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Sample records for l2 morphological learning

  1. Chinese L1 children's English L2 verb morphology over time: individual variation in long-term outcomes.

    Science.gov (United States)

    Paradis, Johanne; Tulpar, Yasemin; Arppe, Antti

    2016-05-01

    This study examined accuracy in production and grammaticality judgements of verb morphology by eighteen Chinese-speaking children learning English as a second language (L2) followed longitudinally from four to six years of exposure to English, and who began to learn English at age 4;2. Children's growth in accuracy with verb morphology reached a plateau by six years, where 11/18 children did not display native-speaker levels of accuracy for one or more morphemes. Variation in children's accuracy with verb morphology was predicted by their English vocabulary size and verbal short-term memories primarily, and quality and quantity of English input at home secondarily. This study shows that even very young L2 learners might not all catch up to native speakers in this time frame and that non-age factors play a role in determining individual variation in child L2 learners' long-term outcomes with English morphology.

  2. Input frequencies in processing of verbal morphology in L1 and L2: Evidence from Russian

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    Tatiana Chernigovskaya

    2011-02-01

    Full Text Available In this study we take a usage-based perspective on the analysis of data from the acquisition of verbal morphology by Norwegian adult learners of L2 Russian, as compared to children acquiring Russian as an L1. According to the usage-based theories, language learning is input-driven and frequency of occurrence of grammatical structures and lexical items in the input plays a key role in this process. We have analysed to what extent the acquisition and processing of Russian verbal morphology by children and adult L2 learners is dependent on the input factors, in particular on type and token frequencies. Our analysis of the L2 input based on the written material used in the instruction shows a different distribution of frequencies as compared to the target language at large. The results of the tests that elicited present tense forms of verbs belonging to four different inflectional classes (-AJ-, -A-, -I-, and -OVA- have demonstrated that for both Russian children and L2 learners type frequency appears to be an important factor, influencing both correct stem recognition and generalisations. The results have also demonstrated token frequency effects. For L2 learners we observed also effects of formal instruction and greater reliance on morphological cues. In spite of the fact that L2 learners did not match completely any of the child groups, there are many similarities between L1 and L2 morphological processing, the main one being the role of frequency.

  3. The Design of Morphological/Linguistic Data in L1 and L2 ...

    African Journals Online (AJOL)

    user

    learners' MA of an L1 or L2 can be measured (and, as an extension to this, that users' and .... and they could activate these strategies and skills when confronted with new .... cussion of a wide range of morphological phenomena in English.

  4. Morphological Family Size effects in L1 and L2 processing: An electrophysiological study

    NARCIS (Netherlands)

    Mulder, K.; Schreuder, R.; Dijkstra, A.F.J.

    2013-01-01

    The present study examined Morphological Family Size effects in first and second language processing. Items with a high or low Dutch (L1) Family Size were contrasted in four experiments involving Dutch–English bilinguals. In two experiments, reaction times (RTs) were collected in English (L2) and

  5. Does Morphology Play an Important Role in L2 Chinese Vocabulary Acquisition?

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    Zhang, Haomin

    2016-01-01

    The present study examined the role of morphological awareness in second language (L2) Chinese vocabulary acquisition through an investigation of linguistic universality and specificity underlying morphological awareness. Morphological awareness in this study was conceptualized as a universal and sharable cognitive resource as well as a…

  6. Brain signatures of early lexical and morphological learning of a new language.

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    Havas, Viktória; Laine, Matti; Rodríguez Fornells, Antoni

    2017-07-01

    Morphology is an important part of language processing but little is known about how adult second language learners acquire morphological rules. Using a word-picture associative learning task, we have previously shown that a brief exposure to novel words with embedded morphological structure (suffix for natural gender) is enough for language learners to acquire the hidden morphological rule. Here we used this paradigm to study the brain signatures of early morphological learning in a novel language in adults. Behavioural measures indicated successful lexical (word stem) and morphological (gender suffix) learning. A day after the learning phase, event-related brain potentials registered during a recognition memory task revealed enhanced N400 and P600 components for stem and suffix violations, respectively. An additional effect observed with combined suffix and stem violations was an enhancement of an early N2 component, most probably related to conflict-detection processes. Successful morphological learning was also evident in the ERP responses to the subsequent rule-generalization task with new stems, where violation of the morphological rule was associated with an early (250-400ms) and late positivity (750-900ms). Overall, these findings tend to converge with lexical and morphosyntactic violation effects observed in L1 processing, suggesting that even after a short exposure, adult language learners can acquire both novel words and novel morphological rules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Grapho-Morphological Awareness in Spanish L2 Reading: How Do Learners Use This Metalinguistic Skill?

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    Miguel, Nausica Marcos

    2012-01-01

    This paper contributes to the literature on the transferability of grapho-morphological awareness (GMA) for second language (L2) learners by analysing L2 learners' knowledge of morphology in reading. GMA helps readers to identify grammatical categories, infer meanings of unfamiliar words, and access stored lexical information. Previous research…

  8. The Impact of Resilience on L2 Learners' Motivated Behaviour and Proficiency in L2 Learning

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    Kim, Tae-Young; Kim, Yoon-Kyoung

    2017-01-01

    This exploratory study focused on the factors that constitute second language (L2) learners' resilience, and how these factors are related to L2 learning by investigating what relation resilience may have to motivated behaviour and proficiency in English learning. A total of 1620 secondary school learners of English participated in a questionnaire…

  9. Gaming as Extramural English L2 Learning and L2 Proficiency among Young Learners

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    Sylven, Liss Kerstin; Sundqvist, Pia

    2012-01-01

    Today, playing digital games is an important part of many young people's everyday lives. Claims have been made that certain games, in particular massively multiplayer online role-playing games (MMORPGs) provide L2 English learners with a linguistically rich and cognitively challenging virtual environment that may be conducive to L2 learning, as…

  10. The interrelatedness of lexis and morphology in English language learning

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    Danilović-Jeremić Jelena P.

    2017-01-01

    Full Text Available The past few decades have seen a sparked interest in the development of vocabulary knowledge in both L1 and L2 learners, resulting in an ever increasing body of research which supports the view that vocabulary and morphology are closely related. Morphological awareness, encompassing the knowledge of derivational and inflectional forms, is nowadays thought to be a critical element of vocabulary growth, contributing to a rapid expansion in children's lexicon from the fourth grade to high school (Nagy & Herman, 1987. There are indications of a similar but much slower and more challenging process taking place in the EFL teaching/learning context. Nevertheless, the relationships between various aspects of morphological awareness and vocabulary knowledge have not been investigated in depth, and even less so in Serbian EFL learners. Therefore, the aim of this paper is to explore the aforementioned issue in upper-intermediate Serbian EFL learners, first-year students majoring in English at the Faculty of Philology and Arts in Kragujevac. Their performance on the word segmentation and suffix elicitation task, as measures of receptive and productive morphological awareness (Hayashi & Murphy, 2011, was statistically analyzed and examined in relation to their vocabulary size (Nation, 1990; 2001. The results obtained contribute to our growing understanding of L2 lexical knowledge in EFL learners and have pedagogical implications.

  11. The Effect of Perceptual Learning on L2 Vocabulary Learning and Retention

    OpenAIRE

    BEDİR, Gülay; BEKTAŞ BEDİR, Sevgi

    2018-01-01

    It is thought that learning styles have an effecton learning foreign language. This study aims to determine effects ofperceptual learning styles on L2 vocabulary learning and retention. Learningstyle preferences were assessed in the current study through the section ofCohen et al.’s Learning Style Survey (LSS) corresponding to the perceptualmodalities and achievement tests developed by the researcher was used to assessvocabulary learning and retention. And an open-ended question is tried toan...

  12. Influence of syllable structure on L2 auditory word learning.

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    Hamada, Megumi; Goya, Hideki

    2015-04-01

    This study investigated the role of syllable structure in L2 auditory word learning. Based on research on cross-linguistic variation of speech perception and lexical memory, it was hypothesized that Japanese L1 learners of English would learn English words with an open-syllable structure without consonant clusters better than words with a closed-syllable structure and consonant clusters. Two groups of college students (Japanese group, N = 22; and native speakers of English, N = 21) learned paired English pseudowords and pictures. The pseudoword types differed in terms of the syllable structure and consonant clusters (congruent vs. incongruent) and the position of consonant clusters (coda vs. onset). Recall accuracy was higher for the pseudowords in the congruent type and the pseudowords with the coda-consonant clusters. The syllable structure effect was obtained from both participant groups, disconfirming the hypothesized cross-linguistic influence on L2 auditory word learning.

  13. Event-related brain potentials and second language learning: syntactic processing in late L2 learners at different L2 proficiency levels

    NARCIS (Netherlands)

    Hell, J.G. van; Tokowicz, N.

    2010-01-01

    There are several major questions in the literature on late second language (L2) learning and processing. Some of these questions include: Can late L2 learners process an L2 in a native-like way? What is the nature of the differences in L2 processing among L2 learners at different levels of L2

  14. Learning and Teaching L2 Collocations: Insights from Research

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    Szudarski, Pawel

    2017-01-01

    The aim of this article is to present and summarize the main research findings in the area of learning and teaching second language (L2) collocations. Being a large part of naturally occurring language, collocations and other types of multiword units (e.g., idioms, phrasal verbs, lexical bundles) have been identified as important aspects of L2

  15. Learning from Expository Text in L2 Reading: Memory for Causal Relations and L2 Reading Proficiency

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    Hosoda, Masaya

    2017-01-01

    This study explored the relation between second-language (L2) readers' memory for causal relations and their learning outcomes from expository text. Japanese students of English as a foreign language (EFL) with high and low L2 reading proficiency read an expository text. They completed a causal question and a problem-solving test as measures of…

  16. Learning to perceive and recognize a second language: the L2LP model revised.

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    van Leussen, Jan-Willem; Escudero, Paola

    2015-01-01

    We present a test of a revised version of the Second Language Linguistic Perception (L2LP) model, a computational model of the acquisition of second language (L2) speech perception and recognition. The model draws on phonetic, phonological, and psycholinguistic constructs to explain a number of L2 learning scenarios. However, a recent computational implementation failed to validate a theoretical proposal for a learning scenario where the L2 has less phonemic categories than the native language (L1) along a given acoustic continuum. According to the L2LP, learners faced with this learning scenario must not only shift their old L1 phoneme boundaries but also reduce the number of categories employed in perception. Our proposed revision to L2LP successfully accounts for this updating in the number of perceptual categories as a process driven by the meaning of lexical items, rather than by the learners' awareness of the number and type of phonemes that are relevant in their new language, as the previous version of L2LP assumed. Results of our simulations show that meaning-driven learning correctly predicts the developmental path of L2 phoneme perception seen in empirical studies. Additionally, and to contribute to a long-standing debate in psycholinguistics, we test two versions of the model, with the stages of phonemic perception and lexical recognition being either sequential or interactive. Both versions succeed in learning to recognize minimal pairs in the new L2, but make diverging predictions on learners' resulting phonological representations. In sum, the proposed revision to the L2LP model contributes to our understanding of L2 acquisition, with implications for speech processing in general.

  17. Factors Affecting the Use of Self-Regulated L2 Learning Strategies in Turkish FLE Context

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    Köksal, Dinçay; Dündar, Sinem

    2017-01-01

    This study aims to investigate the overall self-regulated L2 learning strategy use of L2 learners depending upon the Strategic Self-Regulation (S[superscript 2]R) Model proposed by Oxford (2011), and to examine the relationships between their reported self-regulated L2 strategy use and their personality traits, identity, beliefs about L2 learning,…

  18. The Role of Statistical Learning and Working Memory in L2 Speakers' Pattern Learning

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    McDonough, Kim; Trofimovich, Pavel

    2016-01-01

    This study investigated whether second language (L2) speakers' morphosyntactic pattern learning was predicted by their statistical learning and working memory abilities. Across three experiments, Thai English as a Foreign Language (EFL) university students (N = 140) were exposed to either the transitive construction in Esperanto (e.g., "tauro…

  19. L2 speakers decompose morphologically complex verbs: fMRI evidence from priming of transparent derived verbs

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    Sophie eDe Grauwe

    2014-10-01

    Full Text Available In this fMRI long-lag priming study, we investigated the processing of Dutch semantically transparent, derived prefix verbs. In such words, the meaning of the word as a whole can be deduced from the meanings of its parts, e.g. wegleggen ‘put aside’. Many behavioral and some fMRI studies suggest that native (L1 speakers decompose transparent derived words. The brain region usually implicated in morphological decomposition is the left inferior frontal gyrus (LIFG. In non-native (L2 speakers, the processing of transparent derived words has hardly been investigated, especially in fMRI studies, and results are contradictory: Some studies find more reliance on holistic (i.e. non-decompositional processing by L2 speakers; some find no difference between L1 and L2 speakers. In this study, we wanted to find out whether Dutch transparent derived prefix verbs are decomposed or processed holistically by German L2 speakers of Dutch. Half of the derived verbs (e.g. omvallen ‘fall down’ were preceded by their stem (e.g. vallen ‘fall’ with a lag of 4 to 6 words (‘primed’; the other half (e.g. inslapen ‘fall asleep’ were not (‘unprimed’. L1 and L2 speakers of Dutch made lexical decisions on these visually presented verbs. Both ROI analyses and whole-brain analyses showed that there was a significant repetition suppression effect for primed compared to unprimed derived verbs in the LIFG. This was true both for the analyses over L2 speakers only and for the analyses over the two language groups together. The latter did not reveal any interaction with language group (L1 vs. L2 in the LIFG. Thus, L2 speakers show a clear priming effect in the LIFG, an area that has been associated with morphological decomposition. Our findings are consistent with the idea that L2 speakers engage in decomposition of transparent derived verbs rather than processing them holistically.

  20. RELATIONSHIP AMONG BRAIN HEMISPHERIC DOMINANCE, ATTITUDE TOWARDS L1 AND L2, GENDER, AND LEARNING SUPRASEGMENTAL FEATURES

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    Mohammad Hadi Mahmoodi

    2016-07-01

    Full Text Available Oral skills are important components of language competence. To have good and acceptable listening and speaking, one must have good pronunciation, which encompasses segmental and suprasegmental features. Despite extensive studies on the role of segmental features and related issues in listening and speaking, there is paucity of research on the role of suprasegmental features in the same domain. Conducting studies which aim at shedding light on the issues related to learning suprasegmental features can help language teachers and learners in the process of teaching/learning English as a foreign language. To this end, this study was designed to investigate the relationship among brain hemispheric dominance, gender, attitudes towards L1 and L2, and learning suprasegmental features in Iranian EFL learners. First, 200 Intermediate EFL learners were selected from different English language teaching institutes in Hamedan and Isfahan, two provinces in Iran, as the sample. Prior to the main stage of the study, Oxford Placement Test (OPT was used to homogenize the proficiency level of all the participants. Then, the participants were asked to complete the Edinburgh Handedness Questionnaire to determine their dominant hemisphere. They were also required to answer two questionnaires regarding their attitudes towards L1 and L2. Finally, the participants took suprasegmental features test. The results of the independent samples t-tests indicated left-brained language learners’ superiority in observing and learning suprasegmental features. It was also found that females are better than males in producing suprasegmental features. Furthermore, the results of Pearson Product Moment Correlations indicated that there is significant relationship between attitude towards L2 and learning suprasegmental features. However, no significant relationship was found between attitude towards L1 and learning English suprasegmental features. The findings of this study can

  1. Task-based Language Learning in Bilingual Montessori Elementary Schools: Customizing Foreign Language Learning and Promoting L2 Speaking Skills

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    Jana Winnefeld

    2012-01-01

    Full Text Available Foreign language learning has been a part of German elementary schools for several years now. Montessori schools focusing on individual learning, i.e. mostly independent from the teacher and based on auto-education, interest, and free choice, are also asked to teach an L2. The original lack of a concept of L2 learning for this environment has brought forth different approaches. Bilingual education seems to be feasible and applicable in Montessori education. The downside to this is that even in a bilingual classroom the Montessori way of learning may not allow for very much oral production of the foreign language. The role of L2 production (cf. Swain 1985, 1995, 2005 for language acquisition has been theoretically claimed and empirically investigated. Output can have a positive influence on L2 learning (cf. e.g. Izumi 2002, Keck et al. 2006. This also applies to interaction (cf. Long 1996, where negotiation of meaning and modified output are factors supporting L2 development (cf. e.g. de la Fuente 2002, McDonough 2005. Task-based Language Learning (TBLL presents itself as one way to promote oral language production and to provide opportunities for meaning-negotiation. Especially tasks with required information exchange and a closed outcome have been shown to be beneficial for the elicitation of negotiation of meaning and modified output. This paper argues that TBLL is a promising approach for the facilitation of L2 production and thus the development of speaking skills in a Montessori context. It also hypothesizes that TBLL can be implemented in a bilingual Montessori environment while still making the Montessori way of learning possible. Different tasks on various topics, examples of which are presented in this article, can lay the foundation for this. Offering such tasks in a bilingual Montessori elementary classroom promises to foster language production and the use of communication strategies like negotiation of meaning, both being

  2. Applying Cognitive Linguistics to Instructed L2 Learning: The English Modals

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    Tyler, Andrea; Mueller, Charles M.; Ho, Vu

    2010-01-01

    This paper reports the results of a quasi-experimental effects-of-instruction study examining the efficacy of applying a Cognitive Linguistic (CL) approach to L2 learning of the semantics of English modals. In spite of their frequency in typical input, modal verbs present L2 learners with difficulties, party due to their inherent…

  3. Learning L2 German vocabulary through reading: the effect of three enhancement techniques compared

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    Peters, E.; Hulstijn, J.H.; Sercu, L.; Lutjeharms, M.

    2009-01-01

    This study investigated three techniques designed to increase the chances that second language (L2) readers look up and learn unfamiliar words during and after reading an L2 text. Participants in the study, 137 college students in Belgium (L1 = Dutch, L2 = German), were randomly assigned to one of

  4. Active Learning through Materials Development: A Project for the Advanced L2 Classroom

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    Katrina Daly Thompson

    2008-01-01

    Full Text Available Building on the notion of active learning, the assumption that students learn more when given opportunities to practice using their skills and to receive feedback on their performance, this article de-scribes a project undertaken in an Advanced (third-year Swahili course in which students were given the opportunity to develop L2 materials for computer-mediated peer instruction. The article exam-ines the goals, design and results of the project in light of the litera-ture on active learning and learner autonomy, and suggests how the project might be improved in order to serve as a model for other Ad-vanced L2 courses.

  5. L2 Grammatical Gender in a Complex Morphological System: The Case of German

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    Spinner, Patti; Juffs, Alan

    2008-01-01

    In order to determine the nature of naturalistic learners' difficulty with grammatical gender in a complex morphological system, the longitudinal production data of an early naturalistic L1-Italian and L1-Turkish learner who are acquiring German are examined in light of current theories of gender within Chomsky's (1995) Minimalist Program. After…

  6. Posters, Self-Directed Learning, and L2 Vocabulary Acquisition

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    Cetin, Yakup; Flamand, Lee

    2013-01-01

    Posters, either as promotions by various ELT publishing houses or prepared by ELT teachers and students, are widely used on the walls of many foreign language classrooms. Many of them consist of colourful pictures along with L2 vocabulary, grammar, and texts in order to contribute to the foreign language learning process. However, many ELT…

  7. The acquisition of interlanguage morphology : a study into the role of morphology in the L2 learner's mental lexicon

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    Lowie, Wander Marius

    1998-01-01

    Introduction 1.1 Morphology and second language learning If Dutch learners of English encounter a word like undoable, they may recognise it because they have seen it before and have remembered it. They may also fail to recognise it and guess the meaning of the word on the basis of the context. A

  8. L1 French learning of L2 Spanish past tenses: L1 transfer versus aspect and interface issues

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    José Amenós Pons

    2017-09-01

    Full Text Available This paper examines the process of acquiring L2s that are closely related to the L1 through data on how adult French speakers learning L2 Spanish in a formal setting develop knowledge and use of past tenses in this L2. We consider the role of transfer and simplification in acquiring mental representations of the L2 grammar, specifically in the area of tense and aspect, and how learners deal with integrating grammatically encoded, lexical and discursive information, including mismatching feature combinations leading to particular inferential effects on interpretation. Data is presented on the Spanish past tenses (simple and compound past, pluperfect, imperfect and progressive forms from two tasks, an oral production filmretell and a multiple-choice interpretation task, completed by learners at A2, B1, B2 and C1 CEFR levels (N = 20-24 per level. L1 influence is progressively attenuated as proficiency increases. Difficulties were not always due to negative L1 transfer, but related also to grammar-discourse interface issues when integrating linguistic and pragmatic information in the interpretation process. This has clear implications for the teaching of closely related languages: instruction should not only focus on crosslinguistic contrasts, but also prioritize uses requiring complex interface integration, which are harder to process.

  9. L2 Vocabulary Acquisition in Children: Effects of Learning Method and Cognate Status

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    Tonzar, Claudio; Lotto, Lorella; Job, Remo

    2009-01-01

    In this study we investigated the effects of two learning methods (picture- or word-mediated learning) and of word status (cognates vs. noncognates) on the vocabulary acquisition of two foreign languages: English and German. We examined children from fourth and eighth grades in a school setting. After a learning phase during which L2 words were…

  10. Learning English with "The Sims": Exploiting Authentic Computer Simulation Games for L2 Learning

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    Ranalli, Jim

    2008-01-01

    With their realistic animation, complex scenarios and impressive interactivity, computer simulation games might be able to provide context-rich, cognitively engaging virtual environments for language learning. However, simulation games designed for L2 learners are in short supply. As an alternative, could games designed for the mass-market be…

  11. Rapid L2 Word Learning through High Constraint Sentence Context: An Event-Related Potential Study

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    Baoguo Chen

    2017-12-01

    Full Text Available Previous studies have found quantity of exposure, i.e., frequency of exposure (Horst et al., 1998; Webb, 2008; Pellicer-Sánchez and Schmitt, 2010, is important for second language (L2 contextual word learning. Besides this factor, context constraint and L2 proficiency level have also been found to affect contextual word learning (Pulido, 2003; Tekmen and Daloglu, 2006; Elgort et al., 2015; Ma et al., 2015. In the present study, we adopted the event-related potential (ERP technique and chose high constraint sentences as reading materials to further explore the effects of quantity of exposure and proficiency on L2 contextual word learning. Participants were Chinese learners of English with different English proficiency levels. For each novel word, there were four high constraint sentences with the critical word at the end of the sentence. Learners read sentences and made semantic relatedness judgment afterwards, with ERPs recorded. Results showed that in the high constraint condition where each pseudoword was embedded in four sentences with consistent meaning, N400 amplitude upon this pseudoword decreased significantly as learners read the first two sentences. High proficiency learners responded faster in the semantic relatedness judgment task. These results suggest that in high quality sentence contexts, L2 learners could rapidly acquire word meaning without multiple exposures, and L2 proficiency facilitated this learning process.

  12. The Effects of Giving and Receiving Marginal L1 Glosses on L2 Vocabulary Learning by Upper Secondary Learners

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    Samian, Hosein Vafadar; Foo, Thomas Chow Voon; Mohebbi, Hassan

    2016-01-01

    This paper reports the findings of a study that investigated the effect of giving and receiving marginal L1 glosses on L2 vocabulary learning. To that end, forty nine Iranian learners of English were assigned to three different experimental conditions including marginal L1 glosses Giver (n = 17), marginal L1 glosses Receiver (n = 17), and no…

  13. Task type and incidental L2 vocabulary learning: Repetition versus ...

    African Journals Online (AJOL)

    This study investigated the effect of task type on incidental L2 vocabulary learning. The different tasks investigated in this study differed in terms of repetition of encounters and task involvement load. In a within-subjects design, 72 Iranian learners of English practised 18 target words in three exercise conditions: three ...

  14. The Effect of Conversation Engagement on L2 Learning Opportunities

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    Chen, Wenxue

    2017-01-01

    This article reviews patterns of interaction (i.e. learner role relationships) in peer communicative tasks, and uses data collected from different tasks to explain what happens in peer interaction and its impact on the learning opportunities interlocutors create for each other. It proposes that, with L2 peer interaction gaining popularity in…

  15. Investigating the Role of Multiple Intelligences in Determining Vocabulary Learning Strategies for L2 Learners

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    Sistani, Mahsa; Hashemian, Mahmood

    2016-01-01

    This study, first, examined whether there was any relationship between Iranian L2 learners' vocabulary learning strategies (VLSs), on the one hand, and their multiple intelligences (MI) types, on the other hand. In so doing, it explored the extent to which MI would predict L2 learners' VLSs. To these ends, 40 L2 learners from Isfahan University of…

  16. Improving galaxy morphologies for SDSS with Deep Learning

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    Domínguez Sánchez, H.; Huertas-Company, M.; Bernardi, M.; Tuccillo, D.; Fischer, J. L.

    2018-05-01

    We present a morphological catalogue for ˜670 000 galaxies in the Sloan Digital Sky Survey in two flavours: T-type, related to the Hubble sequence, and Galaxy Zoo 2 (GZ2 hereafter) classification scheme. By combining accurate existing visual classification catalogues with machine learning, we provide the largest and most accurate morphological catalogue up to date. The classifications are obtained with Deep Learning algorithms using Convolutional Neural Networks (CNNs). We use two visual classification catalogues, GZ2 and Nair & Abraham (2010), for training CNNs with colour images in order to obtain T-types and a series of GZ2 type questions (disc/features, edge-on galaxies, bar signature, bulge prominence, roundness, and mergers). We also provide an additional probability enabling a separation between pure elliptical (E) from S0, where the T-type model is not so efficient. For the T-type, our results show smaller offset and scatter than previous models trained with support vector machines. For the GZ2 type questions, our models have large accuracy (>97 per cent), precision and recall values (>90 per cent), when applied to a test sample with the same characteristics as the one used for training. The catalogue is publicly released with the paper.

  17. L-histidine enhances learning in stressed zebrafish

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    L.P.V. Cofiel

    2009-01-01

    Full Text Available The aim of the present study was to determine the effect of the histaminergic precursor L-histidine and the H3 receptor antagonist thioperamide on the learning process of zebrafish submitted or not to confinement stress. On each of the 5 consecutive days of experiment (D1, D2, D3, D4, D5, animals had to associate an interruption of the aquarium air supply with food offering. Non-stressed zebrafish received an intraperitoneal injection of 100 mg/kg L-histidine, 10 mg/kg thioperamide or saline after training. Stressed animals received drug treatment and then were submitted to confinement stress for 1 h before the learning procedure. Time to approach the feeder was measured (in seconds and was considered to be indicative of learning. A decrease in time to approach the feeder was observed in the saline-treated group (D1 = 141.92 ± 13.57; D3 = 55 ± 13.54, indicating learning. A delay in learning of stressed animals treated with saline was observed (D1 = 217.5 ± 25.66. L-histidine facilitated learning in stressed (D1 = 118.68 ± 13.9; D2 = 45.88 ± 8.2 and non-stressed (D1 = 151.11 ± 19.20; D5 = 62 ± 14.68 animals. Thioperamide inhibited learning in non-stressed (D1 = 110.38 ± 9.49; D4 = 58.79 ± 16.83 and stressed animals (D1 = 167.3 ± 26.39; D5 = 172.15 ± 27.35. L-histidine prevented the increase in blood glucose after one session of confinement (L-histidine = 65.88 ± 4.50; control = 53 ± 3.50 mg/dL. These results suggest that the histaminergic system enhances learning and modulates stress responses in zebrafish.

  18. Verbal Inflectional Morphology in L1 and L2 Spanish: A Frequency Effects Study Examining Storage versus Composition.

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    Bowden, Harriet Wood; Gelfand, Matthew P; Sanz, Cristina; Ullman, Michael T

    2010-02-17

    This study examines the storage vs. composition of Spanish inflected verbal forms in L1 and L2 speakers of Spanish. L2 participants were selected to have mid-to-advanced proficiency, high classroom experience, and low immersion experience, typical of medium-to-advanced foreign language learners. Participants were shown the infinitival forms of verbs from either Class I (the default class, which takes new verbs) or Classes II and III (non-default classes), and were asked to produce either first-person singular present-tense or imperfect forms, in separate tasks. In the present tense, the L1 speakers showed inflected-form frequency effects (i.e., higher frequency forms were produced faster, which is taken as a reflection of storage) for stem-changing (irregular) verb-forms from both Class I (e.g., pensar-pienso) and Classes II and III (e.g., perder-pierdo), as well as for non-stem-changing (regular) forms in Classes II/III (e.g., vender-vendo), in which the regular transformation does not appear to constitute a default. In contrast, Class I regulars (e.g., pescar-pesco), whose non-stem-changing transformation constitutes a default (e.g., it is applied to new verbs), showed no frequency effects. L2 speakers showed frequency effects for all four conditions (Classes I and II/III, regulars and irregulars). In the imperfect tense, the L1 speakers showed frequency effects for Class II/III (-ía-suffixed) but not Class I (-aba-suffixed) forms, even though both involve non-stem-change (regular) default transformations. The L2 speakers showed frequency effects for both types of forms. The pattern of results was not explained by a wide range of potentially confounding experimental and statistical factors, and does not appear to be compatible with single-mechanism models, which argue that all linguistic forms are learned and processed in associative memory. The findings are consistent with a dual-system view in which both verb class and regularity influence the storage vs

  19. L2 learner age from a contextualised perspective

    Directory of Open Access Journals (Sweden)

    Jelena Mihaljeviđ Djigunoviđ

    2014-01-01

    Full Text Available In this qualitative study the author focuses on age effects on young learners’ L2 development by comparing the L2 learning processes of six young learners in an instructed setting: three who had started learning English as L2 at age 6/7 and three who had started at age 9/10. Both earlier and later young beginners were followed for three years (during their second, third and fourth year of learning English. The participants’ L2 development was measured through their oral output elicited by a two-part speaking task administered each year. Results of the analyses are interpreted taking into account each learners’ individual characteristics (learning ability, attitudes and motivation, self-concept and the characteristics of the context in which they were learning their L2 (attitudes of school staff and parents to early L2 learning, home support, in-class and out-of-class exposure to L2, socio-economic status. The findings show that earlier and later young beginners follow different trajectories in their L2 learning, which reflects different interactions which age enters into with the other variables.

  20. Incidental Learning of Gender Agreement in L2.

    Science.gov (United States)

    Denhovska, Nadiia; Serratrice, Ludovica

    2017-10-01

    Incidental learning of grammar has been an area of interest for many decades; nevertheless, existing research has primarily focused on artificial or semi-artificial languages. The present study examines the incidental acquisition of the grammar of a natural language by exposing adult speakers of an ungendered L1 (English) to the gender agreement patterns in Russian (a language that was novel to the learners). Both receptive and productive knowledge and the mediating role of working memory (WM) in learning were measured. Speakers of the ungendered language were able to successfully acquire receptive but not productive grammatical knowledge in a new language under incidental exposure. WM was engaged in production but not in a grammaticality judgment task in the incidental learning condition, indicating cognitive effort during knowledge retrieval.

  1. The Effects of Multimedia Annotations on Iranian EFL Learners’ L2 Vocabulary Learning

    Directory of Open Access Journals (Sweden)

    Saeideh Ahangari

    2010-05-01

    Full Text Available In our modern technological world, Computer-Assisted Language learning (CALL is a new realm towards learning a language in general, and learning L2 vocabulary in particular. It is assumed that the use of multimedia annotations promotes language learners’ vocabulary acquisition. Therefore, this study set out to investigate the effects of different multimedia annotations (still picture annotations, dynamic picture annotations, and written annotations on L2 vocabulary learning. To fulfill this objective, the researchers selected sixty four EFL learners as the participants of this study. The participants were randomly assigned to one of the four groups: a control group that received no annotations and three experimental groups that received:  still picture annotations, dynamic picture annotations, and written annotations. Each participant was required to take a pre-test. A vocabulary post- test was also designed and administered to the participants in order to assess the efficacy of each annotation. First for each group a paired t-test was conducted between their pre and post test scores in order to observe their improvement; then through an ANCOVA test the performance of four groups was compared. The results showed that using multimedia annotations resulted in a significant difference in the participants’ vocabulary learning. Based on the results of the present study, multimedia annotations are suggested as a vocabulary teaching strategy.

  2. An Introduction of Zoltán D?rnyei's L2 Motivational Theories%An Introduction of Zoltán Dörnyei's L2 Motivational Theories

    Institute of Scientific and Technical Information of China (English)

    王晓磊; 周密

    2016-01-01

    Professor Zoltán D?rnyei is an influential researcher of L2 learning motivation. Since 1990s, he put forward several important L2 learning motivational theories and made special contribution to this field. This paper introduces his four L2 learn-ing motivational theories:1)Three-level framework of L2 motivation;2) Process model of L2 motivation;3)The L2 Motivation-al Self System;4) Directed Motivational Currents (DMC).

  3. Differential expression of Meis2, Mab21l2 and Tbx3 during limb development associated with diversification of limb morphology in mammals.

    Science.gov (United States)

    Dai, Mengyao; Wang, Yao; Fang, Lu; Irwin, David M; Zhu, Tengteng; Zhang, Junpeng; Zhang, Shuyi; Wang, Zhe

    2014-01-01

    Bats are the only mammals capable of self-powered flight using wings. Differing from mouse or human limbs, four elongated digits within a broad wing membrane support the bat wing, and the foot of the bat has evolved a long calcar that spread the interfemoral membrane. Our recent mRNA sequencing (mRNA-Seq) study found unique expression patterns for genes at the 5' end of the Hoxd gene cluster and for Tbx3 that are associated with digit elongation and wing membrane growth in bats. In this study, we focused on two additional genes, Meis2 and Mab21l2, identified from the mRNA-Seq data. Using whole-mount in situ hybridization (WISH) we validated the mRNA-Seq results for differences in the expression patterns of Meis2 and Mab21l2 between bat and mouse limbs, and further characterize the timing and location of the expression of these two genes. These analyses suggest that Meis2 may function in wing membrane growth and Mab21l2 may have a role in AP and DV axial patterning. In addition, we found that Tbx3 is uniquely expressed in the unique calcar structure found in the bat hindlimb, suggesting a role for this gene in calcar growth and elongation. Moreover, analysis of the coding sequences for Meis2, Mab21l2 and Tbx3 showed that Meis2 and Mab21l2 have high sequence identity, consistent with the functions of genes being conserved, but that Tbx3 showed accelerated evolution in bats. However, evidence for positive selection in Tbx3 was not found, which would suggest that the function of this gene has not been changed. Together, our findings support the hypothesis that the modulation of the spatiotemporal expression patterns of multiple functional conserved genes control limb morphology and drive morphological change in the diversification of mammalian limbs.

  4. L1 and L2 Distance Effects in Learning L3 Dutch

    Science.gov (United States)

    Schepens, Job J.; der Slik, Frans; Hout, Roeland

    2016-01-01

    Many people speak more than two languages. How do languages acquired earlier affect the learnability of additional languages? We show that linguistic distances between speakers' first (L1) and second (L2) languages and their third (L3) language play a role. Larger distances from the L1 to the L3 and from the L2 to the L3 correlate with lower…

  5. Online Dutch L2 Learning in Adult Education: Educators' and Providers' Viewpoints on Needs, Advantages and Disadvantages

    Science.gov (United States)

    De Paepe, Liesbeth; Zhu, Chang; Depryck, Koen

    2018-01-01

    This study critically addresses the assumptions made by educators and providers in the field of Dutch second language (L2) acquisition about the online learning of Dutch L2. These include assumptions about advantages and disadvantages of online language learning, such as flexibility, learner autonomy, enhanced opportunities for remediation and…

  6. Incidental Learning of Gender Agreement in L2

    Science.gov (United States)

    Denhovska, Nadiia; Serratrice, Ludovica

    2017-01-01

    Incidental learning of grammar has been an area of interest for many decades; nevertheless, existing research has primarily focused on artificial or semi-artificial languages. The present study examines the incidental acquisition of the grammar of a natural language by exposing adult speakers of an ungendered L1 (English) to the gender agreement…

  7. GLI ERRORI DI ITALIANO L1 ED L2: INTERFERENZA E APPRENDIMENTO

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    Rosaria Solarino

    2011-02-01

    Full Text Available Si può oggi affrontare il tema degli errori di italiano da una prospettiva che possa giovare contemporaneamente a docenti di italiano L1 ed L2? Noi pensiamo di sì: la ricerca glottodidattica sembra aver ormai apprestato un terreno comune alle due situazioni di apprendimento, sgombrando il campo da vecchi pregiudizi e distinzioni che appaiono ormai superate. Attraverso la contrapposizione di concetti quali “lingua parlata/lingua scritta”,  “errori di lingua / errori di linguaggio”, “apprendimento spontaneo/apprendimento guidato”, “italiano L1/italiano L2”, “errori di apprendimento/errori di interferenza, si indicano diversi criteri per la interpretazione degli errori e la loro valutazione in relazione alle cause, alle situazioni comunicative, ai contesti o allo stadio di evoluzione dell’apprendimento della lingua.     Errors in italian L1 and L2: interference and learning   Can errors in Italian be approached in a way that benefits both L1 and L2 Italian teachers? We believe so: glottodidactic research seems to have prepared a common terrain for these two learning situations, clearing the field of old prejudices and obsolete distinctions.  Through the juxtaposition of concepts like “spoken language/written language”, “language errors/speech errors”, “spontaneous learning/guided learning”, “L1 Italian/L2 Italian”, “learning errors/interference errors”, different criteria for interpreting errors and evaluating them in relation to their causes, to communicative situations, to contexts and the developmental state in learning a language are singled out.

  8. Morphological and molecular characterization of L-methioninase ...

    African Journals Online (AJOL)

    Six species of L-methioninase producing Aspergillus species, isolated from Egyptian soil, were selected for comprehensive morphotypic and molecular characterization. Based on morphological and physiological features, these isolates were identified as Aspergillus flavipes, Aspergillus carneus, Aspergillus flavus, ...

  9. Positive and negative emotions underlie motivation for L2 learning

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    Peter D. MacIntyre

    2017-03-01

    Full Text Available The role of basic emotions in SLA has been underestimated in both research and pedagogy. The present article examines 10 positive emotions (joy, gratitude, serenity, interest, hope, pride, amusement, inspiration, awe, and love and 9 negative emotions (anger, contempt, disgust, embarrassment, guilt, hate, sadness, feeling scared, and being stressed. The emotions are correlated with core variables chosen from three well-known models of L2 motivation: Gardner’s integrative motive, Clément’s social-contextual model, and Dörnyei’s L2 self system. Respondents came from Italian secondary schools, and most participants were from monolingual Italian speaking homes. They described their motivation and emotion with respect to learning German in a region of Italy (South Tyrol that features high levels of contact between Italians and Germans. Results show that positive emotions are consistently and strongly correlated with motivation-related variables. Correlations involving negative emotions are weaker and less consistently implicated in motivation. The positivity ratio, that is, the relative prevalence of positive over negative emotion, showed strong correlations with all of the motivation constructs. Regression analysis supports the conclusion that a variety of emotions, not just one or two key ones, are implicated in L2 motivation processes in this high-contact context.

  10. Hydrogen Learning for Local Leaders – H2L3

    Energy Technology Data Exchange (ETDEWEB)

    Serfass, Patrick [Technology Transition Corporation, Washington, DC (United States)

    2017-03-30

    The Hydrogen Learning for Local Leaders program, H2L3, elevates the knowledge about hydrogen by local government officials across the United States. The program reaches local leaders directly through “Hydrogen 101” workshops and webinar sessions; the creation and dissemination of a unique report on the hydrogen and fuel cell market in the US, covering 57 different sectors; and support of the Hydrogen Student Design Contest, a competition for interdisciplinary teams of university students to design hydrogen and fuel cell systems based on technology that’s currently commercially available.

  11. Concurrent Data Elicitation Procedures, Processes, and the Early Stages of L2 Learning: A Critical Overview

    Science.gov (United States)

    Leow, Ronald P.; Grey, Sarah; Marijuan, Silvia; Moorman, Colleen

    2014-01-01

    Given the current methodological interest in eliciting direct data on the cognitive processes L2 learners employ as they interact with L2 data during the early stages of the learning process, this article takes a critical and comparative look at three concurrent data elicitation procedures currently employed in the SLA literature: Think aloud (TA)…

  12. The Concept of L2 User and the goals of Second Language Learning

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    Willy Juanggo

    2017-07-01

    Full Text Available It is generally considered that knowing one language is not enough in this era. People need to learn a second language in addition to their mother tongue to meet the demand of today’s life as many of them are becoming a part of multilingual society as well as to face the globalisation. This paper aims to demonstrate the reasons of people learning a second by looking at the several goals they want to achieve in current situation and link it to the second language learning in education context. Subsequently, it also provides some criticism against the majority of English language teachings that set native speaker’s competence as the ultimate goal and highlights the concept of L2 user as a new paradigm and its implication to second language learning.

  13. Login | Desire2Learn@UWM

    Science.gov (United States)

    Libraries A-Z Directory UW-Milwaukee Logo Desire2Learn@UWM Logo Desire2Learn@UWM, UW-Milwaukee Login For Students For Instructors Get Help With D2L Login UWM ePantherID This is the login option for UWM students ? Contact support for help with your ePantherID Non-ePantherID This is the login option used for D2L

  14. Using "Reading to Learn" (R2L) Pedagogy to Teach Discussion Genre to Non-Chinese-Speaking Students in Hong Kong

    Science.gov (United States)

    Shum, Mark Shiu-kee; Tai, Chung Pui; Shi, Dan

    2018-01-01

    Non-Chinese-speaking (NCS) South Asian students, as ethnic minority group in Hong Kong, are the main disadvantaged social cohort in Chinese language learning. It has been a challenge for L1 Chinese teachers to conduct L2 Chinese teaching to NCS students with diversified native languages and socio-cultural backgrounds. "Reading to Learn,…

  15. The idea of culture and its topicality for teaching-learning LE/L2

    Directory of Open Access Journals (Sweden)

    Edleise Mendes

    2015-09-01

    Full Text Available In recent decades, many studies and research developed in the field of teaching / learning languages, especially of foreign and second languages, have been dedicated to discuss the importance of culture and intercultural relations as members of the learning process dimensions. This concern has as principle the fact that teaching and learning a language is a much broader and complex than the simple transmission and apprehension of formal structures and rules of use of these structures process. In this article, I propose to revisit the idea of culture to then establish their relationship with language, emphasizing the relevance of this type of reflection for the teaching-learning area LE / L2, especially focusing in Portuguese . Among other things, I want to show that contemporary trends in teaching and language teacher training recognize that approaches to teaching and learning, whatever their theoretical orientations should not isolate the language of life in which we live and culture or cultures as a means to ensure language education quality and consistent with the requirements of the contemporary world.

  16. Variability in the Second Language Acquisition of Verb Morphology ...

    African Journals Online (AJOL)

    This article seeks to make a developmental study of variability in the acquisition of verb morphology by second language (L2) pupils who learn at an English input impoverished school where variability in learner language is often presumed to be quite extensive. By studying variability in such settings, it is hoped that we can ...

  17. Could a multimodal dictionary serve as a learning tool? An examination of the impact of technologically enhanced visual glosses on L2 text comprehension

    Directory of Open Access Journals (Sweden)

    Takeshi Sato

    2016-09-01

    Full Text Available This study examines the efficacy of a multimodal online bilingual dictionary based on cognitive linguistics in order to explore the advantages and limitations of explicit multimodal L2 vocabulary learning. Previous studies have examined the efficacy of the verbal and visual representation of words while reading L2 texts, concluding that it facilitates incidental word retention. This study explores other potentials of multimodal L2 vocabulary learning: explicit learning with a multimodal dictionary could enhance not only word retention, but also text comprehension; the dictionary could serve not only as a reference tool, but also as a learning tool; and technology-enhanced visual glosses could facilitate deeper text comprehension. To verify these claims, this study investigates the multimodal representations’ effects on Japanese students learning L2 locative prepositions by developing two online dictionaries, one with static pictures and one with animations. The findings show the advantage of such dictionaries in explicit learning; however, no significant differences are found between the two types of visual glosses, either in the vocabulary or in the listening tests. This study confirms the effectiveness of multimodal L2 materials, but also emphasizes the need for further research into making the technologically enhanced materials more effective.

  18. Learning English as an L2 in the Global Context: Changing English, Changing Motivation

    Science.gov (United States)

    Sung, Chit Cheung Matthew

    2013-01-01

    As the English language has become a global lingua franca today, it is not surprising that changes in attitudes and perceptions towards learning English in the international context have taken place at the same time. In this paper, I critically examine the notion of "integrative motivation" in the literature of second language (L2)…

  19. The Impact of Blended e-Learning on Undergraduate Academic Essay Writing in English (L2)

    Science.gov (United States)

    Ferriman, Nicholas

    2013-01-01

    This paper describes a quasi-experimental study into the impact of a blended e-learning environment on academic writing assignments in English (L2) at a Thai international college. An experimental group of 15 students used an on-line bulletin board, as well as face-to-face (F2F) communication in class, to share information for essay topics they…

  20. L1 and L2 Strategy Use in Reading Comprehension of Chinese EFL Readers

    Science.gov (United States)

    Tsai, Yea-Ru; Ernst, Cheryl; Talley, Paul C.

    2010-01-01

    This study revealed the relationship between L1 (Mandarin Chinese) and L2 (English) strategy use in L2 reading comprehension by focusing on the correlation of L1 reading ability, L2 proficiency and employed reading strategies. The participants, 222 undergraduates learning English as a foreign language (EFL), were classified into skilled and…

  1. A Case Study on the Effects of an L2 Writing Instructional Model for Blended Learning in Higher Education

    Science.gov (United States)

    So, Lee; Lee, Chung Hyun

    2013-01-01

    This case study explores EFL (English as a foreign language) students' perceptions toward a prototype of an instructional model for second language (L2) writing in blended learning and the effects of the model on the development of L2 writing skills in higher education. This model is primarily founded on the process-oriented writing approach…

  2. The Relationship between Morphological Awareness and Morphological Decomposition among English Language Learners

    Science.gov (United States)

    Kraut, Rachel

    2015-01-01

    Morphological awareness facilitates many reading processes. For this reason, L1 and L2 learners of English are often directly taught to use their knowledge of English morphology as a useful reading strategy for determining parts of speech and meaning of novel words. Over time, use of morphological awareness skills while reading develops into an…

  3. The place of morphology in learning to read in English.

    Science.gov (United States)

    Rastle, Kathleen

    2018-02-24

    Morphology is a major organising principle of English and other alphabetic languages, but has been largely neglected in theories of reading acquisition. In this article, I develop the view that learning to appreciate morphological relationships may be a vital part of acquiring a direct mapping between printed words and their meanings, represented in the ventral brain pathway of the reading network. I show that morphology provides an important degree of regularity across this mapping in English, and suggest that this regularity is directly associated with irregularity in the mapping between spelling and sound. I further show that while children in primary school display explicit knowledge of morphological relationships, there is scant evidence they show the rapid morphological analysis of printed words that skilled readers exhibit. These findings suggest that the acquisition of long-term morphological knowledge may be associated with the ongoing development of reading expertise. Implications for reading instruction are discussed. Copyright © 2018 The Author. Published by Elsevier Ltd.. All rights reserved.

  4. Neural changes underlying early stages of L2 vocabulary acquisition.

    Science.gov (United States)

    Pu, He; Holcomb, Phillip J; Midgley, Katherine J

    2016-11-01

    Research has shown neural changes following second language (L2) acquisition after weeks or months of instruction. But are such changes detectable even earlier than previously shown? The present study examines the electrophysiological changes underlying the earliest stages of second language vocabulary acquisition by recording event-related potentials (ERPs) within the first week of learning. Adult native English speakers with no previous Spanish experience completed less than four hours of Spanish vocabulary training, with pre- and post-training ERPs recorded to a backward translation task. Results indicate that beginning L2 learners show rapid neural changes following learning, manifested in changes to the N400 - an ERP component sensitive to lexicosemantic processing and degree of L2 proficiency. Specifically, learners in early stages of L2 acquisition show growth in N400 amplitude to L2 words following learning as well as a backward translation N400 priming effect that was absent pre-training. These results were shown within days of minimal L2 training, suggesting that the neural changes captured during adult second language acquisition are more rapid than previously shown. Such findings are consistent with models of early stages of bilingualism in adult learners of L2 ( e.g. Kroll and Stewart's RHM) and reinforce the use of ERP measures to assess L2 learning.

  5. Morphological analysis and DNA methylation in Conyza bonariensis L. cronquist (Asteraceae phenotypes

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    Juliana Maria de Paula

    2017-08-01

    Full Text Available ABSTRACT The species Conyza bonariensis (L. cause losses in agriculture due to their invasive capacity and resistance to herbicides like glyphosate. The species of this genus exhibit phenotypic plasticity, which complicates their identification and characterization. Thus, experiments were performed with 2 extreme C. bonariensis phenotypes (called broad leaf and narrow leaf in greenhouse conditions and in the laboratory, in order to verify if the morphological differences among these phenotypes are a genetic character or result from environmental effects. In addition to the comparative morphological analysis, assessment of DNA methylation profile was performed to detect the occurrence, or not, of differences in the epigenetic level. The morphological characteristics evaluated were length, width, shape, margin and leaves indument; plant height and stem indument; the number of capitula, flowers and seeds. The Methylation Sensitive Amplified Polymorphism technique was used to investigate the methylation levels. The morphological differences of phenotypes supposed to be C. bonariensis are probably genetic in origin and not the result of environmental effects, since, after 6 crop cycles in a greenhouse under the same environmental conditions, these phenotypes remained with the same morphological characteristics and seed production in relation to the original phenotypes found in the collection site. The different phenotypes did not show differences corresponding to DNA methylation patterns that could indicate an epigenetic effect as the cause of the differences between the 2 phenotypes. The results of morphological analysis and methylation probably indicate that maybe they are individuals of populations from different taxa not registered yet in the literature.

  6. Transforming growth factor-β2 induces morphological alteration of human corneal endothelial cells in vitro

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    Jing Wang

    2014-10-01

    Full Text Available AIM:To investigate the morphological altering effect of transforming growth factor-β2 (TGF-β2 on untransfected human corneal endothelial cells (HCECs in vitro.METHODS: After untransfected HCECs were treated with TGF-β2 at different concentrations, the morphology, cytoskeleton distribution, and type IV collagen expression of the cells were examined with inverted contrast light microscopy, fluorescence microscopy, immunofluorescence or Western Blot.RESULTS:TGF-β2 at the concentration of 3-15 μg/L had obviously alterative effects on HCECs morphology in dose and time-dependent manner, and 9 μg/L was the peak concentration. TGF-β2 (9 μg/L altered HCE cell morphology after treatment for 36h, increased the mean optical density (P<0.01 and the length of F-actin, reduced the mean optical density (P<0.01 of the collagen type IV in extracellular matrix (ECM and induced the rearrangement of F-actin, microtubule in cytoplasm and collagen type IV in ECM after treatment for 72h. CONCLUTION:TGF-β2 has obviously alterative effect on the morphology of HCECs from polygonal phenotype to enlarged spindle-shaped phenotype, in dose and time-dependence manner by inducing more, elongation and alignment of F-actin, rearrangement of microtubule and larger spread area of collagen type IV.

  7. Finding the key to successful L2 learning in groups and individuals

    Directory of Open Access Journals (Sweden)

    Wander Lowie

    2017-03-01

    Full Text Available A large body studies into individual differences in second language learning has shown that success in second language learning is strongly affected by a set of relevant learner characteristics ranging from the age of onset to motivation, aptitude, and personality. Most studies have concentrated on a limited number of learner characteristics and have argued for the relative importance of some of these factors. Clearly, some learners are more successful than others, and it is tempting to try to find the factor or combination of factors that can crack the code to success. However, isolating one or several global individual characteristics can only give a partial explanation of success in second language learning. The limitation of this approach is that it only reflects on rather general personality characteristics of learners at one point in time, while both language development and the factors affecting it are instances of complex dynamic processes that develop over time. Factors that have been labelled as “individual differences” as well as the development of proficiency are characterized by nonlinear relationships in the time domain, due to which the rate of success cannot be simply deduced from a combination of factors. Moreover, in complex dynamic systems theory (CDST literature it has been argued that a generalization about the interaction of variables across individuals is not warranted when we acknowledge that language development is essentially an individual process (Molenaar, 2015. In this paper, the viability of these generalizations is investigated by exploring the L2 development over time for two identical twins in Taiwan who can be expected to be highly similar in all respects, from their environment to their level of English proficiency, to their exposure to English, and to their individual differences. In spite of the striking similarities between these learners, the development of their L2 English over time was very different

  8. Effect of Ferrite Morphology on Sensitization of 316L Austenitic Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hun; Lee, Jun Ho; Jang, Changheui [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2013-05-15

    The sensitization behaviors of L-grade SSs having predominant austenitic structure with small amount of ferrite have not been well understood. In this regard, the effect of ferrite morphology on sensitization was investigated in this study. The sensitization behaviors of three heats of 316L and 316LN SSs were investigated, Stringer type of ferrite (316L - heat A and B) showed the early sensitization by chromium depletion at ferrite. austenite interface. And, later sensitization is due to GB sensitization. On the other hand, blocky type of ferrite (316L - heat C) showed lower DOS and higher resistance to GB sensitization. It could be due to sufficient supply of chromium from relatively large ferrite phase. As a consequence, the sensitization of 316L SSs could be affected by their ferrite morphology rather than ferrite content. The sensitized region was distinguishable from results of DL-EPR tests. It can be used as an effective method for evaluation of type of sensitization.

  9. Coastal Foredune Evolution, Part 2: Modeling Approaches for Meso-Scale Morphologic Evolution

    Science.gov (United States)

    2017-03-01

    for Meso-Scale Morphologic Evolution by Margaret L. Palmsten1, Katherine L. Brodie2, and Nicholas J. Spore2 PURPOSE: This Coastal and Hydraulics ...managers because foredunes provide ecosystem services and can reduce storm damages to coastal infrastructure, both of which increase the resiliency...MS 2 U.S. Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, Duck, NC ERDC/CHL CHETN-II-57 March 2017 2 models of

  10. E-learning og lærerkompetencer

    Directory of Open Access Journals (Sweden)

    Birgitte Heiberg

    2004-06-01

    Full Text Available Første gang publiceret i UNEV nr. 4: Undervisere og e-læring - problemer og perspektiver, september - december 2004, red. Poul Gøtke og Annette Lorentsen. ISSN 1603-5518. På flere uddannelsesinstitutioner udformes der i disse år strategier og politikker for e-learning og underviserne må således forholde sig til de muligheder som informations- og kommunikationsteknologien stiller til rådighed for deres undervisning. E-learning indebærer både teknologisk og pædagogisk omstilling: Underviserne må overveje og tilegne sig nye undervisningsformer, der måske baserer sig på nye læringsparadigmer end de kendte. De skal også tilegne sig nye teknologiske værktøjer og metoder. Ikke alle undervisere oplever det som en spændende udfordring. Der er derfor behov for at genoverveje hvordan kompetenceudviklingen for universitetsunderviserne skal organiseres i forhold til e-learning og læring generelt. I denne artikel vil jeg forsøge at belyse de barrierer kompetenceudvikling må overkomme på baggrund af de erfaringer vi har gjort os på CBS Learning Lab med kompetenceudviklingsinitiativer rettet mod e-learning, samt en nylig undersøgelse af CBS studerendes, underviseres og de studieadministrativt ansattes forhold til e-learning.

  11. Neural Correlates of Morphology Acquisition through a Statistical Learning Paradigm.

    Science.gov (United States)

    Sandoval, Michelle; Patterson, Dianne; Dai, Huanping; Vance, Christopher J; Plante, Elena

    2017-01-01

    The neural basis of statistical learning as it occurs over time was explored with stimuli drawn from a natural language (Russian nouns). The input reflected the "rules" for marking categories of gendered nouns, without making participants explicitly aware of the nature of what they were to learn. Participants were scanned while listening to a series of gender-marked nouns during four sequential scans, and were tested for their learning immediately after each scan. Although participants were not told the nature of the learning task, they exhibited learning after their initial exposure to the stimuli. Independent component analysis of the brain data revealed five task-related sub-networks. Unlike prior statistical learning studies of word segmentation, this morphological learning task robustly activated the inferior frontal gyrus during the learning period. This region was represented in multiple independent components, suggesting it functions as a network hub for this type of learning. Moreover, the results suggest that subnetworks activated by statistical learning are driven by the nature of the input, rather than reflecting a general statistical learning system.

  12. Investigating the Efficacy of an Intensive English Program and the L2 Learners’ Learning Styles

    Directory of Open Access Journals (Sweden)

    Rebecca Lee Su Ping

    2014-12-01

    Full Text Available Past research has found that many pre-university L2 learners, having completed an Intensive English Program (IEP still have difficulty in undertaking various disciplines in English-speaking tertiary institutions and continue to exhibit numerous linguistic problems (Bialystok, 2001, Celce Murcia 2001. The purpose of this paper is to present the findings on the investigation of L2 learners’ English proficiency in reading, writing, grammar, listening and speaking upon their completion of an Intensive English (IE program using their IELTS (Academic, in-house exams and English Placement Tests (EPT scores, and the efficacy of IE program.  IELTS test is chosen for this study due to its increasing popularity in Malaysia and its internationally recognised value and quality.  The study was conducted in two parts. In Part One, all 72 Level 4 IE students were given an in-house EPT (English Placement Test pre-test on their entry and another EPT post-test on their exit, and then their pre-test and post-test results were compared.  In Part Two, 22 volunteers sat the IELTS test at the end of the program. The IELTS results of the 22 volunteers were compared with those who did not.  Data were analyzed using both quantitative and qualitative methods. This paper hopes to shed some light on (i whether or not L2 learners’ English language proficiency can be significantly enhanced and influenced by an intensive English program and (ii how leaners’ perception of their own learning strategies influence their learning progress.

  13. I mål med flipped learning

    DEFF Research Database (Denmark)

    Hachmann, Roland

    2016-01-01

    Kapitlet belyser, hvordan synlige læringsmål og stilladsering er to vigtige elementer i Flipped Learning. Kapitlet belyser en række metoder til at bringe eleven i centrum for sin egen læring og hvorledes underviseren kan differentiere sin undervisning for netop at støtte denne proces......Kapitlet belyser, hvordan synlige læringsmål og stilladsering er to vigtige elementer i Flipped Learning. Kapitlet belyser en række metoder til at bringe eleven i centrum for sin egen læring og hvorledes underviseren kan differentiere sin undervisning for netop at støtte denne proces...

  14. Deep learning for studies of galaxy morphology

    Science.gov (United States)

    Tuccillo, D.; Huertas-Company, M.; Decencière, E.; Velasco-Forero, S.

    2017-06-01

    Establishing accurate morphological measurements of galaxies in a reasonable amount of time for future big-data surveys such as EUCLID, the Large Synoptic Survey Telescope or the Wide Field Infrared Survey Telescope is a challenge. Because of its high level of abstraction with little human intervention, deep learning appears to be a promising approach. Deep learning is a rapidly growing discipline that models high-level patterns in data as complex multilayered networks. In this work we test the ability of deep convolutional networks to provide parametric properties of Hubble Space Telescope like galaxies (half-light radii, Sérsic indices, total flux etc..). We simulate a set of galaxies including point spread function and realistic noise from the CANDELS survey and try to recover the main galaxy parameters using deep-learning. We compare the results with the ones obtained with the commonly used profile fitting based software GALFIT. This way showing that with our method we obtain results at least equally good as the ones obtained with GALFIT but, once trained, with a factor 5 hundred time faster.

  15. A PHOTOMETRICALLY AND MORPHOLOGICALLY VARIABLE INFRARED NEBULA IN L483

    International Nuclear Information System (INIS)

    Connelley, Michael S.; Hodapp, Klaus W.; Fuller, Gary A.

    2009-01-01

    We present narrow and broad K-band observations of the Class 0/I source IRAS 18148-0440 that span 17 years. The infrared nebula associated with this protostar in the L483 dark cloud is both morphologically and photometrically variable on a timescale of only a few months. This nebula appears to be an infrared analog to other well known optically visible variable nebulae associated with young stars, such as Hubble's Variable Nebula. Along with Cepheus A, this is one of the first large variable nebulae to be found that is only visible in the infrared. The variability of this nebula is most likely due to changing illumination of the cloud rather than any motion of the structure in the nebula. Both morphological and photometric changes are observed on a timescale only a few times longer than the light crossing time of the nebula, suggesting very rapid intrinsic changes in the illumination of the nebula. Our narrowband observations also found that H 2 knots are found nearly twice as far to the east of the source as to its west, and that H 2 emission extends farther east of the source than the previously known CO outflow.

  16. Designing an Intelligent Mobile Learning Tool for Grammar Learning (i-MoL

    Directory of Open Access Journals (Sweden)

    Munir Shuib

    2015-01-01

    Full Text Available English is the most important second language in most non-English speaking countries, including Malaysia. A good English proficiency comes from good grasp of grammar. To conquer the problems of low English proficiency among Malaysians, it is important to identify the key motivators that could facilitate the process of grammar learning. In this digital age, technology can play a very important role and mobile technology could be one of it. Thus, this study aims at designing a mobile learning tool, namely the Intelligent Mobile Learning Tool for Grammar Learning (i-MoL to act as the “on-the-go” grammar learning support via mobile phones. i-MoL helps reinforce grammar learning through mobile phone with game-like applications, inquiry-based activities and flashcard-like information. The intelligent part of i-MoL lies in its ability to map the mobile-based grammar learning content to individual’s preferred learning styles based on Felder-Silverman Learning Style Model (FSLSM. The instructional system design through the ADDIE model was used in this study as a systematic approach in designing a novel and comprehensive mobile learning tool for grammar learning. In terms of implications, this study provides insights on how mobile technologies can be utilized to meet the mobility demand among language learners today.

  17. English Orthographic Learning in Chinese-L1 Young EFL Beginners.

    Science.gov (United States)

    Cheng, Yu-Lin

    2017-12-01

    English orthographic learning, among Chinese-L1 children who were beginning to learn English as a foreign language, was documented when: (1) only visual memory was at their disposal, (2) visual memory and either some letter-sound knowledge or some semantic information was available, and (3) visual memory, some letter-sound knowledge and some semantic information were all available. When only visual memory was available, orthographic learning (measured via an orthographic choice test) was meagre. Orthographic learning was significant when either semantic information or letter-sound knowledge supplemented visual memory, with letter-sound knowledge generating greater significance. Although the results suggest that letter-sound knowledge plays a more important role than semantic information, letter-sound knowledge alone does not suffice to achieve perfect orthographic learning, as orthographic learning was greatest when letter-sound knowledge and semantic information were both available. The present findings are congruent with a view that the orthography of a foreign language drives its orthographic learning more than L1 orthographic learning experience, thus extending Share's (Cognition 55:151-218, 1995) self-teaching hypothesis to include non-alphabetic L1 children's orthographic learning of an alphabetic foreign language. The little letter-sound knowledge development observed in the experiment-I control group indicates that very little letter-sound knowledge develops in the absence of dedicated letter-sound training. Given the important role of letter-sound knowledge in English orthographic learning, dedicated letter-sound instruction is highly recommended.

