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Sample records for activity key words

  1. Zum Gebrauch von Key Words im Englischunterricht (On the Use of Key Words in Teaching English)

    ERIC Educational Resources Information Center

    Bliemel, Willibald

    1975-01-01

    Discusses using key words as carriers of meaning for sentences, offering sample sentences in the fields of (1) dictation and guided narration, (2) structural pattern drills, (3) spoken dialog, and (4) silent reading. Here key words are important in deducing the meaning of new words. (Text is in German.) (IFS/WGA)

  2. "Journal of Geography" Key Words: Trends and Recommendations

    ERIC Educational Resources Information Center

    Mitchell, Jerry T.; Brysch, Carmen P.; Collins, Larianne

    2015-01-01

    The "Journal of Geography" has used key words since 1990 to help readers and researchers seek out work of particular interest. Key words generally supplement article titles and are hopefully chosen with care. The focus of this article is the "Journal of Geography" key word, its presence, timing, and frequency. Using a…

  3. A Problem-Solving Alternative to Using Key Words

    ERIC Educational Resources Information Center

    Clement, Lisa L.; Bernhard, Jamal Z.

    2005-01-01

    This article describes the pitfalls of using key words to support students when problem solving, and provides an alternative way (quantitative analysis) to support students' sense-making. (Contains 1 table and 2 figures.)

  4. The Activation of Embedded Words in Spoken Word Recognition.

    PubMed

    Zhang, Xujin; Samuel, Arthur G

    2015-01-01

    The current study investigated how listeners understand English words that have shorter words embedded in them. A series of auditory-auditory priming experiments assessed the activation of six types of embedded words (2 embedded positions × 3 embedded proportions) under different listening conditions. Facilitation of lexical decision responses to targets (e.g., pig) associated with words embedded in primes (e.g., hamster) indexed activation of the embedded words (e.g., ham). When the listening conditions were optimal, isolated embedded words (e.g., ham) primed their targets in all six conditions (Experiment 1a). Within carrier words (e.g., hamster), the same set of embedded words produced priming only when they were at the beginning or comprised a large proportion of the carrier word (Experiment 1b). When the listening conditions were made suboptimal by expanding or compressing the primes, significant priming was found for isolated embedded words (Experiment 2a), but no priming was produced when the carrier words were compressed/expanded (Experiment 2b). Similarly, priming was eliminated when the carrier words were presented with one segment replaced by noise (Experiment 3). When cognitive load was imposed, priming for embedded words was again found when they were presented in isolation (Experiment 4a), but not when they were embedded in the carrier words (Experiment 4b). The results suggest that both embedded position and proportion play important roles in the activation of embedded words, but that such activation only occurs under unusually good listening conditions.

  5. The Activation of Embedded Words in Spoken Word Recognition

    PubMed Central

    Zhang, Xujin; Samuel, Arthur G.

    2015-01-01

    The current study investigated how listeners understand English words that have shorter words embedded in them. A series of auditory-auditory priming experiments assessed the activation of six types of embedded words (2 embedded positions × 3 embedded proportions) under different listening conditions. Facilitation of lexical decision responses to targets (e.g., pig) associated with words embedded in primes (e.g., hamster) indexed activation of the embedded words (e.g., ham). When the listening conditions were optimal, isolated embedded words (e.g., ham) primed their targets in all six conditions (Experiment 1a). Within carrier words (e.g., hamster), the same set of embedded words produced priming only when they were at the beginning or comprised a large proportion of the carrier word (Experiment 1b). When the listening conditions were made suboptimal by expanding or compressing the primes, significant priming was found for isolated embedded words (Experiment 2a), but no priming was produced when the carrier words were compressed/expanded (Experiment 2b). Similarly, priming was eliminated when the carrier words were presented with one segment replaced by noise (Experiment 3). When cognitive load was imposed, priming for embedded words was again found when they were presented in isolation (Experiment 4a), but not when they were embedded in the carrier words (Experiment 4b). The results suggest that both embedded position and proportion play important roles in the activation of embedded words, but that such activation only occurs under unusually good listening conditions. PMID:25593407

  6. Key Words in Instruction. WebQuests

    ERIC Educational Resources Information Center

    Lamb, Annette

    2004-01-01

    In the mid-1990s, educators began exploring ways to make effective use of the vast information resources that were rapidly emerging on the Internet. Rather than using these new Web-based materials for low-level scavenger-hunt types of activities, school library media specialists sought ways to promote higher-order thinking through authentic…

  7. Which Words Are Activated during Bilingual Word Production?

    ERIC Educational Resources Information Center

    Colome, Angels; Miozzo, Michele

    2010-01-01

    Whether words are or are not activated within the lexicon of the nonused language is an important question for accounts of bilingual word production. Prior studies have not led to conclusive results, either because alternative accounts could be proposed for their findings or because activation could have been artificially induced by the…

  8. Processing of Color Words Activates Color Representations

    ERIC Educational Resources Information Center

    Richter, Tobias; Zwaan, Rolf A.

    2009-01-01

    Two experiments were conducted to investigate whether color representations are routinely activated when color words are processed. Congruency effects of colors and color words were observed in both directions. Lexical decisions on color words were faster when preceding colors matched the color named by the word. Color-discrimination responses…

  9. 2015: "key word" for wound care business success.

    PubMed

    Schaum, Kathleen D

    2015-01-01

    Wound care professionals should consider all this attention to the key word documentation as your 2015 "heads-up." You should conduct a self-audit and request an external audit of your own documentation against all the regulations, LCDs, Policy Articles, newsletters, and educational programs that CMS and your MACs are providing. You should also embrace the questioning and assistance, pertaining to your documentation, which you may receive from your coders and billers. These coding and billing professionals should be your "best friends" to help you improve your clinical documentation as soon as possible. You cannot afford to be one of the professionals who are requested to repay for services you actually provided just because you did not take the time to document your excellent wound care work.

  10. Functional Specificity of the Visual Word Form Area: General Activation for Words and Symbols but Specific Network Activation for Words

    ERIC Educational Resources Information Center

    Reinke, Karen; Fernandes, Myra; Schwindt, Graeme; O'Craven, Kathleen; Grady, Cheryl L.

    2008-01-01

    The functional specificity of the brain region known as the Visual Word Form Area (VWFA) was examined using fMRI. We explored whether this area serves a general role in processing symbolic stimuli, rather than being selective for the processing of words. Brain activity was measured during a visual 1-back task to English words, meaningful symbols…

  11. Activation of words with phonological overlap

    PubMed Central

    Friedrich, Claudia K.; Felder, Verena; Lahiri, Aditi; Eulitz, Carsten

    2013-01-01

    Multiple lexical representations overlapping with the input (cohort neighbors) are temporarily activated in the listener's mental lexicon when speech unfolds in time. Activation for cohort neighbors appears to rapidly decline as soon as there is mismatch with the input. However, it is a matter of debate whether or not they are completely excluded from further processing. We recorded behavioral data and event-related brain potentials (ERPs) in auditory-visual word onset priming during a lexical decision task. As primes we used the first two syllables of spoken German words. In a carrier word condition, the primes were extracted from spoken versions of the target words (ano-ANORAK “anorak”). In a cohort neighbor condition, the primes were taken from words that overlap with the target word up to the second nucleus (ana—taken from ANANAS “pineapple”). Relative to a control condition, where primes and targets were unrelated, lexical decision responses for cohort neighbors were delayed. This reveals that cohort neighbors are disfavored by the decision processes at the behavioral front end. In contrast, left-anterior ERPs reflected long-lasting facilitated processing of cohort neighbors. We interpret these results as evidence for extended parallel processing of cohort neighbors. That is, in parallel to the preparation and elicitation of delayed lexical decision responses to cohort neighbors, aspects of the processing system appear to keep track of those less efficient word candidates. PMID:24009593

  12. 40 CFR 355.61 - How are key words in this part defined?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 28 2014-07-01 2014-07-01 false How are key words in this part defined... Provisions § 355.61 How are key words in this part defined? Animal waste means manure (feces, urine, and.... Environment includes water, air, and land and the interrelationship that exists among and between water,...

  13. 40 CFR 355.61 - How are key words in this part defined?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Provisions § 355.61 How are key words in this part defined? Animal waste means manure (feces, urine, and other excrement produced by livestock), digestive emissions, and urea. The definition includes animal... 40 Protection of Environment 29 2012-07-01 2012-07-01 false How are key words in this part...

  14. Fluency: A Key Link between Word Identification and Comprehension

    ERIC Educational Resources Information Center

    Bashir, Anthony S.; Hook, Pamela E.

    2009-01-01

    Purpose: The purpose of this article is to respond to A. G. Kamhi's (2007) challenge to consider two points of view on reading--the broad and the narrow. Each point of view includes a component of the reading process; namely, comprehension and word recognition. Taken separately, each point of view is insufficient for our understanding of the…

  15. Patience: A Key Word when Talking with Teachers and Administrators

    ERIC Educational Resources Information Center

    McGee, Christy D.

    2012-01-01

    Summer activities have grown old. Going swimming has lost its allure, and boredom has set in. No matter how well parents have planned interesting and educational activities for the summer months or how much they have enjoyed the freedom from stricter schedules and more rigid bedtimes, it is time to transition back to the routines of the school…

  16. Beginning Readers Activate Semantics from Sub-Word Orthography

    ERIC Educational Resources Information Center

    Nation, Kate; Cocksey, Joanne

    2009-01-01

    Two experiments assessed whether 7-year-old children activate semantic information from sub-word orthography. Children made category decisions to visually-presented words, some of which contained an embedded word (e.g., "hip" in s"hip"). In Experiment 1 children were slower and less accurate to classify words if they contained an embedded word…

  17. 40 CFR 355.61 - How are key words in this part defined?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Provisions § 355.61 How are key words in this part defined? Animal waste means manure (feces, urine, and other excrement produced by livestock), digestive emissions, and urea. The definition includes animal... animal waste. CERCLA means the Comprehensive Environmental Response, Compensation and Liability Act...

  18. How Can Book Reading Close the Word Gap? Five Key Practices from Research

    ERIC Educational Resources Information Center

    Snell, Emily K.; Hindman, Annemarie H.; Wasik, Barbara A.

    2015-01-01

    Vocabulary development is critical for children's ability to learn to read and their success at school. Vocabulary has also been identified as a key factor in the achievement gap, with children from low-income families knowing significantly fewer words when they enter school. Although book reading has long been celebrated as an effective way for…

  19. Gender activation in transparent and opaque words.

    PubMed

    Urrutia, Mabel; Domínguez, Alberto; Alvarez, Carlos J

    2009-02-01

    Two reaction time experiments were carried out to examine the morphological gender processing of Spanish words that were either transparent -that is, ending in o/a (e.g., banco - bank)-or opaque-that is, without superficial gender marking (e.g., virtud - virtue). In Experiment 1, participants categorized the gender of a transparent gender target preceded by a derived word of the same gender (e.g., banquillo-dock, masculine) or of different gender (e.g., banqueta-stool, feminine). A negative priming gender effect indicates the use of strategic-attentional mechanisms to decide the gender of the target, but also automatic computation of the prime gender. Experiment 2 used a lexical decision task with the stimuli of Experiment 1 in addition to opaque gender words. The results show longer reaction times for transparent gender words with regard to opaque items. This effect was possibly due to the lexical requirements of the task: lexical decision, and also because transparent words are morphologically more complex than opaque words. Finally, in both experiments, there was negative priming: when prime and target were of the same gender, reaction times were longer. This effect indicates that participants cannot ignore the gender of the prime when they respond to the target.

  20. Elevating Baseline Activation Does Not Facilitate Reading of Unattended Words

    NASA Technical Reports Server (NTRS)

    Lien, Mei-Ching; Kouchi, Scott; Ruthruff, Eric; Lachter, Joel B.

    2009-01-01

    Previous studies have disagreed the extent to which people extract meaning from words presented outside the focus of spatial attention. The present study, examined a possible explanation for such discrepancies, inspired by attenuation theory: unattended words can be read more automatically when they have a high baseline level of activation (e.g., due to frequent repetition or due to being expected in a given context). We presented a brief prime word in lowercase, followed by a target word in uppercase. Participants indicated whether the target word belonged to a particular category (e.g., "sport"). When we drew attention to the prime word using a visual cue, the prime produced substantial priming effects on target responses (i.e., faster responses when the prime and target words were identical or from the same category than when they belonged to different categories). When prime words were not attended, however, they produced no priming effects. This finding replicated even when there were only 4 words, each repeated 160 times during the experiment. Even with a very high baseline level of activation, it appears that very little word processing is possible without spatial attention.

  1. Tempting food words activate eating simulations

    PubMed Central

    Papies, Esther K.

    2013-01-01

    This study shows that tempting food words activate simulations of eating the food, including simulations of the taste and texture of the food, simulations of eating situations, and simulations of hedonic enjoyment. In a feature listing task, participants generated features that are typically true of four tempting foods (e.g., chips) and four neutral foods (e.g., rice). The resulting features were coded as features of eating simulations if they referred to the taste, texture, and temperature of the food (e.g., “crunchy”; “sticky”), to situations of eating the food (e.g., “movie”; “good for Wok dishes”), and to the hedonic experience when eating the food (e.g., “tasty”). Based on the grounded cognition perspective, it was predicted that tempting foods are more likely to be represented in terms of actually eating them, so that participants would list more features referring to eating simulations for tempting than for neutral foods. Confirming this hypothesis, results showed that eating simulation features constituted 53% of the features for tempting food, and 26% of the features for neutral food. Visual features, in contrast, were mentioned more often for neutral foods (45%) than for tempting foods (19%). Exploratory analyses revealed that the proportion of eating simulation features for tempting foods was positively correlated with perceived attractiveness of the foods, and negatively with participants’ dieting concerns, suggesting that eating simulations may depend on individuals’ goals with regard to eating. These findings are discussed with regard to their implications for understanding the processes guiding eating behavior, and for interventions designed to reduce the consumption of attractive, unhealthy food. PMID:24298263

  2. Picturing words? Sensorimotor cortex activation for printed words in child and adult readers.

    PubMed

    Dekker, Tessa M; Mareschal, Denis; Johnson, Mark H; Sereno, Martin I

    2014-12-01

    Learning to read involves associating abstract visual shapes with familiar meanings. Embodiment theories suggest that word meaning is at least partially represented in distributed sensorimotor networks in the brain (Barsalou, 2008; Pulvermueller, 2013). We explored how reading comprehension develops by tracking when and how printed words start activating these "semantic" sensorimotor representations as children learn to read. Adults and children aged 7-10 years showed clear category-specific cortical specialization for tool versus animal pictures during a one-back categorisation task. Thus, sensorimotor representations for these categories were in place at all ages. However, co-activation of these same brain regions by the visual objects' written names was only present in adults, even though all children could read and comprehend all presented words, showed adult-like task performance, and older children were proficient readers. It thus takes years of training and expert reading skill before spontaneous processing of printed words' sensorimotor meanings develops in childhood.

  3. Automatic Activation of Orthography in Spoken Word Recognition: Pseudohomograph Priming

    ERIC Educational Resources Information Center

    Taft, Marcus; Castles, Anne; Davis, Chris; Lazendic, Goran; Nguyen-Hoan, Minh

    2008-01-01

    There is increasing evidence that orthographic information has an impact on spoken word processing. However, much of this evidence comes from tasks that are subject to strategic effects. In the three experiments reported here, we examined activation of orthographic information during spoken word processing within a paradigm that is unlikely to…

  4. Decoding and disrupting left midfusiform gyrus activity during word reading

    PubMed Central

    Hirshorn, Elizabeth A.; Ward, Michael J.; Fiez, Julie A.; Ghuman, Avniel Singh

    2016-01-01

    The nature of the visual representation for words has been fiercely debated for over 150 y. We used direct brain stimulation, pre- and postsurgical behavioral measures, and intracranial electroencephalography to provide support for, and elaborate upon, the visual word form hypothesis. This hypothesis states that activity in the left midfusiform gyrus (lmFG) reflects visually organized information about words and word parts. In patients with electrodes placed directly in their lmFG, we found that disrupting lmFG activity through stimulation, and later surgical resection in one of the patients, led to impaired perception of whole words and letters. Furthermore, using machine-learning methods to analyze the electrophysiological data from these electrodes, we found that information contained in early lmFG activity was consistent with an orthographic similarity space. Finally, the lmFG contributed to at least two distinguishable stages of word processing, an early stage that reflects gist-level visual representation sensitive to orthographic statistics, and a later stage that reflects more precise representation sufficient for the individuation of orthographic word forms. These results provide strong support for the visual word form hypothesis and demonstrate that across time the lmFG is involved in multiple stages of orthographic representation. PMID:27325763

  5. Differential Processing for Actively Ignored Pictures and Words

    PubMed Central

    Ciraolo, Margeaux

    2017-01-01

    Previous work suggests that, when attended, pictures may be processed more readily than words. The current study extends this research to assess potential differences in processing between these stimulus types when they are actively ignored. In a dual-task paradigm, facilitated recognition for previously ignored words was found provided that they appeared frequently with an attended target. When adapting the same paradigm here, previously unattended pictures were recognized at high rates regardless of how they were paired with items during the primary task, whereas unattended words were later recognized at higher rates only if they had previously been aligned with primary task targets. Implicit learning effects obtained by aligning unattended items with attended task-targets may apply only to conceptually abstract stimulus types, such as words. Pictures, on the other hand, may maintain direct access to semantic information, and are therefore processed more readily than words, even when being actively ignored. PMID:28122022

  6. Assessing language skills in adult key word signers with intellectual disabilities: Insights from sign linguistics.

    PubMed

    Grove, Nicola; Woll, Bencie

    2017-03-01

    Manual signing is one of the most widely used approaches to support the communication and language skills of children and adults who have intellectual or developmental disabilities, and problems with communication in spoken language. A recent series of papers reporting findings from this population raises critical issues for professionals in the assessment of multimodal language skills of key word signers. Approaches to assessment will differ depending on whether key word signing (KWS) is viewed as discrete from, or related to, natural sign languages. Two available assessments from these different perspectives are compared. Procedures appropriate to the assessment of sign language production are recommended as a valuable addition to the clinician's toolkit. Sign and speech need to be viewed as multimodal, complementary communicative endeavours, rather than as polarities. Whilst narrative has been shown to be a fruitful context for eliciting language samples, assessments for adult users should be designed to suit the strengths, needs and values of adult signers with intellectual disabilities, using materials that are compatible with their life course stage rather than those designed for young children.

  7. The Activation of Embedded Words in Spoken Word Identification Is Robust but Constrained: Evidence from the Picture-Word Interference Paradigm

    ERIC Educational Resources Information Center

    Bowers, Jeffrey S.; Davis, Colin J.; Mattys, Sven L.; Damian, Markus F.; Hanley, Derek

    2009-01-01

    Three picture-word interference (PWI) experiments assessed the extent to which embedded subset words are activated during the identification of spoken superset words (e.g., "bone" in "trombone"). Participants named aloud pictures (e.g., "brain") while spoken distractors were presented. In the critical condition,…

  8. Topical video object discovery from key frames by modeling word co-occurrence prior.

    PubMed

    Zhao, Gangqiang; Yuan, Junsong; Hua, Gang; Yang, Jiong

    2015-12-01

    A topical video object refers to an object, that is, frequently highlighted in a video. It could be, e.g., the product logo and the leading actor/actress in a TV commercial. We propose a topic model that incorporates a word co-occurrence prior for efficient discovery of topical video objects from a set of key frames. Previous work using topic models, such as latent Dirichelet allocation (LDA), for video object discovery often takes a bag-of-visual-words representation, which ignored important co-occurrence information among the local features. We show that such data driven co-occurrence information from bottom-up can conveniently be incorporated in LDA with a Gaussian Markov prior, which combines top-down probabilistic topic modeling with bottom-up priors in a unified model. Our experiments on challenging videos demonstrate that the proposed approach can discover different types of topical objects despite variations in scale, view-point, color and lighting changes, or even partial occlusions. The efficacy of the co-occurrence prior is clearly demonstrated when compared with topic models without such priors.

  9. Making a Bigger Deal of the Smaller Words: Function Words and Other Key Items in Research Writing by Chinese Learners

    ERIC Educational Resources Information Center

    Lee, David Y. W.; Chen, Sylvia Xiao

    2009-01-01

    In many mainland Chinese universities, undergraduate students specializing in English language and applied linguistics are required to write a dissertation, in English, of about 5000 words exploring some aspect of original research. This is a task which is of considerable difficulty not only at the genre or discourse level but also at the…

  10. A computerized on-line key word indexing system for drug information retrieval.

    PubMed

    Sasich, L; Morris, H A

    1981-03-01

    The Idaho Drug Information Service has been in operation since 1972. During this time, five different files and manual methods of filing have evolved. As a result of confusion over indexing terms, information became lost within the filing systems, and the files fell into disuse. A reorganization of the files was undertaken in an attempt to develop a filing system that would be functional and efficient. Methods of manual filing are briefly reviewed. A computerized on-line key word indexing system for information storage and retrieval was initiated. The development and operation of the Drug Information Retrieval Terminal System (DIRTS) is described completely. At this time, DIRTS is fully operational. The system has eliminated the previous problems encountered with the manual filing systems, and user response has been good.

  11. Picturing words? Sensorimotor cortex activation for printed words in child and adult readers

    PubMed Central

    Dekker, Tessa M.; Mareschal, Denis; Johnson, Mark H.; Sereno, Martin I.

    2014-01-01

    Learning to read involves associating abstract visual shapes with familiar meanings. Embodiment theories suggest that word meaning is at least partially represented in distributed sensorimotor networks in the brain (Barsalou, 2008; Pulvermueller, 2013). We explored how reading comprehension develops by tracking when and how printed words start activating these “semantic” sensorimotor representations as children learn to read. Adults and children aged 7–10 years showed clear category-specific cortical specialization for tool versus animal pictures during a one-back categorisation task. Thus, sensorimotor representations for these categories were in place at all ages. However, co-activation of these same brain regions by the visual objects’ written names was only present in adults, even though all children could read and comprehend all presented words, showed adult-like task performance, and older children were proficient readers. It thus takes years of training and expert reading skill before spontaneous processing of printed words’ sensorimotor meanings develops in childhood. PMID:25463817

  12. Word Length and Lexical Activation: Longer Is Better

    ERIC Educational Resources Information Center

    Pitt, Mark A.; Samuel, Arthur G.

    2006-01-01

    Many models of spoken word recognition posit the existence of lexical and sublexical representations, with excitatory and inhibitory mechanisms used to affect the activation levels of such representations. Bottom-up evidence provides excitatory input, and inhibition from phonetically similar representations leads to lexical competition. In such a…

  13. Phonological Activation of Word Meanings in Grade 5 Readers

    ERIC Educational Resources Information Center

    Jared, Debra; Ashby, Jane; Agauas, Stephen J.; Levy, Betty Ann

    2016-01-01

    Three experiments examined the role of phonology in the activation of word meanings in Grade 5 students. In Experiment 1, homophone and spelling control errors were embedded in a story context and participants performed a proofreading task as they read for meaning. For both good and poor readers, more homophone errors went undetected than spelling…

  14. 40 CFR 370.3 - Which section contains the definitions of the key words used in this part?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 27 2010-07-01 2010-07-01 false Which section contains the definitions of the key words used in this part? 370.3 Section 370.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS...

  15. 40 CFR 355.3 - Which section contains the definitions of the key words used in this part?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 27 2010-07-01 2010-07-01 false Which section contains the definitions of the key words used in this part? 355.3 Section 355.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS...

  16. Investigating Peer Attitudes towards the Use of Key Word Signing by Children with Down Syndrome in Mainstream Schools

    ERIC Educational Resources Information Center

    Bowles, Caoimhe; Frizelle, Pauline

    2016-01-01

    Background: Lámh is a key word signing approach used in Ireland, which can support the communication needs of children with Down syndrome. However, the success of this approach in mainstream schools relies heavily on the attitudes of those within the school environment. To date, two studies have explored the attitudes of teaching staff towards the…

  17. How Do Deaf Children with and without Cochlear Implants Manage to Read Sentences: The Key Word Strategy

    ERIC Educational Resources Information Center

    Domínguez, Ana-Belén; Carrillo, María-Soledad; González, Virginia; Alegria, Jesús

    2016-01-01

    The aim of this study is to examine the mechanisms used by deaf children with and without cochlear implants (CIs) to read sentences and the linguistic bases (vocabulary and syntax) underlying those reading mechanisms. Previous studies have shown that deaf persons read sentences using the key word strategy (KWS), which consists of identifying some…

  18. Reduce, Reuse, Recycle: An ESL Textbook/Workbook [In Four Volumes]: (1) Teaching Guide; (2) Edition A. Key Vocabulary Words Translated into 6 Languages: Hmong, Laotian, Korean, Cambodian, Vietnamese, Chinese; (3) Edition B. Key Vocabulary Words Translated into 6 Languages: Spanish, Somali, Russian, Farsi, Bosnian, Arabic; (4) Edition C. Key Vocabulary Words Translated in 6 Languages: Spanish, Russian, Bosnian, Somali, Vietnamese, Hmong.

    ERIC Educational Resources Information Center

    LaRue, Charles

    Each of these three separately-published textbook/workbook editions on the topic of recycling presents key vocabulary words relating to this topic for English as a Second Language students in six languages. These books are designed to increase students' understanding of what the most typical local recycling rules are, why complying with them is…

  19. Orthographic representations in spoken word priming: no early automatic activation.

    PubMed

    Pattamadilok, Chotiga; Kolinsky, Régine; Ventura, Paulo; Radeau, Monique; Morais, José

    2007-01-01

    The current study investigated the modulation by orthographic knowledge of the final overlap phonological priming effect, contrasting spoken prime-target pairs with congruent spellings (e.g., 'carreau-bourreau', /karo/-/buro/) to pairs with incongruent spellings (e.g., 'zéro-bourreau', /zero/-/buro/). Using materials and designs aimed at reducing the impact of response biases or strategies, no orthographic congruency effect was found in shadowing, a speech recognition task that can be performed prelexically. In lexical decision, an orthographic effect occurred only when the processing environment reduced the prominence of phonological overlap and thus induced participants to rely on word spelling. Overall, the data do not support the assumption of early, automatic activation of orthographic representations during spoken word recognition.

  20. Key Contextual Features of Algebra Word Problems: A Theoretical Model and Review of the Literature.

    ERIC Educational Resources Information Center

    Nasser, Ramzi; Carifio, James

    One of the four algebra word problem structures found in K-12 textbooks is the propositional relation structure (Mayer, 1982). This type of problem asks students to establish equivalences between the variables or noun referents in the problem. The literature available indicates that students have inordinate difficulties, when trying to solve a…

  1. Left temporal alpha-band activity reflects single word intelligibility

    PubMed Central

    Becker, Robert; Pefkou, Maria; Michel, Christoph M.; Hervais-Adelman, Alexis G.

    2013-01-01

    The electroencephalographic (EEG) correlates of degraded speech perception have been explored in a number of recent studies. However, such investigations have often been inconclusive as to whether observed differences in brain responses between conditions result from different acoustic properties of more or less intelligible stimuli or whether they relate to cognitive processes implicated in comprehending challenging stimuli. In this study we used noise vocoding to spectrally degrade monosyllabic words in order to manipulate their intelligibility. We used spectral rotation to generate incomprehensible control conditions matched in terms of spectral detail. We recorded EEG from 14 volunteers who listened to a series of noise vocoded (NV) and noise-vocoded spectrally-rotated (rNV) words, while they carried out a detection task. We specifically sought components of the EEG response that showed an interaction between spectral rotation and spectral degradation. This reflects those aspects of the brain electrical response that are related to the intelligibility of acoustically degraded monosyllabic words, while controlling for spectral detail. An interaction between spectral complexity and rotation was apparent in both evoked and induced activity. Analyses of event-related potentials showed an interaction effect for a P300-like component at several centro-parietal electrodes. Time-frequency analysis of the EEG signal in the alpha-band revealed a monotonic increase in event-related desynchronization (ERD) for the NV but not the rNV stimuli in the alpha band at a left temporo-central electrode cluster from 420–560 ms reflecting a direct relationship between the strength of alpha-band ERD and intelligibility. By matching NV words with their incomprehensible rNV homologues, we reveal the spatiotemporal pattern of evoked and induced processes involved in degraded speech perception, largely uncontaminated by purely acoustic effects. PMID:24416001

  2. Increase in posterior alpha activity during rehearsal predicts successful long-term memory formation of word sequences.

    PubMed

    Meeuwissen, Esther B; Takashima, Atsuko; Fernández, Guillén; Jensen, Ole

    2011-12-01

    It is becoming increasingly clear that demanding cognitive tasks rely on an extended network engaging task-relevant areas and, importantly, disengaging task-irrelevant areas. Given that alpha activity (8-12 Hz) has been shown to reflect the disengagement of task-irrelevant regions in attention and working memory tasks, we here ask if alpha activity plays a related role for long-term memory formation. Subjects were instructed to encode and maintain the order of word sequences while the ongoing brain activity was recorded using magnetoencephalography (MEG). In each trial, three words were presented followed by a 3.4 s rehearsal interval. Considering the good temporal resolution of MEG this allowed us to investigate the word presentation and rehearsal interval separately. The sequences were grouped in trials where word order either could be tested immediately (working memory trials; WM) or later (LTM trials) according to instructions. Subjects were tested on their ability to retrieve the order of the three words. The data revealed that alpha power in parieto-occipital regions was lower during word presentation compared to rehearsal. Our key finding was that parieto-occipital alpha power during the rehearsal period was markedly stronger for successfully than unsuccessfully encoded LTM sequences. This subsequent memory effect demonstrates that high posterior alpha activity creates an optimal brain state for successful LTM formation possibly by actively reducing parieto-occipital activity that might interfere with sequence encoding.

  3. Implicit Statistical Learning in Language Processing: Word Predictability is the Key

    PubMed Central

    Conway, Christopher M.; Baurnschmidt, Althea; Huang, Sean; Pisoni, David B.

    2010-01-01

    Fundamental learning abilities related to the implicit encoding of sequential structure have been postulated to underlie language acquisition and processing. However, there is very little direct evidence to date supporting such a link between implicit statistical learning and language. In three experiments using novel methods of assessing implicit learning and language abilities, we show that sensitivity to sequential structure -- as measured by improvements to immediate memory span for structurally-consistent input sequences -- is significantly correlated with the ability to use knowledge of word predictability to aid speech perception under degraded listening conditions. Importantly, the association remained even after controlling for participant performance on other cognitive tasks, including short-term and working memory, intelligence, attention and inhibition, and vocabulary knowledge. Thus, the evidence suggests that implicit learning abilities are essential for acquiring long-term knowledge of the sequential structure of language -- i.e., knowledge of word predictability – and that individual differences on such abilities impact speech perception in everyday situations. These findings provide a new theoretical rationale linking basic learning phenomena to specific aspects of spoken language processing in adults, and may furthermore indicate new fruitful directions for investigating both typical and atypical language development. PMID:19922909

  4. Cross-Linguistic Activation in Bilingual Sentence Processing: The Role of Word Class Meaning

    ERIC Educational Resources Information Center

    Baten, Kristof; Hofman, Fabrice; Loeys, Tom

    2011-01-01

    This study investigates how categorial (word class) semantics influences cross-linguistic interactions when reading in L2. Previous homograph studies paid little attention to the possible influence of different word classes in the stimulus material on cross-linguistic activation. The present study examines the word recognition performance of…

  5. Modeling of Word Translation: Activation Flow from Concepts to Lexical Items

    ERIC Educational Resources Information Center

    Roelofs, Ardi; Dijkstra, Ton; Gerakaki, Svetlana

    2013-01-01

    Whereas most theoretical and computational models assume a continuous flow of activation from concepts to lexical items in spoken word production, one prominent model assumes that the mapping of concepts onto words happens in a discrete fashion (Bloem & La Heij, 2003). Semantic facilitation of context pictures on word translation has been taken to…

  6. Written distractor words influence brain activity during overt picture naming

    PubMed Central

    Diaz, Michele T.; Hogstrom, Larson J.; Zhuang, Jie; Voyvodic, James T.; Johnson, Micah A.; Camblin, C. Christine

    2014-01-01

    Language production requires multiple stages of processing (e.g., semantic retrieval, lexical selection), each of which may involve distinct brain regions. Distractor words can be combined with picture naming to examine factors that influence language production. Phonologically-related distractors have been found to speed picture naming (facilitation), while slower response times and decreased accuracy (interference) generally occur when a distractor is categorically related to the target image. However, other types of semantically-related distractors have been reported to produce a facilitative effect (e.g., associative, part-whole). The different pattern of results for different types of semantically-related distractors raises the question about how the nature of the semantic relation influences the effect of the distractor. To explore the nature of these semantic effects further, we used functional MRI to examine the influence of four types of written distractors on brain activation during overt picture naming. Distractors began with the same sound, were categorically-related, part of the object to be named, or were unrelated to the picture. Phonologically-related trials elicited greater activation than both semantic conditions (categorically-related and part-whole) in left insula and bilateral parietal cortex, regions that have been attributed to phonological aspects of production and encoding, respectively. Semantic conditions elicited greater activation than phonological trials in left posterior MTG, a region that has been linked to concept retrieval and semantic integration. Overall, the two semantic conditions did not differ substantially in their functional activation which suggests a similarity in the semantic demands and lexical competition across these two conditions. PMID:24715859

  7. Word Processors and Writing Activities for the Elementary Grades. A MicroSIFT Quarterly Report.

    ERIC Educational Resources Information Center

    Batey, Anne; Ricketts, Dick

    Intended to help educators choose the most appropriate word processing products for elementary school writing instruction, this report provides information about 12 word processor software products and 13 writing activity products. These products and the writing activities they use are as follows: (1) Bank Street Writer III (Activity Files,…

  8. I 5683 you: dialing phone numbers on cell phones activates key-concordant concepts.

    PubMed

    Topolinski, Sascha

    2011-03-01

    When people perform actions, effects associated with the actions are activated mentally, even if those effects are not apparent. This study tested whether sequences of simulations of virtual action effects can be integrated into a meaning of their own. Cell phones were used to test this hypothesis because pressing a key on a phone is habitually associated with both digits (dialing numbers) and letters (typing text messages). In Experiment 1, dialing digit sequences induced the meaning of words that share the same key sequence (e.g., 5683, LOVE). This occurred even though the letters were not labeled on the keypad, and participants were not aware of the digit-letter correspondences. In Experiment 2, subjects preferred dialing numbers implying positive words (e.g., 37326, DREAM) over dialing numbers implying negative words (e.g., 75463, SLIME). In Experiment 3, subjects preferred companies with phone numbers implying a company-related word (e.g., LOVE for a dating agency, CORPSE for a mortician) compared with companies with phone numbers implying a company-unrelated word.

  9. Evaluation of language and communication skills in adult key word signing users with intellectual disability: advantages of a narrative task.

    PubMed

    Meuris, Kristien; Maes, Bea; Zink, Inge

    2014-10-01

    The evaluation of language and communication skills in adults who use augmentative and alternative communication (AAC) in general and key word signing (KWS) in particular, can be an elaborate task. Besides being time-consuming and not very similar to natural communication, standard language tests often do not take AAC or KWS into account. Therefore, we developed a narrative task specifically for adults with intellectual disability (ID) who use KWS. The task was evaluated in a group of 40 adult KWS users. Outcome measures on the narrative task correlated significantly with measures of standard language and communication tests for verbal language, but not for use of manual signs. All narrative measures, for both verbal language and manual signing, correlated highly with similar measures from a conversation sample. The developed narrative task proved useful and valid to evaluate the language and communication skills of adults with ID taking into account both their verbal language and manual sign use.

  10. On the problem of non-zero word error rates for fixed-rate error correction codes in continuous variable quantum key distribution

    NASA Astrophysics Data System (ADS)

    Johnson, Sarah J.; Lance, Andrew M.; Ong, Lawrence; Shirvanimoghaddam, Mahyar; Ralph, T. C.; Symul, Thomas

    2017-02-01

    The maximum operational range of continuous variable quantum key distribution protocols has shown to be improved by employing high-efficiency forward error correction codes. Typically, the secret key rate model for such protocols is modified to account for the non-zero word error rate of such codes. In this paper, we demonstrate that this model is incorrect: firstly, we show by example that fixed-rate error correction codes, as currently defined, can exhibit efficiencies greater than unity. Secondly, we show that using this secret key model combined with greater than unity efficiency codes, implies that it is possible to achieve a positive secret key over an entanglement breaking channel—an impossible scenario. We then consider the secret key model from a post-selection perspective, and examine the implications for key rate if we constrain the forward error correction codes to operate at low word error rates.

  11. When deaf signers read English: do written words activate their sign translations?

    PubMed

    Morford, Jill P; Wilkinson, Erin; Villwock, Agnes; Piñar, Pilar; Kroll, Judith F

    2011-02-01

    Deaf bilinguals for whom American Sign Language (ASL) is the first language and English is the second language judged the semantic relatedness of word pairs in English. Critically, a subset of both the semantically related and unrelated word pairs were selected such that the translations of the two English words also had related forms in ASL. Word pairs that were semantically related were judged more quickly when the form of the ASL translation was also similar whereas word pairs that were semantically unrelated were judged more slowly when the form of the ASL translation was similar. A control group of hearing bilinguals without any knowledge of ASL produced an entirely different pattern of results. Taken together, these results constitute the first demonstration that deaf readers activate the ASL translations of written words under conditions in which the translation is neither present perceptually nor required to perform the task.

  12. Phonological and Semantic Activation in Reading Two-Kanji Compound Words.

    ERIC Educational Resources Information Center

    Morita, Aiko; Matsuda, Fumiko

    2000-01-01

    Examined whether phonological information was activated automatically in processing two kanji compound words. In one experiment, participants judged whether pairs of words were homophones, while others judged whether pairs were synonyms. In the second, participants were asked to make one of the two judgments, as in experiment one. Findings support…

  13. Brain activity of adolescents with high functioning autism in response to emotional words and facial emoticons.

    PubMed

    Han, Doug Hyun; Yoo, Hee Jeong; Kim, Bung Nyun; McMahon, William; Renshaw, Perry F

    2014-01-01

    Studies of social dysfunction in patients with autism spectrum disorder (ASD) have generally focused on the perception of emotional words and facial affect. Brain imaging studies have suggested that the fusiform gyrus is associated with both the comprehension of language and face recognition. We hypothesized that patients with ASD would have decreased ability to recognize affect via emotional words and facial emoticons, relative to healthy comparison subjects. In addition, we expected that this decreased ability would be associated with altered activity of the fusiform gyrus in patients with ASD. Ten male adolescents with ASDs and ten age and sex matched healthy comparison subjects were enrolled in this case-control study. The diagnosis of autism was further evaluated with the Autism Diagnostic Observation Schedule. Brain activity was assessed using functional magnetic resonance imaging (fMRI) in response to emotional words and facial emoticon presentation. Sixty emotional words (45 pleasant words +15 unpleasant words) were extracted from a report on Korean emotional terms and their underlying dimensions. Sixty emoticon faces (45 pleasant faces +15 unpleasant faces) were extracted and modified from on-line sites. Relative to healthy comparison subjects, patients with ASD have increased activation of fusiform gyrus in response to emotional aspects of words. In contrast, patients with ASD have decreased activation of fusiform gyrus in response to facial emoticons, relative to healthy comparison subjects. We suggest that patients with ASD are more familiar with word descriptions than facial expression as depictions of emotion.

  14. Evidence for an Activation Locus of the Word-Frequency Effect in Lexical Decision

    ERIC Educational Resources Information Center

    Allen, Philip A.; Smith, Albert F.; Lien, Mei-Ching; Grabbe, Jeremy; Murphy, Martin D.

    2005-01-01

    The authors report a lexical decision experiment designed to determine whether activation is the locus of the word-frequency effect. K. R. Paap and L. S. Johansen (1994) reported that word frequency did not affect lexical decisions when exposure durations were brief; they accounted for this by proposing that data-limited conditions prevented…

  15. Task-Dependent Modulations of Prefrontal and Hippocampal Activity during Intrinsic Word Production

    ERIC Educational Resources Information Center

    Whitney, Carin; Weis, Susanne; Krings, Timo; Huber, Walter; Grossman, Murray; Kircher, Tilo

    2009-01-01

    Functional imaging studies of single word production have consistently reported activation of the lateral prefrontal and cingulate cortex. Its contribution has been shown to be sensitive to task demands, which can be manipulated by the degree of response specification. Compared with classical verbal fluency, free word association relies less on…

  16. Learning Computers, Speaking English: Cooperative Activities for Learning English and Basic Word Processing.

    ERIC Educational Resources Information Center

    Quann, Steve; Satin, Diana

    This textbook leads high-beginning and intermediate English-as-a-Second-Language (ESL) students through cooperative computer-based activities that combine language learning with training in basic computer skills and word processing. Each unit concentrates on a basic concept of word processing while also focusing on a grammar topic. Skills are…

  17. Acquisition of Compound Words in Chinese-English Bilingual Children: Decomposition and Cross-Language Activation

    ERIC Educational Resources Information Center

    Cheng, Chenxi; Wang, Min; Perfetti, Charles A.

    2011-01-01

    This study investigated compound processing and cross-language activation in a group of Chinese-English bilingual children, and they were divided into four groups based on the language proficiency levels in their two languages. A lexical decision task was designed using compound words in both languages. The compound words in one language contained…

  18. A comparison of brain activity evoked by single content and function words: an fMRI investigation of implicit word processing.

    PubMed

    Diaz, Michele T; McCarthy, Gregory

    2009-07-28

    Content and function words have different roles in language and differ greatly in their semantic content. Although previous research has suggested that these different roles may be mediated by different neural substrates, the neuroimaging literature on this topic is particularly scant. Moreover, fMRI studies that have investigated differences between content and function words have utilized tasks that focus the subjects' attention on the differences between these word types. It is possible, then, that task-related differences in attention, working memory, and decision-making contribute to the differential patterns of activation observed. Here, subjects were engaged in a continuous working memory cover task while single, task-irrelevant content and function words were infrequently and irregularly presented. Nonword letter strings were displayed in black font at a fast rate (2/s). Subjects were required to either remember or retrieve occasional nonwords that were presented in colored fonts. Incidental and irrelevant to the memory task, content and function words were interspersed among nonwords at intervals of 12 to 15 s. Both word types strongly activated temporal-parietal cortex, middle and anterior temporal cortex, inferior frontal gyrus, parahippocampal gyrus, and orbital frontal cortex. Activations were more extensive in the left hemisphere. Content words elicited greater activation than function words in middle and anterior temporal cortex, a sub-region of orbital frontal cortex, and the parahippocampal region. Words also evoked extensive deactivation, most notably in brain regions previously associated with working memory and attention.

  19. Prominences: The Key to Understanding Solar Activity

    NASA Technical Reports Server (NTRS)

    Karpen, Judy T.

    2011-01-01

    Prominences are spectacular manifestations of both quiescent and eruptive solar activity. The largest examples can be seen with the naked eye during eclipses, making prominences among the first solar features to be described and catalogued. Steady improvements in temporal and spatial resolution from both ground- and space-based instruments have led us to recognize how complex and dynamic these majestic structures really are. Their distinguishing characteristics - cool knots and threads suspended in the hot corona, alignment along inversion lines in the photospheric magnetic field within highly sheared filament channels, and a tendency to disappear through eruption - offer vital clues as to their origin and dynamic evolution. Interpreting these clues has proven to be contentious, however, leading to fundamentally different models that address the basic questions: What is the magnetic structure supporting prominences, and how does so much cool, dense plasma appear in the corona? Despite centuries of increasingly detailed observations, the magnetic and plasma structures in prominences are poorly known. Routine measurements of the vector magnetic field in and around prominences have become possible only recently, while long-term monitoring of the underlying filament-channel formation process also remains scarce. The process responsible for prominence mass is equally difficult to establish, although we have long known that the chromosphere is the only plausible source. As I will discuss, however, the motions and locations of prominence material can be used to trace the coronal field, thus defining the magnetic origins of solar eruptions. A combination of observations, theory, and numerical modeling must be used to determine whether any of the competing theories accurately represents the physics of prominences. I will discuss the criteria for a successful prominence model, compare the leading models, and present in detail one promising, comprehensive scenario for

  20. Investigation of Pre-Service English Language Teachers' Cognitive Structures about Some Key Concepts in Approaches and Methods in Language Teaching Course through Word Association Test

    ERIC Educational Resources Information Center

    Ersanli, Ceylan Yangin

    2016-01-01

    This study aims to map the cognitive structure of pre-service English language (EL) teachers about three key concepts related to approaches and methods in language teaching so as to discover their learning process and misconceptions. The study involves both qualitative and quantitative data. The researcher administrated a Word Association Test…

  1. Lip EMG activity during vowel production in apraxia of speech: phrase context and word length effects.

    PubMed

    Hough, M S; Klich, R J

    1998-08-01

    This investigation examined the timing relationships of EMG activity underlying vowel production in 2 normal individuals and in 2 individuals with marked-to-severe apraxia of speech of approximately two-and-one-half years duration. The timing of lip muscle activity was investigated in monosyllabic words embedded in phrases and in syllable word stems as a function of changes in word length. Specifically, the onset and offset of EMG activity of lip muscles used for production of /u/ in the monosyllables and word stems were examined. The results revealed that the relative amounts of time devoted to onset and offset of EMG activity for lip rounding are disorganized in apraxia of speech. Word length appeared to affect the timing of the onset of muscle activity for both the normal speakers and the speakers with apraxia of speech. Word length also influenced the offset of muscle activity, but its effect was less systematic for the speakers with apraxia of speech. The findings suggest that termination of EMG activity may be at least as disturbed as the initiation of EMG activity in apraxia of speech.

  2. The left occipitotemporal cortex does not show preferential activity for words.

    PubMed

    Vogel, Alecia C; Petersen, Steven E; Schlaggar, Bradley L

    2012-12-01

    Regions in left occipitotemporal (OT) cortex, including the putative visual word form area, are among the most commonly activated in imaging studies of single-word reading. It remains unclear whether this part of the brain is more precisely characterized as specialized for words and/or letters or contains more general-use visual regions having properties useful for processing word stimuli, among others. In Analysis 1, we found no evidence of greater activity in left OT regions for words or letter strings relative to other high-spatial frequency high-contrast stimuli, including line drawings and Amharic strings (which constitute the Ethiopian writing system). In Analysis 2, we further investigated processing characteristics of OT cortex potentially useful in reading. Analysis 2 showed that a specific part of OT cortex 1) is responsive to visual feature complexity, measured by the number of strokes forming groups of letters or Amharic strings and 2) processes learned combinations of characters, such as those in words and pseudowords, as groups but does not do so in consonant and Amharic strings. Together, these results indicate that while regions of left OT cortex are not specialized for words, at least part of OT cortex has properties particularly useful for processing words and letters.

  3. Orthographic Activation in L2 Spoken Word Recognition Depends on Proficiency: Evidence from Eye-Tracking

    PubMed Central

    Veivo, Outi; Järvikivi, Juhani; Porretta, Vincent; Hyönä, Jukka

    2016-01-01

    The use of orthographic and phonological information in spoken word recognition was studied in a visual world task where L1 Finnish learners of L2 French (n = 64) and L1 French native speakers (n = 24) were asked to match spoken word forms with printed words while their eye movements were recorded. In Experiment 1, French target words were contrasted with competitors having a longer ( vs. ) or a shorter word initial phonological overlap ( vs. ) and an identical orthographic overlap. In Experiment 2, target words were contrasted with competitors of either longer ( vs. ) or shorter word initial orthographic overlap ( vs. ) and of an identical phonological overlap. A general phonological effect was observed in the L2 listener group but not in the L1 control group. No general orthographic effects were observed in the L2 or L1 groups, but a significant effect of proficiency was observed for orthographic overlap over time: higher proficiency L2 listeners used also orthographic information in the matching task in a time-window from 400 to 700 ms, whereas no such effect was observed for lower proficiency listeners. These results suggest that the activation of orthographic information in L2 spoken word recognition depends on proficiency in L2. PMID:27512381

  4. A Vocabulary Flood: Making Words "Sticky" with Computer-Response Activities

    ERIC Educational Resources Information Center

    Labbo, Linda D.; Love, Mary S.; Ryan, Tammy

    2007-01-01

    Children's literature is a primary source for introducing young children to new words at home and at school, and children's early vocabulary knowledge is a key component of oral language, which is essential for comprehension. This column is focused on children from low socioeconomic backgrounds who frequently find themselves in a vocabulary…

  5. Broca's region and Visual Word Form Area activation differ during a predictive Stroop task.

    PubMed

    Wallentin, Mikkel; Gravholt, Claus Højbjerg; Skakkebæk, Anne

    2015-12-01

    Competing theories attempt to explain the function of Broca's area in single word processing. Studies have found the region to be more active during processing of pseudo words than real words and during infrequent words relative to frequent words and during Stroop (incongruent) color words compared to Non-Stroop (congruent) words. Two related theories explain these findings as reflecting either "cognitive control" processing in the face of conflicting input or a linguistic prediction error signal, based on a predictive coding approach. The latter implies that processing cost refers to violations of expectations based on the statistical distributions of input. In this fMRI experiment we attempted to disentangle single word processing cost originating from cognitive conflict and that stemming from predictive expectation violation. Participants (N = 49) responded to whether the words "GREEN" or "RED" were displayed in green or red (incongruent vs congruent colors). One of the colors, however, was presented three times as often as the other, making it possible to study both congruency and frequency effects independently. Auditory stimuli saying "GREEN" or "RED" had the same distribution, making it possible to study frequency effects across modalities. We found significant behavioral effects of both incongruency and frequency. A significant effect (p < .05 FWE) of incongruency was found in Broca's region, but no effect of frequency was observed and no interaction. Conjoined effects of incongruency and frequency were found in parietal regions as well as in the Visual Word Form Area (VWFA). No interaction between perceptual modality and frequency was found in VWFA suggesting that the region is not strictly visual. These findings speak against a strong version of the prediction error processing hypothesis in Broca's region. They support the idea that prediction error processes in the intermediate timeframe are allocated to more posterior parts of the brain.

  6. Left ventral occipitotemporal activation during orthographic and semantic processing of auditory words.

    PubMed

    Ludersdorfer, Philipp; Wimmer, Heinz; Richlan, Fabio; Schurz, Matthias; Hutzler, Florian; Kronbichler, Martin

    2016-01-01

    The present fMRI study investigated the hypothesis that activation of the left ventral occipitotemporal cortex (vOT) in response to auditory words can be attributed to lexical orthographic rather than lexico-semantic processing. To this end, we presented auditory words in both an orthographic ("three or four letter word?") and a semantic ("living or nonliving?") task. In addition, a auditory control condition presented tones in a pitch evaluation task. The results showed that the left vOT exhibited higher activation for orthographic relative to semantic processing of auditory words with a peak in the posterior part of vOT. Comparisons to the auditory control condition revealed that orthographic processing of auditory words elicited activation in a large vOT cluster. In contrast, activation for semantic processing was only weak and restricted to the middle part vOT. We interpret our findings as speaking for orthographic processing in left vOT. In particular, we suggest that activation in left middle vOT can be attributed to accessing orthographic whole-word representations. While activation of such representations was experimentally ascertained in the orthographic task, it might have also occurred automatically in the semantic task. Activation in the more posterior vOT region, on the other hand, may reflect the generation of explicit images of word-specific letter sequences required by the orthographic but not the semantic task. In addition, based on cross-modal suppression, the finding of marked deactivations in response to the auditory tones is taken to reflect the visual nature of representations and processes in left vOT.

  7. Locality and Word Order in Active Dependency Formation in Bangla

    PubMed Central

    Chacón, Dustin A.; Imtiaz, Mashrur; Dasgupta, Shirsho; Murshed, Sikder M.; Dan, Mina; Phillips, Colin

    2016-01-01

    Research on filler-gap dependencies has revealed that there are constraints on possible gap sites, and that real-time sentence processing is sensitive to these constraints. This work has shown that comprehenders have preferences for potential gap sites, and immediately detect when these preferences are not met. However, neither the mechanisms that select preferred gap sites nor the mechanisms used to detect whether these preferences are met are well-understood. In this paper, we report on three experiments in Bangla, a language in which gaps may occur in either a pre-verbal embedded clause or a post-verbal embedded clause. This word order variation allows us to manipulate whether the first gap linearly available is contained in the same clause as the filler, which allows us to dissociate structural locality from linear locality. In Experiment 1, an untimed ambiguity resolution task, we found a global bias to resolve a filler-gap dependency with the first gap linearly available, regardless of structural hierarchy. In Experiments 2 and 3, which use the filled-gap paradigm, we found sensitivity to disruption only when the blocked gap site is both structurally and linearly local, i.e., the filler and the gap site are contained in the same clause. This suggests that comprehenders may not show sensitivity to the disruption of all preferred gap resolutions. PMID:27610090

  8. Locality and Word Order in Active Dependency Formation in Bangla.

    PubMed

    Chacón, Dustin A; Imtiaz, Mashrur; Dasgupta, Shirsho; Murshed, Sikder M; Dan, Mina; Phillips, Colin

    2016-01-01

    Research on filler-gap dependencies has revealed that there are constraints on possible gap sites, and that real-time sentence processing is sensitive to these constraints. This work has shown that comprehenders have preferences for potential gap sites, and immediately detect when these preferences are not met. However, neither the mechanisms that select preferred gap sites nor the mechanisms used to detect whether these preferences are met are well-understood. In this paper, we report on three experiments in Bangla, a language in which gaps may occur in either a pre-verbal embedded clause or a post-verbal embedded clause. This word order variation allows us to manipulate whether the first gap linearly available is contained in the same clause as the filler, which allows us to dissociate structural locality from linear locality. In Experiment 1, an untimed ambiguity resolution task, we found a global bias to resolve a filler-gap dependency with the first gap linearly available, regardless of structural hierarchy. In Experiments 2 and 3, which use the filled-gap paradigm, we found sensitivity to disruption only when the blocked gap site is both structurally and linearly local, i.e., the filler and the gap site are contained in the same clause. This suggests that comprehenders may not show sensitivity to the disruption of all preferred gap resolutions.

  9. Parallel or serial activation of word forms in speech production? Neurolinguistic evidence from an aphasic patient.

    PubMed

    Blanken, Gerhard; Dittmann, Jürgen; Wallesch, Claus-W

    2002-05-31

    We report the oral picture naming performance of the German aphasic MW who presented with frequent meaning related word substitutions (e.g. tiger ==> lion) and word finding blockings (omissions) while his phonological capacities at the single word level were nearly preserved. Targets were controlled for their 'semantic competitiveness', that is, whether there exist closely meaning related lexical competitors or not. Semantic errors were far more numerous with the highly competitive targets than with the low competitive ones. However, omissions were more frequent with the low competitive items so that the sum of the semantic errors and of the omissions was comparable in both conditions. This inverse and compensatory relationship suggests that both error types are not mutually independent. The found pattern is at odds with serial psycholinguistic theories which locate word selection (and misselection) and word form access (and blockings) at different and serially connected stages of word production but supports theories which allow for a parallel architecture in lexical activation and selection involving the word form level.

  10. Parallel language activation and cognitive control during spoken word recognition in bilinguals

    PubMed Central

    Blumenfeld, Henrike K.; Marian, Viorica

    2013-01-01

    Accounts of bilingual cognitive advantages suggest an associative link between cross-linguistic competition and inhibitory control. We investigate this link by examining English-Spanish bilinguals’ parallel language activation during auditory word recognition and nonlinguistic Stroop performance. Thirty-one English-Spanish bilinguals and 30 English monolinguals participated in an eye-tracking study. Participants heard words in English (e.g., comb) and identified corresponding pictures from a display that included pictures of a Spanish competitor (e.g., conejo, English rabbit). Bilinguals with higher Spanish proficiency showed more parallel language activation and smaller Stroop effects than bilinguals with lower Spanish proficiency. Across all bilinguals, stronger parallel language activation between 300–500ms after word onset was associated with smaller Stroop effects; between 633–767ms, reduced parallel language activation was associated with smaller Stroop effects. Results suggest that bilinguals who perform well on the Stroop task show increased cross-linguistic competitor activation during early stages of word recognition and decreased competitor activation during later stages of word recognition. Findings support the hypothesis that cross-linguistic competition impacts domain-general inhibition. PMID:24244842

  11. The Effects of Word Walls and Word Wall Activities on the Reading Fluency of First Grade Students

    ERIC Educational Resources Information Center

    Jasmine, Joanne; Schiesl, Pamela

    2009-01-01

    Reading fluency is the ability to read orally with speed and efficiency, including word recognition, decoding, and comprehension (Chard & Pikulski, 2005). Able readers achieve fluency as they recognize words with speed and build upon them to aid in comprehension (Pumfrey & Elliott, 1990). One way to help students achieve fluency is through the use…

  12. Embodiment and second-language: automatic activation of motor responses during processing spatially associated L2 words and emotion L2 words in a vertical Stroop paradigm.

    PubMed

    Dudschig, Carolin; de la Vega, Irmgard; Kaup, Barbara

    2014-05-01

    Converging evidence suggests that understanding our first-language (L1) results in reactivation of experiential sensorimotor traces in the brain. Surprisingly, little is known regarding the involvement of these processes during second-language (L2) processing. Participants saw L1 or L2 words referring to entities with a typical location (e.g., star, mole) (Experiment 1 & 2) or to an emotion (e.g., happy, sad) (Experiment 3). Participants responded to the words' ink color with an upward or downward arm movement. Despite word meaning being fully task-irrelevant, L2 automatically activated motor responses similar to L1 even when L2 was acquired rather late in life (age >11). Specifically, words such as star facilitated upward, and words such as root facilitated downward responses. Additionally, words referring to positive emotions facilitated upward, and words referring to negative emotions facilitated downward responses. In summary our study suggests that reactivation of experiential traces is not limited to L1 processing.

  13. Pre-Activation Negativity (PrAN) in Brain Potentials to Unfolding Words

    PubMed Central

    Söderström, Pelle; Horne, Merle; Frid, Johan; Roll, Mikael

    2016-01-01

    We describe an event-related potential (ERP) effect termed the “pre-activation negativity” (PrAN), which is proposed to index the degree of pre-activation of upcoming word-internal morphemes in speech processing. Using lexical competition measures based on word-initial speech fragments (WIFs), as well as statistical analyses of ERP data from three experiments, it is shown that the PrAN is sensitive to lexical competition and that it reflects the degree of predictive certainty: the negativity is larger when there are fewer upcoming lexical competitors. PMID:27777558

  14. Language co-activation and lexical selection in bimodal bilinguals: Evidence from picture–word interference*

    PubMed Central

    GIEZEN, MARCEL R.; EMMOREY, KAREN

    2015-01-01

    We used picture–word interference (PWI) to discover a) whether cross-language activation at the lexical level can yield phonological priming effects when languages do not share phonological representations, and b) whether semantic interference effects occur without articulatory competition. Bimodal bilinguals fluent in American Sign Language (ASL) and English named pictures in ASL while listening to distractor words that were 1) translation equivalents, 2) phonologically related to the target sign through translation, 3) semantically related, or 4) unrelated. Monolingual speakers named pictures in English. Production of ASL signs was facilitated by words that were phonologically related through translation and by translation equivalents, indicating that cross-language activation spreads from lexical to phonological levels for production. Semantic interference effects were not observed for bimodal bilinguals, providing some support for a post-lexical locus of semantic interference, but which we suggest may instead reflect time course differences in spoken and signed production in the PWI task. PMID:26989347

  15. Skilled adult readers activate the meanings of high-frequency words using phonology: Evidence from eye tracking.

    PubMed

    Jared, Debra; O'Donnell, Katrina

    2017-02-01

    We examined whether highly skilled adult readers activate the meanings of high-frequency words using phonology when reading sentences for meaning. A homophone-error paradigm was used. Sentences were written to fit 1 member of a homophone pair, and then 2 other versions were created in which the homophone was replaced by its mate or a spelling-control word. The error words were all high-frequency words, and the correct homophones were either higher-frequency words or low-frequency words-that is, the homophone errors were either the subordinate or dominant member of the pair. Participants read sentences as their eye movements were tracked. When the high-frequency homophone error words were the subordinate member of the homophone pair, participants had shorter immediate eye-fixation latencies on these words than on matched spelling-control words. In contrast, when the high-frequency homophone error words were the dominant member of the homophone pair, a difference between these words and spelling controls was delayed. These findings provide clear evidence that the meanings of high-frequency words are activated by phonological representations when skilled readers read sentences for meaning. Explanations of the differing patterns of results depending on homophone dominance are discussed.

  16. Exploring Key Sustainable Development Themes through Learning Activities

    ERIC Educational Resources Information Center

    Cruickshank, Heather; Fenner, Richard

    2012-01-01

    Purpose: The purpose of the paper is to examine how a number of key themes are introduced in the Master's programme in Engineering for Sustainable Development, at Cambridge University, through student-centred activities. These themes include dealing with complexity, uncertainty, change, other disciplines, people, environmental limits, whole life…

  17. The Activation and Monitoring of Memories Produced by Words and Pseudohomophones

    ERIC Educational Resources Information Center

    Cortese, Michael J.; Khanna, Maya M.; White, Katherine K.; Veljkovic, Ilija; Drumm, Geoffery

    2008-01-01

    Using the DRM paradigm, our experiments examined the activation and monitoring of memories in semantic and phonological networks. Participants viewed lists of words and/or pseudohomophones (e.g., "dreem"). In Experiment 1, participants verbally recalled lists of semantic associates or attempted to write them as they appeared during study. False…

  18. The evocative power of words: activation of concepts by verbal and nonverbal means.

    PubMed

    Lupyan, Gary; Thompson-Schill, Sharon L

    2012-02-01

    A major part of learning a language is learning to map spoken words onto objects in the environment. An open question is what are the consequences of this learning for cognition and perception? Here, we present a series of experiments that examine effects of verbal labels on the activation of conceptual information as measured through picture verification tasks. We find that verbal cues, such as the word "cat," lead to faster and more accurate verification of congruent objects and rejection of incongruent objects than do either nonverbal cues, such as the sound of a cat meowing, or words that do not directly refer to the object, such as the word "meowing." This label advantage does not arise from verbal labels being more familiar or easier to process than other cues, and it does extends to newly learned labels and sounds. Despite having equivalent facility in learning associations between novel objects and labels or sounds, conceptual information is activated more effectively through verbal means than through nonverbal means. Thus, rather than simply accessing nonverbal concepts, language activates aspects of a conceptual representation in a particularly effective way. We offer preliminary support that representations activated via verbal means are more categorical and show greater consistency between subjects. These results inform the understanding of how human cognition is shaped by language and hint at effects that different patterns of naming can have on conceptual structure.

