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Sample records for aging semantic differential

  1. The Aging Semantic Differential in Mandarin Chinese: Measuring Attitudes toward Older Adults in China.

    PubMed

    Gonzales, Ernest; Marchiondo, Lisa A; Tan, Jing; Wang, Yi; Chen, Huajuan

    2017-02-16

    The Aging Semantic Differential (ASD) is the most widely used instrument to measure young people's attitudes towards older adults. This study translated the ASD to Mandarin and examined its psychometric properties. The Mandarin-ASD contains three latent factors (Personality and Mental Health, Societal Participation, and Physical) that have high internal reliability and reasonable discriminate validity. Social work researchers, practitioners and allied professionals may utilize the ASD-Mandarin instrument to measure young people's attitudes towards older adults in China. We issue a call for a universal-ASD that can be applied across different cultural contexts.

  2. Semantic Differential as One of the Research Tools Suitable for Establishing the Attitudes of Pupils to Old Age and Seniors

    ERIC Educational Resources Information Center

    Divilová, Sona

    2016-01-01

    The paper presents the results of the pre-research conducted under the project entitled "Seniors in the Eyes of Children". The main objective of the project was to create and test a research tool in order to establish what the attitudes of pupils to old age and seniors were. Semantic differential was chosen for these purposes. Semantic…

  3. Environmental Attitudes Semantic Differential.

    ERIC Educational Resources Information Center

    Mehne, Paul R.; Goulard, Cary J.

    This booklet is an evaluation instrument which utilizes semantic differential data to assess environmental attitudes. Twelve concepts are included: regulated access to beaches, urban planning, dune vegetation, wetlands, future cities, reclaiming wetlands for building development, city parks, commercial development of beaches, existing cities,…

  4. Aging and Semantic Activation.

    ERIC Educational Resources Information Center

    Howard, Darlene V.

    Three studies tested the theory that long term memory consists of a semantically organized network of concept nodes interconnected by leveled associations or relations, and that when a stimulus is processed, the corresponding concept node is assumed to be temporarily activated and this activation spreads to nearby semantically related nodes. In…

  5. Differentiating Sense through Semantic Interaction Data

    PubMed Central

    Elizabeth Workman, T.; Weir, Charlene; Rindflesch, Thomas C.

    2016-01-01

    Words which have different representations but are semantically related, such as dementia and delirium, can pose difficult issues in understanding text. We explore the use of interaction frequency data between semantic elements as a means to differentiate concept pairs, using semantic predications extracted from the biomedical literature. We applied datasets of features drawn from semantic predications for semantically related pairs to two Expectation Maximization clustering processes (without, and with concept labels), then used all data to train and evaluate several concept classifying algorithms. For the unlabeled datasets, 80% displayed expected cluster count and similar or matching proportions; all labeled data exhibited similar or matching proportions when restricting cluster count to unique labels. The highest performing classifier achieved 89% accuracy, with F1 scores for individual concept classification ranging from 0.69 to 1. We conclude with a discussion on how these findings may be applied to natural language processing of clinical text. PMID:28269921

  6. Sampling Adequacy and the Semantic Differential.

    ERIC Educational Resources Information Center

    Dziuban, Charles D.; Shirkey, Edwin C.

    The Kaiser Measures of Sampling Adequacy (MSA) were derived for a typical six-concept Semantic Differential. The overall indices indicated that both concept and total correlation matrices would lead to comparable decisions regarding the psychometric quality of the sample data sets. The individual MSA's, however, revealed considerable variability…

  7. A Revised Semantic Differential Scale Distinguishing between Negative and Positive God Images

    ERIC Educational Resources Information Center

    Francis, Leslie J.; Robbins, Mandy; Gibson, Harry M.

    2006-01-01

    A sample of 755 school pupils between the ages of 11 and 18 years completed the Benson and Spilka semantic differential measure of God images. Factor analysis indicated the advantages of re-scoring the measure as an eight item unidimensional index, defining semantic space relating to God images ranging from negative affect to positive affect.…

  8. Computer Programs for the Semantic Differential: Further Modifications.

    ERIC Educational Resources Information Center

    Lawson, Edwin D.; And Others

    The original nine programs for semantic differential analysis have been condensed into three programs which have been further refined and augmented. They yield: (1) means, standard deviations, and standard errors for each subscale on each concept; (2) Evaluation, Potency, and Activity (EPA) means, standard deviations, and standard errors; (3)…

  9. Effects of Age on Cognitive Control during Semantic Categorization

    PubMed Central

    Mudar, Raksha A.; Chiang, Hsueh-Sheng; Maguire, Mandy J.; Spence, Jeffrey S.; Eroh, Justin; Michael, A. Kraut; Hart, John

    2015-01-01

    We used event-related potentials (ERPs) to study age effects of perceptual (basic-level) vs. perceptual-semantic (superordinate-level) categorization on cognitive control using the go/nogo paradigm. Twenty-two younger (11 M; 21±2.2 years) and 22 older adults (9 M; 63±5.8 years) completed two visual go/nogo tasks. In the single car task (SiC) (basic), go/nogo responses were made based on single exemplars of a car (go) and a dog (nogo). In the object animal task (ObA) (superordinate), responses were based on multiple exemplars of objects (go) and animals (nogo). Each task consisted of 200 trials: 160 (80%) ‘go’ trials that required a response through button pressing and 40 (20%) ‘nogo’ trials that required inhibition/withholding of a response. ERP data revealed significantly reduced nogo-N2 and nogo-P3 amplitudes in older compared to younger adults, whereas go-N2 and go-P3 amplitudes were comparable in both groups during both categorization tasks. Although the effects of categorization levels on behavioral data and P3 measures were similar in both groups with longer response times, lower accuracy scores, longer P3 latencies, and lower P3 amplitudes in ObA compared to SiC, N2 latency revealed age group differences moderated by the task. Older adults had longer N2 latency for ObA compared to SiC, in contrast, younger adults showed no N2 latency difference between SiC and ObA. Overall, these findings suggest that age differentially affects neural processing related to cognitive control during semantic categorization. Furthermore, in older adults, unlike in younger adults, levels of categorization modulate neural processing related to cognitive control even at the early stages (N2). PMID:25823764

  10. Semantic Richness and Aging: The Effect of Number of Features in the Lexical Decision Task

    ERIC Educational Resources Information Center

    Robert, Christelle; Rico Duarte, Liliana

    2016-01-01

    The aim of this study was to examine whether the effect of semantic richness in visual word recognition (i.e., words with a rich semantic representation are faster to recognize than words with a poorer semantic representation), is changed with aging. Semantic richness was investigated by manipulating the number of features of words (NOF), i.e.,…

  11. Developing a semantic web model for medical differential diagnosis recommendation.

    PubMed

    Mohammed, Osama; Benlamri, Rachid

    2014-10-01

    In this paper we describe a novel model for differential diagnosis designed to make recommendations by utilizing semantic web technologies. The model is a response to a number of requirements, ranging from incorporating essential clinical diagnostic semantics to the integration of data mining for the process of identifying candidate diseases that best explain a set of clinical features. We introduce two major components, which we find essential to the construction of an integral differential diagnosis recommendation model: the evidence-based recommender component and the proximity-based recommender component. Both approaches are driven by disease diagnosis ontologies designed specifically to enable the process of generating diagnostic recommendations. These ontologies are the disease symptom ontology and the patient ontology. The evidence-based diagnosis process develops dynamic rules based on standardized clinical pathways. The proximity-based component employs data mining to provide clinicians with diagnosis predictions, as well as generates new diagnosis rules from provided training datasets. This article describes the integration between these two components along with the developed diagnosis ontologies to form a novel medical differential diagnosis recommendation model. This article also provides test cases from the implementation of the overall model, which shows quite promising diagnostic recommendation results.

  12. A Comparison of Reliabilities of Graphic and Semantic Differential Factors among Sixth Grade Pupils.

    ERIC Educational Resources Information Center

    Pierson, Ellery M.

    It was wished to determine the relative reliabilities of graphic and semantic differential factors to evaluate applicability of two rival models to the measurement of pupil attitudes. Data was collected from a sample of sixth grade pupils on both abstract graphic and typical semantic differential scales. Reliability estimates were constructed from…

  13. An Examination of Methodological Issues Relevant to the Use and Interpretation of the Semantic Differential.

    ERIC Educational Resources Information Center

    And Others; Mann, Irene T.

    1979-01-01

    Several methodological problems (particularly the assumed bipolarity of scales, instructions regarding use of the midpoint, and concept-scale interaction) which may contribute to a lack of precision in the semantic differential technique were investigated. Results generally supported the use of the semantic differential. (Author/JKS)

  14. Age-related vulnerability in the neural systems supporting semantic processing.

    PubMed

    Peelle, Jonathan E; Chandrasekaran, Keerthi; Powers, John; Smith, Edward E; Grossman, Murray

    2013-01-01

    Our ability to form abstract representations of objects in semantic memory is crucial to language and thought. The utility of this information relies both on the representations of sensory-motor feature knowledge stored in long-term memory and the executive processes required to retrieve, manipulate, and evaluate this semantic knowledge in a task-relevant manner. These complementary components of semantic memory can be differentially impacted by aging. We investigated semantic processing in normal aging using functional magnetic resonance imaging (fMRI). Young and older adults were asked to judge whether two printed object names match on a particular feature (for example, whether a tomato and strawberry have the same color). The task thus required both retrieval of relevant visual feature knowledge of object concepts and evaluating this information. Objects were drawn from either natural kinds or manufactured objects, and were queried on either color or shape in a factorial design. Behaviorally, all subjects performed well, but older adults could be divided into those whose performance matched that of young adults (better performers) and those whose performance was worse (poorer performers). All subjects activated several cortical regions while performing this task, including bilateral inferior and lateral temporal cortex and left frontal and prefrontal cortex. Better performing older adults showed increased overall activity in bilateral premotor cortex and left lateral occipital cortex compared to young adults, and increased activity in these brain regions relative to poorer performing older adults who also showed gray matter atrophy in premotor cortex. These findings highlight the contribution of domain-general executive processing brain regions to semantic memory, and illustrate differences in how these regions are recruited in healthy older adults.

  15. Three-Mode Models and Individual Differences in Semantic Differential Data.

    ERIC Educational Resources Information Center

    Murakami, Takashi; Kroonenberg, Pieter M.

    2003-01-01

    Demonstrated how individual differences in semantic differential data can be modeled and assessed using three-mode models by studying the characterization of Chopin's "Preludes" by 38 Japanese college students. (SLD)

  16. Neural changes associated with semantic processing in healthy aging despite intact behavioral performance.

    PubMed

    Lacombe, Jacinthe; Jolicoeur, Pierre; Grimault, Stephan; Pineault, Jessica; Joubert, Sven

    2015-10-01

    Semantic memory recruits an extensive neural network including the left inferior prefrontal cortex (IPC) and the left temporoparietal region, which are involved in semantic control processes, as well as the anterior temporal lobe region (ATL) which is considered to be involved in processing semantic information at a central level. However, little is known about the underlying neuronal integrity of the semantic network in normal aging. Young and older healthy adults carried out a semantic judgment task while their cortical activity was recorded using magnetoencephalography (MEG). Despite equivalent behavioral performance, young adults activated the left IPC to a greater extent than older adults, while the latter group recruited the temporoparietal region bilaterally and the left ATL to a greater extent than younger adults. Results indicate that significant neuronal changes occur in normal aging, mainly in regions underlying semantic control processes, despite an apparent stability in performance at the behavioral level.

  17. Age of Bilingual Exposure Is Related to the Contribution of Phonological and Semantic Knowledge to Successful Reading Development.

    PubMed

    Jasińska, Kaja K; Petitto, Laura-Ann

    2017-02-07

    Bilingual children's reading as a function of age of first bilingual language exposure (AoE) was examined. Bilingual (varied AoE) and monolingual children (N = 421) were compared in their English language and reading abilities (6-10 years) using phonological awareness, semantic knowledge, and reading tasks. Structural equation modeling was applied to determine how bilingual AoE predicts reading outcomes. Early exposed bilinguals outperformed monolinguals on phonological awareness and word reading. Phonology and semantic (vocabulary) knowledge differentially predicted reading depending on the bilingual experience and AoE. Understanding how bilingual experiences impact phonological awareness and semantic knowledge, and in turn, impact reading outcomes is relevant for our understanding of what language and reading skills are best to focus on, and when, to promote optimal reading success.

  18. The cumulative semantic interference effect in normal and pathological ageing.

    PubMed

    Mulatti, Claudio; Calia, Clara; De Caro, Maria Fara; Della Sala, Sergio

    2014-12-01

    People affected by mild cognitive impairment (MCI), a precursor of Alzheimer's Disease, present with impairments in picture naming, a lexical/semantic task which rests on the activation of perceptual, semantic, and phonological representations. The poor performance of MCI individuals in picture naming has been accounted for in terms of deficits of either the perceptual, semantic, or phonological stages. To disentangle the source of this deficit we compared the cumulative semantic interference effect (Howard et al., 2006. Cognition. 100, 464-482.) and the repetition priming effect of a group of people with MCI to that of a group of healthy elderly participants and with a group of healthy young participants. The cumulative semantic interference effect defines a linear increase in the picture naming reaction times which is function of the already named pictures belonging to the same semantic category to which the named picture belongs. The repetition priming effect refers to an increase in performance for repeated items compared to unrepeated items. Results showed that whereas the cumulative semantic interference effect was present in the healthy elderly and young samples, it was absent in the MCI sample; instead, all groups showed comparable repetition priming effects. This pattern of results suggests that the impairment in picture naming exhibited by MCI individuals is due to an inefficient semantic access.

  19. Differential pattern of semantic memory organization between bipolar I and II disorders.

    PubMed

    Chang, Jae Seung; Choi, Sungwon; Ha, Kyooseob; Ha, Tae Hyon; Cho, Hyun Sang; Choi, Jung Eun; Cha, Boseok; Moon, Eunsoo

    2011-06-01

    Semantic cognition is one of the key factors in psychosocial functioning. The aim of this study was to explore the differences in pattern of semantic memory organization between euthymic patients with bipolar I and II disorders using the category fluency task. Study participants included 23 euthymic subjects with bipolar I disorder, 23 matched euthymic subjects with bipolar II disorder and 23 matched control subjects. All participants were assessed for verbal learning, recall, learning strategies, and fluency. The combined methods of hierarchical clustering and multidimensional scaling were used to compare the pattern of semantic memory organization among the three groups. Quantitative measures of verbal learning, recall, learning strategies, and fluency did not differ between the three groups. A two-cluster structure of semantic memory organization was identified for the three groups. Semantic structure was more disorganized in the bipolar I disorder group compared to the bipolar II disorder. In addition, patients with bipolar II disorder used less elaborate strategies of semantic memory organization than those of controls. Compared to healthy controls, strategies for categorization in semantic memory appear to be less knowledge-based in patients with bipolar disorders. A differential pattern of semantic memory organization between bipolar I and II disorders indicates a higher risk of cognitive abnormalities in patients with bipolar I disorder compared to patients with bipolar II disorder. Exploring qualitative nature of neuropsychological domains may provide an explanatory insight into the characteristic behaviors of patients with bipolar disorders.

  20. Semantic Richness and Aging: The Effect of Number of Features in the Lexical Decision Task.

    PubMed

    Robert, Christelle; Rico Duarte, Liliana

    2016-04-01

    The aim of this study was to examine whether the effect of semantic richness in visual word recognition (i.e., words with a rich semantic representation are faster to recognize than words with a poorer semantic representation), is changed with aging. Semantic richness was investigated by manipulating the number of features of words (NOF), i.e., the number of characteristics that describe the meaning of words. Half of the words had a high NOF and the other half had a low NOF. Young adults (19.6 years) and older adults (66.3 years) performed a lexical decision task. An interaction was found between age group and NOF on word latencies. More precisely, a facilitatory effect of NOF was observed for the young adults, but not for the older ones. These data are consistent with the assumption of an age-related decline in feedback activation from semantics to orthography.

  1. German norms for semantic typicality, age of acquisition, and concept familiarity.

    PubMed

    Schröder, Astrid; Gemballa, Teresa; Ruppin, Steffie; Wartenburger, Isabell

    2012-06-01

    The present study introduces the first substantial German database with norms for semantic typicality, age of acquisition, and concept familiarity for 824 exemplars of 11 semantic categories, including four natural (ANIMALS, BIRDS, FRUITS,: and VEGETABLES: ) and five man-made (CLOTHING, FURNITURE, VEHICLES, TOOLS: , and MUSICAL INSTRUMENTS: ) categories, as well as PROFESSIONS: and SPORTS: . Each category exemplar in the database was collected empirically in an exemplar generation study. For each category exemplar, norms for semantic typicality, estimated age of acquisition, and concept familiarity were gathered in three different rating studies. Reliability data and additional analyses on effects of semantic category and intercorrelations between age of acquisition, semantic typicality, concept familiarity, word length, and word frequency are provided. Overall, the data show high inter- and intrastudy reliabilities, providing a new resource tool for designing experiments with German word materials. The full database is available in the supplementary material of this file and also at www.psychonomic.org/archive .

  2. Differentiation of perceptual and semantic subsequent memory effects using an orthographic paradigm.

    PubMed

    Kuo, Michael C C; Liu, Karen P Y; Ting, Kin Hung; Chan, Chetwyn C H

    2012-11-27

    This study aimed to differentiate perceptual and semantic encoding processes using subsequent memory effects (SMEs) elicited by the recognition of orthographs of single Chinese characters. Participants studied a series of Chinese characters perceptually (by inspecting orthographic components) or semantically (by determining the object making sounds), and then made studied or unstudied judgments during the recognition phase. Recognition performance in terms of d-prime measure in the semantic condition was higher, though not significant, than that of the perceptual condition. The between perceptual-semantic condition differences in SMEs at P550 and late positive component latencies (700-1000ms) were not significant in the frontal area. An additional analysis identified larger SME in the semantic condition during 600-1000ms in the frontal pole regions. These results indicate that coordination and incorporation of orthographic information into mental representation is essential to both task conditions. The differentiation was also revealed in earlier SMEs (perceptual>semantic) at N3 (240-360ms) latency, which is a novel finding. The left-distributed N3 was interpreted as more efficient processing of meaning with semantically learned characters. Frontal pole SMEs indicated strategic processing by executive functions, which would further enhance memory.

  3. The Semantic Web: Differentiating between Taxonomies and Ontologies.

    ERIC Educational Resources Information Center

    Adams, Katherine

    2002-01-01

    Explains the concept of a semantic Web where software agents perform jobs for end-users by using hierarchies, metadata, and structured vocabularies. Discusses taxonomies; defining ontologies and taxonomies; standardized language and conceptual relationships; different points of emphasis; and topic maps as new Web infrastructure. (LRW)

  4. The Semantic Network at Work and Rest: Differential Connectivity of Anterior Temporal Lobe Subregions

    PubMed Central

    Jackson, Rebecca L.; Hoffman, Paul; Pobric, Gorana

    2016-01-01

    The anterior temporal lobe (ATL) makes a critical contribution to semantic cognition. However, the functional connectivity of the ATL and the functional network underlying semantic cognition has not been elucidated. In addition, subregions of the ATL have distinct functional properties and thus the potential differential connectivity between these subregions requires investigation. We explored these aims using both resting-state and active semantic task data in humans in combination with a dual-echo gradient echo planar imaging (EPI) paradigm designed to ensure signal throughout the ATL. In the resting-state analysis, the ventral ATL (vATL) and anterior middle temporal gyrus (MTG) were shown to connect to areas responsible for multimodal semantic cognition, including bilateral ATL, inferior frontal gyrus, medial prefrontal cortex, angular gyrus, posterior MTG, and medial temporal lobes. In contrast, the anterior superior temporal gyrus (STG)/superior temporal sulcus was connected to a distinct set of auditory and language-related areas, including bilateral STG, precentral and postcentral gyri, supplementary motor area, supramarginal gyrus, posterior temporal cortex, and inferior and middle frontal gyri. Complementary analyses of functional connectivity during an active semantic task were performed using a psychophysiological interaction (PPI) analysis. The PPI analysis highlighted the same semantic regions suggesting a core semantic network active during rest and task states. This supports the necessity for semantic cognition in internal processes occurring during rest. The PPI analysis showed additional connectivity of the vATL to regions of occipital and frontal cortex. These areas strongly overlap with regions found to be sensitive to executively demanding, controlled semantic processing. SIGNIFICANCE STATEMENT Previous studies have shown that semantic cognition depends on subregions of the anterior temporal lobe (ATL). However, the network of regions

  5. Upper limb movement differentiation according to taxonomic semantic category.

    PubMed

    Bennett, K M; Thomas, J I; Jervis, C; Castiello, U

    1998-01-26

    The size or shape of an object, its perceptual features, determine the patterning of an arm and hand action involving that object. Little is known about the role played by the taxonomic semantic attributes of an object for perceptuomotor processing. In this study we investigated whether the semantic relationship between two target stimuli influences the kinematics of a bilateral reach-to-grasp action. The results showed that reach-to-grasp movements preceding the action of putting living-thing pairs together were faster, and showed earlier settings of reach and grasp temporal parameters, than movements involving pairs of non-living things. It is hypothesized that this reflects the recruitment of different categorical perceptuomotor pathways.

  6. Combining a semantic differential with fMRI to investigate brands as cultural symbols.

    PubMed

    Schaefer, Michael; Rotte, Michael

    2010-06-01

    Traditionally, complex cultural symbols like brands are investigated with psychological approaches. Often this is done by using semantic differentials, in which participants are asked to rate a brand regarding different pairs of adjectives. Only recently, functional magnetic resonance imaging (fMRI) has been used to examine brands. In the current work we used fMRI in combination with a semantic differential to cross-validate both methods and to improve the characterization of the basic factors constituting the semantic space. To this end we presented pictures of brands while recording subject's brain activity during an fMRI experiment. Results of the semantic differential arranged the brands in a semantic space illustrating their relationships to other cultural symbols. FMRI results revealed activation of the medial prefrontal cortex for brands that loaded high on the factor 'social competence', suggesting an involvement of a cortical network associated with social cognitions. In contrast, brands closely related to the factor 'potency' showed decreased activity in the superior frontal gyri, possibly related to working memory during task performance. We discuss the results as a different engagement of the prefrontal cortex when perceiving brands as cultural symbols.

  7. Adult aging effects on semantic and episodic priming in word recognition.

    PubMed

    Laver, Gary D

    2009-03-01

    Two experiments compared automatic semantic and episodic priming effects in adult aging. In the 1st experiment, target words were semantically primed; in the 2nd experiment, targets were primed by repetition of semantically unrelated words. Both experiments involved a pronunciation task with response signals at fixed times following target onset. Consequently, priming was measured as improvement in the percentage of correct responses. Priming was also calculated with speed-accuracy measures of intercept and slope. Both types of priming effect were significant in the percentage correct and slope measures, but no age group differences were found. Furthermore, the magnitudes of the priming effects were equivalent. The age-resistant nature of semantic and episodic priming, as well as evidence for a common theoretical mechanism, is discussed.

  8. Social Concepts and Judgments: A Semantic Differential Analysis of the Concepts Feminist, Man, and Woman

    ERIC Educational Resources Information Center

    Pierce, W. David; Sydie, R. A.; Stratkotter, Rainer

    2003-01-01

    Male and female participants (N = 274) made judgments about the social concepts of "feminist," "man," and "woman" on 63 semantic differential items. Factor analysis identified three basic dimensions termed evaluative, potency, and activity as well as two secondary factors called expressiveness and sexuality. Results for the evaluative dimension…

  9. The Case for the Semantic Differential in Organizational and Business Research

    ERIC Educational Resources Information Center

    Piotrowski, Chris; Guyette, Roger W., Jr.

    2010-01-01

    Attitude measurement has been and continues to be a central component in the field of social psychology. The semantic differential technique has proven to be a well-respected measuring device of attitudes since the 1960s, particularly in the social sciences. Given the importance of attitudes in the business world with reference to preferences in…

  10. Development and Application of a New Approach to Testing the Bipolarity of Semantic Differential Items.

    ERIC Educational Resources Information Center

    Cogliser, Claudia C.; Schriesheim, Chester A.

    1994-01-01

    A method of testing semantic differential scales for bipolarity is developed using a new conception of bipolarity that does not require unidimensionality. Assessment of Fielder's Least Preferred Coworker instrument with 63 college student subjects using multidimensional scaling revealed its significant departures from bipolarity. (SLD)

  11. An Easy Semantic Differential Technique: Construction of a Three-Dimensional Model.

    ERIC Educational Resources Information Center

    Lawson, E. D.

    Osgood, Suci, and Tannenbaum in their work with the semantic differential developed a technique with which data from an individual could be represented by a three-dimensional model. The model is derived from distance scores based upon profile ratings of concepts such as mother or self, on subscales such as kind-cruel, weak-strong, etc. Osgood…

  12. Knowledge networks in the age of the Semantic Web.

    PubMed

    Neumann, Eric; Prusak, Larry

    2007-05-01

    The Web has become the major medium for various communities to share their knowledge. To this end, it provides an optimal environment for knowledge networks. The web offers global connectivity that is virtually instantaneous, and whose resources and documents can easily be indexed for easy searching. In the coupled realms of biomedical research and healthcare, this has become especially important where today many thousands of communities already exist that connect across academia, hospitals and industry. These communities also rely on several forms of knowledge assets, including publications, experimental data, domain-specific vocabularies and policies. Web-based communities will be one of the earlier beneficiaries of the emerging Semantic Web. With the new standards and technologies of the Semantic Web, effective utilization of knowledge networks will expand profoundly, fostering new levels of innovation and knowledge.

  13. Informatics in radiology: radiology gamuts ontology: differential diagnosis for the Semantic Web.

    PubMed

    Budovec, Joseph J; Lam, Cesar A; Kahn, Charles E

    2014-01-01

    The Semantic Web is an effort to add semantics, or "meaning," to empower automated searching and processing of Web-based information. The overarching goal of the Semantic Web is to enable users to more easily find, share, and combine information. Critical to this vision are knowledge models called ontologies, which define a set of concepts and formalize the relations between them. Ontologies have been developed to manage and exploit the large and rapidly growing volume of information in biomedical domains. In diagnostic radiology, lists of differential diagnoses of imaging observations, called gamuts, provide an important source of knowledge. The Radiology Gamuts Ontology (RGO) is a formal knowledge model of differential diagnoses in radiology that includes 1674 differential diagnoses, 19,017 terms, and 52,976 links between terms. Its knowledge is used to provide an interactive, freely available online reference of radiology gamuts ( www.gamuts.net ). A Web service allows its content to be discovered and consumed by other information systems. The RGO integrates radiologic knowledge with other biomedical ontologies as part of the Semantic Web.

  14. Differential Involvement of the Anterior Temporal Lobes in Famous People Semantics

    PubMed Central

    Chedid, Georges; Wilson, Maximiliano A.; Provost, Jean-Sebastien; Joubert, Sven; Rouleau, Isabelle; Brambati, Simona M.

    2016-01-01

    The ability to recognize a famous person occurs through semantic memory. Previous neuroimaging studies have shown that the anterior temporal lobes (ATLs) are involved in the recognition of famous people. However, it is still a matter of debate whether the semantic processing of names or pictures of famous people has an impact on the activation of ATLs. The aim of this study was to explore the pattern of activation associated with a semantic processing of famous people based on face and written name stimuli. Fifteen healthy young individuals participated in our fMRI study, in which they were asked to perform a semantic categorization judgment task, based on profession, of visually presented pictures, and names of famous people. Neuroimaging findings showed a common pattern of activation for faces and names mainly involving the inferior frontal regions, the posterior temporal lobe, the visual cortex, and the ATLs. We found that the comparison names vs. pictures lead to significant activation in the anterior superior temporal gyrus. On the other hand, faces vs. names seemed associated with increased activation in the medial ATL. Moreover, our results demonstrated that the functional connectivity network anchored to the medial ATL, compared to the anterior STG, is more connected to the bilateral occipital lobe and fusiform gyrus that are regions implicated in the visual system and visual processing of faces. This study provides critical evidence of the differential involvement of ATL regions in semantics of famous people. PMID:27625630

  15. Effects of Age and Education on the Lexico-Semantic Content of Connected Speech in Adults.

    ERIC Educational Resources Information Center

    Le Dorze, Guylaine; Bedard, Christine

    1998-01-01

    Connected speech of 134 healthy, Canadian French-speaking adults, grouped according to age and education level, was analyzed using an aphasia battery. Results demonstrated that older subjects with less education produced fewer content units and were less efficient in transmitting lexico-semantic information. Effects of age and education level on…

  16. Semantic Development in Spanish-English Bilingual Children: Effects of Age and Language Experience

    ERIC Educational Resources Information Center

    Sheng, Li; Bedore, Lisa M.; Pena, Elizabeth D.; Fiestas, Christine

    2013-01-01

    This study examines semantic development in 60 Spanish-English bilingual children, ages 7 years 3 months to 9 years 11 months, who differed orthogonally in age (younger, older) and language experience (higher English experience [HEE], higher Spanish experience [HSE]). Children produced 3 associations to 12 pairs of translation equivalents. Older…

  17. Can Lexical/Semantic Skills Differentiate Deaf or Hard-of-Hearing Readers and Nonreaders?

    ERIC Educational Resources Information Center

    Yoshinaga-Itano, Christine; And Others

    1996-01-01

    Discusses three studies: (1) the effectiveness of semantic analyses of written narratives of students with hearing losses in determining language ability; (2) written-language characteristics of writers matched by reading abilities alone and matched by reading ability and age; and (3) written-language characteristics of writers with hearing…

  18. Spoken Word Recognition in School-Age Children with SLI: Semantic, Phonological, and Repetition Priming

    ERIC Educational Resources Information Center

    Velez, Melinda; Schwartz, Richard G.

    2010-01-01

    Purpose: The purpose of this study was to contribute to the current understanding of how children with specific language impairment (SLI) organize their mental lexicons. The study examined semantic and phonological priming in children with and without SLI. Method: Thirteen children (7;0-11;3 [years;months]) with SLI and 13 age-matched children…

  19. Age-related effects on perceptual and semantic encoding in memory.

    PubMed

    Kuo, M C C; Liu, K P Y; Ting, K H; Chan, C C H

    2014-03-07

    This study examined the age-related subsequent memory effect (SME) in perceptual and semantic encoding using event-related potentials (ERPs). Seventeen younger adults and 17 older adults studied a series of Chinese characters either perceptually (by inspecting orthographic components) or semantically (by determining whether the depicted object makes sounds). The two tasks had similar levels of difficulty. The participants made studied or unstudied judgments during the recognition phase. Younger adults performed better in both conditions, with significant SMEs detected in the time windows of P2, N3, P550, and late positive component (LPC). In the older group, SMEs were observed in the P2 and N3 latencies in both conditions but were only detected in the P550 in the semantic condition. Between-group analyses showed larger frontal and central SMEs in the younger sample in the LPC latency regardless of encoding type. Aging effect appears to be stronger on influencing perceptual than semantic encoding processes. The effects seem to be associated with a decline in updating and maintaining representations during perceptual encoding. The age-related decline in the encoding function may be due in part to changes in frontal lobe function.

  20. Semantic structure in schizophrenia as assessed by the category fluency test: effect of verbal intelligence and age of onset.

    PubMed

    Sumiyoshi, C; Matsui, M; Sumiyoshi, T; Yamashita, I; Sumiyoshi, S; Kurachi, M

    2001-12-31

    It has been reported that long-term memory function, including the semantic structure of category, is impaired in patients with schizophrenia. The present study was performed to determine: (1) whether the deficit in semantic structure in schizophrenia is independent of cultural backgrounds, and (2) the effect of age of onset and verbal intelligence on the degradation of semantic structure in these patients. Fifty-seven Japanese patients with schizophrenia and 33 normal control subjects entered the study. The semantic structure was derived by Multidimensional Scaling (MDS) analysis based on data from the ANIMAL category fluency test. The semantic structure was compared between: (1) schizophrenic patients as a whole vs. normal control subjects; (2) earlier onset (age of onset <20 years) vs. later-onset groups of patients; and (3) high Vocabulary score (score of the Vocabulary subtest from the WAIS-R>7) vs. low Vocabulary score patient groups. Normal control subjects demonstrated the domestic/size dimension in semantic structure, while no such dimension was obtained in patients with schizophrenia. The subgroup comparisons revealed that the later onset or the high Vocabulary score group maintained a relatively intact semantic structure compared with the earlier onset or the low Vocabulary score group, respectively. These findings suggest that the deficit in semantic structure in patients with schizophrenia is commonly observed irrespective of cultural backgrounds, and that age of onset and the level of verbal intelligence are closely related to severity of degradation of the semantic structure in schizophrenia.

  1. Semantic Development in Spanish-English Bilingual Children: Effects of Age and Language Experience

    PubMed Central

    Sheng, Li; Bedore, Lisa M.; Peña, Elizabeth D.; Fiestas, Christine

    2012-01-01

    This study examines semantic development in 60 Spanish-English bilingual children, ages 7 years 3 months to 9 years 11 months, who differed orthogonally in age (younger, older) and language experience (HEE: higher English experience, HSE: higher Spanish experience). Children produced three associations to 12 pairs of translation equivalents. Older children produced more semantic responses and code-switched more often from Spanish to English than younger children. Within each group, children demonstrated better performance in the more frequently used than the less used language. The HEE children outperformed the HSE children in English and the HSE children outperformed the HEE children in Spanish. These effects of age and language experience are consistent with predictions of the Revised Hierarchical Model of bilingual lexical organization. PMID:23163772

  2. Semantic development in Spanish-English bilingual children: effects of age and language experience.

    PubMed

    Sheng, Li; Bedore, Lisa M; Peña, Elizabeth D; Fiestas, Christine

    2013-01-01

    This study examines semantic development in 60 Spanish-English bilingual children, ages 7 years 3 months to 9 years 11 months, who differed orthogonally in age (younger, older) and language experience (higher English experience [HEE], higher Spanish experience [HSE]). Children produced 3 associations to 12 pairs of translation equivalents. Older children produced more semantic responses and code switched more often from Spanish to English than younger children. Within each group, children demonstrated better performance in the more frequently used than the less used language. The HEE children outperformed the HSE children in English and the HSE children outperformed the HEE children in Spanish. These effects of age and language experience are consistent with predictions of the revised hierarchical model of bilingual lexical organization.

  3. [Artificial intelligence meeting neuropsychology. Semantic memory in normal and pathological aging].

    PubMed

    Aimé, Xavier; Charlet, Jean; Maillet, Didier; Belin, Catherine

    2015-03-01

    Artificial intelligence (IA) is the subject of much research, but also many fantasies. It aims to reproduce human intelligence in its learning capacity, knowledge storage and computation. In 2014, the Defense Advanced Research Projects Agency (DARPA) started the restoring active memory (RAM) program that attempt to develop implantable technology to bridge gaps in the injured brain and restore normal memory function to people with memory loss caused by injury or disease. In another IA's field, computational ontologies (a formal and shared conceptualization) try to model knowledge in order to represent a structured and unambiguous meaning of the concepts of a target domain. The aim of these structures is to ensure a consensual understanding of their meaning and a univariant use (the same concept is used by all to categorize the same individuals). The first representations of knowledge in the AI's domain are largely based on model tests of semantic memory. This one, as a component of long-term memory is the memory of words, ideas, concepts. It is the only declarative memory system that resists so remarkably to the effects of age. In contrast, non-specific cognitive changes may decrease the performance of elderly in various events and instead report difficulties of access to semantic representations that affect the semantics stock itself. Some dementias, like semantic dementia and Alzheimer's disease, are linked to alteration of semantic memory. We propose in this paper, using the computational ontologies model, a formal and relatively thin modeling, in the service of neuropsychology: 1) for the practitioner with decision support systems, 2) for the patient as cognitive prosthesis outsourced, and 3) for the researcher to study semantic memory.

  4. Semantic and Phonological Loop Effects on Verbal Working Memory in Middle-Age Adults with Mental Retardation

    ERIC Educational Resources Information Center

    Kittler, Phyllis; Krinsky-McHale, Sharon J.; Devenny, Darlynne A.

    2004-01-01

    Semantic and phonological loop effects on verbal working memory were examined among middle-age adults with Down syndrome and those with unspecified mental retardation in the context of Baddeley's working memory model. Recall was poorer for phonologically similar, semantically similar, and long words compared to recall of dissimilar short words.…

  5. Aging and memory improvement through semantic clustering: The role of list-presentation format.

    PubMed

    Kuhlmann, Beatrice G; Touron, Dayna R

    2016-11-01

    The present study examined how the presentation format of the study list influences younger and older adults' semantic clustering. Spontaneous clustering did not differ between age groups or between an individual-words (presentation of individual study words in consecution) and a whole-list (presentation of the whole study list at once for the same total duration) presentation format in 132 younger (18-30 years, M = 19.7) and 120 older (60-84 years, M = 69.5) adults. However, after instructions to use semantic clustering (second list) age-related differences in recall magnified, indicating a utilization deficiency, and both age groups achieved higher recall in the whole-list than in the individual-words format. While this whole-list benefit was comparable across age groups, it is notable that older adults were only able to improve their average recall performance after clustering instructions in the whole-list but not in the individual-words format. In both formats, instructed clustering was correlated with processing resources (processing speed and, especially, working memory capacity), particularly in older adults. Spontaneous clustering, however, was not related to processing resources but to metacognitive beliefs about the efficacy and difficulty of semantic clustering, neither of which indicated awareness of the benefits of the whole-list presentation format in either age group. Taken together, the findings demonstrate that presentation format has a nontrivial influence on the utilization of semantic clustering in adults. The analyses further highlight important differences between output-based and list-based clustering measures. (PsycINFO Database Record

  6. The Role of Semantic Diversity in Word Recognition across Aging and Bilingualism

    PubMed Central

    Johns, Brendan T.; Sheppard, Christine L.; Jones, Michael N.; Taler, Vanessa

    2016-01-01

    Frequency effects are pervasive in studies of language, with higher frequency words being recognized faster than lower frequency words. However, the exact nature of frequency effects has recently been questioned, with some studies finding that contextual information provides a better fit to lexical decision and naming data than word frequency (Adelman et al., 2006). Recent work has cemented the importance of these results by demonstrating that a measure of the semantic diversity of the contexts that a word occurs in provides a powerful measure to account for variability in word recognition latency (Johns et al., 2012, 2015; Jones et al., 2012). The goal of the current study is to extend this measure to examine bilingualism and aging, where multiple theories use frequency of occurrence of linguistic constructs as central to accounting for empirical results (Gollan et al., 2008; Ramscar et al., 2014). A lexical decision experiment was conducted with four groups of subjects: younger and older monolinguals and bilinguals. Consistent with past results, a semantic diversity variable accounted for the greatest amount of variance in the latency data. In addition, the pattern of fits of semantic diversity across multiple corpora suggests that bilinguals and older adults are more sensitive to semantic diversity information than younger monolinguals. PMID:27458392

  7. Lexical and semantic age-of-acquisition effects on word naming in Spanish.

    PubMed

    Davies, Robert; Barbón, Analia; Cuetos, Fernando

    2013-02-01

    We report a study of the factors that affect reading in Spanish, a language with a transparent orthography. Our focus was on the influence of lexical semantic knowledge in phonological coding. This effect would be predicted to be minimal in Spanish, according to some accounts of semantic effects in reading. We asked 25 healthy adults to name 2,764 mono- and multisyllabic words. As is typical for psycholinguistics, variables capturing critical word attributes were highly intercorrelated. Therefore, we used principal components analysis (PCA) to derive orthogonalized predictors from raw variables. The PCA distinguished components relating to (1) word frequency, age of acquisition (AoA), and familiarity; (2) word AoA, imageability, and familiarity; (3) word length and orthographic neighborhood size; and (4) bigram type and token frequency. Linear mixed-effects analyses indicated significant effects on reading due to each PCA component. Our observations confirm that oral reading in Spanish proceeds through spelling-sound mappings involving lexical and sublexical units. Importantly, our observations distinguish between the effect of lexical frequency (the impact of the component relating to frequency, AoA, and familiarity) and the effect of semantic knowledge (the impact of the component relating to AoA, imageability, and familiarity). Semantic knowledge influences word naming even when all the words being read have regular spelling-sound mappings.

  8. Semantic Differential Scale Method Can Reveal Multi-Dimensional Aspects of Mind Perception.

    PubMed

    Takahashi, Hideyuki; Ban, Midori; Asada, Minoru

    2016-01-01

    As humans, we tend to perceive minds in both living and non-living entities, such as robots. From a questionnaire developed in a previous mind perception study, authors found that perceived minds could be located on two dimensions "experience" and "agency." This questionnaire allowed the assessment of how we perceive minds of various entities from a multi-dimensional point of view. In this questionnaire, subjects had to evaluate explicit mental capacities of target characters (e.g., capacity to feel hunger). However, we sometimes perceive minds in non-living entities, even though we cannot attribute these evidently biological capacities to the entity. In this study, we performed a large-scale web survey to assess mind perception by using the semantic differential scale method. We revealed that two mind dimensions "emotion" and "intelligence," respectively, corresponded to the two mind dimensions (experience and agency) proposed in a previous mind perception study. We did this without having to ask about specific mental capacities. We believe that the semantic differential scale is a useful method to assess the dimensions of mind perception especially for non-living entities that are hard to be attributed to biological capacities.

  9. Semantic Differential Scale Method Can Reveal Multi-Dimensional Aspects of Mind Perception

    PubMed Central

    Takahashi, Hideyuki; Ban, Midori; Asada, Minoru

    2016-01-01

    As humans, we tend to perceive minds in both living and non-living entities, such as robots. From a questionnaire developed in a previous mind perception study, authors found that perceived minds could be located on two dimensions “experience” and “agency.” This questionnaire allowed the assessment of how we perceive minds of various entities from a multi-dimensional point of view. In this questionnaire, subjects had to evaluate explicit mental capacities of target characters (e.g., capacity to feel hunger). However, we sometimes perceive minds in non-living entities, even though we cannot attribute these evidently biological capacities to the entity. In this study, we performed a large-scale web survey to assess mind perception by using the semantic differential scale method. We revealed that two mind dimensions “emotion” and “intelligence,” respectively, corresponded to the two mind dimensions (experience and agency) proposed in a previous mind perception study. We did this without having to ask about specific mental capacities. We believe that the semantic differential scale is a useful method to assess the dimensions of mind perception especially for non-living entities that are hard to be attributed to biological capacities. PMID:27853445

  10. Effects of aging on value-directed modulation of semantic network activity during verbal learning

    PubMed Central

    Cohen, Michael S.; Rissman, Jesse; Suthana, Nanthia A.; Castel, Alan D.; Knowlton, Barbara J.

    2015-01-01

    While impairments in memory recall are apparent in aging, older adults show a remarkably preserved ability to selectively remember information deemed valuable. Here, we use fMRI to compare brain activation in healthy older and younger adults during encoding of high and low value words to determine whether there are differences in how older adults achieve value-directed memory selectivity. We find that memory selectivity in older adults is associated with value-related changes in activation during word presentation in left hemisphere regions that are involved in semantic processing, similar to young adults. However, highly selective young adults show a relatively greater increase in semantic network activity during encoding of high-value items, whereas highly selective older adults show relatively diminished activity during encoding of low-value items. Additionally, only younger adults showed value-related increases in activity in semantic and reward processing regions during presentation of the value cue preceding each to-be-remembered word. Young adults therefore respond to cue value more proactively than do older adults, yet the magnitude of value-related differences in cue period brain activity did not predict individual differences in memory selectivity. Thus, our data also show that age-related reductions in prestimulus activity do not always lead to inefficient performance. PMID:26244278

  11. Effects of age and school type on unconstrained, phonemic, and semantic verbal fluency in children.

    PubMed

    Jacobsen, Geise Machado; Prando, Mirella Liberatore; Moraes, André Luiz; Pureza, Janice da Rosa; Gonçalves, Hosana Alves; Siqueira, Larissa de Souza; Joanette, Yves; Fonseca, Rochele Paz

    2017-01-01

    Biological and cultural factors have been found to have a significant influence on cognitive development and performance in neuropsychological instruments such as verbal fluency tasks (VFT). Variations of traditional VFT, involving unconstrained word production and increased retrieval times, may provide further data regarding the executive, attentional, mnemonic, and linguistic abilities involved in VFT. As such, the aim of this study was to investigate the impact of age and school type on the performance of 6- to 12-year-old children in unconstrained, phonemic, and semantic VFT. The VFT were administered to 460 participants. The effects of age and school type on verbal fluency (VF) performance were analyzed using a two-way analysis of variance, followed by Bonferroni post-hoc tests (p ≤ .05). A repeated-measures analysis was also used to evaluate VF performance over time (p ≤ .05). Main effects of age and school type were identified on all measures (effect sizes ranged from .05 to .32, p ≤ .05). VF scores increased with age and were higher among private school students. The influence of age on VFT may be associated with the development of executive functions. The impact of type of school on VF performance may be explained by the greater availability of cognitive stimulation (semantic knowledge) provided by private schools and families with better socioeconomic levels.

  12. Generation Y, wine and alcohol. A semantic differential approach to consumption analysis in Tuscany.

    PubMed

    Marinelli, Nicola; Fabbrizzi, Sara; Alampi Sottini, Veronica; Sacchelli, Sandro; Bernetti, Iacopo; Menghini, Silvio

    2014-04-01

    The aim of the study is the elicitation of the consumer's semantic perception of different alcoholic beverages in order to provide information for the definition of communication strategies for both the private sector (and specifically the wine industry) and the public decision maker. Such information can be seen as the basis of a wider social marketing construct aimed at the promotion of responsible drinking among young consumers. The semantic differential approach was used in this study. The data collection was based on a survey to 430 consumers between 18 and 35years old in Tuscany, Italy. The database was organized in a three-way structure, indexing the data in a multiway matrix. The data were processed using a Multiple Factor Analysis (MFA). Moreover, homogeneous clusters of consumers were identified using a Hierarchical Clustering on Principal Components (HCPC) approach. The results of the study highlight that beer and spirits are mainly perceived as "Young", "Social", "Euphoric", "Happy", "Appealing" and "Trendy" beverages, while wine is associated mostly with terms such as "Pleasure", "Quality" and "Comfortable". Furthermore, the cluster analysis allowed for the identification of three groups of individuals with different approaches to alcohol drinking. The results of the study supply a useful information framework for the elaboration of specific communication strategies that, based on the drinking habits of young consumers and their perception of different beverages, can use a language that is very close to the consumer typologies. Such information can be helpful for both private and public communication strategies.

  13. A Diffusion Model Analysis of Adult Age Differences in Episodic and Semantic Long-Term Memory Retrieval

    ERIC Educational Resources Information Center

    Spaniol, Julia; Madden, David J.; Voss, Andreas

    2006-01-01

    Two experiments investigated adult age differences in episodic and semantic long-term memory tasks, as a test of the hypothesis of specific age-related decline in context memory. Older adults were slower and exhibited lower episodic accuracy than younger adults. Fits of the diffusion model (R. Ratcliff, 1978) revealed age-related increases in…

  14. Development of an Appropriate Method for Applying the Semantic Differential to the Measurement of Affective Outcomes of Instruction.

    ERIC Educational Resources Information Center

    Davis, Richard W.

    A method for statistical analysis of semantic differential data in educational evaluation is discussed. Estimated scores for unobserved affective variables are obtained using the canonical factor regression method. This method overcomes previous prolems of bias and inefficiency in computing composite affective indices. In an application of the…

  15. Differential Utilization of Syntactic and Semantic Information by Skilled and Less Skilled Readers in the Intermediate Grades.

    ERIC Educational Resources Information Center

    Willows, Dale M.; Ryan, Ellen Bouchard

    1981-01-01

    Matched pairs of skilled and less skilled readers read aloud material in cloze procedure format and printed in geometric transformations. Skilled readers made greater use of grammatical and contextual information. The stability of differences suggests that differential utilization of syntactic and semantic cues contributes to differences in…

  16. The Relationship Between Responses to Science Concepts on a Semantic Differential Instrument and Achievement in Freshman Physics and Chemistry.

    ERIC Educational Resources Information Center

    Rothman, Arthur Israel

    Students taking freshman physics and freshman chemistry at The State University of New York at Buffalo (SUNYAB) were administered a science-related semantic differential instrument. This same test was administered to physics and chemistry graduate students from SUNYAB and the University of Rochester. A scoring procedure was developed which…

  17. Differential Resting State Connectivity Patterns and Impaired Semantically Cued List Learning Test Performance in Early Course Remitted MDD

    PubMed Central

    Rao, Julia A.; Jenkins, Lisanne M.; Hymen, Erica; Feigon, Maia; Weisenbach, Sara L.; Zubieta, Jon-Kar; Langenecker, Scott A.

    2016-01-01

    Objective There is a well-known association between memory impairment and Major Depressive Disorder (MDD). Additionally, recent studies are also showing resting-state (rs) fMRI abnormalities in active and remitted MDD. However, no studies to date have examined both resting state connectivity and memory performance in early course remitted MDD, nor the relationship between connectivity and semantically-cued episodic memory. Method Resting state MRI (rsMRI) data from two 3.0 Tesla GE scanners were collected from 34 unmedicated young adults with remitted MDD (rMDD) and 23 healthy controls (HCs) between 18–23 years of age using bilateral seeds in the hippocampus. Participants also completed a semantically-cued list-learning test and their performance was correlated with hippocampal seed-based rsMRI. Regression models were also used to predict connectivity patterns from memory performance. Results After correcting for sex, rMDD performed worse than HCs on the total number of words recalled and recognized. rMDD demonstrated significant in-network hypoactivation between the hippocampus and multiple fronto-temporal regions, and multiple extra-network hyperconnectivities between the hippocampus and fronto-parietal regions when compared to HCs. Memory performance negatively predicted connectivity in HCs and positively predicted connectivity in rMDD. Conclusions Even when individuals with a history of MDD are no longer displaying active depressive symptoms, they continue to demonstrate worse memory performance, disruptions in hippocampal connectivity, and a differential relationship between episodic memory and hippocampal connectivity. PMID:26888619

  18. Emotion processing in the aging brain is modulated by semantic elaboration.

    PubMed

    Ritchey, Maureen; Bessette-Symons, Brandy; Hayes, Scott M; Cabeza, Roberto

    2011-03-01

    The neural correlates of emotion processing have been shown to vary with age: older adults (OAs) exhibit increased frontal activations and, under some circumstances, decreased amygdala activations relative to young adults (YAs) during emotion processing. Some of these differences are additionally modulated by valence, with age-related biases toward positive versus negative stimuli, and are thought to depend on OAs' capacity for controlled elaboration. However, the role of semantic elaboration in mediating valence effects in the aging brain has not yet been explicitly tested. In the present study, YAs and OAs were scanned while they viewed negative, neutral, and positive pictures during either a deep, elaborative task or a shallow, perceptual task. fMRI results reveal that emotion-related activity in the amygdala is preserved in aging and insensitive to elaboration demands. This study provides novel evidence that differences in valence processing are modulated by elaboration: relative to YAs, OAs show enhanced activity in the medial prefrontal cortex (PFC) and ventrolateral PFC in response to positive versus negative stimuli, but only during elaborative processing. These positive valence effects are predicted by individual differences in executive function in OAs for the deep but not shallow task. Finally, psychophysiological interaction analyses reveal age effects on valence-dependent functional connectivity between medial PFC and ventral striatum, as well as age and task effects on medial PFC-retrosplenial cortex interactions. Altogether, these findings provide support for the hypothesis that valence shifts in the aging brain are mediated by controlled processes such as semantic elaboration, self-referential processing, and emotion regulation.

  19. Determinants of famous name processing speed: age of acquisition versus semantic connectedness.

    PubMed

    Smith-Spark, James H; Moore, Viv; Valentine, Tim

    2013-02-01

    The age of acquisition (AoA) and the amount of biographical information known about celebrities have been independently shown to influence the processing of famous people. In this experiment, we investigated the facilitative contribution of both factors to famous name processing. Twenty-four mature adults participated in a familiarity judgement task, in which the names of famous people were grouped orthogonally by AoA and by the number of bits of biographical information known about them (number of facts known; NoFK). Age of acquisition was found to have a significant effect on both reaction time (RT) and accuracy of response, but NoFK did not. The RT data also revealed a significant AoA×NoFK interaction. The amount of information known about a celebrity played a facilitative role in the processing of late-acquired, but not early-acquired, celebrities. Once AoA is controlled, it would appear that the semantic system ceases to have a significant overall influence on the processing of famous people. The pre-eminence of AoA over semantic connectedness is considered in the light of current theories of AoA and how their influence might interact.

  20. Differential Utilization of Syntactic and Semantic Information by Skilled and Less Skilled Readers in the Intermediate Grades.

    ERIC Educational Resources Information Center

    Ryan, Ellen Bouchard; Willows, Dale M.

    To assess the extent to which syntactic and semantic information guides the reading performance of skilled and less-skilled readers in the intermediate grades, a study was conducted involving 96 fourth, fifth, and sixth grade students. The students were matched both within and across grade level on nonverbal IQ and within each grade level on age.…

  1. Lexico-semantic effects on word naming in Persian: does age of acquisition have an effect?

    PubMed

    Bakhtiar, Mehdi; Weekes, Brendan

    2015-02-01

    The age of acquisition (AoA) of a word has an effect on skilled reading performance. According to the arbitrary-mapping (AM) hypothesis, AoA effects on word naming are a consequence of arbitrary mappings between input and output in the lexical network. The AM hypothesis predicts that effects of AoA will be observed when words have unpredictable orthography-to-phonology (OP) mappings. The Persian writing system is characterized by a degree of consistency between OP mappings, making words transparent. However, the omission of vowels in the script used by skilled readers makes the OP mappings of many words unpredictable or opaque. In this study, we used factor analysis to test which lexico-semantic variables, including AoA, predict the reading aloud of monosyllabic Persian words with different spelling transparencies (transparent or opaque). Linear mixed-effect regression analysis revealed that a Lexical factor (loading on word familiarity, spoken frequency, and written frequency) and a Semantic factor (loading on AoA, imageability, and familiarity) significantly predict word-naming latencies in Persian. Further analysis revealed a significant interaction between AoA and transparency, with larger effects of AoA for opaque than for transparent words and a significant interaction between imageability and AoA on reading opaque words; that is, AoA effects are more pronounced for low-imageability opaque words than for high-imageability opaque words. Interactions between these factors and spelling transparency suggest that late-acquired opaque words receive greater input from the semantic reading route. Implications for understanding the AoA effects on word naming in Persian are discussed.

  2. On the influence of typicality and age of acquisition on semantic processing: Diverging evidence from behavioural and ERP responses.

    PubMed

    Räling, Romy; Holzgrefe-Lang, Julia; Schröder, Astrid; Wartenburger, Isabell

    2015-08-01

    Various behavioural studies show that semantic typicality (TYP) and age of acquisition (AOA) of a specific word influence processing time and accuracy during the performance of lexical-semantic tasks. This study examines the influence of TYP and AOA on semantic processing at behavioural (response times and accuracy data) and electrophysiological levels using an auditory category-member-verification task. Reaction time data reveal independent TYP and AOA effects, while in the accuracy data and the event-related potentials predominantly effects of TYP can be found. The present study thus confirms previous findings and extends evidence found in the visual modality to the auditory modality. A modality-independent influence on semantic word processing is manifested. However, with regard to the influence of AOA, the diverging results raise questions on the origin of AOA effects as well as on the interpretation of offline and online data. Hence, results will be discussed against the background of recent theories on N400 correlates in semantic processing. In addition, an argument in favour of a complementary use of research techniques will be made.

  3. Semantic Integration and Age of Acquisition Effects in Code-Blend Comprehension

    PubMed Central

    Emmorey, Karen

    2016-01-01

    Semantic and lexical decision tasks were used to investigate the mechanisms underlying code-blend facilitation: the finding that hearing bimodal bilinguals comprehend signs in American Sign Language (ASL) and spoken English words more quickly when they are presented together simultaneously than when each is presented alone. More robust facilitation effects were observed for semantic decision than for lexical decision, suggesting that lexical integration of signs and words within a code-blend occurs primarily at the semantic level, rather than at the level of form. Early bilinguals exhibited greater facilitation effects than late bilinguals for English (the dominant language) in the semantic decision task, possibly because early bilinguals are better able to process early visual cues from ASL signs and use these to constrain English word recognition. Comprehension facilitation via semantic integration of words and signs is consistent with co-speech gesture research demonstrating facilitative effects of gesture integration on language comprehension. PMID:26657077

  4. Lexical Processing in School-Age Children with Autism Spectrum Disorder and Children with Specific Language Impairment: The Role of Semantics

    PubMed Central

    Haebig, Eileen; Kaushanskaya, Margarita; Weismer, Susan Ellis

    2016-01-01

    Children with autism spectrum disorder (ASD) and specific language impairment (SLI) often have immature lexical-semantic knowledge; however, the organization of lexical-semantic knowledge is poorly understood. This study examined lexical processing in school-age children with ASD, SLI, and typical development, who were matched on receptive vocabulary. Children completed a lexical decision task, involving words with high and low semantic network sizes and nonwords. Children also completed nonverbal updating and shifting tasks. Children responded more accurately to words from high than from low semantic networks; however, follow-up analyses identified weaker semantic network effects in the SLI group. Additionally, updating and shifting abilities predicted lexical processing, demonstrating similarity in the mechanisms which underlie semantic processing in children with ASD, SLI, and typical development. PMID:26210517

  5. Lexical Processing in School-Age Children with Autism Spectrum Disorder and Children with Specific Language Impairment: The Role of Semantics.

    PubMed

    Haebig, Eileen; Kaushanskaya, Margarita; Ellis Weismer, Susan

    2015-12-01

    Children with autism spectrum disorder (ASD) and specific language impairment (SLI) often have immature lexical-semantic knowledge; however, the organization of lexical-semantic knowledge is poorly understood. This study examined lexical processing in school-age children with ASD, SLI, and typical development, who were matched on receptive vocabulary. Children completed a lexical decision task, involving words with high and low semantic network sizes and nonwords. Children also completed nonverbal updating and shifting tasks. Children responded more accurately to words from high than from low semantic networks; however, follow-up analyses identified weaker semantic network effects in the SLI group. Additionally, updating and shifting abilities predicted lexical processing, demonstrating similarity in the mechanisms which underlie semantic processing in children with ASD, SLI, and typical development.

  6. Lexical Processing in School-Age Children with Autism Spectrum Disorder and Children with Specific Language Impairment: The Role of Semantics

    ERIC Educational Resources Information Center

    Haebig, Eileen; Kaushanskaya, Margarita; Weismer, Susan Ellis

    2015-01-01

    Children with autism spectrum disorder (ASD) and specific language impairment (SLI) often have immature lexical-semantic knowledge; however, the organization of lexical-semantic knowledge is poorly understood. This study examined lexical processing in school-age children with ASD, SLI, and typical development, who were matched on receptive…

  7. Priming Nouns and Verbs: Differential Influences of Semantic and Grammatical Cues in the Two Cerebral Hemispheres

    ERIC Educational Resources Information Center

    Arambel, Stella R.; Chiarello, Christine

    2006-01-01

    The current experiment investigated how sentential form-class expectancies influenced lexical-semantic priming within each hemisphere. Sentences were presented that led readers to expect a noun or a verb and the sentence-final target word was presented to one visual field/hemisphere for a lexical decision response. Noun and verb targets in the…

  8. Development of a Semantic Differential to Assess the Attitude of Secondary School and College Students.

    ERIC Educational Resources Information Center

    Cassel, Russell N.

    The objective of the inquiry was to develop a psychological instrument for use in assessing the attitudes held by secondary school and college students. For reliability purposes, it was deemed that a minimum of 30 or more semantic scales, used as individual items would be essential. A seven position ordinal scale was interposed between each pair…

  9. Differential Prefrontal and Frontotemporal Oxygenation Patterns during Phonemic and Semantic Verbal Fluency

    ERIC Educational Resources Information Center

    Tupak, Sara V.; Badewien, Meike; Dresler, Thomas; Hahn, Tim; Ernst, Lena H.; Herrmann, Martin J.; Fallgatter, Andreas J.; Ehlis, Ann-Christine

    2012-01-01

    Movement artifacts are still considered a problematic issue for imaging research on overt language production. This motion-sensitivity can be overcome by functional near-infrared spectroscopy (fNIRS). In the present study, 50 healthy subjects performed a combined phonemic and semantic overt verbal fluency task while frontal and temporal cortex…

  10. SEMANTICS AND CRITICAL READING.

    ERIC Educational Resources Information Center

    FLANIGAN, MICHAEL C.

    PROFICIENCY IN CRITICAL READING CAN BE ACCELERATED BY MAKING STUDENTS AWARE OF VARIOUS SEMANTIC DEVICES THAT HELP CLARIFY MEANINGS AND PURPOSES. EXCERPTS FROM THE ARTICLE "TEEN-AGE CORRUPTION" FROM THE NINTH-GRADE SEMANTICS UNIT WRITTEN BY THE PROJECT ENGLISH DEMONSTRATION CENTER AT EUCLID, OHIO, ARE USED TO ILLUSTRATE HOW SEMANTICS RELATE TO…

  11. An Exploration of the Effect of Hemodynamic Changes Due to Normal Aging on the fNIRS Response to Semantic Processing of Words

    PubMed Central

    Amiri, Mahnoush; Pouliot, Philippe; Bonnéry, Clément; Leclerc, Paul-Olivier; Desjardins, Michèle; Lesage, Frédéric; Joanette, Yves

    2014-01-01

    Like other neuroimaging techniques assessing cerebral blood oxygenation, near-infrared spectroscopy (NIRS) has been applied in many neurocognitive studies. With NIRS, neural activation can be explored indirectly via hemodynamic changes in the imaged region. In studies of aging, changes in baseline physiology and brain anatomy confound NIRS measures seeking to investigate age-related changes in neuronal activity. The field is thus hampered by the complexity of the aging process itself, and statistical inferences from functional data acquired by optical imaging techniques must be interpreted with care. Multimodal integration of NIRS with both structural and baseline physiological assessments is crucial to avoid misinterpreting neuroimaging signals. In this study, a combination of two different optical techniques, anatomical MRI and Arterial Spin Labeling (ASL), was used to investigate age-related changes in activation during a lexical-semantic processing task. Quantitative analysis revealed decreased baseline oxyhemoglobin and cerebral blood flow in the older adults. Using baseline physiology measures as regressors in the investigation of functional concentration changes when doing analyses of variance, we found significant changes in task-induced areas of activity. In the right hemisphere, more significant age-related activity was observed around the junction of the inferior frontal gyrus and inferior precentral sulcus, along with engagement of Wernicke’s area. In the left hemisphere, the degree and extent of frontal activation, including the dorsolateral prefrontal cortex and inferior frontal gyrus, differed between age groups. Measuring background physiological differences and using their values as regressors in statistical analyses allowed a more appropriate, age-corrected understanding of the functional differentiations between age groups. Age-corrected baselines are thus essential to investigate which components of the NIRS signal are altered by aging. PMID

  12. Age and disability: explaining the wage differential.

    PubMed

    Gannon, Brenda; Munley, Margaret

    2009-07-01

    This paper estimates the level of explained and unexplained factors that contribute to the wage gap between workers with and without disabilities, providing benchmark estimates for Ireland. It separates out the confounding impact of productivity differences between disabled and non-disabled, by comparing wage differentials across three groups, disabled with limitations, disabled without limitations and non-disabled. Furthermore, data are analysed for the years 1995-2001 and two sub-samples pre and post 1998 allow us to decompose wage differentials before and after the Employment Equality Act 1998. Results are comparable to those of the UK and the unexplained component (upper bound of discrimination) is lower once we control for productivity differences. The lower bound level depends on the contribution of unobserved effects and the validity of the selection component in the decomposition model.

  13. Combined Effects of Aging and HIV Infection on Semantic Verbal Fluency: A View of the Cortical Hypothesis Through the Lens of Clustering and Switching

    PubMed Central

    Iudicello, Jennifer E.; Woods, Steven Paul; Deutsch, Reena; Grant, Igor

    2012-01-01

    The profile of HIV-associated neurocognitive disorders (HAND) has classically been characterized as “subcortical”, but questions have arisen as to whether aging with HIV in the antiretroviral therapy era has subtlety shifted the expression of HAND into a more “cortical” disorder (e.g., decay of semantic memory stores). We evaluated this hypothesis by examining semantic fluency and its component processes (i.e., clustering and switching) in 257 individuals across four groups stratified by age (<40 and ≥ 50 years) and HIV serostatus. Jonckheere-Terpstra tests revealed significant monotonic trends for the combined effects of HIV and aging on overall semantic (and letter) fluency and switching, but not cluster size, with greatest deficits evident in the older adults with HIV infection. Within the older HIV-infected cohort, poorer switching was uniquely associated with self-reported declines in instrumental activities of daily living and deficits in learning and executive functions, but not semantic memory. Results suggest that HIV infection and aging may confer adverse additive effects on the executive components of semantic fluency (i.e., switching), rather than a degradation of semantic memory stores (i.e., cluster size), which is a profile that is most consistent with combined frontostriatal neuropathological burden of these two conditions. PMID:22292479

  14. Recall of Details Never Experienced: Effects of Age, Repetition, and Semantic Cues

    ERIC Educational Resources Information Center

    Holliday, Robyn E.; Reyna, Valerie F.; Brainerd, Charles J.