  18. Thermodynamic and morphological analysis of eutectic formation of CBZ-L-Asp and L-PheOMe.HCl mixtures

    International Nuclear Information System (INIS)

    Kim, Hyun Jung; Kim, Jong Hoon; Youn, Sung Hun; Shin, Chul Soo

    2006-01-01

    The eutectic melting of a CBZ-L-Asp/L-PheOMe.HCl model mixture was investigated in kinetic, thermal, thermodynamic, rheological, and morphological aspects. From TX-phase diagrams, the eutectic composition was determined to be 0.55 M fraction of CBZ-L-Asp. The highest melting rate and the lowest apparent viscosity in the range of 55-75 deg. C were obtained at the eutectic composition. Using Arrhenius plots of melting rates and apparent viscosities, minimum activation energies in the range of 60-80 deg. C were obtained at the eutectic composition, whereas maximum values were attained below 60 deg. C. At the eutectic composition, the maximum heat of fusion, the lowest excess free energy, and the highest excess entropy values were observed by differential scanning calorimetry (DSC). A highly homogeneous morphology due to rearrangement of molecules was observed in the eutectic mixture via scanning electron microscopy and X-ray diffraction analysis. IR spectra revealed that hydrogen bonding in the mixture increases during eutectic melting

  19. POLLEN MORPHOLOGY OF CROCUS L.(IRIDACEAE IN BULGARIA

    Directory of Open Access Journals (Sweden)

    UZUNDZHALIEVA KATYA SPASOVA

    2012-06-01

    Full Text Available The pollen of the wild species from the genus Crocus L., spread in Bulgaria has been analyzed. The investigations, made by light microscope show that the pollen of these species is spherical in shape and round in outlines, comparatively big. These morphological characteristics of the pollen of the wild Bulgarian Crocuses define it as a primitive one [6]. The Scanning Electron Microscope investigations, made by Beug [1], established two types of pollen morphology. The results of our investigation led to the conclusion that the same types are also presented in Bulgarian species: – C.biflorus –type, or syncolpate and C.vernus – type, or inaperturate. Eight of the species belong to the first type and only C. pallasii belongs to the second. The pollen of C. reticulatus is with quite unclear aperture – maybe transition to the inaperturate type.

  20. Large-scale Exploration of Neuronal Morphologies Using Deep Learning and Augmented Reality.

    Science.gov (United States)

    Li, Zhongyu; Butler, Erik; Li, Kang; Lu, Aidong; Ji, Shuiwang; Zhang, Shaoting

    2018-02-12

    Recently released large-scale neuron morphological data has greatly facilitated the research in neuroinformatics. However, the sheer volume and complexity of these data pose significant challenges for efficient and accurate neuron exploration. In this paper, we propose an effective retrieval framework to address these problems, based on frontier techniques of deep learning and binary coding. For the first time, we develop a deep learning based feature representation method for the neuron morphological data, where the 3D neurons are first projected into binary images and then learned features using an unsupervised deep neural network, i.e., stacked convolutional autoencoders (SCAEs). The deep features are subsequently fused with the hand-crafted features for more accurate representation. Considering the exhaustive search is usually very time-consuming in large-scale databases, we employ a novel binary coding method to compress feature vectors into short binary codes. Our framework is validated on a public data set including 58,000 neurons, showing promising retrieval precision and efficiency compared with state-of-the-art methods. In addition, we develop a novel neuron visualization program based on the techniques of augmented reality (AR), which can help users take a deep exploration of neuron morphologies in an interactive and immersive manner.

  1. Learning to Learn Together with CSCL Tools

    Science.gov (United States)

    Schwarz, Baruch B.; de Groot, Reuma; Mavrikis, Manolis; Dragon, Toby

    2015-01-01

    In this paper, we identify "Learning to Learn Together" (L2L2) as a new and important educational goal. Our view of L2L2 is a substantial extension of "Learning to Learn" (L2L): L2L2 consists of learning to collaborate to successfully face L2L challenges. It is inseparable from L2L, as it emerges when individuals face problems…

  2. Lexical and semantic representations in the acquisition of L2 cognate and non-cognate words: evidence from two learning methods in children.

    Science.gov (United States)

    Comesaña, Montserrat; Soares, Ana Paula; Sánchez-Casas, Rosa; Lima, Cátia

    2012-08-01

    How bilinguals represent words in two languages and which mechanisms are responsible for second language acquisition are important questions in the bilingual and vocabulary acquisition literature. This study aims to analyse the effect of two learning methods (picture- vs. word-based method) and two types of words (cognates and non-cognates) in early stages of children's L2 acquisition. Forty-eight native speakers of European Portuguese, all sixth graders (mean age = 10.87 years; SD= 0.85), participated in the study. None of them had prior knowledge of Basque (the L2 in this study). After a learning phase in which L2 words were learned either by a picture- or a word-based method, children were tested in a backward-word translation recognition task at two times (immediately vs. one week later). Results showed that the participants made more errors when rejecting semantically related than semantically unrelated words as correct translations (semantic interference effect). The magnitude of this effect was higher in the delayed test condition regardless of the learning method. Moreover, the overall performance of participants from the word-based method was better than the performance of participants from the picture-word method. Results were discussed concerning the most significant bilingual lexical processing models. ©2011 The British Psychological Society.

  3. [Characteristics of Cannabis sativa L.: seed morphology, germination and growth characteristics, and distinction from Hibiscus cannabinus L].

    Science.gov (United States)

    Yoshimatsu, Kayo; Kitazawa, Takashi; Kawano, Noriaki; Iida, Osamu; Kawahara, Nobuo

    2010-02-01

    Illegal cannabis (Cannabis sativa L.) cultivation is still a social problem worldwide. Fifty inquiries on cannabis that Research Center for Medicinal Plant Resources (Tsukuba Division) received between January 1, 2000 and March 31, 2009 were itemized in to 8 categories; 1: seed identification, 2: plant identification, 3: indoor cultivation, 4: outdoor cultivation, 5: germination and growth characteristics, 6: expected amount of cannabis products derived from illegal cannabis plant, 7: non-narcotic cannabis and 8: usage of medicinal cannabis. Top three inquiries were 1: seed identification (16 cases), 3: indoor cultivation (10 cases) and 4: outdoor cultivation (6 cases). Characteristics of cannabis, namely seed morphology, germination and growth characteristics, and distinction from kenaf (Hibiscus cannabinus L.) that is frequently misjudged as cannabis, were studied to contribute for prevention of illegal cannabis cultivation.

  4. Effects of Gloss Type on Text Recall and Incidental Vocabulary Learning in Mobile-Assisted L2 Listening

    Science.gov (United States)

    Çakmak, Fidel; Erçetin, Gülcan

    2018-01-01

    This study investigates the effects of multimedia glosses on text recall and incidental vocabulary learning in a mobile-assisted L2 listening task. A total of 88 participants with a low level of proficiency in English were randomly assigned to one of four conditions that involved single channel (textual-only, pictorial-only) and dual-channel…

  5. Evaluating Bilingual and Monolingual Dictionaries for L2 Learners.

    Science.gov (United States)

    Hunt, Alan

    1997-01-01

    A discussion of dictionaries and their use for second language (L2) learning suggests that lack of computerized modern language corpora can adversely affect bilingual dictionaries, commonly used by L2 learners, and shows how use of such corpora has benefitted two contemporary monolingual L2 learner dictionaries (1995 editions of the Longman…

  6. Morphological diversity of wild medicinal Paris L. from China and ...

    African Journals Online (AJOL)

    Paris L. (Trilliaceae) is a temperate genus of about 24 perennial herbaceous species distributed from Europe to Eastern Asia. Paris is notable in China for its medicinal value. An investigation was conducted to determine the variations of 27 morphological characters of 196 accessions from 8 populations of medicinal Paris ...

  7. L2 listening at work

    DEFF Research Database (Denmark)

    Øhrstrøm, Charlotte

    This dissertation on adult second language (L2) learning investigates individual learners’ experiences with listening in Danish as an L2 in everyday situations at work. More specifically, the study explores when international employees, who work at international companies in Denmark with English...... as a corporate language, listen in Danish at work, how they handle these situations, what problems they experience, and why some situations are more difficult to listen in than others. The study makes use of qualitative research methods and theoretical aspects from psycholinguistic approaches as well as socially...

  8. Multimedia Glosses and Their Effect on L2 Text Comprehension and Vocabulary Learning

    Directory of Open Access Journals (Sweden)

    Iñigo Yanguas

    2009-06-01

    Full Text Available The present study investigates the effects that different types of multimedia glosses, namely textual, pictorial, and textual + pictorial, have on text comprehension and vocabulary learning when the goal is exclusively comprehension of a computerized text. This study is based on the theoretical framework of attention, which maintains that attention is critical in the acquisition process of an L2 (Robinson, 1995; Schmidt, 1995, 2001; Tomlin and Villa, 1994. Ninety-four participants read a text under one of four gloss conditions while asked to think aloud. This study investigated whether any of the conditions promoted noticing and whether this noticing led to better comprehension of the text and learning of the target vocabulary words. Reading comprehension, recognition, and production measures were utilized in a pre-post test design. Results of quantitative and qualitative analyses of the data gathered showed first that all multimedia gloss groups noticed and recognized significantly more of the target words than the control group. Second, no significant differences were found among any of the groups in production of the target vocabulary items. Finally, regarding comprehension, results showed that the combination gloss group significantly outperformed all other groups. These results confirm that the multimedia glosses under investigation have a different effect on comprehension and vocabulary learning respectively.

  9. L2 English Intonation: Relations between Form-Meaning Associations, Access to Meaning, and L1 Transfer

    Science.gov (United States)

    Ortega-Llebaria, Marta; Colantoni, Laura

    2014-01-01

    Although there is consistent evidence that higher levels of processing, such as learning the form-meaning associations specific to the second language (L2), are a source of difficulty in acquiring L2 speech, no study has addressed how these levels interact in shaping L2 perception and production of intonation. We examine the hypothesis of whether…

  10. An Investigation into the Modality Specificity of L2 Learners' STM Abilities in Learning Vocabulary via PDAs

    Directory of Open Access Journals (Sweden)

    Saeed Khazaie

    2012-09-01

    Full Text Available Parallel with the rapid growth of wireless technology and potentials of mobile learning for language teaching/learning, employing mobile devices in language learning seems indispensable. To this end, designing learning materials suitable for different types of mobile devices regarding dual coding (DCT and cognitive load (CLT theories seems inevitable. In this study, multimedia were employed for designing two types of learning materials. Since short-term memory plays an important role in language learning, learners’ visual and verbal short-term memories were taken into consideration, too. 161 L2 Learners aged 19 and 23 years old participated in the major phases of an experiment via personal digital assistant (PDA. Based on their scores on the English vocabulary recognition and recall (EVRR tests and the statistical analysis of the results, it was revealed that delivery of learning materials with pictorial and written annotations combined rather than delivery of learning materials without such annotations to learners with high-visual and high-verbal abilities, learners with high-visual but low-verbal ability, and learners with low-visual but high-verbal ability results in better vocabulary learning outcomes. However, this was not the case for learners with low-visual and low-verbal abilities. This study acknowledges the relation between STM and the relevant modalities of materials presentation.

  11. Translation and Short-Term L2 Vocabulary Retention: Hindrance or Help?

    Science.gov (United States)

    Hummel, Kirsten M.

    2010-01-01

    This study addresses the role that active translation may have in second language (L2) vocabulary learning. Some research suggests that translation might be an effective cognitive strategy for L2 vocabulary learning. Participants were 191 native French-speaking students enrolled in a TESL (Teaching English as a Second Language) program.The study…

  12. L1-norm locally linear representation regularization multi-source adaptation learning.

    Science.gov (United States)

    Tao, Jianwen; Wen, Shiting; Hu, Wenjun

    2015-09-01

    In most supervised domain adaptation learning (DAL) tasks, one has access only to a small number of labeled examples from target domain. Therefore the success of supervised DAL in this "small sample" regime needs the effective utilization of the large amounts of unlabeled data to extract information that is useful for generalization. Toward this end, we here use the geometric intuition of manifold assumption to extend the established frameworks in existing model-based DAL methods for function learning by incorporating additional information about the target geometric structure of the marginal distribution. We would like to ensure that the solution is smooth with respect to both the ambient space and the target marginal distribution. In doing this, we propose a novel L1-norm locally linear representation regularization multi-source adaptation learning framework which exploits the geometry of the probability distribution, which has two techniques. Firstly, an L1-norm locally linear representation method is presented for robust graph construction by replacing the L2-norm reconstruction measure in LLE with L1-norm one, which is termed as L1-LLR for short. Secondly, considering the robust graph regularization, we replace traditional graph Laplacian regularization with our new L1-LLR graph Laplacian regularization and therefore construct new graph-based semi-supervised learning framework with multi-source adaptation constraint, which is coined as L1-MSAL method. Moreover, to deal with the nonlinear learning problem, we also generalize the L1-MSAL method by mapping the input data points from the input space to a high-dimensional reproducing kernel Hilbert space (RKHS) via a nonlinear mapping. Promising experimental results have been obtained on several real-world datasets such as face, visual video and object. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Negative evidence in L2 acquisition

    Directory of Open Access Journals (Sweden)

    Anne Dahl

    2005-02-01

    Full Text Available This article deals with the L2 acquisition of differences between Norwegian and English passives, and presents data to show that the acquisition of these differences by Norwegian L2 acquirers of English cannot be fully explained by positive evidence, cues, conservativism or economy. Rather, it is argued, it is natural to consider whether indirect negative evidence may facilitate acquisition by inferencing. The structures in focus are impersonal passive constructions with postverbal NPs and passive constructions with intransitive verbs. These sentences are ungrammatical in English. Chomsky (1981 proposes that this is a result of passive morphology absorbing objective case in English. There is no such case to be assigned to the postverbal NP in impersonal passives. In passive constructions with intransitive verbs, the verb does not assign objective case, so that there is no case for the passive morphology to absorb. Thus, impersonal passives have to be changed into personal passives, where the NP receives nominative case, and the objective case is free to go to the passive morphology. Intransitive verbs, however, cannot be used in the passive voice at all. Both the structures discussed in this article, i.e. are grammatical in Norwegian. However, the options available in English, viz. personal passives and active sentences, are equally possible. Åfarli (1992 therefore proposes that Norwegian has optional case absorption (passive morphology optionally absorbs case. On the basis on such observations, we may propose a parameter with the settings [+case absorption] for English, and [-case absorption], signifying optional case absorption, for Norwegian. This means that none of the structures that are grammatical in English can function as positive evidence for the [+case absorption] setting, since they are also grammatical in optional case absorption languages. The question is how this parameter is set.

  14. L2-proficiency-dependent laterality shift in structural connectivity of brain language pathways

    NARCIS (Netherlands)

    Xiang, H.; Leeuwen, T.M. van; Dediu, D.; Roberts, L.; Norris, D.; Hagoort, P.

    2015-01-01

    Diffusion tensor imaging (DTI) and a longitudinal language learning approach were applied to investigate the relationship between the achieved second language (L2) proficiency during L2 learning and the reorganization of structural connectivity between core language areas. Language proficiency tests

  15. L2-Proficiency-Dependent Laterality Shift in Structural Connectivity of Brain Language Pathways

    NARCIS (Netherlands)

    Xiang, Huadong; van Leeuwen, Tessa Marije; Dediu, Dan; Roberts, Leah; Norris, David G.; Hagoort, Peter

    2015-01-01

    Diffusion tensor imaging (DTI) and a longitudinal language learning approach were applied to investigate the relationship between the achieved second language (L2) proficiency during L2 learning and the reorganization of structural connectivity between core language areas. Language proficiency tests

  16. Personalized versus Normal Practice of L2 Speaking on Iranian EFL Learners’ Oral Proficiency

    Directory of Open Access Journals (Sweden)

    Ayda Rahmani

    2015-03-01

    Full Text Available Personalized learning is a self-initiated, self-directed or self-prioritized pursuit which gives the learner a degree of choice about the process of learning i.e. what to learn, how to learn and when to learn. Of course personalized learning does not indicate unlimited choice; because, L2 learners will still have targets to be met. However, it provides learners with the opportunity to learn in ways that suit their individual learning styles. The L2 learner should have the opportunity to freely choose a series of activities, already predisposed by the teacher, to improve and develop L2 proficiency. This is because human beings have different ways to learn and process information; and, these different ways of learning are independent of each other. In other words, learning styles and techniques differ across individuals; thus, personalized learning provides L2 learners to freely choose the activities they enjoy the most. So it is a student-centered learning method in which the interests and the preferences of the learner is taken into account.The present study is an investigation of a personalized versus normal practice of L2 proficiency. For this purpose an OPT (Oxford Placement Test was given to a total of 80 Iranian EFL learners. Then, 40 of them who were considered as intermediate learners were selected for the purpose of the study. The participants were randomly divided into two groups i.e. an experimental group and a control group. Both groups were pretested prior to the study. Then, the experimental group received the treatment in the form of personalized learning (games-based learning, songs, music, stories, English tongue twisters and the materials that the subjects were most interested in for ten sessions while the control group received a normal practice of speaking proficiency (based on New Interchange course books. After ten sessions, both groups were post tested. Then the results of the posttests were subjects of statistical analysis

  17. A Brief Analysis of L2 Motivation

    Institute of Scientific and Technical Information of China (English)

    武曼

    2017-01-01

    Learning motivation is the motility to urge the student to be engaged in the studies activity. This thesis has introduced types of L2 learning motivation. Through the contrast and analysis about the positive motivation and negative motivation in prac?tical applications, this paper has indicated the unique of positive motivation and the defects of negative motivation, and make rea?sonable suggestions.

  18. Negative Transfer of L1 on English Grammar Learning in SLA

    Institute of Scientific and Technical Information of China (English)

    马秀琳

    2015-01-01

    At present,many scholars pay more attention to the positive transfer of native language on the English learning,while ignoring the negative transfer of L1 on English grammar learning.Therefore native transfer of L1 often appears on English grammar learning.This paper aims to point out that the negative transfer of L1 has a profound and vast influence on the English grammar learning,to find out the countermeasures to reduce the influence of negative transfer of L1 and finally to bring the benefits to the following relative studies.

  19. Making Room for Second Language Phonotactics: Effects of L2 Learning and Environment on First Language Speech Perception.

    Science.gov (United States)

    Carlson, Matthew T

    2018-04-01

    Language-specific restrictions on sound sequences in words can lead to automatic perceptual repair of illicit sound sequences. As an example, no Spanish words begin with /s/-consonant sequences ([#sC]), and where necessary (e.g., foreign loanwords) [#sC] is repaired by inserting an initial [e], (e.g. foreign loanwords, cf., esnob, from English snob). As a result, Spanish speakers tend to perceive an illusory [e] before [#sC] sequences. Interestingly, this perceptual illusion is weaker in early Spanish-English bilinguals, whose other language, English, allows [#sC]. The present study explored whether this apparent influence of the English language on Spanish is restricted to early bilinguals, whose early language experience includes a mixture of both languages, or whether later learning of second language (L2) English can also induce a weakening of the first language (L1) perceptual illusion. Two groups of late Spanish-English bilinguals, immersed in Spanish or English, were tested on the same Spanish AX (same-different) discrimination task used in a study by Carlson et al., (2016) and their results compared with the Spanish monolinguals from Carlson et al.'s study. Like early bilinguals, late bilinguals exhibited a reduced impact of perceptual prothesis on discrimination accuracy. Additionally, late bilinguals, particularly in English immersion, were slowest when responding against the Spanish perceptual illusion. Robust L1 perceptual illusions thus appear to be malleable in the face of later L2 learning. It is argued that these results are consonant with the need for late bilinguals to navigate alternative, conflicting representations of the same acoustic material, even in unilingual L1 speech perception tasks.

  20. Could a Multimodal Dictionary Serve as a Learning Tool? An Examination of the Impact of Technologically Enhanced Visual Glosses on L2 Text Comprehension

    Science.gov (United States)

    Sato, Takeshi

    2016-01-01

    This study examines the efficacy of a multimodal online bilingual dictionary based on cognitive linguistics in order to explore the advantages and limitations of explicit multimodal L2 vocabulary learning. Previous studies have examined the efficacy of the verbal and visual representation of words while reading L2 texts, concluding that it…

  1. Using interactive multimedia e-Books for learning blood cell morphology in pediatric hematology.

    Science.gov (United States)

    Hsiao, Chih-Cheng; Tiao, Mao-Meng; Chen, Chih-Cheng

    2016-11-14

    This prospective study compares the use of interactive multimedia eBooks (IME) with traditional PowerPoint (TPP) for teaching cell morphology of blood and bone marrow. Fifty-one interns from three Taiwan medical schools training by a single teacher in the pediatric hematology department of Kaohsiung Chang Gung Memorial Hospital, Taiwan, participated in this study. 25 interns were allocated for training with a traditional PowerPoint atlas and 26 interns for training with an interactive multimedia eBook atlas. Learning outcomes were examined by pre-test and post-test using the CellQuiz of CellAtlas App. Attitudes and perceptions were collected by survey questions regarding interest, motivation and effectiveness. There was no difference in the pre-test scores between TPP and IME groups (mean score 27.0 versus 27.9, p = 0.807). However, the interns in the interactive multimedia eBook group achieved significantly better scores in the post-test than the ones in the PowerPoint group (mean score 103.2 versus 70.6; p < 0.001). Overall results of interest, motivation and effectiveness were strongly positive in the multimedia eBook group. Our data supports that interactive multimedia eBooks are more effective than PowerPoint to facilitate learning of cell morphology of blood and bone marrow.

  2. First report and morphological redescription of Teleonemia morio (Stål (Hemiptera, Tingidae in Annona squamosa L. (Annonaceae in Brazil

    Directory of Open Access Journals (Sweden)

    Sônia M. F. Broglio

    2012-03-01

    Full Text Available First report and morphological redescription of Teleonemia morio (Stål (Hemiptera, Tingidae in Annona squamosa L. (Annonaceae in Brazil. This is the first report of a severe attack of Teleonemia morio (Stål, 1855 (Hemiptera, Heteroptera, Tingidae on Annona squamosa L. (custard apple, causing up to 80% of losses of infested trees. In order to facilitate the identification of this insect pest, the adult female of T. morio is redescribed based on specimens collected in Palmeira dos Índios, Alagoas, Brazil.

  3. MORPHOLOGICAL AND ANATOMICAL STUDY OF THE GRASS OF VERONICA SPICATA L.

    Directory of Open Access Journals (Sweden)

    A. V. Kovalyova

    2015-01-01

    Full Text Available The article presents the results of morphological and anatomical studies of Veronica spicata L. Macro- and microscopic features of the grass of Veronica spicata were described. We have determined the principal diagnostic features of leaves and stems of the plant’s active parts. We have found two types of trichomes in active parts of Veronica spicata L.: simple pluricellular fuzz and cephalated glandular fuzz with monocellular pedicle and monocellular or bicellular sphere-like capitulum, anomcytic stomatal apparatus.

  4. Genetic diversity among Juglans regia L. genotypes assessed by morphological traits and microsatellite markers

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoodi, R.; Rahmani, F.; Rezaee, R.

    2013-06-01

    In this study, genetic diversity was assayed among 16 accessions and five cultivars of Persian walnut (Juglans regia L.) using morphological traits and nine simple sequence repeat (SSR) markers. Samples were collected from Agriculture Research Center of Urmia city (North West Iran). Study on important morphological traits revealed genetic similarity of -0.6 to 0.99 based on CORR coefficient. The microsatellite marker system produced 34 alleles in range of 160-290 bp. The minimum (2) and maximum (7) number of alleles were obtained from WGA71 and WGA202 genetic loci, respectively. The mean number of alleles per locus was 4.25. Jaccards similarity coefficient ranged from 0.13 to 0.76. The results of this paper indicate high diversity among these genotypes which could be used for breeding management. (Author) 28 refs.

  5. Morphological and chemical variability of Ocimum basilicum L. (Lamiaceae

    Directory of Open Access Journals (Sweden)

    Renata Nurzyńska-Wierdak

    2013-04-01

    Full Text Available Morphological features of 17 sweet basil cultivars as well as essential oil content and composition were determined. The study clearly indicated great variability of Ocimum basilicumL. The content of essential oil in the dried herb was high and varied from 0.75% (O. basilicumvar. piperita to 1.89% (O. basilicumvar. cinnamon. Based of the primary components, three chemotypes were distinguished: citral (‘Lime’, ‘Lemon’ and var. citriodorum, E-methyl cinnamate/linalool (‘Licorice’, var. cinnamon and methyl chavicol (‘Tai’.

  6. Intro til Learning Analytics & datainformeret undervisning og læring

    DEFF Research Database (Denmark)

    Ringtved, Ulla Lunde

    Introduktion til Learning Analytics – Modeller og eksempler fra forskningsfeltet Learning Analytics. Data fra ny opgavetyper, ny kompetencer, nyt læringsudbytte. Nye Målemetoder – Hvad er det vi vil måle – Hvordan viser vi det?......Introduktion til Learning Analytics – Modeller og eksempler fra forskningsfeltet Learning Analytics. Data fra ny opgavetyper, ny kompetencer, nyt læringsudbytte. Nye Målemetoder – Hvad er det vi vil måle – Hvordan viser vi det?...

  7. Suggestions of keeping L2 motivation

    Institute of Scientific and Technical Information of China (English)

    徐斌

    2014-01-01

    How will we keep the motivation during the second language as long as we can, which confuses us, though what the L2 motivation is and how it is developed have been discussed by the psychologists, educators, etc. The aim of this passage is to clarify the basic content of motivation, including the definition, classification, importance, etc. how the current situation is in se-nior high students’English learning motivation, what should be done to keep such motivation. In the following part, it will be read that the introduction, the chapter stating the content and classification of (L 2) motivation, the chapter analyzing the necessity and state of L2 motivation at senor high, the chapter offering approach to keep that motivation, and the conclusion. All of them use the comparison, explanation and cites.

  8. Three-dimensional printing model improves morphological understanding in acetabular fracture learning: A multicenter, randomized, controlled study.

    Directory of Open Access Journals (Sweden)

    Zhenfei Huang

    Full Text Available Conventional education results in unsatisfactory morphological understanding of acetabular fractures due to lack of three-dimensional (3D details and tactile feedback of real fractures. Virtual reality (VR and 3D printing (3DP techniques are widely applied in teaching. The purpose of this study was to identify the effect of physical model (PM, VR and 3DP models in education of morphological understanding of acetabular fractures. 141 students were invited to participate in this study. Participants were equally and randomly assigned to the PM, VR and 3DP learning groups. Three-level objective tests were conducted to evaluate learning, including identifying anatomical landmarks, describing fracture lines, identifying classification, and inferring fracture mechanism. Four subjective questions were asked to evaluate the usability and value of instructional materials. Generally, the 3DP group showed a clear advantage over the PM and VR groups in objective tests, while there was no significant difference between the PM and VR groups. 3DP was considered to be the most valuable learning tool for understanding acetabular fractures. The findings demonstrate that 3DP modelling of real fractures is an effective learning instrument that can be used to understand the morphology of acetabular fractures and promote subjective interest.

  9. Learning English Tenses through Spanish Grammar : When Using the L1 Benefits ESL Learning

    OpenAIRE

    López Garrido, Ramon

    2016-01-01

    The current teaching trend of ESL is focused on maximizing the use of the L2 so that the student learns the language through linguistic immersion. This approach leaves the L1 out of the game, even though research has shown it can also be beneficial for the learner. My research intends to demonstrate that translation of English grammar tenses into Spanish can be a helpful way of assimilating English grammar more easily and faster, especially for those students with a poor command of English. ...

  10. Beyond barriers : Complexity, accuracy, and fluency in long-term L2 speakers' speech

    NARCIS (Netherlands)

    Lahmann, Cornelia Milli Marie Antonia

    2015-01-01

    It remains to be a puzzling question why some people are more successful in learning a second language (L2) than others and under which conditions. In my dissertation I studied the effects of several factors, including the starting age of learning a L2, the amount of continued exposure to the first

  11. Learning second language vocabulary: neural dissociation of situation-based learning and text-based learning.

    Science.gov (United States)

    Jeong, Hyeonjeong; Sugiura, Motoaki; Sassa, Yuko; Wakusawa, Keisuke; Horie, Kaoru; Sato, Shigeru; Kawashima, Ryuta

    2010-04-01

    Second language (L2) acquisition necessitates learning and retrieving new words in different modes. In this study, we attempted to investigate the cortical representation of an L2 vocabulary acquired in different learning modes and in cross-modal transfer between learning and retrieval. Healthy participants learned new L2 words either by written translations (text-based learning) or in real-life situations (situation-based learning). Brain activity was then measured during subsequent retrieval of these words. The right supramarginal gyrus and left middle frontal gyrus were involved in situation-based learning and text-based learning, respectively, whereas the left inferior frontal gyrus was activated when learners used L2 knowledge in a mode different from the learning mode. Our findings indicate that the brain regions that mediate L2 memory differ according to how L2 words are learned and used. Copyright 2009 Elsevier Inc. All rights reserved.

  12. Seed morphology of Iberian species of the genus Aconitum L.

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    Molero, Julià

    1990-12-01

    Full Text Available A biometric-morphological study of' the seeds of the taxons of the genus Aconitum L. occurring in the Iberian peninsula is given. The following features are treated: 1 arrangement of the seeds on the follicle, 2 definition of the parameters (general shape and ornamentation of the episperm, 3 biometry, and 4 description of the seeds of the Iberian taxa. Microcharacteristics related to the seed coat, shape and ornamentation or the insertion base (hilum and surrounding cells have been found most useful in differentiating the taxa; furthermore, they may provide more phylogenetic information than other features. The results given agree generally with those reported by other authors (Seitz, 1969; Cappeleti & Poldini, 1984 but some important discrepancies have been noted with reference to seminal morphology, particularly episperm ornamentation in the species A. anthora. A. napellus s.l., A. burnatii and A. vulparia subsp. ranunculifolium. Seminal polymorphism is frequently observed in different geographically isolated colonies or the same species or subspecies. both in the Iberian Peninsula and in Central and Southern Europe. We conclude that polymorphism is further evidence of the phenotypical flexibility of this genus, probably owing to genetic drift in the populations. This flexibility is particularly important in colonizing species or wide ecological valence (A . napellus, s. l.; A. vulparia s.l..

    [ca] Es presenta un estudi morfològica-biomètric de les granes dels tàxons del gènere Aconitum L. presents a la Península Ibèrica. Es tracten aspectes que fan referència a: 1 disposició de les granes al fol-licle. 2 definició de paràmetres (forma general i ornamentació de l'episperma, 3 biometria i 4 descripció de les granes dels representants ibèrics. Els microcaràcters relacionats fonamentalment amb el relleu epispèrmic, forma i ornamentació de la base d'inserció (hílum i

  13. Using interactive multimedia e-Books for learning blood cell morphology in pediatric hematology

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    Chih-Cheng Hsiao

    2016-11-01

    Full Text Available Abstract Background This prospective study compares the use of interactive multimedia eBooks (IME with traditional PowerPoint (TPP for teaching cell morphology of blood and bone marrow. Methods Fifty-one interns from three Taiwan medical schools training by a single teacher in the pediatric hematology department of Kaohsiung Chang Gung Memorial Hospital, Taiwan, participated in this study. 25 interns were allocated for training with a traditional PowerPoint atlas and 26 interns for training with an interactive multimedia eBook atlas. Learning outcomes were examined by pre-test and post-test using the CellQuiz of CellAtlas App. Attitudes and perceptions were collected by survey questions regarding interest, motivation and effectiveness. Results There was no difference in the pre-test scores between TPP and IME groups (mean score 27.0 versus 27.9, p = 0.807. However, the interns in the interactive multimedia eBook group achieved significantly better scores in the post-test than the ones in the PowerPoint group (mean score 103.2 versus 70.6; p < 0.001. Overall results of interest, motivation and effectiveness were strongly positive in the multimedia eBook group. Conclusions Our data supports that interactive multimedia eBooks are more effective than PowerPoint to facilitate learning of cell morphology of blood and bone marrow.

  14. The L2 Passionate Interactional Imperative (for short “The L2 Pie”: It’s Hot or It’s Not!

    Directory of Open Access Journals (Sweden)

    Tim Murphey

    2011-06-01

    Full Text Available At the American Association of Applied Linguistics (AAAL 2011 conference, John Schumann described how Lee, Dina, Joaquin, Mates & Schumann’s (2010 interactional instinct unfolds between infants and caregivers such that learning an L1 is assured in normal development through emotional bonding between infants and caregivers which is substantiated by motivation, proficiency, and opportunities (all co-constructing concepts. In subsequent second language learning at an older age, these three characteristics are not environmentally and contextually assured, and this seems to account for a great part of the shortcomings of much of the late-L2 instruction in the world (Lee, Dina, Joaquin, Mates & Schumann, 2010.

  15. Effects of input properties, vocabulary size, and L1 on the development of third person singular –s in child L2 English

    NARCIS (Netherlands)

    Blom, W.B.T.|info:eu-repo/dai/nl/140893261; Paradis, J.; Sorenson Duncan, T.

    2012-01-01

    This study was designed to investigate the development of third-person singular (3SG) –s in children who learn English as a second language (L2). Adopting the usage-based perspective on the learning of inflection, we analyzed spontaneous speech samples collected from 15 English L2 children who were

  16. Numerical morphology supports early number word learning: Evidence from a comparison of young Mandarin and English learners

    Science.gov (United States)

    Corre, Mathieu Le; Li, Peggy; Huang, Becky H.; Jia, Gisela; Carey, Susan

    2016-01-01

    Previous studies showed that children learning a language with an obligatory singular/plural distinction (Russian and English) learn the meaning of the number word for one earlier than children learning Japanese, a language without obligatory number morphology (Barner, Libenson, Cheung, & Takasaki, 2009; Sarnecka, Kamenskaya, Yamana, Ogura, & Yudovina, 2007). This can be explained by differences in number morphology, but it can also be explained by many other differences between the languages and the environments of the children who were compared. The present study tests the hypothesis that the morphological singular/plural distinction supports the early acquisition of the meaning of the number word for one by comparing young English learners to age and SES matched young Mandarin Chinese learners. Mandarin does not have obligatory number morphology but is more similar to English than Japanese in many crucial respects. Corpus analyses show that, compared to English learners, Mandarin learners hear number words more frequently, are more likely to hear number words followed by a noun, and are more likely to hear number words in contexts where they denote a cardinal value. Two tasks show that, despite these advantages, Mandarin learners learn the meaning of the number word for one three to six months later than do English learners. These results provide the strongest evidence to date that prior knowledge of the numerical meaning of the distinction between singular and plural supports the acquisition of the meaning of the number word for one. PMID:27423486

  17. Numerical morphology supports early number word learning: Evidence from a comparison of young Mandarin and English learners.

    Science.gov (United States)

    Le Corre, Mathieu; Li, Peggy; Huang, Becky H; Jia, Gisela; Carey, Susan

    2016-08-01

    Previous studies showed that children learning a language with an obligatory singular/plural distinction (Russian and English) learn the meaning of the number word for one earlier than children learning Japanese, a language without obligatory number morphology (Barner, Libenson, Cheung, & Takasaki, 2009; Sarnecka, Kamenskaya, Yamana, Ogura, & Yudovina, 2007). This can be explained by differences in number morphology, but it can also be explained by many other differences between the languages and the environments of the children who were compared. The present study tests the hypothesis that the morphological singular/plural distinction supports the early acquisition of the meaning of the number word for one by comparing young English learners to age and SES matched young Mandarin Chinese learners. Mandarin does not have obligatory number morphology but is more similar to English than Japanese in many crucial respects. Corpus analyses show that, compared to English learners, Mandarin learners hear number words more frequently, are more likely to hear number words followed by a noun, and are more likely to hear number words in contexts where they denote a cardinal value. Two tasks show that, despite these advantages, Mandarin learners learn the meaning of the number word for one three to six months later than do English learners. These results provide the strongest evidence to date that prior knowledge of the numerical meaning of the distinction between singular and plural supports the acquisition of the meaning of the number word for one. Copyright © 2016. Published by Elsevier Inc.

  18. Migrazioni virtuali: teletandem per l’apprendimento di una L2

    Directory of Open Access Journals (Sweden)

    Paola Leone

    2017-01-01

    Full Text Available Virtual migrations. Teletandem for second language learningTeletandem is included as an L2 learning context in different university degree courses throughout the world. It is a form of telecollaboration by which two students, proficient in two different languages, interact orally via Voice Over Internet Protocol (VOIP technology in order to develop their L2 competences. The current paper aims to describe a learning scenario based on teletandem as it is designed and experienced at the University of Salento. Together with teletandem sessions, the learning scenario includes different classroom tasks, performed collaboratively by students and teachers. For the tasks, video recordings of teletandem sessions are used. Students are asked to select parts of the conversation with their partner in order to discuss linguistic and cultural communicative problems. The whole learning scenario aims primarily to enhance students’ oral communication abilities (both in monologues and in interaction. The following topics are therefore discussed: the basic characteristics of teletandem interaction; digital resources used for the learning scenario; the role of the teacher as a mediator; and how mediation sessions are organized.

  19. Derivational morphology and Serbian EFL learners: Three perspectives on the acquisition process

    Directory of Open Access Journals (Sweden)

    Dimitrijević-Savić Jovana V.

    2011-01-01

    Full Text Available Although it has long been an under-researched topic in the field of applied linguistics, morphological knowledge is nowadays regarded as a key component of vocabulary acquisition. The past two decades have witnessed a proliferation of studies of both L1 and L2 learning contexts which shed light on various issues, ranging from morphological processing to receptive/productive knowledge of derivational and inflectional morphology. However, investigations into the acquisition of English morphology by Serbian EFL learners have, to our knowledge, been scarce. The purpose of this paper is, therefore, to explore the productive derivational knowledge of upper-intermediate Serbian EFL learners by means of three different instruments: a test focusing on the knowledge of the four main word family members (nouns, verbs, adjectives, adverbs, a test of cognate and non-cognate derivatives employing six cognate English-Serbian suffixes (-ous/-oz(an, -ize/-izovati, -ation/-acija -ism/-iz(am, -ist/-ist(a, -ity/-itet and a contextualized word-formation skill test. A combination of a qualitative and quantitative approach to data analysis has revealed the difficulties Serbian EFL learners have been experiencing in their morphology/vocabulary classes and it has enabled us to identify common mistakes and weak spots. Our results have pedagogical implications and could be put to use in curriculum design and methodology.

  20. Discussion: How different can perspectives on L2 development be?

    NARCIS (Netherlands)

    Hulstijn, J.H.

    2015-01-01

    In this article I discuss the contributions to this special issue of Language Learning on orders and sequences in second language (L2) development. Using a list of questions, I attempt to characterize what I see as the strengths, limitations, and unresolved issues in the approaches to L2 development

  1. Morphological distinction between estuarine polychaetes: Laeonereis culveri and L. nota (Phyllodocida: Nereididae).

    Science.gov (United States)

    de Jesus-Flores, Citlalli; Salazar-González, S Alejandro; Salazar-Vallejo, Sergio I

    2016-03-01

    The family Nereididae includes more than 500 polychaete species described worldwide, and includes species common in many benthic environments, but some other species may tolerate freshwater or can even thrive in humid substrates in tropical forests. In estuarine environments, nereidid polychaetes can be abundant and relevant as a food source for resident or migratory birds. Laeonereis culveri (Webster, 1879) is a common estuarine species found in tropical and subtropical Atlantic American shores and was described from New Jersey; its median and posterior parapodia have upper notopodial ligules usually longer than the lower ones, and the latter are parallel to the notaciculae throughout the body. L. culveri distribution is from Connecticut to central Argentina; however, this wide distribution might be due to the inclusion of several other species as junior synonyms, despite that some morphological differences were found between them. One of such species is L. nota (Treadwell, 1941), that was described from Texas; its parapodia have notopodial ligules of about the same size, and the lower ones are oblique to the notaciculae. In order to clarify the differences between these two species, and to define which inhabits the Northwestern Caribbean region, topotype materials from these two species and specimens from Chetumal Bay were collected, and their morphological features were compared. Our results indicated that L. culveri and L. nota are different species and that the latter is found in Chetumal Bay. On the basis of mature specimens, L. culveri is hereby restricted to the Northern Gulf of Mexico and Northwestern Atlantic Ocean, and L. nota are reinstated and its distribution extends from Texas, in the Gulf of Mexico to Chetumal Bay, in the Northwestern Caribbean Sea. A key to identify all species in Laeonereis Hartman (1945) is also included.

  2. Early literacy experiences constrain L1 and L2 reading procedures

    Directory of Open Access Journals (Sweden)

    Adeetee eBhide

    2015-10-01

    Full Text Available Computational models of reading posit that there are two pathways to word recognition, using sublexical phonology or morphological/orthographic information. They further theorize that everyone uses both pathways to some extent, but the division of labor between the pathways can vary. This review argues that the first language one was taught to read, and the instructional method by which one was taught, can have profound and long-lasting effects on how one reads, not only in one’s first language, but also in one’s second language. Readers who first learn a transparent orthography rely more heavily on the sublexical phonology pathway, and this seems relatively impervious to instruction. Readers who first learn a more opaque orthography rely more on morphological/orthographic information, but the degree to which they do so can be modulated by instructional method. Finally, readers who first learned to read a highly opaque morphosyllabic orthography use less sublexical phonology while reading in their second language than do other second language learners and this effect may be heightened if they were not also exposed to an orthography that codes for phonological units during early literacy acquisition. These effects of early literacy experiences on reading procedure are persistent despite increases in reading ability.

  3. Effects of plant densities on yield, yield components and some morphological characters of two cultivators of oilseed rape (Brassica napus L.)

    DEFF Research Database (Denmark)

    Al-Barzinjy, M.; Stölen, O.; Christiansen, Jørgen Lindskrog

    2003-01-01

    Effects of Plant Densities on Yield, Yield Components and some Morphological Characters of two Cultivators of Oilseed Rape (Brassica napus L.)......Effects of Plant Densities on Yield, Yield Components and some Morphological Characters of two Cultivators of Oilseed Rape (Brassica napus L.)...

  4. Acquiring native-like intonation in Dutch and Spanish : Comparing the L1 and L2 of native speakers and second language learners

    NARCIS (Netherlands)

    van Maastricht, L.J.; Swerts, M.G.J.; Krahmer, E.J.

    2013-01-01

    ACQUIRING NATIVE-LIKE INTONATION IN DUTCH AND SPANISH Comparing the L1 and L2 of native speakers and second language learners Introduction Learning more about the interaction between the native language (L1) and the target language (L2) has been the aim of many studies on second language acquisition

  5. CALL--Enhanced L2 Listening Skills--Aiming for Automatization in a Multimedia Environment

    Science.gov (United States)

    Mayor, Maria Jesus Blasco

    2009-01-01

    Computer Assisted Language Learning (CALL) and L2 listening comprehension skill training are bound together for good. A neglected macroskill for decades, developing listening comprehension skill is now considered crucial for L2 acquisition. Thus this paper makes an attempt to offer latest information on processing theories and L2 listening…

  6. Pollen morphology of Rhizophora L. in Peninsular Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Mohd-Arrabe' , A. B.; Noraini, Talip Noraini [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2013-11-27

    Rhizophora L. are common mangrove genus in Peninsular Malaysia, it contains 3 species and 1 hybrid (R. apiculata Blume, R. mucronata Lam., R. stylosa Griff., R. x lamarckii Montrouz). This genus has some unique adaptation towards extreme environment. Rhizophora has looping aerial stilt-root and uniformly viviparous. The aim of this study is to investigate the variation in the pollen morphology of Rhizophora that can be related to their habitat. Methods include in this study is pollen observation under light and acetolysis method under scanning electron microscope. Pollen type of Rhizophora species studied except hybrid species is classified tricolporate, shape spheroidal based on ratio of length polar axis/ length of equatorial axis (1.03 - 1.09). The exine ornamentation is perforate-reticulate for R. apiculata and R. mucronata, while R. stylosa is perforate. For the only hybrid in Peninsular Malaysia, R. x lamarckii (R. apiculata x R. stylosa) differs from others, tricolpate with the absence of porate, shape is subprolate and exine ornamentation is reticulate and striate in equatorial region. Pollenkitt is present due to the salty and extreme environment. This may enhance the volume of pollenkitt present surrounding the pollen grains in Rhizophora for protection and adaptation purposes. Based on these findings, it is evident that pollen morphology is somehow related to its natural habitat.

  7. Pollen morphology of Rhizophora L. in Peninsular Malaysia

    International Nuclear Information System (INIS)

    Mohd-Arrabe', A. B.; Noraini, Talip Noraini

    2013-01-01

    Rhizophora L. are common mangrove genus in Peninsular Malaysia, it contains 3 species and 1 hybrid (R. apiculata Blume, R. mucronata Lam., R. stylosa Griff., R. x lamarckii Montrouz). This genus has some unique adaptation towards extreme environment. Rhizophora has looping aerial stilt-root and uniformly viviparous. The aim of this study is to investigate the variation in the pollen morphology of Rhizophora that can be related to their habitat. Methods include in this study is pollen observation under light and acetolysis method under scanning electron microscope. Pollen type of Rhizophora species studied except hybrid species is classified tricolporate, shape spheroidal based on ratio of length polar axis/ length of equatorial axis (1.03 - 1.09). The exine ornamentation is perforate-reticulate for R. apiculata and R. mucronata, while R. stylosa is perforate. For the only hybrid in Peninsular Malaysia, R. x lamarckii (R. apiculata x R. stylosa) differs from others, tricolpate with the absence of porate, shape is subprolate and exine ornamentation is reticulate and striate in equatorial region. Pollenkitt is present due to the salty and extreme environment. This may enhance the volume of pollenkitt present surrounding the pollen grains in Rhizophora for protection and adaptation purposes. Based on these findings, it is evident that pollen morphology is somehow related to its natural habitat

  8. Web 2.0 and Second Language Learning: What Does the Research Tell Us?

    Science.gov (United States)

    Wang, Shenggao; Vasquez, Camilla

    2012-01-01

    This article reviews current research on the use of Web 2.0 technologies in second language (L2) learning. Its purpose is to investigate the theoretical perspectives framing it, to identify some of the benefits of using Web 2.0 technologies in L2 learning, and to discuss some of the limitations. The review reveals that blogs and wikis have been…

  9. Investigating an Innovative Computer Application to Improve L2 Word Recognition from Speech

    Science.gov (United States)

    Matthews, Joshua; O'Toole, John Mitchell

    2015-01-01

    The ability to recognise words from the aural modality is a critical aspect of successful second language (L2) listening comprehension. However, little research has been reported on computer-mediated development of L2 word recognition from speech in L2 learning contexts. This report describes the development of an innovative computer application…

  10. Morphology and In Vitro Behavior of Electrospun Fibrous Poly(D,L-lactic acid for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Toshihiro Inami

    2013-01-01

    Full Text Available This work describes the fabrication, optimization, and characterization of electrospun fibrous poly(D,L-lactic acid (PDLLA for biomedical applications. The influences of the polymer concentration of the electrospinning solution (5, 10, or 15 wt% and the solution flow rate (0.1, 0.5, 1.0, or 2.0 mL/h on the morphology of the obtained fibrous PDLLA were evaluated. The in vitro biocompatibility of two types of PDLLA, ester terminated PDLLA (PDLLA-R and carboxyl terminated PDLLA (PDLLA-COOH, was evaluated by monitoring apatite formation on samples immersed in Hanks’ balanced salt (HBS solution. 15 wt% polymer solution was the most beneficial for preparing a fibrous PDLLA structure. Meanwhile, no differences in morphology were observed for PDLLA prepared at various flow rates. Apatite precipitate is formed on both types of PDLLA only 1 day after immersion in HBS solution. After 7 days of immersion, PDLLA-COOH showed greater apatite formation ability compared with that of PDLLA-R, as measured by thin-film X-ray diffraction. The results indicated that the carboxyl group is effective for apatite precipitation in the body environment.

  11. Design of dialogic eLearning-to-learn: metalearning as pedagogical methodology

    DEFF Research Database (Denmark)

    Sorensen, Elsebeth Korsgaard

    2008-01-01

    This paper presents a perspective emphasising Meta learning (ML) as the most significant and pertinent feature for promoting a democratic, collaborative eLearning-to-Learn (eL2L) phenomenon in a global context. Through attempting to understand and clarify the powers of pedagogical design of global...... networked e Learning based on Learning-to-Learn (L2L), it makes a plea for L2L in a dialogic global learning context, offering a vision of global democratic citizens able to engage in critical dialogue with fellow learners. http://www.inderscience.com/search/index.php?action=record&rec_id=17675&prev...

  12. IMPARARE L’ITALIANO L2 CON LE CANZONI. UN CONTRIBUTO DIDATTICO

    Directory of Open Access Journals (Sweden)

    Elisabetta Mauroni

    2011-07-01

    Full Text Available Il presente contributo si inserisce nel filone degli studi che hanno messo in evidenza la potenziale ricchezza della canzone come strumento di facilitazione dell’apprendimento della L2, e come mezzo per l’approccio al testo letterario per studenti di italiano L1, additandone il carattere di attività particolarmente efficace e ‘consonante’ con una prospettiva umanistico-affettiva, comunicativa, nonché socio-costruttivista. In queste pagine sono presentate alcune attività didattiche (pensate ora per gli apprendenti di italiano L2, ora per gli studenti di italiano L1 formulate a partire da alcuni testi del cantautore Claudio Baglioni (Io sono qui, Le vie dei Colori, Bolero, Fammi andar via tratti dall’album Io sono qui, 1995, edizioni CBS. I testi qui didattizzati sono utilizzabili in diverse prospettive: grammaticale, lessicale, retorica, socio-culturale, ecc.; e per diversi livelli di competenza linguistica (L2: A1-C1; L1.     Learning italian l2 through song.  A didactic contribution   This article is part of a series of studies which focus on the potential richness of songs as tools for facilitating L2 learning, as well as being a way to approach literary texts for L1 Italian students, being a particularly effective activity from a humanistic-affective, communicative and socio-constructivist point of view.  A few didactic activities are presented (designed for L2 Italian learners, or for L1 Italian learners based on songs by Claudio Baglioni (Io sono qui, Le vie dei Colori, Bolero, Fammi andar via from the album Io sono qui, 1995, edizioni CBS.  The texts were adapted for diverse didactic uses: grammatical, lexical, rhetorical, socio-cultural, etc and for different levels of linguistic competence (L2: A1-C1, L1

  13. Review of Social Interaction and L2 Classroom Discourse

    DEFF Research Database (Denmark)

    aus der Wieschen, Maria Vanessa

    2015-01-01

    Social Interaction and L2 Classroom Discourse investigates interactional practices in L2 classrooms. Using Conversation Analysis, the book unveils the processes underlying the co-construction of mutual understanding in potential interactional troubles in L2 classrooms – such as claims...... taster sessions over foreign language classrooms in monolingual contexts to English as an Additional Language settings in a multilingual context. This variety of settings allows him to examine a range of verbal and non-verbal features of classroom interaction, for example how code-switching is used......-6), and application (Chapters 7 and 8). A central focus throughout the entire book is classroom interactional competence and its influence on language learning....

  14. How new L2 words (don't) become memories : Lexicalization in advanced L1 Dutch learners of L2 English as part of a longitudinal study

    NARCIS (Netherlands)

    Keijzer, Merel

    It is an undisputed fact that learning – and remembering – new words is key in successful second language acquisition. And yet researching how vocabulary acquisition takes place is one of the most difficult endeavors in second language acquisition. We can test how many L2 words a learner knows, but

  15. Genetic relatedness among Solanum L. species assayed by seed morphology and isozyme markers

    International Nuclear Information System (INIS)

    Ahmed, S.M.; Fadl, M.A.

    2016-01-01

    In spite of their economic and medicinal value, no adequate attention has been paid to the diversity, characterization and taxonomical identification of Solanum L. species in Saudi Arabia. In this study, Scanning Electron Microscopy (SEM) of seed coat morphology and isozyme electrophoresis were employed for studying the genetic variability and relationships among seven Solanum L. species namely; S. incanum L., S. nigrum L., S. villosum L., S. schemprianum Hochst, S. galabratum Dunal, S. lycopersicum L. and S. melongena L. collected from Taif highlands. Scanning Electron Microscope (SEM) investigation of seed coat sculpturing showed three basic patterns namely; rugulate, reticulate and levigate. The analyses on six enzymes were coded by 19 loci. The number of alleles ranged from one to three with a mean of 1.58 alleles per locus. The proportion of polymorphic loci for Solanum L. species ranged from 0.87 for S. nigrum L. and S. villosum L. to 0.80 for S. lycopersicum L. The mean observed heterozygosity varied from 0.00 to 1.00, while mean expected heterozygosity ranged between 0.00 and 0.5. The UPGMA phenogram confirmed the extensive genetic diversity existed in the studied Solanum L. species and showed the close relationship between S. incanum L. and S. melongena L. (author)

  16. GOODS-HERSCHEL AND CANDELS: THE MORPHOLOGIES OF ULTRALUMINOUS INFRARED GALAXIES AT z ∼ 2

    International Nuclear Information System (INIS)

    Kartaltepe, Jeyhan S.; Dickinson, Mark; Alexander, David M.; Bell, Eric F.; Dahlen, Tomas; Lotz, Jennifer; Elbaz, David; Wiklind, Tommy; Faber, S. M.; Aussel, Herve; Bethermin, Matthieu; Bournaud, Frederic; Dannerbauer, Helmut; McIntosh, Daniel H.; Altieri, Bruno; Charmandaris, Vassilis; Conselice, Christopher J.; Cooray, Asantha; Davé, Romeel; Dunlop, James

    2012-01-01

    Using deep 100 and 160 μm observations in GOODS-South from GOODS-Herschel, combined with high-resolution HST/WFC3 near-infrared imaging from CANDELS, we present the first detailed morphological analysis of a complete, far-infrared (FIR) selected sample of 52 ultraluminous infrared galaxies (ULIRGs; L IR > 10 12 L ☉ ) at z ∼ 2. We also make use of a comparison sample of galaxies with lower IR luminosities but with the same redshift and H-band magnitude distribution. Our visual classifications of these two samples indicate that the fractions of objects with disk and spheroid morphologies are roughly the same but that there are significantly more mergers, interactions, and irregular galaxies among the ULIRGs (72 +5 –7 % versus 32 ± 3%). The combination of disk and irregular/interacting morphologies suggests that early-stage interactions, minor mergers, and disk instabilities could play an important role in ULIRGs at z ∼ 2. We compare these fractions with those of a z ∼ 1 sample selected from GOODS-H and COSMOS across a wide luminosity range and find that the fraction of disks decreases systematically with L IR while the fraction of mergers and interactions increases, as has been observed locally. At comparable luminosities, the fraction of ULIRGs with various morphological classifications is similar at z ∼ 2 and z ∼ 1, though there are slightly fewer mergers and slightly more disks at higher redshift. We investigate the position of the z ∼ 2 ULIRGs, along with 70 z ∼ 2 LIRGs, on the specific star formation rate versus redshift plane, and find 52 systems to be starbursts (i.e., they lie more than a factor of three above the main-sequence relation). We find that many of these systems are clear interactions and mergers (∼50%) compared to only 24% of systems on the main sequence relation. If irregular disks are included as potential minor mergers, then we find that up to ∼73% of starbursts are involved in a merger or interaction at some level

  17. GOODS-HERSCHEL AND CANDELS: THE MORPHOLOGIES OF ULTRALUMINOUS INFRARED GALAXIES AT z {approx} 2

    Energy Technology Data Exchange (ETDEWEB)

    Kartaltepe, Jeyhan S.; Dickinson, Mark [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Alexander, David M. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Dahlen, Tomas; Lotz, Jennifer [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Elbaz, David; Wiklind, Tommy [Joing ALMA Observatory, ESO, Santiago (Chile); Faber, S. M.; Aussel, Herve; Bethermin, Matthieu; Bournaud, Frederic; Dannerbauer, Helmut [Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu-CNRS-Universite Paris Diderot, CE-Saclay, F-91191 Gif-sur-Yvette (France); McIntosh, Daniel H. [University of California Observatories/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Altieri, Bruno [Herschel Science Centre, European Space Astronomy Centre, Villanueva de la Canada, E-28691 Madrid (Spain); Charmandaris, Vassilis [Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, GR-71003 Heraklion (Greece); Conselice, Christopher J. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Cooray, Asantha [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Dave, Romeel [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Dunlop, James, E-mail: jeyhan@noao.edu [Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); and others

    2012-09-20

    Using deep 100 and 160 {mu}m observations in GOODS-South from GOODS-Herschel, combined with high-resolution HST/WFC3 near-infrared imaging from CANDELS, we present the first detailed morphological analysis of a complete, far-infrared (FIR) selected sample of 52 ultraluminous infrared galaxies (ULIRGs; L{sub IR} > 10{sup 12} L{sub Sun }) at z {approx} 2. We also make use of a comparison sample of galaxies with lower IR luminosities but with the same redshift and H-band magnitude distribution. Our visual classifications of these two samples indicate that the fractions of objects with disk and spheroid morphologies are roughly the same but that there are significantly more mergers, interactions, and irregular galaxies among the ULIRGs (72{sup +5}{sub -7}% versus 32 {+-} 3%). The combination of disk and irregular/interacting morphologies suggests that early-stage interactions, minor mergers, and disk instabilities could play an important role in ULIRGs at z {approx} 2. We compare these fractions with those of a z {approx} 1 sample selected from GOODS-H and COSMOS across a wide luminosity range and find that the fraction of disks decreases systematically with L{sub IR} while the fraction of mergers and interactions increases, as has been observed locally. At comparable luminosities, the fraction of ULIRGs with various morphological classifications is similar at z {approx} 2 and z {approx} 1, though there are slightly fewer mergers and slightly more disks at higher redshift. We investigate the position of the z {approx} 2 ULIRGs, along with 70 z {approx} 2 LIRGs, on the specific star formation rate versus redshift plane, and find 52 systems to be starbursts (i.e., they lie more than a factor of three above the main-sequence relation). We find that many of these systems are clear interactions and mergers ({approx}50%) compared to only 24% of systems on the main sequence relation. If irregular disks are included as potential minor mergers, then we find that up to {approx

  18. The production and processing of determiner-noun agreement in child L2 Dutch

    NARCIS (Netherlands)

    Blom, E.; Vasić, N.

    2011-01-01

    Recent research has shown that children who learn Dutch as their second language (L2) have difficulties with Dutch grammatical gender. This study shows that six to nine year old L2 Dutch children whose first language (L1) is Turkish noticed incorrect gender agreement between determiner and noun only

  19. MyGfL: A Lifelong Learning Platform for Malaysian Society

    Science.gov (United States)

    Arabee Abdul Salam, Zailan; Mansur, Azmi

    2006-01-01

    MyGfL which stands for Malaysian Grid for Learning is a One-Stop-Center for quality assured online learning content, tools and services with the aim to promote and support the lifelong learning agenda in Malaysia. It is a platform that enables anyone to learn, unlearn and relearn from anywhere at anytime through any web browser so as to accelerate…

  20. Lexical and semantic representations of L2 cognate and noncognate words acquisition in children : evidence from two learning methods

    OpenAIRE

    Comesaña, Montserrat; Soares, Ana Paula; Sánchez-Casas, Rosa; Lima, Cátia

    2012-01-01

    How bilinguals represent words in two languages and which mechanisms are responsible for second language acquisition are important questions in the bilingual and vocabulary acquisition literature. This study aims to analyze the effect of two learning methods (picture-based vs. word-based method) and two types of words (cognates and noncognates) in early stages of children’s L2 acquisition. Forty-eight native speakers of European Portuguese, all sixth graders (mean age= 10.87 years; SD= 0....

  1. Lexical representation of novel L2 contrasts

    Science.gov (United States)

    Hayes-Harb, Rachel; Masuda, Kyoko

    2005-04-01

    There is much interest among psychologists and linguists in the influence of the native language sound system on the acquisition of second languages (Best, 1995; Flege, 1995). Most studies of second language (L2) speech focus on how learners perceive and produce L2 sounds, but we know of only two that have considered how novel sound contrasts are encoded in learners' lexical representations of L2 words (Pallier et al., 2001; Ota et al., 2002). In this study we investigated how native speakers of English encode Japanese consonant quantity contrasts in their developing Japanese lexicons at different stages of acquisition (Japanese contrasts singleton versus geminate consonants but English does not). Monolingual English speakers, native English speakers learning Japanese for one year, and native speakers of Japanese were taught a set of Japanese nonwords containing singleton and geminate consonants. Subjects then performed memory tasks eliciting perception and production data to determine whether they encoded the Japanese consonant quantity contrast lexically. Overall accuracy in these tasks was a function of Japanese language experience, and acoustic analysis of the production data revealed non-native-like patterns of differentiation of singleton and geminate consonants among the L2 learners of Japanese. Implications for theories of L2 speech are discussed.

  2. Shrinkage Degree in $L_{2}$ -Rescale Boosting for Regression.

    Science.gov (United States)

    Xu, Lin; Lin, Shaobo; Wang, Yao; Xu, Zongben

    2017-08-01

    L 2 -rescale boosting ( L 2 -RBoosting) is a variant of L 2 -Boosting, which can essentially improve the generalization performance of L 2 -Boosting. The key feature of L 2 -RBoosting lies in introducing a shrinkage degree to rescale the ensemble estimate in each iteration. Thus, the shrinkage degree determines the performance of L 2 -RBoosting. The aim of this paper is to develop a concrete analysis concerning how to determine the shrinkage degree in L 2 -RBoosting. We propose two feasible ways to select the shrinkage degree. The first one is to parameterize the shrinkage degree and the other one is to develop a data-driven approach. After rigorously analyzing the importance of the shrinkage degree in L 2 -RBoosting, we compare the pros and cons of the proposed methods. We find that although these approaches can reach the same learning rates, the structure of the final estimator of the parameterized approach is better, which sometimes yields a better generalization capability when the number of sample is finite. With this, we recommend to parameterize the shrinkage degree of L 2 -RBoosting. We also present an adaptive parameter-selection strategy for shrinkage degree and verify its feasibility through both theoretical analysis and numerical verification. The obtained results enhance the understanding of L 2 -RBoosting and give guidance on how to use it for regression tasks.

  3. L1 and L2 Picture Naming in Mandarin-English Bilinguals: A Test of Bilingual Dual Coding Theory

    Science.gov (United States)

    Jared, Debra; Poh, Rebecca Pei Yun; Paivio, Allan

    2013-01-01

    This study examined the nature of bilinguals' conceptual representations and the links from these representations to words in L1 and L2. Specifically, we tested an assumption of the Bilingual Dual Coding Theory that conceptual representations include image representations, and that learning two languages in separate contexts can result in…

  4. Language Play in Y2K: Morphology Brought to You by Pokemon.

    Science.gov (United States)

    Nilsen, Alleen Pace; Nilsen, Don L. F.