  19. Tracing Attention and the Activation Flow of Spoken Word Planning Using Eye Movements

    ERIC Educational Resources Information Center

    Roelofs, Ardi

    2008-01-01

    The flow of activation from concepts to phonological forms within the word production system was examined in 3 experiments. In Experiment 1, participants named pictures while ignoring superimposed distractor pictures that were semantically related, phonologically related, or unrelated. Eye movements and naming latencies were recorded. The…

  20. The Evocative Power of Words: Activation of Concepts by Verbal and Nonverbal Means

    PubMed Central

    Lupyan, Gary; Thompson-Schill, Sharon L.

    2014-01-01

    A major part of learning a language is learning to map spoken words onto objects in the environment. An open question is what are the consequences of this learning for cognition and perception? Here, we present a series of experiments that examine effects of verbal labels on the activation of conceptual information as measured through picture verification tasks. We find that verbal cues, such as the word “cat,” lead to faster and more accurate verification of congruent objects and rejection of incongruent objects than do either nonverbal cues, such as the sound of a cat meowing, or words that do not directly refer to the object, such as the word “meowing.” This label advantage does not arise from verbal labels being more familiar or easier to process than other cues, and it does extends to newly learned labels and sounds. Despite having equivalent facility in learning associations between novel objects and labels or sounds, conceptual information is activated more effectively through verbal means than through non-verbal means. Thus, rather than simply accessing nonverbal concepts, language activates aspects of a conceptual representation in a particularly effective way. We offer preliminary support that representations activated via verbal means are more categorical and show greater consistency between subjects. These results inform the understanding of how human cognition is shaped by language and hint at effects that different patterns of naming can have on conceptual structure. PMID:21928923

  1. Phonological Activation during Visual Word Recognition in Deaf and Hearing Children

    ERIC Educational Resources Information Center

    Ormel, Ellen; Hermans, Daan; Knoors, Harry; Hendriks, Angelique; Verhoeven, Ludo

    2010-01-01

    Purpose: Phonological activation during visual word recognition was studied in deaf and hearing children under two circumstances: (a) when the use of phonology was not required for task performance and might even hinder it and (b) when the use of phonology was critical for task performance. Method: Deaf children mastering written Dutch and Sign…

  2. Higher-Order Activity beyond the Word Level: Cortical Dynamics of Simple Transitive Sentence Comprehension

    ERIC Educational Resources Information Center

    Martin-Loeches, M.; Casado, P.; Hinojosa, J.A.; Carretie, L.; Munoz, F.; Pozo, M.A.

    2005-01-01

    Slow electrophysiological effects, which fluctuate throughout the course of a sentence, independent of transient responses to individual words, have been reported. However, this type of activity has scarcely been studied, and with only limited use of electrophysiological information, so that the brain areas in which these variations originate have…

  3. Automatic Evaluation Stimuli - The Most Frequently Used Words to Describe Physical Activity and the Pleasantness of Physical Activity.

    PubMed

    Rebar, Amanda L; Schoeppe, Stephanie; Alley, Stephanie J; Short, Camille E; Dimmock, James A; Jackson, Ben; Conroy, David E; Rhodes, Ryan E; Vandelanotte, Corneel

    2016-01-01

    Physical activity is partially regulated by non-conscious processes including automatic evaluations - the spontaneous affective reactions we have to physical activity that lead us to approach or avoid physical activity opportunities. A sound understanding of which words best represent the concepts of physical activity and pleasantness (as associated with physical activity) is needed to improve the measurement of automatic evaluations and related constructs (e.g., automatic self-schemas, attentional biases). The first aim of this study was to establish population-level evidence of the most common word stimuli for physical activity and pleasantness. Given that response latency measures have been applied to assess automatic evaluations of physical activity and exercise, the second aim was to determine whether people use the same behavior and pleasant descriptors for physical activity and exercise. Australian adults (N = 1,318; 54.3% women; 48.9% aged 55 years or older) were randomly assigned to one of two groups, through a computer-generated 1:1 ratio allocation, to be asked to list either five behaviors and pleasant descriptors of physical activity (n = 686) or of exercise (n = 632). The words were independently coded twice as to whether they were novel words or the same as another (i.e., same stem or same meaning). Intercoder reliability varied between moderate and strong (agreement = 50.1 to 97.8%; κ = 0.48 to 0.82). A list of the 20 most common behavior and pleasantness words were established based on how many people reported them, weighted by the ranking (1-5) people gave them. The words people described as physical activity were mostly the same as those people used to describe exercise. The most common behavior words were 'walking,' 'running,' 'swimming,' 'bike riding,' and 'gardening'; and the most common pleasant descriptor words were 'relaxing,' 'happiness,' 'enjoyment,' 'exhilarating,' 'exhausting,' and 'good.' These sets of stimuli can be utilized as

  4. Automatic Evaluation Stimuli – The Most Frequently Used Words to Describe Physical Activity and the Pleasantness of Physical Activity

    PubMed Central

    Rebar, Amanda L.; Schoeppe, Stephanie; Alley, Stephanie J.; Short, Camille E.; Dimmock, James A.; Jackson, Ben; Conroy, David E.; Rhodes, Ryan E.; Vandelanotte, Corneel

    2016-01-01

    Physical activity is partially regulated by non-conscious processes including automatic evaluations – the spontaneous affective reactions we have to physical activity that lead us to approach or avoid physical activity opportunities. A sound understanding of which words best represent the concepts of physical activity and pleasantness (as associated with physical activity) is needed to improve the measurement of automatic evaluations and related constructs (e.g., automatic self-schemas, attentional biases). The first aim of this study was to establish population-level evidence of the most common word stimuli for physical activity and pleasantness. Given that response latency measures have been applied to assess automatic evaluations of physical activity and exercise, the second aim was to determine whether people use the same behavior and pleasant descriptors for physical activity and exercise. Australian adults (N = 1,318; 54.3% women; 48.9% aged 55 years or older) were randomly assigned to one of two groups, through a computer-generated 1:1 ratio allocation, to be asked to list either five behaviors and pleasant descriptors of physical activity (n = 686) or of exercise (n = 632). The words were independently coded twice as to whether they were novel words or the same as another (i.e., same stem or same meaning). Intercoder reliability varied between moderate and strong (agreement = 50.1 to 97.8%; κ = 0.48 to 0.82). A list of the 20 most common behavior and pleasantness words were established based on how many people reported them, weighted by the ranking (1–5) people gave them. The words people described as physical activity were mostly the same as those people used to describe exercise. The most common behavior words were ‘walking,’ ‘running,’ ‘swimming,’ ‘bike riding,’ and ‘gardening’; and the most common pleasant descriptor words were ‘relaxing,’ ‘happiness,’ ‘enjoyment,’ ‘exhilarating,’ ‘exhausting,’ and

  5. Brain activations associated with sign production using word and picture inputs in deaf signers.

    PubMed

    Hu, Zhiguo; Wang, Wenjing; Liu, Hongyan; Peng, Danling; Yang, Yanhui; Li, Kuncheng; Zhang, John X; Ding, Guosheng

    2011-02-01

    Effective literacy education in deaf students calls for psycholinguistic research revealing the cognitive and neural mechanisms underlying their written language processing. When learning a written language, deaf students are often instructed to sign out printed text. The present fMRI study was intended to reveal the neural substrates associated with word signing by comparing it with picture signing. Native deaf signers were asked to overtly sign in Chinese Sign Language (CSL) common objects indicated with written words or presented as pictures. Except in left inferior frontal gyrus and inferior parietal lobule where word signing elicited greater activation than picture signing, the two tasks engaged a highly overlapping set of brain regions previously implicated in sign production. The results suggest that word signing in the deaf signers relies on meaning activation from printed visual forms, followed by similar production processes from meaning to signs as in picture signing. The present study also documents the basic brain activation pattern for sign production in CSL and supports the notion of a universal core neural network for sign production across different sign languages.

  6. Auditory selective attention to speech modulates activity in the visual word form area.

    PubMed

    Yoncheva, Yuliya N; Zevin, Jason D; Maurer, Urs; McCandliss, Bruce D

    2010-03-01

    Selective attention to speech versus nonspeech signals in complex auditory input could produce top-down modulation of cortical regions previously linked to perception of spoken, and even visual, words. To isolate such top-down attentional effects, we contrasted 2 equally challenging active listening tasks, performed on the same complex auditory stimuli (words overlaid with a series of 3 tones). Instructions required selectively attending to either the speech signals (in service of rhyme judgment) or the melodic signals (tone-triplet matching). Selective attention to speech, relative to attention to melody, was associated with blood oxygenation level-dependent (BOLD) increases during functional magnetic resonance imaging (fMRI) in left inferior frontal gyrus, temporal regions, and the visual word form area (VWFA). Further investigation of the activity in visual regions revealed overall deactivation relative to baseline rest for both attention conditions. Topographic analysis demonstrated that while attending to melody drove deactivation equivalently across all fusiform regions of interest examined, attending to speech produced a regionally specific modulation: deactivation of all fusiform regions, except the VWFA. Results indicate that selective attention to speech can topographically tune extrastriate cortex, leading to increased activity in VWFA relative to surrounding regions, in line with the well-established connectivity between areas related to spoken and visual word perception in skilled readers.

  7. Active magnetic radiation shielding system analysis and key technologies.

    PubMed

    Washburn, S A; Blattnig, S R; Singleterry, R C; Westover, S C

    2015-01-01

    Many active magnetic shielding designs have been proposed in order to reduce the radiation exposure received by astronauts on long duration, deep space missions. While these designs are promising, they pose significant engineering challenges. This work presents a survey of the major systems required for such unconfined magnetic field design, allowing the identification of key technologies for future development. Basic mass calculations are developed for each system and are used to determine the resulting galactic cosmic radiation exposure for a generic solenoid design, using a range of magnetic field strength and thickness values, allowing some of the basic characteristics of such a design to be observed. This study focuses on a solenoid shaped, active magnetic shield design; however, many of the principles discussed are applicable regardless of the exact design configuration, particularly the key technologies cited.

  8. Task-dependent Modulations of Prefrontal and Hippocampal Activity during Intrinsic Word Production

    PubMed Central

    Whitney, Carin; Weis, Susanne; Krings, Timo; Huber, Walter; Grossman, Murray; Kircher, Tilo

    2009-01-01

    Functional imaging studies of single word production have consistently reported activation of the lateral prefrontal and cingulate cortex. Its contribution has been shown to be sensitive to task demands, which can be manipulated by the degree of response specification. Compared with classical verbal fluency, free word association relies less on response restrictions but to a greater extent on associative binding processes, usually subserved by the hippocampus. To elucidate the relevance of the frontal and medial-temporal areas during verbal retrieval tasks, we applied varying degrees of response specification. During fMRI data acquisition, 18 subjects performed a free verbal association (FVA), a semantic verbal fluency (SVF) task, and a phonological verbal fluency (PVF) task. Externally guided word production served as a baseline condition to control for basic articulatory and reading processes. As expected, increased brain activity was observed in the left lateral and bilateral medial frontal cortices for SVF and PVF. The anterior cingulate gyrus was the only structure common to both fluency tasks in direct comparison to the less restricted FVA task. The hippocampus was engaged during associative and semantic retrieval. Interestingly, hippocampal activity was selectively evident during FVA in direct comparison to SVF when it was controlled for stimulus–response relations. The current data confirm the role of the left prefrontal–cingulate network in constrained word production. Hippocampal activity during spontaneous word production is a novel finding and seems to be dependent on the retrieval process (free vs. constrained) rather than the variety of stimulus–response relationships that is involved. PMID:18578599

  9. A dual-route perspective on brain activation in response to visual words: evidence for a length by lexicality interaction in the visual word form area (VWFA).

    PubMed

    Schurz, Matthias; Sturm, Denise; Richlan, Fabio; Kronbichler, Martin; Ladurner, Gunther; Wimmer, Heinz

    2010-02-01

    Based on our previous work, we expected the Visual Word Form Area (VWFA) in the left ventral visual pathway to be engaged by both whole-word recognition and by serial sublexical coding of letter strings. To examine this double function, a phonological lexical decision task (i.e., "Does xxx sound like an existing word?") presented short and long letter strings of words, pseudohomophones, and pseudowords (e.g., Taxi, Taksi and Tazi). Main findings were that the length effect for words was limited to occipital regions and absent in the VWFA. In contrast, a marked length effect for pseudowords was found throughout the ventral visual pathway including the VWFA, as well as in regions presumably engaged by visual attention and silent-articulatory processes. The length by lexicality interaction on brain activation corresponds to well-established behavioral findings of a length by lexicality interaction on naming latencies and speaks for the engagement of the VWFA by both lexical and sublexical processes.

  10. Reading as active sensing: a computational model of gaze planning in word recognition.

    PubMed

    Ferro, Marcello; Ognibene, Dimitri; Pezzulo, Giovanni; Pirrelli, Vito

    2010-01-01

    WE OFFER A COMPUTATIONAL MODEL OF GAZE PLANNING DURING READING THAT CONSISTS OF TWO MAIN COMPONENTS: a lexical representation network, acquiring lexical representations from input texts (a subset of the Italian CHILDES database), and a gaze planner, designed to recognize written words by mapping strings of characters onto lexical representations. The model implements an active sensing strategy that selects which characters of the input string are to be fixated, depending on the predictions dynamically made by the lexical representation network. We analyze the developmental trajectory of the system in performing the word recognition task as a function of both increasing lexical competence, and correspondingly increasing lexical prediction ability. We conclude by discussing how our approach can be scaled up in the context of an active sensing strategy applied to a robotic setting.

  11. Reading as Active Sensing: A Computational Model of Gaze Planning in Word Recognition

    PubMed Central

    Ferro, Marcello; Ognibene, Dimitri; Pezzulo, Giovanni; Pirrelli, Vito

    2010-01-01

    We offer a computational model of gaze planning during reading that consists of two main components: a lexical representation network, acquiring lexical representations from input texts (a subset of the Italian CHILDES database), and a gaze planner, designed to recognize written words by mapping strings of characters onto lexical representations. The model implements an active sensing strategy that selects which characters of the input string are to be fixated, depending on the predictions dynamically made by the lexical representation network. We analyze the developmental trajectory of the system in performing the word recognition task as a function of both increasing lexical competence, and correspondingly increasing lexical prediction ability. We conclude by discussing how our approach can be scaled up in the context of an active sensing strategy applied to a robotic setting. PMID:20577589

  12. Word wins over face: emotional Stroop effect activates the frontal cortical network.

    PubMed

    Ovaysikia, Shima; Tahir, Khalid A; Chan, Jason L; DeSouza, Joseph F X

    2011-01-01

    The prefrontal cortex (PFC) has been implicated in higher order cognitive control of behavior. Sometimes such control is executed through suppression of an unwanted response in order to avoid conflict. Conflict occurs when two simultaneously competing processes lead to different behavioral outcomes, as seen in tasks such as the anti-saccade, go/no-go, and the Stroop task. We set out to examine whether different types of stimuli in a modified emotional Stroop task would cause similar interference effects as the original Stroop-color/word, and whether the required suppression mechanism(s) would recruit similar regions of the medial PFC (mPFC). By using emotional words and emotional faces in this Stroop experiment, we examined the two well-learned automatic behaviors of word reading and recognition of face expressions. In our emotional Stroop paradigm, words were processed faster than face expressions with incongruent trials yielding longer reaction times and larger number of errors compared to the congruent trials. This novel Stroop effect activated the anterior and inferior regions of the mPFC, namely the anterior cingulate cortex, inferior frontal gyrus as well as the superior frontal gyrus. Our results suggest that prepotent behaviors such as reading and recognition of face expressions are stimulus-dependent and perhaps hierarchical, hence recruiting distinct regions of the mPFC. Moreover, the faster processing of word reading compared to reporting face expressions is indicative of the formation of stronger stimulus-response associations of an over-learned behavior compared to an instinctive one, which could alternatively be explained through the distinction between awareness and selective attention.

  13. Product Descriptions; Word Processors and Writing Activities for the Elementary Grades. A MicroSIFT Quarterly Report.

    ERIC Educational Resources Information Center

    Batey, Anne; Ricketts, Dick

    Intended to help educators choose the most appropriate word processing products for elementary school writing instruction, this report provides extensive information on 12 word processor and 13 writing activity software products. A list of components, general descriptions, comments and evaluations are included for each product. The products…

  14. Language experience differentiates prefrontal and subcortical activation of the cognitive control network in novel word learning

    PubMed Central

    King, Kelly E.; Hernandez, Arturo E.

    2012-01-01

    The purpose of this study was to examine the cognitive control mechanisms in adult English speaking monolinguals compared to early sequential Spanish-English bilinguals during the initial stages of novel word learning. Functional magnetic resonance imaging during a lexico-semantic task after only two hours of exposure to novel German vocabulary flashcards showed that monolinguals activated a broader set of cortical control regions associated with higher-level cognitive processes, including the supplementary motor area (SMA), anterior cingulate (ACC), and dorsolateral prefrontal cortex (DLPFC), as well as the caudate, implicated in cognitive control of language. However, bilinguals recruited a more localized subcortical network that included the putamen, associated more with motor control of language. These results suggest that experience managing multiple languages may differentiate the learning strategy and subsequent neural mechanisms of cognitive control used by bilinguals compared to monolinguals in the early stages of novel word learning. PMID:23194816

  15. Key Words in Instruction. More than Activities--Hopefully a Language of Ideas

    ERIC Educational Resources Information Center

    Callison, Daniel

    2005-01-01

    This column lists and defines several sets of selected terms that may better help any educator communicate with the digital-savvy student clientele. Terms were gathered from the sources listed in "Further Reading" and confirmed among three online professors at Indiana University/Purdue University at Indianapolis. The sample terms are clustered by…

  16. Word prediction

    SciTech Connect

    Rumelhart, D.E.; Skokowski, P.G.; Martin, B.O.

    1995-05-01

    In this project we have developed a language model based on Artificial Neural Networks (ANNs) for use in conjunction with automatic textual search or speech recognition systems. The model can be trained on large corpora of text to produce probability estimates that would improve the ability of systems to identify words in a sentence given partial contextual information. The model uses a gradient-descent learning procedure to develop a metric of similarity among terms in a corpus, based on context. Using lexical categories based on this metric, a network can then be trained to do serial word probability estimation. Such a metric can also be used to improve the performance of topic-based search by allowing retrieval of information that is related to desired topics even if no obvious set of key words unites all the retrieved items.

  17. Active listening: The key of successful communication in hospital managers

    PubMed Central

    Jahromi, Vahid Kohpeima; Tabatabaee, Seyed Saeed; Abdar, Zahra Esmaeili; Rajabi, Mahboobeh

    2016-01-01

    Introduction One of the important causes of medical errors and unintentional harm to patients is ineffective communication. The important part of this skill, in case it has been forgotten, is listening. The objective of this study was to determine whether managers in hospitals listen actively. Methods This study was conducted between May and June 2014 among three levels of managers at teaching hospitals in Kerman, Iran. Active Listening skill among hospital managers was measured by self-made Active Listening Skill Scale (ALSS), which consists of the key elements of active listening and has five subscales, i.e., Avoiding Interruption, Maintaining Interest, Postponing Evaluation, Organizing Information, and Showing Interest. The data were analyzed by IBM-SPSS software, version 20, and the Pearson product-moment correlation coefficient, the chi-squared test, and multiple linear regressions. Results The mean score of active listening in hospital managers was 2.32 out of 3.The highest score (2.27) was obtained by the first-level managers, and the top managers got the lowest score (2.16). Hospital mangers were best in showing interest and worst in avoiding interruptions. The area of employment was a significant predictor of avoiding interruption and the managers’ gender was a strong predictor of skill in maintaining interest (p < 0.05). The type of management and education can predict postponing evaluation, and the length of employment can predict showing interest (p < 0.05). Conclusion There is a necessity for the development of strategies to create more awareness among the hospital managers concerning their active listening skills. PMID:27123221

  18. Hypofrontal activity during word retrieval in older adults: a near-infrared spectroscopy study.

    PubMed

    Obayashi, Shigeru; Hara, Yukihiro

    2013-02-01

    The supplementary motor area (SMA) has been regarded as a third speech area. The SMA is anatomically classified into two regions, pre-SMA and SMA proper, but the functional specialization of speech production between the two regions remains unknown. Although word retrieval difficulties were often observed in older adults, there was no report as to whether the SMA would be involved in the retrieval difficulties. We focused on the SMA as a function of word production and then used near-infrared spectroscopy (NIRS) with the verbal fluency task (VFT) to explore the possible mechanism underlying the retrieval difficulties related to aging. Based on the anatomical differences within the SMA, we relied on region-of-interest (ROI) analysis to compare the brain activation patterns in the SMA during VFT between 11 healthy elder and 11 younger subjects in the situation where both groups show comparable task performance. Notably, the anterior VFT-related SMA response was more robust in the younger than in the elder group. Furthermore, anterior SMA responses in the elder group may only have a positive correlation with the VFT performance. The findings imply that anterior SMA hypoactivity in elders may cause word retrieval difficulties, while bilateral prefrontal cortices, having close connection with the pre-SMA, may contribute to the compensatory process that enables equivalent performance of the elder group with the younger one.

  19. Selective Activation Around the Left Occipito-Temporal Sulcus for Words Relative to Pictures: Individual Variability or False Positives?

    PubMed Central

    Wright, Nicholas D; Mechelli, Andrea; Noppeney, Uta; Veltman, Dick J; Rombouts, Serge ARB; Glensman, Janice; Haynes, John-Dylan; Price, Cathy J

    2008-01-01

    We used high-resolution fMRI to investigate claims that learning to read results in greater left occipito-temporal (OT) activation for written words relative to pictures of objects. In the first experiment, 9/16 subjects performing a one-back task showed activation in ≥1 left OT voxel for words relative to pictures (P < 0.05 uncorrected). In a second experiment, another 9/15 subjects performing a semantic decision task activated ≥1 left OT voxel for words relative to pictures. However, at this low statistical threshold false positives need to be excluded. The semantic decision paradigm was therefore repeated, within subject, in two different scanners (1.5 and 3 T). Both scanners consistently localised left OT activation for words relative to fixation and pictures relative to words, but there were no consistent effects for words relative to pictures. Finally, in a third experiment, we minimised the voxel size (1.5 × 1.5 × 1.5 mm3) and demonstrated a striking concordance between the voxels activated for words and pictures, irrespective of task (naming vs. one-back) or script (English vs. Hebrew). In summary, although we detected differential activation for words relative to pictures, these effects: (i) do not withstand statistical rigour; (ii) do not replicate within or between subjects; and (iii) are observed in voxels that also respond to pictures of objects. Our findings have implications for the role of left OT activation during reading. More generally, they show that studies using low statistical thresholds in single subject analyses should correct the statistical threshold for the number of comparisons made or replicate effects within subject. Hum Brain Mapp 2008. © 2007 Wiley-Liss, Inc. PMID:17712786

  20. Increased anterior cingulate cortex and hippocampus activation in Complex PTSD during encoding of negative words

    PubMed Central

    Dorrepaal, Ethy; Draijer, Nel; de Ruiter, Michiel B.; Elzinga, Bernet M.; Sjoerds, Zsuzsika; van Balkom, Anton J.; Smit, Johannes H.; Veltman, Dick J.

    2013-01-01

    Post-traumatic stress disorder (PTSD) is associated with impaired memory performance coupled with functional changes in brain areas involved in declarative memory and emotion regulation. It is not yet clear how symptom severity and comorbidity affect neurocognitive functioning in PTSD. We performed a functional magnetic resonance imaging (fMRI) study with an emotional declarative memory task in 28 Complex PTSD patients with comorbid depressive and personality disorders, and 21 healthy non-trauma-exposed controls. In Complex PTSD patients—compared to controls—encoding of later remembered negative words vs baseline was associated with increased blood oxygenation level dependent (BOLD) response in the left ventral anterior cingulate cortex (ACC) and dorsal ACC extending to the dorsomedial prefrontal cortex (dmPFC) together with a trend for increased left hippocampus activation. Patients tended to commit more False Alarms to negative words compared to controls, which was associated with enhanced left ventrolateral prefrontal and orbitofrontal cortex (vlPFC/OFC) responses. Severity of child abuse was positively correlated with left ventral ACC activity and severity of depression with (para) hippocampal and ventral ACC activity. Presented results demonstrate functional abnormalities in Complex PTSD in the frontolimbic brain circuit also implicated in fear conditioning models, but generally in the opposite direction, which may be explained by severity of the trauma and severity of comorbid depression in Complex PTSD. PMID:22156722

  1. Feature activation during word recognition: action, visual, and associative-semantic priming effects

    PubMed Central

    Lam, Kevin J. Y.; Dijkstra, Ton; Rueschemeyer, Shirley-Ann

    2015-01-01

    Embodied theories of language postulate that language meaning is stored in modality-specific brain areas generally involved in perception and action in the real world. However, the temporal dynamics of the interaction between modality-specific information and lexical-semantic processing remain unclear. We investigated the relative timing at which two types of modality-specific information (action-based and visual-form information) contribute to lexical-semantic comprehension. To this end, we applied a behavioral priming paradigm in which prime and target words were related with respect to (1) action features, (2) visual features, or (3) semantically associative information. Using a Go/No-Go lexical decision task, priming effects were measured across four different inter-stimulus intervals (ISI = 100, 250, 400, and 1000 ms) to determine the relative time course of the different features. Notably, action priming effects were found in ISIs of 100, 250, and 1000 ms whereas a visual priming effect was seen only in the ISI of 1000 ms. Importantly, our data suggest that features follow different time courses of activation during word recognition. In this regard, feature activation is dynamic, measurable in specific time windows but not in others. Thus the current study (1) demonstrates how multiple ISIs can be used within an experiment to help chart the time course of feature activation and (2) provides new evidence for embodied theories of language. PMID:26074836

  2. Shape Representation of Word Was Automatically Activated in the Encoding Phase

    PubMed Central

    Zeng, Tianyu; Zheng, Liling; Mo, Lei

    2016-01-01

    Theories of embodied language comprehension have proposed that language processing includes perception simulation and activation of sensorimotor representation. Previous studies have used a numerical priming paradigm to test the priming effect of semantic size, and the negative result showed that the sensorimotor representation has not been activated during the encoding phase. Considering that the size property is unstable, here we changed the target property to examine the priming effect of semantic shape using the same paradigm. The participants would see three different object names successively, and then they were asked to decide whether the shape of the second referent was more similar to the first one or the third one. In the eye-movement experiment, the encoding time showed a distance-priming effect, as the similarity of shapes between the first referent and the second referent increased, the encoding time of the second word gradually decreased. In the event-related potentials experiment, when the difference of shapes between the first referent and the second referent increased, the N400 amplitude became larger. These findiings suggested that the shape information of a word was activated during the encoding phase, providing supportive evidence for the embodied theory of language comprehension. PMID:27788236

  3. Electronic Word of Mouth on Twitter About Physical Activity in the United States: Exploratory Infodemiology Study

    PubMed Central

    Campo, Shelly; Janz, Kathleen F; Eckler, Petya; Yang, Jingzhen; Snetselaar, Linda G; Signorini, Alessio

    2013-01-01

    Background Twitter is a widely used social medium. However, its application in promoting health behaviors is understudied. Objective In order to provide insights into designing health marketing interventions to promote physical activity on Twitter, this exploratory infodemiology study applied both social cognitive theory and the path model of online word of mouth to examine the distribution of different electronic word of mouth (eWOM) characteristics among personal tweets about physical activity in the United States. Methods This study used 113 keywords to retrieve 1 million public tweets about physical activity in the United States posted between January 1 and March 31, 2011. A total of 30,000 tweets were randomly selected and sorted based on numbers generated by a random number generator. Two coders scanned the first 16,100 tweets and yielded 4672 (29.02%) tweets that they both agreed to be about physical activity and were from personal accounts. Finally, 1500 tweets were randomly selected from the 4672 tweets (32.11%) for further coding. After intercoder reliability scores reached satisfactory levels in the pilot coding (100 tweets separate from the final 1500 tweets), 2 coders coded 750 tweets each. Descriptive analyses, Mann-Whitney U tests, and Fisher exact tests were performed. Results Tweets about physical activity were dominated by neutral sentiments (1270/1500, 84.67%). Providing opinions or information regarding physical activity (1464/1500, 97.60%) and chatting about physical activity (1354/1500, 90.27%) were found to be popular on Twitter. Approximately 60% (905/1500, 60.33%) of the tweets demonstrated users’ past or current participation in physical activity or intentions to participate in physical activity. However, social support about physical activity was provided in less than 10% of the tweets (135/1500, 9.00%). Users with fewer people following their tweets (followers) (P=.02) and with fewer accounts that they followed (followings) (P=.04

  4. Team activity recognition in Association Football using a Bag-of-Words-based method.

    PubMed

    Montoliu, Raúl; Martín-Félez, Raúl; Torres-Sospedra, Joaquín; Martínez-Usó, Adolfo

    2015-06-01

    In this paper, a new methodology is used to perform team activity recognition and analysis in Association Football. It is based on pattern recognition and machine learning techniques. In particular, a strategy based on the Bag-of-Words (BoW) technique is used to characterize short Football video clips that are used to explain the team's performance and to train advanced classifiers in automatic recognition of team activities. In addition to the neural network-based classifier, three more classifier families are tested: the k-Nearest Neighbor, the Support Vector Machine and the Random Forest. The results obtained show that the proposed methodology is able to explain the most common movements of a team and to perform the team activity recognition task with high accuracy when classifying three Football actions: Ball Possession, Quick Attack and Set Piece. Random Forest is the classifier obtaining the best classification results.

  5. Learning to associate novel words with motor actions: language-induced motor activity following short training.

    PubMed

    Fargier, Raphaël; Paulignan, Yves; Boulenger, Véronique; Monaghan, Padraic; Reboul, Anne; Nazir, Tatjana A

    2012-07-01

    Action words referring to face, arm or leg actions activate areas along the motor strip that also control the planning and execution of the actions specified by the words. This electroencephalogram (EEG) study aimed to test the learning profile of this language-induced motor activity. Participants were trained to associate novel verbal stimuli to videos of object-oriented hand and arm movements or animated visual images on two consecutive days. Each training session was preceded and followed by a test-session with isolated videos and verbal stimuli. We measured motor-related brain activity (reflected by a desynchronization in the μ frequency bands; 8-12 Hz range) localized at centro-parietal and fronto-central electrodes. We compared activity from viewing the videos to activity resulting from processing the language stimuli only. At centro-parietal electrodes, stable action-related μ suppression was observed during viewing of videos in each test-session of the two days. For processing of verbal stimuli associated with motor actions, a similar pattern of activity was evident only in the second test-session of Day 1. Over the fronto-central regions, μ suppression was observed in the second test-session of Day 2 for the videos and in the second test-session of Day 1 for the verbal stimuli. Whereas the centro-parietal μ suppression can be attributed to motor events actually experienced during training, the fronto-central μ suppression seems to serve as a convergence zone that mediates underspecified motor information. Consequently, sensory-motor reactivations through which concepts are comprehended seem to differ in neural dynamics from those implicated in their acquisition.

  6. Key Words in Instruction. Bias

    ERIC Educational Resources Information Center

    Callison, Daniel

    2005-01-01

    Two challenging criteria for judging information involve bias and authority. In both cases, judgments may not be clearly possible. In both cases, there may be degrees or levels of acceptability. For students to gain experience and to demonstrate skills in making judgments, they need opportunities to consider a wide spectrum of resources under a…

  7. Effects of Lexicality and Word Frequency on Brain Activation in Dyslexic Readers

    ERIC Educational Resources Information Center

    Heim, Stefan; Wehnelt, Anke; Grande, Marion; Huber, Walter; Amunts, Katrin

    2013-01-01

    We investigated the neural basis of lexical access to written stimuli in adult dyslexics and normal readers via the Lexicality effect (pseudowords greater than words) and the Frequency effect (low greater than high frequent words). The participants read aloud German words (with low or high lexical frequency) or pseudowords while being scanned. In…

  8. When Deaf Signers Read English: Do Written Words Activate Their Sign Translations?

    ERIC Educational Resources Information Center

    Morford, Jill P.; Wilkinson, Erin; Villwock, Agnes.; Pinar, Pilar; Kroll, Judith F.

    2011-01-01

    Deaf bilinguals for whom American Sign Language (ASL) is the first language and English is the second language judged the semantic relatedness of word pairs in English. Critically, a subset of both the semantically related and unrelated word pairs were selected such that the translations of the two English words also had related forms in ASL. Word…

  9. Does viotin activate violin more than viocin? On the use of visual cues during visual-word recognition.

    PubMed

    Perea, Manuel; Panadero, Victoria

    2014-01-01

    The vast majority of neural and computational models of visual-word recognition assume that lexical access is achieved via the activation of abstract letter identities. Thus, a word's overall shape should play no role in this process. In the present lexical decision experiment, we compared word-like pseudowords like viotín (same shape as its base word: violín) vs. viocín (different shape) in mature (college-aged skilled readers), immature (normally reading children), and immature/impaired (young readers with developmental dyslexia) word-recognition systems. Results revealed similar response times (and error rates) to consistent-shape and inconsistent-shape pseudowords for both adult skilled readers and normally reading children - this is consistent with current models of visual-word recognition. In contrast, young readers with developmental dyslexia made significantly more errors to viotín-like pseudowords than to viocín-like pseudowords. Thus, unlike normally reading children, young readers with developmental dyslexia are sensitive to a word's visual cues, presumably because of poor letter representations.

  10. Premotor Cortex Activation Elicited during Word Comprehension Relies on Access of Specific Action Concepts.

    PubMed

    Lin, Nan; Wang, Xiaoying; Zhao, Ying; Liu, Yanping; Li, Xingshan; Bi, Yanchao

    2015-10-01

    The relationship between the lexical-semantic and sensory-motor systems is an important topic in cognitive neuroscience. An important finding indicating that these two systems interact is that reading action verbs activates the motor system of the human brain. Two constraints have been proposed to modulate this activation: the effector information associated with the action concepts and statistical regularities between sublexical features and grammatical classes. Using fMRI, we examined whether these two types of information can activate the motor system in the absence of specific motor-semantic content by manipulating the existence of a sublexical cue, called the hand radical, which strongly indicates the semantic feature "hand-related" and grammatical class "verb." Although hand radical characters referring to specific manual actions evoked stronger activation in the premotor cortex than the control characters, hand radical pseudocharacters did not evoke specific activation within the motor system. These results indicated that activation of the premotor cortex during word reading relies on the access of specific action concepts.

  11. Increase in physical activities in kindergarten children with cerebral palsy by employing MaKey-MaKey-based task systems.

    PubMed

    Lin, Chien-Yu; Chang, Yu-Ming

    2014-09-01

    In this study, we employed Flash- and Scratch-based multimedia by using a MaKey-MaKey-based task system to increase the motivation level of children with cerebral palsy to perform physical activities. MaKey MaKey is a circuit board that converts physical touch to a digital signal, which is interpreted by a computer as a keyboard message. In this study, we used conductive materials to control this interaction. This study followed single-case design using ABAB models in which A indicated the baseline and B indicated the intervention. The experiment period comprised 1 month and a half. The experimental results demonstrated that in the case of two kindergarten children with cerebral palsy, their scores were considerably increased during the intervention phrases. The developmental applications of the results are also discussed.

  12. Activation Patterns throughout the Word Processing Network of L1-dominant Bilinguals Reflect Language Similarity and Language Decisions.

    PubMed

    Oganian, Yulia; Conrad, Markus; Aryani, Arash; Spalek, Katharina; Heekeren, Hauke R

    2015-11-01

    A crucial aspect of bilingual communication is the ability to identify the language of an input. Yet, the neural and cognitive basis of this ability is largely unknown. Moreover, it cannot be easily incorporated into neuronal models of bilingualism, which posit that bilinguals rely on the same neural substrates for both languages and concurrently activate them even in monolingual settings. Here we hypothesized that bilinguals can employ language-specific sublexical (bigram frequency) and lexical (orthographic neighborhood size) statistics for language recognition. Moreover, we investigated the neural networks representing language-specific statistics and hypothesized that language identity is encoded in distributed activation patterns within these networks. To this end, German-English bilinguals made speeded language decisions on visually presented pseudowords during fMRI. Language attribution followed lexical neighborhood sizes both in first (L1) and second (L2) language. RTs revealed an overall tuning to L1 bigram statistics. Neuroimaging results demonstrated tuning to L1 statistics at sublexical (occipital lobe) and phonological (temporoparietal lobe) levels, whereas neural activation in the angular gyri reflected sensitivity to lexical similarity to both languages. Analysis of distributed activation patterns reflected language attribution as early as in the ventral stream of visual processing. We conclude that in language-ambiguous contexts visual word processing is dominated by L1 statistical structure at sublexical orthographic and phonological levels, whereas lexical search is determined by the structure of both languages. Moreover, our results demonstrate that language identity modulates distributed activation patterns throughout the reading network, providing a key to language identity representations within this shared network.

  13. Damage to temporo-parietal cortex decreases incidental activation of thematic relations during spoken word comprehension.

    PubMed

    Mirman, Daniel; Graziano, Kristen M

    2012-07-01

    Both taxonomic and thematic semantic relations have been studied extensively in behavioral studies and there is an emerging consensus that the anterior temporal lobe plays a particularly important role in the representation and processing of taxonomic relations, but the neural basis of thematic semantics is less clear. We used eye tracking to examine incidental activation of taxonomic and thematic relations during spoken word comprehension in participants with aphasia. Three groups of participants were tested: neurologically intact control participants (N=14), individuals with aphasia resulting from lesions in left hemisphere BA 39 and surrounding temporo-parietal cortex regions (N=7), and individuals with the same degree of aphasia severity and semantic impairment and anterior left hemisphere lesions (primarily inferior frontal gyrus and anterior temporal lobe) that spared BA 39 (N=6). The posterior lesion group showed reduced and delayed activation of thematic relations, but not taxonomic relations. In contrast, the anterior lesion group exhibited longer-lasting activation of taxonomic relations and did not differ from control participants in terms of activation of thematic relations. These results suggest that taxonomic and thematic semantic knowledge are functionally and neuroanatomically distinct, with the temporo-parietal cortex playing a particularly important role in thematic semantics.

  14. Exercise and Activity: Key Elements in the Management of OI

    MedlinePlus

    ... in both children and adults. Research indicates that physical activity is important because it promotes: general health through cardiovascular fitness mental alertness weight control improved sleep quality ...

  15. Words Matter: A Semantic Differential Study of Recreation, Leisure, Play, Activity, and Sport

    ERIC Educational Resources Information Center

    Schlag, Paul A.; Yoder, Daniel G.; Sheng, Zhaohui

    2015-01-01

    Beyond the standard definitions found in the dictionary, words commonly used in the recreation field have subtle, yet powerful connotations of which senders and receivers of information may not be consciously aware. These words elicit different conscious and subconscious reactions that likely bear significant consequences for recreation agencies…

  16. Parafoveal Processing of Transposed-Letter Words and Nonwords: Evidence against Parafoveal Lexical Activation

    ERIC Educational Resources Information Center

    Johnson, Rebecca L.; Dunne, Maxine D.

    2012-01-01

    The current experiments explored the parafoveal processing of transposed-letter (TL) neighbors by using an eye-movement-contingent boundary change paradigm. In Experiment 1 readers received a parafoveal preview of a target word (e.g., "calm") that was either (1) identical to the target word ("calm"), (2) a TL-neighbor ("clam"), or (3) a…

  17. Models of spoken-word recognition.

    PubMed

    Weber, Andrea; Scharenborg, Odette

    2012-05-01

    All words of the languages we know are stored in the mental lexicon. Psycholinguistic models describe in which format lexical knowledge is stored and how it is accessed when needed for language use. The present article summarizes key findings in spoken-word recognition by humans and describes how models of spoken-word recognition account for them. Although current models of spoken-word recognition differ considerably in the details of implementation, there is general consensus among them on at least three aspects: multiple word candidates are activated in parallel as a word is being heard, activation of word candidates varies with the degree of match between the speech signal and stored lexical representations, and activated candidate words compete for recognition. No consensus has been reached on other aspects such as the flow of information between different processing levels, and the format of stored prelexical and lexical representations. WIREs Cogn Sci 2012, 3:387-401. doi: 10.1002/wcs.1178 For further resources related to this article, please visit the WIREs website.

  18. Feature Statistics Modulate the Activation of Meaning During Spoken Word Processing.

    PubMed

    Devereux, Barry J; Taylor, Kirsten I; Randall, Billi; Geertzen, Jeroen; Tyler, Lorraine K

    2016-03-01

    Understanding spoken words involves a rapid mapping from speech to conceptual representations. One distributed feature-based conceptual account assumes that the statistical characteristics of concepts' features--the number of concepts they occur in (distinctiveness/sharedness) and likelihood of co-occurrence (correlational strength)--determine conceptual activation. To test these claims, we investigated the role of distinctiveness/sharedness and correlational strength in speech-to-meaning mapping, using a lexical decision task and computational simulations. Responses were faster for concepts with higher sharedness, suggesting that shared features are facilitatory in tasks like lexical decision that require access to them. Correlational strength facilitated responses for slower participants, suggesting a time-sensitive co-occurrence-driven settling mechanism. The computational simulation showed similar effects, with early effects of shared features and later effects of correlational strength. These results support a general-to-specific account of conceptual processing, whereby early activation of shared features is followed by the gradual emergence of a specific target representation.

  19. High-frequency neural activity predicts word parsing in ambiguous speech streams.

    PubMed

    Kösem, Anne; Basirat, Anahita; Azizi, Leila; van Wassenhove, Virginie

    2016-12-01

    During speech listening, the brain parses a continuous acoustic stream of information into computational units (e.g., syllables or words) necessary for speech comprehension. Recent neuroscientific hypotheses have proposed that neural oscillations contribute to speech parsing, but whether they do so on the basis of acoustic cues (bottom-up acoustic parsing) or as a function of available linguistic representations (top-down linguistic parsing) is unknown. In this magnetoencephalography study, we contrasted acoustic and linguistic parsing using bistable speech sequences. While listening to the speech sequences, participants were asked to maintain one of the two possible speech percepts through volitional control. We predicted that the tracking of speech dynamics by neural oscillations would not only follow the acoustic properties but also shift in time according to the participant's conscious speech percept. Our results show that the latency of high-frequency activity (specifically, beta and gamma bands) varied as a function of the perceptual report. In contrast, the phase of low-frequency oscillations was not strongly affected by top-down control. Whereas changes in low-frequency neural oscillations were compatible with the encoding of prelexical segmentation cues, high-frequency activity specifically informed on an individual's conscious speech percept.

  20. Individual differences in oscillatory brain activity in response to varying attentional demands during a word recall and oculomotor dual task

    PubMed Central

    Kwon, Gusang; Lim, Sanghyun; Kim, Min-Young; Kwon, Hyukchan; Lee, Yong-Ho; Kim, Kiwoong; Lee, Eun-Ju; Suh, Minah

    2015-01-01

    Every day, we face situations that involve multi-tasking. How our brain utilizes cortical resources during multi-tasking is one of many interesting research topics. In this study, we tested whether a dual-task can be differentiated in the neural and behavioral responses of healthy subjects with varying degree of working memory capacity (WMC). We combined word recall and oculomotor tasks because they incorporate common neural networks including the fronto-parietal (FP) network. Three different types of oculomotor tasks (eye fixation, Fix-EM; predictive and random smooth pursuit eye movement, P-SPEM and R-SPEM) were combined with two memory load levels (low-load: five words, high-load: 10 words) for a word recall task. Each of those dual-task combinations was supposed to create varying cognitive loads on the FP network. We hypothesize that each dual-task requires different cognitive strategies for allocating the brain’s limited cortical resources and affects brain oscillation of the FP network. In addition, we hypothesized that groups with different WMC will show differential neural and behavioral responses. We measured oscillatory brain activity with simultaneous MEG and EEG recordings and behavioral performance by word recall. Prominent frontal midline (FM) theta (4–6 Hz) synchronization emerged in the EEG of the high-WMC group experiencing R-SPEM with high-load conditions during the early phase of the word maintenance period. Conversely, significant parietal upper alpha (10–12 Hz) desynchronization was observed in the EEG and MEG of the low-WMC group experiencing P-SPEM under high-load conditions during the same period. Different brain oscillatory patterns seem to depend on each individual’s WMC and varying attentional demands from different dual-task combinations. These findings suggest that specific brain oscillations may reflect different strategies for allocating cortical resources during combined word recall and oculomotor dual-tasks. PMID:26175681

  1. Active Inhibition of a Distractor Word: The Distractor Precue Benefit in the Stroop Color-Naming Task

    ERIC Educational Resources Information Center

    Chao, Hsuan-Fu

    2011-01-01

    The current study investigated attentional control through active inhibition of the identity of the distractor. Adapting a Stroop paradigm, the distractor word was presented in advance and made to disappear, followed by the presentation of a Stroop stimulus. Participants were instructed to inhibit the distractor in order to reduce its…

  2. Two Words, One Meaning: Evidence of Automatic Co-Activation of Translation Equivalents

    PubMed Central

    Dimitropoulou, Maria; Duñabeitia, Jon Andoni; Carreiras, Manuel

    2011-01-01

    Research on the processing of translations offers important insights on how bilinguals negotiate the representation of words from two languages in one mind and one brain. Evidence so far has shown that translation equivalents effectively activate each other as well as their shared concept even when translations lack of any formal overlap (i.e., non-cognates) and even when one of them is presented subliminally, namely under masked priming conditions. In the lexical decision studies testing masked translation priming effects with unbalanced bilinguals a remarkably stable pattern emerges: larger effects in the dominant (L1) to the non-dominant (L2) translation direction, than vice versa. Interestingly, this asymmetry vanishes when simultaneous and balanced bilinguals are tested, suggesting that the linguistic profile of the bilinguals could be determining the pattern of cross-language lexico-semantic activation across the L2 learning trajectory. The present study aims to detect whether L2 proficiency is the critical variable rendering the otherwise asymmetric cross-language activation of translations obtained in the lexical decision task into symmetric. Non-cognate masked translation priming effects were examined with three groups of Greek (L1)–English (L2) unbalanced bilinguals, differing exclusively at their level of L2 proficiency. Although increased L2 proficiency led to improved overall L2 performance, masked translation priming effects were virtually identical across the three groups, yielding in all cases significant but asymmetric effects (i.e., larger effects in the L1 → L2 than in the L2 → L1 translation direction). These findings show that proficiency does not modulate masked translation priming effects at intermediate levels, and that a native-like level of L2 proficiency is needed for symmetric effects to emerge. They furthermore, pose important constraints on the operation of the mechanisms underlying the development of cross

  3. Functional activation studies of word processing in the recovery from aphasia.

    PubMed

    Zahn, Roland; Schwarz, Michael; Huber, Walter

    2006-06-01

    Some reviews on theories of recovery in aphasia put an emphasis on neural network models based on empirical data from evoked-potentials in aphasia as an approach to mapping recovery of cognitive function to neural structure. We will focus here on what we call an "anatomical" approach to look at recovery in aphasia. "Anatomical" theories of recovery stated by classical aphasiologists have contributed to the understanding of language representations in the human brain. But many aspects of these theories can only be investigated by using modern techniques of lesion analysis, psychometric assessment and functional imaging. Whereas structure-function relations have been primarily established by looking for the association of deficit symptoms with certain lesions, functional activation methods offer a means to study more directly the functional anatomy of recovered or retained functions in neuropsychological patients. To falsify or build up anatomical theories of recovery we will propose a stepwise approach of inference. The methodological pitfalls of this approach will be discussed by focussing on anatomical hypotheses of semantic word comprehension and its impairment and recovery in aphasia.

  4. Activeness as a key to counter democratic balance

    NASA Astrophysics Data System (ADS)

    Qian, Shen; Liu, Yijun; Galam, Serge

    2015-08-01

    According to the classic Galam model of opinion dynamics, each agent participates at each update of an opinion interaction. While the scheme gives everyone the same chance to influence others, in reality, social activity and influence vary considerably from one agent to another. To account for such a feature, we introduce a new individual attribute-"activeness"-which makes some agents more inclined than others at engaging in local discussions. To enhance the corresponding effect, opinion updates are shifted from all-out agent interaction cycles to few agent interaction cycles. Using dynamic analysis and simulations the resulting model is found to exhibit a "Minority Counteroffensive" phenomenon, which under some initial conditions makes the minority to win the opinion competition despite a threshold tipping point at fifty percent. The associated probabilistic phenomenon persists in the case "activeness" is held equal for all agents. The effect of "opinion leaders" is also investigated. Indeed, a leader is an inflexible agent, i.e., an agent who does not change opinion. The results reveal that two opinion leaders with moderate social influence may have a stronger effect than one opinion leader with a strong social influence. The model may shed a new light to the understanding of opinion formation and public voting.

  5. Keys to active ageing: new communication technologies and lifelong learning.

    PubMed

    Díaz-López, M Del Pilar; López-Liria, Remedios; Aguilar-Parra, José M; Padilla-Góngora, David

    2016-01-01

    The purpose of this study is to describe the creation and implementation of an ICT education program for the elderly in various Active Participation Centers in Almería (Spain), assessing its impact on quality of life. From a randomized sample of 200 individuals over the age of 55. Results reveal a high degree of participant satisfaction (76.6 %), as well as improvements in quality of life as compared to the control group after the 3 month program health factor: p = 0.004; leisure and activity factor: p = 0.001; Satisfaction with Life Factor: p < 0.001. The analysis conducted to determine the influence of age and gender on quality of life indicates that there are statistically significant differences in regards to age (the younger groups had higher scores) and gender (the males). This study may serve to facilitate similar works that promotes on-going education in different locations and across the lifespan.

  6. Language Non-Selective Activation of Orthography during Spoken Word Processing in Hindi-English Sequential Bilinguals: An Eye Tracking Visual World Study

    ERIC Educational Resources Information Center

    Mishra, Ramesh Kumar; Singh, Niharika

    2014-01-01

    Previous psycholinguistic studies have shown that bilinguals activate lexical items of both the languages during auditory and visual word processing. In this study we examined if Hindi-English bilinguals activate the orthographic forms of phonological neighbors of translation equivalents of the non target language while listening to words either…

  7. Parker Lecture - Prominences: the key to understanding solar activity

    NASA Astrophysics Data System (ADS)

    Karpen, Judith T.

    2011-05-01

    Prominences are spectacular manifestations of both quiescent and eruptive solar activity. The largest examples can be seen with the naked eye during eclipses, making prominences among the first solar features to be described and catalogued. Steady improvements in temporal and spatial resolution from both ground- and space-based instruments have led us to recognize how complex and dynamic these majestic structures really are. Their distinguishing characteristics - cool knots and threads suspended in the hot corona, alignment along inversion lines in the photospheric magnetic field within highly sheared filament channels, and a tendency to disappear through eruption - offer vital clues as to their origin and dynamic evolution. Interpreting these clues has proven to be contentious, however, leading to fundamentally different models that address the basic questions: What is the magnetic structure supporting prominences, and how does so much cool, dense plasma appear in the corona? Despite centuries of increasingly detailed observations, the magnetic and plasma structures in prominences are poorly known. Routine measurements of the vector magnetic field in and around prominences have become possible only recently, while long-term monitoring of the underlying filament-channel formation process remains scarce. The process responsible for prominence mass is equally difficult to establish, although we have long known that the chromosphere is the only plausible source. As I will discuss, however, the motions and locations of prominence material can be used to trace the coronal field, thus defining the magnetic origins of solar eruptions. A combination of observations, theory, and numerical modeling must be used to determine whether any of the competing theories accurately represents the physics of prominences. I will discuss the criteria for a successful prominence model, compare the leading models, and present in detail one promising, comprehensive scenario for prominence

  8. The emotional importance of key: do Beatles songs written in different keys convey different emotional tones?

    PubMed

    Whissel, R; Whissel, C

    2000-12-01

    Lyrics from 155 songs written by the Lennon-McCartney team were scored using the Dictionary of Affect in Language. Resultant scores (pleasantness, activation, and imagery of words) were compared across key signatures using one way analyses of variance. Words from songs written in minor keys were less pleasant and less active than those from songs written in major keys. Words from songs written in the key of F scored extremely low on all three measures. Lyrics from the keys of C, D, and G were relatively active in tone. Results from Dictionary scoring were compared with assignments of character to keys made more than one century ago and with current musicians' opinions.

  9. How does Arabic orthographic connectivity modulate brain activity during visual word recognition: an ERP study.

    PubMed

    Taha, Haitham; Ibrahim, Raphiq; Khateb, Asaid

    2013-04-01

    One of the unique features of the Arabic orthography that differentiates it from many other alphabetical ones is the fact that most letters connect obligatorily to each other. Hence, these letters change their forms according to the location in the word (i.e. beginning, middle, or end), leading to the suggestion that connectivity adds a visual load which negatively impacts reading in Arabic. In this study, we investigated the effects of the orthographic connectivity on the time course of early brain electric responses during the visual word recognition. For this purpose, we collected event-related potentials (ERPs) from adult skilled readers while performing a lexical decision task using fully connected (Cw), partially connected and non-connected words (NCw). Reaction times variance was higher and accuracy was lower in NCw compared to Cw words. ERPs analysis revealed significant amplitude and latency differences between Cw and NCw at posterior electrodes during the N170 component which implied the temporo-occipital areas. Our findings show that instead of slowing down reading, orthographic connectivity in Arabic skilled readers seems to impact positively the reading process already during the early stages of word recognition. These results are discussed in relation to previous observations in the literature.

  10. "Word Power" (Vocabulary Development).

    ERIC Educational Resources Information Center

    Voorhees, Roxy

    Containing numerous vocabulary-building activities and exercises, this guidebook is designed to help elementary students learn to manipulate language as they gain concrete experiences with words, increase their "word power," and have fun. The activities described involve dictionary games, synonyms, "saidonyms" (alternatives for…

  11. Word of the Day

    ERIC Educational Resources Information Center

    Abrar-Ul-Hassan, Shahid

    2010-01-01

    Independent lexical development initiatives empower and equip language learners with skills to boost their lexical repertoires. Language instructors can train learners to be autonomous word learners. A sample activity, namely word of the day, is presented in this article. The activity is an independent lexical learning task, which aims to develop…

  12. Impact of changed positive and negative task-related brain activity on word-retrieval in aging

    PubMed Central

    Meinzer, M.; Seeds, L.; Flaisch, T.; Harnish, S.; Cohen, M.L.; McGregor, K.; Conway, T.; Benjamin, M.; Crosson, B.

    2010-01-01

    Previous functional imaging studies that compared activity patterns in older and younger adults during non-linguistic tasks found evidence for two phenomena: older participants usually show more pronounced task-related positive activity in the brain hemisphere that is not dominant for the task and less pronounced negative task-related activity in temporo-parietal and midline brain regions. The combined effects of these phenomena and the impact on word-retrieval, however, have not yet been assessed. We used functional magnetic resonance imaging to explore task-related positive (active task > baseline) and negative activity (baseline > active task) during semantic and phonemic verbal fluency tasks. Increased right-frontal positive activity during the semantic task and reduced negative activity in the right hemisphere during both tasks was associated with reduced performance in older subjects. No substantial relationship between changes in positive and negative activity was observed in the older participants, pointing towards two partially independent but potentially co-occurring processes. Underlying causes of the observed functional network inefficiency during word-retrieval in older adults need to be determined in the future. PMID:20696496

  13. Automatic Semantic Activation of Embedded Words: Is There a ''Hat'' in ''That''

    ERIC Educational Resources Information Center

    Bowers, J.S.; Davis, C.J.; Hanley, D.A.

    2005-01-01

    Participants semantically categorized target words that contain subsets (Experiment 1; e.g., target=hatch, subset=hat) or that are parts of supersets (Experiment 2; e.g., target=bee, superset=beer). In both experiments, the targets were categorized in a congruent condition (in which the subset-superset was associated with the same response, e.g.,…

  14. Feature Statistics Modulate the Activation of Meaning during Spoken Word Processing

    ERIC Educational Resources Information Center

    Devereux, Barry J.; Taylor, Kirsten I.; Randall, Billi; Geertzen, Jeroen; Tyler, Lorraine K.

    2016-01-01

    Understanding spoken words involves a rapid mapping from speech to conceptual representations. One distributed feature-based conceptual account assumes that the statistical characteristics of concepts' features--the number of concepts they occur in ("distinctiveness/sharedness") and likelihood of co-occurrence ("correlational…

  15. Identifying Key Features of Effective Active Learning: The Effects of Writing and Peer Discussion

    ERIC Educational Resources Information Center

    Linton, Debra L.; Pangle, Wiline M.; Wyatt, Kevin H.; Powell, Karli N.; Sherwood, Rachel E.

    2014-01-01

    We investigated some of the key features of effective active learning by comparing the outcomes of three different methods of implementing active-learning exercises in a majors introductory biology course. Students completed activities in one of three treatments: discussion, writing, and discussion + writing. Treatments were rotated weekly between…

  16. Physically Active Adults: An Analysis of the Key Variables That Keep Them Moving

    ERIC Educational Resources Information Center

    Downs, Andrew

    2016-01-01

    Background: A large proportion of adults are insufficiently physically active, and researchers have yet to determine the factors that enable individuals to maintain adequate levels of physical activity throughout adulthood. Purpose: This study sought to identify the key variables linked with consistent physical activity in adulthood as elucidated…

  17. The effect of encoding strategies on medial temporal lobe activations during the recognition of words: an event-related fMRI study.

    PubMed

    Tsukiura, Takashi; Mochizuki-Kawai, Hiroko; Fujii, Toshikatsu

    2005-04-01

    It is known that manipulation of the encoding strategy affects behavioral and activation data during later retrieval. In the present fMRI study, we examined brain activity during the recognition of words encoded using three different strategies formed by the combination of two factors of relational and self-performed processes. The first encoding strategy involved subjects learning words using both relational and self-performed processes (R+S+). In the second, subjects learned words using only a relational process (R+S-). In the third, subjects learned words without using either process (R-S-). During fMRI after encoding, subjects were randomly presented with words encoded previously and with new words (New) and were required to judge whether or not the word presented had been previously encoded. The fMRI experiment was performed with the event-related design. Compared to New, activation of the left medial temporal lobe (MTL) occurred during the recognition of words encoded using R+S+ and R+S-, whereas right MTL activations only occurred with the R+S+ strategy. ROI analysis for the bilateral hippocampus and parahippocampal gyrus showed a linear increase in left MTL activity (hippocampus and parahippocampal gyrus) during the recognition of words encoded with the R-S-, R+S-, to R+S+, whereas right MTL activity (parahippocampal gyrus) was only increased with the R+S+ strategy. The findings suggest that the left and right MTL structures may contribute differentially to the processes involved in the recognition of stimuli and that these differential activities may depend on the encoding strategies formed by the two factors of relational and self-performed processes.

  18. Chippy's Computer Words.

    ERIC Educational Resources Information Center

    Willing, Kathlene R.; Girard, Suzanne

    Intended for young children just becoming familiar with computers, this naming book introduces and reinforces new computer vocabulary and concepts. The 20 words are presented alphabetically, along with illustrations, providing room for different activities in which children can match and name the pictures and words. The 20 vocabulary items are…

  19. Evidence for the Activation of Sensorimotor Information during Visual Word Recognition: The Body-Object Interaction Effect

    ERIC Educational Resources Information Center

    Siakaluk, Paul D.; Pexman, Penny M.; Aguilera, Laura; Owen, William J.; Sears, Christopher R.

    2008-01-01

    We examined the effects of sensorimotor experience in two visual word recognition tasks. Body-object interaction (BOI) ratings were collected for a large set of words. These ratings assess perceptions of the ease with which a human body can physically interact with a word's referent. A set of high BOI words (e.g., "mask") and a set of low BOI…

  20. Word form Encoding in Chinese Word Naming and Word Typing

    ERIC Educational Resources Information Center

    Chen, Jenn-Yeu; Li, Cheng-Yi

    2011-01-01

    The process of word form encoding was investigated in primed word naming and word typing with Chinese monosyllabic words. The target words shared or did not share the onset consonants with the prime words. The stimulus onset asynchrony (SOA) was 100 ms or 300 ms. Typing required the participants to enter the phonetic letters of the target word,…

  1. Signal Words

    MedlinePlus

    ... product. The signal word can be ei- ther: DANGER,WARNING or CAUTION. Products with the DANGER signal word are the most toxic. Products with ... causes moderate eye or skin irritation. 2,4 DANGER means that the pesticide product is highly toxic ...

  2. Semantic priming in schizophrenia: an examination of spreading activation using word pronunciation and multiple SOAs.

    PubMed

    Barch, D M; Cohen, J D; Servan-Schreiber, D; Steingard, S; Cohen, J D; Steinhauer, S S; van Kammen, D P

    1996-11-01

    Semantic priming in word pronunciation was examined at 5 stimulus onset asynchronies (SOAs) in 75 medicated and 25 unmedicated people with schizophrenia (SCZ) and in 10 depressed and 28 normal controls. At SOAs < 950 ms, SCZ displayed priming similar to that of normal and depressed controls. At the 950-ms SOA, SCZ displayed less priming than controls. Medication dosage, but not conceptual disorganization scores, was positively associated with priming at SOAs < 950 ms. These results suggest that prior reports of enhanced priming in schizophrenia may have been confounded by methodological problems and that automatic priming processes operate normally in SCZ. The failure of SCZ to display significant priming at the 950-ms SOA is consistent with a hypothesized disturbance in higher level processes.

  3. Word Links: A Strategy for Developing Word Knowledge

    ERIC Educational Resources Information Center

    Yopp, Ruth Helen

    2007-01-01

    Word Links, an effective strategy for developing students' vocabulary, is based on four principles. It provides contextual and definitional information; offers repeated exposure to words and opportunities to practice them; encourages students to think about relationships among word meanings; and involves active engagement in learning tasks. Yopp…

  4. The Temporal Dynamics of Ambiguity Resolution: Evidence from Spoken-Word Recognition

    ERIC Educational Resources Information Center

    Dahan, Delphine; Gaskell, M. Gareth

    2007-01-01

    Two experiments examined the dynamics of lexical activation in spoken-word recognition. In both, the key materials were pairs of onset-matched picturable nouns varying in frequency. Pictures associated with these words, plus two distractor pictures were displayed. A gating task, in which participants identified the picture associated with…

  5. Word Processing.

    ERIC Educational Resources Information Center

    McWilliams, Peter

    1982-01-01

    Describes the kinds of computer equipment needed for a personal word processing system. The characteristics and capabilities of specific devices, including keyboards, printers, and disk drives, are discussed. (JL)

  6. 5 CFR 591.241 - What are the key activities of the COLA Advisory Committees?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SERVICE REGULATIONS ALLOWANCES AND DIFFERENTIALS Cost-of-Living Allowance and Post Differential-Nonforeign Areas Program Administration § 591.241 What are the key activities of the COLA Advisory Committees? (a) The COLA Advisory Committees may— (1) Advise and assist OPM in planning living-cost surveys;...