    2008-01-01

    To test theoretical predictions about the role of meaning connections in false memory, the effects of semantic cues and list repetition on children's false memories were evaluated across early childhood to mid-adolescence using the Deese-Roediger-McDermott (DRM) paradigm. True recall and false recall increased from 7 to 13 years. Study list…

  15. Semantic Integration and Age of Acquisition Effects in Code-Blend Comprehension

    ERIC Educational Resources Information Center

    Giezen, Marcel R.; Emmorey, Karen

    2016-01-01

    Semantic and lexical decision tasks were used to investigate the mechanisms underlying code-blend facilitation: the finding that hearing bimodal bilinguals comprehend signs in American Sign Language (ASL) and spoken English words more quickly when they are presented together simultaneously than when each is presented alone. More robust…

  16. Age-Related Differences in Audiovisual Interactions of Semantically Different Stimuli

    ERIC Educational Resources Information Center

    Viggiano, Maria Pia; Giovannelli, Fabio; Giganti, Fiorenza; Rossi, Arianna; Metitieri, Tiziana; Rebai, Mohamed; Guerrini, Renzo; Cincotta, Massimo

    2017-01-01

    Converging results have shown that adults benefit from congruent multisensory stimulation in the identification of complex stimuli, whereas the developmental trajectory of the ability to integrate multisensory inputs in children is less well understood. In this study we explored the effects of audiovisual semantic congruency on identification of…

  17. Semantic Verbal Fluency in Children with and without Autism Spectrum Disorder: Relationship with Chronological Age and IQ

    PubMed Central

    Pastor-Cerezuela, Gemma; Fernández-Andrés, Maria-Inmaculada; Feo-Álvarez, Mireia; González-Sala, Francisco

    2016-01-01

    We administered a semantic verbal fluency (SVF) task to two groups of children (age range from 5 to 8): 47 diagnosed with Autism Spectrum Disorder (ASD Group) and 53 with typical development (Comparison Group), matched on gender, chronological age, and non-verbal IQ. Four specific indexes were calculated from the SVF task, reflecting the different underlying cognitive strategies used: clustering (component of generativity and lexical-semantic access), and switching (executive component, cognitive flexibility). First, we compared the performance of the two groups on the different SVF task indicators, with the ASD group scoring lower than the Comparison Group, although the difference was greater on switching than on clustering. Second, we analyzed the relationships between the different SVF measures and chronological age, verbal IQ and non-verbal IQ. While in the Comparison Group chronological age was the main predictor of performance on the SVF task, in the ASD Group verbal IQ was the best predictor. In the children with ASD, therefore, greater linguistic competence would be associated with better performance on the SVF task, which should be taken into account in speech therapies designed to achieve improvements in linguistic generativity and cognitive flexibility. PMID:27379002

  18. The Equal-Interval Nature of Semantic Differential Scales: An Empirical Investigation Using Fiedler's Least Preferred Coworker (LPC) Scale and Magnitude Estimation and Case III Scaling Procedures.

    ERIC Educational Resources Information Center

    Schriesheim, Chester A.; And Others

    1994-01-01

    Eighteen bipolar adjective pairs that are used in Fielder's Least Preferred (LPC) coworker instrument were examined using 2 scaling techniques with a sample of 113 respondents. Both pair-comparison treatments suggest that true bipolarity does not characterize most of the paired adjectives. Implications for LPC and semantic differential research…

  19. Age-of-acquisition differences in young and older adults affect latencies in lexical decision and semantic categorization.

    PubMed

    De Deyne, Simon; Storms, Gert

    2007-03-01

    An ongoing discussion about the role of age of acquisition (AoA) in word processing concerns the confound with word frequency. This study removed possible frequency confounds by comparing AoA and word familiarity differences in young (18-23 years) and older (52-56 years) adults. A first study investigated the differences in AoA and word familiarity ratings. The norms of AoA and familiarity were significantly different for young and older adults whereas these were previously considered equivalent [Morrison, C. M., Hirsh, K. W., Chappell, T., & Ellis, A. W. (2002). Age and age of acquisition: An evaluation of the cumulative frequency hypothesis. European Journal of Cognitive Psychology, 14, 435-459]. In the second study, AoA and familiarity effects were significantly different for the older and young adults in a lexical decision task. The third study replicated these findings in a semantic artifact/naturally occurring categorization experiment, thus providing further evidence for AoA-effects when word processing requires semantic mediation. Results from both studies were in line with the hypothesis that AoA effects on word processing cannot be accounted for by word frequency or other possible confounds.

  20. [Proposal for a modified method of semantic differential diagnosis in testing for stereotyping of the mentally ill patient].

    PubMed

    Bak, O

    2000-01-01

    In the paper, a proposal of using the semantic differential (by Osgood) for the research on social perception of mentally ill is presented. It allows for investigation of the basic attributes of the stereotype of psychiatric patient: social character, evaluative aspect, simplification, over-generalization of the opinion and its stiffness. The article presents the pilot results coming from the research in a group of students of psychology (first year of studying), who had no lectures in psychiatry by that time (N = 149). The results lead to the conclusion that the picture of mentally ill has social character, that is--some of its attributes are common for a majority of responders (over 77%). They also confirm (with a high certainty--coming to 79%) that most of mentally ill persons (64-80%) are unpredictable, lost, difficult to understand, introvert, unconscious, not self-possessed, excitable, threatening, aggressive and violent. The results show that in the portrait of mentally ill negative attributes are in majority. This portrait--so one-sided and negative--can be one of the basic predictores of social rejection of mentally ill persons.

  1. Age at first marriage in Nepal: differentials and determinants.

    PubMed

    Aryal, Tika Ram

    2007-09-01

    The aim of this paper is to investigate the differentials and determinants of female age at first marriage in rural Nepal. The life table technique was employed to calculate median age at marriage. The proportional hazard model was used to study the effect of various socioeconomic variables, and to identify the magnitude and significance of their effects on the timing of first marriage. The data were taken from a sample survey of Palpa and Rupandehi districts in rural Nepal. Both married and unmarried females of marriageable age were included in the survey. Median age at marriage was about 17 years for data from only married females, whereas it was about 18 years for data from married as well as unmarried females of marriageable age. Median age at marriage was about 16 years for uneducated females and 19 years for females educated up to intermediate or higher level. The analysis underestimates the median age at marriage for married females, probably due to right censoring. The risk of getting married early decreased gradually with increasing year-of-birth cohort. The risk of early marriage was higher among females of high socioeconomic status compared with those of low socioeconomic status. Females engaged in service married earlier than those engaged in household work. High socioeconomic status families are motivated, for religious and prestige reasons, to get their daughters married at an early age, preferably before menarche. Thus, education, occupation and age at menarche are the most powerful factors in deciding the timing of first marriage in Nepal.

  2. Emotional valence and semantic relatedness differentially influence false recognition in mild cognitive impairment, Alzheimer's disease, and healthy elderly.

    PubMed

    Brueckner, Katja; Moritz, Steffen

    2009-03-01

    This study examined whether patients with mild cognitive impairment (MCI) who are at higher risk for later Alzheimer disease (AD) display deficits comparable to patients with diagnosed dementia. We assessed 27 patients with MCI, 36 patients with AD, and 20 healthy older adults with an emotional variant of the Deese-Roediger-McDermott-paradigm. Participants studied four lists that were semantically related to a nonpresented critical theme word. These theme words were either depression-related (i.e., loneliness) or delusion-related (betrayal) or had a positive (holidays) or neutral (window) valence. Despite a normal overall emotional memory and a normal corrected overall false recognition, patients with MCI, as predicted, produced as many false memories as patients with AD. On closer examination, both patient groups showed enhanced false memories to unrelated stimuli and a significant bias to falsely remember stimuli with a positive valence. We conclude that although patients with MCI are not distinguishable from healthy older adults in terms of their overall emotional recognition, positively valenced memories and more specifically false positive memories may represent the signature of a breakdown of emotional memory along the continuum between normal aging and AD.

  3. A database of 629 English compound words: ratings of familiarity, lexeme meaning dominance, semantic transparency, age of acquisition, imageability, and sensory experience.

    PubMed

    Juhasz, Barbara J; Lai, Yun-Hsuan; Woodcock, Michelle L

    2015-12-01

    Since the work of Taft and Forster (1976), a growing literature has examined how English compound words are recognized and organized in the mental lexicon. Much of this research has focused on whether compound words are decomposed during recognition by manipulating the word frequencies of their lexemes. However, many variables may impact morphological processing, including relational semantic variables such as semantic transparency, as well as additional form-related and semantic variables. In the present study, ratings were collected on 629 English compound words for six variables [familiarity, age of acquisition (AoA), semantic transparency, lexeme meaning dominance (LMD), imageability, and sensory experience ratings (SER)]. All of the compound words selected for this study are contained within the English Lexicon Project (Balota et al., 2007), which made it possible to use a regression approach to examine the predictive power of these variables for lexical decision and word naming performance. Analyses indicated that familiarity, AoA, imageability, and SER were all significant predictors of both lexical decision and word naming performance when they were added separately to a model containing the length and frequency of the compounds, as well as the lexeme frequencies. In addition, rated semantic transparency also predicted lexical decision performance. The database of English compound words should be beneficial to word recognition researchers who are interested in selecting items for experiments on compound words, and it will also allow researchers to conduct further analyses using the available data combined with word recognition times included in the English Lexicon Project.

  4. Uveitis in the Aging Eye: Incidence, Patterns, and Differential Diagnosis

    PubMed Central

    Abdulaal, Marwan R.; Abiad, Bachir H.; Hamam, Rola N.

    2015-01-01

    Uveitis is a vision threatening inflammation of the eye that carries considerable morbidity. It is responsible for 10% of legal blindness in the United States and up to 25% in the developing world. Uveitis in patients more than 60 years of age is less common. The aging body has a changing response of the immune system, which might reflect a different pattern of uveitis in the elderly population. In this paper we review the incidence and patterns of uveitis in the elderly as reported in the literature and discuss changes with time. We also delineate a thorough differential diagnosis of de novo uveitis in the elderly. PMID:26090218

  5. Age of Onset of Blindness and the Development of the Semantics of Color Names.

    ERIC Educational Resources Information Center

    Marmor, Gloria Strauss

    The relationship between age of onset of blindness and development of knowledge of color relations was examined with 16 college students who had been born totally blind, 16 who had been blinded totally at approximately 15 years of age, and 16 who had normal vision. Ss were asked to judge the similarities between color names, and judgments were…

  6. Young children's flexible use of semantic cues to word meanings: converging evidence of individual and age differences.

    PubMed

    Deák, Gedeon O; Narasimham, Gayathri

    2014-05-01

    A new test of children's flexible use of semantic cues for word learning extended previous results. In Experiment 1, three- to five-year-olds (N = 51) completed two tests of interpreting several novel words for the same stimulus arrays. Within-sentence phrasal cues implied different stimulus referent properties. Children's cue-using flexibility in the new Flexible Induction of Meanings [Words for Animates] test (FIM-An) was strongly correlated with an established test (Flexible Induction of Meanings [Words for Objects]; Deák, 2000). Individual children showed between-test consistency in using cues to flexibly assign words to different referent properties. There were large individual differences, as well as limited age differences, in the distribution of flexible and inflexible response patterns. The comprehensibility of specific cues, and perceptual salience of specific properties, explained much of the variance. Proportions of flexible and inflexible patterns shifted with age. Experiment 2 replicated these results in N=36 three- and four-year-olds, using a modified FIM-An with more distinctive cues.

  7. Rat hippocampal GABAergic molecular markers are differentially affected by ageing.

    PubMed

    Vela, José; Gutierrez, Antonia; Vitorica, Javier; Ruano, Diego

    2003-04-01

    We previously reported that the pharmacological properties of the hippocampal GABAA receptor and the expression of several subunits are modified during normal ageing. However, correlation between these post-synaptic modifications and pre-synaptic deficits were not determined. To address this issue, we have analysed the mRNA levels of several GABAergic molecular markers in young and old rat hippocampus, including glutamic acid decarboxylase enzymes, parvalbumin, calretinin, somatostatin, neuropeptide Y and vasoactive intestinal peptide (VIP). There was a differential age-related decrease in these interneuronal mRNAs that was inversely correlated with up-regulation of the alpha1 GABA receptor subunit. Somatostatin and neuropeptide Y mRNAs were most frequently affected (75% of the animals), then calretinin and VIP mRNAs (50% of the animals), and parvalbumin mRNA (25% of the animals) in the aged hippocampus. This selective vulnerability was well correlated at the protein/cellular level as analysed by immunocytochemistry. Somatostatin interneurones, which mostly innervate principal cell distal dendrites, were more vulnerable than calretinin interneurones, which target other interneurones. Parvalbumin interneurones, which mostly innervate perisomatic domains of principal cells, were preserved. This age-dependent differential reduction of specific hippocampal inteneuronal subpopulations might produce functional alterations in the GABAergic tone which might be compensated, at the post-synaptic level, by up-regulation of the expression of the alpha1 GABAA receptor subunit.

  8. Differentiation of plant age in grasses using remote sensing

    NASA Astrophysics Data System (ADS)

    Knox, Nichola M.; Skidmore, Andrew K.; van der Werff, Harald M. A.; Groen, Thomas A.; de Boer, Willem F.; Prins, Herbert H. T.; Kohi, Edward; Peel, Mike

    2013-10-01

    Phenological or plant age classification across a landscape allows for examination of micro-topographical effects on plant growth, improvement in the accuracy of species discrimination, and will improve our understanding of the spatial variation in plant growth. In this paper six vegetation indices used in phenological studies (including the newly proposed PhIX index) were analysed for their ability to statistically differentiate grasses of different ages in the sequence of their development. Spectra of grasses of different ages were collected from a greenhouse study. These were used to determine if NDVI, NDWI, CAI, EVI, EVI2 and the newly proposed PhIX index could sequentially discriminate grasses of different ages, and subsequently classify grasses into their respective age category. The PhIX index was defined as: (AVNIRn+log(ASWIR2n))/(AVNIRn-log(ASWIR2n)), where AVNIRn and ASWIR2n are the respective normalised areas under the continuum removed reflectance curve within the VNIR (500-800 nm) and SWIR2 (2000-2210 nm) regions. The PhIX index was found to produce the highest phenological classification accuracy (Overall Accuracy: 79%, and Kappa Accuracy: 75%) and similar to the NDVI, EVI and EVI2 indices it statistically sequentially separates out the developmental age classes. Discrimination between seedling and dormant age classes and the adult and flowering classes was problematic for most of the tested indices. Combining information from the visible near infrared (VNIR) and shortwave infrared region (SWIR) region into a single phenological index captures the phenological changes associated with plant pigments and the ligno-cellulose absorption feature, providing a robust method to discriminate the age classes of grasses. This work provides a valuable contribution into mapping spatial variation and monitoring plant growth across savanna and grassland ecosystems.

  9. Psychological and physiological effect in humans of touching plant foliage - using the semantic differential method and cerebral activity as indicators

    PubMed Central

    2013-01-01

    Background Numerous studies have reported on the healing powers of plants and nature, but there have not been so many instances of experimental research. In particular, there are very few psychological and physiological studies using tactile stimuli. This study examines the psychological and physiological effects of touching plant foliage by using an evaluation profile of the subjects’ impressions and investigating cerebral blood flow. Methods The subjects were 14 young Japanese men aged from 21 to 27 years (mean ± standard deviation: 23.6 ± 2.4). With their eyes closed, the subjects touched four different tactile samples including a leaf of natural pothos (Epipremnum aureum). The physiological indices were compared before and after each stimulus. Psychological indices were obtained using a ‘semantic differential’ method. Results The fabric stimulus gave people ‘soft’ and ‘rough’ impressions, ‘kind’, ‘peaceful’ and ‘pleasant’ feelings psychologically, and a sense of physiological calm. On the other hand, the metal stimulus gave people ‘cold’, ‘smooth’ and ‘hard’ impressions and an image of something ‘artificial’. The metal stimulus caused a stress response in human cerebral blood flow although its evaluation in terms of ‘pleasant or unpleasant’ was neutral. There were no remarkable differences between the stimuli of natural and artificial pothos compared with other types of stimulus psychologically. However, only the natural pothos stimulus showed a sense of physiological calm in the same appearance as the fabric stimulus. Conclusions This study shows that people experience an unconscious calming reaction to touching a plant. It is to be concluded that plants are an indispensable element of the human environment. PMID:23587233

  10. Another Look at Semantic Relational Categories and Language Impairment.

    ERIC Educational Resources Information Center

    Stockman, Ida J.

    1992-01-01

    Types of utterances (with locative action utterances specifically differentiated) were evaluated in a language-impaired child tracked between one year, six months and three years of age. Comparison with utterances in other children suggests the importance of such a fine-grained analysis in detecting semantic properties of child language…

  11. Differential Responses to Adjuvants of Macrophages from Young Virgin, Aging Virgin and Aging Breeder Mice.

    DTIC Science & Technology

    1985-12-01

    Rb-Ai.62 483 DIFFERENTIAL RESPONSES TO ADJUVANTS OF MACROPHAGES FROM i/i YOUNG VIRGIN AGIN (U) MINNESOTA UNIV DULUTH DEPT OF MEDICAL MICROBIOLOGY RN...ADDRESS (City, State. an ZI 0EC 18 198E- Dept. of Medical Microbiology & Immunology 800 N. Quincy Street E1 8 Duluth, MN 55812-2487 Arlington, VA 22217-5...Aging Breeder Mice by Pamela R. Petrequin and Arthur G. Johnson Dept. of Medical Microbiology /Immunology University of Minnesota-Duluth School of

  12. Differential age effects on spatial and visual working memory.

    PubMed

    Oosterman, Joukje M; Morel, Sascha; Meijer, Lisette; Buvens, Cléo; Kessels, Roy P C; Postma, Albert

    2011-01-01

    The present study was intended to compare age effects on visual and spatial working memory by using two versions of the same task that differed only in presentation mode. The working memory task contained both a simultaneous and a sequential presentation mode condition, reflecting, respectively, visual and spatial working memory processes. Young and older participants had to remember the locations of five equal objects under three different conditions: a baseline (immediate recall), a maintenance (including a delay of 5 seconds), and a manipulation (e.g., relocate all objects one column to the right) condition. Only older adults performed worse on the sequential compared to the simultaneous baseline condition and only this group revealed lower performance on the sequential delay compared to the simultaneous delay condition. However, in both groups the manipulation condition affected performance on the simultaneous and sequential presentation modes to the same extent. The findings of this study therefore partially support an age-related differentiation between visual and spatial working memory, with a stronger age effect on spatial than on visual working memory.

  13. Attitudes about Aging and Gender among Young, Middle Age, and Older College-Based Students

    ERIC Educational Resources Information Center

    Laditka, Sarah B.; Fischer, Mary; Laditka, James N.; Segal, David R.

    2004-01-01

    Using an updated version of the Aging Semantic Differential, 534 younger, middle age, and older participants from a college community rated female and male targets categorized as ages 21-34 and 75-85. Participants also provided views about their own aging. Repeated measures of analysis of variance examined attitudinal differences by age and gender…

  14. Epigenome-Wide Scans Identify Differentially Methylated Regions for Age and Age-Related Phenotypes in a Healthy Ageing Population

    PubMed Central

    Yang, Tsun-Po; Pidsley, Ruth; Nisbet, James; Glass, Daniel; Mangino, Massimo; Zhai, Guangju; Zhang, Feng; Valdes, Ana; Shin, So-Youn; Dempster, Emma L.; Murray, Robin M.; Grundberg, Elin; Hedman, Asa K.; Nica, Alexandra; Small, Kerrin S.; Dermitzakis, Emmanouil T.; McCarthy, Mark I.; Mill, Jonathan; Spector, Tim D.; Deloukas, Panos

    2012-01-01

    Age-related changes in DNA methylation have been implicated in cellular senescence and longevity, yet the causes and functional consequences of these variants remain unclear. To elucidate the role of age-related epigenetic changes in healthy ageing and potential longevity, we tested for association between whole-blood DNA methylation patterns in 172 female twins aged 32 to 80 with age and age-related phenotypes. Twin-based DNA methylation levels at 26,690 CpG-sites showed evidence for mean genome-wide heritability of 18%, which was supported by the identification of 1,537 CpG-sites with methylation QTLs in cis at FDR 5%. We performed genome-wide analyses to discover differentially methylated regions (DMRs) for sixteen age-related phenotypes (ap-DMRs) and chronological age (a-DMRs). Epigenome-wide association scans (EWAS) identified age-related phenotype DMRs (ap-DMRs) associated with LDL (STAT5A), lung function (WT1), and maternal longevity (ARL4A, TBX20). In contrast, EWAS for chronological age identified hundreds of predominantly hyper-methylated age DMRs (490 a-DMRs at FDR 5%), of which only one (TBX20) was also associated with an age-related phenotype. Therefore, the majority of age-related changes in DNA methylation are not associated with phenotypic measures of healthy ageing in later life. We replicated a large proportion of a-DMRs in a sample of 44 younger adult MZ twins aged 20 to 61, suggesting that a-DMRs may initiate at an earlier age. We next explored potential genetic and environmental mechanisms underlying a-DMRs and ap-DMRs. Genome-wide overlap across cis-meQTLs, genotype-phenotype associations, and EWAS ap-DMRs identified CpG-sites that had cis-meQTLs with evidence for genotype–phenotype association, where the CpG-site was also an ap-DMR for the same phenotype. Monozygotic twin methylation difference analyses identified one potential environmentally-mediated ap-DMR associated with total cholesterol and LDL (CSMD1). Our results suggest that in a

  15. Common and differential electrophysiological mechanisms underlying semantic object memory retrieval probed by features presented in different stimulus types.

    PubMed

    Chiang, Hsueh-Sheng; Eroh, Justin; Spence, Jeffrey S; Motes, Michael A; Maguire, Mandy J; Krawczyk, Daniel C; Brier, Matthew R; Hart, John; Kraut, Michael A

    2016-08-01

    How the brain combines the neural representations of features that comprise an object in order to activate a coherent object memory is poorly understood, especially when the features are presented in different modalities (visual vs. auditory) and domains (verbal vs. nonverbal). We examined this question using three versions of a modified Semantic Object Retrieval Test, where object memory was probed by a feature presented as a written word, a spoken word, or a picture, followed by a second feature always presented as a visual word. Participants indicated whether each feature pair elicited retrieval of the memory of a particular object. Sixteen subjects completed one of the three versions (N=48 in total) while their EEG were recorded simultaneously. We analyzed EEG data in four separate frequency bands (delta: 1-4Hz, theta: 4-7Hz; alpha: 8-12Hz; beta: 13-19Hz) using a multivariate data-driven approach. We found that alpha power time-locked to response was modulated by both cross-modality (visual vs. auditory) and cross-domain (verbal vs. nonverbal) probing of semantic object memory. In addition, retrieval trials showed greater changes in all frequency bands compared to non-retrieval trials across all stimulus types in both response-locked and stimulus-locked analyses, suggesting dissociable neural subcomponents involved in binding object features to retrieve a memory. We conclude that these findings support both modality/domain-dependent and modality/domain-independent mechanisms during semantic object memory retrieval.

  16. Revisiting dark energy models using differential ages of galaxies

    NASA Astrophysics Data System (ADS)

    Rani, Nisha; Jain, Deepak; Mahajan, Shobhit; Mukherjee, Amitabha; Biesiada, Marek

    2017-03-01

    In this work, we use a test based on the differential ages of galaxies for distinguishing the dark energy models. As proposed by Jimenez and Loeb in [1], relative ages of galaxies can be used to put constraints on various cosmological parameters. In the same vein, we reconstruct H0dt/dz and its derivative (H0d2t/dz2) using a model independent technique called non-parametric smoothing. Basically, dt/dz is the change in the age of the object as a function of redshift which is directly linked with the Hubble parameter. Hence for reconstruction of this quantity, we use the most recent H(z) data. Further, we calculate H0dt/dz and its derivative for several models like Phantom, Einstein de Sitter (EdS), ΛCDM, Chevallier-Polarski-Linder (CPL) parametrization, Jassal-Bagla-Padmanabhan (JBP) parametrization and Feng-Shen-Li-Li (FSLL) parametrization. We check the consistency of these models with the results of reconstruction obtained in a model independent way from the data. It is observed that H0dt/dz as a tool is not able to distinguish between the ΛCDM, CPL, JBP and FSLL parametrizations but, as expected, EdS and Phantom models show noticeable deviation from the reconstructed results. Further, the derivative of H0dt/dz for various dark energy models is more sensitive at low redshift. It is found that the FSLL model is not consistent with the reconstructed results, however, the ΛCDM model is in concordance with the 3σ region of the reconstruction at redshift z>= 0.3.

  17. Another look at semantic relational categories and language impairment.

    PubMed

    Stockman, I J

    1992-01-01

    Earlier comparative studies of language-impaired and normal children involved semantic-relational analyses of broad categories (e.g., action, locative action, and so on) in which utterance types were not differentiated. In this study, locative action utterances were differentiated by the types of locative words used singly and in combination. The types of utterances used by a language-impaired child were tracked between 1 year 6 months and 3 years and compared with those of three age- and MLU-matched normal children. The results suggested that differences in the semantic properties of language-impaired and normal children's utterances may go undetected unless a fine-grained analysis is performed on the types of expressions used within a global relational category. The potential value of extending semantic-relational analyses by exploring word use in syntactic contexts is addressed.

  18. "Dyslexia": Toward Semantical Clarification.

    ERIC Educational Resources Information Center

    Manzo, Anthony V.; Duffelmeyer, Fred

    A formulated definition of the term dyslexia is proposed in this paper in order to clarify the semantical confusion which exists among both specialists and the general public. Dyslexia is explained as a generic term for severe and puzzling reading disability, found to be both acute (where reading-age lags 25 percent or more below mental age) and…

  19. Toward a Nonspeech Test of Auditory Cognition: Semantic Context Effects in Environmental Sound Identification in Adults of Varying Age and Hearing Abilities

    PubMed Central

    Sheft, Stanley; Norris, Molly; Spanos, George; Radasevich, Katherine; Formsma, Paige; Gygi, Brian

    2016-01-01

    Objective Sounds in everyday environments tend to follow one another as events unfold over time. The tacit knowledge of contextual relationships among environmental sounds can influence their perception. We examined the effect of semantic context on the identification of sequences of environmental sounds by adults of varying age and hearing abilities, with an aim to develop a nonspeech test of auditory cognition. Method The familiar environmental sound test (FEST) consisted of 25 individual sounds arranged into ten five-sound sequences: five contextually coherent and five incoherent. After hearing each sequence, listeners identified each sound and arranged them in the presentation order. FEST was administered to young normal-hearing, middle-to-older normal-hearing, and middle-to-older hearing-impaired adults (Experiment 1), and to postlingual cochlear-implant users and young normal-hearing adults tested through vocoder-simulated implants (Experiment 2). Results FEST scores revealed a strong positive effect of semantic context in all listener groups, with young normal-hearing listeners outperforming other groups. FEST scores also correlated with other measures of cognitive ability, and for CI users, with the intelligibility of speech-in-noise. Conclusions Being sensitive to semantic context effects, FEST can serve as a nonspeech test of auditory cognition for diverse listener populations to assess and potentially improve everyday listening skills. PMID:27893791

  20. Reading Development Electrified: Semantic and Syntactic Integration during Sentence Comprehension in School-Age Children and Young Adults

    ERIC Educational Resources Information Center

    VanDyke, Justine M.

    2011-01-01

    Adults are able to access semantic and syntactic information rapidly as they hear or read in real-time in order to interpret sentences. Young children, on the other hand, tend to rely on syntactically-based parsing routines, adopting the first noun as the agent of a sentence regardless of plausibility, at least during oral comprehension. Little is…

  1. Young Children's Flexible Use of Semantic Cues to Word Meanings: Converging Evidence of Individual and Age Differences

    ERIC Educational Resources Information Center

    Deák, Gedeon O.; Narasimham, Gayathri

    2014-01-01

    A new test of children's flexible use of semantic cues for word learning extended previous results. In Experiment 1, three- to five-year-olds (N = 51) completed two tests of interpreting several novel words for the same stimulus arrays. Within-sentence phrasal cues implied different stimulus referent properties. Children's cue-using…

  2. Syntactic and Semantic Characteristics in the Written Language of Hearing Impaired and Normally Hearing School-Aged Children.

    ERIC Educational Resources Information Center

    Yoshinaga, Christine

    To investigate semantic and syntactic variables in the written language of normally hearing and hearing impaired children, 49 hearing impaired and 49 normally hearing children (10-14 years old) were asked to write compositions based on the Accident/Emergency Picture in the Peabody Language Development Kit. In addition, syntactic characteristics…

  3. Conceptual Organization at 6 and 8 Years of Age: Evidence from the Semantic Priming of Object Decisions

    ERIC Educational Resources Information Center

    Hashimoto, Naomi; McGregor, Karla K.; Graham, Anne

    2007-01-01

    Purpose: The purpose of this study was to examine children's knowledge of semantic relations. Method: In Experiment 1, the 6-year-olds, 8-year-olds, and adults participated in an object decision task. Participants in the primed group made object decisions in response to primes that were related taxonomically, thematically, or perceptually to the…

  4. Productive Extension of Semantic Memory in School-Aged Children: Relations with Reading Comprehension and Deployment of Cognitive Resources

    ERIC Educational Resources Information Center

    Bauer, Patricia J.; Blue, Shala N.; Xu, Aoxiang; Esposito, Alena G.

    2016-01-01

    We investigated 7- to 10-year-old children's productive extension of semantic memory through self-generation of new factual knowledge derived through integration of separate yet related facts learned through instruction or through reading. In Experiment 1, an experimenter read the to-be-integrated facts. Children successfully learned and…

  5. Testosterone and Dihydrotestosterone Differentially Improve Cognition in Aged Female Mice

    ERIC Educational Resources Information Center

    Benice, Ted S.; Raber, Jacob

    2009-01-01

    Compared with age-matched male mice, female mice experience a more severe age-related cognitive decline (ACD). Since androgens are less abundant in aged female mice compared with aged male mice, androgen supplementation may enhance cognition in aged female mice. To test this, we assessed behavioral performance on a variety of tasks in 22- to…

  6. A systemic-wholistic approach to differential aging: longitudinal findings from the Berlin Aging Study.

    PubMed

    Gerstorf, Denis; Smith, Jacqui; Baltes, Paul B

    2006-12-01

    Wholistic perspectives on differential change focus on multiple-indicator information at a person level. They supplement the modeling of average trajectories at a variable level. The authors extended cross-sectional work in the Berlin Aging Study (J. Smith & P. B. Baltes, 1997) to 6-year longitudinal cluster analyses (n = 132). At baseline, 3 subgroups were identified with distinct within-person psychological profiles across cognitive, personality, and social integration constructs. Over time, highly similar subgroup profiles were found, and about two thirds of the participants could be classified as remaining in the same subgroups. Baseline subgroups differed in level and slope of change and in 2 outcomes, well-being and mortality. Independent of subgroup membership, subgroup-to-subgroup change was associated with greater decline and predicted poststudy mortality. These findings demonstrate the usefulness of a wholistic approach for long-term prediction of outcomes and within-person systemic variability.

  7. Differentiating semantic categories during the acquisition of novel words: correspondence analysis applied to event-related potentials.

    PubMed

    Fargier, Raphaël; Ploux, Sabine; Cheylus, Anne; Reboul, Anne; Paulignan, Yves; Nazir, Tatjana A

    2014-11-01

    Growing evidence suggests that semantic knowledge is represented in distributed neural networks that include modality-specific structures. Here, we examined the processes underlying the acquisition of words from different semantic categories to determine whether the emergence of visual- and action-based categories could be tracked back to their acquisition. For this, we applied correspondence analysis (CA) to ERPs recorded at various moments during acquisition. CA is a multivariate statistical technique typically used to reveal distance relationships between words of a corpus. Applied to ERPs, it allows isolating factors that best explain variations in the data across time and electrodes. Participants were asked to learn new action and visual words by associating novel pseudowords with the execution of hand movements or the observation of visual images. Words were probed before and after training on two consecutive days. To capture processes that unfold during lexical access, CA was applied on the 100-400 msec post-word onset interval. CA isolated two factors that organized the data as a function of test sessions and word categories. Conventional ERP analyses further revealed a category-specific increase in the negativity of the ERPs to action and visual words at the frontal and occipital electrodes, respectively. The distinct neural processes underlying action and visual words can thus be tracked back to the acquisition of word-referent relationships and may have its origin in association learning. Given current evidence for the flexibility of language-induced sensory-motor activity, we argue that these associative links may serve functions beyond word understanding, that is, the elaboration of situation models.

  8. Differential Effects of Aging on Processes Underlying Task Switching

    ERIC Educational Resources Information Center

    West, Robert; Travers, Stephanie

    2008-01-01

    In this study, we used event-related brain potentials (ERPs) to examine the effects of aging on processes underlying task switching. The response time data revealed an age-related increase in mixing costs before controlling for general slowing and no effect of aging on switching costs. In the cue-locked epoch, the ERP data revealed little effect…

  9. The diagnostic accuracy of an incidental memory modification of the Boston Naming Test (memo-BNT) in differentiating between normal aging and mild Alzheimer's disease.

    PubMed

    Karrasch, Mira; Myllyniemi, Anna; Latvasalo, Linda; Söderholm, Carina; Ellfolk, Ulla; Laine, Matti

    2010-11-01

    Early Alzheimer's disease (AD) is associated with deficits in episodic memory. Semantic memory and naming have also been found to be affected, although to a lesser degree than episodic memory. Most episodic memory tests used in clinical settings assess intentional memory. The aim of the present paper was to present an incidental memory modification of the Boston Naming Test (memo-BNT) and to study the diagnostic accuracy of the BNT and the memo-BNT in differentiating between healthy old controls and AD patients. There were three groups in the study: 22 young controls (mean age 21.7), 23 normally aged old controls (mean age 70.6), and 23 patients with mild AD (mean age 74.0). There were no differences in the memo-BNT test scores between the old and young control participants. There were, however, significant differences between the AD patients and both control groups in several of the memo-BNT measures. Incidental free recall was the best measure in discriminating between the healthy aged controls and the AD patients (AUC = .939) and it had a better diagnostic accuracy than naming (AUC = 880). The results indicate that the memo-BNT could be used in clinical settings especially to differentiate between normal aging and mild AD.

  10. Knowledge of and Attitudes toward Aging in Young, Middle-Aged, and Older College Students: A Comparison of Two Measures of Knowledge of Aging.

    ERIC Educational Resources Information Center

    O'Hanlon, Ann M.; And Others

    1993-01-01

    Palmore's Facts on Aging Quiz, Knowledge of Aging and the Elderly scale, and Aging Semantic Differential were completed by 387 college students aged 17-85. Knowledge scores were not related to measures of attitudes toward older adults. Older students had higher knowledge scores and more positive attitudes. (SK)

  11. Contribution of Pretesting to Several Measures of Semantic Desensitization Effectiveness

    ERIC Educational Resources Information Center

    Israel, Allen C.; And Others

    1977-01-01

    Snake- or spider-phobic subjects (N=32) were randomly assigned to one of four groups. Subjects receiving semantic desensitization therapy showed less posttest anxiety on the semantic differential than control subjects regardless of testing condition. (Author)

  12. Age and amount of exposure to a foreign language during childhood: behavioral and ERP data on the semantic comprehension of spoken English by Japanese children.

    PubMed

    Ojima, Shiro; Matsuba-Kurita, Hiroko; Nakamura, Naoko; Hoshino, Takahiro; Hagiwara, Hiroko

    2011-06-01

    Children's foreign-language (FL) learning is a matter of much social as well as scientific debate. Previous behavioral research indicates that starting language learning late in life can lead to problems in phonological processing. Inadequate phonological capacity may impede lexical learning and semantic processing (phonological bottleneck hypothesis). Using both behavioral and neuroimaging data, here we examine the effects of age of first exposure (AOFE) and total hours of exposure (HOE) to English, on 350 Japanese primary-school children's semantic processing of spoken English. Children's English proficiency scores and N400 event-related brain potentials (ERPs) were analyzed in multiple regression analyses. The results showed (1) that later, rather than earlier, AOFE led to higher English proficiency and larger N400 amplitudes, when HOE was controlled for; and (2) that longer HOE led to higher English proficiency and larger N400 amplitudes, whether AOFE was controlled for or not. These data highlight the important role of amount of exposure in FL learning, and cast doubt on the view that starting FL learning earlier always produces better results.

  13. Neural Substrates of Semantic Prospection – Evidence from the Dementias

    PubMed Central

    Irish, Muireann; Eyre, Nadine; Dermody, Nadene; O’Callaghan, Claire; Hodges, John R.; Hornberger, Michael; Piguet, Olivier

    2016-01-01

    The ability to envisage personally relevant events at a future time point represents an incredibly sophisticated cognitive endeavor and one that appears to be intimately linked to episodic memory integrity. Far less is known regarding the neurocognitive mechanisms underpinning the capacity to envisage non-personal future occurrences, known as semantic future thinking. Moreover the degree of overlap between the neural substrates supporting episodic and semantic forms of prospection remains unclear. To this end, we sought to investigate the capacity for episodic and semantic future thinking in Alzheimer’s disease (n = 15) and disease-matched behavioral-variant frontotemporal dementia (n = 15), neurodegenerative disorders characterized by significant medial temporal lobe (MTL) and frontal pathology. Participants completed an assessment of past and future thinking across personal (episodic) and non-personal (semantic) domains, as part of a larger neuropsychological battery investigating episodic and semantic processing, and their performance was contrasted with 20 age- and education-matched healthy older Controls. Participants underwent whole-brain T1-weighted structural imaging and voxel-based morphometry analysis was conducted to determine the relationship between gray matter integrity and episodic and semantic future thinking. Relative to Controls, both patient groups displayed marked future thinking impairments, extending across episodic and semantic domains. Analyses of covariance revealed that while episodic future thinking deficits could be explained solely in terms of episodic memory proficiency, semantic prospection deficits reflected the interplay between episodic and semantic processing. Distinct neural correlates emerged for each form of future simulation with differential involvement of prefrontal, lateral temporal, and medial temporal regions. Notably, the hippocampus was implicated irrespective of future thinking domain, with the suggestion of

  14. Neural Substrates of Semantic Prospection - Evidence from the Dementias.

    PubMed

    Irish, Muireann; Eyre, Nadine; Dermody, Nadene; O'Callaghan, Claire; Hodges, John R; Hornberger, Michael; Piguet, Olivier

    2016-01-01

    The ability to envisage personally relevant events at a future time point represents an incredibly sophisticated cognitive endeavor and one that appears to be intimately linked to episodic memory integrity. Far less is known regarding the neurocognitive mechanisms underpinning the capacity to envisage non-personal future occurrences, known as semantic future thinking. Moreover the degree of overlap between the neural substrates supporting episodic and semantic forms of prospection remains unclear. To this end, we sought to investigate the capacity for episodic and semantic future thinking in Alzheimer's disease (n = 15) and disease-matched behavioral-variant frontotemporal dementia (n = 15), neurodegenerative disorders characterized by significant medial temporal lobe (MTL) and frontal pathology. Participants completed an assessment of past and future thinking across personal (episodic) and non-personal (semantic) domains, as part of a larger neuropsychological battery investigating episodic and semantic processing, and their performance was contrasted with 20 age- and education-matched healthy older Controls. Participants underwent whole-brain T1-weighted structural imaging and voxel-based morphometry analysis was conducted to determine the relationship between gray matter integrity and episodic and semantic future thinking. Relative to Controls, both patient groups displayed marked future thinking impairments, extending across episodic and semantic domains. Analyses of covariance revealed that while episodic future thinking deficits could be explained solely in terms of episodic memory proficiency, semantic prospection deficits reflected the interplay between episodic and semantic processing. Distinct neural correlates emerged for each form of future simulation with differential involvement of prefrontal, lateral temporal, and medial temporal regions. Notably, the hippocampus was implicated irrespective of future thinking domain, with the suggestion of

  15. Differentiation of Occupational Perceptions Among Different Age Groups

    ERIC Educational Resources Information Center

    Edwards, Keith J.; And Others

    1974-01-01

    Hypothesizes that occupational perceptions are more specific for older age groups than for younger age groups. Hypothesis was tested by using latent root analysis and minimum residual factor analysis to analyze intercorrelations among six Vocational Preference Inventory (VPI) scales for five large and diverse samples. Both analyses supported the…

  16. Learning Styles in the Age of Differentiated Instruction

    ERIC Educational Resources Information Center

    Landrum, Timothy J.; McDuffie, Kimberly A.

    2010-01-01

    The concept of learning styles has tremendous logical and intuitive appeal, and educators' desire to focus on learning styles is understandable. Recently, a growing emphasis on differentiated instruction may have further increased teachers' tendency to look at learning styles as an instructionally relevant variable when individualizing instruction…

  17. Differential effects of young maternal age on child growth

    PubMed Central

    Yu, Soo Hyun; Mason, John; Crum, Jennifer; Cappa, Claudia; Hotchkiss, David R.

    2016-01-01

    Background The association of early maternal birthing age with smaller children has been widely observed. However, it is unclear if this is due to confounding by factors such as socioeconomic status, or the age at which child growth restriction first occurs. Objective To examine the effect of early maternal birthing age on the first-born child's height-for-age in a sample of developing countries in Africa, Asia, and Latin America. Design Cross-sectional data from Demographic Health Surveys from 18 countries were used, to select the first-born child of mothers aged 15–24 years and a range of potential confounding factors, including maternal height. Child length/height-for-age z-scores (HAZs) was estimated in age bands of 0–11, 12–23, 24–35, 36–47, and 48–59 months; HAZ was first compared between maternal age groups of 15–17, 18–19, and 20–24 years. Results 1) There were significant bivariate associations between low child HAZ and young maternal age (71 of 180 possible cases; at p<0.10), but the majority of these did not persist when controlling for confounders (41 cases, 23% of the 180). 2) For children <12 months, when controlling for confounders, three out of seven Asian countries showed a significant association between lower infant HAZ and low maternal age, as did six out of nine African countries (15–17 or 15–19 years vs. the older group). 3) The association (adjusted) continued after 24 months in 12 of the 18 countries, in Africa, Asia, and Latin America. 4) The stunting differences for children between maternal age groups were around 9 percentage points (ppts) in Asia, 14 ppts in Africa, and 10 ppts in Latin America. These data do not show whether this is due to, for example, socioeconomic factors that were not included, an emerging effect of intrauterine growth restriction, or the child feeding or caring behaviors of young mothers. The latter is considered to be the most likely. Conclusions The effect of low maternal age on child height

  18. Differential effects of young maternal age on child growth.

    PubMed

    Yu, Soo Hyun; Mason, John; Crum, Jennifer; Cappa, Claudia; Hotchkiss, David R

    2016-01-01

    Background The association of early maternal birthing age with smaller children has been widely observed. However, it is unclear if this is due to confounding by factors such as socioeconomic status, or the age at which child growth restriction first occurs. Objective To examine the effect of early maternal birthing age on the first-born child's height-for-age in a sample of developing countries in Africa, Asia, and Latin America. Design Cross-sectional data from Demographic Health Surveys from 18 countries were used, to select the first-born child of mothers aged 15-24 years and a range of potential confounding factors, including maternal height. Child length/height-for-age z-scores (HAZs) was estimated in age bands of 0-11, 12-23, 24-35, 36-47, and 48-59 months; HAZ was first compared between maternal age groups of 15-17, 18-19, and 20-24 years. Results 1) There were significant bivariate associations between low child HAZ and young maternal age (71 of 180 possible cases; at p<0.10), but the majority of these did not persist when controlling for confounders (41 cases, 23% of the 180). 2) For children <12 months, when controlling for confounders, three out of seven Asian countries showed a significant association between lower infant HAZ and low maternal age, as did six out of nine African countries (15-17 or 15-19 years vs. the older group). 3) The association (adjusted) continued after 24 months in 12 of the 18 countries, in Africa, Asia, and Latin America. 4) The stunting differences for children between maternal age groups were around 9 percentage points (ppts) in Asia, 14 ppts in Africa, and 10 ppts in Latin America. These data do not show whether this is due to, for example, socioeconomic factors that were not included, an emerging effect of intrauterine growth restriction, or the child feeding or caring behaviors of young mothers. The latter is considered to be the most likely. Conclusions The effect of low maternal age on child height restriction from 0 to

  19. Transcriptional analysis of histone deacetylase family members reveal similarities between differentiating and aging spermatogonial stem cells.

    PubMed

    Kofman, Amber E; Huszar, Jessica M; Payne, Christopher J

    2013-02-01

    The differentiation of adult stem cells involves extensive chromatin remodeling, mediated in part by the gene products of histone deacetylase (HDAC) family members. While the transcriptional downregulation of HDACs can impede stem cell self-renewal in certain contexts, it may also promote stem cell maintenance under other circumstances. In self-renewing, differentiating, and aging spermatogonial stem cells (SSCs), the gene expression dynamics of HDACs have not yet been characterized. To gain further insight with these studies, we analyzed the transcriptional profiles of six HDAC family members, previously identified to be the most highly expressed in self-renewing SSCs, during stem cell differentiation and aging. Here we discovered that in both differentiating and aging SSCs the expression of Sirt4 increases, while the expression of Hdac2, Hdac6, and Sirt1 decreases. When SSCs are exposed to the lifespan-enhancing drug rapamycin in vivo, the resultant HDAC gene expression patterns are opposite of those seen in the differentiating and aging SSCs, with increased Hdac2, Hdac6, and Sirt1 and decreased Hdac8, Hdac9, and Sirt4. Our findings suggest that HDACs important for stem cell maintenance and oxidative capacity are downregulated as adult stem cells differentiate or age. These results provide important insights into the epigenetic regulation of stem cell differentiation and aging in mammals.

  20. Differential expression of sirtuins in the aging rat brain

    PubMed Central

    Braidy, Nady; Poljak, Anne; Grant, Ross; Jayasena, Tharusha; Mansour, Hussein; Chan-Ling, Tailoi; Smythe, George; Sachdev, Perminder; Guillemin, Gilles J.

    2015-01-01

    Although there are seven mammalian sirtuins (SIRT1-7), little is known about their expression in the aging brain. To characterize the change(s) in mRNA and protein expression of SIRT1-7 and their associated proteins in the brain of “physiologically” aged Wistar rats. We tested mRNA and protein expression levels of rat SIRT1-7, and the levels of associated proteins in the brain using RT-PCR and western blotting. Our data shows that SIRT1 expression increases with age, concurrently with increased acetylated p53 levels in all brain regions investigated. SIRT2 and FOXO3a protein levels increased only in the occipital lobe. SIRT3-5 expression declined significantly in the hippocampus and frontal lobe, associated with increases in superoxide and fatty acid oxidation levels, and acetylated CPS-1 protein expression, and a reduction in MnSOD level. While SIRT6 expression declines significantly with age acetylated H3K9 protein expression is increased throughout the brain. SIRT7 and Pol I protein expression increased in the frontal lobe. This study identifies previously unknown roles for sirtuins in regulating cellular homeostasis and healthy aging. PMID:26005404

  1. Development of a Bone-Conducted Ultrasonic Hearing Aid for the Profoundly Deaf: Evaluation of Sound Quality Using a Semantic Differential Method

    NASA Astrophysics Data System (ADS)

    Nakagawa, Seiji; Fujiyuki, Chika; Kagomiya, Takayuki

    2013-07-01

    Bone-conducted ultrasound (BCU) is perceived even by the profoundly sensorineural deaf. A novel hearing aid using the perception of amplitude-modulated BCU (BCU hearing aid: BCUHA) has been developed. However, there is room for improvement particularly in terms of sound quality. BCU speech is accompanied by a strong high-pitched tone and contain some distortion. In this study, the sound quality of BCU speech with several types of amplitude modulation [double-sideband with transmitted carrier (DSB-TC), double-sideband with suppressed carrier (DSB-SC), and transposed modulations] and air-conducted (AC) speech was quantitatively evaluated using semantic differential and factor analysis. The results showed that all the types of BCU speech had higher metallic and lower esthetic factor scores than AC speech. On the other hand, transposed speech was closer than the other types of BCU speech to AC speech generally; the transposed speech showed a higher powerfulness factor score than the other types of BCU speech and a higher esthetic factor score than DSB-SC speech. These results provide useful information for further development of the BCUHA.

  2. Differential Age Effects on Spatial and Visual Working Memory

    ERIC Educational Resources Information Center

    Oosterman, Joukje M.; Morel, Sascha; Meijer, Lisette; Buvens, Cleo; Kessels, Roy P. C.; Postma, Albert

    2011-01-01

    The present study was intended to compare age effects on visual and spatial working memory by using two versions of the same task that differed only in presentation mode. The working memory task contained both a simultaneous and a sequential presentation mode condition, reflecting, respectively, visual and spatial working memory processes. Young…

  3. Generative Semantics

    ERIC Educational Resources Information Center

    Bagha, Karim Nazari

    2011-01-01

    Generative semantics is (or perhaps was) a research program within linguistics, initiated by the work of George Lakoff, John R. Ross, Paul Postal and later McCawley. The approach developed out of transformational generative grammar in the mid 1960s, but stood largely in opposition to work by Noam Chomsky and his students. The nature and genesis of…

  4. Vocal reaction times to unilaterally presented concrete and abstract words: towards a theory of differential right hemispheric semantic processing.

    PubMed

    Rastatter, M; Dell, C W; McGuire, R A; Loren, C

    1987-03-01

    Previous studies investigating hemispheric organization for processing concrete and abstract nouns have provided conflicting results. Using manual reaction time tasks some studies have shown that the right hemisphere is capable of analyzing concrete words but not abstract. Others, however, have inferred that the left hemisphere is the sole analyzer of both types of lexicon. The present study tested these issues further by measuring vocal reaction times of normal subjects to unilaterally presented concrete and abstract items. Results were consistent with a model of functional localization which suggests that the minor hemisphere is capable of differentially processing both types of lexicon in the presence of a dominant left hemisphere.

  5. SES differentials in health by age and alternative indicators of SES.

    PubMed

    Robert, S; House, J S

    1996-08-01

    Despite the general persistence and even increase of strong socioeconomic status (SES) differentials in health in the United States, research suggests that SES differentials in health may diminish or become nonexistent at older ages. However, most research has used only limited measures of SES (e.g. education, income), and has not thoroughly investigated intra-elderly age differences in this trend. The current study investigates how SES differentials in health vary by age in the United States, using fairly detailed age categories (through ages 85+), and 2 alternative indicators (home ownership and liquid assets) of a major additional dimension of SES, financial assets, which may be especially important at older ages. We address (a) how strongly financial assets are associated with health, considered both alone and net of education and income; (b) if the health effects of financial assets vary by age; and, more specifically, (c) if their effects are especially pronounced in older age, again considered both alone and net of or relative to education and income. Results show that financial assets, especially liquid assets, considered both alone and net of education and income, are associated with health throughout adulthood and old age, at least until ages 85+. Furthermore, financial assets remain associated with health until quite late in life and become more important relative to education and income at older ages for some measures of health.

  6. Ageing and disability: Job satisfaction differentials across Europe.

    PubMed

    Pagan, Ricardo

    2011-01-01

    This article analyses the levels of job satisfaction reported by older workers (aged 50-64) with and without disabilities at a European level. Using data from the Survey of Health, Ageing and Retirement in Europe (2004 and 2007), we estimate job satisfaction equations for non-disabled, non-limited disabled and limited disabled workers, and decompose the observed job satisfaction gap by using the widely-used Oaxaca-Blinder methodology. The results show that after controlling for some variables, older workers with disabilities who are limited in their daily activities are less likely to be satisfied with their jobs as compared to their non-disabled counterparts. However, after estimating separate models for each group and doing the Oaxaca-Blinder decomposition, we found that older workers with limiting disabilities have greater returns in terms of job satisfaction from their job characteristics (such as wages, tenure and working in the private sector) as compared to non-disabled individuals. This finding supports the hypothesis of lower expectations about jobs of disadvantaged groups (e.g. limited disabled population) and has important public policy implications.

  7. Differential Age Effects for Implicit and Explicit Conceptual Associative Memory

    PubMed Central

    Dew, Ilana T. Z.; Giovanello, Kelly S.

    2010-01-01

    Older adults show disproportionate declines in explicit memory for associative relative to item information. However, the source of these declines is still uncertain. One explanation is a generalized impairment in the processing of associative information. A second explanation is a more specialized impairment in the strategic, effortful recollection of associative information, leaving less effortful forms of associative retrieval preserved. Assessing implicit memory of new associations is a way to distinguish between these viewpoints. To date, mixed findings have emerged from studies of associative priming in aging. One factor that may account for the variability is whether the manipulations inadvertently involve strategic, explicit processes. In 2 experiments we present a novel paradigm of conceptual associative priming in which subjects make speeded associative judgments about unrelated objects. Using a size classification task, Experiment 1 showed equivalent associative priming between young and older adults. Experiment 2 generalized the results of Experiment 1 to an inside/outside classification task, while replicating the typical age-related impairment in associative but not item recognition. Taken together, the findings support the viewpoint that older adults can incidentally encode and retrieve new meaningful associations despite difficulty with the intentional recollection of the same information. PMID:21077717

  8. Does Age Moderate the Effect of IQ on the Differentiation of Cognitive Abilities during Childhood?

    ERIC Educational Resources Information Center

    Facon, Bruno

    2006-01-01

    Data from the national standardization of the French version of the WISC-III were analyzed to determine when during childhood the IQ-related process of differentiation appears and how the strength of the relationships among subtests evolves with age in low- and high-IQ groups. Indeed, some recent studies suggest that age might moderate the effect…

  9. Complex and differential glial responses in Alzheimer's disease and ageing.

    PubMed

    Rodríguez, José J; Butt, Arthur M; Gardenal, Emanuela; Parpura, Vladimir; Verkhratsky, Alexei

    2016-01-01

    Glial cells and their association with neurones are fundamental for brain function. The emergence of complex neurone-glial networks assures rapid information transfer, creating a sophisticated circuitry where both types of neural cells work in concert, serving different activities. All glial cells, represented by astrocytes, oligodendrocytes, microglia and NG2-glia, are essential for brain homeostasis and defence. Thus, glia are key not only for normal central nervous system (CNS) function, but also to its dysfunction, being directly associated with all forms of neuropathological processes. Therefore, the progression and outcome of neurological and neurodegenerative diseases depend on glial reactions. In this review, we provide a concise account of recent data obtained from both human material and animal models demonstrating the pathological involvement of glia in neurodegenerative processes, including Alzheimer's disease (AD), as well as physiological ageing.

  10. Factors associated with the differential in actual gestational age and gestational age predicted from transrectal ultrasonography in pregnant dairy cows.

    PubMed

    Fitzgerald, A M; Ryan, D P; Berry, D P

    2015-08-01

    The objective of the study was to determine (1) how gestational age predicted using transrectal ultrasonography related to actual gestational age derived as the number of days from the most recent artificial insemination date, (2) what factors, if any, were associated with the differential between the two measures, and (3) the association between this differential in gestational age and the likelihood of subsequent pregnancy loss, stillbirth, or calving dystocia. The data set contained 7340 ultrasound records from 6805 Holstein Friesian dairy cows in 175 herds. Ultrasonography assessment underestimated gestational age relative to days since last service by 0.51 days (standard error [SE]: 0.040), although the differential was less during embryonic development phase (i.e., ≤42 days of gestation; mean overestimation of 0.31 days) versus fetal development phase (i.e., >42 days of gestation; mean underestimation of 0.81 days). Predicted calving date calculated from ultrasonography was 1.41 days (SE: 0.040) later than the actual subsequent calving date and was, on average, 0.52 days later than predicted calving date, assuming a gestation length of 282 days. Parity of the dam (P < 0.05), stage of pregnancy (P < 0.001), and sex of the calf born (P < 0.001) were all associated with the differential in gestational age based on ultrasonography versus days since last service. No obvious trend among parities was evident in the difference between the methods in predicting gestational age. Ultrasonography underestimated gestational age by 0.83 (SE: 0.15) days in parity 5+ cows and underestimated gestational age by 0.41 (SE: 0.14) days in the first-parity cows. Relative to gestational age predicted from the most recent service, ultrasonography underestimated gestational age by 0.75 (SE: 0.13) days for heifer fetuses and underestimated gestational age by 0.36 (SE: 0.13) days for bull fetuses. The heritability of the differential in gestational age between the methods of

  11. The happy survivor? Effects of differential mortality on life satisfaction in older age.

    PubMed

    Segerstrom, Suzanne C; Combs, Hannah L; Winning, Ashley; Boehm, Julia K; Kubzansky, Laura D

    2016-06-01

    Older adults report higher psychological well-being than younger adults. Those highest in well-being also have the lowest risk of mortality. If those with lower well-being die earlier, it could affect the appearance of developmental change in well-being. In adults aged 50 and older (N = 4,458), we estimated effects of differential mortality on life satisfaction by imputing life satisfaction, adjusting for attrition due to death, or estimating life satisfaction using pattern-mixture modeling. There was an increase in life satisfaction with age; however, differential mortality affected the elevation of the curve. Observed life satisfaction, particularly above age 70, is affected by differential mortality. (PsycINFO Database Record

  12. Quantifying Semantic Linguistic Maturity in Children

    ERIC Educational Resources Information Center

    Hansson, Kristina; Bååth, Rasmus; Löhndorf, Simone; Sahlén, Birgitta; Sikström, Sverker

    2016-01-01

    We propose a method to quantify "semantic linguistic maturity" (SELMA) based on a high dimensional semantic representation of words created from the co-occurrence of words in a large text corpus. The method was applied to oral narratives from 108 children aged 4;0-12;10. By comparing the SELMA measure with maturity ratings made by human…

  13. Rapidly Developing Yeast Microcolonies Differentiate in a Similar Way to Aging Giant Colonies

    PubMed Central

    Váchová, Libuše; Hatáková, Ladislava; Čáp, Michal; Pokorná, Michaela; Palková, Zdena

    2013-01-01

    During their development and aging on solid substrates, yeast giant colonies produce ammonia, which acts as a quorum sensing molecule. Ammonia production is connected with alkalization of the surrounding medium and with extensive reprogramming of cell metabolism. In addition, ammonia signaling is important for both horizontal (colony centre versus colony margin) and vertical (upper versus lower cell layers) colony differentiations. The centre of an aging differentiated giant colony is thus composed of two major cell subpopulations, the subpopulation of long-living, metabolically active and stress-resistant cells that form the upper layers of the colony and the subpopulation of stress-sensitive starving cells in the colony interior. Here, we show that microcolonies originating from one cell pass through similar developmental phases as giant colonies. Microcolony differentiation is linked to ammonia signaling, and cells similar to the upper and lower cells of aged giant colonies are formed even in relatively young microcolonies. A comparison of the properties of these cells revealed a number of features that are similar in microcolonies and giant colonies as well as a few that are only typical of chronologically aged giant colonies. These findings show that colony age per se is not crucial for colony differentiation. PMID:23970946

  14. Opposite differential risks for autism and schizophrenia based on maternal age, paternal age, and parental age differences

    PubMed Central

    Byars, Sean G.; Boomsma, Jacobus J.

    2016-01-01

    Background and objectives: Effects of maternal and paternal age on offspring autism and schizophrenia risks have been studied for over three decades, but inconsistent risks have often been found, precluding well-informed speculation on why these age-related risks might exist. Methodology: To help clarify this situation we analysed a massive single population sample from Denmark including the full spectrum of autistic and schizophrenic disorders (eliminating between-study confounding), used up to 30 follow-up years, controlled for over 20 potentially confounding factors and interpret the ultimate causation of the observed risk patterns using generally accepted principles of parent-offspring conflict and life-history theory. Results: We evaluated the effects of paternal age, maternal age and parental age difference on offspring mental disorders and found consistently similar risk patterns for related disorders and markedly different patterns between autistic and schizophrenic disorders. Older fathers and mothers both conferred increased risk for autistic but not schizophrenic disorders, but autism risk was reduced in younger parents and offspring of younger mothers had increased risk for many schizophrenic disorders. Risk for most disorders also increased when parents were more dissimilarly aged. Monotonically increasing autism risk is consistent with mutation accumulation as fathers’ age, but this explanation is invalid for schizophrenic disorders, which were not related to paternal age and were negatively correlated with maternal age. Conclusions and implications: We propose that the observed maternally induced risk patterns ultimately reflect a shifting ancestral life-history trade-off between current and future reproduction, mediated by an initially high but subsequently decreasing tendency to constrain foetal provisioning as women proceed from first to final pregnancy. PMID:27637201

  15. Language networks associated with computerized semantic indices.

    PubMed

    Pakhomov, Serguei V S; Jones, David T; Knopman, David S

    2015-01-01

    Tests of generative semantic verbal fluency are widely used to study organization and representation of concepts in the human brain. Previous studies demonstrated that clustering and switching behavior during verbal fluency tasks is supported by multiple brain mechanisms associated with semantic memory and executive control. Previous work relied on manual assessments of semantic relatedness between words and grouping of words into semantic clusters. We investigated a computational linguistic approach to measuring the strength of semantic relatedness between words based on latent semantic analysis of word co-occurrences in a subset of a large online encyclopedia. We computed semantic clustering indices and compared them to brain network connectivity measures obtained with task-free fMRI in a sample consisting of healthy participants and those differentially affected by cognitive impairment. We found that semantic clustering indices were associated with brain network connectivity in distinct areas including fronto-temporal, fronto-parietal and fusiform gyrus regions. This study shows that computerized semantic indices complement traditional assessments of verbal fluency to provide a more complete account of the relationship between brain and verbal behavior involved organization and retrieval of lexical information from memory.

  16. Age-dependent Wnt gene expression in bone and during the course of osteoblast differentiation

    PubMed Central

    Rauner, Martina; Sipos, Wolfgang

    2008-01-01

    Wnt signaling is vital for osteoblast differentiation and recently has been associated with aging. Because impaired osteoblastogenesis is a cellular characteristic of age-induced bone loss, we investigated whether this process is associated with an altered expression of Wnt signaling-related proteins in bone and osteoblasts. Bone marrow cells were isolated from male C57BL/6 mice, aged 6 weeks, 6 months, and 18 months, respectively. Osteogenic differentiation was induced for 3 weeks and assessed using alizarin red staining. Gene expression of Wnt1, 3a, 4, 5a, 5b, 7b, 9b, 10b, lipoprotein receptor-related protein (LRP)-5/6, as well as dickkopf-1 (Dkk-1), sclerostin, and secreted frizzled related protein-1 (sFRP-1) was determined in bone tissue and osteoblasts on days 7, 14, and 21 by real-time RT-PCR. Osteoblast differentiation was significantly reduced in aged mice compared with young and adult mice. In bone tissue, expression levels of all genes assessed were decreased in adult and old mice, respectively, compared with young mice. Mature osteoblasts of aged compared with those of young mice showed enhanced expression of Wnt9b, LRP-6, and Dkk-1, and decreased expression of Wnt5a and 7b. In early osteoblasts, mRNA levels of Wnt1, 5a, 5b, and 7b were increased significantly in aged mice. The expression of Wnt3a, 4, LRP-5, and sclerostin was not altered in aged osteoblasts. In conclusion, osteoblastic expression of each Wnt-related protein is regulated individually by aging. The overall decreased expression of Wnt-related proteins in bone tissue of aged mice underlines the newly discovered association of Wnt signaling with aging. PMID:19424851

  17. Early planetesimal melting from an age of 4.5662 Gyr for differentiated meteorites.

    PubMed

    Baker, Joel; Bizzarro, Martin; Wittig, Nadine; Connelly, James; Haack, Henning

    2005-08-25

    Long- and short-lived radioactive isotopes and their daughter products in meteorites are chronometers that can test models for Solar System formation. Differentiated meteorites come from parent bodies that were once molten and separated into metal cores and silicate mantles. Mineral ages for these meteorites, however, are typically younger than age constraints for planetesimal differentiation. Such young ages indicate that the energy required to melt their parent bodies could not have come from the most likely heat source-radioactive decay of short-lived nuclides ((26)Al and (60)Fe) injected from a nearby supernova-because these would have largely decayed by the time of melting. Here we report an age of 4.5662 +/- 0.0001 billion years (based on Pb-Pb dating) for basaltic angrites, which is only 1 Myr younger than the currently accepted minimum age of the Solar System and corresponds to a time when (26)Al and (60)Fe decay could have triggered planetesimal melting. Small (26)Mg excesses in bulk angrite samples confirm that (26)Al decay contributed to the melting of their parent body. These results indicate that the accretion of differentiated planetesimals pre-dated that of undifferentiated planetesimals, and reveals the minimum Solar System age to be 4.5695 +/- 0.0002 billion years.

