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At least 19 recordsLinked to original sources

KG-Microbe: Building modular and scalable knowledge graphs for microbiome and microbial sciences.

BACKGROUND: The integration of many disparate forms of data is essential for understanding the microbial world and its interaction with the environment and human health. Doing so is particularly challenging in the context of microbe-host and microbe-microbe interactions that contribute to health or environmental outcomes. There are thousands of relevant microbial species, and millions of interactions among those microbes and with their environment or host. Integrated information (e.g., about host and microbial physiology, genetics, and metabolism) facilitates deeper understanding of complex mechanisms and helps interpret correlative results. RESULTS: The KG-Microbe construction framework is a novel approach to harmonizing bacterial and archaeal data in the form of a findable, accessible, interoperable, reusable and AI-ready knowledge graph (KG). Starting from a core KG with organismal traits, environments, and growth preferences and the integration of established ontologies, the framework generates a hierarchy of related KGs targeting specific use cases, including the human microbiome in the context of disease, or environmental microbiomes. The framework supports customizable taxa subsets representing communities or clades of interest. Evaluations of the KG-Microbe KGs through a series of competency questions demonstrate the accuracy and effectiveness of the data harmonization, and the utility of the resulting KGs in studies of inflammatory bowel disease and Parkinson's disease. Finally, the predictive and environmental capabilities of the KGs are demonstrated by predicting growth preferences using graph features. CONCLUSIONS: The KG-Microbe framework unifies microbial contexts in a single resource to support integrative analyses across biomedical, host, and environmental domains. KG-Microbe is a flexible, modular enabling technology for humans and machine learning methods to uncover candidate mechanistic explanations of microbial associations.

Microbiota↗

The semantic pathfinder: using an authoring metaphor for generic multimedia indexing.

This paper presents the semantic pathfinder architecture for generic indexing of multimedia archives. The semantic pathfinder extracts semantic concepts from video by exploring different paths through three consecutive analysis steps, which we derive from the observation that produced video is the result of an authoring-driven process. We exploit this authoring metaphor for machine-driven understanding. The pathfinder starts with the content analysis step. In this analysis step, we follow a data-driven approach of indexing semantics. The style analysis step is the second analysis step. Here, we tackle the indexing problem by viewing a video from the perspective of production. Finally, in the context analysis step, we view semantics in context. The virtue of the semantic pathfinder is its ability to learn the best path of analysis steps on a per-concept basis. To show the generality of this novel indexing approach, we develop detectors for a lexicon of 32 concepts and we evaluate the semantic pathfinder against the 2004 NIST TRECVID video retrieval benchmark, using a news archive of 64 hours. Top ranking performance in the semantic concept detection task indicates the merit of the semantic pathfinder for generic indexing of multimedia archives.

Abstracting and Indexing↗

Toward a model of false recall: experimental manipulation of encoding context and the collection of verbal reports.

The likelihood of false recall in the Deese-Roediger-McDermott (DRM) paradigm was shown to depend on encoding context in two experiments. When fillers had been preselected to decrease the likelihood of encoding the critical lure's semantic features, false recall was virtually eliminated. However, when the same words were presented rearranged in different presentation orders, levels of false recall that were found in earlier DRM studies (Robinson & Roediger, 1997) were replicated. The role of encoding processes in the DRM paradigm was further explored with additional participants completing the experiment while thinking aloud. During encoding of word lists, participants verbalized semantic elaboration of the critical lure while studying the word lists. A path analysis demonstrated that participants' verbalization of critical lures during encoding reliably predicted their level of false recall.

Adult↗

Functional network differences in schizophrenia: a rCBF study of semantic processing.

Studies of regional cerebral blood flow in patients with schizophrenia have led to the idea that dysfunctional neurocircuitry may play a role in patients' cognitive deficits. The present PET study was designed to explore this idea by comparing the functional neural networks associated with semantic processing for patients and normal controls through structural equation modeling (path analysis). The patients showed significantly different neural interactions among frontal regions, between the frontal and temporal cortices, and between the frontal lobe and anterior cingulate than controls. These discrepancies were especially striking given there were minimal group differences in task performance. Results suggest that schizophrenia involves a neural abnormality that is evident in functional networks during cognitive performance.