  7. Preschool Children's Foreign Language Vocabulary Learning by Embodying Words through Physical Activity and Gesturing

    ERIC Educational Resources Information Center

    Toumpaniari, Konstantina; Loyens, Sofie; Mavilidi, Myrto-Foteini; Paas, Fred

    2015-01-01

    Research has demonstrated that physical activity involving gross motor activities can lead to better cognitive functioning and higher academic achievement scores. In addition, research within the theoretical framework of embodied cognition has shown that embodying knowledge through the use of more subtle motor activities, such as task-relevant…

  8. How vertical hand movements impact brain activity elicited by literally and metaphorically related words: an ERP study of embodied metaphor

    PubMed Central

    Bardolph, Megan; Coulson, Seana

    2014-01-01

    Embodied metaphor theory suggests abstract concepts are metaphorically linked to more experientially basic ones and recruit sensorimotor cortex for their comprehension. To test whether words associated with spatial attributes reactivate traces in sensorimotor cortex, we recorded EEG from the scalp of healthy adults as they read words while performing a concurrent task involving either upward- or downward- directed arm movements. ERPs were time-locked to words associated with vertical space—either literally (ascend, descend) or metaphorically (inspire, defeat)—as participants made vertical movements that were either congruent or incongruent with the words. Congruency effects emerged 200–300 ms after word onset for literal words, but not until after 500 ms post-onset for metaphorically related words. Results argue against a strong version of embodied metaphor theory, but support a role for sensorimotor simulation in concrete language. PMID:25566041

  9. Adenosine monophosphate-activated kinase and its key role in catabolism: structure, regulation, biological activity, and pharmacological activation.

    PubMed

    Krishan, Sukriti; Richardson, Des R; Sahni, Sumit

    2015-01-01

    Adenosine monophosphate-activated protein kinase (AMPK) is a cellular energy sensor, which once activated, plays a role in several processes within the cell to restore energy homeostasis. The protein enhances catabolic pathways, such as β-oxidation and autophagy, to generate ATP, and inhibits anabolic processes that require energy, including fatty acid, cholesterol, and protein synthesis. Due to its key role in the regulation of critical cellular pathways, deregulation of AMPK is associated with the pathology of many diseases, including cancer, Wolff-Parkinson-White syndrome, neurodegenerative disorders, diabetes, and metabolic syndrome. In fact, AMPK is a target of some pharmacological agents implemented in the treatment of diabetes (metformin and thiazolidinediones) as well as other naturally derived products, such as berberine, which is used in traditional medicine. Due to its critical role in the cell and the pathology of several disorders, research into developing AMPK as a therapeutic target is becoming a burgeoning and exciting field of pharmacological research. A profound understanding of the regulation and activity of AMPK would enhance its development as a promising therapeutic target.

  10. Prediction of Geomagnetic Activity and Key Parameters in High-Latitude Ionosphere-Basic Elements

    NASA Technical Reports Server (NTRS)

    Lyatsky, W.; Khazanov, G. V.

    2007-01-01

    Prediction of geomagnetic activity and related events in the Earth's magnetosphere and ionosphere is an important task of the Space Weather program. Prediction reliability is dependent on the prediction method and elements included in the prediction scheme. Two main elements are a suitable geomagnetic activity index and coupling function -- the combination of solar wind parameters providing the best correlation between upstream solar wind data and geomagnetic activity. The appropriate choice of these two elements is imperative for any reliable prediction model. The purpose of this work was to elaborate on these two elements -- the appropriate geomagnetic activity index and the coupling function -- and investigate the opportunity to improve the reliability of the prediction of geomagnetic activity and other events in the Earth's magnetosphere. The new polar magnetic index of geomagnetic activity and the new version of the coupling function lead to a significant increase in the reliability of predicting the geomagnetic activity and some key parameters, such as cross-polar cap voltage and total Joule heating in high-latitude ionosphere, which play a very important role in the development of geomagnetic and other activity in the Earth s magnetosphere, and are widely used as key input parameters in modeling magnetospheric, ionospheric, and thermospheric processes.

  11. Cognitive processing of body and appearance words as a function of thin-ideal internalization and schematic activation.

    PubMed

    Cassin, Stephanie E; von Ranson, Kristin M; Whiteford, Simone

    2008-09-01

    To better understand how women at risk of body image disturbance respond when their body concerns are activated, we examined attentional and memory biases in undergraduate women with high thin-ideal internalization, an identified risk factor for eating disorders, following priming of body and appearance concerns. Female undergraduates (N=186) viewed photos of either sports cars or attractive swimsuit models, then completed the Lexical Decision Test, a word recall test, and questionnaires assessing thin-ideal internalization and eating disorder symptomatology. High thin-ideal internalizers did not exhibit cognitive biases predicted by cognitive models of eating disorders, even when their body and appearance concerns were primed by exposure to attractive models. Converging evidence suggests that high-risk non-clinical samples rarely exhibit cognitive biases characteristic of individuals with eating disorders, and, in fact, may actually incorporate ideal appearance into their schemas and preferentially attend to attractive stimuli.

  12. Word List Memory Predicts Everyday Function and Problem-Solving in the Elderly: Results from the ACTIVE Cognitive Intervention Trial

    PubMed Central

    Gross, Alden L.; Rebok, George W.; Unverzagt, Frederick W.; Willis, Sherry L.; Brandt, Jason

    2011-01-01

    Data from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial (N=2,802) were analyzed to examine whether word list learning predicts future everyday functioning. Using stepwise random effects modeling, measures from the modified administrations of the Hopkins Verbal Learning Test (HVLT) and the Auditory Verbal Learning Test (AVLT) were independently predictive of everyday IADL functioning, problem-solving, and psychomotor speed. Associations between memory scores and everyday functioning outcomes remained significant across follow-up intervals spanning five years. HVLT total recall score was consistently the strongest predictor of each functional outcome. Results suggest that verbal memory measures are uniquely associated with both current and future functioning and that specific verbal memory tests like the HVLT and AVLT have important clinical utility in predicting future functional ability among older adults. PMID:21069610

  13. A novel active contour model for unsupervised low-key image segmentation

    NASA Astrophysics Data System (ADS)

    Mei, Jiangyuan; Si, Yulin; Karimi, Hamid; Gao, Huijun

    2013-06-01

    Unsupervised image segmentation is greatly useful in many vision-based applications. In this paper, we aim at the unsupervised low-key image segmentation. In low-key images, dark tone dominates the background, and gray level distribution of the foreground is heterogeneous. They widely exist in the areas of space exploration, machine vision, medical imaging, etc. In our algorithm, a novel active contour model with the probability density function of gamma distribution is proposed. The flexible gamma distribution gives a better description for both of the foreground and background in low-key images. Besides, an unsupervised curve initialization method is designed, which helps to accelerate the convergence speed of curve evolution. The experimental results demonstrate the effectiveness of the proposed algorithm through comparison with the CV model. Also, one real-world application based on our approach is described in this paper.

  14. ClueConnect: a word array game to promote student comprehension of key terminology in an introductory anatomy and physiology course.

    PubMed

    Burleson, Kathryn M; Olimpo, Jeffrey T

    2016-06-01

    The sheer amount of terminology and conceptual knowledge required for anatomy and physiology can be overwhelming for students. Educational games are one approach to reinforce such knowledge. In this activity, students worked collaboratively to review anatomy and physiology concepts by creating arrays of descriptive tiles to define a term. Once guessed, students located the structure or process within diagrams of the body. The game challenged students to think about course vocabulary in novel ways and to use their collective knowledge to get their classmates to guess the terms. Comparison of pretest/posttest/delayed posttest data revealed that students achieved statistically significant learning gains for each unit after playing the game, and a survey of student perceptions demonstrated that the game was helpful for learning vocabulary as well as fun to play. The game is easily adaptable for a variety of lower- and upper-division courses.

  15. Automatic phonological activation during visual word recognition in bilingual children: A cross-language masked priming study in grades 3 and 5.

    PubMed

    Sauval, Karinne; Perre, Laetitia; Duncan, Lynne G; Marinus, Eva; Casalis, Séverine

    2017-02-01

    Previous masked priming research has shown automatic phonological activation during visual word recognition in monolingual skilled adult readers. Activation also occurs across languages in bilingual adult readers, suggesting that the activation of phonological representations is not language specific. Less is known about developing readers. First, it is unclear whether there is automatic phonological activation during visual word recognition among children in general. Second, no empirical data exist on whether the activation of phonological representations is language specific or not in bilingual children. The current study investigated these issues in bilingual third and fifth graders using cross-language phonological masked priming in a lexical decision task. Targets were French words, and primes were English pseudowords of three types: (a) phonological primes, which share phonological information with the target beginning (e.g., dee-DIMANCHE [Sunday], pronounced /di:/-/dimãʃ/); (b) orthographic control primes, which control for letters shared by the phonological prime and target (e.g., d) and their position (e.g., doo-DIMANCHE, pronounced /du:/-/dimãʃ/); and (c) unrelated primes, which share no phonological or orthographic information with the target beginning (e.g., pow-DIMANCHE, pronounced /paʊ/-/dimãʃ/). Significant phonological priming was observed, suggesting that (a) phonological representations are rapidly and automatically activated by print during visual word recognition from Grade 3 onward and that (b) the activation of phonological representations is not language specific in bilingual children.

  16. Brief Report: Brain Activation to Social Words in a Sedated Child with Autism

    ERIC Educational Resources Information Center

    Carmody, Dennis P.; Moreno, Rosanne; Mars, Audrey E.; Seshadri, Kapila; Lambert, George H.; Lewis, Michael

    2007-01-01

    A functional magnetic resonance imaging (fMRI) study was performed on a 4-year-old girl with autism. While sedated, she listened to three utterances (numbers, hello, her own first name) played through headphones. Based on analyses of the fMRI data, the amount of total brain activation varied with the content of the utterance. The greatest volume…

  17. Increased motor preparation activity during fluent single word production in DS: A correlate for stuttering frequency and severity.

    PubMed

    Vanhoutte, Sarah; Santens, Patrick; Cosyns, Marjan; van Mierlo, Pieter; Batens, Katja; Corthals, Paul; De Letter, Miet; Van Borsel, John

    2015-08-01

    Abnormal speech motor preparation is suggested to be a neural characteristic of stuttering. One of the neurophysiological substrates of motor preparation is the contingent negative variation (CNV). The CNV is an event-related, slow negative potential that occurs between two defined stimuli. Unfortunately, CNV tasks are rarely studied in developmental stuttering (DS). Therefore, the present study aimed to evaluate motor preparation in DS by use of a CNV task. Twenty five adults who stutter (AWS) and 35 fluent speakers (FS) were included. They performed a picture naming task while an electro-encephalogram was recorded. The slope of the CNV was evaluated at frontal, central and parietal electrode sites. In addition, a correlation analysis was performed with stuttering severity and frequency measures. There was a marked increase in CNV slope in AWS as compared to FS. This increase was observed over the entire scalp with respect to stimulus onset, and only over the right hemisphere with respect to lip movement onset. Moreover, strong positive correlations were found between CNV slope and stuttering frequency and severity. As the CNV is known to reflect the activity in the basal ganglia-thalamo-cortical-network, the present findings confirm an increased activation of this loop during speech motor preparation in stuttering. The more a person stutters, the more neurons of this cortical-subcortical network seem to be activated. Because this increased CNV slope was observed during fluent single word production, it is discussed whether or not this observation refers to a successful compensation strategy.

  18. Magical Words

    ERIC Educational Resources Information Center

    Strauch-Nelson, Wendy

    2007-01-01

    Prompted by a parent's comment that indicated a desire for her elementary-age children to learn the elements and principles of design in their art class, the author set out to enrich her own understanding and appreciation of the language used in the art room. Looking at word origins helps students appreciate the significance of art and craft in…

  19. Sarbalap! Words.

    ERIC Educational Resources Information Center

    Cantu, Virginia, Comp.; And Others

    Prepared by bilingual teacher aide students, this glossary provides the Spanish translation of about 1,300 English words used in the bilingual classroom. Intended to serve as a handy reference for teachers, teacher aides, and students, the glossary can also be used in teacher training programs as a vocabulary builder for future bilingual teachers…

  20. High Neuromagnetic Activation in the Left Prefrontal and Frontal Cortices Correlates with Better Memory Performance for Abstract Words

    ERIC Educational Resources Information Center

    Chen, Tzu-Ching; Lin, Yung-Yang

    2012-01-01

    The present study aimed to clarify the spatiotemporal characteristics of memory processing for abstract and concrete words. Neuromagnetic responses to memory encoding and recognition tasks of abstract and concrete nouns were obtained in 18 healthy adults using a whole-head neuromagnetometer. During memory encoding, abstract words elicited larger…

  1. Using the Word Processor in Writing Groups.

    ERIC Educational Resources Information Center

    Melia, Josie

    Writing groups can use word processors or microcomputers in many different types of writing activities. Four hour-long sessions at a word processor with the help of a skilled word processing tutor have been found to be sufficient to provide a working knowledge of word processing. When two or three students enrolled in a writing class are assigned…

  2. Modeling the N400 ERP component as transient semantic over-activation within a neural network model of word comprehension.

    PubMed

    Cheyette, Samuel J; Plaut, David C

    2016-11-18

    The study of the N400 event-related brain potential has provided fundamental insights into the nature of real-time comprehension processes, and its amplitude is modulated by a wide variety of stimulus and context factors. It is generally thought to reflect the difficulty of semantic access, but formulating a precise characterization of this process has proved difficult. Laszlo and colleagues (Laszlo & Plaut, 2012; Laszlo & Armstrong, 2014) used physiologically constrained neural networks to model the N400 as transient over-activation within semantic representations, arising as a consequence of the distribution of excitation and inhibition within and between cortical areas. The current work extends this approach to successfully model effects on both N400 amplitudes and behavior of word frequency, semantic richness, repetition, semantic and associative priming, and orthographic neighborhood size. The account is argued to be preferable to one based on "implicit semantic prediction error" (Rabovsky & McRae, 2014) for a number of reasons, the most fundamental of which is that the current model actually produces N400-like waveforms in its real-time activation dynamics.

  3. Identification of Key Residues Determining Isomerohydrolase Activity of Human RPE65*

    PubMed Central

    Takahashi, Yusuke; Moiseyev, Gennadiy; Ma, Jian-xing

    2014-01-01

    RPE65 is the retinoid isomerohydrolase that converts all-trans-retinyl ester to 11-cis-retinol, a key reaction in the retinoid visual cycle. We have previously reported that cone-dominant chicken RPE65 (cRPE65) shares 90% sequence identity with human RPE65 (hRPE65) but exhibits substantially higher isomerohydrolase activity than that of bovine RPE65 or hRPE65. In this study, we sought to identify key residues responsible for the higher enzymatic activity of cRPE65. Based on the amino acid sequence comparison of mammalian and other lower vertebrates' RPE65, including cone-dominant chicken, 8 residues of hRPE65 were separately replaced by their counterparts of cRPE65 using site-directed mutagenesis. The enzymatic activities of cRPE65, hRPE65, and its mutants were measured by in vitro isomerohydrolase activity assay, and the retinoid products were analyzed by HPLC. Among the mutants analyzed, two single point mutants, N170K and K297G, and a double mutant, N170K/K297G, of hRPE65 exhibited significantly higher catalytic activity than WT hRPE65. Further, when an amino-terminal fragment (Met1–Arg33) of the N170K/K297G double mutant of hRPE65 was replaced with the corresponding cRPE65 fragment, the isomerohydrolase activity was further increased to a level similar to that of cRPE65. This finding contributes to the understanding of the structural basis for isomerohydrolase activity. This highly efficient human isomerohydrolase mutant can be used to improve the efficacy of RPE65 gene therapy for retinal degeneration caused by RPE65 mutations. PMID:25112876

  4. Key factor in rice husk ash/CaO sorbent for high flue gas desulfurization activity

    SciTech Connect

    Irvan Dahlan; Keat Teong Lee; Azlina Harun Kamaruddin; Abdul Rahman Mohamed

    2006-10-01

    Siliceous materials such as rice husk ash (RHA) have potential to be utilized as high performance sorbents for the flue gas desulfurization process in small-scale industrial boilers. This study presents findings on identifying the key factor for high desulfurization activity in sorbents prepared from RHA. Initially, a systematic approach using central composite rotatable design was used to develop a mathematical model that correlates the sorbent preparation variables to the desulfurization activity of the sorbent. The sorbent preparation variables studied are hydration period, x{sub 1} (6-16 h), amount of RHA, x{sub 2} (5-15 g), amount of CaO, x{sub 3} (2-6 g), amount of water, x{sub 4} (90-110 mL), and hydration temperature, x{sub 5} (150-250{sup o}C). The mathematical model developed was subjected to statistical tests and the model is adequate for predicting the SO{sub 2} desulfurization activity of the sorbent within the range of the sorbent preparation variables studied. Based on the model, the amount of RHA, amount of CaO, and hydration period used in the preparation step significantly influenced the desulfurization activity of the sorbent. The ratio of RHA and CaO used in the preparation mixture was also a significant factor that influenced the desulfurization activity of the sorbent. A RHA to CaO ratio of 2.5 leads to the formation of specific reactive species in the sorbent that are believed to be the key factor responsible for high desulfurization activity in the sorbent. Other physical properties of the sorbent such as pore size distribution and surface morphology were found to have insignificant influence on the desulfurization activity of the sorbent. 31 refs., 5 figs., 3 tabs.

  5. Does "Word Coach" Coach Words?

    ERIC Educational Resources Information Center

    Cobb, Tom; Horst, Marlise

    2011-01-01

    This study reports on the design and testing of an integrated suite of vocabulary training games for Nintendo[TM] collectively designated "My Word Coach" (Ubisoft, 2008). The games' design is based on a wide range of learning research, from classic studies on recycling patterns to frequency studies of modern corpora. Its general usage…

  6. Dynamics of activation of semantically similar concepts during spoken word recognition.

    PubMed

    Mirman, Daniel; Magnuson, James S

    2009-10-01

    Semantic similarity effects provide critical insight into the organization of semantic knowledge and the nature of semantic processing. In the present study, we examined the dynamics of semantic similarity effects by using the visual world eyetracking paradigm. Four objects were shown on a computer monitor, and participants were instructed to click on a named object, during which time their gaze position was recorded. The likelihood of fixating competitor objects was predicted by the degree of semantic similarity to the target concept. We found reliable, graded competition that depended on degree of target-competitor similarity, even for distantly related items for which priming has not been found in previous priming studies. Time course measures revealed a consistently earlier fixation peak for near semantic neighbors relative to targets. Computational investigations with an attractor dynamical model, a spreading activation model, and a decision model revealed that a combination of excitatory and inhibitory mechanisms is required to obtain such peak timing, providing new constraints on models of semantic processing.

  7. Biochemical evidence of key residues for the activation and autoprocessing of tomato type II metacaspase.

    PubMed

    Wen, Shuai; Ma, Qiu-Min; Zhang, Ya-Li; Yang, Ji-Ping; Zhao, Guang-Hua; Fu, Da-Qi; Luo, Yun-Bo; Qu, Gui-Qin

    2013-08-19

    To investigate the autolysis pattern and activation of metacaspase in higher plants, the biochemical characteristics of purified recombinant type II metacaspase (LeMCA1) from tomato were explored. Western blotting analysis indicated that four cleaved bands were formed; two N-terminal fragments and two C-terminal fragments. N-terminal sequencing confirmed that LeMCA1 cleaves at Lys223 and Arg332. Site mutants indicated that catalytic Cys139, cleaved Lys223, Arg332 and predicted calcium binding Asp116/Asp117 are the key residues that are responsible for its Ca²⁺ and pH dependent activation. The cleavage of the full-size fragment seemed crucial for the activation of LeMCA1 in vitro.

  8. Identifying key features of effective active learning: the effects of writing and peer discussion.

    PubMed

    Linton, Debra L; Pangle, Wiline M; Wyatt, Kevin H; Powell, Karli N; Sherwood, Rachel E

    2014-01-01

    We investigated some of the key features of effective active learning by comparing the outcomes of three different methods of implementing active-learning exercises in a majors introductory biology course. Students completed activities in one of three treatments: discussion, writing, and discussion + writing. Treatments were rotated weekly between three sections taught by three different instructors in a full factorial design. The data set was analyzed by generalized linear mixed-effect models with three independent variables: student aptitude, treatment, and instructor, and three dependent (assessment) variables: change in score on pre- and postactivity clicker questions, and coding scores on in-class writing and exam essays. All independent variables had significant effects on student performance for at least one of the dependent variables. Students with higher aptitude scored higher on all assessments. Student scores were higher on exam essay questions when the activity was implemented with a writing component compared with peer discussion only. There was a significant effect of instructor, with instructors showing different degrees of effectiveness with active-learning techniques. We suggest that individual writing should be implemented as part of active learning whenever possible and that instructors may need training and practice to become effective with active learning.

  9. Learning about Science Graphs and Word Games. Superific Science Book V. A Good Apple Science Activity Book for Grades 5-8+.

    ERIC Educational Resources Information Center

    Conway, Lorraine

    This packet of student materials contains a variety of worksheet activities dealing with science graphs and science word games. These reproducible materials deal with: (1) bar graphs; (2) line graphs; (3) circle graphs; (4) pictographs; (5) histograms; (6) artgraphs; (7) designing your own graphs; (8) medical prefixes; (9) color prefixes; (10)…

  10. Phonological Words and Stuttering on Function Words.

    ERIC Educational Resources Information Center

    Au-Yeung, James; Howell, Peter; Pilgrim, Lesley

    1998-01-01

    Stuttering on function words was examined in 51 children and adults who stutter. Stuttering rate was a function of age (children stuttered more on function words), position (function words in early positions in utterances were more likely to be stuttered), and on whether the function word occurred before or after the single content word.…

  11. The SEDIBUD (Sediment Budgets in Cold Environments) Programme: Current activities and future key tasks

    NASA Astrophysics Data System (ADS)

    Beylich, A. A.; Lamoureux, S. F.; Decaulne, A.

    2012-04-01

    Projected climate change in cold regions is expected to alter melt season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. Similarly, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active layer depths. These effects will undoubtedly change surface environments in cold regions and alter the fluxes of sediments, nutrients and solutes, but the absence of quantitative data and coordinated process monitoring and analysis to understand the sensitivity of the Earth surface environment is acute in cold climate environments. The International Association of Geomorphologists (I.A.G./A.I.G.)SEDIBUD (Sediment Budgets in Cold Environments) Programme was formed in 2005 to address this existing key knowledge gap. SEDIBUD currently has about 400 members worldwide and the Steering Committee of this international programme is composed of ten scientists from eight different countries: Achim A. Beylich (Chair) (Norway), Armelle Decaulne (Secretary) (France), John C. Dixon (USA), Scott F. Lamoureux (Vice-Chair) (Canada), John F. Orwin (Canada), Jan-Christoph Otto (Austria), Irina Overeem (USA), Thorsteinn Saemundsson (Iceland), Jeff Warburton (UK), Zbigniew Zwolinski (Poland). The central research question of this global group of scientists is to: Assess and model the contemporary sedimentary fluxes in cold climates, with emphasis on both particulate and dissolved components. Initially formed as European Science Foundation (ESF) Network SEDIFLUX (2004-2006), SEDIBUD has further expanded to a global group of researchers with field research sites located in polar and alpine regions in the northern and southern hemisphere. Research carried out at each of the close to 50 defined SEDIBUD key test sites varies by programme, logistics and available resources, but typically represent interdisciplinary collaborations of

  12. Activity of key enzymes in glucose catabolism during the growth and metacyclogenesis of Leishmania infantum.

    PubMed

    Louassini, M; Foulquié, M R; Benítez, R; Adroher, F J

    1999-04-01

    This paper follows the development in the activity of the key enzymes of glycolysis and dehydrogenases of the pentose phosphate shunt throughout the in vitro growth and metacyclogenesis of two human strains of Leishmania infantum - one visceral (VL) and the other cutaneous (CL) - together with changes in the glucose, ammonium, and proton concentrations in the culture medium. In the first stage, ammonium was generated and no glucose was consumed. Later on, all the glucose was consumed and, finally, ammonium was generated again. The ammonium concentration increased 16- and 21-fold in cultures of VL and CL strains, respectively. The activities of the glycosomal enzymes hexokinase and phosphofructokinase differed in each strain, always being higher in CL than in VL and increasing throughout the culture period in CL while decreasing in VL. This probably indicates a different capability to adapt to the culture medium conditions. The activities of the pentose phosphate shunt enzymes examined indicate that 6-phosphogluconate dehydrogenase is possibly a rate-limiting enzyme for this pathway. Pyruvate kinase is a cytosolic control enzyme of glycolysis in trypanosomatids, and its activity decreased throughout the growth and differentiation of both strains of L. infantum, as occurs in other trypanosomatids. It was also observed that glucose catabolism was more active in the cutaneous strain than in the visceral one.

  13. Phosphatase activity in relation to key litter and soil properties in mature subtropical forests in China.

    PubMed

    Hou, Enqing; Chen, Chengrong; Wen, Dazhi; Liu, Xian

    2015-05-15

    Phosphatase-mediated phosphorus (P) mineralization is one of the critical processes in biogeochemical cycling of P and determines soil P availability in forest ecosystems; however, the regulation of soil phosphatase activity remains elusive. This study investigated the potential extracellular activities of acid phosphomonoesterase (AcPME) and phosphodiesterase (PDE) and how they were related to key edaphic properties in the L horizon (undecomposed litter) and F/H horizon (fermented and humified litter) and the underlying mineral soil at the 0-15cm depth in eight mature subtropical forests in China. AcPME activity decreased significantly in the order of F/H horizon>L horizon>mineral soil horizon, while the order for PDE activity was L horizon=F/H horizon>mineral soil horizon. AcPME (X axis) and PDE (Y axis) activities were positively correlated in all horizons with significantly higher slope in the L and F/H horizons than in the mineral soil horizon. Both AcPME and PDE activities were positively related to microbial biomass C, moisture content and water-holding capacity in the L horizon, and were positively related to soil C:P, N:P and C:N ratios and fine root (diameter≤2mm) biomass in the mineral soil horizon. Both enzyme activities were also interactively affected by forest and horizon, partly due to the interactive effect of forest and horizon on microbial biomass. Our results suggest that modulator(s) of the potential extracellular activity of phosphatases vary with horizon, depending on the relative C, P and water availability of the horizon.

  14. Word Domain Disambiguation via Word Sense Disambiguation

    SciTech Connect

    Sanfilippo, Antonio P.; Tratz, Stephen C.; Gregory, Michelle L.

    2006-06-04

    Word subject domains have been widely used to improve the perform-ance of word sense disambiguation al-gorithms. However, comparatively little effort has been devoted so far to the disambiguation of word subject do-mains. The few existing approaches have focused on the development of al-gorithms specific to word domain dis-ambiguation. In this paper we explore an alternative approach where word domain disambiguation is achieved via word sense disambiguation. Our study shows that this approach yields very strong results, suggesting that word domain disambiguation can be ad-dressed in terms of word sense disam-biguation with no need for special purpose algorithms.

  15. Magnesium impacts myosin V motor activity by altering key conformational changes in the mechanochemical cycle.

    PubMed

    Trivedi, Darshan V; Muretta, Joseph M; Swenson, Anja M; Thomas, David D; Yengo, Christopher M

    2013-07-09

    We investigated how magnesium (Mg) impacts key conformational changes during the ADP binding/release steps in myosin V and how these alterations impact the actomyosin mechanochemical cycle. The conformation of the nucleotide binding pocket was examined with our established FRET system in which myosin V labeled with FlAsH in the upper 50 kDa domain participates in energy transfer with mant labeled nucleotides. We examined the maximum actin-activated ATPase activity of MV FlAsH at a range of free Mg concentrations (0.1-9 mM) and found that the highest activity occurs at low Mg (0.1-0.3 mM), while there is a 50-60% reduction in activity at high Mg (3-9 mM). The motor activity examined with the in vitro motility assay followed a similar Mg-dependence, and the trend was similar with dimeric myosin V. Transient kinetic FRET studies of mantdADP binding/release from actomyosin V FlAsH demonstrate that the transition between the weak and strong actomyosin.ADP states is coupled to movement of the upper 50 kDa domain and is dependent on Mg with the strong state stabilized by Mg. We find that the kinetics of the upper 50 kDa conformational change monitored by FRET correlates well with the ATPase and motility results over a wide range of Mg concentrations. Our results suggest the conformation of the upper 50 kDa domain is highly dynamic in the Mg free actomyosin.ADP state, which is in agreement with ADP binding being entropy driven in the absence of Mg. Overall, our results demonstrate that Mg is a key factor in coupling the nucleotide- and actin-binding regions. In addition, Mg concentrations in the physiological range can alter the structural transition that limits ADP dissociation from actomyosin V, which explains the impact of Mg on actin-activated ATPase activity and in vitro motility.

  16. Words are not things

    PubMed Central

    Moore, J.

    2000-01-01

    On a traditional view, words are the fundamental units of verbal behavior. They are independent, autonomous things that symbolically represent or refer to other independent, autonomous things, often in some other dimension. Ascertaining what those other things are constitutes determining the meaning of a word. On a behavior-analytic view, verbal behavior is ongoing, functional operant activity occasioned by antecedent factors and reinforced by its consequences, particularly consequences that are mediated by other members of the same verbal community. Functional relations rather than structure select the response unit. The behavior-analytic point of view clarifies such important contemporary issues in psychology as (a) the role of scientific theories and explanations, (b) educational practices, and (c) equivalence classes, so that there is no risk of strengthening the traditional view that words are things that symbolically represent other things. PMID:22477219

  17. First Words and First Memories

    ERIC Educational Resources Information Center

    Morrison, Catriona M.; Conway, Martin A.

    2010-01-01

    In two experiments autobiographical memories from childhood were recalled to cue words naming common objects, locations, activities and emotions. Participants recalled their earliest specific memory associated with each word and dated their age at the time of the remembered event. A striking and specific finding emerged: age of earliest memory was…

  18. Bilingual Reading of Compound Words

    ERIC Educational Resources Information Center

    Ko, In Yeong; Wang, Min; Kim, Say Young

    2011-01-01

    The present study investigated whether bilingual readers activate constituents of compound words in one language while processing compound words in the other language via decomposition. Two experiments using a lexical decision task were conducted with adult Korean-English bilingual readers. In Experiment 1, the lexical decision of real English…

  19. Casein kinase 1δ activity: a key element in the zebrafish circadian timing system.

    PubMed

    Smadja Storz, Sima; Tovin, Adi; Mracek, Philipp; Alon, Shahar; Foulkes, Nicholas S; Gothilf, Yoav

    2013-01-01

    Zebrafish have become a popular model for studies of the circadian timing mechanism. Taking advantage of its rapid development of a functional circadian clock and the availability of light-entrainable clock-containing cell lines, much knowledge has been gained about the circadian clock system in this species. However, the post-translational modifications of clock proteins, and in particular the phosphorylation of PER proteins by Casein kinase I delta and epsilon (CK1δ and CK1ε), have so far not been examined in the zebrafish. Using pharmacological inhibitors for CK1δ and CK1ε, a pan-CK1δ/ε inhibitor PF-670462, and a CK1ε -selective inhibitor PF-4800567, we show that CK1δ activity is crucial for the functioning of the circadian timing mechanism of zebrafish, while CK1ε plays a minor role. The CK1δ/ε inhibitor disrupted circadian rhythms of promoter activity in the circadian clock-containing zebrafish cell line, PAC-2, while the CK1ε inhibitor had no effect. Zebrafish larvae that were exposed to the CK1δ/ε inhibitor showed no rhythms of locomotor activity while the CK1ε inhibitor had only a minor effect on locomotor activity. Moreover, the addition of the CK1δ/ε inhibitor disrupted rhythms of aanat2 mRNA expression in the pineal gland. The pineal gland is considered to act as a central clock organ in fish, delivering a rhythmic hormonal signal, melatonin, which is regulated by AANAT2 enzymatic activity. Therefore, CK1δ plays a key role in the circadian timing system of the zebrafish. Furthermore, the effect of CK1δ inhibition on rhythmic locomotor activity may reflect its effect on the function of the central clock in the pineal gland as well as its regulation of peripheral clocks.

  20. Key clinical activities for quality asthma care. Recommendations of the National Asthma Education and Prevention Program.

    PubMed

    Williams, Seymour G; Schmidt, Diana K; Redd, Stephen C; Storms, William

    2003-03-28

    In 1997, the National Asthma Education and Prevention Program (NAEPP), coordinated by the National Heart, Lung, and Blood Institute, published the second Expert Panel Report (EPR-2): Guidelines for the Diagnosis and Management of Asthma (National Heart, Lung, and Blood Institute, National Asthma Education and Prevention Program. Expert Panel Report 2: Guidelines for the diagnosis and management of asthma. Bethesda MD: US Department of Health and Human Services, National Institutes of Health, 1997; publication no. 97-4051. Available at http://www.nhlbi.nih.gov/guidelines/ asthma/asthgdln.pdf). Subsequently, the NAEPP Expert Panel identified key questions regarding asthma management that were submitted to an evidence practice center of the Agency for Healthcare Research and Quality to conduct a systematic review of the evidence. The resulting evidence report was used by the Expert Panel to update recommendations for clinical practice on selected topics. These recommendations (EPR-Update 2002) were published in 2002. (National Heart, Lung, and Blood Institute, National Asthma Education and Prevention Program. Guidelines for the diagnosis and management of asthma--update on selected topics 2002. J Allergy Clin Immunol 2002;110[November 2002, part 2]. Available at http://www.nhlbi.nih.gov/guidelines/asthma/index.htm). To improve the implementation of these guidelines, a working group of the Professional Education Subcommittee of the NAEPP extracted key clinical activities that should be considered as essential for quality asthma care in accordance with the EPR-2 guidelines and the EPR-Update 2002. The purpose was to develop a report that would help purchasers and planners of health care define the activities that are important to quality asthma care, particularly in reducing symptoms and preventing exacerbations, and subsequently reducing the overall national burden of illness and death from asthma. This report is intended to help employer health benefits managers and

  1. Sustained impact of community-based physical activity interventions: key elements for success

    PubMed Central

    2013-01-01

    Background Compelling evidence supports the cost effectiveness and potential impact of physical activity on chronic disease prevention and health promotion. Quality of evidence is one piece, but certainly not the sole determinant of whether public health interventions, physical activity focused or otherwise, achieve their full potential for impact. Health promotion at both population and community levels must progress beyond health intervention models that isolate individuals from social, environmental, and political systems of influence. We offer a critical evaluation of lessons learned from two successful research initiatives to provide insights as to how health promotion research contributes to sustained impact. We highlight factors key to success including the theoretical and methodological integration of: i) a social ecological approach; ii) participatory action research (PAR) methods; and iii) an interdisciplinary team. Methods To identify and illustrate the key elements of our success we layered an evaluation of steps taken atop a review of relevant literature. Results In the school-based case study (Action Schools! BC), the success of our approach included early and sustained engagement with a broad cross-section of stakeholders, establishing partnerships across sectors and at different levels of government, and team members across multiple disciplines. In the neighbourhood built environment case study, the three domains guided our approach through study design and team development, and the integration of older adults’ perspectives into greenway design plans. In each case study we describe how elements of the domains serve as a guide for our work. Conclusion To sustain and maximize the impact of community-based public health interventions we propose the integration of elements from three domains of research that acknowledge the interplay between social, environmental and poilitical systems of influence. We emphasize that a number of key factors determine

  2. The Question of Teaching Vocabulary: Which Words? In What Ways?

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D., Ed.

    2013-01-01

    Recognizing the importance of vocabulary for comprehension, Wilhelm asks two key questions: "which words do I teach and how should I teach them?" Through years of trial and error, Wilhelm has adopted these principles to answer "which words": teach "important" words students will see and use again; words necessary to conceptual understanding; words…

  3. Unlocking Doors without Keys: Activation of Src by Truncated C-terminal Intracellular Receptor Tyrosine Kinases Lacking Tyrosine Kinase Activity

    PubMed Central

    Mezquita, Belén; Mezquita, Pau; Pau, Montserrat; Mezquita, Jovita; Mezquita, Cristóbal

    2014-01-01

    One of the best examples of the renaissance of Src as an open door to cancer has been the demonstration that just five min of Src activation is sufficient for transformation and also for induction and maintenance of cancer stem cells [1]. Many tyrosine kinase receptors, through the binding of their ligands, become the keys that unlock the structure of Src and activate its oncogenic transduction pathways. Furthermore, intracellular isoforms of these receptors, devoid of any tyrosine kinase activity, still retain the ability to unlock Src. This has been shown with a truncated isoform of KIT (tr-KIT) and a truncated isoform of VEGFR-1 (i21-VEGFR-1), which are intracellular and require no ligand binding, but are nonetheless able to activate Src and induce cell migration and invasion of cancer cells. Expression of the i21-VEGFR-1 is upregulated by the Notch signaling pathway and repressed by miR-200c and retinoic acid in breast cancer cells. Both Notch inhibitors and retinoic acid have been proposed as potential therapies for invasive breast cancer. PMID:24709904

  4. Selective visual attention to emotional words: Early parallel frontal and visual activations followed by interactive effects in visual cortex.

    PubMed

    Schindler, Sebastian; Kissler, Johanna

    2016-10-01

    Human brains spontaneously differentiate between various emotional and neutral stimuli, including written words whose emotional quality is symbolic. In the electroencephalogram (EEG), emotional-neutral processing differences are typically reflected in the early posterior negativity (EPN, 200-300 ms) and the late positive potential (LPP, 400-700 ms). These components are also enlarged by task-driven visual attention, supporting the assumption that emotional content naturally drives attention. Still, the spatio-temporal dynamics of interactions between emotional stimulus content and task-driven attention remain to be specified. Here, we examine this issue in visual word processing. Participants attended to negative, neutral, or positive nouns while high-density EEG was recorded. Emotional content and top-down attention both amplified the EPN component in parallel. On the LPP, by contrast, emotion and attention interacted: Explicit attention to emotional words led to a substantially larger amplitude increase than did explicit attention to neutral words. Source analysis revealed early parallel effects of emotion and attention in bilateral visual cortex and a later interaction of both in right visual cortex. Distinct effects of attention were found in inferior, middle and superior frontal, paracentral, and parietal areas, as well as in the anterior cingulate cortex (ACC). Results specify separate and shared mechanisms of emotion and attention at distinct processing stages. Hum Brain Mapp 37:3575-3587, 2016. © 2016 Wiley Periodicals, Inc.

  5. Regional Changes in Word-Production Laterality after a Naming Treatment Designed to Produce a Rightward Shift in Frontal Activity

    ERIC Educational Resources Information Center

    Crosson, Bruce; Moore, Anna Bacon; McGregor, Keith M.; Chang, Yu-Ling; Benjamin, Michelle; Gopinath, Kaundinya; Sherod, Megan E.; Wierenga, Christina E.; Peck, Kyung K.; Briggs, Richard W.; Rothi, Leslie J. Gonzalez; White, Keith D.

    2009-01-01

    Five nonfluent aphasia patients participated in a picture-naming treatment that used an intention manipulation (opening a box and pressing a button on a device in the box with the left hand) to initiate naming trials and was designed to re-lateralize word production mechanisms from the left to the right frontal lobe. To test the underlying…

  6. Automatic Activation of Phonological Code during Visual Word Recognition in Children: A Masked Priming Study in Grades 3 and 5

    ERIC Educational Resources Information Center

    Sauval, Karinne; Perre, Laetitia; Casalis, Séverine

    2017-01-01

    The present study aimed to investigate the development of automatic phonological processes involved in visual word recognition during reading acquisition in French. A visual masked priming lexical decision experiment was carried out with third, fifth graders and adult skilled readers. Three different types of partial overlap between the prime and…

  7. Autocrine abscisic acid plays a key role in quartz-induced macrophage activation.

    PubMed

    Magnone, Mirko; Sturla, Laura; Jacchetti, Emanuela; Scarfì, Sonia; Bruzzone, Santina; Usai, Cesare; Guida, Lucrezia; Salis, Annalisa; Damonte, Gianluca; De Flora, Antonio; Zocchi, Elena

    2012-03-01

    Inhalation of quartz induces silicosis, a lung disease where alveolar macrophages release inflammatory mediators, including prostaglandin-E(2) (PGE(2)) and tumor necrosis factor α (TNF-α). Here we report the pivotal role of abscisic acid (ABA), a recently discovered human inflammatory hormone, in silica-induced activation of murine RAW264.7 macrophages and of rat alveolar macrophages (AMs). Stimulation of both RAW264.7 cells and AMs with quartz induced a significant increase of ABA release (5- and 10-fold, respectively), compared to untreated cells. In RAW264.7 cells, autocrine ABA released after quartz stimulation sequentially activates the plasma membrane receptor LANCL2 and NADPH oxidase, generating a Ca(2+) influx resulting in NFκ B nuclear translocation and PGE(2) and TNF-α release (3-, 2-, and 3.5-fold increase, respectively, compared to control, unstimulated cells). Quartz-stimulated RAW264.7 cells silenced for LANCL2 or preincubated with a monoclonal antibody against ABA show an almost complete inhibition of NFκ B nuclear translocation and PGE(2) and TNF-α release compared to controls electroporated with a scramble oligonucleotide or preincubated with an unrelated antibody. AMs showed similar early and late ABA-induced responses as RAW264.7 cells. These findings identify ABA and LANCL2 as key mediators in quartz-induced inflammation, providing possible new targets for antisilicotic therapy.

  8. Sublethal Effects of Insecticide Exposure on Megacopta cribraria (Fabricius) Nymphs: Key Biological Traits and Acetylcholinesterase Activity

    PubMed Central

    Miao, Jin; Reisig, Dominic D.; Li, Guoping; Wu, Yuqing

    2016-01-01

    Megacopta cribraria F. (Hemiptera: Plataspidae), the kudzu bug, is an invasive insect pest of U.S. soybean. At present, insecticide application is the primary and most effective control option for M. cribraria. In this study, the potential effects of sublethal and low-lethal concentrations (LC10 and LC40) of three common insecticides on key biological traits and acetylcholinesterase (AChE) activity of the treated nymphal stage of insect were assessed. The results show that the sublethal concentration of imidacloprid significantly reduced adult emergence rate of M. cribraria. A low-lethal concentration of imidacloprid significantly increased nymphal development time, but significantly decreased adult emergence rate and adult longevity. Both sublethal and low-lethal concentrations of acephate caused an increase in nymphal development time and a reduction in adult emergence rate and adult longevity. Fecundity of females was significantly reduced only by exposure to low-lethal concentrations of acephate. Sublethal and low-lethal concentrations of bifenthrin increased nymphal development time, but significantly decreased adult emergence rate. In addition, we found that the AChE activity of M. cribraria was significantly increased only by LC40 imidacloprid, but strongly inhibited by acephate. PMID:27638957

  9. The Key Role of Sulfation and Branching on Fucoidan Antitumor Activity.

    PubMed

    Oliveira, Catarina; Ferreira, Andreia S; Novoa-Carballal, Ramon; Nunes, Cláudia; Pashkuleva, Iva; Neves, Nuno M; Coimbra, Manuel A; Reis, Rui L; Martins, Albino; Silva, Tiago H

    2016-12-20

    There is an urgent need for antitumor bioactive agents with minimal or no side effects over normal adjacent cells. Fucoidan is a marine-origin polymer with known antitumor activity. However, there are still some concerns about its application due to the inconsistent experimental results, specifically its toxicity over normal cells and the mechanism behind its action. Herein, three fucoidan extracts (FEs) have been tested over normal and breast cancer cell lines. From cytotoxicity results, only one of the extracts shows selective antitumor behavior (at 0.2 mg mL(-1) ), despite similarities in sulfation degree and carbohydrates composition. Although the three FEs present different molecular weights, depolymerization of selected samples discarded Mw as the key factor in the antitumor activity. Significant differences in sulfates position and branching are observed, presenting FE 2 the higher branching degree. Based on all these experimental data, it is believed that these last two properties are the ones that influence the cytotoxic effects of fucoidan extracts.

  10. Is the time course of lexical activation and competition in spoken word recognition affected by adult aging? An event-related potential (ERP) study.

    PubMed

    Hunter, Cynthia R

    2016-10-01

    Adult aging is associated with decreased accuracy for recognizing speech, particularly in noisy backgrounds and for high neighborhood density words, which sound similar to many other words. In the current study, the time course of neighborhood density effects in young and older adults was compared using event-related potentials (ERP) and behavioral responses in a lexical decision task for spoken words and nonwords presented either in quiet or in noise. Target items sounded similar either to many or to few other words (neighborhood density) but were balanced for the frequency of their component sounds (phonotactic probability). Behavioral effects of density were similar across age groups, but the event-related potential effects of density differed as a function of age group. For young adults, density modulated the amplitude of both the N400 and the later P300 or late positive complex (LPC). For older adults, density modulated only the amplitude of the P300/LPC. Thus, spreading activation to the semantics of lexical neighbors, indexed by the N400 density effect, appears to be reduced or delayed in adult aging. In contrast, effects of density on P300/LPC amplitude were present in both age groups, perhaps reflecting attentional allocation to items that resemble few words in the mental lexicon. The results constitute the first evidence that ERP effects of neighborhood density are affected by adult aging. The age difference may reflect either a unitary density effect that is delayed by approximately 150ms in older adults, or multiple processes that are differentially affected by aging.

  11. Word, Words, Words: Ellul and the Mediocritization of Language

    ERIC Educational Resources Information Center

    Foltz, Franz; Foltz, Frederick

    2012-01-01

    The authors explore how technique via propaganda has replaced the word with images creating a mass society and limiting the ability of people to act as individuals. They begin by looking at how words affect human society and how they have changed over time. They explore how technology has altered the meaning of words in order to create a more…

  12. Geology is the Key to Explain Igneous Activity in the Mediterranean Area

    NASA Astrophysics Data System (ADS)

    Lustrino, M.

    2014-12-01

    Igneous activity in tectonically complex areas can be interpreted in many different ways, producing completely different petrogenetic models. Processes such as oceanic and continental subduction, lithospheric delamination, changes in subduction polarity, slab break-off and mantle plumes have all been advocated as causes for changes in plate boundaries and magma production, including rate and temporal distribution, in the circum-Mediterranean area. This region thus provides a natural laboratory to investigate a range of geodynamic and magmatic processes. Although many petrologic and tectonic models have been proposed, a number of highly controversial questions still remain. No consensus has yet been reached about the capacity of plate-tectonic processes to explain the origin and style of the magmatism. Similarly, there is still not consensus on the ability of geochemical and petrological arguments to reveal the geodynamic evolution of the area. The wide range of chemical and mineralogical magma compositions produced within and around the Mediterranean, from carbonatites to strongly silica-undersaturated silico-carbonatites and melilitites to strongly silica-oversaturated rhyolites, complicate models and usually require a large number of unconstrained assumptions. Can the calcalkaline-sodic alkaline transition be related to any common petrogenetic point? Is igneous activity plate-tectonic- (top-down) or deep-mantle-controlled (bottom-up)? Do the rare carbonatites and carbonate-rich igneous rocks derive from the deep mantle or a normal, CO2-bearing upper mantle? Do ultrapotassic compositions require continental subduction? Understanding chemically complex magmas emplaced in tectonically complex areas require open minds, and avoiding dogma and assumptions. Studying the geology and shallow dynamics, not speculating about the deep lower mantle, is the key to understanding the igneous activity.

  13. 3000 Instant Words.

    ERIC Educational Resources Information Center

    Sakiey, Elizabeth; Fry, Edward

    This book presents the 3,000 most frequently used words in rank and alphabetical orders. The words were derived from the American Heritage word list of the approximately 87,000 most frequent words in a count of 5 million running words sampled from a variety of elementary and secondary level curriculum materials, magazines, and books. The book…

  14. Hydrogenosome Metabolism Is the Key Target for Antiparasitic Activity of Resveratrol against Trichomonas vaginalis

    PubMed Central

    Mallo, Natalia; Lamas, Jesús

    2013-01-01

    Metronidazole (MDZ) and related 5-nitroimidazoles are the recommended drugs for treatment of trichomoniasis, a sexually transmitted disease caused by the protozoan parasite Trichomonas vaginalis. However, novel treatment options are needed, as recent reports have claimed resistance to these drugs in T. vaginalis isolates. In this study, we analyzed for the first time the in vitro effects of the natural polyphenol resveratrol (RESV) on T. vaginalis. At concentrations of between 25 and 100 μM, RESV inhibited the in vitro growth of T. vaginalis trophozoites; doses of 25 μM exerted a cytostatic effect, and higher doses exerted a cytotoxic effect. At these concentrations, RESV caused inhibition of the specific activity of a 120-kDa [Fe]-hydrogenase (Tvhyd). RESV did not affect Tvhyd gene expression and upregulated pyruvate-ferredoxin oxidoreductase (a hydrogenosomal enzyme) gene expression only at a high dose (100 μM). At doses of 50 to 100 μM, RESV also caused overexpression of heat shock protein 70 (Hsp70), a protective protein found in the hydrogenosome of T. vaginalis. The results demonstrate the potential of RESV as an antiparasitic treatment for trichomoniasis and suggest that the mechanism of action involves induction of hydrogenosomal dysfunction. In view of the results, we propose hydrogenosomal metabolism as a key target in the design of novel antiparasitic drugs. PMID:23478970

  15. Identification of guanine exchange factor key residues involved in exchange activity and Ras interaction.

    PubMed

    Camus, C; Hermann-Le Denmat, S; Jacquet, M

    1995-09-07

    We have carried out a functional analysis of the human HGRF55 exchange factor in the yeast Saccharomyces cerevisiae. Twelve residues conserved among most of all known guanine exchange factors (GEFs) have been independently changed to alanine. Taking advantage of the ability of Hgrf55p to replace the yeast Cdc25p exchange factor, and using the two-hybrid system with RAS2ala22 allele, we have identified key residues for the interaction with Ras and/or its activation. Substitution of arginine 392 to alanine leads to a complete loss of interaction with Ras, though the protein remains stable. Substitution of Asp266 or Arg359 to alanine results in inactive proteins at 39 degrees C, still able however to interact with Ras. The other charged-to-alanine substitutions led to no detectable phenotype when present alone but most of them dramatically increased the temperature sensitive phenotype observed with [Asp266Ala] substitution. Surprisingly, the cysteine to alanine substitution in the highly conserved PCVPF/Y motif proved to be without effect, suggesting that the sulfhydryl group is not essential for stability or interaction with Ras.

  16. Hydrogenosome metabolism is the key target for antiparasitic activity of resveratrol against Trichomonas vaginalis.

    PubMed

    Mallo, Natalia; Lamas, Jesús; Leiro, José M

    2013-06-01

    Metronidazole (MDZ) and related 5-nitroimidazoles are the recommended drugs for treatment of trichomoniasis, a sexually transmitted disease caused by the protozoan parasite Trichomonas vaginalis. However, novel treatment options are needed, as recent reports have claimed resistance to these drugs in T. vaginalis isolates. In this study, we analyzed for the first time the in vitro effects of the natural polyphenol resveratrol (RESV) on T. vaginalis. At concentrations of between 25 and 100 μM, RESV inhibited the in vitro growth of T. vaginalis trophozoites; doses of 25 μM exerted a cytostatic effect, and higher doses exerted a cytotoxic effect. At these concentrations, RESV caused inhibition of the specific activity of a 120-kDa [Fe]-hydrogenase (Tvhyd). RESV did not affect Tvhyd gene expression and upregulated pyruvate-ferredoxin oxidoreductase (a hydrogenosomal enzyme) gene expression only at a high dose (100 μM). At doses of 50 to 100 μM, RESV also caused overexpression of heat shock protein 70 (Hsp70), a protective protein found in the hydrogenosome of T. vaginalis. The results demonstrate the potential of RESV as an antiparasitic treatment for trichomoniasis and suggest that the mechanism of action involves induction of hydrogenosomal dysfunction. In view of the results, we propose hydrogenosomal metabolism as a key target in the design of novel antiparasitic drugs.

  17. Key Factors Influencing Rates of Heterotrophic Sulfate Reduction in Active Seafloor Hydrothermal Massive Sulfide Deposits

    PubMed Central

    Frank, Kiana L.; Rogers, Karyn L.; Rogers, Daniel R.; Johnston, David T.; Girguis, Peter R.

    2015-01-01

    Hydrothermal vents are thermally and geochemically dynamic habitats, and the organisms therein are subject to steep gradients in temperature and chemistry. To date, the influence of these environmental dynamics on microbial sulfate reduction has not been well constrained. Here, via multivariate experiments, we evaluate the effects of key environmental variables (temperature, pH, H2S, SO42−, DOC) on sulfate reduction rates and metabolic energy yields in material recovered from a hydrothermal flange from the Grotto edifice in the Main Endeavor Field, Juan de Fuca Ridge. Sulfate reduction was measured in batch reactions across a range of physico-chemical conditions. Temperature and pH were the strongest stimuli, and maximum sulfate reduction rates were observed at 50°C and pH 6, suggesting that the in situ community of sulfate-reducing organisms in Grotto flanges may be most active in a slightly acidic and moderate thermal/chemical regime. At pH 4, sulfate reduction rates increased with sulfide concentrations most likely due to the mitigation of metal toxicity. While substrate concentrations also influenced sulfate reduction rates, energy-rich conditions muted the effect of metabolic energetics on sulfate reduction rates. We posit that variability in sulfate reduction rates reflect the response of the active microbial consortia to environmental constraints on in situ microbial physiology, toxicity, and the type and extent of energy limitation. These experiments help to constrain models of the spatial contribution of heterotrophic sulfate reduction within the complex gradients inherent to seafloor hydrothermal deposits. PMID:26733984

  18. Regulation of sucrose metabolism in higher plants: localization and regulation of activity of key enzymes

    NASA Technical Reports Server (NTRS)

    Winter, H.; Huber, S. C.; Brown, C. S. (Principal Investigator)

    2000-01-01

    Sucrose (Suc) plays a central role in plant growth and development. It is a major end product of photosynthesis and functions as a primary transport sugar and in some cases as a direct or indirect regulator of gene expression. Research during the last 2 decades has identified the pathways involved and which enzymes contribute to the control of flux. Availability of metabolites for Suc synthesis and 'demand' for products of sucrose degradation are important factors, but this review specifically focuses on the biosynthetic enzyme sucrose-phosphate synthase (SPS), and the degradative enzymes, sucrose synthase (SuSy), and the invertases. Recent progress has included the cloning of genes encoding these enzymes and the elucidation of posttranslational regulatory mechanisms. Protein phosphorylation is emerging as an important mechanism controlling SPS activity in response to various environmental and endogenous signals. In terms of Suc degradation, invertase-catalyzed hydrolysis generally has been associated with cell expansion, whereas SuSy-catalyzed metabolism has been linked with biosynthetic processes (e.g., cell wall or storage products). Recent results indicate that SuSy may be localized in multiple cellular compartments: (1) as a soluble enzyme in the cytosol (as traditionally assumed); (2) associated with the plasma membrane; and (3) associated with the actin cytoskeleton. Phosphorylation of SuSy has been shown to occur and may be one of the factors controlling localization of the enzyme. The purpose of this review is to summarize some of the recent developments relating to regulation of activity and localization of key enzymes involved in sucrose metabolism in plants.

  19. T-2 toxin inhibits gene expression and activity of key steroidogenesis enzymes in mouse Leydig cells.

    PubMed

    Yang, Jian Ying; Zhang, Yong Fa; Meng, Xiang Ping; Li, Yuan Xiao; Ma, Kai Wang; Bai, Xue Fei

    2015-08-01

    T-2 toxin is one of the mycotoxins, a group of type A trichothecenes produced by several fungal genera including Fusarium species, which may lead to the decrease of the testosterone secretion in the primary Leydig cells derived from the mouse testis. The previous study demonstrated the effects of T-2 toxin through direct decrease of the testosterone biosynthesis in the primary Leydig cells derived from the mouse testis. In this study, we further examined the direct biological effects of T-2 toxin on steroidogenesis production, primarily in Leydig cells of mice. Mature mouse Leydig cells were purified by Percoll gradient centrifugation and the cell purity was determined by 3β-hydroxysteroid dehydrogenase (3β-HSD) staining. To examine T-2 toxin-induced testosterone secretion decrease, we measured the transcription levels of 3 key steroidogenic enzymes and 5 enzyme activities including 3β-HSD-1, P450scc, StAR, CYP17A1, and 17β-HSD in T-2 toxin/human chorionicgonadotropin (hCG) co-treated cells. Our previous study showed that T-2 toxin (10(-7) M, 10(-8) M and 10(-9) M) significantly suppressed hCG (10 ng/ml)-induced testosterone secretion. The studies demonstrated that the suppressive effect is correlated with the decreases in the levels of transcription of 3β-HSD-1, P450scc, and StAR (P<0.05) and also in enzyme activities of 3β-HSD-1, P450scc, StAR, CYP17A1, and 17β-HSD (P<0.05).

  20. Word Sorts for General Music Classes

    ERIC Educational Resources Information Center

    Cardany, Audrey Berger

    2015-01-01

    Word sorts are standard practice for aiding children in acquiring skills in English language arts. When included in the general music classroom, word sorts may aid students in acquiring a working knowledge of music vocabulary. The author shares a word sort activity drawn from vocabulary in John Lithgow's children's book "Never Play…

  1. Implicit phonological priming during visual word recognition.

    PubMed

    Wilson, Lisa B; Tregellas, Jason R; Slason, Erin; Pasko, Bryce E; Rojas, Donald C

    2011-03-15

    Phonology is a lower-level structural aspect of language involving the sounds of a language and their organization in that language. Numerous behavioral studies utilizing priming, which refers to an increased sensitivity to a stimulus following prior experience with that or a related stimulus, have provided evidence for the role of phonology in visual word recognition. However, most language studies utilizing priming in conjunction with functional magnetic resonance imaging (fMRI) have focused on lexical-semantic aspects of language processing. The aim of the present study was to investigate the neurobiological substrates of the automatic, implicit stages of phonological processing. While undergoing fMRI, eighteen individuals performed a lexical decision task (LDT) on prime-target pairs including word-word homophone and pseudoword-word pseudohomophone pairs with a prime presentation below perceptual threshold. Whole-brain analyses revealed several cortical regions exhibiting hemodynamic response suppression due to phonological priming including bilateral superior temporal gyri (STG), middle temporal gyri (MTG), and angular gyri (AG) with additional region of interest (ROI) analyses revealing response suppression in the left lateralized supramarginal gyrus (SMG). Homophone and pseudohomophone priming also resulted in different patterns of hemodynamic responses relative to one another. These results suggest that phonological processing plays a key role in visual word recognition. Furthermore, enhanced hemodynamic responses for unrelated stimuli relative to primed stimuli were observed in midline cortical regions corresponding to the default-mode network (DMN) suggesting that DMN activity can be modulated by task requirements within the context of an implicit task.

  2. Effect of urethane, dimethylnitrosamine, paraquat, and butylated hydroxytoluene on the activities of glycolytic key enzymes in mouse lung

    SciTech Connect

    Arany, I.; Rady, P.; Bojan, I.; Kertai, P.

    1981-12-01

    Effects of carcinogens and noncarcinogenic pulmonary toxicants on the activities of glycolytic key enzymes in the mouse lung were investigated. The carcinogens urethane (URTH) and dimethylnitrosamine (DMN) permanently enhanced, and the noncarcinogenic pulmonary toxicants paraquat (PAR) and butylated hydroxytoluene (BHT) temporarily, enhanced the activities of hexokinase (HK), phosphofructokinase (PFK), and pyruvate kinase (PK) in the lungs of mice.

  3. Roles of key active-site residues in flavocytochrome P450 BM3.

    PubMed Central

    Noble, M A; Miles, C S; Chapman, S K; Lysek, D A; MacKay, A C; Reid, G A; Hanzlik, R P; Munro, A W

    1999-01-01

    The effects of mutation of key active-site residues (Arg-47, Tyr-51, Phe-42 and Phe-87) in Bacillus megaterium flavocytochrome P450 BM3 were investigated. Kinetic studies on the oxidation of laurate and arachidonate showed that the side chain of Arg-47 contributes more significantly to stabilization of the fatty acid carboxylate than does that of Tyr-51 (kinetic parameters for oxidation of laurate: R47A mutant, Km 859 microM, kcat 3960 min-1; Y51F mutant, Km 432 microM, kcat 6140 min-1; wild-type, Km 288 microM, kcat 5140 min-1). A slightly increased kcat for the Y51F-catalysed oxidation of laurate is probably due to decreased activation energy (DeltaG) resulting from a smaller DeltaG of substrate binding. The side chain of Phe-42 acts as a phenyl 'cap' over the mouth of the substrate-binding channel. With mutant F42A, Km is massively increased and kcat is decreased for oxidation of both laurate (Km 2. 08 mM, kcat 2450 min-1) and arachidonate (Km 34.9 microM, kcat 14620 min-1; compared with values of 4.7 microM and 17100 min-1 respectively for wild-type). Amino acid Phe-87 is critical for efficient catalysis. Mutants F87G and F87Y not only exhibit increased Km and decreased kcat values for fatty acid oxidation, but also undergo an irreversible conversion process from a 'fast' to a 'slow' rate of substrate turnover [for F87G (F87Y)-catalysed laurate oxidation: kcat 'fast', 760 (1620) min-1; kcat 'slow', 48.0 (44.6) min-1; kconv (rate of conversion from fast to slow form), 4.9 (23.8) min-1]. All mutants showed less than 10% uncoupling of NADPH oxidation from fatty acid oxidation. The rate of FMN-to-haem electron transfer was shown to become rate-limiting in all mutants analysed. For wild-type P450 BM3, the rate of FMN-to-haem electron transfer (8340 min-1) is twice the steady-state rate of oxidation (4100 min-1), indicating that other steps contribute to rate limitation. Active-site structures of the mutants were probed with the inhibitors 12-(imidazolyl

  4. Biological activity in Technosols as a key factor of their structure

    NASA Astrophysics Data System (ADS)

    Watteau, Françoise; Villemin, Geneviève; Bouchard, Adeline; Monserié, Marie-France; Séré, Geoffroy; Schwartz, Christophe; Morel, Jean-Louis

    2010-05-01

    )availability. HAP also contributed to the aggregation of technogenic constituents in Technosol 1. The biological activity generated by the presence of exogenous organic matter is thus in short (0-2 years) and mean (30 years) terms, a key factor of the structuration and by there of the pedogenesis of Technosols.

