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Underlying Structure (underlying + structure)
Selected AbstractsEuropean Schoolnet: enabling school networkingEUROPEAN JOURNAL OF EDUCATION, Issue 4 2009SANTI SCIMECA School networking is increasingly important in a globalised world, where schools themselves can be actors on an international stage. This article builds on the activities and experience of the longest established European initiative in this area, European Schoolnet (EUN), a network of 31 Ministries of Education. First, we offer an introduction covering school networks. We then describe the case of European Schoolnet, its history, role, and relationship with other school networks in the world. We then describe the underlying structure of EUN school networks and their basic characteristics. Using these basic characteristics as a framework, we consider a number of eTwinning, European Schoolnet networks: Network of Innovative Schools (ENIS) and myEUROPE. Last, we identify key features of network literacy, potential future trends in school networks, and areas where further research is needed in this field, and offer some recommendations. [source] A universal metric for sequential MIMO detection,EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 8 2007Christian Kuhn Conventionally, detection in multiple-antenna systems is based on a tree-search or a lattice-search with a metric that can be computed by recursively accumulating the corresponding metric increments for a given hypothesis. For that purpose, a multiple-antenna detector traditionally applies a preprocessing to obtain the search-metric in a suitable form. In contrast to that, we present a reformulation of the search-metric that directly allows for an appropriate evaluation of the metric on the underlying structure without the need for a computationally costly preprocessing step. Unlike the traditional approach, the new metric can also be applied when the system has fewer receive than transmit antennas. We present simulation results in which the new metric is applied for turbo detection involving the list-sequential (LISS) detector that was pioneered by Joachim Hagenauer. Copyright © 2007 John Wiley & Sons, Ltd. [source] Assessing the antecedents of transfer intentions in a training contextINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2004M. Anthony Machin This study examined the underlying structure of transfer climate and those aspects of transfer climate that were related to pre-training self-efficacy, pre-training motivation, and post-training transfer implementation intentions. Positive and negative affectivity (PA and NA) were also measured in order to better understand the relationship of these variables to trainees' perceptions of the transfer climate and the other training-related variables. Transfer climate was best represented by two underlying constructs, although these were correlated. After controlling for PA and NA, none of the transfer climate variables were significantly related to pre-training self-efficacy, while only positive reinforcement was significantly related to pre-training motivation. Pre-training self-efficacy was also a significant predictor of pre-training motivation, even after controlling for PA and NA. Negative affectivity was the only significant predictor of post-training transfer implementation intentions. Further research needs to clarify whether PA and NA are contributors to the trainees' perceptions of the transfer climate or are a product of these perceptions. [source] Long-term changes in the trophic level of the Celtic Sea fish community and fish market price distributionJOURNAL OF APPLIED ECOLOGY, Issue 3 2002J. K. Pinnegar Summary 1The intensive exploitation of fish communities often leads to substantial reductions in the abundance of target species, with ramifications for the structure and stability of the ecosystem as a whole. 2We explored changes in the mean trophic level of the Celtic Sea (ICES divisions VII f,j) fish community using commercial landings, survey data and estimates of trophic level derived from the analysis of nitrogen stable isotopes. 3Our analyses showed that there has been a significant decline in the mean trophic level of survey catches from 1982 to 2000 and a decline in the trophic level of landings from 1946 to 1998. 4The decline in mean trophic level through time resulted from a reduction in the abundance of large piscivorous fishes and an increase in smaller pelagic species which feed at a lower trophic level. 5Similar patterns of decline in the trophic level of both catches and landings imply that there have been substantial changes in the underlying structure of the Celtic Sea fish community and not simply a change in fishery preferences. 6We suggest that the reported changes in trophic structure result from reductions in the spawning stock biomass of traditional target species associated with intensive fishing, together with long-term climate variability. 7The relative distribution of fish market prices has changed significantly over the past 22 years, with high trophic level species experiencing greater price rises than lower trophic level species. 8Although decreased abundance of high trophic level species will ultimately have negative economic consequences, the reduction in mean trophic level of the fish community as a whole may allow the system to sustain higher fishery yields. 