Adult↗

Semantic re-interpretation and garden path recovery.

Participant's eye-movements were recorded while they read locally ambiguous sentences. Evidence for processing difficulty was found when the interpretation of the initially preferred misanalysis clashed with that of the globally correct analysis, demonstrating the persistence of the earlier interpretation. Processing difficulty associated with the syntactic reanalysis was largely localised to the disambiguating region, with difficulty due to semantic persistence occurring later. The results show that semantic persistence is not limited to extreme cases of parse failure, and can occur even when reanalysis is relatively straightforward.

Attention↗

Learning-related neuronal responses in prefrontal cortex studied with functional neuroimaging.

We assessed time-dependent neuronal activity accompanying learning using functional magnetic resonance imaging (fMRI). An artificial grammar learning paradigm enabled us to dissociate activations associated with individual item learning from those involved in learning the underlying grammar system. We show that a localized region of right prefrontal cortex (PFC) is preferentially sensitive to individual item learning during the early stages of the experiment, while the left PFC region is sensitive to grammar learning which occurred across the entire course of the experiment. In addition to dissociating these two types of learning, we were able to characterize the effect of rule acquisition on neuronal responses associated with explicit learning of individual items. This effect was expressed as modulation of the time-dependent right PFC activations such that the early increase in activation associated with item learning was attenuated as the experiment progressed. In a further analysis we used structural equation modelling to explore time-dependent changes in inter-regional connectivity as a function of both item and grammar rule learning. Although there were no significant effects of item learning on the measured path strengths, rule learning was associated with a decrease in right fronto-parietal connectivity and an increase in connectivity between left and right PFC. Further fronto-parietal path strengths were observed to change, with an increase in left fronto-parietal and a decrease in right fronto-parietal connectivity path strength from right PFC to left parietal cortex. We interpret our findings in terms of a left frontal system mediating the semantic analysis of study items and directly influencing a right fronto-parietal system associated with episodic memory retrieval.

Adult↗

Self-esteem, ethnic identity, and behavioral adjustment among Anglo and Chicano adolescents in West Texas.

This study provides a comparison of similarities and differences with respect to ethnic identity between Anglo and Chicano adolescents from Texas. A path analysis model was used to test a theoretical assumption concerning proposed antecedents and consequences of self-esteem. Research instruments included the Rosenberg Self Esteem Scale, the Semantic Differential (scales for Myself and My Ethnic Group) and the McGuire White Measure of Social Status. Results were consistent with the interpretation that there is a relationship between being Chicano and having lower self-esteem, lower behavioral adjustment, and higher ethnic esteem. The prediction that ethnic esteem would mediate between ethnic group and self-esteem was upheld. Variables such as ethnic group membership per se and sex appear as or more important to the prediction of behavioral level. Clinical implications include recognizing that Chicanos low in self-esteem or behavioral adjustment should not automatically be considered unusual. The problems faced by this group are considered as having something in common with other groups of people who have more problems, lesser status, fewer resources, and fewer sources of available help.

Adolescent↗

Exploring the influence of vocal emotion expression on communicative effectiveness.

This study explores whether speaker emotion influences communicative effectiveness. Two hundred participants rated their current emotional state and gave a description of a route on a simple map. The quality of the linguistic content of the descriptions was assessed using Latent Semantic Analysis. Six hundred participants provided route drawings based on the map descriptions. Median route deviation served as a measure of communicative effectiveness. Eighty additional participants rated invariant parts of the descriptions for perceived speaker happiness. Path analysis revealed that while speaker emotion did not affect the linguistic content of the descriptions, it had an effect on communicative effectiveness both through the effects of vocal cues directly as well as mediated by perceived happiness of speech. Specifically, higher first formants were associated with higher reported and perceived happiness as well as higher communicative effectiveness. Jitter, on the other hand, was negatively related to the perception of happiness and positively related to communicative effectiveness. These findings suggest that mood-related modulation of phonation and articulation can influence the effectiveness of communication in addition to message content.