  5. Distinguishing Target From Distractor in Stroop, Picture-Word, and Word-Word Interference Tasks.

    PubMed

    Schmalz, Xenia; Treccani, Barbara; Mulatti, Claudio

    2015-01-01

    Lexical selection-both during reading aloud and speech production-involves selecting an intended word, while ignoring irrelevant lexical activation. This process has been studied by the use of interference tasks. Examples are the Stroop task, where participants ignore the written color word and name the color of the ink, picture-word interference tasks, where participants name a picture while ignoring a super-imposed written word, or word-word interference (WWI) tasks, where two words are presented and the participants need to respond to only one, based on an pre-determined visual feature (e.g., color, position). Here, we focus on the WWI task: it is theoretically impossible for existing models to explain how the cognitive system can respond to one stimulus and block the other, when they are presented by the same modality (i.e., they are both words). We describe a solution that can explain performance on the WWI task: drawing on the literature on visual attention, we propose that the system creates an object file for each perceived object, which is continuously updated with increasingly complete information about the stimulus, such as the task-relevant visual feature. Such a model can account for performance on all three tasks.

  6. Neuromagnetic brain activities associated with perceptual categorization and sound-content incongruency: a comparison between monosyllabic words and pitch names

    PubMed Central

    Tsai, Chen-Gia; Chen, Chien-Chung; Wen, Ya-Chien; Chou, Tai-Li

    2015-01-01

    In human cultures, the perceptual categorization of musical pitches relies on pitch-naming systems. A sung pitch name concurrently holds the information of fundamental frequency and pitch name. These two aspects may be either congruent or incongruent with regard to pitch categorization. The present study aimed to compare the neuromagnetic responses to musical and verbal stimuli for congruency judgments, for example a congruent pair for the pitch C4 sung with the pitch name do in a C-major context (the pitch-semantic task) or for the meaning of a word to match the speaker’s identity (the voice-semantic task). Both the behavioral data and neuromagnetic data showed that congruency detection of the speaker’s identity and word meaning was slower than that of the pitch and pitch name. Congruency effects of musical stimuli revealed that pitch categorization and semantic processing of pitch information were associated with P2m and N400m, respectively. For verbal stimuli, P2m and N400m did not show any congruency effect. In both the pitch-semantic task and the voice-semantic task, we found that incongruent stimuli evoked stronger slow waves with the latency of 500–600 ms than congruent stimuli. These findings shed new light on the neural mechanisms underlying pitch-naming processes. PMID:26347638

  7. Implicit and Explicit Attention to Pictures and Words: An fMRI-Study of Concurrent Emotional Stimulus Processing.

    PubMed

    Flaisch, Tobias; Imhof, Martin; Schmälzle, Ralf; Wentz, Klaus-Ulrich; Ibach, Bernd; Schupp, Harald T

    2015-01-01

    The present study utilized functional magnetic resonance imaging (fMRI) to examine the neural processing of concurrently presented emotional stimuli under varying explicit and implicit attention demands. Specifically, in separate trials, participants indicated the category of either pictures or words. The words were placed over the center of the pictures and the picture-word compound-stimuli were presented for 1500 ms in a rapid event-related design. The results reveal pronounced main effects of task and emotion: the picture categorization task prompted strong activations in visual, parietal, temporal, frontal, and subcortical regions; the word categorization task evoked increased activation only in left extrastriate cortex. Furthermore, beyond replicating key findings regarding emotional picture and word processing, the results point to a dissociation of semantic-affective and sensory-perceptual processes for words: while emotional words engaged semantic-affective networks of the left hemisphere regardless of task, the increased activity in left extrastriate cortex associated with explicitly attending to words was diminished when the word was overlaid over an erotic image. Finally, we observed a significant interaction between Picture Category and Task within dorsal visual-associative regions, inferior parietal, and dorsolateral, and medial prefrontal cortices: during the word categorization task, activation was increased in these regions when the words were overlaid over erotic as compared to romantic pictures. During the picture categorization task, activity in these areas was relatively decreased when categorizing erotic as compared to romantic pictures. Thus, the emotional intensity of the pictures strongly affected brain regions devoted to the control of task-related word or picture processing. These findings are discussed with respect to the interplay of obligatory stimulus processing with task-related attentional control mechanisms.

  8. Implicit and Explicit Attention to Pictures and Words: An fMRI-Study of Concurrent Emotional Stimulus Processing

    PubMed Central

    Flaisch, Tobias; Imhof, Martin; Schmälzle, Ralf; Wentz, Klaus-Ulrich; Ibach, Bernd; Schupp, Harald T.

    2015-01-01

    The present study utilized functional magnetic resonance imaging (fMRI) to examine the neural processing of concurrently presented emotional stimuli under varying explicit and implicit attention demands. Specifically, in separate trials, participants indicated the category of either pictures or words. The words were placed over the center of the pictures and the picture-word compound-stimuli were presented for 1500 ms in a rapid event-related design. The results reveal pronounced main effects of task and emotion: the picture categorization task prompted strong activations in visual, parietal, temporal, frontal, and subcortical regions; the word categorization task evoked increased activation only in left extrastriate cortex. Furthermore, beyond replicating key findings regarding emotional picture and word processing, the results point to a dissociation of semantic-affective and sensory-perceptual processes for words: while emotional words engaged semantic-affective networks of the left hemisphere regardless of task, the increased activity in left extrastriate cortex associated with explicitly attending to words was diminished when the word was overlaid over an erotic image. Finally, we observed a significant interaction between Picture Category and Task within dorsal visual-associative regions, inferior parietal, and dorsolateral, and medial prefrontal cortices: during the word categorization task, activation was increased in these regions when the words were overlaid over erotic as compared to romantic pictures. During the picture categorization task, activity in these areas was relatively decreased when categorizing erotic as compared to romantic pictures. Thus, the emotional intensity of the pictures strongly affected brain regions devoted to the control of task-related word or picture processing. These findings are discussed with respect to the interplay of obligatory stimulus processing with task-related attentional control mechanisms. PMID:26733895

  9. Jasper Johns' Painted Words.

    ERIC Educational Resources Information Center

    Levinger, Esther

    1989-01-01

    States that the painted words in Jasper Johns' art act in two different capacities: concealed words partake in the artist's interrogation of visual perception; and visible painted words question classical representation. Argues that words are Johns' means of critiquing modernism. (RS)

  10. Direct transcriptional activation of BT genes by NLP transcription factors is a key component of the nitrate response in Arabidopsis.

    PubMed

    Sato, Takeo; Maekawa, Shugo; Konishi, Mineko; Yoshioka, Nozomi; Sasaki, Yuki; Maeda, Haruna; Ishida, Tetsuya; Kato, Yuki; Yamaguchi, Junji; Yanagisawa, Shuichi

    2017-01-29

    Nitrate modulates growth and development, functioning as a nutrient signal in plants. Although many changes in physiological processes in response to nitrate have been well characterized as nitrate responses, the molecular mechanisms underlying the nitrate response are not yet fully understood. Here, we show that NLP transcription factors, which are key regulators of the nitrate response, directly activate the nitrate-inducible expression of BT1 and BT2 encoding putative scaffold proteins with a plant-specific domain structure in Arabidopsis. Interestingly, the 35S promoter-driven expression of BT2 partially rescued growth inhibition caused by reductions in NLP activity in Arabidopsis. Furthermore, simultaneous disruption of BT1 and BT2 affected nitrate-dependent lateral root development. These results suggest that direct activation of BT1 and BT2 by NLP transcriptional activators is a key component of the molecular mechanism underlying the nitrate response in Arabidopsis.

  11. A Few Words about Words | Poster

    Cancer.gov

    By Ken Michaels, Guest Writer In Shakepeare’s play “Hamlet,” Polonius inquires of the prince, “What do you read, my lord?” Not at all pleased with what he’s reading, Hamlet replies, “Words, words, words.”1 I have previously described the communication model in which a sender encodes a message and then sends it via some channel (or medium) to a receiver, who decodes the message and, ideally, understands what was sent. Surely the most common way of encoding a message is in choosing the most appropriate words for the listener or reader.

  12. Computational Method for the Systematic Identification of Analog Series and Key Compounds Representing Series and Their Biological Activity Profiles.

    PubMed

    Stumpfe, Dagmar; Dimova, Dilyana; Bajorath, Jürgen

    2016-08-25

    A computational methodology is introduced for detecting all unique series of analogs in large compound data sets, regardless of chemical relationships between analogs. No prior knowledge of core structures or R-groups is required, which are automatically determined. The approach is based upon the generation of retrosynthetic matched molecular pairs and analog networks from which distinct series are isolated. The methodology was applied to systematically extract more than 17 000 distinct series from the ChEMBL database. For comparison, analog series were also isolated from screening compounds and drugs. Known biological activities were mapped to series from ChEMBL, and in more than 13 000 of these series, key compounds were identified that represented substitution sites of all analogs within a series and its complete activity profile. The analog series, key compounds, and activity profiles are made freely available as a resource for medicinal chemistry applications.

  13. Muscle RANK is a key regulator of Ca2+ storage, SERCA activity, and function of fast-twitch skeletal muscles.

    PubMed

    Dufresne, Sébastien S; Dumont, Nicolas A; Boulanger-Piette, Antoine; Fajardo, Val A; Gamu, Daniel; Kake-Guena, Sandrine-Aurélie; David, Rares Ovidiu; Bouchard, Patrice; Lavergne, Éliane; Penninger, Josef M; Pape, Paul C; Tupling, A Russell; Frenette, Jérôme

    2016-04-15

    Receptor-activator of nuclear factor-κB (RANK), its ligand RANKL, and the soluble decoy receptor osteoprotegerin are the key regulators of osteoclast differentiation and bone remodeling. Here we show that RANK is also expressed in fully differentiated myotubes and skeletal muscle. Muscle RANK deletion has inotropic effects in denervated, but not in sham, extensor digitorum longus (EDL) muscles preventing the loss of maximum specific force while promoting muscle atrophy, fatigability, and increased proportion of fast-twitch fibers. In denervated EDL muscles, RANK deletion markedly increased stromal interaction molecule 1 content, a Ca(2+)sensor, and altered activity of the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) modulating Ca(2+)storage. Muscle RANK deletion had no significant effects on the sham or denervated slow-twitch soleus muscles. These data identify a novel role for RANK as a key regulator of Ca(2+)storage and SERCA activity, ultimately affecting denervated skeletal muscle function.

  14. Immediate lexical integration of novel word forms.

    PubMed

    Kapnoula, Efthymia C; Packard, Stephanie; Gupta, Prahlad; McMurray, Bob

    2015-01-01

    It is well known that familiar words inhibit each other during spoken word recognition. However, we do not know how and under what circumstances newly learned words become integrated with the lexicon in order to engage in this competition. Previous work on word learning has highlighted the importance of offline consolidation (Gaskell & Dumay, 2003) and meaning (Leach & Samuel, 2007) to establish this integration. In two experiments we test the necessity of these factors by examining the inhibition between newly learned items and familiar words immediately after learning. Participants learned a set of nonwords without meanings in active (Experiment 1) or passive (Experiment 2) exposure paradigms. After training, participants performed a visual world paradigm task to assess inhibition from these newly learned items. An analysis of participants' fixations suggested that the newly learned words were able to engage in competition with known words without any consolidation.

  15. Microcomputers: Word Processing. Evaluation Guides. Guide Number 3.

    ERIC Educational Resources Information Center

    Gray, Peter J.

    Designed to provide guidance in selecting the appropriate microcomputer-based word processing program, this document discusses the key characteristics of word processing software, including formatting, editing, merging, and printing. Possible capabilities of word processing features are identified, i.e., indent, tab, center, creation of footnotes,…

  16. Physical Activity in Child-Care Centers: Do Teachers Hold the Key to the Playground?

    ERIC Educational Resources Information Center

    Copeland, Kristen A.; Kendeigh, Cassandra A.; Saelens, Brian E.; Kalkwarf, Heidi J.; Sherman, Susan N.

    2012-01-01

    Many (56%) US children aged 3-5 years are in center-based childcare and are not obtaining recommended levels of physical activity. In order to determine what child-care teachers/providers perceived as benefits and barriers to children's physical activity in child-care centers, we conducted nine focus groups and 13 one-on-one interviews with 49…

  17. Visual cortex activation in late-onset, Braille naive blind individuals: an fMRI study during semantic and phonological tasks with heard words.

    PubMed

    Burton, Harold; McLaren, Donald G

    2006-01-09

    Visual cortex activity in the blind has been shown in Braille literate people, which raise the question of whether Braille literacy influences cross-modal reorganization. We used fMRI to examine visual cortex activation during semantic and phonological tasks with auditory presentation of words in two late-onset blind individuals who lacked Braille literacy. Multiple visual cortical regions were activated in the Braille naive individuals. Positive BOLD responses were noted in lower tier visuotopic (e.g., V1, V2, VP, and V3) and several higher tier visual areas (e.g., V4v, V8, and BA 37). Activity was more extensive and cross-correlation magnitudes were greater during the semantic compared to the phonological task. These results with Braille naive individuals plausibly suggest that visual deprivation alone induces visual cortex reorganization. Cross-modal reorganization of lower tier visual areas may be recruited by developing skills in attending to selected non-visual inputs (e.g., Braille literacy, enhanced auditory skills). Such learning might strengthen remote connections with multisensory cortical areas. Of necessity, the Braille naive participants must attend to auditory stimulation for language. We hypothesize that learning to attend to non-visual inputs probably strengthens the remaining active synapses following visual deprivation, and thereby, increases cross-modal activation of lower tier visual areas when performing highly demanding non-visual tasks of which reading Braille is just one example.

  18. Getting the "Words" In

    ERIC Educational Resources Information Center

    Bolinger, Dwight

    1970-01-01

    Suggests that grammar is not something into which words are plugged but is rather a mechanism by which words are served and that linguistics scientists must begin to devote a major part of their attention to lexicology. (TO)

  19. Toll-like receptors: key activators of leucocytes and regulator of haematopoiesis.

    PubMed

    McGettrick, Anne F; O'Neill, Luke A J

    2007-10-01

    Toll-like receptors (TLRs) play a critical role in the induction of the immune response to invading pathogens. The detection of pathogens by TLRs initiates a signalling cascade that results in the activation of transcription factors such as nuclear factor (NF)-kappaB and interferon regulatory factors leading to the production of pro-inflammatory cytokines and type 1 interferons. Five cytoplasmic adaptors, MyD88, Mal, Trif, TRAM and SARM, are utilized by the TLRs to activate these signalling pathways. Through the years the main focus of research has been on the activation and function of TLRs in monocytic cells. This review discusses several additional roles of TLRs. TLR activation plays a role in influencing the differentiation of haematopoietic stem cells. Their activation also prevents apoptosis in neutrophils following pathogen invasion. B cells and T cells proliferation and differentiation is influenced by TLR activation and the possible therapeutic benefits of using TLR ligands for the treatment of chronic lymphocytic leukaemia will also be discussed.

  20. Mechanisms of Word Identification

    ERIC Educational Resources Information Center

    Mewhort, D. J. K.; Beal, A. Lynne

    1977-01-01

    Three word-identification experiments suggest that a model derived from experiments with pseudowords can be applied successfully to word identification. The data derived from the experiments confirm the role of higher order verbal units in word identification and suggest the structural components of a verbal-mediation theory of reading. (Editor/RK)

  1. Units of Word Recognition.

    ERIC Educational Resources Information Center

    Santa, Carol M.; And Others

    Both psychologists and reading specialists have been interested in whether words are processed letter by letter or in larger units. A reaction time paradigm was used to evaluate these options with interest focused on potential units of word recognition which might be functional within single syllable words. The basic paradigm involved presenting…

  2. In a Word, History

    ERIC Educational Resources Information Center

    Dohan, Mary Helen

    1977-01-01

    Understanding words like "bionics" will open the mind to the horizons of another time when words like "railroad" evoked wonder and "to fly to the moon" was a metaphor for the impossible dream. Suggests that history teachers and English teachers should join together in using words to teach both subjects. (Editor/RK)

  3. Words in Science.

    ERIC Educational Resources Information Center

    Gardner, Paul L.

    This is a report of a project designed to identify important non-technical words used in the teaching of science at Form 3 and 4 level in the Territory of Papua and New Guinea (T.P.N.G.). After the words were identified, multiple choice items testing the comprehension of these words were written, tried out and revised. Fifteen final tests, each…

  4. Interactive Word Walls

    ERIC Educational Resources Information Center

    Jackson, Julie; Narvaez, Rose

    2013-01-01

    It is common to see word walls displaying the vocabulary that students have learned in class. Word walls serve as visual scaffolds and are a classroom strategy used to reinforce reading and language arts instruction. Research shows a strong relationship between student word knowledge and academic achievement (Stahl and Fairbanks 1986). As a…

  5. Key mediators of intracellular amino acids signaling to mTORC1 activation.

    PubMed

    Duan, Yehui; Li, Fengna; Tan, Kunrong; Liu, Hongnan; Li, Yinghui; Liu, Yingying; Kong, Xiangfeng; Tang, Yulong; Wu, Guoyao; Yin, Yulong

    2015-05-01

    Mammalian target of rapamycin complex 1 (mTORC1) is activated by amino acids to promote cell growth via protein synthesis. Specifically, Ras-related guanosine triphosphatases (Rag GTPases) are activated by amino acids, and then translocate mTORC1 to the surface of late endosomes and lysosomes. Ras homolog enriched in brain (Rheb) resides on this surface and directly activates mTORC1. Apart from the presence of intracellular amino acids, Rag GTPases and Rheb, other mediators involved in intracellular amino acid signaling to mTORC1 activation include human vacuolar sorting protein-34 (hVps34) and mitogen-activating protein kinase kinase kinase kinase-3 (MAP4K3). Those molecular links between mTORC1 and its mediators form a complicate signaling network that controls cellular growth, proliferation, and metabolism. Moreover, it is speculated that amino acid signaling to mTORC1 may start from the lysosomal lumen. In this review, we discussed the function of these mediators in mTORC1 pathway and how these mediators are regulated by amino acids in details.

  6. Prediction of Geomagnetic Activity and Key Parameters in High-latitude Ionosphere

    NASA Technical Reports Server (NTRS)

    Khazanov, George V.; Lyatsky, Wladislaw; Tan, Arjun; Ridley, Aaron

    2007-01-01

    Prediction of geomagnetic activity and related events in the Earth's magnetosphere and ionosphere are important tasks of US Space Weather Program. Prediction reliability is dependent on the prediction method, and elements included in the prediction scheme. Two of the main elements of such prediction scheme are: an appropriate geomagnetic activity index, and an appropriate coupling function (the combination of solar wind parameters providing the best correlation between upstream solar wind data and geomagnetic activity). We have developed a new index of geomagnetic activity, the Polar Magnetic (PM) index and an improved version of solar wind coupling function. PM index is similar to the existing polar cap PC index but it shows much better correlation with upstream solar wind/IMF data and other events in the magnetosphere and ionosphere. We investigate the correlation of PM index with upstream solar wind/IMF data for 10 years (1995-2004) that include both low and high solar activity. We also have introduced a new prediction function for the predicting of cross-polar-cap voltage and Joule heating based on using both PM index and upstream solar wind/IMF data. As we show such prediction function significantly increase the reliability of prediction of these important parameters. The correlation coefficients between the actual and predicted values of these parameters are approx. 0.9 and higher.

  7. Niche as a Determinant of Word Fate in Online Groups

    PubMed Central

    Altmann, Eduardo G.; Pierrehumbert, Janet B.; Motter, Adilson E.

    2011-01-01

    Patterns of word use both reflect and influence a myriad of human activities and interactions. Like other entities that are reproduced and evolve, words rise or decline depending upon a complex interplay between their intrinsic properties and the environments in which they function. Using Internet discussion communities as model systems, we define the concept of a word niche as the relationship between the word and the characteristic features of the environments in which it is used. We develop a method to quantify two important aspects of the size of the word niche: the range of individuals using the word and the range of topics it is used to discuss. Controlling for word frequency, we show that these aspects of the word niche are strong determinants of changes in word frequency. Previous studies have already indicated that word frequency itself is a correlate of word success at historical time scales. Our analysis of changes in word frequencies over time reveals that the relative sizes of word niches are far more important than word frequencies in the dynamics of the entire vocabulary at shorter time scales, as the language adapts to new concepts and social groupings. We also distinguish endogenous versus exogenous factors as additional contributors to the fates of words, and demonstrate the force of this distinction in the rise of novel words. Our results indicate that short-term nonstationarity in word statistics is strongly driven by individual proclivities, including inclinations to provide novel information and to project a distinctive social identity. PMID:21589910

  8. Florida Keys

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Florida Keys are a chain of islands, islets and reefs extending from Virginia Key to the Dry Tortugas for about 309 kilometers (192 miles). The keys are chiefly limestone and coral formations. The larger islands of the group are Key West (with its airport), Key Largo, Sugarloaf Key, and Boca Chica Key. A causeway extends from the mainland to Key West.

    This image was acquired on October 28, 2001, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long- term research effort to understand and protect our home planet. Through the study of Earth, NASA will help to provide sound science to policy and economic

  9. Behavioral science in video games for children's diet and physical activity change: Key research needs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Innovative intervention programs are needed to overcome the limitations in previous programs that promoted change in diabetes risk behaviors in children. Serious video games show promise of changing dietary and physical activity behaviors, but research is needed on the optimal design of behavior-cha...

  10. Enjoyment Fosters Engagement: The Key to Involving Middle School Students in Physical Education and Physical Activity

    ERIC Educational Resources Information Center

    Pharez, Emily S.

    2016-01-01

    This article describes the challenges faced by a middle school teacher who inherited a recreation-based physical education program in which students had been accustomed to choosing what they wanted to do. Stressing the importance of implementing a standards-based program in which students of all skill levels and activity preferences were able to…

  11. Collaboration with aviation — The key to commercialisation of space activities

    NASA Astrophysics Data System (ADS)

    Collins, Patrick; Funatsu, Yoshiyuki

    2000-07-01

    The US government's Commercial Space Act of 1998 and commitment to commercialise the International Space Station's operations have changed the direction of space development in the post-cold-war world definitively. During 1998 also the feasibility and great economic potential of space travel by the general public was acknowledged in publications by NASA, AIAA and the Japanese Keidanren. However, crewed space activities are all taxpayer-funded, primarily for scientific research; they have involved only a few hundred people traveling to space to date; and those involved have no experience of commercial passenger service operations. By contrast, aviation is a global industry, largely commercial, involving the range of activities from engineering design to marketing, and serving more than 1 billion passengers/year. Aviation has very high safety levels developed over decades of experience of carrying billions of passengers. Furthermore, the aviation industry also has extensive experience of operating rocket-powered piloted vehicles: during the 1950s several countries operated such vehicles sufficiently frequently to develop routine operations, maintenance and repair procedures. Consequently, in order to develop safe and profitable passenger travel services to, from and in space, people, companies and organisations with experience of space activities have a great deal to gain from collaboration with all parts of the aviation industry. Due to the potential economic value of this development, and the high cost to taxpayers of space activities today, governments should take steps to start this collaboration as soon as possible.

  12. Physical activity in child-care centers: do teachers hold the key to the playground?

    PubMed Central

    Copeland, Kristen A.; Kendeigh, Cassandra A.; Saelens, Brian E.; Kalkwarf, Heidi J.; Sherman, Susan N.

    2012-01-01

    Many (56%) US children aged 3–5 years are in center-based childcare and are not obtaining recommended levels of physical activity. In order to determine what child-care teachers/providers perceived as benefits and barriers to children’s physical activity in child-care centers, we conducted nine focus groups and 13 one-on-one interviews with 49 child-care teachers/providers in Cincinnati, OH. Participants noted physical and socio-emotional benefits of physical activity particular to preschoolers (e.g. gross motor skill development, self-confidence after mastery of new skills and improved mood, attention and napping after exercise) but also noted several barriers including their own personal attitudes (e.g. low self-efficacy) and preferences to avoid the outdoors (e.g. don’t like hot/cold weather, getting dirty, chaos of playground). Because individual teachers determine daily schedules and ultimately make the decision whether to take the children outdoors, they serve as gatekeepers to the playground. Participants discussed a spectrum of roles on the playground, from facilitator to chaperone to physical activity inhibitor. These findings suggest that children could have very different gross motor experiences even within the same facility (with presumably the same environment and policies), based on the beliefs, creativity and level of engagement of their teacher. PMID:21804083

  13. Increasing AIP Macrocycle Size Reveals Key Features of agr Activation in Staphylococcus aureus.

    PubMed

    Johnson, Jeffrey G; Wang, Boyuan; Debelouchina, Galia T; Novick, Richard P; Muir, Tom W

    2015-05-04

    The agr locus in the commensal human pathogen, Staphylococcus aureus, is a two-promoter regulon with allelic variability that produces a quorum-sensing circuit involved in regulating virulence within the bacterium. Secretion of unique autoinducing peptides (AIPs) and detection of their concentrations by AgrC, a transmembrane receptor histidine kinase, coordinates local bacterial population density with global changes in gene expression. The finding that staphylococcal virulence can be inhibited through antagonism of this quorum-sensing pathway has fueled tremendous interest in understanding the structure-activity relationships underlying the AIP-AgrC interaction. The defining structural feature of the AIP is a 16-membered, thiolactone-containing macrocycle. Surprisingly, the importance of ring size on agr activation or inhibition has not been explored. In this study, we address this deficiency through the synthesis and functional analysis of AIP analogues featuring enlarged and reduced macrocycles. Notably, this study is the first to interrogate AIP function by using both established cell-based reporter gene assays and newly developed in vitro AgrC-I binding and autophosphorylation activity assays. Based on our data, we present a model for robust agr activation involving a cooperative, three-points-of-contact interaction between the AIP macrocycle and AgrC.

  14. Making Physics Fun: Key Concepts, Classroom Activities, and Everyday Examples, Grades K-8

    ERIC Educational Resources Information Center

    Prigo, Robert

    2007-01-01

    Teaching physical science in the elementary and middle grades can be challenging for busy teachers faced with growing science demands and limited classroom resources. Robert Prigo provides fun and engaging activities using safe, available materials that educators can easily incorporate into lesson plans. Extensive examples, sample inquiry…

  15. The Key Factors of an Active Learning Method in a Microprocessors Course

    ERIC Educational Resources Information Center

    Carpeno, A.; Arriaga, J.; Corredor, J.; Hernandez, J.

    2011-01-01

    The creation of the European Higher Education Area (EHEA) is promoting a change toward a new model of education focused on the student. It is impelling methodological innovation processes in many European universities, leading more teachers to apply methods based on active and cooperative learning in their classrooms. However, the successful…

  16. Key programmatic steps and activities for implementing the Uranium Mill Tailings Remedial Action Project. [UMTRA Project

    SciTech Connect

    Not Available

    1985-07-01

    The Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA) was enacted based upon findings by Congress that uranium mill tailings located at active and inactive hazard to the public, and that protection of the public health, safety and welfare, and the regulations of interstate commerce, require that every reasonable effort be made to provide for the stabilization, disposal, and control in a safe and environmentally sound manner of such tailings in order to prevent or minimize radon diffusion into the environment and to prevent or minimize other environmental hazards from such tailings.'' A general understanding of the steps leading to elimination of the hazards associated with designated uranium mill tailings sites, and the parties involved in that effort, are presented in this document. A representative schedule is also presented in this document to show both program sequence and activity interdependence. Those activities that have the most potential to influence program duration, because of the significant amount of additional time that may be required, include identification and selection of a suitable site, field data collection delays due to weather, actual acquisition of the designated or alternate disposal site, construction delays due to weather, and site licensing. This document provides an understanding of the steps, the sequence, the parties involved, and a representative duration of activities leading to remedial action and cleanup at the designated inactive uranium mill tailings sites. 10 refs., 5 figs., 1 tab.

  17. Identifying key areas for active interprofessional learning partnerships: A facilitated dialogue.

    PubMed

    Steven, Kathryn; Angus, Allyson; Breckenridge, Jenna; Davey, Peter; Tully, Vicki; Muir, Fiona

    2016-11-01

    Student and service user involvement is recognised as an important factor in creating interprofessional education (IPE) opportunities. We used a team-based learning approach to bring together undergraduate health professional students, early career professionals (ECPs), public partners, volunteers, and carers to explore learning partnerships. Influenced by evaluative inquiry, this qualitative study used a free text response to allow participants to give their own opinion. A total of 153 participants (50 public partners and 103 students and professionals representing 11 healthcare professions) took part. Participants were divided into mixed groups of six (n = 25) and asked to identify areas where students, professionals, and public could work together to improve health professional education. Each group documented their discussions by summarising agreed areas and next steps. Responses were collected and transcribed for inductive content analysis. Seven key themes (areas for joint working) were identified: communication, public as partners, standards of conduct, IPE, quality improvement, education, and learning environments. The team-based learning format enabled undergraduate and postgraduate health professionals to achieve consensus with public partners on areas for IPE and collaboration. Some of our results may be context-specific but the approach is generalisable to other areas.

  18. Activated macrophages as key mediators of capsule formation on adipose constructs in tissue engineering chamber models.

    PubMed

    Zhan, Weiqing; Lu, Feng

    2017-04-01

    In plastic and reconstructive field, it would be much beneficial to fabricate an engineered adipose tissue substitute allowing reliable and complete fat tissue regeneration. Tissue engineering chamber (TEC) holds the promise to optimize an adipogenic configuration that is efficacious as well as reproducible. A frequently occurring complication involves the adipose tissue flap encapsulation and, effectively, its shielding, by a thick fibrous membrane, which hinders development into the proliferative stage. The reason for the deposition of the collagen capsule remains unclear. Numerous studies have highlighted that macrophages play a key role in adipogenesis in a TEC model using a silicone chamber enclosing the fat flap with a superficial epigastric pedicle. As a verification of the role of macrophages in capsule formation, we propose the inhibition of transforming growth factor β1 (TGF-β1) synthesis by macrophage populations in the local microenvironment by administrating tranilast into the TEC. We hypothesize that upon reduction of TGF-β1 levels, capsule formation and inhibition of new adipose tissue development will decrease. Furthermore, we propose that a tissue engineering chamber model in which macrophages are closely related to both neo-adipogenesis and capsule formation.

  19. Active chromatin and transcription play a key role in chromosome partitioning into topologically associating domains

    PubMed Central

    Ulianov, Sergey V.; Khrameeva, Ekaterina E.; Gavrilov, Alexey A.; Flyamer, Ilya M.; Kos, Pavel; Mikhaleva, Elena A.; Penin, Aleksey A.; Logacheva, Maria D.; Imakaev, Maxim V.; Chertovich, Alexander; Gelfand, Mikhail S.; Shevelyov, Yuri Y.; Razin, Sergey V.

    2016-01-01

    Recent advances enabled by the Hi-C technique have unraveled many principles of chromosomal folding that were subsequently linked to disease and gene regulation. In particular, Hi-C revealed that chromosomes of animals are organized into topologically associating domains (TADs), evolutionary conserved compact chromatin domains that influence gene expression. Mechanisms that underlie partitioning of the genome into TADs remain poorly understood. To explore principles of TAD folding in Drosophila melanogaster, we performed Hi-C and poly(A)+ RNA-seq in four cell lines of various origins (S2, Kc167, DmBG3-c2, and OSC). Contrary to previous studies, we find that regions between TADs (i.e., the inter-TADs and TAD boundaries) in Drosophila are only weakly enriched with the insulator protein dCTCF, while another insulator protein Su(Hw) is preferentially present within TADs. However, Drosophila inter-TADs harbor active chromatin and constitutively transcribed (housekeeping) genes. Accordingly, we find that binding of insulator proteins dCTCF and Su(Hw) predicts TAD boundaries much worse than active chromatin marks do. Interestingly, inter-TADs correspond to decompacted inter-bands of polytene chromosomes, whereas TADs mostly correspond to densely packed bands. Collectively, our results suggest that TADs are condensed chromatin domains depleted in active chromatin marks, separated by regions of active chromatin. We propose the mechanism of TAD self-assembly based on the ability of nucleosomes from inactive chromatin to aggregate, and lack of this ability in acetylated nucleosomal arrays. Finally, we test this hypothesis by polymer simulations and find that TAD partitioning may be explained by different modes of inter-nucleosomal interactions for active and inactive chromatin. PMID:26518482

  20. Active chromatin and transcription play a key role in chromosome partitioning into topologically associating domains.

    PubMed

    Ulianov, Sergey V; Khrameeva, Ekaterina E; Gavrilov, Alexey A; Flyamer, Ilya M; Kos, Pavel; Mikhaleva, Elena A; Penin, Aleksey A; Logacheva, Maria D; Imakaev, Maxim V; Chertovich, Alexander; Gelfand, Mikhail S; Shevelyov, Yuri Y; Razin, Sergey V

    2016-01-01

    Recent advances enabled by the Hi-C technique have unraveled many principles of chromosomal folding that were subsequently linked to disease and gene regulation. In particular, Hi-C revealed that chromosomes of animals are organized into topologically associating domains (TADs), evolutionary conserved compact chromatin domains that influence gene expression. Mechanisms that underlie partitioning of the genome into TADs remain poorly understood. To explore principles of TAD folding in Drosophila melanogaster, we performed Hi-C and poly(A)(+) RNA-seq in four cell lines of various origins (S2, Kc167, DmBG3-c2, and OSC). Contrary to previous studies, we find that regions between TADs (i.e., the inter-TADs and TAD boundaries) in Drosophila are only weakly enriched with the insulator protein dCTCF, while another insulator protein Su(Hw) is preferentially present within TADs. However, Drosophila inter-TADs harbor active chromatin and constitutively transcribed (housekeeping) genes. Accordingly, we find that binding of insulator proteins dCTCF and Su(Hw) predicts TAD boundaries much worse than active chromatin marks do. Interestingly, inter-TADs correspond to decompacted inter-bands of polytene chromosomes, whereas TADs mostly correspond to densely packed bands. Collectively, our results suggest that TADs are condensed chromatin domains depleted in active chromatin marks, separated by regions of active chromatin. We propose the mechanism of TAD self-assembly based on the ability of nucleosomes from inactive chromatin to aggregate, and lack of this ability in acetylated nucleosomal arrays. Finally, we test this hypothesis by polymer simulations and find that TAD partitioning may be explained by different modes of inter-nucleosomal interactions for active and inactive chromatin.

  1. The time of day differently influences fatigue and locomotor activity: is body temperature a key factor?

    PubMed

    Machado, Frederico Sander Mansur; Rodovalho, Gisele Vieira; Coimbra, Cândido Celso

    2015-03-01

    The aim of this study was to verify the possible interactions between exercise capacity and spontaneous locomotor activity (SLA) during the oscillation of core body temperature (Tb) that occurs during the light/dark cycle. Wistar rats (n=11) were kept at an animal facility under a light/dark cycle of 14/10h at an ambient temperature of 23°C and water and food ad libitum. Initially, in order to characterize the daily oscillation in SLA and Tb of the rats, these parameters were continuously recorded for 24h using an implantable telemetric sensor (G2 E-Mitter). The animals were randomly assigned to two progressive exercise test protocols until fatigue during the beginning of light and dark-phases. Fatigue was defined as the moment rats could not keep pace with the treadmill. We assessed the time to fatigue, workload and Tb changes induced by exercise. Each test was separated by 3days. Our results showed that exercise capacity and heat storage were higher during the light-phase (p<0.05). In contrast, we observed that both SLA and Tb were higher during the dark-phase (p<0.01). Notably, the correlation analysis between the amount of SLA and the running capacity observed at each phase of the daily cycle revealed that, regardless of the time of the day, both types of locomotor physical activity have an important inherent component (r=0.864 and r=0.784, respectively, p<0.01) without a direct relationship between them. This finding provides further support for the existence of specific control mechanisms for each type of physical activity. In conclusion, our data indicate that the relationship between the body temperature and different types of physical activity might be affected by the light/dark cycle. These results mean that, although exercise performance and spontaneous locomotor activity are not directly associated, both are strongly influenced by daily cycles of light and dark.

  2. Phonological processing dynamics in bilingual word naming.

    PubMed

    Friesen, Deanna C; Jared, Debra; Haigh, Corinne A

    2014-09-01

    The current study investigated phonological processing dynamics in bilingual word naming. English-French and French-English bilinguals named interlingual heterophonic homographs (i.e., words that share orthography but not meaning or pronunciation across languages), heterophonic cognates (i.e., words that share both orthography and meaning across languages, but not pronunciations), interlingual homophones (i.e., words that share pronunciation, but not orthography or meaning across languages), and single-language matched control words in both English and French naming tasks. Cross-language phonological activation was strongest in bilinguals' second language. The results provided evidence for feedforward activation of phonological representations in the nontarget language, as well as feedback activation of these phonological representations from semantic representations. Results are interpreted within the more recent Bilingual Interactive Activation (BIA+) framework.

  3. S100A8/A9 activate key genes and pathways in colon tumor progression.

    PubMed

    Ichikawa, Mie; Williams, Roy; Wang, Ling; Vogl, Thomas; Srikrishna, Geetha

    2011-02-01

    The tumor microenvironment plays an important role in modulating tumor progression. Earlier, we showed that S100A8/A9 proteins secreted by myeloid-derived suppressor cells (MDSC) present within tumors and metastatic sites promote an autocrine pathway for accumulation of MDSC. In a mouse model of colitis-associated colon cancer, we also showed that S100A8/A9-positive cells accumulate in all regions of dysplasia and adenoma. Here we present evidence that S100A8/A9 interact with RAGE and carboxylated glycans on colon tumor cells and promote activation of MAPK and NF-κB signaling pathways. Comparison of gene expression profiles of S100A8/A9-activated colon tumor cells versus unactivated cells led us to identify a small cohort of genes upregulated in activated cells, including Cxcl1, Ccl5 and Ccl7, Slc39a10, Lcn2, Zc3h12a, Enpp2, and other genes, whose products promote leukocyte recruitment, angiogenesis, tumor migration, wound healing, and formation of premetastatic niches in distal metastatic organs. Consistent with this observation, in murine colon tumor models we found that chemokines were upregulated in tumors, and elevated in sera of tumor-bearing wild-type mice. Mice lacking S100A9 showed significantly reduced tumor incidence, growth and metastasis, reduced chemokine levels, and reduced infiltration of CD11b(+)Gr1(+) cells within tumors and premetastatic organs. Studies using bone marrow chimeric mice revealed that S100A8/A9 expression on myeloid cells is essential for development of colon tumors. Our results thus reveal a novel role for myeloid-derived S100A8/A9 in activating specific downstream genes associated with tumorigenesis and in promoting tumor growth and metastasis.

  4. Lipophilicity is a key factor to increase the antiviral activity of HIV neutralizing antibodies.

    PubMed

    Augusto, Marcelo T; Hollmann, Axel; Troise, Fulvia; Veiga, Ana S; Pessi, Antonello; Santos, Nuno C

    2017-04-01

    The HIV broadly neutralizing antibody 2F5 targets the transiently exposed epitope in the membrane proximal external region (MPER) of HIV-1 gp41, by a two-step mechanism involving the viral membrane and this viral glycoprotein. It was recently shown that 2F5 conjugation with a cholesterol moiety outside of the antibody paratope substantially increases its antiviral activity. Additionally, the antiviral activity of D5, a human antibody that binds to the N-terminal heptad repeat (NHR) of gp41 and lacks membrane binding, was boosted by the same cholesterol conjugation. In this work, we evaluated the membrane affinity of both antibodies towards membranes of different compositions, using surface plasmon resonance. A correlation was found between membrane affinity and antiviral activity against HIV-1. We propose that the conjugation of cholesterol to 2F5 or D5 allows a higher degree of antibody pre-concentration at the viral membrane. This way, the antibodies become more available to bind efficiently to the gp41 epitope, blocking viral fusion faster than the unconjugated antibody. These results set up a relevant strategy to improve the rational design of therapeutic antibodies against HIV.

  5. PIASxbeta is a key regulator of osterix transcriptional activity and matrix mineralization in osteoblasts.

    PubMed

    Ali, Md Moksed; Yoshizawa, Tatsuya; Ishibashi, Osamu; Matsuda, Akio; Ikegame, Mika; Shimomura, Junko; Mera, Hisashi; Nakashima, Kazuhisa; Kawashima, Hiroyuki

    2007-08-01

    We recently reported that tensile stress induces osteoblast differentiation and osteogenesis in the mouse calvarial suture in vitro. Using this experimental system, we identified PIASxbeta, a splice isoform of Pias2, as one of the genes most highly upregulated by tensile stress. Further study using cell culture revealed that this upregulation was transient and was accompanied by upregulation of other differentiation markers, including osterix, whereas expression of Runx2 was unaffected. Runx2 and osterix are the two master proteins controlling osteoblast differentiation, with Runx2 being upstream of osterix. Targeted knockdown of PIASxbeta by small interfering RNA (siRNA) markedly suppressed osteoblastic differentiation and matrix mineralization, whereas transient overexpression of PIASxbeta caused the exact opposite effects. Regardless of PIASxbeta expression level, Runx2 expression remained constant. Reporter assays demonstrated that osterix enhanced its own promoter activity, which was further stimulated by PIASxbeta but not by its sumoylation-defective mutant. NFATc1 and NFATc3 additionally increased osterix transcriptional activity when co-transfected with PIASxbeta. Because osterix has no consensus motif for sumoylation, other proteins are probably involved in the PIASxbeta-mediated activation and NFAT proteins may be among such targets. This study provides the first line of evidence that PIASxbeta is indispensable for osteoblast differentiation and matrix mineralization, and that this signaling molecule is located between Runx2 and osterix.

  6. Lactic acid bacterial symbionts in honeybees - an unknown key to honey's antimicrobial and therapeutic activities.

    PubMed

    Olofsson, Tobias C; Butler, Èile; Markowicz, Pawel; Lindholm, Christina; Larsson, Lennart; Vásquez, Alejandra

    2016-10-01

    Could honeybees' most valuable contribution to mankind besides pollination services be alternative tools against infections? Today, due to the emerging antibiotic-resistant pathogens, we are facing a new era of searching for alternative tools against infections. Natural products such as honey have been applied against human's infections for millennia without sufficient scientific evidence. A unique lactic acid bacterial (LAB) microbiota was discovered by us, which is in symbiosis with honeybees and present in large amounts in fresh honey across the world. This work investigates if the LAB symbionts are the source to the unknown factors contributing to honey's properties. Hence, we tested the LAB against severe wound pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and vancomycin-resistant Enterococcus (VRE) among others. We demonstrate a strong antimicrobial activity from each symbiont and a synergistic effect, which counteracted all the tested pathogens. The mechanisms of action are partly shown by elucidating the production of active compounds such as proteins, fatty acids, anaesthetics, organic acids, volatiles and hydrogen peroxide. We show that the symbionts produce a myriad of active compounds that remain in variable amounts in mature honey. Further studies are now required to investigate if these symbionts have a potential in clinical applications as alternative tools against topical human and animal infections.

  7. Silver residues as a possible key to a remarkable oxidative catalytic activity of nanoporous gold.

    PubMed

    Moskaleva, Lyudmila V; Röhe, Sarah; Wittstock, Arne; Zielasek, Volkmar; Klüner, Thorsten; Neyman, Konstantin M; Bäumer, Marcus

    2011-03-14

    Recently, several forms of unsupported gold were shown to display a remarkable activity to catalyze oxidation reactions. Experimental evidence points to the crucial role of residual silver present in very small concentrations in these novel catalysts. We focus on the catalytic properties of nanoporous gold (np-Au) foams probed via CO and oxygen adsorption/co-adsorption. Experimental results are analyzed using theoretical models represented by the flat Au(111) and the kinked Au(321) slabs with Ag impurities. We show that Ag atoms incorporated into gold surfaces can facilitate the adsorption and dissociation of molecular oxygen on them. CO adsorbed on top of 6-fold coordinated Au atoms can in turn be stabilized by co-adsorbed atomic oxygen by up to 0.2 eV with respect to the clean unsubstituted gold surface. Our experiments suggest a linking of that most strongly bound CO adsorption state to the catalytic activity of np-Au. Thus, our results shed light on the role of silver admixtures in the striking catalytic activity of unsupported gold nanostructures.

  8. p38 mitogen-activated protein kinase plays a key role in regulating MAPKAPK2 expression

    SciTech Connect

    Sudo, Tatsuhiko . E-mail: sudo@riken.jp; Kawai, Kayoko; Matsuzaki, Hiroshi; Osada, Hiroyuki

    2005-11-18

    One of three major families of the mitogen-activated kinases (MAPK), p38 as well as JNK, has been shown to transduce extracellular stress stimuli into cellular responses by phospho-relay cascades. Among p38 families, p38{alpha} is a widely characterized isoform and the biological phenomena are explained by its kinase activity regulating functions of its downstream substrates. However, its specific contributions to each phenomenon are yet not fully elucidated. For better understanding of the role of MAPKs, especially p38{alpha}, we utilized newly established mouse fibroblast cell lines originated from a p38{alpha} null mouse, namely, a parental cell line without p38{alpha} gene locus, knockout of p38{alpha} (KOP), Zeosin-resistant (ZKOP), revertant of p38{alpha} (RKOP), and Exip revertant (EKOP). EKOP is smaller in size but grows faster than the others. Although comparable amounts of ERK and JNK are expressed in each cell line, ERK is highly phosphorylated in EKOP even in normal culture conditions. Serum stimulation after serum starvation led to ERK phosphorylation in RKOP and ZKOP, but not in EKOP as much. On the contrary, relative phosphorylation level of JNK to total JNK in response to UV was low in RKOP. And its phosphorylation as well as total JNK is slightly lower in EKOP. RKOP is less sensitive to UV irradiation as judged by the survival rate. Stress response upon UV or sorbitol stimuli, leading to mitogen activate protein kinase activated kinase 2 (MAPKAPK2) phosphorylation, was only observed in RKOP. Further experiments reveal that MAPKAPK2 expression is largely suppressed in ZKOP and EKOP. Its expression was recovered by re-introduction of p38{alpha}. The loss of MAPKAPK2 expression accompanied by the defect of p38{alpha} is confirmed in an embryonic extract prepared from p38{alpha} null mice. These data demonstrate that p38 signal pathway is regulated not only by phosphorylation but also by modulation of the expression of its component. Together, we have

  9. Behavioral science in video games for children's diet and physical activity change: key research needs.

    PubMed

    Baranowski, Tom; Baranowski, Janice; Thompson, Debbe; Buday, Richard

    2011-03-01

    Innovative intervention programs are needed to overcome the limitations in previous programs that promoted change in diabetes risk behaviors in children. Serious video games show promise of changing dietary and physical activity behaviors, but research is needed on the optimal design of behavior-change procedures in video games, the mechanisms that account for changes obtained, and the groups in which these interventions work best. Such research will permit the optimal design of serious video games for diabetes and obesity prevention in the future.

  10. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    SciTech Connect

    Poulsen, Raewyn C. Carr, Andrew J.; Hulley, Philippa A.

    2015-06-19

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  11. Nitric oxide-mediated cyclooxygenase activation. A key event in the antiplatelet effects of nitrovasodilators.

    PubMed Central

    Salvemini, D; Currie, M G; Mollace, V

    1996-01-01

    We have evaluated the contributions of nitric oxide (NO) and prostacyclin (PGI2) in the in vivo antiplatelet effects of clinically useful nitrovasodilators. In rats, intravenous infusion of three NO donors, glyceryl trinitrate, sodium nitroprusside, or 3'-morpholinosydnonimine, the stable metabolite of molsidomine, released 6-keto PGF1alpha (the stable metabolite of PGI2) and inhibited ex vivo human platelet aggregation to adenosine diphosphate by at least 80%. In in vitro studies, glyceryl trinitrate, sodium nitroprusside, and 3'-morpholinosydnonimine, at clinically attainable concentrations, increased cyclooxygenase activity in endothelial cells (EC), which resulted in a four- to sixfold release of 6-keto PGF1alpha. Pretreatment of the EC with hemoglobin which binds to and inactivates the biological actions of NO, but not by methylene blue (MelB), attenuated the NO-mediated PGI2 from the EC by at least 70%. Release of 6-keto PGF1alpha by the NO donors increased the ability of these compounds to inhibit thrombin-induced human platelet aggregation by at least 10 times; this potentiation was inhibited by hemoglobin but not by MeB. MeB blocked the direct anti-platelet effect of the NO donors in the absence of EC. In summary, we have demonstrated that NO, directly as well as together with an NO-driven cyclooxygenase activation (and hence PGI2), release contributes to the marked anti-platelet effects observed after the in vivo administration of clinically used nitrovasodilators. PMID:8647949

  12. Mitochondrial ClpX activates a key enzyme for heme biosynthesis and erythropoiesis

    PubMed Central

    Kardon, Julia R.; Yien, Yvette Y.; Huston, Nicholas C.; Branco, Diana S.; Hildick-Smith, Gordon J.; Rhee, Kyu Y.; Paw, Barry H.; Baker, Tania A.

    2015-01-01

    SUMMARY The mitochondrion maintains and regulates its proteome with chaperones primarily inherited from its bacterial endosymbiont ancestor. Among these chaperones is the AAA+ unfoldase ClpX, an important regulator of prokaryotic physiology with poorly defined function in the eukaryotic mitochondrion. We observed phenotypic similarity in S. cerevisiae genetic interaction data between mitochondrial ClpX (mtClpX) and genes contributing to heme biosynthesis, an essential mitochondrial function. Metabolomic analysis revealed that 5-aminolevulinic acid (ALA), the first heme precursor, is five-fold reduced in yeast lacking mtClpX activity, and total heme is reduced by half. mtClpX directly stimulates ALA synthase in vitro by catalyzing incorporation of its cofactor, pyridoxal phosphate. This activity is conserved in mammalian homologs; additionally, mtClpX depletion impairs vertebrate erythropoiesis, which requires massive upregulation of heme biosynthesis to supply hemoglobin. mtClpX therefore is a widely conserved stimulator of an essential biosynthetic pathway, and employs a previously unrecognized mechanism for AAA+ unfoldases. PMID:25957689

  13. The stellar wind as a key to the understanding of the spectral activity of IN Com

    NASA Astrophysics Data System (ADS)

    Kozlova, O. V.; Alekseev, I. Yu.

    2014-06-01

    We present long-term spectral observations ( R = 20000) of IN Com in the region of the Hα, Hβ, and He I 5876 lines. One distinguishing characteristic of the stellar spectrum is the presence in the Hα line of an extended two-component emission with limits up to ±400 km/s. Emission parameters show the rotation modulation with the stellar rotation period and a significant variability on the long-term scale. Similar emissions are also observed in the Hβ and He I 5876 lines. Our results allow us to conclude that observational emission profiles are formed in an optically thin hot gas. This is a result of the presence of a circumstellar gas disk around IN Com. Its size does not exceed several stellar radii. The material for the disk is supported by the stellar wind from IN Com. The detected variability of Hα-emission parameters shows a clear connection with the photopolarimetric activity of the star. This fact allows us to associate the long-term spectral variability with cycles of stellar activity of IN Com.

  14. KEY COMPARISON: BIPM comparison BIPM.RI(II)-K1.Rn-222 of activity measurements of the radionuclide 222Rn

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Bochud, F. O.

    2004-01-01

    Since 2001, a national metrology institute, the Institut de Radiophysique Appliquée (IRA), Switzerland, has submitted two samples of known activity of 222Rn to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM). The activities ranged from about 13 kBq to 370 kBq. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), with comparison identifier BIPM.RI(II)-K1.Rn-222, according to the provisions of the Mutual Recognition Arrangement (MRA).

  15. National Low-Level Waste Management Program final summary report of key activities and accomplishments for fiscal year 1997

    SciTech Connect

    Rittenberg, R.B.

    1998-03-01

    The US Department of Energy (DOE) has responsibilities under the Low-Level Radioactive Waste Policy Amendments Act of 1985 to assist states and compacts in their siting and licensing efforts for low-level radioactive waste disposal facilities. The National Low-Level Waste Management Program (NLLWMP) is the element of the DOE that performs the key support activities under the Act. The NLLWMP`s activities are driven by the needs of the states and compacts as they prepare to manage their low-level waste under the Act. Other work is added during the fiscal year as necessary to accommodate new requests brought on by status changes in states` and compacts` siting and licensing efforts. This report summarizes the activities and accomplishments of the NLLWMP during FY 1997.

  16. Activities of Daily Living in Mexican American Caregivers: The Key to Continuing Informal Care

    PubMed Central

    Evans, Bronwynne C.; Belyea, Michael J.; Coon, David W.; Ume, Ebere

    2013-01-01

    La familia drives elder care in Mexican–American (MA) families, but nursing home placement can result from day-to-day caregiving demands that increase caregiver difficulty with activities of daily living (ADLs). Using life course perspective, this article describes the initial data wave of 31 MA caregivers from a descriptive, longitudinal, mixed-methods study of 110 MA caregivers and care recipients over 15 months in their caregiving trajectories. Fifteen of 31 caregivers consistently indicated “no help needed” on the Katz ADL, whereas all but one reported “help needed” during semistructured interviews with cultural brokers. In addition to the discrepancy between results on the Katz ADL and interviews, findings include consideration of nursing home placement by moderately acculturated caregivers and minimization of their illnesses by caregivers. Additional methods of MA caregiver assessment may be needed due to the questionable accuracy of the Katz ADL; additional research should explore minimization and acculturation in MA caregivers. PMID:22740307

  17. The flavonoid paradox: conjugation and deconjugation as key steps for the biological activity of flavonoids.

    PubMed

    Perez-Vizcaino, Francisco; Duarte, Juan; Santos-Buelga, Celestino

    2012-07-01

    Flavonoids have been proposed to exert beneficial effects in the prevention of a large number of diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. Paradoxically, despite the most representative flavonoid--quercetin--exerting biologically demonstrable systemic effects, it is not found in plasma after oral administration and its circulating metabolites show weak activity in vitro. The current available evidence indicates that quercetin is extensively metabolized into methylated and glucurono- and sulfo-conjugated metabolites, which are the plasma circulating forms; and glucurono-, but not sulfo-conjugates, can be hydrolyzed at the vascular level, yielding the parent aglycone which accumulates in tissues. Thus conjugation is a reversible process and, at least regarding the vasodilator and antihypertensive effects, the conjugation-deconjugation cycle appears to be an absolute requirement. Glucuronidated derivatives transport quercetin and its methylated form, and deliver to the tissues the free aglycone, which is the final effector.

  18. Activation of the immune response is a key feature of aging in mice.

    PubMed

    Brink, Thore C; Regenbrecht, Christian; Demetrius, Lloyd; Lehrach, Hans; Adjaye, James

    2009-12-01

    The process of aging is complex involving numerous factors centered on transcriptional changes with advanced age. This study was aimed at elucidating mechanisms involved in mouse aging by conducting both gene expression and biochemical analyses on isolated mouse brain, heart and kidney. The gene expression analysis was not aimed at solely highlighting age-related transcriptional changes but also revealing regulated biological processes, cellular compartments, signaling and metabolic pathways. We have uncovered a conserved increase in the expression of genes mediating immune responses in all the tissues analyzed. In addition, elevated levels of lipid hydroperoxides (LPO)—an indicator of increased levels of radical oxygen species, implicate an oxidative stress-mediated activity of NF-kB signaling. In summary, these results suggest that transcriptional changes are most probably the downstream effect of environmental and endogenous factors constantly affecting the organism during its lifetime. In addition, we propose LPO as a potential biomarker of aging.

  19. Reducing conditions are the key for efficient production of active ribonuclease inhibitor in Escherichia coli

    PubMed Central

    2011-01-01

    Background The eukaryotic RNase ribonuclease/angiogenin inhibitors (RI) are a protein group distinguished by a unique structure - they are composed of hydrophobic leucine-rich repeat motifs (LRR) and contain a high amount of reduced cysteine residues. The members of this group are difficult to produce in E. coli and other recombinant hosts due to their high aggregation tendency. Results In this work dithiothreitol (DTT) was successfully applied for improving the yield of correctly folded ribonuclease/angiogenin inhibitor in E. coli K12 periplasmic and cytoplasmic compartments. The feasibility of the in vivo folding concepts for cytoplasmic and periplasmic production were demonstrated at batch and fed-batch cultivation modes in shake flasks and at the bioreactor scale. Firstly, the best secretion conditions of RI in the periplasmic space were evaluated by using a high throughput multifactorial screening approach of a vector library, directly with the Enbase fed-batch production mode in 96-well plates. Secondly, the effect of the redox environment was evaluated in isogenic dsbA+ and dsbA- strains at the various cultivation conditions with reducing agents in the cultivation medium. Despite the fusion to the signal peptide, highest activities were found in the cytoplasmic fraction. Thus by removing the signal peptide the positive effect of the reducing agent DTT was clearly proven also for the cytoplasmic compartment. Finally, optimal periplasmic and cytoplasmic RI fed-batch production processes involving externally added DTT were developed in shake flasks and scaled up to the bioreactor scale. Conclusions DTT highly improved both, periplasmic and cytoplasmic accumulation and activity of RI at low synthesis rate, i.e. in constructs harbouring weak recombinant synthesis rate stipulating genetic elements together with cultivation at low temperature. In a stirred bioreactor environment RI folding was strongly improved by repeated pulse addition of DTT at low aeration

  20. Carotenoid derivatives inhibit nuclear factor kappa B activity in bone and cancer cells by targeting key thiol groups.

    PubMed

    Linnewiel-Hermoni, Karin; Motro, Yair; Miller, Yifat; Levy, Joseph; Sharoni, Yoav

    2014-10-01

    Aberrant activation of the nuclear factor kappa B (NFkB) transcription system contributes to cancer progression, and has a harmful effect on bone health. Several major components of the NFkB pathway such as IkB Kinase (IKK) and the NFkB subunits contain cysteine residues that are critical for their activity. The interaction of electrophiles with these cysteine residues results in NFkB inhibition. Carotenoids, hydrophobic plant pigments, are devoid of electrophilic groups, and we have previously demonstrated that carotenoid derivatives, but not the native compounds activate the Nrf2 transcription system. The aim of the current study was to examine whether carotenoid derivatives inhibit NFkB, and, if so, to determine the molecular mechanism underpinning the inhibitory action. We report in the present study that a mixture of oxidized derivatives, prepared by ethanol extraction from partially oxidized lycopene preparation, inhibited NFkB reporter gene activity. In contrast, the intact carotenoid was inactive. A series of synthetic dialdehyde carotenoid derivatives inhibited reporter activity as well as several stages of the NFkB pathway in both cancer and bone cells. The activity of the carotenoid derivatives depended on the reactivity of the electrophilic groups in reactions such as Michael addition to sulfhydryl groups of proteins. Specifically, carotenoid derivatives directly interacted with two key proteins of the NFkB pathway: the IKKβ and the p65 subunit. Direct interaction with IKKβ was found in an in vitro kinase assay with a recombinant enzyme. The inhibition by carotenoid derivatives of p65 transcriptional activity was observed in a reporter gene assay performed in the presence of excess p65. This inhibition action resulted, at least in part, from direct interaction of the carotenoid derivative with p65 leading to reduced binding of the protein to DNA as evidenced by electrophoretic mobility shift assay (EMSA) experiments. Importantly, we found by using

  1. Sight-Word Practice in a Flash!

    ERIC Educational Resources Information Center

    Erwin, Robin W., Jr.

    2016-01-01

    For learners who need sight-word practice, including young students and struggling readers, digital flash cards may promote automatic word recognition when used as a supplemental activity to regular reading instruction. A novel use of common presentation software efficiently supports this practice strategy.

  2. Efficient production of optically pure L-lactic acid from food waste at ambient temperature by regulating key enzyme activity.

    PubMed

    Li, Xiang; Chen, Yinguang; Zhao, Shu; Chen, Hong; Zheng, Xiong; Luo, Jinyang; Liu, Yanan

    2015-03-01

    Bio-production of optically pure L-lactic acid from food waste has attracted much interest as it can treat organic wastes with simultaneous recovery of valuable by-products. However, the yield of L-lactic acid was very low and no optically pure L-lactic acid was produced in the literature due to (1) the lower activity of enzymes involved in hydrolysis and L-lactic acid generation, and (2) the participation of other enzymes related to D-lactic acid and acetic and propionic acids production. In this paper, a new strategy was reported for effective production of optically pure L-lactic acid from food waste at ambient temperature, i.e. via regulating key enzyme activity by sewage sludge supplement and intermittent alkaline fermentation. It was found that not only optically pure L-lactic acid was produced, but the yield was enhanced by 2.89-fold. The mechanism study showed that the activities of enzymes relevant to food waste hydrolysis and lactic acid production were enhanced, and the key enzymes related to volatile fatty acids and D-lactic acid generations were severally decreased or inhibited. Also, the microbes responsible for L-lactic acid production were selectively proliferated. Finally, the pilot-scale continuous experiment was conducted to testify the feasibility of this new technique.

  3. How to Tackle Key Challenges in the Promotion of Physical Activity among Older Adults (65+): The AEQUIPA Network Approach.

    PubMed

    Forberger, Sarah; Bammann, Karin; Bauer, Jürgen; Boll, Susanne; Bolte, Gabriele; Brand, Tilman; Hein, Andreas; Koppelin, Frauke; Lippke, Sonia; Meyer, Jochen; Pischke, Claudia R; Voelcker-Rehage, Claudia; Zeeb, Hajo

    2017-04-04

    The paper introduces the theoretical framework and methods/instruments used by the Physical Activity and Health Equity: Primary Prevention for Healthy Ageing (AEQUIPA) prevention research network as an interdisciplinary approach to tackle key challenges in the promotion of physical activity among older people (65+). Drawing on the social-ecological model, the AEQUIPA network developed an interdisciplinary methodological design including quantitative/qualitative studies and systematic reviews, while combining expertise from diverse fields: public health, psychology, urban planning, sports sciences, health technology and geriatrics. AEQUIPA tackles key challenges when promoting physical activity (PA) in older adults: tailoring of interventions, fostering community readiness and participation, strengthening intersectoral collaboration, using new technological devices and evaluating intervention generated inequalities. AEQUIPA aims to strengthen the evidence base for age-specific preventive PA interventions and to yield new insights into the explanatory power of individual and contextual factors. Currently, the empirical work is still underway. First experiences indicate that thenetwork has achieved a strong regional linkage with communities, local stakeholders and individuals. However, involving inactive persons and individuals from minority groups remained challenging. A review of existing PA intervention studies among the elderly revealed the potential to assess equity effects. The results will add to the theoretical and methodological discussion on evidence-based age-specific PA interventions and will contribute to the discussion about European and national health targets.

