the highest level of control (representing the basic kinetic behavior of the population), the results are identical, regardless of the type of experiment or cultivation method. The results show that this approach is capable of identifying basic regulatory processes independent of the environment in which the organism lives. It also shows that these processes are manifested equally on protein and RNA levels. Biological interpretation of the correlation of the genes and proteins with significant eigenprofiles (representing the highest level kinetic behavior of protein and/or RNA synthesis) revealed their association with metabolic processes, stress responses, starvation, and secondary metabolite production. [source] Local dynamic partial least squares approaches for the modelling of batch processesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2008N. M. Fletcher Abstract The application of multivariate statistical projection based techniques has been recognized as one approach to contributing to an increased understanding of process behaviour. The key methodologies have included multi-way principal component analysis (PCA), multi-way partial least squares (PLS) and batch observation level analysis. Batch processes typically exhibit nonlinear, time variant behaviour and these characteristics challenge the aforementioned techniques. To address these challenges, dynamic PLS has been proposed to capture the process dynamics. Likewise approaches to removing the process nonlinearities have included the removal of the mean trajectory and the application of nonlinear PLS. An alternative approach is described whereby the batch trajectories are sub-divided into operating regions with a linear/linear dynamic model being fitted to each region. These individual models are spliced together to provide an overall nonlinear global model. Such a structure provides the potential for an alternative approach to batch process performance monitoring. In the paper a number of techniques are considered for developing the local model, including multi-way PLS and dynamic multi-way PLS. Utilising the most promising set of results from a simulation study of a batch process, the local model comprising individual linear dynamic PLS models was benchmarked against global nonlinear dynamic PLS using data from an industrial batch fermentation process. In conclusion the results for the local operating region techniques were comparable to the global model in terms of the residual sum of squares but for the global model structure was evident in the residuals. Consequently, the local modelling approach is statistically more robust. L'application de techniques basées sur la projection statistique multivariée est reconnue comme étant une approche qui contribue à une meilleure compréhension du comportement des procédés. Les méthodologies clés incluent l'analyse des composantes principales (PCA) à plusieurs critères de classification, les moindres carrés partiels (PLS) à plusieurs critères de classification et l'analyse des niveaux d'observation discontinus. Les procédés discontinus présentent typiquement un comportement non linéaire et variable dans le temps et ces caractéristiques mettent au défi les techniques mentionnées ci-dessus. Devant ces défis, la méthode PLS dynamique est proposée pour saisir la dynamique des procédés. Des approches semblables pour supprimer la non linéarité des procédés incluent le retrait de la trajectoire principale et l'application des PLS non linéaires. On décrit une autre approche où les trajectoires discontinues sont subdivisées en régions opératoires avec un modèle dynamique linéaire/linéaire adapté à chaque région. Ces modèles individuels sont raccordés pour obtenir un modèle non linéaire global. Une telle structure présente un potentiel pour une approche différente du suivi des performances des procédés discontinus. Dans cet article, plusieurs techniques sont considérées pour la mise au point du modèle local, incluant les PLS à plusieurs critères de classification et les PLS à plusieurs critères de classification dynamique. En utilisant la série de résultats les plus prometteurs d'une étude de simulation d'un procédé discontinu, le modèle local comprenant les modèles de PLS dynamiques linéaires individuels a été comparé à la méthode de PLS non linéaires dynamique globale utilisant des données d'un procédé de fermentation discontinu industriel. En conclusion, les résultats pour les techniques des régions opératoires locales sont comparables au modèle global en termes de somme des carrés des résidus mais pour le modèle global, la présence d'une structure dans les résidus est évidente. En conséquence, l'approche de modélisation locale est statistiquement plus robuste. 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