  18. Phonological Differentiation before Age Two in a Tagalog-Spanish-English Trilingual Child

    ERIC Educational Resources Information Center

    Montanari, Simona

    2011-01-01

    This study focuses on a trilingual toddler's ability to differentiate her Tagalog, Spanish and English productions on phonological/phonetic grounds. Working within the articulatory phonology framework, the word-initial segments produced by the child in Tagalog, Spanish and English words at age 1;10 were narrowly transcribed by two researchers and…

  19. Stromal-epithelial interactions in aging and cancer: Senescent fibroblasts alter epithelial cell differentiation

    SciTech Connect

    Parrinello, Simona; Coppe, Jean-Philippe; Krtolica, Ana; Campisi, Judith

    2004-07-14

    Cellular senescence suppresses cancer by arresting cells at risk for malignant tumorigenesis. However, senescent cells also secrete molecules that can stimulate premalignant cells to proliferate and form tumors, suggesting the senescence response is antagonistically pleiotropic. We show that premalignant mammary epithelial cells exposed to senescent human fibroblasts in mice irreversibly lose differentiated properties, become invasive and undergo full malignant transformation. Moreover, using cultured mouse or human fibroblasts and non-malignant breast epithelial cells, we show that senescent fibroblasts disrupt epithelial alveolar morphogenesis, functional differentiation, and branching morphogenesis. Further, we identify MMP-3 as the major factor responsible for the effects of senescent fibroblasts on branching morphogenesis. Our findings support the idea that senescent cells contribute to age-related pathology, including cancer, and describe a new property of senescent fibroblasts--the ability to alter epithelial differentiation--that might also explain the loss of tissue function and organization that is a hallmark of aging.

  20. Preserved Musical Semantic Memory in Semantic Dementia

    PubMed Central

    Weinstein, Jessica; Koenig, Phyllis; Gunawardena, Delani; McMillan, Corey; Bonner, Michael; Grossman, Murray

    2012-01-01

    Objective To understand the scope of semantic impairment in semantic dementia. Design Case study. Setting Academic medical center. Patient A man with semantic dementia, as demonstrated by clinical, neuropsychological, and imaging studies. Main Outcome Measures Music performance and magnetic resonance imaging results. Results Despite profoundly impaired semantic memory for words and objects due to left temporal lobe atrophy, this semiprofessional musician was creative and expressive in demonstrating preserved musical knowledge. Conclusion Long-term representations of words and objects in semantic memory may be dissociated from meaningful knowledge in other domains, such as music. PMID:21320991

  1. Action semantics modulate action prediction.

    PubMed

    Springer, Anne; Prinz, Wolfgang

    2010-11-01

    Previous studies have demonstrated that action prediction involves an internal action simulation that runs time-locked to the real action. The present study replicates and extends these findings by indicating a real-time simulation process (Graf et al., 2007), which can be differentiated from a similarity-based evaluation of internal action representations. Moreover, results showed that action semantics modulate action prediction accuracy. The semantic effect was specified by the processing of action verbs and concrete nouns (Experiment 1) and, more specifically, by the dynamics described by action verbs (Experiment 2) and the speed described by the verbs (e.g., "to catch" vs. "to grasp" vs. "to stretch"; Experiment 3). These results propose a linkage between action simulation and action semantics as two yet unrelated domains, a view that coincides with a recent notion of a close link between motor processes and the understanding of action language.

  2. Towards finding the linkage between metabolic and age-related disorders using semantic gene data network analysis

    PubMed Central

    Uzzal Hossain, Mohammad; Zaffar Shibly, Abu; Md. Omar, Taimur; Tous Zohora, Fatama; Sara Santona, Umme; Hossain, Md. Jakir; Hosen Khoka, Md. Sadek; Ara Keya, Chaman; Salimullah, Md.

    2016-01-01

    A metabolic disorder (MD) occurs when the metabolic process is disturbed. This process is carried out by thousands of enzymes participating in numerous inter-dependent metabolic pathways. Critical biochemical reactions that involve the processing and transportation of carbohydrates, proteins and lipids are affected in metabolic diseases. Therefore, it is of interest to identify the common pathways of metabolic disorders by building protein-protein interactions (PPI) for network analysis. The molecular network linkages between MD and age related diseases (ARD) are intriguing. Hence, we created networks of protein-protein interactions that are related with MD and ARD using relevant known data in the public domain. The network analysis identified known MD associated proteins and predicted genes and or its products of ARD in common pathways. The genes in the common pathways were isolated from the network and further analyzed for their co-localization and shared domains. Thus, a model hypothesis is proposed using interaction networks that are linked between MD and ARD. This data even if less conclusive finds application in understanding the molecular mechanism of known diseases in relation to observed molecular events PMID:27212841

  3. Dissociated developmental trajectories for semantic and phonological false memories.

    PubMed

    Holliday, Robyn E; Weekes, Brendan S

    2006-07-01

    False recognition following presentation of semantically related and phonologically related word lists was evaluated in 8-, 11-, and 13-year-olds. Children heard lists of words that were either semantic (e.g., bed, rest, wake ...) or phonological associates (e.g., pole, bowl, hole ...) of a critical unpresented word (e.g., sleep, roll), respectively. A semantic false memory was defined as false recognition of a semantically related but unpresented word. A phonological false memory was defined as false recognition of a phonologically related but unpresented word. False memories in the two tasks showed opposite developmental trends, increasing with age for semantic relatedness and decreasing with age for phonological relatedness.

  4. Differentiating selves: middle-aged gay men in Manchester's less visible 'homospaces'.

    PubMed

    Simpson, Paul

    2014-03-01

    Scholarship on gay bars/'villages' has overshadowed study of 'homospaces' (gay fields of existence) less available/inaccessible to a wider public - websites, saunas and social/support groups. Based on interviews with 27 men aged 39-61 living in Manchester, this article addresses what middle-aged gay men's accounts of these particular homospaces say about their experiences of age/ageing and how relations of ageism work within them. Specifically, I focus on how study participants use 'ageing capital' in these fields to differentiate themselves from their younger counterparts in three ways. First, ageing capital is implicated in capitulation to gay ageism and a reverse ageism - visible in accounts of differentiation from the 'superficial,' reckless ways of sexualized space that participants associated with younger gay men. Second, it was visible in accounts of resistance to/questioning of gay ageism - strategies that could make sexualized homospaces more habitable. Third, ageing capital was implicated in negotiation with ageing/gay ageism - visible in ambivalent stances hovering between compliance and resistance - towards ageing and ageism, which could reinforce constraints on uses/display of the body. The first and third accounts indicate the multidirectional character of gay ageism, limits on the deployment on ageing capital and show how middle-aged men can undermine their generational claims to represent a more authentic form of gay male embodiment. En route, I also complicate stereotypical thinking that gay social/support groups represent more inclusive, empowering space whilst overtly sexualized spaces of the 'gay scene' represent the opposite.

  5. Effects of strength training on osteogenic differentiation and bone strength in aging female Wistar rats

    PubMed Central

    Singulani, Monique Patricio; Stringhetta-Garcia, Camila Tami; Santos, Leandro Figueiredo; Morais, Samuel Rodrigues Lourenço; Louzada, Mário Jefferson Quirino; Oliveira, Sandra Helena Penha; Chaves Neto, Antonio Hernandes; Dornelles, Rita Cássia Menegati

    2017-01-01

    The effects of strength training (ST) on the mechanical bone strength and osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) from adult, aged and exercised aged rats were determined. The exercised aged animals displayed higher values of areal bone mineral density, compression test, alkaline phosphatase activity (ALP) and biological mineralization, while oil red O staining for adipocytes was lower. ST increased gene expression of runt-related transcription factor 2 (Runx2), osterix (Osx) as well as bone matrix protein expression, and reduced expression of peroxisome proliferator-activated receptor gamma (Pparγ). The production of pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α) was lower in BMSCs of the aged exercised group. The ST practice was able to improve the bone mechanical properties in aged female rats, increasing the potential for osteogenic differentiation of BMSCs, reducing the adipogenic differentiation and pro-inflammatory cytokine level. In summary, the data achieved in this study showed that strength training triggers physiological responses that result in changes in the bone microenvironment and bring benefits to biomechanical parameters of bone tissue, which could reduce the risk of fractures during senescent. PMID:28211481

  6. Effects of strength training on osteogenic differentiation and bone strength in aging female Wistar rats.

    PubMed

    Singulani, Monique Patricio; Stringhetta-Garcia, Camila Tami; Santos, Leandro Figueiredo; Morais, Samuel Rodrigues Lourenço; Louzada, Mário Jefferson Quirino; Oliveira, Sandra Helena Penha; Chaves Neto, Antonio Hernandes; Dornelles, Rita Cássia Menegati

    2017-02-17

    The effects of strength training (ST) on the mechanical bone strength and osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) from adult, aged and exercised aged rats were determined. The exercised aged animals displayed higher values of areal bone mineral density, compression test, alkaline phosphatase activity (ALP) and biological mineralization, while oil red O staining for adipocytes was lower. ST increased gene expression of runt-related transcription factor 2 (Runx2), osterix (Osx) as well as bone matrix protein expression, and reduced expression of peroxisome proliferator-activated receptor gamma (Pparγ). The production of pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α) was lower in BMSCs of the aged exercised group. The ST practice was able to improve the bone mechanical properties in aged female rats, increasing the potential for osteogenic differentiation of BMSCs, reducing the adipogenic differentiation and pro-inflammatory cytokine level. In summary, the data achieved in this study showed that strength training triggers physiological responses that result in changes in the bone microenvironment and bring benefits to biomechanical parameters of bone tissue, which could reduce the risk of fractures during senescent.

  7. Human actuarial aging increases faster when background death rates are lower: a consequence of differential heterogeneity?

    PubMed

    Hawkes, Kristen; Smith, Ken R; Blevins, James K

    2012-01-01

    Many analyses of human populations have found that age-specific mortality rates increase faster across most of adulthood when overall mortality levels decline. This contradicts the relationship often expected from Williams' classic hypothesis about the effects of natural selection on the evolution of senescence. More likely, much of the within-species difference in actuarial aging is not due to variation in senescence, but to the strength of filters on the heterogeneity of frailty in older survivors. A challenge to this differential frailty hypothesis was recently posed by an analysis of life tables from historical European populations and traditional societies that reported variation in actuarial aging consistent with Williams' hypothesis after all. To investigate the challenge, we reconsidered those cases and aging measures. Here we show that the discrepancy depends on Ricklefs' aging rate measure, ω, which decreases as mortality levels drop because it is an index of mortality level itself, not the rate of increase in mortality with age. We also show unappreciated correspondence among the parameters of Gompertz-Makeham and Weibull survival models. Finally, we compare the relationships among mortality parameters of the traditional societies and the historical series, providing further suggestive evidence that differential heterogeneity has strong effects on actuarial aging.

  8. Ageing and muscular dystrophy differentially affect murine pharyngeal muscles in a region-dependent manner

    PubMed Central

    Randolph, Matthew E; Luo, Qingwei; Ho, Justin; Vest, Katherine E; Sokoloff, Alan J; Pavlath, Grace K

    2014-01-01

    The inability to swallow, or dysphagia, is a debilitating and life-threatening condition that arises with ageing or disease. Dysphagia results from neurological or muscular impairment of one or more pharyngeal muscles, which function together to ensure proper swallowing and prevent the aspiration of food or liquid into the lungs. Little is known about the effects of age or disease on pharyngeal muscles as a group. Here we show ageing affected pharyngeal muscle growth and atrophy in wild-type mice depending on the particular muscle analysed. Furthermore, wild-type mice also developed dysphagia with ageing. Additionally, we studied pharyngeal muscles in a mouse model for oculopharyngeal muscular dystrophy, a dysphagic disease caused by a polyalanine expansion in the RNA binding protein, PABPN1. We examined pharyngeal muscles of mice overexpressing either wild-type A10 or mutant A17 PABPN1. Overexpression of mutant A17 PABPN1 differentially affected growth of the palatopharyngeus muscle dependent on its location within the pharynx. Interestingly, overexpression of wild-type A10 PABPN1 was protective against age-related muscle atrophy in the laryngopharynx and prevented the development of age-related dysphagia. These results demonstrate that pharyngeal muscles are differentially affected by both ageing and muscular dystrophy in a region-dependent manner. These studies lay important groundwork for understanding the molecular and cellular mechanisms that regulate pharyngeal muscle growth and atrophy, which may lead to novel therapies for individuals with dysphagia. PMID:25326455

  9. Aging and differentiation in yeast populations: elders with different properties and functions.

    PubMed

    Palková, Zdena; Wilkinson, Derek; Váchová, Libuše

    2014-02-01

    Over the past decade, it has become evident that similarly to cells forming metazoan tissues, yeast cells have the ability to differentiate and form specialized cell types. Examples of yeast cellular differentiation have been identified both in yeast liquid cultures and within multicellular structures occupying solid surfaces. Most current knowledge on different cell types comes from studies of the spatiotemporal internal architecture of colonies developing on various media. With a few exceptions, yeast cell differentiation often concerns nongrowing, stationary-phase cells and leads to the formation of cell subpopulations differing in stress resistance, cell metabolism, respiration, ROS production, and others. These differences can affect longevity of particular subpopulations. In contrast to liquid cultures, where various cell types are dispersed within stationary-phase populations, cellular differentiation depends on the specific position of particular cells within multicellular colonies. Differentiated colonies, thus, resemble primitive multicellular organisms, in which the gradients of certain compounds and the position of cells within the structure affect cellular differentiation. In this review, we summarize and compare the properties of diverse types of differentiated chronologically aging yeast cells that have been identified in colonies growing on different media, as well as of those found in liquid cultures.

  10. IGF-1 Receptor Insufficiency Leads to Age-Dependent Attenuation of Osteoblast Differentiation

    PubMed Central

    Yeh, Lee-Chuan C.; Wilkerson, Matthew; Lee, John C.

    2015-01-01

    In the current study, we determined the effects of IGF-1 receptor haploinsufficiency on osteoblast differentiation and bone formation throughout the lifespan. Bone mineral density was significantly decreased in femurs of male and female Igf1r+/− mice compared with wild-type mice. mRNA expression of osteoblast differentiation markers was significantly decreased in femurs and calvariae from Igf1r+/− mice compared with cells from wild-type mice. Bone morphogenetic protein-7-induced ectopic bone in Igf1r+/− mice was significantly smaller with fewer osteoblasts but more lipid droplets and had reduced expression of osteoblast differentiation markers compared with wild-type mice. In bone marrow cells from middle-aged and old wild-type and Igf1r+/− male mice, palmitate inhibited osteoblast markers expression. In cells from young wild-type male mice, palmitate did not inhibit marker expression, but in cells from young male Igf1r+/− mice, palmitate inhibited bone sialoprotein and osterix but not osteocalcin or type I collagen (TIC). In female wild-type mice, palmitate inhibited osteoblast markers expression in cells from young, middle-aged, and old mice except TIC in cells from middle-aged mice. Palmitate inhibited bone sialoprotein expression in cells from middle-aged and old female Igf1r+/− mice and osteocalcin, osterix, and TIC expression in young and middle-aged female Igf1r+/− mice but stimulated expression in cells from old female Igf1r+/− mice. We conclude that IGF-1 receptor haploinsufficiency results in a prolipid accrual phenotype in bone in association with inhibition of growth factor-induced osteoblast differentiation, a situation which may phenocopy age-related decreases in bone formation. PMID:26076041

  11. Aging and insulin signaling differentially control normal and tumorous germline stem cells.

    PubMed

    Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

    2015-02-01

    Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC-male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging.

  12. Aging and insulin signaling differentially control normal and tumorous germline stem cells

    PubMed Central

    Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

    2015-01-01

    Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC–male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging. PMID:25470527

  13. The Trend of Age-Group Effect on Prognosis in Differentiated Thyroid Cancer.

    PubMed

    Shi, Rong-Liang; Qu, Ning; Liao, Tian; Wei, Wen-Jun; Wang, Yu-Long; Ji, Qing-Hai

    2016-06-08

    Age has been included in various prognostic scoring systems for differentiated thyroid cancer (DTC). The aim of this study is to re-examine the relationship between age and prognosis by using Surveillance, Epidemiology, and End Results (SEER) population-based database. We identified 51,061 DTC patients between 2004 and 2012. Patients were separated into 10-year age groups. Cancer cause-specific survival (CSS) and overall survival (OS) data were obtained. Kaplan-Meier and multivariable Cox models were built to analyze the outcomes and risk factors. Increasing age gradient with a 10-year interval was associated with the trend of higher proportions for male gender, grade III/IV and summary stage of distant metastases. Both CSS and OS continued to worsen with increasing age, being poorest in in the oldest age group (≥71); multivariate analysis confirmed that CSS continued to fall with each age decade, significantly starting at 60 years (HR = 7.5, 95% 1.0-54.1, p = 0.047) compared to the young group (≤20). Similarly, multivariate analysis suggested that OS continued worsening with increasing age, but starting at 40 years (HR = 3.7, 95% 1.4-10.1, p = 0.009) compared to the young group. The current study suggests that an age exceeding 60 years itself represents an unfavorable prognostic factor and high risk for cancer-specific death in DTC.

  14. Instrumental analysis for differentiation of beers and evaluation of beer ageing

    NASA Astrophysics Data System (ADS)

    Dreve, Simina; Voica, Cezara; Dragan, Felicia; Georgiu, Monica

    2013-11-01

    A representative selection of 5 different beers commercially available were measured spectrophotometrically in UV-Vis spectral region and by fluorescence spectroscopy, in order to determine qualitative differentiation due to the mainly iso-R-acids (with a five member ring) originating from R-acids present in hops. Minerals and trace elements analysis were also performed by ICP-MS method. The determination of the bitter organic acids in beers and of the content in metallic ions can be used as indicators for differentiation of beers and evaluation of beer ageing.

  15. Elucidating semantic disorganisation from a word comprehension task: do patients with schizophrenia and bipolar disorder show differential processing of nouns, verbs and adjectives?

    PubMed

    Rossell, Susan L; Batty, Rachel A

    2008-07-01

    Memory deficits have been reported in schizophrenia and bipolar disorder. However, the precise impact of semantic memory deficits on word comprehension, particularly across grammatical categories, has not been adequately investigated in these disorders. Furthermore, previous studies examining semantic memory have predominantly been designed so that most healthy controls perform at ceiling, questioning the validity of observed differences between patient and control groups. A new word definition task examined word comprehension across grammatical categories, i.e. nouns, verbs and adjectives, and was designed to overcome the ceiling effect. It was administered to 32 schizophrenia patients, 28 bipolar disorder patients and 32 matched healthy controls. Schizophrenia patients had a global impairment on the task but bipolar patients were only impaired on a recognition memory component. Word comprehension, however, across grammatical categories was comparable across groups.

  16. Patterns of anxiety symptoms in toddlers and preschool-age children: evidence of early differentiation.

    PubMed

    Mian, Nicholas D; Godoy, Leandra; Briggs-Gowan, Margaret J; Carter, Alice S

    2012-01-01

    The degree to which young children's anxiety symptoms differentiate according to diagnostic groupings is under-studied, especially in children below the age of 4 years. Theoretical (confirmatory factor analysis, CFA) and statistical (exploratory factor analysis, EFA) analytical methods were employed to test the hypothesis that anxiety symptoms among 2-3-year-old children from a non-clinical, representative sample would differentiate in a manner consistent with current diagnostic nosology. Anxiety symptom items were selected from two norm-referenced parent-report scales of child behavior. CFA and EFA results suggested that anxiety symptoms aggregate in a manner consistent with generalized anxiety, obsessive-compulsive symptoms, separation anxiety, and social phobia. Multi-dimensional models achieved good model fit and fit the data significantly better than undifferentiated models. Results from EFA and CFA methods were predominantly consistent and supported the grouping of early childhood anxiety symptoms into differentiated, diagnostic-specific categories.

  17. Deriving age-specific incidence from prevalence with an ordinary differential equation.

    PubMed

    Brinks, Ralph; Landwehr, Sandra; Icks, Andrea; Koch, Michael; Giani, Guido

    2013-05-30

    This article describes new relationships between the age-specific incidence of, the prevalence of and mortality from a chronic disease. We express these relationships in terms of an ordinary differential equation and form the methodological basis for a novel approach to estimating incidences from age-specific prevalence data. We examine practical aspects of the relationships and a comparison with a known stochastic method in a simulation study. Finally, we apply the novel method to a data set of renal replacement therapy recorded from patients with chronic kidney failure in a region of Germany with approximately 310,000 inhabitants from 2002 to 2010.

  18. Further differentiating item and order information in semantic memory: students' recall of words from the "CU Fight Song", Harry Potter book titles, and Scooby Doo theme song.

    PubMed

    Overstreet, Michael F; Healy, Alice F; Neath, Ian

    2017-01-01

    University of Colorado (CU) students were tested for both order and item information in their semantic memory for the "CU Fight Song". Following an earlier study by Overstreet and Healy [(2011). Item and order information in semantic memory: Students' retention of the "CU fight song" lyrics. Memory & Cognition, 39, 251-259. doi: 10.3758/s13421-010-0018-3 ], a symmetrical bow-shaped serial position function (with both primacy and recency advantages) was found for reconstructing the order of the nine lines in the song, whereas a function with no primacy advantage was found for recalling a missing word from each line. This difference between order and item information was found even though students filled in missing words without any alternatives provided and missing words came from the beginning, middle, or end of each line. Similar results were found for CU students' recall of the sequence of Harry Potter book titles and the lyrics of the Scooby Doo theme song. These findings strengthen the claim that the pronounced serial position function in semantic memory occurs largely because of the retention of order, rather than item, information.

  19. Episodic, but not semantic, autobiographical memory is reduced in amnestic mild cognitive impairment

    PubMed Central

    Murphy, Kelly J.; Troyer, Angela K.; Levine, Brian; Moscovitch, Morris

    2008-01-01

    Amnestic mild cognitive impairment (aMCI) is characterized by decline in anterograde memory as measured by the ability to learn and remember new information. We investigated whether retrograde memory for autobiographical information was affected by aMCI. Eighteen control (age 66–84 years) and 17 aMCI (age 66–84 years) participants described a personal event from each of five periods across the lifespan. These events were transcribed and scored according to procedures that separate episodic (specific happenings) from semantic (general knowledge) elements of autobiographical memory. Although both groups generated protocols of similar length, the composition of autobiographical recall differentiated the groups. The aMCI group protocols were characterized by reduced episodic and increased semantic information relative to the control group. Both groups showed a similar pattern of recall across time periods, with no evidence that the aMCI group had more difficulty recalling recent, rather than remote, life events. These results indicate that episodic and semantic autobiographical memories are differentially affected by the early brain changes associated with aMCI. Reduced autobiographical episodic memories in aMCI may be the result of medial-temporal-lobe dysfunction, consistent with multiple trace theory, or alternatively, could be related to dysfunction of a wider related network of neocortical structures. In contrast, the preservation of autobiographical semantic memories in aMCI suggests neural systems, such as lateral temporal cortex, that support these memories, may remain relatively intact. PMID:18675285

  20. Donor age of human platelet lysate affects proliferation and differentiation of mesenchymal stem cells.

    PubMed

    Lohmann, Michael; Walenda, Gudrun; Hemeda, Hatim; Joussen, Sylvia; Drescher, Wolf; Jockenhoevel, Stefan; Hutschenreuter, Gabriele; Zenke, Martin; Wagner, Wolfgang

    2012-01-01

    The regenerative potential declines upon aging. This might be due to cell-intrinsic changes in stem and progenitor cells or to influences by the microenvironment. Mesenchymal stem cells (MSC) raise high hopes in regenerative medicine. They are usually culture expanded in media with fetal calf serum (FCS) or other serum supplements such as human platelet lysate (HPL). In this study, we have analyzed the impact of HPL-donor age on culture expansion. 31 single donor derived HPLs (25 to 57 years old) were simultaneously compared for culture of MSC. Proliferation of MSC did not reveal a clear association with platelet counts of HPL donors or growth factors concentrations (PDGF-AB, TGF-β1, bFGF, or IGF-1), but it was significantly higher with HPLs from younger donors (<35 years) as compared to older donors (>45 years). Furthermore, HPLs from older donors increased activity of senescence-associated beta-galactosidase (SA-βgal). HPL-donor age did not affect the fibroblastoid colony-forming unit (CFU-f) frequency, immunophenotype or induction of adipogenic differentiation, whereas osteogenic differentiation was significantly lower with HPLs from older donors. Concentrations of various growth factors (PDGF-AB, TGF-β1, bFGF, IGF-1) or hormones (estradiol, parathormone, leptin, 1,25 vitamin D3) were not associated with HPL-donor age or MSC growth. Taken together, our data support the notion that aging is associated with systemic feedback mechanisms acting on stem and progenitor cells, and this is also relevant for serum supplements in cell culture: HPLs derived from younger donors facilitate enhanced expansion and more pronounced osteogenic differentiation.

  1. Differential effects of Cytomegalovirus carriage on the immune phenotype of middle-aged males and females.

    PubMed

    van der Heiden, Marieke; van Zelm, Menno C; Bartol, Sophinus J W; de Rond, Lia G H; Berbers, Guy A M; Boots, Annemieke M H; Buisman, Anne-Marie

    2016-05-31

    The elderly population is more susceptible to infections as a result of an altered immune response, commonly referred to as immunosenescence. Cytomegalovirus (CMV)-infection associated changes in blood lymphocytes are known to impact this process, but the interaction with gender remains unclear. Therefore, we analysed the effects and interaction of gender and CMV on the absolute numbers of a comprehensive set of naive and memory T- and B-cell subsets in people between 50 and 65 years of age. Enumeration and characterisation of lymphocyte subsets by flow cytometry was performed on fresh whole blood samples from 255 middle-aged persons. CMV-IgG serostatus was determined by ELISA. Gender was a major factor affecting immune cell numbers. CMV infection was mainly associated with an expansion of late-differentiated T-cell subsets. CMV+ males carried lower numbers of total CD4+, CD4+ central memory (CM) and follicular helper T-cells than females and CMV- males. Moreover, CMV+ males had significantly lower numbers of regulatory T (Treg)-cells and memory B-cells than CMV+ females. We here demonstrate an interaction between the effects of CMV infection and gender on T- and B-cells in middle-aged individuals. These differential effects on adaptive immunity between males and females may have implications for vaccination strategies at middle-age.

  2. Differential effects of Cytomegalovirus carriage on the immune phenotype of middle-aged males and females

    PubMed Central

    van der Heiden, Marieke; van Zelm, Menno C.; Bartol, Sophinus J. W.; de Rond, Lia G. H.; Berbers, Guy A. M.; Boots, Annemieke M. H.; Buisman, Anne-Marie

    2016-01-01

    The elderly population is more susceptible to infections as a result of an altered immune response, commonly referred to as immunosenescence. Cytomegalovirus (CMV)-infection associated changes in blood lymphocytes are known to impact this process, but the interaction with gender remains unclear. Therefore, we analysed the effects and interaction of gender and CMV on the absolute numbers of a comprehensive set of naive and memory T- and B-cell subsets in people between 50 and 65 years of age. Enumeration and characterisation of lymphocyte subsets by flow cytometry was performed on fresh whole blood samples from 255 middle-aged persons. CMV-IgG serostatus was determined by ELISA. Gender was a major factor affecting immune cell numbers. CMV infection was mainly associated with an expansion of late-differentiated T-cell subsets. CMV+ males carried lower numbers of total CD4+, CD4+ central memory (CM) and follicular helper T-cells than females and CMV− males. Moreover, CMV+ males had significantly lower numbers of regulatory T (Treg)-cells and memory B-cells than CMV+ females. We here demonstrate an interaction between the effects of CMV infection and gender on T- and B-cells in middle-aged individuals. These differential effects on adaptive immunity between males and females may have implications for vaccination strategies at middle-age. PMID:27243552

  3. Aging impairs osteoblast differentiation of mesenchymal stem cells grown on titanium by favoring adipogenesis

    PubMed Central

    ABUNA, Rodrigo Paolo Flores; STRINGHETTA-GARCIA, Camila Tami; FIORI, Leonardo Pimentel; DORNELLES, Rita Cassia Menegati; ROSA, Adalberto Luiz; BELOTI, Marcio Mateus

    2016-01-01

    ABSTRACT Aging negatively affects bone/titanium implant interactions. Our hypothesis is that the unbalance between osteogenesis and adipogenesis induced by aging may be involved in this phenomenon. Objective We investigated the osteoblast and adipocyte differentiation of mesenchymal stem cells (MSCs) from young and aged rats cultured on Ti. Material and Methods Bone marrow MSCs derived from 1-month and 21-month rats were cultured on Ti discs under osteogenic conditions for periods of up to 21 days and osteoblast and adipocyte markers were evaluated. Results Cell proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization and gene expression of RUNX2, osterix, ALP, bone sialoprotein, osteopontin, and osteocalcin were reduced in cultures of 21-month rats compared with 1-month rats grown on Ti. Gene expression of PPAR-γ , adipocyte protein 2, and resistin and lipid accumulation were increased in cultures of 21-month rats compared with 1-month rats grown on the same conditions. Conclusions These results indicate that the lower osteogenic potential of MSCs derived from aged rats compared with young rats goes along with the higher adipogenic potential in cultures grown on Ti surface. This unbalance between osteoblast and adipocyte differentiation should be considered in dental implant therapy to the elderly population. PMID:27556209

  4. Differential response to intrahippocampal interleukin-4/interleukin-13 in aged and exercise mice.

    PubMed

    Littlefield, Alyssa; Kohman, Rachel A

    2017-02-20

    Normal aging is associated with low-grade neuroinflammation that results from age-related priming of microglial cells. Further, aging alters the response to several anti-inflammatory factors, including interleukin (IL)-4 and IL-13. One intervention that has been shown to modulate microglia activation in the aged brain, both basally and following an immune challenge, is exercise. However, whether engaging in exercise can improve responsiveness to anti-inflammatory cytokines is presently unknown. The current study evaluated whether prior exercise training increases sensitivity to anti-inflammatory cytokines that promote the M2 (alternative) microglia phenotype in adult (5-month-old) and aged (23-month-old) C57BL/6J mice. After 8weeks of exercise or control housing, mice received bilateral hippocampal injections of an IL-4/IL-13 cocktail or vehicle. Twenty-four hours later hippocampal samples were collected and analyzed for expression of genes associated with the M1 (inflammatory) and M2 microglia phenotypes. Results show that IL-4/IL-13 administration increased expression of the M2-associated genes found in inflammatory zone 1 (Fizz1), chitinase-like 3 (Ym1), Arginase-1 (Arg1), SOCS1, IL-1ra, and CD206. In response to IL-4/IL-13 administration, aged mice showed increased hippocampal expression of the M2-related genes Arg1, SOCS1, Ym1, and CD206 relative to adult mice. Aged mice also showed increased expression of IL-1β relative to adults, which was unaffected by wheel running or IL-4/IL-13. Wheel running was found to have modest effects on expression of Ym1 and Fizz1 in aged and adult mice. Collectively, our findings indicate that aged mice show a differential response to anti-inflammatory cytokines relative to adult mice and that exercise has limited effects on modulating this response.

  5. Aging differentially affects male and female neural stem cell neurogenic properties

    PubMed Central

    Waldron, Jay; McCourty, Althea; Lecanu, Laurent

    2010-01-01

    Purpose Neural stem cell transplantation as a brain repair strategy is a very promising technology. However, despite many attempts, the clinical success remains very deceiving. Despite clear evidence that sexual dimorphism rules many aspects of human biology, the occurrence of a sex difference in neural stem cell biology is largely understudied. Herein, we propose to determine whether gender is a dimension that drives the fate of neural stem cells through aging. Should it occur, we believe that neural stem cell sexual dimorphism and its variation during aging should be taken into account to refine clinical approaches of brain repair strategies. Methods Neural stem cells were isolated from the subventricular zone of three- and 20-month-old male and female Long-Evans rats. Expression of the estrogen receptors, ERα and ERβ, progesterone receptor, androgen receptor, and glucocorticoid receptor was analyzed and quantified by Western blotting on undifferentiated neural stem cells. A second set of neural stem cells was treated with retinoic acid to trigger differentiation, and the expression of neuronal, astroglial, and oligodendroglial markers was determined using Western blotting. Conclusion We provided in vitro evidence that the fate of neural stem cells is affected by sex and aging. Indeed, young male neural stem cells mainly expressed markers of neuronal and oligodendroglial fate, whereas young female neural stem cells underwent differentiation towards an astroglial phenotype. Aging resulted in a lessened capacity to express neuron and astrocyte markers. Undifferentiated neural stem cells displayed sexual dimorphism in the expression of steroid receptors, in particular ERα and ERβ, and the expression level of several steroid receptors increased during aging. Such sexual dimorphism might explain, at least in part, the sex difference in neural fate we observed in young and old neural stem cells. These results suggest that sex and aging are two factors to be taken

  6. Feature type effects in semantic memory: an event related potentials study.

    PubMed

    Sartori, Giuseppe; Polezzi, David; Mameli, Francesca; Lombardi, Luigi

    2005-12-30

    It is believed that the N400 elicited by concepts belonging to Living things is larger than the N400 to Non-living things. This is considered as evidence that concepts are organized, in the brain, on the basis of categories. Similarly, differential N400 to Sensory and Non-sensory semantic features is taken as evidence for a neural organisation of conceptual memory based on semantic features. We conducted a feature-verification experiment where Living and Non-living concepts are described by Sensory and Non-sensory features and were matched for Age-of-Acquisition, typicality and familiarity and finally for relevance of semantic features. Relevance is a measure of the contribution of semantic features to the "core" meaning of a concept. We found that when Relevance is low then the N400 is large. In addition, we found that when the two categories of Living and Non-living concepts are matched for relevance the seemingly category effect at the neural level disappeared. Also no difference between Sensory and Non-sensory descriptions was detected when relevance was matched. In sum, N400 does not differ between categories or feature types. Previously reported effects of semantic categories and feature type may have arisen as a consequence of the differing Relevance of concepts belonging to Living and Non-living categories.

  7. Semantics via Machine Translation

    ERIC Educational Resources Information Center

    Culhane, P. T.

    1977-01-01

    Recent experiments in machine translation have given the semantic elements of collocation in Russian more objective criteria. Soviet linguists in search of semantic relationships have attempted to devise a semantic synthesis for construction of a basic language for machine translation. One such effort is summarized. (CHK)

  8. Research on Individualized Product Requirement Expression Based on Semantic Network

    NASA Astrophysics Data System (ADS)

    Yang, Qin; Pan, Xiuqin; Wei, Daozhu; Wu, Ke

    In order to establish an effective platform for individualized product development, the individualized product requirement expression forms were put forward. The diversity Semantic Network of product knowledge representation was researched based on the dualistic semantic network, and the product requirement framework model was established. Thereby the validity, reliability and consistency of the requirement expression process were ensured. Finally an example of customer requirement expression model about differential mechanism based on semantic network was described to satisfy with the individualized product design system.

  9. Snapshots of Children's Changing Biases during Language Development: Differential Weighting of Perceptual and Linguistic Factors Predicts Noun Age of Acquisition

    ERIC Educational Resources Information Center

    Ramey, Christopher H.; Chrysikou, Evangelia G.; Reilly, Jamie

    2013-01-01

    Word learning is a lifelong activity constrained by cognitive biases that people possess at particular points in development. Age of acquisition (AoA) is a psycholinguistic variable that may prove useful toward gauging the relative weighting of different phonological, semantic, and morphological factors at different phases of language acquisition…

  10. Differential peptidomics assessment of strain and age differences in mice in response to acute cocaine administration.

    PubMed

    Romanova, Elena V; Rubakhin, Stanislav S; Ossyra, John R; Zombeck, Jonathan A; Nosek, Michael R; Sweedler, Jonathan V; Rhodes, Justin S

    2015-12-01

    Neurochemical differences in the hypothalamic-pituitary axis between individuals and between ages may contribute to differential susceptibility to cocaine abuse. This study measured peptide levels in the pituitary gland (Pit) and lateral hypothalamus (LH) in adolescent (age 30 days) and adult (age 65 days) mice from four standard inbred strains, FVB/NJ, DBA/2J, C57BL/6J, and BALB/cByJ, which have previously been characterized for acute locomotor responses to cocaine. Individual peptide profiles were analyzed using mass spectrometric profiling and principal component analysis. Sequences of assigned peptides were verified by tandem mass spectrometry. Principal component analysis classified all strains according to their distinct peptide profiles in Pit samples from adolescent mice, but not adults. Select pro-opiomelanocortin-derived peptides were significantly higher in adolescent BALB/cByJ and DBA/2J mice than in FVB/NJ or C57BL/6J mice. A subset of peptides in the LH, but not in the Pit, was altered by cocaine in adolescents. A 15 mg/kg dose of cocaine induced greater peptide alterations than a 30 mg/kg dose, particularly in FVB/NJ animals, with larger differences in adolescents than adults. Neuropeptides in the LH affected by acute cocaine administration included pro-opiomelanocortin-, myelin basic protein-, and glutamate transporter-derived peptides. The observed peptide differences could contribute to differential behavioral sensitivity to cocaine among strains and ages. Peptides were measured using mass spectrometry (MALDI-TOF) in individual lateral hypothalamus and pituitary samples from four strains and two ages of inbred mice in response to acute cocaine administration. Principal component analyses (PCA) classified the strains according to their peptide profiles from adolescent mice, and a subset of peptides in the lateral hypothalamus was altered by cocaine in adolescents.

  11. Differentiation rather than aging of muscle stem cells abolishes their telomerase activity

    PubMed Central

    O’Connor, Matthew S.; Carlson, Morgan E.; Conboy, Irina M.

    2009-01-01

    A general feature of stem cells is the ability to routinely proliferate in order to build, maintain, and repair organ systems. Accordingly, embryonic and germline, as well as some adult stem cells, produce the telomerase enzyme at various levels of expression. Our results show that, while muscle is a largely post-mitotic tissue, the muscle stem cells (satellite cells) that maintain this biological system throughout adult life do indeed display robust telomerase activity. Conversely, primary myoblasts (the immediate progeny of satellite cells) quickly and dramatically down-regulate telomerase activity. This work thus suggests that satellite cells, and early transient myoblasts, may be more promising therapeutic candidates for regenerative medicine than traditionally utilized myoblast cultures. Muscle atrophy accompanies human aging, and satellite cells endogenous to aged muscle can be triggered to regenerate old tissue by exogenous molecular cues. Therefore, we also examined whether these aged muscle stem cells would produce tissue that is “young” with respect to telomere maintenance. Interestingly, this work shows that the telomerase activity in muscle stem cells is largely retained into old age wintin inbred “long” telomere mice and in wild-derived short telomere mouse strains, and that age-specific telomere shortening is undetectable in the old differentiated muscle fibers of either strain. Summarily, this work establishes that young and old muscle stem cells, but not necessarily their progeny, myoblasts, are likely to produce tissue with normal telomere maintenance when used in molecular and regenerative medicine approaches for tissue repair. PMID:19455648

  12. In-vivo differentiation of photo-aged epidermis skin by texture-based classification

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoman; Weng, Cuncheng; Yu, Biying; Li, Hui

    2014-11-01

    Two sets of in vivo female cheek skin epidermis images were analyzed through gray level co-occurrence matrix (GLCM) and fast fourier transform (FFT). One set was derived from women in their 20s and the other from women more than 60 years of age. GLCM was used to evaluate the texture features of the regions of interest within the cheek epidermis, and texture classification was subsequently performed. During texture classification, 25 images (320×240 pixels) in each age set were randomly selected. Three texture features, i.e., energy, contrast, and correlation, were obtained from the skin images and analyzed at four orientations (0°, 45°,90°, and 135°), accompanied by different distances between two pixels. The textures of the different aging skins were characterized by FFT, which provides the dermatoglyph orientation index. The differences in the textures between the young and old skin samples can be well described by the FFT dermatoglyph orientation index. The texture features varied among the different aging skins, which provide a versatile platform for differentiating the statuses of aging skins.

  13. Modelling T cell proliferation: Dynamics heterogeneity depending on cell differentiation, age, and genetic background

    PubMed Central

    2017-01-01

    Cell proliferation is the common characteristic of all biological systems. The immune system insures the maintenance of body integrity on the basis of a continuous production of diversified T lymphocytes in the thymus. This involves processes of proliferation, differentiation, selection, death and migration of lymphocytes to peripheral tissues, where proliferation also occurs upon antigen recognition. Quantification of cell proliferation dynamics requires specific experimental methods and mathematical modelling. Here, we assess the impact of genetics and aging on the immune system by investigating the dynamics of proliferation of T lymphocytes across their differentiation through thymus and spleen in mice. Our investigation is based on single-cell multicolour flow cytometry analysis revealing the active incorporation of a thymidine analogue during S phase after pulse-chase-pulse experiments in vivo, versus cell DNA content. A generic mathematical model of state transition simulates through Ordinary Differential Equations (ODEs) the evolution of single cell behaviour during various durations of labelling. It allows us to fit our data, to deduce proliferation rates and estimate cell cycle durations in sub-populations. Our model is simple and flexible and is validated with other durations of pulse/chase experiments. Our results reveal that T cell proliferation is highly heterogeneous but with a specific “signature” that depends upon genetic origins, is specific to cell differentiation stages in thymus and spleen and is altered with age. In conclusion, our model allows us to infer proliferation rates and cell cycle phase durations from complex experimental 5-ethynyl-2'-deoxyuridine (EdU) data, revealing T cell proliferation heterogeneity and specific signatures. PMID:28288157

  14. Modelling T cell proliferation: Dynamics heterogeneity depending on cell differentiation, age, and genetic background.

    PubMed

    Vibert, Julien; Thomas-Vaslin, Véronique

    2017-03-01

    Cell proliferation is the common characteristic of all biological systems. The immune system insures the maintenance of body integrity on the basis of a continuous production of diversified T lymphocytes in the thymus. This involves processes of proliferation, differentiation, selection, death and migration of lymphocytes to peripheral tissues, where proliferation also occurs upon antigen recognition. Quantification of cell proliferation dynamics requires specific experimental methods and mathematical modelling. Here, we assess the impact of genetics and aging on the immune system by investigating the dynamics of proliferation of T lymphocytes across their differentiation through thymus and spleen in mice. Our investigation is based on single-cell multicolour flow cytometry analysis revealing the active incorporation of a thymidine analogue during S phase after pulse-chase-pulse experiments in vivo, versus cell DNA content. A generic mathematical model of state transition simulates through Ordinary Differential Equations (ODEs) the evolution of single cell behaviour during various durations of labelling. It allows us to fit our data, to deduce proliferation rates and estimate cell cycle durations in sub-populations. Our model is simple and flexible and is validated with other durations of pulse/chase experiments. Our results reveal that T cell proliferation is highly heterogeneous but with a specific "signature" that depends upon genetic origins, is specific to cell differentiation stages in thymus and spleen and is altered with age. In conclusion, our model allows us to infer proliferation rates and cell cycle phase durations from complex experimental 5-ethynyl-2'-deoxyuridine (EdU) data, revealing T cell proliferation heterogeneity and specific signatures.

  15. Reassessing the NTCTCS Staging Systems for Differentiated Thyroid Cancer, Including Age at Diagnosis

    PubMed Central

    McLeod, Donald S.A.; Jonklaas, Jacqueline; Brierley, James D.; Ain, Kenneth B.; Cooper, David S.; Fein, Henry G.; Haugen, Bryan R.; Ladenson, Paul W.; Magner, James; Ross, Douglas S.; Skarulis, Monica C.; Steward, David L.; Xing, Mingzhao; Litofsky, Danielle R.; Maxon, Harry R.

    2015-01-01

    Background: Thyroid cancer is unique for having age as a staging variable. Recently, the commonly used age cut-point of 45 years has been questioned. Objective: This study assessed alternate staging systems on the outcome of overall survival, and compared these with current National Thyroid Cancer Treatment Cooperative Study (NTCTCS) staging systems for papillary and follicular thyroid cancer. Methods: A total of 4721 patients with differentiated thyroid cancer were assessed. Five potential alternate staging systems were generated at age cut-points in five-year increments from 35 to 70 years, and tested for model discrimination (Harrell's C-statistic) and calibration (R2). The best five models for papillary and follicular cancer were further tested with bootstrap resampling and significance testing for discrimination. Results: The best five alternate papillary cancer systems had age cut-points of 45–50 years, with the highest scoring model using 50 years. No significant difference in C-statistic was found between the best alternate and current NTCTCS systems (p = 0.200). The best five alternate follicular cancer systems had age cut-points of 50–55 years, with the highest scoring model using 50 years. All five best alternate staging systems performed better compared with the current system (p = 0.003–0.035). There was no significant difference in discrimination between the best alternate system (cut-point age 50 years) and the best system of cut-point age 45 years (p = 0.197). Conclusions: No alternate papillary cancer systems assessed were significantly better than the current system. New alternate staging systems for follicular cancer appear to be better than the current NTCTCS system, although they require external validation. PMID:26203804

  16. Biomedical semantics in the Semantic Web.

    PubMed

    Splendiani, Andrea; Burger, Albert; Paschke, Adrian; Romano, Paolo; Marshall, M Scott

    2011-03-07

    The Semantic Web offers an ideal platform for representing and linking biomedical information, which is a prerequisite for the development and application of analytical tools to address problems in data-intensive areas such as systems biology and translational medicine. As for any new paradigm, the adoption of the Semantic Web offers opportunities and poses questions and challenges to the life sciences scientific community: which technologies in the Semantic Web stack will be more beneficial for the life sciences? Is biomedical information too complex to benefit from simple interlinked representations? What are the implications of adopting a new paradigm for knowledge representation? What are the incentives for the adoption of the Semantic Web, and who are the facilitators? Is there going to be a Semantic Web revolution in the life sciences?We report here a few reflections on these questions, following discussions at the SWAT4LS (Semantic Web Applications and Tools for Life Sciences) workshop series, of which this Journal of Biomedical Semantics special issue presents selected papers from the 2009 edition, held in Amsterdam on November 20th.

  17. Lexical Semantics and Irregular Inflection

    PubMed Central

    Huang, Yi Ting; Pinker, Steven

    2010-01-01

    Whether a word has an irregular inflection does not depend on its sound alone: compare lie-lay (recline) and lie-lied (prevaricate). Theories of morphology, particularly connectionist and symbolic models, disagree on which nonphonological factors are responsible. We test four possibilities: (1) Lexical effects, in which two lemmas differ in whether they specify an irregular form; (2) Semantic effects, in which the semantic features of a word become associated with regular or irregular forms; (3) Morphological structure effects, in which a word with a headless structure (e.g., a verb derived from a noun) blocks access to a stored irregular form; (4) Compositionality effects, in which the stored combination of an irregular word’s meaning (e.g., the verb’s inherent aspect) with the meaning of the inflection (e.g., pastness) doesn’t readily transfer to new senses with different combinations of such meanings. In four experiments, speakers were presented with existing and novel verbs and asked to rate their past-tense forms, semantic similarities, grammatical structure, and aspectual similarities. We found (1) an interaction between semantic and phonological similarity, coinciding with reported strategies of analogizing to known verbs and implicating lexical effects; (2) weak and inconsistent effects of semantic similarity; (3) robust effects of morphological structure, and (4) robust effects of aspectual compositionality. Results are consistent with theories of language that invoke lexical entries and morphological structure, and which differentiate the mode of storage of regular and irregular verbs. They also suggest how psycholinguistic processes have shaped vocabulary structure over history. PMID:21151703

  18. Abstract algebraic-delay differential systems and age structured population dynamics

    NASA Astrophysics Data System (ADS)

    Kosovalić, N.; Magpantay, F. M. G.; Chen, Y.; Wu, J.

    We consider the abstract algebraic-delay differential system, x'(t)=Ax(t)+F(x(t),a(t)), a(t)=H(xt,at). Here A is a linear operator on D(A)⊂X satisfying the Hille-Yosida conditions, x(t)∈D(A)¯⊂X, and a(t)∈Rn, where X is a real Banach space. With a global Lipschitz condition on F and an appropriate hypothesis on the function H, we show that the corresponding initial value problem gives rise to a continuous semiflow in a subset of the space of continuous functions. We establish the positivity of the x-component and give some examples arising from age structured population dynamics. The examples come from situations where the age of maturity of an individual at a given time is determined by whether or not the resource concentration density, which depends on the immature population, reaches a prescribed threshold within that time.

  19. Dietary restriction improves repopulation but impairs lymphoid differentiation capacity of hematopoietic stem cells in early aging

    PubMed Central

    Tang, Duozhuang; Tao, Si; Chen, Zhiyang; Koliesnik, Ievgen Oleksandrovich; Calmes, Philip Gerald; Hoerr, Verena; Han, Bing; Gebert, Nadja; Zörnig, Martin; Löffler, Bettina

    2016-01-01

    Dietary restriction (DR) improves health, delays tissue aging, and elongates survival in flies and worms. However, studies on laboratory mice and nonhuman primates revealed ambiguous effects of DR on lifespan despite improvements in health parameters. In this study, we analyzed consequences of adult-onset DR (24 h to 1 yr) on hematopoietic stem cell (HSC) function. DR ameliorated HSC aging phenotypes, such as the increase in number of HSCs and the skewing toward myeloid-biased HSCs during aging. Furthermore, DR increased HSC quiescence and improved the maintenance of the repopulation capacity of HSCs during aging. In contrast to these beneficial effects, DR strongly impaired HSC differentiation into lymphoid lineages and particularly inhibited the proliferation of lymphoid progenitors, resulting in decreased production of peripheral B lymphocytes and impaired immune function. The study shows that DR-dependent suppression of growth factors and interleukins mediates these divergent effects caused by DR. Supplementation of insulin-like growth factor 1 partially reverted the DR-induced quiescence of HSCs, whereas IL-6/IL-7 substitutions rescued the impairment of B lymphopoiesis exposed to DR. Together, these findings delineate positive and negative effects of long-term DR on HSC functionality involving distinct stress and growth signaling pathways. PMID:26951333

  20. Neocortex and allocortex respond differentially to cellular stress in vitro and aging in vivo.

    PubMed

    Posimo, Jessica M; Titler, Amanda M; Choi, Hailey J H; Unnithan, Ajay S; Leak, Rehana K

    2013-01-01

    In Parkinson's and Alzheimer's diseases, the allocortex accumulates aggregated proteins such as synuclein and tau well before neocortex. We present a new high-throughput model of this topographic difference by microdissecting neocortex and allocortex from the postnatal rat and treating them in parallel fashion with toxins. Allocortical cultures were more vulnerable to low concentrations of the proteasome inhibitors MG132 and PSI but not the oxidative poison H2O2. The proteasome appeared to be more impaired in allocortex because MG132 raised ubiquitin-conjugated proteins and lowered proteasome activity in allocortex more than neocortex. Allocortex cultures were more vulnerable to MG132 despite greater MG132-induced rises in heat shock protein 70, heme oxygenase 1, and catalase. Proteasome subunits PA700 and PA28 were also higher in allocortex cultures, suggesting compensatory adaptations to greater proteasome impairment. Glutathione and ceruloplasmin were not robustly MG132-responsive and were basally higher in neocortical cultures. Notably, neocortex cultures became as vulnerable to MG132 as allocortex when glutathione synthesis or autophagic defenses were inhibited. Conversely, the glutathione precursor N-acetyl cysteine rendered allocortex resilient to MG132. Glutathione and ceruloplasmin levels were then examined in vivo as a function of age because aging is a natural model of proteasome inhibition and oxidative stress. Allocortical glutathione levels rose linearly with age but were similar to neocortex in whole tissue lysates. In contrast, ceruloplasmin levels were strikingly higher in neocortex at all ages and rose linearly until middle age. PA28 levels rose with age and were higher in allocortex in vivo, also paralleling in vitro data. These neo- and allocortical differences have implications for the many studies that treat the telencephalic mantle as a single unit. Our observations suggest that the topographic progression of protein aggregations through the

  1. Gender differentials and old age survival in the Nairobi slums, Kenya.

    PubMed

    Bennett, Rachel; Chepngeno-Langat, Gloria; Evandrou, Maria; Falkingham, Jane

    2016-08-01

    This paper examines gender differentials in survival amongst older people (50+ years) in the Nairobi slums and to the best of our knowledge is the first study of its kind in an urban African setting. The results provide evidence contrary to the expected paradox of poorer self-rated health yet better survival amongst older women. Older women in the Nairobi slums have poorer self-rated health and poorer circumstances across other factors, including disability and socio-economic status. Further, older women in the slums do not have better survival. The conventional female advantage in mortality only becomes apparent after accounting for the cumulative influence of individual characteristics, social networks, health and socio-economic status, suggesting the female advantage in unadjusted old-age mortality does not apply to contexts where women experience significant disadvantage across multiple life domains. This highlights the urgent need to redress the support, status and opportunities available for women across the life course in contexts such as the Nairobi slums. In addition, a greater number of factors differentiate mortality risk amongst men than amongst women, suggesting inequality amongst slum dwelling older men and highlighting the need for gender sensitive interventions which account for the particular needs of both genders in old age.

  2. Novel hydrated graphene ribbon unexpectedly promotes aged seed germination and root differentiation

    PubMed Central

    Hu, Xiangang; Zhou, Qixing

    2014-01-01

    It is well known that graphene (G) induces nanotoxicity towards living organisms. Here, a novel and biocompatible hydrated graphene ribbon (HGR) unexpectedly promoted aged (two years) seed germination. HGR formed at the normal temperature and pressure (120 days hydration), presented 17.1% oxygen, 0.9% nitrogen groups, disorder-layer structure, with 0.38 nm thickness ribbon morphology. Interestingly, there were bulges around the edges of HGR. Compared to G and graphene oxide (GO), HGR increased seed germination by 15% root differentiation between 52 and 59% and enhanced resistance to oxidative stress. The metabonomics analysis discovered that HGR upregulated carbohydrate, amino acid, and fatty acids metabolism that determined secondary metabolism, nitrogen sequestration, cell membrane integrity, permeability, and oxidation resistance. Hexadecanoic acid as a biomarker promoted root differentiation and increased the germination rate. Our discovery is a novel HGR that promotes aged seed germination, illustrates metabolic specificity among graphene-based materials, and inspires innovative concepts in the regulation of seed development. PMID:24445438

  3. Novel hydrated graphene ribbon unexpectedly promotes aged seed germination and root differentiation

    NASA Astrophysics Data System (ADS)

    Hu, Xiangang; Zhou, Qixing

    2014-01-01

    It is well known that graphene (G) induces nanotoxicity towards living organisms. Here, a novel and biocompatible hydrated graphene ribbon (HGR) unexpectedly promoted aged (two years) seed germination. HGR formed at the normal temperature and pressure (120 days hydration), presented 17.1% oxygen, 0.9% nitrogen groups, disorder-layer structure, with 0.38 nm thickness ribbon morphology. Interestingly, there were bulges around the edges of HGR. Compared to G and graphene oxide (GO), HGR increased seed germination by 15% root differentiation between 52 and 59% and enhanced resistance to oxidative stress. The metabonomics analysis discovered that HGR upregulated carbohydrate, amino acid, and fatty acids metabolism that determined secondary metabolism, nitrogen sequestration, cell membrane integrity, permeability, and oxidation resistance. Hexadecanoic acid as a biomarker promoted root differentiation and increased the germination rate. Our discovery is a novel HGR that promotes aged seed germination, illustrates metabolic specificity among graphene-based materials, and inspires innovative concepts in the regulation of seed development.

  4. Replication-dependent histone genes are actively transcribed in differentiating and aging retinal neurons.

    PubMed

    Banday, Abdul Rouf; Baumgartner, Marybeth; Al Seesi, Sahar; Karunakaran, Devi Krishna Priya; Venkatesh, Aditya; Congdon, Sean; Lemoine, Christopher; Kilcollins, Ashley M; Mandoiu, Ion; Punzo, Claudio; Kanadia, Rahul N

    2014-01-01

    In the mammalian genome, each histone family contains multiple replication-dependent paralogs, which are found in clusters where their transcription is thought to be coupled to the cell cycle. Here, we wanted to interrogate the transcriptional regulation of these paralogs during retinal development and aging. We employed deep sequencing, quantitative PCR, in situ hybridization (ISH), and microarray analysis, which revealed that replication-dependent histone genes were not only transcribed in progenitor cells but also in differentiating neurons. Specifically, by ISH analysis we found that different histone genes were actively transcribed in a subset of neurons between postnatal day 7 and 14. Interestingly, within a histone family, not all paralogs were transcribed at the same level during retinal development. For example, expression of Hist1h1b was higher embryonically, while that of Hist1h1c was higher postnatally. Finally, expression of replication-dependent histone genes was also observed in the aging retina. Moreover, transcription of replication-dependent histones was independent of rapamycin-mediated mTOR pathway inactivation. Overall, our data suggest the existence of variant nucleosomes produced by the differential expression of the replication-dependent histone genes across retinal development. Also, the expression of a subset of replication-dependent histone isotypes in senescent neurons warrants re-examining these genes as "replication-dependent." Thus, our findings underscore the importance of understanding the transcriptional regulation of replication-dependent histone genes in the maintenance and functioning of neurons.

  5. Age-related alterations in mesenchymal stem cells related to shift in differentiation from osteogenic to adipogenic potential: implication to age-associated bone diseases and defects.

    PubMed

    Kim, MiJung; Kim, ChanWha; Choi, Yu Suk; Kim, MinHwan; Park, ChanJeoung; Suh, Yousin

    2012-05-01

    Mesenchymal stem cells (MSC) have attracted considerable attention in the fields of cell and gene therapy due to their intrinsic ability to differentiate into multiple lineages. The various therapeutic applications involving MSC require initial expansion and/or differentiation in vitro prior to clinical use. However, serial passages of MSC in culture lead to decreased differentiation potential and stem cell characteristics, eventually inducing cellular aging which will limit the success of cell-based therapeutic interventions. Here we review the age-related changes that occur in MSC with a special focus on the shift of differentiation potential from osteogenic to adipogenic lineage during the MSC aging processes and how aging causes this preferential shift by oxidative stress and/or energy metabolism defect. Oxidative stress-related signals and some microRNAs affect the differentiation potential shift of MSC by directly targeting key regulatory factors such as Runx-2 or PPAR-γ, and energy metabolism pathway is involved as well. All information described here including transcription factors, microRNAs and FoxOs could be used towards development of treatment regimens for age-related bone diseases and related defects based on mutually exclusive lineage fate determination of MSC.

  6. Semantic Networks and Social Networks

    ERIC Educational Resources Information Center

    Downes, Stephen

    2005-01-01

    Purpose: To illustrate the need for social network metadata within semantic metadata. Design/methodology/approach: Surveys properties of social networks and the semantic web, suggests that social network analysis applies to semantic content, argues that semantic content is more searchable if social network metadata is merged with semantic web…

  7. Neuroeconomic dissociation of semantic dementia and behavioural variant frontotemporal dementia

    PubMed Central

    Wood, Kristie A.; Beagle, Alexander J.; Hsu, Ming; Kayser, Andrew S.; Miller, Bruce L.; Kramer, Joel H.

    2016-01-01

    Many neuropsychiatric disorders are marked by abnormal behaviour and decision-making, but prevailing diagnostic criteria for such behaviours are typically qualitative and often ambiguous. Behavioural variant frontotemporal dementia and semantic variant primary progressive aphasia (also called semantic dementia) are two clinical variants of frontotemporal dementia with overlapping but distinct anatomical substrates known to cause profound changes in decision-making. We investigated whether abnormal decision-making in these syndromes could be more precisely characterized in terms of dissociable abnormalities in patients’ subjective evaluations of valence (positive versus negative outcome) and of time (present versus future outcome). We presented 28 patients with behavioural variant frontotemporal dementia, 14 patients with semantic variant primary progressive aphasia, 25 patients with Alzheimer’s disease (as disease controls), and 61 healthy older control subjects with experimental tasks assaying loss aversion and delay discounting. In general linear models controlling for age, gender, education and Mini-Mental State Examination score, patients with behavioural variant frontotemporal dementia were less averse to losses than control subjects (P < 0.001), while patients with semantic variant primary progressive aphasia discounted delayed rewards more steeply than controls (P = 0.019). There was no relationship between loss aversion and delay discounting across the sample, nor in any of the subgroups. These findings suggest that abnormal behaviours in neurodegenerative disease may result from the disruption of either of two dissociable neural processes for evaluating the outcomes of action. More broadly, these findings suggest a role for computational methods to supplement traditional qualitative characterizations in the differential diagnosis of neuropsychiatric disorders. PMID:26667277

  8. Response to cartoons and attitudes toward aging.

    PubMed

    Sheppard, A

    1981-01-01

    Although it has commonly been asserted that cartoon images of aging convey deep psychological significance, the relationship between attitudes and cartoon appreciation has received little systematic attention. The present study examined the relationship between responses to cartoons and attitudes toward aging among college students. Subjects rated the funniness of 60 cartoons and completed the Attitudes Toward Aging Inventory, Tuckman-Lorge, and Semantic Differential. Factor analysis revealed four categories of cartoons on aging: Disparagement, Ineffectuality, Obsolescence, and Isolation. No significant relationships were found between attitudes and humor appreciation, although age and education were inversely related to several cartoon themes.

  9. Lunar basalt chronology, mantle differentiation and implications for determining the age of the Moon

    NASA Astrophysics Data System (ADS)

    Snape, Joshua F.; Nemchin, Alexander A.; Bellucci, Jeremy J.; Whitehouse, Martin J.; Tartèse, Romain; Barnes, Jessica J.; Anand, Mahesh; Crawford, Ian A.; Joy, Katherine H.

    2016-10-01

    Despite more than 40 years of studying Apollo samples, the age and early evolution of the Moon remain contentious. Following the formation of the Moon in the aftermath of a giant impact, the resulting Lunar Magma Ocean (LMO) is predicted to have generated major geochemically distinct silicate reservoirs, including the sources of lunar basalts. Samples of these basalts, therefore, provide a unique opportunity to characterize these reservoirs. However, the precise timing and extent of geochemical fractionation is poorly constrained, not least due to the difficulty in determining accurate ages and initial Pb isotopic compositions of lunar basalts. Application of an in situ ion microprobe approach to Pb isotope analysis has allowed us to obtain precise crystallization ages from six lunar basalts, typically with an uncertainty of about ± 10 Ma, as well as constrain their initial Pb-isotopic compositions. This has enabled construction of a two-stage model for the Pb-isotopic evolution of lunar silicate reservoirs, which necessitates the prolonged existence of high-μ reservoirs in order to explain the very radiogenic compositions of the samples. Further, once firm constraints on U and Pb partitioning behaviour are established, this model has the potential to help distinguish between conflicting estimates for the age of the Moon. Nonetheless, we are able to constrain the timing of a lunar mantle reservoir differentiation event at 4376 ± 18 Ma, which is consistent with that derived from the Sm-Nd and Lu-Hf isotopic systems, and is interpreted as an average estimate of the time at which the high-μ urKREEP reservoir was established and the Ferroan Anorthosite (FAN) suite was formed.

  10. Differential DNA Methylation in Relation to Age and Health Risks of Obesity.

    PubMed

    Mansego, María Luisa; Milagro, Fermín I; Zulet, María Ángeles; Moreno-Aliaga, María J; Martínez, José Alfredo

    2015-07-24

    The aim of this study was to evaluate whether genome-wide levels of DNA methylation are associated with age and the health risks of obesity (HRO); defined according to BMI categories as "Low HRO" (overweight and class 1 obesity) versus "High HRO" (class 2 and class 3 obesity). Anthropometric measurements were assessed in a subsample of 48 volunteers from the Metabolic Syndrome Reduction in Navarra (RESMENA) study and 24 women from another independent study, Effects of Lipoic Acid and Eicosapentaenoic Acid in Human Obesity (OBEPALIP study). In the pooled population; the methylation levels of 55 CpG sites were significantly associated with age after Benjamini-Hochberg correction. In addition, DNA methylation of three CpG sites located in ELOVL2; HOXC4 and PI4KB were further negatively associated with their mRNA levels. Although no differentially methylated CpG sites were identified in relation to HRO after multiple testing correction; several nominally significant CpG sites were identified in genes related to insulin signaling; energy and lipid metabolism. Moreover, statistically significant associations between BMI or mRNA levels and two HRO-related CpG sites located in GPR133 and ITGB5 are reported. As a conclusion, these findings from two Spanish cohorts add knowledge about the important role of DNA methylation in the age-related regulation of gene expression. In addition; a relevant influence of age on DNA methylation in white blood cells was found, as well as, on a trend level, novel associations between DNA methylation and obesity.