9Management objectives in this fishery will depend on the relative values that society attaches to economic profit and protein production. [source] Young People's Musical Taste: Relationship With Gender and Gender-Related Traits,JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 8 2008Ann Colley The present study extended previous findings of gender differences in young people's musical taste by examining whether identification with gender-related expressive or instrumental traits contributes to these differences, and by examining the underlying structure of musical taste by gender. The results confirmed greater liking of heavier contemporary music among men and of chart pop music among women. Gender was a stronger predictor of taste for gender-stereotyped styles than identification with gender-related traits. The structure of style preferences in dimensions relating to mainstream styles varied by gender. Men and participants with higher scores on expressiveness gave higher ratings to more styles. The findings are discussed in relation to gender differences in the use of music and gender-role socialization. [source] Guidelines for assessment of bone microstructure in rodents using micro,computed tomographyJOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2010Mary L Bouxsein Abstract Use of high-resolution micro,computed tomography (µCT) imaging to assess trabecular and cortical bone morphology has grown immensely. There are several commercially available µCT systems, each with different approaches to image acquisition, evaluation, and reporting of outcomes. This lack of consistency makes it difficult to interpret reported results and to compare findings across different studies. This article addresses this critical need for standardized terminology and consistent reporting of parameters related to image acquisition and analysis, and key outcome assessments, particularly with respect to ex vivo analysis of rodent specimens. Thus the guidelines herein provide recommendations regarding (1) standardized terminology and units, (2) information to be included in describing the methods for a given experiment, and (3) a minimal set of outcome variables that should be reported. Whereas the specific research objective will determine the experimental design, these guidelines are intended to ensure accurate and consistent reporting of µCT-derived bone morphometry and density measurements. In particular, the methods section for papers that present µCT-based outcomes must include details of the following scan aspects: (1) image acquisition, including the scanning medium, X-ray tube potential, and voxel size, as well as clear descriptions of the size and location of the volume of interest and the method used to delineate trabecular and cortical bone regions, and (2) image processing, including the algorithms used for image filtration and the approach used for image segmentation. Morphometric analyses should be based on 3D algorithms that do not rely on assumptions about the underlying structure whenever possible. When reporting µCT results, the minimal set of variables that should be used to describe trabecular bone morphometry includes bone volume fraction and trabecular number, thickness, and separation. The minimal set of variables that should be used to describe cortical bone morphometry includes total cross-sectional area, cortical bone area, cortical bone area fraction, and cortical thickness. Other variables also may be appropriate depending on the research question and technical quality of the scan. Standard nomenclature, outlined in this article, should be followed for reporting of results. © 2010 American Society for Bone and Mineral Research [source] A weak degeneracy revealing decomposition for the CANDECOMP/PARAFAC modelJOURNAL OF CHEMOMETRICS, Issue 2 2010Roberto Rocci Abstract The CANDECOMP/PARAFAC (CP) model is a well known and frequently used tool for extracting substantial information from a three-way data array. It has several useful characteristics and usually gives meaningful insights about the underlying structure of the data. However, in some cases it has a ,strange' behaviour suffering from the so-called ,degenerate solutions', i.e. solutions where the components show a diverging pattern and are meaningless. Several authors have investigated the causes of degeneracy concluding that the phenomenon is due to a lack of minimum of the loss function. In this paper, we study the degeneracy of CP limiting our attention to the two-component case. The study is done by introducing a canonical form, called 2DR, which is ,weakly degeneracy revealing'. On the ground of this framework, degeneracy is studied along with some of the remedies proposed in the literature by using a Tucker3 model having a core in the 2DR form. The analysis gives new insights about the behaviour of the CP model and suggests new ideas on how to deal with degeneracy. Copyright © 2010 John Wiley & Sons, Ltd. [source] Three-way component analysis of interval-valued dataJOURNAL OF CHEMOMETRICS, Issue 5 2004Paolo Giordani Abstract Vertices Principal Component Analysis (V-PCA) and Centers Principal Component Analysis (C-PCA) are variants of Principal Component Analysis (PCA) to deal with two-way interval-valued data. In this case the observation units are represented as hyperrectangles instead of points. Tucker3 and CANDECOMP/PARAFAC are component analysis techniques to analyze the underlying structure of three-way data sets. In the