    2000-01-01

    Suggests that teachers can take advantage of children's interest in the Pokemon game to teach worthwhile lessons about how words are developed. Shows how, by analyzing Pokemon names, kids can learn the linguistic concept of morphology. (SR)

  5. Digital and traditional slides for teaching cellular morphology: a comparative analysis of learning outcomes.

    Science.gov (United States)

    Solberg, Brooke L

    2012-01-01

    Recent advances in technology have brought forth an intriguing new tool for teaching hematopoietic cellular identification skills: the digital slide. Although digitized slides offer a number of appealing options for educators, little research has been done to examine how their utilization would impact learning outcomes. To fill that void, this study was designed to examine student performance, skill retention and transferability, and self-efficacy beliefs amongst undergraduate MLS students learning cellular morphology with digital versus traditional slides. Results showed that students learning with digital slides performed better on assessments containing only traditional slide specimens than students learning with traditional slides, both immediately following the learning activity and after a considerable duration of time. Students learning with digital slides also reported slightly higher levels of self-efficacy related to cellular identification. The findings of this study suggest that students learning cellular identification skills with digital slides are able to transfer that skill directly to traditional slides, and that their ability to identify cells is not negatively affected in present or future settings.

  6. Using Multimedia Vocabulary Annotations in L2 Reading and Listening Activities

    Science.gov (United States)

    Jing Xu

    2010-01-01

    This paper reviews the role of multimedia vocabulary annotation (MVA) in facilitating second language (L2) reading and listening activities. It examines the multimedia learning and multimedia language learning theories that underlie the MVA research, synthesizes the findings on MVA in the last decade, and identifies three underresearched areas on…

  7. Studies on radiation induced morphological mutants in Sesamum orientale (L)

    International Nuclear Information System (INIS)

    Nayar, G.G.

    1970-01-01

    The agronomic characters of four X-ray induced morphological mutants in S. orientale L. viz. WFM, SSM isolated from var. T16 (back seeded) and SSM 2 and Chlo.mut.isolated from var. T10 (brown seeded) were studied. WFM, SSM and SSM 2 showed early sprouting and increased growth while the Chlo.mut. showed delayed germination and growth. The mean leaf size, plant height and number of branches were greater in WFM and SSM as compared to T16. The mean time of flowering was early in SSM and SSM 2 while it was late in WFM and the Chol.mut. as against their respective parents; the differences were significant. In mean yield of fruits per plant, WFM and SSM were superior to T16. A large scale trial has indicated that the seed yield in the mutants WFM, SSM and SSM 2 was slightly higher than their parents. WFM, SSM and SSM 2 showed an increase in oil content, the increase in SSM and SSM 2 being 6 to 10 percent. The quality of oil as indicated by colour and peroxide value (keeping quality) was also superior in WFM and SSM. The development of three flowers per node in SSM (otherwise solitary and axillary), two from modified nectary glands on either side of the leaf, provides some information on the phylogeny of the nectary glands and would appear to be of some economic significance. (author)

  8. Deconstructing Gender Stereotyping through Literature in L2

    Science.gov (United States)

    Yulita, Leticia

    2010-01-01

    While it is generally accepted that literature fosters (inter)cultural learning, few qualitative studies have sought to understand in what ways interculturality is developed. This article investigates the development of Spanish L2 students' intercultural awareness through the reading of a short story entitled "Norma y Ester" by Argentine…

  9. A Survey of tooth morphology teaching methods employed in the United Kingdom and Ireland.

    Science.gov (United States)

    Lone, M; McKenna, J P; Cryan, J F; Downer, E J; Toulouse, A

    2018-01-15

    Tooth morphology is a central component of the dental curriculum and is applicable to all dental specialities. Traditional teaching methods are being supplemented with innovative strategies to tailor teaching and accommodate the learning styles of the recent generation of students. An online survey was compiled and distributed to the staff involved in teaching tooth morphology in the United Kingdom and Ireland to assess the importance of tooth morphology in the dentistry curriculum and the methodologies employed in teaching. The results of the survey show that tooth morphology constitutes a small module in the dental curriculum. It is taught in the first 2 years of the dental curriculum but is applicable in the clinical years and throughout the dental career. Traditional teaching methods, lecture and practical, are being augmented with innovative teaching including e-learning via virtual learning environment, tooth atlas and e-books leading to blended learning. The majority of the schools teach both normal dental anatomy and morphologic variations of dental anatomy and utilise plastic teeth for practical and examination purposes. Learning the 3D aspects of tooth morphology was deemed important by most of the respondents who also agreed that tooth morphology is a difficult topic for the students. Despite being core to the dental curriculum, overall minimal time is dedicated to the delivery of tooth morphology, creating a reliance on the student to learn the material. New forms of delivery including computer-assisted learning tools should help sustain learning and previously acquired knowledge. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Functional and neurochemical profile of place learning after L-nitro-arginine in the rat

    DEFF Research Database (Denmark)

    Mogensen, Jesper; Wörtwein, Gitta; Hasman, Andreas

    1995-01-01

    Neurobiology, nitrogenoxid (NO), place learning, rotte, L-Nitro-Arginin, funktionel genopretning......Neurobiology, nitrogenoxid (NO), place learning, rotte, L-Nitro-Arginin, funktionel genopretning...

  11. Taxonomic significance of cypsela morphology for the tribe mutisieae (s.l.) (asteraceae) from Pakistan

    International Nuclear Information System (INIS)

    Abid, R.; Alam, J.

    2011-01-01

    Cypselas of 5 species distributed in 3 genera of the tribe Mutisieae (s.l.) were examined from Pakistan to assess their taxonomic significance. Micro morphological characters of cypsela including shape, pappus and carpopodium have been proved very rewarding to evaluate the taxonomic decisions both at the generic and specific levels. (author)

  12. Bridging Theory and Practice: Developing Lower-Level Skills in L2 Reading

    Science.gov (United States)

    Kato, Shigeo

    2012-01-01

    Studies on L2 reading have provided extensive evidence for the significant contribution of lower-level processing skills in learning to read and the critical impact on the overall development of L2 reading of more accurate and fluent connections between three sub-lexical components: phonology, orthography and semantics. The broad consensus among…

  13. A Vocabulary Learning Tool for L2 Undergraduates Reading Science and Technology Textbooks

    Science.gov (United States)

    Hsu, Chihcheng; Yang, Fang-Chuan Ou

    2013-05-01

    Students of English as a second language who major in science and technology use English-language textbooks to ensure that they can read English materials upon graduation. Research indicates that teachers spend little time helping these students on the linguistic complexity of such textbooks. Vocabulary, grammar, and article structure are elements of this complexity, but to many students, these elements can be akin to locked doors. This study presents MyVLS-Reader, which focuses on unlocking the first of these doors-vocabulary-while assisting in reading. With explicit vocabulary learning, students learn and memorize individual vocabulary, but the context is lost if the depth of learning discards context. In implicit vocabulary learning, students acquire vocabulary through repeated exposure to contexts, but repeated encounters with new words are required. Few e-learning systems combine both vocabulary-learning approaches. MyVLS-Reader achieves such synergy by (1) using a keyword setting to provide context-matched vocabulary explanation while reading and (2) embedding multiple learning choices, such as keyword setting, the review and memorization of explicit vocabulary, and the option to ask instructors. This study includes two rounds of evaluations: (1) an evaluation of the learning achievements of control and treatment groups and (2) a quantitative and qualitative investigation of perceptions regarding the use of MyVLS-Reader. The evaluation results indicate that the treatment group developed a better vocabulary than the control group in significantly less time. The use of MyVLS-Reader also slightly improved higher-order thinking skills. This result suggests that MyVLS-Reader can effective assist students in building their vocabulary while reading.

  14. Bariatric surgery, gut morphology and enteroendocrine cells

    DEFF Research Database (Denmark)

    Hansen, Carl Frederik

    40 hormones. In this PhD study, gut morphology and the population of endocrine cells have been examined in three rodent animal models using stereological techniques. First, in a rodent model of type-2 diabetes (T2DM), the Zucker diabetic fatty rat (ZDF), the population of endocrine L-cells...... to contribute to the positive effects of bariatic surgery but the mechanisms remain largely unknown. The endocrine cells of the gastrointestinal tract that produce and secrete hormones are difficult to examine as they are distributed as single cells. Several types of endocrine cells together produce more than...... and the gut morphology were quantified. The number of Lcells was 4.8 million in the normal rat and the L-cells were found to double in number in the diabetic ZDF rat model. Second, the L-cell population, gut morphology and endocrine cell gene expression were examined in a rodent model of Roux-en-Y gastric...

  15. First report and morphological redescription of Teleonemia morio (Stål (Hemiptera, Tingidae in Annona squamosa L. (Annonaceae in Brazil

    Directory of Open Access Journals (Sweden)

    Sônia M. F. Broglio

    2012-03-01

    Full Text Available First report and morphological redescription of Teleonemia morio (Stål (Hemiptera, Tingidae in Annona squamosa L. (Annonaceae in Brazil. This is the first report of a severe attack of Teleonemia morio (Stål, 1855 (Hemiptera, Heteroptera, Tingidae on Annona squamosa L. (custard apple, causing up to 80% of losses of infested trees. In order to facilitate the identification of this insect pest, the adult female of T. morio is redescribed based on specimens collected in Palmeira dos Índios, Alagoas, Brazil.Primeiro registro e redescrição morfológica de Teleonemia morio (Stål (Hemiptera, Tingidae em Annona squamosa L. (Annonaceae no Brazil. Este é o primeiro registro de um ataque severo de Teleonemia morio (Stål, 1855 (Hemiptera, Heteroptera, Tingidae em árvores de Annona squamosa L. (pinheira ou fruta-do-conde, resultando em perdas de aproximadamente 80% das plantas infestadas. Com o objetivo de facilitar a identificação deste inseto-praga, foi feita a redescrição da fêmea adulta de T. morio com base em espécimes coletados em Palmeira dos Índios, Alagoas, Brasil.

  16. The Implementation of Collaborative Learning Using AfL through Giving Feedback Strategy for Improving Students’ Attention to Mathematics Lesson

    Science.gov (United States)

    Kurniasih, R.; Sujadi, I.; Pramesti, G.

    2016-02-01

    This research aims to describe the process of implementation collaborative learning with AfL through giving feedback strategy for improving students’ attention to mathematics lesson. Data which is collected in this research are students’ attention towards learning and students’ achievement. The result of this research showed that the learning steps by using collaborative learning with AfL through giving feedback strategy which can improve students’ attention are: 1) pre activity: the teacher delivers the purpose of the learning, successful criteria, apperception, and motivation. 2) main activity: the teacher gives the background of learning activity, explains learning materials at a glance, divides students discuss, the teacher observes and guides students to the problem solving, present their discussion result, gives feedback, the students do AfL problem and the answer is collected and result will be given before next meeting. 3) post activity: the teacher with students concludes the material. Test result, the percentage of students who complete the examination in the second cycle is 77.27%. Based on those results can be concluded that the implementation of collaborative learning using AfL through giving feedback can improve students’ attention towards learning and students’ achievement of XI IPA Students MA Al-Islam Jamsaren Surakarta academic year 2013/2014.

  17. Analysis of Lamarckian Evolution in Morphologically Evolving Robots

    NARCIS (Netherlands)

    Jelisavcic, Milan; Kiesel, Rafael; Glette, Kyrre; Haasdijk, Evert; Eiben, A.E.

    Evolving robot morphologies implies the need for lifetime learning so that newborn robots can learn to manipulate their bodies. An individual’s morphology will obviously combine traits of all its parents; it must adapt its own controller to suit its morphology, and cannot rely on the controller of

  18. Selective Listening in L2 Learners of French

    Science.gov (United States)

    Graham, Suzanne; Santos, Denise

    2013-01-01

    This paper considers the issue raised in 2008 by Gillian Brown in her article "Selective listening" regarding whether nouns are "privileged" in memory over verbs during listening tasks, and whether attention to nouns, at least in the early stages of L2 learning, is a desirable strategy to be taught to learners, as Brown…

  19. E-Learning 2.0: Learning Redefined

    OpenAIRE

    Kumar, Rupesh

    2009-01-01

    The conventional e-learning approach emphasizes a learning system more than a learning environment. While traditional e-learning systems continue to be significant, there is a new set of services emerging, embracing the philosophy of Web 2.0. Known as e-learning 2.0, it aims to create a personalized learning environment. E-learning 2.0 combines the use of discrete but complementary tools and web services to support the creation of ad-hoc learning communities. This paper discusses the influenc...

  20. Transfer of L1 Visual Word Recognition Strategies during Early Stages of L2 Learning: Evidence from Hebrew Learners Whose First Language Is Either Semitic or Indo-European

    Science.gov (United States)

    Norman, Tal; Degani, Tamar; Peleg, Orna

    2016-01-01

    The present study examined visual word recognition processes in Hebrew (a Semitic language) among beginning learners whose first language (L1) was either Semitic (Arabic) or Indo-European (e.g. English). To examine if learners, like native Hebrew speakers, exhibit morphological sensitivity to root and word-pattern morphemes, learners made an…

  1. Perceptual Learning Style Matching and L2 Vocabulary Acquisition

    Science.gov (United States)

    Tight, Daniel G.

    2010-01-01

    This study explored learning and retention of concrete nouns in second language Spanish by first language English undergraduates (N = 128). Each completed a learning style (visual, auditory, tactile/kinesthetic, mixed) assessment, took a vocabulary pretest, and then studied 12 words each through three conditions (matching, mismatching, mixed…

  2. The Impact of Morphological Awareness on Iranian Pre-University Students’ Listening Transcription

    Directory of Open Access Journals (Sweden)

    mohammad nabi karimi

    2009-10-01

    Full Text Available Morphological Awareness (henceforth: MA, defined as the ability to understand the morphemic structure of the words, has been reported to affect various aspects of second language performance including reading comprehension ability, spelling performance, etc. Yet, the concept has been far less treated with reference to l2 listening transcription. Thus, against this background, this study aims to investigate the link between MA and listening transcription ability of Iranian pre-university students. To this aim, 40 pre-university students participated in the study, and were assigned to two control and experimental groups. Both groups were first given three short listening passages to transcribe as the pre-tests. The results of the independent-samples t-test revealed no significant difference between the two groups. The experimental group, then, received five one-hour sessions briefing them on the morphological realization of English words. The two groups were then given three short listening passages to transcribe as their post-tests. The results of the independent-samples t-tests attested to the significant difference between the two groups, thus, supporting the relationship between MA and listening transcription ability. The study concludes with some suggestions as to the incorporation of MA into L2 learning programs.

  3. Morphological variation in maize inbred lines

    Directory of Open Access Journals (Sweden)

    Jiban Shrestha

    2014-05-01

    Full Text Available In order to identify morphological variation in maize inbred lines, one hundred five inbred lines were planted under randomized complete block design with two replications at research field of National Maize Research Program, Rampur, Chitwan, Nepal during summer season (March to June, 2010. Descriptive statistics and cluster analysis were done. The results revealed a wide range of morphological variation among the tested inbred lines. The inbred lines grouped in cluster 4 namely PUTU-13, L-9, RL-105, RL-197, RL-103, RML-9, RML-41, RL-165, RL-36, RL-76, RL-125, RL-30-3, L-6, RL-107, RL-174, RL-41, L-13, RML-76 and L-5 had 0.833 days anthesis-silking interval and earlier in flowering (tasseling in 54.50 days and silking in 55.33 days. Moreover they consisted of 1.16 plant aspect, 1.25 ear aspect, 33.08 cm tassel length and 13.5 tassel branch number. Among tested lines, the above inbred lines had better morphological traits, so it was concluded that they were good candidates for development of hybrids and synthetic varieties. DOI: http://dx.doi.org/10.3126/ije.v3i2.10521 International Journal of the Environment Vol.3(2 2014: 98-107

  4. PLATINUM SENSITIVE 2 LIKE impacts growth, root morphology, seed set, and stress responses.

    Directory of Open Access Journals (Sweden)

    Amr R A Kataya

    Full Text Available Eukaryotic protein phosphatase 4 (PP4 is a PP2A-type protein phosphatase that is part of a conserved complex with regulatory factors PSY2 and PP4R2. Various lines of Arabidopsis thaliana with mutated PP4 subunit genes were constructed to study the so far completely unknown functions of PP4 in plants. Mutants with knocked out putative functional homolog of the PSY2 LIKE (PSY2L gene were dwarf and bushy, while plants with knocked out PP4R2 LIKE (PP4R2L looked very similar to WT. The psy2l seedlings had short roots with disorganized morphology and impaired meristem. Seedling growth was sensitive to the genotoxin cisplatin. Global transcript analysis (RNA-seq of seedlings and rosette leaves revealed several groups of genes, shared between both types of tissues, strongly influenced by knocked out PSY2L. Receptor kinases, CRINKLY3 and WAG1, important for growth and development, were down-regulated 3-7 times. EUKARYOTIC ELONGATION FACTOR5A1 was down-regulated 4-6 fold. Analysis of hormone sensitive genes indicated that abscisic acid levels were high, while auxin, cytokinin and gibberellic acid levels were low in psy2l. Expression of specific transcription factors involved in regulation of anthocyanin synthesis were strongly elevated, e.g. the master regulator PAP1, and intriguingly TT8, which is otherwise mainly expressed in seeds. The psy2l mutants accumulated anthocyanins under conditions where WT did not, pointing to PSY2L as a possible upstream negative regulator of PAP1 and TT8. Expression of the sugar-phosphate transporter GPT2, important for cellular sugar and phosphate homeostasis, was enhanced 7-8 times. Several DNA damage response genes, including the cell cycle inhibitor gene WEE1, were up-regulated in psy2l. The activation of DNA repair signaling genes, in combination with phenotypic traits showing aberrant root meristem and sensitivity to the genotoxic cisplatin, substantiate the involvement of Arabidopsis PSY2L in maintenance of genome

  5. The Role of Emergent Bilingualism in the Development of Morphological Awareness in Arabic and Hebrew.

    Science.gov (United States)

    Schwartz, Mila; Taha, Haitham; Assad, Hanan; Khamaisi, Ferdos; Eviatar, Zohar

    2016-08-01

    The purpose of the present study was to investigate the role of dual language development and cross-linguistic influence on morphological awareness in young bilinguals' first language (L1) and second language (L2). We examined whether (a) the bilingual children (L1/L2 Arabic and L1/L2 Hebrew) precede their monolingual Hebrew- or Arabic-speaking peers in L1 and L2 morphological awareness, and (b) 1 Semitic language (Arabic) has cross-linguistic influence on another Semitic language (Hebrew) in morphological awareness. The study sample comprised 93 six-year-old children. The bilinguals had attended bilingual Hebrew-Arabic kindergartens for 1 academic year and were divided into 2 groups: home language Hebrew (L1) and home language Arabic (L1). These groups were compared to age-matched monolingual Hebrew speakers and monolingual Arabic speakers. We used nonwords similar in structure to familiar words in both target languages, representing 6 inflectional morphological categories. L1 Arabic and L1 Hebrew bilinguals performed significantly better than Arabic- and Hebrew-speaking monolinguals in the respective languages. Differences were not found between the bilingual groups. We found evidence of cross-linguistic transfer of morphological awareness from Arabic to Hebrew in 2 categories-bound possessives and dual number-probably because these categories are more salient in Palestinian Spoken Arabic than in Hebrew. We conclude that children with even an initial exposure to L2 reveal acceleration of sensitivity to word structure in both of their languages. We suggest that this is due to the fact that two Semitic languages, Arabic and Hebrew, share a common core of linguistic features, together with favorable contextual factors and instructional factors.

  6. Successful Learners of Irish as an L2: Motivation, Identity and Linguistic Mudes

    Directory of Open Access Journals (Sweden)

    Petit Kevin

    2016-07-01

    Full Text Available This article presents the results of a small-scale research conducted for a master’s thesis on the motivation to learn Irish on the part of university students and members of the Gaelic society An Cumann Gaelach. In the light of questionnaires’ results and interviews, the emphasis is placed on the links between motivation, identity, and potential key moments in learners’ lives. Using an AMTB-type questionnaire (n=45, the author puts to the test Dörnyei’s Motivational Self System theory (2005 in the context of the learning of Irish by looking at the correlation between the motivational intensity of 45 students and six variables (Ideal L2 Self, Ought to Self, Ideal L2 Community, Instrumentality, Parental encouragement, and Role of teachers. The notion of Ideal L2 Self, or the capacity to picture oneself speaking an L2 in the future, clearly appears to be strongly correlated with the respondents’ motivational intensity (r=.75 p<.01, in accordance with Dörnyei’s model. However results concerning extrinsic factors differ from previous research, putting forward distinctive features of the learning of minority languages. The second phase of the research looks at the language learning narratives of three An Cumann Gaelach’s members through the qualitative analysis of three interview transcripts. The results clearly show that time spent in Irish summer colleges are linguistic mudes (Pujolar and Puigdevall 2015, or key-moments, which triggered the interest in the language for the three students interviewed.

  7. Effects of IAA, IBA, NAA, and GA3 on rooting and morphological features of Melissa officinalis L. stem cuttings.

    Science.gov (United States)

    Sevik, Hakan; Guney, Kerim

    2013-01-01

    This study analyzed the potential of producing Melissa officinalis L. using stem cuttings. Four different hormones (IAA, IBA, NAA, and GA3) were applied to the cuttings, with and without buds, in two doses (1000 mg/L and 5000 mg/L), and after 60 days, 10 morphological characteristics of newly generated plants were detected, and a statistical analysis was carried out. The results of the study show that the cuttings with at least one bud must be used in order to produce M. officinalis using stem cuttings. Even though the auxin group hormones (IAA, IBA, and NAA) do not have an apparent effect on rooting percentage, these hormones were detected to affect the morphological characteristics of the newly generated plants, especially root generation. GA3 application has a considerable effect on stem height.

  8. Explicit Grammar Instruction in L2 Learners’Writing Development:Effective or Ineffective?

    Institute of Scientific and Technical Information of China (English)

    田秀峰

    2012-01-01

      It has long been in dispute about whether explicit grammar teaching is more effective in second language learning or implicit grammar teaching is. However, there are more than one factor to take into consideration while discussing which way is better for L2 learners. This short essay aims at depicting three respects concerning grammar teaching, namely learning context, language learners’beliefs and needs, and grammar instruction. When educators and practitioners try to adopt grammar instruction either implicitly or explicitly in L2 learners’writing development, they probably need to consider the above three factors and to find out the best way to produce more effective teaching results among their students

  9. L2 Working Memory Capacity and L2 Reading Skill.

    Science.gov (United States)

    Harrington, Mike; Sawyer, Mark

    1992-01-01

    Examines the sensitivity of second-language (L2) working memory (ability to store and process information simultaneously) to differences in reading skills among advanced L2 learners. Subjects with larger L2 working memory capacities scored higher on measures of L2 reading skills, but no correlation was found between reading and passive short-term…

  10. Bilingual Education and L3 Learning: Metalinguistic Advantage or Not?

    Science.gov (United States)

    Rutgers, Dieuwerke; Evans, Michael

    2017-01-01

    Metalinguistic skills are highlighted in the literature as providing bilinguals with an advantage in additional language (L3) learning. The extent to which this may apply to bilingual education and content-and-language-integrated-learning settings, however, is as yet little understood. This article reports on a study exploring and comparing the…

  11. Effects of Nano-CeO2 with Different Nanocrystal Morphologies on Cytotoxicity in HepG2 Cells

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    Lili Wang

    2015-09-01

    Full Text Available Cerium oxide nanoparticles (nano-CeO2 have been reported to cause damage and apoptosis in human primary hepatocytes. Here, we compared the toxicity of three types of nano-CeO2 with different nanocrystal morphologies (cube-, octahedron-, and rod-like crystals in human hepatocellular carcinoma cells (HepG2. The cells were treated with the nano-CeO2 at various concentrations (6.25, 12.5, 25, 50, 100 μg/mL. The crystal structure, size and morphology of nano-CeO2 were investigated by X-ray diffractometry and transmission electron microscopy. The specific surface area was detected using the Brunauer, Emmet and Teller method. The cellular morphological and internal structure were observed by microscopy; apoptotic alterations were measured using flow cytometry; nuclear DNA, mitochondrial membrane potential (MMP, reactive oxygen species (ROS and glutathione (GSH in HepG2 cells were measured using high content screening technology. The scavenging ability of hydroxyl free radicals and the redox properties of the nano-CeO2 were measured by square-wave voltammetry and temperature-programmed-reduction methods. All three types of nano-CeO2 entered the HepG2 cells, localized in the lysosome and cytoplasm, altered cellular shape, and caused cytotoxicity. The nano-CeO2 with smaller specific surface areas induced more apoptosis, caused an increase in MMP, ROS and GSH, and lowered the cell’s ability to scavenge hydroxyl free radicals and antioxidants. In this work, our data demonstrated that compared with cube-like and octahedron-like nano-CeO2, the rod-like nano-CeO2 has lowest toxicity to HepG2 cells owing to its larger specific surface areas.

  12. Investigations on growth morphology, bulk growth and crystalline perfection of L-threonine, an organic nonlinear optical material

    International Nuclear Information System (INIS)

    Linet, J. Mary; Das, S. Jerome

    2010-01-01

    L-threonine single crystal was successfully grown from aqueous solution. The morphology of the grown crystal was compared with the predicted morphology using Bravais-Friedel-Donnay-Harker law and was found to be in good agreement with the predicted morphology. Good optical quality bulk single crystal of enhanced size has been grown using unidirectional crystal growth method. High-resolution X-ray analysis study resulted in a rocking curve with a full width half maximum of 20 arc sec exhibiting the good crystalline quality of the grown crystal. The optical transmission study shows 90% of transmission in the entire visible region that exhibits the good optical quality of the grown crystal. The mechanical properties were analyzed by Vicker's microhardness method.

  13. L’AUTOBIOGRAFIA LINGUISTICA NELL’INSEGNAMENTO-APPRENDIMENTO DELL’ITALIANO L2/LS

    Directory of Open Access Journals (Sweden)

    Andrea Groppaldi

    2010-09-01

    Full Text Available L'autobiografia linguistica è una attività particolarmente utile nell'insegnamento-apprendimento di una lingua straniera. L'apprendente immigrato è invitato a narrare in prima persona le esperienze linguistico-comunicative nella propria L1, nella L2 /LS che sta apprendendo e/o nella lingua seconda che ha acquisito come lingua di comunicazione e di studio nel suo paese di origine, le relazioni umane ed emotive che accompagnano  o hanno accompagnato queste esperienze, le situazioni che ne hanno favorito o ostacolato l'apprendimento. Con l'autobiografia linguistica l'apprendente straniero costruisce, attraverso la scrittura e quindi attraverso un processo di esplicitazione e di riflessione consapevole,  un ponte tra "là" e "qui", tra paese d'origine e il paese di arrivo, tra la vita "prima" e la vita "dopo" lo strappo della migrazione. Ricompone e dà senso alla propria storia, nelle due lingue, esprime affetti ed emozioni, rinomina il mondo e se ne riappropria ricostruendo insieme la propria identità, esplora se stesso e si fa conoscere ai suoi pari e all'insegnante in un rapporto di condivisione e di comprensione reciproca: si crea un contesto non di integrazione, ma di inclusione. A sua volta il docente può meglio comprendere le strategie di apprendimento dell'apprendente, la sua personalità, le sue difficoltà e progettare strategie didattiche più efficaci, perché più individuali e orientate al successo nella comunicazione e nell'apprendimento.   Linguistic autobiography is especially useful in the teaching and learning of a foreign language. The foreign learner is asked to narrate, in the first person, his/her linguistic-communicative experiences in their L1 and in the L2/FL which they are learning and/or in the second language they have acquired for communication or study in their home country, focusing on the emotional and human relationships which accompanied this experience and the situations which encouraged or blocked the

  14. Morphological, biochemical and sensory characteristics of black mulberry fruits (Morus nigra L.)

    OpenAIRE

    Beáta Stehlíková; Marcela Čuláková; Andrej Sinica; Lucia Kucelová; Ján Brindza

    2013-01-01

    This work aimed at the morphological, biochemical, technological and sensorial determination of black mulberry (Morus nigra L. – MN)  fruitage and their utilization in the food production branches. For the experimental purposes were selected 50 genotypes of this population grown in the Pukanec surroundings. The medium fruitage weight determined in the selected collection ranged from 7.26 g (MN-1) to 1.42 g (MN-14), fruitage length in a range of 13.51 mm (MN-14) to 29.20 mm (MN-12) and the med...

  15. Effect of the microstructural morphology on UO{sub 2} powders

    Energy Technology Data Exchange (ETDEWEB)

    Ziouane, Y.; Lalleman, S.; Leturcq, G. [CEA, Centre de Marcoule, Nuclear Energy Division, RadioChemistry and Processes Department, SERA, LED, F-30207 Bagnols sur Ceze (France); Arab-Chapelet, B. [CEA, Centre de Marcoule, Nuclear Energy Division, RadioChemistry and Processes Department, SERA, LCAR, F-30207 Bagnols sur Ceze (France)

    2016-07-01

    Several UO{sub 2} powders with different morphologies were synthesized and characterized. Three different morphologies were synthesized thanks to sol-gel process (big heap of about 200 μm wide consisting of sintered crystallites) on the one hand, and to oxalic precipitations (one square platelet morphology and one hexagonal stick morphology) on the other hand. Significant differences in dissolution kinetics were observed. Therefore, the morphology of the powders was found to be a key parameter that has to be considered in the studies of UO{sub 2} dissolution kinetics. The second part of the study consists in dissolving in nitric acid in in the same operating conditions three UO{sub 2} powders having different crystallites sizes. It was shown that dissolution kinetics is dependent on the morphology at the micrometer scale but also on the powder oxygen stoichiometry. (authors)

  16. Deep learning based classification of morphological patterns in RCM to guide noninvasive diagnosis of melanocytic lesions (Conference Presentation)

    Science.gov (United States)

    Kose, Kivanc; Bozkurt, Alican; Ariafar, Setareh; Alessi-Fox, Christi A.; Gill, Melissa; Dy, Jennifer G.; Brooks, Dana H.; Rajadhyaksha, Milind

    2017-02-01

    In this study we present a deep learning based classification algorithm for discriminating morphological patterns that appear in RCM mosaics of melanocytic lesions collected at the dermal epidermal junction (DEJ). These patterns are classified into 6 distinct types in the literature: background, meshwork, ring, clod, mixed, and aspecific. Clinicians typically identify these morphological patterns by examination of their textural appearance at 10X magnification. To mimic this process we divided mosaics into smaller regions, which we call tiles, and classify each tile in a deep learning framework. We used previously acquired DEJ mosaics of lesions deemed clinically suspicious, from 20 different patients, which were then labelled according to those 6 types by 2 expert users. We tried three different approaches for classification, all starting with a publicly available convolutional neural network (CNN) trained on natural image, consisting of a series of convolutional layers followed by a series of fully connected layers: (1) We fine-tuned this network using training data from the dataset. (2) Instead, we added an additional fully connected layer before the output layer network and then re-trained only last two layers, (3) We used only the CNN convolutional layers as a feature extractor, encoded the features using a bag of words model, and trained a support vector machine (SVM) classifier. Sensitivity and specificity were generally comparable across the three methods, and in the same ranges as our previous work using SURF features with SVM . Approach (3) was less computationally intensive to train but more sensitive to unbalanced representation of the 6 classes in the training data. However we expect CNN performance to improve as we add more training data because both the features and the classifier are learned jointly from the data. *First two authors share first authorship.

  17. Morphology of the spectral resonance structure of the electromagnetic background noise in the range of 0.1–4 Hz at L = 5.2

    Directory of Open Access Journals (Sweden)

    A. G. Yahnin

    2003-03-01

    Full Text Available Continuous observations of fluctuations of the geomagnetic field at Sodankylä Geophysical Observatory (L = 5.2 were used for a comprehensive morphological study of the spectral resonance structure (SRS seen in the background electromagnetic noise in the frequency range of 0.1–4.0 Hz. It is shown that the occurrence rate of SRS is higher in the nighttime than in the daytime. The occurrence rate is higher in winter than in summer. The SRS frequencies and the difference between neighbouring eigenfrequencies (the frequency scale increase towards nighttime and decrease towards daytime. Both frequency scale and occurrence rate exhibit a clear tendency to decrease from minimum to maximum of the solar activity cycle. It is found that the occurrence rate of SRS decreases when geomagnetic activity increases. The SRS is believed to be a consequence of a resonator for Alfvén waves, which is suggested to exist in the upper ionosphere. According to the theory of the ionospheric Alfvén resonator (IAR, characteristics of SRS crucially depend on electron density in the F-layer maximum, as well as on the altitudinal scale of the density decay above the maximum.We compared the SRS morphological properties with predictions of the IAR theory. The ionospheric parameters needed for calculation were obtained from the ionosphere model (IRI-95, as well as from measurements made with the ionosonde in Sodankylä. We conclude that, indeed, the main morphological properties of SRS are explained on the basis of the IAR theory. The measured parameters of SRS can be used for improving the ionospheric models.Key words. Ionosphere (auroral ionosphere; wave propagation – Radio Science (electromagnetic noise and interference

  18. Is Morphological Awareness a Relevant Predictor of Reading Fluency and Comprehension? New Evidence From Italian Monolingual and Arabic-Italian Bilingual Children

    Directory of Open Access Journals (Sweden)

    Mirta Vernice

    2018-03-01

    Full Text Available In this study, we examined the contribution of morphological awareness to reading competence in a group of Italian L1 and Arabic-Italian early L2 children, i.e., exposed to Italian before 3 years of age. Children from first to fifth grade (age range: 6–11 years old were tested on a range of morphological awareness and lexical tasks. Reading ability was tested through standardized tests of reading fluency and comprehension. Results showed that L1 children outperformed L2 on every measure of morphological awareness, as well as on reading tests. Regression analyses revealed that morphological awareness contributed to a different extent to reading ability across groups. Accuracy in the morphological awareness tasks was a significant predictor of word (and non-word reading fluency in L1 and L2 first and second graders, while only in L1 third to fifth graders, response times and accuracy to a morphological awareness task explained a unique amount of variance in reading comprehension. Our results highlight the critical role of morphological processing in reading efficiency and suggest that a training inspired by morphological awareness may improve reading skills also in bilingual students.

  19. On the Relationship between Brain Laterality and Language Proficiency in L2: A Replication Study

    Directory of Open Access Journals (Sweden)

    Nima Shakouri

    2016-06-01

    Full Text Available The present paper attempted to investigate whether there is any significant relationship between participants' brain laterality and L2 proficiency level. To carry out the experiment, 30 participants administered in the present study. Fifteen of them did not have any English language learning experience and were at the start of language learning, while the rest had attended L2 learning classes for about 2 years in a popular English language center, located in Bandar-e Anzali, Iran. Finally, the researchers concluded that the activity of the right hemisphere went up by the increase in language proficiency among bilinguals. Thereupon, the result of the paper was at variance with Albert and Obler's (1978 early work on hemispheric differentiation, which indicated that bilinguals were less hemispheric dominant than monolinguals.

  20. L2 Spelling Errors in Italian Children with Dyslexia.

    Science.gov (United States)

    Palladino, Paola; Cismondo, Dhebora; Ferrari, Marcella; Ballagamba, Isabella; Cornoldi, Cesare

    2016-05-01

    The present study aimed to investigate L2 spelling skills in Italian children by administering an English word dictation task to 13 children with dyslexia (CD), 13 control children (comparable in age, gender, schooling and IQ) and a group of 10 children with an English learning difficulty, but no L1 learning disorder. Patterns of difficulties were examined for accuracy and type of errors, in spelling dictated short and long words (i.e. disyllables and three syllables). Notably, CD were poor in spelling English words. Furthermore, their errors were mainly related with phonological representation of words, as they made more 'phonologically' implausible errors than controls. In addition, CD errors were more frequent for short than long words. Conversely, the three groups did not differ in the number of plausible ('non-phonological') errors, that is, words that were incorrectly written, but whose reading could correspond to the dictated word via either Italian or English rules. Error analysis also showed syllable position differences in the spelling patterns of CD, children with and English learning difficulty and control children. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Learners’ Perceptions of the Effectiveness of Spaced Learning Schedule in L2 Vocabulary Learning

    Directory of Open Access Journals (Sweden)

    Amir Reza Lotfolahi

    2016-05-01

    Full Text Available The spacing effect is a ubiquitous phenomenon, whereby memory is enhanced for the information that is learned across different points in time rather than being learned at once. A considerable amount of research has focused on the nature of the spacing effect, and there is general acceptance that spacing learning events out in time promotes learning. However, fewer studies have been conducted in educational settings. The aim of this study is to explore learners’ perceptions of different spacing schedules (massed vs. spaced. To achieve the purpose of the study, we taught 30 children 24 English–Farsi word pairs utilizing different spacing schedules. Later, we administered a questionnaire to explore leaarners’ perceptions of both massed and spaced schedules. The results revealed that the children percieved spaced practice to be more effective than massed practice.

  2. Global and nonglobal parameters of horizontal-branch morphology of globular clusters

    International Nuclear Information System (INIS)

    Milone, A. P.; Marino, A. F.; Dotter, A.; Norris, J. E.; Jerjen, H.; Asplund, M.

    2014-01-01

    The horizontal-branch (HB) morphology of globular clusters (GCs) is mainly determined by metallicity. However, the fact that GCs with almost the same metallicity exhibit different HB morphologies demonstrates that at least one more parameter is needed to explain the HB morphology. It has been suggested that one of these should be a global parameter that varies from GC to GC and the other a nonglobal parameter that varies within the GC. In this study we provide empirical evidence corroborating this idea. We used the photometric catalogs obtained with the Advanced Camera for Surveys of the Hubble Space Telescope and analyze the color-magnitude diagrams of 74 GCs. The HB morphology of our sample of GCs has been investigated on the basis of the two new parameters L1 and L2 that measure the distance between the red giant branch and the coolest part of the HB and the color extension of the HB, respectively. We find that L1 correlates with both metallicity and age, whereas L2 most strongly correlates with the mass of the hosting GC. The range of helium abundance among the stars in a GC, characterized by ΔY and associated with the presence of multiple stellar populations, has been estimated in a few GCs to date. In these GCs we find a close relationship among ΔY, GC mass, and L2. We conclude that age and metallicity are the main global parameters, while the range of helium abundance within a GC is the main nonglobal parameter defining the HB morphology of Galactic GCs.

  3. DAT1 polymorphism determines L-DOPA effects on learning about others' prosociality.

    Directory of Open Access Journals (Sweden)

    Christoph Eisenegger

    Full Text Available Despite that a wealth of evidence links striatal dopamine to individualś reward learning performance in non-social environments, the neurochemical underpinnings of such learning during social interaction are unknown. Here, we show that the administration of 300 mg of the dopamine precursor L-DOPA to 200 healthy male subjects influences learning about a partners' prosocial preferences in a novel social interaction task, which is akin to a repeated trust game. We found learning to be modulated by a well-established genetic marker of striatal dopamine levels, the 40-bp variable number tandem repeats polymorphism of the dopamine transporter (DAT1 polymorphism. In particular, we found that L-DOPA improves learning in 10/10R genoype subjects, who are assumed to have lower endogenous striatal dopamine levels and impairs learning in 9/10R genotype subjects, who are assumed to have higher endogenous dopamine levels. These findings provide first evidence for a critical role of dopamine in learning whether an interaction partner has a prosocial or a selfish personality. The applied pharmacogenetic approach may open doors to new ways of studying psychiatric disorders such as psychosis, which is characterized by distorted perceptions of others' prosocial attitudes.

  4. Machine-Learning Algorithms to Automate Morphological and Functional Assessments in 2D Echocardiography.

    Science.gov (United States)

    Narula, Sukrit; Shameer, Khader; Salem Omar, Alaa Mabrouk; Dudley, Joel T; Sengupta, Partho P

    2016-11-29

    Machine-learning models may aid cardiac phenotypic recognition by using features of cardiac tissue deformation. This study investigated the diagnostic value of a machine-learning framework that incorporates speckle-tracking echocardiographic data for automated discrimination of hypertrophic cardiomyopathy (HCM) from physiological hypertrophy seen in athletes (ATH). Expert-annotated speckle-tracking echocardiographic datasets obtained from 77 ATH and 62 HCM patients were used for developing an automated system. An ensemble machine-learning model with 3 different machine-learning algorithms (support vector machines, random forests, and artificial neural networks) was developed and a majority voting method was used for conclusive predictions with further K-fold cross-validation. Feature selection using an information gain (IG) algorithm revealed that volume was the best predictor for differentiating between HCM ands. ATH (IG = 0.24) followed by mid-left ventricular segmental (IG = 0.134) and average longitudinal strain (IG = 0.131). The ensemble machine-learning model showed increased sensitivity and specificity compared with early-to-late diastolic transmitral velocity ratio (p 13 mm. In this subgroup analysis, the automated model continued to show equal sensitivity, but increased specificity relative to early-to-late diastolic transmitral velocity ratio, e', and strain. Our results suggested that machine-learning algorithms can assist in the discrimination of physiological versus pathological patterns of hypertrophic remodeling. This effort represents a step toward the development of a real-time, machine-learning-based system for automated interpretation of echocardiographic images, which may help novice readers with limited experience. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  5. Comparing L2 Word Learning through a Tablet or Real Objects: What Benefits Learning Most?

    NARCIS (Netherlands)

    Vlaar, M.A.J.; Verhagen, J.; Oudgenoeg-Paz, O.; Leseman, P.P.M.

    2017-01-01

    In child-robot interactions focused on language learning, tablets are often used to structure the interaction between the robot and the child. However, it is not clear how tablets affect children’s learning gains. Real-life objects are thought to benefit children’s word learning, but it is not clear

  6. Joint International Workshop on Professional Learning, Competence Development and Knowledge Management - LOKMOL and L3NCD

    NARCIS (Netherlands)

    Memmel, Martin; Ras, Eric; Weibelzahl, Stephan; Burgos, Daniel; Olmedilla, Daniel; Wolpers, Martin

    2006-01-01

    Memmel, M., Ras, E., Weibelzahl, S., Burgos, D., Olmedilla, D., & Wolpers, M. (2006). Joint International Workshop on Professional Learning, Competence Development and Knowledge Management - LOKMOL and L3NCD. Proceedings of ECTEL 2006. October 2nd-4th, Crete, Greece. Retrieved October 2nd, 2006,

  7. Morphological Diversity of Fruits, Seeds and Seedlings of Pongamia (Pongamia pinnata (L. Pierre in Java Island

    Directory of Open Access Journals (Sweden)

    NFN Supriyanto

    2017-12-01

    Full Text Available Pongamia (Pongamia pinnata (L. Pierre is one of a potential tree species to produce biodiesel. Pongamia-based biodiesel development program is still constrained by the availability of quality and quantity seeds due to the limited of seed sources. The purpose of this research was to identify the morphological diversity of fruits, seeds and seedlings from 5 populations in Java Island. Randomized completely design and randomized block design were used to assess the difference of fruits, seeds and seedlings morphological characteristics among populations. Principal component and hierarchy cluster analysis were used to explain variation pattern among populations. The results showed that the difference of populations was significantly affected by the difference of fruits, seeds, and seedlings morphology of pongamia. Seeds from Carita population showed good quality seed indicators with moisture content of 19.31%, and germination capacity of 74.50%. Sturdiness quotient of the seedling was 10.78. Contribution of genetic factor was higher than environtment factor is relation to the differences of morphological characteristics of fruits, seeds and seedlings of pongamia. Morphological character of the five populations can be divided into 3 groups, i.e. the first group of Batukaras and Kebumen, second group of Alas Purwo and Baluran, and group 3 was Carita.

  8. Leaf morphology and phenology of Beech (Fagus sylvatica L.) are linked to environmental conditions depending on the altitudinal origin

    Science.gov (United States)

    Capdevielle-Vargas, Renee; Schuster, Christina; Estrella, Nicole; Menzel, Annette

    2014-05-01

    One of the principal responses of temperate climate trees to climate warming, besides migration, will be in-situ adaptation/evolution. For both, germination and growth rates can have a strong impact on survival and long-term recruitment and establishment of a species. Leaf morphology traits, together with phenology, are relevant to the study of inherent capacities of plants to adapt to an ever changing climate, especially in alpine regions, where a rapid warming has been observed in the last decades. The aim of this study was to evaluate the changes in possible adaptive traits (e.g. leaf morphology and phenology) of Beech (Fagus sylvatica L.) and to asses a decisive component of the survival strategy of this important broadly distributed Central European tree species. We collected beech seeds at six sites along two transects of a south- (900, 1000 and 1100-1400 m.a.s.l.) and a north-facing slope (800, 900 and 1100 m.a.s.l.) in 2011 (mast year) near Garmisch-Partenkirchen, Germany. All the seeds were stratified before sowing; 150 seeds were selected from each site and sowed (at the beginning of the spring) in square containers in a greenhouse under the same climatic conditions; seven phenological stages were defined following a modified beech germination key and the phenology of every seed was recorded three times a week. Harvesting took place 38/42 days after sowing and the specific leaf area (SLA), biomass, and leaf morphology (lamina length and width) were recorded for each seedling. Seeds from lower sites of the two transects presented a poorer germination rates (e.g. 30% for the south 900 m.a.s.l. site) and (75% for the north 800 m.a.s.l. site) when compared to seeds originating from higher elevations within the same transect. The highest germination percentages (98 and 85%) were observed in seeds originating from the highest elevations (e.g. 1100-1400 m.a.s.l. of the south site and 1100 m.a.s.l. of the north site, respectively). Although no significant

  9. Cancer survival analysis using semi-supervised learning method based on Cox and AFT models with L1/2 regularization.

    Science.gov (United States)

    Liang, Yong; Chai, Hua; Liu, Xiao-Ying; Xu, Zong-Ben; Zhang, Hai; Leung, Kwong-Sak

    2016-03-01

    One of the most important objectives of the clinical cancer research is to diagnose cancer more accurately based on the patients' gene expression profiles. Both Cox proportional hazards model (Cox) and accelerated failure time model (AFT) have been widely adopted to the high risk and low risk classification or survival time prediction for the patients' clinical treatment. Nevertheless, two main dilemmas limit the accuracy of these prediction methods. One is that the small sample size and censored data remain a bottleneck for training robust and accurate Cox classification model. In addition to that, similar phenotype tumours and prognoses are actually completely different diseases at the genotype and molecular level. Thus, the utility of the AFT model for the survival time prediction is limited when such biological differences of the diseases have not been previously identified. To try to overcome these two main dilemmas, we proposed a novel semi-supervised learning method based on the Cox and AFT models to accurately predict the treatment risk and the survival time of the patients. Moreover, we adopted the efficient L1/2 regularization approach in the semi-supervised learning method to select the relevant genes, which are significantly associated with the disease. The results of the simulation experiments show that the semi-supervised learning model can significant improve the predictive performance of Cox and AFT models in survival analysis. The proposed procedures have been successfully applied to four real microarray gene expression and artificial evaluation datasets. The advantages of our proposed semi-supervised learning method include: 1) significantly increase the available training samples from censored data; 2) high capability for identifying the survival risk classes of patient in Cox model; 3) high predictive accuracy for patients' survival time in AFT model; 4) strong capability of the relevant biomarker selection. Consequently, our proposed semi

  10. The Beneficial Role of L1 Spoken Language Skills on Initial L2 Sign Language Learning: Cognitive and Linguistic Predictors of M2L2 Acquisition

    Science.gov (United States)

    Williams, Joshua T.; Darcy, Isabelle; Newman, Sharlene D.

    2017-01-01

    Understanding how language modality (i.e., signed vs. spoken) affects second language outcomes in hearing adults is important both theoretically and pedagogically, as it can determine the specificity of second language (L2) theory and inform how best to teach a language that uses a new modality. The present study investigated which…

  11. Vibrational spectroscopic and theoretical study of 3,5-dimethyl-1-thiocarboxamide pyrazole (L) and the complexes Co2L2Cl4, Cu2L2Cl4 and Cu2L2Br2

    International Nuclear Information System (INIS)

    Nemcsok, Denes; Kovacs, Attila; Szecsenyi, Katalin Meszaros; Leovac, Vukadin M.

    2006-01-01

    In the present paper we report a joint experimental and theoretical study of 3,5-dimethyl-1-thiocarboxamide pyrazole (L) and its complexes Co 2 L 2 Cl 4 , Cu 2 L 2 Cl 4 and Cu 2 L 2 Br 2 . DFT computations were used to model the structural and bonding properties of the title compounds as well as to derive a reliable force field for the normal coordinate analysis of L. The computations indicated the importance of hydrogen bonding interactions in stabilising the global minimum structures on the potential energy surfaces. In contrast to the S-bridged binuclear Cu 2 L 2 Br 2 complex found in the crystal, our computations predicted the formation of (CuLBr) 2 dimers in the isolated state stabilized by very strong (53 kJ/mol) N-H...Br hydrogen bonding interactions. On the basis of FT-IR and FT-Raman experiments and the DFT-derived scaled quantum mechanical force field we carried out a complete normal coordinate analysis of L. The FT-IR spectra of the three complexes were interpreted using the present assignment of L, literature data and computed results

  12. Interplay of Languaging and Gameplay: Player-Game Interactions as Ecologies for Languaging and Situated L2 Development

    Science.gov (United States)

    Ibrahim, Karim Hesham Shaker

    2016-01-01

    The field of game-mediated L2 learning has grown exponentially, and much has been discovered about the potentials of game-mediated interactions for L2 development, yet the fine-grained dynamics of player-game interactions and how they come to facilitate and afford L2 development are still largely underexplored. To address this gap in the…

  13. The Role of L-type Calcium Channels in Olfactory Learning and Its Modulation by Norepinephrine

    Directory of Open Access Journals (Sweden)

    Abhinaba Ghosh

    2017-12-01

    Full Text Available L type calcium channels (LTCCs are prevalent in different systems and hold immense importance for maintaining/performing selective functions. In the nervous system, CaV1.2 and CaV1.3 are emerging as critical modulators of neuronal functions. Although the general role of these calcium channels in modulating synaptic plasticity and memory has been explored, their role in olfactory learning is not well understood. In this review article we first discuss the role of LTCCs in olfactory learning especially focusing on early odor preference learning in neonate rodents, presenting evidence that while NMDARs initiate stimulus-specific learning, LTCCs promote protein-synthesis dependent long-term memory (LTM. Norepinephrine (NE release from the locus coeruleus (LC is essential for early olfactory learning, thus noradrenergic modulation of LTCC function and its implication in olfactory learning is discussed here. We then address the differential roles of LTCCs in adult learning and learning in aged animals.

  14. Matching Vocabulary Learning Process with Learning Outcome in L2 Academic Writing: An Exploratory Case Study

    Science.gov (United States)

    Ma, Qing

    2013-01-01

    This exploratory case study of two undergraduates links vocabulary learning approaches with lexical quality measured in academic writing. Employing an array of qualitative data, it is shown that in a "semi-language-rich" learning context, Chinese learners may dispense with rote learning and engage in a more natural learning approach in which…

  15. Integrating human and machine intelligence in galaxy morphology classification tasks

    Science.gov (United States)

    Beck, Melanie R.; Scarlata, Claudia; Fortson, Lucy F.; Lintott, Chris J.; Simmons, B. D.; Galloway, Melanie A.; Willett, Kyle W.; Dickinson, Hugh; Masters, Karen L.; Marshall, Philip J.; Wright, Darryl

    2018-06-01

    Quantifying galaxy morphology is a challenging yet scientifically rewarding task. As the scale of data continues to increase with upcoming surveys, traditional classification methods will struggle to handle the load. We present a solution through an integration of visual and automated classifications, preserving the best features of both human and machine. We demonstrate the effectiveness of such a system through a re-analysis of visual galaxy morphology classifications collected during the Galaxy Zoo 2 (GZ2) project. We reprocess the top-level question of the GZ2 decision tree with a Bayesian classification aggregation algorithm dubbed SWAP, originally developed for the Space Warps gravitational lens project. Through a simple binary classification scheme, we increase the classification rate nearly 5-fold classifying 226 124 galaxies in 92 d of GZ2 project time while reproducing labels derived from GZ2 classification data with 95.7 per cent accuracy. We next combine this with a Random Forest machine learning algorithm that learns on a suite of non-parametric morphology indicators widely used for automated morphologies. We develop a decision engine that delegates tasks between human and machine and demonstrate that the combined system provides at least a factor of 8 increase in the classification rate, classifying 210 803 galaxies in just 32 d of GZ2 project time with 93.1 per cent accuracy. As the Random Forest algorithm requires a minimal amount of computational cost, this result has important implications for galaxy morphology identification tasks in the era of Euclid and other large-scale surveys.

  16. Development and implementation of a novel assay for L-2-hydroxyglutarate dehydrogenase (L-2-HGDH) in cell lysates: L-2-HGDH deficiency in 15 patients with L-2-hydroxyglutaric aciduria

    DEFF Research Database (Denmark)

    Kranendijk, M; Salomons, G S; Gibson, K M

    2009-01-01

    L-2-hydroxyglutaric aciduria (L-2-HGA) is a rare inherited autosomal recessive neurometabolic disorder caused by mutations in the gene encoding L-2-hydroxyglutarate dehydrogenase. An assay to evaluate L-2-hydroxyglutarate dehydrogenase (L-2-HGDH) activity in fibroblast, lymphoblast and/or lymphoc...

  17. Active Learning: Qualitative Inquiries into Vocabulary Instruction in Chinese L2 Classrooms

    Science.gov (United States)

    Shen, Helen H.; Xu, Wenjing

    2015-01-01

    Active learning emerged as a new approach to learning in the 1980s. The core concept of active learning involves engaging students not only in actively exploring knowledge but also in reflecting on their own learning process in order to become more effective learners. Because the nonalphabetic nature of the Chinese writing system makes learning to…

  18. How new words (don't) become memories : Lexicalization in advanced L1 Dutch learners of L2 English

    NARCIS (Netherlands)

    Keijzer, Merel

    It is an undisputed fact that learning – and remembering – new words is key in successful second language acquisition. And yet researching how vocabulary acquisition takes place is one of the most difficult endeavors in second language acquisition. We can test how many L2 words a learner knows, but

  19. Changes in growth, rRNA content, and cell morphology of Listeria monocytogenes induced by CO2 up- and downshift

    DEFF Research Database (Denmark)

    Jydegaard-Axelsen, A.M.; Aaes-Jorgensen, A.; Koch, A.G.

    2005-01-01

    Cell morphology, rRNA content, and growth were examined for Listeria monocytogenes LO28 and EGD, respectively, grown in brain-heart infusion (BHI) and on slices of sausage at 10degreesC in 100% CO2, 100% N-2, and air. In CO2, filamentous cells were formed by both strains on sausage slices and by L...... units under circumstances where filamentation may occur. Furthermore, the study illustrates the lack of residual inhibitory effect of CO2 in this type of products after opening....... in air and CO2.. Septation and cell division were induced in the filaments after a CO2 downshift (i.e., exposure to air). In BHI, the number of colony forming units increased rapidly when L. monocytogenes EGD grown in CO2 was exposed to air whereas the number of L. monocytogenes LO28 remained almost...

  20. Analysis of LOFT loss-of-coolant experiments L2-2, L2-3, and L3-0

    International Nuclear Information System (INIS)

    Leach, L.P.; Linebarger, J.H.

    1979-01-01

    A summary of results from Loss-of-Coolant Experiments (LOCE) L2-2, L2-3, and L3-0, conducted in the Loss-of-Fluid Test (LOFT) facility, and conclusions from posttest analyses of the experimental data are presented. LOCEs L2-2 and L2-3 were nuclear large break experiments and were dominated by a core-wide fuel rod cladding rewet, which limited the maximum fuel temperature. Analytical models only conservatively predicted the measured fuel rod temperatures and will require improvements to provide best estimate predictions in this area. Analysis of a large commercial pressurized water reactor (PWR) indicates that the cladding rewet observed in LOFT is also likely to occur in a large PWR, and that, therefore, safety analysis calculations of large loss-of-coolant accidents (LOCA) are more conservative than previously thought. LOCE L3-0 was an isothermal small break (top of pressurizer) experiment and illustrated that the pressurizer fills after the primary system fluid saturates someplace other than the pressurizer itself, that the indicated pressurizer level is higher than the actual level, and that additional model development and assessment work is necessary in order to predict small LOCAs as accurately as large LOCAs

  1. A morphological perceptron with gradient-based learning for Brazilian stock market forecasting.

    Science.gov (United States)

    Araújo, Ricardo de A

    2012-04-01

    Several linear and non-linear techniques have been proposed to solve the stock market forecasting problem. However, a limitation arises from all these techniques and is known as the random walk dilemma (RWD). In this scenario, forecasts generated by arbitrary models have a characteristic one step ahead delay with respect to the time series values, so that, there is a time phase distortion in stock market phenomena reconstruction. In this paper, we propose a suitable model inspired by concepts in mathematical morphology (MM) and lattice theory (LT). This model is generically called the increasing morphological perceptron (IMP). Also, we present a gradient steepest descent method to design the proposed IMP based on ideas from the back-propagation (BP) algorithm and using a systematic approach to overcome the problem of non-differentiability of morphological operations. Into the learning process we have included a procedure to overcome the RWD, which is an automatic correction step that is geared toward eliminating time phase distortions that occur in stock market phenomena. Furthermore, an experimental analysis is conducted with the IMP using four complex non-linear problems of time series forecasting from the Brazilian stock market. Additionally, two natural phenomena time series are used to assess forecasting performance of the proposed IMP with other non financial time series. At the end, the obtained results are discussed and compared to results found using models recently proposed in the literature. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Sex Differences in L2 Vocabulary Learning Strategies.

    Science.gov (United States)

    Catalan, Rosa Maria Jimenez

    2003-01-01

    Reports the results of a descriptive study on sex differences in the use of a second language. A questionnaire was administered to 581 Spanish-speaking students learning Basque and English as second language to answer the following question: Do male and female second language learners differ in the number and the range of vocabulary strategies…

  3. Crystal structure of l-leucyl-l-isoleucine 2,2,2-trifluoroethanol monosolvate

    Directory of Open Access Journals (Sweden)

    Carl Henrik Görbitz

    2016-05-01

    Full Text Available Hydrophobic dipeptides with either l-Leu or l-Phe constitute a rather heterogeneous group of crystal structures. Some form materials with large water-filled channels, but there is also a pronounced tendency to incorporate organic solvent molecules, which then act as acceptors for one of the three H atoms of the charged N-terminal amino group. l-Leu-l-Ile has uniquely been obtained as two distinct hydrates, but has so far failed to co-crystallize with a simple alcohol. The present structure of C12H24N2O3·CF3CH2OH, which crystallizes with two dipeptide and two solvent molecules in the asymmetric unit, demonstrates that when 2,2,2-trifluoroethanol is used as a solvent, its high capacity as a hydrogen-bond donor leads to formation of an alcohol solvate.

  4. Roles of Position, Stress, and Proficiency in L2 Children's Spelling: A Developmental Perspective

    Science.gov (United States)

    Hong, Su Chin; Chen, Shu Hui

    2011-01-01

    This study investigated the roles of phoneme position, stress, and proficiency in L2 spelling development by Taiwanese students learning English as a Foreign Language (EFL), an alphabetic writing system typologically different from the learners' L1 logographic system. Structured nonword spelling tests were administered to EFL sixth-graders with…

  5. College Students' Possible L2 Self Development in an EFL Context during the Transition Year

    Science.gov (United States)

    Zhan, Ying; Wan, Zhi Hong

    2016-01-01

    In the field of second language learning motivation, the studies on process-oriented nature of possible L2 selves are scarce. In order to address this research gap, this study explored how a group of five Chinese non-English-major undergraduates developed their possible L2 selves during the transition year from high school to university. The…

  6. Analysis of morphology, DNA and isozyme of leaf mutation in Brassica napus L

    International Nuclear Information System (INIS)

    Luo Zhen; Hu Dongwei; Li Xiaobai

    2008-01-01

    This paper aims to study the rule of irradiating effects, provide the effective way of analyzing mutant, and discuss the production application of mutant. By irradiating the 040B of Brassica napus L with . 0Co γ- ray, an obvious leaf mutation (ML) with large leaf area was found. The ML which has been inherited stably after three generations was compared with wide-type (CK) on the morphologic, DNA and isozymic levels. Results showed that S 4 and S17 from RAPD were two molecular markers which can express good polymorphism and have close relationships with leaf mutation sites. And in the analysis of EST and POD between ML and CK, the polymorphisms also proved that many discrepancies exist between ML and CK on the protein level. In addition, the research results in question can be applied to the breeding and genetic research of Brassica napus L

  7. From eLearning to Digital Transformation: A Framework and Implications for L&D

    OpenAIRE

    Seufert, Sabine; Meier, Christoph

    2016-01-01

    How can the learning function (L&D) support learning and innovation ability of the entire organization in times of digital transformation? The core challenges for the learning function are twofold. Competence clarification: What are relevant “digital competences” in terms of knowledge, skills and attitudes that employees need in order to cope with digital transformation? Competence development: How to organize, design and support learning processes contributing to digital competences and digi...

  8. Assessing Input Enhancement as Positive Factor and Its Impact on L2 Vocabulary Learning

    Science.gov (United States)

    Motlagh, Seyyed Fariborz Pishdadi; Nasab, Mahdiyeh Seyed Beheshti

    2015-01-01

    Input enhancement's role to promote learners' awareness in L2 contexts has caused a tremendous amount of research. Conspicuously, by regarding all aspects of input enhancement, the study aimed to find out how differently many kinds of input enhancement factors such as bolding, underlining, and capitalizing impact on L2 learners' vocabulary…

  9. Modulation ofTcf7l2 expression alters behavior in mice.

    Directory of Open Access Journals (Sweden)

    Daniel Savic

    Full Text Available The comorbidity of type 2 diabetes (T2D with several psychiatric diseases is well established. While environmental factors may partially account for these co-occurrences, common genetic susceptibilities could also be implicated in the confluence of these diseases. In support of shared genetic burdens, TCF7L2, the strongest genetic determinant for T2D risk in the human population, has been recently implicated in schizophrenia (SCZ risk, suggesting that this may be one of many loci that pleiotropically influence both diseases. To investigate whether Tcf7l2 is involved in behavioral phenotypes in addition to its roles in glucose metabolism, we conducted several behavioral tests in mice with null alleles of Tcf7l2 or overexpressing Tcf7l2. We identified a role for Tcf7l2 in anxiety-like behavior and a dose-dependent effect of Tcf7l2 alleles on fear learning. None of the mutant mice showed differences in prepulse inhibition (PPI, which is a well-established endophenotype for SCZ. These results show that Tcf7l2 alters behavior in mice. Importantly, these differences are observed prior to the onset of detectable glucose metabolism abnormalities. Whether these differences are related to human anxiety-disorders or schizophrenia remains to be determined. These animal models have the potential to elucidate the molecular basis of psychiatric comorbidities in diabetes and should therefore be studied further.