  4. HIV-1 Nef Impairs Key Functional Activities in Human Macrophages through CD36 Downregulation

    PubMed Central

    Olivetta, Eleonora; Tirelli, Valentina; Chiozzini, Chiara; Scazzocchio, Beatrice; Romano, Ignazio; Arenaccio, Claudia; Sanchez, Massimo

    2014-01-01

    Monocytes and macrophages utilize the class A and B scavenger receptors to recognize and perform phagocytosis of invading microbes before a pathogen-specific immune response is generated. HIV-1 Nef protein affects the innate immune system impairing oxidative burst response and phagocytic capacity of macrophages. Our data show that exogenous recombinant myristoylated Nef protein induces a marked CD36 downregulation in monocytes from Peripheral Blood Mononuclear Cells, in Monocyte-Derived Macrophages (MDMs) differentiated by cytokines and in MDMs contained in a mixed culture obtained expanding PBMCs under Human Erythroid Massive Amplification condition. Under the latter culture condition we identify three main populations after 6 days of expansion: lymphocytes (37.8±14.7%), erythroblasts (46.7±6.1%) and MDMs (15.7±7.5%). The Nef addition to the cell culture significantly downregulates CD36 expression in MDMs, but not in erythroid cells. Furthermore, CD36 inhibition is highly specific since it does not modify the expression levels of other MDM markers such as CD14, CD11c, CD86, CD68, CD206, Toll-like Receptor 2 and Toll-like Receptor 4. Similar results were obtained in MDMs infected with VSV-G pseudotyped HIV-1-expressing Nef. The reduced CD36 membrane expression is associated with decrease of correspondent CD36 mRNA transcript. Furthermore, Nef-induced CD36 downregulation is linked to both impaired scavenger activity with reduced capability to take up oxidized lipoproteins and to significant decreased phagocytosis of fluorescent beads and GFP-expressing Salmonella tiphymurium. In addition we observed that Nef induces TNF-α release in MDMs. Although these data suggest a possible involvement of TNF-α in mediating Nef activity, our results exclude a possible relationship between Nef-induced TNF-α release and Nef-mediated CD36 downregulation. The present work shows that HIV-1 Nef protein may have a role in the strategies elaborated by HIV-1 to alter pathogen

  5. Key Role of Active-Site Water Molecules in Bacteriorhodopsin Proton-Transfer Reactions

    SciTech Connect

    Bondar, A.N.; Baudry, Jerome Y; Suhai, Sandor; Fischer, S.; Smith, Jeremy C

    2008-10-01

    The functional mechanism of the light-driven proton pump protein bacteriorhodopsin depends on the location of water molecules in the active site at various stages of the photocycle and on their roles in the proton-transfer steps. Here, free energy computations indicate that electrostatic interactions favor the presence of a cytoplasmic-side water molecule hydrogen bonding to the retinal Schiff base in the state preceding proton transfer from the retinal Schiff base to Asp85. However, the nonequilibrium nature of the pumping process means that the probability of occupancy of a water molecule in a given site depends both on the free energies of insertion of the water molecule in this and other sites during the preceding photocycle steps and on the kinetic accessibility of these sites on the time scale of the reaction steps. The presence of the cytoplasmic-side water molecule has a dramatic effect on the mechanism of proton transfer: the proton is channeled on the Thr89 side of the retinal, whereas the transfer on the Asp212 side is hindered. Reaction-path simulations and molecular dynamics simulations indicate that the presence of the cytoplasmic-side water molecule permits a low-energy bacteriorhodopsin conformer in which the water molecule bridges the twisted retinal Schiff base and the proton acceptor Asp85. From this low-energy conformer, proton transfer occurs via a concerted mechanism in which the water molecule participates as an intermediate proton carrier.

  6. PDF neuron firing phase-shifts key circadian activity neurons in Drosophila.

    PubMed

    Guo, Fang; Cerullo, Isadora; Chen, Xiao; Rosbash, Michael

    2014-06-17

    Our experiments address two long-standing models for the function of the Drosophila brain circadian network: a dual oscillator model, which emphasizes the primacy of PDF-containing neurons, and a cell-autonomous model for circadian phase adjustment. We identify five different circadian (E) neurons that are a major source of rhythmicity and locomotor activity. Brief firing of PDF cells at different times of day generates a phase response curve (PRC), which mimics a light-mediated PRC and requires PDF receptor expression in the five E neurons. Firing also resembles light by causing TIM degradation in downstream neurons. Unlike light however, firing-mediated phase-shifting is CRY-independent and exploits the E3 ligase component CUL-3 in the early night to degrade TIM. Our results suggest that PDF neurons integrate light information and then modulate the phase of E cell oscillations and behavioral rhythms. The results also explain how fly brain rhythms persist in constant darkness and without CRY.

  7. PLASMINOGEN ACTIVATOR INHIBITOR-1 (PAI-1): A KEY FACTOR LINKING FIBRINOLYSIS AND AGE-RELATED SUBCLINICAL AND CLINICAL CONDITIONS

    PubMed Central

    Cesari, Matteo; Pahor, Marco; Incalzi, Raffaele Antonelli

    2010-01-01

    The close relationship existing between aging and thrombosis has growingly been studied in this last decade. The age-related development of a pro-thrombotic imbalance in the fibrinolysis homeostasis has been hypothesized at the basis of this increased cardiovascular and cerebrovascular risk. Fibrinolysis is the resulting of the interactions among multiple plasminogen activators and inhibitors constituing the enzymatic cascade, and ultimately leading to the degradation of fibrin. The plasminogen activator system plays a key role in a wide range of physiological and pathological processes. Plasminogen activator inhibitor-1 (PAI-1) is a member of the superfamily of serine-protease inhibitors (or serpins), and the principal inhibitor of both the tissue-type and the urinary-type plasminogen activator, the two plasminogen activators able to activate plasminogen. In this review, current evidence describing the central role played by PAI-1 in a number of age-related subclinical (i.e., inflammation, atherosclerosis, insulin resistance) and clinical (i.e., obesity, comorbidities, Werner syndrome) conditions is presented. Despite some controversial and unclear issues, PAI-1 represents an extremely promising marker which may become a biological parameter to be growingly considered in the prognostic evaluation, in the disease monitoring, and as treatment target of age-related conditions in the next future. PMID:20626406

  8. A Detailed Data-Driven Network Model of Prefrontal Cortex Reproduces Key Features of In Vivo Activity

    PubMed Central

    Hass, Joachim; Hertäg, Loreen; Durstewitz, Daniel

    2016-01-01

    The prefrontal cortex is centrally involved in a wide range of cognitive functions and their impairment in psychiatric disorders. Yet, the computational principles that govern the dynamics of prefrontal neural networks, and link their physiological, biochemical and anatomical properties to cognitive functions, are not well understood. Computational models can help to bridge the gap between these different levels of description, provided they are sufficiently constrained by experimental data and capable of predicting key properties of the intact cortex. Here, we present a detailed network model of the prefrontal cortex, based on a simple computationally efficient single neuron model (simpAdEx), with all parameters derived from in vitro electrophysiological and anatomical data. Without additional tuning, this model could be shown to quantitatively reproduce a wide range of measures from in vivo electrophysiological recordings, to a degree where simulated and experimentally observed activities were statistically indistinguishable. These measures include spike train statistics, membrane potential fluctuations, local field potentials, and the transmission of transient stimulus information across layers. We further demonstrate that model predictions are robust against moderate changes in key parameters, and that synaptic heterogeneity is a crucial ingredient to the quantitative reproduction of in vivo-like electrophysiological behavior. Thus, we have produced a physiologically highly valid, in a quantitative sense, yet computationally efficient PFC network model, which helped to identify key properties underlying spike time dynamics as observed in vivo, and can be harvested for in-depth investigation of the links between physiology and cognition. PMID:27203563

  9. A Detailed Data-Driven Network Model of Prefrontal Cortex Reproduces Key Features of In Vivo Activity.

    PubMed

    Hass, Joachim; Hertäg, Loreen; Durstewitz, Daniel

    2016-05-01

    The prefrontal cortex is centrally involved in a wide range of cognitive functions and their impairment in psychiatric disorders. Yet, the computational principles that govern the dynamics of prefrontal neural networks, and link their physiological, biochemical and anatomical properties to cognitive functions, are not well understood. Computational models can help to bridge the gap between these different levels of description, provided they are sufficiently constrained by experimental data and capable of predicting key properties of the intact cortex. Here, we present a detailed network model of the prefrontal cortex, based on a simple computationally efficient single neuron model (simpAdEx), with all parameters derived from in vitro electrophysiological and anatomical data. Without additional tuning, this model could be shown to quantitatively reproduce a wide range of measures from in vivo electrophysiological recordings, to a degree where simulated and experimentally observed activities were statistically indistinguishable. These measures include spike train statistics, membrane potential fluctuations, local field potentials, and the transmission of transient stimulus information across layers. We further demonstrate that model predictions are robust against moderate changes in key parameters, and that synaptic heterogeneity is a crucial ingredient to the quantitative reproduction of in vivo-like electrophysiological behavior. Thus, we have produced a physiologically highly valid, in a quantitative sense, yet computationally efficient PFC network model, which helped to identify key properties underlying spike time dynamics as observed in vivo, and can be harvested for in-depth investigation of the links between physiology and cognition.

  10. Strong Nonadditivity as a Key Structure–Activity Relationship Feature: Distinguishing Structural Changes from Assay Artifacts

    PubMed Central

    2015-01-01

    Nonadditivity in protein–ligand affinity data represents highly instructive structure–activity relationship (SAR) features that indicate structural changes and have the potential to guide rational drug design. At the same time, nonadditivity is a challenge for both basic SAR analysis as well as many ligand-based data analysis techniques such as Free-Wilson Analysis and Matched Molecular Pair analysis, since linear substituent contribution models inherently assume additivity and thus do not work in such cases. While structural causes for nonadditivity have been analyzed anecdotally, no systematic approaches to interpret and use nonadditivity prospectively have been developed yet. In this contribution, we lay the statistical framework for systematic analysis of nonadditivity in a SAR series. First, we develop a general metric to quantify nonadditivity. Then, we demonstrate the non-negligible impact of experimental uncertainty that creates apparent nonadditivity, and we introduce techniques to handle experimental uncertainty. Finally, we analyze public SAR data sets for strong nonadditivity and use recourse to the original publications and available X-ray structures to find structural explanations for the nonadditivity observed. We find that all cases of strong nonadditivity (ΔΔpKi and ΔΔpIC50 > 2.0 log units) with sufficient structural information to generate reasonable hypothesis involve changes in binding mode. With the appropriate statistical basis, nonadditivity analysis offers a variety of new attempts for various areas in computer-aided drug design, including the validation of scoring functions and free energy perturbation approaches, binding pocket classification, and novel features in SAR analysis tools. PMID:25760829

  11. A historical analysis of Plinian unrest and the key promoters of explosive activity.

    NASA Astrophysics Data System (ADS)

    Winson, A. E. G.; Newhall, C. G.; Costa, F.

    2015-12-01

    Plinian eruptions are the largest historically recorded volcanic phenomena, and have the potential to be widely destructive. Yet when a volcano becomes newly restless we are unable to anticipate whether or not a large eruption is imminent. We present the findings from a multi-parametric study of 42 large explosive eruptions (29 Plinian and 13 Sub-plinian) that form the basis for a new Bayesian Belief network that addresses this question. We combine the eruptive history of the volcanoes that have produced these large eruptions with petrological studies, and reported unrest phenomena to assess the probability of an eruption being plinian. We find that the 'plinian probability' is increased most strongly by the presence of an exsolved volatile phase in the reservoir prior to an eruption. In our survey 60% of the plinian eruptions, had an excess SO2 gas phase of more than double than it is calculated by petrologic studies alone. Probability is also increased by three related and more easily observable parameters: a high plinian Ratio (that is the ratio of VEI≥4 eruptions in a volcanoes history to the number of all VEI≥2 eruptions in the history), a repose time of more than 1000 years, and a Repose Ratio (the ratio of the average return of VEI≥4 eruptions in the volcanic record to the repose time since the last VEI≥4) of greater than 0.7. We looked for unrest signals that potentially are indicative of future plinian activity and report a few observations from case studies but cannot say if these will generally appear. Finally we present a retrospective analysis of the probabilities of eruptions in our study becoming plinian, using our Bayesian belief network. We find that these probabilities are up to about 4 times greater than those calculate from an a priori assessment of the global eruptive catalogue.

  12. Structural effects of nucleobase variations at key active site residue Ade38 in the hairpin ribozyme

    PubMed Central

    MacElrevey, Celeste; Salter, Jason D.; Krucinska, Jolanta; Wedekind, Joseph E.

    2008-01-01

    The hairpin ribozyme requires functional groups from Ade38 to achieve efficient bond cleavage or ligation. To identify molecular features that contribute to catalysis, structures of position 38 base variants 2,6-diaminopurine (DAP), 2-aminopurine (AP), cytosine (Cyt), and guanine (Gua) were determined between 2.2 and 2.8 Å resolution. For each variant, two substrate modifications were compared: (1) a 2′-O-methyl-substituent at Ade-1 was used in lieu of the nucleophile to mimic the precatalytic state, and (2) a 3′-deoxy-2′,5′-phosphodiester linkage between Ade-1 and Gua+1 was used to mimic a reaction-intermediate conformation. While the global fold of each variant remained intact, the results revealed the importance of Ade38 N1 and N6 groups. Absence of N6 resulting from AP38 coincided with failure to localize the precatalytic scissile phosphate. Cyt38 severely impaired catalysis in a prior study, and its structures here indicated an anti base conformation that sequesters the imino moiety from the scissile bond. Gua38 was shown to be even more deleterious to activity. Although the precatalytic structure was nominally affected, the reaction-intermediate conformation indicated a severe electrostatic clash between the Gua38 keto oxygen and the pro-Rp oxygen of the scissile bond. Overall, position 38 modifications solved in the presence of 2′-OMe Ade-1 deviated from in-line geometry, whereas variants with a 2′,5′ linkage exhibited S-turn destabilization, as well as base conformational changes from syn to anti. These findings demonstrate the importance of the Ade38 Watson–Crick face in attaining a reaction-intermediate state and the sensitivity of the RNA fold to restructuring when electrostatic and shape features fail to complement. PMID:18596253

  13. The Write Way: Saving Words Pays High Interest.

    ERIC Educational Resources Information Center

    Evans, George P.

    1994-01-01

    Compares an "uncluttered" writing portfolio to a wise investment. Describes methods for saving words, or "tightening" an essay, such as using firm verbs and nouns, maneuvering active and passive tense, and making every word count. (PA)

  14. Mitochondrial Activity and Cyr1 Are Key Regulators of Ras1 Activation of C. albicans Virulence Pathways

    PubMed Central

    Grahl, Nora; Demers, Elora G.; Lindsay, Allia K.; Harty, Colleen E.; Willger, Sven D.; Piispanen, Amy E.; Hogan, Deborah A.

    2015-01-01

    Candida albicans is both a major fungal pathogen and a member of the commensal human microflora. The morphological switch from yeast to hyphal growth is associated with disease and many environmental factors are known to influence the yeast-to-hyphae switch. The Ras1-Cyr1-PKA pathway is a major regulator of C. albicans morphogenesis as well as biofilm formation and white-opaque switching. Previous studies have shown that hyphal growth is strongly repressed by mitochondrial inhibitors. Here, we show that mitochondrial inhibitors strongly decreased Ras1 GTP-binding and activity in C. albicans and similar effects were observed in other Candida species. Consistent with there being a connection between respiratory activity and GTP-Ras1 binding, mutants lacking complex I or complex IV grew as yeast in hypha-inducing conditions, had lower levels of GTP-Ras1, and Ras1 GTP-binding was unaffected by respiratory inhibitors. Mitochondria-perturbing agents decreased intracellular ATP concentrations and metabolomics analyses of cells grown with different respiratory inhibitors found consistent perturbation of pyruvate metabolism and the TCA cycle, changes in redox state, increased catabolism of lipids, and decreased sterol content which suggested increased AMP kinase activity. Biochemical and genetic experiments provide strong evidence for a model in which the activation of Ras1 is controlled by ATP levels in an AMP kinase independent manner. The Ras1 GTPase activating protein, Ira2, but not the Ras1 guanine nucleotide exchange factor, Cdc25, was required for the reduction of Ras1-GTP in response to inhibitor-mediated reduction of ATP levels. Furthermore, Cyr1, a well-characterized Ras1 effector, participated in the control of Ras1-GTP binding in response to decreased mitochondrial activity suggesting a revised model for Ras1 and Cyr1 signaling in which Cyr1 and Ras1 influence each other and, together with Ira2, seem to form a master-regulatory complex necessary to integrate

  15. Where’s the Noise? Key Features of Spontaneous Activity and Neural Variability Arise through Learning in a Deterministic Network

    PubMed Central

    Hartmann, Christoph; Lazar, Andreea; Nessler, Bernhard; Triesch, Jochen

    2015-01-01

    Even in the absence of sensory stimulation the brain is spontaneously active. This background “noise” seems to be the dominant cause of the notoriously high trial-to-trial variability of neural recordings. Recent experimental observations have extended our knowledge of trial-to-trial variability and spontaneous activity in several directions: 1. Trial-to-trial variability systematically decreases following the onset of a sensory stimulus or the start of a motor act. 2. Spontaneous activity states in sensory cortex outline the region of evoked sensory responses. 3. Across development, spontaneous activity aligns itself with typical evoked activity patterns. 4. The spontaneous brain activity prior to the presentation of an ambiguous stimulus predicts how the stimulus will be interpreted. At present it is unclear how these observations relate to each other and how they arise in cortical circuits. Here we demonstrate that all of these phenomena can be accounted for by a deterministic self-organizing recurrent neural network model (SORN), which learns a predictive model of its sensory environment. The SORN comprises recurrently coupled populations of excitatory and inhibitory threshold units and learns via a combination of spike-timing dependent plasticity (STDP) and homeostatic plasticity mechanisms. Similar to balanced network architectures, units in the network show irregular activity and variable responses to inputs. Additionally, however, the SORN exhibits sequence learning abilities matching recent findings from visual cortex and the network’s spontaneous activity reproduces the experimental findings mentioned above. Intriguingly, the network’s behaviour is reminiscent of sampling-based probabilistic inference, suggesting that correlates of sampling-based inference can develop from the interaction of STDP and homeostasis in deterministic networks. We conclude that key observations on spontaneous brain activity and the variability of neural responses can be

  16. Disk-driven hydromagnetic winds as a key ingredient of active galactic nuclei unification schemes

    NASA Technical Reports Server (NTRS)

    Konigl, Arieh; Kartje, John F.

    1994-01-01

    Centrifugally driven winds from the surfaces of magnetized accretion disks have been recognized as an attractive mechanism of removing the angular momentum of the accreted matter and of producing the bipolar outflows and jets that are often associated with compact astronomical objects. As previously suggested in the context of young stellar objects, such winds have unique observational manifestations stemming from their highly stratified density and velocity structure and from their exposure to the strong continuum radiation field of the compact object. We have applied this scenario to active galactic nuclei (AGNs) and investigated the properties of hydromagnetic outflows that originate within approximately 10(M(sub 8)) pc of the central 10(exp 8)(M(sub 8)) solar mass black hole. On the basis of our results, we propose that hydromagnetic disk-driven winds may underlie the classification of broad-line and narrow-line AGNs (e.g., the Seyfert 1/Seyfert 2 dichotomy) as well as the apparent dearth of luminous Seyfert 2 galaxies. More generally, we demonstrate that such winds could strongly influence the spectral characteristics of Seyfert galaxies, QSOs, and BL Lac objects (BLOs). In our picture, the torus is identified with the outer regions of the wind where dust uplifted from the disk surfaces by gas-grain collisions is embedded in the outflow. Using an efficient radiative transfer code, we show that the infrared emission of Seyfert galaxies and QSOs can be attributed to the reprocessing of the UV/soft X-ray AGN continuum by the dust in the wind and the disk. We demonstrate that the radiation pressure force flattens the dust distribution in objects with comparatively high (but possibly sub-Eddington) bolometric luminosities, and we propose this as one likely reason for the apparent paucity of narrow-line objects among certain high-luminosity AGNs. Using the XSTAR photoionization code, we show that the inner regions of the wind could naturally account for the warm

  17. Identification of key residues in virulent canine distemper virus hemagglutinin that control CD150/SLAM-binding activity.

    PubMed

    Zipperle, Ljerka; Langedijk, Johannes P M; Orvell, Claes; Vandevelde, Marc; Zurbriggen, Andreas; Plattet, Philippe

    2010-09-01

    Morbillivirus cell entry is controlled by hemagglutinin (H), an envelope-anchored viral glycoprotein determining interaction with multiple host cell surface receptors. Subsequent to virus-receptor attachment, H is thought to transduce a signal triggering the viral fusion glycoprotein, which in turn drives virus-cell fusion activity. Cell entry through the universal morbillivirus receptor CD150/SLAM was reported to depend on two nearby microdomains located within the hemagglutinin. Here, we provide evidence that three key residues in the virulent canine distemper virus A75/17 H protein (Y525, D526, and R529), clustering at the rim of a large recessed groove created by beta-propeller blades 4 and 5, control SLAM-binding activity without drastically modulating protein surface expression or SLAM-independent F triggering.

  18. Acquired prosopagnosia without word recognition deficits.

    PubMed

    Susilo, Tirta; Wright, Victoria; Tree, Jeremy J; Duchaine, Bradley

    2015-01-01

    It has long been suggested that face recognition relies on specialized mechanisms that are not involved in visual recognition of other object categories, including those that require expert, fine-grained discrimination at the exemplar level such as written words. But according to the recently proposed many-to-many theory of object recognition (MTMT), visual recognition of faces and words are carried out by common mechanisms [Behrmann, M., & Plaut, D. C. ( 2013 ). Distributed circuits, not circumscribed centers, mediate visual recognition. Trends in Cognitive Sciences, 17, 210-219]. MTMT acknowledges that face and word recognition are lateralized, but posits that the mechanisms that predominantly carry out face recognition still contribute to word recognition and vice versa. MTMT makes a key prediction, namely that acquired prosopagnosics should exhibit some measure of word recognition deficits. We tested this prediction by assessing written word recognition in five acquired prosopagnosic patients. Four patients had lesions limited to the right hemisphere while one had bilateral lesions with more pronounced lesions in the right hemisphere. The patients completed a total of seven word recognition tasks: two lexical decision tasks and five reading aloud tasks totalling more than 1200 trials. The performances of the four older patients (3 female, age range 50-64 years) were compared to those of 12 older controls (8 female, age range 56-66 years), while the performances of the younger prosopagnosic (male, 31 years) were compared to those of 14 younger controls (9 female, age range 20-33 years). We analysed all results at the single-patient level using Crawford's t-test. Across seven tasks, four prosopagnosics performed as quickly and accurately as controls. Our results demonstrate that acquired prosopagnosia can exist without word recognition deficits. These findings are inconsistent with a key prediction of MTMT. They instead support the hypothesis that face

  19. Effects of gas periodic stimulation on key enzyme activity in gas double-dynamic solid state fermentation (GDD-SSF).

    PubMed

    Chen, Hongzhang; Shao, Meixue; Li, Hongqiang

    2014-03-05

    The heat and mass transfer have been proved to be the important factors in air pressure pulsation for cellulase production. However, as process of enzyme secretion, the cellulase formation has not been studied in the view of microorganism metabolism and metabolic key enzyme activity under air pressure pulsation condition. Two fermentation methods in ATPase activity, cellulase productivity, weight lose rate and membrane permeability were systematically compared. Results indicated that gas double-dynamic solid state fermentation had no obviously effect on cell membrane permeability. However, the relation between ATPase activity and weight loss rate was linearly dependent with r=0.9784. Meanwhile, the results also implied that gas periodic stimulation had apparently strengthened microbial metabolism through increasing ATPase activity during gas double-dynamic solid state fermentation, resulting in motivating the production of cellulase by Trichoderma reesei YG3. Therefore, the increase of ATPase activity would be another crucial factor to strengthen fermentation process for cellulase production under gas double-dynamic solid state fermentation.

  20. Photocatalytic Properties of TiO2: Evidence of the Key Role of Surface Active Sites in Water Oxidation.

    PubMed

    Bak, Tadeusz; Li, Wenxian; Nowotny, Janusz; Atanacio, Armand J; Davis, Joel

    2015-09-10

    Photocatalytic activity of oxide semiconductors is commonly considered in terms of the effect of the band gap on the light-induced performance. The present work considers a combined effect of several key performance-related properties (KPPs) on photocatalytic activity of TiO2 (rutile), including the chemical potential of electrons (Fermi level), the concentration of surface active sites, and charge transport, in addition to the band gap. The KPPs have been modified using defect engineering. This approach led to imposition of different defect disorders and the associated KPPs, which are defect-related. This work shows, for the first time, a competitive influence of different KPPs on photocatalytic activity that was tested using oxidation of methylene blue (MB). It is shown that the increase of oxygen activity in the TiO2 lattice from 10(-12) Pa to 10(5) Pa results in (i) increase in the band gap from 2.42 to 2.91 eV (direct transitions) or 2.88 to 3 eV (indirect transitions), (ii) increase in the population of surface active sites, (iii) decrease of the Fermi level, and (iv) decrease of the charge transport. It is shown that the observed changes in the photocatalytic activity are determined by two dominant KPPs: the concentration of active surface sites and the Fermi level, while the band gap and charge transport have a minor effect on the photocatalytic performance. The effect of the defect-related properties on photoreactivity of TiO2 with water is considered in terms of a theoretical model offering molecular-level insight into the process.

  1. Reduced prefrontal cortex activation in the color-word Stroop task for Chinese dyslexic children: a near-infrared spectroscopy study

    NASA Astrophysics Data System (ADS)

    Sun, Jinyan; Zhai, Jiahuan; Song, Ranran; Zou, Li; Gong, Hui

    2011-01-01

    Behavioral studies have investigated the performance of children with developmental dyslexia in conflict resolution, a function connected with the prefrontal cortex (PFC) closely. However, little is known about the prefrontal activation in conflict resolution for dyslexic children. In the present study, the involvement of the PFC in resolving conflict was evaluated for Chinese dyslexic children by means of near-infrared spectroscopy (NIRS). The NIRS instrument is a portable, continuous-wave system and can measure concentration changes of hemodynamic parameters (including oxy-, deoxy-, and total hemoglobin). Considering better sensitivity, the oxy-hemoglobin (oxy-Hb) was chosen to indicate the prefrontal activation. Ten dyslexic children and 11 normal children were recruited to perform the Chinese-character color-word Stroop task, which included the neutral and color (incongruent) tasks. In behavioral performance, both groups showed significant Stroop effect, longer response time or higher error rate for the color task. In particular, the Stroop interference effect was marginally larger for dyslexic children than normal children in response time. What's more, the two groups showed distinct pattern of oxy-Hb activation during the Stroop tasks. The normal group recruited the bilateral PFC to perform the tasks, while the dyslexic group couldn't activate the bilateral PFC in the difficult color task. Moreover, significantly less color Stroop effect was found in the left PFC for the dyslexic group, showing their disability in coping with the Stroop interference. These findings suggest that the PFC is dysfunctional in conflict resolution for Chinese dyslexic children and that NIRS can be an effective tool in neurological research and clinical application.

  2. The Internet Alert Project: spreading the word about high-risk sexual activities advertised on the Internet.

    PubMed

    Kachur, R E

    2004-11-01

    The Internet is an emerging venue for facilitating high-risk sexual behavior; in particular, use of the Internet to seek out sex partners has been shown to be associated with high-risk sexual behaviors, such as an increase in number of sexual partners and an increase in anal sex, which can increase the risk of contracting and transmitting sexually transmitted diseases (STDs) including HIV. In an effort to assist health departments around the country, the Internet Alert Project was developed to provide Centers for Disease Control and Prevention (CDC) project officers and field staff with information about Internet-advertised, high-risk sexual activities in areas that do not have access to sexually explicit material on the Internet. An evaluation was conducted to determine the utility of the Internet Alert Project, its effect on knowledge and awareness of recipients and on public health efforts. Results of the evaluation show the alerts are a useful and valuable tool. The alerts have helped to increase knowledge about sexually-related uses of the Internet and have also driven public health efforts in the field. The results also indicate the need for project areas to access information found on the Internet in order to keep up with the ever-changing behaviors of at-risk populations.

  3. A Comparison of Word Learning in 3-Year-Old Children At-Risk for Language and Literacy Difficulties in Two Conditions: Dialogic Reading and Activity-Based Intervention

    ERIC Educational Resources Information Center

    Rahn, Naomi L.

    2013-01-01

    Existing research suggests a need for an intervention that can accelerate vocabulary acquisition for young children at-risk due to poverty. An adapted alternating treatments design was used to examine the effects of Dialogic Reading and Activity-Based Intervention (ABI) on participants' production of target words. Participants were three…

  4. The importance of delineating networks by activity type in bottlenose dolphins (Tursiops truncatus) in Cedar Key, Florida

    PubMed Central

    Gazda, Stefanie; Iyer, Swami; Killingback, Timothy; Connor, Richard; Brault, Solange

    2015-01-01

    Network analysis has proved to be a valuable tool for studying the behavioural patterns of complex social animals. Often such studies either do not distinguish between different behavioural states of the organisms or simply focus attention on a single behavioural state to the exclusion of all others. In either of these approaches it is impossible to ascertain how the behavioural patterns of individuals depend on the type of activity they are engaged in. Here we report on a network-based analysis of the behavioural associations in a population of bottlenose dolphins (Tursiops truncatus) in Cedar Key, Florida. We consider three distinct behavioural states—socializing, travelling and foraging—and analyse the association networks corresponding to each activity. Moreover, in constructing the different activity networks we do not simply record a spatial association between two individuals as being either present or absent, but rather quantify the degree of any association, thus allowing us to construct weighted networks describing each activity. The results of these weighted activity networks indicate that networks can reveal detailed patterns of bottlenose dolphins at the population level; dolphins socialize in large groups with preferential associations; travel in small groups with preferential associates; and spread out to forage in very small, weakly connected groups. There is some overlap in the socialize and travel networks but little overlap between the forage and other networks. This indicates that the social bonds maintained in other activities are less important as they forage on dispersed, solitary prey. The overall network, not sorted by activity, does not accurately represent any of these patterns. PMID:26064611

  5. Catalytic efficiency of HAP phytases is determined by a key residue in close proximity to the active site.

    PubMed

    Fu, Dawei; Li, Zhongyuan; Huang, Huoqing; Yuan, Tiezheng; Shi, Pengjun; Luo, Huiying; Meng, Kun; Yang, Peilong; Yao, Bin

    2011-05-01

    The maximum activity of Yersinia enterocolitica phytase (YeAPPA) occurs at pH 5.0 and 45 °C, and notably, its specific activity (3.28 ± 0.24 U mg(-1)) is 800-fold less than that of its Yersinia kristeensenii homolog (YkAPPA; 88% amino acid sequence identity). Sequence alignment and molecular modeling show that the arginine at position 79 (Arg79) in YeAPPA corresponding to Gly in YkAPPA as well as other histidine acid phosphatase (HAP) phytases is the only non-conserved residue near the catalytic site. To characterize the effects of the corresponding residue on the specific activities of HAP phytases, Escherichia coli EcAPPA, a well-characterized phytase with a known crystal structure, was selected for mutagenesis-its Gly73 was replaced with Arg, Asp, Glu, Ser, Thr, Leu, or Tyr. The results show that the specific activities of all of the corresponding EcAPPA mutants (17-2,400 U mg(-1)) were less than that of the wild-type phytase (3,524 U mg(-1)), and the activity levels were approximately proportional to the molecular volumes of the substituted residues' side chains. Site-directed replacement of Arg79 in YeAPPA (corresponding to Gly73 of EcAPPA) with Ser, Leu, and Gly largely increased the specific activity, which further verified the key role of the residue at position 79 for determining phytase activity. Thus, a new determinant that influences the catalytic efficiency of HAP phytases has been identified.

  6. What makes words special? Words as unmotivated cues.

    PubMed

    Edmiston, Pierce; Lupyan, Gary

    2015-10-01

    Verbal labels, such as the words "dog" and "guitar," activate conceptual knowledge more effectively than corresponding environmental sounds, such as a dog bark or a guitar strum, even though both are unambiguous cues to the categories of dogs and guitars (Lupyan & Thompson-Schill, 2012). We hypothesize that this advantage of labels emerges because word-forms, unlike other cues, do not vary in a motivated way with their referent. The sound of a guitar cannot help but inform a listener to the type of guitar making it (electric, acoustic, etc.). The word "guitar" on the other hand, can leave the type of guitar unspecified. We argue that as a result, labels gain the ability to cue a more abstract mental representation, promoting efficient processing of category members. In contrast, environmental sounds activate representations that are more tightly linked to the specific cause of the sound. Our results show that upon hearing environmental sounds such as a dog bark or guitar strum, people cannot help but activate a particular instance of a category, in a particular state, at a particular time, as measured by patterns of response times on cue-picture matching tasks (Exps. 1-2) and eye-movements in a task where the cues are task-irrelevant (Exp. 3). In comparison, labels activate concepts in a more abstract, decontextualized way-a difference that we argue can be explained by labels acting as "unmotivated cues".

  7. Citric-acid cycle key enzyme activities during in vitro growth and metacyclogenesis of Leishmania infantum promastigotes.

    PubMed

    Louassini, M; Foulquié, M; Benítez, R; Adroher, J

    1999-08-01

    The activities of 5 key regulatory enzymes in most energetic systems, namely citrate synthase (EC 4.1.3.7, CS), NADP-specific isocitrate dehydrogenase (EC 1.1.1.42, ICDH), succinate dehydrogenase (EC 1.3.99.1, SDH), L-malate dehydrogenase (EC 1.1.1.37, MDH), and decarboxylating malic enzyme (EC 1.1.1.40, ME), were measured during the growth and metacyclogenesis of a cutaneous (CL) and a visceral (VL) strain of Leishmania infantum. As occurs with other Leishmania species, infective promastigotes were present along all phases of growth, but their percentages were higher at the early stationary phase for VL and the end of the same phase for CL. High CS and SDH activities were detected in both strains, as compared with other trypanosomatids, bringing more evidence for an actively functional citric-acid cycle in L. infantum. Both strains showed higher levels of CS, ICDH, and MDH and lower SDH and ME activities when more metacyclic promastigotes were present, but in VL these changes paralleled an increase in glucose consumption, whereas in CL these changes coincided with an NH3 hyperproduction. This suggests that the energy metabolism during L. infantum growth and metacyclogenesis is affected by regulated enzymes that probably respond to changes in the culture medium in the levels of glucose and amino acids.

  8. Word-identification priming for ignored and attended words

    NASA Technical Reports Server (NTRS)

    Stone, M.; Ladd, S. L.; Vaidya, C. J.; Gabrieli, J. D.

    1998-01-01

    Three experiments examined contributions of study phase awareness of word identity to subsequent word-identification priming by manipulating visual attention to words at study. In Experiment 1, word-identification priming was reduced for ignored relative to attended words, even though ignored words were identified sufficiently to produce negative priming in the study phase. Word-identification priming was also reduced after color naming relative to emotional valence rating (Experiment 2) or word reading (Experiment 3), even though an effect of emotional valence upon color naming (Experiment 2) indicated that words were identified at study. Thus, word-identification priming was reduced even when word identification occurred at study. Word-identification priming may depend on awareness of word identity at the time of study.

  9. The Last Word

    ERIC Educational Resources Information Center

    McKean, Erin

    2010-01-01

    Go look it up. That is what students who have questions about words are often told. But where should they go? Depending on the question, some resources are better than others, and some are not very good at all, no matter what the question. Finding the most helpful word resource for students can be a challenge, especially now that search engines…

  10. Teaching Word Recognition Skills.

    ERIC Educational Resources Information Center

    Dawson, Mildred A., Comp.

    A series of articles with the chief emphasis on phonics as a means of analyzing words is presented. Various articles pertain to elementary, secondary, and college level instruction. The first of the five parts into which the volume is divided is comprised of a single article which gives an excellent overview of the field of word recognition. Part…

  11. Words That Encourage

    ERIC Educational Resources Information Center

    Eisenbach, Brooke B.

    2014-01-01

    Teachers and education leaders are aware that their words can have a significant effect on their students. Words can build them up and encourage them to work hard or tear them down and lead them to despair. The language used in teacher evaluations is no different, says teacher Brooke Eisenbach. In this article, she shares stories of colleagues…

  12. Words Make for Success.

    ERIC Educational Resources Information Center

    Vernon, Evelyn I.

    Because of the increasing demands that today's society places on language, there is an increasing need for vocabulary building. The opening of new fields, industries, and media and the vocabularies of specialized fields have all contributed to making increased word knowledge a necessity. New words have been coined to describe developments in new…

  13. Occupancy by key transcription factors is a more accurate predictor of enhancer activity than histone modifications or chromatin accessibility

    SciTech Connect

    Dogan, Nergiz; Wu, Weisheng; Morrissey, Christapher S.; Chen, Kuan-Bei; Stonestrom, Aaron; Long, Maria; Keller, Cheryl A.; Cheng, Yong; Jain, Deepti; Visel, Axel; Pennacchio, Len A.; Weiss, Mitchell J.; Blobel, Gerd A.; Hardison, Ross C.

    2015-04-23

    Regulated gene expression controls organismal development, and variation in regulatory patterns has been implicated in complex traits. Thus accurate prediction of enhancers is important for further understanding of these processes. Genome-wide measurement of epigenetic features, such as histone modifications and occupancy by transcription factors, is improving enhancer predictions, but the contribution of these features to prediction accuracy is not known. Given the importance of the hematopoietic transcription factor TAL1 for erythroid gene activation, we predicted candidate enhancers based on genomic occupancy by TAL1 and measured their activity. Contributions of multiple features to enhancer prediction were evaluated based on the results of these and other studies. Results: TAL1-bound DNA segments were active enhancers at a high rate both in transient transfections of cultured cells (39 of 79, or 56%) and transgenic mice (43 of 66, or 65%). The level of binding signal for TAL1 or GATA1 did not help distinguish TAL1-bound DNA segments as active versus inactive enhancers, nor did the density of regulation-related histone modifications. A meta-analysis of results from this and other studies (273 tested predicted enhancers) showed that the presence of TAL1, GATA1, EP300, SMAD1, H3K4 methylation, H3K27ac, and CAGE tags at DNase hypersensitive sites gave the most accurate predictors of enhancer activity, with a success rate over 80% and a median threefold increase in activity. Chromatin accessibility assays and the histone modifications H3K4me1 and H3K27ac were sensitive for finding enhancers, but they have high false positive rates unless transcription factor occupancy is also included. Conclusions: Occupancy by key transcription factors such as TAL1, GATA1, SMAD1, and EP300, along with evidence of transcription, improves the accuracy of enhancer predictions based on epigenetic features.

  14. Occupancy by key transcription factors is a more accurate predictor of enhancer activity than histone modifications or chromatin accessibility

    DOE PAGES

    Dogan, Nergiz; Wu, Weisheng; Morrissey, Christapher S.; ...

    2015-04-23

    Regulated gene expression controls organismal development, and variation in regulatory patterns has been implicated in complex traits. Thus accurate prediction of enhancers is important for further understanding of these processes. Genome-wide measurement of epigenetic features, such as histone modifications and occupancy by transcription factors, is improving enhancer predictions, but the contribution of these features to prediction accuracy is not known. Given the importance of the hematopoietic transcription factor TAL1 for erythroid gene activation, we predicted candidate enhancers based on genomic occupancy by TAL1 and measured their activity. Contributions of multiple features to enhancer prediction were evaluated based on the resultsmore » of these and other studies. Results: TAL1-bound DNA segments were active enhancers at a high rate both in transient transfections of cultured cells (39 of 79, or 56%) and transgenic mice (43 of 66, or 65%). The level of binding signal for TAL1 or GATA1 did not help distinguish TAL1-bound DNA segments as active versus inactive enhancers, nor did the density of regulation-related histone modifications. A meta-analysis of results from this and other studies (273 tested predicted enhancers) showed that the presence of TAL1, GATA1, EP300, SMAD1, H3K4 methylation, H3K27ac, and CAGE tags at DNase hypersensitive sites gave the most accurate predictors of enhancer activity, with a success rate over 80% and a median threefold increase in activity. Chromatin accessibility assays and the histone modifications H3K4me1 and H3K27ac were sensitive for finding enhancers, but they have high false positive rates unless transcription factor occupancy is also included. Conclusions: Occupancy by key transcription factors such as TAL1, GATA1, SMAD1, and EP300, along with evidence of transcription, improves the accuracy of enhancer predictions based on epigenetic features.« less

  15. Spaceflight and simulated microgravity cause a significant reduction of key gene expression in early T-cell activation.

    PubMed

    Martinez, Emily M; Yoshida, Miya C; Candelario, Tara Lynne T; Hughes-Fulford, Millie

    2015-03-15

    Healthy immune function depends on precise regulation of lymphocyte activation. During the National Aeronautics and Space Administration (NASA) Apollo and Shuttle eras, multiple spaceflight studies showed depressed lymphocyte activity under microgravity (μg) conditions. Scientists on the ground use two models of simulated μg (sμg): 1) the rotating wall vessel (RWV) and 2) the random positioning machine (RPM), to study the effects of altered gravity on cell function before advancing research to the true μg when spaceflight opportunities become available on the International Space Station (ISS). The objective of this study is to compare the effects of true μg and sμg on the expression of key early T-cell activation genes in mouse splenocytes from spaceflight and ground animals. For the first time, we compared all three conditions of microgravity spaceflight, RPM, and RWV during immune gene activation of Il2, Il2rα, Ifnγ, and Tagap; moreover, we confirm two new early T-cell activation genes, Iigp1 and Slamf1. Gene expression for all samples was analyzed using quantitative real-time PCR (qRT-PCR). Our results demonstrate significantly increased gene expression in activated ground samples with suppression of mouse immune function in spaceflight, RPM, and RWV samples. These findings indicate that sμg models provide an excellent test bed for scientists to develop baseline studies and augment true μg in spaceflight experiments. Ultimately, sμg and spaceflight studies in lymphocytes may provide insight into novel regulatory pathways, benefiting both future astronauts and those here on earth suffering from immune disorders.

  16. Spaceflight and simulated microgravity cause a significant reduction of key gene expression in early T-cell activation

    PubMed Central

    Martinez, Emily M.; Yoshida, Miya C.; Candelario, Tara Lynne T.

    2015-01-01

    Healthy immune function depends on precise regulation of lymphocyte activation. During the National Aeronautics and Space Administration (NASA) Apollo and Shuttle eras, multiple spaceflight studies showed depressed lymphocyte activity under microgravity (μg) conditions. Scientists on the ground use two models of simulated μg (sμg): 1) the rotating wall vessel (RWV) and 2) the random positioning machine (RPM), to study the effects of altered gravity on cell function before advancing research to the true μg when spaceflight opportunities become available on the International Space Station (ISS). The objective of this study is to compare the effects of true μg and sμg on the expression of key early T-cell activation genes in mouse splenocytes from spaceflight and ground animals. For the first time, we compared all three conditions of microgravity spaceflight, RPM, and RWV during immune gene activation of Il2, Il2rα, Ifnγ, and Tagap; moreover, we confirm two new early T-cell activation genes, Iigp1 and Slamf1. Gene expression for all samples was analyzed using quantitative real-time PCR (qRT-PCR). Our results demonstrate significantly increased gene expression in activated ground samples with suppression of mouse immune function in spaceflight, RPM, and RWV samples. These findings indicate that sμg models provide an excellent test bed for scientists to develop baseline studies and augment true μg in spaceflight experiments. Ultimately, sμg and spaceflight studies in lymphocytes may provide insight into novel regulatory pathways, benefiting both future astronauts and those here on earth suffering from immune disorders. PMID:25568077

  17. Near-instant automatic access to visually presented words in the human neocortex: neuromagnetic evidence.

    PubMed

    Shtyrov, Yury; MacGregor, Lucy J

    2016-05-24

    Rapid and efficient processing of external information by the brain is vital to survival in a highly dynamic environment. The key channel humans use to exchange information is language, but the neural underpinnings of its processing are still not fully understood. We investigated the spatio-temporal dynamics of neural access to word representations in the brain by scrutinising the brain's activity elicited in response to psycholinguistically, visually and phonologically matched groups of familiar words and meaningless pseudowords. Stimuli were briefly presented on the visual-field periphery to experimental participants whose attention was occupied with a non-linguistic visual feature-detection task. The neural activation elicited by these unattended orthographic stimuli was recorded using multi-channel whole-head magnetoencephalography, and the timecourse of lexically-specific neuromagnetic responses was assessed in sensor space as well as at the level of cortical sources, estimated using individual MR-based distributed source reconstruction. Our results demonstrate a neocortical signature of automatic near-instant access to word representations in the brain: activity in the perisylvian language network characterised by specific activation enhancement for familiar words, starting as early as ~70 ms after the onset of unattended word stimuli and underpinned by temporal and inferior-frontal cortices.

  18. Near-instant automatic access to visually presented words in the human neocortex: neuromagnetic evidence

    PubMed Central

    Shtyrov, Yury; MacGregor, Lucy J.

    2016-01-01

    Rapid and efficient processing of external information by the brain is vital to survival in a highly dynamic environment. The key channel humans use to exchange information is language, but the neural underpinnings of its processing are still not fully understood. We investigated the spatio-temporal dynamics of neural access to word representations in the brain by scrutinising the brain’s activity elicited in response to psycholinguistically, visually and phonologically matched groups of familiar words and meaningless pseudowords. Stimuli were briefly presented on the visual-field periphery to experimental participants whose attention was occupied with a non-linguistic visual feature-detection task. The neural activation elicited by these unattended orthographic stimuli was recorded using multi-channel whole-head magnetoencephalography, and the timecourse of lexically-specific neuromagnetic responses was assessed in sensor space as well as at the level of cortical sources, estimated using individual MR-based distributed source reconstruction. Our results demonstrate a neocortical signature of automatic near-instant access to word representations in the brain: activity in the perisylvian language network characterised by specific activation enhancement for familiar words, starting as early as ~70 ms after the onset of unattended word stimuli and underpinned by temporal and inferior-frontal cortices. PMID:27217080

  19. The SEDIBUD (Sediment Budgets in Cold Environments) Programme: Ongoing activities and selected key tasks for the coming years

    NASA Astrophysics Data System (ADS)

    Beylich, Achim A.; Lamoureux, Scott F.; Decaulne, Armelle

    2012-09-01

    Projected climate change in cold environments is expected to alter melt-season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. In addition, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active layer depths. The combined effects of these changes will alter surface environments in cold climate regions and change the fluxes of sediments, nutrients and solutes, but the absence of data, coordinated process monitoring and coordinated quantitative analysis to understand the sensitivity of the Earth surface environment are acute in cold climate environments. The International Association of Geomorphologists (I.A.G./A.I.G.) SEDIBUD (Sediment Budgets in Cold Environments) Programme has been formed to address this key knowledge gap and builds on the earlier European Science Foundation (ESF) SEDIFLUX (Sedimentary Source-to-Sink-Fluxes in Cold Environments) Network. Coordinated efforts are carried out to monitor, quantify, compare and model sedimentary fluxes and possible effects of predicted climate change in currently 44 selected SEDIBUD Key Test Sites (cold climate environment catchments) worldwide.

  20. Disrupting a key hydrophobic pair in the oligomerization interface of the actinoporins impairs their pore-forming activity.

    PubMed

    Mesa-Galloso, Haydeé; Delgado-Magnero, Karelia H; Cabezas, Sheila; López-Castilla, Aracelys; Hernández-González, Jorge E; Pedrera, Lohans; Alvarez, Carlos; Peter Tieleman, D; García-Sáez, Ana J; Lanio, Maria E; Ros, Uris; Valiente, Pedro A

    2017-03-01

    Crystallographic data of the dimeric and octameric forms of fragaceatoxin C (FraC) suggested the key role of a small hydrophobic protein-protein interaction surface for actinoporins oligomerization and pore formation in membranes. However, site-directed mutagenesis studies supporting this hypothesis for others actinoporins are still lacking. Here, we demonstrate that disrupting the key hydrophobic interaction between V60 and F163 (FraC numbering scheme) in the oligomerization interface of FraC, equinatoxin II (EqtII), and sticholysin II (StII) impairs the pore formation activity of these proteins. Our results allow for the extension of the importance of FraC protein-protein interactions in the stabilization of the oligomeric intermediates of StII and EqtII pointing out that all of these proteins follow a similar pathway of membrane disruption. These findings support the hybrid pore proposal as the universal model of actinoporins pore formation. Moreover, we reinforce the relevance of dimer formation, which appears to be a functional intermediate in the assembly pathway of some different pore-forming proteins.

  1. Variation in key genes of serotonin and norepinephrine function predicts gamma-band activity during goal-directed attention.

    PubMed

    Enge, Sören; Fleischhauer, Monika; Lesch, Klaus-Peter; Reif, Andreas; Strobel, Alexander

    2014-05-01

    Recent evidence shows that genetic variations in key regulators of serotonergic (5-HT) signaling explain variance in executive tasks, which suggests modulatory actions of 5-HT on goal-directed selective attention as one possible underlying mechanism. To investigate this link, 130 volunteers were genotyped for the 5-HT transporter gene-linked polymorphic region (5-HTTLPR) and for a variation (TPH2-703 G/T) of the TPH2 gene coding for the rate-limiting enzyme of 5-HT synthesis in the brain. Additionally, a functional polymorphism of the norepinephrine transporter gene (NET -3081 A/T) was considered, which was recently found to predict attention and working memory processes in interaction with serotonergic genes. The flanker-based Attention Network Test was used to assess goal-directed attention and the efficiency of attentional networks. Event-related gamma-band activity served to indicate selective attention at the intermediate phenotype level. The main findings were that 5-HTTLPR s allele and TPH2 G-allele homozygotes showed increased induced gamma-band activity during target processing when combined with the NET A/A genotype compared with other genotype combinations, and that gamma activity mediates the genotype-specific effects on task performance. The results further support a modulatory role of 5-HT and NE function in the top-down attentional selection of motivationally relevant over competing or irrelevant sensory input.

  2. Key Issues in the Role of Peroxisome Proliferator–Activated Receptor Agonism and Cell Signaling in Trichloroethylene Toxicity

    PubMed Central

    Keshava, Nagalakshmi; Caldwell, Jane C.

    2006-01-01

    Peroxisome proliferator–activated receptor α (PPARα) is thought to be involved in several different diseases, toxic responses, and receptor pathways. The U.S. Environmental Protection Agency 2001 draft trichloroethylene (TCE) risk assessment concluded that although PPAR may play a role in liver tumor induction, the role of its activation and the sequence of subsequent events important to tumorigenesis are not well defined, particularly because of uncertainties concerning the extraperoxisomal effects. In this article, which is part of a mini-monograph on key issues in the health risk assessment of TCE, we summarize some of the scientific literature published since that time on the effects and actions of PPARα that help inform and illustrate the key scientific questions relevant to TCE risk assessment. Recent analyses of the role of PPARα in gene expression changes caused by TCE and its metabolites provide only limited data for comparison with other PPARα agonists, particularly given the difficulties in interpreting results involving PPARα knockout mice. Moreover, the increase in data over the last 5 years from the broader literature on PPARα agonists presents a more complex array of extraperoxisomal effects and actions, suggesting the possibility that PPARα may be involved in modes of action (MOAs) not only for liver tumors but also for other effects of TCE and its metabolites. In summary, recent studies support the conclusion that determinations of the human relevance and susceptibility to PPARα-related MOA(s) of TCE-induced effects cannot rely on inferences regarding peroxisome proliferation per se and require a better understanding of the interplay of extraperoxisomal events after PPARα agonism. PMID:16966106

  3. Probing the catalytic mechanism of bovine CD38/NAD+ glycohydrolase by site directed mutagenesis of key active site residues.

    PubMed

    Kuhn, Isabelle; Kellenberger, Esther; Cakir-Kiefer, Céline; Muller-Steffner, Hélène; Schuber, Francis

    2014-07-01

    Bovine CD38/NAD(+) glycohydrolase catalyzes the hydrolysis of NAD(+) to nicotinamide and ADP-ribose and the formation of cyclic ADP-ribose via a stepwise reaction mechanism. Our recent crystallographic study of its Michaelis complex and covalently-trapped intermediates provided insights into the modalities of substrate binding and the molecular mechanism of bCD38. The aim of the present work was to determine the precise role of key conserved active site residues (Trp118, Glu138, Asp147, Trp181 and Glu218) by focusing mainly on the cleavage of the nicotinamide-ribosyl bond. We analyzed the kinetic parameters of mutants of these residues which reside within the bCD38 subdomain in the vicinity of the scissile bond of bound NAD(+). To address the reaction mechanism we also performed chemical rescue experiments with neutral (methanol) and ionic (azide, formate) nucleophiles. The crucial role of Glu218, which orients the substrate for cleavage by interacting with the N-ribosyl 2'-OH group of NAD(+), was highlighted. This contribution to catalysis accounts for almost half of the reaction energy barrier. Other contributions can be ascribed notably to Glu138 and Asp147 via ground-state destabilization and desolvation in the vicinity of the scissile bond. Key interactions with Trp118 and Trp181 were also proven to stabilize the ribooxocarbenium ion-like transition state. Altogether we propose that, as an alternative to a covalent acylal reaction intermediate with Glu218, catalysis by bCD38 proceeds through the formation of a discrete and transient ribooxocarbenium intermediate which is stabilized within the active site mostly by electrostatic interactions.

  4. Generalization of word meanings during infant sleep.

    PubMed

    Friedrich, Manuela; Wilhelm, Ines; Born, Jan; Friederici, Angela D

    2015-01-29

    Sleep consolidates memory and promotes generalization in adults, but it is still unknown to what extent the rapidly growing infant memory benefits from sleep. Here we show that during sleep the infant brain reorganizes recent memories and creates semantic knowledge from individual episodic experiences. Infants aged between 9 and 16 months were given the opportunity to encode both objects as specific word meanings and categories as general word meanings. Event-related potentials indicate that, initially, infants acquire only the specific but not the general word meanings. About 1.5 h later, infants who napped during the retention period, but not infants who stayed awake, remember the specific word meanings and, moreover, successfully generalize words to novel category exemplars. Independently of age, the semantic generalization effect is correlated with sleep spindle activity during the nap, suggesting that sleep spindles are involved in infant sleep-dependent brain plasticity.

  5. Modelling the Effects of Semantic Ambiguity in Word Recognition

    ERIC Educational Resources Information Center

    Rodd, Jennifer M.; Gaskell, M. Gareth; Marslen-Wilson, William D.

    2004-01-01

    Most words in English are ambiguous between different interpretations; words can mean different things in different contexts. We investigate the implications of different types of semantic ambiguity for connectionist models of word recognition. We present a model in which there is competition to activate distributed semantic representations. The…

  6. THE ENGLISH WORD SPECULUM. VOLUME I. THE RANDOM WORD LIST,

    DTIC Science & Technology

    The English Word Speculum is a series of volumes illustrating the structural properties of written English words . The collection is intended to be...used as a complement to the standard dictionaries of English words , and should be of particular value to linguists and students of English. The word ...list used to generate the volumes consists of left-justified, bold-face words contained in the Shorter Oxford English Dictionary, a total of 73,582 words

  7. The English Word Speculum. Volume iii. The Reverse Word List,

    DTIC Science & Technology

    The English Word Speculum is a series of volumes illustrating the structural properties of written English words . The collection is intended to be...used as a complement to the standard dictionaries of English words , and should be of particular value to linguists and students of English. The word ...list used to generate the volumes consists of left-justified, bold-face words contained in the Shorter Oxford English Dictionary, a total of 73,582 words

  8. Word Processing differences between dyslexic and control children

    PubMed Central

    Paul, Isabella; Bott, Christof; Wienbruch, Christian; Elbert, Thomas R

    2006-01-01

    Background The aim of this study was to investigate brain responses triggered by different wordclasses in dyslexic and control children. The majority of dyslexic children have difficulties to phonologically assemble a word from sublexical parts following grapheme-to-phoneme correspondences. Therefore, we hypothesised that dyslexic children should mainly differ from controls processing low frequent words that are unfamiliar to the reader. Methods We presented different wordclasses (high and low frequent words, pseudowords) in a rapid serial visual word (RSVP) design and performed wavelet analysis on the evoked activity. Results Dyslexic children had lower evoked power amplitudes and a higher spectral frequency for low frequent words compared to control children. No group differences were found for high frequent words and pseudowords. Control children had higher evoked power amplitudes and a lower spectral frequency for low frequent words compared to high frequent words and pseudowords. This pattern was not present in the dyslexic group. Conclusion Dyslexic children differed from control children only in their brain responses to low frequent words while showing no modulated brain activity in response to the three word types. This might support the hypothesis that dyslexic children are selectively impaired reading words that require sublexical processing. However, the lacking differences between word types raise the question if dyslexic children were able to process the words presented in rapid serial fashion in an adequate way. Therefore the present results should only be interpreted as evidence for a specific sublexical processing deficit with caution. PMID:16441886

  9. Screening active components from Yu-ping-feng-san for regulating initiative key factors in allergic sensitization.

    PubMed

    Shen, Dandan; Xie, Xuejian; Zhu, Zhijie; Yu, Xi; Liu, Hailiang; Wang, Huizhu; Fan, Hongwei; Wang, Dawei; Jiang, Guorong; Hong, Min

    2014-01-01

    Yu-ping-feng-san (YPFS) is a Chinese medical formula that is used clinically for allergic diseases and characterized by reducing allergy relapse. Our previous studies demonstrated that YPFS efficiently inhibited T helper 2 cytokines in allergic inflammation. The underlying mechanisms of action of YPFS and its effective components remain unclear. In this study, it was shown that YPFS significantly inhibited production of thymic stromal lymphopoietin (TSLP), an epithelial cell-derived initiative factor in allergic inflammation, in vitro and in vivo. A method of human bronchial epithelial cell (16HBE) binding combined with HPLC-MS (named 16HBE-HPLC-MS) was established to explore potential active components of YPFS. The following five components bound to 16HBE cells: calycosin-7-glucoside, ononin, claycosin, sec-o-glucosylhamaudol and formononetin. Serum from YPFS-treated mice was analyzed and three major components were detected claycosin, formononetin and cimifugin. Among these, claycosin and formononetin were detected by 16HBE-HPLC-MS and in the serum of YPFS-treated mice. Claycosin and formononetin decreased the level of TSLP markedly at the initial stage of allergic inflammation in vivo. Nuclear factor (NF)-κB, a key transcription factor in TSLP production, was also inhibited by claycosin and formononetin, either in terms of transcriptional activation or its nuclear translocation in vitro. Allergic inflammation was reduced by claycosin and formononetin when they are administered only at the initial stage in a murine model of atopic contact dermatitis. Thus, epithelial cell binding combined with HPLC-MS is a valid method for screening active components from complex mixtures of Chinese medicine. It was demonstrated that the compounds screened from YPFS significantly attenuated allergic inflammation probably by reducing TSLP production via regulating NF-κB activation.

  10. AMP-activated kinase in human spermatozoa: identification, intracellular localization, and key function in the regulation of sperm motility.

    PubMed

    Calle-Guisado, Violeta; de Llera, Ana Hurtado; Martin-Hidalgo, David; Mijares, Jose; Gil, Maria C; Alvarez, Ignacio S; Bragado, Maria J; Garcia-Marin, Luis J

    2016-09-27

    AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This work's aims are AMPK identification, intracellular localization, and their role in human spermatozoa function. Semen was obtained from healthy human donors. Sperm AMPK and phospho-Thr172-AMPK were analyzed by Western blotting and indirect immunofluorescence. High- and low-quality sperm populations were separated by a 40%-80% density gradient. Human spermatozoa motility was evaluated by an Integrated Semen Analysis System (ISAS) in the presence or absence of the AMPK inhibitor compound C (CC). AMPK is localized along the human spermatozoa, at the entire acrosome, midpiece and tail with variable intensity, whereas its active form, phospho-Thr172-AMPK, shows a prominent staining at the acrosome and sperm tail with a weaker staining in the midpiece and the postacrosomal region. Interestingly, spermatozoa bearing an excess residual cytoplasm show strong AMPK staining in this subcellular compartment. Both AMPK and phospho-Thr172-AMPK human spermatozoa contents exhibit important individual variations. Moreover, active AMPK is predominant in the high motility sperm population, where shows a stronger intensity compared with the low motility sperm population. Inhibition of AMPK activity in human spermatozoa by CC treatment leads to a significant reduction in any sperm motility parameter analyzed: percent of motile sperm, sperm velocities, progressivity, and other motility coefficients. This work identifies and points out AMPK as a new molecular mechanism involved in human spermatozoa motility. Further AMPK implications in the clinical efficiency of assisted reproduction and in other reproductive areas need to be studied.