present paper, after recalling the above mentioned methods, we extend the C-PCA and V-PCA methods to deal with three-way interval-valued data by means of Tucker3 and CANDECOMP/PARAFAC and we describe how to represent the observation units in the obtained low-dimensional space. Furthermore, an application of the extended methods,called Three-way Vertices Principal Component Analysis (3V-PCA) and Three-way Centers Principal Component Analysis (3C-PCA),to three-way interval-valued air pollution data is described. Copyright © 2004 John Wiley & Sons, Ltd. [source] A Simple Laboratory Exercise in Food Structure/Texture Relationships Using a Flatbed ScannerJOURNAL OF FOOD SCIENCE EDUCATION, Issue 1 2002D.W. Stanley ABSTRACT: A laboratory experiment is described that has been designed to allow students to gather meaningful structural and mechanical data with limited equipment. Images are acquired using a computer-interfaced flatbed scanner. Although intended for bread, this approach can be applied to other food products as well. This experiment may be as broad or narrow and as complex or simple as desired. Students have the decided advantage of gathering data themselves, not merely viewing a demonstration of expensive research-grade instrumentation. Experience with image analysis software facilitates a better understanding of quantifying structural data than can be obtained from lecture or text material. Students should become aware of the dependence a specific property, texture, on the underlying structure of food materials and gain an appreciation of the role food structure has in determining many quality parameters. [source] A simultaneous test of unit root and level changeJOURNAL OF FORECASTING, Issue 3 2010Duk Bin Jun Abstract Testing the existence of unit root and/or level change is necessary in order to understand the underlying processes of time series. In many studies carried out so far, the focus was only on a single aspect of unit root and level change, therefore limiting a full assessment of the given problems. Our study aims to find a solution to the given problems by testing the two hypotheses simultaneously. We derive the likelihood ratio test statistic based on the state space model, and their distributions are created by the simulation method. The performance of the proposed method is validated by simulated time series and also applied to two Korean macroeconomic time series to confirm its practical application. This analysis can provide a solution to determine the underlying structure of arguable time series. Copyright © 2009 John Wiley & Sons, Ltd. [source] Density functional study of graphene overlayers on SiCPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 7 2008Alexander Mattausch Abstract Despite the ongoing "graphene boom" of the last three years our understanding of epitaxial graphene grown on SiC substrate is only beginning to emerge. Along with experimental methods such as low energy electron diffraction (LEED), scanning tunneling microscopy (STM) and angle resolved photoemission spectroscopy (ARPES), ab initio calculations help to uncover the geometric and electronic structure of the graphene/SiC interface. In this chapter we describe the density-functional calculations we performed for single and double graphene layers on Si- and C-terminated 6H-SiC surfaces. Experimental data reveal a pronounced difference between the two surface terminations. On a Si-terminated surface the interface adopts a 6,3 × 6,3 unit cell whereas the C-face supports misoriented (turbostratic) graphene layers. It has been recently realized that, on the Si-face, the large commensurate cell is subdivided into patches of coherently matching to the substrate carbon atoms. In our calculations we assumed the "coherent match" geometry for the whole interface plane. This reduces the periodic unit to the ,3 × ,3R 30° cell but requires a substantial stretching of the graphene sheet. Although simplified, the model provides a qualitative picture of the bonding and of the interface electron energy spectrum. We find that the covalent bonding between the carbon layer and the substrate destroys the massless "relativistic" electron energy spectrum, the hallmark of a freestanding graphene. Hence the first carbon layer cannot be responsible for the graphene-type electron spectrum observed by ARPES and rather plays a role of a buffer between the substrate and the subsequent carbon sheets. The "true" graphene spectrum appears with the second carbon layer which exhibits a weak van der Waals bonding to the underlying structure. For Si-terminated substrate, we find that the Fermi level is pinned by the interface state at 0.45 eV above the graphene Dirac point, in agreement with experimental data. This renders the interface metallic. On the contrary, for a C-face the "coherent match" model predicts the Fermi level exactly at the Dirac point. However, this does not necessarily apply to the turbostratic graphene layers that normally grow on the C-terminated substrate. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Public Opinion and the Contradictions of Jimmy Carter's Foreign PolicyPRESIDENTIAL STUDIES QUARTERLY, Issue 4 2000ANDREW Z. KATZ President Jimmy Carter's failure to achieve popular support for his foreign policy is commonly attributed to his disregard of public opinion. The author evaluates this perception by examining the Carter administration's use of polls in the areas of human rights and U.S.