  10. Bactobolin resistance is conferred by mutations in the L2 ribosomal protein.

    Science.gov (United States)

    Chandler, Josephine R; Truong, Thao T; Silva, Patricia M; Seyedsayamdost, Mohammad R; Carr, Gavin; Radey, Matthew; Jacobs, Michael A; Sims, Elizabeth H; Clardy, Jon; Greenberg, E Peter

    2012-12-18

    Burkholderia thailandensis produces a family of polyketide-peptide molecules called bactobolins, some of which are potent antibiotics. We found that growth of B. thailandensis at 30°C versus that at 37°C resulted in increased production of bactobolins. We purified the three most abundant bactobolins and determined their activities against a battery of bacteria and mouse fibroblasts. Two of the three compounds showed strong activities against both bacteria and fibroblasts. The third analog was much less potent in both assays. These results suggested that the target of bactobolins might be conserved across bacteria and mammalian cells. To learn about the mechanism of bactobolin activity, we isolated four spontaneous bactobolin-resistant Bacillus subtilis mutants. We used genomic sequencing technology to show that each of the four resistant variants had mutations in rplB, which codes for the 50S ribosome-associated L2 protein. Ectopic expression of a mutant rplB gene in wild-type B. subtilis conferred bactobolin resistance. Finally, the L2 mutations did not confer resistance to other antibiotics known to interfere with ribosome function. Our data indicate that bactobolins target the L2 protein or a nearby site and that this is not the target of other antibiotics. We presume that the mammalian target of bactobolins involves the eukaryotic homolog of L2 (L8e). Currently available antibiotics target surprisingly few cellular functions, and there is a need to identify novel antibiotic targets. We have been interested in the Burkholderia thailandensis bactobolins, and we sought to learn about the target of bactobolin activity by mapping spontaneous resistance mutations in the bactobolin-sensitive Bacillus subtilis. Our results indicate that the bactobolin target is the 50S ribosome-associated L2 protein or a region of the ribosome affected by L2. Bactobolin-resistant mutants are not resistant to other known ribosome inhibitors. Our evidence indicates that bactobolins

  11. Effect of milling on morphology of molten salt synthesized Sr3Ti2O7 crystals

    Directory of Open Access Journals (Sweden)

    Kijamnajsuk, S.

    2007-07-01

    Full Text Available Effect of milling liquid (acetone and ethanol, and milling times on morphology of Sr3Ti2O7 (ST7 crystals grow in molten potassium chloride salt at 1250oC for 4 h was investigated. Two kinds of crystals with different morphologies were found: ST7 crystals having a tabular shape of less than 20 μm diameter and small secondary-phase crystals having high symmetry. Milling starting materials in ethanol yielded ST7 crystals that were up to 3 times thinner than those milled with acetone, increasing the (00l Lotgering factor almost twice that when prepared with acetone. Large crystals become a bit smaller and the number of small crystals increased when the milling time increased.

  12. An automatic taxonomy of galaxy morphology using unsupervised machine learning

    Science.gov (United States)

    Hocking, Alex; Geach, James E.; Sun, Yi; Davey, Neil

    2018-01-01

    We present an unsupervised machine learning technique that automatically segments and labels galaxies in astronomical imaging surveys using only pixel data. Distinct from previous unsupervised machine learning approaches used in astronomy we use no pre-selection or pre-filtering of target galaxy type to identify galaxies that are similar. We demonstrate the technique on the Hubble Space Telescope (HST) Frontier Fields. By training the algorithm using galaxies from one field (Abell 2744) and applying the result to another (MACS 0416.1-2403), we show how the algorithm can cleanly separate early and late type galaxies without any form of pre-directed training for what an 'early' or 'late' type galaxy is. We then apply the technique to the HST Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) fields, creating a catalogue of approximately 60 000 classifications. We show how the automatic classification groups galaxies of similar morphological (and photometric) type and make the classifications public via a catalogue, a visual catalogue and galaxy similarity search. We compare the CANDELS machine-based classifications to human-classifications from the Galaxy Zoo: CANDELS project. Although there is not a direct mapping between Galaxy Zoo and our hierarchical labelling, we demonstrate a good level of concordance between human and machine classifications. Finally, we show how the technique can be used to identify rarer objects and present lensed galaxy candidates from the CANDELS imaging.

  13. Cooperative Learning i læreruddannelsen

    DEFF Research Database (Denmark)

    Heiberg, Tobias; Palmvang, Kirsten

    På Læreruddannelsen Blaagaard/KDAS blev der i undervisningsåret 2009/2010 fokuseret på udviklingsarbejde under overskrifterne ’Uddannelsesudviklere’ og ’Varierede undervisningsformer’. Projektet ’Cooperative Learning i læreruddannelsen’ er stablet på benene inden for temaet ’Varierede...... undervisningsformer’ og har til hensigt at undersøge, eksperimentere og indsamle erfaringer med undervisningsmetoderne fra ’Cooperative Learning’ sådan som de fremgår af bogen af samme navn (Kagan & Stenlev, 2006). I denne sammenhæng bygger anvendelsen af CL således specifikt på Spencer Kagans strukturelle tilgang...

  14. Morphology Independent Learning in Modular Robots

    DEFF Research Database (Denmark)

    Christensen, David Johan; Bordignon, Mirko; Schultz, Ulrik Pagh

    2009-01-01

    speed its modules independently and in parallel adjust their behavior based on a single global reward signal. In simulation, we study the learning strategy’s performance on different robot configurations. On the physical platform, we perform learning experiments with ATRON robots learning to move as fast...

  15. Morphology Independent Learning in Modular Robots

    DEFF Research Database (Denmark)

    Christensen, David Johan; Bordignon, Mirko; Schultz, Ulrik Pagh

    2009-01-01

    speed its modules independently and in parallel adjust their behavior based on a single global reward signal. In simulation, we study the learning strategy?s performance on different robot con?gurations. On the physical platform, we perform learning experiments with ATRON robots learning to move as fast...

  16. Effects of Multimedia Instruction on L2 Acquisition of High-Level, Low-Frequency English Vocabulary Words

    Science.gov (United States)

    Cho, Euna

    2017-01-01

    The present study examined the effects of multimedia enhancement in video form in addition to textual information on L2 vocabulary instruction for high-level, low-frequency English words among Korean learners of English. Although input-based incidental learning of L2 vocabulary through extensive reading has been conventionally believed to be…

  17. Morphological stability of Sm123 superconductor during peritectic solidification from Sm211 + L mixture

    International Nuclear Information System (INIS)

    Sumida, Masaki; Shiohara, Yuh; Umeda, Takateru

    2000-01-01

    The interface stability of the Sm 123 superconductor was analyzed in accordance with the constitutional undercooling criterion. As the single-crystal growth of the 123 phase is largely dependent on the growth-interface stability, a quantitative analysis was very much required. From this analysis, it was clarified that the constitutional undercooling must exist in the liquid when the 123 growth interface comes close to a 211 particle during the peritectic solidification. It was also predicted that the larger 211 particle radius, smaller volume fraction of the 211 particles, larger growth rate, or smaller imposed temperature gradient would cause easy occurrence of the constitutional undercooling ahead of the 123 growth interface. Taking into account the nucleation at the L/211 interface just ahead of the 123 growth front due to the constitutional undercooling, the transition of 123 growth from a planar-interface morphology to an equiaxed blocky morphology was investigated quantitatively and qualitatively

  18. Contradictory "Others" and the "Habitus" of Languages: Surveying the L2 Motivation Landscape in the United Kingdom

    Science.gov (United States)

    Lanvers, Ursula

    2017-01-01

    Britain's already poor record for language learning might be exacerbated by the Global English phenomenon, in that utilitarian reasons for learning languages other than English are increasingly undermined (Lanvers, 2014; Lo Bianco, 2014). This article offers a state-of-the-art review of UK research on second language (L2) learning motivation and…

  19. Effects of Interactive Chat versus Independent Writing on L2 Learning

    Science.gov (United States)

    Tare, Medha; Golonka, Ewa M.; Vatz, Karen; Bonilla, Carrie L.; Crooks, Carolyn; Strong, Rachel

    2014-01-01

    This study examines the importance of interaction for second language (L2) acquisition by analyzing outcomes from two types of out-of-class activities. The study compared: (a) interactive homework, completed via text chat, and (b) individual homework, completed via independent writing. In a between-subjects design, participants in two…

  20. Morphology Independent Learning in Modular Robots

    DEFF Research Database (Denmark)

    Christensen, David Johan; Bordignon, Mirko; Schultz, Ulrik Pagh

    2009-01-01

    Hand-coding locomotion controllers for modular robots is difficult due to their polymorphic nature. Instead, we propose to use a simple and distributed reinforcement learning strategy. ATRON modules with identical controllers can be assembled in any configuration. To optimize the robot’s locomotion...... speed its modules independently and in parallel adjust their behavior based on a single global reward signal. In simulation, we study the learning strategy’s performance on different robot configurations. On the physical platform, we perform learning experiments with ATRON robots learning to move as fast...

  1. A Review of Multimedia Glosses and Their Effects on L2 Vocabulary Acquisition in CALL Literature

    Science.gov (United States)

    Mohsen, Mohammed Ali; Balakumar, M.

    2011-01-01

    This article reviews the literature of multimedia glosses in computer assisted language learning (CALL) and their effects on L2 vocabulary acquisition during the past seventeen years. Several studies have touched on this area to examine the potential of multimedia in a CALL environment in aiding L2 vocabulary acquisition. In this review, the…

  2. L2 Learners' Recognition of Unfamiliar Idioms Composed of Familiar Words

    Science.gov (United States)

    Kim, Choonkyong

    2016-01-01

    Most second language (L2) learners are aware of the importance of vocabulary, and this awareness usually directs their attention to learning new words. By contrast, learners do not often recognise unfamiliar idioms if all the compositional parts look familiar to them such as "turn the corner" or "carry the day." College-level…

  3. The Role of Emergent Bilingualism in the Development of Morphological Awareness in Arabic and Hebrew

    Science.gov (United States)

    Schwartz, Mila; Taha, Haitham; Assad, Hanan; Khamaisi, Ferdos; Eviatar, Zohar

    2016-01-01

    Purpose: The purpose of the present study was to investigate the role of dual language development and cross-linguistic influence on morphological awareness in young bilinguals' first language (L1) and second language (L2). We examined whether (a) the bilingual children (L1/L2 Arabic and L1/L2 Hebrew) precede their monolingual Hebrew- or…

  4. English L3 Learning in a Multilingual Context: The Role of Parental Education and L2 Exposure within the Living Community

    Science.gov (United States)

    De Angelis, Gessica

    2015-01-01

    The present study examines two factors in relation to English L3 proficiency development and school performance in a third language: (a) parental education and (b) second language exposure within the living community. Participants (n?=?50) are Italian L1 students with German L2 and English L3. All students (eighth grade, 14 years of age) were…

  5. L’italiano L2 : auto-apprendimento e narratività. Materiali multimediali di italiano L2 per bambini e ragazzi.

    Directory of Open Access Journals (Sweden)

    Graziella Favaro

    2009-12-01

    basano su un forte impianto narrativo che sviluppa coinvolgimento e identificazione; d sono attenti allo sviluppo della lingua orale e dello scritto, dell'italiano per comunicare e per lo studio; e hanno una chiara caratterizzazione interculturale.  Normal 0 14 MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabella normale"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} Teaching Italian as a second language to newly immigrated children and young people is a delicate and complex undertaking which has become part of the job for teachers working in increasingly multicultural and multilingual classes.  The most widespread and effective way of teaching/learning the L2 is the integrated approach: the non-Italian-speaking child is placed in an ordinary class and, parallel to this, there are times when (she attends a workshop of Italian as a second language.  To support this integrated approach and accompany the new arrivals in their journey into the Italian language, flexible teaching/learning materials are needed, with a wealth of suggestions that can be used independently and with a small group; they should be suitable for use either traditionally or through LIM and appropriate for developing different competences in the language of communication, written Italian and preparation for learning in the core curriculum.  The two courses of Italian as L2 presented in the final part of the article satisfy these demands since a the former is intended for newly-arrived children from abroad and the latter for newly-arrived young people; b they are intended for the shift from pre-elementary to levels A1, A2 and B1 of the QCERL; c they are founded on a solid narrative basis which develops involvement and identification; d they

  6. Plaque Tissue Morphology-Based Stroke Risk Stratification Using Carotid Ultrasound: A Polling-Based PCA Learning Paradigm.

    Science.gov (United States)

    Saba, Luca; Jain, Pankaj K; Suri, Harman S; Ikeda, Nobutaka; Araki, Tadashi; Singh, Bikesh K; Nicolaides, Andrew; Shafique, Shoaib; Gupta, Ajay; Laird, John R; Suri, Jasjit S

    2017-06-01

    Severe atherosclerosis disease in carotid arteries causes stenosis which in turn leads to stroke. Machine learning systems have been previously developed for plaque wall risk assessment using morphology-based characterization. The fundamental assumption in such systems is the extraction of the grayscale features of the plaque region. Even though these systems have the ability to perform risk stratification, they lack the ability to achieve higher performance due their inability to select and retain dominant features. This paper introduces a polling-based principal component analysis (PCA) strategy embedded in the machine learning framework to select and retain dominant features, resulting in superior performance. This leads to more stability and reliability. The automated system uses offline image data along with the ground truth labels to generate the parameters, which are then used to transform the online grayscale features to predict the risk of stroke. A set of sixteen grayscale plaque features is computed. Utilizing the cross-validation protocol (K = 10), and the PCA cutoff of 0.995, the machine learning system is able to achieve an accuracy of 98.55 and 98.83%corresponding to the carotidfar wall and near wall plaques, respectively. The corresponding reliability of the system was 94.56 and 95.63%, respectively. The automated system was validated against the manual risk assessment system and the precision of merit for same cross-validation settings and PCA cutoffs are 98.28 and 93.92%for the far and the near wall, respectively.PCA-embedded morphology-based plaque characterization shows a powerful strategy for risk assessment and can be adapted in clinical settings.

  7. Dispersion and Frequency: Is There Any Difference as Regards Their Relation to L2 Vocabulary Gains?

    Science.gov (United States)

    Alcaraz-Mármol, Gema

    2015-01-01

    Despite the current importance given to L2 vocabulary acquisition in the last two decades, considerable deficiencies are found in L2 students' vocabulary size. One of the aspects that may influence vocabulary learning is word frequency. However, scholars warn that frequency may lead to wrong conclusions if the way words are distributed is ignored.…

  8. Help Options for L2 Listening in CALL: A Research Agenda

    Science.gov (United States)

    Cross, Jeremy

    2017-01-01

    In this article, I present an agenda for researching help options for second language (L2) listening in computer-assisted language learning (CALL) environments. I outline several theories which researchers in the area draw on, then present common points of concern identified from a review of related literature. This serves as a means to…

  9. Proceedings of the 2nd Workshop on Awareness and Reflection in Technology-Enhanced Learning

    NARCIS (Netherlands)

    Moore, Adam; Pammer, Viktoria; Pannese, Lucia; Prilla, Michael; Rajagopal, Kamakshi; Reinhardt, Wolfgang; Ullman, Thomas; Voigt, Christian

    2013-01-01

    Moore, A., Pammer, V., Pannese, L., Prilla, M., Rajagopal, K., Reinhardt, W., Ullman, Th. D., & Voigt, Ch. (Eds.) (2012). Proceedings of the 2nd Workshop on Awareness and Reflection in Technology Enhanced Learning. In conjunction with the 7th European Conference on Technology Enhanced Learning: 21st

  10. Literary Language in Development of L2 Competence

    Directory of Open Access Journals (Sweden)

    Dan Lu

    2012-11-01

    Full Text Available Nowadays it is believed that language in daily communication rather than literary language should be the target of learning in L2 education. This is mainly because literary language is said to be uncommon in life. This paper reports on a study in which some Hong Kong ESL learners’ English proficiency was re-examined through literary texts. These learners had reached intermediate or advanced levels of English prior to the study and were generally competent in daily English. However, many of them encountered difficulty in understanding literary language. Their proficiency in general English test could not match their performances in understanding literary works. The findings reveal that learners who are strong in general proficiency may not be good in understanding literary language. Lack of literary language in the curriculum results in a false and distorted picture about the learners’ proficiency. Literary language helps upgrade L2 learners’ real proficiency in the target language.

  11. Morphological Errors in Spanish Second Language Learners and Heritage Speakers

    Science.gov (United States)

    Montrul, Silvina

    2011-01-01

    Morphological variability and the source of these errors have been intensely debated in SLA. A recurrent finding is that postpuberty second language (L2) learners often omit or use the wrong affix for nominal and verbal inflections in oral production but less so in written tasks. According to the missing surface inflection hypothesis, L2 learners…

  12. Learner Characteristics, Learner Achievement and Time Investment in Online Courses for Dutch L2 in Adult Education

    Science.gov (United States)

    De Paepe, Liesbeth; Zhu, Chang; Depryck, Koen

    2018-01-01

    For the growing group of adult migrants, flexible solutions for second language (L2) acquisition are increasingly important, while concerns about the efficacy of online language learning abound. This study on the L2 situation in Flanders has 4 key aims: analyzing adult learner profiles in fully online Dutch beginners' courses; comparing learner…

  13. Stem characteristics of two forage maize (Zea mays L.) cultivars varying in whole plant digestibility. I. Relevant morphological parameters

    NARCIS (Netherlands)

    Boon, E.J.M.C.; Engels, F.M.; Struik, P.C.; Cone, J.W.

    2005-01-01

    The morphology and rumen fermentation kinetics of the maize cultivars (Zea mays L.) Vitaro and Volens were investigated in detail throughout their growing period as a first step towards understanding the relation between plant characteristics and cell wall fermentability of forage maize. Vitaro is

  14. The Multi-Feature Hypothesis: Connectionist Guidelines for L2 Task Design

    Science.gov (United States)

    Moonen, Machteld; de Graaff, Rick; Westhoff, Gerard; Brekelmans, Mieke

    2014-01-01

    This study focuses on the effects of task type on the retention and ease of activation of second language (L2) vocabulary, based on the multi-feature hypothesis (Moonen, De Graaff, & Westhoff, 2006). Two tasks were compared: a writing task and a list-learning task. It was hypothesized that performing the writing task would yield higher…

  15. Morphological and Metabolic Parameters of Red Blood Cells after Their Treatment with Ozone

    Directory of Open Access Journals (Sweden)

    Anna V. Deryugina

    2018-01-01

    Full Text Available The purpose of the study was to assess the morphology of red blood cells (RBC and the association of morphological parameters with lipid peroxidation processes and the content of organic phosphates in RBC when treating packed red blood cells with the ozonized saline solution (with an ozone concentration of 2 mg/l after different storage periods.Materials and methods. The morphology of human RBC, the concentration of malonic dialdehyde (MDA in RBC, the catalase activity, the concentration of ATP and 2,3-diphosphoglycerate (2,3-DPG were studied before and after treatment of RBC with the ozonized saline (with the ozone concentration of 2 mg/l after 7, 14, 21 and 30 days of storage.Results. The effect of ozone (2 ng/l in vitro on the packed red blood cells after 7–21 days of storage contributed to the recovery of RBC shape, increased the concentration of ATP and 2,3-DPG, and optimized the lipid peroxidation. Ozone did not demonstrate a pronounced positive effect on these parameters when the packed RBCs were stored for 30 days.Conclusion. The treatment of the packed RBCs with the ozonized saline solution (with the ozone concentration of 2 mg/l contributed to the recovery of the discocyte count due to optimization of lipid peroxidation processes in cell membranes and enhanced the synthesis of organic phosphates in cells due to the activation of glycolysis and the pentose phosphate pathway. This can be used to improve the morphological and metabolic status of the packed RBCs before their transfusion. 

  16. A preliminary Analysis of Dörnyei and Otto’s Process Model of L2 Motivation

    Institute of Scientific and Technical Information of China (English)

    徐佳佳

    2015-01-01

    In the past few decades, motivation has already become a recurring topic in SLA field, where motivational theories have placed great influence on language teaching. Different from previous motivation theories, Dörnyei and Otto’s process model of L2 motivation focuses on the dynamicity of motivation.This paper aims at analyzing the process model of L2 motivation and proposing stimulation strategies for each phase to attain learning effect.

  17. A preliminary Analysis of Drnyei and Otto’s Process Model of L2 Motivation

    Institute of Scientific and Technical Information of China (English)

    徐佳佳

    2015-01-01

    In the past few decades, motivation has already become a recurring topic in SLA field, where motivational theories have placed great influence on language teaching.Different from previous motivation theories, Drnyei and Otto’s process model of L2 motivation focuses on the dynamicity of motivation.This paper aims at analyzing the process model of L2 motivation and proposing stimulation strategies for each phase to attain learning effect.

  18. Morphological and Biochemical Characteristics of Fruits of Different Cornelian Cherry (Cornus mas L. Genotypes from Spontaneous Flora

    Directory of Open Access Journals (Sweden)

    Felicia-Constantina CORNESCU

    2017-12-01

    Full Text Available The current study was carried out on six local cornelian cherry (Cornus mas L. genotypes, grown in Turceni town (Gorj county and Baita village (Hunedoara county, in Romania. Several morphological and biochemical characteristics of cultivars were determined. Fruit weight and fruit flesh ratio of the analyzed genotypes ranged from 1.33 to 2.31 g and 61.53 to 78.58% respectively. Soluble solid contents were determined, the lowest noted as 10% and the highest as 25.5%. Results have shown that there was a high diversity in cornelian cherry populations within different ecological areas. Differences were exhibited in terms of fruit size and biochemical characteristics. The results of the study are useful for attempting to select superior genotypes of cornelian cherry for culture.

  19. Second Language Idiom Learning in a Paired-Associate Paradigm: Effects of Direction of Learning, Direction of Testing, Idiom Imageability, and Idiom Transparency

    Science.gov (United States)

    Steinel, Margarita P.; Hulstijn, Jan H.; Steinel, Wolfgang

    2007-01-01

    In a paired-associate learning (PAL) task, Dutch university students (n = 129) learned 20 English second language (L2) idioms either receptively or productively (i.e., L2-first language [L1] or L1-L2) and were tested in two directions (i.e., recognition or production) immediately after learning and 3 weeks later. Receptive and productive…

  20. L2 Learners' Assessments of Accentedness, Fluency, and Comprehensibility of Native and Nonnative German Speech

    Science.gov (United States)

    O'Brien, Mary Grantham

    2014-01-01

    In early stages of classroom language learning, many adult second language (L2) learners communicate primarily with one another, yet we know little about which speech stream characteristics learners tune into or the extent to which they understand this lingua franca communication. In the current study, 25 native English speakers learning German as…

  1. L’apprendimento della lingua della medicina in L2: due manuali a confronto

    Directory of Open Access Journals (Sweden)

    Maria Polita

    2013-07-01

    Full Text Available Insegnare la lingua speciale della medicina ad una classe di apprendenti L2 implica considerare diverse problematiche relative alle peculiarità del codice settoriale (variazioni diafasiche, particolarità del lessico, tecnicismi collaterali, ma anche relative al pubblico di apprendenti non italofono (tipologia, interessi, livello di apprendimento. Il panorama editoriale italiano offre pochi strumenti dedicati: tra questi Donatella Troncarelli, Dica 33. Il linguaggio della medicina, Bonacci, 1994 e Daniela Forapani, Italiano per medici, Alma edizioni, 2004. Questo studio intende mettere a confronto i due testi sottolineandone le caratteristiche e l’impostazione glottodidattica ed evidenziando come il contenuto linguistico sia proposto, quali siano le abilità favorite, quali gli obiettivi di apprendimento e quali gli strumenti forniti. Particolare attenzione viene prestata al lessico registrato nei glossari dei volumi.  Learning the language of medicine in l2: a comparison of two textbooks Teaching the special language of medicine to a class of L2 learners implies considering various issues related to the peculiarities of the sector-specific jargon (diphasic variations, peculiarities of vocabulary, collateral technicalities, also related to non-Italian-speaking learners (type, interests, level of learning. Italian publishers offer few dedicated tools: these include Donatella Troncarelli, Dica 33.Il linguaggio della medicina, Bonacci, 1994 and Daniela Forapani, Italiano per medici, Alma editions, 2004. This study aims to compare the two texts, highlighting their features and language teaching setting, showing how linguistic content is proposed, which skills are promoted, what the learning objectives are and what tools are provided. Particular attention is paid to the vocabulary in the glossaries.

  2. Karyological investigations on Erigeron canadensis L. and E. annuus (L. Pers. from natural stands in Poland

    Directory of Open Access Journals (Sweden)

    K. Bijok

    2015-01-01

    Full Text Available The number of chromosomes in metaphases root meristems of Erigeron canadensis L. (2n= 18 and E. annuus (L. Pers. (2n=27 was determined. The chromosomes of both species showed a morphological differentiation - they were heterobrachial or isobrachial; E. annuus had an additional unpaired isobrachial chromosome.

  3. The role of oral corrective feedback in L2 Portuguese classrooms

    Directory of Open Access Journals (Sweden)

    Bárbara Battistelli Rauber

    2017-11-01

    Full Text Available Languages are generally acquired along with and for others, in varied environments which influence second language (L2 learning. One of the most important influences of the linguistic environment is that it provides learners with information about the incorrectness of their utterances (ORTEGA, 2009. This process is referred as Corrective Feedback (LYSTER; RANTA, 1997, RUSSEL; SPADA, 2006, which is a complex phenomenon that has different functions in formal L2 instruction. The purpose of the current study was to investigate the types of oral CF in L2 Portuguese classrooms and to analyze how learners responded to CF provided by their teachers. The data presented were obtained from the observation of lessons in an elementary and an intermediate group of a Portuguese course offered at a private American university. The results of this observational study show that elicitation, explicit correction and metalinguistic feedback are the main CF methods employed by the teachers.

  4. Online multilingual vocabulary system and its application in L2 learning

    Directory of Open Access Journals (Sweden)

    Haruko Miyakoda

    2010-06-01

    Full Text Available In the field of second language teaching, vocabulary has been one of the most neglected areas in the classroom. Although language teachers/ instructors are well aware of the importance of vocabulary, there is not enough time in the classroom to actually “teach” vocabulary. Therefore, we need to find ways to promote autonomous vocabulary learning so that students can make good use of their time outside theclassrooms.In this study, we present an online vocabulary learning system that we have developed. The results obtained from our evaluation experiment indicate that our system is more effective in retaining the meaning of the words compared to the traditional learning method.As an example of applying this system to language learning, we will give a demonstration of a Japanese onomatopoeia dictionary that we are compiling. Onomatopoeia are especially troublesome for learners of the Japanese language. Although they are frequently used in both written and spoken Japanese, they are very difficult to translate to other languages. We demonstrate that by employing our system, learners are better able to understand the meaning and the context of eachlexical item.

  5. Cooperative Learning i voksenundervisningen – planlægning og gennemførelse af dynamiske og samarbejdende læreprocesser

    DEFF Research Database (Denmark)

    Nielsen, Lone; Christensen, Lars

    2018-01-01

    Om cooperative learning som læringsteknologi i voksenundervisningen, blikke fra underviser- og deltagerpespektiv......Om cooperative learning som læringsteknologi i voksenundervisningen, blikke fra underviser- og deltagerpespektiv...

  6. Morphological processing with deficient phonological short-term memory.

    Science.gov (United States)

    Kavé, Gitit; Ze'ev, Hagit Bar; Lev, Anita

    2007-07-01

    This paper investigates the processing of Hebrew derivational morphology in an individual (S.E.) with deficient phonological short-term memory. In comparison to 10 age- and education-matched men, S.E. was impaired on digit span tasks and demonstrated no recency effect in word list recall. S.E. had low word retention span, but he exhibited phonological similarity and word length effects. His ability to make lexical decisions was intact. In a paired-associate test S.E. successfully learned semantically and morphologically related pairs but not phonologically related pairs, and his learning of nonwords was facilitated by the presence of Hebrew consonant roots. Semantic and morphological similarity enhanced immediate word recall. Results show that S.E. is capable of conducting morphological decomposition of Hebrew-derived words despite his phonological deficit, suggesting that transient maintenance of morphological constituents is independent of temporary storage and rehearsal of phonological codes, and that each is processed separately within short-term memory.

  7. Morphological traits based diversity in safflower (carthamus tinctorius L.)

    International Nuclear Information System (INIS)

    Shinwari, Z.K.; Rehman, H.

    2014-01-01

    Safflower (Carthamus tinctorius L.) one of the world minor oil crops originated in the Middle East. The breeding potential of the safflower genotypes held in the gene-bank of Plant Genetic Resources Institute (PGRI) has not been exploited to date. Present work was carried out to evaluate 122 genotypes collected from various eco-geographical regions/countries of the world. Observations were recorded for eleven quantitative and five qualitative characters to estimate substantial variation and relationship among the genotypes and identify promising accession(s) for traits of economic significance. A significant level of morphological diversity was noticed for a number of traits. The largest variation was recorded for capsules plant-1, seeds capsule-1, seed yield plant-1, plant height, days to flowering initiation and days to maturity. Relatively low level of variability was distinguished in 100-seed weight, capsule diameter, primary branches plant-1, days to flower completion, time of flowering, flower color, leaf shape and spininess. The correlation analysis indicated that seed diameter, capsules plant-1 and seeds capsule-1 had highly significant positive contribution to seed yield plant-1. Only one trait, time of flowering showed negative correlation with seed yield plant-1. Principal component (PC) analysis of 122 safflower germplasm displayed significant variation with PC1 having 26.02% of the total variation, 19.97% for PC2, 12.38% for PC3 and PC4 contributed 11.24% of the total variation and revealed that the characters that mainly distinguish the germplasm are: capsule diameter, capsules plant-1, seeds capsule-1, days to maturity, plant height and time of flowering. Cluster analysis recognized five major clusters. Our findings have an important application for safflower germplasm evaluation and preservation. (author)

  8. Electrode Potentials of l-Tryptophan, l-Tyrosine, 3-Nitro-l-tyrosine, 2,3-Difluoro-l-tyrosine, and 2,3,5-Trifluoro-l-tyrosine.

    Science.gov (United States)

    Mahmoudi, Leila; Kissner, Reinhard; Nauser, Thomas; Koppenol, Willem H

    2016-05-24

    Electrode potentials for aromatic amino acid radical/amino acid couples were deduced from cyclic voltammograms and pulse radiolysis experiments. The amino acids investigated were l-tryptophan, l-tyrosine, N-acetyl-l-tyrosine methyl ester, N-acetyl-3-nitro-l-tyrosine ethyl ester, N-acetyl-2,3-difluoro-l-tyrosine methyl ester, and N-acetyl-2,3,5-trifluoro-l-tyrosine methyl ester. Conditional potentials were determined at pH 7.4 for all compounds listed; furthermore, Pourbaix diagrams for l-tryptophan, l-tyrosine, and N-acetyl-3-nitro-l-tyrosine ethyl ester were obtained. Electron transfer accompanied by proton transfer is reversible, as confirmed by detailed analysis of the current waves, and because the slopes of the Pourbaix diagrams obey Nernst's law. E°'(Trp(•),H(+)/TrpH) and E°'(TyrO(•),H(+)/TyrOH) at pH 7 are 0.99 ± 0.01 and 0.97 ± 0.01 V, respectively. Pulse radiolysis studies of two dipeptides that contain both amino acids indicate a difference in E°' of approximately 0.06 V. Thus, in small peptides, we recommend values of 1.00 and 0.96 V for E°'(Trp(•),H(+)/TrpH) and E°'(TyrO(•),H(+)/TyrOH), respectively. The electrode potential of N-acetyl-3-nitro-l-tyrosine ethyl ester is higher, while because of mesomeric stabilization of the radical, those of N-acetyl-2,3-difluoro-l-tyrosine methyl ester and N-acetyl-2,3,5-trifluoro-l-tyrosine methyl ester are lower than that of tyrosine. Given that the electrode potentials at pH 7 of E°'(Trp(•),H(+)/TrpH) and E°'(TyrO(•),H(+)/TyrOH) are nearly equal, they would be, in principle, interchangeable. Proton-coupled electron transfer pathways in proteins that use TrpH and TyrOH are thus nearly thermoneutral.

  9. Assessment of genetic diversity in ragi [Eleusine coracana (L.) Gaertn] using morphological, RAPD and SSR markers.

    Science.gov (United States)

    Prabhu, Kalapad Santosh; Das, Anath Bandhu; Dikshit, Nilamani

    2018-04-25

    Finger millet (Eleusine coracana L. Gaertn., 2n=36) is one of the most important minor crops, commonly known as 'ragi' and used as a staple food grain in more than 25 countries including Africa and south Asia. Twenty-seven accessions of ragi were collected from different parts of India and were evaluated for morpho-genetic diversity studies. Simple sequence repeat (SSR) and random amplified polymorphic DNA (RAPD) markers were used for assessment of genetic diversity among 27 genotypes of E. coracana. High degree of similarity (90%) was obtained between 'IC49979A' and 'IC49974B' genotypes, whereas low level of similarity (9.09%) was found between 'IC204141' and 'IC49985' as evident in morphological and DNA markers. A total of 64 SSR and 301 RAPD amplicons were produced, out of which 87.50% and 77.20% DNA fragments showed polymorphism, respectively. The clustering pattern obtained among the genotypes corresponded well with their morphological and cytological data with a monophyletic origin of this species which was further supported by high bootstrap values and principal component analysis. Cluster analysis showed that ragi accessions were categorised into three distinct groups. Genotypes IC344761, IC340116, IC340127, IC49965 and IC49985 found accession specific in RAPD and SSR markers. The variation among ragi accessions might be used as potential source of germplasm for crop improvement.

  10. Measurements of Development in L2 Written Production: The Case of L2 Chinese

    Science.gov (United States)

    Jiang, Wenying

    2013-01-01

    This study investigates measures for second language (L2) writing development. A T-unit, which has been found the most satisfactory unit of analysis for measuring L2 development in English, is extended to measure L2 Chinese writing development through a cross-sectional design in this study. Data were collected from three L2 Chinese learner groups…

  11. CANDELS: CONSTRAINING THE AGN-MERGER CONNECTION WITH HOST MORPHOLOGIES AT z {approx} 2

    Energy Technology Data Exchange (ETDEWEB)

    Kocevski, Dale D.; Faber, S. M.; Mozena, Mark; Trump, Jonathan R.; Koo, David C. [University of California Observatories/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Koekemoer, Anton M.; Somerville, Rachel S.; Lotz, Jennifer M.; Dahlen, Tomas; Donley, Jennifer L. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Nandra, Kirpal; Brusa, Marcella; Wuyts, Stijn [Max-Planck-Institut fuer extraterrestrische Physik, D-85748 Garching (Germany); Rangel, Cyprian; Laird, Elise S. [Astrophysics Group, Imperial College London, London, SW7 2AZ (United Kingdom); Bell, Eric F. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Alexander, David M. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Bournaud, Frederic [CEA, IRFU, SAp and Laboratoire AIM Paris-Saclay, F-91191 Gif-sur-Yvette (France); Conselice, Christopher J. [Centre for Astronomy and Particle Theory, University of Nottingham, Nottingham, NG7 2RD (United Kingdom); Dekel, Avishai, E-mail: kocevski@ucolick.org [Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); and others

    2012-01-10

    Using Hubble Space Telescope/WFC3 imaging taken as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, we examine the role that major galaxy mergers play in triggering active galactic nucleus (AGN) activity at z {approx} 2. Our sample consists of 72 moderate-luminosity (L{sub X} {approx} 10{sup 42-44} erg s{sup -1}) AGNs at 1.5 < z < 2.5 that are selected using the 4 Ms Chandra observations in the Chandra Deep Field South, the deepest X-ray observations to date. Employing visual classifications, we have analyzed the rest-frame optical morphologies of the AGN host galaxies and compared them to a mass-matched control sample of 216 non-active galaxies at the same redshift. We find that most of the AGNs reside in disk galaxies (51.4{sup +5.8}{sub -5.9}%), while a smaller percentage are found in spheroids (27.8{sup +5.8}{sub -4.6}%). Roughly 16.7{sup +5.3}{sub -3.5}% of the AGN hosts have highly disturbed morphologies and appear to be involved in a major merger or interaction, while most of the hosts (55.6{sup +5.6}{sub -5.9}%) appear relatively relaxed and undisturbed. These fractions are statistically consistent with the fraction of control galaxies that show similar morphological disturbances. These results suggest that the hosts of moderate-luminosity AGNs are no more likely to be involved in an ongoing merger or interaction relative to non-active galaxies of similar mass at z {approx} 2. The high disk fraction observed among the AGN hosts also appears to be at odds with predictions that merger-driven accretion should be the dominant AGN fueling mode at z {approx} 2, even at moderate X-ray luminosities. Although we cannot rule out that minor mergers are responsible for triggering these systems, the presence of a large population of relatively undisturbed disk-like hosts suggests that the stochastic accretion of gas plays a greater role in fueling AGN activity at z {approx} 2 than previously thought.

  12. IL FILM A LEZIONE DI ITALIANO L2: GLI ESAMI AL CINEMA

    Directory of Open Access Journals (Sweden)

    Michela Albizzati

    2014-02-01

    L2? “Movies during Italian L2 Lessons: exams at the cinema” tries to answer these questions regarding the use of films in class and proposes an activity using clips from Italian films. Movies are social documents, vehicles for experiencing living, “situated” language and multi-sensory learning. The article sheds light on how L2 classes can benefit from the use of authentic audio-visual materials such as movies if properly selected and didacticized. From reflection to practice: after identifying objectives, target groups and their linguistic and communicative needs, an activity based on the using three didacticized clips centered on university oral exams is presented. Putting the linguistic-communicative needs of learners at the center shows that, if properly didacticized, a film or a clip constitutes extremely useful educational material for L2 learning, as well as an inexhaustible source of ideas from which the teacher can create original and stimulating educational activities which are not only linguistic but also intercultural.

  13. Genetic diversity analysis for agro-morphological and seed quality traits in rapeseed (brassica campestris l.)

    International Nuclear Information System (INIS)

    Yousuf, M.; Ajmal, S.U.; Munir, M.; Ghafoor, A.

    2011-01-01

    One hundred fourteen accessions of rapeseed (Brassica campestris L.) were evaluated at National Agricultural Research Centre, Islamabad, Pakistan using cluster and principal component analyses during 2005 and 2006. Cluster analysis based on fifteen agro-morphological and six seed quality traits, divided 114 accessions into six and five clusters during 2005 and 2006, respectively. The first seven and five PCs with eigenvalues > 1 contributed 74.09% and 66.08% of the variability amongst accessions during 2005 and 2006, respectively. Nine important characters contributed positively to first two PCs during both the years 2005 and 2006. (author)

  14. [Morphological observation on hypopus of Lepidoglyphus destructor by optical microscope].

    Science.gov (United States)

    Yong, H; Ning, T; Qiang, C; Chao-Pin, L I

    2017-07-03

    Objective To observe the external morphology of Lepidoglyphus destructor hypopus under an optical microscope. Methods The samples were collected in a store of Chinese medicinal herbs in Huainan City in September, 2016, the L. destructor and the hypopus were isolated, and then made of slide specimens. The slide samples were prepared and observed under an optical microscope. Results The L. destructor hypopus and protonymph were found. The inactive hypopus was oval in shape, the feet were not welldeveloped, there was a distinct transverse seam on its back, and there were 2 pairs of genital sensory organs. Conclusion The optical microscopy shows the morphological characteristics of L. destructor hypopus, which can provide the basis for the biological classification and the prevention.

  15. Effect of poly-α, γ, L-glutamic acid as a capping agent on morphology and oxidative stress-dependent toxicity of silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Stevanović M

    2011-11-01

    Full Text Available Magdalena Stevanović1, Branimir Kovačević2, Jana Petković3, Metka Filipič3, Dragan Uskoković11Institute of Technical Sciences of Serbian Academy of Sciences and Arts, 2Institute of General and Physical Chemistry, Belgrade, Serbia; 3Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Ljubljana, SloveniaAbstract: Highly stable dispersions of nanosized silver particles were synthesized using a straightforward, cost-effective, and ecofriendly method. Nontoxic glucose was utilized as a reducing agent and poly- α, γ, L-glutamic acid (PGA, a naturally occurring anionic polymer, was used as a capping agent to protect the silver nanoparticles from agglomeration and render them biocompatible. Use of ammonia during synthesis was avoided. Our study clearly demonstrates how the concentration of the capping agent plays a major role in determining the dimensions, morphology, and stability, as well as toxicity of a silver colloidal solution. Hence, proper optimization is necessary to develop silver colloids of narrow size distribution. The samples were characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and zeta potential measurement. MTT assay results indicated good biocompatibility of the PGA-capped silver nanoparticles. Formation of intracellular reactive oxygen species was measured spectrophotometrically using 2,7-dichlorofluorescein diacetate as a fluorescent probe, and it was shown that the PGA-capped silver nanoparticles did not induce intracellular formation of reactive oxygen species.Keywords: silver nanoparticles, poly-α, γ, L-glutamic, green synthesis, morphology, cytotoxicity

  16. Effects of UV Rays and Thymol/Thymus vulgaris L. Extract in an ex vivo Human Skin Model: Morphological and Genotoxicological Assessment.

    Science.gov (United States)

    Cornaghi, Laura; Arnaboldi, Francesca; Calò, Rossella; Landoni, Federica; Baruffaldi Preis, William Franz; Marabini, Laura; Donetti, Elena

    2016-01-01

    Ultraviolet (UV) radiation is the major environmental factor affecting functions of the skin. Compounds rich in polyphenols, such as Thymus vulgaris leaf extract and thymol, have been proposed for the prevention of UV-induced skin damage. We compared the acute effects induced by UVA and UVB rays on epidermal morphology and proliferation, cytotoxicity, and genotoxicity. Normal human skin explants were obtained from young healthy women (n = 7) after informed consent and cultured at the air-liquid interface overnight. After 24 h, the samples were divided in 2 groups: the former exposed to UVA (16 or 24 J/cm2) and the latter irradiated with UVB (0.24 or 0.72 J/cm2). One hour after the end of irradiation, supernatants were collected for evaluation of the lactate dehydrogenase activity. Twenty-four hours after UVB exposure, biopsies were processed for light and transmission electron microscopy analysis, proliferation, cytotoxicity, and genotoxicity. UVB and UVA rays induced early inhibition of cell proliferation and DNA damage compared to controls. In particular, UVB rays were always more cytotoxic and genotoxic than UVA ones. For this reason, we evaluated the effect of either T. vulgaris L. extract (1.82 µg/ml) or thymol (1 µg/ml) on all samples treated for 1 h before UVB irradiation. While Thymus had a protective action for all of the endpoints evaluated, the action of the extract was less pronounced on epidermal proliferation and morphological features. The results presented in this study could be the basis for investigating the mechanism of thymol and T. vulgaris L. extract against the damage induced by UV radiation. © 2016 S. Karger AG, Basel.

  17. Leveling L2 Texts through Readability: Combining Multilevel Linguistic Features with the CEFR

    Science.gov (United States)

    Sung, Yao-Ting; Lin, Wei-Chun; Dyson, Scott Benjamin; Chang, Kuo-En; Chen, Yu-Chia

    2015-01-01

    Selecting appropriate texts for L2 (second/foreign language) learners is an important approach to enhancing motivation and, by extension, learning. There is currently no tool for classifying foreign language texts according to a language proficiency framework, which makes it difficult for students and educators to determine the precise…

  18. Improving the Computational Morphological Analysis of a Swahili ...

    African Journals Online (AJOL)

    approach to the morphological analysis of Swahili. We particularly focus our discussion on its ability to retrieve lemmas for word forms and evaluate it as a tool for corpus-based dictionary compilation. Keywords: LEXICOGRAPHY, MORPHOLOGY, CORPUS ANNOTATION, LEMMATIZATION, MACHINE LEARNING, SWAHILI ...

  19. Effects of L-arginine and Nω-nitro-L-arginine methylester on learning and memory and α7 nAChR expression in the prefrontal cortex and hippocampus of rats

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ming Wei; Wei Yang; Li-Xia Liu; Wen-Xiu Qi

    2013-01-01

    Nitric oxide (NO) is a novel type of neurotransmitter that is closely associated with synaptic plasticity,learning and memory.In the present study,we assessed the effects of L-arginine and Nω-nitro-L-arginine methylester (L-NAME,a nitric oxide synthase inhibitor) on learning and memory.Rats were assigned to three groups receiving intracerebroventricular injections of L-Arg (the NO precursor),L-NAME,or 0.9% NaCI (control),once daily for seven consecutive days.Twelve hours after the last injection,they underwent an electric shock-paired Y maze test.Twenty-four hours later,the rats' memory of the safe illuminated arm was tested.After that,the levels of NO and α7 nicotinic acetylcholine receptor (α7 nAChR) in the prefrontal cortex and hippocampus were assessed using an NO assay kit,and immunohistochemistry and Western blots,respectively.We found that,compared to controls,L-Arg-treated rats received fewer foot shocks and made fewer errors to reach the learning criterion,and made fewer errors during the memory-testing session.In contrast,L-NAME-treated rats received more foot shocks and made more errors than controls to reach the learning criterion,and made more errors during the memory-testing session.In parallel,NO content in the prefrontal cortex and hippocampus was higher in L-Arg-treated rats and lower in L-NAME rats,compared to controls.Similarly,α7 nAChR immunoreactivity and protein expression in the prefrontal cortex and hippocampus were higher in L-Arg-treated rats and lower in L-NAME rats,compared to controls.These results suggest that the modulation of NO content in the brain correlates with α7 nAChR distribution and expression in the prefrontal cortex and hippocampus,as well as with learning and memory performance in the Y-maze.

  20. Effects of a common worldwide drink (Beer) on L-Phenylalanine and L-Tyrosine fibrillar assemblies

    Science.gov (United States)

    Banik, Debasis; Banerjee, Pavel; Sabeehuddin, Ghazi; Sarkar, Nilmoni

    2017-11-01

    In this letter, small amount of beer [0.42-2.08% (v/v)] is employed to investigate the fibril inhibition kinetics of 1 mM L-Phenylalanine and L-Tyrosine (relevant to disease condition) using Fluorescence Lifetime imaging Microscopy (FLIM), Field Emission Scanning Electron Microscopy (FESEM) and High Resolution Transmission Electron Microscopic (HR-TEM) techniques. Our results indicate that 1.67 and 0.42% of beer is sufficient for effective breakdown of L-Phe and L-Tyr assemblies, respectively. Quantitative information about fibril inhibition is obtained from Fluorescence Correlation Spectroscopic (FCS) measurements. We have shown that the morphology of L-Phe changes to L-Tyr in presence of 2,2‧-Bipyridine-3,3‧-diol (BP(OH)2).

  1. MIMO transmit scheme based on morphological perceptron with competitive learning.

    Science.gov (United States)

    Valente, Raul Ambrozio; Abrão, Taufik

    2016-08-01

    This paper proposes a new multi-input multi-output (MIMO) transmit scheme aided by artificial neural network (ANN). The morphological perceptron with competitive learning (MP/CL) concept is deployed as a decision rule in the MIMO detection stage. The proposed MIMO transmission scheme is able to achieve double spectral efficiency; hence, in each time-slot the receiver decodes two symbols at a time instead one as Alamouti scheme. Other advantage of the proposed transmit scheme with MP/CL-aided detector is its polynomial complexity according to modulation order, while it becomes linear when the data stream length is greater than modulation order. The performance of the proposed scheme is compared to the traditional MIMO schemes, namely Alamouti scheme and maximum-likelihood MIMO (ML-MIMO) detector. Also, the proposed scheme is evaluated in a scenario with variable channel information along the frame. Numerical results have shown that the diversity gain under space-time coding Alamouti scheme is partially lost, which slightly reduces the bit-error rate (BER) performance of the proposed MP/CL-NN MIMO scheme. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. 2-Fluoro-L-Fucose Is a Metabolically Incorporated Inhibitor of Plant Cell Wall Polysaccharide Fucosylation

    Science.gov (United States)

    Wallace, Ian S.

    2015-01-01

    The monosaccharide L-fucose (L-Fuc) is a common component of plant cell wall polysaccharides and other plant glycans, including the hemicellulose xyloglucan, pectic rhamnogalacturonan-I (RG-I) and rhamnogalacturonan-II (RG-II), arabinogalactan proteins, and N-linked glycans. Mutations compromising the biosynthesis of many plant cell wall polysaccharides are lethal, and as a result, small molecule inhibitors of plant cell wall polysaccharide biosynthesis have been developed because these molecules can be applied at defined concentrations and developmental stages. In this study, we characterize novel small molecule inhibitors of plant fucosylation. 2-fluoro-L-fucose (2F-Fuc) analogs caused severe growth phenotypes when applied to Arabidopsis seedlings, including reduced root growth and altered root morphology. These phenotypic defects were dependent upon the L-Fuc salvage pathway enzyme L-Fucose Kinase/ GDP-L-Fucose Pyrophosphorylase (FKGP), suggesting that 2F-Fuc is metabolically converted to the sugar nucleotide GDP-2F-Fuc, which serves as the active inhibitory molecule. The L-Fuc content of cell wall matrix polysaccharides was reduced in plants treated with 2F-Fuc, suggesting that this molecule inhibits the incorporation of L-Fuc into these polysaccharides. Additionally, phenotypic defects induced by 2F-Fuc treatment could be partially relieved by the exogenous application of boric acid, suggesting that 2F-Fuc inhibits RG-II biosynthesis. Overall, the results presented here suggest that 2F-Fuc is a metabolically incorporated inhibitor of plant cellular fucosylation events, and potentially suggest that other 2-fluorinated monosaccharides could serve as useful chemical probes for the inhibition of cell wall polysaccharide biosynthesis. PMID:26414071

  3. Do L2 Writing Courses Affect the Improvement of L1 Writing Skills via Skills Transfer from L2 to L1?

    Science.gov (United States)

    Gonca, Altmisdort

    2016-01-01

    This study investigates the relationship of second language (L2) writing skills proficiency with the first language (L1) writing skills, in light of the language transfer. The study aims to analyze the positive effects of L2 writing proficiency on L1 writing proficiency. Forty native Turkish-speaking university students participated in the study.…

  4. Teaching, Learning, and Developing L2 French Sociolinguistic Competence: A Sociocultural Perspective

    Science.gov (United States)

    van Compernolle, Remi A.; Williams, Lawrence

    2012-01-01

    The study reported in this article investigates the development of sociolinguistic competence among second-year (US university-level) L2 learners of French who were given systematic instruction on sociolinguistic variation as part of their normal coursework. We focus on the variable use of the negative morpheme "ne" in verbal negation. Drawing…

  5. Controllable synthesis of TiO2 nanomaterials by assisting with l-cysteine and ethylenediamine

    KAUST Repository

    Tao, Yugui

    2013-11-21

    This paper reports a facile l-cysteine-assisted solvothermal synthesis of TiO2 nanomaterials using ethylenediamine (En) and distilled water as solvent. The influence of reaction time, temperature, l-cysteine and solvent was initially investigated. Results demonstrated the reaction temperature, l-cysteine and En significantly imposed impact on the phase and morphology of the particles. Amorphous nanosheets, mixed-crystal nanorods and pure anatase nanoparticles were controllably synthesized by varying reaction temperature. The formation of the amorphous nanosheets and mixed-crystal nanorods were directly affected by the presence of l-cysteine and En. And the presence of En distinctly affected the crystal phase of the products, which was rarely mentioned in other studies. Moreover, the photocatalytic activities of three typical samples were excellent. The possible formation mechanism of the sample was also discussed. © 2013 Springer Science+Business Media New York.

  6. Controllable synthesis of TiO2 nanomaterials by assisting with l-cysteine and ethylenediamine

    KAUST Repository

    Tao, Yugui; Cao, Ning; Pan, Jun; Sun, Yichen; Jin, Cheng; Song, Yang

    2013-01-01

    This paper reports a facile l-cysteine-assisted solvothermal synthesis of TiO2 nanomaterials using ethylenediamine (En) and distilled water as solvent. The influence of reaction time, temperature, l-cysteine and solvent was initially investigated. Results demonstrated the reaction temperature, l-cysteine and En significantly imposed impact on the phase and morphology of the particles. Amorphous nanosheets, mixed-crystal nanorods and pure anatase nanoparticles were controllably synthesized by varying reaction temperature. The formation of the amorphous nanosheets and mixed-crystal nanorods were directly affected by the presence of l-cysteine and En. And the presence of En distinctly affected the crystal phase of the products, which was rarely mentioned in other studies. Moreover, the photocatalytic activities of three typical samples were excellent. The possible formation mechanism of the sample was also discussed. © 2013 Springer Science+Business Media New York.

  7. Quantitative assessment of cancer cell morphology and motility using telecentric digital holographic microscopy and machine learning.

    Science.gov (United States)

    Lam, Van K; Nguyen, Thanh C; Chung, Byung M; Nehmetallah, George; Raub, Christopher B

    2018-03-01

    The noninvasive, fast acquisition of quantitative phase maps using digital holographic microscopy (DHM) allows tracking of rapid cellular motility on transparent substrates. On two-dimensional surfaces in vitro, MDA-MB-231 cancer cells assume several morphologies related to the mode of migration and substrate stiffness, relevant to mechanisms of cancer invasiveness in vivo. The quantitative phase information from DHM may accurately classify adhesive cancer cell subpopulations with clinical relevance. To test this, cells from the invasive breast cancer MDA-MB-231 cell line were cultured on glass, tissue-culture treated polystyrene, and collagen hydrogels, and imaged with DHM followed by epifluorescence microscopy after staining F-actin and nuclei. Trends in cell phase parameters were tracked on the different substrates, during cell division, and during matrix adhesion, relating them to F-actin features. Support vector machine learning algorithms were trained and tested using parameters from holographic phase reconstructions and cell geometric features from conventional phase images, and used to distinguish between elongated and rounded cell morphologies. DHM was able to distinguish between elongated and rounded morphologies of MDA-MB-231 cells with 94% accuracy, compared to 83% accuracy using cell geometric features from conventional brightfield microscopy. This finding indicates the potential of DHM to detect and monitor cancer cell morphologies relevant to cell cycle phase status, substrate adhesion, and motility. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

  8. Phenetic relationships of nine varieties of potato (Solanum tuberosum L.) based on morphological characters

    Science.gov (United States)

    Hidayat, Topik; Barlian, Andri; Kusdianti, R.; Kirana, Rinda

    2017-05-01

    Potato (Solanum tuberosum L.; Solanaceae) is an important commodity in Indonesia as one of the main crop after rice. Recently some new varieties have been released, but their relationship have not been studied yet. The purpose of this research was to determine the relationship among nine varieties of potatoes. Phenetic analysis was conducted using 27 morphological character states, which was derived from stems, leaves, and tubers. The character states observed were scored, and further analyzed based on Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method. The results showed a high diversity of morphological character states, of which 20 states were significantly different across the varieties. Phenogram indicated that the nine varieties of potato were classified into three main groups. While the first group was consisted of varieties of Cipanas, Granola, Atlantic, and Repita, the second group was housed of Manohara and GM 05. The third group was composed of Margahayu, Mb 17, and Maglia. This pattern of relationships can be used as one of the basis in the process of crossbreeding to assemble the new varieties. The crossbreeding will be better if it is made between distantly related varieties.

  9. Intrafloral differentiation of stamen morphology and function of capparis spinosa L

    International Nuclear Information System (INIS)

    Linke, Y.; Meilin, Y.; Qiumei, C.

    2017-01-01

    In Capparis spinosa L. (Capparidaceae), a woody perennial with both male and perfect flowers on the same plant, each flower has both short and long stamens. Flowers of C. spinosa were examined for 2 years at the Turpan Eremophytes Botanical Garden in Xinjiang, China. Stamen morphological characteristics, pollen vigor, quantity of pollen, and insect visitation were compared for flowers with short and long stamens to ascertain the function of the two types of stamens. Both types of flowers, male and perfect flowers, had both long and short stamens in the same flower. The number of stamens and pollen grains as well as the color of filaments in a single flower were significantly different between long and short stamens. The number of pollen grains produced by long stamens in a flower was greater than those of shorter stamen in the same flower, although pollen vigor did not differ between pollen from long and short stamens. Insect visitation frequency was higher for long stamens than for short stamens. The pollen of long and short stamens was used for hand-pollination. The rates of fruit and seed set from the pollen of long stamens were higher than those from the pollen of short stamens. While the main function of long stamens was to provide pollen for visiting insects, short stamens might improve male resources in three ways: by providing a guaranteeof pollen availability in adverse weather conditions, increasingthe space available for pollen capture and increasing the visitation timeofindividual insects. (author)

  10. Pollen morphology of European bladderworts (Utricularia L., Lentibulariaceae)

    Czech Academy of Sciences Publication Activity Database

    Beretta, M.; Rodondi, G.; Adamec, Lubomír; Andreis, C.

    2014-01-01

    Roč. 205, č. 1 (2014), s. 22-30 ISSN 0034-6667 Institutional support: RVO:67985939 Keywords : Utricularia * pollen morphology * determination key Subject RIV: EF - Botanics Impact factor: 1.940, year: 2014

  11. When Learning English is Compulsory at School:

    Directory of Open Access Journals (Sweden)

    Maryam Azarnoosh

    2014-11-01

    Full Text Available Research findings highlight the role of motivation in the long-term process of learning a second/foreign language. One’s motivation can change even in a short period of time under the influence of multifarious factors. To enrich our understanding of the attitudinal/motivational basis of foreign language learning this study attempts to investigate L2 motivational fluctuation, and the possibility of predicting EFL learners’ motivated learning behavior in light of Dörnyei’s (2005, 2009 theory of L2 motivational self system. To this end, 1670 junior high and high school students studying English as a compulsory subject in Iran filled out L2 motivational self system questionnaire. Independent samples t-test and regression analyses were applied; and the findings indicated a higher motivational disposition for junior high school students in comparison to high school students, except for their attitudes towards L2 community. For both groups, attitudes towards L2 learning was the best predictor of students motivated learning behavior.

  12. The effect of tetraploidy induction on morphology and anatomy characteristics of Cannabis sativa L.

    Directory of Open Access Journals (Sweden)

    Hakimeh Mansouri

    2014-12-01

    Full Text Available The production of tetraploid plant was studied in Cannabis sativa L. with colchicine at three different concentrations (i.e., 0.0, 0.1 and 0.2% for about 24 and 48 h through dropping method. Flow cytometry analyses were used to confirm the ploidy level. Morphologic and anatomic characteristics between tetraploid and diploid control plants were compared. The results showed that 0.2% colchicine for 24 h had the best effect. The percentage of tetraploid plants and the survival rate were lowered by increasing the treatment time. In addition, the leaf index and height of tetraploid plants exhibited a significant decrease compared to the diploid plants. The size of leaves' epidermis stomata were larger in tetraploid plant compared to the diploid ones, in spite of their less density of stomata. However, the amount of total chlorophyll and carotenoids were almost the same in both of tetraploid and diploid plants. In addition, some differences were also observed in the cross section of stem of these plants from the descriptive structure point of view. On the whole, the results introduced usage of the stomata parameters as an effective and convenient method for detecting the tetraploid plants however, the flow cytometry analysis was more effective in assessing the ploidy percentage.

  13. Finding the key to successful L2 learning in groups and individuals

    NARCIS (Netherlands)

    Lowie, Wander; van Dijk, Marijn; Chan, HuiPing; Verspoor, Marjolijn

    A large body studies into individual differences in second language learning has shown that success in second language learning is strongly affected by a set of relevant learner characteristics ranging from the age of onset to motivation, aptitude, and personality. Most studies have concentrated on

  14. Second Language Learning: Investigating Domain-Specific Adaptation in Advanced L2 Production

    NARCIS (Netherlands)

    Kerz, E.; Wiechmann, D.

    2016-01-01

    Usage-based (UB) accounts conceive of language learning as continuous, locally contingent construction learning, i.e., a lifelong process of developing and honing the repertoire of constructional patterns geared to the optimization of a language user’s communicative ability across a wide range of

  15. Early child L2 acquisition: Age or input effects? Neither, or both?

    Science.gov (United States)

    Unsworth, Sharon

    2016-05-01

    This paper explores whether there is evidence for age and/or input effects in child L2 acquisition across three different linguistic domains, namely morphosyntax, vocabulary, and syntax-semantics. More specifically, it compares data from English-speaking children whose age of onset to L2 Dutch was between one and three years with data from children whose age of onset was between four and seven years in their acquisition of verb morphology, verb placement, vocabulary, and direct object scrambling. The main findings were that there were no significant differences between the two groups in any of these areas and, with the exception of scrambling, current amount of exposure was the only factor significantly related to children's scores. The paper discusses the theoretical significance of these findings with respect to the role of input in the language acquisition process and the claim that there is a critical period ending within (early) childhood.

  16. Cell dynamic morphology classification using deep convolutional neural networks.

    Science.gov (United States)

    Li, Heng; Pang, Fengqian; Shi, Yonggang; Liu, Zhiwen

    2018-05-15

    Cell morphology is often used as a proxy measurement of cell status to understand cell physiology. Hence, interpretation of cell dynamic morphology is a meaningful task in biomedical research. Inspired by the recent success of deep learning, we here explore the application of convolutional neural networks (CNNs) to cell dynamic morphology classification. An innovative strategy for the implementation of CNNs is introduced in this study. Mouse lymphocytes were collected to observe the dynamic morphology, and two datasets were thus set up to investigate the performances of CNNs. Considering the installation of deep learning, the classification problem was simplified from video data to image data, and was then solved by CNNs in a self-taught manner with the generated image data. CNNs were separately performed in three installation scenarios and compared with existing methods. Experimental results demonstrated the potential of CNNs in cell dynamic morphology classification, and validated the effectiveness of the proposed strategy. CNNs were successfully applied to the classification problem, and outperformed the existing methods in the classification accuracy. For the installation of CNNs, transfer learning was proved to be a promising scheme. © 2018 International Society for Advancement of Cytometry. © 2018 International Society for Advancement of Cytometry.

  17. Response morphology and anatomy of tobacco (Nicotiana tabacum L.) plant on waterlogging

    Science.gov (United States)

    Nurhidayati, Tutik; Wardhani, Selfrina Puri; Purnobasuki, Hery; Hariyanto, Sucipto; Jadid, Nurul; Nurcahyani, Desy Dwi

    2017-11-01

    This study has conducted research on morphological and anatomical responses of some varieties of tobacco plants to waterlogging stress. Parameters measured were morphology, anatomy, and plants sensitivity index. Results were analyzed using two-way ANOVA followed by the Tukey test. The results show that waterlogging stress can reduce the growth of tobacco plants, including a decrease in plant height with the lowest value of 15.6 cm, root length reduction to the lowest value of 4.6 cm and plant dry weight reduction to the lowest value of 0.26 gr. But waterlogging stress can increase the number of adventitious roots with the highest value of 18.33. In addition, waterlogging stress can lead to the formation of aerenchyma tissue. The sensitivity index showed that plant varieties that are resistant to waterlogging stress are the varieties Kemloko 3 (index value of 0.03), varieties of Paiton 2 (index value of 0.18), and the varieties Kemloko 2 (index value of 0.42).

  18. FROM STORYTELLING TO STORY WRITING: THE IMPLEMENTATION OF READING TO LEARN (R2L PEDAGOGY TO TEACH ENGLISH AS A FOREIGN LANGUAGE IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Ika Lestari Damayanti

    2017-01-01

    Full Text Available It is widely acknowledged that the use of stories supports the development of literacy in the context of learning English as a first language. However, it seems that there are a few studies investigating this issue in the context of teaching and learning English as a foreign language.  This action-oriented case study aims to enhance students’ written narrative achievement through a pedagogical intervention that incorporates oral story sharing activities. In this paper, the intervention will be briefly described and the preliminary findings from the students’ written texts will be presented. This study which was conducted in a lower secondary school in Bandung Barat region, Indonesia implemented the intervention within eight learning periods. The intervention comprised the following stages: (1 preparing before reading (stories, (2 detailed reading, (3 joint rewriting, and (4 individual rewriting. Before and after the intervention, students’ narrative texts were collected and analysed in terms of how each text achieved its purpose, how it moved through stages and phases of meaning, the control of field, relationship with the reader and its coherence.  The preliminary findings indicate that there is a shift in students’ ability from writing fragmented and spoken-like language to more literate written narratives.   It is expected that this study which implemented R2L pedagogy in the Indonesian context will contribute to English language teaching in EFL contexts.