  11. THE ENGLISH WORD SPECULUM. VOLUME II. THE FORWARD WORD LIST,

    DTIC Science & Technology

    The Forward Word List consists of the 66,439 ’regular’ words that occur in the Shorter Oxford. The list is grouped, first, according to the entry in...the vowel-stringcount column. Thus, the first set of words , coded A, is a collection of all regular words from the Shorter Oxford that contain an...apostrophe in the word field. These are followed by the broken (B) words , the hyphenated (H) words , and then all words having a numberical value in the

  12. Word Processing: The Air Force Administrators’ Handbook

    DTIC Science & Technology

    1979-05-01

    LEYEL > WORD PROCESSING ERRORCOP Qis 4 pL THE? ~ AIR FORCE ADMINISTRATOR$.! ’--s..HANDBOOK 400 Zi LUPRED F~ Fiir [rLT The views and opinions...INSTRUCTIONSBEFORE COMPLETING FORM I. REPORT NUMBER .O.Vk Er.;. NO. R CIPIENT’S CATALOG NUMBER 4. TITLE (and Subtitle) S. ’TYPE OF REPORT & PERIOD COVERED WORD ...Accession No. ADB 040882 L 19. KEY WORDS (Continue on reverse aide it necessary and identify by block number) Administration / / Administrative Systems

  13. Mapping of transcription factor motifs in active chromatin identifies IRF5 as key regulator in classical Hodgkin lymphoma

    PubMed Central

    Kreher, Stephan; Bouhlel, M. Amine; Cauchy, Pierre; Lamprecht, Björn; Li, Shuang; Grau, Michael; Hummel, Franziska; Köchert, Karl; Anagnostopoulos, Ioannis; Jöhrens, Korinna; Hummel, Michael; Hiscott, John; Wenzel, Sören-Sebastian; Lenz, Peter; Schneider, Markus; Küppers, Ralf; Scheidereit, Claus; Giefing, Maciej; Siebert, Reiner; Rajewsky, Klaus; Lenz, Georg; Cockerill, Peter N.; Janz, Martin; Dörken, Bernd; Bonifer, Constanze; Mathas, Stephan

    2014-01-01

    Deregulated transcription factor (TF) activities are commonly observed in hematopoietic malignancies. Understanding tumorigenesis therefore requires determining the function and hierarchical role of individual TFs. To identify TFs central to lymphomagenesis, we identified lymphoma type-specific accessible chromatin by global mapping of DNaseI hypersensitive sites and analyzed enriched TF-binding motifs in these regions. Applying this unbiased approach to classical Hodgkin lymphoma (HL), a common B-cell–derived lymphoma with a complex pattern of deregulated TFs, we discovered interferon regulatory factor (IRF) sites among the top enriched motifs. High-level expression of the proinflammatory TF IRF5 was specific to HL cells and crucial for their survival. Furthermore, IRF5 initiated a regulatory cascade in human non-Hodgkin B-cell lines and primary murine B cells by inducing the TF AP-1 and cooperating with NF-κB to activate essential characteristic features of HL. Our strategy efficiently identified a lymphoma type-specific key regulator and uncovered a tumor promoting role of IRF5. PMID:25288773

  14. Active Pin1 is a key target of all-trans retinoic acid in acute promyelocytic leukemia and breast cancer

    PubMed Central

    Wei, Shuo; Kozono, Shingo; Kats, Lev; Nechama, Morris; Li, Wenzong; Guarnerio, Jlenia; Luo, Manli; You, Mi-Hyeon; Yao, Yandan; Kondo, Asami; Hu, Hai; Bozkurt, Gunes; Moerke, Nathan J.; Cao, Shugeng; Reschke, Markus; Chen, Chun-Hau; Rego, Eduardo M.; LoCoco, Francesco; Cantley, Lewis; Lee, Tae Ho; Wu, Hao; Zhang, Yan; Pandolfi, Pier Paolo; Zhou, Xiao Zhen; Lu, Kun Ping

    2015-01-01

    A common key regulator of oncogenic signaling pathways in multiple tumor types is the unique isomerase Pin1. However, available Pin1 inhibitors lack the required specificity and potency. Using mechanism-based screening, here we find that all-trans retinoic acid (ATRA)--a therapy for acute promyelocytic leukemia (APL) that is considered the first example of targeted therapy in cancer, but its drug target remains elusive--inhibits and degrades active Pin1 selectively in cancer cells by directly binding to the substrate phosphate- and proline-binding pockets in the Pin1 active site. ATRA-induced Pin1 ablation degrades the fusion oncogene PML-RARα and treats APL in cell and animal models and human patients. ATRA-induced Pin1 ablation also inhibits triple negative breast cancer cell growth in human cells and in animal models by acting on many Pin1 substrate oncogenes and tumor suppressors. Thus, ATRA simultaneously blocks multiple Pin1-regulated cancer-driving pathways, an attractive property for treating aggressive and drug-resistant tumors. PMID:25849135

  15. Mapping of transcription factor motifs in active chromatin identifies IRF5 as key regulator in classical Hodgkin lymphoma.

    PubMed

    Kreher, Stephan; Bouhlel, M Amine; Cauchy, Pierre; Lamprecht, Björn; Li, Shuang; Grau, Michael; Hummel, Franziska; Köchert, Karl; Anagnostopoulos, Ioannis; Jöhrens, Korinna; Hummel, Michael; Hiscott, John; Wenzel, Sören-Sebastian; Lenz, Peter; Schneider, Markus; Küppers, Ralf; Scheidereit, Claus; Giefing, Maciej; Siebert, Reiner; Rajewsky, Klaus; Lenz, Georg; Cockerill, Peter N; Janz, Martin; Dörken, Bernd; Bonifer, Constanze; Mathas, Stephan

    2014-10-21

    Deregulated transcription factor (TF) activities are commonly observed in hematopoietic malignancies. Understanding tumorigenesis therefore requires determining the function and hierarchical role of individual TFs. To identify TFs central to lymphomagenesis, we identified lymphoma type-specific accessible chromatin by global mapping of DNaseI hypersensitive sites and analyzed enriched TF-binding motifs in these regions. Applying this unbiased approach to classical Hodgkin lymphoma (HL), a common B-cell-derived lymphoma with a complex pattern of deregulated TFs, we discovered interferon regulatory factor (IRF) sites among the top enriched motifs. High-level expression of the proinflammatory TF IRF5 was specific to HL cells and crucial for their survival. Furthermore, IRF5 initiated a regulatory cascade in human non-Hodgkin B-cell lines and primary murine B cells by inducing the TF AP-1 and cooperating with NF-κB to activate essential characteristic features of HL. Our strategy efficiently identified a lymphoma type-specific key regulator and uncovered a tumor promoting role of IRF5.

  16. Development of radiometric assays for quantification of enzyme activities of the key enzymes of thyroid hormones metabolism.

    PubMed

    Pavelka, S

    2014-01-01

    We newly elaborated and adapted several radiometric enzyme assays for the determination of activities of the key enzymes engaged in the biosynthesis (thyroid peroxidase, TPO) and metabolic transformations (conjugating enzymes and iodothyronine deiodinases, IDs) of thyroid hormones (THs) in the thyroid gland and in peripheral tissues, especially in white adipose tissue (WAT). We also elaborated novel, reliable radiometric methods for extremely sensitive determination of enzyme activities of IDs of types 1, 2 and 3 in microsomal fractions of different rat and human tissues, as well as in homogenates of cultured mammalian cells. The use of optimized TLC separation of radioactive products from the unconsumed substrates and film-less autoradiography of radiochromatograms, taking advantage of storage phosphor screens, enabled us to determine IDs enzyme activities as low as 10(-18) katals. In studies of the interaction of fluoxetine (Fluox) with the metabolism of THs, we applied adapted radiometric enzyme assays for iodothyronine sulfotransferases (ST) and uridine 5'-diphospho-glucuronyltransferase (UDP-GT). Fluox is the most frequently used representative of a new group of non-tricyclic antidepressant drugs--selective serotonin re-uptake inhibitors. We used the elaborated assays for quantification the effects of Fluox and for the assessment of the degree of potential induction of rat liver ST and/or UDP-GT enzyme activities by Fluox alone or in combination with T(3). Furthermore, we studied possible changes in IDs activities in murine adipose tissue under the conditions that promoted either tissue hypertrophy (obesogenic treatment) or involution (caloric restriction), and in response to leptin, using our newly developed radiometric enzyme assays for IDs. Our results suggest that deiodinase D1 has a functional role in WAT, with D1 possibly being involved in the control of adipose tissue metabolism and/or accumulation of the tissue. Significant positive correlation between

  17. Comprehension Before Word Identification

    ERIC Educational Resources Information Center

    Garman, Dorothy

    1977-01-01

    Examines Frank Smith's analysis of the reading process with respect to comprehension, specifically, his assertion that during the reading process, comprehension of meaning precedes word identification. Discusses the implications of Smith's analysis for the teaching of reading. (JM)

  18. Word Problems Made Painless.

    ERIC Educational Resources Information Center

    Noddings, Nel

    1980-01-01

    Computer assisted instruction is presented as a tool for helping students learn to successfully solve word problems. Four stages of developing a curriculum for elementary school mathematics, grades three through six, are covered. (MP)

  19. Images/Words.

    ERIC Educational Resources Information Center

    MacDonald, Martin

    1992-01-01

    Maintains that words come from strongly felt images. Contrasts the stark language environment of the author's first school years with his vivid memories of stories and poetry in his grandparents', parents', and his own house. (SR)

  20. Neural correlates of merging number words.

    PubMed

    Hung, Yi-Hui; Pallier, Christophe; Dehaene, Stanislas; Lin, Yi-Chen; Chang, Acer; Tzeng, Ovid J-L; Wu, Denise H

    2015-11-15

    Complex number words (e.g., "twenty two") are formed by merging together several simple number words (e.g., "twenty" and "two"). In the present study, we explored the neural correlates of this operation and investigated to what extent it engages brain areas involved processing numerical quantity and linguistic syntactic structure. Participants speaking two typologically distinct languages, French and Chinese, were required to read aloud sequences of simple number words while their cerebral activity was recorded by functional magnetic resonance imaging. Each number word could either be merged with the previous ones (e.g., 'twenty three') or not (e.g., 'three twenty'), thus forming four levels ranging from lists of number words to complex numerals. When a number word could be merged with the preceding ones, it was named faster than when it could not. Neuroimaging results showed that the number of merges correlated with activation in the left inferior frontal gyrus and in the left inferior parietal lobule. Consistent findings across Chinese and French participants suggest that these regions serve as the neural bases for forming complex number words in different languages.

  1. Automatic semantic feedback during visual word recognition.

    PubMed

    Reimer, Jason F; Lorsbach, Thomas C; Bleakney, Dana M

    2008-04-01

    Four experiments were conducted to determine whether semantic feedback spreads to orthographic and/or phonological representations during visual word recognition and whether such feedback occurs automatically. Three types of prime-target word pairs were used within the mediated-priming paradigm: (1) homophonically mediated (e.g.,frog-[toad]-towed), (2) orthographically mediated (e.g.,frog-[toad]-told), and (3) associatively related (e.g.,frog-toad). Using both brief (53 msec; Experiment 1) and long (413 msec; Experiment 3) prime exposure durations, significant facilitatory-priming effects were found in the response time data with orthographically, but not homophonically, mediated prime-target word pairs. When the prime exposure duration was shortened to 33 msec in Experiment 4, however, facilitatory priming was absent with both orthographically and homophonically mediated word pairs. In addition, with a brief (53-msec) prime exposure duration, direct-priming effects were found with associatively (e.g.,frog-toad), orthographically (e.g., toad-told), and homophonically (e.g., toad-towed) related word pairs in Experiment 2. Taken together, these results indicate that following the initial activation of semantic representations, activation automatically feeds back to orthographic, but not phonological, representations during the early stages of word processing. These findings were discussed in the context of current accounts of visual word recognition.

  2. Developing WordSmith

    ERIC Educational Resources Information Center

    Scott, Mike

    2008-01-01

    WordSmith Tools, since its launch in 1996, has had a rather unusual history and the aim of this paper is to record some of the chief influences on its development. The paper thus presents and discusses the history of WordSmith Tools and its predecessors going back to the early 1980s when processors were much slower, memory very limited and disk…

  3. Acidosis is a key regulator of osteoblast ecto-nucleotidase pyrophosphatase/phosphodiesterase 1 (NPP1) expression and activity.

    PubMed

    Orriss, Isabel R; Key, Michelle L; Hajjawi, Mark O R; Millán, José L; Arnett, Timothy R

    2015-12-01

    Previous work has shown that acidosis prevents bone nodule formation by osteoblasts in vitro by inhibiting mineralisation of the collagenous matrix. The ratio of phosphate (Pi ) to pyrophosphate (PPi ) in the bone microenvironment is a fundamental regulator of bone mineralisation. Both Pi and PPi , a potent inhibitor of mineralisation, are generated from extracellular nucleotides by the actions of ecto-nucleotidases. This study investigated the expression and activity of ecto-nucleotidases by osteoblasts under normal and acid conditions. We found that osteoblasts express mRNA for a number of ecto-nucleotidases including NTPdase 1-6 (ecto-nucleoside triphosphate diphosphohydrolase) and NPP1-3 (ecto-nucleotide pyrophosphatase/phosphodiesterase). The rank order of mRNA expression in differentiating rat osteoblasts (day 7) was Enpp1 > NTPdase 4 > NTPdase 6 > NTPdase 5 >  alkaline phosphatase > ecto-5-nucleotidase > Enpp3 > NTPdase 1 > NTPdase 3 > Enpp2 > NTPdase 2. Acidosis (pH 6.9) upregulated NPP1 mRNA (2.8-fold) and protein expression at all stages of osteoblast differentiation compared to physiological pH (pH 7.4); expression of other ecto-nucleotidases was unaffected. Furthermore, total NPP activity was increased up to 53% in osteoblasts cultured in acid conditions (P < 0.001). Release of ATP, one of the key substrates for NPP1, from osteoblasts, was unaffected by acidosis. Further studies showed that mineralised bone formation by osteoblasts cultured from NPP1 knockout mice was increased compared with wildtypes (2.5-fold, P < 0.001) and was partially resistant to the inhibitory effect of acidosis. These results indicate that increased NPP1 expression and activity might contribute to the decreased mineralisation observed when osteoblasts are exposed to acid conditions.

  4. The Uncertainty of Word Meanings Found in Nursery Rhyme Vocabulary.

    ERIC Educational Resources Information Center

    Gruss, Linda C.

    A study examined how many of 11 key words in 4 famous Mother Goose nursery rhymes were understood by parents of first graders. The first questionnaire (designed to determine if context clues were helpful in deciphering what words meant) was returned by 37 parents in an urban school district and by 49 parents in a suburban school district. The…

  5. Flagellin acting via TLR5 is the major activator of key signaling pathways leading to NF-κB and proinflammatory gene program activation in intestinal epithelial cells

    PubMed Central

    Tallant, Thomas; Deb, Amitabha; Kar, Niladri; Lupica, Joseph; de Veer, Michael J; DiDonato, Joseph A

    2004-01-01

    Background Infection of intestinal epithelial cells by pathogenic Salmonella leads to activation of signaling cascades that ultimately initiate the proinflammatory gene program. The transcription factor NF-κB is a key regulator/activator of this gene program and is potently activated. We explored the mechanism by which Salmonella activates NF-κB during infection of cultured intestinal epithelial cells and found that flagellin produced by the bacteria and contained on them leads to NF-κB activation in all the cells; invasion of cells by the bacteria is not required to activate NF-κB. Results Purified flagellin activated the mitogen activated protein kinase (MAPK), stress-activated protein kinase (SAPK) and Ikappa B kinase (IKK) signaling pathways that lead to expression of the proinflammatory gene program in a temporal fashion nearly identical to that of infection of intestinal epithelial cells by Salmonella. Flagellin expression was required for Salmonella invasion of host cells and it activated NF-κB via toll-like receptor 5 (TLR5). Surprisingly, a number of cell lines found to be unresponsive to flagellin express TLR5 and expression of exogenous TLR5 in these cells induces NF-κB activity in response to flagellin challenge although not robustly. Conversely, overexpression of dominant-negative TLR5 alleles only partially blocks NF-κB activation by flagellin. These observations are consistent with the possibility of either a very stable TLR5 signaling complex, the existence of a low abundance flagellin co-receptor or required adapter, or both. Conclusion These collective results provide the evidence that flagellin acts as the main determinant of Salmonella mediated NF-κB and proinflammatory signaling and gene activation by this flagellated pathogen. In addition, expression of the fli C gene appears to play an important role in the proper functioning of the TTSS since mutants that fail to express fli C are defective in expressing a subset of Sip proteins and

  6. Lexical control of within-word eye movements.

    PubMed

    Pynte, J

    1996-08-01

    Eye movements were recorded during the reading of long words, which were presented in isolation at their optimal viewing position. Refixations were found to be preferentially directed toward the region of the word that contained the critical letters for distinguishing it from its competitors. In Experiments 1 and 2, low-frequency stimulus words sharing all letters except the initial ones with a high-frequency stimulus word (critical letters at the beginning of the word) elicited more left refixations than low-frequency stimulus words sharing all letters except the final ones with a high-frequency stimulus word (critical letters at the end of the word). A similar result was found in Experiments 3 and 4, using an orthographic priming paradigm. These results suggest that refixations are linked to the selection stage of lexical access, aimed at isolating a single lexical entry among a set of candidates activated during the first fixation.

  7. Brain signatures of meaning access in action word recognition.

    PubMed

    Pulvermüller, Friedemann; Shtyrov, Yury; Ilmoniemi, Risto

    2005-06-01

    The brain basis of action words may be neuron ensembles binding language- and action-related information that are dispersed over both language- and action-related cortical areas. This predicts fast spreading of neuronal activity from language areas to specific sensorimotor areas when action words semantically related to different parts of the body are being perceived. To test this, fast neurophysiological imaging was applied to reveal spatiotemporal activity patterns elicited by words with different action-related meaning. Spoken words referring to actions involving the face or leg were presented while subjects engaged in a distraction task and their brain activity was recorded using high-density magnetoencephalography. Shortly after the words could be recognized as unique lexical items, objective source localization using minimum norm current estimates revealed activation in superior temporal (130 msec) and inferior frontocentral areas (142-146 msec). Face-word stimuli activated inferior frontocentral areas more strongly than leg words, whereas the reverse was found at superior central sites (170 msec), thus reflecting the cortical somatotopy of motor actions signified by the words. Significant correlations were found between local source strengths in the frontocentral cortex calculated for all participants and their semantic ratings of the stimulus words, thus further establishing a close relationship between word meaning access and neurophysiology. These results show that meaning access in action word recognition is an early automatic process ref lected by spatiotemporal signatures of word-evoked activity. Word-related distributed neuronal assemblies with specific cortical topographies can explain the observed spatiotemporal dynamics reflecting word meaning access.

  8. From Words to Concepts: Focusing on Word Knowledge When Teaching for Conceptual Understanding within an Inquiry-Based Science Setting

    ERIC Educational Resources Information Center

    Haug, Berit S.; Ødegaard, Marianne

    2014-01-01

    This qualitative video study explores how two elementary school teachers taught for conceptual understanding throughout different phases of science inquiry. The teachers implemented teaching materials with a focus on learning science key concepts through the development of word knowledge. A framework for word knowledge was applied to examine the…

  9. Finding Words in a Language that Allows Words without Vowels

    ERIC Educational Resources Information Center

    El Aissati, Abder; McQueen, James M.; Cutler, Anne

    2012-01-01

    Across many languages from unrelated families, spoken-word recognition is subject to a constraint whereby potential word candidates must contain a vowel. This constraint minimizes competition from embedded words (e.g., in English, disfavoring "win" in "twin" because "t" cannot be a word). However, the constraint would be counter-productive in…

  10. On the meaning of the word 'epimutation'.

    PubMed

    Oey, H; Whitelaw, E

    2014-12-01

    The word 'epimutation' is often used in a manner that can be misinterpreted. The strict definition of epimutation is a heritable change in gene activity that is not associated with a DNA mutation but rather with gain or loss of DNA methylation or other heritable modifications of chromatin. Unfortunately, there is a growing tendency in the cancer field to use the word in situations in which underlying DNA sequence changes have occurred.

  11. Waste-Activated Sludge Fermentation for Polyacrylamide Biodegradation Improved by Anaerobic Hydrolysis and Key Microorganisms Involved in Biological Polyacrylamide Removal

    PubMed Central

    Dai, Xiaohu; Luo, Fan; Zhang, Dong; Dai, Lingling; Chen, Yinguang; Dong, Bin

    2015-01-01

    During the anaerobic digestion of dewatered sludge, polyacrylamide (PAM), a chemical conditioner, can usually be consumed as a carbon and nitrogen source along with other organic matter (e.g., proteins and carbohydrates in the sludge). However, a significant accumulation of acrylamide monomers (AMs) was observed during the PAM biodegradation process. To improve the anaerobic hydrolysis of PAM, especially the amide hydrolysis process, and to avoid the generation of the intermediate product AM, a new strategy is reported herein that uses an initial pH of 9, 200 mg COD/L of PAM and a fermentation time of 17 d. First, response surface methodology (RSM) was applied to optimize PAM removal in the anaerobic digestion of the sludge. The biological hydrolysis of PAM reached 86.64% under the optimal conditions obtained from the RSM. Then, the mechanisms for the optimized parameters that significantly improved the biological hydrolysis of PAM were investigated by the synergistic effect of the main organic compounds in the sludge, the floc size distribution, and the enzymatic activities. Finally, semi-continuous-flow experiments for a microbial community study were investigated based on the determination of key microorganisms involved in the biological hydrolysis of PAM. PMID:26144551

  12. RNA interference (RNAi)-induced suppression of nicotine demethylase activity reduces levels of a key carcinogen in cured tobacco leaves.

    PubMed

    Lewis, Ramsey S; Jack, Anne M; Morris, Jerry W; Robert, Vincent J M; Gavilano, Lily B; Siminszky, Balazs; Bush, Lowell P; Hayes, Alec J; Dewey, Ralph E

    2008-05-01

    Technologies for reducing the levels of tobacco product constituents that may contribute to unwanted health effects are desired. Target compounds include tobacco-specific nitrosamines (TSNAs), a class of compounds generated through the nitrosation of pyridine alkaloids during the curing and processing of tobacco. Studies have reported the TSNA N'-nitrosonornicotine (NNN) to be carcinogenic in laboratory animals. NNN is formed via the nitrosation of nornicotine, a secondary alkaloid produced through enzymatic N-demethylation of nicotine. Strategies to lower nornicotine levels in tobacco (Nicotiana tabacum L.) could lead to a corresponding decrease in NNN accumulation in cured leaves. The major nicotine demethylase gene of tobacco has recently been isolated. In this study, a large-scale field trial was conducted to evaluate transgenic lines of burley tobacco carrying an RNA interference (RNAi) construct designed to inhibit the expression of this gene. Selected transgenic lines exhibited a six-fold decrease in nornicotine content relative to untransformed controls. Analysis of cured leaves revealed a commensurate decrease in NNN and total TSNAs. The inhibition of nicotine demethylase activity is an effective means of decreasing significantly the level of a key defined animal carcinogen present in tobacco products.

  13. Receptor Activator for Nuclear Factor kappa B Ligand (RANKL) as an osteoimmune key regulator in bone physiology and pathology.

    PubMed

    Narducci, Paola; Bareggi, Renato; Nicolin, Vanessa

    2011-02-01

    The strength and integrity of the human skeleton depends on a delicate equilibrium between bone resorption and bone formation. Bone resorption is an elementary cellular activity in the modelling of the skeleton during growth and development. Later in life a most important physiological process in the skeleton is bone remodelling, which is locally initiated by resorption. During remodelling bone resorption is coupled to new bone formation that ensures renewal of bone with only minor local and temporary bone loss. Cells responsible for bone resorption and subsequent bone formation are the osteoclasts and osteoblasts, respectively. The osteoclast is derived from the pluripotent hematopoietic stem cell, which gives rise to a myeloid stem cell that can further differentiate into megakaryocytes, granulocytes, monocytes/macrophages and osteoclasts. The respective bone resorbing and forming actions of osteoclasts and osteoblasts are finely coupled, so that bone mass remains remarkably stable in a healthy adult. Imbalance between osteoclast and osteoblast activities can arise from a wide variety of hormonal changes or perturbations of inflammatory and growth factors resulting in postmenopausal osteoporosis, Paget's disease, lytic bone metastases, or rheumatoid arthritis, leading to increased bone resorption and crippling bone damage. In view of the critical role of osteoclasts in diverse pathology, there has been immense effort aimed at understanding the biology of this unique cell. The present review is focused on the current knowledge of the mechanisms that regulate the functional links between bone turnover and the immune system helping us to understand the main factors that lead to bone loss observed in osteoporosis, cancer and in rheumatoid arthritis. The aim of this review paper is to consider the key molecular interactions involved in the formation of osteoclast cells in normal and pathological conditions.

  14. Starting Right: Using "Biophilia," Organism Cards, & Key Themes in Biology to Introduce Student-Centered Active-Learning Strategies at the Beginning of a Course

    ERIC Educational Resources Information Center

    Metzger, Kelsey

    2013-01-01

    To create rich learning experiences, it is important to engage students from the very beginning of a course and lay the foundation for constructing a community of active learners. The activities described here using "organism cards" connect students' previous knowledge to course goals and address key themes in biology while initiating…

  15. The Wonders of Word Walls.

    ERIC Educational Resources Information Center

    Houle, Amy; Krogness, Allison

    2001-01-01

    Describes using a word wall, a visible display categorizing words alphabetically, enabling children in early childhood classrooms to discover new words and to practice and expand their language skills. Suggests that a word wall helps to create a secure learning environment, builds student confidence, and contributes to independent reading and…

  16. Words: What Goes with What?

    ERIC Educational Resources Information Center

    Murphy, Joseph A.

    Techniques for teaching collocation and word-association recognition as applied to the English as a second language class are suggested. Collocations are defined as phrases made of words which usually occur together, like "for the time being." Collocations and word associations are treated as synonymous. It is suggested that some words ought to be…

  17. Conceptually based vocabulary intervention: second graders' development of vocabulary words.

    PubMed

    Dimling, Lisa M

    2010-01-01

    An instructional strategy was investigated that addressed the needs of deaf and hard of hearing students through a conceptually based sign language vocabulary intervention. A single-subject multiple-baseline design was used to determine the effects of the vocabulary intervention on word recognition, production, and comprehension. Six students took part in the 30-minute intervention over 6-8 weeks, learning 12 new vocabulary words each week by means of the three intervention components: (a) word introduction, (b) word activity (semantic mapping), and (c) practice. Results indicated that the vocabulary intervention successfully improved all students' recognition, production, and comprehension of the vocabulary words and phrases.

  18. Key Words in Instruction. Online Learning and Virtual Schools

    ERIC Educational Resources Information Center

    Lamb, Annette; Callison, Daniel

    2005-01-01

    Online learning and virtual schools allow students to take classes any time and anywhere. These emerging learning environments require school library media specialists to expand their thinking about their resources and services. Creation of a virtual library can provide access to remote materials that enhance the experience of online learners.…

  19. Retrieving Images Verbally: No More Key Words and Other Heresies.

    ERIC Educational Resources Information Center

    Small, Jocelyn Penny

    1991-01-01

    Describes the development of a system to retrieve images for an international project that is producing a pictorial dictionary of classical mythology, the Lexicon Iconographicum Mythologiae Classicae. Applications to other types of information are discussed, two classification systems for Art History are described, and design principles for…

  20. Antibacterial activity of silver nanoparticles target sara through srna-teg49, a key mediator of hfq, in staphylococcus aureus

    PubMed Central

    Tian, Hu; Liao, Qiande; Liu, Meizhou; Hou, Jianhong; Zhang, Yangde; Liu, Ju

    2015-01-01

    Attributed to its antimicrobial effect, Silver nanoparticles (AgNPs) is widely used in various fields, such as biomedicine, textiles, health care products and food, etc. However, the antibacterial mechanism of AgNPs in staphylococcus aureus (S. aureus) by regulating sRNA expression remains largely unknown. Objectives: This study was performed to investigate the involvement of the antibacterial mechanism of AgNPs through sRNA-TEG49, a key mediator of Hfq, in S. aureus. Methods: Through the antimicrobial tests of AgNPs, its antibacterial laps and minimum inhibitory concentration was measured. A hierarchical cluster analysis of the differentially expressed sRNA in S. aureus was performed to investigate the relationship between AgNPs and sRNA. Expression of genes was analyzed by real-time PCR. Results: In the present study we found that at the concentrations higher than 1 mg/L, AgNPs could completely restrain bacteria growth, and the antibacterial activity of AgNPs apparently declined at the concentrations lower than 1 mg/L. S. aureus exposure to AgNPs, the expression of sRNA-TEG49, Hfq and sarA was significantly up-regulated in wild-type S. aureus. Moreover, Hfq loss-of-function inhibited the expression of sRNA-TEG49 in mutant-type S. aureus. Furthermore, sRNA-TEG49 loss-of-function associated with down-regulation the expression of sarA in mutant-type S. aureus. Conclusions: It was reasonable that Hfq regulated a distinct underlying molecular and antibacterial mechanism of AgNPs by forming a positive feedback loop with sRNA-TEG49. These observations suggested that Hfq plays an important role in the antibacterial mechanism of AgNPs by regulating sRNA-TEG49 expression, via its target sarA. PMID:26131167

  1. Is Active Management the Key to the Conservation of Saproxylic Biodiversity? Pollarding Promotes the Formation of Tree Hollows

    PubMed Central

    Sebek, Pavel; Altman, Jan; Platek, Michal; Cizek, Lukas

    2013-01-01

    Trees with hollows are key features sustaining biodiversity in wooded landscapes. They host rich assemblages of often highly specialised organisms. Hollow trees, however, have become rare and localised in Europe. Many of the associated biota is thus declining or endangered. The challenge of its conservation, therefore, is to safeguard the presence of hollow trees in sufficient numbers. Populations of numerous species associated with tree hollows and dead wood are often found in habitats that were formed by formerly common traditional silvicultural practices such as coppicing, pollarding or pasture. Although it has been occasionally mentioned that such practices increase the formation of hollows and the availability of often sun-exposed dead wood, their effect has never been quantified. Our study examined the hollow incidence in pollard and non-pollard (unmanaged) willows and the effect of pollarding on incremental growth rate by tree ring analysis. The probability of hollow occurrence was substantially higher in pollard than in non-pollard trees. Young pollards, especially, form hollows much more often than non-pollards; for instance, in trees of 50 cm DBH, the probability of hollow ocurrence was ∼0.75 in pollards, but only ∼0.3 in non-pollards. No difference in growth rate was found. Pollarding thus leads to the rapid formation of tree hollows, a habitat usually associated with old trees. It is therefore potentially a very important tool in the restoration of saproxylic habitats and conservation of hollow-dependent fauna. If applied along e.g. roads and watercourses, pollarding could also be used to increase landscape connectivity for saproxylic organisms. In reserves where pollarding was formerly practiced, its restoration would be necessary to prevent loss of saproxylic biodiversity. Our results point to the importance of active management measures for maintaining availability, and spatial and temporal continuity of deadwood microhabitats. PMID:23544142

  2. Representing Microbial Dormancy in Soil Decomposition Models Improves Model Performance and Reveals Key Ecosystem Controls on Microbial Activity

    NASA Astrophysics Data System (ADS)

    He, Y.; Yang, J.; Zhuang, Q.; Wang, G.; Liu, Y.

    2014-12-01

    Climate feedbacks from soils can result from environmental change and subsequent responses of plant and microbial communities and nutrient cycling. Explicit consideration of microbial life history traits and strategy may be necessary to predict climate feedbacks due to microbial physiology and community changes and their associated effect on carbon cycling. In this study, we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of dormancy at six temperate forest sites with observed soil efflux ranged from 4 to 10 years across different forest types. We then extrapolated the model to all temperate forests in the Northern Hemisphere (25-50°N) to investigate spatial controls on microbial and soil C dynamics. Both models captured the observed soil heterotrophic respiration (RH), yet no-dormancy model consistently exhibited large seasonal amplitude and overestimation in microbial biomass. Spatially, the total RH from temperate forests based on dormancy model amounts to 6.88PgC/yr, and 7.99PgC/yr based on no-dormancy model. However, no-dormancy model notably overestimated the ratio of microbial biomass to SOC. Spatial correlation analysis revealed key controls of soil C:N ratio on the active proportion of microbial biomass, whereas local dormancy is primarily controlled by soil moisture and temperature, indicating scale-dependent environmental and biotic controls on microbial and SOC dynamics. These developments should provide essential support to modeling future soil carbon dynamics and enhance the avenue for collaboration between empirical soil experiment and modeling in the sense that more microbial physiological measurements are needed to better constrain and evaluate the models.

  3. Dictionary Pruning with Visual Word Significance for Medical Image Retrieval

    PubMed Central

    Zhang, Fan; Song, Yang; Cai, Weidong; Hauptmann, Alexander G.; Liu, Sidong; Pujol, Sonia; Kikinis, Ron; Fulham, Michael J; Feng, David Dagan; Chen, Mei

    2016-01-01

    Content-based medical image retrieval (CBMIR) is an active research area for disease diagnosis and treatment but it can be problematic given the small visual variations between anatomical structures. We propose a retrieval method based on a bag-of-visual-words (BoVW) to identify discriminative characteristics between different medical images with Pruned Dictionary based on Latent Semantic Topic description. We refer to this as the PD-LST retrieval. Our method has two main components. First, we calculate a topic-word significance value for each visual word given a certain latent topic to evaluate how the word is connected to this latent topic. The latent topics are learnt, based on the relationship between the images and words, and are employed to bridge the gap between low-level visual features and high-level semantics. These latent topics describe the images and words semantically and can thus facilitate more meaningful comparisons between the words. Second, we compute an overall-word significance value to evaluate the significance of a visual word within the entire dictionary. We designed an iterative ranking method to measure overall-word significance by considering the relationship between all latent topics and words. The words with higher values are considered meaningful with more significant discriminative power in differentiating medical images. We evaluated our method on two public medical imaging datasets and it showed improved retrieval accuracy and efficiency. PMID:27688597

  4. Dictionary Pruning with Visual Word Significance for Medical Image Retrieval.

    PubMed

    Zhang, Fan; Song, Yang; Cai, Weidong; Hauptmann, Alexander G; Liu, Sidong; Pujol, Sonia; Kikinis, Ron; Fulham, Michael J; Feng, David Dagan; Chen, Mei

    2016-02-12

    Content-based medical image retrieval (CBMIR) is an active research area for disease diagnosis and treatment but it can be problematic given the small visual variations between anatomical structures. We propose a retrieval method based on a bag-of-visual-words (BoVW) to identify discriminative characteristics between different medical images with Pruned Dictionary based on Latent Semantic Topic description. We refer to this as the PD-LST retrieval. Our method has two main components. First, we calculate a topic-word significance value for each visual word given a certain latent topic to evaluate how the word is connected to this latent topic. The latent topics are learnt, based on the relationship between the images and words, and are employed to bridge the gap between low-level visual features and high-level semantics. These latent topics describe the images and words semantically and can thus facilitate more meaningful comparisons between the words. Second, we compute an overall-word significance value to evaluate the significance of a visual word within the entire dictionary. We designed an iterative ranking method to measure overall-word significance by considering the relationship between all latent topics and words. The words with higher values are considered meaningful with more significant discriminative power in differentiating medical images. We evaluated our method on two public medical imaging datasets and it showed improved retrieval accuracy and efficiency.

  5. Goodnight book: sleep consolidation improves word learning via storybooks

    PubMed Central

    Williams, Sophie E.; Horst, Jessica S.

    2014-01-01

    Reading the same storybooks repeatedly helps preschool children learn words. In addition, sleeping shortly after learning also facilitates memory consolidation and aids learning in older children and adults. The current study explored how sleep promotes word learning in preschool children using a shared storybook reading task. Children were either read the same story repeatedly or different stories and either napped after the stories or remained awake. Children's word retention were tested 2.5 h later, 24 h later, and 7 days later. Results demonstrate strong, persistent effects for both repeated readings and sleep consolidation on young children's word learning. A key finding is that children who read different stories before napping learned words as well as children who had the advantage of hearing the same story. In contrast, children who read different stories and remained awake never caught up to their peers on later word learning tests. Implications for educational practices are discussed. PMID:24624111

  6. Stress Assignment in Aphasia: Word and Non-Word Reading and Non-Word Repetition

    ERIC Educational Resources Information Center

    de Bree, Elise; Janse, Esther; van de Zande, Anne Marie

    2007-01-01

    This paper investigates stress assignment in Dutch aphasic patients in non-word repetition, as well as in real-word and non-word reading. Performance on the non-word reading task was similar for the aphasic patients and the control group, as mainly regular stress was assigned to the targets. However, there were group differences on the real-word…

  7. Addressing key concepts in physical geography through interactive learning activities in an online geo-ICT environment

    NASA Astrophysics Data System (ADS)

    Verstraeten, Gert; Steegen, An; Martens, Lotte

    2016-04-01

    The increasing number of geospatial datasets and free online geo-ICT tools offers new opportunities for education in Earth Sciences. Geospatial technology indeed provides an environment through which interactive learning can be introduced in Earth Sciences curricula. However, the effectiveness of such e-learning approaches in terms of learning outcomes has rarely been addressed. Here, we present our experience with the implementation of digital interactive learning activities within an introductory Physical Geography course attended by 90 undergraduate students in Geography, Geology, Biology and Archaeology. Two traditional lectures were replaced by interactive sessions (each 2 h) in a flexible classroom where students had to work both in team and individually in order to explore some key concepts through the integrated use of geospatial data within Google EarthTM. A first interactive lesson dealt with the classification of river systems and aimed to examine the conditions under which rivers tend to meander or to develop a braided pattern. Students were required to collect properties of rivers (river channel pattern, channel slope, climate, discharge, lithology, vegetation, etc). All these data are available on a global scale and have been added as separate map layers in Google EarthTM. Each student collected data for at least two rivers and added this information to a Google Drive Spreadsheet accessible to the entire group. This resulted in a database of more than one hundred rivers spread over various environments worldwide. In a second phase small groups of students discussed the potential relationships between river channel pattern and its controlling factors. Afterwards, the findings of each discussion group were presented to the entire audience. The same set-up was followed in a second interactive session to explore spatial variations in ecosystem properties such as net primary production and soil carbon content. The qualitative evaluation of both interactive

  8. Estimating verbal intelligence in unipolar depression: comparison of word definition and word recognition.

    PubMed

    Suslow, Thomas

    2009-01-01

    Depression is known to be associated with deficits in effortful processing and word fluency. Automatic processes, instead, appear largely intact in depressed patients. It was investigated whether active word definition could be a less appropriate method than passive word recognition as a measure of verbal intelligence in depression. The valid assessment of premorbid IQ is important for correct comparison with current cognitive efficiency of depressed individuals, since premorbid IQ serves as baseline or control parameter to estimate the extent and severity of acquired cognitive impairments, both in the clinical and the research context. Two vocabulary tests were administered to 90 patients (31 women) with unipolar depression and 30 control subjects (15 women): a word definition task [the vocabulary subtest of the Wechsler Adult Intelligence Scale (WAIS-R)] and a word recognition task [the Multiple choice vocabulary test (MWT)]. In the depressed sample, scores of the MWT tended to be higher than WAIS-R scores. For depressed women, the MWT score was significantly higher than the WAIS-R score. In the control sample, no differences between MWT and WAIS-R scores were observed. Our findings indicate that word definition tasks could underestimate verbal intelligence especially in depressed women. For depressed women, it could be more appropriate to administer word recognition than word definition as an estimate of premorbid or verbal intelligence.

  9. Fast ForWord.

    ERIC Educational Resources Information Center

    Education Commission of the States, Denver, CO.

    This paper provides an overview of Fast ForWord, a CD-ROM and Internet-based training program for children (pre-K to grade 8) with language and reading problems that helps children rapidly build oral language comprehension and other critical skills necessary for learning to read or becoming a better reader. With the help of computers, speech…

  10. The "N" Word.

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    1999-01-01

    In a lawsuit involving classroom and literary racial epithets, the Ninth Circuit Court remanded the racial-harassment claim, not the book-removal claim. The ultimate outcome awaits trial; the court's Solomonic decision needs further testing. Meanwhile, the "N" word is a no-no for teachers and students, but not necessarily for books. (MLH)

  11. They Love Words.

    ERIC Educational Resources Information Center

    Aiken, Adel G.; Bayer, Lisa

    2002-01-01

    Describes how teachers implement a spelling decoding strategy within a first-grade language arts curriculum. Considers how the investigation of one spelling-decoding instructional strategy was a coming-to-know process that led the authors to value intentional word study that was connected to but not necessarily embedded in authentic contexts. (SG)

  12. Fractals with Word.

    ERIC Educational Resources Information Center

    Milner, Jim; Hodgson, Cris; Moore, Kate; Wheatley, Vicky

    2002-01-01

    It is surprisingly easy to explore geometry using Word AutoShapes or an Excel spreadsheet. Most of the techniques described could be taught to Y7 in half an hour. Many of them could be used in primary schools. Shows some of the mathematical possibilities of these techniques. Detailed step-by-step worksheets to introduce pupils to these are…

  13. Word Attack Model.

    ERIC Educational Resources Information Center

    Follettie, Joseph F.

    A limited analysis of alternative approaches to phonemic-level word attack instruction is provided in this document. The instruction segment begins with training in letter-sound correspondences for which mastery of certain skills is assumed. Instruction ends with the decoding of novel items having a consonant-vowel-consonant construction. Contents…

  14. Generalizing Word Lattice Translation

    DTIC Science & Technology

    2008-02-01

    demonstrate substantial gains for Chinese -English and Arabic -English translation. Keywords: word lattice translation, phrase-based and hierarchical...introduce in reordering models. Our experiments evaluating the approach demonstrate substantial gains for Chinese -English and Arabic -English translation. 15...Section 4 presents two applications of the noisier channel paradigm, demonstrating substantial performance gains in Arabic -English and Chinese -English

  15. Inspecting Magic Words.

    ERIC Educational Resources Information Center

    White, John Howell

    1998-01-01

    Considers neopragmatism's use-value for art educators as they inspect the magic words, images, and practices that influence curriculum and instruction. Explains that neopragmatism offers art educators three concepts (contingency, demystification, and recontextualization) as tools to interpret educational beliefs and classroom practices. (CMK)

  16. Sparkling and Spinning Words.

    ERIC Educational Resources Information Center

    Carlson, Ruth Kearney

    1964-01-01

    Teachers should foster in children's writing the use of words with "sparkle" and "spin"--"sparkle" implying brightness and vitality, "spin" connoting industry, patience, and painstaking work. By providing creative listening experiences with good children's or adult literature, the teacher can encourage students to broaden their imaginations and…

  17. Offensive Words, Lethal Weapons

    ERIC Educational Resources Information Center

    Jacoby, Russell

    2007-01-01

    The old childhood ditty "sticks and stones may break my bones, but words will never hurt me" has proved wiser than the avalanche of commentary provoked by the recent insults by Don Imus and the killings at Virginia Tech. Our society forbids public name-calling but allows sticks and stones. Anyone can acquire a gun, but everyone must be…

  18. Reduplication facilitates early word segmentation.

    PubMed

    Ota, Mitsuhiko; Skarabela, Barbora

    2017-02-06

    This study explores the possibility that early word segmentation is aided by infants' tendency to segment words with repeated syllables ('reduplication'). Twenty-four nine-month-olds were familiarized with passages containing one novel reduplicated word and one novel non-reduplicated word. Their central fixation times in response to these as well as new reduplicated and non-reduplicated words introduced at test showed that familiarized reduplicated words were segmented better than familiarized non-reduplicated words. These results demonstrate that infants are predisposed to segment words with repeated phonological elements, and suggest that register-specific words in infant-directed speech may have evolved in response to this learning bias.

  19. The Slow Developmental Time Course of Real-Time Spoken Word Recognition

    ERIC Educational Resources Information Center

    Rigler, Hannah; Farris-Trimble, Ashley; Greiner, Lea; Walker, Jessica; Tomblin, J. Bruce; McMurray, Bob

    2015-01-01

    This study investigated the developmental time course of spoken word recognition in older children using eye tracking to assess how the real-time processing dynamics of word recognition change over development. We found that 9-year-olds were slower to activate the target words and showed more early competition from competitor words than…

  20. Concreteness effects in bilingual and monolingual word learning.

    PubMed

    Kaushanskaya, Margarita; Rechtzigel, Katrina

    2012-10-01

    Previous studies have demonstrated that bilingualism can facilitate novel-word learning. However, the mechanisms behind this bilingual advantage remain unknown. Here, we examined whether bilinguals may be more sensitive to semantic information associated with the novel words. To that end, we manipulated the concreteness of the referent in the word-learning paradigm, since concrete words have been shown to activate the semantic system more robustly than abstract words do. The results revealed that the bilingual advantage was stronger for novel words learned in association with concrete rather than abstract referents. These findings suggest that bilingual advantages for word learning may be rooted, at least in part, in bilinguals' greater sensitivity to semantic information during learning.

  1. Statistical Word Learning at Scale: The Baby's View Is Better

    ERIC Educational Resources Information Center

    Yurovsky, Daniel; Smith, Linda B.; Yu, Chen

    2013-01-01

    A key question in early word learning is how children cope with the uncertainty in natural naming events. One potential mechanism for uncertainty reduction is cross-situational word learning--tracking word/object co-occurrence statistics across naming events. But empirical and computational analyses of cross-situational learning have made strong…

  2. Predicting the birth of a spoken word

    PubMed Central

    Roy, Brandon C.; Frank, Michael C.; DeCamp, Philip; Miller, Matthew; Roy, Deb

    2015-01-01

    Children learn words through an accumulation of interactions grounded in context. Although many factors in the learning environment have been shown to contribute to word learning in individual studies, no empirical synthesis connects across factors. We introduce a new ultradense corpus of audio and video recordings of a single child’s life that allows us to measure the child’s experience of each word in his vocabulary. This corpus provides the first direct comparison, to our knowledge, between different predictors of the child’s production of individual words. We develop a series of new measures of the distinctiveness of the spatial, temporal, and linguistic contexts in which a word appears, and show that these measures are stronger predictors of learning than frequency of use and that, unlike frequency, they play a consistent role across different syntactic categories. Our findings provide a concrete instantiation of classic ideas about the role of coherent activities in word learning and demonstrate the value of multimodal data in understanding children’s language acquisition. PMID:26392523

  3. KEY COMPARISON: Activity measurements of the radionuclide 153Sm for the ANSTO, Australia in the ongoing comparison BIPM.RI(II)-K1.Sm-153

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Reinhard, M.; Alexiev, D.; Mo, L.

    2005-01-01

    In 2004, the Australian Nuclear Science and Technology Organisation (ANSTO) submitted two samples of known activity of 153Sm to the International Reference System (SIR). The value of the activity submitted was about 920 MBq. This key comparison result has been added to the matrix of degrees of equivalence in the key comparison database that now contains five results, identifier BIPM.RI(II)-K1.Sm-153. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), according to the provisions of the Mutual Recognition Arrangement (MRA).

  4. Key Nutrients.

    ERIC Educational Resources Information Center

    Federal Extension Service (USDA), Washington, DC.

    Lessons written to help trainer agents prepare aides for work with families in the Food and Nutrition Program are presented in this booklet. The key nutrients discussed in the 10 lessons are protein, carbohydrates, fat, calcium, iron, iodine, and Vitamins A, B, C, and D. the format of each lesson is as follows: Purpose, Presentation, Application…

  5. Infants Track Word Forms in Early Word-Object Associations

    ERIC Educational Resources Information Center

    Zamuner, Tania S.; Fais, Laurel; Werker, Janet F.

    2014-01-01

    A central component of language development is word learning. One characterization of this process is that language learners discover objects and then look for word forms to associate with these objects (Mcnamara, 1984; Smith, 2000). Another possibility is that word forms themselves are also important, such that once learned, hearing a familiar…

  6. Word Maturity: A New Metric for Word Knowledge

    ERIC Educational Resources Information Center

    Landauer, Thomas K.; Kireyev, Kirill; Panaccione, Charles

    2011-01-01

    A new metric, Word Maturity, estimates the development by individual students of knowledge of every word in a large corpus. The metric is constructed by Latent Semantic Analysis modeling of word knowledge as a function of the reading that a simulated learner has done and is calibrated by its developing closeness in information content to that of a…

  7. Word Savvy: Integrating Vocabulary, Spelling, and Word Study

    ERIC Educational Resources Information Center

    Brand, Max

    2004-01-01

    Tired of assigning weekly spelling lists that students memorize for the test only to have them misspell the words in their daily writing? Then join Max Brand in his fifth-grade classroom where word learning is integrated fully into literacy workshops. Using spelling investigations, word study notebooks, reading logs, and writers' notebooks,…

  8. Cascaded processing in written compound word production

    PubMed Central

    Bertram, Raymond; Tønnessen, Finn Egil; Strömqvist, Sven; Hyönä, Jukka; Niemi, Pekka

    2015-01-01

    In this study we investigated the intricate interplay between central linguistic processing and peripheral motor processes during typewriting. Participants had to typewrite two-constituent (noun-noun) Finnish compounds in response to picture presentation while their typing behavior was registered. As dependent measures we used writing onset time to assess what processes were completed before writing and inter-key intervals to assess what processes were going on during writing. It was found that writing onset time was determined by whole word frequency rather than constituent frequencies, indicating that compound words are retrieved as whole orthographic units before writing is initiated. In addition, we found that the length of the first syllable also affects writing onset time, indicating that the first syllable is fully prepared before writing commences. The inter-key interval results showed that linguistic planning is not fully ready before writing, but cascades into the motor execution phase. More specifically, inter-key intervals were largest at syllable and morpheme boundaries, supporting the view that additional linguistic planning takes place at these boundaries. Bigram and trigram frequency also affected inter-key intervals with shorter intervals corresponding to higher frequencies. This can be explained by stronger memory traces for frequently co-occurring letter sequences in the motor memory for typewriting. These frequency effects were even larger in the second than in the first constituent, indicating that low-level motor memory starts to become more important during the course of writing compound words. We discuss our results in the light of current models of morphological processing and written word production. PMID:25954182

  9. EPRRI's Research Activities into the Impact of Key NCLBA Requirements. EPRRI Policy Updates. Issue Three, Fall 2004.

    ERIC Educational Resources Information Center

    Educational Policy Reform Research Institute, 2004

    2004-01-01

    The Educational Policy Reform Research Institute (EPRRI), with funding from the U.S. Department of Education's Office of Special Education Programs, investigates the impact of educational accountability reforms on students with disabilities and on special education. EPRRI addresses the research needs of policymakers and other key stakeholders by…

  10. Automatic Word Alignment

    DTIC Science & Technology

    2014-02-18

    strategy was evalu­ ated in the context of English -to-Pashto (E2P) and Pashto-to- English (P2E), a low-resource language pair. For E2P, the training and...improves the quality of automatic word alignment, for example for resource poor language pairs, thus improving Statistical Machine Translation (SMT...example for resource poor language pairs, thus improving Statistical Machine Translation (SMT) performance. 15. SUBJECT TERMS 16. SECURITY

  11. Hypnosis: medicine's dirty word.

    PubMed

    Upshaw, William N

    2006-10-01

    This paper attempts to understand the relationship between the clinical efficacy of hypnosis and its negative perception among many medical educators, practitioners and the general public. By exploring the history of hypnosis, an attempt was made to point out several events that may have led to both the past and current misperception of hypnosis which the author believes have caused hypnosis to become "medicine's dirty word".

  12. Anhedonia and emotional word memory in patients with depression.

    PubMed

    Liu, Wen-Hua; Wang, Ling-Zhi; Zhao, Su-Hua; Ning, Yu-Ping; Chan, Raymond C K

    2012-12-30

    Anhedonia is a key diagnostic criterion for major depression. Investigating the relation between the specific symptoms and emotional processing may help to understand the underlying cognitive mechanism of anhedonia in depression. In this study, we explored the potential association between memory for emotional words and anhedonia in 71 patients with depression and 61 healthy individuals. An emotional word-rating task was administered to assess self-reported emotional experience to words on both valence and arousal dimensions, and subsequent recall and recognition memory for these words. Depressed patients demonstrated a reduction in pleasure and arousal experience to positive words, but an increase in arousal experience to negative words. Depressed patients also displayed a lower overall memory performance in recall measure and a bias to memory of more negative words. Moreover, state anhedonia and trait anhedonia were associated with attenuated positive experience and enhanced negative experience in patients with depression only. Higher levels of anhedonia and depression severity were also associated with fewer positive words and more negative words memory. Patients with depression displayed a flat pattern of emotional experience to positive stimuli and a tendency towards rating negative stimuli more intensely.

  13. Word learning: An ERP investigation of word experience effects on recognition and word processing

    PubMed Central

    Balass, Michal; Nelson, Jessica R.; Perfetti, Charles A.

    2012-01-01

    Adults of varying reading comprehension skill learned a set of previously unknown rare English words (e.g., gloaming) in three different learning conditions in which the type of word knowledge was manipulated. The words were presented in one of three conditions: (1) orthography-to-meaning (no phonology); (2) orthography-to-phonology (no meaning); and (3) phonology-to-meaning (no orthography). Following learning, participants made meaning judgments on the learned words, familiar known words, and unpresented (unlearned) rare words while their ERPs were recorded. The behavioral results showed no significant effects of comprehension skill on meaning judgment performance. Contrastingly, the ERP results indicated comprehension skill differences in P600 amplitude; high-skilled readers showed stronger familiarity effects for learned words, whereas less-skilled readers did not distinguish between learned words, familiar words, and unlearned words. Evidence from the P600 and N400 illustrated superior learning of meaning when meaning information was coupled with orthography rather than phonology. These results suggest that the availability of word knowledge (orthography, phonology, and meaning) at learning affects subsequent word identification processes when the words are encountered in a new context. PMID:22399833

  14. Hippocampus and nucleus accumbens activity during neutral word recognition related to trait physical anhedonia in patients with schizophrenia: an fMRI study.

    PubMed

    Lee, Jung Suk; Chun, Ji Won; Kang, Jee In; Kang, Dong-Il; Park, Hae-Jeong; Kim, Jae-Jin

    2012-07-30

    Emotional memory dysfunction may be associated with anhedonia in schizophrenia. This study aimed to investigate the neurobiological basis of emotional memory and its relationship with anhedonia in schizophrenia specifically in emotional memory relate brain regions of interest (ROIs) including the amygdala, hippocampus, nucleus accumbens, and ventromedial prefrontal cortex. Fourteen patients with schizophrenia and 16 healthy subjects performed a word-image associative encoding task, during which a neutral word was presented with a positive, neutral, or control image. Subjects underwent functional magnetic resonance imaging while performing the recognition task. Correlation analyses were performed between the percent signal change (PSC) in the ROIs and the anhedonia scores. We found no group differences in recognition accuracy and reaction time. The PSC of the hippocampus in the positive and neutral conditions, and the PSC in the nucleus accumbens in the control condition, appeared to be negatively correlated with the Physical Anhedonia Scale (PAS) scores in patients with schizophrenia, while significant correlations with the PAS scores were not observed in healthy subjects. This study provides further evidences of the role of the hippocampus and nucleus accumbens in trait physical anhedonia and possible associations between emotional memory deficit and trait physical anhedonia in patients with schizophrenia.

  15. COMPUTER-AIDED WORD RESEARCH.

    ERIC Educational Resources Information Center

    SILIAKUS, H.J.

    IN PREPARATION FOR THE DEVELOPMENT OF A GENERAL FREQUENCY WORD LIST IN GERMAN DESIGNED TO MEET THE NEEDS OF THE INTERMEDIATE AND ADVANCED LEVELS OF READING IN THE GERMAN CURRICULUM, A COMPUTER-BASED WORD COUNT WAS BEGUN IN AUSTRALIA'S UNIVERSITY OF ADELAIDE. USING MAGNETIC TAPES CONTAINING (1) A TEXT OF OVER 100,000 RUNNING WORDS, (2) 1,000 MOST…

  16. Word Recognition in Auditory Cortex

    ERIC Educational Resources Information Center

    DeWitt, Iain D. J.

    2013-01-01

    Although spoken word recognition is more fundamental to human communication than text recognition, knowledge of word-processing in auditory cortex is comparatively impoverished. This dissertation synthesizes current models of auditory cortex, models of cortical pattern recognition, models of single-word reading, results in phonetics and results in…

  17. Word Learning as Bayesian Inference

    ERIC Educational Resources Information Center

    Xu, Fei; Tenenbaum, Joshua B.

    2007-01-01

    The authors present a Bayesian framework for understanding how adults and children learn the meanings of words. The theory explains how learners can generalize meaningfully from just one or a few positive examples of a novel word's referents, by making rational inductive inferences that integrate prior knowledge about plausible word meanings with…

  18. Transformation of Words into Vocabulary

    ERIC Educational Resources Information Center

    Parveen, H. Naseema; Rajan, Premalatha

    2012-01-01

    This article explores the significance of a word and the changes it undergoes in its form when it is placed in the hierarchy of grammatical constituents thereby forming a new word termed as vocabulary. This change or transformation is the result of affixations. Transformation becomes essential as the words learnt cannot be used as such in a…

  19. Skipped words and fixated words are processed differently during reading.

    PubMed

    Eskenazi, Michael A; Folk, Jocelyn R

    2015-04-01

    The purpose of this study was to investigate whether words are processed differently when they are fixated during silent reading than when they are skipped. According to a serial processing model of eye movement control (e.g., EZ Reader) skipped words are fully processed (Reichle, Rayner, Pollatsek, Behavioral and Brain Sciences, 26(04):445-476, 2003), whereas in a parallel processing model (e.g., SWIFT) skipped words do not need to be fully processed (Engbert, Nuthmann, Richter, Kliegl, Psychological Review, 112(4):777-813, 2005). Participants read 34 sentences with target words embedded in them while their eye movements were recorded. All target words were three-letter, low-frequency, and unpredictable nouns. After the reading session, participants completed a repetition priming lexical decision task with the target words from the reading session included as the repetition prime targets, with presentation of those same words during the reading task acting as the prime. When participants skipped a word during the reading session, their reaction times on the lexical decision task were significantly longer (M = 656.42 ms) than when they fixated the word (M = 614.43 ms). This result provides evidence that skipped words are sometimes not processed to the same degree as fixated words during reading.

  20. Distinguishing Target From Distractor in Stroop, Picture–Word, and Word–Word Interference Tasks

    PubMed Central

    Schmalz, Xenia; Treccani, Barbara; Mulatti, Claudio

    2015-01-01

    Lexical selection—both during reading aloud and speech production—involves selecting an intended word, while ignoring irrelevant lexical activation. This process has been studied by the use of interference tasks. Examples are the Stroop task, where participants ignore the written color word and name the color of the ink, picture–word interference tasks, where participants name a picture while ignoring a super-imposed written word, or word–word interference (WWI) tasks, where two words are presented and the participants need to respond to only one, based on an pre-determined visual feature (e.g., color, position). Here, we focus on the WWI task: it is theoretically impossible for existing models to explain how the cognitive system can respond to one stimulus and block the other, when they are presented by the same modality (i.e., they are both words). We describe a solution that can explain performance on the WWI task: drawing on the literature on visual attention, we propose that the system creates an object file for each perceived object, which is continuously updated with increasingly complete information about the stimulus, such as the task-relevant visual feature. Such a model can account for performance on all three tasks. PMID:26696927

  1. Lexical Configuration and Lexical Engagement: When Adults Learn New Words

    PubMed Central

    Leach, Laura; Samuel, Arthur G.

    2007-01-01

    People know thousands of words in their native language, and each of these words must be learned at some time in the person's lifetime. A large number of these words will be learned when the person is an adult, reflecting the fact that the mental lexicon is continuously changing. We explore how new words get added to the mental lexicon, and provide empirical support for a theoretical distinction between what we call lexical configuration and lexical engagement. Lexical configuration is the set of factual knowledge associated with a word (e.g., the word's sound, spelling, meaning, or syntactic role). Almost all previous research on word learning has focused on this aspect. However it is also critical to understand the process by which a word becomes capable of lexical engagement – the ways in which a lexical entry dynamically interacts with other lexical entries, and with sublexical representations. For example, lexical entries compete with each other during word recognition (inhibition within the lexical level), and they also support the activation of their constituents (top-down lexical-phonemic facilitation, and lexically-based perceptual learning). We systematically vary the learning conditions for new words, and use separate measures of lexical configuration and engagement. Several surprising dissociations in behavior demonstrate the importance of the theoretical distinction between configuration and engagement. PMID:17367775

  2. [Change in the activity of the key gluconeogenesis enzymes in the rat liver and kidneys during the action of subextreme and extreme factors on the body].

    PubMed

    Panin, L E; Kolosova, I E; Nechaev, Iu S

    1979-06-01

    The activity of glucogenesis key enzymes (phosphoenolpyruvate carboxinase, fructoso-1,6-siphosphatase, glucoso-6-phosphatase) of the rat liver and kidneys was studied simultaneously under the effect of extreme and subextreme factors on the organism. The low initial phosphoenolpyruvate carboxikinase activity in the liver and its high inductivity under extreme conditions suggest a role of this enzyme as limiting link in glyconeogenesis. The activity of phosphoenolpyruvate carboxinase in the kidneys is comparable to that of fructoso-1,6-diphosphatase; it is considerably higher than the activity of glucoso-6-phosphatase. The phosphoenolpyruvate carboxinase activity in the kidneys is 5--6 times higher than in the liver. The activity of phosphoenolpyruvate carboxinase and glucoso-6-phosphatase is increased under the effect of extreme factors, and that of fructoso-1,6-diphosphatase remains unchanged. The lack of clear synchronous changes in the activity of glucogenesis key enzymes in the liver and kidneys indicates that the cells of these organs do not provide the united operon for phosphoenolpyruvate carboxinase, fructoso-1,6-diphosphatase and glucoso-6-phosphatase with common regulation mechanism.

  3. p38 MAPK Is Activated but Does Not Play a Key Role during Apoptosis Induction by Saturated Fatty Acid in Human Pancreatic β-Cells

    PubMed Central

    Šrámek, Jan; Němcová-Fürstová, Vlasta; Balušíková, Kamila; Daniel, Petr; Jelínek, Michael; James, Roger F.; Kovář, Jan

    2016-01-01

    Saturated stearic acid (SA) induces apoptosis in the human pancreatic β-cells NES2Y. However, the molecular mechanisms involved are unclear. We showed that apoptosis-inducing concentrations of SA activate the p38 MAPK signaling pathway in these cells. Therefore, we tested the role of p38 MAPK signaling pathway activation in apoptosis induction by SA in NES2Y cells. Crosstalk between p38 MAPK pathway activation and accompanying ERK pathway inhibition after SA application was also tested. The inhibition of p38 MAPK expression by siRNA silencing resulted in a decrease in MAPKAPK-2 activation after SA application, but it had no significant effect on cell viability or the level of phosphorylated ERK pathway members. The inhibition of p38 MAPK activity by the specific inhibitor SB202190 resulted in inhibition of MAPKAPK-2 activation and noticeable activation of ERK pathway members after SA treatment but in no significant effect on cell viability. p38 MAPK overexpression by plasmid transfection produced an increase in MAPKAPK-2 activation after SA exposure but no significant influence on cell viability or ERK pathway activation. The activation of p38 MAPK by the specific activator anisomycin resulted in significant activation of MAPKAPK-2. Concerning the effect on cell viability, application of the activator led to apoptosis induction similar to application of SA (PARP cleavage and caspase-7, -8, and -9 activation) and in inhibition of ERK pathway members. We demonstrated that apoptosis-inducing concentrations of SA activate the p38 MAPK signaling pathway and that this activation could be involved in apoptosis induction by SA in the human pancreatic β-cells NES2Y. However, this involvement does not seem to play a key role. Crosstalk between p38 MAPK pathway activation and ERK pathway inhibition in NES2Y cells seems likely. Thus, the ERK pathway inhibition by p38 MAPK activation does not also seem to be essential for SA-induced apoptosis. PMID:26861294

  4. On modelling with words

    NASA Astrophysics Data System (ADS)

    Novák, Vilém

    2013-01-01

    In this paper, we discuss a class of methods encapsulated under the term modelling with words. The theoretical frame is mathematical fuzzy logic in broader sense, namely its constituents: formal logical theory of evaluative linguistic expressions, intermediate quantifiers, and the related concepts of linguistic description and perception-based logical deduction. We present various kinds of applications based on this theory: control of complex processes, managerial decision making, analysis, forecasting and linguistic evaluation of time series, mining linguistic associations, and also linguistic summarization and deduction based on intermediate quantifier theory.

  5. Annotating WordNet

    DTIC Science & Technology

    2004-01-01

    the subject of long de- bate (see the Hanks and Kilgarriff papers for two recent contributions). These are topics in need of serious con- sideration...classic example, its unrelated senses being “river bank” and “financial institution.” WordNet does not make a distinction between homonymy and polysemy ...Prescribed by ANSI Std Z39-18 a manual sense-tagging system, and it is these we will concentrate on here. The difficulties inherent in the sense

  6. Understanding central carbon metabolism of rapidly proliferating mammalian cells based on analysis of key enzymatic activities in GS-CHO cell lines.