-Soviet relations. Archival material confirms that Carter did not ignore public opinion; rather, his polling operation did not provide the White House with a complete and objective portrait of public attitudes. Carter's team assumed that public opinion on foreign policy was malleable and lacked structure. Thus, no effort was made to determine whether the contradictions pollsters found on the surface were actually held together by an underlying structure. Therefore, the Carter White House had neither an accurate gauge of public attitudes nor an understanding of those attitudes sufficient to build support for its policies. [source] Development of a disease specific questionnaire to supplement a generic tool for QoL in colorectal cancerPSYCHO-ONCOLOGY, Issue 7 2003J. Davidson-Homewood The need for disease-specific quality of life measures is highlighted in the literature. The psychometric properties of a supplementary disease-specific quality of life questionnaire developed for use with a generic Quality of Life tool in colorectal cancer patients are explored. Originally developed and tested in a German sample, the English translation was tested on a cohort of UK colorectal cancer patients. Relevance and acceptability was previously established in Germany. A rigorous factor analysis ascertained the underlying structure of two factors with a number of single items that were retained as clinically important symptom indicators. In considering validity, four conditions were assessed: Reliability using Cronbach's alpha; Construct validity by comparing patient subgroups; Clinical Validity, by testing the hypothesis that some patient subgroups experience worse quality of life; Construct Reliability using second order factor analysis with the EORTC QOLQ-C30 scales, confirming that the factors retained provide an excellent measure of physical discomfort and a good measure of physical well being. Two other such questionnaires were developed in parallel with this one and reported in the literature (FACT-C and QOLQ-CR38). However, this questionnaire provides a useful alternative tool for use in clinical trials of colorectal cancer treatments alongside a core QoL questionnaire especially when brevity is an important consideration. Copyright © 2003 John Wiley & Sons, Ltd. [source] The Infrastructure of StabilityARCHITECTURAL DESIGN, Issue 5 2010Tarsha Finney Abstract Afghanistan's key strategical position, lying between Asia and the Middle East, has made it prey to foreign invasion throughout its history. TarshaFinney explains how an existing military infrastructure of airports, roads, accommodation and unskilled concentrations of labour have given the US and its allies an important leg-up in the current conflict, providing what could be perceived to be an underlying structure of stability. Copyright © 2010 John Wiley & Sons, Ltd. [source] Role of crustal anisotropy in modifying the structural and sedimentological evolution of extensional basins: the Gamtoos Basin, South AfricaBASIN RESEARCH, Issue 3 2004Douglas A. Paton Through the investigation of crustal heterogeneities, sedimentary basin architecture and seismic stratigraphy, we demonstrate how a crust-scale anisotropy controls the initiation of rifting and the subsequent structural and sedimentological evolution of the Mesozoic Gamtoos Basin, southern South Africa. The results demonstrate that the >90-km-long Gamtoos Fault established its length very early in its syn-rift phase (within ,5 Ma of rift initiation) before accruing over 6 s (two-way-travel time (TWT)), or >12 km, of displacement without any significant subsequent increase in length. In addition, there is no evidence at the resolution of the data of fault segmentation, isolated depocentres nor of intra-basin faults progressively coalescing during the syn-rift interval. The early establishment of length resulted in a rapid transition from a terrestrial depositional environment to anoxic, deep marine conditions. The Gamtoos Fault has a 90° bend in the fault trace that we propose is inherited from the underlying structure. Immediately adjacent to the bend the basin-fill is significantly deformed and a high-amplitude (>1.7s TWT) monoclinal fold is observed. Previous workers proposed that the fold was a consequence of a complex interplay between compression and extension. Through a restoration of the basin-fill deformation we produce a model that suggests that the fold is a consequence of the accommodation of extension by the unusual plan-view trace of the fault. The evolution of the basin does not conform to current fault growth models and it is proposed that its unusual and complex development can be attributed to the underlying crustal-scale anisotropy, a fact that is likely to be important in other areas in which crustal stretching is superimposed on heterogeneous continental crust. [source] Bayesian Finite Markov Mixture Model for Temporal Multi-Tissue Polygenic PatternsBIOMETRICAL JOURNAL, Issue 1 2009Yulan Liang Abstract Finite mixture models can provide the insights about behavioral patterns as a source of heterogeneity of the various dynamics of time course gene expression data by reducing the high dimensionality and making clear the major components of the underlying structure of the data in terms of the unobservable latent variables. The latent structure of the dynamic transition process of gene expression changes over time can be represented by Markov