  19. Effects of gamma radiation in a wide range of doses on the morphological characteristics of Lemna minor L

    International Nuclear Information System (INIS)

    Rasskazova, M.M.; Berestina, A.V.

    2011-01-01

    The effects of gamma radiation on the morphological parameters of Lemna minor L. were studied. As the sensitive parameters were invited to use chlorosis and necrosis. Significant differences between samples begin to show after 14 days of observation. The presence of effect, irrespective of the dose in the range 0,1-30 Gy, shows the efficiency of a sufficiently small dose (0,1 Gy) was revealed.

  20. Effects of a dragonfly (Anax i.) homeopathic remedy on learning, memory and cell morphology in mice.

    Science.gov (United States)

    Mutlu, Oguz; Ulak, Guner; Kokturk, Sibel; Komsuoglu Celikyurt, Ipek; Tanyeri, Pelin; Akar, Furuzan; Erden, Faruk

    2016-02-01

    Homeopathy is a form of alternative medicine in which uses highly diluted preparations that are believed to cause healthy people to exhibit symptoms similar to those exhibited by patients. The aim of this study was to investigate the effects of dragonfly (Anax imperator, Anax i.) on learning and memory in naive mice using the Morris water maze (MWM) test; moreover, the effects of dragonfly on MK-801-induced cognitive dysfunction were evaluated. Male balb-c mice were treated with dragonfly (30C and 200C) or MK-801 (0.2 mg/kg) alone or concurrently (n = 10). Dragonfly (D) and MK-801 were administered subchronically for 6 days intraperitoneally 60 min and 30 min, respectively, before the daily performance of the MWM test. This study revealed that in the familiarization session and first session of the MWM test, Anax i. D30 significantly decreased escape latency compared to the control group, although MK-801, D30 and D200 significantly increased escape latency at the end of five acquisition sessions. Anax i. combined with dizocilpine maleate (MK-801) also significantly decreased escape latency in the familiarization session and first session of the MWM test, although this combination increased escape latency compared to the MK-801 alone group at the end of the test. Time spent in escape platform's quadrant in the probe trial significantly decreased while mean distance to platform significantly increased in MK-801, D30 and D200 groups. In the MWM test, Anax i. combined with MK-801 significantly decreased speed of the animals compared to the MK-801 alone group. General cell morphology was disturbed in the MK-801 group while D30 and D200 seemed to improve cell damage in the MK-801 group. These results suggest that the homeopathic Anax i. can impair learning acquisition and reference memory, and it has beneficial effects on disturbed cell morphology. Copyright © 2015 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  1. Studies on Dasyaceae. 3. Towards a phylogeny of the Dasyaceae (Ceramiales, Rhodophyta), based on comparative rbcL gene sequences and morphology

    NARCIS (Netherlands)

    de Jong, Y.S D M; van der Wurff, A.W G; Stam, W.T.; Olsen, J.L.

    Phylogenetic analyses of the Dasyaceae based on sequence analysis of the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) and 42 morphological characters are presented. Comparative sequence analysis confirms the general view of the Ceramiaceae as a primitive, paraphyletic

  2. The Development of L2 Fluency during Study Abroad: A Cross-Language Study

    Science.gov (United States)

    Di Silvio, Francesca; Diao, Wenhao; Donovan, Anne

    2016-01-01

    Examining speech samples from 75 American university students learning 1 of 3 languages (Mandarin, Russian, and Spanish), this article reports on a study of second language (L2) learners' oral fluency development and its relationship with their gains in holistic proficiency ratings during a semester abroad. In study abroad research, there is a…

  3. Finding the Key to Successful L2 Learning in Groups and Individuals

    Science.gov (United States)

    Lowie, Wander; van Dijk, Marijn; Chan, Huiping; Verspoor, Marjolijn

    2017-01-01

    A large body studies into individual differences in second language learning has shown that success in second language learning is strongly affected by a set of relevant learner characteristics ranging from the age of onset to motivation, aptitude, and personality. Most studies have concentrated on a limited number of learner characteristics and…

  4. The Inhibitory Effects of Curcuma longa L. Essential Oil and Curcumin on Aspergillus flavus Link Growth and Morphology

    Science.gov (United States)

    Mossini, Simone Aparecida Galerani; Ferreira, Francine Maery Dias; Arrotéia, Carla Cristina; da Costa, Christiane Luciana; Nakamura, Celso Vataru; Machinski Junior, Miguel

    2013-01-01

    The essential oil from Curcuma longa L. was analysed by GC/MS. The major components of the oil were ar-turmerone (33.2%), α-turmerone (23.5%) and β-turmerone (22.7%). The antifungal activities of the oil were studied with regard to Aspergillus flavus growth inhibition and altered morphology, as preliminary studies indicated that the essential oil from C. longa inhibited Aspergillus flavus Link aflatoxin production. The concentration of essential oil in the culture media ranged from 0.01% to 5.0% v/v, and the concentration of curcumin was 0.01–0.5% v/v. The effects on sporulation, spore viability, and fungal morphology were determined. The essential oil exhibited stronger antifungal activity than curcumin on A. flavus. The essential oil reduced the fungal growth in a concentration-dependent manner. A. flavus growth rate was reduced by C. longa essential oil at 0.10%, and this inhibition effect was more efficient in concentrations above 0.50%. Germination and sporulation were 100% inhibited in 0.5% oil. Scanning electron microscopy (SEM) of A. flavus exposed to oil showed damage to hyphae membranes and conidiophores. Because the fungus is a plant pathogen and aflatoxin producer, C. longa essential oil may be used in the management of host plants. PMID:24367241

  5. The Inhibitory Effects of Curcuma longa L. Essential Oil and Curcumin on Aspergillus flavus Link Growth and Morphology

    Directory of Open Access Journals (Sweden)

    Flávio Dias Ferreira

    2013-01-01

    Full Text Available The essential oil from Curcuma longa L. was analysed by GC/MS. The major components of the oil were ar-turmerone (33.2%, α-turmerone (23.5% and β-turmerone (22.7%. The antifungal activities of the oil were studied with regard to Aspergillus flavus growth inhibition and altered morphology, as preliminary studies indicated that the essential oil from C. longa inhibited Aspergillus flavus Link aflatoxin production. The concentration of essential oil in the culture media ranged from 0.01% to 5.0% v/v, and the concentration of curcumin was 0.01–0.5% v/v. The effects on sporulation, spore viability, and fungal morphology were determined. The essential oil exhibited stronger antifungal activity than curcumin on A. flavus. The essential oil reduced the fungal growth in a concentration-dependent manner. A. flavus growth rate was reduced by C. longa essential oil at 0.10%, and this inhibition effect was more efficient in concentrations above 0.50%. Germination and sporulation were 100% inhibited in 0.5% oil. Scanning electron microscopy (SEM of A. flavus exposed to oil showed damage to hyphae membranes and conidiophores. Because the fungus is a plant pathogen and aflatoxin producer, C. longa essential oil may be used in the management of host plants.

  6. The inhibitory effects of Curcuma longa L. essential oil and curcumin on Aspergillus flavus link growth and morphology.

    Science.gov (United States)

    Dias Ferreira, Flávio; Mossini, Simone Aparecida Galerani; Dias Ferreira, Francine Maery; Arrotéia, Carla Cristina; da Costa, Christiane Luciana; Nakamura, Celso Vataru; Machinski, Miguel

    2013-01-01

    The essential oil from Curcuma longa L. was analysed by GC/MS. The major components of the oil were ar-turmerone (33.2%), α -turmerone (23.5%) and β -turmerone (22.7%). The antifungal activities of the oil were studied with regard to Aspergillus flavus growth inhibition and altered morphology, as preliminary studies indicated that the essential oil from C. longa inhibited Aspergillus flavus Link aflatoxin production. The concentration of essential oil in the culture media ranged from 0.01% to 5.0% v/v, and the concentration of curcumin was 0.01-0.5% v/v. The effects on sporulation, spore viability, and fungal morphology were determined. The essential oil exhibited stronger antifungal activity than curcumin on A. flavus. The essential oil reduced the fungal growth in a concentration-dependent manner. A. flavus growth rate was reduced by C. longa essential oil at 0.10%, and this inhibition effect was more efficient in concentrations above 0.50%. Germination and sporulation were 100% inhibited in 0.5% oil. Scanning electron microscopy (SEM) of A. flavus exposed to oil showed damage to hyphae membranes and conidiophores. Because the fungus is a plant pathogen and aflatoxin producer, C. longa essential oil may be used in the management of host plants.

  7. A review of theoretical perspectives on language learning and acquisition

    Directory of Open Access Journals (Sweden)

    Norbahira Mohamad Nor

    2018-01-01

    Full Text Available This paper reviews three main theoretical perspectives on language learning and acquisition in an attempt to elucidate how people acquire their first language (L1 and learn their second language (L2. Behaviorist, Innatist and Interactionist offer different perspectives on language learning and acquisition which influence the acceptance of how an L2 should be taught and learned. This paper also explicates the relationship between L1 and L2, and elaborates on the similarities and differences between the two. This paper concludes that there is no one solid linguistic theory which can provide the ultimate explanation of L1 acquisition and L2 learning as there are many interrelated factors that influence the success of language acquisition or language learning. The implication is that teachers should base their classroom management practices and pedagogical techniques on several theories rather than a single theory as learners learn and acquire language differently. It is hoped that this paper provides useful insights into the complex process involved in language acquisition and learning, and contributes to the increased awareness of the process among the stakeholders in the field of language education. Keywords: behaviorist, innatist, interactionist, language acquisition, second language learning

  8. De l'attrait des médias sociaux pour l'apprentissage des langues – Regard sur l'état de l'art On the attractiveness of social media for language learning: a look at the state of the art

    Directory of Open Access Journals (Sweden)

    Katerina Zourou

    2012-03-01

    Full Text Available Ce texte dresse l'arrière-plan contextuel et notionnel des articles retenus pour le numéro spécial "Médias sociaux et apprentissage des langues : (révolution ?". Il commence par une définition d'un certain nombre de termes qui dominent le discours actuel comme "médias sociaux", "web 2.0", "web social", "sites de réseautage social" et "communautés web 2.0 d'apprentissage des langues". L'objectif n'est pas de "réinventer la roue" en suggérant de nouvelles définitions mais de synthétiser les définitions dominantes et de les confronter à des concepts proches de la littérature du domaine de l'Alao. Sont ensuite discutés trois aspects clés des technologies du web 2.0 (participation de l'utilisateur, ouverture et effets de réseautage. Ces trois caractéristiques étaient, certes, déjà présentes avec les technologies qui ont précédé les médias sociaux, nous examinons donc en quoi elles prennent, ou non, un sens radicalement différent à l'ère des médias sociaux. Un certain nombre de pistes de recherche sont discutées dans la dernière partie du texte.This paper sets the stage for the articles selected for the special issue "language learning and social media: (revolution?". Starting with some definitions of mainstream terms like "social media", "web 2.0", "social web", "social networking sites (SNS" and "web 2.0 language learning communities". The purpose is not to "reinvent the wheel" by suggesting new definitions, but to synthesize definitions of mainstream terms and juxtapose them to similar concepts from CALL literature. We then critically discuss three key features of web 2.0 technologies (user participation, openness and network effects. Despite the fact that these three features were present to some extent in technologies prior to social media, we examine whether they take on a radically different meaning in the social media era. Research insights are discussed in the last section of the paper.

  9. 2-Fluoro-L-Fucose Is a Metabolically Incorporated Inhibitor of Plant Cell Wall Polysaccharide Fucosylation.

    Directory of Open Access Journals (Sweden)

    Jose A Villalobos

    Full Text Available The monosaccharide L-fucose (L-Fuc is a common component of plant cell wall polysaccharides and other plant glycans, including the hemicellulose xyloglucan, pectic rhamnogalacturonan-I (RG-I and rhamnogalacturonan-II (RG-II, arabinogalactan proteins, and N-linked glycans. Mutations compromising the biosynthesis of many plant cell wall polysaccharides are lethal, and as a result, small molecule inhibitors of plant cell wall polysaccharide biosynthesis have been developed because these molecules can be applied at defined concentrations and developmental stages. In this study, we characterize novel small molecule inhibitors of plant fucosylation. 2-fluoro-L-fucose (2F-Fuc analogs caused severe growth phenotypes when applied to Arabidopsis seedlings, including reduced root growth and altered root morphology. These phenotypic defects were dependent upon the L-Fuc salvage pathway enzyme L-Fucose Kinase/ GDP-L-Fucose Pyrophosphorylase (FKGP, suggesting that 2F-Fuc is metabolically converted to the sugar nucleotide GDP-2F-Fuc, which serves as the active inhibitory molecule. The L-Fuc content of cell wall matrix polysaccharides was reduced in plants treated with 2F-Fuc, suggesting that this molecule inhibits the incorporation of L-Fuc into these polysaccharides. Additionally, phenotypic defects induced by 2F-Fuc treatment could be partially relieved by the exogenous application of boric acid, suggesting that 2F-Fuc inhibits RG-II biosynthesis. Overall, the results presented here suggest that 2F-Fuc is a metabolically incorporated inhibitor of plant cellular fucosylation events, and potentially suggest that other 2-fluorinated monosaccharides could serve as useful chemical probes for the inhibition of cell wall polysaccharide biosynthesis.

  10. Initiating round robins in the L2 classroom - preliminary observations

    DEFF Research Database (Denmark)

    Mortensen, Kristian; Hazel, Spencer

    2011-01-01

    Complementing recent interactional research on the contingent operation of online task accomplishment, this paper deals with a specific way of organizing and managing tasks in plenary L2 classrooms – namely the round robin. This may seem like a “traditional” and rigid form of classroom organizati...... and artefacts and graphic structures that are used not only as mediating tools in the (supposed) learning relevant activity, but also as structurally relevant features to organize the ongoing interaction, in which these activities emerge....

  11. Smoke produced from plants waste material elicits growth of wheat (Triticum aestivum L. by improving morphological, physiological and biochemical activity

    Directory of Open Access Journals (Sweden)

    Muhammad Iqbal

    2018-03-01

    Full Text Available The experimental work presented in this study was carried out with the hypothesis that plant derived smoke enhanced the morphological, physiological and biochemical attributes of a cereal crop, wheat (Triticum aestivum L.. Furthermore, this study supported the hypothesis that plant derived smoke acts as vegetative growth promoter, inexpensive, rapid and most appropriate eco-friendly bio-fertilizer for sustainable agriculture. Plant derived smoke was generated by burning of plant material (leaf, straws etc in a specially designed furnace, and seeds were treated with this smoke for different time duration. Four level of plant derived smoke (1 h, 2 h, 3 h and 4 h along with control were tested on four wheat cultivars in CRD repeated pot experiment. The smoke-related treatments modified number of morphological, physiological and biochemical features of wheat. Compared with the control, aerosol smoke treatment of the seeds significantly improved root length (2.6%, shoot length (7.7%, RFW (0.04%, SFW (0.7%, SDW (0.1% and leaf area (63.9%. All the smoke-related treatments significantly promoted RWC (17.3%, water potential (1.5%, osmotic potential (1.4% and MSI (14.6% whereas a pronounced increase in chlorophyll a (24.9%, chlorophyll b (21.7% and total chlorophyll contents (15.5% were recorded in response to aerosol-smoke treatments. Plant derived smoke exposure applied for short time i.e. 1 h & 2 h induced significant results as compared to prolonged PDS exposure (3 h and 4 h. The best results were observed in Pak-13 and Glaxy-13 wheat cultivars. These findings indicated that the plant-derived smoke treatment has a great potential to improve morphological, physiological and biochemical features of wheat crop.

  12. Iranian EFL Learners' Emotional Intelligence, Learning Styles, Strategy Use, and Their L2 Achievement

    Science.gov (United States)

    Afshar, Hassan Soodmand; Tofighi, Somayyeh; Hamazavi, Raouf

    2016-01-01

    The idea that language learning is facilitated or inhibited by a multitude of factors has prompted scholars in the field to investigate variables considered to be crucial in the process of second or foreign language learning. This study investigated relationships between emotional intelligence, learning style, language learning strategy use, and…

  13. Synthesis, growth, morphology of the semiorganic nonlinear optical crystal L-glutamic acid hydrochloride and its structural, thermal and SHG characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Dhanasekaran, P.; Srinivasan, K. [Crystal Growth Laboratory, Department of Physics, School of Physical Sciences, Bharathiar University, Coimbatore-641 046, Tamil Nadu (India)

    2012-12-15

    One of the halide derivatives of L-glutamic acid which was identified as a semiorganic nonlinear optical material, L-glutamic acid hydrochloride [HOOC(CH{sub 2}){sub 2}CH(NH{sub 2})COOH.HCl], was grown as bulk single crystal and its significant properties were characterized. The stoichiometric title compound was synthesized and the solubility of its recrystallized form in DD water was determined in the temperature range 30-80 C by gravimetric method. Structural confirmation was carried out by powder X-ray diffraction study through lattice parameter verification. Optical quality smaller dimension single crystals were grown from aqueous solution by self nucleation through slow evaporation of solvent method and a large dimension single crystal was grown by slow cooling method with reversible seed rotation technique. Morphological importances of different growth facets of the as grown crystals were studied through optical goniometry. Unit cell structure of the grown crystal was refined by single crystal X-ray diffraction analysis, functional groups present in the crystal responsible for various modes of vibrations were confirmed by FTIR spectroscopy analysis, thermal stability of the grown crystal was analysed by TG/DTA and DSC and second harmonic generation (SHG) of a fundamental Nd:YAG laser beam by Kurtz technique. Results indicate that the grown crystal is in stoichiometric composition and has significant improvement in its thermal and SHG properties when compared to pure L-glutamic acid polymorphs. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Low genetic differentiation among morphologically distinct ...

    African Journals Online (AJOL)

    Labeobarbus altianalis and L. bynni bynni are hexaploid cyprinid fishes in the genus Labeobarbus. In the Great Lakes region of Africa, these two large-bodied barbs exhibit considerable morphological variations. Their intraspecific classification, currently based on geographical distribution and morphological variation, is of ...

  15. An Investigation of How the Channel of Input and Access to Test Questions Affect L2 Listening Test Performance

    Science.gov (United States)

    Wagner, Elvis

    2013-01-01

    The use of video technology has become widespread in the teaching and testing of second-language (L2) listening, yet research into how this technology affects the learning and testing process has lagged. The current study investigated how the channel of input (audiovisual vs. audio-only) used on an L2 listening test affected test-taker…

  16. Proficiency and sentence constraint effects on second language word learning.

    Science.gov (United States)

    Ma, Tengfei; Chen, Baoguo; Lu, Chunming; Dunlap, Susan

    2015-07-01

    This paper presents an experiment that investigated the effects of L2 proficiency and sentence constraint on semantic processing of unknown L2 words (pseudowords). All participants were Chinese native speakers who learned English as a second language. In the experiment, we used a whole sentence presentation paradigm with a delayed semantic relatedness judgment task. Both higher and lower-proficiency L2 learners could make use of the high-constraint sentence context to judge the meaning of novel pseudowords, and higher-proficiency L2 learners outperformed lower-proficiency L2 learners in all conditions. These results demonstrate that both L2 proficiency and sentence constraint affect subsequent word learning among second language learners. We extended L2 word learning into a sentence context, replicated the sentence constraint effects previously found among native speakers, and found proficiency effects in L2 word learning. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Functional connectivity changes in second language vocabulary learning.

    Science.gov (United States)

    Ghazi Saidi, Ladan; Perlbarg, Vincent; Marrelec, Guillaume; Pélégrini-Issac, Mélani; Benali, Habib; Ansaldo, Ana-Inés

    2013-01-01

    Functional connectivity changes in the language network (Price, 2010), and in a control network involved in second language (L2) processing (Abutalebi & Green, 2007) were examined in a group of Persian (L1) speakers learning French (L2) words. Measures of network integration that characterize the global integrative state of a network (Marrelec, Bellec et al., 2008) were gathered, in the shallow and consolidation phases of L2 vocabulary learning. Functional connectivity remained unchanged across learning phases for L1, whereas total, between- and within-network integration levels decreased as proficiency for L2 increased. The results of this study provide the first functional connectivity evidence regarding the dynamic role of the language processing and cognitive control networks in L2 learning (Abutalebi, Cappa, & Perani, 2005; Altarriba & Heredia, 2008; Leonard et al., 2011; Parker-Jones et al., 2011). Thus, increased proficiency results in a higher degree of automaticity and lower cognitive effort (Segalowitz & Hulstijn, 2005). Copyright © 2012 Elsevier Inc. All rights reserved.

  18. STUDY THE MORPHOLOGY OF ASIMINA TRILOBA (L. DUNAL FRUITS AND SEEDS OBTAINED IN THE TRANSYLVANIA REGION OF ROMANIA

    Directory of Open Access Journals (Sweden)

    Beatrice Agneta Szilagyi

    2016-07-01

    Full Text Available The fruit tree Asimina triloba (L. Dunal originates in the temperate zones of North America. Its fruits are edible and have great nutritional value. The fruits' commercial potential contributes to a growing demand for information about this plant in Romania. A series of morphological observations were performed on the fruits and seeds of Asimina plants adapted to the temperate climate of the Transylvania zone of Romania.

  19. Investigation of spinal cerebrospinal fluid-contacting neurons expressing PKD2L1: evidence for a conserved system from fish to primates

    Science.gov (United States)

    Djenoune, Lydia; Khabou, Hanen; Joubert, Fanny; Quan, Feng B.; Nunes Figueiredo, Sophie; Bodineau, Laurence; Del Bene, Filippo; Burcklé, Céline; Tostivint, Hervé; Wyart, Claire

    2014-01-01

    Over 90 years ago, Kolmer and Agduhr identified spinal cerebrospinal fluid-contacting neurons (CSF-cNs) based on their morphology and location within the spinal cord. In more than 200 vertebrate species, they observed ciliated neurons around the central canal that extended a brush of microvilli into the cerebrospinal fluid (CSF). Although their morphology is suggestive of a primitive sensory cell, their function within the vertebrate spinal cord remains unknown. The identification of specific molecular markers for these neurons in vertebrates would benefit the investigation of their physiological roles. PKD2L1, a transient receptor potential channel that could play a role as a sensory receptor, has been found in cells contacting the central canal in mouse. In this study, we demonstrate that PKD2L1 is a specific marker for CSF-cNs in the spinal cord of mouse (Mus musculus), macaque (Macaca fascicularis) and zebrafish (Danio rerio). In these species, the somata of spinal PKD2L1+ CSF-cNs were located below or within the ependymal layer and extended an apical bulbous extension into the central canal. We found GABAergic PKD2L1-expressing CSF-cNs in all three species. We took advantage of the zebrafish embryo for its transparency and rapid development to identify the progenitor domains from which pkd2l1+ CSF-cNs originate. pkd2l1+ CSF-cNs were all GABAergic and organized in two rows—one ventral and one dorsal to the central canal. Their location and marker expression is consistent with previously described Kolmer–Agduhr cells. Accordingly, pkd2l1+ CSF-cNs were derived from the progenitor domains p3 and pMN defined by the expression of nkx2.2a and olig2 transcription factors, respectively. Altogether our results suggest that a system of CSF-cNs expressing the PKD2L1 channel is conserved in the spinal cord across bony vertebrate species. PMID:24834029

  20. Investigation of spinal cerebrospinal fluid-contacting neurons expressing PKD2L1: evidence for a conserved system from fish to primates

    Directory of Open Access Journals (Sweden)

    Lydia eDjenoune

    2014-05-01

    Full Text Available Over ninety years ago, Kolmer and Agduhr identified spinal cerebrospinal fluid-contacting neurons (CSF-cNs based on their morphology and location within the spinal cord. In more than two hundred vertebrate species, they observed ciliated neurons around the central canal that extended a brush of microvilli into the cerebrospinal fluid (CSF. Although their morphology is suggestive of a primitive sensory cell, their function within the vertebrate spinal cord remains unknown. The identification of specific molecular markers for these neurons in vertebrates would benefit the investigation of their physiological roles. PKD2L1, a transient receptor potential channel that could play a role as a sensory receptor, has been found in cells contacting the central canal in mouse. In this study, we demonstrate that PKD2L1 is a specific marker for CSF-cNs in the spinal cord of mouse (Mus musculus, macaque (Macaca fascicularis and zebrafish (Danio rerio. In these species, the somata of spinal PKD2L1+ CSF-cNs were located below or within the ependymal layer and extended an apical bulbous extension into the central canal. We found GABAergic PKD2L1-expressing CSF-cNs in all three species. We took advantage of the zebrafish embryo for its transparency and rapid development to identify the progenitor domains from which pkd2l1+ CSF-cNs originate. pkd2l1+ CSF-cNs were all GABAergic and organized in two rows—one ventral and one dorsal to the central canal. Their location and marker expression is consistent with previously described Kolmer-Agduhr cells. Accordingly, pkd2l1+ CSF-cNs were derived from the progenitor domains p3 and pMN defined by the expression of nkx2.2a and olig2 transcription factors, respectively. Altogether our results suggest that a system of CSF-cNs expressing the PKD2L1 channel is conserved in the spinal cord across bony vertebrate species.

  1. Linking the morphological and metabolomic response of Lactuca sativa L exposed to emerging contaminants using GC × GC-MS and chemometric tools.

    Science.gov (United States)

    Hurtado, Carlos; Parastar, Hadi; Matamoros, Víctor; Piña, Benjamín; Tauler, Romà; Bayona, Josep M

    2017-07-26

    The occurrence of contaminants of emerging concern (CECs) in irrigation waters (up to low μg L -1 ) and irrigated crops (ng g -1 in dry weight) has been reported, but the linkage between plant morphological changes and plant metabolomic response has not yet been addressed. In this study, a non-targeted metabolomic analysis was performed on lettuce (Lactuca sativa L) exposed to 11 CECs (pharmaceuticals, personal care products, anticorrosive agents and surfactants) by irrigation. The plants were watered with different CEC concentrations (0-50 µg L -1 ) for 34 days under controlled conditions and then harvested, extracted, derivatised and analysed by comprehensive two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer (GC × GC-TOFMS). The resulting raw data were analysed using multivariate curve resolution (MCR) and partial least squares (PLS) methods. The metabolic response indicates that exposure to CECs at environmentally relevant concentrations (0.05 µg L -1 ) can cause significant metabolic alterations in plants (carbohydrate metabolism, the citric acid cycle, pentose phosphate pathway and glutathione pathway) linked to changes in morphological parameters (leaf height, stem width) and chlorophyll content.

  2. Control surface morphology, structural and optical properties of Cu2O nanocrystals by using the hydrothermal technique

    Science.gov (United States)

    Gowd, A. Viswanath; Thangavel, R.

    2018-05-01

    The Cuprous oxide (Cu2O) is a reddish-brown colored p-type semiconductor compound. The Cu2O nanocrystals were successfully synthesized by using copper (II) chloride as a precursor, Sodium hydroxide as mineralizing agent with the ascorbic through hydrothermal method. The process was accomplished with 0.05 and 0.1 mol/L concentration of CuCl2.2H2O at 75°C temperature in the presence of de-ionized (DI) water. X-ray diffraction patterns of the synthesized samples powder confirmed presence of Cu2O and Cu nanoparticles due to complete and incomplete oxidation of Cu particles, respectively. The prepared nanoparticles with an average size of below 40 nm were estimated using Debye - Scherrer method and the analysis shown that an increase in CuCl2.2H2O concentration from 0.05 to 0.1M leads to the downsizing of the Cu2O particles. Field - emission scanning electron microscopy data showed that the morphology has changed from nano - cubes to octahedron by increasing the precursor mole concentration. Optical measurements show the bandgap shift towards higher energy with changing morphology to nano-cubes and octahedron. The luminescence peaks at 450 and 464 nm shows the presence of Cu2O phase and remaining peaks were due to Cu phase and interstials defects.

  3. Effects of elevated carbon dioxide concentrations on some morphological and physiological characteristics of sesame (Sesamum indicum L. and amaranthus (Amaranthus retroflexus L.

    Directory of Open Access Journals (Sweden)

    M. Goldani

    2016-05-01

    Full Text Available Carbon dioxide is the most important resource for crop growth. In order to investigate the effect of elevated CO2 concentration on morphological and physiological characteristics of sesame (Sesamum indicum L. and amaranthus (Amaranthus retroflexus L. an experiment was conducted in greenhouse conditions. The experiment was factorial based on randomized complete block design with six treatments and three replications. Different CO2 concentrations (including 360, 520 and 750 ppm on monoculture and mixture of two species were investigated. The results indicated that plant height, node number, internode and stem dry weight had significant differences in the CO2 concentrations. Elevated CO2 concentration caused increasing plant height, node number, internode and stem dry weight in sesame and monoculture was better than mixtures, but in the amaranthus, elevated CO2 concentration resulted is decreasing plant height, node number, and internode and stem dry weight. Number and length of branches and their dry weight had significant different in CO2 concentrations. So, effect of elevated CO2 concentration was positive for sesame and negative for amaranthus. In amaranthus, monoculture was more successful than mixture. In the sesame, yield was included number and weight capsule and in the amaranthus was included total seed weight, that both had significant affected. Elevated CO2 concentration had positive effect on yield of sesame and negative effect on yield of amaranthus. In the sesame, monoculture was more successful. The effect of elevated CO2 concentration was significant on transpiration and photosynthesis rates. In the sesame, elevated CO2 concentration increased transpiration and photosynthesis rates and decreased them in the amaranthus. In the sesame, shoot total length and root dry weight was significantly different in CO2 concentrations and increased by elevated CO2 concentration, but in the amaranthus, decreased by elevated CO2 concentration

  4. Morphologic alterations on red blood cells labeled with technetium-99m: the effect of Mentha crispa L. (hortela) extract

    International Nuclear Information System (INIS)

    Santos-Filho, S.D.; Dire, G.L.; Lima, E.; Pereira, M.; Bernardo-Filho, M.

    2002-01-01

    The use of natural products, as medicinal plants, is very frequent in the world. Mentha crispa L. (M. crispa) is utilized in herbal medicine. Blood elements labeled with technetium-99m (99mTc) are used in nuclear medicine procedures and this labeling process may be altered by drugs. We have investigated the possibility of M. crispa extract being capable to alter the labeling of blood elements with 99mTc. Blood was incubated with M. crispa extract in various concentrations (6.25, 12.5, 25, 50 and 100%). Stannous chloride solution and Tc-99m, as sodium pertechnetate, were added. Blood was centrifuged and plasma (P) and blood cells (BC) were isolated. Samples of P and BC were also precipitated, centrifuged and insoluble (IF) and soluble (SF) separated. The percentage of radioactivity (%ATI) in BC, IF-P and IF-BC was calculated. Histological evaluations of the red blood cells (RBC) were performed with blood samples treated with various concentrations of M. Crispa L. and the morphology of the RBC was observed under optical microscope. Important morphological alterations expressed by mean of the perimeter/area of the RBC treated with M. crispa: 6.25% (0.67 ± 0.02), 12.5% (0.77 ± 0.03), 25% (0.73 ± 0.04), 50% (0.76 ± 0.04), 100% (0.69 ± 0.08) and the control cells (0.67 ± 0.05). The %ATI decreased: (i) on BC from 97.3 ± 1.92 to 60.0 ± 2.44; (ii) on IF-P from 74.8 ± 3.78 to 9.99 ± 3.61; (iii) on IF-BC from 88.6 ± 5.41 to 58.4 ± 11.55. The perimeter/area of the RBC showed significant differences (P>0.01) when compared 6.25% and 12.5%, and when compared 6.25% and 50% of M. Crispa L. extract. These findings could also justify the decrease of the labeling of BC with 99mTc in presence of M. Crispa extract

  5. The Effects of L2 Experience on L3 Perception

    Science.gov (United States)

    Onishi, Hiromi

    2016-01-01

    This study examines the influence of experience with a second language (L2) on the perception of phonological contrasts in a third language (L3). This study contributes to L3 phonology by examining the influence of L2 phonological perception abilities on the perception of an L3 at the beginner level. Participants were native speakers of Korean…

  6. Structural, morphological and optical investigations on electron-beam irradiated PbF2-TeO2-B2O3-Eu2O3 glasses

    Science.gov (United States)

    Wagh, Akshatha; Petwal, Vikash; Dwivedi, Jishnu; Upadhyaya, V.; Raviprakash, Y.; Kamath, Sudha D.

    2016-09-01

    Combined structural, optical and morphological studies were carried out on Eu2O3 doped PbF2-TeO2-B2O3 glass samples, before and after being subjected to electron beam of energy 7.5 MeV. XRD confirmed the amorphous nature of the glasses even after 150 kGy electron beam irradiation. Densities of the irradiated samples showed slightly greater values when compared to their respective values before irradiation, which proved the increase in the compaction of the network. The intensities of the three prominent bands; B-O-B linkages, BO4 units and BO3 units of FT-IR spectra, of the titled glasses, showed slight decrease after electron beam irradiation. The decrement in the values of energy band gap and shift in cut-off wavelength towards red edge, proved the formation of color centers in the glass network after irradiation. The change in Hunter L values, through color measurement was a proof for the Farbe/color/absorption centers created in the glass sites after irradiation.

  7. Reassembling Formal Features in Articles by L1 Persian Learners of L2 English

    Directory of Open Access Journals (Sweden)

    Marjansadat Momenzadeh

    2015-08-01

    Full Text Available There has been considerable debate over what the sources of morphological variation in second language acquisition are. From among various hypotheses put forth on the topic, the feature reassembly hypothesis (Lardiere, 2005 assumes that it is the reconfiguration of features in the L2 which causes variation between the performance of natives and non-natives. Acknowledged as one of the most difficult elements of English grammar to be acquired by learners, the article system was the focus of the present study which aimed at attending to the acquisition of that system by Persian learners. This descriptive piece of research focused on how the article system functions in English and Persian, the similarities found across the two languages and the possible sources of difficulty for Persian learners in using English articles as related to their L1. The participants included Persian learners at three levels of grammatical knowledge. A group of English native speakers also took part in the study. A grammaticality judgment test and a translation test were conducted to collect data. Comparisons were made among the four groups, using ANOVAs. Based on the results, it is argued that the observed pattern of article use among Persian speaking learners can be best accounted for by the feature reassembly hypothesis.

  8. Cryopreservation of coconut (Cocos nucifera L.) zygotic embryos does not induce morphological, cytological or molecular changes in recovered seedlings.

    Science.gov (United States)

    Sisunandar; Rival, Alain; Turquay, Patricia; Samosir, Yohannes; Adkins, Steve W

    2010-07-01

    The present study aimed at exploring the fidelity of coconut (Cocos nucifera L.) plants recovered from cryopreservation. Zygotic embryos from various different cultivars were cryopreserved following four successive steps, namely: rapid dehydration, rapid freezing, rapid thawing and in vitro recovery followed by acclimatization. At the end of the acclimatization period, the seedlings were compared to counterparts of the same age, which were produced from non-cryopreserved embryos. Both series were submitted to morphological, cytological and molecular comparisons. No significant differences in terms of growth rates could be measured. In addition, no morphological variation could be detected through the measurement of shoot elongation rates, production of opened leaves, and the number and total length of primary roots. Karyotype analysis revealed the same chromosome number (2n = 32) in all studied cultivars independently of cryopreservation. No significant differences could be observed between control and cryopreserved material concerning the type of chromosomes, the length of the long and short arms, the arm length ratio and the centromeric index. However, idiogram analysis did show a greater number of black banding on chromosomes isolated from cryopreserved material. Genetic and epigenetic fidelity was assessed through microsatellite (SSR) analysis and global DNA methylation rates; no significant differences would be observed between genomic DNAs isolated from seedlings originating from cryopreserved embryos and respective controls. In conclusion, our results suggest that the method of cryopreservation under study did not induce gross morphological, genetic or epigenetic changes, thus suggesting that it is an appropriate method to efficiently preserve coconut germplasm.

  9. Opinion mining on book review using CNN-L2-SVM algorithm

    Science.gov (United States)

    Rozi, M. F.; Mukhlash, I.; Soetrisno; Kimura, M.

    2018-03-01

    Review of a product can represent quality of a product itself. An extraction to that review can be used to know sentiment of that opinion. Process to extract useful information of user review is called Opinion Mining. Review extraction model that is enhancing nowadays is Deep Learning model. This Model has been used by many researchers to obtain excellent performance on Natural Language Processing. In this research, one of deep learning model, Convolutional Neural Network (CNN) is used for feature extraction and L2 Support Vector Machine (SVM) as classifier. These methods are implemented to know the sentiment of book review data. The result of this method shows state-of-the art performance in 83.23% for training phase and 64.6% for testing phase.

  10. Morphological identification of Lucilia sericata, Lucilia cuprina and their hybrids (Diptera, Calliphoridae)

    Science.gov (United States)

    Williams, Kirstin A.; Villet, Martin H.

    2014-01-01

    Abstract Hybrids of Lucilia sericata and Lucilia cuprina have been shown to exist in previous studies using molecular methods, but no study has shown explicitly that these hybrids can be identified morphologically. Published morphological characters used to identify L. sericata and L. cuprina were reviewed, and then scored and tested using specimens of both species and known hybrids. Ordination by multi-dimensional scaling indicated that the species were separable, and that hybrids resembled L. cuprina, whatever their origin. Discriminant function analysis of the characters successfully separated the specimens into three unambiguous groups – L. sericata, L. cuprina and hybrids. The hybrids were morphologically similar irrespective of whether they were from an ancient introgressed lineage or more modern. This is the first evidence that hybrids of these two species can be identified from their morphology. The usefulness of the morphological characters is also discussed and photographs of several characters are included to facilitate their assessment. PMID:25061373

  11. Emergent learning and learning ecologies in Web 2.0

    OpenAIRE

    Williams, Roy; Karousou, Regina; Mackness, J.

    2011-01-01

    This paper describes emergent learning and situates it within learning networks and systems and the broader learning ecology of Web 2.0. It describes the nature of emergence and emergent learning and the conditions that enable emergent, self-organised learning to occur and to flourish. Specifically, it explores whether emergent learning can be validated and self-correcting and whether it is possible to link or integrate emergent and prescribed learning. It draws on complexity theory, commu...

  12. Pengembangan problem based learning dengan assessment for learning berbantuan smartphone dalam pembelajaran matematika

    Directory of Open Access Journals (Sweden)

    Muhammad Ridlo Yuwono

    2017-11-01

    Full Text Available [Bahasa]: Penelitian ini bertujuan untuk menghasilkan model Problem Based Learning (PBL menggunakan penilaian Assessment for Learning (AfL berbantuan smartphone, disingkat PBL-AfL-S yang valid, praktis dan efektif untuk mendukung implementasi kurikulum 2013 di SMA. Tahap-tahap pengembangan model PBL-AfL-S terdiri dari penelitian pendahuluan, pengembangan/prototiping, dan evaluasi. Kualitas model PBL-AfL-S mengacu pada kriteria kualitas menurut Nieveen (1999 yaitu valid, praktis, dan efektif. Model PBL-AfL-S diujicobakan di SMA Negeri 3 Klaten dalam dua tahap uji coba. Uji coba tahap I dilaksanakan di kelas XI-IPA 6 dan uji coba tahap II dilaksanakan di kelas XI-IPA 7. Instrumen penelitian terdiri dari: 1 Instrumen penilaian kevalidan komponen model dan perangkat pendukung pembelajaran, 2 Instrumen kepraktisan aktivitas guru dan siswa, dan 3 Instrumen keefektifan yang meliputi angket penilaian diri, lembar penilaian proyek, tes prestasi belajar, dan lembar respon siswa. Hasil penelitian menunjukkan bahwa model PBL-AfL-S dan perangkat pembelajarannya telah memenuhi kriteria valid, praktis dan efektif. Kata kunci: Pembelajaran; Masalah; Asesmen; Smartphone [English]: This study aims to develop a Problem Based Learning (PBL model using Assessment for Learning (AFL with smartphone, abbreviated as PBL-AfL-S as valid, practical and effective to support the implementation of the 2013 curriculum in High School. The stages of developing the PBL-AfL-S model consist of preliminary research, development or prototyping, and evaluation. The quality criteria of PBL-AfL-S refer to Nieveen (1999, i.e. valid, practical, and effective. The PBL-AfL-S model was piloted in SMA Negeri 3 Klaten in two phases. Tryout 1 was conducted in class XI-IPA 6 and tryout 2 was in class XI-IPA 7. The research instruments consist of: 1 The validity instrument of the model and its learning support tools, 2 the practicality of the teacher’s and students’ activity, and 3 The

  13. Investigation of the operating conditions to morphology evolution of β-L-glutamic acid during seeded cooling crystallization

    Science.gov (United States)

    Zhang, Fangkun; Liu, Tao; Huo, Yan; Guan, Runduo; Wang, Xue Z.

    2017-07-01

    In this paper the effects of operating conditions including cooling rate, initial supersaturation, and seeding temperature were investigated on the morphology evolution of β-L-glutamic acid (β-LGA) during seeded cooling crystallization. Based on the results of in-situ image acquisition of the crystal morphology evolution during the crystallization process, it was found that the crystal products tend to be plate-like or short rod-like under a slow cooling rate, low initial supersaturation, and low seeding temperature. In the opposite, the operating conditions of a faster cooling rate, higher initial supersaturation, and higher seeding temperature tend to produce long rod-like or needle-like crystals, and meanwhile, the length and width of crystal products will be increased together with a wider crystal size distribution (CSD). The aspect ratio of crystals, defined by the crystal length over width measured from in-situ or sample images, was taken as a shape index to analyze the crystal morphologies. Based on comparative analysis of the experimental results, guidelines on these operating conditions were given for obtaining the desired crystal shapes, along with the strategies for obtaining a narrower CSD for better product quality. Experimental verifications were performed to illustrate the proposed guidelines on the operating conditions for seeded cooling crystallization of LGA solution.

  14. ERPs recorded during early second language exposure predict syntactic learning.

    Science.gov (United States)

    Batterink, Laura; Neville, Helen J

    2014-09-01

    Millions of adults worldwide are faced with the task of learning a second language (L2). Understanding the neural mechanisms that support this learning process is an important area of scientific inquiry. However, most previous studies on the neural mechanisms underlying L2 acquisition have focused on characterizing the results of learning, relying upon end-state outcome measures in which learning is assessed after it has occurred, rather than on the learning process itself. In this study, we adopted a novel and more direct approach to investigate neural mechanisms engaged during L2 learning, in which we recorded ERPs from beginning adult learners as they were exposed to an unfamiliar L2 for the first time. Learners' proficiency in the L2 was then assessed behaviorally using a grammaticality judgment task, and ERP data acquired during initial L2 exposure were sorted as a function of performance on this task. High-proficiency learners showed a larger N100 effect to open-class content words compared with closed-class function words, whereas low-proficiency learners did not show a significant N100 difference between open- and closed-class words. In contrast, amplitude of the N400 word category effect correlated with learners' L2 comprehension, rather than predicting syntactic learning. Taken together, these results indicate that learners who spontaneously direct greater attention to open- rather than closed-class words when processing L2 input show better syntactic learning, suggesting a link between selective attention to open-class content words and acquisition of basic morphosyntactic rules. These findings highlight the importance of selective attention mechanisms for L2 acquisition.

  15. Theory of endogenous and exogenous motivation in L2 migration

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    Kambon, Obadele Bakari

    2015-09-01

    Full Text Available Implied in theories of Second Language Acquisition (SLA is the notion that language learning is analogous to obtaining or acquiring a possession – thus the use of the term ‘acquisition.’ While this interpretation has gone relatively unchallenged in the literature, this article introduces a new analogy whereby language learning is seen as analogous to a process of permanent or semi-permanent migration towards a new socio-linguistic L2 space. As such, a theory of endogenous and exogenous motivation is delineated, entailing a dynamic interplay between internal (primarily psychological and external (primarily sociological push-pull factors. Endogenous and exogenous push-pull factors, together with various other personal factors, contribute to learner decisions to migrate towards, move away from or remain inert with regard to the target language. Further, motivation is framed in the larger theoretical context of causation.

  16. L2 Learners’ Proficiency Development through Noticing Feedback

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    Seyed Saber Alavi

    2015-10-01

    Full Text Available This experimental study investigated the relationship between noticing of corrective feedback and L2 development considering the learners’ perspective on error correction. Specifically, it aimed to uncover the noticeability and effectiveness of recasts, prompts, a combination of the two, to determine a relationship between noticing of CF and learning of the past tense. The participants were four groups of college ESL learners (n = 40. Each group was assigned to a treatment condition, but the researcher taught the control group. CF was provided to learners in response to their mistakes in forming the past tense. While noticing of CF was assessed through immediate recall and questionnaire responses, learning outcomes were measured through picture description administered via pre-test, post-test, and delayed post-test design. Learner beliefs about CF were probed by means of a 40-item questionnaire. The results indicated that the noticeability of CF is dependent on the grammatical target it addresses and that the feedback techniques that push learners to self-correct alone or in combination with target exemplars are more effective in. In relation to the learning outcomes, the overall past tense accuracy increased more than that for questions, but there were no significant differences between the groups. Finally, in relation to the beliefs about CF, the participants’ responses centered on the importance of oral CF, recasts as CF technique, prompts as CF technique, and affective consequences of CF, two of which mediated the noticeability of the supplied CF, but none impacted the learning outcomes.

  17. The Inseparability of Cognition and Emotion in Second Language Learning

    Science.gov (United States)

    Swain, Merrill

    2013-01-01

    The scholarly literature about the process of second language (L2) learning has focused to a considerable extent on cognitive processes. Left aside are questions about how emotions fit into an understanding of L2 learning. One goal of this plenary is to demonstrate that we have limited our understanding of L2 learning by failing to take into…

  18. A descriptor list of Silybum marianum (L. Gaertner – morphological and biological characters

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    Dušková, Elena

    2016-07-01

    Full Text Available Silybum marianum (L. Gaertn (Milk thistle is an important medicinal plant which fruits are used for treatment of various liver diseases. In an effort to utilize the genetic potential of cultivated plants in the best way, the breeding of new high-performance cultivars is underway all over the world. Genetic improvement in Silybum can only be, as with all other plants, achieved through a clear understanding of the plant´s behaviour and the amount of variability presented in wild populations. Surprisingly no descriptor list has been compiled up to now, which would permit an objective and easily repeatable description an evaluation of the different Silybum genotypes. The first part of such a descriptor list, which is intended mainly for evaluation of genotypes perspective for fruit production, is presented here and it contains both the morphological and biological characters.

  19. Does the Medium Really Matter in L2 Development? The Validity of Call Research Designs

    Science.gov (United States)

    Cerezo, Luis; Baralt, Melissa; Suh, Bo-Ram; Leow, Ronald P.

    2014-01-01

    Currently, an increasing number of educational institutions are redefining second/foreign language (L2) classrooms by enhancing--or even replacing--traditional face-to-face (FTF) instruction with computer-assisted language learning (CALL). However, are these curricular decisions supported by research? Overall, a cursory review of empirical studies…

  20. À la recherche de la morphologie silencieuse : sur le développement du pluriel en francais L2 écrit

    OpenAIRE

    Ågren, Malin

    2008-01-01

    This dissertation deals with the morphological development in written L2 French by Swedish learners. The thesis presents a detailed analysis of number marking and agreement in NPs and VPs, focusing mainly on the production of the morphemes –s (in NP) and the third person plural –nt (in VP). These agreements are particularly interesting in French where number morphology is often silent in the oral language and thus potentially difficult to produce in writing. The aim of the thesis is to d...

  1. The Concept of L2 User and the goals of Second Language Learning

    OpenAIRE

    Juanggo, Willy

    2017-01-01

    It is generally considered that knowing one language is not enough in this era. People need to learn a second language in addition to their mother tongue to meet the demand of today’s life as many of them are becoming a part of multilingual society as well as to face the globalisation. This paper aims to demonstrate the reasons of people learning a second by looking at the several goals they want to achieve in current situation and link it to the second language learning in education context....

  2. Dendritic spine morphology and dynamics in health and disease

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    Lee S

    2015-06-01

    Full Text Available Stacey Lee,1 Huaye Zhang,2 Donna J Webb1,3,4 1Department of Biological Sciences, Vanderbilt University, Nashville, TN, 2Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 3Department of Cancer Biology, 4Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN, USA Abstract: Dendritic spines are actin-rich structures that form the postsynaptic terminals of excitatory synapses in the brain. The development and plasticity of spines are essential for cognitive processes, such as learning and memory, and defects in their density, morphology, and size underlie a number of neurological disorders. In this review, we discuss the contribution and regulation of the actin cytoskeleton in spine formation and plasticity as well as learning and memory. We also highlight the role of key receptors and intracellular signaling pathways in modulating the development and morphology of spines and cognitive function. Moreover, we provide insight into spine/synapse defects associated with several neurological disorders and the molecular mechanisms that underlie these spine defects. Keywords: dendritic spines, synapses, synaptic plasticity, actin cytoskeleton, glutamate receptors, neurological disorders

  3. The effects of captioning texts and caption ordering on L2 listening comprehension and vocabulary learning

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    Fatemeh Alikhani

    2013-07-01

    Full Text Available This study investigated the effects of captioned texts on second/foreign (L2 listening comprehension and vocabulary gains using a computer multimedia program. Additionally, it explored the caption ordering effect (i.e. captions displayed during the first or second listening, and the interaction of captioning order with the L2 proficiency level of language learners in listening comprehension and vocabulary performance. To these ends, a computer software program was designed and 200 EFL learners (100 high-intermediate and 100 low-intermediate level students were asked to participate in the experiment. They were randomly assigned into four groups: captioned (listening to texts twice with captions, noncaptioned (listening to texts twice without captions, first captioned (listening to texts first with captions and then without captions, and second captioned (listening to texts first without captions and then with captions groups. They listened to four audio texts (i.e. short stories twice and took the listening and vocabulary tests, administered through the software. Results from t-tests and two-way ANOVAs showed that the captioned stories were more effective than the non-captioned ones. Moreover, the caption ordering had no significant effect on the participants' L2 listening comprehension and vocabulary performance. Finally, L2 proficiency level differences did not affect performance derived from caption ordering.

  4. An investigation into the relationship among EFL teachers’ reflection, classroom management orientations, and perceptions of language learning strategies and students’ L2 achievement

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    Mohammad Hadi Mahmoodi

    2015-08-01

    Full Text Available The  present  study  was  conducted  to  investigate  the  relationship  among  three  important  teacher variables and students’ L2 achievement. To this end, 105 high school EFL teachers from Shiraz and Hamadan were asked to fill out three sets of instruments: the reflective teaching instrument, (Akbari, Behzadpour  &  Dadvand,  2010,  the  Attitudes  and  Beliefs  on  Classroom  Control  Inventory  (Martin, Yin,  &  Baldwin,  1998,  and  the  Strategy  Inventory  for  Language  Learning  (Ardasheva  &  Tretter, 2013.  Also,  the  scores  of  the  English  final  exams  of  2673  third-grade  high  school  students  were collected. The  results  of  Pearson  Product  Moment  Correlations  revealed  that  there  was  a  significant correlation  between  the  above-mentioned  three  teachers’  variables  and  their  students’  L2 achievement.  The  results  also  showed  a  significant  difference  between  male  and  female  teachers  in the  degree  of  perceptions  of  LLSs,  while  no  significant  differences  were  found  between  the  two genders  regarding  their  classroom  management  orientations  and  reflection.  Moreover,  running multiple  regression  analysis,  it  was  revealed  that  among  the teachers’ variables, reflection was  the strongest  predicator  of  students’ L2 achievement. Finally, based on the results of this study, some practical implications for maximizing students’ L2 achievement in English language classrooms are presented.

  5. Poly(2-aminothiazole)-silica nanocomposite particles: Synthesis and morphology control

    Science.gov (United States)

    Zou, Hua; Wu, Di; Sun, Hao; Chen, Suwu; Wang, Xia

    2018-04-01

    Synthesis of conducting polymer-silica colloidal nanocomposites has been recognized as an effective method to overcome the poor processability of heterocyclic conducting polymers prepared by chemical oxidative method. However, the morphology control of such conducting polymer-silica nanocomposites was seldomly reported in the literature. Novel poly(2-aminothiazole)(PAT)-silica nanocomposite particles can be conveniently prepared by chemical oxidative polymerization of 2-aminothiazole using CuCl2 oxidant in the presence of ∼20 nm silica nanoparticles. The effects of varying the oxidant/monomer ratio and silica sol concentration on the morphology and size of the resulting PAT-silica nanocmposites have been studied. Optimization of the oxidant/monomer molar ratio and initial silica sol concentration allows relatively round spherical particles of 150-350 nm in diameter to be achieved. The nanocomposite particles have a well-defined raspberry-like morphology with a silica-rich surface, but a significant fraction of PAT component still exists on the surface and, which is beneficial for its applications. Furthermore, the surface compositions of the colloidal nanocomposites could be regulated to some extent. Based on the above results, a possible formation mechanism of the spherical nanocomposite particles is proposed.

  6. Morphological features of different polyploids for adaptation and molecular characterization of CC-NBS-LRR and LEA gene families in Agave L.

    Science.gov (United States)

    Tamayo-Ordóñez, M C; Rodriguez-Zapata, L C; Narváez-Zapata, J A; Tamayo-Ordóñez, Y J; Ayil-Gutiérrez, B A; Barredo-Pool, F; Sánchez-Teyer, L F

    2016-05-20

    Polyploidy has been widely described in many Agave L. species, but its influence on environmental response to stress is still unknown. With the objective of knowing the morphological adaptations and regulation responses of genes related to biotic (LEA) and abiotic (NBS-LRR) stress in species of Agave with different levels of ploidy, and how these factors contribute to major response of Agave against environmental stresses, we analyzed 16 morphological trials on five accessions of three species (Agave tequilana Weber, Agave angustifolia Haw. and Agave fourcroydes Lem.) with different ploidy levels (2n=2x=60 2n=3x=90, 2n=5x=150, 2n=6x=180) and evaluated the expression of NBS-LRR and LEA genes regulated by biotic and abiotic stress. It was possible to associate some morphological traits (spines, nuclei, and stomata) to ploidy level. The genetic characterization of stress-related genes NBS-LRR induced by pathogenic infection and LEA by heat or saline stresses indicated that amino acid sequence analysis in these genes showed more substitutions in higher ploidy level accessions of A. fourcroydes Lem. 'Sac Ki' (2n=5x=150) and A. angustifolia Haw. 'Chelem Ki' (2n=6x=180), and a higher LEA and NBS-LRR representativeness when compared to their diploid and triploid counterparts. In all studied Agave accessions expression of LEA and NBS-LRR genes was induced by saline or heat stresses or by infection with Erwinia carotovora, respectively. The transcriptional activation was also higher in A. angustifolia Haw. 'Chelem Ki' (2n=6x=180) and A. fourcroydes 'Sac Ki' (2n=5x=150) than in their diploid and triploid counterparts, which suggests higher adaptation to stress. Finally, the diploid accession A. tequilana Weber 'Azul' showed a differentiated genetic profile relative to other Agave accessions. The differences include similar or higher genetic representativeness and transcript accumulation of LEA and NBS-LRR genes than in polyploid (2n=5x=150 and 2n=6x=180) Agave accessions

  7. IL FENOMENO DELL’ALTERNANZA L1/L2 NELL’INSEGNAMENTO DELL’ITALIANO COME LINGUA STRANIERA. ANALISI DI UN CORPUS DI INTERAZIONI DIDATTICHE

    Directory of Open Access Journals (Sweden)

    Paola Arrigoni

    2012-02-01

    Full Text Available La modalità plurilingue della comunicazione in classi di lingua straniera può rientrare tra le strategie pedagogiche a disposizione dell’insegnante per il raggiungimento di precisi scopi didattici e formativi. Partendo da una breve analisi sul significato di parlante plurilingue e plurilinguismo stesso, in questo articolo si è voluto esaminare come si attua una educazione al plurilinguismo in contesti formativi e, in particolare, se e come l’utilizzo della L1 può costituire uno strumento di supporto all’insegnamento e all’apprendimento di una lingua straniera. A questo scopo sono stati analizzati i dati raccolti presso l’Università di Coventry durante corsi di italiano L2 per studenti anglofoni. I fenomeni di contatto linguistico L1/L2 più frequenti e significativi sono stati suddivisi in base al parlante e alle loro funzioni.   The phenomena of l1/l2 alternation in the teaching of italian as a foreign language. analysis of a corpus of didactic interactions Multilingual communication in foreign language classrooms can be considered as one of the teacher’s pedagogical  strategies to achieve specific educational aims. Through a brief analysis of the meaning of multilingual speakers and multilingualism, this article examines how an education to multilingualism in teaching contexts is carried out and, in particular, if and how the use of the L1 can be a helpful tool for the foreign language teaching and learning. For this purpose the data collected at Coventry University during Italian (L2 classrooms for English students were examined. The more common and meaningful phenomena of linguistic contact between L1 and L2 were grouped according to the speaker and to their functions.

  8. LA ICLASSE – SMARTPHONE E ITALIANO L2/LS

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    Filippo Zanoli

    2012-02-01

    Full Text Available Mai come oggi le classi (di Italiano L2, ma non solo sono così fortemente colonizzate dal digitale. L’invasione si è palesata sotto forma di telefonini cellulari (smartphone e tablet dotati di connessione internet e infinite potenzialità sotto forma di applicazioni che possono sia aiutare il discente sia, se male impiegati, ostacolarlo dall’intraprendere un proficuo percorso di apprendimento. Compito dell’insegnante di lingua è circoscrivere l’influenza e l’uso di tali strumenti – che non sono mero techné, ma un modo di funzionare di una generazione – non  per vietarli ma per proporre un approccio e un loro utilizzo costruttivo quali mezzi dalle grandi potenzialità nell’apprendimento di una lingua straniera.     The 1st class – Smartphones and Italian L2/FL   Classrooms (for Italian L2, but not only have never before been so strongly digitally oriented. This invasion is made tangible by smartphones and tablets equipped with internet connections and infinite potential thanks to applications which can help students in their studies, or hinder them if used incorrectly. The language teacher’s task is to circumscribe the influence and use of these tools– which are not mere techné, but the way an entire generation functions – not to prohibit using them but to propose using them constructively, thanks to their great potential for foreign language learning.

  9. Cultural Conceptualisations in Learning English as an L2: Examples from Persian-Speaking Learners

    Science.gov (United States)

    Sharifian, Farzad

    2013-01-01

    Traditionally, many studies of second language acquisition (SLA) were based on the assumption that learning a new language mainly involves learning a set of grammatical rules, lexical items, and certain new sounds and sound combinations. However, for many second language learners, learning a second language may involve contact and interactions…

  10. The Relationship between Strategic Reading Instruction, Student Learning of L2-Based Reading Strategies and L2 Reading Achievement

    Science.gov (United States)

    Akkakoson, Songyut

    2013-01-01

    This study investigates the relationship between strategic reading instruction, the process of learning second language-based reading strategies and English reading achievement for Thai university students of science and technology. In a course in reading general English texts for 16?weeks, 82 students were taught using a strategies-based approach…

  11. The Effect of Field Dodder (Cuscuta campestris Yunck. on Morphological and Fluorescence Parameters of Giant Ragweed (Ambrosia trifida L.

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    Sava Vrbničanin

    2013-01-01

    Full Text Available The effect of the parasitic flowering plant known as field dodder (Cuscuta campestrisYunck. on morphological and fluorescence parameters of infested giant ragweed(Ambrosia trifida L. plants was examined under controlled conditions. The parameters ofchlorophyll fluorescence (Fo, Fv/Fm, ΦPSII, Fv, Fm, ETR and IF were measured on infested (Iand non-infested (N A. trifida plants over a period of seven days, beginning with the day ofinfestation. Morphological parameters (plant height, dry and fresh weight were measuredon the last day of fluorescence measurements. C. campestris was found to affect the height,fresh and dry weight of the infested A. trifida plants, causing significant reduction in plantheight and dry weight. Field dodder also affected several parameters of chlorophyll fluorescence(Fo, Fv/Fm, ΦPSII and Fv in infested A. trifida plants.

  12. MORPHOLOGICAL ANALYSIS OF THE LEAVES OF Anacardium occidentale L.

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    Glenda Quaresma Ramos

    2016-03-01

    Full Text Available In morphological studies are analyzed various parameters, ranging from macro scale through the micro scale to the nanometer scale, which contribute to the study of taxonomy, pharmacognosy, ecology, among others. Among the structures found in plants, the leaves are most organs analyzed. This study aimed to analyze morphological features of the leaves of the cashew tree, which is a plant of great commercial importance in Brazil. In this work we observed sinuous epidermal cells in the adaxial and abaxial, characterize their stomata in paracytic surrounded subsidiaries cells. On the abaxial surface the presence of glandular trichomes was observed; and cross-sectional analysis showed a single-layered epidermis with compact mesophyll and several layers of parenchyma cells. Keywords: leaf anatomy; cashew tree; optical microscopy.

  13. Bio-functionalizing of α-MnO_2 nanorods with natural L-amino acids: A favorable adsorbent for the removal of Cd(II) ions

    International Nuclear Information System (INIS)

    Mallakpour, Shadpour; Motirasoul, Forough

    2017-01-01

    α-MnO_2 nanorods were prepared by hydrothermal method and then the surface of these nanorods were covalently biofunctionalized with natural L-amino acids (alanine, phenylalanine, leucine, isoleucine, methionine, and valine). The modified α-MnO_2 nanorods were analyzed by Fourier transform infrared spectroscopy and X-ray diffraction. Morphological studies were carried out by field emission scanning electron microscopy and transmission electron microscopy. The morphology of nanorods was improved after biofunctionalization and aggregation was reduced. In addition, the thermal gravimetric analysis was used for demonstrating a successful grafting of amino acids to the surface of α-MnO_2 nanorods and determine the degree of functionalization. The amount of amino acids grafted onto α-MnO_2 surface was estimated to be 5–32 wt%. Finally, the α-MnO_2 and α-MnO_2-L-valine were investigated as adsorbents for the removal of cadmium ions from aqueous solution. The results showed that they have a potential to be used as effective adsorbents for cadmium ions removal from the aqueous solution. The equilibrium adsorption data showed the best fit for the pseudo-second-order and the Freundlich models. - Highlights: • α-MnO_2 nanorods were biofunctionalized with natural L-amino acids. • Biofunctionalized α-MnO_2 nanorods by solvothermal strategy were fully characterized. • Cadmium adsorption property of α-MnO_2 and α-MnO_2-L-valine was studied.