  11. Differential DNA Methylation in Relation to Age and Health Risks of Obesity

    PubMed Central

    Mansego, María Luisa; Milagro, Fermín I.; Zulet, María Ángeles; Moreno-Aliaga, María J.; Martínez, José Alfredo

    2015-01-01

    The aim of this study was to evaluate whether genome-wide levels of DNA methylation are associated with age and the health risks of obesity (HRO); defined according to BMI categories as “Low HRO” (overweight and class 1 obesity) versus “High HRO” (class 2 and class 3 obesity). Anthropometric measurements were assessed in a subsample of 48 volunteers from the Metabolic Syndrome Reduction in Navarra (RESMENA) study and 24 women from another independent study, Effects of Lipoic Acid and Eicosapentaenoic Acid in Human Obesity (OBEPALIP study). In the pooled population; the methylation levels of 55 CpG sites were significantly associated with age after Benjamini-Hochberg correction. In addition, DNA methylation of three CpG sites located in ELOVL2; HOXC4 and PI4KB were further negatively associated with their mRNA levels. Although no differentially methylated CpG sites were identified in relation to HRO after multiple testing correction; several nominally significant CpG sites were identified in genes related to insulin signaling; energy and lipid metabolism. Moreover, statistically significant associations between BMI or mRNA levels and two HRO-related CpG sites located in GPR133 and ITGB5 are reported. As a conclusion, these findings from two Spanish cohorts add knowledge about the important role of DNA methylation in the age-related regulation of gene expression. In addition; a relevant influence of age on DNA methylation in white blood cells was found, as well as, on a trend level, novel associations between DNA methylation and obesity. PMID:26213922

  12. Nativity Differentials in Older Age Mortality in Taiwan: Do They Exist and Why?

    PubMed Central

    Hermalin, Albert I.; Ofstedal, Mary Beth; Sun, Cathy; Liu, I-Wen

    2011-01-01

    Comparisons of migrants versus native populations have become increasingly important as a means of gaining insight into the factors affecting health and mortality levels and the relationship between them. Taiwan underwent a unique migration in 1949–50, as more than a million people, mostly young men, arrived from Mainland China following the Communist civil war victory. The Mainlanders were distinct from the original settlers in several ways: they represented different provinces in China, were better educated, and had distinct occupational profiles. Since 1950, Taiwan has experienced a rapid demographic transition and notable economic development, resulting in mortality decline. In this paper, we generate age- and cause-specific death rates circa 1990 by education and nativity to evaluate the relative importance of each factor. We also use longitudinal survey data to help interpret the differentials in terms of selection, risk factors, and other dynamics of health and mortality. PMID:21887404

  13. Differentiating Aging Among Adults With Down Syndrome and Comorbid Dementia or Psychopathology.

    PubMed

    Esbensen, Anna J; Johnson, Emily Boshkoff; Amaral, Joseph L; Tan, Christine M; Macks, Ryan

    2016-01-01

    Differences were examined between three groups of adults with Down syndrome in their behavioral presentation, social life/activities, health, and support needs. We compared those with comorbid dementia, with comorbid psychopathology, and with no comorbid conditions. Adults with comorbid dementia were more likely to be older, have lower functional abilities, have worse health and more health conditions, and need more support in self-care. Adults with comorbid psychopathology were more likely to exhibit more behavior problems and to be living at home with their families. Adults with no comorbidities were most likely to be involved in community employment. Differences in behavioral presentation can help facilitate clinical diagnoses in aging in Down syndrome, and implications for differential diagnosis and service supports are discussed.

  14. Differential expression of sirtuin family members in the developing, adult, and aged rat brain.

    PubMed

    Sidorova-Darmos, Elena; Wither, Robert G; Shulyakova, Natalya; Fisher, Carl; Ratnam, Melanie; Aarts, Michelle; Lilge, Lothar; Monnier, Philippe P; Eubanks, James H

    2014-01-01

    The sirtuins are NAD(+)-dependent protein deacetylases and/or ADP-ribosyltransferases that play roles in metabolic homeostasis, stress response and potentially aging. This enzyme family resides in different subcellular compartments, and acts on a number of different targets in the nucleus, cytoplasm and in the mitochondria. Despite their recognized ability to regulate metabolic processes, the roles played by specific sirtuins in the brain-the most energy demanding tissue in the body-remains less well investigated and understood. In the present study, we examined the regional mRNA and protein expression patterns of individual sirtuin family members in the developing, adult, and aged rat brain. Our results show that while each sirtuin is expressed in the brain at each of these different stages, they display unique spatial and temporal expression patterns within the brain. Further, for specific members of the family, the protein expression profile did not coincide with their respective mRNA expression profile. Moreover, using primary cultures enriched for neurons and astrocytes respectively, we found that specific sirtuin members display preferential neural lineage expression. Collectively, these results provide the first composite illustration that sirtuin family members display differential expression patterns in the brain, and provide evidence that specific sirtuins could potentially be targeted to achieve cell-type selective effects within the brain.

  15. Differential expression of sirtuin family members in the developing, adult, and aged rat brain

    PubMed Central

    Sidorova-Darmos, Elena; Wither, Robert G.; Shulyakova, Natalya; Fisher, Carl; Ratnam, Melanie; Aarts, Michelle; Lilge, Lothar; Monnier, Philippe P.; Eubanks, James H.

    2014-01-01

    The sirtuins are NAD+-dependent protein deacetylases and/or ADP-ribosyltransferases that play roles in metabolic homeostasis, stress response and potentially aging. This enzyme family resides in different subcellular compartments, and acts on a number of different targets in the nucleus, cytoplasm and in the mitochondria. Despite their recognized ability to regulate metabolic processes, the roles played by specific sirtuins in the brain—the most energy demanding tissue in the body—remains less well investigated and understood. In the present study, we examined the regional mRNA and protein expression patterns of individual sirtuin family members in the developing, adult, and aged rat brain. Our results show that while each sirtuin is expressed in the brain at each of these different stages, they display unique spatial and temporal expression patterns within the brain. Further, for specific members of the family, the protein expression profile did not coincide with their respective mRNA expression profile. Moreover, using primary cultures enriched for neurons and astrocytes respectively, we found that specific sirtuin members display preferential neural lineage expression. Collectively, these results provide the first composite illustration that sirtuin family members display differential expression patterns in the brain, and provide evidence that specific sirtuins could potentially be targeted to achieve cell-type selective effects within the brain. PMID:25566066

  16. Prenatal ethanol exposure differentially affects hippocampal neurogenesis in the adolescent and aged brain.

    PubMed

    Gil-Mohapel, J; Titterness, A K; Patten, A R; Taylor, S; Ratzlaff, A; Ratzlaff, T; Helfer, J; Christie, B R

    2014-07-25

    Exposure to ethanol in utero is associated with a myriad of sequelae for the offspring. Some of these effects are morphological in nature and noticeable from birth, while others involve more subtle changes to the brain that only become apparent later in life when the individuals are challenged cognitively. One brain structure that shows both functional and structural deficits following prenatal ethanol exposure is the hippocampus. The hippocampus is composed of two interlocking gyri, the cornu ammonis (CA) and the dentate gyrus (DG), and they are differentially affected by prenatal ethanol exposure. The CA shows a more consistent loss in neuronal numbers, with different ethanol exposure paradigms, than the DG, which in contrast shows more pronounced and consistent deficits in synaptic plasticity. In this study we show that significant deficits in adult hippocampal neurogenesis are apparent in aged animals following prenatal ethanol exposure. Deficits in hippocampal neurogenesis were not apparent in younger animals. Surprisingly, even when ethanol exposure occurred in conjunction with maternal stress, deficits in neurogenesis did not occur at this young age, suggesting that the capacity for neurogenesis is highly conserved early in life. These findings are unique in that they demonstrate for the first time that deficits in neurogenesis associated with prenatal ethanol consumption appear later in life.

  17. Field study of age-differentiated strain for assembly line workers in the automotive industry.

    PubMed

    Börner, Kerstin; Scherf, Christian; Leitner-Mai, Bianca; Spanner-Ulmer, Birgit

    2012-01-01

    A field study in an automotive supply industry company was conducted to explore age-differentiated strain of assembly line workers. Subjective and objective data from 23 female workers aged between 27 and 57 years were collected at the workplace belt buckle assembly during morning shifts. Subjects with medication or chronic diseases affecting heart rate and breath rate were excluded. For subjective data generation different questionnaires were used. Before the Work Ability Index and the Munich Chronotype Questionnaire were completed by the subjects. Short questionnaires (strain-ratings, NASA-TLX) directly at begin and end of the work were used for obtaining shift-related data. During the whole shift (6 a.m. - 2.45 p.m.) bodily functions were logged with a wireless chest strap. In addition, the motion of the hand-arm-system was recorded for 30 times, 3 minutes each after a fixed time-schedule. First results show that younger subjects need significant less time for assembly (mean = 14.940 s) compared to older subjects (mean = 17.040 s; t(472.026) = -9.278 , p < 0.01).

  18. Activation of Phonological and Semantic Codes in Toddlers

    ERIC Educational Resources Information Center

    Mani, Nivedita; Durrant, Samantha; Floccia, Caroline

    2012-01-01

    What are the processes underlying word recognition in the toddler lexicon? Work with adults suggests that, by 5-years of age, hearing a word leads to cascaded activation of other phonologically, semantically and phono-semantically related words (Huang & Snedeker, 2010; Marslen-Wilson & Zwitserlood, 1989). Given substantial differences in…

  19. The Semantic Learning Organization

    ERIC Educational Resources Information Center

    Sicilia, Miguel-Angel; Lytras, Miltiadis D.

    2005-01-01

    Purpose: The aim of this paper is introducing the concept of a "semantic learning organization" (SLO) as an extension of the concept of "learning organization" in the technological domain. Design/methodology/approach: The paper takes existing definitions and conceptualizations of both learning organizations and Semantic Web technology to develop…

  20. H3K4me1 marks DNA regions hypomethylated during aging in human stem and differentiated cells

    PubMed Central

    Fernández, Agustín F.; Bayón, Gustavo F.; Urdinguio, Rocío G.; Toraño, Estela G.; García, María G.; Carella, Antonella; Petrus-Reurer, Sandra; Ferrero, Cecilia; Martinez-Camblor, Pablo; Cubillo, Isabel; García-Castro, Javier; Delgado-Calle, Jesús; Pérez-Campo, Flor M.; Riancho, José A.; Bueno, Clara; Menéndez, Pablo; Mentink, Anouk; Mareschi, Katia; Claire, Fabian; Fagnani, Corrado; Medda, Emanuela; Toccaceli, Virgilia; Brescianini, Sonia; Moran, Sebastián; Esteller, Manel; Stolzing, Alexandra; de Boer, Jan; Nisticò, Lorenza; Stazi, Maria A.

    2015-01-01

    In differentiated cells, aging is associated with hypermethylation of DNA regions enriched in repressive histone post-translational modifications. However, the chromatin marks associated with changes in DNA methylation in adult stem cells during lifetime are still largely unknown. Here, DNA methylation profiling of mesenchymal stem cells (MSCs) obtained from individuals aged 2 to 92 yr identified 18,735 hypermethylated and 45,407 hypomethylated CpG sites associated with aging. As in differentiated cells, hypermethylated sequences were enriched in chromatin repressive marks. Most importantly, hypomethylated CpG sites were strongly enriched in the active chromatin mark H3K4me1 in stem and differentiated cells, suggesting this is a cell type–independent chromatin signature of DNA hypomethylation during aging. Analysis of scedasticity showed that interindividual variability of DNA methylation increased during aging in MSCs and differentiated cells, providing a new avenue for the identification of DNA methylation changes over time. DNA methylation profiling of genetically identical individuals showed that both the tendency of DNA methylation changes and scedasticity depended on nongenetic as well as genetic factors. Our results indicate that the dynamics of DNA methylation during aging depend on a complex mixture of factors that include the DNA sequence, cell type, and chromatin context involved and that, depending on the locus, the changes can be modulated by genetic and/or external factors. PMID:25271306

  1. H3K4me1 marks DNA regions hypomethylated during aging in human stem and differentiated cells.

    PubMed

    Fernández, Agustín F; Bayón, Gustavo F; Urdinguio, Rocío G; Toraño, Estela G; García, María G; Carella, Antonella; Petrus-Reurer, Sandra; Ferrero, Cecilia; Martinez-Camblor, Pablo; Cubillo, Isabel; García-Castro, Javier; Delgado-Calle, Jesús; Pérez-Campo, Flor M; Riancho, José A; Bueno, Clara; Menéndez, Pablo; Mentink, Anouk; Mareschi, Katia; Claire, Fabian; Fagnani, Corrado; Medda, Emanuela; Toccaceli, Virgilia; Brescianini, Sonia; Moran, Sebastián; Esteller, Manel; Stolzing, Alexandra; de Boer, Jan; Nisticò, Lorenza; Stazi, Maria A; Fraga, Mario F

    2015-01-01

    In differentiated cells, aging is associated with hypermethylation of DNA regions enriched in repressive histone post-translational modifications. However, the chromatin marks associated with changes in DNA methylation in adult stem cells during lifetime are still largely unknown. Here, DNA methylation profiling of mesenchymal stem cells (MSCs) obtained from individuals aged 2 to 92 yr identified 18,735 hypermethylated and 45,407 hypomethylated CpG sites associated with aging. As in differentiated cells, hypermethylated sequences were enriched in chromatin repressive marks. Most importantly, hypomethylated CpG sites were strongly enriched in the active chromatin mark H3K4me1 in stem and differentiated cells, suggesting this is a cell type-independent chromatin signature of DNA hypomethylation during aging. Analysis of scedasticity showed that interindividual variability of DNA methylation increased during aging in MSCs and differentiated cells, providing a new avenue for the identification of DNA methylation changes over time. DNA methylation profiling of genetically identical individuals showed that both the tendency of DNA methylation changes and scedasticity depended on nongenetic as well as genetic factors. Our results indicate that the dynamics of DNA methylation during aging depend on a complex mixture of factors that include the DNA sequence, cell type, and chromatin context involved and that, depending on the locus, the changes can be modulated by genetic and/or external factors.

  2. Semantic Sensor Web

    NASA Astrophysics Data System (ADS)

    Sheth, A.; Henson, C.; Thirunarayan, K.

    2008-12-01

    Sensors are distributed across the globe leading to an avalanche of data about our environment. It is possible today to utilize networks of sensors to detect and identify a multitude of observations, from simple phenomena to complex events and situations. The lack of integration and communication between these networks, however, often isolates important data streams and intensifies the existing problem of too much data and not enough knowledge. With a view to addressing this problem, the Semantic Sensor Web (SSW) [1] proposes that sensor data be annotated with semantic metadata that will both increase interoperability and provide contextual information essential for situational knowledge. Kno.e.sis Center's approach to SSW is an evolutionary one. It adds semantic annotations to the existing standard sensor languages of the Sensor Web Enablement (SWE) defined by OGC. These annotations enhance primarily syntactic XML-based descriptions in OGC's SWE languages with microformats, and W3C's Semantic Web languages- RDF and OWL. In association with semantic annotation and semantic web capabilities including ontologies and rules, SSW supports interoperability, analysis and reasoning over heterogeneous multi-modal sensor data. In this presentation, we will also demonstrate a mashup with support for complex spatio-temporal-thematic queries [2] and semantic analysis that utilize semantic annotations, multiple ontologies and rules. It uses existing services (e.g., GoogleMap) and semantics enhanced SWE's Sensor Observation Service (SOS) over weather and road condition data from various sensors that are part of Ohio's transportation network. Our upcoming plans are to demonstrate end to end (heterogeneous sensor to application) semantics support and study scalability of SSW involving thousands of sensors to about a billion triples. Keywords: Semantic Sensor Web, Spatiotemporal thematic queries, Semantic Web Enablement, Sensor Observation Service [1] Amit Sheth, Cory Henson, Satya

  3. Diet, age, and prior injury status differentially alter behavioral outcomes following concussion in rats.

    PubMed

    Mychasiuk, Richelle; Hehar, Harleen; van Waes, Linda; Esser, Michael J

    2015-01-01

    Mild traumatic brain injury (mTBI) or concussion affects a large portion of the population and although many of these individuals recover completely, a small subset of people experience lingering symptomology and poor outcomes. Little is known about the factors that affect individual susceptibility or resilience to poor outcomes after mTBI and there are currently no biomarkers to delineate mTBI diagnosis or prognosis. Based upon the growing literature associated with caloric intake and altered neurological aging and the ambiguous link between repetitive mTBI and progressive neurodegeneration, the current study was designed to examine the effect of a high fat diet (HFD), developmental age, and repetitive mTBI on behavioral outcomes following a mTBI. In addition, telomere length was examined before and after experimental mTBI. Sprague Dawley rats were maintained on a HFD or standard rat chow throughout life (including the prenatal period) and then experienced an mTBI/concussion at P30, P30 and P60, or only at P60. Behavioral outcomes were examined using a test battery that was administered between P61-P80 and included; beam-walking, open field, elevated plus maze, novel context mismatch, Morris water task, and forced swim task. Animals with a P30 mTBI often demonstrated lingering symptomology that was still present during testing at P80. Injuries at P30 and P60 rarely produced cumulative effects, and in some tests (i.e., beam walking), the first injury may have protected the brain from the second injury. Exposure to the high fat diet exacerbated many of the behavioral deficits associated with concussion. Finally, telomere length was shortened following mTBI and was influenced by the animal's dietary intake. Diet, age at the time of injury, and the number of prior concussion incidents differentially contribute to behavioral deficits and may help explain individual variations in susceptibility and resilience to poor outcomes following an mTBI.

  4. Order Theoretical Semantic Recommendation

    SciTech Connect

    Joslyn, Cliff A.; Hogan, Emilie A.; Paulson, Patrick R.; Peterson, Elena S.; Stephan, Eric G.; Thomas, Dennis G.

    2013-07-23

    Mathematical concepts of order and ordering relations play multiple roles in semantic technologies. Discrete totally ordered data characterize both input streams and top-k rank-ordered recommendations and query output, while temporal attributes establish numerical total orders, either over time points or in the more complex case of startend temporal intervals. But also of note are the fully partially ordered data, including both lattices and non-lattices, which actually dominate the semantic strcuture of ontological systems. Scalar semantic similarities over partially-ordered semantic data are traditionally used to return rank-ordered recommendations, but these require complementation with true metrics available over partially ordered sets. In this paper we report on our work in the foundations of partial order measurement in ontologies, with application to top-k semantic recommendation in workflows.

  5. Enhancing medical database semantics.

    PubMed Central

    Leão, B. de F.; Pavan, A.

    1995-01-01

    Medical Databases deal with dynamic, heterogeneous and fuzzy data. The modeling of such complex domain demands powerful semantic data modeling methodologies. This paper describes GSM-Explorer a Case Tool that allows for the creation of relational databases using semantic data modeling techniques. GSM Explorer fully incorporates the Generic Semantic Data Model-GSM enabling knowledge engineers to model the application domain with the abstraction mechanisms of generalization/specialization, association and aggregation. The tool generates a structure that implements persistent database-objects through the automatic generation of customized SQL ANSI scripts that sustain the semantics defined in the higher lever. This paper emphasizes the system architecture and the mapping of the semantic model into relational tables. The present status of the project and its further developments are discussed in the Conclusions. PMID:8563288

  6. [Semantic dementia--a multimodal disorder of conceptual knowledge].

    PubMed

    Nishio, Yoshiyuki; Mori, Etsuro

    2009-11-01

    Semantic dementia (SD) is a clinical syndrome characterized by progressive loss of semantic memory/ conceptual knowledge and by bilateral, but usually asymmetric, atrophy of the anterior temporal lobes (ATLS). On the basis of the neuropsychological findings of SD, the two theoretical implications for the organization of semantic memory have been suggested. First, selective impairment of semantic memory in the early stages of SD contrasts with the isolated loss of episodic memory in patients with damage to the medial temporal lobes and other Papez's circuit components. This double dissociation provides empirical evidence for fractionation of explicit memory into the two subsystems with different neural underpinnings. Second, the multimodal nature of semantic deficits in SD leads to a seminal view that semantic memory is organized as an amodal system. The ATLs play a pivotal role as a 'convergence zone' or 'semantic hub' integrating abundant verbal and perceptual attributes that are represented in the posterior temporal and temporo-occipital cortices. To develop further comprehensive theories regarding semantic memory, we should understand differential roles of the left and right ATLs and clarify the clinicoanatomical relationship between verbal, visual, and emotional aspects of semantic memory loss and the detailed anatomical localization of the lesions.

  7. Adult and Child Semantic Neighbors of the Kroll and Potter (1984) Nonobjects

    ERIC Educational Resources Information Center

    Storkel, Holly L.; Adlof, Suzanne M.

    2009-01-01

    Purpose: The purpose was to determine the number of semantic neighbors, namely, "semantic set size," for 88 nonobjects (J. F. Kroll & M. C. Potter, 1984) and determine how semantic set size related to other measures and age. Method: Data were collected from 82 adults and 92 preschool children in a discrete association task. The nonobjects were…

  8. Semantics, Pragmatics, and the Nature of Semantic Theories

    ERIC Educational Resources Information Center

    Spewak, David Charles, Jr.

    2013-01-01

    The primary concern of this dissertation is determining the distinction between semantics and pragmatics and how context sensitivity should be accommodated within a semantic theory. I approach the question over how to distinguish semantics from pragmatics from a new angle by investigating what the objects of a semantic theory are, namely…

  9. Invariant and partially invariant solutions of integro-differential equations for linear thermoviscoelastic aging materials with memory

    NASA Astrophysics Data System (ADS)

    Zhou, Long-Qiao; Meleshko, Sergey V.

    2017-01-01

    A linear thermoviscoelastic model for homogeneous, aging materials with memory is established. A system of integro-differential equations is obtained by using two motions (a one-dimensional motion and a shearing motion) for this model. Applying the group analysis method to the system of integro-differential equations, the admitted Lie group is determined. Using this admitted Lie group, invariant and partially invariant solutions are found. The present paper gives a first example of application of partially invariant solutions to integro-differential equations.

  10. Differential Aging of Cerebral White Matter in Middle-Aged and Older Adults: A Seven-Year Follow-up

    PubMed Central

    Bender, Andrew R.; Völkle, Manuel C.; Raz, Naftali

    2015-01-01

    The few extant reports of longitudinal white matter (WM) changes in healthy aging, using diffusion tensor imaging (DTI), reveal substantial differences in change across brain regions and DTI indices. According to the last-in-first-out hypothesis of brain aging late-developing WM tracts may be particularly vulnerable to advanced age. To test this hypothesis we compared age-related changes in association, commissural and projection WM fiber regions using a skeletonized, region of interest DTI approach. Using linear mixed effects models, we evaluated the influences of age and vascular risk at baseline on seven-year changes in three indices of WM integrity and organization (axial diffusivity, AD, radial diffusivity, RD, and fractional anisotropy, FA) in healthy middle-aged and older adults (mean age = 65.4, SD = 9.0 years). Association fibers showed the most pronounced declines over time. Advanced age was associated with greater longitudinal changes in RD and FA, independent of fiber type. Furthermore, older age was associated with longitudinal RD increases in late-developing, but not early-developing projection fibers. These findings demonstrate the increased vulnerability of later developing WM regions and support the last-in-first-out hypothesis of brain aging. PMID:26481675

  11. Age-related BMAL1 change affects mouse bone marrow stromal cell proliferation and osteo-differentiation potential

    PubMed Central

    Chen, Yijia; Xu, Xiaomei; Tan, Zhen; Ye, Cui; Chen, Yangxi

    2012-01-01

    Introduction Aging people's bone regeneration potential is always impaired. Bone marrow stromal cells (MSCs) contain progenitors of osteoblasts. Donor age may affect MSCs’ proliferation and differentiation potential, but the genomic base is still unknown. Due to recent research's indication that a core circadian component, brain and muscle ARNT-like 1 protein (BMAL1), has a role in premature aging, we investigated the normal aging mechanism in mice with their MSCs and Bmal1 gene/protein level. Material and methods 1, 6 and 16 month old C57BL/6 mice were used and the bone marrow stromal cells were gained and cultured at early passage. Bmal1 gene and protein level were detected in these cells. Marrow stromal cells were also induced to differentiate to osteoblasts or adipocytes. Three groups of mice MSCs were compared on proliferation by flow cytometry, on cell senescence by SA-β-gal expression and after osteo-induction on osteogenic potential by the expression of osterix (Osx), alkaline phosphatase (ALP) and osteocalcin (OCN). Results Bmal1 gene and protein level as well as S-phase fraction of the cell cycle decreased in MSCs along with the aging process. At the same time, SA-β-gal+ levels increased, especially in the aged mice MSCs. When induced to be osteogenic, Osx gene expression and ALP activity declined in the mid-age and aged mice MSCs, while OCN protein secretion deteriorated in the aged mice MSCs. Conclusions These findings demonstrate that mouse MSCs changed with their proliferation and osteo-differentiation abilities at different aging stages, and that Bmal1 is related to the normal aging process in MSCs. PMID:22457671

  12. A Semantic Graph Query Language

    SciTech Connect

    Kaplan, I L

    2006-10-16

    Semantic graphs can be used to organize large amounts of information from a number of sources into one unified structure. A semantic query language provides a foundation for extracting information from the semantic graph. The graph query language described here provides a simple, powerful method for querying semantic graphs.

  13. A Defense of Semantic Minimalism

    ERIC Educational Resources Information Center

    Kim, Su

    2012-01-01

    Semantic Minimalism is a position about the semantic content of declarative sentences, i.e., the content that is determined entirely by syntax. It is defined by the following two points: "Point 1": The semantic content is a complete/truth-conditional proposition. "Point 2": The semantic content is useful to a theory of…

  14. Isotopic constraints on the age and early differentiation of the Earth.

    PubMed

    McCulloch, M T

    1996-03-01

    The Earth's age and early differentiation history are re-evaluated using updated isotopic constraints. From the most primitive terrestrial Pb isotopic compositions found at Isua Greenland, and the Pilbara of Western Australia, combined with precise geochronology of these localities, an age 4.49 +/- 0.02 Ga is obtained. This is interpreted as the mean age of core formation as U/Pb is fractionated due to sequestering of Pb into the Earth's core. The long-lived Rb-Sr isotopic system provides constraints on the time interval for the accretion of the Earth as Rb underwent significant depletion by volatile loss during accretion of the Earth or its precursor planetesimals. A primitive measured 87Sr/86Sr initial ratio of 0.700502 +/- 10 has been obtained for an early Archean (3.46 Ga) barite from the Pilbara Block of Western Australia. Using conservative models for the evolution of Rb/Sr in the early Archean mantle allows an estimate to be placed on the Earth's initial Sr ratio at approximately 4.50 Ga, of 0.69940 +/- 10. This is significantly higher than that measured for the Moon (0.69900 +/- 2) or in the achondrite, Angra dos Reis (0.69894 +/- 2) and for a Rb/Sr ratio of approximately 1/2 of chondrites corresponds to a mean age for accretion of the Earth of 4.48 + /- 0.04 Ga. The now extinct 146Sm-142Nd (T1/2(146)=103 l0(6)yrs) combined with the long-lived 147Sm-143Nd isotopic systematics can also be used to provide limits on the time of early differentiation of the Earth. High precision analyses of the oldest (3.8-3.9 Ga) Archean gneisses from Greenland (Amitsoq and Akilia gneisses), and Canada (Acasta gneiss) do not show measurable (> +/- l0ppm) variations of 142Nd, in contrast to the 33 ppm 142Nd excess reported for an Archean sample. The general lack of 142Nd variations, combined with the presence of highly positive epsilon 143 values (+4.0) at 3.9 Ga, indicates that the record of large-scale Sm/Nd fractionation events was not preserved in the early-Earth from 4

  15. Lethal Forethought: Delayed Reward Discounting Differentiates High- and Low-Lethality Suicide Attempts in Old Age

    PubMed Central

    Dombrovski, Alexandre Y.; Szanto, Katalin; Siegle, Greg J.; Wallace, Meredith L.; Forman, Steven D.; Sahakian, Barbara; Reynolds, Charles F.; Clark, Luke

    2011-01-01

    Background The decision to commit suicide may be impulsive, but lethal suicidal acts often involve planning and forethought. People who attempt suicide make disadvantageous decisions in other contexts, but nothing is known about the way they decide about the future. Can the willingness to postpone future gratification differentiate between individuals prone to serious, premeditated and less serious, unplanned suicidal acts? Methods Four groups of depressed participants aged 60+ made choices between smaller immediate and larger delayed monetary rewards: 15 who made high-lethality suicide attempts, 14 who made low-lethality suicide attempts, 12 who seriously contemplated suicide, and 42 people with depression but no history of suicidal thoughts. The reference group was 31 psychiatrically healthy elders. Results Individuals who had made low-lethality attempts displayed an exaggerated preference for immediate rewards compared to non-suicidal depressed and healthy controls. Those who had carried out high-lethality suicide attempts were more willing to delay future rewards, compared to low-lethality attempters. Better planned suicide attempts were also associated with willingness to wait for larger rewards. These effects were unchanged after accounting for education, global cognitive function, substance use disorders, psychotropic medications, and possible brain injury from attempts. Discount rates were correlated with having debt but were not significantly associated with income, hopelessness, depressive severity, premorbid IQ, age at first attempt, or choice of violent means. Conclusions While clinicians often focus on impulsivity in patients at risk for suicide, these data suggest that identifying biological characteristics and treatments for non-impulsive suicidal older people may be even more important. PMID:21329911

  16. Olfactory memory in the old and very old: relations to episodic and semantic memory and APOE genotype.

    PubMed

    Larsson, Maria; Hedner, Margareta; Papenberg, Goran; Seubert, Janina; Bäckman, Lars; Laukka, Erika J

    2016-02-01

    The neuroanatomical organization that underlies olfactory memory is different from that of other memory types. The present work examines olfactory memory in an elderly population-based sample (Swedish National Study on Aging and Care in Kungsholmen) aged 60-100 years (n = 2280). We used structural equation modeling to investigate whether olfactory memory in old age is best conceptualized as a distinct category, differentiated from episodic and semantic memory. Further, potential olfactory dedifferentiation and genetic associations (APOE) to olfactory function in late senescence were investigated. Results are in support of a 3-factor solution where olfactory memory, as indexed by episodic odor recognition and odor identification, is modeled separately from episodic and semantic memory for visual and verbal information. Increasing age was associated with poorer olfactory memory performance, and observed age-related deficits were further exacerbated for carriers of the APOE ε4 allele; these effects tended to be larger for olfactory memory compared to episodic and semantic memory pertaining to other sensory systems (vision, auditory). Finally, stronger correlations between olfactory and episodic memory, indicating dedifferentiation, were observed in the older age groups.

  17. Non-linear patterns in age-related DNA methylation may reflect CD4(+) T cell differentiation.

    PubMed

    Johnson, Nicholas D; Wiener, Howard W; Smith, Alicia K; Nishitani, Shota; Absher, Devin M; Arnett, Donna K; Aslibekyan, Stella; Conneely, Karen N

    2017-04-07

    DNA methylation (DNAm) is an important epigenetic process involved in the regulation of gene expression. While many studies have identified thousands of loci associated with age, few have differentiated between linear and non-linear DNAm trends with age. Non-linear trends could indicate early- or late-life gene regulatory processes. Using data from the Illumina 450K array on 336 human peripheral blood samples, we identified 21 CpG sites that associated with age (P<1.03E-7) and exhibited changing rates of DNAm change with age (P<1.94E-6). For two of these CpG sites (cg07955995 and cg22285878), DNAm increased with age at an increasing rate, indicating that differential DNAm was greatest among elderly individuals. We observed significant replication for both CpG sites (P<5.0E-8) in a second set of peripheral blood samples. In 8 of 9 additional datasets comprising samples of monocytes, T cell subtypes, and brain tissue, we observed a pattern directionally consistent with DNAm increasing with age at an increasing rate, which was nominally significant in the three largest datasets (4.3E-15differentiation via the repression of FOXP3. These findings may suggest a possible role for cg07955995 and cg22285878 in immunosenescence.

  18. Electrical Cell-Substrate Impedance Spectroscopy Can Monitor Age-Grouped Human Adipose Stem Cell Variability During Osteogenic Differentiation.

    PubMed

    Nordberg, Rachel C; Zhang, Jianlei; Griffith, Emily H; Frank, Matthew W; Starly, Binil; Loboa, Elizabeth G

    2017-02-01

    Human adipose stem cells (hASCs) are an attractive cell source for bone tissue engineering applications. However, a critical issue to be addressed before widespread hASC clinical translation is the dramatic variability in proliferative capacity and osteogenic potential among hASCs isolated from different donors. The goal of this study was to test our hypothesis that electrical cell-substrate impedance spectroscopy (ECIS) could track complex bioimpedance patterns of hASCs throughout proliferation and osteogenic differentiation to better understand and predict variability among hASC populations. Superlots composed of hASCs from young (aged 24-36 years), middle-aged (aged 48-55 years), and elderly (aged 60-81 years) donors were seeded on gold electrode arrays. Complex impedance measurements were taken throughout proliferation and osteogenic differentiation. During osteogenic differentiation, four impedance phases were identified: increase, primary stabilization, drop phase, and secondary stabilization. Matrix deposition was first observed 48-96 hours after the impedance maximum, indicating, for the first time, that ECIS can identify morphological changes that correspond to late-stage osteogenic differentiation. The impedance maximum was observed at day 10.0 in young, day 6.1 in middle-aged, and day 1.3 in elderly hASCs, suggesting that hASCs from younger donors require a longer time to differentiate than do hASCs from older donors, but young hASCs proliferated more and accreted more calcium long-term. This is the first study to use ECIS to predict osteogenic potential of multiple hASC populations and to show that donor age may temporally control onset of osteogenesis. These findings could be critical for development of patient-specific bone tissue engineering and regenerative medicine therapies. Stem Cells Translational Medicine 2017;6:502-511.

  19. Early-age heat exposure affects skeletal muscle satellite cell proliferation and differentiation in chicks.

    PubMed

    Halevy, O; Krispin, A; Leshem, Y; McMurtry, J P; Yahav, S

    2001-07-01

    Exposure of young chicks to thermal conditioning (TC; i.e., 37 degrees C for 24 h) resulted in significantly improved body and muscle growth at a later age. We hypothesized that TC causes an increase in satellite cell proliferation, necessary for further muscle hypertrophy. An immediate increase was observed in satellite cell DNA synthesis in culture and in vivo in response to TC of 3-day-old chicks to levels that were significantly higher than those of control chicks. This was accompanied by a marked induction of insulin-like growth factor-I (IFG-I), but not hepatocyte growth factor in the breast muscle. No significant difference between treatments in plasma IGF-I levels was observed. A marked elevation in muscle regulatory factors on day 5, followed by a decline in cell proliferation on day 6 together with continuous high levels of IGF-I in the TC chick muscle may indicate accelerated cell differentiation. These data suggest a central role for IGF-I in the immediate stimulation of satellite cell myogenic processes in response to heat exposure.

  20. Smad2 isoforms are differentially expressed during mouse brain development and aging.

    PubMed

    Ueberham, Uwe; Lange, Peggy; Ueberham, Elke; Brückner, Martina K; Hartlage-Rübsamen, Maike; Pannicke, Thomas; Rohn, Susanne; Cross, Michael; Arendt, Thomas

    2009-08-01

    Smad2 and Smad3 are central molecules of the TGFbeta and activin receptor complex mediated intracellular signaling pathway. They function as important transcription factors playing essential roles in brain development. Interestingly they are also known to be involved in the pathogenesis of various neurological disorders (including Alzheimer's disease). Due to structural differences in the N-terminal Mad homology domain 1, Smad2 and Smad3 differ in their ability to bind DNA directly. A splice form of Smad2 lacking exon3, Smad2(Deltaexon3), assumes features of Smad3, in that it can directly bind to DNA resulting in a functional hybrid of Smad2 and Smad3 properties. There is very little information available on the expression of Smad2 isoforms in the brain. We report here that Smad2(Deltaexon3) is the most abundant of the two Smad2 isoforms in mouse brain and that Smad expression pattern alters during development and aging. Neuronal expression of Smad2(Deltaexon3) was confirmed by a single-cell PCR approach. Moreover, Smad2(Deltaexon3) predominates in the nuclear fraction of neurons, suggesting special function during brain differentiation. Our data indicate that there may be a specific role for Smad2(Deltaexon3) in neurons.

  1. Simultaneous Differential Scanning Calorimetry and Thermogravimetric Analysis of Portland Cement as a Function of Age

    NASA Astrophysics Data System (ADS)

    Trník, Anton; Scheinherrová, Lenka; Kulovaná, Tereza; Černý, Robert

    2016-01-01

    We study the hydration and pozzolanic reactions of an ordinary Portland cement as a function of age, using the differential scanning calorimetry and thermogravimetry. The measurements are done for 2 days, 7 days, 28 days, 90 days, 180 days, and 360 days cured samples in order to monitor the rate of hydration. The investigation is performed in the temperature range from 25° C to 1000° C with a heating rate 5° C {\\cdot} min^{-1} in an argon atmosphere. The temperature, enthalpy, and mass change during the decomposition of calcium silicate hydrate gels, ettringite, portlandite, vaterite, and calcite are determined, and the changes in the portlandite amount are estimated in dependence on the time of hydration. We found out that the temperature and enthalpy of liberation of physically bound water, C-S-H gels and ettringite decomposition (all occurring from 50° C to 250° C) and Portlandite decomposition (420° C to 530° C) decrease with hydration time of studied samples. On the other hand, vaterite and calcite decomposition (530° C to 850° C) the temperature varies and the enthalpy increases with hydration time of samples.

  2. Differentiating School-Aged Children with and without Language Impairment Using Tense and Grammaticality Measures from a Narrative Task

    ERIC Educational Resources Information Center

    Guo, Ling-Yu; Schneider, Phyllis

    2016-01-01

    Purpose: To determine the diagnostic accuracy of the finite verb morphology composite (FVMC), number of errors per C-unit (Errors/CU), and percent grammatical C-units (PGCUs) in differentiating school-aged children with language impairment (LI) and those with typical language development (TL). Method: Participants were 61 six-year-olds (50 TL, 11…

  3. Sex Differences in Latent Cognitive Abilities Ages 5 to 17: Evidence from the Differential Ability Scales--Second Edition

    ERIC Educational Resources Information Center

    Keith, Timothy Z.; Reynolds, Matthew R.; Roberts, Lisa G.; Winter, Amanda L.; Austin, Cynthia A.

    2011-01-01

    Sex differences in the latent general and broad cognitive abilities underlying the Differential Ability Scales, Second Edition were investigated for children and youth ages 5 through 17. Multi-group mean and covariance structural equation modeling was used to investigate sex differences in latent cognitive abilities as well as changes in these…

  4. The Differential Effects of Age and First Grade Schooling on the Development of Infralogical and Logico-Mathematical Concrete Operations

    ERIC Educational Resources Information Center

    Cahan, Sorel; Greenbaum, Charles; Artman, Lavee; Deluya, Nilly; Gappel-Gilon, Yael

    2008-01-01

    Using the ''between-grade levels'' regression discontinuity design, this study examined the hypothesized differential sensitivity of logico-mathematical (LM) and infralogical (IL) operational tasks to the effects of chronological age and first grade schooling in a sample of 580 1st and 2nd grade Israeli children. The results indicate that the…

  5. Trusting Crowdsourced Geospatial Semantics

    NASA Astrophysics Data System (ADS)

    Goodhue, P.; McNair, H.; Reitsma, F.

    2015-08-01

    The degree of trust one can place in information is one of the foremost limitations of crowdsourced geospatial information. As with the development of web technologies, the increased prevalence of semantics associated with geospatial information has increased accessibility and functionality. Semantics also provides an opportunity to extend indicators of trust for crowdsourced geospatial information that have largely focused on spatio-temporal and social aspects of that information. Comparing a feature's intrinsic and extrinsic properties to associated ontologies provides a means of semantically assessing the trustworthiness of crowdsourced geospatial information. The application of this approach to unconstrained semantic submissions then allows for a detailed assessment of the trust of these features whilst maintaining the descriptive thoroughness this mode of information submission affords. The resulting trust rating then becomes an attribute of the feature, providing not only an indication as to the trustworthiness of a specific feature but is able to be aggregated across multiple features to illustrate the overall trustworthiness of a dataset.

  6. Growth differentiation factor 11 (GDF11) - a promising anti-ageing factor - is highly concentrated in platelets.

    PubMed

    Bueno, J L; Ynigo, M; de Miguel, C; Gonzalo-Daganzo, R M; Richart, A; Vilches, C; Regidor, C; García-Marco, J A; Flores-Ballester, E; Cabrera, J R

    2016-11-01

    Recent research suggests that growth differentiation factor 11 (GDF11) could reverse age-related diseases and that its blood concentration decreases with age. This poses plasma from young donors as a therapeutic GDF11 source to treat age-related diseases. In addition, the tissue source of circulating GDF11 remains unknown. We analysed GDF11 levels in paired samples of serum, plasma and platelet lysate (PL) from 23 volunteers. Plasma and PL were collected by plateletpheresis. Here, we show that GDF11 is highly concentrated in platelets and that the circulating levels reported in previous studies could be biased as a result of serum sample manipulation.

  7. Impaired haematopoietic stem cell differentiation and enhanced skewing towards myeloid progenitors in aged caspase-2-deficient mice

    PubMed Central

    Dawar, Swati; Shahrin, Nur Hezrin; Sladojevic, Nikolina; D'Andrea, Richard J; Dorstyn, Loretta; Hiwase, Devendra K; Kumar, Sharad

    2016-01-01

    The apoptotic cysteine protease caspase-2 has been shown to suppress tumourigenesis in mice and its reduced expression correlates with poor prognosis in some human malignancies. Caspase-2-deficient mice develop normally but show ageing-related traits and, when challenged by oncogenic stimuli or certain stress, show enhanced tumour development, often accompanied by extensive aneuploidy. As stem cells are susceptible to acquiring age-related functional defects because of their self-renewal and proliferative capacity, we examined whether loss of caspase-2 promotes such defects with age. Using young and aged Casp2−/− mice, we demonstrate that deficiency of caspase-2 results in enhanced aneuploidy and DNA damage in bone marrow (BM) cells with ageing. Furthermore, we demonstrate for the first time that caspase-2 loss results in significant increase in immunophenotypically defined short-term haematopoietic stem cells (HSCs) and multipotent progenitors fractions in BM with a skewed differentiation towards myeloid progenitors with ageing. Caspase-2 deficiency leads to enhanced granulocyte macrophage and erythroid progenitors in aged mice. Colony-forming assays and long-term culture-initiating assay further recapitulated these results. Our results provide the first evidence of caspase-2 in regulating HSC and progenitor differentiation, as well as aneuploidy, in vivo. PMID:27906175

  8. Functional comparison of chronological and in vitro aging: differential role of the cytoskeleton and mitochondria in mesenchymal stromal cells.

    PubMed

    Geissler, Sven; Textor, Martin; Kühnisch, Jirko; Könnig, Delia; Klein, Oliver; Ode, Andrea; Pfitzner, Tilman; Adjaye, James; Kasper, Grit; Duda, Georg N

    2012-01-01

    Mesenchymal stromal cells (MSCs) are of high relevance for the regeneration of mesenchymal tissues such as bone and cartilage. The promising role of MSCs in cell-based therapies and tissue engineering appears to be limited due to a decline of their regenerative potential with increasing donor age, their limited availability in human tissues and the need of in vitro expansion prior to treatment. We therefore aimed to determine to which degree in vitro aging and chronological aging may be similar processes or if in vitro culture-related changes at the cellular and molecular level are at least altered as a function of donor age. For that purpose we established MSCs cultures from young (yMSCs) and aged (aMSCs) rats that were cultured for more than 100 passages. These long-term MSCs cultures were non-tumorigenic and exhibited similar surface marker patterns as primary MSCs of passage 2. During in vitro expansion, but not during chronological aging, MSCs progressively lose their progenitor characteristics, e.g., complete loss of osteogenic differentiation potential, diminished adipogenic differentiation, altered cell morphology and increased susceptibility towards senescence. Transcriptome analysis revealed that long-term in vitro MSCs cultivation leads to down-regulation of genes involved in cell differentiation, focal adhesion organization, cytoskeleton turnover and mitochondria function. Accordingly, functional analysis demonstrated altered mitochondrial morphology, decreased antioxidant capacities and elevated ROS levels in long-term cultivated yMSCs as well as aMSCs. Notably, only the MSC migration potential and their antioxidative capacity were altered by in vitro as well as chronological aging. Based on specific differences observed between the impact of chronological and in vitro MSC aging we conclude that both are distinct processes.

  9. Exploring the Utility of a School-Age Narrative Microstructure Index: Proportion of Restricted Utterances

    ERIC Educational Resources Information Center

    Jerger, Sara; Thorne, John C.

    2016-01-01

    Purpose: This research attempted to replicate Hoffman's 2009 finding that the proportion of narrative utterances with semantic or syntactic errors (i.e., = 14% "restricted utterances") can differentiate school-age children with typical development from those with language impairment with a sensitivity of 83% and specificity of 88%.…

  10. Assessing Changes in Attitudes about Aging: Personal Reflections and a Standardized Measure.

    ERIC Educational Resources Information Center

    O'Hanlon, Ann M.; Brookover, B. Cecile

    2002-01-01

    Sophomore (n=31) and senior (n=24) gerontology students completed the Aging Semantic Differential at the beginning of the semester and after conducting life-history interviews with older adults. Significant positive attitude changes resulted; the interviews were specifically cited as influencing changes. (Contains 33 references.) (SK)

  11. Aging Reduces an ERRalpha-Directed Mitochondrial Glutaminase Expression Suppressing Glutamine Anaplerosis and Osteogenic Differentiation of Mesenchymal Stem Cells.

    PubMed

    Huang, Tongling; Liu, Renzhong; Fu, Xuekun; Yao, Dongsheng; Yang, Meng; Liu, Qingli; Lu, William W; Wu, Chuanyue; Guan, Min

    2017-02-01

    Aging deteriorates osteogenic capacity of mesenchymal stem/stromal cells (MSCs), contributing to imbalanced bone remodeling and osteoporosis. Glutaminase (Gls) catabolizes glutamine into glutamate at the first step of mitochondrial glutamine (Gln)-dependent anaplerosis which is essential for MSCs upon osteogenic differentiation. Estrogen-related receptor α (ERRα) regulates genes required for mitochondrial function. Here, we found that ERRα and Gls are upregulated by osteogenic induction in human MSCs (hMSCs). In contrast, osteogenic differentiation capacity and glutamine consumption of MSCs, as well as ERRα, Gls and osteogenic marker genes are significantly reduced with age. We demonstrated that ERRα binds to response elements on Gls promoter and affects glutamine anaplerosis through transcriptional induction of Gls. Conversely, mTOR inhibitor rapamycin, ERRα inverse agonist compound 29 or Gls inhibitor BPTES leads to reduced Gln anaplerosis and deteriorated osteogenic differentiation of hMSCs. Importantly, overexpression of ERRα or Gls restored impairment by these inhibitors. Finally, we proved that compensated ERRα or Gls expression indeed potentiated Gln anaplerosis and osteogenic capability of elderly mice MSCs in vitro. Together, we establish that Gls is a novel ERRα target gene and ERRα/Gls signaling pathway plays an important role in osteogenic differentiation of MSCs, providing new sights into novel regenerative therapeutics development. Our findings suggest that restoring age-related mitochondrial Gln-dependent anaplerosis may be beneficial for degenerative bone disorders such as osteoporosis. Stem Cells 2017;35:411-424.

  12. Single-cell RNA-seq reveals changes in cell cycle and differentiation programs upon aging of hematopoietic stem cells.

    PubMed

    Kowalczyk, Monika S; Tirosh, Itay; Heckl, Dirk; Rao, Tata Nageswara; Dixit, Atray; Haas, Brian J; Schneider, Rebekka K; Wagers, Amy J; Ebert, Benjamin L; Regev, Aviv

    2015-12-01

    Both intrinsic cell state changes and variations in the composition of stem cell populations have been implicated as contributors to aging. We used single-cell RNA-seq to dissect variability in hematopoietic stem cell (HSC) and hematopoietic progenitor cell populations from young and old mice from two strains. We found that cell cycle dominates the variability within each population and that there is a lower frequency of cells in the G1 phase among old compared with young long-term HSCs, suggesting that they traverse through G1 faster. Moreover, transcriptional changes in HSCs during aging are inversely related to those upon HSC differentiation, such that old short-term (ST) HSCs resemble young long-term (LT-HSCs), suggesting that they exist in a less differentiated state. Our results indicate both compositional changes and intrinsic, population-wide changes with age and are consistent with a model where a relationship between cell cycle progression and self-renewal versus differentiation of HSCs is affected by aging and may contribute to the functional decline of old HSCs.

  13. Varying Teacher Expectations and Standards: Curriculum Differentiation in the Age of Standards-Based Reform

    ERIC Educational Resources Information Center

    Harris, Donna M.

    2012-01-01

    Ability grouping and tracking have been a major focus in educational research because of its role in promoting curriculum differentiation. However, there has been limited attention to how this differentiation occurs in contemporary schools involved with reform efforts including those focused on subject specific academic standards designed to…

  14. From lymphopoiesis to plasma cells differentiation, the age-related modifications of B cell compartment are influenced by "Inflamm-Ageing".

    PubMed

    Bulati, Matteo; Caruso, Calogero; Colonna-Romano, Giuseppina

    2017-04-07

    Ageing is a complex process characterized by a general decline in physiological functions with increasing morbidity and mortality. The most important aspect of ageing is the chronic inflammatory status, named "inflamm-ageing", strictly associated with the deterioration of the immune function, termed "immunosenescence". Both are causes of increased susceptibility of elderly to infectious diseases, cancer, dementia, cardiovascular diseases and autoimmunity, and of a decreased response to vaccination. It has been widely demonstrated that ageing has a strong impact on the remodelling of the B cell branch of immune system. The first evident effect is the significant decrease in circulating B cells, primarily due to the reduction of new B cell coming from bone marrow (BM) progenitors, as inflammation directly impacts on B lymphopoiesis. Besides, in aged individuals, there is a shift from naïve to memory immunoglobulins production, accompanied by the impaired ability to produce high affinity protective antibodies against newly encountered antigens. This is accompanied by the increase of expanded clones of B cells, which correlates with poor health status. Age-related modifications also occur in naïve/memory B cells subsets. Indeed, in the elderly, there is a reduction of naïve B cells, accompanied by the expansion of memory B cells that show a senescence-associated phenotype. Finally, elderly show the impaired ability of memory B cells to differentiate into plasma cells. It can be concluded that inflammation is the leading cause of the age-related impairment of B cell compartment, which play certainly a key role in the development of age-related diseases. This makes study of B cells in the aged an important tool for monitoring immunosenescence, chronic inflammatory disorders and the effectiveness of vaccines or pharmacological therapies.

  15. Non-semantic contributions to "semantic" redundancy gain.

    PubMed

    Shepherdson, Peter; Miller, Jeff

    2016-01-01

    Recently, two groups of researchers have reported redundancy gains (enhanced performance with multiple, redundant targets) in tasks requiring semantic categorization. Here we report two experiments aimed at determining whether the gains found by one of these groups resulted from some form of semantic coactivation. We asked undergraduate psychology students to complete choice RT tasks requiring the semantic categorization of visually presented words, and compared performance with redundant targets from the same semantic category to performance with redundant targets from different semantic categories. If the redundancy gains resulted from the combination of information at a semantic level, they should have been greater in the former than the latter situation. However, our results showed no significant differences in redundancy gain (for latency and accuracy) between same-category and different-category conditions, despite gains appearing in both conditions. Thus, we suggest that redundancy gain in the semantic categorization task may result entirely from statistical facilitation or combination of information at non-semantic levels.

  16. Consolidated findings from 6 years research on the age-differentiated design of human-computer interaction.

    PubMed

    Vetter, Sebastian; Bützler, Jennifer; Jochems, Nicole; Schlick, Christopher M

    2012-01-01

    The fast aging of many western and eastern societies and their increasing reliance on information technology create a compelling need to reconsider older users' interactions with computers. This paper summarizes the results of 6 years of research on the age-differentiated design of human-computer interaction. The well-known model of human information processing served as the theoretical framework. The model components ''sensory processing'', ''perception'', ''working memory'', ''decision and response selection'' and ''response execution'' were analyzed exemplarily in task settings on project management. In seven empirical studies with a total number of 405 participants between 20 and 77 years the human-computer interaction was analyzed regarding effectiveness, efficiency and user satisfaction. For most but not all studies the results reveal that age-induced differences in human-computer interaction can best be compensated by an ergonomic ''design for all''. In some cases however an age-specific approach is favorable.

  17. Sex differences in angiotensin II responses contribute to a differential regulation of cox-mediated vascular dysfunction during aging.

    PubMed

    Costa, Gustavo; Garabito, Manel; Jiménez-Altayó, Francesc; Onetti, Yara; Sabate, Manel; Vila, Elisabet; Dantas, Ana Paula

    2016-12-01

    Aging is a cardiovascular risk factor partially related to activation of the Renin-Angiotensin System (RAS). RAS activation is also influenced by sex. In this regard, our study aims to determine whether sex-associated differences in RAS contribute to a differential regulation of vascular aging and associated dysfunction. Male and female outbreed CD-1 mice were studied at 3 and 12months of age (M). Contribution of RAS was determined by treating mice from 3M to 12M with the AngII type 1 receptor blocker losartan (0.6g/L in the drinking water). At 12M, contractions to AngII were higher in males compared to females (P<0.05). This effect was paralleled by a decrease in AngII type 2 receptors in 12M males. Aging also diminished ACh relaxation in males, but did not modify female responses. Treatment of aortas with indomethacin (10μM) restored the impaired endothelium-dependent relaxation in 12M males, suggesting an increase of cyclooxygenase (COX)-derived vasoconstrictors in aged males. Chronic treatment of mice with losartan also improved endothelium-dependent relaxation. Besides, losartan significantly decreased COX-2 expression and activity in 12M male, with a minor effect in aged females. Aging increases AngII contraction and induces endothelial dysfunction differently in males and females. In aged males, RAS contributed to increased COX-2 expression and activity, which in turn may lead to vascular dysfunction.

  18. Knowledge Representation Issues in Semantic Graphs for Relationship Detection

    SciTech Connect

    Barthelemy, M; Chow, E; Eliassi-Rad, T

    2005-02-02

    An important task for Homeland Security is the prediction of threat vulnerabilities, such as through the detection of relationships between seemingly disjoint entities. A structure used for this task is a ''semantic graph'', also known as a ''relational data graph'' or an ''attributed relational graph''. These graphs encode relationships as typed links between a pair of typed nodes. Indeed, semantic graphs are very similar to semantic networks used in AI. The node and link types are related through an ontology graph (also known as a schema). Furthermore, each node has a set of attributes associated with it (e.g., ''age'' may be an attribute of a node of type ''person''). Unfortunately, the selection of types and attributes for both nodes and links depends on human expertise and is somewhat subjective and even arbitrary. This subjectiveness introduces biases into any algorithm that operates on semantic graphs. Here, we raise some knowledge representation issues for semantic graphs and provide some possible solutions using recently developed ideas in the field of complex networks. In particular, we use the concept of transitivity to evaluate the relevance of individual links in the semantic graph for detecting relationships. We also propose new statistical measures for semantic graphs and illustrate these semantic measures on graphs constructed from movies and terrorism data.

  19. Development of Planning Abilities in Normal Aging: Differential Effects of Specific Cognitive Demands

    ERIC Educational Resources Information Center

    Köstering, Lena; Stahl, Christoph; Leonhart, Rainer; Weiller, Cornelius; Kaller, Christoph P.

    2014-01-01

    In line with the frontal hypothesis of aging, the ability to plan ahead undergoes substantial change during normal aging. Although impairments on the Tower of London planning task were reported earlier, associations between age-related declines and specific cognitive demands on planning have not been studied. Here we investigated the impact of…

  20. The Anti-Aging and Tumor Suppressor Protein Klotho Enhances Differentiation of a Human Oligodendrocytic Hybrid Cell Line

    PubMed Central

    Chen, Ci-Di; Liang, Jennifer; Hixson, Kathryn; Zeldich, Ella; Abraham, Carmela R.

    2016-01-01

    Klotho functions as an aging suppressor, which, in mice, extends lifespan when overexpressed and accelerates development of aging-like phenotypes when disrupted. Klotho is mainly expressed in brain and kidney and is secreted into the serum and CSF. We have previously shown that Klotho is reduced in brains of old monkeys, rats, and mice. We further reported the ability of Klotho to enhance oligodendrocyte differentiation and myelination. Here, we examined the signaling pathways induced by Klotho in MO3.13, a human oligodendrocytic hybrid cell line. We show that exogenous Klotho affects the ERK and Akt signaling pathways, decreases the proliferative abilities and enhances differentiation of MO3.13 cells. Furthermore, microarray analysis of Klotho-treated MO3.13 cells reveals a massive change in gene expression with 80 % of the differentially expressed genes being downregulated. Using gene set enrichment analysis, we predicted potential transcription factors involved in regulating Klotho-treated MO3.13 cells and found that these cells are highly enriched in the gene sets, that are similarly observed in cancer, cardiovascular disease, stress, aging, and hormone-related chemical and genetic perturbations. Since Klotho is downregulated in all brain tumors tested to date, enhancing Klotho has therapeutic potential for treating brain and other malignancies. PMID:24907942

  1. Temporal Representation in Semantic Graphs

    SciTech Connect

    Levandoski, J J; Abdulla, G M

    2007-08-07

    A wide range of knowledge discovery and analysis applications, ranging from business to biological, make use of semantic graphs when modeling relationships and concepts. Most of the semantic graphs used in these applications are assumed to be static pieces of information, meaning temporal evolution of concepts and relationships are not taken into account. Guided by the need for more advanced semantic graph queries involving temporal concepts, this paper surveys the existing work involving temporal representations in semantic graphs.

  2. Does aging impair first impression accuracy? Differentiating emotion recognition from complex social inferences.

    PubMed

    Krendl, Anne C; Rule, Nicholas O; Ambady, Nalini

    2014-09-01

    Young adults can be surprisingly accurate at making inferences about people from their faces. Although these first impressions have important consequences for both the perceiver and the target, it remains an open question whether first impression accuracy is preserved with age. Specifically, could age differences in impressions toward others stem from age-related deficits in accurately detecting complex social cues? Research on aging and impression formation suggests that young and older adults show relative consensus in their first impressions, but it is unknown whether they differ in accuracy. It has been widely shown that aging disrupts emotion recognition accuracy, and that these impairments may predict deficits in other social judgments, such as detecting deceit. However, it is unclear whether general impression formation accuracy (e.g., emotion recognition accuracy, detecting complex social cues) relies on similar or distinct mechanisms. It is important to examine this question to evaluate how, if at all, aging might affect overall accuracy. Here, we examined whether aging impaired first impression accuracy in predicting real-world outcomes and categorizing social group membership. Specifically, we studied whether emotion recognition accuracy and age-related cognitive decline (which has been implicated in exacerbating deficits in emotion recognition) predict first impression accuracy. Our results revealed that emotion recognition accuracy did not predict first impression accuracy, nor did age-related cognitive decline impair it. These findings suggest that domains of social perception outside of emotion recognition may rely on mechanisms that are relatively unimpaired by aging.

  3. Semantic Search of Web Services

    ERIC Educational Resources Information Center

    Hao, Ke

    2013-01-01

    This dissertation addresses semantic search of Web services using natural language processing. We first survey various existing approaches, focusing on the fact that the expensive costs of current semantic annotation frameworks result in limited use of semantic search for large scale applications. We then propose a vector space model based service…

  4. Comparative clinicopathological and outcome analysis of differentiated thyroid cancer in Saudi patients aged below 60 years and above 60 years

    PubMed Central

    AL-Qahtani, Khalid Hussain; Tunio, Mutahir A; Asiri, Mushabbab Al; Bayoumi, Yasser; Balbaid, Ali; Aljohani, Naji J; Fatani, Hanadi

    2016-01-01

    Introduction The aim of this study was to evaluate the treatment outcomes of differentiated thyroid cancer in Saudi patients aged above 60 years. Materials and methods Comparative analysis was performed in 252 patients aged 46–60 years (Group A) and 118 patients aged above 60 years (Group B), who had thyroidectomy, radioactive iodine-131, and thyroid-stimulating hormone suppression therapy between July 2000 and December 2012. Different clinicopathological features, treatment, complications, disease-free survival, and overall survival rates were compared. Results Mean age of patients in Group A was 51.9 years (range: 46–60), and mean age of those in Group B was 68.6 years (range: 62–97). Group B patients had higher positive lymph nodes (43.2%), P=0.011. The frequency of extrathyroidal extension, multifocality, and lymphovascular space invasion was seen more in Group B than in Group A. Postsurgical complications (permanent hypoparathyroidism, bleeding, and wound infections) were also seen more in Group B (P=0.043, P=0.011, and P=0.021, respectively). Group B patients experienced more locoregional recurrences (11.0%, P=0.025); similarly, more distant metastases were observed in Group B (15.3%, P=0.003). The 10-year disease-free survival rates were 87.6% in Group A and 70.8% in Group B (P<0.0001). Conclusion Differentiated thyroid cancer in patients aged above 60 years are more aggressive biologically and associated with a worse prognosis, and the morbidity is significantly high as compared to patients aged below 60 years. PMID:27621604

  5. Growth Differentiation Factor 11 is a Circulating Factor that Reverses Age-Related Cardiac Hypertrophy

    PubMed Central

    Loffredo, Francesco S.; Steinhauser, Matthew L.; Jay, Steven M.; Gannon, Joseph; Pancoast, James R.; Yalamanchi, Pratyusha; Sinha, Manisha; Dall’Osso, Claudia; Khong, Danika; Shadrach, Jennifer L.; Miller, Christine M.; Singer, Britta S.; Stewart, Alex; Psychogios, Nikolaos; Gerszten, Robert E.; Hartigan, Adam J.; Kim, Mi-Jeong; Serwold, Thomas; Wagers, Amy J.; Lee, Richard T.

    2013-01-01

    Summary The most common form of heart failure occurs with normal systolic function and often involves cardiac hypertrophy in the elderly. To clarify the biological mechanisms that drive cardiac hypertrophy in aging, we tested the influence of circulating factors using heterochronic parabiosis, a surgical technique in which joining of animals of different ages leads to a shared circulation. After 4 weeks of exposure to the circulation of young mice, cardiac hypertrophy in old mice dramatically regressed, accompanied by reduced cardiomyocyte size and molecular remodeling. Reversal of age-related hypertrophy was not attributable to hemodynamic or behavioral effects of parabiosis, implicating a blood-borne factor. Using modified aptamer-based proteomics, we identified the TGFβ superfamily member GDF11 as a circulating factor in young mice that declines with age. Treatment of old mice to restore GDF11 to youthful levels recapitulated the effects of parabiosis and reversed age-related hypertrophy, revealing a new therapeutic opportunity for cardiac aging. PMID:23663781

  6. Differential Gene Expression Profiles Reflecting Macrophage Polarization in Aging and Periodontitis Gingival Tissues

    PubMed Central

    Gonzalez, O.A.; Novak, M.J.; Kirakodu, S.; Stromberg, A.; Nagarajan, R.; Huang, C.B.; Chen, K.C.; Orraca, L.; Martinez-Gonzalez, J.; Ebersole, J.L.

    2016-01-01

    SUMMARY Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1, M2) of these cells in inflammation, adaptive immune responses, and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a nonhuman primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3–23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent, and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7, TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype. PMID:26397131

  7. Differential Effects of Aging on Fore– and Hindpaw Maps of Rat Somatosensory Cortex

    PubMed Central

    David-Jürgens, Marianne; Churs, Lydia; Berkefeld, Thomas; Zepka, Roberto F.; Dinse, Hubert R.

    2008-01-01

    Getting older is associated with a decline of cognitive and sensorimotor abilities, but it remains elusive whether age-related changes are due to accumulating degenerational processes, rendering them largely irreversible, or whether they reflect plastic, adaptational and presumably compensatory changes. Using aged rats as a model we studied how aging affects neural processing in somatosensory cortex. By multi-unit recordings in the fore- and hindpaw cortical maps we compared the effects of aging on receptive field size and response latencies. While in aged animals response latencies of neurons of both cortical representations were lengthened by approximately the same amount, only RFs of hindpaw neurons showed severe expansion with only little changes of forepaw RFs. To obtain insight into parallel changes of walking behavior, we recorded footprints in young and old animals which revealed a general age-related impairment of walking. In addition we found evidence for a limb-specific deterioration of the hindlimbs that was not observed in the forelimbs. Our results show that age-related changes of somatosensory cortical neurons display a complex pattern of regional specificity and parameter-dependence indicating that aging acts rather selectively on cortical processing of sensory information. The fact that RFs of the fore- and hindpaws do not co-vary in aged animals argues against degenerational processes on a global scale. We therefore conclude that age-related alterations are composed of plastic-adaptive alterations in response to modified use and degenerational changes developing with age. As a consequence, age-related changes need not be irreversible but can be subject to amelioration through training and stimulation. PMID:18852896

  8. Differential effects of aging on fore- and hindpaw maps of rat somatosensory cortex.

    PubMed

    David-Jürgens, Marianne; Churs, Lydia; Berkefeld, Thomas; Zepka, Roberto F; Dinse, Hubert R

    2008-01-01

    Getting older is associated with a decline of cognitive and sensorimotor abilities, but it remains elusive whether age-related changes are due to accumulating degenerational processes, rendering them largely irreversible, or whether they reflect plastic, adaptational and presumably compensatory changes. Using aged rats as a model we studied how aging affects neural processing in somatosensory cortex. By multi-unit recordings in the fore- and hindpaw cortical maps we compared the effects of aging on receptive field size and response latencies. While in aged animals response latencies of neurons of both cortical representations were lengthened by approximately the same amount, only RFs of hindpaw neurons showed severe expansion with only little changes of forepaw RFs. To obtain insight into parallel changes of walking behavior, we recorded footprints in young and old animals which revealed a general age-related impairment of walking. In addition we found evidence for a limb-specific deterioration of the hindlimbs that was not observed in the forelimbs. Our results show that age-related changes of somatosensory cortical neurons display a complex pattern of regional specificity and parameter-dependence indicating that aging acts rather selectively on cortical processing of sensory information. The fact that RFs of the fore- and hindpaws do not co-vary in aged animals argues against degenerational processes on a global scale. We therefore conclude that age-related alterations are composed of plastic-adaptive alterations in response to modified use and degenerational changes developing with age. As a consequence, age-related changes need not be irreversible but can be subject to amelioration through training and stimulation.