Adolescent↗

Processing the noun phrase versus sentence coordination ambiguity: thematic information does not completely eliminate processing difficulty.

When faced with the noun phrase (NP) versus sentence (S) coordination ambiguity as in, for example, The thief shot the jeweller and the cop ..., readers prefer the reading with NP-coordination (e.g., "The thief shot the jeweller and the cop yesterday") over one with two conjoined sentences (e.g., "The thief shot the jeweller and the cop panicked"). A corpus study is presented showing that NP-coordinations are produced far more often than S-coordinations, which in frequency-based accounts of parsing might be taken to explain the NP-coordination preference. In addition, we describe an eye-tracking experiment investigating S-coordinated sentences such as Jasper sanded the board and the carpenter laughed, where the poor thematic fit between carpenter and sanded argues against NP-coordination. Our results indicate that information regarding poor thematic fit was used rapidly, but not without leaving some residual processing difficulty. This is compatible with claims that thematic information can reduce but not completely eliminate garden-path effects.

Analysis of Variance↗

Assessing semantic similarity measures for the characterization of human regulatory pathways.

MOTIVATION: Pathway modeling requires the integration of multiple data including prior knowledge. In this study, we quantitatively assess the application of Gene Ontology (GO)-derived similarity measures for the characterization of direct and indirect interactions within human regulatory pathways. The characterization would help the integration of prior pathway knowledge for the modeling. RESULTS: Our analysis indicates information content-based measures outperform graph structure-based measures for stratifying protein interactions. Measures in terms of GO biological process and molecular function annotations can be used alone or together for the validation of protein interactions involved in the pathways. However, GO cellular component-derived measures may not have the ability to separate true positives from noise. Furthermore, we demonstrate that the functional similarity of proteins within known regulatory pathways decays rapidly as the path length between two proteins increases. Several logistic regression models are built to estimate the confidence of both direct and indirect interactions within a pathway, which may be used to score putative pathways inferred from a scaffold of molecular interactions.

Databases, Protein↗

Regressive eye movements and sentence parsing: on the use of regression-contingent analyses.

Altmann, Garnham, and Dennis (1992) recently advocated the use of a regression-contingent analysis in eye movement studies dealing with parsing of sentences containing temporary structural ambiguities. Using experimental sentences preceded by referentially supportive contexts, they demonstrated a different pattern of results when regressive eye movements were eliminated from the data set than when regressions were included. The regression-contingent analysis that they used involves an implicit assumption that regressive eye movements are a necessary consequence of subjects' being garden pathed. We report some data which demonstrate that garden path effects are sometimes even stronger in the absence of regressions and, thus, argue that readers can be garden pathed without making regressions.

Attention↗

Differential age effects in semantic and episodic memory.

Results from 4 experimental tasks and 8 data sets (the 4 tasks involved either multiple sessions or different stimuli) as well as a vocabulary test conducted on the same 80 participants (40 younger and 40 older adults) are reported. The authors employed 2 semantic memory tasks (lexical decision and multiplication verification) using data from 2 sessions (for a total of 4 semantic data sets) and 2 episodic memory tasks (hybrid visual search and memory search with digits and with words as stimuli). Factor analyses using slope and intercept data from the 8 experimental data sets indicated the presence of 3 latent factors: a single intercept factor for both episodic and semantic tasks and separate slope factors for episodic and semantic tasks. A structural equation model with paths from age to 3 different 1st-order latent factors (episodic central processes, semantic central processes, and combined episodic and semantic peripheral processes) fit better than general factor models. These data are consistent with a theoretical framework in which there are age-related dissociations between peripheral and central processes across semantic and episodic memory.