    PubMed

    Zou, Wu; Al-Rubeai, Mohamed

    2016-09-01

    The central carbon metabolism (glycolysis, the pentose phosphate pathway [PPP], and the tricarboxylic acid [TCA] cycle) plays an essential role in the supply of biosynthetic precursors and energy. How the central carbon metabolism changes with the varying growth rates in the in vitro cultivation of rapidly proliferating mammalian cells, such as cancer cells and continuous cell lines for recombinant protein production, remains elusive. Based on relationships between the growth rate and the activity of seven key enzymes from six cell clones, this work reports finding an important metabolic characteristic in rapidly proliferating glutamine synthetase-Chinese hamster ovary cells. The key enzymatic activity involved in the TCA cycle that is responsible for the supply of energy became elevated as the growth rate exhibited increases, while the activity of key enzymes in metabolic pathways (glycolysis and the PPP), responsible for the supply of biosynthetic precursors, tended to decrease-suggesting that rapidly proliferating cells still depended predominantly on the TCA cycle rather than on aerobic glycolysis for their energetic demands. Meanwhile, the growth-limiting resource was most likely biosynthetic substrates rather than energy provision. In addition, the multifaceted role of glucose-6-phosphate isomerase (PGI) was confirmed, based on a significant correlation between PGI activity and the percentage of G2/M-phase cells.

  7. KEY COMPARISON: Update of the BIPM comparison BIPM.RI(II)-K1.F-18 of activity measurements of the radionuclide 18F to include the NPL

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Woods, M. J.

    2003-01-01

    Since 2001, four national metrology institutes (NMIs) have submitted four samples of known activity of 18F to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures, the most recent being that of the NPL (UK). The activities ranged from about 1 MBq to 8 MBq. The key comparison reference value (KCRV) has been recalculated to include the latest value and the degrees of equivalence between each equivalent activity measured in the SIR and the key comparison reference value (KCRV) have been calculated and the results are given in the form of a matrix. A graphical presentation is also given. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), comparison identifier BIPM.RI(II)-K1.F-18, according to the provisions of the Mutual Recognition Arrangement (MRA).

  8. KEY COMPARISON: Update of the BIPM comparison BIPM.RI(II)-K1.F-18 of activity measurements of the radionuclide 18F to include the CIEMAT

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; García-Toraño, E.; Los Arcos, J.-M.

    2004-01-01

    Since 2001, five national metrology institutes (NMIs) have submitted five samples of known activity of 18F to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), the most recent being that of the CIEMAT (Spain). The activities ranged from about 1 MBq to 18 MBq. The key comparison reference value (KCRV) has been recalculated to include the latest value and the degrees of equivalence between each equivalent activity measured in the SIR have been calculated and the results are given in the form of a matrix. A graphical presentation is also given for this key comparison with identifier BIPM.RI(II)-K1.F-18. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), according to the provisions of the Mutual Recognition Arrangement (MRA).

  9. KEY COMPARISON: Update of the BIPM comparison BIPM.RI(II)-K1.F-18 of activity measurements of the radionuclide 18F to include the PTB

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Kossert, K.; Janßen, H.

    2006-01-01

    Since 2001, six national metrology institutes (NMIs) have submitted six samples of known activity of 18F to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), the most recent being that of the PTB (Germany). The activities ranged from about 1 MBq to 18 MBq. The key comparison reference value (KCRV) has been recalculated to include the latest value, with the agreement of the CCRI(II). The degrees of equivalence between each equivalent activity measured in the SIR have been recalculated and the results are given in the form of a matrix. A graphical presentation is also given for this key comparison with identifier BIPM.RI(II)-K1.F-18. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), according to the provisions of the Mutual Recognition Arrangement (MRA).

  10. What Homophones Say about Words

    PubMed Central

    Dautriche, Isabelle; Chemla, Emmanuel

    2016-01-01

    The number of potential meanings for a new word is astronomic. To make the word-learning problem tractable, one must restrict the hypothesis space. To do so, current word learning accounts often incorporate constraints about cognition or about the mature lexicon directly in the learning device. We are concerned with the convexity constraint, which holds that concepts (privileged sets of entities that we think of as “coherent”) do not have gaps (if A and B belong to a concept, so does any entity “between” A and B). To leverage from it a linguistic constraint, learning algorithms have percolated this constraint from concepts, to word forms: some algorithms rely on the possibility that word forms are associated with convex sets of objects. Yet this does have to be the case: homophones are word forms associated with two separate words and meanings. Two sets of experiments show that when evidence suggests that a novel label is associated with a disjoint (non-convex) set of objects, either a) because there is a gap in conceptual space between the learning exemplars for a given word or b) because of the intervention of other lexical items in that gap, adults prefer to postulate homophony, where a single word form is associated with two separate words and meanings, rather than inferring that the word could have a disjunctive, discontinuous meaning. These results about homophony must be integrated to current word learning algorithms. We conclude by arguing for a weaker specialization of word learning algorithms, which too often could miss important constraints by focusing on a restricted empirical basis (e.g., non-homophonous content words). PMID:27583384

  11. Structural Descriptors of Zeolitic-Imidazolate Frameworks Are Keys to the Activity of Fe-N-C Catalysts.

    PubMed

    Armel, Vanessa; Hindocha, Sheena; Salles, Fabrice; Bennett, Stephen; Jones, Deborah; Jaouen, Frédéric

    2017-01-11

    Active and inexpensive catalysts for oxygen reduction are crucially needed for the widespread development of polymer electrolyte fuel cells and metal-air batteries. While iron-nitrogen-carbon materials pyrolytically prepared from ZIF-8, a specific zeolitic imidazolate framework (ZIF) with sodalite topology, have shown enhanced activities toward oxygen reduction in acidic electrolyte, the rational design of sacrificial metal-organic frameworks toward this application has hitherto remained elusive. Here, we report for the first time that the oxygen reduction activity of Fe-N-C catalysts positively correlates with the cavity size and mass-specific pore volume in pristine ZIFs. The high activity of Fe-N-C materials prepared from ZIF-8 could be rationalized, and another ZIF structure leading to even higher activity was identified. In contrast, the ORR activity is mostly unaffected by the ligand chemistry in pristine ZIFs. These structure-property relationships will help identifying novel sacrificial ZIF or porous metal-organic frameworks leading to even more active Fe-N-C catalysts. The findings are of great interest for a broader application of the class of inexpensive metal-nitrogen-carbon catalysts that have shown promising activity also for the hydrogen evolution (Co-N-C) and carbon dioxide reduction (Fe-N-C and Mn-N-C).

  12. Eye movements modulate the spatiotemporal dynamics of word processing.

    PubMed

    Temereanca, Simona; Hämäläinen, Matti S; Kuperberg, Gina R; Stufflebeam, Steve M; Halgren, Eric; Brown, Emery N

    2012-03-28

    Active reading requires coordination between frequent eye movements (saccades) and short fixations in text. Yet, the impact of saccades on word processing remains unknown, as neuroimaging studies typically employ constant eye fixation. Here we investigate eye-movement effects on word recognition processes in healthy human subjects using anatomically constrained magnetoencephalography, psychophysical measurements, and saccade detection in real time. Word recognition was slower and brain responses were reduced to words presented early versus late after saccades, suggesting an overall transient impairment of word processing after eye movements. Response reductions occurred early in visual cortices and later in language regions, where they colocalized with repetition priming effects. Qualitatively similar effects occurred when words appeared early versus late after background movement that mimicked saccades, suggesting that retinal motion contributes to postsaccadic inhibition. Further, differences in postsaccadic and background-movement effects suggest that central mechanisms also contribute to postsaccadic modulation. Together, these results suggest a complex interplay between visual and central saccadic mechanisms during reading.

  13. Differences in activation of aryl hydrocarbon receptors of white sturgeon relative to lake sturgeon are predicted by identities of key amino acids in the ligand binding domain.

    PubMed

    Doering, Jon A; Farmahin, Reza; Wiseman, Steve; Beitel, Shawn C; Kennedy, Sean W; Giesy, John P; Hecker, Markus

    2015-04-07

    Dioxin-like compounds (DLCs) are pollutants of global environmental concern. DLCs elicit their adverse outcomes through activation of the aryl hydrocarbon receptor (AhR). However, there is limited understanding of the mechanisms that result in differences in sensitivity to DLCs among different species of fishes. Understanding these mechanisms is critical for protection of the diversity of fishes exposed to DLCs, including endangered species. This study investigated specific mechanisms that drive responses of two endangered fishes, white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens) to DLCs. It determined whether differences in sensitivity to activation of AhRs (AhR1 and AhR2) can be predicted based on identities of key amino acids in the ligand binding domain (LBD). White sturgeon were 3- to 30-fold more sensitive than lake sturgeon to exposure to 5 different DLCs based on activation of AhR2. There were no differences in sensitivity between white sturgeon and lake sturgeon based on activation of AhR1. Adverse outcomes as a result of exposure to DLCs have been shown to be mediated through activation of AhR2, but not AhR1, in all fishes studied to date. This indicates that white sturgeon are likely to have greater sensitivity in vivo relative to lake sturgeon. Homology modeling and in silico mutagenesis suggests that differences in sensitivity to activation of AhR2 result from differences in key amino acids at position 388 in the LBD of AhR2 of white sturgeon (Ala-388) and lake sturgeon (Thr-388). This indicates that identities of key amino acids in the LBD of AhR2 could be predictive of both in vitro activation by DLCs and in vivo sensitivity to DLCs in these, and potentially other, fishes.

  14. Histochemical location of key enzyme activities involved in receptivity and self-incompatibility in the olive tree (Olea europaea L.).

    PubMed

    Serrano, Irene; Olmedilla, Adela

    2012-12-01

    Stigma-surface and style enzymes are important for pollen reception, selection and germination. This report deals with the histochemical location of the activity of four basic types of enzyme involved in these processes in the olive (Olea europaea L.). The detection of peroxidase, esterase and acid-phosphatase activities at the surface of the stigma provided evidence of early receptivity in olive pistils. The stigma maintained its receptivity until the arrival of pollen. Acid-phosphatase activity appeared in the style at the moment of anthesis and continued until the fertilization of the ovule. RNase activity was detected in the extracellular matrix of the styles of flowers just before pollination and became especially evident in pistils after self-pollination. This activity gradually decreased until it practically disappeared in more advanced stages. RNase activity was also detected in pollen tubes growing in pollinated pistils and appeared after in vitro germination in the presence of self-incompatible pistils. These findings suggest that RNases may well be involved in intraspecific pollen rejection in olive flowers. To the best of our knowledge this is the first time that evidence of enzyme activity in stigma receptivity and pollen selection has been described in this species.

  15. [The referral of infectious diseases is a key activity for infectious diseases departments and units, as well as for the hospital].

    PubMed

    Cisneros, José Miguel; Palomino-Nicás, Julián; Pachón-Diaz, Jerónimo

    2014-12-01

    Infectious diseases referrals (IDR) is a core activity of infectious diseases departments, and is certainly the one with the greatest potential impact on the hospital due to their cross-sectional nature, and with the emergence of a bacterial resistance and antimicrobial crisis. However, there is no standard model for IDR, no official training, and evaluation is merely descriptive. Paradoxically IDR are at risk in a health system that demands more quality and efficiency. The aim of this review is to assess what is known about IDR, its definition, key features, objectives, method, and the evaluation of results, and to suggest improvements to this key activity for the infectious diseases departments and the hospital.

  16. Statistical Laws Governing Fluctuations in Word Use from Word Birth to Word Death

    PubMed Central

    Petersen, Alexander M.; Tenenbaum, Joel; Havlin, Shlomo; Stanley, H. Eugene

    2012-01-01

    We analyze the dynamic properties of 107 words recorded in English, Spanish and Hebrew over the period 1800–2008 in order to gain insight into the coevolution of language and culture. We report language independent patterns useful as benchmarks for theoretical models of language evolution. A significantly decreasing (increasing) trend in the birth (death) rate of words indicates a recent shift in the selection laws governing word use. For new words, we observe a peak in the growth-rate fluctuations around 40 years after introduction, consistent with the typical entry time into standard dictionaries and the human generational timescale. Pronounced changes in the dynamics of language during periods of war shows that word correlations, occurring across time and between words, are largely influenced by coevolutionary social, technological, and political factors. We quantify cultural memory by analyzing the long-term correlations in the use of individual words using detrended fluctuation analysis. PMID:22423321

  17. Statistical Laws Governing Fluctuations in Word Use from Word Birth to Word Death

    NASA Astrophysics Data System (ADS)

    Petersen, Alexander M.; Tenenbaum, Joel; Havlin, Shlomo; Stanley, H. Eugene

    2012-03-01

    We analyze the dynamic properties of 107 words recorded in English, Spanish and Hebrew over the period 1800-2008 in order to gain insight into the coevolution of language and culture. We report language independent patterns useful as benchmarks for theoretical models of language evolution. A significantly decreasing (increasing) trend in the birth (death) rate of words indicates a recent shift in the selection laws governing word use. For new words, we observe a peak in the growth-rate fluctuations around 40 years after introduction, consistent with the typical entry time into standard dictionaries and the human generational timescale. Pronounced changes in the dynamics of language during periods of war shows that word correlations, occurring across time and between words, are largely influenced by coevolutionary social, technological, and political factors. We quantify cultural memory by analyzing the long-term correlations in the use of individual words using detrended fluctuation analysis.

  18. Mrs. Malaprop's Neighborhood: Using Word Errors to Reveal Neighborhood Structure

    ERIC Educational Resources Information Center

    Goldrick, Matthew; Folk, Jocelyn R.; Rapp, Brenda

    2010-01-01

    Many theories of language production and perception assume that in the normal course of processing a word, additional non-target words (lexical neighbors) become active. The properties of these neighbors can provide insight into the structure of representations and processing mechanisms in the language processing system. To infer the properties of…

  19. Neighborhood Density and Word Recognition: Effects of Phoneme Position

    ERIC Educational Resources Information Center

    Prescott, Tiffany Joyce Conyers

    2009-01-01

    There is considerable interest in how individuals process single words when they are heard. An examination of the literature reveals an interesting, yet little-explored contradiction between the assumptions underlying the neighborhood activation model (NAM) and contemporary models of word retrieval. In this study, participants listened to CVC…

  20. Sets, Subsets, and Dichotomous Keys

    ERIC Educational Resources Information Center

    Cole, E. James

    1973-01-01

    Discusses the procedures that should be observed in constructing a dichotomous key. The keying exercise described was used as a laboratory activity in a biology course for elementary education majors, however it could be used in other courses. (JR)

  1. Word length effects on novel words: evidence from eye movements.

    PubMed

    Lowell, Randy; Morris, Robin K

    2014-01-01

    The present study investigated the effects of word length on eye movement behavior during initial processing of novel words while reading. Adult skilled readers' eye movements were monitored as they read novel or known target words in sentence frames with neutral context preceding the target word. Comparable word length effects on all single-fixation measures for novel and known words suggested that both types of words were subject to similar initial encoding strategies. The impact of the absence of an existing lexical entry emerged in multiple first-pass fixation measures in the form of interactions between word length (long and short) and word type (novel and known). Specifically, readers spent significantly more first-pass time refixating long novel targets than short novel targets; however, the first-pass time spent refixating known controls did not differ as a function of length. Implications of these findings for models of eye movement control while reading, as well as for vocabulary acquisition in reading, are discussed.

  2. Novel mechanisms for superoxide-scavenging activity of human manganese superoxide dismutase determined by the K68 key acetylation site.

    PubMed

    Lu, Jiaqi; Cheng, Kuoyuan; Zhang, Bo; Xu, Huan; Cao, Yuanzhao; Guo, Fei; Feng, Xudong; Xia, Qing

    2015-08-01

    Superoxide is the primary reactive oxygen species generated in the mitochondria. Manganese superoxide dismutase (SOD2) is the major enzymatic superoxide scavenger present in the mitochondrial matrix and one of the most crucial reactive oxygen species-scavenging enzymes in the cell. SOD2 is activated by sirtuin 3 (SIRT3) through NAD(+)-dependent deacetylation. However, the exact acetylation sites of SOD2 are ambiguous and the mechanisms underlying the deacetylation-mediated SOD2 activation largely remain unknown. We are the first to characterize SOD2 mutants of the acetylation sites by investigating the relative enzymatic activity, structures, and electrostatic potential of SOD2 in this study. These SOD2 mutations affected the superoxide-scavenging activity in vitro and in HEK293T cells. The lysine 68 (K68) site is the most important acetylation site contributing to SOD2 activation and plays a role in cell survival after paraquat treatment. The molecular basis underlying the regulation of SOD2 activity by K68 was investigated in detail. Molecular dynamics simulations revealed that K68 mutations induced a conformational shift of residues located in the active center of SOD2 and altered the charge distribution on the SOD2 surface. Thus, the entry of the superoxide anion into the coordinated core of SOD2 was inhibited. Our results provide a novel mechanistic insight, whereby SOD2 acetylation affects the structure and charge distribution of SOD2, its tetramerization, and p53-SOD2 interactions of SOD2 in the mitochondria, which may play a role in nuclear-mitochondrial communication during aging.

  3. Biochemical and toxicological evaluation of nano-heparins in cell functional properties, proteasome activation and expression of key matrix molecules.

    PubMed

    Piperigkou, Zoi; Karamanou, Konstantina; Afratis, Nikolaos A; Bouris, Panagiotis; Gialeli, Chrysostomi; Belmiro, Celso L R; Pavão, Mauro S G; Vynios, Dimitrios H; Tsatsakis, Aristidis M

    2016-01-05

    The glycosaminoglycan heparin and its derivatives act strongly on blood coagulation, controlling the activity of serine protease inhibitors in plasma. Nonetheless, there is accumulating evidence highlighting different anticancer activities of these molecules in numerous types of cancer. Nano-heparins may have great biological significance since they can inhibit cell proliferation and invasion as well as inhibiting proteasome activation. Moreover, they can cause alterations in the expression of major modulators of the tumor microenvironment, regulating cancer cell behavior. In the present study, we evaluated the effects of two nano-heparin formulations: one isolated from porcine intestine and the other from the sea squirt Styela plicata, on a breast cancer cell model. We determined whether these nano-heparins are able to affect cell proliferation, apoptosis and invasion, as well as proteasome activity and the expression of extracellular matrix molecules. Specifically, we observed that nano-Styela compared to nano-Mammalian analogue has higher inhibitory role on cell proliferation, invasion and proteasome activity. Moreover, nano-Styela regulates cell apoptosis, expression of inflammatory molecules, such as IL-6 and IL-8 and reduces the expression levels of extracellular matrix macromolecules, such as the proteolytic enzymes MT1-MMP, uPA and the cell surface proteoglycans syndecan-1 and -2, but not on syndecan-4. The observations reported in the present article indicate that nano-heparins and especially ascidian heparin are effective agents for heparin-induced effects in critical cancer cell functions, providing an important possibility in pharmacological targeting.

  4. Automatic letters with Microsoft Word for Windows.

    PubMed

    Gerraty, B J

    1996-03-01

    This article offers a simple process for creating a series of separate letter formats and then automating the production of individual letters from them. These letter formats can then be assembled into various categories and displayed on a computer screen. The key concepts are: Templates, Fields, Auto Macros, Macros and Custom Dialog Boxes. This is made possible because Word for Windows allows the exploration and alteration of its basic editing commands. It has great flexibility as nothing is set in concrete: a built-in command macro may be changed and a custom macro created to replace it. This article assumes the use of Microsoft Word 6.0 and some familiarity with it. The various macros notated are 'syntax sensitive' so a full stop or comma in the wrong place, or left out, will result in the macro failing to run.

  5. Key role of the loop connecting the two beta strands of mussel defensin in its antimicrobial activity.

    PubMed

    Romestand, Bernard; Molina, Franck; Richard, Véronique; Roch, Philippe; Granier, Claude

    2003-07-01

    To elucidate the structural features of the mussel defensin MGD1 required for antimicrobial activity, we synthesized a series of peptides corresponding to the main known secondary structures of the molecule and evaluated their activity towards Gram-positive and Gram-negative bacteria, and filamentous fungi. We found that the nonapeptide corresponding to residues 25-33 of MGD1 (CGGWHRLRC) exhibited bacteriostatic activity once it was cyclized by a non-naturally occurring disulfide bridge. Longer peptides corresponding to the amino acid sequences of the alpha-helical part or to the beta-strands of MGD1 had no detectable activity. The bacteriostatic activity of the sequence 25-33 was strictly dependent on the bridging of Cys25 and Cys33 and was proportional to the theoretical isoelectric point of the peptide, as deduced from the variation of activity in a set of peptide analogues of the 25-33 sequence with different numbers of cationic charges. By using confocal fluorescence microscopy, we found that the cyclic peptides bound to Gram-positive bacteria without apparent lysis. However, by using a fluorescent dye, we observed that dead bacteria had been permeated by the cyclic peptide 25-33. Sequence comparisons in the family of arthopod defensins indicate that MGD1 belongs to a subfamily of the insect defensins, characterized by the constant occurrence of both positively charged and hydrophobic amino acids in the loop. Modelling studies showed that in the MGD1 structure, positively charged and hydrophobic residues are organized in two layered clusters, which might have a functional significance in the docking of MGD1 to the bacterial membrane.

  6. Key role of persistent free radicals in hydrogen peroxide activation by biochar: implications to organic contaminant degradation.

    PubMed

    Fang, Guodong; Gao, Juan; Liu, Cun; Dionysiou, Dionysios D; Wang, Yu; Zhou, Dongmei

    2014-01-01

    We investigated the activation of hydrogen peroxide (H2O2) by biochars (produced from pine needles, wheat, and maize straw) for 2-chlorobiphenyl (2-CB) degradation in the present study. It was found that H2O2 can be effectively activated by biochar, which produces hydroxyl radical ((•)OH) to degrade 2-CB. Furthermore, the activation mechanism was elucidated by electron paramagnetic resonance (EPR) and salicylic acid (SA) trapping techniques. The results showed that biochar contains persistent free radicals (PFRs), typically ∼ 10(18) unpaired spins/gram. Higher trapped [(•)OH] concentrations were observed with larger decreases in PFRs concentration, when H2O2 was added to biochar, indicating that PFRs were the main contributor to the formation of (•)OH. This hypothesis was supported by the linear correlations between PFRs concentration and trapped [(•)OH], as well as kobs of 2-CB degradation. The correlation coefficients (R(2)) were 0.723 and 0.668 for PFRs concentration vs trapped [(•)OH], and PFRs concentration vs kobs, respectively, when all biochars pyrolyzed at different temperatures were included. For the same biochar washed by different organic solvents (methanol, hexane, dichloromethane, and toluene), the correlation coefficients markedly increased to 0.818-0.907. Single-electron transfer from PFRs to H2O2 was a possible mechanism for H2O2 activation by biochars, which was supported by free radical quenching studies. The findings of this study provide a new pathway for biochar implication and insight into the mechanism of H2O2 activation by carbonaceous materials (e.g., activated carbon and graphite).

  7. Direct Synthesis of Protoberberine Alkaloids by Rh-Catalyzed C-H Bond Activation as the Key Step.

    PubMed

    Jayakumar, Jayachandran; Cheng, Chien-Hong

    2016-01-26

    A one-pot reaction of substituted benzaldehydes with alkyne-amines by a Rh-catalyzed C-H activation and annulation to afford various natural and unnatural protoberberine alkaloids is reported. This reaction provides a convenient route for the generation of a compound library of protoberberine salts, which recently have attracted great attention because of their diverse biological activities. In addition, pyridinium salt derivatives can also be formed in good yields from α,β-unsaturated aldehydes and amino-alkynes. This reaction proceeds with excellent regioselectivity and good functional group compatibility under mild reaction conditions by using O2 as the oxidant.

  8. Investigation of the Key Pharmacological Activities of Ficus racemosa and Analysis of Its Major Bioactive Polyphenols by HPLC-DAD

    PubMed Central

    Sumi, Salma Akter; Siraj, Md. Afjalus; Hossain, Amir; Mia, Md. Sagir; Afrin, Seagufta

    2016-01-01

    Objective. Oxidative stress leads to numerous physiological disorders including infectious diseases, inflammation, and cancer. The present study was carried out to investigate antioxidant, antibacterial, and cytotoxic activity of methanol crude extract of leaves and fruits of the Ficus racemosa (LCME and FCME, resp.) and to analyse its major bioactive polyphenols by HPLC-DAD. Methods. Antioxidant capacity of the extracts was evaluated by DPPH free radical scavenging, reducing power, total phenolic, total flavonoid, total tannin content assay, superoxide radical, hydroxyl radical, and hydrogen peroxide scavenging assay. Identification and quantification of bioactive polyphenols were done by HPLC-DAD method. Antibacterial activity was tested by “disc diffusion” method. Brine shrimp lethality assay was carried out to check the cytotoxic potential. Result. Both LCME and FCME showed DPPH scavenging ability and concentration dependent reducing power activity. They had phenolic content, flavonoid content, and tannin content. Both the extracts showed superoxide radical scavenging ability, hydroxyl radical scavenging ability, and hydrogen peroxide scavenging ability. HPLC analysis of LCME and FCME indicated the presence of significant amount of gallic acid along with other phenolic constituents. Conclusion. Significant amount of gallic acid along with other phenolic constituents might have played an important role in the observed antioxidant, antibacterial, and cytotoxic activity. PMID:28105059

  9. Testing Models: A Key Aspect to Promote Teaching Activities Related to Models and Modelling in Biology Lessons?

    ERIC Educational Resources Information Center

    Krell, Moritz; Krüger, Dirk

    2016-01-01

    This study investigated biology teachers' (N = 148) understanding of models and modelling (MoMo), their model-related teaching activities and relations between the two. A framework which distinguishes five aspects of MoMo in science ("nature of models," "multiple models," "purpose of models," "testing…

  10. The Online Interactive Curriculum Portal as One Key to the Well-Structured Learning Activity of Students.

    ERIC Educational Resources Information Center

    Lehtonen, Miika

    In contrast to traditional types of learning and teaching processes and learning media, such as printed material for Web and hypermedia learning resources, Web resources and Web-based activities are quite often unfortunately more or less separate parts of the planning process and curriculum documentation in an organization's traditional…

  11. Motivational Activities for High School Economics, Keyed to the New York State Syllabus "Economics and Economic Decision Making."

    ERIC Educational Resources Information Center

    Dawson, George G.

    This manual provides secondary school teachers with ideas for relating economics to student needs, interests, and experiences. The tentative syllabus "Economics and Economic Decision Making," designed for 12th grade social studies by the New York State Education Department in 1987, is used as a guide. Motivational activities for the 18…

  12. Macrolones Are a Novel Class of Macrolide Antibiotics Active against Key Resistant Respiratory Pathogens In Vitro and In Vivo

    PubMed Central

    Verbanac, Donatella; Padovan, Jasna; Dominis-Kramarić, Miroslava; Kelnerić, Željko; Perić, Mihaela; Banjanac, Mihailo; Ergović, Gabrijela; Simon, Nerrisa; Broskey, John; Holmes, David J.; Eraković Haber, Vesna

    2016-01-01

    As we face an alarming increase in bacterial resistance to current antibacterial chemotherapeutics, expanding the available therapeutic arsenal in the fight against resistant bacterial pathogens causing respiratory tract infections is of high importance. The antibacterial potency of macrolones, a novel class of macrolide antibiotics, against key respiratory pathogens was evaluated in vitro and in vivo. MIC values against Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Haemophilus influenzae strains sensitive to macrolide antibiotics and with defined macrolide resistance mechanisms were determined. The propensity of macrolones to induce the expression of inducible erm genes was tested by the triple-disk method and incubation in the presence of subinhibitory concentrations of compounds. In vivo efficacy was assessed in a murine model of S. pneumoniae-induced pneumonia, and pharmacokinetic (PK) profiles in mice were determined. The in vitro antibacterial profiles of macrolones were superior to those of marketed macrolide antibiotics, including the ketolide telithromycin, and the compounds did not induce the expression of inducible erm genes. They acted as typical protein synthesis inhibitors in an Escherichia coli transcription/translation assay. Macrolones were characterized by low to moderate systemic clearance, a large volume of distribution, a long half-life, and low oral bioavailability. They were highly efficacious in a murine model of pneumonia after intraperitoneal application even against an S. pneumoniae strain with constitutive resistance to macrolide-lincosamide-streptogramin B antibiotics. Macrolones are the class of macrolide antibiotics with an outstanding antibacterial profile and reasonable PK parameters resulting in good in vivo efficacy. PMID:27353268

  13. Chemical genetics unveils a key role of mitochondrial dynamics, cytochrome c release and IP3R activity in muscular dystrophy.

    PubMed

    Giacomotto, Jean; Brouilly, Nicolas; Walter, Ludivine; Mariol, Marie-Christine; Berger, Joachim; Ségalat, Laurent; Becker, Thomas S; Currie, Peter D; Gieseler, Kathrin

    2013-11-15

    Duchenne muscular dystrophy (DMD) is a neuromuscular disease caused by mutations in the dystrophin gene. The subcellular mechanisms of DMD remain poorly understood and there is currently no curative treatment available. Using a Caenorhabditis elegans model for DMD as a pharmacologic and genetic tool, we found that cyclosporine A (CsA) reduces muscle degeneration at low dose and acts, at least in part, through a mitochondrial cyclophilin D, CYN-1. We thus hypothesized that CsA acts on mitochondrial permeability modulation through cyclophilin D inhibition. Mitochondrial patterns and dynamics were analyzed, which revealed dramatic mitochondrial fragmentation not only in dystrophic nematodes, but also in a zebrafish model for DMD. This abnormal mitochondrial fragmentation occurs before any obvious sign of degeneration can be detected. Moreover, we demonstrate that blocking/delaying mitochondrial fragmentation by knocking down the fission-promoting gene drp-1 reduces muscle degeneration and improves locomotion abilities of dystrophic nematodes. Further experiments revealed that cytochrome c is involved in muscle degeneration in C. elegans and seems to act, at least in part, through an interaction with the inositol trisphosphate receptor calcium channel, ITR-1. Altogether, our findings reveal that mitochondria play a key role in the early process of muscle degeneration and may be a target of choice for the design of novel therapeutics for DMD. In addition, our results provide the first indication in the nematode that (i) mitochondrial permeability transition can occur and (ii) cytochrome c can act in cell death.

  14. Words and possible words in early language acquisition.

    PubMed

    Marchetto, Erika; Bonatti, Luca L

    2013-11-01

    In order to acquire language, infants must extract its building blocks-words-and master the rules governing their legal combinations from speech. These two problems are not independent, however: words also have internal structure. Thus, infants must extract two kinds of information from the same speech input. They must find the actual words of their language. Furthermore, they must identify its possible words, that is, the sequences of sounds that, being morphologically well formed, could be words. Here, we show that infants' sensitivity to possible words appears to be more primitive and fundamental than their ability to find actual words. We expose 12- and 18-month-old infants to an artificial language containing a conflict between statistically coherent and structurally coherent items. We show that 18-month-olds can extract possible words when the familiarization stream contains marks of segmentation, but cannot do so when the stream is continuous. Yet, they can find actual words from a continuous stream by computing statistical relationships among syllables. By contrast, 12-month-olds can find possible words when familiarized with a segmented stream, but seem unable to extract statistically coherent items from a continuous stream that contains minimal conflicts between statistical and structural information. These results suggest that sensitivity to word structure is in place earlier than the ability to analyze distributional information. The ability to compute nontrivial statistical relationships becomes fully effective relatively late in development, when infants have already acquired a considerable amount of linguistic knowledge. Thus, mechanisms for structure extraction that do not rely on extensive sampling of the input are likely to have a much larger role in language acquisition than general-purpose statistical abilities.

  15. Plastid Localization of the Key Carotenoid Enzyme Phytoene Synthase Is Altered by Isozyme, Allelic Variation, and Activity[W

    PubMed Central

    Shumskaya, Maria; Bradbury, Louis M.T.; Monaco, Regina R.; Wurtzel, Eleanore T.

    2012-01-01

    Plant carotenoids have unique physiological roles related to specific plastid suborganellar locations. Carotenoid metabolic engineering could enhance plant adaptation to climate change and improve food security and nutritional value. However, lack of fundamental knowledge on carotenoid pathway localization limits targeted engineering. Phytoene synthase (PSY), a major rate-controlling carotenoid enzyme, is represented by multiple isozymes residing at unknown plastid sites. In maize (Zea mays), the three isozymes were transiently expressed and found either in plastoglobuli or in stroma and thylakoid membranes. PSY1, with one to two residue modifications of naturally occurring functional variants, exhibited altered localization, associated with distorted plastid shape and formation of a fibril phenotype. Mutating the active site of the enzyme reversed this phenotype. Discovery of differential PSY locations, linked with activity and isozyme type, advances the engineering potential for modifying carotenoid biosynthesis. PMID:23023170

  16. How the clustering of phonological neighbors affects visual word recognition.

    PubMed

    Yates, Mark

    2013-09-01

    In recent years, a new scientific field known as network science has been emerging. Network science is concerned with understanding the structure and properties of networks. One concept that is commonly used in describing a network is how the nodes in the network cluster together. The current research applied the idea of clustering to the study of how phonological neighbors influence visual word recognition. The results of 2 experiments converge to show that words with neighbors that are highly clustered (i.e., are closely related in terms of sound) are recognized more slowly than are those having neighbors that are less clustered. This result is explained in terms of the principles of interactive activation where the interplay between phoneme and phonological word units is affected by the neighborhood structure of the word. It is argued that neighbors in more clustered neighborhoods become more active and directly compete with the target word, thereby slowing processing.

  17. The effects of exogenous hormones on rooting process and the activities of key enzymes of Malus hupehensis stem cuttings.

    PubMed

    Zhang, Wangxiang; Fan, Junjun; Tan, Qianqian; Zhao, Mingming; Zhou, Ting; Cao, Fuliang

    2017-01-01

    Malus hupehensis is an excellent Malus rootstock species, known for its strong adverse-resistance and apomixes. In the present study, stem cuttings of M. hupehensis were treated with three types of exogenous hormones, including indole acetic acid (IAA), naphthalene acetic acid (NAA), or green growth regulator (GGR). The effects and mechanisms of exogenous hormone treatment and antioxidant enzyme activity on adventitious root formation were investigated. The results showed that the apparent morphology of the adventitious root had four stages, including root pre-emergence stage (S0), early stage of root formation (S1), massive root formation stage (S2), and later stage of root formation (S3). The suitable concentrations of the three exogenous hormones, IAA, NAA and GGR, were 100 mg·L-1, 300 mg·L-1, and 300 mg·L-1, respectively. They shortened the rooting time by 25-47.4% and increased the rooting percentages of cuttings by 0.9-1.3 times, compared with that in the control. The dispersion in S0 stage was 3.6 times of that in the S1 stage after exogenous hormone application. The earlier the third critical point (P3) appeared, the shorter the rooting time and the greater the rooting percentage of the cuttings. During rhizogenesis, the activities of three antioxidant enzymes (POD, SOD, and PPO) showed an A-shaped trend. However, peak values of enzyme activity appeared at different points, which were 9 d before the P3, P3, and the fourth critical point (P4), respectively. Exogenous hormone treatment reduced the time to reach the peak value by 18 days, although the peak values of the enzymatic activities did not significantly changed. Our results suggested that exogenous hormone treatment mainly acted during the root pre-emergence stage, accelerated the synthesis of antioxidant enzymes, reduced the rooting time, and consequently promoted root formation. The three kinds of antioxidant enzymes acted on different stages of rooting.

  18. The relative protein abundance of UGT1A alternative splice variants as a key determinant of glucuronidation activity in vitro.

    PubMed

    Rouleau, Mélanie; Roberge, Joannie; Falardeau, Sarah-Ann; Villeneuve, Lyne; Guillemette, Chantal

    2013-04-01

    Alternative splicing (AS) is one of the most significant components of the functional complexity of human UDP-glucuronosyltransferase enzymes (UGTs), particularly for the UGT1A gene, which represents one of the best examples of a drug-metabolizing gene regulated by AS. Shorter UGT1A isoforms [isoform 2 (i2)] are deficient in glucuronic acid transferase activity but function as negative regulators of enzyme activity through protein-protein interaction. Their abundance, relative to active UGT1A enzymes, is expected to be a determinant of the global transferase activity of cells and tissues. Here we tested whether i2-mediated inhibition increases with greater abundance of the i2 protein relative to the isoform 1 (i1) enzyme, using the extrahepatic UGT1A7 as a model and a series of 23 human embryonic kidney 293 clonal cell lines expressing variable contents of i1 and i2 proteins. Upon normalization for i1, a significant reduction of 7-ethyl-10-hydroxycamptothecin glucuronide formation was observed for i1+i2 clones (mean of 53%) compared with the reference i1 cell line. In these clones, the i2 protein content varied greatly (38-263% relative to i1) and revealed two groups: 17 clones with i2 < i1 (60% ± 3%) and 6 clones with i2 ≥ i1 (153% ± 24%). The inhibition induced by i2 was more substantial for clones displaying i2 ≥ i1 (74.5%; P = 0.001) compared with those with i2 < i1 (45.5%). Coimmunoprecipitation supports a more substantial i1-i2 complex formation when i2 exceeds i1. We conclude that the relative abundance of regulatory i2 proteins has the potential to drastically alter the local drug metabolism in the cells, particularly when i2 surpasses the protein content of i1.

  19. Dogs motivate obese children for physical activity: key elements of a motivational theory of animal-assisted interventions

    PubMed Central

    Wohlfarth, Rainer; Mutschler, Bettina; Beetz, Andrea; Kreuser, Friederike; Korsten-Reck, Ulrike

    2013-01-01

    Background: There is empirical evidence that the presence of a companion animal can have a positive impact on performance. The available evidence can be viewed in terms of differing hypotheses that attempt to explain the mechanisms behind the positive effects. Little attention has been given to motivation as a potential mode of action with regards to human-animal interactions. First we give an overview of evidence that animals might promote motivation. Second we present a study to examine the effect of a therapy dog on exercise performance in children with obesity. Methods: Twelve children, aged 8–12 years old, were randomly assigned to two groups in a crossover design: dog-group and human confederate group. Several types of physical activities via accelerometer and subjective ratings of wellbeing, satisfaction, and motivation were assessed. Data were analyzed using analysis of variance for repeated measures on one factor. Results: The main effect of condition was significant for all performance variables. There was less passive behavior and more physical activity for all performance variables in the presence of the dog than in that of the human confederate. Between dog- and human- condition there was no difference in the subjective rating of motivation, wellbeing, or satisfaction. Discussion: The results demonstrate that the presence of a therapy dog has the potential to increase physical activity in obese children. Task performance as a declarative measure was increased by the presence of the dog in comparison to a human confederate, but self-report measures of motivation, satisfaction or wellbeing did not differ between the two conditions. Therefore, it stands to reason that a dog could trigger implicit motives which enhance motivation for activity. The results of our study indicate the potentially beneficial effect of incorporating dogs into outpatient training for obese children. PMID:24194726

  20. Neural dichotomy of word concreteness: a view from functional neuroimaging.

    PubMed

    Kumar, Uttam

    2016-02-01

    Our perception about the representation and processing of concrete and abstract concepts is based on the fact that concrete words are highly imagined and remembered faster than abstract words. In order to explain the processing differences between abstract and concrete concepts, various theories have been proposed, yet there is no unanimous consensus about its neural implication. The present study investigated the processing of concrete and abstract words during an orthography judgment task (implicit semantic processing) using functional magnetic resonance imaging to validate the involvement of the neural regions. Relative to non-words, both abstract and concrete words show activation in the regions of bilateral hemisphere previously associated with semantic processing. The common areas (conjunction analyses) observed for abstract and concrete words are bilateral inferior frontal gyrus (BA 44/45), left superior parietal (BA 7), left fusiform gyrus and bilateral middle occipital. The additional areas for abstract words were noticed in bilateral superior temporal and bilateral middle temporal region, whereas no distinct region was noticed for concrete words. This suggests that words with abstract concepts recruit additional language regions in the brain.

  1. Evidence of Semantic Clustering in Letter-Cued Word Retrieval

    PubMed Central

    Sung, Kyongje; Gordon, Barry; Yang, Sujeong; Schretlen, David J.

    2014-01-01

    Letter-cued word fluency is conceptualized as a phonemically guided word retrieval process. Accordingly, word clusters typically are defined solely by their phonemic similarity. We investigated semantic clustering in two letter-cued (P and S) word fluency task performances by 315 healthy adults, each for 1 min. Singular value decomposition (SVD) and generalized topological overlap measure (GTOM) were applied to verbal outputs to conservatively extract clusters of high frequency words. The results generally confirmed phonemic clustering. However, we also found considerable semantic/associative clusters of words (e.g., pen, pencil, and paper), and some words showed both phonemic and semantic associations within a single cluster (e.g., pair, pear, peach). We conclude that letter-cued fluency is not necessarily a purely phonemic word retrieval process. Strong automatic semantic activation mechanisms play an important role in letter-cued lexical retrieval. Theoretical conceptualizations of the word retrieval process with phonemic cues may also need to be re-examined in light of these analyses. PMID:24134125

  2. Long-range Electrostatic Complementarity Governs Substrate Recognition by Human Chymotrypsin C, a Key Regulator of Digestive Enzyme Activation*

    PubMed Central

    Batra, Jyotica; Szabó, András; Caulfield, Thomas R.; Soares, Alexei S.; Sahin-Tóth, Miklós; Radisky, Evette S.

    2013-01-01

    Human chymotrypsin C (CTRC) is a pancreatic serine protease that regulates activation and degradation of trypsinogens and procarboxypeptidases by targeting specific cleavage sites within their zymogen precursors. In cleaving these regulatory sites, which are characterized by multiple flanking acidic residues, CTRC shows substrate specificity that is distinct from that of other isoforms of chymotrypsin and elastase. Here, we report the first crystal structure of active CTRC, determined at 1.9-Å resolution, revealing the structural basis for binding specificity. The structure shows human CTRC bound to the small protein protease inhibitor eglin c, which binds in a substrate-like manner filling the S6-S5′ subsites of the substrate binding cleft. Significant binding affinity derives from burial of preferred hydrophobic residues at the P1, P4, and P2′ positions of CTRC, although acidic P2′ residues can also be accommodated by formation of an interfacial salt bridge. Acidic residues may also be specifically accommodated in the P6 position. The most unique structural feature of CTRC is a ring of intense positive electrostatic surface potential surrounding the primarily hydrophobic substrate binding site. Our results indicate that long-range electrostatic attraction toward substrates of concentrated negative charge governs substrate discrimination, which explains CTRC selectivity in regulating active digestive enzyme levels. PMID:23430245

  3. Elevated glycogen synthase kinase-3 activity in Fragile X mice: Key metabolic regulator with evidence for treatment potential

    PubMed Central

    Min, Wenzhong William; Yuskaitis, Christopher J.; Yan, Qijiang; Sikorski, Christopher; Chen, Shengqiang; Jope, Richard S.; Bauchwitz, Robert P.

    2009-01-01

    Significant advances have been made in understanding the underlying defects of and developing potential treatments for Fragile X syndrome (FXS), the most common heritable mental retardation. It has been shown that neuronal metabotropic glutamate receptor 5 (mGluR5)-mediated signaling is affected in FX animal models, with consequent alterations in activity-dependent protein translation and synaptic spine functionality. We demonstrate here that a central metabolic regulatory enzyme, glycogen synthase kinase-3 (GSK3) is present in a form indicating elevated activity in several regions of the FX mouse brain. Furthermore, we show that selective GSK3 inhibitors, as well as lithium, are able to revert mutant phenotypes of the FX mouse. Lithium, in particular, remained effective with chronic administration, although its effects were reversible even when given from birth. The combination of an mGluR5 antagonist and GSK3 inhibitors was not additive. Instead, it was discovered that mGluR5 signaling and GSK3 activation in the FX mouse are coordinately elevated, with inhibition of mGluR5 leading to inhibition of GSK3. These findings raise the possibility that GSK3 is a fundamental and central component of FXS pathology, with a substantial treatment potential. PMID:18952114

  4. Word semantics is processed even without attentional effort.

    PubMed

    Relander, Kristiina; Rämä, Pia; Kujala, Teija

    2009-08-01

    We examined the attentional modulation of semantic priming and the N400 effect for spoken words. The aim was to find out how the semantics of spoken language is processed when attention is directed to another modality (passive task), to the phonetics of spoken words (phonological task), or to the semantics of spoken words (word task). Equally strong behavioral priming effects were obtained in the phonological and the word tasks. A significant N400 effect was found in all tasks. The effect was stronger in the word and the phonological tasks than in the passive task, but there was no difference in the magnitude of the effect between the phonological and the word tasks. The latency of the N400 effect did not differ between the tasks. Although the N400 effect had a centroparietal maximum in the phonological and the word tasks, it was largest at the parietal recording sites in the passive task. The effect was more pronounced at the left than right recording sites in the phonological task, but there was no laterality effect in the other tasks. The N400 effect in the passive task indicates that semantic priming occurs even when spoken words are not actively attended. However, stronger N400 effect in the phonological and the word tasks than in the passive task suggests that controlled processes modulate the N400 effect. The finding that there were no differences in the N400 effect between the phonological and the word tasks indicates that the semantics of attended spoken words is processed regardless of whether semantic processing is relevant for task performance.

  5. Ten Important Words Plus: A Strategy for Building Word Knowledge

    ERIC Educational Resources Information Center

    Yopp, Ruth Helen; Yopp, Hallie Kay

    2007-01-01

    In this strategy, students individually select and record 10 important words on self-adhesive notes as they read a text. Then students build a group bar graph displaying their choices, write a sentence that summarizes the content, and then respond to prompts that ask them to think about words in powerful ways. Several prompts are suggested, each…

  6. Identifiable Orthographically Similar Word Primes Interfere in Visual Word Identification

    ERIC Educational Resources Information Center

    Burt, Jennifer S.

    2009-01-01

    University students participated in five experiments concerning the effects of unmasked, orthographically similar, primes on visual word recognition in the lexical decision task (LDT) and naming tasks. The modal prime-target stimulus onset asynchrony (SOA) was 350 ms. When primes were words that were orthographic neighbors of the targets, and…

  7. Word Stress in German Single-Word Reading

    ERIC Educational Resources Information Center

    Beyermann, Sandra; Penke, Martina

    2014-01-01

    This article reports a lexical-decision experiment that was conducted to investigate the impact of word stress on visual word recognition in German. Reaction-time latencies and error rates of German readers on different levels of reading proficiency (i.e., third graders and fifth graders from primary school and university students) were compared…

  8. The Saccharomyces cerevisiae Leu3 protein activates expression of GDH1, a key gene in nitrogen assimilation.

    PubMed

    Hu, Y; Cooper, T G; Kohlhaw, G B

    1995-01-01

    The Leu3 protein of Saccharomyces cerevisiae has been shown to be a transcriptional regulator of genes encoding enzymes of the branched-chain amino acid biosynthetic pathways. Leu3 binds to upstream activating sequences (UASLEU) found in the promoters of LEU1, LEU2, LEU4, ILV2, and ILV5. In vivo and in vitro studies have shown that activation by Leu3 requires the presence of alpha-isopropylmalate. In at least one case (LEU2), Leu3 actually represses basal-level transcription when alpha-isopropylmalate is absent. Following identification of a UASLEU-homologous sequence in the promoter of GDH1, the gene encoding NADP(+)-dependent glutamate dehydrogenase, we demonstrate that Leu3 specifically interacts with this UASLEU element. We then show that Leu3 is required for full activation of the GDH1 gene. First, the expression of a GDH1-lacZ fusion gene is three- to sixfold lower in a strain lacking the LEU3 gene than in an isogenic LEU3+ strain. Expression is restored to near-normal levels when the leu3 deletion cells are transformed with a LEU3-bearing plasmid. Second, a significant decrease in GDH1-lacZ expression is also seen when the UASLEU of the GDH1-lacZ construct is made nonfunctional by mutation. Third, the steady-state level of GDH1 mRNA decreases about threefold in leu3 null cells. The decrease in GDH1 expression in leu3 null cells is reflected in a diminished specific activity of NADP(+)-dependent glutamate dehydrogenase. We also demonstrate that the level of GDH1-lacZ expression correlates with the cells' ability to generate alpha-isopropylmalate and is lowest in cells unable to produce alpha-isopropylmalate. We conclude that GDH1, which plays an important role in the assimilation of ammonia in yeast cells, is, in part, activated by a Leu3-alpha-isopropylmalate complex. This conclusion suggests that Leu3 participates in transcriptional regulation beyond the branched-chain amino acid biosynthetic pathways.

  9. (Un-)expected nocturnal activity in "Diurnal" Lemur catta supports cathemerality as one of the key adaptations of the lemurid radiation.

    PubMed

    Donati, Giuseppe; Santini, Luca; Razafindramanana, Josia; Boitani, Luigi; Borgognini-Tarli, Silvana

    2013-01-01

    The ability to operate during the day and at night (i.e., cathemerality) is common among mammals but has rarely been identified in primates. Adaptive hypotheses assume that cathemerality represents a stable adaptation in primates, while nonadaptive hypotheses propose that it is the result of an evolutionary disequilibrium arising from human impacts on natural habitats. Madagascar offers a unique opportunity to study the evolution of activity patterns as there we find a monophyletic primate radiation that shows nocturnal, diurnal, and cathemeral patterns. However, when and why cathemeral activity evolved in lemurs is the subject of intense debate. Thus far, this activity pattern has been regularly observed in only three lemurid genera but the actual number of lemur species exhibiting this activity is as yet unknown. Here we show that the ring-tailed lemur, Lemur catta, a species previously considered to be diurnal, can in fact be cathemeral in the wild. In neighboring but distinct forest areas these lemurs exhibited either mainly diurnal or cathemeral activity. We found that, as in other cathemeral lemurs, activity was entrained by photoperiod and masked by nocturnal luminosity. Our results confirm the relationship between transitional eye anatomy and physiology and 24-h activity, thus supporting the adaptive scenario. Also, on the basis of the most recent strepsirrhine phylogenetic reconstruction, using parsimony criterion, our findings suggest pushing back the emergence of cathemerality to stem lemurids. Flexible activity over 24-h could thus have been one of the key adaptations of the early lemurid radiation possibly driven by Madagascar's island ecology.

  10. HrcT is a key component of the type III secretion system in Xanthomonas spp. and also regulates the expression of the key hrp transcriptional activator HrpX.

    PubMed

    Liu, Zhi-Yang; Zou, Li-Fang; Xue, Xiao-Bo; Cai, Lu-Lu; Ma, Wen-Xiu; Xiong, Li; Ji, Zhi-Yuan; Chen, Gong-You

    2014-07-01

    The type III secretion system (T3SS), encoded by hrp (hypersensitive response and pathogenicity) genes in Gram-negative phytopathogenic bacteria, delivers repertoires of T3SS effectors (T3SEs) into plant cells to trigger the hypersensitive response (HR) in nonhost or resistant-host plants and promote pathogenicity in susceptible plants. The expression of hrp genes in Xanthomonas is regulated by two key regulatory proteins, HrpG and HrpX. However, the interactions between hrp gene products in directing T3SE secretion are largely unknown. Here we demonstrated that HrcT of X. oryzae pv. oryzicola functions as a T3SS component and positively regulates the expression of hrpX. Transcription of hrcT occurs via two distinct promoters; one (T1) is with the hrpB operon and the second (T3) within hrpB7 Via either promoter T1 or T3, the defect in Hrp phenotype by hrcT deletion was corrected in the presence of hrcT only from Xanthomonas species but not from other phytopathogenic bacteria. An N-terminally truncated HrcT was able to bind the hrpX promoter and activate the expression of hrpX, supporting that HrcT is a positive regulator of hrpX. A revised model showing the regulatory interactions between HrcT, HrpX, and HrpG is proposed.

  11. Complementary hemispheric specialization for word and accent detection.

    PubMed

    Berman, Steven M; Mandelkern, Mark A; Phan, Hao; Zaidel, Eran

    2003-06-01

    When we hear a familiar word pronounced in a foreign accent, which parts of the brain identify the word and which identify the accent? Here we present converging evidence from PET blood flow, event-related scalp potentials, and behavioral responses during dichotic listening, showing homologous and complementary hemispheric specialization for word and accent detection. Accuracy of detecting target words was greater when stimuli were presented to the right ear, indicating left hemisphere specialization, with no ear advantage for detecting target accents. Detection of words also produced increased blood flow in a left frontal area associated with motor and phonetic processing, and a left temporal area associated with semantic memory. Homologous areas of the right hemisphere, together with right prefrontal and precuneus regions, showed increased blood flow during detection of accents. Separate analyses for each detection task indicated that voxels whose activity maximally correlated with accuracy were in the left hemisphere for word detection, but in the right hemisphere for accent detection. Voxels whose activity maximally correlated with inaccuracy were in the opposite hemisphere for both tasks, strengthening the interpretation that between-task differences in brain activation are related to lateralized specializations for task performance. ERP waveforms and reaction times suggested that greater left hemisphere activation during word detection preceded greater right hemisphere activation during accent detection. The results are interpreted as supporting left hemisphere specialization for extraction of the linguistic, phonetic, and semantic information contained in speech, and right hemisphere specialization for pragmatics, the social context of linguistic communication.

  12. Oxidative stress and hepatic stellate cell activation are key events in arsenic induced liver fibrosis in mice

    SciTech Connect

    Ghatak, Subhadip; Biswas, Ayan; Dhali, Gopal Krishna; Chowdhury, Abhijit; Boyer, James L.; Santra, Amal

    2011-02-15

    Arsenic is an environmental toxicant and carcinogen. Exposure to arsenic is associated with development of liver fibrosis and portal hypertension through ill defined mechanisms. We evaluated hepatic fibrogenesis after long term arsenic exposure in a murine model. BALB/c mice were exposed to arsenic by daily gavages of 6 {mu}g/gm body weight for 1 year and were evaluated for markers of hepatic oxidative stress and fibrosis, as well as pro-inflammatory, pro-apoptotic and pro-fibrogenic factors at 9 and 12 months. Hepatic NADPH oxidase activity progressively increased in arsenic exposure with concomitant development of hepatic oxidative stress. Hepatic steatosis with occasional collection of mononuclear inflammatory cells and mild portal fibrosis were the predominant liver lesion observed after 9 months of arsenic exposure, while at 12 months, the changes included mild hepatic steatosis, inflammation, necrosis and significant fibrosis in periportal areas. The pathologic changes in the liver were associated with markers of hepatic stellate cells (HSCs) activation, matrix reorganization and fibrosis including {alpha}-smooth muscle actin, transforming growth factor-{beta}1, PDGF-R{beta}, pro-inflammatory cytokines and enhanced expression of tissue inhibitor of metalloproteinase-1 and pro({alpha}) collagen type I. Moreover, pro-apoptotic protein Bax was dominantly expressed and Bcl-2 was down-regulated along with increased number of TUNEL positive hepatocytes in liver of arsenic exposed mice. Furthermore, HSCs activation due to increased hepatic oxidative stress observed after in vivo arsenic exposure was recapitulated in co-culture model of isolated HSCs and hepatocytes exposed to arsenic. These findings have implications not only for the understanding of the pathology of arsenic related liver fibrosis but also for the design of preventive strategies in chronic arsenicosis.

  13. Rooibos flavonoids inhibit the activity of key adrenal steroidogenic enzymes, modulating steroid hormone levels in H295R cells.

    PubMed

    Schloms, Lindie; Swart, Amanda C

    2014-03-24

    Major rooibos flavonoids--dihydrochalcones, aspalathin and nothofagin, flavones--orientin and vitexin, and a flavonol, rutin, were investigated to determine their influence on the activity of adrenal steroidogenic enzymes, 3β-hydroxysteroid dehydrogenase (3βHSD2) and cytochrome P450 (P450) enzymes, P450 17α-hydroxylase/17,20-lyase (CYP17A1), P450 21-hydroxylase (CYP21A2) and P450 11β-hydroxylase (CYP11B1). All the flavonoids inhibited 3βHSD2 and CYP17A1 significantly, while the inhibition of downstream enzymes, CYP21A2 and CYP11B1, was both substrate and flavonoid specific. The dihydrochalcones inhibited the activity of CYP21A2, but not that of CYP11B1. Although rutin, orientin and vitexin inhibited deoxycortisol conversion by CYP11B1 significantly, inhibition of deoxycorticosterone was <20%. These three flavonoids were unable to inhibit CYP21A2, with negligible inhibition of deoxycortisol biosynthesis only. Rooibos inhibited substrate conversion by CYP17A1 and CYP21A2, while the inhibition of other enzyme activities was <20%. In H295R cells, rutin had the greatest inhibitory effect on steroid production upon forskolin stimulation, reducing total steroid output 2.3-fold, while no effect was detected under basal conditions. Nothofagin and vitexin had a greater inhibitory effect on overall steroid production compared to aspalathin and orientin, respectively. The latter compounds contain two hydroxyl groups on the B ring, while nothofagin and vitexin contain a single hydroxyl group. In addition, all of the flavonoids are glycosylated, albeit at different positions--dihydrochalcones at C3' and flavones at C8 on ring A, while rutin, a larger molecule, has a rutinosyl moiety at C3 on ring C. Structural differences regarding the number and position of hydroxyl and glucose moieties as well as structural flexibility could indicate different mechanisms by which these flavonoids influence the activity of adrenal steroidogenic enzymes.

  14. The effects of exogenous hormones on rooting process and the activities of key enzymes of Malus hupehensis stem cuttings

    PubMed Central

    Tan, Qianqian; Zhao, Mingming; Zhou, Ting; Cao, Fuliang

    2017-01-01

    Malus hupehensis is an excellent Malus rootstock species, known for its strong adverse-resistance and apomixes. In the present study, stem cuttings of M. hupehensis were treated with three types of exogenous hormones, including indole acetic acid (IAA), naphthalene acetic acid (NAA), or green growth regulator (GGR). The effects and mechanisms of exogenous hormone treatment and antioxidant enzyme activity on adventitious root formation were investigated. The results showed that the apparent morphology of the adventitious root had four stages, including root pre-emergence stage (S0), early stage of root formation (S1), massive root formation stage (S2), and later stage of root formation (S3). The suitable concentrations of the three exogenous hormones, IAA, NAA and GGR, were 100 mg·L-1, 300 mg·L-1, and 300 mg·L-1, respectively. They shortened the rooting time by 25–47.4% and increased the rooting percentages of cuttings by 0.9–1.3 times, compared with that in the control. The dispersion in S0 stage was 3.6 times of that in the S1 stage after exogenous hormone application. The earlier the third critical point (P3) appeared, the shorter the rooting time and the greater the rooting percentage of the cuttings. During rhizogenesis, the activities of three antioxidant enzymes (POD, SOD, and PPO) showed an A-shaped trend. However, peak values of enzyme activity appeared at different points, which were 9 d before the P3, P3, and the fourth critical point (P4), respectively. Exogenous hormone treatment reduced the time to reach the peak value by 18 days, although the peak values of the enzymatic activities did not significantly changed. Our results suggested that exogenous hormone treatment mainly acted during the root pre-emergence stage, accelerated the synthesis of antioxidant enzymes, reduced the rooting time, and consequently promoted root formation. The three kinds of antioxidant enzymes acted on different stages of rooting. PMID:28231330

  15. Polarization: A Key Difference between Man-made and Natural Electromagnetic Fields, in regard to Biological Activity

    PubMed Central

    Panagopoulos, Dimitris J.; Johansson, Olle; Carlo, George L.

    2015-01-01

    In the present study we analyze the role of polarization in the biological activity of Electromagnetic Fields (EMFs)/Electromagnetic Radiation (EMR). All types of man-made EMFs/EMR - in contrast to natural EMFs/EMR - are polarized. Polarized EMFs/EMR can have increased biological activity, due to: 1) Ability to produce constructive interference effects and amplify their intensities at many locations. 2) Ability to force all charged/polar molecules and especially free ions within and around all living cells to oscillate on parallel planes and in phase with the applied polarized field. Such ionic forced-oscillations exert additive electrostatic forces on the sensors of cell membrane electro-sensitive ion channels, resulting in their irregular gating and consequent disruption of the cell’s electrochemical balance. These features render man-made EMFs/EMR more bioactive than natural non-ionizing EMFs/EMR. This explains the increasing number of biological effects discovered during the past few decades to be induced by man-made EMFs, in contrast to natural EMFs in the terrestrial environment which have always been present throughout evolution, although human exposure to the latter ones is normally of significantly higher intensities/energy and longer durations. Thus, polarization seems to be a trigger that significantly increases the probability for the initiation of biological/health effects. PMID:26456585

  16. Polarization: A Key Difference between Man-made and Natural Electromagnetic Fields, in regard to Biological Activity.

    PubMed

    Panagopoulos, Dimitris J; Johansson, Olle; Carlo, George L

    2015-10-12

    In the present study we analyze the role of polarization in the biological activity of Electromagnetic Fields (EMFs)/Electromagnetic Radiation (EMR). All types of man-made EMFs/EMR - in contrast to natural EMFs/EMR - are polarized. Polarized EMFs/EMR can have increased biological activity, due to: 1) Ability to produce constructive interference effects and amplify their intensities at many locations. 2) Ability to force all charged/polar molecules and especially free ions within and around all living cells to oscillate on parallel planes and in phase with the applied polarized field. Such ionic forced-oscillations exert additive electrostatic forces on the sensors of cell membrane electro-sensitive ion channels, resulting in their irregular gating and consequent disruption of the cell's electrochemical balance. These features render man-made EMFs/EMR more bioactive than natural non-ionizing EMFs/EMR. This explains the increasing number of biological effects discovered during the past few decades to be induced by man-made EMFs, in contrast to natural EMFs in the terrestrial environment which have always been present throughout evolution, although human exposure to the latter ones is normally of significantly higher intensities/energy and longer durations. Thus, polarization seems to be a trigger that significantly increases the probability for the initiation of biological/health effects.

  17. Words translated in sentence contexts produce repetition priming in visual word comprehension and spoken word production.

    PubMed

    Francis, Wendy S; Camacho, Alejandra; Lara, Carolina

    2014-10-01

    Previous research with words read in context at encoding showed little if any long-term repetition priming. In Experiment 1, 96 Spanish-English bilinguals translated words in isolation or in sentence contexts at encoding. At test, they translated words or named pictures corresponding to words produced at encoding and control words not previously presented. Repetition priming was reliable in all conditions, but priming effects were generally smaller for contextualized than for isolated words. Repetition priming in picture naming indicated priming from production in context. A componential analysis indicated priming from comprehension in context, but only in the less fluent language. Experiment 2 was a replication of Experiment 1 with auditory presentation of the words and sentences to be translated. Repetition priming was reliable in all conditions, but priming effects were again smaller for contextualized than for isolated words. Priming in picture naming indicated priming from production in context, but the componential analysis indicated no detectable priming for auditory comprehension. The results of the two experiments taken together suggest that repetition priming reflects the long-term learning that occurs with comprehension and production exposures to words in the context of natural language.