  14. Blogging Identity: How L2 Learners Express Themselves

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    Kiyomi FUJII

    2015-06-01

    Full Text Available This study discusses language learning and identity, particularly pertaining to intermediate-advanced-level Japanese-language learners, focusing on their target language and identity expression through their interactions with peers and Japanese college students. When learners of Japanese express their identities while interacting with others in their target language, they feel a gap between the self-image they want to present, and the image they are capable of presenting in Japanese (Siegal, 1994, 1995, 1996. Along with adjusting their L1 and L2 usage depending on their interlocutor (Kurata 2007, learners also use different sentence-ending styles depending on the role they want to assume (Cook 2008. By conducting a case study, the present inquiry attempts to address how learners of Japanese express their identities through blog conversations, focusing on their language choice and expressions. Results suggest that participants use the formal endings for self-presentation and projection of their student and classmate identity. However, when expressing emotion some students preferred informal endings, or sentence-final particles.

  15. On the attractiveness of social media for language learning: a look at the state of the art De l'attrait des médias sociaux pour l'apprentissage des langues – Regard sur l'état de l'art

    Directory of Open Access Journals (Sweden)

    Katerina Zourou

    2012-03-01

    Full Text Available This paper sets the stage for the articles selected for the special issue "Language learning and social media: (revolution?". Starting with some definitions of mainstream terms like "social media", "web 2.0", "social web", "social networking sites (SNS" and "web 2.0 language learning communities". The purpose is not to "reinvent the wheel" by suggesting new definitions, but to synthesize definitions of mainstream terms and juxtapose them to similar concepts from CALL literature. We then critically discuss three key features of web 2.0 technologies (user participation, openness and network effects. Despite the fact that these three features were present to some extent in technologies prior to social media, we examine whether they take on a radically different meaning in the social media era. Research insights are discussed in the last section of the paper.Ce texte dresse l'arrière-plan contextuel et notionnel des articles retenus pour le numéro spécial "Médias sociaux et apprentissage des langues : (révolution ?". Il commence par une définition d'un certain nombre de termes qui dominent le discours actuel comme "médias sociaux", "web 2.0", "web social", "sites de réseautage social" et "communautés web 2.0 d'apprentissage des langues". Il ne s'agit pas de "réinventer la roue" en suggérant de nouvelles définitions mais de synthétiser les définitions dominantes et de les confronter à des concepts proches de la littérature du domaine de l'Alao. Sont ensuite discutés trois aspects clés des technologies du web 2.0 (participation de l'utilisateur, ouverture et effets de réseau. Ces trois caractéristiques étaient, certes, déjà présentes avec les technologies qui ont précédé les médias sociaux, nous examinons donc en quoi elles prennent, ou non, un sens radicalement différent à l'ère des médias sociaux. Un certain nombre de pistes de recherche sont discutées dans la dernière partie du texte.

  16. Morphological and biological features of seedlings of some Trifolium species

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    Valentina A. Kalinkina

    2013-04-01

    Full Text Available The author conducted morphological and biological characteristics of seedlings of six species belonging to three sections: Lupinaster(T. lupinasterL, T. pacificumBobr, T. eximium Steph. Ex. DC., Chronosemium(T. campestre Schreb. and Trifolium (T. arvenseL., T. pratense L. of the genus Trifolium. Dimensional and qualitative morphological characteristics of the main structural elements of the seedlings of these species are represented in the article.

  17. Effect of Hydrogen and Carbamide Peroxide in Bleaching, Enamel Morphology, and Mineral Composition: In vitro Study.

    Science.gov (United States)

    Llena, Carmen; Esteve, Irene; Forner, Leopoldo

    2017-07-01

    The aim of the study was to evaluate the bleaching effect, morphological changes, and variations in calcium (Ca) and phosphate (P) in the enamel with hydrogen peroxide (HP) and carbamide peroxide (CP) after the use of different application regimens. Four groups of five teeth were randomly assigned, according to the treatment protocol: HP 37.5% applied for 30 or 60 minutes (HP30, HP60), CP 16% applied for 14 or 28 hours (CP14, CP28). Changes in dental color were evaluated, according to the following formula: ΔE = [(L a -L b ) 2 +(a a -a b ) 2 + (b a -b b ) 2 ] 1/2 . Enamel morphology and Ca and P compositions were evaluated by confocal laser scanning microscope and environmental scanning electron microscopy. ΔE HP30 was significantly greater than CP14 (10.37 ± 2.65/8.56 ± 1.40), but not between HP60 and CP28. HP60 shows greater morphological changes than HP30. No morphological changes were observed in the groups treated with CP. The reduction in Ca and P was significantly greater in HP60 than in CP28 (p tooth color; HP produced morphological changes and Ca and P a gradual decrease, while CP produced no morphological changes, and the decrease in mineral component was smaller. CP 16% applied during 2 weeks could be equally effective and safer for tooth whitening than to administer two treatment sessions with HP 37.5%.

  18. Pioglitazone improves the ability of learning and memory via activating ERK1/2 signaling pathway in the hippocampus of T2DM rats.

    Science.gov (United States)

    Gao, F; Zang, L; Wu, D Y; Li, Y J; Zhang, Q; Wang, H B; Tian, G L; Mu, Y M

    2017-06-09

    To explore the correlation between effect of PIO (pioglitazone, PIO) on learning as well as memory and ERK1/2 (extracellular signal regulated kinase 1/2, ERK1/2) pathway in T2DM (type 2 diabetes mellitus, T2DM) rats, further to elucidate the potential mechanism of PIO in improvement of learning and memory. 12-week-old male SD rats (number of 10 per group) were randomly divided into control group (CON), T2DM group (DM) and T2DM +PIO group (DM+PG). Rats in DM and DM+PG groups were given high fat diet for 20 weeks, then treated with Streptozotocin (27mg/kg) by intraperitoneal injection at 21week. After 72h, the FBG (fasting blood glucose, FBG) was greater than 7.0mmol/L can considered T2DM rats. DM+PG group was treated with PIO (10 mg·kg -1 ·d -1 ) by gavage daily. After Hyperinsulinemic-Euglycemic Clamp Study and Morris water maze test at 30-week, all of animals were sacrificed. The expressions of RKIP (Raf-1 kinase inhibitor protein, RKIP) and ERK1/2 in hippocampus were detected using Western Blot and real-time PCR. The FBG level: DM group (7.68±0.54mmol/L) was higher than CON group (5.35±0.63mmol/L) and DM+PG group (6.07±0.84mmol/L), the differences were considered statistically significant (P 0.05); The relative content of p-ERK1/2 protein in CON group and DM+PG group rats dorsal were higher than those in group DM, the difference was considered statistically significant (P0.05). Activation of ERK1/2 signal transduction pathway via reducing RKIP in the hippocampus may be one of the mechanisms of PIO to improve the learning and memory of the T2DM rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Input and Age-Dependent Variation in Second Language Learning: A Connectionist Account.

    Science.gov (United States)

    Janciauskas, Marius; Chang, Franklin

    2017-07-26

    Language learning requires linguistic input, but several studies have found that knowledge of second language (L2) rules does not seem to improve with more language exposure (e.g., Johnson & Newport, 1989). One reason for this is that previous studies did not factor out variation due to the different rules tested. To examine this issue, we reanalyzed grammaticality judgment scores in Flege, Yeni-Komshian, and Liu's (1999) study of L2 learners using rule-related predictors and found that, in addition to the overall drop in performance due to a sensitive period, L2 knowledge increased with years of input. Knowledge of different grammar rules was negatively associated with input frequency of those rules. To better understand these effects, we modeled the results using a connectionist model that was trained using Korean as a first language (L1) and then English as an L2. To explain the sensitive period in L2 learning, the model's learning rate was reduced in an age-related manner. By assigning different learning rates for syntax and lexical learning, we were able to model the difference between early and late L2 learners in input sensitivity. The model's learning mechanism allowed transfer between the L1 and L2, and this helped to explain the differences between different rules in the grammaticality judgment task. This work demonstrates that an L1 model of learning and processing can be adapted to provide an explicit account of how the input and the sensitive period interact in L2 learning. © 2017 The Authors. Cognitive Science - A Multidisciplinary Journal published by Wiley Periodicals, Inc.

  20. How do verbal short-term memory and working memory relate to the acquisition of vocabulary and grammar? A comparison between first and second language learners.

    Science.gov (United States)

    Verhagen, Josje; Leseman, Paul

    2016-01-01

    Previous studies show that verbal short-term memory (VSTM) is related to vocabulary learning, whereas verbal working memory (VWM) is related to grammar learning in children learning a second language (L2) in the classroom. In this study, we investigated whether the same relationships apply to children learning an L2 in a naturalistic setting and to monolingual children. We also investigated whether relationships with verbal memory differ depending on the type of grammar skill investigated (i.e., morphology vs. syntax). Participants were 63 Turkish children who learned Dutch as an L2 and 45 Dutch monolingual children (mean age = 5 years). Children completed a series of VSTM and VWM tasks, a Dutch vocabulary task, and a Dutch grammar task. A confirmatory factor analysis showed that VSTM and VWM represented two separate latent factors in both groups. Structural equation modeling showed that VSTM, treated as a latent factor, significantly predicted vocabulary and grammar. VWM, treated as a latent factor, predicted only grammar. Both memory factors were significantly related to the acquisition of morphology and syntax. There were no differences between the two groups. These results show that (a) VSTM and VWM are differentially associated with language learning and (b) the same memory mechanisms are employed for learning vocabulary and grammar in L1 children and in L2 children who learn their L2 naturalistically. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Iranian EFL and Indian ESL College Students' Beliefs about Reading Strategies in L2 (Creencias de estudiantes universitarios iraníes EFL e hindúes ESL acerca de las estrategias de lectura en L2)

    Science.gov (United States)

    Karbalaei, Alireza

    2010-01-01

    The notion of "learner beliefs" has garnered much attention in the field of second language acquisition. Although different studies have been conducted to study learners' beliefs about language learning, little research has looked into the issue of L2 readers' beliefs and their relations to reading strategies. This study investigated…

  2. Evidence from adult L1 Afrikaans L2 French

    African Journals Online (AJOL)

    results of this study show that a large number of the L2 learners had indeed acquired ... position in V2-languages (such as German) and in third position in non-V2 ... L1, allows construction types x and y but he will have no problem acquiring .... Modern Foreign Languages at Stellenbosch University at the time of testing.

  3. Genetic Diversity of Namibian Pennisetum glaucum (L.) R. BR. (Pearl Millet) Landraces Analyzed by SSR and Morphological Markers.

    Science.gov (United States)

    McBenedict, Billy; Chimwamurombe, Percy; Kwembeya, Ezekeil; Maggs-Kölling, Gillian

    2016-01-01

    Current Pennisetum glaucum (L.) R. BR. cultivars in Namibia have overall poor performance posing a threat to the nation's food security because this crop is staple for over 70% of the Namibian population. The crop suffers from undesirable production traits such as susceptibility to diseases, low yield, and prolonged reproductive cycle. This study aimed to understand the genetic diversity of the crop in Namibia by simple sequence repeats (SSRs) and morphology analysis. A total of 1441 genotypes were collected from the National Gene Bank representing all the Namibian landraces. A sample of 96 genotypes was further analyzed by SSR using Shannon-Wiener diversity index and revealed a value of 0.45 indicating low genetic diversity. Ordination using Principal Coordinate Analysis (PCoA) on SSR data confirmed clusters generated by UPGMA for the 96 P. glaucum accessions. UPGMA phenograms of 29 morphological characterized genotypes were generated for SSR and morphology data and the two trees revealed 78% resemblance. Lodging susceptibility, tillering attitude, spike density, fodder yield potential, early vigour, and spike shape were the phenotypic characters upon which some clusters were based in both datasets. It is recommended that efforts should be made to widen the current gene pool in Namibia.

  4. Genetic Diversity of Namibian Pennisetum glaucum (L. R. BR. (Pearl Millet Landraces Analyzed by SSR and Morphological Markers

    Directory of Open Access Journals (Sweden)

    Billy McBenedict

    2016-01-01

    Full Text Available Current Pennisetum glaucum (L. R. BR. cultivars in Namibia have overall poor performance posing a threat to the nation’s food security because this crop is staple for over 70% of the Namibian population. The crop suffers from undesirable production traits such as susceptibility to diseases, low yield, and prolonged reproductive cycle. This study aimed to understand the genetic diversity of the crop in Namibia by simple sequence repeats (SSRs and morphology analysis. A total of 1441 genotypes were collected from the National Gene Bank representing all the Namibian landraces. A sample of 96 genotypes was further analyzed by SSR using Shannon-Wiener diversity index and revealed a value of 0.45 indicating low genetic diversity. Ordination using Principal Coordinate Analysis (PCoA on SSR data confirmed clusters generated by UPGMA for the 96 P. glaucum accessions. UPGMA phenograms of 29 morphological characterized genotypes were generated for SSR and morphology data and the two trees revealed 78% resemblance. Lodging susceptibility, tillering attitude, spike density, fodder yield potential, early vigour, and spike shape were the phenotypic characters upon which some clusters were based in both datasets. It is recommended that efforts should be made to widen the current gene pool in Namibia.

  5. Grateloupia ramosa Wang & Luan sp. nov. (Halymeniaceae, Rhodophyta), a new species from China based on morphological evidence and comparative rbcL sequences

    Science.gov (United States)

    Cao, Cuicui; Liu, Miao; Guo, Shaoru; Zhao, Dan; Luan, Rixiao; Wang, Hongwei

    2016-03-01

    Grateloupia ramosa Wang & Luan sp. nov. (Halymeniaceae, Rhodophyta) is newly described from Hainan Province, southern China. The organism has the following morphological features: (1) purplish red, cartilaginous and lubricous thalli 5-10 cm in height; (2) compressed percurrent axes bearing abundant branches with opposite arrangement; (3) claw-like apices on top, constricted to 2-4 cm at the base; (4) cortex consisting of 3-6 layers of elliptical or anomalous cells and a medulla covered by compact medullary filaments; (5) reproductive structures distributed throughout the thallus, especially centralized at the bottom of the end portion of the branches; and (6) 4-celled Carpogonial branches and 3-celled auxiliary-cell branches, both of the Grateloupia-type. The morphological diff erences were supported by molecular phylogenetics based on ribulose-1, 5-bisphosphate carboxylase/oxygenase ( rbcL) gene sequence analysis. There was only a 1 bp divergence between specimens collected from Wenchang and Lingshui of Hainan province. The new species was embedded in the large Grateloupia clade of the Halymeniaceae. The pairwise distances between G. ramosa and other species within Grateloupia ranged from 26 to 105 bp, within pairwise distances of 13-111 bp between species of the large genus Grateloupia in Halymeniaceae. Thus, we propose this new species as G. ramosa Wang & Luan sp. nov.

  6. Dietary effects of faba-bean (Vicia faba L.) tannins on the morphology and function of the small-intestinal mucosa of weaned pigs

    NARCIS (Netherlands)

    Leeuwen, P. van; Jansman, A.J.M.; Wiebenga, J.; Koninkx, J.F.J.G.; Mouwen, J.M.V.M.

    1995-01-01

    The objective of the present study was to evaluate effects of condensed tannins in faba beans (Vicia faba L.) on morphological and functional variables of the small-intestinal mucosa of piglets. In an experiment with young piglets (8-17 kg body weight), fed on either a control diet or a diet

  7. Exploring the Relationship between Reading Strategy Use and Multiple Intelligences among Successful L2 Readers

    Science.gov (United States)

    Mirzaei, Azizullah; Rahimi Domakani, Masoud; Heidari, Najmeh

    2014-01-01

    Over the years, the multiple intelligences theory (MIT) proposed by Howard Gardner has renewed interest in learners' use of effective learning strategies and produced interesting results. This MIT-oriented study investigated the role of successful L2 readers' multiple intelligences in their effective use of reading strategies. To this end, a TOEFL…

  8. Individual Differences in L2 Processing of Multi-word Phrases: Effects of Working Memory and Personality

    NARCIS (Netherlands)

    Kerz, E.; Wiechmann, D.; Mitkov, R.

    2017-01-01

    There is an accumulating body of evidence that knowledge of the statistics of multiword phrases (MWP) facilitates native language learning and processing both in children and adults. However, less is known about whether adult second language (L2) learners are able to develop native-like sensitivity

  9. Tailoring the morphology and crystallinity of poly(L-lactide acid) electrospun membranes

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Clarisse; Sencadas, Vitor; Costa, Carlos Miguel; Lanceros-Mendez, Senentxu [Centro/Departamento de Fisica da Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Gomez Ribelles, Jose Luis, E-mail: lanceros@fisica.uminho.pt [Centro de Biomateriales e Ingenieria Tisular, Universidad Politecnica de Valencia, 46022 Valencia (Spain)

    2011-02-15

    Biodegradable poly(L-lactic acid) (PLLA) microfibers were prepared by electrospinning by varying the applied potential, solution flow rate and collector conditions. PLLA fibers with smoothly oriented and random morphologies were obtained and characterized by scanning electron microscopy. The optimum fiber orientation was obtained at 1000 rpm using a 20.3 cm diameter collecting drum, while for higher and lower drum rotation speeds, the rapid random motion of the jets resulted in a random fiber distribution. The deformation of the jet with rapid solidification during electrospinning often results in a metastable phase. PLLA electrospun fibers are amorphous but contain numerous crystal nuclei that rapidly grow when the sample is heated to 70-140 {sup 0}C. In this way, the degree of crystallinity of the fibers can be tailored between 0 and 50% by annealing. Infrared transmission spectra revealed that the processing conditions do not affect the PLLA samples at the molecular level and that the crystallinity of the samples is related to the presence of {alpha}-crystals.

  10. Effects of GA3 Pregerminative Treatment on Gentiana lutea L. var. aurantiaca Germination and Seedlings Morphology

    Directory of Open Access Journals (Sweden)

    Óscar González-López

    2014-01-01

    Full Text Available Gentiana lutea L. is widely used in bitter beverages and in medicine; Gentianae Radix is the pharmaceutical name of the root of G. lutea. These uses have generated a high demand. The wild populations of Gentiana lutea var. aurantiaca (M. Laínz M. Laínz have been decimated; it is necessary to establish guidelines for its cultivation. Gentian as most alpine species has dormant seeds. Dormancy can be removed by cold and by means of a gibberellic acid (GA3 treatment. However, cold treatments produce low germination percentages and GA3 treatments may produce off-type seedlings. So, the objective was to determine, for the first time, the presowing treatments that allow high germination rate and good seedling morphology. The best pregerminative doses of GA3 to break seed dormancy were 100, 500, and 1000 ppm, while the best doses to optimize the seedling habit were 50 and 100 ppm. This study provides, for the first time, a 100 ppm GA3 dose that led to a high germination rate and good seedling morphology, as the starting point for gentian regular cultivation.

  11. Effects of GA3 pregerminative treatment on Gentiana lutea L. var. aurantiaca germination and seedlings morphology.

    Science.gov (United States)

    González-López, Óscar; Casquero, Pedro A

    2014-01-01

    Gentiana lutea L. is widely used in bitter beverages and in medicine; Gentianae Radix is the pharmaceutical name of the root of G. lutea. These uses have generated a high demand. The wild populations of Gentiana lutea var. aurantiaca (M. Laínz) M. Laínz have been decimated; it is necessary to establish guidelines for its cultivation. Gentian as most alpine species has dormant seeds. Dormancy can be removed by cold and by means of a gibberellic acid (GA3) treatment. However, cold treatments produce low germination percentages and GA3 treatments may produce off-type seedlings. So, the objective was to determine, for the first time, the presowing treatments that allow high germination rate and good seedling morphology. The best pregerminative doses of GA3 to break seed dormancy were 100, 500, and 1000 ppm, while the best doses to optimize the seedling habit were 50 and 100 ppm. This study provides, for the first time, a 100 ppm GA3 dose that led to a high germination rate and good seedling morphology, as the starting point for gentian regular cultivation.

  12. Morphological, biochemical and sensory characteristics of black mulberry fruits (Morus nigra L.

    Directory of Open Access Journals (Sweden)

    Beáta Stehlíková

    2013-02-01

    Full Text Available This work aimed at the morphological, biochemical, technological and sensorial determination of black mulberry (Morus nigra L. – MN  fruitage and their utilization in the food production branches. For the experimental purposes were selected 50 genotypes of this population grown in the Pukanec surroundings. The medium fruitage weight determined in the selected collection ranged from 7.26 g (MN-1 to 1.42 g (MN-14, fruitage length in a range of 13.51 mm (MN-14 to 29.20 mm (MN-12 and the medium fruitage width  11.88 mm (MN-14 – 21.12 mm (MN-2. The variability of the evaluated traits varried from low to high degree. Juice yield from matured fruitage achieved 62.40 %. From black mulberry fruitages 16 food products were prepared – juice mixed with cream, yoghurt and/or curd (in several proportions and 3 confectionery products. Sensorial analyses showed significant differences among tested products. In the group of confectionery products was generally preferred the cream-mulberry cake. High values of antioxidative activity has been measured in the chocolate cake with a mulberry jam (36.90 – 28.43 %, followed by the cream-mulberry cake (29.78 – 12.71 % and the fresh mulberry juice (30.97 – 20.17 %. The antioxidation activities exerted generally higher values with the samples tested in water, when compared with those prepared in ethanol extract. Based on the gained results 4 genotypes were selected and recommended for the use in practice, as these provided relative high values of tested traits.doi:10.5219/234

  13. Effect of Amino Acids on Morphology of Hydrothermally Synthesized Hydroxyapatite Fibers

    Directory of Open Access Journals (Sweden)

    QI Mei-li

    2017-05-01

    Full Text Available Based on the basic principle of biomineralization, hydroxyapatite fiber (HAF with high crystallinity was fabricated via a hydrothermal route with Ca(NO32·4H2O and (NH42HPO4 as the resources, respectively. Effects of the addition of acidic amino acid L-glutamic acid (Glu, neutral amino acid L-phenylalanine (Phe and basic amino acid L-lysine (Lys on the phase composition and morphology of the obtained products were laid special emphasis on. The results show that the products obtained by using the three amino acids are all hydroxyapatite (HA phase with minor CaCO3 in some samples. Meanwhile, all of the amino acids inhibit the growth of the fibers. Spherical morphology exists when Glu is added, the homogeneity of the fibers deteriorates with the addition of Lys. However, rod-like fibers with good uniformity can be obtained with the addition of Phe.

  14. Emergent Learning and Learning Ecologies in Web 2.0

    Directory of Open Access Journals (Sweden)

    Roy Williams

    2011-03-01

    Full Text Available This paper describes emergent learning and situates it within learning networks and systems and the broader learning ecology of Web 2.0. It describes the nature of emergence and emergent learning and the conditions that enable emergent, self-organised learning to occur and to flourish. Specifically, it explores whether emergent learning can be validated and self-correcting and whether it is possible to link or integrate emergent and prescribed learning. It draws on complexity theory, communities of practice, and the notion of connectivism to develop some of the foundations for an analytic framework, for enabling and managing emergent learning and networks in which agents and systems co-evolve. It then examines specific cases of learning to test and further develop the analytic framework.The paper argues that although social networking media increase the potential range and scope for emergent learning exponentially, considerable effort is required to ensure an effective balance between openness and constraint. It is possible to manage the relationship between prescriptive and emergent learning, both of which need to be part of an integrated learning ecology.

  15. Effect of some plant growth promoting rhizobacteria and nitrogen fertilizer on morphological characteristics of german chamomile (Matricaria chamomilla L.

    Directory of Open Access Journals (Sweden)

    S. Dastborhan

    2016-04-01

    Full Text Available .In order to investigate the effects of plant growth promoting rhizobacteria and nitrogen fertilizer on morphological traits of german chamomile (Matricaria chamomilla L., a field experiment was carried out as factorial based on randomized complete block design with three replications in Research Farm of the Faculty of Agriculture, University of Tabriz, Iran, during 2007-2008. Factors were inoculation with plant growth promoting rhizobacteria (B0: no-inoculation, B1: inoculation with Azotobacter chroocuccum, B2: inoculation with Azospirillum lipoferum and B3: inoculation with a mixture of two bacteria and nitrogen fertilizer (N0:0, N1:50, N2:100 and N3:150 kgN.ha-1. Results showed that inoculation with bacteria significantly improved plant height, stem diameter, number of lateral branches, number of flowers per plant, dry weight of flowers, stems, leaves and total dry weight per plant. These traits were significantly similar for inoculation with Azotobacter, inoculation with Azospirillum and inoculation with a mixture of two bacteria. Effect of nitrogen fertilizer on all traits (except number of lateral branches was positive, but there were no significant differences among 50, 100 and 150 kg.ha-1 nitrogen. The highest and the lowest number and weight of flowers per plant were recorded for inoculation + 50 kg.ha-1 nitrogen application and no-inoculation + no-fertilizer, respectively. In general, application of biofertilizers had positive and significant effects on morphological traits of german chamomile. In addition, with adding 50 kg N.ha-1 the performance of bacteria increased and the highest flower yield were produced.

  16. The L2 Motivational Self System and L2 Achievement: A Study of Saudi EFL Learners

    Science.gov (United States)

    Moskovsky, Christo; Assulaimani, Turki; Racheva, Silvia; Harkins, Jean

    2016-01-01

    The research reported in this article explores the relationship between Dörnyei's (2005, 2009) Second Language Motivational Self System (L2MSS) and the L2 proficiency level of Saudi learners of English as a foreign language (EFL). Male and female participants (N = 360) responded to a questionnaire relating to the main components of L2MSS, the…

  17. Diversity evaluation based on morphological, physiological and isozyme variation in genetic resources of garlic (Allium sativum L.) collected worldwide.

    Science.gov (United States)

    Hirata, Sho; Abdelrahman, Mostafa; Yamauchi, Naoki; Shigyo, Masayoshi

    2016-11-26

    The aim of this study was to obtain primary information about the global diversity of garlic (Allium sativum L.) by evaluating morphological, physiological and isozyme variation. A total of 107 garlic accessions collected worldwide were grown in Yamaguchi, Japan. Five morphological traits (bulb weight, bulb diameter, number of cloves per bulb, number of bulbils and scape length) and one physiological trait (bolting period) of the collected garlic showed wide variation. Meanwhile, a total of 140 garlic accessions, including the 107 mentioned above, were characterized by leucine aminopeptidase (LAP) and phosphoglucoisomerase (PGI) isozyme analyses; they clearly showed polymorphisms in putative isozyme loci (Lap-1, Lap-2 and Pgi-1). Allelic frequencies were estimated in each group of accessions categorized by their geographical origin, and the observed (H o ) and expected (H e ) heterozygosities were calculated. The allelic frequencies differed between groups. A principal component analysis based on morpho-physiological data indicated a grouping of the garlic accessions into Central Asian and Northern Mediterranean groups as well as others. We discuss the roles of artificial and natural selection that may have caused differentiation in these traits, on the assumption that ancestral domesticated garlic populations have adapted in various regions using standing variation or mutations that accumulated during expansion, and have evolved along with human-preferred traits over a long history of cultivation.

  18. Nuclear morphology, polyploidy, and chromatin elimination in tissue culture of Allium fistulosum L.

    Directory of Open Access Journals (Sweden)

    Andrzej Joachimiak

    2011-01-01

    Full Text Available The morphology of cell nuclei in callus obtained from root-tip meristems of Allium fistulosum L. (Monocotyledoneae, Alliaceae was analysed. The most interesting phenomena observed in long-term callus culture were the different mechanisms of cell polyploidization, enlargement of telomeric segments of heterochromatin, and extensive chromatin elimination, associated with instability of nuclei size and DNA content. Protruding heterochromatin "spikes" were observed on the surface of some di- and polyploid nuclei. The presence of these spikes was connected with the formation of small heterochromatic micronuclei frequently found in the cytoplasm. It is suggested that these micronuclei are produced by direct elimination of heterochromatin from the interphase nuclei. Polyploid cells accumulated with each successive cell collection. The ploidy level attained by highly polyploid cells was 15C-220C. The shape of the nuclei and heterochromatin distribution suggest that polyploid nuclei in A. fistulosum tissue culture are produced by endoreduplication and by restitution cycles.

  19. Morphological Family Size Effects in Young First and Second Language Learners: Evidence of Cross-Language Semantic Activation in Visual Word Recognition

    Science.gov (United States)

    de Zeeuw, Marlies; Verhoeven, Ludo; Schreuder, Robert

    2012-01-01

    This study examined to what extent young second language (L2) learners showed morphological family size effects in L2 word recognition and whether the effects were grade-level related. Turkish-Dutch bilingual children (L2) and Dutch (first language, L1) children from second, fourth, and sixth grade performed a Dutch lexical decision task on words…

  20. 2L-PCA: a two-level principal component analyzer for quantitative drug design and its applications.

    Science.gov (United States)

    Du, Qi-Shi; Wang, Shu-Qing; Xie, Neng-Zhong; Wang, Qing-Yan; Huang, Ri-Bo; Chou, Kuo-Chen

    2017-09-19

    A two-level principal component predictor (2L-PCA) was proposed based on the principal component analysis (PCA) approach. It can be used to quantitatively analyze various compounds and peptides about their functions or potentials to become useful drugs. One level is for dealing with the physicochemical properties of drug molecules, while the other level is for dealing with their structural fragments. The predictor has the self-learning and feedback features to automatically improve its accuracy. It is anticipated that 2L-PCA will become a very useful tool for timely providing various useful clues during the process of drug development.

  1. Task Repetition Effects on L1 Use in EFL Child Task-Based Interaction

    Science.gov (United States)

    Azkarai, Agurtzane; García Mayo, María del Pilar

    2017-01-01

    Research has shown that tasks provide second language (L2) learners with many opportunities to learn the L2. Task repetition has been claimed to benefit L2 learning since familiarity with procedure and/or content gives learners the chance to focus on more specific aspects of language. Most research on task repetition has focused on adult…

  2. Application of the K-W-L Teaching and Learning Method to an Introductory Physics Course

    Science.gov (United States)

    Wrinkle, Cheryl Schaefer; Manivannan, Mani K.

    2009-01-01

    The K-W-L method of teaching is a simple method that actively engages students in their own learning. It has been used with kindergarten and elementary grades to teach other subjects. The authors have successfully used it to teach physics at the college level. In their introductory physics labs, the K-W-L method helped students think about what…

  3. Interspecific somatic hybridization between lettuce (Lactuca sativa) and wild species L. virosa.

    Science.gov (United States)

    Matsumoto, E

    1991-02-01

    Somatic hybrids between cultivated lettuce (Lactuca sativa) and a wild species L. virosa were produced by protoplast electrofusion. Hybrid selection was based on inactivation of L. sativa with 20mM iodoacetamide for 15 min, and the inability of L. virosa protoplasts to divide in the culture conditions used. Protoplasts were cultured in agarose beads in a revised MS media. In all 71 calli were formed and 21 of them differentiated shoots on LS medium containing 0.1mg/l NAA and 0.2mg/l BA. Most regenerated plants exhibited intermediate morphology. These plants were confirmed as hybrids by isoenzyme analysis. The majority of somatic hybrids had 2n=4x=36 chromosomes, and had more vigorous growth than either parent. Hybrids had normal flower morphology, but all were sterile.

  4. Facile synthesis of morphology-controlled Co3O4 nanostructures through solvothermal method with enhanced catalytic activity for H2O2 electroreduction

    Science.gov (United States)

    Cheng, Kui; Cao, Dianxue; Yang, Fan; Xu, Yang; Sun, Gaohui; Ye, Ke; Yin, Jinling; Wang, Guiling

    2014-05-01

    Hydrogen peroxide (H2O2) replaced oxygen (O2) as oxidant has been widely investigated due to its faster reduction kinetics, easier storage and handling than gaseous oxygen. The main challenge of using H2O2 as oxidant is the chemical decomposition. In this article, by using different C2H5OH/H2O volume ratio as the solvent, Co3O4 with different morphologies (nanosheet, nanowire, ultrafine nanowire net, nanobelts, and honeycomb-like) direct growth on Ni foam are synthesized via a simple solvothermal method for the first time. Results show that the introduction of ethanol could obviously improve the catalytic performance toward H2O2 electroreduction. The sample prepared in the solution with the C2H5OH/H2O volume ratio of 1:2 shows the best catalytic performance among the five samples and a current density of 0.214 A cm-2 is observed in 3.0 mol L-1 KOH + 0.5 mol L-1 H2O2 at -0.4 V (vs. Ag/AgCl KCl), which is much larger than that on the other metal oxides reported previously, almost comparable with the precious metals. This electrode of Co3O4 directly grown on Ni foam has superior mass transport property, which combining with its low-cost and facile preparation, make it a promising electrode for fuel cell using H2O2 as the oxidant.

  5. Genetic diversity based on morphological traits in walnut (Juglans regia L.) landraces from Karakoram region-I

    International Nuclear Information System (INIS)

    Hussain, I.; Sultan, A.; Shinwari, Z. K.

    2016-01-01

    Walnut is one of the most important nutritive nut crops and widely grown in Gilgit-Baltistan region of Pakistan. In the present study 19 local landraces were analyzed for morphological traits to investigate genetic diversity and identify promising landraces for cultivar development. Multivariate analyses showed high variation for morphological traits and nut and kernel characteristics. Cluster analyses depicted diversity among the local land races which separated them into 2 major clusters groups, showing more association to morphological differences. PCA revealed that the 1st four principal components (PCs) possessed Eigen value >1.0, where PC1 and PC2 contributed total variance of 41.65 percent and 23.42 percent respectively with total variance (65.05 percent) showing maximum factor loadings by kernel ratio, shell percent, kernel yield and nut width by the first two PCs. Pearson correlation coefficient among walnut landraces revealed positively significant correlation between shell yield and nut weight(r=0.96), kernel yield and nut width(r=0.85), whereas negative correlation were observed (r = -0.89 and r = -0.76) between kernel ratio with shell yield and nut weight respectively. A wide range of diversity was observed among the local landraces from Karakoram regions and the landrace HKK and GNAG were reported as promising one with highest kernel ratio. These landraces are potential for future breeding of nut crops with distinct morphological traits. (author)

  6. L1000CDS2: LINCS L1000 characteristic direction signatures search engine.

    Science.gov (United States)

    Duan, Qiaonan; Reid, St Patrick; Clark, Neil R; Wang, Zichen; Fernandez, Nicolas F; Rouillard, Andrew D; Readhead, Ben; Tritsch, Sarah R; Hodos, Rachel; Hafner, Marc; Niepel, Mario; Sorger, Peter K; Dudley, Joel T; Bavari, Sina; Panchal, Rekha G; Ma'ayan, Avi

    2016-01-01

    The library of integrated network-based cellular signatures (LINCS) L1000 data set currently comprises of over a million gene expression profiles of chemically perturbed human cell lines. Through unique several intrinsic and extrinsic benchmarking schemes, we demonstrate that processing the L1000 data with the characteristic direction (CD) method significantly improves signal to noise compared with the MODZ method currently used to compute L1000 signatures. The CD processed L1000 signatures are served through a state-of-the-art web-based search engine application called L1000CDS 2 . The L1000CDS 2 search engine provides prioritization of thousands of small-molecule signatures, and their pairwise combinations, predicted to either mimic or reverse an input gene expression signature using two methods. The L1000CDS 2 search engine also predicts drug targets for all the small molecules profiled by the L1000 assay that we processed. Targets are predicted by computing the cosine similarity between the L1000 small-molecule signatures and a large collection of signatures extracted from the gene expression omnibus (GEO) for single-gene perturbations in mammalian cells. We applied L1000CDS 2 to prioritize small molecules that are predicted to reverse expression in 670 disease signatures also extracted from GEO, and prioritized small molecules that can mimic expression of 22 endogenous ligand signatures profiled by the L1000 assay. As a case study, to further demonstrate the utility of L1000CDS 2 , we collected expression signatures from human cells infected with Ebola virus at 30, 60 and 120 min. Querying these signatures with L1000CDS 2 we identified kenpaullone, a GSK3B/CDK2 inhibitor that we show, in subsequent experiments, has a dose-dependent efficacy in inhibiting Ebola infection in vitro without causing cellular toxicity in human cell lines. In summary, the L1000CDS 2 tool can be applied in many biological and biomedical settings, while improving the extraction of

  7. Morpho-z: improving photometric redshifts with galaxy morphology

    Science.gov (United States)

    Soo, John Y. H.; Moraes, Bruno; Joachimi, Benjamin; Hartley, William; Lahav, Ofer; Charbonnier, Aldée; Makler, Martín; Pereira, Maria E. S.; Comparat, Johan; Erben, Thomas; Leauthaud, Alexie; Shan, Huanyuan; Van Waerbeke, Ludovic

    2018-04-01

    We conduct a comprehensive study of the effects of incorporating galaxy morphology information in photometric redshift estimation. Using machine learning methods, we assess the changes in the scatter and outlier fraction of photometric redshifts when galaxy size, ellipticity, Sérsic index, and surface brightness are included in training on galaxy samples from the SDSS and the CFHT Stripe-82 Survey (CS82). We show that by adding galaxy morphological parameters to full ugriz photometry, only mild improvements are obtained, while the gains are substantial in cases where fewer passbands are available. For instance, the combination of grz photometry and morphological parameters almost fully recovers the metrics of 5-band photometric redshifts. We demonstrate that with morphology it is possible to determine useful redshift distribution N(z) of galaxy samples without any colour information. We also find that the inclusion of quasar redshifts and associated object sizes in training improves the quality of photometric redshift catalogues, compensating for the lack of a good star-galaxy separator. We further show that morphological information can mitigate biases and scatter due to bad photometry. As an application, we derive both point estimates and posterior distributions of redshifts for the official CS82 catalogue, training on morphology and SDSS Stripe-82 ugriz bands when available. Our redshifts yield a 68th percentile error of 0.058(1 + z), and a outlier fraction of 5.2 per cent. We further include a deep extension trained on morphology and single i-band CS82 photometry.

  8. JNK1 Controls Dendritic Field Size in L2/3 and L5 of the Motor Cortex, Constrains Soma Size and Influences Fine Motor Coordination

    Directory of Open Access Journals (Sweden)

    Emilia eKomulainen

    2014-09-01

    Full Text Available Genetic anomalies on the JNK pathway confer susceptibility to autism spectrum disorders, schizophrenia and intellectual disability. The mechanism whereby a gain or loss of function in JNK signaling predisposes to these prevalent dendrite disorders, with associated motor dysfunction, remains unclear. Here we find that JNK1 regulates the dendritic field of L2/3 and L5 pyramidal neurons of the mouse motor cortex (M1, the main excitatory pathway controlling voluntary movement. In Jnk1-/- mice, basal dendrite branching of L5 pyramidal neurons is increased in M1, as is cell soma size, whereas in L2/3, dendritic arborization is decreased. We show that JNK1 phosphorylates rat HMW-MAP2 on T1619, T1622 and T1625 (Uniprot P15146 corresponding to mouse T1617, T1620, T1623, to create a binding motif, that is critical for MAP2 interaction with and stabilization of microtubules, and dendrite growth control. Targeted expression in M1 of GFP-HMW-MAP2 that is pseudo-phosphorylated on T1619, T1622 and T1625 increases dendrite complexity in L2/3 indicating that JNK1 phosphorylation of HMW-MAP2 regulates the dendritic field. Consistent with the morphological changes observed in L2/3 and L5, Jnk1-/- mice exhibit deficits in limb placement and motor coordination, while stride length is reduced in older animals. In summary, JNK1 phosphorylates HMW-MAP2 to increase its stabilization of microtubules while at the same time controlling dendritic fields in the main excitatory pathway of M1. Moreover, JNK1 contributes to normal functioning of fine motor coordination. We report for the first time, a quantitative sholl analysis of dendrite architecture, and of motor behavior in Jnk1-/- mice. Our results illustrate the molecular and behavioral consequences of interrupted JNK1 signaling and provide new ground for mechanistic understanding of those prevalent neuropyschiatric disorders where genetic disruption of the JNK pathway is central.

  9. Lead Exposure Impairs Hippocampus Related Learning and Memory by Altering Synaptic Plasticity and Morphology During Juvenile Period.

    Science.gov (United States)

    Wang, Tao; Guan, Rui-Li; Liu, Ming-Chao; Shen, Xue-Feng; Chen, Jing Yuan; Zhao, Ming-Gao; Luo, Wen-Jing

    2016-08-01

    Lead (Pb) is an environmental neurotoxic metal. Pb exposure may cause neurobehavioral changes, such as learning and memory impairment, and adolescence violence among children. Previous animal models have largely focused on the effects of Pb exposure during early development (from gestation to lactation period) on neurobehavior. In this study, we exposed Sprague-Dawley rats during the juvenile stage (from juvenile period to adult period). We investigated the synaptic function and structural changes and the relationship of these changes to neurobehavioral deficits in adult rats. Our results showed that juvenile Pb exposure caused fear-conditioned memory impairment and anxiety-like behavior, but locomotion and pain behavior were indistinguishable from the controls. Electrophysiological studies showed that long-term potentiation induction was affected in Pb-exposed rats, and this was probably due to excitatory synaptic transmission impairment in Pb-exposed rats. We found that NMDA and AMPA receptor-mediated current was inhibited, whereas the GABA synaptic transmission was normal in Pb-exposed rats. NR2A and phosphorylated GluR1 expression decreased. Moreover, morphological studies showed that density of dendritic spines declined by about 20 % in the Pb-treated group. The spine showed an immature form in Pb-exposed rats, as indicated by spine size measurements. However, the length and arborization of dendrites were unchanged. Our results suggested that juvenile Pb exposure in rats is associated with alterations in the glutamate receptor, which caused synaptic functional and morphological changes in hippocampal CA1 pyramidal neurons, thereby leading to behavioral changes.

  10. Learning morphological phenomena of Modern Greek an exploratory approach

    OpenAIRE

    Kotsanis, Y.; Dimitrios, A. Kokkinos; Manousopoulou, A.G.; Papakonstantinou, G.

    1996-01-01

    Educational technology is influenced by and closely related to the fields of generative epistemology, Artificial Intelligence, and the learning sciences. Relevant research literature refers to the term constructionism (Papert, 1993) and exploratory learning (diSessa et al, 1995). Constructionism and exploratory learning are a synthesis of the constructivist theory of Piaget and the opportunities offered by technology to education on thinking concretely, on learning while constructing intellig...

  11. Improving word coverage using unsupervised morphological analyser

    Indian Academy of Sciences (India)

    To enable a computer to process information in human languages, ... vised morphological analyser (UMA) would learn how to analyse a language just by looking ... result for English, but they did remarkably worse for Finnish and Turkish.

  12. Exact solutions of sl-boson system in U(2l + 1) reversible O(2l + 2) transitional region

    CERN Document Server

    Zhang Xin

    2002-01-01

    Exact eigen-energies and the corresponding wavefunctions of the interacting sl-boson system in U(2l + 1) reversible O(2l +2) transitional region are obtained by using an algebraic Bethe Ansatz with the infinite dimensional Lie algebraic technique. Numerical algorithm for solving the Bethe Ansatz equations by using mathematical package is also outlined

  13. Rational Design and Synthesis of Carboxylate Gemini Surfactants with an Excellent Aggregate Behavior for Nano-La2O3 Morphology-Controllable Preparation.

    Science.gov (United States)

    Liao, Xueming; Gao, Zhinong; Xia, Yan; Niu, Fei; Zhai, Wenzhong

    2017-04-04

    A series of carboxylate gemini surfactants (CGS, C n -Φ-C n , n = 12, 14, 16, 18) with diphenyl ketone as a spacer group were prepared using a simple and feasible synthetic method. These CGS exhibited an excellent surface activity with extremely low critical micelle concentration (CMC) value (approximately 10 -5 mol/L), good performance in reducing surface tension (nearly 30 mN/m), and the ability of molecular self-assembly into different aggregate morphologies via adjusting the concentrations, which is attributed to the introduction of diphenyl ketone and carboxylic acid ammonium salt in the molecular structure. Moreover, the surface activity and self-assembly ability of CGS were further optimized by tuning the length of the tail chain. These excellent properties imply that CGS can be a soft template to prepare nanomaterials, especially in morphology-controllable synthesis. By adjusting the concentration of one of CGS (C 12 -Φ-C 12 ), nano-La 2 O 3 particles with diverse morphologies were obtained, including spherical shape, bead-chain shape, rod shape, velvet-antler shape, cedar shape, and bowknot shape. This work offers a vital insight into the rational design of template agents for the development of morphology-controllable nanomaterials.

  14. Fra web 2.0 til læringsspil 2.0

    DEFF Research Database (Denmark)

    Duus Henriksen, Thomas

    2010-01-01

    Artiklen sætter fokus på, hvordan man kan omsætte web 2.0-teknologien til læringsspil for derigennem at skabe en brugerbaseret, deltagerdreven tilgang til at arbejde med læringsspil. Artiklen beretter om, hvordan organisationsudviklingsspillet 6Styles omsættes, først til en skoleudviklingssammenh......Artiklen sætter fokus på, hvordan man kan omsætte web 2.0-teknologien til læringsspil for derigennem at skabe en brugerbaseret, deltagerdreven tilgang til at arbejde med læringsspil. Artiklen beretter om, hvordan organisationsudviklingsspillet 6Styles omsættes, først til en...... skoleudviklingssammenhæng og dernæst til et såkaldt 2.0-læringsspil, hvor deltagerne skaber læringsspillets indhold, mens de spiller spillet. Erfaringer fra brug af læringsspillet peger på, at 1) 2.0 læringsspil tager markant mere tid at anvende, 2) deltagerne udvikler en produktiv forståelse for den underliggende teori...

  15. TENCompetence Learning Design Toolkit, Runtime component, ccsi_v3_2_10c_v1_4

    NARCIS (Netherlands)

    Sharples, Paul; Popat, Kris; Llobet, Lau; Santos, Patricia; Hernández-Leo, Davinia; Miao, Yongwu; Griffiths, David; Beauvoir, Phillip

    2010-01-01

    Sharples, P., Popat, K., Llobet, L., Santos, P., Hernandez-Leo, D., Miao, Y., Griffiths, D. & Beauvoir, P. (2009) TENCompetence Learning Design Toolkit, Runtime component, ccsi_v3_2_10c_v1_4 This release is composed of three files corresponding to CopperCore Service Integration (CCSI) v3.2-10cv1.4,

  16. Whence the fuzziness? Morphological effects in interacting sound changes in Southern British English

    Directory of Open Access Journals (Sweden)

    Patrycja Strycharczuk

    2017-04-01

    Full Text Available The fronting of the high-back /uː/ and /ʊ/, as currently seen in Southern British English (SBE, is a rare opportunity to study two similar sound changes at different stages of their phonetic development: /uː/-fronting is a more advanced change than /ʊ/-fronting. Since the fronting in both vowels is restricted from applying before a following final /l/ (e.g., in words like 'fool 'or 'pull', we can exploit the difference in the phonetic advancement of /uː/ and /ʊ/-fronting to illuminate the nature of ‘fuzzy contrasts’ affecting vowel+/l/ sequences in morphologically complex words. As recent results show that /uː/-fronting is partially limited in 'fool-ing '(but not in monomorphemes like 'hula', we ask whether similar morphological constraints affect /ʊ/ followed by /l/ (e.g., 'bully 'vs. 'pull-ing'. Simultaneously, we consider the question of what phonological generalization best captures the interaction between vowel fronting, /l/-darkening, and morphological structure. We present ultrasound data from 20 speakers of SBE representing two age groups. The data show that morphologically conditioned contrasts are consistent for /uː/+/l/, but variable and limited in size for /ʊ/+/l/. We relate these findings to the debate on morphology-phonetics interactions and the emergence of phonological abstraction.

  17. Apport de l'analyse des réseaux sociaux à l'étude des communautés d'apprentissage en ligne Using social network analysis for the study of online learning communities

    Directory of Open Access Journals (Sweden)

    Cédric Sarré

    2012-09-01

    Full Text Available S'il est vrai que de nombreuses recherches ont porté, ces vingt dernières années, sur l'apport de la communication médiatisée par ordinateur (CMO à l'acquisition des langues secondes (L2, peu de travaux se sont intéressés à ce jour à la CMO à base orale (audioconférence et visioconférence et à ses différences et similitudes avec la CMO à base écrite. Cet article se propose d'examiner et de comparer les interactions entre apprenants générées lors de la réalisation de tâches collaboratives en anglais L2 selon trois modes de CMO : le clavardage, la visioconférence et le forum électronique. Les tâches collaboratives ont été proposées aux apprenants dans le cadre du dispositif hybride English for biologists dont l'objectif principal était de favoriser le développement de leur compétence interactionnelle en L2. L'analyse sociométrique des échanges nous permet de mettre en évidence l'influence du mode de CMO utilisé sur la charge interactionnelle (degré de prise en compte de l'autre et sur la configuration des interactions, ainsi que sur l'efficacité de la télécollaboration. Nous en tirons également des conclusions relatives à l'impact du mode de CMO sur l'entrée des apprenants dans la communauté d'apprentissage qui émerge de chacun des groupes de travail auquel ils appartiennent.In spite of the amount of published research on the use of computer-mediated communication (CMC in second language acquisition (SLA in the past twenty years, few of these studies deal with voice-based CMC (audioconferencing and videoconferencing and with how it compares with text-based CMC. This article aims at bridging this gap by examining and comparing learner-to-learner interactions in L2 English that were generated during the completion of collaborative tasks using three different CMC modes: text chat, desktop videoconferencing and discussion board. The collaborative tasks to be completed were part of a blended learning system

  18. It takes biking to learn: Physical activity improves learning a second language.

    Science.gov (United States)

    Liu, Fengqin; Sulpizio, Simone; Kornpetpanee, Suchada; Job, Remo

    2017-01-01

    Recent studies have shown that concurrent physical activity enhances learning a completely unfamiliar L2 vocabulary as compared to learning it in a static condition. In this paper we report a study whose aim is twofold: to test for possible positive effects of physical activity when L2 learning has already reached some level of proficiency, and to test whether the assumed better performance when engaged in physical activity is limited to the linguistic level probed at training (i.e. L2 vocabulary tested by means of a Word-Picture Verification task), or whether it extends also to the sentence level (which was tested by means of a Sentence Semantic Judgment Task). The results show that Chinese speakers with basic knowledge of English benefited from physical activity while learning a set of new words. Furthermore, their better performance emerged also at the sentential level, as shown by their performance in a Semantic Judgment task. Finally, an interesting temporal asymmetry between the lexical and the sentential level emerges, with the difference between the experimental and control group emerging from the 1st testing session at the lexical level but after several weeks at the sentential level.

  19. Bio-functionalizing of α-MnO{sub 2} nanorods with natural L-amino acids: A favorable adsorbent for the removal of Cd(II) ions

    Energy Technology Data Exchange (ETDEWEB)

    Mallakpour, Shadpour, E-mail: mallak@cc.iut.ac.ir [Organic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of); Nanotechnology and Advanced Materials Institute, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of); Motirasoul, Forough [Organic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Islamic Republic of Iran (Iran, Islamic Republic of)

    2017-04-15

    α-MnO{sub 2} nanorods were prepared by hydrothermal method and then the surface of these nanorods were covalently biofunctionalized with natural L-amino acids (alanine, phenylalanine, leucine, isoleucine, methionine, and valine). The modified α-MnO{sub 2} nanorods were analyzed by Fourier transform infrared spectroscopy and X-ray diffraction. Morphological studies were carried out by field emission scanning electron microscopy and transmission electron microscopy. The morphology of nanorods was improved after biofunctionalization and aggregation was reduced. In addition, the thermal gravimetric analysis was used for demonstrating a successful grafting of amino acids to the surface of α-MnO{sub 2} nanorods and determine the degree of functionalization. The amount of amino acids grafted onto α-MnO{sub 2} surface was estimated to be 5–32 wt%. Finally, the α-MnO{sub 2} and α-MnO{sub 2}-L-valine were investigated as adsorbents for the removal of cadmium ions from aqueous solution. The results showed that they have a potential to be used as effective adsorbents for cadmium ions removal from the aqueous solution. The equilibrium adsorption data showed the best fit for the pseudo-second-order and the Freundlich models. - Highlights: • α-MnO{sub 2} nanorods were biofunctionalized with natural L-amino acids. • Biofunctionalized α-MnO{sub 2} nanorods by solvothermal strategy were fully characterized. • Cadmium adsorption property of α-MnO{sub 2} and α-MnO{sub 2}-L-valine was studied.

  20. On the Role of Cognitive Abilities in Second Language Vowel Learning.

    Science.gov (United States)

    Ghaffarvand Mokari, Payam; Werner, Stefan

    2018-03-01

    This study investigated the role of different cognitive abilities-inhibitory control, attention control, phonological short-term memory (PSTM), and acoustic short-term memory (AM)-in second language (L2) vowel learning. The participants were 40 Azerbaijani learners of Standard Southern British English. Their perception of L2 vowels was tested through a perceptual discrimination task before and after five sessions of high-variability phonetic training. Inhibitory control was significantly correlated with gains from training in the discrimination of L2 vowel pairs. However, there were no significant correlations between attention control, AM, PSTM, and gains from training. These findings suggest the potential role of inhibitory control in L2 phonological learning. We suggest that inhibitory control facilitates the processing of L2 sounds by allowing learners to ignore the interfering information from L1 during training, leading to better L2 segmental learning.

  1. Difficulty in Learning Similar-Sounding Words: A Developmental Stage or a General Property of Learning?

    Science.gov (United States)

    Pajak, Bozena; Creel, Sarah C.; Levy, Roger

    2016-01-01

    How are languages learned, and to what extent are learning mechanisms similar in infant native-language (L1) and adult second-language (L2) acquisition? In terms of vocabulary acquisition, we know from the infant literature that the ability to discriminate similar-sounding words at a particular age does not guarantee successful word-meaning…

  2. Has Web 2.0 Revitalized Informal Learning? The Relationship between Web 2.0 and Informal Learning

    Science.gov (United States)

    Song, D.; Lee, J.

    2014-01-01

    Learning is becoming increasingly self-directed and often occurs away from schools and other formal educational settings. The development of a myriad of new technologies for learning has enabled people to learn anywhere and anytime. Web 2.0 technology allows researchers to shed a new light on the importance and prevalence of informal learning.…

  3. L2, the minor capsid protein of papillomavirus

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Joshua W. [Department of Pathology, The Johns Hopkins University, Baltimore, MD 21287 (United States); Roden, Richard B.S., E-mail: roden@jhmi.edu [Department of Pathology, The Johns Hopkins University, Baltimore, MD 21287 (United States); Department of Oncology, The Johns Hopkins University, Baltimore, MD 21287 (United States); Department of Gynecology and Obstetrics, The Johns Hopkins University, Baltimore, MD 21287 (United States)

    2013-10-15

    The capsid protein L2 plays major roles in both papillomavirus assembly and the infectious process. While L1 forms the majority of the capsid and can self-assemble into empty virus-like particles (VLPs), L2 is a minor capsid component and lacks the capacity to form VLPs. However, L2 co-assembles with L1 into VLPs, enhancing their assembly. L2 also facilitates encapsidation of the ∼8 kbp circular and nucleosome-bound viral genome during assembly of the non-enveloped T=7d virions in the nucleus of terminally differentiated epithelial cells, although, like L1, L2 is not detectably expressed in infected basal cells. With respect to infection, L2 is not required for particles to bind to and enter cells. However L2 must be cleaved by furin for endosome escape. L2 then travels with the viral genome to the nucleus, wherein it accumulates at ND-10 domains. Here, we provide an overview of the biology of L2. - Highlights: • L2 is the minor antigen of the non-enveloped T=7d icosahedral Papillomavirus capsid. • L2 is a nuclear protein that can traffic to ND-10 and facilitate genome encapsidation. • L2 is critical for infection and must be cleaved by furin. • L2 is a broadly protective vaccine antigen recognized by neutralizing antibodies.

  4. L2, the minor capsid protein of papillomavirus

    International Nuclear Information System (INIS)

    Wang, Joshua W.; Roden, Richard B.S.

    2013-01-01

    The capsid protein L2 plays major roles in both papillomavirus assembly and the infectious process. While L1 forms the majority of the capsid and can self-assemble into empty virus-like particles (VLPs), L2 is a minor capsid component and lacks the capacity to form VLPs. However, L2 co-assembles with L1 into VLPs, enhancing their assembly. L2 also facilitates encapsidation of the ∼8 kbp circular and nucleosome-bound viral genome during assembly of the non-enveloped T=7d virions in the nucleus of terminally differentiated epithelial cells, although, like L1, L2 is not detectably expressed in infected basal cells. With respect to infection, L2 is not required for particles to bind to and enter cells. However L2 must be cleaved by furin for endosome escape. L2 then travels with the viral genome to the nucleus, wherein it accumulates at ND-10 domains. Here, we provide an overview of the biology of L2. - Highlights: • L2 is the minor antigen of the non-enveloped T=7d icosahedral Papillomavirus capsid. • L2 is a nuclear protein that can traffic to ND-10 and facilitate genome encapsidation. • L2 is critical for infection and must be cleaved by furin. • L2 is a broadly protective vaccine antigen recognized by neutralizing antibodies

  5. Learning Additional Languages as Hierarchical Probabilistic Inference: Insights From First Language Processing.

    Science.gov (United States)

    Pajak, Bozena; Fine, Alex B; Kleinschmidt, Dave F; Jaeger, T Florian

    2016-12-01

    We present a framework of second and additional language (L2/L n ) acquisition motivated by recent work on socio-indexical knowledge in first language (L1) processing. The distribution of linguistic categories covaries with socio-indexical variables (e.g., talker identity, gender, dialects). We summarize evidence that implicit probabilistic knowledge of this covariance is critical to L1 processing, and propose that L2/L n learning uses the same type of socio-indexical information to probabilistically infer latent hierarchical structure over previously learned and new languages. This structure guides the acquisition of new languages based on their inferred place within that hierarchy, and is itself continuously revised based on new input from any language. This proposal unifies L1 processing and L2/L n acquisition as probabilistic inference under uncertainty over socio-indexical structure. It also offers a new perspective on crosslinguistic influences during L2/L n learning, accommodating gradient and continued transfer (both negative and positive) from previously learned to novel languages, and vice versa.

  6. Quantitative assessment of morphology, T_1_ρ, and T_2 of shoulder cartilage using MRI

    International Nuclear Information System (INIS)

    Nardo, Lorenzo; Carballido-Gamio, Julio; Tang, Solomon; Lai, Andrew; Krug, Roland

    2016-01-01

    The aim of this study was to assess the feasibility of quantifying shoulder cartilage morphology and relaxometry in a clinically feasible scan time comparing different pulse sequences and assessing their reproducibility at 3 Tesla. Three pulse sequences were compared for morphological assessments of shoulder cartilage thickness and volume (SPGR, MERGE, FIESTA), while a combined T1ρ-T2 sequence was optimized for relaxometry measurements. The shoulders of six healthy subjects were scanned twice with repositioning, and the cartilage was segmented and quantified. The degree of agreement between the three morphological sequences was assessed using Bland-Altman plots, while the morphological and relaxometry reproducibility were assessed with root-mean-square coefficients of variation (RMS-CVs) Bland-Altman plots indicated good levels of agreement between the morphological assessments of the three sequences. The reproducibility of morphological assessments yielded RMS-CVs between 4.0 and 17.7 %. All sequences correlated highly (R > 0.9) for morphologic assessments with no statistically significant differences. For relaxometry assessments of humeral cartilage, RMS-CVs of 6.4 and 10.6 % were found for T1ρ and T2, respectively. The assessment of both cartilage morphology and relaxometry is feasible in the shoulder with SPGR, humeral head, and T1ρ being the more reproducible morphological sequence, anatomic region, and quantitative sequence, respectively. (orig.)

  7. Learn ggplot2 using Shiny App

    CERN Document Server

    Moon, Keon-Woong

    2016-01-01

    This book and app is for practitioners, professionals, researchers, and students who want to learn how to make a plot within the R environment using ggplot2, step-by-step without coding. In widespread use in the statistical communities, R is a free software language and environment for statistical programming and graphics. Many users find R to have a steep learning curve but to be extremely useful once overcome. ggplot2 is an extremely popular package tailored for producing graphics within R but which requires coding and has a steep learning curve itself, and Shiny is an open source R package that provides a web framework for building web applications using R without requiring HTML, CSS, or JavaScript. This manual—"integrating" R, ggplot2, and Shiny—introduces a new Shiny app, Learn ggplot2, that allows users to make plots easily without coding. With the Learn ggplot2 Shiny app, users can make plots using ggplot2 without having to code each step, reducing typos and error messages and allowing users to bec...

  8. Associating biosensing properties with the morphological structure of multilayers containing carbon nanotubes on field-effect devices

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Jose R. Jr. [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos (Brazil); Institute of Nano- and Biotechnologies, Aachen University of Applied Sciences, Juelich (Germany); Institute of Bio- and Nanosystems (IBN-2), Research Centre Juelich (Germany); Baecker, Matthias; Poghossian, Arshak; Schoening, Michael J. [Institute of Nano- and Biotechnologies, Aachen University of Applied Sciences, Juelich (Germany); Institute of Bio- and Nanosystems (IBN-2), Research Centre Juelich (Germany); Zucolotto, Valtencir; Oliveira, Osvaldo N. Jr. [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos (Brazil)

    2010-04-15

    The control of molecular architecture provided by the layer-by-layer (LbL) technique has led to enhanced biosensors, in which advantageous features of distinct materials can be combined. Full optimization of biosensing performance, however, is only reached if the film morphology is suitable for the principle of detection of a specific biosensor. In this paper, we report a detailed morphology analysis of LbL films made with alternating layers of single-walled carbon nanotubes (SWNTs) and polyamidoamine (PAMAM) dendrimers, which were then covered with a layer of penicillinase (PEN). An optimized performance to detect penicillin G was obtained with 6-bilayer SWNT/PAMAM LbL films deposited on p-Si-SiO{sub 2}-Ta{sub 2}O{sub 5} chips, used in biosensors based on a capacitive electrolyte-insulator-semiconductor (EIS) and a light-addressable potentiometric sensor (LAPS) structure, respectively. Field-emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) images indicated that the LbL films were porous, with a large surface area due to interconnection of SWNT into PAMAM layers. This morphology was instrumental for the adsorption of a larger quantity of PEN, with the resulting LbL film being highly stable. The experiments to detect penicillin were performed with constant-capacitance (ConCap) and constant-current (CC) measurements for EIS and LAPS sensors, respectively, which revealed an enhanced detection signal and sensitivity of ca. 100 mV/decade for the field-effect sensors modified with the PAMAM/SWNT LbL film. It is concluded that controlling film morphology is essential for an enhanced performance of biosensors, not only in terms of sensitivity but also stability and response time. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  9. Can Working Memory and Inhibitory Control Predict Second Language Learning in the Classroom?

    Directory of Open Access Journals (Sweden)

    Jared A. Linck

    2015-10-01

    Full Text Available The role of executive functioning in second language (L2 aptitude remains unclear. Whereas some studies report a relationship between working memory (WM and L2 learning, others have argued against this association. Similarly, being bilingual appears to benefit inhibitory control, and individual differences in inhibitory control are related to online L2 processing. The current longitudinal study examines whether these two components of executive functioning predict learning gains in an L2 classroom context using a pretest/posttest design. We assessed 25 university students in language courses, who completed measures of WM and inhibitory control. They also completed a proficiency measure at the beginning and end of a semester and reported their grade point average (GPA. WM was positively related to L2 proficiency and learning, but inhibitory control was not. These results support the notion that WM is an important component of L2 aptitude, particularly for predicting the early stages of L2 classroom learning.