processes. This paper addresses key problems in the analysis of large gene expression data sets that describe systemic temporal response cascades and dynamic changes to therapeutic doses in multiple tissues, such as liver, skeletal muscle, and kidney from the same animals. Bayesian Finite Markov Mixture Model with a Dirichlet Prior is developed for the identifications of differentially expressed time related genes and dynamic clusters. Deviance information criterion is applied to determine the number of components for model comparisons and selections. The proposed Bayesian models are applied to multiple tissue polygenetic temporal gene expression data and compared to a Bayesian model-based clustering method, named CAGED. Results show that our proposed Bayesian Finite Markov Mixture model can well capture the dynamic changes and patterns for irregular complex temporal data (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Application of Multivariate Analysis to Optimize Function of Cultured HepatocytesBIOTECHNOLOGY PROGRESS, Issue 2 2003Christina Chan Understanding the metabolic and regulatory pathways of hepatocytes is important for biotechnological applications involving liver cells, including the development of bioartificial liver (BAL) devices. To characterize intermediary metabolism in the hepatocytes, metabolic flux analysis (MFA) was applied to elucidate the changes in intracellular pathway fluxes of primary rat hepatocytes exposed to human plasma and to provide a comprehensive snapshot of the hepatic metabolic profile. In the current study, the combination of preconditioning and plasma supplementation produced distinct metabolic states. Combining the metabolic flux distribution obtained by MFA with methodologies such as Fisher discriminant analysis (FDA) and partial least squares or projection to latent structures (PLS) provided insights into the underlying structure and causal relationship within the data. With the aid of these analyses, patterns in the cellular response of the hepatocytes that contributed to the separation of the different hepatic states were identified. Of particular interest was the recognition of distal pathways that strongly correlated with a particular hepatic function. The hepatic functions investigated were intracellular triglyceride accumulation and urea production. This study illustrates a framework for optimizing hepatic function and a possibility of identifying potential targets for improving hepatic functions. [source] Neuropsychological symptom dimensions in bipolar disorder and schizophreniaBIPOLAR DISORDERS, Issue 1-2 2007Pál Czobor Background:, While neurocognitive (NC) impairments have been well documented in schizophrenia (SZ), there is limited data as to whether similar impairments are present in other persistent mental illnesses. Recent data indicate that NC impairments may be manifested in bipolar disorder (BPD) and that they persist across disease states, including euthymia. An important question is whether a comparable structure of NC impairments is present in the 2 diagnostic groups. Objective:, In a previous factor analytic study, we identified 6 factors to describe the basic underlying structure of neuropsychological (NP) functioning in SZ: Attention, Working Memory, Learning, Verbal Knowledge, Non-Verbal Functions, Ideational Fluency. The goal of this study was to investigate whether this factor structure is generalizable for BPD. Methods:, The BPD sample included patients (n = 155) from an ongoing longitudinal study evaluating BPD at the time of hospitalization for relapse and at multiple time points over the following 2 years. The SZ sample included patients (n = 250) from a 3-year study. For the current examination the baseline NP evaluations were selected for both samples. Results:, Exploratory and confirmatory factor analyses in the BPD sample yielded factors similar to those identified in the SZ sample. The coefficients of congruence ranged between 0.66,0.90 for the individual factors, indicating a good overall correspondence between the factor structures in the 2 diagnostic groups. Analysis of covariance (ANCOVA) analysis with education level, full scale-IQ, gender and ethnicity as covariates indicated that SZ patients had markedly worse performance on the Attention and Non-Verbal Functioning factors compared to the BPD patients. Conclusions:, Together, these data suggest that while the same underlying factor structure describes NP functioning in both groups, the profile of impairments appears to vary with the diagnosis. [source] Radiographic and Computed Tomographic Studies of Calcium Hydroxylapatite for Treatment of HIV,Associated Facial Lipoatrophy and Correction of Nasolabial FoldsDERMATOLOGIC SURGERY, Issue 2008ALASTAIR CARRUTHERS MD OBJECTIVES This study sought to assess the radiographic appearance produced by calcium hydroxylapatite soft tissue filler (CaHA; Radiesse, BioForm Medical Inc.) following augmentation to correct the nasolabial folds or facial wasting associated with human immunodeficiency virus lipoatrophy. METHODS A total of 58 patients, with either lipoatrophy or pronounced nasolabial folds, were treated with CaHA. Radiographic (X-ray) and computed tomographic (CT) imaging studies were conducted pre- and posttreatment in most patients; the images were sent to an independent laboratory to be analyzed by two evaluators who were board-certified radiologists and blinded to study purpose, product, and