  18. Cooperative hydration effect causes thermal unfolding of proteins and water activity plays a key role in protein stability in solutions.

    PubMed

    Miyawaki, Osato; Dozen, Michiko; Hirota, Kaede

    2016-08-01

    The protein unfolding process observed in a narrow temperature range was clearly explained by evaluating the small difference in the enthalpy of hydrogen-bonding between amino acid residues and the hydration of amino acid residue separately. In aqueous solutions, the effect of cosolute on the protein stability is primarily dependent on water activity, aw, the role of which has been long neglected in the literature. The effect of aw on protein stability works as a power law so that a small change in aw is amplified substantially through the cooperative hydration effect. In the present approach, the role of hydrophobic interaction stands behind. This affects protein stability indirectly through the change in solution structure caused by the existence of cosolute.

  19. A key parameter on the adsorption of diluted aniline solutions with activated carbons: The surface oxygen content.

    PubMed

    Pardo, Beatrice; Ferrer, Nabí; Sempere, Julià; Gonzalez-Olmos, Rafael

    2016-11-01

    A total of 11 different commercial activated carbons (AC) with well characterized textural properties and oxygen surface content were tested as adsorbents for the removal of aniline as a target water pollutant. The maximum adsorption capacity of aniline for the studied AC was from 138.9 to 257.9 mg g(-1) at 296.15 K and it was observed to be strongly related to the textural properties of the AC, mainly with the BET surface area and the micropore volume. It was not observed any influence of the oxygen surface content of the AC on the maximum adsorption capacity. However, it was found that at low aniline aqueous concentration, the presence of oxygen surface groups plays a dominant role during the adsorption. A high concentration of oxygen surface groups, mainly carboxylic and phenolic groups, decreases the aniline adsorption regardless of the surface area of the AC.

  20. NETosis and lack of DNase activity are key factors in Echis carinatus venom-induced tissue destruction

    PubMed Central

    Katkar, Gajanan D.; Sundaram, Mahalingam S.; NaveenKumar, Somanathapura K.; Swethakumar, Basavarajaiah; Sharma, Rachana D.; Paul, Manoj; Vishalakshi, Gopalapura J.; Devaraja, Sannaningaiah; Girish, Kesturu S.; Kemparaju, Kempaiah

    2016-01-01

    Indian Echis carinatus bite causes sustained tissue destruction at the bite site. Neutrophils, the major leukocytes in the early defence process, accumulate at the bite site. Here we show that E. carinatus venom induces neutrophil extracellular trap (NET) formation. The NETs block the blood vessels and entrap the venom toxins at the injection site, promoting tissue destruction. The stability of NETs is attributed to the lack of NETs-degrading DNase activity in E. carinatus venom. In a mouse tail model, mice co-injected with venom and DNase 1, and neutropenic mice injected with the venom, do not develop NETs, venom accumulation and tissue destruction at the injected site. Strikingly, venom-induced mice tail tissue destruction is also prevented by the subsequent injection of DNase 1. Thus, our study suggests that DNase 1 treatment may have a therapeutic potential for preventing the tissue destruction caused by snake venom. PMID:27093631

  1. IGF-I activity may be a key determinant of stroke risk--a cautionary lesson for vegans.

    PubMed

    McCarty, M F

    2003-09-01

    IGF-I acts on vascular endothelium to activate nitric oxide synthase, thereby promoting vascular health; there is reason to believe that this protection is especially crucial to the cerebral vasculature, helping to ward off thrombotic strokes. IGF-I may also promote the structural integrity of cerebral arteries, thereby offering protection from hemorrhagic stroke. These considerations may help to explain why tallness is associated with low stroke risk, whereas growth hormone deficiency increases stroke risk--and why age-adjusted stroke mortality has been exceptionally high in rural Asians eating quasi-vegan diets, but has been declining steadily in Asia as diets have become progressively higher in animal products. There is good reason to suspect that low-fat vegan diets tend to down-regulate systemic IGF-I activity; this effect would be expected to increase stroke risk in vegans. Furthermore, epidemiology suggests that low serum cholesterol, and possibly also a low dietary intake of saturated fat--both characteristic of those adopting low-fat vegan diets--may also increase stroke risk. Vegans are thus well advised to adopt practical countermeasures to minimize stroke risk--the most definitive of which may be salt restriction. A high potassium intake, aerobic exercise training, whole grains, moderate alcohol consumption, low-dose aspirin, statin or policosanol therapy, green tea, and supplementation with fish oil, taurine, arginine, and B vitamins--as well as pharmacotherapy of hypertension if warranted--are other practical measures for lowering stroke risk. Although low-fat vegan diets may markedly reduce risk for coronary disease, diabetes, and many common types of cancer, an increased risk for stroke may represent an 'Achilles heel'. Nonetheless, vegans have the potential to achieve a truly exceptional 'healthspan' if they face this problem forthrightly by restricting salt intake and taking other practical measures that promote cerebrovascular health.

  2. Hydrophobic interactions as key determinants to the KCa3.1 channel closed configuration. An analysis of KCa3.1 mutants constitutively active in zero Ca2+.

    PubMed

    Garneau, Line; Klein, Hélène; Banderali, Umberto; Longpré-Lauzon, Ariane; Parent, Lucie; Sauvé, Rémy

    2009-01-02

    In this study we present evidence that residue Val282 in the S6 transmembrane segment of the calcium-activated KCa3.1 channel constitutes a key determinant of channel gating. A Gly scan of the S6 transmembrane segment first revealed that the substitutions A279G and V282G cause the channel to become constitutively active in zero Ca2+. Constitutive activity was not observed when residues extending from Cys276 to Ala286, other than Ala279 and Val282, were substituted to Gly. The accessibility of Cys engineered at Val275 deep in the channel cavity was next investigated for the ion-conducting V275C/V282G mutant and closed V275C channel in zero Ca2+ using Ag+ as probe. These experiments demonstrated that internal Ag+ ions have free access to the channel cavity independently of the channel conducting state, arguing against an activation gate located at the S6 segment C-terminal end. Experiments were also conducted where Val282 was substituted by residues differing in size and/or hydrophobicity. We found a strong correlation between constitutive activity in zero Ca2+ and the hydrophobic energy for side chain burial. Single channel recordings showed finally that constitutive activation in zero Ca2+ is better explained by a model where the channel is locked in a low conducting state with a high open probability rather than resulting from a change in the open/closed energy balance that would favor channel openings to a full conducting state in the absence of Ca2+. We conclude that hydrophobic interactions involving Val282 constitute key determinants to KCa3.1 gating by modulating the ion conducting state of the selectivity filter through an effect on the S6 transmembrane segment.

  3. Antecedents and Consequences of Words

    ERIC Educational Resources Information Center

    Catania, A. Charles

    2006-01-01

    As instances of behavior, words interact with environments. But they also interact with each other and with other kinds of behavior. Because of the interlocking nature of the contingencies into which words enter, their behavioral properties may become increasingly removed from nonverbal contingencies, and their relationship to those contingencies…

  4. Is Banara Really a Word?

    ERIC Educational Resources Information Center

    Qiao, Xiaomei; Forster, Kenneth; Witzel, Naoko

    2009-01-01

    Bowers, Davis, and Hanley (Bowers, J. S., Davis, C. J., & Hanley, D. A. (2005). "Interfering neighbours: The impact of novel word learning on the identification of visually similar words." "Cognition," 97(3), B45-B54) reported that if participants were trained to type nonwords such as "banara", subsequent semantic categorization responses to…

  5. CPT Word Processing Instructional Materials.

    ERIC Educational Resources Information Center

    Slaymaker, Josephine; Eakman, Donna

    A project to develop a student word processing manual was developed by using input from: (1) information specialists, employees, and educators; and (2) students using the manual. These instructional materials provide workbook assignments and reading for an individualized unit on CPT word processing to be used by 30 to 40 high school students per…

  6. Word Processing and Writing Behavior.

    ERIC Educational Resources Information Center

    Meeker, Michael W.

    Working with a word processor changes writers' behavior. They compose more easily, less anxiously, and more prolifically. The word processor makes them want to sit down and write and makes them feel good about their writing. It does this by encouraging prewriting and invention, by providing a sense of control and mastery over the actual writing…

  7. Never Trust Your Word Processor

    ERIC Educational Resources Information Center

    Linke, Dirk

    2009-01-01

    In this article, the author talks about the auto correction mode of word processors that leads to a number of problems and describes an example in biochemistry exams that shows how word processors can lead to mistakes in databases and in papers. The author contends that, where this system is applied, spell checking should not be left to a word…

  8. The Word Part Levels Test

    ERIC Educational Resources Information Center

    Sasao, Yosuke; Webb, Stuart

    2017-01-01

    Knowledge of English affixes plays a significant role in increasing knowledge of words. However, few attempts have been made to create a valid and reliable measure of affix knowledge. The Word Part Levels Test (WPLT) was developed to measure three aspects of affix knowledge: form (recognition of written affix forms), meaning (knowledge of affix…

  9. The Primacy of Abstract Syllables in Chinese Word Production

    PubMed Central

    Chen, Jenn-Yeu; O’Séaghdha, Pádraig G.; Chen, Train-Min

    2015-01-01

    Convergent evidence suggests that syllables play a primary and distinctive role in the phonological phase of Mandarin Chinese word production. Specifically, syllables are selected before other phonological components and thus guide subsyllabic encoding. The proximity of phonological syllables to word representations in Chinese languages ensures that they are also activated automatically by word perception. Therefore, in contrast to Indo-European languages, syllables but not necessarily subsyllabic components such as initial consonants can be perceptually primed in production. We tested this prediction in two masked-priming experiments. To isolate relevant phonological activation originating in primes, we used single character masked primes whose corresponding tones and lexical meanings always differed from those of the targets’ first morphemes. Related primes potentially activated the atonal first syllables or the first consonants of target words. To strongly engage production-specific processes, we used pictures as prompts for disyllabic target words. Facilitation relative to unrelated controls was observed only in the syllable sharing condition. If anything, sharing of initial consonants had a negative valence, perhaps indicative of competition among similar co-activated words or syllables. These findings corroborate the view that abstract syllables are the first selected, proximate phonological units in Chinese word production, and that phonemic segments play a subordinate role. PMID:26618911

  10. NLRP3 inflammasome activation by mitochondrial reactive oxygen species plays a key role in long-term cognitive impairment induced by paraquat exposure.

    PubMed

    Chen, Liuji; Na, Ren; Boldt, Erin; Ran, Qitao

    2015-09-01

    Exposure to environmental toxins such as pesticides is implicated in increasing Alzheimer's disease risk. In this study, we investigated the long-term effects of paraquat exposure on cognition of Alzheimer's disease animal model APP/PS1 mice and wild-type (WT) mice. Our results showed that APP/PS1 mice had exacerbated cognition impairment and elevated Aβ levels at 5 months after paraquat exposure, and that WT mice had cognition impairment at 5 and 16 months after paraquat exposure. In addition, increased mitochondrial oxidative stress and augmented brain inflammation were observed in both paraquat-exposed APP/PS1 mice and WT mice. Interestingly, activation of NLRP3 inflammasome, which triggers inflammation in response to mitochondrial stress, was enhanced in paraquat-exposed mice. Moreover, transgenic mice overexpressing Prdx3, a key enzyme in detoxifying mitochondrial H2O2, had suppressed NLRP3 inflammasome activation, reduced brain inflammation, and attenuated cognition impairment after paraquat exposure. Together, our results indicate that NLRP3 inflammasome activation induced by mitochondrial reactive oxygen species plays a key role in mediating paraquat-induced long-term cognition decline by elevating brain inflammation.

  11. The Nisi Fault as a key structure for understanding the active deformation of the NW Peloponnese, Greece

    NASA Astrophysics Data System (ADS)

    Zygouri, V.; Koukouvelas, I. K.; Kokkalas, S.; Xypolias, P.; Papadopoulos, G. A.

    2015-05-01

    The previously unknown Nisi Fault in NW Peloponnese was ruptured during the 2008 Movri Mountain earthquake attaining a maximum offset of 25 cm. The fault is interpreted as a branch of a flower structure above a blind strike-slip fault. We investigate the Nisi Fault seismotectonic evolution using morphotectonic analysis in order to determine whether the landscape is affected by tectonic forcing and paleoseismology to determine earthquake recurrence interval and fault slip rates. We applied several geomorphic indices, such as the asymmetry factor (AF), the stream length-gradient index (SL), the valley floor width to valley height ratio (Vf), the mountain-front sinuosity (Smf), the drainage basin shape (Bs) and the hypsometric curve (Hc), in four large drainage basins of the study area. The results show that fault-related vertical motions and the associated tilting influenced the drainage geometry and the landscape development. Values of stream-gradient indices (SL) are relatively high close to the fault trace. Mountain-front sinuosity (Smf) mean values along the fault zones range from 1.12 to 1.23. Valley floor width to valley height ratios (Vf) mean values along the studied fault range between 0.21 and 2.50. Drainage basin shape (BS) mean values along the fault range from 1.04 to 3.72. Lateral fault growth was likely achieved by propagation primarily towards north-northwestward. The paleoseismic history of the fault, investigated by a trench and 14C dating of seven samples, indicates two morphogenic earthquakes in the last 1 kyr. Therefore, we suggest that the Nisi Fault displays a slip rate on the order of 1 mm/yr and a recurrence interval ranging between 300 and 600 years. From a seismotectonic point of view, the fault is classified as high activity rate, with abundant but discontinuous geomorphic evidence of its activity. Other similar faults affecting the western Peloponnese can be envisaged with a similar procedure. Additionally, the seismic history and surface

  12. Late Quaternary reef growth history of Les Saintes submarine plateau: a key to constrain active faulting kinematics in Guadeloupe (FWI)

    NASA Astrophysics Data System (ADS)

    Leclerc, F.; Feuillet, N.; Deplus, C.; Cabioch, G.; Tapponnier, P.; LeBrun, J.; Bazin, S.; Beauducel, F.; Boudon, G.; Le Friant, A.; De Min, L.; Melezan, D.

    2012-12-01

    hazard. Joint analysis of the aftershocks sequence and the fault map provide a good image of the fault system recent activity. Finally, we deduced fault kinematics with respect to Holocene reef demise timing, and obtained a mean slip rate of several tenth of mm/yr on each fault, comparable to the slip rate of the near active Morne-Piton fault. Thus, the fault system could generate a Mw 6 earthquake every 250 yrs.

  13. Heterolytic Activation of C-H Bonds on Cr(III)-O Surface Sites Is a Key Step in Catalytic Polymerization of Ethylene and Dehydrogenation of Propane.

    PubMed

    Conley, Matthew P; Delley, Murielle F; Núñez-Zarur, Francisco; Comas-Vives, Aleix; Copéret, Christophe

    2015-06-01

    We describe the reactivity of well-defined chromium silicates toward ethylene and propane. The initial motivation for this study was to obtain a molecular understanding of the Phillips polymerization catalyst. The Phillips catalyst contains reduced chromium sites on silica and catalyzes the polymerization of ethylene without activators or a preformed Cr-C bond. Cr(II) sites are commonly proposed active sites in this catalyst. We synthesized and characterized well-defined chromium(II) silicates and found that these materials, slightly contaminated with a minor amount of Cr(III) sites, have poor polymerization activity and few active sites. In contrast, chromium(III) silicates have 1 order of magnitude higher activity. The chromium(III) silicates initiate polymerization by the activation of a C-H bond of ethylene. Density functional theory analysis of this process showed that the C-H bond activation step is heterolytic and corresponds to a σ-bond metathesis type process. The same well-defined chromium(III) silicate catalyzes the dehydrogenation of propane at elevated temperatures with activities similar to those of a related industrial chromium-based catalyst. This reaction also involves a key heterolytic C-H bond activation step similar to that described for ethylene but with a significantly higher energy barrier. The higher energy barrier is consistent with the higher pKa of the C-H bond in propane compared to the C-H bond in ethylene. In both cases, the rate-determining step is the heterolytic C-H bond activation.

  14. Uiavy sobi: uchnivs'ski zoshyt [and] vidpovidi do uchnivs'koho zoshyta (Just Imagine: Activity Book [and] Answer Key to Student Activity Book). Collage 3: A Ukrainian Language Development Series.

    ERIC Educational Resources Information Center

    Boruszczak, Bohdan, Comp.

    This workbook is one of four intermediate- to advanced-level activity books in a series for teaching the Ukrainian language to both native speakers and second language learners. It offers a selection of exercises, vocabulary builders, dialogs, and writing exercises for language skill development. A teacher's answer key to accompany the activity…

  15. Tsikave: uchnivs'ski zoshyt [and] vidpovidi do uchnivs'koho zoshyta (It's Interesting: Activity Book [and] Answer Key to Student Activity Book). Collage 3: A Ukrainian Language Development Series.

    ERIC Educational Resources Information Center

    Boruszczak, Bohdan, Comp.

    This workbook is one of four intermediate- to advanced-level activity books in a series for teaching the Ukrainian language to both native speakers and second language learners. It offers a selection of exercises, vocabulary builders, dialogs, and writing exercises for language skill development. A teacher's answer key to accompany the activity…

  16. I smikh, i plach: uchnivs'ski zoshyt [and] vidpovidi do uchnivs'koho zoshyta (Laughter and Tears: Activity Book [and] Answer Key to Student Activity Book). Collage 3: A Ukrainian Language Development Series.

    ERIC Educational Resources Information Center

    Boruszczak, Bohdan, Comp.

    This workbook is one of four intermediate- to advanced-level activity books in a series for teaching the Ukrainian language to both native speakers and second language learners. It offers a selection of exercises, vocabulary builders, dialogs, and writing exercises for language skill development. A teacher's answer key to accompany the activity…

  17. Dva shliakhy: uchnivs'ski zoshyt [and] vidpovidi do uchnivs'koho zoshyta (Two Paths: Student Activity Book [and] Answer Key to Student Activity Book). Collage 3: A Ukrainian Language Development Series.

    ERIC Educational Resources Information Center

    Boruszczak, Bohdan, Comp.

    This workbook is one of four intermediate- to advanced-level activity books in a series for teaching the Ukrainian language to both native speakers and second language learners. It offers a selection of exercises, vocabulary builders, dialogs, and writing exercises for language skill development. A teacher's answer key to accompany the activity…

  18. Modeling synchronous theta activity in the medial septum: key role of local communications between different cell populations.

    PubMed

    Mysin, Ivan E; Kitchigina, Valentina F; Kazanovich, Yakov

    2015-08-01

    It is widely believed that the theta rhythm in the hippocampus is caused by the rhythmic input from the medial septum-diagonal band of Broca (MSDB). The main MSDB output is formed by GABAergic projection neurons which are divided into two subpopulations and fire at different phases of the hippocampal theta rhythm. The MSDB also contains projection cholinergic, glutamatergic, and non-projection GABAergic neurons. These cell populations innervate each other and also GABAergic projection neurons and participate in the formation of the synchronous rhythmic output to the hippocampus. The purpose of this study is to work out a model of interactions between all neural populations of the MSDB that underlie the formation of the synchronous septal theta signal. The model is built from biologically plausible neurons of the Hodgkin-Huxley type and its architecture reflects modern data on the morphology of neural connections in the MSDB. The model satisfies the following requirements: (1) a large portion of neurons is fast-spiking; (2) the subpopulations of GABAergic projection neurons contain endogenous pacemaker neurons; (3) the phase shift of activity between subpopulations of GABAergic projection neurons is equal to about 150°; and (4) the strengths of bidirectional connections between the subpopulations of GABAergic projection cells are different. It is shown that the theta rhythm generation can be performed by a system of glutamatergic and GABAergic non-projection neurons. We also show that bursting pacemaker neurons in the subpopulation of projection GABAergic neurons play a significant role in the formation of stable antiphase outputs from the MSDB to the hippocampus.

  19. Activation/modulation of adaptive immunity emerges simultaneously after 17DD yellow fever first-time vaccination: is this the key to prevent severe adverse reactions following immunization?

    PubMed Central

    Martins, M Â; Silva, M L; Marciano, A P V; Peruhype-Magalhães, V; Eloi-Santos, S M; Ribeiro, J G L; Correa-Oliveira, R; Homma, A; Kroon, E G; Teixeira-Carvalho, A; Martins-Filho, O A

    2007-01-01

    Over past decades the 17DD yellow fever vaccine has proved to be effective in controlling yellow fever and promises to be a vaccine vector for other diseases, but the cellular and molecular mechanisms by which it elicits such broad-based immunity are still unclear. In this study we describe a detailed phenotypic investigation of major and minor peripheral blood lymphocyte subpopulations aimed at characterizing the kinetics of the adaptive immune response following primary 17DD vaccination. Our major finding is a decreased frequency of circulating CD19+ cells at day 7 followed by emerging activation/modulation phenotypic features (CD19+interleukin(IL)10R+/CD19+CD32+) at day 15. Increased frequency of CD4+human leucocyte antigen D-related(HLA-DR+) at day 7 and CD8+HLA-DR+ at day 30 suggest distinct kinetics of T cell activation, with CD4+ T cells being activated early and CD8+ T cells representing a later event following 17DD vaccination. Up-regulation of modulatory features on CD4+ and CD8+ cells at day 15 seems to be the key event leading to lower frequency of CD38+ T cells at day 30. Taken together, our findings demonstrate the co-existence of phenotypic features associated with activation events and modulatory pathways. Positive correlations between CD4+HLA-DR+ cells and CD4+CD25high regulatory T cells and the association between the type 0 chemokine receptor CCR2 and the activation status of CD4+ and CD8+ cells further support this hypothesis. We hypothesize that this controlled microenviroment seems to be the key to prevent the development of serious adverse events, and even deaths, associated with the 17DD vaccine reported in the literature. PMID:17309541

  20. We Are What We Eat! But Who Controls Our Choice? An Active Learning Project on Food & Nutrition with Activities for Key Stages 1, 2, 3, and 4.

    ERIC Educational Resources Information Center

    Jarvis, Heather

    This activity book is designed to create awareness about all the issues attached to food supply and a healthy diet with factual information. Materials are provided for teachers to teach children about food in its entirety. The nine units include: (1) "Starting Activities: Sorting Foods and Factors Which Control Our Diet"; (2) "Food Likes and…

  1. Recognition of spoken words: semantic effects in lexical access.

    PubMed

    Wurm, Lee H; Vakoch, Douglas A; Seaman, Sean R

    2004-01-01

    Until recently most models of word recognition have assumed that semantic auditory naming effects come into play only after the identification of the word in question. What little evidence exists for early semantic effects in word recognition lexical decision has relied primarily on priming manipulations using the lexical decision task, and has used visual stimulus presentation. The current study uses semantics auditory stimulus presentation and multiple experimental tasks, and does not use priming. Response latencies for 100 common nouns were found to speech perception depend on perceptual dimensions identified by Osgood (1969): Evaluation, Potency, and Activity. In addition, the two-way interactions between these word recognition dimensions were significant. All effects were above and beyond the effects of concreteness, word length, frequency, onset phoneme characteristics, stress, and neighborhood density. Results are discussed against evidence from several areas of research suggesting a role of behaviorally important information in perception.

  2. Word Generation Randomized Trial: Discussion Mediates the Impact of Program Treatment on Academic Word Learning

    ERIC Educational Resources Information Center

    Lawrence, Joshua F.; Crosson, Amy C.; Paré-Blagoev, E. Juliana; Snow, Catherine E.

    2015-01-01

    Classroom discussion, despite its association with good academic outcomes, is exceedingly rare in U.S. schools. The Word Generation intervention involves the provision of texts and activities to be implemented across content area class, organized around engaging and discussable dilemmas. The program was evaluated with 1,554 middle grade students…

  3. The Function of Words: Distinct Neural Correlates for Words Denoting Differently Manipulable Objects

    ERIC Educational Resources Information Center

    Rueschemeyer, Shirley-Ann; van Rooij, Daan; Lindemann, Oliver; Willems, Roel M.; Bekkering, Harold

    2010-01-01

    Recent research indicates that language processing relies on brain areas dedicated to perception and action. For example, processing words denoting manipulable objects has been shown to activate a fronto-parietal network involved in actual tool use. This is suggested to reflect the knowledge the subject has about how objects are moved and used.…

  4. The last words

    NASA Astrophysics Data System (ADS)

    Vasylhmas, V. M.

    Much of what I'm going to say can be subsumed under the title: the meaning of merging or reconnection. When I look back at the controversy which has surrounded the concept for the past thirty years and try to understand historically how it arose, I find it rather remarkable that there has been that much controversy. The word reconnection becomes in some cases almost an emotional symbol, and some people seem to object merely to the name. One can find papers where the concept is violently objected to, but if one examines what the author is doing, one finds he is doing essentially the same physics; he is only absolutely refusing to use that name and insisting that anyone who uses it is wrong. So I would like to, so to speak, demythologize that and discuss what it is we really talk about when we talk about reconnection or merging. Leaving aside the precise legal definitions, I think what we are talking about is very simple. It's a system with a complex magnetic topology, where we have a plasma flow in it of some sort: plasma flow in a complex topology. In the case of the earth, initially there may have been some argument as to whether the topology is really complex or whether all the field lines are just nicely contained in one volume—there was a big battle about that some 15 years ago—but today I think it's generally accepted that the magnetosphere is open; so we do have a complex topology, and of course we know that the solar wind is flowing.

  5. A Prerequisite to L1 Homophone Effects in L2 Spoken-Word Recognition

    ERIC Educational Resources Information Center

    Nakai, Satsuki; Lindsay, Shane; Ota, Mitsuhiko

    2015-01-01

    When both members of a phonemic contrast in L2 (second language) are perceptually mapped to a single phoneme in one's L1 (first language), L2 words containing a member of that contrast can spuriously activate L2 words in spoken-word recognition. For example, upon hearing cattle, Dutch speakers of English are reported to experience activation…

  6. Cognate and Word Class Ambiguity Effects in Noun and Verb Processing

    ERIC Educational Resources Information Center

    Bultena, Sybrine; Dijkstra, Ton; van Hell, Janet G.

    2013-01-01

    This study examined how noun and verb processing in bilingual visual word recognition are affected by within and between-language overlap. We investigated how word class ambiguous noun and verb cognates are processed by bilinguals, to see if co-activation of overlapping word forms between languages benefits from additional overlap within a…

  7. Not All Ambiguous Words Are Created Equal: An EEG Investigation of Homonymy and Polysemy

    ERIC Educational Resources Information Center

    Klepousniotou, Ekaterini; Pike, G. Bruce; Steinhauer, Karsten; Gracco, Vincent

    2012-01-01

    Event-related potentials (ERPs) were used to investigate the time-course of meaning activation of different types of ambiguous words. Unbalanced homonymous ("pen"), balanced homonymous ("panel"), metaphorically polysemous ("lip"), and metonymically polysemous words ("rabbit") were used in a visual single-word priming delayed lexical decision task.…

  8. Morphological Processing during Visual Word Recognition in Hebrew as a First and a Second Language

    ERIC Educational Resources Information Center

    Norman, Tal; Degani, Tamar; Peleg, Orna

    2017-01-01

    The present study examined whether sublexical morphological processing takes place during visual word-recognition in Hebrew, and whether morphological decomposition of written words depends on lexical activation of the complete word. Furthermore, it examined whether morphological processing is similar when reading Hebrew as a first language (L1)…

  9. Cross-Language Effects in Written Word Recognition: The Case of Bilingual Deaf Children

    ERIC Educational Resources Information Center

    Ormel, Ellen; Hermans, Daan; Knoors, Harry; Verhoeven, Ludo

    2012-01-01

    In recent years, multiple studies have shown that the languages of a bilingual interact during processing. We investigated sign activation as deaf children read words. In a word-picture verification task, we manipulated the underlying sign equivalents. We presented children with word-picture pairs for which the sign translation equivalents varied…

  10. The cingulo-opercular network provides word-recognition benefit.

    PubMed

    Vaden, Kenneth I; Kuchinsky, Stefanie E; Cute, Stephanie L; Ahlstrom, Jayne B; Dubno, Judy R; Eckert, Mark A

    2013-11-27

    Recognizing speech in difficult listening conditions requires considerable focus of attention that is often demonstrated by elevated activity in putative attention systems, including the cingulo-opercular network. We tested the prediction that elevated cingulo-opercular activity provides word-recognition benefit on a subsequent trial. Eighteen healthy, normal-hearing adults (10 females; aged 20-38 years) performed word recognition (120 trials) in multi-talker babble at +3 and +10 dB signal-to-noise ratios during a sparse sampling functional magnetic resonance imaging (fMRI) experiment. Blood oxygen level-dependent (BOLD) contrast was elevated in the anterior cingulate cortex, anterior insula, and frontal operculum in response to poorer speech intelligibility and response errors. These brain regions exhibited significantly greater correlated activity during word recognition compared with rest, supporting the premise that word-recognition demands increased the coherence of cingulo-opercular network activity. Consistent with an adaptive control network explanation, general linear mixed model analyses demonstrated that increased magnitude and extent of cingulo-opercular network activity was significantly associated with correct word recognition on subsequent trials. These results indicate that elevated cingulo-opercular network activity is not simply a reflection of poor performance or error but also supports word recognition in difficult listening conditions.

  11. Spoken word recognition without a TRACE

    PubMed Central

    Hannagan, Thomas; Magnuson, James S.; Grainger, Jonathan

    2013-01-01

    How do we map the rapid input of spoken language onto phonological and lexical representations over time? Attempts at psychologically-tractable computational models of spoken word recognition tend either to ignore time or to transform the temporal input into a spatial representation. TRACE, a connectionist model with broad and deep coverage of speech perception and spoken word recognition phenomena, takes the latter approach, using exclusively time-specific units at every level of representation. TRACE reduplicates featural, phonemic, and lexical inputs at every time step in a large memory trace, with rich interconnections (excitatory forward and backward connections between levels and inhibitory links within levels). As the length of the memory trace is increased, or as the phoneme and lexical inventory of the model is increased to a realistic size, this reduplication of time- (temporal position) specific units leads to a dramatic proliferation of units and connections, begging the question of whether a more efficient approach is possible. Our starting point is the observation that models of visual object recognition—including visual word recognition—have grappled with the problem of spatial invariance, and arrived at solutions other than a fully-reduplicative strategy like that of TRACE. This inspires a new model of spoken word recognition that combines time-specific phoneme representations similar to those in TRACE with higher-level representations based on string kernels: temporally independent (time invariant) diphone and lexical units. This reduces the number of necessary units and connections by several orders of magnitude relative to TRACE. Critically, we compare the new model to TRACE on a set of key phenomena, demonstrating that the new model inherits much of the behavior of TRACE and that the drastic computational savings do not come at the cost of explanatory power. PMID:24058349

  12. Talker variation and word learning

    NASA Astrophysics Data System (ADS)

    Hollich, George; Jusczyk, Peter; Brent, Michael

    2002-05-01

    While infants must go beyond talker-specific information in recognizing a given word, regardless of the talker, they must also process talker-specific information in order to extract meaning from a particular sound source. Otherwise, for example, they could never recognize whether [hct] referred to a talker's pronunciation of hot, hut, or even hat. This poster suggests that not only do infants process talker-specific information, but they also make use of it both to extract invariant properties in learning a new word and in recognizing talker-specific tokens faster. Using the splitscreen preferential looking paradigm, two studies were conducted that examined how talker-specific properties and variation among talkers could facilitate word learning. Results of study 1 indicated that word learning was facilitated in the case where infants heard different talkers. Thus, talker variation is critical for the extraction of invariant properties of a word. However, the results of study 2 indicated that talker-specific properties were encoded and used to help these infants recognize and learn the referents of these words. Given this evidence, it is suggested that infants appear to be using talker-specific information to form abstract representations of the invariant properties of words.

  13. Evidence for morphological composition in compound words using MEG

    PubMed Central

    Brooks, Teon L.; Cid de Garcia, Daniela

    2015-01-01

    Psycholinguistic and electrophysiological studies of lexical processing show convergent evidence for morpheme-based lexical access for morphologically complex words that involves early decomposition into their constituent morphemes followed by some combinatorial operation. Considering that both semantically transparent (e.g., sailboat) and semantically opaque (e.g., bootleg) compounds undergo morphological decomposition during the earlier stages of lexical processing, subsequent combinatorial operations should account for the difference in the contribution of the constituent morphemes to the meaning of these different word types. In this study we use magnetoencephalography (MEG) to pinpoint the neural bases of this combinatorial stage in English compound word recognition. MEG data were acquired while participants performed a word naming task in which three word types, transparent compounds (e.g., roadside), opaque compounds (e.g., butterfly), and morphologically simple words (e.g., brothel) were contrasted in a partial-repetition priming paradigm where the word of interest was primed by one of its constituent morphemes. Analysis of onset latency revealed shorter latencies to name compound words than simplex words when primed, further supporting a stage of morphological decomposition in lexical access. An analysis of the associated MEG activity uncovered a region of interest implicated in morphological composition, the Left Anterior Temporal Lobe (LATL). Only transparent compounds showed increased activity in this area from 250 to 470 ms. Previous studies using sentences and phrases have highlighted the role of LATL in performing computations for basic combinatorial operations. Results are in tune with decomposition models for morpheme accessibility early in processing and suggest that semantics play a role in combining the meanings of morphemes when their composition is transparent to the overall word meaning. PMID:25972798

  14. Quantitative Proteomic analysis on Activated Hepatic Stellate Cells reversion Reveal STAT1 as a key regulator between Liver Fibrosis and recovery

    PubMed Central

    Zhang, Hongyu; Chen, Fangyan; Fan, Xu; Lin, Cong; Hao, Yunwei; Wei, Handong; Lin, Weiran; Jiang, Ying; He, Fuchu

    2017-01-01

    Understanding the changes of activated HSCs reversion is an essential step toward clarifying the potential roles of HSCs in the treatment of liver fibrosis. In this study, we chose adipocyte differentiation mixture to induce LX-2 cells for 2 days in vitro as reversion phase, comparing with normal cultured LX-2 cells as activation phase. Mass spectrometric-based SILAC technology was adopted to study differentially expressed proteome of LX-2 cells between reversion and activation. Compared with activated HSCs, 273 proteins showed significant differences in reverted HSCs. The main pathway of up-regulated proteins associated with reversion of HSCs mainly related to oxidation-reduction and lipid metabolism, while the top pathway of down-regulated proteins was found in regulated cytoskeleton formation. Changes in the expression levels of selected proteins were verified by Western blotting analysis, especially STAT1, FLNA, LASP1, and NAMPT proteins. The distinct roles of STAT1 were further analyzed between activated and reverted of HSCs, it was found that STAT1 could affect cell proliferation of HSCs and could be viewed as a key regulator in the reversion of HSCs. Thus, the proteomic analysis could accelerate our understanding of the mechanisms of HSC reversion on cessation of fibrogenic stimuli and provide new targets for antifibrotic liver therapy. PMID:28322315

  15. Progress, opportunities, and key fields for groundwater quality research under the impacts of human activities in China with a special focus on western China.

    PubMed

    Li, Peiyue; Tian, Rui; Xue, Chenyang; Wu, Jianhua

    2017-03-10

    Groundwater quality research is extremely important for supporting the safety of the water supply and human health in arid and semi-arid areas of China. This review article was constructed to report the latest research progress of groundwater quality in western China where groundwater quality is undergoing fast deterioration because of fast economic development and extensive anthropogenic activities. The opportunities brought by increasing public awareness of groundwater quality protection were also highlighted and discussed. To guide and promote further development of groundwater quality research in China, especially in western China, ten key groundwater quality research fields were proposed. The review shows that the intensification of human activities and the associated impacts on groundwater quality in China, especially in western China, has made groundwater quality research increasingly important, and has caught the attention of local, national, and international agencies and scholars. China has achieved some progress in groundwater quality research in terms of national and regional laws, regulations, and financial supports. The future of groundwater quality research in China, especially in western China, is promising reflected by the opportunities highlighted. The key research fields proposed in this article may also inform groundwater quality protection and management at the national and international level.

  16. Structural characterization of native autoinducing peptides and abiotic analogues reveals key features essential for activation and inhibition of an AgrC quorum sensing receptor in Staphylococcus aureus.

    PubMed

    Tal-Gan, Yftah; Ivancic, Monika; Cornilescu, Gabriel; Cornilescu, Claudia C; Blackwell, Helen E

    2013-12-11

    Staphylococcus aureus is a major human pathogen that uses quorum sensing (QS) to control virulence. Its QS system is regulated by macrocyclic peptide signals (or autoinducing peptides (AIPs)) and their cognate transmembrane receptors (AgrCs). Four different specificity groups of S. aureus have been identified to date (groups I-IV), each of which uses a different AIP:AgrC pair. Non-native ligands capable of intercepting AIP:AgrC binding, and thereby QS, in S. aureus have attracted considerable interest as chemical tools to study QS pathways and as possible antivirulence strategies for the treatment of infection. We recently reported a set of analogues of the group-III AIP that are capable of strongly modulating the activity of all four AgrC receptors. Critical to the further development of such ligands is a detailed understanding of the structural features of both native AIPs and non-native analogues that are essential for activity. Herein, we report the first three-dimensional structural analysis of the known native AIP signals (AIPs-I-IV) and several AIP-III analogues with varied biological activities using NMR spectroscopy. Integration of these NMR studies with the known agonism and antagonism profiles of these peptides in AgrC-III revealed two key structural elements that control AIP-III (and non-native peptide) activity: (1) a tri-residue hydrophobic "knob" essential for both activation and inhibition and (2) a fourth anchor point on the exocyclic tail needed for receptor activation. These results provide strong structural support for a mechanism of AIP-mediated AgrC activation and inhibition in S. aureus , and should facilitate the design of new AgrC ligands with enhanced activities (as agonists or antagonists) and simplified chemical structures.

  17. Identification of key functional residues in the active site of human {beta}1,4-galactosyltransferase 7: a major enzyme in the glycosaminoglycan synthesis pathway.

    PubMed

    Talhaoui, Ibtissam; Bui, Catherine; Oriol, Rafael; Mulliert, Guillermo; Gulberti, Sandrine; Netter, Patrick; Coughtrie, Michael W H; Ouzzine, Mohamed; Fournel-Gigleux, Sylvie

    2010-11-26

    Glycosaminoglycans (GAGs) play a central role in many pathophysiological events, and exogenous xyloside substrates of β1,4-galactosyltransferase 7 (β4GalT7), a major enzyme of GAG biosynthesis, have interesting biomedical applications. To predict functional peptide regions important for substrate binding and activity of human β4GalT7, we conducted a phylogenetic analysis of the β1,4-galactosyltransferase family and generated a molecular model using the x-ray structure of Drosophila β4GalT7-UDP as template. Two evolutionary conserved motifs, (163)DVD(165) and (221)FWGWGREDDE(230), are central in the organization of the enzyme active site. This model was challenged by systematic engineering of point mutations, combined with in vitro and ex vivo functional assays. Investigation of the kinetic properties of purified recombinant wild-type β4GalT7 and selected mutants identified Trp(224) as a key residue governing both donor and acceptor substrate binding. Our results also suggested the involvement of the canonical carboxylate residue Asp(228) acting as general base in the reaction catalyzed by human β4GalT7. Importantly, ex vivo functional tests demonstrated that regulation of GAG synthesis is highly responsive to modification of these key active site amino acids. Interestingly, engineering mutants at position 224 allowed us to modify the affinity and to modulate the specificity of human β4GalT7 toward UDP-sugars and xyloside acceptors. Furthermore, the W224H mutant was able to sustain decorin GAG chain substitution but not GAG synthesis from exogenously added xyloside. Altogether, this study provides novel insight into human β4GalT7 active site functional domains, allowing manipulation of this enzyme critical for the regulation of GAG synthesis. A better understanding of the mechanism underlying GAG assembly paves the way toward GAG-based therapeutics.

  18. Exogenous ceramide-1-phosphate (C1P) and phospho-ceramide analogue-1 (PCERA-1) regulate key macrophage activities via distinct receptors

    PubMed Central

    Katz, Sebastián; Ernst, Orna; Avni, Dorit; Athamna, Muhammad; Philosoph, Amir; Arana, Lide; Ouro, Alberto; Hoeferlin, L. Alexis; Meijler, Michael M.; Chalfant, Charles E.; Gómez-Muñoz, Antonio; Zor, Tsaffrir

    2016-01-01

    Inflammation is an ensemble of tightly regulated steps, in which macrophages play an essential role. Previous reports showed that the natural sphingolipid ceramide 1-phosphate (C1P) stimulates macrophages migration, while the synthetic C1P mimic, phospho-ceramide analogue-1 (PCERA-1), suppresses production of the key pro-inflammatory cytokine TNFα and amplifies production of the key anti-inflammatory cytokine IL-10 in LPS-stimulated macrophages, via one or more unidentified G-protein coupled receptors. We show that C1P stimulated RAW264.7 macrophages migration via the NFκB pathway and MCP-1 induction, while PCERA-1 neither mimicked nor antagonized these activities. Conversely, PCERA-1 synergistically elevated LPS-dependent IL-10 expression in RAW264.7 macrophages via the cAMP-PKA-CREB signaling pathway, while C1P neither mimicked nor antagonized these activities. Interestingly, both compounds have the capacity to additively inhibit TNFα secretion; PCERA-1, but not C1P, suppressed LPS-induced TNFα expression in macrophages in a CREB-dependent manner, while C1P, but not PCERA-1, directly inhibited recombinant TNFα converting enzyme (TACE). Finally, PCERA-1 failed to interfere with binding of C1P to either the cell surface receptor or to TACE. These results thus indicate that the natural sphingolipid C1P and its synthetic analog PCERA-1 bind and activate distinct receptors expressed in RAW264.7 macrophages. Identification of these receptors will be instrumental for elucidation of novel activities of extra-cellular sphingolipids, and may pave the way for the design of new sphingolipid mimics for the treatment of inflammatory diseases, and pathologies which depend on cell migration, as in metastatic tumors. PMID:26656944

  19. Serial order in word form retrieval: New insights from the auditory picture-word interference task.

    PubMed

    Wilshire, Carolyn; Singh, Sunita; Tattersall, Catherine

    2016-02-01

    One important theoretical question about word production concerns whether the phonemes of a word are retrieved in parallel or in sequential order. To address this question, Meyer and Schriefers (Journal of Experimental Psychology: Learning, Memory, and Cognition 17:1146-1160, 1991) used an auditory picture-word interference task and manipulated the position of the phonemes shared between a distractor word and a target picture. They found that begin-related distractors (e.g., boat-bone) facilitated naming times when they were presented within 150 ms before or after the picture, whereas end-related distractors (e.g., cone-bone) were effective only if presented within 150 ms after the picture. This suggested that the word's end phonemes were activated later than the beginning ones. However, it remained unclear whether these effects genuinely reflected facilitation at the level of phonological retrieval. In this study, we examined later distractor presentation onsets, so that the distractors had little opportunity to influence earlier, lexical selection processes. At the latest onset tested, end-related-but not begin-related-distractors significantly facilitated naming. We concluded that late-presented distractors do indeed influence phonological encoding, and that their asymmetric effects support a sequential model of phoneme retrieval.

  20. 'Winner-take-all' competition among real and illusory words.

    PubMed

    Niedeggen, Michael; Heil, Martin; Harris, Catherine L

    2006-04-03

    'Winner-take-all' networks are an important theoretical construct in visual neuroscience. An implication of winner-take-all networks is that a stimulus that wins the competition for selection receives maximal activation and will be consciously perceived, even when selection was incorrect. In this study, competition was induced between physically presented ('real') and self-constructed ('illusory') words. Semantic activation was probed by recording event-related potential responses to a downstream target word. The results showed that only words reported by participants triggered a spread of activation in the semantic system, whereas non-reported words failed to prime the target. Both effects were independent of whether the potential primes were 'real' or 'illusory'. Our findings indicate that neural 'winner-take-all' networks extend to the processing of lexical units.

  1. Developmental differences in the influence of phonological similarity on spoken word processing in Mandarin Chinese.

    PubMed

    Malins, Jeffrey G; Gao, Danqi; Tao, Ran; Booth, James R; Shu, Hua; Joanisse, Marc F; Liu, Li; Desroches, Amy S

    2014-11-01

    The developmental trajectory of spoken word recognition has been well established in Indo-European languages, but to date remains poorly characterized in Mandarin Chinese. In this study, typically developing children (N=17; mean age 10; 5) and adults (N=17; mean age 24) performed a picture-word matching task in Mandarin while we recorded ERPs. Mismatches diverged from expectations in different components of the Mandarin syllable; namely, word-initial phonemes, word-final phonemes, and tone. By comparing responses to different mismatch types, we uncovered evidence suggesting that both children and adults process words incrementally. However, we also observed key developmental differences in how subjects treated onset and rime mismatches. This was taken as evidence for a stronger influence of top-down processing on spoken word recognition in adults compared to children. This work therefore offers an important developmental component to theories of Mandarin spoken word recognition.

  2. Developing and Validating Sets of Algebra Word Problems.

    ERIC Educational Resources Information Center

    Nasser, Ramzi; Carifio, James

    The validation of key contextual features of algebra word problems was studied in two phases. In the first phase, five experts were asked to assess the appropriateness of the concepts in the problems and the adequacy of the assignment of the contextual features to the problems. In the second phase, construct validity was established by having 6…

  3. Word Processors and Invention in Technical Writing.

    ERIC Educational Resources Information Center

    Barker, Thomas T.

    1989-01-01

    Explores how word processing affects thinking and writing. Examines two myths surrounding word processors and invention in technical writing. Describes how word processing can enhance invention through collaborative writing, templates, and on-screen outlining. (MM)

  4. Hydathode trichomes actively secreting water from leaves play a key role in the physiology and evolution of root-parasitic rhinanthoid Orobanchaceae

    PubMed Central

    Světlíková, Petra; Hájek, Tomáš; Těšitel, Jakub

    2015-01-01

    Background and Aims Root hemiparasites from the rhinanthoid clade of Orobanchaceae possess metabolically active glandular trichomes that have been suggested to function as hydathode trichomes actively secreting water, a process that may facilitate resource acquisition from the host plant’s root xylem. However, no direct evidence relating the trichomes to water secretion exists, and carbon budgets associated with this energy-demanding process have not been determined. Methods Macro- and microscopic observations of the leaves of hemiparasitic Rhinanthus alectorolophus were conducted and night-time gas exchange was measured. Correlations were examined among the intensity of guttation, respiration and transpiration, and analysis of these correlations allowed the carbon budget of the trichome activity to be quantified. We examined the intensity of guttation, respiration and transpiration, correlations among which indicate active water secretion. Key Results Guttation was observed on the leaves of 50 % of the young, non-flowering plants that were examined, and microscopic observations revealed water secretion from the glandular trichomes present on the abaxial leaf side. Night-time rates of respiration and transpiration and the presence of guttation drops were positively correlated, which is a clear indicator of hydathode trichome activity. Subsequent physiological measurements on older, flowering plants indicated neither intense guttation nor the presence of correlations, which suggests that the peak activity of hydathodes is in the juvenile stage. Conclusions This study provides the first unequivocal evidence for the physiological role of the hydathode trichomes in active water secretion in the rhinanthoid Orobanchaceae. Depending on the concentration of organic elements calculated to be in the host xylem sap, the direct effect of water secretion on carbon balance ranges from close to neutral to positive. However, it is likely to be positive in the xylem-only feeding

  5. Zinc-finger protein 91 plays a key role in LIGHT-induced activation of non-canonical NF-{kappa}B pathway

    SciTech Connect

    Jin, Hong Ri; Jin, Xuejun; Lee, Jung Joon

    2010-10-01

    Research highlights: {yields} LIGHT induces ZFP91expression and nuclear translocation of p65, p52, and RelB in LT{beta}R signaling. {yields} ZFP91 knock-down abolishes DNA-binding activity of p52 and RelB but not of p65. {yields} ZFP91 regulates LIGHT-induced stabilization and activation of NIK. {yields} ZFP91 is required for the expression of non-canonical NF-{kappa}B target genes. -- Abstract: LIGHT is a member of tumor necrosis factor (TNF) superfamily, and its function is mediated through lymphotoxin-{beta} receptor (LT{beta}R), which is known to play important roles in inflammatory and immune responses through activation of NF-{kappa}B signaling pathways. However, molecular mechanism of LT{beta}R ligation-induced NF-{kappa}B signaling remains incompletely understood. In this report we demonstrate that a novel zinc-finger protein 91 (ZFP91) is a critical regulator in LIGHT-induced activation of non-canonical NF-{kappa}B pathway. ZFP91 appears to be required for NF-{kappa}B2 (p100) processing to p52, nuclear translocation of p52 and RelB, and DNA-binding activity of NF-{kappa}B in LIGHT-induced activation of non-canonical NF-{kappa}B pathway. Furthermore, ZFP91 knock-down by RNA interference blocks the LIGHT-induced accumulation of NIK and p100 processing, as well as the expression of non-canonical NF-{kappa}B target genes. These data clearly indicate that ZFP91 is a key regulator in LIGHT-induced activation of non-canonical NF-{kappa}B pathway in LT{beta}R signaling.

  6. Word-Superiority Effect as a Function of Semantic Transparency of Chinese Bimorphemic Compound Words

    ERIC Educational Resources Information Center

    Mok, Leh Woon

    2009-01-01

    The word-superiority effect (WSE) describes the superior recognition of word constituents in a word, as opposed to a non-word, context. In this study, the WSE was used as a diagnostic tool to examine the modulatory effect of word semantic transparency on the degree to which Chinese bimorphemic compound words are lexically represented as unitised…

  7. RIP1 kinase activity is dispensable for normal development but is a key regulator of inflammation in SHARPIN-deficient mice

    PubMed Central

    Berger, Scott B.; Kasparcova, Viera; Hoffman, Sandy; Swift, Barb; Dare, Lauren; Schaeffer, Michelle; Capriotti, Carol; Cook, Michael; Finger, Joshua; Hughes-Earle, Angela; Harris, Philip A.; Kaiser, William J.; Mocarski, Edward S.; Bertin, John; Gough, Peter J.

    2014-01-01

    RIP1 kinase is a key regulator of TNF-induced NFκB activation, apoptosis and necroptosis through its kinase and scaffolding activities. Dissecting the balance of RIP1 kinase activity and scaffolding function in vivo during development and TNF-dependent inflammation has been hampered by the perinatal lethality of RIP1-deficient mice. Here we generated RIP1 kinase-dead (Ripk1K45A) mice and showed they are viable and healthy, indicating that kinase activity of RIP1, but not its scaffolding function, is dispensable for viability and homeostasis. After validating that the Ripk1K45A mice were specifically protected against necroptotic stimuli in vitro and in vivo, we crossed these mice to SHARPIN-deficient cpdm mice, which develop severe skin and multi-organ inflammation that has been hypothesized to be mediated by TNF-dependent apoptosis and/or necroptosis. Remarkably, crossing Ripk1K45A mice to the cpdm strain protected against all cpdm-related pathology. Together, these data suggest that RIP1 kinase represents an attractive therapeutic target for TNF-driven inflammatory diseases. PMID:24821972

  8. Building Technologies Program Key Activities

    SciTech Connect

    2011-12-15

    The Building Technologies Program (BTP) employs a balanced approach to making buildings more energy efficient. The three pillars of our program, research and development (R&D), market stimulation, and building and equipment standards, help meet our strategic vision.

  9. Phonemic carryover perseveration: word blends.

    PubMed

    Buckingham, Hugh W; Christman, Sarah S

    2004-11-01

    This article will outline and describe the aphasic disorder of recurrent perseveration and will demonstrate how it interacts with the retrieval and production of spoken words in the language of fluent aphasic patients who have sustained damage to the left (dominant) posterior temporoparietal lobe. We will concentrate on the various kinds of sublexical segmental perseverations (the so-called phonemic carryovers of Santo Pietro and Rigrodsky) that most often play a role in the generation of word blendings. We will show how perseverative blends allow the clinician to better understand the dynamics of word and syllable production in fluent aphasia by scrutinizing the "onset/rime" and "onset/superrime" constituents of monosyllabic and polysyllabic words, respectively. We will demonstrate to the speech language pathologist the importance of the trochee stress pattern and the possibility that its metrical template may constitute a structural unit that can be perseverated.

  10. Word Processing and Teacher Evaluation.

    ERIC Educational Resources Information Center

    Pennington, J. R.

    1984-01-01

    Describes the utilization of a word processing program by a school administrator to do teacher evaluations. The discussion includes what the administrator's needs were and the physical process of setting up the system. (MBR)

  11. Acquiring a Single New Word.

    ERIC Educational Resources Information Center

    Carey, Susan; Bartlett, Elsa

    Twenty children aged 3;0 to 3;10 were studied for behavior related to the acquisition of a single new word ("chromium," which was presented as designating the color olive green). The research was conducted in three cycles: prior to exposure to "chromium," at the time of a single encounter with that word, and about a week after the first encounter.…

  12. Simple and robust determination of the activity signature of key carbohydrate metabolism enzymes for physiological phenotyping in model and crop plants.

    PubMed

    Jammer, Alexandra; Gasperl, Anna; Luschin-Ebengreuth, Nora; Heyneke, Elmien; Chu, Hyosub; Cantero-Navarro, Elena; Großkinsky, Dominik K; Albacete, Alfonso A; Stabentheiner, Edith; Franzaring, Jürgen; Fangmeier, Andreas; van der Graaff, Eric; Roitsch, Thomas

    2015-09-01

    The analysis of physiological parameters is important to understand the link between plant phenotypes and their genetic bases, and therefore is needed as an important element in the analysis of model and crop plants. The activities of enzymes involved in primary carbohydrate metabolism have been shown to be strongly associated with growth performance, crop yield, and quality, as well as stress responses. A simple, fast, and cost-effective method to determine activities for 13 key enzymes involved in carbohydrate metabolism has been established, mainly based on coupled spectrophotometric kinetic assays. The comparison of extraction buffers and requirement for dialysis of crude protein extracts resulted in a universal protein extraction protocol, suitable for the preparation of protein extracts from different organs of various species. Individual published kinetic activity assays were optimized and adapted for a semi-high-throughput 96-well assay format. These assays proved to be robust and are thus suitable for physiological phenotyping, enabling the characterization and diagnosis of the physiological state. The potential of the determination of distinct enzyme activity signatures as part of a physiological fingerprint was shown for various organs and tissues from three monocot and five dicot model and crop species, including two case studies with external stimuli. Differential and specific enzyme activity signatures are apparent during inflorescence development and upon in vitro cold treatment of young inflorescences in the monocot ryegrass, related to conditions for doubled haploid formation. Likewise, treatment of dicot spring oilseed rape with elevated CO2 concentration resulted in distinct patterns of enzyme activity responses in leaves.

  13. Prolactin increases the synthesis of 7alpha-hydroxypregnenolone, a key factor for induction of locomotor activity, in breeding male Newts.

    PubMed

    Haraguchi, Shogo; Koyama, Teppei; Hasunuma, Itaru; Vaudry, Hubert; Tsutsui, Kazuyoshi

    2010-05-01

    We recently found that the Japanese red-bellied newt, Cynops pyrrhogaster, actively produces 7alpha-hydroxypregnenolone, a previously undescribed amphibian neurosteroid. 7alpha-Hydroxypregnenolone stimulates locomotor activity of male newts. Locomotor activity of male newts increases during the breeding period as in other wild animals, but the molecular mechanism for such a change in locomotor activity is poorly understood. Here we show that the adenohypophyseal hormone prolactin (PRL) stimulates 7alpha-hydroxypregnenolone synthesis in the brain, thus increasing locomotor activity of breeding male newts. In this study, cytochrome P450(7alpha) (CYP7B), a steroidogenic enzyme catalyzing the formation of 7alpha-hydroxypregnenolone, was first identified to analyze seasonal changes in 7alpha-hydroxypregnenolone synthesis. Only males exhibited marked seasonal changes in 7alpha-hydroxypregnenolone synthesis and CYP7B expression in the brain, with a maximum level in the spring breeding period when locomotor activity of males increases. Subsequently we identified PRL as a key component of the mechanism regulating 7alpha-hydroxypregnenolone synthesis. Hypophysectomy decreased 7alpha-hydroxypregnenolone synthesis in the male brain, whereas administration of PRL but not gonadotropins to hypophysectomized males caused a dose-dependent increase in 7alpha-hydroxypregnenolone synthesis. To analyze the mode of PRL action, CYP7B and the receptor for PRL were localized in the male brain. PRL receptor was expressed in the neurons expressing CYP7B in the magnocellular preoptic nucleus. Thus, PRL appears to act directly on neurosteroidogenic magnocellular preoptic nucleus neurons to regulate 7alpha-hydroxypregnenolone synthesis, thus inducing seasonal locomotor changes in male newts. This is the first report describing the regulation of neurosteroidogenesis in the brain by an adenohypophyseal hormone in any vertebrate.

  14. Emotion and attention in visual word processing: an ERP study.

    PubMed

    Kissler, Johanna; Herbert, Cornelia; Winkler, Irene; Junghofer, Markus

    2009-01-01

    Emotional words are preferentially processed during silent reading. Here, we investigate to what extent different components of the visual evoked potential, namely the P1, N1, the early posterior negativity (EPN, around 250 ms after word onset) as well as the late positive complex (LPC, around 500 ms) respond differentially to emotional words and whether this response depends on the availability of attentional resources. Subjects viewed random sequences of pleasant, neutral and unpleasant adjectives and nouns. They were first instructed to simply read the words and then to count either adjectives or nouns. No consistent effects emerged for the P1 and N1. However, during both reading and counting the EPN was enhanced for emotionally arousing words (pleasant and unpleasant), regardless of whether the word belonged to a target or a non-target category. A task effect on the EPN was restricted to adjectives, but the effect did not interact with emotional content. The later centro-parietal LPC (450-650 ms) showed a large enhancement for the attended word class. A small and topographically distinct emotion-LPC effect was found specifically in response to pleasant words, both during silent reading and the active task. Thus, emotional word content is processed effortlessly and automatically and is not subject to interference from a primary grammatical decision task. The results are in line with other reports of early automatic semantic processing as reflected by posterior negativities in the ERP around 250 ms after word onset. Implications for models of emotion-attention interactions in the brain are discussed.

  15. Contextualising Higher Education Assessment Task Words with an "'Anti'-Glossary" Approach

    ERIC Educational Resources Information Center

    Richards, Kendall; Pilcher, Nick

    2014-01-01

    Key "generic" assessment task words such as "discuss" and "critically evaluate" are integral to higher education assessment. Although sources such as study skills guides give generic decontextualised glossaries of these words, much research rightly argues for greater dialogue between students (particularly…

  16. Acquired Affective Associations Induce Emotion Effects in Word Recognition: An ERP Study

    ERIC Educational Resources Information Center

    Fritsch, Nathalie; Kuchinke, Lars

    2013-01-01

    The present study examined how contextual learning and in particular emotionality conditioning impacts the neural processing of words, as possible key factors for the acquisition of words' emotional connotation. 21 participants learned on five consecutive days associations between meaningless pseudowords and unpleasant or neutral pictures using an…

  17. What's in a Word? Morphological Awareness and Vocabulary Knowledge in Three Languages

    ERIC Educational Resources Information Center

    McBride-Chang, Catherine; Tardif, Twila; Cho, Jeung-Ryeul; Shu, Hua; Fletcher, Paul; Stokes, Stephanie F.; Wong, Anita; Leung, Kawai

    2008-01-01

    Understanding how words are created is potentially a key component to being able to learn and understand new vocabulary words. However, research on morphological awareness is relatively rare. In this study, over 660 preschool-aged children from three language groups (Cantonese, Mandarin, and Korean speakers) in which compounding morphology is…

  18. The Princeton Review: Word Smart--Building an Educated Vocabulary. Revised Edition.

    ERIC Educational Resources Information Center

    Robinson, Adam; And Others

    Based on the idea that knowing which words to use and how to use them are keys to an individual's getting the most from his or her mind, this book aims to improve people's vocabularies. To find out which words should be known, research into the vocabularies of educated adults was conducted by "The Princeton Review." Newspapers from…

  19. Stroop effects from newly learned color words: effects of memory consolidation and episodic context.

    PubMed

    Geukes, Sebastian; Gaskell, M Gareth; Zwitserlood, Pienie

    2015-01-01

    The Stroop task is an excellent tool to test whether reading a word automatically activates its associated meaning, and it has been widely used in mono- and bilingual contexts. Despite of its ubiquity, the task has not yet been employed to test the automaticity of recently established word-concept links in novel-word-learning studies, under strict experimental control of learning and testing conditions. In three experiments, we thus paired novel words with native language (German) color words via lexical association and subsequently tested these words in a manual version of the Stroop task. Two crucial findings emerged: When novel word Stroop trials appeared intermixed among native-word trials, the novel-word Stroop effect was observed immediately after the learning phase. If no native color words were present in a Stroop block, the novel-word Stroop effect only emerged 24 h later. These results suggest that the automatic availability of a novel word's meaning depends either on supportive context from the learning episode and/or on sufficient time for memory consolidation. We discuss how these results can be reconciled with the complementary learning systems account of word learning.

  20. Recognition memory for Braille or spoken words: an fMRI study in early blind.

    PubMed

    Burton, Harold; Sinclair, Robert J; Agato, Alvin

    2012-02-15

    We examined cortical activity in early blind during word recognition memory. Nine participants were blind at birth and one by 1.5years. In an event-related design, we studied blood oxygen level-dependent responses to studied ("old") compared to novel ("new") words. Presentation mode was in Braille or spoken. Responses were larger for identified "new" words read with Braille in bilateral lower and higher tier visual areas and primary somatosensory cortex. Responses to spoken "new" words were larger in bilateral primary and accessory auditory cortex. Auditory cortex was unresponsive to Braille words and occipital cortex responded to spoken words but not differentially with "old"/"new" recognition. Left dorsolateral prefrontal cortex had larger responses to "old" words only with Braille. Larger occipital cortex responses to "new" Braille words suggested verbal memory based on the mechanism of recollection. A previous report in sighted noted larger responses for "new" words studied in association with pictures that created a distinctiveness heuristic source factor which enhanced recollection during remembering. Prior behavioral studies in early blind noted an exceptional ability to recall words. Utilization of this skill by participants in the current study possibly engendered recollection that augmented remembering "old" words. A larger response when identifying "new" words possibly resulted from exhaustive recollecting the sensory properties of "old" words in modality appropriate sensory cortices. The uniqueness of a memory role for occipital cortex is in its cross-modal responses to coding tactile properties of Braille. The latter possibly reflects a "sensory echo" that aids recollection.