  10. Learning morphological phenomena of modern Greek an exploratory approach

    Directory of Open Access Journals (Sweden)

    Y. Kotsanis

    1996-12-01

    Full Text Available Educational technology is influenced by and closely related to the fields of generative epistemology, Artificial Intelligence, and the learning sciences. Relevant research literature refers to the term constructionism (Papert, 1993 and exploratory learning (diSessa et al, 1995. Constructionism and exploratory learning are a synthesis of the constructivist theory of Piaget and the opportunities offered by technology to education on thinking concretely, on learning while constructing intelligible entities, and on interacting with multimedia objects, rather than the direct acquisition of knowledge and facts. These views are based on the approach that learners can take substantial control of their own learning in an appropriately designed physical and cultural environment (Harel, 1991. In parallel, most of the studies of the Vygotskian framework focus on the role of language in the learning procedure, considering conceptual thought to be impossible outside an articulated verbal thinking. Moreover, the specific use of words is considered to be the most relevant cause for childhood and adolescent differentiation (Vygotsky, 1962.

  11. L1 effects on the processing of grammatical gender in L2

    NARCIS (Netherlands)

    Sabourin, L; Foster-Cohen, S.; Nizegorodcew, A.

    2001-01-01

    This paper explores L1 effects on the L2 off-line processing of Dutch (grammatical gender) agreement The L2 participants had either German, English or a Romance language as their L1. Non-gender agreement (finiteness and agreement) was tested to ascertain the level of proficiency of the participants

  12. Comparing the Efficacy of Digital Flashcards versus Paper Flashcards to Improve Receptive and Productive L2 Vocabulary

    Science.gov (United States)

    Dizon, Gilbert; Tang, Daniel

    2017-01-01

    Several researchers have compared the efficacy of digital flashcards (DFs) versus paper flashcards (PFs) to improve L2 vocabulary and have concluded that using DFs is more effective (Azabdaftari & Mozaheb, 2012; Basoglu & Akdemir, 2010; Kiliçkaya & Krajka, 2010). However, these studies did not utilize vocabulary learning strategies…

  13. The Effect of Focus on Form and Task Complexity on L2 Learners' Oral Task Performance

    Science.gov (United States)

    Salimi, Asghar

    2015-01-01

    Second Language learners' oral task performance has been one of interesting and research generating areas of investigations in the field of second language acquisition specially, task-based language teaching and learning. The main purpose of the present study is to investigate the effect of focus on form and task complexity on L2 learners' oral…

  14. A facile strategy to design zeolite L crystals with tunable morphology and surface architecture.

    Science.gov (United States)

    Lupulescu, Alexandra I; Kumar, Manjesh; Rimer, Jeffrey D

    2013-05-01

    Tailoring the anisotropic growth rates of materials to achieve desired structural outcomes is a pervasive challenge in synthetic crystallization. Here we discuss a method to selectively control the growth of zeolite crystals, which are used extensively in a wide range of industrial applications. This facile method cooperatively tunes crystal properties, such as morphology and surface architecture, through the use of inexpensive, commercially available chemicals with specificity for binding to crystallographic surfaces and mediating anisotropic growth. We examined over 30 molecules as potential zeolite growth modifiers (ZGMs) of zeolite L (LTL type) crystallization. ZGM efficacy was quantified through a combination of macroscopic (bulk) and microscopic (surface) investigations that identified modifiers capable of dramatically altering the cylindrical morphology of LTL crystals. We demonstrate an ability to tailor properties critical to zeolite performance, such as external porous surface area, crystal shape, and pore length, which can enhance sorbate accessibility to LTL pores, tune the supramolecular organization of guest-host composites, and minimize the diffusion path length, respectively. We report that a synergistic combination of ZGMs and the judicious adjustment of synthesis parameters produce LTL crystals with unique surface features, and a range of length-to-diameter aspect ratios spanning 3 orders of magnitude. A systematic examination of different ZGM structures and molecular compositions (i.e., hydrophobicity and binding moieties) reveal interesting physicochemical properties governing their efficacy and specificity. Results of this study suggest this versatile strategy may prove applicable for a host of framework types to produce unrivaled materials that have eluded more conventional techniques.

  15. Exploring the Principles and Practices of One Teacher of L2 Speaking: The Importance of Reflecting on Practice

    Directory of Open Access Journals (Sweden)

    Thomas S. C. Farrell

    2018-01-01

    Full Text Available Teacher principles encompass a teacher’s stated assumptions, beliefs, and conceptions about acquiring and teaching a second language (L2. Due to the complex and diversified nature of how principles take form, an individual teacher’s principles will influence their judgements, perceptions and instructional decisions, thus affecting the outcome of classroom practices. Exploring teacher principles and their impact on classroom practices and vice versa is an invaluable and necessary component to research in L2 teaching and learning since it plays an influential role in instructional outcomes.This paper explores the nature of the principles/practice relationship through an investigative case study with an ESL teacher of L2 speaking. Additionally, the results of research on principles and practices related to L2 teaching when conducted by academics rarely gets back to teachers in the front lines. Thus the researchers shared their findings with the teacher who as a result of reflecting on the analysis came up with a set of principles she says guides her teaching of L2 speaking.

  16. L1 and L2 Spoken Word Processing: Evidence from Divided Attention Paradigm.

    Science.gov (United States)

    Shafiee Nahrkhalaji, Saeedeh; Lotfi, Ahmad Reza; Koosha, Mansour

    2016-10-01

    The present study aims to reveal some facts concerning first language (L 1 ) and second language (L 2 ) spoken-word processing in unbalanced proficient bilinguals using behavioral measures. The intention here is to examine the effects of auditory repetition word priming and semantic priming in first and second languages of these bilinguals. The other goal is to explore the effects of attention manipulation on implicit retrieval of perceptual and conceptual properties of spoken L 1 and L 2 words. In so doing, the participants performed auditory word priming and semantic priming as memory tests in their L 1 and L 2 . In a half of the trials of each experiment, they carried out the memory test while simultaneously performing a secondary task in visual modality. The results revealed that effects of auditory word priming and semantic priming were present when participants processed L 1 and L 2 words in full attention condition. Attention manipulation could reduce priming magnitude in both experiments in L 2 . Moreover, L 2 word retrieval increases the reaction times and reduces accuracy on the simultaneous secondary task to protect its own accuracy and speed.

  17. L2 writing and L2 written feedback in upper secondary schools as experienced by teachers

    OpenAIRE

    Manousou, Angeliki

    2015-01-01

    L2 written feedback is a multi-faceted issue and this is the reason behind the big number of studies that have been conducted on it. However, the majority of studies deal with learners’ opinions of teachers’ feedback or several types of feedback and their advantages and disadvantages. There are no studies that could have addressed teachers’ opinions of their L2 written feedback. This study attempts to describe how L2 teachers view their written feedback on learners’ essays. ...

  18. Digital Affordances on WeChat: Learning Chinese as a Second Language

    Science.gov (United States)

    Jin, Li

    2018-01-01

    Different from the traditional term language input, affordance, an ecological term, has been deployed to analyze the perceived opportunities for second language (L2) learning an environment provides to L2 learners. L2 learning occurs only when the semiotic resources in the environment resonate with the learner's capacities such as their abilities,…

  19. Caracterização estrutural, textural e morfológica de aluminato de lítio (LiAlO2 sintetizado por coprecipitação Structural, textural and morphological characterization of lithium aluminate (LiAlO2 synthesized by coprecipitation

    Directory of Open Access Journals (Sweden)

    A. C. Nascimento

    2012-12-01

    Full Text Available Aluminato de lítio (LiAlO2 foi sintetizado por coprecipitação. O material foi calcinado em diferentes temperaturas e caracterizado por difração de raios X, espectroscopia na região do infravermelho com transformada de Fourier, adsorção gasosa, microscopia eletrônica de varredura (MEV e microscopia eletrônica de transmissão (MET, possibilitando sua caracterização estrutural, morfológica e textural. Diferentes fases cristalinas foram observadas à medida que a temperatura foi elevada de 550 para 1150 ºC. Texturalmente o material foi classificado como não-poroso e particulado a 550 e 750 ºC, apresentando microporos a 950 ºC. Análises comparativas de imagens de MET e MEV possibilitaram a identificação nanoflocos e microfolhas como as principais morfologias presentes no material.Lithium aluminate (LiAlO2 was synthesized by coprecipitation. The material was calcined at different temperatures and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, gas adsorption, scanning electron microscopy (SEM and transmission electron microscopy (TEM, providing a structural, morphological and textural characterization. Different crystalline phases were observed as the temperature was raised from 550 to 1150 ºC. Texturally, the material was classified as non-porous and particulate at 550 and 750 ºC showing micropores at 950 ºC. Comparative analysis of TEM and SEM images allowed the identification of nanoflakes and microsheets as the main morphology present in the material.

  20. Delayed vertebral diagnosed L4 pincer vertebral fracture, L2-L3 ruptured vertebral lumbar disc hernia, L5 vertebral wedge fracture - Case report

    Directory of Open Access Journals (Sweden)

    Balasa D

    2016-08-01

    Full Text Available An association between delayed ruptured lumbar disc hernia, L5 vertebral wedge fracture and posttraumaticL4 pincer vertebral fracture (A2.3-AO clasification at different levels is a very rare entity. We present the case of a 55 years old male who falled down from a bicycle. 2 months later because of intense and permanent vertebral lumbar and radicular L2 and L3 pain (Visual Scal Autologus of Pain7-8/10 the patient came to the hospital. He was diagnosed with pincer vertebral L4 fracture (A2.3-AO clasification and L2-L3 right ruptured lumbar disc hernia in lateral reces. The patient was operated (L2-L3 right fenestration, and resection of lumbar disc hernia, bilateral stabilisation, L3-L4-L5 with titan screws and postero-lateral bone graft L4 bilateral harvested from iliac crest.

  1. A transmembrane polar interaction is involved in the functional regulation of integrin alpha L beta 2.

    Science.gov (United States)

    Vararattanavech, Ardcharaporn; Chng, Choon-Peng; Parthasarathy, Krupakar; Tang, Xiao-Yan; Torres, Jaume; Tan, Suet-Mien

    2010-05-14

    Integrins are heterodimeric transmembrane (TM) receptors formed by noncovalent associations of alpha and beta subunits. Each subunit contains a single alpha-helical TM domain. Inside-out activation of an integrin involves the separation of its cytoplasmic tails, leading to disruption of alphabeta TM packing. The leukocyte integrin alpha L beta 2 is required for leukocyte adhesion, migration, proliferation, cytotoxic function, and antigen presentation. In this study, we show by mutagenesis experiments that the packing of alpha L beta 2 TMs is consistent with that of the integrin alpha IIb beta 3 TMs. However, molecular dynamics simulations of alpha L beta 2 TMs in lipids predicted a polar interaction involving the side chains of alpha L Ser1071 and beta2 Thr686 in the outer-membrane association clasp (OMC). This is supported by carbonyl vibrational shifts observed in isotope-labeled alpha L beta 2 TM peptides that were incorporated into lipid bilayers. Molecular dynamics studies simulating the separation of alpha L beta 2 tails showed the presence of polar interaction during the initial perturbation of the inner-membrane association clasp. When the TMs underwent further separation, the polar interaction was disrupted. OMC polar interaction is important in regulating the functions of beta2 integrins because mutations that disrupt the OMC polar interaction generated constitutively activated alpha L beta 2, alpha M beta 2, and alpha X beta 2 in 293T transfectants. We also show that the expression of mutant beta2 Thr686Gly in beta2-deficient T cells rescued cell adhesion to intercellular adhesion molecule 1, but the cells showed overt elongated morphologies in response to chemokine stromal-cell-derived factor 1 alpha treatment as compared to wild-type beta2-expressing cells. These two TM polar residues are totally conserved in other members of the beta2 integrins in humans and across different species. Our results provide an example of the stabilizing effect of polar

  2. Pectin of Prunus domestica L. alters sulfated structure of cell-surface heparan sulfate in differentiated Caco-2 cells through stimulation of heparan sulfate 6-O-endosulfatase-2.

    Science.gov (United States)

    Nishida, Mitsutaka; Murata, Kazuma; Kanamaru, Yoshihiro; Yabe, Tomio

    2014-01-01

    Although previous reports have suggested that pectin induces morphological changes of the small intestine in vivo, the molecular mechanisms have not been elucidated. As heparan sulfate plays important roles in development of the small intestine, to verify the involvement of heparan sulfate (HS) in the pectin-induced morphological changes of the small intestine, the effects of pectin from Prunus domestica L. on cell-surface HS were investigated using differentiated Caco-2 cells. Disaccharide compositional analysis revealed that sulfated structures of HS were markedly changed by pectin administration. Real-time RT-PCR showed that pectin upregulated human HS 6-O-endosulfatase-2 (HSulf-2) expression and markedly inhibited HSulf-1 expression. Furthermore, inhibition analysis suggested that pretreatment with fibronectin III1C fragment, RGD peptide, and ERK1/2 inhibitor suppressed pectin-induced HSulf-2 expression. These observations indicate that pectin induced the expression of HSulf-2 through the interaction with fibronectin, α5β1 integrin, and ERK1/2, thereby regulating the sulfated structure of HS on differentiated Caco-2 cells.

  3. Microstructure, morphology and magnetic properties of Ni nanoparticles synthesized by hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Bouremana, A. [LPM, Faculty of Sciences, USTHB, BP 32, El-Alia, Bab Ezzouar, Algiers (Algeria); Guittoum, A., E-mail: aguittoum@gmail.com [Nuclear Research Centre of Algiers, 02 Bd Frantz Fanon, BP 399, Alger-Gare, Algiers (Algeria); Hemmous, M. [Nuclear Research Centre of Algiers, 02 Bd Frantz Fanon, BP 399, Alger-Gare, Algiers (Algeria); Martínez-Blanco, D. [SCTs, University of Oviedo, EPM, 33600 Mieres (Spain); Gorria, Pedro [Department of Physics & IUTA, EPI, University of Oviedo, 33203 Gijón (Spain); Blanco, J.A. [Department of Physics, University of Oviedo, Calvo Sotelo St., 33007 Oviedo (Spain); Benrekaa, N. [LPM, Faculty of Sciences, USTHB, BP 32, El-Alia, Bab Ezzouar, Algiers (Algeria)

    2015-06-15

    Powder samples containing high purity nickel nanoparticles (NPs) were prepared by hydrothermal method from Ni(II) chloride hexahydrate (NiCl{sub 2}·6H{sub 2}O) under the presence of sodium hydroxide (NaOH) with different concentrations between 5 and 25 mol/L. The synthesis of the NPs occurs through chemical reduction at relatively low temperature (140 °C). The Ni NPs have a face-centred cubic (fcc) crystal structure with a lattice parameter value close to that of pure Ni (a = 3.52 Å). The average crystallite size determined from x-ray diffraction is around 20 nm, except for the sample synthesized under the highest NaOH concentration (25 mol/L), which has the largest average size (>30 nm). The powder morphology at the sub-micrometre length scale looks like agglomerates of Ni-NPs that drastically changes their shape depending on the NaOH concentration, from flower (5 mol/L) to a dendritic-like (25 mol/L). All the samples are ferromagnetic at room temperature with saturation magnetization values between 50 and 52emu/g, and a coercive field that increases with the NaOH concentration from around 135 (5 mol/L) up to 180Oe (25 mol/L). - Highlights: • Pure Nickel nanoparticles have been synthesized by a chemical reaction process. • Different morphologies were observed with the change of NaOH concentration. • The coercive field increases with increasing the NaOH concentration and depends on the shape of nanoparticles.

  4. An overview of L-2-hydroxyglutarate dehydrogenase gene (L2HGDH) variants: a genotype-phenotype study

    DEFF Research Database (Denmark)

    Steenweg, Marjan E; Jakobs, Cornelis; Errami, Abdellatif

    2010-01-01

    L-2-Hydroxyglutaric aciduria (L2HGA) is a rare, neurometabolic disorder with an autosomal recessive mode of inheritance. Affected individuals only have neurological manifestations, including psychomotor retardation, cerebellar ataxia, and more variably macrocephaly, or epilepsy. The diagnosis of ...

  5. A Video-Based CALL Program for Proficient and Less-Proficient L2 Learners' Comprehension Ability, Incidental Vocabulary Acquisition

    Science.gov (United States)

    Lin, Lu-Fang

    2010-01-01

    This study investigates first whether news video in a computer-assisted language learning (CALL) program can foster second language (L2) comprehension and incidental acquisition of adjectives, nouns, and verbs. Second, this study examines the relationship between the participants' vocabulary acquisition and their video comprehension. The…

  6. Pattern of morphological diversification in the Leptocarabus ground beetles (Coleoptera: Carabidae) as deduced from mitochondrial ND5 gene and nuclear 28S rDNA sequences.

    Science.gov (United States)

    Kim, C G; Zhou, H Z; Imura, Y; Tominaga, O; Su, Z H; Osawa, S

    2000-01-01

    Most of the mitochondrial NADH dehydrogenase subunit 5 (ND5) gene and a part of nuclear 28S ribosomal RNA gene were sequenced for 14 species of ground beetles belonging to the genus Leptocarabus. In both the ND5 and the 28S rDNA phylogenetic trees of Leptocarabus, three major lineages were recognized: (1) L. marcilhaci/L. yokoael/Leptocarabus sp. from China, (2) L. koreanus/L. truncaticollis/L. seishinensis/L. semiopacus/L. canaliculatus/L. kurilensis from the northern Eurasian continent including Korea and Hokkaido, Japan, and (3) all of the Japanese species except L. kurilensis. Clustering of the species in the trees is largely linked to their geographic distribution and does not correlate with morphological characters. The species belonging to different species groups are clustered in the same lineages, and those in the same species group are scattered among the different lineages. One of the possible interpretations of the present results would be that morphological transformations independently took place in the different lineages, sometimes with accompanying parallel morphological evolution, resulting in the occurrence of the morphological species belonging to the same species group (= type) in the different lineages.

  7. THE MORPHOLOGICAL BASIS FOR OLFACTORY PERCEPTION OF STEROIDS DUING AGONISTIC BEHAVIOR IN LOBSTER: PRELIMINARY EXPERIMENTS

    Science.gov (United States)

    The morphological basis for olfactory perception of steroids during agonistic behavior in lobsters: preliminary experiments. Borsay Horowitz, DJ1, Kass-Simon, G2, Coglianese, D2, Martin, L2, Boseman, M2, Cromarty, S3, Randall, K3, Fini, A.3 1US EPA, NHEERL, ORD, Atlantic Ecology...

  8. Inter-hemispheric comparison of CO2 signals in leaf cuticle morphology

    NARCIS (Netherlands)

    Hincke, A.J.C.

    2016-01-01

    Despite on-going efforts to understand the effects of the complex CO2-vegetation relationship on plant morphology, a clear picture has not yet been established. In order to better understand and quantify past CO2 dynamics as they relate to hydrological processes and ecosystem interactions, intensive

  9. Effect of Gamma Irradiation on Morphological Traits in M1 Generation of Kenaf (Hibiscus cannabinus L.) V36 Variety

    International Nuclear Information System (INIS)

    Faiz Ahmad; Mohd Zulmadi Sani; Mustapha Akil

    2016-01-01

    Kenaf (Hibiscus cannabinus L.) is one of the world most economically important fiber crops particularly in Asian-Pacific region. Mutation induction is a method to increase genetic divergence associated with selection, recombination, or a combination of these approaches in plant breeding. The present study was aimed to evaluate the effects of selected gamma irradiation doses (200 Gy and 300 Gy) on the kenaf morphological traits in M1 generation. Irradiated and non-irradiated of kenaf seed from V36 variety were planted in the field at Beseri, Perlis. Soil condition at the field, morphological changes and 10 morphological traits of irradiated plants were observed and evaluated against the controls. Cluster analysis result on M1 progenies showed that the mutation observed were classified into eight genotypic groups. The first two components from principal component analysis explained about 77.99 % of variation. Number of seed per pod, weight of seed per plant and dry stem biomass play important role to explain the variation since they showed positive correlated values for the first component analysis. Thus, this study is important in determining the effectiveness of these doses in generating mutations. In addition, it can also be used to generate a new source of germplasm in kenaf with enhanced quality traits such as high yielding and high fiber content. (author)

  10. Morphological characterization of Capsicum annuum L. accessions from southern Mexico and their response to the Bemisia tabaci-Begomovirus complex

    Directory of Open Access Journals (Sweden)

    Horacio Ballina-Gomez

    2013-12-01

    Full Text Available The high diversity of chili pepper (Capsicum annuum L. in Mexico offers an excellent alternative to search for wild and semi-domesticated genotypes as sources of resistance to the complex Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae-Begomovirus, which has caused enormous losses in commercial production of various horticultural crops. The goal of the present work was to characterize ex situ 18 genotypes of C. annuum from southern Mexico through 47 morphological descriptors, and to evaluate its response to the B. tabaci-Begomovirus complex. Morphological characterization showed the variables calyx annular constriction (CAC, number of branch bifurcation (NBB, and calyx pigmentation (CP had the highest variation. Principal components analysis (PCA of 47 morphological characteristics showed that 12 components were selected as meaningful factors. These components explained 94% of the variation. Cluster analysis showed three major clusters and seven sub-clusters. On the other hand, evaluation of the response to B. tabaci-Begomovirus showed that the genotypes have differential susceptibility to this vector-pathogen complex. Genotypes 'Chawa', 'Blanco', 'Maax' and 'X'catic' were into the low susceptibility to B. tabaci and low severity of viral symptoms. Surprisingly, the genotype 'Simojovel' showed high susceptibility to whitefly, but was grouped into genotypes with low symptom severity. This study shows the potential of native germplasm of pepper to explore sources of resistance to the B. tabaci-Begomovirus complex.

  11. Web 2.0 in e-Learning

    Directory of Open Access Journals (Sweden)

    M. Tariq Banday

    2013-10-01

    Full Text Available Web 2.0 tools have created fresh opportunities for governments, education, businesses and individuals to enhance efficiency and improve effectiveness while executing respective professional duties. The key features of these tools include online character and access through a web browser, supportive for open content licenses, open sharing and social interaction, and often free to use or support free features. These have created novel prospects for teachers to combine face-to-face teaching and online materials via social media such as discussion forums, blogs and wikis. The web 2.0 educational design is based on socio-cultural learning theories such as interaction, joint creation of content, critical thinking, learning by doing and collaboration. This paper makes an appraisal of ICT adoption in education, emergence of Web, improvements in Web and its effect on the e-Learning. It explains gradual integration of ICT into education through various stages. The paper presents the content and communication dimensions of e-learning for its classification. It discusses various opportunities created by Web 2.0 tools in education for effective teacher-learner, learner-learner and teacher-teacher communication, interaction and collaboration. It presents various cases and projects involving use of some Web 2.0 tools for enhancing learning. Furthermore, it lists some challenges for successful implementation of e-learning through Web 2.0 tools and discusses some possible solutions for its control.

  12. Multitask Imidazolium Salt Additives for Innovative Poly(l-lactide) Biomaterials: Morphology Control, Candida spp. Biofilm Inhibition, Human Mesenchymal Stem Cell Biocompatibility, and Skin Tolerance.

    Science.gov (United States)

    Schrekker, Clarissa M L; Sokolovicz, Yuri C A; Raucci, Maria G; Selukar, Balaji S; Klitzke, Joice S; Lopes, William; Leal, Claudio A M; de Souza, Igor O P; Galland, Griselda B; Dos Santos, João Henrique Z; Mauler, Raquel S; Kol, Moshe; Dagorne, Samuel; Ambrosio, Luigi; Teixeira, Mário L; Morais, Jonder; Landers, Richard; Fuentefria, Alexandre M; Schrekker, Henri S

    2016-08-24

    Candida species have great ability to colonize and form biofilms on medical devices, causing infections in human hosts. In this study, poly(l-lactide) films with different imidazolium salt (1-n-hexadecyl-3-methylimidazolium chloride (C16MImCl) and 1-n-hexadecyl-3-methylimidazolium methanesulfonate (C16MImMeS)) contents were prepared, using the solvent casting process. Poly(l-lactide)-imidazolium salt films were obtained with different surface morphologies (spherical and directional), and the presence of the imidazolium salt in the surface was confirmed. These films with different concentrations of the imidazolium salts C16MImCl and C16MImMeS presented antibiofilm activity against isolates of Candida tropicalis, Candida parapsilosis, and Candida albicans. The minor antibiofilm concentration assay enabled one to determine that an increasing imidazolium salt content promoted, in general, an increase in the inhibition percentage of biofilm formation. Scanning electron microscopy micrographs confirmed the effective prevention of biofilm formation on the imidazolium salt containing biomaterials. Lower concentrations of the imidazolium salts showed no cytotoxicity, and the poly(l-lactide)-imidazolium salt films presented good cell adhesion and proliferation percentages with human mesenchymal stem cells. Furthermore, no acute microscopic lesions were identified in the histopathological evaluation after contact between the films and pig ear skin. In combination with the good morphological, physicochemical, and mechanical properties, these poly(l-lactide)-based materials with imidazolium salt additives can be considered as promising biomaterials for use in the manufacturing of medical devices.

  13. The Mixed Effects of Phonetic Input Variability on Relative Ease of L2 Learning: Evidence from English Learners’ Production of French and Spanish Stop-Rhotic Clusters

    Directory of Open Access Journals (Sweden)

    Laura Colantoni

    2018-04-01

    Full Text Available We examined the consequences of within-category phonetic variability in the input on non-native learners’ production accuracy. Following previous empirical research on the L2 acquisition of phonetics and the lexicon, we tested the hypothesis that phonetic variability facilitates learning by analyzing English-speaking learners’ production of French and Spanish word-medial stop-rhotic clusters, which differ from their English counterparts in terms of stop and rhotic voicing and manner. Crucially, for both the stops and rhotics, there are differences in within-language variability. Twenty native speakers per language and 39 L1 English-learners of French (N = 20 and Spanish (N = 19 of intermediate and advanced proficiency performed a carrier-sentence reading task. A given parameter was deemed to have been acquired when the learners’ production fell within the range of attested native speaker values. An acoustic analysis of the data partially supports the facilitative effect of phonetic variability. To account for the unsupported hypotheses, we discuss a number of issues, including the difficulty of measuring variability, the need to determine the extent to which learners’ perception shapes intake, and the challenge of teasing apart the effects of input variability from those of transferred L1 articulatory patterns.

  14. Morphological and molecular characterization of lymnaeid snails and their potential role in transmission of Fasciola spp. in Vietnam.

    Science.gov (United States)

    Dung, Bui Thi; Doanh, Pham Ngoc; The, Dang Tat; Loan, Ho Thi; Losson, Bertrand; Caron, Yannick

    2013-12-01

    Freshwater snails of the family Lymnaeidae play an important role in the transmission of fascioliasis worldwide. In Vietnam, 2 common lymnaeid species, Lymnaea swinhoei and Lymnaea viridis, can be recognized on the basis of morphology, and a third species, Lymnaea sp., is known to exist. Recent studies have raised controversy about their role in transmission of Fasciola spp. because of confusion in identification of the snail hosts. The aim of this study is, therefore, to clarify the identities of lymnaeid snails in Vietnam by a combination of morphological and molecular approaches. The molecular analyses using the second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA clearly showed that lymnaeids in Vietnam include 3 species, Austropeplea viridis (morphologically identified as L. viridis), Radix auricularia (morphologically identified as L. swinhoei) and Radix rubiginosa (morphologically identified as Lymnaea sp.). R. rubiginosa is a new record for Vietnam. Among them, only A. viridis was found to be infected with Fasciola spp. These results provide a new insight into lymnaeid snails in Vietnam. Identification of lymnaeid snails in Vietnam and their role in the liver fluke transmission should be further investigated.

  15. Effects of prior knowledge on learning from different compositions of representations in a mobile learning environment

    NARCIS (Netherlands)

    T.-C. Liu (Tzu-Chien); Y.-C. Lin (Yi-Chun); G.W.C. Paas (Fred)

    2014-01-01

    textabstractTwo experiments examined the effects of prior knowledge on learning from different compositions of multiple representations in a mobile learning environment on plant leaf morphology for primary school students. Experiment 1 compared the learning effects of a mobile learning environment

  16. Asimmetrie L1/L2: una sfida nella didattica di “lingua e traduzione”.

    Directory of Open Access Journals (Sweden)

    Laura Salmon

    2004-12-01

    Full Text Available Asymmetries Between L1 and L2: a Challenge in the Teaching of "Language and Translation" Language teaching is deeply connected to the cognitive and brain sciences. The attribution of meaning of linguistic messages depends on the interaction between the communicant’s brain and the external world. The interaction is based on the cognitive and emotional experience shared by a L-community. Competence in L2 is acquired by the development of an internal data base of contextualised .units of living speech. (Lurija 1976. L2 teaching is particularly successful when the L2 units are inscribed in memory by means of the functionally equivalent L1 units. Selection of the L1/L2 correspondent units is due to the principle of markedness: each unit of L1 has a functional equivalent in one and only one unit of the L2. Because of the interlingual asymmetries (a set of Italian/Russian examples is given, functional equivalence differs from morphosyntactic and lexical equivalence. The competency in ascribing a degree of markedness to each linguistic unit needs the regular implicit acquisition of the L2 intonational and prosodic system; the processes of the metalinguistic conscious reflection are instead a .hindrance. to the procedural acting of a “living speaker”.

  17. A Prerequisite to L1 Homophone Effects in L2 Spoken-Word Recognition

    Science.gov (United States)

    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…

  18. The literary critical discourse analysis as a useful tool for cultural learning in an L2 classroom

    Directory of Open Access Journals (Sweden)

    Claudia Asín-Cabrera

    2017-06-01

    Full Text Available The L2 teaching is an area very prone to the influences of different ideologies from other cultures. Due to this, the present article will be focused on the useful application of critical discourse analysis (CDA in L2 teaching to identify, interpret and understand such cultural elements, specifically, through the critical analysis of literary discourse. The scientific methods to be employed will be analysis-synthesis and induction-deduction in the processing and systematization of the information that leads to interpretations and generalizations of the main theoretical concepts this article deals with; and the theoretical premises CDA hinges on.

  19. Redesigning Introductory Science Courses to Teach Sustainability: Introducing the L(SC)2 Paradigm

    Science.gov (United States)

    Myers, J. D.; Campbell-Stone, E.; Massey, G.

    2008-12-01

    promoting scientific literacy, L(SC)2 courses explicitly promote mastery of fundamental quantitative and qualitative skills critical to science and commonly a barrier to student success in science. Scientific content addresses the principles and disciplines necessary to tackle the multifaceted problems that must be solved in any sustainability transition and illustrates the limitations on what can be accomplished. Finally, social context adds the place-based component that is critical to sustainability science while revealing how science impacts students' everyday lives. Experience in addressing realistic, real-life problems fosters the habits of mind necessary to address these problems and instills a sense of social and political efficacy and responsibility. The L(SC)2 course paradigm employs a variety of educational tools (active problem-based learning, collaborative work, peer instruction, interdisciplinarity, and global context-based instruction) that improve lasting comprehension by creating a more effective learning environment. In this paradigm, STEM students learn that although there may be a technically or scientifically optimal solution to a problem, it must be responsive to a society's social, legal, cultural and religious parameters. Conversely, students in non-STEM fields learn that solutions to societal problems must be scientifically valid and technologically feasible. The interaction of STEM and non-STEM students in L(SC)2 courses builds bridges between the natural and social sciences that are critical for a successful sustainability transition and lacking in most traditional science courses.

  20. Morphological, Micoscopical Studies and Elemental analysis of Polygonum Chinese L. and Rhoeo discolor Hance

    International Nuclear Information System (INIS)

    Moe Moe Lwin

    2008-03-01

    In the present study, two selected medicinal plants, namely Polygonum chinense L. (Mahaga-Kyansit) and Rhoeo discolor Hance. (Mi-gwin-gamon) are collected from Dawei District. In this paper, the outstanding features of selected plants, microscopical characters and elemental analysis of these leaves are also presented.In morphological studies of Mahaga-kyansit, herbs, swollen at nodes, black-coloured patches present at central portion of leaf blade, ochreate stipules. The inflorescences are terminally corymbose. The ovary trigonous-ovoid, stigma trifixed. In microscopical studies, stomata anomocytic. The cuticle is striation on both surface. In transverse section of midrib, the vascular bundles are collateral, about 8-10 numbers in basal, one was larger than the other bundles, 2numbers in middle regions and 1 bundle in apical regions. Calcium oxalate crystals (Rosette) are present in the parenchymatous cells. In the present study, the Migwin-gamon are rosette-forming succulent herbs. The leaves are crowded, upright, the upper surface green, the lower surface rich reddish-purple. The inflorescences are axillary, boat-shaped. Flowers involucres bracts. The androecium are stamens 6, often clothed wIth moniliform hairs, anthers often with and expanded or variously modified connective. The gynaecium are carpel 3,, trilocular, stigma capitate. In the microscopical studies, the leaves are isobilateral leaf. The stomata are tetracytic type. Lower epidermis cells larger than the upper one and stoma in the lower epidermis. Crystal of tetragonal system form (Prism) present in the mesophyll cells.

  1. Renal Morphology, Clinical Findings, and Progression Rate in Mesoamerican Nephropathy.

    Science.gov (United States)

    Wijkström, Julia; González-Quiroz, Marvin; Hernandez, Mario; Trujillo, Zulma; Hultenby, Kjell; Ring, Anneli; Söderberg, Magnus; Aragón, Aurora; Elinder, Carl-Gustaf; Wernerson, Annika

    2017-05-01

    Mesoamerican nephropathy (MeN) is a chronic kidney disease affecting rural inhabitants in Central America. We have previously described the renal morphology in 8 patients from El Salvador. To confirm the renal pathology, we have studied kidney biopsies from patients with MeN in Nicaragua. Follow-up urine and blood samples from both biopsy studies were collected to investigate the natural history. Case series. In the kidney biopsy study, 19 male sugarcane workers in Nicaragua with suspected MeN were investigated with questionnaires, kidney biopsies, and blood and urine analysis. Inclusion criteria were age 20 to 65 years and plasma creatinine level of 1.13 to 2.49mg/dL or estimated glomerular filtration rate (eGFR) of 30 to 80mL/min/1.73m 2 . Exclusion criteria were proteinuria with protein excretion > 3g/24 h, uncontrolled hypertension, diabetes mellitus, or other known kidney disease. In the follow up-study, blood and urine from the kidney biopsy study in Nicaragua (n=18) and our previous biopsy study of MeN cases in El Salvador (n=7) were collected 1 to 1.5 and 2 to 2.5 years after biopsy, respectively. Renal morphology, clinical, and biochemical characteristics, change in eGFR per year. eGFR was calculated using the CKD-EPI creatinine (eGFR cr ), cystatin C (eGFR cys ), and creatinine-cystatin C (eGFR cr-cys ) equations. In the kidney biopsy study, participants had a mean eGFR cr of 57 (range, 33-96) mL/min/1.73m 2 . 47% had low plasma sodium and 21% had low plasma potassium levels. 16 kidney biopsies were representative and showed glomerulosclerosis (mean, 38%), glomerular hypertrophy, and signs of chronic glomerular ischemia. Mild to moderate tubulointerstitial damage and mostly mild vascular changes were seen. In the follow up-study, median duration of follow-up was 13 (range, 13-27) months. Mean change in eGFR cr was -4.4±8.4 (range, -27.7 to 10.2) mL/min/1.73m 2 per year. Most patients had stopped working with sugarcane cultivation. 3 biopsy specimens

  2. Second Language Word Learning through Repetition and Imitation: Functional Networks as a Function of Learning Phase and Language Distance.

    Science.gov (United States)

    Ghazi-Saidi, Ladan; Ansaldo, Ana Ines

    2017-01-01

    Introduction and Aim : Repetition and imitation are among the oldest second language (L2) teaching approaches and are frequently used in the context of L2 learning and language therapy, despite some heavy criticism. Current neuroimaging techniques allow the neural mechanisms underlying repetition and imitation to be examined. This fMRI study examines the influence of verbal repetition and imitation on network configuration. Integration changes within and between the cognitive control and language networks were studied, in a pair of linguistically close languages (Spanish and French), and compared to our previous work on a distant language pair (Ghazi-Saidi et al., 2013). Methods : Twelve healthy native Spanish-speaking (L1) adults, and 12 healthy native Persian-speaking adults learned 130 new French (L2) words, through a computerized audiovisual repetition and imitation program. The program presented colored photos of objects. Participants were instructed to look at each photo and pronounce its name as closely as possible to the native template (imitate). Repetition was encouraged as many times as necessary to learn the object's name; phonological cues were provided if necessary. Participants practiced for 15 min, over 30 days, and were tested while naming the same items during fMRI scanning, at week 1 (shallow learning phase) and week 4 (consolidation phase) of training. To compare this set of data with our previous work on Persian speakers, a similar data analysis plan including accuracy rates (AR), response times (RT), and functional integration values for the language and cognitive control network at each measure point was included, with further L1-L2 direct comparisons across the two populations. Results and Discussion : The evidence shows that learning L2 words through repetition induces neuroplasticity at the network level. Specifically, L2 word learners showed increased network integration after 3 weeks of training, with both close and distant language

  3. Vertebral body bone strength: the contribution of individual trabecular element morphology.

    Science.gov (United States)

    Parkinson, I H; Badiei, A; Stauber, M; Codrington, J; Müller, R; Fazzalari, N L

    2012-07-01

    Although the amount of bone explains the largest amount of variability in bone strength, there is still a significant proportion unaccounted for. The morphology of individual bone trabeculae explains a further proportion of the variability in bone strength and bone elements that contribute to bone strength depending on the direction of loading. Micro-CT imaging enables measurement of bone microarchitecture and subsequently mechanical strength of the same sample. It is possible using micro-CT data to perform morphometric analysis on individual rod and plate bone trabeculae using a volumetric spatial decomposition algorithm and hence determine their contribution to bone strength. Twelve pairs of vertebral bodies (T12/L1 or L4/L5) were harvested from human cadavers, and bone cubes (10 × 10 × 10 mm) were obtained. After micro-CT imaging, a volumetric spatial decomposition algorithm was applied, and measures of individual trabecular elements were obtained. Bone strength was measured in compression, where one bone specimen from each vertebral segment was tested supero-inferiorly (SI) and the paired specimen was tested antero-posteriorly (AP). Bone volume fraction was the strongest individual determinant of SI strength (r(2) = 0.77, p body bone architecture into its constituent morphological elements shows that trabecular element morphology has specific functional roles to assist in maintaining skeletal integrity.

  4. β-L-Arabinofuranosylation Conducted by 5-O-(2-pyridinecarbonyl)-L-arabinofuranosyl Trichloroacetimidate.

    Science.gov (United States)

    Li, Hong-Zhan; Ding, Jie; Cheng, Chun-Ru; Chen, Yue; Liang, Xing-Yong

    2018-05-02

    We describe a β-L-arabinofuranosylation method by employing the 5-O-(2-pyridinecarbonyl)-L-arabinofuranosyl trichloroacetimidate 10 as a donor. This approach allows a wide range of acceptor substrates, especially amino acid acceptors, to be used. Stereoselective synthesis of β-(1,4)-L-arabinofuranosyl-(2S, 4R)-4-hydroxy-L-proline (β-L-Araf-L-Hyp 4 ) and its dimer is achieved readily by this method. Both the stereoselectivities and yields of the reactions are excellent. To demonstrate the utility of this methodology, the preparation of a trisaccharide in a one-pot manner was carried out. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Semantic and phonological schema influence spoken word learning and overnight consolidation.

    Science.gov (United States)

    Havas, Viktória; Taylor, Jsh; Vaquero, Lucía; de Diego-Balaguer, Ruth; Rodríguez-Fornells, Antoni; Davis, Matthew H

    2018-06-01

    We studied the initial acquisition and overnight consolidation of new spoken words that resemble words in the native language (L1) or in an unfamiliar, non-native language (L2). Spanish-speaking participants learned the spoken forms of novel words in their native language (Spanish) or in a different language (Hungarian), which were paired with pictures of familiar or unfamiliar objects, or no picture. We thereby assessed, in a factorial way, the impact of existing knowledge (schema) on word learning by manipulating both semantic (familiar vs unfamiliar objects) and phonological (L1- vs L2-like novel words) familiarity. Participants were trained and tested with a 12-hr intervening period that included overnight sleep or daytime awake. Our results showed (1) benefits of sleep to recognition memory that were greater for words with L2-like phonology and (2) that learned associations with familiar but not unfamiliar pictures enhanced recognition memory for novel words. Implications for complementary systems accounts of word learning are discussed.

  6. Low dose CT reconstruction via L1 norm dictionary learning using alternating minimization algorithm and balancing principle.

    Science.gov (United States)

    Wu, Junfeng; Dai, Fang; Hu, Gang; Mou, Xuanqin

    2018-04-18

    Excessive radiation exposure in computed tomography (CT) scans increases the chance of developing cancer and has become a major clinical concern. Recently, statistical iterative reconstruction (SIR) with l0-norm dictionary learning regularization has been developed to reconstruct CT images from the low dose and few-view dataset in order to reduce radiation dose. Nonetheless, the sparse regularization term adopted in this approach is l0-norm, which cannot guarantee the global convergence of the proposed algorithm. To address this problem, in this study we introduced the l1-norm dictionary learning penalty into SIR framework for low dose CT image reconstruction, and developed an alternating minimization algorithm to minimize the associated objective function, which transforms CT image reconstruction problem into a sparse coding subproblem and an image updating subproblem. During the image updating process, an efficient model function approach based on balancing principle is applied to choose the regularization parameters. The proposed alternating minimization algorithm was evaluated first using real projection data of a sheep lung CT perfusion and then using numerical simulation based on sheep lung CT image and chest image. Both visual assessment and quantitative comparison using terms of root mean square error (RMSE) and structural similarity (SSIM) index demonstrated that the new image reconstruction algorithm yielded similar performance with l0-norm dictionary learning penalty and outperformed the conventional filtered backprojection (FBP) and total variation (TV) minimization algorithms.

  7. THE SELF-CORRECTION OF ENGLISH SPEECH ERRORS IN SECOND LANGUANGE LEARNING

    Directory of Open Access Journals (Sweden)

    Ketut Santi Indriani

    2015-05-01

    Full Text Available The process of second language (L2 learning is strongly influenced by the factors of error reconstruction that occur when the language is learned. Errors will definitely appear in the learning process. However, errors can be used as a step to accelerate the process of understanding the language. Doing self-correction (with or without giving cues is one of the examples. In the aspect of speaking, self-correction is done immediately after the error appears. This study is aimed at finding (i what speech errors the L2 speakers are able to identify, (ii of the errors identified, what speech errors the L2 speakers are able to self correct and (iii whether the self-correction of speech error are able to immediately improve the L2 learning. Based on the data analysis, it was found that the majority identified errors are related to noun (plurality, subject-verb agreement, grammatical structure and pronunciation.. B2 speakers tend to correct errors properly. Of the 78% identified speech errors, as much as 66% errors could be self-corrected accurately by the L2 speakers. Based on the analysis, it was also found that self-correction is able to improve L2 learning ability directly. This is evidenced by the absence of repetition of the same error after the error had been corrected.

  8. Using Mixed-Modality Learning Strategies via e-Learning for Second Language Vocabulary Acquisition

    Science.gov (United States)

    Yang, Fang-Chuan Ou; Wu, Wen-Chi Vivian

    2015-01-01

    This study demonstrated an e-learning system, MyEVA, based on a mixed-modality vocabulary strategy in assisting learners of English as a second language (L2 learners) to improve their vocabulary. To explore the learning effectiveness of MyEVA, the study compared four vocabulary-learning techniques, MyEVA in preference mode, MyEVA in basic mode, an…

  9. Salience in Second Language Acquisition:Physical form, learner attention, and instructional focus

    Directory of Open Access Journals (Sweden)

    Myrna C Cintrón-Valentín

    2016-08-01

    Full Text Available We consider the role of physical form, prior experience, and form focused instruction (FFI in adult language learning. (1 When presented with competing cues to interpretation, learners are more likely to attend to physically more salient cues in the input. (2 Learned attention is an associative learning phenomenon where prior-learned cues block those that are experienced later. (3 The low salience of morphosyntactic cues can be overcome by FFI, which leads learners to attend cues which might otherwise be ignored. Experiment 1 used eye-tracking to investigate how language background influences learners’ attention to morphological cues, as well as the attentional processes whereby different types of FFI overcome low cue salience, learned attention and blocking. Chinese native speakers (no L1 verb-tense morphology viewed Latin utterances combining lexical and morphological cues to temporality under control conditions (CC and three types of explicit FFI: grammar instruction (VG, verb salience with textual enhancement (VS, and verb pretraining (VP, and their use of these cues was assessed in a comprehension test. CC participants were significantly more sensitive to the adverbs than verb morphology. Instructed participants showed greater sensitivity to the verbs. These results reveal attentional processes whereby learners’ prior linguistic experience can shape their attention toward cues in the input, and whereby FFI helps learners overcome the long-term blocking of verb-tense morphology. Experiment 2 examined the role of modality of input presentation – aural or visual – in L1 English learners’ attentional focus on morphological cues and the effectiveness of different FFI manipulations. CC participants showed greater sensitivity toward the adverb cue. FFI was effective in increasing attention to verb-tense morphology, however, the processing of morphological cues was considerably more difficult under aural presentation. From visual exposure

  10. CO2 and temperature effects on morphological and physiological traits affecting risk of drought-induced mortality.

    Science.gov (United States)

    Duan, Honglang; Chaszar, Brian; Lewis, James D; Smith, Renee A; Huxman, Travis E; Tissue, David T

    2018-04-26

    Despite a wealth of eco-physiological assessments of plant response to extreme drought, few studies have addressed the interactive effects of global change factors on traits driving mortality. To understand the interaction between hydraulic and carbon metabolic traits influencing tree mortality, which may be independently influenced by atmospheric [CO2] and temperature, we grew Eucalyptus sideroxylon A. Cunn. ex Woolls from seed in a full-factorial [CO2] (280, 400 and 640 μmol mol-1, Cp, Ca and Ce, respectively) and temperature (ambient and ambient +4 °C, Ta and Te, respectively) experiment. Prior to drought, growth across treatment combinations resulted in significant variation in physiological and morphological traits, including photosynthesis (Asat), respiration (Rd), stomatal conductance, carbohydrate storage, biomass and leaf area (LA). Ce increased Asat, LA and leaf carbohydrate concentration compared with Ca, while Cp generated the opposite response; Te reduced Rd. However, upon imposition of drought, Te hastened mortality (9 days sooner compared with Ta), while Ce significantly exacerbated drought stress when combined with Te. Across treatments, earlier time-to-mortality was mainly associated with lower (more negative) leaf water potential (Ψl) during the initial drought phase, along with higher water loss across the first 3 weeks of water limitation. Among many variables, Ψl was more important than carbon status in predicting time-to-mortality across treatments, yet leaf starch was associated with residual variation within treatments. These results highlight the need to carefully consider the integration, interaction and hierarchy of traits contributing to mortality, along with their responses to environmental drivers. Both morphological traits, which influence soil resource extraction, and physiological traits, which affect water-for-carbon exchange to the atmosphere, must be considered to adequately predict plant response to drought. Researchers have

  11. A novel mechanism of RNase L inhibition: Theiler's virus L* protein prevents 2-5A from binding to RNase L

    Science.gov (United States)

    Drappier, Melissa; Elliott, Ruth; Zhang, Rong; Weiss, Susan R.; Silverman, Robert H.

    2018-01-01

    The OAS/RNase L pathway is one of the best-characterized effector pathways of the IFN antiviral response. It inhibits the replication of many viruses and ultimately promotes apoptosis of infected cells, contributing to the control of virus spread. However, viruses have evolved a range of escape strategies that act against different steps in the pathway. Here we unraveled a novel escape strategy involving Theiler’s murine encephalomyelitis virus (TMEV) L* protein. Previously we found that L* was the first viral protein binding directly RNase L. Our current data show that L* binds the ankyrin repeats R1 and R2 of RNase L and inhibits 2’-5’ oligoadenylates (2-5A) binding to RNase L. Thereby, L* prevents dimerization and oligomerization of RNase L in response to 2-5A. Using chimeric mouse hepatitis virus (MHV) expressing TMEV L*, we showed that L* efficiently inhibits RNase L in vivo. Interestingly, those data show that L* can functionally substitute for the MHV-encoded phosphodiesterase ns2, which acts upstream of L* in the OAS/RNase L pathway, by degrading 2-5A. PMID:29652922

  12. Polycystic ovary morphology: age-based ultrasound criteria.

    Science.gov (United States)

    Kim, Hyun-Jun; Adams, Judith M; Gudmundsson, Jens A; Arason, Gudmundur; Pau, Cindy T; Welt, Corrine K

    2017-09-01

    To determine age-based criteria for polycystic ovary morphology. Cross-sectional, case-control design. Outpatient setting. Women with polycystic ovary syndrome (PCOS) defined by hyperandrogenism and irregular menses (n = 544) and controls with regular menses and no evidence of hyperandrogenism (n = 666) participated. Parameters were tested in a second cohort of women with PCOS (n = 105) and controls (n = 32) meeting the same criteria. Subjects underwent a pelvic ultrasound documenting ovarian volume and maximum follicle number in a single plane. A receiver operating characteristic curve was constructed to determine the ovarian volume and follicle number with the best sensitivity and specificity to define PCOS for age groups at approximately 5-year intervals from age 18 to >44 years. The best sensitivity and specificity were obtained using a threshold volume of 12 mL and 13 follicles for ages ≤24 years, 10 mL and 14 follicles for ages 25-29 years, 9 mL and 10 follicles for ages 30-34 years, 8 mL and 10 follicles for ages 35-39 years, 10 mL and 9 follicles for ages 40-44 years, and 6 mL and 7 follicles for ages >44 years. Data from a second cohort confirmed the need to decrease volume and follicle number with increasing age to diagnose PCOS. Polycystic ovary morphology was most accurate at predicting the PCOS diagnosis for women ages 30-39 years. The ovarian volume and follicle number threshold to define polycystic ovary morphology should be lowered starting at age 30. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Restoration of compact Golgi morphology in advanced prostate cancer enhances susceptibility to galectin-1-induced apoptosis by modifying mucin O-glycan synthesis.

    Science.gov (United States)

    Petrosyan, Armen; Holzapfel, Melissa S; Muirhead, David E; Cheng, Pi-Wan

    2014-12-01

    Prostate cancer progression is associated with upregulation of sialyl-T antigen produced by β-galactoside α-2,3-sialyltransferase-1 (ST3Gal1) but not with core 2-associated polylactosamine despite expression of core 2 N-acetylglucosaminyltransferase-L (C2GnT-L/GCNT1). This property allows androgen-refractory prostate cancer cells to evade galectin-1 (LGALS1)-induced apoptosis, but the mechanism is not known. We have recently reported that Golgi targeting of glycosyltransferases is mediated by golgins: giantin (GOLGB1) for C2GnT-M (GCNT3) and GM130 (GOLGA2)-GRASP65 (GORASP1) or GM130-giantin for core 1 synthase. Here, we show that for Golgi targeting, C2GnT-L also uses giantin exclusively whereas ST3Gal1 uses either giantin or GM130-GRASP65. In addition, the compact Golgi morphology is detected in both androgen-sensitive prostate cancer and normal prostate cells, but fragmented Golgi and mislocalization of C2GnT-L are found in androgen-refractory cells as well as primary prostate tumors (Gleason grade 2-4). Furthermore, failure of giantin monomers to be phosphorylated and dimerized prevents Golgi from forming compact morphology and C2GnT-L from targeting the Golgi. On the other hand, ST3Gal1 reaches the Golgi by an alternate site, GM130-GRASP65. Interestingly, inhibition or knockdown of non-muscle myosin IIA (MYH9) motor protein frees up Rab6a GTPase to promote phosphorylation of giantin by polo-like kinase 3 (PLK3), which is followed by dimerization of giantin assisted by protein disulfide isomerase A3 (PDIA3), and restoration of compact Golgi morphology and targeting of C2GnT-L. Finally, the Golgi relocation of C2GnT-L in androgen-refractory cells results in their increased susceptibility to galectin-1-induced apoptosis by replacing sialyl-T antigen with polylactosamine. This study demonstrates the importance of Golgi morphology and regulation of glycosylation and provides insight into how the Golgi influences cancer progression and metastasis. ©2014 American

  14. Contributions of Letter-Speech Sound Learning and Visual Print Tuning to Reading Improvement: Evidence from Brain Potential and Dyslexia Training Studies

    Directory of Open Access Journals (Sweden)

    Gorka Fraga González

    2017-01-01

    Full Text Available We use a neurocognitive perspective to discuss the contribution of learning letter-speech sound (L-SS associations and visual specialization in the initial phases of reading in dyslexic children. We review findings from associative learning studies on related cognitive skills important for establishing and consolidating L-SS associations. Then we review brain potential studies, including our own, that yielded two markers associated with reading fluency. Here we show that the marker related to visual specialization (N170 predicts word and pseudoword reading fluency in children who received additional practice in the processing of morphological word structure. Conversely, L-SS integration (indexed by mismatch negativity (MMN may only remain important when direct orthography to semantic conversion is not possible, such as in pseudoword reading. In addition, the correlation between these two markers supports the notion that multisensory integration facilitates visual specialization. Finally, we review the role of implicit learning and executive functions in audiovisual learning in dyslexia. Implications for remedial research are discussed and suggestions for future studies are presented.

  15. A real-time articulatory visual feedback approach with target presentation for second language pronunciation learning.

    Science.gov (United States)

    Suemitsu, Atsuo; Dang, Jianwu; Ito, Takayuki; Tiede, Mark

    2015-10-01

    Articulatory information can support learning or remediating pronunciation of a second language (L2). This paper describes an electromagnetic articulometer-based visual-feedback approach using an articulatory target presented in real-time to facilitate L2 pronunciation learning. This approach trains learners to adjust articulatory positions to match targets for a L2 vowel estimated from productions of vowels that overlap in both L1 and L2. Training of Japanese learners for the American English vowel /æ/ that included visual training improved its pronunciation regardless of whether audio training was also included. Articulatory visual feedback is shown to be an effective method for facilitating L2 pronunciation learning.

  16. Integrating E-Learning 2.0 into Online Courses

    Science.gov (United States)

    Yuen, Steve Chi-Yin

    2014-01-01

    This paper provides an overview of e-learning 2.0 concepts and presents a case study that involves the design, development, and teaching of two online courses based on e-learning 2.0 concepts. The design and the construction of e-learning 2.0 courses, and their effects on the students' learning experience are examined. In addition, students'…

  17. Distortion of He(2l2l') Fano lineshapes by strong post-collision interaction in H+-He collisions

    International Nuclear Information System (INIS)

    Moretto-Capelle, P.; Benhenni, M.; Bordenave-Montesquieu, D.; Bordenave-Montesquieu, A.

    1996-01-01

    The three-body post-collisional interaction (PCI) between the scattered proton, recoil target ion and emitted electron has been investigated by electron spectrometry near the 2l2l' helium resonances, in the 20-100 keV energy range (V p 0.9-2 au). Particular attention has been paid to the PCI deformations of the Fano lineshapes when V-vector'' p ≅ V-vector e (2l2l'). Their angle and collision velocity dependences have been studied for the first time experimentally. A large variety of lineshapes have been observed, all of them successfully described by a single formula. At the lowest proton velocities the rescattering effect (also called Coulomb two-path scattering) is seen. (Author)

  18. Lessons Learned from Native C.I.R.C.L.E., a Culturally Specific Resource.

    Science.gov (United States)

    Garcia, Andrea; Baethke, Lisa; Kaur, Judith S

    2017-12-01

    Cancer is now the second leading cause of death among American Indians and Alaska Natives (AIAN), and trends in cancer-related mortality over the past 2 decades show inferior control in AIAN compared to non-Hispanic Whites. The American Indian/Alaska Native Cancer Information Resource Center and Learning Exchange (Native C.I.R.C.L.E.) was developed in the year 2000 as part of a comprehensive network of partnerships to develop, maintain, and disseminate culturally appropriate cancer and other health information materials for AIAN educators and providers. Now, in its 15th year of existence, enough data has been accumulated by Native C.I.R.C.L.E. to analyze trends in the distribution of culturally relevant cancer information materials and compare access to both printed (hard copy) and online materials. The amount of culturally appropriate materials available since its creation has increased more than 10-fold. Print materials are now distributed throughout the world, and the number of materials requested from print and downloads combined are in the thousands on a monthly basis. Native C.I.R.C.L.E. is in the process of expanding its access and capabilities to target more of the lay AIAN public in order to address the digital divide.

  19. Screening of sesame ecotypes (Sesamum indicum L. for salinity tolerance under field conditions: 1-Phenological and morphological characteristics

    Directory of Open Access Journals (Sweden)

    F. Fazeli Kakhki

    2016-05-01

    Full Text Available Salinity is one of the most restrictions in plant growth in dry and semi dry land which effects production of many crops such as sesame. In order to study the phenology and morphology characteristics of 43 ecotypes and line of sesame (Sesamum indicum L. under salinity of irrigation water (5.2 dS.m-1 a field experiment was conducted at research farm of center of excellence for special crops, Ferdowsi University of Mashhad, Iran, during growing season of 2009-2010 based on a randomized complete block design with three replications. Results showed that four sesame ecotypes could not emerge, 14 sesame ecotypes had appropriate emergence but died before reproductive stage and only 58 % of sesame ecotypes could alive until maturity. There was significant difference between sesame ecotypes for phenological stages and were varied from 64 to 81 days for vegetative and 60 to 65 days for reproductive stages. Plant height, number and length of branches also were different between sesame ecotypes. The highest and the lowest plant height were observed in MSC43 and MSC12 ecotypes, respectively. Number of branches per plant was from 1 to 8 and length of branches in 32 percent of ecotypes was more than 100 cm. There was a considerable correlation between seed weight in plant with reproductive growth (r=0.38** and plant height (r=0.25. In addition different response of sesame ecotypes to saline water and also better morphological indices in some sesame ecotypes may be show the tolerance of these accessions to salinity. More studies may be useful for selection of sesame salt tolerance resources.

  20. A model of the effect of uncertainty on the C elegans L2/L2d decision.

    Directory of Open Access Journals (Sweden)

    Leon Avery

    Full Text Available At the end of the first larval stage, the C elegans larva chooses between two developmental pathways, an L2 committed to reproductive development and an L2d, which has the option of undergoing reproductive development or entering the dauer diapause. I develop a quantitative model of this choice using mathematical tools developed for pricing financial options. The model predicts that the optimal decision must take into account not only the expected potential for reproductive growth, but also the uncertainty in that expected potential. Because the L2d has more flexibility than the L2, it is favored in unpredictable environments. I estimate that the ability to take uncertainty into account may increase reproductive value by as much as 5%, and discuss possible experimental tests for this ability.

  1. Morphological parameters for implantation of the screwless spring loop dynamic posterior spinous process stabilizing system.

    Science.gov (United States)

    Song, Geun Soo; Lee, Yeon Soo

    2015-07-01

    This study aimed to quantify morphological characteristics of the posterior lumbar spinous process, which may affect stable implantation of screwless wire spring loops. Virtual implantations of a screwless wire spring loop onto pairs of lumbar spinous processes were performed for computed tomography (CT)-derived three-dimensional vertebral models of 40 Korean subjects. Morphological parameters of lumbar vertebrae 1 through 5 (L1-L5) were measured with regard to bone-implant interference. In males, the transspinous process fixation lengths decreased from 57.8±3.0mm to 48.8±3.2mm as the lumbar joints descend from L1-L2 to L4-L5, with those in females about 4.1±0.4mm shorter (pprocess and the greatest (8.1±2.2mm) for the L4 upper spinous process; this was 1.0±10.3mm less than that for males at corresponding levels (p>0.05). The ratio of the spinous process clenched thickness to the transspinous fixation length increased from 0.133±0.016 to 0.196±0.076 for the upper spinous processes as the lumbar joints descend. The ratio of the spinous process clenched thickness to the transspinous fixation length varies, depending on gender and whether the clenched level is the upper or lower spinous process. These parameters related to the clenching fixation stability should be considered in development and implantations of the screwless wire spring loop. Copyright © 2015 Elsevier GmbH. All rights reserved.

  2. Localization of Rod Bipolar Cells in the Mammalian Retina Using an Antibody Against the α1c L-type Ca2+ Channel

    International Nuclear Information System (INIS)

    Huh, Yu-Jin; Choi, Jae-Sik; Jeon, Chang-Jin

    2015-01-01

    Bipolar cells transmit stimuli via graded changes in membrane potential and neurotransmitter release is modulated by Ca 2+ influx through L-type Ca 2+ channels. The purpose of this study was to determine whether the α 1 c subunit of L-type voltage-gated Ca 2+ channel (α 1 c L-type Ca 2+ channel) colocalizes with protein kinase C alpha (PKC-α), which labels rod bipolar cells. Retinal whole mounts and vertical sections from mouse, hamster, rabbit, and dog were immunolabeled with antibodies against PKC-α and α 1 c L-type Ca 2+ channel, using fluorescein isothiocyanate (FITC) and Cy5 as visualizing agents. PKC-α-immunoreactive cells were morphologically identical to rod bipolar cells as previously reported. Their cell bodies were located within the inner nuclear layer, dendritic processes branched into the outer plexiform layer, and axons extended into the inner plexiform layer. Immunostaining showed that α 1 c L-type Ca 2+ channel colocalized with PKC-α in rod bipolar cells. The identical expression of PKC-α and α 1 c L-type Ca 2+ channel indicates that the α 1 c L-type Ca 2+ channel has a specific role in rod bipolar cells, and the antibody against the α 1 c L-type Ca 2+ channel may be a useful marker for studying the distribution of rod bipolar cells in mouse, hamster, rabbit, and dog retinas

  3. A L2HGDH initiator methionine codon mutation in a Yorkshire terrier with L-2-hydroxyglutaric aciduria

    Directory of Open Access Journals (Sweden)

    Farias Fabiana HG

    2012-07-01

    Full Text Available Abstract Background L-2-hydroxyglutaric aciduria is a metabolic repair deficiency characterized by elevated levels of L-2-hydroxyglutaric acid in urine, blood and cerebrospinal fluid. Neurological signs associated with the disease in humans and dogs include seizures, ataxia and dementia. Case presentation Here we describe an 8 month old Yorkshire terrier that presented with episodes of hyperactivity and aggressive behavior. Between episodes, the dog’s behavior and neurologic examinations were normal. A T2 weighted MRI of the brain showed diffuse grey matter hyperintensity and a urine metabolite screen showed elevated 2-hydroxyglutaric acid. We sequenced all 10 exons and intron-exon borders of L2HGDH from the affected dog and identified a homozygous A to G transition in the initiator methionine codon. The first inframe methionine is at p.M183 which is past the mitochondrial targeting domain of the protein. Initiation of translation at p.M183 would encode an N-terminal truncated protein unlikely to be functional. Conclusions We have identified a mutation in the initiation codon of L2HGDH that is likely to result in a non-functional gene. The Yorkshire terrier could serve as an animal model to understand the pathogenesis of L-2-hydroxyglutaric aciduria and to evaluate potential therapies.