patient condition. RESULTS While results for X-ray evaluation showed inconsistencies in visualization of CaHA, CT scans showed consistent visualization in nearly all cases in patients who were imaged immediately after treatment. In addition, the results indicated no obscuration of underlying structures by CaHA and no evidence of CaHA migration. CONCLUSIONS Earlier clinical trials established CaHA as a safe and effective soft tissue filler. This CaHA study shows no overt radiographic safety concerns. CaHA is unlikely to be confused with conventional abnormal and adverse radiographic findings. The product is not always visible on X-ray. Although usually visible on CT scans, its appearance is distinct from surrounding bony structures and does not interfere with normal analysis. In addition, the product does not obscure underlying structures on CT scans. [source] Preferences for colours and colour--emotion combinations in early childhoodDEVELOPMENTAL SCIENCE, Issue 4 2001Marcel R. Zentner Previous research has shown that, by the age of 3 to 4 years, children rely not only on perceptual similarity but also on shared category or other underlying structures to draw analogies. The present study extends this work by showing that children as young as 3 years old detect consistent relationships between colours and facial expressions of emotions , two phenomena that share no physical characteristics, violate conventional categories and have no obvious environmental contiguity. Two explanatory hypotheses are put forward: (a) learning by convention, which is explored against the standard of adults' and older children's matching patterns, and (b) reliance upon a common underlying but perceptually unavailable dimension , operationalized in terms of emotion and colour preferences in the context of the present study. Both explanatory approaches are discussed and avenues for future work are suggested. [source] Testing etching hypothesis for the shaping of granite dome structures beneath lateritic weathering landsurfaces using ERT methodEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2003Anicet Beauvais Abstract An Erratum has been published for this article in Earth Surface Processes and Landforms 28(13) 2003, 1491. Granite domes, boulders and knobs buried within saprolite have been detected beneath lateritic weathering landsurfaces using 2D electrical resistivity tomography (ERT). This technique provides a valuable means of mapping the bedrock topography and the regolith structures underneath landsurfaces, as it is intrinsically very sensitive to the electrical properties of superimposed pedological, hydrological and geological layers, allowing the determination of their relative geometry and spatial relationships. For instance, 2D inverse electrical resistivity models including topographic data permit the de,nition of lithostratigraphic cross-sections. It shows that resistive layers, such as the more or less hardened ferruginous horizons and/or the bedrock, are generally well differentiated from poorly resistive layers, such as saprolite, including water-saturated lenses, as has been corroborated by past and actual borehole observations. The analysis of the 2D geometrical relations between the weathering front, i.e. the bedrock topography, and the erosion surface, i.e. the landsurface topography, documents the weathering and erosion processes governing the development of the landforms and the underlying structures, thus allowing the etching hypothesis to be tested. The in,ltration waters are diverted by bedrock protrusions, which behave as structural thresholds compartmentalizing the saprolite domain, and also the regolith water table, into distinct perched saturated subdomains. The diverted waters are thus accumulated in bedrock troughs, which behave like underground channels where the saprolite production rate may be enhanced, provided that the water drainage is ef,cient. If the landsurface topography controls the runoff dynamics, the actual bedrock topography as depicted by ERT imaging in,uences the hydrodynamics beneath the landsurface. In some way, this may control the actual weathering rate and the shaping of bedrock protrusions as granite domes and knobs within thick saprolite, before their eventual future exposure. Copyright © 2003 John Wiley & Sons, Ltd. [source] Flexible querying of semistructured data: A fuzzy-set-based approachINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 7 2007Martine De Calmès This article provides a general discussion about how flexible querying can be applied to semistructured data (SSD). We adapt flexible querying ideas, already used for classically structured databases, to XQuery-like querying of SSD for managing users' priority and preferences, but also for tackling with the variability of SSD underlying structures. Indeed flexible querying seems to be still more useful for SSD than for classical databases, because of the potential structural heterogeneity of the former. Fuzzy sets are useful for expressing flexible requirements on attribute values and for estimating the degree of similarity of tags, or attribute labels, with elements present in the request. Priorities are introduced in the request for specifying the relative importance of elementary requirements in terms of their semantic contents, but also preferences about the location of information in the structure. The evaluation of the queries uses a qualitative scale with a finite number of levels, and retrieved pieces of SSD are rank-ordered using a lexicographic vector procedure. Illustrative examples are provided. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 723,737, 2007. [source] Dynamics of mucosal dimensions after root coverage with a bioresorbable membraneJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2000Hans-Peter Müller Abstract Background: So far, the clinical effects of the placement of a resorbable membrane for guided tissue regeneration have not been studied in humans in great detail. The dynamics of the resorptive processes, in particular, appear to be rather speculative. In the present longitudinal study, specific alterations of the dimensions of the dentogingival mucosa were explored after surgical root coverage by using a bioresorbable membrane and a coronally-repositioned flap. Methods: The study population consisted of 14 patients with a total of 31 predominantly shallow, Miller class I, II or III recessions. The thickness of the masticatory and lining mucosa before and after surgical intervention was measured with an ultrasonic device. Results: Mean (±sd) recession depth and width were 2.85±1.29 and 4.46±1.14 mm, respectively. After 12 months, 51±29% of the recession depth (p<0.001) and 13±35% of its width (n.s.) were covered. Root coverage seems to be rather defect-type sensitive with best results obtained at canines with relatively shallow recessions. Mucosal thickness was considerably increased after surgery with a gradual decrease during the following 9 months. Thus, thickness of the marginal tissue rose from 0.82±0.27 mm to 1.49±0.54 mm 3 months after placement of the membrane (p<0.001). After 12 months, a mean thickness of 1.03±0.40 mm was observed (p<0.001). Even more pronounced alterations were noted for the alveolar lining mucosa with a threefold increase of thickness 3 months after surgery and a gradual decrease to about 1 mm after 12 months. Conclusions: The present results point to the considerable space making capacity of the bioresorbable membrane which probably allows for the ingrowth of a granulation tissue derived from the underlying structures. The gradual decline in mucosal thickness between months 6 and 9 after surgery may be paralleled by the maturation of the granulation tissue while complete resorption of the membrane had been accomplished. [source] A non-Gaussian generalization of the Airline model for robust seasonal adjustmentJOURNAL OF FORECASTING, Issue 5 2006JOHN A. D. ASTON Abstract In their seminal book Time Series Analysis: Forecasting and Control, Box and Jenkins (1976) introduce the Airline model, which is still routinely used for the modelling of economic seasonal time series. The Airline model is for a differenced time series (in levels and seasons) and constitutes a linear moving average of lagged Gaussian disturbances which depends on two coefficients and a fixed variance. In this paper a novel approach to seasonal adjustment is developed that is based on the Airline model and that accounts for outliers and breaks in time series. For this purpose we consider the canonical representation of the Airline model. It takes the model as a sum of trend, seasonal and irregular (unobserved) components which are uniquely identified as a result of the canonical decomposition. The resulting unobserved components time series model is extended by components that allow for outliers and breaks. When all components depend on Gaussian disturbances, the model can be cast in state space form and the Kalman filter can compute the exact log-likelihood function. Related filtering and smoothing algorithms can be used to compute minimum mean squared error estimates of the unobserved components. However, the outlier and break components typically rely on heavy-tailed densities such as the t or the mixture of normals. For this class of non-Gaussian models, Monte Carlo simulation techniques will be used for estimation, signal extraction and seasonal adjustment. This robust approach to seasonal adjustment allows outliers to be accounted for, while keeping the underlying structures that are currently used to aid reporting of economic time series data.,,Copyright © 2006 John Wiley & Sons, Ltd. [source] Treatment of basal cell carcinomas in patients with nevoid basal cell carcinoma syndromeJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2009S Van Der Geer Abstract Background, Nevoid basal cell carcinoma syndrome (NBCCS) is characterized by the development of multiple basal cell carcinomas (BCCs). A major problem for these patients is the enormous amount of BCCs which can invade in the deep underlying structures, especially in the face. Different treatment modalities are used in these patients; surgical excision, Mohs micrographic surgery, cryotherapy, photodynamic therapy, ablative laser therapy and topical 5% imiquimod. There is no evidence based advice how to treat a NBCCS patient. Objective, To give a review of the literature about the possible treatment modalities for the multiple BCCs in NBCCS patients. Results, Literature consists mainly of case reports; no evidence based advice how to treat a NBCCS patient exists. Multiple treatments are available (surgical and non-surgical), and a lot of them can be combined. Treatment in a megasession is an option to diminish the medical and social inconvenience for the patient. Conflicts of interest None declared [source] | |||||||||||||||||||||||||||||||