  9. Differential Gene Expression Profiles Reflecting Macrophage Polarization in Aging and Periodontitis Gingival Tissues.

    PubMed

    Gonzalez, O A; Novak, M J; Kirakodu, S; Stromberg, A; Nagarajan, R; Huang, C B; Chen, K C; Orraca, L; Martinez-Gonzalez, J; Ebersole, J L

    2015-01-01

    Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1 and M2) of these cells in inflammation, adaptive immune responses and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a non-human primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3-23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7 and TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype.

  10. Semantator: semantic annotator for converting biomedical text to linked data.

    PubMed

    Tao, Cui; Song, Dezhao; Sharma, Deepak; Chute, Christopher G

    2013-10-01

    More than 80% of biomedical data is embedded in plain text. The unstructured nature of these text-based documents makes it challenging to easily browse and query the data of interest in them. One approach to facilitate browsing and querying biomedical text is to convert the plain text to a linked web of data, i.e., converting data originally in free text to structured formats with defined meta-level semantics. In this paper, we introduce Semantator (Semantic Annotator), a semantic-web-based environment for annotating data of interest in biomedical documents, browsing and querying the annotated data, and interactively refining annotation results if needed. Through Semantator, information of interest can be either annotated manually or semi-automatically using plug-in information extraction tools. The annotated results will be stored in RDF and can be queried using the SPARQL query language. In addition, semantic reasoners can be directly applied to the annotated data for consistency checking and knowledge inference. Semantator has been released online and was used by the biomedical ontology community who provided positive feedbacks. Our evaluation results indicated that (1) Semantator can perform the annotation functionalities as designed; (2) Semantator can be adopted in real applications in clinical and transactional research; and (3) the annotated results using Semantator can be easily used in Semantic-web-based reasoning tools for further inference.

  11. Differential expression of cathepsins K, S and V between young and aged Caucasian women skin epidermis.

    PubMed

    Sage, Juliette; De Quéral, Delphine; Leblanc-Noblesse, Emmanuelle; Kurfurst, Robin; Schnebert, Sylvianne; Perrier, Eric; Nizard, Carine; Lalmanach, Gilles; Lecaille, Fabien

    2014-01-01

    Cutaneous aging translates drastic structural and functional alterations in the extracellular matrix (ECM). Multiple mechanisms are involved, including changes in protease levels. We investigated the age-related protein expression and activity of cysteine cathepsins and the expression of two endogenous protein inhibitors in young and aged Caucasian women skin epidermis. Immunofluorescence studies indicate that the expression of cathepsins K, S and V, as well as cystatins A and M/E within keratinocytes is reduced in photoprotected skin of aged women. Furthermore, the overall endopeptidase activity of cysteine cathepsins in epidermis lysates decreased with age. Albeit dermal elastic fiber and laminin expression is reduced in aged skin, staining of nidogen-1, a key protein in BM assembly that is sensitive to proteolysis by cysteine, metallo- and serine proteases, has a similar pattern in both young and aged skin. Since cathepsins contribute to the hydrolysis and turnover of ECM/basement membrane components, the abnormal protein degradation and deposition during aging process may be related in part to a decline of lysosomal/endosomal cathepsin K, S and V activity.

  12. Excess body mass is associated with T cell differentiation indicative of immune aging in children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity has been associated with accelerated biological ageing and immunosenescence. As the prevalence of childhood obesity is increasing, we wanted to determine if associations between obesity and immunosenescence would manifest in children. We studied 123 Mexican American adolescents aged 10–14 (m...

  13. Ablations of ghrelin and ghrelin receptor exhibit differential metabolic phenotypes and thermogenic capacity during aging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is a hallmark of aging in many Western societies, and is a precursor to numerous serious age-related diseases. Ghrelin ("Ghrl"), via its receptor (growth hormone secretagogue receptor, GHS-R), is shown to stimulate GH secretion and appetite. Surprisingly, our previous studies showed that "Gh...

  14. Differential effects of blueberry polyphenols on age-associated neuroinflammation and cognition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Long-term effects of oxidative stress and inflammatory insults are thought to contribute to the decrements in cognitive performance seen in aging and neurodegenerative diseases. In previous studies, we have shown the beneficial effects of various dark-colored berry fruits in reversing age-related de...

  15. Differential Effect of Aging on Verbal and Visuo-Spatial Working Memory

    PubMed Central

    Kumar, Navnit; Priyadarshi, Brajesh

    2013-01-01

    Working memory (WM) declines with age. However it seems unclear, whether age related decline is more pronounced on verbal WM or on visuo-spatial WM. The present study compares the effect of aging on verbal and visuo-spatial modality of WM on native Hindi healthy speakers, in the age range of 40-to-above 80 years. It was found that normal aging affect both the verbal and visual working memory in similar way. Both modality declines with a similar rate up to 50–60 years and after 60 years relative saturation in span take place. Although verbal WM span is higher than visuo-spatial WM span, but no significant difference between verbal and visuo-spatial WM span were observed. PMID:23946892

  16. Effects of Semantic Predictability on Children's Preservation of a Phonemic Voice Contrast.

    ERIC Educational Resources Information Center

    Charles-Luce, Jan; Dressler, Kelly M.; Ragonese, Elvira

    1999-01-01

    Investigated the effects of semantic predictability on children's preservation of the /t/-/d/ phonemic voice contrast. Children in three age groups completed testing. Twelve adults acted as controls. There were age-related effects in the influence of semantic predictability on the preservation of a phonemic voice contrast. Differences produced by…

  17. Embedding of Semantic Predications.

    PubMed

    Cohen, Trevor; Widdows, Dominic

    2017-03-08

    This paper concerns the generation of distributed vector representations of biomedical concepts from structured knowledge, in the form of subject-relation-object triplets known as semantic predications. Specifically, we evaluate the extent to which a representational approach we have developed for this purpose previously, known as Predication-based Semantic Indexing (PSI), might benefit from insights gleaned from neural-probabilistic language models, which have enjoyed a surge in popularity in recent years as a means to generate distributed vector representations of terms from free text. To do so, we develop a novel neural-probabilistic approach to encoding predications, called Embedding of Semantic Predications (ESP), by adapting aspects of the Skipgram with Negative Sampling (SGNS) algorithm to this purpose. We compare ESP and PSI across a number of tasks including recovery of encoded information, estimation of semantic similarity and relatedness, and identification of potentially therapeutic and harmful relationships using both analogical retrieval and supervised learning. We find advantages for ESP in some, but not all of these tasks, revealing the contexts in which the additional computational work of neural-probabilistic modeling is justified.

  18. Semantically Grounded Briefings

    DTIC Science & Technology

    2005-12-01

    occurring relations. AeroText and consequently AeroDAML can be tailored to particular domains through training sessions with annotated corpuses...the complexities of semantic markup by using mnemonic names for URIs, hiding unnamed intermediate objects (represented by “ GenSym ” identifiers), and

  19. Semantic and Lexical Coherence.

    ERIC Educational Resources Information Center

    Fahnestock, Jeanne

    Helping students understand coherence in terms of the lexical ties and semantic relations possible between clauses and sentences formalizes an area of writing instruction that has been somewhat vague before and makes the process of creating a coherent paragraph less mysterious. Many students do not have the intuitive knowledge base for absorbing…

  20. Latent Semantic Analysis.

    ERIC Educational Resources Information Center

    Dumais, Susan T.

    2004-01-01

    Presents a literature review that covers the following topics related to Latent Semantic Analysis (LSA): (1) LSA overview; (2) applications of LSA, including information retrieval (IR), information filtering, cross-language retrieval, and other IR-related LSA applications; (3) modeling human memory, including the relationship of LSA to other…

  1. Semantic Web Development

    DTIC Science & Technology

    2006-09-01

    many documents are not expressible in logica at all, and many in logic but not in N3. However, we are building a system for which a prime goal is the...demonstrate that conventional logica programming tools are efficent and straightforwradly adapted to semantic web work. • Jena RDF toolkit now accepts N3 as

  2. Signaling pathways in aged T cells – a reflection of T cell differentiation, cell senescence and host environment

    PubMed Central

    Goronzy, Jörg J.; Li, Guangjin; Yu, Mingcan; Weyand, Cornelia M.

    2012-01-01

    With increasing age, the ability of the immune system to protect against new antigenic challenges or to control chronic infections erodes. Decline in thymic function and cumulating antigenic experiences of acute and chronic infections threaten T cell homeostasis, but insufficiently explain the failing immune competence and the increased susceptibility for autoimmunity. Alterations in signaling pathways in the aging T cells account for many of the age-related defects. Signaling threshold calibrations seen with aging frequently built on mechanisms that are operational in T cell development and T cell differentiation or are adaptations to the changing environment in the aging host. Age-related changes in transcription of receptors and signaling molecules shift the balance towards inhibitory pathways, most dominantly seen in CD8 T cells and to a lesser degree in CD4 T cells. Prominent examples are the expression of negative regulatory receptors of the CD28 and the TNF receptor superfamilies as well the expression of various cytoplasmic and nuclear dual-specific phosphatases. PMID:22560928

  3. Value Differentiation in Adolescence: The Role of Age and Cultural Complexity

    ERIC Educational Resources Information Center

    Daniel, Ella; Schiefer, David; Mollering, Anna; Benish-Weisman, Maya; Boehnke, Klaus; Knafo, Ariel

    2012-01-01

    Living in complex social worlds, individuals encounter discordant values across life contexts, potentially resulting in different importance of values across contexts. Value differentiation is defined here as the degree to which values receive different importance depending on the context in which they are considered. Early and mid-adolescents (N…

  4. Differentiating the aging of the mitral valve from human and canine myxomatous degeneration

    PubMed Central

    Connell, Patrick S.; Han, Richard I.; Grande-Allen, K. Jane

    2012-01-01

    During the course of both canine and human aging, the mitral valve remodels in generally predictable ways. The connection between these aging changes and the morbidity and mortality that accompany pathologic conditions has not been made clear. By exploring work that has investigated the specific valvular changes in both age and disease, with respect to the cells and the extracellular matrix found within the mitral valve, heretofore unexplored connections between age and myxomatous valve disease can be found. This review addresses several studies that have been conducted to explore such age and disease related changes in extracellular matrix, valvular endothelial and interstitial cells, and valve innervation, and also reviews attempts to correlate aging and myxomatous disease. Such connections can highlight avenues for future research and help provide insight as to when an individual diverts from an aging pattern into a diseased pathway. Recognizing these patterns and opportunities could result in earlier intervention and the hope of reduced morbidity and mortality for patients. PMID:22364720

  5. Loss of proliferation and differentiation capacity of aged human periodontal ligament stem cells and rejuvenation by exposure to the young extrinsic environment.

    PubMed

    Zheng, Wei; Wang, Shi; Ma, Dandan; Tang, Liang; Duan, Yinzhong; Jin, Yan

    2009-09-01

    The application of periodontal ligament stem cells (PDLSCs) may be effective for periodontal regenerative therapy. As tissue regenerative potential may be negatively regulated by aging, whether aging and its microenvironment modify human PDLSCs remains a question. In this study, we compared the proliferation and differentiation capacity of PDLSCs obtained from young and aged donors. Then, we exposed aged PDLSCs to young periodontal ligament cell-conditioned medium (PLC-CM), and young PDLSCs were exposed to aged PLC-CM. Morphological appearance, colony-forming assay, cell cycle analysis, osteogenic and adipogenic induction media, gene expression of cementoblast phenotype, and in vivo differentiation capacities of PDLSCs were evaluated. PDLSCs obtained from aged donors exhibited decreased proliferation and differentiation capacity when compared with those from young donors. Young PLC-CM enhanced the proliferation and differentiation capacity of PDLSCs from aged donors. Aged PDLSCs induced by young PLC-CM showed enhanced tissue-regenerative capacity to produce cementum/periodontal ligament-like structures, whereas young PDLSCs induced by aged PLC-CM transplants mainly formed connective tissues. To our knowledge, this is the first study to mimic the developmental microenvironment of PDLSCs in vitro, and our data suggest that age influences the proliferation and differentiation potential of human PDLSCs, and that the activity of human PDLSCs can be modulated by the extrinsic microenvironment.

  6. Dissociation between Semantic Representations for Motion and Action Verbs: Evidence from Patients with Left Hemisphere Lesions.

    PubMed

    Taylor, Lawrence J; Evans, Carys; Greer, Joanna; Senior, Carl; Coventry, Kenny R; Ietswaart, Magdalena

    2017-01-01

    This multiple single case study contrasted left hemisphere stroke patients (N = 6) to healthy age-matched control participants (N = 15) on their understanding of action (e.g., holding, clenching) and motion verbs (e.g., crumbling, flowing). The tasks required participants to correctly identify the matching verb or associated picture. Dissociations on action and motion verb content depending on lesion site were expected. As predicted for verbs containing an action and/or motion content, modified t-tests confirmed selective deficits in processing motion verbs in patients with lesions involving posterior parietal and lateral occipitotemporal cortex. In contrast, deficits in verbs describing motionless actions were found in patients with more anterior lesions sparing posterior parietal and lateral occipitotemporal cortex. These findings support the hypotheses that semantic representations for action and motion are behaviorally and neuro-anatomically dissociable. The findings clarify the differential and critical role of perceptual and motor regions in processing modality-specific semantic knowledge as opposed to a supportive but not necessary role. We contextualize these results within theories from both cognitive psychology and cognitive neuroscience that make claims over the role of sensory and motor information in semantic representation.

  7. Dissociation between Semantic Representations for Motion and Action Verbs: Evidence from Patients with Left Hemisphere Lesions

    PubMed Central

    Taylor, Lawrence J.; Evans, Carys; Greer, Joanna; Senior, Carl; Coventry, Kenny R.; Ietswaart, Magdalena

    2017-01-01

    This multiple single case study contrasted left hemisphere stroke patients (N = 6) to healthy age-matched control participants (N = 15) on their understanding of action (e.g., holding, clenching) and motion verbs (e.g., crumbling, flowing). The tasks required participants to correctly identify the matching verb or associated picture. Dissociations on action and motion verb content depending on lesion site were expected. As predicted for verbs containing an action and/or motion content, modified t-tests confirmed selective deficits in processing motion verbs in patients with lesions involving posterior parietal and lateral occipitotemporal cortex. In contrast, deficits in verbs describing motionless actions were found in patients with more anterior lesions sparing posterior parietal and lateral occipitotemporal cortex. These findings support the hypotheses that semantic representations for action and motion are behaviorally and neuro-anatomically dissociable. The findings clarify the differential and critical role of perceptual and motor regions in processing modality-specific semantic knowledge as opposed to a supportive but not necessary role. We contextualize these results within theories from both cognitive psychology and cognitive neuroscience that make claims over the role of sensory and motor information in semantic representation. PMID:28261070

  8. Interacting effects of latitude, mass, age, and sex on winter survival of Surf Scoters (Melanitta perspicillata): Implications for differential migration

    USGS Publications Warehouse

    Uher-Koch, Brian D.; Esler, Daniel N.; Iverson, Samuel A.; Ward, David; Boyd, Sean; Kirk, Molly; Lewis, Tyler L.; VanStratt, Corey S.; Brodhead, Katherine M.; Hupp, Jerry; Schmutz, Joel A.

    2016-01-01

    We quantified variation in winter survival of Surf Scoters (Melanitta perspicillata (L., 1758)) across nearly 30° of latitude on the Pacific coast of North America to evaluate potential effects on winter distributions, including observed differential distributions of age and sex classes. We monitored fates of 297 radio-marked Surf Scoters at three study sites: (1) near the northern periphery of their wintering range in southeast Alaska, USA, (2) the range core in British Columbia, Canada, and (3) the southern periphery in Baja California, Mexico. We detected 34 mortalities and determined that survival averaged lower at the range peripheries than in the range core, was lower during mid-winter than during late winter at all sites, and was positively correlated with body mass within locations. Although neither age nor sex class had direct effects, mass effects led to differential survival patterns among classes. When simultaneously incorporating these interacting influences, adult males of mean mass for their location had highest survival at the northern range periphery in Alaska, whereas adult females and juveniles had higher survival at the range core and the southern periphery. Our observations help to explain patterns of differential migration and distribution reported for this species and highlight seasonal periods (mid-winter) and locations (range peripheries) of elevated levels of mortality for demographically important age–sex classes (adult females).

  9. Brain aging and memory: new findings help differentiate forgetfulness and dementia.

    PubMed

    D'Esposito, M; Weksler, M E

    2000-06-01

    Geriatrics is pleased to highlight the clinical implications of research topics supported by the American Federation for Aging Research (AFAR). AFAR is a leading private organization supporting research on the aging process and diseases of older populations. More than 900 physicians, scientists, and students have received AFAR grants totaling more than $20 million since AFAR was founded by Irving S. Wright, MD, in 1981. The articles in the New Frontiers series are designed to provide primary care physicians with insight into the pathogenesis, diagnosis, prevention, and treatment of the diseases of aging.

  10. Personal semantics: Is it distinct from episodic and semantic memory? An electrophysiological study of memory for autobiographical facts and repeated events in honor of Shlomo Bentin.

    PubMed

    Renoult, Louis; Tanguay, Annick; Beaudry, Myriam; Tavakoli, Paniz; Rabipour, Sheida; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian; Davidson, Patrick S R

    2016-03-01

    Declarative memory is thought to consist of two independent systems: episodic and semantic. Episodic memory represents personal and contextually unique events, while semantic memory represents culturally-shared, acontextual factual knowledge. Personal semantics refers to aspects of declarative memory that appear to fall somewhere in between the extremes of episodic and semantic. Examples include autobiographical knowledge and memories of repeated personal events. These two aspects of personal semantics have been studied little and rarely compared to both semantic and episodic memory. We recorded the event-related potentials (ERPs) of 27 healthy participants while they verified the veracity of sentences probing four types of questions: general (i.e., semantic) facts, autobiographical facts, repeated events, and unique (i.e., episodic) events. Behavioral results showed equivalent reaction times in all 4 conditions. True sentences were verified faster than false sentences, except for unique events for which no significant difference was observed. Electrophysiological results showed that the N400 (which is classically associated with retrieval from semantic memory) was maximal for general facts and the LPC (which is classically associated with retrieval from episodic memory) was maximal for unique events. For both ERP components, the two personal semantic conditions (i.e., autobiographical facts and repeated events) systematically differed from semantic memory. In addition, N400 amplitudes also differentiated autobiographical facts from unique events. Autobiographical facts and repeated events did not differ significantly from each other but their corresponding scalp distributions differed from those associated with general facts. Our results suggest that the neural correlates of personal semantics can be distinguished from those of semantic and episodic memory, and may provide clues as to how unique events are transformed to semantic memory.

  11. 29 CFR 1625.7 - Differentiations based on reasonable factors other than age.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... exist must be decided on the basis of all the particular facts and circumstances surrounding each... the grounds that it is a “factor other than” age, and such a practice has an adverse impact...

  12. 29 CFR 1625.7 - Differentiations based on reasonable factors other than age.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... other than age must be decided on the basis of all the particular facts and circumstances surrounding... assessed the adverse impact of its employment practice on older workers; and (v) The degree of the harm...

  13. 29 CFR 1625.7 - Differentiations based on reasonable factors other than age.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... other than age must be decided on the basis of all the particular facts and circumstances surrounding... assessed the adverse impact of its employment practice on older workers; and (v) The degree of the harm...

  14. Transfection of the IHH gene into rabbit BMSCs in a simulated microgravity environment promotes chondrogenic differentiation and inhibits cartilage aging

    PubMed Central

    Liu, Peng-Cheng; Liu, Kuan; Liu, Jun-Feng; Xia, Kuo; Chen, Li-Yang; Wu, Xing

    2016-01-01

    The effect of overexpressing the Indian hedgehog (IHH) gene on the chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMSCs) was investigated in a simulated microgravity environment. An adenovirus plasmid encoding the rabbit IHH gene was constructed in vitro and transfected into rabbit BMSCs. Two large groups were used: conventional cell culture and induction model group and simulated microgravity environment group. Each large group was further divided into blank control group, GFP transfection group, and IHH transfection group. During differentiation induction, the expression levels of cartilage-related and cartilage hypertrophy-related genes and proteins in each group were determined. In the conventional model, the IHH transfection group expressed high levels of cartilage-related factors (Coll2 and ANCN) at the early stage of differentiation induction and expressed high levels of cartilage hypertrophy-related factors (Coll10, annexin 5, and ALP) at the late stage. Under the simulated microgravity environment, the IHH transfection group expressed high levels of cartilage-related factors and low levels of cartilage hypertrophy-related factors at all stages of differentiation induction. Under the simulated microgravity environment, transfection of the IHH gene into BMSCs effectively promoted the generation of cartilage and inhibited cartilage aging and osteogenesis. Therefore, this technique is suitable for cartilage tissue engineering. PMID:27802423

  15. Differential regulation of hepatic apoptotic pathways by dietary olive and sunflower oils in the aging rat.

    PubMed

    Bello, Rosario I; Gómez-Díaz, Consuelo; Burón, María I; Navas, Plácido; Villalba, José M

    2006-11-01

    In this work we have studied how dietary fat affects aging-related changes in a number of factors that regulate rat hepatic apoptosis. Animals were fed lifelong with two experimental diets containing either virgin olive oil or sunflower oil as dietary fat. Caspases of the intrinsic and extrinsic pathways of apoptosis, Bcl-2 and Bax polypeptide levels, and plasma membrane neutral sphingomyelinase activity were determined at 6, 12, and 24 months of age. Caspase-8/10 activity (a marker of the extrinsic pathway) was not affected by either aging or dietary fat, but activities of both caspase-9 (a marker of the intrinsic pathway) and caspase-3 (an executioner caspase) were significantly depressed in liver from animals fed on a sunflower oil-based diet. These decreases were not observed in animals fed with a diet based on virgin olive oil, which also resulted in significantly lower Bcl-2/Bax ratios. On the other hand, in comparison with sunflower, dietary olive oil decreased oxidative stress in liver from aged rats, resulting in lower levels of membrane hydroperoxides and higher coenzyme Q levels in plasma membrane. Plasma membrane Mg(2+)-dependent neutral sphingomyelinase was strongly activated in aged rats fed on the sunflower oil diet, but no aging-related increase was observed in animals fed on the olive oil diet. Our results support that dietary oil can alter significantly the susceptibility of hepatocytes to different apoptotic stimuli by altering both pro- and anti-apoptotic mediators, which reinforces the importance of the diet in aging studies. Because virgin olive oil may increase susceptibility of hepatocytes to apoptosis induced through the intrinsic pathway under conditions of decreased oxidative stress, our results may have important implications to understand the potential beneficial effects of that edible oil against liver carcinogenesis during aging.

  16. Differentiated effects of social participation components on suicidal ideation across age groups in South Korea

    PubMed Central

    2013-01-01

    Background Suicide among adults in the Korean population merits study to improve the understanding of the salient risk and protective factors because suicide rates in Korea have increased dramatically over the past 20 years. However, the association between social participation and suicidal ideation is poorly understood. Thus, this study aimed to identify the components of social participation in Korean society and to examine the processes through which the components of social participation influence the degree of suicidal ideation people experience across age groups. Methods This study used survey data from the 2010 Seoul Welfare Panel Study. The sample population was restricted to adults aged 20 or older and was categorised into three groups by respondents’ ages. The groups were defined as 'young adults’ (aged 20–39), 'middle-aged adults’ (aged 40–64) and 'the elderly’ (age 65 or more). Three dimensions of social participation were identified by factor analysis – friendship network and hobby group, religious involvement, and instrumental social participation. Results In the young adult group, only instrumental participation was statistically significant (-0.10, p = 0.06). In the middle-aged adult group, only friendship network and hobby group had a strong association with suicidal ideation (-0.11, p = 0.01). Interestingly, for the elderly, religious involvement was related to suicidal ideation, but in a positive way (0.26, p = 0.02). Conclusion The study results supported the theory that different components of social participation are associated with a lower risk of suicidal ideation in different stages of adulthood. PMID:24067075

  17. The representation of conceptual knowledge: visual, auditory, and olfactory imagery compared with semantic processing.

    PubMed

    Palmiero, Massimiliano; Di Matteo, Rosalia; Belardinelli, Marta Olivetti

    2014-05-01

    Two experiments comparing imaginative processing in different modalities and semantic processing were carried out to investigate the issue of whether conceptual knowledge can be represented in different format. Participants were asked to judge the similarity between visual images, auditory images, and olfactory images in the imaginative block, if two items belonged to the same category in the semantic block. Items were verbally cued in both experiments. The degree of similarity between the imaginative and semantic items was changed across experiments. Experiment 1 showed that the semantic processing was faster than the visual and the auditory imaginative processing, whereas no differentiation was possible between the semantic processing and the olfactory imaginative processing. Experiment 2 revealed that only the visual imaginative processing could be differentiated from the semantic processing in terms of accuracy. These results showed that the visual and auditory imaginative processing can be differentiated from the semantic processing, although both visual and auditory images strongly rely on semantic representations. On the contrary, no differentiation is possible within the olfactory domain. Results are discussed in the frame of the imagery debate.

  18. An Investigation into Semantic and Phonological Processing in Individuals with Williams Syndrome

    ERIC Educational Resources Information Center

    Lee, Cheryl S.; Binder, Katherine S.

    2014-01-01

    Purpose: The current study examined semantic and phonological processing in individuals with Williams syndrome (WS). Previous research in language processing in individuals with WS suggests a complex linguistic system characterized by "deviant" semantic organization and differential phonological processing. Method: Two experiments…

  19. Musicians' Enhanced Neural Differentiation of Speech Sounds Arises Early in Life: Developmental Evidence from Ages 3 to 30

    PubMed Central

    Strait, Dana L.; O'Connell, Samantha; Parbery-Clark, Alexandra; Kraus, Nina

    2014-01-01

    The perception and neural representation of acoustically similar speech sounds underlie language development. Music training hones the perception of minute acoustic differences that distinguish sounds; this training may generalize to speech processing given that adult musicians have enhanced neural differentiation of similar speech syllables compared with nonmusicians. Here, we asked whether this neural advantage in musicians is present early in life by assessing musically trained and untrained children as young as age 3. We assessed auditory brainstem responses to the speech syllables /ba/ and /ga/ as well as auditory and visual cognitive abilities in musicians and nonmusicians across 3 developmental time-points: preschoolers, school-aged children, and adults. Cross-phase analyses objectively measured the degree to which subcortical responses differed to these speech syllables in musicians and nonmusicians for each age group. Results reveal that musicians exhibit enhanced neural differentiation of stop consonants early in life and with as little as a few years of training. Furthermore, the extent of subcortical stop consonant distinction correlates with auditory-specific cognitive abilities (i.e., auditory working memory and attention). Results are interpreted according to a corticofugal framework for auditory learning in which subcortical processing enhancements are engendered by strengthened cognitive control over auditory function in musicians. PMID:23599166

  20. Semantic and gender priming in frontotemporal dementia.

    PubMed

    Repetto, Claudia; Manenti, Rosa; Cappa, Stefano; Miniussi, Carlo; Riva, Giuseppe

    2009-01-01

    Modifications of language processing can be observed both in normal aging and in the most common forms of degenerative dementia, such as Alzheimer's disease and the spectrum of frontotemporal dementias. The present experiment tests at the same time semantic and syntactic aspects of language processing in patients with frontotemporal dementia, using an online paradigm that allows researchers to evaluate the real linguistic competence of the patients.

  1. Mechanosensory Neuron Aging: Differential Trajectories with Lifespan-Extending Alaskan Berry and Fungal Treatments in Caenorhabditis elegans

    PubMed Central

    Scerbak, Courtney; Vayndorf, Elena M.; Hernandez, Alicia; McGill, Colin; Taylor, Barbara E.

    2016-01-01

    Many nutritional interventions that increase lifespan are also proposed to postpone age-related declines in motor and cognitive function. Potential sources of anti-aging compounds are the plants and fungi that have adapted to extreme environments. We studied the effects of four commonly consumed and culturally relevant Interior Alaska berry and fungus species (bog blueberry, lowbush cranberry, crowberry, and chaga) on the decline in overall health and neuron function and changes in touch receptor neuron morphology associated with aging. We observed increased wild-type Caenorhabditis elegans lifespan and improved markers of healthspan upon treatment with Alaskan blueberry, lowbush cranberry, and chaga extracts. Interestingly, although all three treatments increased lifespan, they differentially affected the development of aberrant morphologies in touch receptor neurons. Blueberry treatments decreased anterior mechanosensory neuron (ALM) aberrations (i.e., extended outgrowths and abnormal cell bodies) while lowbush cranberry treatment increased posterior mechanosensory neuron (PLM) aberrations, namely process branching. Chaga treatment both decreased ALM aberrations (i.e., extended outgrowths) and increased PLM aberrations (i.e., process branching and loops). These results support the large body of knowledge positing that there are multiple cellular strategies and mechanisms for promoting health with age. Importantly, these results also demonstrate that although an accumulation of abnormal neuron morphologies is associated with aging and decreased health, not all of these morphologies are detrimental to neuronal and organismal health. PMID:27486399

  2. Transformation relaxation and aging in a CuZnAl shape-memory alloy studied by modulated differential scanning calorimetry

    SciTech Connect

    Wei, Z.G.

    1998-11-01

    The reverse martensitic transformation and aging processes in a polycrystalline Cu-23.52 at. pct Zn-9.65 at. pct Al shape-memory alloy have been studied using the recently developed modulated differential scanning calorimetry (MDSC) technique, and some new findings are obtained. By separating the nonreversing heat flow from the reversing heat flow, MDSC can better characterize the thermodynamic, kinetic, and hysteretic feature of thermoelastic martensitic transformations. Two kinds of exothermal relaxation peaks have been identified and separated from the endothermal reverse martensitic transformations: one is associated with the movement of twin interfaces or martensite-parent interfaces, and another is due to the atomic reordering in the parent phase via a vacancy mechanism. The martensite aging processes have been examined, and two stages of the aging process has been distinguished: the first stage of aging is characterized by the stabilization of martensite, as manifested in the increase in the reversing enthalpy of the reverse martensitic transformation and in the transformation temperatures, and the second stage, is in fact, the decomposition of the martensite on prolonged aging, accompanied by a decrease in the transformation enthalpy. The results suggest that the mechanisms of the relaxation in the martensite and in the parent phase may be quite different.

  3. Phospho1 deficiency transiently modifies bone architecture yet produces consistent modification in osteocyte differentiation and vascular porosity with ageing

    PubMed Central

    Javaheri, B.; Carriero, A.; Staines, K.A.; Chang, Y.-M.; Houston, D.A.; Oldknow, K.J.; Millan, J.L.; Kazeruni, Bassir N.; Salmon, P.; Shefelbine, S.; Farquharson, C.; Pitsillides, A.A.

    2015-01-01

    PHOSPHO1 is one of principal proteins involved in initiating bone matrix mineralisation. Recent studies have found that Phospho1 KO mice (Phospho1-R74X) display multiple skeletal abnormalities with spontaneous fractures, bowed long bones, osteomalacia and scoliosis. These analyses have however been limited to young mice and it remains unclear whether the role of PHOSPHO1 is conserved in the mature murine skeleton where bone turnover is limited. In this study, we have used ex-vivo computerised tomography to examine the effect of Phospho1 deletion on tibial bone architecture in mice at a range of ages (5, 7, 16 and 34 weeks of age) to establish whether its role is conserved during skeletal growth and maturation. Matrix mineralisation has also been reported to influence terminal osteoblast differentiation into osteocytes and we have also explored whether hypomineralised bones in Phospho1 KO mice exhibit modified osteocyte lacunar and vascular porosity. Our data reveal that Phospho1 deficiency generates age-related defects in trabecular architecture and compromised cortical microarchitecture with greater porosity accompanied by marked alterations in osteocyte shape, significant increases in osteocytic lacuna and vessel number. Our in vitro studies examining the behaviour of osteoblast derived from Phospho1 KO and wild-type mice reveal reduced levels of matrix mineralisation and modified osteocytogenic programming in cells deficient in PHOSPHO1. Together our data suggest that deficiency in PHOSPHO1 exerts modifications in bone architecture that are transient and depend upon age, yet produces consistent modification in lacunar and vascular porosity. It is possible that the inhibitory role of PHOSPHO1 on osteocyte differentiation leads to these age-related changes in bone architecture. It is also intriguing to note that this apparent acceleration in osteocyte differentiation evident in the hypomineralised bones of Phospho1 KO mice suggests an uncoupling of the interplay

  4. Semantic knowledge fractionations: verbal propositions vs. perceptual input? Evidence from a child with Klinefelter syndrome.

    PubMed

    Robinson, Sally J; Temple, Christine M

    2013-04-01

    This paper addresses the relative independence of different types of lexical- and factually-based semantic knowledge in JM, a 9-year-old boy with Klinefelter syndrome (KS). JM was matched to typically developing (TD) controls on the basis of chronological age. Lexical-semantic knowledge was investigated for common noun (CN) and mathematical vocabulary items (MV). Factually-based semantic knowledge was investigated for general and number facts. For CN items, JM's lexical stores were of a normal size but the volume of correct 'sensory feature' semantic knowledge he generated within verbal item descriptions was significantly reduced. He was also significantly impaired at naming item descriptions and pictures, particularly for fruit and vegetables. There was also weak object decision for fruit and vegetables. In contrast, for MV items, JM's lexical stores were elevated, with no significant difference in the amount and type of correct semantic knowledge generated within verbal item descriptions and normal naming. JM's fact retrieval accuracy was normal for all types of factual knowledge. JM's performance indicated a dissociation between the representation of CN and MV vocabulary items during development. JM's preserved semantic knowledge of facts in the face of impaired semantic knowledge of vocabulary also suggests that factually-based semantic knowledge representation is not dependent on normal lexical-semantic knowledge during development. These findings are discussed in relation to the emergence of distinct semantic knowledge representations during development, due to differing degrees of dependency upon the acquisition and representation of semantic knowledge from verbal propositions and perceptual input.

  5. The Abilities and Differential Difficulties of Children with Autism Spectrum Disorder and Children with Specific Language Impairment to Use Semantic and Social Contexts to Infer and Recall Novel Words

    ERIC Educational Resources Information Center

    Goldman, Melody R.

    2010-01-01

    Two studies assessed the ability of 12 pre-school children with Autism Spectrum Disorder (ASD; N = 7) or Specific Language Impairment (SLI; N = 5) to use semantic context and eye gaze to infer the meanings of novel nouns, and to recall those meanings after a 24-hour delay. In Experiment 1, the children heard statements containing a familiar,…

  6. Differential effects of aging on transport properties of anterior and posterior human sclera.

    PubMed

    Boubriak, O A; Urban, J P G; Bron, A J

    2003-06-01

    The transport properties and composition of 44 pairs of human sclera, 37-91 years were compared. Solute transport, diffusion and partition coefficients of posterior sclera for solutes ranging in mass from 0.023-70kDa were higher than those of anterior sclera; the posterior region was also more hydrated. The differences in partition coefficient between anterior and posterior sclera became more pronounced as solute molecular weight increased. Partition coefficients and hydration of both regions decreased with increasing age. Chondroitinase ABC digestion, which removed the majority of glycosaminoglycans, increased partition coefficients of both regions significantly. These results suggest that for regions of equal scleral thickness, neglecting the influence of vascular factors, drug delivery will be more readily achieved across the posterior sclera than the anterior sclera in the age group studied and that, for both regions, ease of delivery will decrease with decreasing age.

  7. Differential effect of aging on axon sprouting and regenerative growth in spinal cord injury.

    PubMed

    Jaerve, Anne; Schiwy, Nora; Schmitz, Christine; Mueller, Hans W

    2011-10-01

    The demographics of acute spinal cord injury (SCI) are changing with an increased incidence in older age. However, the influence of aging on the regenerative growth potential of central nervous system (CNS) axons following SCI is not known. We investigated axonal sprouting along with the efficiency of the infusion of the stromal cell-derived growth factor-1 (SDF-1/CXCL12) and regenerative growth along with the anti-scarring treatment (AST) in young (2-3 months) and geriatric (22-28 months) female rats following SCI. AST included local injection of iron chelator (2,2'-dipyridine-5,5'-dicarboxylic acid) and 8-bromo-cyclic adenosine monophosphate solution into the lesion core. Axon outgrowth was investigated by immunohistological methods at 5 weeks after a partial dorsal hemisection at thoracic level T8. We found that aging significantly reduces spontaneous axon sprouting of corticospinal (CST), serotonergic (5-HT) raphespinal and catecholaminergic (TH) coerulospinal tracts in distinct regions of the spinal cord rostral to the lesion. However, impairment of axon sprouting could be markedly attenuated in geriatric animals by local infusion of SDF-1. Unexpectedly and in contrast to rostral sprouting, aging does not diminish the regenerative growth capacity of 5-HT-, TH- and calcitonin gene-related peptide (CGRP)-immunoreactive axons at 5 weeks after SCI. Moreover, 5-HT and TH axons maintain the ability to react upon AST with significantly enhanced regeneration in aged animals. These data are the first to demonstrate, that old age compromises axonal plasticity, but not regenerative growth, after SCI in a fiber tract-specific manner. Furthermore, AST and SDF-1 infusions remain efficient, which implicates that therapy in elderly patients is still feasible.

  8. Age-dependent differential expression profile of a novel intergenic long noncoding RNA in rat brain.

    PubMed

    Kour, Sukhleen; Rath, Pramod C

    2015-11-01

    Long noncoding RNAs (lncRNAs) are ≥200 nt long, abundant class of non-protein coding RNAs that are transcribed in complex, sense- and antisense patterns from the intergenic and intronic regions of mammalian genome. Mammalian central nervous system constitutes the largest repertoire of noncoding transcripts that are known to be expressed in developmentally regulated and cell-type specific manners. Although many lncRNAs, functioning in the brain development and diseases are known, none involved in brain aging has been reported so far. Here, we report involvement of a novel, repeat sequence (simple repeats and SINES)-containing, trans-spliced, long intergenic non-protein coding RNA (lincRNA), named as LINC-RBE (rat brain expressed transcript) involved in maturation and aging of mammalian brain. The LINC-RBE is strongly expressed in the rat brain and the upstream/downstream sequences of its DNA in the chromosome 5 contain binding sites for many cell growth, survival and development-specific transcriptional factors. Through RT-PCR and RNA in situ hybridization, LINC-RBE was found to be expressed in an age-dependent manner with significantly higher level of expression in the brain of adult (16 weeks) compared to both immature (4 weeks) and old (70 weeks) rats. Moreover, the expression pattern of the LINC-RBE showed distinct association with the specific neuro-anatomical regions, cell types and sub-cellular compartments of the rat brain in an age-related manner. Thus, its expression increased from immature stage to adulthood and declined further in old age. This is a first-time report of involvement of an intergenic repeat sequence-containing lncRNA in different regions of the rat brain in an age-dependent manner.

  9. Age-dependent differential expression profile of a novel intergenic long noncoding RNA in rat brain.

    PubMed

    Kour, Sukhleen; Rath, Pramod C

    2015-12-01

    Long noncoding RNAs (lncRNAs) are ≥ 200 nt long, abundant class of non-protein coding RNAs that are transcribed in complex, sense- and antisense patterns from the intergenic and intronic regions of mammalian genome. Mammalian central nervous system constitutes the largest repertoire of noncoding transcripts that are known to be expressed in developmentally regulated and cell-type specific manners. Although many lncRNAs, functioning in the brain development and diseases are known, none involved in brain aging has been reported so far. Here, we report involvement of a novel, repeat sequence (simple repeats and SINES)-containing, trans-spliced, long intergenic non-protein coding RNA (lincRNA), named as LINC-RBE (rat brain expressed transcript) involved in maturation and aging of mammalian brain. The LINC-RBE is strongly expressed in the rat brain and the upstream/downstream sequences of its DNA in the chromosome 5 contain binding sites for many cell growth, survival and development-specific transcriptional factors. Through RT-PCR and RNA in situ hybridization, LINC-RBE was found to be expressed in an age-dependent manner with significantly higher level of expression in the brain of adult (16 week) compared to both immature (4 week) and old (70 week) rats. Moreover, the expression pattern of the LINC-RBE showed distinct association with the specific neuro-anatomical regions, cell types and sub-cellular compartments of the rat brain in an age-related manner. Thus, its expression increased from immature stage to adulthood and declined further in old age. This is a first-time report of involvement of an intergenic repeat sequence-containing lncRNA in different regions of the rat brain in an age-dependent manner.

  10. From Data to Semantic Information

    NASA Astrophysics Data System (ADS)

    Floridi, Luciano

    2003-06-01

    There is no consensus yet on the definition of semantic information. This paper contributes to the current debate by criticising and revising the Standard Definition of semantic Information (SDI) as meaningful data, in favour of the Dretske-Grice approach: meaningful and well-formed data constitute semantic information only if they also qualify as contingently truthful. After a brief introduction, SDI is criticised for providing necessary but insufficient conditions for the definition of semantic information. SDI is incorrect because truth-values do not supervene on semantic information, and misinformation (that is, false semantic information) is not a type of semantic information, but pseudo-information, that is not semantic information at all. This is shown by arguing that none of the reasons for interpreting misinformation as a type of semantic information is convincing, whilst there are compelling reasons to treat it as pseudo-information. As a consequence, SDI is revised to include a necessary truth-condition. The last section summarises the main results of the paper and indicates the important implications of the revised definition for the analysis of the deflationary theories of truth, the standard definition of knowledge and the classic, quantitative theory of semantic information.

  11. Latent Semantic Indexing of medical diagnoses using UMLS semantic structures.

    PubMed Central

    Chute, C. G.; Yang, Y.; Evans, D. A.

    1991-01-01

    The relational files within the UMLS Metathesaurus contain rich semantic associations to main concepts. We invoked the technique of Latent Semantic Indexing to generate information matrices based on these relationships and created "semantic vectors" using singular value decomposition. Evaluations were made on the complete set and subsets of Metathesaurus main concepts with the semantic type "Disease or Syndrome." Real number matrices were created with main concepts, lexical variants, synonyms, and associated expressions. Ancestors, children, siblings, and related terms were added to alternative matrices, preserving the hierarchical direction of the relation as the imaginary component of a complex number. Preliminary evaluation suggests that this technique is robust. A major advantage is the exploitation of semantic features which derive from a statistical decomposition of UMLS structures, possibly reducing dependence on the tedious construction of semantic frames by humans. PMID:1807584

  12. General equation for the differential pathlength factor of the frontal human head depending on wavelength and age.

    PubMed

    Scholkmann, Felix; Wolf, Martin

    2013-10-01

    Continuous-wave near-infrared spectroscopy and near-infrared imaging enable the measurement of relative concentration changes in oxy- and deoxyhemoglobin and thus hemodynamics and oxygenation. The accuracy of determined changes depends mainly on the modeling of the light transport through the probed tissue. Due to the highly scattering nature of tissue, the light path is longer than the source-detector separation (d). This is incorporated in modeling by multiplying d by a differential pathlength factor (DPF) which depends on several factors such as wavelength, age of the subject, and type of tissue. In the present work, we derive a general DPF equation for the frontal human head, incorporating dependency on wavelength and age, based on published data. We validated the equation using different data sets of experimentally determined DPFs from six independent studies.

  13. Auditory Middle Latency Responses in Chronic Smokers Compared to Nonsmokers: Differential Effects of Stimulus and Age

    ERIC Educational Resources Information Center

    Ramkissoon, Ishara; Beverly, Brenda L.

    2014-01-01

    Purpose: Effects of clicks and tonebursts on early and late auditory middle latency response (AMLR) components were evaluated in young and older cigarette smokers and nonsmokers. Method: Participants ( n = 49) were categorized by smoking and age into 4 groups: (a) older smokers, (b) older nonsmokers, (c) young smokers, and (d) young nonsmokers.…

  14. [Differentiation of radial glia cells into astrocytes is a possible ageing mechanism in mammals].

    PubMed

    Boĭko, A G

    2007-01-01

    Several obscure facts of gerontology are briefly reviewed. A attempt is made to shape new notions of the phenomenon based on the astrocyte hypothesis of ageing in mammals. This hypothesis interprets mammal ageing as a genetic disease with fatal outcome. The disease is caused by single character acquired by the theromorph lineage of the vertebrates in the course of evolution: the transformation of radial glia cells (RGC) into star-shaped astrocytes during the postnatal development, i.e. the disappearance of the fetal radial ways of nerve cell migration from proliferative zones to the sites of their ultimate localization in the brain of adult individuals. This process is the cause for the mammal brain being postmitotic. The disappearance of RGC induces a cascade of system processes termed age-dependent mechanism of self-destruction of mammals (AMSM). The disappearance of RGC inhibits the replacement of the nerve cells that have exhausted their living resources. Nerve cells are rigidly specialized and have restricted lifetime and ability of reparation. After some period, the level of homeostasis in nerve cells starts changing steadily for the worse due to irreversible pathological changes in the cells (especially in the neurosecretory cells). This brings damage to life-sypport systems of the mammal organism thus causing its death. The species-specific maximum life span is thus determined by the rate of metabolism in the organism. AMSM probably displays a general evolutionary principle: outer factors causing death (in non-ageing organisms) are replaced by inner factors.

  15. Differential Profiles of Risk of Self-Harm among Clinically Referred Primary School Aged Children

    ERIC Educational Resources Information Center

    Angelkovska, Anne; Houghton, Stephen; Hopkins, Sarah

    2012-01-01

    Risk of self-harm among clinic referred children aged 6- to 12-years-old was investigated using the recently developed Self-Harm Risk Assessment for Children (SHRAC) instrument which comprises six factors: Affect traits; verbalizing of self-harm; socialization; dissociation; self-directing; and self-appraisal. The SHRAC was completed by the…

  16. Differential Effects of Intelligence, Perceptual Speed and Age on Growth in Attentional Speed and Accuracy

    ERIC Educational Resources Information Center

    Goldhammer, Frank; Rauch, Wolfgang A.; Schweizer, Karl; Moosbrugger, Helfried

    2010-01-01

    The study investigates the effects of intelligence, perceptual speed and age on intraindividual growth in attentional speed and attentional accuracy over the course of a 6-minute testing session. A sample of 193 subjects completed the Advanced Progressive Matrices and the Vienna Matrices Test representing intelligence, the tests Alertness and…

  17. Specific protein changes contribute to the differential muscle mass loss during ageing.

    PubMed

    Capitanio, Daniele; Vasso, Michele; De Palma, Sara; Fania, Chiara; Torretta, Enrica; Cammarata, Francesco P; Magnaghi, Valerio; Procacci, Patrizia; Gelfi, Cecilia

    2016-02-01

    In the skeletal muscle, the ageing process is characterized by a loss of muscle mass and strength, coupled with a decline of mitochondrial function and a decrease of satellite cells. This profile is more pronounced in hindlimb than in forelimb muscles, both in humans and in rodents. Utilizing light and electron microscopy, myosin heavy chain isoform distribution, proteomic analysis by 2D-DIGE, MALDI-TOF MS and quantitative immunoblotting, this study analyzes the protein levels and the nuclear localization of specific molecules, which can contribute to a preferential muscle loss. Our results identify the molecular changes in the hindlimb (gastrocnemius) and forelimb (triceps) muscles during ageing in rats (3- and 22-month-old). Specifically, the oxidative metabolism contributes to tissue homeostasis in triceps, whereas respiratory chain disruption and oxidative-stress-induced damage imbalance the homeostasis in gastrocnemius muscle. High levels of dihydrolipoyllysine-residue acetyltransferase (Dlat) and ATP synthase subunit alpha (Atp5a1) are detected in triceps and gastrocnemius, respectively. Interestingly, in triceps, both molecules are increased in the nucleus in aged rats and are associated to an increased protein acetylation and myoglobin availability. Furthermore, autophagy is retained in triceps whereas an enhanced fusion, decrement of mitophagy and of regenerative potential is observed in aged gastrocnemius muscle.

  18. Grammatical Differentiation between Speech and Writing in Children Aged 8 to 12.

    ERIC Educational Resources Information Center

    Perera, Katharine

    Data from a language development project at the Polytechnic of Wales were used to compare the speech and writing of 48 monolingual English-speaking children. The 48 children came from three groups, aged 8, 10, and 12. For the collection of spoken data, the children, divided into groups of three, were tape recorded while they made a construction…

  19. Differential effects of aging on spatial learning through exploratory navigation and map reading

    PubMed Central

    Yamamoto, Naohide; DeGirolamo, Gregory J.

    2012-01-01

    It has been shown that abilities in spatial learning and memory are adversely affected by aging. The present study was conducted to investigate whether increasing age has equal consequences for all types of spatial learning or impacts certain types of spatial learning selectively. Specifically, two major types of spatial learning, exploratory navigation and map reading, were contrasted. By combining a neuroimaging finding that the medial temporal lobe (MTL) is especially important for exploratory navigation and a neurological finding that the MTL is susceptible to age-related atrophy, it was hypothesized that spatial learning through exploratory navigation would exhibit a greater decline in later life than spatial learning through map reading. In an experiment, young and senior participants learned locations of landmarks in virtual environments either by navigating in them in the first-person perspective or by seeing aerial views of the environments. Results showed that senior participants acquired less accurate memories of the layouts of landmarks than young participants when they navigated in the environments, but the two groups did not differ in spatial learning performance when they viewed the environments from the aerial perspective. These results suggest that spatial learning through exploratory navigation is particularly vulnerable to adverse effects of aging, whereas elderly adults may be able to maintain their map reading skills relatively well. PMID:22701423

  20. Granulomatous orchitis in a pre-pubertal school-aged child: differential diagnosis dilemmas.

    PubMed

    Jesus, Lisieux E; Rocha, Kátia L M; Caldas, Maria L R; Fonseca, Elissa

    2012-10-01

    A 6-year-old male presented with testicular growth and persistent chronic orchiepididymitis with high inflammatory markers (C reactive protein and erythrocyte sedimentation rate). Biopsies of the testes and epididymides showed bilateral epididymal and testicular granulomata, testicular fibrosis and chronic inflammatory infiltration, and the histological diagnosis was granulomatous orchitis. The symptoms receded with oral corticosteroids. Although rare, granulomatous orchitis is a possible diagnosis in children presenting testicular enlargement. It is important to differentiate it from testicular tumors (if necessary with testicular biopsy) and to investigate its association with systemic vasculitis and infectious diseases.

  1. Aging- and injury-related differential apoptotic response in the dentate gyrus of the hippocampus in rats following brain trauma

    PubMed Central

    Sun, Dong; McGinn, Melissa; Hankins, Jeanette E.; Mays, Katherine M.; Rolfe, Andrew; Colello, Raymond J.

    2013-01-01

    revealed both age-associated and injury-induced changes in the expression levels of three apoptotic-related proteins: hippocalcin, leucine-rich acidic nuclear protein and heat shock protein 27. Taken together, this study revealed distinct apoptotic responses following TBI in the juvenile and aged brain which may contribute to the differential cognitive recovery observed. PMID:24385964

  2. Complex Semantic Networks

    NASA Astrophysics Data System (ADS)

    Teixeira, G. M.; Aguiar, M. S. F.; Carvalho, C. F.; Dantas, D. R.; Cunha, M. V.; Morais, J. H. M.; Pereira, H. B. B.; Miranda, J. G. V.

    Verbal language is a dynamic mental process. Ideas emerge by means of the selection of words from subjective and individual characteristics throughout the oral discourse. The goal of this work is to characterize the complex network of word associations that emerge from an oral discourse from a discourse topic. Because of that, concepts of associative incidence and fidelity have been elaborated and represented the probability of occurrence of pairs of words in the same sentence in the whole oral discourse. Semantic network of words associations were constructed, where the words are represented as nodes and the edges are created when the incidence-fidelity index between pairs of words exceeds a numerical limit (0.001). Twelve oral discourses were studied. The networks generated from these oral discourses present a typical behavior of complex networks and their indices were calculated and their topologies characterized. The indices of these networks obtained from each incidence-fidelity limit exhibit a critical value in which the semantic network has maximum conceptual information and minimum residual associations. Semantic networks generated by this incidence-fidelity limit depict a pattern of hierarchical classes that represent the different contexts used in the oral discourse.

  3. Growth differentiation factor 6 derived from mesenchymal stem/stromal cells reduces age-related functional deterioration in multiple tissues

    PubMed Central

    Hisamatsu, Daisuke; Ohno-Oishi, Michiko; Nakamura, Shiho; Mabuchi, Yo; Naka-Kaneda, Hayato

    2016-01-01

    The senescence-associated secretory phenotype (SASP) has attracted attention as a mechanism that connects cellular senescence to tissue dysfunction, and specific SASP factors have been identified as systemic pro-aging factors. However, little is known about the age-dependent changes in the secretory properties of stem cells. Young, but not old, mesenchymal stem/stromal cells (MSCs) are a well-known source of critical regenerative factors, but the identity of these factors remains elusive. In this study, we identified growth differentiation factor 6 (Gdf6; also known as Bmp13 and CDMP-2) as a regenerative factor secreted from young MSCs. The expression of specific secretory factors, including Gdf6, was regulated by the microRNA (miRNA) miR-17, whose expression declined with age. Upregulation of Gdf6 restored the osteogenic capacity of old MSCs in vitro and exerted positive effects in vivo on aging-associated pathologies such as reduced lymphopoiesis, insufficient muscle repair, reduced numbers of neural progenitors in the brain, and chronic inflammation. Our results suggest that manipulation of miRNA could enable control of the SASP, and that regenerative factors derived from certain types of young cells could be used to treat geriatric diseases. PMID:27311402

  4. Self-reported physical activity and objective aerobic fitness: differential associations with gray matter density in healthy aging

    PubMed Central

    Zlatar, Zvinka Z.; McGregor, Keith M.; Towler, Stephen; Nocera, Joe R.; Dzierzewski, Joseph M.; Crosson, Bruce

    2015-01-01

    Aerobic fitness (AF) and self-reported physical activity (srPA) do not represent the same construct. However, many exercise and brain aging studies interchangeably use AF and srPA measures, which may be problematic with regards to how these metrics are associated with brain outcomes, such as morphology. If AF and PA measures captured the same phenomena, regional brain volumes associated with these measures should directly overlap. This study employed the general linear model to examine the differential association between objectively-measured AF (treadmill assessment) and srPA (questionnaire) with gray matter density (GMd) in 29 cognitively unimpaired community-dwelling older adults using voxel based morphometry. The results show significant regional variance in terms of GMd when comparing AF and srPA as predictors. Higher AF was associated with greater GMd in the cerebellum only, while srPA displayed positive associations with GMd in occipito-temporal, left perisylvian, and frontal regions after correcting for age. Importantly, only AF level, and not srPA, modified the relationship between age and GMd, such that higher levels of AF were associated with increased GMd in older age, while decreased GMd was seen in those with lower AF as a function of age. These results support existing literature suggesting that both AF and PA exert beneficial effects on GMd, but only AF served as a buffer against age-related GMd loss. Furthermore, these results highlight the need for use of objective PA measurement and comparability of tools across studies, since results vary dependent upon the measures used and whether these are objective or subjective in nature. PMID:25691866

  5. Differential Effects of E2 on MAPK Activity in the Brain and Heart of Aged Female Rats

    PubMed Central

    Shults, Cody L.; Rao, Yathindar S.; Pak, Toni R.

    2016-01-01

    Aging and the coincident loss of circulating estrogens at menopause lead to increased risks for neurological and cardiovascular pathologies. Clinical studies show that estrogen therapy (ET) can be beneficial in mitigating these negative effects, in both the brain and heart, when it is initiated shortly after the perimenopausal transition. However, this same therapy is detrimental when initiated >10 years postmenopause. Importantly, the molecular mechanisms underlying this age-related switch in ET efficacy are unknown. Estrogen receptors (ERs) mediate the neuroprotective and cardioprotective functions of estrogens by modulating gene transcription or, non-genomically, by activating second messenger signaling pathways, such as mitogen activated protein kinases (MAPK). These kinases are critical regulators of cell signaling pathways and have widespread downstream effects. Our hypothesis is that age and estrogen deprivation following menopause alters the expression and activation of the MAPK family members p38 and ERK in the brain and heart. To test this hypothesis, we used a surgically induced model of menopause in 18 month old rats through bilateral ovariectomy (OVX) followed by an acute dose of 17β-estradiol (E2) administered at varying time points post-OVX (1 week, 4 weeks, 8 weeks, or 12 weeks). Age and E2 treatment differentially regulated kinase activity in both the brain and heart, and the effects were also brain region specific. MAPK signaling plays an integral role in aging, and the aberrant regulation of those signaling pathways might be involved in age-related disorders. Clinical studies show benefits of ET during early menopause but detrimental effects later, which might be reflective of changes in kinase expression and activation status. PMID:27487271

  6. Age-related differential sensitivity to cadmium in Hyalella curvispina (Amphipoda) and implications in ecotoxicity studies.

    PubMed

    García, M E; Rodrígues Capítulo, A; Ferrari, L

    2010-07-01

    The standardization of toxicity tests requires the selection of the most suitable test species and their developmental stages, as well as the selection of the appropriate assay matrix and the evaluation of the sensitivity of the test species to the reference toxicants. International protocols recommend the use of the amphipod Hyalella azteca from the Northern Hemisphere for sediment toxicity tests. We selected the widely distributed amphipod Hyalella curvispina, representative of pleustonic, epiphitic and zoobenthic assemblages in austral South America, as test species to be used in regional studies. Our goals were to evaluate the sensitivity of three developmental stages of H. curvispina to cadmium as a reference toxicant and to select the most suitable age and exposure time for aquatic ecotoxicity assessment. The three ages were highly susceptible to cadmium, with sensitivities: neonates > adults > juveniles. Our results validate the use of the native H. curvispina as a standard species for ecotoxicological assessment studies.

  7. Differential range use between age classes of southern African Bearded Vultures Gypaetus barbatus.

    PubMed

    Krüger, Sonja; Reid, Timothy; Amar, Arjun

    2014-01-01

    Bearded Vulture Gypaetus barbatus movements were investigated in southern Africa to determine whether an individual's age, sex or breeding status influenced its ranging behaviour and to provide the information required to guide conservation activities. Data from satellite transmitters fitted to 18 individuals of four age classes were used to determine range size and use. Because of the nature of the movements of marked individuals, these data could be used to determine the overall foraging range of the entire population, which was estimated to be 51 767 km(2). Although juvenile, immature and sub-adult birds used different parts of the overall range, their combined foraging range was 65% (33 636 km(2)) of the overall range. Average adult home ranges (286 km(2)) were only around 1% the size of the average foraging ranges of non-adults (10 540 -25 985 km(2)), with those of breeding adults being even smaller (95 km(2)). Home ranges of breeding adults did not vary in size between seasons but adults utilized their home range more intensively whilst breeding, moving greater distances during the incubation and chick hatching period. Range size and use increased as non-adults aged. Immatures and sub-adults had larger range sizes during winter, but range use of non-adults did not vary seasonally. Range size and use did not differ between the sexes in any of the age classes. Information on home range size and use enables specific areas within the species' range to be targeted for management planning, education and conservation action.

  8. Differential Range Use between Age Classes of Southern African Bearded Vultures Gypaetus barbatus

    PubMed Central

    Krüger, Sonja; Reid, Timothy; Amar, Arjun

    2014-01-01

    Bearded Vulture Gypaetus barbatus movements were investigated in southern Africa to determine whether an individual's age, sex or breeding status influenced its ranging behaviour and to provide the information required to guide conservation activities. Data from satellite transmitters fitted to 18 individuals of four age classes were used to determine range size and use. Because of the nature of the movements of marked individuals, these data could be used to determine the overall foraging range of the entire population, which was estimated to be 51 767 km2. Although juvenile, immature and sub-adult birds used different parts of the overall range, their combined foraging range was 65% (33 636 km2) of the overall range. Average adult home ranges (286 km2) were only around 1% the size of the average foraging ranges of non-adults (10 540 –25 985 km2), with those of breeding adults being even smaller (95 km2). Home ranges of breeding adults did not vary in size between seasons but adults utilized their home range more intensively whilst breeding, moving greater distances during the incubation and chick hatching period. Range size and use increased as non-adults aged. Immatures and sub-adults had larger range sizes during winter, but range use of non-adults did not vary seasonally. Range size and use did not differ between the sexes in any of the age classes. Information on home range size and use enables specific areas within the species' range to be targeted for management planning, education and conservation action. PMID:25551614

  9. Modeling of Age-Dependent Epileptogenesis by Differential Homeostatic Synaptic Scaling.

    PubMed

    González, Oscar C; Krishnan, Giri P; Chauvette, Sylvain; Timofeev, Igor; Sejnowski, Terrence; Bazhenov, Maxim

    2015-09-30

    Homeostatic synaptic plasticity (HSP) has been implicated in the development of hyperexcitability and epileptic seizures following traumatic brain injury (TBI). Our in vivo experimental studies in cats revealed that the severity of TBI-mediated epileptogenesis depends on the age of the animal. To characterize mechanisms of these differences, we studied the properties of the TBI-induced epileptogenesis in a biophysically realistic cortical network model with dynamic ion concentrations. After deafferentation, which was induced by dissection of the afferent inputs, there was a reduction of the network activity and upregulation of excitatory connections leading to spontaneous spike-and-wave type seizures. When axonal sprouting was implemented, the seizure threshold increased in the model of young but not the older animals, which had slower or unidirectional homeostatic processes. Our study suggests that age-related changes in the HSP mechanisms are sufficient to explain the difference in the likelihood of seizure onset in young versus older animals. Significance statement: Traumatic brain injury (TBI) is one of the leading causes of intractable epilepsy. Likelihood of developing epilepsy and seizures following severe brain trauma has been shown to increase with age. Specific mechanisms of TBI-related epileptogenesis and how these mechanisms are affected by age remain to be understood. We test a hypothesis that the failure of homeostatic synaptic regulation, a slow negative feedback mechanism that maintains neural activity within a physiological range through activity-dependent modulation of synaptic strength, in older animals may augment TBI-induced epileptogenesis. Our results provide new insight into understanding this debilitating disorder and may lead to novel avenues for the development of effective treatments of TBI-induced epilepsy.

  10. Modeling of Age-Dependent Epileptogenesis by Differential Homeostatic Synaptic Scaling

    PubMed Central

    González, Oscar C.; Krishnan, Giri P.; Chauvette, Sylvain; Timofeev, Igor; Sejnowski, Terrence

    2015-01-01

    Homeostatic synaptic plasticity (HSP) has been implicated in the development of hyperexcitability and epileptic seizures following traumatic brain injury (TBI). Our in vivo experimental studies in cats revealed that the severity of TBI-mediated epileptogenesis depends on the age of the animal. To characterize mechanisms of these differences, we studied the properties of the TBI-induced epileptogenesis in a biophysically realistic cortical network model with dynamic ion concentrations. After deafferentation, which was induced by dissection of the afferent inputs, there was a reduction of the network activity and upregulation of excitatory connections leading to spontaneous spike-and-wave type seizures. When axonal sprouting was implemented, the seizure threshold increased in the model of young but not the older animals, which had slower or unidirectional homeostatic processes. Our study suggests that age-related changes in the HSP mechanisms are sufficient to explain the difference in the likelihood of seizure onset in young versus older animals. SIGNIFICANCE STATEMENT Traumatic brain injury (TBI) is one of the leading causes of intractable epilepsy. Likelihood of developing epilepsy and seizures following severe brain trauma has been shown to increase with age. Specific mechanisms of TBI-related epileptogenesis and how these mechanisms are affected by age remain to be understood. We test a hypothesis that the failure of homeostatic synaptic regulation, a slow negative feedback mechanism that maintains neural activity within a physiological range through activity-dependent modulation of synaptic strength, in older animals may augment TBI-induced epileptogenesis. Our results provide new insight into understanding this debilitating disorder and may lead to novel avenues for the development of effective treatments of TBI-induced epilepsy. PMID:26424890

  11. Differential Protein Distribution between the Nucleus and Mitochondria: Implications in Aging

    PubMed Central

    Lionaki, Eirini; Gkikas, Ilias; Tavernarakis, Nektarios

    2016-01-01

    The coordination of nuclear and mitochondrial genomes plays a pivotal role in maintenance of mitochondrial biogenesis and functionality during stress and aging. Environmental and cellular inputs signal to nucleus and/or mitochondria to trigger interorganellar compensatory responses. Loss of this tightly orchestrated coordination results in loss of cellular homeostasis and underlies various pathologies and age-related diseases. Several signaling cascades that govern interorganellar communication have been revealed up to now, and have been classified as part of the anterograde (nucleus to mitochondria) or retrograde (mitochondrial to nucleus) response. Many of these molecular pathways rely on the dual distribution of nuclear or mitochondrial components under basal or stress conditions. These dually localized components usually engage in specific tasks in their primary organelle of function, whilst upon cellular stimuli, they appear in the other organelle where they engage in the same or a different task, triggering a compensatory stress response. In this review, we focus on protein factors distributed between the nucleus and mitochondria and activated to exert their functions upon basal or stress conditions. We further discuss implications of bi-organellar targeting in the context of aging. PMID:27695477

  12. The semantic basis of taste-shape associations

    PubMed Central

    Woods, Andy T.; Marks, Lawrence E.; Cheok, Adrian David; Spence, Charles

    2016-01-01

    Previous research shows that people systematically match tastes with shapes. Here, we assess the extent to which matched taste and shape stimuli share a common semantic space and whether semantically congruent versus incongruent taste/shape associations can influence the speed with which people respond to both shapes and taste words. In Experiment 1, semantic differentiation was used to assess the semantic space of both taste words and shapes. The results suggest a common semantic space containing two principal components (seemingly, intensity and hedonics) and two principal clusters, one including round shapes and the taste word “sweet,” and the other including angular shapes and the taste words “salty,” “sour,” and “bitter.” The former cluster appears more positively-valenced whilst less potent than the latter. In Experiment 2, two speeded classification tasks assessed whether congruent versus incongruent mappings of stimuli and responses (e.g., sweet with round versus sweet with angular) would influence the speed of participants’ responding, to both shapes and taste words. The results revealed an overall effect of congruence with congruent trials yielding faster responses than their incongruent counterparts. These results are consistent with previous evidence suggesting a close relation (or crossmodal correspondence) between tastes and shape curvature that may derive from common semantic coding, perhaps along the intensity and hedonic dimensions. PMID:26966646

  13. Morning Cortisol Levels in Preschool-Aged Foster Children: Differential Effects of Maltreatment Type

    PubMed Central

    Bruce, Jacqueline; Fisher, Philip A.; Pears, Katherine C.; Levine, Seymour

    2008-01-01

    Maltreated foster children are subjected to a range of early adverse experiences, including neglect, abuse, and multiple caregiver disruptions. Research suggests that such disturbances alter the development and subsequent functioning of the hypothalamic-pituitary-adrenocortical system. The current study was designed to investigate morning cortisol levels in 117 foster children and 60 low-income, nonmaltreated children. Maltreatment and foster care placement experiences were coded from official records. Analyses revealed that the foster children were significantly more likely than the nonmaltreated children to have low morning cortisol levels. Additionally, specific maltreatment experiences were significantly associated with the foster children’s morning cortisol levels. Foster children with low morning cortisol levels experienced more severe physical neglect than the other foster children. In contrast, foster children with high morning cortisol levels experienced more severe emotional maltreatment. These results suggest that specific early adverse experiences have differential effects on the functioning of the hypothalamic-pituitary-adrenocortical system. PMID:18720365

  14. Lexical–semantic priming effects during infancy

    PubMed Central

    Arias-Trejo, Natalia; Plunkett, Kim

    2009-01-01

    When and how do infants develop a semantic system of words that are related to each other? We investigated word–word associations in early lexical development using an adaptation of the inter-modal preferential looking task where word pairs (as opposed to single target words) were used to direct infants’ attention towards a target picture. Two words (prime and target) were presented in quick succession after which infants were presented with a picture pair (target and distracter). Prime–target word pairs were either semantically and associatively related or unrelated; the targets were either named or unnamed. Experiment 1 demonstrated a lexical–semantic priming effect for 21-month olds but not for 18-month olds: unrelated prime words interfered with linguistic target identification for 21-month olds. Follow-up experiments confirmed the interfering effects of unrelated prime words and identified the existence of repetition priming effects as young as 18 months of age. The results of these experiments indicate that infants have begun to develop semantic–associative links between lexical items as early as 21 months of age. PMID:19933137

  15. Differential Changes with Age in Multiscale Entropy of Electromyography Signals from Leg Muscles during Treadmill Walking.