Adolescent↗

When Broca experiences the Janus syndrome: an ER-fMRI study comparing sentence comprehension and cognitive sequence processing.

The determining of brain regions that exhibit specific activity during sentence comprehension compared to other non-linguistic cognitive tasks constitutes one of the important challenges in the domain of functional neuroimaging of the faculty of language. In the current paper we report an event-related functional magnetic resonance imaging (ER-fMRI) experiment, in which we directly compared the cerebral basis of sentence comprehension on the one hand, and of abstract sequence processing on the other hand. Previous experimental work done in our group, as well as different observations from recent behavioural, neurophysiological and functional neuroimaging experiments led us to propose the hypothesis that both of these tasks would share certain computational properties. Thus, this experiment was designed to show which brain regions would be implicated in both tasks and compare them to brain regions that would be specifically engaged in sentence comprehension. Results from this experiment suggest that distinct sub-regions in the left prefrontal cortex, potentially including Broca's area show distinct activation patterns during both of these tasks. Results are discussed in the context of a construction-based model of sentence processing (see Dominey and Hoen, 2006, this issue) that is based on a dual-path processing mechanism separating function and content information processing. We propose and discuss the hypothesis that subparts of Broca's area BA 44 and BA 45 would respectively be implicated in two different aspects of sentence comprehension: i) a general structure mapping capability and ii) the online integration of semantic representations onto structural constraints.

Adult↗

Putting data integration into practice: using biomedical terminologies to add structure to existing data sources.

A major purpose of biomedical terminologies is to provide uniform concept representation, allowing for improved methods of analysis of biomedical information. While this goal is being realized in bioinformatics, with the emergence of the Gene Ontology as a standard, there is still no real standard for the representation of clinical concepts. As discoveries in biology and clinical medicine move from parallel to intersecting paths, standardized representation will become more important. A large portion of significant data, however, is mainly represented as free text, upon which conducting computer-based inferencing is nearly impossible. In order to test our hypothesis that existing biomedical terminologies, specifically the UMLS Metathesaurus and SNOMED CT, could be used as templates to implement semantic and logical relationships over free text data that is important both clinically and biologically, we chose to analyze OMIM (Online Mendelian Inheritance in Man). After finding OMIM entries' conceptual equivalents in each respective terminology, we extracted the semantic relationships that were present and evaluated a subset of them for semantic, logical, and biological legitimacy. Our study reveals the possibility of putting the knowledge present in biomedical terminologies to its intended use, with potentially clinically significant consequences.

Databases, Genetic↗

[Failure effects and gender differences in perfectionism].