  4. LearnWeb 2.0. Integrating Social Software for Lifelong Learning.

    NARCIS (Netherlands)

    Marenzi, Ivana; Demidova, Elena; Nejdl, Wolfgang

    2008-01-01

    Marenzi, I., Demidova, E., & Nejdl, W. (2008). LearnWeb 2.0. Integrating Social Software for Lifelong Learning. Proceedings of the ED-Media 2008. World Conference on Educational Multimedia, Hypermedia & Telecommunications. June, 30 - July, 4, 2008, Austria, Vienna.

  5. L.S. Vygotsky's Principle "One Step in Learning — A Hundred Steps in Development": In Search of Evidence

    Directory of Open Access Journals (Sweden)

    V.K. Zaretsky

    2015-10-01

    Full Text Available On the basis of L.S. Vygotsky's published works the paper attempts to trace the dynamics of his concepts of child development and to provide evidence supporting Vygotsky's statement that one step in learning equals a hundred in development, which is one of the key principles of culturalhistorical theory in its application to child development. This statement is put in a row with two other major principles: one arguing that learning precedes development and the other referring to the zone of proximal development. The paper outlines a multivector model of the zone of proximal development as one of the conceptual tools of the reflective and activity approach to helping children overcome learning difficulties and promoting their development. The paper also describes a case study in which an orphan child with a disability received psychological and educational support that obviously contributed to the child's development. It is argued that L.S. Vygotsky's idea of the specific relationship between learning and development has fundamental theoretical and practical implications, in particular, for working with children with special needs

  6. The Effect of Stereoscopic ("3D") vs. 2D Presentation on Learning through Video and Film

    Science.gov (United States)

    Price, Aaron; Kasal, E.

    2014-01-01

    Two Eyes, 3D is a NSF-funded research project into the effects of stereoscopy on learning of highly spatial concepts. We report final results on one study of the project which tested the effect of stereoscopic presentation on learning outcomes of two short films about Type 1a supernovae and the morphology of the Milky Way. 986 adults watched either film, randomly distributed between stereoscopic and 2D presentation. They took a pre-test and post-test that included multiple choice and drawing tasks related to the spatial nature of the topics in the film. Orientation of the answering device was also tracked and a spatial cognition pre-test was given to control for prior spatial ability. Data collection took place at the Adler Planetarium's Space Visualization Lab and the project is run through the AAVSO.

  7. Morphological evaluation of lumbar dorsal root ganglion on three-dimensional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Shen Jun; Chen Jianyu; Zhou Cuiping; Liang Biling; Xu Xiaomao

    2007-01-01

    Objective: To investigate the morphological features of normal lumbar dorsal root ganglia using a three-dimensional (3D) coronal MR imaging. Methods: One hundred and fifteen volunteers were included. Ages ranged from 15 to 75 years, with a mean of 40 years. Coronal 3D fast field echo (FFE) with water selective excitation (Proset) MR examination of 1150 dorsal root ganglia were underwent at nerve root levels from L1 to L5. The source coronal images were further reconstructed into a series of rotational alignment coronal images with an interval angel of 12 degree using maximum intensity projection (MIP) technique. All DRGs of bilateral spinal nerve from L1 to L5 were morphologically analyzed on the original and MIP images including qualitative evaluation of the location, signal intensity, architecture and quantitative dimensional measurement. Results: There were 225, 225, 219, 210 and 160 foraminal ganglia from L1 to L5 level, respectively. The incidence of intraspinal ganglia from L3 to L5 gradually increased with a maximum at L5 level of 29.1% (X 2 =188.371, P<0.01). One thousand one hundred and thirteen (96.8%) DRGs were intermediate intensity on MIP images. The width and length of L1 DRGs were from 2. 00 to 5.50 mm (3.38±0.77) mm, 2.00 to 7.00 mm (4.35±0.89) mm, respectively. The width and length of L5 DRGs were from 3.50 to 9.00 mm (6.40±0.91) mm, 6.00 to 19.00 mm [(11.58± 2.25) mm], respectively. There was statistically significant difference in the dimension of DRGs from L5 to L1 (F=41.527-205.998, P<0.01). In 1150 DRGs, three types of architecture of DRGs including 822 singular, 317 bi- and 11 tri-ganglion DRGs could be found with a high prevalence of the bi-ganglia in L4 and L3 DRGs and a higher incidence of the singular ganglia in the L5 and L2 and L1 DRGs. Conclusions: The normal anatomy and variant of the lumbar dorsal root ganglia could be clearly demonstrated by 3D FFE MR imaging with Proset. As the level of the nerve root traveled down caudally

  8. Children's Implicit Learning of Graphotactic and Morphological Regularities

    Science.gov (United States)

    Pacton, Sbastien; Fayol, Michel; Perruchet, Pierre

    2005-01-01

    In French, the transcription of the same sound can be guided by both probabilistic graphotactic constraints (e.g., t is more often transcribed ette after -v than after -f) and morphological constraints (e.g., t is always transcribed ette when used as a diminutive suffix). Three experiments showed that pseudo-word spellings of 8-to 11-year-old…

  9. Defense AT&L Magazine A Publication of the Defense Acquisition University. Volume 34, Number 2, DAU 183

    National Research Council Canada - National Science Library

    Turk, Wayne; Wynn, Michael W; Schaeffer, Mark D; Walsh, John; Kratz, Louise A; Ward, Dan; Brown, David; McVay, Tammi

    2005-01-01

    .... As the flagship publication of the Defense Acquisition University, Defense AT AND L also disseminates information on training and education, continuous learning, and e-Learning to those acquisition...

  10. A comparative study on surface morphology from the HgI2 semiconductors prepared by different techniques

    International Nuclear Information System (INIS)

    Martins, Joao F.T.; Ferraz, Caue de M.; Santos, Robinson A. dos; Mesquita, Carlos H. de; Hamada, Margarida M.

    2013-01-01

    The impurity effect in the surface morphology quality of HgI 2 crystals was evaluated, aiming a future application of these crystals as room temperature radiation semiconductor detector. The crystals were purified and grown by two techniques: (1) physical vapor transport (PVT) and (2) saturated solution from dimethylsulfoxide (DMSO) complexes. Systematic measurements were carried out for determining the stoichiometry, structure orientation, surface morphology and impurity of the crystal. The best quality of surface morphology was found for the crystals purified and grown by the PVT technique. Significant decrease in the impurity concentration was found, purifying the crystal by means of two successive growths by the PVT technique, while a Si contamination in the HgI 2 crystal was observed, during its growth by the DMSO method. Thus, for DMSO technique was not possible to identify the peaks of the other trace elements present as impurities in the PVT crystal, due to the high intensity of the Si peak in the DMSO crystal. It was demonstrated the impurities affect significantly the surface morphology quality from the HgI 2 crystal. Key Words: Semiconductor crystal, Radiation detector, Mercury Iodide crystal, surface morphology. (author)

  11. Analysis list: Ash2l [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Ash2l Blood + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2l.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2l.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2...l.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Ash2l.Blood.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Blood.gml ...

  12. The morphology of Ganoderma lucidum mycelium in a repeated-batch fermentation for exopolysaccharide production

    Directory of Open Access Journals (Sweden)

    Wan Abd Al Qadr Imad Wan-Mohtar

    2016-09-01

    Full Text Available The morphology of Ganoderma lucidum BCCM 31549 mycelium in a repeated-batch fermentation (RBF was studied for exopolysaccharide (EPS production. RBF was optimised for time to replace and volume to replace. G. lucidum mycelium showed the ability to self-immobilise and exhibited high stability for repeated use in RBF with engulfed pellets. Furthermore, the ovoid and starburst-like pellet morphology was disposed to EPS production in the shake flask and bioreactor, respectively. Seven RBF could be carried out in 500 mL flasks, and five repeated batches were performed in a 2 L bioreactor. Under RBF conditions, autolysis of pellet core in the shake flask and shaving off of the outer hairy region in the bioreactor were observed at the later stages of RBF (R4 for the shake flask and R6 for the bioreactor. The proposed strategy showed that the morphology of G. lucidum mycelium can withstand extended fermentation cycles.

  13. Sample size for morphological traits of pigeonpea

    Directory of Open Access Journals (Sweden)

    Giovani Facco

    2015-12-01

    Full Text Available The objectives of this study were to determine the sample size (i.e., number of plants required to accurately estimate the average of morphological traits of pigeonpea (Cajanus cajan L. and to check for variability in sample size between evaluation periods and seasons. Two uniformity trials (i.e., experiments without treatment were conducted for two growing seasons. In the first season (2011/2012, the seeds were sown by broadcast seeding, and in the second season (2012/2013, the seeds were sown in rows spaced 0.50 m apart. The ground area in each experiment was 1,848 m2, and 360 plants were marked in the central area, in a 2 m × 2 m grid. Three morphological traits (e.g., number of nodes, plant height and stem diameter were evaluated 13 times during the first season and 22 times in the second season. Measurements for all three morphological traits were normally distributed and confirmed through the Kolmogorov-Smirnov test. Randomness was confirmed using the Run Test, and the descriptive statistics were calculated. For each trait, the sample size (n was calculated for the semiamplitudes of the confidence interval (i.e., estimation error equal to 2, 4, 6, ..., 20% of the estimated mean with a confidence coefficient (1-? of 95%. Subsequently, n was fixed at 360 plants, and the estimation error of the estimated percentage of the average for each trait was calculated. Variability of the sample size for the pigeonpea culture was observed between the morphological traits evaluated, among the evaluation periods and between seasons. Therefore, to assess with an accuracy of 6% of the estimated average, at least 136 plants must be evaluated throughout the pigeonpea crop cycle to determine the sample size for the traits (e.g., number of nodes, plant height and stem diameter in the different evaluation periods and between seasons. 

  14. Morphological evolution of Bi2Se3 nanocrystalline materials synthesized by microwave assisted solvothermal method

    Science.gov (United States)

    Bera, Sumit; Behera, P.; Mishra, A. K.; Krishnan, M.; Patidar, M. M.; Singh, D.; Gangrade, M.; Venkatesh, R.; Deshpande, U. P.; Phase, D. M.; Ganesan, V.

    2018-04-01

    Structural, morphological and spectroscopic properties of Bi2Se3 nanoparticles synthesized by microwave assisted solvothermal method were investigated systematically. A controlled synthesis of different morphologies by a small variation in synthesis procedure is demonstrated. Powder X-ray diffraction (XRD) confirmed the formation of single phase. Crystallite and particle size reductions were studied with XRD and AFM (Atomic Force Microscopy). Different morphologies such as hexagonal nanoflakes with cross section of around˜6µm, nanoflower and octahedral agglomerated crystals of nearly ˜60 nm size have been observed in scanning electron microscope while varying the microwave assisted synthesis procedures. A significant blue shift observed in diffuse reflectance spectroscopy evidences the energy gap tuning as a result of morphological evolution. The difference in morphology observed in this three fast, facile and scalable synthesis is advantageous for tuning the thermoelectric figure of merit and for probing the surface states of these topological insulators. Low temperature resistivity remains similar for all three variants depicting a 2D character as evidenced by a -lnT term of localization.

  15. L2 Selves, Emotions, and Motivated Behaviors

    Science.gov (United States)

    Teimouri, Yasser

    2017-01-01

    This study has aimed to investigate language learners' emotional experiences through the lens of L2 future self-guides. To that end, the L2 motivational self system was chosen as the theoretical framework to relate learners' emotions to their L2 selves. However, due to inconsistent results of past research concerning the motivational role of the…

  16. The effect of the triblock properties on the morphologies and photophysical properties of nanoparticle loaded with carboxylic dendrimer phthalocyanine

    Science.gov (United States)

    Lv, Huafei; Chen, Zhe; Yu, Xinxin; Pan, Sujuan; Zhang, Tiantian; Xie, Shusen; Yang, Hongqin; Peng, Yiru

    2016-09-01

    Photodynamic therapy (PDT) is an emerging alternative treatment for various cancers and age-related macular degeneration. Phthalocyanines (Pcs) and their substituted derivatives are under intensive investigation as the second generation photosensitizers. A big challenge for the application of Pcs is poor solubility and limited accumulation in the tumor tissues, which severely reduced its PDT efficacy. Nano-delivery systems such as polymeric micelles are promising tools for increasing the solubility and improving delivery efficiency of Pcs for PDT application. In this paper, nanoparticles of amphiphilic triblock copolymer poly(L-lysine)-b-poly (ethylene glycol)-b-poly(L-lysine) were developed to encapsulate 1-2 generation carboxylic poly (benzyl aryl ether) dendrimer. The morphologies and photophysical properties of polymeric nanoparticles loaded with 1-2 generation dendritic phthalocyanines (G1-ZnPc(COOH)8/m and G2-ZnPc(COOH)16/m) were studied by AFM, UV/Vis and fluorescent spectroscopic method. The morphologies of self-assembled PLL-PEG-PLL aggregates exhibited concentration dependence. Its morphologies changed from cocoon-like to spheral. The diameters of G1-ZnPc(COOH)8/m and G2-ZnPc(COOH)16/m were in the range of 33-147 nm, increasing with the increase of the concentration of PLL-PEG-PLL. The morphologies of G2-ZnPc(COOH)16/m also changed from cocoon-like to sphere with the increase of the concentration of PLL-PEG-PLL. It was found that, the no obviously Q change was observed between the free phthalocyanines and nanoparticles. The fluorescence intensity of polymer nanoparticles were higher enhanced compared with free dendritic phthalocyanines. The dendrimer phthalocyanine loaded with poly(L-lysine)-b-poly (ethylene glycol)-b-poly(L-lysine) presented suitable physical stability, improved photophysical properties suggesting it may be considered as a promising formulation for PDT.

  17. Le web social – La complexité au service de l'apprentissage informel de l'anglais The social web: complexity in the service of the informal learning of English

    Directory of Open Access Journals (Sweden)

    Geoffrey Sockett

    2012-06-01

    Full Text Available Cet article présente les résultats d'un projet de recherche dans lequel de futurs enseignants de langues sont invités à écrire un blogue au sujet de leurs activités informelles de réseautage social en anglais. Les participants, qui ont suivi une formation dans des domaines tels que les théories de l'acquisition des langues, s'expriment en particulier sur l'impact de ces activités sur leur apprentissage de la langue cible. Le corpus ainsi obtenu est analysé et des résultats sont présentés. Le cadre théorique de cette étude est celui des systèmes complexes et dynamiques. Nous soulignons la pertinence de ce modèle pour décrire l'apprentissage informel de l'anglais en ligne. Les résultats de l'étude font apparaître que le très grand nombre d'interactions entre personnes, médias, langues et interfaces de réseautage social conduit à un développement langagier non linéaire et à des transitions entre différentes phases dans des domaines tels que l'aisance et l'acquisition du vocabulaire. Nous présentons des applications pratiques de cette recherche pour l'enseignement des langues, notamment dans la valorisation des pratiques informelles, et suggérons de futures orientations pour la recherche dans ce domaine.This article presents the results of a research project using blogs written by trainee language teachers to report on their informal online social networking activities in English. The respondents, who are trained in areas such as language acquisition theories, are invited to discuss how they might be learning English through these activities. The resulting corpus of blogs is analysed and the impact of these activities on learning of the target language is discussed. The theoretical framework for this study is dynamic systems theory, and it is argued that this model is particularly pertinent for the description of language learning in an informal online context. The results of the study suggest that the very large

  18. Native language change during early stages of second language learning.

    Science.gov (United States)

    Bice, Kinsey; Kroll, Judith F

    2015-11-11

    Research on proficient bilinguals has demonstrated that both languages are always active, even when only one is required. The coactivation of the two languages creates both competition and convergence, facilitating the processing of cognate words, but slowing lexical access when there is a requirement to engage control mechanisms to select the target language. Critically, these consequences are evident in the native language (L1) as well as in the second language (L2). The present study questioned whether L1 changes can be detected at early stages of L2 learning and how they are modulated by L2 proficiency. Native English speakers learning Spanish performed an English (L1) lexical decision task that included cognates while event-related potentials were recorded. They also performed verbal fluency, working memory, and inhibitory control tasks. A group of matched monolinguals performed the same tasks in English only. The results revealed that intermediate learners demonstrate a reduced N400 for cognates compared with noncognates in English (L1), and an emerging effect is visually present in beginning learners as well; however, no behavioral cognate effect was present for either group. In addition, slower reaction times in English (L1) are related to a larger cognate N400 magnitude in English (L1) and Spanish (L2), and to better inhibitory control for learners but not for monolinguals. The results suggest that contrary to the claim that L2 affects L1 only when L2 speakers are highly proficient, L2 learning begins to impact L1 early in the development of the L2 skill.

  19. Caloric restriction increases learning consolidation and facilitates synaptic plasticity through mechanisms dependent on NR2B subunits of the NMDA receptor.

    Science.gov (United States)

    Fontán-Lozano, Angela; Sáez-Cassanelli, José Luis; Inda, Mari Carmen; de los Santos-Arteaga, Mercedes; Sierra-Domínguez, Sergio Antonio; López-Lluch, Guillermo; Delgado-García, José María; Carrión, Angel Manuel

    2007-09-19

    One of the main focal points of aging research is the search for treatments that will prevent or ameliorate the learning and memory deficiencies associated with aging. Here we have examined the effects of maintaining mature mice on a long-term intermittent fasting diet (L-IFD). We found that L-IFD enhances learning and consolidation processes. We also assessed the long-term changes in synaptic efficiency in these animals. L-IFD mice showed an increase in low-theta-band oscillations, paired-pulse facilitation, and facilitation of long-term synaptic plasticity in the hippocampus with respect to mice fed ad libitum. In addition, we found an increase in the expression of the NMDA receptor subunit NR2B in some brain areas of L-IFD mice. Specific antagonism of this subunit in the hippocampus reversed the beneficial effects of L-IFD. These data provide a molecular and cellular mechanism by which L-IFD may enhance cognition, ameliorating some aging-associated cognitive deficits.

  20. Cryogenic-SEM investigation of CO{sub 2} hydrate morphologies

    Energy Technology Data Exchange (ETDEWEB)

    Camps, A.P.; Milodowski, A.; Rochelle, C.; Williams, J.F.; Jackson, P. D. [British Geological Survey, Keyworth, Nottinghamshire (United Kingdom); Camps, A.P; Lovell, M.; Williams, J.F. [Leicester Univ., Leicester (United Kingdom). Dept. of Geology

    2008-07-01

    Gas hydrates occur naturally around the world in the shallow-marine geosphere, and are seen as a drilling hazard in the petroleum industry due to their role in the carbon cycle, and their possible contribution in past and present climate change. Hydrates are ice-like structures composed of cages of water molecules containing one or more guest molecules, such as methane and carbon dioxide (CO{sub 2}). CO{sub 2} hydrates also occur naturally on earth and are being investigated for their potential to store large volumes of CO{sub 2} to reduce atmospheric emissions of greenhouse gases as a climate change mitigation strategy. However, the mineralogy and formation processes of hydrates are relatively poorly understood. Different imaging techniques have been utilized to study gas hydrates, such as nuclear magnetic resonance, magnetic resonance imaging, and x-ray computed tomography. Scanning Electron Microscopy (SEM) at cryogenic temperatures is another technique to study hydrates, and has been used successfully for investigation of methane and CO{sub 2} hydrates. This paper presented a study that investigated CO{sub 2} hydrates formed in laboratories, using a cryogenic-SEM. The paper presented the study methods and observations, including euhedral crystalline carbon dioxide hydrate; acicular carbon dioxide hydrate; granoblastic carbon dioxide hydrate; and gas rich carbon dioxide hydrate. It was concluded that the investigation produced various different hydrate morphologies resulting from different formation conditions. Morphologies ranged from well-defined euhedral crystals to acicular needles, and more complex, intricate forms. 22 refs., 6 figs., 1 appendix.

  1. Characterization of dispersed and aggregated Al2O3 morphologies for predicting nanofluid thermal conductivities

    International Nuclear Information System (INIS)

    Feng Xuemei; Johnson, Drew W.

    2013-01-01

    Nanofluids are reported to have enhanced thermal conductivities resulting from nanoparticle aggregation. The goal of this study was to explore through experimental measurements, dispersed and aggregated morphology effects on enhanced thermal conductivities for Al 2 O 3 nanoparticles with a primary size of 54.2 ± 2.0 nm. Aggregation effects were investigated by measuring thermal conductivity of different particle morphologies that occurred under different aggregation conditions. Fractal dimensions and aspect ratios were used to quantify the aggregation morphologies. Fractal dimensions were measured using static light scattering and imaging techniques. Aspect ratios were measured using dynamic light scattering, scanning electron microscopy, and atomic force microscopy. Results showed that the enhancements in thermal conductivity can be predicted with effective medium theory when aspect ratio was considered.

  2. An Exploration of Language Anxiety in L2 Academic Context for Chinese International Students in U.S. Universities

    Science.gov (United States)

    Zhao, Qing

    2013-01-01

    This mix-methods study examined the language anxiety levels that the Chinese international students perceived in second language (L2) academic context at four universities in the northeastern region of the United States of America; it explored the impact of language anxiety that these students perceived on their academic learning; it also…

  3. How does language distance between L1 and L2 affect the L2 brain network? An fMRI study of Korean-Chinese-English trilinguals.

    Science.gov (United States)

    Kim, Say Young; Qi, Ting; Feng, Xiaoxia; Ding, Guosheng; Liu, Li; Cao, Fan

    2016-04-01

    The present study tested the hypothesis that language distance between first language (L1) and second language (L2) influences the assimilation and accommodation pattern in Korean-Chinese-English trilinguals. The distance between English and Korean is smaller than that between Chinese and Korean in terms of orthographic transparency, because both English and Korean are alphabetic, whereas Chinese is logographic. During fMRI, Korean trilingual participants performed a visual rhyming judgment task in three languages (Korean: KK, Chinese: KC, English: KE). Two L1 control groups were native Chinese and English speakers performing the task in their native languages (CC and EE, respectively). The general pattern of brain activation of KC was more similar to that of CC than KK, suggesting accommodation. Higher accuracy in KC was associated with decreased activation in regions of the KK network, suggesting reduced assimilation. In contrast, the brain activation of KE was more similar to that of KK than EE, suggesting assimilation. Higher accuracy in KE was associated with decreased activation in regions of the EE network, suggesting reduced accommodation. Finally, an ROI analysis on the left middle frontal gyrus revealed greater activation for KC than for KE, suggesting its selective involvement in the L2 with more arbitrary mapping between orthography and phonology (i.e., Chinese). Taken together, the brain network involved in L2 reading is similar to the L1 network when L2 and L1 are similar in orthographic transparency, while significant accommodation is expected when L2 is more opaque than L1. Copyright © 2015. Published by Elsevier Inc.

  4. Morphology of growth of Bi2Sr2CaCu2O8 single crystals

    Science.gov (United States)

    Indenbom, M. V.; van der Beek, C. J.; Berseth, V.; Wolf, Th.; Berger, H.; Benoit, W.

    1996-12-01

    A good correlation of twins on the basal surface of flux-grown Bi2Sr2CaCu2Ox (BSCCO) single crystals with surface. growth steps is observed, the b-axis being perpendicular to the steps and, thus, parallel to the growth direction. It is found that mono-twin BSCCO single crystals produced by the travelling solvent floating zone method also grow preferentially along b, i.e. nearly perpendicularly to the boule axis, contrary to the common belief. This new understanding of the morphology of growth explains the nature of major defects in these crystals, which considerably change their measured superconducting properties, in a different way.

  5. The Impact of Choice on EFL Students' Motivation and Engagement with L2 Vocabulary Learning

    Science.gov (United States)

    Wang, Han-Chung; Huang, Hung-Tzu; Hsu, Chun-Chieh

    2015-01-01

    The current study investigates EFL college learners' motivation and engagement during English vocabulary learning tasks. By adopting self-determination theory (SDT; Deci & Ryan, 1985, 2000), the study looked into the impact of autonomy on college students' task motivation and engagement with vocabulary learning tasks and their general English…

  6. L1-L2 Transfer in the Narrative Styles of Chinese EFL Learners' Written Personal Narratives

    Science.gov (United States)

    Su, I-Ru; Chou, Yi-Chun

    2016-01-01

    Most of the research on second language (L2) narratives has focused on whether or how L2 learners carry their L1 narrative styles into L2 narration; few studies have explored whether L2 learners' knowledge of the L2 also in turn affects their L1 narrative performance. The present study attempted to probe the issue of cultural transfer in narrative…

  7. High concentration of vitamin E decreases thermosensation and thermotaxis learning and the underlying mechanisms in the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Li, Yiping; Li, Yinxia; Wu, Qiuli; Ye, Huayue; Sun, Lingmei; Ye, Boping; Wang, Dayong

    2013-01-01

    α-tocopherol is a powerful liposoluble antioxidant and the most abundant isoform of vitamin E in the body. Under normal physiological conditions, adverse effects of relatively high concentration of vitamin E on organisms and the underlying mechanisms are still largely unclear. In the present study, we used the nematode Caenorhabditis elegans as an in vivo assay system to investigate the possible adverse effects of high concentration of vitamin E on thermosensation and thermotaxis learning and the underlying mechanisms. Our data show that treatment with 100-200 µg/mL of vitamin E did not noticeably influence both thermosensation and thermotaxis learning; however, treatment with 400 µg/mL of vitamin E altered both thermosensation and thermotaxis learning. The observed decrease in thermotaxis learning in 400 µg/mL of vitamin E treated nematodes might be partially due to the moderate but significant deficits in thermosensation, but not due to deficits in locomotion behavior or perception to food and starvation. Treatment with 400 µg/mL of vitamin E did not noticeably influence the morphology of GABAergic neurons, but significantly decreased fluorescent intensities of the cell bodies in AFD sensory neurons and AIY interneurons, required for thermosensation and thermotaxis learning control. Treatment with 400 µg/mL of vitamin E affected presynaptic function of neurons, but had no remarkable effects on postsynaptic function. Moreover, promotion of synaptic transmission by activating PKC-1 effectively retrieved deficits in both thermosensation and thermotaxis learning induced by 400 µg/mL of vitamin E. Therefore, relatively high concentrations of vitamin E administration may cause adverse effects on thermosensation and thermotaxis learning by inducing damage on the development of specific neurons and presynaptic function under normal physiological conditions in C. elegans.

  8. NaGd(MoO4)2 nanocrystals with diverse morphologies: controlled synthesis, growth mechanism, photoluminescence and thermometric properties.

    Science.gov (United States)

    Li, Anming; Xu, Dekang; Lin, Hao; Yang, Shenghong; Shao, Yuanzhi; Zhang, Yueli

    2016-08-10

    Pure tetragonal phase, uniform and well-crystallized sodium gadolinium molybdate (NaGd(MoO4)2) nanocrystals with diverse morphologies, e.g. nanocylinders, nanocubes and square nanoplates have been selectively synthesized via oleic acid-mediated hydrothermal method. The phase, structure, morphology and composition of the as-synthesized products are studied. Contents of both sodium molybdate and oleic acid of the precursor solutions are found to affect the morphologies of the products significantly, and oleic acid plays a key role in the morphology-controlled synthesis of NaGd(MoO4)2 nanocrystals with diverse morphologies. Growth mechanism of NaGd(MoO4)2 nanocrystals is proposed based on time-dependent morphology evolution and X-ray diffraction analysis. Morphology-dependent down-shifting photoluminescence properties of NaGd(MoO4)2: Eu(3+) nanocrystals, and upconversion photoluminescence properties of NaGd(MoO4)2: Yb(3+)/Er(3+) and Yb(3+)/Tm(3+) nanoplates are investigated in detail. Charge transfer band in the down-shifting excitation spectra shows a slight blue-shift, and the luminescence intensities and lifetimes of Eu(3+) are decreased gradually with the morphology of the nanocrystals varying from nanocubes to thin square nanoplates. Upconversion energy transfer mechanisms of NaGd(MoO4)2: Yb(3+)/Er(3+), Yb(3+)/Tm(3+) nanoplates are proposed based on the energy level scheme and power dependence of upconversion emissions. Thermometric properties of NaGd(MoO4)2: Yb(3+)/Er(3+) nanoplates are investigated, and the maximum sensitivity is determined to be 0.01333 K(-1) at 285 K.

  9. Immunogenicity of an HPV-16 L2 DNA vaccine

    Science.gov (United States)

    Hitzeroth, Inga I.; Passmore, Jo-Ann S.; Shephard, Enid; Stewart, Debbie; Müller, Martin; Williamson, Anna-Lise; Rybicki, Edward P.; Kast, W. Martin

    2009-01-01

    The ability to elicit cross-neutralizing antibodies makes human papillomavirus (HPV) L2 capsid protein a possible HPV vaccine. We examined and compared the humoral response of mice immunised with a HPV-16 L2 DNA vaccine or with HPV-16 L2 protein. The L2 DNA vaccine elicited a non-neutralising antibody response unlike the L2 protein. L2 DNA vaccination suppressed the growth of L2-expressing C3 tumor cells, which is a T cell mediated effect, demonstrating that the lack of non-neutralizing antibody induction by L2 DNA was not caused by lack of T cell immunogenicity of the construct. PMID:19559114

  10. Tactile learning and the individual evaluation of the reward in honey bees (Apis mellifera L.).

    Science.gov (United States)

    Scheiner, R; Erber, J; Page, R E

    1999-07-01

    Using the proboscis extension response we conditioned pollen and nectar foragers of the honey bee (Apis mellifera L.) to tactile patterns under laboratory conditions. Pollen foragers demonstrated better acquisition, extinction, and reversal learning than nectar foragers. We tested whether the known differences in response thresholds to sucrose between pollen and nectar foragers could explain the observed differences in learning and found that nectar foragers with low response thresholds performed better during acquisition and extinction than ones with higher thresholds. Conditioning pollen and nectar foragers with similar response thresholds did not yield differences in their learning performance. These results suggest that differences in the learning performance of pollen and nectar foragers are a consequence of differences in their perception of sucrose. Furthermore, we analysed the effect which the perception of sucrose reward has on associative learning. Nectar foragers with uniform low response thresholds were conditioned using varying concentrations of sucrose. We found significant positive correlations between the concentrations of the sucrose rewards and the performance during acquisition and extinction. The results are summarised in a model which describes the relationships between learning performance, response threshold to sucrose, concentration of sucrose and the number of rewards.

  11. Electrophysiological Correlates of Error Monitoring and Feedback Processing in Second Language Learning.

    Science.gov (United States)

    Bultena, Sybrine; Danielmeier, Claudia; Bekkering, Harold; Lemhöfer, Kristin

    2017-01-01

    Humans monitor their behavior to optimize performance, which presumably relies on stable representations of correct responses. During second language (L2) learning, however, stable representations have yet to be formed while knowledge of the first language (L1) can interfere with learning, which in some cases results in persistent errors. In order to examine how correct L2 representations are stabilized, this study examined performance monitoring in the learning process of second language learners for a feature that conflicts with their first language. Using EEG, we investigated if L2 learners in a feedback-guided word gender assignment task showed signs of error detection in the form of an error-related negativity (ERN) before and after receiving feedback, and how feedback is processed. The results indicated that initially, response-locked negativities for correct (CRN) and incorrect (ERN) responses were of similar size, showing a lack of internal error detection when L2 representations are unstable. As behavioral performance improved following feedback, the ERN became larger than the CRN, pointing to the first signs of successful error detection. Additionally, we observed a second negativity following the ERN/CRN components, the amplitude of which followed a similar pattern as the previous negativities. Feedback-locked data indicated robust FRN and P300 effects in response to negative feedback across different rounds, demonstrating that feedback remained important in order to update memory representations during learning. We thus show that initially, L2 representations may often not be stable enough to warrant successful error monitoring, but can be stabilized through repeated feedback, which means that the brain is able to overcome L1 interference, and can learn to detect errors internally after a short training session. The results contribute a different perspective to the discussion on changes in ERN and FRN components in relation to learning, by extending the

  12. Morphology, deformation, and defect structures of TiCr2 in Ti-Cr alloys

    International Nuclear Information System (INIS)

    Chen, K.C.; Allen, S.M.; Livingston, J.D.

    1992-01-01

    The morphologies and defect structures of TiCr 2 in several Ti-Cr alloys have been examined by optical metallography, x-ray diffraction, and transmission electron microscopy (TEM), in order to explore the room-temperature deformability of the Laves phase TiCr 2 . The morphology of the Laves phase was found to be dependent upon alloy composition and annealing temperature. Samples deformed by compression have also been studied using TEM. Comparisons of microstructures before and after deformation suggest an increase in twin, stacking fault, and dislocation density within the Laves phase, indicating some but not extensive room-temperature deformability

  13. The Effects of Word Exposure Frequency and Elaboration of Word Processing on Incidental L2 Vocabulary Acquisition through Reading

    Science.gov (United States)

    Eckerth, Johannes; Tavakoli, Parveneh

    2012-01-01

    Research on incidental second language (L2) vocabulary acquisition through reading has claimed that repeated encounters with unfamiliar words and the relative elaboration of processing these words facilitate word learning. However, so far both variables have been investigated in isolation. To help close this research gap, the current study…

  14. Morphological and physiological features of the species Asimina triloba (L. dunal, introduced as an ornamental plant in Baia Mare (Maramureş county, Romania

    Directory of Open Access Journals (Sweden)

    Beatrice SZILAGYI

    2011-11-01

    of the 1-2 years; 3. – the dynamic of photosynthesis intensity in these plants, during the day, during summer/autumn months.The study results are promising for acclimatization of the species Asimina triloba (L. Dunal in particular conditions of Baia Mare. Morphological and physiological parametres tested are maintaned at similar to those of native habitat, described in the literature.

  15. ReMashed – Recommendation Approaches for Mash-Up Personal Learning Environments in Formal and Informal Learning Settings

    NARCIS (Netherlands)

    Drachsler, Hendrik; Pecceu, Dries; Arts, Tanja; Hutten, Edwin; Rutledge, Lloyd; Van Rosmalen, Peter; Hummel, Hans; Koper, Rob

    2009-01-01

    Drachsler, H., Peccau, D., Arts, T., Hutten, E., Rutledge, L., Van Rosmalen, P., Hummel, H. G. K., & Koper, R. (2009). ReMashed – Recommendation Approaches for Mash-Up Personal Learning Environments in Formal and Informal Learning Settings. Presentation at the 2nd Workshop Mash-Up Personal Learning

  16. Talking It Through: Collaborative Dialogue and Second Language Learning

    Science.gov (United States)

    Ammar, Ahlem; Hassan, Rania Mohamed

    2018-01-01

    This quasi-experimental study examined the potential benefits of zero-error dictation, a teaching technique based on dialogue-driven dictation, and the extent to which target linguistic features and proficiency levels mediated its effects on second language (L2) learners' accurate use of French grammatical morphology. Seventy-nine learners of L2

  17. Summary and evaluation: fuel dynamics loss-of-flow experiments (tests L2, L3, and L4)

    International Nuclear Information System (INIS)

    Barts, E.W.; Deitrich, L.W.; Eberhart, J.G.; Fischer, A.K.; Meek, C.C.

    1975-09-01

    Three similar experiments conducted to support the analyses of hypothetical LMFBR unprotected-loss-of-flow accidents are summarized and evaluated. The tests, designated L2, L3, and L4, provided experimental data against which accident-analysis codes could be compared, so as to guide further analysis and modeling of the initiating phases of the hypothetical accident. The tests were conducted using seven-pin bundles of mixed-oxide fuel pins in Mark-II flowing-sodium loops in the TREAT reactor. Test L2 used fresh fuel. Tests L3 and L4 used irradiated fuel pins having, respectively, ''intermediate-power'' (no central void) and ''high-power'' (fully developed central void) microstructure. 12 references

  18. Changes in White-Matter Connectivity in Late Second Language Learners: Evidence from Diffusion Tensor Imaging

    Directory of Open Access Journals (Sweden)

    Eleonora Rossi

    2017-11-01

    Full Text Available Morphological brain changes as a consequence of new learning have been widely established. Learning a second language (L2 is one such experience that can lead to rapid structural neural changes. However, still relatively little is known about how levels of proficiency in the L2 and the age at which the L2 is learned influence brain neuroplasticity. The goal of this study is to provide novel evidence for the effect of bilingualism on white matter structure in relatively proficient but late L2 learners who acquired the second language after early childhood. Overall, the results demonstrate a significant effect on white matter fractional anisotropy (FA as a function of L2 learning. Higher FA values were found in a broad white matter network including the anterior thalamic radiation (ATR, the inferior fronto-occipital fasciculus (IFOF, the Uncinate Fasciculus (UF, and the inferior longitudinal fasciculus (ILF. Moreover, FA values were correlated with age of L2 acquisition, suggesting that learning an L2, even past childhood, induces neural changes. Finally, these results provide some initial evidence that variability in the age of L2 acquisition has important consequences for neural plasticity.

  19. Complexation-tailored morphology of asymmetric block copolymer membranes

    KAUST Repository

    Madhavan, Poornima

    2013-08-14

    Hydrogen-bond formation between polystyrene-b-poly (4-vinylpyridine) (PS-b-P4VP) block copolymer (BCP) and -OH/-COOH functionalized organic molecules was used to tune morphology of asymmetric nanoporous membranes prepared by simultaneous self-assembly and nonsolvent induced phase separation. The morphologies were characterized by field emmision scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Hydrogen bonds were confirmed by infrared (IR), and the results were correlated to rheology characterization. The OH-functionalized organic molecules direct the morphology into hexagonal order. COOH-functionalized molecules led to both lamellar and hexagonal structures. Micelle formation in solutions and their sizes were determined using dynamic light scattering (DLS) measurements and water fluxes of 600-3200 L/m 2·h·bar were obtained. The pore size of the plain BCP membrane was smaller than with additives. The following series of additives led to pores with hexagonal order with increasing pore size: terephthalic acid (COOH-bifunctionalized) < rutin (OH-multifunctionalized) < 9-anthracenemethanol (OH-monofunctionalized) < 3,5-dihydroxybenzyl alcohol (OH-trifunctionalized). © 2013 American Chemical Society.

  20. Complexation-tailored morphology of asymmetric block copolymer membranes

    KAUST Repository

    Madhavan, Poornima; Peinemann, Klaus-Viktor; Nunes, Suzana Pereira

    2013-01-01

    Hydrogen-bond formation between polystyrene-b-poly (4-vinylpyridine) (PS-b-P4VP) block copolymer (BCP) and -OH/-COOH functionalized organic molecules was used to tune morphology of asymmetric nanoporous membranes prepared by simultaneous self-assembly and nonsolvent induced phase separation. The morphologies were characterized by field emmision scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Hydrogen bonds were confirmed by infrared (IR), and the results were correlated to rheology characterization. The OH-functionalized organic molecules direct the morphology into hexagonal order. COOH-functionalized molecules led to both lamellar and hexagonal structures. Micelle formation in solutions and their sizes were determined using dynamic light scattering (DLS) measurements and water fluxes of 600-3200 L/m 2·h·bar were obtained. The pore size of the plain BCP membrane was smaller than with additives. The following series of additives led to pores with hexagonal order with increasing pore size: terephthalic acid (COOH-bifunctionalized) < rutin (OH-multifunctionalized) < 9-anthracenemethanol (OH-monofunctionalized) < 3,5-dihydroxybenzyl alcohol (OH-trifunctionalized). © 2013 American Chemical Society.

  1. Morphological and anatomical features of achenes of Anemone L. (Ranunculaceae Juss. of the flora of Ukraine

    Directory of Open Access Journals (Sweden)

    О.М. Tsarenko

    2016-06-01

    Full Text Available Based on SEM and LM some morphological and anatomical features of achenes of Anemone L. of Ukrainian flora (A. narcissiflora, A. sylvestris, A. nemorosa, A. narcissiflora have been investigated. Сarpological features after which it is possible to diagnose species are detected: the dimensions and shape of the achenes and beaks, the peculiarities of pubescence (length and character of localization of the hairs, a presence of different appendages of pericarp (as ribs or wings which surround body of fruit, thickness of pericarp and peculiarities of the thickness of the cell walls of endocarp. Detailed descriptions of fruitlets have been represented. The key for determination of species not in a flourishing condition on the revealed signs have been composed. Data obtained are important for systematics and phylogeny of the genus and the family as a whole.

  2. Operationalizing Multilingualism: Language Learning Motivation in Turkey

    Science.gov (United States)

    Thompson, Amy S.; Erdil-Moody, Zeynep

    2016-01-01

    This study is an examination of language learning motivation and multilingual status in the Turkish English as a foreign language (EFL) context. Using Dörnyei's L2 Motivational Self System (L2MSS) framework, specifically the ideal and ought-to L2 selves, this study examines the relationship between motivation and two operationalizations of…

  3. GALAXY ZOO MORPHOLOGY AND PHOTOMETRIC REDSHIFTS IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Way, M. J.

    2011-01-01

    It has recently been demonstrated that one can accurately derive galaxy morphology from particular primary and secondary isophotal shape estimates in the Sloan Digital Sky Survey (SDSS) imaging catalog. This was accomplished by applying Machine Learning techniques to the Galaxy Zoo morphology catalog. Using the broad bandpass photometry of the SDSS in combination with precise knowledge of galaxy morphology should help in estimating more accurate photometric redshifts for galaxies. Using the Galaxy Zoo separation for spirals and ellipticals in combination with SDSS photometry we attempt to calculate photometric redshifts. In the best case we find that the root-mean-square error for luminous red galaxies classified as ellipticals is as low as 0.0118. Given these promising results we believe better photometric redshift estimates for all galaxies in the SDSS (∼350 million) will be feasible if researchers can also leverage their derived morphologies via Machine Learning. These initial results look to be promising for those interested in estimating weak lensing, baryonic acoustic oscillation, and other fields dependent upon accurate photometric redshifts.

  4. Morphological Change and Decreasing Transfer Rate of Biofilm-Featured Listeria monocytogenes EGDe.

    Science.gov (United States)

    Lee, Yuejia; Wang, Chinling

    2017-03-01

    Listeria monocytogenes , a lethal foodborne pathogen, has the ability to resist the hostile food processing environment and thus frequently contaminates ready-to-eat foods during processing. It is commonly accepted that the tendency of L. monocytogenes ' to generate biofilms on various surfaces enhances its resistance to the harshness of the food processing environment. However, the role of biofilm formation in the transferability of L. monocytogenes EGDe remains controversial. We examined the growth of Listeria biofilms on stainless steel surfaces and their effect on the transferability of L. monocytogenes EGDe. The experiments were a factorial 2 × 2 design with at least three biological replicates. Through scanning electron microscopy, a mature biofilm with intensive aggregates of cells was observed on the surface of stainless steel after 3 or 5 days of incubation, depending on the initial level of inoculation. During biofilm development, L. monocytogenes EGDe carried out binary fission vigorously before a mature biofilm was formed and subsequently changed its cellular morphology from rod shaped to sphere shaped. Furthermore, static biofilm, which was formed after 3 days of incubation at 25°C, significantly inhibited the transfer rate of L. monocytogenes EGDe from stainless steel blades to 15 bologna slices. During 7 days of storage at 4°C, however, bacterial growth rate was not significantly impacted by whether bacteria were transferred from biofilm and the initial concentrations of transferred bacteria on the slice. In conclusion, this study is the first to report a distinct change in morphology of L. monocytogenes EGDe at the late stage of biofilm formation. More importantly, once food is contaminated by L. monocytogenes EGDe, contamination proceeds independently of biofilm development and the initial level of contamination when food is stored at 4°C, even if contamination with L. monocytogenes EGDe was initially undetectable before storage.

  5. Towards adaptation in e-learning 2.0

    Science.gov (United States)

    Cristea, Alexandra I.; Ghali, Fawaz

    2011-04-01

    This paper presents several essential steps from an overall study on shaping new ways of learning and teaching, by using the synergetic merger of three different fields: Web 2.0, e-learning and adaptation (in particular, personalisation to the learner). These novel teaching and learning ways-the latter focus of this paper-are reflected in and finally adding to various versions of the My Online Teacher 2.0 adaptive system. In particular, this paper focuses on a study of how to more effectively use and combine the recommendation of peers and content adaptation to enhance the learning outcome in e-learning systems based on Web 2.0. In order to better isolate and examine the effects of peer recommendation and adaptive content presentation, we designed experiments inspecting collaboration between individuals based on recommendation of peers who have greater knowledge, and compare this to adaptive content recommendation, as well as to "simple" learning in a system with a minimum of Web 2.0 support. Overall, the results of adding peer recommendation and adaptive content presentation were encouraging, and are further discussed in detail in this paper.

  6. Ultrasensitive Electrochemical Detection of Clostridium perfringens DNA Based Morphology-Dependent DNA Adsorption Properties of CeO2 Nanorods in Dairy Products

    Directory of Open Access Journals (Sweden)

    Xingcan Qian

    2018-06-01

    Full Text Available Foodborne pathogens such as Clostridium perfringens can cause diverse illnesses and seriously threaten to human health, yet far less attention has been given to detecting these pathogenic bacteria. Herein, two morphologies of nanoceria were synthesized via adjusting the concentration of NaOH, and CeO2 nanorod has been utilized as sensing material to achieve sensitive and selective detection of C. perfringens DNA sequence due to its strong adsorption ability towards DNA compared to nanoparticle. The DNA probe was tightly immobilized on CeO2/chitosan modified electrode surface via metal coordination, and the DNA surface density was 2.51 × 10−10 mol/cm2. Under optimal experimental conditions, the electrochemical impedance biosensor displays favorable selectivity toward target DNA in comparison with base-mismatched and non-complementary DNA. The dynamic linear range of the proposed biosensor for detecting oligonucleotide sequence of Clostridium perfringens was from 1.0 × 10−14 to 1.0 × 10−7 mol/L. The detection limit was 7.06 × 10−15 mol/L. In comparison, differential pulse voltammetry (DPV method quantified the target DNA with a detection limit of 1.95 × 10−15 mol/L. Moreover, the DNA biosensor could detect C. perfringens extracted DNA in dairy products and provided a potential application in food quality control.

  7. Morfologi dan Pertumbuhan Planlet Hasil Induksi Poliploidi melalui Perlakuan Kolkisin pada Kuncup Bunga Anggrek Bulan (Phalaenopsis amabilis (L. Blume

    Directory of Open Access Journals (Sweden)

    Tubagus Kiki Kawakibi Azmi

    2016-06-01

    Full Text Available Induction of polyploid gametes is one of useful plant polyploidization methods. Some of its benefits are to obtain triploid and tetraploid progenies at the same time by cross and self pollination. Previous research showed that some morphological characters which could be the indications of polyploidy plantlets before the analysis of chromosome number. Colchicine treatment on flower bud of diploid Phalaenopsis amabilis was conducted to determine the effect of colchicine on flower bud development, plantlets morphology and growth, and potential of polyploidy induction based on plantlets morphology. Colchicine concentrations in the experiment were 0, 50, 500, 1,000, and 2,000 mg L-1, with three days duration of treatments with aluminium foil wraps on flower buds. The results showed that high colchicine concentrations (2,000 mg L-1 inhibited flowers blooming of treated flower buds. Based on morphological characters, plantlets were classified into normal and putative polyploid plantlets. Putative polyploid plantlets from colchicine with the concentration of 50, 500, and 1,000 mg L-1 were 71.2, 86.4, and 100.0% respectively.Keywords: colchicine concentration, morphological characters, normal plantlets, putative polyploidy, reproductive organ

  8. CANDELS: THE CORRELATION BETWEEN GALAXY MORPHOLOGY AND STAR FORMATION ACTIVITY AT z ∼ 2

    International Nuclear Information System (INIS)

    Lee, Bomee; Giavalisco, Mauro; Williams, Christina C.; Guo Yicheng; Faber, S. M.; Lotz, Jennifer; Ferguson, Henry C.; Koekemoer, Anton; Grogin, Norman; Van der Wel, Arjen; Kocevski, Dale; Conselice, Christopher J.; Wuyts, Stijn; Dekel, Avishai; Kartaltepe, Jeyhan; Bell, Eric F.

    2013-01-01

    We discuss the state of the assembly of the Hubble sequence in the mix of bright galaxies at redshift 1.4 AB ∼ 26, selected from the HST/ACS and WFC3 images of the GOODS-South field obtained as part of the GOODS and CANDELS observations. We investigate the relationship between the star formation properties and morphology using various parametric diagnostics, such as the Sérsic light profile, Gini (G), M 20 , concentration (C), asymmetry (A), and multiplicity (Ψ) parameters. Our sample clearly separates into massive, red, and passive galaxies versus less massive, blue, and star-forming ones, and this dichotomy correlates very well with the galaxies' morphological properties. Star-forming galaxies show a broad variety of morphological features, including clumpy structures and bulges mixed with faint low surface brightness features, generally characterized by disky-type light profiles. Passively evolving galaxies, on the other hand, very often have compact light distribution and morphology typical of today's spheroidal systems. We also find that artificially redshifted local galaxies have a similar distribution with z ∼ 2 galaxies in a G-M 20 plane. Visual inspection between the rest-frame optical and UV images show that there is a generally weak morphological k-correction for galaxies at z ∼ 2, but the comparison with non-parametric measures show that galaxies in the rest-frame UV are somewhat clumpier than rest-frame optical. Similar general trends are observed in the local universe among massive galaxies, suggesting that the backbone of the Hubble sequence was already in place at z ∼ 2

  9. The Influence of Schema and Cultural Difference on L1 and L2 Reading

    Science.gov (United States)

    Yang, Shi-sheng

    2010-01-01

    Reading in L1 shares numerous basic elements with reading in L2, and the processes also differ greatly. Intriguing questions involve whether there are two parallel cognitive processes at work, or whether there are processing strategies that accommodate both L1 and L2. This paper examines how reading in L1 is different from and similar to reading…

  10. IL WORKSHOP DI FONETICA IN ITALIANO L2/LS: ACCENTO DI PAROLA E DURATA SILLABICA

    Directory of Open Access Journals (Sweden)

    Lidia Calabrò

    2016-09-01

    Full Text Available Lavorare sugli aspetti fonetico-fonologici di una lingua straniera risulta quanto mai importante e fondamentale, soprattutto se la L1 degli apprendenti la L2/LS è molto distante. Attraverso un’esperienza iniziata con studenti sinofoni del progetto Marco Polo / Turandot, le attività inserite nel workshop di fonetica nell’italiano L2 si presentano come proposta di didattica integrativa al fine di sensibilizzare gli studenti ai tratti soprasegmentali della L2 a contrasto con quelli della loro L1. Nel presente contributo verranno presentate alcune attività riguardanti la percezione e la realizzazione della durata vocalica e della sillaba accentata attraverso attività collaborative e il movimento del corpo. Tutte le attività prevedono un coinvolgimento personale e totale del singolo apprendente e di tutta la classe in quanto il workshop si avvale di multimodalità, multimedialità e apprendimento collaborativo al fine di scoprire i suoni della L2 e riflettere sulla loro percezione e produzione. Italian L2/LS phonetic workshops: word accent and syllable duration Working on phonetics and the phonolgical aspects language is considered important and fundamental, above all if a learner’s L1 is distant from the SL. The activities described in the paper took place during a phonetic workshop in Italian as a second language with Chinese students enrolled in the Marco Polo/Turandot project. They can be considered a teaching technique aimed at raising student awareness about the SL supra-segmental aspects in contrast to their L1. Some activities related to vowel length and stress will be presented: perception and production, cooperative learning and body movement aimed at discovering and practicing vowel length in stressed syllables (phonic stress. The activities involved the students in a more personal, total and physical collaboration together with their classmates. The multimedia workshop was designed to be multimodal and cooperative, in order to

  11. In Vitro Propagation of Heliconia bihai (L. L. from Zygotic Embryos Propagação In vitro de Heliconia bihai (L. L. provenientes de embriões zigóticos

    Directory of Open Access Journals (Sweden)

    Cláudia Ulisses

    2010-03-01

    Full Text Available The internal morphology of embryos from immature and mature fruits of Heliconia bihai (L. L. cv. Lobster Claw Two was examined. Embryos were inoculated into MS media (full MS and ½ MS and GA3 (0, 2.5 and 5 mg L-1 with either sucrose or glucose. These plantlets were then replicated and transferred to MS medium (full MS or ½ MS with 0 or 2.5 mg L-1 BAP and their multiplication was evaluated 30 and 45 days after inoculation. The genetic variability of the multiplied plants was estimated using isoenzyme analyses. The internal morphology of the mature embryos revealed their tissues to be in more advanced stages of differentiation than immature embryos. In the conversion phase, 85% of the inoculated embryos developed into plants in the ½ MS medium with sucrose, in contrast to only 41% of the embryos that were cultivated with glucose. In the multiplication phase, plants cultivated in ½ MS medium with 2.5 mg L-1 BAP demonstrated more buds. Isoenzyme analyses showed pattern changes in terms of the color intensity and the migration of some of the bands. These results may be associated with differences in the ages of the mother plants and of the plantlets obtained in vitro.Inicialmente os embriões procedentes de frutos imaturos e maduros de Heliconia bihai (L. L. cv. Lobster Claw Two foram avaliados quanto à morfologia interna. Os embriões maduros foram inoculados em meio MS (1/2MS e MS completo e GA3 (0, 2,5 e 5,0 mg L-1, utilizando sacarose ou glucose. Posteriormente, as plantas obtidas foram transferidas para meio 1/2MS acrescido de 0 ou 2.5 mg L-1 de BAP e aos 30 e 45 dias após a inoculação, avaliou-se a formação de gemas laterais. Aos 45 dias avaliou-se a variabilidade genética dessas plantas através da análise isoenzimática. Ao avaliar a morfologia interna observou-se que os embriões maduros apresentaram estádios de diferenciação superior aos embriões imaturos. Na fase de conversão do embrião em planta, observou-se que 85% dos

  12. Growth, yield and fiber morphology of kenaf ( Hibiscus cannabinus L ...

    African Journals Online (AJOL)

    The effects of carbon levels on plant growth, yield and fiber morphological properties are not available for kenaf that is considered as a potential source of low cost natural fiber and feedstock for energy production as well. A pot-culture experiment was conducted in shade house to determine the effects of carbon levels on ...

  13. Quantitative assessment of morphology, T{sub 1ρ}, and T{sub 2} of shoulder cartilage using MRI

    Energy Technology Data Exchange (ETDEWEB)

    Nardo, Lorenzo; Carballido-Gamio, Julio; Tang, Solomon; Lai, Andrew; Krug, Roland [University of California, San Francisco, Musculoskeletal Quantitative Imaging Research Group, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

    2016-12-15

    The aim of this study was to assess the feasibility of quantifying shoulder cartilage morphology and relaxometry in a clinically feasible scan time comparing different pulse sequences and assessing their reproducibility at 3 Tesla. Three pulse sequences were compared for morphological assessments of shoulder cartilage thickness and volume (SPGR, MERGE, FIESTA), while a combined T1ρ-T2 sequence was optimized for relaxometry measurements. The shoulders of six healthy subjects were scanned twice with repositioning, and the cartilage was segmented and quantified. The degree of agreement between the three morphological sequences was assessed using Bland-Altman plots, while the morphological and relaxometry reproducibility were assessed with root-mean-square coefficients of variation (RMS-CVs) Bland-Altman plots indicated good levels of agreement between the morphological assessments of the three sequences. The reproducibility of morphological assessments yielded RMS-CVs between 4.0 and 17.7 %. All sequences correlated highly (R > 0.9) for morphologic assessments with no statistically significant differences. For relaxometry assessments of humeral cartilage, RMS-CVs of 6.4 and 10.6 % were found for T1ρ and T2, respectively. The assessment of both cartilage morphology and relaxometry is feasible in the shoulder with SPGR, humeral head, and T1ρ being the more reproducible morphological sequence, anatomic region, and quantitative sequence, respectively. (orig.)

  14. Searching for prostate cancer by fully automated magnetic resonance imaging classification: deep learning versus non-deep learning.

    Science.gov (United States)

    Wang, Xinggang; Yang, Wei; Weinreb, Jeffrey; Han, Juan; Li, Qiubai; Kong, Xiangchuang; Yan, Yongluan; Ke, Zan; Luo, Bo; Liu, Tao; Wang, Liang

    2017-11-13

    Prostate cancer (PCa) is a major cause of death since ancient time documented in Egyptian Ptolemaic mummy imaging. PCa detection is critical to personalized medicine and varies considerably under an MRI scan. 172 patients with 2,602 morphologic images (axial 2D T2-weighted imaging) of the prostate were obtained. A deep learning with deep convolutional neural network (DCNN) and a non-deep learning with SIFT image feature and bag-of-word (BoW), a representative method for image recognition and analysis, were used to distinguish pathologically confirmed PCa patients from prostate benign conditions (BCs) patients with prostatitis or prostate benign hyperplasia (BPH). In fully automated detection of PCa patients, deep learning had a statistically higher area under the receiver operating characteristics curve (AUC) than non-deep learning (P = 0.0007 deep learning method and 0.70 (95% CI 0.63-0.77) for non-deep learning method, respectively. Our results suggest that deep learning with DCNN is superior to non-deep learning with SIFT image feature and BoW model for fully automated PCa patients differentiation from prostate BCs patients. Our deep learning method is extensible to image modalities such as MR imaging, CT and PET of other organs.

  15. Action Control, L2 Motivational Self System, and Motivated Learning Behavior in a Foreign Language Learning Context

    Science.gov (United States)

    Khany, Reza; Amiri, Majid

    2018-01-01

    Theoretical developments in second or foreign language motivation research have led to a better understanding of the convoluted nature of motivation in the process of language acquisition. Among these theories, action control theory has recently shown a good deal of explanatory power in second language learning contexts and in the presence of…

  16. Temperature Effects on Stainless Steel 316L Corrosion in the Environment of Sulphuric Acid (H2SO4)

    Science.gov (United States)

    Ayu Arwati, I. G.; Herianto Majlan, Edy; Daud, Wan Ramli Wan; Shyuan, Loh Kee; Arifin, Khuzaimah Binti; Husaini, Teuku; Alfa, Sagir; Ashidiq, Fakhruddien

    2018-03-01

    In its application, metal is always in contact with its environment whether air, vapor, water, and other chemicals. During contact, chemical interactions emerge between metals and their respective environments such that the metal surface corrodes. This study aims to determine the corrosion rate of 316L stainless steel sulphuric acid environment (H2SO4) with weight loss and electrochemical methods. The corrosion rate (CR) is value of 316L stainless steel by weight loss method with sulfuric acid (H2SO4) with concentration of 0.5 M. The result obtained in conjunction with the increase of temperature the rate of erosion obtained appears to be larger, with a consecutive 3 hour the temperature of 50°C is 0.27 mg/cm2h, temperature 70°C 0.38 mg/cm2h, and temperature 90 °C 0.52 mg/cm2h. With the electrochemical method, the current value increases by using a C350 potentiostal tool. The higher the current, the longer the time the corrosion rate increases, where the current is at 90 °C with a 10-minute treatment time of 0.0014736 A. The 316L stainless steel in surface metal morphology is shown by using a Scanning Electron Microscope (SEM).

  17. Delayed vertebral diagnosed L4 pincer vertebral fracture, L2-L3 ruptured vertebral lumbar disc hernia, L5 vertebral wedge fracture - Case report

    OpenAIRE

    Balasa D; Schiopu M; Tunas A; Baz R; Hancu Anca

    2016-01-01

    An association between delayed ruptured lumbar disc hernia, L5 vertebral wedge fracture and posttraumaticL4 pincer vertebral fracture (A2.3-AO clasification) at different levels is a very rare entity. We present the case of a 55 years old male who falled down from a bicycle. 2 months later because of intense and permanent vertebral lumbar and radicular L2 and L3 pain (Visual Scal Autologus of Pain7-8/10) the patient came to the hospital. He was diagnosed with pincer vertebral L4 fracture (A2....

  18. Crystal and molecular structure of 2,2’-(quinoxaline-2,3-diyl)dipyridinium dinitrate (H_2L)(NO_3)_2

    International Nuclear Information System (INIS)

    Egorova, O. A.; Polyakova, I. N.; Sergienko, V. S.; Davydov, V. V.

    2016-01-01

    The crystal structure of 2,2’-(quinoxaline-2,3-diyl)dipyridinium dinitrate (H_2L)(NO_3)_2 is studied by X-ray diffraction (T = 150 K, R1 = 0.0467). The H_2L"2"+ cation is located on the twofold rotation axis and connected with two NO_3"− anions by strong N–H···O hydrogen bonds. Planar quinoxaline fragments of cations form stacks with the interplanar spacing of 3.308 Å. The structure of the diprotonated H_2L"2"+ cation is compared with those of the monoprotonated H_2L"2"+ cation and neutral L molecule.

  19. Morfologia da flor e formação do fruto no amendoim cultivado (Arachis hypogaea, L. Flower morphology and fruit development in the cultivated peanut (Arachis hypogaea L.

    Directory of Open Access Journals (Sweden)

    Candida H. T. M. Conagin

    1955-01-01

    Full Text Available O amendoim comum pertence à espécie Arachis hypogxa L. ; outras espécies não apresentam valor econômico algum. As variedades comerciais podem ser reunidas em três grupos - Virgínia, Spanish e Valência - de acôrdo com a distribuição das gemas vegetativas e reprodutivas e também com o número de sementes por fruto. Nêste trabalho é apresentado um estudo da morfologia, duração e fertilização da flor, mostrando que no amendoim não existe a suposta distinção de flôres férteis e estéreis. Também a formação do fruto é descrita, mostrando a interessante característica desta planta, que é ter flôres aéreas e frutos subterrâneos.This work is based mostly on the descriptions given in Smith's paper "Arachis hypogxa L. Aerial flower and Subterranean Fruit" (2 and in the symposium "The Peanut. The unpredictable Legume" (3, and also on some of the author's observations. All cultivated peanut varieties belong to the species Arachis hypogxa L.; other species of the genus are not used for commercial production and may be of interest only for breeding purposes. Commercial peanut varieties can be grouped into one of three types : Virginia, Spanish, and Valencia. This grouping is done according to the distribution of vegetative and reproductive buds on the plant, and to the number of seeds per fruit. Studies were made on flower morphology, its duration and fertilization ; they indicated that all peanut flowers are potentially fertile and cannot, therefore, be classed into fertile and infertile types. A description of how the aerial flowers produce subterranean fruits is given.

  20. Distortion of He(2l2l`) Fano lineshapes by strong post-collision interaction in H{sup +}-He collisions

    Energy Technology Data Exchange (ETDEWEB)

    Moretto-Capelle, P.; Benhenni, M.; Bordenave-Montesquieu, D.; Bordenave-Montesquieu, A. [Toulouse-3 Univ., 31 (France)

    1996-05-28

    The three-body post-collisional interaction (PCI) between the scattered proton, recoil target ion and emitted electron has been investigated by electron spectrometry near the 2l2l` helium resonances, in the 20-100 keV energy range (V{sub p} 0.9-2 au). Particular attention has been paid to the PCI deformations of the Fano lineshapes when V-vector``{sub p} {approx_equal} V-vector {sub e}(2l2l`). Their angle and collision velocity dependences have been studied for the first time experimentally. A large variety of lineshapes have been observed, all of them successfully described by a single formula. At the lowest proton velocities the rescattering effect (also called Coulomb two-path scattering) is seen. (Author).