    PubMed

    Kang, Hyun Gu; Dingwell, Jonathan B

    2016-01-01

    Age-related gait changes may be due to the loss of complexity in the neuromuscular system. This theory is disputed due to inconsistent results from single-scale analyses. Also, behavioral adaptations may confound these changes. We examined whether EMG dynamics during gait is less complex in older adults over a range of timescales using the multiscale entropy method, and whether slower walking attenuates this effect. Surface EMG was measured from the left vastus lateralis (VL), biceps femoris (BF), gastrocnemius (GA), and tibialis anterior (TA) in 17 young and 18 older adults as they walked on a treadmill for 5 minutes at 0.8x-1.2x of preferred speed. Sample entropy (SE) and the complexity index (CI) of the EMG signals were calculated after successive coarse-graining to extract dynamics at timescales of 27 to 270 Hz, with m = 2 and r = 0.15 SD. SE and CI were lower across the timescales in older adults in VL and BF, but higher in GA (all p<0.001); these results held for VL and GA even after accounting for longer EMG burst durations in older adults. CI was higher during slower walking speed in VL and BF (p<0.001). Results were mostly similar for m = 3 and r = 0.01-0.35. Smaller r was more sensitive to age-related differences. The decrease in complexity with aging in the timescales studied was limited to proximal muscles, particularly VL. The increase in GA may be driven by other factors. Walking slower may reflect a behavioral adaptation that allows the nervous system to function with greater complexity.

  16. Differential Changes with Age in Multiscale Entropy of Electromyography Signals from Leg Muscles during Treadmill Walking

    PubMed Central

    Kang, Hyun Gu; Dingwell, Jonathan B.

    2016-01-01

    Age-related gait changes may be due to the loss of complexity in the neuromuscular system. This theory is disputed due to inconsistent results from single-scale analyses. Also, behavioral adaptations may confound these changes. We examined whether EMG dynamics during gait is less complex in older adults over a range of timescales using the multiscale entropy method, and whether slower walking attenuates this effect. Surface EMG was measured from the left vastus lateralis (VL), biceps femoris (BF), gastrocnemius (GA), and tibialis anterior (TA) in 17 young and 18 older adults as they walked on a treadmill for 5 minutes at 0.8x-1.2x of preferred speed. Sample entropy (SE) and the complexity index (CI) of the EMG signals were calculated after successive coarse-graining to extract dynamics at timescales of 27 to 270 Hz, with m = 2 and r = 0.15 SD. SE and CI were lower across the timescales in older adults in VL and BF, but higher in GA (all p<0.001); these results held for VL and GA even after accounting for longer EMG burst durations in older adults. CI was higher during slower walking speed in VL and BF (p<0.001). Results were mostly similar for m = 3 and r = 0.01–0.35. Smaller r was more sensitive to age-related differences. The decrease in complexity with aging in the timescales studied was limited to proximal muscles, particularly VL. The increase in GA may be driven by other factors. Walking slower may reflect a behavioral adaptation that allows the nervous system to function with greater complexity. PMID:27570974

  17. ADNP: A major autism mutated gene is differentially distributed (age and gender) in the songbird brain.

    PubMed

    Hacohen Kleiman, Gal; Barnea, Anat; Gozes, Illana

    2015-10-01

    ADNP is a protein necessary for brain development, important for brain plasticity, cognitive and social functioning, characteristics that are all impaired in autism and in the Adnp(+/-) mouse model, in a sex-dependent manner. ADNP was originally discovered as a protein that is secreted from glial cells in response to vasoactive intestinal peptide (VIP). VIP is a major neuroprotective peptide in the CNS and PNS and was also associated with social recognition in rodents and aggression, pair-bonding and parental behaviors in birds. Comparative sequence alignment revealed high evolutionary conservation of ADNP in Chordata. Despite its importance in brain function, ADNP has never been studied in birds. Zebra finches (Taeniopygia guttata) are highly social songbirds that have a sexually dichotomous anatomical brain structure, with males demonstrating a developed song system, presenting a model to study behavior and potential sexually dependent fundamental differences. Here, using quantitative real time polymerase chain reaction (qRT-PCR), we discovered sexually dichotomous and age related differences in ADNP mRNA expression in three different regions of the song bird brain-cerebellum, cerebrum, and brain stem. Higher levels of ADNP mRNA were specifically found in young male compared to the female cerebrum, while aging caused a significant 2 and 3-fold decrease in the female and male cerebrum, respectively. Furthermore, a comparison between the three tested brain regions revealed unique sex-dependent ADNP mRNA distribution patterns, affected by aging. Future studies are aimed at deciphering the function of ADNP in birds, toward a better molecular understanding of sexual dichotomy in singing behavior in birds.

  18. Early exposure to ethanol differentially affects ethanol preference at adult age in two inbred mouse strains.

    PubMed

    Molet, Jenny; Bouaziz, Elodie; Hamon, Michel; Lanfumey, Laurence

    2012-08-01

    Although the acute effects of ethanol exposure on brain development have been extensively studied, the long term consequences of juvenile ethanol intake on behavior at adult age, regarding especially ethanol consumption, are still poorly known. The aim of this study was to analyze the consequences of ethanol ingestion in juvenile C57BL/6J and DBA/2J mice on ethanol intake and neurobiological regulations at adulthood. Mice were given intragastric ethanol at 4 weeks of age under different protocols and their spontaneous ethanol consumption was assessed in a free choice paradigm at adulthood. Both serotonin 5-HT(1A) and cannabinoid CB1 receptors were investigated using [(35)S]GTP-γ-S binding assay for the juvenile ethanol regimens which modified adult ethanol consumption. In DBA/2J mice, juvenile ethanol ingestion dose-dependently promoted adult spontaneous ethanol consumption. This early ethanol exposure enhanced 5-HT(1A) autoreceptor-mediated [(35)S]GTP-γ-S binding in the dorsal raphe nucleus and reduced CB1 receptor-mediated G protein coupling in both the striatum and the globus pallidus at adult age. In contrast, early ethanol ingestion by C57BL/6J mice transiently lowered spontaneous ethanol consumption and increased G protein coupling of postsynaptic 5-HT(1A) receptors in the hippocampus but had no effect on CB1 receptors at adulthood. These results show that a brief and early exposure to ethanol can induce strain-dependent long-lasting changes in both behavior toward ethanol and key receptors of central 5-HT and CB systems in mice.

  19. Arithmetic knowledge in semantic dementia: is it invariably preserved?

    PubMed

    Julien, C L; Thompson, J C; Neary, D; Snowden, J S

    2008-09-01

    There is accumulating evidence of preserved arithmetic knowledge in semantic dementia (SD), contrasting with patients' striking impairment in other domains of semantic memory. This important finding exemplifies domain specificity in the breakdown of semantic memory and supports notions of the functional independence of semantic number knowledge. Nevertheless, evidence for preserved arithmetic knowledge in SD comes largely from single case studies. It is not known whether such preservation is a universal finding, or whether it persists irrespective of disease severity. The present study examined performance of 14 SD patients, varying in the severity of their semantic impairment, on tasks assessing knowledge of arithmetic signs, and on single-digit and multi-digit calculation problems, permitting evaluation of fact retrieval and use of procedures. SD patients performed generally well compared to 10 healthy controls on tests of addition and subtraction. However, abnormalities were elicited, which were not explained by education or hemispheric side of atrophy, but increased as a function of semantic severity. Patients had difficulty identifying arithmetic signs. They used increasingly basic, inflexible strategies to retrieve multiplication table 'facts', and in multi-digit calculations they made procedural errors that pointed to a failure to understand the differential weighting of left and right hand columns. The pattern of responses and error types mirrors in reverse that found in children as they acquire arithmetic competence, and suggests a progressive degradation in conceptual understanding of arithmetic. Longitudinal study of two SD patients demonstrated an association between semantic decline and impaired arithmetic performance. The findings challenge the notion of arithmetic knowledge as a totally separate semantic domain and suggest that the temporal lobes play an important role in arithmetic understanding.

  20. Development of Category-based Induction and Semantic Knowledge

    ERIC Educational Resources Information Center

    Fisher, Anna V.; Godwin, Karrie E.; Matlen, Bryan J.; Unger, Layla

    2015-01-01

    Category-based induction is a hallmark of mature cognition; however, little is known about its origins. This study evaluated the hypothesis that category-based induction is related to semantic development. Computational studies suggest that early on there is little differentiation among concepts, but learning and development lead to increased…

  1. Social Dialect, the Semantic Barrier, and Access to Curricular Knowledge.

    ERIC Educational Resources Information Center

    Corson, David

    1983-01-01

    The theory of the lexical bar is introduced, based on research in England and Australia. A semantic barrier exists in the English lexicon, separating the lexes of conservative peripheral dialects from those of dominant central dialects, producing differential educational attainment, and reproducing class-based division of labor. (MSE)

  2. Differential development of visual attention skills in school-age children

    PubMed Central

    Dye, Matthew W. G.; Bavelier, Daphne

    2009-01-01

    Children aged 7–17 years and adults aged 18–22 years were tested on three aspects of visual attention: the ability to distribute visual attention across the field to search for a target, the time required for attention to recover from being directed towards a target, and the number of objects to which attention can be simultaneously allocated. The data suggested different developmental trajectories for these components of visual attention within the same set of participants. This suggests that, to some extent, spatial, temporal and object-based attentional processes are subserved by different neural resources which develop at different rate. In addition, participants who played action games showed enhanced performance on all aspects of attention tested as compared to non-gamers. These findings reveal a potential facilitation of development of attentional skills in children who are avid players of action video games. As these games are predominantly drawing a male audience, young girls are at risk of underperforming on such tests, calling for a careful control of video game usage when assessing gender differences in attentional tasks. PMID:19836409

  3. Spatiotemporal Signatures of Lexical–Semantic Prediction

    PubMed Central

    Lau, Ellen F.; Weber, Kirsten; Gramfort, Alexandre; Hämäläinen, Matti S.; Kuperberg, Gina R.

    2016-01-01

    Although there is broad agreement that top-down expectations can facilitate lexical–semantic processing, the mechanisms driving these effects are still unclear. In particular, while previous electroencephalography (EEG) research has demonstrated a reduction in the N400 response to words in a supportive context, it is often challenging to dissociate facilitation due to bottom-up spreading activation from facilitation due to top-down expectations. The goal of the current study was to specifically determine the cortical areas associated with facilitation due to top-down prediction, using magnetoencephalography (MEG) recordings supplemented by EEG and functional magnetic resonance imaging (fMRI) in a semantic priming paradigm. In order to modulate expectation processes while holding context constant, we manipulated the proportion of related pairs across 2 blocks (10 and 50% related). Event-related potential results demonstrated a larger N400 reduction when a related word was predicted, and MEG source localization of activity in this time-window (350–450 ms) localized the differential responses to left anterior temporal cortex. fMRI data from the same participants support the MEG localization, showing contextual facilitation in left anterior superior temporal gyrus for the high expectation block only. Together, these results provide strong evidence that facilitatory effects of lexical–semantic prediction on the electrophysiological response 350–450 ms postonset reflect modulation of activity in left anterior temporal cortex. PMID:25316341

  4. A novel insight into Gene Ontology semantic similarity.

    PubMed

    Xu, Yungang; Guo, Maozu; Shi, Wenli; Liu, Xiaoyan; Wang, Chunyu

    2013-06-01

    Existing methods for computing the semantic similarity between Gene Ontology (GO) terms are often based on external datasets and, therefore are not intrinsic to GO. Furthermore, they not only fail to handle identical annotations but also show a strong bias toward well-annotated proteins when being used for measuring similarity of proteins. Inspired by the concept of cellular differentiation and dedifferentiation in developmental biology, we propose a shortest semantic differentiation distance (SSDD) based on the concept of semantic totipotency to measure the semantic similarity of GO terms and further compare the functional similarity of proteins. Using human ratings and a benchmark dataset, SSDD was found to improve upon existing methods for computing the semantic similarity of GO terms. An in-depth analysis shows that SSDD is able to distinguish identical annotations and does not depend on annotation richness, thus producing more unbiased and reliable results. Online services can be accessed at the Gene Functional Similarity Analysis Tools website (GFSAT: http://nclab.hit.edu.cn/GFSAT).

  5. Differentiated cytoplasmic granule formation in quiescent and non-quiescent cells upon chronological aging

    PubMed Central

    Lee, Hsin-Yi; Cheng, Kuo-Yu; Chao, Jung-Chi; Leu, Jun-Yi

    2016-01-01

    Stationary phase cultures represent a complicated cell population comprising at least two different cell types, quiescent (Q) and non-quiescent (NQ) cells. Q and NQ cells have different lifespans and cell physiologies. However, less is known about the organization of cytosolic protein structures in these two cell types. In this study, we examined Q and NQ cells for the formation of several stationary phase-prevalent granule structures including actin bodies, proteasome storage granules, stress granules, P-bodies, the compartment for unconventional protein secretion (CUPS), and Hsp42-associated stationary phase granules (Hsp42-SPGs). Most of these structures preferentially form in NQ cells, except for Hsp42-SPGs, which are enriched in Q cells. When nutrients are provided, NQ cells enter mitosis less efficiently than Q cells, likely due to the time requirement for reorganizing some granule structures. We observed that heat shock-induced misfolded proteins often colocalize to Hsp42-SPGs, and Q cells clear these protein aggregates more efficiently, suggesting that Hsp42-SPGs may play an important role in the stress resistance of Q cells. Finally, we show that the cell fate of NQ cells is largely irreversible even if they are allowed to reenter mitosis. Our results reveal that the formation of different granule structures may represent the early stage of cell type differentiation in yeast stationary phase cultures. PMID:28357341

  6. Differential Cysteine Labeling and Global Label-Free Proteomics Reveals an Altered Metabolic State in Skeletal Muscle Aging

    PubMed Central

    2014-01-01

    The molecular mechanisms underlying skeletal muscle aging and associated sarcopenia have been linked to an altered oxidative status of redox-sensitive proteins. Reactive oxygen and reactive nitrogen species (ROS/RNS) generated by contracting skeletal muscle are necessary for optimal protein function, signaling, and adaptation. To investigate the redox proteome of aging gastrocnemius muscles from adult and old male mice, we developed a label-free quantitative proteomic approach that includes a differential cysteine labeling step. The approach allows simultaneous identification of up- and downregulated proteins between samples in addition to the identification and relative quantification of the reversible oxidation state of susceptible redox cysteine residues. Results from muscles of adult and old mice indicate significant changes in the content of chaperone, glucose metabolism, and cytoskeletal regulatory proteins, including Protein DJ-1, cAMP-dependent protein kinase type II, 78 kDa glucose regulated protein, and a reduction in the number of redox-responsive proteins identified in muscle of old mice. Results demonstrate skeletal muscle aging causes a reduction in redox-sensitive proteins involved in the generation of precursor metabolites and energy metabolism, indicating a loss in the flexibility of the redox energy response. Data is available via ProteomeXchange with identifier PXD001054. PMID:25181601

  7. Differential cysteine labeling and global label-free proteomics reveals an altered metabolic state in skeletal muscle aging.

    PubMed

    McDonagh, Brian; Sakellariou, Giorgos K; Smith, Neil T; Brownridge, Philip; Jackson, Malcolm J

    2014-11-07

    The molecular mechanisms underlying skeletal muscle aging and associated sarcopenia have been linked to an altered oxidative status of redox-sensitive proteins. Reactive oxygen and reactive nitrogen species (ROS/RNS) generated by contracting skeletal muscle are necessary for optimal protein function, signaling, and adaptation. To investigate the redox proteome of aging gastrocnemius muscles from adult and old male mice, we developed a label-free quantitative proteomic approach that includes a differential cysteine labeling step. The approach allows simultaneous identification of up- and downregulated proteins between samples in addition to the identification and relative quantification of the reversible oxidation state of susceptible redox cysteine residues. Results from muscles of adult and old mice indicate significant changes in the content of chaperone, glucose metabolism, and cytoskeletal regulatory proteins, including Protein DJ-1, cAMP-dependent protein kinase type II, 78 kDa glucose regulated protein, and a reduction in the number of redox-responsive proteins identified in muscle of old mice. Results demonstrate skeletal muscle aging causes a reduction in redox-sensitive proteins involved in the generation of precursor metabolites and energy metabolism, indicating a loss in the flexibility of the redox energy response. Data is available via ProteomeXchange with identifier PXD001054.

  8. [Molecular diagnosis as a strategy for differential diagnosis and at early ages of neurofibromatosis type 1 (NF1)].

    PubMed

    Gómez, Martha; Batista, Oriana

    2015-10-01

    Neurofibromatosis type 1 (NF1), is a haploinsufficient and multisystemic disease, caused by inherited or sporadic mutations in the NF1 gene. Its incidence is one in 2,500 to 3,000 individuals, it has an autosomal dominant pattern of inheritance, high clinical variability, complete penetrance and age-dependent complications. Neurofibromin is the product of the NF1 gene and is believed to act as a tumor suppressor since the loss of its function has been associated with benign and malignant tumors in neural crest-derived tissues. Only two correlations between clinical phenotype and mutant alleles in the NF1 gene have been observed. The established criteria for disease diagnosis are very efficient in adults and children older than 3 years of age, but not for children under this age. Mutational analysis is therefore recommended to confirm the disease in young children with a negative family history. A pathogenic mutation in the NF1 should be added to the list of diagnostic criteria. Mutational analysis is also recommended for differential diagnosis and for prenatal or pre-implantation genetic diagnosis, taking into consideration the family history and the type of method to be applied. Molecular studies of this disease using different complimentary molecular techniques and bioinformatics tools have characterized NF1 gene mutations at both the DNA and mRNA levels, increasing the mutational spectrum. Consequently, about 1,289 defects have been reported to date, mainly nonsense/missense mutations, deletions and splice site defects.

  9. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  10. The UMLS Semantic Network and the Semantic Web.

    PubMed

    Kashyap, Vipul

    2003-01-01

    The Unified Medical Language System is an extensive source of biomedical knowledge developed and maintained by the US National Library of Medicine (NLM) and is being currently used in a wide variety of biomedical applications. The Semantic Network, a component of the UMLS is a structured description of core biomedical knowledge consisting of well defined semantic types and relationships between them. We investigate the expressiveness of DAML+OIL, a markup language proposed for ontologies on the Semantic Web, for representing the knowledge contained in the Semantic Network. Requirements specific to the Semantic Network, such as polymorphic relationships and blocking relationship inheritance are discussed and approaches to represent these in DAML+OIL are presented. Finally, conclusions are presented along with a discussion of ongoing and future work.

  11. Depth of Processing and Age Differences.

    PubMed

    Kheirzadeh, Shiela; Pakzadian, Sarah Sadat

    2016-10-01

    The present article is aimed to investigate whether there are any differences between youngsters and adults in their working and long-term memory functioning. The theory of Depth of Processing (Craik and Lockhart in J Verbal Learning Verbal Behav 11:671-684, 1972) discusses the varying degrees of strengths of memory traces as the result of differential levels of processing on the retrieved input. Additionally, they claim that there are three levels of visual, auditory and semantic processes applied on the stimuli in the short-term memory leading to discrepancy in the durability of the memory traces and the later ease of recall and retrieval. In the present article, it is tried to demonstrate if there are evidences of more durable memory traces formed after semantic, visual and auditory processions of the incoming language data in two groups of (a) children in their language learning critical age and (b) youngsters who have passed the critical age period. The comparisons of the results made using two-way ANOVAs revealed the superiority of semantic processing for both age groups in recall, retention and consequently recognition of the new English vocabularies by EFL learners.

  12. The age of the martian meteorite Northwest Africa 1195 and the differentiation history of the shergottites

    SciTech Connect

    Symes, S; Borg, L; Shearer, C; Irving, A

    2007-04-05

    Samarium-neodymium isotopic analyses of unleached and acid-leached mineral fractions from the recently identified olivine-bearing shergottite Northwest Africa 1195 yield a crystallization age of 348 {+-} 19 Ma and an {var_epsilon}{sub Nd}{sup 143} value of +40.1 {+-} 1.3. Maskelynite fractions do not lie on the Sm-Nd isochron and appear to contain a martian surface component with low {sup 147}Sm/{sup 144}Nd and {sup 143}Nd/{sup 144}Nd ratios that was added during shock. The Rb-Sr system is disturbed and does not yield an isochron. Terrestrial Sr appears to have affected all of the mineral fractions, although a maximum initial {sup 87}Sr/{sup 86}Sr ratio of 0.701614 {+-} 16 is estimated by passing a 348 Ma reference isochron through the maskelynite fraction that is least affected by contamination. The high initial {var_epsilon}{sub Nd}{sup 143} value and the low initial {sup 87}Sr/{sup 86}Sr ratio, combined with the geologically young crystallization age, indicate that Northwest Africa 1195 is derived from a source region characterized by a long-term incompatible element depletion. The age and initial Sr and Nd isotopic compositions of Northwest Africa 1195 are very similar to those of Queen Alexandra Range 94201, indicating these samples were derived from source regions with nearly identical Sr-Nd isotopic systematics. These similarities suggest that these two meteorites share a close petrogenetic relationship and might have been erupted from a common volcano. The meteorites Yamato 980459, Dar al Gani 476, Sayh al Uhaymir 005/008, and Dhofar 019 also have relatively old ages between 474-575 Ma and trace element and/or isotopic systematics that are indicative of derivation from incompatible-element-depleted sources. This suggests that the oldest group of meteorites is more closely related to one another than they are to the younger meteorites that are derived from less incompatible-element-depleted sources. Closed-system fractional crystallization of this suite of

  13. The age of the martian meteorite Northwest Africa 1195 and the differentiation history of the shergottites

    NASA Astrophysics Data System (ADS)

    Symes, Steven J. K.; Borg, Lars E.; Shearer, Charles K.; Irving, Anthony J.

    2008-03-01

    Samarium-neodymium isotopic analyses of unleached and acid-leached mineral fractions from the recently identified olivine-bearing shergottite Northwest Africa 1195 yield a crystallization age of 347 ± 13 Ma and an ɛNd143 value of +40.1 ± 0.9. Maskelynite fractions do not lie on the Sm-Nd isochron and appear to contain a martian surface component with low 147Sm/ 144Nd and 143Nd/ 144Nd ratios that was added during shock. The Rb-Sr system is disturbed and does not yield an isochron. Terrestrial Sr appears to have affected all of the mineral fractions, although a maximum initial 87Sr/ 86Sr ratio of 0.7016 is estimated by passing a 347 Ma reference line through the maskelynite fraction that is least affected by contamination. The high initial ɛNd143 value and the low initial 87Sr/ 86Sr ratio, combined with the geologically young crystallization age, indicate that Northwest Africa 1195 is derived from a source region characterized by a long-term incompatible-element depletion. The age and initial Sr and Nd isotopic compositions of Northwest Africa 1195 are very similar to those of Queen Alexandra Range 94201, indicating these samples were derived from source regions with similar Sr-Nd isotopic systematics. These similarities suggest that these two meteorites share a close petrogenetic relationship and might have been erupted from a common volcano. The meteorites Yamato 980459, Dar al Gani 476, Sayh al Uhaymir 005/008, and Dhofar 019 also have relatively old ages between 474 and 575 Ma and trace element and/or isotopic systematics that are indicative of derivation from incompatible-element-depleted sources. This suggests that the oldest group of meteorites is more closely related to one another than they are to the younger meteorites that are derived from less incompatible-element-depleted sources. Closed-system fractional crystallization of this suite of meteorites is modeled with the MELTS algorithm using the bulk composition of Yamato 980459 as a parent. These

  14. Age differential response of Hyalella curvispina to a cadmium pulse: influence of sediment particle size.

    PubMed

    García, M E; Rodrígues Capítulo, A; Ferrari, L

    2012-06-01

    In Argentina periurban streams frequently receive agricultural, livestock and industrial discharges. Heavy metals have been found in the water column and sediments of numerous water bodies of the pampean region, at levels above the limits established for aquatic life protection. This study aimed to evaluate the effect of a contaminant pulse of cadmium discharged into a water-sediment system of different particle sizes, by means of laboratory tests using juveniles and adults of Hyalella curvispina, a native amphipod. We found that the substrate particle size was a determining factor in the toxicity of cadmium and that the adults of H. curvispina were more sensitive than juveniles. We also observed a temporal difference between the two ages for the same type of sediment. Given the nature of the sediments of regional water bodies, it is expected that a discharge of cadmium, even at concentrations as low as those tested here, will affect the survival of native amphipods.

  15. Two cases of food aversion with semantic dementia

    PubMed Central

    Thompson, Alexandra E.; Clark, Camilla N.; Hardy, Christopher J.; Fletcher, Phillip D.; Greene, John; Rohrer, Jonathan D.; Warren, Jason D.

    2016-01-01

    ABSTRACT Accounts of altered eating behavior in semantic dementia generally emphasize gluttony and abnormal food preferences. Here we describe two female patients with no past history of eating disorders who developed early prominent aversion to food in the context of an otherwise typical semantic dementia syndrome. One patient (aged 57) presented features in line with anorexia nervosa while the second patient (aged 58) presented with a syndrome more suggestive of bulimia nervosa. These cases add to the growing spectrum of apparently dichotomous behavior patterns in the frontotemporal dementias and illustrate a potentially under-recognized cause of eating disorders presenting in later life. PMID:26963051

  16. Daily Socs1 rhythms alter with aging differentially in peripheral clocks in male Wistar rats: therapeutic effects of melatonin.

    PubMed

    Vinod, Ch; Jagota, Anita

    2017-03-22

    resulted in differential restoration of rSocs1 rhythms and levels in various tissues of 24 months old group. The sensitivity of 24 months old animals to melatonin found in the present study is a step towards endorsing melatonin as an important anti-aging therapeutic drug.

  17. Orthographic Learning in Learning to Spell: The Roles of Semantics and Type of Practice

    ERIC Educational Resources Information Center

    Ouellette, Gene

    2010-01-01

    This study investigated the relevance of type of practice and presence of semantic representation for orthographic learning in learning to spell. A total of 36 students in Grade 2 (mean age = 7 years 10 months) were exposed to 10 novel nonwords, 5 of which were paired with semantic information. Half of the participants practiced reading these new…

  18. Episodic and Semantic Autobiographical Memory in Adults with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Crane, Laura; Goddard, Lorna

    2008-01-01

    Episodic and semantic autobiographical memories were examined in a group of adults with autism spectrum disorders (ASD) and a control group matched for age, gender and IQ. Results demonstrated a personal episodic memory deficit in the ASD group in the absence of a personal semantic memory deficit, suggesting a deficit dissociation between these…

  19. Lexical Organization in Deaf Children Who Use British Sign Language: Evidence from a Semantic Fluency Task

    ERIC Educational Resources Information Center

    Marshall, Chloe R.; Rowley, Katherine; Mason, Kathryn; Herman, Rosalind; Morgan, Gary

    2013-01-01

    We adapted the semantic fluency task into British Sign Language (BSL). In Study 1, we present data from twenty-two deaf signers aged four to fifteen. We show that the same "cognitive signatures" that characterize this task in spoken languages are also present in deaf children, for example, the semantic clustering of responses. In Study…

  20. The Role of Self-Teaching in Learning Orthographic and Semantic Aspects of New Words

    ERIC Educational Resources Information Center

    Ricketts, Jessie; Bishop, Dorothy V. M.; Pimperton, Hannah; Nation, Kate

    2011-01-01

    This study explores how children learn the meaning (semantics) and spelling patterns (orthography) of novel words encountered in story context. English-speaking children (N = 88) aged 7 to 8 years read 8 stories and each story contained 1 novel word repeated 4 times. Semantic cues were provided by the story context such that children could infer…

  1. The semantic and episodic subcomponents of famous person knowledge: dissociation in healthy subjects.

    PubMed

    Piolino, Pascale; Lamidey, Virginie; Desgranges, Béatrice; Eustache, Francis

    2007-01-01

    Fifty-two subjects between ages 40 and 79 years were administered a questionnaire assessing their ability to recall semantic information about famous people from 4 different decades and to recollect its episodic source of acquisition together with autonoetic consciousness via the remember-know paradigm. In addition, they underwent a battery of standardized neuropsychological tests to assess episodic and semantic memory and executive functions. The analyses of age reveal differences for the episodic source score but no differences between age groups for the semantic scores within each decade. Regardless of the age of people, the analyses also show that semantic memory subcomponents of the famous person test are highly associated with each other as well as with the source component. The recall of semantic information on the famous person test relies on participants' semantic abilities, whereas the recall of its episodic source depends on their executive functions. The present findings confirm the existence of an episodic-semantic distinction in knowledge about famous people. They provide further evidence that personal source and semantic information are at once distinct and highly interactive within the framework of remote memory.

  2. Semantic Feature Distinctiveness and Frequency

    ERIC Educational Resources Information Center

    Lamb, Katherine M.

    2012-01-01

    Lexical access is the process in which basic components of meaning in language, the lexical entries (words) are activated. This activation is based on the organization and representational structure of the lexical entries. Semantic features of words, which are the prominent semantic characteristics of a word concept, provide important information…

  3. Semantic Research for Digital Libraries.

    ERIC Educational Resources Information Center

    Chen, Hsinchun

    1999-01-01

    Discusses the need for semantic research in digital libraries to help overcome interoperability problems. Highlights include federal initiatives; semantic analysis; knowledge representations; human-computer interactions and information visualization; and the University of Illinois DLI (Digital Libraries Initiative) project through partnership with…

  4. Semantic Tools in Information Retrieval.

    ERIC Educational Resources Information Center

    Rubinoff, Morris; Stone, Don C.

    This report discusses the problem of the meansings of words used in information retrieval systems, and shows how semantic tools can aid in the communication which takes place between indexers and searchers via index terms. After treating the differing use of semantic tools in different types of systems, two tools (classification tables and…

  5. Indexing by Latent Semantic Analysis.

    ERIC Educational Resources Information Center

    Deerwester, Scott; And Others

    1990-01-01

    Describes a new method for automatic indexing and retrieval called latent semantic indexing (LSI). Problems with matching query words with document words in term-based information retrieval systems are discussed, semantic structure is examined, singular value decomposition (SVD) is explained, and the mathematics underlying the SVD model is…

  6. Semantic Processing of Mathematical Gestures

    ERIC Educational Resources Information Center

    Lim, Vanessa K.; Wilson, Anna J.; Hamm, Jeff P.; Phillips, Nicola; Iwabuchi, Sarina J.; Corballis, Michael C.; Arzarello, Ferdinando; Thomas, Michael O. J.

    2009-01-01

    Objective: To examine whether or not university mathematics students semantically process gestures depicting mathematical functions (mathematical gestures) similarly to the way they process action gestures and sentences. Semantic processing was indexed by the N400 effect. Results: The N400 effect elicited by words primed with mathematical gestures…

  7. Information tables with neighborhood semantics

    NASA Astrophysics Data System (ADS)

    Yao, Yiyu

    2000-04-01

    Information tables provide a convenient and useful tool for representing a set of objects using a group of attributes. This notion is enriched by introducing neighborhood systems on attribute values. The neighborhood systems represent the semantics relationships between, and knowledge about, attribute values. With added semantics, neighborhood based information tables may provide a more general framework for knowledge discovery, data mining, and information retrieval.

  8. The semantic planetary data system

    NASA Technical Reports Server (NTRS)

    Hughes, J. Steven; Crichton, Daniel; Kelly, Sean; Mattmann, Chris

    2005-01-01

    This paper will provide a brief overview of the PDS data model and the PDS catalog. It will then describe the implentation of the Semantic PDS including the development of the formal ontology, the generation of RDFS/XML and RDF/XML data sets, and the buiding of the semantic search application.

  9. Receptive vocabulary and semantic knowledge in children with SLI and children with Down syndrome.

    PubMed

    Laws, Glynis; Briscoe, Josie; Ang, Su-Yin; Brown, Heather; Hermena, Ehab; Kapikian, Anna

    2015-01-01

    Receptive vocabulary and associated semantic knowledge were compared within and between groups of children with specific language impairment (SLI), children with Down syndrome (DS), and typically developing children. To overcome the potential confounding effects of speech or language difficulties on verbal tests of semantic knowledge, a novel task was devised based on picture-based semantic association tests used to assess adult patients with semantic dementia. Receptive vocabulary, measured by word-picture matching, of children with SLI was weak relative to chronological age and to nonverbal mental age but their semantic knowledge, probed across the same lexical items, did not differ significantly from that of vocabulary-matched typically developing children. By contrast, although receptive vocabulary of children with DS was a relative strength compared to nonverbal cognitive abilities (p < .0001), DS was associated with a significant deficit in semantic knowledge (p < .0001) indicative of dissociation between word-picture matching vocabulary and depth of semantic knowledge. Overall, these data challenge the integrity of semantic-conceptual development in DS and imply that contemporary theories of semantic cognition should also seek to incorporate evidence from atypical conceptual development.

  10. Using Histopathologic Evidence to Differentiate Reproductive Senescence from Xenobiotic Effects in Middle-aged Female Sprague-Dawley Rats.

    PubMed

    Shirai, Norimitsu; Houle, Christopher; Mirsky, Michael L

    2015-12-01

    The female reproductive cycle is orchestrated by cyclical and coordinated hormonal changes under the direction of the hypothalamic-pituitary-gonadal (HPG) axis. Any disruption of the HPG axis may lead to functional and structural alterations in the female reproductive system. Test article-related disturbances in the estrous cycle can be recognized in nonclinical toxicity studies by staging the cycle based on microscopic evaluation of female reproductive organs. In chronic rat toxicity studies, an additional complication is the development of reproductive senescence, which is associated with natural alterations in the reproductive cycle leading to changes in the female reproductive system that can potentially be confused with test article effects. The current article describes the features of persistent estrus, one stage of reproductive senescence, in middle-aged Sprague-Dawley rats and discusses elements to help differentiate senescence from induced effects.

  11. [Semantic information. Internal language. Thinking].

    PubMed

    Azcoaga, J E

    1993-06-01

    Semantic information has reached an objective condition after a lengthy history of semantic inquiries that instrumental neurophysiological devices--such as event-related potentials, electroencephalographic spectral analysis, regional brain circulation, PET scan, deep brain electrodes, and other--have made easier. In turn, internal language, as screened according to Vigotsky's perspective, is considered a product of semantic information circulation understood as neurosemae interconnection. Finally, in normal adults, thinking processes are assumed to be made up by both sensoperceptive information (proprioceptive information included) and semantic information. Thus, an "extraverbal thinking" can be distinguished, whose activity is hardly describable in healthy adults but should be considered as a condition of non-educated deaf persons, and a "verbal thinking", or internal language, made up by semantic information.

  12. Hierarchical abstract semantic model for image classification

    NASA Astrophysics Data System (ADS)

    Ye, Zhipeng; Liu, Peng; Zhao, Wei; Tang, Xianglong

    2015-09-01

    Semantic gap limits the performance of bag-of-visual-words. To deal with this problem, a hierarchical abstract semantics method that builds abstract semantic layers, generates semantic visual vocabularies, measures semantic gap, and constructs classifiers using the Adaboost strategy is proposed. First, abstract semantic layers are proposed to narrow the semantic gap between visual features and their interpretation. Then semantic visual words are extracted as features to train semantic classifiers. One popular form of measurement is used to quantify the semantic gap. The Adaboost training strategy is used to combine weak classifiers into strong ones to further improve performance. For a testing image, the category is estimated layer-by-layer. Corresponding abstract hierarchical structures for popular datasets, including Caltech-101 and MSRC, are proposed for evaluation. The experimental results show that the proposed method is capable of narrowing semantic gaps effectively and performs better than other categorization methods.

  13. Audio-Visual and Meaningful Semantic Context Enhancements in Older and Younger Adults

    PubMed Central

    Smayda, Kirsten E.; Van Engen, Kristin J.; Maddox, W. Todd; Chandrasekaran, Bharath

    2016-01-01

    Speech perception is critical to everyday life. Oftentimes noise can degrade a speech signal; however, because of the cues available to the listener, such as visual and semantic cues, noise rarely prevents conversations from continuing. The interaction of visual and semantic cues in aiding speech perception has been studied in young adults, but the extent to which these two cues interact for older adults has not been studied. To investigate the effect of visual and semantic cues on speech perception in older and younger adults, we recruited forty-five young adults (ages 18–35) and thirty-three older adults (ages 60–90) to participate in a speech perception task. Participants were presented with semantically meaningful and anomalous sentences in audio-only and audio-visual conditions. We hypothesized that young adults would outperform older adults across SNRs, modalities, and semantic contexts. In addition, we hypothesized that both young and older adults would receive a greater benefit from a semantically meaningful context in the audio-visual relative to audio-only modality. We predicted that young adults would receive greater visual benefit in semantically meaningful contexts relative to anomalous contexts. However, we predicted that older adults could receive a greater visual benefit in either semantically meaningful or anomalous contexts. Results suggested that in the most supportive context, that is, semantically meaningful sentences presented in the audiovisual modality, older adults performed similarly to young adults. In addition, both groups received the same amount of visual and meaningful benefit. Lastly, across groups, a semantically meaningful context provided more benefit in the audio-visual modality relative to the audio-only modality, and the presence of visual cues provided more benefit in semantically meaningful contexts relative to anomalous contexts. These results suggest that older adults can perceive speech as well as younger adults when

  14. Etiological Subgroups of Small-for-Gestational-Age: Differential Neurodevelopmental Outcomes

    PubMed Central

    Li, Xiuhong; Eiden, Rina D.; Epstein, Leonard H.; Shenassa, Edmond D.; Xie, Chuanbo; Wen, Xiaozhong

    2016-01-01

    Objectives It remains unclear why substantial variations in neurodevelopmental outcomes exist within small-for-gestational-age (SGA) children. We prospectively compared 5-y neurodevelopmental outcomes across SGA etiological subgroups. Methods Children born SGA (N = 1050) from U.S. Early Childhood Longitudinal Study-Birth Cohort (2001–2007) was divided into etiological subgroups by each of 7 well-established prenatal risk factors. We fit linear regression models to compare 5-y reading, math, gross motor and fine motor scores across SGA subgroups, adjusting for socio-demographic confounders. Results Compared to singleton SGA subgroup, multiple-birth SGA subgroup had lower mean reading (adjusted mean difference, -4.08 [95% confidence interval, -6.10, -2.06]) and math (-2.22 [-3.61, -0.84]) scores. These disadvantages in reading and math existed only among multiple-birth SGA subgroup without ovulation stimulation (reading, -4.50 [-6.64, -2.36]; math, -2.91 [-4.37, -1.44]), but not among those with ovulation stimulation (reading, -2.33 [-6.24, 1.57]; math 0.63 [-1.86, 3.12]). Compared to singleton SGA subgroup without maternal smoking and inadequate gestational weight gain, singleton SGA subgroup with co-occurrence of maternal smoking and inadequate gestational weight gain (GWG) had lower mean reading (-4.81 [-8.50, -1.12]) and math (-2.95 [-5.51, -0.38]) scores. These differences were not mediated by Apgar score. Conclusions Multiple-birth SGA subgroups (vs. singleton SGA) or singleton SGA subgroup with co-occurrence of smoking and inadequate GWG (vs. singleton SGA subgroup without maternal smoking and inadequate gestational weight gain) have poorer cognitive development up to 5 y. PMID:27501456

  15. Distributed Semantic Overlay Networks

    NASA Astrophysics Data System (ADS)

    Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Vazirgiannis, Michalis

    Semantic Overlay Networks (SONs) have been recently proposed as a way to organize content in peer-to-peer (P2P) networks. The main objective is to discover peers with similar content and then form thematically focused peer groups. Efficient content retrieval can be performed by having queries selectively forwarded only to relevant groups of peers to the query. As a result, less peers need to be contacted, in order to answer a query. In this context, the challenge is to generate SONs in a decentralized and distributed manner, as the centralized assembly of global information is not feasible. Different approaches for exploiting the generated SONs for content retrieval have been proposed in the literature, which are examined in this chapter, with a particular focus on SON interconnections for efficient search. Several applications, such as P2P document and image retrieval, can be deployed over generated SONs, motivating the need for distributed and truly scalable SON creation. Therefore, recently several research papers focus on SONs as stated in our comprehensive overview of related work in the field of semantic overlay networks. A classification of existing algorithms according to a set of qualitative criteria is also provided. In spite of the rich existing work in the field of SONs, several challenges have not been efficiently addressed yet, therefore, future promising research directions are pointed out and discussed at the end of this chapter.

  16. Semantic Workflows and Provenance

    NASA Astrophysics Data System (ADS)

    Gil, Y.

    2011-12-01

    While sharing and disseminating data is widely practiced across scientific communities, we have yet to recognize the importance of sharing and disseminating the analytic processes that leads to published data. Data retrieved from shared repositories and archives is often hard to interpret because we lack documentation about those processes: what models were used, what assumptions were made, what calibrations were carried out, etc. This process documentation is also key to aggregate data in a meaningful way, whether aggregating shared third party data or aggregating shared data with local sensor data collected by individual investigators. We suggest that augmenting published data with process documentation would greatly enhance our ability to find, reuse, interpret, and aggregate data and therefore have a significant impact in the utility of data repositories and archives. We will show that semantic workflows and provenance provide key technologies for capturing process documentation. Semantic workflows describe the kinds of data transformation and analysis steps used to create new data products, and can include useful constraints about why specific models were selected or parameters chosen. Provenance records can be used to publish workflow descriptions in standard formats that can be reused to enable verification and reproducibility of data products.

  17. "Pre-Semantic" Cognition Revisited: Critical Differences between Semantic Aphasia and Semantic Dementia

    ERIC Educational Resources Information Center

    Jefferies, Elizabeth; Rogers, Timothy T.; Hopper, Samantha; Lambon Ralph, Matthew A.

    2010-01-01

    Patients with semantic dementia show a specific pattern of impairment on both verbal and non-verbal "pre-semantic" tasks, e.g., reading aloud, past tense generation, spelling to dictation, lexical decision, object decision, colour decision and delayed picture copying. All seven tasks are characterised by poorer performance for items that are…

  18. Differential Insulitic Profiles Determine the Extent of β-Cell Destruction and the Age at Onset of Type 1 Diabetes.

    PubMed

    Leete, Pia; Willcox, Abby; Krogvold, Lars; Dahl-Jørgensen, Knut; Foulis, Alan K; Richardson, Sarah J; Morgan, Noel G

    2016-05-01

    Type 1 diabetes (T1D) results from a T cell-mediated destruction of pancreatic β-cells following the infiltration of leukocytes (including CD8(+), CD4(+), and CD20(+) cells) into and around pancreatic islets (insulitis). Recently, we reported that two distinct patterns of insulitis occur in patients with recent-onset T1D from the U.K. and that these differ principally in the proportion of infiltrating CD20(+) B cells (designated CD20Hi and CD20Lo, respectively). We have now extended this analysis to include patients from the Network for Pancreatic Organ Donors with Diabetes (U.S.) and Diabetes Virus Detection (DiViD) study (Norway) cohorts and confirm that the two profiles of insulitis occur more widely. Moreover, we show that patients can be directly stratified according to their insulitic profile and that those receiving a diagnosis before the age of 7 years always display the CD20Hi profile. By contrast, individuals who received a diagnosis beyond the age of 13 years are uniformly defined as CD20Lo. This implies that the two forms of insulitis are differentially aggressive and that patients with a CD20Hi profile lose their β-cells at a more rapid rate. In support of this, we also find that the proportion of residual insulin-containing islets (ICIs) increases in parallel with age at the onset of T1D. Importantly, those receiving a diagnosis in, or beyond, their teenage years retain ∼40% ICIs at diagnosis, implying that a functional deficit rather than an absolute β-cell loss may be causal for disease onset in these patients. We conclude that appropriate patient stratification will be critical for correct interpretation of the outcomes of intervention therapies targeted to islet-infiltrating immune cells in T1D.

  19. Generalisation of fear and avoidance along a semantic continuum.

    PubMed

    Boyle, Sean; Roche, Bryan; Dymond, Simon; Hermans, Dirk

    2016-01-01

    Directly conditioned fear and avoidance readily generalises to dissimilar but conceptually related stimuli. Here, for the first time, we examined the conceptual/semantic generalisation of both fear and avoidance using real words (synonyms). Participants were first exposed to a differential fear conditioning procedure in which one word (e.g., "broth"; CS+) was followed with brief electric shock [unconditioned stimulus (US)] and another was not (e.g., "assist"; CS-). Next, an instrumental conditioning phase taught avoidance in the presence the CS+ but not the CS-. During generalisation testing, synonyms of the CS+ (e.g., "soup"; GCS+) and CS- (e.g., "help"; GCS-) were presented in the absence of shock. Conditioned fear and avoidance, measured via skin conductance responses, behavioural avoidance and US expectancy ratings, generalised to the semantically related, but not to the semantically unrelated, synonyms. Findings have implications for how natural language categories and concepts mediate the expansion of fear and avoidance repertoires in clinical contexts.

  20. High density ERP indices of conscious and unconscious semantic priming.

    PubMed

    Ruz, María; Madrid, Eduardo; Lupiáñez, Juan; Tudela, Pío

    2003-10-01

    The existence of differential brain mechanisms of conscious and unconscious processing is a matter of debate nowadays. The present experiment explores whether conscious and unconscious semantic priming in a lexical decision task at a long prime-target stimulus onset asynchrony (SOA) correlate with overlapping or different event related potential (ERP) effects. Results show that the N400 effect, which appeared when words were consciously perceived, completely disappeared when primes were masked at a level where the ability of participants to detect the prime was near chance. Instead, a rather different set of ERP effects was found to index unconscious semantic priming. This suggests that the processes at the basis of conscious and unconscious semantic analyses can under some circumstances be rather different. Moreover, our results support the notion that conscious and unconscious processes are at least partially separable in the brain.

  1. Semantic Representation and Naming in Young Children.

    ERIC Educational Resources Information Center

    McGregor, Karla K.; Friedman, Rena M.; Reilly, Renee M.; Newman, Robyn M.

    2002-01-01

    Two experiments examined children's semantic representations and semantic naming errors. Results suggested that functional and physical properties are core aspects of object representations in the semantic lexicon and that the degree of semantic knowledge makes words more or less vulnerable to retrieval failure. Discussion focuses on the dynamic…

  2. The Semantic Distance Model of Relevance Assessment.

    ERIC Educational Resources Information Center

    Brooks, Terrence A.

    1998-01-01

    Presents the Semantic Distance Model (SDM) of Relevance Assessment, a cognitive model of the relationship between semantic distance and relevance assessment. Discusses premises of the model such as the subjective nature of information and the metaphor of semantic distance. Empirical results illustrate the effects of semantic distance and semantic…

  3. Mapping the Structure of Semantic Memory

    ERIC Educational Resources Information Center

    Morais, Ana Sofia; Olsson, Henrik; Schooler, Lael J.

    2013-01-01

    Aggregating snippets from the semantic memories of many individuals may not yield a good map of an individual's semantic memory. The authors analyze the structure of semantic networks that they sampled from individuals through a new snowball sampling paradigm during approximately 6 weeks of 1-hr daily sessions. The semantic networks of individuals…

  4. Exploiting Recurring Structure in a Semantic Network

    NASA Technical Reports Server (NTRS)

    Wolfe, Shawn R.; Keller, Richard M.

    2004-01-01

    With the growing popularity of the Semantic Web, an increasing amount of information is becoming available in machine interpretable, semantically structured networks. Within these semantic networks are recurring structures that could be mined by existing or novel knowledge discovery methods. The mining of these semantic structures represents an interesting area that focuses on mining both for and from the Semantic Web, with surprising applicability to problems confronting the developers of Semantic Web applications. In this paper, we present representative examples of recurring structures and show how these structures could be used to increase the utility of a semantic repository deployed at NASA.

  5. Workspaces in the Semantic Web

    NASA Technical Reports Server (NTRS)

    Wolfe, Shawn R.; Keller, RIchard M.

    2005-01-01

    Due to the recency and relatively limited adoption of Semantic Web technologies. practical issues related to technology scaling have received less attention than foundational issues. Nonetheless, these issues must be addressed if the Semantic Web is to realize its full potential. In particular, we concentrate on the lack of scoping methods that reduce the size of semantic information spaces so they are more efficient to work with and more relevant to an agent's needs. We provide some intuition to motivate the need for such reduced information spaces, called workspaces, give a formal definition, and suggest possible methods of deriving them.

  6. High Performance Descriptive Semantic Analysis of Semantic Graph Databases

    SciTech Connect

    Joslyn, Cliff A.; Adolf, Robert D.; al-Saffar, Sinan; Feo, John T.; Haglin, David J.; Mackey, Greg E.; Mizell, David W.

    2011-06-02

    As semantic graph database technology grows to address components ranging from extant large triple stores to SPARQL endpoints over SQL-structured relational databases, it will become increasingly important to be able to understand their inherent semantic structure, whether codified in explicit ontologies or not. Our group is researching novel methods for what we call descriptive semantic analysis of RDF triplestores, to serve purposes of analysis, interpretation, visualization, and optimization. But data size and computational complexity makes it increasingly necessary to bring high performance computational resources to bear on this task. Our research group built a novel high performance hybrid system comprising computational capability for semantic graph database processing utilizing the large multi-threaded architecture of the Cray XMT platform, conventional servers, and large data stores. In this paper we describe that architecture and our methods, and present the results of our analyses of basic properties, connected components, namespace interaction, and typed paths such for the Billion Triple Challenge 2010 dataset.

  7. Quasi-programmed aging of budding yeast: a trade-off between programmed processes of cell proliferation, differentiation, stress response, survival and death defines yeast lifespan.

    PubMed

    Arlia-Ciommo, Anthony; Piano, Amanda; Leonov, Anna; Svistkova, Veronika; Titorenko, Vladimir I

    2014-01-01

    Recent findings suggest that evolutionarily distant organisms share the key features of the aging process and exhibit similar mechanisms of its modulation by certain genetic, dietary and pharmacological interventions. The scope of this review is to analyze mechanisms that in the yeast Saccharomyces cerevisiae underlie: (1) the replicative and chronological modes of aging; (2) the convergence of these 2 modes of aging into a single aging process; (3) a programmed differentiation of aging cell communities in liquid media and on solid surfaces; and (4) longevity-defining responses of cells to some chemical compounds released to an ecosystem by other organisms populating it. Based on such analysis, we conclude that all these mechanisms are programs for upholding the long-term survival of the entire yeast population inhabiting an ecological niche; however, none of these mechanisms is a "program of aging" - i.e., a program for progressing through consecutive steps of the aging process.

  8. Quasi-programmed aging of budding yeast: a trade-off between programmed processes of cell proliferation, differentiation, stress response, survival and death defines yeast lifespan

    PubMed Central

    Arlia-Ciommo, Anthony; Piano, Amanda; Leonov, Anna; Svistkova, Veronika; Titorenko, Vladimir I

    2014-01-01

    Recent findings suggest that evolutionarily distant organisms share the key features of the aging process and exhibit similar mechanisms of its modulation by certain genetic, dietary and pharmacological interventions. The scope of this review is to analyze mechanisms that in the yeast Saccharomyces cerevisiae underlie: (1) the replicative and chronological modes of aging; (2) the convergence of these 2 modes of aging into a single aging process; (3) a programmed differentiation of aging cell communities in liquid media and on solid surfaces; and (4) longevity-defining responses of cells to some chemical compounds released to an ecosystem by other organisms populating it. Based on such analysis, we conclude that all these mechanisms are programs for upholding the long-term survival of the entire yeast population inhabiting an ecological niche; however, none of these mechanisms is a ʺprogram of agingʺ - i.e., a program for progressing through consecutive steps of the aging process. PMID:25485579

  9. The Influence of rTMS over Prefrontal and Motor Areas in a Morphological Task: Grammatical vs. Semantic Effects

    ERIC Educational Resources Information Center

    LoGerfo, Emanuele; Oliveri, Massimiliano; Torriero, Sara; Salerno, Silvia; Koch, Giacomo; Caltagirone, Carlo

    2008-01-01

    We investigated the differential role of two frontal regions in the processing of grammatical and semantic knowledge. Given the documented specificity of the prefrontal cortex for the grammatical class of verbs, and of the primary motor cortex for the semantic class of action words, we sought to investigate whether the prefrontal cortex is also…

  10. Altered semantic integration in autism beyond language: a cross-modal event-related potentials study.

    PubMed

    Ribeiro, Tatiane C; Valasek, Claudia A; Minati, Ludovico; Boggio, Paulo S

    2013-05-29

    Autism spectrum disorders (ASDs) are characterized by impaired communication, particularly pragmatic and semantic language, resulting in verbal comprehension deficits. Semantic processing in these conditions has been studied extensively, but mostly limited only to linguistic material. Emerging evidence, however, suggests that semantic integration deficits may extend beyond the verbal domain. Here, we explored cross-modal semantic integration using visual targets preceded by musical and linguistic cues. Particularly, we have recorded the event-related potentials to evaluate whether the N400 and late positive potential (LPP) components, two widely studied electrophysiological markers of semantic processing, are differently sensitive to congruence with respect to typically developing children. Seven ASD patients and seven neurotypical participants matched by age, education and intelligence quotient provided usable data. Neuroelectric activity was recorded in response to visual targets that were related or unrelated to a preceding spoken sentence or musical excerpt. The N400 was sensitive to semantic congruence in the controls but not the patients, whereas the LPP showed a complementary pattern. These results suggest that semantic processing in ASD children is also altered in the context of musical and visual stimuli, and point to a functional decoupling between the generators of the N400 and LPP, which may indicate delayed semantic processing. These novel findings underline the importance of exploring semantic integration across multiple modalities in ASDs and provide motivation for further investigation in large clinical samples.

  11. Does semantic redundancy gain result from multiple semantic priming?

    PubMed

    Schröter, Hannes; Bratzke, Daniel; Fiedler, Anja; Birngruber, Teresa

    2015-10-01

    Fiedler, Schröter, and Ulrich (2013) reported faster responses to a single written word when the semantic content of this word (e.g., "elephant") matched both targets (e.g., "animal", "gray") as compared to a single target (e.g., "animal", "brown"). This semantic redundancy gain was explained by statistical facilitation due to a race of independent memory retrieval processes. The present experiment addresses one alternative explanation, namely that semantic redundancy gain results from multiple pre-activation of words that match both targets. In different blocks of trials, participants performed a redundant-targets task and a lexical decision task. The targets of the redundant-targets task served as primes in the lexical decision task. Replicating the findings of Fiedler et al., a semantic redundancy gain was observed in the redundant-targets task. Crucially, however, there was no evidence of a multiple semantic priming effect in the lexical decision task. This result suggests that semantic redundancy gain cannot be explained by multiple pre-activation of words that match both targets.

  12. Lexical-Semantic Organization in Children with Specific Language Impairment

    ERIC Educational Resources Information Center

    Sheng, Li; McGregor, Karla K.

    2010-01-01

    Purpose: To determine whether children with specific language impairment (SLI) show deficits in lexical-semantic organization and, if so, whether these deficits are commensurate with their delay in vocabulary size and whether the deficits affect all children with SLI. Method: Fourteen children with SLI, 14 age matches (AM), and 14 expressive…

  13. Phonological and Semantic Priming in Children with Reading Disability

    ERIC Educational Resources Information Center

    Betjemann, Rebecca S.; Keenan, Janice M.

    2008-01-01

    Lexical priming was assessed in children with reading disability (RD) and in age-matched controls (M= 11.5 years), in visual and auditory lexical decision tasks. In the visual task, children with RD were found to have deficits in semantic (SHIP-BOAT), phonological/graphemic (GOAT-BOAT), and combined (FLOAT-BOAT) priming. The same pattern of…

  14. Children's Communication of Basic Level and Subordinate Level Semantic Contrasts.

    ERIC Educational Resources Information Center

    Kossan, Nancy E.

    Developmental differences in preschool children's abilities to communicate about basic and subordinate level semantic contrasts were examined in a referential communication situation. Twenty-four three, four, and five-year-old children communicated with children of the same age and adults about pictures' referents. Speakers talked about one…

  15. Verbal Memory and Semantic Organization of Children with Learning Disabilities

    ERIC Educational Resources Information Center

    Polychroni, Fotini; Economou, Alexandra; Printezi, Anna; Koutlidi, Ifigeneia

    2011-01-01

    The present study examined the verbal learning performance and the semantic organization used by Greek reading-disabled readers as compared to a control group using a list-learning task. The sample consisted of 45 elementary school children with reading difficulties and 45 comparison children matched for age and gender. Tests of reading ability,…

  16. Problem Solving with General Semantics.

    ERIC Educational Resources Information Center

    Hewson, David

    1996-01-01

    Discusses how to use general semantics formulations to improve problem solving at home or at work--methods come from the areas of artificial intelligence/computer science, engineering, operations research, and psychology. (PA)

  17. Nine Principles of Semantic Harmonization.

    PubMed

    Cunningham, James A; Van Speybroeck, Michel; Kalra, Dipak; Verbeeck, Rudi

    2016-01-01

    Medical data is routinely collected, stored and recorded across different institutions and in a range of different formats. Semantic harmonization is the process of collating this data into a singular consistent logical view, with many approaches to harmonizing both possible and valid. The broad scope of possibilities for undertaking semantic harmonization do lead however to the development of bespoke and ad-hoc systems; this is particularly the case when it comes to cohort data, the format of which is often specific to a cohort's area of focus. Guided by work we have undertaken in developing the 'EMIF Knowledge Object Library', a semantic harmonization framework underpinning the collation of pan-European Alzheimer's cohort data, we have developed a set of nine generic guiding principles for developing semantic harmonization frameworks, the application of which will establish a solid base for constructing similar frameworks.

  18. Nine Principles of Semantic Harmonization

    PubMed Central

    Cunningham, James A.; Van Speybroeck, Michel; Kalra, Dipak; Verbeeck, Rudi

    2016-01-01

    Medical data is routinely collected, stored and recorded across different institutions and in a range of different formats. Semantic harmonization is the process of collating this data into a singular consistent logical view, with many approaches to harmonizing both possible and valid. The broad scope of possibilities for undertaking semantic harmonization do lead however to the development of bespoke and ad-hoc systems; this is particularly the case when it comes to cohort data, the format of which is often specific to a cohort’s area of focus. Guided by work we have undertaken in developing the ‘EMIF Knowledge Object Library’, a semantic harmonization framework underpinning the collation of pan-European Alzheimer’s cohort data, we have developed a set of nine generic guiding principles for developing semantic harmonization frameworks, the application of which will establish a solid base for constructing similar frameworks. PMID:28269840

  19. Distributed semantic networks and CLIPS

    NASA Technical Reports Server (NTRS)

    Snyder, James; Rodriguez, Tony

    1991-01-01

    Semantic networks of frames are commonly used as a method of reasoning in many problems. In most of these applications the semantic network exists as a single entity in a single process environment. Advances in workstation hardware provide support for more sophisticated applications involving multiple processes, interacting in a distributed environment. In these applications the semantic network may well be distributed over several concurrently executing tasks. This paper describes the design and implementation of a frame based, distributed semantic network in which frames are accessed both through C Language Integrated Production System (CLIPS) expert systems and procedural C++ language programs. The application area is a knowledge based, cooperative decision making model utilizing both rule based and procedural experts.

  20. NASA and The Semantic Web

    NASA Technical Reports Server (NTRS)

    Ashish, Naveen

    2005-01-01

    We provide an overview of several ongoing NASA endeavors based on concepts, systems, and technology from the Semantic Web arena. Indeed NASA has been one of the early adopters of Semantic Web Technology and we describe ongoing and completed R&D efforts for several applications ranging from collaborative systems to airspace information management to enterprise search to scientific information gathering and discovery systems at NASA.

  1. Semantic Interoperability on the Web

    DTIC Science & Technology

    2000-01-01

    these agents would not be affected by presentation changes if the pages were available in XML, they would still break if the XML representation of the... these semantics into tools that are used to interpret or translate the XML documents, but software tools cannot acquire these semantics independently...mapping differences in naming conventions. As with natural language, XML DTDs have the problems of polysemy and synonymy. For example, the elements

  2. Neural substrates of semantic memory.

    PubMed

    Hart, John; Anand, Raksha; Zoccoli, Sandra; Maguire, Mandy; Gamino, Jacque; Tillman, Gail; King, Richard; Kraut, Michael A

    2007-09-01

    Semantic memory is described as the storage of knowledge, concepts, and information that is common and relatively consistent across individuals (e.g., memory of what is a cup). These memories are stored in multiple sensorimotor modalities and cognitive systems throughout the brain (e.g., how a cup is held and manipulated, the texture of a cup's surface, its shape, its function, that is related to beverages such as coffee, and so on). Our ability to engage in purposeful interactions with our environment is dependent on the ability to understand the meaning and significance of the objects and actions around us that are stored in semantic memory. Theories of the neural basis of the semantic memory of objects have produced sophisticated models that have incorporated to varying degrees the results of cognitive and neural investigations. The models are grouped into those that are (1) cognitive models, where the neural data are used to reveal dissociations in semantic memory after a brain lesion occurs; (2) models that incorporate both cognitive and neuroanatomical information; and (3) models that use cognitive, neuroanatomic, and neurophysiological data. This review highlights the advances and issues that have emerged from these models and points to future directions that provide opportunities to extend these models. The models of object memory generally describe how category and/or feature representations encode for object memory, and the semantic operations engaged in object processing. The incorporation of data derived from multiple modalities of investigation can lead to detailed neural specifications of semantic memory organization. The addition of neurophysiological data can potentially provide further elaboration of models to include semantic neural mechanisms. Future directions should incorporate available and newly developed techniques to better inform the neural underpinning of semantic memory models.