Perfectionism is a dimension which has been studied very little as a separate entity. It is not even considered as a nosological factor. No classification of the medical sciences underlines its importance other than to speak of a personality trait, of an aspect, or of a parameter. Nevertheless, perfectionism is related to multiple disorders such as depression (18, 20, 36), suicide (8, 16, 55), nutritional problems (11, 28), anxiety (3), obsessive-compulsive personality disorder (53), social phobia (2), as well as insomnia (46). Certain authors stress the possible role of perfectionism in the development or the persistence of a substantial number of these disorders (7, 22, 38). Given these facts, it is all the easier to understand the interest shown by clinicians and researchers in the subject. Better detection and evaluation of its impact on behaviour is important in putting therapies in place (6, 53). Relationships between perfectionism and fear of failure have been approached (21, 51, 54). Correlations between perfectionism and high levels of state and trait anxiety have been demonstrated (23). The evaluation of perfectionism has been dealt with very little. Some questionnaires devote a sub-category to it, such as the Eating Disorder Inventory and the Irrational Beliefs Test. However, recently, it has been recognized that perfectionism is a multidimensional construct. Two Multidimensional Perfectionism Scales have been developed and investigated in relative isolation. Frost, Marten, Lahart and Rosenblate defined perfectionism as the setting of excessively high standards for performance associated with critical self-evaluation. Six dimensions are described: concern over making mistakes, high personal standards, parental expectations, parental criticism, doubt about quality of performance and organization. Internal consistency and validity have been established (25, 26). Hewitt and Flett (30, 31, 33, 35) have developed another approach where three dimensions of perfectionism are described: SOP (Self Oriented Perfectionism) related to high standards and self criticism, SPP (Socially Prescribed Perfectionism) related to the need of approval from others and fear of negative evaluation, OOP (Other-Oriented Perfectionism) reflecting a tendency to set high expectations for others and to evaluate them in a demanding way; this component is related, especially for males, to self-esteem, hostility and authoritarianism. Validity and internal consistency have been established too (30, 31, 35). The Frost and al's Multidimensional Perfectionism Scale and the Hewitt and Flett's scales are closely associated, except concerning the OOP. Because this component could provide new information, we have chosen the second scale, referring to the French translation and validation of Labrecque (45). EMP is the French name of MPS; it is a self-report questionnaire of 45 questions, in fact three subscales of 15 items rated on a 7-point Likert-type scale. MPS was administered to 617 first year students at the university of Liège (table II). Differences are considered according to gender and experience of failure i.e. the fact of repeating an academic year. We realized a component analysis with promax rotation. Among the different possibilities offered by the scree-test the choice of a 4 factor solution stresses the original structure: SOP (14 items), SPP (12 items), OOP (9 items) and anti OOP (10 items); the last one is additional but allows for respecting semantics and saturation of the items. The first aim of confirming validity and internal consistency is satisfactory. In other respects the multidimensional structure of the concept leads to consideration of a positive, adaptive perfectionism and a more negative perfectionism, facilitating psychopathology (59, 60, 61). So it seems interesting to compare the different components of MPS in order to find an eventual sex-failure effect. The evaluation of perfectionism is obvious, considering it as a personality trait, but it can be used also in taking into account stress and its impact, for instance that of academic performance (29, 37, 39, 58). Conferring on MPS more pertinence in gender differentiation and failure evaluation is an other goal of this research. Through the particular choice of statistical results, sex and sex-failure effects can be demonstrated: a MANOVA underlines sex effect (lambda de Wilks = 0.96, p = 0.001) and sex-failure effect (lambda de Wilks = 0.98, p = 0.05). Structure of MPS is different in four groups (FE: women with failure, FnE: women without failure, ME: men with failure, MnE: men without failure). ANOVA show differences of MPS3, MPS1 and MPS2. Far more promising is the use of LISREL method allowing for the construction of a coherent model of relationships between some dimensions of MPS and Test-Anxiety, approached here with THEE (test d'habileté aux études et à leur évaluation) French abbreviated version (49) of TASTE (Test for Ability to Study and Evaluation). In fact according to the literature of fear of failure, girls score higher on anxiety and procrastination but less on self-confidence. The structural model shows different pathways, more especially between SPP (socially prescribed perfectionism), T2 (sense of incompetence) and T1 (anxiety). SOP (self oriented perfectionism) and SPP (socially prescribed perfectionism) by girls are very much correlated; it seems that they are more subjected to society and its exigencies of studying but consequently they are more at risk of anxiety and a sense of incompetence. SOP (self oriented perfectionism) by boys functions more indiscriminately of SPP (socially prescribed perfectionism) and is negatively correlated with self-incompetence; boys are more self-confident but they usually procrastinate more probably because failure expectancies would be particularly harmful for their self-esteem; consequently, failure should be related to something else than their own capacity; this may be an explanation of the high rate of male dropouts and failure in the first year at the university of Liège; also a factor explaining the female domination at the university. In the same way the first choice of studies is moving towards shorter and less difficult orientation (46). In case of failure the model is very similar according to gender: SOP (self oriented perfectionism) and T1 (anxiety) are directly connected; SOP and SPP are in this case better correlated by boys but the path between SPP, sense of incompetence and anxiety is less significant than in girls. In conclusion, providing some modifications according to semantics, the choice of a four factor solution allows for confirmation of the original structure of MPS and for internal consistency. The different components of MPS vary according to gender: SOP and more OOP discriminate men and women; SPP allows for differentiating women with failure. A structural model enhances the role of perfectionism in the cognitive and behavioural contexts; for instance it clarifies its action on fear of failure and success rates according to gender.