  3. Dissociating the effects of semantic grouping and rehearsal strategies on event-related brain potentials.

    PubMed

    Schleepen, T M J; Markus, C R; Jonkman, L M

    2014-12-01

    The application of elaborative encoding strategies during learning, such as grouping items on similar semantic categories, increases the likelihood of later recall. Previous studies have suggested that stimuli that encourage semantic grouping strategies had modulating effects on specific ERP components. However, these studies did not differentiate between ERP activation patterns evoked by elaborative working memory strategies like semantic grouping and more simple strategies like rote rehearsal. Identification of neurocognitive correlates underlying successful use of elaborative strategies is important to understand better why certain populations, like children or elderly people, have problems applying such strategies. To compare ERP activation during the application of elaborative versus more simple strategies subjects had to encode either four semantically related or unrelated pictures by respectively applying a semantic category grouping or a simple rehearsal strategy. Another goal was to investigate if maintenance of semantically grouped vs. ungrouped pictures modulated ERP-slow waves differently. At the behavioral level there was only a semantic grouping benefit in terms of faster responding on correct rejections (i.e. when the memory probe stimulus was not part of the memory set). At the neural level, during encoding semantic grouping only had a modest specific modulatory effect on a fronto-central Late Positive Component (LPC), emerging around 650 ms. Other ERP components (i.e. P200, N400 and a second Late Positive Component) that had been earlier related to semantic grouping encoding processes now showed stronger modulation by rehearsal than by semantic grouping. During maintenance semantic grouping had specific modulatory effects on left and right frontal slow wave activity. These results stress the importance of careful control of strategy use when investigating the neural correlates of elaborative encoding.

  4. Semantic preview benefit during reading.

    PubMed

    Hohenstein, Sven; Kliegl, Reinhold

    2014-01-01

    Word features in parafoveal vision influence eye movements during reading. The question of whether readers extract semantic information from parafoveal words was studied in 3 experiments by using a gaze-contingent display change technique. Subjects read German sentences containing 1 of several preview words that were replaced by a target word during the saccade to the preview (boundary paradigm). In the 1st experiment the preview word was semantically related or unrelated to the target. Fixation durations on the target were shorter for semantically related than unrelated previews, consistent with a semantic preview benefit. In the 2nd experiment, half the sentences were presented following the rules of German spelling (i.e., previews and targets were printed with an initial capital letter), and the other half were presented completely in lowercase. A semantic preview benefit was obtained under both conditions. In the 3rd experiment, we introduced 2 further preview conditions, an identical word and a pronounceable nonword, while also manipulating the text contrast. Whereas the contrast had negligible effects, fixation durations on the target were reliably different for all 4 types of preview. Semantic preview benefits were greater for pretarget fixations closer to the boundary (large preview space) and, although not as consistently, for long pretarget fixation durations (long preview time). The results constrain theoretical proposals about eye movement control in reading. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  5. Differential Development of Inflammation and Insulin Resistance in Different Adipose Tissue Depots Along Aging in Wistar Rats: Effects of Caloric Restriction.

    PubMed

    Sierra Rojas, Johanna X; García-San Frutos, Miriam; Horrillo, Daniel; Lauzurica, Nuria; Oliveros, Eva; Carrascosa, Jose María; Fernández-Agulló, Teresa; Ros, Manuel

    2016-03-01

    The prevalence of insulin resistance and type 2 diabetes increases with aging and these disorders are associated with inflammation. Insulin resistance and inflammation do not develop at the same time in all tissues. Adipose tissue is one of the tissues where inflammation and insulin resistance are established earlier during aging. Nevertheless, the existence of different fat depots states the possibility of differential roles for these depots in the development of age-associated inflammation and insulin resistance. To explore this, we analyzed insulin signaling and inflammation in epididymal, perirenal, subcutaneous, and brown adipose tissues during aging in Wistar rats. Although all tissues showed signs of inflammation and insulin resistance with aging, epididymal fat was the first to develop signs of inflammation and insulin resistance along aging among white fat tissues. Subcutaneous adipose tissue presented the lowest degree of inflammation and insulin resistance that developed latter with age. Brown adipose tissue also presented latter insulin resistance and inflammation but with lower signs of macrophage infiltration. Caloric restriction ameliorated insulin resistance and inflammation in all tissues, being more effective in subcutaneous and brown adipose tissues. These data demonstrate differential susceptibility of the different adipose depots to the development of age-associated insulin resistance and inflammation.

  6. Differential Prediction of Alcohol vs. Hard Drug Use Levels in a General Youth Sample via the HEW Youth Development Model's Community Youth Program Impact Scales, Age, and Sex.

    ERIC Educational Resources Information Center

    Truckenmiller, James L.

    Recent national surveys have found marked increases in the use of illicit drugs and alcohol among adolescents. To investigate differential prediction of alcohol versus hard drug use amoung youths, 6% of the youths, aged 10-19, from a Pennsylvania county school system (N=1,689) were assessed on the HEW Community Youth Program Impact Scales. The 12…

  7. Anomia: a doubly typical signature of semantic dementia.

    PubMed

    Woollams, Anna M; Cooper-Pye, Elisa; Hodges, John R; Patterson, Karalyn

    2008-08-01

    This study was designed to explore the nature of the anomia that is a defining feature of semantic dementia. Using a pool of 225 sets of picture naming data from 78 patients, we assessed the effects on naming accuracy of several characteristics of the target objects or their names: familiarity, frequency, age of acquisition and semantic domain (living/non-living). We also analysed the distribution of different error types according to the severity of the naming deficit. A particular focus of the study was the impact on naming of a previously unconsidered variable: the typicality of an object within its semantic category. This factor had a major influence both on naming success and on the proportions of different error types. Moreover, and increasingly so with declining naming accuracy, the patients' single-word incorrect responses were more typical than the target names. The observed effects of typicality sit well within models of semantic memory that represent concepts in terms of patterns of co-occurrence of constituent features. The results add to a growing body of evidence that, throughout the progressive deterioration of conceptual knowledge that characterises semantic dementia, both accuracy of performance and the nature of error responses are increasingly determined by the domain-specific aspects of typicality relevant to the task in question.

  8. Episodic and semantic memory in bilingual and monolingual children.

    PubMed

    Kormi-Nouri, Reza; Moniri, Sadegheh; Nilsson, Lars-Göran

    2003-02-01

    Although bilinguality has been reported to confer advantages upon children with respect to various cognitive abilities, much less is known about the relation between memory and bilinguality. In this study, 60 (30 girls and 30 boys) bilingual and 60 (30 girls and 30 boys) monolingual children in three age groups (mean ages 8.5, 10.5 and 12.5 years) were compared on episodic memory and semantic memory tasks. Episodic memory was assessed using subject-performed tasks (with real or imaginary objects) and verbal tasks, with retrieval by both free recall and cued recall. Semantic memory was assessed by word fluency tests. Positive effects of bilingualism were found on both episodic memory and semantic memory at all age levels. These findings suggest that bilingual children integrate and/or organize the information of two languages, and so bilingualism creates advantages in terms of cognitive abilities (including memory). Some sex differences were also found in episodic memory but not in semantic memory. This episodic memory difference was found with younger children.

  9. Semantic Processing in Deaf and Hard-of-Hearing Children: Large N400 Mismatch Effects in Brain Responses, Despite Poor Semantic Ability

    PubMed Central

    Kallioinen, Petter; Olofsson, Jonas; Nakeva von Mentzer, Cecilia; Lindgren, Magnus; Ors, Marianne; Sahlén, Birgitta S.; Lyxell, Björn; Engström, Elisabet; Uhlén, Inger

    2016-01-01

    Difficulties in auditory and phonological processing affect semantic processing in speech comprehension for deaf and hard-of-hearing (DHH) children. However, little is known about brain responses related to semantic processing in this group. We investigated event-related potentials (ERPs) in DHH children with cochlear implants (CIs) and/or hearing aids (HAs), and in normally hearing controls (NH). We used a semantic priming task with spoken word primes followed by picture targets. In both DHH children and controls, cortical response differences between matching and mismatching targets revealed a typical N400 effect associated with semantic processing. Children with CI had the largest mismatch response despite poor semantic abilities overall; Children with CI also had the largest ERP differentiation between mismatch types, with small effects in within-category mismatch trials (target from same category as prime) and large effects in between-category mismatch trials (where target is from a different category than prime), compared to matching trials. Children with NH and HA had similar responses to both mismatch types. While the large and differentiated ERP responses in the CI group were unexpected and should be interpreted with caution, the results could reflect less precision in semantic processing among children with CI, or a stronger reliance on predictive processing. PMID:27559320

  10. Soluble cluster of differentiation 36 concentrations are not associated with cardiovascular risk factors in middle-aged subjects

    PubMed Central

    ALKHATATBEH, MOHAMMAD J.; AYOUB, NEHAD M.; MHAIDAT, NIZAR M.; SAADEH, NESREEN A.; LINCZ, LISA F.

    2016-01-01

    Cluster of differentiation 36 (CD36) is involved in the development of atherosclerosis by enhancing macrophage endocytosis of oxidized low-density lipoproteins and foam cell formation. Soluble CD36 (sCD36) was found to be elevated in type 2 diabetic patients and possibly acted as a marker of insulin resistance and atherosclerosis. In young subjects, sCD36 was associated with cardiovascular risk factors including obesity and hypertriglyceridemia. The present study was conducted to further investigate the association between plasma sCD36 and cardiovascular risk factors among middle-aged patients with metabolic syndrome (MetS) and healthy controls. sCD36 concentrations were determined by enzyme-linked immunosorbent assays (ELISA) for 41 patients with MetS and 36 healthy controls. Data for other variables were obtained from patient medical records. sCD36 concentrations were relatively low compared to the majority of other studies and were not significantly different between the MetS group and controls (P=0.17). sCD36 was also not correlated with age, body mass index, glucose, lipid profile, serum electrolytes and blood counts. sCD36 was not significantly different between subjects with obesity, hyperglycemia, dyslipidemia, hypertension or cardiovascular disease, and those without these abnormalities (P>0.05). The inconsistency between results reported in the present study and other studies may be unique to the study population or be a result of the lack of a reliable standardized method for determining absolute sCD36 concentrations. However, further investigations are required to assess CD36 tissue expression in the study population and to assess the accuracy of various commercially available sCD36 ELISA kits. Thus, the availability of a standardized simple sCD36 ELISA that could be performed in any basic laboratory would be more favorable to the specialized flow cytometry methods that detect CD36+ microparticles if it was to be used as a biomarker. PMID:27123261

  11. Semantic Services for Wikipedia

    NASA Astrophysics Data System (ADS)

    Wang, Haofen; Penin, Thomas; Fu, Linyun; Liu, Qiaoling; Xue, Guirong; Yu, Yong

    Wikipedia, a killer application in Web 2.0, has embraced the power of collaborative editing to harness collective intelligence. It features many attractive characteristics, like entity-based link graph, abundant categorization and semi-structured layout, and can serve as an ideal data source to extract high quality and well-structured data. In this chapter, we first propose several solutions to extract knowledge from Wikipedia. We do not only consider information from the relational summaries of articles (infoboxes) but also semi-automatically extract it from the article text using the structured content available. Due to differences with information extraction from the Web, it is necessary to tackle new problems, like the lack of redundancy in Wikipedia that is dealt with by extending traditional machine learning algorithms to work with few labeled data. Furthermore, we also exploit the widespread categories as a complementary way to discover additional knowledge. Benefiting from both structured and textural information, we additionally provide a suggestion service for Wikipedia authoring. With the aim to facilitate semantic reuse, our proposal provides users with facilities such as link, categories and infobox content suggestions. The proposed enhancements can be applied to attract more contributors and lighten the burden of professional editors. Finally, we developed an enhanced search system, which can ease the process of exploiting Wikipedia. To provide a user-friendly interface, it extends the faceted search interface with relation navigation and let the user easily express his complex information needs in an interactive way. In order to achieve efficient query answering, it extends scalable IR engines to index and search both the textual and structured information with an integrated ranking support.

  12. Visual Discrimination Predicts Naming and Semantic Association Accuracy in Alzheimer’s Disease

    PubMed Central

    Harnish, Stacy M.; Neils-Strunjas, Jean; Eliassen, James; Reilly, Jamie; Meinzer, Marcus; Clark, John Greer; Joseph, Jane

    2010-01-01

    Objective Language impairment is a common symptom of Alzheimer’s disease (AD) and is thought to be related to semantic processing. The present study examines the contribution of another process, namely visual perception, on measures of confrontation naming and semantic association abilities in persons with probable AD. Methods Twenty individuals with probable mild-moderate Alzheimer’s disease and twenty age-matched controls completed a battery of neuropsychological measures assessing visual perception, naming, and semantic association ability. Visual discrimination tasks that varied in the degree to which they likely accessed stored structural representations were used to gauge whether structural processing deficits could account for deficits in naming and in semantic association in AD. Results Visual discrimination abilities of nameable objects in AD strongly predicted performance on both picture naming and semantic association ability but lacked the same predictive value for controls. Although impaired, performance on visual discrimination tests of abstract shapes and novel faces showed no significant relationship with picture naming and semantic association. These results provide additional evidence to support that structural processing deficits exist in AD and may contribute to object recognition and naming deficits. Conclusions Our findings suggest that there is a common deficit in discrimination of pictures using nameable objects, picture naming and semantic association of pictures in AD. Disturbances in structural processing of pictured items may be associated with lexical-semantic impairment in AD due to degraded internal storage of structural knowledge. PMID:21042208

  13. Metaphor, Metonymy, and Their Interaction in the Production of Semantic Approximations by Monolingual Children: A Corpus Analysis

    ERIC Educational Resources Information Center

    Pérez-Hernández, Lorena; Duvignau, Karine

    2016-01-01

    The present study looks into the largely unexplored territory of the cognitive underpinnings of semantic approximations in child language. The analysis of a corpus of 233 semantic approximations produced by 101 monolingual French-speaking children from 1;8 to 4;2 years of age leads to a classification of a significant number of them as instances…

  14. Semantic processing of crowded stimuli?

    PubMed

    Huckauf, Anke; Knops, Andre; Nuerk, Hans-Christoph; Willmes, Klaus

    2008-11-01

    Effects of semantic processing of crowded characters were investigated using numbers as stimuli. In an identification task, typical spacing effects in crowding were replicated. Using the same stimuli in a magnitude comparison task, a smaller effect of spacing was observed as well as an effect of response congruency. These effects were replicated in a second experiment with varying stimulus-onset asynchronies. In addition, decreasing performance with increasing onset-asynchrony (so-called type-B masking) for incongruent flankers indicates semantic processing of target and flankers. The data show that semantic processing takes place even in crowded stimuli. This argues strongly against common accounts of crowding in terms of early stimulus-driven impairments of processing.

  15. Ontology Matching with Semantic Verification

    PubMed Central

    Jean-Mary, Yves R.; Shironoshita, E. Patrick; Kabuka, Mansur R.

    2009-01-01

    ASMOV (Automated Semantic Matching of Ontologies with Verification) is a novel algorithm that uses lexical and structural characteristics of two ontologies to iteratively calculate a similarity measure between them, derives an alignment, and then verifies it to ensure that it does not contain semantic inconsistencies. In this paper, we describe the ASMOV algorithm, and then present experimental results that measure its accuracy using the OAEI 2008 tests, and that evaluate its use with two different thesauri: WordNet, and the Unified Medical Language System (UMLS). These results show the increased accuracy obtained by combining lexical, structural and extensional matchers with semantic verification, and demonstrate the advantage of using a domain-specific thesaurus for the alignment of specialized ontologies. PMID:20186256

  16. Semantic Web Research Trends and Directions

    DTIC Science & Technology

    2006-01-01

    social trust on the semantic web that builds upon the previous work to create end user applications that benefit from the semantic foundation. 2 Swoop...security, authentication, and privacy. However, the social component of trust is one that is both important and ideally suited for the Semantic Web. When the...Semantic Web-based social networks are augmented with trust information, it is possible to make computations over the values, and integrate the

  17. Nicotine effects on general semantic priming in Parkinson's disease.

    PubMed

    Holmes, Anna D; Copland, David A; Silburn, Peter A; Chenery, Helen J

    2011-06-01

    In young healthy nonsmokers, effects of nicotine on semantic processing have been observed under strategy-based priming procedures but not under more general priming procedures (Holmes, Chenery, & Copland, 2008; Holmes, Chenery, & Copland, 2010). Effects of nicotine under general priming procedures, however, may be mediated by baseline priming levels that are below optimum such as when compromised by disease. Nicotinic mechanisms may be involved in the cognitive sequalae of Parkinson's disease (PD). Evidence suggests that semantic processing may be compromised in PD but the potential benefit of nicotinic stimulation is unknown. This study investigated the effects of nicotine on semantic processing in nonsmokers with PD (n = 12) and nonsmoking matched controls (n = 17) using general priming procedures. Specifically, an automatic priming task (0.15 relatedness proportion, RP, and 200 ms stimulus onset asynchrony, SOA) and a controlled priming task (0.8 RP and 1000 ms SOA) were used. Prime-target category relation (category related, noncategory related) was also manipulated. Transdermal nicotine patches (7 mg/24 h) were administered in a double-blind, placebo-controlled, crossover design. For the automatic task, nicotine did not influence priming effects for PD. Unexpectedly, compromised automatic priming for controls was ameliorated. For the controlled task, nicotine influenced priming effects for PD but not controls. The patterns of priming and nicotine effects across the tasks suggest an age-related slowing of the rate of semantic activation for controls, which may be exacerbated in PD. Overall, the findings indicate that nicotine can improve compromised semantic processing in PD, and also influence semantic processing in healthy older individuals.

  18. Semantic processing in information retrieval.

    PubMed Central

    Rindflesch, T. C.; Aronson, A. R.

    1993-01-01

    Intuition suggests that one way to enhance the information retrieval process would be the use of phrases to characterize the contents of text. A number of researchers, however, have noted that phrases alone do not improve retrieval effectiveness. In this paper we briefly review the use of phrases in information retrieval and then suggest extensions to this paradigm using semantic information. We claim that semantic processing, which can be viewed as expressing relations between the concepts represented by phrases, will in fact enhance retrieval effectiveness. The availability of the UMLS domain model, which we exploit extensively, significantly contributes to the feasibility of this processing. PMID:8130547

  19. Bootstrapping to a Semantic Grid

    SciTech Connect

    Schwidder, Jens; Talbott, Tara; Myers, James D.

    2005-02-28

    The Scientific Annotation Middleware (SAM) is a set of components and services that enable researchers, applications, problem solving environments (PSE) and software agents to create metadata and annotations about data objects and document the semantic relationships between them. Developed starting in 2001, SAM allows applications to encode metadata within files or to manage metadata at the level of individual relationships as desired. SAM then provides mechanisms to expose metadata and relation¬ships encoded either way as WebDAV properties. In this paper, we report on work to further map this metadata into RDF and discuss the role of middleware such as SAM in bridging between traditional and semantic grid applications.

  20. Language networks in semantic dementia.

    PubMed

    Agosta, Federica; Henry, Roland G; Migliaccio, Raffaella; Neuhaus, John; Miller, Bruce L; Dronkers, Nina F; Brambati, Simona M; Filippi, Massimo; Ogar, Jennifer M; Wilson, Stephen M; Gorno-Tempini, Maria Luisa

    2010-01-01

    Cognitive deficits in semantic dementia have been attributed to anterior temporal lobe grey matter damage; however, key aspects of the syndrome could be due to altered anatomical connectivity between language pathways involving the temporal lobe. The aim of this study was to investigate the left language-related cerebral pathways in semantic dementia using diffusion tensor imaging-based tractography and to combine the findings with cortical anatomical and functional magnetic resonance imaging data obtained during a reading activation task. The left inferior longitudinal fasciculus, arcuate fasciculus and fronto-parietal superior longitudinal fasciculus were tracked in five semantic dementia patients and eight healthy controls. The left uncinate fasciculus and the genu and splenium of the corpus callosum were also obtained for comparison with previous studies. From each tract, mean diffusivity, fractional anisotropy, as well as parallel and transverse diffusivities were obtained. Diffusion tensor imaging results were related to grey and white matter atrophy volume assessed by voxel-based morphometry and functional magnetic resonance imaging activations during a reading task. Semantic dementia patients had significantly higher mean diffusivity, parallel and transverse in the inferior longitudinal fasciculus. The arcuate and uncinate fasciculi demonstrated significantly higher mean diffusivity, parallel and transverse and significantly lower fractional anisotropy. The fronto-parietal superior longitudinal fasciculus was relatively spared, with a significant difference observed for transverse diffusivity and fractional anisotropy, only. In the corpus callosum, the genu showed lower fractional anisotropy compared with controls, while no difference was found in the splenium. The left parietal cortex did not show significant volume changes on voxel-based morphometry and demonstrated normal functional magnetic resonance imaging activation in response to reading items that

  1. Language networks in semantic dementia

    PubMed Central

    Agosta, Federica; Henry, Roland G.; Migliaccio, Raffaella; Neuhaus, John; Miller, Bruce L.; Dronkers, Nina F.; Brambati, Simona M.; Filippi, Massimo; Ogar, Jennifer M.; Wilson, Stephen M.

    2010-01-01

    Cognitive deficits in semantic dementia have been attributed to anterior temporal lobe grey matter damage; however, key aspects of the syndrome could be due to altered anatomical connectivity between language pathways involving the temporal lobe. The aim of this study was to investigate the left language-related cerebral pathways in semantic dementia using diffusion tensor imaging-based tractography and to combine the findings with cortical anatomical and functional magnetic resonance imaging data obtained during a reading activation task. The left inferior longitudinal fasciculus, arcuate fasciculus and fronto-parietal superior longitudinal fasciculus were tracked in five semantic dementia patients and eight healthy controls. The left uncinate fasciculus and the genu and splenium of the corpus callosum were also obtained for comparison with previous studies. From each tract, mean diffusivity, fractional anisotropy, as well as parallel and transverse diffusivities were obtained. Diffusion tensor imaging results were related to grey and white matter atrophy volume assessed by voxel-based morphometry and functional magnetic resonance imaging activations during a reading task. Semantic dementia patients had significantly higher mean diffusivity, parallel and transverse in the inferior longitudinal fasciculus. The arcuate and uncinate fasciculi demonstrated significantly higher mean diffusivity, parallel and transverse and significantly lower fractional anisotropy. The fronto-parietal superior longitudinal fasciculus was relatively spared, with a significant difference observed for transverse diffusivity and fractional anisotropy, only. In the corpus callosum, the genu showed lower fractional anisotropy compared with controls, while no difference was found in the splenium. The left parietal cortex did not show significant volume changes on voxel-based morphometry and demonstrated normal functional magnetic resonance imaging activation in response to reading items that

  2. Abstraction and natural language semantics.

    PubMed Central

    Kayser, Daniel

    2003-01-01

    According to the traditional view, a word prototypically denotes a class of objects sharing similar features, i.e. it results from an abstraction based on the detection of common properties in perceived entities. I explore here another idea: words result from abstraction of common premises in the rules governing our actions. I first argue that taking 'inference', instead of 'reference', as the basic issue in semantics does matter. I then discuss two phenomena that are, in my opinion, particularly difficult to analyse within the scope of traditional semantic theories: systematic polysemy and plurals. I conclude by a discussion of my approach, and by a summary of its main features. PMID:12903662

  3. Did I say dog or cat? A study of semantic error detection and correction in children.

    PubMed

    Hanley, J Richard; Cortis, Cathleen; Budd, Mary-Jane; Nozari, Nazbanou

    2016-02-01

    Although naturalistic studies of spontaneous speech suggest that young children can monitor their speech, the mechanisms for detection and correction of speech errors in children are not well understood. In particular, there is little research on monitoring semantic errors in this population. This study provides a systematic investigation of detection and correction of semantic errors in children between the ages of 5 and 8years as they produced sentences to describe simple visual events involving nine highly familiar animals (the moving animals task). Results showed that older children made fewer errors and corrected a larger proportion of the errors that they made than younger children. We then tested the prediction of a production-based account of error monitoring that the strength of the language production system, and specifically its semantic-lexical component, should be correlated with the ability to detect and repair semantic errors. Strength of semantic-lexical mapping, as well as lexical-phonological mapping, was estimated individually for children by fitting their error patterns, obtained from an independent picture-naming task, to a computational model of language production. Children's picture-naming performance was predictive of their ability to monitor their semantic errors above and beyond age. This relationship was specific to the strength of the semantic-lexical part of the system, as predicted by the production-based monitor.

  4. Examining Lateralized Semantic Access Using Pictures

    ERIC Educational Resources Information Center

    Lovseth, Kyle; Atchley, Ruth Ann

    2010-01-01

    A divided visual field (DVF) experiment examined the semantic processing strategies employed by the cerebral hemispheres to determine if strategies observed with written word stimuli generalize to other media for communicating semantic information. We employed picture stimuli and vary the degree of semantic relatedness between the picture pairs.…

  5. Semantic Relatedness for Evaluation of Course Equivalencies

    ERIC Educational Resources Information Center

    Yang, Beibei

    2012-01-01

    Semantic relatedness, or its inverse, semantic distance, measures the degree of closeness between two pieces of text determined by their meaning. Related work typically measures semantics based on a sparse knowledge base such as WordNet or Cyc that requires intensive manual efforts to build and maintain. Other work is based on a corpus such as the…

  6. Semantic Weight and Verb Retrieval in Aphasia

    ERIC Educational Resources Information Center

    Barde, Laura H. F.; Schwartz, Myrna F.; Boronat, Consuelo B.

    2006-01-01

    Individuals with agrammatic aphasia may have difficulty with verb production in comparison to nouns. Additionally, they may have greater difficulty producing verbs that have fewer semantic components (i.e., are semantically "light") compared to verbs that have greater semantic weight. A connectionist verb-production model proposed by Gordon and…

  7. Chinese Character Decoding: A Semantic Bias?

    ERIC Educational Resources Information Center

    Williams, Clay; Bever, Thomas

    2010-01-01

    The effects of semantic and phonetic radicals on Chinese character decoding were examined. Our results suggest that semantic and phonetic radicals are each available for access when a corresponding task emphasizes one or the other kind of radical. But in a more neutral lexical recognition task, the semantic radical is more informative. Semantic…

  8. Metasemantics: On the Limits of Semantic Theory

    ERIC Educational Resources Information Center

    Parent, T.

    2009-01-01

    METASEMANTICS is a wake-up call for semantic theory: It reveals that some semantic questions have no adequate answer. (This is meant to be the "epistemic" point that certain semantic questions cannot be "settled"--not a metaphysical point about whether there is a fact-of-the-matter.) METASEMANTICS thus checks our default "optimism" that any…

  9. Grafted Subventricular Zone Neural Stem Cells Display Robust Engraftment and Similar Differentiation Properties and Form New Neurogenic Niches in the Young and Aged Hippocampus

    PubMed Central

    Hattiangady, Bharathi

    2016-01-01

    As clinical application of neural stem cell (NSC) grafting into the brain would also encompass aged people, critical evaluation of engraftment of NSC graft-derived cells in the aged hippocampus has significance. We examined the engraftment and differentiation of alkaline phosphatase-positive NSCs expanded from the postnatal subventricular zone (SVZ), 3 months after grafting into the intact young or aged rat hippocampus. Graft-derived cells engrafted robustly into both young and aged hippocampi. Although most graft-derived cells pervasively migrated into different hippocampal layers, the graft cores endured and contained graft-derived neurons expressing neuron-specific nuclear antigen (NeuN) and γ-amino butyric acid in both groups. A fraction of migrated graft-derived cells in the neurogenic subgranular zone-granule cell layer also expressed NeuN. Neuronal differentiation was, however, occasionally seen amid graft-derived cells that had migrated into non-neurogenic regions, where substantial fractions differentiated into S-100β+ astrocytes, NG2+ oligodendrocyte progenitors, or Olig2+ putative oligodendrocytes. In both age groups, graft cores located in non-neurogenic regions displayed many doublecortin-positive (DCX+) immature neurons at 3 months after grafting. Analyses of cells within graft cores using birth dating and putative NSC markers revealed that DCX+ neurons were newly born neurons derived from engrafted cells and that putative NSCs persisted within the graft cores. Thus, both young and aged hippocampi support robust engraftment and similar differentiation of SVZ-NSC graft-derived cells. Furthermore, some grafted NSCs retain the “stemness” feature and produce new neurons even at 3 months after grafting, implying that grafting of SVZ-NSCs into the young or aged hippocampus leads to establishment of new neurogenic niches in non-neurogenic regions. Significance The results demonstrate that advanced age of the host at the time of grafting has no major

  10. The neural basis of surface dyslexia in semantic dementia.

    PubMed

    Wilson, Stephen M; Brambati, Simona M; Henry, Roland G; Handwerker, Daniel A; Agosta, Federica; Miller, Bruce L; Wilkins, David P; Ogar, Jennifer M; Gorno-Tempini, Maria Luisa

    2009-01-01

    Semantic dementia (SD) is a neurodegenerative disease characterized by atrophy of anterior temporal regions and progressive loss of semantic memory. SD patients often present with surface dyslexia, a relatively selective impairment in reading low-frequency words with exceptional or atypical spelling-to-sound correspondences. Exception words are typically 'over-regularized' in SD and pronounced as they are spelled (e.g. 'sew' is pronounced as 'sue'). This suggests that in the absence of sufficient item-specific knowledge, exception words are read by relying mainly on subword processes for regular mapping of orthography to phonology. In this study, we investigated the functional anatomy of surface dyslexia in SD using functional magnetic resonance imaging (fMRI) and studied its relationship to structural damage with voxel-based morphometry (VBM). Five SD patients and nine healthy age-matched controls were scanned while they read regular words, exception words and pseudowords in an event-related design. Vocal responses were recorded and revealed that all patients were impaired in reading low-frequency exception words, and made frequent over-regularization errors. Consistent with prior studies, fMRI data revealed that both groups activated a similar basic network of bilateral occipital, motor and premotor regions for reading single words. VBM showed that these regions were not significantly atrophied in SD. In control subjects, a region in the left intraparietal sulcus was activated for reading pseudowords and low-frequency regular words but not exception words, suggesting a role for this area in subword mapping from orthographic to phonological representations. In SD patients only, this inferior parietal region, which was not atrophied, was also activated by reading low-frequency exception words, especially on trials where over-regularization errors occurred. These results suggest that the left intraparietal sulcus is involved in subword reading processes that are

  11. Distinct loci of lexical and semantic access deficits in aphasia: Evidence from voxel-based lesion-symptom mapping and diffusion tensor imaging.

    PubMed

    Harvey, Denise Y; Schnur, Tatiana T

    2015-06-01

    comprehension. These neuroanatomical-behavioral findings have implications for models of the lexical-semantic language network by demonstrating that semantic interference in language production and comprehension involves different representations which differentially recruit a cognitive control mechanism for interference resolution.

  12. Frontal Lobe Damage Impairs Process and Content in Semantic Memory: Evidence from Category Specific Effects in Progressive Nonfluent Aphasia

    PubMed Central

    Reilly, Jamie; Rodriguez, Amy D.; Peelle, Jonathan E.; Grossman, Murray

    2010-01-01

    Portions of left inferior frontal cortex have been linked to semantic memory both in terms of the content of conceptual representation (e.g., motor aspects in an embodied semantics framework) and the cognitive processes used to access these representations (e.g., response selection). Progressive Nonfluent Aphasia (PNFA) is a neurodegenerative condition characterized by progressive atrophy of left inferior frontal cortex. PNFA can, therefore, provide a lesion model for examining the impact of frontal lobe damage on semantic processing and content. In the current study we examined picture naming in a cohort of PNFA patients across a variety of semantic categories. An embodied approach to semantic memory holds that sensorimotor features such as self-initiated action may assume differential importance for the representation of manufactured artifacts (e.g., naming hand tools). Embodiment theories might therefore predict that patients with frontal damage would be differentially impaired on manufactured artifacts relative to natural kinds, and this prediction was borne out. We also examined patterns of naming errors across a wide range of semantic categories and found that naming error distributions were heterogeneous. Although PNFA patients performed worse overall on naming manufactured artifacts, there was no reliable relationship between anomia and manipulability across semantic categories. These results add to a growing body of research arguing against a purely sensorimotor account of semantic memory, suggesting instead a more nuanced balance of process and content in how the brain represents conceptual knowledge. PMID:20576258

  13. Prolactin induces tuberoinfundibular dopaminergic neurone differentiation in Snell dwarf mice if administered beginning at 3 days of age.

    PubMed

    Khodr, C E; Hurley, D L; Phelps, C J

    2009-06-01

    The hypothalamic tuberoinfundibular dopaminergic (TIDA) neurones secrete dopamine, which inhibits prolactin secretion. TIDA neurone numbers are deficient in Ames (df/df) and Snell (dw/dw) dwarf mice, which lack prolactin, growth hormone and thyroid-stimulating hormone. Prolactin therapy initiated before 21 days maintains normal-sized TIDA neurone numbers in df/df mice and, when initiated as early as 7 days, maintains the maximum TIDA neurone numbers observed in dw/dw development, which are decreased compared to those in normal mice. The present study investigated the effect of prolactin dose and species on TIDA neurone development. Snell dwarf and normal mice were treated with saline, 5 microg of ovine prolactin (oPRL), 50 microg of oPRL, or 50 microg of recombinant mouse prolactin (rmPRL) beginning at 3 days of age. Brains were analysed at 45 days using catecholamine histofluorescence, and immunohistochemistry for tyrosine hydroxylase or bromodeoxyuridine. Normal mice had greater (P

  14. A test of the differential accuracy of the maxillary versus the mandibular dentition in age estimations of immature skeletal remains based on developing tooth length.

    PubMed

    Cardoso, Hugo F V

    2007-03-01

    Liversidge and colleagues developed a method for predicting the age of immature skeletal remains based on the length of developing teeth. This quantitative method combines dental data from both jaws, except for the permanent lateral incisor, and because there are reasons to suspect that these two types of data are not identical and should not be combined, it raises concerns regarding the accuracy of the technique when applied differently to each jaw. In this study, the differential accuracy of the method was test when applied to the maxillary and mandibular dentition. The test sample is comprised of 57 Portuguese subadult skeletons of known age at death. Results suggest an overall high consistency between estimates obtained from both jaws, but for the permanent dentition only. In the deciduous dentition the age estimates obtained from the maxillary teeth tend to be greater than the age estimates obtained from the mandibular pair, and the differences are significant for the incisors and canine. Additionally, ages obtained from the maxillary deciduous canine also differ significantly from true chronological age. In the permanent dentition there were no differences between the ages provided by both jaws but both the maxillary and mandibular second molars show a significant tendency to underestimate true chronological age. Although this study cannot validate completely the method presented by Liversidge and colleagues, it does provide an important test to its accuracy and calls for further research into its overall performance, particularly with respect to the results obtained from both jaws.

  15. Early age decline in DNA repair capacity in the liver: in depth profile of differential gene expression

    PubMed Central

    Guedj, Avital; Geiger-Maor, Anat; Galun, Eithan; Amsalem, Hagai; Rachmilewitz, Jacob

    2016-01-01

    Aging is associated with progressive decline in cell function and with increased damage to macromolecular components. DNA damage, in the form of double-strand breaks (DSBs), increases with age and in turn, contributes to the aging process and age-related diseases. DNA strand breaks triggers a set of highly orchestrated signaling events known as the DNA damage response (DDR), which coordinates DNA repair. However, whether the accumulation of DNA damage with age is a result of decreased repair capacity, remains to be determined. In our study we showed that with age there is a decline in the resolution of foci containing γH2AX and pKAP-1 in diethylnitrosamine (DEN)-treated mouse livers, already evident at a remarkably early age of 6-months. Considerable age-dependent differences in global gene expression profiles in mice livers after exposure to DEN, further affirmed these age related differences in the response to DNA damage. Functional analysis identified p53 as the most overrepresented pathway that is specifically enhanced and prolonged in 6-month-old mice. Collectively, our results demonstrated an early decline in DNA damage repair that precedes ‘old age’, suggesting this may be a driving force contributing to the aging process rather than a phenotypic consequence of old age. PMID:27922819

  16. Differential changes and interactions of autonomic functioning and sleep architecture before and after 50 years of age.

    PubMed

    Kuo, T B J; Li, Jia-Yi; Kuo, Hsu-Ko; Chern, Chang-Ming; Yang, C C H

    2016-02-01

    We hypothesize that the time when age-related changes in autonomic functioning and in sleep structure occur are different and that autonomic functioning modulates sleep architecture differently before and after 50 years of age. Sixty-eight healthy subjects (aged 20 to 79 years old, 49 of them women) were enrolled. Correlation analysis revealed that wake after sleep onset, the absolute and relative value of stage 1 (S1; S1%), and relative value of stage 2 (S2) were positively correlated with age; however, sleep efficiency, stage 3 (S3), S3%, and rapid-eye-movement latency (REML) were negatively correlated with age. Significant degenerations of sleep during normal aging were occurred after 50 years of age; however, significant declines of autonomic activity were showed before 50 years of age. Before 50 years of age, vagal function during sleep was negatively correlated with arousal index; however, after 50 years of age, it was positively correlated with S1 and S1%. In addition, sympathetic activity during wake stage was positively related to S2% only after 50 years of age. Our results imply that the age-related changes in autonomic functioning decline promptly as individuals leave the younger part of their adult life span and that age-related changes in sleep slowly develop as individuals enter the older part of their adult life span. Furthermore, while various aspects of sleep architecture are modulated by both the sympathetic and vagal nervous systems during adult life span, the sleep quality is mainly correlated with the sympathetic division after 50 years of age.

  17. Action representation: crosstalk between semantics and pragmatics.

    PubMed

    Prinz, Wolfgang

    2014-03-01

    Marc Jeannerod pioneered a representational approach to movement and action. In his approach, motor representations provide both, declarative knowledge about action and procedural knowledge for action (action semantics and action pragmatics, respectively). Recent evidence from language comprehension and action simulation supports the claim that action pragmatics and action semantics draw on common representational resources, thus challenging the traditional divide between declarative and procedural action knowledge. To account for these observations, three kinds of theoretical frameworks are discussed: (i) semantics is grounded in pragmatics, (ii) pragmatics is anchored in semantics, and (iii) pragmatics is part and parcel of semantics.

  18. Semantic Annotation of Computational Components

    NASA Technical Reports Server (NTRS)

    Vanderbilt, Peter; Mehrotra, Piyush

    2004-01-01

    This paper describes a methodology to specify machine-processable semantic descriptions of computational components to enable them to be shared and reused. A particular focus of this scheme is to enable automatic compositon of such components into simple work-flows.

  19. Semantic Borders and Incomplete Understanding.

    PubMed

    Silva-Filho, Waldomiro J; Dazzani, Maria Virgínia

    2016-03-01

    In this article, we explore a fundamental issue of Cultural Psychology, that is our "capacity to make meaning", by investigating a thesis from contemporary philosophical semantics, namely, that there is a decisive relationship between language and rationality. Many philosophers think that for a person to be described as a rational agent he must understand the semantic content and meaning of the words he uses to express his intentional mental states, e.g., his beliefs and thoughts. Our argument seeks to investigate the thesis developed by Tyler Burge, according to which our mastery or understanding of the semantic content of the terms which form our beliefs and thoughts is an "incomplete understanding". To do this, we discuss, on the one hand, the general lines of anti-individualism or semantic externalism and, on the other, criticisms of the Burgean notion of incomplete understanding - one radical and the other moderate. We defend our understanding that the content of our beliefs must be described in the light of the limits and natural contingencies of our cognitive capacities and the normative nature of our rationality. At heart, anti-individualism leads us to think about the fact that we are social creatures, living in contingent situations, with important, but limited, cognitive capacities, and that we receive the main, and most important, portion of our knowledge simply from what others tell us. Finally, we conclude that this discussion may contribute to the current debate about the notion of borders.

  20. Incrementally Dissociating Syntax and Semantics

    ERIC Educational Resources Information Center

    Brennan, Jonathan R.

    2010-01-01

    A basic challenge for research into the neurobiology of language is understanding how the brain combines words to make complex representations. Linguistic theory divides this task into several computations including syntactic structure building and semantic composition. The close relationship between these computations, however, poses a strong…

  1. Genres, Semantics, and Classroom Education.

    ERIC Educational Resources Information Center

    Lemke, Jay

    1988-01-01

    Argues that competence in academic subjects depends on mastery of their specialized patterns of language use. These patterns are described in terms of: 1) the semantics underlying Halliday's functional linguistics and 2) the structural analysis of communication genres. A sample classroom episode illustrates relationships among semantic…

  2. A Note on Semantic Selection.

    ERIC Educational Resources Information Center

    Endo, Yoshio

    1989-01-01

    The notions of categorical selection (c-selection) and semantic selection (s-selection) as outlined in recent research on generative grammar are discussed. The first section addresses the type of selectional constraint imposed on English small clauses (e.g., "John considers [Mary smart]"). In the second section, it is suggested that the constraint…

  3. Taxonomic and Thematic Semantic Systems.

    PubMed

    Mirman, Daniel; Landrigan, Jon-Frederick; Britt, Allison E

    2017-03-23

    Object concepts are critical for nearly all aspects of human cognition, from perception tasks like object recognition, to understanding and producing language, to making meaningful actions. Concepts can have 2 very different kinds of relations: similarity relations based on shared features (e.g., dog-bear), which are called "taxonomic" relations, and contiguity relations based on co-occurrence in events or scenarios (e.g., dog-leash), which are called "thematic" relations. Here, we report a systematic review of experimental psychology and cognitive neuroscience evidence of this distinction in the structure of semantic memory. We propose 2 principles that may drive the development of distinct taxonomic and thematic semantic systems: differences between which features determine taxonomic versus thematic relations, and differences in the processing required to extract taxonomic versus thematic relations. This review brings together distinct threads of behavioral, computational, and neuroscience research on semantic memory in support of a functional and neural dissociation, and defines a framework for future studies of semantic memory. (PsycINFO Database Record

  4. Semantic Fission through Dialect Fusion.

    ERIC Educational Resources Information Center

    Linn, Michael D.

    The linguistic atlas projects have provided much information on the regional distribution of pronunciation, vocabulary, and syntax and have given important evidence for a greater understanding of problems involved in semantic change, particularly in pointing out transition areas where dialects become fused. In a study supplementary to that…

  5. The Semantic Web in Education

    ERIC Educational Resources Information Center

    Ohler, Jason

    2008-01-01

    The semantic web or Web 3.0 makes information more meaningful to people by making it more understandable to machines. In this article, the author examines the implications of Web 3.0 for education. The author considers three areas of impact: knowledge construction, personal learning network maintenance, and personal educational administration.…

  6. Colourful Semantics: A Clinical Investigation

    ERIC Educational Resources Information Center

    Bolderson, Sarah; Dosanjh, Christine; Milligan, Claudine; Pring, Tim; Chiat, Shula

    2011-01-01

    Children with language difficulties often omit verbs and grammatical elements and fail to complete sentences. Bryan (1997) described "colourful semantics", a therapy she used to treat a 5-year-old boy. The therapy uses colour coding to highlight the predicate argument structure of sentences. This study further tested the therapy's…

  7. Semantic Preview Benefit during Reading

    ERIC Educational Resources Information Center

    Hohenstein, Sven; Kliegl, Reinhold

    2014-01-01

    Word features in parafoveal vision influence eye movements during reading. The question of whether readers extract semantic information from parafoveal words was studied in 3 experiments by using a gaze-contingent display change technique. Subjects read German sentences containing 1 of several preview words that were replaced by a target word…

  8. Changes in Search Path Complexity and Length During Learning of a Virtual Water Maze: Age Differences and Differential Associations with Hippocampal Subfield Volumes.

    PubMed

    Daugherty, Ana M; Bender, Andrew R; Yuan, Peng; Raz, Naftali

    2016-06-01

    Impairment of hippocampus-dependent cognitive processes has been proposed to underlie age-related deficits in navigation. Animal studies suggest a differential role of hippocampal subfields in various aspects of navigation, but that hypothesis has not been tested in humans. In this study, we examined the association between volume of hippocampal subfields and age differences in virtual spatial navigation. In a sample of 65 healthy adults (age 19-75 years), advanced age was associated with a slower rate of improvement operationalized as shortening of the search path over 25 learning trials on a virtual Morris water maze task. The deficits were partially explained by greater complexity of older adults' search paths. Larger subiculum and entorhinal cortex volumes were associated with a faster decrease in search path complexity, which in turn explained faster shortening of search distance. Larger Cornu Ammonis (CA)1-2 volume was associated with faster distance shortening, but not in path complexity reduction. Age differences in regional volumes collectively accounted for 23% of the age-related variance in navigation learning. Independent of subfield volumes, advanced age was associated with poorer performance across all trials, even after reaching the asymptote. Thus, subiculum and CA1-2 volumes were associated with speed of acquisition, but not magnitude of gains in virtual maze navigation.

  9. Differential age- and disease-related effects on the expression of genes related to the arachidonic acid signaling pathway in schizophrenia.

    PubMed

    Tang, Bin; Capitao, Cristina; Dean, Brian; Thomas, Elizabeth A

    2012-04-30

    We have previously identified differential effects of age on global brain gene expression profiles in subjects with schizophrenia compared to normal controls. Here, we have focused on age-related effects of genes associated with the arachidonic acid-related inflammation pathway. Linear correlation analysis of published microarray expression data reveal strong age- and cell-type- specific-effects on the expression of genes related to the arachidonic acid signaling pathway, which differed in control subjects compared to those with schizophrenia. Using real-time qPCR analysis, we validated age and disease effects of arachidonic acid-related genes in a large cohort of subjects with schizophrenia and matched controls (n=76 subjects in total). We found that levels of prostaglandin-endoperoxide synthase 1 (PTGS1; aka COX-1) and prostaglandin-endoperoxide receptor 3 (PTGER3) mRNA are increased, and levels of prostaglandin-endoperoxide synthase 2 (PTGS2; aka COX-2) mRNA are decreased, in older subjects with schizophrenia (> 40years of age) compared to matched normal controls or younger subjects with schizophrenia (< 40years of age). These findings contribute to the accumulating evidence suggesting that inflammatory processes in the CNS contribute to pathophysiology of schizophrenia and further suggest that age may be an important factor in the potential use of anti-inflammatory therapies.

  10. Age and gender differential relationship between employment status and body mass index among middle-aged and elderly adults: a cross-sectional study

    PubMed Central

    Noh, Jin-Won; Kim, Jinseok; Park, Jumin; Oh, In-Hwan; Kwon, Young Dae

    2016-01-01

    Objective To determine the influence of age and gender, respectively, on the association between employment status and body mass index (BMI) in Korean adults using a large, nationally representative sample. Design Cross-sectional study. Setting South Korea. Participants 7228 from fourth wave of the Korean Longitudinal Study of Aging (KLoSA), the survey's short form and year: ‘KLoSA 2012’. Main outcome measures BMI. Results BMI among the employed was higher than among the unemployed for those under 60. In terms of gender, employed men reported higher BMI than their unemployed counterparts, whereas employed women reported lower BMI than did unemployed women. Conclusions Employment status showed varying impacts on obesity by age and gender. Both unemployment at or after 60, as well as unemployment among women, is associated with increased BMI compared with unemployment among younger individuals or men, respectively. PMID:27852710

  11. An Experiment in Scientific Code Semantic Analysis

    NASA Technical Reports Server (NTRS)

    Stewart, Mark E. M.

    1998-01-01

    This paper concerns a procedure that analyzes aspects of the meaning or semantics of scientific and engineering code. This procedure involves taking a user's existing code, adding semantic declarations for some primitive variables, and parsing this annotated code using multiple, distributed expert parsers. These semantic parser are designed to recognize formulae in different disciplines including physical and mathematical formulae and geometrical position in a numerical scheme. The parsers will automatically recognize and document some static, semantic concepts and locate some program semantic errors. Results are shown for a subroutine test case and a collection of combustion code routines. This ability to locate some semantic errors and document semantic concepts in scientific and engineering code should reduce the time, risk, and effort of developing and using these codes.

  12. Age influences TSH serum levels after withdrawal of l-thyroxine or rhTSH stimulation in patients affected by differentiated thyroid cancer.

    PubMed

    Montesano, Teresa; Durante, Cosimo; Attard, Marco; Crocetti, Umberto; Meringolo, Domenico; Bruno, Rocco; Tumino, Salvatore; Rubello, Domenico; Al-Nahhas, Adil; Colandrea, Marzia; Maranghi, Marianna; Travascio, Laura; Ronga, Giuseppe; Torlontano, Massimo

    2007-09-01

    Recombinant human TSH (rhTSH) has been recently suggested for radioiodine ablation in patients with differentiated thyroid cancer (DTC). To date, studies are still not available about the effectiveness of rhTSH stimulation depending on the age, since serum TSH clearance may be different in younger and in older patients. The aim of this study was to investigate the influence of age to serum TSH levels after rhTSH stimulation and thyroid hormone withdrawal (THW). We retrospectively evaluated two groups of consecutive DTC patients: group 1 (311 patients, age 49.0+/-13.6 years, ranging 15-86) underwent rhTSH stimulation 6-12 months after thyroid ablation (rhTSH-group); group 2 (84 patients, age 46.9+/-13.5 years, ranging 20-77) was followed by THW (THW-group). The influence of age, gender, body mass index and body surface area to serum TSH levels were evaluated in both groups. RhTSH-group: on day 5 (d5), TSH levels were 32.7+/-21.4 microU/ml (range 0.8-136.6). By univariate analysis, d5-TSH was positively related to age (r=0.27, p=0.0001) and no correlations were found with the other parameters. At multivariate analysis, both age and gender (female) were independently associated with d5-TSH levels. THW-group: after thyroid hormone withdrawal, TSH levels were 71.1+/-36.4 microU/ml (range 8.5-200). At univariate analysis, only age was significantly and negatively related to serum TSH levels (r=-0.31, p=0.004). Our data indicate that age and gender seem to positively influence serum TSH levels after rhTSH stimulation. An opposite effect of age on serum TSH levels has been observed after THW. Therapeutic implications ((131)I-treatment) of these findings have to be better investigated in prospective studies.

  13. Language of the aging brain: Event-related potential studies of comprehension in older adults

    PubMed Central

    Wlotko, Edward W.; Lee, Chia-Lin; Federmeier, Kara D.

    2010-01-01

    Normal aging brings increased richness in knowledge and experience as well as declines in cognitive abilities. Event-related brain potential (ERP) studies of language comprehension corroborate findings showing that the structure and organization of semantic knowledge remains relatively stable with age. Highlighting the advantages of the temporal and functional specificity of ERPs, this survey focuses on age-related changes in higher-level processes required for the successful comprehension of meaning representations built from multiple words. Older adults rely on different neural pathways and cognitive processes during normal, everyday comprehension, including a shift away from the predictive use of sentential context, differential recruitment of neural resources, and reduced engagement of controlled processing. Within age groups, however, there are important individual differences that, for example, differentiate a subset of older adults whose processing patterns more closely resemble that of young adults, providing a window into cognitive skills and abilities that may mediate or moderate age-related declines. PMID:20823949

  14. Category-specific semantic deficits in Alzheimer's disease: a semantic priming study.

    PubMed

    Hernández, Mireia; Costa, Albert; Juncadella, Montserrat; Sebastián-Gallés, Núria; Reñé, Ramón

    2008-03-07

    Category-specific semantic deficits in individuals suffering brain damage after relatively focal lesions provide an important source of evidence about the organization of semantic knowledge. However, whether Alzheimer's disease (AD), in which the brain damage is more widespread, affects semantic categories to a different extent is still controversial. In the present study, we assess this issue by means of the semantic priming technique. AD patients with a mild impairment of their semantic knowledge showed comparable priming effects to that of controls for the categories of animals and artifacts. Interestingly, however, patients with a moderate impairment of their semantic knowledge showed a normal priming effect for animals but a very reduced priming effect (if any) for artifacts. These results reveal that AD may affect the semantic knowledge of different semantic categories to a different extent. The implications of this observation for current theoretical accounts of semantic representation in the brain are discussed.

  15. Semantic facilitation in bilingual first language acquisition.

    PubMed

    Bilson, Samuel; Yoshida, Hanako; Tran, Crystal D; Woods, Elizabeth A; Hills, Thomas T

    2015-07-01

    Bilingual first language learners face unique challenges that may influence the rate and order of early word learning relative to monolinguals. A comparison of the productive vocabularies of 435 children between the ages of 6 months and 7 years-181 of which were bilingual English learners-found that monolinguals learned both English words and all-language concepts faster than bilinguals. However, bilinguals showed an enhancement of an effect previously found in monolinguals-the preference for learning words with more associative cues. Though both monolinguals and bilinguals were best fit by a similar model of word learning, semantic network structure and growth indicated that the two groups were learning English words in a different order. Further, in comparison with a model of two-monolinguals-in-one-mind, bilinguals overproduced translational equivalents. Our results support an emergent account of bilingual first language acquisition, where learning a word in one language facilitates its acquisition in a second language.

  16. Is Age Kinder to the Initially More Able? Differential Ageing of Verbal Ability in the Healthy Old People in Edinburgh Study.

    ERIC Educational Resources Information Center

    Deary, Ian; MacLennan, William J.; Starr, John M.

    1998-01-01

    Results from a study of 387 healthy old people studied at baseline and four years later in Edinburgh (Scotland) suggest that, those with higher baseline ability, in higher social-class groups, with more education, and those who are younger are relatively protected from a decline in verbal intelligence, measured by an adult reading test, with age.…

  17. Differential susceptibility of interneurons expressing neuropeptide Y or parvalbumin in the aged hippocampus to acute seizure activity.

    PubMed

    Kuruba, Ramkumar; Hattiangady, Bharathi; Parihar, Vipan K; Shuai, Bing; Shetty, Ashok K

    2011-01-01

    Acute seizure (AS) activity in old age has an increased predisposition for evolving into temporal lobe epilepsy (TLE). Furthermore, spontaneous seizures and cognitive dysfunction after AS activity are often intense in the aged population than in young adults. This could be due to an increased vulnerability of inhibitory interneurons in the aged hippocampus to AS activity. We investigated this issue by comparing the survival of hippocampal GABA-ergic interneurons that contain the neuropeptide Y (NPY) or the calcium binding protein parvalbumin (PV) between young adult (5-months old) and aged (22-months old) F344 rats at 12 days after three-hours of AS activity. Graded intraperitoneal injections of the kainic acid (KA) induced AS activity and a diazepam injection at 3 hours after the onset terminated AS-activity. Measurement of interneuron numbers in different hippocampal subfields revealed that NPY+ interneurons were relatively resistant to AS activity in the aged hippocampus in comparison to the young adult hippocampus. Whereas, PV+ interneurons were highly susceptible to AS activity in both age groups. However, as aging alone substantially depleted these populations, the aged hippocampus after three-hours of AS activity exhibited 48% reductions in NPY+ interneurons and 70% reductions in PV+ interneurons, in comparison to the young hippocampus after similar AS activity. Thus, AS activity-induced TLE in old age is associated with far fewer hippocampal NPY+ and PV+ interneuron numbers than AS-induced TLE in the young adult age. This discrepancy likely underlies the severe spontaneous seizures and cognitive dysfunction observed in the aged people after AS activity.

  18. Age effects on associative memory for novel picture pairings.

    PubMed

    Bridger, Emma K; Kursawe, Anna-Lena; Bader, Regine; Tibon, Roni; Gronau, Nurit; Levy, Daniel A; Mecklinger, Axel

    2017-04-01

    Normal aging is usually accompanied by greater memory decline for associations than for single items. Though associative memory is generally supported by recollection, it has been suggested that familiarity can also contribute to associative memory when stimuli can be unitized and encoded as a single entity. Given that familiarity remains intact during healthy aging, this may be one route to reducing age-related associative deficits. The current study investigated age-related differences in associative memory under conditions that were expected to differentially promote unitization, in this case by manipulating the spatial arrangement of two semantically unrelated objects positioned relative to each other in either spatially implausible or plausible orientations. Event-related potential (ERP) correlates of item and associative memory were recorded whilst younger and older adults were required to discriminate between old, recombined and new pairs of objects. These ERP correlates of item and associative memory did not vary with plausibility, whereas behavioral measures revealed that both associative and item memory were greater for spatially plausible than implausible pair arrangements. Contrary to predictions, older adults were less able to take advantage of this memory benefit than younger participants. Potential reasons for this are considered, and these are informed by those lines of evidence which indicate older participants were less sensitive to the bottom-up spatial manipulation employed here. It is recommended that future strategies for redressing age-related associative deficits should take account of the aging brain's increasing reliance on pre-existing semantic associations.

  19. Children Use Statistics and Semantics in the Retreat from Overgeneralization

    PubMed Central

    Blything, Ryan P.; Ambridge, Ben; Lieven, Elena V. M.

    2014-01-01

    How do children learn to restrict their productivity and avoid ungrammatical utterances? The present study addresses this question by examining why some verbs are used with un- prefixation (e.g., unwrap) and others are not (e.g., *unsqueeze). Experiment 1 used a priming methodology to examine children's (3–4; 5–6) grammatical restrictions on verbal un- prefixation. To elicit production of un-prefixed verbs, test trials were preceded by a prime sentence, which described reversal actions with grammatical un- prefixed verbs (e.g., Marge folded her arms and then she unfolded them). Children then completed target sentences by describing cartoon reversal actions corresponding to (potentially) un- prefixed verbs. The younger age-group's production probability of verbs in un- form was negatively related to the frequency of the target verb in bare form (e.g., squeez/e/ed/es/ing), while the production probability of verbs in un- form for both age groups was negatively predicted by the frequency of synonyms to a verb's un- form (e.g., release/*unsqueeze). In Experiment 2, the same children rated the grammaticality of all verbs in un- form. The older age-group's grammaticality judgments were (a) positively predicted by the extent to which each verb was semantically consistent with a semantic “cryptotype” of meanings - where “cryptotype” refers to a covert category of overlapping, probabilistic meanings that are difficult to access - hypothesised to be shared by verbs which take un-, and (b) negatively predicted by the frequency of synonyms to a verb's un- form. Taken together, these experiments demonstrate that children as young as 4;0 employ pre-emption and entrenchment to restrict generalizations, and that use of a semantic cryptotype to guide judgments of overgeneralizations is also evident by age 6;0. Thus, even early developmental accounts of children's restriction of productivity must encompass a mechanism in which a verb's semantic and statistical properties

  20. Gender and Age Effects Interact in Preschoolers' Help-Seeking: Evidence for Differential Responses to Changes in Task Difficulty

    ERIC Educational Resources Information Center

    Thompson, R. Bruce; Cothran, Thomas; McCall, Daniel

    2012-01-01

    This study explored preschool age and gender differences in help-seeking within the theoretical framework of scaffolded problem-solving and self-regulation (Bruner, 1986; Rogoff, 1990; Vygotsky, 1978; 1986). Within-subject analyses tracked changes in help-seeking among 62 preschoolers (34 boys, 28 girls, mean age 4.22 years) solving a challenging…

  1. The role of the right hemisphere in semantic control: A case-series comparison of right and left hemisphere stroke

    PubMed Central

    Thompson, Hannah E.; Henshall, Lauren; Jefferies, Elizabeth

    2016-01-01

    Semantic control processes guide conceptual retrieval so that we are able to focus on non-dominant associations and features when these are required for the task or context, yet the neural basis of semantic control is not fully understood. Neuroimaging studies have emphasised the role of left inferior frontal gyrus (IFG) in controlled retrieval, while neuropsychological investigations of semantic control deficits have almost exclusively focussed on patients with left-sided damage (e.g., patients with semantic aphasia, SA). Nevertheless, activation in fMRI during demanding semantic tasks typically extends to right IFG. To investigate the role of the right hemisphere (RH) in semantic control, we compared nine RH stroke patients with 21 left-hemisphere SA patients, 11 mild SA cases and 12 healthy, aged-matched controls on semantic and executive tasks, plus experimental tasks that manipulated semantic control in paradigms particularly sensitive to RH damage. RH patients had executive deficits to parallel SA patients but they performed well on standard semantic tests. Nevertheless, multimodal semantic control deficits were found in experimental tasks involving facial emotions and the ‘summation’ of meaning across multiple items. On these tasks, RH patients showed effects similar to those in SA cases – multimodal deficits that were sensitive to distractor strength and cues and miscues, plus increasingly poor performance in cyclical matching tasks which repeatedly probed the same set of concepts. Thus, despite striking differences in single-item comprehension, evidence presented here suggests semantic control is bilateral, and disruption of this component of semantic cognition can be seen following damage to either hemisphere. PMID:26945505

  2. Exploiting semantic linkages among multiple sources for semantic information retrieval

    NASA Astrophysics Data System (ADS)

    Li, JianQiang; Yang, Ji-Jiang; Liu, Chunchen; Zhao, Yu; Liu, Bo; Shi, Yuliang

    2014-07-01

    The vision of the Semantic Web is to build a global Web of machine-readable data to be consumed by intelligent applications. As the first step to make this vision come true, the initiative of linked open data has fostered many novel applications aimed at improving data accessibility in the public Web. Comparably, the enterprise environment is so different from the public Web that most potentially usable business information originates in an unstructured form (typically in free text), which poses a challenge for the adoption of semantic technologies in the enterprise environment. Considering that the business information in a company is highly specific and centred around a set of commonly used concepts, this paper describes a pilot study to migrate the concept of linked data into the development of a domain-specific application, i.e. the vehicle repair support system. The set of commonly used concepts, including the part name of a car and the phenomenon term on the car repairing, are employed to build the linkage between data and documents distributed among different sources, leading to the fusion of documents and data across source boundaries. Then, we describe the approaches of semantic information retrieval to consume these linkages for value creation for companies. The experiments on two real-world data sets show that the proposed approaches outperform the best baseline 6.3-10.8% and 6.4-11.1% in terms of top five and top 10 precisions, respectively. We believe that our pilot study can serve as an important reference for the development of similar semantic applications in an enterprise environment.

  3. Developmental changes in the neural influence of sublexical information on semantic processing.

    PubMed

    Lee, Shu-Hui; Booth, James R; Chou, Tai-Li

    2015-07-01

    Functional magnetic resonance imaging (fMRI) was used to examine the developmental changes in a group of normally developing children (aged 8-12) and adolescents (aged 13-16) during semantic processing. We manipulated association strength (i.e. a global reading unit) and semantic radical (i.e. a local reading unit) to explore the interaction of lexical and sublexical semantic information in making semantic judgments. In the semantic judgment task, two types of stimuli were used: visually-similar (i.e. shared a semantic radical) versus visually-dissimilar (i.e. did not share a semantic radical) character pairs. Participants were asked to indicate if two Chinese characters, arranged according to association strength, were related in meaning. The results showed greater developmental increases in activation in left angular gyrus (BA 39) in the visually-similar compared to the visually-dissimilar pairs for the strong association. There were also greater age-related increases in angular gyrus for the strong compared to weak association in the visually-similar pairs. Both of these results suggest that shared semantics at the sublexical level facilitates the integration of overlapping features at the lexical level in older children. In addition, there was a larger developmental increase in left posterior middle temporal gyrus (BA 21) for the weak compared to strong association in the visually-dissimilar pairs, suggesting conflicting sublexical information placed greater demands on access to lexical representations in the older children. All together, these results suggest that older children are more sensitive to sublexical information when processing lexical representations.

  4. Higher-Order Factor Structure of the Differential Ability Scales-II: Consistency across Ages 4 to 17

    ERIC Educational Resources Information Center

    Keith, Timothy Z.; Low, Justin A.; Reynolds, Matthew R.; Patel, Puja G.; Ridley, Kristen P.

    2010-01-01

    The recently published second edition of the Differential Abilities Scale (DAS-II) is designed to measure multiple broad and general abilities from Cattell-Horn-Carroll (CHC) theory. Although the technical manual presents information supporting the test's structure, additional research is needed to determine the constructs measured by the test and…

  5. Language-related activations in the left prefrontal regions are differentially modulated by age, proficiency, and task demands.

    PubMed

    Tatsuno, Yoshinori; Sakai, Kuniyoshi L

    2005-02-16

    It remains to be elucidated how cortical activations are modulated by factors of age, proficiency, and language task demands when mastering first language (L1) and a second language (L2). Using functional magnetic resonance imaging, we tested subjects aged 13 (the age 13 group) and 19 (the age 19 group), thereby comparing the cortical activations involved in past-tense verb identification with those involved in verb matching. We found that the activation in the dorsal triangular part of the left inferior frontal gyrus (IFG) was lower, corresponding to a higher proficiency in English (L2) in the older subjects, suggesting that the proficiency level plays a major role in the activation of this region during L2 acquisition. Moreover, the lower activation in the triangular and orbital parts of the left IFG (F3t/F3O) for the irregular past tense corresponding to a higher proficiency in L2, together with the nonsignificant activation for the regular past tense when its performance almost reached perfection for age 19, suggests that the modulation of the left F3t/F3O activation reflects language task demands for identifying correct past-tense forms. On the other hand, the left F3t/F3O activation in Japanese (L1) for age 13 was significantly greater than that for age 19, despite the matched performances in L1. These results suggest that the left IFG subserves language-specific functions that are critically required when mastering any language.

  6. Differential mechanisms of ang (1-7)-mediated vasodepressor effect in adult and aged candesartan-treated rats.

    PubMed

    Bosnyak, S; Widdop, R E; Denton, K M; Jones, E S

    2012-01-01

    Angiotensin (1-7) (Ang (1-7)) causes vasodilator effects in Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs) via angiotensin type 2 receptors (AT(2)R). However, the role of vascular AT(2)R in aging is not known. Therefore, we examined the effect of aging on Ang (1-7)-mediated vasodepressor effects and vascular angiotensin receptor localization in aging. Blood pressure was measured in conscious adult (~17 weeks) and aged (~19 months) normotensive rats that received drug combinations in a randomised fashion over a 4-day protocol: (i) Ang (1-7) alone, (ii) AT(1)R antagonist, candesartan, alone, (iii) Ang (1-7) and candesartan, or (iv) Ang-(1-7), candesartan, and the AT(2)R antagonist, PD123319. In a separate group of animals, the specific MasR antagonist, A779, was administered in place of PD123319. Receptor localisation was also assessed in aortic sections from adult and aged WKY rats by immunofluorescence. Ang (1-7) reduced blood pressure (~15 mmHg) in adult normotensive rats although this effect was dependant on the background dose of candesartan. This depressor effect was reversed by AT(2)R blockade. In aged rats, the depressor effect of Ang (1-7) was evident but was now inhibited by either AT(2)R blockade or MasR blockade. At the same time, AT(2)R, MasR, and ACE2 immunoreactivity was markedly elevated in aortic sections from aged animals. These results indicate that the Ang (1-7)-mediated depressor effect was preserved in aged animals. Whereas Ang (1-7) effects were mediated exclusively via stimulation of AT(2)R in adult WKY, with aging the vasodepressor effect of Ang (1-7) involved both AT(2)R and MasR.

  7. Adopting Abstract Images for Semantic Scene Understanding.

    PubMed

    Zitnick, C Lawrence; Vedantam, Ramakrishna; Parikh, Devi

    2016-04-01

    Relating visual information to its linguistic semantic meaning remains an open and challenging area of research. The semantic meaning of images depends on the presence of objects, their attributes and their relations to other objects. But precisely characterizing this dependence requires extracting complex visual information from an image, which is in general a difficult and yet unsolved problem. In this paper, we propose studying semantic information in abstract images created from collections of clip art. Abstract images provide several advantages over real images. They allow for the direct study of how to infer high-level semantic information, since they remove the reliance on noisy low-level object, attribute and relation detectors, or the tedious hand-labeling of real images. Importantly, abstract images also allow the ability to generate sets of semantically similar scenes. Finding analogous sets of real images that are semantically similar would be nearly impossible. We create 1,002 sets of 10 semantically similar abstract images with corresponding written descriptions. We thoroughly analyze this dataset to discover semantically important features, the relations of words to visual features and methods for measuring semantic similarity. Finally, we study the relation between the saliency and memorability of objects and their semantic importance.

  8. Differential Effects of Delayed Aging on Phenotype and Striatal Pathology in a Murine Model of Huntington Disease

    PubMed Central

    Tallaksen-Greene, Sara J.; Sadagurski, Marianna; Zeng, Li; Mauch, Roseanne; Perkins, Matthew; Banduseela, Varuna C.; Lieberman, Andrew P.; Miller, Richard A.; Paulson, Henry L.

    2014-01-01

    The common neurodegenerative syndromes exhibit age-related incidence, and many Mendelian neurodegenerative diseases exhibit age-related penetrance. Mutations slowing aging retard age related pathologies. To assess whether delayed aging retards the effects of a mutant allele causing a Huntington's disease (HD)-like syndrome, we generated compound mutant mice, placing a dominant HD knock-in polyglutamine allele onto the slow-aging Snell dwarf genotype. The Snell genotype did not affect mutant huntingtin protein expression. Bigenic and control mice were evaluated prospectively from 10 to 100 weeks of age. Adult HD knock-in allele mice lost weight progressively with weight loss blunted significantly in male bigenic HD knock-in/Snell dwarf mice. Impaired balance beam performance developed significantly more slowly in bigenic HD knock-in/Snell dwarf mice. Striatal dopamine receptor expression was diminished significantly and similarly in all HD-like mice, regardless of the Snell genotype. Striatal neuronal intranuclear inclusion burden was similar between HD knock-in mice with and without the Snell genotype, whereas nigral neuropil aggregates were diminished in bigenic HD knock-in/Snell dwarf mice. Compared with control mice, Snell dwarf mice exhibited differences in regional benzodiazepine and cannabinoid receptor binding site expression. These results indicate that delaying aging delayed behavioral decline with little effect on the development of striatal pathology in this model of HD but may have altered synaptic pathology. These results indicate that mutations prolonging lifespan in mice delay onset of significant phenotypic features of this model and also demonstrate dissociation between striatal pathology and a commonly used behavioral measure of disease burden in HD models. PMID:25411494

  9. The evolution of semantic systems.

    PubMed

    Bainbridge, William Sims

    2004-05-01

    Semantic or cultural systems are sets of concepts connected by meaningful relationships, and they exhibit properties similar to those of populations of biological organisms. Drawing upon ideas from evolutionary biology and methods from information technology, this article explores the potential for research and engineering on the evolution of semantic systems. Such work in cultural genetics requires two things: (1) a rigorous but evolving taxonomic system to categorize cultural artifacts, elements, and clusters, and (2) a set of hypotheses about the processes that cause evolutionary change. This article illustrates systematic approaches to cultural taxonomy with data on the popular ideology of the space program, science fiction motion pictures, nanotechnology books, and nanotechnology research grants. It offers hypotheses derived from evolutionary and population biology that might be useful in explaining cultural evolution.

  10. The Formal Semantics of PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Shankar, Natarajan

    1999-01-01

    A specification language is a medium for expressing what is computed rather than how it is computed. Specification languages share some features with programming languages but are also different in several important ways. For our purpose, a specification language is a logic within which the behavior of computational systems can be formalized. Although a specification can be used to simulate the behavior of such systems, we mainly use specifications to state and prove system properties with mechanical assistance. We present the formal semantics of the specification language of SRI's Prototype Verification System (PVS). This specification language is based on the simply typed lambda calculus. The novelty in PVS is that it contains very expressive language features whose static analysis (e.g., typechecking) requires the assistance of a theorem prover. The formal semantics illuminates several of the design considerations underlying PVS, the interaction between theorem proving and typechecking.

  11. Semantic priming of familiar songs.

    PubMed

    Johnson, Sarah K; Halpern, Andrea R

    2012-05-01

    We explored the functional organization of semantic memory for music by comparing priming across familiar songs both within modalities (Experiment 1, tune to tune; Experiment 3, category label to lyrics) and across modalities (Experiment 2, category label to tune; Experiment 4, tune to lyrics). Participants judged whether or not the target tune or lyrics were real (akin to lexical decision tasks). We found significant priming, analogous to linguistic associative-priming effects, in reaction times for related primes as compared to unrelated primes, but primarily for within-modality comparisons. Reaction times to tunes (e.g., "Silent Night") were faster following related tunes ("Deck the Hall") than following unrelated tunes ("God Bless America"). However, a category label (e.g., Christmas) did not prime tunes from within that category. Lyrics were primed by a related category label, but not by a related tune. These results support the conceptual organization of music in semantic memory, but with potentially weaker associations across modalities.

  12. Semantic Event Correlation Using Ontologies

    NASA Astrophysics Data System (ADS)

    Moser, Thomas; Roth, Heinz; Rozsnyai, Szabolcs; Mordinyi, Richard; Biffl, Stefan

    Complex event processing (CEP) is a software architecture paradigm that aims at low latency, high throughput, and quick adaptability of applications for supporting and improving event-driven business processes. Events sensed in real time are the basic information units on which CEP applications operate and react in self-contained decision cycles based on defined processing logic and rules. Event correlation is necessary to relate events gathered from various sources for detecting patterns and situations of interest in the business context. Unfortunately, event correlation has been limited to syntactically identical attribute values instead of addressing semantically equivalent attribute meanings. Semantic equivalence is particularly relevant if events come from organizations that use different terminologies for common concepts.

  13. Differential expression of cytokines in subcutaneous and marrow fat of aging C57BL/6J mice.

    PubMed

    Gasparrini, Marco; Rivas, Daniel; Elbaz, Alexandre; Duque, Gustavo

    2009-09-01

    Increasing marrow adipogenesis plays a causative role in the pathogenesis of age-related bone loss that could be associated with high cytokine production. In this study, we characterized the age-related changes in cytokine expression by bone marrow (BM) adipocytes as compared with subcutaneous (SC) fat. BM and SC adipocytes were isolated from young (4 months) and old (24 months) male C57BL/6J. Total proteins were extracted and proteomic analysis of 96 cytokines was performed using a cytokine antibody array. Proteins showing a significant change were grouped according with their known function in bone. We found a significant age-induced difference in the expression of 53 cytokines. As compared with SC adipocytes, aging BM adipocytes showed a more pro-adipogenic, anti-osteoblastogenic and pro-apoptotic phenotype. These data suggest that, with aging, BM adipocytes become significantly more toxic than SC adipocytes. These cytokines, if secreted, could play a role in the pathogenesis of age-related bone loss by affecting other cells within the marrow milieu.

  14. Heat Stress and Hormetin-Induced Hormesis in Human Cells: Effects on Aging, Wound Healing, Angiogenesis, and Differentiation

    PubMed Central

    Rattan, Suresh I. S.; Fernandes, Ricardo A.; Demirovic, Dino; Dymek, Barbara; Lima, Cristovao F.

    2009-01-01

    Accumulation of molecular damage and increased molecular heterogeneity are hallmarks of cellular aging. Mild stress-induced hormesis can be an effective way for reducing the accumulation of molecular damage, and thus slowing down aging from within. We have shown that repeated mild heat stress (RMHS) has anti-aging effects on growth and various other cellular and biochemical characteristics of normal human skin fibroblasts and keratinocytes undergoing aging in vitro. RMHS given to human cells increased the basal levels of various chaperones, reduced the accumulation of damaged proteins, stimulated proteasomal activities, increased the cellular resistance to other stresses, enhanced the levels of various antioxidant enzymes, enhanced the activity and amounts of sodium-potassium pump, and increased the phosphorylation-mediated activities of various stress kinases. We have now observed novel hormetic effects of mild heat stress on improving the wound healing capacity of skin fibroblasts and on enhancing the angiogenic ability of endothelial cells. We have also tested potential hormetins, such as curcumin and rosmarinic acid in bringing about their beneficial effects in human cells by inducing stress response pathways involving heat shock proteins and hemeoxygenase HO-1. These data further support the view that mild stress-induced hormesis can be applied for the modulation, intervention and prevention of aging and age-related impairments. PMID:19343114

  15. Morphological Cues for Lexical Semantics

    DTIC Science & Technology

    1996-06-01

    father, and turned thirty-graduate school has been a long varied haul and I could never have made it alone. Thus it is a good time to thank all the...distinction between world and linguistic knowledge has a long history in philosophy. Whether the distinction exists and if so how it should be drawn are...explaining human language acquisition. Language semantics cueing is more promising from a computational perspective and consequently has a long (for

  16. Hormonal status and age differentially affect tolerance to the disruptive effects of delta-9-tetrahydrocannabinol (Δ9-THC) on learning in female rats

    PubMed Central

    Winsauer, Peter J.; Filipeanu, Catalin M.; Weed, Peter F.; Sutton, Jessie L.

    2015-01-01

    The effects of hormone status and age on the development of tolerance to Δ9-THC were assessed in sham-operated (intact) or ovariectomized (OVX) female rats that received either intraperitoneal saline or 5.6 mg/kg of Δ9-THC daily from postnatal day (PD) 75–180 (early adulthood onward) or PD 35–140 (adolescence onward). During this time, the four groups for each age (i.e., intact/saline, intact/THC, OVX/saline, and OVX/THC) were trained in a learning and performance procedure and dose-effect curves were established for Δ9-THC (0.56–56 mg/kg) and the cannabinoid type-1 receptor (CB1R) antagonist rimonabant (0.32–10 mg/kg). Despite the persistence of small rate-decreasing and error-increasing effects in intact and OVX females from both ages during chronic Δ9-THC, all of the Δ9-THC groups developed tolerance. However, the magnitude of tolerance, as well as the effect of hormone status, varied with the age at which chronic Δ9-THC was initiated. There was no evidence of dependence in any of the groups. Hippocampal protein expression of CB1R, AHA1 (a co-chaperone of CB1R) and HSP90β (a molecular chaperone modulated by AHA-1) was affected more by OVX than chronic Δ9-THC; striatal protein expression was not consistently affected by either manipulation. Hippocampal brain-derived neurotrophic factor expression varied with age, hormone status, and chronic treatment. Thus, hormonal status differentially affects the development of tolerance to the disruptive effects of delta-9-tetrahydrocannabinol (Δ9-THC) on learning and performance behavior in adolescent, but not adult, female rats. These factors and their interactions also differentially affect cannabinoid signaling proteins in the hippocampus and striatum, and ultimately, neural plasticity. PMID:26191005

  17. Hormonal status and age differentially affect tolerance to the disruptive effects of delta-9-tetrahydrocannabinol (Δ(9)-THC) on learning in female rats.

    PubMed

    Winsauer, Peter J; Filipeanu, Catalin M; Weed, Peter F; Sutton, Jessie L

    2015-01-01

    The effects of hormone status and age on the development of tolerance to Δ(9)-THC were assessed in sham-operated (intact) or ovariectomized (OVX) female rats that received either intraperitoneal saline or 5.6 mg/kg of Δ(9)-THC daily from postnatal day (PD) 75-180 (early adulthood onward) or PD 35-140 (adolescence onward). During this time, the four groups for each age (i.e., intact/saline, intact/THC, OVX/saline, and OVX/THC) were trained in a learning and performance procedure and dose-effect curves were established for Δ(9)-THC (0.56-56 mg/kg) and the cannabinoid type-1 receptor (CB1R) antagonist rimonabant (0.32-10 mg/kg). Despite the persistence of small rate-decreasing and error-increasing effects in intact and OVX females from both ages during chronic Δ(9)-THC, all of the Δ(9)-THC groups developed tolerance. However, the magnitude of tolerance, as well as the effect of hormone status, varied with the age at which chronic Δ(9)-THC was initiated. There was no evidence of dependence in any of the groups. Hippocampal protein expression of CB1R, AHA1 (a co-chaperone of CB1R) and HSP90β (a molecular chaperone modulated by AHA-1) was affected more by OVX than chronic Δ(9)-THC; striatal protein expression was not consistently affected by either manipulation. Hippocampal brain-derived neurotrophic factor expression varied with age, hormone status, and chronic treatment. Thus, hormonal status differentially affects the development of tolerance to the disruptive effects of delta-9-tetrahydrocannabinol (Δ(9)-THC) on learning and performance behavior in adolescent, but not adult, female rats. These factors and their interactions also differentially affect cannabinoid signaling proteins in the hippocampus and striatum, and ultimately, neural plasticity.

  18. Semantic search via concept annealing

    NASA Astrophysics Data System (ADS)

    Dunkelberger, Kirk A.

    2007-04-01

    Annealing, in metallurgy and materials science, is a heat treatment wherein the microstructure of a material is altered, causing changes in its properties such as strength and hardness. We define concept annealing as a lexical, syntactic, and semantic expansion capability (the removal of defects and the internal stresses that cause term- and phrase-based search failure) coupled with a directed contraction capability (semantically-related terms, queries, and concepts nucleate and grow to replace those originally deformed by internal stresses). These two capabilities are tied together in a control loop mediated by the information retrieval precision and recall metrics coupled with intuition provided by the operator. The specific representations developed have been targeted at facilitating highly efficient and effective semantic indexing and searching. This new generation of Find capability enables additional processing (i.e. all-source tracking, relationship extraction, and total system resource management) at rates, precisions, and accuracies previously considered infeasible. In a recent experiment, an order magnitude reduction in time to actionable intelligence and nearly three orderss magnitude reduction in false alarm rate was achieved.

  19. Entropy, semantic relatedness and proximity.

    PubMed

    Hahn, Lance W; Sivley, Robert M

    2011-09-01

    Although word co-occurrences within a document have been demonstrated to be semantically useful, word interactions over a local range have been largely neglected by psychologists due to practical challenges. Shannon's (Bell Systems Technical Journal, 27, 379-423, 623-665, 1948) conceptualization of information theory suggests that these interactions should be useful for understanding communication. Computational advances make an examination of local word-word interactions possible for a large text corpus. We used Brants and Franz's (2006) dataset to generate conditional probabilities for 62,474 word pairs and entropy calculations for 9,917 words in Nelson, McEvoy, and Schreiber's (Behavior Research Methods, Instruments, & Computers, 36, 402-407, 2004) free association norms. Semantic associativity correlated moderately with the probabilities and was stronger when the two words were not adjacent. The number of semantic associates for a word and the entropy of a word were also correlated. Finally, language entropy decreases from 11 bits for single words to 6 bits per word for four-word sequences. The probabilities and entropies discussed here are included in the supplemental materials for the article.

  20. Differential regulation of apoptosis in slow and fast twitch muscles of aged female F344BN rats

    DOE PAGES

    Rice, Kevin M.; Manne, Nandini D. P. K.; Gadde, Murali K.; ...

    2015-03-28

    Age-related muscle atrophy is characterized by decreases in muscle mass and is thought be mediated, at least in part, by increases in myocyte apoptosis. Recent data has demonstrated that the degree of muscle loss with aging may differ between males and females while other work has suggested that apoptosis as indicated by DNA fragmentation may be regulated differently in fast- and slow-twitch muscles. Herein, we investigate how aging affects the regulation of muscle apoptosis in the fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus muscles of young (6-month), aged (26-month), and very aged (30-month) female Fischer 344/NNiaHSD × Brown Norway/BiNiamore » (F344BN) rats. Tissue sections were stained with hydroethidium for ROS and protein extract was subjected to immunoblotting for assessing apoptotic markers. Our data suggest that decreases in muscle mass were associated with increased DNA fragmentation (TUNEL positive) and increases in reactive oxygen species (ROS) as determined by hydroethidium staining in both the EDL and soleus. Similar to our previous work using aged male animals, we observed that the time course and magnitude of changes in Bax, Bcl-2, caspase-3, caspase-9, and cleavage of α-fodrin protein were regulated differently between muscles. As a result, These data suggest that aging in the female F344BN rat is associated with decreases in muscle mass, elevations in ROS level, increased muscle cell DNA fragmentation, and alterations in cell membrane integrity and that apoptotic mechanisms may differ between fiber types.« less

  1. Differential regulation of apoptosis in slow and fast twitch muscles of aged female F344BN rats

    SciTech Connect

    Rice, Kevin M.; Manne, Nandini D. P. K.; Gadde, Murali K.; Paturi, Satyanarayana; Arvapalli, Ravikumar; Blough, Eric

    2015-03-28

    Age-related muscle atrophy is characterized by decreases in muscle mass and is thought be mediated, at least in part, by increases in myocyte apoptosis. Recent data has demonstrated that the degree of muscle loss with aging may differ between males and females while other work has suggested that apoptosis as indicated by DNA fragmentation may be regulated differently in fast- and slow-twitch muscles. Herein, we investigate how aging affects the regulation of muscle apoptosis in the fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus muscles of young (6-month), aged (26-month), and very aged (30-month) female Fischer 344/NNiaHSD × Brown Norway/BiNia (F344BN) rats. Tissue sections were stained with hydroethidium for ROS and protein extract was subjected to immunoblotting for assessing apoptotic markers. Our data suggest that decreases in muscle mass were associated with increased DNA fragmentation (TUNEL positive) and increases in reactive oxygen species (ROS) as determined by hydroethidium staining in both the EDL and soleus. Similar to our previous work using aged male animals, we observed that the time course and magnitude of changes in Bax, Bcl-2, caspase-3, caspase-9, and cleavage of α-fodrin protein were regulated differently between muscles. As a result, These data suggest that aging in the female F344BN rat is associated with decreases in muscle mass, elevations in ROS level, increased muscle cell DNA fragmentation, and alterations in cell membrane integrity and that apoptotic mechanisms may differ between fiber types.

  2. Semantic priming in the prime task effect: evidence of automatic semantic processing of distractors.

    PubMed

    Marí-Beffa, P; Fuentes, L J; Catena, A; Houghton, G

    2000-06-01

    The automaticity of the semantic processing of words has been questioned because of the reduction of semantic priming when the prime word is processed nonsemantically--for example, in letter search (the prime task effect). In two experiments, prime distractor words produced semantic priming in a subsequent lexical decision task, but with the direction of priming (positive or negative) depending on the prime task. Lexico-semantic tasks produced negative semantic priming, whereas letter search produced positive semantic priming. These results are discussed in terms of task-based inhibition. We argue that, given the results from the distractors, the absence of semantic priming does not indicate an absence of semantic activation but reflects the action of control processes on prepotent responses when less practiced responses are needed.

  3. Fractional anisotropy shows differential reduction in frontal-subcortical fiber bundles—A longitudinal MRI study of 76 middle-aged and older adults

    PubMed Central

    Vik, Alexandra; Hodneland, Erlend; Haász, Judit; Ystad, Martin; Lundervold, Astri J.; Lundervold, Arvid

    2015-01-01

    Motivated by the frontal- and white matter (WM) retrogenesis hypotheses and the assumptions that fronto-striatal circuits are especially vulnerable in normal aging, the goal of the present study was to identify fiber bundles connecting subcortical nuclei and frontal areas and obtain site-specific information about age related fractional anisotropy (FA) changes. Multimodal magnetic resonance image acquisitions [3D T1-weighted and diffusion weighted imaging (DWI)] were obtained from healthy older adults (N = 76, range 49–80 years at inclusion) at two time points, 3 years apart. A subset of the participants (N = 24) was included at a third time-point. In addition to the frontal-subcortical fibers, the anterior callosal fiber (ACF) and the corticospinal tract (CST) was investigated by its mean FA together with tract parameterization analysis. Our results demonstrated fronto-striatal structural connectivity decline (reduced FA) in normal aging with substantial inter-individual differences. The tract parameterization analysis showed that the along tract FA profiles were characterized by piece-wise differential changes along their extension rather than being uniformly affected. To the best of our knowledge, this is the first longitudinal study detecting age-related changes in frontal-subcortical WM connections in normal aging. PMID:26029102

  4. Differential predation by age and sex classes in blue wildebeest in Serengeti: study of a modern carnivore den in Olduvai Gorge (Tanzania).

    PubMed

    Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel; Martínez-Maza, Cayetana; Mabulla, Audax; Baquedano, Enrique

    2015-01-01

    Age and sex selection of prey is an aspect of predator ecology which has been extensively studied in both temperate and African ecosystems. This dimension, along with fecundity, survival rates of prey and mortality factors other than predation are important in laying down the population dynamics of prey and have important implications in the management of species. A carnivore den located in the short-grassland ecological unit of the Serengeti was studied. Sex- and age- class (using five age categories) of the wildebeest remains recovered were analyzed through horn morphology, biometrics of the bones and tooth wear patterns. We compared our results with previous studies from lion and hyaena kills through multivariate analyses. Seasonality of the accumulation was analyzed through tooth histology. PCA and CVA results show that age class selection by predators depends on season, habitat-type, and growth rate of the wildebeest population. Female-biased predation was found to contradict classical hypotheses based on territorial male behaviour. The lion and spotted hyaena showed strong selection on age classes, contrary to previous studies. Migratory wildebeest sex ratio is regulated through differential predation by seasons and female deaths in the wet season are a trade-off for population stability. These data are crucial for an effective management of the species and the new method created may be useful for different carnivore species and their prey.

  5. Differential Predation by Age and Sex Classes in Blue Wildebeest in Serengeti: Study of a Modern Carnivore Den in Olduvai Gorge (Tanzania)

    PubMed Central

    Arriaza, Mari Carmen; Domínguez-Rodrigo, Manuel; Martínez-Maza, Cayetana; Mabulla, Audax; Baquedano, Enrique

    2015-01-01

    Age and sex selection of prey is an aspect of predator ecology which has been extensively studied in both temperate and African ecosystems. This dimension, along with fecundity, survival rates of prey and mortality factors other than predation are important in laying down the population dynamics of prey and have important implications in the management of species. A carnivore den located in the short-grassland ecological unit of the Serengeti was studied. Sex- and age- class (using five age categories) of the wildebeest remains recovered were analyzed through horn morphology, biometrics of the bones and tooth wear patterns. We compared our results with previous studies from lion and hyaena kills through multivariate analyses. Seasonality of the accumulation was analyzed through tooth histology. PCA and CVA results show that age class selection by predators depends on season, habitat-type, and growth rate of the wildebeest population. Female-biased predation was found to contradict classical hypotheses based on territorial male behaviour. The lion and spotted hyaena showed strong selection on age classes, contrary to previous studies. Migratory wildebeest sex ratio is regulated through differential predation by seasons and female deaths in the wet season are a trade-off for population stability. These data are crucial for an effective management of the species and the new method created may be useful for different carnivore species and their prey. PMID:26017363

  6. Semantic Deficits in Spanish-English Bilingual Children with Language Impairment

    ERIC Educational Resources Information Center

    Sheng, Li; Pena, Elizabeth D.; Bedore, Lisa M.; Fiestas, Christine E.

    2012-01-01

    Purpose: To examine the nature and extent of semantic deficits in bilingual children with language impairment (LI). Method: Thirty-seven Spanish-English bilingual children with LI (ranging from age 7;0 [years;months] to 9;10) and 37 typically developing (TD) age-matched peers generated 3 associations to 12 pairs of translation equivalents in…

  7. On the Threshold of the Storyrealm: Semantic versus Pragmatic Use of Connectives in Narratives.

    ERIC Educational Resources Information Center

    Peterson, Carole; McCabe, Allyssa

    1991-01-01

    Presents analyses of the use of the essential connectives "so,""because,""then," and "but" in narratives of children aged three to nine years. Connectives were used semantically, pragmatically, or, rarely, in error. Age changes were minimal. Structural complexity and elaboration improved throughout the…

  8. Loss of CB1 receptors leads to differential age-related changes in reward-driven learning and memory

    PubMed Central

    Albayram, Onder; Bilkei-Gorzo, Andras; Zimmer, Andreas

    2012-01-01

    Previous studies have shown that cannabinoid 1 (CB1) receptor signaling dissociates between reward-associated and aversive memories. The influence of CB1 receptors on the aversion-driven spatial learning in the Morris water maze test is strongly age-dependent: mice with genetic deletion of CB1 receptors (Cnr1−/−) show superior learning when young but inferior learning when old compared to age-matched wild-type mice. Whether the reward-driven spatial learning is influenced in the same way by CB1 receptor signaling as the aversion-driven learning remains unclear. Thus, we examined the performance of Cn1−/− and their wild-type littermates at ages of 2-, 5-, and 12-months-old in the eight-arm radial maze test—a reward-motivated model of spatial learning. Interestingly, 2-months-old Cnr1−/− mice had a superior learning ability to wild-type mice. At the age of 5-months, Cnr1−/− mice showed the same performance as the wild-type littermates. However, 12-months-old Cnr1−/− mice showed significantly impaired performances in each parameter of the test. Accordingly, this study provides compelling support for our previous result that genetic deletion of CB1 receptor leads to early onset of age-related memory decline, similarly affecting both reward and aversion-driven learning. PMID:23227007

  9. Age matters: differential impact of service quality on contraceptive uptake among post-abortion clients in Kenya.

    PubMed

    Tavrow, Paula; Withers, Mellissa; McMullen, Kara

    2012-01-01

    This paper analyses the impact of high quality, user-friendly, comprehensive sliding-scale post-abortion services on clients' uptake of contraception in a Kenyan town. Data were drawn from detailed physician records in a private clinic that served 1080 post-abortion clients in 2006. All clients received confidential family planning counselling and were offered a complete range of contraceptives at no additional cost. One quarter of clients were below age 19. Prior to the abortion, no client aged 10-18 years reported having used contraception, as compared to 60% of clients aged 27-46 years. After the abortion and family planning counselling session, only 6% of clients aged 10-18 chose a method, as compared to 96% of clients aged 27-46, even though contraception was free, the provider strongly promoted family planning to everyone and all clients had just experienced an unwanted pregnancy. Significant predictors of contraceptive uptake post-abortion were: having a child, a previous termination, prior contraceptive use and being older than 21. These findings suggest that availability, affordability and youth-friendliness are not sufficient to overcome psycho-social barriers to contraceptive use for sexually-active young people in Kenya. To reduce unwanted pregnancies, more attention may be needed to developing youth-friendly communities that support responsible sexuality among adolescents.

  10. Age, differential growth and mortality rates in unexploited populations of Florida gar, an apex predator in the Florida Everglades

    USGS Publications Warehouse

    Murie, D.J.; Parkyn, D.C.; Nico, L.G.; Herod, J.J.; Loftus, W.F.

    2009-01-01

    Florida gar, Lepisosteus platyrhincus DeKay, were sampled in two canal systems in south Florida during 2000-2001 to estimate age, growth and mortality as part of the Everglades ecosystem-restoration effort. Tamiami (C-4) and L-31W canal systems had direct connections to natural wetlands of the Everglades and harboured large Florida gar populations. Of 476 fish aged, maximum ages were 19 and 10years for females and males, respectively. Maximum sizes were also larger for females compared with males (817 vs 602 mm total length). Overall, female Florida gar from both Tamiami and L-31W were larger at age than males from L-31W that, in turn, were larger at any given age than males from Tamiami. Females also had lower rates of annual mortality (Z = 0.21) than males from L-31W (Z = 0.31) or males from Tamiami (Z = 0.54). As a large and long-lived apex predator in the Everglades, Florida gar may structure lower trophic levels. Regional- and sex-specific population parameters for Florida gar will contribute to the simulation models designed to evaluate Everglades restoration alternatives. ?? 2009 Blackwell Publishing Ltd.

  11. Lipid-laden cells differentially distributed in the aging brain are functionally active and correspond to distinct phenotypes.

    PubMed

    Shimabukuro, Marilia Kimie; Langhi, Larissa Gutman Paranhos; Cordeiro, Ingrid; Brito, José M; Batista, Claudia Maria de Castro; Mattson, Mark P; Mello Coelho, Valeria de

    2016-03-31

    We characterized cerebral Oil Red O-positive lipid-laden cells (LLC) of aging mice evaluating their distribution, morphology, density, functional activities and inflammatory phenotype. We identified LLC in meningeal, cortical and neurogenic brain regions. The density of cerebral LLC increased with age. LLC presenting small lipid droplets were visualized adjacent to blood vessels or deeper in the brain cortical and striatal parenchyma of aging mice. LLC with larger droplets were asymmetrically distributed in the cerebral ventricle walls, mainly located in the lateral wall. We also found that LLC in the subventricular region co-expressed beclin-1 or LC3, markers for autophagosome or autophagolysosome formation, and perilipin (PLIN), a lipid droplet-associated protein, suggesting lipophagic activity. Some cerebral LLC exhibited β galactosidase activity indicating a senescence phenotype. Moreover, we detected production of the pro-inflammatory cytokine TNF-α in cortical PLIN(+) LLC. Some cortical NeuN(+) neurons, GFAP(+) glia limitans astrocytes, Iba-1(+) microglia and S100β(+) ependymal cells expressed PLIN in the aging brain. Our findings suggest that cerebral LLC exhibit distinct cellular phenotypes and may participate in the age-associated neuroinflammatory processes.

  12. “Pre-semantic” cognition revisited: Critical differences between semantic aphasia and semantic dementia

    PubMed Central

    Jefferies, Elizabeth; Rogers, Timothy T.; Hopper, Samantha; Lambon Ralph, Matthew A.

    2009-01-01

    Patients with semantic dementia show a specific pattern of impairment on both verbal and non-verbal “pre-semantic” tasks: e.g., reading aloud, past tense generation, spelling to dictation, lexical decision, object decision, colour decision and delayed picture copying. All seven tasks are characterised by poorer performance for items that are atypical of the domain and “regularisation errors” (irregular/atypical items are produced as if they were domain-typical). The emergence of this pattern across diverse tasks in the same patients indicates that semantic memory plays a key role in all of these types of “pre-semantic” processing. However, this claim remains controversial because semantically-impaired patients sometimes fail to show an influence of regularity. This study demonstrates that (a) the location of brain damage and (b) the underlying nature of the semantic deficit affect the likelihood of observing the expected relationship between poor comprehension and regularity effects. We compared the effect of multimodal semantic impairment in the context of semantic dementia and stroke aphasia on the seven “pre-semantic” tasks listed above. In all of these tasks, the semantic aphasia patients were less sensitive to typicality than the semantic dementia patients, even though the two groups obtained comparable scores on semantic tests. The semantic aphasia group also made fewer regularisation errors and many more unrelated and perseverative responses. We propose that these group differences reflect the different locus for the semantic impairment in the two conditions: patients with semantic dementia have degraded semantic representations, whereas semantic aphasia patients show deregulated semantic cognition with concomitant executive deficits. These findings suggest a reinterpretation of single case studies of comprehension-impaired aphasic patients who fail to show the expected effect of regularity on “pre-semantic” tasks. Consequently, such

  13. Effect of Paullinia cupana Mart. Commercial Extract During the Aging of Middle Age Wistar Rats: Differential Effects on the Hippocampus and Striatum.

    PubMed

    Mingori, Moara Rodrigues; Heimfarth, Luana; Ferreira, Charles Francisco; Gomes, Henrique Mautone; Moresco, Karla Suzana; Delgado, Jeferson; Roncato, Sabrina; Zeidán-Chuliá, Fares; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca

    2017-03-27

    During aging, there is a marked decline in the antioxidant capacity of brain tissue, leading to a gradual loss of the antioxidant/oxidant balance, which causes oxidative damage. The effects of Paullinia cupana Mart. extract, which is described as being rich in caffeine and many polyphenol compounds, on the central nervous system have not been extensively investigated. The aim of this study was to therefore investigate the effect of a commercial guarana extract (CGE) on cognitive function, oxidative stress, and brain homeostasis proteins related to cognitive injury and senescence in middle age, male Wistar rats. Animals were randomly assigned to a group according to their treatment (saline, CGE, or caffeine). Solutions were administered daily by oral gavage for 6 months. Open field and novel object recognition tasks were performed before and after treatment. Biochemical analyses were carried out on the hippocampus and striatum. Our open field data showed an increase in exploratory activity and a decrease in anxiety-like behavior with caffeine but not with the CGE treatment. In the CGE-treated group, catalase activity decreased in the hippocampus and increased in the striatum. Analyses of the hippocampus and striatum indicate that CGE and/or caffeine altered some of the analyzed parameters in a tissue-specific manner. Our data suggest that CGE intake does not improve cognitive development, but modifies the oxidative stress machinery and neurodegenerative-signaling pathway, inhibiting pro-survival pathway molecules in the hippocampus and striatum. This may contribute to the development of unfavorable microenvironments in the brain and neurodegenerative disorders.

  14. Differential proteomic and oxidative profiles unveil dysfunctional protein import to adipocyte mitochondria in obesity-associated aging and diabetes.

    PubMed

    Gómez-Serrano, María; Camafeita, Emilio; López, Juan A; Rubio, Miguel A; Bretón, Irene; García-Consuegra, Inés; García-Santos, Eva; Lago, Jesús; Sánchez-Pernaute, Andrés; Torres, Antonio; Vázquez, Jesús; Peral, Belén

    2017-04-01

    Human age-related diseases, including obesity and type 2 diabetes (T2DM), have long been associated to mitochondrial dysfunction; however, the role for adipose tissue mitochondria in these conditions remains unknown. We have tackled the impact of aging and T2DM on adipocyte mitochondria from obese patients by quantitating not only the corresponding abundance changes of proteins, but also the redox alterations undergone by Cys residues thereof. For that, we have resorted to a high-throughput proteomic approach based on isobaric labeling, liquid chromatography and mass spectrometry. The alterations undergone by the mitochondrial proteome revealed aging- and T2DM-specific hallmarks. Thus, while a global decrease of oxidative phosphorylation (OXPHOS) subunits was found in aging, the diabetic patients exhibited a reduction of specific OXPHOS complexes as well as an up-regulation of the anti-oxidant response. Under both conditions, evidence is shown for the first time of a link between increased thiol protein oxidation and decreased protein abundance in adipose tissue mitochondria. This association was stronger in T2DM, where OXPHOS mitochondrial- vs. nuclear-encoded protein modules were found altered, suggesting impaired mitochondrial protein translocation and complex assembly. The marked down-regulation of OXPHOS oxidized proteins and the alteration of oxidized Cys residues related to protein import through the redox-active MIA (Mitochondrial Intermembrane space Assembly) pathway support that defects in protein translocation to the mitochondria may be an important underlying mechanism for mitochondrial dysfunction in T2DM and physiological aging. The present draft of redox targets together with the quantification of protein and oxidative changes may help to better understand the role of oxidative stress in both a physiological process like aging and a pathological condition like T2DM.

  15. Nitric oxide availability is increased in contracting skeletal muscle from aged mice, but does not differentially decrease muscle superoxide.

    PubMed

    Pearson, T; McArdle, A; Jackson, M J

    2015-01-01

    Reactive oxygen and nitrogen species have been implicated in the loss of skeletal muscle mass and function that occurs during aging. Nitric oxide (NO) and superoxide are generated by skeletal muscle and where these are generated in proximity their chemical reaction to form peroxynitrite can compete with the superoxide dismutation to hydrogen peroxide. Changes in NO availability may therefore theoretically modify superoxide and peroxynitrite activities in tissues, but published data are contradictory regarding aging effects on muscle NO availability. We hypothesised that an age-related increase in NO generation might increase peroxynitrite generation in muscles from old mice, leading to an increased nitration of muscle proteins and decreased superoxide availability. This was examined using fluorescent probes and an isolated fiber preparation to examine NO content and superoxide in the cytosol and mitochondria of muscle fibers from adult and old mice both at rest and following contractile activity. We also examined the 3-nitrotyrosine (3-NT) and peroxiredoxin 5 (Prx5) content of muscles from mice as markers of peroxynitrite activity. Data indicate that a substantial age-related increase in NO levels occurred in muscle fibers during contractile activity and this was associated with an increase in muscle eNOS. Muscle proteins from old mice also showed an increased 3-NT content. Inhibition of NOS indicated that NO decreased superoxide bioavailability in muscle mitochondria, although this effect was not age related. Thus increased NO in muscles of old mice was associated with an increased 3-NT content that may potentially contribute to age-related degenerative changes in skeletal muscle.

  16. Secondhand tobacco smoke exposure differentially alters nucleus tractus solitarius neurons at two different ages in developing non-human primates

    SciTech Connect

    Sekizawa, Shin-ichi; Joad, Jesse P.; Pinkerton, Kent E.; Bonham, Ann C.

    2010-01-15

    Exposing children to secondhand tobacco smoke (SHS) is associated with increased risk for asthma, bronchiolitis and SIDS. The role for changes in the developing CNS contributing to these problems has not been fully explored. We used rhesus macaques to test the hypothesis that SHS exposure during development triggers neuroplastic changes in the nucleus tractus solitarius (NTS), where lung sensory information related to changes in airway and lung function is first integrated. Pregnant monkeys were exposed to filtered air (FA) or SHS for 6 h/day, 5 days/week starting at 50-day gestational age. Mother/infant pairs continued the exposures postnatally to age 3 or 13 months, which may be equivalent to approximately 1 or 4 years of human age, respectively. Whole-cell recordings were made of second-order NTS neurons in transverse brainstem slices. To target the consequences of SHS exposure based on neuronal subgroups, we classified NTS neurons into two phenotypes, rapid-onset spiking (RS) and delayed-onset spiking (DS), and then evaluated intrinsic and synaptic excitabilities in FA-exposed animals. RS neurons showed greater cell excitability especially at age of 3 months while DS neurons received greater amplitudes of excitatory postsynaptic currents (EPSCs). Developmental neuroplasticity such as increases in intrinsic and synaptic excitabilities were detected especially in DS neurons. In 3 month olds, SHS exposure effects were limited to excitatory changes in RS neurons, specifically increases in evoked EPSC amplitudes and increased spiking responses accompanied by shortened action potential width. By 13 months, the continued SHS exposure inhibited DS neuronal activity; decreases in evoked EPSC amplitudes and blunted spiking responses accompanied by prolonged action potential width. The influence of SHS exposure on age-related and phenotype specific changes may be associated with age-specific respiratory problems, for which SHS exposure can increase the risk, such as SIDS

  17. Semantic Knowledge Use in Discourse Produced by Individuals with Anomic Aphasia

    PubMed Central

    Kintz, Stephen; Wright, Heather Harris; Fergadiotis, Gerasimos

    2015-01-01

    Background Researchers have demonstrated that people with aphasia (PWA) have preserved semantic knowledge (Dell et al., 1997; Jefferies & Lambon Ralph, 2006). However, Antonucci (2014) demonstrated that some PWA have impaired access to certain types of knowledge more than others. Yet, all these studies used single concepts. It has not been demonstrated whether PWA have difficulty accessing certain types of features within a discourse sample. Aims The main goals of this study were to determine if semantic knowledge and two category types were used differently within discourse produced by participants with anomic aphasia and healthy controls. Method & Procedures Participants with anomic aphasia (n=19) and healthy controls (n=19) told stories that were transcribed and coded for 10 types of semantic knowledge and two category types, living and nonliving things. Outcomes & Results A Poisson regression model was conducted. The results indicated a significant difference between the groups for the semantic knowledge types, sound and internal state, but no difference was found for category types. Yet the distribution of semantic knowledge and category types produced within the discourse samples were similar between the groups. Conclusion PWA might have differential access to certain types of semantic knowledge within discourse production, but it does not rise to the level of categorical deficits. These findings extend single-concept research into the realm of discourse. PMID:27429506

  18. Individual Differences in Working Memory Capacity Modulates Semantic Negative Priming from Single Prime Words

    PubMed Central

    Ortells, Juan J.; Noguera, Carmen; Álvarez, Dolores; Carmona, Encarna; Houghton, George

    2016-01-01

    The present study investigated whether semantic negative priming from single prime words depends on the availability of cognitive control resources. Participants with high vs. low working memory capacity (as assessed by their performance in complex span and attentional control tasks) were instructed to either attend to or ignore a briefly presented single prime word that was followed by either a semantically related or unrelated target word on which participants made a lexical decision. Individual differences in working memory capacity (WMC) mainly affected the processing of the ignored primes, but not the processing of the attended primes: While the latter produced reliable positive semantic priming for both high- and low-WMC participants, the former gave rise to reliable semantic negative priming only for high WMC participants, with low WMC participants showing the opposite positive priming effect. The present results extend previous findings in demonstrating that (a) single negative priming can reliably generalize to semantic associates of the prime words, and (b) a differential availability of cognitive control resources can reliably modulate the negative priming effect at a semantic level of representation. PMID:27621716

  19. Verbal Description of Concrete Objects: A Method for Assessing Semantic Circumlocution in Persons With Aphasia

    PubMed Central

    MacWilliam, Colleen

    2015-01-01

    Purpose We investigated from a theoretically motivated perspective what information differentiated sufficient from insufficient descriptions of objects provided by persons with aphasia. Method Twenty-one adults with aphasia consequent to single left-hemisphere stroke verbally described 9 living and 9 nonliving objects. Responses were scored for accuracy (i.e., sufficiency) and tallied for type and quantity of semantic feature information provided. Main effects and interactions were identified using repeated measures analyses of variance, with significant findings followed up with planned comparisons. Results Differences between correct and incorrect descriptions were identified with respect to both feature type and feature distinctiveness for living and nonliving items, in particular highlighting the importance of distinctive features in descriptions of both domains. Conclusions These findings add to the relatively small body of literature investigating semantic feature processing in adults with aphasia. This is a critical gap to close when considered in light of the preponderance of semantically based treatments for word-retrieval impairment in stroke-aphasia. Our findings provide preliminary support for the notion that semantically guided treatments for word-retrieval impairment in stroke-aphasia may be geared toward increasing specificity of semantic circumlocution to increase semantic self-cueing and to improve communication of information to conversation partners. PMID:26381474

  20. Neuroanatomic substrates of semantic memory impairment in Alzheimer’s disease: Patterns of functional MRI activation

    PubMed Central

    SAYKIN, ANDREW J.; FLASHMAN, LAURA A.; FRUTIGER, SALLY A.; JOHNSON, STERLING C.; MAMOURIAN, ALEXANDER C.; MORITZ, CHAD H.; O’JILE, JUDITH R.; RIORDAN, HENRY J.; SANTULLI, ROBERT B.; SMITH, CYNTHIA A.; WEAVER, JOHN B.

    2015-01-01

    Impairment in semantic processing occurs early in Alzheimer’s disease (AD) and differential impact on subtypes of semantic relations have been reported, yet there is little data on the neuroanatomic basis of these deficits. Patients with mild AD and healthy controls underwent 3 functional MRI auditory stimulation tasks requiring semantic or phonological decisions (match–mismatch) about word pairs (category–exemplar, category–function, pseudoword). Patients showed a significant performance deficit only on the exemplar task. On voxel-based fMRI activation analyses, controls showed a clear activation focus in the left superior temporal gyrus for the phonological task; patients showed additional foci in the left dorsolateral prefrontal and bilateral cingulate areas. On the semantic tasks, predominant activation foci were seen in the inferior and middle frontal gyrus (left greater than right) in both groups but patients showed additional activation suggesting compensatory recruitment of locally expanded foci and remote regions, for example, right frontal activation during the exemplar task. Covariance analyses indicated that exemplar task performance was strongly related to signal increase in bilateral medial prefrontal cortex. The authors conclude that fMRI can reveal similarities and differences in functional neuroanatomical processing of semantic and phonological information in mild AD compared to healthy elderly, and can help to bridge cognitive and neural investigations of the integrity of semantic networks in AD. PMID:10439584

  1. Individual Differences in Working Memory Capacity Modulates Semantic Negative Priming from Single Prime Words.

    PubMed

    Ortells, Juan J; Noguera, Carmen; Álvarez, Dolores; Carmona, Encarna; Houghton, George

    2016-01-01

    The present study investigated whether semantic negative priming from single prime words depends on the availability of cognitive control resources. Participants with high vs. low working memory capacity (as assessed by their performance in complex span and attentional control tasks) were instructed to either attend to or ignore a briefly presented single prime word that was followed by either a semantically related or unrelated target word on which participants made a lexical decision. Individual differences in working memory capacity (WMC) mainly affected the processing of the ignored primes, but not the processing of the attended primes: While the latter produced reliable positive semantic priming for both high- and low-WMC participants, the former gave rise to reliable semantic negative priming only for high WMC participants, with low WMC participants showing the opposite positive priming effect. The present results extend previous findings in demonstrating that (a) single negative priming can reliably generalize to semantic associates of the prime words, and (b) a differential availability of cognitive control resources can reliably modulate the negative priming effect at a semantic level of representation.

  2. Evidence for a dissociation of structural and semantic knowledge in dementia of the Alzheimer type (DAT).

    PubMed

    Hajilou, B Bruce; Done, D John

    2007-03-02

    Object recognition and naming deficits in dementia of the Alzheimer type (DAT) have typically been attributed to deficits in semantic processing, with only a few studies proposing loci of deficits other than semantic. One possible cause of DAT object recognition impairments could involve deficits in processing structural aspects of visually presented items. In this paper, we assess the performance of a group of mild DAT patients on two tasks of structural access, object decision, and the complete/incomplete task (based on part-whole matching task), as well as on a semantic probes task, designed to assess the patients' semantic knowledge of the same items for which structural knowledge had earlier been assessed. The DAT patients were substantially impaired in their performance on tasks of structural access. Further, no evidence for item-to-item consistency in the DAT patients' errors for the structural and semantic tasks was found, raising the possibility that structural and semantic knowledge may become differentially impaired in DAT.

  3. Neuropsychological differentiation of adaptive creativity and schizotypal cognition

    PubMed Central

    Fisher, Joscelyn E.; Heller, Wendy; Miller, Gregory A.

    2012-01-01

    Both creativity and schizophrenia-spectrum disorders have been associated with activation of remote semantic concepts, but this activation results in innovative output in one case and communication disturbances in the other. The present study examined the relationship between monitoring semantic information (which relies on executive brain function), creativity, and characteristics of schizotypy in an undergraduate population. Results indicate that executive function differentiates the use of semantic information in creativity and schizotypy. Specification of the balance between executive monitoring and activation of semantic information is important for determining how communication disturbances manifest, and for the measurement of creativity and schizotypy in the general population. PMID:23109749

  4. Neuropsychological differentiation of adaptive creativity and schizotypal cognition.

    PubMed

    Fisher, Joscelyn E; Heller, Wendy; Miller, Gregory A

    2013-01-01

    Both creativity and schizophrenia-spectrum disorders have been associated with activation of remote semantic concepts, but this activation results in innovative output in one case and communication disturbances in the other. The present study examined the relationship between monitoring semantic information (which relies on executive brain function), creativity, and characteristics of schizotypy in an undergraduate population. Results indicate that executive function differentiates the use of semantic information in creativity and schizotypy. Specification of the balance between executive monitoring and activation of semantic information is important for determining how communication disturbances manifest, and for the measurement of creativity and schizotypy in the general population.

  5. SSWAP: A Simple Semantic Web Architecture and Protocol for Semantic Web Services

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SSWAP (Simple Semantic Web Architecture and Protocol) is an architecture, protocol, and platform for using reasoning to semantically integrate heterogeneous disparate data and services on the web. SSWAP is the driving technology behind the Virtual Plant Information Network, an NSF-funded semantic w...

  6. Explaining semantic short-term memory deficits: Evidence for the critical role of semantic control

    PubMed Central

    Hoffman, Paul; Jefferies, Elizabeth; Lambon Ralph, Matthew A.

    2011-01-01

    Patients with apparently selective short-term memory (STM) deficits for semantic information have played an important role in developing multi-store theories of STM and challenge the idea that verbal STM is supported by maintaining activation in the language system. We propose that semantic STM deficits are not as selective as previously thought and can occur as a result of mild disruption to semantic control processes, i.e., mechanisms that bias semantic processing towards task-relevant aspects of knowledge and away from irrelevant information. We tested three semantic STM patients with tasks that tapped four aspects of semantic control: (i) resolving ambiguity between word meanings, (ii) sensitivity to cues, (iii) ignoring irrelevant information and (iv) detecting weak semantic associations. All were impaired in conditions requiring more semantic control, irrespective of the STM demands of the task, suggesting a mild, but task-general, deficit in regulating semantic knowledge. This mild deficit has a disproportionate effect on STM tasks because they have high intrinsic control demands: in STM tasks, control is required to keep information active when it is no longer available in the environment and to manage competition between items held in memory simultaneously. By re-interpreting the core deficit in semantic STM patients in this way, we are able to explain their apparently selective impairment without the need for a specialised STM store. Instead, we argue that semantic STM patients occupy the mildest end of spectrum of semantic control disorders. PMID:21195105

  7. Representations for Semantic Learning Webs: Semantic Web Technology in Learning Support

    ERIC Educational Resources Information Center

    Dzbor, M.; Stutt, A.; Motta, E.; Collins, T.

    2007-01-01

    Recent work on applying semantic technologies to learning has concentrated on providing novel means of accessing and making use of learning objects. However, this is unnecessarily limiting: semantic technologies will make it possible to develop a range of educational Semantic Web services, such as interpretation, structure-visualization, support…

  8. Semantic Clustering of Search Engine Results

    PubMed Central

    Soliman, Sara Saad; El-Sayed, Maged F.; Hassan, Yasser F.

    2015-01-01

    This paper presents a novel approach for search engine results clustering that relies on the semantics of the retrieved documents rather than the terms in those documents. The proposed approach takes into consideration both lexical and semantics similarities among documents and applies activation spreading technique in order to generate semantically meaningful clusters. This approach allows documents that are semantically similar to be clustered together rather than clustering documents based on similar terms. A prototype is implemented and several experiments are conducted to test the prospered solution. The result of the experiment confirmed that the proposed solution achieves remarkable results in terms of precision. PMID:26933673

  9. Synonyms Provide Semantic Preview Benefit in English

    PubMed Central

    Schotter, Elizabeth R.

    2013-01-01

    While orthographic and phonological preview benefits in reading are uncontroversial (see Schotter, Angele, & Rayner, 2012 for a review), researchers have debated the existence of semantic preview benefit with positive evidence in Chinese and German, but no support in English. Two experiments, using the gazecontingent boundary paradigm (Rayner, 1975), show that semantic preview benefit can be observed in English when the preview and target are synonyms (share the same or highly similar meaning, e.g., curlers-rollers). However, no semantic preview benefit was observed for semantic associates (e.g., curlers-styling). These different preview conditions represent different degrees to which the meaning of the sentence changes when the preview is replaced by the target. When this continuous variable (determined by a norming procedure) was used as the predictor in the analyses, there was a significant relationship between it and all reading time measures, suggesting that similarity in meaning between what is accessed parafoveally and what is processed foveally may be an important influence on the presence of semantic preview benefit. Why synonyms provide semantic preview benefit in reading English is discussed in relation to (1) previous failures to find semantic preview benefit in English and (2) the fact that semantic preview benefit is observed in other languages even for non-synonymous words. Semantic preview benefit is argued to depend on several factors—attentional resources, depth of orthography, and degree of similarity between preview and target. PMID:24347813

  10. Similarity Based Semantic Web Service Match

    NASA Astrophysics Data System (ADS)

    Peng, Hui; Niu, Wenjia; Huang, Ronghuai

    Semantic web service discovery aims at returning the most matching advertised services to the service requester by comparing the semantic of the request service with an advertised service. The semantic of a web service are described in terms of inputs, outputs, preconditions and results in Ontology Web Language for Service (OWL-S) which formalized by W3C. In this paper we proposed an algorithm to calculate the semantic similarity of two services by weighted averaging their inputs and outputs similarities. Case study and applications show the effectiveness of our algorithm in service match.

  11. Gender and age effects interact in preschoolers' help-seeking: evidence for differential responses to changes in task difficulty.

    PubMed

    Thompson, R Bruce; Cothran, Thomas; McCall, Daniel

    2012-11-01

    This study explored preschool age and gender differences in help-seeking within the theoretical framework of scaffolded problem-solving and self-regulation (Bruner, 1986; Rogoff, 1990; Vygotsky, 1978; 1986). Within-subject analyses tracked changes in help-seeking among 62 preschoolers (34 boys, 28 girls, mean age 4.22 years) solving a challenging puzzle with an adult. The goal was to document whether age and gender interact with fluctuating difficulty to affect children's spontaneous help-seeking. ANOVAs indicated that girls used more help-seeking during difficult segments of the task, despite performance equal to the boys. This pattern was strongest among older girls, who outperformed all other children and used the most help-seeking. Partial correlations, controlling for solving time, indicated that age predicted children's help-seeking during the most difficult segments of the task, but only among girls. Gender differences in social-linguistic maturation and cognitive development are discussed within the framework of Vygotskian theory and related educational practice.

  12. Mental Health of Lesbian, Gay, and Bisexual Youth and Young Adults: Differential Effects of Age, Gender, Religiosity, and Sexual Orientation

    ERIC Educational Resources Information Center

    Shilo, Guy; Savaya, Riki

    2012-01-01

    Drawing on minority stress theory, this study examined the mental health effects of the added burden of disadvantaged social status in an Israeli sample of 461 self-identified lesbian, gay, and bisexual (LGB) youths. Bisexuality was associated with lower levels of well-being, and, at a younger age, with higher levels of mental distress. In…

  13. Aging White Matter and Cognition: Differential Effects of Regional Variations in Diffusion Properties on Memory, Executive Functions, and Speed

    ERIC Educational Resources Information Center

    Kennedy, Kristen M.; Raz, Naftali

    2009-01-01

    Disruption of cerebral white matter has been proposed as an explanation for age-related cognitive declines. However, the role of specific regions in specific cognitive declines remains unclear. We used diffusion tensor imaging to examine the associations between regional microstructural integrity of the white matter and performance on…

  14. Effect of CMV and Aging on the Differential Expression of CD300a, CD161, T-bet, and Eomes on NK Cell Subsets.

    PubMed

    Lopez-Sejas, Nelson; Campos, Carmen; Hassouneh, Fakhri; Sanchez-Correa, Beatriz; Tarazona, Raquel; Pera, Alejandra; Solana, Rafael

    2016-01-01

    Natural killer (NK) cells are innate lymphoid cells involved in the defense against virus-infected cells and tumor cells. NK cell phenotype and function is affected with age and cytomegalovirus (CMV) latent infection. Aging affects the frequency and phenotype of NK cells, and CMV infection also contributes to these alterations. Thus, a reduction of CD56(bright) NK cell subpopulation associated with age and an expansion of memory-like NK cells CD56(dim)CD57(+)NKG2C(+) probably related to CMV seropositivity have been described. NK cells express T-bet and Eomes transcription factors that are necessary for the development of NK cells. Here, we analyze the effect of age and CMV seropositivity on the expression of CD300a and CD161 inhibitory receptors, and T-bet and Eomes transcription factors in NK cell subsets defined by the expression of CD56 and CD57. CD300a is expressed by the majority of NK cells. CD56(bright) NK cells express higher levels of CD300a than CD56(dim) NK cells. An increase in the expression of CD300a was associated with age, whereas a decreased expression of CD161 in CD56(dim) NK cells was associated with CMV seropositivity. In CD56(dim) NK cells, an increased percentage of CD57(+)CD300a(+) and a reduction in the percentage of CD161(+)CD300a(+) cells were found to be associated with CMV seropositivity. Regarding T-bet and Eomes transcription factors, CMV seropositivity was associated with a decrease of T-bet(hi) in CD56(dim)CD57(+) NK cells from young individuals, whereas Eomes expression was increased with CMV seropositivity in both CD56(bright) and CD56(dim)CD57(+/-) (from middle age and young individuals, respectively) and was decreased with aging in all NK subsets from the three group of age. In conclusion, CMV infection and age induce significant changes in the expression of CD300a and CD161 in NK cell subsets defined by the expression of CD56 and CD57. T-bet and Eomes are differentially expressed on NK cell subsets, and their expression is

  15. An Analysis of the Semantic Relationships Among Words and Their Effect Upon Learning. Final Report.

    ERIC Educational Resources Information Center

    Weber, James M.

    The purpose of this study was to (1) compare the semantic relationships among common nouns obtained via two different measurement procedures and (2) determine if the use of these relationships to classify the various words results in differential degrees of learning when the stimuli are cast in terms of the paired-associate learning paradigm.…

  16. p38α MAPK regulates proliferation and differentiation of osteoclast progenitors and bone remodeling in an aging-dependent manner

    PubMed Central

    Cong, Qian; Jia, Hao; Li, Ping; Qiu, Shoutao; Yeh, James; Wang, Yibin; Zhang, Zhen-Lin; Ao, Junping; Li, Baojie; Liu, Huijuan

    2017-01-01

    Bone mass is determined by the balance between bone formation, carried out by mesenchymal stem cell-derived osteoblasts, and bone resorption, carried out by monocyte-derived osteoclasts. Here we investigated the potential roles of p38 MAPKs, which are activated by growth factors and cytokines including RANKL and BMPs, in osteoclastogenesis and bone resorption by ablating p38α MAPK in LysM+monocytes. p38α deficiency promoted monocyte proliferation but regulated monocyte osteoclastic differentiation in a cell-density dependent manner, with proliferating p38α−/− cultures showing increased differentiation. While young mutant mice showed minor increase in bone mass, 6-month-old mutant mice developed osteoporosis, associated with an increase in osteoclastogenesis and bone resorption and an increase in the pool of monocytes. Moreover, monocyte-specific p38α ablation resulted in a decrease in bone formation and the number of bone marrow mesenchymal stem/stromal cells, likely due to decreased expression of PDGF-AA and BMP2. The expression of PDGF-AA and BMP2 was positively regulated by the p38 MAPK-Creb axis in osteoclasts, with the promoters of PDGF-AA and BMP2 having Creb binding sites. These findings uncovered the molecular mechanisms by which p38α MAPK regulates osteoclastogenesis and coordinates osteoclastogenesis and osteoblastogenesis. PMID:28382965

  17. Differential association of socio-economic status with gender- and age-defined suicidal ideation among adult and elderly individuals in South Korea.

    PubMed

    Lee, Hoo-Yeon; Hahm, Myung-Il; Park, Eun-Cheol

    2013-11-30

    South Korea has the highest suicide rate among countries in the Organisation for Economic Co-operation and Development (OECD), with a rising trend that contrasts with the trend in most other OECD countries. This study assessed differential associations of socio-demographic factors with suicidal ideation in South Korea. We used five waves of data from the 2010 Korea National Health and Nutrition Examination Survey. Study subjects included 5803 men and women aged >25 years. We analysed weighted percentages with consideration of the complex survey sample design and unequal weights. Surveylogistic regressions were applied. Protective effects against suicidal ideation were found for higher household income, higher educational attainment, and being married. Functional limitations and depressive symptoms were risk factors for suicidal ideation. However, these significant factors may exert different effects on vulnerability for suicidal ideation among different genders and age groups. Thus, household income was mainly protective for women and subjects aged 25-44 years, and educational attainment was protective for individuals aged >65 years. Our findings suggest the need for extended social protection policies for the less privileged population and special strategies for different groups.

  18. The effects of high-dose methamphetamine in the aging rat: differential reinforcement of low-rate 72-s schedule behavior and neurochemistry.

    PubMed

    Sabol, K E; Richards, J B; Yung, K

    2000-09-01

    High-dose methamphetamine (METH) causes damage to the dopamine and serotonin neurons in the brains of laboratory animals. The purpose of this report was to determine the long-term consequences of high-dose METH treatment on behavior and neurochemistry. Rats were trained on the differential reinforcement of low-rate 72-s (DRL 72-s) schedule of reinforcement. Twelve weeks after training began (age 23 weeks), they received one or three high-dose METH regimens. Each regimen consisted of four injections of 15 mg/kg, at 2-h intervals. Each regimen was separated by 7 weeks. A second group received METH treatment at age 23 weeks, but behavioral training was not initiated until the rats reached age 60 weeks. A third group received METH treatment without behavioral training. DRL behavior showed mild impairments 3 to 18 weeks after the onset of treatment; the impairments did not persist into middle age. At age 70 weeks, serotonin concentrations were decreased in somatosensory cortex, occipital cortex, and hippocampus but not in other subcortical structures. Serotonin tissue concentrations were enhanced in septum and striatum but only in rats receiving three regimens and behavioral training. Dopamine was not depleted at age 70 weeks. In three additional groups, one, two, or three METH regimens were administered, and tissue concentrations were measured 6 weeks after the last treatment (corresponding to the times of the behavioral test blocks in the DRL experiments). Serotonin depletions were noted in cortex, hippocampus, amygdala, and striatum but not in septum, hypothalamus, nucleus accumbens/olfactory tubercle, or ventral midbrain. Dopamine was decreased in striatum and septum but not in nucleus accumbens/olfactory tubercle, amygdala, hypothalamus, or ventral midbrain. DRL 72-s schedule impairments are attributed to serotonin depletions. Three METH regimens did not result in greater behavioral or neurochemical deficits than one regimen.

  19. Differential responsiveness to contractile agents of isolated smooth muscle cells from human colons as a function of age and inflammation.

    PubMed

    Boyer, J C; Guitton, C; Pignodel, C; Cuq, P; Moussu, P; Pouderoux, P; Christen, M O; Balmes, J L; Bali, J P

    1997-11-01

    To study the involvement of age and inflammation in motor colonic activity in man, contractile responses to CCK, carbachol, and KCl of isolated colonic smooth muscle cells (SMC) from normal and inflamed human colons were evaluated; the incidence of sex and smoking on contraction was also analyzed. Contractile responses to the three agonists were significantly lower in tissues with a low degree of inflammation than in tissues with high level of inflammation or normal tissues. This reduction in cell responsiveness appears to be nonspecific and nonreceptor mediated. A positive correlation of the contractile responses to the three stimulants with the age of patients was observed. In contrast, no association was found between sex, smoking, and cell contraction. In conclusion, contractions of SMC due to CCK, carbachol, and KCl were significantly modified during life; inflammation of the colon led to a loss of SMC responsiveness.

  20. Differential effects of aging, drinking and exercise on serum cholesterol levels dependent on the PPARA-V227A polymorphism.

    PubMed

    Naito, Hisao; Kamijima, Michihiro; Yamanoshita, Osamu; Nakahara, Ai; Katoh, Takahiko; Tanaka, Naoki; Aoyama, Toshifumi; Gonzalez, Frank J; Nakajima, Tamie

    2007-09-01

    Peroxisome proliferator-activated receptor alpha (PPARA alpha) plays a pivotal role in lipid metabolism. Our previous study reported that PPARA-V227A was a major polymorphism in Japanese, which was associated with markedly lower serum total cholesterol (TC) levels, which were significantly affected by alcohol drinking compared to subjects with the wild-type (PPARA-WT) allele. However, serum lipids are also associated with aging and exercise frequency. The objective of the present study was to evaluate the relationship between PPARA-V227A and these factors. Genetic analysis of the polymorphism was performed in 1058 Japanese men and 281 women, and the relationship with aging, drinking and exercise on serum lipids was analyzed in 989 men and 245 women after exclusion criteria had been applied. In men, drinking increased high-density lipoprotein cholesterol (HDL-C) levels in both PPARA-WT and A227 carriers, but to a significantly higher degree in the latter. In women, TC and low-density lipoprotein cholesterol (LDL-C) levels in the A227 carriers drinking at least once a week were significantly higher than in PPARA-WT carriers. TC and LDL-C levels in males with PPARA-WT increased with aging regardless of drinking habit, while LDL-C levels in the A227 drinking carriers were significantly lower in 45-yr-old or older subjects than in 35- to 45-yr-olds. In addition, no effect of exercising was observed in the A227 carriers, while increase in the HDL-C of the PPARA-WT carriers was exercise frequency dependent. These results suggest that the influence of drinking, aging or exercise on TC, LDL-C and HDL-C levels in the A227 carriers may be different from those in the PPARA-WT subjects.