Adult↗

How good is good enough in path analysis of fMRI data?

This paper is concerned with the problem of evaluating goodness-of-fit of a path analytic model to an interregional correlation matrix derived from functional magnetic resonance imaging (fMRI) data. We argue that model evaluation based on testing the null hypothesis that the correlation matrix predicted by the model equals the population correlation matrix is problematic because P values are conditional on asymptotic distributional results (which may not be valid for fMRI data acquired in less than 10 min), as well as arbitrary specification of residual variances and effective degrees of freedom in each regional fMRI time series. We introduce an alternative approach based on an algorithm for automatic identification of the best fitting model that can be found to account for the data. The algorithm starts from the null model, in which all path coefficients are zero, and iteratively unconstrains the coefficient which has the largest Lagrangian multiplier at each step until a model is identified which has maximum goodness by a parsimonious fit index. Repeating this process after bootstrapping the data generates a confidence interval for goodness-of-fit of the best model. If the goodness of the theoretically preferred model is within this confidence interval we can empirically say that the theoretical model could be the best model. This relativistic and data-based strategy for model evaluation is illustrated by analysis of functional MR images acquired from 20 normal volunteers during periodic performance (for 5 min) of a task demanding semantic decision and subvocal rehearsal. A model including unidirectional connections from frontal to parietal cortex, designed to represent sequential engagement of rehearsal and monitoring components of the articulatory loop, is found to be irrefutable by hypothesis-testing and within confidence limits for the best model that could be fitted to the data.

Adult↗

Overlap in the functional neural systems involved in semantic and episodic memory retrieval.

Neuroimaging and neuropsychological data suggest that episodic and semantic memory may be mediated by distinct neural systems. However, an alternative perspective is that episodic and semantic memory represent different modes of processing within a single declarative memory system. To examine whether the multiple or the unitary system view better represents the data we conducted a network analysis using multivariate partial least squares (PLS ) activation analysis followed by covariance structural equation modeling (SEM) of positron emission tomography data obtained while healthy adults performed episodic and semantic verbal retrieval tasks. It is argued that if performance of episodic and semantic retrieval tasks are mediated by different memory systems, then there should differences in both regional activations and interregional correlations related to each type of retrieval task, respectively. The PLS results identified brain regions that were differentially active during episodic retrieval versus semantic retrieval. Regions that showed maximal differences in regional activity between episodic retrieval tasks were used to construct separate functional models for episodic and semantic retrieval. Omnibus tests of these functional models failed to find a significant difference across tasks for both functional models. The pattern of path coefficients for the episodic retrieval model were not different across tasks, nor were the path coefficients for the semantic retrieval model. The SEM results suggest that the same memory network/system was engaged across tasks, given the similarities in path coefficients. Therefore, activation differences between episodic and semantic retrieval may ref lect variation along a continuum of processing during task performance within the context of a single memory system.

Adult↗

Does it matter what you call it? The relationship between labeling unwanted sexual experiences and distress.

Using cross-sectional data from 2 samples of women attending a university (N = 1,395), the author examined the relationship among women's labeling of their unwanted sexual experiences (USEs) with dating partners and a variety of psychological and school-related outcomes. Three competing path analysis models were tested to determine whether the distress associated with sexual victimization stems from the USE itself, from the woman's self-definition as a victim, or from both. The best-fitting model indicates that labeling is irrelevant to the determination of negative outcomes and that it is the USE itself that is associated with psychological and school-related distress. These results suggest that labeling cannot be considered a valid criterion for determining who has experienced sexual victimization.

Anxiety↗